10-Hydroxy-2-decenoic acid from Royal jelly: A potential medicine for RA

Chemical structures of 10-hydroxy-trans-2-decenoic acid (10H2DA). Rheumatoid arthritis synovial fibroblasts (RASFs) are known to produce matrix metalloproteinases (MMPs) and cause joint destruction. The purpose of this study is to develop a potential medicine for rheumatoid arthritis (RA). To this end, first, the MMPs inhibition factor was purified from an alkali-solubilized fraction of RJ (Apis mellifera) by C18 reverse-phase column chromatography and identified as 10-hydroxy-2-decenoic acid (10H2DA) by LTQ XL analysis. Next, Experimental test 10H2DA how to inhibited the activities of MMPs: with RASFs isolated from rheumatoid tissues by enzymatic digestion, cultures in monolayers were treated with 10H2DA (0.5 mM, 1 mM, and 2 mM) or PBS for 2 h followed by stimulation with TNF-α (10 ng/ml) for 2 h, mRNA. Protein levels of MMP-1 and MMP-3 were measured by real-time PCR and enzyme-linked immunosorbent assay (ELISA), the DNA-binding activity of activator protein-1 (AP-1) and nuclear factor κB (NF-κB) by electrophoretic mobility shift assay (EMSA), and the protein kinase activity of p38, ERK and JNK by kinase assay. The molecular investigation revealed that the 10H2DA-mediated suppression was likely to occur through blocking p38 kinase and c-Jun N-terminal kinase–AP-1 signaling pathways. In contrast, 10H2DA had no effect on extracellular signal-regulated kinase activity, NF-κB DNA-binding activity and IκBα degradation. These results suggest that 10H2DA may be of potential therapeutic value in inhibiting joint destruction in RA.