The neuroprotective effects of the combined extract of mulberry fruit and mulberry leaf against hydrogen peroxide-induced cytotoxicity in SH-SY5Y Cells

The prevalence of dementia is increasing, and most of the causes are related to neuronal cell death. Unfortunately, no effective strategy is available for protecting against this condition. Based on the use of the synergistic concept together with the positive modulation effect of both mulberry fruit and mulberry leaf on dementia, we hypothesized that the combined extract of mulberry fruit and mulberry leaf (MFML) should mitigate neuronal cell death. Neuronal cell damage was induced in SH-SY5Y cells by exposure to hydrogen peroxide at a dose of 200 μM. SH-SY5Y cells were given MFML at doses of 62.5 and 125 μg/mL before induced cytotoxicity. Then, the cell viability was determined via MTT assay, and the possible underlying mechanisms were investigated via the alterations of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), nuclear factor-κB (NF-κB), and tumor necrosis factor-alpha (TNF-α), together with apoptotic factors including (B-cell lymphoma 2) BCL2, Casapase-3 and Caspase-9. The results showed that MFML significantly enhanced cell viability. It also significantly decreased MDA level, NF-κB, TNF-α, Casapase-3, Caspase-9, but increased SOD, GSH-Px and BCL2. These data demonstrated the neuroprotective effect of MFML. The possible underlying mechanisms might occur partly via the improvement of the inappropriate apoptotic mechanisms via BCL2, Casapase-3 and Caspase-9 together with the decrease in neurodegeneration induced by the reduction of inflammation and oxidative stress. In conclusion, MFML is a potential neuroprotectant candidate against neuronal cell injury. However, toxicity, animal studies, and clinical trials are essential to confirm these benefits.