A novel calcium phosphate cement pre-loaded with chitosan and small molecule adenosine for repairing large cranial defects in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the effect of a novel biomaterial in repairing large cranial defects in rats.</p><p><b>METHODS</b>Eighteen SD rats were used to establish rat modes of large cranial defect (8 mm in diameter). The rat models were randomized into 3 groups and the cranial defects were repaired using different scaffold materials, namely CPC paste prepared with distilled water (CPC control group), CPC paste mixed with 10% chitosan (CPC/CN group), or CPC paste with 10% chitosan and 300 mg adenosine (CPC/CN/AD group). The defects were examined 12 weeks after the surgery with X-ray, CT, HE staining and quantitative assessments.</p><p><b>RESULTS</b>X-ray showed that the defect was repaired in all the groups. The fracture line became obscure and the defects were almost fully repaired by regenerated bone tissues in CPC/CN/AD group, which was consistent with CT findings. In all the 3 groups, HE staining revealed the presence of new bones in the defects and new vessels in and around the new bones without inflammatory cells. The new bone area was significantly greater in CPC/CN/AD group than in CPC/CN group and CPC control group (P<0.05). The new vessel density was the highest in CPC/CN/AD group (P>0.05) but similar between CPC/CN group and CPC control group (P>0.05).</p><p><b>CONCLUSION</b>This novel calcium phosphate cement pre-loaded with chitosan and small molecule adenosine can better promote bone regeneration than calcium phosphate cement for repairing large bone defects to serve as a good replacement material for bone regeneration.</p>

Effects of trichloroethylene on hepatotoxicity in cytochrome 2E1-silenced hepatocytes / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To prepare cytochrome (CYP)2E1-silenced hepatocytes by lentivirus-mediated RNA interference technology and to investigate the hepatotoxicity of trichloroethylene (TCE) in CYP2E1-silenced hepatocytes.</p><p><b>METHODS</b>Short hairpin RNA fragments were designed and synthesized and were then ligated into the lentiviral vector; single colonies were screened; the plasmid was extracted after PCR and sequence identification and then transferred into L02 hepatocytes; the CYP2E1-silenced hepatocytes were selected; real-time quantitative PCR and Western blot were used to evaluate the interference effects. The obtained CYP2E1-silenced hepatocytes, as well as normal L02 hepatocytes, were treated with TCE (0, 0.25, 0.50, 1.00, 2.00, and 4.00 mmol/L). The cell viability and half maximal inhibitory concentration (IC50) of TCE were measured; the apoptotic rate of cells was measured by flow cytometry; the mRNA expression levels of apoptosis genes and oncogenes were measured by real-time quantitative PCR.</p><p><b>RESULTS</b>The IC50s of TCE for L02 hepatocytes and CYP2E1-silenced hepatocytes were 15.1 mmol/L and 23.6 mmol/L, respectively. The apoptotic rate increased as the dose of TCE rose in the two types of cells; the CYP2E1-silenced hepatocytes hada significantly lower apoptotic rate than L02 hepatocytes when they were exposed to 2.0 and 4.0 mmol/L TCE (P < 0.05 or P < 0.01). The mRNA expression level of bcl-2 (anti-apoptosis gene) in CYP2E1-silenced hepatocytes was 15% ∼ 60% higher than that in L02 hepatocytes (P < 0.01), while the mRNA expression levels of caspase-3 and caspase-9 (apoptosis genes) in CYP2E1-silenced hepatocytes were 30% ∼ 60% lower than those in L02 hepatocytes (P < 0.01). The mRNA expression level of p53 (cancer suppressor gene) in CYP2E1-silenced hepatocytes was 81 - 278% higher than that in L02 hepatocytes (P < 0.01), while the mRNA expression levels of c-fos and k-ras (oncogenes) in CYP2E1-silenced hepatocytes were 20-68% lower than those in L02 hepatocytes (P < 0.01).</p><p><b>CONCLUSION</b>CYP2E1-silenced cells can be successfully prepared by lentivirus-mediated RNA interference technology. Silencing CYP2E1 gene can reduce the hepatotoxicity of TCE and inhibit the expression of some apoptosis genes and oncogenes, suggesting that CYP2E1 gene plays an important role in TCE metabolism and is related to the hepatotoxicity of TCE.</p>

