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1.
N Z Vet J ; 72(1): 45-52, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37752886

RESUMO

CASE HISTORY: Necropsies on Toggenburg goats culled from a small farm in the Manawatu district of New Zealand, performed at Massey University (Palmerston North, NZ) over a period of 29 years (1991-2019), revealed soft tissue mineralisation, particularly of cardiovascular tissues. The farm spans 10 acres and runs between 15 and 30 Toggenburg goats. The goats are predominantly on pasture comprising a variety of types. PATHOLOGICAL FINDINGS: Necropsies were performed on all adult goats (n = 45) that died or were euthanised. Histopathology was performed on 42 goats (93%), of which 33 (73%) included sufficient tissues diagnostically relevant to soft tissue mineralisation. The most significant gross findings were in various arteries, with the aorta most commonly affected, followed by the heart and lungs. The aortic intima showed prominent, multifocal to coalescing, raised, wrinkled, white plaques. Microscopically there were multiphasic lesions of mineralisation, chondroid, and osseous metaplasia in the elastic arteries, aorta, heart and lungs. A lumbar vertebra from one goat had prominent, basophilic, fibrillar, tangled matrix lining Haversian canals and lamellae. LABORATORY FINDINGS: Blood samples were collected from 15 adult goats in the affected herd and from 10 adult Toggenburg goats from an unaffected herd. Samples were collected by jugular venipuncture at 2-month intervals for 12 months (April 2018-March 2019). Concentrations of calcium, phosphorus, 25-hydroxyvitamin D2 and D3 (25OHD2, 25OHD3) in serum were analysed. The concentration of total 25OHD in serum was 34.2 (95% CI = 18.9-49.4) nmol/L (p < 0.001) higher in goats from the affected herd than in goats from the unaffected herd. Serum 25OHD2 concentration was 46.2 (95% CI = 39.2-53.2) nmol/L higher (p < 0.001) in goats from the affected herd compared to the unaffected herd. Serum Ca concentrations in affected goats were 0.101 (95% CI = 0.005-0.196) mmol/L higher (p = 0.039) than unaffected goats, but remained within the reference range. There was no evidence of a difference in serum 25OHD3 and P concentration between the herds. VEGETATION SURVEY: All paddocks on the property were surveyed every 2 months along evenly spaced line transects, and then further traversed perpendicularly to form a grid. No known calcinogenic species were identified. Known plant sources of vitamin D identified on the farm included mushrooms (species not defined), Dactylis glomerata, lichen, pine pollen, and algae. DIAGNOSIS: Soft tissue mineralisation and enzootic calcinosis. CLINICAL RELEVANCE: Veterinarians are alerted to the possibility of either enzootic calcinosis in goats and the potential occurrence of calcinogenic plants in New Zealand; or chronic vitamin D toxicosis of non-plant origin.


Assuntos
Calcinose , Doenças das Cabras , Humanos , Animais , Nova Zelândia/epidemiologia , Vitamina D , Calcifediol , Calcinose/patologia , Calcinose/veterinária , Cabras , Doenças das Cabras/epidemiologia
3.
Genes Immun ; 16(5): 356-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25906252

RESUMO

Epithelium-specific Ets transcription factor 1 (ESE-1) is a member of the E26 transformation-specific family of transcription factors that has an epithelial-restricted constitutive expression but is induced by inflammatory stimuli in non-epithelial cells. Here we report that ESE-1 is constitutively expressed in human, but not in murine, neutrophils and that ESE-1 is modestly upregulated in septic patient neutrophils. In normal human neutrophils, ESE-1 was detected at both RNA and protein levels but was found to be an unstable nuclear protein ex vivo. ESE-1 transcription was also induced during all-trans retinoic acid-mediated HL-60 differentiation, a human promyelocytic cell line often used as an in vitro model of human neutrophils. Elf3-/- mice had normal neutrophils but a reduced number of circulating B-lymphocytes. These findings indicate a potential role of ESE-1 in regulating human neutrophil differentiation and function, and that it has different roles in the immune system of different species.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Leucopoese , Neutrófilos/metabolismo , Proteínas Proto-Oncogênicas c-ets/metabolismo , Fatores de Transcrição/metabolismo , Animais , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Linhagem Celular , Proteínas de Ligação a DNA/genética , Humanos , Camundongos , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-ets/genética , Especificidade da Espécie , Fatores de Transcrição/genética , Tretinoína/farmacologia
4.
Am J Physiol Endocrinol Metab ; 306(11): E1292-304, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24735887

