Downregulation of Matriptase Inhibits Porphyromonas gingivalis Lipopolysaccharide-Induced Matrix Metalloproteinase-1 and Proinflammatory Cytokines by Suppressing the TLR4/NF-κB Signaling Pathways in Human Gingival Fibroblasts.

Matriptases are cell surface proteolytic enzymes belonging to the type II transmembrane serine protease family that mediate inflammatory skin disorders and cancer progression. Matriptases may affect the development of periodontitis via protease-activated receptor-2 activity. However, the cellular mechanism by which matriptases are involved in periodontitis is unknown. In this study, we examined the antiperiodontitis effects of matriptase on Porphyromonas gingivalis-derived lipopolysaccharide (PG-LPS)-stimulated human gingival fibroblasts (HGFs). Matriptase small interfering RNA-transfected HGFs were treated with PG-LPS. The mRNA and protein levels of proinflammatory cytokines and matrix metalloproteinase 1 (MMP-1) were evaluated using the quantitative real-time polymerase chain reaction (qRT-PCR) and an enzyme-linked immunosorbent assay (ELISA), respectively. Western blot analyses were performed to measure the levels of Toll-like receptor 4 (TLR4)/interleukin-1 (IL-1) receptor-associated kinase (IRAK)/transforming growth factor ß-activated kinase 1 (TAK1), p65, and p50 in PG-LPS-stimulated HGFs. Matriptase downregulation inhibited LPS-induced proinflammatory cytokine expression, including the expression of IL-6, IL-8, tumor necrosis factor-α (TNF-α), and IL-Iß. Moreover, matriptase downregulation inhibited PG-LPS-stimulated MMP-1 expression. Additionally, we confirmed that the mechanism underlying the effects of matriptase downregulation involves the suppression of PG-LPS-induced IRAK1/TAK1 and NF-κB. These results suggest that downregulation of matriptase PG-LPS-induced MMP-1 and proinflammatory cytokine expression via TLR4-mediated IRAK1/TAK1 and NF-κB signaling pathways in HGFs.

Treatment with Commelina communis Extract Exerts Anti-inflammatory Effects in Murine Macrophages via Modulation of the Nuclear Factor-κB Pathway.

The incidence of severe inflammatory diseases caused by chronic inflammation has increased owing to unprecedented changes brought about by industrialization. In this study, we aimed to assess the effect of treatment of lipopolysaccharide- (LPS-) induced murine macrophages with Commelina communis Linne extract (CCE) on synthesis of nitric oxide (NO), hypersecretion of proinflammatory cytokines, intranuclear transition of the p65 subunit of nuclear factor- (NF-) κB, and degradation of the NF-κB inhibitor IκBα. Notably, CCE treatment did not affect cell viability even at a final concentration of 1.5 mg/mL. At a high concentration of CCE, the LPS-induced high levels of NO, tumor necrosis factor-α, interleukin- (IL-) 1ß, and IL-6 were decreased via downregulation of inducible NO synthase and proinflammatory cytokine mRNA expression. Furthermore, phosphorylation of IκBα was significantly decreased upon CCE treatment, and the intranuclear transition of NF-κB p65 triggered by LPS was inhibited at a high concentration of CCE. Polyphenols and flavonoids, secondary metabolites in CCE that regulate the NF-κB pathway, may be responsible for its anti-inflammatory activity. We suggest that CCE has anti-inflammatory effects related to suppression of the NF-κB pathway and can be used to treat chronic inflammation.

Evodiae fructus Extract Inhibits Interleukin-1ß-Induced MMP-1, MMP-3, and Inflammatory Cytokine Expression by Suppressing the Activation of MAPK and STAT-3 in Human Gingival Fibroblasts In Vitro.

