Novel biomaterial utilizes microRNAs for bone regeneration

Written by Harriet Wall

Colorized scanning electron micrograph shows bone cells attaching to a new type of bone cement made of calcium phosphate.

Scientists from the Royal College of Surgeons in Ireland (RCSI) University of Medicine and Health Sciences (Dublin, Ireland) have recently developed a novel biomaterial which mediates microRNAs, small non-coding molecules that play an important role in gene regulation, for the acceleration of bone regeneration.

The inhibition of a specific microRNA, miR-133a, is thought to enhance bone repair. For this reason, the team developed a nanoparticle and collagen-based scaffold that could be surgically implanted into the target site to aid the delivery of antagomiR-133a, a microRNA silencer.

Their study, published in Acta Biomaterialia, showed that the localized delivery of antagomiR-133a increased bone volume by 10-fold in rats compared with an empty deficit control.

“The results of our research are a promising step towards improving health outcomes for patients with fractures that fail to repair naturally or have degenerative bone diseases such as osteoporosis, although further pre-clinical and clinical trials are still required before the technology could be used to treat humans,” commented Caroline Curtin, Lecturer in Anatomy and Regenerative Medicine at RCSI.

The method also promoted a pro-repair immune system response, which decreased the risk of inflammation and other complications.

“We are confident that this biomaterial system will have several potential applications beyond bone repair, as it can be tailored to deliver other therapeutic molecules that address degenerated or diseased tissue in the body. At RCSI Tissue Engineering Research Group, we are exploring these possibilities through the development of similar methods to repair articular joints like the knee and hip, and attempting to apply the microRNA delivery systems to inhibit breast cancer cell growth and other novel research,” commented Fergal O’Brien, RCSI Director of Research and Innovation, Professor of Bioengineering and Regenerative Medicine and Deputy Director of the SFI AMBER Centre.

This novel delivery platform offers an exciting possibility for a variety of therapeutic uses.

Sources: Castaño IM, Raftery RM, Chen G. Rapid Bone Repair With the Recruitment of CD206 + M2-like Macrophages Using Non-Viral Scaffold-Mediated miR-133a Inhibition of Host Cells. Acta Biomater. 109 (267-279) (2020);