Iranian brown propolis possesses neuroprotective effect against ischemic neuronal damage in mice

Introduction: Stroke is one of the leading causes of death and disability worldwide. Propolis, a polyphenol-rich resinous product processed by honeybees from a variety of plant sources, has a set of biological activities. We investigated the neuroprotective effect of Iranian brown propolis (IBP) in a mouse model of permanent middle cerebral artery occlusion (MCAO). Methods: Experimentally, water extracts of propolis (WEPs) were obtained from Kerman (KeWEP) and Khorasan Razavi (KhWEP) provinces, Iran. The chemical characterization and total polyphenol content of WEPs were determined using the Folin–Ciocalteu assay and gas chromatography-mass spectrometry (GC-MS). Animals were divided into eight experimental groups including: sham, control, and three groups each of which KeWEP- and KhWEP-treated mice. The drugs were administered at doses of ۳۰, ۱۰۰ and ۲۰۰ mg/kg, intraperitoneally (IP), during four different time points. Infarct volume and brain edema were measured at ۴۸ h. Behavioral tests were evaluated at ۴, ۲۴ and ۴۸-hour post stroke. Results: The total polyphenol content was ۱۱۰۰ and ۱۴۰۰ mg/L in KhWEP and KeWEP respectively. Compared to the control group, the doses of ۱۰۰ and ۲۰۰ mg/kg in both samples decreased infarct volume. Brain edema was also reduced in all treatment groups. The dose of ۲۰۰ mg/kg in both samples and ۱۰۰ mg/kg in the KeWEP-treated group significantly increased grasping ability. Sensory-motor function was improved in all groups, too. Conclusion: These results suggest that IBP may reduce ischemic brain injury by its neuroprotective effect on focal cerebral ischemia.