“It’s exciting to think that we are one step closer to understanding what happens as the brain ages, and how a change of brain metabolism may be important during the onset of age-related changes and diseases”, says Professor Lars Olson, who lead the study.

The research group used both prematurely and normally aging mice to investigate the relationship between damage to mitochondria — the organelle responsible for energy production in the cell — and changes in metabolism during the aging process. Previous studies have shown a link between mitochondrial dysfunction and age-related neurodegenerative disorders, such as Parkinson’s and Alzheimer´s disease.

In the current study, which is published in the Proceedings of the National Academy of Sciences, the researchers show that the damage to the mitochondria slowly increases with age in brains of mice and causes altered expression in certain genes that are responsible for the formation of lactate. They also show that brain lactate levels may increase in advance of other indices of aging, and can be detected using non-invasive magnetic resonance imaging techniques.

“Our study was conducted in mice, but the same technique can be used in humans”, says Lars Olson. “So there is hope that one day physicians might be able to give your brain a check-up and help determine its age by using MRI.”

In addition to Lars Olson’s research group at Karolinska Institutet, scientists from the US, Germany and the UK took part in the study. The group will now continue its search for new knowledge, trying to understand the role of high lactate in the brain.

Publication: ‘High brain lactate is a hallmark of aging and caused by a shift in the lactate dehydrogenase A/B ratio’, Jaime M. Ross, Johanna Öberg, Stefan Brené, Giuseppe Coppotelli, Mugen Terzioglu, Karin Pernold, Michel Goiny, Rouslan Sitnikov, Jan Kehr, Aleksandra Trifunovic, Nils-Göran Larsson, Barry J. Hoffer & Lars Olson, Proceedings of the National Academy of Sciences (PNAS) Online Early Edition 1-5 November 2010.

For further information, please contact:

Lars Olson, Professor
Department of Neuroscience
Mobile: +46(0)70-670 33 88
E-mail: lars.olson@ki.se

Jaime M. Ross, Doctoral Student
Department of Neuroscience
Tel: +46(0)8-524 87051
Mobile: +46 (0)73-677 63 95
E-mail: Jaime.Ross@ki.se or rossja@nida.nih.gov

Karolinska Institutet is one of the world’s leading medical universities. Its mission is to contribute to the improvement of human health through research and education. Karolinska Institutet accounts for over 40 per cent of the medical academic research conducted in Sweden, and offers the country’s broadest range of education in medicine and health sciences. Since 1901 the Nobel Assembly at Karolinska Institutet has selected the Nobel laureates in Physiology or Medicine. More information on ki.se.

CAPTION: Lars Olson, photo by Camilla Svensk