PDF(Pubmed)
Abstract：
UNASSIGNED: Aging increases the risk of atherosclerotic vascular disease and its complications. Macrophages are pivotal in the pathogenesis of vascular aging, driving inflammation and atherosclerosis progression. NOX4 (NADPH oxidase 4) expression increases with age, correlating with mitochondrial dysfunction, inflammation, and atherosclerosis. We hypothesized that the NOX4-dependent mitochondrial oxidative stress promotes aging-associated atherosclerosis progression by causing metabolic dysfunction and inflammatory phenotype switch in macrophages.
UNASSIGNED: We studied atherosclerotic lesion morphology and macrophage phenotype in young (5-month-old) and aged (16-month-old) Nox4 -/-/Apoe -/- and Apoe -/- mice fed Western diet.
UNASSIGNED: Young Nox4-/-/Apoe-/- and Apoe-/- mice had comparable aortic and brachiocephalic artery atherosclerotic lesion cross-sectional areas. Aged mice showed significantly increased lesion area compared with young mice. Aged Nox4-/-/Apoe-/- had significantly lower lesion areas than Apoe-/- mice. Compared with Apoe-/- mice, atherosclerotic lesions in aged Nox4-/-/Apoe-/- showed reduced cellular and mitochondrial ROS and oxidative DNA damage, lower necrotic core area, higher collagen content, and decreased inflammatory cytokine expression. Immunofluorescence and flow cytometry analysis revealed that aged Apoe-/- mice had a higher percentage of classically activated pro-inflammatory macrophages (CD38+CD80+) in the lesions. Aged Nox4-/-/Apoe-/- mice had a significantly higher proportion of alternatively activated pro-resolving macrophages (EGR2+/CD163+CD206+) in the lesions, with an increased CD38+/EGR2+ cell ratio compared with Apoe-/- mice. Mitochondrial respiration assessment revealed impaired oxidative phosphorylation and increased glycolytic ATP production in macrophages from aged Apoe-/- mice. In contrast, macrophages from Nox4-/-/Apoe-/- mice were less glycolytic and more aerobic, with preserved basal and maximal respiration and mitochondrial ATP production. Macrophages from Nox4-/-/Apoe-/- mice also had lower mitochondrial ROS levels and reduced IL1β secretion; flow cytometry analysis showed fewer CD38+ cells after IFNγ+LPS treatment and more EGR2+ cells after IL4 treatment than in Apoe-/- macrophages. In aged Apoe-/- mice, inhibition of NOX4 activity using GKT137831 significantly reduced macrophage mitochondrial ROS and improved mitochondrial function, resulting in decreased CD68+CD80+ and increased CD163+CD206+ lesion macrophage proportion and attenuated atherosclerosis.
UNASSIGNED: Our findings suggest that increased NOX4 in aging drives macrophage mitochondrial dysfunction, glycolytic metabolic switch, and pro-inflammatory phenotype, advancing atherosclerosis. Inhibiting NOX4 or mitochondrial dysfunction could alleviate vascular inflammation and atherosclerosis, preserving plaque integrity.
UNASSIGNED: We studied atherosclerotic lesion morphology and macrophage phenotype in young (5-month-old) and aged (16-month-old) Nox4 -/-/Apoe -/- and Apoe -/- mice fed Western diet.
UNASSIGNED: Young Nox4-/-/Apoe-/- and Apoe-/- mice had comparable aortic and brachiocephalic artery atherosclerotic lesion cross-sectional areas. Aged mice showed significantly increased lesion area compared with young mice. Aged Nox4-/-/Apoe-/- had significantly lower lesion areas than Apoe-/- mice. Compared with Apoe-/- mice, atherosclerotic lesions in aged Nox4-/-/Apoe-/- showed reduced cellular and mitochondrial ROS and oxidative DNA damage, lower necrotic core area, higher collagen content, and decreased inflammatory cytokine expression. Immunofluorescence and flow cytometry analysis revealed that aged Apoe-/- mice had a higher percentage of classically activated pro-inflammatory macrophages (CD38+CD80+) in the lesions. Aged Nox4-/-/Apoe-/- mice had a significantly higher proportion of alternatively activated pro-resolving macrophages (EGR2+/CD163+CD206+) in the lesions, with an increased CD38+/EGR2+ cell ratio compared with Apoe-/- mice. Mitochondrial respiration assessment revealed impaired oxidative phosphorylation and increased glycolytic ATP production in macrophages from aged Apoe-/- mice. In contrast, macrophages from Nox4-/-/Apoe-/- mice were less glycolytic and more aerobic, with preserved basal and maximal respiration and mitochondrial ATP production. Macrophages from Nox4-/-/Apoe-/- mice also had lower mitochondrial ROS levels and reduced IL1β secretion; flow cytometry analysis showed fewer CD38+ cells after IFNγ+LPS treatment and more EGR2+ cells after IL4 treatment than in Apoe-/- macrophages. In aged Apoe-/- mice, inhibition of NOX4 activity using GKT137831 significantly reduced macrophage mitochondrial ROS and improved mitochondrial function, resulting in decreased CD68+CD80+ and increased CD163+CD206+ lesion macrophage proportion and attenuated atherosclerosis.
UNASSIGNED: Our findings suggest that increased NOX4 in aging drives macrophage mitochondrial dysfunction, glycolytic metabolic switch, and pro-inflammatory phenotype, advancing atherosclerosis. Inhibiting NOX4 or mitochondrial dysfunction could alleviate vascular inflammation and atherosclerosis, preserving plaque integrity.