RESUMO

Many patients with hyperandrogenemia are overweight or obese, which exacerbates morbidities associated with polycystic ovary syndrome (PCOS). To examine the ability of testosterone (T) to generate PCOS-like symptoms, monkeys received T or cholesterol (control) implants (n = 6/group) beginning prepubertally. As previously reported, T-treated animals had increased neuroendocrine drive to the reproductive axis [increased luteinizing hormone (LH) pulse frequency] at 5 yr, without remarkable changes in ovarian or metabolic features. To examine the combined effects of T and obesity, at 5.5 yr (human equivalent age: 17 yr), monkeys were placed on a high-calorie, high-fat diet typical of Western cultures [Western style diet (WSD)], which increased body fat from <2% (pre-WSD) to 15-19% (14 mo WSD). By 6 mo on WSD, LH pulse frequency in the controls increased to that of T-treated animals, whereas LH pulse amplitude decreased in both groups and remained low. The numbers of antral follicles present during the early follicular phase increased in both groups on the WSD, but maximal follicular size decreased by 50%. During the late follicular phase, T-treated females had greater numbers of small antral follicles than controls. T-treated monkeys also had lower progesterone during the luteal phase of the menstrual cycle. Although fasting insulin did not vary between groups, T-treated animals had decreased insulin sensitivity after 1 yr on WSD. Thus, while WSD consumption alone led to some features characteristic of PCOS, T + WSD caused a more severe phenotype with regard to insulin insensitivity, increased numbers of antral follicles at midcycle, and decreased circulating luteal phase progesterone levels.


Assuntos
Adiposidade/fisiologia , Hiperandrogenismo/fisiopatologia , Metabolismo/fisiologia , Reprodução/fisiologia , Absorciometria de Fóton , Envelhecimento/fisiologia , Animais , Peso Corporal/fisiologia , Colesterol/administração & dosagem , Colesterol/farmacologia , Dieta Hiperlipídica , Implantes de Medicamento , Ensaio de Imunoadsorção Enzimática , Feminino , Teste de Tolerância a Glucose , Hormônio Liberador de Gonadotropina/sangue , Hiperandrogenismo/complicações , Hormônio Luteinizante/sangue , Macaca mulatta , Atividade Motora , Sistemas Neurossecretores/fisiologia , Ovário/anatomia & histologia , Ovário/fisiologia , Testosterona/sangue , Testosterona/deficiência , Testosterona/farmacologia
5.
Eye (Lond) ; 27(1): 92-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23154488

RESUMO

PURPOSE: Our aim was to evaluate the potential effect of imatinib mesylate (IM), a small molecule that specifically inhibits the tyrosine quinase receptors, on the proliferation and invasive abilities of two human retinoblastoma (Rb) cell lines. Furthermore, the ability of IM to radiosensitize Rb cells was evaluated. The potential targets of IM (C-kit, PDGRF-α and -ß, and c-Abl) were also investigated in these cell lines. METHODS: Two human Rb cell lines (WERI-RB-1 and Y79) were cultured under normal growth conditions. An MTT-based proliferation assay and a Matrigel invasion assay were performed with and without exposure to 10 µM of IM. The cells were also irradiated with graded dosages of 0, 2, 4, 6, 8, and 10 Gy with and without IM and their proliferations rates were analyzed. Western blot and immunocytochemical analysis of cytospins were performed to evaluate the expression of C-kit, PDGRF-α and -ß, and c-Abl. RESULTS: When IM was added to both cell lines a statistically significant (P<0.05) reduction in proliferation and invasive ability were observed. Exposure to IM also significantly increased the radiosensitivity of both Rb cell lines. The c-Abl expression was strongly positive, PDGRF-α and -ß expression were also positive but the C-kit expression was negative in both cell lines. CONCLUSIONS: These results indicate that Gleevec may be useful as an adjuvant treatment in Rb patients, specially those considered for radiation therapy.


Assuntos
Antineoplásicos/farmacologia , Benzamidas/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Neoplasias da Retina/tratamento farmacológico , Retinoblastoma/tratamento farmacológico , Western Blotting , Linhagem Celular Tumoral/metabolismo , Linhagem Celular Tumoral/efeitos da radiação , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta à Radiação , Humanos , Mesilato de Imatinib , Imuno-Histoquímica , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-kit/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Neoplasias da Retina/metabolismo , Retinoblastoma/metabolismo
6.
Hum Reprod ; 27(2): 531-40, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22114112

