**Anti-Aging E**ff**ects of Calorie Restriction (CR) and CR Mimetics Based on the Senoinflammation Concept**

**Dae Hyun Kim 1, EunJin Bang 1, Hee Jin Jung 1, Sang Gyun Noh 1, Byung Pal Yu 2, Yeon Ja Choi 3,\* and Hae Young Chung 1,\***

Received: 18 December 2019; Accepted: 3 February 2020; Published: 6 February 2020

**Abstract:** Chronic inflammation, a pervasive feature of the aging process, is defined by a continuous, multifarious, low-grade inflammatory response. It is a sustained and systemic phenomenon that aggravates aging and can lead to age-related chronic diseases. In recent years, our understanding of age-related chronic inflammation has advanced through a large number of investigations on aging and calorie restriction (CR). A broader view of age-related inflammation is the concept of senoinflammation, which has an outlook beyond the traditional view, as proposed in our previous work. In this review, we discuss the effects of CR on multiple phases of proinflammatory networks and inflammatory signaling pathways to elucidate the basic mechanism underlying aging. Based on studies on senoinflammation and CR, we recognized that senescence-associated secretory phenotype (SASP), which mainly comprises cytokines and chemokines, was significantly increased during aging, whereas it was suppressed during CR. Further, we recognized that cellular metabolic pathways were also dysregulated in aging; however, CR mimetics reversed these effects. These results further support and enhance our understanding of the novel concept of senoinflammation, which is related to the metabolic changes that occur in the aging process. Furthermore, a thorough elucidation of the effect of CR on senoinflammation will reveal key insights and allow possible interventions in aging mechanisms, thus contributing to the development of new therapies focused on improving health and longevity.

**Keywords:** aging; calorie restriction; senescence-associated secretory phenotype; senoinflammation; mimetics

#### **1. Introduction**

The aging process can be defined as progressive, physiological, functional deterioration throughout the lifetime of an individual by different convoluted interactions among genes and non-genetic environmental factors that eventually result in disruption of homeostasis and increased susceptibility to disease or death. The basic mechanism of the aging process is a sustained, long-term inflammatory state that is further aggravated by elevated oxidative stress due to enhanced reactive oxygen species (ROS), lipid peroxidation, and protein oxidative modifications [1]. To understand the phenomenon of aging and its significance, several concepts and terminologies have been proposed including inflammaging, molecular inflammation, micro-inflammation, pan-inflammation, and gero-inflammation. These

concepts and terminologies are apposite for describing the increased chronic inflammatory events and mediators during aging [2–6].

Generally, cells are continually exposed to and damaged by exogenous and endogenous stress inducers. The cell cycle of damaged cells, which cannot be recovered from cell death, is permanently arrested and the proliferative activity of these cells becomes extinct, which is defined as cellular senescence. This cellular response largely contributes to an organism's aging. Senescent cells have been shown to release multiple inflammatory cytokines and chemokines, which is defined as senescence-associated secretory phenotype (SASP) [7]. An increase in cellular dysregulation due to the release of proinflammatory molecules such as TNF, IL-1β, IL-6, MCP-1, MIP-1α, RANTES, and IL-18 [8,9] induces age-related chronic inflammation, leading to aging and its associated diseases.

In order to understand age-related chronic inflammatory progress from a multilayered point of view, we previously proposed a novel concept of senoinflammation, which includes an expanded systemic view of chronic inflammation during the aging process.

CR is a well-known gold standard for many aging intervention strategies. A number of age-related biological changes and pathologic abnormalities can be delayed or suppressed by CR regardless of gender and species (mammalian or non-mammalian) [10]. CR has been shown to suppress oxidative damage-induced alterations and age-related diseases and to extend lifespan [11]. In this review, we focus on the diverse protective effects of CR against aging from a senoinflammatory perspective. In addition, the beneficial effects of CR mimetics and other types of dietary restrictions on anti-aging are covered.

#### **2. Age-related Inflammation and Senoinflammation**

Senescent cells produce proinflammatory senescence-associated (SA) secretome, which is referred to as the SASP. Macrophages are recruited in the secretome by chemotactic factors to clear senescent cells [12]. However, senescent macrophages with M2 polarized phenotype secrete proinflammatory cytokines and exhibit impaired phagocytosis and chemotaxis, and a downregulated rate of cellular proliferation [13–15]. It has been proposed that deficiency in the ability of aged macrophages to clear senescent cells leads to increased inflammatory response and results in chronic inflammation as SASP plays a role in the initiation of tissue inflammation [16]. Based on previous observations and evidence of the aging process at molecular and cellular levels, we coined the term "senescent inflammation (senoinflammation)" with a new framework (Figure 1) in our recent review to provide an expanded, broader view of age-related chronic inflammation and metabolic dysfunction [17].

Aging in hepatocytes is associated with various markers of cellular senescence, such as increased expression of heterochromatin protein 1β, and increased activity of senescence-associated-β-galactosidase, p21 and p16 [18]. p53 expression is an important marker of cellular senescence and DNA damage in the normal liver [19], and its regulation depends on the nutrient-sensing pathways of non-alcoholic fatty liver disease (NAFLD) [20]. Senescent hepatocytes exhibit increased lipid droplet accumulation and ROS production [21].

In understanding age-related inflammation at the molecular level, an abundance of data in our and other previous work strongly suggested that NF-κB is a key player involved in the initiation and exacerbation of tissue inflammation in the aging process and cancer [22–24]. Chronic transactivation of NF-κB has been observed in multiple tissues in various experimental models of aging and human fibroblasts and human CD4+ T cells obtained from aged individuals [25,26]. NF-κB induces proinflammatory mediators, chemokines, and adhesion molecules [27] and interacts with other transcriptional factors that are involved in the initiation and deterioration of chronic inflammatory response including signal transducers, the activator of transcription 3 (STAT3) and p53 [22]. The transcriptional activity of NF-κB occurs concurrently with crosstalk among upstream signaling components such as glycogen synthase kinase 3 (GSK3)-β, mitogen-activated protein kinase (MAPK), mammalian target of rapamycin (mTOR), and protein kinase B (PKB) [23,28].

**Figure 1.** Possible mechanism of senoinflammation in aging. During aging, the continuous age-related inflammatory responses that cause metabolic dysregulation to form a vicious cycle. Age-related inflammation and metabolic dysregulation result in the induction and activation of many pro-inflammatory genes, metabolic and signaling pathways, and SASP. This vicious cycle of age-related chronic inflammation and metabolic dysregulation underlies the senoinflammation phenomenon, which occurs because of the interaction between senescent cells, immune cells, adipocytes, hepatocytes, and myocytes. SASP, senescence associated secretory phenotype; CR, calorie restriction.

The upregulation of systemic inflammation is associated with aging and age-related chronic diseases [29,30]. As mentioned, age-related systemic inflammation and senoinflammation are functionally distinct from acute inflammatory responses due to sustained high levels of pro-inflammatory mediators. In fact, epidemiological and experimental results suggest that persistent low-grade, chronic inflammation exists in aged animals [31,32]. A recent longitudinal, semi-supercentenarian study in Japan has demonstrated that inflammation, and not telomere length, strongly predicts successful aging at extremely old age [33]. This study concluded that chronic and systemic inflammation has a significant effect on mortality and had a correlation with the decline in cognitive function in the centenarians, thus showing that chronic inflammation is a critical risk factor in the aging process [33]. An increase in systemic inflammation is related to many aging phenotypes. For example, abruptly increased inflammation is generally associated with tissue dysfunction, metabolic syndrome, immune dysfunction, and neuronal complications [34].

CR animals live fairly longer with the right amount of nutrients, and most of the typical age-related chronic diseases are prevented or delayed in them. For example, the incidence of cancer, the main cause of death in rodents, is significantly reduced in CR animals. Similarly, reduced incidence or slower disease progression has been reported for cardiomyopathy, diabetes, chronic lung diseases, autoimmune diseases, and neurodegenerative diseases [35,36]. Preclinical and preliminary clinical studies have shown that CR or fasting can effectively prevent the development of malignant tumors through a variety of cellular responses and can improve the efficacy of therapeutics [37]. CR reverses most symptoms of immunosenescence, including decreased naïve T cell and increased memory T cell population [38], reduced T cell proliferative response to mitogens or antigens, reduced IL-2 production

and NK activity [38–42], age-related increase in serum levels of TNFα and IL-6 [43], and autoimmune diseases [44,45]. More recently, CR was shown to delay immunosenescence in animals; however, this effect needs to be confirmed in humans.

Therefore, the concept of senoinflammation shows the orchestral performance of activated pro-inflammatory cytokines and transcription factors at a molecular level, immune cell senescence and SASP at a cellular level, and systemic inflammation and metabolic disorders at a systemic level during the aging process.

#### **3. Calorie Restriction**

In an initial study on CR by McCay et al. [46], the growth retardation hypothesis was investigated in a rat model by reducing food intake or CR, which slowed down the growth rate and prolonged lifespan. Various additional studies on CR have been conducted in diverse species ranging from yeast, fish, drosophila, hamsters, dogs, and non-human primates to humans [47]. Experts in the field of aging have accepted CR as an anti-aging experimental concept, which serves as an established aging intervention. As CR is a non-genetic, nutritional means to delay the aging process, it was used to identify underlying signaling mechanisms of aging, resulting in its considerable importance. Understanding elemental mechanisms underlying the effect of CR is critical as they may aid in identifying novel therapeutic molecular targets for age-associated inflammatory pathological conditions.

