Effects of chromium supplementation on body composition in patients with type 2 diabetes: A dose-response systematic review and meta-analysis of randomized controlled trials.

INTRODUCTION: Several randomized controlled trials (RCTs) have demonstrated the beneficial effects of chromium supplementation in managing type 2 diabetes mellitus (T2DM). The current systematic review and meta-analysis aimed to investigate the associations between chromium supplementation and body composition in patients with T2DM. METHODS: To achieve this, PubMed, Scopus, Embase, Cochrane Library, and Web of Science were searched for randomized clinical trials (RCTs) that reported the effects of chromium supplementation on body composition such as body weight (BW), body mass index (BMI), fat mass (FM), and waist circumference (WC) in patients with T2DM from inception until July 2023. Weighted mean differences (WMDs) with 95% confidence intervals (CIs) were calculated using a fixed-effects model. RESULTS: The meta-analysis included a total of 14 RCTs. The results showed that chromium supplementation did not have any significant effect on FM (WMD = -0.43%; 95% CI -0.94, 0.09), BMI (WMD: 0.09 kg/M2, 95% CI: -0.03, 0.20), WC (WMD: -0.47 cm, 95% CI: -1.10, 0.16), and BW (WMD: -0.26 kg, 95% CI: -0.69, 0.16). However, subgroup analysis revealed that chromium intake decreased FM in subjects aged ≥ 55 years and when chromium picolinate was used as an intervention. Additionally, there was a non-linear association between the dose of chromium supplementation and BW. CONCLUSIONS: The meta-analysis suggests that chromium supplementation does not significantly reduce BW, BMI, WC, and FM in patients with T2DM. Further RCTs with large-scale are required to determine the possible anti-obesity effects of chromium in patients with T2DM.

The effects of whey protein on blood pressure: A systematic review and dose-response meta-analysis of randomized controlled trials.

AIMS: This systematic review and dose-response meta-analysis was conducted to summarize data from available clinical trials on the effects of whey protein (WP) supplementation on blood pressure (BP) in adults. DATA SYNTHESIS: A comprehensive literature search was conducted in the electronic databases PubMed, Web of Science, ProQuest, Embase, and SCOPUS from inception to October 2022. Weighted mean differences (WMD) and 95% confidence intervals (CI) were calculated to assess pooled effect sizes. Heterogeneity between studies was assessed using the Cochran's Q test and I2. Subgroup analysis was performed to assess potential sources of heterogeneity. The dose-response relationship was assessed using fractional polynomial modeling. Of the 2,840 records, 18 studies with 1,177 subjects were included. Pooled analysis showed that whey protein supplementation resulted in a significant reduction in systolic blood pressure (WMD: -1.54 mmHg; 95% CI: -2.85 to -0.23, p = 0.021), with significant heterogeneity between studies (I2 = 64.2%, p < 0.001), but not for diastolic blood pressure (DBP) (WMD: -0.27 mmHg; 95% CI: -1.14, 0.59, p = 0.534) with high heterogeneity between studies (I2 = 64.8%, p < 0.001). However, WP supplementation significantly reduced DBP at a dose of ˃30 g/day, in RCTs that used WP isolate powder for their intervention, in sample sizes ≤100, in studies with an intervention duration of ≤10 weeks, and in those studies that were conducted in patients with hypertension and had participants with a BMI of 25-30 kg/m2. CONCLUSION: This meta-analysis demonstrated that WP intake significantly reduced SBP levels. Further large-scale studies are needed to specify the exact mechanism, and optimal dosage of WP supplementation to obtain a beneficial effect on BP.

Effects of luteolin on sepsis: A comprehensive systematic review.

BACKGROUND: Sepsis and septic shock are the main causes of mortality and complications in intensive care units all over the world. Luteolin is thought to have a significant role as a free radical scavenger, an anti-inflammatory agent, and an immune system modulator. The object of this review is to conduct a systematic review of the effects of luteolin and its mechanisms of action in the treatment of sepsis and its complications. METHOD: The investigation was carried out in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines (PROSPERO: CRD42022321023). We searched Embase, Web of Science, Google Scholar, Science Direct, PubMed, ProQuest, and Scopus databases up to  January 2023 by using the relevant keywords. RESULTS: Out of 1,395 records screened, 33 articles met the study criteria. In the collected papers, the main reported findings are that luteolin can affect inflammation-initiating pathways such as toll-like receptors and high mobility group box-1 and reduces the expression of genes that produce inflammatory cytokines, such as the Nod receptor protein-3, and nuclear factor kappa-light chain-enhancer of activated B cells. Luteolin also reduces the overactivity of macrophages, neutrophil extracellular traps and lymphocytes by regulating the immune response. CONCLUSION: Most studies revealed luteolin's positive benefits on sepsis through several pathways. Luteolin showed the capacity to reduce inflammation and oxidative stress, control immunological response, and prevent organ damage (in vivo studies) during sepsis. Large-scale in vivo experiments are necessary to elucidate its potential impacts on sepsis.

