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.

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 effect of almond intake on cardiometabolic risk factors, inflammatory markers, and liver enzymes: A systematic review and meta-analysis.

Almond intake may be correlated with improvements in several cardiometabolic parameters, but its effects are controversial in the published literature, and it needs to be comprehensively summarized. We conducted a systematic search in several international electronic databases, including MEDLINE, EMBASE, Scopus, Web of Science, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov until April 2021 to identify randomized controlled trials that examined the effects of almond consumption on cardiometabolic risk factors, inflammatory markers, and liver enzymes. Data were pooled using the random-effects model method and presented as standardized mean differences (SMDs) with 95% confidence intervals (CIs). Twenty-six eligible trials were analyzed (n = 1750 participants). Almond intake significantly decreased diastolic blood pressure, total cholesterol, triglyceride, low-density lipoprotein (LDL), non-high-density lipoprotein (HDL), and very LDL (p < 0.05). The effects of almond intake on systolic blood pressure, fasting blood glucose, insulin, hemoglobin A1c, homeostatic model assessment of insulin resistance, C-peptide, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, C-reactive protein (CRP), hs-CRP (high sensitivity C-reactive protein), interleukin 6, tumor necrosis factor-α, ICAM (Intercellular Adhesion Molecule), VCAM (Vascular Cell Adhesion Molecule), homocysteine, HDL, ox-LDL, ApoA1, ApoB, and lipoprotien-a were not statistically significant (p > .05). The current body of evidence supports the ingestion of almonds for their beneficial lipid-lowering and antihypertensive effects. However, the effects of almonds on antiinflammatory markers, glycemic control, and hepatic enzymes should be further evaluated via performing more extensive randomized trials.

The effect of needle type (25 G Sprotte vs. Quincke) in spinal anesthesia on the incidence of transient neurologic syndrome: A randomized clinical trial.

Background and Aims: Transient neurologic syndrome (TNS) is a postoperative pain in the back and buttock that can occur after spinal anesthesia. The spinal needle design may have an impact on the occurrence of TNS. We decided to compare the incidence of TNS and related factors between two spinal needle types. Methods: In this randomized clinical trial, 150 patients aged 18-60 years and American Society of Anesthesiologists (ASA) physical status I who underwent lower abdomen or lower extremity surgeries with spinal anesthesia and supine position were enrolled. They were randomly divided into two groups (25 G Quincke or Sprotte needle) with 0.5% bupivacaine (12.5 mg). After the operation, the patients were asked to report any pain in the lower back, buttock, and thigh areas. A Visual Analog Scale (VAS) was also used to record the severity of the pain. Results: Overall, 45 patients developed TNS. Twenty-nine patients in the Sprotte group (38.7%) and 16 patients in the Quincke group (21.3%) developed TNS (p = 0.75). More patients in the Sprotte group (25.3%) had severe pain (VAS score of 8-10) when compared with the Quincke group (6.7%). There was no significant difference in TNS symptoms duration between the two groups. In about half of patients (51.9%) in the Sprotte group and 57.3% of patients in the Quincke group, the symptoms resolved after 2-3 h. Conclusion: Although the incidence of TNS did not differ significantly, patients for whom a Sprotte spinal needle had been used had more severe pain. This suggests that the Quincke needle caused less severe pain.

Effect of melatonin supplementation on cardiometabolic risk factors, oxidative stress and hormonal profile in PCOS patients: a systematic review and meta-analysis of randomized clinical trials.

BACKGROUND: To investigate whether melatonin supplementation can enhance cardiometabolic risk factors, reduce oxidative stress, and improve hormonal and pregnancy-related factors in patients with PCOS. METHODS: We conducted a systematic search of PubMed/Medline, Scopus, and the Cochrane Library for articles published in English from inception to March 2023. We included randomized controlled trials (RCTs) on the use of melatonin for patients with polycystic ovary syndrome (PCOS). We performed a meta-analysis using a random-effects model and calculated the standardized mean differences (SMDs) and 95% confidence intervals (CIs). RESULTS: Six studies met the inclusion criteria. The result of meta-analysis indicated that melatonin intake significantly increase TAC levels (SMD: 0.87, 95% CI: 0.46, 1.28, I2 = 00.00%) and has no effect on FBS, insulin, HOMA-IR, TC, TG, HDL, LDL, MDA, hs-CRP, mFG, SHBG, total testosterone, and pregnancy rate in patients with PCOS compare to controls. The included trials did not report any adverse events. CONCLUSION: Melatonin is a potential antioxidant that may prevent damage from oxidative stress in patients with PCOS. However, the clear effect of melatonin supplementation on cardiometabolic risk factors, hormonal outcomes, and pregnancy-related outcomes needs to be evaluated further in large populations and long-term RCTs.

Does vitamin D supplementation impact serotonin levels? A systematic review and meta-analysis.

