Efeitos imunomodulatórios do tratamento “in vitro” com o ácido copálico e o óxido baccharis sobre culturas de células primárias de camundongo C57BL/6

Abstract

INTRODUCTION: The immune system has essential functions to maintain the homeostasis in the body. When this system does not work properly, inappropriate immune responses can occur and, consequently, the appearance of diseases. The immune response can be modulated by using traditional drugs, such as non-steroidal and steroidal anti-inflammatory, immunosuppressive and immunomodulatory drugs. However, these are associated with high costs of treatment and the occurrence of adverse effects, sometimes serious. In this scenario, substances from natural products could be an alternative, given their cheap way of obtaining, proven efficacy and safety, in most of the times. The extract of species of the genus Baccharis and the oil-resin from copaibas have anti-inflammatory effects, as described in the literature, and the ellucidation of which substances alone present this effect could allow the development of new medication in the future. OBJECTIVE: To evaluate the in vitro immunomodulatory effects of copalic acid (CA) and baccharis oxide (BO) on cells obtained from C57BL/6 mice. MATERIAL AND METHODS: CA and BO, previously isolated, had their cytotoxicity evaluated in the MTT and blue Trypan assays. After verifying cellular viability, CA and BO were tested under different concentrations into peritoneal cells culture stimulated with lipopolysaccharide to evaluate nitric oxide (NO) production and the production of the cytokines IL-1β, IL-6, IL-12, IFN-, TNF-α; and into splenocytes culture stimulated with concanavalin A to evaluate cellular proliferation. RESULTS: In the MTT cellular viability assay, it was not observed toxicity in CA neither in BO in the concentrations of 100, 75, 50, 25 10 and 5 μM after 24 and 48 hours of exposure of the peritoneal cells to the substances. In the blue Tripan assay, realized at the times 24 and 48 hours both substances were safe at the dosage of 50 and 75 μM showing, therefore, toxicity at 100 μM. In the proliferation assay, CA presented innibitory activity against splenocytes in the concentration of 75 e 50 µM. In the nitrite assay, only CA in the concentration of 75 µM was able to reduze production of NO from peritoneal cells. In the determination of cytokines by ELISA in the stimulated and treated peritoneal cells, the CA was able to reduce the production of IL1β and IL-6 in the concentration of 75 μM, IL-12 in the concentrations of 50 and 75 μM, but presented no effect against IFN-γ e TNF-α, compared to control group. BO didn’t reduced the production of any of the cytokines. CONCLUSION: AC presented potential 9 immunomodulatory activity and it’s very likely to be one of the compounds in the copaiba oil responsabile for its anti-inflamatory effect. BO didn’t presente potential antiinflammatory activity and it’s very likely it doesn’t contribute to such activity of the extact. However, further studies must be carried out to understand into its clear mechanism of action.