Potent inhibition of human neutrophil activations by bractelactone, a novel chalcone from Fissistigma bracteolatum

作者：Wu Yang Chang; Sureshbabu Munisamy; Fang Yao Ching; Wu Yi Hsiu; Lan Yu Hsuan; Chang Fang Rong; Chang Ya Wen; Hwang Tsong Long^*

来源：Toxicology and Applied Pharmacology, 2013, 266(3): 399-407.

DOI：10.1016/j.taap.2012.11.021

• Bractelactone
• Calcium
• Elastase
• Fissistigma bracteolatum
• Neutrophils
• Superoxide anion

Fissistigma bracteolatum is widely used in traditional medicine to treat inflammatory diseases. However, its active components and mechanisms of action remain unclear. In this study, (3Z)-6,7-dihydroxy-4-methoxy-3-(phenylmethylidene)-5-(3-phenylpropanoyl)-1-benzofuran-2(3H) (bractelactone), a novel chalcone from F. bracteolatum, showed potent inhibitory effects against superoxide anion (O-2(center dot-)) production, elastase release, and CD11b expression in formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP)-induced human neutrophils. However, bractelactone showed only weak inhibition of phorbol myristate acetate-caused O-2(center dot-) production. The peak cytosolic calcium concentration ([Ca2+](i)) was unaltered by bractelactone in FMLP-induced neutrophils, but the decay time of [Ca2+](i) was significantly shortened. In a calcium-free solution, changes in [Ca2+](i) caused by the addition of extracellular Ca2+ were inhibited by bractelactone in FMLP-activated cells. In addition, bractelactone did not alter the phosphorylation of p38 MAPK, ERK, JNK, or AKT or the concentration of cAMP. These results suggest that bractelactone selectively inhibits store-operated calcium entry (SOCE). In agreement with this concept, bractelactone suppressed sustained [Ca2+](i) changes in thapsigargin-activated neutrophils. Furthermore, bractelactone did not alter FMLP-induced formation of inositol 1,4,5-triphosphate. Taken together, our results demonstrate that the anti-inflammatory effects of bractelactone, an active ingredient of F. bracteolatum, in human neutrophils are through the selective inhibition of SOCE.

• 出版日期2013-2-1
• 单位中国医科大学; 长春大学