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1.
Int J Obes (Lond) ; 39(11): 1619-29, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26063331

RESUMO

BACKGROUND/OBJECTIVE: White-to-brown adipose tissue remodeling (browning) in response to different stimuli constitutes an active research area for obesity treatment. The emergence in traditional white adipose tissue (WAT) depots of multilocular adipocytes that express uncoupling protein 1 (UCP1) and resemble brown adipocytes, the so called 'brite' adipocytes, could contribute to increased energy expenditure. In rodents, obesogenic stimuli such as the intake of hyperlipidic diets can increase brown adipose tissue (BAT) thermogenic capacity and contribute to maintaining body weight. The aim of this study was to investigate the potential of two different hyperlipidic diets, a commercial high-fat (HF) diet and a highly palatable cafeteria (CAF) diet, to induce WAT browning. METHODS: We analyzed gene expression of a wide number of brown/brite adipocyte markers in different WAT depots, in BAT and in peripheral blood mononuclear cells (PBMCs) increasingly being used in nutrition studies as a potential source of biomarkers of physiological effects. We also performed morphological analysis of adipose tissue. RESULTS: Both HF diets studied were able to increase the expression of the markers studied in WAT in a depot-specific manner, as well as in BAT; some of these changes were also reflected in PBMCs. This increased browning capacity was translated into the appearance of UCP1- and CIDE-A (cell death-inducing DFFA-like effector A)-positive brite adipocytes in retroperitoneal WAT. Administration of the CAF diet, associated with higher adiposity, produced the strongest impact on the parameters studied while its withdrawal restored basal conditions. CONCLUSIONS: Acquisition of brown adipocyte features in WAT could evidence an adaptation to try to counteract increased adiposity due to the intake of HF diets. Additionally, PBMCs could constitute an interesting easily obtainable material to assess the effect of nutritional interventions on browning capacity.


Assuntos
Adipócitos Marrons/metabolismo , Tecido Adiposo Branco/metabolismo , Leucócitos Mononucleares/metabolismo , Obesidade/patologia , Animais , Diferenciação Celular , Dieta Hiperlipídica , Modelos Animais de Doenças , Regulação da Expressão Gênica , Masculino , Proteínas Mitocondriais , Ratos , Ratos Wistar , Transdução de Sinais , Termogênese
2.
Int J Obes (Lond) ; 37(9): 1169-76, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23207406

RESUMO

OBJECTIVE: To assess the influence of supplementation with a moderate dose of vitamin A in early life on adipose tissue development and the response to an obesogenic diet later in life. METHODS: During the suckling period, rat pups received a daily oral dose of retinyl palmitate corresponding to three times the vitamin A ingested daily from maternal milk. Control rats received the vehicle (olive oil). Short-term effects of treatment on gene expression and morphology of white adipose tissue (WAT) were analyzed in animals on the day after weaning (day 21). To study long-term effects, control and vitamin A-treated rats were fed, after weaning, a normal fat or a high-fat (HF) diet for 16 weeks. RESULTS: WAT of vitamin A-treated young rats (day 21) was enriched in small adipocytes with a reduced expression of adipogenic markers (peroxisome proliferator-activated receptor γ and lipoprotein lipase) and an increased cell proliferation potential as indicated by increased expression of proliferating cell nuclear antigen. Increased retinoic acid (RA)-induced transcriptional responses were present in the tissues of vitamin A-treated young rats (day 21) including WAT. Vitamin A-treated rats developed higher adiposity than control rats on a HF diet as indicated by body composition analysis and increased WAT depot mass, adipocyte diameter, WAT DNA content, leptinemia and adipose leptin gene expression. Excess adiposity gain in vitamin A-treated rats developed in the absence of changes in body weight and was attributable to excess adipocyte hyperplasia. No differences in adiposity were observed between vitamin A-treated rats and control rats on a normal fat diet. Total retinol levels in WAT of vitamin A-treated rats were elevated at weaning (day 21) and normalized by day 135 of age. CONCLUSION: Vitamin A intake in the early stages of postnatal life favors subsequent HF diet-induced adiposity gain through mechanisms that may relate to changes in adipose tissue development, likely mediated by RA.


