The aim of this study is to investigate the effects of the metformin on the formation of hepatic fibrosis in type 2 diabetic rats and discuss its mechanism of liver-protecting activity. After SD rats were fed with high-fat and high-sucrose diet for four weeks, low-dose streptozotocin (STZ) was injected intraperitoneally to make the animal mode of type 2 diabetes. Then, all diabetic rats was fed with the high-fat diet and metformin (ig, 100 mg x kg(-1)) was given orally to metformin group for four months. After the last administration, fasting blood glucose was determined. The livers were removed to calculate the hepatic coefficient and to make HE and Picro acid-Sirius red staining, immunohistochemistry (alpha-SMA and TGFbeta1) and TUNEL staining in order to evaluate the effect of metformin on the hepatic fibrosis. The animal model of type 2 diabetes with hepatic fibrosis was successfully made. Metformin can significantly alleviate the lesions of hepatic steatosis and fibrosis, markedly reduce the expressions of alpha-SMA and TGFbeta1 in liver tissue of type 2 diabetic rats. However, TUNEL staining result suggested that metformin could not reduce apoptosis of hepatocytes. The results suggest that metformin can inhibit the formation of hepatic fibrosis in type 2 diabetes.
Actins ; metabolism ; Animals ; Apoptosis ; drug effects ; Blood Glucose ; metabolism ; Body Weight ; drug effects ; Diabetes Mellitus, Experimental ; drug therapy ; etiology ; metabolism ; pathology ; Diabetes Mellitus, Type 2 ; drug therapy ; etiology ; metabolism ; pathology ; Diet, High-Fat ; Female ; Hepatocytes ; pathology ; Hypoglycemic Agents ; pharmacology ; therapeutic use ; Liver ; metabolism ; pathology ; Liver Cirrhosis, Experimental ; drug therapy ; metabolism ; pathology ; Male ; Metformin ; pharmacology ; therapeutic use ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Streptozocin ; Transforming Growth Factor beta1 ; metabolism

BACKGROUNDS AND AIMS: Angiotensin receptors are found on hepatic stellate cells, which participate in hepatic fibrosis. Therefore, it is presumed that angiotensin has a role in hepatic fibrosis. The aim of this study was to evaluate the effects of angiotensin blockade on inhibition of hepatic fibrosis in cirrhotic rat model. Material and METHODS: Cirrhosis with portal hypertension was produced by common bile duct ligation (BDL) in the adult Sprague-Dawley rats. They were classified into 4 groups (each group n=6) as follows; G1: BDL without drug, G2: BDL+captopril 100 mg/kg/day beginning 2 weeks after BDL, G3: BDL+captopril 100 mg/kg/day, starting just after BDL, G4: BDL+losartan 10 mg/kg/day, starting just after BDL. After 4 weeks following BDL, hepatic fibrosis was histomorphologically analyzed by Batts & Ludwig score. Alpha smooth muscle actin by immunohistochemical stain, hydroxyproline contents of liver tissue by spectrophotometry and expression of collagen, procollagen, and TGF-beta by real-time PCR were measured. RESULTS: Batts & Ludwig score were 3.8, 3.0, 2.6,and 2.6 in G1, G2, G3, and G4, respectively. The expression of alpha-SMA was significantly lower in G3 and G4 than in G1; 11.9%, 10.9%, 2.6%, and 1.1% in G1, G2, G3, and G4, respectively (p<0.05). The concentration of hydroxyproline (microgram/g liver tissue) was lower in G3 and G4 compared with G1 (p<0.05). Also, the administration of angiotensin blockade just after BDL significantly reduced the expression of collagen, procollagen, and TGF-beta mRNA. CONCLUSIONS: Angiotensin blockades are effective in the prevention of hepatic fibrosis in BDL rats.
Actins/metabolism ; Angiotensin II Type 1 Receptor Blockers/administration & dosage/*therapeutic use ; Animals ; Bile Ducts/pathology/surgery ; Captopril/administration & dosage/*therapeutic use ; Fibrosis ; Hydroxyproline/metabolism ; Ligation ; Liver/drug effects/metabolism/pathology ; Liver Cirrhosis, Experimental/*drug therapy/etiology/metabolism ; Losartan/administration & dosage/*therapeutic use ; Male ; Rats ; Rats, Sprague-Dawley ; Transforming Growth Factor beta/metabolism

OBJECTIVETo explore therapeutic effect of Haobieyangyinruanjianfang (HBYYRJ) on mouse liver fibrosis by schistosomiasis.

METHODSMice except for normal control were infected with Japanese schistosome cercarias, after 12 weeks, infected mice were divided into 7 groups: low HBYYRJ group, middle HBYYRJ group, high HBYYRJ group, Fufangbiejiaruangan tablet (FFBJRG) group, colchicine group, 3 months infection group and 6 months infection group. Hepatic fibrosis was found in 3 months infection group. Liver hydroxyproline (Hyp) was determined, matrix metalloproteinase-2 and 9 (MMP-2, MMP-9) were detected with gelatin zymography, serum hyaluronic acid (HA) and precollagen III (PC-III) were detected using RIA.

RESULTSHBYYRJ obviously reduced hepatic fibrosis (probability value less than 0.01). Collagen and HA in 3 months infection group and 6 months infection group were higher than that in normal group (probability value less than 0.01), collagen in high and middle HBYYRJ groups and HA in middle and low HBYYRJ groups were lower than that in 6 months infection group (P less than 0.01, probability value less than 0.05). The expression of MMP-9 and MMP-2 in 3 months infection group and 6 months infection group was higher than that in normal group (probability value less than 0.01), The expression of MMP-9 in three HBYYRJ groups and the expression of MMP-2 in high HBYYRJ group were lower than that in 6 months infection group (probability value less than 0.05).

CONCLUSIONHBYYRJ can reduce liver fibrosis caused by schistosomiasis.

Animals ; Collagen Type III ; blood ; Disease Models, Animal ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; therapeutic use ; Female ; Hyaluronic Acid ; blood ; Hydroxyproline ; metabolism ; Liver ; drug effects ; metabolism ; pathology ; Liver Cirrhosis, Experimental ; drug therapy ; etiology ; metabolism ; pathology ; Male ; Materia Medica ; isolation & purification ; pharmacology ; therapeutic use ; Matrix Metalloproteinase 2 ; metabolism ; Matrix Metalloproteinase 9 ; metabolism ; Mice ; Schistosoma japonicum ; Schistosomiasis japonica ; complications ; Severity of Illness Index ; Sex Factors ; Treatment Outcome