An antibiotic primarily used in veterinary medicine was found to turn the gut into a factory that pumps out life-extending compounds. The finding could change the way we think about the development of longevity drugs.

The antibiotic tested is called cephaloridine and in the ’60s and ’70s, it was used on humans, where it was an effective ally in fighting off respiratory and urinary tract infections. It is a Beta lactam antibiotic, which is the same as penicillin. The drug works best when administered by injection, as it is not efficiently absorbed in the digestive tract. That, plus the fact that it can cause toxicity that harms the kidneys, caused it to fall out of favor in human use and is now primarily used to treat dogs suffering from staph infections or skin issues.

While it’s no longer a good choice as an antibiotic for people, researchers from the Howard Hughes Medical Institute in Maryland found that it has another potent power. In animal tests, the team demonstrated that the administration of low doses of cephaloridine caused E. coli gut bacteria to begin pumping out colonic acid. This acid is created by gut bacteria as a protective mechanism and previous research from the team has shown it to extend the life of roundworms and fruit flies.

For the new study, the researchers wanted to see if they could use medication to directly influence the production of colonic acid. Indeed, when roundworms in the study were given the antibiotic, they lived up to 30% longer thanks to the increase of colonic acid produced by E. coli in their guts.

The red bacteria in this image represent E. coli that have been reprogrammed to produce colonic acid due to the presence of the antibiotic, cephaloridine

Meng Wang

The team then administered colonic acid produced by E. coli treated with cephaloridine to mice and found that several markers of aging were reduced. The mice had reduced gut permeability, lower systemic inflammation, enhanced mitochondrial function, and lower levels overall of biological aging markers. Male mice also saw an increase in good cholesterol (HDL) and decrease in bad cholesterol (LDL), while female mice experienced a decrease in insulin levels.

One of the benefits of using cephaloridine to reprogram the gut microbiome to produce anti-aging compounds is that the drug itself is poorly absorbed when administered in this way, so it basically passes through the body without much of it entering the blood stream.

That being said, the researchers aren’t calling for the administration of cephaloridine to humans as a life-extension pill – especially taking into account its potentially toxic effects. But they do say that their findings could go a long way to rethinking the way in which we produce drugs, including those that could extend our lives. Instead of developing drugs that directly target the body, they say, we could shift some of our focus to working on drugs that target our gut microbiome, enlisting its help as factories to produce the compounds we need.

That work would build on other efforts that have shown that tweaking the gut microbiome could, among other things, fight multiple sclerosis, improve the effectiveness of cancer immunotherapy treatment, and potentially combat insomnia.

The new study has been published in the journal PLOS Biology.

Source: Howard Hughes Medical Institute via Phys.org