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1.
Mol Psychiatry ; 27(4): 1920-1935, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35194166

RESUMO

The emerging understanding of gut microbiota as 'metabolic machinery' influencing many aspects of physiology has gained substantial attention in the field of psychiatry. This is largely due to the many overlapping pathophysiological mechanisms associated with both the potential functionality of the gut microbiota and the biological mechanisms thought to be underpinning mental disorders. In this systematic review, we synthesised the current literature investigating differences in gut microbiota composition in people with the major psychiatric disorders, major depressive disorder (MDD), bipolar disorder (BD) and schizophrenia (SZ), compared to 'healthy' controls. We also explored gut microbiota composition across disorders in an attempt to elucidate potential commonalities in the microbial signatures associated with these mental disorders. Following the PRISMA guidelines, databases were searched from inception through to December 2021. We identified 44 studies (including a total of 2510 psychiatric cases and 2407 controls) that met inclusion criteria, of which 24 investigated gut microbiota composition in MDD, seven investigated gut microbiota composition in BD, and 15 investigated gut microbiota composition in SZ. Our syntheses provide no strong evidence for a difference in the number or distribution (α-diversity) of bacteria in those with a mental disorder compared to controls. However, studies were relatively consistent in reporting differences in overall community composition (ß-diversity) in people with and without mental disorders. Our syntheses also identified specific bacterial taxa commonly associated with mental disorders, including lower levels of bacterial genera that produce short-chain fatty acids (e.g. butyrate), higher levels of lactic acid-producing bacteria, and higher levels of bacteria associated with glutamate and GABA metabolism. We also observed substantial heterogeneity across studies with regards to methodologies and reporting. Further prospective and experimental research using new tools and robust guidelines hold promise for improving our understanding of the role of the gut microbiota in mental and brain health and the development of interventions based on modification of gut microbiota.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Microbioma Gastrointestinal , Esquizofrenia , Encéfalo , Microbioma Gastrointestinal/fisiologia , Humanos
2.
Osteoporos Int ; 32(11): 2193-2203, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34043032

RESUMO

A growing body of evidence suggests that diet quality may predict muscle health. This study found that a "Traditional" dietary pattern predicted greater muscle mass, and an anti-inflammatory diet predicted greater muscle mass and better muscle function over 15 years. These findings reinforce the importance of optimising dietary behaviours for healthy ageing. INTRODUCTION: Research investigating the roles of individual nutrients in muscle health fails to account for the synergistic relationships between foods and nutrients. This study aimed to investigate the predictive value of diet quality and dietary patterns for muscle mass and function in men over a 15-year period. METHODS: This longitudinal study was conducted in 522 men from the Geelong Osteoporosis Study with complete dietary and muscle mass or muscle function data at both baseline and 15-year follow-up assessments. Dietary exposures were extracted from food frequency questionnaires and included the Australian Recommended Food Score, the Dietary Inflammatory Index (DII®), and three a posteriori dietary patterns: Plant-focused, Western, and Traditional (Anglo-Australian). Outcome variables included dual-energy X-ray absorptiometry-derived skeletal muscle index (SMI) and muscle function measured with the timed up-and-go (TUG) test. RESULTS: An anti-inflammatory diet and higher scores on a Traditional dietary pattern both predicted greater SMI ((B: -0.04 (95%CI -0.08, -0.00) kg/m2) and (B: 0.12 (95%CI 0.04, 0.20) kg/m2), respectively), while a pro-inflammatory diet predicted slower TUG (B: 0.11 (95%CI 0.001, 0.21) sec) over the 15-year follow-up period. These associations remained significant following adjustment for confounding variables. There were no associations observed for other dietary exposures. CONCLUSION: A Traditional dietary pattern higher in vegetables, wholegrain cereals, and animal protein was associated with greater skeletal muscle mass, and an anti-inflammatory diet, also rich in vegetables, fruit, and wholegrain cereals, was associated with greater skeletal muscle mass and better muscle function over 15 years.


