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1.
J Clin Endocrinol Metab ; 106(7): e2656-e2663, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-33686417

RESUMO

CONTEXT: Primary ovarian insufficiency (POI) is defined by menopause before 40 years of age. POI prevalence is higher among women with autoimmune Addison's disease (AAD) than in the general population, but their clinical characteristics are insufficiently studied. OBJECTIVE: To assess the prevalence of POI in a large cohort of women with AAD and describe clinical, immunological, and genetic characteristics. METHODS: An observational population-based cohort study of the Norwegian National Addison Registry. The Norwegian Prescription Database was used to assess prescription of menopausal hormone replacement therapy (HRT). A total of 461 women with AAD were studied. The primary outcome measure was prevalence of POI. Secondary outcomes were clinical characteristics, autoantibodies, and genome-wide single nucleotide polymorphism variation. RESULTS: The prevalence of POI was 10.2% (47/461) and one-third developed POI before 30 years of age. POI preceded or coincided with AAD diagnosis in more than half of the women. The prevalence of concomitant autoimmune diseases was 72%, and AAD women with POI had more autoantibodies than AAD women without (≥2 autoantibodies in 78% vs 25%). Autoantibodies against side-chain cleavage enzyme (SCC) had the highest accuracy with a negative predictive value for POI of 96%. HRT use was high compared to the age adjusted normal population (11.3 % vs 0.7%). CONCLUSION: One in 10 women with AAD have POI. Autoantibodies against SCC are the most specific marker for autoimmune POI. We recommend testing women with AAD <40 years with menstrual disturbances or fertility concerns for autoantibodies against SCC.


Assuntos
Doença de Addison/genética , Doença de Addison/imunologia , Menopausa Precoce/genética , Menopausa Precoce/imunologia , Insuficiência Ovariana Primária/epidemiologia , Doença de Addison/complicações , Adulto , Autoanticorpos/sangue , Autoanticorpos/imunologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Feminino , Terapia de Reposição Hormonal/estatística & dados numéricos , Humanos , Menopausa Precoce/sangue , Noruega/epidemiologia , Polimorfismo de Nucleotídeo Único , Valor Preditivo dos Testes , Prevalência , Insuficiência Ovariana Primária/genética , Insuficiência Ovariana Primária/imunologia , Sistema de Registros
2.
Nat Commun ; 11(1): 3588, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32680985

RESUMO

Tumors subvert immune cell function to evade immune responses, yet the complex mechanisms driving immune evasion remain poorly understood. Here we show that tumors induce de novo steroidogenesis in T lymphocytes to evade anti-tumor immunity. Using a transgenic steroidogenesis-reporter mouse line we identify and characterize de novo steroidogenic immune cells, defining the global gene expression identity of these steroid-producing immune cells and gene regulatory networks by using single-cell transcriptomics. Genetic ablation of T cell steroidogenesis restricts primary tumor growth and metastatic dissemination in mouse models. Steroidogenic T cells dysregulate anti-tumor immunity, and inhibition of the steroidogenesis pathway is sufficient to restore anti-tumor immunity. This study demonstrates T cell de novo steroidogenesis as a mechanism of anti-tumor immunosuppression and a potential druggable target.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Melanoma/imunologia , Esteroides/imunologia , Animais , Linfócitos T CD4-Positivos/metabolismo , Linhagem Celular Tumoral , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Humanos , Evasão da Resposta Imune , Melanoma/genética , Melanoma/metabolismo , Camundongos , Camundongos Knockout , Esteroides/biossíntese
3.
Nat Commun ; 7: 10213, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26750596

RESUMO

Effector CD8(+) T cells convert from IFN-γ(+) (Tc1) to IL-13(+) (Tc2) cells in the presence of IL-4. Underlying regulatory mechanisms are not fully defined. Here, we show that addition of 1,25D3, the active form of vitamin D3, during CD8(+) T-cell differentiation prevents IL-4-induced conversion to IL-13-producers. Transfer of 1,25D3-treated CD8(+) T cells into sensitized and challenged CD8(+)-deficient recipients fails to restore development of lung allergic responses. 1,25D3 alters vitamin D receptor (VDR) recruitment to the Cyp11a1 promoter in vitro and in vivo in the presence of IL-4. As a result, protein levels and enzymatic activity of CYP11A1, a steroidogenic enzyme regulating CD8(+) T-cell conversion, are decreased. An epistatic effect between CYP11A1 and VDR polymorphisms may contribute to the predisposition to childhood asthma. These data identify a role for 1,25D3 in the molecular programming of CD8(+) T-cell conversion to an IL-13-secreting phenotype through regulation of steroidogenesis, potentially governing asthma susceptibility.


Assuntos
Asma/imunologia , Calcitriol/imunologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Receptores de Calcitriol/imunologia , Linfócitos T Citotóxicos/imunologia , Adolescente , Transferência Adotiva , Alérgenos , Animais , Asma/genética , Asma/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Calcitriol/metabolismo , Estudos de Casos e Controles , Criança , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Imunoprecipitação da Cromatina , Simulação por Computador , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Predisposição Genética para Doença , Humanos , Immunoblotting , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-13/imunologia , Interleucina-13/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Ovalbumina , Polimorfismo de Nucleotídeo Único , Pregnenolona/metabolismo , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
4.
PLoS One ; 10(11): e0143458, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26618927

