西方饮食、菌群及认知损伤之间互相关联的机制
Title：
Gut to Brain Dysbiosis: Mechanisms Linking Western Diet Consumption, the Microbiome, and Cognitive Impairment
Abstract：
Consumption of a Western Diet (WD) that is high in saturated fat and added sugars negatively impacts cognitive function, particularly mnemonic processes that rely on the integrity of the hippocampus. Emerging evidence suggests that the gut microbiome influences cognitive function via the gut-brain axis, and that WD factors significantly alter the proportions of commensal bacteria in the gastrointestinal tract. Here we review mechanisms through which consuming a WD negatively impacts neurocognitive function, with a particular focus on recent evidence linking the gut microbiome with dietary- and metabolic-associated hippocampal impairment. We highlight evidence linking gut bacteria to altered intestinal permeability and blood brain barrier integrity, thus making the brain more vulnerable to the influx of deleterious substances from the circulation. WD consumption also increases production of endotoxin by commensal bacteria, which may promote neuroinflammation and cognitive dysfunction. Recent findings also show that diet-induced alterations in gut microbiota impair peripheral insulin sensitivity, which is associated with hippocampal neuronal derrangements and associated mnemonic deficits. In some cases treatment with specific probiotics or prebiotics can prevent or reverse some of the deleterious impact of WD consumption on neuropsychological outcomes, indicating that targeting the microbiome may be a successful strategy for combating dietary- and metabolic-associated cognitive impairment.
All Authors：
Emily E Noble,Ted M Hsu,Scott E Kanoski
First Authors：
Emily E Noble
Correspondence：
Scott E Kanoski
内容要点：
含有高饱和脂肪及大量添加糖的西方饮食对认知功能，尤其是依赖海马体完整性的记忆过程有着负面影响.肠道菌群通过肠-脑轴影响认知功能，西方饮食显著改变了胃肠道内的共生细菌组成。本综述介绍了西方饮食对神经认知功能造成负面影响的机制，特别关注了肠道菌群与饮食及代谢相关海马体损伤之间的关联的研究。肠道菌群改变了肠道通透性及血脑屏障完整性，导致脑更易受到循环系统中有害物质的攻击。