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Araliasaponin II (AS II) is a bioactive compound isolated from Acanthopanax henryi (Oliv.) Harms, a plant widely used in traditional oriental medicine. The present study investigated the anti-inflammatory effects of AS II using murine macrophages. The effects of AS II on inflammatory mediator and cytokine production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells was evaluated. Nitric oxide (NO) and cytokine production were determined using the Griess reagent and an ELISA kit. The expression levels of cytokines, inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) mRNA were examined by reverse transcription-quantitative polymerase chain reaction. The expression levels of iNOS, COX-2 and toll-like receptor (TLR)-4 protein were examined by western blotting. Translocation of nuclear factor-κB (NF-κB) and TLR-4 expression were visualized by immunofluorescence staining. AS II markedly inhibited the production of NO and prostaglandin E2, and reduced iNOS and COX-2 expression at the transcriptional and translational levels. AS II downregulated the expression of interleukin-6 and tumor necrosis factor-a at the protein and mRNA levels. Furthermore, pre-treatment with AS II significantly suppressed the TLR-4-NF-κB signaling pathway; this effect may be cause by AS II competing with LPS for binding to TLR-4 and subsequently inhibiting translocation of the NF-κB/p65 protein to the nucleus. The results suggested that the anti-inflammatory properties of AS II may result from inhibiting pro-inflammatory mediators by suppressing the initiation of the inflammatory response and inhibiting TLR-4-NF-κB signaling pathways. [ABSTRACT FROM AUTHOR]

Background: Black ginseng (Panax ginseng C. A. Meyer), three to nine times-steamed and dried ginseng, has biological and pharmacological activities. In this study, the anti-diabetic effects of the black ginseng ethanol extract (GBG05-FF) in typical type 2 diabetic model db/db mice were investigated. Methods: The effect of GBG05-FF in Type 2 diabetic mice was investigated by their blood analysis, biological mechanism analysis, and histological analysis. Results: The mice group treated with GBG05-FF showed decreased fasting blood glucose and glucose tolerance compared to that of the nontreated GBG05-FF group. In the blood analysis, GBG05-FF decreased main plasma parameter such as HbA1c, triglyceride, and total-cholesterol levels related to diabetes and improved the expression of genes and protein related to glucose homeostasis and glucose uptake in the liver and muscle. The histological analysis result shows that GBG05-FF decreased lipid accumulation in the liver and damage in the muscle. Moreover, GBG05-FF increased the phosphorylation of the AMPK in the liver and upregulated the expression of GLUT2 in liver and GLUT4 in muscle. Therefore, the mechanisms of GBG05-FF may be related to suppressing gluconeogenesis by activating AMPK in the liver and affecting glucose uptake in surrounding tissues via the upregulation of GLUT2 and GLUT4 expression. Conclusion: These findings provided a new insight into the anti-diabetic clinical applications of GBG05-FF and it might play an important role in the development of promising functional foods and drugs from the viewpoint of the chemical composition and biological activities. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus produces a number of virulence factors. The major virulence factors exhibited by S. aureus include various antigens, enzymes, cytotoxins and exotoxins (e.g. hemolysins, enterotoxins and toxic shock syndrome toxin). In this report, we show the influence of punicalagin on the secretion of exoprotein from S. aureus by western blotting, tumor necrosis factor (TNF) release assay and quantitative RT-PCR. When added to S. aureus cultures at an OD600 of 0.9, graded subinhibitory concentrations of punicalagin reduced the production of α-toxin, SEA and SEB in methicillin-resistant Staphylococcus aureus in a dose-dependent manner. Consistently, punicalagin reduced TNF-inducing activity by S. aureus culture supernatants. Here, the transcriptional level of agr (accessory gene regulator) in S. aureus was inhibited by punicalagin, suggesting that the reduced transcription may affect the secretion of exotoxins. These findings suggest that the expression of α-toxin and enterotoxins in S. aureus is sensitive to the action of punicalagin, which may be an advantageous candidate in the treatment of toxigenic staphylococcal disease. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the unknown mechanisms underlying the anti-inflammatory activity of Ciwujianoside C3 (CJS C3), extracted from the leaves of Acanthopanax henryi Harms, on lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Cells were treated with CJS C3 for 1 h prior to the addition of 200 ng/ml LPS. Cell viability was measured using the MTS assay. Nitric oxide levels were determined by Griess assay. Proinflammatory cytokine production was measured by enzyme-linked immunosorbent assay. The expression levels of cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS), and mitogen-activated protein kinases (MAPKs) were investigated by western blotting, reverse transcription (RT)-polymerase chain reaction (PCR) and RT-quantitative PCR. Nuclear factor (NF)-κB/p65 localization, and interaction of the TLR4 receptor with LPS was examined by immunofluorescence assay. The results indicated that CJS C3 exhibited no cytotoxicity at the measured concentrations. Treatment with CJS C3 inhibited NO production, proinflammatory cytokine levels, including interleukin (IL)-6, tumor necrosis factor (TNF)-α, and prostaglandin E2 (PGE2), and protein and mRNA expression levels of iNOS and COX-2. Furthermore, CJS C3 suppressed phosphorylation of extracellular signal-regulated kinases and c-jun N-terminal kinases. It was also able to suppress activation of NF-κB via inhibition of the TLR4 signaling pathway. These results suggested that CJS C3 exerts inhibitory effects on LPS-induced PGE2, NO, IL-6 and TNF-α production. In addition, iNOS and COX-2 expression was decreased in murine macrophages. These inhibitory effects may be achieved via suppression of MAPKs and NF-κB phosphorylation following inhibition of the TLR4 signaling pathway. [ABSTRACT FROM AUTHOR]

