A recent Brazilian study published in Nature cardiovascular research Has emphasized promising routes for preventing and treating atrial fibrillation, a condition that considerably increases the risks of stroke and dementia. The research was led by the Federal University of Rio de Janeiro (UFRJ) in collaboration with the D’Or Institute for Research and Education (IDOR).
What is atrial fibrillation?
Atrial fibrillation (AF) is the most common cardiac arrhythmias worldwide. It disrupts the normal rhythm of the heart and causes irregular and often fast heartbeats. This condition is associated with increased risks of stroke, dementia and heart failure. It is also linked to other health problems such as hypertension, obesity and sleep apnea, which can worsen its severity.
Although often occurs in older adults who influence about 10% of people who influence more than 80, increase in younger populations, driven by lifestyle changes and chronic stress. Despite the prevalence, the underlying causes of AF are often unclear, making challenges for effective treatment.
When tackling this complexity, the study investigated how chronic inflammation could act as a direct trigger for AF, which releases the road for specific therapies and targeted medicines.
Chronic inflammation and atrium fibrillation
Chronic inflammation is a common denominator in many disorders associated with AF. However, the exact mechanisms that link inflammation to arrhythmia have remained elusive. According to study leader Dr. Emiliano Medi, a researcher at Idor and UFRJ, Interleukine-1 beta (IL-1β) -a molecule of the immune system involved in regulating inflammation, directly influences the electrical activity of the heart, creating a construction for AF AF ,.
Current work marks an important scientific milestone in the field of knowledge. Many assessment papers had already suggested that IL-1β could play a crucial role in atrial fibrillation. We could prove that this actually happens. “
Dr. Emiliano Medi, researcher at Idor and UFRJ
The research team started analyzing the immunological profiles of 92 patients, including 30 healthy controls and 62 people with the diagnosis, all recruited by the Rede d’Or Hospital Network. Their findings offered a solid foundation for further exploration with the help of animal models.
Test atrial fibrillation in mice
To deepen, the researchers used mice to investigate the effects of IL-1β. By administering IL-1β doses for 15 days, they simulated long-term systemic inflammation. During observation, the rodents developed heart changes that made them more susceptible to.
In addition, the team used genetically modified mice without IL-1β receptors in macrophages immune cells found throughout the body, including the heart. These animals did not develop, which showed that IL-1β caused the condition caused by activating its receptors on macrophages.
“In addition to demonstrating that IL-1β is associated with atrial fibrillation, we were able to demonstrate so that the immune system cell works: the macrophages. Certainly, this ‘double discovery’ will contribute to new therapeutic perspectives for these very complex disease,” Dr. Medi notes.
IL-1β as a target for atrial fibrillation therapies
Il-1β as a trigger for AF AF has far-reaching implications. Clinically it is not always possible to determine the specific cause of each patient. Understanding that a single factor, such as IL-1β, plays a role in different scenarios offers a clearer therapeutic target.
The study also opens new roads for treatment. Medications that inhibit IL-1β or Caspase-1-the enzyme that the production of IL-1β activates their promising candidates to prevent from risk patients, in particular with chronic inflammatory disorders.
With an aging world population and the increasing prevalence of disorders associated with AF AF AF his effective prevention and treatment strategies critical priorities for public health. This study offers valuable insights into the connections between the immune system and heart function, with innovative opportunities to tackle.
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Journal Reference:
Moreno-Loaiza, O., et Alt Alto. (2025). IL-1β improves sensitivity to atrium fibrillation in mice by working in through resident macrophages and promoting Caspase-1 expression. Nature cardiovascular research. doi.org/10.1038/s44161-025-00610-8.