RESUMO
A benign virilizing adrenal adenoma is rare among adrenal neoplasms in middle-aged women. A 39-yr-old Japanese woman who presented with hirsutism, obesity, diabetes mellitus and hypertension was admitted. Plasma concentrations of testosterone and DHEAS were high. While the basal level of plasma ACTH was suppressed, serum cortisol level was high and its circadian rhythm was absent. Serum cortisol level was not suppressed with the low- and high-dose overnight dexamethasone suppression test. Abdominal computed tomography showed a left adrenal tumor, and an adrenocortical scintigraphy revealed uptake of the tracer on the left side. Polycystic ovaries were also found and bone mineral density revealed osteoporosis. Histopathological features of resected adrenal tumor were consistent with those of adrenocortical adenoma. Immunoreactivity of all the steroidogenic enzymes was apparent in the tumor cells and particularly dehydroepiandrosterone sulfotransferase (DHEA-ST) immunoreactivity was markedly expressed. Cortical atrophy and reduced expression of DHEA-ST were detected in the cortex of the adjacent non-neoplastic adrenal gland. Plasma testosterone, DHEAS and cortisol levels returned to normal after surgery, concomitantly with the disappearance of polycystic ovaries. This is a very rare case of virilizing adrenocortical adenoma complicated with Cushing's syndrome (CS).
Assuntos
Neoplasias do Córtex Suprarrenal/complicações , Adrenalectomia , Adenoma Adrenocortical/complicações , Síndrome de Cushing/complicações , Resistência à Insulina , Síndrome do Ovário Policístico/terapia , Virilismo/terapia , Neoplasias do Córtex Suprarrenal/diagnóstico , Neoplasias do Córtex Suprarrenal/patologia , Neoplasias do Córtex Suprarrenal/cirurgia , Adenoma Adrenocortical/diagnóstico , Adenoma Adrenocortical/patologia , Adenoma Adrenocortical/cirurgia , Adulto , Feminino , Humanos , Síndrome do Ovário Policístico/etiologia , Radiografia Abdominal , Virilismo/etiologiaRESUMO
It has been reported that agonists of peroxisome proliferator-activated receptor gamma (PPARgamma) inhibit proliferation of breast carcinoma cells, but the biological significance of PPARgamma remains undetermined in human breast carcinomas. Therefore, we immunolocalized PPARgamma in 238 human breast carcinoma tissues. PPARgamma immunoreactivity was detected in 42% of carcinomas, and was significantly associated with the status of estrogen receptor (ER) alpha, ERbeta, progesterone receptor, retinoic X receptors, p21 or p27, and negatively correlated with histological grade or cyclooxygenase-2 status. PPARgamma immunoreactivity was significantly associated with an improved clinical outcome of breast carcinoma patients by univariate analysis, and multivariate analysis demonstrated that PPARgamma immunoreactivity was an independent prognostic factor for overall survival in ERalpha-positive patients. We then examined possible mechanisms of modulation by PPARgamma on estrogenic actions in MCF-7 breast carcinoma cells. A PPARgamma activator, 15-deoxy-Delta(12,14)- prostaglandin J(2) (15d-PGJ(2)), significantly inhibited estrogen-responsive element-dependent transactivation by estradiol in MCF-7 cells, which was blocked by addition of a PPARgamma antagonist GW9662. Subsequent study, employing a custom-made microarray focused on estrogen-responsive genes, revealed that mRNA expression was significantly regulated by estradiol in 49 genes, but this significance vanished on addition of 15d-PGJ(2) in 16 out of 49 (33%) genes. These findings were confirmed by real-time PCR in 11 genes. 15d-PGJ(2) significantly inhibited estrogen-mediated proliferation of MCF-7 cells, and caused accumulation of p21 and p27 protein. These results suggest that PPARgamma is mainly expressed in well-differentiated and ER-positive breast carcinomas, and modulates estrogenic actions.