RESUMO

Canine hypoadrenocorticism likely arises from immune-mediated destruction of adrenocortical tissue, leading to glucocorticoid and mineralocorticoid deficiency. In humans with autoimmune Addison's disease (AAD) or autoimmune polyendocrine syndrome (APS), circulating autoantibodies have been demonstrated against enzymes associated with adrenal steroid synthesis. The current study investigates autoantibodies against steroid synthesis enzymes in dogs with spontaneous hypoadrenocorticism. Coding regions of canine CYP21A2 (21-hydroxylase; 21-OH), CYP17A1 (17-hydroxylase; 17-OH), CYP11A1 (P450 side-chain cleavage enzyme; P450scc) and HSD3B2 (3ß hydroxysteroid dehydrogenase; 3ßHSD) were amplified, cloned and expressed as 35S-methionine radiolabelled recombinant protein. In a pilot study, serum samples from 20 dogs with hypoadrenocorticism and four unaffected control dogs were screened by radio-immunoprecipitation assay. There was no evidence of reactivity against 21-OH, 17-OH or 3ßHSD, but five dogs with hypoadrenocorticism showed immunoreactivity to P450scc compared with controls. Serum samples were subsequently obtained from 213 dogs diagnosed with hypoadrenocorticism and 110 dogs from a hospital control population. Thirty control dogs were randomly selected to establish a threshold for antibody positivity (mean + 3 × standard deviation). Dogs with hypoadrenocorticism were more likely to be P450scc autoantibody positive than hospital controls (24% vs. 1.2%, respectively; p = 0.0016). Sex was significantly associated with the presence of P450scc autoantibodies in the case population, with 30% of females testing positive compared with 17% of males (p = 0.037). Significant associations with breed (p = 0.015) and DLA-type (DQA1*006:01 allele; p = 0.017) were also found. This cross-sectional study indicates that P450scc autoantibodies are present in a proportion of dogs affected with hypoadrenocorticism.


Assuntos
Doença de Addison/sangue , Autoanticorpos/sangue , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Doença de Addison/veterinária , Animais , Autoanticorpos/imunologia , Estudos de Casos e Controles , Cães , Feminino , Masculino
5.
Sci Signal ; 7(314): ra20, 2014 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-24570488

RESUMO

Intestinal crypt epithelial cells synthesize glucocorticoids, steroid hormones that protect against inflammatory bowel disease. To investigate how intestinal glucocorticoids are regulated during chronic inflammation, we induced chronic colitis in mice by exposing them to the chemical dextran sulfate sodium (DSS). We found that intestinal glucocorticoid secretion and expression of the genes Cyp11a1 and Cyp11b1 (which encode enzymes that synthesize glucocorticoids) were initially stimulated, but declined during the chronic phase, whereas tumor necrosis factor (TNF) and inflammatory cytokines secreted by T helper type 1 (TH1) and TH17 cells continuously increased in abundance in the inflamed colon. This suggested that inadequate intestinal glucocorticoid synthesis is a feature of chronic intestinal inflammation. We screened for cytokines that regulated intestinal glucocorticoid synthesis and found that TNF suppressed corticosterone secretion and Cyp11a1 and Cyp11b1 expression in an intestinal crypt epithelial cell line. TNF suppressed steroidogenesis by activating the transcription factors c-Jun and nuclear factor κB (NF-κB), which both interacted with the transcription factor NR5A2 and repressed Cyp11a1 reporter activity. This repression was relieved by expression of a dominant-negative form of c-Jun amino-terminal kinase 1 (JNK1), inhibitor of NF-κB, or by a JNK inhibitor. Furthermore, the dominant-negative TNF inhibitor XPro1595 inhibited c-Jun and NF-κB activation in mice, restored intestinal Cyp11a1 and Cyp11b1 expression, reduced colonic cell death, and rescued chronic colitis caused by DSS. Thus, during chronic colitis, TNF suppresses intestinal steroidogenic gene expression by inhibiting the activity of NR5A2, thus decreasing glucocorticoid synthesis and sustaining chronic inflammation.


Assuntos
Colite/metabolismo , Glucocorticoides/biossíntese , Mucosa Intestinal/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Linhagem Celular , Enzima de Clivagem da Cadeia Lateral do Colesterol/biossíntese , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Doença Crônica , Colite/induzido quimicamente , Colite/genética , Colite/imunologia , Colite/patologia , Corticosterona/biossíntese , Corticosterona/genética , Corticosterona/imunologia , Sulfato de Dextrana/toxicidade , Regulação Enzimológica da Expressão Gênica/genética , Regulação Enzimológica da Expressão Gênica/imunologia , Glucocorticoides/genética , Glucocorticoides/imunologia , Humanos , Intestinos/imunologia , Intestinos/patologia , Camundongos , Proteína Quinase 8 Ativada por Mitógeno/genética , Proteína Quinase 8 Ativada por Mitógeno/imunologia , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , NF-kappa B/genética , NF-kappa B/imunologia , NF-kappa B/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/imunologia , Esteroide 11-beta-Hidroxilase/biossíntese , Esteroide 11-beta-Hidroxilase/genética , Esteroide 11-beta-Hidroxilase/imunologia , Células Th1/imunologia , Células Th1/metabolismo , Células Th1/patologia , Células Th17/imunologia , Células Th17/metabolismo , Células Th17/patologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
6.
Clin Exp Allergy ; 44(2): 197-211, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24447082

