The Burrill Report


One of the reasons early explorers crossed the Atlantic was the lure of a fountain of youth. Ponce de Leon thought he would find it in a place we now know as Florida. But he never did. Instead many people move to Florida, with its endless sunshine and warmth, to live out the last years of their lives.

Now researchers at Milan University in Italy think they may have actually found an elixir that can extend life. When they gave middle-aged mice drinking water laced with a special concoction of amino acids, they lived longer than the average mouse. The key ingredients in the supplemental mixture are so-called branched-chain amino acids, which account for 3 of the 20 amino acids (specifically leucine, isoleucine, and valine) that are the building blocks of proteins.

“This is the first demonstration that an amino acid mixture can increase survival in mice,” says Enzo Nisoli of Milan University in Italy, noting that researchers last year showed that these three amino acids extend the life span of single-celled yeast.

In the new study, published in the October issue of Cell Metabolism, researchers gave middle-aged, male mice extra branched-chain amino acids in their drinking water. The animals were otherwise healthy and eating standard mouse food. Animals that were given the extra amino acids over a period of months lived longer, with a median life span of 869 days compared to 774 days for untreated control animals, an increase of 12 percent.

Those survival gains were accompanied by an increase in mitochondria in cardiac and skeletal muscles. Mitochondria are the cellular components responsible for powering cells. The supplement-fed mice also showed increased activity of SIRT1, a well-known longevity gene, and of the defense system that combats free radicals. Therefore, they showed fewer signs of oxidative damage.

The benefits of the amino acid supplements appear similar to those earlier ascribed to calorie restriction, says Nisoli. Treated animals also showed improvements in their exercise endurance and in motor coordination, the researchers report. All the animals in the current study were male, noted Nisoli, and the researchers plan to test the effects in females in future studies.

The findings in older mice suggest that the supplementary mixture may be specifically beneficial for those who are elderly or ill, rather than for healthy young people or body builders. But it might be a useful preventive strategy--the mice in the study were old but they were not sick.

Nisoli emphasized that consuming amino acid supplements is different from consuming proteins containing those amino acids because they do not have to be digested and can enter the bloodstream immediately, thus requiring no energy loss. He suspects that branched-chain amino acids nutritional supplements may prove to be particularly helpful for people with heart failure, the muscle-wasting condition known as sarcopenia, chronic obstructive pulmonary disease, or other conditions characterized by energy defects. In fact, there are already some small studies in humans to support that idea and branched-chain amino acids supplements are already available for purchase in several countries, including Italy.

The challenge, Nisoli says, will be convincing clinicians that these supplements might be beneficial to their patients. A large clinical trial is needed, but there is little incentive for companies to do such trials for dietary supplements as opposed to drugs, he says. The new work, he notes, supports a “general philosophy of a nutritional approach to disease, aging, and problems of energy status.”


October 08, 2010
http://www.burrillreport.com/article-a_potential_fountain_of_youth.html