In ESC Heart Failure, researchers have commented about the correlation between a poor gut microbiome and aging of the heart [1].
The microbiome is important in aging
Research increasingly suggests that the quality and composition of the gut microbiome may play a role as important as exercise on health. The gut microbiome is a living ecosystem that is made up of many types of bacteria, fungi, and other microbes. It plays an important role in health by aiding digestion, regulating the immune system, and supporting many other beneficial processes.
The relationship between the gut microbiome and immune system is a two-way street, with each supporting the other. The immune system ensures that helpful beneficial bacteria thrive while keeping populations of harmful bacteria down.
Unfortunately, as with many things during aging, the immune system goes into decline in a process called immunosenescence. This makes the immune system less able to respond to invading pathogens and maintain the health and diversity of the microbiome.
This is likely one of the reasons why microbiome health also tends to decline with age. Populations of beneficial bacteria dwindle, while harmful, pro-inflammatory bacteria begin to grow in numbers.
The case for the microbiome to influence aging of the heart
The commentary we want to highlight today sees researchers discussing the correlations between the presence and numbers of specific types of gut bacteria and the aging of the heart.
Changes in cardiac structure and function occur with ageing and may lead towards ageing-related cardiovascular disease. Recent explorations into intestinal microbiota have provided important insights into shifts in microbial composition that occur in response to cardiovascular disease pathogenesis. Several proposed mechanisms include altered gut permeability, endotoxemia, and the systemic effect of metabolites including trimethylamine (TMA), short-chain fatty acids (SCFA), and secondary bile acids. However, causal associations between gut microbes and left ventricular (LV) function have yet to be proven. We sought to determine whether gut microbial composition is associated with left ventricular myocardial relaxation, an early manifestation of myocardial ageing, among older adults.
Conclusion
While the size of this study is small, the data is still interesting and suggests that there is at least some correlation between gut microbiome health and heart aging.
The ideal situation would be to run a larger study of this kind to confirm the correlation and potentially look at interventions to address it. A crude but demonstrated way to improve the microbiome is the use of fecal transplantation, in which the microbiome from younger healthy individuals is transferred to older ones. Seeding the aged gut with beneficial bacteria via probiotics may be another approach worth exploring.
One thing is certain: the role of the gut microbiome in aging is becoming increasingly appreciated. Some researchers even suggest that it could be an additional reason why we age, though the jury is still out as to whether it is a cause or a consequence of one of the established aging processes.
Literature
[1] Wong, J. J., Purbojati, R. W., Tan, R. S., Pettersson, S., & Koh, A. S. (2022). Distinct gut microbiota composition among older adults with myocardial ageing. ESC heart failure, 10.1002/ehf2.14139. Advance online publication. https://doi.org/10.1002/ehf2.14139