RESUMO

BACKGROUND: Glucocorticoids are used to treat allergic rhinitis, but the mechanisms by which they induce disease remission are unclear. 11ß-hydroxysteroid dehydrogenase (11ß-HSD) is a tissue-specific regulator of glucocorticoid responses, inducing the interconversion of inactive and active glucocorticoids. OBJECTIVE: We analysed the expression and distribution patterns of 11ß-HSD1, 11ß-HSD2, and steroidogenic enzymes in normal and allergic nasal mucosa, and cytokine-driven regulation of their expression. The production levels of cortisol in normal, allergic nasal mucosa and in cultured epithelial cells stimulated with cytokines were also determined. METHODS: The expression levels of 11ß-HSD1, 11ß-HSD2, steroidogenic enzymes (CYP11B1, CYP11A1), and cortisol in normal, mild, and moderate/severe persistent allergic nasal mucosa were assessed by real-time PCR, Western blot, immunohistochemistry, and ELISA. The expression levels of 11ß-HSD1, 11ß-HSD2, CYP11B1, CYP11A1, and cortisol were also determined in cultured nasal epithelial cell treated with IL-4, IL-5, IL-13, IL-17A, and IFN-γ. Conversion ratio of cortisone to cortisol was evaluated using siRNA technique, 11ß-HSD1 inhibitor, and the measurement of 11ß-HSD1 activity. RESULTS: The expression levels of 11ß-HSD1, CYP11B1, and cortisol were up-regulated in mild and moderate/severe persistent allergic nasal mucosa. By contrast, 11ß-HSD2 expression was decreased in allergic nasal mucosa. In cultured epithelial cells treated with IL-4, IL-5, IL-13, and IL-17A, 11ß-HSD1 expression and activity increased in parallel with the expression levels of CYP11B1 and cortisol, but the production of 11ß-HSD2 decreased. CYP11A1 expression level was not changed in allergic nasal mucosa or in response to stimulation with cytokines. SiRNA technique or the measurement of 11ß-HSD1 activity showed that nasal epithelium activates cortisone to cortisol in a 11ß-HSD-dependent manner. CONCLUSIONS AND CLINICAL RELEVANCE: These results indicate that the localized anti-inflammatory effects of glucocorticoids are regulated by inflammatory cytokines, which can modulate the expression of 11ß-HSD1, 11ß-HSD2, and CYP11B1, and by the intracellular concentrations of bioactive glucocorticoids.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/biossíntese , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/biossíntese , Citocinas/biossíntese , Mucosa Nasal/metabolismo , Rinite Alérgica Perene/metabolismo , Células Th2/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/imunologia , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/imunologia , Adulto , Enzima de Clivagem da Cadeia Lateral do Colesterol/biossíntese , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Citocinas/imunologia , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/farmacocinética , Humanos , Hidrocortisona/imunologia , Hidrocortisona/metabolismo , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/imunologia , Mucosa Nasal/patologia , Rinite Alérgica Perene/tratamento farmacológico , Rinite Alérgica Perene/imunologia , Rinite Alérgica Perene/patologia , Esteroide 11-beta-Hidroxilase/biossíntese , Esteroide 11-beta-Hidroxilase/imunologia , Células Th2/imunologia , Células Th2/patologia
7.
Int J Dev Biol ; 55(6): 619-25, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21948710

RESUMO

To understand the mechanism of sex differentiation in the protogynous Malabar grouper Epinephelus malabaricus, we performed an immunohistochemical investigation of the expression of three steroidogenic enzymes, cholesterol-side-chain-cleavage enzyme (CYP11a), aromatase (CYP19a1a), and cytochrome P45011beta-hydroxylase (CYP11b), in the gonads during ovarian differentiation. Strong positive immunoreactivity against CYP11a, the key enzyme of steroidogenesis, and CYP19a1a which is essential for estrogen (17beta-estradiol) production, appeared first in the somatic cells surrounding gonial germ cells in undifferentiated gonads and throughout ovarian differentiation. However, positive immunoreactivity against CYP11b, which is important for androgen (11-ketotestosterone) production, first appeared in the cluster of somatic cells in the ovary tunica near the dorsal blood vessel after differentiation. CYP19a1a and CYP11b did not co-localize in any cells. These results indicate that there are two types of steroid-producing cells, estrogen-producing cells and androgen-producing cells, in the gonads of this fish, and they are distributed differently, suggesting that these cells are derived from different somatic cells. Estrogen-producing cells appeared prior to ovarian differentiation, while androgen-producing cells were first detected after ovarian differentiation. These results suggest that endogenous estrogen is involved in ovarian differentiation.


Assuntos
Estradiol/biossíntese , Ovário/citologia , Perciformes/crescimento & desenvolvimento , Testosterona/análogos & derivados , Animais , Aromatase/biossíntese , Aromatase/metabolismo , Diferenciação Celular/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/biossíntese , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Feminino , Ovário/enzimologia , Ovário/metabolismo , Perciformes/metabolismo , Diferenciação Sexual/genética , Esteroide 11-beta-Hidroxilase/biossíntese , Esteroide 11-beta-Hidroxilase/metabolismo , Esteroides/biossíntese , Testosterona/biossíntese
8.
J Clin Endocrinol Metab ; 96(8): E1255-61, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21677034

RESUMO

DESIGN: The design of the study was to investigate the prevalence of the following: 1) premature ovarian failure (POF) in patients with autoimmune Addison's disease (AD); 2) steroid-producing cell antibodies (StCA) and steroidogenic enzymes (17α-hydroxylase autoantibodies and P450 side-chain cleavage enzyme autoantibodies) in patients with or without POF; and 3) the value of these autoantibodies to predict POF. PATIENTS: The study included 258 women: 163 with autoimmune polyendocrine syndrome type 2 (APS-2), 49 with APS-1, 18 with APS-4, and 28 with isolated AD. METHODS: StCA were measured by an immunofluorescence technique and 17α-hydroxylase autoantibodies and P450 side-chain cleavage enzyme autoantibodies by immunoprecipitation assays. RESULTS: Fifty-two of 258 women with AD (20.2%) had POF. POF was diagnosed in 20 of 49 (40.8%) with APS-1, six of 18 (33.3%) with APS-4, 26 of 163 (16%) with APS-2, and none of 28 with isolated AD. In patients with APS-1 and APS-4, POF developed after AD, whereas it preceded AD in patients with APS-2. StCA were detected in 31 of 43 with POF (72%) and 51 of 198 without POF (25.7%). StCA were present in 22 of 38 with APS-1 (57.9%) (11 of 13 with POF); in five of 13 with APS-4 (38.5%) (three of four with POF); in 53 of 162 with APS-2 (32.7%) (17 of 26 with POF), and in one of 28 isolated AD patients (3.6%). Twelve of 13 patients with POF with a duration less than 5 yr (92.3%) and 18 of 25 with duration longer than 5 yr (72%) were StCA positive. Twenty-eight of 31 with POF (90.3%) were positive for at least one steroidogenic antibody. Forty-one women with AD less than 40 yr were followed up for a mean period of 9 yr. Eight of 21 women (38%) positive or seroconverted for steroidogenic autoantibodies developed POF at a mean age of 23 yr (six with APS-1, one with APS-2, and one with APS-4), and none of the 20 patients negative for steroidogenic autoantibodies developed POF. CONCLUSIONS: This study indicates that AD is frequently associated with POF and that steroidogenic antibodies are markers of patients with POF. Steroidogenic autoantibodies are predictive markers of POF in patients with AD.


