早产合并认知障碍大鼠粪便短链脂肪酸水平变化

Altered fecal short chain fatty acids in preterm rats with cognitive impairment

目的:分析早产合并认知障碍大鼠肠道菌群及短链脂肪酸变化特征,探讨肠道菌群代谢产物短链脂肪酸改变与早产认知障碍的关系。方法:选取60只孕16~17 d SD大鼠,均分为2组,腹腔注射脂多糖作为实验组,腹腔注射PBS作为对照组。在大鼠孕21 d时行剖宫术获得早产大鼠(足月为22~23 d)。在早产大鼠出生后30 d行认知能力评估,分为对照组与认知障碍组。采用高通量测序检测粪便肠道菌群结构分布,应用气相色谱技术定量检测粪便短链脂肪酸含量。结果:认知障碍组早产大鼠找到平台的平均时间明显长于对照组(P<0.05)。与对照组相比,认知障碍组大鼠变形菌门富集与拟杆菌目、乳杆菌属相对丰度明显降低(P<0.05),总短链脂肪酸与乙酸明显降低(P均<0.05)。乙酸与拟杆菌目、乳杆菌属呈一定的正相关(r=0.488,0.361,P均<0.05)。结论:早产认知障碍大鼠肠道菌群特征为变形菌门富集与拟杆菌目、乳杆菌属含量下降,其中拟杆菌目、乳杆菌属低丰度所致总短链脂肪酸与乙酸下降可能导致早产合并认知功能障碍。

Objective:To analyze the changes of intestinal microflora and short chain fatty acids in premature rats with cognitive impairment,and to explore the relationship between the changes of intestinal microflora metabolites and cognitive impairment of preterm delivery.Methods:Sixty SD rats were randomly divided into two groups.Lipopolysaccharide was injected intraperitoneally as the experiment group and PBS as the control group.The preterm rats were obtained by Cesarean section on the 21st day of gestation(term:22-23 days).The preterm rats were divided into control group and cognitive impairment group 30 days after birth.High throughput sequencing was used to detect the distribution of intestinal microflora,and gas chromatography was used to quantitatively detect the content of short chain fatty acids in feces.Results:The average time of finding platform in cognitive impairment group was significantly longer than that in normal control group(P<0.05).Compared with the control group,the abundance of Proteus in cognitive impairment group was lower than that in Bacteroides and Lactobacillus(P<0.05).Total short chain fatty acids and acetic acid in cognitive impairment group were significantly decreased(all P<0.05).Acetic acid was positively correlated with Bacteroides and Lactobacillus(r=0.488 and 0.361,both P<0.05).Conclusion:The intestinal microflora of rats with cognitive impairment of preterm birth is characterized by the enrichment of Proteus and the decrease of Bacteroides and Lactobacilli.The decrease of total short chain fatty acids and acetic acid caused by low abundance of Bacteroides and Lactobacillus may lead to premature delivery with cognitive impairment.