Table of Contents Author Guidelines Submit a Manuscript
Evidence-Based Complementary and Alternative Medicine
Volume 2011, Article ID 248592, 12 pages
http://dx.doi.org/10.1155/2011/248592
Research Article

Suppressive Effect on Lipopolysaccharide-Induced Proinflammatory Mediators by Citrus aurantium L. in Macrophage RAW 264.7 Cells via NF- B Signal Pathway

1Institute of Life Science and College of Veterinary Medicine, Gyeongsang National University, Gazwa, Jinju 660-701, Republic of Korea
2Department of Internal Medicine, Institute of Health Sciences, Gyeongsang National University School of Medicine and Gyeongnam Regional Cancer Center, Gyeongsang National University Hospital, Jinju 660-702, Republic of Korea
3Food Technology, Institute of Agriculture & Life Science, Gyeongsang National University, Jinju 660-701, Republic of Korea
4Division of Applied Life Sciences (BK21 program), Graduate School and Institute of Agriculture & Life Science, Gyeongsang National University, Jinju 660-701, Republic of Korea
5Korea National Animal Research Resource Center and Korea National Animal BioResource Bank, Gyeongsang National University, Jinju 660-701, Republic of Korea

Received 2 March 2010; Revised 19 April 2010; Accepted 20 July 2010

Copyright © 2011 Sang-Rim Kang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Citrus fruits have been used as an edible fruit and a traditional medicine since ancient times. In particular, the peels of immature citrus fruits are used widely in traditional herbal medicine in Korea, as they are believed to contain bioactive components exerting anti-inflammatory activity. This study examined whether the crude methanol extract of Citrus aurantium L. (CME) has a suppressive effect on inducible enzymes and proinflammatory cytokines by inhibiting the NF- B pathway in LPS-stimulated macrophage RAW 264.7 cells. The cells were pretreated with the indicated concentrations of CME (5, 10, 20, and 50  g/mL) and then treated with LPS (1  g/mL). The results showed that CME (10, 20, and 50  g/mL) inhibited the LPS- (1  g/mL) induced mRNA and protein expression of iNOS in macrophage Raw 264.7 cells. In addition, the expression of COX-2 was inhibited at the mRNA and protein levels by CME in a dose-dependent manner. The mRNA expression of proinflammatory cytokines, such as TNF- and IL-6, were markedly reduced by CME (10, 20, and 50  g/mL). Moreover, CME clearly suppressed the nuclear translocation of the NF- B p65 subunits, which was correlated with its inhibitory effect on I- B phosphorylation. These results suggest that CME has anti-inflammatory properties by modulating the expression of COX-2, iNOS, and proinflammatory cytokines, such as TNF- and IL-6, in macrophage RAW 264.7 cells via the NF- B pathway.