Remote Ischemic Preconditioning‐Mediated Neuroprotection against Stroke is Associated with Significant Alterations in Peripheral Immune Responses. (19th September 2015)

• Record Type: Journal Article
• Authors: Liu, Zong‐Jian; Chen, Chen; Li, Xiao‐Rong; Ran, Yuan‐Yuan; Xu, Tao; Zhang, Ying; Geng, Xiao‐Kun; Zhang, Yu; Du, Hui‐Shan; Leak, Rehana K.; Ji, Xun‐Ming; Hu, Xiao‐Ming
• Is Part Of: CNS neuroscience & therapeutics. Volume 22:Number 1(2016)
• Page Start: 43
• Page End: 52
• Publication Date: 2015-09-19
• Subjects: Cerebral ischemia -- Cytokine -- Immune cells -- Limb remote ischemic preconditioning; Neuropharmacology -- Periodicals; Central nervous system -- Diseases -- Effect of drugs on -- Periodicals; 612.8
• DOI: 10.1111/cns.12448
• Languages: English
• ISSNs: 1755-5930

Abstract

Summary: Aims: Remote ischemic preconditioning (RIPC) of a limb is a clinically feasible strategy to protect against ischemia–reperfusion injury after stroke. However, the mechanism underlying RIPC remains elusive. Methods: We generated a rat model of noninvasive RIPC by four repeated cycles of brief blood flow constriction (5 min) in the hindlimbs using a tourniquet. Blood was collected 1 h after preconditioning and 3 days after brain reperfusion. The impact of RIPC on immune cell and cytokine profiles prior to and after transient middle cerebral artery occlusion (MCAO) was assessed. Results: Remote ischemic preconditioning protects against focal ischemia and preserves neurological functions 3 days after stroke. Flow cytometry analysis demonstrated that RIPC ameliorates the post‐MCAO reduction of CD3 + CD8 + T cells and abolishes the reduction of CD3 + /CD161a + NKT cells in the blood. In addition, RIPC robustly elevates the percentage of B cells in peripheral blood, thereby reversing the reduction in the B‐cell population after stroke. RIPC also markedly elevates the percentage of CD43 + /CD172a + noninflammatory resident monocytes, without any impact on the percentage of CD43 − /CD172a + inflammatory monocytes. Finally, RIPC induces IL‐6 expression and enhances the elevation of TNF‐ α after stroke. Conclusion: Our results reveal dramatic immune changes during RIPC‐afforded neuroprotection against cerebral ischemia.