Oxyresveratrol (ORV) is a naturally occurring compound found in mulberries that exhibits a wide spectrum of biological activities. However, the underlying mechanism of the action of ORV against the methicillin-resistant S. aureus (MRSA) pathogen has not yet been reported. MRSA is multidrug-resistant, causing skin and other types of infections. The aim of the present study was to examine the antimicrobial activity of ORV and the underlying mechanism of its action on MRSA. The antibacterial activity of ORV was evaluated using a minimum inhibitory concentration (MIC) assay, and the mechanism of its antibacterial action on S. aureus was investigated using a combination of ORV with detergent, ATPase inhibitors and peptidoglycan (PGN). In addition, the survival characteristics and changes in MRSA morphology were monitored using transmission electron microscopy (TEM). The MIC value of ORV against all S. aureus strains was found to be 125 µg/ml. The optical density at 600 nm of each suspension treated using a combination of ORV with Triton X-100, N,N'-dicyclohexylcarbodiimide or sodium azide was reduced by 68.9-89.8% compared with the value upon treatment with ORV alone. In the ORV and PGN combination assay, direct binding of ORV with PGN from S. aureus was evident. Furthermore, TEM examination of MRSA treated with ORV showed alterations in septa formation. In conclusion, these results showed that ORV has a strong antibacterial effect against S. aureus, mainly by increasing membrane permeability and inhibiting ATPase when combined with other drugs. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) infection has become a serious clinical problem worldwide, and alternative natural or combination drug therapies are required for its treatment. The aim of the present study was to examined the antimicrobial activity of luteolin (LUT) against MRSA. Luteolin is a polyphenolic flavonoid compound with a wide spectrum of biological activities. The antimicrobial activities of LUT and the antibiotics ampicillin (AM), oxacillin (OX) and gentamicin (GT), used alone or in combination, were evaluated against five clinical MRSA isolates and two reference strains using a minimum inhibitory concentration (MIC) assay, MTT colorimetric assay, checkerboard dilution test and time-kill assay. The MIC of LUT against all strains was found to be 62.5 μg/ml. The combinations of LUT and antibiotics exhibited a synergistic effect against MRSA in the majority of cases, as determined by the checkerboard method. Time-kill curves revealed that a combination of LUT with AM, OX or GT significantly reduced bacterial counts, which dropped below the lowest detectable limit after 24 h. These results indicate that LUT potentiates the effects of β-lactam and aminoglycoside antibiotics against MRSA. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) infection is a serious clinical problem worldwide. The aim of the present study was to examine the antimicrobial activity of oxyresveratrol (ORV) against MRSA. The antimicrobial activity of ORV was evaluated against three strains of MRSA and one methicillin-susceptible S. aureus (MSSA) strain using a minimal inhibitory concentration (MIC) assay, MTT colorimetric assay, checkerboard dilution test and time-kill assay. The MIC of ORV for all strains was moderate at 125 µg/ml. Of note, the antimicrobial activity and fractional inhibitory concentration index values of ORV were markedly increased in the presence of a non-growth inhibitory dose of certain antibiotics. Time-kill curves revealed that a combination of ORV with ciprofloxacin or with gentamicin reduced bacterial counts to below the lowest detectable limit after 24 h. These effective combinations may be used as potential antimicrobial regimens for use in the management of MRSA. [ABSTRACT FROM AUTHOR]

