Mechanism of Triclosan in the Treatment of Nonalcoholic Fatty Liver Disease Based on Network Pharmacology / 中国医学科学院学报

Objective To explore the potential targets of triclosan in the treatment of nonalcoholic fatty liver disease(NAFLD) and to provide new clues for the future research on the application of triclosan. Methods The targets of triclosan and NAFLD were obtained via network pharmacology.The protein-protein interaction network was constructed with the common targets shared by triclosan and NAFLD.The affinity of triclosan to targets was verified through molecular docking.Gene ontology(GO) annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment were carried out to analyze the key targets and the potential mechanism of action.NAFLD model was established by feeding male C57BL/6J mice with high-fat diet for 12 weeks.The mice were randomly assigned into a model group and a triclosan group [400 mg/(kg·d),gavage once a day for 8 weeks].The hematoxylin-eosin(HE) staining was used for observation of the pathological changes and oil red O staining for observation of fat deposition in mouse liver.Western blotting was employed to detect the protein level of peroxisome proliferator-activated receptor alpha(PPARα) in the liver tissue. Results Triclosan and NAFLD had 34 common targets,19 of which may be the potential targets for the treatment,including albumin(ALB),PPARα,mitogen-activated protein kinase 8(MAPK8),and fatty acid synthase.Molecular docking predicted that ALB,PPARα,and MAPK8 had good binding ability to triclosan.KEGG pathway enrichment showcased that the targets were mainly enriched in peroxisome proliferator-activated receptor signaling pathway,in which ALB and MAPK8 were not involved.Triclosan alleviated the balloon-like change and lipid droplet vacuole,decreased the lipid droplet area,and up-regulated the expression level of PPARα in mouse liver tissue. Conclusion PPARα is a key target of triclosan in the treatment of NAFLD,which may be involved in fatty acid oxidation through the peroxisome proliferator activated receptor signaling pathway.

Effects of DNA polymerase beta on the genotoxicity and genetic instability induced by benzo(a)pyrene / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the effects of DNA polymerase β expression level on the genotoxicity and genetic instability induced by benzo(a)pyrene (BaP),and provide experimental the basis for further study on the carcinogenic molecular mechanism of BaP.</p><p><b>METHODS</b>Three kinds of cell lines with the identical genetic background, polβ wild-type cells (polβ+/+), polβ null cells (polβ-/-) and polβ overexpression cells (polβ oe) were applied as cellular models. The oxidative damage, genotoxicity and genetic instability induced by BaP were analyzed by using different methods respectively.</p><p><b>RESULTS</b>Cell viability and colony forming ability of 3 kinds of cell lines exposed to BaP decreased with BaP. After treated with 5 and 20 µmol/L concentration of BaP, fluorescence intensity of polβ-/- cell line was significantly higher than that of other two cell lines (P < 0.05). When treated with 5.00 µmol/L and 20.00 µmol/L concentration of BaP, the SOD activities (76.56 ± 2.84 and 62.78 ± 4.28 U/mg pro) of polβ-/- cell line were significantly lower than that (84.85 ± 3.59) of control group and those (85.21 ± 3.20 and 76.90 ± 3.38 U/mg pro) of polβ+/+ cell line. In 20.00 µmol/L BaP group. SOD activity (82.59 ± 4.64 U/mg pro) of polβ oe cell line was lower than that (88.58 ± 6.77 U/mg pro) of control but higher than that of polβ+/+ cell line (P < 0.05). In 1.25, 5.00 and 20.00 µmol/L concentration BaP groups, the micronucleus rates of polβ-/- cell line were much higher than those of polβ+/+ cell line (P < 0.05). In 5.00 and 20.00 µmol/L concentration BaP groups, the micronucleus rates of polβ oe cell line were significantly lower than those of polβ+/+ line (P < 0.05). In 5.00 and 20.00 µmol/L concentration BaP groups, HPRT gene mutation frequencies (26.16 × 10(-6) and 37.51 × 10(-6); 27.68 × 10(-6) and 38.63 × 10(-6)) in polβ-/- cells and polβ oe cells were significantly higher than those (19.76 × 10(-6) and 24.78 × 10(-6)) of polβ+/+ cells (P < 0.05).</p><p><b>CONCLUSION</b>Polβ could play a role in protecting the cells from the genotoxicity and genetic instability induced by BaP, and the normal expression level of polβ was indispensable for maintaining genome stability.</p>

