Faculty Collaboration Database

Electrophysiological properties of human adipose tissue-derived stem cells. Am J Physiol Cell Physiol 2007 Nov;293(5):C1539-50

Date

08/10/2007

Pubmed ID

17687001

DOI

10.1152/ajpcell.00089.2007

Scopus ID

2-s2.0-36048950644 (requires institutional sign-in at Scopus site)   82 Citations

Abstract

Human adipose tissue-derived stem cells (hASCs) represent a potentially valuable cell source for clinical therapeutic applications. The present study was designed to investigate properties of ionic channel currents present in undifferentiated hASCs and their impact on hASCs proliferation. The functional ion channels in hASCs were analyzed by whole-cell patch-clamp recording and their mRNA expression levels detected by RT-PCR. Four types of ion channels were found to be present in hASCs: most of the hASCs (73%) showed a delayed rectifier-like K(+) current (I(KDR)); Ca(2+)-activated K(+) current (I(KCa)) was detected in examined cells; a transient outward K(+) current (I(to)) was recorded in 19% of the cells; a small percentage of cells (8%) displayed a TTX-sensitive transient inward sodium current (I(Na.TTX)). RT-PCR results confirmed the presence of ion channels at the mRNA level: Kv1.1, Kv2.1, Kv1.5, Kv7.3, Kv11.1, and hEAG1, possibly encoding I(KDR); MaxiK, KCNN3, and KCNN4 for I(KCa); Kv1.4, Kv4.1, Kv4.2, and Kv4.3 for I(to) and hNE-Na for I(Na.TTX). The I(KDR) was inhibited by tetraethyl ammonium (TEA) and 4-aminopyridine (4-AP), which significantly reduced the proliferation of hASCs in a dose-dependent manner (P < 0.05), as suggested by bromodeoxyurindine (BrdU) incorporation. Other selective potassium channel blockers, including linopiridine, iberiotoxin, clotrimazole, and apamin also significantly inhibited I(KDR). TTX completely abolished I(Na.TTX). This study demonstrates for the first time that multiple functional ion channel currents such as I(KDR), I(KCa), I(to), and I(Na.TTX) are present in undifferentiated hASCs and their potential physiological function in these cells as a basic understanding for future in vitro experiments and in vivo clinical investigations.

Author List

Bai X, Ma J, Pan Z, Song YH, Freyberg S, Yan Y, Vykoukal D, Alt E

Author

Xiaowen Bai PhD Associate Professor in the Cell Biology, Neurobiology and Anatomy department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adipose Tissue
Adult Stem Cells
Blotting, Western
Cell Differentiation
Cell Proliferation
Cell Survival
Cells, Cultured
Delayed Rectifier Potassium Channels
Dose-Response Relationship, Drug
Humans
Membrane Potentials
Patch-Clamp Techniques
Potassium
Potassium Channel Blockers
Potassium Channels, Calcium-Activated
RNA, Messenger
Reverse Transcriptase Polymerase Chain Reaction
Sodium
Sodium Channel Blockers
Sodium Channels
Tetrodotoxin