Jae-Seok Shim

Antibacterial activity of xanthorrhizol from Curcuma xanthorrhiza against oral pathogens.

The antibacterial activity of xanthorrhizol, isolated from the methanol extract of Curcuma xanthorrhiza roots, was evaluated against oral microorganisms in comparison with chlorhexidine.

Screening of Thai medicinal plants for anticandidal activity

Medicinal plants are often used in the treatment of various ailments. In this study, 23 of Thai medicinal plants were screened for their anticandidal activity against six pathogenic Candida species: C. albicans, C. glabrata, C. guilliermondii, C. krusei, C. parapsilosis and C. tropicalis. The methanol extract of Hibiscus sabdariffa L. fruit, Trigonostemon reidioides (Kurz) Craib root, Usnea siamensis Vain whole plant, Boesenbergia rotunda (L.) Mansf. rhizome, and Albizia myriophylla Benth. stem showed anticandidal activity against one or more species of Candida. Among them, A. myriophylla Benth. showed broad anticandidal activity. The susceptibility tests of A. myriophylla Benth. extract, in terms of minimal inhibitory concentrations (MIC) and minimal fungicidal concentration (MFC), were performed by the broth microdilution techniques as described by the Clinical Laboratory Standard Institute. MICs of A. myriophylla Benth. extract to all Candida species was ranged 100–500 μg ml−1. The killing activity of A. myriophylla Benth. extract was fast acting against all Candida tested; the reduction in the number of CFU ml−1 was >3 log10 units (99.9%) in 2 h. This study indicates that A. myriophylla Benth. extract has considerable anticandidal activity, deserving further investigation for clinical applications for the treatment of candidiasis.

Inhibitory Effect of Panduratin A on UV-induced Activation of Mitogen-Activated Protein Kinases (MAPKs) in Dermal Fibroblast Cells

Exposure of the skin to ultraviolet (UV) induces photoaging associated with up-regulated matrix metalloproteinases (MMPs) activities and decreased collagen synthesis. We previously reported that panduratin A, a chalcone compound isolated from KAEMPFERIA PANDURATA Roxb ., decreased MMP-1 expression in UV-irradiated human skin fibroblasts. Here, we have investigated the effect of panduratin A on UV-induced activation of mitogen-activated protein kinases (MAPKs) signaling modules such as extracellular-regulated protein kinase (ERK), Jun-N-terminal kinase (JNK) and p38 kinase. Treatment with panduratin A in the range of 0.001 - 0.1 microM significantly inhibited UV-induced ERK, JNK and p38 activation. Moreover, inhibition of ERK, JNK and p38 by panduratin A resulted in decreased c-Fos expression and c-Jun phosphorylation induced by UV, which led to inhibition of activator protein-1 (AP-1) DNA binding activity. Panduratin A showed stronger activity than epigallocatechin 3- O-gallate (EGCG) known as a natural anti-aging agent. The results suggest that panduratin A can down-regulate UV-induced MMP-1 expression by inhibiting the MAPKs pathways and AP-1 activation. AP-1:activator protein-1 EGCG:epigallocatechin 3- O-gallate ERK:extracellular-regulated protein kinase JNK:c-Jun N-terminal kinase MAPK:mitogen-activated protein kinase MMP:matrix metalloproteinase UV:ultraviolet.

Immunostimulating Activity of Crude Polysaccharide Extract Isolated from Curcuma xanthorrhiza Roxb.

Curcuma xanthorrhiza Roxb., commonly known as Javanese turmeric, has been reported to possess a variety of biological activities, including anti-inflammatory effects, anticarcinogenic effects, wound healing effects, and serum cholesterol-lowering effects. CPE, crude polysaccharide extract isolated from the rhizome of C. xanthorrhiza using 0.1 N NaOH, consisted of arabinose (18.69%), galactose (14.0%), glucose (50.67%), mannose (12.97%), rhamnose (2.73%), and xylose (0.94%), with an average molecular weight of 33,000 Da. In the present study, we investigated the effect of CPE on nitric oxide (NO), hydrogen peroxide (H2O2), tumor necrosis factor-α (TNF-α), and prostaglandin E2 (PGE2) production in RAW 264.7 cells. The uptake of fluorescein-labeled Escherichia coli was measured to determine whether CPE stimulates the phagocytic activity of RAW 264.7 cells. CPE significantly increased the phagocytosis of macrophages and the release of NO, H2O2, TNF-α, and PGE2 in a dose-dependent manner, and showed a similar activity to lipopolysaccharide (LPS). To study the mechanisms of CPE, we examined induction of iNOS and COX-2. NO and PGE2 were produced as a result of stimulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) respectively. Both modulations of iNOS and COX-2 expression by CPE were evaluated by Western immunoblotting and RT-PCR. Since transcription of these enzymes is under the control of nuclear factor-kappa B (NF-κB), we assessed the phosphorylation of inhibitor κBα (IκBα) through Western immunoblotting. CPE clearly induced phosphorylation of IκBα, suggesting a role as an NF-κB activator. Taking all this together, we conclude that CPE isolated from Curcuma xanthorrhiza stimulates the immune functions of macrophages, which is mediated in part by specific activation of NF-κB.

