MRI Study on the Changes of Bone Marrow Microvascular Permeability and Fat Content after Total-Body X-Ray Irradiation

作者：Wang, Kejun; Zha, Yunfei^*; Lei, Hao; Xu, Xiao

来源：Radiation Research, 2018, 189(2): 205-212.

DOI：10.1667/RR14865.1

• CONTRAST-ENHANCED MRI
• ENDOTHELIAL PROGENITOR CELLS
• NUCLEAR-MAGNETIC-RESONANCE
• ACID-COMPOSITION
• PROTON NMR
• STEM-CELLS
• ATHEROSCLEROSIS
• MODEL
• DISEASE
• MICROENVIRONMENT

In this study, we investigated microvascular perfusion status, changes to fat content and fatty acid composition in the bone marrow of rat femurs after total-body irradiation by quantitative permeability parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and ex vivo high-resolution magic angle spinning (HRMAS) H-1 nuclear magnetic resonance spectroscopy (NMRS). Thirty-six Sprague-Dawley rats were randomly assigned to either an irradiated or nonirradiated control group. Permeability imaging using DCE-MRI and HRMAS 1H NMRS was performed before irradiation, as well as at days 4 and 7 postirradiation. The volume transfer constant (K-trans) values increased to 2.219 +/- 0.418/min (P < 0.01) at day 4 and to 2.760 +/- 0.217/min at day 7 (P < 0.01) postirradiation. The plasma fraction (v(p)) values gradually decreased. The proportion of (n-6) polyunsaturated fatty acids (PUFA) gradually reached a peak at day 7, the proportion of (n-3) PUFA gradually decreased and the proportion of saturated fatty acids gradually increased. After irradiation, Ktrans at different times showed significant negative correlation with (n-3) PUFA (r = -0.6393, P < 0.01) and significant positive correlation with (n-6) PUFA (r = 0.6841, P < 0.05). These findings indicate that bone marrow microcirculation perfusion and vascular permeability correlated with fat content at an early time point after irradiation. A pathophysiological mechanism may exist based on fat-vascular permeability in the case of injury to bone marrow microcirculation.

• 出版日期2018-2
• 单位武汉大学; 中国科学院武汉物理与数学研究所