Leu promotes C2C12 cell differentiation by regulating the GSK3β/β‐catenin signaling pathway through facilitating the interaction between SESN2 and RPN2

Abstract

BackgroundLeucine (Leu), an essential amino acid that facilitated skeletal muscle satellite cell differentiation, yet its mechanism remained underexplored. Sestrin2 (SESN2) served as a Leu sensor, binding directly to Leu, while Riboprotein II (RPN2) acted as a signaling factor in multiple pathways. This study aimed to elucidate Leu's impact on mouse C2C12 cell differentiation and skeletal muscle injury repair by modulating RPN2 expression through SESN2, offering a theoretical foundation for clinical skeletal muscle injury prevention and treatment.ResultsLeu addition promoted C2C12 cell differentiation compared to the control, enhancing early differentiation via MYOD up‐regulation. Sequencing revealed SESN2 binding to and interacting with RPN2. RPN2 overexpression up‐regulated MYOD, MYOG, and MYH2, concurrently decreased p‐GSK3β, and increased nuclear β‐catenin. Conversely, RPN2 knockdown yielded opposite results. Combining RPN2 knockdown with Leu rescued increased p‐GSK3β and decreased nuclear β‐catenin compared to Leu absence. HE staining results showed that Leu addition accelerated mouse muscle damage repair, up‐regulating Pax7, MYOD, and RPN2 in the cytoplasm, and nuclear β‐catenin, confirmed that the role of Leu's in muscle injury repair was consistent with the results in C2C12 cell.ConclusionLeu, bound with SESN2, up‐regulated RPN2 expression, activated the GSK3β/β‐catenin pathway, enhanced C2C12 differentiation, and expedited skeletal muscle damage repair.This article is protected by copyright. All rights reserved.