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Objectives This study examined the effect of Vitis vinifera grape skin extract (ACH09) on hyperglycaemia and the insulin-signalling cascade in alloxan-treated mice. Methods Glycaemia, serum insulin and Western blot analysis of insulin cascade proteins were evaluated in the gastrocnemius muscles of four groups of adult mice: control, ACH09 (200 mg/kg per day, p.o.), alloxan (300 mg/kg, i.p.) and alloxan + ACH09. Insulin secretion in isolated pancreatic islets was also studied. Key findings Glycaemia values in the alloxan + ACH09 and ACH09 groups were significantly lower than in the alloxan-treated and control groups, respectively. Increased insulin resistance (HOMA index) was observed in the alloxan-treated group but not in the alloxan + ACH09 group. Insulin receptor content and Akt phosphorylation were significantly greater in the alloxan + ACH09 group compared with the alloxan-treated group. The glucose transporter (GLUT-4) content was reduced in alloxan-treated mice compared with the control group, while alloxan + ACH09 and ACH09-treated mice showed a significant increase in GLUT-4 content. ACH09 treatment did not change glucose-induced insulin secretion in isolated pancreatic islets. Conclusions The results suggest that ACH09 has hypoglycaemic and antihyperglycaemic effects that are independent of an increase in insulin release but are probably dependent on an increase in insulin sensitivity resulting from an activation of the insulin-signalling cascade in skeletal muscle. [ABSTRACT FROM AUTHOR]

Obesity is one of the most serious global public health challenges of the 21st century. The aim of this study was to investigate the effects of dietary incorporation of açai seed flour (ASF) on lipid metabolism of high fat diet-induced obesity mice. C57BL/6 male mice were divided into four groups (n = 10): control group (C); high fat diet (HF); high fat diet with ASF (HFA15 and HFA30, high fat diet containing 15% or 30% ASF, respectively) for 12 weeks. Body composition, lipid metabolism and excretion, hepatic and adipose tissue morphology and biochemical parameters were assayed. The incorporation of 15% or 30% ASF in mice's diet promoted protective effect upon weight gain, prevented insulin resistance and improved lipid profile of animals, which had lower concentrations of glucose, insulin and leptin. Thus, ASF reduced lipogenesis preventing the development of fatty liver disease and hypertrophic obesity. It was also observed the influence of ASF consumption on the modulation of proteins involved with cholesterol synthesis and excretion. The high fecal weight in the ASF group demonstrates a significant action of the fibers in the excretion of bile acids and cholesterol. Biochemical parameters of the nutritional status were not altered nor were signs of toxicity observed in the animals with the ASF consumption, suggesting that the flour does not present toxic or harmful effects to the animals' health. The use of ASF prevents the development of obesity and its commorbidities, especially hepatic steatosis increasing cholesterol excretion. [ABSTRACT FROM AUTHOR]

Abstract: Short-term exposure to cigarette smoke (CS) leads to acute lung inflammation (ALI) by disturbing oxidant/antioxidant balance. Both CS exposure and lung inflammation are important risk factors in the pathogenesis of chronic obstructive pulmonary disease. Nitric oxide (NO) is an oxidant both present in CS and produced in the inflammatory response, but its role in the effects of CS exposure is unclear. Our aim was to study involvement of NO in a model of CS exposure. Groups of mice (male C57BL/6) exposed to CS (six cigarettes per day over five days) were simultaneously subjected to treatment with vehicle (CS), 60mg/kg/day ω-nitro-l-arginine methyl ester (CS+ l-NAME), 20mg/kg/day nitroglycerine (CS+NTG), or 120mg/kg/day l-arginine (CS+ l-arg). Bronchoalveolar lavage fluid was then aspirated to perform cell counts, and malondialdehyde (MDA), nitrite, catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels were measured in lung homogenates. Macrophage and neutrophil counts were increased in the CS (p <0.001) and CS+ l-NAME groups (p <0.05 and p <0.01, respectively); the CS+NTG and CS+ l-arg groups showed no differences from the control group. MDA was increased in the CS (p <0.05) and CS+ l-NAME (p <0.01) groups when compared to the control group. Nitrite levels were decreased in the CS and CS+ l-NAME groups (p <0.001) and increased in the CS+NTG (p <0.001) and CS+ l-arg (p <0.01) groups when compared to the control. CAT, SOD and GPx activities in the CS and CS+ l-NAME groups were all significantly increased compared to the control group. Our results suggest that administration of NO donors or substrates may be a useful therapy in the treatment of ALI caused by CS. [Copyright &y& Elsevier]

Background: Oxidative stress has been implicated in the pathogenesis and progression of chronic obstructive pulmonary disease (COPD), and cigarette smoke (CS) is known to be one of the major sources of oxidants in the lungs. We postulated that acute administration of GSE (grape skin extract) would either reduce or protect the ALI (acute lung inflammation) produced by CS via NO release., Material/methods: We adopted a nutritional approach by investigating the inflammatory cells, metalloproteinase 9 (MMP-9) activity, and oxidative stress markers (superoxide dismutase - SOD; catalase - CAT; glutathione peroxidase (GPx) activities and malondialdehyde - MDA - levels) that play a role in the development of acute lung inflammation (ALI). Therefore, we tested an orally active antioxidant produced from grape skin manipulation (grape skin extract - GSE), in mice exposed to CS from 6 cigarettes a day for 5 days. In addition, we used a separate group treated with NG-nitro-L-arginine methyl ester (an NO inhibitor) to confirm nitric oxide (NO) involvement in GSE effects., Results: We showed for the first time that administration of GSE inhibited ALI and oxidative damage induced by CS. This is associated with decreased MMP-9 activity, decreased number of inflammatory cells in the bronchoalveolar lavage fluid, and reduced levels of lipid peroxidation. Our results indicate that beneficial effects of GSE are NO-dependent., Conclusions: The study indicates that alteration of the oxidant-antioxidant balance is important in the pathogenesis of CS-induced ALI and suggests lung protective effects of GSE treatment in the mouse.