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1.
J Cosmet Dermatol ; 23(8): 2644-2656, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38590207

RESUMO

BACKGROUND: Exposure to environmental stressors like particulate matter (PM) and ultraviolet radiation (UV) induces cutaneous oxidative stress and inflammation and leads to skin barrier dysfunction and premature aging. Metals like iron or copper are abundant in PM and are known to contribute to reactive oxygen species (ROS) production. AIMS: Although it has been suggested that topical antioxidants may be able to help in preventing and/or reducing outdoor skin damage, limited clinical evidence under real-life exposure conditions have been reported. The aim of the present study was to evaluate the ability of a topical serum containing 15% ascorbic acid, 0.5% ferulic acid, and 1% tocopherol (CF Mix) to prevent oxinflammatory skin damage and premature aging induced by PM + UV in a human clinical trial. METHODS: A 4-day single-blinded, clinical study was conducted on the back of 15 females (18-40 years old). During the 4 consecutive days, the back test zones were treated daily with or without the CF Mix, followed by with/without 2 h of PM and 5 min of UV daily exposure. RESULTS: Application of the CF Mix prevented PM + UV-induced skin barrier perturbation (Involucrin and Loricrin), lipid peroxidation (4HNE), inflammatory markers (COX2, NLRP1, and AhR), and MMP9 activation. In addition, CF Mix was able to prevent Type I Collagen loss. CONCLUSION: This is the first human study confirming multipollutant cutaneous damage and suggesting the utility of a daily antioxidant topical application to prevent pollution induced skin damage.


Assuntos
Antioxidantes , Estresse Oxidativo , Material Particulado , Pele , Raios Ultravioleta , Humanos , Feminino , Raios Ultravioleta/efeitos adversos , Adulto , Antioxidantes/administração & dosagem , Método Simples-Cego , Adulto Jovem , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Material Particulado/efeitos adversos , Material Particulado/administração & dosagem , Pele/efeitos da radiação , Pele/efeitos dos fármacos , Pele/metabolismo , Adolescente , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/efeitos da radiação , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/farmacologia , Administração Cutânea , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Ácidos Cumáricos
2.
J Drugs Dermatol ; 23(4): 233-238, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38564394

RESUMO

BACKGROUND: Silymarin is an antioxidant that can protect against free radicals that cause premature signs of aging and oil oxidation that may contribute to breakouts. AIMS: The objective of these studies was to evaluate a silymarin antioxidant serum alone and in combination with a prescription acne treatment regimen in improving facial appearance in blemish-prone skin.  Methods: Two international studies were conducted. A 12-week study in Brazil enrolled 56 subjects to examine the effect of silymarin antioxidant serum on facial acne. Clinical grading on acne lesions, skin tone, clarity, and postinflammatory hyperpigmentation (PIH) were conducted. In addition, consumer self-assessment, analysis for markers of lipid peroxidation, and sebumeter analysis were completed. Another Unites States (US)/German study enrolled 40 subjects who were on topical prescription acne medications to which silymarin antioxidant serum was added. Acne lesion counts, tolerability, and facial appearance assessments were conducted in this study. RESULTS: The Brazilian study demonstrated a 45% reduction in inflammatory lesions and a 43% reduction in noninflammatory lesions after 12 weeks of silymarin antioxidant serum use. In addition, sebumeter testing showed a 16% reduction in oiliness at week 1. The US/German study showed the benefits of the serum in persons already on prescription acne therapy by reducing facial erythema by 60%, dryness by 49%, and scaling by 67%. CONCLUSION: Silymarin is shown in clinical testing to have significant benefits in reducing lipid peroxidation, oiliness, and PIH, and in improving key markers of skin aging. Additionally, the serum can be used alone or as an adjunctive treatment in acne therapy to further benefit aging, acne-prone skin. J Drugs Dermatol. 2024;23(4):     doi:10.36849/JDD.8120.


