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Sample records for 17beta-estradiol e2 plasmatic

  1. Removal of 17beta-estradiol (E2) and its chlorination by-products from water and wastewater using non-imprinted polymer (NIP) particles.

    PubMed

    Murray, Audrey; Ormeci, Banu; Lai, E P C

    2011-01-01

    Endocrine disrupting compounds and their chlorination by-products are two classes of emerging contaminants. Surface water and wastewater treatment technologies have limitations in removing these contaminants. This study evaluated the ability of non-imprinted polymer particles (NIP) to remove the endocrine disruptor 17beta-estradiol (E2) and its chlorination by-products from water and wastewater. NIP effectively removed 98% of 10 mg/L E2 from wastewater. NIP were also effective in removing chlorination by-products of E2 by 84.9% after 10 mg/L E2 in water was chlorinated at 5 mg/L. In the presence of 5 mg/L humic acid, NIP were able to achieve removal of 10 mg/L E2 by greater than 99.9%. Furthermore, after chlorination of 10 mg/L E2 and 5 mg/L humic acid at 10 mg/L chlorine, NIP were also able to remove the chlorination by-products formed as well as the remaining E2 by greater than 99.9%. The presence of 5 mg/L humic acid did not adversely affect the adsorption efficiency. The results of this research indicate that NIPs have good potential as a final treatment step for surface water and wastewater treatment.

  2. delta 9-THC and 17-beta-estradiol in hippocampus.

    PubMed

    Foy, M R; Teyler, T J; Vardaris, R M

    1982-04-01

    Electrophysiological field potentials recorded from in vitro hippocampal slice preparations show dose-dependent differences in response to 17-beta-estradiol (E2) and delta-9-tetrahydrocannabinol (THC) added to the incubation medium. Using a wide range of doses (1 pM-10 nM), it was found that mid-range concentrations of estradiol (100 pM) and THC (10 pM) tended to increase field potentials in CA1 of rodents. Higher dose levels of each agent were found to depress neuronal activity. In the context of prior findings, these results suggest that the two compounds share a common mechanism of action in the hippocampus.

  3. [Photodegradation of 17beta-estradiol induced by Chlorella vulgaris].

    PubMed

    Ge, Liyun; Deng, Huanhuan; Wu, Feng; Weng, Yue; Deng, Nansheng

    2004-07-01

    The study showed that when exposed to high-pressure Hg-lamp (HPML, lambda(max) > or = 365 nm), and the concentration of Chlorella vulgaris was 4.0 x 10(10) cells x L(-1), the photodegradation rate of 17beta-estradiol could reach to 37%. When the concentration of Chlorella vulgaris was 4.2 x 10(10) cells x L(-1), the photodegradation of 1.5 x 10(-5) - 6.0 x 10(-5) mol x L(-1) 17beta-estradiol in aqueous solutions was pseudo-first order reaction. Increasing the initial concentration of 17beta-estradiol could lower its photodegradation rate. The influence of light intension and Chlorella vulgaris concentration on the photodegradation of 17beta-estradiol was also studied in this paper.

  4. Effects of 17beta-estradiol on mussel digestive gland.

    PubMed

    Canesi, Laura; Borghi, Cristina; Fabbri, Rita; Ciacci, Caterina; Lorusso, Lucia Cecilia; Gallo, Gabriella; Vergani, Laura

    2007-01-01

    In bivalve molluscs the digestive gland (hepatopancreas) plays a central role in metabolism. In this work, the effects of 17beta-estradiol (E(2)) on digestive gland were evaluated in Mytilus galloprovincialis. Mussels were injected into the adductor muscle sinus with different amounts of the hormone (5, 25 and 100pmol) and tissues were sampled 24h post-injection. Functional parameters (lysosomal membrane stability-LMS, lysosomal accumulation of neutral lipids-NL and of lipofuscin-LF), as well as the activity of the key glycolytic enzymes PFK (phosphofructokinase) and PK (pyruvate kinase), and of the antioxidant enzyme catalase were evaluated. Selected genes, whose expression can be modulated by estrogens in mammalian systems and whose sequences have been identified in Mytilus, were investigated as possible targets for the action of E(2). E(2) induced a concentration-dependent decrease in LMS; such an effect was accompanied by an increase in NL accumulation, whereas the level of lipofuscin showed a slight, although not significant decrease. E(2) exposure also led to a significant increase in the activity of PFK and catalase but not of PK. Moreover, E(2) induced significant changes in the pattern of gene expression at the lower concentrations tested (5 and 25pmol) as evaluated by quantitative RT-PCR. In particular, increased transcription of catalase, as well as of the metallothionein 20 (MT20) isoform were observed; on the other hand, a decreased transcription of the p53 gene was detected. The results demonstrate that in Mytilus the digestive gland represents a target for the action of E(2), and that the hormone can modulate the lysosomal function, as well as lipid and glucose metabolism. Moreover, these data suggest that E(2) may also alter oxidative stress conditions in this tissue, as indicated by the increased transcription of genes (metallothionein and catalase) that play a role in antioxidant defences. Overall, the results indicate that E(2) can modulate both

  5. High-performance liquid chromatographic determination of 17beta-estradiol and 17beta-estradiol-3-acetate solubilities and diffusion coefficents in silicone elastromeric intravaginal rings.

    PubMed

    Russell, J A; Malcolm, R K; Campbell, K; Woolfson, A D

    2000-07-07

    A rapid, sensitive reversed-phase high-performance liquid chromatographic method has been developed for the determination of in vitro release of 17beta-estradiol and its ester prodrug, 17beta-estradiol-3-acetate, from silicone intravaginal rings. Partial hydrolysis of the acetate under the aqueous conditions provided by the 1% benzalkonium chloride release medium necessitates its conversion to 17beta-estradiol prior to HPLC analysis. Both steroid peaks have been fully resolved from the benzalkonium chloride peaks by the reported chromatographic method, which employs a C18 bonded reversed-phase column, an acetonitrile-water (50:50, v/v) mobile phase and a UV detection wavelength of 281 nm. The peak area versus 17beta-estradiol concentration was found to be linear over the range of 0.0137-1347 microkg ml(-1). The HPLC method has also been used to determine the silicone solubilities and diffusion coefficients of the two related steroids. The almost 100-fold increase in 17beta-estradiol-3-acetate release from the silicone core-type intravaginal rings compared to 17beta-estradiol is shown to be due to a 60-fold increase in silicone solubility and a one and a half-fold increase in diffusitivity. The results demonstrate that an effective estrogen replacement therapy dose of 17beta-estradiol may be administered from a silicone intravaginal reservoir device containing the labile 17beta-estradiol-3-acetate prodrug.

  6. Fat-soluble 17 beta-estradiol: a way of reducing dosage in steroid hormonal substitution?

    PubMed

    Schubert, W; Cullberg, G

    1988-01-01

    Eight ovariectomized women were given 0.5 mg 17 beta-estradiol cyclo-octyl acetate (E2COA) dissolved in arachis oil + 0.15 mg desogestrel, and 2 mg micronized 17 beta-estradiol (mE2) + 0.15 mg desogestrel orally in a crossover fashion for 20 days each. The preparations were taken on 10 days together with a meal, on 10 days 3 hours after a meal. Blood samplings were performed 3 h after capsule ingestion for analysis of serum estradiol (S-E2), estrone (S-E1) and sex hormone binding globulin (SHBG). Before treatment, all women had climacteric complaints. During treatment these symptoms were alleviated and no discomfort was reported. No differences in serum levels of estrogens were found in either of the preparations when capsules were taken with or without food. However, serum levels of E2 were found to be 100% higher per mg substance given after E2COA vis-à-vis mE2. This indicates either a delayed breakdown and/or a better resorption. The E1/E2 ratio after E2COA was only half that after mE2 intake. This hints at another route of resorption. SHBG concentrations were somewhat elevated following mE2 administration, whereas a slight decrease was found after E2COA. The resulting post-treatment difference was significant, suggesting a less estrogenic liver effect by E2COA. No accumulation of E2 or E1 was seen after either of the preparations. Our findings support the hypothesis that E2COA, being fat soluble, is resorbed via the lymphatic system. By avoiding the first liver pass the dosage of estrogen can be halved.

  7. 2-Hydroxy-4-glutathion-S-yl-17beta-estradiol and 2-hydroxy-1-glutathion-S-yl-17beta-estradiol produce oxidative stress and renal toxicity in an animal model of 17beta-estradiol-mediated nephrocarcinogenicity.

    PubMed

    Butterworth, M; Lau, S S; Monks, T J

    1998-01-01

    Chronic exposure of male Syrian hamsters to a variety of estrogens has been linked with a high incidence of renal carcinoma. The basis of this species and tissue specificity remains to be resolved. We have recently shown that (i) 17beta-estradiol is nephrotoxic in the hamster in a manner dependent upon the activity of gamma-glutamyl transpeptidase and (ii) 17beta-estradiol is metabolized to a variety of catechol estrogen glutathione conjugates (Butterworth et al., Carcinogenesis, 18, 561-567, 1997). We report that the catechol estrogen glutathione conjugates exhibit redox properties similar to those of the catechol estrogens, and maintain the ability to generate superoxide radicals. Administration of 2-hydroxy-4-glutathion-S-yl-17beta-estradiol or 2-hydroxy-1-glutathion-S-yl-17beta-estradiol (0.27-5.0 micromol/kg) to Syrian hamsters, produces mild nephrotoxicity. Repeated daily administration of 2-hydroxy-4-glutathion-S-yl-17beta-estradiol causes a sustained elevation in urinary markers of renal damage and in the concentration of renal protein carbonyls and lipid hydroperoxides. Catechol estrogen oxidation and conjugation of glutathione in the liver, followed by the selective uptake of the redox active conjugates in tissues rich in gamma-glutamyl transpeptidase may contribute to 17beta-estradiol-induced renal tumors in the hamster.

  8. Influence of agricultural antibiotics and 17beta-estradiol on the microbial community of soil.

    PubMed

    Chun, Soul; Lee, Jaehoon; Radosevich, Mark; White, David C; Geyer, Roland

    2006-01-01

    Agricultural pharmaceuticals are a major environmental concern because of their hazardous effects on human and wildlife. This study analyzed phospholipid ester-linked fatty acids (PLFAs) and quinones to investigate the effects of a steroid (17beta-estradiol) and agricultural antibiotics (chlortetracycline and tylosin) on soil microbes in the laboratory. Two different types of soil were used: Sequatchie loam (0.8% organic matter) and LaDelle silt loam (9.2% organic matter). The soils were spiked with 17beta-estradiol and antibiotics, alone or in combination. In Sequatchie loam, 17beta-estradiol significantly increased the microbial biomass, especially the biomarkers for beta proteobacteria (16:1omega7c, 18:1omega7c, Cy17:0, and UQ-8). The coexistence of antibiotics decreased the stimulatory effect of 17beta-estradiol on the microbial community. In LaDelle silt loam, there were no significant differences in total microbial biomass and their microbial community structure among the treatments. Overall, 17beta-estradiol changed the microbial community of soil and the presence of antibiotics nullified the effect of 17beta-estradiol. However, the effects of 17beta-estradiol and antibiotics on soil microbes were sensitive to the soil properties, as seen in the LaDelle silt loam.

  9. Low-dosage micronized 17 beta-estradiol prevents bone loss in postmenopausal women

    NASA Technical Reports Server (NTRS)

    Ettinger, B.; Genant, H. K.; Steiger, P.; Madvig, P.

    1992-01-01

    With the use of a double-blind, randomized, dose-ranging design, we tested during an 18-month period the degree of protection against postmenopausal bone loss afforded by micronized 17 beta-estradiol in dosages of 0.5, 1.0, and 2.0 mg. All subjects received supplementation to ensure a minimum of 1500 mg calcium daily. Fifty-one subjects completed at least 1 year of follow-up bone density measurements by quantitative computed tomography and by single- and dual-photon absorptiometry. In the placebo group spinal trabecular bone density decreased 4.9% annually (p less than 0.001), whereas in those taking micronized 17 beta-estradiol bone density tended to increase (annual increases of 0.3% in the 0.5 mg micronized 17 beta-estradiol group, 1.8% in the 1.0 mg micronized 17 beta-estradiol group, and 2.5% in the 2.0 mg micronized 17 beta-estradiol group). After completing the double-blind phase, 41 subjects completed an additional 18 months of follow-up while taking 1.0 mg micronized 17 beta-estradiol. During this time one third of the subjects were randomly assigned to discontinue calcium supplements. Among those who previously received placebo, trabecular bone density increased 4.3% annually, whereas among those who had used micronized 17 beta-estradiol, trabecular bone density response was inversely related to the dosage previously used. Additionally and independently, the level of calcium intake showed a statistically significant correlation with the change in spinal trabecular bone density (r = 0.37, p = 0.02). We conclude that micronized 17 beta-estradiol has a continuous skeletal dose-response effect in the range of 0.5 to 2.0 mg and that calcium intake positively modifies the skeletal response to 1.0 mg micronized 17 beta-estradiol.

  10. Low-dosage micronized 17 beta-estradiol prevents bone loss in postmenopausal women

    NASA Technical Reports Server (NTRS)

    Ettinger, B.; Genant, H. K.; Steiger, P.; Madvig, P.

    1992-01-01

    With the use of a double-blind, randomized, dose-ranging design, we tested during an 18-month period the degree of protection against postmenopausal bone loss afforded by micronized 17 beta-estradiol in dosages of 0.5, 1.0, and 2.0 mg. All subjects received supplementation to ensure a minimum of 1500 mg calcium daily. Fifty-one subjects completed at least 1 year of follow-up bone density measurements by quantitative computed tomography and by single- and dual-photon absorptiometry. In the placebo group spinal trabecular bone density decreased 4.9% annually (p less than 0.001), whereas in those taking micronized 17 beta-estradiol bone density tended to increase (annual increases of 0.3% in the 0.5 mg micronized 17 beta-estradiol group, 1.8% in the 1.0 mg micronized 17 beta-estradiol group, and 2.5% in the 2.0 mg micronized 17 beta-estradiol group). After completing the double-blind phase, 41 subjects completed an additional 18 months of follow-up while taking 1.0 mg micronized 17 beta-estradiol. During this time one third of the subjects were randomly assigned to discontinue calcium supplements. Among those who previously received placebo, trabecular bone density increased 4.3% annually, whereas among those who had used micronized 17 beta-estradiol, trabecular bone density response was inversely related to the dosage previously used. Additionally and independently, the level of calcium intake showed a statistically significant correlation with the change in spinal trabecular bone density (r = 0.37, p = 0.02). We conclude that micronized 17 beta-estradiol has a continuous skeletal dose-response effect in the range of 0.5 to 2.0 mg and that calcium intake positively modifies the skeletal response to 1.0 mg micronized 17 beta-estradiol.

  11. Estrone and 17beta-estradiol concentrations in pasteurized-homogenized milk and commercial dairy products.

    PubMed

    Pape-Zambito, D A; Roberts, R F; Kensinger, R S

    2010-06-01

    Some individuals fear that estrogens in dairy products may stimulate growth of estrogen-sensitive cancers in humans. The presence of estrone (E(1)) and 17beta-estradiol (E(2)) in raw whole cow's milk has been demonstrated. The objectives of this study were to determine if pasteurization-homogenization affects E(2) concentration in milk and to quantify E(1) and E(2) concentrations in commercially available dairy products. The effects of pasteurization-homogenization were tested by collecting fresh raw milk, followed by pasteurization and homogenization at 1 of 2 homogenization pressures. All treated milks were tested for milk fat globule size, percentages of milk fat and solids, and E(2) concentrations. Estrone and E(2) were quantified from organic or conventional skim, 1%, 2%, and whole milks, as well as half-and-half, cream, and butter samples. Estrone and E(2) were quantified by RIA after organic solvent extractions and chromatography. Pasteurization-homogenization reduced fat globule size, but did not significantly affect E(2), milk fat, or milk solids concentrations. Estrone concentrations averaged 2.9, 4.2, 5.7, 7.9, 20.4, 54.1 pg/mL, and 118.9 pg/g in skim, 1%, 2%, and whole milks, half-and-half, cream, and butter samples, respectively. 17Beta-estradiol concentrations averaged 0.4, 0.6, 0.9, 1.1, 1.9, 6.0 pg/mL, and 15.8 pg/g in skim, 1%, 2%, whole milks, half-and-half, cream, and butter samples, respectively. The amount of fat in milk significantly affected E(1) and E(2) concentrations in milk. Organic and conventional dairy products did not have substantially different concentrations of E(1) and E(2). Compared with information cited in the literature, concentrations of E(1) and E(2) in bovine milk are small relative to endogenous production rates of E(1) and E(2) in humans.

  12. Estrogenic potencies of resorcylic acid lactones and 17 beta-estradiol in female rats.

    PubMed

    Everett, D J; Perry, C J; Scott, K A; Martin, B W; Terry, M K

    1987-01-01

    Uterotrophic response in sexually immature female rats has been used to rank the relative estrogenic potencies of six resorcylic acid lactones (RALs) and to compare their activities with that of 17 beta-estradiol. On oral administration, the estrogenic potency relative to 17 beta-estradiol is as follows: 7 alpha-zearalenol, 10 times less; zeranol, 150 times less; taleranol, 350 times less; zearalanone, 400 times less; zearalenone, 650 times less; 7 beta-zearalenol, 3500 times less. On subcutaneous administration, zeranol is 500 times less estrogenic than 17 beta-estradiol.

  13. Influence factor of 17beta-estradiol photodegradation by heterogeneous Fenton reaction.

    PubMed

    Zhao, Yaping; Huang, Minsheng; Ge, Ming; Tang, Xiaochun; Liu, Lu

    2010-01-01

    The photocatalytic degradation of 17beta-estradiol (E2), by Fenton like reaction was investigated as a function of E2 concentrations, organic co-solvents and co-existing estrogens, humic acid (HA) and other background anions. E2 degradation was effectively achieved by hydroxyl radicals that were generated in the heterogeneous photo-Fenton process. The degradation kinetics were fitted to Langmuir-Hinshelwood model with kr = 0.3140 microM/h and Kads = 2.2146L/micromol. The removal kinetics of E2 were initiated by a rapid decay and then followed by a much slower one in acetonitrile-water solutions while in methanol-water solutions they followed the first-kinetic model for the diffusion-control of hydroxyl radicals and competition between E2 and co-solvents. In addition, the lower level of co-existing substances did not significantly influence the oxidation efficiency of E2. The degradation rates of E2 were found to depend not only on the concentrations of hydrogen peroxide and iron content as reported before but also on pH, E2 concentrations and composition of co-solvents. Thus it is very important to look for the optimum conditions for the purpose of most efficiently eliminating E2 from drinking water.

  14. Abiotic oxidation of 17beta-estradiol by soil manganese oxides.

    PubMed

    Daniel Sheng, G; Xu, Chao; Xu, Lei; Qiu, Yuping; Zhou, Hongyi

    2009-10-01

    The degradation of 17beta-estradiol (E2) in sterile soil and Mn-free soil slurries was determined. In 0.075 g ml(-1) soil slurry, E2 with an initial concentration of 0.0267 micromol g(-1) was rapidly degraded and near equimolar estrone (E1) accumulated. A mass balance involving E2 and E1 existed throughout the reaction. The E2 degradation was thus an oxidation process and E1 was the only product. The concurrent release of Mn(II) during E2 oxidation and a lack of E2 oxidation in Mn-free soil slurry together demonstrated that soil manganese oxides were responsible for E2 oxidation. The degree of E2 oxidation was higher at high pH than at low pH, consistent with the fact that the reaction released protons. This study suggests that manganese oxides may be used as soil amendments to effectively oxidize E2 to less potent E1 in soil.

  15. Modulation of ovine SBD-1 expression by 17beta-estradiol in ovine oviduct epithelial cells

    PubMed Central

    2012-01-01

    Background Mucosal epithelia, including those of the oviduct, secrete antimicrobial innate immune molecules (AIIMS). These have bactericidal/bacteriostatic functions against a variety of pathogens. Among the AIIMs, sheep β-defensin-1 (SBD-1) is one of the most potent. Even though the SBD-1 is an important AIIM and it is regulated closely by estrogenic hormone, the regulation mechanism of 17β-estradiol has not been clearly established. We investigated the effects of E2 and agonist or inhibitor on ovine oviduct epithelial cells in regard to SBD-1 expression using reverse transcription quantitative PCR (RT-qPCR). In addition, three different pathways were inhibited separately or simultaneously to confirm the effect of different inhibitors in the regulation mechanism. Results 17beta-estradiol (E2) induced release of SBD-1 in ovine oviduct epithelial cells. SBD-1 expression was mediated through G-protein-coupled receptor 30 (GPR30) and Estrogen Receptors (ERs) activation in ovine oviduct epithelial cell. Inhibition of gene expression of protein kinase A (PKA), protein kinase C (PKC), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) led to a decreased SBD-1 expression. Conclusions Taken together, E2-induced up-regulation of SBD-1 expressions were GPR30-dependent during prophase and ERs-dependent during later-stage in ovine oviduct epithelial cells, and we assume that the effect was completed by the PKA, PKC, and NF-κB pathways simultaneous. PMID:22920556

  16. 17beta-Estradiol reverses shear-stress-mediated low density lipoprotein modifications.

    PubMed

    Hwang, Juliana; Rouhanizadeh, Mahsa; Hamilton, Ryan T; Lin, Tiantian C; Eiserich, Jason P; Hodis, Howard N; Hsiai, Tzung K

    2006-08-15

    Within arterial bifurcations or branching points, oscillatory shear stress (OSS) induces oxidative stress mainly via the reduced nicotinamide adenine dinucleodtide phosphate (NADPH) oxidase system. It is unknown whether 17beta-estradiol (E(2)) can regulate OSS-mediated low-density lipoprotein (LDL) modifications. Bovine aortic endothelial cells were pretreated with E(2) at 5 nmol/L, followed by exposure to OSS (0 +/- 3.0 dynes/cm(2) s and 60 cycles/min) in a flow system. E(2) decreased OSS-mediated NADPH oxidase mRNA expression, and E(2)-mediated (.-)NO production was mitigated by the NO synthase inhibitor N(G)-nitro-l-argenine methyl ester. The rates of O(2)(-.) production in response to OSS increased steadily as determined by superoxide-dismutase-inhibited ferricytochrome c reduction; whereas, pretreatment with E(2) decreased OSS-mediated O(2)(-.) production (n = 4, p < 0.05). In the presence of native LDL (50 microg/mL), E(2) also significantly reversed OSS-mediated LDL oxidation as determined by high-performance liquid chromatography. In the presence of O(2)(-.) donor, xanthine oxidase (XO), E(2) further reversed XO-induced LDL lipid peroxidation (n = 3, p < 0.001). Mass spectra acquired in the m/z 400-1800 range, revealed XO-mediated LDL protein nitration involving tyrosine 2535 in the alpha-2 domains, whereas pretreatment with E(2) reversed nitration, as supported by the changes in nitrotyrosine intensities. Thus, E(2) plays an indirect antioxidative role. In addition to upregulation of endothelial (.-)NO synthase and downregulation of Nox4 expression, E(2) influences LDL modifications via lipid peroxidation and protein nitration.

  17. Differential mass spectrometry of rat plasma reveals proteins that are responsive to 17beta-estradiol and a selective estrogen receptor modulator PPT.

    PubMed

    Zhao, Xuemei; Deyanova, Ekaterina G; Lubbers, Laura S; Zafian, Pete; Li, Jenny J; Liaw, Andy; Song, Qinghua; Du, Yi; Settlage, Robert E; Hickey, Gerry J; Yates, Nathan A; Hendrickson, Ronald C

    2008-10-01

    Estrogens are a class of steroid hormones that interact with two related but distinct nuclear receptors, estrogen receptor (ER) alpha and beta. To identify potential ER biomarkers, we profiled the rat plasma glycoproteome after treatment with vehicle or 17beta-estradiol (E2) or an ERalpha-selective agonist PPT by differential mass spectrometry. Our comparative proteomic experiment identifies novel E2- and PPT-responsive proteins, such as serine protease inhibitor family members.

  18. Effect of 17beta-estradiol on the immunocompetence of Japanese sea bass (Lateolabrax japonicus).

    PubMed

    Thilagam, Harikrishnan; Gopalakrishnan, Singaram; Bo, Jun; Wang, Ke-Jian

    2009-08-01

    Environmental contaminants can interfere with hormonal regulation in both vertebrates and invertebrates, and these contaminants may disrupt the endocrine system of human and other organisms. Evidence is growing that contaminants may be partly responsible for the observed increase of disease in marine organisms by adversely affecting their immunity. Fish are commonly used as sentinel organisms in vertebrate immunotoxicology; however, to date, studies have been undertaken only on a single size group of fish (juvenile/adult) and for acute exposure. In the present study, Lateolabrax japonicus fingerlings and juveniles were exposed to two sublethal concentrations (200 and 2,000 ng/L) of 17beta-estradiol (E2) for 30 d under laboratory conditions, and alterations in immune parameters comprising differential leukocyte count, respiratory burst, myeloperoxidase, immunoglobulin levels, serum lysozyme, and bactericidal activity were investigated to establish whether estrogen produced immunomodulation and to understand the effects of long-term exposure on these immune parameters in fish fingerlings and juveniles. The results revealed a significant elevation of respiratory burst activity, myeloperoxidase, immunoglobulin levels, and differential leukocyte counts of the fish exposed to estrogen compared to the control. The remaining parameters were significantly reduced in the experimental groups when compared to the control. The results indicated that sublethal E(2) exposure induced immunomodulation in both fingerling and juvenile L. japonicus, and the changes caused by estrogen might affect the function of immune system in fish.

  19. Naringenin and 17beta-estradiol coadministration prevents hormone-induced human cancer cell growth.

    PubMed

    Bulzomi, Pamela; Bolli, Alessandro; Galluzzo, Paola; Leone, Stefano; Acconcia, Filippo; Marino, Maria

    2010-01-01

    Flavonoids have been described as health-promoting, disease-preventing dietary components. In vivo and in vitro experiments also support a protective effect of flavonoids to reduce the incidence of certain hormone-responsive cancers. In particular, our previous results indicate that the flavanone naringenin (Nar), decoupling estrogen receptor alpha (ERalpha) action mechanisms, drives cancer cells to apoptosis. Because these studies were conducted in the absence of the endogenous hormone 17beta-estradiol (E2), the physiological relevance of these findings is not clear. We investigate whether the antiproliferative Nar effect persists in the presence of physiological E2 concentration (i.e. 10 nM), using both ERalpha-transfected (HeLa cells) and ERalpha-containing (HepG2 cells) cancer cell lines. Ligand saturation experiments indicate that Nar decreases the binding of E2 to ERalpha without impairing the estrogen response element (ERE)-driven reporter plasmid activity. In contrast, Nar stimulation prevents E2-induced extracellular regulated kinases (ERK1/2) and AKT activation and still induces the activation of p38, the proapoptotic member of mitogen-activating protein kinase (MAPK) family. As a consequence, Nar stimulation impedes the E2-induced transcription of cyclin D1 promoter and reverts the E2-induced cell proliferation, driving cancer cell to apoptosis. Thus, these results suggest that coexposure to this low-affinity, low-potency ligand for ERalpha specifically antagonizes the E2-induced ERalpha-dependent rapid signals by reducing the effect of the endogenous hormone in promoting cellular proliferation. As a whole, these data indicate that Nar is an excellent candidate as a chemopreventive agent in E2-dependent cancers.

  20. 17Beta-estradiol mediates the sex difference in capsaicin-induced nociception in rats.

    PubMed

    Lu, Yu-Ching; Chen, Chao-Wei; Wang, Su-Yi; Wu, Fong-Sen

    2009-12-01

    We have previously shown that the male sex steroid testosterone inhibits slightly, but the female sex steroid 17beta-estradiol (E(2)) potentiates dramatically, the capsaicin receptor-mediated current in rat dorsal root ganglion (DRG) neurons. Here, we used pharmacological methods and the nociceptive behavioral test to determine whether there is a sex difference in capsaicin-induced acute pain in rats in vivo and what mechanism underlies this sex difference. Results revealed that intradermal injection of capsaicin induced a dose-dependent nocifensive response in males and females, with the dose required to produce a comparable level of nociception being approximately 3- to 4-fold higher in males than in females. In addition, females during the proestrus stage exhibited significantly greater capsaicin-induced nocifensive responses compared with the estrus stage. Moreover, the female's enhanced sensitivity to the capsaicin-induced nocifensive response was completely reversed by ovariectomy 6 weeks before capsaicin injection. It is noteworthy that intradermal coinjection of E(2) but not progesterone with capsaicin potentiated the capsaicin-induced nocifensive response in ovariectomized rats. Likewise, intradermal E(2) injection dose-dependently potentiated the capsaicin-induced nocifensive response in male rats. Furthermore, potentiation by E(2) of the capsaicin-induced nocifensive response in male rats was not significantly reduced by a selective protein kinase C (PKC) inhibitor or by a selective protein kinase A (PKA) inhibitor, indicating that neither PKC nor PKA was involved in the effect of E(2). These data demonstrate that E(2) mediates the female's enhanced sensitivity to capsaicin-induced acute pain, consistent with potentiation by E(2) of the capsaicin receptor-mediated current in rat DRG neurons.

  1. Effects of 17 beta-estradiol exposure on Xenopus laevis gonadal histopathology.

    PubMed

    Wolf, Jeffrey C; Lutz, Ilka; Kloas, Werner; Springer, Timothy A; Holden, Larry R; Krueger, Henry O; Hosmer, Alan J

    2010-05-01

    The natural estrogen 17 beta-estradiol (E2) is a potential environmental contaminant commonly employed as a positive control substance in bioassays involving estrogenic effects. The aquatic anuran Xenopus laevis is a frequent subject of reproductive endocrine disruptor research; however, histopathological investigations have tended to be less than comprehensive. Consequently, a study was designed to characterize gross and microscopic changes in the gonads of X. laevis as a result of E2 exposure. Additional goals of this study, which consisted of three separate experiments, included the standardization of diagnostic terminology and criteria, the validation of statistical methodology, and the establishment of a half maximal effective concentration (EC50) for E2 as defined by an approximately 50% conversion of presumptive genotypic males to phenotypic females. In the first experiment, frogs were exposed to nominal concentrations of 0, 0.2, 1.5, or 6.0 microg/L E2. From these experimental results and those of a subsequent range finding trial, the EC50 for E2 was determined to be approximately 0.2 microg/L. This E2 concentration was utilized in the other two experiments, which were performed at different facilities to confirm the reproducibility of results. Experiments were conducted according to Good Laboratory Practice guidelines, and the histopathologic evaluations were peer reviewed by an independent pathologist. Among the three trials, the histopathological findings that were strongly associated with E2-exposure (p<0.001 to 0.0001) included an increase in the proportion of phenotypic females, mixed sex, dilated testis tubules, dividing gonocytes in the testis, and dilated ovarian cavities in phenotypic ovaries. A comparison of the gross and microscopic evaluations suggested that some morphologic changes in the gonads may potentially be missed if studies rely entirely on macroscopic assessment.

  2. Genistein potentiates the effect of 17-beta estradiol on human hepatocellular carcinoma cell line

    PubMed Central

    Kavoosi, Fraidoon; Dastjerdi, Mehdi Nikbakht; Valiani, Ali; Esfandiari, Ebrahim; Sanaei, Masumeh; Hakemi, Mazdak Ganjalikhani

    2016-01-01

    Background: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. This cancer may be due to a multistep process with an accumulation of epigenetic alterations in tumor suppressor genes (TSGs), leading to hypermethylation of the genes. Hypermethylation of TSGs is associated with silencing and inactivation of them. It is well-known that DNA hypomethylation is the initial epigenetic abnormality recognized in human tumors. Estrogen receptor alpha (ERα) is one of the TSGs which modulates gene transcription and its hypermethylation is because of overactivity of DNA methyltransferases. Fortunately, epigenetic changes especially hypermethylation can be reversed by pharmacological compounds such as genistein (GE) and 17-beta estradiol (E2) which involve in preventing the development of certain cancers by maintaining a protective DNA methylation. The aim of the present study was to analyze the effects of GE on ERα and DNMT1 genes expression and also apoptotic and antiproliferative effects of GE and E2 on HCC. Materials and Methods: Cells were treated with various concentrations of GE and E2 and the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay was used. Furthermore, cells were treated with single dose of GE and E2 (25 μM) and flow cytometry assay was performed. The expression level of the genes was determined by quantitative real-time reverse transcription polymerase chain reaction. Results: GE increased ERα and decreased DNMT1 genes expression, GE and E2 inhibited cell viability and induced apoptosis significantly. Conclusion: GE can epigenetically increase ERα expression by inhibition of DNMT1 expression which in turn increases apoptotic effect of E2. Furthermore, a combination of GE and E2 can induce apoptosis more significantly. PMID:27656602

  3. Antioxidant peroxiredoxin 3 expression is regulated by 17beta-estradiol in rat white adipose tissue.

    PubMed

    Bauzá-Thorbrügge, Marco; M Galmés-Pascual, Bel; Sbert-Roig, Miquel; J García-Palmer, Francisco; Gianotti, Magdalena; M Proenza, Ana; Lladó, Isabel

    2017-09-01

    Peroxiredoxin 3 (PRX3) plays a role as a regulator of the adipocyte mitochondrial function due to its antioxidant activity. We have previously reported the existence of a sexual dimorphism in the mitochondrial oxidative stress status of many rat tissues such as white (WAT) and brown (BAT) adipose tissues. The aim was to elucidate whether sex hormones may play a role in PRX3 expression in the adipose tissues of rats. In in vivo experiments, male and female standard diet fed rats, high fat diet (HFD) fed rats and rosiglitazone-supplemented HFD (HDF+Rsg) fed rats, as well as ovariectomized (OVX) and 17beta-estradiol-supplemented OVX (OVX+E2) female rats were used. 3T3-L1 adipocytes and brown adipocyte primary culture were used to study the roles of both E2 and testosterone in in vitro experiments. PRX3 levels were greater in the WAT of female rats than in males. This sexual dimorphism disappeared by HFD feeding but was magnified with Rsg supplementation. PRX3 sexual dimorphism was not observed in BAT, and neither HFD nor ovariectomy modified PRX3 levels. Rsg increased Prx3 expression in the BAT of both sexes. In vitro studies supported the results obtained in vivo and confirmed the contribution of E2 to sex differences in WAT Prx3 expression. Finally, we reported an E2 upregulation of both PRX3 and thioredoxin 2 (TRX2) in WAT but not in BAT that could play a key role in the sex dimorphism reported in the antioxidant defence of WAT in order to palliate the detrimental effect of the oxidative stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Toxicity of 17 {beta}-estradiol and dibutyl-n-phthalate to Japanese medaka (Oryzias latipes)

    SciTech Connect

    Patvna, P.J.; Cooper, K.R. |

    1995-12-31

    Phthalate esters are ubiquitous environmental contaminants that are hypothesized to cause developmental toxicity in aquatic organisms via an estrogenic mechanism. Japanese medaka embryos and larvae provide an excellent model for the study of toxicant effects on embryonic development. The following groups were examined (N = 10--20): a non-treatment control, a vehicle control, 17 {beta}-estradiol and Dibutyl-n-phthalate, in individual glass vials. The medaka embryos were treated beginning at the blastula stage, for ten days. At day 10, embryos were changed into fresh rearing solution. The embryos were observed daily, until three days post-hatching, for toxic developmental effects. Exposure to 17 {beta}-estradiol caused urinary bladder lesions at the lowest doses tested. At concentrations {le} 3 {micro}M/0.82 ppm, 17 {beta}-estradiol caused inhibition of swim bladder inflation, pericardial edema, and marked cachexia. Dibutyl-n-phthalate caused pronounced enlargement of the urinary bladder. No other gross lesions were observed. Both 17 {beta}-estradiol and Dibutyl-n-phthalate caused effects on the urinary tract which will be characterized at the light microscopic level. The lesions observed in the embryo medaka following Dibutyl-n-phthalate exposure were at or below water solubility and are in agreement with previously reported toxic levels.

  5. Promotion of human adipocyte precursor replication by 17beta-estradiol in culture.

    PubMed Central

    Roncari, D A; Van, R L

    1978-01-01

    The influence of 17beta-estradiol and 17alpha-estradiol on adult human omental adipocyte precursors grown in a propagating culture system was studied. Cells were grown in subculture in the presence or absence of hormone. 17beta-estradiol resulted in significant promotion of adipocyte precursor replication, as determined by cell counting and incorporation of radioactive thymidine into DNA. The hormone stimulated cell multiplication in the concentration range 0.5--500 ng/ml growth medium. The highest level tested was 500 ng/ml. The maximal effects were obtained at 50 ng/ml (P less than 0.001 by paired t test, 48 h after hormone addition). All 10 cell strains (five were derived from men and five from women) that were tested responded similarly to the hormone. 17beta-estradiol did not affect cell size. 17alpha-estradiol did not promote the replication of adipocyte precursors, nor did it influence cell size. Thus, 17beta-estradiol, which is the active isomer in known target tissues, stimulates the multiplication of human adipocyte precursors in culture. Images PMID:690182

  6. Transdermal 17-beta estradiol replacement therapy reduces megakaryocyte GPVI expression.

    PubMed

    Geng, Hongquan; Zhang, Hui; Zhang, Wei; Nieswandt, Bernhard; Bray, Paul F; Leng, Xinghong

    2008-01-01

    The platelet-collagen interaction is a critical early event in arterial thrombus formation, and platelet GPVI is the major activating receptor for collagen. We have previously used a mouse model to demonstrate that the estrogen effects on platelets depend upon the agonist, estrogen formulation and route of administration. In the current study we used a model of transdermal estradiol (E2) administration to ovariectomized mice to address the potential inhibitory effects of E2 on platelet GPVI. Platelet GPVI expression was reduced after transdermal E2 replacement therapy (p E2. In addition, significantly reduced GPVI-mediated fibrinogen binding and aggregation were observed in platelets from mice subjected to 9 days or longer of in vivo E2 treatment, but not in platelets from mice treated for 3 days or shorter, suggesting an indirect pathway. Studies with mouse bone marrow revealed that E2 replacement in ovariectomized mice reduces megakaryocyte GPVI expression. This data suggest that transdermal E2 is able to affect centrally on megakaryocyte GPVI to regulate platelet GPVI and function.

  7. [Bone mineral density and 17 beta-estradiol correlation in postmenopausal women].

    PubMed

    Cárdenas Morales, Beatriz Eugenia; Pérez Campos, Eduardo; Gatica Valdez, Noé

    2004-03-01

    With the increased life-expectancy reached during 20th century, women will spend a very important part of their lives in the estrogenic deficiency state accompanying menopause. To detect serum 17beta-estradiol levels, bone mineral density values, and to see the correlation between both parameters as well as with postmenopausal period. A transversal study with ambulatory, community-dwelling postmenopausal women from Oaxaca de Juárez, Oax. was performed. We studied 70 women with spontaneous menopause, medium values were: age, 55.9 +/- 5.4 yr; menopause age, 48 +/- 3 yr; postmenopausal period, 7.9 +/- 5.3 yr; body mass index, 28.3 +/- 5.4, and serum 17beta-estradiol by radioimmunoassay, 62.78 +/- 25.83 pg/mL. Quantitative calcaneous ultrasound was used to measure bone mineral density and we found 30 women with normal level (-1.0 to 1.4 SD), 29 with osteopenia (-1.1 to -2.3 SD) and only 2 subjects with osteoporosis (-2.7 to 2.8 SD). Statistical analysis shows that bone mineral density and postmenopausal period were significantly correlated (p<0.05) as well as serum 17beta-estradiol levels with postmenopausal period; nevertheless, no correlation between bone mineral density and serum 17beta-estradiol or body mass index (p>0.05) was found. On the other hand, it is remarkable high serum 17beta-estradiol levels found in this group, related with postmenopausal status. These latter results are different from those reported in the literature.

  8. Elevated concentrations of ethinylestradiol, 17beta-estradiol, and medroxyprogesterone have little effect on reproduction and survival of Ceriodaphnia dubia.

    PubMed

    Jukosky, James A; Watzin, Mary C; Leiter, James C

    2008-09-01

    Wastewater effluent contains synthetic and natural hormones, often in complex mixtures, that may be associated with reproductive abnormalities in fish and other aquatic biota. We exposed the sentinel invertebrate Ceriodaphnia dubia to the natural estrogen 17beta-estradiol (E(2)), a synthetic estrogen, ethinylestradiol (EE(2)), and a synthetic progestin, medroxyprogesterone in a 7-day test. These compounds had no significant effect on reproduction or survival even at 10(6) times the concentrations at which reproductive effects have been documented in several fish species. C. dubia is routinely used for screening the toxicity of wastewater effluent. However, in the standard chronic 7-day exposure the endpoints of survival and reproduction were insensitive to several synthetic and natural vertebrate hormones. The C. dubia 7-day chronic toxicity test is probably not a useful monitoring tool for vertebrate hormones and their pharmaceutical analogs unless other sensitive endpoints such as maturation rates, molt frequency, and offspring sex ratios are incorporated in a practical manner.

  9. Lycopene and other carotenoids inhibit estrogenic activity of 17beta-estradiol and genistein in cancer cells.

    PubMed

    Hirsch, Keren; Atzmon, Andrea; Danilenko, Michael; Levy, Joseph; Sharoni, Yoav

    2007-08-01

    Epidemiological evidence suggests that carotenoids prevent several types of cancer, including mammary and endometrial cancers. On the other hand, such studies have also shown that estrogens are the most important risk factors for these cancer types. Genistein, the phytoestrogen mainly found in soy, also shows significant estrogenic activity when tested at concentrations found in human blood. The aim of this study was to determine whether carotenoids inhibit signaling of steroidal estrogen and phytoestrogen which could explain their cancer preventive activity. Similar to the known effect of 17beta-estradiol (E(2)), treatment of breast (T47D and MCF-7) and endometrial (ECC-1) cancer cells with phytoestrogens induced cell proliferation, cell-cycle progression and transactivation of the estrogen response element (ERE). However, each of the tested carotenoids (lycopene, phytoene, phytofluene, and beta-carotene) inhibited cancer cell proliferation induced by either E(2) or genistein. The inhibition of cell growth by lycopene was accompanied by slow down of cell-cycle progression from G1 to S phase. Moreover, the carotenoids inhibited estrogen-induced transactivation of ERE that was mediated by both estrogen receptors (ERs) ERalpha and ERbeta. The possibility that this inhibition results from competition of carotenoid-activated transcription systems on a limited pool of shared coactivators with the ERE transcription system was tested. Although cotransfection of breast and endometrial cancer cells with four different coactivators (SRC-1, SRC-2, SRC-3, and DRIP) strongly stimulated ERE reporter gene activity, it did not oppose the inhibitory effect of carotenoids. These results suggest that dietary carotenoids inhibit estrogen signaling of both 17beta-estradiol and genistein, and attenuate their deleterious effect in hormone-dependent malignancies.

  10. 17beta-Estradiol reduces excitatory postsynaptic potential (EPSP) amplitude in rat basolateral amygdala neurons.

    PubMed

    Womble, Mark D; Andrew, James A; Crook, Joseph J

    2002-10-11

    We examined the actions of estrogen on excitatory synaptic transmission in the basolateral amygdala (BLA), a brain region involved in learning, emotions, and the effects of stress. Intracellular recordings of monosynaptic excitatory postsynaptic potentials (EPSPs) were obtained from BLA neurons in a slice preparation. Bath application of 17beta-estradiol (2 micro M) reduced EPSP amplitude by an average of 77%. This reduction was readily reversed by washing with control saline and was not mimicked by the inactive isomer 17 alpha-estradiol. Other passive and active properties of BLA neurons were unaffected by 17beta-estradiol. The observed EPSP reduction is in sharp contrast to the potentiation of EPSPs by estrogen observed in other brain regions.

  11. Fate and transport of 17beta-estradiol in soil-water systems.

    PubMed

    Casey, Francis X M; Larsen, Gerald L; Hakk, Heldur; Simůnek, Jiri

    2003-06-01

    Over the past several years, there has been an increase in concern regarding reproductive hormones in the environment To date, there exists limited research on the fate and transport of these chemicals in the environment. In this study, a series of laboratory batch sorption and miscible-displacement experiments were done using radiolabeled [14C]17beta-estradiol. The 17beta-estradiol concentrations that were used were similar to those found in manures that are applied to field soils. Equilibrium batch experiments indicated high sorption affinity with correlations to mineral particle size and organic matter content. The sorption affinity appeared to be associated with the surface area and/or the cation-exchange capacity of the soil. The miscible-displacement breakthrough curves indicated chemical nonequilibrium transport, and a single highly polar metabolite was present in the column effluent along with sporadic and trace detections of estriol. Sorbed to the soil within the column were found 17beta-estradiol, estrone, and trace and sporadic detections of estriol. Two chemical nonequilibrium, miscible-displacement models were used to describe the column breakthrough curves; one without transformations and the other with transformations. Both models resulted in excellent descriptions of the data, which indicated nonunique solutions and less confidence in the parameter estimates. Nonetheless, the modeling and experimental results implied that degradation/transformation occurred in the sorbed phase and was rapid. Also, both models indicated that sorption was fully kinetic.

  12. Recognition and effective degradation of 17beta-estradiol by anti-estradiol-antibody-immobilized TiO(2) nanoparticles.

    PubMed

    Ogino, Chiaki; Kanehira, Koki; Sasai, Ryosuke; Sonezaki, Shuji; Shimizu, Nobuaki

    2007-10-01

    Polyelectrolyte polyacrylic acid (PAA), used in the chemical modification of titanium dioxide (TiO(2)) nanoparticles, allows TiO(2) nanoparticles to remain in suspension at neutral pH. The anti-17beta-estradiol (E2) antibody was immobilized on PAA-modified TiO(2) (PAA-TiO(2)) nanoparticles via covalent bonding between the carboxylic acid of PAA and the amino group of the antibody. The anti-E2-antibody-immobilized TiO(2) (E2Ab-PAA-TiO(2)) nanoparticles can form a suspension at neutral pH, with a particle size of less than 100 nm. The E2-PAA-TiO(2) nanoparticles caused the photocatalytic degradation of a typical TiO(2) substrate, methylene blue. The anti-E2 antibody immobilized on the TiO(2) surface recognized and bound E2 in the solution, thereby improving the efficiency of E2 degradation compared with that of PAA-TiO(2) nanoparticles. These results demonstrate that the E2Ab-PAA-TiO(2) nanoparticles developed in this study can be used in water treatment technology. Furthermore, this strategy of immobilizing proteins on nanoscale TiO(2) particles creates new applications not only in the treatment of environmental waste, but also in medical and public sanitation processes.

  13. Differential effect of 17-beta-estradiol on smooth muscle cell and aortic explant MMP2.

    PubMed

    Woodrum, Derek T; Ford, John W; Cho, Brenda S; Hannawa, Kevin K; Stanley, James C; Henke, Peter K; Upchurch, Gilbert R

    2009-07-01

    The present investigation tested the hypothesis that intrinsic gender-related differences exist in rat aortic smooth muscle cell matrix metalloproteinase 2 (MMP2). This investigation comprised 3 sets of experiments. Experiment I: Adult male and female rat aortic smooth muscle cells (RASMCs) at passages 4-8 were stimulated in serum-free media for 48 h with interleukin(IL)1beta at doses encountered in human abdominal aortic aneurysms (2 ng/mL). Messenger RNA was extracted from the RASMCs, and gene expression of MMP2 and tissue inhibitor of metalloproteinase 2 (TIMP2), a major MMP2 inhibitor, was measured by real-time polymerase chain reaction. MMP2 protein levels in conditioned media were measured by Western blotting, and MMP2 and TIMP2 activity quantified by standard and reverse gelatin zymography. Experiment II: Male and female RASMCs were incubated for 48 h in Dulbecco's modified Eagler's medium containing IL-1beta and 17-beta-estradiol at doses from 1x10(-10) to 1x10(-6) molar. MMP2 activity in the conditioned media was then determined. Experiment III: Male rats underwent sustained 17-beta-estradiol exposure for 21 d using extended-release, subcutaneously implanted pellets prior to sacrifice and aortic explantation. Aortas from males, females, and estradiol-treated males were stimulated with IL-1beta for 48-h, and MMP2 activity in the conditioned media was determined. Experiment I: MMP2 gene expression was 3-fold higher in male compared with female IL-1beta stimulated RASMCs (P<0.0001). MMP2:TIMP2 gene expression ratio was 7.5-fold greater in male versus female RASMCs. MMP2 protein levels were 3-fold higher (2.68 versus 0.96 o.d./mg total protein, P=0.003) in male versus female RASMCs. Gelatinolytic activity was more than 6-fold higher (15,010 versus 2,472 o.d./mg total protein, P=0.002) in male versus female RASMCs. Experiment II: MMP2 activity in male and female RASMCs was not altered by a wide range of 17-beta-estradiol concentrations. Experiment III: When

  14. Comparison of three extraction methods for 17beta-estradiol in sand, bentonite, and organic-rich silt loam.

    PubMed

    Chun, Soul; Lee, Jaehoon; Geyer, Roland; White, David C

    2005-01-01

    Extraction is an important procedure for samples that contain soil because other compounds in soil may affect analysis of estrogens. This study was conducted to evaluate three different extraction methods for 17beta-estradiol in soil. Sand, bentonite, and organic-rich silt loam were spiked with 1 mg kg(-1) of 17beta-estradiol as a model compound of estrogens. 17beta-estradiol and its metabolites, estrone and estriol, were extracted using (i) a modified Bligh and Dyer extraction, (ii) a pressurized fluid extraction, and (iii) a diethyl ether extraction, and measured by liquid chromatography tandem mass spectrometry. There were significant differences in the extraction efficiency for 17beta-estradiol among the extraction methods and the soils: the efficiencies ranged from 10% to 97%. Overall, the diethyl ether extraction method had the largest efficiency of 17beta-estradiol with 45% and 57% for bentonite and silt loam, respectively. Transformation of 17beta-estradiol to estrone and estriol in the different extraction methods was less than 3.6% during the extraction procedures. This study underlined the importance of sample preparation for estrogen analysis in soil samples.

  15. Estrogen receptor alpha signaling in inflammatory leukocytes is dispensable for 17beta-estradiol-mediated inhibition of experimental autoimmune encephalomyelitis.

    PubMed

    Garidou, Lucile; Laffont, Sophie; Douin-Echinard, Victorine; Coureau, Christiane; Krust, Andrée; Chambon, Pierre; Guéry, Jean-Charles

    2004-08-15

    Estrogen treatment has been shown to exert a protective effect on experimental autoimmune encephalomyelitis (EAE), and is under clinical trial for multiple sclerosis. Although it is commonly assumed that estrogens exert their effect by modulating immune functions, we show in this study that 17beta-estradiol (E2) treatment can inhibit mouse EAE without affecting autoantigen-specific T cell responsiveness and type 1 cytokine production. Using mutant mice in which estrogen receptor alpha (ERalpha) has been unambiguously inactivated, we found that ERalpha was responsible for the E2-mediated inhibition of EAE. We next generated irradiation bone marrow chimeras in which ERalpha expression was selectively impaired in inflammatory T lymphocytes or was limited to the radiosensitive hemopoietic compartment. Our data show that the protective effect of E2 on clinical EAE and CNS inflammation was not dependent on ERalpha signaling in inflammatory T cells. Likewise, EAE development was not prevented by E2 treatment in chimeric mice that selectively expressed ERalpha in the systemic immune compartment. In conclusion, our data demonstrate that the beneficial effect of E2 on this autoimmune disease does not involve ERalpha signaling in blood-derived inflammatory cells, and indicate that ERalpha expressed in other tissues, such as CNS-resident microglia or endothelial cells, mediates this effect.

  16. Percutaneous 17 beta-estradiol replacement therapy in hypertensive postmenopausal women.

    PubMed

    Osório-Wender, M C; Vitola, D; Spritzer, P M

    1997-09-01

    The present study evaluated the short-term effects of percutaneous 17 beta-estradiol on blood pressure, metabolic profile and hormonal levels in postmenopausal women with systemic arterial hypertension. After a wash-out period of 15 days, 10 hypertensive patients were treated with guanabenz acetate to control blood pressure, followed by 17 beta-estradiol in the form of hydroalcoholic gel administered for 21 of 28 days of each cycle, for 3 cycles. Patients were evaluated before, during and 2 months after estrogen administration. Systolic and diastolic blood pressure or heart rate did not present any significant change in any patient when compared to those periods with the antihypertensive drug only (pretreatment period and 60 days after estrogen therapy was discontinued). Plasma biological markers of hepatic estrogenic action (plasma renin activity, antithrombin III, triglycerides, total cholesterol and lipoproteins) also remained unchanged during the study. Hormone treatment was effective, as indicated by the relief of menopausal symptoms, a decrease in FSH levels (73.48 +/- 27.21 to 35.09 +/- 20.44 IU/l, P < 0.05), and an increase in estradiol levels (15.06 +/- 8.76 to 78.7 +/- 44.6 pg/ml, P < 0.05). There was no effect on LH (18.0 +/- 9.5 to 14.05 +/- 8.28 IU/l). Hormone levels returned to previous values after estrogen treatment was discontinued. The data indicate that short-term percutaneous 17 beta-estradiol replacement therapy, at the dose used, seems to be a safe hormone therapy for hypertensive menopausal women. Nevertheless, a controlled, prospective, randomized clinical assay with a larger number of subjects is needed to definitely establish both the beneficial and harmful effects of hormone replacement therapy in hypertensive women.

  17. Lack of effect of a high-fat meal on the bioavailability of 17 beta-estradiol/norgestimate in healthy postmenopausal women.

    PubMed

    Gisclon, L G; Curtin, C R; Larson, K L; Natarajan, J; Wong, F A; Morrison, D N; Bourg, D

    2000-07-01

    The effect of a high-fat meal on the absorption and pharmacokinetics of 17 beta-estradiol (E2), estrone (E1), estrone sulfate (E1S), and 17-deacetylnorgestimate (17d-NGM) were determined in this two-way complete crossover study of a single dose of E2/NGM (2 mg/180 micrograms) in 24 postmenopausal women. Equal numbers of subjects were randomly assigned to two treatment sequences indicated by the order of fed and fasting treatments. Serial blood samples were collected before and after dosing and assayed using validated methods. Food had no effect on the pharmacokinetics of E2, the pharmacologically active estrogen species. Food increased the rates of formation of E1 and E1S and slowed the formation of 17d-NGM. However, because E1 and E1S are pharmacologically less active metabolites of E2, and since the pharmacokinetic alterations in 17d-NGM were observed over a short time period, these results are probably of no clinical relevance. The extent of formation of all analytes, as measured by AUC, was not affected by food. In conclusion, administration of a tablet containing 17 beta-estradiol/norgestimate (2 mg/180 micrograms) was safe and well tolerated by healthy postmenopausal women and may be given without regard to the timing of meals in relation to dosing.

  18. 17beta-estradiol increases volume, apical surface and elasticity of human endothelium mediated by Na+/H+ exchange.

    PubMed

    Hillebrand, U; Hausberg, M; Stock, C; Shahin, V; Nikova, D; Riethmüller, C; Kliche, K; Ludwig, T; Schillers, H; Schneider, S W; Oberleithner, H

    2006-03-01

    17beta-estradiol is known to delay the onset of atherosclerosis in women but cellular mechanisms are still unclear. Estrogens bind to specific receptors and initiate a signaling cascade that involves the activation of plasma membrane Na(+)/H(+) exchange. We hypothesized that estrogens interfere with ion transport across the plasma membrane and thus control endothelial structure and function. Therefore, we investigated the effects of the sex steroids 17beta-estradiol, progesterone, and testosterone on volume, apical surface and elasticity in human endothelium. The atomic force microscope was used as an imaging tool and as an elasticity sensor. We applied the antiestrogen tamoxifen, the Na(+)/H(+) exchange blocker cariporide and the epithelial Na(+)channel blocker amiloride to elucidate the role of transmembrane ion transport in hormone-treated human umbilical vein endothelial cells (HUVEC). Incubation with 17beta-estradiol for 72 h led to a dose-dependent increase of endothelial cell volume (41%), apical cell surface (22%), and cell elasticity (53%) as compared to non-17beta-estradiol treated controls. Block of the 17beta-estradiol receptor by tamoxifen and of plasma membrane Na(+)/H(+) exchange by cariporide prevented the hormone-induced changes. Progesterone and testosterone were ineffective. 17beta-estradiol increases HUVEC water content and HUVEC elasticity mediated by activated estrogen receptors. The estrogen response depends on the activation of plasma membrane Na(+)/H(+) exchange. The increase in endothelial cell elasticity could be one of the vasoprotective mechanisms postulated for 17beta-estradiol.

  19. Effect of endogenous androgens on 17beta-estradiol-mediated protection after spinal cord injury in male rats.

    PubMed

    Kachadroka, Supatra; Hall, Alicia M; Niedzielko, Tracy L; Chongthammakun, Sukumal; Floyd, Candace L

    2010-03-01

    Several groups have recently shown that 17beta-estradiol is protective in spinal cord injury (SCI). Testosterone can be aromatized to 17beta-estradiol and may increase estrogen-mediated protection. Alternatively, testosterone has been shown to increase excitotoxicity in models of central nervous system (CNS) injury. These experiments test the hypothesis that endogenous testosterone in male rats alters 17beta-estradiol-mediated protection by evaluating a delayed administration over a clinically relevant dose range and manipulating testicular-derived testosterone. Adult male Sprague Dawley rats were either gonadectomized or left gonad-intact prior to SCI. SCI was produced by a midthoracic crush injury. At 30 min post SCI, animals received a subcutaneous pellet of 0.0, 0.05, 0.5, or 5.0 mg of 17beta-estradiol, released over 21 days. Hindlimb locomotion was analyzed weekly in the open field. Spinal cords were collected and analyzed for cell death, expression of Bcl-family proteins, and white-matter sparing. Post-SCI administration of the 0.5- or 5.0-mg pellet improved hindlimb locomotion, reduced urinary bladder size, increased neuronal survival, reduced apoptosis, improved the Bax/Bcl-xL protein ratio, and increased white-matter sparing. In the absence of endogenous testicular-derived androgens, SCI induced greater apoptosis, yet 17beta-estradiol administration reduced apoptosis to the same extent in gonadectomized and gonad-intact male rats. These data suggest that delayed post-SCI administration of a clinically relevant dose of 17beta-estradiol is protective in male rats, and endogenous androgens do not alter estrogen-mediated protection. These data suggest that 17beta-estradiol is an effective therapeutic intervention for reducing secondary damage after SCI in males, which could be readily translated to clinical trials.

  20. Proteomic analysis of MCF-7 breast cancer cell line exposed to mitogenic concentration of 17beta-estradiol.

    PubMed

    Malorni, Livia; Cacace, Giuseppina; Cuccurullo, Manuela; Pocsfalvi, Gabriella; Chambery, Angela; Farina, Annarita; Di Maro, Antimo; Parente, Augusto; Malorni, Antonio

    2006-11-01

    Estrogens are powerful mitogens that play a critical role in the onset of breast cancer and its progression. About two-thirds of all breast cancers are estrogen receptor (ER)+ at the time of diagnosis, and the ER expression is the determinant of a tumor phenotype associated with hormone responsiveness. The molecular basis of the relationship between ER expression, (anti)hormonal responsiveness, and breast cancer prognosis is still unknown. To identify the proteins affected by the presence of the hormone we used 2-D-PAGE-based bottom-up proteomics for the study of the proteome of MCF-7 cells of estrogen-responsive breast carcinoma exposed to a mitogenic concentration of 17beta-estradiol (E2) for 12, 18, 24, and 30 h. Differential expression analysis showed significant changes for 12 proteins. These include ezrin-radixin-moesin-binding phosphoprotein of 50 kDa which was previously shown to be directly regulated by E2. Expression profiles of other proteins already implicated in the progression of breast cancer, such as stathmin, calreticulin, heat shock 71 kDa, alpha-enolase are also described. Moreover, it is observed that different unexpected proteins, translation factors, and energetic metabolism enzymes are also influenced by the presence of the hormone.

  1. A possible alternative to 17beta-estradiol in a viviparous lizard, Tiliqua nigrolutea.

    PubMed

    Edwards, Ashley; Jones, Susan M; Davies, Noel W

    2002-11-01

    We have detected an unusual polar steroid as a major end product of gonadal steroid biosynthesis in male and female blotched blue-tongued lizards, Tiliqua nigrolutea. In an investigation of the steroidogenic pathways in blue-tongued lizards, we incubated gonads of both male and female lizards with tritiated pregnenolone and identified the products of steroid biosynthesis using thin layer chromatography and high performance liquid chromatography with radiometric detection: gonads from both reproductively active and quiescent lizards were examined. The proportion of total radioactive substrate converted to the unknown polar steroid was greater in individuals with hypertrophied gonads (males (N=4) 28.1%; females (N=4) 45.3%) than in those with regressed gonads (males (N=4) 5.9%; females (N=4) 33.3%). Properties of the unknown steroid were identical across all incubations. Incubation time-course information, thin layer and high performance liquid chromatography properties of the polar steroid are presented. The steroid is more polar than 17beta-estradiol, which was not detected, but less polar than all tri-hydroxylated estrogens to which it was compared. The possibility of an alternative estrogen to 17beta-estradiol in some reptiles is discussed.

  2. Development of magnetic particle-based chemiluminescence enzyme immunoassay for the detection of 17beta-estradiol in environmental water.

    PubMed

    Xin, Tian-Bing; Wang, Xu; Jin, Hui; Liang, Shu-Xuan; Lin, Jin-Ming; Li, Zhen-Jia

    2009-09-01

    In the present work, a simple, fast, and highly sensitive chemiluminescence enzyme immunoassay for 17beta-estradiol (E2) in environmental water samples was developed, using magnetic particles (MPs) labeled with secondary antibody as both the immobilization matrix and the separation tools. The specific anti-E2 polyclonal antibody (PcAb) was produced against a conjugate of estradiol-bovine serum albumin. The specificity of the anti-E2 antibody was studied. The results showed that the antibody did not cross-react with the structurally related endocrine-disrupting compounds, including estrone, ethinyl E2, estriol, E2-17-glucuronide, E2-3-sulfate-17-glucuronide, androstenedione, and dihydrotestosterone. The water samples were pretreated with solid-phase extraction using C18 cartridges for the removal of matrix effects. Several physicochemical parameters including the dilution ratios of E2-6-horseradish peroxidase conjugate and anti-E2 PcAb, immunoreaction time, volume of chemiluminescent substrate and MPs, chemiluminescence reaction time, and pH of assay solution were studied and optimized. At optimal experimental conditions, it was found that the proposed method exhibited high performance with detection limit of 2.0 pg/mL, linear range of 20-1,200 pg/mL, and total assay time of 45 min. Both inter- and intra-assay coefficient of variation were less than 10%. The average recoveries of three different spiked concentration samples ranged from 86.3% to 108%. The method was successfully applied to the determination of E2 in river, waste, and tap water, and showed a good correlation with the commercially available radioimmunoassay kit.

  3. Gene expression responses of European flounder (Platichthys flesus) to 17-beta estradiol.

    PubMed

    Williams, Tim D; Diab, Amer M; George, Stephen G; Sabine, Victoria; Chipman, James K

    2007-02-05

    Male European flounder (Platichthys flesus) were intraperitoneally injected with 10mg/kg 17-beta estradiol and tissues taken from individuals over a timecourse of 16 days. The GENIPOL P. flesus cDNA microarray was employed to detect hepatic gene expression differences between fish treated with estradiol and saline controls. Known biomarkers of estrogen exposure, choriogenin L and vitellogenins, showed sustained induction over the time-course. Among 175 identified clones showing sustained statistically significant induction or repression, those associated with the Gene Ontology terms mitochondria, amino acid synthesis, ubiquitination and apoptosis were included amongst those induced while those associated with immune function, electron transport, cell signalling and protein phosphorylation were repressed. Thus, we show the gene expression response of an environmentally relevant fish species to a high dose of an estrogenic endocrine disruptor and also report the sequencing of a further 2121 flounder ESTs.

  4. Exercise, sex, menstrual cycle phase, and 17beta-estradiol influence metabolism-related genes in human skeletal muscle.

    PubMed

    Fu, Ming-hua H; Maher, Amy C; Hamadeh, Mazen J; Ye, Changhua; Tarnopolsky, Mark A

    2009-12-30

    Higher fat and lower carbohydrate and amino acid oxidation are observed in women compared with men during endurance exercise. We hypothesized that the observed sex difference is due to estrogen and that menstrual cycle phase or supplementation of men with 17beta-estradiol (E(2)) would coordinately influence the mRNA content of genes involved in lipid and/or carbohydrate metabolism in skeletal muscle. Twelve men and twelve women had muscle biopsies taken before and immediately after 90 min of cycling at 65% peak oxygen consumption (Vo(2peak)). Women were studied in the midfollicular (Fol) and midluteal (Lut) phases, and men were studied after 8 days of E(2) or placebo supplementation. Targeted RT-PCR was used to compare mRNA content for genes involved in transcriptional regulation and lipid, carbohydrate, and amino acid metabolism. Sex was the greatest predictor of substrate metabolism gene content. Sex affected the mRNA content of FATm, FABPc, SREBP-1c, mtGPAT, PPARdelta, PPARalpha, CPTI, TFP-alpha, GLUT4, HKII, PFK, and BCOADK (P < 0.05). E(2) administration significantly (P < 0.05) affected the mRNA content of PGC-1alpha, PPARalpha, PPARdelta, TFP-alpha, CPTI, SREBP-1c, mtGPAT, GLUT4, GS-1, and AST. Acute exercise increased the mRNA abundance for PGC-1alpha, HSL, FABPc, CPTI, GLUT4, HKII, and AST (P < 0.05). Menstrual cycle had a small effect on PPARdelta, GP, and glycogenin mRNA content. Overall, women have greater mRNA content for several genes involved in lipid metabolism, which is partially due to an effect of E(2).

  5. Mammary tumor induction in ACI rats exposed to low levels of 17beta-estradiol.

    PubMed

    Ravoori, Srivani; Vadhanam, Manicka V; Sahoo, Sunati; Srinivasan, Cidambi; Gupta, Ramesh C

    2007-07-01

    Animal models play a major role in understanding the etiology, molecular mechanisms, strategizing intervention and treatment of human diseases. ACI, an inbred line derived from August and Copenhagen strains, is unique for its susceptibility to estrogen-induced mammary tumors. Histologically and in many molecular aspects, the tumors formed in these rats are similar to human breast cancers. Previous studies have shown high mortality and significant weight loss in this model associated with pituitary gland abnormality. We hypothesized that this could be due to overwhelming the biological system with estrogen. Three groups of female ACI rats (7-8 weeks) received either 3-cm sham silastic implants, or the conventional 3-cm silastic implants containing 27 mg of 17beta-estradiol, or 1.2-cm silastic implants containing 9 mg 17beta-estradiol. The sham and 3-cm implant rats were euthanized at 180 days while the 1.2-cm implant rats were euthanized at 240 days. The 1.2-cm implants resulted in significantly reduced serum estrogen levels and pituitary gland size. Animals with 1.2-cm implants had 100% tumor incidence, while not all rats developed tumors with 3-cm implants. Both the tumor burden (from 1,011+/-402 to 2,324+/-454 mm(3); p=0.01) and tumor multiplicity (from 5.78+/-1.4 to 7.6+/-1.04) increased by lowering the estrogen dose, and the inter-animal variability in the tumor indices decreased. Finally, the weight of the pituitary gland was also significantly (p=0.0004) reduced (from 178+/-23.5 mg to 80+/-8.9 mg) and the mortality rate decreased from 42% to 0% (p=0.01). Our data indicate that the improvised model will provide valuable insights into the molecular alterations in the estrogen-induced mammary tumorigenesis and will be ideal for inhibition studies.

  6. Oral hormone therapy with 17beta-estradiol and 17beta-estradiol in combination with norethindrone acetate in the prevention of bone loss in early postmenopausal women: dose-dependent effects.

    PubMed

    Greenwald, Maria W; Gluck, Oscar S; Lang, Eva; Rakov, Viatcheslav

    2005-01-01

    A 2-year multicenter, double-blind, randomized, placebo-controlled study examined the efficacy and safety of different doses of 17beta-estradiol (E(2)) alone and continuous-combined oral formulations of E(2) and norethindrone acetate (NETA) versus placebo in the prevention of bone loss in newly menopausal women. Patients were randomized to one of seven groups: placebo, E(2) 0.25 mg, E2 0.5 mg, E(2) 1 mg, E(2) 1 mg/NETA 0.25 mg, E(2) 1 mg/NETA 0.5 mg, or E(2) 2 mg/NETA 1 mg. Treatment was a once-daily tablet taken for 26 months. The primary efficacy endpoint was the change in bone mineral density (BMD) at the lumbar spine, measured by dual-energy x-ray absorptiometry, at screening and at 13, 19, and 26 months. BMD changes at the femoral neck and trochanter were also assessed. Biochemical markers of bone metabolism were measured at baseline, and at 3, 6, 13, 19, and 26 months. Histological diagnoses of endometrial samples were tabulated for each treatment group. A total of 327 women were randomized and 189 women completed the 2-year trial. BMD at the lumbar spine decreased 2.3% in the placebo group. The lowest dose of unopposed E(2) prevented bone loss at the spine and hip. Significant increases in spine BMD compared with placebo occurred in all groups of treatment with E(2) and were more pronounced in the combination groups. Compared with placebo, women receiving active treatment experienced greater reductions in bone resorption markers. The effects were evident by 6 months and generally remained stable thereafter. Adverse events, primarily associated with the endometrium, were the most common reasons for discontinuation. There is a dose-dependent effect of E(2) on BMD. The addition of NETA seems to enhance the response in BMD observed with E(2). Low doses of E(2) (1 mg and lower) can be considered for the prevention of osteoporosis, while titrating the hormone dose to individual patient's needs.

  7. Antidepressant-like effect of 17beta-estradiol: involvement of dopaminergic, serotonergic, and (or) sigma-1 receptor systems.

    PubMed

    Dhir, Ashish; Kulkarni, S K

    2008-10-01

    17beta-estradiol has been reported to possess antidepressant-like activity in animal models of depression, although the mechanism for its effect is not well understood. The present study is an effort in this direction to explore the mechanism of the antidepressant-like effect of 17beta-estradiol in a mouse model(s) of behavioral depression (despair behavior). Despair behavior, expressed as helplessness to escape from a situation (immobility period), as in a forced swim test in which the animals are forced to swim for a total of 6 min, was recorded. The antiimmobility effects (antidepressant-like) of 17beta-estradiol were compared with those of standard drugs like venlafaxine (16 mg/kg, i.p.). 17beta-estradiol produced a U-shaped effect in decreasing the immobility period. It had no effect on locomotor activity of the animal. The antidepressant-like effect was comparable to that of venlafaxine (16 mg/kg, i.p.). 17beta-estradiol also exhibited a similar profile of antidepressant action in the tail suspension test. When coadministered with other antidepressant drugs, 17beta-estradiol (5 microg/kg, i.p.) potentiated the antiimmobility effect of subeffective doses of fluoxetine (5 mg/kg, i.p.), venlafaxine (2 mg/kg, i.p.), or bupropion (10 mg/kg, i.p.), but not of desipramine (5 mg/kg, i.p.) or tranylcypromine (2 mg/kg, i.p.), in the forced swim test. The reduction in the immobility period elicited by 17beta-estradiol (20 microg/kg, i.p.) was reversed by haloperidol (0.5 mg/kg, i.p.; a D(2) dopamine receptor antagonist), SCH 23390 (0.5 mg/kg, i.p.; a D(1) dopamine receptor antagonist), and sulpiride (5 mg/kg, i.p.; a specific dopamine D(2) receptor antagonist). In mice pretreated with (+)-pentazocine (2.5 mg/kg, i.p.; a high-affinity sigma-1 receptor agonist), 17beta-estradiol (5 microg/kg, i.p.) produced a synergistic effect. In contrast, pretreatment with progesterone (10 mg/kg, s.c.; a sigma-1 receptor antagonist neurosteroid), rimcazole (5 mg/kg, i.p.; another sigma

  8. Modulation of serum concentrations and hepatic metabolism of 17beta-estradiol and testosterone by amitraz in rats.

    PubMed

    Chou, Chen-Ping; Lu, Shui-Yuan; Ueng, Tzuu-Huei

    2008-10-01

    The present study has investigated the ability of amitraz, a widely used formamidine pesticide, to modulate serum concentrations and liver microsomal metabolism of 17beta-estradiol (E2) and testosterone in rats. Amitraz was administered intraperitoneally to male rats for 4 days and to intact female rats or ovariectomized (OVX) and 0.5 mg/kg E2-supplemented female rats for 7 days. E2 and metabolites were analyzed by gas chromatography-electron capture detection and testosterone and metabolites were analyzed by high-pressure liquid chromatography. In OVX and E2-supplemented females, 50 mg/kg amitraz caused an 85% decrease of serum E2 concentration and a marked increase of 2-OH-E2 concentration. Amitraz at 25 and 50 mg/kg produced 9.0-fold or greater increases of serum testosterone and 2beta-OH-testosterone levels in males. Amitraz at 25 mg/kg resulted in no or minimal increases of liver microsomal formation of E2 or testosterone metabolites. Amitraz at 50 mg/kg produced 1.4- to 3.6-fold increases of 2-OH-E2; estrone; 2beta-, 6beta-, and 16alpha-OH-testosterone; and androstenedione formation in males and intact females. Amitraz at 50 mg/kg preferentially increased intact female 16beta-OH-testosterone production by 8.6-fold. In OVX females, E2 supplement alone or cotreatment with E2 and 50 mg/kg amitraz produced 1.3- to several-fold increases of 2- and 4-OH-E2 formation and 2beta- and 16alpha-OH-testosterone production. The cotreatment increased 6beta- and 16beta-OH-testosterone formation by 1.8- and 1.6-fold, respectively. The present findings show that amitraz induces hepatic E2 and testosterone metabolism in male and female rats, decreases serum E2 concentration in OVX and E2-supplemented females, but increases serum testosterone in males.

  9. 17beta-estradiol deficiency reduces potassium excretion in an angiotensin type 1 receptor-dependent manner.

    PubMed

    Ji, Hong; Zheng, Wei; Falconetti, Celine; Roesch, Darren M; Mulroney, Susan E; Sandberg, Kathryn

    2007-07-01

    This study examined the effects of ovariectomy (OVX) and 17beta-estradiol (E(2)) replacement (OVX + E(2)) on renal function in Sprague-Dawley rats. OVX caused a 40% decrease in the fractional excretion of potassium (FE(K(+))) that was prevented by E(2) replacement [Sham, 24.2 +/- 2.9%; OVX, 14.5 +/- 2.1% (P < 0.05 vs. OVX + E(2)); and OVX + E(2), 26.2 +/- 2.7%; n = 7-11] and that corresponded to significant increases in plasma potassium [(in mmol/l): Sham, 3.15 +/- 0.087; OVX, 3.42 +/- 0.048 (P < 0.05 vs. OVX + E(2)); and OVX + E(2), 3.19 +/- 0.11; n = 7-11]. No effects of OVX were detected on plasma levels of sodium and aldosterone. Angiotensin II type 1 receptor (AT(1)R) densities in ovariectomized rats were 1.4-fold and 1.3-fold higher in glomerular [maximum binding capacity (B(max); in fmol/mg protein): Sham, 482 +/- 21; OVX, 666 +/- 20 (P < 0.05 vs. OVX + E(2)); and OVX + E(2), 504 +/- 26; n = 7-11] and proximal tubular [B(max) (in fmol/mg protein): Sham, 721 +/- 16; OVX, 741 +/- 24 (P < 0.05 vs. OVX + E(2)); and OVX + E(2), 569 +/- 23; n = 7-11] membranes compared with E(2) replete animals, respectively. Both the angiotensin-converting enzyme inhibitor captopril and the AT(1)R antagonist losartan prevented the OVX-induced decrease in the FE(K(+)) and the increase in renal AT(1)R densities, suggesting that E(2) deficiency reduces potassium excretion in an ANG II/AT(1)R-dependent manner. These findings may have implications for renal function in postmenopausal women as well as contribute to the reasons underlying the age-induced increase in susceptibility to hypertension-associated disease in women.

  10. 17beta-estradiol corrects hemostasis in uremic rats by limiting vascular expression of nitric oxide synthases.

