本文由HelaineE.Resnick博士编辑

    在最新的一期《糖尿病护理》杂志上综述文章总结了肥胖者自身肠道微生物与肥胖特征间的联系，包括葡萄糖代谢异常。

    在正常条件下，肠细菌和宿主是共生关系。然而，一些啮齿类动物和人类研究表明，肠道菌群的组成在瘦者和肥胖者中存在差异，持续观察表明肠道微生物可能在能量平衡中发挥重要作用。据推测，肥胖者的肠道微生物或可特别有效地从饮食中获取能量，这可能是最终导致肥胖和肥胖相关疾病如糖尿病的根本原因。

    为研究肥胖和消瘦者的肠道微生物如何影响各种生理特性，粪便菌群移植（FMT）已在啮齿类动物和人类展开了研究。最新FMT研究表明，对于存在胰岛素抵抗人群，瘦者FMT后可改善外周胰岛素敏感性和对受试者的肠道菌群多样性。

    这一研究表明的潜在的重要内容是肠道微生物多样性的增加，包括丁酸产生菌增加。丁酸、乙酸和丙酸等短链脂肪酸在能量代谢中起重要作用。在小鼠研究表明，口服丁酸可通过增加增加线粒体功能增加胰岛素敏感性和能量消耗。虽然这些结果可能说明肠道微生物与肥胖者特定情况间的潜在联系，但是特定菌群、短链脂肪酸和代谢功能间的因果关系尚未确定。

    未来的研究需要集中于短链脂肪酸补充或FMT的创新研究，以便利用肠道微生物可以解决肥胖和糖尿病的顽固问题。

    原文：

    “Obese” and “Lean” Bacteria: Growing Interest in the Gut MicrobiomeA review in this issue of Diabetes Care （p. 159） summarizes an increasing body of evidence linking features of the gut microbiome to a number of obesity-related conditions, including abnormalities of glucose metabolism. Under normal conditions, there is a symbiotic relationship between bacteria that inhabit the gut and the humans who host them. However, studies in both rodents and humans have shown that the composition of gut microbiota differs between lean and obese subjects—a persistent observation suggesting that the gut microbiome may play a meaningful role in energy balance. It has been postulated that an “obese microbiome” may be particularly efficient at deriving energy from the diet, and this efficiency may ultimately lead to obesity and obesity-related conditions such as diabetes. Fecal microbiota transplantation （FMT） has been used in both rodents and humans to begin to understand how lean and obese microbiota may influence various physiological characteristics. Recent FMT studies in insulin-resistant humans have shown that FMT from lean donors resulted in improvements in pe**heral insulin sensitivity and increases in the diversity of subjects' intestinal microbiota. A potentially important aspect of this observation was that the increased diversity of the gut microbiome included an increase in butyrate-producing bacteria. This is significant because butyrate and acetate and propionate are short-chain fatty acids （SCFAs） that are known to be important in energy metabolism. Studies in mice have shown that oral butyrate increases insulin sensitivity and energy expenditure by increasing mitochondrial function. Although these observations may offer a potential connection between specific features of the gut microbiome and mechanisms that underpin human obesity, a causal link between specific intestinal bacteria, SCFA, and metabolic function has not been established. Moving this line of investigation forward will require innovative studies that focus on SCFA supplementation or FMT from various donors to understand how manipulation of the gut microbiome may be harnessed to address the stubborn problems of obesity and diabetes. — Helaine E. Resnick, PhD, MPH