Effects of low-dose oxygen ions on cardiac function and structure in female C57BL/6J mice. (February 2022)

• Record Type: Journal Article
• Authors: Nemec-Bakk, Ashley S.; Sridharan, Vijayalakshmi; Landes, Reid D.; Singh, Preeti; Cao, Maohua; Dominic, Paari; Seawright, John W.; Chancellor, Jeffery C.; Boerma, Marjan
• Is Part Of: Life sciences in space research. Volume 32(2022)
• Page Start: 105
• Page End: 112
• Publication Date: 2022-02
• Subjects: Space radiation -- Mouse model -- Females -- Cardiovascular system -- Degenerative tissue effects; Space biology -- Periodicals; 571.0919
• DOI: 10.1016/j.lssr.2021.12.004
• Languages: English
• ISSNs: 2214-5524

Abstract

Abstract: Purpose: : Astronauts in space vehicles beyond low-Earth orbit will be exposed to high charge and energy (HZE) ions, and there is concern about potential adverse effects on the cardiovascular system. Thus far, most animal studies that assess cardiac effects of HZE particles have included only males. This study assessed the effects of oxygen ions ( 16 O) as a representative ion of the intravehicular radiation environment on the heart of female mice. Materials and methods: : Female C57BL/6 J mice at 6 months of age were exposed to 16 O (600 MeV/n) at 0.25−0.26 Gy/min to a total dose of 0, 0.1, or 0.25 Gy. Cardiac function and abdominal aorta blood velocity were measured with ultrasonography at 3, 5, 7, and 9 months after irradiation. At 2 weeks, 3 months, and 9 months, cardiac tissue was collected to assess collagen deposition and markers of immune cells. Results: : Ultrasonography revealed increased left ventricle mass, diastolic volume and diameter but there was no change in the abdominal aorta. There was no indication of cardiac fibrosis however, a 75 kDa peptide of left ventricular collagen type III and α-smooth muscle cell actin were increased suggesting some remodeling had occurred. Left ventricular protein levels of the T-cell marker CD2 was significantly increased at all time points, while the neutrophil marker myeloperoxidase was decreased at 2 weeks and 9 months. Conclusions: : These results taken together suggest 16 O ion exposure did not result in cardiac fibrosis or cardiac dysfunction in female mice. However, it does appear mild cardiac remodeling occurs in response to HZE radiation.