Drug for fresh start
A synthetic molecule seems to re-programme cells to make them more like youthful ones.health and fitness Updated: Feb 02, 2004 19:42 IST
Chemists at the Scripps Research Institute in La Jolla have found a synthetic molecule that seems to re-programme adult cells to make them more like youthful ones. The discovery could provide an easy source of cells to regenerate tissues damaged by disease or injury.
According to a report in Nature, Sheng Ding and colleagues discovered the molecule, which they named reversine. When they treated mouse muscle-forming cells with the drug, the cells apparently reverted to a 'blank' state capable of forming other kinds of tissues. The researchers were then able to guide the cells into becoming bone or fat cells instead.
The cells in our bodies have mostly become specialized or 'differentiated' into one type or another, such as red blood cells or kidney cells. But 'stem cells' haven't yet made their career decision, and so can potentially grow into more than one type of tissue.
Many researchers are working on ways to harvest stem cells from the body and turn them into cell types that could repair damaged tissues. One possible, but ethically controversial, source of stem cells is human embryos.
A handful of others are trying to 'dedifferentiate' adult cells instead - effectively turning back the clock on grown-up cells so they revert into stem cells. This research is inspired by organisms such as the salamander, whose cells can dedifferentiate when it regenerates a lost limb or tail.
The team hit upon reversine by systematically treating mouse muscle cells with some 50,000 different candidate molecules that they hoped might stick to and switch on enzymes capable of producing dedifferentiation. The cells treated with reversine switched off muscle-related genes and no longer gave rise to muscle cells, suggesting that they had dedifferentiated. When plied with particular chemicals, these cells then appeared to form fat or muscle cells.
To make the result more convincing, the team now needs to carefully document the muscle cells regressing into a stem-cell-like state, says Mark Keating from Harvard Medical School in Boston, Massachusetts. "They must also work out which enzymes reversine interferes with, and whether this might cause problems in the human body".