Ibuprofen can banish headaches and soothe throbbing joints, but the drug may have another benefit, reports Science Mag. A new study shows that it increases longevity in lab organisms, raising the possibility it does the same thing in people.
To put ibuprofen through its paces, biochemist Michael Polymenis of Texas A&M University, College Station, and colleagues gave yeast, nematode worms, and fruit flies doses of the drug that are comparable to what humans would take. The life spans of all three types of organisms increased if they received ibuprofen, the researchers report. In yeast, for instance, ibuprofen stretched life span by 17%, half of what researchers can produce by cutting the cells’ food supply (another approach to increasing longevity). Worms survived about 10% longer on the drug, and flies gained about the same amount.
But it’s not obvious why ibuprofen would benefit these organisms. The drug stems inflammation in people by blocking cyclooxygenase enzymes, which help synthesise inflammation-promoting molecules. Yeast and nematodes don’t have these enzymes, however, and they don’t suffer from inflammation.
A clue may come from a previous study that showed the drug poisons yeast that can’t make the amino acid tryptophan, which cells need to manufacture proteins. Polymenis and colleagues found that tryptophan levels declined in yeast cells exposed to ibuprofen. They also showed that the drug spurs destruction of a protein that enables cells to absorb tryptophan.
Ibuprofen doesn't have a huge impact on tryptophan levels, though, decreasing them by about 15% to 20% in the yeast. To explain how this modest drop in tryptophan concentration promotes longevity, the researchers invoked a counter-intuitive mechanism. Numerous studies have found that instead of killing organisms, moderate amounts of stress – such as intermediate doses of radiation or toxic chemicals – actually increase life span. A mild tryptophan deficiency triggered by ibuprofen might work in the same way, the researchers speculate. "We figure it’s one more type of stress that seems to be conducive to life span," Polymenis says.
[link url="http://news.sciencemag.org/biology/2014/12/ibuprofen-boosts-some-organisms-life-spans"]Full Science Mag report[/link]
[link url="http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1004860"]PLOS Genetics abstract[/link]