Work

Revisiting insulin-stimulated hydrogen peroxide dynamics reveals a cytosolic reductive shift in skeletal muscle

Year: 2025

Type: article

Abstract: The intracellular redox state is crucial for insulin responses in peripheral tissues. Despite the longstanding belief that insulin signaling increases hydrogen peroxide (H 2 O 2 ) production leading to reversible oxidation of cysteine thiols, evidence is inconsistent and rarely involves human tissues. In this study, we systematically investigated insulin-dependent changes in subcellular H 2 O 2 levels and reversible cysteine modifications across mouse and human skeletal muscle models. Utilizing advanced redox tools—including genetically encoded H 2 O 2 sensors and non-reducing immunoblotting—we consistently observed no increase in subcellular H 2 O 2 levels following insulin stimulation. Instead, stoichiometric cysteine proteome analyses revealed a selective pro-reductive shift in cysteine modifications affecting insulin transduction related proteins, including Cys179 on GSK3β and Cys416 on Ras and Rab Interactor 2 (RIN2). Our findings challenge the prevailing notion that insulin promotes H 2 O 2 generation in skeletal muscle and suggest that an insulin-stimulated pro-reductive shift modulates certain aspects of insulin signal transduction.

Source: Redox Biology

DOI: 10.1016/j.redox.2025.103607