RESUMO

BACKGROUND: Hyperandrogenemia is associated with several clinical disorders in which both reproductive dysfunction and metabolic changes may coexist [i.e. polycystic ovary syndrome (PCOS), obesity and congenital adrenal hyperplasia]. Moreover, there is growing evidence that the elevated levels of circulating androgens in obese girls may lead to an increased neuroendocrine drive to the reproductive axis, similar to that associated with PCOS. METHODS: To test whether androgen exposure in the childhood and adolescent period could lead to pubertal alterations in LH secretory patterns, female rhesus monkeys received subcutaneous testosterone implants prepubertally beginning at 1 year of age, maintaining a 3.7-fold increase (P = 0.001) in circulating testosterone levels over cholesterol-implant controls (n = 6/group) into the post-pubertal period. In early adulthood, pulsatile secretion of LH was measured over 12 h during the early follicular phase of a menstrual cycle, and responsiveness of the pituitary to gonadotrophin-releasing hormone was determined. In addition, ultrasounds were performed to assess ovarian morphology and glucose tolerance testing was performed to assess insulin sensitivity. RESULTS: The timing of menarche was similar between groups. Testosterone-treated animals had a significantly greater LH pulse frequency during the early follicular phase compared with controls (P = 0.039) when measured at 5 years of age. There was a larger LH response to GnRH when testosterone-treated animals were 4 years of age (P = 0.042), but not when the animals were 5 years old (P = 0.57). No differences were seen in insulin sensitivity or ovarian morphology, and the groups showed similar rates of ovulation in early adulthood. CONCLUSIONS: Exposure to increased levels of androgens over the course of pubertal development appears to trigger physiological changes in the neural drive to the reproductive axis that resemble those of obese hyperandrogenemic girls in early adulthood and are characteristic of PCOS.


Assuntos
Modelos Animais de Doenças , Glândulas Endócrinas/inervação , Genitália Feminina/inervação , Hiperandrogenismo/fisiopatologia , Sistemas Neurossecretores , Síndrome do Ovário Policístico/etiologia , Maturidade Sexual , Androgênios/administração & dosagem , Androgênios/efeitos adversos , Androgênios/sangue , Animais , Glândulas Endócrinas/efeitos dos fármacos , Glândulas Endócrinas/crescimento & desenvolvimento , Feminino , Genitália Feminina/efeitos dos fármacos , Genitália Feminina/crescimento & desenvolvimento , Hormônio Liberador de Gonadotropina/metabolismo , Resistência à Insulina , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Macaca mulatta , Menarca/efeitos dos fármacos , Ciclo Menstrual/sangue , Sistemas Neurossecretores/efeitos dos fármacos , Sistemas Neurossecretores/crescimento & desenvolvimento , Obesidade/fisiopatologia , Ovário/diagnóstico por imagem , Ovário/crescimento & desenvolvimento , Ovulação/efeitos dos fármacos , Hipófise/crescimento & desenvolvimento , Hipófise/metabolismo , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/metabolismo , Maturidade Sexual/efeitos dos fármacos , Testosterona/administração & dosagem , Testosterona/efeitos adversos , Testosterona/sangue , Ultrassonografia
8.
Eye (Lond) ; 22(5): 707-11, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18219339

RESUMO

PURPOSE: Uveal melanoma (UM) is the most common primary malignant intraocular tumour in adults. Forty-five percent of UM patients develop metastasis within 15 years of initial diagnosis. KISS1, a human metastasis suppressor gene, has been reported to play a role in various human malignancies. The purpose of this study was to investigate the expression of KISS1 in UM and its potential value as a prognostic marker. METHODS: Thirty-seven cases of paraffin-embedded human UM specimens were immunostained with a KISS1 antibody. Clinical-pathological data were obtained. The relationship between the clinical-pathological data and the expression of KISS1 was evaluated. Moreover, the survival rates of the patients were also assessed. Five UM cell lines (92.1, OCM-1, MKTBR, UW1 and SP6.5) were assayed for KISS1 expression. In addition, real-time PCR was used to determine mRNA levels of KISS1and its receptor GPR54in these cell lines. RESULTS: The immunohistochemical results of KISS1 expression displayed cytoplasmic staining in 84% of UM specimens. Low KISS1 expression was associated with a higher risk of metastatic disease (P<0.05). Furthermore, we found that KISS1 was expressed in all five UM cells lines. Real-time PCR analysis confirmed the presence of both KISS1and its receptor GPR54in all five human UM cell lines. CONCLUSIONS: To the best of our knowledge, this is the first time that KISS1has been characterized in UM. The correlation between KISS1 expression and UM survival rate suggests an important role for KISS1as a prognostic marker in this particular tumour.


Assuntos
Biomarcadores Tumorais/análise , Regulação Neoplásica da Expressão Gênica , Melanoma/genética , Proteínas Supressoras de Tumor/análise , Neoplasias Uveais/genética , Biomarcadores Tumorais/genética , Humanos , Imuno-Histoquímica , Kisspeptinas , Melanoma/metabolismo , Melanoma/patologia , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Proteínas Supressoras de Tumor/genética , Neoplasias Uveais/metabolismo , Neoplasias Uveais/patologia
9.
Endocrinology ; 149(1): 139-45, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17932215