Assuntos
Doença de Addison , Insuficiência Ovariana Primária , Doença de Addison/epidemiologia , Doença de Addison/genética , Doença de Addison/imunologia , Adolescente , Adulto , Autoanticorpos/sangue , Criança , Pré-Escolar , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Feminino , Seguimentos , Antígenos HLA-DR/genética , Cadeias HLA-DRB1 , Humanos , Pessoa de Meia-Idade , Poliendocrinopatias Autoimunes/epidemiologia , Poliendocrinopatias Autoimunes/genética , Poliendocrinopatias Autoimunes/imunologia , Valor Preditivo dos Testes , Prevalência , Insuficiência Ovariana Primária/epidemiologia , Insuficiência Ovariana Primária/genética , Insuficiência Ovariana Primária/imunologia , Esteroide 17-alfa-Hidroxilase/imunologia , Adulto Jovem
9.
Eur J Endocrinol ; 163(2): 309-17, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20498138

RESUMO

OBJECTIVE: Steroid-producing cell autoantibodies (SCAs) directed against 21-hydroxylase autoantibodies (21OHAbs), 17alpha-hydroxylase autoantibodies (17OHAb), and cholesterol side-chain cleavage enzyme (side-chain cleavage autoantibodies, P450sccAb) characterize autoimmune primary ovarian insufficiency (SCA-POI). The aim of the study was to analyze IgG subclass specificity of autoantibodies related to adrenal and ovarian autoimmunity. DESIGN: We studied 29 women with SCA-POI, 30 women with autoimmune Addison's disease (AAD) without POI, and 14 patients with autoimmune polyendocrine syndrome type 1 (APS1). 21OHAb isotypes were also analyzed in 14 subjects with preclinical AAD. Samples from 30 healthy women served as control group to determine the upper level of normality in the isotype assays. METHODS: Immunoradiometric assays with IgG subclass-specific secondary antibodies. RESULTS: In 21OHAb-positive sera, IgG1 isotype was detected in 90% SCA-POI and non-POI AAD sera and 67% APS1 patients. IgG1 isotype was found in 69% 17OHAb-positive SCA-POI and 100% 17OHAb-positive APS1 sera, and in 60% P450sccAb-positive SCA-POI and 80% P450sccAb-positive APS1 sera. For 21OHAb, IgG4 isotype was detected in 17% SCA-POI, 7% non-POI AAD, and 8% APS1 sera. None of the 17OHAb-positive sera was positive for IgG4. In P450sccAb-positive sera, 15% POI and 20% APS1 sera were positive for IgG4. Two 21OHAb-positive SCA-POI (7%), one 21OHAb-positive AAD (3%), three P450sccAb-positive SCA-POI (15%), and two P450sccAb-positive APS1 (20%) sera were positive for IgG4, in the absence of IgG1. All preclinical AAD sera resulted as positive for IgG1-21OHAb, but not for IgG4-21OHAb. CONCLUSIONS: The autoantibody responses in POI and AAD are IgG1 dominated, which suggests a predominant Th1 response. Selective IgG4 isotype specificity identified a small subset of patients with Th2-oriented response.


Assuntos
Doença de Addison/imunologia , Autoanticorpos/imunologia , Imunoglobulina G/imunologia , Poliendocrinopatias Autoimunes/imunologia , Insuficiência Ovariana Primária/imunologia , Adolescente , Adulto , Idoso , Distribuição de Qui-Quadrado , Criança , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Feminino , Humanos , Hipogonadismo/imunologia , Ensaio Imunorradiométrico , Infertilidade/imunologia , Masculino , Pessoa de Meia-Idade , Esteroide 21-Hidroxilase/imunologia
10.
Brain Behav Immun ; 20(5): 460-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16256304

RESUMO

Several lines of evidence indicate that cytokines can affect adrenal function. To date most of these cytokines have been shown to be pro-inflammatory, such as interleukin (IL)-1, tumor necrosis factor (TNFalpha), and IL-6. However, we have previously shown that IL-10-/- (IL-10 knockout) mice have higher serum corticosterone levels than IL-10+/+ (wild type) mice following acute immune and physiologic stress, implying that IL-10, an anti-inflammatory cytokine, regulates glucocorticoid synthesis in a negative manner. Here, we show that IL-10 knockout mice produce more corticosterone under basal conditions as well (shown by ELISA). We further support this contention by showing that in Y-1 adrenocortical cells IL-10 inhibits steroid production (StAR) (measured by the production of the corticosterone precursor, progesterone), the expression of steroidogenic acute regulatory protein (semi-quantitative RT-PCR), as well as the activity of the proximal steroidogenic enzymes P450scc and/or 3beta-hydroxysteroid dehydrogenase (3beta-HSD) (measured by progesterone production in 22(R)-hydroxycholesterol-treated cells). Interestingly, all of the above-mentioned effects of IL-10 occur through its inhibition of ACTH effects, but not by IL-10 alone. Furthermore, immunocytochemistry data shows that the region of the adrenal gland responsible for the vast majority of corticosterone synthesis, the zona fasciculata, predominantly expresses the IL-10 receptor 1 (IL-10R1), with little expression in the zona glomerulosa and reticularis. These data demonstrate that IL-10 could play an important role in the regulation of glucocorticoid biosynthesis and in maintenance of homeostasis and immunity during periods of stress.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Corticosterona/metabolismo , Interleucina-10/metabolismo , Receptores de Interleucina/metabolismo , Zona Fasciculada/metabolismo , 3-Hidroxiesteroide Desidrogenases/imunologia , 3-Hidroxiesteroide Desidrogenases/metabolismo , Hormônio Adrenocorticotrópico/imunologia , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Corticosterona/imunologia , Regulação da Expressão Gênica , Interleucina-10/genética , Interleucina-10/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfoproteínas/imunologia , Fosfoproteínas/metabolismo , RNA/análise , Receptores de Interleucina/genética , Receptores de Interleucina/imunologia , Receptores de Interleucina-10 , Distribuição Tecidual , Células Tumorais Cultivadas , Zona Fasciculada/citologia , Zona Fasciculada/imunologia
11.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 21(2): 198-201, 2005 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15766405

