Table 4.
Murine experiments investigating deep space and its biological impact
| Category | IR type | LET | Dose | Model | Effect | Reference |
|---|---|---|---|---|---|---|
| Altered LV function and structure | 16O | 600 MeV/n | 0.05, 0.1, 0.25, or 1 Gy | C57BL/6J (M) | Reduced LVEF and LVFS at 3 and 7 months post-IR. Increased ɑ-smooth muscle actin and CD2, CD68, and CD45+ cells. No significant difference in apoptosis or fibrosis. | Seawright (2019) |
| 16O | 600 MeV/n | 0.1, or 0.25 Gy | C57BL/6J (F) | No cardiac dysfunction, but noted cardiac remodeling (increased LV mass, EDV, diameter) with an increase in ɑ-smooth muscle actin and CD2+ cells. | Nemec-Bakk (2022) | |
|
GCR 56Fe 16O |
−1 Gev/n 600 MeV/n |
1.5 Gy 0.05, 0.25, or 0.5 Gy 0.15, 0. 25, or 0.5 Gy |
C57BL/6J (M) | GCR decreased cardiac contractility, increased PVR, and altered arterial elastance. | Bishawi (2022) | |
| GCR | 500 MeV/n | 0.5, 1 Gy | C57BL/6J (M) | Acute reduction in global LV systolic function (14, 28 days post-IR) and later at 660 days. Associated with increased expression of markers of fibrosis, inflammation, and hypertrophy. No lower IR threshold determined. | Brojakowska (2023) | |
| GCR | 500 MeV/n | 0.5, 1, 1.5 Gy | ApoE null (M) | Acute reduction in LV systolic function (14, 28 days). No lower IR threshold determined. | Brojakowska (2023) | |
| Altered cardiac transcriptome |
14Si 22Ti |
260 MeV/n 1000 MeV/n |
0.04, 0.08, 0.16 and 0.32 Gy 0.03, 0.065, 0.13, and 0.26 Gy |
CB6F1/Hsd (F) | 12 common DEGs across IR types; 5 of which are involved in circadian rhythms (Arntl, Cry2, Per2, Per3, Bhlhe41) | Garikipati (2021) |
| 56Fe | 1 GeV/n | 0.15 Gy | C57Bl/6NT (M) | Increased expression of genes involved in inflammation, free-radical scavenging, and CV development; activation of TFs TBX5, GATA4, and MEF2C involved in maintaining cardiac homeostasis | Coleman (2015) | |
| Altered cardiac epigenome and metabolome | 16O | 600 MeV/n | 0.1, 0.25, or 1 Gy | C57BL/6J (M) | Acute DNA hypomethylation of retrotransposon LINE-1 14 days post, followed by specific hypermethylation at day 90. At low dose exposures, transsulfuration pathways affected—noted increase in cystathionine levels. | Miousse (2019) |
| 56Fe | 600 MeV/n | 0.5 Gy | C57BL/6J (M) | Dynamic alteration in DNA methylation, repetitive element repression, and expression of methylation-related genes (Dnmt1, Dnmt3a, Uhrf1) | Koturbash (2016) | |
| Prolonged apoptosis and inflammation | 28Si | 300 MeV/n | 0.1, 0.25, or 0.5 Gy | CBA/CaJ (M) | Prolonged elevation in PARP, NFΚB, and proinflammatory cytokines (IL1B, IL-6, TNFα) | Tungjai (2013) |
| Alterations in the peripheral vasculature | 16O |
600 MeV/n 1 GeV/n |
0.5 Gy 0.01–0.25 Gy |
Long Evan rat (M) | Increased abdominal aorta pulsed- wave velocity at 12 months post IR. | Sridharan (2020) |
| 56Fe | 1 GeV/n | 0.5, 1 Gy | Wistar rats (M) | Elevated arterial stiffness in 1 Gy IR rats. Vascular dysfunction mediated by xanthine oxidase and ROS, and diminished endothelial-generated NO in response to Ach | Soucy (2011) |
This table summarizes murine studies investigating aspects of deep space high atomic number and high energy (HZE) particles IR on different aspects of cardiac function and other physiological functions.