EFEITO DO RESVERATROL NA CAPACIDADE FAGOCÍTICA E NA PRODUÇÃO DE ESPÉCIES REATIVAS DE OXIGÊNIO E NITROGÊNIO DE MACRÓFAGOS PERITONEAIS DE RATOS MACHOS E DE FÊMEAS (DIESTRO E PROESTRO)

Abstract

Resveratrol is a phytoalexin found in several plants, like grapes (Vitis vinifera), synthesized in response to injury, attack by fungior, mechanical action and also by ultraviolet radiation Currently this bioactive compound has been the subject of interesting research, due to some properties that have already been assigned such as antioxidant and phytoestrogen. Its antioxidant activity is wellknown and is conferred by its ability to capture free radicals produced by cells or to interfere with signaling pathways of free radical production and detoxification. Furthermore, it is known that resveratrol exhibits characteristics of phytoestrogens, being molecularly similar to oestrogen. The intake of bioactive compounds in the diet is important because they exert effects on immune responses. Macrophages are cells in our immune system that are constituents of the mononuclear phagocytic system, which is our first line of defense against infectious agents. Several authors have reported that these cells express receptors for oestrogen hormones, and are regulated by these. So this study aimed to investigate the effect of resveratrol on the functionality of rat´s peritoneal macrophages, making a comparative study between males and females. Macrophages were obtained median laparotomy from the peritoneal cavity of Wistar rats divided into 3 groups (males, females in diestrus and proestrus females). Macrophages in culture medium RPMI 1640 supplemented with fetal calf serum (10%) were seeded in culture plates and incubated in an incubator with humid atmosphere of 5% CO2 for 2 hours. After complete adhesion, the cells were treated for a period of 24 hours with 5 and 10 M resveratrol, quercetin 5 and 10M (control of antioxidant activity) and 17-estradiol 0.01M and 10M (control of estrogenic activity). Afterwards the production of reactive oxygen and nitrogen were evaluated as well as the phagocytic capacity of macrophages treated. Resveratrol 10M significantly inhibited the: production of nitric oxide (NO) measured using the Griess reagent and production hydrogen peroxide (H2O2) determined by use of reagent xylenol orange. However the resveratrol didn’t change the phagocytic capacity under opsonized and nonopsonized particles assessed by optical microscopy. The inhibition of NO and H2O2 production by resveratrol was homogeneous among the groups. This inhibitory effect on NO production and H2O2 was also observed for quercetin.The treatment with 17-estradiol reduced production of NO and H2O2 induced by LPS only for macrophages in rats males. The immunosuppressive effects of resveratrol corroborate the described anti-inflammatory and antioxidant potential of this phenolic compound. Resveratrol in this study, compared to 17-estradiol and quercetin, shown to have antioxidant effects stronger than phytoestrogens. It was observed yet that its effect may vary between groups, and males and females in diestrus respond similarly to treatment with resveratrol and females in proestrus, the answer is different, thereby displaying a pre-modulation by 17-estradiol which these groups were exposed. However, in future, these results will need to be confirmed.