Studies of Lipid Metabolism in Skeletal Muscle Hypertrophy

(JSNFS Award for Young Investigators (2023))

Abstract

Skeletal muscle plays an important role in glucose metabolism, and is associated with several metabolic disorders such as type 2 diabetes mellitus. Excess lipid accumulation in skeletal muscle is known to be involved in insulin resistance in patients with type 2 diabetes, and lipid is thought to play an important role in muscle function. However, lipid analysis of skeletal muscle is very difficult because of the heterogeneity of fast-twitch and slow-twitch fibers, which differ in their lipid metabolism. Using mass spectrometry imaging, I investigated the localization of lipids in skeletal muscle sections at the level of molecular species. This revealed that fast-twitch and slow-twitch fibers differ in their constituent cell membrane phospholipids, and that these phospholipids can change when muscle hypertrophy occurs.