Altered Calcium Flux Drives VSMC Matrix Rigidity Response

Wostear, Finn (2025) Altered Calcium Flux Drives VSMC Matrix Rigidity Response. Doctoral thesis, University of East Anglia.

Preview

PDF Download (27MB) | Preview

Abstract

Arterial stiffening is a key component of cardiovascular disease and ageing. This stiffening is primarily driven by remodelling of the extracellular matrix and the subsequent response of vascular smooth muscle cells (VSMCs). The stiffening of VSMCs in response to enhanced vessel rigidity is termed ‘vascular smooth muscle cell stiffness syndrome (VSMCSS)’ and is regarded as a core component of vessel stiffening. However, the signalling and mechanistic pathways that induce VSMCSS are not well understood. The work in this thesis aims to elucidate the pathways that drive VSMC dysfunction.

I use primary human aortic VSMCs and polyacrylamide hydrogels of tuneable stiffness to mimic the rigidity of the VSMC extracellular environment in health and disease. This assay is used in combination with targeted pharmacological inhibition/activation of key VSMC signalling pathways. Microscopy techniques, such as confocal immunofluorescence microscopy and live-cell video time-lapse microscopy, are used to identify stiffness-dependent responses.

I find that inhibition of key signalling pathways modulates VSMC morphology response to enhanced matrix rigidity. I specifically identify aquaporins as key regulators of the VSMC morphology response to enhanced matrix rigidity. I additionally identify microtubule stability and Ca2+ signalling machinery as vital components in this response. I use the Fluo-4 calcium indicator and live cell time-lapse microscopy to highlight increased Ca2+ flux on rigid matrices. I find that this increased flux can be modulated by targeted inhibition of mechanosensitive ion channels and promotion of microtubule stability. These novel findings highlight the role of Ca2+ as a central integrator of the VSMC response to enhanced matrix rigidity. I additionally examine downstream effectors of VSMC stiffness response to enhanced matrix rigidity and confinement. I highlight the diverse responses of VSMCs through traction stress generation and area/volume regulation.

My findings develop our understanding of VSMCSS and provide novel targets for pharmacological treatment of stiffness-induced VSMC dysfunction.

Item Type:	Thesis (Doctoral)
Faculty \ School:	Faculty of Science > School of Chemistry, Pharmacy and Pharmacology
Depositing User:	Chris White
Date Deposited:	08 Jun 2026 12:54
Last Modified:	08 Jun 2026 12:54
URI:	https://ueaeprints.uea.ac.uk/id/eprint/103316
DOI:

Downloads

Actions (login required)

View Item