Previous studies conducted at the molecular level significantly support the hypothesis that CR is capable of reducing age-associated oxidative stress and suppressing systemic, chronic inflammation [48]. CR and its anti-aging effects are majorly considered due to its significant regulatory role in oxidative stress and capability to sustain appropriate cellular redox conditions [1]. CR also has beneficial effects in the inhibition of protein synthesis and the oxidization of proteins in the liver and skeletal muscle. Furthermore, it enhances immune functions and inhibits inflammatory responses during the aging process [49]. CR exerts preventive or delaying effects on age-associated diseases, such as chronic nephropathies, cardiomyopathies, diabetes, autoimmune conditions and respiratory diseases, as well as aging [48,50]. Implementation of CR in mice suppressed the degree of neurological degeneration and β-amyloid deposition in the brain tissue and subsequently promoted the generation of neurons in in vivo animal models of Alzheimer, Parkinson, and Huntington diseases [51,52]. The results of the first randomized clinical human trial on CR highlighted a reduced probability of developing age-related diseases and improved number of biomarkers showing health longevity.

#### **4. Anti-senoinflammatory E**ff**ect of CR**

Many interventions and strategies for modulating chronic inflammation and anti-aging have been scientifically demonstrated. Among many well-described anti-aging strategies, CR has been identified as one of the most powerful interventions to fight the aging process and age-related pathological conditions such as diabetes, obesity, cardiovascular diseases, rheumatoid arthritis, Alzheimer's disease and more [53]. Although the detailed molecular mechanisms and signaling pathways underlying CR still require further investigation, previous evidence for modulatory action of CR in senoinflammation suggest potential therapeutic effects of CR on aging (Table 1). For example, at a molecular level, CR exhibits powerful anti-inflammatory effects by suppressing key pro-inflammatory mediators such as NF-κB, IL-1β, IL-6, TNF, cyclooxygenase 2 (COX-2), and inducible nitric oxide synthase (iNOS) [54–56]. In addition, CR was shown to regulate the activity of pro-inflammatory upstream signaling pathway molecules such as MAPKs (ERK, JNK, p38), and NIK/IKKs. CR was also shown to regulate the DNA binding activity of NF-κB and AP-1 transcription factors and expression of their corresponding genes, *COX-1* and *iNOS* [55,57]. CR was also shown to reduce the plasma concentration of cytokines, TNF, ICAM-1 and to induce cortisol release, which suppresses the systemic inflammatory response [58,59]. In obese mice models, implementation of 30% CR for 2 months notably decreased the levels of adipose tissue cytokines and chemokines, including IL-6, IL-2, IL-1Rα, MCP-1, and CXCL16, which are considered as major components of SASP [60]. In hepatic tissue, even mild CR notably suppressed

proinflammatory and lipogenic gene expression of molecules such as MCP-1, SREBPs, and peroxisome proliferator-activated receptor (PPAR)-γ [61]. These evidences suggest that CR successfully regulates the symptomatic prevalence of senoinflammation that expands to pathological conditions such as chronic inflammation, insulin resistance, and low energy metabolism [17,58,62,63].

Regarding anti-aging effects, CR is known to play an important role in suppressing oxidative stress and damage [64,65]. Cellular oxidative stress leads to formation of ROS, hydrogen peroxide, reactive nitrogen species, peroxynitrites, which then induce cellular inflammation, damage, and senescence. CR exerts its beneficial, maximal life-spanning effects by partially attenuating oxidative stress. For example, age-dependent functional decline of mitochondria in cardiac tissue, a major organelle of ROS production, has been well documented. Additionally, it was demonstrated that CR attenuates oxidative damage in an aged heart by lowering the levels of 8-oxodG, an oxidative damage DNA biomarker [66].

In addition to the anti-inflammatory effects described above, CR is also well known for regulating the expression of various genes involved in regulating energy metabolism. In regulating lipid metabolism, the PPARs could sense fatty acid molecules released from dietary lipids and their metabolites. PPARs are specialized receptors that recognize and bind lipid metabolites to transmit signals and can regulate lipid and carbohydrate metabolisms and inflammation. Among three subtypes of PPARs, PPARα and PPARγ have been well investigated and both have been suggested as regulators of inflammatory responses. In an aged rat model, the expression of *PPAR*α and *PPAR*γ genes was decreased and age-associated alterations were reversed by CR [63,67]. In a previous review, it has been noted that suppression of PPAR activity leads to upregulation of cytosolic IκB and NF-κB inhibitor, and suppression of NF-κB activation [68]. Such experimental evidence further strengthens the fact that PPARα agonists could alleviate age-related inflammation by suppressing NF-κB-mediated proinflammatory cytokine production [67,69].

CR modulates nutrient-signaling pathway molecules such as sirtuin proteins. One major molecule known to exert its effects in delaying aging and increasing longevity during CR is SIRT1 [70]. Sirtuins regulate protein expression in diverse cellular processes such as DNA repair, epigenetic modification of chromatin, ROS production, and metabolism. CR is well known to promote SIRT expression and activation in the liver, adipose tissue, brain and kidney by interacting with FOXOs, PGC1α, p53 and NF-κB to mediate anti-aging effects [71]. CR-mediated SIRT1 activity regulates pro-inflammatory NF-κB activation. For example, SIRT1 induces deacetylation and suppresses NF-κB activation [72,73].

Diverse research has provided an understanding of the association between aging and CR and the effects of CR on senoinflammatory and metabolic signaling pathways. The experimental evidence suggests that CR exerts beneficial effects on senoinflammation during aging by altering molecular pathways through regulation of expression and activities of core molecules such as NF-κB, PPARs, SIRT1, and others. Collective evidence on CR further supports the concept of senoinflammation during the aging process and confirms the positive role of CR against aging. In addition, the evidence strongly supports the notion that the anti-aging effects of CR are due to the alleviation of systematic physiological senoinflammatory response. However, further research is needed to clearly define the signaling mechanisms in detail.

#### **5. Omics Big Data on Aging and CR**

The immense amount of collected data in the field of biology and biomedicine research necessitates integrative data analysis to understand a complicated physiological system as a whole. Integrative dataset analysis has also provided an understanding of the underlying mechanism of aging and age-dependent changes at molecular, cellular, and physiological levels. An immense amount of data on age-related diseases enables the building of interactive networks and alterations in these networks may aid in developing aging intervention methods. Transcriptomics is the study of complete sets of RNA transcripts of a whole genome under certain conditions, which includes analysis of comparative differential gene expression in response to different conditions. As the biological aging process is complex and heterogeneous, defining specific mechanism of aging and a potential intervention method such as CR requires data integrative analysis based on age-dependent changes at the molecular level.

Among Omics Big Data analysis, gene set enrichment analysis (GSEA) allows the identification of gene types that are significantly associated with the disease. In order to analyze young and aged groups, RNA-sequencing data were collected and analyzed by the GSEA method to detect the set of differentially expressed genes or DEGs. Based on the results, it was demonstrated that proinflammatory functional genes, including cytokines, chemokines, TNF and toll-like receptors (TLRs), were notably over-represented in the aged group, whereas genes associated with metabolism, such as fatty acid metabolism and PPAR pathways, were significantly suppressed. This suggests that aging is highly associated with gene expression alterations including increased expression of inflammatory genes and decreased expression of metabolic genes. In addition, it was found that these changes were reversed by CR, a well-known aging intervention method [74].

By detecting DEGs, the Omics Big Data analysis method can identify informative epigenetic modifications along with the changes in gene expression and potential biomarkers of aging and age-related pathologic conditions. The results of a previous epigenetic study, performed using collective genomic data program called The Cancer Genome Atlas (TCGA) Program, indicated various age-related changes in the pattern of DNA hypomethylation in young and old subjects. In particular, the genes that were upregulated and hypomethylated were *AZU1*, *ELF3*, *NOX1*, *IL1B,* and *S100A12*; these genes are known to function in inflammatory responses, indicating that inflammatory genes are involved in age-related cancer onset and progression [75]. A previous briefing paper discussed the idea of big data in the field of medicine and suggested that a big network constructed by multi-omics data such as epigenomics, transcriptomics, and metabolomics can detect a significant association existing between aging and inflammation, indicating the use of a systems biology tool to identify new genes involved in inflammaging [76].

