Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 36
Filtrar
1.
Proc Natl Acad Sci U S A ; 111(14): E1383-92, 2014 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-24706903

RESUMO

Deafness caused by the terminal loss of inner ear hair cells is one of the most common sensory diseases. However, nonmammalian animals (e.g., birds, amphibians, and fish) regenerate damaged hair cells. To understand better the reasons underpinning such disparities in regeneration among vertebrates, we set out to define at high resolution the changes in gene expression associated with the regeneration of hair cells in the zebrafish lateral line. We performed RNA-Seq analyses on regenerating support cells purified by FACS. The resulting expression data were subjected to pathway enrichment analyses, and the differentially expressed genes were validated in vivo via whole-mount in situ hybridizations. We discovered that cell cycle regulators are expressed hours before the activation of Wnt/ß-catenin signaling following hair cell death. We propose that Wnt/ß-catenin signaling is not involved in regulating the onset of proliferation but governs proliferation at later stages of regeneration. In addition, and in marked contrast to mammals, our data clearly indicate that the Notch pathway is significantly down-regulated shortly after injury, thus uncovering a key difference between the zebrafish and mammalian responses to hair cell injury. Taken together, our findings lay the foundation for identifying differences in signaling pathway regulation that could be exploited as potential therapeutic targets to promote either sensory epithelium or hair cell regeneration in mammals.


Assuntos
Perfilação da Expressão Gênica , Células Ciliadas Auditivas/citologia , Regeneração , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Citometria de Fluxo , Genes cdc , Células Ciliadas Auditivas/fisiologia , Neomicina/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Receptores Notch/metabolismo , Transdução de Sinais , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
3.
Cells ; 13(16)2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39195268

RESUMO

Tracking cell death in vivo can enable a better understanding of the biological mechanisms underlying tissue homeostasis and disease. Unfortunately, existing cell death labeling methods lack compatibility with in vivo applications or suffer from low sensitivity, poor tissue penetration, and limited temporal resolution. Here, we fluorescently labeled dead cells in vivo with Trypan Blue (TBlue) to detect single scattered dead cells or to generate whole-mount three-dimensional maps of large areas of necrotic tissue during organ regeneration. TBlue effectively marked different types of cell death, including necrosis induced by CCl4 intoxication in the liver, necrosis caused by ischemia-reperfusion in the skin, and apoptosis triggered by BAX overexpression in hepatocytes. Moreover, due to its short circulating lifespan in blood, TBlue labeling allowed in vivo "pulse and chase" tracking of two temporally spaced populations of dying hepatocytes in regenerating mouse livers. Additionally, upon treatment with cisplatin, TBlue labeled dead cancer cells in livers with cholangiocarcinoma and dead thymocytes due to chemotherapy-induced toxicity, showcasing its utility in assessing anticancer therapies in preclinical models. Thus, TBlue is a sensitive and selective cell death marker for in vivo applications, facilitating the understanding of the fundamental role of cell death in normal biological processes and its implications in disease.


Assuntos
Morte Celular , Azul Tripano , Animais , Camundongos , Morte Celular/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Hepatócitos/metabolismo , Humanos , Neoplasias/patologia , Camundongos Endogâmicos C57BL , Regeneração Hepática/efeitos dos fármacos , Fígado/patologia , Fígado/efeitos dos fármacos , Rastreamento de Células/métodos , Apoptose/efeitos dos fármacos , Imageamento Tridimensional , Regeneração/efeitos dos fármacos , Necrose , Masculino
4.
Zebrafish ; 21(2): 119-127, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38621203

RESUMO

Research-based education at the undergraduate level is ideal for fostering the training of future scientists. In an undergraduate Developmental Biology course, this learning strategy requires the availability of model species and enough research reagents, not only for technique training but also for the development of student original projects. This might be challenging in most countries, where resources are limited. Hence, there is a need to develop low-cost solutions for use in the classroom. In this study, we describe the optimization and use of two low-cost protocols in zebrafish embryos for hands-on practical sessions and project-based learning in a Developmental Biology undergraduate course in Ecuador. These protocols were designed for the practical and experimental learning of vertebrate meroblastic cleavage, gastrulation, and neural crest differentiation. The proposed protocols have been previously described in the literature and use silver nitrate and alcian blue, two relatively inexpensive reagents, to label cell membranes and cartilage. The silver nitrate protocol allows the study of cell contact formation during cleavage and the identification of cellular changes during gastrulation, including yolk internalization and epiboly. The alcian blue staining allows the analysis of cranial mesenchymal differentiation into cartilage. These protocols are ideal for practical sessions due to their ease of application, quick results, adaptability to the class schedule, and robustness in the hands of beginning researchers. Finally, these protocols are adaptable for research-based class projects.


