Radiation-induced endothelial cell loss and reduction of the relative magnitude of the blood flow in the rat spinal cord

Vascular Endothelial Growth Factor Enhanced the Angiogenesis Response of Human Umbilical Cord-Derived Mesenchymal Stromal Cells in a Rat Model of Radiation Myelopathy

“…The different sources of OPCs and different transplantation time point may account for their different conclusions between Chari and Sun's studies. The neurons in the spinal cord were primarily injured and demyelination did not occur in our irradiation spinal cord model [19,24]. We injected UC-MSCs through the tail vein at 90, 97, 104 and 111 days post-irradiation.…”

“…For clinical application, intravenous injection appears to be the easiest method of delivering therapeutics to the patient without risking further damage to the spinal cord. We applied laserDoppler flowmetry to record the relative magnitude of the spinal cord blood flow and discovered that the lowest relative magnitude of spinal cord blood flow was reached at 90 days post-irradiation [24]. Therefore, we injected UC-MSCs at 90 days post-irradiation in our rat model of radiation myelopathy, using spinal cord blood flow as a reliable indicator of the optimal time for transplantation.…”

“…SCBF was measured using a MoorLab laser-Doppler flowmeter (MoorLab Instruments, Devon, England) as described in our previous studies [19,24]. This instrument recorded the relative change in blood flow over time.…”

“…According to the method described previously by Li et al [20,21] and us [19,24], the endothelial cell density was defined as the total number of endothelial cells that contained a nucleus divided by the transverse cross-sectional area of the spinal cord, and the microvessel density was defined as the total number of microvessels that had been transversely sectioned and contained either an endothelial cell nucleus or no nucleus, divided by the transverse cross-sectional area of the spinal cord. One hotspot area in the gray matter and another hotspot area in the white matter were selected at 1009 magnification.…”

“…For the Nissl staining, two sections per rat were selected in every sixth section, and a total of ten sections per time point were carefully examined at 1009 magnification under an Olympus microscope [19,24]. According to the method described previously by Li et al [20,21] and us [19,24], the endothelial cell density was defined as the total number of endothelial cells that contained a nucleus divided by the transverse cross-sectional area of the spinal cord, and the microvessel density was defined as the total number of microvessels that had been transversely sectioned and contained either an endothelial cell nucleus or no nucleus, divided by the transverse cross-sectional area of the spinal cord.…”