Study On Gegen Qinlian Decoction Intervention Of Short-chain Fatty Acids In Intestinal Microflora Of Pre-diabetic Rats

Objective:Hyperlipidemia(HLP)is the initiating factor of glucose metabolism disorder,which can promote the occurrence of insulin resistance.Therefore,monitoring the level of lipid metabolism can prevent the occurrence of type 2 diabetes.Classic prescription intervention in HLP may be an important mean to prevent and control the development of type 2 diabetes.Gut flora producing short chain fatty acids(SCFAs)plays an important role in glycolipid metabolism.The mechanism of intestinal flora is rarely reported.In order to better prevent and control HLP and prevent diabetes,this subject first established the HLP rat model,on this basis,the clinical treatment of intestinal damp-heat type 2 diabetes with significant curative effect of Gegen Qinlian Decoction(GQD)intervened to investigate the mechanism of GQD on the intestinal flora(SCFAs)under the clear lipid-lowering effect of GQD.Methods:Rats were given 60% fat content high-fat feed to establish an obese HLP model.After successful modeling,GQD intervention therapy was performed for 11 weeks.Body weight and body length were collected at various time points and Lee’s index was calculated.TC,HDL-C,LDL-C),fasting blood glucose(FBG)and fasting insulin(FIns),calculate the insulin index,perform multiple linear regression analysis;establish a gas chromatography(GC)method to detect SCFAs,and detect four time points(Before dosing,dosing for 5 weeks,dosing for 7 weeks and dosing for 11 weeks)acetic acid,propionic acid and butyric acid content,and calculate the ratio of short-chain fatty acids;intestinal flora 16 S r RNA V3-V4 region sequenced In the R language,the two-part model was used to analyze the association between blood glucose,lipid,SCFAs phenotype and intestinal flora OTU level;finally,PICRUSt software was used to analyze the potential microbial gene function and KEGG metabolic pathways on intestinal flora data.Results:1.After 5 weeks of modeling,compared with the blank control group,the body weight and Lee’s index of the high-fat diet group increased significantly(P<0.01);the TC,TG and LDL-C of the high-fat diet group were significantly higher than the normal group(P<0.01),showing that the model of obese HLP rats was successful.Compared with the model group,after 5 weeks of administration,the positive drug simvastatin group,high,medium and low doses of GQD all had a significant reduction effect on TG of high-fat diet rats(P<0.01),and the TC content of the GQD high and low dose groups also decreased significantly(P<0.05);after 7 weeks of administration,the TC and TG of the GQD high,medium and low dose groups were significantly reduced(P<0.05),HDL-C in the GQD middle-dose group was significantly reduced(P<0.05);after 11 weeks of administration,the TC in the GQD middle-dose group was significantly reduced(P<0.05),while the GQD was high The TG of rats in the three dose groups,medium and low were significantly reduced(P<0.01).At the same time,FBG began to increase significantly(P<0.05),while high-dose GQD had a significant reduction effect(P<0.05),and each administration group had no significant effect on LDL-C,FIns,IR index and other indicators(P>0.05).The results of multiple linear regression analysis showed that BW,BL,Lee ’,TC,TG,HDL-C,LDL-C,FBG,FIns before administration and 11 weeks after administration were all correlated with the insulin resistance index.2.Compared with the blank control group,the content of acetic acid,propionic acid and butyric acid in the obese HLP group decreased significantly at four time points(P<0.05).After 5 weeks of GQD administration,the rats in the HLP model group In contrast,GQD low-dose treatment significantly increased fecal acetic acid content,and GQD low-dose increased fecal propionic acid content;7 weeks after administration,GQD medium-and high-dose significantly increased fecal acetic acid content.After 11 weeks of administration,the content of acetic acid in the cecal contents of the low,medium and high dose groups of GQD all showed a downward trend,GQD medium and high doses significantly reduced the content of propionic acid in the cecum content,GQD three dose groups significantly reduced the content of butyric acid in the cecum content;compared with the blank group,HLP model group rat acetic acid/propionic acid ratio Significantly decreased(P<0.05),while the contents of propionic acid/butyric acid and acetic acid/butyric acid increased significantly(P<0.05).GQD mid-dose showed better efficacy,and GQD mid-dose group acetic acid/propionic acid was significantly increased(P<0.01),Propionic acid/butyric acid significantly decreased(P<0.01).3.23 OTUs related to blood lipids(TC,TG)were identified;43 OTUs related to blood glucose;3 OTUs shared by TC and TG(OTU559,701,and 135)were annotated as g＿norank＿f＿Peptococcaceae,g＿Anaerotruncus＿f＿Ruminococcaceae and g＿Peptoclostridium＿f＿Peptostreptococcaceae,of which OTU135 is also shared by fasting bloodglucose.The OTUs related to SCFAs(acetic acid,propionic acid,and butyric acid)were 62,77,and 65,of which 36 OTUs were shared by SCFAs.4.At Level 2,a total of 7,3 and 2 KEGG pathways were identified as positively correlated with acetic acid,propionic acid and butyric acid,and 3,25 and 28 KEGG pathways were identified as negatively correlated with acetic acid,propionic acid and butyric acid.At Level 3,a total of 40,28 and 22 KEGG pathways were identified as positively correlated with acetic acid,propionic acid and butyric acid,and 23,173 and 173 KEGG pathways were identified as negatively correlated with acetic acid,propionic acid and butyric acid(FDR<0.05).Conclusions:1.Feeding rats with 60% high-fat feed can establish a fast and stable obese HLP rat model;GQD has a down-regulating effect on rat blood lipids(TG,TC),high doses of GQD can prevent blood sugar from rising,and prevent insulin resistance.2.GQD can reduce the risk of diabetes in HLP rats by adjusting the proportion of SCFAs.3.Bacteria associated with SCFAs exhibit multiple functions,including beneficial bacteria,pathogenic bacteria and conditional pathogenic bacteria.4.Potential KEGG pathways in which SCFAs affect intestinal flora include lipid metabolism,amino acid metabolism,carbohydrate metabolism,nucleotide metabolism and other related pathways.