Development of RNA therapeutics for cardiac regeneration

Abstract

Neonatal mammals have the remarkable ability to regenerate their heart after injury, however 1-week after birth this regenerative ability is lost. This change in regenerative potential coincides with dramatic physiological changes including changes in mechanical work, sarcomere maturation and metabolic alterations. This thesis seeks to identify sarcomeric, cytoskeletal and metabolic proteins responsible for controlling cardiomyocyte proliferation using a high-throughput siRNA screening in primary neonatal mouse cardiomyocytes. From this list of proliferative siRNAs, mechanistic studies identify YAP and alterations in the Hippo pathway as central players in mediating the identified hits’ proliferative effect. In addition to investigating fundamental questions of cardiomyocyte biology, this thesis also seeks to develop lipid nanoparticles to deliver exogenous RNAs for the purpose of cardiac regeneration. Lipid nanoparticles underwent substantial in vitro optimisation using a design of experiments approach. To improve development, particles were also optimised using EGFP mRNA to visualise particle efficacy. This optimisation methodology eventually led to the development of J4, a lipid nanoparticle containing microRNA-1825. When administered in vivo after myocardial infarction, J4 increased cardiomyocyte proliferation and improved functional cardiac parameters after myocardial infarction.

Date of Award	1 Nov 2024
Original language	English
Awarding Institution	King's College London
Supervisor	Mauro Giacca (Supervisor) & Ajay Shah (Supervisor)