摘要：
■衰老会增加动脉粥样硬化性血管疾病及其并发症的风险。巨噬细胞在血管老化的发病机制中至关重要，驱动炎症和动脉粥样硬化进展。NOX4(NADPH氧化酶4)表达随年龄增长而增加,与线粒体功能障碍相关，炎症,和动脉粥样硬化。我们假设NOX4依赖的线粒体氧化应激通过引起巨噬细胞的代谢功能障碍和炎症表型转换来促进衰老相关的动脉粥样硬化进展。
■我们研究了年轻（5个月大）和老年（16个月大）Nox4-/-/Apoe-/-和Apoe-/-喂食西方饮食的小鼠的动脉粥样硬化病变形态和巨噬细胞表型。
■年轻Nox4-/-/Apoe-/-和Apoe-/-小鼠的主动脉和头臂动脉粥样硬化病变横截面积相当。与年轻小鼠相比，老年小鼠的病变面积显着增加。老年Nox4-/-/Apoe-/-小鼠的病变面积明显低于Apoe-/-小鼠。与Apo-/-小鼠相比，老年人的动脉粥样硬化病变Nox4-/-/Apo-/-显示细胞和线粒体ROS和氧化DNA损伤减少，较低的坏死核心区域，胶原蛋白含量较高，炎性细胞因子表达降低。免疫荧光和流式细胞术分析显示，老年Apoe-/-小鼠在病变中具有较高百分比的经典活化的促炎巨噬细胞（CD38CD80）。衰老的Nox4-/-/Apoe-/-小鼠在病变中具有明显较高比例的选择性激活的促解决巨噬细胞（EGR2/CD163CD206），与Apoe-/-小鼠相比，CD38+/EGR2+细胞比例增加。线粒体呼吸评估显示，老年Apoe-/-小鼠巨噬细胞的氧化磷酸化受损和糖酵解ATP产生增加。相比之下,来自Nox4-/-/Apoe-/-小鼠的巨噬细胞糖酵解较少，有氧，保留基础和最大呼吸和线粒体ATP产生。来自Nox4-/-/Apoe-/-小鼠的巨噬细胞的线粒体ROS水平也较低，IL1β分泌减少；流式细胞术分析显示，与Apoe-/-巨噬细胞相比，IFNγLPS处理后的CD38细胞较少，而IL4处理后的EGR2细胞较多。在衰老的Apo-/-小鼠中，使用GKT137831抑制NOX4活性显着减少巨噬细胞线粒体ROS并改善线粒体功能，导致CD68+CD80+和CD163+CD206+病变巨噬细胞比例降低，动脉粥样硬化减弱。
■我们的研究结果表明，衰老过程中NOX4的增加会导致巨噬细胞线粒体功能障碍，糖酵解代谢开关，和促炎表型，推进动脉粥样硬化。抑制NOX4或线粒体功能障碍可以减轻血管炎症和动脉粥样硬化，保持斑块的完整性。
■我们研究了年轻（5个月大）和老年（16个月大）Nox4-/-/Apoe-/-和Apoe-/-喂食西方饮食的小鼠的动脉粥样硬化病变形态和巨噬细胞表型。
■年轻Nox4-/-/Apoe-/-和Apoe-/-小鼠的主动脉和头臂动脉粥样硬化病变横截面积相当。与年轻小鼠相比，老年小鼠的病变面积显着增加。老年Nox4-/-/Apoe-/-小鼠的病变面积明显低于Apoe-/-小鼠。与Apo-/-小鼠相比，老年人的动脉粥样硬化病变Nox4-/-/Apo-/-显示细胞和线粒体ROS和氧化DNA损伤减少，较低的坏死核心区域，胶原蛋白含量较高，炎性细胞因子表达降低。免疫荧光和流式细胞术分析显示，老年Apoe-/-小鼠在病变中具有较高百分比的经典活化的促炎巨噬细胞（CD38CD80）。衰老的Nox4-/-/Apoe-/-小鼠在病变中具有明显较高比例的选择性激活的促解决巨噬细胞（EGR2/CD163CD206），与Apoe-/-小鼠相比，CD38+/EGR2+细胞比例增加。线粒体呼吸评估显示，老年Apoe-/-小鼠巨噬细胞的氧化磷酸化受损和糖酵解ATP产生增加。相比之下,来自Nox4-/-/Apoe-/-小鼠的巨噬细胞糖酵解较少，有氧，保留基础和最大呼吸和线粒体ATP产生。来自Nox4-/-/Apoe-/-小鼠的巨噬细胞的线粒体ROS水平也较低，IL1β分泌减少；流式细胞术分析显示，与Apoe-/-巨噬细胞相比，IFNγLPS处理后的CD38细胞较少，而IL4处理后的EGR2细胞较多。在衰老的Apo-/-小鼠中，使用GKT137831抑制NOX4活性显着减少巨噬细胞线粒体ROS并改善线粒体功能，导致CD68+CD80+和CD163+CD206+病变巨噬细胞比例降低，动脉粥样硬化减弱。
■我们的研究结果表明，衰老过程中NOX4的增加会导致巨噬细胞线粒体功能障碍，糖酵解代谢开关，和促炎表型，推进动脉粥样硬化。抑制NOX4或线粒体功能障碍可以减轻血管炎症和动脉粥样硬化，保持斑块的完整性。