Assuntos
Dieta , Verduras , Animais , Austrália/epidemiologia , Humanos , Estudos Longitudinais , Músculo Esquelético
3.
Allergy ; 72(8): 1222-1231, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28042676

RESUMO

BACKGROUND: Ecological evidence suggests vitamin D insufficiency (VDI) due to lower ambient ultraviolet radiation (UVR) exposure may be a risk factor for IgE-mediated food allergy. However, there are no studies relating directly measured VDI during early infancy to subsequent challenge-proven food allergy. OBJECTIVE: To prospectively investigate the association between VDI during infancy and challenge-proven food allergy at 1 year. METHODS: In a birth cohort (n = 1074), we used a case-cohort design to compare 25-hydroxyvitamin D3 (25(OH)D3 ) levels among infants with food allergy vs a random subcohort (n = 274). The primary exposures were VDI (25(OH)D3 <50 nM) at birth and 6 months of age. Ambient UVR and time in the sun were combined to estimate UVR exposure dose. IgE-mediated food allergy status at 1 year was determined by formal challenge. Binomial regression was used to examine associations between VDI, UVR exposure dose and food allergy and investigate potential confounding. RESULTS: Within the random subcohort, VDI was present in 45% (105/233) of newborns and 24% (55/227) of infants at 6 months. Food allergy prevalence at 1 year was 7.7% (61/786), and 6.5% (53/808) were egg-allergic. There was no evidence of an association between VDI at either birth (aRR 1.25, 95% CI 0.70-2.22) or 6 months (aRR 0.93, 95% CI 0.41-2.14) and food allergy at 1 year. CONCLUSIONS: There was no evidence that VDI during the first 6 months of infancy is a risk factor for food allergy at 1 year of age. These findings primarily relate to egg allergy, and larger studies are required.


Assuntos
Hipersensibilidade Alimentar/epidemiologia , Hipersensibilidade Alimentar/etiologia , Imunoglobulina E/imunologia , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia , Fatores Etários , Estudos de Casos e Controles , Estudos de Coortes , Dieta/efeitos adversos , Exposição Ambiental , Feminino , Humanos , Imunização , Lactente , Recém-Nascido , Masculino , Vigilância da População , Prevalência , Fatores de Risco , Raios Ultravioleta , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/etiologia
4.
Mol Psychiatry ; 21(5): 656-64, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26347317

RESUMO

Selective serotonin reuptake inhibitors (SSRIs) are the most commonly prescribed treatments for depression and, as a class of drugs, are among the most used medications in the world. Concern regarding possible effects of SSRI treatment on fetal development has arisen recently as studies have suggested a link between maternal SSRI use and an increase in birth defects such as persistent pulmonary hypertension, seizures and craniosynostosis. Furthermore, SSRI exposure in adults is associated with decreased bone mineral density and increased fracture risk, and serotonin receptors are expressed in human osteoblasts and osteoclasts. To determine possible effects of SSRI exposure on developing bone, we treated both zebrafish, during embryonic development, and human mesenchymal stem cells (MSCs), during differentiation into osteoblasts, with the two most prescribed SSRIs, citalopram and sertraline. SSRI treatment in zebrafish decreased bone mineralization, visualized by alizarin red staining and decreased the expression of mature osteoblast-specific markers during embryogenesis. Furthermore, we showed that this inhibition was not associated with increased apoptosis. In differentiating human MSCs, we observed a decrease in osteoblast activity that was associated with a decrease in expression of the osteoblast-specific genes Runx2, Sparc and Spp1, measured with quantitative real-time PCR (qRT-PCR). Similar to the developing zebrafish, no increase in expression of the apoptotic marker Caspase 3 was observed. Therefore, we propose that SSRIs inhibit bone development by affecting osteoblast maturation during embryonic development and MSC differentiation. These results highlight the need to further investigate the risks of SSRI use during pregnancy in exposing unborn babies to potential skeletal abnormalities.


