Center for Translational Research and Molecular Biology of Cancer, Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology Gliwice Branch, Wybrzeże Armii Krajowej 15, 44-101, Gliwice, Poland.
Silesian University of Technology, Gliwice, Poland.
Strahlenther Onkol. 2018 Mar;194(3):235-242. doi: 10.1007/s00066-017-1220-z. Epub 2017 Oct 23.
Improvement of radiotherapy techniques reduces the exposure of normal tissues to ionizing radiation. However, the risk of radiation-related late effects remains elevated. In the present study, we investigated long-term effects of radiation on heart muscle morphology.
We established a mouse model to study microvascular density (MVD), deposition of collagen fibers, and changes in accumulation of heat shock 70 kDa protein 1 (HSPA1) in irradiated heart tissue. Hearts of C57BL/6 mice received a single dose of X‑ray radiation in the range 0.2-16 Gy. Analyses were performed 20, 40, and 60 weeks after irradiation.
Reduction in MD was revealed as a long-term effect observed 20-60 weeks after irradiation. Moreover, a significant and dose-dependent increase in accumulation of HSPA1, both cytoplasmic and nuclear, was observed in heart tissues collected 20 weeks after irradiation. We also noticed an increase in collagen deposition in hearts treated with higher doses.
This study shows that some changes induced by radiation in the heart tissue, such as reduction in microvessel density, increase in collagen deposition, and accumulation of HSPA1, are observed as long-term effects which might be associated with late radiation cardiotoxicity.
放射治疗技术的改进降低了正常组织受到电离辐射的暴露。然而，与辐射相关的迟发性效应的风险仍然很高。在本研究中，我们研究了辐射对心肌形态的长期影响。
我们建立了一个小鼠模型，以研究受照射心肌组织中的微血管密度（MVD）、胶原纤维沉积以及热休克 70kDa 蛋白 1（HSPA1）积累的变化。C57BL/6 小鼠的心脏接受了 0.2-16Gy 范围内的单次 X 射线照射。在照射后 20、40 和 60 周进行分析。
照射后 20-60 周观察到 MD 减少是一种长期效应。此外，在照射后 20 周收集的心脏组织中，细胞质和核内 HSPA1 的积累显著且呈剂量依赖性增加。我们还注意到，用较高剂量处理的心脏中胶原沉积增加。
这项研究表明，心脏组织中由辐射引起的一些变化，如微血管密度降低、胶原沉积增加和 HSPA1 积累，是作为长期效应观察到的，这些变化可能与迟发性放射性心脏毒性有关。
