PLC-CN-NFAT1 signaling-mediated Aβ and IL-1β crosstalk synergistically promotes hippocampal neuronal damage

Alzheimer ' s disease (AD) is a progressive neurodegenerative disease. Neuronal calcium overload plays an important role in A beta deposition and neuroinflammation, which are strongly associated with AD. However, the specific mechanisms by which calcium overload contributes to neuroinflammation and AD and the relationship between them have not been elucidated. Phospholipase C (PLC) is involved in regulation of calcium homeostasis, and CN-NFAT1 signaling is dependent on intracellular Ca 2 + ([Ca 2 + ] i ) to regulate transcription of genes. Therefore, we hypothesized that the PLC-CN-NFAT1 signaling might mediate the interaction between A beta and inflammation to promote neuronal injury in AD. In this experiment, the results showed that the levels of A beta , IL-1 beta and [Ca 2 + ] i in the hippocampal primary neurons of APP/PS1 mice (APP neurons) were significantly increased. IL-1 beta exposure also significantly increased A beta and [Ca 2 + ] i in HT22 cells, suggesting a close association between A beta and IL-1 beta in the development of AD. Furthermore, PLC activation induced significant calcium homeostasis imbalance, cell apoptosis, A beta and ROS production, and significantly increased expressions of CN and NFAT1, while PLC inhibitor significantly reversed these changes in APP neurons and IL-1 beta -induced HT22 cells. Further results indicated that PLC activation significantly increased the expressions of NOX2, APP, BACE1, and NCSTN, which were inhibited by PLC inhibitor in APP neurons and IL-1 beta -induced HT22 cells. All indications point to a synergistic interaction between A beta and IL-1 beta by activating the PLC-CN-NFAT1 signal, ultimately causing a vicious cycle, resulting in neuronal damage in AD. The study may provide a new idea and target for treatment of AD.