Featured Research

from universities, journals, and other organizations

First Genetic Glimpse Of Aging Kidney Offers Insights Into How Cells Grow Old

Date:
December 13, 2004
Source:
Stanford University Medical Center
Summary:
For the first time, researchers at Stanford University School of Medicine have examined how kidneys change at a molecular level with the passage of time. What they found suggests that all human cells age in a similar way, supporting one theory about how cells grow old.

STANFORD, Calif. – For the first time, researchers at Stanford University School of Medicine have examined how kidneys change at a molecular level with the passage of time. What they found suggests that all human cells age in a similar way, supporting one theory about how cells grow old.

Related Articles


“Until now we really didn’t know what happens when people get old,” said Stuart Kim, PhD, professor of developmental biology and genetics, who led the study that is to be published in the November 30 issue of Public Library of Science Biology. “Our work suggests that there’s a common way for all tissues to get old.”

These findings are contrary to one model for how cells age. This theory holds that because organs have different groups of molecules, they follow different pathways as they age. If this were the case then the aging kidney would look quite different on the molecular level from an aging liver.

Instead the study findings support another model, which suggests that all cells in an animal peter out in the same way. If this were true then researchers would find the same molecular differences between old and young cells from all organs.

In the study, Kim and his group compared which genes are active in kidney cells from 74 people ranging in age from 27 to 92 years. They found 742 genes that become more active as the kidney ages and 243 genes that become less active.

They then did the same experiment using different types of kidney tissue, with one sample from the outer kidney, called the cortex, and the other from the inner kidney, called the medulla. Although these two tissues are both from the kidney, they are as different in function as cells from entirely different organs. The researchers found exactly the same genes varied in old and young samples from these two tissues.

Kim said his study doesn’t suggest what factors drive the aging process, only that once it starts it follows the same path even in different organs. He added that he doubts cells wear out the same way in all animals. The reason is that until the past few centuries humans and other animals usually died before their organs had a chance to grow old, so there’s no reason for evolution to have pushed human, mice and other animal cells to deteriorate in the same way.

“Old people only exist in modern society,” Kim said. “Events that happen when a person is 80 only became common this century.” Likewise, few mice make it to two years old outside the laboratory. Kim is now studying aging mouse kidney cells to test whether they look different on a molecular level than the human kidney cells in this study.

Kim said that whatever happens once aging begins, the mechanism that kicks off the process is probably genetically determined. That’s why humans and mice, whose cells behave almost identically in a lab dish, have such dramatically different life expectancies. “The smallest genetic change can be a big change in terms of lifespan,” he said.

In addition to answering some questions about how cells age, Kim said this work could help screen kidneys used for transplant. In the study, the group found that the molecular age of a kidney matched how well that kidney filtered blood. One sample from an older person had the molecular appearance of a much younger kidney and also filtered blood like a more youthful organ.

This correlation could help screen kidneys from people older than 60 whose organs would ordinarily be rejected for transplants. Kidneys that have a youthful molecular appearance might still function well enough to be transplanted. “We can look at the kidneys that are being thrown out and parse them into those that are physiologically young and physiologically old,” Kim said.


Story Source:

The above story is based on materials provided by Stanford University Medical Center. Note: Materials may be edited for content and length.


Cite This Page:

Stanford University Medical Center. "First Genetic Glimpse Of Aging Kidney Offers Insights Into How Cells Grow Old." ScienceDaily. ScienceDaily, 13 December 2004. <www.sciencedaily.com/releases/2004/12/041206194421.htm>.
Stanford University Medical Center. (2004, December 13). First Genetic Glimpse Of Aging Kidney Offers Insights Into How Cells Grow Old. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2004/12/041206194421.htm
Stanford University Medical Center. "First Genetic Glimpse Of Aging Kidney Offers Insights Into How Cells Grow Old." ScienceDaily. www.sciencedaily.com/releases/2004/12/041206194421.htm (accessed October 23, 2014).

Share This



More Health & Medicine News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola Fears Keep Guinea Hospitals Empty

Ebola Fears Keep Guinea Hospitals Empty

AP (Oct. 23, 2014) Fears of Ebola are keeping doctors and patients alike away from hospitals in the West African nation of Guinea. (Oct. 23) Video provided by AP
Powered by NewsLook.com
Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Working Mother (Oct. 22, 2014) Is your child ready? Video provided by Working Mother
Powered by NewsLook.com
U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

Newsy (Oct. 22, 2014) Now that the U.S. is restricting travel from West Africa, some are dropping questions about a travel ban and instead asking about visa bans. Video provided by Newsy
Powered by NewsLook.com
More People Diagnosed With TB In 2013, But There's Good News

More People Diagnosed With TB In 2013, But There's Good News

Newsy (Oct. 22, 2014) The World Health Organizations says TB numbers rose in 2013, but it's partly due to better detection and more survivors. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins