MgIG Attenuates Oxaliplatin-induced Hepatotoxicity through Suppression of Connexin 43 in Hepatic Stellate Cells

BACKGROUND AND AIMS: Oxaliplatin is widely used in cancer chemotherapy with adverse effects such as liver toxicity. Magnesium isoglycyrrhizinate (MgIG) has hepatoprotective effects, but the underlying mechanism remains elusive. The study’s aim was to investigate the mechanism underlying the hepatoprotective effects of MgIG against oxaliplatin-induced liver injury. METHODS: A xenografted colorectal cancer mouse model was established with MC38 cells. Mice were given oxaliplatin (6 mg/kg/week) for 5 weeks to mimic oxaliplatin-induced liver injury in vivo. LX-2 human hepatic stellate cell s(HSCs) were employed for in vitro studies. Serological tests, hematoxylin and eosin staining, oil red O staining and transmission electron microscopy were used for histopathological examinations. Real-time PCR, western blotting, immunofluorescence and immunohistochemical staining were used to determine Cx43 mRNA or protein levels. Flow cytometry was used to assay reactive oxygen species (ROS) and mitochondrial membrane. Short hairpin RNA targeting Cx43 was lentivirally transduced in LX-2 cells. Ultra-high performance liquid chromatography-tandem mass spectrometry was used to determine MgIG and metabolite concentration. RESULTS: MgIG (40 mg/kg/day) treatment significantly reduced serum aspartate transaminase (AST) and alanine transaminase (ALT) levels in the mouse model, and alleviated liver pathological changes, including necrosis, sinusoidal expansion, mitochondrial damage, and fibrosis. MgIG reduced the abnormal expression of Cx43 in the mitochondria and nuclei of HSCs. MgIG inhibited the activation of HSCs via reducing ROS generation, mitochondrial dysfunction, and N-cadherin transcription. MgIG’s inhibition of HSCs activation was abolished after knockdown of Cx43 in LX-2 cells. CONCLUSIONS: Cx43 mediated MgIG’s hepatoprotective effects against oxaliplatin-induced toxicity.