Lupalbigenin Inhibiting NF-κB Translocation Associated with Anti-Inflammatory Responses in Lipopolysaccharide Stimulated RAW 264.7 Macrophages

Abstract

Background: The dried stem of Derris scandens Benth. is well known as an Asian medicinal plant and is used for a variety of ailments. It is claimed to used for the relief of muscle aches and pain and revealed the presence of compounds that appear to modify inflammatory processes. Chemical analysis of D. scandens have revealed the presence of numerous isoflavone derivatives. Lupalbigenin, prenylated isoflavone is a key component of D. scandens stem ethanolic extract. Its anti-inflammatory activity in cell culture had never previously been reported which is why this study was performed. Objective: To investigate the inflammatory activity through molecular signaling pathways of lupalbigenin from D. scandens aqueous ethanol extract using LPS-induced cell changed in Raw 264.7 macrophages cells. Materials and Methods: Lupalbigenin was purified from aqueous extract of dried stem of D. scandens. Cell viability of lupalbigenin in Raw 264.7 cell was determined by MTT assay. Griess reagent has been used for nitric oxide determination. The protein expression of iNOS, cyclooxygenase-2 (COX-2), TNF-α, NF-κB and MAPK were performed by Western blotting. In addition, we also used immunofluorescent assay to examine the NF-κB translocation from nucleus to cytoplasm. Results: Lupalbigenin at 1.25 and 2.5 mM effectively inhibited the LPS-induced tumor necrosis factor-alpha (TNF-α), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS) as well as nuclear factor kappa B (NF-κB). In addition, lupalbigenin prevented LPS-induced inflammation by decreasing p38 and JNK expression in mitogen-activated protein kinase (MAPK) pathway. Conclusion: Lupalbigenin at low concentrations showed down-regulation of inflammatory gene and protein expressions as well as inhibiting NF-κB translocation. Lupalbigenin could be used as an anti-inflammatory agent. © JOURNAL OF THE MEDICAL ASSOCIATION OF THAILAND