2.1. Participants and Study Design
inflammation
INFLAMMATION, OXIDATIVE STRESS, DISEASES, ADVERSE EFFECTS
The primary aim of the present trial in healthy human volunteers was to assess the effect of MedDiet with or without MAB juice for two weeks on lipid and glycemic blood profiles. The second aim was to examine the effect of MedDiet with or without MAB juice on the inflammasome and oxidative stress, by assessing changes in transcript levels of 7 related genes. Thirty healthy volunteers were consecutively recruited among the population of subjects belonging to the Section of Clinical Nutrition and Nutrigenomics, Department of Biomedicine and Prevention of the University of Rome Tor Vergata, Italy, for a routine medical check-up program [Exclusion criteria included the presence of one or more of the following diseases: acute or chronic metabolic/diabetes/intestinal, cardiovascular/liver/kidney, autoimmune, HIV/AIDS/COVID-19/cancer. Pregnant and lactating women, and anyone taking any type of medication or supplement or following a specific diet were excluded.Exclusion factors also included frequent or daily consumption of flavonoid-rich beverages such as tea, herbal teas, coffee, cocoa, and fruit juices exceeding 500 mL (as estimated by the food frequency questionnaire).Finally, twenty-four subjects (sixteen female) completed the study.Three enrolled subjects did not meet the inclusion criteria: one had a BMI < 19 Kg/mThe sample size was considered adequate to achieve 95% statistical power for detecting a difference in Fold Change value (FC) gene expression of >1.5.A randomized crossover, controlled study design, with two arms of dietary treatment, was used: arm (1) MedDiet: carbohydrates 55–60% of total Kcal; protein 15–20% of total Kcal of which 50% plant-derived; total fats <30% of total Kcal; saturated fat <10% of total Kcal; polyunsaturated fatty acids (PUFA) 6–10% of total Kcal: 5–6% of total Kcal from n-6 PUFA, and 1–2% of total Kcal from n-3 PUFA; MUFA about 15% of total Kcal; trans-fatty acids <1% of total Kcal; 30 g of fiber; oxygen radical absorbance capacity (ORAC) > 5000 µMolTe; arm (2) MedDiet + 250 mL/day of MAB juice (MedDiet + MAB juice).During the study period, enrolled volunteers were randomly assigned to group A following the MedDiet; group B following the MedDiet + MAB juice. After each 2-week dietary intervention, a wash-out of 3 weeks was followed to prevent additive effects on the next treatments. After the wash-out period, the 2-week dietary treatment of the two groups was reversed, as shown in MAB juice was made by the research team and distributed to enrolled volunteers.At baseline, an assessment of nutritional status was performed, based on the collection of anthropometric parameters and body composition. Samples for biochemical analysis and genomics evaluation with an analysis of seven genes belonging to oxidative stress and inflammation pathway were collected at baseline and after 2 weeks of MedDiet and MedDiet + MAB juice.Participants were not blinded to the type of juice they consumed.Participants were aware of the type of treatment. They were asked not to change their lifestyle and to note any changes during the study. Clinicians assessed any adverse effects and symptoms that were possibly associated with the interventions. No abnormality was presented during the study period.Informed consent was signed by all participants, by the principles of the Declaration of Helsinki. This trial is registered with ClinicalTrials.gov NCT01890070. The approval of the study was obtained by the Ethics Committee of the Calabria Region Center Area Section (Register Protocol No. 146 17/05/2018). This research received no external funding. All the costs for the entire research protocol and the clinical trial were covered by the own funds of the Clinical Nutrition and Nutrigenomics Section of the Department of Biomedicine and Prevention, deriving from cost savings.