Abstract:
Skeletal muscle fibro-adipogenic progenitors (FAPs) have emerged as central regulators of skeletal muscle repair, orchestrating the balance between regeneration and degeneration. In this talk, I will present recent work showing how human FAP populations are functionally heterogeneous and highly responsive to the local muscle microenvironment. I will highlight evidence that specific FAP subsets promote fibrosis, fatty infiltration, and impaired regeneration in aging and metabolic disease, while others support productive tissue repair through interactions with muscle and immune cells. I will also discuss our recent findings on how FAP–macrophage communication contributes to muscle regeneration in elderly humans and how niche remodeling may shape repair outcomes. Together, these studies position FAPs not as passive bystanders, but as active directors of skeletal muscle remodeling, with important implications for understanding muscle loss and developing targeted therapies.

Bio:
Jean Farup is Associate Professor of Cellular Physiology at the Department of Biomedicine & Steno Diabetes Center Aarhus, where he leads a research group focused on skeletal muscle biology, regeneration, aging, and metabolic disease. His work centers on how the muscle microenvironment regulates tissue maintenance and repair, with particular emphasis on fibro-adipogenic progenitors and muscle stem cells. Farup has contributed important insights into muscle degeneration and impaired regeneration in aging and type 2 diabetes, using human muscle biopsies, primary cell isolation, flow cytometry, and spatial and single-cell omics.