Assuntos
Neoplasias da Mama/metabolismo , Estrogênios/farmacologia , Regulação Neoplásica da Expressão Gênica , PPAR gama/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/metabolismo , Proliferação de Células , Quimioterapia Adjuvante , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Feminino , Humanos , Fatores Imunológicos/farmacologia , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Análise de Sequência com Séries de Oligonucleotídeos , PPAR gama/genética , Prostaglandina D2/análogos & derivados , Prostaglandina D2/farmacologia , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ativação Transcricional , Células Tumorais CultivadasRESUMO
Regional distribution of prolactin-releasing peptide (PrRP) in the human brain was studied by radioimmunoassay. The antiserum raised against human PrRP-31 in a rabbit was used in the assay, which showed 100% cross reaction with PrRP-20 and no significant cross reaction with other peptides. The highest concentrations of immunoreactive-PrRP were found in hypothalamus (912 +/- 519 fmol/g wet weight, n = 6, mean +/- SEM), followed by medulla oblongata (496 +/- 136 fmol/g wet weight) and thalamus (307 +/- 117 fmol/g wet weight). On the other hand, immunoreactive-PrRP was not detected in frontal lobe or temporal lobe (<50 fmol/g wet weight). Sephadex G50 column chromatography of the immunoreactive-PrRP in the hypothalamus and medulla oblongata showed three immunoreactive peaks; one peak eluting in the position of PrRP-20, one eluting in the position of PrRP-31 and one eluting earlier. Reverse phase high-performance liquid chromatography (HPLC) of these brain tissue extracts showed a peak eluting in the position of PrRP-20 and PrRP-31. The present study has shown for the first time the presence of immunoreactive-PrRP in the human brain. The immunoreactive-PrRP levels in the human hypothalamus were, however, lower than the levels of other neuropeptides with prolactin-releasing activity, such as thyrotropin-releasing hormone and vasoactive intestinal polypeptide.
Assuntos
Química Encefálica , Hormônios Hipotalâmicos/análise , Hormônios Hipotalâmicos/imunologia , Neuropeptídeos/análise , Neuropeptídeos/imunologia , Adulto , Idoso , Cromatografia Líquida de Alta Pressão , Reações Cruzadas/imunologia , Feminino , Humanos , Hipotálamo/química , Hipotálamo/imunologia , Soros Imunes/imunologia , Radioisótopos do Iodo , Masculino , Bulbo/química , Bulbo/imunologia , Pessoa de Meia-Idade , Especificidade de Órgãos , Hormônio Liberador de Prolactina , Radioimunoensaio , Tálamo/química , Tálamo/imunologiaRESUMO
OBJECTIVE AND STUDY DESIGN: Urocortin is a recently identified neuropeptide of the corticotrophin-releasing factor (CRF) family in the mammalian brain and has been demonstrated to stimulate ACTH secretion from pituitary cells, but its expression in human brain tissue including the hypothalamus has not been examined. In this study, we first examined urocortin expression in the hypothalamus (20 cases) and pituitary stalks (17 cases) of human brain obtained from autopsy using immunohistochemistry and mRNA in situ hybridization. RESULTS: Neither urocortin immunoreactivity nor mRNA hybridization signals were detected in the hypothalami and pituitary stalks while CRF immunoreactivity was detected in the paraventricular nuclei of the hypothalami in 10/20 cases and in nerve fibres of the stalks in 17/17 cases. These results indicate that urocortin does not act on the hypothalamo-pituitary-adrenal axis, at least not in the same manner as CRF in humans. We then examined urocortin expression in various portions of the brain in 7 cases. Both urocortin immunoreactivity and mRNA hybridization were detected in Purkinje cells of the cerebellum and anterior horn cells of the spinal cord in specimens examined. Urocortin expression was, however, variably seen in superior olivary nuclei (two out of six cases examined) and in the Edingar-Westphal nuclei (one out of three cases examined). CONCLUSIONS: The distribution of urocortin in the human central nervous system suggests that urocortin may work as a neurotransmitter like other neuropeptides in the human.