RESUMO

We investigated whether Jun N-terminal kinase (JNK) and p38 mediate gonadotropin subunit transcriptional responses to pulsatile GnRH in normal rat pituitaries. A single pulse of GnRH or vehicle was given to female rats in vivo, pituitaries collected, and phosphorylated JNK and p38 measured. GnRH stimulated an increase in JNK phosphorylation within 5 min, which peaked 15 min after GnRH (3-fold). GnRH also increased p38 phosphorylation 2.3-fold 15 min after stimulus. Rat pituitary cells were given 60-min pulses of GnRH or media plus the JNK inhibitor SP600125 (SP, 20 microM), p38 inhibitor SB203580 (20 microM), or vehicle. In vehicle-treated groups, GnRH pulses increased LHbeta and FSHbeta primary transcript (PT) levels 3-fold. SP suppressed both basal and GnRH-induced increases in FSHbeta PT by half, but the magnitude of responses to GnRH was unchanged. In contrast, SP had no effect on basal LHbeta PT but suppressed the stimulatory response to GnRH. SB203580 had no effect on the actions of GnRH on either LH or FSHbeta PTs. Lbeta-T2 cells were transfected with dominant/negative expression vectors for MAPK kinase (MKK)-4 and/or MKK-7 plus a rat LHbeta promoter-luciferase construct. GnRH stimulated a 50-fold increase in LHbeta promoter activity, and the combination of MKK-4 and -7 dominant/negatives suppressed the response by 80%. Thus, JNK (but not p38) regulates both LHbeta and FSHbeta transcription in a differential manner. For LHbeta, JNK is essential in mediating responses to pulsatile GnRH. JNK also regulates FSHbeta transcription (i.e. maintaining basal expression) but does not play a role in responses to GnRH.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Gonadotropinas/genética , Proteínas Quinases JNK Ativadas por Mitógeno/fisiologia , Hipófise/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia , Animais , Células Cultivadas , Masculino , Periodicidade , Fosforilação/efeitos dos fármacos , Hipófise/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacos , Subunidades Proteicas/genética , Ratos , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos
10.
Eye (Lond) ; 22(5): 701-6, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18049486

RESUMO

PURPOSE: To evaluate the proliferation rates of five human uveal melanoma (UM) cell lines after treatment with amfenac, a cyclooxygenase (COX)-2 inhibitor, and subsequent radiation exposure. METHODS: Five human UM cell lines (92.1, SP6.5, MKT-BR, OCM-1, and UW-1) and one human fibroblast cell line (BJ) were incubated with amfenac. Treated and non-treated cell lines were then exposed to various doses of gammaradiation: 0, 2, 4, 6, and 8 Gy. Sulphorhodamine-B assay was used to assess proliferation rates 48 h post-radiation. RESULTS: Treatment of UM cell lines with amfenac prior to radiation led to a marked reduction in proliferation rates. This difference was statistically significant in all cell lines at every radiation dose (P<0.005), with the exception of 92.1 at 2 Gy (P=0.157). Fibroblasts treated with amfenac showed significantly higher proliferation rates after 2 and 8 Gy, with no significant differences at 0, 4, and 6 Gy. CONCLUSIONS: The radiosensitivity of UM cell lines was increased by the administration of amfenac, the active metabolite of nepafenac. There appears to be a radioprotective effect of amfenac on human fibroblasts. The topical administration of nepafenac may decrease tumour recurrence and radiation-induced complications while broadening the indications for radiotherapy by treating larger tumours.


Assuntos
Proliferação de Células , Inibidores de Ciclo-Oxigenase 2/farmacologia , Melanoma/patologia , Fenilacetatos/farmacologia , Radiossensibilizantes/farmacologia , Neoplasias Uveais/patologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Humanos , Melanoma/radioterapia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/efeitos da radiação , Neoplasias Uveais/radioterapia
11.
Hum Reprod Update ; 12(4): 351-61, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16670102

RESUMO

Polycystic ovary syndrome (PCOS) is a common clinical disorder characterized by ovulatory dysfunction and hyperandrogenaemia. A neuroendocrine hallmark of PCOS is persistently rapid LH (GnRH) pulsatility, which favours pituitary synthesis of LH over that of FSH and contributes to the increased LH concentrations and LH : FSH ratios typical of PCOS. Inadequate FSH levels contribute to impaired follicular development, whereas elevated LH levels augment ovarian androgen production. Whereas luteal phase elevations in progesterone normally slow GnRH pulse frequency, women with PCOS do not experience normal progesterone-mediated slowing, due in part to impaired hypothalamic progesterone sensitivity. This reduction in hypothalamic progesterone sensitivity appears to be mediated by elevated androgens because sensitivity can be restored with the androgen receptor blocker flutamide. The ovulatory and hormonal abnormalities associated with PCOS generally present during puberty, typically associated with hyperandrogenaemia. Along with elevated LH concentration and pulsatility, some girls with hyperandrogenaemia have impaired hypothalamic progesterone sensitivity similar to that seen in adult women with PCOS. We propose that peripubertal hyperandrogenaemia may lead to persistently rapid GnRH pulse frequency via impaired hypothalamic feedback inhibition. The subsequent abnormalities in gonadotropin secretion, androgen production and ovulatory function may support progression towards the adult PCOS phenotype.