Periodontitis is a Gram-negative bacterial infectious disease. Numerous inflammatory cytokines, including interleukin-1ß (IL-1ß), regulate periodontitis pathophysiology and cause periodontal tissue destruction. In human gingival fibroblasts (HGFs), IL-1ß stimulates the production of matrix metalloproteinases (MMPs) and proinflammatory cytokines via various mechanisms. Several transcription factors, such as signal transducer and activator of transcription 3 (STAT-3), activator protein 1 (AP-1), and nuclear factor-κB (NF-κB), regulate gene expression. Mitogen-activated protein kinases (MAPKs) regulate these transcription factors. However, the MAPK/STAT-3 activation signal in HGFs is unknown. We investigated the potential inhibitory effects of the extract of Evodiae fructus (EFE), the dried, ripe fruit of Evodia rutaecarpa, on MMP and proinflammatory cytokine expression in IL-1ß-stimulated HGFs. EFE inhibited the expression of MMP-1, MMP-3, and proinflammatory cytokines (TNF-α, IL-6, and IL-8) in IL-1ß-stimulated HGFs through the inhibition of IL-1ß-induced MAPK/STAT-3 activation. Also, these results suggest that the EFE may be a useful for the bioactive material for oral care.

Aqueous extract of Chrysanthemum morifolium Ramat. inhibits RANKL-induced osteoclast differentiation by suppressing the c-fos/NFATc1 pathway.

OBJECTIVE: The flower of chrysanthemum, used worldwide as a medicinal and edible product, has shown various bioactivities, such as anti-inflammatory, antioxidant, anti-tumorigenic, and hepatoprotective activities, as well as cardiovascular protection. However, the effect of Chrysanthemum morifolium Ramat. on the regulation of osteoclast differentiation has not yet been reported. In this study, we aimed to investigate the inhibitory effect of Chrysanthemum morifolium Ramat. water extract (CME) on RANKL-induced osteoclast differentiation in mouse bone marrow-derived macrophages (BMMs). STUDY DESIGN: Bone marrow-derived macrophages (BMMs) isolated from the C57BL/6 J mice. The viability of BMMs was detected with MTT assays. Inhibitory effects of CME on osteoclast differentiation and bone resorption was measured by TRAP staining and Pit assay. Osteoclast differentiation-associated gene expression were assessed by Real-time quantitative polymerase chain reaction. Intracellular signaling molecules was assessed by western blot. RESULTS: CME significantly inhibited osteoclast differentiation in BMMs without cytotoxicity, besides inhibiting MAPK/c-fos and PLCγ2/CREB activation. The inhibitory effects of CME on differentiation-related signaling molecules resulted in significant repression of NFATc1 expression, which is a key transcription factor in osteoclast differentiation, fusion, and activation. CONCLUSION: Our results confirmed the inhibition of RANKL-induced PLCγ2/CREB/c-fos/NFATc1 activation by CME during osteoclast differentiation. The findings collectively suggested CME as a traditional therapeutic agent for osteoporosis, RA, and periodontitis.

Weissella cibaria CMU exerts an anti­inflammatory effect by inhibiting Aggregatibacter actinomycetemcomitans­induced NF­κB activation in macrophages.

Periodontitis is a chronic inflammatory disease caused by various periodontal pathogens. Weissella cibaria CMU (oraCMU) is a probiotic that promotes oral health. However, its anti­inflammatory effects against periodontal pathogens have not yet been investigated. The present study evaluated the anti­inflammatory effects of live oraCMU against stimulation with the formalin­inactivated periodontal pathogen Aggregatibacter actinomycetemcomitans in RAW 264.7 macrophages. Cell viability was analyzed by the MTS assay in a dose­dependent manner (at multiplicities of infection of 0.1, 1, 10, 100 and 1,000). Nitric oxide (NO) was monitored using the Griess test. The mRNA expression of proinflammatory cytokines such as interleukin (IL)1ß and IL6 was assessed by reverse transcription­quantitative PCR. Western blotting was used to examine the effects of oraCMU on the phosphorylation of NF­κB inhibitor α (IκBα) and IκBα kinase (IKK), the nuclear translocation of the NF­κB subunit p65 and the expression of inducible NO synthase (iNOS). Live oraCMU had no cytotoxic effects on RAW 264.7 macrophages. In A. actinomycetemcomitans­stimulated RAW 264.7 macrophages, oraCMU reduced NO production by suppressing iNOS expression and downregulating the mRNA expression of proinflammatory cytokines in a dose­dependent manner. IKK phosphorylation and IκBα degradation were dose­dependently inhibited by oraCMU and the nuclear translocation of p65 via the canonical NF­κB pathway was simultaneously reduced. The results indicated that oraCMU possessed anti­inflammatory activity associated with the inhibition of NF­κB signal activation in response to periodontal pathogens. This suggests that oraCMU is a beneficial anti­inflammatory probiotic that can aid in the maintenance of oral health.

