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1.
Reprod Sci ; 30(1): 203-220, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35715551

RESUMO

The intracellular signaling pathways that regulate myometrial contractions can be targeted by drugs for tocolysis. The agents, 2-APB, glycyl-H-1152, and HC-067047, have been identified as inhibitors of uterine contractility and may have tocolytic potential. However, the contraction-blocking potency of these novel tocolytics was yet to be comprehensively assessed and compared to agents that have seen greater scrutiny, such as the phosphodiesterase inhibitors, aminophylline and rolipram, or the clinically used tocolytics, nifedipine and indomethacin. We determined the IC50 concentrations (inhibit 50% of baseline contractility) for 2-APB, glycyl-H-1152, HC-067047, aminophylline, rolipram, nifedipine, and indomethacin against spontaneous ex vivo contractions in pregnant human myometrium, and then compared their tocolytic potency. Myometrial strips obtained from term, not-in-labor women, were treated with cumulative concentrations of the contraction-blocking agents. Comprehensive dose-response curves were generated. The IC50 concentrations were 53 µM for 2-APB, 18.2 µM for glycyl-H-1152, 48 µM for HC-067047, 318.5 µM for aminophylline, 4.3 µM for rolipram, 10 nM for nifedipine, and 59.5 µM for indomethacin. A single treatment with each drug at the determined IC50 concentration was confirmed to reduce contraction performance (AUC) by approximately 50%. Of the three novel tocolytics examined, glycyl-H-1152 was the most potent inhibitor. However, of all the drugs examined, the overall order of contraction-blocking potency in decreasing order was nifedipine > rolipram > glycyl-H-1152 > HC-067047 > 2-APB > indomethacin > aminophylline. These data provide greater insight into the contraction-blocking properties of some novel tocolytics, with glycyl-H-1152, in particular, emerging as a potential novel tocolytic for preventing preterm birth.


Assuntos
Nascimento Prematuro , Tocolíticos , Recém-Nascido , Gravidez , Humanos , Feminino , Tocolíticos/farmacologia , Nifedipino/farmacologia , Nifedipino/metabolismo , Miométrio/metabolismo , Rolipram/metabolismo , Rolipram/farmacologia , Aminofilina/metabolismo , Aminofilina/farmacologia , Nascimento Prematuro/metabolismo , Contração Uterina , Indometacina/metabolismo , Indometacina/farmacologia
2.
J Comp Physiol B ; 190(1): 49-62, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31858229

RESUMO

Nonapeptides and their receptors regulate a diverse range of physiological processes. We assessed the contractile responsiveness of uteri from the squamate viviparous-oviparous species pair, Pseudemoia entrecasteauxii and Lampropholis guichenoti, as well as the bimodally reproductive species, Saiphos equalis, to arginine vasopressin (AVP). We assessed the resulting uterine contractility as a function of pregnancy status, species and parity mode. We also measured mRNA abundance for the nonapeptide receptor, oxytocin receptor (oxtr), in uteri from P. entrecasteauxii and L. guichenoti and compared expression across pregnancy status and parity mode. We found that pregnant uteri exhibited a significantly greater contractile response to AVP than non-pregnant uteri in all three lizard species studied. Cross-species comparisons revealed that uteri from viviparous P. entrecasteauxii were significantly more responsive to AVP than uteri from oviparous L. guichenoti during both pregnant and non-pregnant states. Conversely, for non-pregnant S. equalis, uteri from viviparous individuals were significantly less responsive to AVP than uteri from oviparous individuals, while during pregnancy, there was no difference in AVP contractile responsiveness. There was no difference in expression of oxtr between L. guichenoti and P. entrecasteauxii, or between pregnant and non-pregnant individuals within each species. We found no significant correlation between oxtr expression and AVP contractile responsiveness. These findings indicate that there are differences in nonapeptide signalling across parity mode and suggest that in these lizards, labour may be triggered either by an increase in plasma nonapeptide concentration, or by an increase in expression of a different nonapeptide receptor from the vasopressin-like receptor family.


