The Toxic Effect Of Eprinomycin On Mouse Neuroblastoma Cell (N2a)

Eprinomycin was a member of avermectin family which belonged to Macrolide antibiotics. Avennectin are used didespread as antiparasitic agents and insecticides. EPR was an antiparasitic drug which was allowed using in dairy cow. The previous studies on the mechanism of action of the avermectins demonstrated the ability of AVMs to openγ-aminobutyric acid(GABA)-gate chloride channels and glutamate-gated chloride channels and they are important inhibitory neurotransmitter in the nematode somatic neuromuscular system. However, more research is needed to determine the relative importance of possibly other receptors, in different parasitic nematodes and different life cycle stages of parasitic nematodesand MLs cause a variety of effects in nematodesm from inhibition of pharyngeal pumping, paralysis and activation of body muscle these contrary paralytic/activation effects are concentration and time-dependent and inhibition of reproduction. It suggests that there is still much to discover about the true mechanisms of AVMs。In this study, we investigated the influences of EPR on intra-cellular concentration of Cl-, active of ATP-ase, survival, proliferation, cell cycle and apoptosis of mouse nueroblastoma cell line N2a cells. And we used the RNAi-N2a cells which knockdown the expression of P-glycoprotein (Pgp) to study the role of Pgp in regulation of cell proliferation, cell cycle and apoptosis.The results of the effects of EPR on intra-cellular Cl- concentration and activity of ATPase were shown that after treatment of EPR for 1h the intra-cellular Cl- -concentration was increased, but after treatment of EPR for 24h the result were not show differentiation compared with control. This result suggested that EPR could increas intra-cellular Cl--concentration only in the initial stage. In addition, EPR can reduce activity of total-ATPase obviously and the reducing the activity of Ca+-Mg+-ATPase was its major effect.The effect of EPR on cell proliferation, cell cycle and apoptosis that contribute to this effect were investigated. Treatment of N2a cells with EPR suppressed cell proliferation and reduced cell viability in a dose-dependent manner. The EPR affected cell cycle progression by arresting the cell cycle at G1 phase in N2a cells and arrested the cell cycle in a dose-dependent and time-dependent; In addition, EPR could induce nuclear chromatin aggregation exceptionally, but the cell apoptotic body was not observed and the same result were observed in test using AnnixinV-FITC/PI kit. Our results indicated that there is no significant difference in cell proliferation among normal N2a cells and N2a/shRNA-Pgp cells. And knockdown of Pgp expression can slow down the cell cycle process, but the low expression of Pgp may enhance the toxicity of AVMs on N2a cell line.