Gentiopicroside activates PINK1-dependent mitophagy to inhibit ferroptosis and promote flap survival.

ETHNOPHARMACOLOGICAL RELEVANCE: Distal necrosis remains a major challenge in reconstructive flap surgery due to ischemia-reperfusion injury. Gentiana manshurica Kitagawa (Longdan), traditionally used to clear heat and dampness, relieve swelling and pain, and treat ischemic-inflammatory disorders, has a long history in Chinese medicine. Gentiopicroside, its bioactive component, exhibits anti-inflammatory and antioxidant activities, yet its effect on flap survival has not been fully elucidated.

AIM OF THE STUDY: This work explored whether gentiopicroside improves flap viability and elucidated the biological processes underlying its action.

MATERIALS AND

METHODS

A rat McFarlane flap model was used to evaluate flap survival, microcirculatory perfusion, histology, and protein expression. In vitro, HUVECs subjected to oxygen-glucose deprivation/reoxygenation were treated with gentiopicroside, with or without PINK1 silencing. Cellular proliferation and migration, mitochondrial integrity, oxidative stress, and key pathways related to mitophagy, ferroptosis, apoptosis, and inflammation were systematically evaluated. Bioinformatics and molecular docking analyses were performed to identify potential GPS-PINK1 interaction.

RESULTS

Gentiopicroside significantly enhanced flap survival, perfusion, angiogenesis, and endothelial cell proliferation and migration. Molecular docking confirmed strong GPS-PINK1 binding and bioinformatics linked GPS to autophagy and inflammation pathways via 28 targets. It activated PINK1-dependent mitophagy both in vivo and in vitro, alleviated oxidative stress, and suppressed ferroptosis, apoptosis, and inflammation. These protective effects were markedly attenuated by PINK1 silencing.

CONCLUSION

Gentiopicroside enhances flap survival by activating PINK1-mediated mitophagy, thereby alleviating ischemic and inflammatory tissue injury and reducing distal flap necrosis.