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Updated: Jun 4, 2025
Oxygen-Glucose Deprivation and Reoxygenation as an In Vitro Ischemia-Reperfusion Injury Model for Studying Blood-Brain Barrier Dysfunction
Published on: May 7, 2015
Oxygen-glucose-deprived peripheral blood mononuclear cells act on hypoxic lesions after ischemia-reperfusion injury
Takeshi Kanayama1, Masahiro Hatakeyama1, Natsuki Akiyama1
1Department of Neurology, Brain Research Institute, Niigata University, 1-757 Asahimachi-dori, Chuoku, Niigata 951-8585, Japan.
Background:
Despite advances in reperfusion therapies, ischemic stroke remains a major cause of long-term disability due to residual hypoxic lesions persisting after macrovascular reperfusion. These residual hypoxic lesions, caused by microvascular dysfunction, represent an important therapeutic target. We previously demonstrated that oxygen-glucose-deprived peripheral blood mononuclear cells (OGD-PBMCs) migrate to ischemic brain regions and promote functional recovery after stroke. This recovery occurs through mechanisms involving hypoxia-inducible factor-1α, exosomal miR-155-5p, and vascular endothelial growth factor (VEGF). However, it remains unclear whether OGD-PBMCs target hypoxic regions.
Methods:
We evaluated cerebral blood flow using a laser speckle flow imaging system. Next, we utilized pimonidazole to investigate the presence of hypoxic lesions after ischemia-reperfusion injury in a rat suture occlusion model in immunohistochemical analyses. We also compared levels of a cell surface receptor in human PBMCs by flow cytometric analysis under normoxic and OGD conditions.
Results:
We found persistent pimonidazole-positive hypoxic lesions at 10- and 28-days post-reperfusion despite restored gross cerebral perfusion. Treatment with the C-X-C motif chemokine receptor 4 (CXCR4) inhibitor AMD3100 before and after OGD-PBMCs administration reduced the number of OGD-PBMCs in the brain parenchyma compared to the control group (P = 0.018). Administered OGD-PBMCs localized within these hypoxic regions via the stromal cell-derived factor-1/CXCR4 chemotactic axis. OGD-PBMCs enhanced VEGF expression, specifically within hypoxic lesions, compared to the phosphate-buffered saline group (P < 0.01). Furthermore, OGD-PBMCs reduced the number of pimonidazole-positive hypoxic cells in the ischemic core on 28 days. These findings demonstrate that OGD-PBMCs selectively migrate to and modulate the microenvironment of hypoxic lesions following cerebral ischemia-reperfusion injury.
Conclusion:
Targeting these residual hypoxic regions may underline the therapeutic effects of OGD-PBMC treatment and represent a promising strategy for improving stroke recovery despite successful recanalization.
