The Impact of Gut Bacteria on Blood Vessel Aging and Cardiovascular Health

Recent research from the University of Zurich reveals that our gut microbiome plays a significant role in the aging process of blood vessels, which directly influences cardiovascular health. As we age, the composition of bacteria in our intestines shifts, leading to an increase in harmful substances and a decrease in beneficial metabolites that support vascular integrity.

The inner lining of blood vessels, called the endothelium, is crucial for maintaining vascular flexibility and proper blood flow. Its aging is a key factor in the development of cardiovascular diseases, the leading cause of death worldwide. Even with traditional risk factors such as high blood pressure and diabetes managed, vascular deterioration often persists in older adults.

The study demonstrates that specific bacterial metabolites accelerate vascular aging. One such metabolite, phenylacetic acid—produced when gut bacteria process the amino acid phenylalanine—accumulates with age and causes endothelial cells to become senescent. These senescent cells exhibit decreased proliferation, secrete inflammatory molecules, and contribute to vessel stiffening and impaired function.

The researchers identified the bacterium Clostridium sp. ASF356 as a key player in this process, capable of converting phenylalanine into phenylacetic acid. When young mice were colonized with this bacterium, they showed increased levels of the metabolite and signs of vascular aging; conversely, eliminating the bacteria reduced phenylacetic acid levels.

In addition to harmful metabolites, the gut microbiome also produces beneficial substances like short-chain fatty acids (SCFAs), such as acetate, which act as natural rejuvenators of blood vessels. Experiments show that supplementing with sodium acetate can restore endothelial function in aged cells, highlighting the microbiome’s potential in influencing vascular health.

Diet plays a critical role in modulating this balance. Diets rich in dietary fiber and antioxidants promote the growth of beneficial bacteria that produce rejuvenating SCFAs. In contrast, consuming phenylalanine-rich foods like red meat, dairy products, and certain artificial sweeteners can increase levels of phenylacetic acid, promoting vascular aging.

The researchers are exploring new strategies to reduce harmful bacterial metabolites, including developing medications and genetically modified bacteria to curb phenylacetic acid production. This research underscores the importance of gut health in cardiovascular aging and suggests that dietary and microbial interventions could help preserve vascular function with age.

Source: https://medicalxpress.com/news/2025-05-intestinal-bacteria-aging-blood-vessels.html