Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Ann Rheum Dis ; 80(10): 1330-1338, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34127481

RESUMO

INTRODUCTION: Vaccination represents a cornerstone in mastering the COVID-19 pandemic. Data on immunogenicity and safety of messenger RNA (mRNA) vaccines in patients with autoimmune inflammatory rheumatic diseases (AIIRD) are limited. METHODS: A multicentre observational study evaluated the immunogenicity and safety of the two-dose regimen BNT162b2 mRNA vaccine in adult patients with AIIRD (n=686) compared with the general population (n=121). Serum IgG antibody levels against SARS-CoV-2 spike S1/S2 proteins were measured 2-6 weeks after the second vaccine dose. Seropositivity was defined as IgG ≥15 binding antibody units (BAU)/mL. Vaccination efficacy, safety, and disease activity were assessed within 6 weeks after the second vaccine dose. RESULTS: Following vaccination, the seropositivity rate and S1/S2 IgG levels were significantly lower among patients with AIIRD versus controls (86% (n=590) vs 100%, p<0.0001 and 132.9±91.7 vs 218.6±82.06 BAU/mL, p<0.0001, respectively). Risk factors for reduced immunogenicity included older age and treatment with glucocorticoids, rituximab, mycophenolate mofetil (MMF), and abatacept. Rituximab was the main cause of a seronegative response (39% seropositivity). There were no postvaccination symptomatic cases of COVID-19 among patients with AIIRD and one mild case in the control group. Major adverse events in patients with AIIRD included death (n=2) several weeks after the second vaccine dose, non-disseminated herpes zoster (n=6), uveitis (n=2), and pericarditis (n=1). Postvaccination disease activity remained stable in the majority of patients. CONCLUSION: mRNA BNTb262 vaccine was immunogenic in the majority of patients with AIIRD, with an acceptable safety profile. Treatment with glucocorticoids, rituximab, MMF, and abatacept was associated with a significantly reduced BNT162b2-induced immunogenicity.


Assuntos
Doenças Autoimunes/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Hospedeiro Imunocomprometido/imunologia , Imunogenicidade da Vacina/imunologia , Doenças Reumáticas/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Doenças Autoimunes/tratamento farmacológico , Vacina BNT162 , Vacinas contra COVID-19/efeitos adversos , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Doenças Reumáticas/tratamento farmacológico , SARS-CoV-2 , Adulto Jovem
2.
J Cell Biochem ; 108(5): 1203-10, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19795383

RESUMO

Several lines of evidence suggest that aldosterone excess may have detrimental effects in the cardiovascular system, independent of its interaction with the renal epithelial cells. Here we examined the possibility that aldosterone modulates 12- and/or 15-lipoxygenase (LO) expression/activity in human vascular smooth muscle cells (VSMC), in vitro, thereby potentially contributing to both vascular reactivity and atherogenesis. Following 24 h treatment of VSMC with aldosterone (1 nmol/L), there was a approximately 2-fold increase in the generation rate of 12 hydroxyeicosatetraenoic acid (12-HETE), 70% increase in platelet type 12-LO mRNA expression (P < 0.001) along with a approximately 3-fold increase in 12-LO protein expression, which were blocked by the mineralocorticoid receptor (MR) antagonists spironolactone (100 nmol/L) and eplerelone (100 nmol/ml). Additionally, aldosterone (1 nmol/L; 24 h) increased the production of 15-HETE (50%; P < 0.001) and the expression of 15-LO type 2 mRNA (50%; P < 0.05) (in VSMC). Aldosterone also increased the 12- and 15-LO type 2 mRNA expression in a line of human aortic smooth muscle cells (T/G HA-VSMC) (60% and 50%, respectively). Aldosterone-induced 12- and 15-LO type 2 mRNA expressions were blocked by the EGF-receptor antagonist AG 1478 and by the MAPK-kinase inhibitor UO126. Aldosterone-treated VSMC also showed increased LDL oxidation, (approximately 2-fold; P < 0.001), which was blocked by spironolactone. In conclusion, aldosterone increased 12- and 15-LO expression in human VSMC, in association with increased 12- and 15-HETE generation and enhanced LDL oxidation and may directly augment VSMC contractility, hypertrophy, and migration through 12-HETE and promote LDL oxidation via the pro-oxidative properties of these enzymes.


