The gut microbiome undergoes changes with age, negatively impacting health by increasing pro-inflammatory microbes and decreasing beneficial populations. Researchers explore how an aged gut microbiome contributes to cardiovascular disease, highlighting the risk of arrhythmia in mice. The mechanism involves increased oxidative stress from microbial activities, disrupting heart metabolism. The prevalence of arrhythmias, particularly atrial fibrillation and ventricular tachyarrhythmias, rises with age. Gut microbiota plays a crucial role in cardiovascular diseases, influencing host immunity and metabolic balance. Studies show changes in microbial composition in patients with atrial fibrillation, with implications for arrhythmia susceptibility. In aged mice, fecal microbiota transplantation increased arrhythmia risk, linked to intestinal reactive oxygen species affecting ion channel proteins. Gut microbiota depletion reduced oxidative stress and arrhythmia in aged mice. Interestingly, oxidative stress induced by hydrogen peroxide also increased arrhythmia susceptibility. Transplantation of aged gut microbiota metabolites induced oxidative stress in young mice. Overall, the study demonstrates how an aged gut microbiome reduces cardiac ion channel protein expression through systemic oxidative stress, leading to an increased risk of arrhythmias.
Link: https://doi.org/10.1016/j.isci.2024.110888