Omics Big Data is a useful tool to investigate the beneficial effects of CR. The transcriptome profile of mice liver tissue obtained after implementation of CR showed that CR improved the expression of genes associated with health, which were previously modulated by obesity. These data and other research studies collectively indicate that CR promotes beneficial outcomes leading to the expansion of life span [77]. In another study, transcriptomic data of adipose tissue indicated that CR suppresses transcription and activity of genes involved in inflammatory response, for example, the NF-κB signaling molecule gene. Additionally, in that study, diverse evidence indicated that CR has protective effects in physiological systems [78]. Furthermore, based on a global mass spectrometry-based metabolomics study, graded CR (10, 20, 30, 40% CR) modulated metabolic signaling pathways, including the carnitine synthesis and shuttle pathway and sphingosine-1-phosphate and methionine metabolism, in a graded manner. The expression of various metabolites was modulated by CR, indicating that CR could ameliorate the energy release process of hepatic fatty acids [79]. In addition, augmented gene–gene network connectivity analysis has shown that CR changed the network arrangement and biological gene centrality in a CR level-dependent manner. Therefore, the results suggested that CR-induced genes play a critical role in countering the age-associated loss of gene–gene network connectivity [80]. In order to better understand the mechanism of CR in age-associated pathological symptoms, its relation to insulin sensitivity has also been investigated. Multi-omics approaches that integrate transcriptomics, metabolomics, and microbiomics data were used to further enhance our previous knowledge that CR induced amelioration of insulin sensitivity and lifestyle, gut microbiome, and extrinsic environmental factors. Furthermore, it identified potential biomarkers that could be used for personalized weight-loss interventions [81].

Analysis of transcriptomic data from different tissues shows that aging induces the upregulation of inflammatory pathways and downregulation of metabolic pathways. In contrast, CR intervention reverses such effects, in which it downregulates the immune response and upregulates the metabolic pathways. In particular, LCK, a key signaling molecule in the development of T cells, was significantly upregulated in aged tissues and later downregulated as a consequence of CR. This identification of

*LCK* gene was based on integrative analysis of cDNA microarray and interactome, which showed a high degree of centrality and between centrality analyses. These results suggest that immune and inflammatory responses are increased during aging and can be modulated by CR [82]. In support of such results, Hong et al. reported that CR successfully suppressed immune response and increased lipid metabolism, thereby delaying aging and preventing age-associated diseases [83]. Kim et al. also reported that CR implementation delayed age-associated alterations of DNA methylation, which could prevent the progression of age-related diseases [84].

Other omics studies provided evidence that CR definitively modulates aging processes and prevents or delays age-associated disease progression. Analysis of hepatic transcriptome showed that CR stimulated pathways involving IGF-1, NF-κB, mTOR, and SIRTs, which collectively contribute to reduced oxidative stress and improved metabolism, further supporting that CR promotes health and could extend lifespan by interfering with age-associated signaling pathways [85]. In addition, CR suppresses adiposity and insulin resistance, consequentially suppressing a proinflammatory status. By implementing CR, DEG analysis could help identify biomarkers that are closely related to age-associated diseases, including metabolic disease [86]. In support of the beneficial effects of CR in aging, one of the proteomics analyses demonstrated that CR improved glucose and lipid energy metabolism and suppressed oxidative stress [87]. As lipid composition was one of the critical determinants of aging, using CR as an intervention method, a research group conducted LC–MS and demonstrated that CR reprogrammed the lipidome and metabolome, which lowered the protein oxidative damage, sequentially increasing lifespan and healthspan [88].

#### **6. Preventive E**ff**ects of Other Types of Dietary Restriction in Aging**

CR is usually considered for reducing overall calorie intake or food intake without malnutrition. In animal models, under CR, food intake is reduced by around 10–50% compared with ad libitum-fed controls [89]. Although CR exhibits preventive effects on age-related phenotypes, to practice and sustain CR in human life is quite challenging. In efforts to improve human health during aging, there are other types of dietary restriction and pharmacological interventions available that mimic CR. Here, we introduce other types of dietary restriction and CR mimetics, recapturing the beneficial effects of CR in the present and next sections.

Reduced intake of specific nutrients, rather than reduced intake of total calories, was considered important for health benefits of a restricted diet. The reduction of either dietary protein or sugar can reduce mortality and extend life span in Drosophila, independent of the calorie intake [90]. A study by Solon-Biet et al. in mice showed a clear correlation between the ratio of protein to carbohydrate and lifespan. Mice were fed 25 diets differing systematically in protein, carbohydrate, and fat content. The energy density and median lifespan of the mice increased by up to 30% as the protein to carbohydrate ratio decreased [91]. In addition, it is suggested that reduced intake of specific essential amino acids such as methionine, tryptophan, or branched chain amino acids can delay aging or improve health [92,93].

Intermittent (ex. alternate day fasting) and periodic (fasting that lasts three days or longer, every two or more weeks) fasting have been studied as alternative dietary interventions for long-term CR [94]. The effects of fasting on lifespan extension have been reported in various species including bacteria [95], yeast [96], worm [97], and mice [98]. Intermittent fasting has a protective effect on age-dependent diseases including diabetes, cancer, heart disease, and neurodegenerative disorders in rodents [94]. There are various regimens of fasting. Recently, the fasting mimicking diet (FMD) was developed and has shown several beneficial effects in mice including extended longevity, lowered visceral fat, reduced cancer incidence and skin lesions, rejuvenated immune system, and retarded bone mineral and hippocampal neurogenesis [99].

#### **7. CR Mimetics in Aging**

CR mimetics are compounds that mimic the benefits of CR at the molecular, cellular, and physiological levels, leading to health-promoting effects [100]. Recently, there has been an increased interest in CR mimetics due to the benefits of using these anti-aging interventions in terms of extended health and lifespan [101–103]. Although the valuable effects of CR mimetics on lifespan and health have been extensively highlighted, limitations persist because it is difficult to implement such diet regimens in humans. In this section, we summarize the current knowledge of CR mimetic compounds and highlight their typical effects.

#### *7.1. Resveratrol*

Resveratrol (3,5,4- -Trihydroxystilbene), a natural polyphenolic, phytoalexin compound found in grapes, cranberries, and peanuts, is currently the most thoroughly studied CR mimetic. Resveratrol promotes lifespan extension across a range of evolutionarily distinct sets of species, including *Saccharomyces cerevisiae, Caenorhabditis elegans,* and *Drosophila melanogaster*, all the way to mammals such as mice [104]. Previous studies have indicated the beneficial effects of sirtuins as the best small molecule that activate sirtuins, which extended lifespan in a yeast model [104–109]. Although only the longevity extension effect of resveratrol has been reported in *C. elegans* and *D. melanogaster*, many subsequent studies reported that resveratrol intake promotes health and plays a preventive role in age-related diseases, such as cancer [110–113], atherosclerosis [114,115], arthritis [116,117], cataract [118–120], cardiovascular disease [121], hypertension [122,123], type 2 diabetes [124–127], osteoporosis [128–130], and Alzheimer disease [131–133]. In clinical studies, resveratrol intake improved the memory capacity of elderly individuals and reduced blood lipid levels in obese and type 2 diabetic patients [134,135]. However, additional studies are required to investigate intake duration and dose-dependent metabolic effects of resveratrol supplements required to overcome metabolic irregularity in human subjects. Resveratrol suppresses SASP through SIRT1/NF-κB signaling and delays aging [136], represses cellular senescence, and improves insulin resistance in muscle [137].

#### *7.2. Metformin*

Metformin, a biguanide used as a first-line drug for treating type 2 diabetes [138], was shown to extend the lifespan of *C. elegans* [139–141], *D. melanogaster* [142], and mice [143,144]. Moreover, it was shown to delay the onset of age-related diseases, such as cancer, metabolic syndrome [145], and cognitive disorders [146]. Its mechanism of action is associated with the activation of 5- AMP-activated protein kinase (AMPK) [147,148], inhibition of the mammalian target of rapamycin (mTOR) [149], reduction of DNA damage [150,151], and decreased insulin levels and IGF-1 signaling [152–154]. The longevity effect of metformin has not yet been identified in humans, and therefore, its mechanism of action requires further investigation. Metformin regulates mitochondrial biogenesis and cellular senescence through SIRT3 [155], and decreases oxidative stress-induced senescence by activating autophagy [156].

#### *7.3. Rapamycin*

Rapamycin, (International Nonproprietary Name: sirolimus), is an inhibitor of mTOR, which results in an extended life span and prevents age-related diseases [157–160] by mediating SIRT1 expression [161,162]. mTOR is a serine-threonine kinase that plays a role in modulating cell survival, growth, proliferation, motility, protein synthesis and transcription [163] and inducing autophagy [164–166]. In addition, mTOR promotes growth and aging in *C. elegans* [167], *D. melanogaster* [168], *S. cerevisiae* [169], as well as in mice [170,171] and rat [172,173] models. Further, it modulates glucose and lipid metabolism [174,175]. Rapamycin prevents insulin resistance in humans [176], reduces insulin resistance in hyperinsulinemia rats [177,178], and normalizes glucose metabolism in diabetic mice [179,180]. Recently, Garcia et al. [181] reported that rapamycin treatment

has a mechanism similar to CR in ovarian mice, which increases *FOXO3* gene expression. Thus, the use of rapamycin as a CR mimetic needs to be investigated further for understanding significant signaling pathways that can be targeted for enhancing its therapeutic potential. Rapamycin ameliorates age-related late-life cancer by inhibiting senescence-associated inflammation [182]. It is also an effective inhibitor of cellular senescence [183].

#### *7.4. PPAR Agonists*

In addition to the anti-inflammatory effect, PPARs have diverse biological effects including the promotion of cellular proliferation, glucose and lipid metabolism, insulin sensitivity, and tissue remodeling processes [67,184]. Because of their association with multiple metabolic processes, PPARs have been suggested to play roles in pathogenic conditions such as obesity, metabolic syndrome, diabetes, NAFLD, and atherosclerosis. Therefore, PPARs have been considered as important molecular targets for the discovery and development of new drugs to treat these age-related diseases [185–188].

