say they may have found a clue to how to rejuvenate the skin and
slow the ageing process.
Crow's feet: A classic sign of
Wrinkles and the leathery feel of old skin are known
to be linked to a loss of elasticity in the skin tissues.
Now a team from New York's Clarkson University has
found the problem could be down to individual epithelial cells
becoming more rigid with age.
Details, reported in New Scientist, were originally
published in Physics and Medicine in Biology.
have known for a long time that human epithelial tissues lose
elasticity with ageing.
The process is thought to play a role in many
progressive diseases of ageing, including hardening of the arteries,
joint stiffness, cataracts, Alzheimer's and dementia.
However, previous researchers believed the reason
for the loss was only the "glue" that seals the epithelial tissues -
the extra cellular proteins - rather than the cells themselves.
Many treatments of diseases caused by cell
elasticity loss have been based on this assumption.
The Clarkson team has found that after many
generations of cell division, epithelial cells themselves became two
to 10 times as stiff as younger cells.
They found this is due to the cells internal
scaffolding of protein fibres - the cytoskeleton - becoming more
Drugs being tested
The Clarkson team says there are already drugs
available that inhibit the stiffening of the cytoskeleton - and
perhaps slow the ageing process.
They are testing skin creams containing low doses of
these compounds on mice.
First tests have shown rather promising results.
Professor Stuart Parker, of the Sheffield Institute
for Studies on Ageing, told the BBC News website the findings were
technical - and were carried out on cells in culture.
But he added: "The findings put another piece of
knowledge into the jigsaw of our understanding of the cellular and
molecular processes which may be associated with ageing."
Professor Parker said the best way to slow down the
ageing of the skin was to minimise exposure to ultraviolet sunlight.
"The skin is an organ which is exposed to particular
challenges from the environment over a lifetime," he said.
"Damage from ultra violet light is one of the main,
if not the main factor contributing to skin ageing."