    PubMed

    Noris, M; Todeschini, M; Zappella, S; Bonazzola, S; Zoja, C; Corna, D; Gaspari, F; Marchetti, G; Aiello, S; Remuzzi, G; Marchetti, F

    2000-10-01

    Conjugated estrogens shorten the prolonged bleeding time in uremic patients and are similarly effective in a rat model of uremia. We have previously demonstrated that the shortening effect of a conjugated estrogen mixture or 17beta-estradiol on bleeding time was abolished by the nitric oxide (NO) precursor L-arginine, suggesting that the effect of these drugs on hemostasis in uremia might be mediated by changes in the NO synthetic pathway. The present study investigated the biochemical mechanism(s) by which conjugated estrogens limit the excessive formation of NO. 17beta-estradiol (0.6 mg/kg), given to rats made uremic by reduction of renal mass, significantly reduced bleeding time within 24 h and completely normalized plasma concentrations of the NO metabolites, nitrites and nitrates, and of NO synthase (NOS) catalytic activity, determined by NADPH-diaphorase staining in the thoracic aorta. Endothelial NOS (ecNOS) and inducible NOS (iNOS) immunoperoxidase staining in the endothelium of uremic aortas of untreated rats was significantly more intense than in control rats, while in uremic rats receiving 17beta-estradiol staining was comparable to controls. Thus 17beta-estradiol corrected the prolonged bleeding time of uremic rats and fully normalized the formation of NO by reducing the expression of ecNOS and iNOS in vascular endothelium. These results provide a possible biochemical explanation of the well-known effect of estrogens on primary hemostasis in uremia, in experimental animals and humans.

  11. Enhancement of dendritic branching in cultured hippocampal neurons by 17beta-estradiol is mediated by nitric oxide.

    PubMed

    Audesirk, T; Cabell, L; Kern, M; Audesirk, G

    2003-06-01

    Both 17beta-estradiol (E2) and nitric oxide (NO) are important in neuronal development, learning and memory, and age-related memory changes. There is growing evidence that a number of estrogen receptor-mediated effects of estradiol utilize nitric oxide as an intermediary. The role of estradiol in hippocampal neuronal differentiation and function has particular implications for learning and memory. Low levels of estradiol (10nM) significantly increase dendritic branching in cultured embryonic rat hippocampal neurons (158% of control). This study investigates the hypothesis that the estrogen-stimulated increase in dendritic branching is mediated by nitric oxide. We found that nitric oxide donors also produce significantly increased dendritic branching S-nitroso-N-acetylpenicillamine (SNAP: 119%; 2,2'-(hydroxynitrosohydrazino)bis-ethanamine (NOC-18): 128% of control). We then determined that the increases in dendritic branching stimulated by estradiol or by a nitric oxide donor were both blocked by an inhibitor of guanylyl cyclase. Dendritic branching was also stimulated by a cell permeable analog of cyclic guanosine monophosphate (dibutyryl-cGMP: 173% of control). Estradiol-stimulated dendritic branching was reversed by the nitric oxide scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethyl imidazoline-1-oxyl 3-oxide (carboxy-PTIO). This study provides evidence that estradiol influences the development of embryonic hippocampal neurons in culture by increasing the production of nitric oxide or by increasing the sensitivity of the neurons to nitric oxide. Nitric oxide in turn stimulates dendritic branching via activation of guanylyl cyclase.

  12. 17beta-estradiol potently suppresses cAMP-induced insulin-like growth factor-I gene activation in primary rat osteoblast cultures

    NASA Technical Reports Server (NTRS)

    McCarthy, T. L.; Ji, C.; Shu, H.; Casinghino, S.; Crothers, K.; Rotwein, P.; Centrella, M.

    1997-01-01

    Insulin-like growth factor-I (IGF-I) is a key factor in bone remodeling. In osteoblasts, IGF-I synthesis is enhanced by parathyroid hormone and prostaglandin E2 (PGE2) through cAMP-activated protein kinase. In rats, estrogen loss after ovariectomy leads to a rise in serum IGF-I and an increase in bone remodeling, both of which are reversed by estrogen treatment. To examine estrogen-dependent regulation of IGF-I expression at the molecular level, primary fetal rat osteoblasts were co-transfected with the estrogen receptor (hER, to ensure active ER expression), and luciferase reporter plasmids controlled by promoter 1 of the rat IGF-I gene (IGF-I P1), used exclusively in these cells. As reported, 1 microM PGE2 increased IGF-I P1 activity by 5-fold. 17beta-Estradiol alone had no effect, but dose-dependently suppressed the stimulatory effect of PGE2 by up to 90% (ED50 approximately 0.1 nM). This occurred within 3 h, persisted for at least 16 h, required ER, and appeared specific, since 17alpha-estradiol was 100-300-fold less effective. By contrast, 17beta-estradiol stimulated estrogen response element (ERE)-dependent reporter expression by up to 10-fold. 17beta-Estradiol also suppressed an IGF-I P1 construct retaining only minimal promoter sequence required for cAMP-dependent gene activation, but did not affect the 60-fold increase in cAMP induced by PGE2. There is no consensus ERE in rat IGF-I P1, suggesting novel downstream interactions in the cAMP pathway that normally enhances IGF-I expression in skeletal cells. To explore this, nuclear extract from osteoblasts expressing hER were examined by electrophoretic mobility shift assay using the atypical cAMP response element in IGF-I P1. Estrogen alone did not cause DNA-protein binding, while PGE2 induced a characteristic gel shift complex. Co-treatment with both hormones caused a gel shift greatly diminished in intensity, consistent with their combined effects on IGF-I promoter activity. Nonetheless, hER did not bind

  13. 17beta-estradiol potently suppresses cAMP-induced insulin-like growth factor-I gene activation in primary rat osteoblast cultures

    NASA Technical Reports Server (NTRS)

    McCarthy, T. L.; Ji, C.; Shu, H.; Casinghino, S.; Crothers, K.; Rotwein, P.; Centrella, M.

    1997-01-01

    Insulin-like growth factor-I (IGF-I) is a key factor in bone remodeling. In osteoblasts, IGF-I synthesis is enhanced by parathyroid hormone and prostaglandin E2 (PGE2) through cAMP-activated protein kinase. In rats, estrogen loss after ovariectomy leads to a rise in serum IGF-I and an increase in bone remodeling, both of which are reversed by estrogen treatment. To examine estrogen-dependent regulation of IGF-I expression at the molecular level, primary fetal rat osteoblasts were co-transfected with the estrogen receptor (hER, to ensure active ER expression), and luciferase reporter plasmids controlled by promoter 1 of the rat IGF-I gene (IGF-I P1), used exclusively in these cells. As reported, 1 microM PGE2 increased IGF-I P1 activity by 5-fold. 17beta-Estradiol alone had no effect, but dose-dependently suppressed the stimulatory effect of PGE2 by up to 90% (ED50 approximately 0.1 nM). This occurred within 3 h, persisted for at least 16 h, required ER, and appeared specific, since 17alpha-estradiol was 100-300-fold less effective. By contrast, 17beta-estradiol stimulated estrogen response element (ERE)-dependent reporter expression by up to 10-fold. 17beta-Estradiol also suppressed an IGF-I P1 construct retaining only minimal promoter sequence required for cAMP-dependent gene activation, but did not affect the 60-fold increase in cAMP induced by PGE2. There is no consensus ERE in rat IGF-I P1, suggesting novel downstream interactions in the cAMP pathway that normally enhances IGF-I expression in skeletal cells. To explore this, nuclear extract from osteoblasts expressing hER were examined by electrophoretic mobility shift assay using the atypical cAMP response element in IGF-I P1. Estrogen alone did not cause DNA-protein binding, while PGE2 induced a characteristic gel shift complex. Co-treatment with both hormones caused a gel shift greatly diminished in intensity, consistent with their combined effects on IGF-I promoter activity. Nonetheless, hER did not bind

  14. Primary induction of vitellogenin mRNA in the rooster by 17beta-estradiol.

    PubMed Central

    Burns, A T; Deeley, R G; Gordon, J I; Udell, D S; Mullinix, K P; Goldberger, R F

    1978-01-01

    We have studied the kinetics of vitellogenin mRNA accumulation in rooster liver after a primary injection of 17beta-estradiol. The levels of vitellogenin mRNA have been determined both by hybridization of total cellular RNA to vitellogenin cDNA and by translation of vitellogenin mRNA in a wheat germ cell-free system. The results obtained by both methods of analysis are in good agreement and indicate that vitellogenin mRNA is present in the liver of normal roosters at a level of 0-5 molecules per liver cell and increases in amount during the 3 days following injection of estrogen, reaching a level of almost 6000 molecules per cell at the peak of the response. The level of vitellogenin mRNA declined exponentially during the next 14 days with a half-life of 29 hr, reaching a level of less than 10 molecules per cell at 17 days after injection of the hormone. The levels of vitellogenin mRNA after stimulation with estrogen have been correlated with the in vivo rate of synthesis of the vitellogenin polypeptide. The results indicate that the rate of vitellogenin synthesis is closely correlated with the level of vitellogenin mRNA. On the basis of these findings, we conclude that vitellogenin mRNA does not exist in the liver in an untranslated form after withdrawal from estrogen. PMID:273910

  15. Formation of catechol estrogen glutathione conjugates and gamma-glutamyl transpeptidase-dependent nephrotoxicity of 17beta-estradiol in the golden Syrian hamster.

    PubMed

    Butterworth, M; Lau, S S; Monks, T J

    1997-03-01

    In an animal model of hormone-mediated carcinogenesis, male golden Syrian hamsters develop renal carcinoma following prolonged exposure to 17beta-estradiol. The basis for the species and tissue specificity is unclear. Detailed information on the disposition of 17beta-estradiol in this model is lacking. Because catechol estrogens have been implicated in this model of carcinogenesis, we investigated the metabolism and nephrotoxicity of 17beta-estradiol in golden Syrian hamsters, with emphasis on the formation of catechol estrogen thioethers. 17beta-Estradiol (50 micromol/kg, i.p.) is a mild nephrotoxicant, causing significant elevations in the urinary excretion of gamma-glutamyl transpeptidase (gamma-GT), alkaline phosphatase, glutathione S-transferase (GST) and glucose. Increases in renal protein carbonyls and lipid hydroperoxides, which are markers of oxidative damage, also occur after administration of 17beta-estradiol (50 micromol/kg, i.p.). 17beta-Estradiol-mediated nephrotoxicity is reduced by treating animals with acivicin, an inhibitor of gamma-GT, implying that toxicity is mediated by metabolites requiring metabolism by this enzyme. Following administration of 17beta-[14C]estradiol (100 micromol/kg) to hamsters, 9.7% of the dose is recovered in bile after 5 h, the majority (7.9%) representing aqueous metabolites. Seven catechol estrogen GSH conjugates were identified, 2-hydroxy-1,4-bis-(glutathion-S-yl)-17beta-estradiol, 2-hydroxy-4-(glutathion-S-yl)-17beta-estradiol, 2-hydroxy-4-(glutathion-S-yl)-estrone, 4-hydroxy-1-(glutathion-S-yl)-estrone, 2-hydroxy-1-(glutathion-S-yl)-estrone, 4-hydroxy-1-(glutathion-S-yl)-17beta-estradiol, and 2-hydroxy-1-(glutathion-S-yl)-17beta-estradiol. At 5.4 micromol/kg of 17beta-estradiol, a dose-reflective of daily exposure levels in the hamster model of nephrocarcinogenicity, 12% of the dose is recovered within 5 h as a combination of GSH conjugates of 2- and 4-hydroxy-17beta-estradiol and 2- and 4-hydroxyestrone. In summary

  16. 17beta-estradiol treatment decreases steroidogenic enzyme messenger ribonucleic acid levels in the rainbow trout testis.

    PubMed

    Govoroun, M; McMeel, O M; Mecherouki, H; Smith, T J; Guiguen, Y

    2001-05-01

    In fish, estrogens are well known for their involvement in ovarian differentiation and have been shown to be very potent feminizing agents when administrated in vivo during early development. However, the mechanism of action of exogenous estrogens is poorly understood. We report here on the feminizing effects of estrogen treatment on the testicular levels of some steroidogenic enzyme messenger RNAs [mRNAs; cholesterol side-chain cleavage (P450scc), 17-hydroxylase/lyase (P450c17), 3beta-hydroxysteroid dehydrogenase (3betaHSD), 11beta-hydroxylase (P45011beta), and aromatase (P450aro)] in the rainbow trout, Oncorhynchus mykiss. Treatment was carried out by dietary administration of 17beta-estradiol (E(2); dosage of 20 mg/kg diet) to a genetically all male population. Steroidogenesis in the differentiating testis was demonstrated to be strongly altered by E(2), as this treatment resulted in considerable decrease in P450c17, 3betaHSD, and P45011beta mRNAs after only 10 days of treatment. In contrast, P450scc and P450aro mRNA levels were unaffected by E(2), with P450scc mRNA levels remaining unaltered and P450aro not stimulated by this feminizing estrogen treatment. To better characterize this E(2) effect, the same treatment was applied on postdifferentiating males, and roughly the same expression pattern was detected with a considerable decrease in testicular P450c17, 3betaHSD, and P45011beta mRNAs and a significant, but reduced, decrease in P450scc mRNA. In the interrenal, these steroidogenic enzyme mRNAs were not significantly affected by this E(2) treatment, except for a slight, but significant, decrease in P450scc mRNA. These results clearly demonstrate that estrogens have profound effects on testicular steroidogenesis and that they are acting specifically on the testis by decreasing mRNA steady state levels of many steroidogenic enzyme genes. The decrease in P45011beta mRNA, and thus inhibition of the synthesis of testicular 11-oxygenated androgens, may be an

  17. Effects of octylphenol and 17beta-estradiol on the gonads of guppies (Poecilia reticulata) exposed as adults via the water or as embryos via the mother.

    PubMed

    Kinnberg, Karin; Korsgaard, Bodil; Bjerregaard, Poul

    2003-01-01

    Endocrine disrupting alkylphenolic compounds have been found in the aquatic environment, and concern has arisen over the ability of these compounds to affect the reproductive system of fish. In this study, the effects of exposure to an environmentally relevant concentration of octylphenol or 17beta-estradiol on the gonad structure of fish were examined. Viviparous guppies (Poecilia reticulata) were exposed as adults via the water or as embryos via the mother to 26 microg/l octylphenol or 0.85 microg/l 17beta-estradiol (mean measured water concentrations). Histological examinations revealed effects of the exposures on the gonads of the fish exposed as adults. Indications of blocked spermatogonial mitosis were seen in the testis structure of adult males after exposure to octylphenol or 17beta-estradiol. The post-parturition ovaries of adult females exposed to 17beta-estradiol showed effects suggesting an inhibited yolk deposition. At the tested concentrations, exposure to octylphenol or 17beta-estradiol via the mother fish did not significantly affect the weight, length, gonopodium index or sex distribution of the offspring. However, histology revealed effects on the liver structure, suggesting some effect of maternal exposure to octylphenol or 17beta-estradiol. These findings indicate that although octylphenol and 17beta-estradiol affect the gonad structure of adult male and female guppies, these substances have no significant effects on the sexual differentiation of the embryos at the tested concentrations.

  18. Assessment of Neuroprotective Effects of Local Administration of 17- Beta- Estradiol on Peripheral Nerve Regeneration in Ovariectomized Female Rats

    PubMed Central

    Nobakhti-Afshar, Ahmadreza; Najafpour, Alireza; Mohammadi, Rahim; Zarei, Leila

    2016-01-01

    Objective: To assess the neuroprotective effects of local administration of 17- beta- estradiol on nerve regeneration. Methods: Sixty female Wistar rats were overiectomized and divided into four experimental groups (n = 15), randomly: In autograft group a segment of sciatic nerve was transected and re-implanted reversely. In sham-surgery group sciatic nerve was exposed and manipulated. In transected group left sciatic nerve was transected and stumps were fixed in adjacent muscle. In treatment group defect was bridged using a silicon conduit filled with 10 µL (0.1 mg/mL) 17- beta- estradiol. Each group was subdivided into four subgroups of five animals each and nerve fibers were studied in a 12-week period. Results: Behavioral, functional, biomechanical, electrophysiological and gastrocnemius muscle mass findings and morphometric indices confirmed faster recovery of regenerated axons in treatment group than in other groups (p<0.05). Immunohistochemical reactions to S-100 in treatment group were more positive than that in other groups. Conclusion: Local administration of 17-beta-estradiol improved functional recovery and morphometric indices of sciatic nerve. It could have clinical implications for the surgical management of patients after facial nerve transection. PMID:27540548

  19. Seasonal variations of fecal progesterone and 17beta-estradiol in captive female black-handed spider monkeys (Ateles geoffroyi).

    PubMed

    Cerda-Molina, A L; Hernández-López, L; Páez-Ponce, D L; Rojas-Maya, S; Mondragón-Ceballos, R

    2006-11-01

    A number of studies in free-ranging and captive spider monkeys (Ateles spp.) have shown that this genus is able to reproduce throughout the entire year. Nonetheless, it is still controversial whether births, and therefore conceptions, tend to be more frequent during certain seasons. In the present study, we monitored changes in fecal 17beta-estradiol and progesterone for approximately 1 years in five female black-handed spider monkeys (Ateles geoffroyi) kept in captivity in Mexico City. The objective was to determine whether hormone concentrations and menstrual cycles of summer and autumn accounted for a greater chance of conception than those of winter and spring, consistent with birth patterns previously reported. We collected fecal samples from the five monkeys almost daily for 1 year (March 2004 to February 2005) and used radioimmunoassay of fecal extracts to determine concentrations of 17beta-estradiol and progesterone. Concurrently, menstrual cycle phases were determined by cytological evaluation of vaginal swabs. Periovulatory 17beta-estradiol concentrations were significantly higher in autumn than in winter, spring or summer. Moreover, as evidenced by progesterone peaks, most of the summer-autumn menstrual cycles were ovulatory; in contrast, most of the winter and spring cycles were anovulatory. In conclusion, our data supported the notion that, although not a strictly seasonal reproducer, the black-handed spider monkey is more likely to conceive at the end of the rainy season and throughout autumn.

  20. Effect of 17 beta-estradiol on somatic and germ cell subpopulations in the ovary of the newly hatched chick.

    PubMed

    Méndez-Herrera, C; Hofmann, P; Pedernera, E

    1993-02-01

    The involvement of estrogens in avian ovary differentiation and morphogenesis has been previously demonstrated by several authors. The aim of the present study is to provide evidence regarding which cell subpopulations of the ovary are target cells for 17 beta-estradiol during chick development. White Leghorn chick embryos received 200 ng of the hormone or the vehicle on the chorioallantoic membrane at 11, 13, and 15 days of incubation. Within 24 hr after hatching, the left ovary was processed for total cell count, study of the meiotic prophase of oocytes, and the morphometric evaluation of the cortical and the medullary regions of the ovary. Germ cell number was not modified by the treatment. Similarly, no changes were observed in the stage of the prophase and the cellular area of oocytes. The total number of somatic cells was increased in the newly hatched chick ovary treated with 17 beta-estradiol. The number of undifferentiated cells in the juxtacortical medulla was higher in the treated ovary than in the control group. Moreover, the pregranulosa cells of the cortical region were hypertrophied in the 17 beta-estradiol treated ovary. However, no changes were observed in the typical steroidogenic cells after the estrogen treatment. In conclusion, two subpopulations of somatic cells are estrogen target cells in the prefollicular chicken ovary: the pregranulosa cells of the ovarian cortex and the undifferentiated cells in the juxtacortical medulla.

  1. Acute treatment with 17beta-estradiol attenuates astrocyte-astrocyte and astrocyte-neuron communication.

    PubMed

    Rao, Shilpa P; Sikdar, Sujit Kumar

    2007-12-01

    Astrocytes are now recognized as dynamic signaling elements in the brain. Bidirectional communication between neurons and astrocytes involves integration of neuronal inputs by astrocytes and release of gliotransmitters that modulate neuronal excitability and synaptic transmission. The ovarian steroid hormone, 17beta-estradiol, in addition to its rapid actions on neuronal electrical activity can rapidly alter astrocyte intracellular calcium concentration ([Ca2+]i) through a membrane-associated estrogen receptor. Using calcium imaging and electrophysiological techniques, we investigated the functional consequences of acute treatment with estradiol on astrocyte-astrocyte and astrocyte-neuron communication in mixed hippocampal cultures. Mechanical stimulation of an astrocyte evoked a [Ca2+]i rise in the stimulated astrocyte, which propagated to the surrounding astrocytes as a [Ca2+]i wave. Following acute treatment with estradiol, the amplitude of the [Ca2+]i elevation in astrocytes around the stimulated astrocyte was attenuated. Further, estradiol inhibited the [Ca2+]i rise in individual astrocytes in response to the metabotropic glutamate receptor agonist, trans-(+/-)-1-amino-1,3-cyclopentanedicarboxylic acid. Mechanical stimulation of astrocytes induced [Ca2+]i elevations and electrophysiological responses in adjacent neurons. Estradiol rapidly attenuated the astrocyte-evoked glutamate-mediated [Ca2+]i rise and slow inward current in neurons. Also, the incidence of astrocyte-induced increase in spontaneous postsynaptic current frequency was reduced in the presence of estradiol. The effects of estradiol were stereo-specific and reversible following washout. These findings may indicate that the regulation of neuronal excitability and synaptic transmission by astrocytes is sensitive to rapid estradiol-mediated hormonal control.

  2. Rapid vascular escape of arterially injected 16alpha-radioiodo, 17beta-estradiol

    SciTech Connect

    Scharl, A.; Holt, J.A. )

    1993-03-20

    The authors undertook this study because confirmation of a rapid vascular escape and slow release back into the circulatory system suggests that arterial injection of radiohalogenated steroid receptor ligands might provide an efficacious route of administration for imaging or treatment of receptor-rich malignant tumors in peripheral tissues. The authors injected radiolabeled 16alpha-iodo, 17beta-estradiol ([I]-E) into the femoral artery of swine in a solution that contained [[sup 125]I]-E in a known ratio to [[sup 99]Tc]-labeled red blood cells. Fractions of femoral venous blood were collected at short intervals during 10 min. They looked for changes in the ratio of the radiolabeles. [[sup 99m]Tc]-labeled red blood cells are known to remain in the vascular system for an hour or more. After passage of the injectate through the capillary bed of the swine leg, a dramatic decrease of the initial [sup 125]I:[sup 99m]Tc ratio to only 10% was observed in the femoral venous blood. This ratio increased gradually during the next 10 min to approximately 30% of that in the injectate, indicating that a significant portion (approximately 90%) of the [[sup 125]I]-E was initially trapped in the limb and then slowly re-entered the vascular system. To obtain visual confirmation of the rapid vascular escape of iodo-estrogen, they injected either an imageable form of [I]-E ([[sup 123]I]-E) or [[sup 99m]Tc]-labeled red blood cells into the dorsal aorta of superovulated rabbits, whose smaller size allowed whole-body imaging. The biodistributions of these radiopharmaceuticals were surveyed continuously by real-time planar gamma imaging. A large fraction of [I]-E escapes from the vascular system during the first pass through an organ or limb, without regard to the estrogen receptor content of the tissue. 28 refs., 3 figs., 1 tab.

  3. Effects of 17beta-estradiol on survival, growth, sexual development and molting cycles of the marine crustacean mysid shrimp, Americamysis bahia.

    PubMed

    Hirano, Masashi; Ishibashi, Hiroshi; Watanabe, Naoko; Matsumura, Naomi; Watanabe, Akiko; Onikura, Norio; Kishi, Katsuyuki; Shiratsuchi, Hideki; Arizono, Koji

    2004-01-01

    A 14-day partial life-cycle test was performed to assess the effects of 17beta-estradiol (E2) on the survival, growth, sexual development and molting cycles of a marine crustacean mysid shrimp (Americamysis bahia). Seven-day-old mysids were exposed to the nominal E2 concentrations of 31.3, 62.5, 125, 250 and 500 microg/l for 14 days. The total length and the body weight of mysids significantly decreased relative to the controls when exposed to 62.5, 250 and 500 microg/l E2 for 14 days. Moreover, the carapace length significantly decreased in the 500 microg/l E2 treatment groups. No significant differences were observed in sex ratio with the appearance of secondary sex characteristics in the all treatment groups including the control and solvent control groups. However, the percentage of females with eggs in the oviduct or brood sac decreased significantly in mysids treated with E2 at 62.5, 125, 250 and 500 microg/l. The cumulative total number of molting cycles when exposed to E2 for 14 days significantly decreased in the treatment groups at 500 microg/l relative to the controls. These results suggest that concentrations of E2 over 62.5 microg/l may cause growth suppression in mysid shrimp, and that the disruption of molting cycles may result in alterations in growth due to a sublethal response to toxicant exposure.

  4. Degradation of 17beta-estradiol in aqueous solution by ozonation in the presence of manganese(II) and oxalic acid.

    PubMed

    Jiang, Liying; Zhang, Lu; Chen, Jianmeng; Ji, Hong

    2013-01-01

    Natural estrogens, such as 17beta-estradiol (E2), are the main substances responsible for estrogenic activity found in domestic sewage. In the work described herein, the degradation of E2 has been investigated by single ozonation and catalytic ozonation in the presence of manganese ion (Mn2+) and oxalic acid. The presence of Mn2+ and oxalic acid in the ozonation processes significantly improved the E2 degradation and, hence, the reduction of estrogenic activity in aqueous solution. The addition of Mn2+ and oxalic acid produced many more hydroxyl radicals in the catalytic ozonation system than in the single ozonation system. Oxidation products formed during ozonation of E2 have been identified by means of gas chromatography-mass spectrometry (GC-MS), on the basis of which a possible reaction pathway for E2 degradation by ozonation is proposed. E2 was first oxidized to hydroxyl-semiquinone isomers, and these were subsequently degraded to low molecular weight compounds such as oxalic acid and malonic acid. The latter were easily oxidized by ozone to form carbon dioxide (CO2). The results demonstrate that the ozonation-Mn(2+)-oxalic acid system may serve as a powerful tool for removing E2, and the addition of Mn2+ and oxalic acid is favourable for the complete removal of estrogenic activity induced by steroid estrogens in aqueous solution.

  5. 17beta-Estradiol potentiates field excitatory postsynaptic potentials within each subfield of the hippocampus with greatest potentiation of the associational/commissural afferents of CA3.

    PubMed

    Kim, M T; Soussou, W; Gholmieh, G; Ahuja, A; Tanguay, A; Berger, T W; Brinton, R D

    2006-08-11

    We sought to determine the impact of 17beta-estradiol throughout the hippocampal trisynaptic pathway and to investigate the afferent fiber systems within CA1 and CA3 in detail. To achieve this objective, we utilized multielectrode arrays to simultaneously record the field excitatory postsynaptic potentials from the CA1, dentate gyrus, and CA3 of rat hippocampal slices in the presence or absence of 100 pM 17beta-estradiol. We confirmed our earlier findings in CA1, where 17beta-estradiol significantly increased field excitatory postsynaptic potentials amplitude (20%+/-3%) and slope (22%+/-7%). 17beta-Estradiol significantly potentiated the field excitatory postsynaptic potentials in dentate gyrus, amplitude (15%+/-4%) and slope (17%+/-5), and in CA3, amplitude (15%+/-4%) and slope (19%+/-5%). Using a high-density multielectrode array, we sought to determine the source of potentiation in CA1 and CA3 by determining the impact of 17beta-estradiol on the apical afferents and the basal afferents within CA1 and on the mossy fibers and the associational/commissural fibers within CA3. In CA1, 17beta-estradiol induced a modest increase in the amplitude (7%+/-2%) and slope (9%+/-3%) following apical stimulation with similar magnitude of increase following basal stimulation amplitude (10%+/-2%) and slope (12%+/-3%). In CA3, 17beta-estradiol augmented the mossy fiber amplitude (15%+/-3%) and slope (18%+/-6%) and the associational/commissural fiber amplitude (31%+/-13%) and slope (40%+/-15%). These results indicate that 17beta-estradiol potentiated synaptic transmission in each subfield of the hippocampal slice, with the greatest magnitude of potentiation at the associational/commissural fibers in CA3. 17beta-Estradiol regulation of CA3 responses provides a novel site of 17beta-estradiol action that corresponds to the density of estrogen receptors within the hippocampus. The implications of 17beta-estradiol potentiation of the field potential in each of the hippocampal subfields

  6. 17beta-estradiol promotes the synthesis and the secretion of annexin I in the CCRF-CEM human cell line.

    PubMed Central

    Castro-Caldas, M; Duarte, C B; Carvalho, A R; Lopes, M C

    2001-01-01

    AIMS: Annexin I (ANXA1), a 37kDa member of the annexin family of Ca2+-binding and phospholipid-binding proteins, is particularly abundant in various populations of peripheral blood leukocytes. Since this protein modulates the anti-inflammatory actions of the steroid hormones, the purpose of this study was to investigate the effects of the female sex steroid hormone, 17beta-estradiol (E2beta), on the synthesis and secretion of ANXA1 in the human CCRF-CEM acute lymphoblastic leukemia cell line. METHODS: Complementary reverse transcription-polymerase chain reaction and Western blot assays were performed to study the effect of E2beta on the expression of mRNA and protein ANXA1, respectively. RESULTS AND DISCUSSION: Treatment of CCRF-CEM cells with E2beta, for 30 min, stimulated the synthesis of ANXA1 mRNA molecules, and increased the cellular level of ANXA1 protein. Moreover, when the cells were incubated with E2beta under the same experimental conditions, a significant increase in the amount of ANXA1 secreted from the cells was also detected. ICI 182,780, a selective inhibitor of the intracellular estrogen receptor, had no effect on the E2beta-stimulated expression and externalisation of ANXA1. Taken together, these results indicate that E2beta induces de novo synthesis of ANXA1 and stimulates its secretion in the CCRF-CEM cell line, apparently through a mechanism independent of the intracellular estrogen receptor. PMID:11759108

  7. Effect of two oral doses of 17beta-estradiol associated with dydrogesterone on thrombin generation in healthy menopausal women: a randomized double-blind placebo-controlled study.

    PubMed

    Rousseau, Alexandra; Robert, Annie; Gerotziafas, Grigoris; Torchin, Dahlia; Zannad, Faiez; Lacut, Karine; Libersa, Christian; Dasque, Eric; Démolis, Jean-Louis; Elalamy, Ismail; Simon, Tabassome

    2010-04-01

    Oral hormone therapy is associated with an increased risk of venous thrombosis. Drug agencies recommend the use of the lowest efficient dose to treat menopausal symptoms for a better risk/ratio profile, although this profile has not been totally investigated yet. The aim of the study was to compare the effect of the standard dose of 17beta-estradiol to a lower one on thrombin generation (TG). In a 2-month study, healthy menopausal women were randomized to receive daily 1mg or 2 mg of 17beta-estradiol (E1, n = 24 and E2, n = 26; respectively) with 10 mg dydrogesterone or placebo (PL, n = 22). Plasma levels factors VII, X, VIII and II were assessed before and after treatment as well as Tissue factor triggered TG, which allows the investigation of the different phases of coagulation process. The peak of thrombin was higher in hormone therapy groups (E1: 42.39 +/- 50.23 nm, E2: 31.08 +/- 85.86 nm vs. 10.52 +/- 40.63 nm in PL, P = 0.002 and P = 0.01). Time to reach the peak was also shortened (PL: 0.26 +/- 0.69 min vs. E1: -0.26 +/- 0.80 min, E2: -0.55 +/- 0.79 min, P <10(-3) for both comparisons) and mean rate index of the propagation phase of TG was significantly increased. Among the studied clotting factors, only the levels of FVII were significantly increased after treatment administration. The two doses of 17beta-estradiol induced in a similar degree an acceleration of the initiation and propagation phase of tissue factor triggered thrombin generation and a significant increase of FVII coagulant activity.

  8. The use of specific radioimmunoassays to determine the renal clearance rates of estrone and 17 beta-estradiol during the menstrual cycle.

    PubMed

    Wright, K; Collins, D C; Preedy, J R

    1978-11-01

    Specific RIAs requiring ether extraction only were established for estrone and 17 beta-estradiol both in plasma and in urine from the nonpregnant female. These assays were used to measure the renal clearance rates of estrone and of 17 beta-estradiol in eight ambulatory women in the follicular and in the luteal phases of the menstrual cycle. The mean (+/-SE) for the renal clearance rate of estrone was 0.71 +/- 0.058 ml/min in the follicular phase and 1.26 +/- 0.35 ml/min in the luteal phase. The mean (+/-SE) renal clearance rate of 17 beta-estradiol was 0.44 +/- 0.055 ml/min in the follicular phase and 0.29 +/- 0.043 ml/min in the luteal phase. There was no significant difference in the renal clearance rates of either estrone or of 17 beta-estradiol between the follicular and luteal phases of the cycle. The renal clearances of estrone and 17 beta-estradiol were highly correlated (r = 0.84; P less than 0.01). The renal clearance rate of estrone was significantly greater than that of 17 beta-estradiol in both phases of the cycle (P less than 0.01).

  9. Transformation of oxidation products and reduction of estrogenic activity of 17beta-estradiol by a heterogeneous photo-Fenton reaction.

    PubMed

    Zhao, Yaping; Hu, Iangyong; Jin, Wei

    2008-07-15

    A novel photo-Fenton catalyst, alpha-FeOOH loaded resin (alpha-FeOO HR), was synthesized and evaluated through transformation of a steroidal endocrine disrupting compounds (EDC), 17beta-estradiol (E2), under weak UV irradiation in the presence of H2O2. E2 photodegradation intermediates elucidated in detail by GC/MS and LC/MS/MS analyses and detailed reaction pathways are proposed. A yeast-based estrogen screen for E2 and its photodegradation intermediates was performed to measure the reduction of estrogenic activity in different water matrices during the heterogeneous photo-Fenton process. The results showed that alpha-FeOOHR not only degraded E2 but also removed the estrogenic activity originating from E2, its degradation intermediates, and its products. However, the water matrix present in drinking water may impactestrogenic activity reduction. The results are important to evaluate the ability of photo-Fenton advanced oxidation processes in reducing EDCs and their associated estrogenicity from drinking water.

  10. 17 beta-estradiol induces spermatogonial proliferation through mitogen-activated protein kinase (extracellular signal-regulated kinase 1/2) activity in the lizard (Podarcis s. sicula).

    PubMed

    Chieffi, Paolo; Colucci D'Amato, Luca; Guarino, Fabio; Salvatore, Gaetano; Angelini, Francesco

    2002-02-01

    There are always more evidences indicating that 17beta-estradiol (E(2)) is necessary for normal male fertility. We have used a nonmammalian vertebrate model (the lizard Podarcis s. sicula) to investigate the regulation of extracellular signal-regulated kinase 1 and 2 (ERK1/2) activity in the testis during the annual sexual cycle and to study whether E(2) exerts a role in the spermatogenesis through ERK1/2 activity. Immunocytochemistry analysis shows that ERK1/2 proteins are present in the nucleus of the spermatogonia (SPG), and in primary (I) spermatocytes (SPC). The annual E(2) profile shows a progressive increase during the active spermatogenesis (from April to June) and a peak in the month of August (spermatogonial mitosis). In parallel, ERK1/2 (molecular weight 44 and 42 kDa, respectively) are highly phosphorylated during the period of active spermatogenesis and in post-refractory period (August) compared with the winter stasis (from November to March). Present results demonstrate that E(2) treatment induces spermatogonial proliferation, possibly via the activation of ERK1/2, and this effect is counteracted by the antiestrogen ICI 182-780.

  11. Gender-related effects of 17-{beta}-estradiol and B-hexachlorocyclohexane on liver tumor formation in medaka (Oryzias latipes)

    SciTech Connect

    Cooke, J.B.; Hinton, D.E.

    1994-12-31

    When medaka were acutely exposed to diethylnitrosamine (DEN), greater incidence of hepatocarcinoma was seen in female versus male fish. This is possibly related to elevated female endogenous estrogens, which increase liver weight and production of vitellogenin. To examine roles of estrogens in tumor modulation, 21-day old medaka were exposed to DEN (200 ppm for 24 hr.), then fed purified diets containing the estrogenic compound {beta}-hexachlorocyclohexane ({beta}-HCH) or 17-{beta}estradiol (E2) for 6 months. Incidences of basophilic preneoplastic foci of cellular alteration in females receiving DEN and 0.01, 0.1, or 1.0 ppm E2 were three times the incidences in similarly-treated males. Also, incidences of basophilic foci in DEN + 0.1 ppm E2 males were significantly increased over DEN-only males and were equal to incidences in DEN-only females. Liver weights and hepatosomatic indices of males given 0.1 ppm E2 were not significantly different than females fed control diet. Females fed 0.01-10.0 ppm {beta}-HCH after DEN had 4--5 times greater incidences of basophilic foci as males. Gender-related effects on kinetics of growth rates and volumes of foci are being examined.

  12. Gender determination in the Paiche or Pirarucu (Arapaima gigas) using plasma vitellogenin, 17beta-estradiol, and 11-ketotestosterone levels.

    PubMed

    Chu-Koo, F; Dugué, R; Alván Aguilar, M; Casanova Daza, A; Alcántara Bocanegra, F; Chávez Veintemilla, C; Duponchelle, F; Renno, J-F; Tello, Salvador; Nuñez, J

    2009-03-01

    Arapaima gigas is an air-breathing giant fish of Amazonian rivers. Given its great economic and cultural importance, the aquaculture development of this species represents an evident solution to face the decline of wild populations. In captivity, reproduction occurs generally in large earthen ponds where stocks of a few tens of brooders are maintained together at the beginning of the rainy season (December-March in the Peruvian Amazon). Fry production relies on the spontaneous formation of male and female pairs, which build a nest, delimit a territory and guard the offspring for at least 20 days from other congeners and predators. However, as sex determination of A. gigas is not possible by morphological criteria, it is very difficult to optimize reproduction conditions and fry production in each pond, which seriously hampers the culture of this species. This situation prompted us to develop sexing methodologies based on (1) the detection of female specific plasma Vitellogenin (Vtg) using an enzyme immuno assay (EIA), and (2) the determination of plasma 17beta-estradiol and 11-ketotestosterone levels for immature specimens. The Vtg purification was performed by electro-elution after polyacrilamide gel electrophoresis (PAGE) from plasma of 17beta-estradiol treated A. gigas juveniles. Two different Vtg molecules were isolated, (Vtg(1) and Vtg(2)) with 184 and 112 kDa apparent molecular masses, respectively, and two antibodies were raised in rabbits for each Vtg molecule. Adult fish were 100% accurately sexed by Vtg EIA, while 100% of immature fish and 95% of adults were accurately sexed by 17beta-Estradiol and 11-Ketestosterone ratios. We also observed different color pattern development in male and female adult fish (6-year-olds) around the reproductive period.

  13. HPLC-fluorescence detection and adsorption of bisphenol A, 17beta-estradiol, and 17alpha-ethynyl estradiol on powdered activated carbon.

    PubMed

    Yoon, Yeomin; Westerhoff, Paul; Snyder, Shane A; Esparza, Mario

    2003-08-01

    The adsorption of three estrogenic compounds (bisphenol A (BPA), 17beta-estradiol (E2), and 17alpha-ethynyl estradiol (EE2)) on several powdered activated carbons (PAC) was investigated. Without preconcentration, method detection limits (MDL) using high-performance liquid chromatography (HPLC) with fluorescence detection at an excitation wavelength of 280 nm and an emission wavelength of 310 nm were 0.88, 1.15, and 0.96 nM for BPA, E2, and EE2, respectively. Compound recoveries were >90% in raw drinking water matrices. PAC screening studies (six PAC brands) indicated all three compounds were removed by PAC, but the percentage removal ranged from 31% to >99% based upon PAC type/dosage and presence/absence of natural organic matter. The order of removal (E2>EE2>BPA) corresponded with logK(ow) values for the compounds (3.1-4.0, 3.7-3.9, 3.3, respectively). Kinetic and PAC dose-response experiments were conducted with the two best performing PACs. Increasing contact time and PAC dose improved compound removal. Freundlich isotherm parameters were fit to the experimental data. This study confirms that PAC treatment is feasible for >99% removal of three estrogenic compounds from raw drinking waters that may be at risk for containing such compounds, at least at initial concentration of 500 ng/l and higher.

  14. [Levels of progesterone, 17 beta-estradiol and 11-hydroxycorticosteroid in the blood in cows in different types of puerperal conditions].

    PubMed

    Zralý, Z; Kaláb, P; Canderle, J; Kummer, V; Raszyk, J

    1989-09-01

    Changes in progesterone (P4), 17 beta-estradiol (E2) and 11-hydroxycorticosteroid (11-OHCS) concentrations in blood plasma were determined in daily intervals from the day of parturition to day 15 post partum (p.p.) in cows with physiological puerperium (n = 8), with puerperal endometritis (n = 6), and with placenta retention (n = 6). Cows with puerperium disorders (endometritis, placenta retention) had significantly higher P4 levels in the period from day 3 to day 7 p.p. than cows with physiological puerperium. E2 concentrations decreased to basal values following the parturition in cows with spontaneous parturitions and subsequent expulsion of the placenta. A delayed decrease in E2 concentrations after parturition and a significant increase on day 5 and day 7 p.p. were recorded in the group of animals with placenta retention. Significantly higher levels of 11-OHCS in blood plasma were detected by day 5 or by day 8 p.p. in cows with placenta retention and puerperal endometritis. Extraovarial sources of sexual steroids resulting in endocrine malfunctions are discussed as well as likely consequences for puerperium.

  15. STEAP1 is over-expressed in breast cancer and down-regulated by 17beta-estradiol in MCF-7 cells and in the rat mammary gland.

    PubMed

    Maia, Cláudio J B; Socorro, Sílvia; Schmitt, Fernando; Santos, Cecília R A

    2008-01-01

    Six transmembrane epithelial antigen of the prostate 1 (STEAP1) was identified as a prostate-specific cell-surface antigen over-expressed in prostate cancer, and in human cancer cell lines obtained from several other tissues. Its cell surface location in all tumor types analyzed so far, and its absence in most vital organs in humans, turned STEAP1 into a potential target for anti-tumor immunotherapy. This study provides experimental evidence that STEAP1 is also over-expressed in human breast cancer cases, and in normal breast tissue adjacent to breast tumors, where it is localized in the cell membrane of epithelial cells. It is also demonstrated that STEAP1 transcription correlates negatively with estrogen receptor (ER) immunoreactivity, and positively with tumor grading in breast cancer cases. As estrogens are involved in breast cancer onset and progression, the response of STEAP1 to 17beta-estradiol (E2) was investigated in the mammary gland of rats, and in the human breast cancer cell line, MCF-7. These experiments demonstrated that STEAP1 is down-regulated by E2 in both models. The mechanisms underlying the STEAP1 response to E2 in vitro were further investigated in MCF-7 cells, and the results obtained suggest an effect mediated by the membrane-bound ERalpha (mbERalpha).

  16. Time- and Dose-Dependent Effects of 17 Beta-Estradiol on Short-Term, Real-Time Proliferation and Gene Expression in Porcine Granulosa Cells

    PubMed Central

    Ciesiółka, Sylwia; Budna, Joanna; Jopek, Karol; Bryja, Artur; Kranc, Wiesława; Borys, Sylwia; Jeseta, Michal; Chachuła, Adrian; Ziółkowska, Agnieszka; Antosik, Paweł; Bukowska, Dorota; Brüssow, Klaus P.; Bruska, Małgorzata; Nowicki, Michał

    2017-01-01

    The key mechanisms responsible for achievement of full reproductive and developmental capability in mammals are the differentiation and transformation of granulosa cells (GCs) during folliculogenesis, oogenesis, and oocyte maturation. Although the role of 17 beta-estradiol (E2) in ovarian activity is widely known, its effect on proliferative capacity, gap junction connection (GJC) formation, and GCs-luteal cells transformation requires further research. Therefore, the goal of this study was to assess the real-time proliferative activity of porcine GCs in vitro in relation to connexin (Cx), luteinizing hormone receptor (LHR), follicle stimulating hormone receptor (FSHR), and aromatase (CYP19A1) expression during short-term (168 h) primary culture. The cultured GCs were exposed to acute (at 96 h of culture) and/or prolonged (between 0 and 168 h of culture) administration of 1.8 and 3.6 μM E2. The relative abundance of Cx36, Cx37, Cx40, Cx43, LHR, FSHR, and CYP19A1 mRNA was measured. We conclude that the proliferation capability of GCs in vitro is substantially associated with expression of Cxs, LHR, FSHR, and CYP19A1. Furthermore, the GC-luteal cell transformation in vitro may be significantly accompanied by the proliferative activity of GCs in pigs. PMID:28337462

  17. Characterization of a 7 day 17 beta-estradiol transdermal delivery system: pharmacokinetics in healthy postmenopausal women.

    PubMed

    Boyd, R A; Zegarac, E A; Eldon, M A; Sedman, A J; Forgue, S T

    1996-08-01

    To assess the delivery characteristics of a new 7 day 17 beta-estradiol transdermal delivery system (TDS), estradiol and estrone pharmacokinetics were evaluated following a single 7 d application of one TDS or two TDSs in 24 healthy, postmenopausal women in a nonblind, randomized, two-period crossover study. Serial blood samples and total urine output were collected before (baseline measurement of endogenous hormone) and during TDS application, and for 24 h (urine) or 72 h (blood) following TDS removal. Serum was assayed for estradiol and estrone by a validated radioimmunoassay (RIA) method. The combined amounts of estradiol and its conjugates, and estrone and its conjugates in urine were determined by validated RIA methods. Overall, one or two estradiol TDSs were well tolerated by healthy, postmenopausal female volunteers. Estradiol absorption from the TDS was characterized by a zero-order process and was dose proportional, resulting in average steady-state serum estradiol concentrations of 16 and 33 pg mL-1 above baseline during the 7 d application of one and two TDSs, respectively. Parallel but smaller increases in serum estrone concentrations were observed, resulting in an increase in the serum estradiol/estrone concentration ratio from approximately 0.2 at baseline to median values of 0.64 and 0.88 during application of one and two TDSs, respectively. The 7 day 17 beta-estradiol TDS delivered a nominal estradiol dose of 0.02 mg/24 h during the intended wear period.

  18. Age-dependent changes in fecal 17beta-estradiol and progesterone concentrations in female spider monkeys (Ateles geoffroyi).

    PubMed

    Hernández-López, L; Cerda-Molina, A L; Chavira-Ramírez, R; Mondragón-Ceballos, R

    2010-03-01

    The objective of this study was to investigate whether sex steroids decreased with age in female black-handed spider monkeys (Ateles geoffroyi). Fecal concentrations of 17beta-estradiol and progesterone (five samples/wk) and the number of ovulatory and anovulatory cycles were compared between adult (n=3) and aged females (n=2). All animals (regardless of age) had higher 17beta-estradiol concentrations during the fertile than the nonfertile phases. However, during the fertile phase, concentrations of this hormone were significantly higher in adult females. Conversely, progesterone concentrations varied normally throughout the menstrual cycle in both adult and aged animals, with no significant difference between age classes. Similarly, there was no significant effect of age on the number of ovulatory and anovulatory cycles. In conclusion, we inferred that the aged female spider monkeys did not reach menopause, instead they remained in a perimenopausal period characterized by changes in fecal concentrations of ovarian steroids and hypothalamus-hypophysis-ovary axis activity, as well as irregular menstrual flows, for prolonged intervals.

  19. 17beta-estradiol attenuates programmed cell death in cortical pericontusional zone following traumatic brain injury via upregulation of ERalpha and inhibition of caspase-3 activation.

    PubMed

    Li, Li-Zhuo; Bao, Yi-Jun; Zhao, Min

    2011-01-01

    Pericontusional zone (PCZ) of traumatic cerebral contusion is a target of pharmacological intervention. It is well studied that 17beta-estradiol has a protective role in ischemic brain injury, but its role in brain protection of traumatic brain damage deserves further investigation, especially in pericontusional zone. Here we show that 17beta-estradiol enhances the protein expression and mRNA induction of estrogen alpha receptor (ERalpha) and prevents from programmed cell death in cortical pericontusional zone. ERalpha specific antagonist blocks this protective effect of 17beta-estradiol. Caspase-3 activation occurs in cortical pericontusional zone of the oil-treated injured rat brain and its activation is inhibited by 17beta-estradiol treatment. Additionally, ERalpha specific antagonist reverses this inhibition. Pan-caspase inhibitor also protect cortical pericontusional zone from programmed cell death. Our present study indicates 17beta-estradiol protects from programmed cell death in cortical pericontusional zone via enhancement of ERalpha and decrease of caspase-3 activation.

  20. Effects of long-term diabetes and/or high-dose 17 beta-estradiol on bone formation, bone mineral density, and strength in ovariectomized rats.

    PubMed

    Verhaeghe, J; Oloumi, G; van Herck, E; van Bree, R; Dequeker, J; Einhorn, T A; Bouillon, R

    1997-05-01

    Long-term diabetes in female rats preserves the bone mineral density (BMD) but impairs the strength of the femur. In this study, we have compared the effects of diabetes and high-dose 17 beta-estradiol (E2), two conditions of low bone formation, in ovariectomized (ovx) rats. Spontaneously diabetic BB rats were ovx 0-3 days after onset, and nondiabetic ovx littermates were used as controls; the rats were either untreated or treated with E2 (30 micrograms/day, subcutaneously), for 6 or 12 weeks (n = 9 in each of the eight groups). Analysis included: plasma 1,25-dihydroxyvitamin D3, insulin-like growth factor-I (IGF-I), and osteocalcin concentrations; histomorphometry of the proximal tibial metaphysis (PTM); and DXA and biomechanical testing of the femur. Both E2 treatment and diabetes markedly lowered plasma IGF-I and osteocalcin concentrations, as well as dynamic morphometric parameters of bone formation in the PTM. Plasma IGF-I and osteocalcin were correlated (R2 = 0.55; p < 0.0001). E2 treatment in both control and diabetic ovx rats increased the trabecular bone volume in the PTM and the BMD in the metaphysis of the distal femur; there was no difference between control and diabetic rats, however. The diaphyseal area and BMC were decreased in E2-treated or/and diabetic ovx rats, but the diaphyseal BMD remained unchanged compared with untreated ovx rats. The biomechanical properties of the whole femur (strength, angular deformation, and stiffness) were decreased in E2-treated and diabetic E2-treated ovx rats after 12 weeks. The data indicate that in situations of chronic low bone formation, whole bone strength does not reflect total BMD but correlates better with bone size and bone mineral content measurements.

  1. The effects of steroidal estrogens in ACI rat mammary carcinogenesis: 17beta-estradiol, 2-hydroxyestradiol, 4-hydroxyestradiol, 16alpha-hydroxyestradiol, and 4-hydroxyestrone.

    PubMed

    Turan, V K; Sanchez, R I; Li, J J; Li, S A; Reuhl, K R; Thomas, P E; Conney, A H; Gallo, M A; Kauffman, F C; Mesia-Vela, S

    2004-10-01

    Several investigators have suggested that certain hydroxylated metabolites of 17beta-estradiol (E2) are the proximate carcinogens that induce mammary carcinomas in estrogen-sensitive rodent models. The studies reported here were designed to examine the carcinogenic potential of different levels of E2 and the effects of genotoxic metabolites of E2 in an in vivo model sensitive to E2-induced mammary cancer. The potential induction of mammary tumors was determined in female ACI rats subcutaneously implanted with cholesterol pellets containing E2 (1, 2, or 3 mg), or 2-hydroxyestradiol (2-OH E2), 4-hydroxyestradiol (4-OH E2), 16alpha-hydroxyestradiol (16alpha-OH E2), or 4-hydoxyestrone (4-OH E1) (equimolar to 2 mg E2). Treatment with 1, 2, or 3 mg E2 resulted in the first appearance of a mammary tumor between 12 and 17 weeks, and a 50% incidence of mammary tumors was observed at 36, 19, and 18 weeks respectively. The final cumulative mammary tumor incidence in rats treated with 1, 2, or 3 mg E2 for 36 weeks was 50%, 73%, and 100% respectively. Treatment of rats with pellets containing 2-OH E2, 4-OH E2, 16alpha-OH E2, or 4-OH E1 did not induce any detectable mammary tumors. The serum levels of E2 in rats treated with a 1 or 3 mg E2 pellet for 12 weeks was increased 2- to 6-fold above control values (approximately 30 pg/ml). Treatment of rats with E2 enhanced the hepatic microsomal metabolism of E2 to E1, but did not influence the 2- or 4-hydroxylation of E2). In summary, we observed a dose-dependent induction of mammary tumors in female ACI rats treated continuously with E2; however, under these conditions 2-OH E2, 4-OH E2, 16alpha-OH E2, and 4-OH E1 were inactive in inducing mammary tumors.

  2. Effects of oral continuous and transdermal cyclic 17-beta estradiol and norethindrone acetate replacement therapy on platelet aggregation in postmenopausal women.

    PubMed

    Kaplan, Petek Balkanli; Gücer, Fatih; Sayin, N Cenk; Yüce, M Ali; Yardim, Turgut

    2002-08-01

    To evaluate the effects of an oral continuous and transdermal cyclic 17-beta estradiol and norethindrone acetate combination on platelet aggregation in post-menopausal women. Fifty postmenopausal women were randomly assigned to receive 17-beta estradiol and norethindrone acetate either orally continuously or transdermally cyclically and sequentially. Platelet counts and maximum platelet aggregation rates were measured before and after three months treatment. At three months there were no significant changes in platelet counts or in adenosine diphosphate-induced or epinephrine-induced platelet aggregation rates in either treatment group. Hormone replacement treatment with a 17-beta estradiol and norethindrone acetate combination either orally continuously or transdermally cyclically and sequentially does not affect platelet aggregation in postmenopausal women.

  3. Modulation of 17{beta}-estradiol-induced responses in fish by cytochrome P4501A1 inducing compounds

    SciTech Connect

    Anderson, M.J.; Hinton, D.E.

    1995-12-31

    Some compounds which induce cytochrome P4501A1 (CYP1A1) are antiestrogenic in mammalian bioassay, and this effect is linked to aryl hydrocarbon (Ah) receptor. Liver of fish synthesizes estrogen-inducible egg yolk precursor protein vitellogenin (Vg) which is critical for oocyte maturation and ovarian development. To determine if Ah receptor-linked endocrine modulation could occur in fish liver, primary cultures of juvenile rainbow trout (Oncorhynchus mykiss) liver cells were co-administered 17{beta}-estradiol and CYP1A1 inducing compounds. Vitellogenin and albumin, estimated by ELISA measurement of concentration in the media 48 hrs after treatment, formed the basis for the test. Cellular CYP1A1 protein content and catalytic activity was estimated by ELISA and ethoxyresorufin-O-deethylase (EROD) activity assays respectively. Equivalent viability (mitochondrial dehydrogenase activity) and secretary functional capacity (albumin synthesis) were estimated and correlated with other results. In descending order, 2,3,4,7,8 pentachlorodibenzofuran (10{sup {minus}12} to 10{sup {minus}8} M) > 2,3,7,8 tetrachlorodibenzo-p-dioxin {approx_equal} 2,3,7,8 tetrachlorodibenzofuran (10{sup {minus}11} to 10{sup {minus}8} M) > {beta}-naphthoflavone (10{sup {minus}7} to 10{sup {minus}6} M) inhibited Vg synthesis in 17{beta}-estradiol treated liver cells. Potency of inhibition directly related to strength as an inducer of CYP1A1 protein. At 10-8 M, PCB congeners 77, 126, and 156 did not inhibit Vg synthesis and induced no or only moderate CYP1A1 protein. At 10-8 M, PCB congener 114, a weak CYP1A1 inducer, potentiated Vg synthesis relative to cells treated with 17{beta}-estradiol alone. This study increases their understanding of the consequences of hepatic CYP1A1 induction, forewarns of reproductive impairment of sexually maturing fishes exposed to CYP1A1 inducing compounds and argues for further, more detailed in vivo investigation.

  4. The role of beta 2-adrenergic vascular receptors in the peripheral vasodilation caused by 17 beta-estradiol in anesthetized pigs.

    PubMed

    Molinari, C; Battaglia, A; Grossini, E; Mary, D A; Surico, N; Vacca, G

    1999-01-01

    It has been previously shown in anesthetized pigs that intravenous infusion of 2 microg/h of 17beta-estradiol primarily dilated renal, iliac and coronary circulations, while higher doses of the hormone were required to cause vasodilation also in the mesenteric vascular bed. In the same experimental model, a tonic beta2-adrenoceptor mediated vasodilation, which could be argued to attenuate the vasodilator effect of 17beta-estradiol, has been described. The present study was planned to investigate the role of beta2-adrenergic receptors in the hemodynamic responses of renal and mesenteric vascular beds to 17beta-estradiol. Changes in flow caused by intravenous infusion of 2 microg/h of the hormone at constant heart rate and aortic blood pressure in the left renal and superior mesenteric arteries were assessed using electromagnetic flowmeters. In six pigs, infusion of 17beta-estradiol caused an increase in renal blood flow, which averaged 12.1% of the control values, without affecting mesenteric blood flow. In the same pigs, after hemodynamic variables had returned to the baseline values, blockade of beta2-adrenergic receptors with butoxamine caused an increase in aortic blood pressure and an increase in renal and mesenteric resistance. The subsequent infusion of 17beta-estradiol elicited increases in renal and mesenteric blood flow which respectively averaged 19.6% and 12.8%. Therefore, the present study in anesthetized pigs have shown that the vasodilator responses of the renal and mesenteric circulations to 17beta-estradiol were attenuated and even masked by a tonic beta2-adrenoceptor mediated vasodilation. This indicates that some vasodilator effects elicited by normally used replacement doses of the hormone may not be apparent.

  5. Changes in hypothalamic monoamine oxidase activity in relation to season, ovariectomy, and 17 beta-estradiol administration in intact and ovariectomized catfish, Clarias batrachus (L.).

    PubMed

    Manickam, P; Joy, K P

    1989-09-01

    Cyclic changes in hypothalamic monoamine oxidase (MAO) activity were noted during the annual ovarian cycle of Clarias batrachus, with a high level in the preparatory phase and a low level in the spawning phase. Administration of 17 beta-estradiol (E2) daily for 3 days induced both season- and dose-dependent responses in enzyme activity. In the preparatory phase, 0.05, 0.1, and 0.5 microgram/g doses of E2 enhanced enzyme activity in a dose-dependent manner, with significant changes being observed in the latter two dose groups. Administration of 1.0 and 10.0 micrograms/g doses decreased enzyme activity, with a significant difference elicited by the latter dose. In the spawning phase, enzyme activity was significantly elevated by 0.05 and 0.1 microgram/g doses. MAO activity decreased insignificantly in the 0.5 and 1.0 microgram/g groups and significantly in the 10.0 micrograms/g E2 group. Enzyme activity decreased significantly 2, 3, and 4 weeks after ovariectomy (prespawning phase), in a time-dependent manner, and increased after 5 weeks (not significantly different from the sham control value) and 6 weeks. Administration of E2 to 3-week ovariectomized fish elicited dose-dependent effects on MAO activity. E2 injections at 0.05 and 0.1 microgram/g doses not only restored the ovariectomy-induced decrease, but also elevated enzyme activity significantly compared with the sham + vehicle control. The higher doses (0.5 and 1.0 microgram/g) were ineffective in restoring enzyme activity, which decreased significantly in the 1.0 microgram/g group compared with ovariectomy and sham control values.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. 17Beta-estradiol reduces nitrotyrosine immunoreactivity and increases SOD1 and SOD2 immunoreactivity in nigral neurons in male mice following MPTP insult.

    PubMed

    Tripanichkul, Wanida; Sripanichkulchai, Kittisak; Duce, James A; Finkelstein, David I

    2007-08-20

    Emerging evidence suggests the beneficial effects of estrogen on Parkinson's disease (PD), yet the mechanisms of action implicated remain elusive. While experimental evidence suggests that estrogen possesses potent antioxidative properties, it is still unknown whether the hormone exhibits a neuroprotection in a PD animal model through its antioxidant activities. This study therefore investigated the effects of 17beta-estradiol (E2) on the immunoreactivity of nigral neurons and glia for nitrotyrosine (NT, a stable marker for oxidative stress), Cu/Zn superoxide dismutase (SOD1) and Mn superoxide dismutase (SOD2) in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model. Adult male mice were treated with E2 or vehicle for 11 days during which they were injected with MPTP or saline on the sixth day. The brains were collected on day 11 and quantitative immunohistochemistry was used to assess the number of NT-, SOD1- and SOD2-immunoreactive (IR) cells in the substantia nigra pars compacta (SNpc). In saline-treated group, E2 decreased NT-IR neuronal number and raised SOD1 and SOD2 expression in neurons and glia in the SNpc. MPTP induced a significant increase in the number of NT- and SOD2-IR neurons, but decreased the number of SOD1-IR neurons. MPTP also triggered a significant increase of SOD2- and SOD1-IR glial number. E2 pretreatment in MPTP mice reduced the number of NT-IR neurons, increased the number of SOD1- and SOD2-IR neurons, but did not alter the MPTP effect on glia immunoreactive to either SOD. Stimulation of SOD1 and SOD2 expression in nigral neurons suggests that E2 provides neuroprotection against MPTP-induced oxidative stress, partly through its ability to act as an antioxidant.

  7. Transcriptional activation of insulin-like growth factor binding protein 6 by 17beta-estradiol in SaOS-2 cells.

    PubMed

    Zhao, Yu-yan; Guo, Lei; Zhao, Xiao-juan; Liu, Hong; Lei, Tian; Ma, Dong-jie; Gao, Xiao-yu

    2009-07-31

    Osteoblasts can synthesize the insulin-like growth factors (IGFs) and the IGF-binding proteins (IGFBPs), which may either enhance or attenuate IGF-stimulated bone cell proliferation. Since estrogen induced osteoblastic differentiation and proliferation through an estrogen-responsive gene in target cells, we investigated the effects of estrogen on IGFBP-6 expression in the human osteoblastic-like cell line SaOS-2. Expressions of IGFBP-6 protein and mRNA increased 2.8 and 2-fold, respectively, in the presence of 17-beta-estradiol (E2) (0.01 to 1 micronM) and estrogen receptor (ER) in SaOS-2 cells. On the other hand, E2 induced a 2-fold increase in SaOS-2 cell proliferation. To identify genomic sequences associated with estrogen responsiveness, the 5'-promoter region (-44 to +118) of the IGFBP-6 gene was cloned into a chloramphenicol acetyltransferase (CAT) reporter vector. E2 induced a 3-fold increase in CAT activity in SaOS-2 cells transiently transfected with this construct. Identification of the estrogen-responsive element (ERE) [5-CCTTCA CCTG-3] (-9 to +1) in this IGFBP-6 gene promoter region was confirmed using electromobility shift assays and deletion analysis. This functional ERE was important for E2-induced trans-activation of the IGFBP-6 gene. These results demonstrate that E2 exhibits a positive effect on IGFBP-6 gene transcription through estrogen-liganded ER binding to the functional ERE in the IGFBP-6 gene promoter in SaOS-2 cells.

  8. HCG, progesterone and 17-beta-estradiol levels during extra-amniotically induced early abortion by a new prostaglandin derivative (Sulprostone).

    PubMed

    Nilsson, S; Zador, G; Nygren, K G; Wide, L

    1981-01-01

    A new prostaglandin E2 derivative (Sulprostone) was given extra-amniotically to 17 healthy women, who were 7-8 weeks pregnant, in order to assess the plasma profile of HCG, 17 beta-estradiol (E2), and progesterone and to evaluate the effectiveness and overall acceptability of the method in relation to different dose levels. On the lowest dose level (5 micrograms) only 3 of 7 patients aborted within a 3-to 6-day period. At higher dose levels (10 and 15 micrograms, respectively) 9 out of 10 women exhibited clinical evidence of an abortion. In the group who aborted, E2, progesterone, and HCG decreased continuously, whereas in the nonabortion group decreased levels were found 3 and 6 h after administration of the drug, but already after 24 h the values had again increased. Practically all treated women experienced lower abdominal discomfort, 7 (41%) reported the pains being severe. Vomiting and/or diarrhea occurred in 4 patients (24%). Similarly to other hitherto tested prostaglandins in humans, this new analogue exhibits its effect primarily through direct stimulatory effect on the uterine smooth muscle, resulting in subsequent decline in the concentrations of HCG, E2, and progesterone. In the group of successful inductions the decrease of the HCG concentration was close the half-time of HCG, indicating a permanent damage to the placenta. Despite the high success rate at a dose of 10 micrograms or more, the side effects, mainly abdominal cramps. were too severe to make this method feasible for the induction of early abortion when comparing to the available routine procedure of rapid vacuum curettage used on an outpatients basis.

  9. The effect of 17beta-estradiol on IL-6 secretion and NF-kappaB DNA-binding activity in human retinal pigment epithelial cells.

    PubMed

    Paimela, Tuomas; Ryhänen, Tuomas; Mannermaa, Eliisa; Ojala, Johanna; Kalesnykas, Giedrius; Salminen, Antero; Kaarniranta, Kai

    2007-06-15

    Toll-like receptors (TLRs) and inflammatory cascades participate in the pathology of age-related macular degeneration (AMD). The effect of estrogens on the development of AMD is poorly understood, although many studies indicate that these compounds can modulate inflammatory responses. In this study, we investigated the regulatory role of TLR agonists and 17beta-estradiol (E(2)) on IL-6 expression and NF-kappaB DNA-binding activity in human retinal pigment epithelial cells (ARPE-19). The inflammatory response of ARPE-19 cells to various TLR agonists, e.g. Pam, zymosan, flagellin, SLTA and lipopolysaccharide (LPS) exposures were examined via the secretion of IL-6 cytokine as analyzed by ELISA. In addition, the IL-6 responses to the estrogen-receptor agonist, E(2), and to the estrogen-receptor antagonist ICI 182.780 as well as to the NF-kappaB inhibitor helenalin were compared. The DNA-binding activity of NF-kappaB transcription factor of nuclear cell extracts was analyzed by the gel mobility shift assay (EMSA). TLR4 gene expression was studied by quantitave PCR. The TLR4 agonist, LPS, caused a clear IL-6 response that was attenuated by E(2) in ARPE-19-cells. The anti-inflammatory properties of E(2) were mediated through estrogen receptors and were associated with decreased NF-kappaB DNA-binding activity. The level of TLR4 gene expression was not affected by LPS exposure. Our results indicate that IL-6 expression is regulated through NF-kappaB transcription factor and stereoid-receptor signalling pathways in ARPE-19 cells.

  10. 17 beta-estradiol modifies nitric oxide-sensitive guanylyl cyclase expression and down-regulates its activity in rat anterior pituitary gland.

    PubMed

    Cabilla, Jimena P; Díaz, María del Carmen; Machiavelli, Leticia I; Poliandri, Ariel H; Quinteros, Fernanda A; Lasaga, Mercedes; Duvilanski, Beatriz H

    2006-09-01

    Previous studies showed that 17 beta-estradiol (17 beta-E2) regulates the nitric oxide (NO)/soluble guanylyl cyclase (sGC)/cGMP pathway in many tissues. Evidence from our laboratory indicates that 17 beta-E2 disrupts the inhibitory effect of NO on prolactin release, decreasing sGC activity and affecting the cGMP pathway in anterior pituitary gland of adult ovariectomized and estrogenized rats. To ascertain the mechanisms by which 17 beta-E2 affects sGC activity, we investigated the in vivo and in vitro effects of 17 beta-E2 on sGC protein and mRNA expression in anterior pituitary gland from immature female rats. In the present work, we showed that 17 beta-E2 acute treatment exerted opposite effects on the two sGC subunits, increasing alpha1 and decreasing beta1 subunit protein and mRNA expression. This action on sGC protein expression was maximal 6-9 h after 17 beta-E2 administration. 17beta-E2 also caused the same effect on mRNA expression at earlier times. Concomitantly, 17 beta-E2 dramatically decreased sGC activity 6 and 9 h after injection. These effects were specific of 17 beta-E2, because they were not observed with the administration of other steroids such as progesterone and 17 alpha-estradiol. This inhibitory action of 17beta-E2 on sGC also required the activation of estrogen receptor (ER), because treatment with the pure ER antagonist ICI 182,780 completely blocked 17 beta-E2 action. 17 beta-E2 acute treatment caused the same effects on pituitary cells in culture. These results suggest that 17 beta-E2 exerts an acute inhibitory effect on sGC in anterior pituitary gland by down-regulating sGC beta 1 subunit and sGC activity in a specific, ER-dependent manner.

  11. Validating a commercially available enzyme immunoassay for the determination of 17beta-estradiol and progestogens in the feces of cheetahs (Acinonyx jubatus): a case report.

    PubMed

    Borque, C; Perez-Garnelo, S S; Lopez, M; Talavera, C; Delclaux, M; de la Fuente, J

    2005-03-01

    Fecal 17beta-estradiol and progestogens excretion was monitored in adult, female cheetahs (Acinonyx jubatus; n = 2), ZGG-12301 (born 3 April 1993), gonadotrophin treated and ZGT-3301, (born 19 August 1993), nontreated, for 120 days using commercially available plate enzyme immunoassay kits prepared for human serum or plasma. There were significant differences (P < 0.001) between baseline and peak concentrations of both hormone measures. Female ZGG-12301, which conceived, but this pregnancy resulted in an unobserved spontaneous abortion, showed no significant difference (P > 0.05) between baseline and gestation 17beta-estradiol values; fecal 17beta-estradiol excretion during pregnancy was statistically different (P < 0.001) from excretion during the nonpregnancy period. Baseline progestogen concentrations were different from pregnancy (P < 0.001) and postovulatory (P < 0.01) concentrations, and progestogen concentrations during pregnancy period were different (P < 0.001) from postovulatory concentrations. In the nontreated cheetah (ZGT-3301), basal and increased progestogen concentrations were statistically different (P < 0.01). On the basis of 17beta-estradiol excretory patterns, duration of the estrous cycle (x +/- SEM) was 13.2 +/- 2.2 days. These results suggest that the enzyme-linked immunosorbent methods reported in this study were capable of quantifying reproductive hormones in fecal extracts of cheetahs and could be a practical alternative to other enzyme-linked immunosorbent assays which require more complex procedures.

  12. Interplay of IGF-I and 17beta-estradiol at age-specific levels in human sebocytes and fibroblasts in vitro.

    PubMed

    Makrantonaki, Evgenia; Vogel, Kim; Fimmel, Sabine; Oeff, Marina; Seltmann, Holger; Zouboulis, Christos C

    2008-10-01

    In order to obtain greater insights into the molecular mechanisms accompanying hormonal aging the effects of growth hormone (GH), insulin-like growth factor-I (IGF-I), 17beta-estradiol, progesterone and dehydroepiandrosterone were tested as single agents in concentrations corresponding to 20- and 60-year-old females on human SZ95 sebocytes and fibroblasts. Cell proliferation and viability were measured by 4-methylumbelliferyl heptanoate and lactate dehydrogenase microassays, respectively, whereas lipid accumulation was documented via nile red microassay and fluorescence microscopy. mRNA and protein expression were evaluated via real-time RT-PCR and Western blotting or ELISA, accordingly. Our results depict the importance of IGF-I for lipid synthesis in SZ95 sebocyte and demonstrate the lack of 17beta-estradiol, dehydroepiandrosterone and progesterone activity on lipid synthesis and SZ95 sebocyte proliferation suggesting that the action of these hormones in vivo may be implemented through indirect pathways. Fibroblast showed to be more susceptible to 17beta-estradiol treatment, while IGF-I could significantly stimulate fibroblast proliferation in a dose-dependent manner. Furthermore, an interplay between the 17beta-estradiol and IGF-I signaling pathway was documented in both cell types. In conclusion, IGF-I is a key regulator of human skin aging and declining IGF-I levels with age may play a significant role in the reduction of skin surface lipids and thickness.

  13. Bleeding patterns in postmenopausal women using continuous combination hormone replacement therapy with conjugated estrogen and medroxyprogesterone acetate or with 17beta-estradiol and norethindrone acetate.

    PubMed

    Odmark, I S; Jonsson, B; Bäckström, T

    2001-05-01

    We studied bleeding patterns in postmenopausal women who were using 2 types of continuous combination regimens. A prospective, double-blind, randomized study of 208 postmenopausal women treated with conjugated estrogen, 0.625 mg, and medroxyprogesterone acetate, 5 mg, or with 17beta-estradiol, 2 mg, and norethindrone acetate, 1 mg. The mean number of bleeding days decreased during the first 4 months of treatment (P <.002) but not thereafter. The number of bleeding days was fewer (P <.002) and the time until amenorrhea was shorter (P <.02) in patients receiving conjugated estrogen and medroxyprogesterone acetate than in patients receiving 17beta-estradiol and norethindrone acetate. The odds ratio for progression to amenorrhea with the use of conjugated estrogen and medroxyprogesterone acetate was 1.58, in comparison with the use of 17beta-estradiol and norethindrone acetate. A thick endometrium at the start of treatment resulted in more bleeding days than were found for a thin endometrium (P <.03). Body mass index, age, and blood pressure had no predictive value for bleeding problems. Treatment with continuous combined conjugated estrogen and medroxyprogesterone acetate resulted in fewer bleeding problems than did treatment with 17beta-estradiol and norethindrone acetate. Endometrial thickness may help to predict the chance of achieving amenorrhea during early hormone replacement therapy.

  14. 17beta-estradiol combined with testosterone promotes chicken osteoblast proliferation and differentiation by accelerating the cell cycle and inhibiting apoptosis in vitro.

    PubMed

    Chen, Xiuxia; Deng, Yifeng; Zhou, Zhenlei; Tao, Qingshu; Zhu, Jie; Li, Xiaolan; Chen, Jinli; Hou, Jiafa

    2010-02-01

    Medullary bone is a unique tissue in the long bones cavities of lay hens, and plays an important role as a calcium reservoir for egg-shell formation. Medullary bone formation requires the synergistic action of estrogen and androgen on osteoblasts during the early stage of sexual maturity. The objective of the current study was to investigate the effects of 17beta-estradiol, testosterone, and the combination on the proliferation, alkaline phosphatase (ALP) activity, apoptosis, the cell cycle of chicken osteoblasts in vitro. The proliferation of osteoblasts was examined with the MTT assay. Apoptosis and the cell cycle were assessed with flow cytometry. Either 17beta-estradiol (200 pg ml(-1)) or testosterone (100 pg ml(-1)) or the combination (100 pg ml(-1) each) significantly enhanced osteoblast proliferation and ALP activity, accelerated the osteoblast cell cycle, and stimulated osteoblast DNA synthesis in a period of 24 h. 17beta-estradiol, used alone or with testosterone, inhibited chicken osteoblast apoptosis; However, testosterone alone induced cell apoptosis. In conclusion, 17beta-estradiol combined with testosterone promoted osteoblast proliferation and ALP activity, accelerated the osteoblast cell cycle, inhibited osteoblast apoptosis.

  15. Beta-sitosterol and 17beta-estradiol alter gonadal steroidogenic acute regulatory protein (StAR) expression in goldfish, Carassius auratus.

    PubMed

    Sharpe, Rainie L; Woodhouse, Amanda; Moon, Thomas W; Trudeau, Vance L; MacLatchy, Deborah L

    2007-03-01

    Fish exposed to the phytosterol beta-sitosterol (beta-sit) have decreased circulating hormone and cholesterol concentrations, and decreased gonadal intra-mitochondrial cholesterol pools. The current study examined the potential for beta-sit to alter abundance of the key cholesterol transport protein, steroidogenic acute regulatory (StAR) protein, which delivers cholesterol to the first and rate-limiting steroidogenic enzyme P450 side chain cleavage (P450(scc)) inside the mitochondria. Plasma testosterone (T) and lipids (cholesterol, lipoproteins and triglycerides) were also measured. Goldfish were exposed to 200 microg/g beta-sit (97% pure or as a 72.6% pure phytosterol mixture) and 10 microg/g 17beta-estradiol (E(2); estrogenic control) by intra-peritoneal Silastic implants for 21-days or for five-months. Plasma T was significantly decreased in male fish exposed to the phytosterol mixture following the long-term exposure (p<0.001). There were no differences in total cholesterol concentrations among treatments in the short- or long-term exposure, but male fish in the long-term exposure had significantly lower HDL as compared to control fish (p<0.025) with a corresponding increase in LDL. StAR transcript levels were unchanged following the short-term exposure, but were reduced after five months in male beta-sit fish (p=0.05) and E(2)-treated female fish (p=0.05). This reduction in StAR transcript abundance in conjunction with decreased plasma T and altered plasma lipoprotein fractions demonstrates a non-estrogenic effect of beta-sit. This is the first study to show that beta-sit has the capacity to alter gonadal StAR transcript abundance, offering a mechanism by which beta-sit disrupts reproductive endocrine endpoints.

  16. Effects of the estrogen agonist 17beta-estradiol and antagonist tamoxifen in a partial life-cycle assay with zebrafish (Danio rerio).