Fenofibrate is a PPARα agonist used for the treatment of hyperlipidemia, hyperglycemia, and hypertriglyceridemia [189,190]. PPARα activation by fenofibrate also reduces renal oxidative stress and cellular apoptosis in aging-related renal injury through AMPK-SIRT1 and AMPK-PGC1α signaling pathways [191]. The activation of PPARα, AMPK, and SIRT1 has been shown to protect aging-related renal injury. PPARβ/δ is involved in the regulation of insulin sensitivity, adipogenesis, lipid and energy metabolism, inflammation, and atherosclerosis [192–194]. A specific PPARβ/δ agonist, GW501516, attenuates inflammation, insulin resistance, and dyslipidemia, and modulates angiogenesis [192,193]. Two thiazolidinediones (TZD), rosiglitazone and pioglitazone, which are also PPARγ agonists, have been shown to be effective in the treatment of type 2 diabetes [195,196]. Further, they are also associated with human life longevity and cell senescence [197]; this has also been observed in aged rats [198]. Recently, Patel et al. [199–201] reported that a novel dual PPARα/γ agonist, saroglitazar magnesium, was used in the treatment of dyslipidemia and metabolic disorders in in vivo and healthy Indian adult subjects. These results are further supported by the results of a preclinical study conducted by Kaul et al. [201]. Notably, Xu et al. [202] reported that chiglitazar acts as a PPAR-α/β/γ pan agonist and evaluated its use in diabetic therapeutics in healthy Chinese volunteers.

Recent data support PPAR agonists as potential candidates for anti-senoinflammation therapy. Our group synthesized MHY908, new a PPARα/γ dual agonist, and showed that it has a significant inhibitory effect on age-related inflammation and insulin resistance [203]. It is reported that PPAR activation might have an effect on the prevention of cell senescence and that PPARα silencing induces cancer cell senescence. Rosiglitazone significantly suppressed olaparib (a PARP inhibitor)-induced cellular senescence and SASP in ovarian cancer [204].

Collectively, identifying the role of PPAR agonists in various metabolic or non-metabolic organs and pathological conditions will contribute to the development of new therapeutic options and promising anti-senoinflammatory chemicals for the treatment of many age-related metabolic disorders.

#### *7.5. Ketone Bodies*

Ketone bodies such as β-hydroxybutyrate (HB), acetoacetate, and acetone are water-soluble molecules that are generated from fatty acids in the mitochondrial matrix of the liver. They serve as moving energy sources for physiological systems during periods of fasting [205]. The process of ketogenesis starts within 24 h of fasting through gluconeogenesis [206]. In humans, physiological serum levels of HB are normally maintained at a low micromolar concentration, which increases to a few hundred micromoles after 12 to 16 h of the fasting period and eventually reaches 1 to 2 mM after 2 days of fasting [207]. Insulin inhibits lipolysis of adipose tissue and restricts ketogenesis, while glucagon promotes ketogenic flow by exerting its direct effect on the hepatic tissue [208]. In a study, CR or fasting interventions elevated the circulating concentration of ketone bodies, HB, compared to that in a normal feeding group [209,210]. Furthermore, it has also been reported that the implementation of a ketogenic diet exerts therapeutic effects on various age-related diseases related to insulin resistance, as well as diseases resulting from free radical damage and hypoxia [211].

HB also acts as a signaling molecule and activates cellular signaling pathways. For example, HB plays a role in endogenously inhibiting histone deacetylases (HDACs) [209]. Suppression of HDAC activity exerts beneficial metabolic and cytoprotective effects similar to those seen in HB investigations [212]. However, SIRT3 regulates diverse pathways involved in fasting metabolism, and mice without *SIRT3* genes have decreased HB concentration during fasting [188]. Ketogenic diets are also related to low levels of insulin [213,214], suppressed IGF signaling [215], induction of FOXO3 [209], and activation of AMPK [215,216] and antioxidant genes [209]. Ketone bodies exert neuroprotective and lifespan extension effects similar to CR in *C. elegans* [217]. HB upregulates transcription of antioxidant genes, including manganese superoxide dismutase (*MnSOD*) and *FOXO3*, both of which exert antioxidant effects [209]. It is thought that HB exerts its effect through signaling mechanisms comparable to that of CR by inducing co-activation of FOXO1/PGC-1α through deactivation of the PI3K/Akt pathway [218].

HB is an effector that transduces signals via G-protein coupled receptors. It represses the actions of the sympathetic nervous system and decreases energy expenditure and heart rate by blocking fatty acid signaling pathways through the G protein-coupled receptor 41 [219]. One of the most well-studied signaling effects of HB signals is via GPR109A, a member of the hydrocarboxylic acid GPCR subfamily that is expressed in adipose tissues (white and brown) [220] and immune cells [221]. Although the GPR109A receptor has protective effects, associations have been found between ketogenic dietary intervention use in stroke patients and neurodegenerative diseases [222,223]. In a TNFα or LPS-induced inflammatory setting, HB exerts anti-inflammatory effects by suppressing the release of pro-inflammatory proteins (iNOS and COX-2) and cytokines (TNF, IL-1β, IL-6 and CCL2/MCP-1), which seems to occur partially via inhibition of NF-κB translocation to the nucleus for pro-inflammatory gene activation [224,225]. However, in neurodegenerative inflammatory conditions, the effects of GPR109A-mediated HB do not appear to involve inflammatory mediator signaling via the MAPK pathway [224]. In addition to their role in providing energy fuels for various key organs and tissues, including the brain, heart or skeletal muscle, ketone bodies play critical roles as signaling mediators and modulators of inflammation and oxidation [226].

#### **8. Conclusions**

Based on the available molecular and biochemical evidence, we proposed the concept of senoinflammation in our previous review [17,227]. The concept proposes a broader perspective on age-related inflammatory response and creates a complex network among many inflammatory mediators that can lead to systemic chronic inflammation. Oxidative stress leads to improper gene regulation and genomic DNA damage during aging. Such improper gene regulation in aged senescent cells allows them to fall into a proinflammatory state, consequently changing systemic chemokine or cytokine activities. The proinflammatory SASP environment further exerts stress on the intracellular organelles, tissues, and systems, which affects the development and occurrence of metabolic disorders. It appears that a repetitive vicious cycle occurs between SASP and metabolic dysregulation as proposed in the concept of senoinflammation, and this interactive network forms the basis of the aging process and age-related diseases. However, the secretion of proinflammatory mediators, collectively termed as SASP, in response to internal and external stress leads to the chronic inflammatory condition termed as senoinflammation. Based on CR experiments and observations, cytokine, chemokine, and metabolic pathways are significantly regulated by CR and CR mimetics in the aging process. It is expected that a better understanding of senoinflammation modulatory mechanisms will provide a basis for the discovery of molecular targets that can therapeutically modulate age-related chronic inflammatory conditions and enable the development of potentially effective interventions to delay aging and prevent the occurrence of aging-associated diseases.

**Table 1.** Changes in parameters in senoinflammation.

\* A calorie restriction (CR) diet supplemented with fish oil. SASP, senescence-associated secretory phenotype; IL-1β, Interleukin 1 beta; IL-6R, Interleukin 6 receptor; TNF-α, Tumor necrosis factor-alpha; MCP-1, Monocyte chemoattractant protein-1; MIP-1α, Macrophage inflammatory protein-1alpha; MMP, Matrix metallopeptidases; GF, Growth factor; HGF, Hepatocyte Growth Factor; EGFR, Epidermal growth factor receptor; FAS, Apoptosis Antigen 1; IGFBP2, Insulin Like Growth Factor Binding Protein 2; TCGA, The Cancer Genome Atlas.

**Author Contributions:** Conceptualization, design and writing of the work: D.H.K., E.B., H.J.J., S.G.N., B.P.Y., Y.J.C. and H.Y.C. All authors have read and agreed to the published version of the manuscript.

**Funding:** This study was supported by the Korean National Research Foundation (NRF) funded by the Korean government (NRF-2018R1A2A3075425 and NRF-2015M3A9B8029074).

**Acknowledgments:** We thank Aging Tissue Bank (Busan, Korea) for providing research information.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

*Review*


**3. Research framework, the purpose of the case study**

The amount of innovation, originality, and ISO certifications in the form granted for each nation for which data could be gathered served as the framework for the study of the global entrepreneurship ecosystem [68].

*A Worldwide Regression Analysis of Relations between Creativity, Innovation, and Quality… DOI: http://dx.doi.org/10.5772/intechopen.111744*

The purpose of this research is to fill this gap in the literature regarding the relationships between creativity and innovation, creativity and quality management, and quality management and innovation. Additionally, this research has adopted a theory-building approach with the following objectives [68]:

1.RQ1: Is there any relationship between innovation and creativity?

2.RQ2: Is there any relationship between quality management and innovation?

3.RQ3: Is there any relationship between quality management and creativity.