RESUMO

AIM: To prepare rabbit anti-rat P450scc antibody, and to detect the expression of rP450scc in rat brain tissue and nerve cells. METHODS: An eight-branched polypeptide, rP450scc-16 was synthesized using solid phase synthesis (Fmoc) method. A Newzealand rabbit was immunized with rP450scc-16 and the serum was separated from the whole blood 5 days after the last immunization. The titer and specificity of the antiserum were evaluated, and the expression of rP450scc in normal rat brain and primary rat astrocytes was detected by using ELISA, Western blot and immunocytochemcal staining. RESULTS: The titer of the antiserum was 1:6,400. Western blot analysis showed that the rP450scc protein in rat brain, testis and adrenal gland homogenate was recognized by the antiserum as a single band at M(r) being 50,000, which indicated a high specificity of the antiserum. Hypothalamus, cerebral cortex, and hippocampus of rat brain and the cytoplasm of cultured rat astrocytes were positively stained by the antiserum. CONCLUSION: A highly specific anti-rP450scc antibody was prepared. The antibody can be used to study the expression and distribution of rP450scc in rat brain.


Assuntos
Anticorpos/análise , Anticorpos/imunologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Sequência de Aminoácidos , Animais , Anticorpos/química , Anticorpos/metabolismo , Especificidade de Anticorpos , Astrócitos/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Regulação da Expressão Gênica , Imuno-Histoquímica , Masculino , Dados de Sequência Molecular , Peptídeos/análise , Peptídeos/síntese química , Peptídeos/química , Coelhos , Ratos , Ratos Sprague-Dawley
12.
Eur J Endocrinol ; 150(1): 49-56, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14713279

RESUMO

OBJECTIVE: Immunoglobulin G (IgG) antibodies to the steroidogenic enzymes 21-hydroxylase (21OH) and side-chain cleavage enzyme (SCC) are important diagnostic markers for autoimmune Addison's disease and autoimmune polyendocrine syndromes (APS) types I and II. The characterization of autoantibody (IgG) subclasses may reveal information on how tIssue destruction takes place; therefore, IgG subtypes of anti-21OH and anti-SCC antibodies from sera of patients with Addison's disease, APS I and APS II were determined using recombinant 21OH and SCC. METHODS: SCC(51-521) and his-SCC(51-521) were expressed by pET-scc in the Escherichia coli strain BL21 Star (DE3) and inclusion bodies were purified. Full-length, human 21OH fused to an N-terminal 6x histidine affinity tag was expressed in insect cells by using the baculovirus expression system bac-to-bac. Western blots were used to investigate the IgG subtype(s) of the autoantibodies against 21OH and SCC in patients and healthy blood donors. RESULTS: All anti-SCC positive sera (n=10) contained autoantibodies of the IgG1 subclass, while four out of ten also contained IgG3. All anti-21OH positive sera (n=16) had autoantibodies exclusively against IgG1. Sera from 20 healthy subjects did not show any reactivity against 21OH or SCC. CONCLUSIONS: The finding of a predominating IgG1 response against 21OH and SCC may suggest that T helper (Th) cells of the Th1 subclass are involved in destruction of the adrenal cortex in patients with autoimmune Addison's disease.


Assuntos
Doença de Addison/imunologia , Autoanticorpos/imunologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Esteroide 21-Hidroxilase/imunologia , Especificidade de Anticorpos , Autoanticorpos/sangue , Biomarcadores , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Regulação Enzimológica da Expressão Gênica , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Esteroide 21-Hidroxilase/genética , Linfócitos T/imunologia
13.
Clin Endocrinol (Oxf) ; 59(5): 593-8, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14616882

RESUMO

OBJECTIVE: The prevalence of antibodies in different organ-specific autoimmune diseases can vary depending on the racial group studied. Data on the prevalence of antibodies against steroidogenic enzymes in Addison's disease is available only for white Caucasians. We have evaluated the frequency of antibodies against adrenal cytoplasm, 21-hydroxylase, 17-alpha-hydroxylase and side-chain cleavage enzyme in a cohort of Indian patients with Addison's disease of idiopathic and granulomatous aetiology. DESIGN: Study of all patients with Addison's disease on whom serum samples were available (84% of total), presenting to the Endocrinology Department in a teaching hospital in India, between 1990 and 1999. PATIENTS: Thirty-eight patients with Addison's disease (19 idiopathic, 19 granulomatous). METHODS: A radiobinding assay using in vitro transcribed and translated recombinant human 35S-labelled 21-hydroxylase, 17-alpha-hydroxylase and side-chain cleavage enzymes was utilized to detect the respective antibodies. Adrenal cytoplasmic antibodies were measured by indirect immunofluorescence on cryostatic sections of human adrenal cortex. RESULTS: Of the 19 patients with idiopathic Addison's disease, adrenal cytoplasmic antibodies were present in five (26%) patients, while 21-hydroxylase antibodies were present in four (21%) subjects. The frequency of 21-hydroxylase antibodies was similar among patients with isolated idiopathic Addison's disease (3/13, 23%), and those associated with other organ-specific autoimmune diseases (1/6, 17%). 17-alpha-hydroxylase and side-chain cleavage antibodies were present in four (21%) and three (16%) patients, respectively. Overall, at least one of the three antibodies was present in eight (42%) subjects. All four female patients with premature ovarian failure had antibodies against 17-alpha-hydroxylase and/or side-chain cleavage enzyme. Two (11%) patients with granulomatous Addison's disease had adrenal antibodies. Of these, one patient with enlarged and calcified adrenal gland secondary to tuberculosis had a high titre of antibodies against all three steroidogenic enzymes. CONCLUSIONS: Antibodies to 21-hydroxylase enzyme are less frequent in idiopathic Addison's disease in north Indians, when compared with other Caucasians. In contrast, the prevalence of 17-alpha-hydroxylase and side-chain cleavage enzyme antibodies is similar to those reported. High titre antibodies against steroidogenic enzymes may occasionally be present in patients with clinical evidence of tuberculous Addison's disease.


