Recent studies have shown that TRPA1, a nonselective cation channel with high permeability to calcium, is expressed in many tissues of the cardiovascular system and is involved in the pathogenesis of many cardiovascular diseases. However, the role of TRPA1 in cardiac repair after myocardial infarction (MI) has not been clearly defined. The aim of this study was to confirm whether inhibition of TRPA1 could attenuate MI-induced cardiac ischemia injury. The C57BL/6 mice were subjected to ligation of the left anterior descending coronary artery and treated with TRPA1-specific inhibitor HC-030031 (HC) for 4 weeks. Echocardiography was performed to assess cardiac function. The results showed that HC significantly attenuated MI-induced cardiac dysfunction 4 weeks after MI. Similarly, HC reduced cardiac fibrosis and cell apoptosis after MI and significantly increased angiogenesis in the border zone of the infarct. In vitro, we found that HC promoted the proliferation and migration of human umbilical vein endothelial cells (HUVECs). Importantly, HC treatment decreased phosphatase and tensin homolog expression and augmented the expression of phosphorylated Akt in the myocardium post MI and HUVECs. However, treatment of HUVECs with a PI3K inhibitor, LY294002, before HC administration almost completely abolished HC-induced migration in HUVECs. In conclusion, we demonstrate that the inhibition of TRPA1 promotes angiogenesis after MI, thereby alleviating myocardial ischemia injury via mechanisms involving inhibition of phosphatase and tensin homolog expression and subsequent activation of the PI3K/Akt signaling.

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Vascular inflammation is a key factor in the pathogenesis of atherosclerosis. Salidroside is an important active ingredient extracted from the root of the Rhodiola rosea plant, which has been reported to have antioxidative, anti-cancer, neuroprotective and cardioprotective effects. However, the effects of salidroside on vascular inflammation have not been clarified. The purpose of the present study was to investigate the protective effects of salidroside against tumor necrosis factor (TNF)-α-induced vascular inflammation in cardiac microvascular endothelial cells (CMECs), a specific cell type derived from coronary micro-vessels. Over a 24-h period, salidroside did not exert any significant cytotoxicity up to a dose of 100 µM. Additionally, salidroside decreased the expression levels of the cell adhesion molecule vascular cell adhesion molecule-1 (VCAM-1) in TNF-α-stimulated CMECs, thus suppressing monocyte-to-CMEC adhesion. Salidroside also decreased the production of inflammatory cytokines such as interleukin (IL)-1β, IL-6 and monocyte chemotactic protein 1 (MCP-1) in TNF-α-induced CMECs, as well as suppressing TNF-α-activated mitogen-activated protein kinase (MAPK) and NF-κB activation. Since MAPKs and NF-κB both serve notable roles in regulating the expression of VCAM-1, IL-1β, IL-6 and MCP-1, the present study provided a preliminary understanding of the mechanism underlying the protective effects of salidroside. Overall, salidroside alleviated vascular inflammation by mediating MAPK and NF-κB activation in TNF-α-induced CMECs. These results indicated that salidroside may have potential applications as a therapeutic agent against vascular inflammation and atherosclerosis.