Radiation from x-rays, even in as low doses such as those required for recurrent CT imaging, could have long-term harmful effects on the cardiovascular system, according to a new study.
While it’s known that high-dose ionizing radiation exposure, be it medical or environmental, can lead to symptoms suggesting an increased risk of cardiovascular disease, the study showed that even low exposure doses are associated with significantly increased risk of cardiovascular damage for up to decades after.
Results from the study were published in the International Journal of Radiation Biology.
Researchers at the German Research Center for Environmental Health aimed to explore how human coronary artery endothelial cells respond to relatively low radiation doses of 0.5 Gy, and found multiple permanent alterations in the cells that could potentially lead to adverse effects, according to the study.
Endothelial cells form the inner layer of blood vessels and were found to produce reduced amounts of the essential molecule nitric oxide during several processes, including vascular contraction. Researchers said that while previous reports have shown decreases in nitric oxide in high-dose radiation mice studies, the study was the 1st to show impaired nitric oxide signaling at low doses.
The exposed cells were also shown to produce increased amounts of reactive oxygen species, which can damage DNA and proteins, according to the study.
Study authors concluded that the molecular changes “are indicative of long-term premature dysfunction and suggest a mechanistic explanation to the epidemiological data showing increased risk of cardiovascular disease after low-dose radiation exposure.”