Developmental overlap between skeletal muscle maturation and perirenal fat brown-to-white transition in goats: Exploring the role of Myf-5

Biochimie. 2024 Aug 7:S0300-9084(24)00191-3. doi: 10.1016/j.biochi.2024.08.005. Online ahead of print.

Abstract

In mammals, skeletal muscles (SkMs) and adipose tissues regulate energy homeostasis and share developmental origins. Notably, the perirenal adipose tissue (PRAT) depot has been reported to display adipocyte heterogeneity: while some originated from Myogenic factor 5 (Myf-5) expressing progenitors, others did not. Our study examines the expression and distribution of Myf-5 using immunohistochemical staining and western blotting of PRAT, gastrocnemius, and trapezius from goat at various developmental stages. Contrary to earlier beliefs, functionally divergent SkM gastrocnemius and trapezius showed similar Myf-5 expressional pattern. SkM abundantly expresses Myf-5 in developing myocytes which gradually becomes limited to the nucleus of myogenic stem cells and is retained only in a few differentiated postnatal fibers. During the same period, PRAT displays a unique brown-to-white transition. PRAT exhibited an elevated expression of Myf-5 during prenatal periods, which declines thereafter and becomes negligible during adulthood where it gets fully enriched white adipocytes. The reduction of Myf-5 during the neonatal period was common to all three tissues. However, Myf-5 expression was retained in some of the differentiated myofibers while it was undetectable in adult PRAT. These observations suggest a possible developmental interplay between adipose tissue and SkM where Myf-5 might be a major regulator.

Keywords: Adipose tissue; Development; Myf-5; Myogenesis; Skeletal muscle.