Assuntos
Acne Vulgar , Hiperpigmentação , Silimarina , Humanos , Antioxidantes/uso terapêutico , Silimarina/uso terapêutico , Administração Cutânea , Resultado do Tratamento , Acne Vulgar/diagnóstico , Acne Vulgar/tratamento farmacológico , Acne Vulgar/patologia , Hiperpigmentação/tratamento farmacológico
3.
Exp Dermatol ; 33(1): e15000, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38284201

RESUMO

Cutaneous tissues is among the main target of outdoor stressors such as ozone (O3 ), particulate matter (PM), and ultraviolet radiation (UV) all involved in inducing extrinsic skin aging. Only a few reports have studied the multipollutant interaction and its effect on skin damage. In the present work, we intended to evaluate the ability of pollutants such as O3 and PM to further aggravate cutaneous UV damage. In addition, the preventive properties of a cosmeceutical formulation mixture (AOX mix) containing 15% vitamin C (L-ascorbic acid), 1% vitamin E (α-tocopherol) and 0.5% ferulic acid was also investigated. Skin explants obtained from three different subjects were exposed to 200 mJ UV light, 0.25 ppm O3 for 2 h, and 30 min of diesel engine exhaust (DEE), alone or in combination for 4 days (time point D1 and D4). The results showed a clear additive effect of O3 and DEE in combination with UV in terms of keratin 10, Desmocollin and Claudin loss. In addition, the multipollutant exposure significantly induced the inflammatory response measured as NLRP1/ASC co-localization suggesting the activation of the inflammasome machinery. Finally, the loss of Aquaporin3 was also affected by the combined outdoor stressors. Furthermore, daily topical pre-treatment with the AOX Mix significantly prevented the cutaneous changes induced by the multipollutants. In conclusion, this study is among the first to investigate the combined effects of three of the most harmful outdoor stressors on human skin and confirms that daily topical of an antioxidant application may prevent pollution-induced skin damage.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Humanos , Ácido Ascórbico/farmacologia , Raios Ultravioleta/efeitos adversos , Vitaminas , Antioxidantes/farmacologia , Material Particulado/toxicidade
4.
Acad Radiol ; 29(1): 51-55, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33257257

RESUMO

RATIONALE AND OBJECTIVES: Leg length discrepancy studies are labor intensive. They are procedurally simple and represent inefficient use of the radiologists' time and expertise. We hypothesized that radiology technologists could be trained to measure leg length discrepancies, and that their performance would be statistically equivalent to that of board-certified, fellowship-trained pediatric radiologists. MATERIAL AND METHODS: Four radiology technologists were selected to participate in a supervised practice session. They independently measured and calculated leg length discrepancies on 10 randomly selected cases. Their performance was compared to measurements obtained by an experienced pediatric radiologist (reference standard). After 1 week, the technologists repeated their measurements on the same cases, which were resorted to simulate new cases. Intraclass correlation coefficients (ICC) determined interobserver agreement between the technologists and radiologist and intra-observer reliability among the technologists. RESULTS: Among the four technologists, similarity in measurements between session 1 and the reference standard was very high, with ICC values ranging from 0.93 to 0.98 (p < 0.001). The ICC between session 2 and the reference standard was also high, ranging from 0.93 to 0.98 (p < 0.001). Finally, among the four technologists, ICC values between session 1 and session 2 were ≥ 0.96 (p < 0.001). CONCLUSION: Radiology technologists can be rapidly trained to calculate leg length discrepancies as accurately as a board-certified pediatric radiologist. Delegation of this time-consuming task to technologists or radiology assistants will permit radiologists to spend time on more demanding studies, such as studies that require subspecialty training.


Assuntos
Perna (Membro) , Radiologia , Criança , Humanos , Radiografia , Radiologistas , Reprodutibilidade dos Testes
5.
AJR Am J Roentgenol ; 214(5): 1042-1053, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32023117

RESUMO

OBJECTIVE. The purpose of this article is to review established and emerging methods for reducing motion artifacts in pediatric abdominal MRI. CONCLUSION. Clearly understanding the strengths and limitations of motion reduction methods can enable practitioners of pediatric abdominal MRI to select and combine the appropriate techniques and potentially reduce the need for sedation and anesthesia.


