Fibro-Adipogenic Progenitors (FAPs) are a new class of mesenchymal Progenitors found in skeletal muscle in recent years.Under normal conditions, FAPs maintained muscle homeostasis. During muscle repair, FAPs cleared necrotic muscle fiber fragments and supported muscle stem cell regeneration. Under pathological conditions, abnormal accumulation of FAPs in muscles leads to the occurrence of fibrosis and fat infiltration.In the process of muscle regeneration, various cytokines affect the microenvironment of muscle regeneration by regulating the proliferation and differentiation of FAPs, such as TNF, TGF-β,IL-4,IL-15 and CGRP. At the same time, FAPs also secretes some cytokines to promote the regeneration of muscle stem cells, such as WISP1, Follistatin and interleukin. In addition, some signaling pathways regulate FAPs indirectly affecting skeletal muscle regeneration. This paper mainly introduced the molecular mechanism and signaling pathway of FAPs in muscle regeneration, understood the functional pathway of FAPs in muscle regeneration, and provided a strategy for the therapeutic targets of pathological regeneration such as denervation, muscular dystrophy and muscular atrophy.

Songlin Jin. The mechanism of FAPs in the regeneration of skeletal muscle. Academic Journal of Medicine & Health Sciences(2025), Vol. 6, Issue 4: 34-39. https://doi.org/10.25236/AJMHS.2025.060406.

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