Systematic review and meta-analysis of the effect of garlic in patients with non-alcoholic fatty liver disease.

BACKGROUND: We aimed to conduct a systematic review and meta-analyses to examine the therapeutic effect of garlic on non-alcoholic fatty liver disease (NAFLD). METHODS: We searched PubMed, Scopus, Web of Science, and Embase databases for retrieving articles investigating the impact of garlic on NAFLD patients. The comprehensive meta-analysis software version 2.0 was used for statistical analysis. The standardized mean difference with a 95% confidence interval (CI) was reported and the effect size was calculated. RESULTS: A preliminary search yielded a total of 293 articles. After screening articles based on inclusion criteria, four articles were included in the final analyses. This systematic review included 186 patients with NAFLD. The result of the meta-analysis showed significant differences between the garlic and placebo groups regarding changes in alanine aminotransferase, aspartate aminotransferase, total cholesterol, low-density lipoprotein-cholesterol, triglyceride, and fasting blood sugar. Moreover, the probability of a decrease in hepatic steatosis was 2.75 times lower in the garlic group compared with the placebo group (RR [95% CI]: 2.75 [1.79, 4.23], p-value<0.001). CONCLUSION: This meta-analysis demonstrates that garlic supplementation had a positive effect on hepatic steatosis, liver enzyme levels, and metabolic profile of patients with NAFLD. However, considering the potential limitation of the included studies, more high-quality clinical trials are needed.

Co-supplementation of camelina oil and a prebiotic is more effective for in improving cardiometabolic risk factors and mental health in patients with NAFLD: a randomized clinical trial.

This trial evaluated the effects of co-supplementing Camelina sativa oil (CSO) and a prebiotic as modulators of the gut microbiota on cardiometabolic risk factors and mental health in NAFLD patients. In all, 44 subjects with NAFLD were allocated to either an intervention (20 g d-1 CSO + resistant dextrin) or a placebo (20 g d-1 CSO + maltodextrin) group and received a calorie-restricted diet (-500 kcal d-1) for 12 weeks. Fasting plasma levels of gucose, insulin, hs-CRP, endotoxin, antioxidant enzyme activity, total antioxidant capacity (TAC), malondialdehyde (MDA), 8-iso-prostaglandin F2α, and uric acid were measured at the baseline and post-intervention. The depression, anxiety and stress scale (DASS) and the general health questionnaire (GHQ) were used to assess mental health. Co-supplementing CSO and resistant dextrin significantly decreased the level of insulin concentration (-0.84 µU ml-1, p = 0.011), HOMA-IR (-0.27, p = 0.021), hs-CRP (-1.25 pg ml-1, p = 0.023), endotoxin (-3.70 EU mL-1, p = 0.001), cortisol (-2.43, p = 0.033), GHQ (-5.03, p = 0.035), DASS (-9.01, p = 0.024), and MDA (-0.54 nmol mL-1, p = 0.021) and increased the levels of TAC (0.16 mmol L-1, p = 0.032) and superoxide dismutase (106.32 U g-1 Hb, p = 0.45) in the intervention group compared with the placebo group. No significant changes were observed in the levels of other biomarkers. Co-supplementing CSO and resistant dextrin in combination with a low-calorie diet may improve metabolic risk factors and mental health in NAFLD patients.

Omega 3-rich Camelina sativa oil in the context of a weight loss program improves glucose homeostasis, inflammation and oxidative stress in patients with NAFLD: A randomised placebo-controlled clinical trial.

