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Tingskov SJ, Choi HJ, Holst MR, Hu S, Li C, Wang W, Frøkiær J, Nejsum LN, Kwon TH, Nørregaard R. Vasopressin-Independent Regulation of Aquaporin-2 by Tamoxifen in Kidney Collecting Ducts. Front Physiol 2019; 10:948. [PMID: 31447686 PMCID: PMC6695565 DOI: 10.3389/fphys.2019.00948] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 07/09/2019] [Indexed: 12/11/2022] Open
Abstract
Arginine vasopressin (AVP) mediates water reabsorption in the kidney collecting ducts through regulation of aquaporin-2 (AQP2). Also, estrogen has been known to regulate AQP2. Consistently, we previously demonstrated that tamoxifen (TAM), a selective estrogen receptor modulator, attenuates the downregulation of AQP2 in lithium-induced nephrogenic diabetes insipidus (NDI). In this study, we investigated the AVP-independent regulation of AQP2 by TAM and the therapeutic effect of TAM on the dysregulation of AQP2 and impaired urinary concentration in a unilateral ureteral obstruction (UUO) model. Primary cultured inner medullary collecting duct (IMCD) cells from kidneys of male Sprague-Dawley rats were treated with TAM. Rats subjected to 7 days of UUO were treated with TAM by oral gavage. Changes of intracellular trafficking and expression of AQP2 were evaluated by quantitative PCR, Western blotting, and immunohistochemistry. TAM induced AQP2 protein expression and intracellular trafficking in primary cultured IMCD cells, which were independent of the vasopressin V2 receptor (V2R) and cAMP activation, the critical pathways involved in AVP-stimulated regulation of AQP2. TAM attenuated the downregulation of AQP2 in TGF-β treated IMCD cells and IMCD suspensions prepared from UUO rats. TAM administration in vivo attenuated the downregulation of AQP2, associated with an improvement of urinary concentration in UUO rats. In addition, TAM increased CaMKII expression, suggesting that calmodulin signaling pathway is likely to be involved in the TAM-mediated AQP2 regulation. In conclusion, TAM is involved in AQP2 regulation in a vasopressin-independent manner and improves urinary concentration by attenuating the downregulation of AQP2 and maintaining intracellular trafficking in UUO.
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Affiliation(s)
| | - Hyo-Jung Choi
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Daegu, South Korea
| | - Mikkel R Holst
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Shan Hu
- Zhongshan School of Medicine, Institute of Hypertension, Sun Yat-sen University, Guangzhou, China
| | - Chunling Li
- Zhongshan School of Medicine, Institute of Hypertension, Sun Yat-sen University, Guangzhou, China
| | - Weidong Wang
- Zhongshan School of Medicine, Institute of Hypertension, Sun Yat-sen University, Guangzhou, China
| | - Jørgen Frøkiær
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Lene N Nejsum
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Tae-Hwan Kwon
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Daegu, South Korea
| | - Rikke Nørregaard
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
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Soeda F, Hirakawa E, Inoue M, Shirasaki T, Takahama K. Cloperastine rescues impairment of passive avoidance response in mice prenatally exposed to diethylstilbestrol. ENVIRONMENTAL TOXICOLOGY 2014; 29:216-225. [PMID: 22223406 DOI: 10.1002/tox.21749] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 11/11/2011] [Accepted: 11/13/2011] [Indexed: 05/31/2023]
Abstract
We previously reported that prenatal exposure to diethylstilbestrol (DES) impaired passive avoidance responses in mice. Apart from the above, we also found that cloperastine, a centrally acting antitussive, ameliorated depression-like and anxiety-like behaviors in rodents at antitussive-effective doses. In this study, we investigated whether or not cloperastine rescues impairment of passive avoidance responses in mice prenatally exposed to DES. Male DES-exposed mice were subcutaneously administered cloperastine at 10 or 30 mg/kg twice a day from 32 to 41 days after birth and subjected to behavioral testing 42 to 46 days after birth. Cloperastine at 10 and 30 mg/kg ameliorated DES-induced impairment of passive avoidance responses. In addition, cloperastine affected the levels of 5-HT1A receptors, GIRK and BDNF in the hippocampus of DES-exposed mice. However, the number of BrdU-positive cells in the hippocampus of DES-exposed mice was not changed by chronic administration of cloperastine. These findings suggest that the action of endocrine disruptors in the brain may not always be irreversible, and that the symptoms caused by endocrine disruptors might be curable with drugs such as cloperastine.
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Affiliation(s)
- Fumio Soeda
- Department of Environmental and Molecular Health Sciences, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Kumamoto 862-0973, Japan
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