Assuntos
Tecido Adiposo Branco/patologia , Adiposidade , Dieta Hiperlipídica , Vitamina A/análogos & derivados , Vitamina A/farmacologia , Desmame , Tecido Adiposo Branco/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos , Animais Lactentes/crescimento & desenvolvimento , Peso Corporal , Suplementos Nutricionais , Diterpenos , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Imuno-Histoquímica , Masculino , PPAR gama/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Ésteres de Retinil , Vitamina A/administração & dosagem , Vitamina A/efeitos adversos
6.
Am J Physiol Cell Physiol ; 279(3): C670-81, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10942717

RESUMO

Multilocular, mitochondria-rich adipocytes appear in white adipose tissue (WAT) of rats treated with the beta3-adrenoceptor agonist, CL-316243 (CL). Objectives were to determine whether these multilocular adipocytes derived from cells that already existed in the WAT or from proliferation of precursor cells and whether new mitochondria contained in them were typical brown adipocyte mitochondria. Use of 5-bromodeoxyuridine to identify cells that had undergone mitosis during the CL treatment showed that most multilocular cells derived from cells already present in the WAT. Morphological techniques showed that at least a subpopulation of unilocular adipocytes underwent conversion to multilocular mitochondria-rich adipocytes. A small proportion of multilocular adipocytes ( approximately 8%) was positive for UCP1 by immunohistochemistry. Biochemical techniques showed that mitochondrial protein recovered from WAT increased 10-fold and protein isolated from brown adipose tissue (BAT) doubled in CL-treated rats. Stained gels showed a different protein composition of new mitochondria isolated from WAT from that of mitochondria isolated from BAT. Western blotting showed new mitochondria in WAT to contain both UCP1, but at a much lower concentration than in BAT mitochondria, and UCP3, at a higher concentration than that in BAT mitochondria. We hypothesize that multilocular adipocytes present at 7 days of CL treatment have two origins. First, most come from convertible unilocular adipocytes that become multilocular and make many mitochondria that contain UCP3. Second, some come from a cell that gives rise to more typical brown adipocytes that express UCP1.


Assuntos
Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Agonistas Adrenérgicos beta/farmacologia , Dioxóis/farmacologia , Adipócitos/metabolismo , Adipócitos/ultraestrutura , Tecido Adiposo/citologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Animais , Linhagem Celular , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Mitocôndrias/ultraestrutura , Ratos , Ratos Sprague-Dawley
7.
Int J Obes Relat Metab Disord ; 24(6): 789-93, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10878688

RESUMO

BACKGROUND: Leptin plays an important role in the control of food intake and body weight homeostasis. In humans, leptin is produced by adipocytes, placental cells and secretory cells of the mammary epithelium. Recently, it has been reported that stomach glands produce leptin in rats. OBJECTIVE: To test the expression of leptin protein in human stomach and localize, by immunocytochemistry, the specific cell type producing leptin. DESIGN: Endoscopic stomach biopsies of six patients were used to investigate leptin production in the fundic epithelium using reverse transcription polymerase chain reaction (RT-PCR) of RNA. Leptin protein was detected by immunoblot analysis and localized by immunohistochemistry and ultrastructural immunocytochemistry (immunogold method). RESULTS: Human gastric epithelium expresses leptin mRNA and leptin protein. The cells in the lower half of the stomach glands were immunoreactive for leptin. Ultrastructural immunocytochemistry showed leptin immunoreactivity in the pepsinogen granules of chief cells, but the granules of a specific endocrine cell type in the basal portion of the glands were also positive. CONCLUSIONS: Our results suggest that gastric leptin could function in the short-term system to control feeding behaviour and is probably secreted in the stomach lumen by chief cells and into the stomach circulation by a special type of endocrine cell.


