Docosahexaenoic acid (DHA) and lutein are important nutrients for brain health. Whether there were synergistic effects of DHA and lutein on the protection against neuronal cell damage induced by oxidative stress remained unclear. The present study was designed to investigate the synergistic effects of DHA and lutein against hydrogen peroxide (H2O2)-induced oxidative challenge in PC12 cells. PC12 cells were divided into different groups and received H2O2 (80 μM), lutein (20 μM)+H2O2 (80 μM), DHA (25 μM)+H2O2 (80 μM), and lutein (20 μM)+DHA (25 μM)+H2O2 (80 μM), respectively. The results indicated that pre-treatment of cells with lutein, DHA and DHA+lutein could significantly antagonize the H2O2-mediated growth inhibition and morphological changes in PC12 cells (p<0.05). Molecularlevel studies indicated that the DHA+lutein combination can significantly inhibit the mRNA expression of AMAD10 and BAX. Furthermore, Western blot analysis demonstrated that DHA+lutein synergistically inhibits the phosphorylation of JNK1/2. The results of the present study suggest that DHA and lutein in combination may be utilized as potent antioxidative compounds, with potential preventative or palliative effects on age-related neurodegenerative diseases.
Keywords: DHA; MAPK signal pathway; PC12 cell; lutein; oxidative stress.