How Not to Age: The Scientific Approach to Getting Healthier as You Get Older

by Michael Greger

Intercellular microRNA communication is conserved throughout the evolutionary tree of life, raising the possibility of cross-kingdom gene regulation. In the eighteenth century, life was classified as belonging to either the plant kingdom or the animal kingdom.7171 In the nineteenth century, single-celled organisms like amoebas got their own kingdom,7172 and with further improvements in microscopy, bacteria got one as well. (These days we’re up to seven kingdoms—algae and fungi each got their own, as did bacteria-like organisms originally described as extremophiles, living in previously thought uninhabitable zones like hot springs.7173) With a common language of microRNAs, might inhabitants of different kingdoms communicate with one another? In 2011, we learned that microbiome microRNAs could modulate the gene expression of their host.7174 For example, there are gum disease bacteria that secrete vesicles filled with microRNA shown to penetrate host cells, apparently to suppress our immune response.7175 Sneaky! Then, in 2016, we learned that we have our own microRNA counterinsurgency program.