Navigation Links
Researchers extend mouse lifespan by protecting against free radicals

Scientists at the University of Washington and their colleagues at other research centers have found a way to significantly extend the lifespan of mice while reducing the impact of the aging process. Their study, which will be published online by the journal Science on May 5, lends more credence to the free-radical theory of aging.

The theory suggests that very reactive chemicals, called "free radicals," can be damaging to the body at the cellular level. Those reactive chemicals can take part in unnecessary chemical reactions that can damage the cell components, including DNA. Some researchers believe that free radicals could contribute to or hasten heart disease, cancer, and other age-related diseases. The theory also suggests that if the body could be protected from those free radicals, then age-related diseases could be tamed and organisms ?and ultimately people ?may be able to live longer.

Scientists have previously been able to extend the lifespan of mice in lab experiments by managing their diets and reducing their caloric intake. Another method relied on the restriction of a growth factor, but a side effect was that the mice suffered from dwarfism. However, neither of those methods of elongating the mouse lifespan was clearly connected to the free-radical theory of aging.

A group of scientists led by Dr. Peter Rabinovitch, professor of pathology at the UW School of Medicine, examined a method that was closely connected to the free-radical theory. He and his colleagues focused their study on catalase, an enzyme in the body that helps convert hydrogen peroxide into water and oxygen. Hydrogen peroxide is a waste product of metabolism and it can be a the precursor of free radicals that can damage the cell. The damage can in turn lead to more flaws in the cell's chemical processes, making a vicious cycle that leads to more free radicals, more cellular damage, and so on.

The researchers studied mice with a genetic variation that made them produce more human catalase, the enzyme that breaks down hydrogen peroxide. They targeted delivery of the catalase to different areas of the cell: the cytoplasm, where catalase normally goes to decompose hydrogen peroxide; the nucleus, the DNA-containing "control center" for the cell; and the mitochondrion, the cell's power plant that converts organic matter into energy.

They compared the different groups of mice to a control group and found that increased production of catalase could affect the mouse lifespan. The mice with higher catalase levels in the mitochondria, dubbed the MCAT group, had about a 20 percent increase in average and maximum lifespan, or about four and a half months. The mice with increased catalase levels in the nucleus and cytoplasm saw only modest increases in lifespan. These results fit with the theory that mitochondria can be an important source of free radicals created as a byproduct of energy production. Removing hydrogen peroxide "at the source" seems to be the most effective strategy for enhancing lifespan, Rabinovitch said.

The scientists also found that the mitochondrion-targeted catalase mice had healthier heart muscle tissue, indicating that the catalase helped protect from age-related heart problems seen in wild-type mice. The MCAT mitochondria also had fewer mutations, and the MCAT nuclear DNA had fewer oxidized components.

"This study is very supportive of the free-radical theory of aging," said Rabinovitch. "It shows the significance of free radicals, and of reactive oxygen species in particular, in the aging process."

This study and others that are able to extend animal lifespan beyond the normal limits are very powerful in that they most clearly demonstrate the important steps and pathways in the aging process, Rabinovitch said. By identifying these steps and pathways, scientists could pave the way for future development of drugs or other treatments that protect the body from free radicals a nd possibly some age-related conditions.

"People used to only focus on specific age-related diseases, because it was believed that the aging process itself could not be affected," Rabinovitch explained. "What we're realizing now is that by intervening in the underlying aging process, we may be able to produce very significant increases in 'healthspan,' or healthy lifespan."


'"/>

Source:University of Washington


Related biology news :

1. Researchers discover way to make cells in the eye sensitive to light
2. Researchers find how protein allows insects to detect and respond to pheromones
3. Researchers Uncover Key Step In Manufacture of Memory Protein
4. Researchers reveal the infectious impact of salmon farms on wild salmon
5. Researchers identify target for cancer drugs
6. Researchers discover molecule that causes secondary stroke
7. Researchers find missing genes of ancient organism
8. Researchers trace evolution to relatively simple genetic changes
9. Researchers add new tool to tumor-treatment arsenal
10. UF Researchers Map Bacterial Proteins That Cause Tooth Loss
11. VCU Researchers Identify Networks Of Genes Responding To Alcohol In The Brain
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/11/2017)... , April 11, 2017 No two ... researchers at the New York University Tandon School ... Engineering have found that partial similarities between prints ... used in mobile phones and other electronic devices ... The vulnerability lies in the fact that ...
(Date:4/5/2017)... April 4, 2017 KEY FINDINGS ... expand at a CAGR of 25.76% during the forecast ... the primary factor for the growth of the stem ... https://www.reportbuyer.com/product/4807905/ MARKET INSIGHTS The global stem cell ... application, and geography. The stem cell market of the ...
(Date:3/30/2017)... 2017 Trends, opportunities and forecast in this ... technology (fingerprint, AFIS, iris recognition, facial recognition, hand geometry, ... end use industry (government and law enforcement, commercial and ... and others), and by region ( North America ... Asia Pacific , and the Rest of the ...
Breaking Biology News(10 mins):
(Date:10/9/2017)... Arizona (PRWEB) , ... October 09, 2017 , ... ... Kindred, a four-tiered line of medical marijuana products targeting the needs of consumers ... and packaging of Kindred takes place in Phoenix, Arizona. , As operators of ...
(Date:10/7/2017)... (PRWEB) , ... October 06, ... ... years’ experience providing advanced instruments and applications consulting for microscopy and surface ... expertise in application consulting, Nanoscience Analytical offers a broad range of contract ...
(Date:10/7/2017)... WALTHAM, Mass. , Oct. 6, 2017 /PRNewswire/ ... pioneering work of three scientists, Jacques Dubochet, ... whose breakthrough developments in cryo-electron microscopy ... this technology within the structural biology community. The ... Scientific. Scientists can now routinely produce highly resolved, ...
(Date:10/6/2017)... ... October 06, 2017 , ... ... lunch discussion and webinar on INSIGhT, the first-ever adaptive clinical trial for glioblastoma ... Cancer Institute. The event is free and open to the public, but registration ...
Breaking Biology Technology: