Effects of Supplementation with Probiotics in Experimental Models of Alzheimer's Disease: A Systematic Review of Animal Experiments.

BACKGROUND: Conditions along the brain-gut-microbiota (BGM) axis can significantly contribute to the pathogenesis of Alzheimer's disease (AD). Evidence from animal studies indicates a role of probiotics in regulating mood, cognition, and stress response via the BGM axis. However, the effect of probiotics on AD needs to be better clarified in preclinical and clinical studies. METHODS: We prepared this systematic review according to PRISMA. PubMed, Web of Science, Embase, and Virtual Health Library (VHL) were searched for original articles concerning the effects of probiotics in experimental AD. RESULTS: Results were presented as a narrative synthesis according to the Synthesis Without Metaanalysis (SWiM) Guideline. Seventeen studies met the inclusion criteria. The results showed significant effects in the experimental models of AD treated with probiotics alone or in mixture due to expressive improvements in cognitive tests. CONCLUSION: Furthermore, in most of the included studies, it was possible to observe a reduction in inflammatory processes, an increase in the concentration of peptide hormones, insulin homeostasis in the brain, increased antioxidant enzymes, and a decrease in beta-amyloid deposition and tau hyperphosphorylation. Supplementation of probiotics seems to improve performance in cognitive tests and increase the concentration of substances capable of delaying the neurodegenerative process of AD in experimental models.

Estágios maturacionais: comparação de indicadores de crescimento e capacidade física em adolescentes / Maturational stages: comparison of growth and physical capacity indicators in adolescents

INTRODUCTION: The identification of physical capacity is an important marker related to healthy behavior during childhood and adolescence, in which some factors appear to contribute to motor performance such as maturation and hormonal levels. OBJECTIVE: To compare growth indicators, physical capacity and hormonal markers according to gender and maturational stage in adolescents. METHODS: Eighty-nine adolescents of both genders aged 10-13 years participated in the study. Sexual maturation was evaluated using the Tanner's self-evaluation method. Physical capacity (explosive strength of upper and lower limbs, upper limb velocity and agility) and hormonal markers (testosterone and estradiol) were evaluated through the chemiluminescence method. RESULTS: In the comparison by gender, girls had higher weight (p = 0.023), height (p = 0.018) and fat percentage values (p = 0.001), while boys presented better motor performance for the explosive strength of upper limbs (p = 0.005) and lower limbs (p = 0.011), agility (0.018) and upper limb velocity (p = 0.014). Regarding maturational stage, boys did not present differences in any variable analyzed; (Stage V versus I), height (stage III, IV and V versus I) and upper limb explosive strength (stage III and IV versus I). CONCLUSION: Growth, weight and height, as well as explosive strength of upper limbs were higher in girls at more advanced maturational stages and appear to be gender dependent.

INTRODUÇÃO: A identificação da capacidade física se apresenta como importante marcador relacionado ao comportamento saudável durante a infância e adolescência, no qual alguns fatores aparentam contribuir para o desempenho motor como a maturação e níveis hormonais. OBJETIVO: Comparar indicadores de crescimento, capacidades físicas e marcadores hormonais de acordo com o sexo e estágio maturacional em adolescentes. MÉTODO: Participaram do estudo 89 adolescentes de ambos os sexos de 10 a 13 anos. Foram avaliados a maturação sexual, obtida através do método de autoavaliação de Tanner, capacidades físicas (força explosiva de membros superiores e inferiores, velocidade de membros superiores e agilidade) e marcadores hormonais (testosterona e estradiol) através do método de quimiluminescência. RESULTADOS: Na comparação pelo sexo, as meninas obtiveram maiores valores para o peso (p=0,023), estatura (p=0,018) e percentual de gordura (p=0,001), enquanto que os meninos apresentaram melhor rendimento motor para a força explosiva de membros superiores (p=0,005) e inferiores (p=0,011), agilidade (0,018) e velocidade de membros superiores (p=0,014). Em relação ao estágio maturacional os meninos não apresentaram diferenças em nenhuma variável analisada; enquanto as meninas em estágio maturacional mais avançado apresentaram maiores valores para o peso (estágio V versus I), estatura (estágio III, IV e V versus I) e força explosiva de membros superiores (estágio III e IV versus I). CONCLUSÃO: Os indicadores de crescimento, peso e estatura, bem como a força explosiva de membros superiores foram mais elevados nas meninas em estágios maturacionais mais avançados e parecem ser dependentes do sexo.