The Flavonoid Apigenin Protects Brain Neurovascular Coupling against Amyloid-β25-35-Induced Toxicity in Mice

Apigenin, one of the most common flavonoids, has demonstrated anti-inflammatory, anticarcinogenic, and free radical-scavenging activities. Recent studies revealed its protective effects against amyloid-beta (A beta)-induced neurotoxicity, but the mechanism was unclear. In the present study, we aimed to explore the anti-amnesic and protective effects of apigenin against A beta(25-35)-induced toxicity and the underlying mechanisms in the cerebral cortex in mice. The learning and memory impairments, changes in morphology of major components of neurovascular unit, ultrastructural changes and oxidative stress of cerebral cortex, cerebrovascular dysfunction, and neuronal changes were detected after oral administration of apigenin continuously for 8 days. Our results demonstrate that oral administration of apigenin for A beta(25-35)-induced amnesic mice conferred robust neurovascular coupling protection, involving improvement of the learning and memory capabilities, maintenance of neurovascular unit integrity, modulation of microvascular function, reduction of neurovascular oxidative damage, increase of regional cerebral blood flow, improvement of cholinergic system involving the inhibition of AChE activity and elevation of ACh level, and modification of BNDF, TrkB, and phospho-CREB levels.