The role of quercetin on the survival of neuron-like PC12 cells and the expression of α-synuclein

Both genetic and environmental factors are important in the pathogenesis of Parkinson＇s disease. As α-synuclein is a major constituent of Lewy bodies, a pathologic hallmark of Parkinson＇s disease, genetic aspects of α-synuclein is widely studied. However, the influence of dietary factors such as quercetin on α-synuclein was rarely studied. Herein we aimed to study the neuroprotective role of quercetin against various toxins affecting apoptosis, autophagy and aggresome, and the role of quercetin on α-synuclein expression. PC12 cells were pre-treated with quercetin（100, 500, 1,000 μM） and then together with various drugs such as 1-methyl-4-phenylpyridinium（MPP＋; a free radical generator）, 6-hydroxydopamine（6-OHDA; a free radical generator）, ammonium chloride（an autophagy inhibitor）, and nocodazole（an aggresome inhibitor）. Cell viability was determined using a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltertazolium bromide（MTT） assay. Apoptosis was detected by annexin V-fluorescein isothiocyanate and propidium iodide through the use of fluorescence activated cell sorter. α-Synuclein expression was detected by western blot assay and immunohistochemistry. The role of α-synuclein was further studied by knocking out α-synuclein using RNA interference. Cell viability increased at lower concentrations（100 and 500 μM） of quercetin but decreased at higher concentration（1,000 μM）. Quercetin exerted neuroprotective effect against MPP＋, ammonium chloride and nocodazole at 100 μM. MPP＋ induced apoptosis was decreased by 100 μM quercetin. Quercetin treatment increased α-synuclein expression. However, knocking out α-synuclein exerted no significant effect on cell survival. In conclusion, quercetin is neuroprotective against toxic agents via affecting various mechanisms such as apoptosis, autophagy and aggresome. Because α-synuclein expression is increased by quercetin, the role of quercetin as an environmental factor in Parkinson＇s disease pathogenesis needs further investigation.

Apoptosis of Lewis Lung Carcinoma Cells Induced by Microwave via p53 and Proapoptotic Proteins In vivo

Background： Microwave therapy is a minimal invasive procedure and has been employed in clinical practice for the treatment of various types of cancers. However, its therapeutic application in non-small-cell lung cancer and the underlying mechanism remains to be investigated. This study aimed to investigate its effect on Lewis lung carcinoma （LLC） tumor in vivo. Methods： Fifty LLC tumor-bearing C57BL/6 mice were adopted to assess the effect of microwave radiation on the growth and apoptosis of LLC tumor in vivo. These mice were randomly assigned to 10 groups with 5 mice in each group. Five groups were treated by single pulse microwave at different doses for different time, and the other five groups were radiated by multiple-pulse treatment of a single dose. Apoptosis of cancer cells was determined by terminal deoxynucleotidyl transferase dUTP nick-end labeling assay. Western blotting was applied to detect the expression of proteins. Results： Single pulse of microwave radiation for 5 min had little effect on the mice. Only 15-min microwave radiation at 30 mW/cm2 significantly increased the mice body temperature （2.20 ± 0.82）℃ as compared with the other groups （0.78 ± 0.29 ℃, 1.24 ± 0.52 ℃, 0.78 ± 0.42 ℃, respectively）, but it did not affect the apoptosis of LLC tumor cells significantly. Continous microwave radiation exposure, single dose microwave radiation once per day for up to seven days, inhibited cell division and induced apoptosis of LLC tumor cells in a dose- and duration-dependent manner. It upregulated the protein levels of p53, Caspase 3, Bax and downregulated Bcl-2 protein. Conclusions： Multiple exposures of LLC-bearing mice to microwave radiation effectively induced tumor cell apoptosis at least partly by upregulating proapoptotic proteins and downregulating antiapoptotic proteins. Continuous radiation at low microwave intensity Ibr a short time per day is promising in treating non-small-cell lung cancer.

The efficacy of the inhalation of an aerosolized Group A streptococcal preparation in the treatment of lung cancer

Objective： To observe the efficacy of the inhalation of an aerosonzeo group ~ sueloto^u v / preparation in treating orthotopic lung cancer in mouse models and assess the feasibility, safety, and effectiveness of this administration mode for lung cancer. Methods： Lewis lung carcinoma （LLC） cell strains were administered via intrathoracic injection to establish orthotopic lung cancer mouse models. After the tumor-bearing models were successfully established, as confirmed by computed tomography, the mice were administered by inhalation with an aerosolized GAS preparation （GAS group） or aerosolized normal saline （control group）. The anti-tumor effect of the aerosolized GAS preparation was evaluated histologically; meanwhile, the survival and quality of life were compared between these two groups. Results： The aerosolized GAS preparation showed remarkably anti-tumor effect, causing the necrosis of the orthotopic lung cancer cells in tumor-bearing mice. Furthermore, mice in the GAS group had significantly better qualitT of life and longer survival than those in control group. Conclusions： The inhalation of aerosolized GAS preparation may be a feasible, safe and effective solution for lung cancer

Kinetic study on reactive extraction for chiral separation of phenylsuccinic acid enantiomers

The kinetics of the extraction of phenylsuccinic acid(PSA) enantiomers by hydroxypropyl-β-cyclodextrin(HP-β-CD) in a modified Lewis cell was studied,in which HP-β-CD dissolved in 0.1 mol L-1 NaH2PO4/H3PO4 buffer solution(pH = 2.5) was selected as the chiral extractant.PSA enantiomers were extracted from organic phase to aqueous phase in the extraction module.The theory of extraction accompanied by a chemical reaction has been used to obtain the intrinsic kinetics of this extraction module.The different parameters affecting the extraction rate such as agitation speed,interfacial area,initial concentration of PSA enantiomers in organic phase as well as HP-β-CD concentration in aqueous phase were separately studied.The experimental results demonstrate that the extraction reactions are fast.The reactions were found to be first order with respect to PSA and second order with respect to HP-β-CD with forward rate constants of 3.4 × 10-2 m6 mol-2 s-1 for R-PSA and 9.96 × 10?3 m6 mol-2 s-1 for S-PSA.These data will be useful in the design of extraction processes.