The Effect of HMG-CoA Reductase Inhibitor on Insulin Resistance in Patients Undergoing Peritoneal Dialysis Effects of supplementation with curcumin on serum adipokine concentrations: A randomized controlled trial. Effects of 90-day hypolipidemic treatment on insulin resistance, adipokines and proinflammatory cytokines in patients with mixed hyperlipidemia and impaired fasting glucose.
Background Insulin resistance is associated with the progression of atherosclerosis and is reported to predict cardiovascular mortality in patients with end-stage renal disease ( ESRD ) . Although statins exert pleiotropic effects , it is uncertain whether statin therapy improves insulin resistance in these patients . In this prospect i ve r and omized controlled trial , we aim ed to evaluate the effects of statin on insulin resistance among 70 patients undergoing peritoneal dialysis ( PD ) . Methods Patients were r and omized into a statin group ( n = 35 ) or a control group ( n = 35 ) . The statin group received 10 mg per day of rosuvastatin for 6 months . We determined insulin resistance by homeostatic model assessment of insulin resistance ( HOMA-IR ) index . Serum concentrations of adipokines such as adiponectin , leptin , and resistin were measured using enzyme-linked immunosorbent ( ELISA ) assay . As inflammatory markers , high sensitive C-reactive protein ( hsCRP ) and interleukin-6 were also measured . Results There were no significant differences in baseline characteristics between the two groups . Compared to baseline value , statin treatment significantly decreased HOMA-IR index from 2.37 ± 1.08 to 2.05 ± 0.82 ( P = 0.014 ) . There was a concordant decrease in hsCRP levels in the statin group ( 2.05 ± 1.57 to 1.21 ± 0.84 mg/L , P < 0.001 ) , but such improvements were not observed in the control group . When between-group differences in these parameters were compared , hsCRP levels were more decreased in the statin group than in the control group ( P = 0.021 for between-group difference ) , whereas HOMA-IR index was not ( P = 0.189 for between-group difference ) . During this period , statin treatment did not result in the improved adipokine profiles . Conclusion This study showed that statin therapy failed to improve insulin resistance in PD patients despite a significant decline in hsCRP levels after statin treatment . Our finding suggests that reducing inflammation by statin is of limited help to fully attenuate insulin resistance in these patients OBJECTIVE Previous experimental studies have suggested curcumin as a safe phytochemical that can improve insulin resistance through effects on adiponectin and leptin . This study aim ed to investigate the effect of curcumin on circulating adiponectin and leptin concentrations in patients with metabolic syndrome . METHODS In this pilot , r and omized , double-blind , placebo-controlled trial , subjects who met the criteria of metabolic syndrome according to the National Cholesterol Education Program Adult Treatment Panel III criteria were r and omly assigned to curcumin ( n = 59 ; 1000 mg/d ) or a placebo ( n = 58 ) for 8 wk . Serum adiponectin and leptin concentrations were determined before and after intervention . The pooled effect size for the impact of curcumin supplementation on serum adiponectin and leptin levels was also estimated using r and om-effects meta analysis . RESULTS Eight-week supplementation with curcumin was associated with a significant increase in serum adiponectin levels ( P < 0.001 ) and a reduction in serum leptin concentrations ( P < 0.001 ) . Serum leptin : adiponectin ratio was also improved by curcumin ( P < 0.001 ) . These beneficial effects of curcumin remained significant after adjustment for changes in serum lipids and glucose concentrations and baseline differences in body mass index and serum levels of glucose and glycated hemoglobin as potential confounders of treatment response . Meta analysis suggested that curcumin supplementation can increase adiponectin levels by 76.78 % ( 95 % CI : 6.14 - 147.42 ; P = 0.0330 ) , and reduce leptin by 26.49 % ( 95 % CI : -70.44 to 17.46 ) , however this latter effect size did not reach statistical significance ( P = 0.238 ) . CONCLUSIONS Curcumin can improve serum levels of adiponectin and leptin in patients with metabolic syndrome . This trial was registered at the UMIN Clinical Trials Registry ( http://www.umin.ac.jp/ctr/ ) under Trial No. UMIN000018339 OBJECTIVE Concerns regarding worsening insulin sensitivity associated with statin treatment have recently emerged . Therefore the aim of this study was to assess and compare the effects of 90-day monotherapies with fenofibrate and atorvastatin , as well as combined therapy , on fasting plasma glucose , insulin resistance index , adipokines ( leptin , resistin , adiponectin ) and levels of proinflammatory cytokines ( TNF-α , IL-6 ) in patients with impaired fasting glucose ( IFG ) and mixed hyperlipidemia . MATERIAL S AND METHODS 67 patients were r and omly assigned to four treatment arms : monotherapy with atorvastatin , monotherapy with fenofibrate , combined therapy ( fenofibrate and torvastatin ) or therapeutic lifestyle change . The study lasted for 90 days . All participants received counseling regarding proper diet and physical activity . RESULTS Compared to the control subjects , prediabetic patients exhibited elevated plasma levels of leptin , resistin , TNF-α and IL-6 , and a lower plasma level of adiponectin . All therapeutic interventions result ed in significant alterations in the lipid profile . Insulin resistance index ( HOMA-IR ) was reduced after treatment with fenofibrate . The effect of atorvastatin on insulin resistance was comparable to therapeutic lifestyle change alone . Therapy with hypolipidemic drugs caused increases in adiponectin levels and decreases in leptin and resistin . An additive effect of the combined treatment on plasma IL-6 level was also observed . CONCLUSIONS Fenofibrate-based treatment was associated with improved insulin sensitivity . Atorvastatin did not cause a deterioration in insulin sensitivity . Hypolipidemic therapies result ed in significant changes in the proinflammatory cytokine network as well as in adipokine levels . At the end of the study the measured parameters nearly resembled those of the healthy subjects
There was no association between the duration of statin therapy and changes in plasma leptin levels .
Furthermore , there was no differential effect of hydrophilic and lipophilic statins on plasma leptin concentrations .
OBJECTIVES The effects of statins on insulin sensitivity , metabolic homeostasis and adipokines in humans are controversial .
Several studies have investigated the impact of statin therapy on plasma leptin concentrations but the results have been inconsistent .
The aim of the present study was to conduct a systematic review and meta- analysis of available evidence to calculate the effect size of statin therapy in changing serum leptin concentrations .