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Quercetin is a flavonoid polyphenolic compound present in fruits and vegetables that has proven anti-inflammatory activity. The goal of the present investigation was to investigate the effects of quercetin on tumor necrosis factor-α (TNF-α)-induced inflammatory responses via the expression of ICAM-1 and MMP-9 in human retinal pigment epithelial cells (ARPE-19 cells). Real-time PCR, gelatin zymography, and Western blot analysis showed that TNF-α induced the expression of ICAM-1 and MMP-9 protein and mRNA in a time-dependent manner. These effects were attenuated by pretreatment of ARPE-19 cells with quercetin. Quercetin inhibited the TNF-α-induced phosphorylation of PKCδ, JNK1/2, ERK1/2. Quercetin, rottlerin, SP600125 and U0126 attenuated TNF-α-stimulated c-Jun phosphorylation and AP-1-Luc activity. Pretreatment with quercetin, rottlerin, SP600125, or Bay 11-7082 attenuated TNF-α-induced NF-κB (p65) phosphorylation, translocation and RelA/p65-Luc activity. TNF-α significantly increased MMP-9 promoter activity and THP-1 cell adherence, and these effects were attenuated by pretreatment with quercetin, rottlerin, SP600125, U0126, tanshinone IIA or Bay 11-7082. These results suggest that quercetin attenuates TNF-α-induced ICAM-1 and MMP-9 expression in ARPE-19 cells via the MEK1/2-ERK1/2 and PKCδ-JNK1/2-c-Jun or NF-κB pathways.

Introduction Resveratrol has been reported to alleviate inflammatory responses and oxidative stress in mesangial cells and in several types of renal injury in animal models. Previously, the active resveratrol derivatives from the roots of Vitis thunbergii Sieb. & Zucc. (Vitaceae) were shown to have significant anti-platelet and anti-oxidative activities. However, the anti-inflammatory mechanisms of these resveratrol derivatives in rat mesangial cells (RMCs) have not been clarified fully. Methods The protective mechanisms of resveratrol derivatives involved in tumor necrosis factor-α (TNF-α)-induced inflammatory responses were assessed by Western blot analysis, real-time PCR, and RT–PCR. The involvement of various signaling molecules in these responses was investigated using selective pharmacological inhibitors. Results Nontoxic concentrations of the resveratrol derivatives significantly attenuated cytosolic phospholipase A2 (cPLA2) and cyclooxygenase 2 (COX-2) expression in RMCs challenged by TNF-α. These resveratrol derivatives inhibited TNF-α-activated ERK1/2 and JNK1/2 without affecting p38 phosphorylation. Next, we demonstrated that TNF-α induced NF-κB activation, translocation, and promoter activity, which was inhibited by pretreatment with resveratrol derivatives in RMCs. Conclusion The protective mechanisms of resveratrol derivatives against TNF-α-stimulated inflammatory responses via cPLA2/COX-2/PGE2 inhibition was caused by the attenuation of the JNK1/2, ERK1/2, and NF-κB signaling pathways in RMCs.

Staphylococcus aureus (S. aureus) can lead to many life-threatening diseases. It has the ability to invade normal endovascular tissue. The molecular mechanisms and pathological changes of endothelial cells after S. aureus infection are of interest, but the basic understanding of how S. aureus destroys this barrier is not clear. Here, we showed that S. aureus enhanced COX-2 expression and prostaglandin E2 (PGE2) secretion in human aortic endothelial cells (HAECs). In addition, S. aureus induced PGE2/interleukin-6 (IL-6)/matrix metallopeptidase-9 (MMP-9)-dependent cell migration. S. aureus-induced COX-2, IL-6, and MMP-9 levels were inhibited by transfection with siRNA of Toll-like receptor 2 (TLR2), p38, p42, p44, p50, or p65. S. aureus also induced p38 MAPK, ATF2, ERK1/2, and NF-κB p65 activation. Interestingly, we proved that S. aureus decreased intracellular generation of reactive oxygen species (ROS), which suggests that the inhibition of ROS production promoted inflammatory responses. Finally, we showed that S. aureus enhanced a variety of biomarkers of inflammation in cardiovascular diseases. However, the free radical scavenger (MCI-186) or antioxidant (N-acetyl-L-cysteine, NAC) markedly enhanced S. aureus-induced COX-2 mRNA levels in the aorta tissues. Taken together, these findings established that S. aureus promoted aorta inflammation via activation of p38 MAPK, ERK1/2, and NF-κB and inhibition of ROS generation.

