Synergistic Anti-Inflammatory Effects of Ethanol Extracts from Chrysanthemum zawadskii Flower and Cudrania tricuspidata Fruit Occur via Inhibition of the NF-κB Signaling Pathway.

Chrysanthemum zawadskii (CZ) and Cudrania tricuspidata (CT) are both traditional Korea herbal medicines, which is widely used to treat fever, cough, gastritis, and women's diseases that may be linked to inflammatory response. Although it has been used to treat diseases related to inflammation, there has been no case of the synergistic anti-inflammatory properties of both extracts. Our data revealed that ethanol extracts of dried whole CZ exhibited free radical-scavenging capacity in vitro, reduced LPS-induced intracellular reactive oxygen species, and decreased the LPS-induced upregulations of the mRNAs encoding iNOS, COX-2, and IL-6 in RAW 264.7 cells, without significant cytotoxicity. This anti-inflammatory effect was most evident from flower extracts: ethanol extracts from flowers significantly reduced the LPS-induced upregulations of iNOS and COX-2 at a concentration of 100 µg/ml. An ethanol extract of the fruit from CT also exerted a radical scavenging capacity and suppressed LPS-induced proinflammatory gene expression: 5.5 µg/ml of the ethanol extract significantly reduced the ability of LPS to induce the mRNA expression levels of iNOS and IL-6 without apparent cytotoxicity. Furthermore, as little as 1.0 µg/ml of the combined ethanol extracts of CZ flower and CT fruit reduced the LPS-induced changes monitored herein, decreasing the upregulations of iNOS and IL-6, and decreasing the nuclear localization of NF-κB p65. These results suggest that the observed synergistic anti-inflammatory effects may be mediated via inhibition of NF-κB signaling. Taken together, these data suggest that ethanol extracts from CZ flowers and CT fruits have synergistic anti-inflammatory effects and that a combination of the two extracts could prove useful for the treatment of inflammation-related diseases.