Researchers Identify Critical Receptor In Liver Regeneration

[Guest guest]

Source:

University of

California - San Diego

Date:

March 30, 2007

Researchers

Identify Critical Receptor In Liver Regeneration

In studies in mouse models, researchers

at the University of California, San

Diego (UCSD) School of Medicine have

found that a cellular receptor involved in triggering cell death is also a

necessary component of tissue repair and regeneration immediately following

liver injury. This discovery could have implications for early

intervention or therapy in liver disease such as cirrhosis or hepatitis.

In

a report to be published in the March 30 issue of the journal Science, Katerina Akassoglou, Ph.D.

assistant professor in UCSD's Department of

Pharmacology, and colleagues describe the mechanism by which cells associated

with liver damage, called hepatic stellate cells (HSCs), are activated by a cell surface molecule called the

p75 neurotrophin receptor (p75NTR) to promote repair

in the liver.

" Many therapeutics for liver disease target HSCs in order to kill them, but our study in animal models

found that their initial activity could actually be protective, " said Akassoglou.

When

chronic liver injury occurs, cells in the liver begin producing collagen and

other proteins that lead to the formation of fibrous tissue and scarring. Akassoglou's team looked at the

molecular-cellular interface to discover how tissues respond to deposition of

the fibrous protein, fibrin. In studies of a mouse

model with excessive fibrin deposition in the liver, the researchers found that

p75NTR signaling promotes the initial activation of HSC, which stimulates the

proliferation of new hepatic cells to replace those that have been damaged. The effects of p75NTR at late stages of HSC activation and

liver disease remain to be determined.

" We were intrigued by the increase of

p75NTR expression after liver injury and hypothesized that p75NTR might

regulate the progression of liver disease, " said Akassoglou. " By identifying p75NTR as the specific molecular link

between HSCs and liver regeneration, p75NTR could

provide a new therapeutic target for promoting cell regeneration and repair

during chronic liver disease or injury. "

This discovery suggests the importance of

sustaining p75 and early HSC activation -- for example, in the case of liver

transplantation when regeneration of liver cells is critical.

Barb in Texas - Together in the Fight, Whatever it Takes!

Son Ken (32) UC 91 - PSC 99 Listed 7/21 @ Baylor Dallas