Background
Curcuma longa has been used as spices, food preservative, coloring material, and traditional medicine. This plant also has long been used for a variety of diseases including dyslipidemia, stomach disorders, arthritis, and hepatic diseases. The
Conclusion
CLE showed anti-neuroinflammatory effects against LPS-induced microglial cells activation through the inhibition of production and expression of pro-inflammatory mediators by negative regulation of the NF-κB and MAPK signaling pathways. These anti-neuroinflammatory effects of CLE were mediated by HO-1/Nrf2 signaling pathway. Taken together, the present study suggests a potent effect of CLE to prevent neuroinflammatory diseases. It is necessary to perform additional efficacy evaluation through in vivo experiments.
Methods
Griess reaction was employed to measure the production of nitric oxide (NO), and the levels of prostaglandin E2 (PGE2) and pro-inflammatory cytokines such as interleukin 1-beta (IL-1β), IL-6 and tumor necrosis factor-α (TNF-α) were determined by using profit ELISA kits. Western blotting was used to determine the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor kappa B (NF-κB), mitogen activated protein kinases (MAPKs), heme oxygenase-1 (HO-1) and nuclear factor erythroid-2-related factor 2 (Nrf2).
Results
Pre-treatment with CLE inhibited the overproduction and overexpression of pro-inflammatory mediators including NO, PGE2, iNOS, COX-2, and pro-inflammatory cytokines such as IL-1β, IL-6 and TNF-α in LPS-induced BV2 cells. In addition, CLE suppressed the activation of the NF-κB and three MAPK signaling pathways. Treatment with CLE induced HO-1 protein expression by activating Nrf2 pathway, and inhibiting the HO-1 expression reversed the anti-inflammatory effect of CLE.