Diseases such as atherosclerosis, arthritis and cancer have been related with imbalance in ROS production and failures in regulation of the MMPs. Authors suggested a relationship between MPP activity and ROS. Our research group has demonstrated that retinol 7 microM induced changes in Sertoli cell metabolism linking retinol treatment and oxidative stress. We verified MMP activity in Sertoli cells treated with vitamin A using gelatin zymography. We found that retinol (7 microM) and retinoic acid (1 nM) induced MMP-2 activity in Sertoli cells. Antioxidants reversed retinol-induced but not retinoic acid-induced MMP-2 activity. Moreover, retinol but not retinoic acid increased ROS production quantified by DCFH-DA oxidation. We found that retinol and retinoic acid induced ERK1/2 phosphorylation, but only retinol-increased MMP-2 activity was inhibited by UO126, an ERK1/2 phosphorylation inhibitor. Our findings suggested that retinol-induced MMP-2 activity, but not retinoic acid-induced MMP-2 activity, was related to ERK1/2 phosphorylation and ROS production.

Dehydroepiandrosterone (DHEA) is an endogenous steroid hormone involved in a number of biological actions. This study shows the effects of DHEA on glucose metabolism, hydrogen peroxide and thioredoxin levels in the skeletal muscle of control and diabetic rats. Control and diabetic rats were chronically treated with DHEA (10mg/kg) diluted in oil. Plasma concentration of DHEA and glucose, glucose uptake and oxidation, hydrogen peroxide, GLUT4, Akt and thioredoxin (Trx) was measured in the muscle. Results showed that there was a decrease in blood glucose in diabetic rats, probably linked to an increase in the glucose oxidation by the muscle or glucose uptake by some tissues. Despite the increase in the expression of GLUT4 in DHEA-treated rats, the glucose uptake was only higher in the control rats, showing that the glucose transporter may be present but not functional in the diabetic rats. The low expression of Trx due to diabetes became even lower with DHEA treatment. Although the reduction in blood glucose may be favorable, the decrease in Akt and Trx displays an environment conducive to redox imbalance. Thus, further studies are needed to ascertain the effects of DHEA treatment in diabetic rats.

RESUMODescreve-se um caso de eritrocitose absoluta (hematócrito: 74%, hemoglobina: 24,2g/dl) em um cão com tumor venéreo transmissível cutâneo.

Cardiovascular disease (CVD) accounts for up to 80 % of the mortality in persons with type 2 diabetes, with the age-adjusted relative risk of death due to CVD being 2 to 4 times higher than in the general population. There is considerable evidence that a diet enriched with n-3 fatty acids, specifically eicosapentaenoic acid (EPA, 20 :5 n-3) and docosahexaenoic acid (DHA, 22 :6 n-3), protects against antiinflammatory process, atherosclerotic heart disease, myocardial infarction and sudden death. The aim of the study is to estimate and compare the mean daily intake of EPA and DHA polyunsaturated fatty acids in type 2 diabetic patients and nondiabetic subjects. The mean daily intakes of EPA and DHA were also compared with several dietary recommendations to prevent cardiovascular diseases. The study was performed in 150 Portuguese type 2 diabetic patients and 143 nondiabetic subjects. The study population was divided into three groups: group I-75 diabetics with angiopathy; group II-75 diabetics without angiopathy and group III-143 nondiabetic subjects. The statistical analysis was performed by one-way analysis of variance and Scheffe test. Nutrients intake were estimated from a foodfrequency questionnaire previously validated for Portuguese adults with cardiovascular disease by the Epidemiology Department, Faculty of Medicine, University of Oporto. Group III had a lower mean EPA daily intake (96 mg/day) compared to the mean values obtained for groups I (115 mg/day) and II (114 mg/day). For DHA, groups I and II had the same mean daily intake (260 mg/day), which was higher than the mean value estimated for group III (216 mg/day). Statistical differences were achieved for EPA and DHA daily intakes between diabetic patients and nondiabetic patients. According to the recommendations of the French Food Safety Agency, American Dietetic Association and the International Society for the Study of Fatty Acids and Lipids, to prevent cardiovascular diseases, the sum of EPA + DHA daily intake should provide 500 mg/day. All groups in the study had a mean daily intake significantly different than the recommended value, but the prevalence of subjects with daily intakes lower than the recommended values was for each group, respectively: group I-75 %, group II-79 % and group III-93 %. As recommended by the French Food Safety Agency, the mean daily intakes of DHA for all study groups were higher than 120 mg/day. The daily intake of EPA and DHA is similar between diabetics with and without angiopathy, but higher in diabetics compared to nondiabetic subjects. These results suggest that diabetic patients are more concern with the diet than nondiabetic subjects. The prevalence of EPA and DHA daily intake below the recommended values is very high in the study population. This fact is associated with a higher risk to develop cardiovascular disease and with a lower ability to protect against inflammatory process in diabetes.