Effects of bisphenol A on OCT4 and SOX2 genes expression in mouse embryonic stem cells / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effects of bisphenol A (BPA) exposure on toxicity characteristic and OCT4 and SOX2 gene expression of mouse embryonic stem cells (mESC).</p><p><b>METHODS</b>mESC were cultured, and treated with the doses of 10(-8), 10(-7), 10(-6), 10(-5), 10(-4) mol/L respectively of BPA and DMSO (the solvent control group)for 24 hours, and three groups of cells were treated with the same method. The morphological changes of mESC in the control and exposure groups were observed through an inverted microscope. Cell counting kit 8 (CCK8) was used to detect the effects of BPA on proliferation of mESC, and based on the results, the half inhibitory concentration (IC50) was calculated. Real-time fluorescent quantitative polymerase chain reaction (RT-QPCR) and western blotting were used to detect the expression of OCT4 and SOX2.</p><p><b>RESULTS</b>BPA had certain toxicity on mESC, the treatment of BPA significantly increased cell toxicity in a concentration-dependent manner, and the IC50 was 4.3×10(-4) mol/L, combined with the BPA exposure concentration of the environment and the related literature, eventually taking the five concentrations of 10(-8), 10(-7), 10(-6), 10(-5), 10(-4) mol/L as the experimental groups. The mESC morphology were effected after the treatment of BPA for 24 h, compared with the control group, the number of cells decreased, appearing some floating cells, and the cell cloning became irregular and differentiation in the higher concentration groups. The OCT4 mRNA expression level in the 10(-7) mol/L (1.146 ± 0.087), 10(-6) mol/L (1.156 ± 0.030), 10(-5) mol/L (1.158 ± 0.103) and the 10(-4) mol/L (1.374 ± 0.053) dose group were all significantly higher than the control group (1.000 ± 0.000) (t values were -2.384, -2.953, -3.203, -4.021 respectively, P value all < 0.05). Meanwhile, the SOX2 mRNA expression level in the 10(-4) mol/L (1.113 ± 0.052) were higher than the control group (1.000 ± 0.000) (t value was -2.765, P value < 0.05). Moreover, the OCT4 protein expression level in the 10(-5) mol/L (1.360 ± 0.168) and 10(-4) mol/L (1.602 ± 0.151) were all significantly higher than the control group (1.000 ± 0.000) (t values were -3.538, -4.002 respectively, P value all < 0.05), while no obvious change of the SOX2 protein expression level was detected in all treated groups.</p><p><b>CONCLUSION</b>BPA in a certain dose range could upregulate the expression of OCT4 gene in mouse embryonic stem cells while had no significant effect on the expression of SOX2 gene.</p>

Study on sperm damage caused by trichloroethylene in male rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study in vitro sperm damage caused by trichloroethylene in male rats.</p><p><b>METHODS</b>Sperms of Sprague-Dawley (SD) rats were collected 4 hours after being contaminated by trichloroethylene of 0, 2, 4, 6, 8, and 10 mmol/L in vitro. Giemsa staining was performed to observe the morphological changes of sperms, and flow cytometer was used to detect the changes in mitochondrial membrane potential.</p><p><b>RESULTS</b>The sperm motilities in 6, 8, and 10 mmol/L trichloroethylene groups decreased significantly compared with that in control group (P <0.01); the sperm aberration rates in 8 and 10 mmol/L trichloroethylene groups were significantly higher than that in control group (P<0.01). With the increase in exposure dose, the proportion of sperms with reduced mitochondrial membrane potential increased, and there were significant differences in sperm apoptosis rate between the 4, 6, 8, and 10 mmol/L trichloroethylene groups and control group (P<0.01).</p><p><b>CONCLUSION</b>In vitro exposure to trichloroethylene can reduce sperm motility and increase the aberration rate and apoptosis rate of sperms in male SD rats.</p>