Objectives To modify a chitosan membrane (CM) by cross-linking the chitosan with genipin, a naturally occurring cross-linker extracted from Gardenia jasminoides fructus, with the aim of developing a new cell culture support and to observe the phenotypes of cultured human corneal epithelial cells (HCECs) on genipin-cross-linked chitosan membrane (GCM). Methods We tested the cross-linking characteristics and mechanical strength of the GCM. CMs modified by cross-linking with different concentrations of genipin were prepared to investigate the rate of membrane degradation. The biocompatibility of the GCMs was investigated by determining the viability of HCECs cultured on them in vitro. The morphology of the HCECs cultured on CM or GCM was analyzed by confocal microscopy and scanning electron microscopy (SEM). Immunocytochemical staining was conducted to determine the phenotypes of the cultured cells. Results The fixation index of the GCM was 31 ± 3% after treatment of CM with 0.5 mM genipin. A stress–strain test showed that the GCM could tolerate three times the mechanical force of noncross-linked CM. The biodegradation rate of GCM was much slower than for CM. A 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay showed that cell viability was not affected by cross-linking with 5.0 mM genipin. SEM showed that the cultured HCECs adhered to and grew well on the surface of the GCM. Immunocytochemical staining showed keratin 3 (K3) and connexin 43 (Cx-43) immunoreactive HCECs on the GCM and their proliferative ability was not significantly affected by strong immunoreactivity of Ki-67 and p63 markers. Conclusions GCM has potential as a scaffold for corneal epithelium in ocular surface surgery and greater mechanical strength and slower degradation than unmodified CM.

Matrix metalloproteinase-9 (MMP-9) plays an important role in the outgrowth of expanded human limbal epithelial cells on intact amniotic membranes (AM). The mechanisms of MMP-9 expression and cell outgrowth remain unknown. Here, we demonstrated that MMP-9 is preferentially expressed at the leading edge of limbal epithelial outgrowth. Treatment with the inhibitors of PI3-K (LY294002), Akt (SH-5), MEK1/2 (U0126), and JNK1/2 (SP600125) attenuated the outgrowth area, indicating that PI3-K/Akt, p42/p44 MAPK, and JNK1/2 are involved in the outgrowth of intact AM-expanded limbal epithelial cells. However, MMP-9 expression at both transcriptional and translational levels was attenuated by treatment with SP600125, LY294002, or SH-5, not by U0126 and SB202190, suggesting that JNK1/2 and PI3-K/Akt participate in MMP-9 expression. Moreover, NF-κB phosphorylation and nuclear translocation was especially noted at the leading edge, which was attenuated by treatment with SP600125 or LY294002. Helenalin, a selective NF-κB inhibitor, reduced both the limbal epithelial outgrowth and MMP-9 expression. Finally, the data reveal that PI3-K/Akt is an upstream component of the JNK1/2 pathway in MMP-9 expression. Thus, both MAPKs and PI3-K/Akt are required for limbal epithelial outgrowth on intact AM, only the PI3-K/Akt/JNK is essential for MMP-9 expression mediated through activation of transcriptional factor NF-κB in this model.

Nano Pd–Au particles have been electrochemically fabricated utilizing ionic liquid as green electrolyte (1-Butyl-3-methylimidazolium tetrafluoroborate). Nano Pd–Au particles modified glassy carbon electrode (GCE) and indium tin oxide coated glass electrodes were examined using atomic force microscopy, field emission scanning electron microscope and X-ray diffraction studies. Electrodeposited nano Pd–Au particles' average diameter was found as 33 nm. Nano Pd–Au particle modified GCE was electrochemically active and stable in various pH solutions. The proposed nano particle modified GCE reduces the over potential and shows the well defined oxidation peaks for the detection of epinephrine and simultaneous determination of dopamine and uric acid (in pH 7.0 phosphate buffer solution) using cyclic voltammetry and differential pulse voltammetry.

Matrix metalloproteinases (MMPs), in particular MMP-9, is induced by cytokines including IL-1 beta and contributes to airway injury and remodeling. However, the mechanisms underlying IL-1 beta-induced MMP-9 expression and cell migration in human A549 cells remain unclear. Here, we report that the IL-1 beta-induced MMP-9 gene expression was mediated through the activation of p42/p44 MAPK, p38 MAPK, and JNK1/2 in A549 cells, determined by zymographic, RT-PCR, and Western blotting. The involvement of MAPKs in the IL-1beta-induced responses was further ensured by transfection with siRNA of MEK1, p42, p38, or JNK2. Moreover, the IL-1 beta-induced MMP-9 gene expression was also mediated through the translocation of NF-kappaB (p65) into the nucleus and the degradation of I kappaB alpha. In addition, the IL-1 beta-induced c-Jun phosphorylation was reduced by pretreatment with U0126 or SP600125. IL-1 beta stimulated the transcriptional activity of wild-type MMP-9 promoter in A549 cells, which was inhibited by U0126, SB203580, SP600125, and helenalin. In contrast, IL-1 beta had no effect on the cells transfected with a NF-kappaB-mutated MMP-9 promoter construct, suggesting that NF-kappaB is required for this response. Finally, the IL-1 beta-induced MMP-9 expression led to cell migration which was attenuated by pretreatment with U0126, SB203580, SP600125, helenalin, or MMP-2/9 inhibitor. These results suggested that in A549 cells, the activation of p42/p44 MAPK, p38 MAPK, JNK1/2, NF-kappaB, and AP-1 are essential for the IL-1 beta-induced MMP-9 gene expression and cell migration.

