A group of scientists and dermatologists are studying the role sweat
glands play in how aging skin recovers from wounds. The goal of the
researchers is to learn more about aging skin and gain insight into how to
better treat and slow the aging process.
The study, published online in the journal Aging Cell (May 17, 2016),
compared the skin of 18 elderly subjects to the skin of 18 young adults,
to determine how each group healed skin lesions. The lesions were
created by the researchers, smaller than the diameter of a pencil eraser
and performed under local anesthesia.
“We’ve identified, for the first time, the cellular mechanisms of altered
skin wound repair in elderly patients,” said first author Laure Rittié, PhD,
research assistant professor in the University of Michigan’s Department
of Dermatology, in a press release.
Beyond the underarm
The researchers had already determined eccrine sweat glands, located
throughout the body, are important for wound closure. The eccrine sweat
glands are major contributors of new cells that replace the cells lost due
to injury. This finding led to a new research question.
“Since we know elderly people tend to sweat less than young adults, we
concentrated on this healing function of sweat glands,” said Dr. Rittié.
In young people, they discovered sweat glands contributed more cells to
wound closure than in aged adults. The cells in aged skin were not as
cohesive, either. Fewer cells participating, spaced further apart, can
create a delay in wound closure and, once repaired, a thinner epidermis in
aged versus young skin.
It was not that the sweat glands were less active in older people, rather,
that the environment in the aging skin had been slowly degraded, making
the skin structures less able to support the new cells that were generated,
noted the press release.
“This tells us that, beyond the frustrating appearance, skin aging also
negatively impacts the ability of the skin to repair itself,” Dr. Rittié
explained.
Clinical implications
The elderly especially would benefit from improved skin healing, and Dr.
Rittié and her team plan to continue the research with that target.
“Limiting skin damage during the aging process is likely to limit the
negative impact of aging on wound repair,” she said. “This study teaches
us that poor wound healing and wrinkling and sagging that occur in aging
skin share similar mechanisms. Chronic sun exposure is an important
factor that damages skin structures that normally support sweat glands.
This is another good reason to wear sunscreen.”