Curcumin, a natural polyphenolic flavonoid extracted from the rhizome of Curcuma longa L., was shown to possess superior potency to resensitize methicillin-resistant Staphylococcus aureus (MRSA) to antibiotics. Previous studies have shown the synergistic activity of curcumin with β-lactam and quinolone antibiotics. Further, to understand the anti-MRSA mechanism of curcumin, we investigated the potentiated effect of curcumin by its interaction in diverse conditions. The mechanism of anti-MRSA action of curcumin was analyzed by the viability assay in the presence of detergents, ATPase inhibitors and peptidoglycan (PGN) from S. aureus, and the PBP2a protein level was analyzed by western blotting. The morphological changes in the curcumin-treated MRSA strains were investigated by transmission electron microscopy (TEM). We analyzed increased susceptibility to MRSA isolates in the presence of curcumin. The optical densities at 600 nm (OD600) of the suspensions treated with the combinations of curcumin with triton X-100 and Tris were reduced to 63% and 59%, respectively, compared to curcumin without treatment. N,N'-dicyclohexylcarbodiimide (DCCD) and sodium azide (NaN3) were reduced to 94% and 55%, respectively. When peptidoglycan (PGN) from S. aureus was combined with curcumin, PGN (0-125 µg/mL) gradually blocked the antibacterial activity of curcumin (125 µg/mL); however, at a concentration of 125 µg/mL PGN, it did not completely block curcumin. Curcumin has a significant effect on the protein level of PBP2a. The TEM images of MRSA showed damage of the cell wall, disruption of the cytoplasmic contents, broken cell membrane and cell lysis after the treatment of curcumin. These data indicate a remarkable antibacterial effect of curcumin, with membrane permeability enhancers and ATPase inhibitors, and curcumin did not directly bind to PGN on the cell wall. Further, the antimicrobial action of curcumin involved in the PBP2a-mediated resistance mechanism was investigated. [ABSTRACT FROM AUTHOR]

Carvone is one of the naturally occurring monoterpenes, the largest class of secondary metabolites in plants, and exists in two enantiomers, R-carvone (R-car) and S-car. The objective of this study was to investigate the antimicrobial activity of R-car and S-car with gentamicin (GET) against methicillin-resistant Staphylococcus aureus (MRSA). MRSA is a major human pathogen that causes serious problems, including hospital-acquired pneumonia, abscesses and surgical wound infections. Nosocomial MRSA infections often exhibit multidrug resistance. In the present study, antimicrobial susceptibility testing was performed with R-car, S-car and GET using the broth microdilution method. Minimal inhibitory concentration values for R- and S-car against six different strains of S. aureus ranged between 500 and 1,000 µg/ml. Anti-MRSA activity was evaluated using the checkerboard and time-kill assays to investigate the potential synergistic effects of different combinations of the carvone enantiomers and GET. R-car plus S-car, R-car plus GET and S-car plus GET exhibited significant synergistic activity against MRSA. These findings suggest that the single-agent anti-MRSA activities of R-car, S-car and GET are effectively increased through combination therapy. This study showed that carvone may be a potential adjuvant antimicrobial agent. [ABSTRACT FROM AUTHOR]

Six new cyclic peroxides (1-6) were isolated from the Korean sponge Plakortis simplex, along with two new alkylpyridinium alkaloids (7 and 8). The structures of these compounds were completely determined by a combination of NMR analysis and chemical reactions. Compounds 1-6 exhibited cytotoxic/antifungal activities against RAW264.7 cells and Candida albicans. [ABSTRACT FROM AUTHOR]

Platycodon grandiflorum (Campanulaceae) is used as traditional medicine in Asian countries. In Korean traditional medicine, Platycodon root has been widely used since ancient times as a traditional drug to treat cold, cough and asthma. However, its effects on bone marrow-derived mast cell (BMMC)-mediated allergy and inflammation mechanisms remain unknown. In this study, the biological effect of Platycodon root ethanol extract (PE) was evaluated in BMMC after induction of allergic mediators by phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187 (A23187) stimulation. The effect of PE on the production of several allergic mediators, such as interleukin-6 (IL-6), prostaglandin D2 (PGD2), leukotriene C4 (LTC4), β-Hexosaminidase (β-Hex) and cyclooxygenase-2 (COX-2) protein, was investigated. The results demonstrate that PE inhibits PMA + A23187 induced production of IL-6, PGD2, LTC4, β-Hexosaminidase and COX-2 protein. Taken together, these results indicate that PE has the potential for use in the treatment of allergy. [ABSTRACT FROM AUTHOR]