    PubMed

    van der Ven, Leo T M; van den Brandhof, Evert-Jan; Vos, José H; Wester, Piet W

    2007-01-01

    A partial life-cycle assay (PLC) with zebrafish (Danio rerio) was conducted to identify endocrine-disrupting effects of 17beta-estradiol (E2) and tamoxifen (TMX) as reference for estrogen agonist and antagonist activity. Adult zebrafish were exposed for 21 d and offspring for another 42 d, allowing differentiation of gonads in control animals. The assessed end points included reproductive variables (egg production, fertilization, and hatching), gonad differentiation of juveniles, histopathology, and vitellogenin (VTG) expression. With E2, the most sensitive end points were feminization of offspring (at 0.1 nM) and increased VTG production in males (at 0.32 nM). At 1 nM, decreased F, survival, increased F, body length and weight, VTG-related edema and kidney lesions, and inhibited spermatogenesis were observed. Oocyte atresia occurred at even higher concentrations. Exposure to TMX resulted in specific effects at an intermediate test concentration (87 nM), including oocyte atresia with granulosa cell transformation and disturbed spermatogenesis (asynchrony within cysts). In F1, decreased hatching, survival, and body weight and length as well as decreased feminization were observed. Decreased vitellogenesis and egg production in females and clustering of Leydig cells in males occurred at higher concentrations. Toxicological profiles of estrogen agonists and antagonists are complex and specific; a valid and refined characterization of endocrine activity of field samples therefore can be obtained only by using a varied set of end points, including histology, as applied in the presented PLC. Evaluation of only a single end point can easily produce under- or overestimation of the actual hazard.

  17. Transport of 17beta-estradiol and testosterone in a field lysimeter

    USDA-ARS?s Scientific Manuscript database

    17ß-estradiol (E2) and testosterone (T) are present in sources such as waste treatment effluent and manures, and can potentially disrupt aquatic organisms at low concentrations. Laboratory studies consistently indicate limited mobility and rapid attenuation of E2 and T in soils; however, these hormo...

  18. Dose-dependent effects of 17-beta-estradiol on pituitary thyrotropin content and secretion in vitro.

    PubMed

    Moreira, R M; Lisboa, P C; Curty, F H; Pazos-Moura, C C

    1997-09-01

    We studied the basal and thyrotropin-releasing hormone (TRH) (50 nM) induced thyrotropin (TSH) release in isolated hemipituitaries of ovariectomized rats treated with near-physiological or high doses of 17-beta-estradiol benzoate (EB; sc, daily for 10 days) or with vehicle (untreated control rats, OVX). One group was sham-operated (normal control). The anterior pituitary glands were incubated in Krebs-Ringer bicarbonate medium, pH 7.4, at 37 degrees C in an atmosphere of 95% O2/5% CO2. Medium and pituitary TSH was measured by specific RIA (NIDDK-RP-3). Ovariectomy induced a decrease (P < 0.05) in basal TSH release (normal control = 44.1 +/- 7.2; OVX = 14.7 +/- 3.0 ng/ml) and tended to reduce TRH-stimulated TSH release (normal control = 33.0 +/- 8.1; OVX = 16.6 +/- 2.4 ng/ml). The lowest dose of EB (0.7 microgram/100 g body weight) did not reverse this alteration, but markedly increased the pituitary TSH content (0.6 +/- 0.06 microgram/hemipituitary; P < 0.05) above that of OVX (0.4 +/- 0.03 microgram/hemipituitary) and normal rats (0.46 +/- 0.03 microgram/hemipituitary). The intermediate EB dose (1.4 micrograms/100 g body weight) induced a nonsignificant tendency to a higher TSH response to TRH compared to OVX and a lower response compared to normal rats. Conversely, in the rats treated with the highest dose (14 micrograms/100 g body weight), serum 17-beta-estradiol was 17 times higher than normal, and the basal and TRH-stimulated TSH release, as well as the pituitary TSH content, was significantly (P < 0.05) reduced compared to normal rats and tended to be even lower than the values observed for the vehicle-treated OVX group, suggesting an inhibitory effect of hyperestrogenism. In conclusion, while reinforcing the concept of a positive physiological regulatory role of estradiol on the TSH response to TRH and on the pituitary stores of the hormone, the present results suggest an inhibitory effect of high levels of estrogen on these responses.

  19. 17beta-estradiol Attenuates TNF-α-Induced Premature Senescence of Nucleus Pulposus Cells through Regulating the ROS/NF-κB Pathway

    PubMed Central

    Li, Pei; Gan, Yibo; Xu, Yuan; Wang, Liyuan; Ouyang, Bin; Zhang, Chengmin; Luo, Lei; Zhao, Chen; Zhou, Qiang

    2017-01-01

    Background: Accelerated cellular senescence within the nucleus pulposus (NP) region is a common feature of disc degeneration. Our previous work indicated that TNF-α promoted NP cell senescence. Although the intervertebral disc has been reported to be an estrogen-sensitive tissue, it is unclear whether estrogen can inhibit premature senescence of NP cells. Objective: To investigate whether 17beta-estradiol (E2) can attenuate TNF-α-induced premature senescence of NP cells and the potential mechanism behind this regulatory process. Methods: Isolated NP cells and intact intervertebral discs from healthy rats were cultured with or without TNF-α, E2 or their combination. The pan estrogen receptor (ER) antagonist ICI 182780 was used to investigate the role of ER. Direct and indirect indicators including cell proliferation, SA-β-Gal activity, telomerase activity, cell cycle, and the expression of matrix macromolecules (aggrecan and collagen II) and senescence markers (p16 and p53) were used to evaluate the premature senescence of NP cells. Additionally, intracellular reactive oxygen species (ROS) and NF-κB/p65 activity were also detected in the NP cell cultures. Results: In the NP cell cultures, E2 significantly increased cell proliferation potency, telomerase activity and the expression of matrix macromolecules but attenuated SA-β-Gal activity, senescence marker (p53 and p16) expression and G1 cycle arrest in TNF-α-treated NP cells. Furthermore, E2 inhibited ROS generation and phospho-NF-κB/p65 expression in the TNF-α-treated NP cells. However, the ER antagonist ICI 182780 abolished the effects of E2 on TNF-α-treated NP cells. In the disc organ cultures, E2 also significantly increased matrix synthesis, whereas it decreased senescence marker (p53 and p16) expression, which could be abolished by the ER antagonist ICI 182780. Conclusion: The interaction between E2 and ER can attenuate TNF-α-induced premature senescence of rat NP cells through interfering with the

  20. Sensitivity of a Tier I screening battery compared to an in utero exposure for detecting the estrogen receptor agonist 17 beta-estradiol.

    PubMed

    O'Connor, J C; Frame, S R; Biegel, L B; Cook, J C; Davis, L G

    1998-08-01

    A Tier I screening battery for detecting endocrine active compounds (EACs) has been evaluated for its ability to identify 17 beta-estradiol, a pure estrogen receptor agonist. In addition, the responses obtained with the Tier I battery were compared to the responses obtained from F1 generation rats from a 90-day/one-generation reproduction study with 17 beta-estradiol in order to characterize the sensitivity of the Tier I battery against the sensitivity of an in utero exposure for detecting EACs. The Tier I battery incorporates two short-term in vivo tests (5-day ovariectomized female battery; 15-day intact male battery) and an in vitro yeast transactivation system (YTS) for identifying compounds that alter endocrine homeostasis. The Tier I female battery consists of traditional uterotrophic endpoints coupled with biochemical and hormonal endpoints. It is designed to identify compounds that are estrogenic/antiestrogenic or modulate dopamine levels. The Tier I male battery consists of organ weights coupled with microscopic evaluations and a comprehensive hormonal assessment. It is designed to identify compounds that have the potential to act as agonists or antagonists to the estrogen, androgen, progesterone, or dopamine receptor; steroid biosynthesis inhibitors (aromatase, 5 alpha-reductase, and testosterone biosynthesis); or compounds that alter thyroid function. The YTS is designed to identify compounds that bind to steroid hormone receptors (estrogen, androgen, and progesterone) and activate gene transcription. The profile generated for 17 beta-estradiol was characteristic of the responses expected with a pure estrogen receptor agonist. In the female battery, responses to 17 beta-estradiol included increases in uterine fluid imbibition, uterine weight, estrus conversion, uterine stromal cell proliferation, uterine epithelial cell height, uterine progesterone receptor content, serum prolactin and estradiol levels, and decreases in uterine estrogen receptor content

  1. Endocrine disruption of parr-smolt transformation and seawater tolerance of Atlantic salmon by 4-nonylphenol and 17beta-estradiol.

    PubMed

    McCormick, Stephen D; O'dea, Michael F; Moeckel, Amy M; Lerner, Darren T; Björnsson, Björn Thrandur

    2005-07-01

    Sex steroids are known to interfere with the parr-smolt transformation of anadromous salmonids, and environmental estrogens such as nonylphenol have recently been implicated in reduced returns of Atlantic salmon in the wild. To determine the endocrine pathways by which estrogenic compounds affect smolt development and seawater tolerance, groups of juvenile Atlantic salmon were injected with one of five doses (0.5, 2, 10, 40 or 150 microg g(-1)) of branched 4-nonylphenol (NP), 2 microg g(-1) of 17beta-estradiol (E(2)), or vehicle, during the parr-smolt transformation in April, and the treatment was repeated 4, 8, and 11 days after the first injection. Plasma was obtained for biochemical analysis 7 and 14 days after initiation of treatment. After 14 days of treatment, additional fish from each treatment group were exposed to seawater for 24h to assess salinity tolerance. The E(2) treatment and the highest NP dose resulted in lower salinity tolerance and decreased plasma insulin-like growth factor I (IGF-I) levels, along with elevated levels of plasma vitellogenin and total calcium. Plasma growth hormone levels were elevated at intermediate NP doses only, and not affected by E(2). After 7 days, plasma thyroxine (T(4)) levels decreased in a strong, dose-dependent manner in response to nonylphenol, but after 14 days, this suppressive effect of T(4) occurred at the highest NP dose only. Similarly, E(2) decreased plasma T(4) levels at 7, but not 14 days. Plasma 3,3',5-triodo-l-thyronine was reduced by E(2) and the highest NP dose after 7 and 14 days of treatment. Plasma cortisol levels were not affected by any of the treatments. The results indicate that the parr-smolt transformation and salinity tolerance can be compromised by exposure to estrogenic compounds. Suppression of plasma IGF-I levels is a likely endocrine pathway for the effects of estrogenic compounds on hypo-osmoregulatory capacity, and the detrimental effects of E(2) and NP on thyroid hormone levels are

  2. Role of 17 beta-estradiol on type IV collagen fibers volumetric density in the basement membrane of bladder wall.

    PubMed

    de Fraga, Rogerio; Dambros, Miriam; Miyaoka, Ricardo; Riccetto, Cássio Luís Zanettini; Palma, Paulo César Rodrigues

    2007-10-01

    The authors quantified the type IV collagen fibers volumetric density in the basement membrane of bladder wall of ovariectomized rats with and without estradiol replacement. This study was conducted on 40 Wistar rats (3 months old) randomly divided in 4 groups: group 1, remained intact (control); group 2, submitted to bilateral oophorectomy and daily replacement 4 weeks later of 17 beta-estradiol for 12 weeks; group 3, sham operated and daily replacement 4 weeks later of sesame oil for 12 weeks; and group 4, submitted to bilateral oophorectomy and killed after 12 weeks. It was used in immunohistochemistry evaluation using type IV collagen polyclonal antibody to stain the fibers on paraffin rat bladder sections. The M-42 stereological grid system was used to analyze the fibers. Ovariectomy had an increase effect on the volumetric density of the type IV collagen fibers in the basement membrane of rat bladder wall. Estradiol replacement in castrated animals demonstrated a significative difference in the stereological parameters when compared to the castrated group without hormonal replacement. Surgical castration performed on rats induced an increasing volumetric density of type IV collagen fibers in the basement membrane of rats bladder wall and the estradiol treatment had a significant effect in keeping a low volumetric density of type IV collagen fibers in the basement membrane of rats bladder wall.

  3. Stimulation of catecholamine synthesis through unique estrogen receptors in the bovine adrenomedullary plasma membrane by 17{beta}-estradiol

    SciTech Connect

    Yanagihara, Nobuyuki . E-mail: yanagin@med.uoeh-u.ac.jp; Liu, Minhui; Toyohira, Yumiko; Tsutsui, Masato; Ueno, Susumu; Shinohara, Yuko; Takahashi, Kojiro; Tanaka, Kazumi

    2006-01-13

    Incubation of cultured bovine adrenal medullary cells with 17{beta}-estradiol (E{sub 2}) (0.3-100 nM) or membrane-impermeable E{sub 2}-bovine serum albumin (100 nM) acutely increased {sup 14}C-catecholamine synthesis from [{sup 14}C]tyrosine. The stimulatory effect of E{sub 2} was not inhibited by ICI182,780, a nuclear estrogen receptor inhibitor. E{sub 2} also increased tyrosine hydroxylase activity and p44/42MAPK phosphorylation, the former of which was attenuated by U0126, an inhibitor of p44/42MAPK kinase. The plasma membrane isolated from the gland showed two classes of specific binding sites of [{sup 3}H]E{sub 2} with apparent K {sub d}s of 3.2 and 106 nM, and B {sub max}s of 0.44 and 8.5 pmol/mg protein, respectively. The high-affinity binding of [{sup 3}H]E{sub 2} was most strongly inhibited by E{sub 2} and phytoestrogens, and to lesser extents by other steroid hormones, while it was enhanced by ICI182,780 and environmental estrogenic pollutants. These findings suggest that E{sub 2} acutely stimulates catecholamine synthesis via activation of p44/42MAPK through unique estrogen receptors in the plasma membrane of bovine adrenal medulla.

  4. Sex differences and central protective effect of 17beta-estradiol in the development of aldosterone/NaCl-induced hypertension.

    PubMed

    Xue, Baojian; Badaue-Passos, Daniel; Guo, Fang; Gomez-Sanchez, Celso E; Hay, Meredith; Johnson, Alan Kim

    2009-05-01

    The present study tested the hypotheses that male and female rats respond differently to subcutaneous infusions of aldosterone (Aldo; 1.8 microg.kg(-1).h(-1), 1% NaCl to drink; 28 days) and that central estrogen plays a protective role against the development of hypertension. In rats with blood pressure (BP) and heart rate (HR) measured by Data Sciences International telemetry, chronic Aldo/NaCl treatment induced a greater increase in BP in males (Delta25.4 +/- 2.4 mmHg) than in females (Delta7.1 +/- 2.2 mmHg). Gonadectomy augmented Aldo/NaCl-induced hypertension in females (Delta18.2 +/- 2.0 mmHg) but had no effect in males (Delta23.1 +/- 2.9 mmHg). Immunohistochemistry for Fra-like activity was higher in the paraventricular nucleus of intact males, castrated males, and ovariectomized (OVX) females compared with intact females after 28 days of Aldo/NaCl treatment. In intact males, central 17beta-estradiol (E(2)) inhibited the Aldo/NaCl increase in BP (Delta10.5 +/- 0.8) compared with that in central vehicle plus systemic Aldo/NaCl (Delta26.1 +/- 2.5 mmHg) rats. Combined administration of E(2) and estrogen receptor antagonist ICI182780 (ICI) blocked the protective effect of E(2) (Delta23.2 +/- 2.4 mmHg). In intact females central, but not peripheral, infusions of ICI augmented the Aldo/NaCl (Delta20.4 +/- 1.8 mmHg) BP increase. Finally, ganglionic blockade after Aldo infusions resulted in a smaller reduction in BP in intact females (-23.9 +/- 2.5 mmHg) and in central estrogen-treated males (-30.2 +/- 1.0 mmHg) compared with other groups (intact males, -39.3 +/- 3.4; castrated males, -41.8 +/- 1.9; intact males with central E(2) + ICI, -42.3 +/- 2.1; OVX females, -40.3 +/- 3.3; and intact females with central ICI, -39.1 +/- 1.3 mmHg). Chronic Aldo infusion produced increases in NaCl intake and decreases in HR that were both similar in all groups. Taken together, the results indicate that central estrogen plays a protective role in the development of Aldo

  5. The effects of 17beta estradiol, 17alpha estradiol and progesterone on oxidative stress biomarkers in ovariectomized female rat brain subjected to global cerebral ischemia.

    PubMed

    Ozacmak, V H; Sayan, H

    2009-01-01

    Neuroprotective effects of estrogens and progesterone have been widely studied in various experimental models. The present study was designed to compare possible neuroprotective effects of 17alpha-estradiol, 17beta-estradiol, and progesterone on oxidative stress in rats subjected to global cerebral ischemia. Global cerebral ischemia was induced in ovariectomized female rats by four vessel occlusion for 10 min. Following 72 h of reperfusion, levels of malondialdehyde (MDA, oxidative stress marker), and reduced glutathione (GSH, major endogenous antioxidant) were assessed in hippocampus, striatum and cortex of rats treated with either 17alpha-estradiol, 17beta-estradiol, progesterone or estradiol + progesterone beforehand. Steroid administration ameliorated ischemia-induced decrease in GSH and increase in MDA levels. Our data offers additional evidence that estrogens and progesterone or combination of two exert a remarkable neuroprotective effect reducing oxidative stress.

  6. The effects of 17beta-estradiol and protein supplement on the response to purified and recombinant follicle stimulating hormone in bovine oocytes.

    PubMed

    Ali, Atef; Sirard, Marc-André

    2002-02-01

    During in vitro maturation of bovine oocytes, effects of gonadotropins (FSH, LH) and growth factors such as epidermal growth factor (EGF) vary among studies. Now that we can use defined or semi-defined medium, it becomes possible to evaluate recombinant products to assess their roles. Therefore, this study was designed to evaluate the effect of purified porcine (pFSH) or recombinant human (r-hFSH; 5, 50, or 500 ng/ml) follicle stimulating hormone, luteinising hormone (LH; 50,500 or 5000 ng/ml) and epidermal growth factor (EGF; 5, 10, 30 or 50 ng/ml) on subsequent embryonic development of in vitro matured bovine oocytes. In addition, the presence of bovine serum albumin (BSA; 8 mg/ml) as a protein supplement during in vitro maturation (IVM) was studied. For all treatments, cumulus-oocyte complexes were matured in defined maturation medium consisting of synthetic oviduct fluid. Addition of LH to the maturation medium at all concentrations studied did not increase the proportion of oocytes developing to the morula and blastocyst stages. However, morula and blastocyst yield were improved (p < 0.05) after addition of EGF (30 ng/ml) as compared with maturation medium alone (29.3% vs 18.0%, respectively). Addition of r-hFSH to the maturation medium in the presence of 17beta-estradiol (E2) significantly (p < 0.0001) increased the morula and blastocyst rate compared with maturation medium alone (40.3% vs 19.3%, respectively). The presence of BSA alone during IVM significantly reduced the developmental competence of oocytes as reflected by the morula and blastocyst yield. These results demonstrate the essential role of FSH, EGF and E2 on the kinetics of nuclear and cytoplasmic maturation that are essential for the formation of an egg capable of fertilisation and development. Also, supplementation of r-hFSH and E2 during IVM under our conditions increases morula and blastocyst yield following in vitro fertilisation and in vitro culture in defined medium. Finally, the presence

  7. Contrasting effects of increased and decreased dopamine transmission on latent inhibition in ovariectomized rats and their modulation by 17beta-estradiol: an animal model of menopausal psychosis?

    PubMed

    Arad, Michal; Weiner, Ina

    2010-06-01

    Women with schizophrenia have later onset and better response to antipsychotic drugs (APDs) than men during reproductive years, but the menopausal period is associated with increased symptom severity and reduced treatment response. Estrogen replacement therapy has been suggested as beneficial but clinical data are inconsistent. Latent inhibition (LI), the capacity to ignore irrelevant stimuli, is a measure of selective attention that is disrupted in acute schizophrenia patients and in rats and humans treated with the psychosis-inducing drug amphetamine and can be reversed by typical and atypical APDs. Here we used amphetamine (1 mg/kg)-induced disrupted LI in ovariectomized rats to model low levels of estrogen along with hyperfunction of the dopaminergic system that may be occurring in menopausal psychosis, and tested the efficacy of APDs and estrogen in reversing disrupted LI. 17beta-Estradiol (50, 150 microg/kg), clozapine (atypical APD; 5, 10 mg/kg), and haloperidol (typical APD; 0.1, 0.3 mg/kg) effectively reversed amphetamine-induced LI disruption in sham rats, but were much less effective in ovariectomized rats; 17beta-estradiol and clozapine were effective only at high doses (150 microg/kg and 10 mg/kg, respectively), whereas haloperidol failed at both doses. Haloperidol and clozapine regained efficacy if coadministered with 17beta-estradiol (50 microg/kg, an ineffective dose). Reduced sensitivity to dopamine (DA) blockade coupled with spared/potentiated sensitivity to DA stimulation after ovariectomy may provide a novel model recapitulating the combination of increased vulnerability to psychosis with reduced response to APD treatment in female patients during menopause. In addition, our data show that 17beta-estradiol exerts antipsychotic activity.

  8. Maternally derived testosterone and 17beta-estradiol in the eggs of Arctic-breeding glaucous gulls in relation to persistent organic pollutants.

    PubMed

    Verboven, Nanette; Verreault, Jonathan; Letcher, Robert J; Gabrielsen, Geir W; Evans, Neil P

    2008-08-01

    It is largely unknown if and how persistent organic pollutants (POPs) affect the transfer of maternal hormones to eggs. This occurs despite an increasing number of studies relating environmental conditions experienced by female birds at the time of egg formation to maternal hormonal effects. Here we report the concentrations of maternal testosterone, 17beta-estradiol and major classes of POPs (organochlorines, brominated flame retardants and metabolically-derived products) in the yolk of unincubated, third-laid eggs of the glaucous gull (Larus hyperboreus), a top-predator in the Arctic marine environment. Controlled for seasonal and local variation, positive correlations were found between the concentrations of certain POPs and testosterone. Contaminant-related changes in the relative concentrations of testosterone and 17beta-estradiol were also observed. In addition, yolk steroid concentrations were associated with contaminant profiles describing the proportions of different POPs present in the yolk. Eggs from nests in which two sibling eggs hatched or failed to hatch differed in POP profiles and in the relative concentrations of testosterone and 17beta-estradiol. Although the results of this correlative study need to be interpreted with caution, they suggest that contaminant-related changes in yolk steroids may occur, possibly affecting offspring performance over and above toxic effects brought about by POPs in eggs.

  9. Cosupplementation of isoflavones, prenylflavonoids, and lignans alters human exposure to phytoestrogen-derived 17beta-estradiol equivalents.

    PubMed

    Bolca, Selin; Wyns, Ciska; Possemiers, Sam; Depypere, Herman; De Keukeleire, Denis; Bracke, Marc; Verstraete, Willy; Heyerick, Arne

    2009-12-01

    The microbial metabolism of dietary phytoestrogens varies considerably among individuals and influences the final exposure to bioactive compounds. In view of the increasing number of food supplements combining several classes of phytoestrogens, the microbial potential to activate various proestrogens within an individual was evaluated in 3 randomized dietary crossovers. Treatment allocation was based on participants' eligibility (>45% in vitro bioactivation of >or=2 separate proestrogens by fecal cultures; n = 40/100). After a run-in of >or=4 d, participants were given soy-, hop-, and/or flax-based food supplements dosed either separately (SOY: 2.83 mg daidzein aglycone equivalents/supplement, HOP: 1.20 mg isoxanthohumol (IX)/supplement, or FLAX: 2.08 mg secoisolariciresinol (SECO) aglycone equivalents/supplement; reference intervention) or simultaneously (MIX; test intervention) 3 times/d for 5 d, followed by a wash-out period (>or=7 d) and the second intervention. Before and after each (co)supplementation, spot urine and serum were collected. In total, 22 equol, 19 8-prenylnaringenin (8-PN), and 21 enterolactone (ENL) producers completed the SOY+MIX, HOP+MIX, and FLAX+MIX trials, respectively. The microbial bioactivation of daidzein, IX, and SECO, generally decreased upon coincubation in vitro (equol: 4.4%, P = 0.164; 8-PN: 20.5%, P < 0.001; ENL: 44.3%, P < 0.001) and cosupplementation in vivo (equol: 28.3%, P = 0.009; 8-PN: 35.4%, P = 0.107; ENL: 35.9%, P = 0.003). Although the bioavailabilities of total isoflavones, prenylflavonoids, and lignans were not significantly affected upon coadministration, participants were exposed to lower phytoestrogen-derived 17beta-estradiol equivalents. In conclusion, the bioavailability of phytoestrogens, especially when given in mixtures, is subject to high interindividual variation. These findings support the importance of personalized screening when assessing the efficacy of such products and mixtures.

  10. Effects of 17 beta-estradiol and medroxyprogesterone acetate upon MtTW15 mammosomatotropic pituitary tumor growth and hormone production in male and female rats.

    PubMed

    Winneker, R C; Parsons, J A

    1981-05-01

    The purpose of this study was to characterize the effects of two functionally diverse steroids, 17 beta-estradiol and medroxyprogesterone acetate (MPA), on MtTW15 rat mammosomatotropic pituitary tumor growth and hormone production. Steroid responsiveness, as well as the hormonally autonomous nature of the tumor, was studied by treating both male and female tumor-bearing rats for 7 weeks with weekly injections of either 17 beta-estradiol (600 ng/g body weight/week) or MPA (200 microgram/g body weight/week) and, subsequently, comparing both the tumor weights and the in vivo production of growth hormone (GH) and prolactin (PRL) among the treatment groups. Large tumors (6 to 20 gm) were obtained in all treatment groups, indicating hormonal autonomy; however, tumors were markedly smaller, on the average, in untreated males an ovariectomized females. Treatment of such rats with 17 beta-estradiol stimulated tumor growth. Radioimmunoassay of tumor and serum GH and PRL levels in all treatment groups indicated the following: (a) tumors from untreated male or female hosts did not favor the production of one hormone over the other to any great extent; (b) MPA, however, promoted significant increases (p less than 0.05) in GH production in both male and female tumor-bearing rats while having little effect on the production of PRL; and (c) 17 beta-estradiol significantly inhibited (p less than 0.05) GH production and promoted PRL production by tumors borne by either sex. Selected studies utilizing multiple doses of MPA (1 to 500 microgram per gm body weight per week) and 17 beta-estradiol (10 to 800 ng per gm body weight per week) were accomplished and demonstrated that hormone production can be influenced in a dose-related manner. These results indicated that the estrogen-induced MtTW15 rat pituitary tumor is hormonally autonomous, yet divergently responsive to two different classes of steroidal compounds, thus making this tumor line an appropriate model for the study of

  11. Comparative study on the in vitro/in vivo estrogenic potencies of 17beta-estradiol, estrone, 17alpha-ethynylestradiol and nonylphenol.

    PubMed

    Van den Belt, K; Berckmans, P; Vangenechten, C; Verheyen, R; Witters, H

    2004-02-10

    The estrogenic activity of compounds was evaluated in a comparative approach both with in vitro and in vivo assays. By comparing simultaneously obtained experimental data, we evaluated the differences in response sensitivity (by EC10) and concentration-response relationships (including EC50) in order to get an idea about the predictive value of in vitro assays for in vivo estrogenic potencies or effects in fish. Two human estrogen receptor-based assays, the MVLN-assay (transformed MCF-7 human breast cancer cell line) and the yeast estrogen screen (YES-screen) were used for the in vitro evaluation of the estrogenic potencies. An in vivo model with the female zebrafish (Danio rerio) with plasma vitellogenin (VTG) as a biomarker for exposure and the ovarian somatic index (OSI) as an effect endpoint was used for the in vivo work. Compounds tested were 17beta-estradiol (E2), estrone (E1), 17alpha-ethynylestradiol (EE2) and the alkylphenolic compound nonylphenol (NP). All compounds were found to be estrogenic in both in vitro assays and were able to induce VTG and to reduce the ovarian somatic index in female zebrafish. The MVLN-assay appeared up to 15 times more sensitive than the YES-screen. Concentration-response relationships, determined by EC10 and EC50 (concentration of test compound causing 10% or 50% effect compared to control) for VTG and OSI were of the same order of magnitude, indicating that VTG induction as an exposure biomarker can be predictive for effects on ovaries in females. We further demonstrated that for E1 and NP, the in vitro observed estrogenic potencies, based on EC50 values, were of the same order of magnitude as the in vivo estrogenic potencies. For EE2, a difference between in vitro and in vivo relative estrogenic potency was observed, being about 25 times more potent in vivo than could be expected based on the in vitro results. These experimental results showed the suitability of in vitro assays for screening purposes with qualitative

  12. Effects of 17beta-estradiol, 4-nonylphenol and PCB 126 on the estrogenic activity and phase 1 and 2 biotransformation enzymes in male sea bass (Dicentrarchus labrax).

    PubMed

    Vaccaro, Emilia; Meucci, Valentina; Intorre, Luigi; Soldani, Giulio; Di Bello, Domenica; Longo, Vincenzo; Gervasi, Pier Giovanni; Pretti, Carlo

    2005-11-30

    The endocrine system of wildlife is exposed to a wide variety of natural and man-made chemicals which may lead to damage to the reproductive system and other adverse effects, including alteration of drug-metabolizing enzymes. In the present study, the effects of in vivo exposure to a natural (17beta-estradiol: E2) or a xenoestrogen (4-nonylphenol: NP) estrogen or an anti-estrogen (3,3',4,4',5-pentachlorobiphenyl: PCB 126) upon vitellogenin (VTG) synthesis and hepatic phase 1 and 2 enzymes have been investigated in adult male sea bass. By means of ELISA analysis with the use of polyclonal antibodies prepared against VTG purified from E2-treated sea bass, we assessed the time course and sensitivity of VTG induction in the plasma of sea bass treated with E2 at 0.1, 0.5, 2.5 and 5.0 mg/kg doses or NP at 5.0 or 50 mg/kg doses, respectively. Sea bass sensitivity to this induction was found to be similar to that of other fish species, but with a delay in maximal response. E2 treatment also caused a selective time- and dose-dependent inhibition of hepatic CYP1A-linked EROD and phase 2 glutathione S-transferase (GST) activities, without affecting the activity of CYP3A-linked 6beta-testosterone hydroxylase, (omega)- and (omega-1)-lauric acid hydroxylases or phase 2 DT-diaphorase. A similar selective inhibition on CYP1A was also observed in fish treated with 50 mg/kg NP. The results regarding CYP1A and CYP3A were also confirmed by Western blot analysis. When the sea bass were treated with either 10 or 100 microg/kg PCB 126, an AhR ligand not yet tested in vivo in fish to assess its anti-estrogenicity, a modest and selective induction of EROD and DT-diaphorase activities was observed. Interestingly, both these activities were recovered to their control levels in sea bass co-treated with 0.5 mg/kg E2 and 10 or 100 microg/kg PCB 126, probably through a cross-talk mechanism between the estrogen receptor and AhR or other transcription factors that regulate the expression of these

  13. Regulation of beta follicle stimulating hormone subunit RNA by 17-beta estradiol, progesterone, and inhibin in ovine pituitary cells in culture

    SciTech Connect

    Phillips, C.L.

    1987-01-01

    The molecular mechanism by which ovine follicle stimulating hormone (FSH) is negatively regulated by 17-beta estradiol, progesterone, and inhibin was investigated in vitro, using ovine pituitary cells in culture. The effects of these gonadal hormones on beta FSH RNA levels were assayed by dot blot hybridization to a specific radiolabeled cDNA probe for beta FSH RNA. This was compared to concomitant changes in FSH secretion, which were measured by radioimmunoassay, in order to determine if the alterations in beta FSH RNA could account for the changes in FSH secretion.

  14. [The effect of synchronization on estrus and pregnancy in sheep and on levels of thyroxine, triiodothyronine, 17 beta-estradiol, progesterone and cholesterol].

    PubMed

    Bekeová, E; Krajnicáková, M; Hendrichovský, V; Maracek, I

    1991-07-01

    Knowledge of pathogenesis of sexual dysfunctions at altered thyroid activity is limited by the knowledge of multiple and ubiquitous action of its hormones throughout the organism. One of the possibilities of modulatory influence of thyroid hormones on sexual functions can be realized through the participation of thyroxine and triiodothyronine in the synthesis and metabolism of primary substrate of steroid synthesis--cholesterol. The presented work is aimed at the study of simultaneous dynamic changes of concentrations of thyroxine (T4), triiodothyronine (T3), 17 beta-estradiol (E2), progesterone (P4) and cholesterol (Chol) during synchronization of the rutting period and gravidity at parallel correlative evaluation of mutual relations of the followed parameters in ten Merino sheep in the seasonal period. Synchronization was achieved by chlorsuperlutin (Agelin--vaginal swabs, Spofa; 20 mg of chlorsuperlutin/swab) and PMSG (500 I. U./animal). Blood was sampled by means of a jugular vein puncture at the time of swab insertion (-13th day) and after three (-10th day) and seven (-7th day) following days, at the removal of swabs and application of PMSG (-3rd day), on the day of insemination (zero day), on the 7th, 14th and 17th day and in the middle of the 2nd, 3rd, 4th and 5th month of gravidity. In the phase of oestrus synchronization a significant increase of E2 concentrations on days -7 and -3 of the experiment (0.47 +/- 0.079 and 0.542 +/- 0.177 nmol.l-1 of serum, P less than 0.001; P less than 0.001) was observed compared to the E2 values on day -13 (0.084 +/- 0.036 nmol.l-1 of serum). Parallel to these observations, marked intermittent changes of T4 (Tab. I, Graph 1) were recorded with the lowest values of this parameter observed on days -10 (41.75 +/- 20.23, P less than 0.05) and -3 (50.22 +/- 18.77, P less than 0.05) and the highest on day -7 (96.77 +/- 17.51 nmol.l-1, P less than 0.01) and day zero (85.40 +/- 19.59 nmol.l-1 of serum, P less than 0.05) in

  15. Effects of early pregnancy and acute 17 beta-estradiol administration on porcine uterine secretion, cyclic nucleotides, and catecholamines.

    PubMed

    Young, K H; Bazer, F W; Simpkins, J W; Roberts, R M

    1987-01-01

    This study investigated acute effects of 17 beta-estradiol (E) on ions, cyclic nucleotides, and catecholamines and their association with temporal changes in uterine secretory products in pregnant, cyclic, and nonpregnant gilts. Uterine flushings (UTF) and endometrium (ENDOM) from one uterine horn of nonpregnant and pregnant gilts (n = 9) were collected on days 10, 12, and 14 (n = 3). Protein, plasma inhibitor (P less than 0.05), Na+, and K+ (P less than 0.01) increased linearly in UTF of pregnant gilts. Ca2+ changed biphasically, with higher concentrations (P less than 0.01) in pregnant gilts on day 12. Endometrial cAMP and cGMP (P less than 0.05) increased between days 12 and 14 of pregnancy. The UTF norepinephrine (NE) concentrations increased (P less than 0.01) in cyclic gilts between days 12 and 14, while endometrial NE increased between days 10 and 12 and then decreased on day 14. The UTF of pregnant gilts had higher (P less than 0.05) concentrations of dopamine (DA), which peaked on day 12 and then decreased (P less than 0.01) by day 14. DA in UTF of nonpregnant gilts decreased between days 10 and 12 and remained low on day 14. A catecholamine metabolite, 3,4-dihydroxyphenylglycol, in ENDOM (P less than 0.05) and UTF (P less than 0.01) decreased linearly between days 10 and 14. The turnover rate of endometrial catecholamines was 2.4-fold higher (P less than 0.05) during early pregnancy compared with that in cyclic gilts. Effects of acute administration of exogenous E (0.5 mg) were also studied. The UTF and ENDOM were from day 11 nonpregnant gilts 0, 30, 60, and 360 min (n = 3) post-E or post-saline-ethanol (C) injection (n = 9). Potassium, plasma inhibitor (P less than 0.01), and cGMP (P less than 0.05) increased rapidly (30 min) after E injection. The K+ level changed biphasically, with increased concentrations again at 360 min. Plasmin inhibitor returned to levels similar to controls by 60 min, whereas cGMP remained elevated until 360 min postinjection

  16. Estrogen receptor alpha, fos-related antigen-2, and c-Jun coordinately regulate human UDP glucuronosyltransferase 2B15 and 2B17 expression in response to 17beta-estradiol in MCF-7 cells.

    PubMed

    Hu, Dong Gui; Mackenzie, Peter I

    2009-08-01

    UDP-glucuronosyltransferase 2B15 and 2B17 expression is up-regulated by 17beta-estradiol in MCF-7 breast cancer cells, as assessed by quantitative real-time polymerase chain reaction. Using 5'-deletion mapping and site-directed mutagenesis, we demonstrate that 17beta-estradiol activation of UGT2B15 gene transcription is mediated by a 282-base pair fragment positioned -454 to -172 nucleotides from the translation start site. This region contains two putative activator protein-1 (AP-1) elements, one imperfect estrogen response element (ERE), and two consensus ERE half-sites. We propose that these five sites act as an estrogen response unit (ERU), because mutation in any site reduces activation of the UGT2B15 promoter by 17beta-estradiol. Despite the presence of two AP-1 elements, the UGT2B15 promoter is not responsive to the AP-1 activator phorbol 12-myristate 13-acetate. Although electrophoretic mobility shift assays (EMSA) indicate that the AP-1 proteins c-Jun and Fos-related antigen 2 (Fra-2) bound to the distal AP-1 site, binding of Jun or Fos family members to the proximal AP-1 site was not detected by EMSA. Chromatin immunoprecipitation assays showed a 17beta-estradiol-induced recruitment of estrogen receptor (ER) alpha, c-Jun, and Fra-2 to the 282-bp ERU. The involvement of these three transcription factors in the stimulation of UGT2B15 gene expression by 17beta-estradiol was confirmed by siRNA silencing experiments. Mutagenesis and siRNA experiments indicate that UGT2B17 expression is also regulated by 17beta-estradiol via the ERU, which is fully conserved in both promoters. Because UGT2B15 and UGT2B17 inactivate steroid hormones by glucuronidation, the regulation of their genes by 17beta-estradiol may maintain steroid hormone homeostasis and prevent excessive estrogen signaling activity.

  17. The somatotropic axis in postmenopausal women during six month of transdermal continuous 17beta-estradiol administration combined with oral medroxyprogesterone.

    PubMed

    Milewicz, Tomasz; Krzysiek, Józef; Rogatko, Iwona; Sztefko, Krystyna; Stochmal, Ewa; Hubalewska-Dydejczyk, Alicja; Jach, Robert; Radowicki, Stanisław

    2011-04-01

    The evaluation of the influence of continuous transdermal estradiol supplementation combined with oral medroxyprogesterone on the somatotropic axis in postmenopausal women. 25 women completed the study Group A--13 women received transdermal 17beta-estradiol (Oesclim 50 - Fournier-Solvay) combined with oral 5 mg daily medroxyprogesterone (Gestomikron - Adamed). Group B--12 women without treatment. Basic plasma FSH, estradiol, glucose, insulin, SHBG, hGH, total and free IGF-I, IGFBP-1 as well as IGFBP-3 were measured initially and at the 12th and 24th week of the study. The mean plasma FSH level was reduced and mean plasma estradiol level was increased in group A during estradiol supplementation. Mean plasma level of free IGF-I and free to total IGF-I ratio were increased in group A during 24 weeks of hormone therapy. In the control group (group B) there was the significant increase in mean plasma IGFBP-3 level. Other parameters showed no significant changes in the control group. The administration of transdermal 17beta-estradiol combined with oral medroxyprogesterone increases the IGF-I bioavailability. However this influence do not exceed the physiologial level of IGF-I bioavailability.

  18. Biosynthesis and secretion of follicle-stimulating hormone beta-subunit from ovine pituitary cultures: effect of 17 beta-estradiol treatment

    SciTech Connect

    Whitfield, G.K.; Miller, W.L.

    1984-07-01

    An assay was developed to detect tritium-labeled ovine FSH beta-subunit (( /sup 3/H)oFSH beta) secreted from primary ovine pituitary cultures. This procedure used affinity-enriched antibodies raised against reduced and carbamylmethylated oFSH beta (RCM-oFSH beta) in a two-cycle immunoextraction procedure. A discrete species with an apparent mol wt of 21,000 was detected in sodium dodecyl sulfate electrophoretic patterns of immunoextracts from culture medium. This species was identified as RCM-(/sup 3/H)oFSH beta by its comigration with highly purified RCM-oFSH beta, its reduction in culture media after cultures were treated with 17 beta-estradiol, which normally decreases radioimmunoassayable oFSH; and its displacement from the extracting antibodies by excess unlabeled RCM-oFSH beta. The assay was used in a pulse-chase study to determine that (/sup 3/H)oFSH beta is secreted within 1-2 h of its synthesis. Prior treatment of cultures with 17 beta-estradiol did not change this timing of secretion.

  19. Increased chromogranin A and neuron-specific enolase in rats with chronic nonbacterial prostatitis induced by 17-beta estradiol combined with castration

    PubMed Central

    Fan, Song; Hao, Zong-Yao; Zhang, Li; Chen, Xian-Guo; Zhou, Jun; Zang, Yi-Fei; Tai, Sheng; Liang, Chao-Zhao

    2014-01-01

    Although chronic nonbacterial prostatitis (CNBP) is a common diagnosis in middle-aged men, the etiology of this disease remains poorly understood. Neuroendocrine cells play an important role in the neuroendocrine regulation of the prostate, and chromogranin A (CgA) and neuron-specific enolase (NSE) are regarded as classic markers of neuroendocrine cells. This study aimed to determine CgA and NSE levels in a CNBP rat model to evaluate the role of neuroendocrine cells in the pathogenesis of CNBP. For developing a CNBP rat model, we examined the ability of 17-beta estradiol and surgical castration alone or in combination to induce CNBP. Histologic inflammation of the prostate was assessed in CNBP-induced rats by hematoxylin-eosin staining, whereas CgA and NSE protein levels were assessed by immunohistochemistry, Western blot analysis, and enzyme-linked immunosorbent assays. Our results showed that 17-beta estradiol combined with castration successfully induced CNBP and that CgA and NSE levels were increased in the prostate of CNBP rats as compared to those without CNBP. These findings indicate that the neuroendocrine regulation mediated by neuroendocrine cells may be involved in the pathogenesis of CNBP. PMID:25120776

  20. 17Beta-estradiol protects against oxidative stress-induced cell death through the glutathione/glutaredoxin-dependent redox regulation of Akt in myocardiac H9c2 cells.

    PubMed

    Urata, Yoshishige; Ihara, Yoshito; Murata, Hiroaki; Goto, Shinji; Koji, Takehiko; Yodoi, Junji; Inoue, Satoshi; Kondo, Takahito

    2006-05-12

    The GSH/glutaredoxin (GRX) system is involved in the redox regulation of certain enzyme activities, and this system protects cells from H2O2-induced apoptosis by regulating the redox state of Akt (Murata, H., Ihara, Y., Nakamura, H., Yodoi, J., Sumikawa, K., and Kondo, T. (2003) J. Biol. Chem. 278, 50226-50233). Estrogens, such as 17beta-estradiol (E2), play an important role in development, growth, and differentiation and appear to have protective effects on oxidative stress mediated by estrogen receptor alpha (ERalpha). However, the role of the ERbeta-mediated pathway in this cytoprotection and the involvement of E2 in the redox regulation are not well understood. In the present study, we demonstrated that E2 protected cardiac H9c2 cells, expressing ERbeta from H2O2-induced apoptosis concomitant with an increase in the activity of Akt. E2 induced the expression of glutaredoxin (GRX) as well as gamma-glutamylcysteine synthetase, a rate-limiting enzyme for the synthesis of GSH. Inhibitors for both gamma-glutamylcysteine synthetase and GRX and ICI182,780, a specific inhibitor of ERs, abolished the protective effect of E2 on cell survival as well as the activity of Akt, suggesting that ERbeta is involved in the cytoprotection and redox regulation by E2. Transcription of the GRX gene was enhanced by E2. The promoter activity of GRX was up-regulated by an ERbeta-dependent element. These results suggest that the GRX/GSH system is involved in the cytoprotective and genomic effects of E2 on the redox state of Akt, a pathway that is mediated, at least in part, by ERbeta. This mechanism may also play an antiapoptotic role in cancer cells during carcinogenesis or chemotherapy.

  1. Removal of estrone, 17alpha-ethinylestradiol, and 17beta-estradiol in algae and duckweed-based wastewater treatment systems.

    PubMed

    Shi, Wenxin; Wang, Lizheng; Rousseau, Diederik P L; Lens, Piet N L

    2010-05-01

    Many pollutants have received significant attention due to their potential estrogenic effect and are classified as endocrine disrupting compounds (EDCs). Because of possible ecological effects and increased attention for water reuse schemes, it is important to increase our understanding of the EDC removal capacities of various wastewater treatment systems. However, there has so far been little research on the fate and behavior of EDCs in stabilization pond systems for wastewater treatment, which represent an important class of wastewater treatment systems in developing countries because of their cost-effectiveness. The aim of this work is to study the fate and behavior of EDCs in algae and duckweed ponds. Because the synthetic hormone 17alpha-ethinylestradiol (EE2) and the natural hormones estrone (E1), as well as 17beta-estradiol (E2), have been detected in effluents of sewage treatment plants and been suggested as the major compounds responsible for endocrine disruption in domestic sewage; E1, E2, and EE2 were therefore chosen as target chemicals in this current work. Both batch tests and continuous-flow tests were carried out to investigate the sorption and biodegradation of estrogens in algae and duckweed pond systems. The applied duckweed was a Lemna species. The applied algae was a mixture of pure cultures of six different algae genera, i.e., Anabaena cylindrica, Chlorococcus, Spirulina platensis, Chlorella, Scenedesmus quadricauda, and Anaebena var. Synthetic wastewater were used in all tests. The concentrations of estrogens were measured with three different enzyme-linked immunosorbent assay kits specific for E1, E2, or EE2. When the concentrations of estrogens in water samples were below the lowest quantitative analysis range (0.05 microg/l), preconcentration of the water samples were performed by means of solid phase extraction (SPE) with C18 cartridges. The 6-day batch tests show that the presence of algae or duckweed accelerated the removal of the three

  2. 17beta-estradiol at physiological concentrations augments Ca(2+) -activated K+ currents via estrogen receptor beta in the gonadotropin-releasing hormone neuronal cell line GT1-7.

    PubMed

    Nishimura, Ichiro; Ui-Tei, Kumiko; Saigo, Kaoru; Ishii, Hirotaka; Sakuma, Yasuo; Kato, Masakatsu

    2008-02-01

    Estrogens play essential roles in the neuroendocrine control of reproduction. In the present study, we focused on the effects of 17beta-estradiol (E2) on the K(+) currents that regulate neuronal cell excitability and carried out perforated patch-clamp experiments with the GnRH-secreting neuronal cell line GT1-7. We revealed that a 3-d incubation with E2 at physiological concentrations (100 pm to 1 nm) augmented Ca(2+)-activated K(+) [K(Ca)] currents without influencing Ca(2+)-insensitive voltage-gated K(+) currents in GT1-7 cells. Acute application of E2 (1 nm) had no effect on the either type of K(+) current. The augmentation was completely blocked by an estrogen receptor (ER) antagonist, ICI-182,780. An ERbeta-selective agonist, 2,3-bis(4-hydroxyphenyl)-propionitrile, augmented the K(Ca) currents, although an ERalpha-selective agonist, 4,4',4''-[4-propyl-(1H)-pyrazole-1,3,5-triyl]tris-phenol, had no effect. Knockdown of ERbeta by means of RNA interference blocked the effect of E2 on the K(Ca) currents. Furthermore, semiquantitative RT-PCR analysis revealed that the levels of BK channel subunit mRNAs for alpha and beta4 were significantly increased by incubating cells with 300 pm E2 for 3 d. In conclusion, E2 at physiological concentrations augments K(Ca) currents through ERbeta in the GT1-7 GnRH neuronal cell line and increases the expression of the BK channel subunit mRNAs, alpha and beta4.

  3. Gender-specific expression of multiple estrogen receptors, growth hormone receptors, insulin-like growth factors and vitellogenins, and effects of 17 beta-estradiol in the male tilapia (Oreochromis mossambicus).

    PubMed

    Davis, Lori K; Pierce, Andrew L; Hiramatsu, Naoshi; Sullivan, Craig V; Hirano, Tetsuya; Grau, E Gordon

    2008-05-01

    Gender-specific expression of estrogen receptors (ER alpha and ER beta), growth hormone receptors (GHR1 and GHR2), insulin-like growth factors (IGF-I and IGF-II) and three vitellogenins (Vgs A-C) was examined in the liver, gonad, pituitary, and brain of sexually mature male, female, and 17 beta-estradiol (E2)-treated male tilapia (Oreochromis mossambicus). Reflecting greater growth rate in male tilapia, hepatic expression of GHR1, GHR2, IGF-I and IGF-II as well as plasma IGF-I levels were higher in males than in females, whereas the expression of Vgs A-C and ER alpha was higher in females. On the other hand, expression of all genes measured was higher in the ovary than in testis. Forty eight hours after E2 injection (5 microg/g) into male fish, hepatic expression of most transcripts measured were altered to levels that were similar to those seen in females. The changes included decreased expression of GHR1, GHR2, IGF-I, and IGF-II, and increased expression of ER alpha and Vgs A-C. E2 treatment also increased Vg and decreased IGF-I in the plasma. Brain expression of ER alpha, ER beta, GHR1, and IGF-I was higher in females than in males, whereas pituitary expression of GHR2 and IGF-I was lower in females; only brain expression of GHR1 was increased by E2 treatment. These findings suggest that E2 stimulates Vg production primarily through activation of ER alpha and down-regulation of the GH/IGF-I axis, thus shifting energy from somatic growth towards vitellogenesis at the level of the liver.

  4. Low 17beta-estradiol levels in CNR1 knock-out mice affect spermatid chromatin remodeling by interfering with chromatin reorganization.

    PubMed

    Cacciola, Giovanna; Chioccarelli, Teresa; Altucci, Lucia; Ledent, Catherine; Mason, J Ian; Fasano, Silvia; Pierantoni, Riccardo; Cobellis, Gilda

    2013-06-01

    The type 1-cannabinoid receptor, CNR1, regulates differentiation of spermatids. Indeed, we have recently reported that the genetic inactivation of Cnr1 in mice influenced chromatin remodeling of spermatids, by reducing histone displacement and then sperm chromatin quality indices (chromatin condensation and DNA integrity). Herein, we have studied, at both central and testicular levels, the molecular signals potentially involved in histone displacement. In particular, investigation of the neuroendocrine axis involved in estrogen production demonstrated down-regulation of the axis supporting FSH/estrogen secretion in Cnr1-knockout male mice. Conversely, Cnr1-knockout male mice treated with 17beta-estradiol showed a weak increase of pituitary Fsh-beta subunit mRNA levels and a rescue of sperm chromatin quality indices demonstrating that estrogens, possibly in combination with FSH secretion, play an important role in regulating chromatin remodeling of spermatids.

  5. 17beta-estradiol pretreatment reduces CA1 sector cell death and the spontaneous hyperthermia that follows forebrain ischemia in the gerbil.

    PubMed

    Plahta, W C; Clark, D L; Colbourne, F

    2004-01-01

    Pretreatment with 17beta-estradiol attenuates ischemia-induced hippocampal cornu ammonis 1 (CA1) neuronal death. We assessed whether this is mediated through prevention of hyperthermia that normally follows ischemia in gerbils. Male gerbils were given sustained-released 17beta-estradiol pellets or sham operation. Later, a guide cannula was implanted for brain temperature measurement and some were implanted with core temperature telemetry probes. Gerbils were subjected to either 5 min bilateral carotid artery occlusion or sham procedures 2 weeks after pellet surgery. Brain temperature was normothermic during surgery in all cases. In experiment 1, only core temperature was measured afterward in untreated and estrogen-treated gerbils. In experiment 2, postischemic core temperature was measured in untreated and two estrogen-treated ischemic groups, one of which had their postischemic temperature increased, via infrared lamp, to mimic the untreated group. Habituation was assessed on days 5 and 6. Hyperthermia, like that which occurs spontaneously, was forced on untreated and estrogen-treated ischemic animals in the third experiment, where brain temperature was measured. CA1 cell counts were assessed after a 7-day survival. A fourth experiment measured brain and core temperature simultaneously in normal gerbils during heating with an infrared lamp. Estrogen did not affect core temperature of non-ischemic gerbils whereas spontaneous postischemic hyperthermia was blocked. Estrogen reduced cell death and provided behavioral protection when gerbils regulated their own core temperature, but not when core hyperthermia was enforced. Conversely, estrogen reduced cell death in gerbils that had their brain temperature elevated. Experiment 4 showed that the brain becomes overheated (by approximately 1 degree C) when core temperature is elevated. Accordingly, estrogen likely failed to reduce CA1 injury in experiment 2, when core hyperthermia was enforced, because of overheating the

  6. Predicted no-effect concentration and risk assessment for 17-[beta]-estradiol in waters of China.

    PubMed

    Wu, Fengchang; Fang, Yixiang; Li, Yushuang; Cui, Xiaoyong; Zhang, Ruiqing; Guo, Guanghui; Giesy, John P

    2014-01-01

    Contamination of the aquatic environment by EDCs has received considerable attention from scientists, government officials, and the public. E2, one of the EDCs with high estrogenic effect, has the potential to cause multiple endocrine-disrupting effects, even at small concentrations. In the present review, the toxicity of E2 to aquatic organisms was reviewed. Results of published studies show that, for aquatic species, reproductive effects were the most sensitive endpoint for E2 exposure.Although the risks posed by EDCs have caused much attention, the research on the WQC 'for EDCs is still at the initial stage. It has been suggested in several reports that the PNEC can be regarded as the most appropriate reference value for developing WQC for the EDCs. The SSD method was applied to derive PNECs that were based on reproductive effects endpoints. In the present review, 31 NOECs, based on reproductive effect endpoints for different species, were selected to construct the curve. ThePNEC value was determined to be 0.73 ng E2/L, which could protect the biodiversity of aquatic ecosystems. Moreover, 6 NOECs for multigeneration species were also analyzed in anticipation of sensitivity comparison between the Fa and the F1 generations.When multiple generations of aquatic species were exposed to concentrations no greater than 100 ng E2/L, nearly 71.4% of the F 1 generation individuals were more sensitive to the effects of E2 than those of the Fa generation. This result indicated that different generations of the same species may respond differently to EDCs exposure.Individuals of the F 1 generation were slightly more sensitive than those of the Fa generation,in general. Therefore, protecting the F1 generation of aquatic organisms is particularly important when WQC values for the EDCs are established.Considering the toxic effects of EDCs on reproduction, long-term toxic effects(viz., full-life cycle study and the most sensitive life stage) should be used in setting

  7. PLASMA CLEARANCE OF VITELLOGENIN IN SHEEPSHEAD MINNOWS AFTER CESSATION OF EXPOSURE TO 17BETA-ESTRADIOL AND PARA-NONYLPHENOL

    EPA Science Inventory

    Two experiments were performed to determine the rate of vitellogenin plasma accumulation and clearance in male sheepshead minnows (Cyprinodon variegatus) during and after exposure to either 17b-estradiol (E2) or para-nonylphenol (p-NP). Adult fish were continuously exposed to aqu...

  8. Comparison between urinary pyridinium cross-links and hydroxylysine glycosides in monitoring the effects of ovariectomy and 17 beta-estradiol replacement in aged rats.

    PubMed

    Pecile, A; Netti, C; Sibilia, V; Villa, I; Calori, G; Tenni, R; Coluzzi, M; Moro, G L; Rubinacci, A

    1996-09-01

    This study was undertaken to assess the sensitivity of hydroxylysylpyridinoline (HP), lysylpyridinoline (LP), galactosylhydroxylysine (GHyl) and glucosylgalactosylhydroxylysine (GGHyl) to monitor bone response to estrogen deficiency and replacement by comparing their excretory patterns in ovariectomized aged (11-14 months old) rats. The ovariectomized (OVX) rats were randomized into two groups: (1) OVX plus vehicle; (2) OVX plus 17 beta-estradiol (17-beta E, 10 micrograms/kg, s.c., 4 days/week). Treatment with 17-beta E started immediately after OVX and continued for 60 days. The collagen catabolites were measured in urine for 1 month before OVX and thereafter for 60 days. In temporal coincidence with urine collection, bone area and bone mineral density (BMD) of lumbar vertebrae, femoral diaphysis and distal metaphysis were measured by dual-energy X-ray absorptiometry. In the untreated rats, BMD of the femoral metaphysis and lumbar vertebrae decreased significantly and the urinary excretion of LP, HP, GHyl and GGHyl increased with different patterns. In the treated rats, 17-beta E replacement prevented the increment in LP excretion, partially prevented the increase in HP excretion, but had no effect on the excretion of GHyl and GGHyl. In conclusion pyridinolines and glycosides have different sensitivities to the bone response to OVX. Glycoside excretion after OVX also reflects metabolic processes not strictly related to bone loss and, in contrast with LP, is not sensitive to estrogen replacement.

  9. Identification of centrarchid hepcidins and evidence that 17beta-estradiol disrupts constitutive expression of hepcidin-1 and inducible expression of hepcidin-2 in largemouth bass (Micropterus salmoides).

    PubMed

    Robertson, Laura S; Iwanowicz, Luke R; Marranca, Jamie Marie

    2009-06-01

    Hepcidin is a highly conserved antimicrobial peptide and iron-regulatory hormone. Here, we identify two hepcidin genes (hep-1 and hep-2) in largemouth bass (Micropterus salmoides) and smallmouth bass (Micropterus dolomieu). Hepcidin-1 contains a putative ATCUN metal-binding site in the amino-terminus that is missing in hepcidin-2, suggesting that hepcidin-1 may function as an iron-regulatory hormone. Both hepcidins are predominately expressed in the liver of largemouth bass, similar to other fish and mammals. Experimental exposure of pond-raised largemouth bass to 17beta-estradiol and/or the bacteria Edwardsiella ictaluri led to distinct changes in expression of hep-1 and hep-2. Estradiol reduced the constitutive expression of hep-1 in the liver. Bacterial exposure induced expression of hep-2, suggesting that hepcidin-2 may have an antimicrobial function, and this induction was abolished by estradiol. To our knowledge, this is the first report of the regulation of hepcidin expression by estradiol in either fish or mammals.

  10. Reproductive experience reduces circulating 17beta-estradiol and prolactin levels during proestrus and alters estrogen sensitivity in female rats.

    PubMed

    Bridges, Robert S; Byrnes, Elizabeth M

    2006-05-01

    The reproductive experiences of pregnancy, parturition, and lactation affect a range of neural and endocrine processes after the end of lactation. In women, previous parity results in reduced circulating prolactin (PRL) and androgen levels years after giving birth. Reductions in PRL secretion also occur in reproductively experienced, female rats. In the present study we examined the status and regulation of estradiol (E(2)) and PRL during the reproductive cycle after reproductive experience. These hormones regulate one another and have been implicated in a number of disease and aging processes. Using a rat model, the patterns of E(2) and PRL secretion, pituitary PRL content, and estrogen receptor alpha expression were characterized from 1200-1800 h on proestrus in age-matched, primiparous and nulliparous animals. The possible effect of parity on estrogen sensitivity was then examined by challenging nonlactating, ovariectomized, age-matched, multiparous and nulliparous rats with estradiol benzoate (EB; 0, 1, 5, 25, and 125 microg/kg) and measuring PRL responses 24 and 48 h later. Previous parity resulted in modest, yet significant, reductions in E(2) and PRL levels on proestrus, a limited increase in pituitary estrogen receptor alpha expression, and a significant shift in estrogen sensitivity, as measured by EB-induced PRL secretion. Nulliparous animals were more sensitive than multiparous rats to the two lower doses of EB, whereas multiparous animals were more responsive to the highest EB dose. These unique parity-induced alterations in the female's endocrine state that persist beyond lactation may impact a multitude of estrogen-mediated processes over the female's adult life span.

  11. Development of Simultaneous Derivative Spectrophotometric and HPLC Methods for Determination of 17-Beta-Estradiol and Drospirenone in Combined Dosage Form

    PubMed Central

    Aydoğmuş, Zeynep; Yılmaz, Ece Merve; Yörüsün, Sevgi; Akpınar, Samet

    2015-01-01

    Simple, rapid spectrophotometric, and reverse-phase high performance liquid chromatographic methods were developed for the concurrent analysis of 17-beta-estradiol (ESR) and drospirenone (DRS). The spectrophotometric method was based on the determination of first derivative spectra and determined ESR and DRS using the zero-crossing technique at 208 and 282 nm, respectively, in methanol. The linear range was 0.5–32.0 µg·mL−1 for DRS and 0.5–8.0 µg·mL−1 for EST. The limit of detection (LOD) values were 0.14 µg·mL−1 and 0.10 µg·mL−1 and limit of quantification (LOQ) values were 0.42 µg·mL−1 and 0.29 µg·mL−1 for ESR and DRS, respectively. The chromatographic method was based on the separation of both analytes on a C18 column with a mobile phase containing acetonitrile and water (70 : 30, v/v). Detection was performed with a UV-photodiode array detector at 279 nm. The linear range was 0.08–2.5 µg·mL−1 for DRS and 0.23–7.5 µg·mL−1 for EST. LOD values were 0.05 µg·mL−1 and 0.02 µg·mL−1 and LOQ values were 0.15 µg·mL−1 and 0.05 µg·mL−1 for ESR and DRS, respectively. These recommended methods have been applied for the simultaneous determination of ESR and DRS in their tablets. PMID:27347530

  12. Beneficial effect of 17{beta}-estradiol on hyperglycemia and islet {beta}-cell functions in a streptozotocin-induced diabetic rat model

    SciTech Connect

    Yamabe, Noriko; Kang, Ki Sung; Zhu Baoting

    2010-11-15

    The modulating effect of estrogen on glucose homeostasis remains a controversial issue at present. In this study, we sought to determine the beneficial effect of 17{beta}-estradiol (E{sub 2}) on hyperglycemia and islet {beta}-cell functions in streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats were injected i.p. with STZ to induce a relatively mild diabetic condition. The rats were then treated with E{sub 2} orally at 500 {mu}g/kg body weight/day for 15 days to evaluate the modulating effect on hyperglycemia, insulin secretion, and islet {beta}-cell proliferation. E{sub 2} administration for 10 days significantly lowered plasma glucose levels, increased plasma insulin levels, and improved glucose tolerance by attenuating insulin response to oral glucose loading. These beneficial effects of E{sub 2} were accompanied by increases in islet number and volume, rate of islet cell proliferation, and the amount of insulin secreted. The growth-stimulatory effect of E{sub 2} on islet cells was linked to the functions of the estrogen receptor {alpha}. Notably, these protective effects of E{sub 2} on diabetic conditions were basically not observed when the STZ-treated rats had a more severe degree of islet damage and hyperglycemia. Taken together, we conclude that E{sub 2} can promote the regeneration of damaged pancreatic islets by stimulating {beta}-cell proliferation in diabetic rats, and this effect is accompanied by improvements in glucose tolerance and a decrease in plasma glucose levels. These findings suggest that oral administration of E{sub 2} may be beneficial in diabetic patients with an accelerated loss of islet {beta}-cells.

  13. Melatonin reduces LH, 17 beta-estradiol and induces differential regulation of sex steroid receptors in reproductive tissues during rat ovulation

    PubMed Central

    2011-01-01

    Background Melatonin is associated with direct or indirect actions upon female reproductive function. However, its effects on sex hormones and steroid receptors during ovulation are not clearly defined. This study aimed to verify whether exposure to long-term melatonin is able to cause reproductive hormonal disturbances as well as their role on sex steroid receptors in the rat ovary, oviduct and uterus during ovulation. Methods Twenty-four adult Wistar rats, 60 days old (+/- 250 g) were randomly divided into two groups. Control group (Co): received 0.9% NaCl 0.3 mL + 95% ethanol 0.04 mL as vehicle; Melatonin-treated group (MEL): received vehicle + melatonin [100 μg/100 g BW/day] both intraperitoneally during 60 days. All animals were euthanized by decapitation during the morning estrus at 4 a.m. Results Melatonin significantly reduced the plasma levels of LH and 17 beta-estradiol, while urinary 6-sulfatoximelatonin (STM) was increased at the morning estrus. In addition, melatonin promoted differential regulation of the estrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR) and melatonin receptor (MTR) along the reproductive tissues. In ovary, melatonin induced a down-regulation of ER-alpha and PRB levels. Conversely, it was observed that PRA and MT1R were up-regulated. In oviduct, AR and ER-alpha levels were down-regulated, in contrast to high expression of both PRA and PRB. Finally, the ER-beta and PRB levels were down-regulated in uterus tissue and only MT1R was up-regulated. Conclusions We suggest that melatonin partially suppress the hypothalamus-pituitary-ovarian axis, in addition, it induces differential regulation of sex steroid receptors in the ovary, oviduct and uterus during ovulation. PMID:21810236

  14. Hepatic estrogen receptor and plasma 17{beta}-estradiol concentrations as biomarkers of 2,3,7,8-TCDD exposure in avian hatchlings

    SciTech Connect

    Janz, D.M.; Bellward, G.D.

    1995-12-31

    The authors have been investigating the sensitivity of various toxicologically relevant endpoints as environmental biomarkers in avian hatchlings exposed in ovo to 2,3,7,8-TCDD. Potential biomarkers included various endocrine endpoints such as plasma 17{beta}-estradiol (E{sub 2}), hepatic estrogen receptor (ER) affinities and concentrations, and plasma thyroid hormones, which were compared to hepatic ethoxyresorufin O-deethylase (EROD) induction. The animal models used were domestic chickens and pigeons, and great blue herons. An experiment conducted in pigeon hatchlings compared ``early`` (embryonic day 4; E4) vs. ``late`` (E14) in ovo exposure to 1 {micro}g/kg and 3 {micro}g/kg of TCDD, respectively. Birds were sacrificed on day of hatch (H) and day 7 after hatch (D7). In the late exposure experiment, plasma E{sub 2} concentrations were reduced at H and elevated at D7 in the TCDD-exposed birds (p < 0.05). Hepatic ER concentrations were elevated at H (p < 0.01). Although EROD was half-maximally induced at H and D7 in the early exposure experiment in pigeons, there was no effect of TCDD treatment on E, or ER levels. The nominal TCDD concentration in these pigeons (1 {micro}g/kg egg) was within the range observed in wild piscivorous bird eggs collected from aquatic systems contaminated with TCDD and related chemicals (approx. 0.5--2 ng TEQ/g egg). In herons exposed to 2 {micro}g/kg of TCDD at the midpoint of incubation, hepatic ER affinities (Kd) and concentrations (Bmax) were elevated in treated birds at H (p < 0.05); however there was no effect on plasma E, levels. Liver [{sup 3}H]-TCDD concentrations were 11.3 {+-} 0.8 ng/g at H, and 0.8 {+-} 0.1 ng/g at D7, representing 9.9% and 4.9% of the nominal TCDD dose, respectively.

  15. Exposure to developing females induces polyuria, polydipsia, and altered urinary levels of creatinine, 17beta-estradiol, and testosterone in adult male mice (Mus musculus).

    PubMed

    deCatanzaro, Denys; Khan, Ayesha; Berger, Robert G; Lewis, Elaine

    2009-01-01

    Novel male mice can accelerate reproductive maturation in proximal developing females, an effect mediated by the chemistry of the males' urine. Exogenous estrogens can similarly accelerate female sexual development. In Experiment 1, adult male mice were housed across wire grid from either empty compartments or those containing post-weanling females. Proximity of females caused males to urinate more, progressively over days of exposure, with most urination directed towards females' compartments. Male urine collected after 5 days in these conditions was analyzed by enzyme immunoassay for 17beta-estradiol, testosterone, and creatinine. Urinary creatinine of isolated males significantly exceeded that of female-exposed males. Unadjusted urinary steroids also trended toward higher levels in isolates, but creatinine-adjusted estradiol and testosterone of female-exposed males significantly exceeded that of isolated males. In Experiment 2, measurement of water consumption indicated significantly greater drinking by female-exposed as opposed to isolated males. In Experiment 3, males were housed in isolation or beside post-weanling intact (sham-operated) females, ovariectomized females, or intact (sham-operated) males. Male water consumption was elevated in all conditions involving social contact. Urinary creatinine was significantly lower in female-exposed males compared to isolated controls, while unadjusted testosterone was significantly lower in males in all social conditions. Again, creatinine-adjusted estradiol in female-exposed males significantly exceeded that of isolates. These data indicate that adult males drink and urinate more, have more dilute urine, and have a higher ratio of estradiol to creatinine when they are near developing females. These dynamics increase females' exposure to urinary steroids and other urinary constituents that can hasten sexual maturity.

  16. Rainfall and tillage effects on transport of fecal bacteria and sex hormones 17beta-estradiol and testosterone from broiler litter applications to a Georgia Piedmont Ultisol.

    PubMed

    Jenkins, Michael B; Truman, Clint C; Siragusa, Gregory; Line, Eric; Bailey, J Stan; Frye, Jonathan; Endale, Dinku M; Franklin, Dorcas H; Schomberg, Harry H; Fisher, Dwight S; Sharpe, Ronald R

    2008-09-15

    Poultry litter provides nutrients for crop and pasture production; however, it also contains fecal bacteria, sex hormones (17beta-estradiol and testosterone) and antibiotic residues that may contaminate surface waters. Our objective was to quantify transport of fecal bacteria, estradiol, testosterone and antibiotic residues from a Cecil sandy loam managed since 1991 under no-till (NT) and conventional tillage (CT) to which either poultry litter (PL) or conventional fertilizer (CF) was applied based on the nitrogen needs of corn (Zea mays L) in the Southern Piedmont of NE Georgia. Simulated rainfall was applied for 60 min to 2 by 3-m field plots at a constant rate in 2004 and variable rate in 2005. Runoff was continuously measured and subsamples taken for determining flow-weighted concentrations of fecal bacteria, hormones, and antibiotic residues. Neither Salmonella, nor Campylobacter, nor antimicrobial residues were detected in litter, soil, or runoff. Differences in soil concentrations of fecal bacteria before and after rainfall simulations were observed only for Escherichia coli in the constant rainfall intensity experiment. Differences in flow-weighted concentrations were observed only for testosterone in both constant and variable intensity rainfall experiments, and were greatest for treatments that received poultry litter. Total loads of E. coli and fecal enterococci, were largest for both tillage treatments receiving poultry litter for the variable rainfall intensity. Load of testosterone was greatest for no-till plots receiving poultry litter under variable rainfall intensity. Poultry litter application rates commensurate for corn appeared to enhance only soil concentrations of E. coli, and runoff concentrations of testosterone above background levels.

  17. Comparison of pharmacokinetic profiles of a 17 beta-estradiol gel 0.6 mg/g (Gelestra) with a transdermal delivery system (Estraderm TTS 50) in postmenopausal women at steady state.

    PubMed

    Paoletti, A M; Pilia, I; Nannipieri, F; Bigini, C; Melis, G B

    2001-12-14

    to compare the patterns of a 17 beta-estradiol (E(2)) gel containing 0.6 mg/g (1.5 mg E(2) per day, Gelestra); with the transdermal delivery system (Estraderm TTS 50) applied every 3 days over a 14-day period to women in spontaneous or surgical menopause. a single centre, open, randomised, parallel-group study was conducted. A total number of 33 postmenopausal women were enrolled. In 23 of them the menopause occurred spontaneously, while 10 women were bilaterally ovariectomized. Randomly, the subjects were treated with Estraderm TTS 50 (no. 8) or with Gelestra (no. 14). The pharmacokinetic study of the drugs was performed at the seventh, ninth and 14th day in Gelestra treated women and at the first, third and second day in Estraderm TTS 50 treated women. In fact, the seventh, ninth and 14th day of percutaneous treatment corresponds to the first, third and second day of application of the transdermal system application. Blood samples were taken by each subject at baseline and 1, 2, 3, 4, 8, 12 and 24 h after the gel or transdermal system application. In almost all samples the level of E(2) and estrone (E(1)) were evaluated. Statistical analysis was performed by comparing the two groups of treatment. The following parameters were assessed: mean E(2) and E(1) concentrations, E(2) peak serum concentration within interval from 0 to 72 h (C(max)), E(2) trough concentration within interval from 0 to 72 h (C(min)), area under the E(2) time concentration curve in the interval from 0 to 72 h (AUC((0-72))), the average E(2) concentration during the measurement interval, calculated by dividing AUC((0-72)) by 72 h (C(av)), E(1)/E(2) ratio, and percentage fluctuation (%Fluct) which is equal to 100 (C(max)-C(min)/C(max)). there was no significant difference in E(2) C(av) between the two treatments. However, significant differences in favour to the gel on the first day (first h) and on third day (72nd h) and in favour to the patch at the second day (48th h) were detected. C

  18. Characterization of the uptake of 16 alpha-([18F]fluoro)-17 beta-estradiol in DMBA-induced mammary tumors.

    PubMed

    Mathias, C J; Welch, M J; Katzenellenbogen, J A; Brodack, J W; Kilbourn, M R; Carlson, K E; Kiesewetter, D O

    1987-01-01

    In order to investigate possible correlations between the uptake of 16 alpha-([18F]fluoro)-17 beta-estradiol (18F-ES) by 7,12-dimethylbenz(a) anthracene (DMBA)-induced tumors in rats and the estrogen receptor (ER) content of these tumors, a comprehensive study was performed in which the tissue distribution of 18F-ES was measured in tumor-bearing rats, together with simultaneous measurements of blood volume (by technetium-labeled red blood cells) and blood flow (by iodoantipyrine infusion). In addition, the time course of 18F-ES metabolism and the tissue distribution of the metabolites was studied. Metabolism of 18F-ES is very rapid, and after 2 h, most of the activity in blood and nontarget tissues is due to metabolites; target tissue activity, however, is due mainly to unmetabolized compound. Most of the circulating activity, both 18F-ES and its metabolites, is strongly associated with macromolecules or cells, and while the metabolites are not taken up selectively by target tissues, they do enter nontarget tissues. Tumor blood volume and blood flow vary widely, but not in a way that appears related to tumor necrosis. The uptake of 18F-ES by the uterus and DMBA-induced mammary tumors of adult rats reaches maximum levels (ca 0.35 and 0.10% I.D./g X kg, respectively) at early times (0-1 h), and drops slowly thereafter. The uterus to nontarget or tumour to nontarget tissue ratios, however, start low and continue to increase, reaching maximum levels (ca 20 and 15, respectively) at 2-3 h. There does not, however, appear to be a simple relationship between tumor uptake (either as % I.D./g X kg or tumor to nontarget ratio) measured at a single 3 h time point and tumor ER content, even considering differences in tumor blood flow. This suggests that an estimation of tumor ER content will require the application of more complex pharmacodynamic models that involve the measurement of the complete profile of receptor lignad uptake, retention, and washout from target to

  19. Effects of 17beta-estradiol and testosterone on hepatic mRNA/protein levels and catalytic activities of CYP2M1, CYP2K1, and CYP3A27 in rainbow trout (Oncorhynchus mykiss).

    PubMed

    Buhler, D R; Miranda, C L; Henderson, M C; Yang, Y H; Lee, S J; Wang-Buhler, J L

    2000-10-15

    There is growing concern that exposure to chemicals in the environment can disrupt the endocrine systems of wildlife and humans, causing reproductive problems or other adverse effects. The expression of many cytochrome P450s (CYPs) is under hormonal control, hence, levels of these enzymes can be affected by exposure to endocrine-disrupting chemicals. Previous research has reported that treatment of fish and other animals with the estrogenic and androgenic hormones 17beta-estradiol (E2) and testosterone (T) alters the P450 content or enzyme activities in the treated animals. However, the results of many of these studies are either incomplete or in disagreement and in most cases the effect on specific P450 forms has not been determined. Therefore, to better understand the effects of gonadal hormones on the expression of P450s and their associated enzyme activities, it was of interest to undertake a comprehensive investigation of the transcriptional and translational expression of three constitutive hepatic P450s in the rainbow trout (Oncorhynchus mykiss) following hormone exposure. Accordingly, juvenile trout were injected intraperitoneally with propylene glycol vehicle and the most active estrogenic and androgenic hormones E2 (3 mg/kg) or T (3 mg/kg) on days 1, 4, 7, 13, and 15 and euthanized on day 19. After treatment with E2, hepatic microsomes showed significantly lower levels (percentage of control) in total P450 contents (52%), lauric acid hydroxylase (32%), and 6beta-progesterone hydroxylase activities (27%), [(3)H]aflatoxin-DNA binding (31%), and the protein levels of individual cytochrome P450s (CYPs) LMC1 (CYP2M1), LMC2, (CYP2K1), and LMC5 (CYP3A27) (average for three isoforms a reduction to 29% of control values) with only minor differences between sexes. Treatment with T had either no effect or resulted in small increases in total P450 in males (42%), in lauric acid hydroxylase in females (24%), and in 6beta-progesterone hydroxylase activity in males (21

  20. In vitro antiestrogenic effects of aryl methyl sulfone metabolites of polychlorinated biphenyls and 2,2-bis(4-chlorophenyl)-1,1-dichloroethene on 17beta-estradiol-induced gene expression in several bioassay systems.

