Role of ataxia-telangiectasia mutated gene in maintaining quiescence of neural stem cell from subgranular zone of mouse hippocampus / 解剖学报

Objective To investigate the role of ataxia-telangiectasia mutated gene (ATM) in maintaining quiescence of neural stem cells (NSCs) from subgranular zone (SGZ) of hippocampal dentate gyms in mice. Methods We constructed 1-month-old and 4-month-old mice ATM knockout mice, with 12 mice in each group. The NSCs in SGZ of ATM knockout mice were isolated, cultured and identified in vitro. The proliferation ability of NSCs in SGZ of 1-month-old ATM

Change of ROCK1 Gene Expression Level in Patients with Acute Lymphoblastic Leukemia and Its Clinical Significance / 中国实验血液学杂志

OBJECTIVE@#To investigate the expression change of ROCK1 gene in patients with acute lymphoblastic leukemia (ALL) and its prognostic significance.@*METHODS@#Sixty patients with ALL were selected in our hospital from April 2017 to April 2018, and 60 healthy persons subjected to physical examination were selected as control. The venous blood was taken from the subjects, and then the mononuclear cells were separated. The ROCK1 gene expression level in the samples was detected by RT-PCR, and the expression level of ROCK1 protein was detected by Western blot. The correlation between ROCK1 gene expression and clinical characteristics of ALL patients was analyzed by using statistical methots.@*RESULTS@#The RT-PCR showed that the relative expression level of ROCK1 gene in ALL patients was 1.37 (1.28-1.46), which was significantly higher than that in the control group (P0.05). The standard risk ratio of B-ALL and T-ALL patients with low ROCK1 expression was significantly higher than that in patients with high ROCK1 expression (P<0.05). The high risk ratio of B-ALL and T-ALL patients with low ROCK1 expression was significantly lower than those with high ROCK1 expression (P<0.05). The ratio of CR in the group with low ROCK1 expression patients was significantly higher than that in patients with high ROCK1 expression (P<0.05). The Relapse rate of the group with low ROCK1 expression was significantly lower than that of the group with high ROCK1 expression (P<0.05). Kaplan-Meier survival analysis showed that OS and DFS in ALL patients with low ROCK1 expression were superior to those in ALL patients with high ROCK1 expression (P<0.05). Multiple factor Cox regression analysis showed that age and ROCK1 gene were independent influencing factors for OS (P<0.05); leukocyte count and ROCK1 gene were independent influencing factors for DFS (P<0.05).@*CONCLUSION@#The expression level of ROCK1 gene in ALL patients is high, which may stimulate the genesis of ALL, and the down-regulation of ROCK1 gene expression may help improve the therapeutic effect for ALL patients.

The role and mechanism of NADPH oxidase in leptin-induced reactive oxygen species production in hepatic stellate cells / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate whether or not NADPH oxidase (NOX) participates in leptin-induced reactive oxygen species (ROS) production in hepatic stellate cells (HSC) and to explore the possible mechanism.</p><p><b>METHODS</b>HSC-T6 cells (rat hepatic stellate cells line) were divided into nine groups: Group1: leptin (100 ng/ml) treated; Group2-6: leptin treated together with inhibitors that block different ROS-producing systems: diphenylene-iodonium (DPI) (20 micromol/L), Rotenone (20 micromol/L), Metyrapone (250 micromol/L), Allopurinol (100 micromol/L) and Indomethacin(100 micromol/L); Group7: leptin treated together with Janus kinase (JAK) inhibitor AG490 50 micromol/L; Group8: normal control group (treated DMEM with 0.1% DMSO); Group9: negative control group (untreated). Intracellular ROS levels were measured with dichlorodihydrofluorescein diacetate (DCFH-DA) dye assay by Fluorescence microscope and/or flow cytometry. NOX activity was analyzed by using spectrophotometer to calculate the absorbance of NADPH. The mRNA levels of Rac1 and p22Phox were evaluated by RT-PCR.</p><p><b>RESULTS</b>(1) Leptin increased significantly the ROS production as compared to normal control group (92.91+/-4.19 vs.27.56+/-6.27, P<0.01) in HSC-T6 cells. Both the NADPH oxidase inhibitor DPI and AG490 (50 micromol/L) blocked the ROS production, inhibitors of other ROS producing systems had no significant effect on ROS production induced by lepin (P is more than 0.05). (2) Leptin treated HSC-T6 cells for 1 hour up-regulated the NOX activity significantly compared with that in normal control group [(1.90+/-0.22) pmol.min(-1).mg(-1) vs. (0.76+/-0.06) pmol.min(-1).mg(-1), P<0.05]. Furthermore, the NOX activity increased after being treated with leptin for 12 hours and 24 hours than being treated for 1 hour. Leptin-induced up-regulation of NOX activity was inhibited by pretreatment with DPI or AG490. (3) The RT-PCR results indicated that mRNA expressions of Rac1 and p22Phox in HSC-T6 cells with 12 hours of leptin stimulation increased significantly as compared with normal control group (0.41+/-0.13 vs 0.14+/-0.08, 0.45+/-0.12 vs 0.20+/-0.08, all P<0.05), while the DPI and AG490 had no effect on the mRNA expressions of Rac1 and p22Phox.</p><p><b>CONCLUSION</b>NOX is the main cellular source of the reactive oxygen species (ROS) generated by HSCs in response to leptin stimulation. The mechanism is probably that leptin can directly activate NOX through JAK signal transduction and hence induce the expression of NOX subunit to promote the activity of NOX which generates considerable ROS in HSC.</p>