Reversine inhibits MMP-3, IL-6 and IL-8 expression through suppression of ROS and JNK/AP-1 activation in interleukin-1ß-stimulated human gingival fibroblasts.

OBJECTIVE: Periodontitis is an inflammatory disease of the supporting tissue around teeth commonly caused by gram-negative bacterial infections. Interleukin (IL)-1ß, a cytokine involved in host immune and inflammatory responses, is known to induce the activation of various intracellular signaling pathways. One of these signaling mechanisms involves the regulation of gene expression by activation of transcription factors (AP-1 and NF-κB). These transcription factors are controlled by mitogen-activated protein kinases (MAPKs), which increase cytokine and matrix metalloproteinase (MMP) expression. We examined the preventive effects of reversine, a 2,6-disubstituted purine derivative, on cytokine and MMP-3 expression in human gingival fibroblasts (HGFs) stimulated with IL-lß. STUDY DESIGN: Western blot analyses were performed to verify the activities of MAPK, p65, p50, and c-Jun and the expression of MMPs in IL-1ß-stimulated HGFs. Cytokine and MMP-3 expression in IL-1ß-stimulated HGFs was measured by real-time quantitative polymerase chain reaction. RESULTS: Reversine decreased the IL-1ß-induced expression of proinflammatory cytokines (IL-6 and IL-8) and MMP-3 in HGFs. Furthermore, the mechanism underlying the effects of reversine involved the suppression of IL-1ß-stimulated MAPK activation and AP-1 activation. CONCLUSION: Reversine inhibits IL-1ß-induced MMP and cytokine expression via inhibition of MAPK/AP-1 activation and ROS generation. Therefore, we suggest that reversine may be an effective therapeutic candidate for preventing periodontitis.

Artemisia princeps Inhibits Growth, Biofilm Formation, and Virulence Factor Expression of Streptococcus mutans.

This study was designed to determine whether the ethanol extract of Artemisia princeps could inhibit the cariogenic activity of Streptococcus mutans. The increase in acid production and biofilm formation by S. mutans were evaluated. The expression levels of virulence factor genes were determined by performing the real-time polymerase chain reaction (PCR). The bactericidal effect was tested by confocal laser scanning microscopy. The A. princeps extract was observed to inhibit the growth of S. mutans at concentrations >0.05 mg/mL (P < .05). After using the safranin staining method, we found that the A. princeps extract had an inhibitory effect against biofilm formation at a concentration of >0.05 mg/mL. These experimental results were similar to that observed with the scanning electron microscopy. The results of the confocal microscopy revealed that the A. princeps extract at high concentrations of 0.4-3.2 mg/mL showed a bactericidal effect in a concentration-dependent manner. According to the results of the real-time PCR analysis, it was observed that the A. princeps extract inhibited the expression of virulence factor genes. These results suggest that A. princeps may inhibit the cariogenic activity of S. mutans, and may be useful as an anticariogenic agent.

Korean National Oral Health Survey Data on the Symmetry of Primary Dentition Surface Caries.

