Department of Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA.
Nutr Clin Pract. 2012 Apr;27(2):215-25. doi: 10.1177/0884533611434934. Epub 2012 Feb 29.
The human intestinal tract comprises a rich and complex microbial ecosystem. This intestinal microbota provides a large reservoir of potentially toxic molecules, including bacterial endotoxin (ie, lipopolysaccharide [LPS]). This potent inflammatory molecule is detectable in the circulation of healthy individuals, and levels transiently increase following ingestion of energy-rich meals. Chronic exposure to circulating endotoxin has been associated with obesity, diabetes, and cardiovascular disease. Western-style meals augment LPS translocation and by this mechanism may contribute to the pathogenesis of these diseases. By contrast, the gut and other organs have evolved mechanisms to detoxify endotoxin and neutralize the potentially inflammatory qualities of circulating endotoxin. Of specific interest to clinicians is evidence that acute postprandial elevation of circulating endotoxin is dependent on meal composition. In this review, the authors present an overview of the biochemical and cellular mechanisms that lead to endotoxemia, with emphasis on the interplay between microbial and nutrition determinants of this condition. The link between endotoxemia, diet, and changes in the intestinal microbiota raise the possibility that dietary interventions can, at least in part, ameliorate the detrimental outcomes of endotoxemia.
人类肠道包含一个丰富而复杂的微生物生态系统。这个肠道微生物群为潜在有毒分子提供了一个巨大的储存库，包括细菌内毒素（即脂多糖[LPS]）。这种有效的炎症分子在健康个体的循环中可检测到，并且在摄入高热量膳食后会短暂增加。循环内毒素的慢性暴露与肥胖、糖尿病和心血管疾病有关。西式膳食会增加 LPS 的易位，通过这种机制可能会导致这些疾病的发病机制。相比之下，肠道和其他器官已经进化出了解毒内毒素和中和循环内毒素潜在炎症特性的机制。令临床医生特别感兴趣的是有证据表明，餐后循环内毒素的急性升高取决于膳食组成。在这篇综述中，作者介绍了导致内毒素血症的生化和细胞机制概述，重点介绍了这种情况中微生物和营养决定因素之间的相互作用。内毒素血症、饮食和肠道微生物群变化之间的联系提出了这样一种可能性，即饮食干预至少可以部分改善内毒素血症的不良后果。
