Anti-Depression Drug Could Extend Human Life
Scientists in America have highlighted the results of trials in which a drug used to treat depression was observed to extend the lives of minute worms. The scientists, highlighting the significance of their discovery, say that the same drug could also have potential in lengthening human lifespan.
The study - in which 88,000 chemicals were applied one after the other to nematode worms - was described in the publication Nature. During this process, the antidepressant mianserin was seen to extend lifespan by around 30 per cent. The medication seems to replicate the physiological effects of the sole known situation in which animals' lives have stretched beyond the norm - (virtual) starvation.
Human Body Could Have Genes Capable of Extending Life
Medical experts believe that the discovery could indicate the presence of genes within the human body that, if targeted, could act to lengthen life.
It is not fully comprehended why, but, in situations where the body is supplied with only the lowest level of calories required to sustain life, longevity seems to be enhanced.
However, for the majority of humans, such a measure is not viable. Therefore, the research undertaken by the US team - which is based at Seattle's Fred Hutchinson Cancer Research Center - could point to a more practically achievable means of life prolongation.
It may seem that the use of nematode worms in the trials makes them not really comparable to if the same assessments were carried on out humans. However, the worms share a number of characteristics with us, such as a core nervous system.
Furthermore, the worms' inherently short natural lifespan renders them perfect subjects for these kinds of studies.
Antidepressant Helped Worms Live 30 Per Cent Longer
The drug mianserin kept the worms alive for nearly a third longer that they would normally achieve - a situation that could have taken place through the antidepressant's replication of the effects of starvation, as far as the worms' brains were concerned.
"We don't have any explanation for this," said researcher Dr Linda Buck, adding: "All we can say is that if we give the drug to calorific-restricted animals, it doesn't increase their lifespan any further.
"That suggests the same mechanism may be involved."
One possibility, Dr Buck stated, is that the drug upset the usual balance of a pair of chemicals in the brain which assist with deciding if the worms have sufficient levels of food to support the production of eggs. In this instance, she said, a "perceived, but not real" condition of starvation could be generated.
Dr Buck said that the discovery of a chemical capable of prolonging animal life could indicate the presence of human genes that, if targeted, could act in the same way.
"It may be possible to identify additional genes important in ageing", she suggested.
"In addition, the chemical approach could point to drugs suitable for testing in mammals."
Birmingham University's Professor Janet Lord, commenting on the study, said: "What's exciting is that the lifespan extension effects we see extend right across the species, from worms and fruit flies to mammals."
She added: "At the moment, there are interesting experiments in primates which, although the animals involved are only middle-aged so far, suggest that calorific restriction does have an effect on longevity."
Source - Pharmaceutical International's Research and Development Analyst
