Tieguanyin Oolong tea extracts alleviate behavioral abnormalities by modulating neuroinflammation in APP/PS1 mouse model of Alzheimer's disease. - GreenMedInfo Summary

Alzheimer's disease (AD) is a common neurodegenerative disease; tea components have important neuroprotective effects. This article explores the effects and mechanisms of Qingxiang(Tgy-Q), Nongxiang(Tgy-N), and Chenxiang(Tgy-C) extracts on APP/PS1 AD model mice. Morris water maze and new object recognition experiments show thatextracts can effectively enhance the cognitive ability of APP/PS1 mice. H&E staining, Nissl staining, and immunohistochemical staining show thatextracts make nerve cell boundaries and nucleoli become clearer, relieve nucleus pyknosis, and effectively reduce Aβ1-40 and Aβ1-42 in the hippocampus and cortex. They also restore the morphology of microglia and astrocytes. In addition,extracts can balance the oxidative stress level in the brain of APP/PS1 mice by improving the antioxidant capacity. Western blot results show thatextracts can reduce the expression of NF-κB p65, TNF-α, IL-1β, IL-6, COX-2, and iNOS in mouse brain, which demonstrates thatextracts improves cognitive ability by alleviating inflammation. This article demonstrates for the first time thatextracts can inhibit the excessive activation of the NF-κB p65 signaling pathway and improve the antioxidant capacity in the cerebral cortex and hippocampus, to improve the cognitive ability of APP/PS1 mice. Our results shed light into the beneficial oftea extracts on preventing and alleviating AD diseases.