Matrix stiffness modulates YAP-mediated glycolysis and proliferation in human corneal endothelial cells

Human corneal endothelium (HCE) plays a vital role in preserving corneal transparency and thickness. However, a marked reduction in the cell density can result in functional decompensation, potentially leading to blindness. The scarcity of donor corneas has limited the development of clinical interventions for this condition, therefore, developing highly functional tissue-engineered HCE (TE-HCE) important. The construction of TE-HCE fundamentally relies on modulating the mechanical microenvironment of the scaffold, which is essential for promoting the optimal proliferation and metabolic activity of the seeded cells. In this study, we used polyacrylamide hydrogels with stiffnesses of 25, 50, and 100 kPa to simulate the mechanical properties of Descemet's membranes and explore the regulatory role of matrix stiffness in HCE cell metabolism and proliferation. An increased scaffold stiffness promoted the proliferation of HCE cells by enhancing the mechanical response of HCE cells, increasing the nuclear translocation of Yes-associated protein (YAP), and promoting the expression of downstream proliferation regulatory genes. Increasing the stiffness of the scaffold also enhanced the glycolysis level of HCE cells by promoting the expression of key glycolytic enzymes, thereby improving the viability and energy yield of HCE cells. Notably, the variations in scaffold stiffness could influence cell proliferation via the YAP pathway by modulating the glycolysis levels, potentially establishing the positive feedback of "metabolic response-proliferation." This study elucidates the regulatory mechanisms by which mechanical microenvironments influence cellular functions, and provides a theoretical foundation and technical support for the development of tissue-engineered products with precise mechanical properties.