Reversal, Prevention of Pulmonary Fibrosis Development Possible with MicroRNA Mimic

Researchers at Yale University and miRagen Therapeutics found that when a microRNA (miRNA) mimic was injected into mice lungs, it not only blocked pulmonary fibrosis, but also reversed their symptoms within a short period of time.

Surging in prevalence, Idiopathic Pulmonary Fibrosis (IPF) currently affects over 200,000 individuals in the US. With 30,000 people dying from the condition annually, the average mortality rate after diagnosis is 3-5 years, a Yale University release mentioned.

The researchers used miR-29, a miRNA mimic that has been highlighted in previous research for its behavior with tissue fibrosis. MiRagen Therapeutics developed miR-29 intending on treating cardiac disease. However Yale researchers found it was effective for treating lung fibrosis, and believed it could do the same for pulmonary fibrosis.

“I’m particularly excited about working with this microRNA,” said van Rooij in a news release that accompanied publication of the study results. He is now at the Hubrecht Institute in the Netherlands. “All evidence points to it being a master regulator of fibrosis.”

For their study, investigators injected miR-29 into the blood of mice with bleomycin-induced pulmonary fibrosis, which was then delivered into their lung tissue. miR-29 was found to have lasting effects, both reversing and preventing pulmonary fibrosis development.

“Here, we show that intravenous injection of synthetic RNA duplexes can increase miR-29 levels in vivo for several days,” the authors reported in EMBO Molecular Medicine. “Moreover, therapeutic delivery of these miR-29 mimics during bleomycin-induced pulmonary fibrosis restores endogenous miR-29 function whereby decreasing collagen expression and blocking and reversing pulmonary fibrosis.”

Excited by their discovery, the researchers plan to explore therapeutic options for treating IPF in humans.