Vitamin E Derivative Alpha-Tocotrienol Failed to Show Neuroprotective Effects after Embolic Stroke in Rats

Document Type : Original Article


1 Department of Physiology, School of Medicine, Rafsanjan University of Medical Sciences, Rafsanjan, Iran

2 Department of Physiology, School of Medicine, West Azarbaeejan University of Medical Sciences, Oroomiah, Iran


Previous studies have demonstrated that pretreatment with alpha-tocotrienol (a-TCT) can reduce ischemic damage in mice following middle cerebral artery (MCA) occlusion. It is also reported to decrease stroke- dependent brain tissue damage in 12-Lox-deficient mice and spontaneously hypertensive rats. In the present study, the neuroprotective effects of a-TCT and rosiglitazone (RGZ) at 3 hr after cerebral ischemia were investigated.
Materials and Methods
Stroke was induced by embolizing a preformed clot into the MCA. Rats were assigned to vehicle, a-TCT (1 or 10 mg/kg), RGZ and sham-operation.
Compared to the control group, only RGZ decreased infarct volume (P<0.05), neurological deficits (P<0.05) and sensory impairments (P<0.01) but low and high doses of a-TCT did not show any significant neuroprotective effect.
Our data showed that a-TCT was not neuroprotective at 3 hr after the embolic model of stroke. Further studies should be undertaken to clarify the neuroprotective effects of a-TCT after stroke.


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