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Oxidative stress is a key factor of and closely implicated in the pathogenesis of Alzheimer's disease (AD). We herein used tert-butyl hydroperoxide (t-BHP) to induce oxidative stress and mimic oxidative neurotoxicity in vitro. Lycopene is a natural antioxidant that has a strong ability to eliminate free radicals and shows effective protection in some neurodegenerative disease models. However, the effect of lycopene on t-BHP-induced neuronal damage in primary mouse neurons is unknown. This study aimed to investigate the effects of lycopene on t-BHP-induced neuronal damage and the related mechanisms. We found that lycopene pretreatment effectively enhanced the cell viability, improved the neuron morphology, increased the GSH/GSSG level, restored the mitochondrial membrane potential (ΔΨm) and decreased reactive oxygen species generation. Furthermore, lycopene reduced the ratios of Bax:Bcl-2 and cleaved caspase-3:caspase-3 and the level of cytochrome C, increased the levels of synaptophysin (SYP) and postsynaptic density 95 (PSD95) and activated the PI3K/Akt pathway. In conclusion, lycopene attenuated oxidative stress and reduced t-BHP-induced cell apoptosis, and the mechanism is likely related to activation of the PI3K/Akt pathway. Therefore, lycopene is a potential agent for preventing oxidative stress-mediated AD.

Background/purpose: Ultraviolet-A (UVA) radiation can induce photoaging and skin cancer, but means to prevent or treat UVA-induced skin damage require further study. We investigated the effects of cyanidin-3-o-glucoside (C3G), a monomer of anthocyanin, on UVA-induced damage in primary human dermal fibroblasts (HDFs), and we identify possible mechanisms underlying the protective effects of this compound., Methods: Primary HDFs were pretreated with 80 μmol/L C3G for 2 hours and UVA irradiated at 12 J/cm 2 . The cells were then incubated with 80 μmol/L C3G for 12 hours after irradiation. HDFs were randomly divided into control, UVA treatment, C3G, and UVA treatment plus C3G pretreatment groups., Results: C3G increased the cell viability of primary HDFs and decreased UVA-induced ROS production and apoptosis rate. Compared to the UVA group, the UVA plus pretreatment with C3G group displayed increased Bcl-2 expression and Bcl-2/Bax ratio, decreased cleaved caspase-3 and p-P38 levels, and increased ERK phosphorylation; no significant effect on p-JNK levels was observed., Conclusion: C3G reduced UVA-induced HDF oxidative damage and apoptosis, likely be related to the down-regulation of p-P38, up-regulation of ERK protein phosphorylation., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Neural stem cells (NSCs) transplanted is one of the hottest research to treat Alzheimer's disease (AD), but cholinergic neurons from stem cells were also susceptible to cell death which Heat shock protein 70 (HSP70) was affirmed to reverse. Related to cognitive impairment, cholinergic nervous cells should be investigated and ginsenoside Rg1 (G-Rg1) was considered to increase them. We chose tert-butyl hydroperoxide (t-BHP) damage model to study in vitro. Functional properties of our recombination plasmid pEGFP-C2-HSP70 were affirmed by SH-SY5Y cells. To opposite the transitory appearance of HSP70, NSCs used as the vectors of HSP70 gene overexpressed HSP70 for at least 7 days in vitro. After transfection for 3 days, G-Rg1 pretreatment for 4 hours, and coculture for 3 days, the expression of acetylcholinesterase (ChAT), synaptophysin, and the ratio of NeuN and GFAP were assessed by western blot; Morphological properties were detected by 3D reconstruction and immunofluorescence. ChAT was markedly improved in the groups contained G-Rg1. In coculture system, the ratio of neurons/astrocytes and the filaments of neurons were increased; apoptosis cells were decreased, compared to monotherapy (P < 0.05). In conclusion, we demonstrated that, as a safe cotreatment affirmed in vitro, overexpression of HSP70 in NSCs plus G-Rg1 promoted nervous cells regeneration from chronic oxidative damage.

Background/Purpose: Ultraviolet (UV) A (315‐400 nm) is the UV light that most frequently reaches the Earth's surface and can penetrate the epidermis through to the dermis, causing various issues, including skin aging and skin cancer. The results of our previous studies have shown that the flavonoid monomer cyanidin‐3‐o‐glucoside (C3G) can effectively inhibit primary human dermal fibroblast (HDF) oxidative damage and apoptosis caused by UVA radiation. Many flavonoids can regulate the level of autophagy. However, whether C3G inhibits UVA‐induced oxidative damage to primary HDFs by regulating autophagy levels remains unclear. Methods and Results: In this study, we used different doses (0‐12 J/cm2) of UVA to irradiate cells and showed that the expression levels of autophagy‐related gene 5 (Atg5) and microtubule‐associated protein 1 light chain 3 (LC3)‐II in primary HDFs first increased and then decreased. The expression of Atg5 and LC3‐II was significantly decreased under 12 J/cm2 (light‐damage model). C3G increased the levels of Atg5 and LC3‐II. Primary HDFs were pretreated with C3G, followed by treatment with the autophagy inhibitor 3‐methyladenine (3‐MA) after 12 J/cm2 UVA irradiation. The inhibitory effects of C3G on morphological changes, oxidative damage, and apoptosis in primary HDFs induced by UVA were significantly decreased. Conclusion: C3G can inhibit UVA‐induced damage to primary HDFs by inducing autophagy. These results provide a theoretical basis for the application of natural compounds to resist light damage to the skin in the future. [ABSTRACT FROM AUTHOR]