A systematic review and meta-analysis of the omega-3 fatty acids effects on brain-derived neurotrophic factor (BDNF).

BACKGROUND: Omega-3 fatty acids (omega-3 FAs) have attracted the attention of researchers because of their influence on circulatory levels of brain-derived neurotrophic factor (BDNF). Our objective was to review systematically and Meta-analyze randomized controlled trials (RCTs) to assess the effects of omega-3 FAs supplementation on serum BDNF concentration. METHODS: Scopus, PubMed, Web of Science, and Cochrane Library were systematically searched until April 2023. The Cochrane risk of bias assessment tool was utilized to evaluate the quality of the studies. A random-effects model was employed to estimate the overall effect size of BDNF levels, using the Standard Mean Difference (SMD) and a 95% confidence interval (CI). The heterogeneity among the studies was assessed using chi-squared and I2 statistics. RESULTS: A total of 12 studies involving 587 subjects were included. The supplementation of PUFA was found to be associated with a significant increase in serum levels of BNDF in the group receiving the supplements, as compared to the placebo group (SMD: 0.72 pg/mL, 95% CI: 0.28, 1.15; P < 0.001) (I2 = 84.39%, P < 0.001). Sub-group analyses revealed similar findings in trials with fewer than 10 weeks, which utilized both animal (fish oil) and herbal (flaxseed) forms of omega-3 supplements with a high daily dosage of 2000mg. CONCLUSION: The present systematic review and meta-analysis indicate the efficacy of omega-3 FAs in increasing the serum concentration of BDNF. Therefore, omega-3 FAs should be prioritized as agents for increasing BDNF in interventions.

Effect of sumac powder on clinical symptoms, hyperandrogenism, inflammation, blood glucose, lipid profiles in women with polycystic ovary syndrome: A double-blind randomized clinical trial.

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders associated with a high risk of diabetes, atherosclerosis, and cardiovascular disease. The purpose of this study was to determine the effect of sumac powder on clinical symptoms and laboratory parameters in women with PCOS. The double-blind randomized controlled clinical trial was conducted on 88 women with PCOS randomly assigned to the intervention and control groups. The intervention group received three capsules each containing 1 g of sumac powder for 12 weeks. All data and serum levels of sex hormone, hs-CRP, glucose, and lipid profiles were measured at the baseline and at the end of the study. Data were analyzed using SPSS version 25 software. The ANCOVA test results showed that hs-CRP level was significantly reduced in the intervention group (p = .008). Blood glucose and lipid profiles in the intervention group were significantly reduced compared to the placebo group (p < .05). Insulin sensitivity and HDL levels were increased significantly in the Sumac group after the intervention (p < .05). Sumac powder can reduce the inflammatory effects, and glycemic status and lipid profile of polycystic ovaries in affected women, but has no significant effect on anthropometric parameters and sex hormones.

The effect of Conjugated Linoleic Acid intake on oxidative stress parameters and antioxidant enzymes: A systematic review and meta-analysis of randomized clinical trials.

Conjugated Linoleic Acid (CLA) are thought to pose beneficial effects on inflammatory responses and oxidative stress (OS). Thus, the present systematic review and meta-analysis of randomized controlled trials (RCTs) aimed to assess the net effects of CLA supplementation on various OS parameters and antioxidant enzymes. PubMed/MEDLINE, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials databases were searched for publications on CLA supplementation effects on OS parameters up to March 2021. The data extracted from eligible studies were expressed as standardized mean difference with 95% confidence intervals and then combined into meta-analysis using the random-effects model. Overall, 11 RCTs (enrolling 586 participants) met the inclusion criteria and were included in meta-analysis; however, since those trials evaluated different OS parameters, meta-analysis was carried out considering different sets for each parameter separately. According to our results, CLA supplementation significantly increases 8-iso-PGF2α urinary concentration (SMD: 2; 95% CI: 0.74, 3.27; I2 = 87.7%). On contrary, the intervention does not seem to change 15-keto-dihydro-PGF2α urinary concentration, nor the serum levels of CAT, SOD, GPx and MDA. Taken all together, CLA supplementation does not appear to have substantial effects on OS markers in general; albeit due to relatively small sample size and high level of heterogeneity between studies, the obtained findings should be interpreted with caution. Further large well-designed RCTs, investigating the impact of CLA and including various groups of patients, are still needed.

The effects of extra virgin olive oil and canola oil on inflammatory markers and gastrointestinal symptoms in patients with ulcerative colitis.

BACKGROUND/OBJECTIVES: Ulcerative colitis (UC) is an immune-mediated disease that causes inflammation in the gastrointestinal tract. Diet has an important role in the treatment of UC. This study aimed to compare the effects of extra virgin olive oil (EVOO), as a functional food, with canola oil in the treatment of UC. SUBJECTS/METHODS: Forty patients were participating in this crossover clinical trial. Thirty two patients completed two intervention rounds. Blood samples were taken before and after 20 days intervention. Disease activity score and gastrointestinal symptoms were evaluated using the Mayo score and gastrointestinal symptom rating scale (GSRS) respectively. RESULTS: Erythrocyte sedimentation rate (p = 0.03) and high-sensitivity C-reactive protein (p < 0.001) were decreased significantly after EVOO consumption. Bloating, constipation, fecal urgency, incomplete defecation, and final GSRS were reduced significantly after EVOO consumption (p < 0.05). CONCLUSIONS: Intake of EVOO decreased the inflammatory markers and improved gastrointestinal symptoms in UC patients. It seems this functional food can be beneficial in the treatment of UC as a complementary medicine.