Assuntos
Osso e Ossos/efeitos dos fármacos , Osso e Ossos/embriologia , Citalopram/toxicidade , Inibidores Seletivos de Recaptação de Serotonina/toxicidade , Sertralina/toxicidade , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Calcificação Fisiológica/efeitos dos fármacos , Calcificação Fisiológica/fisiologia , Cartilagem/efeitos dos fármacos , Cartilagem/embriologia , Células Cultivadas , Modelos Animais de Doenças , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Peixe-Zebra
6.
Prog Urol ; 23(9): 612-20, 2013 Jul.
Artigo em Francês | MEDLINE | ID: mdl-23830255

RESUMO

OBJECTIVE: To describe the main female sexual dysfunctions, their mechanisms, and the broad outlines of their therapeutic management. MATERIAL AND METHODS: Review of consensus conferences and published guidelines on this subject and a reflexion from our own clinical experience, in urogynaecological practice. RESULTS: Female sexual dysfunction is frequent and can present in different ways; pain, problems concerning desire and satisfaction. These symptoms can be associated with concomitant male sexual dysfunction. These symptoms can be managed by a gynaecologist if he/she is trained accordingly. Knowledge of this is essential for a gynaecologist in daily practice but also for an urologist treating both female urinary incontinence or pelvic prolapse and male sexual dysfunction. CONCLUSION: Women's sexual disorders can considerably affect the quality of life of the partner and the couple. As the patients hesitate to speak of such matters the clinician should begin the dialogue with simple open questions.


Assuntos
Disfunções Sexuais Fisiológicas/diagnóstico , Disfunções Sexuais Fisiológicas/terapia , Disfunções Sexuais Psicogênicas/diagnóstico , Disfunções Sexuais Psicogênicas/terapia , Algoritmos , Feminino , Humanos
8.
Osteoporos Int ; 21(10): 1715-22, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20052458

RESUMO

UNLABELLED: Methods: Leptin levels were measured in 103 consecutive women with anorexia nervosa. Results: Spine BMD and Z-score values were found to be significantly lower in the low tertile compared with the highest tertile. Duration of amenorrhea and leptin level accounted for 27% of the variance in lumbar spine BMD. INTRODUCTION: The purpose of this study was to assess leptin levels and other biological variables in a population of anorexia nervosa patients. METHODS: Leptin levels were measured consecutively in 103 women with anorexia nervosa (AN) with a mean age of 24.9 +/- 7.4 years. Osteodensitometry was also performed by dual energy X-ray absorptiometry (DXA). RESULTS: Spine bone mineral density (BMD) and Z-score values were found to be significantly lower in the low tertile compared with the highest tertile. Duration of amenorrhea and leptin level accounted for 27% of the variance in lumbar spine BMD. The mean leptin level was 3.9 +/- 4.6 ng/mL (normal values, 3.5-11 ng/mL). The distribution of leptin values was not a Gaussian distribution, and a log-transformed was therefore performed. A significant correlation was found between leptin level and spinal BMD (r = 0.3; p = 0.002); significant correlations were observed for both femoral neck and total hip BMDs. When leptin level values were divided into tertiles, spine BMD and Z-score values were found to be significantly lower in the lower tertile (p = 0.04 and p = 0.02) compared with the highest tertile. For femoral neck BMDs, the T-score was slightly lower between low and high tertile, but the difference was not statistically significant (p = 0.07). When multivariate analyses were performed, two independent factors which could possibly account for the variance in spinal BMDs were found. Duration of amenorrhea and leptin level accounted for 27% of the variance (p < 0.0001). CONCLUSION: The mechanisms underlying bone loss in AN patients remain unclear and complex, involving hypoestrogenia as well as nutritional factors such as insulin-like growth factor and leptin.


Assuntos
Anorexia Nervosa/complicações , Leptina/sangue , Osteoporose/etiologia , Absorciometria de Fóton/métodos , Adolescente , Adulto , Amenorreia/sangue , Amenorreia/etiologia , Anorexia Nervosa/sangue , Densidade Óssea/fisiologia , Feminino , Colo do Fêmur/fisiopatologia , Articulação do Quadril/fisiopatologia , Humanos , Vértebras Lombares/fisiopatologia , Osteoporose/sangue , Adulto Jovem
9.
Gynecol Obstet Fertil ; 36(3): 306-10, 2008 Mar.
Artigo em Francês | MEDLINE | ID: mdl-18337145

RESUMO

Up to now, there are only a few studies to have dealt with the psychosexual consequences of vulvar intraepithelial neoplasias (VINs) and their surgical treatment. Yet, these consequences cannot be ignored. The patients' daily experience is always complicated, especially because the disease--rightly or not--is assimilated to cancer, is a sexually transmissible infection, affects a part of the body with particular symbols, but also because today there are no certainties whatever on this subject. From the observation of patients followed by a team of specialists, this article aims to describe most frequent reactions, try to explain them, and consider what medical accompaniment and counsel might be proposed in these circumstances.