Assuntos
Abdome/diagnóstico por imagem , Artefatos , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Técnicas de Imagem de Sincronização Respiratória/métodos , Criança , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Movimento (Física)
6.
J Ultrasound Med ; 39(5): 1031-1036, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31705672

RESUMO

Bowel diseases of prematurity, including necrotizing enterocolitis, are dreaded ailments of neonates. Early diagnosis is difficult, with clinical and radiographic findings often inconclusive. We present a novel use of contrast-enhanced ultrasound in detection of pediatric bowel disease. Early identification of compromised blood flow or an at-risk bowel can be quantitatively detected and monitored. This ability has implications for guidance of emerging therapies, allowing targeting of inflammation. These findings represent an advancement in detection of bowel disease in neonates.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Doenças do Prematuro/diagnóstico por imagem , Enteropatias/diagnóstico por imagem , Ultrassonografia/métodos , Diagnóstico Precoce , Evolução Fatal , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/cirurgia , Enteropatias/cirurgia , Intestinos/diagnóstico por imagem , Intestinos/cirurgia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
mSphere ; 4(1)2019 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-30814318

RESUMO

Between 2000 and 2017, a total of 236 Legionella species isolates from Arizona were submitted to the CDC for reference testing. Most of these isolates were recovered from bronchoalveolar lavage specimens. Although the incidence of legionellosis in Arizona is less than the overall U.S. incidence, Arizona submits the largest number of isolates to the CDC for testing compared to those from other states. In addition to a higher proportion of culture confirmation of legionellosis cases in Arizona than in other states, all Legionellapneumophila isolates are forwarded to the CDC for confirmatory testing. Compared to that from other states, a higher proportion of isolates from Arizona were identified as belonging to L. pneumophila serogroups 6 (28.2%) and 8 (8.9%). Genome sequencing was conducted on 113 L. pneumophila clinical isolates not known to be associated with outbreaks in order to understand the genomic diversity of strains causing legionellosis in Arizona. Whole-genome multilocus sequence typing (wgMLST) revealed 17 clusters of isolates sharing at least 99% identical allele content. Only two of these clusters contained isolates from more than one individual with exposure at the same facility. Additionally, wgMLST analysis revealed a group of 31 isolates predominantly belonging to serogroup 6 and containing isolates from three separate clusters. Single nucleotide polymorphism (SNP) and pangenome analysis were used to further resolve genome sequences belonging to a subset of isolates. This study demonstrates that culture of clinical specimens for Legionella spp. reveals a highly diverse population of strains causing legionellosis in Arizona which could be underappreciated using other diagnostic approaches.IMPORTANCE Culture of clinical specimens from patients with Legionnaires' disease is rarely performed, restricting our understanding of the diversity and ecology of Legionella Culture of Legionella from patient specimens in Arizona revealed a greater proportion of non-serogroup 1 Legionellapneumophila isolates than in other U.S. isolates examined. Disease caused by such isolates may go undetected using other diagnostic methods. Moreover, genome sequence analysis revealed that these isolates were genetically diverse, and understanding these populations may help in future environmental source attribution studies.


Assuntos
Variação Genética , Genoma Bacteriano , Legionella pneumophila/classificação , Doença dos Legionários/microbiologia , Arizona/epidemiologia , Técnicas de Tipagem Bacteriana , Centers for Disease Control and Prevention, U.S. , Genótipo , Humanos , Legionella pneumophila/isolamento & purificação , Doença dos Legionários/epidemiologia , Tipagem de Sequências Multilocus , Sorogrupo , Estados Unidos , Sequenciamento Completo do Genoma
8.
J Food Prot ; 81(8): 1283-1292, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29985066

