Emergence of Norovirus GII.17-associated Outbreak and Sporadic Cases in Korea from 2014 to 2015.

Human norovirus are major causative agent of nonbacterial acute gastroenteritis. In general, genogroup (G) II.4 is the most prominent major genotype that circulate in human population and the environment. However, a shift in genotypic trends was observed in Korea in December 2014. In this study, we investigated the trend of norovirus genotype in detail using the database of Acute Diarrhea Laboratory Surveillance (K-EnterNet) in Korea. GII.17 has since become a major contributor to outbreaks of norovirus-related infections and sporadic cases in Korea, although the reason for this shift remain unknown.

Epidemics of Norovirus GII.4 Variant in Outbreak Cases in Korea, 2004-2012.

Norovirus GII.4 is recognized as a worldwide cause of nonbacterial outbreaks. In particular, the GII.4 variant occurs every 2-3 years according to antigenic variation. The aim of our study was to identify GII.4 variants in outbreaks in Korea during 2004-2012. Partial VP1 sequence of norovirus GII.4-related outbreaks during 2004-2012 was analyzed. The partial VP1 sequence was detected with reverse transcription-polymerase chain reaction, seminested polymerase chain reaction, and nucleotide sequence of 312-314 base pairs for phylogenetic comparison. Nine variants emerged in outbreaks, with the Sydney variant showing predominance recently. This predominance may persist for at least 3 years, although new variants may appear in Korea.

Occurrence of Norovirus GII.4 Sydney Variant-related Outbreaks in Korea.

Human noroviruses are major causative agents of food and waterborne outbreaks of nonbacterial acute gastroenteritis. In this study, we report the epidemiological features of three outbreak cases of norovirus in Korea, and we describe the clinical symptoms and distribution of the causative genotypes. The incidence rates of the three outbreaks were 16.24% (326/2,007), 4.1% (27/656), and 16.8% (36/214), respectively. The patients in these three outbreaks were affected by acute gastroenteritis. These schools were provided unheated food from the same manufacturing company. Two genotypes (GII.3 and GII.4) of the norovirus were detected in these cases. Among them, major causative strains of GII.4 (Hu-jeju-47-2007KR-like) were identified in patients, food handlers, and groundwater from the manufacturing company of the unheated food. In the GII.4 (Hu-jeju-47-2007KR-like) strain of the norovirus, the nucleotide sequences were identical and identified as the GII.4 Sydney variant. Our data suggests that the combined epidemiological and laboratory results were closely related, and the causative pathogen was the GII.4 Sydney variant strain from contaminated groundwater.

Protein tyrosine phosphatase controls breast cancer invasion through the expression of matrix metalloproteinase-9.

The expression of matrix metalloproteinases (MMPs) produced by cancer cells has been associated with the high potential of metastasis in several human carcinomas, including breast cancer. Several pieces of evidence demonstrate that protein tyrosine phosphatases (PTP) have functions that promote cell migration and metastasis in breast cancer. We analyzed whether PTP inhibitor might control breast cancer invasion through MMP expression. Herein, we investigate the effect of 4-hydroxy-3,3-dimethyl-2H benzo[g]indole-2,5(3H)-dione (BVT948), a novel PTP inhibitor, on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion in MCF-7 cells. The expression of MMP-9 and cell invasion increased after TPA treatment, whereas TPA-induced MMP-9 expression and cell invasion were decreased by BVT948 pretreatment. Also, BVT948 suppressed NF-κB activation in TPA-treated MCF-7 cells. However, BVT948 didn't block TPA-induced AP-1 activation in MCF-7 cells. Our results suggest that the PTP inhibitor blocks breast cancer invasion via suppression of the expression of MMP-9.

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.

Emodin suppresses inflammatory responses and joint destruction in collagen-induced arthritic mice.

OBJECTIVE: Emodin (3-methyl-1,6,8-trihydroxyanthraquinone) is one of the active components present in the root and rhizome of Rheum palmatum. It has been shown to contain biological activity (antitumour, antibacterial, diuretic and vasorelaxant effects). However, the mechanisms underlying the anti-arthritic effect of emodin have not been elucidated. Here we investigated whether emodin treatment would modulate the severity of the disease in an experimental arthritis model. METHODS: We evaluated the effects of emodin on CIA mice in vivo. RESULTS: The pathological processes of RA are mediated by a number of cytokines and MMPs. Expression of these proinflammatory mediators is controlled by nuclear factor-κB (NF-κB). This study was performed to explore the effect of emodin on control of the NF-κB activation pathway and to investigate whether emodin has anti-inflammatory effects in CIA mice in vivo. Emodin inhibited the nuclear translocation and DNA binding of NF-κB subunits, which were correlated with its inhibitory effect on cytoplasmic IκBα degradation in CIA mice. These events further suppressed chemokine production and MMP expression. In addition, emodin inhibited the osteoclast differentiation induced by M-CSF and receptor activation of NF-κB ligand in bone marrow macrophages. CONCLUSION: These findings suggest that emodin exerts anti-inflammatory effects in CIA mice through inhibition of the NF-κB pathway and therefore may have therapeutic value for the treatment of RA.

Curcumin inhibits UVB-induced matrix metalloproteinase-1/3 expression by suppressing the MAPK-p38/JNK pathways in human dermal fibroblasts.

Curcumin (diferuloylmethane) is a polyphenol derived from turmeric (Curcuma longa), which is commonly used as a spice. Recent studies have shown that curcumin has a wide range of pharmacological activities, including anticarcinogenic, antioxidant, anti-inflammatory and antiangiogenic activities. However, the antiphotoageing effects of curcumin have yet to be characterized. In this study, we investigated the inhibitory effects of curcumin on matrix metalloproteinase (MMP)-1 and MMP-3 expression in human dermal fibroblast cells. Western blot analysis revealed that curcumin inhibited ultraviolet (UV) B-induced MMP-1 and MMP-3 expression. Furthermore, curcumin significantly blocked UVB-induced reactive oxygen species generation in fibroblasts. Curcumin treatment significantly blocked the UVB-induced activation of nuclear factor (NF)-κB and activator protein (AP)-1. Additionally, curcumin strongly repressed the UVB-induced phosphorylation of p38 and c-Jun N-terminal kinase. Curcumin prevented UVB-induced MMP expression through mitogen-activated protein kinase/NF-κB inhibition and AP-1 activation. In conclusion, curcumin may be useful for preventing and treating skin photoageing.

Sulforaphane controls TPA-induced MMP-9 expression through the NF-κB signaling pathway, but not AP-1, in MCF-7 breast cancer cells.

Sulforaphane [1-isothiocyanato-4-(methylsulfinyl)-butane] is an isothiocyanate found in some cruciferous vegetables, especially broccoli. Sulforaphane has been shown to display anti-cancer properties against various cancer cell lines. Matrix metalloproteinase-9 (MMP-9), which degrades the extracellular matrix (ECM), plays an important role in cancer cell invasion. In this study, we investigated the effect of sulforaphane on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion in MCF-7 cells. TPA-induced MMP-9 expression and cell invasion were decreased by sulforaphane treatment. TPA substantially increased NF-κB and AP-1 DNA binding activity. Pre-treatment with sulforaphane inhibited TPA-stimulated NF-κB binding activity, but not AP-1 binding activity. In addition, we found that sulforaphane suppressed NF-κB activation, by inhibiting phosphorylation of IκB in TPA-treated MCF-7 cells. In this study, we demonstrated that the inhibition of TPA-induced MMP-9 expression and cell invasion by sulforaphane was mediated by the suppression of the NF-κB pathway in MCF-7 cells.

Suppression of TPA-induced tumor cell invasion by sulfuretin via inhibition of NF-κB-dependent MMP-9 expression.

