Researchers at the National Institute of Standards and Technology (NIST) have developed a new method for accurately measuring a key process governing a wide variety of cellular functions that may become the basis for a "health checkup" for living cells.
The NIST technique measures changes in a living cell's internal redox (reduction-oxidation) potential, a chemistry concept that expresses the favorability of reactions in which molecules or atoms either gain or lose electrons. Redox reactions are important to cell chemistry because they regulate many genes and the proteins they produce. An accurate measure of redox potential can provide insight into how well these genes are working, and in turn, whether or not the activities they controlsuch as differentiation and growthare functioning normally.
To assess this, scientists customarily measure the levels of both the reduced (electrons added) and oxidized (electrons lost) forms of glutathione, a peptide the cell uses as an antioxidant. Glutathione in cells is found predominately in the reduced state, known as GSH, but some gets converted to the oxidized form, known as GSSG. A high amount of GSSG indicates a cell has suffered oxidative stress, a process believed to contribute to cell aging, breakdown, malfunction (such as cancer) and eventual death.
Unfortunately, traditional methods of obtaining this data are akin to an autopsy. The only way to measure the relative amounts of GSH and GSSG within a cell has been to rupture its membranekilling itand then examine the released contents.
The NIST team developed a way to measure GSH and GSSG levels in living cells in real time using nuclear magnetic resonance (NMR)spectroscopy, a technique that images individual molecules similar to how doctors use magnetic resonance imaging (MRI) to noninvasively view organs. "NMR has been shown in recent years to be a powerful tool for studying metabolites as they operate in living cells, so we fel
|Contact: Michael E. Newman|
National Institute of Standards and Technology (NIST)