Damaged protein could be key to premature ageing

Longevity and liver mitochondrial function in male long-living mice. Credit: Nature Communications, doi:10.1038/ncomms4837

(Medical Xpress)—Scientists have found that the condition of key proteins in the mitochondria -the batteries of cells- could be used to predict, and eventually treat premature ageing. And restricting diet could be one way of making this happen.
The researchers from Newcastle University used interventions, like calorie restriction, a system whereby the cells are deprived of nutrients and which in previous studies has been shown to cause mice to live longer than normal.

These interventions also resulted in more efficient assembly of important mitochondrial proteins into complexes.  In a complex state, proteins work together more effectively, while on their own they generate toxic , which in turn cause cells to age more rapidly. If a similar mechanism is found in people it could lead to treatments, such as new drugs to improve protein assembly. In a paper published today in the journal Nature Communications the team describe their findings.

Ageing process

Thomas von Zglinicki, Professor of Cellular Gerontology at the Institute for Ageing and Health, Newcastle University, said: "Free radicals have long been linked with the . Mitochondria generate the energy required to keep our bodies going but they also generate free radicals. How exactly they are involved in ageing is still controversial. Our data shows that quite minor differences can explain large variations in healthy lifespan. Essentially what we have found is that the ageing process goes slower than normal in mice that managed to form mitochondrial protein complexes more efficiently, and that we actually could help them to do so."

A complex of 96 proteins is at the heart of the mitochondrial power station. Comparing the protein composition in from mice that had more or less propensity to long life, the team found the mitochondria from long-lived animals surprisingly had less of these proteins and thus seemed less well suited for energy production than the shorter-living mice.

However, further research showed that assembly of the protein complex was the key: If individual components were more scarce, assembly was perfect, but became more sloppy if more material was around. This then led to less efficient energy production and more release of , toxic by-products of mitochondrial metabolism.

Calorie restriction could extend lifespan

Dr Satomi Miwa, joint lead researcher on the team and a specialist on mitochondrial function, said: "These data go a long way to explain how can improve , extend lifespan and reduce or postpone many age-associated diseases."

Professor Thomas von Zglinicki added: "We have shown here that complex assembly efficiency correlates to longevity differences in mice that correspond to one or two decades of healthy life in humans. We have also shown that human cells age faster if we corrupt complex assembly. What we now need to do is to see how we can improve the quality of these protein complexes in humans and whether this would extend healthy life."

More information: Low abundance of the matrix arm of complex I in mitochondria predicts longevity in mice. Satomi Miwa, et al. Nature Communications 5, Article number: 3837. DOI: 10.1038/ncomms4837 . Received 24 January 2014 Accepted 09 April 2014 Published 12 May 2014

add to favorites email to friend print save as pdf

Related Stories

New mitochondrial control mechanism discovered

May 04, 2011

Scientists have discovered a new component of mitochondria that plays a key part in their function. The discovery, which is presented in the journal Cell Metabolism, is of potential significance to our understanding of both ...

Mitochondrial process may predict lifespan of organisms

Feb 24, 2014

The complexity in biology is astounding. That is why biologists are thankful that model organisms, like the roundworm Caenorhabditis elegans, can be used to breakdown biological processes into simpler units. ...

The body's power stations can affect aging

May 10, 2011

Mitochondria are the body's energy producers, the power stations inside our cells. Researchers at the University of Gothenburg, Sweden, have now identified a group of mitochondrial proteins, the absence of ...

Recommended for you

New technology allows hair to reflect almost any color

Jul 25, 2014

What if you could alter your hair to reflect any color in the spectrum? What if you could use a flatiron to press a pattern into your new hair color? Those are possibilities suggested by researchers from ...

User comments