Hydroxychavicol inhibits immune responses to mitigate cognitive dysfunction in rats

This study was carried out to investigate the protective effect of Hydroxychavicol (HC), a phenolic compound derived from Piper betel on experimentally induced Alzheimer's disease (AD) in rat. HC at graded doses administered orally once daily for a duration of 21 days significantly improved the cognitive impairment and attenuated the elevated levels of pro-inflammatory cytokines like IL-1 beta, TNF alpha, IL-6, nitric oxide, lipid peroxidation and both β- and γ-secretase enzymatic activities. Chronic oral administration of HC also significantly reversed the decline in acetyl cholinesterase and glutathione (GSH) activity induced by streptozotocin (STZ) injection. The results also suggest the inhibition of elevated levels of CD3+ T cells and CD19+ B cells as well as CD3+ T cell specific IFN-γ in blood of the experimental animals. There was however no change in blood glucose levels in the animals treated with HC. The result of the present study demonstrates the effectiveness of HC in preventing the cognitive deficit.