Dietary Fructose Regulates Kupffer Cell Metabolism and Plasticity

Abstract

Over-consumption of fructose in humans have been linked to increased risk of Non-Alcoholic Fatty Liver Disease (NAFLD) and other metabolic diseases. Recent studies have suggested that fructose plays an important role in the development of liver inflammation, fibrosis, and immune cell activation during NAFLD. However, little work characterizes the direct impact of fructose on macrophage infiltration, phenotype, and function in the liver. Our studies demonstrate that chronic fructose exposure induces liver fibrosis and inflammation compared to control and glucose diets . Single cell RNA sequencing (scRNAseq) revealed fructose and glucose reduced Kupffer cells while increasing transitioning monocytes. However, fructose alone significantly increased expression of fibrosis and wound healing associated genes Mmp12, Il1rn, Rsad2, and Gpnmb in Kupffer cells. In vitro studies demonstrated that fructose treated immortalized Kupffer cells (IMKC) metabolize fructose through glycolysis and pentose phosphate pathway (PPP) by stable isotope tracing. Fructose treated IMKC cells showed reduced cell viability and increased Gpnmb, Tnfa, Mmp12, Il1rn, and Rsad2 gene expression. In addition, inhibition of the PPP further increased fructose induced Gpnmb, Mmp12, Il1rn, and Rsad2 in nonpolarized IMKCs. Taken together, fructose decreases cell viability while upregulating wound healing and fibrosis associated genes in Kupffer cells. This study was funded by the R21 DK128678 National Institute of Diabetes and Digestive and Kidney Diseases to AK. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.