Effect of DNA polymerase beta on apoptosis and mitochondrial membrane potential induced by hydroquinone, a metabolite of benzene / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the effect and mechanism of DNA polymerase β expression level on cell apoptosis and mitochondrial membrane potential induced by hydroquinone.</p><p><b>METHODS</b>Polβ wild-type cells (polβ+/+), polβ overexpressed cells (polβ oe) and polβ null cells (polβ-/-) were applied as a model cell system, The effect of cell apoptosis and mitochondrial membrane potential induced by different doses of hydroquinone were analyzed by flow cytometry. The ROS and ·OH assay kit were used to examine the cellular ROS and ·OH level. The activity of cellular SOD and GSH-Px were tested by Chemiluminescence method after exposed to different concentrations of hydroquinone.</p><p><b>RESULTS</b>With the dose of hydroquinone increased, the rate of apoptosis and falling of mitochondrial membrane potential (ΔΨm) in cells were increased compared with the control. When compared with polβ+/+ cells, the rate of apoptosis in polβ-/- cells exposed to 20.00, 40.00, 80.00 µmol/L hydroquinone increased and the rate of apoptosis in polβ oe cells exposed to 10.00, 20.00, 40.00, 80.00 µmol/L hydroquinone decreased (P < 0.05). Compared with polβ+/+ cells (20.60% ± 0.57%, 37.95% ± 0.64%, 44.50% ± 1.27%, 57.55% ± 1.06%), the rate of cell which undergone mitochondrial depolarization in polβ-/- cells treated with 10.00, 20.00, 40.00, 80.00 µmol/L hydroquinone (33.60% ± 1.55%, 46.05% ± 1.77%, 52.75% ± 2.05%, 75.20% ± 0.56%) increased. The rate of cell which undergone mitochondrial depolarization in polβ oe cells exposed to 10.00, 20.00, 40.00, 80.00 µmol/L hydroquinone (16.05% ± 1.20%, 29.80% ± 1.21%, 35.15% ± 1.06%, 53.80% ± 0.85%) decreased (P < 0.05). When compared with polβ+/+ cells, fluorescent intensity of polβ-/- cells treated with different dosages of hydroquinone increased, while which of polβ oe cells decreased (P < 0.05). Compared with polβ+/+ cells, ·OH level of polβ-/- cells treated with 20.00, 40.00 µmol/L hydroquinone significantly enhanced, while which of polβ oe cells decreased sharply (P < 0.05). Under the same concentrations of hydroquinone, the activity of SOD and GSH-Px were decreased most rapidly in polβ-/- cells. The activity of SOD and GSH-Px in polβ oe cells decreased slower than in the polβ-/- cells.</p><p><b>CONCLUSION</b>Hydroquinone could induced apoptosis by the generation of ROS and decrease of ΔΨm; polβ could protect cells from apoptosis induced by hydroquinone through decrease of ROS level and depolarization of mitochondria.</p>

Effects of hydroquinone on expression of human 8-oxo-guanine DNA glycosylase mRNA in human A549 lung adenocarcinoma cell strains / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effects of hydroquinone (HQ) on reactive oxygen species (ROS) generation, antioxydase activities and the expression of human 8-oxo-guanine DNA glycosylase (hOGG1) mRNA in human A549 lung adenocarcinoma cell strains.</p><p><b>METHODS</b>A549 cells were treated with different concentrations of HQ. Cell survival was determined by methyl thiazolyl tetrazolium (MTT). Changes of ROS were detected by fluorescent probe. The contents of malonaldehyde and activities of antioxydase were determined through colorimetry. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to assess the level of hOGG1 mRNA.</p><p><b>RESULTS</b>With the increased concentration of HQ, the findings were as follows. (1) The absorbance value of A549 cell decreased. There was significant difference between 160 micromol/L (0.584+/-0.098) and 320 micromol/L (0.328+/-0.066) of HQ (q=5.56 and 9.07, P<0.05) with the control group (0.989+/-0.150), and the cell survival rate were less than 80%. (2) The ROS in A549 cell increased. 40 micromol/L (39.80+/-4.15) and 80 micromol/L (101.99+/-9.45) had statistical significance (q=10.74 and 30.32, P<0.05) with the control group (5.71+/-0.50). (3) It was found that the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) decreased and malonaldehyde (MDA) increased. Compared with the control group [(25.62+/-0.28) U/mg prot and (38.97+/-2.61) U/mg prot], the activities of SOD and GSH-Px had a significant decrease (q=12.17 and 8.78, P<0.05) in 80 micromol/L [(22.93+/-0.56) U/mg prot and (25.60+/-2.31) U/mg prot]. And MDA had a significant increase (q=10.90 and 15.49, P<0.05) in 40 micromol/L [(1.07+/-0.01) nmol/mg prot] and 80 micromol/L [(1.19+/-0.08) nmol/mg prot] as compared with the control group [(0.77+/-0.04) nmol/mg prot]. The decrease of SOD (r=-0.95, F=20.00, P=0.04) and GSH-Px activities (r=-0.99, F=115.48, P=0.01) and the increase of MDA contents (r=0.96, F=21.31, P=0.04) all had a dose-response relationship. (4) RT-PCR results showed that the expression of hOGG1 mRNA decreased. The significant difference was observed between the expression of hOGG1 mRNA in 80 micromol/L (0.478+/-0.017) (q=11.70, P<0.05) with the control group (0.715+/-0.038).</p><p><b>CONCLUSION</b>This study suggests that HQ could induce oxidative damage and changes of the expression of hOGG1 mRNA in A549 cells.</p>

