RESUMO

Obesity is accompanied by chronic inflammation of VAT, which promotes metabolic changes, and purinergic signaling has a key role in a wide range of inflammatory diseases. Therefore, we addressed whether fat inflammation could be differentially modulated by this signaling pathway in the MUO and in individuals who remain MHO. Our results show that the necrotized VAT of both groups released greater levels of ATP compared with lean donors. Interestingly, MUO tissue SVCs showed up-regulation and engagement of the purinergic P2X7R. The extracellular ATP concentration is regulated by an enzymatic process, in which CD39 converts ATP and ADP into AMP, and CD73 converts AMP into adenosine. In VAT, the CD73 ectoenzyme was widely distributed in immune and nonimmune cells, whereas CD39 expression was restricted to immune CD45PAN+ SVCs. Although the MUO group expressed the highest levels of both ectoenzymes, no difference in ATP hydrolysis capacity was found between the groups. As expected, MUO exhibited the highest NLRP3 inflammasome expression and IL-1ß production. MUO SVCs also displayed up-regulation of the A2AR, allowing extracellular adenosine to increase IL-1ß local secretion. Additionally, we demonstrate that metabolic parameters and BMI are positively correlated with purinergic components in VAT. These findings indicate that purinergic signaling is a novel mechanism involved in the chronic inflammation of VAT underlying the metabolic changes in obesity. Finally, our study reveals a proinflammatory role for adenosine in sustaining IL-1ß production in this tissue.

RESUMO

A isquemia miocárdica é o evento fisiopatológico final da doença arterial coronária (DAC). Quando desprovida de sintomatologia é denominada "isquemia miocárdica silenciosa", sendo a responsável pela maior parte dos eventos isquêmicos totais. Ainda permanecem incertos os porquês da näo percepçäo dolorosa ("angina") de certos episódios isquêmicos, bem como dos mecanismos fisiopatológicos que as desencadeiam. Claro está, no entanto, que os eventos silenciosos e sintomáticos näo se diferem quanto às alteraçöes miocárdicas estruturais e funcionais. O diagnóstico de isquemia silenciosa se estabelece quando da detecçäo de alteraçöes objetivas e características de dano miocárdico isquêmico. Dentre os métodos se configuram, principalmente, a eletrocardiografia de esforço, a monitorizaçäo eletrocardiográfica ambulatorial, o teste de perfusäo com tálio-201 e o ecocardiograma de esforço. Há outros, porém de menor utilizaçäo. Destaca-se a isquemia silenciosa pela sua importante relaçäo com o prognóstico dos portadores de DAC. Muitos estudos relatam participaçäo significativa daquela nos variados desfechos da DAC (angina, infarto agudo do miocárdio e morte súbita). O enfoque terapêutico varia para cada paciente, podendo iniciar-se com a mudança do estilo de vida (alteraçäo dos fatores de risco). A terapêutica medicamentosa se baseia na utilizaçäo de drogas antiisquêmicas (nitratos, beta-bloqueadores e antagonistas dos canais de cálcio) e antiplaquetários. o tratamento mais agressivo inclui a angioplastia coronária, a colocaçäo de stents e a cirurgia de revascularizaçäo do miocárdio.

Assuntos

RESUMO

We report a study carried out in three livestock-producing regions of Venezuela to determine the mineral status of grazing cattle and its relationship to the Síndrome Parpléjico del Bovino (SPB). Animal tissue samples from blood and liver were collected from a total of 17 farms within three regions: southwest (Apure), central (Guárico) and southeast (Bolívar) both during the dry and rainy seasons. In SPB free animals, the serum levels of sodium, potassium, chloride, magnesium, total and ionized calcium, phosphorus, and creatinine, were within the normal range. Glucose was found to be deficient in cattle from Bolívar and Guárico states and normal in Apure. With the exception of liver copper and serum zinc, all the other microelements analyzed (liver cobalt, and molybdenum, and serum iron) were found to be normal. Copper was found to be low in all regions studied with a mean value of 74.8 ppm indicating a moderate deficiency of this element. Similarly, in the central and southwest regions, zinc was found to be close to 0.34 ppm, significantly lower than the critical level of 0.7 ppm. In order to determine the effect of the dry and rainy seasons on the content of macro and microelements, controlled group of cattle from the three regions were followed in their contents of magnesium, calcium, copper and iron. In the dry season all of these elements tended to be much lower, showing a significant increase in the rainy season. This increase was much greater in cattle that received mineral supplementation and sanitary treatment. Bovines with diagnosis of SPB showed: low liver copper content, low serum magnesium and phosphorus levels significantly higher that control cattle.

Assuntos