Regulation of cell proliferation by intermediate-conductance Ca²⁺-activated potassium and volume-sensitive chloride channels in mouse mesenchymal stem cells

Abstract

2ϩ -activated potassium (IKCa) and volume-sensitive chloride (ICl.vol) channels, in regulating proliferation of mouse MSCs. We found that inhibition of IKCa with clotrimazole and ICl.vol with 5-nitro-1-(3-phenylpropylamino) benzoic acid (NPPB) reduced cell proliferation in a concentration-dependent manner. Knockdown of KCa3.1 or Clcn3 with specific short interference (si)RNAs significantly reduced IKCa or ICl.vol density and channel protein and produced a remarkable suppression of cell proliferation (by 24.4 Ϯ 9.6% and 29.5 Ϯ 7.2%, respectively, P Ͻ 0.05 vs. controls). Flow cytometry analysis showed that mouse MSCs retained at G0/G1 phase (control: 51.65 Ϯ 3.43%) by inhibiting IKCa or ICl.vol using clotrimazole (2 M: 64.45 Ϯ 2.20%, P Ͻ 0.05) or NPPB (200 M: 82.89 Ϯ 2.49%, P Ͻ 0.05) or the specific siRNAs, meanwhile distribution of cells in S phase was decreased. Western blot analysis revealed a reduced expression of the cell cycle regulatory proteins cyclin D1 and cyclin E. Collectively, our results have demonstrated that IKCa and ICl.vol channels regulate cell cycle progression and proliferation of mouse MSCs by modulating cyclin D1 and cyclin E expression.

KCa3.1 channels mediate the increase of cell migration and proliferation by advanced glycation endproducts in cultured rat vascular smooth muscle cells

“…21 The detached VSMCs were placed into a 0.2-ml cell chamber mounted on inverted microscope, allowed to settle to the bottom (B20 min), and then superfused with Tyrode solution (pH 7.4) containing (mM): 136 NaCl, 5.4 KCl, 1.0 MgCl 2 , 1.8 CaCl 2 , 10 glucose, and 10 HEPES. Borosilicate glass electrodes (1.2 mm outer diameter) were pulled with a Brown-Flaming puller (Model P-97; Sutter Instrument, Novato, CA, USA) and had a resistance of 2-3 MO when filled with pipette solution containing (mM): 120 K-aspartate, 20 KCl, 1.0 MgCl 2 , 5.0 EGTA, 5 Na-phosphocreatine, 5 Mg-ATP, 0.1 GTP, 10 HEPES, 500 nM free Ca 2 þ with pH adjusted to 7.2 with KOH.…”

The Intermediate Conductance Calcium-activated Potassium Channel KCa3.1 Regulates Vascular Smooth Muscle Cell Proliferation via Controlling Calcium-dependent Signaling

“…KCa3.1 is highly expressed in a variety of nonexcitable and proliferating cells (2), and an increase in KCa3.1 expression has been associated with cancer development, immune disorders, and vascular inflammation. In particular, this channel plays a critical role in the proliferation of smooth muscle cells (3,4), endothelial cells (5), lymphocytes including B-and T-cells (6,7), fibroblasts (8), stem cells (9), and several cancer cells (10).…”

Electrophysiological properties of human induced pluripotent stem cells

“…For instance, the complex interplays of ionic channels in neuronal, muscle, and pancreatic cells shape their action potential profiles and, subsequently, physiological functions from cognition to heart pumping and insulin secretion. As for inexcitable cells, several K ϩ channels have been implicated in the proliferation, cell cycle transition, and apoptosis of mesenchymal stem cells (MSCs) and tumor cells (3,5,6,9,10,19,20). Previously, we reported (24) that several specialized ion channels are functionally expressed in hESCs.…”