RESUMO
ABSTRACT Purpose: To evaluate the effects of the experimental subcutaneous Walker-256 tumor and L-glutamine supplementation, an antioxidant, on the glomerular morphology of rats. Methods: Twenty Wistar rats were distributed into four groups (n = 5): control (C); control treated with 2% L-glutamine (CG); rats with Walker-256 tumor (WT); and rats with Walker-256 tumor treated with 2% L-glutamine (WTG). Renal histological samples were submitted to periodic acid-Schiff and Masson's Trichrome staining to analyze glomerular density, morphometry of glomerular components and glomerulosclerosis; and to immunohistochemistry for fibroblast growth factor-2 (FGF-2). Results: WT showed 50% reduction in body mass gain and cachexia index > 10%, while WTG demonstrated reduction in cachexia (p < 0.05). WT revealed reduction of glomerular density, increase in the glomerular tuft area, mesangial area, matrix in the glomerular tuft, decrease in the urinary space and synechia, and consequently higher glomerulosclerosis (p < 0.05). L-glutamine supplementation in the WTG improved glomerular density, and reduced glomerular tuft area, urinary space, mesangial area, and glomerulosclerosis compared to WT(p < 0.05). WT showed higher collagen area and FGF-2 expression compared to C (p < 0.05). WTG presented lower collagen fibers and FGF-2 expression compared to WT (p < 0.05). Conclusions: L-glutamine supplementation reduced cachexia and was beneficial for glomerular morphology of the rats, as well as it reduced kidney damage and improved the remaining glomeruli morphology.
RESUMO
Os flavonóides pertencem à classe de compostos fenólicos, que diferem entre si pela sua estrutura química e características particulares. Frutas, vegetais, grãos, flores, chá e vinho são exemplos de fontes destes compostos. A quercetina é o principal flavonóide presente na dieta humana, sendo a representante mais característica da subclasse flavonol da família dos flavonóides. Desde a sua descoberta, os estudos publicados na literatura científica apontam para o seu papel crucial no combate ao estresse oxidativo, associado a diversas condições patológicas. No diabetes mellitus (DM), por exemplo, também tem sido relatada sua eficiência na inibição da enzima aldose redutase que participa da via dos polióis. Nesta contextualização e considerando as graves consequências advindas do DM para a saúde e qualidade de vida, propôs-se neste trabalho uma revisão geral da literatura pertinente, a fim de reunir dados sobre aspectos biológicos e funcionais da quercetina, bem como, sua atuação benéfica nas complicações do diabetes causadas pelo estresse oxidativo.
Flavonoids belong to the class of phenolic compounds that differ by their chemical structure and characteristics. Fruits, vegetables, grains, flowers, tea and wine are examples of sources of these compounds. Quercetin is the major flavonoid present in the human diet and it is the most typical representative of the flavonol subclass of the flavonoid family. Since its discovery, studies published in scientific literature point to its crucial role in combating oxidative stress associated with various pathological conditions. In diabetes mellitus (DM), for example, it has been also reported the effectiveness in inhibiting aldose reductase enzyme that participates of polyol pathway. In this context and considering the dire consequences of diabetes to health and quality of life, it was proposed in this paper a general review of relevant literature in order to gather data on biological and functional aspects of quercetin and its beneficial role in the complications diabetes caused by oxidative stress.