Fall 2025 Grantee Highlight:
Ronald M. Evans

Ronald M. Evans, PhD

Professor and Director of Gene Expression Laboratory, The Salk Institute for Biological Studies

Skeletal muscle is the largest organ in the human body and is fundamental to mobility, metabolic health, and physical well-being. Many people with obesity already experience significant muscle loss, a growing but underrecognized complication that currently affects over 30 million Americans. This problem is further exacerbated by the rise of GLP‑1–based weight‑loss drugs, which effectively reduce body weight but often induce significant muscle wasting for which no targeted treatments exist.

The Evans Lab studies how the gene p21 drives senescence—a chronic, damage‑prone state linked to aging—in muscle fibers. This work aims to pave the way for therapies that protect muscle mass during obesity and weight‑loss treatments. Their research has identified that p21 becomes abnormally activated in muscle fibers during both obesity and weight loss. Even though mature muscle fibers do not divide, p21 can push them into harmful senescence, leading to structural deterioration and chronic inflammation. By using advanced genetic tools and novel p21‑suppressing drugs, the team aims to block this pathway and preserve muscle strength for those affected by obesity, aging, and chronic illness.