Assuntos
Arginina Vasopressina/farmacologia , Lagartos/fisiologia , Oviparidade/fisiologia , Contração Uterina/efeitos dos fármacos , Viviparidade não Mamífera/fisiologia , Sequência de Aminoácidos , Animais , Feminino , Lagartos/embriologia , Lagartos/genética , Lagartos/metabolismo , Oviparidade/efeitos dos fármacos , Ocitocina/metabolismo , Gravidez , Receptores de Ocitocina/genética , Receptores de Ocitocina/metabolismo , Reprodução/efeitos dos fármacos , Homologia de Sequência , Viviparidade não Mamífera/efeitos dos fármacos
3.
Exp Physiol ; 105(4): 555-561, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31856312

RESUMO

NEW FINDINGS: What is the topic of this review? The timing of birth is an important determinant of future health and well-being. This review examines the role of endogenous retroviruses as upstream regulators of key biological functions of the placenta, including cell-cell fusion, modulation of the maternal immune system, and the production of key pregnancy hormones. What advances does it highlight? Endogenous retroviruses are an obligate requirement for successful human reproduction. The products of retroviral elements, incorporated into the germline millions of years ago, have been co-opted to serve vital biological roles within the placenta that ultimately dictate the length of human pregnancy and therefore well-being trajectories. ABSTRACT: Gestational length at the time of birth is an important determinant of future health and well-being, yet the physiological regulation of the onset of labour in humans remains obscure. The evolution of egg formation and internal fertilisation in amniotes required a mechanism to suppress the contractile activity of the oviduct that is provided by progesterone. Delivery of the egg is then associated with the withdrawal of progesterone and a return of contractile activity to the reproductive tract. In mammals, the process of pregnancy is complicated further by the need to protect the fetus from potential attack by the maternal immune system. There is increasing evidence that retroviruses incorporated into the mammalian germline in the evolutionary past play a key role in suppressing the maternal immune reaction to the developing conceptus, organising the development of the placenta and perhaps, in humans, modulating the action of progesterone, determining gestational length and the onset of labour. It seems that the presence of an endogenous retrovirus is an obligate requirement for human reproduction.


Assuntos
Retrovirus Endógenos/fisiologia , Placenta/fisiologia , Reprodução/fisiologia , Animais , Feminino , Humanos , Placenta/metabolismo , Gravidez , Progesterona/metabolismo
4.
Int J Mol Sci ; 20(23)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775361

RESUMO

Metastases in thyroid cancer are associated with aggressive disease and increased patient morbidity, but the factors driving metastatic progression are unclear. The precursor for nerve growth factor (proNGF) is increased in primary thyroid cancers, but its expression or significance in metastases is not known. In this study, we analysed the expression of proNGF in a retrospective cohort of thyroid cancer lymph node metastases (n = 56), linked with corresponding primary tumours, by automated immunohistochemistry and digital quantification. Potential associations of proNGF immunostaining with clinical and pathological parameters were investigated. ProNGF staining intensity (defined by the median h-score) was significantly higher in lymph node metastases (h-score 94, interquartile range (IQR) 50-147) than in corresponding primary tumours (57, IQR 42-84) (p = 0.002). There was a correlation between proNGF expression in primary tumours and corresponding metastases, where there was a 0.68 (95% CI 0 to 1.2) increase in metastatic tumour h-score for each unit increase in the primary tumour h-score. However, larger tumours (both primary and metastatic) had lower proNGF expression. In a multivariate model, proNGF expression in nodal metastases was negatively correlated with lateral neck disease and being male. In conclusion, ProNGF is expressed in locoregional metastases of thyroid cancer and is higher in lymph node metastases than in primary tumours, but is not associated with high-risk clinical features.