Assuntos
Nitrato de Prata , Peixe-Zebra , Humanos , Animais , Equador , Azul Alciano , Biologia do Desenvolvimento
5.
Mult Scler Relat Disord ; 79: 105012, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37797392

RESUMO

INTRODUCTION: Multiple Sclerosis (MS) is a chronic disease affecting around 2.8 million people worldwide. Two-thirds are women, and the mean age at diagnosis is about 30 years old. Social trends are moving towards older age at first pregnancy, both in women with and without MS. OBJECTIVES: To determine the frequency of diminished ovarian reserve (DOR) through anti-Mullerian Hormone (AMH) measurement in women with MS at fertile age and Healthy Females (HF) in Chile. METHODS: Case-control, multicentric, cross-sectional study including relapsing-remitting people with MS (pwMS) between 18 and 40 years and sex and age-matched HF. We obtained a blood sample to determine AMH levels. We defined DOR as AMH <1.5 ng/mL and very-low AMH levels as <0.5 ng/mL. Also, we performed questions regarding reproductive decision-making. RESULTS: We included 79 sex and age-matched HF and 92 pwMS, median age 32(19-40) years, median disease duration 6 (1-17)years, median EDSS 1.0 (0-6), 95% were receiving disease-modifying therapy (DMT), 70% high-efficacy DMT and 37% with a treatment that contraindicates pregnancy. DOR was observed in 24% (n = 22) of the pwMS, compared to 14% (n = 11) of the HF (p = 0.09), while very-low AMH levels were observed in 7.6% (n = 7) of pwMS and none of the HF (p = 0.0166). We observed an inverse correlation between age and AMH levels. Age was the only significant risk factor for low AMH levels in pwMS (OR 1.14 95%CI(1.00-1-31), p = 0.04), including smoking, body mass index (BMI), hormonal contraception, autoimmune comorbidity, high/low-moderate efficacy DMT, and active disease as covariables. We did not find statistically significant differences in age at diagnosis, BMI, disease duration, EDSS, autoimmune comorbidity, use of hormonal contraception, or percentage of active disease between MS women with normal vs DOR. Over 70% of pwMS desired to become pregnant in the future, while 60% considered that the diagnosis of MS was a limitation for pregnancy planning. CONCLUSIONS: No differences in DOR, measured by levels of AMH, were observed between pwMS MS and HF in Chile. As expected, AMH levels were correlated only with ageing. This information may be evaluated early during the disease course to help patients and neurologists with fertility counselling and family planning considerations regarding DMT use.


Assuntos
Esclerose Múltipla , Reserva Ovariana , Gravidez , Humanos , Feminino , Adulto , Masculino , Esclerose Múltipla/epidemiologia , Estudos Transversais , Chile/epidemiologia , Envelhecimento
6.
J Morphol ; 284(5): e21582, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36964924

RESUMO

Andean Toads of the genus Osornophryne are suspected to have direct development on the basis of clutch and egg features. In this work, we describe the morphology of Osornophryne occidentalis embryos from a nest collected in the field. Several traits are similar to those reported in brachycephaloid Eleutherodactylus coqui and other direct-developing lineages. These include the pattern of formation of the body wall and the absence of oral and buccopharyngeal structures. Other features indicate the retention of ancestral larval characters. The development of forelimbs occurs in part within the operculum as in species with biphasic ontogeny; this has been reported in other direct-developing species, and is similar to what is described in African viviparous bufonids. This salient feature, along with the long, low-finned tail and the long and folded intestine early differentiated, gives these embryos a rather tadpole-like appearance. Our data confirm that development in O. occidentalis occurs within terrestrial eggs until advanced stages, and this would satisfy current definitions of direct development. At the same time, morphological differences regarding other species with comparable breeding reinforce interpretations about the wide anatomical and ontogenetic variations associated with endotrophic nutrition.


