Olive leaf extract inhibits lead poisoning-induced brain injury**

Yu Wang; Shengqing Wang; Wenhui Cui; Jiujun He; Zhenfu Wang; Xiaolu Yang

doi:10.3969/j.issn.1673-5374.2013.22.001

摘要： Olive leaves have an antioxidant capacity, and olive leaf extract can protect the blood, spleen and hippocampus in lead-poisoned mice. However, little is known about the effects of olive leaf extract on lead-induced brain injury. This study was designed to determine whether olive leaf extract can inhibit lead-induced brain injury, and whether this effect is associated with antioxidant capacity. First, we established a mouse model of lead poisoning by continuous intragastric administration of lead acetate for 30 days. Two hours after successful model establishment, lead-poisoned mice were given olive leaf extract at doses of 250, 500 or 1 000 mg/kg daily by intragastric administration for 50 days. Under the transmission electron microscope, olive leaf extract attenuated neuronal and capil ary injury and reduced damage to organel es and the matrix around the capil aries in the frontal lobe of the cerebral cortex in the lead-poisoned mice. Olive leaf extract at a dose of 1 000 mg/kg had the greatest protective effect. Spectrophotometry showed that olive leaf extract significantly in-creased the activities of superoxide dismutase, catalase, alkaline phosphatase and acid phospha-tase, while it reduced malondialdehyde content, in a dose-dependent manner. Furthermore, im-munohistochemical staining revealed that olive leaf extract dose-dependently decreased Bax pro-tein expression in the cerebral cortex of lead-poisoned mice. Our findings indicate that olive leaf extract can inhibit lead-induced brain injury by increasing antioxidant capacity and reducing apop-tosis.