In vivoAnti-Inflammatory and Antinociceptive Effects of Liriodendrin Isolated from the Stem Bark ofAcanthopanax senticosus

Abstract

In the present study, liriodendrin isolated by activity-guided fractionation from the ethyl acetate (EtOAc) extracts of the stem bark of Acanthopanax senticosus, was evaluated for anti-inflammatory and antinociceptive activities. Liriodendrin (5, 10 mg/kg/day, p. o.) significantly inhibited the increase of vascular permeability induced by acetic acid in mice and reduced an acute paw edema induced by carrageenan in rats. When the analgesic activity was measured by the acetic acid-induced writhing test and hot plate test, liriodendrin showed a dose-dependent inhibition in animal models. In addition, syringaresinol, the hydrolysate of liriodendrin, more potently inhibited the LPS-induced production of NO, PGE 2 and TNF-alpha production of macrophages than liriodendrin. Consistent with these observations, the expression level of iNOS and COX-2 enzyme was decreased by syringaresinol in a concentration-dependent manner. These results suggest that the anti-inflammatory and antinociceptive effects of liriodendrin after oral administration were attributable to the in vivo transformation to syringaresinol, which may function as the active constituent.

Syringaresinol causes vasorelaxation by elevating nitric oxide production through the phosphorylation and dimerization of endothelial nitric oxide synthase

“…The lignan compound syringaresinol has been shown to inhibit inflammation in lipopolysaccharide-treated macriohages (Jung et al, 2003), gastric ulcer (Fujikawa et al, 1996), and oxidative injury of endothelial cells (Liu et al, 2009). Our previous results showed that another lignan compound sesamine promoted eNOS phosphorylation and NO production, which plays an important role in endothelial cell survival and angiogenesis (Chung et al, 2010), indicating that lignan compounds can increase NO production via eNOS phosphorylation.…”

Effect of plant extracts on H2O2-induced inflammatory gene expression in macrophages

“…Previous reports indicated that the isolated compounds from ES inhibit the NOS2 as well as COX2 expression 65,66. However, it has also been shown that 80% ethanol extract from ES attenuated LPS-induced NOS2 expression but not COX2 expression 20.…”

Anti-inflammatory Lignans from the Fruits of Acanthopanax sessiliflorus

“…Previous studies have already reported on the anti-inflammatory effects of components from A. sessiliflorus [11,12]. Since NO is known to play an important role in the inflammatory process, inhibitors of NO production are considered as potential anti-inflammatory agents [22].…”

“…Several previous studies have provided evidence for the anti-inflammatory effects of extracts and components from Acanthopanax species [10,11,12]. Therefore, isolated compounds 1 − 9 were evaluated for anti-inflammatory activities through the measurement of nitrite, a soluble oxidation product of nitric oxide (NO), in lipopolysaccharide (LPS)-induced RAW 254.7 macrophage cells.…”