New Delhi, June 5: A natural ingredient of milk appears to protect mice indulged with abundant high-fat meals from obesity while keeping them fit and energetic, scientists said today.
Researchers in Switzerland who examined the effects of the milk compound, nicotinamide riboside (NR), said their study on mice may lead to new ways of protecting people from obesity and metabolic disorders as they age.
NR appears to be a new member of the family of vitamin B compounds. The results of the study, carried out at the Swiss Federal Institute of Technology in Lausanne, appeared today in the international research journal Cell Metabolism.
Mice that were given high doses of NR along with high-fat meals burnt more fat and showed, through better running performance, greater endurance in their muscles. But drinking milk alone is unlikely to produce these benefits.
“You need a higher amount (of NR) than what is present in milk,” Johan Auwerx, who led the research and is studying the mechanisms of metabolic disorders, told The Telegraph.
“We propose that (experiencing) the benefits will require taking supplements that are rather easy to synthesise.”
Medical researchers have known for long that nicotinic acid, a member of the vitamin B family, helps lower blood cholesterol. But nicotinic acid has the side effect of severe flushing (marked redness of the face and other areas of the skin), and many people drop treatment.
This side effect is believed to be the result of nicotinic acid tying itself to a receptor, or molecular gateway, called GPR109A on the surfaces of cells.
The study by Auwerx and his colleagues was intended to find alternative ways of producing the benefits of nicotinic acid. Their study shows that NR delivers its benefits without activating the GPR109A receptor.
Their findings suggest that NR enhances the activity of the mitochondria, the powerhouses of the cells, protects mice from metabolic dysfunction and is effective as an oral supplement mixed with food.
Auwerx said future studies should aim at investigating the effect of NR supplementation in humans. “We’re hoping this can be translated into humans, and that (NR) will improve metabolism in humans.”
Their study showed that NR activates a gene for an enzyme called sirtuin, which improves mitochondrial functions. These observations suggest that this new vitamin may be used to “prevent mitochondrial decline that is the hallmark of many diseases with ageing”, the researchers wrote in their paper.
Five years ago, Charles Brenner, a US-based biochemist at Dartmouth Medical School who had first identified NR in milk, too had hinted at a role for the vitamin against ageing ---- through experiments on yeast cells.
Brenner and his colleagues had shown that NR activates an anti-ageing mechanism in yeast that resembles the sirtuin enzyme in humans. The best-known natural sirtuin activator so far has been resveratrol, a compound found in red wine.