Assuntos
Química Encefálica , Hormônio Liberador da Corticotropina/análise , Adolescente , Adulto , Idoso , Animais , Células do Corno Anterior/química , Criança , Pré-Escolar , Hormônio Liberador da Corticotropina/genética , Feminino , Humanos , Hipotálamo/química , Imuno-Histoquímica , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , Núcleo Olivar/química , Hipófise/química , Células de Purkinje/química , RNA Mensageiro/análise , Ratos , UrocortinasRESUMO
We report here the identification, characterization, and expression of a novel rat acyl-CoA synthetase (ACS) designated as ACS5. ACS5 consists of 683 amino acids and is approximately 60% identical to the previously characterized ACS1 and ACS2. ACS5 was overproduced in Escherichia coli cells and then purified to near homogeneity. The purified enzyme utilized a wide range of saturated fatty acids similar to those utilized by ACS1 and ACS2, but differed in its preference for C16-C18 unsaturated fatty acids. Northern blot analysis revealed that ACS5 mRNA is present most abundantly in the small intestine, and to a much lesser extent in the lung, liver, adrenal gland, adipose tissue, and kidney. In situ hybridization of rat ileum revealed abundant accumulation of ACS5 transcripts in foveolar epithelial cells. The hepatic level of ACS5 mRNA was significantly increased by refeeding a fat-free high sucrose diet and reduced by fasting or refeeding a high cholesterol diet, whereas that in the small intestine was not significantly altered by various dietary conditions. In contrast to the absence of ACS1 mRNA in undifferentiated 3T3-L1 preadipocytes, ACS5 mRNA was present in proliferating 3T3-L1 preadipocytes and its level remained unaltered during differentiation, suggesting that ACS5 may provide the acyl-CoA utilized for the synthesis of cellular lipids in proliferating preadipocytes.
Assuntos
Adipócitos/enzimologia , Coenzima A Ligases/metabolismo , Intestinos/enzimologia , Adipócitos/citologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Divisão Celular , Coenzima A Ligases/genética , DNA Complementar , Gorduras na Dieta/administração & dosagem , Células Epiteliais/enzimologia , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica , Hibridização In Situ , Intestinos/citologia , Proteínas Mitocondriais , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RatosRESUMO
OBJECTIVE: Oestrogen produced locally by aromatase is thought to participate in numerous biological functions in the adult central nervous system (CNS). However, little is known about aromatase expression in the human CNS. DESIGN: We examined aromatase expression in human brain regions, (4 men, 2 women) obtained from autopsy, by reverse transcriptase (RT)-polymerase chain reaction (PCR) and also studied alternative use of multiple exons 1 of its gene, which is involved in tissue specific expression of aromatase in human. RESULTS: The amount of aromatase mRNA determine by RT-PCR assay in 6 cases tended to be highest in pons, thalamus, hypothalamus and hippocampus. Analysis of multiple exons 1 revealed that 1f, considered specific for brain, as well as 1b (fibrolast type) and 1d (gonadal type), were expressed. 1d and 1f tended to be utilized in hypothalamus, thalamus and amygdala. The amount of overall mRNA expression was also higher in hypothalamus, thalamus and amygdala than in other regions of the brain. There were no differences of utilization of exons 1 and mRNA expression of aromatase between female and male brain. CONCLUSIONS: These results demonstrate that aromatase is expressed widely in various regions of human brain tissues in both men and women.
Assuntos
Aromatase/análise , Encéfalo/enzimologia , Adulto , Idoso , Processamento Alternativo , Aromatase/genética , Cerebelo/enzimologia , Éxons , Feminino , Humanos , Hipotálamo/enzimologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Ponte/enzimologia , RNA Mensageiro/análise , Lobo Temporal/enzimologia , Tálamo/enzimologiaRESUMO
We report herein the cDNA cloning of a novel rat acyl-CoA synthetase (ACS) that preferentially uses arachidonate and eicosapentaenoate. This newly identified ACS (designated ACS4) contains 670 amino acids and is 68% identical to rat ACS3, a previously characterized ACS that is highly expressed in brain. ACS4 was overproduced in Escherichia coli and the resulting enzyme was purified to homogeneity. The purified enzyme utilizes arachidonate and eicosapentaenoate most preferentially among C8-C22 saturated fatty acids and C14-C22 unsaturated fatty acids. Kinetic analyses revealed that the enzyme has a high affinity for arachidonate and eicosapentaenoate and low affinity for palmitate. ACS4 transcripts are detectable in a wide range of tissues, with the highest level in adrenal gland. Immunoreactivity to ACS4 was detected in the zona fasciculata and reticularis of adrenal gland, in the corpus luteum and stromal luteinized cells in ovary, and in the Leydig cells of testis.
