Cocoa polyphenols suppress TNF-α-induced vascular endothelial growth factor expression by inhibiting phosphoinositide 3-kinase (PI3K) and mitogen-activated protein kinase kinase-1 (MEK1) activities in mouse epidermal cells

Cocoa polyphenols have antioxidant and anti-inflammatory effects. TNF-α is a pro-inflammatory cytokine that has a vital role in the pathogenesis of inflammatory diseases such as cancer and psoriasis. Vascular endothelial growth factor (VEGF) expression is associated with tumorigenesis, CVD, rheumatoid arthritis and psoriasis. We tested whether cocoa polyphenol extract (CPE) inhibited TNF-α-induced VEGF expression in promotion-sensitive JB6 mouse epidermal cells. CPE significantly inhibited TNF-α-induced up-regulation of VEGF via reducing TNF-α-induced activation of the nuclear transcription factors activator protein-1 (AP-1) and NF-κB, which are key regulators of VEGF expression. CPE also inhibited TNF-α-induced phosphorylation of protein kinase B (Akt) and extracellular signal-regulated kinase. CPE blocked activation of their downstream kinases, p70 kDa ribosomal protein S6 kinase and p90 kDa ribosomal protein S6 kinase. CPE suppressed phosphoinositide 3-kinase (PI3K) activity via binding PI3K directly. CPE did not affect TNF-α-induced phosphorylation of mitogen-activated protein kinase kinase-1 (MEK1) but suppressed TNF-α-induced MEK1 activity. Collectively, these results indicate that CPE reduced TNF-α-induced up-regulation of VEGF by directly inhibiting PI3K and MEK1 activities, which may contribute to its chemopreventive potentia

Quercetin, the active phenolic component in kiwifruit, prevents hydrogen peroxide-induced inhibition of gap-junction intercellular communication

We evaluated the effects of the two main kiwifruit cultivars (gold kiwifruit (GOK) and green kiwifruit (GRK)) and their active phenolic compound, quercetin, on H2O2-induced inhibition of gap-junction intercellular communication (GJIC) in WB-F344 rat liver epithelial cells. We found that both GOK and GRK protect WB-F344 cells from H2O2-induced inhibition of GJIC. The extracellular signal-regulated protein kinase 1/2 (ERK1/2)-connexin 43 (Cx43) signalling pathway is crucial for the regulation of GJIC, and both GOK and GRK blocked the H2O2-induced phosphorylation of Cx43 and ERK1/2 in WB-F344 cells. Quercetin alone attenuated the H2O2-mediated ERK1/2-Cx43 signalling pathway and consequently reversed H2O2-mediated inhibition of GJIC in WB-F344 cells. A free radical-scavenging assay using 1,1-diphenyl-2-picrylhydrazyl showed that the scavenging activity of quercetin was higher than that of a synthetic antioxidant, butylated hydroxytoluene, per mol, suggesting that the chemopreventive effect of quercetin on H2O2-mediated inhibition of ERK1/2-Cx43 signalling and GJIC may be mediated through its free radical-scavenging activity. Since the carcinogenicity of reactive oxygen species such as H2O2 is attributable to the inhibition of GJIC, GOK, GRK and quercetin may have chemopreventive potential by preventing the inhibition of GJI

Effectiveness of p-dopants in an organic hole transporting material

We investigated the effectiveness of p-dopants to generate holes in a hole transporting material by comparing the absorption in visible-near-infrared and infrared regions and current density-voltage characteristics. CuI, MoO3, and ReO3 having different work functions were doped in a hole transporting organic material, 4,4,4-tris(N-(2-naphthyl)-N-phenylamino)-triphenylamine (2TNATA). Formation of charge transfer (CT) complexes increases linearly with increasing doping concentration for all the dopants. Dopants with higher work function (ReO3>MoO3>CuI) are more effective in the formation of CT complexes and in the generation of the charges in the doped films.The authors are grateful to the Ministry of Knowledge Economy MOKE of Korea for financial support of this work. This work was also partially supported by the Samsung SDI and Dongwoo Finechem Co

Microbial Ecology of Watery Kimchi

© 2015 Institute of Food Technologists®. This article has been contributed by US Government employees and their work is in the public domain in the USA. The biochemistry and microbial ecology of 2 similar types of watery (mul) kimchi, containing sliced and unsliced radish and vegetables (nabak and dongchimi, respectively), were investigated. Samples from kimchi were fermented at 4, 10, and 20 °C were analyzed by plating on differential and selective media, high-performance liquid chromatography, and high-throughput DNA sequencing of 16S rDNA. Nabak kimchi showed similar trends as dongchimi, with increasing lactic and acetic acids and decreasing pH for each temperature, but differences in microbiota were apparent. Interestingly, bacteria from the Proteobacterium phylum, including Enterobacteriaceae, decreased more rapidly during fermentation at 4 °C in nabak cabbage fermentations compared with dongchimi. Although changes for Proteobacterium and Enterobacteriaceae populations were similar during fermentation at 10 and 20 °C, the homolactic stage of fermentation did not develop for the 4 and 10 °C samples of both nabak and dongchimi during the experiment. These data show the differences in biochemistry and microbial ecology that can result from preparation method and fermentation conditions of the kimchi, which may impact safety (Enterobacteriaceae populations may include pathogenic bacteria) and quality (homolactic fermentation can be undesirable, if too much acid is produced) of the product. In addition, the data also illustrate the need for improved methods for identifying and differentiating closely related lactic acid bacteria species using high-throughput sequencing methods.This work was carried out as part of the international collaborative R&D program funded by the Agency for Korea Natl. Food Cluster (2013), and supported in part by a grant from Pickle Packers Intl. Inc., Washington, D.C., U.S.A. The authors thank the Spanish Government (MECD) for the postdoctoral fellowship support for Dr. E. Medina-Pradas.Peer Reviewe