Role of poly (ADP-ribose) polymerase 1 on DNA methylation variation induced by B(a)P in human bronchial epithelial cell / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate DNA methylation variation in human cells induces by B(a)P, and to explore the role of PARP1 during this process.</p><p><b>METHODS</b>The changes of DNA methylation of 16HBE and its PARP1-deficient cells exposed to B(a)P (1.0, 2.0, 5.0, 10.0, 15.0, 30.0 µmol/L) were investigated by immunofluorescence and high performance capillary electrophoresis, and simultaneously, the expression level of PARP 1 and DNMT 1 were monitored dynamically.</p><p><b>RESULTS</b>The percentage of methylated DNA of overall genome (mCpG%) in 16HBE and 16HBE-shPARP1 cells were separately (4.04 ± 0.08)% and (9.69 ± 0.50)%. After being treated by 5-DAC for 72 hours, mCpG% decreased to (3.15 ± 0.14)% and (6.07 ± 0.54)%. After both being exposed to B(a)P for 72 hours, the mCpG% in 16HBE group (ascending rank) were separately (5.10 ± 0.13), (4.25 ± 0.10), (3.91 ± 0.10), (4.23 ± 0.27), (3.70 ± 0.15), (3.08 ± 0.07); while the figures in 16HBE-shPARP1 group (ascending rank) were respectively (10.63 ± 0.60), (13.08 ± 0.68), (9.75 ± 0.55), (7.32 ± 0.67), (6.90 ± 0.49) and (6.27 ± 0.21). The difference of the results was statistically significant (F values were 61.67 and 60.91, P < 0.01). For 16HBE group, expression of PARP 1 and DNMT 1 were 141.0%, 158.0%, 167.0%, 239.0%, 149.0%, 82.9% and 108.0%, 117.0%, 125.0%, 162.0%, 275.0%, 233.0% comparing with the control group, whose difference also has statistical significance (t values were 11.45, 17.32, 32.24, 33.44, 20.21 and 9.87, P < 0.01). For 16HBE-shPARP1 group, expression of PARP 1 and DNMT 1 were 169.0%, 217.0%, 259.0%, 323.0%, 321.0%, 256.0% and 86.0%, 135.0%, 151.0%, 180.0%, 229.0%, 186.0% comparing with the control group, with statistical significance (t values were 9.06, 15.92, 22.68, 26.23, 37.19 and 21.15, P < 0.01). When the dose of B(a)P reached 5.0 µmol/L, the mRNA expression of DNMT 1 in 16HBE group (ascending rank) were 125.0%, 162.0%, 275.0%, 233.0% times of it in control group, with statistical significance (t values were 12.74, 24.92, 55.11, 59.07, P < 0.01); while the dose of B(a)P reached 2.0 µmol/L, the mRNA expression of DNMT 1 in 16HBE-shPARP1 group were 135.0%, 151.0%, 180.0%, 229.0%, 186.0% of the results in control group, and the differences were statistically significant (t values were 23.82, 40.17, 32.69, 74.85, 46.76, P < 0.01).</p><p><b>CONCLUSION</b>The hypomethylation of 16HBE cells induced by B(a)P might be one important molecular phenomenon in its malignant transformation process. It suggests that PARP1 could regulate DNA methylation by inhibiting the enzyme activity of DNMT1, and this effect could be alleviated by PARP1-deficiency.</p>

