Research conducted by an international team led by biologists at the University of Kentucky has found that the ability to regenerate complex tissue may be more widespread in mammals than previously thought. This study represents an important step towards understanding why most mammals, particularly humans, have limited regenerative abilities. Basic research studies like this hold promise for developing novel regenerative therapies in humans.
Vertebrate regeneration is most commonly found in reptiles, amphibians, and fish. In mammals, it is usually limited, as seen in deer regrowing antlers or mice regrowing lost digit tips.
The latest study builds upon previous work using spiny mice by Ashley W. Seifert, Ph.D., a professor in the Department of Biology at the UK College of Arts and Sciences. These rodents are known for their unique ability to regrow lost skin, restore function to a severed spinal cord, and repair damaged heart tissue.
The paper titled "Complex tissue regeneration in Lophuromys reveals a phylogenetic signal for enhanced regenerative ability in deomyine rodents" was published in the Proceedings of the National Academy of Sciences of the United States of America (PNAS).
The study focused on a group of African rodents called brush-furred mice (Lophuromys), which were found to regrow musculoskeletal tissue instead of healing injuries with scar tissue. Seifert and the research team examined ear injuries in various rodent species found in Kenya and studied non-murid rodents for comparison.
Seifert stated, "This project establishes an evolutionary framework to study complex tissue regeneration in mammals. Our study found that only spiny mice and brush-furred mice could regenerate complete tissue." He added that the discovery provides a phylogenetic signal for enhanced regenerative ability, suggesting that specific features in their common ancestor facilitated regeneration.
Ph.D. student Brennan Riddell emphasized the importance of understanding regeneration, stating, "Discovering a unique instance of regeneration in a poorly characterized mammalian lineage should encourage curiosity and protection of our biodiversity."
The collaboration between the University of Kentucky and the University of Nairobi contributed to discovering mammals capable of healing through regeneration. Stephen Kiama, Ph.D., vice-chancellor of the University of Nairobi, noted this study provides another model for scar-free wound healing.
The research team aims to understand complex tissue regeneration in mammals, particularly rodents, and recognizes the potential for future discoveries. Adam Ferguson, Ph.D., collection manager at the Field Museum of Natural History, remarked, "Documenting musculoskeletal regeneration in brush-furred mice gets us one step closer to understanding the shared evolutionary history of this unique lineage of rodents."
Molly McDonough, Ph.D., an assistant professor at Chicago State University, stressed the importance of comparative studies across multiple species to understand the diversity of regenerative abilities and their evolution. Riddell stated, "Future work can use this multi-species system to study the mechanisms underlying mammalian regeneration."
Seifert concluded, "This study provides the foundation to test the degree to which specific cellular, genetic, and physiological features correlate with regenerative ability, paving the way for subsequent studies." The research holds promise for developing new therapies for wound healing, tissue repair, and organ regeneration.