Researchers from Tufts University School of Medicine and Tufts Graduate School of Biomedical Sciences aimed to investigate the immune system’s role in doxorubicin-induced heart damage. The study found that doxorubicin can damage the heart by creating harmful molecules called reactive oxygen species (ROS). These molecules trigger inflammation, involving immune cells such as CD4+ and CD8+ T cells.
Normally, these cells defend the body against infections and tumors. However, researchers discovered that doxorubicin can cause these defenders to attack the heart. Experiments on mice showed that doxorubicin treatment increased CD8+ T cells in the heart.
CD8+ T cells produce inflammatory substances that cause heart tissue damage and scarring, decreasing the heart’s ability to pump blood effectively. When the researchers removed the CD8+ T cells from the mice, the heart damage and scarring were significantly reduced. This immune response was not limited to mice.
The study also included observations from dogs and humans. Both groups showed increased levels of CD8+ T cells after receiving doxorubicin, linking the drug to immune-triggered heart damage across different species. “Our study is the first to show that a specific cell type can cause chronic inflammation in the heart after doxorubicin treatment and the first time T-cells have been implicated in this disease,” study author Abe Bayer, a student in the Tufts M.
D./Ph.D.
immunology program, said in a press release. The researchers admit that they don’t know why the drug causes T-cells to attack the heart, but they plan to study it in the future. The review indicates that both naturally aged hearts and those affected by doxorubicin struggle with pumping blood efficiently.
This condition, known as diastolic dysfunction, occurs when the heart doesn’t fill with blood properly between beats. The npj Aging review also showed significant structural changes in aged hearts and those affected by doxorubicin. These changes include heart hypertrophy, a condition in which the heart muscle thickens, and causes an accumulation of waste products in heart cells, hindering proper function.
As the number of cancer survivors increases, it’s crucial to ensure treatments don’t cause lingering side effects, particularly to the heart, according to Dr. Nicolas Palaskas, a cardiologist at MD Anderson Cancer Center. Heart damage from cancer treatment is relatively uncommon, said Dr.
Palaskas. “Keep in mind that heart damage stemming from cancer treatment is still pretty rare. In fact, only about 5% of my cardiology patients have heart problems related to cancer treatment.
” Specifically, about 2 percent of breast cancer patients and up to 5 percent of lymphoma and sarcoma patients experience heart-related side effects from doxorubicin. Dr. Goodyear emphasizes the critical need for individualized screening before starting doxorubicin treatment.
He highlights the importance of an echocardiogram and thorough cardiac evaluations, especially in the context of potential myocardial injury linked to COVID-19 vaccinations. Dr. Goodyear also stresses monitoring the total lifetime exposure to doxorubicin, noting that the U.
S. Food and Drug Administration advises keeping the cumulative dose within 450–50 mg/m2 of body surface area to minimize risks. Patients should watch for symptoms of heart failure or blockages, including chest pain, shortness of breath, leg swelling, and the need to sleep at an angle.
Immediate medical attention can lead to timely interventions. Stay active: Engage in 150 minutes of moderate or 75 minutes of vigorous physical activity weekly. Maintain a healthy weight: Losing 5–10 percent of body weight if overweight offers substantial health benefits.
Follow a healthy diet: Adopt a Mediterranean-style or mostly plant-based diet limited in sugar..