Assuntos
Aldosterona/metabolismo , Araquidonato 12-Lipoxigenase/metabolismo , Araquidonato 15-Lipoxigenase/metabolismo , Lipoproteínas LDL/metabolismo , Miócitos de Músculo Liso/metabolismo , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/metabolismo , Aldosterona/farmacologia , Araquidonato 12-Lipoxigenase/genética , Araquidonato 15-Lipoxigenase/genética , Linhagem Celular , Receptores ErbB/metabolismo , Humanos , Ácidos Hidroxieicosatetraenoicos/metabolismo , Antagonistas de Receptores de Mineralocorticoides , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Oxirredução , Receptores de Mineralocorticoides/metabolismo , Regulação para Cima
3.
Am J Hypertens ; 21(2): 219-23, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18202670

RESUMO

BACKGROUND: Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is a member of the nuclear receptor family that has been implicated in cell differentiation and proliferation, glucose metabolism, macrophage development, and inflammatory responses. PPAR-gamma can be activated by a range of synthetic substances and also by products of lipid oxidation such as oxidized low-density lipoprotein, 13-hydroxyoctadecadienoic acid (13-HODE) and 15-hydroxyeicosatetraenoic acid (15-HETE). Since 12- and 15-lipoxygenase (12- and 15-LO) are expressed in human vascular smooth muscle cells (VSMCs), we set out to investigate the possible relation between PPAR-gamma and LO system in these cells. METHODS: In vitro experiments in human VSMC using standard methods. RESULTS: The LO products, 12-HETE (10(-7) mol/l), 15-HETE (10(-7) mol/l) and 13-HODE (10(-7) mol//l) increased the expression of PPAR-gamma-2 messenger RNA (mRNA) in VSMC (by 100, 50, and 100%, respectively. Rosiglitazone (1-10 micromol/l) was found to upregulate both the mRNA expression of two LO enzymes, platelet-type 12-lipoxygenase (12-LO; +70%) and 15-lipoxygenase type 2 (15-LO; +60%), and the secretion of their eicosanoid products 12- and 15-HETE. In addition, rosiglitazone-induced a threefold increase in PPAR-gamma-2 mRNA expressions and modest 50% rise in PPAR-gamma-1 mRNA expression. The effect of rosiglitazone on PPAR-gamma-2 could be entirely blocked by the LO inhibitor baicalein and restored by the addition of exogenous 12-HETE. CONCLUSIONS: These results suggest a novel amplification cycle in which PPAR-gamma activation induces production of 12- and 15-LO-derived metabolites which in turn feed back to upregulate PPAR-gamma-2's own expression. The implications of this link in VSMC pathophysiology remain to be elucidated.


Assuntos
Araquidonato 12-Lipoxigenase/metabolismo , Araquidonato 15-Lipoxigenase/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/enzimologia , PPAR gama/genética , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/metabolismo , Araquidonato 12-Lipoxigenase/genética , Araquidonato 15-Lipoxigenase/genética , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Humanos , Ácidos Hidroxieicosatetraenoicos/metabolismo , Hipoglicemiantes/farmacologia , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Rosiglitazona , Tiazolidinedionas/farmacologia , Cordão Umbilical/citologia , Regulação para Cima/fisiologia
4.
J Steroid Biochem Mol Biol ; 107(3-5): 238-44, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17659868