The effect of 4-hydroxypanduratin A on the mitogen-activated protein kinase-dependent activation of matrix metalloproteinase-1 expression in human skin fibroblasts

BACKGROUND Exposure of ultraviolet (UV) light on the skin induces photoaging associated with up-regulated matrix metalloproteinases (MMPs) activities. The MMP-1 expression due to UV irradiation can be mediated by mitogen-activated protein kinases (MAPKs) such as extracellular signal-regulated kinase (ERK), Jun-N-terminal kinase (JNK) and p38 kinase activation. OBJECTIVE We investigated the effects of 4-hydroxypanduratin A, isolated from Kaempferia pandurata Roxb., on the expression of MMP-1 and activation of MAPKs signal pathways in UV-irradiated human skin fibroblasts. METHODS The fibroblasts were treated with 4-hydroxypanduratin A for indicated times and the cells were irradiated with UVB. MMP-1 protein expression and phosphorylation of MAPKs were determined by Western blot. Activator protein-1 (AP-1) DNA binding activity was investigated using electrophoretic mobility shift assay (EMSA). RESULTS 4-Hydroxypanduratin A in the range of 0.001-0.1microM significantly reduced the expression of MMP-1 levels and inhibited UV-induced MAPKs activation. Moreover, inhibition of MAPKs by 4-hydroxypanduratin A resulted in decreasing c-Fos expression and c-Jun phosphorylation induced by UV, which led to inhibiting AP-1 DNA binding activity. CONCLUSIONS The results suggest that 4-hydroxypanduratin A can be a potential candidate for the prevention and treatment of skin aging brought about by UV.

The effect of xanthorrhizol on the expression of matrix metalloproteinase‐1 and type‐I procollagen in ultraviolet‐irradiated human skin fibroblasts

Matrix metalloproteinases (MMPs) are key regulators of the skin photoaging process that is set in motion by exposure to ultraviolet (UV) irradiation. This skin damage results from UV‐induced generation of reactive oxygen species, which are associated with upregulation of MMPs and decreased collagen synthesis. We investigated the effects of xanthorrhizol, isolated from Curcuma xanthorrhiza, on the expression of MMP‐1 and type‐I procollagen in UV‐irradiated human skin fibroblasts. Fibroblasts cultured in the presence or absence of purified xanthorrhizol or C. xanthorrhiza extract were irradiated with UV (20 mJ/cm2), and MMP‐1 and type‐I procollagen levels were measured using Western blot analysis. Xanthorrhizol (0.001–0.1 µM) and C. xanthorrhiza extract (0.01–0.5 µg/mL) induced a significant, dose‐dependent decrease in the expression of MMP‐1 protein, and increased the expression of type‐1 procollagen. At a concentration of 0.1 µM, xanthorrhizol nearly completely abrogated MMP‐1 expression. The MMP‐1‐suppressing and type‐1 procollagen‐inducing effects of xanthorrhizol treatment were greater than those of epigallocatechin 3‐O‐gallate (EGCG), which is known to be a natural anti‐aging agent. These results suggest that xanthorrhizol is a potential candidate for the prevention and treatment of skin aging. Copyright

Antibacterial activity of xanthorrhizol isolated from Curcuma xanthorrhiza Roxb. against foodborne pathogens.

Xanthorrhizol, isolated from the ethanol extract of Curcuma xanthorrhiza Roxb., is a sesquiterpene compound with a molecular weight of 218. The aim of this study was to investigate the antibacterial activity of xanthorrhizol against foodborne pathogens. The antibacterial activity of xanthorrhizol was measured in terms of the MIC and the MBC. MICs and MBCs of xanthorrhizol against Bacillus cereus, Clostridium perfringens, Listeria monocytogenes, Staphylococcus aureus, Salmonella Typhimurium, and Vibrio parahaemolyticus were 8, 16, 8, 8, 16, 8 microg/ml and 16, 32, 16, 16, 16, 16 microg/ml, respectively. The bactericidal study, as determined by the viable cell count method, revealed that xanthorrhizol treatment at 4 x MIC reduced viable cells by at least 6 to 8 log for all six foodborne pathogens in 4 h. Xanthorrhizol maintained its antibacterial activity after thermal treatments (121 degrees C, 15 min) under various pH ranges (pH 3.0, 7.0, and 11.0). These results strongly suggest that xanthorrhizol, conferring strong antibacterial activity with thermal and pH stability, can be effectively used as a natural preservative to prevent the growth of foodborne pathogens.

Matrix metalloproteinase-1 inhibitory activity of Kaempferia pandurata Roxb.

Matrix metalloproteinase (MMP)-1 is a superfamily of zinc-dependent endopeptidases that are capable of degrading all components of the extracellular matrix. Kaempferia pandurata extract (0.01-0.5 microg/mL) significantly reduced the expression of MMP-1 and induced the expression of type 1 procollagen at the protein and mRNA levels in a dose-dependent manner. Ultraviolet (UV)-induced MMP-1 initiates cleavage of fibrillar collagen. Once cleaved by MMP-1, collagen can be further degraded by elevated levels of MMP-3 and MMP-9. It was found that increased MMP-1 expression due to UV irradiation was mediated by activation of mitogen-activated protein kinases such as extracellular-regulated kinase (ERK), Jun N-terminal kinase (JNK), and p38 kinase. Treatment of K. pandurata extract in the range of 0.01-0.5 microg/mL inhibited the UV-induced phosphorylations of ERK, JNK, and p38, respectively. Moreover, inhibition of phosphorylated ERK, JNK, and p38 by K. pandurata extract resulted in decreased c-Fos expression and c-Jun phosphorylation induced by UV light. The results strongly suggest that K. pandurata is potentially useful for the prevention and treatment of skin aging.