Researchers believe the findings that lithium increased lifespan in fruit flies may open the door to an anti-aging drug for humans.
Published in the journal Cell Reports, the study reveals that fruit flies given low-dose lithium lived longer than a control group.
To reach their findings, lead researcher Dr. Jorge Iván Castillo-Quan - who was based at the Institute of Healthy Ageing at the UK's University College London (UCL) at the time of study - and colleagues administered different doses of lithium chloride to 160 adult fruit flies.
The fruit fly, or Drosophila melanogaster, is an ideal model for studying human genetics, as the insects share 75% of the same genes that cause disease in humans.
The team found that when the fruit flies were given low doses of lithium in adulthood or later life, they lived an average of 16-18% longer than flies that received sodium chloride, regardless of the insects' genetic makeup.
The lifespan-increasing effects were strongest with short-term and one-off doses of the drug, according to the researchers; flies that received a single dose of lithium in later life lived an average of 13% longer, while younger flies that were treated with the drug for 15 days before receiving a control drug also had a longer lifespan.
No adverse effects were identified with low doses of lithium, with the team noting that the fruit flies fed normally and produced healthy offspring.
Higher doses of the drug, however, were found to reduce the flies' lifespan.
Lithium blocks GSK-3 to increase lifespan
On investigating how lithium increased the lifespan of fruit flies, the team found the drug blocks activity of a molecule called glycogen synthase kinase-3 (GSK-3).
What is more, the researchers found that, at the same time as blocking GSK-3, lithium promotes activity of a molecule called nuclear factor (erythroid-derived 2)-like 2 (NRF-2), which is involved in protecting cells against oxidative stress - a key player in the aging process.
Based on their findings, the researchers suggest that targeting GSK-3 could be a promising drug target in the fight against aging.
Speaking of the potential implications of these results, Dr. Castillo-Quan says:
"To improve our quality and length of life we must delay the onset of age-related diseases by extending the healthiest period of our lives. Identifying a drug target for aging is a crucial step in achieving this and by targeting GSK-3, we could discover new ways of controlling the aging process in mammals, including humans."
Claire Bale, head of research communications at Parkinson's UK - which helped fund the study - describes the findings as "encouraging," noting that they may bring us closer to strategies that combat age-related diseases.
"This research has the potential to not only help create a healthier older generation, but also provide significant insights into how we could potentially treat or even prevent conditions of aging like Parkinson's," she adds.
According to Prof. Dame Linda Partridge - principal investigator of the study, and director of UCL's Institute of Healthy Ageing and the Max Planck Institute for Biology and Ageing in Germany - says the next step is to target GSK-3 in more complex animals, with the end goal being to develop a drug that can be tested in humans.
Last month, Medical News Today investigated a number of proposed strategies that may one day make reversing the aging process possible.