Effects of fenugreek supplementation on the components of metabolic syndrome: A systematic review and dose-response meta-analysis of randomized clinical trials.

Metabolic syndrome (MetS) is a cluster of metabolic disorders with a heavy disease burden. Fenugreek was reported to be effective in some components of MetS. Therefore, a comprehensive review and meta-analysis of randomized controlled trials was conducted to study the effects of fenugreek on MetS indices. From the beginning until August 2022, PubMed, Embase, Scopus, and Web of science were searched. Data were analyzed using the random-effect model, and presented as weighted mean difference (WMD) and associated 95 % confidence interval (CI). This meta-analysis comprised from a total of 29 eligible RCTs with 31 arms measuring fasting plasma glucose (FPG), Triglyceride (TG), high-density lipoprotein (HDL), waist circumference (WC), systolic blood pressure (SBP), and diastolic blood pressure (DBP). The results indicated significant improving effects of fenugreek on FPG (WMD: -16.75 mg/dL; 95 % CI: -23.36, -10.15; P < 0.001), TG (-20.12 mg/dL; 95 % CI: -34.238, -5.994; P < 0.001), HDL (WMD: 3.55 mg/dL; 95 % CI: 1.98, 5.12; P < 0.001), WC (WMD: -2.51; 95 % CI: -3.78, -1.24; P < 0.001) and SBP (WMD: -3.45 mmHg; 95 % CI: -6.38, -0.52; P = 0.021); However the effect on DBP (WMD: 3.17; 95 % CI: -5.40, 11.73; P = 0.469) and BMI (WMD: -0.40 kg/m2; 95 % CI: -1.114, 0.324; P = 0.281) was not significant. Administration of fenugreek can meaningfully reduce FPG, TG, WC, and SBP and increase HDL. The overall results support possible protective and therapeutic effects of fenugreek on MetS parameters.

Melatonin effectiveness in amelioration of oxidative stress and strengthening of antioxidant defense system: Findings from a systematic review and dose-response meta-analysis of controlled clinical trials.

BACKGROUND AND AIM: Oxidative stress is involved in the development of chronic diseases. It has been suggested that melatonin has a protective role against oxidative stress by activation of antioxidant enzymes and scavenging free-radicals. Present study aimed to investigate the effect of melatonin supplementation on oxidative stress and antioxidant biomarkers such as malondialdehyde (MDA), increased total antioxidant capacity (TAC), superoxide dismutase (SOD), and Glutathione peroxidase (GPx). METHODS: Systematic search was performed to identify relevant studies in PubMed/Medline, SCOPUS, Web of Science and Embase databases and Google Scholar up to September 2020. Meta-analysis was conducted using random-effect model. Subgroup analysis and meta-regression was used to identify sources of heterogeneity. The quality of studies was assessed using Cochrane Collaboration's tool. Publication bias was assessed by visual inspection of funnel plot. RESULTS: A total number of 16 eligible articles were included in the meta-analysis. The dosages of melatonin varied between 3 and 400 mg/day, with a duration range between 1.42 and 12 weeks. Melatonin supplementation significantly increased serum levels of TAC [SMD: 1.59; 95% CI: 0.89, 2.29; P < 0.001; (I2 = 93.53%, P < 0.001 No significant effects were observed on MDA [SMD: -3.09; 95% CI: -7.07, 0.89; P = 0.12; (I2 = 99.57%, P < 0.001)], GPx [SMD: 0.86; 95% CI: -3.46, 5.19; P = 0.61; (I2 = 98.17%, P < 0.001)] and SOD levels [SMD: 1.92; 95% CI: -3.57, 7.41; P = 0.35; (I2 = 98.27%, P < 0.001)]. CONCLUSION: Results of the current meta-analysis showed that melatonin supplementation had a significant impact on attenuating of oxidative stress and enhancing antioxidant performance. Melatonin supplementation could be suggested as a safe complementary approach in amelioration of the chronic diseases.