The protective effect and underlying mechanism of Hainan papaya water extract against neuronal apoptosis induced by A β 40

Objective:To investigate whether Hainan papayas has protective effects in an Aimary neuron injury model and elucidate the underlying molecular mecha β 40-induced prnism.Methods:Cultured primary neurons from the dorsal root ganglia(DRG) of Sprague-Dawley(SD) rats were treated with 20 μM A culture medium β 40 peptide,100 μg/L Hainan papaya water extract,peptide plus extract,or for 24 h.Cell viability was measured by MTT assay,and neuronal apoptosis was evaluated by DAPI staining.ERK signaling pathway-associated molecule activation and changes in Bax expression were analyzed by Western blotting and immunofluorescence.Results:A cell viability rate of(44.11±6.59)% in the Ading different concentrations of the extract β 40 group was rescued to(79.13±6.64)% by ad.DAPI showed pyknotic nuclei in 39.5% of A β 40-treated cells;the fraction dropped to 17.4% in the 100 μg/L extract group.ERK phosphorylation was observed in the Aent with 100 μg/L extract.Hainan papaya water ex β 40 group but was ameliorated by pretreatmtract also prevented Ation of MEK,RSK1 and CREB associated with ERK signaling and d β 40-induced phosphorylaownregulated Bax expression in the neurons.Conclusion:The resultss suggest that Hainan papaya water extract has protective effects on neurons;the mechanism may be related to suppression of ERK signaling activation.