Assuntos
Sistemas Neurossecretores/fisiopatologia , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/fisiopatologia , Adolescente , Androgênios , Estrogênios/metabolismo , Feminino , Hormônio Foliculoestimulante/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Humanos , Hiperandrogenismo/metabolismo , Insulina/metabolismo , Hormônio Luteinizante/metabolismo , Sistemas Neurossecretores/metabolismo , Ovulação , Síndrome do Ovário Policístico/etiologia , Progesterona , Puberdade/fisiologia , Valores de Referência
12.
Eye (Lond) ; 20(5): 598-601, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16123787

RESUMO

PURPOSE: To examine the effect of nepafenac, a selective cyclooxygenase-2 (COX-2) inhibitor, on the proliferation rate of two human retinoblastoma (Rb)cell lines. METHODS: Two human Rb cell lines (WERI-RB and Y79) were cultured. COX-2 expression in these cell lines was verified by immunocytochemical analysis of cytospin sections and Western blotting. An MTT-based proliferation assay was used to compare Rb cell growth with and without amfenac, the active metabolite of nepafenac. The averaged results per condition were recorded. The Student's t-test was used to compare results from the cells cultured with and without amfenac. RESULT: The Y79 cell line showed a higher proliferative rate than the WERI-RB cell line. Both cell lines were negative for COX-2 expression by immunocytochemical analysis; however, both cell lines were positive for COX-2 expression by Western blot. When amfenac was added to both of the cell lines, a statistically significant reduction in proliferation was observed in both cell lines. The two Rb cell lines were positive for COX-2 only in the Western blot, indicating that they probably express low levels of COX-2, which was undetectable by immunocytochemical analysis. CONCLUSION: The selective, anti-COX-2 molecule amfenac inhibited proliferation of both tested Rb cell lines. Further trials should be undertaken to study the effect of selective COX-2 inhibitors on Rb.


Assuntos
Inibidores de Ciclo-Oxigenase 2/farmacologia , Fenilacetatos/farmacologia , Neoplasias da Retina/patologia , Retinoblastoma/patologia , Western Blotting , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Humanos , Neoplasias da Retina/enzimologia , Retinoblastoma/enzimologia , Células Tumorais Cultivadas
13.
Biol Reprod ; 72(3): 523-9, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15509729

RESUMO

This study investigated whether estradiol (E2) or testosterone (T) activate extracellular signal-regulated kinase (ERK) and calcium/calmodulin-dependent kinase II (Ca/CaMK II), as indicated by enzyme phosphorylation in rat pituitaries. In vivo studies used adult female rats given E2, T, or empty silastic capsules (vehicle controls). Twenty-four hours later, the rats were given a single pulse of GnRH (300 ng) or BSA-saline (to controls) and killed 5 min later. GnRH stimulated a two- to three-fold rise in activated Ca/CaMK II, and E2 and T had no effect on Ca/CaMK II activation. In contrast, both GnRH and T stimulated threefold increases in ERK activity, with additive effects seen following the combination of GnRH+T. E2 had no effect on ERK activity. In alpha T3 clonal gonadotrope cells, dihydrotestosterone did not activate ERK alone but enhanced and prolonged the ERK responses to GnRH, demonstrating direct effects on the gonadotrope. Thus, the ERK response to GnRH plus androgen was enhanced in both rat pituitary and alpha T3 cells. In vitro studies with cultured rat pituitary cells examined the effect of GnRH+/-T in the presence of the mitogen-activated protein (MAP) kinase kinase inhibitor, PD-098059 (PD). Results showed that PD suppressed ERK activational and FSH beta transcriptional responses to T. These findings suggest that one site of T regulation of FSH beta transcription is through the selective stimulation of the ERK pathway.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Subunidade beta do Hormônio Folículoestimulante/metabolismo , Hipófise/enzimologia , Testosterona/fisiologia , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Células Cultivadas , Ativação Enzimática , Estradiol/fisiologia , Feminino , Hormônio Liberador de Gonadotropina/fisiologia , Ovariectomia , Fosforilação , Hipófise/citologia , Ratos , Ativação Transcricional
14.
J Mol Endocrinol ; 33(3): 559-84, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15591020

RESUMO

Reproductive function in mammals is regulated by the pituitary gonadotropins luteinizing hormone (LH) and follicle-stimulating hormone (FSH). LH and FSH are secreted by the gonadotrope cell and act on the gonad in a sequential and synergistic manner to initiate sexual maturation and maintain cyclic reproductive function. The synthesis and secretion of LH and FSH are regulated mainly by the pulsatile release of the hypothalamic decapeptide hormone gonadotropin-releasing hormone (GnRH). The control of differential LH and FSH synthesis and secretion is complex and involves the interplay between the gonads, hypothalamus and pituitary. In this review, the transcriptional regulation of the gonadotropin subunit genes is discussed in a physiologic setting, and we aimed to examine the mechanisms that drive those changes.


