OBJECTIVESOxidative stress is considered the potential risk to the development of dementia. Some medicines, vitamins, and diet supplements have been suggested to have possible benefits via the antioxidative effects to slow the decline of cognitive function in demented and non-demented individuals. However, few studies were conducted to examine their functions, especially in composite diet supplements. Hu-Yi-Neng is a composite diet supplement, including ginkgo biloba, extract of pine bark, phosphatidyl serine, docosahexaenoic acid, and folic acid, used extensively in Taiwan. Therefore, our aim is to investigate the potential protective effects of Hu-Yi-Neng on human neuron cells. MATERALS AND METHODS: H2O2-induced neuronal toxicity was characterized in SH-SY5Y human neuroblastoma cells by the decrease of cell viability using PrestoBlue™ assay and by the increase of intracellular reactive oxygen species (ROS) level using DCFH-DA (2', 7'-dichlorodihydrofluorescin diacetate) assays. HO-1 mRNA expression was detected by real-time PCR. Akt and Erk 1/2 proteins were detected by western blotting.RESULTSPretreatment with Hu-Yi-Neng significantly reversed the decrease in cell viability induced by H2O2 in SH-SY5Y cells. Furthermore, Hu-Yi-Neng dose-dependently suppressed the elevation of intracellular reactive oxygen species (ROS) level. Hu-Yi-Neng protected SH-SY5Y cells from oxidative stress may via the increase in mRNA expression of heme oxygenase-1 (HO-1), an antioxidant enzyme. In addition, Hu-Yi-Neng inhibited H2O2-induced phosphorylation of Akt kinase but further increased the phosphorylation of Erk 1/2.CONCLUSIONOur results suggest that Hu-Yi-Neng has protective effect against oxidative stress-induced neuron cell loss and it could be an ideal composite diet supplement for preventing neurodegenerative diseases.