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This study was performed to evaluate whether endocan expression, which is known to be involved in tumor angiogenesis, was increased in rheumatoid arthritic tissues. In addition, the involvement of adiponectin in the regulation of endocan expression in arthritic joints was examined. Arthritic synovial tissues from patients with rheumatoid arthritis (RA) or osteoarthritis (OA) were immunostained with antibodies to endocan and vascular endothelial growth factor (VEGF). Subsequently, synovial cells and human umbilical vein endothelial cells were cultured and stimulated with interleukin-1 β (IL-1β) or adiponectin. The mRNA and protein levels of endocan were evaluated by polymerase chain reaction and ELISA, respectively. Endocan expression was markedly increased in the inflammatory sites of RA synovial tissues. In OA tissues, endocan expression was higher in tissues displaying moderate and severe inflammation than in those with mild inflammation. In vitro expression levels of endocan and VEGF in endothelial and synovial cells were differentially increased in response to IL-1β stimulation. Adiponectin was a more potent stimulant of endocan than IL-1β at their respective physiological concentrations in synovial cells. Endocan silencing by small interfering RNA transfection of synovial cells decreased in vitro cell migration and invasion. In conclusion, adiponectin is an important factor in the stimulation of endocan expression in synovial cells. Adiponectin-induced endocan expression in synovial cells may stimulate cell migration and invasion as well as angiogenesis in the pannus of arthritic joints.

In pig-to-primate xenotransplantation, multiple transgenic pigs are required to overcome a series of transplant rejections. The generation of multiple transgenic pigs either by breeding or the introduction of several mono-cistronic vectors has been hampered by the differential expression patterns of the target genes. To achieve simultaneous expression of multiple genes, a poly-cistronic expression system using the 2A peptide derived from the Thosea asigna virus (T2A) can be considered an alternative choice. Before applying T2A expression system to pig generation, the expression patterns of multiple genes in this system should be precisely evaluated. In this study, we constructed several bi-cistronic T2A expression vectors, which combine target genes that are frequently used in the xenotransplantation field, and introduced them into porcine fibroblasts. The proteins targeted to the same or different subcellular regions were efficiently expressed without affecting the localization or expression levels of the other protein. However, when a gene with low expression efficiency was inserted into the upstream region of the T2A sequences, the expression level of the downstream gene was significantly decreased compared with the expression efficiency without the insertion. A small interfering RNA targeting one gene in this system resulted in the significant downregulation of both the target gene and the other gene, indicating that multiple genes combined into a T2A expression vector can be considered as a single gene in terms of transcription and translation. In summary, the efficient expression of a downstream gene can be achieved if the expression of the upstream gene is efficient.

Small heat shock proteins are involved in stress tolerance. We previously isolated and characterized a rice cDNA clone, Oshsp26, encoding a chloroplast-localized small heat shock protein that is expressed following oxidative or heat stress. In this study, we transferred this gene to tall fescue plants by an Agrobacterium-mediated transformation system. The integration and expression of the transgene was confirmed by PCR, Southern, northern, and immunoblot analyzes. Compared to the control plants, the transgenic plants had significantly lower electrolyte leakage and accumulation of thiobarbituric acid-reactive substances when exposed to heat or methyl viologen. The photochemical efficiency of photosystem II (PSII) (Fv/Fm) in the transgenic tall fescue plants was higher than that in the control plants during heat stress (42°C). These results suggest that the OsHSP26 protein plays an important role in the protection of PSII during heat and oxidative stress in vivo.