**4. Conclusion**

As a result of this review compilation, it was concluded that the two main general factors that determine thermal resistance of PUs are its structure from one side and the presence of additives on the other side. The structural factors that influence thermal stability of PUs are the chemical nature and composition of hard (isocyanate plus chain extender) and soft (macrodiol) segments, its segregation, and PU thermoplasticity (derived from characteristic of TPU's stable linear structure). The additives that have a marked effect on augmenting thermal stability of PUs are mineral fillers (e.g., nano-oxides, nanoclays, talcs) and specific modifiers like POSS, flame retardants (both as additive and as polyol modifier), and fibers (natural or synthetic). Also, blending and grafting with other polymers are strategies that are utilized for increasing thermal resistance of PU, both for improving processing in manufacture and for high demanding applications. However, it is necessary to state that this review did not attempt to cover all particular factors that need to be taken into account when studying thermal stability of PU. Complex PU structures will

## *Thermosoftening Plastics*

potentially have several weak chemical links, variable intermolecular forces, different relevant properties such as thermal conductivities, and even environmental factors that may cause decomposition (i.e., hydrolysis by moisture, acidity, oxidative or non-oxidative atmosphere) will contribute to only predict thermal stability in more or less broad temperature ranges.


Preface

Helminthiases, caused by the larval or adult stage of various genera of worms, are a serious health and veterinary problem in many developing countries and are considered the most important neglected tropical diseases (NTDs) in developed countries. A great deal of scientific advances have occurred in this field, including in vaccination, epidemiology, drug design, management and diagnostics, and host–parasite interaction at all levels. Recently, the One Health approach has been proposed as a global way to treat and control helminthiasis. This book provides a comprehensive overview of the current state of the art in helminthiases. It highlights the most recent advances in the study of helminth infections, addressing topics such as clinical disease, vaccines, immune response, new possible drug targets, and basic molecular research.

The book is divided into five sections:

Section 1 includes five chapters. Chapter 1, "Therapeutic Properties of *Trichinella spiralis* (Nematoda) in Chronic Degenerative Diseases" by Nevárez-Lechuga et al., discusses diseases produced by helminth parasites. These diseases occur frequently in underdeveloped countries where they present a serious public health problem. However, these regions exhibit a low rate of autoimmune and allergic diseases. As such, some researchers have proposed that some helminths, such as *Trichinella spiralis* or its proteins, have strong anti-inflammatory potential, or have assessed them as modulating agents of the immune response. *T. spiralis* shifts the host immune response from a Th1 profile, characterized by pro-inflammatory cytokines, to a Th2 profile, characterized by the release of different cytokines with anti-inflammatory properties. Thus, the chapter authors point out that this parasite has shown high therapeutic potential in a wide variety of disease models. In one of the most promising, the experimental lupus model in mice, the release of anti-inflammatory cytokines IL-4 and IL-10 and delayed onset of the key clinical features of the experimental lupus model for at least 5 months were observed, when previously parasitized. This is the first study to date that focuses on the use of *T. spiralis* as an

immunomodulator in lupus disease. The authors conclude that further study of the immune response generated by the parasite is necessary to advance the development of new therapies for inflammatory diseases.

Chapter 2, "Anthelmintic Drug Resistance in Livestock: Current Understanding and Future Trends" by Muhammad Abdullah Malik et al., discusses how anthelmintic, ectoparasiticides (insecticides, acaricides) and antiprotozoal chemotherapeutic drugs target parasites. *Chenopodium* oil-like alkaloids, arsenic compounds, cupric sulfate, nicotine, and cupric silicate have been used to destroy nematodes. Unfortunately, these chemicals are less effective and less safe for livestock. The four major groups of broad-spectrum antinematodal compounds are macrocyclic lactones such as milbemycins/ivermectin, benzimidazole/pro-benzimidazole, tetrahydro pyrimidines such as morantel, pyrantel tartrate, and imidazothiazoles such as tetramisole and levamisole. The various factors responsible for gastrointestinal parasitism make it difficult to develop effective control measures. Hence, an effective strategy for the control of parasitic diseases that does not solely rely on anthelmintic therapies needs to be developed at the regional level, based on the epidemiology of the disease.

Chapter 3, "Recent Advances in Anti-Schistosomiasis Drug Discovery" by Ezra J. Marker and Stefan L. Debbert, discusses schistosomiasis, a parasitic disease caused by infection by helminths of the *Schistosoma* genus that affects more than 200 million people, primarily in the developing world. Treatment of this disease largely relies on one drug, praziquantel. Although this drug is cheap, safe, and effective, the looming prospect of drug resistance makes the development of a pipeline of antischistosomiasis drugs a priority. Many new drug leads have arisen from screening existing sets of compounds such as the Open Access Boxes developed by the Medicines for Malaria Venture (MMV) in collaboration with the Drugs for Neglected Diseases Initiative (DNDI). Other leads have been found through work focused on druggable targets such as kinases, histone deacetylases, proteases, and others. Thus, the chapter discusses recent work concerning the discovery and development of novel anti-schistosomiasis drug leads from many sources.

Chapter 4, "Perspective Chapter: Application of Probiotics to Inactivate Helminth Parasitic Zoonosis" by Osama M. Darwesh and Hoda Samir El-Sayed, discusses zoonotic infections, which are animal infections that might be transmissible to people. The infection may be transmitted through ingestion of contaminated food, infected soil, skin penetration, or direct animal contact. Parasitic helminths are a group of parasites that remain poorly studied in comparison to viruses and bacteria but may pose considerable future risk to humans. Zoonotic parasites may be separated into four classes: direct-zoonotic, meta-zoonotic, cyclo-zoonotic, and saprozoonotic. It is possible to prevent helminth parasitic zoonosis via proper hygiene and sanitation or regular deworming with anthelmintic pills. However, because of the lack of effective vaccines and anthelmintic resistance to medication, suppression of parasitic infestation requires new techniques. One potential treatment involves probiotics, which are exogenous residing microorganisms that are beneficial to the host's fitness when administered inside the digestive tract. The most extensively used microorganisms for this purpose are of the genus *Lactobacillus* and *Enterococcus*, along with a few fungi and yeasts.

Chapter 5, "New Uses for Old Drugs and their Application in Helminthology" by Del Río-Araiza et al., examines parasitic infection research performed on both humans and domestic animals. This research has focused mostly on vaccines, diagnostic methods, epidemiology, and the evolutionary origins of parasites, thanks to the emergence of genomics and proteomics. However, the basic biology of the host–parasite interactions of several important medical and veterinary parasites has not been fully studied. Limited information has been obtained on the intricate neuroimmunoendocrine effects of host–parasite interplay. Therefore, the consequences of these interactions, and their possible therapeutic applications, need to be thoroughly investigated. The chapter reviews the available literature on the host–parasite neuroimmunoendocrine network and discusses how this basic research can be used to design new treatments using hormones, anti-hormones, and hormone analogues as a novel therapy against parasitic diseases. In addition, these studies may also contribute to identifying alternative treatments for parasitic diseases in the future. The complex immuneendocrine network may also help in explaining the frequently conflicting results observed in infections with regards to host sex and age and offer helpful insight into other research avenues besides parasite treatment and control strategies. Finally, several natural products isolated from plants, used in traditional medicine, offer an alternative approach for natural products in the preparation of inexpensive and effective antiparasitic drugs.

Section 2 includes four chapters. Chapter 6, "Perspective Chapter: Parasitic Platyhelminthes Nuclear Receptors as Molecular Crossroads" by Adriana Esteves and Gabriela Alvite, discusses research directed at identifying the nuclear receptors (NRs) set expressed by parasitic platyhelminths. Important gaps concerning NRs mechanism of action, ligands, co-regulator proteins, and DNA binding sequences on target genes need to be addressed. Several in vitro effects of host steroid hormones on *Taenia* and *Echinococcus* species have been observed, but the classical mammalian estrogen, androgen, or progesterone receptors couldn't be identified in databases. Nonetheless, novel nuclear receptors and related proteins and genes are being identified and characterized. The elucidation of NRs gene targets as well as ligands in parasitic platyhelminths could allow for the discovery of new and specific pathways differing from those of their hosts. In this sense, these parasitic proteins seem to be good putative targets of new drugs.

Chapter 7, "Perspective Chapter: Molecular Crosstalk and Signal Transduction between Platyhelminths and their Hosts" by Ednilson Hilário Lopes-Junior et al., highlights that parasitic infection is an intimate relationship between host and parasites with an exchange of signal and complex signaling systems involved in these organisms' molecular crosstalk. With the advances of knowledge due to the genomic and transcriptomics projects in the last decades, several genes and the molecular mechanism involved in the biological function of platyhelminths have been described. Cytokines, hormones, and other molecules from the host have influenced the growth, development, and reproduction of platyhelminths. Thus, the authors review the effects of host cytokines (IL-1, IL-4, IL-12, IL-7, TGF-β, TNF-α) and hormones (T4, estrogen, progesterone, and androgens) that directly or indirectly affect parasite development and reproduction and the possible associated signaling pathways.

Chapter 8, "Helminths Derived Immune-Modulatory Molecules: Implications in Host-Parasite Interaction" by Das et al., points out that the parasitic life cycle of helminths greatly relies on sophisticated manipulation of the host environment and successful evasion of the host defense. Helminths produce a repertoire of secretory molecules (extracellular vesicles and/or exosomes) to invade and generate habitable host environments and modulate the host immune responses in such a way that ensures their prolonged survival within the host. The authors present an outline on helminths derived immune-modulatory molecules and their implications in host–parasite crosstalk.