Primary Esophageal Mucosa-associated Lymphoid Tissue Lymphoma: A Rare Case Report and Review of Other Published Data

The gastrointestinal tract is the most common extranodal site for lymphomas, and mucosa-associated lymphoid tissue lymphoma is the second most common histological lymphoma subtype. However, primary esophageal mucosa-associated lymphoid tissue lymphomas are extremely rare. Few such cases are documented, and the reports demonstrate inconsistent diagnostic and therapeutic strategies. Herein, a 54-year-old man was referred to our hospital for treatment of dysphagia. Esophagogastroduodenoscopy revealed a large, horseshoe-shaped subepithelial mass in the upper esophagus. Endoscopic ultrasonography and computed tomography revealed that the mass was well-demarcated and confined to the muscularis mucosa, with no abnormalities in other organs or lymph nodes. The mass was presumptively diagnosed as benign, and the patient underwent endoscopic mucosal dissection for pathological confirmation and symptom relief. Pathological examination of the dissection specimen revealed that it was a primary esophageal mucosa-associated lymphoid tissue lymphoma. As the patient had an elevated immunoglobulin G level and Helicobacter pylori infection, we administered adjuvant eradication therapy. The patient remains under surveillance and is free of lymphoma recurrence 36 months postoperatively. This case report demonstrates that endoscopic resection and H. pylori eradication are effective treatment strategies for early-stage esophageal mucosa-associated lymphoid tissue lymphoma

Immunogenicity and Safety of Trivalent Inactivated Influenza Vaccine: A Randomized, Double-Blind, Multi-Center, Phase 3 Clinical Trial in a Vaccine-Limited Country

Influenza vaccines are the primary method for controlling influenza and its complications. This study was conducted as a phase 3, randomized, double-blind, controlled, multi-center trial at seven university hospitals to evaluate the immunogenicity and safety of an inactivated, split, trivalent influenza vaccine (GC501, Green Cross Corporation, Yongin, Korea), which was newly manufactured in Korea in 2008. Between September 21 and 26, a total of 329 healthy subjects were recruited for the immunogenicity analysis, while 976 subjects were enrolled for the safety analysis. The GC501 vaccine met both FDA and EMEA criteria with ≥ 80% of subjects achieving post-vaccination titers ≥ 40 for all three subtypes, even in the elderly. The vaccine was well tolerated with only mild systemic and local adverse events. In summary, GC501 showed excellent immunogenicity and a good safety profile in both young adults and the elderly. The licensure of GC501 might be an important basis in preparation for the future influenza pandemic

Vitamin C and cancer chemoprevention: Reappraisal

Several studies have reported that even a moderate daily dose of supplementary vitamin C (200 mg) induces the formation of genotoxins from lipid hydroperoxides, thereby resulting in DNA damage and initiation of carcinogenesis. However, other reports questioned the experimental designs used and suggested that the chemopreventive effects of vitamin C may be linked to the inhibition of tumor promotion as well as to the blocking of tumor initiation. In this article, we discuss issues of contention and some controversies related to the potential chemopreventive effects of vitamin C in carcinogenesis

Curcumin inhibits phorbol ester-induced up-regulation of cyclooxygenase-2 and matrix metalloproteinase-9 by blocking ERK1/2 phosphorylation and NF-kappa B transcriptional activity in MCF10A human breast epithelial cells

Elevated levels of cyclooxgenase-2 (COX-2) and matrix metalloproteinases (NMPs) are often observed in various types of cancerous and transformed cells, and hence recognized as potential molecular targets for the chemoprevention. In the present study, we investigated the possible inhibitory effects of curcumin on the expression of COX-2 and MMP-9 induced by the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA) in MCF10A human breast epithelial (MCF10A) cells and the underlying mechanisms. Curcumin inhibited the TPA-induced COX-2 expression at both transcriptional and post-transcriptional levels, and reduced the synthesis of prostaglandin E 25 one of the major products of COX-2. Likewise, curcumin attenuated invasiveness and motility of MCF10A cells stimulated with TPA through suppression of MNIP expression. Curcumin blocked TPA-induced activation of extracellular signal-regulated protein kinase (ERK1/2) and nuclear factor kappa B (NF-kappa B) transcriptional activity. Overexpression of the dominant negative forms of ERK2 abrogated the TPA-induced NF-kappa B transcriptional activity. Treatment of MCF10A cells with U0126, which is a pharmacological inhibitor of ERK1/2, reduced TPA-induced up-regulation of COX-2 and NMP-9. Taken together, these findings suggest that curcumin inhibits the TPA-induced up-regulation of COX-2 and MMP-9 by suppressing ERK1/2 phosphorylation and NF-kappa B trans-activation in human breast epithelial cells, which may contribute to its chemopreventive potential