To mitigate the oxidative damage inflicted by biotic or abiotic stresses, plants have evolved complex anti-oxidative defense mechanisms that involve induction of antioxidant and anti-oxidative enzymes, such as superoxide dismutase (SOD) and ascorbate peroxidase (APX). To determine whether overexpression of the genes encoding copper-zinc SOD (CuZnSOD) and APX in plants is capable of decreasing reactive oxygen species (ROS) produced in response to abiotic stresses, we generated transgenic tall fescue plants expressing the CuZnSOD and APX genes in chloroplasts under the control of the oxidative stress-inducible promoter, sweet potato peroxidase anionic 2 (SWPA2). Transgenic plants were generated by Agrobacterium-mediated genetic transformation, and genotypes were confirmed by DNA blot analysis. Transgenic plants were exposed to several ROS-generating abiotic stresses, such as methyl viologen (MV), H(2)O(2), and the heavy metals copper, cadmium, and arsenic, and their tolerance was evaluated. High levels of CuZnSOD and APX gene transcripts in the transgenic plants under these treatments suggested that the transgenes were functionally expressed. Compared to transgenic plants, higher amounts of ROS were generated in the leaves of control plants exposed to abiotic stresses, resulting in increased thiobarbituric acid reactive substances (TBARS), ion leakage, and chlorophyll degradation. These parameters were significantly lower in transgenic plants. Enzyme activity assays and native polyacrylamide gel electrophoresis (PAGE) showed that total SOD and APX were highly active in transgenic plants under the abiotic stresses examined. We conclude that one of the mechanisms of increased anti-oxidative defense in transgenic tall fescue plants is overexpression of the CuZnSOD and APX genes, which are utilized in scavenging ROS and thus provide improved tolerance to abiotic stresses.

Background: Asthma is chronic airway inflammation that occurs together with reversible airway obstruction. T-lymphocytes play an important role in the pathogenesis of asthma. Proteomic technology has rapidly developed in the postgenomic era, and it is now widely accepted as a complementary technology to genetic profiling. We investigated the changes of proteins in T-lymphocytes of asthma patients by using standard proteome technology: two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and a database search., Methods: The proteins of CD3+ T-lymphocytes were isolated from whole blood of six steroid-naive asthmatic patients and of six healthy volunteers. 2D-PAGE was performed and the silver-stained protein spots were comparatively analyzed between the asthma and control groups using an image analyzer. Some differentially expressed spots were identified by MALDI-TOF-MS and database search. The messenger RNA expressions of some identified proteins were examined by real-time polymerase chain reaction (RT-PCR)., Results: Thirteen protein spots in the T-lymphocytes of the asthmatic patients were increased and 12 spots were decreased compared to those of the normal subjects. Among the identified proteins, the increased expression of the messenger RNA of phosphodiesterase 4C and thioredoxin-2 and the decreased expression of the messenger RNA of glutathione S-transferase M3 were confirmed by RT-PCR in the asthmatic patients., Conclusions: Proteomic examination of the peripheral T-lymphocytes revealed some differentially expressed proteins in the asthmatic patients. The possibility of using the differentially expressed proteins as important biomarkers and therapeutic targets in asthma patients warrants further studies.

This study evaluated the antioxidative and anti-inflammatory effects of a low-molecular-weight hydrolysate derived from black goat extract using alcalase, ProteAX, and trypsin (APT6 < 3 kDa). The APT6 < 3 kDa exhibited high antioxidative activities with estimated contents of 41.24% for antioxidative amino acids and 49.55% for hydrophobic amino acids. APT6 < 3 kDa inhibited nitric oxide and prostaglandin E 2 production in RAW 264.7 cells induced by lipopolysaccharide (p < 0.05), which was accompanied by the inhibition of inducible nitric oxide synthase and cyclooxygenase-2 protein expression. Additionally, APT6 < 3 kDa downregulated the mRNA expression and production of TNF-α and IL-1β (p < 0.05). Mechanistically, these anti-inflammatory effects of APT6 < 3 kDa were shown by downregulating the MAPK and NF-κB pathways in a dose-dependent manner. Overall, 43 peptides were isolated from a certain fraction (F5) of APT6 < 3 kDa, demonstrating high antioxidative and anti-inflammatory activities. These results suggest that identified peptides from APT6 < 3 kDa possess natural antioxidants and hold potential as anti-inflammatory agents. [ABSTRACT FROM AUTHOR]