Chapter 9, "Oxygen and Redox Reactions Contribute to the Protection of Free-Living and Parasite Helminths against Pathogens and/or Host Response" by Agustin Plancarte and Gabriela Nava discuss how millions of years ago, the reductive atmosphere environment of Earth was replaced by an oxidative one as a result of oxidation-reduction reactions (redox reactions), which increase the concentration of oxygen. These oxidative conditions allowed aerobic organisms to populate the planet, which acquired mechanisms to both control the toxicity of oxygen and obtain from it via redox reactions energy, both situations, through their aerobic metabolism. In addition, aerobic organisms began to produce reactive oxygen species (ROS) via redox reactions of oxygen molecules. In aerobic organisms, some ROS such as H2O2 function as second messengers in cell signal transduction, allowing for the development of metabolic processes, including gene control. Free-living helminths appeared in the early Paleozoic era and parasite helminths appeared later in the same era. Because of their ancient origins, these organisms represent an excellent research area for biological models. Freeliving helminths, such as *Caenorhabditis elegans* and earthworms, have been used as host models to understand their micro pathogen defenses, particularly those associated with ROS. The chapter discusses the evolution of oxygen molecules and redox reactions, as well as of Earth's atmosphere, and changes over time in the protection mechanisms of helminths.

Section 3 includes three chapters. Chapter 10, "Toxocariasis: From a One Health Perspective" by Fernando Alba-Hurtado and Marco Antonio Muñoz-Guzmán, discusses toxocariasis, which is a neglected zoonotic infection caused by the nematodes *Toxocara canis* and *Toxocara cati*. The distribution of the disease is worldwide and mainly affects dogs and cats. Its larval stage can cause human infection with serious repercussions on the health of its hosts. The infection causes developmental delays, digestive disorders, nonspecific nervous manifestations, and occasionally death associated with hyperparasitosis in some puppies and kittens. In humans, the infection produces clinical syndromes known as visceral larva migrans (VLM), ocular larva migrans (OLM), neurotoxocarosis, and covert toxocariasis. The close contact of people with their pets and the environmental conditions that favor the transmission of this disease place it within the context of one health. The One Health concept is defined as the collaborative efforts of multiple disciplines (medical personnel, veterinarians, researchers, etc.) that work locally, nationally, and globally to achieve optimal health for people, animals, and the environment. From this perspective, toxocariasis is a study model in which classic and recent knowledge of the medical and veterinary area must be combined for its full understanding, with a goal of establishing integrative criteria for its treatment, control, and prevention.

Chapter 11, "*Schistosoma* Hybridizations and Risk of Emerging Zoonosis in Africa: Time to Think of a One Health Approach for Sustainable Schistosomiasis Control and Elimination" by Zacharia et al., discusses the current control of human schistosomiasis in Africa, which is based on preventive chemotherapy and whereby populations are mass-treated with the anthelminthic medication praziquantel. The World Health Organization (WHO) has set a goal of eliminating schistosomiasis as a public health problem and, ultimately, eliminating transmission in all countries where schistosomiasis is endemic by 2030. However, recurrent hybridization between *Schistosoma* species is an emerging public health concern that has a major impact on distribution of the disease and ultimately may derail elimination efforts. The One Health approach recognizes interconnections between the health of humans, animals, and the environment, and encourages collaborative efforts toward the best outcomes. Thus, this chapter explains how the One Health approach can accelerate the control and elimination of schistosomiasis in Africa.

Chapter 12, "Dancing in a Cycle: Global Health Agenda and *Schistosomiasis* Control in Africa" by Adetayo Olorunlana, discusses that schistosomiasis and other NTDs affect about 2 billion people globally. Africa shares approximately 90% of the global burden of schistosomiasis disease. Despite, WHO efforts to control the disease, it remains neglected in most African countries. Control programs exclude adults in Mass Drug Administration (MDAs), and water, sanitation, and hygiene (WASH) because the drug praziquantel is used for treatment. However, migratory patterns of the neglected population and the interplay of social, economic, political, and cultural factors have introduced the disease into previously eliminated and/or new areas. The question is whether Africa can achieve the new goals of the WHO NTDs 2021–2030 Roadmap for schistosomiasis elimination. The chapter compares and contrasts Africa's current topdown approach to schistosomiasis control to a dynamic approach. Or if the previous pattern of late implementation, dependent on only one drug and shifting focus to other diseases of relevance continues. If a new approach is not adopted the dance in the cycle has just begun.

Section 4 includes five chapters. Chapter 13, "Perspective Chapter: Integrated Root-Knot Nematodes (*Meloidogyne*) Management Approaches" by Ahmad et al., describes the *Meloidogyne* genus, which contains the most prevalent and harmful worms formally known as root-knot nematode species. They attack a wide range of plants belonging to different plant families. In the infective second stage, juveniles (J-II) feed on the plant's roots and, as a result, the host plant roots become swollen/produce galls. The attack plant shows stunted growth and in extreme cases the plant dies. An integrated pest management (IPM) approach is required to tackle these harmful nematodes spp. The integrated tactics include cultural/agronomic practices as well as biological and chemical control. A sole management method is not enough to deal with the root-knot nematode. Therefore, a proper IPM package is required for the farmer to gain good health for the crops.

Chapter 14, "Perspective Chapter: The Potential Role of Nematode Parasites in Wildlife Decline – Evidence from Allegheny Woodrats (*Neotoma magister*), Northern Flying Squirrels (*Glaucomys sabrinus*) and now the Eurasian Red Squirrel (*Sciurus vulgaris*)" by Carolyn Mahan and Michael Steele points out that global climate change and human-induced habitat loss alter the landscape for

native wildlife, resulting in shifts in geographic ranges, occupation of smaller, remnant habitat patches, or use of novel environments. These processes often lead to sympatry between species that historically occupied non-overlapping ranges and habitats. Such interactions may result in increased competition for resources and expose species to novel parasites that adversely affect a species' fitness, leading to wildlife declines. The chapter explores these interactions in two species of endangered North American rodents: Northern flying squirrels (*Glaucomys sabrinus*) and Allegheny woodrats (*Neotoma magister*). Northern flying squirrels are declining in the eastern United States due to competition with its congener, southern flying squirrels (*Glaucomys volans*). Increasing evidence indicates that this competition is mediated by a shared intestinal nematode, *Strongyloides robustus*. Transmission of this nematode to the endangered northern flying squirrel may be increasing due to habitat loss, forest fragmentation, and climate change. Climate change causes the northward range expansion of southern flying squirrels and adversely affects the health of coniferous forests, which is the preferred habitat of northern flying squirrels. The chapter authors also note the most recent discovery of *S. robustus* as a factor in the decline of the European red squirrel (*Sciurus vulgaris*). *S. robustus* is a novel parasite to this host in Europe and was introduced along with the invasive eastern gray squirrel (*Sciurus carolinensis*) that is native to North America. Likewise, in Allegheny woodrats, shrinking habitat and landscape changes have resulted in increased range overlap with raccoons (*Procyon lotor*), which harbor a nematode fatal to woodrats. The chapter also discusses the subsequent transmission of this nematode, *Baylisascaris procyonis*, to woodrats as a contributing factor to their decline throughout the Appalachian Mountains.

Chapter 15, "Soil-Transmissible Helminths Infections; Diagnosis, Transmission Dynamics, and Disease Management Strategies in Low-and Middle-Income Countries" by James-Paul Kretchy, examines soil-transmissible helminthes (STHs) infections, which are among the most common sanitation-related public health problems among people living in poor settlements of tropical and subtropical regions in low- and middle-income countries (LMICs). Though available data suggest occurrence of disease in adults, children of school-going age bear the greatest burden, as these infections affect their cognitive development and physical growth. The characteristic high levels of poverty, poor environmental hygiene, open defecation practices, and inadequate sanitation and waste management systems expose residents to the risks of STH infections. Walking bare-footed, inappropriate hand hygiene behavior, and the unavailability/ improper use of personal protective equipment (PPE) can impact transmission risks in endemic communities and among occupational risk groups. These must be properly investigated and managed, and appropriate interventions must be communicated to decision-makers.

Chapter 16, "Zoonotic Trematode Infections; Their Biology, Intermediate Hosts and Control" by Henry Madsen and Jay R. Stauffer, Jr., point out that many diseases linked with trematodes are zoonotic, including liver flukes (*Fasciola spp*., *Clonorchis*, and *Opistorchis* are the most common), intestinal flukes (some species of *Heterophyidae*), lung flukes (*Paragonimus* spp.), and the blood flukes (*Schistosome* species). A characteristic of all these species is that they have a vertebrate as the final host and

freshwater snail species as the first intermediate host. The foodborne trematodes also have a second intermediate host where their infective stage (metacercariae) lodge or in case of the Fasciolidae, cercariae encyst on aquatic or semi-aquatic plants. The chapter describes the biology of transmission with emphasis on the intermediate snail hosts and their control.