RESUMO

On 10 August 2016, the Maricopa County Department of Public Health identified culture-confirmed Salmonella enterica serotype Javiana isolates from two persons who reported eating at a seafood restaurant; seven additional cases were reported by 15 August. We investigated to identify a source and prevent further illness. We interviewed persons with laboratory-reported Salmonella Javiana infection. Pulsed-field gel electrophoresis (PFGE) and whole genome sequencing of isolates were performed. A case was defined as diarrheal illness in a person during July to September 2016; confirmed cases had Salmonella Javiana isolate yielding outbreak-related PFGE patterns; probable cases had diarrheal illness and an epidemiologic link to a confirmed case. Case finding was performed (passive surveillance and identification of ill meal companions). A case-control study assessed risk factors for Salmonella Javiana infection among restaurant diners; control subjects were chosen among meal companions. No restaurant workers reported illness. Foods were reportedly cooked according to the Food Code. Food and environmental samples were collected and cultured; Salmonella Javiana with an indistinguishable PFGE pattern was isolated from portioned repackaged raw shrimp, halibut, and a freezer door handle. We identified 50 Salmonella Javiana cases (40 confirmed and 10 probable); illness onset range was from 22 July to 17 September 2016. Isolates from 40 patients had highly related PFGE patterns. Thirty-three (73%) of 45 patients interviewed reported eating at the restaurant. Among 21 case patients and 31 control subjects, unfried cooked shrimp was associated with illness (odds ratio, 6.7; 95% confidence interval, 1.8 to 24.9; P = 0.004). Among restaurant diners, laboratory and case-control evidence indicated shrimp as the possible outbreak source; poor thermal inactivation of Salmonella on shrimp is theorized as a possible cause. Cross-contamination might have prolonged this outbreak; however, the source was not identified and highlights limitations that can arise during these types of investigations.


Assuntos
Restaurantes , Intoxicação Alimentar por Salmonella , Salmonella enterica , Alimentos Marinhos/microbiologia , Adolescente , Adulto , Idoso , Arizona/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Surtos de Doenças , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intoxicação Alimentar por Salmonella/epidemiologia , Salmonella enterica/classificação , Salmonella enterica/isolamento & purificação , Sorogrupo , Sorotipagem , Adulto Jovem
9.
Virology ; 497: 125-135, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27467578

RESUMO

Monkeypox virus (MPXV) infection fails to activate the host anti-viral protein, PKR, despite lacking a full-length homologue of the vaccinia virus (VACV) PKR inhibitor, E3. Since PKR can be activated by dsRNA produced during a viral infection, we have analyzed the accumulation of dsRNA in MPXV-infected cells. MPXV infection led to less accumulation of dsRNA than VACV infection. Because in VACV infections accumulation of abnormally low amounts of dsRNA is associated with mutations that lead to resistance to the anti-poxvirus drug isatin beta-thiosemicarbazone (IBT), we investigated the effects of treatment of MPXV-infected cells with IBT. MPXV infection was eight-fold more resistant to IBT than wild-type vaccinia virus (wtVACV). These results demonstrate that MPXV infection leads to the accumulation of less dsRNA than wtVACV, which in turn likely leads to a decreased capacity for activation of the dsRNA-dependent host enzyme, PKR.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral , Monkeypox virus/efeitos dos fármacos , Monkeypox virus/fisiologia , RNA de Cadeia Dupla/biossíntese , Vaccinia virus/efeitos dos fármacos , Vaccinia virus/fisiologia , Linhagem Celular , DNA Viral , Células HeLa , Humanos , Fases de Leitura Aberta , Transcrição Gênica , Proteínas Virais/genética , Virulência/genética , Replicação Viral
10.
J Virol ; 86(10): 5895-904, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22419806

RESUMO

Vaccinia virus (VACV) encodes a multifunctional protein, E3L, that is necessary for interferon (IFN) resistance in cells in culture. Interferon resistance has been mapped to the well-characterized carboxy terminus of E3L, which contains a conserved double-stranded RNA binding domain. The amino terminus of E3L has a Z-form nucleic acid binding domain, which has been shown to be dispensable for replication and IFN resistance in HeLa and RK13 cells; however, a virus expressing E3L deleted of the amino terminus has reduced pathogenicity in an animal model. In this study, we demonstrate that the pathogenicity of a virus expressing E3L deleted of the amino terminus was fully rescued in type I IFN receptor knockout (IFN-α/ßR(-/-)) mice. Furthermore, this virus was IFN sensitive in primary mouse embryo fibroblasts (MEFs). This virus induced the phosphorylation of the α subunit of eukaryotic initiation factor 2 (eIF2α) in MEFs in an IFN-dependent manner. The depletion of double-stranded RNA-dependent protein kinase (PKR) from these MEFs restored the IFN resistance of this virus. Furthermore, the virus expressing E3L deleted of the amino terminus was also IFN resistant in PKR(-/-) MEFs. Thus, our data demonstrate that the amino terminus of E3L is necessary to inhibit the type I IFN response both in mice and in MEFs and that in MEFs, the amino terminus of E3L functions to inhibit the PKR pathway.