Assuntos
Celulas Principais Gástricas/ultraestrutura , Grânulos Citoplasmáticos/química , Glândulas Endócrinas/ultraestrutura , Mucosa Gástrica/ultraestrutura , Leptina/análise , Adulto , Western Blotting , Feminino , Humanos , Imuno-Histoquímica , Leptina/genética , Masculino , Microscopia Imunoeletrônica , Pessoa de Meia-Idade , Obesidade/metabolismo , Pepsinogênio A/análise , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
J Struct Biol ; 107(2): 128-35, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1807349

RESUMO

Tannic acid treatment was used to study the morphology of surfactant-like material (SLM) in the taste organ of Rana esculenta and the relation between this material and the cell types of the organ. On the surface of the taste organ SLM was associated with the apical processes of wing and putative taste cells. In SLM, a biphasic pattern was visible, a portion showed a lamellar periodicity (the repeating period of lamellae approximated 45 A), and a second portion showed an homogeneous electron density. Electron spectroscopic imaging revealed the presence of phosphorus and a large amount of calcium associated with the SLM. The result of our work suggests that SLM has a role in the perireceptorial events in the gustatory transduction by concentrating calcium in specific sites of the chemoreceptorial surface.


Assuntos
Tensoativos/análise , Papilas Gustativas/química , Animais , Cálcio/metabolismo , Microanálise por Sonda Eletrônica , Feminino , Taninos Hidrolisáveis/farmacologia , Masculino , Microscopia Eletrônica , Rana esculenta , Papilas Gustativas/efeitos dos fármacos , Papilas Gustativas/metabolismo , Papilas Gustativas/ultraestrutura
9.
Biomed Pharmacother ; 40(1): 28-32, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3486680

RESUMO

The term dysmyelopoietic syndrome (DMPS) covers a variety of closely related disorders with various etiological factors, and characterized by chronic (pan) cytopenias whose prognosis and treatment are still controversial. Despite the recent efforts to identify pathogens, effector cells and soluble cell products involved in the development of this syndrome only a few comprehensive experimental data are available, useful for elaboration of therapeutic regimens. We describe here a patient with DMPS who was refractory to inductive chemotherapy. Initial agar gel culture studies revealed the activity of hematopoiesis inhibitory T cells within the bone marrow that could be suppressed by prednisone both in vitro and in vivo. However another pathological cell features, the excess of an unusual lympho-reticular cell complexes was identified in long-term liquid cultures. These symbiotic cell complexes persisted throughout the disease, despite the prednisone induced hematological remission, suggesting their causative role in the disease, that more recently progressed towards acute myeloid leukemia.


Assuntos
Medula Óssea/patologia , Síndromes Mielodisplásicas/patologia , Adulto , Medula Óssea/ultraestrutura , Células Cultivadas , Feminino , Humanos , Microscopia Eletrônica , Prednisona/farmacologia , Reticulócitos/patologia , Linfócitos T/patologia , Fatores de Tempo , População Branca
10.
Blood ; 66(6): 1233-40, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2415185

RESUMO

A human eosinophilic leukemia cell line, designated as EoL, was established from the peripheral blood of a patient with Philadelphia chromosome-negative eosinophilic leukemia (EL). The EoL cell line grows in single cell suspension with a doubling time of 48 hours for about one year. The reactivity of these cells was tested with a panel of monoclonal antibodies; they were found to express surface IA antigen, myeloid antigen (IF10, MY9) and membrane receptors for interleukin 2 (IL-2, Tac antigen). Under standard culture conditions, a small percentage of cells having more typical eosinophilic characteristics was present. These cells had cytoplasmic granules and were positive for Luxol-fast-blue and eosinophil peroxidase. Under culture conditions to induce the maturation of myeloid cells, such as alkaline medium or addition of dimethyl sulfoxide (DMSO), the frequency of cells with typical eosinophilic features increased to about 40%. In addition, cytogenetic studies showed that cultured cells and original leukemic blasts presented similar chromosome abnormalities. EoL seems to be a unique leukemic line committed to the eosinophilic lineage and can provide a useful in vitro model for the study of malignant eosinophilic properties.