Assuntos
Adenocarcinoma Folicular/secundário , Biomarcadores Tumorais/metabolismo , Carcinoma Papilar/secundário , Fator de Crescimento Neural/metabolismo , Precursores de Proteínas/metabolismo , Neoplasias da Glândula Tireoide/patologia , Adenocarcinoma Folicular/metabolismo , Adulto , Idoso , Carcinoma Papilar/metabolismo , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/metabolismo
5.
BMC Endocr Disord ; 19(1): 128, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31775768

RESUMO

BACKGROUND: Nerves and neurotrophic growth factors are emerging promoters of cancer growth. The precursor for Nerve Growth Factor (proNGF) is overexpressed in thyroid cancer, but its potential role as a clinical biomarker has not been reported. Here we have examined the value of proNGF as a serum and biopsy-rinse biomarker for thyroid cancer diagnosis. METHODS: Patients presenting for thyroid surgery or biopsy were enrolled in separate cohorts examining serum (n = 204, including 46 cases of thyroid cancer) and biopsy-rinse specimens (n = 188, including 26 cases of thyroid cancer). ProNGF levels in clinical samples were analysed by ELISA. Univariate and multivariate statistical analyses were used to compare proNGF levels with malignancy status and clinicopathological parameters. RESULTS: ProNGF was not detected in the majority of serum samples (176/204, 86%) and the detection of proNGF was not associated with thyroid cancer diagnosis. In the few cases where proNGF was detected in the serum, thyroidectomy did not affect proNGF concentration, demonstrating that the thyroid was not the source of serum proNGF. Intriguingly, an association between hyperthyroidism and serum proNGF was observed (OR 3.3, 95% CI 1.6-8.7 p = 0.02). In biopsy-rinse, proNGF was detected in 73/188 (39%) cases, with no association between proNGF and thyroid cancer. However, a significant positive association between follicular lesions and biopsy-rinse proNGF was found (OR 3.3, 95% CI 1.2-8.7, p = 0.02). CONCLUSIONS: ProNGF levels in serum and biopsy-rinse are not increased in thyroid cancer and therefore proNGF is not a clinical biomarker for this condition.


Assuntos
Biomarcadores Tumorais/análise , Biópsia , Fator de Crescimento Neural/análise , Fator de Crescimento Neural/sangue , Precursores de Proteínas/análise , Precursores de Proteínas/sangue , Neoplasias da Glândula Tireoide/diagnóstico , Adulto , Idoso , Biomarcadores Tumorais/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia
6.
Biomed Res Int ; 2019: 5214821, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30800670

RESUMO

Densitometry data generated for Western blots are commonly used to compare protein abundance between samples. In the last decade, it has become apparent that assumptions underpinning these comparisons are often violated in studies reporting Western blot data in the literature. These violations can lead to erroneous interpretations of data and may contribute to poor reproducibility of research. We assessed the reliability of Western blot data obtained to study human myometrial tissue proteins. We ran dilution series of protein lysates to explore the linearity of densitometry data. Proteins analysed included αSMA, HSP27, ERK1/2, and GAPDH. While ideal densitometry data are directly proportional to protein abundance, our data confirm that densitometry data often deviate from this ideal, in which case they can fit nonproportional linear or hyperbolic mathematical models and can reach saturation. Nonlinear densitometry data were observed when Western blots were detected using infrared fluorescence or chemiluminescence, and under different SDS-PAGE conditions. We confirm that ghosting artefacts associated with overabundance of proteins of interest in Western blots can skew findings. We also confirm that when data to be normalised are not directly proportional to protein abundance, it is a mistake to use the normalisation technique of dividing densitometry data from the protein-of-interest with densitometry data from loading control protein(s), as this can cause the normalised data to be unusable for making comparisons. Using spiked proteins in a way that allowed us to control the total protein amount per lane, while only changing the amount of spiked proteins, we confirm that nonlinearity and saturation of densitometry data, and errors introduced from normalisation processes, can occur in routine assays that compare equal amounts of lysate. These findings apply to all Western blot studies, and we highlight quality control checks that should be performed to make Western blot data more quantitative.


