New Delhi, June 21 : For decades, the scientific community has pursued methods to prolong human lifespan. While extensive research on select laboratory animals demonstrates that caloric restriction can extend their lives, direct human application of such findings has been limited. A foundational century-old study on rodents revealed that mice consuming fewer calories consistently outlived their well-fed counterparts. However, adhering to a perpetual, restrictive diet presents significant challenges for most individuals.
Intriguingly, a recent study from the University of East Anglia’s School of Biological Sciences proposes that a combination of FDA-approved medications, designed to replicate the effects of dietary restriction, might offer a viable path to increased longevity. The two drugs in question, Rapamycin and Metformin, are already recognized for their ability to extend the lifespan of mice by up to 30%.
Rapamycin, initially discovered in the 1970s from bacteria found in Easter Island soil, has traditionally served as a potent immunosuppressant to prevent organ transplant rejection. Its mechanism involves deactivating a cellular switch that signals an abundance of nutrients. Metformin, a synthetic compound derived from French Lilac or Goat’s Rue, is commonly prescribed to manage blood sugar levels in individuals with Type 2 diabetes.
Given that both drugs influence the body’s nutrient and energy sensing pathways, biologists sought to investigate whether their combined use could replicate the longevity benefits observed with caloric restriction. To this end, scientists meticulously reviewed thousands of existing studies, ultimately focusing on 167 investigations across eight vertebrate species, including fish and monkeys. This extensive analysis provided crucial insights into the drugs’ effects on various animals.
Among the three primary strategies for promoting longevity—caloric restriction, Rapamycin administration, and Metformin consumption—scientists concluded that eating less remains the most reliable method for increasing lifespan, irrespective of the animal’s sex. They further noted that Rapamycin was the second most effective strategy, while Metformin showed no substantial impact. However, it’s important to acknowledge the inconsistent effects of Rapamycin; in some instances, studies indicated that both caloric restriction and Rapamycin actually reduced an animal’s lifespan.
Crucially, most of these positive outcomes were observed in mice and rats, whose genetic makeup, while similar to humans, is not identical. Furthermore, Rapamycin is associated with side effects, such as reduced immunity. Consequently, researchers are now exploring whether lower doses of the drug can provide longevity advantages without undesirable side effects.
An ongoing human trial investigating Rapamycin suggests that lower dosages might indeed contribute to increased lifespan. Nevertheless, this trial is still in progress, and definitive results are anticipated in several years.