Assuntos
Bufonidae , Animais , Larva
7.
Animals (Basel) ; 11(11)2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34827756

RESUMO

It has been suggested that gymnophthalmids, like most semi-fossorial lacertoids, rely more in chemical cues to communicate, in comparison to other groups, like Iguanids, on which communication is mostly based on visual signaling. We present the first description of visual signaling in the Andean lizard Pholidobolusmontium (Gymnophthalmidae) and a complete ethogram based on ex situ observations (34 different types of behaviors including positions and simple movements). Through the design of conspecific stimulus experiments, we were able to recognize leg-waving as a visual signal, as it is only displayed in presence of conspecifics or in presence of a mirror and was one of first and most frequent displays in this context. We also detected other visual displays like neck-arching and tail-undulation which may also be relevant as visual signals. Based on our results, we propose that visual signaling is also possible in semi-fossorial lizards; however, further studies regarding chemical signal recognition and color detection are required to confirm our hypothesis.

8.
Int J Dev Biol ; 65(4-5-6): 333-344, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32930380

RESUMO

The adaptive role of amphibian oocyte melanic pigmentation and its molecular control are still elusive. Here we present evidence of a polymorphism in egg pigmentation in the emerald glass frog Espadarana prosoblepon. In Ecuadorian natural populations of this species, females can lay dark brown or pale eggs that develop into normal pigmented tadpoles and adults. This trait is a sex-limited phenotype which is inherited like a recessive allele that we called pale eggs like (pel). The pel phenotype is exclusive of oocyte cortical melanic pigmentation, which is reduced in comparison to wild type (wt) dark pigmented oocytes. Consequently, pel early embryos are paler in appearance, with reduced melanic pigmentation distributed to early blastomeres and embryonic ectoderm. However, these embryos form normal melanocyte derived pigmentation. Finally, we discuss the origin of this polymorphism and propose the use of E. prosoblepon as a model to study the adaptive role of egg pigmentation.


Assuntos
Anuros , Oócitos , Pigmentação , Animais , Anuros/genética , Blastômeros , Feminino , Fenótipo , Pigmentação/genética
9.
Dev Cell ; 56(9): 1296-1312.e7, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33878346

RESUMO

Mammalian inner ear and fish lateral line sensory hair cells (HCs) detect fluid motion to transduce environmental signals. Actively maintained ionic homeostasis of the mammalian inner ear endolymph is essential for HC function. In contrast, fish lateral line HCs are exposed to the fluctuating ionic composition of the aqueous environment. Using lineage labeling, in vivo time-lapse imaging and scRNA-seq, we discovered highly motile skin-derived cells that invade mature mechanosensory organs of the zebrafish lateral line and differentiate into Neuromast-associated (Nm) ionocytes. This invasion is adaptive as it is triggered by environmental fluctuations. Our discovery of Nm ionocytes challenges the notion of an entirely placodally derived lateral line and identifies Nm ionocytes as likely regulators of HC function possibly by modulating the ionic microenvironment. Nm ionocytes provide an experimentally accessible in vivo system to study cell invasion and migration, as well as the physiological adaptation of vertebrate organs to changing environmental conditions.


Assuntos
Adaptação Fisiológica , Movimento Celular , Meio Ambiente , Homeostase , Sistema da Linha Lateral/citologia , Peixe-Zebra/fisiologia , Animais , Biomarcadores/metabolismo , Contagem de Células , Fatores de Transcrição Forkhead/metabolismo , Brânquias/citologia , Células Ciliadas Auditivas/citologia , Concentração de Íons de Hidrogênio , Imageamento Tridimensional , Receptores Notch/metabolismo , Salinidade , Transdução de Sinais , Pele/citologia , Proteínas de Peixe-Zebra/metabolismo
10.
Elife ; 82019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30681411

RESUMO

Loss of sensory hair cells leads to deafness and balance deficiencies. In contrast to mammalian hair cells, zebrafish ear and lateral line hair cells regenerate from poorly characterized support cells. Equally ill-defined is the gene regulatory network underlying the progression of support cells to differentiated hair cells. scRNA-Seq of lateral line organs uncovered five different support cell types, including quiescent and activated stem cells. Ordering of support cells along a developmental trajectory identified self-renewing cells and genes required for hair cell differentiation. scRNA-Seq analyses of fgf3 mutants, in which hair cell regeneration is increased, demonstrates that Fgf and Notch signaling inhibit proliferation of support cells in parallel by inhibiting Wnt signaling. Our scRNA-Seq analyses set the foundation for mechanistic studies of sensory organ regeneration and is crucial for identifying factors to trigger hair cell production in mammals. The data is searchable and publicly accessible via a web-based interface.


