High-Fat-Diet-Induced Hyperglycemia Alters Liver Extracellular Matrix Composition in Mice Model

Regenerative medicine integrates interdisciplinary approaches towards restoring the function of diseased organs. This study examined alterations that occurred in the liver under a high-fat diet (HFD) with the development of obesity and fatty liver, and changes in metabolic homeostasis and glucose levels, in mice. HFD nutrition causes hyperglycemia, leading to the formation and accumulation of advanced glycation end-products (AGEs) promoting protein post-translational modifications (PTMs) and introducing crosslinking in the extracellular matrix (ECM). Using histological and gene expression analyses, we detected an increase in adiposity, as well as in ECM protein deposition in the liver. Further, decellularization of the liver yielded the isolated ECM organ scaffold, allowing us to analyze the chemical modification in proteins by various imaging methods combined with spectroscopy. The measurements of intrinsic protein fluorescence are consistent with increased AGE-associated levels. SEM allows for the visualization of ECM fiber thickening as a result of protein crosslinking. Using cathodoluminescence, a label-free imaging method, we confirmed the protein modifications. The combination of innovative technologies highlights the ECM structural alterations associated with impaired glucose regulation and liver adiposity. These findings provide novel views on liver-scaffold ECM structure under metabolic diseases that will play a significant role in accelerating the understanding of effective regenerative therapies.