Effects of chromium supplementation on oxidative stress biomarkers.

Aim: This systematic review and meta-analysis aimed to evaluate the effects of chromium supplementation on oxidative stress biomarkers such as superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GPX), malondialdehyde (MDA), total antioxidant status (TAS), thiobarbituric acid reactive substances (TBARS), catalase (CAT), nitric oxide (NO), total antioxidant capacity (TAC) and protein carbonyl. Methods: Relevant studies, published from inception until July 2019, were searched through PubMed/Medline, Scopus, ISI Web of Science, Embase, and Google Scholar. All randomized clinical trials investigating the effect of chromium supplementation on oxidative stress were included. Results: Out of 252 citations, 10 trials that enrolled 595 subjects were included. Chromium supplementation resulted in a significant increase in GSH (WMD: 64.79 mg/dl, 95% CI: 22.43 to 107.15; P=0.003) but no significant change in MDA, TAS, TBARS levels, SOD, CAT levels and GPX. Chromium picolinate supplementation resulted in a significant increase in TAC while failing to have a significant effect on NO. Moreover, both chromium picolinate and chromium dinicocysteinate supplementation reduced protein carbonyl levels. Conclusion: Overall, this meta-analysis demonstrated that chromium supplementation increased GSH without any significant changes in the mean of GPX, MDA, TAS, TBARS, CAT and SOD.

Administration of dietary antioxidants for patients with inflammatory bowel disease: A systematic review and meta-analysis of randomized controlled clinical trials.

OBJECTIVE: Accumulating evidence has been reported regarding the effect of dietary antioxidants on clinical variables in IBD patients, however, findings are controversial. This systematic review and meta-analysis aimed to investigate effect of dietary antioxidants on clinical variables in patients with IBD or its subtypes. METHODS: We searched PubMed, Scopus, and ISI Web of Science from inception to January 2021 using relevant keywords. Data were pooled by using the random-effect model. All statistical analyses were done using STATA version 14. RESULTS: Our meta-analysis was exclusively done on studies about the effect of curcumin on IBD patients, because limited studies were done on other antioxidants. Curcumin administration resulted in significant increment of clinical remission in patients with IBD (SMD: 0.86%, 95% CI: 0.16, 1.56, p = 0.016), significant remission in clinical symptoms (SMD: -0.96 score, 95% CI: -1.34, -0.57, p < 0.001), and significant increment in endoscopic remission in IBD patients (SMD: 0.51%, 95% CI: 0.16, 0.85, p = 0.004), comparing to control group. Curcumin supplementation also made better clinical response than control group (SMD: 0.74%, 95% CI: 0.22, 1.26, p = 0.005) and also resulted in significant improvement in quality of life of patients with IBD, as compared to control group (SMD: 1.23 score, 95% CI: 0.72, 1.74, p < 0.001). CONCLUSIONS: Our meta-analysis showed that curcumin significantly improved clinical and endoscopic remissions in IBD patients. This supplementation also caused significant reduction in clinical symptoms of IBD patients along with better clinical response and the increased quality of life. Further researches with larger sample size and longer period of intervention are required to evaluate efficacy of dietary antioxidants on clinical variables in patients with IBD.

The effects of hesperidin supplementation or orange juice consumption on anthropometric measures in adults: A meta-analysis of randomized controlled clinical trials.

BACKGROUND: The current evidence-base regarding the effect of hesperidin (a flavanone found in citrus fruits) on body composition is equivocal. OBJECTIVE: We conducted a meta-analysis on the effect of orange juice and/or hesperidin supplementation on anthropometric measures in randomized controlled trials (RCTs). MATERIALS AND METHODS: A systematic search of PubMed and Scopus was performed up to February 2020. The overall estimates and their 95% confidence intervals (CIs) were calculated using a random-effects model. RESULTS: Eleven eligible RCTs, with 512 individuals, were included in this study. The meta-analysis showed that orange juice and/or hesperidin had no significant effect on body weight [weighted mean difference (WMD) = -0.31 kg; 95% CI, -1.44 to 0.82, P = 0.592], body mass index [WMD = 0.11 kg/m2; 95% CI, -0.33 to 0.56, P = 0.617], fat mass [WMD = 0.14 kg; 95% CI, -0.95 to 1.22, P = 0.807], percentage body fat [WMD = -0.70%; 95% CI, -2.58 to 1.18, P = 0.463] and waist circumference [WMD = 0.07 cm; 95% CI, -1.16 to 1.30, P = 0.588]. CONCLUSION: The present study revealed that there is no significant beneficial effect of orange juice and/or hesperidin supplementation on anthropometric measures. The authors advocate that more high-quality clinical trials are needed to better discern the potential efficacy of orange juice and/or hesperidin.

