Comparison of the chemical constitution and bioactivity among different parts of Lonicera japonica Thunb.

Lonicera japonica Thunb is a common herb in East Asia. The flower buds are usually regarded as the traditional medicinal part, while leaves and stems are considered less valuable and receive little attention. This study compared the chemical constituents and anti-inflammatory effects of the different tissues of Lonicera japonica Thunb for the first time.Thirty compounds were identified by UPLC-PDA-Q/TOF-MS/MS analysis. Hydroxycinnamic acids, flavonoids and iridoids were identified as the major components. The flower buds (FLJ), leaves (LLJ) and stems (SLJ) of Lonicera japonica Thunb showed great similarities in chemical components. Therein, LLJ contained higher level of hydroxycinnamic acids and flavonoids than FLJ and SLJ. Furthermore, FLJ, LLJ and SLJ exhibited potent anti-inflammatory activities in croton oil induced ear edema and carrageenan-induced paw edema essay in mice. Moreover, FLJ, LLJ and SLJ showed cytoprotective effect on LPS stimulated RAW 264.7 macrophages. LPS-induced increases of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) were suppressed by treatments of FLJ, LLJ and SLJ, respectively. LLJ possessed stronger anti-inflammatory effect than FLJ.Leaves and stems of Lonicera japonica Thunb have chemical components and anti-inflammatory properties similar to flower buds, and may become alternative or supplementary sources of flower buds. This article is protected by copyright. All rights reserved.