P2Y ₁₂ Promotes Migration of Vascular Smooth Muscle Cells Through Cofilin Dephosphorylation During Atherogenesis

Abstract

Objective-P2Y 12 is a well-recognized receptor expressed on platelets and the target of thienopyridine-type antiplatelet drugs. However, recent evidence suggests that P2Y 12 expressed in vessel wall plays a role in atherogenesis, but the mechanisms remain elusive. In this study, we examined the molecular mechanisms of how vessel wall P2Y 12 mediates vascular smooth muscle cells (VSMCs) migration and promotes the progression of atherosclerosis. Approach and Results-Using a high-fat diet-fed apolipoprotein E-deficient mice model, we found that the expression of P2Y 12 in VSMCs increased in a time-dependent manner and had a linear relationship with the plaque area. Moreover, administration of P2Y 12 receptor antagonist for 12 weeks caused significant reduction in atheroma and decreased the abundance of VSMCs in plaque. In cultured VSMCs, we found that activation of P2Y 12 receptor inhibited cAMP/ protein kinase A signaling pathway, which induced cofilin dephosphorylation and filamentous actin disassembly, thereby enhancing VSMCs motility and migration. In addition, the number of P2Y 12 -positive VSMCs was decreased in the carotid artery plaque from patients receiving clopidogrel. Conclusions-Vessel wall P2Y 12 receptor, which promotes VSMCs migration through cofilin dephosphorylation, plays a critical role in the development of atherosclerotic lesion and may be used as a therapeutic target for atherosclerosis. Visual Overview-An online visual overview is available for this article. VSMCs migration. In this study, we firstly investigated whether P2Y 12 inhibitor could influence the progression of atherosclerosis in vivo, and then we examined the molecular mechanisms underlying P2Y 12 -mediated VSMCs migration. Materials and MethodsMaterials and Methods are available in the online-only Data Supplement. Results P2Y 12 Receptor Antagonist Attenuates Atherosclerosis in ApoE −/− MiceTo investigate the effect of P2Y 12 receptor on atherogenesis, ApoE −/− mice were fed with high-fat diet (HFD) to induce atherogenesis. The mice were treated either with clopidogrel, which is a commonly used P2Y 12 receptor antagonist, or mannitol (vehicle) in addition to HFD for 4 or 12 weeks. Oil Red O staining showed that 4 weeks of clopidogrel treatment did not influence lesion size at either whole aorta or aortic arch when compared with vehicle. However, 12 weeks of clopidogrel treatment significantly reduced lesion area at whole aorta (12.53±1.22% versus control 20.19±1.79%; P<0.05) and aortic arch (23.07±3.10% versus control 33.05±2.18%; P<0.05; Figure 1A). Oil Red O staining at aortic root showed similar results, that compared with control vehicle, clopidogrel administration for 12 weeks significantly decreased plaque lesion, whereas clopidogrel administration for 4 weeks had no effect on plaque size ( Figure 1B). Hematoxylin and eosin staining of aortic roots also showed that clopidogrel administration for 12 weeks, but not for 4 weeks, reduced plaque area compared with vehicle administration ( Figure 1C (Figure 2A, upper). Immunoflu...

Vascular Development

“…53 In a related study, Niu et al showed that inhibition of cofilin phosphorylation via activation of the P2Y12 receptor on SMCs activate cofilin’s F-actin severing activity, increased SMC motility and migration, and promoted atherosclerosis. 54 Likewise the orphan receptor CD248/endosialin promotes SMC dedifferentiation and increases the extent of atherosclerosis in ApoE −/− mice. 55 CD248/endosialin also promotes the expression of a proinflammatory secretory phenotype in SMCs.…”

Platelet-derived microvesicles induce calcium oscillations and promote VSMC migration via TRPV4

“…The study may provide new insights into the mechanism of abnormal VSMC migration after intimal injury and may have potential clinical applications for attenuating neointimal hyperplasia after intimal injury during vascular stent surgery. Further studies are encouraged to reveal the influences and mechanisms of antiplatelet drugs, such as aspirin 73 - 75 and clopidogrel 76 , in PMV-induced calcium oscillations and in vivo regulatory functions.…”

P2Y12 Inhibition beyond Thrombosis: Effects on Inflammation

“…It is associated with increased monocyte chemoattractant protein 1 (MCP-1) expression and monocyte adhesion [54]. P2Y 12 is also implicated in the migration VSMCs through cAMP/PKA signaling pathway associated with actin disassembly and therefore an increase in VSMC motility and migration [55].…”

“…P2Y 12 is also functionally expressed in microglial cells and can play a role in their activation [16] and in microglia-neuron communications and microglial neuroprotection [56]. Thus, as microglial cells are the primary innate immune cells of the brain and play an important role in the pathophysiology of many brain-based conditions, an implication of P2Y 12 may be expected in various diseases including multiple sclerosis, Alzheimer's disease, traumatic brain and spinal cord injury, and brain cancers [55].…”