Mechanistic understanding of how Non-Alcoholic Fatty Liver disease (NAFLD) can lead to cardiovascular dysfunction using induced pluripotent stem cell (iPSC) derived cardiomyocytes and hepatocytes.

Background

Liver disease accounts for 3.5% of all global deaths/year (~2 million people) and is the third leading cause of premature death in the UK with some of the highest hospitalisations in the country seen in areas of socioeconomic deprivation. Several liver diseases are of wide clinical concern with the most prominent being NAFLD. There is no effective pharmaceutical treatment for NAFLD which now affects a third of the world’s adult population driven by epidemics of obesity and diabetes. NAFLD leads to a substantial increase in the risk of liver cancer, approximately a 17-fold increase in susceptibility. However, the leading causes of death among patients with NAFLD are cardiovascular diseases (CVD).

Aim

The pathophysiology behind the association of NAFLD with CVD and other cardiac complications is incompletely understood. We aim to understand if hepatic fat accumulation causes the release of plasma lipids and affects lipid metabolism that can contribute to cardiac damage.

Methods

Our labs have then ability to generate both liver and heart cells from induced pluripotent stem cells (iPSC) allowing us to create an in vitro model or both organ systems with the same genetic background. We will then monitor effects of lipid overload (as seen in NAFLD) on the liver cells and use conditioned media to monitor the effect on cardiomyocyte functionality. This will allow us to see if altered lipid handling releases factors or altered lipids that are detrimental to cardiac functionality. Studies have further shown that variants in PNPLA3 and TM6SF2 were found to protect against CVD, whereas variants in GCKR were positively associated with CVD. Blood cells will be reprogrammed from patients previously identified to be carrying these mutations into induced pluripotent stem cells (iPSC) using novel, integration-free Sendai-viral transduction. These will be differentiated into beating cardiomyocytes and hepatocytes that recapitulate the donor’s primary cardiomyocyte genotype and phenotype. Cells will be validated and analysed to understand the differences between these populations of patients using a multi-disciplinary approach, including evaluation of standard cell health parameters, differential protein expression by mass spectrometry and proteomics to understand pathway changes, metabolic changes via mass spectrometry-based metabolomics, and structural changes through immunofluorescence. Functional changes will be examined via standard patch-clamp electrophysiology techniques coupled with Ca²⁺-fluorescence measurements to understand ion channel and Ca²⁺ changes in the heart.

Student experience

This cutting-edge technology utilised in this studentship, coupled with world-leading equipment and facilities brings together a unique opportunity for a student to generate fundamental mechanisms and predicative tools with innovative strategies to prevent, predict and diagnose cardiovascular and liver damage.

The successful student will gain training in a multitude of techniques, ranging from 2D and 3D cell culture, iPSC generation and differentiation, electrophysiology measurements as well as specialized techniques including liquid chromatography mass spectrometry (LC/MS) using Orbitrap QExactive mass spectrometer (UoL) and proteomic analysis using tools such as Ingenuity which will be used to evaluate global changes and biomarker release upon drug administration. Validation of biomarkers and differential expressed proteins will establish skills including western blotting, immunofluorescence and ELISA.

Research Environment

The research outlined will be carried out in Department of Cardiovascular and Metabolic Medicine (CMM) at the University of Liverpool, which works synergistically with the Liverpool Centre of Cardiovascular Science (LCSS). This unique environment will allow any potential student to use clinical expertise in tandem with fundamental science to tackle a global problem. Working within this interdisciplinary centre will give the student a distinctive outlook in biomedical research and their training in novel techniques

Application is by CV and covering letter.  The covering letter must detail your interest in the studentship, related experience and training and suitability for the position.  Applications should be sent to Dr Parveen Sharma [Email Address Removed]