Effects of hydrolyzed collagen alone or in combination with fish oil on the gut microbiome in patients with major burns.

Burns are associated with gut dysbiosis. Collagen peptides and omega-3 fatty acids (FAs) are suggested to improve wound healing and the inflammatory response. These are also correlated with microbiome colonization. Therefore, the present study aimed to investigate the effect of hydrolyzed collagen alone or in combination with fish oil on specific species of the gut microbiome in patients with major burns. In this randomized double-blind clinical trial, 57 adults (aged 18-60 years) with 20-45% total body surface area burns were randomised into three groups to receive either 40 gr hydrolyzed collagen +10 ml sunflower oil, 40 g hydrolyzed collagen +10 ml fish oil or placebo, divided into two daily drinks, for two weeks. Gut bacteria were measured using the real-time quantitative polymerase chain reaction (qPCR) method. The mean concentration of Bifidobacterium was significantly reduced in the control (P = 0.002) and collagen (P = 0.005) groups compared with the baseline values, whereas no significant change was observed in the collagen omega-3 group. The Firmicutes to Bacteroidetes ratio decreased significantly in the collagen group (p = 0.002) after supplementation compared to baseline . No significant changes in concentration of Lactobacillus, Enterobacteriaceae, and F.prausnitzii were observed between or within the study groups. Two weeks of supplementation with collagen and omega-3 FAs in patients with major burns did not result in a significant difference in the concentration of bacteria measured between the study groups. However, the addition of omega-3 FAs prevented a significant reduction in gut Bifidobacterium. Future studies are suggested to investigate the potential efficacy of these nutrients in improving the gut microbiota and clinical outcomes in major burns. REGISTRATION NUMBER: IRCT20131125015536N9.

Effect of Collagen Hydrolysate and Fish Oil on High-Sensitivity C-Reactive Protein and Glucose Homeostasis in Patients with severe Burn; a Randomized Clinical Trial.

INTRODUCTION: Collagen and omega-3 fatty acids (FAs) are suggested to have anti-inflammatory, anti-oxidant, and insulin-sensitizing properties. The aim of this study was to investigate the effect of collagen hydrolysate and omega-3 FAs on inflammation and insulin resistance in patients with major burns. METHODS: In this double-blind randomized clinical trial, 66 patients with 20-45% burns were assigned to either of the three groups of collagen (40 gr/d), collagen (40 gr/d) plus fish oil (10 ml/d), or control. High-sensitivity C-reactive protein (hs-CRP), fasting blood glucose (FBG) and insulin concentrations, and homeostatic model assessment for insulin resistance (HOMA-IR) were assessed at baseline, as well as end of weeks two and three. RESULTS: Based on post-hoc analyses, hs-CRP levels were significantly lower in the collagen (p=0.026) and collagen+omega-3 (p=0.044) groups compared to the control group, at week three. However, pre- to post- (week three) changes of hs-CRP were significantly higher only in the collagen+omega-3 group compared to the control group (173.2 vs. 103.7 mg/l, p=0.024). After three weeks of the intervention, insulin (11.3 and 11.9 vs. 22.8 µIU/ml) and HOMA-IR (2.9 and 2.8 vs. 7.9) values seemed to be clinically, but not statistically, lower in both intervention groups compared to the control group. Pre- to post- (week three) values of FBG decreased significantly in the collagen (p=0.002) and collagen+omega-3 (p=0.036) groups. Insulin (p=0.008) and HOMA-IR (p=0.001) decreased significantly only in the collagen+omega-3 group at week three compared to the baseline. CONCLUSIONS: Supplementation with collagen hydrolysate and omega-3 FAs can improve hs-CRP concentration and probably insulin resistance in patients with severe burns. Omega-3 FAs had additional effects on modulating inflammation. Larger clinical trials are needed to confirm the current findings especially in terms of glucose homeostasis.

