Autophagy is involved in degradation of AQP1 in response to an acute decrement in tonicity
Xiangdong Guo,
Long Xu,
Yonglun Kong,
Meng Li,
Qingxian Zhai,
Baien Liang,
Xiaoduo Zhao,
Luosha Long,
Meiying Huang,
Weidong Wang,
Chunling Li
Affiliations
Xiangdong Guo
Department of Physiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
Long Xu
Department of Physiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
Yonglun Kong
Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; Department of Pathophysiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
Meng Li
Department of Physiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
Qingxian Zhai
Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; Department of Pathophysiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
Baien Liang
Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; Department of Pathophysiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
Xiaoduo Zhao
Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; Department of Pathophysiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
Luosha Long
Department of Physiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
Meiying Huang
Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; Department of Pathophysiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
Weidong Wang
Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; Department of Pathophysiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; Corresponding author
Chunling Li
Department of Physiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; Corresponding author
Summary: Renal medullary aquaporin-1 (AQP1) plays an important role in the urinary concentration. This study aimed to investigate the regulation of AQP1 by low osmotic stress and a potential role of autophagy. Low osmotic stress induced a dramatically decreased AQP1 protein expression in murine inner medullary collecting duct 3 (mIMCD3) cells, which was associated with a marked activation of autophagy. Inhibition of autophagy by 3-methyladenine (3-MA), chloroquine, or knockdown of autophagy-related protein 5 (ATG5) prevented the decrease in AQP1 protein abundance. Rapamycin-induced autophagy was associated with a decreased AQP1 protein expression and an enhanced interaction between AQP1 and ATG5 in mIMCD3 cells under low osmotic stress. In kidney inner medulla of mice given a 3% NaCl solution, activation of autophagy was associated with decreased AQP1 protein expression, which was prevented by 3-MA. In conclusion, low osmotic stress induced autophagy which contributed to the decreased AQP1 protein expression in the renal medulla.