    PubMed

    Letcher, Robert J; Lemmen, Josephine G; van der Burg, Bart; Brouwer, Abraham; Bergman, Ake; Giesy, John P; van den Berg, Martin

    2002-10-01

    Methylsulfonyl (MeSO(2)) metabolites of polychlorinated biphenyls (PCBs) and 2,2-bis(4-chlorophenyl)-1,1-dichloroethene (4,4'-DDE), itself a metabolite of the insecticide 4,4'-DDT, are emerging as a major class of contaminants in the tissues of wildlife and humans. We investigated the antiestrogenic capacity and potencies of 3'- and 4'-MeSO(2)-2,2',4,5,5'-pentachlorobiphenyl (CB101) and -2,2',4,5'-tetrachlorobiphenyl (CB49), which are among the most environmentally persistent MeSO(2)-PCBs, and 3-MeSO(2)-4,4'-DDE on estrogen receptor (ER)-dependent gene expression in four cell-based bioassay systems. Congener- and concentration-dependent antagonism of 17beta-estradiol (E2)-induced gene expression, rather than induction of ER-dependent gene expression, was observed for the MeSO(2)-PCBs on lucifierase activity in stably transfected human breast adenocarcinoma T47D cells (ER-CALUX) and vitellogenin (vtg) production in primary hepatocytes from male carp fish (Cyprinus carpio) (CARP-HEP/vtg). 4'-MeSO(2)-CB101 and -CB49 had the highest antagonistic potency (i.e., maximum inhibition of about 70%, LOECs of 1.0 microM and 2.5 microM), whereas 3'-MeSO(2)-CB101 and -CB49 were less antagonistic; the precursor CB101 and MeSO(2)-PCB analog MeSO(2)-2,5-dichlorobenzene had no effect. Relative to the 4-MeSO(2)-PCBs, tamoxifen (IC(50), 0.06 microM and 0.7 microM) was about 40 and 7 times more potent in the ER-CALUX and CARP-HEP/vtg assays, respectively. Congener- and concentration-dependent effects on aryl hydrocarbon receptor-mediated induction of EROD activity (carp hepatocytes), luciferase expression (H4IIE rat hepatoma [H4IIE.luc] cell line), or cell viability were not observed. 3-MeSO(2)-4,4'-DDE was neither estrogenic nor antiestrogenic in either of the bioassays. Inhibitory trends for the MeSO(2)-PCBs in a bioassay based on stably transfected human embryonic kidney cell (HEK293-ERalpha-ERE) were similar to the ER-CALUX and CARP-HEP/vtg bioassays, whereas the antagonism was

  1. Mitogenic estrogen metabolites alter the expression of 17beta-estradiol-regulated proteins including heat shock proteins in human MCF-7 breast cancer cells.

    PubMed

    Kim, Seong Hwan; Lee, Su-Ui; Kim, Myung Hee; Kim, Bum Tae; Min, Yong Ki

    2005-12-31

    Estrogen metabolites are carcinogenic. The comparative mitogenic activities of 17b-estradiol (E2) and four metabolites, 2-hydroxyestradiol (2-OHE2), 4-hydroxyestradiol (4-OHE2), 16a-hydroxyestrone (16a-OHE1) and 2-methoxyestradiol (2-ME), were determined in estrogen receptor(ER)-positive MCF-7 human breast cancer cells. Each of the E2 metabolites caused proliferation of the MCF-7 cells, but only E2 and 16a-OHE1 induced a greater than 20-fold increases in transcripts of the progesterone receptor (PR) gene, a classical ER-mediated gene. This suggests that the mitogenic action of E2 and 16a-OHE1 could result from their effects on gene expression via the ER. E2 metabolites altered the expression of E2-regulated proteins including heat shock proteins (Hsps). 16a-OHE1 and 2-ME as well as E2 increased levels of Hsp56, Hsp60, Hsp90a and Hsp110 transcripts, and the patterns of these inductions resembled that of PR. Hsp56 and Hsp60 protein levels were increased by all the E2 metabolites. Levels of the transcripts of 3 E2-upregulated proteins (XTP3-transactivated protein A, protein disulfide isomerase-associated 4 protein and stathmin 1) and an E2-downregulated protein (aminoacylase 1) were also affected by the E2 metabolites. These results suggest that the altered expression of Hsps (especially Hsp56 and Hsp60) by E2 metabolites such as E2, 16a-OHE1 and 2-ME could be closely linked to their mitogenic action.

  2. Divergent effects of 17-{beta}-estradiol on human vascular smooth muscle and endothelial cell function diminishes TNF-{alpha}-induced neointima formation

    SciTech Connect

    Nintasen, Rungrat; Riches, Kirsten; Mughal, Romana S.; Viriyavejakul, Parnpen; Chaisri, Urai; Maneerat, Yaowapa; Turner, Neil A.; Porter, Karen E.

    2012-04-20

    Highlights: Black-Right-Pointing-Pointer TNF-{alpha} augments neointimal hyperplasia in human saphenous vein. Black-Right-Pointing-Pointer TNF-{alpha} induces detrimental effects on endothelial and smooth muscle cell function. Black-Right-Pointing-Pointer Estradiol exerts modulatory effects on TNF-induced vascular cell functions. Black-Right-Pointing-Pointer The modulatory effects of estradiol are discriminatory and cell-type specific. -- Abstract: Coronary heart disease (CHD) is a condition characterized by increased levels of proinflammatory cytokines, including tumor necrosis factor-{alpha} (TNF-{alpha}). TNF-{alpha} can induce vascular endothelial cell (EC) and smooth muscle cell (SMC) dysfunction, central events in development of neointimal lesions. The reduced incidence of CHD in young women is believed to be due to the protective effects of estradiol (E2). We therefore investigated the effects of TNF-{alpha} on human neointima formation and SMC/EC functions and any modulatory effects of E2. Saphenous vein (SV) segments were cultured in the presence of TNF-{alpha} (10 ng/ml), E2 (2.5 nM) or both in combination. Neointimal thickening was augmented by incubation with TNF-{alpha}, an effect that was abolished by co-culture with E2. TNF-{alpha} increased SV-SMC proliferation in a concentration-dependent manner that was optimal at 10 ng/ml (1.5-fold increase), and abolished by E2 at all concentrations studied (1-50 nM). Surprisingly, E2 itself at low concentrations (1 and 5 nM) stimulated SV-SMC proliferation to a level comparable to that of TNF-{alpha} alone. SV-EC migration was significantly impaired by TNF-{alpha} (42% of control), and co-culture with E2 partially restored the ability of SV-EC to migrate and repair the wound. In contrast, TNF-{alpha} increased SV-SMC migration by 1.7-fold, an effect that was completely reversed by co-incubation with E2. Finally, TNF-{alpha} potently induced ICAM-1 and VCAM-1 expression in both SV-EC and SV-SMC. However there

  3. Changes in hypothalamic monoamine oxidase activity in relation to 17 beta-estradiol and clomiphene citrate treatments in the teleost Channa punctatus during three seasons.

    PubMed

    Khan, I A; Joy, K P

    1991-03-01

    Hypothalamic monoamine oxidase (MAO) activity displayed biphasic responses to administration of estradiol-17 beta (E2) depending on season. Lower doses of 0.05 and 0.10 microgram/g BW of E2 had enhanced enzyme activity and higher doses (0.5 and 1.0 microgram/g BW) depressed it significantly in preparatory season. In prespawning phase, the lowest dose of 0.05 microgram/g BW of E2 was stimulatory and the higher doses were inhibitory to MAO activity. In postspawning season, lower doses (0.05 and 0.10 microgram/g BW) of E2 failed to elicit any significant change in enzyme activity whereas the higher doses (0.5 and 1.0 microgram/g BW) elevated it significantly. Administration of clomid (5, 10, and 20 micrograms/g BW) inhibited MAO activity in a dose-dependent manner during all the three seasons. The results show that E2 may participate in feedback control of gonadotropin secretion by modifying monoaminergic activity at the level of oxidative deamination by MAO.

  4. Randomized, double-masked, 2-year comparison of tibolone with 17beta-estradiol and norethindrone acetate in preventing postmenopausal bone loss.

    PubMed

    Roux, C; Pelissier, C; Fechtenbaum, J; Loiseau-Peres, S; Benhamou, C L

    2002-03-01

    In this 2-year, randomized study, we compared the efficacy and tolerability of tibolone 2.5 mg (n = 75), tibolone 1.25 mg (n = 76) and estradiol 2 mg plus norethindrone acetate 1 mg (E2/NETA: n = 74) for preventing bone loss in postmenopausal women. Bone mineral density (BMD), measured by dual-energy X-ray absorptiometry, and bone remodeling markers were assessed every 6 months. Side-effects were assessed quarterly. After 24 months, the mean increase (+/- SD) in lumbar spine BMD from baseline was 3.6% +/- 2.9%, 1.9% +/- 3.5% and 6.8% +/- 4.5% in the tibolone 2.5 mg, tibolone 1.25 mg and E2/NETA groups, respectively. All pairwise differences were significant. The proportion of responders (women with a change from baseline in lumbar spine BMD of > or = -2% after 2 years) was 95.7%, 89.0% and 98.5% with tibolone 2.5 mg, tibolone 1.25 mg and E2/NETA, respectively. Similar results were obtained for femoral BMD, although the difference between tibolone 2.5 mg and E2/NETA was not significant at 24 months. Decreases in bone remodeling markers were similar in the three groups. Vaginal bleeding was more common in the E2/ NETA group (33.8%) than with tibolone 2.5 mg (12.0%) or tibolone 1.25 mg (9.2%), as was breast pain (23.0%, 2.7% and 2.6%, respectively). Each treatment effectively prevented bone loss. Overall, tolerability of tibolone was better than with E2/NETA, because of less frequent vaginal bleeding and breast pain. This may promote long-term adherence.

  5. High dose 17 beta-estradiol and the alpha-estrogen agonist PPT trigger apoptosis in human adrenal carcinoma cells but the beta-estrogen agonist DPN does not.

    PubMed

    Prieto, L M; Brown, J W; Perez-Stable, C; Fishman, L M

    2008-05-01

    Previous studies have shown that high dose 17beta-estradiol (10 (-5) M) has a G2/M blocking effect in SW-13 human adrenal carcinoma cultures and strongly enhances apoptosis. To examine the differential effects of estrogen alpha and beta-receptors in this system, we incubated SW-13 cells with specific alpha- and beta-estrogen receptor agonists, PPT [4,4',4''-(propyl-[ (1)H]-pyrazole-1,3,5-triyl) trisphenol] and DPN [2,3-bis (4-hydroxyphenyl) propionitrile], respectively (each at 10 (-5) M). Flow cytometry was used to analyze the percentages of cells in various phases of the cell cycle [sub-G1 (apoptosis), G1, S, and G2/M] in each experimental condition. Exposure to 17 beta-estradiol for 48 hours increased apoptosis more than 5-fold (from 3.6+/-0.5 to 20+/-2.2% of cells; p<0.01). The alpha-estrogen agonist PPT had a similar effect, increasing apoptosis to 22+/-1.7% (p<0.01), but the beta-agonist DPN caused no change (3.6+/-0.5 vs. 3.9+/-0.8%). While estrogen and the alpha-estrogen agonist decrease apoptosis in this system, both of these compounds decreased the percentage of cells in G1 (from 59+/-1.4% for control to 34+/-2.3% for estrogen and 40+/-2.0% for PPT; p<0.01 for both agents relative to control); the beta-agonist again had no effect. Estrogen was also found to block the cell cycle in G2/M, increasing it from 15+/-0.4 to 21+/-1.0% of cells (p<0.01), but neither the alpha- nor beta-estrogen agonists had any effect at this point in the cell cycle, indicating that the influence of estrogen was not likely to be either alpha- or beta-receptor mediated. There was no apparent effect of any of these agents on DNA synthesis, as indicated by unchanged percentages of cells in S phase. These studies suggest that induction of apoptosis by estrogen in SW-13 human adrenal cortical carcinoma cultures is mediated by the alpha-receptor, but the G2/M blocking effect of estrogen is not likely to be related to either alpha or beta mechanisms.

  6. An inter-laboratory study on the variability in measured concentrations of 17Beta-estradiol, testosterone and 11-ketotestosterone in white sucker: implications and recommendations

    EPA Science Inventory

    Endocrine-disrupting chemicals (EDCs) are exogenous substances that can lead to impacts on the reproduction of fish sometimes by altering circulating concentrations of 17â-estradiol (E2), testosterone (T) and 11-ketotestosterone (11-KT). Common methods to measure steroids in pla...

  7. An inter-laboratory study on the variability in measured concentrations of 17Beta-estradiol, testosterone and 11-ketotestosterone in white sucker: implications and recommendations

    EPA Science Inventory

    Endocrine-disrupting chemicals (EDCs) are exogenous substances that can lead to impacts on the reproduction of fish sometimes by altering circulating concentrations of 17â-estradiol (E2), testosterone (T) and 11-ketotestosterone (11-KT). Common methods to measure steroids in pla...

  8. Inhibitory effects of Hochu-ekki-to on endometrial carcinogenesis induced by N-methyl-N-nitrosourea and 17beta-estradiol in mice.

    PubMed

    Onogi, Kyoko; Niwa, Kenji; Tang, Liulin; Yun, Wu; Mori, Hideki; Tamaya, Teruhiko

    2006-12-01

    An evaluation of the effects of a traditional Chinese herbal medicine, Hochu-ekki-to (Bu-zong-yi-qi-tang) on endometrial carcinogenesis was performed in experiments with female mice. In the short-term experiment, dietary exposure of Hochu-ekki-to (0.2% for 2 weeks) decreased the estradiol-17beta (E2)-stimulated expression levels of c-jun (P<0.001), tumor necrosis factor (TNF)-alpha (P<0.005), estrogen receptors (ER)-alpha (P<0.001) and ER-beta (P<0.005), as determined by reverse transcription-polymerase chain reaction and a Southern blot analysis in the uteri of the ovarectomized mice. In the long-term experiment, the mice were given N-methyl-N-nitrosourea (MNU) solution (1 mg/100 g body weight) and normal saline (as controls) into their left and right uterine corpora, respectively, and then were divided into four groups. Group 1 (25 mice) was given a diet with Hochu-ekki-to and 5 ppm E2. Group 2 (25 mice) was given a diet with E2 alone. Group 3 (25 mice) was given a diet with Hochu-ekki-to alone. Group 4 (25 mice) was kept on the basal diet alone and treated as a control. The incidence of uterine endometrial cancer in the group with Hochu-ekki-to treatment was substantially lower than of the control group. The inhibitory effect of Hochu-ekki-to on endometrial carcinogenesis is thus suggested to decrease the expressions of c-jun, TNF-alpha, ER-alpha and -beta.

  9. Effects of levonorgestrel, medroxyprogesterone acetate, norethindrone, and 17beta-estradiol on vascular endothelial growth factor isomers 121 and 165 in Ishikawa cells.

    PubMed

    Archer, David F; Navarro, Francisco J; Leslie, Susan; Mirkin, Sebastian

    2004-01-01

    To determine the effect of 17beta-E(2), levonorgestrel, medroxyprogesterone acetate, and norethindrone on the expression of vascular endothelial growth factor (VEGF) isoforms 121 and 165 in Ishikawa cells in vitro. Prospective basic research study. Basic research laboratory. None. Ishikawa cells were cultured in vitro. After 24 hours' incubation in serum-free media, 1.0, 0.1, and 0.01 microM concentrations of E(2), levonorgestrel, medroxyprogesterone acetate, and norethindrone were added for a further 24 hours of incubation. Isolation and identification of VEGF isoforms 121 and 165 using semiquantitative polymerase chain reaction, gel electrophoresis, with beta-actin as an internal control. Estradiol stimulated VEGF isoforms 121 and 165. The progestins studied increased mRNA for VEGF isoforms 121 and 165 at all doses. Medroxyprogesterone acetate resulted in the greatest increase in both VEGF 121 and 165 compared with norethindrone and levonorgestrel. Estradiol and progestins increased VEGF 121 and 165 isoform mRNA in Ishikawa cells in vitro. We hypothesize that differences in VEGF expression may be associated with the irregular bleeding during progestin use in clinical situations.

  10. Environmental Technology Verification Report for Abraxis 17β-Estradiol (E2) Magnetic Particle Enzyme-Linked Immunosorbent Assay (ELISA) Test Kits

    EPA Science Inventory

    The EPA's National Risk Management Research Laboratory (NRMRL) and its verification organization partner, Battelle, operate the Advanced Monitoring Systems (AMS) Center under ETV. The AMS Center recently evaluated the performance of the Abraxis 17(beta)-estradiol (E2) magnetic p...

  11. Reconnaissance of 17 beta-estradiol, 11-ketotestosterone, vitellogenin, and gonad histopathology in common carp of United States streams; potential for contaminant-induced endocrine disruption

    USGS Publications Warehouse

    Goodbred, Steven L.; Gilliom, Robert J.; Gross, Timothy S.; Denslow, Nancy P.; Bryant, Wade B.; Schoeb, Trenton R.

    1997-01-01

    A reconnaissance of sex steroid hormones and other biomarkers in common carp was used to assess whether endocrine disruption may be occurring in fish in United States streams, to evaluate relations between endocrine disruption and contaminant levels, and to determine requirements for further studies. 17?-estradiol, 11-ketotestosterone, vitellogenin, and gonadal histopathology were measured in adult carp (usually 10--15 for each sex) at 25 sites (647 fish), representing a wide range of environmental settings typical of major regions of the nation. Fish were collected during August--December 1994, a period of gonadal maturation after spawning. Contaminants evaluated were organochlorine pesticides and polychlorinated biphenyls in tissue; phthalates, phenols, and polycyclic aromatic hydrocarbons in bed sediment; and dissolved pesticides in water. Mean site concentrations of steroid hormones spanned two orders of magnitude for both sexes. No significant regional differences in steroid hormones were detected for males, but females from the Northern and Southern Midcontinent were significantly different from other regions of the country in one or both hormones. Within all regions there were significant differences between sites in one or both hormones for both sexes. Most correlation coefficients between biomarkers and contaminants were negative. Contaminants that had significant (a=0.05) correlations with biomarkers were organochlorine pesticides, phenols, and dissolved pesticides. The strongest pattern common to both males and females was a negative correlation between the hormone ratio (E2/11-KT) and dissolved pesticides. The significant site-to-site differences in biomarkers, and the presence of significant correlations between biomarkers and contaminants, are evidence that fish in some streams may be experiencing endocrine disruption. Improved information is needed to evaluate whether endocrine disruption is actually occurring and if there are reproductive effects on

  12. Land-cover effects on the fate and transport of surface-applied antibiotics and 17-beta-estradiol on a sandy outwash plain, Anoka County, Minnesota, 2008–09

    USGS Publications Warehouse

    Trost, Jared J.; Kiesling, Richard L.; Erickson, Melinda L.; Rose, Peter J.; Elliott, Sarah M.

    2013-01-01

    A plot-scale field experiment on a sandy outwash plain in Anoka County in east-central Minnesota was used to investigate the fate and transport of two antibiotics, sulfamethazine (SMZ) and sulfamethoxazole (SMX), and a hormone, 17-beta-estradiol (17BE), in four land-cover types: bare soil, corn, hay, and prairie. The SMZ, SMX, and 17BE were applied to the surface of five plots of each land-cover type in May 2008 and again in April 2009. The cumulative application rate was 16.8 milligrams per square meter (mg/m2) for each antibiotic and 0.6 mg/m2 for 17BE. Concentrations of each chemical in plant-tissue, soil, soil-water, and groundwater samples were determined by using enzyme-linked immunosorbent assay (ELISA) kits. Soil-water and groundwater sampling events were scheduled to capture the transport of SMZ, SMX, and 17BE during two growing seasons. Soil and plant-tissue sampling events were scheduled to identify the fate of the parent chemicals of SMZ, SMX, and 17BE in these matrices after two chemical applications. Areal concentrations (mg/m2) of SMZ and SMX in soil tended to decrease in prairie plots in the 8 weeks after the second chemical application, from April 2009 to June 2009, but not in other land-cover types. During these same 8 weeks, prairie plots produced more aboveground biomass and had extracted more water from the upper 125 centimeters of the soil profile compared to all other land-cover types. Areal concentrations of SMZ and SMX in prairie plant tissue did not explain the temporal changes in areal concentrations of these chemicals in soil. The areal concentrations of SMZ and SMX in the aboveground plant tissues in June 2009 and August 2009 were much lower, generally two to three orders of magnitude, than the areal concentrations of these chemicals in soil. Pooling all treatment plot data, the median areal concentration of SMZ and SMX in plant tissues was 0.01 and 0.10 percent of the applied chemical mass compared to 22 and 12 percent in soil

  13. Water-compatible magnetic imprinted nanoparticles served as solid-phase extraction sorbents for selective determination of trace 17beta-estradiol in environmental water samples by liquid chromatography.

    PubMed

    Hao, Yi; Gao, Ruixia; Shi, Lu; Liu, Dechun; Tang, Yuhai; Guo, Zengjun

    2015-05-29

    Endocrine disrupting compounds (EDCs) are a potential risk for wildlife and humans for their existence in water. The efficient extraction and clean-up steps are required before detection of low concentration levels of EDCs. In this work, a novel water-compatible magnetic molecularly imprinted nanoparticles is synthesized for the selective extraction of 17β-estradiol (E2) in environmental water samples. The preparation is carried out by introducing aldehyde groups to the surface of amino-functionalized magnetic nanoparticles through a simple one-step modification, followed by copolymerization of functional monomer gelatin and template E2 via surface imprinting technique. The gelatin with abundant active groups could not only act as functional monomer reacting with template, but also assemble covalently at the surface of magnetic nanoparticles. At the same time, gelatin would improve the water-compatibility of imprinted materials for attaining high extraction efficiency. To obtain high imprinting effect, the preparation conditions are optimized in detail using Central composite design-response surface methodology. The resultant polymers have uniform spherical shape with a shell thickness of about 8nm, stable crystalline form, and super-paramagnetic property. Meanwhile, the obtained polymers have high capacity of 12.87mgg(-1) and satisfactory selectivity to template molecule. To testify the feasibility of the magnetic imprinted polymers in sample pretreatment, a method for determination of trace E2 in environmental water samples was set up by combination of solid-phase extraction (SPE) using the prepared polymers as sorbents and HPLC for rapid isolation and determination of E2. The limit of detection of proposed method is 0.04ngmL(-1), the intra- and inter-day relative standard deviations (RSDs) are less than 4.6% and 5.7%, respectively. The recoveries of E2 from environmental water samples are in the range from 88.3% to 99.1% with the RSDs less than 7.2%. Copyright

  14. Genetic mapping of Eutr1, a locus controlling E2-induced pyometritis in the Brown Norway rat, to RNO5.

    PubMed

    Gould, Karen A; Pandey, Jyotsna; Lachel, Cynthia M; Murrin, Clare R; Flood, Lisa A; Pennington, Karen L; Schaffer, Beverly S; Tochacek, Martin; McComb, Rodney D; Meza, Jane L; Wendell, Douglas L; Shull, James D

    2005-11-01

    In certain rat strains, chronic estrogen administration can lead to pyometritis, an inflammation of the uterus accompanied by infection and the accumulation of intraluminal pus. In this article, we report that the Brown Norway (BN) rat is highly susceptible to pyometritis induced by 17beta-estradiol (E2). The susceptibility of the BN rat to E2-induced pyometritis appears to segregate as a recessive trait in crosses to the resistant August x Copenhagen Irish (ACI) strain. In a (BN x ACI)F(2) population, we find strong evidence for a major genetic determinant of susceptibility to E2-induced pyometritis on rat chromosome 5 (RNO5). Our data are most consistent with a model in which the BN allele of this locus, designated Eutr1 (Estrogen-induced uterine response 1), acts in an incompletely dominant manner to control E2-induced pyometritis. Furthermore, we have confirmed the contribution of Eutr1 to E2-induced uterine pyometritis using an RNO5 congenic rat strain. In addition to Eutr1, we obtained evidence suggestive of linkage for five additional loci on RNO2, 4, 11, 17, and X that control susceptibility to E2-induced pyometritis in the (BN x ACI)F(2) population.

  15. Ghrelin plasmatic levels in patients with fibromyalgia.

    PubMed

    Otero, Miguel; Nogueiras, Ruben; Lago, Francisca; Meijide, Juan; Amarelo, Juan; Mera, Antonio; Gomez-Reino, Juan; Gualillo, Oreste

    2005-01-01

    Ghrelin is a recently discovered 28 amino acid peptide that regulates GH secretion and energy homeostasis. In fibromyalgia (FM) there are alterations in the pituitary-hypothalamic axis, particularly in the growth hormone (GH) secretion pattern. Whether this anomalous secretion of GH pertains to abnormal levels of ghrelin is still unknown. The purpose of this study was to investigate plasma ghrelin levels in patients with fibromyalgia (FM) compared with healthy controls. Plasmatic ghrelin concentrations were determined by a double antibody radioimmunoassay in 19 patients with FM and 14 healthy controls. Compared with controls, patients with FM did not show any significant differences of ghrelin plasmatic levels. In conclusion, FM is not associated with deviation in ghrelin concentrations. Existing alterations in FM with respect to GH are unlikely due to circulating ghrelin.

  16. 17beta-Estradiol inhibits cytokine induction of the human E-selectin promoter.

    PubMed

    Tyree, Curtis M; Zou, Aihua; Allegretto, Elizabeth A

    2002-03-01

    Estradiol has been shown to decrease levels of the cell adhesion molecule E-selectin in cultured cells and in women on hormone replacement therapy. We set out to determine if the mechanism of estradiol action on E-selectin is at the level of its promoter. It was found that estradiol repressed the cytokine-stimulated induction of luciferase activity driven by the human E-selectin promoter in a reporter plasmid (hE-sel-LUC) in co-transfected human hepatoma cells (Hep G2) and human umbilical cord endothelial cells (ECV-304). Repression by estradiol was dependent on the presence of transfected estrogen receptor (ER) alpha or beta expression vectors. The ER antagonist ICI-182,780 blocked the repression by estradiol, confirming the receptor-dependence of the effect. The intact DNA-binding domain of ERalpha was required for estradiol repression of the cytokine-induced stimulation of the promoter in each cell line as demonstrated by the inability of an ER construct with two point mutations in the DNA-binding domain to inhibit reporter activity. Mutation of the NFK-B site at -94 to -85 within the E-selectin promoter led to less stimulation of hE-sel-LUC by interleukin one beta (IL-1beta). Estradiol did not inhibit this IL-1beta stimulated luciferase activity, indicating that the NFK-B site is necessary for ER-mediated inhibition of this promoter. Mutation of the AP-1 site at -500 to -494 within the E-selectin promoter had no effect on the ability of IL-1beta to stimulate its transcription, and estradiol repressed this activation in an ER-dependent manner with identical efficacy and potency in comparison with the wild-type promoter. Therefore, the E-selectin promoter is down-regulated by estradiol working through either ERalpha or ERbeta and requires the NFK-B site at -94 to -85 within the promoter.

  17. Lipocalin 2: a "sexy" adipokine that regulates 17Beta-estradiol and obesity

    USDA-ARS?s Scientific Manuscript database

    In this article we review the findings of Guo et. al. (Endocrinology, 153: 1183-1193) that the protein, Lipocalin 2 is more highly expressed in subcutaneous adipose tissue than in gondal tissue of female mice. Of particular interest is that the paper by Guo et. al. observed that ablation of the Lip...

  18. Assessing the effects of exposure timing on biomarker expression using 17beta-estradiol

    EPA Science Inventory

    Temporal and spatial variability in estrogenicity has been documented for many treated wastewater effluents with the consequences of this variability on the expression of biomarkers of endocrine disruption being largely unknown. Laboratory exposure studies usually utilize constan...

  19. Assessing the effects of exposure timing on biomarker expression using 17beta-estradiol

    EPA Science Inventory

    Temporal and spatial variability in estrogenicity has been documented for many treated wastewater effluents with the consequences of this variability on the expression of biomarkers of endocrine disruption being largely unknown. Laboratory exposure studies usually utilize constan...

  20. 17Beta-Estradiol Inhibits Calcium-Activated Potassium Channel Expressions in Rat Whole Bladder

    PubMed Central

    2016-01-01

    Purpose: To investigate the effect of estrogen on the expression of calcium-activated potassium (KCa) channels in an overactive bladder rat model. To this end, mRNA and protein levels of KCa channel subtypes in the bladder of ovariectomized rats were measured by reverse transcription polymerase chain reaction and western blotting, respectively. Methods: Ten-week-old female Sprague-Dawley rats were divided randomly into 3 groups: sham-operated control group (n=11), ovariectomy group (n=11), and the group treated with estrogen after ovariectomy (n=12). Rats in the last group were subcutaneously injected with 17β-estradiol (50 μg/kg) every other day for 2 weeks, whereas rats in the other 2 groups received vehicle (soybean oil) alone. Two weeks after treatment, the whole bladder was excised for mRNA and protein measurements. Results: Protein levels of the large-conductance KCa (BK) channels in the ovariectomy group were 1.5 folds higher than those in the sham-operated control group. However, the protein levels of the other KCa channel subtypes did not change significantly upon bilateral ovariectomy. Treatment with 17β-estradiol after ovariectomy restored BK channel protein levels to the control value. In contrast, BK channel mRNA levels were not significantly affected by either ovariectomy alone or 17β-estradiol treatment. The small-conductance KCa type 3 channel (SK3) mRNA and protein levels decreased to 75% of control levels upon 17β-estradiol treatment. Conclusions: These results suggest that 17β-estradiol may influence urinary bladder function by modulating BK and SK3 channel expression. PMID:27032553

  1. Sex- and tissue-specific effects of waterborne estrogen on estrogen receptor subtypes and E2-mediated gene expression in the reproductive axis of goldfish.

    PubMed

    Marlatt, Vicki L; Lakoff, Josh; Crump, Kate; Martyniuk, Chris J; Watt, Jennifer; Jewell, Linda; Atkinson, Susanna; Blais, Jules M; Sherry, Jim; Moon, Thomas W; Trudeau, Vance L

    2010-05-01

    This research examined the gene expression profile of three goldfish estrogen receptor (ER) subtypes in multiple tissues in relation to mRNA levels of aromatase B and vitellogenin (VTG) following waterborne estrogen exposures. The protocol consisted of: i) adult male goldfish in late gonadal recrudescence exposed to 1 nM 17beta-estradiol (E2); ii) adult male and female goldfish in early sexual regression exposed to 1 nM E2 for 3, 6, 12 and 24h; and, iii) sexually mature, adult male goldfish exposed to 0.3 nM 17alpha-ethynylestradiol (EE2) for 24h. Liver produced the most consistent response with up-regulation of ERalpha in sexually regressed, mature and recrudescing males and in sexually regressed females. The dose and length of exposure, reproductive state and sex affected the auto-regulation of ERbeta1 by E2. ERbeta2 was not affected in any experiments suggesting it may not be auto-regulated by E2. Aromatase B and VTG gene expression were affected by E2, but also by other experimental conditions. EE2 induced liver ERalpha and VTG mRNA levels indicating that high environmental EE2 levels induce E2-mediated gene expression in a model teleost. These studies reveal a more complicated action of estrogenic compounds that has important implications on estrogenic endocrine disruptors in teleosts. Copyright 2010 Elsevier Inc. All rights reserved.

  2. The effect of 17 beta-estradiol on cholesterol in human macrophages is influenced by the lipoprotein milieu

    USDA-ARS?s Scientific Manuscript database

    Estrogen and testosterone are thought to modulate coronary heart disease (CHD) risk. To examine how these hormones affect human macrophage cholesterol transport, a key factor in atherogenesis, we obtained monocytes from healthy male and postmenopausal female donors (age 50-70 y). Cells were allowe...

  3. Acceleration of adenovirus replication and increased virion production by treatment with the steroid hormone 17 beta-estradiol.

    PubMed

    James, C B; Vanderpool, E A; Roane, P

    1992-01-01

    We report here that concentration of an estrogen known to promote enhanced transformation and to increase oncogenicity of rat embryo cells, accelerate the production and increase the yield of progeny virions in adenovirus type 12 (Ad 12)-infected HEp-2 cells. Further, measurement of the incorporation of radioactive RNA and DNA precursors indicated that macromolecular synthesis in the estrogen-treated, infected cells was accelerated. Possible explanations for this observation are discussed.

  4. Effects of 17Beta-estradiol on cognitive performance of ovariectomized female rats exposed to 56Fe particles

    USDA-ARS?s Scientific Manuscript database

    On exploratory class missions to other planets astronauts will be exposed to types and doses of radiation (HZE particles) that are not experienced in low earth orbit. While it is likely that the crew will consist of both male and female astronauts, there has been little research on the effects of ...

  5. PROMOTION BY 17BETA-ESTRADIOL AND BETA-HEXACHLOROCYCLOHEXANE OF HEPATOCELLULAR TUMORS IN MEDAKA, ORYZIAS LATIPES. (R825298)

    EPA Science Inventory

    Abstract

    A feature common to many laboratory and field studies with various fish species is a higher prevalence of hepatocellular neoplasia in females than in males. During female sexual maturation, endogenous estrogens stimulate substantial increases in synthetic acti...

  6. PROMOTION BY 17BETA-ESTRADIOL AND BETA-HEXACHLOROCYCLOHEXANE OF HEPATOCELLULAR TUMORS IN MEDAKA, ORYZIAS LATIPES. (R825298)

    EPA Science Inventory

    Abstract

    A feature common to many laboratory and field studies with various fish species is a higher prevalence of hepatocellular neoplasia in females than in males. During female sexual maturation, endogenous estrogens stimulate substantial increases in synthetic acti...

  7. 17beta-estradiol counteracts neuropathic pain: a behavioural, immunohistochemical, and proteomic investigation on sex-related differences in mice

    PubMed Central

    Vacca, Valentina; Marinelli, Sara; Pieroni, Luisa; Urbani, Andrea; Luvisetto, Siro; Pavone, Flaminia

    2016-01-01

    Sex differences play a role in pain sensitivity, efficacy of analgesic drugs and prevalence of neuropathic pain, even if the underlying mechanisms are far from being understood. We demonstrate that male and female mice react differently to structural and functional changes induced by sciatic nerve ligature, used as model of neuropathic pain. Male mice show a gradual decrease of allodynia and a complete recovery while, in females, allodynia and gliosis are still present four months after neuropathy induction. Administration of 17β-estradiol is able to significantly attenuate this difference, reducing allodynia and inducing a complete recovery also in female mice. Parallel to pain attenuation, 17β-estradiol treated-mice show a functional improvement of the injured limb, a faster regenerative process of the peripheral nerve and a decreased neuropathy-induced gliosis. These results indicate beneficial effects of 17β-estradiol on neuropathic pain and neuronal regeneration and focuses on the importance of considering gonadal hormones also in clinical studies. PMID:26742647

  8. 17beta-estradiol counteracts neuropathic pain: a behavioural, immunohistochemical, and proteomic investigation on sex-related differences in mice.

    PubMed

    Vacca, Valentina; Marinelli, Sara; Pieroni, Luisa; Urbani, Andrea; Luvisetto, Siro; Pavone, Flaminia

    2016-01-08

    Sex differences play a role in pain sensitivity, efficacy of analgesic drugs and prevalence of neuropathic pain, even if the underlying mechanisms are far from being understood. We demonstrate that male and female mice react differently to structural and functional changes induced by sciatic nerve ligature, used as model of neuropathic pain. Male mice show a gradual decrease of allodynia and a complete recovery while, in females, allodynia and gliosis are still present four months after neuropathy induction. Administration of 17β-estradiol is able to significantly attenuate this difference, reducing allodynia and inducing a complete recovery also in female mice. Parallel to pain attenuation, 17β-estradiol treated-mice show a functional improvement of the injured limb, a faster regenerative process of the peripheral nerve and a decreased neuropathy-induced gliosis. These results indicate beneficial effects of 17β-estradiol on neuropathic pain and neuronal regeneration and focuses on the importance of considering gonadal hormones also in clinical studies.

  9. Comparative effect of soy protein, soy isoflavones, and 17beta-estradiol on bone metabolism in adult ovariectomized rats.

    PubMed

    Cai, David J; Zhao, Yongdong; Glasier, Jennifer; Cullen, Diane; Barnes, Stephen; Turner, Charles H; Wastney, Meryl; Weaver, Connie M

    2005-05-01

    This study provided a comprehensive investigation on the effect of soy protein and soy isoflavones on both calcium and bone metabolism in virgin adult rats. The measurements included bone histology, calcium kinetic modeling, calcium balance, bone densitometry, and whole body densitometry. Results confirmed the bone-preserving effect of estrogen but did not support a bone-sparing role of soy isoflavones. Several animal and short-term human studies have indicated that soy protein isolate enriched with isoflavones may be used as an alternative therapy to estrogen replacement therapy. However, none of the previous studies have investigated this estrogenic effect on both calcium and bone metabolism in animals or humans, which is essential in ascertaining the mode of action of isoflavones. This study was designed to determine the effects of soy protein versus isoflavones on calcium and bone metabolism in an ovariectomized rat model. Unmated 6-month-old ovariectomized and sham-operated female Sprague-Dawley rats were randomly assigned to nine groups (16 rats/group) and pair-fed soy- or casein-based diets with or without isoflavones for 8 weeks. A reference group was administered estrogen through subcutaneous implants (20-35 pg/liter plasma). Bone densitometry, histomorphometry, and mechanical testing were used to study bone metabolism and quality. Calcium metabolism was studied using calcium tracer balance and kinetics. After ovariectomy, estrogen prevented bone loss in trabecular bone and suppressed formation on both trabecular and cortical bone surfaces. Isoflavones given as enriched soy protein isolate or supplements did not prevent trabecular bone loss. Combining isoflavones with estrogen had no additional benefits over estrogen alone. There were no differences in response to isoflavones caused by protein source. None of the treatments significantly affected either total Ca balance or (45)Ca absorption. However, soy protein showed significant effects on reducing urinary loss of Ca in animals, irrespective of isoflavone level, perhaps because of the lower amount of sulfur-containing amino acids in soy protein. Estrogen, but not isoflavones at the levels tested, suppressed bone remodeling in both trabecular and cortical bone after ovariectomy.

  10. [Plasmatic membrane protein synthesis in cells of the regenerating liver].

    PubMed

    Pospelov, A V; Gorelova, N V

    1978-05-01

    Protein synthesis in the cells of the regenerating rat liver was studied. The rate of 3H-glycine incorporation into the total proteins of the liver, those of microsomal fraction, proteins of hyaloplasm, and plasmatic membrane proteins, soluble and non-soluble in 0.05 M K2CO3, was determined. The rate of 3H-glycine incorporation into soluble proteines of plasma membranes became maximal one hour after partial hepatectomy. The peak of the rate of synthesis of proteins of other fractions fell on the end of the G1-period. A sharp increase of the synthesis rate of plasma membrane proteins seems to be one of the earliest biochemical events in the regenerating liver hepatocytes ready for division.

  11. Estrogen receptor-related receptor alpha mediates up-regulation of aromatase expression by prostaglandin E2 in prostate stromal cells.

    PubMed

    Miao, Lin; Shi, Jiandang; Wang, Chun-Yu; Zhu, Yan; Du, Xiaoling; Jiao, Hongli; Mo, Zengnan; Klocker, Helmut; Lee, Chung; Zhang, Ju

    2010-06-01

    Estrogen receptor-related receptor alpha (ERRalpha) is an orphan member of the nuclear receptor superfamily of transcription factors. ERRalpha is highly expressed in the prostate, especially in prostate stromal cells. However, little is known about the regulation and function of ERRalpha, which may contribute to the progression of prostatic diseases. We previously found that prostaglandin E2 (PGE2) up-regulated the expression of aromatase in prostate stromal cells. Here we show that PGE2 also up-regulates the expression of ERRalpha, which, as a transcription factor, further mediates the regulatory effects of PGE2 on the expression of aromatase. ERRalpha expression was up-regulated by PGE2 in prostate stromal cell line WPMY-1, which was mediated mainly through the protein kinase A signaling pathway by PGE2 receptor EP2. Suppression of ERRalpha activity by chlordane (an antagonist of ERRalpha) or small interfering RNA knockdown of ERRalpha blocked the increase of expression and promoter activity of aromatase induced by PGE2. Overexpression of ERRalpha significantly increased aromatase expression and promoter activity, which were further augmented by PGE2. Chromatin immunoprecipitation assay demonstrated that ERRalpha directly bound to the aromatase promoter in vivo, and PGE2 enhanced the recruitment of ERRalpha and promoted transcriptional regulatory effects on aromatase expression in WPMY-1. 17Beta-estradiol concentration in WPMY-1 medium was up-regulated by ERRalpha expression, and that was further increased by PGE2. Our results provided evidence that ERRalpha contributed to local estrogen production by up-regulating aromatase expression in response to PGE2 and provided further insights into the potential role of ERRalpha in estrogen-related prostatic diseases.

  12. Photodynamic action of chlorin e6 on thymocyte plasmatic and mitochondrial membrane potentials

    NASA Astrophysics Data System (ADS)

    Gyulkhandanyan, Grigor V.

    2005-08-01

    Transmembrane potentials appear to be cell state sensitive characteristics and can give information about cell damage initial stage. Photodynamic action of the photosensitizer chlorin e6 on plasmatic and mitochondrial membrane potentials of the rat thymus lymphocytes was studied using voltage-sensitive dye rhodamine 6G. It has been revealed that mitochondrial membrane potential is more sensitive characteristic of membrane disfunction than plasmatic one at the cell photodamage.

  13. Impact of dose and surface features on plasmatic and liver concentrations of biodegradable polymeric nanocapsules.

    PubMed

    Oliveira, Líliam Teixeira; de Paula, Mônica Auxiliadora; Roatt, Bruno Mendes; Garcia, Giani Martins; Silva, Luan Silvestro Bianchini; Reis, Alexandre Barbosa; de Paula, Carina Silva; Vilela, José Mário Carneiro; Andrade, Margareth Spangler; Pound-Lana, Gwenaelle; Mosqueira, Vanessa Carla Furtado

    2017-07-15

    The effect of polymeric nanocapsule dose on plasmatic and liver concentrations 20min after intravenous administration in mice was evaluated. Nanocapsules were prepared with different polymers, namely, poly(D,L-lactide) (PLA), polyethylene glycol-block-poly(D,L-lactide) (PLA-PEG), and PLA with chitosan (PLA-Cs) and compared with a nanoemulsion. These formulations were labelled with a phthalocyanine dye for fluorescent detection. The nanostructures had narrow size distributions upon separation by asymmetric flow field flow fractionation with static and dynamic light scattering detection, with average hydrodynamic diameters in the 130-300nm range, negative zeta potentials, except PLA-Cs nanocapsules, which had a positive zeta potential. Flow cytometry revealed uptake mostly by monocytes and neutrophils in mice and human blood. PLA nanocapsules and the nanoemulsion showed dose-dependent plasma concentrations, where the percentage of plasmatic fluorescence increased with increasing administered dose. In contrast, PLA-PEG nanocapsules led to a dose-independent plasmatic profile. PLA-Cs nanocapsules showed the lowest plasmatic and liver levels of fluorescence at all administered doses and significant intravenous toxicity in mice. This work demonstrates the importance of considering the nanocarrier dose when evaluating pharmacokinetic and biodistribution data and emphasizes the role of surface features in determining the plasmatic and liver concentrations of a poorly soluble lipophilic encapsulated compound. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. SPE-LC/ESI/MS: a simple and reproducible method for detection and quantification of 17beta-estradiol in aqueous samples

    USDA-ARS?s Scientific Manuscript database

    Steroid estrogens contained in wastewater discharge from sewage treatment plants and agricultural run-off can alter endocrine function in exposed wildlife at part per trillion (ng/L) levels. Detection and quantification of estrogens in the environment at these levels pose numerous analytical challen...

  15. Uterine physiological responses and global gene expression in ovariectomized (ovx) rats treated with soy protein isolate (spi) or 17Beta-estradiol

    USDA-ARS?s Scientific Manuscript database

    Concerns regarding increased endometrial cancer risk have been raised in women who consume soy products as the result of the estrogenicity of phytochemical components such as the isoflavones genistein and daidzein. Female Sprague-Dawley rats (N = 20/group) were fed AIN-93G diets with casein or SPI a...

  16. DNA ARRAYS TO MONITOR GENE EXPRESSION IN RAT BLOOD AND UTERUS FOLLOWING 17-BETA-ESTRADIOL EXPOSURE: BIOMONITORING ENVIRONMENTAL EFFECTS USING SURROGATE TISSUES

    EPA Science Inventory

    DNA arrays to monitor gene expression in rat blood and uterus following 17-b-estradiol exposure - biomonitoring environmental effects using surrogate tissues
    John C. Rockett, Robert J. Kavlock, Christy R. Lambright, Louise G. Parks, Judith E. Schmid, Vickie S. Wilson, Carmen W...

  17. Mammary gland morphology and gene expression differ in female rats treated with 17 beta-estradiol or fed soy protein isolate

    USDA-ARS?s Scientific Manuscript database

    Soy foods have been suggested to have both positive health benefits and potentially adverse effects as a result of their content of phytoestrogens. However, studies on the estrogenicity of soy foods are lacking. Here we directly compared the effects of soy protein isolate (SPI), the protein in soy i...

  18. A Computational Model of the Hypothalamic-pituitary-gonadal Axis in Male Fathead Minnows Exposed to 17 | *alpha* | -ethinylestradiol and 17 | *beta* | -estradiol

    EPA Science Inventory

    Estrogenic chemicals in the aquatic environment have been shown to cause a variety of reproductive anomalies in fish including full sex reversal, intersex, and altered population sex ratios. Two estrogens found in the aquatic environment, 17-ethinylestradiol and 17â-estradiol, h...

  19. Modulation of vitellogenin synthesis through estrogen receptor beta-1 in goldfish (Carassius auratus) juveniles exposed to 17-{beta} estradiol and nonylphenol

    SciTech Connect

    Soverchia, L.; Ruggeri, B.; Palermo, F.; Mosconi, G.; Cardinaletti, G.; Scortichini, G.; Gatti, G.; Polzonetti-Magni, A.M. . E-mail: alberta.polzonetti@unicam.it

    2005-12-15

    Many synthetic chemicals, termed xenoestrogens, have been shown to interact as agonists with the estrogen receptor (ER) to elicit biological responses similar to those of natural hormones. To date, the regulation of vitellogenesis in oviparous vertebrates has been widely used for evaluation of estrogenic effects. Therefore, Carassius auratus juveniles were chosen as a fish model for studying the effects of estradiol-17{beta} and different concentrations (10{sup -6} and 10{sup -7} M) of 4-nonylphenol (4-NP) on the expression of liver ER{beta}-1 subtype; plasma vitellogenin and sex steroids (androgens and estradiol-17{beta}) were also evaluated together with the bioaccumulation process, through mass-spectrometry. C. auratus is a species widespread in the aquatic environment and, on the toxicological point of view, can be considered a good 'sentinel' species. Juveniles of goldfish were maintained in tanks with only tap water or water with different concentrations (10{sup -6} and 10{sup -7} M) of 4-nonylphenol (4-NP), or 10{sup -7} M of estradiol-17{beta}. After 3 weeks of treatment, animals were anesthetized within 5 min after capture, and blood was immediately collected into heparinized syringes by cardiac puncture and stored at -70 deg. C; the gonads were fixed, then frozen and stored at -70 deg. C; the whole fish, liver, and muscle tissues were harvested and immediately stored at -70 deg. C for molecular biology experiments and bioaccumulation measurements. The estrogenic effects of 4-NP were evidenced by the presence of plasma vitellogenin in juveniles exposed both to estradiol-17{beta} and the two doses of 4-NP; moreover, exposure to 4-NP also increased aromatization of androgens, as suggested by decreasing androgens and increasing estradiol-17{beta} plasma levels. The changes of these parameters were in agreement with the increasing transcriptional rate of ER{beta}-1 mRNA in the liver, demonstrating that both estradiol-17{beta} and 4-NP modulate the vitellogenin rate through interaction with the ER{beta}-1 subtype. The present study also suggests that 4-NP at the concentration of 10{sup -6} M bioaccumulates in the liver.

  20. PROMOTION BY 17&BETA;-ESTRADIOL AND &BETA;-HEXACHLOROCYCLOHEXANE OF HEPATOCELLULAR TUMORS IN MEDAKA, ORYZIAS LATIPES. AQUAT. (R828676C002)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  1. 17beta-Estradiol and testosterone in drainage and runoff from poultry litter applications to tilled and no-till crop land under irrigation.

    PubMed

    Jenkins, Michael B; Endale, Dinku M; Schomberg, Harry H; Hartel, Peter G; Cabrera, Miguel L

    2009-06-01

    Thirteen million [corrected] metric tons of poultry litter are produced annually by poultry producers in the U.S. Poultry litter contains the sex hormones estradiol and testosterone, endocrine disruptors that have been detected in surface waters. The objective of this study was to evaluate the potential impact of poultry litter applications on estradiol and testosterone concentrations in subsurface drainage and surface runoff in irrigated crop land under no-till and conventional-till management. We conducted an irrigation study in fall of 2001 and spring of 2002. Four treatments, no-till plus poultry litter, conventional-till plus poultry litter, no-till plus conventional fertilizer, and conventional-till plus conventional fertilizer, were evaluated. Flow-weighted concentration and load ha(-1) of the two hormones were measured in drainage and runoff. Soil concentrations of estradiol and testosterone were measured. Based on comparisons to the conventional fertilizer (and control) treatments, poultry litter did not add to the flow-weighted concentration or load ha(-1) of either estradiol or testosterone in subsurface drainage or surface runoff. Significant differences were, however, observed between tillage treatments: flow-weighted concentrations of estradiol were greater for no-till than conventional-till plots of the June irrigation; and runoff loads of both estradiol and testosterone were less from no-till than conventional-till plots for the November irrigation. Although the differences between no-till and conventional-tillage appeared to affect the hydrologic transport of both hormones, the differences appeared to have inconsequential environmental impact.

  2. DNA ARRAYS TO MONITOR GENE EXPRESSION IN RAT BLOOD AND UTERUS FOLLOWING 17-BETA-ESTRADIOL EXPOSURE: BIOMONITORING ENVIRONMENTAL EFFECTS USING SURROGATE TISSUES

    EPA Science Inventory

    DNA arrays to monitor gene expression in rat blood and uterus following 17-b-estradiol exposure - biomonitoring environmental effects using surrogate tissues
    John C. Rockett, Robert J. Kavlock, Christy R. Lambright, Louise G. Parks, Judith E. Schmid, Vickie S. Wilson, Carmen W...

  3. A Computational Model of the Hypothalamic-pituitary-gonadal Axis in Male Fathead Minnows Exposed to 17 | *alpha* | -ethinylestradiol and 17 | *beta* | -estradiol

    EPA Science Inventory

    Estrogenic chemicals in the aquatic environment have been shown to cause a variety of reproductive anomalies in fish including full sex reversal, intersex, and altered population sex ratios. Two estrogens found in the aquatic environment, 17-ethinylestradiol and 17â-estradiol, h...

  4. DETERMINING THE SENSITIVE DEVELOPMENTAL STAGES OF INTERSEX INDUCTION IN MEDAKA (ORYZIAS LATIPES) EXPOSED TO 17 BETA-ESTRADIOL OR TESTOSTERONE. (R825298)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  5. DETERMINING THE SENSITIVE DEVELOPMENTAL STAGES OF INTERSEX INDUCTION IN MEDAKA (ORYZIAS LATIPES) EXPOSED TO 17 BETA-ESTRADIOL OR TESTOSTERONE. (R825298)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  6. Identification of two Isoforms of Vitelline Envelope Protein as Complementary Biomarkers to Vitellogenin in the Plasma of Rainbow Trout Exposed to 17beta-estradiol

    EPA Science Inventory

    In the present study, protein markers of estrogenic exposure in rainbow trout (Oncorhynchus mykiss) were isolated and identified using innovative sample preparation techniques followed by advanced MS and bioinformatics approaches. Juvenile trout were administered 17ß-estradiol t...

  7. Shear stress and 17beta-estradiol modulate cerebral microvascular endothelial Na-K-Cl cotransporter and Na/H exchanger protein levels.

    PubMed

    Chang, Elaine; O'Donnell, Martha E; Barakat, Abdul I

    2008-01-01

    Ion transporters of blood-brain barrier (BBB) endothelial cells play an important role in regulating the movement of ions between the blood and brain. During ischemic stroke, reduction in cerebral blood flow is accompanied by transport of Na and Cl from the blood into the brain, with consequent brain edema formation. We have shown previously that a BBB Na-K-Cl cotransporter (NKCC) participates in ischemia-induced brain Na and water uptake and that a BBB Na/H exchanger (NHE) may also participate. While the abrupt reduction of blood flow is a prominent component of ischemia, the effects of flow on BBB NKCC and NHE are not known. In the present study, we examined the effects of changes in shear stress on NKCC and NHE protein levels in cerebral microvascular endothelial cells (CMECs). We have shown previously that estradiol attenuates both ischemia-induced cerebral edema and CMEC NKCC activity. Thus, in the present study, we also examined the effects of estradiol on NKCC and NHE protein levels in CMECs. Exposing CMECs to steady shear stress (19 dyn/cm(2)) increased the abundance of both NKCC and NHE. Estradiol abolished the shear stress-induced increase in NHE but not NKCC. Abrupt reduction of shear stress did not alter NKCC or NHE abundance in the absence of estradiol, but it decreased NKCC abundance in estradiol-treated cells. Our results indicate that changes in shear stress modulate BBB NKCC and NHE protein levels. They also support the hypothesis that estradiol attenuates edema formation in ischemic stroke in part by reducing the abundance of BBB NKCC protein.

  8. Effects of 17beta-estradiol and IGF-1 on L-type voltage-activated and stretch-activated calcium currents in cultured rat cortical neurons.

    PubMed

    Sánchez, Julio C; López-Zapata, Diego F; Pinzón, Oscar A

    2014-01-01

    Calcium transport pathways are key factors for understanding how changes in the cytoplasmic calcium concentration are associated with neuroprotection because calcium is involved in the onset of death signaling in neurons. This study characterized the effects of 17β-estradiol and IGF-1 on voltage-activated and stretch-activated calcium channels in rat cultured cortical neurons. The whole-cell patch-clamp technique, using a voltage steps protocol or by applying positive pressure into the micropipette, was used on 7-10 day cultured neurons from a Wistar rat cortex, and pharmacological characterization was performed on these neurons. Both 17β-estradiol and IGF-1 inhibited the currents mediated by L-type voltage-activated calcium channels, although the IGF-1 effects were lower than those of 17β-estradiol. The effect of both hormones together was greater than the sum of the effects of the individual agents. Unlike IGF-1, 17β-estradiol decreased the current mediated by stretch-activated channels. The inhibition of the classical receptors of these hormones did not affect the results. Both hormones regulate voltage-activated calcium channels in a synergistic way, but only 17β-estradiol has an inhibitory effect on stretch-activated calcium channels. These effects are not mediated by classical receptors and may be relevant to the neuroprotective effects of both hormones because they diminish calcium entry into the neuron and decrease the possibility for the onset of apoptotic signaling.

  9. Identification of two Isoforms of Vitelline Envelope Protein as Complementary Biomarkers to Vitellogenin in the Plasma of Rainbow Trout Exposed to 17beta-estradiol

    EPA Science Inventory

    In the present study, protein markers of estrogenic exposure in rainbow trout (Oncorhynchus mykiss) were isolated and identified using innovative sample preparation techniques followed by advanced MS and bioinformatics approaches. Juvenile trout were administered 17ß-estradiol t...

  10. Diagnostic value of the plasmatic ADM level for early ectopic pregnancy.

    PubMed

    Yan, Qi; Lu, Qi; Tao, Yu; Wang, Yu-Dong; Zhao, Wen-Xia

    2015-01-01

    To analyze the plasmatic ADM level in early pregnancy and to investigate the diagnostic value of ADM in early ectopic pregnancy (EP). 70 patients with EP who had menopause for 5~8 weeks were included as study group, while 155 women with normal intrauterine pregnancy were also included as control group. The correlation between ADM level and menopause weeks was statistically analyzed and ROC curve was used to identify the diagnostic value of ADM. (1) In 155 cases of normal intrauterine pregnancy, the plasmatic ADM level was increased with menopause weeks in linear relationship, and the correlation coefficient (R) was 0.991 (P<0.05). In 70 patients with EP, no significant increase was found with menopause weeks and no linear relationship can be found between ADM level and menopause weeks in EP group. The correlation coefficient (R) was 0.744 (P>0.05). (2) The multiple of median of plasmatic ADM level in EP group of menopause for 8 weeks was obviously lower than the intrauterine control group (P<0.01). (3) ROC curve was used to analyze the cut-off value of ADM level in the diagnosis of EP, and the area under the ROC curve was 0.523 (P>0.05) regardless of menopause weeks, however, the area under the ROC curve was 0.702 (P<0.05) at 8 weeks after menopause with sensitivity of 53.50% and specificity of 85.00%. Different from normal intrauterine pregnancy, plasmatic ADM level in early EP was relatively lower and no significant increase was found with menopause weeks; further studies are still needed for plasmatic ADM level as an indicator in the early diagnosis of EP.

  11. Interleukin-6 Plasmatic Levels in Patients with Head Trauma and Intracerebral Hemorrhage

    PubMed Central

    Antunes, Alessandra Armstrong; Sotomaior, Vanessa Santos; Sakamoto, Keyth Suga; de Camargo Neto, Cyro Pereira; Martins, Carolina; Aguiar, Luiz Roberto

    2010-01-01

    The exact role of inflammatory response in hemorrhagic contusions is not fully characterized. The present study quantified IL-6 plasmatic levels in patients with closed head trauma and hemorrhagic contusions during the first 6 to 12 hours postrauma. The association between the plasmatic IL-6 levels, severity of trauma according to the Glasgow Coma Scale, volume of intracerebral hemorrhage and patient's clinical evolution were investigated. Although inflammation is a multifactorial process, a strong correlation between IL-6 levels, volume of traumatic hemorrhage and in-hospital evolution could be observed. A correlation between the IL-6 levels quantified 6 hours postrauma and progression of lesion volume between admission and 12 hours postrauma is suggested. The present study reinforces the importance of IL-6 in influencing the clinical conditions of a patient with cerebral injuries, particularly hemorrhagic contusions. PMID:22028746

  12. Value of plasmatic membrane attack complex as a marker of severity in acute kidney injury.

    PubMed

    Rodríguez, Eva; Riera, Marta; Barrios, Clara; Pascual, Julio

    2014-01-01

    The aim of this study was to determine if complement pathway is activated in AKI; for this purpose, we measured, through ELISA sandwich, the terminal lytic fraction of the complement system, called membrane attack complex (C5b-C9), in AKI patients compared with patients with similar clinical conditions but normal renal function. Our data showed that complement system is activated in AKI. Plasmatic MAC concentrations were significantly higher in AKI patients than in those with normal renal function; this difference is maintained independently of the AKI etiology and is proportional to the severity of AKI, measured by ADQI classification. In addition, we found that plasmatic MAC concentrations were significantly higher in patients who did not recover renal function at time of hospitalization discharge, in patients who died during the acute process, and in patients who need renal replacement therapy during hospitalization, but in this last group, the differences did not reach statistical significance. In conclusion, plasmatic MAC concentration seems valuable as a marker of AKI severity.

  13. Oxidative stress and labile plasmatic iron in anemic patients following blood therapy

    PubMed Central

    Fernandes, Marília Sabo; Rissi, Tatiana Tamborena; Zuravski, Luisa; Mezzomo, Juliana; Vargas, Carmen Regla; Folmer, Vanderlei; Soares, Félix Alexandre Antunes; Manfredini, Vanusa; Ahmed, Mushtaq; Puntel, Robson Luiz

    2014-01-01

    AIM: To determine the plasmatic iron content and evaluate the oxidative stress (OS) markers in subjects receiving blood therapy. METHODS: Thirty-nine individuals with unspecified anemia receiving blood transfusions and 15 healthy subjects were included in the study. Anemic subjects were divided into three subgrouP: (1) those that received up to five blood transfusions (n = 14); (2) those that received from five to ten transfusions (n = 11); and (3) those that received more than ten transfusions (n = 14). Blood samples were collected by venous arm puncture and stored in tubes containing heparin. The plasma and cells were separated by centrifugation and subsequently used for analyses. Statistical analyses were performed using Kruskal-Wallis analysis of variance followed by Dunn’s multiple comparison tests when appropriate. RESULTS: The eletrophoretic hemoglobin profiles of the subjects included in this study indicated that no patients presented with hemoglobinopathy. Labile plasmatic iron, ferritin, protein carbonyl, thiobarbituric acid-reactive substances (TBARS) and dichlorofluorescein diacetate oxidation were significantly higher (P < 0.05), whereas total thiol levels were significantly lower (P < 0.05) in transfused subjects compared to controls. Additionally, the activity of catalase, superoxide dismutase and glutathione peroxidase were significantly lower in the transfused subjects (P < 0.05). Antioxidant enzyme activities and total thiol levels were positively correlated (P < 0.05), and negatively correlated with the levels of protein carbonyl and TBARS (P < 0.05). In contrast, protein carbonyl and TBARS were positively correlated (P < 0.05). Altogether, these data confirm the involvement of OS in patients following therapy with repeated blood transfusions. CONCLUSION: Our data reveal that changes in OS markers are correlated with levels of labile plasmatic iron and ferritin and the number of transfusions. PMID:25254188

  14. Iron and carbon monoxide attenuate degradation of plasmatic coagulation by Crotalus atrox venom.

    PubMed

    Nielsen, Vance G; Boyer, Leslie V

    2016-07-01

    Hypofibrinogenemia is an important clinical consequence following envenomation by Crotalus species, usually attenuated or prevented by administration of antivenom. It has been determined that iron and carbon monoxide (CO) enhance fibrinogen as a thrombin substrate, likely secondary to conformational changes in molecular structure. We tested the hypothesis that pretreatment of plasma with iron and CO could attenuate the effects of exposure to Crotalus atrox venom. Human plasma was exposed to 0 to 10 μmol/l ferric chloride (iron source) and 0 to 100 μmol/l CO-releasing molecule-2 (CO source) followed by exposure to 0 to 0.5 μg/ml venom for 5 to 20 min. Changes in coagulation kinetics were determined with thrombelastography. Iron and CO significantly attenuated venom-mediated degradation of plasmatic coagulation in terms of onset time, velocity of clot growth and final clot strength. Further preclinical investigation of iron and CO administration as a 'bridge-to-antivenom' to preserve plasmatic coagulation is justified.

  15. Plasmatic hypercoagulation in patients with breast cancer: role of heme oxygenase-1.

    PubMed

    Nielsen, Vance G; Ley, Michele L B; Waer, Amy L; Alger, Patrick W; Matika, Ryan W; Steinbrenner, Evangelina B

    2013-12-01

    Breast cancer is an important health threat to women worldwide, and is associated with a 9-14% incidence of thrombophilia. Of interest, patients with breast cancer have been noted to have an increase in endogenous carbon monoxide production via upregulation of heme oxygenase-1 activity. Given that it has been demonstrated that carbon monoxide enhances plasmatic coagulation in vitro and in vivo, we sought to determine whether patients with breast cancer had an increase in endogenous carbon monoxide and concurrent plasmatic hypercoagulability. Breast cancer patients who were not smokers scheduled to undergo partial or complete mastectomy (n = 18) had 15 ml of whole blood collected via an indwelling intravenous catheter and anticoagulated with sodium citrate. Whole blood was centrifuged and citrated plasma assessed with a thromboelastometric method to measure coagulation kinetics and the formation of carboxyhemefibrinogen. Breast cancer patients were determined to have an abnormally increased carboxyhemoglobin concentration of 2.5 ± 1.3%, indicative of heme oxygenase-1 upregulation. Breast cancer patient plasma on average clotted 73% more quickly and had 32% stronger thrombus strength than normal individual (n = 30) plasma. Further, 44% of breast cancer patients had plasma clot strength that exceeded the 95% confidence interval value observed in normal individuals, and 75% of this hypercoagulable subgroup had carboxyhemefibrinogen formation. Future investigation of the role played by heme oxygenase-1-derived carbon monoxide in the pathogenesis of breast cancer-related thrombophilia is warranted.

  16. Hemodialysis patients have plasmatic hypercoagulability and decreased fibrinolytic vulnerability: role of carbon monoxide.

    PubMed

    Matika, Ryan W; Nielsen, Vance G; Steinbrenner, Evangelina B; Sussman, Amy N; Madhrira, Machaiah

    2014-01-01

    Chronic hemodialysis is associated with significant thrombophilia. Of interest, hemodialysis patients have increased carboxyhemoglobin (COHb) and exhaled carbon monoxide (CO), signs of upregulated heme oxygenase (Hmox) activity. Given that CO enhances plasmatic coagulation, we determined whether patients requiring chronic hemodialysis had an increase in endogenous CO, plasmatic hypercoagulability and decreased fibrinolytic vulnerability. Carbon monoxide was determined by noninvasive pulse oximetry measurement of COHb. Blood samples were obtained just before hemodialysis. Thrombelastographic methods to assess plasma coagulation kinetics, fibrinolytic kinetics, and formation of carboxyhemefibrinogen (COHF) were used. Hemodialysis patients (n = 45) had abnormally increased COHb concentrations of 2.2 ± 1.9%, indicative of Hmox upregulation. Coagulation and fibrinolytic parameter normal values were determined with normal individual (n = 30) plasma. Thirty-seven patients of the hemodialysis cohort had COHF formation (82.2%, [67.9%-92.0%]; mean, [95% confidence interval]), and many of this group of patients had abnormally great velocity of clot growth (73.3%, [58.1%-85.4%]) and strength (75.6%, [60.5%-87.1%]). Furthermore, over half of COHF positive patients had a hypofibrinolytic state, evidenced by an abnormally prolonged time to maximum rate of lysis (53.3%, [37.9%-68.6%]) and clot lysis time (64.4%, [48.8%-78.1%]). Carbon monoxide enhanced coagulation and diminished fibrinolytic vulnerability in hemodialysis patients. Future investigation of hemodialysis, CO-related thrombophilia is warranted.

  17. Bariatric patients have plasmatic hypercoagulability and systemic upregulation of heme oxygenase activity.

    PubMed

    Nielsen, Vance G; Galvani, Carlos A; Boyle, Patrick K; Steinbrenner, Evangelina B; Matika, Ryan W

    2015-03-01

    Morbid obesity is associated with significant thrombophilia. Of interest, adipocytes obtained from obese patients have increased heme oxygenase (Hmox) activity, the endogenous enzyme responsible for carbon monoxide (CO) production. Given that CO enhances plasmatic coagulation, we determined whether morbidly obese patients undergoing bariatric surgery had an increase in endogenous CO and plasmatic hypercoagulability. CO was determined by noninvasive pulse oximetry measurement of carboxyhemoglobin (COHb). A thrombelastographic method to assess plasma coagulation kinetics and formation of carboxyhemefibrinogen (COHF) was utilized. Nonsmoking bariatric patients (n = 20, BMI 47 ± 8 kg/m, mean ± SD) had abnormally increased COHb concentrations of 2.7 ± 1.9%, indicative of Hmox upregulation. When coagulation kinetics of these bariatric patients were compared with values obtained from normal individuals' (n = 30) plasma, 70% (95% confidence interval 45.7-88.1%) had abnormally great velocity of clot formation, abnormally large clot strength, and COHF formation. Future investigation of Hmox-derived CO in the pathogenesis of obesity-related thrombophilia is warranted.

  18. Erythrocyte membrane fluidity and indices of plasmatic oxidative damage after acute physical exercise in humans.

    PubMed

    Berzosa, C; Gómez-Trullén, E M; Piedrafita, E; Cebrián, I; Martínez-Ballarín, E; Miana-Mena, F J; Fuentes-Broto, L; García, J J

    2011-06-01

    Optimal levels of membrane fluidity are essential for numerous cell functions including cell growth, solute transport and signal transduction. Since exercise enhances free radical production, our aim was to evaluate in healthy male subjects the effects of an acute bout of maximal and submaximal exercise on the erythrocyte membrane fluidity and its possible relation to the oxidative damage overproduction due to exercise. Subjects (n = 34) performed three cycloergometric tests: a continuous progressive exercise, a strenuous exercise until exhaustion and an acute bout of exercise at an intensity corresponding to 70% of maximal work capacity for 30 min. Venous blood samples were collected before and immediately after these exercises. Erythrocyte membrane fluidity was assessed by fluorescence spectroscopy. Plasma malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA) concentrations and carbonyl content of plasmatic proteins were used as an index of lipid and protein oxidation, respectively. Exercise produced a dramatic drop in the erythrocyte membrane fluidity as compared to resting time, but this was not accompanied by significant changes in the plasmatic MDA and 4-HDA concentrations. The highest erythrocyte membrane rigidity was detected immediately after strenuous exercise until exhaustion was performed. Protein carbonyl levels were higher after exhaustive exercises than at rest. Continuous progressive and strenuous exercises until exhaustion, but not submaximal workload, resulted in a significant enhanced accumulation of carbonylated proteins in the plasma. These findings are consistent with the idea that exercise exaggerates oxidative damage, which may contribute, at least partially, to explain the rigidity in the membrane of the erythrocytes due to acute exercise.

  19. Diagnostic Potential of Plasmatic MicroRNA Signatures in Stable and Unstable Angina

    PubMed Central

    D'Alessandra, Yuri; Carena, Maria Cristina; Spazzafumo, Liana; Martinelli, Federico; Bassetti, Beatrice; Devanna, Paolo; Rubino, Mara; Marenzi, Giancarlo; Colombo, Gualtiero I.; Achilli, Felice; Maggiolini, Stefano; Capogrossi, Maurizio C.; Pompilio, Giulio

    2013-01-01

    Purpose We examined circulating miRNA expression profiles in plasma of patients with coronary artery disease (CAD) vs. matched controls, with the aim of identifying novel discriminating biomarkers of Stable (SA) and Unstable (UA) angina. Methods An exploratory analysis of plasmatic expression profile of 367 miRNAs was conducted in a group of SA and UA patients and control donors, using TaqMan microRNA Arrays. Screening confirmation and expression analysis were performed by qRT-PCR: all miRNAs found dysregulated were examined in the plasma of troponin-negative UA (n=19) and SA (n=34) patients and control subjects (n=20), matched for sex, age, and cardiovascular risk factors. In addition, the expression of 14 known CAD-associated miRNAs was also investigated. Results Out of 178 miRNAs consistently detected in plasma samples, 3 showed positive modulation by CAD when compared to controls: miR-337-5p, miR-433, and miR-485-3p. Further, miR-1, -122, -126, -133a, -133b, and miR-199a were positively modulated in both UA and SA patients, while miR-337-5p and miR-145 showed a positive modulation only in SA or UA patients, respectively. ROC curve analyses showed a good diagnostic potential (AUC ≥ 0.85) for miR-1, -126, and -483-5p in SA and for miR-1, -126, and -133a in UA patients vs. controls, respectively. No discriminating AUC values were observed comparing SA vs. UA patients. Hierarchical cluster analysis showed that the combination of miR-1, -133a, and -126 in UA and of miR-1, -126, and -485-3p in SA correctly classified patients vs. controls with an efficiency ≥ 87%. No combination of miRNAs was able to reliably discriminate patients with UA from patients with SA. Conclusions This work showed that specific plasmatic miRNA signatures have the potential to accurately discriminate patients with angiographically documented CAD from matched controls. We failed to identify a plasmatic miRNA expression pattern capable to differentiate SA from UA patients. PMID:24260372

  20. The Papillomavirus E2 proteins

    SciTech Connect

    McBride, Alison A.

    2013-10-15

    The papillomavirus E2 proteins are pivotal to the viral life cycle and have well characterized functions in transcriptional regulation, initiation of DNA replication and partitioning the viral genome. The E2 proteins also function in vegetative DNA replication, post-transcriptional processes and possibly packaging. This review describes structural and functional aspects of the E2 proteins and their binding sites on the viral genome. It is intended to be a reference guide to this viral protein. - Highlights: • Overview of E2 protein functions. • Structural domains of the papillomavirus E2 proteins. • Analysis of E2 binding sites in different genera of papillomaviruses. • Compilation of E2 associated proteins. • Comparison of key mutations in distinct E2 functions.

  1. Prediction of atorvastatin plasmatic concentrations in healthy volunteers using integrated pharmacogenetics sequencing.

    PubMed

    Cruz-Correa, Omar Fernando; León-Cachón, Rafael Baltazar Reyes; Barrera-Saldaña, Hugo Alberto; Soberón, Xavier

    2017-01-01

    To use variants found by next-generation sequencing to predict atorvastatin plasmatic concentration profiles (AUC) in healthy volunteers. A total of 60 healthy Mexican volunteers were enrolled in this study. We used variants with a predicted functional effect across 20 genes involved in atorvastatin metabolism to construct a regression model using a support vector approach with a radial basis function kernel to predict AUC refining it afterwards in order to explain a greater extent of the variance. The final support vector regression model using 60 variants (including six novel variants) explained 94.52% of the variance in atorvastatin AUC. An integrated analysis of several genes known to intervene in the different steps of metabolism is required to predict atorvastatin's AUC.

  2. Interaction of warm acclimation, low salinity, and trophic fluoride on plasmatic constituents of the Antarctic fish Notothenia rossii Richardson, 1844.

    PubMed

    Rodrigues, E; Feijó-Oliveira, M; Vani, G S; Suda, C N K; Carvalho, C S; Donatti, L; Lavrado, H P; Rodrigues, E

    2013-12-01

    The adaptive evolution of the Notothenia rossii occurred under the selective pressure of stable and low temperatures. It is an opportunistic feeder of Antarctic krill and the fluoride in the krill carapace is apparently not toxic. We investigated the interactive effect of fluoride, elevated temperatures, and low salinity on the plasmatic constituents of this Antarctic fish. The experiments were conducted at the Brazilian Antarctic Station Comandante Ferraz (EACF), located on King George Island. The Antarctic fish N. rossii was acclimatized to eight thermo-saline-trophic conditions, combining two temperatures (0 and 4 °C), two salinities (35 and 20), and two trophic conditions (with/without fluoride) for an 11-day period. Trophic fluoride was not able to alter the plasmatic levels of glucose, cholesterol, plasmatic protein, Cl⁻, Mg²⁺, Ca²⁺, and inorganic phosphate, but induced an acute elevation of triglycerides at 0 °C and salinity of 35. At low salinity, hyperglycemia, hypertriglyceridemia, and hypocalcemia were observed. The thermo-saline interaction at 4 °C was able to minimize the effects of fluoride and low salinity on the plasmatic constituents levels.

  3. Variants and Haplotypes in Angiotensinogen Gene Are Associated With Plasmatic Angiotensinogen Level in Mexican Population

    PubMed Central

    Balam-Ortiz, Eros; Esquivel-Villarreal, Adolfo; Alfaro-Ruiz, Luis; Carrillo, Karol; Elizalde, Adela; Gil, Trinidad; Urushihara, Maki; Kobori, Hiroyuki; Jimenez-Sanchez, Gerardo

    2011-01-01

    Introduction The plasmatic angiotensinogen (AGT) level has been associated with essential hypertension. Linkage analysis has found a relationship between the AGT gene locus and hypertension in the Mexican-American population, but studies have failed to identify genetic variants associated with hypertension or plasma AGT levels. This study analyzes the relationship between polymorphisms in the AGT gene and plasmatic AGT levels in Mexican population. Methods Nine polymorphisms in AGT gene were genotyped, and plasma AGT level was determined by enzyme-linked immunosorbent assay. Results Differences in AGT plasma levels were associated with 2 polymorphisms: T-20G, TT = 25.3 ± 8.3 versus TG + GG = 21.6 ± 8.8 μg/mL; P = 0.008 and C3389T (T174M), CC = 25.8 ± 9.9 versus TC + TT = 20.5 ± 5.4 μg/mL; P = 0.0002. Haplotype 2 was associated with low plasma AGT (−5.1 μg/mL [95% confidence interval: −8.6 to −1.6], P = 0.004) and Haplotype 8 was associated with high plasma AGT (6.5 μg/mL [95% confidence interval: 2.5 to 10.6], P = 0.001). This association remained after adjustment for covariates. A Likelihood Ratio Test for haplotype-phenotype association adjusted for covariates resulted in χ2 = 38.9, P = 0.0005. The total effect of the haplotypes on plasma AGT level variance was 19.5%. No association was identified between haplotypes and quantitative traits of blood pressure. Conclusions Two polymorphisms (T-20G and C3389T) and 2 haplotypes (H2 and H8) showed an association with plasma AGT levels in Mexican population. PMID:21629041

  4. The Papillomavirus E2 Proteins

    PubMed Central

    McBride, Alison A.