OBJECTIVES: This study evaluated the intraoral symmetry of dental caries in primary teeth as part of a study of caries patterns in primary dentition. STUDY DESIGN: The data for 4,800 5-year-old and 4,379 8-year-old children in this study were from the 2012 Korean national oral health survey. Pearson correlation coefficients of the decayed and filled surface (dfs) values ranged from 0.436 (lower primary canines) to 0.835 (upper primary central incisors) for the right and left primary teeth and from 0.084 (right primary central incisor) to 0.457 (left primary second molar) for the upper and lower primary dentition (P< 0.01). RESULTS: The upper and lower dfs values differed significantly (P< 0.05) when the right and left primary second molars were excluded. The left or right primary data without caries ranged from 56.4% (lower of first and second primary molars) to 99.7% (lower primary central incisors). The bilateral caries among cases with one or more in the right or left primary teeth ranged from 25.0% (lower lateral primary incisor) to 72.7% (upper primary central incisors). CONCLUSIONS: These results suggested that dental caries in primary teeth show bilateral symmetry and differences in the degree of symmetry according to the teeth set or surface set of the homologous teeth.

Silencing of casein kinase 2 inhibits PKC­induced cell invasion by targeting MMP­9 in MCF­7 cells.

Casein kinase 2 (CK2) is a serine/threonine protein kinase that has been considered to represent an important factor in mammary tumorigenesis. Increased expression of matrix metalloproteinase­9 (MMP­9) via nuclear factor­κB (NF­κB) activation has been demonstrated to promote breast cancer cell invasion. In the present study, the involvement of CK2 in protein kinase C (PKC) induced cell invasion in MCF­7 breast cancer cells was investigated as well as the underlying molecular mechanisms. The mRNA and protein levels of MMP­9 in MCF­7 cells were investigated using reverse transcription­quantitative polymerase chain reaction, western blot analyses and a zymography assay. Cell invasiveness was investigated using a Matrigel invasion assay, and it was revealed that small interfering RNA specific for CK2 suppressed PKC induced cell invasion by regulating MMP­9 expression via activation of the p38 kinase/c­Jun N­terminal kinase/NF­κB pathway. In addition, it was demonstrated that CK2 inhibitors [apigenin (20 µM), emodin (20 µM) or 2­dimethylamino­4,5,6,7­tetrabromo­1H­benzimidazole (2 µM)] suppressed PKC induced cell invasion and MMP­9 expression. The results of the present study suggested that CK2 is an important factor involved in the induction of MCF­7 breast cancer cell invasion by PKC. Therefore, CK2 may represent novel candidates for therapy intended to inhibit invasion in breast cancer.

Chamaecyparis obtusa Suppresses Virulence Genes in Streptococcus mutans.

Chamaecyparis obtusa (C. obtusa) is known to have antimicrobial effects and has been used as a medicinal plant and in forest bathing. This study aimed to evaluate the anticariogenic activity of essential oil of C. obtusa on Streptococcus mutans, which is one of the most important bacterial causes of dental caries and dental biofilm formation. Essential oil from C. obtusa was extracted, and its effect on bacterial growth, acid production, and biofilm formation was evaluated. C. obtusa essential oil exhibited concentration-dependent inhibition of bacterial growth over 0.025 mg/mL, with 99% inhibition at a concentration of 0.2 mg/mL. The bacterial biofilm formation and acid production were also significantly inhibited at the concentration greater than 0.025 mg/mL. The result of LIVE/DEAD® BacLight™ Bacterial Viability Kit showed a concentration-dependent bactericidal effect on S. mutans and almost all bacteria were dead over 0.8 mg/mL. Real-time PCR analysis showed that gene expression of some virulence factors such as brpA, gbpB, gtfC, and gtfD was also inhibited. In GC and GC-MS analysis, the major components were found to be α-terpinene (40.60%), bornyl acetate (12.45%), α-pinene (11.38%), ß-pinene (7.22%), ß-phellandrene (3.45%), and α-terpinolene (3.40%). These results show that C. obtusa essential oil has anticariogenic effect on S. mutans.

Composition Analysis and Inhibitory Effect of Sterculia lychnophora against Biofilm Formation by Streptococcus mutans.