Assuntos
Carcinoma in Situ/psicologia , Neoplasias Vulvares/psicologia , Carcinoma in Situ/cirurgia , Feminino , Seguimentos , Humanos , Satisfação do Paciente , Resultado do Tratamento , Neoplasias Vulvares/cirurgia
10.
Gynecol Obstet Fertil ; 36(2): 190-199, 2008 Feb.
Artigo em Francês | MEDLINE | ID: mdl-18272417

RESUMO

Vulvar pathology is located at the border between dermatology and gynaecology. The gynaecologist is concerned by VIN (vulvar intraepithelial neoplasia) lesions as patients meet them for that problem. He makes distinction with dermatologic lesions so as to refer proper patients to dermatologists. A recent classification of VIN has a major interest. One individualizes two kinds of precancerous lesions. The first one is lichen sclerosis with dermatologic treatment by dermocorticoids and the other aetiology is HPV infection with frequent association with cervical localisation. Gynaecologists are more familiar with this second aetiology. Thus, they have to (i) check for VIN, (ii) know their appearance and how the diagnosis can be made by biopsy, (iii) precise the aetiology, (iv) appreciate the severity of the disease, (v) discuss which treatment is indicated: destruction or surgery.


Assuntos
Carcinoma in Situ/diagnóstico , Líquen Escleroso e Atrófico/diagnóstico , Infecções por Papillomavirus/diagnóstico , Líquen Escleroso Vulvar/diagnóstico , Neoplasias Vulvares/diagnóstico , Carcinoma in Situ/etiologia , Carcinoma in Situ/patologia , Carcinoma in Situ/virologia , Diagnóstico Diferencial , Feminino , Humanos , Líquen Escleroso e Atrófico/patologia , Infecções por Papillomavirus/patologia , Lesões Pré-Cancerosas , Índice de Gravidade de Doença , Líquen Escleroso Vulvar/patologia , Neoplasias Vulvares/etiologia , Neoplasias Vulvares/patologia , Neoplasias Vulvares/virologia
11.
Pediatr Obes ; 13(1): 46-53, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-27723247

RESUMO

BACKGROUND: Excess adiposity and adiposity-related inflammation are known risk factors for cardiovascular disease in adults; however, little is known regarding the determinants of adiposity-related inflammation at birth. OBJECTIVES: The aim of this study was to investigate the association between maternal pre-pregnancy BMI and newborn adiposity and inflammation. METHODS: Paired maternal (28-week gestation) and infant (umbilical cord) blood samples were collected from a population-derived birth cohort (Barwon Infant Study, n = 1074). Data on maternal comorbidities and infant birth anthropomorphic measures were compiled, and infant aortic intima-media thickness was measured by trans-abdominal ultrasound. In a selected subgroup of term infants (n = 161), matched maternal and cord lipids, high-sensitivity C-reactive protein (hsCRP) and maternal soluble CD14 were measured. Analysis was completed by using pairwise correlation and linear regression. Because of their non-normal distribution, pathology blood measures were log transformed prior to analysis. RESULTS: Maternal pre-pregnancy BMI was positively associated with increased birth weight (mean difference 17.8 g per kg m-2 , 95% CI 6.6 to 28.9; p = 0.002), newborn mean skin-fold thickness (mean difference 0.1 mm per kg m-2 , 95% CI 0.0 to 0.1; p < 0.001) and cord blood hsCRP (mean difference of 4.2% increase in hsCRP per kg m-2 increase in pre-pregnancy BMI, 95% CI 0.6 to 7.7%, p = 0.02), but not cord blood soluble CD14. Inclusion of maternal hsCRP as a covariate attenuated the associations between pre-pregnancy BMI and both newborn skin-fold thickness and cord blood hsCRP. CONCLUSION: Higher maternal pre-pregnancy BMI is associated with increased newborn adiposity and inflammation. These associations may be partially mediated by maternal inflammation during pregnancy.