Effects of amitrole on thyroid hormone-associated gene transcription in FRTL-5 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effects of amitrole on the transcription of thyroglobulin (tg), thyroid peroxidase (tpo), Na(+)/I- symporter (nis), Na(+)/I- symporter (nis), thyroid-stimulating hormone receptor (tshr), thyroid transcription factor 1 (ttf-1) and paired-domain protein-8 (pax-8) genes in FRTL-5 cells and investigate the mechanism of amitrole for intervening in thyroid hormone activity.</p><p><b>METHODS</b>FRTL-5 cells were treated with amitrole at 0.001, 0.01 and 0.1 mg/ml for 24 h, respectively, after which the cells were collected for extraction of the total RNA. RT-PCR was used to examine the effects of amitrole on the transcription of tg, tpo, nis, tshr, pax-8 and ttf-1 genes in FRTL-5 cells.</p><p><b>RESULTS</b>Amitrole significantly induced tg gene transcription at all the doses, but produced no obvious effects on tpo and nis gene transcription. At the concentration of 0.1 mg/ml, amitrole significantly reduced pax-8 and tshr gene transcription but increased ttf-1 gene transcription.</p><p><b>CONCLUSION</b>The effects of amitrole on thyroid hormone activity may be related with its actions on tg, ttf-1, tshr and pax-8 gene transcription.</p>

Study on the relationship between organochlorine pesticides and level of residues in serum and daily foodstuff / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the contents of organochlorine pesticides in human bodies and residues in serum of populations with non-occupational exposure as well as to study the relationship between organochlorine pesticides in foodstuff and residues levels in serum.</p><p><b>METHODS</b>A cross-section study was conducted. 107 men and 142 women who were all healthy and living in the communities were investigated from Mar. 2004 to Jul. 2004. Level of daily food exposure was estimated through questionnaires while DDTs and HCHs serum levels were detected by EC-ECD. The relationship between organochlorine pesticides contents in foods and residues in serum were analyzed by ridge regression.</p><p><b>RESULTS</b>Fresh fish was positively correlated to men's serum level of beta-HCH and p,p'-DDT (beta = 0.1266 and beta = 0.0595) while vegetables and fruits were negatively correlated to women's serum level of beta-HCH (beta = -0.1066). Soybean was negatively correlated to women's serum level of p,p'-DDE and p,p'-DDT (beta = -0.0965 and 3 = -0.0581). Alcohol consumption was negatively correlated to men's serum level of beta-HCH and p,p'-DDE and women's serum level of p,p'-DDE (beta = -0.1315, beta = -0.1599 and P = -0.1128).Salted meat was negatively correlated to men's serum level of beta-HCH and p, p'-DDT (P = -0. 066 and P = - 0.0569).</p><p><b>CONCLUSION</b>In this study, fresh fish might increase the body burden of organochlorine pesticides and residues while alcohol might promote the excretion of organochlorine pesticides. Pickled meat and vegetal foodstuff might contain low-level of organochlorine pesticides and residues.</p>

Study on serum organochlorines pesticides (DDTs) level, CYP1A1 genetic polymorphism and risk of breast cancer: a case control study / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the potential effect of gene-environment interaction between CYP1A1 and serum dichlorodiphenyldichloroethane (DDT) levels on the risk of breast cancer in women, in China.</p><p><b>METHODS</b>A case-control study was conducted. From Dec. 2003 to Sep. 2004, 104 women with histologically confirmed breast cancers and 154 noncancerous controls from a community were enrolled in this study. Risk factors information of breast cancer was investigated by a questionnaire. Serum p, p'-dichlorodiphenyldichloroethane (p, p'-DDT) and 1, 1-dichloro-2, 2-bis (p-chlorophenyl) ethylene (p, p'-DDE) levels were tested by GC-ECD. CYP1A1 m2 gene type was tested by allele special-PCR method.</p><p><b>RESULTS</b>Serum DDT levels of case and control were (36.90 +/- 79.41) ng/ml and (50.60 +/- 150.70) ng/ml respectively. Serum 1, 1-dichloro-2, 2-bis (p-chlorophenyl) ethylene (p, p'-DDE) levels of case and control were (7.43 +/- 11.10) ng/ml and (8.96 +/- 11.30) ng/ml respectively. No statistically significant differences were found between the two groups with geometric mean t-test (P > 0.05). Compared with women who had homozygous wild-type CYP1A1 m2 genotype, significantly increased risks of breast cancer were found for women with the CYP1A1 m2 homozygous variant genotype [odds ratio (OR) = 2.61, 95% confidence interval (CI): 1.00 - 6.80]. Among premenopausal women, compared with women with homozygous wild-type of CYP1A1 genotype (Ile/Ile) and low serum DDT level (DDT serum level < or = 42.93 ng/ml), women with at least one variant allele of CYP1A1 m2 genotype and high serum DDT level (DDT serum level > or = 42.93 ng/ml) had higher risk of breast cancer (OR = 4.35, 95% CI: 1.140 - 16.950).</p><p><b>CONCLUSIONS</b>CYP1A1 m2 genetic polymorphism was associated with increased risk of female breast cancer while DDT exposure might have increased the risk of breast cancer among premenopausal women with CYP1A1 m2 variant genotype.</p>