Assuntos
Western Blotting/métodos , Densitometria/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Humanos , Proteínas/química , Reprodutibilidade dos Testes
7.
Endocr Relat Cancer ; 24(6): R191-R202, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28351942

RESUMO

Recent advances in the arena of theranostics have necessitated a re-examining of previously established fields. The existing paradigm of therapeutic thyroid-stimulating hormone receptor (TSHR) targeting in the post-surgical management of differentiated thyroid cancer using levothyroxine and recombinant human thyroid-stimulating hormone (TSH) is well understood. However, in an era of personalized medicine, and with an increasing awareness of the risk profile of longstanding pharmacological hyperthyroidism, it is imperative clinicians understand the molecular basis and magnitude of benefit for individual patients. Furthermore, TSHR has been recently re-conceived as a selective target for residual metastatic thyroid cancer, with pilot data demonstrating effective targeting of nanoparticles to thyroid cancers using this receptor as a target. This review examines the evidence for TSHR signaling as an oncogenic pathway and assesses the evidence for ongoing TSHR expression in thyroid cancer metastases. Priorities for further research are highlighted.


Assuntos
Receptores da Tireotropina/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Animais , Humanos , Receptores da Tireotropina/antagonistas & inibidores , Receptores da Tireotropina/química , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/patologia
8.
Am J Obstet Gynecol ; 216(3): 283.e1-283.e14, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27567564

RESUMO

BACKGROUND: The ability to provide safe and effective pharmacotherapy during obstetric complications, such as preterm labor or postpartum hemorrhage, is hampered by the systemic toxicity of therapeutic agents leading to adverse side effects in the mother and fetus. Development of novel strategies to target tocolytic and uterotonic agents specifically to uterine myocytes would improve therapeutic efficacy while minimizing the risk of side effects. Ligand-targeted liposomes have emerged as a reliable and versatile platform for targeted drug delivery to specific cell types, tissues or organs. OBJECTIVE: Our objective was to develop a targeted drug delivery system for the uterus utilizing an immunoliposome platform targeting the oxytocin receptor. STUDY DESIGN: We conjugated liposomes to an antibody that recognizes an extracellular domain of the oxytocin receptor. We then examined the ability of oxytocin receptor-targeted liposomes to deliver contraction-blocking (nifedipine, salbutamol and rolipram) or contraction-enhancing (dofetilide) agents to strips of spontaneously contracting myometrial tissue in vitro (human and mouse). We evaluated the ability of oxytocin receptor-targeted liposomes to localize to uterine tissue in vivo, and assessed if targeted liposomes loaded with indomethacin were capable of preventing lipopolysaccharide-induced preterm birth in mice. RESULTS: Oxytocin receptor-targeted liposomes loaded with nifedipine, salbutamol or rolipram consistently abolished human myometrial contractions in vitro, while oxytocin receptor-targeted liposomes loaded with dofetilide increased contraction duration. Nontargeted control liposomes loaded with these agents had no effect. Similar results were observed in mouse uterine strips. Following in vivo administration to pregnant mice, oxytocin receptor-targeted liposomes localized specifically to the uterine horns and mammary tissue. Targeting increased localization to the uterus 7-fold. Localization was not detected in the maternal brain or fetus. Targeted and nontargeted liposomes also localized to the liver. Oxytocin receptor-targeted liposomes loaded with indomethacin were effective in reducing rates of preterm birth in mice, whereas nontargeted liposomes loaded with indomethacin had no effect. CONCLUSION: Our results demonstrate that oxytocin receptor-targeted liposomes can be used to either inhibit or enhance human uterine contractions in vitro. In vivo, the liposomes localized to the uterine tissue of pregnant mice and were effective in delivering agents for the prevention of inflammation-induced preterm labor. The potential clinical advantage of targeted liposomal drug delivery to the myometrium is reduced dose and reduced toxicity to both mother and fetus.