Cell invasion is required for neoplastic metastasis. Matrix metalloproteinase-9 (MMP-9), which degrades the extracellular matrix, is a major component in the process of cancer cell invasion. Sulfuretin is one of the major flavonoids isolated from Rhus verniciflua. Sulfuretin has been used to reduce oxidative stress, platelet aggregation, the inflammatory response and mutagenesis. However, the effect of sulfuretin on breast cancer metastasis is unknown. In this study, we investigated the inhibitory effect of sulfuretin on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion in MCF-7 cells. Sulfuretin inhibited TPA-induced transcriptional activation of nuclear factor-κB (NF-κB). We demonstrated that sulfuretin mediated the inhibition of TPA-induced MMP-9 expression and that cell invasion in MCF-7 cells involved suppression of the NF-κB pathway. Therefore, inhibiting MMP-9 expression by sulfuretin may have therapeutic potential for controlling breast cancer invasiveness.

Decursin inhibits UVB-induced MMP expression in human dermal fibroblasts via regulation of nuclear factor-κB.

Decursin, a coumarin compound, was originally isolated from the roots of Angelica gigas almost four decades ago, and it was found to exhibit cytotoxicity against various types of human cancer cells and anti-amnesic activity in vivo through the inhibition of AChE activity. However, the anti-skin photoaging effects of decursin have not been reported to date. In the present study, we investigated the inhibitory effects of decursin on the expression of matrix metalloproteinase (MMP)-1 and MMP-3 in human dermal fibroblast (HDF) cells. Western blot analysis and real-time PCR revealed that decursin inhibited the ultraviolet (UV)B-induced expression of MMP-1 and MMP-3 in a dose-dependent manner. Decursin significantly blocked the UVB-induced activation of nuclear factor-κB (NF-κB). However, decursin showed no effect on MAPK or AP-1 activity. In this study, decursin prevented the UVB-induced expression of MMPs via the inhibition of NF-κB activation. In conclusion, decursin may be a potential agent for the prevention and treatment of skin photoaging.

Curcumin suppresses the TPA-induced invasion through inhibition of PKCα-dependent MMP-expression in MCF-7 human breast cancer cells.

Curcumin (diferuloylmethane) is a polyphenol derived from the plant turmeric (Curcuma longa), which is commonly used as a spice. Although anti-carcinogenic, anti-oxidant, anti-inflammation, and anti-angiogenic properties have been reported, the effect of curcumin on breast cancer metastasis is unknown. Matrix metalloproteinase-9 (MMP-9) is a major component in cancer cell invasion. In this study, we investigated the inhibitory effect of curcumin on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion and the molecular mechanisms involved in MCF-7 cells. Our results showed that curcumin inhibits TPA-induced MMP-9 expression and cell invasion through suppressing NF-κB and AP-1 activation. Also, curcumin strongly repressed the TPA-induced phosphorylation of p38 and JNK 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 curcumin-mediated inhibition of TPA-induced MMP-9 expression and cell invasion involves the suppression of the PKCα, MAPK and NF-κB/AP-1 pathway in MCF-7 cells. Curcumin may have potential value in restricting breast cancer metastasis.

Brazilin inhibits UVB-induced MMP-1/3 expressions and secretions by suppressing the NF-κB pathway in human dermal fibroblasts.

Brazilin (7, 11b-dihydrobenz[b]indeno[1,2-d]pyran-3,6a,9,10 (6H)-tetrol), the major component of Caesalpinia sappan L., is a natural red pigment used for histological staining. Recent studies have shown that brazilin exhibits distinct biological effects, including anti-hepatotoxicity, antiplatelet activity, and anti-inflammatory activities. In the present study, we evaluated the effects of brazilin on MMP-1 and -3 expressions in human dermal fibroblasts exposed to ultraviolet B (UVB) irradiation. Brazilin showed protective effect on UVB-induced loss of cell viability of fibroblasts. Brazilin also blocked significantly UVB-induced Reactive Oxygen Species generation in fibroblasts. Brazilin inhibited UVB-induced MMP-1/3 expressions and secretions in a dose-dependent manner. Moreover, UVB-induced NF-κB activation was completely blocked by treatment with brazilin. These findings suggest that brazilin inhibits UVB-induced MMP-1/3 expressions and secretions by suppressing of NF-κB activation in human dermal fibroblasts. Thus, brazilin might be used as a potential agent for treatment of UV-induced skin photoaging.