Simultaneous determination and anti-allergy effects of sesquiterpene lactones in Aucklandia lappa Decne

Aucklandia lappa Decne, a well-known traditional herbal medicine, is used for the treatment of asthma, rheumatism, coughs, tuberculosis, and many other diseases. We performed simultaneous analysis of three sesquiterpene lactones, costunolide (1), dehydrocostus lactone (2), and alantolactone (3), obtained from a 70% methanol extract of A. lappa using high-performance liquid chromatography-photodiode array techniques. In addition, we determined the inhibitory effects of the three components on the expression of chemokine mRNA in human keratinocyte HaCaT cells. The established analytical method showed high linearity, with a correlation coefficient ≥0.9999. The limit of detection and the limit of quantification of compounds 1 – 3 were 0.06 – 0.13 mg/mL and 0.21 – 0.42 mg/mL, respectively. The recovery of the compounds 1 – 3 was 97.27 – 103.00%. The intra- and inter-day relative standard deviations were 0.09 – 0.97% and 0.09 – 1.06%, respectively. Treatment with compounds 1 – 3 caused a significant reduction in the levels of mRNA for a range of chemokines, including thymus and activation-regulated chemokine (TARC/CCL17) and macrophage-derived chemokine (MDC/CCL22), and regulated on activation normal T-cell-expressed and secreted (RANTES/CCL5) chemokine and interleukin-8 in tumor necrosis factor-α and interferon-γ-stimulated HaCaT cells. We suggest that compounds 1 – 3 may be the active components of A. lappa that exhibit anti-atopic effects.