Carpesium divaricatum Sieb. & Zucc. Revisited: Newly Identified Constituents from Aerial Parts of the Plant and Their Possible Contribution to the Biological Activity of the Plant

Abstract

Carpesium divaricatum Sieb. & Zucc. has a long history of use as both a medicinal and a food plant. However, except for terpenoids, its chemical constituents have remained poorly investigated. The composition of hydroalcoholic extract from aerial parts of C. divaricatum was analyzed by HPLC-DAD-MSⁿ, revealing the presence of numerous caffeic acid derivatives that were formerly unknown constituents of the plant. In all, 17 compounds, including commonly found chlorogenic acids and rarely occurring butyryl and methylbutyryl tricaffeoylhexaric acids, were tentatively identified. Fractionation of lipophilic extract from cultivated shoots led to the isolation of 12-oxo-phytodienoic acid (12-OPDA), which is a newly identified constituent of the plant. The compound, at concentrations of 0.5, 1.0, and 2.5 μM, significantly reduced IL-8, IL-1β, TNFα, and CCL2 excretion by lipopolysaccharide (LPS)-stimulated human neutrophils. Reactive oxygen species (ROS) production induced by f-MLP was also significantly diminished in the neutrophils pretreated by 12-OPDA. The newly identified constituents of the plant seem to be partly responsible for its pharmacological activity and elevate the value of C. divaricatum as a potential functional food.

Keywords: 12-oxo-phytodienoic acid; Carpesium divaricatum; ROS; anti-inflammatory; caffeic acid derivatives; cytokines.

Figure 1

An HPLC-UV chromatogram of Carpesium divaricatum aerial part extract (10 mg/mL, 2 μL injected) acquired at 325 nm.

Figure 2

The chemical structure of (+)-trans-12-oxo-phytodienoic acid (trans-12-OPDA) isolated from aerial parts of Carpesium divaricatum Sieb. & Zucc.

Figure 3

Cytotoxic effects of trans-12-OPDA, at concentrations of 0.5, 1.0, and 2.5 μM, on lipopolysaccharide (LPS)-stimulated human neutrophils. Results are shown as percent of cells with diminished membrane integrity (propidium-iodide-positive cells, PI (+)). Control, untreated cells; LPS, cells stimulated with LPS (stimulated control). Statistical significance * p < 0.05, with reference to a stimulated control.

Figure 4

Inhibitory effects of trans-12-OPDA, at concentrations of 0.5, 1.0, and 2.5 μM, on reactive oxygen species (ROS) release from f-MLP-stimulated human neutrophils. Statistical significance *** p < 0.001, with reference to a stimulated control.

Figure 5

Inhibitory effects of trans-12-OPDA, at concentrations of 0.5, 1.0, and 2.5 μM, on IL-8 (A) and TNFα (B) secretion by LPS-stimulated human neutrophils. Statistical significance *** p < 0.001, with reference to a stimulated control.

Figure 6

Inhibitory effects of trans-12-OPDA, at concentrations of 0.5, 1.0, and 2.5 μM, on IL-1β (A) and CCL2 (B) secretion by LPS-stimulated human neutrophils. Statistical significance: * p < 0.05, *** p < 0.001, with reference to a stimulated control.