Assuntos
Nascimento Prematuro/prevenção & controle , Receptores de Ocitocina/efeitos dos fármacos , Contração Uterina/efeitos dos fármacos , Útero/efeitos dos fármacos , Albuterol/administração & dosagem , Albuterol/farmacocinética , Animais , Sistemas de Liberação de Medicamentos , Feminino , Indometacina/administração & dosagem , Lipossomos/imunologia , Camundongos , Miométrio/efeitos dos fármacos , Miométrio/metabolismo , Nifedipino/administração & dosagem , Nifedipino/farmacocinética , Fenetilaminas/administração & dosagem , Fenetilaminas/farmacocinética , Gravidez , Rolipram/administração & dosagem , Rolipram/farmacocinética , Sulfonamidas/administração & dosagem , Sulfonamidas/farmacocinética , Distribuição Tecidual , Contração Uterina/imunologia , Útero/imunologia
9.
PLoS One ; 10(4): e0118629, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25831059

RESUMO

BACKGROUND: Pregnancy increases susceptibility to influenza. The placenta releases an immunosuppressive endogenous retroviral protein syncytin-1. We hypothesised that exposure of peripheral monocytes (PBMCs) to syncytin-1 would impair responses to H1N1pdm09 influenza. METHODS AND FINDINGS: Recombinant syncytin-1 was produced. PBMCs from non-pregnant women (n=10) were exposed to H1N1pdm09 in the presence and absence of syncytin-1 and compared to responses of PBMCs from pregnant women (n=12). PBMCs were characterised using flow cytometry, release of interferon (IFN)-α, IFN-λ, IFN-γ, IL-10, IL-2, IL-6 and IL-1ß were measured by cytometric bead array or ELISA. Exposure of PBMCs to H1N1pdm09 resulted in the release of IFN-α, (14,787 pg/mL, 95% CI 7311-22,264 pg/mL) IFN-λ (1486 pg/mL, 95% CI 756-2216 pg/mL) and IFN-γ (852 pg/mL, 95% CI 193-1511 pg/mL) after 48 hours. This was significantly impaired in pregnant women (IFN-α; p<0.0001 and IFN-λ; p<0.001). Furthermore, in the presence of syncytin-1, PBMCs demonstrated marked reductions in IFN-α and IFN-λ, while enhanced release of IL-10 as well as IL-6 and IL-1ß. CONCLUSIONS: Our data indicates that a placental derived protein, syncytin-1 may be responsible for the heightened vulnerability of pregnant women to influenza.


Assuntos
Produtos do Gene env/farmacologia , Vírus da Influenza A Subtipo H1N1/fisiologia , Placenta/metabolismo , Proteínas da Gravidez/farmacologia , Adolescente , Adulto , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Suscetibilidade a Doenças/imunologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Humanos , Inflamação/imunologia , Inflamação/virologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Monócitos/virologia , Gravidez , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/imunologia , Adulto Jovem
10.
Biotechniques ; 43(6): 799-804, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18251257

RESUMO

We describe a procedure for the simultaneous extraction of proteins and nucleic acids from the same experimental sample allowing for direct correlations between genetic, genomic, and proteomic data. This approach, using commercially available column-based nucleic acid extraction kits, requires no hazardous chemicals and is a quick, reliable, and consistent method for concomitant protein extraction. Buffer choice is critical to completely solubilize all proteins in the sample. Proteins solubilized in radioimmunoprecipitation assay (RIPA) buffer did not represent the entire profile when compared with conventionally extracted proteins using the same buffer at the one-dimensional (1-D) sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) level, however proteins extracted from the columns and solubilized in a two-dimensional (2-D) electrophoresis lysis buffer showed a similar profile to conventionally extracted proteins when analyzed at both the 1-D and the 2-D level. We further showed that proteins extracted using these methods were compatible with Western blot analysis. This technique provides a simple and effective way to analyze protein and nucleic acids simultaneously from the same sample without affecting yield and quality.


Assuntos
Genômica/instrumentação , Genômica/métodos , Proteômica/instrumentação , Proteômica/métodos , Western Blotting/métodos , DNA/isolamento & purificação , Eletroforese em Gel Bidimensional/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Feminino , Humanos , Placenta , Gravidez , Proteínas/isolamento & purificação , RNA/isolamento & purificação , Ensaio de Radioimunoprecipitação/métodos
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