Chapter 17, "Biology of the Human Filariases" by Jesuthas Ajendra, Achim Hoerauf, and Marc P. Hübner discusses filarial nematodes, which are parasitic worms transmitted by blood-feeding insects. They cause some of the most debilitating infectious diseases known to humankind. Mainly found in tropical and subtropical areas of the developing world, diseases such as lymphatic filariasis and onchocerciasis represent major public health issues. With millions of people infected and billions at risk of infection, these diseases can stun economic growth and impair quality of life of the affected regions. As such, the WHO has classified both lymphatic filariasis and onchocerciasis as NTDs. The lesser-known filarial disease loiasis not only affects millions of people, but also represents a huge obstacle during mass drug administration programs targeting other filarial diseases. Even less is known about mansonellosis, potentially the most widespread of the human filariases but underestimated due to the lack of clinical symptoms. Large-scale intervention as well as mass drug administration programs are undertaken with the long-term goal of eliminating filarial diseases, as declared in the WHO roadmap 2021–2030. However, there is still neither a vaccination nor short-term macrofilaricidal treatments available. Many drugs have side effects or are not suitable for all patients and thus there are still billions of people living in areas with a high risk of infection.

Section 5 includes two chapters. Chapter 18, "Perspective Chapter: Advances in the Development of Anti-*Trichinella spiralis* Vaccine, Challenges, and Future Prospective" by Aleem et al., discusses trichinellosis, which is a very important foodborne zoonosis caused by *Trichinella spiralis*. This is an important disease and its causative agent is prevalent throughout the world (cosmopolitan). More clinical awareness of trichinellosis is required due to its many outbreaks and the increase in the consumption of pork meat and its byproducts. Trichinellosis is epizootic in nature and its economic burden is associated with the prevention of this disease from the human food chain. This disease is transmitted from animals to humans through the consumption of raw or undercooked meat containing encapsulated muscle larvae of *T. spiralis*. This chapter demonstrates the direct effect of progesterone (P4) and mifepristone (RU486) on the progesterone receptors of *T. spiralis*. It also examines the challenges in the preparation of DNA and recombinant protein vaccination to control trichinellosis.

Finally, Chapter 19, "Perspective Chapter: Multi-Omic Approaches to Vaccine Development against Helminth Diseases" by Daga et al., discusses the need for protective vaccines for humans and livestock against helminth diseases. The "-omics" era has led to renewed interest in vaccine development against helminth diseases, as candidate vaccines can now be designed, evaluated, and refined in a fraction of the time previously required. In this chapter, the authors describe and review genomic, transcriptomic, and proteomic approaches to the design of vaccines against helminth diseases.

We hope that readers find this book helpful and informative. It is our attempt to compile novel and important information about diseases and parasites that are a health burden in underdeveloped countries and an emerging health problem in developed ones.

#### **Jorge Morales-Montor**

Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico


**9. Conclusions**

**Administrator**

Visitor

**Table 13.**

**Table 14.**

**124**

*Opinions of the BOSS effect.*

*Opinions of participants.*

**Category Overview**

and experience).

supply and demand.

possible.

in the shelter for the first time.

information at the headquarters was significant.

*Natural Hazards - Impacts, Adjustments and Resilience*

look at two ahead and work based on the progress situation.

regular reports and quick support from the headquarters.

efficiently with the conductor looking ahead to a few hands.

consideration of priority and difficulty.

equipment purchases and expenditures to residents.

information that cause the waiting are eliminated.

• As the person in charge of the command confirms, the next work to be done is precise, and if there is a shortage or mistake in the work I did, it will be pointed out immediately and as a position to engage

• It is easy to understand because it is organized into a workflow, and the activities arc organized. Also, since the start and end can be discriminated by color, there is a little omission of what to do. • Because everyone sees one workflow, I felt that I could act with the same purpose. Also, I felt that the quickness and efficiency of contacting the headquarters increased, and that the collection of

• While confirming the overall flow chart, I gave work instructions, and if there was room, I could

• The instructions from the leader of the BOSS team were clear, I have followed them strictly, there

• The fact that the evacuation shelter's operation status is known at the headquarters, leads to a sense of security at both the headquarters and the evacuation shelter. It will lead to the simplification of

• When preparing for the shelter's opening, the BOSS team seemed to be conducting instructions

**Quality** • Q depends on (1) priority of work and (2) difficulty of work (necessity of qualification

**Cost** • C depends on (1) operations that require a large number of human resources, and (2)

**Delivery** • D depends on (1) process length, (2) stagnation between processes, and (3) gap between

• Based on this, we will provide the necessary support concerning the effective allocation of staff. Concerning the assignment of tasks to support staff from other local governments, a system will be created to secure and allocate human resources in

• It is a work that requires a large number of workers, such as the operation of shelters, management of supplies, emergency risk assessment of buildings, and building disaster investigation. The load analysis of the entire work is performed to determine the concentration and distribution of personnel. Secure financial resources for processing government expenditure (other than personal expenses). Or try to minimize spending. The evaluation of cost-effectiveness due to advanced measures is also related to this.

• To understand whether the work period ends in a short time frame or takes a long time frame to improve the bottleneck. For operations that require an extended period, such as restoration and reconstruction, building an organizational system based on this is

• For the waiting between processes, the difference between the end and the start of each process is discovered, and the shortage of personnel, materials/equipment, and

• The demand difference between supply and demand is that the need disappears due to the difference between the demand generation timing and the actual supply time point. It is the situation that supplies cannot be kept due to the changing needs of supplies.

was no confusion about what to do at the site, and a smooth setup was possible.

• The workflow of the evacuation shelter is chronological, so it is easy to grasp.

• The staff is older than the leader, but the leader gave appropriate instructions.

This study compared and verified the disaster response process management system BOSS activities, or without BOSS, the manual for evacuation shelter management operations under COVID-19. Two experiments were conducted to clarify the effects and issues of using the BOSS.

As a result, by utilizing the BOSS, the leader gave instructions to the members to clarify their roles. The members shared the work efficiently without duplication, waiting for instructions, and what to do next. The BOSS team had little waiting time (retention) without hesitation about what to do, there were few omissions of work, and many kinds of works were completed during the experiment time compared to the manual team. The leader's remarks were instructed and commanded for the members. It was also found that even young leaders who have no actual disaster response experience can take the minimum response by checking the BOSS workflow.

It was also found that it is necessary to include the minimum required functions in the BOSS. It was also found that it is necessary to devise ways to mechanically check important functions matters on the system, such as creating a checklist.

**References**

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[13] Yuta Yamada et al., To establish a method for creating a disaster response work manual based on normal work, Proceedings of the Institute of Social Safety Science, 10, pp.67–76, 2008.

[14] Takeyasu Suzuki and Masakazu Amami, Development of disaster response management system for local governments and its application to disaster response training, Proceedings of the Japan Society of Civil Engineers Earthquake Engineering, pp. 781–790,

pp.659–664, 2013.

*Disaster Management Process Approach: Case Study by BOSS for Disaster Response under…*

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[3] Kazuko Ueyama et al. Current status

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of Niimi Public University as an evacuation center due to heavy rain disaster in July 2018 and implications for the future, Bulletin of Niimi Public University, 39, pp.185–187, 2018.

Faculty of Education, Ibaraki University, 65, pp.425. -435, 2016.

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**127**

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[6] Izumikawa, K., Infection control after and during natural disaster, Acute Medicine & Surgery, 6, pp.5–11, 2019.

tsunami, Epidemiology and Infection,144(4),pp.787–95, 2016.

[7] Kawano, T., Tsugawa, Y., Nishiyama, K., Morita, H., Yamamura, O., & Hasegawa, K., Shelter crowding and increased incidence of acute respiratory infection in evacuees following the Great Eastern Japan Earthquake and

Institute (CESifo), Munich

om/ajw/articles/13652103

As a future issue, it is possible that omissions will occur if the BOSS is not entered as a workflow.


**1. Introduction**

Cystic fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane conductance regulator (*CFTR*) gene, a cAMP-regulated anion channel. While our knowledge of CFTR function has advanced greatly since the discovery of the gene in 1989, CF remains fatal [1, 2].

© 2015 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

While CF is a multi-organ system disease, most people with CF die of progressive lung disease that begins early in childhood and is characterized by chronic bacterial infection and inflam‐ mation [2]. Nearly 90% of CF patients have at least one copy of the ΔF508 mutation, but there are >2,000 disease causing mutations that result in a range of disease severities [2]. These mutations can be divided into six classes based on the type and consequence of the mutation (Table 1): class I, no synthesis; class II, defective processing; class III, defective regulation; class IV, altered conductance; class V, reduced synthesis; and class VI, accelerated turnover [3]. However, new mutations continue to be identified and one mutation may fit into more than one category by disrupting CFTR transcription, protein trafficking, or protein regulation in more than one way. Pharmacologic approaches aimed at activating alternative ion transport pathways [4-7], reducing inflammation [8, 9], and inhibiting or eliminating bacterial infection [10, 11] are active areas of therapeutic development. There is also intense interest in identifying interventions that might restore function to the mutant protein [5, 6, 12, 13]. The promise of restoring function to mutant protein was recently validated in a clinical trial for the CFTR conductance mutation G551D present in 2%–3% of CF patients [6]. However, unlike small molecule potentiators or correctors, a CFTR gene replacement approach would be efficacious regardless of the disease causing mutation and is potentially a single dose, life-long curative therapeutic strategy for a devastating disease.