Effect of bariatric surgery on endogenous sex hormones and sex hormone-binding globulin levels: a systematic review and meta-analysis.

BACKGROUND: Most studies have shown beneficial effect of bariatric surgery (BS) on serum levels of sex hormones. OBJECTIVE: A systematic review and meta-analysis was conducted to examine the magnitude of possible changes in levels of sex hormones following BS. SETTINGS: Electronic databases were searched, including PubMed, Scopus, Web of Science, and Embase, for relevant studies. METHODS: The heterogeneity of the studies was examined by χ2 tests and the degree of heterogeneity was estimated using I2 statistic. RESULTS: The results of pooled analyses revealed that BS caused a significant increase in luteinizing hormone (LH), follicular stimulating hormone (FSH), total testosterone (TT), and sex hormone binding globulin (SHBG) levels and conversely, decreased dehydroepiandrosterone (DHEA) and estradiol (E2) levels in males. For females, BS significantly increased LH, FSH, and SHBG levels and conversely, decreased androstenedione (AE), E2 and TT levels. Additionally, the level of progesterone (P), prolactin (PRL), free testosterone (FT) and dehydroepiandrosterone sulfate (DHEA-S) showed no significant changes in patients who had undergone BS. CONCLUSION: BS changed most sex hormones levels including LH, FSH, TT, SHBG, AE, DHEA, and E2. It seems that BS is able to exert substantial impacts on sex hormones levels and as well as sexual function, however, larger, and more precise trials are required to specifically focus on these claims.

Effect of evening primrose oil supplementation on lipid profile: A systematic review and meta-analysis of randomized clinical trials.

BACKGROUND: Studies have shown that evening primrose oil (EPO) supplementation might be effective in improving lipid profile, however, the results are inconsistent. This study was performed to determine the direction and magnitude of the EPO effect on the lipid profile. METHODS: PubMed, Scopus, Cochrane Library, Embase and Web of Science databases and Google Scholar were searched up to September-2019. Meta-analysis was performed using the random-effects model. Lipid profile including high-density lipoprotein (HDL), total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL) was considered as the primary outcome. RESULTS: A total of 926 articles were identified through database searching, of which, six RCTs were included in the meta-analysis. There were six studies on HDL, TC, and TG and four studies on LDL. EPO supplementation had no significant effect on TC, TG, LDL, and HDL. However, in subgroup analysis, a significant reduction in TG at a dose of ≤4 g/day (weighted mean difference [WMD] = -37.28 mg/dl; 95% CI: -73.53 to -1.03, p = .044) and a significant increase in HDL in hyperlipidemic subjects (WMD = 5.468 mg/dl; 95% CI: 1.323 to 9.614, p = .010) was found. CONCLUSION: Oral intake of EPO at a dose of ≤4 g/day significantly reduces serum TG levels and significantly increases HDL levels in hyperlipidemic subjects.

Vitamin D suppresses proangiogenic factors in patients with ulcerative colitis: A randomized double blind placebo controlled clinical trial.

BACKGROUND: Angiogenesis and inflammation are involved in the pathogenesis of ulcerative colitis (UC). This study aimed to assess the effect of vitamin D on serum levels of proangiogenic factors, visfatin and vascular endothelial growth factor (VEGF), in patients with UC. MATERIALS AND METHODS: Ninety patients were randomized to receive either a single intramuscular injection of 300,000 IU vitamin D or normal saline. Visfatin, VEGF, and 25-hydroxyvitamin D [25(OH)D] concentrations were assessed before and 90 days after the intervention. RESULTS: There were no significant differences in visfatin and VEGF levels between the two groups following supplementation. In patients with vitamin D insufficiency, visfatin increase was significantly lower in the intervention versus placebo group. There was an inverse correlation between serum 25(OH)D and visfatin in the subgroup with vitamin D insufficiency. CONCLUSION: Vitamin D might be beneficial in decreasing proangiogenic factors such as visfatin in UC patients with low 25(OH)D levels.