Assuntos
Glândulas Suprarrenais/enzimologia , Ácido Araquidônico/metabolismo , Coenzima A Ligases/metabolismo , Ovário/enzimologia , Proteínas Repressoras , Proteínas de Saccharomyces cerevisiae , Testículo/enzimologia , Sequência de Aminoácidos , Animais , Northern Blotting , Coenzima A Ligases/química , DNA Complementar , Feminino , Masculino , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Proteínas Recombinantes/metabolismo , Homologia de Sequência de AminoácidosRESUMO
Adrenomedullin is a potent vasodilator peptide that was isolated from pheochromocytoma. Localization of adrenomedullin-like immunoreactivity was studied by immunocytochemistry in the human hypothalamus and adrenal gland. Adrenomedullin-immunoreactive cell bodies were found in the paraventricular, supraoptic and infundibular nuclei of the hypothalamus. Both magnocellular and parvocellular cells of the paraventricular nucleus were positively immunostained. Adrenomedullin-like immunoreactivity was localized in the adrenal medulla. No positive immunostaining was observed in the vascular endothelium, vascular smooth muscle cell or adrenal cortex. The preabsorption of the antiserum with synthetic human adrenomedullin (1-52) abolished the immunostaining. These findings indicate that adrenomedullin-like immunoreactivity is localized in the paraventricular, supraoptic and infundibular nuclei as well as in the adrenal medulla, and suggest that adrenomedullin acts as a neurotransmitter, a neuromodulator or a neurohormone in the human hypothalamus.
Assuntos
Glândulas Suprarrenais/metabolismo , Hipotálamo/metabolismo , Peptídeos/metabolismo , Vasodilatadores/metabolismo , Adrenomedulina , Idoso , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Núcleo Supraóptico/metabolismoRESUMO
Melanin-concentrating hormone (MCH) is a neuropeptide originally isolated from chum salmon pituitaries. To explore physiological roles of MCH in mammals, we studied the regional distribution of immunoreactive MCH in the rat tissues and the presence of immunoreactive MCH in human adrenal glands, adrenal tumors and plasma by radioimmunoassay, and the expression of MCH mRNA in rat tissues and human brain tissues by Northern blot analysis. Immunoreactive MCH was present in every region of rat brain and neurointermediate lobe of the pituitary gland, with the highest concentrations found in the hypothalamus (48.3 +/- 6.6 pmol/g wet weight, mean +/- SEM, n = 6). The immunoreactive MCH in rat hypothalamus, frontal lobe, and pons and medulla oblongata was eluted in the position of synthetic human/rat MCH in reverse-phase high-performance liquid chromatography. No immunoreactive MCH was detected in the rat peripheral tissues. Northern blot analysis showed that a single species of MCH mRNA (approximately 1 kb) was expressed specifically in the rat and human hypothalamus, but not detectable in other regions of brain or rat peripheral tissues. Immunoreactive MCH was not detected in human adrenal glands (< 0.5 pmol/g wet weight, n = 9) or adrenal tumors including pheochromocytomas. Immunoreactive MCH were not detected in plasma obtained from human healthy subjects (< 0.25 pmol/l) and rat (< 0.25 pmol/l).(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Hormônios Hipotalâmicos/análise , Melaninas/análise , Hormônios Hipofisários/análise , Adulto , Animais , Northern Blotting , Química Encefálica , Cromatografia Líquida de Alta Pressão , Feminino , Lobo Frontal/química , Humanos , Hormônios Hipotalâmicos/genética , Hipotálamo/química , Masculino , Bulbo/química , Melaninas/genética , Especificidade de Órgãos , Hipófise/química , Hormônios Hipofisários/genética , Ponte/química , RNA Mensageiro/análise , Radioimunoensaio , Ratos , Ratos Sprague-DawleyRESUMO
In an effort to characterize mRNAs that are highly expressed during atherosclerosis, we employed differential hybridization screening of a cDNA library constructed from total RNA derived from the aorta of Watanabe heritable hyperlipidemic (WHHL) rabbits. Characterizing the cDNAs for mRNAs that are present in large amounts in WHHL rabbit aortae, we identified a positive clone encoding matrix gamma-carboxyglutamic acid protein (MGP). The primary structure of rabbit MGP was deduced from nucleotide sequence analysis of the cDNA. Northern blot analysis of total RNA prepared from aortae of WHHL and normal rabbits of various ages indicated that the expression of MGP mRNA increased in proportion to the progression of atherosclerosis in WHHL rabbits. Analysis of MGP mRNA by in situ hybridization revealed that a significant amount of MGP mRNA is accumulated in atherosclerotic lesions of WHHL rabbits, suggesting that the expression of MGP mRNA is correlated with the progression of atherosclerosis.
