Sep 012013


NIH intramural study also shows that individual organs are affected differently

By lowering the expression of a single gene, researchers at the National Institutes of Health have extended the average lifespan of a group of mice by about 20 percent — the equivalent of raising the average human lifespan by 16 years, from 79 to 95. The research team targeted a gene called mTOR, which is involved in metabolism and energy balance, and may be connected with the increased lifespan associated with caloric restriction.

A detailed study of these mice revealed that gene-influenced lifespan extension did not affect every tissue and organ the same way. For example, the mice retained better memory and balance as they aged, but their bones deteriorated more quickly than normal.

This study appears in the Aug. 29 edition of Cell Reports.

“While the high extension in lifespan is noteworthy, this study reinforces an important facet of aging; it is not uniform,” said lead researcher Toren Finkel, M.D., Ph.D., at NIH’s National Heart, Lung, and Blood Institute (NHLBI). “Rather, similar to circadian rhythms, an animal might have several organ-specific aging clocks that generally work together to govern the aging of the whole organism.”

Finkel, who heads the NHLBI’s Laboratory of Molecular Biology in the Division of Intramural Research, noted that these results may help guide therapies for aging-related diseases that target specific organs, like Alzheimer’s. However, further studies in these mice as well as human cells are needed to identify exactly how aging in these different tissues is connected at the molecular level.

The researchers engineered mice that produce about 25 percent of the normal amount of the mTOR protein, or about the minimum needed for survival. The engineered mTOR mice were a bit smaller than average, but they otherwise appeared normal.

The median lifespan for the mTOR mice was 28.0 months for males and 31.5 months for females, compared to 22.9 months and 26.5 months for normal males and females, respectively. The mTOR mice also had a longer maximal lifespan; seven of the eight longest-lived mice in this study were mTOR mice. This lifespan increase is one of the largest observed in mice so far.

While the genetically modified mTOR mice aged better overall, they showed only selective improvement in specific organs. They generally outperformed normal mice of equivalent age in maze and balance tests, indicating better retention of memory and coordination. Older mTOR mice also retained more muscle strength and posture. However, mTOR mice had a greater loss in bone volume as they aged, and they were more susceptible to infections at old age, suggesting a loss of immune function.

Read more . . .


The Latest on: Single gene change
  • Activating a single gene is sufficient to change skin cells into stem cells
    on January 19, 2018 at 5:49 pm

    In a scientific first, researchers have turned skin cells from mice into stem cells by activating a specific gene in the cells using CRISPR technology. The innovative approach offers a potentially simpler technique to produce the valuable cell type and ... […]

  • New gene-editing technique may lead to treatment for thousands of diseases
    on October 25, 2017 at 10:15 am

    Scientists from Harvard University have just unveiled a new gene editor that uses the revolutionary CRISPR-Cas9 technology to target and change a single letter in a string of DNA bases — no cutting necessary. Considering that there are billions of ... […]

  • Single mutation changes a species’ mating
    on August 13, 2016 at 8:00 am

    Once this happens, however, it can create a problem: you can't make major changes ... an essential gene that's critical for neural activity was tweaked in an incredibly subtle and specific way. The new version of the gene changed only a single feature ... […]

  • High anxiety risk in adolescence linked to single gene
    on March 22, 2016 at 4:12 am

    Anxiety disorders often emerge in adolescence, when the brain goes through massive changes and new genes are expressed. Now, researchers have found a gene that may be a factor in the general peak of anxiety during this time. They also found that carrying a ... […]

  • The genetic breakthrough that could change humanity, explained
    on January 15, 2016 at 4:00 pm

    But it is different from traditional forms of gene therapy in one key sense: CRISPR can be used to edit genes on the human germ line, so that those changes are passed down ... scientists could use CRISPR to cure single-gene defects like Huntington's ... […]

  • Single Gene is Linked to Jet Lag and Regulates Sleep and Wake Patterns
    on August 14, 2014 at 4:33 am

    It turns out that there may be one gene connected to jet lag. Scientists have discovered a gene that regulates sleep and wake patterns, which could give ... the light-dark cycles in mice and compared changes in the expressions of thousands of genes in ... […]

  • No Single Gene Responsible for Animal Domestication
    on May 12, 2014 at 5:00 pm

    At last week’s Biology of Genomes meeting here, researchers reported that domesticated rabbits, instead of arising through changes in just one or ... “The message here is that there’s no [single] domestication gene,” says Peter Andolfatto, an ... […]

via Google News and Bing News

Other Interesting Posts

Leave a Reply

%d bloggers like this: