Effects of low-dose oxygen ions and protons on cardiac function and structure in male C57BL/6J mice (echocardiogram/ultrasonography)

Results: Ejection fraction and fractional shortening decreased at 3 and 7 months after 16O. These parameters did not change in mice exposed to γ rays, protons, or protons followed by 16O. Each of the radiation exposures caused only small increases in cleaved caspase3 and numbers of apoptotic nuclei.

Changes in the levels of α smooth muscle cell actin and a 75kDa peptide of collagen type III in the left ventricle suggested tissue remodeling, but there was no significant change in total collagen deposition at 2 weeks, 3 months, and 9 months. Increases in protein amounts of cluster of differentiation (CD)2, CD68, and CD45 as measured with immunoblots at 2 weeks, 3 months, and 9 months after exposure to protons or 16O alone suggested immune cell infiltration.

For type III collagen, CD2 and CD68, the efficacy in inducing protein abundance of CD2, CD68, and CD45 was 16O greater than protons was greater than γ rays greater than protons followed by 16O. Conclusions: Low dose, high energy charged particle irradiation caused mild changes in cardiac function and tissue remodeling in the mouse. This dataset derives result from the cardiac ultrasound and abdominal aorta doppler (echocardiography) assays.