This study investigated the effects of Akebia quinata (AQ) leaf and fruit extract on acute alcohol-induced hepatotoxicity in AML12 cells. Different concentrations of AQ extracts (250 and 2500 μg/mL) were used to treat the AML12 cells with or without ethanol for 24 h for inducing acute alcohol cytotoxicity. AQ extract-treated AML12 cells showed enhanced expression of GSH-synthesizing enzymes and suppressed expression of oxidative stress makers such as NOX4, and decreased expression of tumor necrosis factor-α, inflammatory marker, in acute alcohol-induced hepatotoxicity. Furthermore, it was observed that 100 mM ethanol treatment of AML12 cells resulted in global change of mRNA expression in microarray, but AQ leaf extract treatment reversed the global change of mRNA expression pattern into normal condition. In conclusion, AQ extract or functional component from AQ can be useful therapeutic agent in acute alcohol-induced hepatotoxicity by reducing oxidative stress and inflammation responses. [ABSTRACT FROM AUTHOR]

This study investigated the effects of a silk peptide fraction obtained by incubating silk proteins with Protease N and Neutrase (SP-NN) on cognitive dysfunction of Alzheimer disease model rats. In order to elucidate underlying mechanisms, the effect of SP-NN on the expression of choline acetyltransferase (ChAT) mRNA was assessed in F3.ChAT neural stem cells and Neuro2a neuroblastoma cells; active amino acid sequence was identified using HPLC-MS. The expression of ChAT mRNA in F3.ChAT cells increased by 3.79-fold of the control level by treatment with SP-NN fraction. The active peptide in SP-NN was identified as tyrosine-glycine with 238.1 of molecular weight. Male rats were orally administered with SP-NN (50 or 300 mg/kg) and challenged with a cholinotoxin AF64A. As a result of brain injury and decreased brain acetylcholine level, AF64A induced astrocytic activation, resulting in impairment of learning and memory function. Treatment with SP-NN exerted recovering activities on acetylcholine depletion and brain injury, as well as cognitive deficit induced by AF64A. The results indicate that, in addition to a neuroprotective activity, the SP-NN preparation restores cognitive function of Alzheimer disease model rats by increasing the release of acetylcholine. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Vascular endothelial growth factor (VEGF) seems to be involved in the pathogenesis of chronic obstructive pulmonary disease (COPD), but its site-specific expression in lung tissue and the relationship with hypoxia inducible factor-1 alpha (HIF-1α) expression in chronic bronchitis (CB) type COPD have not been studied. Design and methods: We evaluated the expression of VEGF and its receptors in various compartments of lung tissue in three groups: non-smokers with normal lung function (non-smokers, n =10), smokers without COPD (healthy smokers, n =10) and smokers with CB (CB, n =10), using immunohistochemical staining and Western blotting. The expression of HIF-1α was assessed by enzyme-linked immunosorbent assay. Results: Compared with healthy smokers, VEGF expression in CB was significantly increased in bronchiolar epithelium, vascular endothelium and vascular smooth muscle (p <0.05). VEGF receptor (VEGFR)-2 expression in CB was also increased in bronchiolar smooth muscle, vascular endothelium and vascular smooth muscle compared with healthy smokers (p <0.05). The level of HIF-1α was increased in CB compared with healthy smokers and positively correlated with those of VEGF (r =0.64, p <0.05). Conclusion: VEGF and VEGFR-2 expressions were up-regulated in CB and increased expression of VEGF was related with HIF-1α. HIF-1α-regulated VEGF overexpression may be a characteristic of chronic bronchitis. [Copyright &y& Elsevier]