Matrix metalloproteinases (MMPs), in particular MMP-9, have been shown to be induced by cytokines including tumor necrosis factor-alpha (TNF-alpha) and contributes to airway inflammation. However, the mechanisms underlying MMP-9 expression induced by TNF-alpha in human A549 cells remain unclear. Here, we showed that TNF-alpha induced production of MMP-9 protein and mRNA is determined by zymographic, Western blotting, RT-PCR and ELISA assay, which were attenuated by inhibitors of MEK1/2 (U0126), JNK (SP600125), and NF-kappaB (helenalin), and transfection with dominant negative mutants of ERK2 (DeltaERK) and JNK (DeltaJNK), and siRNAs for MEK1, p42 and JNK2. TNF-alpha-stimulated phosphorylation of p42/p44 MAPK and JNK were attenuated by pretreatment with the inhibitors U0126 and SP600125 or transfection with dominant negative mutants of DeltaERK and DeltaJNK. Furthermore, the involvement of NF-kappaB in TNF-alpha-induced MMP-9 production was consistent with that TNF-alpha-stimulated degradation of IkappaB-alpha and translocation of NF-kappaB into the nucleus which were blocked by helenalin, but not by U0126 and SP600125, revealed by immunofluorescence staining. The regulation of MMP-9 gene transcription by MAPKs and NF-kappaB was further confirmed by gene luciferase activity assay. MMP-9 promoter activity was enhanced by TNF-alpha in A549 cells transfected with wild-type MMP-9-Luc, which was inhibited by helenalin, U0126, or SP600125. In contrast, TNF-alpha-stimulated MMP-9 luciferase activity was totally lost in cells transfected with mutant-NF-kappaB MMP-9-luc. Moreover, pretreatment with actinomycin D and cycloheximide attenuated TNF-alpha-induced MMP-9 expression. These results suggest that in A549 cells, phosphorylation of p42/p44 MAPK, JNK, and transactivation of NF-kappaB are essential for TNF-alpha-induced MMP-9 gene expression.

This paper illustrates applications of the Web-based collaborative visualization (WCV) in distributed product development. Three software prototypes were developed using the WCV technologies. The first one enables the end users to configure individual parts of 3D assembly in a regular browser, and thus provides an effective tool to collect the customer's voices in e-commerce. The second system realizes mass customization for car interior design. Online ergonomic evaluation is conducted based on the interactions between a digital human mimicking the user and the design model. Finally, an Internet-based design review system is implemented. It enables synchronous communications between a designer and people involved in the change process with no access to CAD. These prototypes demonstrate the practicality, flexibility, and versatility of the WCV in integration with other proprietary software tools using a variety of platforms like ASP framework, Java-based technology, and Windows C/C++ applications. This work shows that the WCV is an interfacing technology, which facilitates 3D information sharing for most product-centric activities in a simple and cost-effective manner.

The importance of the Bcl-2 family proteins in normal vertebrate embryogenesis is being recognized; however, their regulatory mechanism is poorly understood. We report here the cloning and characterization of a novel zebrafish Bcl-2 family protein, zfBLP1. The zfBLP1 cDNA is 1942 nucleotides long, encoding a polypeptide of 238 amino acids. The primary sequence of zfBLP1 shares 50% identity to human Bcl-XL, and contains all four conserved BH domains of the Bcl-2 family proteins. Primary sequence analysis identified a consensus ER retention signal at the C-terminal end of zfBLP1. Northern blot analysis indicated that there were two major and two minor zfBLP1 mRNA species expressed during embryonic development. Among the two major mRNA species, the short one, approx. 3 kb in size, was expressed throughout embryonic development, while the long one, approx. 7 kb long, was not detectable until the gastrula stage. These results suggest that zfBLP1 is a novel Bcl-2 family protein under complicated regulations, and is likely to play an important role in zebrafish oogenesis and embryogenesis.