老年人肠道菌群特征与代谢和免疫机能相关性的探究

EXPLORATION ON THE CHARACTERISTICS OF INTESTINAL MICROBIOTA IN ASSOCIATION WITH METABOLISM AND IMMUNITY IN THE ELDERLYS

目的研究老年人肠道菌群的特征,探索肠道菌群与机体的生理生化、免疫机能的相关性。方法对成都地区170名中老年人进行生理、生化及免疫指标的检测的同时、采用荧光原位杂交方法(fluorescence in situ hybridization,FISH)对其粪便中的细菌总数、乳酸杆菌(Lactobacillus sp.)、拟杆菌(Bacteroides sp.)、梭菌属(Clostridium sp.)进行定量分析检测。结果 55~65岁乳酸杆菌浓度显著高于55岁及以下组(P<0.05),拟杆菌和梭菌属浓度出现与乳酸杆菌相似的年龄趋势(P<0.05);关联性分析显示年龄与总菌数(r=0.054,P>0.05)、乳酸杆菌数量(r=0.150,P>0.05)、拟杆菌数量(r=0.190,P<0.05)、梭菌属数目(r=0.180,P<0.05)均呈正相关关系;乳酸杆菌与空腹血糖的相关系数为0.241(P<0.01);拟杆菌/梭菌比例与HDL-C显著正相关(r=0.200,P<0.05);总菌数与Ig G正相关(r=0.177,P<0.05)。结论肠道乳酸杆菌、拟杆菌、梭菌数量显著地增多可能是人体肠内细菌老化的重要的特征之一;肠道乳酸杆菌数也许可作为早期发现糖尿病高危人群的新指标;以提高肠道乳酸杆菌为目的中老年人群的益生菌的开发方向需要进一步研究。

Objective To characterize the intestinal microbiota of the healthy elderly,and investigate possible associations among the intestinal microbiota, metabolism and immunity. Methods Total 170 healthy residents 50-70 years old were recruited for the present study. They were divided into 3 groups（≤55 years, 55-65 years, ≥65years）. Every subject was tested for biochemical indicators and immune indexes, and fecal samples were analyzed for total fecal bacterial count, Lactobacillus, Bacteroides and Clostridium quantification using Fluorescence in situ hybridization（FISH）. Results Fecal Lactobacillus,Bacteroides,and Clostridium were significantly increased in 55-65 years group than ≤55 years group（P〈0.05）. The amounts of Bacteroides and Clostridium were positively correlated with age（P〈0.05）. The correlation coefficient between Lactobacillus and glucose（GLU） was 0.241（P〈0.01）. The ratio of Bacteroides to Clostridium was positively associated with HDL-C. Total fecal bacterial count was significantly associated with Ig G（P〈0.05）. ConclusionThe significant increase of fecal Lactobacillus, Bacteroides, and Clostridium along with aging may be one of the characteristics of the aging intestinal microbiota. The fecal Lactobacillus could be used as a new index in monitoring diabetes in the elderly, and the approach to increase fecal Lactobacillus in the elderly needs further study.