Assuntos
Proliferação de Células , Fatores de Crescimento de Fibroblastos/metabolismo , Células Ciliadas Auditivas/citologia , RNA Citoplasmático Pequeno/genética , Receptores Notch/metabolismo , Transdução de Sinais , Células-Tronco/metabolismo , Animais , Peixe-Zebra
11.
Biol Bull ; 234(3): 165-179, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29949441

RESUMO

There are a limited number of model species for decapod experimental embryology. To improve our understanding of developmental pattern evolution in the Decapoda, here we describe the early embryonic development of the caridean shrimp Lysmata boggessi, from immediately after fertilization to the hatching of the zoea larva, using fluorescence microscopy and whole-mount nuclear staining with 4',6-diamidino-2-phenylindole. Lysmata boggessi follows the standard caridean pattern of early development, with early holoblastic cleavage that will later become superficial, to form a blastoderm. We found no evidence of stereotypical cleavage and the formation of blastomere interlocking bands, which suggests there is diversity in developmental patterns within the Caridea. Gastrulation starts 37 hours after fertilization, and the embryonized nauplius is formed 2 days later. Enlarged headlobes, early retinal differentiation, and delayed pereopod development are characteristics of the post-naupliar stages in this species. To facilitate comparative studies with other crustacean species, we propose a staging method based on our findings. Lysmata boggessi is a protandric simultaneous hermaphrodite that is relatively easy to breed in captivity and amenable to laboratory experimentation in studies of embryonic development.


Assuntos
Decápodes/embriologia , Desenvolvimento Embrionário/fisiologia , Animais
12.
J Clin Endocrinol Metab ; 90(2): 1181-8, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15562024

RESUMO

Progesterone in hormonal preparations increases the incidence of breast cancer. Tissue factor (TF), the initiator of the extrinsic coagulation pathway, is associated with metastasis in a wide variety of cancers. We demonstrate herein that TF mRNA and protein are up-regulated by progesterone in the breast cancer cell line ZR-75. Epidermal growth factor, also associated with increased breast cancer risk, did not regulate TF. The increase in TF is both rapid and transient; increasing after 6 h, reaching a maximum at 24 h, before decreasing to basal levels at 72 h. Sucrose gradient experiments demonstrated that TF is located in the heavy fraction of the plasma membrane, although caveolin-1 is not expressed in ZR-75. To understand the physiological implications of an increase in TF, we performed coagulation and invasion assays. An increase in TF corresponded to an increase in procoagulant activity. Furthermore, progesterone increased the invasion of ZR-75 cells through a matrigel, an effect that was blocked by an antibody against TF. Because TF expression is associated with an enhanced risk of metastasis, we postulate that the progesterone-dependent up-regulation of TF provides a survival advantage to burgeoning breast cancer cells and may contribute to the increased risk of cancer associated with combined hormone replacement therapy.


Assuntos
Neoplasias da Mama/genética , Progesterona/farmacologia , Tromboplastina/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Neoplasias do Endométrio , Fator de Crescimento Epidérmico/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Invasividade Neoplásica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sacarose , Tromboplastina/isolamento & purificação
13.
Thromb Haemost ; 94(2): 444-53, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16113838

RESUMO

Tissue Factor (TF), the initiator of the extrinsic coagulation cascade, is overexpressed in a variety of cancers. TF is also expressed in normal human endometrium but little is known about its expression or regulation in endometrial cancer. We demonstrate herein that TF is expressed in the endometrial adenocarcinoma cell line Ishikawa. Furthermore, epidermal growth factor (EGF) induces a rapid and sustained increase in TF expression. Estradiol and progesterone had no effect on basal or EGF-induced TF expression in Ishikawa cells. In contrast to the pronounced and sustained upregulation at the protein level, EGF treatment elicited only a modest and transient increase in TF mRNA levels. This activity corresponded to the response observed from an exogenous TF promoter construct. However, the induction of TF was abrogated by cycloheximide as well as actinomycin-D, inhibitors or protein- and mRNA-synthesis, respectively, demonstrating that EGF mediates its effect through activation of the TF gene. Fractionation experiments showed that EGF increases TF presence in caveolin-I containing membrane fractions. Coagulation and invasion assays were used to explore the physiological implications of TF regulation. The results demonstrate that EGF-mediated induction of TF increases the procoagulant activity and invasive potential of Ishikawa cells. Furthermore, immunocytochemistry confirmed that TF is regulated by EGF in primary cultures of normal endometrial epithelial cells and malignant tumor cells. In conclusion, EGF-mediated upregulation of TF results in accumulation of this glycoprotein in caveolae-like membrane fractions and increased coagulative and invasive potential. Our results suggest that TF may play an integral role in endometrial carcinogenesis.


