Effect of yerba mate and green tea on paraoxonase and leptin levels in patients affected by overweight or obesity and dyslipidemia: a randomized clinical trial.

BACKGROUND: This study aimed to evaluate the effect of the intake of yerba mate (YM) and green tea (GT) on serum levels of leptin and paraoxonase-1 (PON-1), compared to control. METHODS: Controlled, randomized clinical trial (RCT) that evaluated 142 men and women affected by overweight or obesity aged 35-60 years, untreated dyslipidemia and no history of coronary artery disease. Participants were randomized to ingest 1000 mL GT, YM or apple tea (AT, control group) daily, during eight weeks. Serum PON-1 and leptin levels were analyzed by ELISA immunoassay at the beginning (baseline) and after eight weeks of intervention. RESULTS: The intake of 1 l of YM/day resulted in significant increase in serum levels of PON-1 (9.7%; p = 0.005). The consumption of GT induced no significant difference in the levels of PON-1 (p = 0.154) and leptin (p = 0.783). Intergroup analysis showed a significant difference (p = 0.036) in the variation of PON-1 levels in the YM group when compared to GT and AT groups. In addition, the increase in PON-1 levels in the YM group was significantly associated with increased HDL-c (p = 0.004). CONCLUSIONS: The intake of yerba mate increased the antioxidant capacity by increasing serum levels of PON-1 and was positively associated with increased HDL-c, stressing the protective role of this beverage against atherosclerotic diseases. GT intake had no significant effect on serum levels of PON-1 and leptin. TRIAL REGISTRATION: This study is registered with ClinicalTrials.gov under protocol number NCT00933647.

Characterization of a commercial cellulase for hydrolysis of agroindustrial substrates.

This work is focused on the characterization of a commercial cellulase in terms of optimum pH and temperature, stability to pH and temperature and affinity of this enzyme to several substrates, determining the Michaelis-Menten parameters. Maximum activity of cellulase was obtained for the temperature range from 40 to 50 °C and pH from 5.2 to 5.5. Enzyme activity decreased only 15% after 150 h of reaction at temperatures between 30 and 50 °C. No loss of activity was observed at pH 5.0 and 5.5. The cellulase showed satisfactory results in the hydrolysis of agroindustrial substrates, since similar activity was verified on filter paper and other agroindustrial substrates.

Relationship between adiponectin, obesity and insulin resistance.

OBJECTIVES: the conditions of obesity and overweight pose a major risk for a number of comorbidities, including clinical syndromes resulting from atherosclerotic disease. Recent studies strongly indicate that adipose tissue is an active endocrine organ that secretes bioactive factors such as adipokines. Adiponectin appears to have a regulatory role in the mechanism of insulin resistance and in the development of atherosclerosis. This systematic review aims to evaluate the anti-atherogenic effects of adiponectin and its properties to improve and mimic metabolic and vascular actions of insulin and its influence on endothelial function. METHODS: a qualitative, exploratory and literature review was performed in the PubMed, Portal Capes and Scielo databases using as key-words "adiponectin", "obesity", "insulin resistance", "anti-inflammatory", "therapeutic strategies" and "future prospects". RESULTS: evidence suggests that adiponectin has anti-atherogenic properties with anti-inflammatory effects on the vascular wall. Moreover, it modifies the vascular intracellular signaling and has indirect antioxidant effects on the human myocardium. On the other hand, there are studies suggesting that increased levels of adiponectin are paradoxically associated with a worse prognosis in heart failure syndrome, although the mechanisms are not clear. CONCLUSION: it is not clear whether adiponectin levels have any clinical significance for risk stratification in cardiovascular disease or if they simply reflect the activation of complex underlying mechanisms. Changes in lifestyle and some drug treatments for hypertension and coronary heart disease have shown significant effect to increase adiponectin levels, and simultaneously decrease in insulin resistance and endothelial dysfunction.

Relationship between adiponectin, obesity and insulin resistance / Relação entre adiponectina, obesidade e resistência à insulina

Objectives: the conditions of obesity and overweight pose a major risk for a number of comorbidities, including clinical syndromes resulting from atherosclerotic disease. Recent studies strongly indicate that adipose tissue is an active endocrine organ that secretes bioactive factors such as adipokines. Adiponectin appears to have a regulatory role in the mechanism of insulin resistance and in the development of atherosclerosis. This systematic review aims to evaluate the anti-atherogenic effects of adiponectin and its properties to improve and mimic metabolic and vascular actions of insulin and its influence on endothelial function. Methods: a qualitative, exploratory and literature review was performed in the PubMed, Portal Capes and Scielo databases using as key-words "adiponectin", "obesity", "insulin resistance", "anti-inflammatory", "therapeutic strategies" and "future prospects". Results: evidence suggests that adiponectin has anti-atherogenic properties with anti-inflammatory effects on the vascular wall. Moreover, it modifies the vascular intracellular signaling and has indirect antioxidant effects on the human myocardium. On the other hand, there are studies suggesting that increased levels of adiponectin are paradoxically associated with a worse prognosis in heart failure syndrome, although the mechanisms are not clear. Conclusion: it is not clear whether adiponectin levels have any clinical significance for risk stratification in cardiovascular disease or if they simply reflect the activation of complex underlying mechanisms. Changes in lifestyle and some drug treatments for hypertension and coronary heart disease have shown significant effect to increase adiponectin levels, and simultaneously decrease in insulin resistance and endothelial dysfunction. .

Objetivos: as condições de obesidade e sobrepeso representam um grande risco para uma série de comorbidades, incluindo as síndromes clínicas decorrentes da doença aterosclerótica. Recentes estudos indicam fortemente que o tecido adiposo é um órgão endócrino ativo que secreta fatores bioativos, como as adipocinas. A adiponectina parece ter um papel regulador no mecanismo da resistência à insulina e no desenvolvimento da aterosclerose. Este estudo de revisão tem como objetivo avaliar os efeitos antiaterogênicos da adiponectina e suas propriedades para melhorar e reproduzir ações metabólicas e vasculares de insulina e sua influência na função endotelial. Métodos: revisão qualitativa, exploratória e bibliográfica foi realizada nas bases de dados PubMed, Portal Capes e Scielo utilizando os unitermos "adiponectin", "obesity", "insulin resistance", "anti-inflammatory", "therapeutic strategies" e "future prospects". Resultados: evidências sugerem que a adiponectina tem propriedades antiaterogênicas com efeitos anti-inflamatórios sobre a parede vascular. Além disso, modifica a sinalização vascular intracelular e exerce efeitos antioxidantes indiretos sobre o miocárdio humano. Por outro lado, existem estudos que sugerem que níveis aumentados de adiponectina são paradoxalmente associados com pior prognóstico na síndrome de insuficiência cardíaca, embora os mecanismos ainda não estejam claros. Conclusão: é incerto se os níveis de adiponectina têm algum significado clínico para a estratificação de risco na doença cardiovascular ou se simplesmente refletem a ativação dos mecanismos complexos subjacentes. Modificações de estilo de vida e alguns tratamentos medicamentosos para hipertensão e doenças coronarianas têm tido efeitos importantes para aumentar os níveis de adiponectina e, simultaneamente, diminuir a resistência à insulina e a disfunção endotelial. .