Lanthionine Ketenamine Derivative Enhances Early Functional Recovery Following Skeletal Muscle Ischemia-Reperfusion...

Ischemia-reperfusion injury (IRI) induces skeletal muscle damage through oxidative stress, impaired autophagy, and satellite cell (SC) dysfunction, ultimately compromising regenerative capacity and functional recovery. We investigated whether the naturally occurring autophagy-stimulating compound 2-n-hexyl lanthionine ketenamine phosphonate (2-n-hexyl LKE-P) enhances SC resilience and promotes early regenerative responses following IRI. Primary SCs isolated from Sprague Dawley rats (96% Pax-7+ purity) were treated with 2-n-hexyl LKE-P or rapamycin. Autophagic flux was assessed using CYTO-ID flow cytometry and Western blot analysis of LC3-I and LC3-II, and viability was assessed under baseline and hydrogen peroxide (H₂O₂)-induced oxidative stress conditions. In parallel, a proof-of-concept hindlimb IRI model (3-h tourniquet) evaluated early functional recovery and transcriptional changes. In vitro, 2-n-hexyl LKE-P significantly increased autophagy flux and enhanced SC viability across concentrations and treatment durations, whereas rapamycin reduced proliferation. Under 500 µM H₂O₂, which decreased viability by ~63%, 2-n-hexyl LKE-P restored cell survival toward control levels, demonstrating robust protection against oxidative stress. In vivo, treated animals demonstrated improved grip strength recovery between days 2 and 7 post-injury compared to PBS-treated controls. Molecular analyzes revealed significant upregulation of autophagy regulators (Beclin-1, ULK-1) and antioxidant marker SOD-1, with coordinated upward trends in additional autophagy (ATG-7, LC3, p62) and myogenic genes (MyoG, MHC). Collectively, these findings suggest that 2-n-hexyl LKE-P enhances SC survival by modulating autophagy and reinforcing antioxidant defenses, resulting in improved early functional recovery following IRI. These results identify 2-n-hexyl LKE-P modulation of autophagy and oxidative stress as a promising therapeutic strategy for limiting IRI-induced skeletal muscle damage.