Assuntos
Interferon Tipo I/imunologia , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/imunologia , Vaccinia virus/imunologia , Vacínia/imunologia , Proteínas Virais/química , Proteínas Virais/imunologia , Motivos de Aminoácidos , Animais , Feminino , Células HeLa , Humanos , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Knockout , Proteínas de Ligação a RNA/genética , Coelhos , Receptor de Interferon alfa e beta/genética , Receptor de Interferon alfa e beta/imunologia , Vacínia/genética , Vacínia/virologia , Vaccinia virus/química , Vaccinia virus/genética , Proteínas Virais/genética
11.
PLoS One ; 7(3): e32610, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22427855

RESUMO

In the nineteenth century, smallpox ravaged through the United States and Canada. At this time, a botanical preparation, derived from the carnivorous plant Sarracenia purpurea, was proclaimed as being a successful therapy for smallpox infections. The work described characterizes the antipoxvirus activity associated with this botanical extract against vaccinia virus, monkeypox virus and variola virus, the causative agent of smallpox. Our work demonstrates the in vitro characterization of Sarracenia purpurea as the first effective inhibitor of poxvirus replication at the level of early viral transcription. With the renewed threat of poxvirus-related infections, our results indicate Sarracenia purpurea may act as another defensive measure against Orthopoxvirus infections.


Assuntos
Fitoterapia/história , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Sarraceniaceae/química , Varíola/tratamento farmacológico , Vírus da Varíola/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Animais , Canadá , Linhagem Celular , Cidofovir , Citosina/análogos & derivados , Citosina/uso terapêutico , Imunofluorescência , Células HeLa , História do Século XIX , Humanos , Técnicas In Vitro , Organofosfonatos/uso terapêutico , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Varíola/história , Estados Unidos
12.
Biotechniques ; 50(5): 303-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21548892

RESUMO

Vaccinia virus has been a powerful tool in molecular biology and vaccine development. The relative ease of inserting and expressing foreign genes combined with its broad host range has made it an attractive antigen delivery system against many heterologous diseases. Many different approaches have been developed to isolate recombinant vaccinia virus generated from homologous recombination; however, most are time-consuming, often requiring a series of passages or specific cell lines. Herein we introduce a rapid method for isolating recombinants using the antibiotic coumermycin and the interferon-associated PKR pathway to select for vaccinia virus recombinants. This method uses a negative selection marker in the form of a fusion protein, GyrB-PKR, consisting of the coumermycin dimerization domain of Escherichia coli gyrase subunit B fused to the catalytic domain of human PKR. Coumermycin-dependent dimerization of this protein results in activation of PKR and the phosphorylation of translation initiation factor, eIF2α. Phosphorylation of this factor leads to an inhibition of protein synthesis, and an inhibition of virus replication. In the presence of coumermycin, recombinants are isolated due to the loss of this coumermycin-sensitive gene by homologous recombination. We demonstrate that this method of selection is highly efficient and requires limited rounds of enrichment to isolate recombinant virus.


