Avaliação do uso de flavonoides no tratamento da inflamação / Evaluación del uso del flavonoides en el tratamiento de la inflamación / Evaluation of the flavonoides use in the treatment of the inflammation

A inflamação é considerada uma forma de defesa do nosso organismo, podendo ser desencadeada por vários estímulos. Entretanto, em determinadas situações a resposta pode ser exacerbada e contínua, tornando‒se prejudicial. Os fármacos utilizados atualmente no tratamento dos processos inflamatórios possuem efeitos adversos, sendo os compostos vegetais uma alternativa ao uso destes medicamentos. Um destes compostos são os flavonoides, que apresentam uma série de propriedades farmacológicas, destacando-se a atividade anti-inflamatória. Para a execução deste trabalho foi realizada uma pesquisa nas bases de dados do Google Acadêmico, Scientific Electronic Library Online (SciELO) e Biblioteca Virtual em Saúde (BVS), o recorte temporal usado na pesquisa compreende os anos de 2008 a 2014 e as palavras‒chave utilizadas foram flavonoides, inflamação, flavonoides na inflamação, mediadores inflamatórios e atividade dos flavonoides. Objetiva‒se apresentar diferentes estudos que avaliam a atividade dos flavonoides na inflamação, enfatizando sua ação em mediadores químicos específicos como as citocinas, óxido nítrico e metabólitos do ácido araquidônico. Observa‒se a capacidade dos flavonoides de modular estas substâncias químicas. Quercetina, miricitrina, apigenina, epicatequina, entre outros flavonoides regulam a atividade de enzimas e a síntese de mediadores químicos, responsáveis pela ativação e perpetuação do processo inflamatório, sendo esta a principal maneira com que combatem esta doença(AU)

Inflammation is considered a form of defense of our body and can be triggered by various stimuli. However, in certain situations the answer may be exacerbated and further, becoming harmful. The drugs currently used to treat inflammatory processes have adverse effects, vegetables compounds as an alternative to the use of these drugs. One of these compounds are flavonoids, which exhibit a number of pharmacological properties, especially the anti-inflammatory activity. For the execution of this study a survey was conducted in the databases Google Scholar, Scientific Electronic Library Online (SciELO) and Virtual Health Library (VHL), the time frame used in the research comprises the years 2008-2014 and the keywords used were flavonoids, inflammation, flavonoids in inflammation, inflammatory mediators and activity of flavonoids. The objective was to present different studies evaluating the activity of flavonoids in inflammation, emphasizing its action on specific chemical mediators such as cytokines, nitric oxide and arachidonic acid metabolites. The paper underlined the ability of flavonoids to modulate these chemicals. Quercetin, miricitrin, apigenin, epicatechin, and other flavonoids regulate the activity of enzymes and the synthesis of chemical mediators responsible for the activation and perpetuation of the inflammatory process, which is the main way to fight this disease(AU)

La inflamación es considerada como una defensa del organismo que se activa por diferentes estímulos; em ocasiones puede exacerbarse y causar daño. Los medicamentos actualmente usadas para tratar los procesos inflamatorios presentan efectos adversos, por lo que como una alternativa de uso se pudieran explorar algunas plantas consideradas verduras. Los flavonoides exhiben actividad antiinflamatoria entre otras propiedades farmacológicas. Para la ejecución de este estudio se revisaron las bases de datos de Google Académico, la Biblioteca Electrónica Científica en línea (SciELO) y la Biblioteca de Virtual Salud (BVS), la investigación comprende los años 2008 al 2014 y las palabras clave utilizadas fueron flavonoides, inflamación, flavonoides en la inflamación, mediadores inflamatorios y actividad de flavonoides. El objetivo era localizar estudios que evaluaran la actividad de lós flavonoides en la inflamación, con énfasis en su acción como mediadores químicos específicos como la citocinas, el óxido nítrico y metabolitos del ácido araquidónico. Se resalta la habilidad de lós flavonoides de modular estos químicos. Quercetina, miricitrina, apigenina, epicatequina entre otros flavonoides regulan la actividad de enzimas y la síntesis de mediadores químicos responsable para la activación y perpetuación del proceso inflamatorio que es la manera principal de luchar esta enfermedad(AU).

Kinetics of enzymatic modification of quercetin with cysteine by horseradish peroxidase.

The kinetic mechanism of enzymatic modification of flavonol quercetin with L-cysteine by horseradish peroxidase (HRP) was studied. Reaction of modification of quercetin was followed by recording spectral changes over time at 380 nm. All reactions were performed in 100 mM phosphate buffer pH, 6.0 at 20ºC. Kinetic parameters were determined from graphics of linear Michaelis-Menten equation. The values obtained at specified intervals were: Vmax = 0.17 ÷ 0.91 ΔA380/min, Km = 0.023 ÷ 0.5 mM, kcat = 0.21 ÷ 1.14 ΔA380/min∙nM-1 and Vmax/Km = 0.83 ÷ 26.55 ΔA380/min∙mM-1. It was found that all investigated reactions of the modification of quercetin with L-cysteine by HRP followed an ordered mechanism. We propose that HRP initially reacts with H2O2 than with quercetin and finally with L-cysteine, leading to the introduction of L-cysteine in the structure of quercetin.

Pharmacological evaluation of hyperin for antihyperglycemic activity and effect on lipid profile in diabetic rats.

Antihyperglycemic potential of hyperin at 25 and 50 mg/kg doses for 30 days to streptozotocin induced diabetic rats has been reported. In oral glucose tolerance test, hyperin treated rats showed a significant reduction in blood glucose level after 120 min. It was found that hyperin exhibited dose dependent and significant antihyperglycemic activity in streptozotocin induced diabetic rats which were nearly similar with standard drug glybenclamide. Activities of glucose-6-phosphatase, fructose-1,6-bisphosphatase, glycogen phosphorylase, glycosylated haemoglobin and level of serum urea and creatinine were significantly decreased in hyperin supplemented diabetic rats, dose dependently. Activities of hexokinase and glycogen synthase were increased with augmentation in liver glycogen, insulin and haemoglobin content in hyperin treated diabetic rats. General hematological parameters did not show any significant change in hyperin treated diabetic rats hence it is safe at these doses. Histopathological studies showed significant morphological changes in pancreatic β-cells of streptozotocin induced diabetic rats. A decreased number of secretory granules of β- cells were observed in diabetic rats and these pathological abnormalities were normalized after treatment with hyperin and standard drug glybenclamide. Further, hyperin decreases significant in serum total cholesterol, triglyceride, low density lipoprotein, very low density lipoprotein levels coupled with elevation of high density lipoprotein in diabetic rats. These results suggest that hyperin has a pivotal role in blood glucose level in streptozotocin induced hyperglycemia by improving the function of pancreatic islets and increasing glycolysis and decreasing gluconeogenesis.