A new study provides drug developers with clues on how to extend shelf life without severely restricting calorie intake.
Scientists have known for some time that restricting calorie intake in laboratory animals can prolong their lifespan and reduce their risk of developing old-age diseases, such as cancer, heart disease, diabetes and Alzheimer’s disease.
Some studies suggest that calorie restriction may also have health benefits for humans. However, achieving and maintaining a calorie-restricted diet is a challenge for the vast majority of people.
Therefore, identifying a drug that can mimic the metabolic effects of caloric restriction has been an important objective of life extension research.
Termoneutrality
To identify the chemicals that could contribute to these health benefits, Professor Conti and his colleagues compared the metabolites (metabolism products) of mice housed at 22oC with those living under conditions of 30oC. Researchers fed all mice on a calorie-restricted diet.
At 30oC, the bodies of mice and humans achieve “termoneutrality”. At this point, its internal temperature balances the ambient temperature, making it difficult to reduce body temperature.
Scientists believe that termoneutral conditions reduce some of the health benefits of caloric restriction.
Artificial intelligence
The researchers then used artificial intelligence to identify which of these metabolites were likely to be biologically relevant.
Two metabolites that stood out were nitric oxide, a signaling molecule that dilates blood vessels, and an opioid called encephalin leucine.
In additional experiments in heat-restricted mice, they demonstrated that both chemicals play a role in temperature control.