    2013-01-01

    The papillomavirus E2 proteins are pivotal to the viral life cycle and have well characterized functions in transcriptional regulation, initiation of DNA replication and partitioning the viral genome. The E2 proteins also function in vegetative DNA replication, post-transcriptional processes and possibly packaging. This review describes structural and functional aspects of the E2 proteins and their binding sites on the viral genome. It is intended to be a reference guide to this viral protein. PMID:23849793

  5. Pathogenic infection confounds induction of the estrogenic biomarker vitellogenin in rainbow trout

    USDA-ARS?s Scientific Manuscript database

    To examine the behavior of the estrogenic biomarker vitellogenin (VTG) under the combined impact of estrogens and pathogens, parasite-infected or noninfected rainbow trout were exposed to two doses of 17 beta-estradiol (E2). Infected and E2-exposed fish showed significantly lower hepatic VTG mRNA le...

  6. Plasmatic coagulation and fibrinolysis in healthy and Otostrongylus-affected Northern elephant seals (Mirounga angustirostris).

    PubMed

    Kaye, Sarrah; Johnson, Shawn; Rios, Carlos; Fletcher, Daniel J

    2017-09-13

    Prepatent Otostrongylus arteritis results in hemorrhagic diathesis in free-ranging Northern elephant seals (Mirounga angustirostris) attributed to aberrant larval migration of the lungworm, Otostrongylus circumlitus. Clinical signs are often nonspecific, including lethargy, anorexia, and blepharospasm, but can progress to spontaneous frank hemorrhage and death within 72 hours of onset. Previously published case reports describe coagulopathy with prolonged PT and APTT, normal to elevated platelet counts, normal antithrombin concentrations, and low concentrations of fibrinogen degradation products. Disseminated intravascular coagulation was proposed as the cause of hemorrhage, but is inconsistent with some of the reported clinicopathologic changes. The purpose of this study was to compare plasmatic coagulation and fibrinolysis in healthy and Otostrongylus-affected elephant seals, in order to identify potential therapy. We hypothesized that hyperfibrinolysis contributed to hemorrhage in these cases. Citrated plasma samples were collected from 3- to 4-month-old Northern elephant seals in a wildlife rehabilitation hospital. The sampled population included 25 healthy, prerelease seals and 32 clinically ill seals diagnosed with presumptive Otostrongylus arteritis. Twenty-one of the included seals had Otostrongylus infestation confirmed at necropsy. Standard coagulation tests and plasma thromboelastography were performed for a complete assessment of coagulation and fibrinolysis. Northern elephant seals with definitive Otostrongylus infestation were hypocoagulable and hypofibrinolytic compared to healthy controls. Results were most consistent with disseminated intravascular coagulation. Treatment with antifibrinolytic drugs to control hemorrhage may be unrewarding; alternative therapies such as plasma transfusions or coagulation factor concentrates should be investigated. © 2017 American Society for Veterinary Clinical Pathology.

  7. Plasmatic proinflammatory chemokines levels are tricky markers to monitoring HTLV-1 carriers.

    PubMed

    Chaves, Daniel Gonçalves; Sales, Camila Campos; de Cássia Gonçalves, Poliane; da Silva-Malta, Maria Clara Fernandes; Romanelli, Luiz Cláudio; Ribas, João Gabriel; de Freitas Carneiro-Proietti, Anna Bárbara; Martins, Marina Lobato

    2016-08-01

    The human T-cell leukemia virus type 1 (HTLV-1) is present throughout the world and is associated with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and other inflammatory conditions. The pathogenesis of HAM/TSP involves a chronic inflammatory response in central nervous system (CNS), with the presence of HTLV-1 infected cells and HTLV-1-specific CD8+ lymphocytes. Chemokines may have a role in the infiltration of these cells into the CNS. In this context, the present study analyzed the level of plasmatic chemokines CCL2 (MCP-1), CCL5 (RANTES), IL8 (CXCL8), CXCL9 (MIG), and CXCL10 (IP-10) and HTLV-1 proviral load from peripheral blood in 162 asymptomatic carriers and 136 HAM/TSP patients to determine the differences that be associated with the clinical status of the HTLV-1 infection. The results showed that patients with HAM/TSP have significantly higher levels of IL8 and CXCL9, and that the level of IL8, CXCL9 and CXCL10 was significantly greater in HTLV-1 infected individuals with high (>1%) than those with low proviral load (<1%). However, the levels of the chemokines tested have not showed high sensitivity to discriminate HAM/TSP patients from asymptomatic carriers. In addition, chemokine profiles in asymptomatic carriers and HAM/TSP groups were similar, with no significant increased frequency of higher producers of chemokines in HAM/TSP individuals. Results indicate that the heterogeneity of the individuals in the groups regarding time of infection, duration of disease, proviral load level and other possible confound factors may impair the use of chemokines levels to monitor HTLV-1 carriers in clinical practice. J. Med. Virol. 88:1438-1447, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. [Plasmatic pattern and clinical outcomes of lactic acid in heart transplantation].

    PubMed

    Arias, Aníbal M; Leyendecker, Vanina; Pizarro, Rodolfo; Lucas, Luciano; Vulcano, Norberto; Marenchino, Ricardo G; Del Castillo, Santiago; Cagide, Arturo M; Belziti, Cesar A

    It is not well established the prognostic value of elevated lactic acid after heart transplantation. To evaluate the plasmatic pattern and the prognostic value of elevated lactate after heart transplantation. One-hundred and twenty seven patients were included between 2011 and 2014, 71 comprising the transplantation group and 56 the control group, represented by on pump coronary artery by-pass surgery patients. Lactic acid levels were compared between groups before, within and after surgery upon Coronary Care Unit admission, at 6, 12 and 24h. In addition, in the transplantation group univariate and bivariate analysis were performed between lactic acid levels and in-hospital mortality. The mean age of the entire cohort was 57 years. Among transplanted patients, lactic acid levels were significantly higher over control group: within the surgery; and after surgery (P<.001), but not before surgery (P=.143; unadjusted comparisons). In transplanted patients, lactic acid levels were significantly associated with in-hospital mortality during surgery, at admission, and thereafter but not before surgery. Lactic acid at admission was associated with in-hospital mortality after adjustment of postoperative cardiac output (P=.011),≥2 inotropic drug support within 24h (P=.033), glycemic level at admission (P=.004), age≥60 years (P=.015), on pump time (P=.027), and pH (P=.017). Acid lactic levels were higher in transplanted patients than in the control group and was associated to higher in-hospital mortality. Copyright © 2016 Instituto Nacional de Cardiología Ignacio Chávez. Publicado por Masson Doyma México S.A. All rights reserved.

  9. Plasmatic isoforms of cytokeratin 18 and RAGE after severe trauma: a longitudinal cohort study.

    PubMed

    Uhle, Florian; Nouland, Denise van den; Little, Simon; Menges, Thilo; Weiterer, Sebastian; Szalay, Gabor; Franke, Jörg; Schnettler, Reinhard; Weigand, Markus Alexander; Lichtenstern, Christoph

    2014-10-01

    Life-threatening traumatic injuries lead to a complex inflammation-driven pathophysiology. Receptor of advanced glycation end product (RAGE) is a multiligand receptor of several endogenous alarmins, while cytokeratin 18 is a structural component of the filament of epithelial cells. Both proteins can be frequently found in plasma of patients with different diseases, whereby they have distinct underlying mechanism of formation. In this prospective observational study, we wanted to shed light on the kinetic of plasmatic RAGE and cytokeratin 18 isoforms after severe trauma, thereby also addressing the association of these markers with inflammation and their potential use as biomarkers. Plasma samples of 77 patients with severe multiple trauma as defined by an Injury Severity Score (ISS) 16 or greater were obtained from a local repository and levels of soluble RAGE, endogenous secretory RAGE, cytokeratin 18, cleaved cytokeratin 18, and interleukin 6 by enzyme-linked immunosorbent assay. Demographic and routine parameters of the cohort were extracted from an electronic patient data management system. Both RAGE isoforms were transiently increased in plasma within 24 hours after trauma, while cytokeratin 18 levels were unchanged. Moreover, soluble RAGE concentrations in patients with thoracic injuries were higher compared with patients without injury, and both isoforms of RAGE discriminated between patients with most severe adult respiratory distress syndrome and patients with milder forms. In addition, cleaved and total cytokeratin 18 levels differ between patients with hepatic dysfunction and normal function, without possessing discriminatory power. RAGE and cytokeratin 18 isoforms correlated significantly but to a low extent with interleukin 6, while the isoforms of both parameters correlated to a high extent with one another. The release of RAGE (but not cytokeratin 18) isoforms occurs early and transiently after trauma and is associated with the extent of injury and

  10. New combined microRNA and protein plasmatic biomarker panel for pancreatic cancer

    PubMed Central

    Xie, Yibin; Wang, Shaoming; Chen, Yingtai; Qi, Jun; Qiao, Youlin; Ma, Jie

    2016-01-01

    Introduction Lack of diagnostic makers results in loss of operation opportunity in that most patients are diagnosed at the late stage. Pancreatic cancer (PC) has been regarded as a fatal disease with a 5-year survival rate below 10%. Therefore, the development of diagnostic biomarkers for PC is in urgent need to control the mortality of the disease. Materials and Methods This is a case-control study including 640 plasma samples from healthy controls (HC), patients with benign pancreatic diseases (BPD), patients with PC; and patients with other gastrointestinal (GI) cancers. Eight biomarker candidates, including miR-20a, miR-21, miR-25, miR-155, miR-196a, miR-210, Macrophage Inhibitory Cytokine-1(MIC-1) and CA19-9, were evaluated to establish two diagnostic indexes in this study. Results The plasma level of the six miRNAs and MIC-1, CA19-9 were elevated in PC patients compared with those of healthy controls (P<0.001). Among them, miR-20a, miR-21, miR-25, MIC-1 and CA19-9 could distinguish PC patients from those with other GI cancers or BPD. With multivariable logistic regression, we established two specific indexes for diagnosis of PC(Index1 contains miR-21, MIC-1 and CA19-9; Index2 contains miR-25, MIC-1 and CA19-9). In a randomized setting of 260 HC, 168 PC, 132 other GI cancers and 80 BPD patients, both indexes performed not only better sensitivity for PC but also better specificity to distinguish PC from other GI cancers than CA19-9 and individual biomarkers. Conclusions These results indicated that combination of biomarkers as a panel could improve diagnostic values compared with using a single marker. Such panels as illustrated in this study could provide novel plasmatic biomarker for PC diagnosis. PMID:27713117

  11. Degradation and metabolite formation of estrogen conjugates in an agricultural soil

    USDA-ARS?s Scientific Manuscript database

    Estrogen conjugates are precursors of free estrogens such as 17beta-estradiol (E2) and estrone (E1), which causes potent endocrine disrupting effects on aquatic organisms. In this study, microcosm laboratory experiments were conducted in an agricultural soil to investigate the aerobic degradation an...

  12. Differential effects of short term feeding of a soy protein isolate diet and estrogen treatment on bone in the pre-pubertal rat

    USDA-ARS?s Scientific Manuscript database

    Beneficial effects of a soy diet on bone quality have been assumed to be due to the putative estrogenic actions of isoflavones. We studied the effects of soy protein isolate (SPI) on bone quality and compared these effects to 17 beta-estradiol (E2) in pre-pubertal rats. Female rats were weaned to a ...

  13. E-2D Advanced Hawkeye Aircraft (E-2D AHE)

    DTIC Science & Technology

    2015-12-01

    and Homeland Defense. As a part of the E-2D AHE radar modernization effort, the Navy also invested in integrating a full glass cockpit and full...Communication Navigation Surveillance/Air Traffic Management capability. The glass cockpit will also provide the capability for the pilot or co-pilot to...hours at a station distance of 200nm Flat Turn Service Ceiling =>25,000 feet above MSL at mission profile =>25,000 feet above MSL at mission

  14. Influence of arsenic and cyanobacteria co-exposure on plasmatic parameters of rainbow trout (Oncorhynchus mykiss W.).

    PubMed

    Kopp, Radovan; Mares, Jan; Soukupova, Zdenka; Navratil, Stanislav; Palikova, Miroslava

    2014-01-01

    Fish can be exposed under environmental conditions to multiple stressors including natural toxins and environmental or feed contamination at the same time. This study brings new knowledge about the effects of controlled exposure to multiple stressors in fish. The aim of this study was to test the hypothesis that influence of cyanobacterial biomass and arsenic in feed can combine to enhance the effects on fish. Rainbow trouts were sorted into six groups, each with 25 specimens: control group (fed with commercial feed), groups exposed to toxic cyanobacterial biomass (81 mg x kg(-1) MCs of feed), two groups exposed to arsenic (concentration of 5 mg x kg(-1), and 50 mg x kg(-1) of fish feed) and two groups exposed to combination of cyanobacterial biomass and arsenic in two concentrations mentioned above. The experiment lasted 30 days. During the experiment we evaluated the influence of co-exposure on plasmatic parameters mentioned above. Samples were collected on days 10, 20 and 30 of exposure. Biochemical analysis revealed a significant decrease in calcium (T20) and an increase in natrium (T10) and chlorides (T10) values in combined cyanobacterial and arsenic exposures. Our results showed a significant decrease in the values of magnesium after exposure to higher concentration of arsenic compared to control and feeding with addition of cyanobacterial biomass groups. The changes of other monitored plasmatic parameters were not significantly increased or decreased in comparison with controls. Our results confirmed the hypothesis that influence of toxic cyanobacterial biomass and a chemical agent represented by arsenic can combine to enhance the effects on fish. This work originally shows that while the single agents in sub-lethal doses do not cause changes in the plasmatic parameters, their co-exposure leads to the significantly decrease or increase of the electrolytes of rainbow trout.

  15. Advanced Glycation End Products Evolution after Pancreas-Kidney Transplantation: Plasmatic and Cutaneous Assessments

    PubMed Central

    Oliveira, José C.; Vizcaíno, José Ramón; Gouveia, Carlos; Silva, Donzília; Henriques, António C.; Noronha, Irene L.; Rodrigues, Anabela

    2016-01-01

    Diabetes mellitus leads to increased Advanced Glycation End Products (AGE) production, which has been associated with secondary diabetic complications. Type 1 diabetic patients undergoing pancreas-kidney transplantation (SPKT) can restore normoglycemia and renal function, eventually decreasing AGE accumulation. We aimed to prospectively study AGE evolution after SPKT. Circulating AGE were assessed in 20 patients, at time 0 (T0), 3 months (T3), 6 months (T6), and 12 months (T12) after successful SPKT. Global AGE and carboxymethyllysine (CML) were analyzed, as well as advanced oxidation protein products (AOPP). Skin biopsies were obtained at T0 and T12. Immunohistochemistry with anti-AGE antibody evaluated skin AGE deposition. AGE mean values were 16.8 ± 6.4 μg/mL at T0; 17.1 ± 3.8 μg/mL at T3; 17.5 ± 5.6 μg/mL at T6; and 16.0 ± 5.2 μg/mL at T12. CML mean values were 0.94 ± 0.36 ng/mL at T0; 1.11 ± 0.48 ng/mL at T3; 0.99 ± 0.42 ng/mL at T6; and 0.78 ± 0.38 ng/mL at T12. AOPP mean values were 130.1 ± 76.8 μMol/L at T0; 137.3 ± 110.6 μMol/L at T3; 116.4 ± 51.2 μMol/L at T6; and 106.4 ± 57.9 μMol/L at T12. CML variation was significant (P = 0.022); AOPP variation was nearly significant (P = 0.076). Skin biopsies evolved mostly from a cytoplasmic diffuse to a peripheral interkeratinocytic immunoreaction pattern; in 7 cases, a reduction in AGE immunoreaction intensity was evident at T12. In conclusion, glycoxidation markers decrease, plasmatic and on tissues, may start early after SPKT. Studies with prolonged follow-up may confirm these data. PMID:26881017

  16. Effects of 17beta-estradiol and progesterone on transcription of human papillomavirus 16 E6/E7 oncogenes in CaSki and SiHa cell lines.

    PubMed

    Ruutu, M; Wahlroos, N; Syrjänen, K; Johansson, B; Syrjänen, S

    2006-01-01

    Several in vitro studies have addressed the interactions between estrogen/progesterone and human papillomavirus (HPV), but the results are controversial. We evaluated the effects of estrogen and progesterone and their antagonists on messenger RNA expression of HPV16 E6/E7 in HPV16-positive cell lines CaSki and SiHa with real-time reverse-transciptase polymerase chain reaction method. Colorimetric assay with tetrazolium salt (WST-1) and flow cytometry were used for testing proliferation and apoptosis. No statistically significant changes were found after hormone treatment in the expression of HPV16 E6/E7 or hormone receptors in CaSki and SiHa cell lines. Progesterone increased cell proliferation in both the cells, while estrogen increased proliferation of SiHa cells only. Estrogen seemed to protect the CaSki cells from apoptosis, and tamoxifen did not abrogate this effect. Progesterone slightly increased apoptosis of CaSki cells, and this effect was neutralized with RU486. In this study, estrogen and progesterone did not change either the transcription levels of HPV16 E6/E7 or estrogen receptor or progesterone receptor levels. Hormone receptor antagonists had no effect on transcription. Both hormones might have a permissive effect for the growth of cervical cancer, by promoting cell proliferation and making the cells vulnerable to mutations. In addition, estrogen acts as an antiapoptotic agent allowing growth advance of the cells infected with oncogenic HPV.

  17. Comparison of the pharmacokinetics of 17 beta-estradiol after a single 4-day application of Oesclim 50, Oesclim 100, and Vivelle 0.05 (Menorest 50) transdermal delivery systems.

    PubMed

    Guichard, J P; Sauron, R; Jones, A B

    1999-08-01

    Oesclim (Laboratoires Fournier, Dijon, France), also known as Esclim or Esclima, is a new estradiol transdermal delivery system (TDS) developed for the treatment of menopausal vasomotor symptoms. This open, randomized, three-way crossover study compared in 24 healthy postmenopausal women the pharmacokinetics of estradiol after a single 4-day application of Oesclim 50, Oesclim 100, and Vivelle 0.05 (CibaGeneva Pharmaceuticals, Summit, NJ; known as Menorest 50 in Europe, Rhône-Poulenc Rorer) on the upper buttock. Serum estradiol concentrations were determined by a validated radioimmunoassay method from samples taken before and during each TDS application. The concentration-time profiles for Vivelle 0.05 and Oesclim 50 were comparable with a similar absorption rate, giving a maximum concentration (Cmax) of 49 and 53 pg/mL above baseline, respectively, followed by a plateau throughout the 96-hour application period. At the end of this period, mean corrected estradiol concentrations were 18 and 19 pg/mL, respectively. The estradiol serum concentrations obtained after an application of Oesclim 100 were approximately twice as high than with Oesclim 50. All products were well tolerated, but skin intolerance was more frequent with Vivelle 0.05 (4 patients; four reports) and Oesclim 100 (3 patients; three reports) than with Oesclim 50 (none). Problems of imperfect adhesion were more than five times as frequent with Vivelle 0.05 (44%) than with Oesclim (8%).

  18. E2f2 induces cone photoreceptor apoptosis independent of E2f1 and E2f3

    PubMed Central

    Chen, D; Chen, Y; Forrest, D; Bremner, R

    2013-01-01

    The ‘activating' E2fs (E2f1-3) are transcription factors that potently induce quiescent cells to divide. Work on cultured fibroblasts suggested they were essential for division, but in vivo analysis in the developing retina and other tissues disproved this notion. The retina, therefore, is an ideal location to assess other in vivo adenovirus E2 promoter binding factor (E2f) functions. It is thought that E2f1 directly induces apoptosis, whereas other activating E2fs only induce death indirectly by upregulating E2f1 expression. Indeed, mouse retinoblastoma (Rb)-null retinal neuron death requires E2f1, but not E2f2 or E2f3. However, we report an entirely distinct mechanism in dying cone photoreceptors. These neurons survive Rb loss, but undergo apoptosis in the cancer-prone retina lacking both Rb and its relative p107. We show that while E2f1 killed Rb/p107 null rod, bipolar and ganglion neurons, E2f2 was required and sufficient for cone death, independent of E2f1 and E2f3. Moreover, whereas E2f1-dependent apoptosis was p53 and p73-independent, E2f2 caused p53-dependent cone death. Our in vivo analysis of cone photoreceptors provides unequivocal proof that E2f-induces apoptosis independent of E2f1, and reveals distinct E2f1- and E2f2-activated death pathways in response to a single tumorigenic insult. PMID:23558950

  19. LPS-induced c-Fos activation in NTS neurons and plasmatic cortisol increases in septic rats are suppressed by bilateral carotid chemodenervation.

    PubMed

    Reyes, Edison-Pablo; Abarzúa, Sebastián; Martin, Aldo; Rodríguez, Jorge; Cortés, Paula P; Fernández, Ricardo

    2012-01-01

    Lipopolysaccharide (LPS) administered I.P. increases significantly the activation of c-Fos in neurons of the nucleus of the solitary tract (NTS), which in turn activates hypothalamus-pituitary-adrenal axis. The vagus nerve appears to play a role in conveying cytokines signals to the central nervous system (CNS), since -in rodent models of sepsis- bilateral vagotomy abolishes increases in plasmatic glucocorticoid levels, but does not suppress c-Fos NTS activation. Considering that NTS also receives sensory inputs from carotid body chemoreceptors, we evaluated c-Fos activation and plasmatic cortisol levels 90 min after I.P. administration of 15 mg/kg LPS. Experiments were performed in male Sprague-Dawley rats, in control conditions and after bilateral carotid neurotomy (BCN). LPS administration significantly increases the number of c-Fos positive NTS neurons and plasmatic cortisol levels in animals with intact carotid/sinus nerves. When LPS was injected after BCN, the number of c-Fos positive NTS neurons, and plasmatic cortisol levels were not significantly modified. Our data suggest that carotid body chemoreceptors might mediate CNS activation during sepsis.

  20. ApoC-I and ApoC-III as potential plasmatic markers to distinguish between ischemic and hemorrhagic stroke.

    PubMed

    Allard, Laure; Lescuyer, Pierre; Burgess, Jennifer; Leung, Kit-Yi; Ward, Malcolm; Walter, Nadia; Burkhard, Pierre R; Corthals, Garry; Hochstrasser, Denis F; Sanchez, Jean-Charles

    2004-08-01

    Early diagnosis and immediate therapeutic interventions are crucial factors to reduce the damage extent and the risk of death. Currently, the diagnosis of stroke relies on neurological assessment of the patient and neuro-imaging techniques including computed tomography and/or magnetic resonance imaging scan. An early diagnostic marker of stroke, ideally capable to discriminate ischemic from hemorrhagic stroke would considerably improve patient acute management. Using surface-enhanced laser desorption/ionization (SELDI) technology, we aimed at finding new early diagnostic plasmatic markers of stroke. Strong anionic exchange (SAX) SELDI profiles of plasma samples from 21 stroke patients were compared to 21 samples from healthy controls. Seven peaks appeared to be differentially expressed with significant p values (p < 0.05). Proteins were stripped from the SAX chips, separated on a one-dimensional electrophoresis (1-DE) gel and stained using mass spectrometry (MS)-compatible silver staining. Following in-gel tryptic digestion, the peptides were analyzed by MS. Four candidate proteins were identified as apolipoprotein CI (ApoC-I), apolipoprotein CIII (ApoC-III), serum amyloid A (SAA), and antithrombin-III fragment (AT-III fragment). Assessment of ApoC-I and ApoC-III levels in plasma samples using a sandwich enzyme-linked immunosorbent assay (ELISA) allowed to distinguish between hemorrhagic (n = 15) and ischemic (n = 16) stroke (p < 0.001). To the best of our knowledge, ApoC-I and ApoC-III are the first reported plasmatic biomarkers capable to accurately distinguish between ischemic and hemorrhagic stroke in a small number of patients. It requires further investigation in a large cohort of patients.

  1. Content of plasmatic glycerol and activity of hepatic glycerol kinase in broiler chickens fed diets containing different sources and concentrations of glycerine.

    PubMed

    Bernardino, V M P; Rodrigues, P B; de Paula Naves, L; Rosa, P V; Zangerônimo, M G; Gomide, E M; Saldanha, M M; Alvarenga, R R

    2014-04-01

    The objective of this study was to evaluate the effect of three sources of glycerine (crude glycerine from soya bean oil - CGSO, mixed crude glycerine from frying oil and lard--MCG, and a semipurified glycerine from soya bean oil--SPGSO) in four concentrations in the diet (17.5, 35.0, 52.5 and 70.0 g of each type of glycerine per kg of feed) on the levels of plasmatic glycerol and the activity of the hepatic enzyme glycerol kinase in broilers of 22-35 days old (experiment I) and 33-42 days old (experiment II). The highest (p < 0.05) plasmatic glycerol level was detected in broilers fed diet containing CGSO. Independent of the source, increasing the concentration of glycerine led to a linear increase (p < 0.05) in the plasmatic glycerol concentration. In experiment I, all the diets containing glycerine resulted in increased concentrations of plasmatic glycerol, in relation to the control diet without glycerine. However, in experiment II, only the diet containing 17.5 g of CGSO per kg of feed and the diets formulated with any of the three types of glycerine in the inclusion concentrations of 35, 52.5 and 70 g/kg of feed resulted in higher plasmatic glycerol levels than those observed in the control broilers. The source of glycerine influenced the glycerol kinase activity only in experiment II, where the use of CGSO in the diet increased the enzyme activity. For both experiments, the glycerol kinase activity increased with the inclusion of glycerine in the diet. In conclusion, based on the absence of saturation of the glycerol kinase activity for the three glycerine sources and for both rearing periods evaluated, the broilers can metabolize the glycerol (at the level of the phosphorylation of the glycerol to glycerol-3-phosphate in the liver) present in the glycerine when the diet is supplemented with up to 70 g of glycerine per kg of feed.

  2. Atypical E2Fs inhibit tumor angiogenesis.

    PubMed

    Weijts, B G M W; Westendorp, B; Hien, B T; Martínez-López, L M; Zijp, M; Thurlings, I; Thomas, R E; Schulte-Merker, S; Bakker, W J; de Bruin, A

    2017-09-18

    Atypical E2F transcription factors (E2F7 and E2F8) function as key regulators of cell cycle progression and their inactivation leads to spontaneous cancer formation in mice. However, the mechanism of the tumor suppressor functions of E2F7/8 remain obscure. In this study we discovered that atypical E2Fs control tumor angiogenesis, one of the hallmarks of cancer. We genetically inactivated atypical E2Fs in epithelial and mesenchymal neoplasm and analyzed blood vessel formation in three different animal models of cancer. Tumor formation was either induced by application of 7,12-Dimethylbenz(a)anthracene/12-O-Tetradecanoylphorbol-13-acetate or by Myc/Ras overexpression. To our surprise, atypical E2Fs suppressed tumor angiogenesis in all three cancer models, which is in a sharp contrast to previous findings showing that atypical E2Fs promote angiogenesis during fetal development in mice and zebrafish. Real-time imaging in zebrafish displayed that fluorescent-labeled blood vessels showed enhanced intratumoral branching in xenografted E2f7/8-deficient neoplasms compared with E2f7/8-proficient neoplasms. DLL4 expression, a key negative inhibitor of vascular branching, was decreased in E2f7/8-deficient neoplastic cells, indicating that E2F7/8 might inhibit intratumoral vessel branching via induction of DLL4.Oncogene advance online publication, 18 September 2017; doi:10.1038/onc.2017.336.

  3. Effects of selected xenobiotics on hepatic and plasmatic biomarkers in juveniles of Solea senegalensis.

    PubMed

    Solé, Montserrat; Fortuny, Anna; Mañanós, Evaristo

    2014-11-01

    In recent years, Solea senegalensis has increasingly been used in pollution monitoring studies. In order to assess its response to some particular widespread pollutants, juveniles of S. senegalensis were administered an intraperitoneal injection of the model aryl hydrocarbon receptor agonist β-naphtoflavone (βNF) and chemicals of environmental concern, such as the fungicide ketoconazole (KETO), the lipid regulator gemfibrozil (GEM), the surfactant nonylphenol (NP) and the synthetic hormone ethinylestradiol (EE2). Two days after injection, the effect of these chemicals was followed up as alterations of hepatic microsomal activities of the cytochrome P450 (CYPs) and associated reductases, carboxylesterases (CbEs) and the conjugation enzyme uridine diphosphate glucuronyltransferase (UDPGT). In the cytosolic fraction of the liver, the effect on CbEs, glutathione S-transferase (GST) and antioxidant activities was also considered. Alterations on the endocrine reproductive system were evaluated by plasma levels of vitellogenin (VTG) and the sex steroids estradiol (E2), testosterone (T), 11-ketotestosterone (11KT) and the progestin 17α,20β-dihydroxy-4-pregnen-3-one (17,20β-P). Injection with the model compound βNF induced the hydrolysis rate of the seven CYP substrates assayed. The xenobiotic GEM induced three CYP-related activities (e.g. ECOD) and UDPGT, but depressed antioxidant defenses. EE2 induced four CYPs, more significantly ECOD and BFCOD activities. The xenoestrogens NP and EE2 altered the activities of CbE in microsomes and catalase, and were the only treatments that induced de novo VTG synthesis. In addition, the progestin 17,20β-P, was induced in NP-injected fish. None of the treatments caused statistically significant effects on steroid plasma levels. In conclusion, the CYP substrates assayed responded specifically to treatments and juveniles of S. senegalensis appear good candidates for assessing xenobiotics exposure.

  4. Effect of iron and carbon monoxide on fibrinogenase-like degradation of plasmatic coagulation by venoms of four Crotalus species.

    PubMed

    Nielsen, Vance G; Redford, Daniel T; Boyle, Patrick K

    2017-01-01

    Annually, thousands suffer poisonous snake bite, often from defibrinogenating species. Iron and carbon monoxide (CO) improve coagulation kinetics by modulation of fibrinogen as demonstrated in various Agkistrodon species and Crotalus atrox. Thus, we sought to determine whether pretreatment of plasma with iron and CO could attenuate venom-mediated catalysis of fibrinogen obtained from four common Crotalus species with known fibrinogenase activity. Human plasma was pretreated with ferric chloride (0-10 μmol/l) and CO-releasing molecule-2 (0-100 μmol/l) prior to exposure to venom from a Northern Pacific rattlesnake, Arizona black rattlesnake, prairie rattlesnake, or red diamond rattlesnake. The concentration of venom used decreased coagulation function of one or more kinetic parameters by at least 50% of normal values. Coagulation kinetics were determined with thrombelastography.Three snake venoms significantly degraded plasmatic coagulation kinetics, prolonging the onset to clot formation, diminishing velocity of clot growth and decreasing clot strength. However, red diamond rattlesnake venom exposure resulted in mixed coagulation kinetics, significantly decreasing the time to onset of coagulation without decreasing the velocity of clot growth. Iron and CO attenuated these coagulation kinetic changes in a species-specific manner. Further in vitro investigation of other fibrinogenolytic venoms is indicated to determine if iron and CO can attenuate venom compromised coagulation.

  5. Drospirenone intake alters plasmatic steroid levels and cyp17a1 expression in gonads of juvenile sea bass.

    PubMed

    Blanco, Maria; Fernandes, Denise; Medina, Paula; Blázquez, Mercedes; Porte, Cinta

    2016-06-01

    Drospirenone (DRO) is one of the most widely used progestins in contraceptive treatments and hormone replacement therapies. The pharmacokinetics and potential toxicological effects of DRO were investigated in juvenile sea bass (Dicentrarchus labrax) exposed through the diet (0.01-10 μg DRO/g) for up to 31 days. DRO was detected in the blood (4-27 ng/mL) of fish exposed to the highest concentration, with no significant bioaccumulation over time and no alteration of hepatic metabolizing enzymes, namely, CYP1A and CYP3A-catalysed activities and UDP-glucuronyltransferase (UGT). Pregnenolone (P5), progesterone (P4), 17α-hydroxyprogesterone (17P4), 17α-hydroxypregnenolone (17P5), androstenedione (AD) and testosterone (T) were determined in plasma and gene expression of cyp17a1, cyp19a1a and cyp11β analysed by qRT-PCR in gonads. The significant increase in plasmatic levels of 17P5, 17P4 and AD detected after 31 days exposure to 10 ng DRO/g together with the increased expression of cyp17a1 in females evidence the ability of DRO to alter steroid synthesis at low intake concentrations (7 ng DRO/day). However, the potential consequences of this steroid shift for female reproduction remain to be investigated.

  6. Effects of the presence of indium on the mammary gland ultrastructure, body weight, food intake and plasmatic prolactin concentration.

    PubMed

    Ayadi, Ahlem; Maghraoui, Samira; Kammoun, Sayda; Tekaya, Leila

    2014-10-01

    Several studies have demonstrated the toxic effect of indium. This element induces impairments in many organs such as spleen, lungs and testicles after its systemic administration. Teratogenic and embryotoxic effects of this element have also been established. In the present study, we attempt to investigate the histological and the ultrastructural consequences of the presence of this element in mammary gland tissue using conventional transmission electron microscopy and to evaluate the incidences of its presence on the food intake, body weight and prolactin plasmatic concentration of lactating female rats. Our study showed that this element induced a significant decrease in food intake and body weight, and caused some cellular damage in the glandular epithelial cell such as cytoplasmic vacuolization and expansion of the ergastoplasm. The ultrastructural observations also showed many electron-dense surcharges in the lysosomes of the glandular epithelial cells. The electron probe microanalysis showed that these deposits are composed of indium and phosphorus. The lysosomes, known for their protective role of sequestrating foreign elements to avoid their diffusion in the blood, failed to stop the toxic effect of indium. © The Author 2014. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. [Pilot study on predictive value of plasmatic levels of 9 angiogenetic biomarkers in selection of patients candidate to prostate biopsy].

    PubMed

    Serretta, Vincenzo; Scurria, Salvatore; Dispensa, Nino; Chiapparrone, Gaetano; Provenzano, Sandro; Caruso, Stefano; Bronte, Giuseppe; Cicero, Giuseppe; Russo, Antonio

    2013-01-01

    To reduce the number of negative prostate biopsies in patients with elevated PSA serum levels represents a major challenge in urological oncology. Angiogenetic factors might be involved in initial stages of prostate cancer and might represent useful tools in patients' selection for prostate biopsy. The plasmatic levels of Angiopoietin-2, Follistatin, G-CSF, HGF, IL-8, Leptin, PDGF-BB, PECAM-1 and VEGF were measured by BioPlex immunoassay in patients undergoing prostate biopsy for palpable prostate nodule and/or elevated PSA levels (≥4 ng/mL). They were related with biopsy results. ROC curve analysis was exploited to test the diagnostic accuracy of each biomarker by AUC calculation. A potential cut-off level was computed. Fifty patients were entered. Median PSA was 6.8 ng/mL. A prostate nodule was palpable in 18 (36%) patients. The median number of biopsy cores was 12. Prostate cancer was detected in 25 (50%) and ASAP and PIN in 2 more patients (4%) respectively. Among the 9 considered biomarkers, only leptin showed an interesting diagnostic performance with an AUC of 0.781, at a cut-off value of 2.11 ng/mL, demonstrating a sensitivity of 78%, a specificity of 77% and a positive predictive value of 85%. Main limitations of our study are the exploratory design and the criteria adopted for patients' selection determining a detection rate for prostate cancer above the usual range. Leptin only, in our preliminary study, shows promising diagnostic accuracy for the selection of patients candidate to prostate biopsy. Further studies are required to confirm its diagnostic value and its relation with BMI.

  8. Effect of Iron and Carbon Monoxide on Fibrinogenase-like Degradation of Plasmatic Coagulation by Venoms of Six Agkistrodon Species.

    PubMed

    Nielsen, Vance G; Redford, Daniel T; Boyle, Patrick K

    2016-05-01

    Annually, thousands suffer poisonous snakebite, often from defibrinogenating species. It has been demonstrated that iron and carbon monoxide change the ultrastructure of plasma thrombi and improve coagulation kinetics. Thus, this investigation sought to determine whether pre-treatment of plasma with iron and carbon monoxide could attenuate venom-mediated catalysis of fibrinogen obtained from Agkistrodon species with fibrinogenase activity. Human plasma was pre-treated with ferric chloride (0-10 μM) and carbon monoxide-releasing molecule-2 (CORM-2, 0-100 μM) prior to exposure to 0.5-11 μg/ml of six different Agkistrodon species' venom. The amount of venom used for experimentation needed to decrease coagulation function of one or more kinetic parameters by at least 50% of normal values for (e.g. half the normal speed of clot formation). Coagulation kinetics were determined with thrombelastography. All six snake venoms degraded plasmatic coagulation kinetics to a significant extent, especially prolonging the onset to clot formation and diminishing the speed of clot growth. Pre-treatment of plasma with iron and carbon monoxide attenuated these venom-mediated coagulation kinetic changes in a species-specific manner, with some venom effects markedly abrogated while others were only mildly decreased. Further in vitro investigation of other pit viper venoms that possess fibrinogenolytic activity is indicated to identify species amenable to or resistant to iron and carbon monoxide-mediated attenuation of venom-mediated catalysis of fibrinogen. Lastly, future pre-clinical investigation with animal models (e.g. rabbit ear-bleed model) is planned to determine whether iron and carbon monoxide can be used therapeutically after envenomation. © 2015 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  9. Association of socioeconomic stratification with plasmatic markers of lipoperoxidation and antioxidants in Venezuelan school-age children

    PubMed Central

    Bosch, Virgilio; Giacopini, Maria Isabel

    2016-01-01

    Abstract Objetive: To establish association between socioeconomic status and plasmatic markers of lipoperoxidation and antioxidants in Venezuelan school-age children from the middle-class and in critical poverty. Methods: Cross-sectional study with a sample of 114 school-age children (aged 7-9). The socioeconomic status, dietary intake of macro and micro-nutrients, weight, height, lipid profile, indicators of lipid peroxidation and enzymatic and non-enzymatic antioxidants were determined. Results: The daily average intake of energy, carbohydrates and vitamin A, and the percentage of energy obtained from carbohydrates was significantly higher in middle-class children compared to critical poverty children (p <0.05). The circulating oxidized low density lipoprotein (p <0.001) and the susceptibility of low density lipoproteins and very low density lipoproteins to oxidation in vitro (p <0.05) were significantly higher in middle-class children, while the critical poverty children showed significantly lower levels of Vitamin C and E in plasma (p <0.05). Non-enzymatic antioxidant levels were frequently deficient in both strata. The concentrations of circulating oxidized low density lipoprotein (OR: 1.09, CI 95%: 1.016-1.179; p= 0.017) and Vitamin C (OR: 3.21, CI 95%: 1.104-9.938; p= 0.032) were associated to the socioeconomic status independently of gender, family history of premature coronary artery disease, triglicerides, Vitamin C and E dietary intake and count of white blood cells. Conclusion: The socioeconomic status was associated to circulating oxidized low density lipoprotein and Vitamin C in Venezuelan school-age children, The results suggested the need to improve the dietary intake of antioxidants in both studied socioeconomic groups. PMID:28293041

  10. Evolutionary variation of papillomavirus E2 protein and E2 binding sites

    PubMed Central

    2011-01-01

    Background In an effort to identify the evolutionary changes relevant to E2 function, within and between papillomavirus genera, we evaluated the E2 binding sites (E2BS)s inside the long-control-region (LCR), and throughout the genomes. We identified E2BSs in the six largest genera of papillomaviruses: Alpha, Beta, Gamma, Delta, Lambda, and Xi-papillomaviruses (128 genomes), by comparing the sequences with a model consensus we created from known functional E2BSs (HPV16, HPV18, BPV1). We analyzed the sequence conservation and nucleotide content of the 4-nucleotide spacer within E2BSs. We determined that there is a statistically significant difference in GC content of the four-nucleotide E2BS spacer, between Alpha and Delta-papillomaviruses, as compared to each of the other groups. Additionally, we performed multiple alignments of E2 protein sequences using members of each genus in order to identify evolutionary changes within the E2 protein. Results When a phylogenetic tree was generated from E2 amino acid sequences, it was discovered that the alpha-papillomavirus genera segregates into two distinct subgroups (α1 and α2). When these subgroups were individually analyzed, it was determined that the subgroup α1 consensus E2BS favored a spacer of AAAA, whereas subgroup α2 favored the opposite orientation of the same spacer; TTTT. This observation suggests that these conserved inverted linkers could have functional importance. PMID:21806797

  11. Plasmatic concentration of organochlorine lindane acts as metabolic disruptors in HepG2 liver cell line by inducing mitochondrial disorder

    SciTech Connect

    Benarbia, Mohammed el Amine; Macherel, David; Faure, Sébastien; Jacques, Caroline; Andriantsitohaina, Ramaroson; Malthièry, Yves

    2013-10-15

    Lindane (LD) is a persistent environmental pollutant that has been the subject of several toxicological studies. However, concentrations used in most of the reported studies were relatively higher than those found in the blood of the contaminated area residents and effects of low concentrations remain poorly investigated. Moreover, effects on cell metabolism and mitochondrial function of exposure to LD have received little attention. This study was designed to explore the effects of low concentrations of LD on cellular metabolism and mitochondrial function, using the hepatocarcinoma cell line HepG2. Cells were exposed to LD for 24, 48 and 72 h and different parameters linked with mitochondrial regulation and energy metabolism were analyzed. Despite having any impact on cellular viability, exposure to LD at plasmatic concentrations led to an increase of maximal respiratory capacity, complex I activity, intracellular ATP and NO release but decreased uncoupled respiration to ATP synthesis and medium lactate levels. In addition, LD exposure resulted in the upregulation of mitochondrial biogenesis genes. We suggest that, at plasmatic concentrations, LD acts as a metabolic disruptor through impaired mitochondrial function and regulation with an impact on cellular energetic metabolism. In addition, we propose that a cellular assay based on the analysis of mitochondria function, such as described here for LD, may be applicable for larger studies on the effects of low concentrations of xenobiotics, because of the exquisite sensitivity of this organelle. - Highlights: Our data clearly demonstrated in HepG2 cells that exposure at plasmatic low concentrations of LD were able to: • Impair mitochondrial function • Caused alteration on nucleo-mitochondrial cross-talk • Increase nitric oxide release and protein nitration • Impair cellular energetic metabolism and lipid accumulation.

  12. Plasmatic retinol-binding protein 4 and glial fibrillary acidic protein as biomarkers to differentiate ischemic stroke and intracerebral hemorrhage.

    PubMed

    Llombart, Víctor; García-Berrocoso, Teresa; Bustamante, Alejandro; Giralt, Dolors; Rodriguez-Luna, David; Muchada, Marian; Penalba, Anna; Boada, Cristina; Hernández-Guillamon, Mar; Montaner, Joan

    2016-01-01

    A rapid differentiation of acute ischemic stroke and intracerebral hemorrhage (ICH) is essential for an adequate treatment and to promote a better outcome. Our aim was to identify new plasma biomarkers to differentiate stroke subtypes and to combine their diagnostic ability with other biomarkers already described for this clinical indication. Plasma samples of ischemic stroke patients (36) and ICH patients (10) were screened using a 177 antibodies library, and 11 showed different concentrations among stroke subtypes (p < 0.05), mainly chemokines, growth factors and angiogenic factors. Five proteins were selected for replication in 16 ischemic stroke patients and 16 ICH patients, and retinol-binding protein 4 (RPB4), apolipoprotein B100 and pigment epithelial-derived factor were replicated (p < 0.05). These proteins, together with glial fibrillary acidic protein (GFAP) and receptor for advanced glycation end product, were tested in 38 ischemic stroke and 28 ICH samples. Finally, RBP4 >61 μg/mL and GFAP <0.07 ng/mL showed a specificity of 100% for both subtypes. Moreover, after multivariate logistic regression analysis, RBP4 >48.75 μg/mL (ORadj : 6.09 (1.3-28.57), p = 0.02) and GFAP <0.07 ng/mL (ORadj : 0.03 (0.003-0.31), p = 0.003) resulted in independent predictors of stroke subtype, improving discrimination by 29% (p < 0.0001). Both biomarkers might be useful as diagnostic biomarkers to differentiate ischemic stroke and ICH. A rapid differentiation of ischemic stroke from intracerebral hemorrhage is essential to provide the appropriate treatment. We describe the discovery and subsequent replications of RBP4 and its combination with circulating GFAP as plasmatic biomarkers for hyperacute stroke subtype differentiation. The combination of these biomarkers and others might aid to speed up the discrimination of both stroke subtypes improving the outcome of patients.

  13. The Astro-E2 Mission

    NASA Technical Reports Server (NTRS)

    Kelley, Richard L.

    2004-01-01

    The Astro-E2 observatory is a rebuild of the original Astro-E observatory that was lost during launch in February 2000. It is scheduled for launch into low earth orbit on a Japanese M-V rocket in early 2005. The Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, is developing the observatory with major contributions from the US. The three instruments on the observatory are the high-resolution x-ray spectrometer (the XRS) featuring a 30-pixel x-ray microcalorimeter array, a set of four CCD cameras (the XIS) and a combination photo-diode/scintillator detector system (the HXD) that will extend the band pass up to nearly 700 keV. A significant feature of Astro-E2 is that all of the instruments are coaligned and operated simultaneously. With its high spectral resolution and collecting area for spectroscopy above 1 keV, Astro-E2 should enable major discovery space and pioneer new technology for use in space. Prime areas for investigation are supernova remnants, active galaxies and the measurement of black hole properties via relativistically-broadened Fe-K emission galaxies. A number of enhancements have been made for the Astro-E2/XRS, including a higher resolution microcalorimeter array, ii mechanical cooler for longer cryogen life, and an improved in-flight calibration system. The Astro-E2/XIS has also been improved to include two back-side-illuminated CCDs to enhance the low energy response. Improvements have also been made to the x-ray mirrors used for both the XRS and XIS to sharpen the point spread function and reduce the effects of stray light. In this talk we will present the essential features of Astro-E2, paying particular attention to the enhancements, and describe the major scientific strengths of the observatory.

  14. Overexpression of E2F5/p130, but not E2F5 alone, can inhibit E2F-induced cell cycle entry in transgenic mice.

    PubMed

    Chen, Qin; Liang, Dongcai; Overbeek, Paul A

    2008-03-25

    The retinoblastoma (Rb) gene family member p130 binds preferentially to the E2F5 transcription factor and forms a repressive E2F5/p130 complex that inhibits cell cycle progression and tumor growth. It is unclear whether E2F5, either alone or in combination with p130, can interfere with the transcriptional activity of other E2F family members, such as E2F1 and E2F3a, in vivo. In this study, we used transgenic mice to test whether overexpression of E2F5 with/without p130 would be sufficient to inhibit E2F1 or E2F3a induced cell cycle reentry. Transgenic mice were generated by microinjection of constructs containing different E2F cDNAs (E2F1, E2F3a, and E2F5) or the p130 cDNA linked to the mouse alphaA-crystallin promoter. The E2F5 single and E2F5/p130 double transgenic mice were cross-mated with E2F1 or E2F3a transgenic mice. The resulting double or triple transgenic mouse embryos were characterized by histology, in situ hybridization, immunohistochemistry, and BrdU incorporation assays. Overexpression of E2F5 alone was not sufficient to inhibit E2F1 or E2F3a induced cell cycle reentry in lens fiber cells. Transgenic mice coexpressing E2F5 and p130 in lens fiber cells did not show lens defects. However, coexpression of E2F5/p130 with E2F1 or E2F3a in lens fiber cells decreased the number of BrdU positive fiber cells induced by the E2F1 or E2F3a alone. Therefore, overexpression of E2F5/p130, but not E2F5 alone, can inhibit activator E2F-mediated cell proliferation in vivo, confirming that p130 plays a critical role in the repressive activity of E2F5/p130 complex. Overexpression of E2F5/p130 in post-mitotic lens fiber cells does not affect their normal differentiation program, but can inhibit inappropriate cell cycle reentry induced by the activator E2Fs. Since E2F5 alone cannot interfere with these E2F activities, we conclude that p130 is a key player in the inhibitory process.

  15. Changes in the expression of α1B-adrenoceptor in peripheral mononuclear cells correlates with blood pressure and plasmatic homocysteine.

    PubMed

    Oliver, Eduardo; Montó, Fermí; Rovira, Eduardo; Valldecabres, Carmen; Muedra, Vicente; D'Ocon, Pilar

    2017-04-01

    Human peripheral mononuclear cells (HPMC) have been suggested as a practical surrogate for myocardial or vascular cells. Present work analyses if changes in the expression of α1-adrenoceptors (ARs) in HPMC are related to the hypertensive state and its clinical consequences. Quantitative RT-PCR was employed to evaluate the mRNA levels of the three α1-ARs (α1A, α1B, α1D) in HPMC isolated from normotensive and hypertensive patients, and also in tissues from two animal models of hypertension: spontaneously hypertensive rats (SHR) and hypertension induced by chronic treatment with L-NAME. In patients, 24-h ambulatory blood pressure and serum biochemical profile were also recorded. We found that α1B-AR expression was higher in HPMC from hypertensive patients and correlated with blood pressure and plasmatic homocysteine. A rise in the α1B-AR expression in kidneys, but not in heart from hypertensive animal models was also found. α1D-AR did not change in HPMC, not in rat heart or kidney, but a significant correlation with plasmatic aldosterone was found. In conclusion, we have proved that α1-ARs mRNA expression in HPMC correlates with clinical variables and could be used as a potential biomarker in hypertensive patients.

  16. E2E: A Summary of the e2e Learning Framework.

    ERIC Educational Resources Information Center

    Learning and Skills Development Agency, London (England).

    This publication is a summary of the E2E (Entry to Employment) Learning Framework that provides guidance on program implementation. (E2E is a new learning program for young people not yet ready or able to enter Modern Apprenticeship programs, a Level 2 program, or employment directly.) Section 2 highlights core values to which all involved should…

  17. E2F-4 and E2F-5, two members of the E2F family, are expressed in the early phases of the cell cycle.

    PubMed Central

    Sardet, C; Vidal, M; Cobrinik, D; Geng, Y; Onufryk, C; Chen, A; Weinberg, R A

    1995-01-01

    The E2F transcription factors play a role in regulating the expression of genes required for cell proliferation. Their activity appears to be regulated by association with the retinoblastoma protein (pRb) and the pRb-related proteins p107 and p130. In vivo, pRb is found in complex with a subset of E2F components--namely, E2F-1, E2F-2, and E2F-3. Here we describe the characterization of cDNAs encoding two unusual E2Fs, E2F-4 and E2F-5, each identified by the ability of their gene product to interact with p130 in a yeast two-hybrid system. E2F-4 and -5 share common sequences with E2F-1, E2F-2, and E2F-3 and, like these other E2Fs, the ability to heterodimerize with DP-1, thereby acquiring the ability to bind an E2F DNA recognition sequence with high affinity. However, in contrast to E2F-1, E2F-4 and E2F-5 fail to bind pRb in a two-hybrid assay. Moreover, they show a unique pattern of expression in synchronized human keratinocytes: E2F-4 and E2F-5 mRNA expression is maximal in mid-G1 phase before E2F-1 expression is detectable. These findings suggest that E2F-4 and E2F-5 may contribute to the regulation of early G1 events including the G0/G1 transition. Images Fig. 2 Fig. 3 Fig. 4 PMID:7892279

  18. Bioassays for estrogenic activity: development and validation of estrogen receptor (ERalpha/ERbeta) and breast cancer proliferation bioassays to measure serum estrogenic activity in clinical studies.

    PubMed

    Li, J; Lee, L; Gong, Y; Shen, P; Wong, S P; Wise, Stephen D; Yong, E L

    2009-02-01

    Standard estrogenic prodrugs such as estradiol valerate (E2V) and increasingly popular phytoestrogen formulations are commonly prescribed to improve menopausal health. These drugs are metabolized to numerous bioactive compounds, known or unknown, which may exert combinatorial estrogenic effects in vivo. The aim of this study is to develop and validate estrogen receptor (ER) alpha/ERbeta reporter gene and MCF-7 breast cancer cell proliferation bioassays to quantify serum estrogenic activities in a clinical trial setting. We measured changes in serum estrogenicity following ingestion of E2V and compared this to mass spectrometric measurements of its bioactive metabolites, estrone and 17beta-stradiol. ERalpha bioactivity of the 192 serum samples correlated well (R = 79%) with 17beta-estradiol levels, and adding estrone improved R to 0.83 (likelihood ratio test, P < 0.0001), suggesting that the ERalpha assay reflects summated activity of compounds in serum. ERbeta correlated moderately (R = 0.52) with estrone and 17beta-estradiol, with an estrone/17beta-estradiol coefficient ratio that was twice that of ERalpha, indicating estrone was more active on a molar basis in the ERbeta assay. Unlike the ERalpha and ERbeta bioassays, MCF-7 cell proliferation was driven by 17beta-estradiol, and addition of estrone did not increase the predictive value of the model, suggesting that the driver or drivers for breast cancer cell proliferation were not the same as for ERalpha and ERbeta transactivation. In contrast, a decoction of the traditional Chinese medicinal herb Epimedium pubescens did not induce significant changes in estrogenic bioactivity over baseline. These data indicate that ERalpha/ERbeta reporter gene and MCF-7 breast cancer cell proliferation bioassays reflect different aspects of estrogenic activity and that these assays suggest that the Epimedium formulation tested is unlikely to exert significant estrogenic effects in humans.

  19. Ultrafast Electron Pulse (e,2e) Processes

    NASA Astrophysics Data System (ADS)

    Shao, Hua-Chieh; Starace, Anthony; Madsen, Lars

    2012-06-01

    Techniques for producing ultrafast electron pulses have been proposedootnotetextP. Baum and A.H. Zewail, Proc. Natl. Acad. Sci. U.S.A. 104, 18409 (2007); S.A. Hilbert, C. Ulterwaal, B. Barwick, H. Betalaan, and A.H. Zewail, ibid. 106, 10558 (2009). and prospects for using such pulses to image electron dynamics in the H atom and the hydrogen molecular ion have been theoretically demonstrated.ootnotetextH.-C. Shao and A.F. Starace, Phys. Rev. Lett. 105, 263201 (2010). The (e,2e) process provides a means to directly image the momentum distribution of the target.ootnotetextM.A. Coplan, J.H. Moore, and J.P. Doering, Rev. Mod. Phys. 66, 985 (1994). We explore here the possibility of observing the time dependence of a coherent superposition of target orbitals by means of the (e,2e) process with ultrafast incident electron pulses. Using scattering theory for a longitudinally coherent beam,ootnotetextF. Robicheaux, Phys. Rev. A 62, 062706 (2000). we find that the momentum distribution of a coherent state of the H atom can be retrieved.

  20. Effect of tomato juice consumption on the plasmatic lipid profile, hepatic HMGCR activity, and fecal short chain fatty acid content of rats.

    PubMed

    Periago, María Jesús; Martín-Pozuelo, Gala; González-Barrio, Rocío; Santaella, Marina; Gómez, Victoria; Vázquez, Nuria; Navarro-González, Inmaculada; García-Alonso, Javier

    2016-10-12

    The aims of the present study were to ascertain, indirectly, the prebiotic role of tomato juice, by analyzing its effect on the content of short chain fatty acids (SCFA) in feces of rats, and to determine the plausible mechanisms related to the hypocholesterolemic effects of tomato juice and lycopene, evaluating the activity of hepatic HMGCR and the formation of propionic acid. Two commercially available tomato juices with differing contents of lycopene (low and high lycopene contents: Llyc and Hlyc tomato juices) were used. Sprague-Dawley male rats were randomly divided into three experimental groups (n = 8): control group, normal diet and water; group 1, normal diet and Llyc tomato juice; and group 2, normal diet and Hlyc tomato juice, which were fed ad libitum for three weeks. Feces were collected at the beginning and the end of the study to determine SCFA, and blood and liver were obtained (after sacrificing the animals) to analyze the lipid plasmatic parameters and the HMGCR activity and total cholesterol, respectively. No significant differences were observed in the plasmatic parameters, except that HDL-cholesterol increased significantly after consumption of both tomato juices. Lycopene was accumulated in the liver in proportion to the amount ingested, and was observed to have an inhibitory effect on the HMGCR enzyme, according to the amount of lycopene in the liver. In relation to the SCFA in feces, no differences were observed in acetate and propionate after the consumption of tomato juice, but a significant increase in butyrate was observed in group 2 after the intake of Hlyc tomato juice. The content of this carboxylic acid together with excreted lycopene in feces could have a beneficial effect on colonic cells.

  1. The association between detectable plasmatic human immunodeficiency virus (HIV) viral load and different subgingival microorganisms in Brazilian adults with HIV: a multilevel analysis.

    PubMed

    Pereira, Viviane Tiago; Pavan, Priscila; Souza, Rodrigo Carvalho; Souto, Renata; Vettore, Mario Vianna; Torres, Sandra Regina; Colombo, Ana Paula Vieira; de Uzeda, Milton; Sansone, Carmelo; Gonçalves, Lucio Souza

    2014-05-01

    This study investigates the association between detectable plasmatic human immunodeficiency virus (HIV) viral load (HVL) and high levels of periodontal- and non-periodontal-related microorganisms in the subgingival microbiota of individuals with HIV. Thirty-seven individuals with HIV were divided into two groups: 1) detectable HVL (n = 15); and 2) undetectable HVL (n = 22). Subgingival biofilm samples were obtained, and the levels of 35 microbial species were determined by the checkerboard DNA-DNA hybridization method. Periodontal clinical measures and laboratory and sociodemographic data were also registered. χ(2) test, Fisher exact test, and Mann-Whitney U test were used to compare groups. Multilevel ordinal regression models were used to test the association between HVL and the levels of 35 microbial species in subgingival biofilm, adjusted for confounders. Of the 35 species studied, 11 (31.4%) showed higher mean levels in the detectable HVL group than undetectable HVL group (P <0.001). These species included Actinomyces naeslundii II, Actinomyces israelii, Actinomyces odontolyticus, Veillonella parvula, Capnocytophaga gingivalis, Eikenella corrodens, Campylobacter concisus, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Candida albicans. Significant associations between detectable HVL and high levels of microorganisms, adjusted for confounders, were observed for A. naeslundii I, Actinomyces gerencseriae, C. gingivalis, E. corrodens, C. concisus, Prevotella nigrescens, T. forsythia, and Dialister pneumosintes. Detectable plasmatic HVL in individuals with HIV was associated with elevated levels of known periodontal pathogens, such as P. nigrescens, T. forsythia, and E. corrodens, as well as C. concisus, C. gingivalis, and D. pneumosintes in the subgingival biofilm.

  2. Promising roles of mammalian E2Fs in hepatocellular carcinoma.

    PubMed

    Zhan, Lei; Huang, Cheng; Meng, Xiao Ming; Song, Yang; Wu, Xiao Qin; Miu, Cheng Gui; Zhan, Xiang Shu; Li, Jun

    2014-05-01

    In mammalian cells, E2F family of transcription factors (E2Fs) traditionally modulates assorted cellular functions related to cell cycle progression, proliferation, apoptosis and differentiation. Eight members, E2F1 E2F8 have been recognized of this family so far, and the members of this family are generally divided into activator E2F (E2F1--E2F3a), repressor E2F (E2F3b--E2F5) and inhibitor E2F (E2F6--E2F8) subclasses based on their structur-e and function. Studies have showed that the mammalian E2F family members represent a recent evolutionary adaptation to malignancies besides hepatocellular carcinoma (HCC), and a growing body of evidence has validated that the individual members of the family develop a close relationship with HCC. E2F1 was identified to play overlapping roles in HCC, while E2F2--E2F8 (except E2F6 and E2F7) showed to be tumor-promoter in HCC. However, the mechanism underlying the mammalian E2Fs associated with HCC is still unknown and needs further research. The aim of this review is to sum up the collective knowledge of E2F family and the roles of each member of this family in HCC. Moreover, we will discuss some novel therapeutic target for HCC based on the complicated functions of mammalian E2Fs. Copyright © 2014. Published by Elsevier Inc.

  3. Cell cycle analysis of E2F in primary human T cells reveals novel E2F complexes and biochemically distinct forms of free E2F.

    PubMed Central

    Chittenden, T; Livingston, D M; DeCaprio, J A

    1993-01-01

    The transcription factor E2F activates the expression of multiple genes involved in cell proliferation, such as c-myc and the dihydrofolate reductase gene. Regulation of E2F involves its interactions with other cellular proteins, including the retinoblastoma protein (Rb), the Rb-related protein p107, cyclin A, and cdk2. We undertook a detailed analysis of E2F DNA-binding activities and their cell cycle behavior in primary human T cells. Three E2F DNA-binding activities were identified in resting (G0) T cells with mobilities in gel shift assays distinct from those of previously defined E2F complexes. One of these activities was found to be a novel, less abundant, Rb-E2F complex. The most prominent E2F activity in resting T cells (termed complex X) was abundant in both G0 and G1 but disappeared as cells entered S phase, suggesting a possible role in negatively regulating E2F function. Complex X could be dissociated by adenovirus E1A with a requirement for an intact E1A conserved region 2. However, X failed to react with a variety of antibodies against Rb or p107, implicating the involvement of an E1A-binding protein other than Rb or p107. In addition to these novel E2F complexes, three distinct forms of unbound (free) E2F were resolved in gel shift experiments. These species showed different cell cycle kinetics. UV cross-linking experiments suggested that a distinct E2F DNA-binding protein is uniquely associated with the S-phase p107 complex and is not associated with Rb. Together, these results suggest that E2F consists of multiple, biochemically distinct DNA-binding proteins which function at different points in the cell cycle. Images PMID:8321204

  4. Inactivation of E2F3 results in centrosome amplification.

    PubMed

    Saavedra, Harold I; Maiti, Baidehi; Timmers, Cynthia; Altura, Rachel; Tokuyama, Yukari; Fukasawa, Kenji; Leone, Gustavo

    2003-04-01

    The E2F family of transcription factors is critical for the control of cell cycle progression. We now show that the specific inactivation of E2F3 in mouse embryo fibroblasts (MEFs) results in a disruption of the centrosome duplication cycle. Loss of E2F3, but not E2F1, E2F2, E2F4, or E2F5 results in unregulated cyclin E-dependent kinase activity, defects in nucleophosmin B association with centrosomes, and premature centriole separation and duplication. Consequently, this defect leads to centrosome amplification, mitotic spindle defects, and aneuploidy. Our findings implicate the E2F3 transcription factor as an important link that orchestrates DNA and centrosome duplication cycles, ensuring the faithful transmission of genetic material to daughter cells.

  5. Study of the influence of laser of low potency to label red blood cells and plasmatic protein with 99mTc in vitro

    NASA Astrophysics Data System (ADS)

    Rolim, Ricardo Q.; Carvalho, Elaine F.; Nascimento, Edgar V.; Souza, Grace M.; Magnata, Simey S.; Bernardo-Filho, Mario; Catanho, Maria T.

    2004-09-01

    This work aims to verify the effect of laser of low potency to label red blood cells and plasmatic protein with 99mTc in vitro. The experiments were carried out by incubating of anticoagulant whole blood. Differents doses of gallium arsenide laser with energy density of 3j/cm2, 6j/cm2, 9 j/cm2, 18 j/cm2 and 804nm wavelength was applied. A stannous chloride solution of 1,2μg/mL was added the incubation for 60 minutes. After this the 99mTc was added and the incubation was continued for another 10 minutes. Those were centrifuged, precipitated with thrichoroacetic acid 5% and mensured in a counter. The results shows that there is a significant decrease in the fixation of 99mTc in red blood cells when the concentration of 3j/ cm2 and (from 93 to 32.2%) and in occurs an increase %ATI from 12 to 54,6% of plasma protein. The laser promote modification on some properties of the red blood cellular membrane, probably, due to the metabolization of cellular that could be capable to generation the active metabolites.

  6. Effect of training judo in the competition period on the plasmatic levels of leptin and pro-inflammatory cytokines in high-performance male athletes.

    PubMed

    de Oliveira, Donizete Cicero Xavier; Rossano Procida, Izildinha; das Neves Borges-Silva, Cristina

    2010-06-01

    The purpose this study was to evaluate the effect of training judo in the competition period on the plasmatic levels of bioactive molecules in high-performance male athletes. The subjects were divided into two groups, a trained group with 11 judokas and a nontrained group also with 11 subjects. Blood samples obtained 60 h after training to measure plasma tumor necrosis factor (TNF-alpha), interleukin-6 (IL-6), monocyte chemotactic protein 1 (MCP-1), and leptin levels. The trained group presented a significant reduction in the percentage of fat and fat mass and an increase in the lumbar and lower limbs traction forces and the maximum VO(2) when compared to the nontrained group. There was no significant difference in the serum concentrations of TNF-alpha and IL-6 between the two groups. The trained group presented a lower concentration of leptin, both as absolute values as well as relative to the percentage of fat, and a higher concentration of MCP-1, in relation to the nontrained group. Our results suggest an adaptation in the capacity of synthesizing and secreting leptin in response to chronic stress in judo, what suggests a neuro-hormonal adjustment that guarantees the efficiency of metabolism. The changes of MCP-1 indicated a possible inflammatory state.

  7. Mediterranean diets supplemented with virgin olive oil and nuts enhance plasmatic antioxidant capabilities and decrease xanthine oxidase activity in people with metabolic syndrome: The PREDIMED study.

    PubMed

    Sureda, Antoni; Bibiloni, Maria Del Mar; Martorell, Miquel; Buil-Cosiales, Pilar; Marti, Amelia; Pons, Antoni; Tur, Josep A; Martinez-Gonzalez, Miguel Ángel

    2016-12-01

    This study assessed plasmatic antioxidant capabilities and xanthine oxidase (XOX) activity in metabolic syndrome patients after 5 years intervention with Mediterranean diet (MeDiet) supplemented with extra-virgin olive oil or with nuts or with low-fat diet (the PREDIMED [PREvención con Dieta MEDiterránea] study). Seventy-five participants were randomly selected. Daily energy and nutrient intake were assessed with a validated 137-item food frequency questionnaire, and adherence to the MeDiet was assessed using a 14-item questionnaire. Catalase, superoxide dismutase (SOD), myeloperoxidase, XOX activities and protein levels, and protein carbonyl derivatives, nitrotyrosine, nitrite and nitrate levels were determined in overnight fasting venous blood samples. The plasma activity and protein levels of SOD and catalase were significantly higher and XOX activity was lower in MeDiet supplemented with extra-virgin olive oil and MeDiet supplemented with nuts than in the control group. Participants in both MeDiet groups showed higher plasma nitrate levels than in the control group. Adherence to the MeDiet showed a positive correlation with SOD and catalase plasma antioxidant activities. A MeDiet enriched with either virgin olive oil or nuts enhances the plasma antioxidant capabilities and decreases XOX activity in patients with the metabolic syndrome but we did not observe changes in myeloperoxidase or markers of oxidative damage. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. E2 transitions in deformed nuclei and the IBA

    SciTech Connect

    Warner, D.D.; Casten, R.F.

    1981-01-01

    The mechanism which determines the relative E2 strengths in the Interacting Boson Approximation is studied, and the structure of the E2 operator necessary to reproduce the empirical B(E2) values in deformed even-even nuclei in the rate earth region is investigated. (WHK)

  9. 26 CFR 1.503(e)-2 - Requirements.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 7 2013-04-01 2013-04-01 false Requirements. 1.503(e)-2 Section 1.503(e)-2...) INCOME TAXES (CONTINUED) Exempt Organizations § 1.503(e)-2 Requirements. (a) In general. The requirements... price may not be a valid price for 1,000 bonds and the purchase may therefore not meet the requirements...

  10. 26 CFR 1.503(e)-2 - Requirements.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 7 2014-04-01 2013-04-01 true Requirements. 1.503(e)-2 Section 1.503(e)-2...) INCOME TAXES (CONTINUED) Exempt Organizations § 1.503(e)-2 Requirements. (a) In general. The requirements... price may not be a valid price for 1,000 bonds and the purchase may therefore not meet the requirements...

  11. 26 CFR 1.503(e)-2 - Requirements.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 7 2011-04-01 2009-04-01 true Requirements. 1.503(e)-2 Section 1.503(e)-2...) INCOME TAXES (CONTINUED) Exempt Organizations § 1.503(e)-2 Requirements. (a) In general. The requirements... price may not be a valid price for 1,000 bonds and the purchase may therefore not meet the requirements...

  12. [Effect of the supplementation of vitamins B12, B6 and folic acid on homocysteine and plasmatic lipids in patients with hyperlipoproteinemic secondary type IV].

    PubMed

    Morón de Salim, Alba Rosa; Garcés Pasamontes, Antonio

    2005-03-01

    The cases of hyperlipoproteinemic secondary type IV are manifested by elevation of triglycerides, with normal or high cholesterol and lightly high homocysteine. The effect of vitamins B12, B6 and folic acid, on homocysteine and lipids, in 24 male patients, 35-68 years, with hiperlipoproteinemia secondary type IV with myocardial isquemic, and without previous treatment of hipolipemiant, was investigated. The patients were supplemented with therapeutic doses tablets of vitamin B12, 500 (microg/day); B6, (600 mg/day) and folic acid (20 mg/ day), during 120 days. Homocysteine, triglycerides, total and fractional cholesterol, at (basal), 30, 60, 90 and 120 days, were determined. Descriptive statistical analyses were applied, coefficient of correlation of Pearson and proves of "t", with a p < 0.005; the data were processed by statistical program SPSS version 8.0. The results showed a decrease in the levels of homocysteine from basal 17.1 +/- 0.7 micromol/L to 13.18 +/- 0.83 micromol/L, at the end of experimental period. The triglycerides (TG), total cholesterol (TC), low density lipoprotein (LDL), very low density lipoprotein (VLDL) showed a reduction of (21.8 mg/dl; 8.5 mg/dl; 5.87 mg/dl; respectively) for every pmol/L of reduced homocysteine, with (p < 0.001) for triglycerides. High density lipoprotein (HDL) increased 1.1 mg/dl and coronary risk descent in 24%. We concluded that therapeutic doses of vitamins B12, B6 and folic acid, may is effective in decreased plasmatic homocysteine levels and lipids, mainly triglycerides, with a reduction of coronary risk, to these type of patients, with not collateral effects of neuropathy

  13. Mice Survival and Plasmatic Cytokine Secretion in a “Two Hit” Model of Sepsis Depend on Intratracheal Pseudomonas Aeruginosa Bacterial Load

    PubMed Central

    Restagno, Damien; Venet, Fabienne; Paquet, Christian; Freyburger, Ludovic; Allaouchiche, Bernard; Monneret, Guillaume; Bonnet, Jeanne-Marie; Louzier, Vanessa

    2016-01-01

    Sepsis is characterized by pro- and anti-inflammatory responses following infection. While inflammation is responsible for widespread organ damage, anti-inflammatory mediators lead to immunoparalysis increasing susceptibility to secondary infections (nosocomial pneumonia). We aimed to investigate the impact of bacterial load on survival and cytokine release in a two-hit murine (C57BL/6J) model of CLP followed by P. aeruginosa pneumonia. Plasmatic TNFα, IL-6, IL-10, sTNFr I and II were quantified until 13 days. At D5, splenocytes were processed for immunological assays or mice were intratracheally instilled with Pseudomonas aeruginosa (5.106, 2.107 and 108 CFU) to evaluate survival and cytokines production. TNFα, sTNFrs, IL-6 and IL-10 increased 2h post CLP. TNFα and sTNFrs declined respectively one and two days later. In CLP mice, IL-6 and IL-10 remained high for the whole experiment, as compared to Sham. At D5, for CLP mice, whereas total T cells population (CD3+) decreased, Treg fraction (CD4+/CD25+) increased. In parallel, T cells proliferation and LPS-stimulated splenocytes ability to release TNFα decreased. At D13, survival was 100% after 5.106 CFU, 50% for CLP mice after 2.107 CFU and 0% for CLP and Sham after 108 CFU. After instillation, IL-10 and IL-6 increased and appeared to be dose and time dependent. Pseudomonas was detected in all CLP and Sham’s lungs; in spleen and liver only in CLP at 2.107 CFU, and in CLP and Sham at 108 CFU. We demonstrated that post-CLP immunosuppression followed by Pseudomonas aeruginosa lung instillation increases mortality reactivates cytokines secretion and is associated with systemic dissemination in septic mice depending on bacterial load. PMID:27574993

  14. E2F1 — EDRN Public Portal

    Cancer.gov

    The E2F1 protein belongs to the E2F/DP family of transcription factors. E2F1 binds DNA cooperatively with dp (differentiation regulated transcription factor proteins)proteins through the E2 recognition site, 5'-TTTC[CG]CGC-3' found in the promoter region of a number of genes whose products are involved in cell cycle regulation or in DNA replication. The E2F family plays a crucial role in the control of cell cycle and action of tumor suppressor proteins and is also a target of the transforming proteins of small DNA tumor viruses. E2F1 can mediate both cell proliferation and p53-dependent/independent apoptosis.

  15. Involvement of E2F transcription factor family in cancer.

    PubMed

    Tsantoulis, P K; Gorgoulis, V G

    2005-11-01

    The E2F family of transcription factors is a central modulator of important cellular events, including cell cycle progression, apoptosis and DNA damage response. The role of E2F family members in various human malignancies is yet unclear and may provide vital clues to the diagnosis, prognosis and therapy of cancer patients. In this review we provide a brief but concise overview of E2F function and its putative role in the most common human tumour types.

  16. Mechanism and Product Distribution of the O3-Initiated Degradation of (E)-2-Heptenal, (E)-2-Octenal, and (E)-2-Nonenal.

    PubMed

    Gaona Colmán, Elizabeth; Blanco, María B; Barnes, Ian; Wiesen, Peter; Teruel, Mariano A

    2017-07-13

    The O3-molecule initiated degradation of three 2-alkenals (E)-2-heptenal, (E)-2-octenal, and (E)-2-nonenal has been investigated in a 1080 L quartz-glass environmental chamber at 298 ± 2 K and atmospheric pressure of synthetic air using in situ FTIR spectroscopy to monitor the reactants and products. The experiments were performed in the absence of an OH scavenger. The molar yields of the primary products formed were glyoxal (49 ± 4) % and pentanal (34 ± 3) % from the reaction of (E)-2-heptenal with O3, glyoxal (41 ± 3) % and hexanal (39 ± 3) % from the reaction of (E)-2-octenal with O3, and glyoxal (45 ± 3) % and heptanal (46 ± 3) % from the reaction of (E)-2-nonenal with O3. The residual bands in the infrared product spectra for each of the studied reactions are attributed to 2-oxoaldehyde compounds. Based on the observed products, a general mechanism for the ozonolysis reaction of long chain unsaturated aldehydes is proposed, and the results are compared with the available literature data.

  17. Cooperative DNA binding of the bovine papillomavirus E2 transcriptional activator is antagonized by truncated E2 polypeptides.

    PubMed Central

    Monini, P; Blitz, I L; Cassai, E

    1993-01-01

    Cooperative DNA binding of the bovine papillomavirus type 1 (BPV-1) E2 transcriptional activator (E2-TA) is thought to play a role in the transcriptional synergism of multiple E2-responsive DNA elements (J. Ham, N. Dostatni, J.-M. Gauthier, and M. Yaniv, Trends Biochem. Sci. 16:440-444, 1991). Binding-equilibrium considerations show that such involvement is unlikely, thereby suggesting that the E2-TA cooperative capacity may have evolved to play other, different roles. The role of cooperative interactions in the antagonistic activity of BPV-1-positive and BPV-1-negative E2 regulatory proteins was investigated by an in vitro quantitative gel shift assay. Viral repressor E2-TR, a truncated peptide encompassing the activator DNA-binding domain, possesses a small but measurable cooperative capacity. Furthermore, the minimal E2 DNA-binding domain interacts with the activator in a positive, heterocooperative manner. As a result, the in vitro competition of full-length and truncated E2 peptides appears to be (macroscopically) noncooperative. This heterocooperative effect is probably dominant in latently infected G0-G1 cells, in which repressor E2-TR is 10- to 20-fold more abundant than the activator. The data are discussed considering the possible role of homo- and heterocooperative DNA binding in E2-conditional gene expression. Images PMID:8394466

  18. Highly anomalous yrast B ( E2 ) values and vibrational collectivity

    NASA Astrophysics Data System (ADS)

    Cakirli, R. B.; Casten, R. F.; Jolie, J.; Warr, N.

