Aquaporin-2 Promoter Is Synergistically Regulated by Nitric Oxide and Nuclear Factor of Activated T Cells

We have previously shown that aquaporin-2 (AQP2) is down-regulated in the renal medulla of rats made hypertensive by chronic inhibition of nitric oxide synthase. It has been shown that AQP2 expression is regulated by the calcineurin/nuclear factor of activated T cells (NFATc). Nitric oxide (NO) regu...

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Detalles Bibliográficos
Autores: Albertoni Borghese, Florencia, Bettini, Layne M., Nitta, Carlos H., Frutos García, Sergio de|||0000-0002-1225-5911, Majowicz, Mónica, González Bosc, Laura Verónica
Tipo de recurso: artículo
Fecha de publicación:2011
País:España
Institución:Universidad de Alcalá (UAH)
Repositorio:e_Buah Biblioteca Digital Universidad de Alcalá
Idioma:inglés
OAI Identifier:oai:ebuah.uah.es:10017/61040
Acceso en línea:http://hdl.handle.net/10017/61040
https://dx.doi.org/10.1159/000333066
Access Level:acceso abierto
Palabra clave:Renal papilla
AQP2
MDCK cells
NFATc
Nitric oxide
Nuclear factor
Medicina
Medicine
Descripción
Sumario:We have previously shown that aquaporin-2 (AQP2) is down-regulated in the renal medulla of rats made hypertensive by chronic inhibition of nitric oxide synthase. It has been shown that AQP2 expression is regulated by the calcineurin/nuclear factor of activated T cells (NFATc). Nitric oxide (NO) regulates the activity of NFATc via c-Jun-N-terminal kinase 2 (JNK2). Therefore, we hypothesized that increases in NO enhance NFATc-mediated up-regulation of AQP2 promoter activity. Methods: AQP2 mRNA and protein expression were detected in mouse renal papilla.AQP2 promoter luciferase reporter- and NFAT luciferase reporter-transfected MDCK cells were used to determine AQP2 promoter activity and NFATc activity, respectively. Cells were incubated with classic activators and inhibitors of NFATc and the NO pathway. Results: Our results demonstrate that both Ca2+ and NO have a synergistic effect resulting in an increase in AQP2 mRNA and protein in mouse papilla and activation of the AQP2 promoter in kidney-derived cells. In addition, NO enhances Ca2+-induced NFATc activation. The underlying mechanism involves increased NFATc nuclear import and decreased export via protein kinase G-mediated inhibition of JNK1/2. Conclusions: This is the first study defining novel regulatory roles for NO and NFATc in the control of AQP2, which is an important renal protein.