Researchers discover mechanism that limits scar formation

Jun 10, 2010

Researchers from the University of Illinois at Chicago have discovered that an unexpected cellular response plays an important role in breaking down and inhibiting the formation of excess scar tissue in wound healing.

Their study was published online this week in .

When an organism suffers severe injury, specialized cells are "recruited" to the wound site that rapidly produce such as collagen to provide structural support to the tissue, according to Lester Lau, professor of biochemistry and molecular biology at the UIC College of Medicine and principal investigator in the study.

Joon-Il Jun, a postdoctoral fellow working in Lau's lab and first author of the paper, found that recruited to the site of skin were entering a state of reproductive dormancy, or cell-cycle arrest, called senescence.

This was quite unexpected, Jun said. Until now senescence was believed to occur in cells that suffered -- to prevent them from proliferating and, possibly, becoming cancerous.

He discovered that the senescent fibroblasts were making proteins that degraded the extracellular matrix and accelerated the breakdown of collagen. The senescent cells also stopped making collagen.

"The accumulation of in the wound has the biological effect of inhibiting the formation of excess ," Jun said.

Jun also discovered that a protein called CCN1 is responsible for turning on the senescent state in fibroblasts. He was able to show that in mice with a mutated, non-functional form of CCN1, the fibroblasts at the site of a skin wound did not become senescent, and the wound developed excessive scar tissue.

Further, Jun was able to "rescue" the mutated mice by applying CCN1 protein topically to the skin wound, triggering fibroblast senescence and limiting the formation of scar tissue.

The discovery that senescence is a normal wound-healing response in the skin; that senescence in the wound serves an anti-fibrotic function; and that CCN1 is the critical protein that controls this process may prove important in understanding a wide range of pathological conditions related to tissue scarring, said Lau.

"For example, chronic injury to the liver from a number of causes, including viral infections, alcoholism, diabetes and obesity, leads to fibrosis and may progress to cirrhosis," Lau said. "After a heart attack, accumulation of scar tissue in the heart impairs its ability to pump efficiently."

The ability to control the formation of scar tissue, or fibrosis, has important implications for future therapies for treating wound-healing disorders, including organ damage where functional tissue is replaced with scar tissue, Lau said.

Explore further: Microscopic rowing—without a cox

Related Stories

Skin care: new research into scar-free healing

Jan 21, 2008

New research from the University of Bristol shows that by suppressing one of the genes that normally switches on in wound cells, wounds can heal faster and reduce scarring. This has major implications not ...

Artificial skin system can heal wounds

Dec 20, 2007

A new study in Artificial Organs tested the effects of a wound dressing created with hair follicular cells. The findings reveal that skin substitutes using living hair cells can increase wound healing.

Recommended for you

Researchers uncover secrets of internal cell fine-tuning

47 minutes ago

New research from scientists at the University of Kent has shown for the first time how the structures inside cells are regulated – a breakthrough that could have a major impact on cancer therapy development.

Microscopic rowing—without a cox

1 hour ago

Many different types of cell, including sperm, bacteria and algae, propel themselves using whip-like appendages known as flagella. These protrusions, about one-hundredth of a millimetre long, function like ...

Illuminating the dark side of the genome

7 hours ago

Almost 50 percent of our genome is made up of highly repetitive DNA, which makes it very difficult to be analysed. In fact, repeats are discarded in most genome-wide studies and thus, insights into this part ...

User comments : 0