Selective Down-regulation of KV2.1 Function Contributes to Enhanced Arterial Tone During Diabetes
Overview
Authors
Affiliations
Enhanced arterial tone is a leading cause of vascular complications during diabetes. Voltage-gated K(+) (KV) channels are key regulators of vascular smooth muscle cells (VSMCs) contractility and arterial tone. Whether impaired KV channel function contributes to enhance arterial tone during diabetes is unclear. Here, we demonstrate a reduction in KV-mediated currents (IKv) in VSMCs from a high fat diet (HFD) mouse model of type 2 diabetes. In particular, IKv sensitive to stromatoxin (ScTx), a potent KV2 blocker, were selectively reduced in diabetic VSMCs. This was associated with decreased KV2-mediated regulation of arterial tone and suppression of the KV2.1 subunit mRNA and protein in VSMCs/arteries isolated from HFD mice. We identified protein kinase A anchoring protein 150 (AKAP150), via targeting of the phosphatase calcineurin (CaN), and the transcription factor nuclear factor of activated T-cells c3 (NFATc3) as required determinants of KV2.1 suppression during diabetes. Interestingly, substantial reduction in transcript levels for KV2.1 preceded down-regulation of large conductance Ca(2+)-activated K(+) (BKCa) channel β1 subunits, which are ultimately suppressed in chronic hyperglycemia to a similar extent. Together, our study supports the concept that transcriptional suppression of KV2.1 by activation of the AKAP150-CaN/NFATc3 signaling axis contributes to enhanced arterial tone during diabetes.
Har K, Lysenko N, Dimitrova D, Schluter T, Zavaritskaya O, Kamkin A Cells. 2023; 12(15).
PMID: 37566068 PMC: 10416909. DOI: 10.3390/cells12151989.
Diversity of cells and signals in the cardiovascular system.
Grandi E, Navedo M, Saucerman J, Bers D, Chiamvimonvat N, Dixon R J Physiol. 2023; 601(13):2547-2592.
PMID: 36744541 PMC: 10313794. DOI: 10.1113/JP284011.
Mechanisms of Vascular Ca1.2 Channel Regulation During Diabetic Hyperglycemia.
Martin-Aragon Baudel M, Hong J, Hell J, Nieves-Cintron M, Navedo M Handb Exp Pharmacol. 2023; 279:41-58.
PMID: 36598607 DOI: 10.1007/164_2022_628.
Leo M, Peixoto-Nieves D, Yin W, Raghavan S, Muralidharan P, Mata-Daboin A Am J Physiol Heart Circ Physiol. 2021; 320(3):H1089-H1101.
PMID: 33449847 PMC: 7988758. DOI: 10.1152/ajpheart.00690.2020.
AKAP5 complex facilitates purinergic modulation of vascular L-type Ca channel Ca1.2.
Prada M, Syed A, Reddy G, Martin-Aragon Baudel M, Flores-Tamez V, Sasse K Nat Commun. 2020; 11(1):5303.
PMID: 33082339 PMC: 7575592. DOI: 10.1038/s41467-020-18947-y.