Expression and significance of TGF-β1, p38MAPK and BMP-7 protein in liver specimens of patients with alveolar hepatic echinococcosis

Abstract

To detect the expression of transforming growth factor-β1 (TGF-β1), p38MAPK and bone morphogenetic protein-7 (BMP-7) protein in the liver specimens of patients with hepatic alveolar echinococcosis, and to investigate the potential role of TGF-β1, p38MAPK and BMP-7 protein in hepatic fibrosis caused by hepatic alveolar echinococcosis. A total of 20 patients with hepatic alveolar echinococcosis were enrolled as study subjects, and hepatic specimens were sampled from the sites within 0.5 cm (Group A) and 0.5 to 1.5 cm from hepatic alveolar echinococcosis lesions (Group B), while normal liver specimens sampled from the sites 2 cm and greater from hepatic alveolar echinococcosis lesions served as controls (Group C). The fibrosis of liver specimens was pathological examined using HE and Masson staining, and the expression of TGF-β1, p38MAPK and BMP-7 protein was quantified in liver tissues using Western blotting. The associations of TGF-β1, p38MAPK and BMP-7 protein expression with hepatic fibrosis were assessed. HE staining showed the malaligned structure of hepatocytes and destruction of the structure of hepatic lobules at various degrees in liver specimens in groups A and B, with hepatocyte degeneration, atrophy and necrosis, hyperplasia of fibrous tissues and eosinophilic granulocyte infiltration seen, while no abnormal pathological alterations of liver tissues, normal hepatocyte structure and morphology and uniform size, no malaligned structure of hepatocytes, clear structure of hepatic lobules, no or mild hepatocyte degeneration or necrosis, and no eosinophilic granulocyte infiltration were seen in Group C. Masson staining showed that there was hyperplasia of multiple fibrous connective tissues in the liver portal areas in groups A and B, with fibrosis seen in hepatic lobules, while no obvious pathological changes were seen in Group C. There were significant differences seen in TGF-β1 (P < 0.001), p38MAPK (P < 0.01) and BMP-7 protein (P < 0.05) expression in liver tissues in groups A, B and C, and higher TGF-β1, p38MAPK and BMP-7 protein expression was quantified in groups A and B than in Group C (all P values < 0.05), while greater TGF-β1, p38MAPK and BMP-7 protein expression was detected in Group B than in Group C (all P values < 0.05). The expression of TGF-β1, p38MAPK and BMP-7 protein correlated positively with the severity of hepatic fibrosis (r = 0.866, 0.702 and 0.801, all P values < 0.05), and there were significant differences in TGF-β1 (F = 72.580, P < 0.01), p38MAPK (χ2 = 31.705, P < 0.01) and BMP-7 protein expression (χ2 = 48.388, P < 0.01) among liver tissues with different degrees of fibrosis. The TGF-β1 protein expression correlated positively with p38MAPK and BMP-7 protein expression (r = 0.607 and 0.702, both P values < 0.001), and the BMP-7 protein expression also correlated positively with p38MAPK protein expression (r = 0.456, P < 0.001). The interaction among TGF-β1, p38MAPK and BMP-7 jointly participates in the development of hepatic fibrosis induced hepatic alveolar echinococcosis.