SK3 钾通道通过 PI3K/Akt-ERK 通路介导 Cu2+-Aβ 复合物所致 小胶质细胞激活.

Objective: To investigate the role of Ca2+-activated small conductance SK3 potassium channels in Cu-Aβ complex-induced microglial activation and the downstream signaling pathway. Methods: The Cu-Aβ complex-induced release of tumor necrosis factor-α (TNF-α) and hydrogen peroxide (H2O2) in cell culture supernatants were detected using ELISA and the Amplex Red reagent. The levels of mRNA and protein of potassium channels as well as phosphorylation levels of related signaling molecules were detected by qPCR and Western blot. Results: (1) The experimental results of pretreatment with different ion channel blockers or potassium channel blockers of different subtypes showed that SK3 channels may mediate microglial activation caused by Cu-Aβ complex. (2) The results of qPCR and Western blot detection showed that Cu-Aβ complex could upregulate SK3 mRNA and protein expression in microglia. (3) The application of SK3-siRNA to knock down SK3 expression showed that the downregulation of SK3 expression significantly inhibited microglial activation caused by Cu-Aβ complex. (4) The experimental results of Western blot detection showed that PI3K/Akt signaling and ERK signaling were involved in microglial activation caused by Cu-Aβ complex. (5) The results of experiments using specific blockers of signaling molecules further showed that SK3 channels may lie upstream of the PI3K/Akt-ERK signaling pathway during the microglial activation induced by the Cu-Aβ complex. Conclusions: SK3 channels mediate microglial inflammatory responses induced by Cu-Aβ complex through the downstream PI3K/Akt-ERK signaling pathway [ABSTRACT FROM AUTHOR]