Project

Alterations in calcium handling in cardiac fibroblasts from diseased hearts

Supervisor(s)

Area

Target Validation, Cardiovascular, Calcium, Cellular Signalling

Description

Cardiac fibroblasts play a crucial role in maintaining the structural, mechanical and biochemical properties of the healthy heart. Importantly, these cells are also pivotal to the fibrotic remodelling that accompanies cardiovascular disease, impacting upon contractile function. The mechanisms underlying abnormal growth and function of cardiac fibroblasts during the disease process remain incompletely understood. A key element that is important for the healthy function of any cell type is the balance of intracellular calcium handling. Calcium is crucial for so many cellular functions and is probably even more critical in the heart where its role in contraction is central. There is a wealth of research on calcium handling in the muscle cells of the heart but far less is known of how calcium signalling impacts upon cardiac fibroblast function, particularly during disease.

Previous work by our group has explored how cardiac fibroblast function is altered during disease. We found that during conditions of cardiac hypertrophy the fibroblasts of the heart become hyper-proliferative and there is increased activity of calcium/calmodulin dependent protein kinase II (CaMKII). Preliminary work suggests that there may also be changes in intracellular calcium release channels (IP3 receptors) during hypertrophic remodelling and this may impact upon cellular function.

The purpose of this project will be to explore in detail the changes that occur in intracellular calcium channel function and CaMKII activity during disease progression, specifically at the level of the cardiac fibroblast. The project will use a pharmacologically-induced animal model of disease and will use both in vivo and in vitro approaches to examine cardiac function in parallel with cardiac fibroblast function and calcium handling. Alterations in IP3R expression and function will be explored as well as potential changes that may occur in calcium channels located at the plasma membrane (Transient Receptor Potential (TRP) channels).

Techniques

Cardiac echocardiography, tissue isolation, primary cardiac fibroblast isolation and culture, kinase assays, proliferation assays, cell imaging and immunofluorescence, immunoblotting, immunoprecipitation, calcium assays and imaging.

References

Souders C.A. et al (2009) Cardiac Fibroblast the renaissance cell. Circ Res. 105: 1164-1176

Feng N & Anderson M.E. (2017) CaMKII is a nodal signal for multiple programmed cell death pathways in heart. J.Mol.Cell.Cardiol. 103: 102-109

Martin T.P. et al (2014) Adult cardiac fibroblast proliferation is modulated by calcium/calmodulin-dependent protein kinase II in normal and hypertrophied hearts. Pflugers Arch.Eur.J.Physiol. 466: 319-330

Bers D.M. et al (2009) CaMKII regulation of cardiac ion channels. J.Cardiovasc.Pharmacol. 54: 180-187