AIMS: Stroke causes both brain inflammation and immunodepression. Mild-to-moderate hypothermia is known to attenuate brain inflammation, but its role in stroke-induced immunodepression (SIID) of the peripheral immune system remains unknown. This study investigated the effects in rats of moderate intra-ischemic hypothermia on SIID and brain inflammation. METHODS: Stroke was induced in rats by permanent distal middle cerebral artery occlusion combined with transient bilateral common carotid artery occlusion, while body temperature was reduced to 30°C. Real-time PCR, flow cytometry, in vitro T-cell proliferation assays, in vivo delayed-type hypersensitivity (DTH) reaction and confocal microscopy were used to study SIID and brain inflammation. RESULTS: Brief intra-ischemic hypothermia helped maintain certain leukocytes in the peripheral blood and spleen and enhanced T-cell proliferation in vitro and delayed-type hypersensitivity in vivo, suggesting that hypothermia reduces SIID. In contrast, in the brain, brief intra-Ischemic hypothermia inhibited mRNA expression of anti-inflammatory cytokine IL-10 and proinflammatory mediators INF-γ, TNF-α, IL-2, IL-1β and MIP-2. Brief intra-Ischemic hypothermia also attenuated the infiltration of lymphocytes, neutrophils (MPO(+) cells) and macrophages (CD68(+) cells) into the ischemic brain, suggesting that hypothermia inhibited brain inflammation. CONCLUSIONS: Brief intra-ischemic hypothermia attenuated SIID and protected against acute brain inflammation.
AIMS: Stroke causes both brain inflammation and immunodepression. Mild-to-moderate hypothermia is known to attenuate brain inflammation, but its role in stroke-induced immunodepression (SIID) of the peripheral immune system remains unknown. This study investigated the effects in rats of moderate intra-ischemic hypothermia on SIID and brain inflammation. METHODS:Stroke was induced in rats by permanent distal middle cerebral artery occlusion combined with transient bilateral common carotid artery occlusion, while body temperature was reduced to 30°C. Real-time PCR, flow cytometry, in vitro T-cell proliferation assays, in vivo delayed-type hypersensitivity (DTH) reaction and confocal microscopy were used to study SIID and brain inflammation. RESULTS: Brief intra-ischemic hypothermia helped maintain certain leukocytes in the peripheral blood and spleen and enhanced T-cell proliferation in vitro and delayed-type hypersensitivity in vivo, suggesting that hypothermia reduces SIID. In contrast, in the brain, brief intra-Ischemic hypothermia inhibited mRNA expression of anti-inflammatory cytokine IL-10 and proinflammatory mediators INF-γ, TNF-α, IL-2, IL-1β and MIP-2. Brief intra-Ischemic hypothermia also attenuated the infiltration of lymphocytes, neutrophils (MPO(+) cells) and macrophages (CD68(+) cells) into the ischemic brain, suggesting that hypothermia inhibited brain inflammation. CONCLUSIONS: Brief intra-ischemic hypothermia attenuated SIID and protected against acute brain inflammation.
Authors: Stephen A Bernard; Timothy W Gray; Michael D Buist; Bruce M Jones; William Silvester; Geoff Gutteridge; Karen Smith Journal: N Engl J Med Date: 2002-02-21 Impact factor: 91.245
Authors: Seetha Shankaran; Abbot R Laptook; Richard A Ehrenkranz; Jon E Tyson; Scott A McDonald; Edward F Donovan; Avroy A Fanaroff; W Kenneth Poole; Linda L Wright; Rosemary D Higgins; Neil N Finer; Waldemar A Carlo; Shahnaz Duara; William Oh; C Michael Cotten; David K Stevenson; Barbara J Stoll; James A Lemons; Ronnie Guillet; Alan H Jobe Journal: N Engl J Med Date: 2005-10-13 Impact factor: 91.245
Authors: Kristina A Kigerl; Juan Pablo de Rivero Vaccari; W Dalton Dietrich; Phillip G Popovich; Robert W Keane Journal: Exp Neurol Date: 2014-08 Impact factor: 5.330