Pangdahai is a traditional Chinese drug, specifically described in the Chinese Pharmacopoeia as the seeds of Sterculia lychnophora Hance. Here, we separated S. lychnophora husk and kernel, analyzed the nutrient contents, and investigated the inhibitory effects of S. lychnophora ethanol extracts on cariogenic properties of Streptococcus mutans, important bacteria in dental caries and plaque formation. Ethanol extracts of S. lychnophora showed dose-dependent antibacterial activity against S. mutans with significant inhibition at concentrations higher than 0.01 mg/mL compared with the control group (p < 0.05). Furthermore, biofilm formation was decreased by S. lychnophora at concentrations > 0.03 mg/mL, while bacterial viability was decreased dose-dependently at high concentrations (0.04, 0.08, 0.16, and 0.32 mg/mL). Preliminary phytochemical analysis of the ethanol extract revealed a strong presence of alkaloid, phenolics, glycosides, and peptides while the presence of steroids, terpenoids, flavonoids, and organic acids was low. The S. lychnophora husk had higher moisture and ash content than the kernel, while the protein and fat content of the husk were lower (p < 0.05) than those of the kernel. These results indicate that S. lychnophora may have antibacterial effects against S. mutans, which are likely related to the alkaloid, phenolics, glycosides, and peptides, the major components of S. lychnophora.

Fisetin regulates TPA-induced breast cell invasion by suppressing matrix metalloproteinase-9 activation via the PKC/ROS/MAPK pathways.

Invasion and metastasis are among the main causes of death in patients with malignant tumors. Fisetin (3,3',4',7-tetrahydroxyflavone), a natural flavonoid found in the smoke tree (Cotinus coggygria), is known to have antimetastatic effects on prostate and lung cancers; however, the effect of fisetin on breast cancer metastasis is unknown. The aim of this study was to determine the anti-invasive activity of fisetin in human breast cancer cells. Matrix metalloproteinase (MMP)-9 is a major component facilitating the invasion of many cancer tumor cell types, and thus the inhibitory effect of fisetin on MMP-9 expression in 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated human breast cancer cells was investigated in this study. Fisetin significantly attenuated TPA-induced cell invasion in MCF-7 human breast cancer cells, and was found to inhibit the activation of the PKCα/ROS/ERK1/2 and p38 MAPK signaling pathways. This effect was furthermore associated with reduced NF-κB activation, suggesting that the anti-invasive effect of fisetin on MCF-7 cells may result from inhibited TPA activation of NF-κB and reduced TPA activation of PKCα/ROS/ERK1/2 and p38 MAPK signals, ultimately leading to the downregulation of MMP-9 expression. Our findings indicate the role of fisetin in MCF-7 cell invasion, and clarify the underlying molecular mechanisms of this role, suggesting fisetin as a potential chemopreventive agent for breast cancer metastasis.

Chamaecyparis obtusa Essential Oil Inhibits Methicillin-Resistant Staphylococcus aureus Biofilm Formation and Expression of Virulence Factors.

The emergence of antibiotic-resistant bacteria has caused difficulty in treating infectious diseases. Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most commonly recognized antibiotic-resistant bacteria. Novel antibiotics are urgently required to treat these bacteria. Raw materials derived from natural sources can be used for the development of novel antibiotics, such as Chamaecyparis obtusa (C. obtusa), which has been traditionally used in treating asthmatic disease. In this study, the antibacterial activity of the essential oil (EO) extracted from C. obtusa leaves against MRSA was investigated. MRSA growth and acid production from glucose metabolism were inhibited at concentrations greater than 0.1 mg/mL C. obtusa EO. MRSA biofilm formation was observed using scanning electron microscopy and safranin staining. C. obtusa EO inhibited MRSA biofilm formation at concentrations greater than 0.1 mg/mL. Using real-time polymerase chain reaction, mRNA expression of virulence factor genes, sea, agrA, and sarA, was observed. agrA expression was inhibited with C. obtusa EO concentrations greater than 0.2 mg/mL, whereas inhibition of sea and sarA expression was also observed at a concentration of 0.3 mg/mL. C. obtusa EO was analyzed by gas chromatography (GC) and GC coupled for mass spectrometry, which identified 59 constituents, accounting to 98.99% of the total EO. These findings suggest that C. obtusa EO has antibacterial effects against MRSA, which might be associated with the major components of C. obtusa EO, such as sabinene (19.06%), α-terpinyl acetate (16.99%), bornyl acetate (10.48%), limonene (8.54%), elemol (7.47%), myrcene (5.86%), γ-terpinene (4.04%), and hibaene (3.01%).