Assuntos
Adiposidade , Peso ao Nascer , Índice de Massa Corporal , Inflamação/metabolismo , Adulto , Proteína C-Reativa/metabolismo , Espessura Intima-Media Carotídea , Feminino , Sangue Fetal/metabolismo , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Lipídeos/sangue , Masculino , Mães , Gravidez , Fatores de Risco , Dobras Cutâneas
13.
Cancer Res ; 45(10): 5106-13, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3896472

RESUMO

A clonal rat osteogenic sarcoma cell line, UMR 106-06, was used to study the effects of retinoic acid (RA) on its growth and morphology. Retinoic acid caused a reversible, time and dose-dependent inhibition of growth. RA-treated cells were larger, were more adherent to the substratum, and contained fewer mitotic figures. Half-maximal growth inhibition was observed at 10(-8) M. Among the naturally occurring retinoids, RA was clearly the most potent while the arotinoids, Ro 13-7410 and Ro 13-6298, were approximately 50 times more potent than was RA. A similar range of potencies was observed in the cloning efficiencies of the cells in soft agar. Fluorescence microscopy revealed that RA treatment increased the cellular content and organization of F-actin fibers. Ultrastructural changes include decreased chromatin dispersion and increased number of nucleoli per nucleus, decreased rough endoplasmic reticulum, decreased electron density and number of mitochondria, and increased formation of microfilaments and microtubules. These results identify this clonal cell line, which has been extensively characterized as the malignant counterpart of the normal osteoblast, as a target for vitamin A action.


Assuntos
Citoesqueleto/ultraestrutura , Osteoblastos/efeitos dos fármacos , Osteossarcoma/patologia , Retinoides/farmacologia , Actinas/análise , Animais , Células Cultivadas , Citoesqueleto/efeitos dos fármacos , Microscopia Eletrônica , Microscopia de Contraste de Fase , Osteoblastos/ultraestrutura , Osteossarcoma/ultraestrutura , Ratos , Tubulina (Proteína)/análise
14.
Rev Med Brux ; 27 Spec No: Sp9-12, 2006.
Artigo em Francês | MEDLINE | ID: mdl-21818886

RESUMO

A Convention signed by the academic and political Authorities of the University of Brussels and IRIS (Brussels public health institutions) allows the creation of an Interhospital Department of Pediatric Surgery. The pediatric surgeons of the different hospitals have now the opportunity to organise a large cooperation on a clinical, research and teaching basis.


Assuntos
Comportamento Cooperativo , Unidades Hospitalares/organização & administração , Bélgica , Hospitais Pediátricos , Hospitais Universitários , Humanos
15.
Rev Med Brux ; 27 Spec No: Sp69-73, 2006.
Artigo em Francês | MEDLINE | ID: mdl-21818896

RESUMO

The department of pediatric uro-nephrology was created in 1977 in Brugmann hospital. Since then, various sectors have been developed including: hemodialysis and peritoneal dialysis, kidney transplantation, urological and genital surgery, antenatal screening and rapid management of uronephropathies, treatment of voiding dysfunction and neurogenic bladder, management of tubular and glomerular diseases. The progress in genetics, medical imaging, obstetrics, neonatology and surgery has allowed us to take care of our young patients within a multidisciplinary framework. The most original contributions of the department are related to the performance of combined liver-kidney transplantation in primary hyperoxaluria, to the determination of the natural history of several congenital anomalies of the kidney and urinary tract, to the assessment of the role of genetical mutations on tubular and glomerular diseases, to the usefulness of radioisotopic tracers in the measurement of renal function in infants, and to the study of experimental tolerization of


Assuntos
Unidades Hospitalares , Nefropatias/terapia , Doenças Urológicas/terapia , Bélgica , Criança , Hospitais Pediátricos , Hospitais Universitários , Humanos , Nefropatias/epidemiologia , Doenças Urológicas/epidemiologia
16.
Gynecol Obstet Fertil ; 44(6): 363-7, 2016 Jun.
Artigo em Francês | MEDLINE | ID: mdl-27216956

RESUMO

Endometriosis, defined by the presence of endometrial tissue outside the uterine cavity, is a common but often under diagnosed pathology. The clinical manifestations are varied (chronic pelvic pain, urinary or gastrointestinal symptoms) and can sometimes be very frustrated, delaying the diagnosis. This delay in diagnosis can be a high source of stress responsible for an important psychological impact in these patients, having a sense of misunderstanding and neglect of the medical profession. This climate of stress and anxiety can cause alteration of behavior including sexual disorders. In addition, endometriosis can be revealed as part of an infertility evaluation, and the patient and the couple can already be affected by this situation. The clinical and psychological impact of endometriosis inevitably leads to an impairment of patient's quality of life and sexuality. The objective of this article is to show the psychological consequences of endometriosis and its impact on sexuality, in order to highlight this essential aspect for a comprehensive care of patients.