Assuntos
Leucemia/patologia , Adulto , Anticorpos Monoclonais/imunologia , Antígenos de Superfície/análise , Antígenos Virais/análise , Diferenciação Celular , Linhagem Celular , Células Cultivadas , Células Clonais , DNA Nucleotidilexotransferase/metabolismo , Eosinófilos/ultraestrutura , Herpesvirus Humano 4/imunologia , Humanos , Cariotipagem , Masculino , Microscopia Eletrônica , Formação de Roseta , Coloração e Rotulagem
11.
Boll Soc Ital Biol Sper ; 60(4): 805-10, 1984 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-6145433

RESUMO

The authors have observed with E.M. Philips 301 some biopsies obtained from testes of cryptorchid patients aged between 38 and 72 to study the ultrastructural aspects of seminiferous tubules in this age. Tissues were fixed in 2% phosphate-buffered solution of glutaraldehyde and then postfixed in 1% osmium tetroxide, processed for routine electron microscopy. The seminiferous tubules appear strongly damaged and we have observed numerous Sertoli cells and only few dark spermatogonia. The Sertoli cells appear either normal and mature or with a cytoplasm filled with big lipid droplets and large amounts of glycogen. The basal membrane of the seminiferous tubules is thickened. Leydig cells are characterized by dilated smooth endoplasmic reticulum and numerous nuclear bodies.


Assuntos
Criptorquidismo/patologia , Testículo/ultraestrutura , Adulto , Fatores Etários , Idoso , Biópsia , Humanos , Células Intersticiais do Testículo/ultraestrutura , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Túbulos Seminíferos/ultraestrutura , Células de Sertoli/ultraestrutura
13.
Boll Soc Ital Biol Sper ; 59(4): 418-24, 1983 Apr 30.
Artigo em Italiano | MEDLINE | ID: mdl-6882535

RESUMO

Periepidydimal fat pad of young rat shows, in the peripheral zone, areas with lobular aspect and areas with flattened aspect, surrounded by a mesothelial sheath. In adult rats the flattened areas are no longer observed. The ultrastructural study of the cells present in the flattened zones of the periepidydimal fat pad and the comparison with the same tissue of adult rats seems to indicate that the flattened areas in the peripheral zone of the periepidydimal fat pad of the young rat are a site where the adipocyte precursors can best be studied. Furthermore in the pericytes of the blood vessels wall, rare little lipid vacuoles can be seen: this is in accordance with the hypothesis proposed by other autøhors that the precursors of the adipocytes derive from pericytes.


Assuntos
Tecido Adiposo/ultraestrutura , Envelhecimento , Animais , Epididimo/ultraestrutura , Masculino , Microscopia Eletrônica , Mitose , Ratos , Ratos Endogâmicos
14.
Arch Sci Biol (Bologna) ; 62(1-4): 1-11, 1978.
Artigo em Italiano | MEDLINE | ID: mdl-555322

RESUMO

Daily variations of serum and urine calcium and phosphate were determined in young and adult rats of both sexes. The animals were maintained in natural conditions of illumination and feeding ad libitum. The twenty-four hour rhythm of the serum levels and urinary excretion of these electrolytes in male rats is confirmed. This rhythm is markedly modified in young females and less in adult females. Evidence for a circadian rhythm of the Ca/PO4 ratio appears in all groups of rats. The rhythms of serum and urine Ca/PO4 rations are similar in all experimental groups.


Assuntos
Cálcio/análise , Ritmo Circadiano , Fosfatos/análise , Fatores Etários , Animais , Cálcio/sangue , Cálcio/urina , Feminino , Masculino , Fosfatos/sangue , Fosfatos/urina , Ratos , Fatores Sexuais
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