Calycosin alleviates ischemia-reperfusion-induced microvascular injury through improving endothelial dysfunction and promoting angiogenesis by targeting ERBB2 signaling

Although calycosin has been shown to exert protective effects against ischemia-reperfusion injury, whether it also attenuates the associated microvascular injury remains to be determined. This study aimed to investigate the mechanism of Calycosin on microvascular dysfunction, and angiogenesis in ischemia-reperfusion-induced microvascular injury. Network pharmacology identified Calycosin from an herbal source as a candidate, with ERBB2 predicted as its target, and subsequent in vitro and in vivo validations were conducted. Molecular docking and drug affinity responsive target stability assay confirmed direct binding of Calycosin to ERBB2. In a male Sprague-Dawley rat ischemia-reperfusion-induced microvascular injury model, Calycosin dose-dependently reduced myocardial Evans blue leakage, restored microvascular ultrastructure, increased myocardial CD34+ microvessel density, and preserved cardiac function. These changes were accompanied by decreased serum TNF-α, IL-1β, and IL-18, upregulated myocardial ZO-1, Occludin, Claudin-5, VE-cadherin, eNOS, NO, and VEGF, and reduced myocardial apoptosis. In OGD/R-stressed HUVECs, Calycosin reduced apoptosis and permeability, inhibited inflammatory factor release, and promoted migration, invasion, and tube formation. Calycosin suppressed ERBB2 signaling and the phosphorylation of ERBB3, and PTEN and MYC expression. ERBB2 overexpression reversed Calycosin effects on endothelial permeability, inflammation, and angiogenesis. These results demonstrate that Calycosin targets ERBB2 signaling to improve microvascular integrity, suppress inflammation, and promote angiogenesis in ischemia-reperfusion-induced microvascular injury. Our findings may provide new strategies for the clinical treatment of ischemia-reperfusion-induced microvascular injury.