The Mechanism Study Of Berberine Of Anti-inflammatory And Regulating Intestinal Microbes In Mice Model Of Type 2 Diabetes

[Objective] Berberine(BBR)is a broad-spectrum antibacterial that has been revealed it can play a role of decrease fasting plasma glucose(FPG)in type 2 diabetes mellitus(T2DM)patients,its hpyerglycemic mechanism is worth further study.This study aimed to determine the pharmacological effect of BBR in anti-inflammatory and adjusting intestinal microflora in mice model of T2 DM that for provide an experimental basis in diabetes research.[Method] High-fat diet(HFD)and low doses of streptozotocin(STZ)were used to induce mice model of type 2 diabetes.The experimental mice were randomly divided into 4groups: normal control group(Control),mice model of type 2 diabetes group(T2DM models),T2 DM mice by BBR intragastrical administration group(T2DM+BBR ig)and T2 DM mice by intraperitoneal injection of BBR group(T2DM+BBR ip).Starting from the mice model of T2 DM successful established,T2DM+BBR ig and T2DM+BBR ip group of mice were continuous treated with BBR for 6 weeks,the normal control and T2 DM models group were treated with physiological saline as control.Bacteria plate count method was used to determine the changes of Enterobacter,Enterococcus,Lactobacillus,Bifidobacterium andBacteroides;FPG level was determined by Glucose Oxidase method;Fasting insulin(FIns),IgG and IgA levels were tested by ELISA method;mRNA levels of TLR4,TNF-?,IL-1? and IL-6 in pancreas were detected by real-time fluorescence quantification PCR(qRT-PCR);H&E and immumohistochemical staining were used to test the pathological damage and the degree of macrophages(M?s)infiltration in pancreatic islets.Forthermore,THP-1 derived M?s were cultivated,western-blot was used to test the changes of TLR4 level and NF-?B nuclear transposition;the mRNA levels of TLR4,TNF-?,IL-1? and IL-6 were determined by q RTPCR.[Result] The levels of FPG,FIns,IgA,and mRNA levels of TLR4,TNF-?,IL-1? and IL-6 in pancreas of T2 DM mice were significantly increased compared with normal control,P<0.01;the pathological damage and degree of M?s infiltration in pancreatic islets of T2 DM mice were significantly accentated compared with normal control;meanwhile,the numbers of Enterobacter,Enterococcus were markedly increased,P<0.01,and the amounts of Lactobacillus,Bifidobacterium,Bacteroides were decreased significantly in the intestinal tract of T2 DM mice,P<0.01.After administration of BBR,the levels of FPG,FIns,IgA,mRNA levels of TLR4,TNF-?,IL-1?,IL-6 in pancreas of T2 DM mice were markedly decreased,P<0.05;the pathological damage and degree of M?s infiltration in pancreatic islets of T2 DM mice were markedly alleviated;at the same time,the numbers of Enterobacter,Enterococcus were markedly decreased,P<0.05,but the numbers of Lactobacillus,Bifidobacterium,Bacteroides were increased significantly,P<0.05.Among of them,the FPG levels in T2DM+BBR ip group were decreased faster than T2DM+BBR ig group,but the changes amplitude of intestinal microbes in T2DM+BBR ip group were lower than T2DM+BBR ig group.In addition,the IgG levels in serum were no significant change between four different groups,P>0.05.After BBR treatment for 6 weeks,all of the indicators of T2 DM mice were closed to normal level.In vitro studies have shown that BBR could down-regulate the activation of LPSTLR4 signaling pathway,reduce the mRNA levels of TLR4,TNF-?,IL-1?,IL-6 and block nuclear transposition of NF-?B,P<0.05.The pharmacological functions of BBR 10 ?M were significantly greater than the BBR 5 ?M,P<0.05.[Conclusion] BBR could reduce systemic lowgrade inflammation of T2 DM mice to alleviate diabetes,the effect may be through regulating gut microbes or inhibiting TLR4-NF-?B signaling pathway.