ASPECTOS GERAIS E ABORDAGEM TERAPÊUTICA DA QUERCETINA SOBRE AS COMPLICAÇÕES DO DIABETES CAUSADAS PELO ESTRESSE OXIDATIVO

Os flavonides pertencem classe de compostos fenlicos, que diferem entre si pela sua estrutura qumica e caractersticas particulares. Frutas, vegetais, gros, flores, ch e vinho so exemplos de fontes destes compostos. A quercetina o principal flavonide presente na dieta humana, sendo a representante mais caracterstica da subclasse flavonol da famlia dos flavonides. Desde a sua descoberta, os estudos publicados na literatura cientfica apontam para o seu papel crucial no combate ao estresse oxidativo, associado a diversas condies patolgicas. No diabetes mellitus (DM), por exemplo, tambm tem sido relatada sua eficincia na inibio da enzima aldose redutase que participa da via dos poliis. Nesta contextualizao e considerando as graves consequncias advindas do DM para a sade e qualidade de vida, props-se neste trabalho uma reviso geral da literatura pertinente, a fim de reunir dados sobre aspectos biolgicos e funcionais da quercetina, bem como, sua atuao benfica nas complicaes do diabetes causadas pelo estresse oxidativo

Combination vitamin C and vitamin E prevents enteric diabetic neuropathy in the small intestine in rats

The present study evaluated the effects of supplementation with a combination of vitamin C and vitamin E on NADH-diaphorase-positive (NADH-d+) and neuronal nitric oxide synthase (nNOS)-immunoreactive myenteric neurons in the duodenum and ileum in diabetic rats. Forty rats were distributed into the following groups: normoglycemic (N), normoglycemic supplemented with vitamin C and vitamin E (NS), diabetic (D), and diabetic supplemented with vitamin C and vitamin E (DS). Vitamin C was added to the drinking water, and vitamin E was incorporated in the diet (1%). After 120 days, the animals were euthanized, and the duodenum and ileum were subjected to NADH-d and nNOS staining. Quantitative and morphometric analyses of myenteric neurons were performed. Diabetes reduced NADH-d+ neurons in the D group. The density of nitrergic neurons was not changed by diabetes or vitamin treatment. Hypertrophy of the cell body area of NADH-d+ and nNOS-immunoreactive neurons was observed in both intestinal segments. Combined supplementation with vitamin C and vitamin E prevented the reduction of the density of NADH-d+ neurons and hypertrophy, demonstratred by both techniques. Supplementation with a combination of vitamin C and vitamin E promoted myenteric neuroprotection in the small intestine in diabetic rats

Age-related changes in myosin-V myenteric neurons, CGRP and VIP immunoreactivity in the ileum of rats supplemented with ascorbic acid

We examined the effects of ascorbic acid supplementation on myosin-V, calcitonin gene-related peptide (CGRP) and vasoactive intestinal polypeptide (VIP) immunoractivities in the myenteric neurons in aging rats. Male rats were divided into groups: young 90-day-old rats (E90), 345-day-old control rats (E345), 428-day-old control rats (E428), 90- to 345-day-old rats treated with ascorbic acid (1 g/L) (EA345), and 90- to 428-day-old rats treated with ascorbic acid (1g/L) (EA428). The quantitative results showed that aging reduced the number of myosin-V-immunoreactive neurons compared with young animals (E90). Ascorbic acid supplementation in the EA345 and EA428 groups increased the average area of myosin-V neurons by 24.6% and 24.1% compared with the E345 and E428 groups, respectively. When all groups were compared, we observed significant differences for the CGRP- and VIP-immunoractive varicosities of nerve fibers from myenteric neurons. Ascorbic acid supplementation had a neurotrophic effect on all neurons studied, suggesting a neuroprotective rol