Tungstate-targeting of BKaß1 channels tunes ERK phosphorylation and cell proliferation in human vascular smooth muscle

Fernández-Mariño, A.I. ; Cidad, P. ; Zafra, D. ; Nocito, L. ; Domínguez, J. ; Oliván-Viguera, A. ; Köhler, R. ; López-López, J.R. ; Pérez-García, M.T. ; Valverde, M.Á. ; Guinovart, J.J. ; Fernández-Fernández, J.M.

Resumen: Despite the substantial knowledge on the antidiabetic, antiobesity and antihypertensive actions of tungstate, information on its primary target/s is scarce. Tungstate activates both the ERK1/2 pathway and the vascular voltage- and Ca2+-dependent large-conductance BKaß1 potassium channel, which modulates vascular smooth muscle cell (VSMC) proliferation and function, respectively. Here, we have assessed the possible involvement of BKaß1 channels in the tungstate-induced ERK phosphorylation and its relevance for VSMC proliferation. Western blot analysis in HEK cell lines showed that expression of vascular BKaß1 channels potentiates the tungstate-induced ERK1/2 phosphorylation in a Gi/o protein-dependent manner. Tungstate activated BKaß1 channels upstream of G proteins as channel activation was not altered by the inhibition of G proteins with GDPßS or pertussis toxin. Moreover, analysis of Gi/o protein activation measuring the FRET among heterologously expressed Gi protein subunits suggested that tungstate-targeting of BKaß1 channels promotes G protein activation. Single channel recordings on VSMCs from wild-type and ß1-knockout mice indicated that the presence of the regulatory ß1 subunit was essential for the tungstate-mediated activation of BK channels in VSMCs. Moreover, the specific BK channel blocker iberiotoxin lowered tungstate-induced ERK phosphorylation by 55% and partially reverted (by 51%) the tungstate-produced reduction of platelet-derived growth factor (PDGF)-induced proliferation in human VSMCs. Our observations indicate that tungstate-targeting of BKaß1 channels promotes activation of PTX-sensitive Gi proteins to enhance the tungstate-induced phosphorylation of ERK, and inhibits PDGF-stimulated cell proliferation in human vascular smooth muscle.

Idioma: Inglés

DOI: 10.1371/journal.pone.0118148

Año: 2015

Publicado en: PloS one 10, 2 (2015), e0118148[21 pp]
ISSN: 1932-6203

Factor impacto JCR: 3.057 (2015)

Categ. JCR: MULTIDISCIPLINARY SCIENCES rank: 11 / 62 = 0.177 (2015) - Q1 - T1

Factor impacto SCIMAGO: 1.427 - Agricultural and Biological Sciences (miscellaneous) (Q1) - Medicine (miscellaneous) (Q1) - Biochemistry, Genetics and Molecular Biology (miscellaneous) (Q1)

Financiación: info:eu-repo/grantAgreement/EC/FP7/321721/EU/Identification and validation of cerebral KCa3.1/KCa2.3 potassium channels a drug tragets for the prevention and treatment of cerebral ischemia associated with diabetes and Alzheimers disease/BRAINIK
Financiación: info:eu-repo/grantAgreement/ES/ISCIII/RD12-0042-0006
Financiación: info:eu-repo/grantAgreement/ES/ISCIII/RD12-0042-0014
Financiación: info:eu-repo/grantAgreement/ES/MICINN/BFU2008-00769
Financiación: info:eu-repo/grantAgreement/ES/MICINN/BFU2010-15898
Financiación: info:eu-repo/grantAgreement/ES/MINECO/BFU2013-45867-R
Financiación: info:eu-repo/grantAgreement/ES/MINECO-FEDER/SAF2012-31089
Financiación: info:eu-repo/grantAgreement/ES/MINECO-FEDER/SAF2012-38140

Tipo y forma: Article (Published version)