Assuntos
Regulação da Expressão Gênica/genética , Gonadotropinas/química , Gonadotropinas/genética , Transcrição Gênica/genética , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Humanos , Subunidades Proteicas/genética , Esteroides/farmacologia
15.
Endocrinology ; 144(7): 2768-74, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12810529

RESUMO

The intracellular pathways mediating GnRH regulation of gonadotropin subunit transcription remain to be fully characterized, and the present study examined whether calcium/calmodulin-dependent kinase II (Ca/CAMK II) plays a role in the rat pituitary. Preliminary studies demonstrated that a single pulse of GnRH given to adult rats stimulated a transient 2.5-fold rise in Ca/CAMK II activity (as determined by an increase in Ca/CAMK II phosphorylation), with peak values at 5 min, returning to basal 45 min after the pulse. Further studies examined the alpha, LHbeta, and FSHbeta transcriptional responses to GnRH or Bay K 8644+KCl (BK+KCl) pulses in vitro in the absence or presence of the Ca/CAMK II-specific inhibitor, KN-93. Gonadotropin subunit transcription was assessed by measuring primary transcripts (PTs) by quantitative RT-PCR. In time-course studies, both GnRH and BK+KCl pulses given alone increased all three subunit PTs after 6 h (2- to 4-fold). PT responses to GnRH increased over time (3- to 8-fold over basal at 24 h), although BK+KCl was ineffective after 24 h. KN-93 reduced the LHbeta and FSHbeta transcriptional responses to GnRH by 50-60% and completely suppressed the alphaPT response. In contrast, KN-93 showed no inhibitory effects on basal transcriptional activity or LH or FSH secretion. In fact, KN-93 tended to increase basal alpha, LHbeta, and FSHbeta PT levels and enhance LH secretory responses to GnRH. These results reveal that Ca/CAMK II plays a central role in the transmission of pulsatile GnRH signals from the plasma membrane to the rat alpha, LHbeta, and FSHbeta subunit genes.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Hormônio Liberador de Gonadotropina/farmacologia , Gonadotropinas/genética , Hipófise/enzimologia , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Feminino , Subunidade beta do Hormônio Folículoestimulante/genética , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Subunidade alfa de Hormônios Glicoproteicos/genética , Hormônio Luteinizante Subunidade beta/genética , Masculino , Hipófise/efeitos dos fármacos , Fluxo Pulsátil/fisiologia , Ratos , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/fisiologia
16.
Shock ; 16(5): 361-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11699074

RESUMO

Through their effects on gene activation, antioxidants have been reported to modulate cellular expression of several proinflammatory cytokines and adhesion molecules, an effect mediated by preventing translocation of the transcription factor nuclear factor-kappa B (NF-kappa B) into the nucleus. In addition, modulation of the intracellular redox state may have profound effects on cell activation and subsequent gene expression distinct from effects on NF-kappa B; these effects may account for the divergent effects of antioxidants on cytokine gene expression in various reports. In the present studies, we evaluated the effect of the antioxidant, pyrrolidine dithiocarbamate (PDTC), on murine and human myeloid cell tumor necrosis factor alpha (TNF alpha) gene and protein expression. PDTC-enhanced LPS-induced TNF alpha secretion in cells derived from a murine macrophage cell line (J774.1), as well as in primary murine peritoneal macrophages by 4-fold. The effect was both stimulus and species dependent, as TNF alpha secretion was attenuated by PDTC in human THP-1 cells and in murine cells stimulated with zymosan. Northern analysis demonstrated that these effects were evident at the level of mRNA expression. Electrophoretic mobility shift assays confirmed the down-regulatory effect of PDTC on human myeloid NF-kappa B activation, whereas in murine cells no such inhibitory effect was evident. Evaluation of TNF alpha mRNA stability in murine cells demonstrated that the potentiating effect of PDTC on TNF alpha mRNA expression was due to an increase in mRNA half-life from 37 to 93 min. Together, these data suggest that the effect of antioxidants on gene expression are both stimulus and species dependent and illustrate a novel mechanism whereby redox manipulation might modulate TNF alpha expression in vivo.


