Robust docosahexaenoic acid-mediated neuroprotection in a rat model of transient, focal cerebral ischemia.
OBJECTIVE
Docosahexaenoic acid (DHA; 22:6n-3), an omega-3 essential fatty acid family member, is the precursor of neuroprotectin D1, which downregulates apoptosis and, in turn, promotes cell survival. This study was conducted to assess whether DHA would show neuroprotective efficacy when systemically administered in different doses after middle cerebral artery occlusion (MCAo) in rats.


METHODS
Sprague-Dawley rats were anesthetized with isoflurane and subjected to 2 hour of MCAo. Animals were treated with either DHA (low doses=3.5 or 7 mg/kg; medium doses=16 or 35 mg/kg; and high dose=70 mg/kg) or an equivalent volume of saline intravenously 3 hours after MCAo onset. Neurologic status was evaluated during occlusion (60 minutes) and on days 1, 2, 3, and 7 after MCAo. Seven days after MCAo, brains were perfusion-fixed, and infarct areas and volumes were determined.


RESULTS
Only the low and medium doses of DHA significantly improved the neurologic score compared with vehicle-treated rats at 24 hours, 48 hours, 72 hours, and 7 days. DHA markedly reduced total corrected infarct volume in all treated groups compared with vehicle-treated rats (3.5 mg/kg, 26+/-9 mm(3); 7 mg/kg, 46+/-12 mm(3); 16 mg/kg, 37+/-5 mm(3); and 35 mg/kg, 34+/-15 mm(3) vs vehicle, 94+/-12 mm(3)). Cortical and striatal infarct volumes were also significantly reduced by treatment with DHA. No neuroprotective effects were observed with 70 mg/kg DHA.


CONCLUSIONS
We conclude that DHA experimental therapy at low and medium doses improves neurologic and histologic outcomes after focal cerebral ischemia and might provide benefits in patients after ischemic stroke.
Belayev
Ludmila
L
Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA. lbelay@lsuhsc.edu
Khoutorova
Larissa
L
Atkins
Kristal D
KD
Bazan
Nicolas G
NG
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002545:Brain Ischemia / Q000188:drug therapy* / Q000473:pathology; D002470:Cell Survival / Q000187:drug effects; D004195:Disease Models, Animal; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects; D008297:Male; D018696:Neuroprotective Agents / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
D018696:Neuroprotective Agents; D004281:Docosahexaenoic Acids