Assuntos
Neoplasias do Endométrio/metabolismo , Endométrio/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Regulação Neoplásica da Expressão Gênica , Tromboplastina/metabolismo , Adenocarcinoma/metabolismo , Anticoagulantes/farmacologia , Western Blotting , Linhagem Celular Tumoral , Células Cultivadas , Coagulantes/metabolismo , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Detergentes/farmacologia , Endométrio/citologia , Endométrio/patologia , Estradiol/metabolismo , Feminino , Glicoproteínas/metabolismo , Humanos , Imuno-Histoquímica , Inibidores da Síntese de Ácido Nucleico/farmacologia , Octoxinol/farmacologia , Progesterona/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Sacarose/farmacologia , Fatores de Tempo , Transfecção , Ultracentrifugação , Regulação para Cima
14.
Rev. chil. obstet. ginecol. (En línea) ; 85(5): 433-441, 2020. graf
Artigo em Espanhol | LILACS | ID: biblio-1508004

RESUMO

La sobrevida de pacientes con cáncer ha mejorado con el tiempo, especialmente en pacientes en edad fértil. La criopreservación de los ovocitos a través de la estimulación ovárica controlada (EOC) es la técnica más frecuente de preservación de la fertilidad. El objetivo del presente estudio es realizar un análisis descriptivo de los ciclos de pacientes que, previo al tratamiento de cáncer, realizaron un tratamiento de preservación de fertilidad. Se analizaron datos demográficos como edad, diagnóstico de ingreso y resultados clínicos, tales como tipo de protocolo de estimulación utilizado, número de ovocitos obtenidos, duración de la estimulación y momento de inicio en el ciclo. Resultados: La edad promedio fue 28.9 años. La duración media de la estimulación fue de 12 días, con un promedio de ovocitos obtenidos en total de 12. Se utilizaron 2 protocolos de estimulación ovárica, obteniendo mejores resultados con el esquema de antagonistas de GnRH asociado a letrozole y doble gatillante. Respecto al momento del ciclo en que se inició la estimulación ovárica, no hubo diferencias. Conclusiones: Es posible realizar preservación de la fertilidad previo a un tratamiento oncológico con buenos resultados en pacientes jóvenes, por lo que sugerimos realizarlo en todos los pacientes con diagnóstico oncológico antes el tratamiento del cáncer. Es recomendable comenzar la estimulación ovárica en cualquier fase del ciclo ya que se obtienen los mismos resultados y permite un pronto inicio de la terapia oncológica.


Survival of patients with cancer has been improving over time, especially in young patient with fertility intention. Cryopreservation of oocytes through controlled ovarian stimulation (EOC) is the most frequent technique of fertility preservation. We analyzed the data obtained from oncological patients who attended IVI Chile between January 2008 and May 2017 in search of fertility preservation. Demographic data were obtained: age, diagnosis of admission, type of stimulation protocol used, number of oocytes obtained, duration of stimulation and pregnancy rate. Results: The average age: 28,9 years; average duration of stimulation:12 days. Number of oocytes obtained in total: 12. Two ovarian stimulation protocols were used. The one with the best results was the protocol with GnRH antagonists associated with letrozole and double triggering. Regarding the moment of the cycle where to start ovarian stimulation, there were no differences. Conclusions: It is possible to carry out a fertility preservation treatment prior to an oncological treatment with good results in young patients, so we suggest the preservation of fertility in all patients with an oncological diagnosis before oncological treatment. It is recommended to start ovarian stimulation at any phase of the cycle since the same results are obtained.


