Neuroprotective effects of cordycepin inhibit Aβ-induced apoptosis in hippocampal neurons.

In Alzheimer's disease (AD), β-amyloid (Aβ) protein toxicity increases the formation of reactive oxygen species (ROS) and intracellular calcium levels, resulting in neuronal dysfunction, neurodegenerative disorders, and cell death. Cordycepin is a derivative of the nucleoside adenosine; also, it is speculated to exert neuroprotective effects against Aβ-induced oxidative toxicity in hippocampal neurons. In the present study, the fluorescence detection method and whole-cell patch-clamp recordings were used to study the neuroprotective effects against Aβ-induced toxicity in the primary hippocampal cultured neurons. The results revealed that Aβ25-35 toxicity causes increased cellular ROS production and abnormal calcium homeostasis in hippocampal neurons. Moreover, Aβ25-35-induced cytotoxicity led to a series of downstream events, including the activation of acetylcholinesterase, increased p-Tau expression, and increased apoptosis. Cordycepin inhibits ROS production, elevated levels of Ca2+ induced by Aβ25-35, and the activation of acetylcholinesterase; all these are involved in oxidative-induced apoptosis. In addition, it decreases the increased p-Tau expression that plays a key role in the initiation of the AD. Results showed that the anti-apoptotic effects of cordycepin are partially dependent on the activation of adenosine A1 receptor, whereas an antagonist selectively attenuated the neuroprotective effects of cordycepin. Collectively, these results suggest that cordycepin could be a potential future therapeutic agent for neuronal disorders, such as AD.