Modulation of micro-RNA and inflammation by Andrographolide in NAFLD pathology

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Project Summary/Abstract: With obesity assuming pandemic proportions across the developed nations (USA, continental Europe) and emerging economies of India and China, it is estimated that 20-30% of this huge population will develop fatty liver disease (NAFLD). A sizable proportion (roughly 120 million) of those affected with NAFLD will have steatohepatitis and the disease progression is believed to be dependent on the built environment and diet. In spite of the enormous health risk, no suitable treatment regimen has been established so far due to the complications of the disease itself, following multiple risk factors of steatosis, metabolic disorder, inflammation and abnormal endocrine function. Andrographolide (ANDL) is a unique plant derivative which has shown profound caloric restriction, anti-inflammatory and metabolic signaling modulation properties. The use of this compound as a preventive and therapeutic agent in NAFLD is of immense importance to this very significant health risk. Importantly, identifying newer epigenetic modulating function of ANDL in NAFLD would go a long way in targeting effective therapy in this disease. In the current study, we will test the central hypothesis that oral administration of andrographolide (ANDL) attenuates NAFLD via its actions on miR-21-induced inflammatory checkpoints in sinusoidal endothelial dysfunction, stellate cell activation, TGF-beta signaling and defective macroautophagy. The long term objective of this project is to design a comprehensive experimental and preclinical evidence of a treatment regimen that derives from natural dietary supplements with proven anti- inflammatory potential against NAFLD. About seventy-five percent of obese subjects have hepatic steatosis, and about 20% of these individuals develop inflammatory liver disease marked by necroinflammation, a rise in inflammatory cytokines, and some degree of fibrosis. This advanced stage of the disease progression often leads to cirrhosis and autoimmune complications because of the highly inflammatory microenvironment. Because NAFLD has been shown to derive its progression and severity from an underlying condition of obesity and hepatic inflammation, it is imperative that Andrographolide, which has a potent anti-inflammatory effect, might restrict the progression of steatosis to steatohepatitis and thwart the development of more severe complications like hepatocellular carcinoma. The novel role of andrographolide as an epigenetic regulator in NAFLD therapy has never been explored. This project will aim to utilize the supplementation of andrographolide in steatotic mice to abrogate the progression of steatohepatitis following methionine choline deficient diet exposure by its effective regulation of miR21 via NFkB inhibition leading to suppression of sinusoidal endothelial dysfunction, inflammation and defective autophagy. This project proposes to utilize the COBRE funds to generate sufficient evidence of andrographolide as a potential anti-inflammatory and epigenetic regulator as part of its therapeutic effect in NAFLD.