Engineered 3D Kidney Glomerular Microtissues to Model Podocyte-Centric Diseases for the Validation of New Drug Targets.

Abstract

Podocytopathies are a diverse group of kidney diseases characterized by podocyte injury, leading to proteinuria and reduced kidney function. This injury often disrupts cytoskeletal dynamics and cellular adhesion, causing glomerular dysfunction. Current in vitro models fail to accurately mimic the three-dimensional (3D) organization and mechanics of kidney tissue, hindering the understanding of podocyte pathophysiology and therapeutic development. In this study, 3D microtissues are developed that replicate the structure and mechanics of the glomerular filtration barrier, enabling the modeling of chemically and genetically induced podocyte injuries for drug target validation. These microtissues simulate the glomerulus's three-layer structure and hemodynamic mechanical stretch, providing a platform to evaluate relevant mechanobiological signaling pathways and podocyte dynamics. Collective cellular forces are measured to assess podocyte resilience against genetic or chemical injuries. As a proof-of-concept, podocyte injury is modeled through transient receptor potantial canonical 6 (TRPC6) overexpression, a validated target in podocytopathies, and evaluated by the TRPC6 inhibitor SAR7334. The results demonstrated a loss of podocyte contractile forces upon TRPC6 overexpression, with recovery following treatment. This highlights the potential of glomerular microtissues to model podocyte mechano-pathophysiology and serves as a robust platform for screening new therapies.