Inhibitory Effects of Chrysanthemum boreale Essential Oil on Biofilm Formation and Virulence Factor Expression of Streptococcus mutans.

The aim of the study was to evaluate the antibacterial activity of essential oil extracted from Chrysanthemum boreale (C. boreale) on Streptococcus mutans (S. mutans). To investigate anticariogenic properties, and bacterial growth, acid production, biofilm formation, bacterial adherence of S. mutans were evaluated. Then gene expression of several virulence factors was also evaluated. C. boreale essential oil exhibited significant inhibition of bacterial growth, adherence capacity, and acid production of S. mutans at concentrations 0.1-0.5 mg/mL and 0.25-0.5 mg/mL, respectively. The safranin staining and scanning electron microscopy results showed that the biofilm formation was also inhibited. The result of live/dead staining showed the bactericidal effect. Furthermore, real-time PCR analysis showed that the gene expression of some virulence factors such as gtfB, gtfC, gtfD, gbpB, spaP, brpA, relA, and vicR of S. mutans was significantly decreased in a dose dependent manner. In GC and GC-MS analysis, seventy-two compounds were identified in the oil, representing 85.42% of the total oil. The major components were camphor (20.89%), ß-caryophyllene (5.71%), α-thujone (5.46%), piperitone (5.27%), epi-sesquiphellandrene (5.16%), α-pinene (4.97%), 1,8-cineole (4.52%), ß-pinene (4.45%), and camphene (4.19%). These results suggest that C. boreale essential oil may inhibit growth, adhesion, acid tolerance, and biofilm formation of S. mutans through the partial inhibition of several of these virulence factors.

Decursin prevents TPA-induced invasion through suppression of PKCα/p38/NF-κB-dependent MMP-9 expression in MCF-7 human breast carcinoma cells.

Decursin, a coumarin compound, was first isolated from the roots of Angelica gigas almost four decades ago. It was found to exhibit cytotoxicity against various human cancer cells and to possess anti-amnesic activity in vivo through the inhibition of AChE activity. However, the effect of decursin on breast cancer invasion is unknown. Matrix metalloproteinase-9 (MMP-9) is known to be an important factor for cancer cell invasion. Therefore, in this study, we investigated the inhibitory effect of decursin on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion, as well as the molecular mechanisms involved in MCF-7 cells. Our results showed that decursin inhibits TPA-induced MMP-9 expression and cell invasion through the suppression of NF-κB. Furthermore, decursin repressed the TPA-induced phosphorylation of p38 MAPK and inhibited TPA-induced translocation of PKCα from the cytosol to the membrane, but did not affect the translocation of PKCδ. These results indicate that decursin-mediated inhibition of TPA-induced MMP-9 expression and cell invasion involves the suppression of the PKCα, MAPK and NF-κB pathways in MCF-7 cells. Thus, decursin may have potential value in restricting breast cancer metastasis.

Telomerase governs immunomodulatory properties of mesenchymal stem cells by regulating FAS ligand expression.

Bone marrow mesenchymal stem cells (BMMSCs) are capable of differentiating into multiple cell types and regulating immune cell response. However, the mechanisms that govern the immunomodulatory properties of BMMSCs are still not fully elucidated. Here we show that telomerase-deficient BMMSCs lose their capacity to inhibit T cells and ameliorate the disease phenotype in systemic sclerosis mice. Restoration of telomerase activity by telomerase reverse transcriptase (TERT) transfection in TERT(-/-) BMMSCs rescues their immunomodulatory functions. Mechanistically, we reveal that TERT, combined with ß-catenin and BRG1, serves as a transcriptional complex, which binds the FAS ligand (FASL) promoter to upregulate FASL expression, leading to an elevated immunomodulatory function. To test the translational value of these findings in the context of potential clinical therapy, we used aspirin treatment to upregulate telomerase activity in BMMSCs, and found a significant improvement in the immunomodulatory capacity of BMMSCs. Taken together, these findings identify a previously unrecognized role of TERT in improving the immunomodulatory capacity of BMMSCs, suggesting that aspirin treatment is a practical approach to significantly reduce cell dosage in BMMSC-based immunotherapies.

