Elucidation of CYP Inducibility and Inflammatory Response via Cytokine Release in Non-Alcoholic Fatty Liver Disease

Abstract

Non-alcoholic fatty liver disease (NAFLD) is an emerging global health issue that has recently reached 20% in global prevalence and is projected to be the main cause of liver morbidity in the next decade. The lack of accurate human-relevant in vitro systems has caused a barrier in drug development and in the study of cytochrome P450 enzyme expression under hepatosteatotic conditions. Enzyme families CYP1, CYP2, and CYP3 are responsible for the metabolism of more than 60% of all clinically relevant drugs and so, with the growing prevalence of NAFLD, it is likely that NAFLD patients exhibit alterations in these vital drug-metabolizing enzymes and may have risk for harmful drug-drug interactions (DDIs). Here, an in vitro model of NAFLD was engineered using primary human hepatocytes to incorporate clear markers of NAFLD in its progression to non-alcoholic steatohepatitis (NASH) such as inflammation and lipid accumulation. Primary human hepatocytes were cultured in a collagen sandwich configuration that present visible and quantifiable lipid accumulation while maintaining viability and hepatic differentiation over 7 days of cultures and expressing biological markers of NAFLD. Pro-inflammatory cytokines MCP-1, IP-10, IL-8, and VEGFa displayed significant upregulation in the Steatotic states as compared to the Healthy control. These changes were accompanied by significant downregulation of CYP3A4 and CYP1A1 expression and upregulation of CYP2B6 expression in Steatotic cultures upon drug exposure. As there are no approved drug treatments available for NAFLD, this study will give insight into how the diseased state of the liver may affect the metabolism of drugs taken by patients diagnosed with NAFLD.