Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecu...Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their development.This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor EB.Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal diseases.The review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal disorders.The impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways.In vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal microvasculature.Additionally,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and atherogenesis.In retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization.These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering protection against retinal aging and diseases.The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases.Therefore,it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects.展开更多
目的:探讨CD38对巨噬细胞溶酶体再生及胆固醇外流的影响。方法:以低密度脂蛋白(LDL)受体敲除(LDLr^(-/-))小鼠的骨髓源性巨噬细胞为细胞模型。采用活细胞成像系统观察烟酸腺嘌呤二核苷酸磷酸(NAADP)对巨噬细胞溶酶体数量的影响;利用ELIS...目的:探讨CD38对巨噬细胞溶酶体再生及胆固醇外流的影响。方法:以低密度脂蛋白(LDL)受体敲除(LDLr^(-/-))小鼠的骨髓源性巨噬细胞为细胞模型。采用活细胞成像系统观察烟酸腺嘌呤二核苷酸磷酸(NAADP)对巨噬细胞溶酶体数量的影响;利用ELISA检测巨噬细胞内NAADP的水平;细胞经NA处理后,利用RT-q PCR检测CD38 m RNA表达,利用Western blot检测CD38蛋白表达和转录因子EB(TFEB)磷酸化水平;利用激光共聚焦技术观察CD38/NAADP信号通路对溶酶体数量和胆固醇外流的影响。结果:NAADP可显著增加巨噬细胞中溶酶体的数量(P<0.05),这种效应可被NAADP拮抗剂NED-19、Ca^(2+)螯合剂BAPTA及钙调磷酸酶抑制剂Cs A明显抑制(P<0.05);CD38可明显促进巨噬细胞中NAADP的合成(P<0.05);NAADP合成底物NA可明显促进CD38 m RNA和蛋白表达(P<0.05);NA还可显著降低TFEB的磷酸化水平,且这一效应也可被NED-19、BAPTA和Cs A明显抑制(P<0.05);阻断CD38/NAADP信号通路可明显抑制NA诱导的溶酶体数量增加和溶酶体游离胆固醇及胞质胆固醇酯的外流(P<0.05);在LDLr/CD38双基因敲除巨噬细胞中,NA诱导的溶酶体数量增加和溶酶体游离胆固醇及胞质胆固醇酯的外流效应消失,CD38基因回补后,这一效应即可恢复(P<0.05)。结论:CD38可经TFEB介导,触发巨噬细胞溶酶体再生,进而促进巨噬细胞溶酶体游离胆固醇和胞质中胆固醇酯的外流。展开更多
基金supported by the Start-up Fund for new faculty from the Hong Kong Polytechnic University(PolyU)(A0043215)(to SA)the General Research Fund and Research Impact Fund from the Hong Kong Research Grants Council(15106018,R5032-18)(to DYT)+1 种基金the Research Center for SHARP Vision in PolyU(P0045843)(to SA)the InnoHK scheme from the Hong Kong Special Administrative Region Government(to DYT).
文摘Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their development.This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor EB.Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal diseases.The review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal disorders.The impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways.In vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal microvasculature.Additionally,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and atherogenesis.In retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization.These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering protection against retinal aging and diseases.The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases.Therefore,it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects.
文摘目的:探讨CD38对巨噬细胞溶酶体再生及胆固醇外流的影响。方法:以低密度脂蛋白(LDL)受体敲除(LDLr^(-/-))小鼠的骨髓源性巨噬细胞为细胞模型。采用活细胞成像系统观察烟酸腺嘌呤二核苷酸磷酸(NAADP)对巨噬细胞溶酶体数量的影响;利用ELISA检测巨噬细胞内NAADP的水平;细胞经NA处理后,利用RT-q PCR检测CD38 m RNA表达,利用Western blot检测CD38蛋白表达和转录因子EB(TFEB)磷酸化水平;利用激光共聚焦技术观察CD38/NAADP信号通路对溶酶体数量和胆固醇外流的影响。结果:NAADP可显著增加巨噬细胞中溶酶体的数量(P<0.05),这种效应可被NAADP拮抗剂NED-19、Ca^(2+)螯合剂BAPTA及钙调磷酸酶抑制剂Cs A明显抑制(P<0.05);CD38可明显促进巨噬细胞中NAADP的合成(P<0.05);NAADP合成底物NA可明显促进CD38 m RNA和蛋白表达(P<0.05);NA还可显著降低TFEB的磷酸化水平,且这一效应也可被NED-19、BAPTA和Cs A明显抑制(P<0.05);阻断CD38/NAADP信号通路可明显抑制NA诱导的溶酶体数量增加和溶酶体游离胆固醇及胞质胆固醇酯的外流(P<0.05);在LDLr/CD38双基因敲除巨噬细胞中,NA诱导的溶酶体数量增加和溶酶体游离胆固醇及胞质胆固醇酯的外流效应消失,CD38基因回补后,这一效应即可恢复(P<0.05)。结论:CD38可经TFEB介导,触发巨噬细胞溶酶体再生,进而促进巨噬细胞溶酶体游离胆固醇和胞质中胆固醇酯的外流。