Modulação dos receptores de hormônio tireoidiano, TRα e TRβ, utilizando diferentes doses de triiodotironina (T3) em diferentes tempos

OBJECTIVE: To examine the effect of different doses of triiodothyronine (T3) on mRNA levels of thyroid hormone receptors, TRα and TRβ, at different times. MATERIALS AND METHODS: 3T3-L1 adipocytes were incubated with T3 (physiological dose: F; supraphysiological doses: SI or SII), or without T3 (control, C) for 0.5, 1, 6, or 24h. TRα and TRβ mRNA was detected using real-time polymerase chain reaction. RESULTS: F increased TRβ mRNA levels at 0.5h. After 1h, TRα levels increased with F and SI and TRβ levels decreased with SII compared with C, F, and SI. After 6h, both genes were suppressed at all concentrations. In 24h, TRα and TRβ levels were similar to those of C group. CONCLUSIONS: T3 action with F began at 1h for TRα and at 0.5h for TRβ. These results suggest the importance of knowing the times and doses that activate T3 receptors in adipocytes.OBJETIVO: Examinar o efeito de diferentes doses de triiodotironina (T3) sobre a expressão gênica dos receptores TRα e TRβ em diferentes tempos. MATERIAIS E MÉTODOS: Adipócitos, 3T3-L1, foram incubados com T3 nas doses fisiológica (F, 10nM) e suprafisiológicas (SI, 100nM ou SII, 1000nM) ou veículo (controle, C) durante 0,5, 1, 6 ou 24h. mRNA dos TRs foram detectados utilizando PCR em tempo real. RESULTADOS: Níveis de TRβ aumentaram em F em 0,5h. Após 1h, níveis de TRα aumentaram em F e SI comparado ao C, enquanto TRβ diminuiu no SII comparado com C, F, e SI. Após 6h, ambos os genes foram suprimidos em todas concentrações. Em 24h, níveis de TRα e TRβ retornaram aos do C. CONCLUSÕES: Ação do T3 em F iniciou-se em 1h para TRα e 0,5h para TRβ. Esses resultados são importantes para determinar tempo inicial e dose de T3 em que os receptores de HT são ativados em adipócitos.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Unesp Botucatu Medicine School Department of Internal ClinicUniversidade Federal de São Paulo (UNIFESP) Department of PhysiologyUnesp Biosciences Institute Department of BiostatisticsUNIFESP, Department of PhysiologySciEL

Isolation and enzyme bioprospection of endopytic bacteria associated with plants of Brazilian mangrove ecosystem

The mangrove ecosystem is a coastal tropical biome located in the transition zone between land and sea that is characterized by periodic flooding, which confers unique and specific environmental conditions on this biome. In these ecosystems, the vegetation is dominated by a particular group of plant species that provide a unique environment harboring diverse groups of microorganisms, including the endophytic microorganisms that are the focus of this study. Because of their intimate association with plants, endophytic microorganisms could be explored for biotechnologically significant products, such as enzymes, proteins, antibiotics and others. Here, we isolated endophytic microorganisms from two mangrove species, Rhizophora mangle and Avicennia nitida, that are found in streams in two mangrove systems in Bertioga and Cananéia, Brazil. Bacillus was the most frequently isolated genus, comprising 42% of the species isolated from Cananéia and 28% of the species from Bertioga. However, other common endophytic genera such as Pantoea, Curtobacterium and Enterobacter were also found. After identifying the isolates, the bacterial communities were evaluated for enzyme production. Protease activity was observed in 75% of the isolates, while endoglucanase activity occurred in 62% of the isolates. Bacillus showed the highest activity rates for amylase and esterase and endoglucanase. To our knowledge, this is the first reported diversity analysis performed on endophytic bacteria obtained from the branches of mangrove trees and the first overview of the specific enzymes produced by different bacterial genera. This work contributes to our knowledge of the microorganisms and enzymes present in mangrove ecosystems

Experimental Hyperthyroidism Decreases Gene Expression and Serum Levels of Adipokines in Obesity