RESUMO

Human osteoblasts (hOB) produce and respond to 1,25(OH)(2)D(3) (1,25D), suggesting an autocrine/paracrine system. We therefore examined hormonal modulation of the expression and activity of 25 hydroxy-vitamin D(3)-1alpha hydroxylase (1-Ohase) in hOB. Cells from pre- and post-menopausal women or men, were treated with estrogenic compounds and 1-OHase expression and activity were measured. 1-OHase mRNA expression was highest in pre-menopausal women hOB and was increased by all hormones tested. In post-menopausal hOB all hormones except biochainin A (BA) and genistein (G) increased 1-OHase mRNA expressions to less extent. In male-derived hOB only dihydrotestosterone (DHT) and carboxy BA (cBA) increased 1-OHase mRNA expression. 1,25D production from 25(OH)D(3) had a K(m) of approximately 769-400 ng/ml (1.92-1.07 microM) and V(max) of 31.3-17.4 ng/ml (0.078-0.044 microM/60 min/5 x 10(6)cells) respectively, and was increased by all hormones except raloxifene (Ral) with higher stimulation in pre- than in post-menopausal cells. Only BA was almost five times more potent in pre- rather than post-menopausal hOBs. In male hOB only DHT and cBA increased 1,25D production whereas estradiol-17beta (E(2)) had no effect and BA decreased it. These results provide evidence for the expression of 1-OHase mRNA and production of 1,25D in hOBs, which are age and sex dependent and are hormonally modulated. The role of this local autocrine/paracrine 1,25D system in bone physiology deserves further investigation.


Assuntos
25-Hidroxivitamina D3 1-alfa-Hidroxilase/metabolismo , Di-Hidrotestosterona/farmacologia , Estrogênios/farmacologia , Osteoblastos/efeitos dos fármacos , Hormônio Paratireóideo/farmacologia , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , Sequência de Bases , Células Cultivadas , Primers do DNA , Humanos , Osteoblastos/enzimologia , RNA Mensageiro/genética
5.
Circulation ; 111(13): 1666-71, 2005 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-15795327

RESUMO

BACKGROUND: 1,25(OH)2 vitamin D3 exerts multiple effects in human vascular smooth muscle cells (VSMCs). We therefore tested the possibility that VSMCs possess an endogenous 25-hydroxyvitamin D3-1alpha-hydroxylase system, the final enzyme in the biosynthetic pathway of 1,25(OH)2D3. METHODS AND RESULTS: We assessed the expression and activity of 25-hydroxyvitamin D3-1alpha-hydroxylase by real-time polymerase chain reaction and the conversion of 25(OH)D3 into 1,25(OH)2D3. First, 25-hydroxyvitamin D3-1alpha-hydroxylase mRNA was identified in cultured VSMCs by real-time polymerase chain reaction. Second, in cells treated daily (3 days) with parathyroid hormone (66 nmol/L), estradiol-17beta (30 nmol/L), raloxifene (3 micromol/L), and the phytoestrogens genistein (3 micromol/L), biochainin A (3 micromol/L), and 6-carboxy biochainin A (30 nmol/L), 25-hydroxyvitamin D3-1alpha-hydroxylase mRNA increased by 43+/-13%, (P<0.05) 7+/-24% (P=NS), 176+/-28% (P<0.01), 65+/-11% (P<0.05), 152+/-24% (P<0.01), and 71+/-9% (P<0.05), respectively. Third, production of 1,25(OH)2D3 from 25(OH)D3 was seen with a Km of 25 ng/mL and increased dose dependently after treatment with parathyroid hormone, genistein, and the phytosetrogen derivative 6-carboxy biochainin A. Estradiol-17beta and biochainin A also increased the generation of 1,25(OH)2D3 by 40+/-23% (P<0.05) and 55+/-13% (P<0.05), respectively. CONCLUSIONS: We provide here the first evidence for the expression of an enzymatically active 25(OH)D3-1alpha-hydroxylase system in human VSMCs, which can be upregulated by parathyroid hormone and estrogenic compounds. Because exogenous vitamin D inhibits VSMC proliferation, the role of this system as an autocrine mechanism to curb changes in VSMC proliferation and phenotype is a subject for future investigation.


