PMID- 35179568 OWN - NLM STAT- MEDLINE DCOM- 20220422 LR - 20220610 IS - 1939-327X (Electronic) IS - 0012-1797 (Linking) VI - 71 IP - 5 DP - 2022 May 1 TI - Restoration of Autophagic Flux Improves Endothelial Function in Diabetes Through Lowering Mitochondrial ROS-Mediated eNOS Monomerization. PG - 1099-1114 LID - 10.2337/db21-0660 [doi] AB - Endothelial nitric oxide synthase (eNOS) monomerization and uncoupling play crucial roles in mediating vascular dysfunction in diabetes, although the underlying mechanisms are still incompletely understood. Increasing evidence indicates that autophagic dysregulation is involved in the pathogenesis of diabetic endothelial dysfunction; however, whether autophagy regulates eNOS activity through controlling eNOS monomerization or dimerization remains elusive. In this study, autophagic flux was impaired in the endothelium of diabetic db/db mice and in human endothelial cells exposed to advanced glycation end products or oxidized low-density lipoprotein. Inhibition of autophagic flux by chloroquine or bafilomycin A1 were sufficient to induce eNOS monomerization and lower nitric oxide bioavailability by increasing mitochondrial reactive oxygen species (mtROS). Restoration of autophagic flux by overexpressing transcription factor EB (TFEB), a master regulator of autophagy and lysosomal biogenesis, decreased endothelial cell oxidative stress, increased eNOS dimerization, and improved endothelium-dependent relaxations (EDRs) in db/db mouse aortas. Inhibition of mammalian target of rapamycin kinase (mTOR) increased TFEB nuclear localization, reduced mtROS accumulation, facilitated eNOS dimerization, and enhanced EDR in db/db mice. Moreover, calorie restriction also increased TFEB expression, improved autophagic flux, and restored EDR in the aortas of db/db mice. Taken together, the findings of this study reveal that mtROS-induced eNOS monomerization is closely associated with the impaired TFEB-autophagic flux axis leading to endothelial dysfunction in diabetic mice. CI - (c) 2022 by the American Diabetes Association. FAU - Zhao, Lei AU - Zhao L AD - Shenzhen Research Institute and School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China. FAU - Zhang, Cheng-Lin AU - Zhang CL AD - Department of Pathophysiology, School of Basic Medical Sciences, Shenzhen University Health Science Center, Shenzhen, China. FAU - He, Lei AU - He L AD - Shenzhen Research Institute and School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China. FAU - Chen, Qinghua AU - Chen Q AD - Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China. FAU - Liu, Limei AU - Liu L AD - Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China. FAU - Kang, Lijing AU - Kang L AD - Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China. FAU - Liu, Jian AU - Liu J AD - Shenzhen Research Institute and School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China. FAU - Luo, Jiang-Yun AU - Luo JY AD - Shenzhen Research Institute and School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China. FAU - Gou, Lingshan AU - Gou L AD - Shenzhen Research Institute and School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China. FAU - Qu, Dan AU - Qu D AD - Shenzhen Research Institute and School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China. FAU - Song, Wencong AU - Song W AD - Shenzhen Research Institute and School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China. FAU - Lau, Chi Wai AU - Lau CW AD - Shenzhen Research Institute and School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China. FAU - Ko, Ho AU - Ko H AD - Division of Neurology, Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China. AD - Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China. FAU - Mok, Vincent C T AU - Mok VCT AD - Division of Neurology, Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China. AD - Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China. FAU - Tian, Xiao Yu AU - Tian XY AD - Shenzhen Research Institute and School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China. FAU - Wang, Li AU - Wang L AD - Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China. FAU - Huang, Yu AU - Huang Y AUID- ORCID: 0000-0002-1277-6784 AD - Shenzhen Research Institute and School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China. AD - Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China. LA - eng SI - figshare/10.2337/figshare.19164119 PT - Journal Article PT - Research Support, Non-U.S. Gov't PL - United States TA - Diabetes JT - Diabetes JID - 0372763 RN - 0 (Reactive Oxygen Species) RN - EC 1.14.13.39 (Nitric Oxide Synthase Type III) SB - IM MH - Animals MH - Autophagy MH - *Diabetes Mellitus, Experimental/metabolism MH - Endothelial Cells/metabolism MH - Endothelium, Vascular/metabolism MH - Mammals/metabolism MH - Mice MH - Mice, Inbred C57BL MH - *Nitric Oxide Synthase Type III/genetics/metabolism MH - Reactive Oxygen Species/metabolism EDAT- 2022/02/19 06:00 MHDA- 2022/04/23 06:00 CRDT- 2022/02/18 12:13 PHST- 2021/07/28 00:00 [received] PHST- 2022/02/10 00:00 [accepted] PHST- 2022/02/19 06:00 [pubmed] PHST- 2022/04/23 06:00 [medline] PHST- 2022/02/18 12:13 [entrez] AID - 144595 [pii] AID - 10.2337/db21-0660 [doi] PST - ppublish SO - Diabetes. 2022 May 1;71(5):1099-1114. doi: 10.2337/db21-0660.