黄连-肉桂对db/db小鼠肠道菌群及内毒素影响的研究

Effects of coptis-cinnamon on intestinal microflora and endotoxin in db/db mice

目的研究黄连-肉桂对db/db小鼠血糖、肠道菌群及脂多糖(LPS)的影响。方法取6只db/m小鼠为正常组,将30只db/db小鼠随机分成模型组、二甲双胍组、黄连组、肉桂组、黄连-肉桂组各6只。正常组和模型组给予生理盐水灌胃,其余组给予相应药物灌胃8周。灌胃前(0周)及灌胃后每周测量各组小鼠的体重,在灌胃前及灌胃4周、8周后分别测量各组小鼠的血糖;灌胃8周后采集各组小鼠粪便,16S-rDNA高通量测序对肠道菌群进行基因测序;眼球采血,酶联免疫法检测血清中LPS含量。结果各药物组小鼠体重增长趋势均减缓,黄连-肉桂组体重增长减缓最明显。各药物组小鼠血糖呈明显下降趋势,黄连-肉桂组血糖下降趋势最明显;灌胃8周后黄连组和黄连-肉桂组小鼠血糖均明显低于二甲双胍组和肉桂组(P均<0.05),黄连组和黄连-肉桂组比较差异无统计学意义(P>0.05)。与模型组及二甲双胍组比较,黄连组、肉桂组、黄连-肉桂组小鼠粪便中后壁杆菌门(Firmicutes)丰度明显下降,其中黄连-肉桂组下降最明显;黄连-肉桂组拟杆菌门(Bacteroidetes)、放线菌门(Actinobacteria)、变形杆菌门(Proteobacteria)及疣微菌门(Verrucomicrobia)丰度明显增加。灌胃8周后各药物组血清LPS含量均较模型组明显降低(P均<0.05),各药物组间比较差异均无统计学意义(P均>0.05),但黄连-肉桂组最低。结论黄连-肉桂可以有效降低db/db小鼠血糖,其降糖机制可能与有效调节小鼠肠道菌群及减少LPS释放入血有关。

Objective It is to study the effects of coptis-cinnamon on blood sugar,intestinal microflora and lipopolysaccharide(LPS)in db/db mice.Methods Six db/m mice were taken as normal group,and another 30 db/db mice were randomly divided into model group,metformin group,coptis group,cinnamon group,coptis-cinnamon group,6 mice in each group.The normal group and the model group were given normal saline by gavage,and the other groups were treated with corresponding drugs by gavage for 8 weeks.The body weight of the mice in each group was measured before(0 week)and every week after gavage.The blood glucose of the mice in each group was measured before gavage and 4 weeks and 8 weeks after gavage;after 8 weeks of intragastric administration,the feces of the mice in each group were collected,the gene sequence of the intestinal flora was detected by 16S-rDNA high-throughput sequencing;the blood was collected from the eyeballs to detected the LPS content in the serum by enzyme-linked immunoassay.Results The increase trend of body weight of the mice in each treatment group all slowed down,and the slowing was the most obvious in coptis-cinnamon group.The blood glucose of mice in each treatment group showed a significant downward trend,and the downward trend of blood sugar of coptis-cinnamon group was the most obvious.After 8 weeks of intragastric administration,the blood glucose of mice in the coptis group and coptis-cinnamon group was significantly lower than that of the metformin group and cinnamon groups(all P<0.05),there was no significant difference between the coptis group and coptis-cinnamon group(P>0.05).Compared with the model group and the metformin group,the abundance of Firmicutes in the feces of mice in the coptis group,cinnamon group and coptis-cinnamon group was decreased significantly,and the decrease in the coptis-cinnamon group was the most significant;the abundance of Bacteroidetes,Actinobacteria,Proteobacteria and Verrucomicrobia was increased significantly in coptis-cinnamon group.After 8 weeks of intragastric administration,the content of LPS in serum in each treatment group was significantly lower than that of the model group(all P<0.05),and there was no significant difference among the treatment groups(all P>0.05),but the that in the coptis-cinnamon group was the lowest.Conclusion Coptis-cinnamon can effectively reduce blood sugar in db/db mice,and its hypoglycemic mechanism may be related to the effective regulation of the intestinal flora of mice and the reduction of LPS release into the blood.