To examine the possible role of taurine chloramine (TauCl) in modulating the expression of adipokines in adipose tissue associated with obesity, we evaluated the effect of TauCl in human differentiated adipocytes in response to IL-1β. To study the physiological effects of TauCl on adipokine expression, differentiated adipocytes were treated with IL-1β in the presence or absence of TauCl at concentrations ranging from 200 to 600 μM for 7 days. Cell culture supernatants and total RNA were analyzed by ELISA and real-time PCR, respectively, to determine protein and mRNA levels of adipokines, including adiponectin, leptin, IL-6, and IL-8. Levels of proteins involved in relevant signaling pathways were investigated by western blotting. Stimulation with IL-1β significantly decreased levels of adiponectin and leptin in adipocytes, but increased levels of IL-6 and IL-8 in a dose-dependent manner. Treatment with TauCl significantly reversed the modulation of adipokine expression by inhibiting STAT-3 signaling in IL-1β-stimulated adipocytes, independent of MAPK signaling. TauCl treatment more significantly modulated the expression of adipokines in adipocytes stimulated with IL-1β than that of non-stimulated adipocytes, suggesting that TauCl plays a significant role in modulating the expression of adipokines under inflammatory conditions. In conclusion, TauCl and other taurine derivatives that inhibit the STAT-3 signaling pathway can modulate expression of adipokines and thus may be useful as therapeutic agents for obesity-related diseases. [ABSTRACT FROM AUTHOR]

Objectives. To further understand the expression regulation of MMP-1 and MMP-13 under physiological and pathological conditions, we investigated the combined effects of hypoxia and pro-inflammatory stimuli on the expression of MMP-1 and MMP-13 in rheumatoid synovial fibroblasts.Methods. Synovial fibroblasts were cultured under either hypoxic or normoxic conditions in the presence of IL-1β stimulation. The culture supernatant was analysed for secreted levels of VEGF, MMP-1 and MMP-13. Their gene expression was quantified with real-time and semi-quantitative PCR. Another group of cells was transfected with small-interfering RNA (siRNA) specific for hypoxia-inducible factor-1 α (HIF-1α). The protein levels of HIF-1α were detected by western blot analysis.Results. In response to 10 ng/ml of IL-1β under normoxia, the levels of MMP-1 and MMP-13 increased compared with the levels observed under hypoxia. IL-1β stimulation under hypoxia induced a 2-fold increase in the level of MMP-1 and a 2-fold decrease in the level of MMP-13 compared with cells cultured under normoxia. A similar pattern of differential expression for MMP-1 and MMP-13 was observed with 1 and 5 ng/ml IL-1β, but not at 0.1 ng/ml. The differential expression of MMPs under the combined effect of IL-1β and hypoxia was significantly attenuated by silencing HIF-1α with siRNA.Conclusions. Hypoxia in arthritic joints may differentially affect the IL-1β-stimulated expression of MMP-1 and MMP-13 in rheumatoid synovial fibroblasts. This effect is dependent on HIF-1α expression. This hypoxia-mediated differential effect should be taken into consideration when testing the efficiency of therapies that target HIF-1α. [ABSTRACT FROM PUBLISHER]

Abstract: In our previous study, diethylaminoethyl chitosan (DEAEC) was found to inhibit the viability of HeLa cells, a human uterine cervix cancer cell line. To identify the anti-proliferation activity of DEAEC, its mode of action was studied in further detail in HeLa cells. After incubation for 24h, DEAEC had significantly inhibited HeLa cell growth with an IC50 of 23.2μg/mL and showed strong apoptotic activity. After Hoechst 33258 staining, morphological changes and DNA degradation were observed. Cell cycle analysis and an Annexin V assay by flow cytometry revealed that DEAEC induced apoptosis in the HeLa cells by sub-G1 involving early stage apoptosis. RT-PCR and Western blotting analysis results showed that DEAEC induced apoptosis in the HeLa cells via up-regulation of caspase family enzyme (caspase-3, -8 and -9), p53, and Bax protein expressions, and down-regulation of Bcl-2 protein expression. [ABSTRACT FROM AUTHOR]

