Gut microbiota, vitamin A deficiency and autism spectrum disorder: an interconnected trio - a systematic review.

Accumulating evidence proves that children with autism have gastrointestinal problems. However, a significant difference in gut microbiota (GM) exists between autistic and non-autistic children. These changes in the GM may stem from several factors. Recently, researchers focused on nutritional factors, especially vitamin deficiency. Thus, our systematic review investigates the connections among autism, GM alterations, and vitamin A deficiency (VAD), by analyzing studies sourced from PubMed and Embase databases spanning from 2010 to 2022. Adhering to PRISMA guidelines, we meticulously selected 19 pertinent studies that established links between autism and GM changes or between autism and VAD. Our findings uniformly point to significant alterations in the GM of individuals with autism, indicating these changes as promising biomarkers for the disorder. Despite the consistent association of GM alterations with autism, our analysis revealed no notable differences in GM composition between individuals with autism and those experiencing VAD. This suggests that VAD, especially when encountered early in life, might play a role in the onset of autism. Furthermore, our review underscores a distinct correlation between reduced levels of retinoic acid in children with autism, a disparity that could relate to the severity of autism symptoms. The implications of our findings are twofold: they not only reinforce the significance of GM alterations as potential diagnostic markers but also spotlight the critical need for further research into nutritional interventions. Specifically, vitamin A supplementation emerges as a promising avenue for alleviating autism symptoms, warranting deeper investigation into its therapeutic potential.

Sub-acute toxicity of graphene oxide (GO) nanoparticles in male mice after intraperitoneal injection: Behavioral study and histopathological evaluation.

Graphene oxide (GO) is a graphene derivative used for numerous applications in which biomedical uses are significant. However, for this application, the security of GO is doubtful. In this work, we synthesized this nanoparticle to assess its toxicity in male mice. In addition, we studied the effects of this nanomaterial on behavior by administering GO intraperitoneally to mice at different doses (2 mg/kg and 5 mg/kg) for five days. Subsequently, we performed biochemical analyses of blood serum and measured peroxidase and malondialdehyde (MDA) activity. Then, we performed histological sections to evaluate the brain's and liver's pathological and morphological changes. The data showed that the open field tests did not alter the locomotor activity. Furthermore, the elevated cross-maze tests showed no anxiety effect in the GO doses in the animals. The biochemical analyses indicated that GO influenced the level of biochemical parameters. Although, the oxidative stress assay showed an increase in peroxidase and MDA activity after GO intoxication. However, histopathological analysis of liver sections showed that GO caused liver inflammation, whereas, at the brain level, GO did not affect neuronal cells. The results indicate that GO caused toxic effects and that its toxicity could be mediated by oxidative stress.