Antibacterial Activity of Rhus javanica against Methicillin-Resistant Staphylococcus aureus.

In the present study, the leaves of Rhus javanica (R. javanica) were extracted with ethanol, and we investigated the antimicrobial activity of the ethanol extract of R. javanica against methicillin-resistant Staphylococcus aureus (MRSA). Control groups were treated with media containing 0.1% DMSO. The ethanol extract of R. javanica inhibited the growth of MRSA at concentrations ranging from 0.05 to 0.2 mg/mL and inhibited acid production at concentrations higher than 0.1 mg/mL (P < 0.05). MRSA biofilm formation was determined by scanning electron microscopy and safranin staining. The ethanol extract of R. javanica inhibited the formation of MRSA biofilms at concentrations higher than 0.05 mg/mL. In confocal laser scanning microscopy, high concentration (0.4-1.6 mg/mL) of R. javanica extract showed bactericidal effect in a dose-dependent manner. In real-time PCR analysis, R. javanica extract showed the inhibition of the genetic expression of virulence factors such as mecA, sea, agrA, and sarA in MRSA. Preliminary phytochemical analysis revealed the strong presence of phenolics. These results suggest that R. javanica may be a useful medicinal plant for inhibiting MRSA, which may be related to the presence of phenolics in the R. javanica extract.

Ethanol Extract of Ulmus pumila Root Bark Inhibits Clinically Isolated Antibiotic-Resistant Bacteria.

In this study, root bark of Ulmus pumila (U. pumila) was extracted with ethanol, and then the antimicrobial effects were tested on clinically isolated 12 MRSA strains and 1 standard MRSA strain. U. pumila showed antibacterial activities against all MRSA strains. Minimum inhibitory concentration (MIC) of U. pumila root bark against all MRSA strains revealed a range from 125 to 250 µ g/mL. These results may provide the scientific basis on which U. pumila root bark has traditionally been used against infectious diseases in Korea. In real-time PCR analysis, the sub-MIC (64-125 µ g/mL) concentrations of U. pumila root bark extract showed the inhibition of the genetic expressions of virulence factors such as mecA, sea, agrA, and sarA in standard MRSA. Phytochemical analyses of U. pumila root bark showed relatively strong presence of phenolics, steroids, and terpenoids. These results suggest that the ethanol extract of U. pumila root bark may have antibacterial activity against MRSA, which may be related to the phytochemicals such as phenolics, steroids, and terpenoids. Further studies are needed to determine the active constituents of U. pumila root bark responsible for such biomolecular activities.

Dihydroavenanthramide D prevents UV-irradiated generation of reactive oxygen species and expression of matrix metalloproteinase-1 and -3 in human dermal fibroblasts.

Ultraviolet B (UVB) radiation induces photoageing by upregulating the expression of matrix metalloproteinases (MMPs) in human skin cells. Dihydroavenanthramide D (DHAvD) is a synthetic analog to naturally occurring avenanthramide, which is the active component in oats. Although anti-inflammatory, anti-atherosclerotic and antioxidant effects have been reported, the antiphotoageing effects of DHAvD are yet to be understood. In this study, we investigated the inhibitory effects of DHAvD on UVB-induced production of reactive oxygen species (ROS) and expression of MMPs, and its molecular mechanism in UVB-irradiated human dermal fibroblasts. Western blot and real-time PCR analyses revealed that DHAvD inhibited UVB-induced MMP-1 and MMP-3 expression. It also significantly blocked UVB-induced ROS generation in fibroblasts. Additionally, DHAvD attenuated UVB-induced phosphorylation of MAPKs, activation of NF-κB and AP-1. DHAvD regulates UVB-irradiated MMP expression by inhibiting ROS-mediated MAPK/NF-κB and AP-1 activation. DHAvD may be a useful candidate for preventing UV light-induced skin photoageing.