Assuntos
Doença de Addison/imunologia , Glândulas Suprarrenais/imunologia , Autoanticorpos/sangue , Doença de Addison/etiologia , Adolescente , Adulto , Doenças Autoimunes/complicações , Doenças Autoimunes/imunologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Citoplasma/imunologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Índia/etnologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estatísticas não Paramétricas , Esteroide 17-alfa-Hidroxilase/imunologia , Esteroide 21-Hidroxilase/imunologia , Tuberculose/complicações , Tuberculose/imunologia , População Branca
14.
Eur J Endocrinol ; 148(5): 565-70, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12720541

RESUMO

DESIGN: Adrenal cortex autoantibodies (ACA), steroid-producing cell autoantibodies (StCA) and autoantibodies (Abs) to steroidogenic enzymes in three groups of patients with premature ovarian failure (POF), 15 with autoimmune Addison's disease (AD), 26 with non-adrenal autoimmune diseases and 31 with isolated POF, have been assessed. METHODS: ACA and StCA were measured using an immunofluorescence technique. Abs to 21-hydroxylase (21-OH), to 17alpha-hydroxylase (17alpha-OH) and to cytochrome P450 side-chain cleavage (P450scc) were measured using an immunoprecipitation assay. RESULTS: Seventy-three percent of patients with POF and AD were positive for StCA, 93% for 17alpha-OH and/or P450scc Abs, 93% for ACA and 100% for 21-OH Abs. Among patients with POF and non-adrenal autoimmune diseases, 8% were positive for StCA, 12% for 17alpha-OH and/or P450scc Abs, and 8% and 12% for ACA and 21-OH Abs respectively. StCA, 17alpha-OH and/or P450scc Abs were all found in 10% of patients with isolated POF, and 13% had ACA and 21-OH Abs. All StCA-, 17alpha-OH- and/or P450scc Abs-positive patients were also positive for ACA and 21-OH Abs. Two patients with isolated POF who were ACA and 21-OH Ab positive developed AD 3 and 5 Years after the onset of POF. CONCLUSION: This study has shown that, when POF is associated with AD, StCA, 17alpha-OH and/or P450scc Abs are present in the majority of patients, while in the other two groups these Abs are detectable in a much lower proportion of patients. Measurement of ACA/21-OH Abs in some patients with POF may be important in identifying patients at risk of developing overt AD.


Assuntos
Doença de Addison/imunologia , Autoanticorpos/análise , Enzimas/imunologia , Enzimas/metabolismo , Insuficiência Ovariana Primária/imunologia , Esteroides/biossíntese , Doença de Addison/complicações , Córtex Suprarrenal/imunologia , Adulto , Doenças Autoimunes/imunologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Feminino , Humanos , Insuficiência Ovariana Primária/complicações , Esteroide 17-alfa-Hidroxilase/imunologia
15.
Fertil Steril ; 78(2): 270-9, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12137862

RESUMO

OBJECTIVE: To determine the prevalence of steroid-cell autoantibodies, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) antibodies, 17alpha-hydroxylase (17alpha-OH) antibodies, and P450 side-chain cleavage antibodies in premature ovarian failure. DESIGN: Cross-sectional, observational study. SETTING: Academic research hospitals. PATIENT(S): Eighty-one women with premature ovarian failure, 20 women with Addison disease not associated with premature ovarian failure, 42 women with type 1 diabetes mellitus, and 90 healthy women. MAIN OUTCOME MEASURE(S): Serum levels of steroid-cell autoantibodies, 17alpha-OH antibodies, P450 side-chain cleavage antibodies, and 3beta-HSD antibodies. RESULT(S): Steroid-cell autoantibodies were present in none of 57 women with isolated premature ovarian failure or premature ovarian failure plus nonadrenal autoimmune disease and in 21 of 24 (87%) women with Addison disease-related premature ovarian failure. 17alpha-Hydroxylase antibodies and P450 side-chain cleavage antibodies were significantly more frequent in women positive for adrenal autoantibodies than in those negative for adrenal autoantibodies (50% vs. 0% and 71% vs. 2%, respectively). The presence of 17alpha-OH antibodies or P450 side-chain cleavage antibodies was strongly associated with presence of steroid-cell autoantibodies. Two of 24 (8%) women with Addison disease-related premature ovarian failure and 1 of 57 (2%) women with isolated premature ovarian failure or premature ovarian failure plus nonadrenal autoimmune disease were positive for 3beta-HSD antibodies. None of 20 adult women with autoimmune Addison disease and none of 42 adult women with type 1 diabetes mellitus not associated with premature ovarian failure was positive for 3beta-HSD antibodies. CONCLUSION(S): Markers of steroid-cell autoimmunity are found only rarely in idiopathic premature ovarian failure not associated with Addison disease. Most women with Addison disease-related premature ovarian failure were positive for steroid-cell autoantibodies, 17alpha-OH antibodies, or P450 side-chain cleavage antibodies. 3beta-Hydroxysteroid dehydrogenase antibodies do not appear to be a major marker of steroid-cell autoimmunity.