Assuntos
25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , Estrogênios/farmacologia , Músculo Liso Vascular/enzimologia , Hormônio Paratireóideo/farmacologia , Regulação para Cima/efeitos dos fármacos , Comunicação Autócrina , Calcitriol/biossíntese , Proliferação de Células , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Cinética , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , RNA Mensageiro/análise , Artérias Umbilicais/citologia
6.
J Steroid Biochem Mol Biol ; 99(2-3): 139-46, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16621514

RESUMO

We have reported previously, that female-derived bone cells responded to 17beta-estradiol (E(2)) and to raloxifene (Ral), whereas male-derived cells responded only to dihydrotestosterone (DHT) when the stimulation of creatine kinase specific activity (CK), which is a marker for hormone responsiveness, was measured. In cells derived from pre-menopausal women, E(2), G, D and Ral stimulated CK to higher extent compared to post-menopausal bone cells, whereas quecertin (Qu), carboxy-biochainin A (cBA) and carboxy-genistein (cG) stimulated CK in both age groups similarly, and biochainin A (BA) stimulated post-menopausal cells to a bit higher extent than pre-menopausal cells. Since the skeletal protective effects of estrogens are not discernable in diabetic women, we tested in this study, the effects of high glucose concentration in the growth medium, on the effects of estrogenic compounds on CK in human-derived bone cells (hObs). Female-derived hObs were grown either in normal (4.5 g/l; 22 mM, NG) or high glucose (9.0 g/l; 44 mM, HG) for 7 days. HG increased constitutive CK, but attenuated E(2)- and DHT-induced CK in female or male hObs, respectively. HG also inhibited genistein (G) and daidzein (D) stimulated CK in female hObs, but not the effects of biochainin A (BA), quecertin (Qu) or Ral. Intracellular, mainly nuclear binding of (3)[H]E(2) was characteristic of the different phytoestrogens in female hObs, was abolished by HG. Membranal binding of Eu-Ov-E(2), was displaced only by E(2)-Ov, ICI, cG-Ov or cD-Ov but decreased total binding of Eu-Ov-E(2) in both age groups and completely abolished the competition with E(2)-Ov or ICI in both age groups, but the competition with cD-Ov and cG-Ov was decreased only slightly but not statistically significant. HG also abolished Eu-BSA-T, which bound similarly male-derived hObs. All hObs expressed mRNA for ERalpha and ERbeta with higher abundance of ERalpha. HG increased mRNA for both ERs in female-derived hObs, but decreased mRNA for both ERs in male-derived hObs. Hence, human bone cells, which express specific nuclear and membranal binding sites for estrogenic compounds, are modulated by HG, leading to altered hormonal responsiveness, which might block important effects of estrogenic compounds, contributing probably to their decreased skeletal preserving properties under hyperglycemia.


Assuntos
Estradiol/farmacologia , Glucose/farmacologia , Osteoblastos/efeitos dos fármacos , Fitoestrógenos/farmacologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Ligação Competitiva/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Creatina Quinase Forma BB/metabolismo , Di-Hidrotestosterona/farmacologia , Relação Dose-Resposta a Droga , Estradiol/metabolismo , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Feminino , Expressão Gênica/efeitos dos fármacos , Genisteína/análogos & derivados , Genisteína/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteoblastos/citologia , Osteoblastos/metabolismo , Fitoestrógenos/metabolismo , Quercetina/farmacologia , Fatores Sexuais
7.
J Steroid Biochem Mol Biol ; 98(2-3): 139-46, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16406510

