The Pharmacological Effect Of Sub-dose Doxycycline On Nonalcoholic Steatohepatitis

Objective:To explore the pharmacological effect and mechanism of sub-dose Doxycycline(Dox)on nonalcoholic steatohepatitis(NASH).Method:In the first part,rat islets were cultured in vitro,and DOX was used to stimulate islets and detect the content of insulin secreted by islet tissue.Fourteen 15 week old d B / db mice were randomly divided into model group(model group,n = 7)and drug intervention group(DOX group,n = 7);C57 mice were used as normal control group(NC group,n =6).NC group mice were fed with maintenance feed;Model and DOX groups were fed with methionine choline deficiency(MCD)diet for 4 weeks to establish MCD-NASH model.Dox group was given doxycycline(12 mg / kg)by gavage,and NC and model were given normal saline by gavage.The body weight of the animals was measured twice a week,and the fasting blood glucose of the animals was measured once every two weeks.Four weeks after administration,the serum of mice was taken for blood biochemical detection,and the liver sections of mice were stained with he,oil red O and Sirius red.The expressions of stearoyl COA Desaturase-1(scd-1),acyl Co A oxidase 1(acox1)and fatty acid transporter(CD36)in hepatocytes were measured,and the contents of glucose and lipid metabolism related factors in plasma were detected.In the second part,33 17 week old male ob / ob mice were randomly divided into model group(model group,n = 9),low dose drug intervention group(low DOX group,n= 12)and high dose drug intervention group(high DOX group,n = 12);C57 mice were used as normal control group(NC group,n = 8).NC group mice were fed with maintenance diet;Model,low DOX and high DOX groups were fed with GUBRA starch cellulose Nash(GAN)feed for 10 weeks to establish GAN-NASH model;The low DOX group was given a subclinical dose of DOX(15 mg / kg)per day,the high DOX group was given a subclinical dose of DOX(30 mg / kg)per day,and NC and model were given a normal saline per day.The weight and diet of animals were measured once a week,and the blood glucose of animals was measured once two weeks.Ten weeks after administration,the serum of mice was taken for blood biochemical detection,and the weights of liver,epididymal fat,kidney and spleen were weighed.The liver slices of mice were stained with he and Sirius red,and the contents of glucose and lipid metabolism related factors and cytokines in plasma were detected.Result:1.DOX can promote the secretion of insulin in isolated rat islets.Dox intervention reduced the levels of triglyceride(TG),alkaline phosphatase(ALP),lactate dehydrogenase(LDH)and low density lipoprotein cholesterol(LDL-C)in serum of MCD-NASH mice,promoted the secretion of gastric inhibitory peptide(GIP),glucagon like peptide-1(GLP-1)and insulin,reduced the area of lipid droplets in hepatocytes and the expression level of CD36 m RNA in liver.2.DOX intervention in both high-dose and low-dose groups decreased the random blood glucose and diet of GAN-NASH mice,reduced the weight of spleen,reduced the level of serum lipase(LPS)and reduced the expression of IL-17 A.DOX in high-dose group promoted the secretion of ghrelin,leptin and GIP,while DOX in low-dose group promoted the secretion of ghrelin.The hepatic fibrosis of DOX in high and low dose groups was significantly reduced in a concentration gradient dependent manner.Conclusion:Sub-dose DOX(12 mg / kg)improved hepatic steatosis in MCD-NASH mice;At the same time,reduce the blood lipid level,reduce the damage of lipid accumulation to hepatocytes,improve liver function,protect the liver,and regulate the disorder of lipid metabolism in mice.Compared with MCD-NASH mice,GAN-NASH mice had fibrosis,and 30 mg / kg DOX significantly improved the fibrosis of GAN-NASH mice;Sub-dose DOX(15mg / kg,30 mg / kg)has a Glucose dependent hypoglycemic effect in GANNASH mice.It can inhibit appetite,Protect the pancreas and maintain the normal quality of the spleen,reduce inflammatory factors in plasma and improve the abnormal glucose and lipid metabolism of NASH.This study provides a theoretical basis for the development and utilization of DOX in the research of Nash drugs.