Assuntos
Endometriose/psicologia , Sexologia , Sexualidade/psicologia , Endometriose/diagnóstico , Endometriose/terapia , Feminino , Humanos , Infertilidade Feminina , Dor Pélvica , Qualidade de Vida
17.
Transl Psychiatry ; 6: e765, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-27023171

RESUMO

Compelling evidence suggests that maternal mental health in pregnancy can influence fetal development. The imprinted genes, insulin-like growth factor 2 (IGF2) and H19, are involved in fetal growth and each is regulated by DNA methylation. This study aimed to determine the association between maternal mental well-being during pregnancy and differentially methylated regions (DMRs) of IGF2 (DMR0) and the IGF2/H19 imprinting control region (ICR) in newborn offspring. Maternal depression, anxiety and perceived stress were assessed at 28 weeks of pregnancy in the Barwon Infant Study (n=576). DNA methylation was measured in purified cord blood mononuclear cells using the Sequenom MassArray Platform. Maternal anxiety was associated with a decrease in average ICR methylation (Δ=-2.23%; 95% CI=-3.68 to -0.77%), and across all six of the individual CpG units in anxious compared with non-anxious groups. Birth weight and sex modified the association between prenatal anxiety and infant methylation. When stratified into lower (⩽3530 g) and higher (>3530 g) birth weight groups using the median birth weight, there was a stronger association between anxiety and ICR methylation in the lower birth weight group (Δ=-3.89%; 95% CI=-6.06 to -1.72%), with no association in the higher birth weight group. When stratified by infant sex, there was a stronger association in female infants (Δ=-3.70%; 95% CI=-5.90 to -1.51%) and no association in males. All the linear regression models were adjusted for maternal age, smoking and folate intake. These findings show that maternal anxiety in pregnancy is associated with decreased IGF2/H19 ICR DNA methylation in progeny at birth, particularly in female, low birth weight neonates. ICR methylation may help link poor maternal mental health and adverse birth outcomes, but further investigation is needed.


Assuntos
Ansiedade/genética , Metilação de DNA , Depressão/genética , Sangue Fetal/metabolismo , Fator de Crescimento Insulin-Like II/genética , Complicações na Gravidez/genética , RNA Longo não Codificante/metabolismo , Estresse Psicológico/genética , Adulto , Ansiedade/metabolismo , Estudos de Coortes , Depressão/metabolismo , Feminino , Humanos , Recém-Nascido , Fator de Crescimento Insulin-Like II/metabolismo , Modelos Lineares , Masculino , Gravidez , Complicações na Gravidez/metabolismo , Estudos Prospectivos , Estresse Psicológico/metabolismo
18.
Endocrinology ; 139(3): 1258-67, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9492061

RESUMO

Although estrogen is important in human skeletal homeostasis, the major target cell in bone is unknown. Estrogen receptors (ER) have been demonstrated in osteoblasts and bone marrow stromal cells, but their presence in osteoclasts remains controversial because completely pure preparations have not been available. We have examined expression of ER-alpha and ER-beta messenger RNA (mRNA) by RT-PCR in samples from human giant cell tumor of bone (GCT), including: whole tumor, cultured mononuclear cells, and a pure osteoclast population obtained by microisolation. Whole tumor expressed both ER-alpha and calcitonin receptor (CTR) mRNA and apparently lower levels of ER-beta mRNA. Passaged cultures of tumor mononuclear stromal cells also expressed ER-alpha and low ER-beta but not CTR mRNA. In pure preparations of microisolated osteoclasts, expression of ER-alpha or ER-beta mRNA was not detected, whereas expression of CTR mRNA was readily identified. Microisolated GCT mononuclear cells expressed ER-alpha, but no detectable CTR mRNA. Fluorescence in situ hybridization (FISH) using an ER-alpha riboprobe demonstrated strong signal in the mononuclear cells but multinucleated osteoclasts showed no detectable signal. In contrast, CTR mRNA was detected in multinucleated osteoclasts but not in stromal-like tumor cells by FISH. 17Beta-estradiol consistently showed no effect on bone resorbing activity of osteoclasts from GCT cultured on cortical bone, although calcitonin was a potent inhibitor. These findings indicate that significant expression of ER does not occur in osteoclasts derived from human GCT and suggest that estrogen effects are mediated by other cells of the bone environment.


