益生乳酸菌与肠道菌群稳态

Probiotic Lactic Acid Bacteria and Gut Microbiota Homeostasis

摘要:

肠道是个复杂的微生态系统，不仅包含宿主细胞和各种营养物质，还包含数以万计的微生物。这些肠道微生物与宿主健康息息相关，对宿主营养、代谢、生理和免疫均有影响，肠道菌群发生紊乱还会引起各种疾病。大量临床试验表明，益生乳酸菌可通过调节宿主肠道菌群稳态治疗或缓解多种疾病。本文作者描述了失衡指数（DI）、微生物平衡指数（MBI）和微生物失衡指数（MDI）这3种量化肠道菌群稳态的计算方法及其应用，阐述了益生乳酸菌对肥胖和健康宿主肠道菌群稳态的影响，指出益生乳酸菌可能通过与肠道中病原菌竞争结合位点或分泌物质抑制病原菌，分泌代谢物为肠道中有益共生菌提供适宜生长繁殖的环境和制造“假想敌”刺激宿主免疫系统应答等方式维持宿主肠道菌群稳态，并讨论了维持宿主肠道菌群稳态的重要性。同时还综述了益生乳酸菌研究现状，指出益生乳酸菌的研究要做到个性化，不仅要考虑研究人群个体差异，还要考虑菌株之间的差异。

Abstract:

The gut is a complex ecosystem of host cells, available nutrients and microbiota. The microbiota have close relationship to the host nutrition, metabolism, physiology and immunity, and their disorder will lead to various diseases. Clinical tests indicate that lactic acid bacteria (LAB) with probiotic function can cure or relieve many diseases. This review described three methods for quantifying homeostasis of gut microbiota and their application and elaborated the effect of LAB with probiotic function on the gut microbiota homeostasis of obese and healthy hosts. This literature also pointed out the possible beneficial mechanisms: 1) competing with the pathogenic bacteria in the intestinal tract to bind the site or secreting substance to inhibit the growth of pathogenic bacteria; 2) secreting metabolites to provide livable environment for growth and reproduction of beneficial symbiotic bacteria in the intestinal tract; 3) creating imaginary enemies to stimulate the host immune response. The significance of balancing the host gut microbiota homeostasis was also discussed. Finally, perspectives for probiotic LAB were summarized, and in the future research of probiotic LAB should be personalized, considering not only the individual difference of test population but also the difference among the strains.