Temporal Proteomic Profiling Reveals Tissue-Specific and Coordinated Metabolic Reprogramming in Skeletal Muscle and...

Fasting triggers profound systemic metabolic adaptations that are essential for survival during nutrient scarcity, yet the temporal dynamics and cross-tissue coordination of proteomic remodeling remain incompletely characterized. Here, we employed quantitative proteomics to systematically profile the gastrocnemius (GA) muscle and liver of mice subjected to a 72 h fasting challenge at five time points (0, 12, 24, 48, and 72 h). Principal component analysis and hierarchical clustering revealed progressive, time-dependent proteomic reprogramming in both tissues, with distinct temporal trajectories of differentially expressed proteins (DEPs). GA muscle exhibited a biphasic response, with maximal downregulation at 48 h and peak upregulation at 72 h, whereas liver displayed a monotonic increase in DEPs, predominantly characterized by suppression of anabolic programs. Integrative cross-tissue analysis identified 97 conserved fasting-responsive proteins, including molecular chaperones (HSPA5, HSP90B1), complement components (C3), and coagulation factors (FGA, KNG1), which formed highly interconnected protein-protein interaction hubs. Fuzzy c-means clustering resolved five major temporal expression modules in each tissue, revealing coordinated shifts in mitochondrial metabolism, proteostasis, translation, and stress-response pathways. Spearman correlation analysis demonstrated moderate yet stable cross-tissue concordance (r = 0.43-0.48) throughout fasting, suggesting shared systemic regulatory mechanisms. Collectively, our findings provide a comprehensive temporal atlas of fasting-induced proteomic remodeling, revealing tissue-specific adaptive strategies alongside conserved molecular programs that orchestrate multi-organ metabolic homeostasis during prolonged nutrient deprivation.