Assuntos
Fator de Iniciação 2 em Eucariotos/química , Vaccinia virus/isolamento & purificação , Aminocumarinas/química , Aminocumarinas/farmacologia , Animais , Linhagem Celular , Cricetinae , Dimerização , Escherichia coli/genética , Escherichia coli/metabolismo , Vetores Genéticos , Especificidade de Hospedeiro/efeitos dos fármacos , Inibidores da Síntese de Proteínas/química , Inibidores da Síntese de Proteínas/farmacologia , Coelhos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/efeitos dos fármacos , Proteínas Recombinantes/isolamento & purificação , Recombinação Genética/efeitos dos fármacos , Vaccinia virus/efeitos dos fármacos , Vaccinia virus/crescimento & desenvolvimento , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
13.
Antiviral Res ; 84(1): 1-13, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19563829

RESUMO

Vaccinia virus (VACV) has been used more extensively for human immunization than any other vaccine. For almost two centuries, VACV was employed to provide cross-protection against variola virus, the causative agent of smallpox, until the disease was eradicated in the late 1970s. Since that time, continued research on VACV has produced a number of modified vaccines with improved safety profiles. Attenuation has been achieved through several strategies, including sequential passage in an alternative host, deletion of specific genes or genetic engineering of viral genes encoding immunomodulatory proteins. Some highly attenuated third- and fourth-generation VACV vaccines are now being considered for stockpiling against a possible re-introduction of smallpox through bioterrorism. Researchers have also taken advantage of the ability of the VACV genome to accommodate additional genetic material to produce novel vaccines against a wide variety of infectious agents, including a recombinant VACV encoding the rabies virus glycoprotein that is administered orally to wild animals. This review provides an in-depth examination of these successive generations of VACV vaccines, focusing on how the understanding of poxviral replication and viral gene function permits the deliberate modification of VACV immunogenicity and virulence.


Assuntos
Vacina Antivariólica/história , Vaccinia virus/genética , Vaccinia virus/imunologia , Vacínia/prevenção & controle , Animais , Engenharia Genética , História do Século XX , História do Século XXI , Humanos , Vacina Antivariólica/genética , Vacina Antivariólica/imunologia , Vacínia/imunologia , Vacínia/virologia , Vaccinia virus/patogenicidade , Vaccinia virus/fisiologia , Virulência
14.
Steroids ; 70(5-7): 352-60, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15862817

RESUMO

Maturation, or meiotic progression, of amphibian oocytes is one of the few physiologically relevant steroid-mediated processes that occurs in the complete absence of transcription from beginning to end. As such, frog oocyte maturation has served as a useful model of nongenomic steroid signaling for many years. Earlier work in Xenopus laevis demonstrated that, although several steroids promoted oocyte maturation in vitro, androgens were the most abundant and potent steroids detected in the serum and ovaries of ovulating frogs. Thus, androgens were likely the primary physiologic regulators of Xenopus oocyte maturation, mediating their actions at least in part via classical androgen receptors expressed in oocytes. The importance of androgens for Xenopus oocyte maturation and ovulation has now been confirmed, as inhibition of androgen production in vivo by blocking CYP17 activity reduced hCG-triggered oocyte maturation and delayed ovulation in female frogs. Taking advantage of the absolute transcription-independence of this androgen-mediated response, selective androgen receptor modulators (SARMs) have been characterized that specifically promote genomic versus nongenomic androgen responses. These include androstenediol and estren, which preferentially promote nongenomic signals, as well as R1881 and 19-nortestosterone, which preferentially promote genomic signaling. Interestingly, the SARMs androstenediol and R1881 signal similarly in mouse oocytes, demonstrating the conserved nature of androgen-mediated maturation in vertebrates. These results suggest that SARMs may serve as useful tools for specifically regulating nongenomic androgen signaling both in vitro and in vivo.


Assuntos
Androgênios/metabolismo , Ovário/metabolismo , Animais , Relação Dose-Resposta a Droga , Estrenos/metabolismo , Feminino , Meiose , Metribolona/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Nandrolona/metabolismo , Oócitos/metabolismo , Ovulação , Progesterona/metabolismo , Receptores Androgênicos/metabolismo , Transdução de Sinais , Esteroide 17-alfa-Hidroxilase/metabolismo , Esteroides/metabolismo , Esteroides/farmacologia , Congêneres da Testosterona/farmacologia , Fatores de Tempo , Transcrição Gênica , Xenopus , Xenopus laevis
15.
Mol Endocrinol ; 19(8): 2035-46, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15831520

