Effect of six compounds isolated from rhizome of Anemone raddeana on the superoxide generation in human neutrophil

Eleutheroside K isolated from Acanthopanax henryi (Oliv.) Harms suppresses methicillin resistance of Staphylococcus aureus

Acanthopanax (A.) henryi (Oliv.) Harms contain many bioactive compounds commonly used in traditional Chinese medicine. The objective of the present study was to investigate the antibacterial activity of the single constituent, Eleutheroside K (ETSK) isolated from the leaves of A. henryi (Oliv.) Harms, against methicillin-resistant Staphylococcus (S.) aureus (MRSA). Broth microdilution assay was used to measure the minimal inhibitory concentration (MIC) and the MIC values of ETSK against eight clinical S. aureus strains were all 50 µg ml^-1 . At sub-inhibitory concentrations, a synergistic effect between oxacillin (OXA) and ETSK was confirmed using checkerboard dilution assay and time-kill curve analysis. The bacteriostatic effect became more pronounced when ETSK was used in combination with detergent (Triton X-100) or ATPase inhibitor (N, N'-dicyclohexylcarbodiimide). According to western blot analysis, the down-regulated expression of Penicillin-binding protein 2a (PBP2a) further validated that the bacterial activity was inhibited when treated with ETSK in a dose-dependent manner. Results based on our study verified that ETSK significantly suppressed MRSA infections and emphasized the potential application of ETSK as a novel anti-MRSA natural drug.

Quantitative and qualitative analyses of cytotoxic triterpenoids in the rhizomes of Anemone raddeana using HPLC and HPLC-ESI-Q/TOF-MS

Anemone raddeana Regel, a Traditional Chinese Medicine, has been demonstrated to possess cytotoxicity and anti-inflammatory activities. The purpose of this study is to establish analytical methods to identify and quantify the major active constituents in Anemone raddeana. A high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (HPLC-ESI-Q/TOF-MS) was used to identify the components in the title plant material. To quantify the major components, a HPLC-UV method was developed and validated. The results showed that 37 compounds were identified based on the MS data and retention times. The contents of eight main bioactive compounds were determined by HPLC simultaneously. These methods could be used to effectively evaluate the quality of A. raddeana and provide a valuable reference for further study. In addition, the cytotoxicity activity of the different fractions of A. raddeana was determined. Hederacolchiside A1 (f) showed promising activity against ten human cancer cell lines with IC₅₀ values from 0.29 to 3.48 μM.

Review of Anemone raddeana Rhizome and its pharmacological effects

The chemical compositions of Anemone raddeana Rhizome, a kind of traditional Chinese medicine, were reviewed, along with its bioactivity and pharmacological properties and method improvements of extracting and detecting triterpenoid saponins. A. raddeana Rhizome is used to treat neuralgia and rheumatism, and is rich in triterpenoid saponins, most of which are pentacyclic, with oleanane as the nucleus. So far, 37 triterpenoid saponins have been determined from the herb. Its reported bioactivity and pharmacological properties have been described as anticancerous, antimicrobial, anti-inflammatory, analgesic, antipyretic, anticonvulsive, antihistaminic, and sedative. It has also been used for the induction of the humoral immune response and treatment of liver fibrosis in chronic hepatitis. However, the herb also has hemolytic effects and can be toxic, which limits its clinical application. Further studies are needed on the pharmaceutical functions, mechanisms, and immunological responses to contribute to the herb's clinical applications.

Anemone medicinal plants: ethnopharmacology, phytochemistry and biology

The Ranunculaceae genus Anemone (order Ranunculales), comprising more than 150 species, mostly herbs, has long been used in folk medicine and worldwide ethnomedicine. Various medicinal compounds have been found in Anemone plants, especially triterpenoid saponins, some of which have shown anti-cancer activities. Some Anemone compounds and extracts display immunomodulatory, anti-inflammatory, antioxidant, and antimicrobial activities. More than 50 species have ethnopharmacological uses, which provide clues for modern drug discovery. Anemone compounds exert anticancer and other bioactivities via multiple pathways. However, a comprehensive review of the Anemone medicinal resources is lacking. We here summarize the ethnomedical knowledge and recent progress on the chemical and pharmacological diversity of Anemone medicinal plants, as well as the emerging molecular mechanisms and functions of these medicinal compounds. The phylogenetic relationships of Anemone species were reconstructed based on nuclear ITS and chloroplast markers. The molecular phylogeny is largely congruent with the morphology-based classification. Commonly used medicinal herbs are distributed in each subgenus and section, and chemical and biological studies of more unexplored taxa are warranted. Gene expression profiling and relevant "omics" platforms could reveal differential effects of phytometabolites. Genomics, transcriptomics, proteomics, and metabolomics should be highlighted in deciphering novel therapeutic mechanisms and utilities of Anemone phytometabolites.

