Anti-inflammatory germacrane-type sesquiterpene lactones from Vernonia sylvatica

Abstract

Nine new germacranolides, sylvaticalides A−H (1-9), and three known analogues (10-12) were isolated from the aerial part of Vernonia sylvatica. Their structures were established using comprehensive spectroscopic analysis, including high-resolution electrospray ionization mass spectroscopy (HR-ESI-MS) and 1D and 2D nuclear magnetic resonance (NMR) spectra. Their absolute configurations were determined by X-ray diffraction experiments. The anti-inflammatory activities of all isolated compounds were assessed by evaluating their inhibitory effects on the nuclear factor kappa B (NF-κB) pathway, which was activated by lipopolysaccharide (LPS)-stimulated human THP1-Dual cells, and the interferon-stimulated gene (ISG) pathway, activated by STING agonist MSA-2 in the same cell model. Compounds 1, 2 and 6 showed inhibitory effects on the NF-κB and ISG signaling pathways, with IC₅₀ values ranging from 4.12 to 10.57 μmol·L⁻¹.

Keywords

Vernonia sylvatica / Germacrane-type sesquiterpene lactone / Sylvaticalides A−H / Anti-inflammatory / NF-κB pathway / ISG pathway

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