The effects of pistachio hydroalcoholic extract on stroke in permanent middle cerebral artery occlusion in ovariectomized female rats

Background: Phytoestrogens, found in abundance in the extracts of oilseeds such as pistachios, have estrogen-like and anti-inflammatory effects. This study investigated the effects of pistachio kernel extract on stroke in ovariectomized rats. Materials and Methods: This study was conducted on four groups of female rats weighing 200-250 g. The groups included the control group and three groups treated with pistachio hydroalcoholic extracts (100, 250, and 500 mg/kg) (n = 10 per group). One week after ovariectomy and its confirmation (via vaginal smear examination), the extracts were gavaged for four weeks and at the end of the fourth week, stroke was induced by closing the middle cerebral artery. Infarct volume and cerebral edema were measured 72 hours after brain extraction and staining with tetrazolium chloride. Neurological disorders were measured using the Bederson ranking system and sensory-motor disorders were measured via two behavioral tests including the sticky test and hanging test (hanging the animal from a thin wire string). Furthermore, cerebral edema was measured by determining the percentage of water in the affected hemisphere compared to the intact hemisphere. Results: Pistachio extract (especially at a dose of 500 mg/kg) reduced the risk of infarct volume (p <0.0001) and cerebral edema (p <0.0001) in the treatment groups compared to the animals in the control group. Pistachio extract also improved neurological disorders and sensorimotor function. Conclusion: According to its anti-inflammatory, antimicrobial, antioxidant, and estrogen-like properties, pistachio extract improves the stroke complications in ovariectomized female rats.