Polymorphism of alcohol metabolizing-related enzyme genes and its correlation with drinking-behaviors in 201 cases of Chinese Han healthy population / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the distribution of genotypes about alcohol dehydrogenase 2 (ADH2) and aldehyde dehydrogenase 2 (ALDH2) and its relationship with drinking-behaviors in Chinese Han healthy population as to providing a theoretic direction for filtering out high-risk and sensitive individuals and taking preventive measures to decrease the alcohol-related diseases.</p><p><b>METHODS</b>Using questionnaires to select subjects (201 persons, including men 104, women 97) for collecting blood samples and data about drinking-behaviors. Techniques of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) were used to detect the genotypes of ADH2 and ALDH2.</p><p><b>RESULTS</b>Heterozygous ADH2 and homozygous ALDH2 were the two dominant ones (respectively 53.23%, 68.16%). There were no statistical differences among the distributions of nine combinations of ADH2 genotypes and ALDH2 ones. The difference of distribution of homozygous ALDH2 between males having high and middle drinking-frequencies seemed to be statistically meaningful.</p><p><b>CONCLUSION</b>The proportion of individuals carrying about "susceptible genotypes of alcohol-related diseases" in Chinese Han healthy population should be more than one half (68.16%), which calls on reinforcing the surveillance and preventing the alcohol-related diseases. Correlation between genotypes of ADH2 and ALDH2 and alcohol-related diseases should be more important.</p>

Potential antiviral drug Pueraria crude extract and puerarin protect against ethanol-induced cytotoxicity in embryonic mouse hippocampal cultures / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To examine whether Chinese medical herb Pueraria crude extract (CP) and standard of pure puerarin (SP) possess the same neuroprotective effects during concomitant ethanol (EtOH) treatment.</p><p><b>METHODS</b>Hippocampus cultures were prepared from mice at gestational age of 18 day. Cell viability was measured by MTT assay. RT-PCR was employed to determine mRNA expression of superoxide dismutase (SOD).</p><p><b>RESULTS</b>As measured by MTT assay, supplementation with 15 mg/L CP or 10 mg/L SP afforded neuroprotection against all EtOH concentrations (50, 200 and 350 mmol/L, respectively) in embryonic hippocampal culture system. In addition, both 15 mg/L CP and 10 mg/L SP could decrease expression of SOD at mRNA level.</p><p><b>CONCLUSION</b>This study suggests that CP and SP could decrease oxidative stress induced by ethanol treatment by the decreased expression of SOD at mRNA level, and demonstrates antioxidative neuroprotective effect of CP and SP against developmental ethanol exposure in vitro.</p>