Effects of melatonin supplementation on oxidative stress: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVES: Previous studies showed that melatonin supplementation may suppress oxidative stress, however, the results have not been consistent. So, we conducted this meta-analysis to assess the precise relationship between melatonin supplementation and oxidative stress. METHODS: PubMed and Scopus were searched for randomized controlled trials that investigated the effect of melatonin supplementation on oxidative stress up to March 2020. Heterogeneity was assessed by Cochran's Q test and I-square (I 2) statistic. Data were pooled using the random effect model and standardized mean difference (SMD) was considered as the summary effect size. Also, standard methods were used for assessment of sensitivity analysis and publication bias. RESULTS: We included 15 related articles and our findings indicated that melatonin supplementation significantly increased total antioxidant capacity (TAC) level (SMD: 1.03, 95% CI: 0.24, 1.81, p=0.011) and reduced protein carbonyl (PCO) (SMD: -1.78, 95% CI: -2.97, -0.58, p=0.004) and malondialdehyde (MDA) levels (SMD: -0.94, 95% CI: -1.48, -0.40, p=0.001). Additionally, there was considerable effect on TAC level by using ≥20 mg/d melatonin and in people under 35 years old. MDA level also decreased using dosage of below 20 mg/d and in people ≥35 years old. CONCLUSIONS: The present study showed a promising effect of melatonin administration for reducing MDA, PCO, and increasing TAC levels. However, further studies especially with more attention to PCO level assessment are needed to confirm the findings of the present study in larger samples on different populations.

The effect of chromium supplementation on apolipoproteins: A systematic review and meta-analysis of randomized clinical trials.

BACKGROUND: Apos play a role in lipoprotein metabolism. Several studies have been carried out on the effect of chromium supplement in improving CVD risk factors. OBJECTIVE: This study is a systematic review and meta-analysis that aimed to investigate the effect of chromium supplementation on Apos levels of human studies. MATERIALS AND METHODS: We searched PubMed, Scopus up to May 2020 up to September 2019. We retrieved studies from identified articles. The studies' quality was evaluated using Cochrane Risk of Bias Tool. We estimated the effect of chromium supplementation on Apo A, Apo A1, and Apo B by pooling mean and standard deviation (SD) values. RESULTS: We obtained six trials involving 231 participants. Chromium consumption resulted significantly decreased Apo B while the subjects were ingesting chromium picolinate. Chromium supplementation did not significantly decrease Apo A (WMD: -3.89 mg/dl; 95% CI, -11.96 to 4.18) with no significant heterogeneity (I2 = 0.00%, p = 0.37). The serum level of Apo A1 did not statistically change following chromium intervention (WMD: 6.11 mg/dl; 95% CI, -7.01 to 19.23) with no significant heterogeneity (I2 = 0.00%, p = 0.68). Chromium supplementation did not significantly decrease Apo B (WMD: 3.81 mg/dl; 95% CI, -5.32 to 12.94). With no significant heterogeneity (I2 = 42.3%, p = 0.12). CONCLUSIONS: The chromium supplement did not have a significant effect on the Apolipoproteins (Apo A, ApoA1 and Apo B).

The association of plant-based dietary patterns with visceral adiposity, lipid accumulation product, and triglyceride-glucose index in Iranian adults.

BACKGROUND: We sought to investigate whether adherence to a more plant-based, and less animal-based, diet is associated with visceral adiposity, lipid accumulation product (LAP), and triglyceride-glucose index (TyG) in Iranian adults. METHODS: This cross-sectional study was conducted on 270 adults aged between 18-75 years old. We created three plant-based diets. including an overall plant-based diet index (PDI), hPDI, and uPDI based on tertiles regarding the intake of animal- or plant-based food items obtained from a semi quantitative food-frequency questionnaire. RESULTS: Higher hPDI was significantly associated with lower body mass index (BMI) (P-value = 0.01), lower waist circumference (P-value<0.001), and lower waist-hip ratio (P-value<0.001). A significant increase was found for high density lipoproteins (HDL) (P-trend <0.001) with a significant decrease for LAP (P-value = 0.03) in those with higher adherence to hPDI. Moreover, greater adherence to PDI was associated with a significant increase in diastolic blood pressure (DBP) (p-value = 0.01) and fat free mass (FFM) (p-value = 0.01). There were no significant associations between PDIs and TyG and VFA. CONCLUSION: We found that a higher hPDI score was significantly associated with better anthropometric measurements. A significant increase was found for HDL and a significant decrease was found for LAP on hPDI. However, a higher PDI score was significantly associated with higher DBP and higher FFM.

Effects of berberine and barberry on anthropometric measures: A systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: Despite controversies, no study has systematically summarized findings from earlier studies on the effect of berberine and barberry on anthropometric measures. Therefore, the current systematic review and meta-analysis was conducted on the effect of berberine and barberry on body mass index (BMI), body weight (BW), waist circumference (WC) and waist-hip ratio (WHR) in adults. METHODS: Relevant studies, published up to August 2019, were searched through PubMed/Medline, Scopus, ISI Web of Science, Embase and Google Scholar. All randomized clinical trials investigating the effect of berberine and barberry on the anthropometric measures including BMI, BW, WC or/and WHR were included. RESULTS: Out of 252 citations, 12 trials that enrolled 849 subjects were included. Berberine and barberry resulted in no significant change in BMI (Weighted mean differences (WMD): -0.16 kg/m2; 95 % CI: -0.43 to 0.11, P = 0.247), BW (WMD: -0.11 kg; 95 % CI: -0.13 to 0.91, P = 0.830), and berberine resulted in not significant in WC (WMD: -0.58 cm; 95 % CI: -1.89 to 0.72, P = 0.379) and significant reduction in WHR (WMD: -0.03; 95 % CI: -0.04 to -0.01, P < 0.0001). CONCLUSION: We found a significant reduction in WHR following berberine consumption in adults. Further clinical trials with high quality according to challenges mentioned seem to be helpful to use berberine and barberry as a supplement for certain health conditions, efficiently.