Assuntos
Antioxidantes/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/imunologia , Prolina/análogos & derivados , Prolina/farmacologia , RNA Mensageiro/metabolismo , Tiocarbamatos/farmacologia , Transcrição Gênica/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Sinergismo Farmacológico , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Cinética , Macrófagos/efeitos dos fármacos , Camundongos , Ativação Transcricional
17.
Biol Reprod ; 65(6): 1789-93, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11717142

RESUMO

Alterations in the frequency of calcium influx signals to rat pituitary cells can regulate the expression of gonadotropin subunit mRNAs in a differential manner, producing effects that are similar to those previously found for GnRH. The present study was conducted to investigate whether this reflects a transcriptional response to calcium pulse frequency, as determined by alterations in primary transcript (PT) expression. Perifused rat pituitary cells were given pulses of the calcium channel-activator Bay K 8644 (BK; with 10 mM KCl in the injectate) for 6 h. The response to alterations in pulse dose was examined by giving pulses of 1, 3, or 10 microM BK at 60-min intervals. Maximal increases in LHbeta and FSHbeta PTs were obtained with the 3-microM BK pulse dose and with the 10-microM dose for alpha. To investigate the effect of calcium pulse frequency, 3-microM BK pulses were given at intervals of 15, 60, or 180 min. Alpha PT was selectively stimulated by 15-min pulses and LHbeta by 15- and 60-min pulses of BK. In contrast, FSHbeta PT was maximally stimulated by the slower, 180-min pulse interval. These findings reveal that pulsatile increases in intracellular calcium stimulate alpha, LHbeta, and FSHbeta transcription in a differential manner. Thus, intermittent changes in intracellular calcium appear to be important in the transmission of GnRH pulse signals from the plasma membrane to the gene, and they may mediate the differential actions of pulse frequency on gonadotropin subunit gene expression.


Assuntos
Cálcio/metabolismo , Hormônio Foliculoestimulante/genética , Regulação da Expressão Gênica , Hormônio Luteinizante/genética , Hipófise/metabolismo , Transdução de Sinais , Éster Metílico do Ácido 3-Piridinacarboxílico, 1,4-Di-Hidro-2,6-Dimetil-5-Nitro-4-(2-(Trifluormetil)fenil)/administração & dosagem , Éster Metílico do Ácido 3-Piridinacarboxílico, 1,4-Di-Hidro-2,6-Dimetil-5-Nitro-4-(2-(Trifluormetil)fenil)/farmacologia , Animais , Cálcio/farmacologia , Agonistas dos Canais de Cálcio/administração & dosagem , Agonistas dos Canais de Cálcio/farmacologia , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/fisiologia , Feminino , Hormônio Foliculoestimulante/metabolismo , Subunidade beta do Hormônio Folículoestimulante , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Luteinizante/metabolismo , Periodicidade , Cloreto de Potássio/farmacologia , RNA Mensageiro/análise , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica
18.
Mol Cell Endocrinol ; 183(1-2): 29-32, 2001 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-11604221

RESUMO

A pulsatile GnRH stimulus is required to maintain gonadotropin synthesis and secretion. The frequency and amplitude of GnRH pulses determine gonadotropin subunit gene expression and secretion of pituitary LH and FSH. Rapid frequency (more than 1 pulse per h) GnRH pulses favor LH while slower frequencies favor FSH secretion. During ovulatory cycles, an increase in GnRH frequency during the follicular phase favors LH synthesis prior to the LH surge, while following ovulation, luteal steroids slow GnRH pulses to favor FSH synthesis. Thus, a changing frequency of GnRH stimulation of the gonadotrope is one of the mechanisms involved in differential gonadotropin secretion during ovulatory cycles. In hypothalamic amenorrhea a majority of women exhibit a persistent slow frequency of LH (GnRH) pulses, which reflects excess hypothalamic opioid tone and can be temporarily reversed by opioid antagonists. At the other end of the spectrum, in polycystic ovarian syndrome, LH (GnRH) pulses are persistently rapid and favor LH synthesis, hyperandrogenism and impaired follicular maturation. Administration of progesterone can slow GnRH pulse secretion, favor FSH secretion and induce follicular maturation. Thus, the ability to change the pattern of GnRH secretion is an important factor in the maintenance of cyclic ovulation, and loss of this function leads to anovulation and amenorrhea.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/fisiopatologia , Hormônio Luteinizante/metabolismo , Amenorreia/fisiopatologia , Animais , Ciclo Estral/fisiologia , Feminino , Humanos , Síndrome de Kallmann/fisiopatologia , Ciclo Menstrual/fisiologia , Síndrome do Ovário Policístico/fisiopatologia , Prolactina/sangue , Fatores de Tempo
19.
Surgery ; 130(2): 157-65, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11490344