    2004-10-01

    It is shown that the existing yrast B ( E2 ) values [especially the B ( E2; 4+1 → 2+1 ) /B ( E2; 2+1 → 0+1 ) ratio] in 98 Ru are highly anomalous and cannot be plausibly interpreted with existing models. A survey of all even-even nuclei from 40⩽Z⩽80 shows that this phenomenon is rare in collective nuclei. It occurs to a much lesser extent in 114 Te , 114 Xe , and possibly a few other nuclides. The combination of vibrational-like energies and nonvibrational B ( E2 ) values perhaps points to a different kind of vibrational behavior.

  19. Morphometric analysis of prostates in castrated dogs after treatment with androstanediol, estradiol, and cyproterone acetate.

    PubMed

    Tunn, U W; Schüring, B; Senge, T; Neumann, F; Schweikert, H U; Rohr, H P

    1981-01-01

    We studied the prostates of 22 beagle dogs by light morphometric analysis under defined hormonal influences. Prostatic weight increased with 3 alpha-androstanediol (3 alpha-diol) alone and in combination with 17 beta-estradiol (E2). Two different prostatic hyperplasia models were established. 3 alpha-Diol brings about diffuse glandular prostatic hyperplasia with an absolute increase of glandular parenchyma and, together with E2, provokes stromal hyperplasia with squamous metaplasia of the epithelium and secondary cyst formation. In both models, the antiandrogen cyproterone acetate causes a significant reduction of the absolute and relative volumes of the glandular compartment with antiandrogenic effects on the stroma.

  20. Effect of estrogen on egg production, shell quality and calcium metabolism in molted hens.

    PubMed

    Qin, X; Klandorf, H

    1995-01-01

    Force-molted White Leghorn laying hens were implanted with 0.25, 0.5, 1 and 3 Compudose 200 pellets (24 mg 17 beta estradiol/pellet). Plasma estradiol increased with increasing E2 dosages in a linear manner and decreased over time in a quadratic manner (P < 0.01). E2 treatment had a nonlinear effect on total plasma calcium. Oviduct weight, shell thickness and egg weight were not significantly affected by exogenous estradiol whereas tibial bone ash percentage was increased at only one dose (P < 0.05:0.5 pellet group). Physiological supplementation with estradiol does not improve shell quality.

  1. Common Importin Alpha Specificity for Papillomavirus E2 Proteins

    PubMed Central

    Bian, Xue-lin; Wilson, Van G.

    2010-01-01

    Papillomaviruses infected keratinocytes and their reproduction is tied to differentiation of the skin. The E2 protein of papillomaviruses is a multifunctional early protein that binds specifically to the viral DNA to regulate genome transcription, replication, and segregation. All of these are nuclear events that require specific transport of E2 into the host nucleus. Nuclear localization signal (NLS) sequences have been mapped for several E2 proteins, and these sequences resemble motifs that interact with cellular transport adaptor molecules termed alpha importins. To determine which importins could carry E2 proteins, in vitro binding studies were performed with three different E2 proteins and the five ubiquitous alpha importins. The E2 proteins preferentially interacted with alpha importins 3 and 5, and showed very weak or no interaction with the other three widely expressed alpha importins (α1, α4, and α7). While all five alpha importins appear to be constitutively expressed in keratinocytes, during differentiation of a human keratinocyte line (HaCaT) we observed a specific increase in expression of alphas 3 and 5. This differentiation-specific increase in α3 and α5 expression suggests that preferential usage of these two importins by E2 may facilitate E2 nuclear uptake during terminal differentiation. PMID:20193720

  2. The RB-E2F1 Pathway Regulates Autophagy

    PubMed Central

    Jiang, Hong; Martin, Vanesa; Gomez-Manzano, Candelaria; Johnson, David G.; Alonso, Marta; White, Erin; Xu, Jing; McDonnell, Timothy J.; Shinojima, Naoki; Fueyo, Juan

    2011-01-01

    Autophagy is a protective mechanism that renders cells viable in stressful conditions. Emerging evidence suggests that this cellular process is also a tumor suppressor pathway. Previous studies showed that cyclin-dependent kinase inhibitors (CDKI) induce autophagy. Whether retinoblastoma protein (RB), a key tumor suppressor and downstream target of CDKIs, induces autophagy is not clear. Here, we show that RB triggers autophagy and that the RB activators p16INK4a and p27/kip1 induce autophagy in an RB-dependent manner. RB binding to E2 transcription factor (E2F) is required for autophagy induction and E2F1 antagonizes RB-induced autophagy, leading to apoptosis. Downregulation of E2F1 in cells results in high levels of autophagy. Our findings indicate that RB induces autophagy by repressing E2F1 activity. We speculate that this newly discovered aspect of RB function is relevant to cancer development and therapy. PMID:20807803

  3. Plasmatic markers in hemorrhagic stroke.

    PubMed

    Marginean, I C; Stanca, D M; Vacaras, V; Soritau, O; Margiean, M; Muresanu, D F

    2011-05-15

    Stroke is the third most common cause of death in the United States and it is the leading cause of disability. Early diagnosis and immediate therapeutic interventions are important factors to reduce the extent of brain tissue damage and the risk of stroke-related death. A rapid blood test that can confirm the clinical or imaging diagnosis or that can add to the stratification of the risk would be very useful. Such a test has to be validated in large studies and has to be based on a simple and low-cost technology. Many biological markers were tested for their ability to serve as 'would-be' stroke biological markers; some of them appear to have a place in the diagnostic work-up of stroke patients. These molecules include Glial Fibrillary Acidic Protein (GFAP), the N-methyl-D-aspartate receptor (NMDA), APO C-III, APO C-I, PARK7, nucleoside diphosphate kinase A (NDKA), S100B, B-type neurotrophic growth factor, von Willebrand factor, matrix metalloproteinase-9, and monocyte chemotactic protein-1. There are obvious limitations to this study, among them the fact that disability does not necessarily correlate with the amount of cerebral tissue lost (the site of stroke may be more important) and the role of the blood-brain barrier in delaying the release of the neuronal proteins in the blood stream. Further studies are awaited to confirm the role of these molecules in the management of acute stroke patients.

  4. Recruitment of Pontin/Reptin by E2f1 amplifies E2f transcriptional response during cancer progression

    PubMed Central

    Tarangelo, Amy; Lo, Nathanael; Teng, Rebecca; Kim, Eunsun; Le, Linh; Watson, Deborah; Furth, Emma E.; Raman, Pichai; Ehmer, Ursula; Viatour, Patrick

    2015-01-01

    Changes in gene expression during tumorigenesis are often considered the consequence of de novo mutations occurring in the tumour. An alternative possibility is that the transcriptional response of oncogenic transcription factors evolves during tumorigenesis. Here we show that aberrant E2f activity, following inactivation of the Rb gene family in a mouse model of liver cancer, initially activates a robust gene expression programme associated with the cell cycle. Slowly accumulating E2f1 progressively recruits a Pontin/Reptin complex to open the chromatin conformation at E2f target genes and amplifies the E2f transcriptional response. This mechanism enhances the E2f-mediated transactivation of cell cycle genes and initiates the activation of low binding affinity E2f target genes that regulate non-cell-cycle functions, such as the Warburg effect. These data indicate that both the physiological and the oncogenic activities of E2f result in distinct transcriptional responses, which could be exploited to target E2f oncogenic activity for therapy. PMID:26639898

  5. Associations among Inflammatory Biomarkers in the Circulating, Plasmatic, Salivary and Intraluminal Anatomical Compartments in Apparently Healthy Preschool Children from the Western Highlands of Guatemala

    PubMed Central

    Soto-Méndez, María José; Romero-Abal, María Eugenia; Aguilera, Concepción María; Rico, María Cruz; Solomons, Noel W.; Schümann, Klaus; Gil, Angel

    2015-01-01

    Background Undernutrition and inflammation are related in many ways; for instance, non-hygienic environments are associated with both poor growth and immunostimulation in children. Objective To describe any existing interaction among different inflammation biomarkers measured in the distinct anatomical compartments of whole blood, feces, plasma and saliva. Methods In this descriptive, cross-sectional study, samples of whole blood, feces, plasma and saliva were collected on the 8th and last week of observation among 87 attendees (42 girls and 45 boys) of 3 daycare centers offering a common 40-day rotating menu in Guatemala’s Western Highlands. Analyses included white blood cell count (WBC), fecal calprotectin, and plasmatic and salivary cytokines including IL-1B, IL-6, IL-8, IL-10 and TNF-α. Associations were assessed using Spearman rank-order and goodness-of-fit correlations, as indicated, followed by backwards-elimination multiple regression analyses to determine predictor variables for IL-10 in both anatomical compartments. Results Of a total of 66 cross-tabulations in the Spearman hemi-matrix, 22 (33%) were significantly associated. All 10 paired associations among the salivary cytokines had a significant r value, whereas 7 of 10 possible associations among plasma cytokines were significant. Associations across anatomical compartments, however, were rarely significant. IL-10 in both biological fluids were higher than corresponding reference values. When a multiple regression model was run in order to determine independent predictors for IL-10 in each anatomical compartment separately, IL-6, IL-8 and TNF-α emerged as predictors in plasma (r2 = 0.514) and IL-1B, IL-8 and TNF-α remained as independent predictors in saliva (r2 = 0.762). Significant cross-interactions were seen with WBC, but not with fecal calprotectin. Conclusion Interactions ranged from robust within the same anatomical compartment to limited to nil across distinct anatomical compartments. The

  6. E2F and its developmental regulation in Xenopus laevis.

    PubMed Central

    Philpott, A; Friend, S H

    1994-01-01

    The transcription factor E2F has been implicated in cell cycle control by virtue of its association with cyclins, cyclin-dependent kinases, and pRb-related tumor suppressor gene products. Eggs and embryos from the frog Xenopus laevis have been used to investigate the characteristics of E2F-like molecules in the Xenopus cell cycle and throughout early development. We find multiple E2F species in Xenopus eggs, at least one of which is modified by phosphorylation. The vast majority of E2F remains in the free form throughout the very early embryonic cell cycle, and it also remains predominantly free until some time after the mid-blastula transition, the onset of zygotic transcription. At this time, E2F complexes significantly to pRb but not to cdk2, although cdk2 binding is found in tissue culture cells from a very advanced stage in embryogenesis. This suggests that the complexing of E2F to cyclins, cyclin-dependent kinases, and tumor suppressor gene products may be controlled separately in early Xenopus development. Thus, the association of E2F with other molecules may not result solely from processes affecting cell cycle progression but may also reflect developmental and differentiation cues. Images PMID:8007993

  7. Nematicidal activity of (E,E)-2,4-decadienal and (E)-2-decenal from Ailanthus altissima against Meloidogyne javanica.

    PubMed

    Caboni, Pierluigi; Ntalli, Nikoletta G; Aissani, Nadhem; Cavoski, Ivana; Angioni, Alberto

    2012-02-01

    Methanol extracts of various plant parts of Ailanthus altissima were tested against the root knot nematode Meloidogyne javanica . Extracts of bark (ABE), wood (AWE), roots (ARE), and leaves (ALE) from A. altissima were investigated against freshly hatched second-stage juveniles (J(2)). AWE was the most active extract, with EC(50/3d) of 58.9 mg/L, while ALE, ARE, and ABE did not show nematicidal activity. The chemical composition of the extracts of A. altissima was determined by gas chromatography-mass spectrometry, and (E,E)-2,4-decadienal, (E)-2-undecenal, (E)-2-decenal, hexanal, nonanal, and furfural were the most prominent constituents. (E,E)-2,4-Decadienal, (E)-2-decenal, and furfural showed the highest nematicidal activity against M. javanica , with EC(50/1d) = 11.7, 20.43, and 21.79 mg/L, respectively, while the other compounds were inactive at the concentrations tested. The results obtained showed that AWE and its constituents (E,E)-2,4-decadienal and (E)-2-decenal could be considered as potent botanical nematicidal agents.

  8. Random phage mimotopes recognized by monoclonal antibodies against the pyruvate dehydrogenase complex-E2 (PDC-E2).

    PubMed

    Cha, S; Leung, P S; Van de Water, J; Tsuneyama, K; Joplin, R E; Ansari, A A; Nakanuma, Y; Schatz, P J; Cwirla, S; Fabris, L E; Neuberger, J M; Gershwin, M E; Coppel, R L

    1996-10-01

    Dihydrolipoamide acetyltransferase, the E2 component of the pyruvate dehydrogenase complex (PDC-E2), is the autoantigen most commonly recognized by autoantibodies in primary biliary cirrhosis (PBC). We identified a peptide mimotope(s) of PDC-E2 by screening a phage-epitope library expressing random dodecapeptides in the pIII coat protein of fd phage using C355.1, a murine monoclonal antibody (mAb) that recognizes a conformation-dependent epitope in the inner lipoyl domain of PDC-E2 and uniquely stains the apical region of bile duct epithelium (BDE) only in patients with PBC. Eight different sequences were identified in 36 phage clones. WMSYPDRTLRTS was present in 29 clones; WESYPFRVGTSL, APKTYVSVSGMV, LTYVSLQGRQGH, LDYVPLKHRHRH, AALWGVKVRHVS, KVLNRIMAGVRH and GNVALVSSRVNA were singly represented. Three common amino acid motifs (W-SYP, TYVS, and VRH) were shared among all peptide sequences. Competitive inhibition of the immunohistochemical staining of PBC BDE was performed by incubating the peptides WMSYPDRTLRTS, WESYPDRTLRTS, APKTYVSVSGMV, and AALWGVKVRHVS with either C355.1 or a second PDC-E2-specific mAb, C150.1. Both mAbs were originally generated to PDC-E2 but map to distinct regions of PDC-E2. Two of the peptides, although selected by reaction with C355.1, strongly inhibited the staining of BDE by C150.1, whereas the peptide APKTYVSVSGMV consistently inhibited the staining of C355.1 on biliary duct epithelium more strongly than the typical mitochondrial staining of hepatocytes. Rabbit sera raised against the peptide WMSYPDRTLRTS stained BDE of livers and isolated bile duct epithelial cells of PBC patients more intensively than controls. The rabbit sera stained all size ducts in normals, but only small/medium-sized ductules in PBC livers. These studies provide evidence that the antigen present in BDE is a molecular mimic of PDC-E2, and not PDC-E2 itself.

  9. A MUB E2 structure reveals E1 selectivity between cognate ubiquitin E2s in eukaryotes

    PubMed Central

    Lu, Xiaolong; Malley, Konstantin R.; Brenner, Caitlin C.; Koroleva, Olga; Korolev, Sergey; Downes, Brian P.

    2016-01-01

    Ubiquitin (Ub) is a protein modifier that controls processes ranging from protein degradation to endocytosis, but early-acting regulators of the three-enzyme ubiquitylation cascade are unknown. Here we report that the prenylated membrane-anchored ubiquitin-fold protein (MUB) is an early-acting regulator of subfamily-specific E2 activation. An AtMUB3:AtUBC8 co-crystal structure defines how MUBs inhibit E2∼Ub formation using a combination of E2 backside binding and a MUB-unique lap-bar loop to block E1 access. Since MUBs tether Arabidopsis group VI E2 enzymes (related to HsUbe2D and ScUbc4/5) to the plasma membrane, and inhibit E2 activation at physiological concentrations, they should function as potent plasma membrane localized regulators of Ub chain synthesis in eukaryotes. Our findings define a biochemical function for MUB, a family of highly conserved Ub-fold proteins, and provide an example of selective activation between cognate Ub E2s, previously thought to be constitutively activated by E1s. PMID:27550514

  10. A MUB E2 structure reveals E1 selectivity between cognate ubiquitin E2s in eukaryotes

    NASA Astrophysics Data System (ADS)

    Lu, Xiaolong; Malley, Konstantin R.; Brenner, Caitlin C.; Koroleva, Olga; Korolev, Sergey; Downes, Brian P.

    2016-08-01

    Ubiquitin (Ub) is a protein modifier that controls processes ranging from protein degradation to endocytosis, but early-acting regulators of the three-enzyme ubiquitylation cascade are unknown. Here we report that the prenylated membrane-anchored ubiquitin-fold protein (MUB) is an early-acting regulator of subfamily-specific E2 activation. An AtMUB3:AtUBC8 co-crystal structure defines how MUBs inhibit E2~Ub formation using a combination of E2 backside binding and a MUB-unique lap-bar loop to block E1 access. Since MUBs tether Arabidopsis group VI E2 enzymes (related to HsUbe2D and ScUbc4/5) to the plasma membrane, and inhibit E2 activation at physiological concentrations, they should function as potent plasma membrane localized regulators of Ub chain synthesis in eukaryotes. Our findings define a biochemical function for MUB, a family of highly conserved Ub-fold proteins, and provide an example of selective activation between cognate Ub E2s, previously thought to be constitutively activated by E1s.

  11. Vitellogenin in black turtle (Chelonia mydas agassizii): purification, partial characterization, and validation of an enzyme-linked immunosorbent assay for its detection.

    PubMed

    Sifuentes-Romero, Itzel; Vázquez-Boucard, Celia; Sierra-Beltrán, Arturo P; Gardner, Susan C

    2006-02-01

    Black turtle plasmatic vitellogenin (VTG) was purified from 17beta-estradiol-induced males using ion-exchange chromatography. The isolated protein was identified as VTG by its glycolipoprotein nature and amino acid sequence homology with other vertebrate VTG. It was characterized as a 500-kDa dimer composed of two identical, 200- to 240-kDa monomers. Polyclonal antibodies raised against black turtle VTG showed high titer and specificity, as demonstrated by enzyme-linked immunosorbent assay and Western blot analysis, respectively. The range of the assay was estimated to be between 15 ng/ml and 2 microg/ml, and the inter- and intra-assay coefficients of variation were 9.4 and 7.3%, respectively. Black turtle antibody cross-reacted with VTG of two other sea turtle species, Caretta caretta (loggerhead) and Eretmochelys imbricata (hawksbill), extending the applicability of the assay as part of a sea turtle health assessment program.

  12. Influence of progesterone and 17 alpha hydroxyprogesterone upon the BANA-hydrolytic activity of human sperm.

    PubMed

    Valencia-Sánchez, A; Mercado-Pichardo, E

    1991-01-01

    Our knowledge about temporal relationships between reproductive processes and defined changes in the plasmatic concentrations of 17 beta-estradiol, Follicle-stimulating hormone (FSH), Luteinizing hormone (LH) and progesterone (P) is still incomplete. Is known that in periovulatory phase the chance of fertilization increases to its maximum. The results obtained using different concentration of P have shown that at high concentration a fast liberation or/and exposure of the BANA-hydrolytic (B-H) activity is present. However, with low concentrations of P the enzymatic activity keeps a relation with the exposure time. In similar experimental conditions and using 17 alpha-hydroxyprogesterone it has been no change in the B-H activity. The results obtained in the present study suggest that the P possibly acts upon the sperm stimulating its hydrolytic activity, allowing its penetration through the zona pellucida of the ovum.

  13. Structure and estrogenic activity of new lignans from Iryanthera lancifolia.

    PubMed

    Mesa-Siverio, Dulce; Machín, Rubén P; Estévez-Braun, Ana; Ravelo, Angel G; Lock, Olga

    2008-03-15

    Five new dibenzylbutane type lignans (1-5) were isolated from the stem bark of Iryanthera lancifolia. Their structures were determined by extensive 1D and 2D NMR spectroscopic studies and chemical evidence. Seventeen of the isolated compounds were tested for their estrogenic activities in the estrogen responsive human breast cancer cell line MCF-7 BUS using the E-Screen proliferation assay. Cell proliferation was evaluated by the SRB assay to calculate the estrogenic parameters. The majority of the compounds induced a mitogenic response. This effect, given as Relative Proliferative Effect (RPE) to reference estrogen 17beta-estradiol (E(2)), ranged between 14% and 84%.

  14. Circannual rhythm of plasmatic vitamin D levels and the association with markers of psychophysical stress in a cohort of Italian professional soccer players.

    PubMed

    Lombardi, Giovanni; Vitale, Jacopo Antonino; Logoluso, Sergio; Logoluso, Giovanni; Cocco, Nino; Cocco, Giulio; Cocco, Antonino; Banfi, Giuseppe

    2017-01-01

    Adequate plasmatic Vitamin D levels are crucial to maintain calcium homeostasis and bone metabolism both in the general population and in athletes. Correct dietary supply and a regular sun exposure are fundamental for allowing the desired and effective fitness level. Past studies highlighted a scenario of Vitamin D insufficiency among professional soccer players in several countries, especially in North Europe, whilst a real deficiency in athletes is rare. The typical seasonal fluctuations of Vitamin D are wrongly described transversally in athletes belonging to teams that play at different latitudes and a chronobiologic approach studying the Vitamin D circannual rhythm in soccer players has not been described yet. Therefore, we studied plasma vitamin D, cortisol, testosterone, and creatin kinase (CK) concentrations in three different Italian professional teams training at the same latitude during a period of two consecutive competitive seasons (2013 and 2014). In this retrospective observational study, 167 professional soccer players were recruited (mean age at sampling 25.1 ± 4.7 years) and a total of 667 blood drawings were carried out to determine plasma 25(OH)D, serum cortisol, serum testosterone and CK levels. Testosterone to cortisol ratio (TC) was calculated based as a surrogate marker of overtraining and psychophysical stress and each athlete was drawn until a maximum of 5 times per season. Data extracted by a subgroup of players that underwent at least 4 sample drawings along a year (N = 45) were processed with the single and population mean cosinor tests to evaluate the presence of circannual rhythms: the amplitude (A), acrophase (Φ) and the MESOR (M) are described. In total, 55 players (32.9%) had an insufficient level of 25(OH)D during the seasons and other 15 athletes (9.0%) showed, at least once, a deficiency status of Vitamin D. The rhythmometric analyses applied to the data of Vitamin D revealed the presence of a significant circannual rhythm (p

  15. 8 Be Anomalous Internal Pair Production: Possible E2 Transitions

    NASA Astrophysics Data System (ADS)

    Ward, Thomas; Koltick, David; Wang, Haoyu

    2017-01-01

    Significant enhancement of 8 Be internal pair production at 16.7 MeV with large angle correlations from the 18.150 MeV (Jπ =1+) level have been interpreted as a possible dark matter candidate, a light (Jπ =1+) neutral boson or a fifth-force vector gauge boson. We present a conventional alternative interpretation, unseen E2 transitions from the Jπ =2+ levels at 16.626 MeV and 16.922 MeV populated in the decay of the 18.150 MeV (Jπ =1+) level. The calculated E2 transition probabilities agree well with the measured pair production intensity in the back angle correlation where one expects the E2 gamma-ray correlation to peak. Work partially funded under auspices of USDOE-NE Contract DE-DT0004091.

  16. Revisiting Grodzins systematics of B(E2) values

    DOE PAGES

    Pritychenko, B.; Birch, M.; Singh, B.

    2017-04-03

    Using Grodzins formalism, we analyze systematics of our latest evaluated B(E2) data for all the even–even nuclei in Z=2–104. The analysis indicates a low predictive power of systematics for a large number of cases, and a strong correlation between B(E2) fit values and nuclear structure effects. These findings provide a strong rationale for introduction of individual or elemental (grouped by Z) fit parameters. The current estimates of quadrupole collectivities for systematics of even–even nuclei yield complementary values for comparison with experimental results and theoretical calculations. Furthermore, the lists of fit parameters and predicted B(E2) values are given and possible implicationsmore » are discussed.« less

  17. Hepatitis C Virus E2 Envelope Glycoprotein Core Structure

    SciTech Connect

    Kong, Leopold; Giang, Erick; Nieusma, Travis; Kadam, Rameshwar U.; Cogburn, Kristin E.; Hua, Yuanzi; Dai, Xiaoping; Stanfield, Robyn L.; Burton, Dennis R.; Ward, Andrew B.; Wilson, Ian A.; Law, Mansun

    2014-08-26

    Hepatitis C virus (HCV), a Hepacivirus, is a major cause of viral hepatitis, liver cirrhosis, and hepatocellular carcinoma. HCV envelope glycoproteins E1 and E2 mediate fusion and entry into host cells and are the primary targets of the humoral immune response. The crystal structure of the E2 core bound to broadly neutralizing antibody AR3C at 2.65 angstroms reveals a compact architecture composed of a central immunoglobulin-fold β sandwich flanked by two additional protein layers. The CD81 receptor binding site was identified by electron microscopy and site-directed mutagenesis and overlaps with the AR3C epitope. The x-ray and electron microscopy E2 structures differ markedly from predictions of an extended, three-domain, class II fusion protein fold and therefore provide valuable information for HCV drug and vaccine design.

  18. Revisiting Grodzins systematics of B(E2) values

    NASA Astrophysics Data System (ADS)

    Pritychenko, B.; Birch, M.; Singh, B.

    2017-06-01

    Using Grodzins formalism as modified by S. Raman et al. (1988) [7] and D. Habs et al. (2002) [14], we analyze systematics of our latest evaluated B(E2) data for all the even-even nuclei in Z = 2- 104 range published in At. Data Nucl. Data Tables 107 (2016) 1 [5]. The analysis indicates a low predictive power of systematics for a large number of cases, and a strong correlation between B(E2) fit values and nuclear structure effects. These findings provide a strong rationale for introduction of individual or elemental (grouped by Z) fit parameters. The current estimates of quadrupole collectivities for systematics of even-even nuclei yield complementary values for comparison with experimental results and theoretical calculations. The lists of fit parameters and predicted B(E2) values are given and possible implications are discussed.

  19. Extra-amniotic prostaglandin E2 and the unfavourable cervix.

    PubMed

    Shepherd, J; Sims, C; Craft, I

    1976-10-02

    A small dose of prostaglandin E2 suspended in a viscous medium was instilled as a single application into the extra-amniotic space of patients with unfavourable induction features the day before planned induction in an attempt to improve the condition of the cervix. Two groups of 15 patients were studied, one receiving prostaglandin E2 250 mug suspended in methyl ethyl cellulose ('Tylose') 6% solution, and the other tylose alone. Cervical status did not change in those receiving tylose alone, whereas a significant improvement occurred in 14 out of 15 patients receiving the prostaglandin. Labour began before formal induction in 1 patient receiving tylose and in 8 receiving prostaglandin.

  20. Random phage mimotopes recognized by monoclonal antibodies against the pyruvate dehydrogenase complex-E2 (PDC-E2).

    PubMed Central

    Cha, S; Leung, P S; Van de Water, J; Tsuneyama, K; Joplin, R E; Ansari, A A; Nakanuma, Y; Schatz, P J; Cwirla, S; Fabris, L E; Neuberger, J M; Gershwin, M E; Coppel, R L

    1996-01-01

    Dihydrolipoamide acetyltransferase, the E2 component of the pyruvate dehydrogenase complex (PDC-E2), is the autoantigen most commonly recognized by autoantibodies in primary biliary cirrhosis (PBC). We identified a peptide mimotope(s) of PDC-E2 by screening a phage-epitope library expressing random dodecapeptides in the pIII coat protein of fd phage using C355.1, a murine monoclonal antibody (mAb) that recognizes a conformation-dependent epitope in the inner lipoyl domain of PDC-E2 and uniquely stains the apical region of bile duct epithelium (BDE) only in patients with PBC. Eight different sequences were identified in 36 phage clones. WMSYPDRTLRTS was present in 29 clones; WESYPFRVGTSL, APKTYVSVSGMV, LTYVSLQGRQGH, LDYVPLKHRHRH, AALWGVKVRHVS, KVLNRIMAGVRH and GNVALVSSRVNA were singly represented. Three common amino acid motifs (W-SYP, TYVS, and VRH) were shared among all peptide sequences. Competitive inhibition of the immunohistochemical staining of PBC BDE was performed by incubating the peptides WMSYPDRTLRTS, WESYPDRTLRTS, APKTYVSVSGMV, and AALWGVKVRHVS with either C355.1 or a second PDC-E2-specific mAb, C150.1. Both mAbs were originally generated to PDC-E2 but map to distinct regions of PDC-E2. Two of the peptides, although selected by reaction with C355.1, strongly inhibited the staining of BDE by C150.1, whereas the peptide APKTYVSVSGMV consistently inhibited the staining of C355.1 on biliary duct epithelium more strongly than the typical mitochondrial staining of hepatocytes. Rabbit sera raised against the peptide WMSYPDRTLRTS stained BDE of livers and isolated bile duct epithelial cells of PBC patients more intensively than controls. The rabbit sera stained all size ducts in normals, but only small/medium-sized ductules in PBC livers. These studies provide evidence that the antigen present in BDE is a molecular mimic of PDC-E2, and not PDC-E2 itself. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8855289

  1. E2F4 Function in G2

    PubMed Central

    Plesca, Dragos; Crosby, Meredith E.; Gupta, Damodar; Almasan, Alexandru

    2008-01-01

    Mammalian cells undergo cell cycle arrest in response to DNA damage through multiple checkpoint mechanisms. One such checkpoint pathway maintains genomic integrity by delaying mitotic progression in response to genotoxic stress. Transition though the G2 phase and entry into mitosis is considered to be regulated primarily by cyclin B1 and its associated catalytically active partner Cdk1. While not necessary for its initiation, the p130 and Rb-dependent target genes have emerged as being important for stable maintenance of a G2 arrest. It was recently demonstrated that by interacting with p130, E2F4 is present in the nuclei and plays a key role in the maintenance of this stable G2 arrest. Increased E2F4 levels and its translocation to the nucleus following genotoxic stress result in downregulation of many mitotic genes and as a result promote a G0-like state. Irradiation of E2F4-depleted cells leads to enhanced cellular DNA double-strand breaks that may be measured by comet assays. It also results in cell death that is characterized by caspase activation, sub-G1 and sub-G2 DNA content, and decreased clonogenic cell survival. Here we review these recent findings and discuss the mechanisms of G2 phase checkpoint activation and maintenance with a particular focus on E2F4. PMID:17507799

  2. E-2C Loads Calibration in DFRC Flight Loads Lab

    NASA Technical Reports Server (NTRS)

    Schuster, Lawrence S.

    2008-01-01

    Objectives: a) Safely and efficiently perform structural load tests on NAVAIR E-2C aircraft to calibrate strain gage instrumentation installed by NAVAIR; b) Collect load test data and derive loads equations for use in NAVAIR flight tests; and c) Assist flight test team with use of loads equations measurements at PAX River.

  3. 26 CFR 31.3231(e)-2 - Contribution base.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 15 2011-04-01 2011-04-01 false Contribution base. 31.3231(e)-2 Section 31.3231... Contribution base. The term compensation does not include any remuneration paid during any calendar year by an employer to an employee for services rendered in excess of the applicable contribution base. For...

  4. 26 CFR 31.3231(e)-2 - Contribution base.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 15 2013-04-01 2013-04-01 false Contribution base. 31.3231(e)-2 Section 31.3231... Contribution base. The term compensation does not include any remuneration paid during any calendar year by an employer to an employee for services rendered in excess of the applicable contribution base. For...

  5. 26 CFR 31.3231(e)-2 - Contribution base.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 15 2010-04-01 2010-04-01 false Contribution base. 31.3231(e)-2 Section 31.3231... Contribution base. The term compensation does not include any remuneration paid during any calendar year by an employer to an employee for services rendered in excess of the applicable contribution base. For...

  6. 26 CFR 31.3231(e)-2 - Contribution base.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 15 2014-04-01 2014-04-01 false Contribution base. 31.3231(e)-2 Section 31.3231... Contribution base. The term compensation does not include any remuneration paid during any calendar year by an employer to an employee for services rendered in excess of the applicable contribution base. For...

  7. 26 CFR 31.3231(e)-2 - Contribution base.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 15 2012-04-01 2012-04-01 false Contribution base. 31.3231(e)-2 Section 31.3231... Contribution base. The term compensation does not include any remuneration paid during any calendar year by an employer to an employee for services rendered in excess of the applicable contribution base. For...

  8. Plasma prostaglandin E(2) metabolite levels during labor induction with a sustained-release prostaglandin E(2) vaginal insert.

    PubMed

    Goharkhay, N; Stanczyk, F Z; Gentzschein, E; Wing, D A

    2000-01-01

    To measure prostaglandin E(2) levels during labor induction with a sustained-release vaginal polymer insert (prostaglandin E(2) insert) and to determine whether Bishop score change correlated with tachysystole. Twelve primiparas and 12 multiparas were treated with a 0.3 mg per hour sustained-release polymer vaginal prostaglandin E(2) insert for up to 24 hours. Bishop score was assessed at start and end of therapy, and serum samples were collected at 4-hour intervals. Prostaglandin E(2) metabolite (PGEM) levels were measured by specific enzyme immunoassay. Exposure averaged 13.5 +/- 7.2 hours. Four patients (16.7%, three nulliparas) had tachysystole. Mean PGEM levels increased from 187 +/- 42 pg/mL at baseline to 548 +/- 110 pg/mL at 12 hours (P <.05) and remained relatively stable thereafter. Nulliparas with Bishop score changes of four points or more had the highest increase, with average peak levels of 985 +/- 109 pg/mL, compared with 452 +/- 58 pg/mL for all others (P <.001). Patients with tachysystole had higher 4-hour (P <.01) and overall (P <.04) increases in PGEM level. Removal of the insert led to an average decrease of 335 pg/mL in PGEM levels (P <.01). The decrease correlated with the PGEM level measured before removal (r =.94, P <.0001) and the maximum PGEM increase from baseline (r =.94, P <.0001). The mean mixed venous cord PGEM level was 409 +/- 375 pg/mL. Administration of the prostaglandin E(2) insert led to a sustained increase in circulating PGEM levels in women who had labor induction. Peak PGEM levels correlated with Bishop score improvement. Rapid increases in prostaglandin E(2) levels might cause tachysystole.

  9. Measurement of estrogenic activity in sediments from Haihe and Dagu River, China.

    PubMed

    Song, Maoyong; Xu, Yan; Jiang, Qinting; Lam, Paul K S; O'Toole, Desmond K; Giesy, John P; Jiang, Guibin

    2006-07-01

    Sediments from two rivers in China, the Haihe and Dagu Rivers, were examined for estrogenic activity using an estrogen receptor (ER)-mediated in vitro bioassay system. ER-active compounds were isolated from sediments by Soxhlet extraction, and the crude extracts were fractionated using a florisil column into three fractions. The estrogenic activity of each extract was detected by measuring luciferase activity in the human breast cancer cell line MCF-7 transfected with a luciferase receptor gene. Significant estrogenic activity was observed in each total extract. The 17beta-estradiol equivalents (E2-EQs) ranged from 8.24 to 95.28 ng E2 g(-1) dw. As a result, the relative estrogenic potencies of three fractions in this study descended in the order of Fraction 3>Fraction 2>Fraction 1. The results of the bioassay analysis indicated the heavy pollution status of these sites with estrogenic contaminants. In this study, five selected chemicals, the natural estrogens 17beta-estradiol (E2) and estrone (E1), and the xeno-estrogens 4-octylphenol (OP), 4-nonylphenol (NP), and Bisphenol A (BPA) were also analyzed using the in vitro bioassay. The estrogenic activity of these chemicals were E2>E1>NP>OP>BPA.

  10. [New method for the determination of estrogen and progesterone receptors in human breast cell lines].

    PubMed

    Olea, N; Devleeschower, N; Leclercq, G

    1985-12-01

    A method for the determination of estrogen and progesterone receptor levels in human mammary cell lines (MCF-7, Cama-1, ZR-75-1, Evsa-T and HBL-100) is described. Cells cultured as monolayers were incubated with the tritiated steroids, [3H]-17 beta-Estradiol or [3H] ORG-2058. Binding of steroids to receptors was a function of cellular uptake. Incubation periods of 50 min were sufficient to attain maximum intracellular incorporation. The binding of 17 beta-E2 and ORG-2058 to MCF-7 cells, a phenomenon which is saturable at low concentrations for the radioactive ligand, is a linear function of the number of cells assayed (Interval: 2.5 X 10(4) to 1.5 X 10(6) cells per well). Binding data and their Scatchard plot allowed for the calculation of affinity and capacity values. Thus, for ER, Kd = 2.0 +/- 0.5 X 10(-10) M and n = 3.76 +/- 0.91 Fmol/microgram DNA, and for PgR Kd = 2.0 +/- 0.2 X 10(-10) M and n = 14.02 +/- 2.30 Fmol/microgram DNA (Mean +/- SD). Binding specificity of 17 beta-Estradiol and ORG-2058 to MCF-7 cells was analysed by means of study on the inhibitory effect of increasing concentrations of unlabelled competitors: 17 beta-Estradiol, ORG-2058, Estrone, DES, R-5020, Cortisol, Androsterone and Testosterone. Only pharmacological doses of some of the mentioned molecules produce displacement of the hormonereceptor binding. This phenomenon appears to be related to the affinity of these chemical compounds for the receptor macromolecules to which estrogens and progesterone bind.

  11. Synergistic functions of E2F7 and E2F8 are critical to suppress stress-induced skin cancer

    PubMed Central

    Thurlings, I; Martínez-López, L M; Westendorp, B; Zijp, M; Kuiper, R; Tooten, P; Kent, L N; Leone, G; Vos, H J; Burgering, B; de Bruin, A

    2017-01-01

    E2F transcription factors are important regulators of the cell cycle, and unrestrained activation of E2F-dependent transcription is considered to be an important driver of tumor formation and progression. Although highly expressed in normal skin and skin cancer, the role of the atypical E2Fs, E2F7 and E2F8, in keratinocyte homeostasis, regeneration and tumorigenesis is unknown. Surprisingly, keratinocyte-specific deletion of E2F7 and E2F8 in mice did not interfere with skin development and wound healing. However, the rate for successful isolation and establishment of E2f7/8-deficient primary keratinocyte cultures was much higher than for wild-type keratinocytes. Moreover, E2f7/8-deficient primary keratinocytes proliferate more efficiently under stress conditions, such as low/high confluence or DNA damage. Application of in vivo stress using the DMBA/TPA skin carcinogenesis protocol revealed that combined inactivation of E2f7/8 enhanced tumorigenesis and accelerated malignant progression. Loss of atypical E2Fs resulted in increased expression of E2F target genes, including E2f1. Additional loss of E2f1 did not rescue, but worsened skin tumorigenesis. We show that loss of E2F7/8 triggers apoptosis via induction of E2F1 in response to stress, indicating that the tumor-promoting effect of E2F7/8 inactivation can be partially compensated via E2F1-dependent apoptosis. Importantly, E2F7/8 repressed a large set of E2F target genes that are highly expressed in human patients with skin cancer. Together, our studies demonstrate that atypical E2Fs act as tumor suppressors, most likely via transcriptional repression of cell cycle genes in response to stress. PMID:27452520

  12. [Prostaglandin E2 gel for labor induction in preterm pregnancy].

    PubMed

    Sieńko, Jacek; Czajkowski, Krzysztof; Nowak, Rafał; Broś, Magdalena; Kunicki, Michał; Strzyzewski, Wojciech

    2003-01-01

    Endocervical prostaglandin E2 gel administration is widely accepted mean of induction of labor in pregnancy at term. Further investigation is needed to assess its usage in pregnancy below 37 weeks' gestation. The aim of this study is to analyse the course of labor, its complications and neonatal outcome in preterm deliveries induced with endocervical dinoprostone. We conducted a retrospective study of 22 preterm deliveries induced with dinoprostone. A control group consisted of 26 pregnancies at term. The incidence of cesarean sections was comparable in both preterm and term deliveries (45 vs. 41%, p = 0.38). We found no differences in characteristics of indications of operative delivery, duration of particular stages of labor; time from dinoprostone administration to the beginning of 1st stage of labor, estimated blood loss. 1 and 5-minute Apgar scores were similar in both groups. Endocervical prostaglandin E2 gel administration seems to be a safe method of induction of labor in preterm pregnancy.

  13. Chang'e-2 spacecraft observations of asteroid 4179 Toutatis

    NASA Astrophysics Data System (ADS)

    Ji, Jianghui; Jiang, Yun; Zhao, Yuhui; Wang, Su; Yu, Liangliang

    2016-01-01

    On 13 December 2012, Chang'e-2 completed a successful flyby of the near-Earth asteroid 4179 Toutatis at a closest distance of 770 meters from the asteroid's surface. The observations show that Toutatis has an irregular surface and its shape resembles a ginger-root of a smaller lobe (head) and a larger lobe (body). Such bilobate shape is indicative of a contact binary origin for Toutatis. In addition, the high-resolution images better than 3 meters provide a number of new discoveries about this asteroid, such as an 800-meter depression at the end of the large lobe, a sharply perpendicular silhouette near the neck region, boulders, indicating that Toutatis is probably a rubble-pile asteroid. Chang'e-2 observations have significantly revealed new insights into the geological features and the formation and evolution of this asteroid. In final, we brief the future Chinese asteroid mission concept.

  14. Generalized seniority and E 2 transitions in the tin isotopes

    NASA Astrophysics Data System (ADS)

    Morales, Irving O.; Van Isacker, P.; Talmi, I.

    2011-09-01

    Recently, a shallow minimum was discovered in B(E2) values in even Sn isotopes around the middle of the neutron major shell. A peak in that region was expected according to calculations using generalized seniority. In a model calculation we show that the observed shape is consistent with generalized seniority. It seems to be due to the order of filling of j-orbits.

  15. Prostaglandin E2 Regulation of Chondrocyte Proliferation and Differentiation

    DTIC Science & Technology

    1994-05-01

    increases bone prostaglandin E. Effect of acetylsalicylic acid on disuse osteoporosis studied in dogs. Acta Orthopaedica Scandinavica, 62:238-243. 121...bovine serum, 1% antibiotics, and 50 pg/ml ascorbic acid in 100% humidity at 37oC. Prostaglandin E2 was added to confluent, fourth passage cultures... acid from membrane phospholipids. This, in turn, may lead to the formation of prostaglandins, thromboxanes and prostacyclins through the metabolism of

  16. Advanced Stirling Convertor (ASC-E2) Characterization Testing

    NASA Technical Reports Server (NTRS)

    Williams, Zachary D.; Oriti, Salvatore M.

    2012-01-01

    Testing has been conducted on Advanced Stirling Convertor (ASC-E2) convertors at NASA Glenn Research Center in support of the Advanced Stirling Radioisotope Generator (ASRG) Project. This testing has been conducted to understand sensitivities of convertor parameters due to environmental and operational changes during operation of the ASRG in missions to space. This paper summarizes test results and explains in terms of operation of the ASRG during space missions.

  17. Advanced Stirling Convertor (ASC-E2) Characterization Testing

    NASA Technical Reports Server (NTRS)

    Williams, Zachary D.; Oriti, Salvatore M.

    2012-01-01

    Testing has been conducted on Advanced Stirling Convertors (ASCs)-E2 at NASA Glenn Research Center in support of the Advanced Stirling Radioisotope Generator (ASRG) project. This testing has been conducted to understand sensitivities of convertor parameters due to environmental and operational changes during operation of the ASRG in missions to space. This paper summarizes test results and explains the operation of the ASRG during space missions

  18. Transcription factors E2F1 and E2F3 are expressed in placenta but do not regulate MMP14.

    PubMed

    Kaitu'u-Lino, T J; Hastie, R; Cannon, P; Nguyen, H; Lee, S; Hannan, N J; Tong, S

    2015-08-01

    Preeclampsia is a serious complication of pregnancy for which there are no efficacious medical treatments. Soluble endoglin is as an anti-angiogenic factor that contributes to the pathogenesis of the disease, however little is known about its molecular regulation in placenta. Recent data has demonstrated E2F transcription factors directly regulate MMPs in metastatic disease. Of particular interest was the capacity of E2F1 and E2F3 to up-regulate MMP14, a protease that cleaves and releases soluble endoglin from placenta. The aim of this study was to characterize E2F1 and E2F3 in preeclamptic placenta and assess whether silencing affects soluble endoglin release. E2F1 and E2F3 mRNA, protein expression and localization were assessed in severe early onset preeclamptic and preterm control placentas (delivered <34 weeks gestation). E2F siRNA was administered to primary trophoblast and primary endothelial cells and effect on MMP14 mRNA expression and soluble endoglin secretion assessed. E2F1 and E2F3 were localized to the syncytiotrophoblast. E2F1 was significantly down regulated in severe preeclamptic placentas, while E2F3 was unchanged. Silencing E2F1 did not decrease MMP14 expression in primary trophoblast or endothelial cells. However, E2F1 silencing resulted in a significant increase in soluble endoglin secretion from both cell types, and silencing of E2F3 also significantly increased soluble endoglin release from primary trophoblast. This study demonstrates that E2F1 and E2F3 are present within the syncytiotrophoblast of placenta and that E2F1 is reduced in preeclampsia. Although silencing of either E2F1 or E2F3 does not alter MMP14 expression, both appear to regulate soluble endoglin release. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Poster 14: Explorer of Enceladus and Titan (E2T)

    NASA Astrophysics Data System (ADS)

    Mitri, Giuseppe; Tobie, Gabriel; Postberg, Frank; Soderblom, Jason M.; Wurz, Peter; Barnes, Jason W.; Berga, Marco; Coustenis, Athena; D'Ottavio, Andrea Hayes, Alexander G.; Hayne, Paul O.; Lebreton, Jean-Pierre; Lorenz, Ralph D.; Martelli, Andrea; Petropoulos, Anastassios E.; Yen, Chen-wan L.; Reh, Kim R.; Sotin, Christophe; Srama, Ralf; Tortora, Paolo

    2016-06-01

    The NASA-ESA Cassini-Huygens mission has revealed Titan and Enceladus to be two of the most enigmatic worlds in the Solar System. Titan, with its organically rich and dynamic atmosphere and geology, and Enceladus, with its active plume, both harboring subsurface oceans, are prime environments in which to investigate the conditions for the emergence of life and the habitability of Ocean Worlds. Explorer of Enceladus and Titan (E2T) is dedicated to investigating the evolution and habitability of these Saturnian satellites and will be proposed as a medium-class mission led by ESA in collaboration with NASA in response to ESA's M5 Call. E2T has a focused payload that will provide in-situ sampling and high-resolution imaging during multiple flybys of Enceladus and Titan using a solar-electric powered spacecraft in orbit around Saturn. The E2T mission will provide high-resolution mass spectroscopy of the plume emanating from Enceladus' south polar terrain (SPT) and of Titan's upper atmosphere as well as high-resolution IR imaging of the plume and the source fractures on Enceladus' SPT, and it will detail Titan's geomorphology at 50-100 m resolution. The E2T mission has three scientific goals: 1) Investigate the origin and evolution of volatile-rich icy worlds by examining both Enceladus and Titan, 2) Investigate the habitability and potential for life in ocean worlds on both Enceladus and Titan and 3) Investigate Titan as an Earth-like world with an evolving climate and landscape. These investigations will be accomplished by measuring the nature, abundance and isotopic properties of solid- and vapor-phase species in Enceladus' plume and Titan's upper atmosphere. E2T's high-resolution time-of-flight mass spectrometers will enable us to untangle the ambiguities left by Cassini regarding the identification of low-mass organic species, identify high-mass organic species for the first time, further constrain trace species such as the noble gases, and clarify the evolution of

  20. Crystal structure and magnetic modulation in β -C e2O2FeS e2

    NASA Astrophysics Data System (ADS)

    Wang, Chun-Hai; Ainsworth, C. M.; Champion, S. D.; Stewart, G. A.; Worsdale, M. C.; Lancaster, T.; Blundell, S. J.; Brand, Helen E. A.; Evans, John S. O.

    2017-08-01

    We report a combination of x-ray and neutron diffraction studies, Mössbauer spectroscopy, and muon spin relaxation (μ+SR ) measurements to probe the structure and magnetic properties of the semiconducting β -C e2O2FeS e2 oxychalcogenide. We report a structural description in space group P n a 21 which is consistent with diffraction data and second harmonic generation measurements and reveal an order-disorder transition on one Fe site at TOD≈330 K . Susceptibility measurements, Mössbauer, and μ+SR reveal antiferromagnetic ordering below TN=86 K and more complex short range order above this temperature. 12 K neutron diffraction data reveal a modulated magnetic structure with q =0.444 bN* .

  1. An E2 Accessory Domain Increases Affinity for the Anaphase-promoting Complex and Ensures E2 Competition*

    PubMed Central

    Girard, Juliet R.; Tenthorey, Jeanette L.; Morgan, David O.

    2015-01-01

    The anaphase-promoting complex/cyclosome (APC/C) is a member of the RING family of E3 ubiquitin ligases, which promote ubiquitin transfer from an E2 ubiquitin-conjugating enzyme to a substrate. In budding yeast, the APC/C collaborates with two E2s, Ubc4 and Ubc1, to promote the initiation and elongation, respectively, of polyubiquitin chains on the substrate. Ubc4 and Ubc1 are thought to compete for the same site on the APC/C, but it is not clear how their affinities are balanced. Here, we demonstrate that a C-terminal ubiquitin-associated (UBA) domain enhances the affinity of Ubc1 for the APC/C. Deletion of the UBA domain reduced apparent APC/C affinity for Ubc1 and decreased polyubiquitin chain length. Surprisingly, the positive effect of the UBA domain was not due to an interaction with the acceptor ubiquitin attached to the APC/C substrate or the donor ubiquitin attached to Ubc1 itself. Instead, our evidence suggests that the UBA domain binds to a site on the APC/C core, thereby increasing Ubc1 affinity and enhancing its ability to compete with Ubc4. The UBA domain is required for normal Ubc1 function and E2 competition in vivo. Thus, the UBA domain of Ubc1 ensures efficient polyubiquitination of substrate by balancing Ubc1 affinity with that of Ubc4. PMID:26306044

  2. The ancient function of RB-E2F pathway: insights from its evolutionary history.

    PubMed

    Cao, Lihuan; Peng, Bo; Yao, Lei; Zhang, Xinming; Sun, Kuan; Yang, Xianmei; Yu, Long

    2010-09-20

    The RB-E2F pathway is conserved in most eukaryotic lineages, including animals and plants. E2F and RB family proteins perform crucial functions in cycle controlling, differentiation, development and apoptosis. However, there are two kinds of E2Fs (repressive E2Fs and active E2Fs) and three RB family members in human. Till now, the detail evolutionary history of these protein families and how RB-E2F pathway evolved in different organisms remain poorly explored. We performed a comprehensive evolutionary analysis of E2F, RB and DP (dimerization partners of E2Fs) protein family in representative eukaryotic organisms. Several interesting facts were revealed. First, orthologues of RB, E2F, and DP family are present in several representative unicellular organisms and all multicellular organisms we checked. Second, ancestral E2F, RB genes duplicated before placozoans and bilaterians diverged, thus E2F family was divided into E2F4/5 subgroup (including repressive E2Fs: E2F4 and E2F5) and E2F1/2/3 subgroup (including active E2Fs: E2F1, E2F2 and E2F3), RB family was divided into RB1 subgroup (including RB1) and RBL subgroup (including RBL1 and RBL2). Third, E2F4 and E2F5 share more sequence similarity with the predicted E2F ancestral sequence than E2F1, E2F2 and E2F3; E2F4 and E2F5 also possess lower evolutionary rates and higher purification selection pressures than E2F1, E2F2 and E2F3. Fourth, for RB family, the RBL subgroup proteins possess lower evolutionary rates and higher purification selection pressures compared with RB subgroup proteins in vertebrates, Protein evolutionary rates and purification selection pressures are usually linked with protein functions. We speculated that function conducted by E2F4/5 subgroup and RBL subgroup proteins might mainly represent the ancient function of RB-E2F pathway, and the E2F1/2/3 subgroup proteins and RB1 protein might contribute more to functional diversification in RB-E2F pathway. Our results will enhance the current

  3. Astro-E2 Magnesium Diboride High Current Leads

    NASA Technical Reports Server (NTRS)

    Panek, J. S.; Tuttle, J. G.; Riall, S.; Mustafi, S.; Gray, A.; Edmonds, R.; Marrero, V.

    2003-01-01

    The recent discovery of superconducting properties in MgB_2 and rapid development of small diameter steel-clad wires has opened up the possibility of enhancing the design of the baseline Astro-E2 high current lead assembly. Replacing YBCO filaments with MgB_2 wires and modifying the heat sink location can give much higher margins against quench from temperature oscillations of the 4 K heat sink, although wih some overall thermal penalty. The design and performance of a new lead assembly during flight qualification is discussed, with emphasis on thermal, structural, and electrical test results.

  4. Disorder-dependent valley properties in monolayer WS e2

    NASA Astrophysics Data System (ADS)

    Tran, Kha; Singh, Akshay; Seifert, Joe; Wang, Yiping; Hao, Kai; Huang, Jing-Kai; Li, Lain-Jong; Taniguchi, Takashi; Watanabe, Kenji; Li, Xiaoqin

    2017-07-01

    We investigate the effect of disorder on exciton valley polarization and valley coherence in monolayer WS e2 . By analyzing the polarization properties of photoluminescence, the valley coherence (VC) and valley polarization (VP) are quantified across the inhomogeneously broadened exciton resonance. We find that disorder plays a critical role in the exciton VC, while affecting VP less. For different monolayer samples with disorder characterized by their Stokes shift (SS), VC decreases in samples with higher SS while VP does not follow a simple trend. These two methods consistently demonstrate that VC as defined by the degree of linearly polarized photoluminescence is more sensitive to disorder, motivating further theoretical studies.

  5. Astro-E2 Magnesium Diboride High Current Leads

    NASA Technical Reports Server (NTRS)

    Panek, J. S.; Tuttle, J. G.; Riall, S.; Mustafi, S.; Gray, A.; Edmonds, R.; Marrero, V.

    2003-01-01

    The recent discovery of superconducting properties in MgB_2 and rapid development of small diameter steel-clad wires has opened up the possibility of enhancing the design of the baseline Astro-E2 high current lead assembly. Replacing YBCO filaments with MgB_2 wires and modifying the heat sink location can give much higher margins against quench from temperature oscillations of the 4 K heat sink, although wih some overall thermal penalty. The design and performance of a new lead assembly during flight qualification is discussed, with emphasis on thermal, structural, and electrical test results.

  6. Microsomal prostaglandin E2 synthase-1 inhibitors: a patent review.

    PubMed

    Psarra, Anastasia; Nikolaou, Aikaterini; Kokotou, Maroula G; Limnios, Dimitris; Kokotos, George

    2017-09-01

    Microsomal prostaglandin E2 synthase-1 (mPGES-1) catalyzes the terminal step of prostaglandin E2 (PGE2) generation. It is strongly upregulated in inflamed tissues and overexpressed in tumors and it has been recognized as a key enzyme in inflammatory diseases such as arthritis, atherosclerosis, stroke and cancer. Thus, a great effort has been devoted in developing synthetic mPGES-1 inhibitors as novel anti-inflammatory agents. Areas covered: This review article summarizes the mPGES-1 inhibitors presented in patent literature from 2000 to August 2016 and their biological evaluation, discussing their activities in vitro and in vivo. Expert opinion: The side effects of NSAIDs and COX-2 inhibitors on the gastrointestinal tract and the cardiovascular system showcase the urgent need for the discovery of novel potent and safe anti-inflammatory drugs. mPGES-1 inhibitors may present superior safety in comparison to existing anti-inflammatory drugs. The first synthetic inhibitor of mPGES-1 was reported in 2001 and up to now a variety of structurally different inhibitors has been developed. However, only recently two inhibitors entered clinical trials and none has reached yet the market. More preclinical and clinical studies on mPGES-1 inhibitors are needed to realize if indeed they may become novel agents for the treatment of inflammation and cancer.

  7. Long-acting estrogenic responses of estradiol fatty acid esters.

    PubMed

    Vazquez-Alcantara, M A; Menjivar, M; Garcia, G A; Díaz-Zagoya, J C; Garza-Flores, J

    1989-12-01

    Estradiol esters at C-17 and C-3 with palmitic, stearic and oleic acids were chemically synthesized and then evaluated for their long-acting estrogenic responses in ovariectomized rats. The duration of the biological effects was measured after a single subcutaneous dose of 0.1 mumol of each ester and compared with those observed with 17 beta-estradiol, estradiol 3-benzoate and estradiol 17-enanthate. Vaginal citology, uterophyc action, serum gonadotropins inhibition and 17 beta-estradiol levels were measured 0, 5, 10, 20, 30 and 60 days after injection. The results disclosed that most of the estradiol derivatives evaluated exhibited a long-acting estrogenic action. However, the monoesters at C-17 showed longer effects that monoesters at C-3, while the estradiol diesters exhibited the shortest effects. In addition as shown by its low serum levels, all estradiol esters with unsaturated fatty acids show a decreased E2 absorption. The overall results indicated that esterification of E2 with long chain fatty acids provided long-acting properties to it, being higher with C-17 esters. Whether some of these compounds could be employed in substitutive endocrine therapy remains to be established.

  8. Observing interference effect in binary (e, 2e) of molecules

    NASA Astrophysics Data System (ADS)

    Chen, Xiangjun; Yang, Jing; Shan, Xu; Zhang, Zhe; Tian, Qiguo; Wang, Enliang

    2015-04-01

    We present investigations on the two-center and multi-center interference effects of molecules in binary (e, 2e) experiments. The high energy resolution electron momentum spectroscopy (EMS) measurements on H2 are reported with final vibrational states resolved. The experimental momentum profiles for ionization transitions to the individual final vibrational states of the ion are obtained. The measured and calculated vibrational ratios of the cross sections deviate from Franck-Condon principle, which can be ascribed to the Young-type two-center interference. Furthermore, with the help of our latest version of EMS spectrometer which has considerably higher sensitivity and much wider momentum range from 0 to 8 a.u., we are able to extend our observations to multi-center interference effect in high symmetry molecules like NF3 and CF4 with several oscillation periods included.

  9. Triply differential (e,2e) studies of phenol

    SciTech Connect

    Silva, G. B. da; Neves, R. F. C.; Chiari, L.; Jones, D. B.; Ali, E.; Madison, D. H.; Ning, C. G.; Nixon, K. L.; Lopes, M. C. A.; Brunger, M. J.

    2014-09-28

    We have measured (e,2e) triple differential cross sections (TDCS) for the electron-impact ionisation of phenol with coplanar asymmetrical kinematics for an incident electron energy of 250 eV. Experimental measurements of the angular distribution of the slow outgoing electrons at 20 eV are obtained when the incident electron scatters through angles of −5°, −10°, and −15°, respectively. The TDCS data are compared with calculations performed within the molecular 3-body distorted wave model. In this case, a mixed level of agreement, that was dependent on the kinematical condition being probed, was observed between the theoretical and experimental results in the binary peak region. The experimental intensity of the recoil features under all kinematical conditions was relatively small, but was still largely underestimated by the theoretical calculations.

  10. E-2D Advanced Hawkeye: primary flight display

    NASA Astrophysics Data System (ADS)

    Paolillo, Paul W.; Saxena, Ragini; Garruba, Jonathan; Tripathi, Sanjay; Blanchard, Randy

    2006-05-01

    This paper is a response to the challenge of providing a large area avionics display for the E-2D AHE aircraft. The resulting display design provides a pilot with high-resolution visual information content covering an image area of almost three square feet (Active Area of Samsung display = 33.792cm x 27.0336 cm = 13.304" x 10.643" = 141.596 square inches = 0.983 sq. ft x 3 = 2.95 sq. ft). The avionics display application, design and performance being described is the Primary Flight Display for the E-2D Advanced Hawkeye aircraft. This cockpit display has a screen diagonal size of 17 inches. Three displays, with minimum bezel width, just fit within the available instrument panel area. The significant design constraints of supporting an upgrade installation have been addressed. These constraints include a display image size that is larger than the mounting opening in the instrument panel. This, therefore, requires that the Electromagnetic Interference (EMI) window, LCD panel and backlight all fit within the limited available bezel depth. High brightness and a wide dimming range are supported with a dual mode Cold Cathode Fluorescent Tube (CCFT) and LED backlight. Packaging constraints dictated the use of multiple U shaped fluorescent lamps in a direct view backlight design for a maximum display brightness of 300 foot-Lamberts. The low intensity backlight levels are provided by remote LEDs coupled through a fiber optic mesh. This architecture generates luminous uniformity within a minimum backlight depth. Cross-cockpit viewing is supported with ultra-wide field-of-view performance including contrast and the color stability of an advanced LCD cell design supports. Display system design tradeoffs directed a priority to high optical efficiency for minimum power and weight.

  11. [Therapeutic Drug Monitoring of Valproic Acid in Children: A Prospective Study of The Effect of The Compliance and The Economic Level on the Trough Plasmatic Concentrations and Epileptic Seizures].

    PubMed

    Charfi, Rim; Lakhal, Mohamed; Klouz, Anis; Trabelsi, Sameh; Salouage, Issam

    2015-01-01

    Valproic acid (VA) is a widely used antiepileptic drug. Because of its pharmacokinetic variability and the influence of intrinsic and extrinsic factors such as the treatment compliance, VA therapeutic drug monitoring (TDM) is recommended in children. The aim of this study is to evaluate the effect of treatment compliance and the economic level on VA tough plasmatic concentration (TPC) and epileptic rhythm in children. A one-year prospective study (August 2008-August 2009) concerning children (age≤5 years) regularly treated by VA who had a VA TDM. So, 276 plasmatic samples from 238 children were collected. The children were divided in two groups as following: the group 1 (G1) presenting a good compliance and a reliable questioning and the group 2 (G2) presenting a bad compliance and a non reliable questioning. We evaluated the interindividual variability by correlating the TPC to the dose. Then, we divided the hole group in function of their economic levels (low-medium-high). Sex ratio male/female was 1.3. Median age was 5 years+/-3,9. The mean TPC was 62 µg/mL [0.12-131 µg/mL]. VA TPC were in the therapeutic range (TR) in 62%. Adverse drug reactions were noted in 4.2% of the children. G1 represented 70% of the children and G2, 30%. The TPC were in the TR in 67% of G1 and 51% of G2 (p=0.02). There was a significant difference between the TPC in G1 and G2 (p=0.02).There was no significative difference in the TPC in function of the economic levels. There was no correlation between TPC and the administered doses. The epileptic seizures were more spaced in children with therapeutic TPC than those with TPC in the TR (p=0.002) and in G1 than in G2 (p=0.03). Compliance should be appropriate in order to optimize the TDM rule. A good compliance and a therapeutic TPC allow a better control of epileptic seizures. © 2015 Société Française de Pharmacologie et de Thérapeutique.

  12. Prostaglandin E2 Prevents Disuse-Induced Cortical Bone Loss

    NASA Technical Reports Server (NTRS)

    Jee, Webster S. S.; Akamine, T.; Ke, Hua Zhu; Li, Xiao Jian; Tang, L. Y.; Zeng, Q. Q.

    1992-01-01

    The object of this study was to determine whether prostaglandin E2 (PGE2) can prevent disuse (underloaded)-induced cortical bone loss as well as add extra bone to underloaded bones. Thirteen-month-old retired female Sprague-Dawley breeders served as controls or were subjected to simultaneous right hindlimb immobilization by bandaging and daily subcutaneous doses of 0, 1, 3, or 6 mg PGE2/kg/d for two and six weeks. Histomorphometric analyses were performed on double-fluorescent labeled undecalcified tibial shaft sections (proximal to the tibiofibular junction). Disuse-induced cortical bone loss occurred by enlarging the marrow cavity and increasing intracortical porosity. PGE2 treatment of disuse shafts further increased intracortical porosity above that in disuse alone controls. This bone loss was counteracted by enhancement of periosteal and corticoendosteal bone formation. Stimulation of periosteal and corticoendosteal bone formation slightly enlarged the total tissue (cross-sectional) area and inhibited marrow cavity enlargement. These PGE2-induced activities netted the same percentage of cortical bone with a different distribution than the beginning and age related controls. These findings indicate the PGE2-induced increase in bone formation compensated for the disuse and PGE2-induced bone loss, and thus prevented immobilization induced bone loss.

  13. Prostaglandin E2-induced inflammation: Relevance of prostaglandin E receptors.

    PubMed

    Kawahara, Kohichi; Hohjoh, Hirofumi; Inazumi, Tomoaki; Tsuchiya, Soken; Sugimoto, Yukihiko

    2015-04-01

    Prostaglandin E2 (PGE2) is one of the most typical lipid mediators produced from arachidonic acid (AA) by cyclooxygenase (COX) as the rate-limiting enzyme, and acts on four kinds of receptor subtypes (EP1-EP4) to elicit its diverse actions including pyrexia, pain sensation, and inflammation. Recently, the molecular mechanisms underlying the PGE2 actions mediated by each EP subtype have been elucidated by studies using mice deficient in each EP subtype as well as several compounds highly selective to each EP subtype, and their findings now enable us to discuss how PGE2 initiates and exacerbates inflammation at the molecular level. Here, we review the recent advances in PGE2 receptor research by focusing on the activation of mast cells via the EP3 receptor and the control of helper T cells via the EP2/4 receptor, which are the molecular mechanisms involved in PGE2-induced inflammation that had been unknown for many years. We also discuss the roles of PGE2 in acute inflammation and inflammatory disorders, and the usefulness of anti-inflammatory therapies that target EP receptors. This article is part of a Special Issue entitled "Oxygenated metabolism of PUFA: analysis and biological relevance". Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Prevotella intermedia induces prostaglandin E2 via multiple signaling pathways.

    PubMed

    Guan, S-M; Fu, S-M; He, J-J; Zhang, M

    2011-01-01

    Prostaglandin E(2) (PGE(2)) plays important roles in the bone resorption of inflammatory diseases such as rheumatoid arthritis and periodontitis via specific prostaglandin receptors (i.e., EP1-EP4). In this study, the authors examined whether Prevotella intermedia regulates PGE(2) production and EP expression in human periodontal ligament fibroblasts (hPDLs); they also explored the potential signaling pathways involved in PGE(2) production. P. intermedia induced PGE(2) production and cyclooxygenase-2 (COX-2) expression in a dose- and time-dependent manner. Indomethacin and NS-398 completely abrogated the P. intermedia-induced PGE(2) production without modulating COX-2 expression. Specific inhibitors of extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38, phosphatidylinositol 3-kinase, and protein kinase C--but not c-AMP and protein kinase A--significantly attenuated the P. intermedia-induced COX-2 and PGE(2) expression. P. intermedia reduced EP1 expression in a concentration- and time-dependent manner. The results indicate that the COX-2-dependent induction of PGE(2) by P. intermedia in hPDLs is mediated by multiple signaling pathways.

  15. Plasmon resonant (e, 2e) spectroscopy on Be(0001)

    NASA Astrophysics Data System (ADS)

    Di Filippo, Gianluca; Sbaraglia, Damiano; Ruocco, Alessandro; Stefani, Giovanni

    2016-10-01

    We investigated the mechanisms of secondary electron (SE) emission from Be(0001) by impact of 100 and 150 eV electrons. We made use of (e, 2e) spectroscopy to disentangle the different SE production mechanisms. We observed a large increase in the SE yield when the energy loss of the primary electron equals the characteristic energy of volume and surface plasmons. The line shape of the SE spectrum associated with plasmon excitation reveals that one relevant emission mechanism corresponds to direct single-particle excitation in which the plasmon energy and momentum are transferred to a valence band electron of the solid. The contributions to the SE yield associated with surface and volume plasmon excitation are comparable in the case of specular geometry, where the projectile momentum is mainly transferred perpendicular to the surface. On the contrary, the emission of SEs associated with surface plasmon excitation is significantly enhanced when the exchanged momentum lies close to the surface plane and electrons are emitted from Be surface state. This reflects the increased sensitivity to surface modes of the latter geometry. Finally, the coupling between the direct ionization channel and the plasmon-assisted one results in a resonant increase of the secondary emission.

  16. STS-70 Launch - Nikon E-2 Digital Image

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This test image was taken with a Nikon E-2 Digital Imaging System camera and are provided courtesy of Nikon (GIF 450x450 JPEG 1280x1000): The second Shuttle launch in 16 days hurtles off the pad into a sweltering summer sky. The unstable weather typical to Florida in the summertime didn't have a chance to coalesce and impact this morning's launch window, and the Space Shuttle Discovery began its planned seven-day, 22-hour flight on Mission STS-70 from Launch Pad 39B at 9:41:55.078 a.m. EDT, just seconds off schedule. On board for Discovery's 21st spaceflight are a crew of five: Commander Terence 'Tom' Henricks; Pilot Kevin R. Kregel; and Mission Specialists Nancy Jane Currie, Donald A. Thomas and Mary Ellen Weber. The crew's primary objective during the 70th Shuttle flight is to deploy the Tracking and Data Relay Satellite (TDRS-G), which will join a constellation of other TDRS spacecraft already on orbit. TDRS-G is destined to become an on- orbit, fully operational 'ready reserve' satellite, available along with one other ready reserve TDRS spacecraft to back up the two primary TDRS satellites positions, TDRS East over the Atlantic Ocean and TDRS West over the Pacific. Assured capability of the TDRS communications network is essential for linking Earth-orbiting spacecraft such as the Shuttle and the Hubble Space Telescope with the ground.

  17. STS-70 Launch - Nikon E-2 Digital Image

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This test images was taken with a Nikon E-2 Digital Imaging System camera and are provided courtesy of Nikon (GIF 450x450 JPEG 1280x1000): The second Shuttle launch in 16 days hurtles off the pad into a sweltering summer sky. The unstable weather typical to Florida in the summertime didn't have a chance to coalesce and impact this morning's launch window, and the Space Shuttle Discovery began its planned seven-day, 22-hour flight on Mission STS-70 from Launch Pad 39B at 9:41:55.078 a.m. EDT, just seconds off schedule. On board for Discovery's 21st spaceflight are a crew of five: Commander Terence 'Tom' Henricks; Pilot Kevin R. Kregel; and Mission Specialists Nancy Jane Currie, Donald A. Thomas and Mary Ellen Weber. The crew's primary objective during the 70th Shuttle flight is to deploy the Tracking and Data Relay Satellite (TDRS-G), which will join a constellation of other TDRS spacecraft already on orbit. TDRS-G is destined to become an on- orbit, fully operational 'ready reserve' satellite, available along with one other ready reserve TDRS spacecraft to back up the two primary TDRS satellites positions, TDRS East over the Atlantic Ocean and TDRS West over the Pacific. Assured capability of the TDRS communications network is essential for linking Earth-orbiting spacecraft such as the Shuttle and the Hubble Space Telescope with the ground.

  18. Functional interactions between ubiquitin E2 enzymes and TRIM proteins.

    PubMed

    Napolitano, Luisa M; Jaffray, Ellis G; Hay, Ronald T; Meroni, Germana

    2011-03-01

    The TRIM (tripartite motif) family of proteins is characterized by the presence of the tripartite motif module, composed of a RING domain, one or two B-box domains and a coiled-coil region. TRIM proteins are involved in many cellular processes and represent the largest subfamily of RING-containing putative ubiquitin E3 ligases. Whereas their role as E3 ubiquitin ligases has been presumed, and in several cases established, little is known about their specific interactions with the ubiquitin-conjugating E2 enzymes or UBE2s. In the present paper, we report a thorough screening of interactions between the TRIM and UBE2 families. We found a general preference of the TRIM proteins for the D and E classes of UBE2 enzymes, but we also revealed very specific interactions between TRIM9 and UBE2G2, and TRIM32 and UBE2V1/2. Furthermore, we demonstrated that the TRIM E3 activity is only manifest with the UBE2 with which they interact. For most specific interactions, we could also observe subcellular co-localization of the TRIM involved and its cognate UBE2 enzyme, suggesting that the specific selection of TRIM-UBE2 pairs has physiological relevance. Our findings represent the basis for future studies on the specific reactions catalysed by the TRIM E3 ligases to determine the fate of their targets.

  19. Prostaglandin E2 As a Modulator of Viral Infections

    PubMed Central

    Sander, Willem J.; O'Neill, Hester G.; Pohl, Carolina H.

    2017-01-01

    Viral infections are a major cause of infectious diseases worldwide. Inflammation and the immune system are the major host defenses against these viral infection. Prostaglandin E2 (PGE2), an eicosanoid generated by cyclooxygenases, has been shown to modulate inflammation and the immune system by regulating the expression/concentration of cytokines. The effect of PGE2 on viral infection and replication is cell type- and virus-family-dependent. The host immune system can be modulated by PGE2, with regards to immunosuppression, inhibition of nitrogen oxide (NO) production, inhibition of interferon (IFN) and apoptotic pathways, and inhibition of viral receptor expression. Furthermore, PGE2 can play a role in viral infection directly by increasing the production and release of virions, inhibiting viral binding and replication, and/or stimulating viral gene expression. PGE2 may also have a regulatory role in the induction of autoimmunity and in signaling via Toll-like receptors. In this review the known effects of PGE2 on the pathogenesis of various infections caused by herpes simplex virus, rotavirus, influenza A virus and human immunodeficiency virus as well the therapeutic potential of PGE2 are discussed. PMID:28261111

  20. Prostaglandin E2 regulates vertebrate haematopoietic stem cell homeostasis

    PubMed Central

    North, Trista E.; Goessling, Wolfram; Walkley, Carl R.; Lengerke, Claudia; Kopani, Kamden R.; Lord, Allegra M.; Weber, Gerhard J.; Bowman, Teresa V.; Jang, Il-Ho; Grosser, Tilo; FitzGerald, Garret A.; Daley, George Q.; Orkin, Stuart H.; Zon, Leonard I.

    2009-01-01

    Haematopoietic stem cell (HSC) homeostasis is tightly controlled by growth factors, signalling molecules and transcription factors. Definitive HSCs derived during embryogenesis in the aorta-gonad-mesonephros region subsequently colonize fetal and adult haematopoietic organs1,2. To identify new modulators of HSC formation and homeostasis, a panel of biologically active compounds was screened for effects on stem cell induction in the zebrafish aorta-gonad-mesonephros region. Here, we show that chemicals that enhance prostaglandin (PG) E2 synthesis increased HSC numbers, and those that block prostaglandin synthesis decreased stem cell numbers. The cyclooxygenases responsible for PGE2 synthesis were required for HSC formation. A stable derivative of PGE2 improved kidney marrow recovery following irradiation injury in the adult zebrafish. In murine embryonic stem cell differentiation assays, PGE2 caused amplification of multipotent progenitors. Furthermore, ex vivo exposure to stabilized PGE2 enhanced spleen colony forming units at day 12 post transplant and increased the frequency of long-term repopulating HSCs present in murine bone marrow after limiting dilution competitive transplantation. The conserved role for PGE2 in the regulation of vertebrate HSC homeostasis indicates that modulation of the prostaglandin pathway may facilitate expansion of HSC number for therapeutic purposes. PMID:17581586

  1. (e,2e) ionization studies of diatomic & triatomic molecules

    NASA Astrophysics Data System (ADS)

    Nixon, Kate; Murray, Andrew; Kaiser, Christian; Al-Hagan, Ola; Colgan, James; Madison, Don

    2009-10-01

    (e,2e) studies yield the most detailed experimental data on electron impact ionization of atomic & molecular targets for comparison to quantum collision theories. Coincidence techniques are here used to measure the probability of ionization as a function of the incident electron scattering angle and angle of the electron ejected from the target. In Manchester we study this process at low energies, where the ionization probability is greatest & the interaction most complex. We recently considered ionization of simple molecules (eg H2 & H2O) from a coplanar geometry to the perpendicular plane[1-4], and have discovered the interaction is far more complex than for ionization of atoms [5]. We here present comparisons between theory & experiment, and discuss new methods we intend to implement to study ionization from laser-aligned atoms & molecules. References. [1] J Colgan et al Phys Rev Lett 101 233201 (2008) [2] O Al-Hagan et al Nature Physics 5 59 (2009) [3] J Colgan et al Phys Rev A 79 052704 (2009) [4] C Kaiser et al J Phys B 40 2563 (2007) [5] A J Murray et al J Phys B 36 4875 (2003) & references therein

  2. Removal of selected pharmaceuticals and personal care products (PPCPs) and endocrine-disrupting chemicals (EDCs) during sand filtration and ozonation at a municipal sewage treatment plant.

