Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học quốc tế cung cấp cho các bạn kiến thức về ngành y đề tài: Aciculatin inhibits lipopolysaccharide-mediated inducible nitric oxide synthase and cyclooxygenase-2 expression via suppressing NF- B and JNK/p38 MAPK activation pathways | Hsieh et al. Journal of Biomedical Science 2011 18 28 http content 18 1 28 The cost of publication in Journal of Biomedical Science Is borne by the National Science Council Taiwan JOURNAL OF BIOMEDICAL SCIENCE RESEARCH Open Access Aciculatin inhibits lipopolysaccharide-mediated inducible nitric oxide synthase and cyclooxygenase-2 expression via suppressing NF-kB and JNK p38 MAPK activation pathways I-Ni Hsieh 1 Anita Shin-Yuan Chang1 Che-Ming Teng2 Chien-Chih Chen3 and Chia-Ron Yang1 Abstract Objectives Natural products have played a significant role in drug discovery and development. Inflammatory mediators such as inducible nitric oxide synthase iNOS and cyclooxygenase-2 COX-2 have been suggested to connect with various inflammatory diseases. In this study we explored the anti-inflammatory potential of aciculatin 8- 2R 4S 5S 6R -tetrahydro-4 5-dihydroxy-6-methyl-2H-pyran-2-yl -5-hydroxy-2- 4-hydroxyphenyl -7-methoxy-4H-chromen-4-one one of main components of Chrysopogon aciculatis by examining its effects on the expression and activity of iNOS and COX-2 in lipopolysaccharide LPS -activated macrophages. Methods We used nitrate and prostaglandin E2 PGE2 assays to examine inhibitory effect of aciculatin on nitric oxide NO and PGE2 levels in LPS-activated mouse macrophages and further investigated the mechanisms of aciculatin suppressed LPS-mediated iNOS COX-2 expression by western blot RT-PCR reporter gene assay and confocal microscope analysis. Results Aciculatin remarkably decreased the LPS 1 gg mL -induced mRNA and protein expression of iNOS and COX-2 as well as their downstream products NO and PGE2 respectively in a concentration-dependent manner 1-10 gM . Such inhibition was found via immunoblot analyses reporter gene assays and confocal microscope observations that aciculatin not only acts through significant suppression of LPS-induced NF-kB activation an effect highly correlated with its inhibitory effect on LPS-induced IkB .