Weifeng Xu1, Yujie Huang2, Lei Li2, Zhen Sun2, Yachen Shen2, Jing Xing2, Min Li2, Dongming Su3, Xiubin Liang4. 1. Department of Pathophysiology, Nanjing Medical University, Nanjing, Jiangsu Province, China; Zhuji people Hospital, Zhuji, Zhejiang Province, China. 2. Department of Pathophysiology, Nanjing Medical University, Nanjing, Jiangsu Province, China. 3. Department of Pathology, Nanjing Medical University, Nanjing, Jiangsu Province, China; State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu Province, China. 4. Department of Pathophysiology, Nanjing Medical University, Nanjing, Jiangsu Province, China; State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu Province, China. Electronic address: liangxiubin@njmu.edu.cn.
Abstract
OBJECTIVES: The mechanisms leading to hypertension associated with hyperuricemia are still unclear. The activity of the distal nephron epithelial sodium channel (ENaC) is an important determinant of sodium balance and blood pressure. Our aim was to investigate whether the effect of hyperuricemia on blood pressure is related to ENaC activation. METHODS: A hyperuricemic model was induced in rats by 2% oxonic acid and 6 mg/dl uric acid (UA). The hyperuricemic rats were co-treated with either 10mg/kg/d benzbromarone (Ben) or 1 mg/kg/d amiloride (Ami). Blood pressure was monitored using a tail-cuff, and blood, urine, and kidney samples were taken. Western blotting and immunohistochemical staining were performed to determine the expressions of ENaC subunits and components of the ENaC Regulatory Complex (ERC) in kidney tissue or mCCD cells. RESULTS: Serum uric acid (SUA) was increased 2.5-3.5 times above normal in hyperuricemic rats after 3 weeks and remained at these high levels until 6 weeks. The in vivo rise in SUA was followed by elevated blood pressure, renal tubulointerstitial injury, and increased expressions of ENaC subunits, SGK1, and GILZ1, which were prevented by Ben treatment. The decrease in urinary Na(+) excretion in hyperuricemic rats was blunted by Ami. UA induced the expression of all three ENaC subunits, SGK1, and GILZ1, and increased Na(+) transport in mCCD cells. Phosphorylation of ERK was significantly decreased in both UA-treated mCCD cells and hyperuricemic rat kidney; this effect was prevented by Ben co-treatment. CONCLUSION: Our findings suggest that elevated serum uric acid could induce hypertension by activation of ENaC and regulation of ERC expression.
OBJECTIVES: The mechanisms leading to hypertension associated with hyperuricemia are still unclear. The activity of the distal nephron epithelial sodium channel (ENaC) is an important determinant of sodium balance and blood pressure. Our aim was to investigate whether the effect of hyperuricemia on blood pressure is related to ENaC activation. METHODS: A hyperuricemic model was induced in rats by 2% oxonic acid and 6 mg/dl uric acid (UA). The hyperuricemicrats were co-treated with either 10mg/kg/d benzbromarone (Ben) or 1 mg/kg/d amiloride (Ami). Blood pressure was monitored using a tail-cuff, and blood, urine, and kidney samples were taken. Western blotting and immunohistochemical staining were performed to determine the expressions of ENaC subunits and components of the ENaC Regulatory Complex (ERC) in kidney tissue or mCCD cells. RESULTS: Serum uric acid (SUA) was increased 2.5-3.5 times above normal in hyperuricemicrats after 3 weeks and remained at these high levels until 6 weeks. The in vivo rise in SUA was followed by elevated blood pressure, renal tubulointerstitial injury, and increased expressions of ENaC subunits, SGK1, and GILZ1, which were prevented by Ben treatment. The decrease in urinary Na(+) excretion in hyperuricemicrats was blunted by Ami. UA induced the expression of all three ENaC subunits, SGK1, and GILZ1, and increased Na(+) transport in mCCD cells. Phosphorylation of ERK was significantly decreased in both UA-treated mCCD cells and hyperuricemicrat kidney; this effect was prevented by Ben co-treatment. CONCLUSION: Our findings suggest that elevated serum uric acid could induce hypertension by activation of ENaC and regulation of ERC expression.
Authors: Richard J Johnson; Laura G Sánchez-Lozada; Takahiko Nakagawa; Bernardo Rodriguez-Iturbe; Dean Tolan; Eric A Gaucher; Peter Andrews; Miguel A Lanaspa Journal: Obesity (Silver Spring) Date: 2022-10 Impact factor: 9.298
Authors: Annayya R Aroor; Guanghong Jia; Javad Habibi; Zhe Sun; Francisco I Ramirez-Perez; Barron Brady; Dongqing Chen; Luis A Martinez-Lemus; Camila Manrique; Ravi Nistala; Adam T Whaley-Connell; Vincent G Demarco; Gerald A Meininger; James R Sowers Journal: Metabolism Date: 2017-06-21 Impact factor: 8.694