**Table 1.** Six classes of mutations in CFTR that result in CF disease [3, 14, 15].

There are a great number of vector options for *CFTR* gene delivery. Non-integrating viral vectors (i.e., adenovirus or adeno-associated virus) and non-integrating nonviral vectors (i.e., plasmid DNA or *in vitro* transcribed RNA) each have important attributes and have resulted in significant advances in the CF gene therapy field (reviewed in [16-18]). However, potential limitations to these episomal expression systems may include gradual decreases in transgene expression over time and limiting host immune responses following vector readministration. These pitfalls could be avoided if a therapeutic transgene is stably integrated into the genome of a progenitor cell population. Thus, in this chapter, we focus on the use of integrating vectors for gene delivery, although some of the topics covered will be relevant to multiple vector systems.

This chapter discusses the common and emerging options for integrating vectors and efforts to deliver integrating vectors to CF animal models. Defining "curing CF with gene therapy" is not nearly as simple as it appears at first glance. As such, we explore a variety of relevant outcome measures. In addition, there are challenges that need to be taken into consideration for pre-clinical and clinical *in vivo* studies, such as: delivery, efficiency, persistence, the potential for insertional mutagenesis, and cell types to transduce.


*2.2.1 Evolution-based*

Evolutionary Algorithm (EA) [25], Differential Evolutionary (DE) [23], Genetic Algorithms (GAs) [25], Pattern Search (PS) [21], Simulated Annealing (SA) [26], Improved Shuffled Complex Evolution (ISCE) [27], Repaired Adaptive Differential Evolution (Rcr-IJADE) [28].

## *2.2.2 Physic-based*

Electromagnetic Field Optimization (EFO), Gravitational Search Algorithm (GSA), Electromagnetism-Like Algorithm (EMA), Weighted Superposition Attraction (WSA) [29].


*3.2. Ethambutol—Target: Arabinogalactan*/*LAM*

*Discovery.* Ethambutol ((+)-2,2- -(ethylenediimino)di-1-butanol, EMB) was discovered at the Lederle Laboratories division of the American Cyanamid Company in New York (USA) in 1961. During a random screening of synthetic compounds in mice, *N***,***N*- -diisopropylethylenediamine was found to protect mice from an *M. tuberculosis* infection. Following an intensive campaign of structure–activity relationship (SAR), ethambutol, a di-hydroxylated derivative of *N***,***N*- -diisopropylethylenediamine, was synthesized [93–95]. Its activity against *M. tuberculosis* in infected mice was four times more potent than streptomycin and protected mice infected with streptomycin- or isoniazid-resistant *M. tuberculosis* strains.

*Activity and toxicity.* EMB is water soluble (solubility 7.58 g/L) and easily taken up by *M. tuberculosis* [96]. EMB is bacteriostatic, with a MIC ranging from 5 to 34 μm against *M. tuberculosis*. EMB is a first-line TB drug, given for the first two months of TB treatment alongside INH, RIF and PZA. EMB adverse effects include liver and ocular toxicity (decreased vision, color blindness) although these effects are reversible once EMB treatment is stopped [97].

*Mode of action.* The target of EMB has not been definitively determined. It was initially thought that EMB inhibited the synthesis of metabolites needed for *M. tuberculosis* replication [96] or hampered RNA synthesis [98]. A set of studies in *M. smegmatis* determined that EMB treatment resulted in the inhibition of mycolic acid transfer to the cell wall [99]; the cellular accumulation of TMM, TDM and free mycolic acids [100]; the inhibition of D-arabinose incorporation into the arabinogalactan complex and arabinomannan [101]; and the accumulation of DPA [102], the arabinose donor in the synthesis of arabinan [103]. While the synthesis of arabinan for the arabinogalactan complex was completely inhibited by EMB, EMB only partially inhibited the synthesis of the arabinan of LAM [104], leading to the conclusion that EMB inhibited different arabinosyl transferases responsible for the formation of arabinan in the cell wall [105].

Recently, EMB was postulated to target the glutamate racemase, MurI (Rv1338) [106]. MurI racemizes L-glutamate to D-glutamate, which is required for peptidoglycan biosynthesis. In an enzymatic assay, EMB partially inhibited the MurI racemisation reaction. Docking experiments suggested that EMB could bind to MurI and act as a competitive inhibitor of MurI substrate. Further experiments are required to confirm the role of MurI in *M. tuberculosis* inhibition by EMB.

*Resistance.* Characterization of EMB-resistant *M. tuberculosis* clinical isolates revealed a connection between EMB resistance and a cluster of genes (*embCAB***,** *Rv3793***–***3795*) [107,108] encoding arabinosyltransferases involved in the biosynthesis of the mycobacterial cell wall arabinan [109]. Initially, the most common mutations found in EMB-resistant but not in EMB-susceptible clinical isolates were at position 306 of *embB* (M306I, M306V and M306L) [107]. When the *embB* mutations M306L, M306V and M306I were introduced into wild-type *M. tuberculosis* strains, the resulting strains

were found to be EMB-resistant, suggesting that the *embB* mutations were a molecular marker for EMB resistance [110,111]. However, *embB* mutations were found in EMB-susceptible clinical isolates, leading to questioning the role of *embB* in EMB resistance [112–115]. Additionally, EMB-monoresistant clinical isolates did not harbor mutation in *embB*, suggesting a different target for EMB [113]. EMB-susceptible strains carrying *embB* mutations were resistant to other antituberculosis drugs pointing to the *emb* locus as a marker for MDR or XDR *M. tuberculosis* strains [110,112,115].

Safi and colleagues have postulated that the high-level EMB resistance found in clinical isolates was a result of an accumulation of various mutations, each individually causing a low-level resistance to EMB but together provided a high degree of resistance [110]. The authors demonstrated that, in vitro, a stepwise introduction of specific mutations in *embB***,** *Rv3806c* (*ubiA*) and *embC* in *M. tuberculosis* led to a strain 8-fold more resistant to EMB than wild-type *M. tuberculosis*. *ubiA* encodes a DPPR synthase involved in DPA biosynthesis. Mutations in *ubiA* increase intracellular DPA levels, which might bind to Emb, leading to EMB resistance [116]. However, the role of *ubiA* in EMB resistance is questionable since mutations in *ubiA* are found in both EMB-susceptible and EMB-resistant *M. tuberculosis* clinical isolates [117].

*Area of investigation.* SAR on ethambutol was performed to improve EMB antimycobacterial activity while reducing its toxicity. The outcome was SQ109, a compound now in phase 2 clinical trial, and with a very different mechanism of action than EMB (see below).


**1. Introduction**

Pharmacovigilance is a necessity in any healthcare setting [1]. Adverse drugs reactions (ADR) reporting, a major part of pharmacovigilance, is either not reported or under-reported in different settings all over the world [2]. Number of ADR reports received by a national pharmacovigilance centre reflects how effective the pharmacovigilance systems are, within the country [3]; it is the role of regulatory agencies which are either part of Ministries of Health or parastatals within such ministries to ensure the quality, safety and efficacy of medicines that are approved by National Regulatory Authorities (NRA), thus, protecting the health of the population. Development of effective systems to mitigate gaps due to low level of pharmacovigilance in the healthcare system so as to enhance ADR reporting by both healthcare workers and patients is important [4].

It should be emphasized that policy development and enforcement of implementation of such policies are important and integral role of Ministry of Health through their departments such as the Namibia Medicines Regulatory Council (NMRC), South Africa Health Products Regulatory Agency, Medicines Control Authority of Zimbabwe, etc.

Using Namibia as an example, the number of ADR reports received by the Therapeutic Information and Pharmacovigilance Centre (TIPC) is relatively low in comparison to the population [5]. This is not in line with the stated number of reports that should be submitted to WHO Upsala Monitoring Centre (WHO-UMC), i.e. 200 reports per 1,000,000 population; with an assumption that a country with a population similar to Namibia should be reporting at least 400 ADRs per year. Below is a figure showing the number of ADR reports submitted to NMRC between 2009 and 2019.

According to Kiguba et al. [6], health systems in low- and middle-income countries (LMICs) are fragile, this is reflected in the capacity of pharmacovigilance structures available within the health systems. As highlighted earlier, the number of ADR reports submitted to pharmacovigilance centres is an indication of the strength of that system. Some of the factors associated with observed challenges facing pharmacovigilance centres and invariably, the structures, which include,

### **1.1 Linking the unlinked**

According to Adenuga et al. [5], it is imperative to develop effective links between stakeholders within the healthcare system and outside it so as to achieve the goal of effective pharmacovigilance. Below is a conceptual framework developed by the authors. The central theme is focused on patients. Effective pharmacovigilance of medicines is part of the Sustainable Development Goals (SDGs) [7].

#### *Embracing the Changing Needs for Pharmacovigilance in Africa DOI: http://dx.doi.org/10.5772/intechopen.106356*

(Adapted from Adenuga et al. [5]. Conceptual framework for effective stakeholder engagement for pharmacovigilance in a resource limited setting)

Funding of health programs has been a bane of developing the healthcare system in some developing countries [8, 9], with most funding coming from donor organisations such as United States Agency for International Development (USAID), FHI 360, Bill and Melinda Gates Foundation and other similar organizations [10, 11]. An example is the establishment of the Pharmacovigilance Centre in Namibia through funding from USAID.

Marketing Authorisation Holders (MAH) of registered medicines can be engaged in patient management with regard to pharmacovigilance, especially, with respect to the applicants who register generic products, might assist in better pharmacovigilance of such medicines or products.