Abstract：
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.
摘要：
越来越多的证据证明自闭症儿童有胃肠道问题。然而,孤独症和非孤独症儿童的肠道菌群(GM)存在显著差异.转基因的这些变化可能源于几个因素。最近,研究人员专注于营养因素，尤其是维生素缺乏。因此，我们的系统综述调查了自闭症之间的联系，GM变更，和维生素A缺乏症（VAD），通过分析2010年至2022年来自PubMed和Embase数据库的研究。坚持PRISMA准则，我们精心挑选了19项相关研究,这些研究确立了自闭症与转基因改变之间或自闭症与VAD之间的联系.我们的发现一致地指出自闭症患者的转基因发生了显着变化，表明这些变化是该疾病的有希望的生物标志物。尽管转基因改变与自闭症有一致的关联，我们的分析显示,自闭症患者和VAD患者的GM成分没有显著差异.这表明VAD,尤其是在生命早期遇到的时候，可能在自闭症的发病中起作用。此外，我们的评论强调了自闭症儿童视黄酸水平降低之间的明显相关性，这可能与自闭症症状的严重程度有关。我们的研究结果是双重的：它们不仅加强了转基因改变作为潜在诊断标志物的重要性，而且突出了进一步研究营养干预措施的迫切需要。具体来说,补充维生素A成为缓解自闭症症状的一个有希望的途径，保证对其治疗潜力进行更深入的调查。
