In a global first, researchers at the Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM) have discovered a specific microRNA that protects small blood vessels and supports kidney function following severe injury. This breakthrough could revolutionize early diagnosis and prevention for more than four million Canadians living with chronic renal failure—and millions more worldwide.
miR-423-5p: A Promising Biomarker for Kidney Health
The study, recently published in JCI Insight, highlights miR-423-5p as a blood-based biomarker capable of predicting the health of kidney microvasculature. Until now, clinicians lacked reliable tools to assess the status of these tiny blood vessels, which play a critical role in filtering waste and maintaining kidney function.
Medical professors Marie-Josée Hébert and Héloïse Cardinal, co-holders of the Shire Chair in Nephrology, Renal Transplantation, and Regeneration at Université de Montréal, co-authored the research with Hébert’s associate, Francis Migneault. Their team specializes in studying the loss of peritubular capillaries—an early warning sign of chronic kidney failure.
Blood Flow Disruptions Threaten Kidney Survival
Kidney injuries often result from temporary blood flow interruptions, such as those during surgeries or transplants. These disruptions can destroy small blood vessels, severely impacting kidney performance.
“In transplant patients, if kidney function deteriorates significantly, the organ’s survival is jeopardized,” explained Hébert, a nephrologist and former vice-rector for research at UdeM. “By detecting the miR-423-5p marker early, physicians could assess vascular health much sooner and intervene appropriately.”
This would be particularly valuable for high-risk individuals, including elderly patients or those undergoing cardiovascular procedures involving blood flow stoppage.
From Mice Models to Human Validation
The research team first noticed variable levels of miR-423-5p in mice with acute kidney injuries. They then validated their findings in 51 human transplant recipients using samples from the CHUM kidney transplant biobank.
“Remarkably, when we injected this microRNA into injured mice, we preserved their kidney microvasculature and reduced overall damage,” said Migneault, the study’s lead author.
Next Steps: Expanding Delivery Methods
While injecting the microRNA directly into the kidney is viable during transplant surgery, scientists are now exploring alternative delivery techniques. These may include microRNA cocktails or other systemic transport methods to target kidney tissues more broadly.
Wider Applications Beyond Kidney Disease
As reported by medicalxpress, the implications extend beyond nephrology. According to Hébert, miR-423-5p could aid in the prevention and management of cardiac failure, pulmonary disease, and even neurodegenerative conditions—ailments in which the loss of microvessels is strongly linked to aging.
“Our discovery could significantly impact Canadians’ health by offering earlier interventions across a range of chronic diseases,” she added.
Ongoing Research and Broader Clinical Utility
Several parallel studies are underway, including investigations into pulmonary failure led by Emmanuelle Brochiero, head of the Immunopathology research theme at CRCHUM. Additionally, researchers plan to evaluate whether medications given post-transplant inadvertently affect microvascular health, using CHUM’s extensive biobank resources.
This milestone discovery opens the door to developing targeted therapies and early diagnostic tools—ushering in a new era of personalized care for patients at risk of kidney and vascular complications.