Background and Aims: Vitamin D deficiency impacts a significant proportion of the world's population, and this deficiency has been linked to various conditions characterized by imbalanced serotonin regulation. The objective of this systematic review and meta-analysis was to evaluate the effect of vitamin D supplementation on serum serotonin levels. Methods: We conducted a comprehensive search of PubMed, Scopus, Cochrane Central for Randomized Clinical Trials, and Web of Science up to September 2022, without any language restrictions. The effect sizes were calculated using the standard mean difference (SMD) and 95% confidence interval (CI). Results: Six randomized clinical trials involving 356 participants were included in the analysis. Our findings indicated no significant changes in serotonin levels between the intervention and control groups (SMD: 0.24 ng/mL, 95% CI: -0.28, 0.75, p > 0.10). Subgroup analysis also did not reveal any significant changes in serotonin levels among children, participants with autism spectrum disorders, interventions lasting 10 weeks or longer, or those receiving vitamin D doses below 4000 IU/day. Conclusion: Although the results obtained in this systematic review are inconclusive, they support the need for further well-designed randomized trials to assess the potential role of vitamin D supplementation in regulating serotonin levels and potentially ameliorating depression and related disorders.

The effect of quercetin supplementation on clinical outcomes in COVID-19 patients: A systematic review and meta-analysis.

Coronavirus disease (COVID-19) affects both the respiratory system and the body as a whole. Natural molecules, such as flavonoid quercetin, as potential treatment methods to help patients combat COVID-19. The aim of this systematic review and meta-analysis is to give a comprehensive overview of the impact of quercetin supplementation on inflammatory factors, hospital admission, and mortality of patients with COVID-19. The search has been conducted on PubMed, Scopus, Web of Science, EMBASE, and the Cochrane Library using relevant keywords until August 25, 2023. We included randomized controlled trials (RCTs) comparing COVID-19 patients who received quercetin supplementation versus controls. We included five studies summarizing the evidence in 544 patients. Meta-analysis showed that quercetin administration significantly reduced LDH activity (standard mean difference (SMD): -0.42, 95% CI: -0.82, -0.02, I 2 = 48.86%), decreased the risk of hospital admission by 70% (RR: 0.30, 95% CI: 0.14, 0.62, I 2 = 00.00%), ICU admission by 73% (RR: 0.27, 95% CI: 0.09, 0.78, I 2 = 20.66%), and mortality by 82% (RR: 0.18, 95% CI: 0.03, 0.98, I 2 = 00.00%). No significant changes in CRP, D-dimmer, and ferritin were found between groups. Quercetin was found to significantly reduce LDH levels and decrease the risk of hospital and ICU admission and mortality in patients with COVID-19 infection.

Muscle Strength and Biochemical Markers as Predictors of Depression in Hemodialysis Patients: A Cross-Sectional Study.

Patients with chronic renal failure, many of which treated with hemodialysis, present a high prevalence of impaired muscle strength which suggest that muscle mass parameters may be used as markers for changes in muscle in these patients. Measurement of handgrip strength (HGS) is a common, simple, and quick measure of muscle function an indicator of overall muscle strength which has been associated with physical activity and several anthropometric traits. Intercellular adhesion molecule-1 (ICAM-1) and insulin-like growth factor-1 (IGF-1) are biochemical markers associated with inflammatory processes which are a common consequence of dialysis. Additionally, hemodialysis patients frequently present signs of malnutrition and depression. This cross-sectional study aimed to evaluate if muscle and biochemical markers could be used to predict the risk of depression in hemodialysis patients. Several anthropometric parameters, nutrient intake, depression state and the serum levels of ICAM-1 and IGF-1 were determined and Pearson's correlation coefficient and/or Spearman's correlation coefficient were used to test the correlation between them. Our results do not show a correlation between HGF, IGF-1 and ICAM-1 with the depression status of the patients, but mid-arm muscle circumference (MAMC) was statistically and positively correlated with depression. Additionally, ICAM-1 levels were negatively correlated with HGS, MAMC, and IGF-1. Overall, the results of the present study suggest that HGS may be used as an indicator of cardiovascular diseases and MAMC may be a good predictor of the level of depression in hemodialysis patients, although further studies are required.

Effect of synbiotic bread containing lactic acid on blood lipids and apolipoproteins in patients with type 2 diabetes: A randomized controlled trial.

Recently, the use of synbiotics for managing various diseases has dramatically increased. Synbiotics have been shown to be a good approach to influence the composition of the gut microbiota with positive health effects. Management of type 2 diabetes mellitus (T2DM) complications is one of the reasons for the ingestion of synbiotics and so the aim of the current study was to determine the effects of synbiotic bread intake on markers of lipid profile in T2DM patients. One hundred T2DM patients (age between 20 and 60 years) were randomly assigned to four groups to consume different types of synbiotic bread, three times/day, for 8 weeks: "synbiotic + lactic acid" (n = 25; IV), "synbiotic" (n = 25; III), "lactic acid brad" (n = 25; II), or "control" (n = 25; I). The measured outcomes included anthropometric characteristics, glycemic control parameters, blood lipids, and apolipoproteins. The consumption of "synbiotic + lactic acid bread" (group IV) and "lactic acid bread" (group II) led to a significant decrease in total cholesterol (TC) and glycated hemoglobin (HbA1c) compared to the "control bread." The HbA1c levels were also significantly lower when compared to group II. Additionally, apolipoprotein A (Apo A1) levels were significantly decreased in group IV, compared to control and other groups (post hoc analysis). No significant differences between groups were observed for triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and apolipoprotein B100 (Apo B100) levels. The observed results show that the synbiotic bread (with or without lactic acid) promoted a decrease in total cholesterol (TC) and Apo A1 in diabetic patients when consumed daily for 8 weeks.