Assuntos
Humanos , Feminino , Adolescente , Adulto , Adulto Jovem , Oócitos/fisiologia , Indução da Ovulação/métodos , Vitrificação , Preservação da Fertilidade/métodos , Neoplasias , Criopreservação/métodos , Medicina Reprodutiva
15.
Dev Cell ; 34(3): 267-82, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26190147

RESUMO

In vertebrates, mechano-electrical transduction of sound is accomplished by sensory hair cells. Whereas mammalian hair cells are not replaced when lost, in fish they constantly renew and regenerate after injury. In vivo tracking and cell fate analyses of all dividing cells during lateral line hair cell regeneration revealed that support and hair cell progenitors localize to distinct tissue compartments. Importantly, we find that the balance between self-renewal and differentiation in these compartments is controlled by spatially restricted Notch signaling and its inhibition of Wnt-induced proliferation. The ability to simultaneously study and manipulate individual cell behaviors and multiple pathways in vivo transforms the lateral line into a powerful paradigm to mechanistically dissect sensory organ regeneration. The striking similarities to other vertebrate stem cell compartments uniquely place zebrafish to help elucidate why mammals possess such low capacity to regenerate hair cells.


Assuntos
Células Ciliadas Auditivas/fisiologia , Receptores Notch/metabolismo , Regeneração/fisiologia , Proteínas Wnt/metabolismo , Peixe-Zebra/embriologia , Animais , Diferenciação Celular/fisiologia , Linhagem da Célula , Proliferação de Células , Células Cultivadas , Mecanorreceptores/metabolismo , Receptores Notch/antagonistas & inibidores , Células-Tronco/citologia , Proteínas Wnt/antagonistas & inibidores , Via de Sinalização Wnt/fisiologia , Proteínas de Peixe-Zebra/metabolismo
16.
Endocrinology ; 144(10): 4527-35, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12960090

RESUMO

Breast cancer incidence increases in women receiving combined estrogen and progesterone therapy. Breast tumors show increased expression of the glucose transporter GLUT1. We determined the effect of these hormones on GLUT1-4 expression and deoxyglucose transport in ZR-75-1 breast cancer cells. Immunoblotting, immunocytochemistry, flow cytometry, and RT-PCR showed that GLUT1 expression is up-regulated by progesterone and, to a greater degree, combined therapy. GLUT2 expression is unaffected by hormonal treatment. GLUT3 protein and RNA is up-regulated by progesterone and combined therapy, and GLUT4 protein expression is up-regulated by all hormonal treatments. Deoxyglucose transport studies revealed the presence of three transport components with characteristics corresponding to GLUT1/4, GLUT2, and GLUT3. 17beta-Estradiol produced a slight increase in transport at the Michaelis constant (Km) corresponding to GLUT3. Progesterone produced a small increase in transport at the Km corresponding to GLUT1/4, and combined 17beta-estradiol and progesterone produced a small increase in transport at the Km corresponding to GLUT3 and a large increase in transport at the Km corresponding to GLUT1/4. This indicates that 17beta-estradiol and progesterone differentially regulate GLUT1-4 expression and that these changes correlate to changes in glucose uptake. We postulate that combined hormone replacement therapy provides a survival advantage to developing ZR-75 breast cancer cells.


Assuntos
Neoplasias da Mama/metabolismo , Estradiol/farmacologia , Proteínas de Transporte de Monossacarídeos/metabolismo , Progesterona/farmacologia , Desoxiglucose/farmacocinética , Feminino , Humanos , Proteínas de Transporte de Monossacarídeos/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas , Regulação para Cima
17.
J Endocrinol ; 182(3): 467-78, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15350188

RESUMO

Estrogen replacement therapy and other unopposed estrogen treatments increase the incidence of endometrial abnormalities, including cancer. However, this effect is counteracted by the co-administration of progesterone. In the endometrium, glucose transporter (GLUT) expression and glucose transport are known to fluctuate throughout the menstrual cycle. Here, we determined the effect of estrogen and progesterone on the expression of GLUT1-4 and on the transport of deoxyglucose in Ishikawa endometrial cancer cells. Cells were incubated with estrogen, progesterone or combined estrogen and progesterone for 24 h and the effect on the expression of GLUT1-4 and on deoxyglucose transport was determined. We show that GLUT1 expression is upregulated by estrogen and progesterone individually, but that combined estrogen and progesterone treatment reverses this increase. Hormonal treatments do not affect GLUT2, GLUT3 or GLUT4 expression. Transport studies demonstrate that estrogen increases deoxyglucose transport at Michaelis-Menten constants (Kms) corresponding to GLUT1/4, an effect which disappears when progesterone is added concomitantly. These data demonstrate that different hormonal treatments differentially regulate GLUT expression and glucose transport in this endometrial cancer cell line. This regulation mirrors the role played by estrogen and progesterone on the incidence of cancer in this tissue and suggests that GLUT1 may be utilized by endometrial cancer cells to fuel their demand for increased energy requirement.


