Protective Effect Of Ursodeoxycholic Acid On Isoniazid- And Rifampicin- Induced Mice Liver Injury

Objective Based on the mice model of isoniazid (INH) and rifampicin (RFP) -induced liver injury, we observe the protective effect of ursodeoxycholic acid (UDCA), and explore the antioxidant and antiapoptosis effects of UDCA.Methods To observe liver injury induced by isoniazid and rifampicin in mice, forty mice were randomly divided into control group and isoniazid + rifampicin group, treated with 0.9% sodium chloride 10ml/(kg·d), isoniazid 75 mg/(kg·d)+ rifampicin150 mg/(kg·d). The mouse was killed on 14th day. Serum serum alanine aminotransferase (ALT) , aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TB) , conjugated bilirubin (DB), total bile acid (TBA) , body weight, liver index, liver apoptosis and tissues homogenate GSH, MDA were measured. Histological analysis was carried out to assess the injury of the liver.To observe the protective effect of UDCA on isoniazid- and rifampicin- induced liver injury. All mice were randomly divided into control group(CON), isoniazid + rifampicin group(IR) , ursodeoxycholic acid group(UDCA) , low dose of UDCA-pretreatment group(UL), moderate dose of UDCA-pretreatment group(UM) and high dose of UDCA-pretreatment group (UH), twenty mice each group. Mice in control group were treated with saline. Mice in UDCA group were treated with ursodeoxycholic acid (150 mg/kg, i.g.). Mice in isoniazid and rifampicin group were treated with isoniazid (75 mg/kg, i.g.) and rifampicin (150 mg/kg, i.g.). Mice in UDCA protective groups were treated with UDCA (15, 50, 150 mg/kg, i.g.) 30 min before isoniazid and rifampicin. The mice were killed on 14th day. Serum ALT, AST, ALP, TB, DB, TBA, liver index and tissues homogenate GSH, MDA were measured. Histological analysis was carried out to assess the injury of the liver. Immunohistochemistry was used to detect the expression of the hepatic nitrotyrosine (3-NT).To observe the antiapoptosis effect of UDCA on isoniazid- and rifampicin- induced liver injury. All mice were randomly divided into control group(CON), isoniazid + rifampicin group(IR),ursodeoxycholic acid group(UDCA) , high dose of UDCA-pretreatment group(UH). Mice in control group were treated with saline. Mice in isoniazid and rifampicin group were treated with isoniazid (75 mg/kg, i.g.) and rifampicin (150 mg/kg, i.g.). Mice in UDCA group were treated with ursodeoxycholic acid (150 mg/kg, i.g.). Mice in high dose of UDCA protective group were treated with UDCA (150 mg/kg, i.g.) 30 min before isoniazid and rifampicin. The mouse was killed on 14th day. TUNEL was used to detect liver apoptosis; western blotting was used to detect Bax, Bcl-2 protein expression levels; Immunohistochemistry was used to detect the expression of the hepatic caspase-3.Results Compared with control group, in isoniazid and rifampicin group, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TB), conjugated bilirubin (DB), total bile acid (TBA), body weight and liver index (LI) were obviously elevated. Hepatic histology showed steatosis associated with mild necrosis and inflammation. Isoniazid and rifampicin induced lipid peroxidation (MDA) and glutathione (GSH) depletion in mouse liver. Isoniazid and rifampicin increased the number of TUNEL-positive cells in mouse liver.UDCA pretreatment significantly decreased serum ALT, AST and ALP, didn't decrease serum TB, DB and TBA, simultaneously with significantly decreased body weight, liver weight and liver index. UDCA pretreatment significantly attenuated isoniazid- and rifampicin- induced lipid peroxidation (MDA) and glutathione (GSH) depletion. The protect effects of UDCA on isoniazid and rifampicin induced hepatic injury were showed dose - effect manner. UDCA pretreatment significantly ameliorated histopathological change. Correspondingly, results showed that UDCA pretreatment significantly blocked isoniazid and rifampicin induced upregulation of 3-NT in liver.High dose of UDCA pretreatment significantly decreased the number of TUNEL-positive cells in mouse liver; inhibited isoniazid- and rifampicin- induced hepatic Bax expression, and upregulated Bcl-2 expression. Furthermore, UDCA pretreatment significantly blocked isoniazid and rifampicin induced upregulation of caspase-3.Conclusions These results suggest that a fourteenth-day administration of isoniazid and rifampicin causes liver damage. UDCA can protect isoniazid and rifampicin induced liver damage. The protect mechanism of UDCA on hepatic injury induced by isoniazid and rifampicin may be related with antioxidation and antiapoptosis.