title: The neuroprotective effect of post ischemic brief mild hypothermic treatment correlates with apoptosis, but not with gliosis in endothelin-1 treated rats.
abstract: BACKGROUND
  Stroke remains one of the most common diseases with a serious impact on quality of life but few effective treatments exist. Mild hypothermia (33°C) is a promising neuroprotective therapy in stroke management. This study investigated whether a delayed short mild hypothermic treatment is still beneficial as neuroprotective strategy in the endothelin-1 (Et-1) rat model for a transient focal cerebral ischemia. Two hours of mild hypothermia (33°C) was induced 20, 60 or 120 minutes after Et-1 infusion. During the experiment the cerebral blood flow (CBF) was measured via Laser Doppler Flowmetry in the striatum, which represents the core of the infarct. Functional outcome and infarct volume were assessed 24 hours after the insult. In this sub-acute phase following stroke induction, the effects of the hypothermic treatment on apoptosis, phagocytosis and astrogliosis were assessed as well. Apoptosis was determined using caspase-3 immunohistochemistry, phagocytic cells were visualized by CD-68 expression and astrogliosis was studied by glial fibrillary acidic protein (GFAP) staining.
  
  
  RESULTS
  Cooling could be postponed up to 1 hour after the onset of the insult without losing its positive effects on neurological deficit and infarct volume. These results correlated with the caspase-3 staining. In contrast, the increased CD-68 expression post-stroke was reduced in the core of the insult with all treatment protocols. Hypothermia also reduced the increased levels of GFAP staining, even when it was delayed up to 2 hours after the insult. The study confirmed that the induction of the hypothermia treatment in the Et-1 model does not affect the CBF.
  
  
  CONCLUSIONS
  These data indicate that in the Et-1 rat model, a short mild hypothermic treatment delayed for 1 hour is still neuroprotective and correlates with apoptosis. At the same time, hypothermia also establishes a lasting inhibitory effect on the activation of astrogliosis.
authors.affiliation: Department of Pharmaceutical Chemistry and Drug Analysis, Center for Neuroscience, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium.
authors.forename: Tine
authors.initials: T
authors.lastname: Zgavc
authors.forename: An-Gaëlle
authors.initials: AG
authors.lastname: Ceulemans
authors.forename: Said
authors.initials: S
authors.lastname: Hachimi-Idrissi
authors.forename: Ron
authors.initials: R
authors.lastname: Kooijman
authors.forename: Sophie
authors.initials: S
authors.lastname: Sarre
authors.forename: Yvette
authors.initials: Y
authors.lastname: Michotte
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D020520:Brain Infarction / Q000209:etiology; D002545:Brain Ischemia / Q000139:chemically induced / Q000150:complications / Q000628:therapy; D053148:Caspase 3 / Q000378:metabolism; D002452:Cell Count; D002560:Cerebrovascular Circulation / Q000187:drug effects; D004195:Disease Models, Animal; D019332:Endothelin-1 / Q000009:adverse effects*; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D005911:Gliosis / Q000209:etiology* / Q000628:therapy; D007036:Hypothermia, Induced / Q000379:methods*; D017078:Laser-Doppler Flowmetry; D008297:Male; D009069:Movement Disorders / Q000209:etiology; D009460:Neurologic Examination; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013223:Statistics as Topic; D013997:Time Factors; D000097382:CD68 Molecule
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D053148:Caspase 3; D019332:Endothelin-1; D005904:Glial Fibrillary Acidic Protein; C067980:CD68 antigen, human; D000097382:CD68 Molecule