BACKGROUND: Over the past few years, the benefits of omega-3 fatty acids have been reported in the management of non-alcoholic fatty liver disease (NAFLD) complications.This study evaluated the effects of Camelina sativa oil (CSO) supplementation as one of the richest dietary sources of omega-3 fatty acids on glucose homeostasis,inflammation, metabolic endotoxemia, and oxidative stress in NAFLD patients. METHODS: A total of 46 patients with NAFLD were allocated to either an intervention (20 g/d CSO) or placebo (20 g/d sunflower oil) group receiving a calorie-restricted diet for 12 weeks. Fasting plasma levels of glycemic indices, hs-CRP, lipopolysaccharide (LPS), antioxidant enzymes activity, total antioxidant capacity (TAC), malondialdehyde (MDA), 8-iso-prostaglandin F2α (8-iso-PGF2α), and uric acid were measured at baseline and post-intervention. RESULTS: The CSO supplementation led to significant differences in insulin concentration, homeostasis model assessment of insulin resistance (HOMA-IR), hs-CRP, LPS, TAC, superoxide dismutase (SOD) activity, MDA and 8-iso-PGF2α between the two groups at end of the study (ANCOVA, P < .05). Hs-CRP decreased significantly in both groups (pair-t-test, P < .05). Insulin concentration, quantitative insulin sensitivity check index, LPS, TAC, SOD, glutathione peroxidase activity, MDA and 8-iso-PGF2α changed significantly only in CSO group (P < .05). CONCLUSION: These findings indicate that CSO may improve glycemia, inflammation, metabolic endotoxemia, and oxidative stress status in patients with NAFLD.

Changes of body composition and circulating neopterin, omentin-1, and chemerin in response to thylakoid-rich spinach extract with a hypocaloric diet in obese women with polycystic ovary syndrome: A randomized controlled trial.

This trial evaluated the effects of thylakoid-rich spinach extract supplementation combined with a hypocaloric diet on body composition and serum levels of neopterin, chemerin, and omentin-1 in obese women with polycystic ovary syndrome (PCOS). In this randomized controlled trial, 48 obese women with PCOS, aged 20-45 years old, were recruited and randomly divided into thylakoid (n = 24) and placebo (n = 24) groups. They received a low-calorie diet with 5 g/day thylakoid-rich spinach extract or a low-calorie diet with 5 g/day placebo for 12 weeks. The mean age of the participants of the thylakoid group was 31.86 years, and the placebo group was 32.04 years. Thylakoid-rich spinach extract supplementation with a low-calorie diet increased serum levels of omentin-1 (10.90 vs. 3.87 ng/L; p < .001) and decreased fat mass (-5.19 vs. -1.35 kg; p < .001) and serum levels of neopterin (-0.66 vs. -0.38 nmol/L; p = .003) and chemerin (-41.24 vs. -11.26 ng/L; p < .001) in the thylakoid group compared to the placebo group. A significant improvement in omentin-1, chemerin, and neopterin by thylakoid-rich spinach extract supplementation was under the influence of weight change and insulin resistance status throughout the study. A significant decrease in the other anthropometric indices and insulin resistance was also observed in the thylakoid group, compared to the placebo group (p < .001, for all parameters). Thylakoid-rich spinach extract combined with a low-calorie diet increased circulating omentin-1 and decreased fat mass, abdominal obesity, as well as circulating chemerin, neopterin, and insulin in obese women with PCOS.

Alpha-lipoic acid supplementation significantly reduces the risk of obesity in an updated systematic review and dose response meta-analysis of randomised placebo-controlled clinical trials.

BACKGROUND: There are numerous trials reported the effect of alpha-lipoic acid (ALA) on obesity measurements; while no summarised dose-response meta-analysis is available to address the effects of dose and duration of ALA supplementation on obesity measurements. We aimed to summarise the results of studies evaluating the effects of ALA supplementation on obesity measurements in a systematic review and dose-response meta-analysis. METHODS AND MATERIALS: In a systematic search from Scopus, PubMed, Embase, Proquest electronic databases up to January 2020 relevant studies were retrieved. Randomised, placebo-controlled trials investigating the effect of ALA supplementation on obesity measurements including weight, body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR) and fat mass (FM) were included. Two class and dose-response meta-analysis were performed to data analysis. RESULTS: Totally, 18, 21 and 8 studies were included for the meta-analysis of ALA-weight, ALA-BMI, ALA-WC, respectively. In the two-class meta-analysis, ALA treatment significantly reduced weight (WMD: -2.29 kg, 95% CI: -2.98, 1.60, P < .01) and BMI (WMD: -0.49 kg/m2 , 95% CI:-0.83,-0.15, P = .005) but no effect on WC (WMD: -2.57 cm, 95% CI: -8.91, 3.76; P = .426). While the dose-response meta-analysis revealed that the duration of ALA treatment is a significant factor affecting WC reduction (Pnon-linearity  = .047). While no evidence of departure from linearity was observed for other variables; moreover, subgrouping also revealed that gender could be an important factor affecting the ALA impact on WC which was significant among women (WMD: -4.099; CI: -7.837, -0.361; P = .032). CONCLUSION: According to our finding, ALA treatment significantly reduced BMI, weight in a two-class meta-analysis without evidence of departure from linearity in terms of dose or duration. While the association of ALA treatment on WC is dependent to the duration of the study. Although further trials evaluating the other obesity measurements specially central obesity will be helpful to infer a more reliable result.