Assuntos
3-Hidroxiesteroide Desidrogenases/imunologia , Autoimunidade , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Insuficiência Ovariana Primária/imunologia , Esteroide 17-alfa-Hidroxilase/imunologia , Doença de Addison/imunologia , Adolescente , Adulto , Doenças Autoimunes/imunologia , Autoimunidade/fisiologia , Estudos Transversais , Diabetes Mellitus/imunologia , Feminino , Humanos
16.
Microbiol Immunol ; 46(5): 343-51, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12139394

RESUMO

In the present study, the anti-tumor mechanism of Z-100 was investigated with the use of pulmonary metastasis of B16F10 melanoma. In B16F10 mice, Th1 cytokine production (IL-2, IFN-gamma) was suppressed in comparison with normal mice. On the other hand, Th2 cytokine production (IL-4, IL-10) was increased in the B16F10 mice. The administration of Z-100 to B16F10 mice restored the balance of Th1/Th2 cell responses from the Th2 dominant state to the normal state. Z-100 significantly suppressed the pulmonary metastasis of B16F10 melanoma in a dose-dependent manner. These results suggest that Z-100 restored the breakdown of Th1 cell responses, resulting in the suppression of pulmonary metastasis of B16F10 melanoma. Moreover, Z-100 decreased the corticosterone levels, which is known to suppress the Th1 cell responses, in both serum specimens and splenic tissue, and the steroidogenic CYP11A1 mRNA expression in CD4+ T cells. These results suggest that a suppression of pulmonary metastasis and restoration of Thl/Th2 cell responses by Z-100 may be due to the decrease in the corticosterone levels and the steroidogenic CYP11A1 mRNA expression of CD4+ T cells in B16F10 mice. Further, the role of Th1 cytokine, IFN-gamma, on these activities of Z-100 was examined. The suppressive effects of Z-100 on pulmonary metastasis and restoration of Th1/Th2 cell responses were eliminated by the administration of anti-IFN-gamma mAb. Moreover, the suppressive effects of Z-100 on glucocorticoid-genesis were eliminated by the administration of anti-IFN-gamma-mAb. These results suggest that Z-100 restores the balance of Th1/Th2 cell responses via the suppression of glucocorticoid-genesis by Z-100-induced IFN-gamma. IFN-gamma acts as a key cytokine in anti-tumor activities of Z-100.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antineoplásicos/imunologia , Glucocorticoides/antagonistas & inibidores , Lipídeos/imunologia , Neoplasias Pulmonares/terapia , Mananas/imunologia , Melanoma Experimental/terapia , Células Th1/imunologia , Células Th2/imunologia , Animais , Antineoplásicos/farmacologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/biossíntese , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Corticosterona/sangue , Ensaio de Imunoadsorção Enzimática , Glucocorticoides/biossíntese , Interferon gama/imunologia , Interferon gama/metabolismo , Lipídeos/farmacologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/secundário , Masculino , Mananas/farmacologia , Melanoma Experimental/imunologia , Melanoma Experimental/secundário , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Th1/metabolismo , Células Th2/metabolismo
17.
Eur J Endocrinol ; 146(1): 113-9, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11751076

RESUMO

OBJECTIVE: Autoimmune polyglandular syndrome type 1 (APS-1) is a disease associated with defects of the autoimmune regulator gene and is characterized by autoimmune lesions of several tissues, predominantly endocrine glands, with multiple autoantibodies. In this study we describe autoantigenic epitopes on cholesterol side-chain cleavage enzyme (P450scc) using sera from Finnish and Sardinian patients with APS-1, and analyze the epitope reactivities during disease follow-up. METHODS: A series of P450scc cDNA fragments were expressed in E. coli and tested by immunoblotting assay using the patients' sera. RESULTS: Epitope regions were found over the whole P450scc molecule except the last N- (amino acids (aa) 1-40) and C-termini (aa 456-521). The strongest reactivity with patients' sera was found with central and C-terminal regions of the P450scc protein. All studied patients had IgG1 subclass antibodies. CONCLUSIONS: The results show that Finnish and Sardinian patients with APS-1 have similar, polyclonal immune reactions against P450scc, and that epitope reactivities did not change during the disease course. These results support the opinion that autoantibodies against P450scc and their epitope reactivity pattern are formed at an early stage of steroidogenic autoimmunity.


Assuntos
Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Colesterol/metabolismo , Mapeamento de Epitopos , Poliendocrinopatias Autoimunes/imunologia , Adolescente , Adulto , Autoanticorpos/análise , Criança , Enzima de Clivagem da Cadeia Lateral do Colesterol/sangue , Feminino , Finlândia , Deleção de Genes , Humanos , Immunoblotting , Imunoglobulina G/química , Imunoglobulina G/classificação , Itália , Masculino , Poliendocrinopatias Autoimunes/sangue , Poliendocrinopatias Autoimunes/enzimologia
18.
Ann Endocrinol (Paris) ; 62(2): 193-201, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11353894

RESUMO

Sera from 300 Italian patients with Addison's disease were collected over a 30 year period. Among these patients, 82% had autoimmune disease, 13% had tuberculosis and 5% had another causal condition. In 59% of the cases, autoimmune disease was associated with the autoimmune manifestations contributing to the description of polyglandular autoimmune disease (PGAD). In PGAD type 1, the disease was associated with chronic candidiasis and/or chronic hypoparathyroidism. In PGAD type 2, the patients had autoimmune thyroid disease and/or diabetes mellitus type 1, and in PGAD type 4, they presented a combination with other autoimmune diseases excluding those previously mentioned. Finally, the autoimmune disease was apparently isolated in 41% of the cases. In addition, patients with these four forms of disease exhibited a different genetic pattern, sex distribution, and age at presentation in addition to minor frequency of autoimmune diseases. Adrenal cortex autoantibodies directed against 21-hydroxylase were common serological markers for these four main clinical forms, showing a very high frequency at clinical onset of adrenal insufficiency. In some patients, steroid-producing cell autoantibodies were also present and correlated with gonadal failure and they recognize of 17alpha-hydroxylase or P450 side chain cleavage enzymes as target antigens.


