Featured Research

from universities, journals, and other organizations

MIT Helps Unlock Life-extending Secrets Of Calorie Restriction

Date:
January 1, 2004
Source:
Cold Spring Harbor Laboratory
Summary:
Shedding light on why drastically restricting calorie intake prolongs life span in some organisms, MIT researchers report in the Jan. 1 issue of Genes and Development that lowering the level of a common coenzyme activates an anti-aging gene in yeast.

CAMBRIDGE, Mass. -- Shedding light on why drastically restricting calorie intake prolongs life span in some organisms, MIT researchers report in the Jan. 1 issue of Genes and Development that lowering the level of a common coenzyme activates an anti-aging gene in yeast.

Calorie restriction extends life span in a wide spectrum of organisms, and has been shown to delay the onset or reduce the incidence of many age-related diseases, including cancer and diabetes. No one is sure why it works.

MIT Biology Professor Leonard P. Guarente discovered in 2000 that calorie restriction activates the silenced information regulator (SIR2) gene, which has the apparent ability to slow aging during the low-calorie diet. This gene makes a protein called Sir2, which is normally activated by the coenzyme molecule NAD. Guarente has shown that SIR2 is integrally tied to extending life span in yeast and in the roundworm. Humans carry a similar gene.

This latest study probes how Sir2 is activated by calorie restriction. The authors report that a coenzyme related to NAD, called NADH (nicotinamide adenine dinucleotide) inhibits Sir2 by blocking the action of NAD. During calorie restriction, levels of NADH decline in cells. This decrease in NADH allows NAD to better activate Sir2 and thereby extend life span.

"These findings provide a simple model for activation of Sir2 and extension of life span by calorie restriction," the authors write. "Our findings suggest that the NAD/NADH ratio can serve a critical regulatory function, determining the life span of yeast mother cells. A reduction in this nucleotide activates Sir2 to extend the life span in calorie restriction."

In previous research, Guarente found that rather than a slower metabolism leading to a slower rate of respiration, it turns out that respiration in yeast cells under calorie restriction goes up, not down. "A high respiration rate is intimately connected with calorie restriction in yeast," he said. "A high respiration rate activates SIR2. When respiration goes up, NADH goes down and SIR2 goes up. When SIR2 goes up, longevity happens."

NADH, a coenzyme or enzyme helper, is present in all living cells. (An enzyme is a protein that works like a catalyst in the body to prompt chemical changes; for instance, turning food into energy.) NADH, an activated form of the B vitamin niacin, helps produce energy through a series of chemical reactions in the cell.

In cells, NADH stimulates the production of ATP (adenosine triphosphate), a compound that represents chemical energy in cells. The more NADH a cell has, the more stored energy it has. It remains to be seen whether these findings about yeast and NADH will relate to the extension of life span in mammals by calorie restriction.

In addition to Guarente, authors include Su-Ju Lin, now at the University of California at Davis; Ethan Ford, MIT postdoctoral associate in biology; Marcia Haigis, MIT postdoctoral fellow in biology; and MIT biology graduate student Gregory B. Liszt.

This work is supported by the National Institutes of Health, the Ellison Medical Foundation, the Seaver Institute and the Howard and Linda Stern Fund.


Story Source:

The above story is based on materials provided by Cold Spring Harbor Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

Cold Spring Harbor Laboratory. "MIT Helps Unlock Life-extending Secrets Of Calorie Restriction." ScienceDaily. ScienceDaily, 1 January 2004. <www.sciencedaily.com/releases/2004/01/040101090959.htm>.
Cold Spring Harbor Laboratory. (2004, January 1). MIT Helps Unlock Life-extending Secrets Of Calorie Restriction. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2004/01/040101090959.htm
Cold Spring Harbor Laboratory. "MIT Helps Unlock Life-extending Secrets Of Calorie Restriction." ScienceDaily. www.sciencedaily.com/releases/2004/01/040101090959.htm (accessed July 24, 2014).

Share This




More Health & Medicine News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Newsy (July 24, 2014) Sheik Umar Khan has treated many of the people infected in the Ebola outbreak, and now he's become one of them. Video provided by Newsy
Powered by NewsLook.com
Condemned Man's US Execution Takes Nearly Two Hours

Condemned Man's US Execution Takes Nearly Two Hours

AFP (July 24, 2014) America's death penalty debate raged Thursday after it took nearly two hours for Arizona to execute a prisoner who lost a Supreme Court battle challenging the experimental lethal drug cocktail. Duration: 00:55 Video provided by AFP
Powered by NewsLook.com
Can Watching TV Make You Feel Like A Failure?

Can Watching TV Make You Feel Like A Failure?

Newsy (July 24, 2014) A study by German researchers claims watching TV while you're stressed out can make you feel guilty and like a failure. 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:
from the past week

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