RESUMO

Classical steroid receptors mediate many transcription-independent (nongenomic) steroid responses in vitro, including activation of Src and G proteins. Estrogen-triggered activation of Src can be regulated by the modulator of nongenomic actions of the estrogen receptor (MNAR), which binds to estrogen receptors and Src to create a signaling complex. In contrast, the mechanisms regulating steroid-induced G protein activation are not known, nor are the physiologic responses mediated by MNAR. These studies demonstrate that MNAR regulates the biologically relevant process of meiosis in Xenopus laevis oocytes. MNAR was located throughout oocytes, and reduction of its expression by RNA interference markedly enhanced testosterone-triggered maturation and activation of MAPK. Additionally, Xenopus MNAR augmented androgen receptor (AR)-mediated transcription in CV1 cells through activation of Src. MNAR and AR coimmunoprecipitated as a complex involving the LXXLL-rich segment of MNAR and the ligand binding domain of AR. MNAR and Gbeta also precipitated together, with the same region of MNAR being important for this interaction. Finally, reduction of MNAR expression decreased Gbetagamma-mediated signaling in oocytes. MNAR therefore appears to participate in maintaining meiotic arrest, perhaps by directly enhancing Gbetagamma-mediated inhibition of meiosis. Androgen binding to AR might then release this inhibition, allowing maturation to occur. Thus, MNAR may augment multiple nongenomic signals, depending upon the context and cell type in which it is expressed.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Oócitos/metabolismo , Receptores Androgênicos/metabolismo , Transativadores/metabolismo , Transcrição Gênica , Sequência de Aminoácidos , Animais , Células COS , Cálcio/metabolismo , Clonagem Molecular , Proteínas Correpressoras , Relação Dose-Resposta a Droga , Subunidades beta da Proteína de Ligação ao GTP/metabolismo , Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Humanos , Imuno-Histoquímica , Imunoprecipitação , Ligantes , Sistema de Sinalização das MAP Quinases , Meiose , Modelos Biológicos , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Interferência de RNA , Receptores de Estrogênio/metabolismo , Transdução de Sinais , Testosterona/farmacologia , Fatores de Transcrição , Transfecção , Xenopus , Xenopus laevis , Quinases da Família src/metabolismo
16.
Horm Behav ; 45(3): 201-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15047015

RESUMO

Ovariectomized rats were hormonally primed with various doses of estradiol benzoate (EB; 0.5-10 microg) in combination with various doses of progesterone (2.5-500 microg) to induce sexual receptivity. Females were then subjected to 5 min restraint and the effect on lordosis behavior was monitored for the next 30 min. Such mild stress has been previously shown to transiently reduce lordosis behavior of ovariectomized females hormonally primed only with 10 microg EB. In the current study, doses of progesterone of 25 microg or more in combination with 10 microg EB reduced the effects of restraint. Also priming doses of EB from 4.0 to 10 microg in combination with 250 microg progesterone prevented the lordosis-inhibiting effects of restraint. These findings reinforce prior observations of the dose-dependency of both estrogen and progesterone in the facilitation of lordosis behavior and introduce the female's lordosis response to mild restraint as a potentially useful index of the female's response to stress.


Assuntos
Estradiol/análogos & derivados , Estradiol/administração & dosagem , Postura , Progesterona/administração & dosagem , Restrição Física , Comportamento Sexual Animal/efeitos dos fármacos , Estresse Psicológico/fisiopatologia , Animais , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Ovariectomia , Ratos , Ratos Endogâmicos F344 , Comportamento Sexual Animal/fisiologia
17.
Pharmacol Biochem Behav ; 76(1): 63-73, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-13679218

