According to you, which is safer for you – the smell of a Big Mac that waters your mouth or the salad that you might buy? The salad? It might not be the case. A recent study revealed that there exists a particular food odor that is responsible for the early death of fruit flies. The findings implies that specific odors, or drugs which block us from sensing them might in fact be helpful in the prevention of diseases and thus extending lives.
It has now been more than ten years since scientists have believed that a diet that is low in calorie tends to lengthen the lives of many organisms, monkeys, fruit flies, yeast and may be human beings as well. However, the link may have as much to do with the smell as it does with the eating. For instance, in the year 2004, Cynthia Kenyon, a molecular geneticist from the University of California in San Francisco, found out that the removal of specific olfactory neurons blocks round worm’s sense of smelling as well as extends their lifespan. Moreover, a few years after, Scott Pletcher, a geneticist from the University of Michigan Medical School along with Gregg Roman, a biologist from the Baylor College of Medicine and their colleagues shortened the life of fruit flies by blowing the smell of live yeast-which is a tasty treat- in the direction of the fruit flies while they were on a diet.
Pletcher and his colleagues were of view that a particular odor was at work, however they did not know which one in question. During that time, other scientists had found a receptor in a group of neurons that allow the fruit flies to smell carbon dioxide. The carbon dioxide is responsible for signalling the presence of a fine meal of tasty yeast.
In order to verify if ever it was the carbon dioxide that was the key to shortening the dieting lives of the fruit flies, Pletcher and Roman got hold of mutant flies that did not have the CO2 receptor. They discovered that the mutant flies were able to live up to 30 percent more than normal flies even when they were put on a standard diet.
Afterwards Pletcher and Roman provoked the neurons that sense carbon dioxide to self-destruct and were confronted with similar life-extending outcomes. Ultimately, when the gene for the CO2 receptor was restored back in the mutant flies, by the researchers, the flies did not enjoy a longer lifespan compared to their normal cousins.
It is noteworthy that the mutant flies that were unable to smell carbon dioxide not only benefited from a long life but they moreover remained resilient and strong by various measures. For instance, according to what the researchers have reported in PLoS Biology, the mutant flies were able to store more fat. This is a crucial to promote a psychological state which helps the flies to fight against stress. Furthermore the number of offspring that the female flies were able to produce was no less than the normal flies.
According to the authors, by blocking the perception of CO2, the animals are tricked to believe that there is no food in the surrounding. As a result, their metabolism is slowed down and they react by conserving their nutritional supplies similarly to the way hungry animals do.
Tadeusz Kawecki, an evolutionary biologist from the University of Lausanne, Switzerland, finds that the result is a very exciting one. He explains that if the physiology and metabolism can be changed by specific odors, then drugs which are capable of blocking certain odros could also changer the physiology and metabolism in human beings. This as a consequence could assist in the preventing diseases or prolonging lives. This idea may seem improbable at this stage; however it definitely works in the case of flies.
Source: Science Magazine
Wed, Jul 7, 2010
Anti Aging, Bioscience, Gerontology, Health And Aging