    PubMed

    Nakada, Norihide; Shinohara, Hiroyuki; Murata, Ayako; Kiri, Kentaro; Managaki, Satoshi; Sato, Nobuyuki; Takada, Hideshige

    2007-11-01

    We investigated the efficiencies of removal of 24 pharmaceutically active compounds (PhACs) during sand filtration and ozonation in an operating municipal sewage treatment plant (STP). The target compounds were 2 phenolic antiseptics (thymol, triclosan), 5 acidic analgesics or anti-inflammatories (ibuprofen, naproxen, ketoprofen, fenoprofen, mefenamic acid), 4 amide pharmaceuticals (propyphenazone, crotamiton, carbamazepine, diethyltoluamide), 7 antibiotics (sulfapyridine, sulfamethoxazole, trimethoprim, azithromycin, erythromycin anhydride, clarithromycin, roxithromycin), 3 phenolic endocrine-disrupting chemicals (EDCs) (nonylphenol:NP, octylphenol:OP, bisphenol A:BPA) and 3 natural estrogens (17 beta-estradiol:E2, estrone:E1, estriol:E3). Ozonation removed approximately 80% or more of the phenolic antiseptics, crotamiton, sulfonamide and macrolide antibiotics, and 17 beta-estradiol. Their removal is discussed in terms of chemical structure. The study ascertained the validity of ozonation mechanisms proposed by previous studies in an actually running STP. Compounds with a CC double bond or an aromatic structure with electron donors (e.g., phenol, alkyl, methoxy, or non-protonated amine) were susceptible to ozonation. Compounds with amide structures were resistant. Removal of the PhACs during sand filtration was generally inefficient, probably because of their low hydrophobicities. The combination of ozonation and sand filtration with activated sludge treatment gave efficient removal (>80%) of all the target compounds except carbamazepine and diethyltoluamide. Among all the steps in the plant, ozonation contributed substantially to overall removal of naproxen, ketoprofen, triclosan, crotamiton, sulfapyridine, macrolide antibiotics, and estrone.

  3. Detection of hormone active chemicals using genetically engineered yeast cells and microfluidic devices with interdigitated array electrodes.

    PubMed

    Ino, Kosuke; Kitagawa, Yusuke; Watanabe, Tsuyoshi; Shiku, Hitoshi; Koide, Masahiro; Itayama, Tomoaki; Yasukawa, Tomoyuki; Matsue, Tomokazu

    2009-10-01

    Endocrine disruptors that act like hormones in the endocrine system might have toxic effects. Therefore, it is important to develop a portable device that can detect hormone active chemicals in samples rapidly and easily. In this study, a microfluidic device was developed for the detection of hormone active chemicals using genetically engineered yeast cells. The yeast cells were used as biosensors since they were genetically engineered to respond to the presence of hormone active chemicals by synthesizing beta-galactosidase (beta-gal). For achieving further sensitivity, we incorporated interdigitated array (IDA) electrodes (width, 1.2 microm; gap, 0.8 microm) with 40 electrode fingers into the analytical chamber of the microfluidic device. The yeast cells precultured with a hormone active chemical, 17beta-estradiol (E2), were trapped from the main channel of the device to the analytical camber by electrophoresis. After trapping in the analytical chamber, we performed electrochemical detection of beta-gal induced in the yeast cells with the IDA electrodes. Actually, electrochemical detection was performed on p-aminophenol that was converted from p-aminophenyl-beta-D-galactopyranoside with beta-gal. The electrochemical signals from the yeast cells precultured with 17beta-estradiol were successfully detected with the device. Furthermore, the inhibitory effects of antagonists such as tamoxifen were also detected electrochemically by using the device. Thus, the present microfluidic device can be used for highly sensitive detection of hormone active chemicals.

  4. Estrogenic effects of mixtures of phyto- and synthetic chemicals on uterine growth of prepubertal rats.

    PubMed

    van Meeuwen, J A; van den Berg, M; Sanderson, J T; Verhoef, A; Piersma, A H

    2007-04-25

    Through the diet humans are exposed to many weak estrogenic phytochemicals (PCs) and synthetic chemicals (SCs), but most experimental studies used individual compounds rather than mixtures. Estrogenic effects were determined in the rat juvenile uterotrophic assay using a predefined phytochemical mixture (PCmix) containing coumestrol, genistein, naringenin, (+,-)catechin, (-,-)epicatechin and quercetin, and a predefined synthetic chemical mixture (SCmix) containing nonyl-, and octylphenol, beta-hexachlorocyclohexane, methoxychlor, bisphenol A and dibutylphthalate. The mixture composition was based on human dietary uptake and actual ratios in serum. 17beta-Estradiol and genistein were also tested individually. It was found that combinations of phytoestrogens and exogenous 17beta-estradiol act additive. In contrast SCmix, inactive by itself even at high dose levels relative to human exposure, caused no synergistic or antagonistic uterotrophic effect with E(2) and/or the PCmix. Based on ED(05) and ED(01) values of the PCmix the margin of exposure in regular human diet for a uterotrophic effect is estimated many orders of magnitude. However, food supplements with phytochemicals might bring individual exposure around ED(05) and ED(01) values of the PCmix. Based on the results of our study the contribution of SCs to total estrogenicity in human diet can probably be neglected.

  5. Prostaglandin E2 Reduces Cardiac Contractility via EP3 Receptor

    PubMed Central

    Gu, Xiaosong; Xu, Jiang; Zhu, Liping; Bryson, Timothy; Yang, Xiao-Ping; Peterson, Edward; Harding, Pamela

    2016-01-01

    Background Prostaglandin E2 (PGE2) EP receptors EP3 and EP4 signal via decreased and increased cAMP production, respectively. Previously we reported that cardiomyocyte-specific EP4 KO mice develop dilated cardiomyopathy with reduced ejection fraction. We thus hypothesized that PGE2 increases contractility via EP4 but decreases contractility via EP3. Methods and Results The effects of PGE2 and the EP1/EP3 agonist sulprostone on contractility were examined in the mouse langendorff preparation and in adult mouse cardiomyocytes (AVM). Isolated hearts of adult male C57Bl/6 mice were perfused with PGE2 (10−6M) or sulp (10−6M) and compared to vehicle. Both PGE2 and sulprostone decreased +dp/dt (p<0.01) and left ventricular developed pressure, LVDP, (p<0.001) with reversal by an EP3 antagonist. In contrast, the EP4 agonist had the opposite effect. AVM contractility was also reduced after treatment with either PGE2 or sulprostone for 10 min. We then examined the acute effects of PGE2, sulprostone and the EP4 agonist on expression of phosphorylated phospholamban (PLN) and SERCA2a in AVM using Western blot. Treatment with either PGE2 or sulprostone decreased expression of phosphorylated PLN corrected to total PLN whereas treatment with the EP4 agonist had the opposite effect. SERCA2a expression was unaffected. Finally, we examined the effect of these compounds in vivo using pressure volume loops. Both PGE2 and sulprostone decreased +dp/dt while the EP4 agonist increased +dp/dt. Conclusions Contractility is reduced via the EP3 receptor but increased via EP4. These effects may be mediated through changes in PLN phosphorylation and has relevance to detrimental effects of inflammation. PMID:27502370

  6. Prostaglandin E2 Reduces Cardiac Contractility via EP3 Receptor.

    PubMed

    Gu, Xiaosong; Xu, Jiang; Zhu, Liping; Bryson, Timothy; Yang, Xiao-Ping; Peterson, Edward; Harding, Pamela

    2016-08-01

    Prostaglandin E2 (PGE2) EP receptors EP3 and EP4 signal via decreased and increased cAMP production, respectively. Previously, we reported that cardiomyocyte-specific EP4 knockout mice develop dilated cardiomyopathy with reduced ejection fraction. Thus, we hypothesized that PGE2 increases contractility via EP4 but decreases contractility via EP3. The effects of PGE2 and the EP1/EP3 agonist sulprostone on contractility were examined in the mouse Langendorff preparation and in adult mouse cardiomyocytes. Isolated hearts of adult male C57Bl/6 mice were perfused with PGE2 (10(-6) M) or sulprostone (10(-6) M) and compared with vehicle. Both PGE2 and sulprostone decreased +dp/dt (P<0.01) and left ventricular developed pressure (P<0.001) with reversal by an EP3 antagonist. In contrast, the EP4 agonist had the opposite effect. Adult mouse cardiomyocytes contractility was also reduced after treatment with either PGE2 or sulprostone for 10 minutes. We then examined the acute effects of PGE2, sulprostone, and the EP4 agonist on expression of phosphorylated phospholamban and sarcoendoplasmic reticulum Ca(2+)-ATPase 2a in adult mouse cardiomyocytes using Western blot. Treatment with either PGE2 or sulprostone decreased expression of phosphorylated phospholamban corrected to total phospholamban, whereas treatment with the EP4 agonist had the opposite effect. Sarcoendoplasmic reticulum Ca(2+)-ATPase 2a expression was unaffected. Finally, we examined the effect of these compounds in vivo using pressure-volume loops. Both PGE2 and sulprostone decreased +dp/dt, whereas the EP4 agonist increased +dp/dt. Contractility is reduced via the EP3 receptor but increased via EP4. These effects may be mediated through changes in phospholamban phosphorylation and has relevance to detrimental effects of inflammation. © 2016 American Heart Association, Inc.

  7. Tropical Cyclones in the GISS ModelE2

    NASA Technical Reports Server (NTRS)

    Camargo, Suzana J.; Sobel, Adam H.; Del Genio, Anthony; Jonas, Jeffrey A.; Kelley, Maxwell; Lu, Yun; Shaevitz, Daniel; Henderson, Naomi

    2016-01-01

    The authors describe the characteristics of tropical cyclone (TC) activity in the GISS general circulation ModelE2 with a horizontal resolution 1deg x 1deg. Four model simulations are analyzed. In the first, the model is forced with sea surface temperature (SST) from the recent historical climatology. The other three have different idealized climate change simulations, namely (1) a uniform increase of SST by 2 deg., (2) doubling of the CO2 concentration and (3) a combination of the two. These simulations were performed as part of the US Climate Variability and Predictability Program Hurricane Working Group. Diagnostics of standard measures of TC activity are computed from the recent historical climatological SST simulation and compared with the same measures computed from observations. The changes in TC activity in the three idealized climate change simulations, by comparison with that in the historical climatological SST simulation, are also described. Similar to previous results in the literature, the changes in TC frequency in the simulation with a doubling CO2 and an increase in SST are approximately the linear sum of the TC frequency in the other two simulations. However, in contrast with previous results, in these simulations the effects of CO2 and SST on TC frequency oppose each other. Large-scale environmental variables associated with TC activity are then analyzed for the present and future simulations. Model biases in the large-scale fields are identified through a comparison with ERA-Interim reanalysis. Changes in the environmental fields in the future climate simulations are shown and their association with changes in TC activity discussed.

  8. Tropical Cyclones in the GISS ModelE2

    NASA Technical Reports Server (NTRS)

    Camargo, Suzana J.; Sobel, Adam H.; Del Genio, Anthony; Jonas, Jeffrey A.; Kelley, Maxwell; Lu, Yun; Shaevitz, Daniel; Henderson, Naomi

    2016-01-01

    The authors describe the characteristics of tropical cyclone (TC) activity in the GISS general circulation ModelE2 with a horizontal resolution 1deg x 1deg. Four model simulations are analyzed. In the first, the model is forced with sea surface temperature (SST) from the recent historical climatology. The other three have different idealized climate change simulations, namely (1) a uniform increase of SST by 2 deg., (2) doubling of the CO2 concentration and (3) a combination of the two. These simulations were performed as part of the US Climate Variability and Predictability Program Hurricane Working Group. Diagnostics of standard measures of TC activity are computed from the recent historical climatological SST simulation and compared with the same measures computed from observations. The changes in TC activity in the three idealized climate change simulations, by comparison with that in the historical climatological SST simulation, are also described. Similar to previous results in the literature, the changes in TC frequency in the simulation with a doubling CO2 and an increase in SST are approximately the linear sum of the TC frequency in the other two simulations. However, in contrast with previous results, in these simulations the effects of CO2 and SST on TC frequency oppose each other. Large-scale environmental variables associated with TC activity are then analyzed for the present and future simulations. Model biases in the large-scale fields are identified through a comparison with ERA-Interim reanalysis. Changes in the environmental fields in the future climate simulations are shown and their association with changes in TC activity discussed.

  9. Prostaglandin E2 increases the skeletal response to mechanical loading

    NASA Technical Reports Server (NTRS)

    Tang, L. Y.; Cullen, D. M.; Yee, J. A.; Jee, W. S.; Kimmel, D. B.

    1997-01-01

    The study tested the influence of prostaglandin E2 (PGE2) on the skeletal response to increased in vivo mechanical loading through a four-point bending device. One hundred and twenty Sprague-Dawley female rats (6 months old, 354 +/- 34 g) were divided into 12 groups to accommodate all possible combinations of doses of loads (25, 30, or 35 N) and PGE2 (0, 0.1, 0.3, or 1 mg/kg). Rats received subcutaneous injections of PGE2 daily and in vivo loading of the right tibia every Monday, Wednesday, and Friday for four weeks. Histomorphometric analysis of the periosteal and endocortical surfaces following in vivo dual fluorochrome labeling was performed on both the loaded region of the right tibial diaphysis and a similar region of the left tibial diaphysis. Without PGE2, the threshold for loading to stimulate bone formation was 30 N (peak strain 1360 mu epsilon) at the periosteal surface and 25 N (peak strain 580 mu epsilon) at the endocortical surface. Without loading, the minimum dose of PGE2 to stimulate bone formation at all surfaces was 1 mg/kg/day. When 1 mg/kg/day PGE2 was combined with the minimum effective load, an additive effect of PGE2 and loading on bone formation was observed at the endocortical surface, but a synergistic effect was noted at the periosteal surface. No combined effect of ineffective doses of loading and PGE2 was found. A synergistic effect at peak strains of approximately 1625 mu epsilon on the periosteal surface could suggest either the involvement of locally produced growth factors or autoregulation of endogenous synthesis of PGE2 by exogenously administered PGE2.

  10. Prostaglandin E2 increases the skeletal response to mechanical loading

    NASA Technical Reports Server (NTRS)

    Tang, L. Y.; Cullen, D. M.; Yee, J. A.; Jee, W. S.; Kimmel, D. B.

    1997-01-01

    The study tested the influence of prostaglandin E2 (PGE2) on the skeletal response to increased in vivo mechanical loading through a four-point bending device. One hundred and twenty Sprague-Dawley female rats (6 months old, 354 +/- 34 g) were divided into 12 groups to accommodate all possible combinations of doses of loads (25, 30, or 35 N) and PGE2 (0, 0.1, 0.3, or 1 mg/kg). Rats received subcutaneous injections of PGE2 daily and in vivo loading of the right tibia every Monday, Wednesday, and Friday for four weeks. Histomorphometric analysis of the periosteal and endocortical surfaces following in vivo dual fluorochrome labeling was performed on both the loaded region of the right tibial diaphysis and a similar region of the left tibial diaphysis. Without PGE2, the threshold for loading to stimulate bone formation was 30 N (peak strain 1360 mu epsilon) at the periosteal surface and 25 N (peak strain 580 mu epsilon) at the endocortical surface. Without loading, the minimum dose of PGE2 to stimulate bone formation at all surfaces was 1 mg/kg/day. When 1 mg/kg/day PGE2 was combined with the minimum effective load, an additive effect of PGE2 and loading on bone formation was observed at the endocortical surface, but a synergistic effect was noted at the periosteal surface. No combined effect of ineffective doses of loading and PGE2 was found. A synergistic effect at peak strains of approximately 1625 mu epsilon on the periosteal surface could suggest either the involvement of locally produced growth factors or autoregulation of endogenous synthesis of PGE2 by exogenously administered PGE2.

  11. p53 Suppresses E2F1-dependent PLK1 expression upon DNA damage by forming p53-E2F1-DNA complex.

    PubMed

    Zhou, Zhe; Cao, Ji-Xiang; Li, Shu-Yan; An, Guo-Shun; Ni, Ju-Hua; Jia, Hong-Ti

    2013-12-10

    E2F1 is implicated in transcriptional activation of polo-like kinase-1 (PLK1), but yet the mechanism is not fully understood. PLK1 suppression plays an important checkpoint role in response to DNA damage. Suppression of the PLK1 gene by binding of p53 to upstream p53RE2 element in the promoter has been recently revealed. Here we report another mechanism, in which p53 interacts with E2F1 to form p53-E2F1-DNA complex repressing E2F1-dependent PLK1 expression. PLK1 was downregulated in cisplatin exposed HCT116p53(+/+) but not HCT116p53(-/-) cells, indicating p53-suppressed PLK1 upon DNA damage. Co-transfection and reporter enzyme assays revealed that p53 suppressed but E2F1 promoted PLK1 gene activation. 5'-Deletion and substitution mutations showed multiple positive cis-elements residing in the PLK1 promoter, of which at least two E2F1 sites at positions -75/-68 and -40/-32 were required for the full activity of the promoter. Combination of 5'-deletion and substitution mutations with over-expression of p53 showed that suppression of the PLK1 gene by p53 was E2F1-dependent: mutation of the E2F1 site at position -75/-68 partially abrogated suppression activity of p53; mutation of E2F1 site at position -40/-32 released from p53 suppression of PLK1 gene completely. Co-immunoprecipitation and electrophoretic mobility shift assay showed that DNA damage promoted p53-E2F1 interaction, thereby creating a p53-E2F1 complex assembly on the PLK1 promoter in vitro. The in vivo formation of p53-E2F1-PLK1 promoter complex upon DNA damage was further evidenced by chromatin immunoprecipitation (ChIP) and re-ChIP. In addition, we showed that suppression of PLK1 by p53 promoted apoptosis. Our data suggest that p53 may interact with E2F1 to form p53-E2F1-DNA complex suppressing E2F1-dependent PLK1 expression. The model of p53 action on E2F1-activated PLK1 gene may explain at least partly how p53 as a suppressor regulates the downstream effects of E2F1 in cellular stresses including DNA

  12. Feedback regulation between atypical E2Fs and APC/CCdh1 coordinates cell cycle progression.

    PubMed

    Boekhout, Michiel; Yuan, Ruixue; Wondergem, Annelotte P; Segeren, Hendrika A; van Liere, Elsbeth A; Awol, Nesibu; Jansen, Imke; Wolthuis, Rob M F; de Bruin, Alain; Westendorp, Bart

    2016-03-01

    E2F transcription factors control the oscillating expression pattern of multiple target genes during the cell cycle. Activator E2Fs, E2F1-3, induce an upswing of E2F targets, which is essential for the G1-to-S phase transition, whereas atypical E2Fs, E2F7 and E2F8, mediate a downswing of the same targets during late S, G2, and M phases. Expression of atypical E2Fs is induced by E2F1-3, but it is unknown how atypical E2Fs are inactivated in a timely manner. Here, we demonstrate that E2F7 and E2F8 are substrates of the anaphase-promoting complex/cyclosome (APC/C). Removal of CDH1, or mutating the CDH1-interacting KEN boxes, stabilized E2F7/8 from anaphase onwards and during G1. Expressing KEN mutant E2F7 during G1 impairs S phase entry and eventually results in cell death. Furthermore, we show that E2F8, but not E2F7, interacts also with APC/C(C) (dc20). Importantly, atypical E2Fs can activate APC/C(C) (dh1) by repressing its inhibitors cyclin A, cyclin E, and Emi1. In conclusion, we discovered a feedback loop between atypical E2Fs and APC/C(C) (dh1), which ensures balanced expression of cell cycle genes and normal cell cycle progression. © 2016 The Authors.

  13. The atypical E2F family member E2F7 couples the p53 and RB pathways during cellular senescence.

    PubMed

    Aksoy, Ozlem; Chicas, Agustin; Zeng, Tianying; Zhao, Zhen; McCurrach, Mila; Wang, Xiaowo; Lowe, Scott W

    2012-07-15

    Oncogene-induced senescence is an anti-proliferative stress response program that acts as a fail-safe mechanism to limit oncogenic transformation and is regulated by the retinoblastoma protein (RB) and p53 tumor suppressor pathways. We identify the atypical E2F family member E2F7 as the only E2F transcription factor potently up-regulated during oncogene-induced senescence, a setting where it acts in response to p53 as a direct transcriptional target. Once induced, E2F7 binds and represses a series of E2F target genes and cooperates with RB to efficiently promote cell cycle arrest and limit oncogenic transformation. Disruption of RB triggers a further increase in E2F7, which induces a second cell cycle checkpoint that prevents unconstrained cell division despite aberrant DNA replication. Mechanistically, E2F7 compensates for the loss of RB in repressing mitotic E2F target genes. Together, our results identify a causal role for E2F7 in cellular senescence and uncover a novel link between the RB and p53 pathways.

  14. The atypical E2F family member E2F7 couples the p53 and RB pathways during cellular senescence

    PubMed Central

    Aksoy, Ozlem; Chicas, Agustin; Zeng, Tianying; Zhao, Zhen; McCurrach, Mila; Wang, Xiaowo; Lowe, Scott W.

    2012-01-01

    Oncogene-induced senescence is an anti-proliferative stress response program that acts as a fail-safe mechanism to limit oncogenic transformation and is regulated by the retinoblastoma protein (RB) and p53 tumor suppressor pathways. We identify the atypical E2F family member E2F7 as the only E2F transcription factor potently up-regulated during oncogene-induced senescence, a setting where it acts in response to p53 as a direct transcriptional target. Once induced, E2F7 binds and represses a series of E2F target genes and cooperates with RB to efficiently promote cell cycle arrest and limit oncogenic transformation. Disruption of RB triggers a further increase in E2F7, which induces a second cell cycle checkpoint that prevents unconstrained cell division despite aberrant DNA replication. Mechanistically, E2F7 compensates for the loss of RB in repressing mitotic E2F target genes. Together, our results identify a causal role for E2F7 in cellular senescence and uncover a novel link between the RB and p53 pathways. PMID:22802529

  15. E2 protein cage as a multifunctional nanoplatform

    NASA Astrophysics Data System (ADS)

    Dalmau Mallorqui, Merce

    Caged protein systems such as viral capsids, heat shock proteins, and ferritin are spherical structures that occur naturally in living organisms and are a growing class of biomimetic templates used to create new materials in nanotechnology. Such systems have been proposed as general drug carriers since they form highly symmetric nanoscale architectures that offer the potential to be tailored according to the desired application. Within this framework, this dissertation focuses on the design and development of a new drug delivery nanoplatform based on the E2 subunit of the pyruvate dehydrogenase protein from Bacillus stearothermophilus. This scaffold forms a 25-nm nanocapsule structure with a hollow cavity. We produced a variant of this protein consisting only of the structural core, and found the thermostability of this self-assembled scaffold to be unusually high, with an onset unfolding temperature of 81.1 +/- 0.9°C and an apparent midpoint unfolding temperature of 91.4 +/- 1.4°C. To evaluate the potential of this scaffold for encapsulation of guest molecules in the internal cavity, we made variants which altered the physicochemical properties of the hollow internal surface. These mutants, yielding up to 240 mutations within this cavity, assembled into correct architectures and exhibited high thermostability that was also comparable to the wild-type scaffold. To show the applicability of this scaffold we coupled two drug-like small molecules to the internal cavity. We also developed a new strategy for encapsulation of small hydrophobic drug molecules. This method is based on hydrophobic differences between the interior cavity and the external buffer to nucleate drug-like agents inside the protein cage. We demonstrate that internal mutations can introduce non-native functionality and enable molecular encapsulation within the cavity while still retaining the dodecahedral structure. Another surface amenable to modifications is the interface between subunits. Such

  16. Prostaglandin E2 in human placenta: its vascular effects and activation of prostaglandin E2 formation by nicotine and cotinine.

    PubMed

    Rama Sastry, B V; Hemontolor, M E; Olenick, M

    1999-02-01

    Tobacco smoking by pregnant women increases the frequency of spontaneous abortions and preterm births. Human labor is associated with enhanced intrauterine phospholipid metabolism and production of prostaglandin E2 (PGE2) which induces labor, initiates uterine contractions and maintains the homeostasis of placental blood flow. Therefore, we studied: (a) the influence of nicotine and cotinine on the effects of PGE2 on placental vasculature in perfused human placental cotyledon, and (b) the activation of placental phospholipase A2 (PLA2) by nicotine and cotinine using 1-palmitoyl-2-[1-14C]arachidonyl-phosphatidylethanolamine (PE, 2.2 nmol) as substrate. These studies revealed that: (1) increasing concentrations of PGE2 (10- 150 ng/ml) increased umbilical perfusion pressure by 170 +/- 10% (n = 6) of control (100%). Cotinine (2 microg/ml) enhanced this effect at all concentrations of PGE2. Nicotine (2 microg/ml) prevented the effect of PGE2; (2) both cotinine (EC50 470-500 fmol/l) and nicotine (EC50 18-32 pmol/l) activated PLA2 in human placental tissues. These observations indicated that cotinine was more potent than in nicotine activating PLA2 and potentiating the vasoconstrictive effects of PGE2 on fetal placental circulation. Nicotine activates nicotinic receptors and releases placental acetylcholine, a vasodilator of placental arteries. Acetylcholine stimulates muscarinic receptors of endothelial cells resulting in the release of endothelium-derived relaxing factor (EDRF), and possibly nitric oxide. Therefore, nicotine prevents or abolishes the vasoconstrictive effects of PGE2 through the release of EDRF. Cotinine is inactive at nicotinic and muscarinic receptors. Therefore, accumulation of cotinine, the major metabolite of nicotine, in fetal circulation may contribute to production of PGE2 and induction of preterm labor and spontaneous abortions.

  17. Structural models of the membrane anchors of envelope glycoproteins E1 and E2 from pestiviruses

    SciTech Connect

    Wang, Jimin Li, Yue; Modis, Yorgo

    2014-04-15

    The membrane anchors of viral envelope proteins play essential roles in cell entry. Recent crystal structures of the ectodomain of envelope protein E2 from a pestivirus suggest that E2 belongs to a novel structural class of membrane fusion machinery. Based on geometric constraints from the E2 structures, we generated atomic models of the E1 and E2 membrane anchors using computational approaches. The E1 anchor contains two amphipathic perimembrane helices and one transmembrane helix; the E2 anchor contains a short helical hairpin stabilized in the membrane by an arginine residue, similar to flaviviruses. A pair of histidine residues in the E2 ectodomain may participate in pH sensing. The proposed atomic models point to Cys987 in E2 as the site of disulfide bond linkage with E1 to form E1–E2 heterodimers. The membrane anchor models provide structural constraints for the disulfide bonding pattern and overall backbone conformation of the E1 ectodomain. - Highlights: • Structures of pestivirus E2 proteins impose constraints on E1, E2 membrane anchors. • Atomic models of the E1 and E2 membrane anchors were generated in silico. • A “snorkeling” arginine completes the short helical hairpin in the E2 membrane anchor. • Roles in pH sensing and E1–E2 disulfide bond formation are proposed for E1 residues. • Implications for E1 ectodomain structure and disulfide bonding pattern are discussed.

  18. Prostaglandin E2 after septostomy for simple transposition.

    PubMed

    Beattie, Lynne Mary; McLeod, Karen A

    2009-05-01

    In simple transposition of the great arteries (sTGA), balloon atrial septostomy is performed prior to arterial switch to improve mixing of systemic and pulmonary circulations. Following septostomy, some patients are also given prostaglandin E2 (PGE2) until surgical repair. The aims of our study were to identify how often PGE2 is given after septostomy, the indications for starting PGE2, and the effect this has on postoperative outcome. The study was a retrospective review of infants born with sTGA between 2000 and 2005, who underwent arterial switch at Yorkhill Children's Hospital, Glasgow. Over a 5-year period, 26 infants (16 male) with sTGA underwent septostomy. There was a significant rise in mean oxygen saturation following septostomy (mean, 61.4 +/- 11.5% before, 81.5 +/- 9.4% after; p < 0.05). Four of 26 (15%) did not receive PGE2 at all (group 1) and 8 of 26 (30%) received PGE2 before but not after septostomy (group 2). A total of 14 of 26 infants (54%) were given PGE2 following septostomy. This comprised 11 who received PGE2 before and after septostomy (group 3) and 3 who did not receive PGE2 prior to septostomy but did after (group 4). Groups 2 and 3 were compared directly, as they both received PGE2 before septostomy. In group 3, oxygen saturations were lower when PGE2 was started compared with saturations immediately after septostomy (45 +/- 23.6% vs. 80 +/- 10.3%; p < 0.05). Groups 2 and 3 showed no difference in atrial gap after septostomy (9.4 +/- 3 vs. 8 +/- 1 mm; p > 0.05). Fifty percent of infants in group 3 underwent echocardiography prior to restarting PGE2, which revealed a patent arterial duct in all but one patient. Despite PGE2, Group 3 had lower saturations at arterial switch compared with Group 2 (71 +/- 14% vs. 82 +/- 8%; p < 0.05). No difference was observed between group 2 and group 3 with regard to length of cardiopulmonary bypass (group 2, 173 +/- 101.4 min, vs. group 3, 157.9 +/- 42.1 min; p > 0.05). However, the Intensive Care Unit

  19. Ability of the bed bug (Hemiptera: Cimicidae) defensive secretions (E)-2-hexenal and (E)-2-octenal to attract adult bed bugs

    USDA-ARS?s Scientific Manuscript database

    Accurate and timely surveillance of bed bug infestations is critical for development of effective control strategies. While the bed bug produced volatiles (E)-2-hexenal and (E)-2-octenal are considered defensive secretions, through use of EthoVision® video-tracking software we demonstrate that low ...

  20. Inhibition of the entomopathogenic fungus Metarhizium anisopliae in vitro by the bed bug defensive secretions (E)-2-hexenal and (E)-2-octenal

    USDA-ARS?s Scientific Manuscript database

    The two major aldehydes (E)-2-hexenal and (E)-2-octenal emitted as defensive secretions by bed bugs Cimex lectularius L. (Hemiptera: Cimicidae), inhibit the in vitro growth of Metarhizium anisopliae (Metsch.) Sokorin (Hypocreales: Clavicipitaceae). These chemicals inhibit fungal growth by direct con...

  1. Cyclin A/CDK2 binds directly to E2F-1 and inhibits the DNA-binding activity of E2F-1/DP-1 by phosphorylation.

    PubMed

    Xu, M; Sheppard, K A; Peng, C Y; Yee, A S; Piwnica-Worms, H

    1994-12-01

    E2F-1, a member of the E2F transcription factor family, contributes to the regulation of the G1-to-S phase transition in higher eukaryotic cells. E2F-1 forms a heterodimer with DP-1 and binds to several cell cycle regulatory proteins, including the retinoblastoma family (RB, p107, p130) and cyclin A/CDK2 complexes. We have analyzed E2F-1 phosphorylation and its interaction with cyclin A/CDK2 complexes both in vivo and in vitro. In vitro, E2F-1 formed a stable complex with cyclin A/CDK2 but not with either subunit alone. DP-1 did not interact with cyclin A, CDK2, or the cyclin A/CDK2 complex. While the complex of cyclin A/CDK2 was required for stable complex formation with E2F-1, the kinase-active form of CDK2 was not required. However, E2F-1 was phosphorylated by cyclin A/CDK2 in vitro and was phosphorylated in vivo in HeLa cells. Two-dimensional tryptic phosphopeptide mapping studies demonstrated an overlap in the phosphopeptides derived from E2F-1 labeled in vitro and in vivo, indicating that cyclin A/CDK2 may be responsible for the majority of E2F-1 phosphorylation in vivo. Furthermore, an active DNA-binding complex could be reconstituted from purified E2F-1/DP-1 and cyclin A/CDK2. Binding studies conducted both in vitro and in vivo demonstrated that the cyclin A/CDK2-binding region resided within the N-terminal 124 amino acids of E2F-1. Because the stable association of E2F-1 with cyclin A/CDK2 in vitro and in vivo did not require a DP-1- or RB-binding domain and because the interactions could be reconstituted from purified components in vitro, we conclude that the interactions between cyclin A/CDK2 and E2F-1 are direct. Finally, we report that the DNA-binding activity of the E2F-1/DP-1 complex is inhibited following phosphorylation by cyclin A/CDK2.

  2. The E2F transcription factor family regulates CENH3 expression in Arabidopsis thaliana.

    PubMed

    Heckmann, Stefan; Lermontova, Inna; Berckmans, Barbara; De Veylder, Lieven; Bäumlein, Helmut; Schubert, Ingo

    2011-11-01

    To elucidate the epigenetic maintenance mechanism for functional plant centromeres, we studied transcriptional regulation of the centromere-specific histone H3 variant CENH3 in Arabidopsis thaliana. We focused on the structure and activity of the CENH3 promoter (CENH3pro) and its regulation by E2F transcription factors. Use of CENH3pro::GUS reporter gene constructs showed that CENH3pro is active in dividing tissues, and that full expression in root meristems depends on intragenic regulatory elements within the second intron. Chromatin immunoprecipitation identified CENH3 as an E2F target gene. Transient co-expression of a CENH3pro::GUS reporter gene construct with various E2F transcription factors in A. thaliana protoplasts showed that E2Fa and E2Fb (preferentially with dimerization protein DPb) activate CENH3pro. Stable over-expression of E2Fa and E2Fb increased the CENH3 transcript level in planta, whereas over-expression of E2Fc decreased the CENH3 transcript level. Surprisingly, mutation of the two E2F binding sites of CENH3pro, in particular the more upstream one (E2F2), caused an increase in CENH3pro activity, indicating E2F-dependent transcriptional repression. CENH3pro repression may be triggered by the interplay of typical and atypical E2Fs in a cell cycle-dependent manner, and/or by interaction of typical E2Fs with retinoblastoma-related (RBR) protein. We speculate that E2Fs are involved in differential transcriptional regulation of CENH3 versus H3, as H3 promoters lack E2F binding motifs. E2F binding motifs are also present in human and Drosophila CENH3pro regions, thus cell cycle-dependent transcriptional regulation of CENH3 may be highly conserved.

  3. E2 multimeric scaffold for vaccine formulation: immune response by intranasal delivery and transcriptome profile of E2-pulsed dendritic cells.

    PubMed

    Trovato, Maria; Maurano, Francesco; D'Apice, Luciana; Costa, Valerio; Sartorius, Rossella; Cuccaro, Fausta; McBurney, Sean P; Krebs, Shelly J; Prisco, Antonella; Ciccodicola, Alfredo; Rossi, Mauro; Haigwood, Nancy L; De Berardinis, Piergiuseppe

    2016-07-16

    The E2 multimeric scaffold represents a powerful delivery system able to elicit robust humoral and cellular immune responses upon systemic administrations. Here recombinant E2 scaffold displaying the third variable loop of HIV-1 Envelope gp120 glycoprotein was administered via mucosa, and the mucosal and systemic immune responses were analysed. To gain further insights into the molecular mechanisms that orchestrate the immune response upon E2 vaccination, we analysed the transcriptome profile of dendritic cells (DCs) exposed to the E2 scaffold with the aim to define a specific gene expression signature for E2-primed immune responses. The in vivo immunogenicity and the potential of E2 scaffold as a mucosal vaccine candidate were investigated in BALB/c mice vaccinated via the intranasal route. Fecal and systemic antigen-specific IgA antibodies, cytokine-producing CD4(+) and CD8(+) cells were induced assessing the immunogenicity of E2 particles via intranasal administration. The cytokine analysis identified a mixed T-helper cell response, while the systemic antibody response showed a prevalence of IgG1 isotype indicative of a polarized Th2-type immune response. RNA-Sequencing analysis revealed that E2 scaffold up-regulates in DCs transcriptional regulators of the Th2-polarizing cell response, defining a type 2 DC transcriptomic signature. The current study provides experimental evidence to the possible application of E2 scaffold as antigen delivery system for mucosal immunization and taking advantages of genome-wide approach dissects the type of response induced by E2 particles.

  4. Enhanced transcriptional activation by E2 proteins from the oncogenic human papillomaviruses.

    PubMed Central

    Kovelman, R; Bilter, G K; Glezer, E; Tsou, A Y; Barbosa, M S

    1996-01-01

    A systematic comparison of transcriptional activation by papillomavirus E2 proteins revealed that the E2 proteins from high-risk human papillomaviruses (human papillomavirus type 16 [HPV-16] and HPV-18) are much more active than are the E2 proteins from low-risk HPVs (HPV-6b and HPV-11). Despite the tropism of HPVs for particular epithelial cell types, this difference in transcriptional activation was observed in a number of different epithelial and nonepithelial cells. The enhanced activities of the E2 proteins from high-risk HPVs did not result from higher steady-state levels of protein in vivo, and in vitro DNA-binding assays revealed similar binding properties for these two classes of E2 proteins. These results demonstrate that the E2 proteins from high-risk HPVs have an intrinsically enhanced potential to activate transcription from promoters with E2-responsive elements. We found that there are also substantial differences between the activation properties of the bovine papillomavirus type 1 E2 protein and those of either of the two classes of HPV E2 proteins, especially with regard to requirements for particular configurations of E2 binding sites in the target promoter. Our results indicate that there are at least three distinct functional classes of E2 proteins and that these classes of E2 proteins may perform different roles during the respective viral life cycles. PMID:8892874

  5. E2fl1 is a meiosis-specific transcription factor in the protist Tetrahymena thermophila.

    PubMed

    Zhang, Jing; Tian, Miao; Yan, Guan-Xiong; Shodhan, Anura; Miao, Wei

    2017-01-02

    Members of the E2F family of transcription factors have been reported to regulate the expression of genes involved in cell cycle control, DNA replication, and DNA repair in multicellular eukaryotes. Here, E2FL1, a meiosis-specific E2F transcription factor gene, was identified in the model ciliate Tetrahymena thermophila. Loss of this gene resulted in meiotic arrest prior to anaphase I. The cytological experiments revealed that the meiotic homologous pairing was not affected in the absence of E2FL1, but the paired homologous chromosomes did not separate and assumed a peculiar tandem arrangement. This is the first time that an E2F family member has been shown to regulate meiotic events. Moreover, BrdU incorporation showed that DSB processing during meiosis was abnormal upon the deletion of E2FL1. Transcriptome sequencing analysis revealed that E2FL1 knockout decreased the expression of genes involved in DNA replication and DNA repair in T. thermophila, suggesting that the function of E2F is highly conserved in eukaryotes. In addition, E2FL1 deletion inhibited the expression of related homologous chromosome segregation genes in T. thermophila. The result may explain the meiotic arrest phenotype at anaphase I. Finally, by searching for E2F DNA-binding motifs in the entire T. thermophila genome, we identified 714 genes containing at least one E2F DNA-binding motif; of these, 235 downregulated represent putative E2FL1 target genes.

  6. Retention and topology of the bovine viral diarrhea virus glycoprotein E2.

    PubMed

    Radtke, Christina; Tews, Birke Andrea

    2017-10-01

    Pestiviruses are enveloped viruses that bud intracellularly. They have three envelope glycoproteins, E(rns), E1, and E2. E2 is the receptor binding protein and the main target for neutralizing antibodies. Both E(rns) and E2 are retained intracellularly. Here, E2 of the bovine viral diarrhea virus (BVDV) strain CP7 was used to study the membrane topology and intracellular localization of the protein. E2 is localized in the ER and there was no difference between E2 expressed alone or in the context of the viral polyprotein. The mature E2 protein was found to possess a single span transmembrane anchor. For the mapping of a retention signal CD72-E2 fusion proteins, as well as E2 alone were analysed. This confirmed the importance of the transmembrane domain and arginine 355 for intracellular retention, but also revealed a modulating effect on retention through the cytoplasmic tail of the E2 protein, especially through glutamine 370. Mutants with a strong impact on retention were tested in the viral context and we were able to rescue BVDV with certain mutations that in E2 alone impaired intracellular retention and lead to export of E2 to the cells surface.

  7. 26 CFR 1.669(e)-2A - Illustration of the provisions of section 669.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Illustration of the provisions of section 669. 1.669(e)-2A Section 1.669(e)-2A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Taxable Years Beginning Before January 1, 1969 § 1.669(e)-2A Illustration of the provisions of section...

  8. 26 CFR 1.669(e)-2A - Illustration of the provisions of section 669.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 8 2014-04-01 2014-04-01 false Illustration of the provisions of section 669. 1.669(e)-2A Section 1.669(e)-2A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Applicable to Taxable Years Beginning Before January 1, 1969 § 1.669(e)-2A Illustration of the provisions...

  9. 26 CFR 1.669(e)-2A - Illustration of the provisions of section 669.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 8 2012-04-01 2012-04-01 false Illustration of the provisions of section 669. 1.669(e)-2A Section 1.669(e)-2A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Applicable to Taxable Years Beginning Before January 1, 1969 § 1.669(e)-2A Illustration of the provisions...

  10. 26 CFR 1.669(e)-2A - Illustration of the provisions of section 669.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 8 2013-04-01 2013-04-01 false Illustration of the provisions of section 669. 1.669(e)-2A Section 1.669(e)-2A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Applicable to Taxable Years Beginning Before January 1, 1969 § 1.669(e)-2A Illustration of the provisions...

  11. 26 CFR 1.669(e)-2A - Illustration of the provisions of section 669.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 8 2011-04-01 2011-04-01 false Illustration of the provisions of section 669. 1.669(e)-2A Section 1.669(e)-2A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Applicable to Taxable Years Beginning Before January 1, 1969 § 1.669(e)-2A Illustration of the provisions...

  12. Suppression of newborn natural killer cell activity by prostaglandin E2

    SciTech Connect

    Milch, P.O.; Salvatore, W.; Luft, B.; Baker, D.A.

    1988-10-01

    The effect of prostaglandin E2 on natural killer cell activity of cord blood was examined. Natural killer cell activity, determined by chromium 51 release, was significantly reduced after prostaglandin E2 (1 microgram/ml) treatment. Prostaglandin E2 has been found to enhance the cellular spread of herpesvirus. Thus prostaglandins may enhance viral infections indirectly by suppressing natural killer cell activity.

  13. DNA-binding independent cell death from a minimal proapoptotic region of E2F-1.

    PubMed

    Bell, L A; O'Prey, J; Ryan, K M

    2006-09-14

    The ability to induce cell cycle progression while evading cell death is a defining characteristic of cancer. Deregulation of E2F is a common event in most human cancers. Paradoxically, this can lead to both cell cycle progression and apoptosis. Although the way in which E2F causes cell cycle progression is well characterized, the pathways by which E2F induces cell death are less well defined. Many of the known mechanisms through which E2F induces apoptosis occur through regulation of E2F target genes. However, mutants of E2F-1 that lack the transactivation domain are still able to induce cell death. To further investigate this activity, we refined a transactivation independent mutant to identify a minimal apoptotic domain. This revealed that only 75 amino acids from within the DNA-binding domain of E2F-1 is sufficient for cell death and that this activity is also present in the DNA-binding domains of E2F-2 and E2F-3. However, analysis of this domain from E2F-1 revealed it does not bind DNA and is consequently unable to transactivate, repress or de-repress E2F target genes. This provocative observation therefore defines a potential new mechanism of death from E2F and opens up new opportunities for inducing cell death in tumours for therapeutic gain.

  14. E2F7 overexpression leads to tamoxifen resistance in breast cancer cells by competing with E2F1 at miR-15a/16 promoter.

    PubMed

    Chu, Junjun; Zhu, Yinghua; Liu, Yujie; Sun, Lijuan; Lv, Xiaobin; Wu, Yanqin; Hu, Pengnan; Su, Fengxi; Gong, Chang; Song, Erwei; Liu, Bodu; Liu, Qiang

    2015-10-13

    About 50-70% of breast cancers are estrogen receptor α (ERα) positive and most of them are sensitive to endocrine therapy including tamoxifen. However, one third of these patients will eventually develop resistance and relapse. We found that the expression of miR-15a and miR-16 were significantly decreased in tamoxifen resistant ER positive breast cancer cell lines. Exogenous expression of miR-15a/16 mimics re-sensitized resistant cells to tamoxifen by inhibiting Cyclin E1 and B cell lymphoma-2 (Bcl-2) to induce cell growth arrest and apoptosis respectively. Further, we identified that a repressive member of E2F family, E2F7, was responsible for the suppression of miR-15a/16 cluster by competing with E2F1 for E2F binding site at the promoter of their host gene DLEU2. Moreover, high expression of E2F7 is correlated with high risk of relapse and poor prognosis in breast cancer patients receiving tamoxifen treatment. Together, our results suggest that overexpression of E2F7 represses miR-15a/16 and then increases Cyclin E1 and Bcl-2 that result in tamoxifen resistance. E2F7 may be a valuable prognostic marker and a therapeutic target of tamoxifen resistance in breast cancer.

  15. Contribution of the charged residues of hepatitis C virus glycoprotein E2 transmembrane domain to the functions of the E1E2 heterodimer.

    PubMed

    Ciczora, Yann; Callens, Nathalie; Montpellier, Claire; Bartosch, Birke; Cosset, François-Loïc; Op de Beeck, Anne; Dubuisson, Jean

    2005-10-01

    The envelope glycoproteins of Hepatitis C virus (HCV), E1 and E2, form a heterodimer that is retained in the endoplasmic reticulum (ER). The transmembrane (TM) domains play a major role in E1E2 heterodimerization and in ER retention. Two fully conserved charged residues in the middle of the TM domain of E2 (Asp and Arg) are crucial for these functions. Replacement of the Asp residue by a Leu impaired E1E2 heterodimerization, whereas the Arg-to-Leu mutation had a milder effect. Both Asp and Arg residues were shown to contribute to the ER retention function of E2. In addition, the entry function of HCV envelope glycoproteins was affected by these mutations. Together, these data indicate that the charged residues present in the TM domain of E2 play a major role in the biogenesis and the entry function of the E1E2 heterodimer. However, the Asp and Arg residues do not contribute equally to these functions.

  16. High-pressure synthesis of the layered iron oxyselenide BaF e2S e2O with strong magnetic anisotropy

    NASA Astrophysics Data System (ADS)

    Takeiri, Fumitaka; Matsumoto, Yuki; Yamamoto, Takafumi; Hayashi, Naoaki; Li, Zhi; Tohyama, Takami; Tassel, Cédric; Ritter, Clemens; Narumi, Yasuo; Hagiwara, Masayuki; Kageyama, Hiroshi

    2016-11-01

    Using a high-pressure reaction, we successfully synthesized BaF e2S e2O with a uniform stack of [F e2S e2O ] layers. Magnetic susceptibility, heat capacity, Mössbauer spectroscopy, and neutron-diffraction measurements revealed that BaF e2S e2O undergoes antiferromagnetic order at 106 K with a 2-k spin structure where each Fe moment points to a neighboring oxide anion. The same spin structure has been observed in the related iron oxyselenides but with a staggered stack of [F e2C h2O ] (where Ch represents chalcogen) layers (Ch =S ,Se ) . We propose that the strong uniaxial anisotropy inferred from the 2-k structure originates from spin-orbit coupling (SOC) induced by a trans -Fe O2S e4 octahedron, which provides a quasilinear coordination environment as often found in single molecule magnetic complexes. A first-principles calculation with inclusion of SOC supports the stabilization of the 2-k spin structure, giving an unquenched orbital momentum of 0.1 μB/Fe . The present paper provides an idea of how to design magnetic lattices of uniaxial anisotropy using oxychalcogenides and more generally mixed-anion compounds.

  17. dE2F2-independent rescue of proliferation in cells lacking an activator dE2F1.

    PubMed

    Ambrus, Aaron M; Nicolay, Brandon N; Rasheva, Vanya I; Suckling, Richard J; Frolov, Maxim V

    2007-12-01

    In Drosophila melanogaster, the loss of activator de2f1 leads to a severe reduction in cell proliferation and repression of E2F targets. To date, the only known way to rescue the proliferation block in de2f1 mutants was through the inactivation of dE2F2. This suggests that dE2F2 provides a major contribution to the de2f1 mutant phenotype. Here, we report that in mosaic animals, in addition to de2f2, the loss of a DEAD box protein Belle (Bel) also rescues proliferation of de2f1 mutant cells. Surprisingly, the rescue occurs in a dE2F2-independent manner since the loss of Bel does not relieve dE2F2-mediated repression. In the eye disc, bel mutant cells fail to undergo a G1 arrest in the morphogenetic furrow, delay photoreceptor recruitment and differentiation, and show a reduction of the transcription factor Ci155. The down-regulation of Ci155 is important since it is sufficient to partially rescue proliferation of de2f1 mutant cells. Thus, mutation of bel relieves the dE2F2-mediated cell cycle arrest in de2f1 mutant cells through a novel Ci155-dependent mechanism without functional inactivation of the dE2F2 repressor.

  18. Light-Dependent Regulation of DEL1 Is Determined by the Antagonistic Action of E2Fb and E2Fc1[W][OA

    PubMed Central

    Berckmans, Barbara; Lammens, Tim; Van Den Daele, Hilde; Magyar, Zoltan; Bögre, Laszlo; De Veylder, Lieven

    2011-01-01

    Endoreduplication represents a variation on the cell cycle in which multiple rounds of DNA replication occur without subsequent chromosome separation and cytokinesis, thereby increasing the cellular DNA content. It is known that the DNA ploidy level of cells is controlled by external stimuli such as light; however, limited knowledge is available on how environmental signals regulate the endoreduplication cycle at the molecular level. Previously, we had demonstrated that the conversion from a mitotic cell cycle into an endoreduplication cycle is controlled by the atypical E2F transcription factor, DP-E2F-LIKE1 (DEL1), that represses the endocycle onset. Here, the Arabidopsis (Arabidopsis thaliana) DEL1 gene was identified as a transcriptional target of the classical E2Fb and E2Fc transcription factors that antagonistically control its transcript levels through competition for a single E2F cis-acting binding site. In accordance with the reported opposite effects of light on the protein levels of E2Fb and E2Fc, DEL1 transcription depended on the light regime. Strikingly, modified DEL1 expression levels uncoupled the link between light and endoreduplication in hypocotyls, implying that DEL1 acts as a regulatory connection between endocycle control and the photomorphogenic response. PMID:21908689

  19. E2F7 overexpression leads to tamoxifen resistance in breast cancer cells by competing with E2F1 at miR-15a/16 promoter

    PubMed Central

    Chu, Junjun; Zhu, Yinghua; Liu, Yujie; Sun, Lijuan; Lv, Xiaobin; Wu, Yanqin; Hu, Pengnan; Su, Fengxi; Gong, Chang; Song, Erwei; Liu, Bodu; Liu, Qiang

    2015-01-01

    About 50–70% of breast cancers are estrogen receptor α (ERα) positive and most of them are sensitive to endocrine therapy including tamoxifen. However, one third of these patients will eventually develop resistance and relapse. We found that the expression of miR-15a and miR-16 were significantly decreased in tamoxifen resistant ER positive breast cancer cell lines. Exogenous expression of miR-15a/16 mimics re-sensitized resistant cells to tamoxifen by inhibiting Cyclin E1 and B cell lymphoma-2 (Bcl-2) to induce cell growth arrest and apoptosis respectively. Further, we identified that a repressive member of E2F family, E2F7, was responsible for the suppression of miR-15a/16 cluster by competing with E2F1 for E2F binding site at the promoter of their host gene DLEU2. Moreover, high expression of E2F7 is correlated with high risk of relapse and poor prognosis in breast cancer patients receiving tamoxifen treatment. Together, our results suggest that overexpression of E2F7 represses miR-15a/16 and then increases Cyclin E1 and Bcl-2 that result in tamoxifen resistance. E2F7 may be a valuable prognostic marker and a therapeutic target of tamoxifen resistance in breast cancer. PMID:26397135

  20. Molecular functions of the transcription factors E2A and E2-2 in controlling germinal center B cell and plasma cell development

    PubMed Central

    Wöhner, Miriam; Tagoh, Hiromi; Bilic, Ivan; Jaritz, Markus; Poliakova, Daniela Kostanova; Fischer, Maria

    2016-01-01

    E2A is an essential regulator of early B cell development. Here, we have demonstrated that E2A together with E2-2 controlled germinal center (GC) B cell and plasma cell development. As shown by the identification of regulated E2A,E2-2 target genes in activated B cells, these E-proteins directly activated genes with important functions in GC B cells and plasma cells by inducing and maintaining DNase I hypersensitive sites. Through binding to multiple enhancers in the Igh 3′ regulatory region and Aicda locus, E-proteins regulated class switch recombination by inducing both Igh germline transcription and AID expression. By regulating 3′ Igk and Igh enhancers and a distal element at the Prdm1 (Blimp1) locus, E-proteins contributed to Igk, Igh, and Prdm1 activation in plasmablasts. Together, these data identified E2A and E2-2 as central regulators of B cell immunity. PMID:27261530

  1. The banana E2 gene family: Genomic identification, characterization, expression profiling analysis.

    PubMed

    Dong, Chen; Hu, Huigang; Jue, Dengwei; Zhao, Qiufang; Chen, Hongliang; Xie, Jianghui; Jia, Liqiang

    2016-04-01

    The E2 is at the center of a cascade of Ub1 transfers, and it links activation of the Ub1 by E1 to its eventual E3-catalyzed attachment to substrate. Although the genome-wide analysis of this family has been performed in some species, little is known about analysis of E2 genes in banana. In this study, 74 E2 genes of banana were identified and phylogenetically clustered into thirteen subgroups. The predicted banana E2 genes were distributed across all 11 chromosomes at different densities. Additionally, the E2 domain, gene structure and motif compositions were analyzed. The expression of all of the banana E2 genes was analyzed in the root, stem, leaf, flower organs, five stages of fruit development and under abiotic stresses. All of the banana E2 genes, with the exception of few genes in each group, were expressed in at least one of the organs and fruit developments, which indicated that the E2 genes might involve in various aspects of the physiological and developmental processes of the banana. Quantitative RT-PCR (qRT-PCR) analysis identified that 45 E2s under drought and 33 E2s under salt were induced. To the best of our knowledge, this report describes the first genome-wide analysis of the banana E2 gene family, and the results should provide valuable information for understanding the classification, cloning and putative functions of this family.

  2. EWS-FLI1 employs an E2F switch to drive target gene expression

    PubMed Central

    Schwentner, Raphaela; Papamarkou, Theodore; Kauer, Maximilian O.; Stathopoulos, Vassilios; Yang, Fan; Bilke, Sven; Meltzer, Paul S.; Girolami, Mark; Kovar, Heinrich

    2015-01-01

    Cell cycle progression is orchestrated by E2F factors. We previously reported that in ETS-driven cancers of the bone and prostate, activating E2F3 cooperates with ETS on target promoters. The mechanism of target co-regulation remained unknown. Using RNAi and time-resolved chromatin-immunoprecipitation in Ewing sarcoma we report replacement of E2F3/pRB by constitutively expressed repressive E2F4/p130 complexes on target genes upon EWS-FLI1 modulation. Using mathematical modeling we interrogated four alternative explanatory models for the observed EWS-FLI1/E2F3 cooperation based on longitudinal E2F target and regulating transcription factor expression analysis. Bayesian model selection revealed the formation of a synergistic complex between EWS-FLI1 and E2F3 as the by far most likely mechanism explaining the observed kinetics of E2F target induction. Consequently we propose that aberrant cell cycle activation in Ewing sarcoma is due to the de-repression of E2F targets as a consequence of transcriptional induction and physical recruitment of E2F3 by EWS-FLI1 replacing E2F4 on their target promoters. PMID:25712098

  3. Regulation of human genome expression and RNA splicing by human papillomavirus 16 E2 protein.

    PubMed

    Gauson, Elaine J; Windle, Brad; Donaldson, Mary M; Caffarel, Maria M; Dornan, Edward S; Coleman, Nicholas; Herzyk, Pawel; Henderson, Scott C; Wang, Xu; Morgan, Iain M

    2014-11-01

    Human papillomavirus 16 (HPV16) is causative in human cancer. The E2 protein regulates transcription from and replication of the viral genome; the role of E2 in regulating the host genome has been less well studied. We have expressed HPV16 E2 (E2) stably in U2OS cells; these cells tolerate E2 expression well and gene expression analysis identified 74 genes showing differential expression specific to E2. Analysis of published gene expression data sets during cervical cancer progression identified 20 of the genes as being altered in a similar direction as the E2 specific genes. In addition, E2 altered the splicing of many genes implicated in cancer and cell motility. The E2 expressing cells showed no alteration in cell growth but were altered in cell motility, consistent with the E2 induced altered splicing predicted to affect this cellular function. The results present a model system for investigating E2 regulation of the host genome.

  4. EWS-FLI1 employs an E2F switch to drive target gene expression.

    PubMed

    Schwentner, Raphaela; Papamarkou, Theodore; Kauer, Maximilian O; Stathopoulos, Vassilios; Yang, Fan; Bilke, Sven; Meltzer, Paul S; Girolami, Mark; Kovar, Heinrich

    2015-03-11

    Cell cycle progression is orchestrated by E2F factors. We previously reported that in ETS-driven cancers of the bone and prostate, activating E2F3 cooperates with ETS on target promoters. The mechanism of target co-regulation remained unknown. Using RNAi and time-resolved chromatin-immunoprecipitation in Ewing sarcoma we report replacement of E2F3/pRB by constitutively expressed repressive E2F4/p130 complexes on target genes upon EWS-FLI1 modulation. Using mathematical modeling we interrogated four alternative explanatory models for the observed EWS-FLI1/E2F3 cooperation based on longitudinal E2F target and regulating transcription factor expression analysis. Bayesian model selection revealed the formation of a synergistic complex between EWS-FLI1 and E2F3 as the by far most likely mechanism explaining the observed kinetics of E2F target induction. Consequently we propose that aberrant cell cycle activation in Ewing sarcoma is due to the de-repression of E2F targets as a consequence of transcriptional induction and physical recruitment of E2F3 by EWS-FLI1 replacing E2F4 on their target promoters.

  5. The swine CD81 enhances E2-based DNA vaccination against classical swine fever.

    PubMed

    Li, Wenliang; Mao, Li; Zhou, Bin; Liu, Xia; Yang, Leilei; Zhang, Wenwen; Jiang, Jieyuan

    2015-07-09

    Classical swine fever (CSF) is a highly contagious and economically important viral disease that affects the pig industry worldwide. The glycoprotein E2 of CSFV can induce neutralizing antibodies and protective immunity, and is widely used for novel vaccine development. The objective of this study was to explore whether a tetraspanin molecule CD81 could improve the immune responses of an E2-based DNA vaccine. Plasmids pVAX-CD81, pVAX-E2 and pVAX-CD81-E2 were constructed and the expression of target proteins was confirmed in BHK-21 cells by indirect immunofluorescence assay. BALB/c mice were divided into 5 groups and immunized with different plasmids (pVAX-E2, pVAX-CD81-E2, pVAX-E2+pVAX-CD81, pVAX-CD81 and PBS) three times with two weeks interval. The results showed that the introduction of CD81 promoted higher humoral and cellular immune responses than E2 expression alone (P<0.05). In addition, immunization with pVAX-CD81-E2 induced stronger immune responses than pVAX-E2+pVAX-CD81. Furthermore, four groups of pigs were immunized with pVAX-E2, pVAX-CD81-E2, pVAX-CD81 and PBS, respectively. Humoral and cellular immune responses detection showed similar results with those in mice. Compared to pVAX-E2, pVAX-CD81-E2 induced higher titers of neutralizing antibodies after viral challenge and conferred stronger protection. These results confirmed the capacity of swine CD81 enhancing the humoral and cellular responses with an adjuvant effect on CSFV DNA vaccine. This is the first report demonstrating the adjuvant effect of CD81 to enhance the DNA vaccination for swine pathogen.

  6. The evolutionary history of the E2F and DEL genes in Viridiplantae.

    PubMed

    Rauber, Rafael; Cabreira, Caroline; de Freitas, Loreta Brandão; Turchetto-Zolet, Andreia Carina; Margis-Pinheiro, Marcia

    2016-06-01

    The E2 promoter binding factor (E2F) proteins are present in almost all eukaryotic organisms and are essential to control several processes, such as the cell cycle progression, cell division, DNA replication, and apoptosis. The E2F family comprises two different types of proteins: the typical E2Fs and atypical E2Fs, which differ structurally and have specific functions. The E2F gene family was described for the first time in plants in 1999, and since then several studies have focused on the functional aspects, but the evolutionary history of this gene family is still unknown. Here, we investigated the evolutionary history of the E2F gene family in plants. Our findings suggest that E2F proteins arose early after the emergence of the eukaryotic species, while DEL proteins appear to have arisen before the metazoan and plants origin probably through a partial duplication of an ancient E2F protein. Our data also suggest that E2Fs activators and repressors appeared twice during evolution, once in the metazoan lineage and again in the embryophyte lineage.

  7. E2F function in muscle growth is necessary and sufficient for viability in Drosophila

    PubMed Central

    Zappia, Maria Paula; Frolov, Maxim V.

    2016-01-01

    The E2F transcription factor is a key cell cycle regulator. However, the inactivation of the entire E2F family in Drosophila is permissive throughout most of animal development until pupation when lethality occurs. Here we show that E2F function in the adult skeletal muscle is essential for animal viability since providing E2F function in muscles rescues the lethality of the whole-body E2F-deficient animals. Muscle-specific loss of E2F results in a significant reduction in muscle mass and thinner myofibrils. We demonstrate that E2F is dispensable for proliferation of muscle progenitor cells, but is required during late myogenesis to directly control the expression of a set of muscle-specific genes. Interestingly, E2f1 provides a major contribution to the regulation of myogenic function, while E2f2 appears to be less important. These findings identify a key function of E2F in skeletal muscle required for animal viability, and illustrate how the cell cycle regulator is repurposed in post-mitotic cells. PMID:26823289

  8. A functionally distinct member of the DP family of E2F subunits.

    PubMed

    Milton, A; Luoto, K; Ingram, L; Munro, S; Logan, N; Graham, A L; Brummelkamp, T R; Hijmans, E M; Bernards, R; La Thangue, N B

    2006-05-25

    E2F transcription factors regulate genes involved in cell-cycle progression. In mammalian cells, physiological E2F exists as an E2F/DP heterodimer. Currently, eight E2F and two DP subunits have been characterized. We report here the characterization of a new member of the DP family, DP-4. While DP-4 exhibits certain similarities with members of the DP family, it also possesses a number of significant differences. Thus, DP-4 forms a heterodimer with E2F subunits, binds to the E2F site and associates with pocket proteins including pRb. In contrast to DP-1, however, DP-4/E2F-1 complexes exhibit reduced DNA binding activity. Furthermore, DP-4 interferes with E2F-1-dependent transcription and delays cell-cycle progression. These results highlight an emerging complexity in the DP family of E2F subunits, and suggest that DP-4 may endow E2F heterodimers with distinct transcription properties.

  9. Transcriptional regulation of human RANK ligand gene expression by E2F1

    SciTech Connect

    Hu Yan; Sun Meng; Nadiminty, Nagalakshmi; Lou Wei; Pinder, Elaine; Gao, Allen C.

    2008-06-06

    Receptor activator of nuclear factor kappa B ligand (RANKL) is a critical osteoclastogenic factor involved in the regulation of bone resorption, immune function, the development of mammary gland and cardiovascular system. To understand the transcriptional regulation of RANKL, we amplified and characterized a 1890 bp 5'-flanking sequence of human RANKL gene (-1782 bp to +108 bp relative to the transcription start site). Using a series of deletion mutations of the 1890 bp RANKL promoter, we identified a 72 bp region (-172 to -100 bp) mediating RANKL basal transcriptional activity. Sequence analysis revealed a putative E2F binding site within this 72 bp region in the human RANKL promoter. Overexpression of E2F1 increased RANKL promoter activity, while down-regulation of E2F1 expression by small interfering RNA decreased RANKL promoter activity. RT-PCR and enzyme linked immunosorbent assays (ELISA) further demonstrated that E2F1 induced the expression of RANKL. Electrophoretic gel mobility shift assays (EMSA) and antibody competition assays confirmed that E2F1 proteins bind to the consensus E2F binding site in the RANKL promoter. Mutation of the E2F consensus binding site in the RANKL promoter profoundly reduced the basal promoter activity and abolished the transcriptional modulation of RANKL by E2F1. These results suggest that E2F1 plays an important role in regulating RANKL transcription through binding to the E2F consensus binding site.

  10. The Mitotic Checkpoint Gene, SIL is Regulated by E2F1

    PubMed Central

    Erez, Ayelet; Chaussepied, Marie; Tina, Colaizzo-Anas; Aplan, Peter; Ginsberg, Doron; Izraeli, Shai

    2009-01-01

    The SIL gene expression is increased in multiple cancers and correlates with the expression of mitotic spindle checkpoint genes and with increased metastatic potential. SIL regulates mitotic entry, organization of the mitotic spindle and cell survival. The E2F transcription factors regulate cell cycle progression by controlling the expression of genes mediating the G1/S transition. More recently E2F has been shown to regulate mitotic spindle checkpoint genes as well. As SIL expression correlates with mitotic checkpoint genes we hypothesized that SIL is regulated by E2F. We mined raw data of published experiments and performed new experiments by modification of E2F expression in cell lines, reporter assays and chromatin immunoprecipitation. Ectopic expression or endogenous activation of E2F induced the expression of SIL, while knockdown of E2F by shRNA, downregulated SIL expression. E2F activated SIL promoter by reporter assay and bound to SIL promoter in-vivo. Taken together these data demonstrate that SIL is regulated by E2F. As SIL is essential for mitotic entry, E2F may regulate G2/M transition through the induction of SIL. Furthermore, as silencing of SIL cause apoptosis in cancer cells, these finding may have therapeutic relevance in tumors with constitutive activation of E2F. PMID:18649360

  11. E2f8 mediates tumor suppression in postnatal liver development

    PubMed Central

    Kent, Lindsey N.; Rakijas, Jessica B.; Pandit, Shusil K.; Westendorp, Bart; Chen, Hui-Zi; Huntington, Justin T.; Tang, Xing; Bae, Sooin; Srivastava, Arunima; Senapati, Shantibhusan; Martin, Chelsea K.; Cuitino, Maria C.; Perez, Miguel; Clouse, Julian M.; Chokshi, Veda; Shinde, Neelam; Kladney, Raleigh; Sun, Daokun; Perez-Castro, Antonio; Matondo, Ramadhan B.; Nantasanti, Sathidpak; Mokry, Michal; Machiraju, Raghu; Fernandez, Soledad; Rosol, Thomas J.; Pohar, Kamal S.; Pipas, James M.; Schmidt, Carl R.; de Bruin, Alain

    2016-01-01

    E2F-mediated transcriptional repression of cell cycle–dependent gene expression is critical for the control of cellular proliferation, survival, and development. E2F signaling also interacts with transcriptional programs that are downstream of genetic predictors for cancer development, including hepatocellular carcinoma (HCC). Here, we evaluated the function of the atypical repressor genes E2f7 and E2f8 in adult liver physiology. Using several loss-of-function alleles in mice, we determined that combined deletion of E2f7 and E2f8 in hepatocytes leads to HCC. Temporal-specific ablation strategies revealed that E2f8’s tumor suppressor role is critical during the first 2 weeks of life, which correspond to a highly proliferative stage of postnatal liver development. Disruption of E2F8’s DNA binding activity phenocopied the effects of an E2f8 null allele and led to HCC. Finally, a profile of chromatin occupancy and gene expression in young and tumor-bearing mice identified a set of shared targets for E2F7 and E2F8 whose increased expression during early postnatal liver development is associated with HCC progression in mice. Increased expression of E2F8-specific target genes was also observed in human liver biopsies from HCC patients compared to healthy patients. In summary, these studies suggest that E2F8-mediated transcriptional repression is a critical tumor suppressor mechanism during postnatal liver development. PMID:27454291

  12. E2F in vivo binding specificity: Comparison of consensus versus nonconsensus binding sites

    PubMed Central

    Rabinovich, Alina; Jin, Victor X.; Rabinovich, Roman; Xu, Xiaoqin; Farnham, Peggy J.

    2008-01-01

    We have previously shown that most sites bound by E2F family members in vivo do not contain E2F consensus motifs. However, differences between in vivo target sites that contain or lack a consensus E2F motif have not been explored. To understand how E2F binding specificity is achieved in vivo, we have addressed how E2F family members are recruited to core promoter regions that lack a consensus motif and are excluded from other regions that contain a consensus motif. Using chromatin immunoprecipitation coupled with DNA microarray analysis (ChIP-chip) assays, we have shown that the predominant factors specifying whether E2F is recruited to an in vivo binding site are (1) the site must be in a core promoter and (2) the region must be utilized as a promoter in that cell type. We have tested three models for recruitment of E2F to core promoters lacking a consensus site, including (1) indirect recruitment, (2) looping to the core promoter mediated by an E2F bound to a distal motif, and (3) assisted binding of E2F to a site that weakly resembles an E2F motif. To test these models, we developed a new in vivo assay, termed eChIP, which allows analysis of transcription factor binding to isolated fragments. Our findings suggest that in vivo (1) a consensus motif is not sufficient to recruit E2Fs, (2) E2Fs can bind to isolated regions that lack a consensus motif, and (3) binding can require regions other than the best match to the E2F motif. PMID:18836037

  13. Plasmatic regulation of vascular prostacyclin in pregnancy.

    PubMed Central

    Remuzzi, G; Zoja, C; Marchesi, D; Schieppati, A; Mecca, G; Misiani, R; Donati, M B; de Gaetano, G

    1981-01-01

    Activity of prostacyclin-stimulating factor was measured in six normal, non-pregnant women, six women in early normal pregnancy, six in late normal pregnancy, and six in late pregnancy complicated by severe pre-eclampsia. The activity was lower in the women in late pregnancy than in those in early pregnancy and the controls but was about normal in those with severe pre-eclampsia. These results may be relevant to the physiology of pregnancy and the pathogenesis of pre-eclampsia. PMID:6780103

  14. [Influence of zinc administered by total parenteral nutrition on plasmatic zinc levels, on reactive C protein, on serum interleukin-6 and on serum interleukin-6 soluble receptor, in critical patients].

    PubMed

    Menéndez, A M; De Portela, M L; Weisstaub, A; Montemerlo, H; Guidoni, M E; Rusí, F; Zeni, S

    2009-01-01

    To study the interrelationship between serum Interleukin-6 (IL-6), serum Interleukin-6 soluble Receptor (IL-6 sR), C-Reactive Protein (C-RP), plasmatic Zinc levels (PlZn) and their response in relation to Zn administered by TPN, in critical patients. 17 patients, receiving TPN as a consequence of acute pancreatitis (n = 4) or after a major abdominal surgery due to intestinal cancer (n = 7), intestinal fístula (n = 3), intestinal obstruction (n = 2) or intestinal íleus (n = 1) were studied. At the beginning (To) and at the end of the TPN administration (6-21 days) serum IL-6 and IL-6 sR were determined by ELISA; C-RP ultrasensitive (C-RP us) by inmunoturbidimetric method; Zn was determined in TPN and in plasma by Atomic Absorption Spectrometry. Characteristics of the patients were (mean +/- SD and ranges): age: 60.6 +/- 11.7 (37-77) years; BMI (kg/m(2)): 26.0 +/- 3.4 (19.9-34.0). The results (mean +/- standard deviation and ranges) were: Zn provided by TPN (mg/d): 6.1 +/- 2.0 (range 2.8 to 10.8). Biochemical levels were, at To and Tf, respectively: (mean+/-SD and ranges) were at To y Tf, respectively: Zn Pl (microg/dl): 104 +/- 46 (35-177); 120 +/- 55 (52-229); IL-6 (pg/mL) 93 +/- 74 (10-262); 117 +/- 180 (7-761); IL6sR (pg/mL): 1,012 +/- 322 (589-1855); 1,269 +/- 451 (631-2195); C-RP us (mg/L): 71 +/- 63 (2-196); 65 +/- 43 (0-137). There was no correlation between variations of IL6, IL6sR, C-RP, PlZn levels and the daily amount of Zn administered in the TPN mixtures. Two patients presented a bad evolution; they received 4.2 and 5.2 md/d of Zn and showed an increase of IL6 levels, maintained high levels of IL6sR but C-RP levels decreased. the range of 2.8 to 10.8 mg/d of Zn administered in TPN mixtures did not exacerbate the inflammatory response.

  15. Cellular Transformation of Mouse Embryo Fibroblasts in the Absence of Activator E2Fs

    PubMed Central

    Gupta, Tushar; Sáenz Robles, Maria Teresa

    2015-01-01

    ABSTRACT The E2F family of transcription factors, broadly divided into activator and repressor E2Fs, regulates cell cycle genes. Current models indicate that activator E2Fs are necessary for cell cycle progression and tumorigenesis and are also required to mediate transformation induced by DNA tumor viruses. E2Fs are negatively regulated by the retinoblastoma (RB) family of tumor suppressor proteins, and virus-encoded oncogenes disrupt the RB-E2F repressor complexes. This results in the release of activator E2Fs and induction of E2F-dependent genes. In agreement, expression of large tumor T antigens (TAg) encoded by polyomaviruses in mammalian cells results in increased transcriptional levels of E2F target genes. In addition, tumorigenesis induced by transgenic expression of simian virus 40 (SV40) TAg in choroid plexus or intestinal villi requires at least one activator E2F. In contrast, we show that SV40 TAg-induced transformation in mouse embryonic fibroblasts is independent of activator E2Fs. This work, coupled with recent studies showing that proliferation in stem and progenitor cells is independent of activator E2Fs, suggests the presence of parallel pathways governing cell proliferation and tumorigenesis. IMPORTANCE The RB-E2F pathway is altered in many cancers and is also targeted by DNA tumor viruses. Viral oncoprotein action on RBs results in the release of activator E2Fs and upregulation of E2F target genes; thus, activator E2Fs are considered essential for normal and tumorigenic cell proliferation. However, we have observed that SV40 large T antigen can induce cell proliferation and transformation in the absence of activator E2Fs. Our results also suggest that TAg action on pRBs regulates both E2F-dependent and -independent pathways that govern proliferation. Thus, specific cell proliferation pathways affected by RB alterations in cancer may be a factor in tumor behavior and response to therapy. PMID:25717106

  16. Structure of a RING E3 ligase and ubiquitin-loaded E2 primed for catalysis

    PubMed Central

    Plechanovová, Anna; Jaffray, Ellis; Tatham, Michael H.; Naismith, James H.; Hay, Ronald T.

    2012-01-01

    SUMMARY Ubiquitin modification is mediated by a large family of specificity determining ubiquitin E3 ligases. To facilitate ubiquitin transfer, RING E3 ligases bind both substrate and a ubiquitin E2 conjugating enzyme linked to ubiquitin via a thioester bond, but the mechanism of transfer has remained elusive. Here we report the crystal structure of the dimeric RING of RNF4 in complex with E2 (UbcH5a) linked by an isopeptide bond to ubiquitin. While the E2 contacts a single protomer of the RING, ubiquitin is folded back onto the E2 by contacts from both RING protomers. The C-terminal tail of ubiquitin is locked into an active site groove on the E2 by an intricate network of interactions, resulting in changes at the E2 active site. This arrangement is primed for catalysis as it can deprotonate the incoming substrate lysine residue and stabilise the consequent tetrahedral transition state intermediate. PMID:22842904

  17. Structural flexibility at a major conserved antibody target on hepatitis C virus E2 antigen

    PubMed Central

    Kong, Leopold; Lee, David E.; Kadam, Rameshwar U.; Liu, Tong; Giang, Erick; Nieusma, Travis; Garces, Fernando; Tzarum, Netanel; Woods, Virgil L.; Ward, Andrew B.; Li, Sheng; Wilson, Ian A.; Law, Mansun

    2016-01-01

    Hepatitis C virus (HCV) is a major cause of liver disease, affecting over 2% of the world’s population. The HCV envelope glycoproteins E1 and E2 mediate viral entry, with E2 being the main target of neutralizing antibody responses. Structural investigations of E2 have produced templates for vaccine design, including the conserved CD81 receptor-binding site (CD81bs) that is a key target of broadly neutralizing antibodies (bNAbs). Unfortunately, immunization with recombinant E2 and E1E2 rarely elicits sufficient levels of bNAbs for protection. To understand the challenges for eliciting bNAb responses against the CD81bs, we investigated the E2 CD81bs by electron microscopy (EM), hydrogen–deuterium exchange (HDX), molecular dynamics (MD), and calorimetry. By EM, we observed that HCV1, a bNAb recognizing the N-terminal region of the CD81bs, bound a soluble E2 core construct from multiple angles of approach, suggesting components of the CD81bs are flexible. HDX of multiple E2 constructs consistently indicated the entire CD81bs was flexible relative to the rest of the E2 protein, which was further confirmed by MD simulations. However, E2 has a high melting temperature of 84.8 °C, which is more akin to proteins from thermophilic organisms. Thus, recombinant E2 is a highly stable protein overall, but with an exceptionally flexible CD81bs. Such flexibility may promote induction of nonneutralizing antibodies over bNAbs to E2 CD81bs, underscoring the necessity of rigidifying this antigenic region as a target for rational vaccine design. PMID:27791120

  18. Arginine methylation-dependent reader-writer interplay governs growth control by E2F-1.

    PubMed

    Zheng, Shunsheng; Moehlenbrink, Jutta; Lu, Yi-Chien; Zalmas, Lykourgos-Panagiotis; Sagum, Cari A; Carr, Simon; McGouran, Joanna F; Alexander, Leila; Fedorov, Oleg; Munro, Shonagh; Kessler, Benedikt; Bedford, Mark T; Yu, Qiang; La Thangue, Nicholas B

    2013-10-10

    The mechanisms that underlie and dictate the different biological outcomes of E2F-1 activity have yet to be elucidated. We describe the residue-specific methylation of E2F-1 by the asymmetric dimethylating protein arginine methyltransferase 1 (PRMT1) and symmetric dimethylating PRMT5 and relate the marks to different functional consequences of E2F-1 activity. Methylation by PRMT1 hinders methylation by PRMT5, which augments E2F-1-dependent apoptosis, whereas PRMT5-dependent methylation favors proliferation by antagonizing methylation by PRMT1. The ability of E2F-1 to prompt apoptosis in DNA damaged cells coincides with enhanced PRMT1 methylation. In contrast, cyclin A binding to E2F-1 impedes PRMT1 methylation and augments PRMT5 methylation, thus ensuring that E2F-1 is locked into its cell-cycle progression mode. The Tudor domain protein p100-TSN reads the symmetric methylation mark, and binding of p100-TSN downregulates E2F-1 apoptotic activity. Our results define an exquisite level of precision in the reader-writer interplay that governs the biological outcome of E2F-1 activity.

