Activation of autophagy is required for Oroxylin A to alleviate carbon tetrachloride-induced liver fibrosis and hepatic stellate cell activation

• Published in: International immunopharmacology 2018-03, Vol.56, p.148-155
• Main Authors: Chen, Weiwei, Zhang, Zili, Yao, Zhen, Wang, Ling, Zhang, Feng, Shao, Jiangjuan, Chen, Anping, Zheng, Shizhong
• Format: Article
• Language: English
• Subjects: Actin; Adenine - analogs & derivatives; Adenine - pharmacology; Alanine; Alanine transaminase; Alkaline phosphatase; Animal models; Animals; Anti-Inflammatory Agents - therapeutic use; Anticancer properties; Aspartate aminotransferase; Autophagy; Biomarkers; Carbon; Carbon Tetrachloride; Cell activation; Cells, Cultured; Cirrhosis; Collagen; Collagen Type I - metabolism; Desmin; Disease Models, Animal; Extracellular matrix; Extracellular Matrix Proteins - metabolism; Fibronectin; Fibrosis; Flavonoids - therapeutic use; Gene expression; Hepatic stellate cell; Hepatic Stellate Cells - drug effects; Hepatic Stellate Cells - physiology; Hepatocytes; Humans; Inflammation; Liver; Liver - drug effects; Liver - metabolism; Liver - pathology; Liver cirrhosis; Liver Cirrhosis - chemically induced; Liver Cirrhosis - drug therapy; Liver fibrosis; Male; Markers; Medical treatment; Mice; Mice, Inbred ICR; Molecular chains; Molecular mechanism; Molecular modelling; Molecular Targeted Therapy; Morbidity; mRNA; Muscles; Natural products; Oroxylin A; Phagocytosis; Pharmacology; Platelet-derived growth factor; Platelet-derived growth factor BB; Protein expression; Proteins; Receptors, Transforming Growth Factor beta - metabolism; Scutellaria baicalensis - immunology; Smooth muscle; Substrates
• ISSN: 1567-5769; 1878-1705
• DOI: 10.1016/j.intimp.2018.01.029

Liver fibrosis is a reversible pathophysiological process correlated with intense repair and cicatrization mechanisms, and its end-stage cirrhosis is responsible for high morbidity and mortality worldwide. Interestingly, the use of natural products as a realistic option for the treatment of liver fibrosis has broadly been accepted. Oroxylin A, a safe and natural product, shows a wide range of pharmacological activities such as anti-inflammatory, anti-oxidant, and anti-tumor properties. However, the effects of Oroxylin A on liver fibrosis remain poorly understood. In the present study, we sought to determine the effect of Oroxylin A on carbon tetrachloride (CCl4)-induced liver fibrosis, and to further examine the molecular mechanisms. We found that treatment with Oroxylin A markedly decreased the level of liver injury markers, alkaline phosphatase (ALP), aspartate aminotransferase (AST), and alanine aminotransferase (ALT), in a dose dependent manner. Moreover, Oroxylin A treatment remarkably inhibited extracellular matrix (ECM) deposition, and significantly down-regulated the mRNA and protein expression of liver fibrosis markers including α1(I)collagen, fibronectin, alpha-smooth muscle actin (α-SMA), PDGF-βR, and TGF-βR1 in CCl4-induced murine model of liver fibrosis. Furthermore, experimental results in vitro showed that Oroxylin A treatment reduced the mRNA and protein expression of HSC activation markers, α-SMA, desmin, α1 (I) collagen, fibronectin, TGF-β, and TNF-α, in a dose dependent manner. Attractively, Oroxylin A treatment also markedly up-regulated the expression of autophagy makers, LC3-B, Atg3, Atg4, Atg5, Beclin1/Atg6, Atg7, Atg9, ATG12, and Atg14, and apparently reduced the expression of autophagy substrate p62 in both CCl4-induced murine model of liver fibrosis and PDGF-BB-treated HSCs. Importantly, inhibition of autophagy by specific inhibitor 3-methyladenine (3-MA) completely abolished Oroxylin A-induced anti-fibrosis effect, indicating that activation of autophagy was required for Oroxylin A to alleviate liver fibrosis. Overall, these results provide novel implications to reveal the molecular mechanism of Oroxylin A-induced anti-fibrosis properties, by which points to the possibility of using Oroxylin A for the treatment of liver fibrosis. •Oroxylin A alleviated carbon tetrachloride-induced liver fibrosis.•Oroxylin A induced autophagy activation in hepatic stellate cells.•Inhibition of autophagy impaired Oroxylin A-induced anti-fibrosis ef