Anti-inflammatory effect of anemarsaponin B isolated from the rhizomes of Anemarrhena asphodeloides in LPS-induced RAW 264.7 macrophages is mediated by negative regulation of the nuclear factor-kappaB and p38 pathways.
Anemarrhena asphodeloides is widely used in traditional Chinese medicine, and is known to have anti-diabetic and diuretic effects. In this study, we evaluated the anti-inflammatory effects of anemarsaponin B (ASB), a steroidal saponin isolated from the rhizomes of A. asphodeloides (Liliaceae), in LPS-stimulated RAW 264.7 macrophage cell line. ASB significantly and dose-dependently decreased the protein and mRNA levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). ASB also reduced the expressions and productions of pro-inflammatory cytokines, including those of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6). Electrophoretic mobility shift assay (EMSA) and reporter gene assays revealed that ASB attenuated the LPS-induced DNA binding and transcriptional activity of nuclear factor-kappa B (NF-kappaB). In addition, it was found that pretreatment with ASB significantly inhibited the nuclear translocation of the p65 subunit of NF-kappaB by blocking the phosphorylation of inhibitory kappa B-alpha (IkappaB-alpha). On the other hand, ASB inhibited the phosphorylation of MAP kinase kinases 3/6 (MKK3/6) and mixed lineage kinase 3 (MLK3), which are both involved in the p38 pathway. Taken together, these results suggest that anti-inflammatory effect of ASB in LPS-treated RAW 264.7 macrophages is associated with the inhibition of NF-kappaB transcriptional activity, possibly via the p38 MAP kinase pathway.
Department of Pharmaceutical Biochemistry, College of Pharmacy, Kyung-Hee University, Dongdaemun-Ku, Hoegi-Dong, Seoul 130-701, South Korea.
Ji-Yeon
JY
Kim
Ji-Sun
JS
Shin
Jong Hoon
JH
Ryu
Sun Yeou
SY
Kim
Young-Wuk
YW
Cho
Jung-Hye
JH
Choi
Kyung-Tae
KT
Lee
D031403:Anemarrhena / Q000737:chemistry*; D000894:Anti-Inflammatory Agents, Non-Steroidal; D015153:Blotting, Western; D002460:Cell Line; D051546:Cyclooxygenase 2 / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D015850:Interleukin-6 / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects*; D016328:NF-kappa B / Q000096:biosynthesis*; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D018517:Plant Roots / Q000737:chemistry; D012313:RNA / Q000096:biosynthesis / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012503:Saponins / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013778:Tetrazolium Salts; D013844:Thiazoles; D014315:Triterpenes / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000096:biosynthesis*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D015850:Interleukin-6; D008070:Lipopolysaccharides; D016328:NF-kappa B; D012503:Saponins; D013778:Tetrazolium Salts; D013844:Thiazoles; D014315:Triterpenes; D014409:Tumor Necrosis Factor-alpha; C073427:anemarsaponin B; D009569:Nitric Oxide; D012313:RNA; D052247:Nitric Oxide Synthase Type II; D051546:Cyclooxygenase 2; D048051:p38 Mitogen-Activated Protein Kinases; C022616:thiazolyl blue; D015232:Dinoprostone