  19. Arginine methylation-dependent reader-writer interplay governs growth control by E2F-1

    PubMed Central

    Zheng, Shunsheng; Moehlenbrink, Jutta; Lu, Yi-Chien; Zalmas, Lykourgos-Panagiotis; Sagum, Cari A.; Carr, Simon; McGouran, Joanna F.; Alexander, Leila; Fedorov, Oleg; Munro, Shonagh; Kessler, Benedikt; Bedford, Mark T.; Yu, Qiang; La Thangue, Nicholas B.

    2014-01-01

    Summary The mechanisms that underlie and dictate the different biological outcomes of E2F-1 activity have yet to be elucidated. We describe the residue-specific methylation of E2F-1 by the asymmetric dimethylating protein arginine methyltransferase (PRMT) 1 and symmetric dimethylating PRMT5, and relate the marks to different functional consequences of E2F-1 activity. Methylation by PRMT1 hinders methylation by PRMT5, which augments E2F-1-dependent apoptosis, whereas PRMT5-dependent methylation favours proliferation by antagonising methylation by PRMT1. The ability of E2F-1 to prompt apoptosis in DNA damaged cells coincides with enhanced PRMT1 methylation. In contrast, cyclin A binding to E2F-1 impedes PRMT1 methylation and augments PRMT5 methylation, thus ensuring that E2F-1 is locked into its cell cycle progression mode. The Tudor domain protein p100-TSN reads the symmetric methylation mark, and binding of p100-TSN down-regulates E2F-1 apoptotic activity. Our results define an exquisite level of precision in the reader-writer interplay that governs the biological outcome of E2F-1 activity. PMID:24076217

  20. Structure and partial genomic sequence of the human E2F1 gene.

    PubMed

    Neuman, E; Sellers, W R; McNeil, J A; Lawrence, J B; Kaelin, W G

    1996-09-16

    The E2F family of transcription factors appears to play a critical role in the transcription of certain genes required for cell cycle progression. E2F1, the first cloned member of this family, is regulated during the cell cycle at the mRNA level by changes in transcription of the E2F1 gene and at the protein level by complex formation with proteins such as the retinoblastoma gene product (pRB), cyclin A and DP1. E2F1 can override a pRB-induced G1/S block and can behave as an oncogene in certain cells. E2F1 was cloned and was found to contain seven exons. The dinucleotides at the 5' and 3' splice sites of intron 4 do not agree with consensus splice site sequences. Fluorescence in situ hybridization localized E2F1 to chromosome 20q11. Knowledge of the organization of E2F1 may facilitate identification of additional E2F family members, as well as detection of E2F1 abnormalities in human tumors.

  1. 14-3-3 proteins integrate E2F activity with the DNA damage response

    PubMed Central

    Milton, Alasdair H; Khaire, Nandkumar; Ingram, Laura; O'donnell, Amanda J; La Thangue, Nicholas B

    2006-01-01

    The E2F family is composed of at least eight E2F and two DP subunits, which in cells exist as E2F/DP heterodimers that bind to and regulate E2F target genes. While DP-1 is an essential and widespread component of E2F, much less is known about the DP-3 subunit, which exists as a number of distinct protein isoforms that differ in several respects including the presence of a nuclear localisation signal (NLS). We show here that the NLS region of DP-3 harbours a binding site for 14-3-3ɛ, and that binding of 14-3-3ɛ alters the cell cycle and apoptotic properties of E2F. DP-3 responds to DNA damage, and the interaction between DP-3 and 14-3-3ɛ is under DNA damage-responsive control. Further, 14-3-3ɛ is present in the promoter region of certain E2F target genes, and reducing 14-3-3ɛ levels induces apoptosis. These results identify a new level of control on E2F activity and, at a more general level, suggest that 14-3-3 proteins integrate E2F activity with the DNA damage response. PMID:16482218

  2. 14-3-3 proteins integrate E2F activity with the DNA damage response.

    PubMed

    Milton, Alasdair H; Khaire, Nandkumar; Ingram, Laura; O'Donnell, Amanda J; La Thangue, Nicholas B

    2006-03-08

    The E2F family is composed of at least eight E2F and two DP subunits, which in cells exist as E2F/DP heterodimers that bind to and regulate E2F target genes. While DP-1 is an essential and widespread component of E2F, much less is known about the DP-3 subunit, which exists as a number of distinct protein isoforms that differ in several respects including the presence of a nuclear localisation signal (NLS). We show here that the NLS region of DP-3 harbours a binding site for 14-3-3epsilon, and that binding of 14-3-3epsilon alters the cell cycle and apoptotic properties of E2F. DP-3 responds to DNA damage, and the interaction between DP-3 and 14-3-3epsilon is under DNA damage-responsive control. Further, 14-3-3epsilon is present in the promoter region of certain E2F target genes, and reducing 14-3-3epsilon levels induces apoptosis. These results identify a new level of control on E2F activity and, at a more general level, suggest that 14-3-3 proteins integrate E2F activity with the DNA damage response.

  3. The B lineage transcription factor E2A regulates apoptosis in chronic lymphocytic leukemia (CLL) cells.

    PubMed

    Kardava, Lela; Yang, Qi; St Leger, Anthony; Foon, Kenneth A; Lentzsch, Suzanne; Vallejo, Abbe N; Milcarek, Christine; Borghesi, Lisa

    2011-06-01

    Chronic lymphocytic leukemia (CLL) is a common malignancy characterized by the accumulation of B lymphocytes with an antigen-experienced activated CD19(+)CD5(+) clonal phenotype. Clinically, ∼50% of cases will behave more aggressively. Here, we investigate the role of the major B-cell transcription factor E2A, a known regulator of B-cell survival and proliferation, to CLL persistence. We show that E2A is elevated at the mRNA and protein levels relative to normal B-cell subsets. E2A silencing in primary CLL cells leads to a significant increase in spontaneous apoptosis in both CD38(+) (aggressive) and CD38(-) (indolent) cases. Moreover, E2A knockdown synergizes with the immunomodulatory drug lenalidomide to reduce CLL viability. E2A is known to restrain the proliferation of primary B and T lymphocytes at multiple stages of maturation and we report that targeted E2A disruption increases the frequency of Ki-67(+) CLL cells in the absence of effects on de novo proliferation. At the molecular level, E2A siRNA-treated CLL cells display reduced expression of key genes associated with survival and cell cycling including p27, p21 and mcl-1, of which the former two are known E2A target genes. Thus, E2A, a key transcription factor associated with the B-cell activation profile, regulates apoptosis in CLL and may contribute to disease pathology.

  4. E2A is a transcriptional regulator of CD38 expression in chronic lymphocytic leukemia.

    PubMed

    Saborit-Villarroya, I; Vaisitti, T; Rossi, D; D'Arena, G; Gaidano, G; Malavasi, F; Deaglio, S

    2011-03-01

    CD38, a nucleotide-metabolizing ectoenzyme and a receptor, is a negative prognostic marker for chronic lymphocytic leukemia (CLL) patients. CD38 has a genetic polymorphism, with a C → G variation in a putative E-box located in a regulatory region. E2A, the predominant E-box factor in B lymphocytes, was found to be highly expressed by CD38(+) CLL patients. The highest CD38 levels scored by E2A(+)/G carrier patients suggested that E2A is (i) directly associated with CD38 expression, and that (ii) the binding of the transcription factor is influenced by the CD38 genotype. Chromatin immunoprecipitation indicated that E2A directly interacts with the CD38 regulatory region. Furthermore, E2A binding was stronger in the presence of the G allele. Experiments of E2A silencing led to a significant reduction of surface levels of CD38, confirming the working hypothesis. A direct functional interplay between E2A and CD38 was shown by exposing CLL cells to interleukin-2 and TLR-9 ligands, both inducers of CD38 expression. Under these conditions, CD38 upregulation was primarily conditioned by the presence of E2A and then by the G allele. The results of this study link E2A and CD38 expression within a common pathway, in which E-protein activity is required for the efficient induction of CD38 transcription.

  5. Characterization of the nuclear localization signal of high risk HPV16 E2 protein

    SciTech Connect

    Klucevsek, Kristin; Wertz, Mary; Lucchi, John; Leszczynski, Anna; Moroianu, Junona . E-mail: moroianu@bc.edu

    2007-03-30

    The E2 protein of high risk human papillomavirus type 16 (HPV16) contains an amino-terminal (N) domain, a hinge (H) region and a carboxyl-terminal (C) DNA-binding domain. Using enhanced green fluorescent protein (EGFP) fusions with full length E2 and E2 domains in transfection assays in HeLa cells, we found that the C domain is responsible for the nuclear localization of E2 in vivo, whereas the N and H domains do not contain additional nuclear localization signals (NLSs). Deletion analysis of EGFP-E2 and EGFP-cE2 determined that the C domain contains an {alpha} helix cNLS that overlaps with the DNA-binding region. Mutational analysis revealed that the arginine and lysine residues in this cNLS are essential for nuclear localization of HPV16 E2. Interestingly, these basic amino acid residues are well conserved among the E2 proteins of BPV-1 and some high risk HPV types but not in the low risk HPV types, suggesting that there are differences between the NLSs and corresponding nuclear import pathways between these E2 proteins.

  6. Polymorphic genetic characterization of E2 gene of bovine viral diarrhea virus in China.

    PubMed

    Lang, Yifei; Gao, Shandian; Du, Junzheng; Shao, Junjun; Cong, Guozheng; Lin, Tong; Zhao, Furong; Liu, Lihong; Chang, Huiyun

    2014-12-05

    Bovine viral diarrhea virus (BVDV) is one of the wide distributed pathogenic viruses of livestock and wild animals worldwide. E2 glycoprotein is a major structural component of the BVDV virion and plays a key role in viral attachment to host cells and inducing immune responses against viral infection. In order to gain detailed information of the E2 coding region of BVDV circulating in China, 46 positive samples were tested by RT-PCR for the E2 coding region. The 1122 nt nucleotide sequences of full-length E2 were harvested and analyzed. The results suggested that full-length E2 was an ideal target for BVDV genotyping and divided the domestic BVDV isolates into 9 subgenotypes, namely BVDV-1a, -1b1, -1c, -1d, -1o, -1m, -1p, -1q and BVDV-2a, showing great diversity. The difference of nonsynonymous and synonymous substitution rates (dN-dS) inferred both positive and purifying selection of the E2. However, combination of positive and purifying selection at different points indicated purifying selection within the complete E2. Protein properties analysis based on glycosylation sites and epitope prediction demonstrated that the biological character of E2 among individual BVDV subgenotype was similar, but may alter due to amino acid changes. For the first time, the comprehensive collection of E2 sequences of Chinese BVDV isolates was elucidated, which would provide information for future vaccine design and BVD control in China.

  7. [Cross-reactivity evaluation of improved estradiol (E2) assay reagent based on chemiluminescent enzyme immunoassay].

    PubMed

    Yamamoto, Kyohei; Kohama, Mika; Nakahara, Fumiko; Yamakami, Asuka; Tanaka, Chie; Momoeda, Mikio; Takeda, Kyoko

    2014-08-01

    We evaluated the performance of a newly-improved estradiol(E2) assay reagent (NEW LP-E2-N), which replaces murine monoclonal antibody in the present reagent (LP-E2-N) with sheep monoclonal antibody, since we had experienced discrepant E2 assay results between LP-E2-N and other commercially available E2 assay kits. Several examinations with the new assay reagent indicated a good performance in terms of the limit of quantity, reproducibility (within-run and between-day), dilution linearity, and influence of blood components except hemoglobin. Using analogues and/or metabolites of E2, low or no cross-reactivity has been shown in NEW LP-E2-N: 0.26% with 25 ng/mL of estrone (El), 0.14% with 100 ng/mL of estradiol-3-sulfate, 0.02% with 200 ng/mL of 17α-ethynylestradiol, and less than 0.001% with 100 ng/mL of estriol(E3), estra-17-glucuronide, and estramustine, respectively. Although discrepant results between NEW LP-E2-N and LP-E2-N were observed in 12 samples, including 9 cases under oral hormone therapy, data from these samples were similar to those using 2 commercially available E2 assay kits, Architect and Eclusys, suggesting that the NEW LP E2-N shows adequate clinical efficacy. A correlation study was performed with LP E2-N, Architect, and Eclusys using 149 serum samples obtained from patients and healthy volunteers, and the correlation results were as follows: r = 0.831, y = 0.98x + 40.6 against LP-E2-N, r = 0.991, y = 1.08x + 12.4 against Architect, r = 0.995, y = 0.80x - 3.7 against Eclusys. In conclusion, the NEW LP-E2-N reagent displayed a relatively favorable kit performance except for in the elevation of assay results with hemoglobin, as well as a low cross-reactivity with E2 analogues and/or metabolites.

  8. E2-25K SUMOylation inhibits proteasome for cell death during cerebral ischemia/reperfusion

    PubMed Central

    Jeong, Eun Il; Chung, Hae Won; Lee, Won Jea; Kim, Seo-Hyun; Kim, Hyunjoo; Choi, Seon-Guk; Jung, Yong-Keun

    2016-01-01

    Cerebral ischemia/reperfusion (I/R) causes brain damage accompanied by ubiquitin accumulation and impairment of proteasome activity. In this study, we report that E2-25K, an E2-conjugating enzyme, is SUMOylated during oxidative stress and regulates cerebral I/R-induced damage. Knockdown of E2-25K expression protects against oxygen/glucose deprivation and reoxygenation (OGD/R)-induced neuronal cell death, whereas ectopic expression of E2-25K stimulates it. Compared with the control mice, cerebral infarction lesions and behavioral/neurological disorders are ameliorated in E2-25K knockout mice during middle cerebral artery occlusion and reperfusion. In particular, E2-25K is SUMOylated at Lys14 under oxidative stress, OGD/R and I/R to prompt cell death. Further, E2-25K downregulates the proteasome subunit S5a to impair proteasome complex and thus restrain proteasome activity under oxidative stress. This proteasome inhibitory activity of E2-25K is dependent on its SUMOylation. These results suggest that E2-25K has a crucial role in oxidative stress and cerebral I/R-induced damage through inhibiting proteasome via its SUMOylation. PMID:28032866

  9. E2F1 transcription factor and its impact on growth factor and cytokine signaling.

    PubMed

    Ertosun, Mustafa Gokhan; Hapil, Fatma Zehra; Osman Nidai, Ozes

    2016-10-01

    E2F1 is a transcription factor involved in cell cycle regulation and apoptosis. The transactivation capacity of E2F1 is regulated by pRb. In its hypophosphorylated form, pRb binds and inactivates DNA binding and transactivating functions of E2F1. The growth factor stimulation of cells leads to activation of CDKs (cyclin dependent kinases), which in turn phosphorylate Rb and hyperphosphorylated Rb is released from E2F1 or E2F1/DP complex, and free E2F1 can induce transcription of several genes involved in cell cycle entry, induction or inhibition of apoptosis. Thus, growth factors and cytokines generally utilize E2F1 to direct cells to either fate. Furthermore, E2F1 regulates expressions of various cytokines and growth factor receptors, establishing positive or negative feedback mechanisms. This review focuses on the relationship between E2F1 transcription factor and cytokines (IL-1, IL-2, IL-3, IL-6, TGF-beta, G-CSF, LIF), growth factors (EGF, KGF, VEGF, IGF, FGF, PDGF, HGF, NGF), and interferons (IFN-α, IFN-β and IFN-γ).

  10. The E2F2 Transcription Factor Sustains Hepatic Glycerophospholipid Homeostasis in Mice

    PubMed Central

    Maldonado, Eduardo N.; Delgado, Igotz; Furland, Natalia E.; Buqué, Xabier; Iglesias, Ainhoa; Aveldaño, Marta I.; Zubiaga, Ana; Fresnedo, Olatz; Ochoa, Begoña

    2014-01-01

    Increasing evidence links metabolic signals to cell proliferation, but the molecular wiring that connects the two core machineries remains largely unknown. E2Fs are master regulators of cellular proliferation. We have recently shown that E2F2 activity facilitates the completion of liver regeneration after partial hepatectomy (PH) by regulating the expression of genes required for S-phase entry. Our study also revealed that E2F2 determines the duration of hepatectomy-induced hepatic steatosis. A transcriptomic analysis of normal adult liver identified “lipid metabolism regulation” as a major E2F2 functional target, suggesting that E2F2 has a role in lipid homeostasis. Here we use wild-type (E2F2+/+) and E2F2 deficient (E2F2−/−) mice to investigate the in vivo role of E2F2 in the composition of liver lipids and fatty acids in two metabolically different contexts: quiescence and 48-h post-PH, when cellular proliferation and anabolic demands are maximal. We show that liver regeneration is accompanied by large triglyceride and protein increases without changes in total phospholipids both in E2F2+/+ and E2F2−/− mice. Remarkably, we found that the phenotype of quiescent liver tissue from E2F2−/− mice resembles the phenotype of proliferating E2F2+/+ liver tissue, characterized by a decreased phosphatidylcholine to phosphatidylethanolamine ratio and a reprogramming of genes involved in generation of choline and ethanolamine derivatives. The diversity of fatty acids in total lipid, triglycerides and phospholipids was essentially preserved on E2F2 loss both in proliferating and non-proliferating liver tissue, although notable exceptions in inflammation-related fatty acids of defined phospholipid classes were detected. Overall, our results indicate that E2F2 activity sustains the hepatic homeostasis of major membrane glycerolipid components while it is dispensable for storage glycerolipid balance. PMID:25396754

  11. E2F1 enhances glycolysis through suppressing Sirt6 transcription in cancer cells.

    PubMed

    Wu, Minghui; Seto, Edward; Zhang, Jingsong

    2015-05-10

    The fast proliferation of cancer cells requires reprogramming of its energy metabolism with aerobic glycolysis as a major energy source. Sirt6, a class III histone deacetylase, has been shown to down regulate glycolysis by inhibiting the expression of several key glycolytic genes. Based on the published study on the metabolic phenotype of E2F1 -/- mice and SIRT6 -/- mice, we hypothesize that E2F1 enhances glycolysis and inhibits the expression of Sirt6. Indeed, over-expressing of E2F1, but not its DNA binding deficient mutant, significantly enhanced glucose uptake and lactate production in bladder and prostate cancer cell lines. E2F1 over-expression also suppressed Sirt6 expression and function. Moreover, E2F1 directly bound to Sirt6 promoter and suppressed Sirt6 promoter activity under both normoxic and hypoxic culture conditions. E2F1 siRNA blocked the up-regulation of E2F1 under hypoxia, increased Sirt6 expression and decreased glycolysis compared to those of scrambled siRNA transected cells. Furthermore, HDAC1 deacetylated E2F1 and diminished its transcription suppression of Sirt6 promoter. Treatment with the HDAC inhibitor, trichostatin A (TSA), suppressed Sirt6 promoter activity with increased binding of acetylated E2F1 to Sirt6 promoter. Mutating the E2F1 binding site on the proximal Sirt6 promoter abolished the suppression of Sirt6 transcription by TSA. These data indicate a novel oncogenic role of E2F1, i.e. enhancing glycolysis by suppressing Sirt6 transcription.

  12. E2F transcription factors and digestive system malignancies: how much do we know?

    PubMed

    Xanthoulis, Athanasios; Tiniakos, Dina G

    2013-06-07

    E2F family of transcription factors regulates various cellular functions related to cell cycle and apoptosis. Its individual members have traditionally been classified into activators and repressors, based on in vitro studies. However their contribution in human cancer is more complicated and difficult to predict. We review current knowledge on the expression of E2Fs in digestive system malignancies and its clinical implications for patient prognosis and treatment. E2F1, the most extensively studied member and the only one with prognostic value, exhibits a tumor-suppressing activity in esophageal, gastric and colorectal adenocarcinoma, and in hepatocellular carcinoma (HCC), whereas in pancreatic ductal adenocarcinoma and esophageal squamous cell carcinoma may function as a tumor-promoter. In the latter malignancies, E2F1 immunohistochemical expression has been correlated with higher tumor grade and worse patient survival, whereas in esophageal, gastric and colorectal adenocarcinomas is a marker of increased patient survival. E2F2 has only been studied in colorectal cancer, where its role is not considered significant. E2F4's role in colorectal, gastric and hepatic carcinogenesis is tumor-promoting. E2F8 is strongly upregulated in human HCC, thus possibly contributing to hepatocarcinogenesis. Adenoviral transfer of E2F as gene therapy to sensitize pancreatic cancer cells for chemotherapeutic agents has been used in experimental studies. Other therapeutic strategies are yet to be developed, but it appears that targeted approaches using E2F-agonists or antagonists should take into account the tissue-dependent function of each E2F member. Further understanding of E2Fs' contribution in cellular functions in vivo would help clarify their role in carcinogenesis.

  13. E2 conjugating enzyme selectivity and requirements for function of the E3 ubiquitin ligase CHIP.

    PubMed

    Soss, Sarah E; Yue, Yuanyuan; Dhe-Paganon, Sirano; Chazin, Walter J

    2011-06-17

    The transfer of ubiquitin (Ub) to a substrate protein requires a cascade of E1 activating, E2 conjugating, and E3 ligating enzymes. E3 Ub ligases containing U-box and RING domains bind both E2∼Ub conjugates and substrates to facilitate transfer of the Ub molecule. Although the overall mode of action of E3 ligases is well established, many of the mechanistic details that determine the outcome of ubiquitination are poorly understood. CHIP (carboxyl terminus of Hsc70-interacting protein) is a U-box E3 ligase that serves as a co-chaperone to heat shock proteins and is critical for the regulation of unfolded proteins in the cytosol. We have performed a systematic analysis of the interactions of CHIP with E2 conjugating enzymes and found that only a subset bind and function. Moreover, some E2 enzymes function in pairs to create products that neither create individually. Characterization of the products of these reactions showed that different E2 enzymes produce different ubiquitination products, i.e. that E2 determines the outcome of Ub transfer. Site-directed mutagenesis on the E2 enzymes Ube2D1 and Ube2L3 (UbcH5a and UbcH7) established that an SPA motif in loop 7 of E2 is required for binding to CHIP but is not sufficient for activation of the E2∼Ub conjugate and consequent ubiquitination activity. These data support the proposal that the E2 SPA motif provides specificity for binding to CHIP, whereas activation of the E2∼Ub conjugate is derived from other molecular determinants.

  14. Developing a Biosensor for Estrogens in Water Samples: Study ofthe Real-time Response of Live Cells of the Estrogen-sensitive YeastStrain RMY/ER-ERE using Fluorescence Microscopy

    SciTech Connect

    Wozei, E.; Hermanowicz, S.W.; Holman, H-Y.N.

    2005-07-13

    Using a fluorescein di-{beta}-D-galactopyranoside (FDG) substrate we show that in live cells of an estrogen-sensitive yeast strain RMY/ER-ERE with human estrogen receptor (ER{alpha}) gene and the lacZ gene which encodes {beta}-galactosidase, the uptake of 17 {beta}-estradiol (E2) and the subsequent production of {beta}-galactosidase enzyme occur quite rapidly, with maximal enzyme-catalyzed product formation evident after about 30 minutes of exposure to E2. This finding which agrees with the well-known rates of enzyme-catalyzed reactions could have implications for shortening the duration of environmental sample screening and monitoring regimes using yeast-based estrogen assays, and the development of biosensors for environmental estrogens to complement quantification methods.

  15. Developing a Biosensor for Estrogens in Water Samples: Study ofthe Real-time Response of Live Cells of the Estrogen-sensitive YeastStrain RMY/ER-ERE using Fluorescence Microscopy

    SciTech Connect

    Wozei, E.; Hermanowicz, S.W.; Holman, H-Y.N.

    2006-01-01

    Using a fluorescein di-{beta}-d-galactopyranoside (FDG) substrate we show that in live cells of an estrogen-sensitive yeast strain RMY/ER-ERE with human estrogen receptor (ER{alpha}) gene and the lacZ gene which encodes {beta}-galactosidase, the uptake of 17{beta}-estradiol (E2) and the subsequent production of {beta}-galactosidase enzyme occur quite rapidly, with maximal enzyme-catalyzed product formation evident after about 30 min of exposure to E2. This finding which agrees with the well-known rates of enzyme-catalyzed reactions could have implications for shortening the duration of environmental sample screening and monitoring regimes using yeast-based estrogen assays, and the development of biosensors for environmental estrogens to complement quantification methods.

  16. Draft genome sequence of Lactobacillus plantarum strains E2C2 and E2C5 isolated from human stool culture.

    PubMed

    Suryavanshi, Mangesh V; Paul, Dhiraj; Doijad, Swapnil P; Bhute, Shrikant S; Hingamire, Tejashri B; Gune, Rahul P; Shouche, Yogesh S

    2017-01-01

    Probiotic Lactobacillus species offer various health benefits, thus have been employed in treatment and prevention of various diseases. Due to the differences in the isolation source and the site of action, most of the lactobacilli tested in-vitro for probiotics properties fail to extend similar effects in-vivo. Consequently, the search of autochthonous, efficacious and probably population specific probiotics is a high priority in the probiotics research. In this regards, whole genome sequencing of as many Lactobacillus as possible will help to deepen our understanding of biology and their health effects. Here, we provide the genomic insights of two coherent oxalic acid tolerant Lactobacillus species (E2C2 and E2C5) isolated from two different healthy human gut flora. These two isolates were found to have higher tolerance towards oxalic acid (300 mM sodium oxalate). The draft genome of strain E2C2 consists of 3,603,563 bp with 3289 protein-coding genes, 94 RNA genes, and 43.99% GC content, while E2C5 contained 3,615,168 bp, 3293 coding genes (93.4% of the total genes), 95 RNA genes and 43.97% GC content. Based on 16S rRNA gene sequence analysis followed by in silico DNA-DNA hybridization studies, both the strains were identified as Lactobacillus plantarum belonging to family Lactobacillaceae within the phylum Firmicutes. Both the strains were genomically identical, sharing 99.99% CDS that showed 112 SNPs. Both the strains also exhibited deconjugation activity for the bile salts while genome analysis revealed that the L. plantarum strains E2C2 and E2C5 also have the ability to produce vitamins, biotin, alpha- and beta- glucosidase suggesting potential probiotic activities of the isolates. The description presented here is based on the draft genomes of strains E2C2 and E2C5 which are submitted to GenBank under the accession numbers LSST00000000.1 and LTCD00000000.1, respectively.

  17. Structural analysis and evolution of specificity of the SUMO UFD E1-E2 interactions.

    PubMed

    Liu, Bing; Lois, L Maria; Reverter, David

    2017-02-06

    SUMO belongs to the ubiquitin-like family (UbL) of protein modifiers. SUMO is conserved among eukaryotes and is essential for the regulation of processes such as DNA damage repair, transcription, DNA replication and mitosis. UbL modification of proteins occurs via a specific enzymatic cascade formed by the crosstalk between the E1-activating enzyme, the E2-conjugating enzyme and the E3-ligase. An essential discrimination step in all UbL modifiers corresponds to the interaction between E1 and E2 enzymes, which is mediated by the recruitment of the E2 to the UFD domain (Ubiquitin-Fold Domain) of the E1 enzyme. To gain insights in the properties of this interface, we have compared the structures of the complexes between E1 UFD domain and E2 in human and yeast, revealing two alternative UFD platforms that interact with a conserved E2. Comparative sequence analysis of the E1 UFD domain indicates that the E2 binding region has been conserved across phylogenetic closely related species, in which higher sequence conservation can be found in the E2 binding region than in the entire UFD domain. These distinctive strategies for E1-E2 interactions through the UFD domain might be the consequence of a high selective pressure to ensure specificity of each modifier conjugation system.

  18. US NDC Modernization Iteration E2 Prototyping Report: OSD & PC Software Infrastructure

    SciTech Connect

    Prescott, Ryan; Marger, Bernard L.; Chiu, Ailsa

    2014-12-01

    During the second iteration of the US NDC Modernization Elaboration phase (E2), the SNL US NDC Modernization project team completed follow-on COTS surveys & exploratory prototyping related to the Object Storage & Distribution (OSD) mechanism, and the processing control software infrastructure. This report summarizes the E2 prototyping work.

  19. Cell cycle-related transformation of the E2F4-p130 repressor complex

    SciTech Connect

    Popov, Boris . E-mail: popov_478@hotmail.com; Chang, L.-S.; Serikov, Vladimir

    2005-10-28

    During G0 phase the p130, member of the pRb tumor suppressor protein family, forms a repressor complex with E2F4 which is inactivated in G1/S by hyperphosphorylation of the p130. The role of p130 after G1/S remains poorly investigated. We found that in nuclear extracts of T98G cells, the p130-E2F4-DNA (pp-E2F4) complex does not dissociate at G1/S transition, but instead reverts to the p130-E2F4-cyclin E/A-cdk2 (cyc/cdk-pp-E2F4) complex, which is detected in S and G2/M phases of the cell cycle. Hyperphosphorylation of the p130 at G1/S transition is associated with a decrease of its total amount; however, this protein is still detected during the rest of the cell cycle, and it is increasingly hyperphosphorylated in the cytosol, but continuously dephosphorylated in the nucleus. Both nuclear and cytosol cell fractions in T98G cells contain a hyperphosphorylated form of p130 in complex with E2F4 at S and G2/M cell cycle phases. In contrast to T98G cells, transformation of the p130 containing cyc/cdk-pp-E2F4 complex into the p130-pp-E2F4 repressor does not occur in HeLa cells under growth restriction conditions.

  20. Insights into the mechanism of human papillomavirus E2-induced procaspase-8 activation and cell death

    NASA Astrophysics Data System (ADS)

    Singh, Nitu; Senapati, Sanjib; Bose, Kakoli

    2016-02-01

    High-risk human papillomavirus (HR-HPV) E2 protein, the master regulator of viral life cycle, induces apoptosis of host cell that is independent of its virus-associated regulatory functions. E2 protein of HR-HPV18 has been found to be involved in novel FADD-independent activation of caspase-8, however, the molecular basis of this unique non-death-fold E2-mediated apoptosis is poorly understood. Here, with an interdisciplinary approach that involves in silico, mutational, biochemical and biophysical probes, we dissected and characterized the E2-procasapse-8 binding interface. Our data demonstrate direct non-homotypic interaction of HPV18 E2 transactivation domain (TAD) with α2/α5 helices of procaspase-8 death effector domain-B (DED-B). The observed interaction mimics the homotypic DED-DED complexes, wherein the conserved hydrophobic motif of procaspase-8 DED-B (F122/L123) occupies a groove between α2/α3 helices of E2 TAD. This interaction possibly drives DED oligomerization leading to caspase-8 activation and subsequent cell death. Furthermore, our data establish a model for E2-induced apoptosis in HR-HPV types and provide important clues for designing E2 analogs that might modulate procaspase-8 activation and hence apoptosis.

  1. NRIP enhances HPV gene expression via interaction with either GR or E2.

    PubMed

    Chang, Szu-Wei; Lu, Pei-Yu; Guo, Jih-Huong; Tsai, Tzung-Chieh; Tsao, Yeou-Ping; Chen, Show-Li

    2012-02-05

    We previously identified a gene, nuclear receptor-interaction protein (NRIP), which functions as a transcription cofactor in glucocorticoid receptor (GR) and human papillomavirus E2 (HPV E2)-driven gene expression. Here, we comprehensively evaluated the role of NRIP in HPV-16 gene expression. NRIP acts as a transcription cofactor to enhance GR-regulated HPV-16 gene expression in the presence of hormone. NRIP also can form complex with E2 that caused NRIP-induced HPV gene expression via E2-binding sites in a hormone-independent manner. Furthermore, NRIP can associate with GR and E2 to form tri-protein complex to activate HPV gene expression via GRE, not the E2-binding site, in a hormone-dependent manner. These results indicate that NRIP and GR are viral E2-binding proteins and that NRIP regulates HPV gene expression via GRE and/or E2 binding site in the HPV promoter in a hormone-dependent or independent manner, respectively.

  2. Functional Characterization of Intracellular and Secreted Forms of a Truncated Hepatitis C Virus E2 Glycoprotein†

    PubMed Central

    Flint, Mike; Dubuisson, Jean; Maidens, Catherine; Harrop, Richard; Guile, Geoffrey R.; Borrow, Persephone; McKeating, Jane A.

    2000-01-01

    The E2 protein of hepatitis C virus (HCV) is believed to be a virion surface glycoprotein that is a candidate for inclusion in an antiviral vaccine. A truncated soluble version of E2 has recently been shown to interact with CD81, suggesting that this protein may be a component of the receptor for HCV. When expressed in eukaryotic cells, a significant proportion of E2 forms misfolded aggregates. To analyze the specificity of interaction between E2 and CD81, the aggregated and monomeric forms of a truncated E2 glycoprotein (E2661) were separated by high-pressure liquid chromatography and analyzed for CD81 binding. Nonaggregated forms of E2 preferentially bound CD81 and a number of conformation-dependent monoclonal antibodies (MAbs). Furthermore, intracellular forms of E2661 were found to bind CD81 with greater affinity than the extracellular forms. Intracellular and secreted forms of E2661 were also found to differ in reactivity with MAbs and human sera, consistent with differences in antigenicity. Together, these data indicate that proper folding of E2 is important for its interaction with CD81 and that modifications of glycans can modulate this interaction. Identification of the biologically active forms of E2 will assist in the future design of vaccines to protect against HCV infection. PMID:10623732

  3. Multimodal regulation of E2F1 gene expression by progestins.

    PubMed

    Wade, Hilary E; Kobayashi, Sakiko; Eaton, Matthew L; Jansen, Michelle S; Lobenhofer, Edward K; Lupien, Mathieu; Geistlinger, Timothy R; Zhu, Wencheng; Nevins, Joseph R; Brown, Myles; Otteson, Deborah C; McDonnell, Donald P

    2010-04-01

    An analysis of mRNA expression in T47D breast cancer cells treated with the synthetic progestin R5020 revealed a subset of progesterone receptor (PR) target genes that are enriched for E2F binding sites. Following up on this observation, we determined that PR-B acts in both direct and indirect manners to positively upregulate E2F1 expression in T47D cells. The direct effects of PR on E2F1 expression were confirmed by chromatin immunoprecipitation (ChIP) analysis, which indicated that the agonist-bound receptor was recruited to several enhancer elements proximal to the E2F1 transcript. However, we also noted that cycloheximide partially inhibits R5020 induction of E2F1 expression, indicating that the ligand-dependent actions of PR on this gene may involve additional indirect regulatory pathways. In support of this hypothesis, we demonstrated that treatment with R5020 significantly increases both hyperphosphorylation of Rb and recruitment of E2F1 to its own promoter, thus activating a positive feedback loop that further amplifies its transcription. Furthermore, we established that PR-mediated induction of Krüppel-like factor 15 (KLF15), which can bind to GC-rich DNA within the E2F1 promoter, is required for maximal induction of E2F1 expression by progestins. Taken together, these results suggest a new paradigm for multimodal regulation of target gene expression by PR.

  4. NRIP enhances HPV gene expression via interaction with either GR or E2

    SciTech Connect

    Chang, Szu-Wei; Lu, Pei-Yu; Guo, Jih-Huong; Tsai, Tzung-Chieh; Tsao, Yeou-Ping; Chen, Show-Li

    2012-02-05

    We previously identified a gene, nuclear receptor-interaction protein (NRIP), which functions as a transcription cofactor in glucocorticoid receptor (GR) and human papillomavirus E2 (HPV E2)-driven gene expression. Here, we comprehensively evaluated the role of NRIP in HPV-16 gene expression. NRIP acts as a transcription cofactor to enhance GR-regulated HPV-16 gene expression in the presence of hormone. NRIP also can form complex with E2 that caused NRIP-induced HPV gene expression via E2-binding sites in a hormone-independent manner. Furthermore, NRIP can associate with GR and E2 to form tri-protein complex to activate HPV gene expression via GRE, not the E2-binding site, in a hormone-dependent manner. These results indicate that NRIP and GR are viral E2-binding proteins and that NRIP regulates HPV gene expression via GRE and/or E2 binding site in the HPV promoter in a hormone-dependent or independent manner, respectively.

  5. Rb inactivation leads to E2F1-mediated DNA double-strand break accumulation.

    PubMed

    Pickering, M T; Kowalik, T F

    2006-02-02

    Although it is unclear which cellular factor(s) is responsible for the genetic instability associated with initiating and sustaining cell transformation, it is known that many cancers have mutations that inactivate the Rb-mediated proliferation pathway. We show here that pRb inactivation and the resultant deregulation of one E2F family member, E2F1, leads to DNA double-strand break (DSB) accumulation in normal diploid human cells. These DSBs occur independent of Atm, p53, caspases, reactive oxygen species, and apoptosis. Moreover, E2F1 does not contribute to c-Myc-associated DSBs, indicating that the DSBs associated with these oncoproteins arise through distinct pathways. We also find E2F1-associated DSBs in an Rb mutated cancer cell line in the absence of an exogenous DSB stimulus. These basal, E2F1-associated DSBs are not observed in a p16(ink4a) inactivated cancer cell line that retains functional pRb, unless pRb is depleted. Thus, Rb status is key to regulating both the proliferation promoting functions associated with E2F and for preventing DNA damage accumulation if E2F1 becomes deregulated. Taken together, these data suggest that loss of Rb creates strong selective pressure, via DSB accumulation, for inactivating p53 mutations and that E2F1 contributes to the genetic instability associated with transformation and tumorigenesis.

  6. 17 CFR 270.6e-2 - Exemptions for certain variable life insurance separate accounts.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... variable life insurance separate accounts. 270.6e-2 Section 270.6e-2 Commodity and Securities Exchanges...-2 Exemptions for certain variable life insurance separate accounts. (a) A separate account, and the... a life insurance company pursuant to the insurance laws or code of (i) any state or territory of...

  7. Structural analysis and evolution of specificity of the SUMO UFD E1-E2 interactions

    PubMed Central

    Liu, Bing; Lois, L. Maria; Reverter, David

    2017-01-01

    SUMO belongs to the ubiquitin-like family (UbL) of protein modifiers. SUMO is conserved among eukaryotes and is essential for the regulation of processes such as DNA damage repair, transcription, DNA replication and mitosis. UbL modification of proteins occurs via a specific enzymatic cascade formed by the crosstalk between the E1-activating enzyme, the E2-conjugating enzyme and the E3-ligase. An essential discrimination step in all UbL modifiers corresponds to the interaction between E1 and E2 enzymes, which is mediated by the recruitment of the E2 to the UFD domain (Ubiquitin-Fold Domain) of the E1 enzyme. To gain insights in the properties of this interface, we have compared the structures of the complexes between E1 UFD domain and E2 in human and yeast, revealing two alternative UFD platforms that interact with a conserved E2. Comparative sequence analysis of the E1 UFD domain indicates that the E2 binding region has been conserved across phylogenetic closely related species, in which higher sequence conservation can be found in the E2 binding region than in the entire UFD domain. These distinctive strategies for E1-E2 interactions through the UFD domain might be the consequence of a high selective pressure to ensure specificity of each modifier conjugation system. PMID:28165030

  8. Insights into the mechanism of human papillomavirus E2-induced procaspase-8 activation and cell death

    PubMed Central

    Singh, Nitu; Senapati, Sanjib; Bose, Kakoli

    2016-01-01

    High-risk human papillomavirus (HR-HPV) E2 protein, the master regulator of viral life cycle, induces apoptosis of host cell that is independent of its virus-associated regulatory functions. E2 protein of HR-HPV18 has been found to be involved in novel FADD-independent activation of caspase-8, however, the molecular basis of this unique non-death-fold E2-mediated apoptosis is poorly understood. Here, with an interdisciplinary approach that involves in silico, mutational, biochemical and biophysical probes, we dissected and characterized the E2-procasapse-8 binding interface. Our data demonstrate direct non-homotypic interaction of HPV18 E2 transactivation domain (TAD) with α2/α5 helices of procaspase-8 death effector domain-B (DED-B). The observed interaction mimics the homotypic DED-DED complexes, wherein the conserved hydrophobic motif of procaspase-8 DED-B (F122/L123) occupies a groove between α2/α3 helices of E2 TAD. This interaction possibly drives DED oligomerization leading to caspase-8 activation and subsequent cell death. Furthermore, our data establish a model for E2-induced apoptosis in HR-HPV types and provide important clues for designing E2 analogs that might modulate procaspase-8 activation and hence apoptosis. PMID:26906543

  9. Retinoblastoma protein (RB) interacts with E2F3 to control terminal differentiation of Sertoli cells.

    PubMed

    Rotgers, E; Rivero-Müller, A; Nurmio, M; Parvinen, M; Guillou, F; Huhtaniemi, I; Kotaja, N; Bourguiba-Hachemi, S; Toppari, J

    2014-06-05

    The retinoblastoma protein (RB) is essential for normal cell cycle control. RB function depends, at least in part, on interactions with the E2F family of DNA-binding transcription factors (E2Fs). To study the role of RB in the adult testis, a Sertoli cell (SC)-specific Rb knockout mouse line (SC-RbKO) was generated using the Cre/loxP recombination system. SC-RbKO mice exhibited an age-dependent testicular atrophy, impaired fertility, severe SC dysfunction, and spermatogenic defects. Removal of Rb in SC induced aberrant SC cycling, dedifferentiation, and apoptosis. Here we show that E2F3 is the only E2F expressed in mouse SCs and that RB interacts with E2F3 during mouse testicular development. In the absence of RB, the other retinoblastoma family members p107 and p130 began interacting with E2F3 in the adult testes. In vivo silencing of E2F3 partially restored the SC maturation and survival as well as spermatogenesis in the SC-RbKO mice. These results point to RB as a key regulator of SC function in adult mice and that the RB/E2F3 pathway directs SC maturation, cell cycle quiescence, and RB protects SC from apoptosis.

  10. E2F and GATA switches turn off WD repeat domain 77 expression in differentiating cells

    PubMed Central

    Yu, Min; Wang, Ulrica; Wang, Zhengxin

    2017-01-01

    WD repeat domain 77 (WDR77) is expressed during earlier lung development when cells are rapidly proliferating and absent in adult lung. It is re-activated during lung tumorigenesis and is essential for lung cancer cell proliferation. Signaling pathways/molecules that control WDR77 gene expression are unknown. Promoter mapping, gel shift assay, and chromatin immunoprecipitation revealed that the WDR77 promoter contains bona fide response elements for E2F and GATA transcriptional factors as demonstrated in prostate cancer, lung cancer and erythroid cells as well as in mouse lung tissues. The WDR77 promoter is transactivated by E2F1, E2F3, GATA2, and GATA6 but suppressed by E2F6, GATA1 and GATA3 in prostate cancer PC3 cells. WDR77 expression is associated with the E2F1, E2F3, GATA2, and GATA6 occupancy on the WDR77 gene and while in contrast the E2F6, GATA2, and GATA3 occupancy is associated with the loss of WDR77 expression during the erythroid maturation and lung development. More importantly, the loss of WDR77 expression that resulted from E2F and GATA switches is required for cellular differentiation of erythroid and lung epithelial cells. In contrast, lung cancer cells avoid post-mitotic differentiation by sustaining WDR77 expression. Altogether, this work provides a novel molecular mechanism by which WDR77 is regulated during erythroid and lung development and lung tumorigenesis. PMID:27274086

  11. Functional characterization of the Sindbis virus E2 glycoprotein by transposon linker-insertion mutagenesis

    SciTech Connect

    Navaratnarajah, Chanakha K.; Kuhn, Richard J. . E-mail: kuhnr@purdue.edu

    2007-06-20

    The glycoprotein envelope of alphaviruses consists of two proteins, E1 and E2. E1 is responsible for fusion and E2 is responsible for receptor binding. An atomic structure is available for E1, but one for E2 has not been reported. In this study, transposon linker-insertion mutagenesis was used to probe the function of different domains of E2. A library of mutants, containing 19 amino acid insertions in the E2 glycoprotein sequence of the prototype alphavirus, Sindbis virus (SINV), was generated. Fifty-seven independent E2 insertions were characterized, of which more than half (67%) gave rise to viable virus. The wild-type-like mutants identify regions that accommodate insertions without perturbing virus production and can be used to insert targeting moieties to direct SINV to specific receptors. The defective and lethal mutants give insight into regions of E2 important for protein stability, transport to the cell membrane, E1-E2 contacts, and receptor binding.

  12. 17 CFR 270.6e-2 - Exemptions for certain variable life insurance separate accounts.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... variable life insurance separate accounts. 270.6e-2 Section 270.6e-2 Commodity and Securities Exchanges...-2 Exemptions for certain variable life insurance separate accounts. (a) A separate account, and the... are derived solely from the sale of variable life insurance contracts as defined in paragraph (c)(1...

  13. 17 CFR 270.6e-2 - Exemptions for certain variable life insurance separate accounts.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... variable life insurance separate accounts. 270.6e-2 Section 270.6e-2 Commodity and Securities Exchanges...-2 Exemptions for certain variable life insurance separate accounts. (a) A separate account, and the... are derived solely from the sale of variable life insurance contracts as defined in paragraph (c)(1...

  14. 17 CFR 270.6e-2 - Exemptions for certain variable life insurance separate accounts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... variable life insurance separate accounts. 270.6e-2 Section 270.6e-2 Commodity and Securities Exchanges...-2 Exemptions for certain variable life insurance separate accounts. (a) A separate account, and the... are derived solely from the sale of variable life insurance contracts as defined in paragraph (c)(1...

  15. E2F-1 gene therapy induces apoptosis and increases chemosensitivity in human pancreatic carcinoma cells.

    PubMed

    Elliott, Mary Jane; Farmer, Michael R; Atienza, Cesar; Stilwell, Ariel; Dong, Yan Bin; Yang, Hai Liang; Wong, Sandra L; McMasters, Kelly M

    2002-01-01

    Pancreatic cancer is often resistant to conventional chemotherapy. In this study, we examined the role of adenovirus-mediated overexpression of E2F-1 in inducing apoptosis and increasing the sensitivity of pancreatic cancer cells to chemotherapeutic agents. MIA PaCa-2 pancreatic head exocrine adenocarcinoma cells (mutant p53) were treated by mock infection or adenoviruses expressing beta-galactosidase or E2F-1 (Ad-E2F-1) alone or in combination with sublethal concentrations of each chemotherapeutic drug. Cell growth and viability were assessed at selected time points. Apoptosis was evaluated by flow cytometry, characteristic changes in cell morphology and poly (ADP-ribose) polymerase (PARP) cleavage. Western blot analysis was used to examine the expression of E2F-1 and Bcl-2 family member proteins and PARP cleavage. Western blot analysis revealed marked overexpression of E2F-1 at a multiplicity of infection (MOI) of 20 and 70. By 3 days after infection, Ad-E2F-1 treatment at an MOI of 70 resulted in approximately a 20-fold reduction in cell growth and 60% reduction in cell viability as compared to mock-infected cells. Cell cycle analysis, PARP cleavage and changes in cell morphology supported apoptosis as the mechanism of cell death in response to E2F-1. In order to test the efficacy of treatment with a combination of gene therapy and chemotherapy, we utilized concentrations of Ad-E2F-1 which reduced viability to 50% in combination with each chemotherapeutic agent. Cotreatment of the cells with E2F-1 virus and roscovitine (ROS) or etoposide resulted in an additive effect on cell growth inhibition and induction of apoptosis. Interestingly, 5-fluorouracil did not cooperate with Ad-E2F-1 in the mediation of tumor death or inhibition of cell growth. Immunoblotting for Bcl-2 family members revealed no significant changes in the expression levels of Bcl-2, Bcl X(L), Bax or Bak following gene or 'chemogene' therapy with E2F-1. However, a Bax cleavage product was noted

  16. Expression of E2F transcription factor family genes during chick wing development.

    PubMed

    Towers, Matthew; Fisunov, Gleb; Tickle, Cheryll

    2009-10-01

    The E2F family of transcriptional regulators activate or repress gene expression during specific phases of the cell cycle and control various processes including proliferation, apoptosis and differentiation. However, little is known about the developmental roles of E2F transcription factors in higher vertebrates. The chick wing is an excellent system for studying these processes because, in addition to having a rich classical embryology, it is increasingly amenable to molecular and genomic approaches. We show that the human and mouse complement of eight E2F transcription factors is conserved in the chicken and that chicken E2F genes are expressed in different spatial and temporal patterns during wing development. We discuss how the expression patterns of the eight chicken E2F transcription factors might be related to important morphogenetic events.

  17. In vivo delivery of bovine viral diahorrea virus, E2 protein using hollow mesoporous silica nanoparticles

    NASA Astrophysics Data System (ADS)

    Mahony, D.; Cavallaro, A. S.; Mody, K. T.; Xiong, L.; Mahony, T. J.; Qiao, S. Z.; Mitter, N.

    2014-05-01

    Our work focuses on the application of mesoporous silica nanoparticles as a combined delivery vehicle and adjuvant for vaccine applications. Here we present results using the viral protein, E2, from bovine viral diarrhoea virus (BVDV). BVDV infection occurs in the target species of cattle and sheep herds worldwide and is therefore of economic importance. E2 is a major immunogenic determinant of BVDV and is an ideal candidate for the development of a subunit based nanovaccine using mesoporous silica nanoparticles. Hollow type mesoporous silica nanoparticles with surface amino functionalisation (termed HMSA) were characterised and assessed for adsorption and desorption of E2. A codon-optimised version of the E2 protein (termed Opti-E2) was produced in Escherichia coli. HMSA (120 nm) had an adsorption capacity of 80 μg Opti-E2 per mg HMSA and once bound E2 did not dissociate from the HMSA. Immunisation studies in mice with a 20 μg dose of E2 adsorbed to 250 μg HMSA was compared to immunisation with Opti-E2 (50 μg) together with the traditional adjuvant Quillaja saponaria Molina tree saponins (QuilA, 10 μg). The humoral responses with the Opti-E2/HMSA nanovaccine although slightly lower than those obtained for the Opti-E2 + QuilA group demonstrated that HMSA particles are an effective adjuvant that stimulated E2-specific antibody responses. Importantly the cell-mediated immune responses were consistently high in all mice immunised with Opti-E2/HMSA nanovaccine formulation. Therefore we have shown the Opti-E2/HMSA nanoformulation acts as an excellent adjuvant that gives both T-helper 1 and T-helper 2 mediated responses in a small animal model. This study has provided proof-of-concept towards the development of an E2 subunit nanoparticle based vaccine.Our work focuses on the application of mesoporous silica nanoparticles as a combined delivery vehicle and adjuvant for vaccine applications. Here we present results using the viral protein, E2, from bovine viral

  18. Role of Conserved Cysteine Residues in Hepatitis C Virus Glycoprotein E2 Folding and Function

    PubMed Central

    McCaffrey, Kathleen; Boo, Irene; Tewierek, Kevin; Edmunds, Mark L.; Poumbourios, Pantelis

    2012-01-01

    Hepatitis C virus glycoprotein E2 contains 18 conserved cysteines predicted to form nine disulfide pairs. In this study, a comprehensive cysteine-alanine mutagenesis scan of all 18 cysteine residues was performed in E1E2-pseudotyped retroviruses (HCVpp) and recombinant E2 receptor-binding domain (E2 residues 384 to 661 [E2661]). All 18 cysteine residues were absolutely required for HCVpp entry competence. The phenotypes of individual cysteines and pairwise mutation of disulfides were largely the same for retrovirion-incorporated E2 and E2661, suggesting their disulfide arrangements are similar. However, the contributions of each cysteine residue and the nine disulfides to E2 structure and function varied. Individual Cys-to-Ala mutations revealed discordant effects, where removal of one Cys within a pair had minimal effect on H53 recognition and CD81 binding (C486 and C569) while mutation of its partner abolished these functions (C494 and C564). Removal of disulfides at C581-C585 and C452-C459 significantly reduced the amount of E1 coprecipitated with E2, while all other disulfides were absolutely required for E1E2 heterodimerization. Remarkably, E2661 tolerates the presence of four free cysteines, as simultaneous mutation of C452A, C486A, C569A, C581A, C585A, C597A, and C652A (M+C597A) retained wild-type CD81 binding. Thus, only one disulfide from each of the three predicted domains, C429-C552 (DI), C503-C508 (DII), and C607-C644 (DIII), is essential for the assembly of the E2661 CD81-binding site. Furthermore, the yield of total monomeric E2 increased to 70% in M+C597A. These studies reveal the contribution of each cysteine residue and the nine disulfide pairs to E2 structure and function. PMID:22278231

  19. Competing E2 and SN2 Mechanisms for the F(-) + CH3CH2I Reaction.

    PubMed

    Yang, Li; Zhang, Jiaxu; Xie, Jing; Ma, Xinyou; Zhang, Linyao; Zhao, Chenyang; Hase, William L

    2017-02-09

    Anti-E2, syn-E2, inv-, and ret-SN2 reaction channels for the gas-phase reaction of F(-) + CH3CH2I were characterized with a variety of electronic structure calculations. Geometrical analysis confirmed synchronous E2-type transition states for the elimination of the current reaction, instead of nonconcerted processes through E1cb-like and E1-like mechanisms. Importantly, the controversy concerning the reactant complex for anti-E2 and inv-SN2 paths has been clarified in the present work. A positive barrier of +19.2 kcal/mol for ret-SN2 shows the least feasibility to occur at room temperature. Negative activation energies (-16.9, -16.0, and -4.9 kcal/mol, respectively) for inv-SN2, anti-E2, and syn-E2 indicate that inv-SN2 and anti-E2 mechanisms significantly prevail over the eclipsed elimination. Varying the leaving group for a series of reactions F(-) + CH3CH2Y (Y = F, Cl, Br, and I) leads to monotonically decreasing barriers, which relates to the gradually looser TS structures following the order F > Cl > Br > I. The reactivity of each channel nearly holds unchanged except for the perturbation between anti-E2 and inv-SN2. RRKM calculation reveals that the reaction of the fluorine ion with ethyl iodide occurs predominately via anti-E2 elimination, and the inv-SN2 pathway is suppressed, although it is energetically favored. This phenomenon indicates that, in evaluating the competition between E2 and SN2 processes, the kinetic or dynamical factors may play a significant role. By comparison with benchmark CCSD(T) energies, MP2, CAM-B3LYP, and M06 methods are recommended to perform dynamics simulations of the title reaction.

  20. E2F Transcription Factors Control the Roller Coaster Ride of Cell Cycle Gene Expression.

    PubMed

    Thurlings, Ingrid; de Bruin, Alain

    2016-01-01

    Initially, the E2F transcription factor was discovered as a factor able to bind the adenovirus E2 promoter and activate viral genes. Afterwards it was shown that E2F also binds to promoters of nonviral genes such as C-MYC and DHFR, which were already known at that time to be important for cell growth and DNA metabolism, respectively. These findings provided the first clues that the E2F transcription factor might be an important regulator of the cell cycle. Since this initial discovery in 1987, several additional E2F family members have been identified, and more than 100 targets genes have been shown to be directly regulated by E2Fs, the majority of these are important for controlling the cell cycle. The progression of a cell through the cell cycle is accompanied with the increased expression of a specific set of genes during one phase of the cell cycle and the decrease of the same set of genes during a later phase of the cell cycle. This roller coaster ride, or oscillation, of gene expression is essential for the proper progression through the cell cycle to allow accurate DNA replication and cell division. The E2F transcription factors have been shown to be critical for the temporal expression of the oscillating cell cycle genes. This review will focus on how the oscillation of E2Fs and their targets is regulated by transcriptional, post-transcriptional and post-translational mechanism in mammals, yeast, flies, and worms. Furthermore, we will discuss the functional impact of E2Fs on the cell cycle progression and outline the consequences when E2F expression is disturbed.

  1. Agrobacterium delivers VirE2 protein into host cells via clathrin-mediated endocytosis

    PubMed Central

    Li, Xiaoyang; Pan, Shen Q.

    2017-01-01

    Agrobacterium tumefaciens can cause crown gall tumors on a wide range of host plants. As a natural genetic engineer, the bacterium can transfer both single-stranded DNA (ssDNA) [transferred DNA (T-DNA)] molecules and bacterial virulence proteins into various recipient cells. Among Agrobacterium-delivered proteins, VirE2 is an ssDNA binding protein that is involved in various steps of the transformation process. However, it is not clear how plant cells receive the T-DNA or protein molecules. Using a split–green fluorescent protein approach, we monitored the VirE2 delivery process inside plant cells in real time. We observed that A. tumefaciens delivered VirE2 from the bacterial lateral sides that were in close contact with plant membranes. VirE2 initially accumulated on plant cytoplasmic membranes at the entry points. VirE2-containing membranes were internalized through clathrin-mediated endocytosis to form endomembrane compartments. VirE2 colocalized with the early endosome marker SYP61 but not with the late endosome marker ARA6, suggesting that VirE2 escaped from early endosomes for subsequent trafficking inside the cells. Dual endocytic motifs at the carboxyl-terminal tail of VirE2 were involved in VirE2 internalization and could interact with the μ subunit of the plant clathrin-associated adaptor AP2 complex (AP2M). Both the VirE2 cargo motifs and AP2M were important for the transformation process. Because AP2-mediated endocytosis is well conserved, our data suggest that the A. tumefaciens pathogen hijacks conserved endocytic pathways to facilitate the delivery of virulence factors. This might be important for Agrobacterium to achieve both a wide host range and a high transformation efficiency. PMID:28345032

  2. Materials characterization activities for %E2%80%9CTake Our Sons&Daughters to Work Day%E2%80%9D 2013.

    SciTech Connect

    Mowry, Curtis Dale; Pimentel, Adam S.; Sparks, Elizabeth Schares; Hanlon, Brittany Paula

    2013-09-01

    We created interactive demonstration activities for Take Our Daughters&Sons to Work Day (TODSTWD) 2013 in order to promote general interest in chemistry and also generate awareness of the type of work our laboratories can perform. %E2%80%9CCurious about Mars Rover Curiosity?%E2%80%9D performed an elemental analysis on rocks brought to our lab using the same technique utilized on the planet Mars by the NASA robotic explorer Curiosity. %E2%80%9CFood is Chemistry?%E2%80%9D utilized a mass spectrometer to measure, in seconds, each participant's breath in order to identify the food item consumed for the activity. A total of over 130 children participated in these activities over a 3 hour block, and feedback was positive. This document reports the materials (including handouts), experimental procedures, and lessons learned so that future demonstrations can benefit from the baseline work performed. We also present example results used to prepare the Food activity and example results collected during the Curiosity demo.

  3. How alkyl halide structure affects E2 and SN2 reaction barriers: E2 reactions are as sensitive as SN2 reactions.

    PubMed

    Rablen, Paul R; McLarney, Brett D; Karlow, Brandon J; Schneider, Jean E

    2014-02-07

    High-level electronic structure calculations, including a continuum treatment of solvent, are employed to elucidate and quantify the effects of alkyl halide structure on the barriers of SN2 and E2 reactions. In cases where such comparisons are available, the results of these calculations show close agreement with solution experimental data. Structural factors investigated include α- and β-methylation, adjacency to unsaturated functionality (allyl, benzyl, propargyl, α to carbonyl), ring size, and α-halogenation and cyanation. While the influence of these factors on SN2 reactivity is mostly well-known, the present study attempts to provide a broad comparison of both SN2 and E2 reactivity across many cases using a single methodology, so as to quantify relative reactivity trends. Despite the fact that most organic chemistry textbooks say far more about how structure affects SN2 reactions than about how it affects E2 reactions, the latter are just as sensitive to structural variation as are the former. This sensitivity of E2 reactions to structure is often underappreciated.

  4. Combined effects of E2F1 and E2F2 polymorphisms on risk and early onset of squamous cell carcinoma of the head and neck

    PubMed Central

    Lu, Meixia; Liu, Zhensheng; Yu, Hongping; Wang, Li-E; Li, Guojun; Sturgis, Erich M.; Johnson, David G.; Wei, Qingyi

    2012-01-01

    Deregulated expression of most members of the E2F family has been detected in many human cancers. We examined the association of common single nucleotide polymorphisms (SNPs) of E2F1 and E2F2 with risk of squamous cell carcinoma of the head and neck (SCCHN) in 1,096 SCCHN patients and 1,090 cancer-free controls. We genotyped ten selected SNPs in E2F1 and E2F2, including those at the near 5′ UTR, miRNA binding sites at the near 3′ UTR and tagSNPs according to bioinfotmatics analysis. Although none of the selected SNPs alone was significantly associated with risk of SCCHN, there was a statistically significantly increased risk of SCCHN associated with the combined risk genotypes (i.e. rs3213182 AA, rs3213183 GG, rs3213180 GG, rs321318121 GG, rs2742976 GT+TT, rs6667575 GA+AA, rs3218203 CC, rs3218148 AA, rs3218211 CC, rs3218123 GT+TT). Compared with those with 0–4 risk genotypes, an increased risk was observed for those who carried 5–8 risk genotypes (adjusted OR = 1.04; 95% CI = 0.86–1.26) and 9–10 risk genotypes (adjusted OR = 1.62; 95% CI = 1.14–2.30) in a dose-response manner (P = 0.045). Furthermore, the joint effect was more pronounced among patients with oropharyngeal cancer, younger adults (≤57 years old), men, non-smokers, non-drinkers, and individuals with family history of cancer first-degree relatives. Additionally, we also observed that those with 5–10 risk genotypes had an earlier SCCHN onset than those with 0–4 risk genotypes, particularly for non-smokers and/or non-drinkers. We concluded that E2F1 and E2F2 genetic variants may jointly play important roles in head and neck carcinogenesis. PMID:22344756

  5. OTUB1 Co-opts Lys48-Linked Ubiquitin Recognition to Suppress E2 Enzyme Function

    SciTech Connect

    Juang, Yu-Chi; Landry, Marie-Claude; Sanches, Mario; Vittal, Vinayak; Leung, Charles C.Y.; Ceccarelli, Derek F.; Mateo, Abigail-Rachele F.; Pruneda, Jonathan N.; Mao, Daniel Y.L.; Szilard, Rachel K.; Orlicky, Stephen; Munro, Meagan; Brzovic, Peter S.; Klevit, Rachel E.; Sicheri, Frank; Durocher, Daniel

    2012-03-26

    Ubiquitylation entails the concerted action of E1, E2, and E3 enzymes. We recently reported that OTUB1, a deubiquitylase, inhibits the DNA damage response independently of its isopeptidase activity. OTUB1 does so by blocking ubiquitin transfer by UBC13, the cognate E2 enzyme for RNF168. OTUB1 also inhibits E2s of the UBE2D and UBE2E families. Here we elucidate the structural mechanism by which OTUB1 binds E2s to inhibit ubiquitin transfer. OTUB1 recognizes ubiquitin-charged E2s through contacts with both donor ubiquitin and the E2 enzyme. Surprisingly, free ubiquitin associates with the canonical distal ubiquitin-binding site on OTUB1 to promote formation of the inhibited E2 complex. Lys48 of donor ubiquitin lies near the OTUB1 catalytic site and the C terminus of free ubiquitin, a configuration that mimics the products of Lys48-linked ubiquitin chain cleavage. OTUB1 therefore co-opts Lys48-linked ubiquitin chain recognition to suppress ubiquitin conjugation and the DNA damage response.

  6. Capturing a substrate in an activated RING E3/E2-SUMO complex

    PubMed Central

    Streich, Frederick C.; Lima, Christopher D.

    2016-01-01

    Summary Post-translational protein modification by ubiquitin (Ub) and ubiquitin-like (Ubl) proteins such as small ubiquitin like modifier (SUMO) regulates processes including protein homeostasis, the DNA damage response, and the cell cycle. Proliferating cell nuclear antigen (PCNA) is modified by Ub or poly-Ub at Lys164 after DNA damage to recruit repair factors. Yeast PCNA is modified by SUMO on Lys164 and Lys127 during S-phase to recruit the anti-recombinogenic helicase Srs2. Lys164 modification requires specialized E2/E3 enzyme pairs for SUMO or Ub conjugation. For SUMO, Lys164 modification is strictly dependent on the E3 ligase Siz1, suggesting the E3 alters E2 specificity to promote Lys164 modification. The structural basis for substrate interactions in activated E3/E2-Ub/Ubl complexes remains unclear. Here, we report an engineered E2 protein and cross-linking strategies that trap an E3/E2-Ubl/substrate complex for structure determination, illustrating how an E3 can bypass E2 specificity to force-feed a substrate lysine into the E2 active site. PMID:27509863

  7. Highly sensitive detection of E2 activity in ubiquitination using an artificial RING finger.

    PubMed

    Miyamoto, Kazuhide; Sumida, Miho; Yuasa-Sunagawa, Mayumi; Saito, Kazuki

    2017-03-01

    The ubiquitin-conjugating (E2) enzymes of protein ubiquitination are associated with various diseases such as leukemia, lung cancer, and breast cancer. Rapid and accurate detection of E2 enzymatic activities remains poor. Here, we described the detection of E2 activity on a signal accumulation ISFET biosensor (AMIS sensor) using an artificial RING finger (ARF). The use of ARF enables the simplified detection of E2 activity without a substrate. The high-sensitivity quantitative detection of E2 activities was demonstrated via real-time monitoring over a response range of femtomolar to micromolar concentrations. Furthermore, the monitoring of E2 activities was successfully achieved using human acute promyelocytic leukemia cells following treatment with the anticancer drug bortezomib, which allowed the assessment of the pathological conditions. This strategy is extremely simple and convenient, and the present detection could be widely applied to specific E2s for various types of cancers. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.

  8. MEF/ELF4 transactivation by E2F1 is inhibited by p53.

    PubMed

    Taura, Manabu; Suico, Mary Ann; Fukuda, Ryosuke; Koga, Tomoaki; Shuto, Tsuyoshi; Sato, Takashi; Morino-Koga, Saori; Okada, Seiji; Kai, Hirofumi

    2011-01-01

    Myeloid elf-1-like factor (MEF) or Elf4 is an E-twenty-six (ETS)-related transcription factor with strong transcriptional activity that influences cellular senescence by affecting tumor suppressor p53. MEF downregulates p53 expression and inhibits p53-mediated cellular senescence by transcriptionally activating MDM2. However, whether p53 reciprocally opposes MEF remains unexplored. Here, we show that MEF is modulated by p53 in human cells and mice tissues. MEF expression and promoter activity were suppressed by p53. While we found that MEF promoter does not contain p53 response elements, intriguingly, it contains E2F consensus sites. Subsequently, we determined that E2F1 specifically binds to MEF promoter and transactivates MEF. Nevertheless, E2F1 DNA binding and transactivation of MEF promoter was inhibited by p53 through the association between p53 and E2F1. Furthermore, we showed that activation of p53 in doxorubicin-induced senescent cells increased E2F1 and p53 interaction, diminished E2F1 recruitment to MEF promoter and reduced MEF expression. These observations suggest that p53 downregulates MEF by associating with and inhibiting the binding activity of E2F1, a novel transcriptional activator of MEF. Together with previous findings, our present results indicate that a negative regulatory mechanism exists between p53 and MEF.

  9. Genomic and Genetic Variation in E2F1 in Men with Non-Obstructive Azoospermia

    PubMed Central

    Jorgez, Carolina J.; Wilken, Nathan; Addai, Josephine B.; Newberg, Justin; Vangapandu, Hima V.; Pastuszak, Alexander W.; Mukherjee, Sarmistha; Rosenfeld, Jill A.; Lipshultz, Larry I.; Lamb, Dolores J.

    2014-01-01

    Objective To identify gene dosage changes associated with non-obstructive azoospermia (NOA) using array comparative genomic hybridization (aCGH). Design Prospective study. Patients 110 men with NOA and 78 fertile controls. Settings Medical School Interventions None Main Outcome Measure The study has four distinct analytic components: aCGH, a molecular karyotype that detects copy-number-variations (CNV), Taqman-CNV assays to validate CNVs, mutation identification by Sanger sequencing and histologic analyses of testicular tissues. Results A microduplication at 20q11.22 encompassing E2F1 was identified in one of eight men with NOA analyzed using aCGH. CNVs were confirmed and an additional 102 men with NOA screened using Taqman CNV assays for a total of 110 NOA men analyzed for CNVs in E2F1. Eight of 110 (7.3%) NOA men had microduplications or microdeletions of E2F1 that were absent in fertile controls. Conclusions E2F1 microduplications or microdeletions are present in NOA men (7.3%). Duplications or deletions of E2F1 occur very rarely in the general population (0.011%), but E2F1 gene dosage changes, previously reported only in cancers, are present in a subset of NOA men. These results recapitulate the infertility phenotype seen in mice lacking or over-expressing E2f1. PMID:25439843

  10. Insights into Nuclear Triaxiality from Interference Effects in E2 Matrix Elements

    NASA Astrophysics Data System (ADS)

    Allmond, J. M.; Wood, J. L.; Kulp, W. D.

    2007-10-01

    Recently, we have introduced [1] a triaxial rotor model with independent inertia and E2 tensors. The E2 matrix elements [2] of the osmium isotopes (186, 188, 190, and 192) are studied in the framework of this model (59 of 84 E2 matrix elements deviate by 30% or less). It is shown that interference effects in the inertia tensor (K-mixing) and the E2 tensor can lead to significant reductions in the diagonal E2 matrix elements. In some instances, the diagonal E2 matrix elements may decrease with increasing spin. Additionally, a sum rule for diagonal E2 matrix elements is shown and used to explore missing strength from K-admixtures. [1] J.L. Wood, A-M. Oros-Peusquens, R. Zaballa, J.M. Allmond, and W.D. Kulp, Phys. Rev. C 70, 024308 (2004). [2] C.Y. Wu, D. Cline, T. Czosnyka, A. Backlin, C. Baktash, R.M. Diamond, G.D. Dracoulis, L. Hasselgren, H. Kluge, et al., Nucl. Phys. A607, 178 (1996).

  11. Isolation of a differentially regulated splicing isoform of human NF-E2.

    PubMed Central

    Pischedda, C; Cocco, S; Melis, A; Marini, M G; Kan, Y W; Cao, A; Moi, P

    1995-01-01

    The transcription factor NF-E2 (nuclear factor erythroid 2), interacting via DNA motifs within regulatory regions of several hematopoietic genes, is thought to mediate the enhancer activity of the globin locus control regions. By screening a human fetal liver cDNA library with probes derived from mouse NF-E2, we have isolated a splicing variant of the NF-E2 gene (fNF-E2) that differs in the 5' untranslated region from the previously reported cDNA (aNF-E2). The fNF-E2 isoform is transcribed from an alternative promoter located in the 3' end of the first intron and joined by alternative splicing to the second and third exons, which are shared by both RNA isoforms. Although the two forms produce the same protein, they are expressed in different ratios during development. fNF-E2 is more abundant in the fetal liver and less abundant in the adult bone marrow compared to the previously described form. Their distribution apparently follows the differential expression of fetal and adult hemoglobins. Images Fig. 5 Fig. 6 Fig. 7 PMID:7724591

  12. Several different upstream promoter elements can potentiate transactivation by the BPV-1 E2 protein.

    PubMed Central

    Ham, J; Dostatni, N; Arnos, F; Yaniv, M

    1991-01-01

    The enhancer and upstream promoter regions of RNA polymerase II transcribed genes modulate the rate of transcription initiation and establish specific patterns of gene expression. Both types of region consist of clusters of DNA binding sites for nuclear proteins. To determine how efficiently the same factor can activate transcription when acting as an enhancer or promoter factor, we have studied transactivation by the BPV-1 E2 protein, a papillomavirus transcriptional regulator. By cotransfecting a BPV-1 E2 expression vector and a series of reporter plasmids containing well-defined chimeric promoters we have found that whilst E2 can strongly stimulate complex promoters such as that of the HSV tk gene, it does not efficiently activate constructions containing only a TATA box and initiation site. We show that insertion of upstream promoter elements, but not of spacer DNA, between E2 binding sites and the TATA box greatly increases E2 activation. This effect was observed with more than one type of upstream promoter element, is not related to the strength of the promoter and is unlikely to result from co-operative DNA binding by E2 and the transcription factors tested. These results would suggest that E2 has the properties of an enhancer rather than promoter factor and that in certain cases promoter and enhancer factors may affect different steps in the process of transcriptional activation. Images PMID:1655407

  13. Phosphorylation regulates binding of the human papillomavirus type 8 E2 protein to host chromosomes.

    PubMed

    Sekhar, Vandana; McBride, Alison A

    2012-09-01

    The papillomavirus E2 proteins are indispensable for the viral life cycle, and their functions are subject to tight regulation. The E2 proteins undergo posttranslational modifications that regulate their properties and roles in viral transcription, replication, and genome maintenance. During persistent infection, the E2 proteins from many papillomaviruses act as molecular bridges that tether the viral genomes to host chromosomes to retain them within the host nucleus and to partition them to daughter cells. The betapapillomavirus E2 proteins bind to pericentromeric regions of host mitotic chromosomes, including the ribosomal DNA loci. We recently reported that two residues (arginine 250 and serine 253) within the chromosome binding region of the human papillomavirus type 8 (HPV8) E2 protein are required for this binding. In this study, we show that serine 253 is phosphorylated, most likely by protein kinase A, and this modulates the interaction of the E2 protein with cellular chromatin. Furthermore, we show that this phosphorylation occurs in S phase, increases the half-life of the E2 protein, and promotes chromatin binding from S phase through mitosis.

  14. Atypical E2F activity coordinates PHR1 photolyase gene transcription with endoreduplication onset.

    PubMed

    Radziejwoski, Amandine; Vlieghe, Kobe; Lammens, Tim; Berckmans, Barbara; Maes, Sara; Jansen, Marcel A K; Knappe, Claudia; Albert, Andreas; Seidlitz, Harald K; Bahnweg, Günther; Inzé, Dirk; De Veylder, Lieven

    2011-01-19

    Because of their sessile life style, plants have evolved the ability to adjust to environmentally harsh conditions. An important aspect of stress adaptation involves the reprogramming of the cell cycle to ensure optimal growth. The atypical E2F transcription factor DP-E2F-like 1 (E2Fe/DEL1) had been found previously to be an important regulator of the endocycle onset. Here, a novel role for E2Fe/DEL1 was identified as a transcriptional repressor of the type-II cyclobutane pyrimidine dimer-photolyase DNA repair gene PHR1. Upon ultraviolet-B (UV-B) treatment, plants knocked out for E2Fe/DEL1 had improved DNA repair abilities when compared with control plants, whereas those overexpressing it performed less well. Better DNA repair allowed E2Fe/DEL1 knockout plants to resume endoreduplication faster than control plants, contributing in this manner to UV-B radiation resistance by compensating the stress-induced reduction in cell number by ploidy-dependent cell growth. As E2Fe/DEL1 levels decreased upon UV-B treatment, we hypothesize that the coordinated transcriptional induction of PHR1 with the endoreduplication onset contributes to the adaptation of plants exposed to UV-B stress.

  15. Atypical E2F activity coordinates PHR1 photolyase gene transcription with endoreduplication onset

    PubMed Central

    Radziejwoski, Amandine; Vlieghe, Kobe; Lammens, Tim; Berckmans, Barbara; Maes, Sara; Jansen, Marcel A K; Knappe, Claudia; Albert, Andreas; Seidlitz, Harald K; Bahnweg, Günther; Inzé, Dirk; De Veylder, Lieven

    2011-01-01

    Because of their sessile life style, plants have evolved the ability to adjust to environmentally harsh conditions. An important aspect of stress adaptation involves the reprogramming of the cell cycle to ensure optimal growth. The atypical E2F transcription factor DP-E2F-like 1 (E2Fe/DEL1) had been found previously to be an important regulator of the endocycle onset. Here, a novel role for E2Fe/DEL1 was identified as a transcriptional repressor of the type-II cyclobutane pyrimidine dimer-photolyase DNA repair gene PHR1. Upon ultraviolet-B (UV-B) treatment, plants knocked out for E2Fe/DEL1 had improved DNA repair abilities when compared with control plants, whereas those overexpressing it performed less well. Better DNA repair allowed E2Fe/DEL1 knockout plants to resume endoreduplication faster than control plants, contributing in this manner to UV-B radiation