Effect of down-regulated hOGG1 gene expression on cytotoxicity and genotoxicity of hydroquinone / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the effects of down- regulated hOGG1 gene expression on cytotoxicity and genotoxicity of hydroquinone.</p><p><b>METHODS</b>A549 cells and A549-R cells with down- regulated hOGG1 gene were treated with different concentrations of hydroquinone (0, 5, 10, 20, 40 and 80 μmol/L). The cellular sensitivity and contents of ROS were measured by MTT assay and fluorescence method, respectively. The chromosome damage was measured by micronucleus test. The DNA damage and repair were examined using comet assay in both cells.</p><p><b>RESULTS</b>The cell viability decreased with increasing concentration of hydroquinone. The IC₅₀ of hydroquinone was 160.49 and 228.42 μmol/L in hOGG1 deficient A549-R cell and in A549 cell respectively (P < 0.05). When the dose of hydroquinone reached 5 micromol/L and above, the contents of ROS and the rate of micronucleated cells in A549-R cells were significantly higher than in A549 (P < 0.05) cells. At the same time, the comet rate and OTM in A549-R cells were significantly higher compared with A549 cells at 5 micromol/L and above in a dose-response way (P < 0.05). Furthermore, in DNA repair assay, A549-R cells with down- regulated hOGG1 gene were more difficult to repair than A549 cells. In A549-R cells, the comet rate and OTM reduced significantly until after 2 h repair time and even after 3 h the DNA damage was not repaired completely.</p><p><b>CONCLUSION</b>Oxidative damage may be one of the toxicological mechanisms of hydroquinone, and hOGG1 deficiency could increase sensitivity of A549-R cells to hydroquinone.</p>

Molecular epidemiological study on oxidative DNA damage among Hasake ethnic migrants in Shenzhen / 中华流行病学杂志

objective To explore the relationship of migration and oxidative DNA damage by comparative study of oxidative DNA damage effects on people with difierent years of migration among Xinjiang Hasake ethnecity in Shenzhen.Methods Sixty Hasake residents in Shenzhen were selected,and were divided into three groups(n=20)according to the years of migration.Major changes of their life style were investigated.8-hydroxy-2'-deoxyguanosine(8-OH-dG)levels in urine were analyzed,and comet assay of peripheral blood lymphocytes conducted.Results When comparing with the group having a shorter than 1 year of stay,a significant decrease of oliveive tail moment and tail/head length in comet assay in the＞3 years group(P＜0.05)was observed 8-OH-dG level decreased significantly in 1-3 years group (P＜0.05)and＞3 years group(P＜0.01).Conclusion Our results suggested that life style changes which related to migration might reduce DNA damage in Hasake nationalities.

Effects and mechanism of lutein on apoptosis of esophageal carcinoma EC9706 cells / 中国中药杂志

<p><b>OBJECTIVE</b>To study the effects of lutein on apoptosis and its mechanism.</p><p><b>METHOD</b>The cells of human esophageal carcinoma EC9706 were grown in RPMI medium containing 10% bovine serum and were treated with lutein at 100 microg x mL(-1) concentration. Flow cytometry was employed to investigate the effects of lutein on cell apoptosis of EC9706 cells. Histochemistry was performed to determine apoptosis-related protein expresion.</p><p><b>RESULT</b>Flow cytometry analyses revealed that lutein increased EC9706 cell apoptosis ratio when treated with lutein 100 microg x mL(-1) at 96 h. Lutein decreased the expression of Bcl-2 protein and increased the expression of Bax protein in EC9706 cells.</p><p><b>CONCLUSION</b>Lutein could inhibit mitosis and stimulate apoptosis of EC9706 cells. The apoptotic effect may result from the down-regulation of expression of Bcl-2 and up-regulation expression of Bax.</p>