RESUMO

We have reported previously, that female-derived bone cells responded to 17beta-estradiol (E(2)) and raloxifene (Ral), and male-derived cells responded only to dihydrotestosterone (DHT) when the stimulation of creatine kinase specific activity (CK), which is a marker for hormone responsiveness, was measured. We also found that pre-treatment with the less-calcemic analog of Vitamin D, JK 1624 F(2)-2 (JKF), upregulated the response of CK to E(2) and Ral. In this study, we analyzed the response of human bone cells from pre- and post-menopausal females and males, to phytoestrogens. Bone cells derived from pre-menopausal women showed greater stimulation of CK than cells from post-menopausal women, after treatment with E(2) (30 nM), daidzein (D, 3000 nM), genistein (G, 3000 nM) and Ral (3000 nM); whereas the responses to biochainin A (BA 3000 nM), quecertin (Qu 3000 nM) or the carboxy derivative of G (cG 300 nM) were not age-dependent. Male-derived cells did not respond to phytoestrogens. When cells derived from female bones at both age groups were pre-treated with JKF, by daily addition of 1nM, for 3 days, there was an upregulation of the response to E(2), Ral, G and D but not to BA or Qu. Nuclear binding of (3)[H] E(2) was characteristic of the different phytoestrogens, with increase of the specific binding after pre-treatment with JKF. In contrast, the membranal binding of E(2)-Ov-Eu, which was specific for the estrogenic compounds except Ral, was inhibited by pre-treatment with JKF except for ICI 161480 (ICI). Male bone cells did not bind E(2)-Ov-Eu but bound T-BSA-Eu; this binding was abolished by pre-treatment with JKF. Pre-treatment with JKF increased mRNA for ERalpha and decreased mRNA for ERbeta in bone cells from both age groups of females and from males, all of which expressed both ERs, with a ratio of ERalpha to ERbeta of 121:1 in pre- and 78:1 in post-menopausal and 105:1 in male bone cells. This study raises the possibility of combined Vitamin D analog and phytoestrogen for hormonal replacement therapy to prevent post-menopausal osteoporosis, which is a subject of ongoing research in animal models.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Calcitriol/análogos & derivados , Osteoblastos/metabolismo , Fitoestrógenos/farmacologia , Vitamina D/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/metabolismo , Calcitriol/metabolismo , Calcitriol/farmacologia , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Creatina Quinase/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Fitoestrógenos/metabolismo , Ligação Proteica , RNA Mensageiro/metabolismo , Vitamina D/metabolismo , Vitamina D/farmacologia
8.
Am J Hypertens ; 17(5 Pt 1): 462-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15110908

RESUMO

The present study was designed to determine whether some of the effects of estrogen on human vascular cell growth are exerted through membrane-binding sites, using native as well as novel protein-bound, membrane non-permeant estrogenic complexes. We measured changes in DNA synthesis and creatine kinase-specific activity (CK), after treatment with estradiol-17beta (E(2)), estradiol-17beta-6-(O)-carboxymethyl oxime conjugated to bovine serum albumin (BSA) (E(2)-BSA), 6-carboxymethyl genistein (CG) or 6- carboxymethyl genistein bound to the high molecular protein keyhole limpet hemocyanin (CG-KLH), and 7-(O)-carboxymethyl daidzein (CD) or 7-(O)-carboxymethyl daidzein linked to keyhole limpet hemocyanin (CD-KLH). High concentrations of either E(2) or E(2)-BSA inhibited DNA synthesis in vascular smooth muscle cells (VSMC) (-39% +/- 28% v -32% +/- 15%). Estradiol as well as CG and CD increased DNA synthesis dose dependently in endothelial ECV-304 cells. The CG and CD, as well as CG-KLH and CD-KLH, stimulated DNA synthesis dose dependently in VSMC (66% +/- 2%, 100% +/- 12%, 66% +/- 6%, and 41% +/- 8% at 300 nmol/L, respectively). In contrast all forms of protein-bound hormones were unable to affect DNA synthesis in ECV-304 cells or CK in either cell type. In VSMC, both free and bound hormones increased mitogen-activated protein-kinase (MAPK)-kinase activity, which was blocked by UO126, an inhibitor of MAPK-kinase. Furthermore, the effects of E(2), E(2)-BSA, or CG-KLH on DNA synthesis were inhibited by UO126. Using the E(2)-BSA linked to the fluorescent dye Cy3.5, we directly demonstrated the presence of membrane-binding sites for E(2) in VSMC and ECV 304 cells. Hence, the effects of E(2) on DNA synthesis in human VSMC, but not in endothelial cells, are apparently exerted by membrane-binding sites for E(2) and do not require intracellular entry of E(2) through the classic nuclear receptor route.


