Wang Shuai, Guo Yi, Cao Rui-Qi, Zhu Yong-Ming, Qiao Shi-Gang, Du Hua-Ping, Liu Yuan, Xu Yuan, Zhou Xian-Yong, Sun Lei, Lu Qi-Xia, Schoen Ingmar, Zhang Hui-Ling
Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology and Laboratory of Cerebrovascular Pharmacology, Suzhou Key Laboratory of Drug Research for Prevention and Treatment of Hyperlipidemic Diseases, Suzhou International Joint Laboratory for Diagnosis and Treatment of Brain Diseases, College of Pharmaceutical Science, Soochow University, Suzhou, 215123, China.
Irish Centre for Vascular Biology, School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland RCSI, Dublin, Ireland.
Acta Pharmacol Sin. 2025 Feb;46(2):292-307. doi: 10.1038/s41401-024-01405-6. Epub 2024 Oct 30.
Astrocyte-derived IL-3 activates the corresponding receptor IL-3Rα in microglia. This cross-talk between astrocytes and microglia ameliorates the pathology of Alzheimer's disease in mice. In this study we investigated the role of IL-3/IL-3Rα cross-talk and its regulatory mechanisms in ischemic stroke. Ischemic stroke was induced in mice by intraluminal occlusion of the right middle cerebral artery (MCA) for 60 min followed by reperfusion (I/R). Human astrocytes or microglia subjected to oxygen-glucose deprivation and reoxygenation (OGD/Re) were used as in vitro models of brain ischemia. We showed that both I/R and OGD/Re significantly induced decreases in astrocytic IL-3 and microglial IL-3Rα protein levels, accompanied by pro-inflammatory activation of A1-type astrocytes and M1-type microglia. Importantly, astrocyte-derived VEGFD acting on VEGFR3 of astrocytes and microglia contributed to the cross-talk dysfunction and pro-inflammatory activation of the two glial cells, thereby mediating neuronal cell damage. By using metabolomics and multiple biochemical approaches, we demonstrated that IL-3 supplementation to microglia reversed OGD/Re-induced lipid metabolic reprogramming evidenced by upregulated expression of CPT1A, a rate-limiting enzyme for the mitochondrial β-oxidation, and increased levels of glycerophospholipids, the major components of cellular membranes, causing reduced accumulation of lipid droplets, thus reduced pro-inflammatory activation and necrosis, as well as increased phagocytosis of microglia. Notably, exogenous IL-3 and the VEGFR antagonist axitinib reestablished the cross-talk of IL-3/IL-3Rα, improving microglial lipid metabolic levels via upregulation of CPT1A, restoring microglial phagocytotic function and attenuating microglial pro-inflammatory activation, ultimately contributing to brain recovery from I/R insult. Our results demonstrate that VEGFD/VEGFR3 signaling contributes to the dysfunction of the astrocyte IL-3/microglia IL-3Rα cross-talk and drives pro-inflammatory activation, causing lipid metabolic reprogramming of microglia. These insights suggest VEGFR3 antagonism or restoring IL-3 levels as a potential therapeutic strategy for ischemic stroke.
星形胶质细胞衍生的白细胞介素-3（IL-3）激活小胶质细胞中相应的受体IL-3Rα。星形胶质细胞与小胶质细胞之间的这种相互作用改善了小鼠阿尔茨海默病的病理状况。在本研究中，我们调查了IL-3/IL-3Rα相互作用在缺血性中风中的作用及其调控机制。通过右侧大脑中动脉（MCA）腔内闭塞60分钟后再灌注（I/R）诱导小鼠发生缺血性中风。将经历氧-葡萄糖剥夺和复氧（OGD/Re）的人星形胶质细胞或小胶质细胞用作脑缺血的体外模型。我们发现，I/R和OGD/Re均显著诱导星形胶质细胞IL-3和小胶质细胞IL-3Rα蛋白水平降低，同时伴有A1型星形胶质细胞和M1型小胶质细胞的促炎激活。重要的是，星形胶质细胞衍生的血管内皮生长因子D（VEGFD）作用于星形胶质细胞和小胶质细胞的血管内皮生长因子受体3（VEGFR3），导致这两种神经胶质细胞的相互作用功能障碍和促炎激活，从而介导神经元细胞损伤。通过代谢组学和多种生化方法，我们证明向小胶质细胞补充IL-3可逆转OGD/Re诱导的脂质代谢重编程，这表现为肉碱棕榈酰转移酶1A（CPT1A，线粒体β氧化的限速酶）表达上调，以及细胞膜主要成分甘油磷脂水平升高，导致脂滴积累减少，从而减少促炎激活和坏死，以及增加小胶质细胞的吞噬作用。值得注意的是，外源性IL-3和VEGFR拮抗剂阿昔替尼重新建立了IL-3/IL-3Rα的相互作用，通过上调CPT1A改善小胶质细胞脂质代谢水平，恢复小胶质细胞吞噬功能并减弱小胶质细胞促炎激活，最终有助于从I/R损伤中恢复大脑功能。我们的结果表明，VEGFD/VEGFR3信号传导导致星形胶质细胞IL-3/小胶质细胞IL-3Rα相互作用功能障碍，并驱动促炎激活，引起小胶质细胞脂质代谢重编程。这些见解表明，拮抗VEGFR3或恢复IL-3水平作为缺血性中风的潜在治疗策略。