Effects of zearalenone on proliferation and apoptosis in MCF-7 cells / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effects of zearalenone (ZEA) on proliferation and apoptosis in estrogen-dependent human breast cancer MCF-7 cells and the likely underlying molecular mechanisms.</p><p><b>METHODS</b>Cell viability was determined by MTT assay and cell cycle distribution by cytometry. Apoptosis was detected by Cell Death Detection ELISA and cytometry, respectively. The expressions of bax and bcl-2 were examined using multiple RT-PCR and Western-blot both at mRNA and protein level, respectively.</p><p><b>RESULTS</b>The current study confirmed the previous studies that ZEA could stimulate proliferation in MCF-7 cells with inducing a profound increase in S phase and a modest increase in G(2)/M phase that was accompanied by a decrease in G(0)/G(1) phase. ZEA could inhibit apoptosis in MCF-7 cells following estrogen ablation at a range of concentrations of 2 nmol/L -96 nmol/L. Western blot and RT-PCR analysis revealed that the anti-apoptotic bcl-2 was upregulated at both protein and mRNA level, together with the downregulation of pro-apoptotic bax.</p><p><b>CONCLUSION</b>ZEA should have possessed comparative estrogenic activity and could promote the progression of MCF-7 cells through the cell cycle by a decreasing in the G(0)/G(1) phase and by a significant increasing in S-phase. The pro-proliferative activity of ZEA was due to inhibition of apoptosis through regulation of bax/bcl-2 expression.</p>

Experimental studies on male reproductive toxicity of bisphenol A in vitro and vivo / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effects of Bisphenol A in adult rats and its possible mechanisms.</p><p><b>METHODS</b>BPA (in corn oil) was administered orally to 9-week-old male Sprague-Dawley rats for 14 days (0, 1 and 5 g/kg bw), and incubated primary Sertoli cells from pubertal SD rats with 0, 10(-7), 10(-6), 10(-5), 10(-4) mol/L BPA.</p><p><b>RESULTS</b>After oral administration, a significant decrease in right testis weight was observed in 5 g/kg dose group, but not in the 1 g/kg bw dose group. Germ cells were detached from basement membrane of seminiferous tubules and Sertoli cells in BPA-treated groups. Administration of BPA at 1 g/kg bw and 5 g/kg bw produced both nucleus pycnosis and vacuolized nucleus in germ cells and Sertoli cells. A marked loss in vimentin staining in Sertoli cells from testis of BPA-treated rats was detected. No change in levels of serum estradiol and testosterone was observed after two-week exposure to BPA. In Sertoli cell primary culture, BPA destroyed the cytoskeleton and cell-cell junctions, and elongated Sertoli cells.</p><p><b>CONCLUSION</b>These results suggest that BPA may injure reproductive function of male rats by destroying the cytoskeleton and changing the form of Sertoli cells.</p>

The effects of three plastic additives on the proliferation of MCF-7 cell / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effect of environmental estrogens on the proliferation of breast cancer cell line MCF-7.</p><p><b>METHODS</b>The tested compounds were n-4-nonyphenol, Bisphenol A and dibutylphthalate. Human estradiol-dependent MCF-7 breast cancer cells were grown in DMEM medium containing 10% bovine serum. Five days before the addition of the test compounds, the cells were washed by phosphate-buffered saline, and the medium was substituted with a phenol red-free DMEM medium containing 5% dextral charcoal-stripped FBS. The respective test compound was added in fresh medium and the control cell received only the vehicle (ethanol). The proliferation of MCF-7 was analyzed by the MTT assay, (3)H-TdR incorporation assay and flow cytometry.</p><p><b>RESULTS</b>Compared with the ethanol control, the proliferation and DNA synthesis of the test cells treated with n-4-nonyphenol (8 x 10(-7) mol/L, 96 h), Bisphenol A (8 x 10(-7) mol/L, 96 h) or dibutylphthalate (32 x 10(-6) mol/L, 96 h) treatment was markedly enhanced in a time-dependent and dose-dependent manner.</p><p><b>CONCLUSION</b>n-4-Nonyphenol, Bisphenol A and dibutylphthalate enhanced the proliferation of human breast cancer cell in vitro, which may demonstrate an estrogenic activity.</p>