Assuntos
Neoplasias do Endométrio/metabolismo , Estrogênios/farmacologia , Regulação da Expressão Gênica , Proteínas de Transporte de Monossacarídeos/metabolismo , Progesterona/farmacologia , Transporte Biológico , Western Blotting/métodos , Linhagem Celular Tumoral , Desoxiglucose/análise , Desoxiglucose/metabolismo , Feminino , Transportador de Glucose Tipo 1 , Transportador de Glucose Tipo 2 , Transportador de Glucose Tipo 3 , Transportador de Glucose Tipo 4 , Humanos , Imuno-Histoquímica/métodos , Proteínas de Transporte de Monossacarídeos/análise , Proteínas Musculares/análise , Proteínas Musculares/metabolismo , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Peptides ; 23(9): 1663-71, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12217427

RESUMO

Neuropeptide Y (NPY) and noradrenaline (NA) are co-transmitters at many sympathetic synapses, but it is not yet clear if their release is independently regulated. To address this question, we quantified the electrically evoked release of these co-transmitters from perivascular nerve terminals to the mesenteric circulation in control and drug-treated rats. 6-Hydroxydopamine reduced the tissue content and the electrically evoked release of ir-NPY and NA as well as the rise in perfusion pressure. A 0.001 mg/kg reserpine reduced the content of ir-NPY and NA, but did not modify their release nor altered the rise in perfusion pressure elicited by the electrical stimuli. However, 0.1mg/kg reserpine reduced both the content and release of NA but decreased only the content but not the release of ir-NPY; the rise in perfusion pressure was halved. Clonidine did not affect the release of ir-NPY while it lowered the outflow of NA, not altering the rise in perfusion pressure elicited by the electrical stimuli. Yohimbine, did not modify the release of ir-NPY but increased the NA outflow, it antagonized the clonidine effect. Therefore, presynaptic alpha2-adrenoceptors modulate the release of NA but not NPY, implying separate regulatory mechanisms.


Assuntos
Neurônios/metabolismo , Neuropeptídeo Y/metabolismo , Norepinefrina/metabolismo , Receptores Adrenérgicos alfa 2/fisiologia , Acetilcolinesterase/metabolismo , Animais , Clonidina/farmacologia , Dopamina beta-Hidroxilase/metabolismo , Relação Dose-Resposta a Droga , Imuno-Histoquímica , Microscopia de Fluorescência , Oxidopamina/metabolismo , Ratos , Ratos Sprague-Dawley , Reperfusão , Reserpina/farmacologia , Fatores de Tempo , Distribuição Tecidual , Ioimbina/farmacologia
19.
Rev. bioméd. (México) ; 28(1): 11-27, ene.-abr. 2017. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1003365

RESUMO

Resumen Introducción El consumo de tabaco es la primera causa prevenible de muerte prematura y enfermedad en todo el mundo; asimismo el uso y abuso de drogas constituye un grave problema de salud pública y de altos costos de atención a la salud. Se aborda el consumo de tabaco y drogas, desde el punto de vista epidemiológico y en materia de salud pública, así como los factores sociodemográficos que influyen en la adicción a ellos. Objetivo Describir las características socio-demográficas y de consumo de tabaco y droga en estudiantes universitarios de Yucatán y Coahuila. Material y métodos Encuesta transversal que incluyó 412 universitarios de Yucatán y 344 de Coahuila. Se utilizó estadística descriptiva para las variables numéricas y frecuencias para las cualitativas, estadística inferencial para las coincidencias y diferencias. Resultados La media de edad fue mayor para los estudiantes de Yucatán así como predominio de los hombres, la media de consumidores de tabaco dentro de las personas de su red fue mayor para Coahuila siendo las diferencias estadísticamente significativas p<0.05, no así para las personas de la red respecto al consumo de drogas. Conclusiones El consumo de tabaco en ambos estados fue mayor al esperado para su región, las fumadoras activas estuvieron por encima del promedio nacional, los dos estados se ubicaron arriba del promedio nacional respecto a consumo de drogas y Coahuila por encima del promedio mundial. Se propone un trabajo conjunto para evaluar los spots publicitarios transmitidos en los medios de comunicación y evitar su incorporación al mercado como bienes de consumo.


