Studying anti-inflammatory action of Cordia myxa fruit extract on induced chronic stress model in male rats and expected improvement in depression treatment in humans

Abstract

Depression is one of the most common phsychiatric diseases that treated with variety of medications that have significant problems to human health and increased suicide rates. Herbal medications have recently gained a lot of interest in the treatment of depression due to their safety, efficacy, and cost-effectiveness, so this study was aimed to evaluate effects of C.Myxa fruit extract on the model of chronic unpredictable stress (CUS) and the proinflammatory cytokine IL-6 in male rat’s brains. Therefore, sixty male rats were divided into six groups. Group1 (control) was neither exposed to CUMS nor received any treatment while group 2 was exposed to CUMS for 24 days with normal saline treatment for 14 days, group 3 was exposed to CUMS for 24 days and received 10 mg/kg fluoxetine daily on day 10 for 14 days, and group 4, 5 and 6 were exposed to CUMS for 24 days and received C.Myxa extract (125,250 and 500 mg/kg respectively) on day 10 for 14 days. The antidepressant effect of fluoxetine and C.Myxa extract were evaluated by using sucrose preference test and open field test. At the end of the experiments, animals were sacrificed by decapitation, and interleukin 6 level determined by enzyme linked immunosorbent assays kit (Elisa) in rat’s brain tissues. in groups 3, 4, 5 and 6, the means of sucrose preference index (SPI) on day10 significantly decreased (P-value <0.05) as compared with day 0, while the means of SPI on day 25 of groups 3,4,5 and 6 significantly increased (P-value <0.05) as compared with day10. In group 2, the mean of SPI significantly decreased (P-value <0.05) as compared with group 1, while in groups 3, 4, 5, and 6 the means of SPI significantly increased (P-value <0.05) as compared with group 2 on day 25. Open field test (OFT) showed that in groups 2, 3, 4, 5 and 6, the means of Rearing frequencies on day10 significantly decreased (P-value <0.05) as compared with day 0, while the means of  Rearing frequencies on day 25 of groups 3,4,5 and 6 significantly increased (P-value <0.05) as compared with day10. In group 2, the mean of Rearing frequencies significantly decreased (P-value <0.05) as compared with group 1, while in groups 3, 4, 5, and 6 the means of Rearing frequencies, significantly increased (P-value <0.05) as compared with group 2 on day 25’

In terms of the Interleukin-6 levels, The means of the IL-6 concentrations in brain tissue of group 2 significantly increased (P-value <0.05) as compared with group1, while in groups 3, 4, 5, and 6 the means of the IL-6 concentrations in brain tissue significantly decreased (P-value <0.05) as compared with group 2. In conclusion, C. Myxa has an antidepressant-like activity and reversed the stress-induced IL-6 higher levels