Assuntos
Estradiol/administração & dosagem , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Butadienos/antagonistas & inibidores , Butadienos/farmacologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Creatina Quinase/efeitos dos fármacos , Creatina Quinase/metabolismo , DNA/biossíntese , DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Humanos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Nitrilas/antagonistas & inibidores , Nitrilas/farmacologia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
J Steroid Biochem Mol Biol ; 89-90(1-5): 397-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15225808

RESUMO

In cultured human vascular smooth muscle cells (VSMC), estradiol-17beta (E2) induced a biphasic effect on DNA synthesis, i.e., stimulation at low concentrations and inhibition at high concentrations. Additionally, E2 increased the specific activity of creatine kinase (CK) in these cells. Observations that novel protein-bound membrane impermeant estrogenic complexes could elicit inhibition of DNA synthesis, suggested interaction via membranal binding sites. Nevertheless other effects, such as increasing CK activity were only seen with native E2 but not with E2-BSA, thus indicating that the classical nuclear receptor pathway was involved. In the present report, we confirm that human VSMC express both ERalpha and ERbeta. Further, pretreatment of cultured VSMC with the Vitamin D non-calcemic analog JK 1624 F2-2 (JKF) increased ERalpha mRNA (100-200%) but decreased ERbeta mRNA (30-40%) expression as measured by real time PCR. ERalpha protein expression assessed by Western blot analysis increased (25-50%) in parallel, whereas ERbeta protein expression declines (25-55%). Using ovalbumin bound to E2 (Ov-E2) linked to Eu (Eu-Ov-E2), to assess specific membrane binding sites, we observed that membranal binding was down regulated by JKF by 70-80%. In contrast, total cell binding of 3[H] E2, that nearly entirely represents intracellular E2 binding, was increased by 60-100% by the same Vitamin D analog. The results provide evidence that the effects of JKF on ERalpha/ERbeta as well as on membranal versus nuclear binding of estrogen are divergent and show differential modulation.


Assuntos
Calcitriol/análogos & derivados , Calcitriol/farmacologia , Músculo Liso Vascular/metabolismo , Receptores de Estrogênio/metabolismo , Células Cultivadas , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Humanos , Músculo Liso Vascular/citologia , RNA Mensageiro/genética , Receptores de Estrogênio/genética
10.
J Steroid Biochem Mol Biol ; 89-90(1-5): 393-5, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15225807

RESUMO

Estradiol17beta (E2) and the phytoestrogens genistein (G), and daidzein (D) increase creatine kinase (CK) specific activity in primary cell cultures of human female to a greater extent in cells from pre-menopausal than post-menopausal women. Pretreatment with the non-calcemic analog of Vitamin D, JK 1624 F2-2 (JKF), upregulated this estrogenic response at all ages. In contrast, biochainin A (BA) and quercertin (Qu) increased CK with no age dependence or modulation by JKF pretreatment. Both ERalpha and ERbeta present in the cells were upregulated by pretreatment with JKF, as measured by Western blot analysis. Real time PCR showed no significant change in ERalpha mRNA but a marked decrease in ERbeta mRNA in both age groups after JKF treatment. Cells from both age groups had surface binding sites for E2, shown by assays using cell impermeable Europium labeled ovalbumin-E2 conjugate (Eu-Ov-E2). Binding of [3H]-E2 to intracellular E2 receptors (ERs) was similar in both age groups with differences in phytoestrogenic competition. JKF pretreatment increased nuclear but decreased membranal binding in both age groups. These results provide evidence for membranal, in addition to nuclear estrogen receptors which are differentially modulated by a Vitamin D analog.