Abstract Introduction Tobacco consumption is the leading cause of premature preventable death and disease worldwide, as well the drug use and abuse is a serious public health problem and health care high costs. The tobacco and drugs consumption is addressed from the epidemiologic and public health point of view, also the socio-demographic factors influencing addiction to them Objetive Describe the sociodemographic and tobacco and drugs consumption characteristics among college students from Yucatan and Coahuila Materials and methods Cross sectional survey that included 412 college students from Yucatan and 344 from Coahuila. Descriptive statistics were used for the numeric variables, frequencies for the qualitative, inferential statistics for the similarities and differences. Results The mean of the age was higher for Yucatan students and men predominated, the mean of the tobacco consumers within people from their social network was higher for Coahuila being the differences statistically significant p<0.05, not so for the people from their network regarding to drugs consumption Conclusions The tobacco consumption in both states was higher than expected for the region, the active female smokers were above the national mean, the two states were above the national mean regarding to drugs use and Coahuila above the world mean. Joint work is proposed to evaluate the advertising spots broadcast in the media and avoid its incorporation to the market as consumer goods.

20.
Rev. bioméd. (México) ; 27(2): 49-60, may.-ago. 2016. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1041923

RESUMO

Resumen Introducción Los problemas de la imagen corporal asociados con los riesgos de trastornos alimenticios entre los adolescentes, en particular, la anorexia nerviosa y la bulimia, son considerados temas de salud emergentes a nivel mundial. Las consecuencias que conllevan son físicas, psicológicas y sociales. Objetivo Determinar la concordancia entre el índice de masa corporal y la percepción de la imagen corporal en un grupo de adolescentes. Materiales y Métodos Estudio cuantitativo, observacional, transversal realizado en 84 alumnos, 54.1% hombres y 45.9%, mujeres, con edades entre 10 y 17 años, que cursaban educación básica y secundaria en una localidad suburbana de alta marginación, en Yucatán. Se auto-administró a los estudiantes, el pictograma de Stunkard, para registrar la percepción de la imagen corporal. Para calcular el índice de masa corporal (IMC) se registraron medidas antropométricas de peso y talla, usando una báscula digital marca Tanita, modelo TBC 310 y un estadímetro marca SECA de 2 metros de longitud. Los puntos de corte fueron los establecidos por la Organización Mundial de la Salud. Resultados Los hallazgos, respecto a la percepción de la imagen corporal, mostraron una concordancia insignificante (k= 0.067, p< 0.5); en mujeres es baja, con un valor de k= .223; se perciben normales aun cuando presentan bajo peso, mientras que, las que presentan obesidad, subestiman su estado. En cuanto a los hombres, en los casos de obesidad, la imagen y el IMC son coincidentes, aunque, al mismo tiempo, subestiman la percepción corporal en bajo peso.


Abstract Introduction Body image problems associated with the risk of eating disorders such as anorexia nervosa and bulimia, are considered emerging health issues among adolescents around the world. These problems have both physical, psychological and social consequences. Objective To determine the correlation between body mass index and the body image perception in a group of teenagers. Material and Methods A quantitative, observational, cross-sectional study was carried out in 84 students, 54.1% men and 45.9% women with an age range between 10 and 17 years who were attending primary or secondary school education in a suburban town of high marginalization in Yucatan. Self-applicable Stunkard pictogram was used to record the body image perceptions. To calculate the body mass index (BMI) anthropometric measurements of weight and height were recorded, using a Tanita brand digital scale, TBC model and a stadiometer SECA 310 2 meters length. The cut-off points were those established by the World Health Organization. Results The findings regarding the perception of body image showed no significant concordance (k = 0.067, p <0.5); for women was a low value of k = 0.223, they perceive themselves as normal despite their low weight, and those with obesity underestimate their status. In the group of men, in cases of obesity, image and BMI are coincident while a body perception underestimates low weight. Conclusion It is important to take into the nutritional diagnosis, contents of emotional aspects as self-esteem and feelings that manifest teenagers about their body image for comprehensive preventive care.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA