High glucose induces formation of tau hyperphosphorylation via Cav-1-mTOR pathway: A potential molecular mechanism for diabetes-induced cognitive dysfunction
Year: 2017
Type: article
Abstract: // Jing Wu 1 , Shan-Lei Zhou 1 , Lin-Hua Pi 1 , Xia-Jie Shi 1 , Ling-Ran Ma 2 , Zi Chen 1 , Min-Li Qu 1 , Xin Li 2 , Sheng-Dan Nie 3 , Duan-Fang Liao 4 , Jin-Jing Pei 5, 6, 7 and Shan Wang 1, 2 1 Department of Endocrinology, Xiang-Ya Hospital, Central South University, Changsha, Hunan, China 2 Department of Pharmaceutical Engineering, College of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan, China 3 Institute of Clinical Medicine, People’s Hospital of Hunan Province, The First Affiliated Hospital of Hunan Normal University, Changsha, Hunan, China 4 Division of Stem Cell Regulation and Application, School of Pharmacy, Hunan University of Traditional Chinese Medicine, Changsha, Hunan, China 5 KI-Alzheimer’s Disease Research Center, Karolinska Institutet, Novum, Stockholm, Sweden 6 Department of Neurology, Xuan Wu Hospital, Capital Medical University, Xicheng, Beijing, China 7 Center of Alzheimer’s Disease, Beijing Institute for Brain Disorders, Beijing, China Correspondence to: Shan Wang, email: [email protected] Jing Wu, email: [email protected] Keywords: diabetes mellitus, cognitive dysfunction, caveolin-1, tau hyperphosphorylation, mTOR Received: February 20, 2017 Accepted: April 07, 2017 Published: April 19, 2017 ABSTRACT The abnormally hyperphosphorylated tau is thought to be implicated in diabetes-associated cognitive deficits. The role of mammalian target of rapamycin (mTOR) / S6 kinase (S6K) signalling in the formation of tau hyperphosphorylation has been previously studied. Caveolin-1 (Cav-1), the essential structure protein of caveolae, promotes neuronal survival and growth, and inhibits glucose metabolism. In this study, we aimed to investigate the role of Cav-1 in the formation of tau hyperphosphorylation under chronic hyperglycemic condition (HGC). Diabetic rats were induced by streptozotocin (STZ). Primary hippocampal neurons with or without molecular intervention such as the transient over-expression or knock-down were subjected to HGC. The obtained experimental samples were analyzed by real time quantitative RT-PCR, Western blot, immunofluorescence or immunohistochemisty. We found: 1) that a chronic HGC directly decreases Cav-1 expression, increases tau phosphorylation and activates mTOR/S6K signalling in the brain neurons of diabetic rats, 2) that overexpression of Cav-1 attenuates tau hyperphosphorylation induced by chronic HGC in primary hippocampal neurons, whereas down-regulation of Cav-1 using Cav-1 siRNA dramatically worsens tau hyperphosphorylation via mTOR/S6K signalling pathway, and 3) that the down-regulation of Cav-1 induced by HGC is independent of mTOR signalling. Our results suggest that tau hyperphosphorylation and the sustained over-activated mTOR signalling under hyperglycemia may be due to the suppression of Cav-1. Therefore, Cav-1 is a potential therapeutic target for diabetes-induced cognitive dysfunction.
Source: Oncotarget
Authors: Jing Wu, Shan-Lei Zhou, Lin-Hua Pi, Xia-Jie Shi, Ling-Ran Ma, Zi Chen, Min-Li Qu, Xin Li, Sheng-Dan Nie, Duan-Fang Liao, Jin-Jing Pei, Shan Wang
Institutions: Central South University, Xiangya Hospital Central South University, Hunan Provincial People's Hospital, Hunan University of Traditional Chinese Medicine, Capital Medical University, Karolinska Institutet, Xuan Wu Hospital of the Capital Medical University, Beijing Institute for Brain Disorders
Language: English
Subfield: Cellular and Molecular Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: diamond
OpenAlex ID: W2607382890