Assuntos
Neoplasias Ósseas/química , Tumores de Células Gigantes/química , Osteoclastos/química , Receptores de Estrogênio/análise , Células Cultivadas , Humanos , Hibridização in Situ Fluorescente , RNA Mensageiro/análise , Receptores da Calcitonina/genética , Receptores de Estrogênio/genética
19.
FEBS Lett ; 463(3): 295-300, 1999 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-10606741

RESUMO

Although the important roles of RANK/RANKL in osteoclastogenesis have been established, their roles in the regulation of mature osteoclasts remain uncertain. Microisolation has been used to obtain pure populations of rat and human osteoclasts for RT-PCR analysis. RANK and calcitonin receptor mRNA was detected in all the samples whereas OPG and ALP mRNA was not present in any. RANKL mRNA was detected in two of eight rat and one of four human samples. Treatment of osteoclasts with soluble RANKL resulted in translocation of NF-kappaB to the nucleus and elevation of cytosolic and nuclear calcium levels. We have shown that RANK is highly expressed in mature osteoclasts and that its stimulation by RANKL results in activation of NF-kappaB and calcium signalling.


Assuntos
Osteoclastos/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Animais , Sinalização do Cálcio , Proteínas de Transporte/genética , Proteínas de Transporte/farmacologia , Núcleo Celular/metabolismo , Regulação da Expressão Gênica , Humanos , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/farmacologia , Microscopia Confocal , NF-kappa B/metabolismo , Ligante RANK , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar , Receptor Ativador de Fator Nuclear kappa-B , Receptores do Fator de Necrose Tumoral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição RelA
20.
Bone ; 19(2): 137-42, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8853857

RESUMO

Zinc is an important element in biology yet little is understood of its role in bone cell metabolism and function. This study examined the effects of zinc on osteoclast (OC) function in cultures derived from neonatal rats and in cocultures of OC and UMR 106-01 osteoblast-like cells (UMR/OC cocultures). Treatment with zinc (10(-12)-10(-4) mol/L) had no effect on either bone resorption or the number of multinucleate cells positive for tartrate-resistant acid phosphatase (TRACP + ve MNC) in OC cultured for 24 h on bone slices. However, in UMR/OC cocultures, 10(-4) mol/L zinc (but not lower concentrations) decreased resorption pit formation by approximately 50% and increased TRACP + ve MNC number by approximately 40%. When osteoblast-like cells were pretreated with zinc prior to, but not during, coculture with OC, effects on TRACP + ve MNC and pit number persisted, although the effect was reduced. Zinc treatment also inhibited resorption and stimulated TRACP and calcitonin receptor (CTR) + ve MNC numbers in long-term (96-120 h) UMR/OC cocultures. Our results indicate that zinc increases TRACP + ve CTR + ve MNC numbers yet inhibits bone-resorbing activity, and that these effects are dependent on the presence of osteoblastic cells. Zinc is abundant in bone and may act as a local regulator of bone cells.


Assuntos
Reabsorção Óssea/prevenção & controle , Osteoblastos/fisiologia , Osteoclastos/efeitos dos fármacos , Zinco/farmacologia , Fosfatase Ácida/metabolismo , Animais , Animais Recém-Nascidos , Autorradiografia , Contagem de Células/efeitos dos fármacos , Núcleo Celular , Células Cultivadas , Técnicas de Cocultura , Isoenzimas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores da Calcitonina/metabolismo , Fosfatase Ácida Resistente a Tartarato , Células Tumorais Cultivadas
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