Considerable studies indicate huperzine A is a promising natural product to suppress neuronal damages induced by β-amyloid (Aβ), a key pathogenic event in the Alzheimer’s disease (AD). As an extension, the present study for the first time explored whether the beneficial profiles of huperzine A against oligomeric Aβ42 induced neurotoxicity are associated with the accumulation and detrimental function of intraneuronal/mitochondrial Aβ, on the basis of the emerging evidence that intracellular Aβ is more relevant to AD progression as compared with extracellular Aβ. Huperzine A treatment was shown to significantly attenuate the neurotoxicity of oligomeric Aβ42, as demonstrated by increased neuronal viability. Interestingly, our results proved that exogenous Aβ42 could accumulate intraneuronally in a dose- and time-dependent manner, while huperzine A treatment markedly reduced the level of intracellular Aβ42. Moreover, huperzine A treatment rescued mitochondrial dysfunction induced by oligomeric Aβ42, including adenosine triphosphate (ATP) reduction, reactive oxygen species (ROS) overproduction and membrane potential depolarization. Further study demonstrated that huperzine A also significantly reduced the level of Aβ42 in the mitochondria-enriched subcellular fractions, as well as the Aβ42 fluorescent signals colocalized with mitochondrial marker. This study indicates that interfering intracellular Aβ especially mitochondrial Aβ accumulation, together with ameliorating Aβ-associated mitochondrial dysfunction, may contribute to the protective effects of huperzine A against Aβ neurotoxicity. Above results may shed more light on the pharmacological mechanisms of huperzine A and provide important clues for discovering novel therapeutic strategies for AD.

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Nanoparticles of MgO were successfully prepared in Triton X-100/n-hextnol/cyclohexane/water W/O microemulsion system. Basic preparation conditions were determined. TG-DTA showed that the proper calcination temperature was 450 oC. The nanoparticles were characterized by XRD and IR measurements in order to determine the crystal phase and component of the products. The morphological feature of the nanoparticles has been investigated by TEM. The result of XRD pattern demonstrated that the particles were exactly indexed to a cubic rock salt structure of MgO. There are no organic or inorganic impurities appeared after 450 oC calcination. The result of TEM showed that the MgO nanoparticles were spherical and uniform. The UV-visible spectra demonstrated the phenomenon of absorption blue shift, which is the evidence of quantum confinement effect, with the decrease of water/surfactant(R) value. Average size of the nanoparticles increased with increasing R value.

Ni/Al hydrotalcite-derived oxides (Ni/Al LDOs) prepared with various Ni/Al ratios at 300°C were used to investigate the removal of gaseous hydrogen cyanide (HCN). The results showed that Ni/Al LDOs exhibited outstanding performance for HCN removal, especially LDO with a Ni/Al ratio of 4 due to the formation of Ni/Al metal oxides (NiO and Al 2 O 3) and the disappearance of hydrotalcite after 300°C calcination. Comparison of LDO with other Ni/Al ratios, LDO with a Ni/Al ratio of 4 had a higher surface area of 178 mg 2 /g and smaller mesopores of 5.46 nm as determined by nitrogen adsorption/ desorption isotherms. CO 2 temperature programmed desorption (CO 2-TPD) experiments revealed that the weak basic sites and Ni-O group of the LDO with a Ni/Al ratio of 4 dominated HCN removal. Fourier-transform infrared (FTIR) spectra analysis demonstrated that adsorbed CN was converted into [Ni(CN) 4 ] 2 , implying the occurrence of chemical adsorption. Further experiments found that a relatively low concentration water vapor can promote the removal e ciency of HCN on Ni/Al LDOs, while the inhibiting e ect on the removal e ciency of HCN was observed in the presence of water vapor with high concentration due to its competitive adsorption e ect. These ndings are helpful for the development of innovative technology for the removal of HCN, and also provide a new treatment strategy for HCN based on Ni/Al LDOs.