Luteolin (3′,4′,5,7-tetrahydroxylflavone) is a plant flavonoid and pharmacologically active agent that has been isolated from several plant species. In the present study, the effect of luteolin from the flowers of Lonicera japonica on phorbol 12-myristate 13-acetate (PMA) plus A23187-induced mast cell activation was examined. Luteolin significantly inhibited the induction of inflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-8, IL-6 and granulocyte-macrophage colonystimulating factor (GM-CSF) by PMA plus A23187. Moreover, luteolin attenuated cyclooxygenase (COX)-2 expression and intracellular Ca2+ levels. In activated HMC-1 cells, the phosphorylation of extra-signal response kinase (ERK 1/2) and c-jun N-terminal Kinase (JNK 1/2), but not p38 mitogen-activated protein kinase (p38 MAPK) were decreased by treatment of the cells with luteolin. Luteolin inhibited PMA plus A23187- induced nuclear factor (NF)-κB activation, IκB degradation, and luciferase activity. Furthermore, luteolin suppressed the expression of TNF-α, IL-8, IL-6, GM-CSF, and COX-2 through a decrease in the intracellular Ca2+ levels, and also showed a suppression of the ERK 1/2, JNK 1/2, and NF-κB activation. These results indicated that luteolin from the flowers of Lonicera japonica exerted a regulatory effect on mast cell-mediated inflammatory diseases, such as RA, allergy disease and IBD. [ABSTRACT FROM AUTHOR]

Methyl gallate is a major component of Galla Rhois, as carvacrol is of oregano essential oils. Both have shown good antibacterial activity against intestinal bacteria. This study investigated the antibacterial activities of nalidixic acid in combination with methyl gallate and carvacrol against nalidixic acid resistant bacteria. The combined effect of nalidixic acid with methyl gallate and carvacrol was evaluated using the checkerboard method to obtain a fractional inhibitory concentration index. The results showed that the combinations of nalidixic acid + methyl gallate/carvacrol improved nalidixic acid resistant pathogenic bacteria inhibition with synergy or partial synergy activity. Thus, a strong bactericidal effect of the drug combinations was observed. In vitro data thus suggested that nalidixic acid combined with methyl gallate and carvacrol may be microbiologically beneficial, rather than antagonists. [ABSTRACT FROM AUTHOR]

A rapid and simple method to determine methylmercury in natural crude medicine of animal origin was developed using gas chromatography electron capture detection (GC-ECD). Methylmercury, one of the forms of organomercury in nature, is much more toxic than inorganic and elemental mercury due to its lipid soluble property. The method is based on acidic digestion in hydrochloric acid solution following the extraction with toluene. The following parameters for the determination of methylmercury with GC-ECD were established: limit of detection 2 μg kg−1, limit of quantification 8 μg kg−1, linearity 10–300 ng mL−1, reproducibility as relative standard deviations 11.8%, 10.7% and 1.7% for 300, 150, and 20 ppb solutions, respectively, and recovery 87.1–112.4%. The results on animal-origin natural medicines using the method developed in this study were assured by comparison with those obtained by the method derived for measuring methylmercury in fish. [ABSTRACT FROM AUTHOR]

The extract of Angelicae Dahuricae Radix has traditionally been used as an anti-noceptive remedy in China. In this study, the methanol extract of Angelicae Dahuricae Radix (MEAD) was evaluated to determine if it has anti-noceptive and anti-inflammatory action. The anti-nociceptive activities of MEAD were evaluated by determining the writhing response and sleeping time, as well as by a formalin test. In addition, the anti-inflammatory activities of MEAD were evaluated by a vascular permeability test as well as by measuring the carrageenan-induced paw edema and conducting a myeloperoxidase (MPO) assay. MEAD (600 and 1200 mg/kg) exhibited anti-inflammatory effects on acetic acid-induced vascular permeability, carrageenan-induced paw edema, and MPO activity. Moreover, the results of the formalin test, the acetic acid-induced writhing response and the pentobarbital-induced sleeping time indicated that MEAD had anti-nociceptive effects that occurred in a concentration-dependent manner. To determine the mechanism by which MEAD exerted its effects on the expression of inducible nitric oxide synthase (iNOS) and the production of nitric oxide (NO) by treated murine macrophage RAW 264.7 cells was evaluated. Similar to the in vivo activities, both the iNOS expression and NO production were significantly suppressed by MEAD in a dose-dependent manner. Furthermore, MEAD inhibited the activating phosphorylation of ERK1/2. These results provide a scientific basis that explains the mechanism by which Angelicae Dahuricae Radix relieves inflammatory pain. [ABSTRACT FROM AUTHOR]