RESUMO

BACKGROUND: Liver injury after ischemia/reperfusion is an important cause of morbidity in surgical patients. We have shown that the preconditioning of animals that were subjected to liver ischemia/reperfusion with hypertonic saline solution (HTS) prevented injury by inhibiting Kupffer cell tumor necrosis factor (TNF) production. We postulated that the induction of anti-inflammatory interleukin-10 (IL-10) by HTS might contribute to protection. METHODS: Murine thioglycolate--elicited peritoneal exudative macrophages (PEMs) were used to model the effects of HTS on IL-10 release from Kupffer cells. Cells were preconditioned with 500 mOsm HTS (or isotonic saline medium) for 2 hours and then stimulated with lipopolysaccharide (LPS; 1 microg/mL) or vehicle for 4 hours under isotonic conditions. TNF-alpha and IL-10 were measured in the culture supernatant by enzyme-linked immunosorbent assay; TNF, IL-10, and SOCS-3 messenger RNA expression were assessed by Northern blot. NF-kappa B activation was examined by electrophoretic mobility shift assay and Western blot for I kappa B degradation. RESULTS: In the absence of LPS, isotonic medium--and HTS-pretreated PEMs produced little IL-10 (24.9 +/- 66.0 and 0 pg/mL, respectively); however, stimulation of PEMs with LPS increased IL-10 (134.9 +/- 72.2 pg/mL). Preconditioning with HTS significantly augmented LPS-induced IL-10 production, resulting in a 2-fold increase in IL-10 compared with the isotonic solution LPS group (270.7 +/- 106.8 pg/mL; P <.01). HTS alone increased IL-10 mRNA levels and markedly augmented levels induced by LPS alone. To determine whether IL-10 accounted for HTS-induced TNF inhibition, cells from IL-10 knockout animals were studied. A lack of IL-10 did not reverse the inhibitory effect of HTS on LPS-induced TNF. NF-kappa B activation was the same in HTS-and isotonic solution--pretreated groups after LPS. CONCLUSIONS: HTS augments IL-10 induction by LPS at the gene level. Although TNF is reduced, it is not causally related to increased IL-10 or altered NF-kappa B signaling. HTS might exert its beneficial effects by independently modulating pro- and anti-inflammatory molecules, accounting for the potent immunomodulation exerted by HTS in vivo.


Assuntos
Interleucina-10/genética , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/metabolismo , Proteínas Repressoras , Solução Salina Hipertônica/farmacologia , Fatores de Transcrição , Animais , Sinergismo Farmacológico , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Interleucina-10/análise , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteínas/genética , RNA Mensageiro/análise , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/genética
20.
Endocrinology ; 142(8): 3435-42, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11459788

RESUMO

The aim of this study was to determine if the changes in gonadotropin subunit gene expression following ovariectomy reflect transcriptional and/or posttranscriptional regulation by GnRH or inhibin. Subunit transcription rates were determined by recently developed quantitative RT-PCR for subunit primary transcripts (as an indicator of gene transcription), which allow us to measure both mRNA and PT from RNA extracted from a single pituitary. Following ovariectomy, LHbeta PT concentrations increased 2- to 3-fold between 72 h and 7 d, paralleling changes in serum LH and LHbeta mRNA. In contrast, serum FSH, FSHbeta mRNA, and FSHbeta PT concentrations were 6- to 9-fold greater 12-24 h after ovariectomy followed by an additional 2.5-fold increase at 72 h. Although alpha RNA was elevated at 72 h after ovariectomy, alpha-primary transcript did not change. GnRH antagonist prevented the increase in LHbeta-PT at 72 h, but had no effect on the increase in FSHbetaPT at 12 h and was only partially effective at 72 h. The acute GnRH-independent increase in FSHbeta-primary transcript after ovariectomy could be duplicated by the administration of inhibin antiserum to intact rats; inhibin-alpha antiserum did not affect LHbeta-primary transcript, but increased FSHbeta-primary transcript concentrations 8- to 11-fold. The half-disappearance rates of LHbeta and FSHbeta primary transcripts were measured after GnRH blockade or administration of recombinant human inhibin A. The half-disappearance times for LHbeta and FSHbeta primary transcripts following GnRH blockade were 13 and 17 min, respectively; the mRNAs did not change. The effects of inhibin were specific for FSHbeta; 60 min after inhibin FSHbeta-primary transcript was undetectable with a half-disappearance time of 19 min, additionally FSHbeta mRNA levels also fell with a half-life of 94 min. In conclusion, these data support previous evidence that GnRH regulates gonadotropin gene expression primarily at the level of transcription. However, the acute increase in FSHbeta-primary transcript after ovariectomy or immunoneutralization of inhibin-alpha, and the rapid fall in FSHbeta-primary transcript following rh inhibin, provide novel evidence that inhibin suppresses FSHbeta gene transcription in addition to its action in regulating FSHbeta mRNA stability.


Assuntos
Hormônio Foliculoestimulante/genética , Hormônio Luteinizante/genética , Ovário/fisiologia , Transcrição Gênica/fisiologia , Animais , Feminino , Subunidade beta do Hormônio Folículoestimulante , Hormônio Liberador de Gonadotropina/fisiologia , Inibinas/farmacologia , Inibinas/fisiologia , Ovariectomia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes , Transcrição Gênica/efeitos dos fármacos
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