Aims. To analyze the influence of hyperthyroidism on the gene expression and serum concentration of leptin, resistin, and adiponectin in obese animals. Main Methods. Male Wistar rats were randomly divided into two groups: control (C)—fed with commercial chow ad libitum—and obese (OB)—fed with a hypercaloric diet. After group characterization, the OB rats continued receiving a hypercaloric diet and were randomized into two groups: obese animals (OB) and obese with 25 μg triiodothyronine (T3)/100 BW (OT). The T3 dose was administered every day for the last 2 weeks of the study. After 30 weeks the animals were euthanized. Samples of blood and adipose tissue were collected for biochemical and hormonal analyses as well as gene expression of leptin, resistin, and adiponectin. Results. T3 treatment was effective, increasing fT3 levels and decreasing fT4 and TSH serum concentration. Administration of T3 promotes weight loss, decreases all fat deposits, and diminishes serum levels of leptin, resistin, and adiponectin by reducing their gene expression. Conclusions. Our results suggest that T3 modulate serum and gene expression levels of leptin, resistin, and adiponectin in experimental model of obesity, providing new insights regarding the relationship between T3 and adipokines in obesity

Endobronchial myxoma: Case report

INTRODUCTION: Pulmonary myxoma is an extremely rare benign neoplasm. It is mostly parenchymal but may occasionally occur within the tracheobronchial tree. There are very few reports of endobronchial myxoma. CASE REPORT: We describe a case of endobronchial myxoma in a 40-year-old female patient with a history of asthma and repeated right-sided pneumonia. Thoracic computed tomography (CT) showed medium lobe atelectasis. Fiber optic bronchoscopy revealed a polypoid, well-circumscribed tumor, causing total obstruction of the medium lobe bronchus. Biopsy of the mass was non-diagnostic. Further study included a positron emission tomography (PET) which demonstrated low metabolic activity of the tumor and no evidence of neoplasia in other location. The patient was submitted to a medium lobectomy and microscopic examination of the tumor revealed myxoid stroma with lobulated pattern, elongated and stellate cells, compatible with myxoma. CONCLUSION: Pulmonary myxoma is extraordinary rare and endobronchial location is very few reported in medical literature

Óleo-resina de copaíba diminui o índice de adiposidade e melhora o sistema redox, os níveis de IL-10 e função renal de ratos submetidos à dieta rica em sacarose

Alterações nos hábitos alimentares levam a maior risco de desenvolver obesidade e outras doenças crônicas, como disfunção renal. Produtos naturais podem apresentar potencial terapêutico, sendo importante avaliar os efeitos desses compostos. Objetivou-se avaliar o efeito do óleo-resina de copaíba sobre os rins de ratos submetidos à dieta rica em sacarose. Para isso, ratos Wistar machos foram casualmente divididos para receberem dieta padrão e solução de sacarose (30%) (S, n=8) ou dieta padrão e solução de sacarose (30%) e suplementação com óleo-resina de copaíba (200 mg/kg/dia, via gavagem) (S+OC, n=8), por 8 semanas. Ao final do experimento, foram avaliados ganho de peso, índice de adiposidade, peso dos rins, marcadores do estado redox e níveis de citocinas. A análise estatística foi realizada por teste t de Student, com nível de significância de P<0,05. Foi observado que a suplementação com óleo-resina de copaíba foi eficiente em reduzir o ganho de peso e índice de adiposidade. Não houve diferença no peso dos rins entre os grupos. A suplementação com óleo-resina não alterou os níveis de ureia, contudo, diminuiu os níveis de creatinina, foi capaz de aumentar os níveis de IL-10, a atividade das enzimas CAT e SOD, e reduzir os marcadores de dano oxidativo. Assim, conclui-se que o óleo-resina de copaíba reduz o índice de adiposidade, o qual foi associado a melhora do estado redox, ao aumento de IL-10 e à melhor função renal, sugerindo que o óleo-resina de copaíba apresenta efeitos benéficos sobre os rins de animais submetidos à dieta rica em sacarose

Inter-relação da leptina e dos hormônios tireoidianos na perda de peso de ratos obesos

A obesidade é uma doença crônica, multifatorial que leva ao aumento do risco de desenvolver outras doenças. É freqüentemente considerada como uma doença do estilo de vida, causada pela escolha errônea dos alimentos e pela diminuição da atividade física, sendo a restrição calórica a prática mais comum para tratar a obesidade. Em humanos, a perda de peso está associada com redução de fatores de risco para doenças cardiovasculares, diminuição da taxa de incidência de Diabetes Mellitus tipo 2 e aumento da qualidade de vida. O peso corporal é regulado por uma interação complexa entre hormônios e neuropeptídeos. A leptina e os hormônios tireoidianos (HT) estão envolvidos na regulação do balanço energético. Objetivo: Analisar, em ratos, a inter-relação entre leptina e hormônios tireoidianos na obesidade e na perda de peso. Metodologia: Foram utilizados ratos Wistar machos, com 30 dias de idade, separados em dois grupos, Controle (C) e Obeso (OB). Os animais C receberam ração comercial Labina e os do grupo OB um ciclo de dietas hipercalóricas por 15 semanas. Após o período de indução de obesidade, os animais OB foram novamente separados em outros 3 grupos, OB; animais com restrição alimentar (RIA); e animais com restrição mais administração de Hormônio Tireoidiano (RHT) na dose de 5 mg/100g de peso do animal. Os animais OB receberam as dietas hipercalóricas até o final do experimento, enquanto os animais RIA e RHT receberam 75% do total consumido pelo grupo C de dieta comercial, por 28 dias. Após este período, os animais RIA continuaram, somente, com a restrição alimentar e os RHT receberam além da restrição...Obesity is a chronic multifactor disease which brings increased risk of developing other diseases. It is frequently considered as a lifestyle disease, caused by choosing the wrong foods and reducing physical activity, with calorie restriction being the commonest way of treating it. Weight loss in humans is associated with reduced risk factors for cardiovascular disease, reduced incidence of type II Diabetes Mellitus, and increased quality of life. Bodyweight is regulated by a complex interaction between hormones and neopeptides. Leptin and the thyroid hormones (TH) are involved in regulating the energy balance. Objective: To analyze the interrelation in rats between leptin and thyroid hormones in obesity and weight loss. Methodology: Male 30-day-old Wistar rats were separated into two groups, Control (C) and Obese (OB). Control animals received commercial Labina rat food and the OB group a cycle of hypercaloric diets for 15 weeks. After the induced obesity period, the OB animals were separated into three subgroups; OB hypercaloric diet; RIA food restriction; RHT food restriction plus 5mg/100g body weight thyroid hormone. OB animals received the hypercaloric diets until the end of the experiment, where the RIA and RHT animals received 75% the total commercial food consumed by the control group for 28 days. After this period, the RIA animals continued with food restriction only, and the RHT animals received food restriction plus a dose of TH for 28 days. At each phase of the experiment, five animals from each group were sacrificed to analyze gene expression of leptin and TRb in adipose tissue using semiquantitative RT-PCR. Results: The OB animals showed increased weight and adipose tissue, lipid and glycemia profile changes, and increased plasmatic... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Influência de diferentes doses suprafisiológicas de triidotironina sobre adipocinas na obesidade e após a perda de peso

Obesidade, uma alteração do estado nutricional, é definida como um acúmulo excessivo ou anormal de tecido adiposo que pode deteriorar a saúde. O tecido adiposo participa ativamente na regulação de energia corporal. As células adiposas produzem várias substâncias biologicamente ativas, as adipocinas, com diferentes funções fisiológicas. A disfunção dos adipócitos, como ocorre na obesidade, pode alterar a liberação de adipocinas, como leptina, resistina e adiponectina. A restrição calórica afeta a regulação da expressão gênica do tecido adiposo, normalizando as alterações das adipocinas causadas pela obesidade; entretanto, este mecanismo ainda é pouco conhecido. Sabe-se que resistina, adiponectina, leptina e hormônios tireoidianos estão envolvidos na regulação do balanço energético. Entretanto, não é bem estabelecido os efeitos do hipertireoidismo sobre as adipocinas em ratos obesos e obesos submetidos à restrição calórica. O objetivo deste estudo foi analisar a influência de diferentes doses de triiodotironina (T3) sobre a concentração sérica e expressão gênica de leptina, resistina e adiponectina em animais obesos e obesos submetidos à restrição calórica. Para isto, foram utilizados ratos Wistar machos separados inicialmente em controle (C) e obeso (OB). Os animais C receberam dieta padrão e os OB receberam dieta hipercalórica por 20 semanas. Após o período de indução de obesidade, os animais OB foram randomizados em grupo obeso (OB), obeso com dose de 5 μg de T3/100g de peso do animal (OS1), obeso com dose de 25 μg de T3/100g de peso do animal (OS2), obeso submetido à restrição calórica (RC), RC com dose de 5 μg de T3/100g de peso do animal (RS1) e RC com dose de 25 μg de T3/100g de peso do animal (RS2). Os grupos restritos receberam 75% do...Obesity, an alteration of the nutritional state, is defined as an excessive or abnormal accumulation of adipose tissue that can cause health to deteriorate. Adipose tissue actively participates in the regulation of bodily energy. Adipose cells produce several biologically active substances, including adipokines, with different physiological functions. Dysfunction of adipocytes, as occurs in obesity, can alter the release of adipokines such as leptin, resistin and adiponectin. Calorie restriction affects the regulation of gene expression of adipose tissue, normalizing the alterations of adipokines caused by obesity; however, this mechanism remains poorly understood. It is known that resistin, adiponectin, leptin and thyroidal hormones are involved in the regulation of energetic balance. However, the effects of hyperthyroidism on adipokines in obese rats, submitted and not submitted to calorie restriction, are not well established. The present study aimed to analyze the influence of different doses of triiodothyronine (T3) on the serum concentration and gene expression of leptin, resistin and adiponectin in obese animals, submitted and not submitted to calorie restriction. Were used male Wistar rats initially separated into control (C) and obese (OB) groups. The C animals received control diet while OB received hypercaloric diet for 20 weeks. After the obesity-induction period the OB animals were randomly divided into obese (OB), obese with 5 μg dose of T3/100g animal body weight (OS1), obese with 25 μg dose of T3/100g body weight (OS2), obese submitted to calorie restriction (CR), CR with 5 μg dose of T3/100g body weight (RS1) and CR with 25 μg does of T3/100g body weight (RS2). The restricted groups received 75% of control group food consumption for 8 weeks. After this period, animals OS1, OS2, RS1 and ... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Thyroid hormone status interferes with estrogen target gene expression in breast cancer samples in menopausal women

We investigated thyroid hormone levels in menopausal BrC patients and verified the action of triiodothyronine on genes regulated by estrogen and by triiodothyronine itself in BrC tissues. We selected 15 postmenopausal BrC patients and a control group of 18 postmenopausal women without BrC. We measured serum TPO-AB, TSH, FT4, and estradiol, before and after surgery, and used immunohistochemistry to examine estrogen and progesterone receptors. BrC primary tissue cultures received the following treatments: ethanol, triiodothyronine, triiodothyronine plus 4-hydroxytamoxifen, 4-hydroxytamoxifen, estrogen, or estrogen plus 4-hydroxytamoxifen. Genes regulated by estrogen (TGFA, TGFB1, and PGR) and by triiodothyronine (TNFRSF9, BMP-6, and THRA) in vitro were evaluated. TSH levels in BrC patients did not differ from those of the control group (1.34 ± 0.60 versus 2.41 ± 1.10  μ U/mL), but FT4 levels of BrC patients were statistically higher than controls (1.78 ± 0.20 versus 0.95 ± 0.16 ng/dL). TGFA was upregulated and downregulated after estrogen and triiodothyronine treatment, respectively. Triiodothyronine increased PGR expression; however 4-hydroxytamoxifen did not block triiodothyronine action on PGR expression. 4-Hydroxytamoxifen, alone or associated with triiodothyronine, modulated gene expression of TNFRSF9, BMP-6, and THRA, similar to triiodothyronine treatment. Thus, our work highlights the importance of thyroid hormone status evaluation and its ability to interfere with estrogen target gene expression in BrC samples in menopausal women