Antagonism of human formyl peptide receptor 1 with natural compounds and their synthetic derivatives

Formyl peptide receptor 1 (FPR1) regulates a wide variety of neutrophil functional responses and plays an important role in inflammation and the pathogenesis of various diseases. To date, a variety of natural and synthetic molecules have been identified as FPR1 ligands. Here, we review current knowledge on natural products and natural product-inspired small molecules reported to antagonize and/or inhibit the FPR1-mediated responses. Based on this literature, additional screening of selected commercially available natural compounds for their ability to inhibit fMLF-induced Ca(2+) mobilization in human neutrophils and FPR1 transfected HL-60 cells, and pharmacophore modeling, natural products with potential as FPR1 antagonists are considered and discussed in this review. The identification and characterization of natural products that antagonize FPR1 activity may have potential for the development of novel therapeutics to limit or alter the outcome of inflammatory processes.

27-Hydroxyoleanolic Acid Type Triterpenoid Saponins from Anemone raddeana rhizome

Two new 27-hydroxyoleanolic acid type triterpenoid saponins were isolated from the rhizomes of Anemone raddeana Regel. The structures of the two compounds were elucidated as 27-hydroxyoleanolic acid 3-O-β-D-glucopyranosyl (1→2)-α-L-arabinopyranoside (1) and 3-O-α-L-rhamnopyranosyl (1→2)[β-D-glucopyranosyl (1→4)]-α-L-arabinopyranosyl-27-hydroxyoleanolic acid 28-O-α-L-rhamnopyranosyl (1→4)-β-D-glucopyranosyl (1→6)-β-D-glucopyranoside (2) on the basis of chemical and spectral evidence.

Two new triterpenoid saponins from rhizome of Anemone raddeana Regel

Two new 27-hydroxyoleanolic acid-type triterpenoid saponins, raddeanoside Ra (1) and raddeanoside Rb (2), were isolated from the rhizome of Anemone raddeana Regel. The structures of the two compounds were elucidated to be 27-hydroxyoleanolic acid 3-O-beta-D: -glucopyranosyl-(1 --> 4)-alpha-L: -arabinopyranoside (1) and 27-hydroxyoleanolic acid 3-O-alpha-L: -arabinopyranosyl-(1 --> 3)-alpha-L: -rhamnopyranosyl-(1 --> 2)-alpha- L: -arabinopyranoside (2) on the basis of chemical and spectral evidence.

Effect of five triterpenoid compounds isolated from root bark of Aralia elata on stimulus-induced superoxide generation, tyrosyl or serine/threonine phosphorylation and translocation of p47(phox), p67(phox), and rac to cell membrane in human neutrophils

Five triterpenoids; Congmuyanoside V, X, XI, XII, and XV (Cong. V, X, XI, XII, and XV) were isolated from the root bark of Aralia elata. The effect of these triterpenoids on stimulus-induced superoxide generation in human neutrophils was assayed by measuring the reduction of ferricytochrome c (cyt. c) using a dual-beam spectrophotometer. Translocation of p47(phox), p67(phox), and rac to the cell membrane and tyrosyl or serine/threonine phosphorylation of neutrophil proteins were investigated using specific monoclonal antibodies. The five triterpenoids used in the present experiment significantly suppressed N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced superoxide generation in concentration-dependent manner. Congmuyanoside V, XII, and XV also suppressed arachidonic acid (AA)-induced superoxide generation in high concentration. However, these triterpenoids showed no effect on phorbol 12-myristate 13-acetate (PMA)-induced superoxide generation. fMLP- and AA-induced tyrosyl phosphorylation and translocation of the cytosolic proteins p47(phox), p67(phox), and rac to the cell membrane were suppressed in parallel with the suppression of the stimulus-induced superoxide generation.

