A HIPERGLICEMIA E OS MECANISMOS ENVOLVIDOS NAS DISFUNÇÕES VASCULARES DO DIABETES MELLITUS

O Diabetes Mellitus (DM) é uma síndrome de etiologia múltipla, decorrente da falta de insulina e/ou da incapacidade de a insulina exercer adequadamente seus efeitos. Caracteriza-se por hiperglicemia crônica, com distúrbios do metabolismo dos carboidratos, lipídios e proteínas. Constitui-se um importante problema de saúde pública, devido à sua elevada prevalência, ao desenvolvimento de complicações crônicas incapacitantes e ao alto custo econômico gerado pelo seu tratamento. A hiperglicemia é um dos fatores mais importantes para o aparecimento e progressão das complicações vasculares do DM. A elevação persistente nas concentrações da glicose provoca mudanças na estrutura e na função de proteínas plasmáticas e tissulares, com efeitos indesejáveis sobre a saúde do portador de diabetes. O aumento da via dos polióis, glicosilação não-enzimática, com a produção dos produtos finais da glicação avançada (AGEs); estresse oxidativo, gerando o aumento de radicais livres e alteração da proteína kinase C, levando à disfunção endotelial e à aterogênese, são alguns dos mecanismos que tentam explicar o dano vascular induzido pela hiperglicemia. O objetivo desta revisão bibliográfica é discutir os mecanismos pelos quais a hiperglicemia pode desencadear as disfunções vasculares associadas com o DM

<b>Testis morphophysiology of rats treated with nandrolone decanoate and submitted to physical training</b> - doi: 10.4025/actascihealthsci.v35i2.16406

The mammalian testis is a complex organ with endocrine and exocrine functions. It consists of seminiferous tubules where the production of the male gametes called spermatogenesis occurs. This process is influenced by a number of factors including the use of physical performance-enhancing drugs. The objective of this study was to evaluate the effects of the anabolic steroid nandrolone decanoate on the morphofunctional structure of testes in sedentary rats and rats subjected to moderate aerobic exercise training. Twenty-four male rats were divided into four experimental groups: sedentary control, sedentary treated, trained control and trained treated.The training lasted eight weeks and consisted of running on a programmable ergometer treadmill, tailored to train eight rats simultaneously. Treated animals received intramuscular injections of nandrolone decanoate (0.5 mg kg-1 body weight) during the last four weeks of physical training, while the control groups received intramuscular injections of vehicle (vegetable oil).The male reproductive system morphology showed that treatment with nandrolone decanoate, in both sedentary and trained rats, promoted morphological and functional changes that result in reduced efficiency of spermatogenesis

Evaluation of the potential use of rebaudioside-A as sweetener for diet jam

Sweeteners based on stevia extract contain a series of diterpene glycosides derivatives from steviol, standing out the rebaudioside-A. There is no tabletop sweeteners in the market formulated purely with rebaudioside-A yet, so its use in foods depends on the development of new products followed by physicochemical and sensory evaluations. This work presents the formulation of a diet strawberry jam dyed with cranberry juice and sweetened with rebaudioside-A purified from stevia plants of the lineage UEM-320 developed in the Centro de Estudos de Produtos Naturais da Universidade Estadual de Maringá. Evaluations of physicochemical properties, microbiological and sensory characteristics were carried out for the product in comparison with a control sweetened with equal amount of sucralose. The results showed that the physicochemical characteristics of the sample and the control are not significantly different and the supplementation with cranberry juice increased both color and total phenolic content in both samples. The sensory acceptability indicated a significant preference for the formulation sweetened with 100% of rebaudioside-A, only in the items flavor and purchase intent. We concluded that rebaudioside-A has a better sensory performance than sucralose, even this last one being 1.33 fold sweeter than rebaudioside-A

Stevia Nonsweetener Fraction Displays an Insulinotropic Effect Involving Neurotransmission in Pancreatic Islets

Stevia rebaudiana (Bert.) Bertoni besides being a source of noncaloric sweeteners is also an important source of bioactive molecules. Many plant extracts, mostly obtained with ethyl acetate solvent, are rich in polyphenol compounds that present insulinotropic effects. To investigate whether the nonsweetener fraction, which is rich in phenolic compounds isolated from Stevia rebaudiana with the solvent ethyl acetate (EAF), has an insulinotropic effect, including interference at the terminals of the autonomic nervous system of the pancreatic islets of rats. Pancreatic islets were isolated from Wistar rats and incubated with EAF and inhibitory or stimulatory substances of insulin secretion, including cholinergic and adrenergic agonists and antagonists. EAF potentiates glucose-stimulated insulin secretion (GSIS) only in the presence of high glucose and calcium-dependent concentrations. EAF increased muscarinic insulinotropic effects in pancreatic islets, interfering with the muscarinic receptor subfamily M3. Adrenergic inhibitory effects on GSIS were attenuated in the presence of EAF, which interfered with the adrenergic α2 receptor. Results suggest that EAF isolated from stevia leaves is a potential therapy for treating type 2 diabetes mellitus by stimulating insulin secretion only in high glucose concentrations, enhancing parasympathetic signal transduction and inhibiting sympathetic signal transduction in beta cells