Abstract

3,5-DCQA alleviates ISS by targeting ferroptosis. • 3,5-DCQA binds with high affinity to GPX4, restoring redox homeostasis and inhibiting lipid peroxidation. • In pMCAO rats, 3,5-DCQA improves muscle mass, strength, and motor performance via GPX4 activation. • Loss and gain of function assays confirm that the anti-ISS effects of 3,5-DCQA are GPX4-dependent. • This study identifies 3,5-DCQA as a novel anti-ferroptotic candidate for post-stroke muscle degeneration therapy. Background Ischemic stroke-induced sarcopenia (ISS) is a major contributor to poststroke motor dysfunction and severely impairs quality of life. Ferroptosis, an iron- and lipid peroxidation- dependent form of programmed cell death, has not been fully explored in ISS. Purpose To evaluate the natural compound 3,5-dicaffeoylquinic acid (3,5-DCQA) as a novel anti-ferroptosis agent that markedly attenuates ISS via glutathione peroxidase 4 (GPX4)-mediated ferroptosis inhibition. Methods A permanent middle cerebral artery occlusion (pMCAO) rat model was established. Cerebral injury was assessed using laser speckle contrast imaging and Zea-Longa neurological scoring. The effect of 3,5-DCQA on muscle function was evaluated through behavioral analyses and histopathological staining. Molecular interactions were validated by combining GPX4 silencing via siRNA in L6 and HSkMC cells with RNA-seq and surface plasmon resonance (SPR). The involvement of the ferroptosis signaling pathway in ISS was examined using flow cytometry, immunofluorescence (IF), immunohistochemistry (IHC), and Western blotting (WB). Results 3,5-DCQA markedly improved muscle mass, strength, and motor performance. Mechanistically, it reduced ferrous iron and lipid peroxidation products, including malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), and lipid peroxides, and downregulated muscle atrophy factors, muscle RING-finger protein-1 (MuRF1) and muscle atrophy F-box (MAFbx). In vitro , 3,5-DCQA decreased reactive oxygen species (ROS) and fe