Effect of three triterpenoids, lupeol, betulin, and betulinic acid on the stimulus-induced superoxide generation and tyrosyl phosphorylation of proteins in human neutrophils

BACKGROUND

The roots of Anemone raddeana are used in Chinese folk medicine for curing rheumatism and neuralgia.

METHODS

The three triterpenoids lupeol, betulin and betulinic acid were isolated from ethanol extracts of the roots of A. raddeana. The effect of these triterpenoids on superoxide generation and tyrosyl phosphorylation of proteins in human neutrophils was investigated.

RESULTS

The superoxide generation induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) was significantly suppressed by betulin and lupeol depending on the concentration of the triterpenoids. The suppressive effect of betulinic acid was low. The phorbol 12-myristate 13-acetate (PMA)-induced superoxide generation was suppressed by betulin in a concentration-dependent manner, but not by lupeol and betulinic acid. In contrast, the superoxide generation induced by arachidonic acid (AA) was suppressed by lupeol, while betulin and betulinic acid weakly enhanced the AA-induced superoxide generation. Lupeol and betulin suppressed tyrosyl phosphorylation of a 45.0-kDa protein in fMLP-treated human neutrophils in parallel to the suppression of fMLP-induced superoxide generation, but betulinic acid did not. Lupeol, betulin and betulinic acid showed no hemolytic effect even at a concentration of 500 micromol/l.

CONCLUSIONS

Lupeol and betulin suppress superoxide generation by preventing tyrosyl phosphorylation of a 45.0-kDa protein in human neutrophils, and may have pharmaceutical applications.

Effect of five triterpenoid compounds isolated from leaves of Diospyros kaki on stimulus-induced superoxide generation and tyrosyl phosphorylation in human polymorphonuclear leukocytes

BACKGROUND

The crude drug "kaki-yô" is a traditional medicine used in Japan as a hypotensive drug.

METHODS

The effect of five triterpenoid compounds, isolated from leaves of Diospyros kaki on stimulus-induced superoxide generation and phosphorylation of tyrosine residues of protein in human neutrophils was investigated. The five compounds examined were alpha-amyrin (A), uvaol (UV), ursolic acid (UA), 19 alpha-hydroxy ursolic acid (HU) and 19 alpha,24-dihydroxy ursolic acid (DHU).

RESULTS

When the cells were preincubated with these compounds, the superoxide generation induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) was significantly suppressed in a concentration-dependent manner. These compounds also suppressed the superoxide generation induced by arachidonic acid (AA) in high concentrations. In the case of the superoxide generation induced by phorbol 12-myristate 13-acetate (PMA), UA, HU and DHU suppressed the superoxide generation but A and UV gave no effect. When the cells were incubated with fMLP in UA, HU and DHU, fMLP-induced tyrosyl phosphorylation of 45 kDa proteins of the cells was dose-dependently suppressed in parallel to the suppression of fMLP-induced superoxide generation.

CONCLUSIONS

Triterpenoid compounds suppress stimulus-induced superoxide generation and tyrosyl phosphorylation and may have pharmaceutical applications.

Effect of sarsasapogenin and its derivatives on the stimulus coupled responses of human neutrophils

METHODS

The effects of three sapogenins (sarsasapogenin, tigogenin and hecogenin) on the stimulus-induced superoxide generation and protein tyrosyl phosphorylation in human neutrophils were investigated.

RESULTS

When the cells were preincubated with sapogenin, three sapogenins dose-dependently suppressed the superoxide generations induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol 12-myristate 13-acetate (PMA), respectively. In both cases, their effects were in the order: sarsasapogenin>tigogenin>hecogenin. While sarsasapogenin suppressed the superoxide generation induced by arachidonic acid (AA) as well, the superoxide generation was scarcely suppressed by tigogenin and significantly enhanced by hecogenin. In parallel to their effects on the superoxide generation, the three sapogenins dose-dependently suppressed the fMLP-induced and PMA-induced tyrosyl phosphorylations of 45 kDa protein in neutrophils, respectively.

CONCLUSIONS

Of the sapogenins tested, sarsasapogenin may have the most clinical use as it suppresses superoxide generation.