Effects of genistein and zearalenone on proliferation of PEO4 / 中华预防医学杂志

<p><b>OBJECTIVE</b>The objective of this study was to investigate the estrogenic activity of genistein and zearalenone through their effects on the proliferative capacity of human ovarian PEO4.</p><p><b>METHODS</b>Estrogen receptor-positive PEO4 cell was grown in DMEM medium containing 10% bovine serum. Five days before the addition of the test compounds, the cells were washed in phosphate-buffered saline, and the medium was substituted with a phenol red-free DMEM medium containing 5% dextran charcoal-stripped FBS. The respective test compound was added in fresh medium and the control cell received only the vehicle (ethanol). Cell proliferation was detected respectively by MTT assay, (3)H-TdR incorporation and flow cytometry.</p><p><b>RESULTS</b>Compared with vehicle control, 96 x 10(-6) mol/L GS significantly inhibited PEO4 cell proliferation and DNA synthesis as measured by MTT and (3)H-TdR incorporation after treatment for 24 h. Alao, 32 x 10(-6) mol/L GS could exert inhibition on PEO4 cell growth as time extension to 48 h. 32 x 10(-6) mol/L approximately 96 x 10(-6) mol/L GS induced G(2)/M arrest. At low dose (< 8 x 10(-6) mol/L=, GS promoted proliferation in PEO4 cells. ZEA enhanced proliferation, promoted DNA synthesis and increased the S phase population in PEO4 cells.</p><p><b>CONCLUSIONS</b>Genistein possess estrogenic activity and zearalenone have anti-estrogenic activity. They play different effects on the proliferation of human ovarian cancer cell. Genistein enhanced the proliferation of PEO4. Zearalenone inhibited its the proliferation. These results implied that genistein and zearalenone elicit different signal-transduction channel.</p>

Effects of environmental estrogens on apoptosis induced by estrogen depletion in T47D cells / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effects of environmental estrogens (n-4-noniphenol, NP; bisphenol, BisA; and dibutylphthalate, DBP) on apoptosis induced by estrogen depletion in breast cancer T47D cells.</p><p><b>METHODS</b>Human T47D breast cancer cells were grown in DMEM medium containing 10% bovine serum. Four days before adding the test compounds, the cells were washed in phosphate-buffered saline, and the medium was substituted with a phenol red-free DMEM medium containing 5% dextral charcoal-stripped FBS. Respective test compound was added in fresh medium and the control cell received only the vehicle (ethanol). Apoptotic features in T47D cell were analyzed by light microscope that was commonly used to define apoptosis. DNA integrity of T47D cells was examined by agarose gel electrophoresis. Hypodiploid population was detected by flow cytometry.</p><p><b>RESULTS</b>The typical characters of apoptosis in T47D cells were observed after estrogen deletion and then disappeared following exposure to T47D cells at 32 x 10(-7) mol/L Np and 32 x 10(-7) mol/L BisA respectively. Inhibition of apoptosis at 32 x 10(-6) mol/L DBP was not shown in our study.</p><p><b>CONCLUSION</b>N-4-noniphenol and Bisphenol A could inhibit apoptosis induced by estrogen deletion in breast cancer T47D cells. This result suggests that these environmental estrogens might involve in signal transduction connected with apoptosis.</p>

Study on Effects of Estrogic Bisphenol_A on Vimentin in Sertoli Cells of Rats in Vitro / 环境与健康杂志

Objective To explore the mechanism of effect of estrogic bisphenol_A(BPA) on vimentin in Sertoli cells.Methods Immunohistochemical methods and situ hybridization technique were applied to analyze the effets of BPA on expressions of vimentin and protein kinase C(PKC) gene in primary cultured Sertoli cells.Results The results showed that BPA lengthened the Sertoli cells,the vimentin gene in Sertoli cells could be expressed completely in vitro,but BPA could prohibited translation of vimentin gene,however there was no direct relationship between BPA and vimentin protein degradation.PKC gene couldn't be expressed in Sertoli cells. Conclusion The results suggested that BPA prohibited translation of vimentin gene and therefore blocked the formation of cytoskeleton of Sertoli cells,and finally caused deformation of these cells,and that protein kinase C didn't disturb degradative metabolism of vimentin in Sertoli cells.