Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


New "Control Knobs" for Stem Cells Identified

Natural changes in voltage that occur across the membrane of adult human stem cells are a powerful controlling factor in the process by which these stem cells differentiate, according to research published by Tufts University scientists.

Tufts doctoral student Sarah Sundelacruz, Professor of Biology Michael Levin, and Chair of Biomedical Engineering David L. Kaplan (corresponding author) published their paper "Membrane Potential Controls Adipogenic and Osteogenic Differentiation of Mesenchymal Stem Cells" in the November 17, 2008, issue of PLoS ONE (

"We have found that voltage changes act as a signal to delay or accelerate the decision of a stem cell to drop out of a stem state and differentiate into a specific cell type. This discovery gives scientists in regenerative medicine a new set of control knobs to use in ongoing efforts to shape the behavior of adult stem cells," said Levin. "In addition, by uncovering a new mechanism by which these cells are controlled in the human body, this research suggests potential future diagnostic applications."

Harnessing the potential of stem cells for applications such as wound healing and tissue regeneration is a tantalizing yet daunting task. Although many studies indicate that electrophysiology plays a crucial role in cell proliferation and differentiation, its functional role in stem cell biology is poorly understood.

The Tufts researchers studied the changes in membrane potential (voltage across the membrane) shown by human mesenchymal stem cells (hMSCs) obtained from donor bone marrow as the hMSCs were differentiating into fat and bone cells. They found that hyperpolarization (increased difference between the voltage in the interior and exterior of a cell) was characteristic of differentiated cells compared with undifferentiated cells and that hMSCs show different membrane potential profiles during bone vs. fat differentiation.

To determine whether hyperpolarization was functionally required for differentiation, the scientists depolarized the hMSCs by exposing them either to high levels of extracellular potassium ions or to ouabain, a compound that blocks the transfer of ions in and out of cells. Both treatments disrupted the normal increase in negative voltage that occurs during differentiation and suppressed fat and bone cell differentiation markers.

In contrast, treatment with hyperpolarizing reagents up-regulated bone cell markers – indicating that voltage changes are not merely permissive for differentiation but can act as an instructive signal to either induce or inhibit differentiation.

More study is needed to determine whether hyperpolarization also determines which specific type of cell stem cells will differentiate into, according to the Tufts researchers.

Funding for the study came from the National Science Foundation through the Graduate Research Fellowship Program, the National Institutes of Health through the Tissue Engineering Resource Center, the National Highway Traffic Safety Administration and the U.S. Defense Advanced Research Projects Agency.

Tufts University, located on three Massachusetts campuses in Boston, Medford/Somerville, and Grafton, and in Talloires, France, is recognized among the premier research universities in the United States. Tufts enjoys a global reputation for academic excellence and for the preparation of students as leaders in a wide range of professions. A growing number of innovative teaching and research initiatives span all Tufts campuses, and collaboration among the faculty and students in the undergraduate, graduate and professional programs across the university's schools is widely encouraged.

Kim Thurler | Newswise Science News
Further information:

More articles from Life Sciences:

nachricht First time-lapse footage of cell activity during limb regeneration
25.10.2016 | eLife

nachricht Phenotype at the push of a button
25.10.2016 | Institut für Pflanzenbiochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Greater Range and Longer Lifetime

26.10.2016 | Power and Electrical Engineering

VDI presents International Bionic Award of the Schauenburg Foundation

26.10.2016 | Awards Funding

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

More VideoLinks >>>