Protective effects of bicyclol on liver fibrosis induced by carbon tetrachloride

Abstract

To study the protective effects and related mechanism of bicyclol on liver fibrosis induced by carbon tetrachloride (CCl(4)). Forty male Wistar rats were injected subcutaneously with 25% CCl(4) twice a week for 3 months. Since the 7th week the rats were divided into 4 groups of 10 rats: normal control group, CCl(4) model group, bicyclol 100 mg/kg group (perfused of bicyclol into stomach 100 mg/kg qd for 45 days), and bicyclol 200 mg/kg group (perfused of bicyclol into stomach 200 mg/kg qd for 45 days). Twenty-four hours after the last administration the rats were killed. The serum was isolated to measure the levels of alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TB), albumin/globulin (A/G), total protein (TP), hyaluronic acid (HA), and pro-collagen peptide III (PIIIP). Serum TNF alpha content was examined by ELISA assay, and liver TGF beta 1 level was determined by immunohistologic assay. The pathology of liver was examined. Twenty-eight mice were divided into 4 groups of 7 mice: normal control group, subacute group, 100 mg bicyclol group (perfused of bicyclol into stomach 50 mg/kg bid), and bicyclol 200 mg/kg group (perfused of bicyclol into stomach, 100 mg/kg bid), and 200 mg bicyclol group. Carbon tetrachloride was injected subcutaneously to the mice in the latter 3 groups every 3 days for 1 month. Twenty-four hours after the last administration the mice were killed and the serum was isolated to measure the levels of ALT, AST, TP, and albumin. Mitochondria were extracted from the livers of the experimental animals to measure the amount of protein. Mitochondrial glutathione (GSH) and malondialdehyde (MDA) contents were measured. The MDA and GSH contents in the control group were regarded as 100%, and the percentages of MDA and GSH in other groups were calculated. The fluidity of mitochondrial membrane and swelling degree of mitochondria were measured. Imunohistochemistry was used to detect the liver TGF beta 1. Nuclear NF kappa B DNA binding activity was investigated by electrophoretic mobility shift assay. Three months after the administration of carbon tetrachloride the serum ALT, AST, TB, HA, and PIIIP levels of the CCl(4) model group increased by 24, 10, 8, 28, and 4 times and the levels of albumin and A/G decreased significantly in comparison with those of the normal control group. However, the serum ALT, AST, TB, HA, and PIIIP levels in the 2 bicyclol groups were significantly lower than those in the model group. The pathological changes in the liver of the 2 bicyclol groups were significantly lighter than those in the model group. The serum TNF alpha increased significantly in the model group, however, the serum TNF alpha levels in the 2 bicyclol groups were significantly lower than that of the model group. The liver TGF beta 1 level in the model group was 4 times that of the normal control group. The liver TGF beta 1 level in the 2 bicyclol groups were significantly lower than that of the model group. One month after the administration of carbon tetrachloride to mice the serum ALT and AST increased and A/G decreased significantly. However, in the 2 bicyclol groups the serum ALT and AST were significantly lower and the A/G ratio was significantly higher in comparison with the model group. The mitochondrial GSH decreased by 34% and the mitochondrial MDA increased by 60% in the model group. The mitochondrial GSH was normal in the 2 bicyclol groups and the MDA level was significantly lower than that of the model group. The fluidity and swelling ability of mitochondrial membrane significantly decreased in the model group mice and the fluidity and swelling ability of mitochondrial membrane in the 2 bicyclol group mice were relatively normal. Twelve and twenty-four hours after the damage by carbon tetrachloride the binding activity of nuclear NF kappa B remained very high in the model group mice and was significantly lower in the 2 bicyclol group mice in comparison with the model mice. Bicyclol alleviates CCl(4)-induced liver fibrosis by its anti-peroxidation and anti-inflammation functions and regulation of NF-kappa B DNA-binding activity.