Toll-like receptor-4 and cytokine cascade in stroke after exercise. Neurol Res 2010 Mar;32(2):123-6
Date
09/04/2009Pubmed ID
19726014DOI
10.1179/016164109X12464612122812Scopus ID
2-s2.0-77949475533 (requires institutional sign-in at Scopus site) 35 CitationsAbstract
OBJECTIVES: As part of the innate immune system, activation of Toll-like receptor-4 by inflammatory mediators causes the release of inflammatory cytokines, leading to cellular damage. Exercise for 3 weeks has been shown to provide neuroprotection against ischemia/reperfusion insults by decreasing inflammation. This study explores the expression of Toll-like receptor-4 in brain parenchyma during an ischemic stroke after exercise, in association with brain injury.
METHODS: Adult male Sprague-Dawley rats were studied in four groups (control, exercise, stroke and stroke after exercise). Exercise consisted of 30 minutes of treadmill running daily for 3 weeks. Using an intraluminal filament, a stroke was induced by 2 hour middle cerebral artery occlusion. Nissl staining was used to determine brain infarct volume. Brain Toll-like receptor-4 messenger RNA expression and protein levels were determined by real time reverse transcriptase polymerase chain reaction and Western blot, respectively.
RESULTS: Exercise significantly (p<0.05) decreased Toll-like receptor-4 messenger RNA and protein expression, in association with significantly (p<0.05) reduced brain infarct volume. The stroke group had significantly (p<0.05) increased levels of Toll-like receptor-4 expression compared to the control, whereas the exercise/stroke group was significantly (p<0.05) attenuated.
CONCLUSION: Exercise reduced Toll-like receptor-4 expression within brain tissue in response to ischemia/reperfusion insult. This is the first paper, to our knowledge, indicating the correlation between exercise, Toll-like receptor-4 expression and reduced brain infarct volume.
Author List
Zwagerman N, Plumlee C, Guthikonda M, Ding YAuthor
Nathan Zwagerman MD Associate Professor in the Neurosurgery department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsBrain Infarction
Cytokines
Exercise Test
Infarction, Middle Cerebral Artery
Ischemic Preconditioning
Male
Physical Conditioning, Animal
Random Allocation
Rats
Rats, Sprague-Dawley
Stroke
Toll-Like Receptor 4
