Navigation Links
Vitamin Extends Life in Yeast, Dartmouth Medical School Researchers Find

Hanover, NH--Imagine taking a vitamin for longevity! Not yet, but a Dartmouth discovery that a cousin of niacin prolongs lifespan in yeast brings// the tantalizing possibility a step closer.

The research, reported in the May 4 issue of Cell, shows how a new vitamin extends lifespan in yeast cells, much like calorie restriction does in animals. It could pave the way for developing supplements to benefit humans.

Radical calorie reduction can extend life. Dieting or fasting mice live longer and lowering the glucose that yeast grow on extends their lifespan, according to Dr. Charles Brenner, associate professor of genetics and of biochemistry, who led the research.

“If we could do this in humans -- give people a drug or vitamin that would mimic effects of calorie restriction without having to skip lunch -- we would be able to provide some of the benefits of calorie restriction, which are pretty striking in model organisms,” said Brenner, also a member of the Norris Cotton Cancer Center at Dartmouth-Hitchcock Medical Center.

Many benefits, explains Brenner, depend on a family of proteins called sirtuins—dubbed anti-aging gene products for the important roles they play in longevity and energy expenditure, although the precise mechanisms are still being figured out.

His team found that providing a newly discovered vitamin activates the yeast anti-aging gene product Sir2, which resembles sirtuins found in humans. The new work builds on Brenner’s prior discovery of the vitamin, termed NR (nicotinamide riboside), a natural product found in milk. Like the B3 vitamin, niacin, NR is a precursor to a versatile cellular factor that is vital for all life.

The factor, called NAD, short for nicotinamide adenine dinucleotide, is elevated by calorie restriction. So the researchers set out to develop an intervention to elevate NAD, using yeast cells, whose genes are easy to manipulate. “It’s surprising that no one w as be able to elevate NAD with a small molecule before,” Brenner said.

The team discovered two pathways that allow yeast to raise NAD levels with NR, improve their control of gene expression and live longer in the presence of high glucose. One of the pathways is new; the other was previously identified by Brenner’s lab.

At the molecular level, elevating NAD to turn on Sir2 actually enables the yeast to silence genes that are not supposed to be expressed. In any organism, not all genes are on at once; in yeast, there are sets of genes that Sir2 normally represses.

”We showed that that we could improve Sir2-dependent gene silencing with NR and increase the longevity of yeast grown in high glucose conditions,” Brenner said.

To test for Sir2 gene repression, the investigators found conditions in which wild-type cells can’t accomplish normal gene silencing. Then, when they take up NR through one of the pathways Brenner’s team discovered, Sir2 gene silencing is restored, and yeast are rejuvenated. Yeast cells formerly capable of dividing 13 times, divided over 23 times when given NR.

Deletion of either pathway makes NR only half as effective as it is when both pathways are intact. So yeast cells seem to use both pathways equally well to lengthen their lifespan. The first NR pathway, described in 2004, consists of a gene common to yeast and humans. In fact, that gene is activated in damaged neurons in order to allow NR to protect against loss of axons. The second NR pathway involves three yeast genes, two of which are found in humans.

Granted that the human anti-aging apparatus is more complex, but animal studies indicate potential. Perhaps the best known sirtuin activator is the red wine compound resveratrol. Overfed mice on high dose resveratrol have healthier livers, better endurance and possibly longer lifespan. While resveratrol and NR work through different mechanisms to increase sirtuin activity , Brenner said, “the two compounds could be complementary or synergistic.”

More testing remains for NR in humans, but Brenner foresees intriguing possibilities. “As a natural product found in milk, we expect the compound to be much safer than most drugs, and to be a more specific remedy than most vitamins.”

Though aging itself is not a disease, Brenner anticipates applications in conditions associated with aging including neurodegenerative diseases, metabolic syndrome, and elevating good cholesterol. There are also indications that NR could be a treatment for one type of Candida infection.

Source-Eurealert
MED/B
'"/>




Related medicine news :

1. Vitamin B12 can help in detecting cancers
2. Vitamins-The answer to Heart Disease?
3. Vitamin E, the latest warrior against diabetes
4. Vitamin Shields Brittle Bones
5. B Vitamin protects and lowers toxicity of Arthritis Drug
6. B Vitamin Supplementatoin Saves Money and Lives
7. Eat Vitamin C and stay young
8. Vitamin C for the heart
9. Vitamin B for Hepatitis
10. Vitamins reduce pre-eclampsia
11. Vitamin E useful for Alzheimers
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:8/20/2017)... , ... August 20, 2017 , ... ... HIPAA ComplyPAK™ Compliance Management System has assisted multiple clients in successfully ... Public Accountants, Service Organization Control Level 2 (AICPA SOC Level 2), and State ...
(Date:8/19/2017)... ... August 19, 2017 , ... ... will feature the Aurum Group in an upcoming episode, slated to air fourth ... Innovations will feature the Aurum Group; a company committed to supporting dentistry using ...
(Date:8/19/2017)... ... August 18, 2017 , ... ... Act of 2017, legislation that provides for greater public access to over-the-counter (OTC) ... loss to access OTC hearing aids without being seen by a certified and ...
(Date:8/19/2017)... ... August 19, 2017 , ... Praeclarus Press has launched a ... show the diversity of the breastfeeding mothers, using bright colors and contemporary ... These illustrations are also available on tote bags, notepads, smartphone cases, clocks, and ...
(Date:8/19/2017)... ... August 19, 2017 , ... Physician ... its Orlando location as an interventional pain management physician. He brings a wealth ... treatment of migraine headaches, and significant experience in spinal cord stimulation for chronic ...
Breaking Medicine News(10 mins):
(Date:8/7/2017)... Aug. 7, 2017 Diplomat Pharmacy, Inc. (NYSE: ... Saban as president, effective Aug. 7, 2017. ... decided to pursue other interests and will serve as president ... Paul has served us in multiple leadership roles since he ... Jun. 2015 and has provided decisive, strategic leadership which continues ...
(Date:8/7/2017)... 2017  Endo International plc (NASDAQ: ENDP ... virtually all known U.S. mesh product liability claims and ... known remaining U.S. claims at reasonable values. Under the ... fourth quarter of 2017 and continuing through the fourth ... 2017 results, the Company intends to increase its mesh ...
(Date:8/4/2017)... CINCINNATI , Aug. 3, 2017  Agragen, ... science company active in the biopharmaceutical, nutraceutical, and ... its development of its lead drug candidates, AGR131.  ... a proinflammatory cytokine from the blood of patients ... psoriasis, and inflammatory bowel disease. ...
Breaking Medicine Technology: