997 resultados para Fator de crescimento semelhante à insulina tipo I


Relevância:

100.00% 100.00%

Publicador:

Resumo:

The follicular growth and oocyte maturation knowledge are very important to the development and improvement of new biotechnologies such as in vitro fertilization and somatic cell nuclear transfer. In order to the necessity of clarify the basic mechanisms related to canine oocyte maturation, this investigation focuses on the evaluation of the effect of insulin-like growth factor-i (IGF-I), added to synthetic oviductal fluid medium (SOF) on the in vitro maturation of domestic dog oocytes. Thirty-seven bitches undergoing ovariohysterectomy for castration or due to pathological conditions of the uterus were selected as oocytes' donors (n=875). The oocytes were allocated in the following groups: MO (stained in the collection's time), Control (72h in SOF) and Experimental (72h in SOF plus 100 ng IGF-I). After 72 hours of maturation the oocytes' nuclear status were assessed by Hoechst 33342 dye. The best results in terms of oocyte harvest were observed in those juvenile donors,, females in estrus, nuliparous and pure breeds. No significant differences were observed between treatments control (SOF) or experimental (IGF-I).

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Ciências Biológicas (Farmacologia) - IBB

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

O hormônio de crescimento (GH), principal regulador do crescimento pós-natal, tem importantes ações metabólicas em diferentes tecidos, sinérgicas ou até antagônicas às do fator de crescimento semelhante à insulina tipo I (IGF-I), produzido sobretudo no fígado após ligação do GH ao seu receptor. Experimentos em modelos animais indicam um papel importante do GH na resistência a insulina, enquanto o papel do IGF-I nessa condição ainda não está completamente elucidado. Em humanos, o GH promove aumento da lipólise e da oxidação lipídica, enquanto o IGF-I desencadeia o aumento da oxidação lipídica apenas cronicamente. Enquanto as ações sobre o crescimento são tempo limitado, as ações metabólicas e cardiovasculares do eixo GH/IGF-I perduram durante toda a vida. Os potenciais efeitos anabólicos do GH têm sido utilizados em condições crônicas e hipercatabólicas, embora as investigações sobre os desfechos clínicos ainda sejam escassas. Neste artigo, pretendemos revisar as ações metabólicas do GH oriundas de modelos animais, os estudos em humanos normais e indivíduos com deficiência de GH, diabete melito tipo 1, síndrome metabólica, estados hipercatabólicos e a relação do eixo GH/IGF-I com as adipocinas, disfunção endotelial e aterogênese

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Milk intake is widely recommended for a healthy diet. Recent evidences suggest that milk/dairy products are associated with a lower risk of type 2 diabetes and hypertension. On the other hand, high calcium intake has been associated with a higher risk of prostate cancer. The calcium and vitamin D content in dairy foods could have beneficial effects on glucose metabolism and renin/angiotensin system as well regulates body weight. The association between high dairy/calcium consumption and prostate cancer risk are related to the presence of estrogens and insulin like growth factor (IGF-I) in milk. Based on the current evidence, it is possible that milk/dairy products, when consumed in adequate amounts and mainly with reduced fat content, has a beneficial effect on the prevention of hypertension and diabetes. Its potential role in the pathogenesis of prostate cancer is not well supported and requires additional study.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

O mastocitoma cutâneo (MTC) é a neoplasia maligna mais comum na pele dos cães e seu comportamento biológico é muito variável. Dentre os fatores prognósticos estudados nos MTCs, a classificação histopatológica, o índice proliferativo e o padrão de expressão doc-KIT são os que apresentam uma associação mais relevante com o provável prognóstico deste tumor. O objetivo deste trabalho foi avaliar a expressão proteica de fator de crescimento semelhante à insulina tipo 1 (IGF-1), fator de célula tronco (SCF) e sua relação com o receptor tirosina quinase (c-KIT), alvo da rapamicina em mamíferos (m-TOR), grau histológico, índice proliferativo pelo KI-67e o número de figuras de mitose (IM) com dados clínicos de cães com MTCs . Foram utilizadas 133 amostras de MTCs, provenientes de 133 cães, dispostas em lâminas de microarranjo de tecidos (TMA). A técnica de imuno-histoquímica foi utilizada para a avaliação destas proteínas. Observou-se associação entre SCF e, a graduação histopatológica proposta em 2011, índice mitótico, proliferação celular (KI-67), escore de IGF-1, local da lesão, idade dos animais e padrão imuno-histoquímico do receptor c-KIT. A relação de dependência também foi observada entre IGF-1 e o porte dos animais, IM, m-TOR e c-KIT. A expressão de SCF teve relacção com a agressividade dos MTCs caninos, uma vez que foi mais freqüente em MTCs com c-KIT citoplasmático. A relação entre a expressão de IGF-1, SCF, c-KIT e m-TOR pode estar associada à integralização de suas vias de ação. A expressão de IGF-1 está associada à MTCs em cães de porte grande.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Adequate testosterone levels are necessary for the development, growth and maintenance of the male reproductive system. Testosterone deficiency is common in men with diabetes in whom it may contribute to impaired performance, with consequent reduction of the activity of the androgen regulated organs, such as the prostate. However, little attention has been given to the plasma dihydrotestosterone (DHT) level, the most potent androgen, nor to the expression of the androgen receptor (AR), insulin-like growth factor type I (IGF-1) and receptor (IGF-1R) in target tissues. Here, we investigated the effect of type I diabetes mellitus on DHT plasma levels and on prostate AR, IGF-1 and IGF-1R expression during rat pubertal growth. Diabetes was induced in prepubertal male rats through administration of streptozotocin (STZ; 40 mg/kg). Diabetic, diabetic treated with insulin, and age-matched control animals were killed by overdoses of pentobarbital. The ventral prostatic lobe (VP) was dissected, weighed and processed for immunohistochemistry for AR, IGF-1 e IGF-1R; plasma T and DHT levels were also determined. Hyperglycemia at puberty reduced VP weight gain to about 50% and plasma T level to about 80% of the control levels. In contrast there were no changes in plasma DHT levels. Insulin replacement restored the VP weight gain, but not the plasma T levels, which remained 90% below the ones of controls. Immunohistochemistry showed that AR, IGF-1 and IGF-1R expression in the prostate epithelial cells did not change with hyperglycemia or insulin replacement. Thus, the AR expression in the prostate epithelial cells appears to be regulated by DHT, and to a minor extent it also controls glandular growth

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This study aimed to investigate the independent and additive effects of counter-resistance training (RT) and soy isoflavone supplement (ISO) on bone mineral density (BMD) and bone turnover in postmenopausal women. This study used a placebo-controlled, double-blinded (soy), randomized two (ISO vs. placebo) x two (RT vs. no RT) design. Eighty sedentary postmenopausal women, aged 45-70 years, were randomly assigned to one of four groups (71 completed a 9-month intervention): RT+ISO (n=15); no RT+ISO (n=20); RT+placebo (n=18); no RT+placebo (n=18). Participants randomized to ISO received 100mg/ day/oral of soy isoflavone; and those to RT attended supervised counter-resistance training sessions at least twice a week. At baseline and 9-month, BMD was estimated by dual-energy X-ray absorptiometry (DXA). Serum levels of C-terminal cross-linked telopeptide of type I collagen (CTX), osteocalcin, and insulin-like growth factor-1 (IGF-1) were measured as bone turnover. ANOVA with time as the repeated measure and test t were used in the statistical analysis. After 9 months of intervention, neither ISO nor RT alone affected BMD at any site or levels of CTX, osteocalcin, and IGF-1 (p>0.05). ISO and RT had no additive effects on BMD and bone turnover. RT groups showed significantly increased muscle strength (+ 35.2%) (p=0.02). We found no additive effects of resistance training and soy isoflavone on bone mineral density or bone turnover in postmenopausal women after 9-months.