Assuntos
Aorta/metabolismo , Arteriosclerose/metabolismo , Proteínas de Ligação ao Cálcio/biossíntese , Proteínas da Matriz Extracelular , Hiperlipoproteinemia Tipo II/metabolismo , Sequência de Aminoácidos , Animais , Arteriosclerose/genética , Arteriosclerose/fisiopatologia , Sequência de Bases , Northern Blotting , Proteínas de Ligação ao Cálcio/análise , Proteínas de Ligação ao Cálcio/fisiologia , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Progressão da Doença , Expressão Gênica , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/fisiopatologia , Hibridização In Situ , Masculino , Dados de Sequência Molecular , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Coelhos , Homologia de Sequência de Aminoácidos , Proteína de Matriz GlaRESUMO
Pituitary adenylate cyclase activating polypeptide (PACAP) is a novel hypothalamic peptide consisting of 38 amino acids (PACAP1-38) with a potent stimulatory action on adenylate-cyclase in rat pituitary. The presence of PACAP-like immunoreactivity in human brain was studied by radioimmunoassay. Co-localization of PACAP with arginine vasopressin and oxytocin was investigated by immunocytochemistry in the human hypothalamus. Immunoreactive PACAP was detected in all regions of human brain (cortex, thalamus, hypothalamus, pons and hemisphere of cerebellum) with the highest levels found in the hypothalamus (8.5 +/- 1.9 pmol/g wet weight, n = 4, mean +/- S.E.M.). High performance liquid chromatography of the human hypothalamic extract showed that approximately 50% of the immunoreactive PACAP was eluted in the position of PACAP1-38. Immunocytochemical studies showed the presence of PACAP immunoreactive neurons in the paraventricular and supraoptic nuclei of human hypothalamus. PACAP co-localized with arginine vasopressin in magnocellular cells of these nuclei. These findings suggest that PACAP1-38 plays important physiological roles in the human hypothalamus.
Assuntos
Arginina Vasopressina/análise , Química Encefálica , Encéfalo/citologia , Hipotálamo/química , Hipotálamo/citologia , Neuropeptídeos/análise , Neurotransmissores/análise , Idoso , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , RadioimunoensaioRESUMO
The patient was a 26-year-old man with Cushing's disease who underwent transsphenoidal microscopic surgery for a pituitary microadenoma. His postoperative course was uneventful, but he died suddenly five years after the operation. At autopsy, a ruptured dissecting aneurysm with marked atherosclerosis was observed in the aorta. In the pituitary, a small focus of adrenocorticotropic hormone (ACTH) producing adenoma, possibly residual adenoma, was detected and Crooke's degeneration was observed in the non-tumorous pituitary gland. But immunohistochemical patterns of pituitary hormones in the non-tumorous pituitary gland were normal and the adrenal cortex was unremarkable. In the hypothalamus, corticotropin-releasing hormone immunoreactivity was not detected and arginine vasopressin was sporadically positive. Considering these findings, this patient may have developed subclinical hypercortisolism due to the residual adenoma at the time of autopsy, despite clinical remission. Cushing's syndrome is considered to be a risk factor dissecting aneurysm, and in this case the metabolic changes in Cushing's disease may have influenced the development of the dissecting aneurysm. Periodic cardiovascular re-evaluations should therefore be performed when there is clinical remission of Cushing's syndrome.