ABSTRACT
Chronic low-grade inflammation is a common feature of obesity and plays a crucial role in the progression of its complications. Vitamin D (VitD) plays an important role in modulating the immune response and regulating inflammation. Thus, this systematic review and meta-analysis aimed to evaluate the effects of isolated VitD supplementation on main inflammatory markers in overweight and obese individuals with no comorbidities and with VitD deficiency. We hypothesized that the increase in serum VitD concentrations after supplementation would significantly reduce the concentrations of inflammatory markers. The search was conducted in Medline/PubMed, SCOPUS, EMBASE, and Web of Science. Eleven randomized placebo-controlled studies were included in the final analysis, with a total of 504 participants and daily (1000-7000 international units) or bolus (100,000-200,000 international units) doses of VitD lasting from 2 to 26 weeks. The VitD supplementation did not influence C-reactive protein (mean difference [MD]: 0.01; 95% confidence interval [CI] -0.37, 0.39; P = .97), interleukin-6 (MD: -0.34; 95% CI -1.09, 0.42; P = .38), and tumor necrosis factor concentrations (MD: -0.02; 95% CI -0.23, 0.19; P = .85). In the analysis considering the studies with a significant increase in serum VitD concentrations, VitD supplementation also did not influence C-reactive protein (MD: -0.17; 95% CI -0.88, 0.54; P = .64), interleukin-6 (MD: -0.47; 95% CI -1.31, 0.37; P = .27), and tumor necrosis factor concentrations (MD: 0.01; 95% CI -1.34, 1.37; P = .98). This meta-analysis suggests that VitD supplementation does not significantly alter inflammatory markers in overweight and obese individuals.
ABSTRACT
CONTEXT: Riboflavin (vitamin B2) is a water-soluble micronutrient considered to be a precursor of the nucleotides flavin adenine dinucleotide and flavin mononucleotide. This vitamin makes up mitochondrial complexes and participates as an enzymatic cofactor in several mechanisms associated with energy metabolism. OBJECTIVE: This systematic review collected and discussed the most relevant results on the role of riboflavin in the energy metabolism of lipids, proteins, and carbohydrates. DATA SOURCES: A systematic search was carried out in the PubMed-Medline, Scopus, Embase, and Web of Science databases using the PICOS (Population, Intervention, Comparison, Outcome, Study design) strategy. DATA EXTRACTION: The screening of studies went through 2 stages following predefined eligibility criteria. The information extracted covered reference details, study design, population characteristics, experimental model, treatment parameters and dosage, route of administration, duration of treatment, and results found. DATA ANALYSIS: The risk of bias was assessed using the SYRCLE Risk of Bias (RoB) tool for in vivo studies and the QUIN tool adapted for in vitro studies, utilizing 10 domains, including selection bias, performance bias, detection bias, attrition bias, reporting bias, and other biases, to evaluate the methodological quality of the included studies. CONCLUSION: This review concludes that riboflavin regulates energy metabolism by activating primary metabolic pathways and is involved in energy balance homeostasis.
ABSTRACT
Polyphenol supplementation during early life has been associated with a reduction of oxidative stress and neuroinflammation in diseases caused by oxygen deprivation, including cerebral palsy, hydrocephaly, blindness, and deafness. Evidence has shown that perinatal polyphenols supplementation may alleviate brain injury in embryonic, fetal, neonatal, and offspring subjects, highlighting its role in modulating adaptative responses involving phenotypical plasticity. Therefore, it is reasonable to infer that the administration of polyphenols during the early life period may be considered a potential intervention to modulate the inflammatory and oxidative stress that cause impairments in locomotion, cognitive, and behavioral functions throughout life. The beneficial effects of polyphenols are linked with several mechanisms, including epigenetic alterations, involving the AMP-activated protein kinase (AMPK), nuclear factor kappa B (NF-κB), and phosphoinositide 3-kinase (PI3K) pathways. To highlight these new perspectives, the objective of this systematic review was to summarize the understanding emerging from preclinical studies about polyphenol supplementation, its capacity to minimize brain injury caused by hypoxia-ischemia in terms of morphological, inflammatory, and oxidative parameters and its repercussions for motor and behavioral functions.
