The Impacts of Simulated Microgravity on Rat Brain Depended on Durations and Regions / 生物医学与环境科学（英文）

OBJECTIVE@#To explore the dynamic impacts of simulated microgravity (SM) on different vital brain regions of rats.@*METHODS@#Microgravity was simulated for 7 and 21 days, respectively, using the tail-suspension rat model. Histomorphology, oxidative stress, inflammatory cytokines and the expression of some key proteins were determined in hippocampus, cerebral cortex and striatum.@*RESULTS@#21-day SM decreased brain derived neurotrophic factor and induced neuron atrophy in the cerebral cortex. Strong oxidative stress was triggered at day 7 and the oxidative status returned to physiological level at day 21. Inflammatory cytokines were gradually suppressed and in striatum, the suppression was regulated partially through c-Jun/c-Fos.@*CONCLUSION@#The results revealed that the significant impacts of SM on rat brain tissue depended on durations and regions, which might help to understand the health risk and to prevent brain damage for astronauts in space travel.

Effect of androgen receptor on IgG expression, proliferation and migration of prostate cancer cells in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of androgen receptor (AR) on IgG protein expression and the proliferation and migration of prostate cancer cells.</p><p><b>METHODS</b>Western blotting was used to detect the expression of AR protein and IgG in androgen-dependent prostate cancer LNCap cells and castration-resistant prostate cancer PC-3 cells. In AR-overexpressing cells (PC-3-AR cells) established by transfecting PC-3 with AR gene (pCDNA3.1) and LNCap cells with small interfering RNA-mediated AR silencing (LNCap-siAR cells) were analyzed for expressions of AR protein and IgG with Western blotting; the expression of IgG mRNA was detected by Q-PCR, and the cell proliferation and migration were assessed with MTT assay and wound healing assay, respectively.</p><p><b>RESULTS</b>Compared with PC-3 cells, LNCap cells expressed a higher level of AR protein and a lower level of IgG (P<0.05). PC-3-AR cells showed attenuated proliferation and migration with a lowered expression of IgG (P<0.01), while LNCap-siAR cells showed enhanced proliferation and migration with increased expression of IgG (P<0.01).</p><p><b>CONCLUSION</b>The expression of AR is inversely correlated with IgG and is associated with the proliferation and migration of prostate cancer cells in vitro.</p>

Suitable oxygen concentration for rat model's hypoxic preconditioning / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To study the suitable oxygen concentration in hypoxic preconditioning.</p><p><b>METHODS</b>Short-term and long-term intermittent hypoxia modes were designed and the effects of various oxygen concentrations on body weight, blood oxygen saturation, swimming capability were analyzed.</p><p><b>RESULTS</b>The rate of body weight gain in rat model decreased gradually when exposed to hypoxia environment for long time. When the concentration of oxygen changed from 15% to 8%, accompanied with the decreasing of oxygen concentration, a platform was observed in blood oxygen saturation of rat model after hypoxic preconditioning training. Rat swimming capability improved significantly. After trained in 10% hypoxia environment, the swimming capability of kunming mice improved obviously.</p><p><b>CONCLUSION</b>Proper level of hypoxic preconditioning training could improve hypoxia tolerance and enhance the rat sport capability significantly. 15%-10% oxygen concentration range could be regarded as a helpful effective area for hypoxic preconditioning, 10% oxygen concentration might be the eligible concentration for hypoxic preconditioning training.</p>

Iron contributes to the formation of catechol isoquinolines and oxidative toxicity induced by overdose dopamine in dopaminergic SH-SY5Y cells / 神经科学通报·英文版

<p><b>OBJECTIVE</b>The selective loss of dopaminergic neurons in Parkinson's disease is suspected to correlate with the increase of cellular iron, which may be involved in the pathogenesis of PD by promotion of oxidative stress. This research investigated dopamine-induced oxidative stress toxicity contributed by iron and the production of dopamine-derived neurotoxins in dopaminergic SH-SY5Y cells.</p><p><b>METHODS</b>After the SH-SY5Y cells were pre-incubated with dopamine and Fe2+ for 24 h, the cell viability, hydroxyl radical, melondialdehyde, cell apoptosis, and catechol isoquinolines were measured by lactate dehydrogenase assay, salicylic acid trapping method, thiobarbuteric acid assay, Hoechst 33258 staining and HPLC-electrochemical detection (HPLC-ECD), respectively.</p><p><b>RESULTS</b>(1) Optimal dopamine (150 micromol/L) and Fe2+ (40 or 80 micromol/L) significantly increased the concentrations of hydroxy radicals and melondialdehyde in SH-SY5Y cells. (2) Induction with dopamine alone or dopamine and Fe2+ (dopamine/Fe2+) caused cell apoptosis. (3) Compared with untreated cells, the catechol isoquinolines, salsolinol and N-methyl-salsolinol in dopamine/Fe2+-induced cells were detected in increasing amounts.</p><p><b>CONCLUSION</b>Due to dopamine/Fe2+-induced oxidative stress similar to the state in the parkinsonian substantia nigra neurons, dopamine and Fe2+ impaired SH-SY5Y cells could be used as the cell oxidative stress model of Parkinson's disease. The catechol isoquinolines detected in cells may be involved in the pathogenesis of Parkinson's disease as potential neurotoxins.</p>

Determination of astragulin in Thesium chinese by RP-HPLC / 中国中药杂志

<p><b>OBJECTIVE</b>To establish a determination method of astragulin in Thesium chinese.</p><p><b>METHOD</b>RP-HPLC analytical method was established using a Polaris C18 column and acetonitrile-water (23:77) as the mobile phase, with a flow rate of 10 mL x min(-1), detected at 346 nm. The method of sample is refluxing exation by 50% alcohol for 2 times.</p><p><b>RESULT</b>The content of astragulin was from 0. 120% to 0. 155%, in different groups of T. chinese collected from the same location.</p><p><b>CONCLUSION</b>The method was validated to show convenient and reliable.</p>