Assuntos
Doença de Addison/imunologia , Autoimunidade , Poliendocrinopatias Autoimunes/imunologia , Doença de Addison/epidemiologia , Doença de Addison/genética , Doença de Addison/patologia , Córtex Suprarrenal/imunologia , Autoanticorpos/sangue , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Humanos , Glândulas Paratireoides/imunologia , Poliendocrinopatias Autoimunes/epidemiologia , Poliendocrinopatias Autoimunes/genética , Poliendocrinopatias Autoimunes/patologia , Esteroide 17-alfa-Hidroxilase/imunologia , Esteroide 21-Hidroxilase/imunologia
19.
Clin Endocrinol (Oxf) ; 54(2): 211-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11207636

RESUMO

OBJECTIVE: The aim of the present study was to investigate Norwegian patients with autoimmune polyendocrine syndrome type I (APS I), with respect to occurrence and clinical presentation, reactivity towards different autoantigenes and mutations in the autoimmune regulator (AIRE) gene. PATIENTS: Twenty Norwegian patients from 15 families with APS I (11 males, nine females; mean age 26 years, range 4--54) were included by contacting all major hospitals in Norway. METHODS: Clinical data was collected from both patients and their physicians by the use of questionnaires and patient records. Autoantibodies were analysed using radioimmunoassays based on antigen synthesized by in vitro transcription and translation. AIRE mutations were determined by DNA sequence analysis. RESULTS: The prevalence of APS I in Norway was estimated to be about 1 : 80,000 individuals. We found about the same distribution of disease characteristics as has been reported in Finnish patients. The diagnosis was delayed in many individuals. In two thirds of the cases, the patients were admitted in Hospital with acute adrenal insufficiency or hypocalcaemic crisis. Forty percent of these patients already had one of the main disease manifestations. Four different mutations in the AIRE gene were found in the Norwegian cohort. A 13-bp deletion in exon 8 (1085--1097(del)) was the most frequent mutation, present in 22/40 (55%) of the alleles. Eighty-five percent of the patients had either autoantibodies against 21 hydroxylase or aromatic L-amino acid decarboxylase. Five of eight women (age > 13 years) had ovarian failure, and all of these had antibodies against side-chain cleavage enzyme (P = 0.0002). CONCLUSION: Norwegian patients with APS I clinically resemble patients from Finland and other European countries. The diagnosis APS I must be considered in children and adolescents with chronic mucocutaneous candidiasis, autoimmune adrenocortical failure or hypoparathyroidism in order to avoid fatal complications. Analysis of autoantibodies and mutational analysis of the AIRE gene are valuable diagnostic tools, especially in the early stages of the disease.


Assuntos
Poliendocrinopatias Autoimunes/epidemiologia , Adolescente , Adulto , Descarboxilases de Aminoácido-L-Aromático/imunologia , Autoanticorpos/sangue , Criança , Pré-Escolar , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Poliendocrinopatias Autoimunes/genética , Poliendocrinopatias Autoimunes/imunologia , Prevalência , Insuficiência Ovariana Primária/imunologia , Análise de Sequência de DNA , Esteroide 21-Hidroxilase/imunologia , Fatores de Transcrição/genética , Proteína AIRE
20.
Biol Reprod ; 63(1): 165-71, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10859256

RESUMO

Leydig cells of the adult rat testis differentiate postnatally from spindle-shaped cells in the testis interstitium during the neonatal-prepubertal period. Which spindle-shaped cell types are the precursor for Leydig cells and the stimulus for initiation of their differentiation are, however, two unresolved issues. In the present study, our objectives were to identify unequivocally which spindle-shaped cells are the precursors to Leydig cells and to test whether the initiation of their differentiation into Leydig cells depends on LH. Testes from fifteen groups of Sprague-Dawley rats (n = 4 per group) from 7-21 days of age were fixed in Bouin solution and embedded in paraffin. Immunoexpression of 3beta-hydroxysteroid dehydrogenase (3betaHSD), cytochrome P450 side-chain cleavage (P450(scc)), 17alpha-hydroxylase cytochrome P450 (P450(c17)), and LH receptors (LHR) in interstitial cells (other than fetal Leydig cells) was observed using the avidin biotin method. Of all spindle-shaped cell types in the testis interstitium, only the peritubular mesenchymal cells showed positive immunolabeling for all three steroidogenic enzymes, beginning from the 11th postnatal day. All three enzymes were expressed simultaneously in these cells, and their numbers increased significantly thereafter. Immunoexpression of LHR in a few of these cells was just evident for the first time on postnatal Day 12 (i.e., after acquiring the steroidogenic enzyme activity). Their numbers gradually increased with time. The number of immunolabeled cells per 1000 interstitial cells (excluding fetal Leydig cells and capillary endothelial cells) was not significantly different for the three steroidogenic enzymes tested at all ages; however, a lower value was observed for LHR at each time-point. Based on these observations, we suggest that 1) the precursor cell type for the adult generation of Leydig cells in the postnatal rat testis is the peritubular mesenchymal cells, 2) precursor cells acquire 3beta-HSD, P450(scc), and P450(c17) enzyme activity simultaneously during Leydig cell differentiation, and 3) onset of precursor cell differentiation during Leydig cell development does not depend on LH.


Assuntos
Diferenciação Celular/fisiologia , Células Intersticiais do Testículo/citologia , Maturidade Sexual/fisiologia , 3-Hidroxiesteroide Desidrogenases/imunologia , 3-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Animais Recém-Nascidos , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Feminino , Células Intersticiais do Testículo/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley , Receptores do LH/imunologia , Receptores do LH/metabolismo , Esteroide 17-alfa-Hidroxilase/imunologia , Esteroide 17-alfa-Hidroxilase/metabolismo
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