Assuntos
Osso e Ossos/fisiologia , Estrogênios/fisiologia , Western Blotting , Osso e Ossos/citologia , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Estrogênios/metabolismo , Feminino , Humanos , Ligação Proteica , Receptores de Estrogênio/metabolismo
11.
J Steroid Biochem Mol Biol ; 132(3-5): 256-61, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22776298

RESUMO

Currently available treatments for patients with medullary thyroid carcinoma (MTC) with residual or recurrent disease after primary surgery have low efficacy rates. In view of the possible role of estrogen in the development of thyroid neoplasia, we explored whether proliferation of the human MTC TT cell line, might be curbed by carboxy-daidzein-tBoc (cD-tBoc), a novel isoflavone derivative. Estrogen receptor (ER) α mRNA expression in TT cells was more abundant than ERß, with a ratio of 48:1. Estradiol-17ß (E2) increased DNA synthesis in a dose dependent manner. [(3)H]-thymidine incorporation was also stimulated by the ERß agonist DPN and the ERα agonist PPT. cD-tBoc inhibited TT cell growth as assessed by thymidine incorporation, XTT assay, and microscopic analysis of culture wells. Creatine kinase specific activity, a marker of the modulatory effects of estrogen on cell energy metabolism, was likewise inhibited. The inhibitory effect of cD-tBoc on [(3)H]-thymidine incorporation could be blocked by the ERß antagonist PTHPP but not by the ERα antagonist MPP, suggesting that the antiproliferative effect of cD-tBoc on these cells is mediated through ERß. Furthermore, cD-tBoc potently increased apoptosis and cell necrosis. Co-incubation with the antiapoptotic agent Z-VAD-FMK reversed the growth inhibitory effect elicited by cD-tBoc. These results support the hypothesis that estrogens are involved in the proliferation of MTC. The potent anti-proliferative effects mediated by isoflavone derivatives in the human MTC cell line TT suggest and that this property may be utilized to design effective anti-neoplastic agents.


Assuntos
Antineoplásicos/farmacologia , Isoflavonas/química , Neoplasias da Glândula Tireoide/tratamento farmacológico , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Carcinoma Neuroendócrino , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Creatina Quinase/antagonistas & inibidores , Creatina Quinase/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/genética , Humanos , Isoflavonas/farmacologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia
12.
Neuroendocrinology ; 77(5): 291-7, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12806174

RESUMO

Previous studies have indicated that arachidonic acid and its lipoxygenase (LO) metabolites play a role in the post-receptor effects of gonadotropin-releasing hormone (GnRH) but the exact role and nature of these putative eicosanoids remain unclear. The potential role of arachidonic acid and LO in GnRH receptor-mediated signaling was investigated in the LbetaT2 gonadotrope cell line, which expresses gonadotropins (LH and FSH) and GnRH-receptor mRNAs. Western immunobloting of LbetaT2 cell extracts, performed with a murine leukocyte polyclonal antibody against 12-LO, showed a 70-kD band, suggesting the presence of 12-LO protein in these cells. GnRH nearly doubled the release of 12-hydroeicosatetraenoic acid, a product of the 12-LO enzyme, within 10 min. A specific reverse transcriptase polymerase chain reaction with a set of primers based on the reported sequence of rat brain 12-LO yielded a 170-bp band which showed 100% homology with the expected rat brain 12-LO sequence. Exposure of LbetaT2 cells to pulsatile GnRH treatment (10 nM, 90-min interpulse, one and three pulses) led to a approximately 3-fold increase in 12-LO mRNA levels. In conclusion, we provide evidence for the presence of a 12-LO enzyme in LbetaT2 cells, the expression and activity of which are increased by short-term/pulsatile exposure to GnRH. LbetaT2 cells represent a potential model to further study the involvement of 12-LO in GnRH receptor signaling.


Assuntos
Araquidonato 12-Lipoxigenase/biossíntese , Hormônio Liberador de Gonadotropina/fisiologia , Adeno-Hipófise/enzimologia , Animais , Sequência de Bases , Western Blotting , Indução Enzimática , Regulação da Expressão Gênica/fisiologia , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Adeno-Hipófise/citologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Células Tumorais Cultivadas
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa