您现在的位置: Language Tips> Audio & Video> Normal Speed News  
 





 
Aging cells key to slower healing in elderly
[ 2007-08-17 09:08 ]

Download


As we age, our muscles, bones and organs heal more slowly than they did when we were young. And they frequently don't recover to be as strong or resilient as they were before the injury. Researchers say the reason can be found at the cellular level.

Stanford neurology Professor Thomas Rando has been looking at the process of cellular aging and cell injury. One of the things he's found is that adult stem cells play an important part in the healing process. Rando explains that adult stem cells allow tissues to be repaired.


"You cut your skin the skin heals itself. That's because there are stem cells sitting in skin that are continuously generating new skin cells," Rando says. "Without these stem cells, you would run out of blood cells, you would run out of skin cells, you would run out of cells in your gut that are always turning over, and there are stem cells in a lot of other organs as well and tissues, like skeletal muscle, like liver, even some in the brain."

Rando looked at a cell product called Wnt proteins. Researchers used to believe that the presence of Wnt proteins helps stem cells generate healthy new tissue in response to tissue damage. But Rando says that's apparently not all they do.

"What we found surprisingly was that with age it appears as if there are low levels of these Wnt proteins that are continuously acting on stem cells," Rando explains. "And it's something about that continuous activity at a low level that instead of promoting stem cell function, they actually inhibit stem cell function. When the cells are exposed to this environment where there's a lot of this Wnt protein around, they essentially go into a dormant state or a state that is more difficult to get them to begin dividing and making new healthy cells."

Rando says understanding more about the effect of Wnt proteins could lead to new therapies, especially if researchers could find ways to enhance tissue repair by blocking the Wnt protein signals. But he doesn't expect to be able to prevent or reverse aging.

"It's really more in the realm of… if in an older person there is an injury to a tissue, whether it's a skin wound or a broken bone or a muscle injury, can we enhance the repair process?" Rando speculates. "Not to make the old person young but to make the old tissue repair as well as young tissue repairs."

Rando is continuing to study the Wnt proteins to better understand how they function. His research appears in a recent issue of the journal Science.

sleletal muscle : 骨骼肌

点击进入更多VOA常速

(来源:VOA  英语点津姗姗编辑

 

 
 
相关文章 Related Stories
 
         
 
 
 
 
 
         

 

 

 
 

48小时内最热门

     
  打击“盗版书”
  你会说“对不起”吗
  《欲望城市》(精讲十四)
  奥尼尔:姚明的新娘很漂亮
  “吃出来”的惯用语

本频道最新推荐

     
  女孩的心思谁能猜:Suspended from class
  《说点什么吧》:Say something anyway
  Mountain and cowboy culture meet in Jackson Hole
  Livestock disease spreads in Britain
  Working magic in the garden with beans

论坛热贴

     
  索尼出的笔记本电脑vaio怎么读啊
  how to translate 男人味女人味?
  Had I gotten through?
  Beware of plants?
  happy as a mosquito?
  School teaches students to swim by knowing their different strokes(e-c)practice