RESUMO

The effect of restraint on lordosis behavior was examined in proestrous and ovariectomized, hormone-primed rats. Restraint durations from 5 to 60 min had no effect on lordosis behavior of proestrous rats. There was also no effect of 5 min restraint on lordosis behavior of ovariectomized rats hormonally primed with 10 microg estradiol benzoate and 500 microg progesterone. However, after intraperitoneal treatment with 1.0 mg/kg ketanserin tartrate (ketanserin), 5 min of restraint significantly reduced lordosis behavior of both groups of rats. The 5-min restraint combined with 0.50 or 0.75 mg/kg ketanserin reduced lordosis to mount (L/M) ratios of ovariectomized rats, while L/M ratios of proestrous rats were inhibited only by the 1.0 mg/kg dose. Increasing the restraint duration (10 or 15 min) reduced the dose of ketanserin necessary to reduce the L/M ratios of proestrous rats. Treatment with the selective serotonin (5-HT)(2C) receptor antagonist, SB206553 (2.5 or 5.0 mg/kg), in combination with 5 min of restraint, also reduced L/M ratios of hormonally primed, ovariectomized rats. The neural sites responsible for ketanserin's additivity with restraint are unknown, but infusion of the drug into the ventromedial nucleus of the hypothalamus (VMN) did not mimic the systemic treatment. However, 5 min of restraint did enhance the effects of VMN infusion with the 5-HT(1A) receptor agonist, 8-OH-DPAT. In contrast, 8-OH-DPAT's systemic potency was not enhanced by restraint. These findings support the hypothesis that a mild stressor increases the lordosis-inhibiting effects of 5-HT(1A) receptor agonists and that 5-HT(2) receptors may protect against such disruption of lordosis behavior.


Assuntos
Postura/fisiologia , Agonistas do Receptor 5-HT1 de Serotonina , Antagonistas do Receptor 5-HT2 de Serotonina , Comportamento Sexual Animal/fisiologia , Animais , Relação Dose-Resposta a Droga , Feminino , Masculino , Ovariectomia , Proestro/efeitos dos fármacos , Proestro/fisiologia , Ratos , Ratos Endogâmicos F344 , Receptor 5-HT1A de Serotonina/fisiologia , Receptores 5-HT2 de Serotonina/fisiologia , Restrição Física , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos
18.
Brain Res ; 974(1-2): 202-11, 2003 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-12742638

RESUMO

Ovariectomized, hormone-primed rats were used to test the hypothesis that progesterone treatment attenuated the effects of the 5-HT(1A) receptor agonist, (+/-)-8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), on female rat lordosis behavior. Based upon prior evidence that prepriming with estradiol benzoate (EB) reduced the ability of 8-OH-DPAT to inhibit lordosis behavior, rats were preprimed with 10 microg EB 7 days before a second priming with 10 microg EB followed 48 h later with 500 microg progesterone or vehicle. Independent of the presence of progesterone, prepriming with EB attenuated the lordosis-inhibiting effects of systemic treatment with 8-OH-DPAT. However, progesterone also reduced the effects of 8-OH-DPAT and this effect was also seen in females primed only once with EB. In contrast, progesterone was relatively ineffective in attenuating the effects of bilateral infusion with 8-OH-DPAT into the ventromedial nucleus of the hypothalamus (VMN). The failure of progesterone to substantially reduce the effects of VMN infusion with 8-OH-DPAT contrasts with prior studies in which estrogen's protective action against the drug did include the VMN. Thus, while both estrogen and progesterone reduce the lordosis-inhibiting effect of 8-OH-DPAT, the mechanisms responsible for the effects of the two gonadal hormones may be different. Priming with progesterone also prevented the effects of 5 min of restraint. When rats were hormonally primed with EB and oil, rats showed a transient, but significant, decline in lordosis behavior 5 and 10 min after restraint. Rats primed with EB and progesterone were unaffected by the restraint. These results are discussed in terms of their implications for the role of progesterone in altering the 5-HT(1A) receptor modulation of lordosis behavior.


Assuntos
8-Hidroxi-2-(di-n-propilamino)tetralina/antagonistas & inibidores , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Postura/fisiologia , Progesterona/farmacologia , Receptores de Serotonina/efeitos dos fármacos , Agonistas do Receptor de Serotonina/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Estresse Psicológico/psicologia , Animais , Relação Dose-Resposta a Droga , Estrogênios/farmacologia , Feminino , Ovariectomia , Ratos , Ratos Endogâmicos F344 , Receptores 5-HT1 de Serotonina , Restrição Física
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