Oxidative stress-induced cognitive impairment in obesity can be reversed by vitamin D administration in rats.

BACKGROUND: There is evidence that obesity leads to cognitive impairments via several markers of oxidative stress including glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase and malondialdehyde (MDA) in the hippocampus. Increased inflammatory markers in the brain have obesity triggering effects. In the current study we aimed to investigate the effects of vitamin D on cognitive function, nuclear factor (NF)-κB, tumor necrosis factor (TNF)-α concentration and markers of oxidative stress in the hippocampus of high-fat diet-induced obese rats. METHODS AND MATERIALS: Forty male Wistar rats were divided into two groups: control diet (CD) and high-fat diet (HFD) for 16 weeks; then each group subdivided into two groups including: CD, CD + vitamin D, HFD and HFD + vitamin D. Vitamin D was administered at 500 IU/kg dosage for 5 weeks. Four weeks after supplementation, Morris water maze test was performed. NF-κB and TNF-α concentration in the hippocampus were determined using ELISA kits. Moreover, oxidative stress markers in the hippocampus including GPx, SOD, MDA and CAT concentrations were measured by spectrophotometry methods. RESULTS: HFD significantly increased TNF-α (P = 0.04) and NF-κB (P = 0.01) concentrations in the hippocampus compared with CD. Vitamin D treatment led to a significant reduction in hippocampus NF-κB concentrations in HFD + vitamin D group (P = 0.001); however, vitamin D had no effect on TNF-α concentrations. Moreover, HFD significantly induced oxidative stress by reducing GPx, SOD and increasing MDA concentrations in the hippocampus. Vitamin D supplementation in HFD group also significantly increased GPx, SOD and reduced MDA concentrations. CONCLUSION: Vitamin D improved hippocampus oxidative stress and inflammatory markers in HFD-induced obese rats and improved cognitive performance. Further studies are needed to better clarify the underlying mechanisms.

Glucose homeostasis, insulin resistance and inflammatory biomarkers in patients with non-alcoholic fatty liver disease: Beneficial effects of supplementation with microalgae Chlorella vulgaris: A double-blind placebo-controlled randomized clinical trial.

BACKGROUND: Chlorella vulgaris (C. vulgaris) is reported to improve dyslipidemia and hypertension; however, its effect on inflammatory biomarkers and insulin resistance has not been noticed thus far. Non-alcoholic fatty liver disease (NAFLD) as a hepatic symptom of metabolic syndrome is strongly associated with insulin resistance and inflammation. AIM OF THE STUDY: In the current interventional trial, we aimed to study the effects of C. vulgaris supplementation on glucose homeostasis, insulin resistance and inflammatory biomarkers in patients with NAFLD. METHODS: Seventy NAFLD patients confirmed by ultra-sonographic findings were randomly assigned into intervention group (four 300 mg tablets of C. vulgaris) or placebo group (four 300 mg tablets of placebos) for 8 weeks. Anthropometric measurements, liver enzymes, fasting serum glucose (FSG), insulin, high sensitive C-reactive protein (hs-CRP) and tumor necrosis factor-alpha (TNF-α) were assessed and homeostatic model assessment (HOMA) score for insulin resistance was estimated before and after the intervention. RESULTS: Anthropometric measurements decreased significantly in both group (p < 0.001). However, mean reduction in weight was significantly higher in C. vulgaris - treated group compared to placebo group. Serum concentrations of liver enzymes, FSG and hs-CRP also significantly decreased and serum insulin concentration and HOMA score increased significantly only in C. vulgaris-treated group (P < 0.001, P < 0.006 and P < 0.025, respectively). Mean change in serum glucose and TNF-α levels were significant between the groups even after adjusting for the serum insulin and baseline values of variables (P = 0.014, P = 0.005, P = 0.014, respectively); between-group differences were not significant for the other variables by the end of study. CONCLUSION: To our finding, C. vulgaris supplementation could be considered as an adjunctive therapy to decrease weight and improve glycemic status and reducing hs-CRP as well as improving liver function in patients with NAFLD. IRCT NUMBER: 201202233320N7.