Study on the nuclear mechanotransduction in aligned VSMC tissue on a microgrooved collagen substrate

Abstract

Vascular smooth muscle cells (VSMCs) change their phenotype from contractile to synthetic under pathological conditions. A similar change is observed when VSMCs are isolated from the native tissue and placed in culture conditions. To understand smooth muscle pathophysiology, it is important to understand the mechanism of their phenotypic change. We previously found that actin stress fibers (SFs) in VSMCs have a mechanical interaction with the nucleus, and the internal forces of SFs were transmitted directly to the nucleus. Thus, it is possible that the nuclear-cytoskeletal interactions and their force transmission efficiently could be associated with VSMC differentiation. In this study, we developed a novel micro-grooved collagen substrate to control cell orientation similar to in vivo vascular tissue, and cultured VSMCs on this substrate to induce their contractile differentiation. Then we investigated the mechanical environment of the nucleus, and assessed the changes in the nuclear-cytoskeletal interactions during smooth muscle differentiation.