TY - JOUR
T1 - Exercise pre-conditioning reduces brain inflammation in stroke via tumor necrosis factor-α, extracellular signal-regulated kinase 1/2 and matrix metalloproteinase-9 activity
AU - Curry, Alecia
AU - Guo, Miao
AU - Patel, Rohit
AU - Liebelt, Brandon
AU - Sprague, Shane
AU - Lai, Qin
AU - Zwagerman, Nathan
AU - Cao, Frank X.
AU - Jimenez, David
AU - Ding, Yuchuan
PY - 2010/9/1
Y1 - 2010/9/1
N2 - Objective: We sought to determine whether cerebral inflammation in ischemic rats was reduced by a neuroprotective action of pre-ischemic tumor necrosis factor-α up-regulation, which down-regulated matrix metalloproteinase-9 activity via extracellular signal-regulated kinase 1/2 phosphorylation. Material and methods: Adult male Sprague-Dawley rats were subjected to 30 minutes of exercise on a treadmill for 3 weeks. Stroke was induced by a 2 hour middle cerebral artery occlusion using an intraluminal filament. The exercised animals were treated with tumor necrosis factor-α antibody, UO126 (extracellular signal-regulated kinase 1/2 inhibitor), or both UO126 and doxycycline (matrix metalloproteinase-9 inhibitor). Brain infarct volume was assessed using Nissl staining. Leukocyte infiltration was evaluated using myeloperoxidase immunostaining. Intercellular adhesion molecule-1 and matrix metalloproteinase protein levels were determined by Western blot, and enzyme activity was evaluated using zymography. Results: There was a significant decrease in neurological deficits, brain infarct volume and leukocyte infiltration, in association with reduction in matrix metalloproteinase-9 and intercellular adhesion molecule-1 expression in exercised animals. Exercised animals treated with either tumor necrosis factor-α antibody or with UO126 showed a reversal of neurological outcome, infarct volume and leukocyte infiltration. Matrix metalloproteinase-9 activity was reversed, at least partially, but the intercellular adhesion molecule-1expression was not. Neuroprotection remained when the exercised ischemic rats were treated with both UO126 and doxycycline. Conclusion: These results suggest that exercise-induced up-regulation of tumor necrosis factor-α before stroke and extracellular signal-regulated kinase 1/2 phosphorylation play a role in decreasing brain inflammation by regulating matrix metalloproteinase-9 activity.
AB - Objective: We sought to determine whether cerebral inflammation in ischemic rats was reduced by a neuroprotective action of pre-ischemic tumor necrosis factor-α up-regulation, which down-regulated matrix metalloproteinase-9 activity via extracellular signal-regulated kinase 1/2 phosphorylation. Material and methods: Adult male Sprague-Dawley rats were subjected to 30 minutes of exercise on a treadmill for 3 weeks. Stroke was induced by a 2 hour middle cerebral artery occlusion using an intraluminal filament. The exercised animals were treated with tumor necrosis factor-α antibody, UO126 (extracellular signal-regulated kinase 1/2 inhibitor), or both UO126 and doxycycline (matrix metalloproteinase-9 inhibitor). Brain infarct volume was assessed using Nissl staining. Leukocyte infiltration was evaluated using myeloperoxidase immunostaining. Intercellular adhesion molecule-1 and matrix metalloproteinase protein levels were determined by Western blot, and enzyme activity was evaluated using zymography. Results: There was a significant decrease in neurological deficits, brain infarct volume and leukocyte infiltration, in association with reduction in matrix metalloproteinase-9 and intercellular adhesion molecule-1 expression in exercised animals. Exercised animals treated with either tumor necrosis factor-α antibody or with UO126 showed a reversal of neurological outcome, infarct volume and leukocyte infiltration. Matrix metalloproteinase-9 activity was reversed, at least partially, but the intercellular adhesion molecule-1expression was not. Neuroprotection remained when the exercised ischemic rats were treated with both UO126 and doxycycline. Conclusion: These results suggest that exercise-induced up-regulation of tumor necrosis factor-α before stroke and extracellular signal-regulated kinase 1/2 phosphorylation play a role in decreasing brain inflammation by regulating matrix metalloproteinase-9 activity.
KW - Ischemia reperfusion injury
KW - intercellular adhesion molecule
KW - leukocyte infiltration
KW - matrix metalloproteinase-9
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U2 - 10.1179/174313209X459101
DO - 10.1179/174313209X459101
M3 - Article
C2 - 19682410
AN - SCOPUS:77955644654
VL - 32
SP - 756
EP - 762
JO - Neurological Research
JF - Neurological Research
SN - 0161-6412
IS - 7
ER -