Abstract

O-GlcNAcylation, an energy-sensitive posttranslational modification, can regulate the activity of endothelial nitric oxide synthase (eNOS). Previous studies found that Thr866 is the key site for low-glucose-mediated regulation of eNOS O-GlcNAc. However, it is not known whether this activity functions through the Thr866 site concomitant with other physical and chemical factors. Therefore, we first explored the effects of physical and chemical factors on eNOS O-GlcNAc and its Thr866 site. In this study, hypertonic stress, hyperthermia and hydrogen peroxide all increased the expression levels of eNOS O-GlcNAc, whereas hypoxia and high levels of alcohol had no effect. on the expression levels of eNOS O-GlcNAc; by contrast, low pH led to a decrease in eNOS O-GlcNAc levels. Notably, eNOS O-GlcNAc protein levels were unchanged after Thr866 site mutation only under hypertonic conditions, suggesting that hypertonic stress may act through the Thr866 site. Upon exploring the mechanism of hypertonic stress on eNOS O-GlcNAc activity and function, we found that hypertonic stress can upregulate the expression of O-linked N-acetylglucosamine (GlcNAc) transferase (OGT), which is dependent on AMPK. When AMPK was knocked out, the upregulation of OGT expression and increased O-GlcNAc modifications induced by hypertonic stress were reversed.

Details

Title
Hypertonic stress modulates eNOS function through O-GlcNAc modification at Thr-866
Author
Chang, Li 1 ; He, An 2 ; Guo Yongzheng 1 ; Yang Xiyang 1 ; Luo Minghao 1 ; Cheng, Zhe 1 ; Huang Longxiang 1 ; Xia, Yong 3 ; Luo Suxin 2 

 The First Affiliated Hospital of Chongqing Medical University, Division of Cardiology, Chongqing, China (GRID:grid.452206.7); Chongqing Medical University, Institute of Life Science, Chongqing, China (GRID:grid.203458.8) (ISNI:0000 0000 8653 0555) 
 The First Affiliated Hospital of Chongqing Medical University, Division of Cardiology, Chongqing, China (GRID:grid.452206.7) 
 The First Affiliated Hospital of Chongqing Medical University, Division of Cardiology, Chongqing, China (GRID:grid.452206.7); Chongqing Medical University, Institute of Life Science, Chongqing, China (GRID:grid.203458.8) (ISNI:0000 0000 8653 0555); Davis Heart and Lung Research Institute, The Ohio State University College of Medicine, Division of Cardiovascular Medicine, Department of Molecular and Cellular Biochemistry, Columbus, USA (GRID:grid.261331.4) (ISNI:0000 0001 2285 7943) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2533558839
Copyright
© The Author(s) 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.