Intravenous and oral administration of the synthetic RNA drug, TY1, reverses heart failure with preserved ejection fraction in mice.

TY1, a synthetic non-coding RNA (ncRNA) bioinspired by small Y RNAs abundant in extracellular vesicles (EVs), decreases cGAS/STING activation in myocardial infarction and thereby attenuates inflammation. Motivated by the concept that heart failure with preserved ejection fraction (HFpEF) is a systemic inflammatory disease, we tested TY1 in a murine model of HFpEF. Intravenous TY1, packaged in a transfection reagent, reversed the cardiac and systemic manifestations of HFpEF in two-hit obese-hypertensive mice, without inducing weight loss.

Augmentation of DNA exonuclease TREX1 in macrophages as a therapy for cardiac ischemic injury.

Unlabelled: Noncoding RNAs (ncRNAs) are increasingly recognized as bioactive. Here we report the development of TY1, a synthetic ncRNA bioinspired by a naturally-occurring human small Y RNA with immunomodulatory properties. TY1 upregulates TREX1, an exonuclease that rapidly degrades cytosolic DNA.

Small molecule inhibitors and culture conditions enhance therapeutic cell and EV potency via activation of beta-catenin and suppression of THY1.

Primary cell therapy continues to face significant hurdles to therapeutic translation including the inherent variations that exist from donor to donor, batch to batch, and scale-up driven modifications to the manufacturing process. Cardiosphere-derived cells (CDCs) are stromal/progenitor cells with clinically demonstrated tissue reparative capabilities. Mechanistic investigations have identified canonical Wnt/β-catenin signaling as a therapeutic potency marker, and THY1 (CD90) expression as inversely correlated with potency.

A comprehensive method for identification of suitable reference genes in extracellular vesicles.

Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is one of the most sensitive, economical and widely used methods for evaluating gene expression. However, the utility of this method continues to be undermined by a number of challenges including normalization using appropriate reference genes. The need to develop tailored and effective strategies is further underscored by the burgeoning field of extracellular vesicle (EV) biology.

Exosomes as critical agents of cardiac regeneration triggered by cell therapy.

The CADUCEUS trial of cardiosphere-derived cells (CDCs) has shown that it may be possible to regenerate injured heart muscle previously thought to be permanently scarred. The mechanisms of benefit are known to be indirect, but the mediators have yet to be identified. Here we pinpoint exosomes secreted by human CDCs as critical agents of regeneration and cardioprotection.