Enhancement of an In Vivo Anti-Inflammatory Activity of Oleanolic Acid through Glycosylation Occurring Naturally in Stauntonia hexaphylla

Abstract

Stauntonia hexaphylla (Lardizabalaceae) has been used as a traditional herbal medicine in Korea and China for its anti-inflammatory and analgesic properties. As part of a bioprospecting program aimed at the discovery of new bioactive compounds from Korean medicinal plants, a phytochemical study of S. hexaphylla leaves was carried out leading to isolation of two oleanane-type triterpene saponins, 3-O-[β-d-glucopyranosyl (1→2)-α-l-arabinopyranosyl] oleanolic acid-28-O-[β-d-glucopyranosyl (1→6)-β-d-glucopyranosyl] ester (1) and 3-O-α-l-arabinopyranosyl oleanolic acid-28-O-[β-d-glucopyranosyl (1→6)-β-d-glucopyranosyl] ester (2). Their structures were established unambiguously by spectroscopic methods such as one- and two-dimensional nuclear magnetic resonance and infrared spectroscopies, high-resolution electrospray ionization mass spectrometry and chemical reactions. Their anti-inflammatory activities were examined for the first time with an animal model for the macrophage-mediated inflammatory response as well as a cell-based assay using an established macrophage cell line (RAW 264.7) in vitro. Together, it was concluded that the saponin constituents, when they were orally administered, exerted much more potent activities in vivo than their sapogenin core even though both the saponins and the sapogenin molecule inhibited the RAW 264.7 cell activation comparably well in vitro. These results imply that saponins from S. hexaphylla leaves have a definite advantage in the development of oral medications for the control of inflammatory responses.

Antiinflammatory activity of natural triterpenes—An overview from 2006 to 2021

“…Leaves of Stauntonia hexaphylla afforded two bioactive oleanane‐type triterpene saponins 226 and 227 . Their antiinflammatory activities were evaluated and both compounds exerted an inhibition of macrophage activation (Vinh et al, 2020).…”

“….Leaves of Stauntonia hexaphylla afforded two bioactive oleananetype triterpene saponins 226 and 227. Their antiinflammatory activities were evaluated and both compounds exerted an inhibition of macrophage activation(Vinh et al, 2020).Araloside C (228), a saponin extracted from Aralia elata, had a protective effect on macrophage polarization in investigated atherosclerosis. The results showed that this compound significantly reduced the plaque area in atherosclerotic mice and the accumulation of lipids in ox-LDL-treated macrophages, promoted M2 phenotype macrophage polarization, increased the number of autophagosomes, and modulated the expression of autophagy-related proteins mediated by Sirt1 (Y Luo, Lu, et al, 2020)…”

Characterisation of four new triterpenoid saponins with nitric oxide inhibitory activity from aerial parts of Gouania leptostachya

“…Cell cytotoxicity was evaluated using the 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The cytotoxicity activity was assayed according to previously reported methods with slight modification (Vinh et al 2020). Briefly, RAW264.7 cells suspended in DMEM medium (10% FBS) were seeded onto a 96-well culture plate at a density of 5 x 10 3 cells/100 μL.…”

Hepatoprotective Effects of Extract of Helicteres hirsuta Lour. on Liver Fibrosis Induced by Carbon Tetrachloride in Rats

“…Fifty adult Wistar rats were of both sexes, with no pregnancies, and weights of 200 ± 20 g. The healthy, agile, and fluffy animals were kept in stainless steel cages in rooms maintained at 25 • C on 12-h light/dark cycles and provided free access to standard diet and water. The experimental procedures were approved by the Animal Ethics Committee and animal experiments were carried out per the approved protocols [8,10].…”

“…In order to isolate and evaluate the hepatoprotective effects of the extract of H. hirsuta, this study mainly studied the total methanol (MeOH) extract, which was the optimal extract to isolate most of the compounds present in the plant, and to evaluate the hepatoprotective effect [7,8,10]. However, traditional medicinal herbs are often used in the form of brandy immersion (equivalent to Ethanol: Water extract (1/1, v/v)).…”