Wang Chaoqun, Li Yuntao, Zhang Yonggang, Smerin Daniel, Gu Lijuan, Jiang Shuting, Xiong Xiaoxing
Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan, China.
Central Laboratory, Renmin Hospital of Wuhan University, Wuhan, China.
Mol Med. 2024 Dec 6;30(1):242. doi: 10.1186/s10020-024-00995-5.
Triolein, a symmetric triglyceride exhibiting anti-inflammatory and antioxidant properties, has demonstrated potential in mitigating cellular damage. However, its therapeutic efficacy in ischemic stroke (IS) and underlying molecular mechanisms remain elusive. Given the critical roles of inflammation and autophagy in IS pathogenesis, this study aimed to elucidate the effects of triolein in IS and investigate its mechanism of action.
We evaluated the impact of triolein using both in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) and in vivo middle cerebral artery occlusion (MCAO/R) models. Neurological function and cerebral infarct volume were assessed 72 h post-reperfusion. Autophagy was quantified through monodansyl cadaverine (MDC) labeling of autophagic vesicles and Western blot analysis of autophagy-related proteins. Microglial activation was visualized via immunofluorescence, while inflammatory cytokine expression was quantified using RT-qPCR. The cytoprotective effect of triolein on OGD/R-induced HT22 cells was evaluated using Cell Counting Kit-8 and lactate dehydrogenase release assays. The involvement of the Protein kinase B/Mechanistic target of rapamycin kinase (AKT/mTOR) pathway was assessed through Western blot analysis.
Triolein administration significantly reduced infarct volume, enhanced neurological recovery, and attenuated M1 microglial activation and inflammation in MCAO/R-induced mice. Western blot analysis and MDC labeling revealed that triolein exerted an inhibitory effect on post-IS autophagy. Notably, in the BV2-induced OGD/R model, triolein demonstrated an autophagy-dependent suppression of the inflammatory response. Furthermore, triolein inhibited the activation of the AKT/mTOR signaling pathway, consequently attenuating autophagy and mitigating the post-IS inflammatory response.
This study provides novel evidence that triolein exerts neuroprotective effects by inhibiting post-stroke inflammation through an autophagy-dependent mechanism. Moreover, the modulation of the AKT/mTOR signaling pathway appears to be integral to the neuroprotective efficacy of triolein. These findings elucidate potential therapeutic strategies for IS management and warrant further investigation.
三油酸甘油酯是一种具有抗炎和抗氧化特性的对称甘油三酯，已显示出减轻细胞损伤的潜力。然而，其在缺血性中风（IS）中的治疗效果及潜在分子机制仍不清楚。鉴于炎症和自噬在IS发病机制中的关键作用，本研究旨在阐明三油酸甘油酯在IS中的作用，并探究其作用机制。
我们使用体外氧糖剥夺/复氧（OGD/R）和体内大脑中动脉闭塞（MCAO/R）模型评估了三油酸甘油酯的影响。在再灌注72小时后评估神经功能和脑梗死体积。通过单丹磺酰尸胺（MDC）标记自噬小泡和对自噬相关蛋白进行蛋白质印迹分析来定量自噬。通过免疫荧光观察小胶质细胞活化，同时使用RT-qPCR定量炎症细胞因子表达。使用细胞计数试剂盒-8和乳酸脱氢酶释放试验评估三油酸甘油酯对OGD/R诱导的HT22细胞的细胞保护作用。通过蛋白质印迹分析评估蛋白激酶B/雷帕霉素激酶机制性靶点（AKT/mTOR）通路的参与情况。
给予三油酸甘油酯可显著减少MCAO/R诱导的小鼠的梗死体积，促进神经功能恢复，并减轻M1小胶质细胞活化和炎症。蛋白质印迹分析和MDC标记显示，三油酸甘油酯对IS后的自噬有抑制作用。值得注意的是，在BV2诱导的OGD/R模型中，三油酸甘油酯表现出对炎症反应的自噬依赖性抑制。此外，三油酸甘油酯抑制AKT/mTOR信号通路的激活，从而减弱自噬并减轻IS后的炎症反应。
本研究提供了新的证据，表明三油酸甘油酯通过自噬依赖性机制抑制中风后炎症发挥神经保护作用。此外，AKT/mTOR信号通路的调节似乎是三油酸甘油酯神经保护作用的关键。这些发现阐明了IS治疗的潜在策略，值得进一步研究。
