As you all know, one area of particular interest to me is healthy aging. (After all, we are all getting older! ugh) An interesting article appeared on Medical News Today[i] this past Friday that I thought I’d share. It’s about new research, presented at a London conference on the microbiome last week, on how the diseases associated with aging are intricately tied to the bacterial microbiome.
Dr. Marina Ezcurra, of Queen Mary University in London, used the worm C.elegans (which is commonly used in research on human disease) as a model for aging because it lives only 2-3 weeks and as it ages, believe it or not, it develops pathologies not unlike humans. What is totally fascinating is that the aging of the worm is 100% the result of the aging of its gastrointestinal tract. Thus, it is easy to test what manipulation of various gut bacteria does to increase or decrease the worm’s lifespan…and what diseases may be associated with any particular change.
One body of research out of Baylor College of Medicine, presented by Dr. Ezcurra, involved creating 4,000 different mutant strains of E.coli, each with a specific gene deleted. The C.elegans were then fed these different strains to see what happened. Says the senior researcher on this study, “Of the nearly 4,000 bacterial genes we tested, 29, when deleted, increased the worms’ lifespan. Twelve of these bacterial mutants also protected the worms from tumor growth and accumulation of amyloid-beta, a characteristic of Alzheimer’s disease in humans.” One mutant bacterium overproduced an acid which simulates the mitochondria (the powerhouse of cells), measurably increase the worms’ lives.
Dr. Ezcurra also raised the issue of how metformin, which I have written about several times, increases lifespan. Metformin is known to alter the bacterial microbiome, and in fact, studies on C.elegans have shown that metformin does not work to increase the worms’ lives when they are germ-free and lack gut bacteria. That is, it exerts its anti-aging effects through the microbiota. Apparently, what the drug does is affect bacterial folate metabolism which, in turn, regulates aging.
Dr. Ezcurra’s own research has shown that by colonizing the guts of C.elegans with strains of bacteria previously shown to reduce intestinal aging, she can increase the worms’ lifespans. She will soon be doing experiments colonizing the worms with bacterial strains from humans, the idea being, of course, to narrow down what particular strains of bacteria do, to prevent (or cause) aging and disease.
We already know that we lose microbial diversity as we age. As Dr. Ezcurra said, in her talk, “By better understanding the links between nutrition, microbiome, and health, we can understand how the elderly can maintain their microbiome, and also help them directly by using pre- and probiotic strategies. This would help us age in [a] better way, maintaining health and quality of life in old age without drugs or surgery.”
So yet again, I am left with the conclusion that caring for our biome as we age is going to turn out to be an awfully good idea.