Abstract: Chitosan, naturally occuring biopolymer, has received considerable attention as a phamaceutical applications because of biocompatible, biodegradable and less toxic nature. In this study, chemically modified chitosans, aminoethyl-chitosans (AECs), were prepared in order to improve both water-solubility and bioactivity, and the effects of AECs on lipopolysaccharides (LPS)-induced inflammation in RAW264.7 mouse macrophages were investigated. AEC90 derived from 90% deacetylated chitosan showed strong inhibition capacity with regard to nitric oxide (NO) production than that of AEC50 derived from 50% deacetylated chitosan. Therefore further studies were coducted using AEC90. The production of prostaglandin E2 (PGE2) also inhibited by pretreatment of AEC90 in a dose-dependent manner which suggest the possibility of down-regulating their respective genes, inducible nitric oxide synthases (iNOS) and cyclooxygenase-2 (COX-2). Reverse transcrition-polymerase chain reaction (RT-PCR) and Western blot analysis revealed that AEC90 can affect both transcriptional and translational levels of iNOS and COX-2 expression via NF-κB pathway. Furthermore, AEC90 also suppressed the production of proinflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6), and the transcriptional and translational levels of such cytokines were also inhibited by AEC90 treatment. [Copyright &y& Elsevier]

Abstract: Clinical applications of acetylcholinesterase (AChE) inhibitors are widespread in Alzheimer’s sufferers in order to activate central cholinergic system and alleviate cognitive deficits by inhibiting the hydrolysis of acetylcholine. In this study, six kinds of chitooligosaccharides (COSs) with different molecular weight and degree of deacetylation were examined for their inhibitory effects against AChE. The 90-COSs exhibited potent AChE inhibitory activities compared to 50-COSs, while 90-MMWCOS (1000–5000Da) in the 90-COSs showed the highest activity. Cell culture experiment revealed that 90-MMWCOS suppressed the level of AChE protein expression and AChE activity induced by Aβ25–35 in PC12 cell lines. [Copyright &y& Elsevier]

Osteoporosis is characterized by low bone mass and elevated structural deterioration of the bone tissue, resulting in bone weakness with an increased risk of fracture. Considering biological activities of various phytochemicals extracted from apples, we herein demonstrated the potential antiosteoporotic effects of apple-derived nanovesicles (apple NVs) using osteoblastic MC3T3-E1 cells. Apple NVs significantly stimulated the growth of MC3T3-E1 cells. The cellular alkaline phosphatase (ALP) activity was significantly upregulated in the 5 μg/mL apple NVs-treated group. In addition, the concentrarion of mineralized nodules was significantly increased in the apple NVs-treated groups. Furthermore, apple NVs increased the expression of the genes and proteins associated with osteoblast growth and differentiation, such as Runx2, ALP, OPN, and BMP2/4, which further activated ERK- and JNK-related mitogen-activated protein kinase signaling. These results demonstrate that apple NVs have a potential to prevent osteoporosis by promoting osteoblastogenesis in osteoblastic MC3T3-E1 cells through regulating the BMP2/Smad1 pathways. [ABSTRACT FROM AUTHOR]

Abstract: Embryonic stem (ES) cells hold great potential as a renewable cell source for regenerative medicine and cell-based therapy. Despite the potential of ES cells, conventional stem cell culture methods do not enable the control of the microenvironment. A number of microscale engineering approaches have been recently developed to control the extracellular microenvironment and to direct embryonic stem cell fate. Here, we used engineered concave microwell arrays to regulate the size and shape of embryoid bodies (EBs)—cell aggregate intermediates derived from ES cells. Murine ES cells were aggregated within concave microwells, and their aggregate sizes were controlled by varying the microwell widths (200, 500, and 1000 μm). Differentiation of murine ES cells into three germ layers was assessed by analyzing gene expression. We found that ES cell-derived cardiogenesis and neurogenesis were strongly regulated by the EB size, showing that larger concave microwell arrays induced more neuronal and cardiomyocyte differentiation than did smaller microwell arrays. Therefore, this engineered concave microwell array could be a potentially useful tool for controlling ES cell behavior. [Copyright &y& Elsevier]

Abstract: Although the role of autophagy in tumorigenesis remains controversial, recent reports support the notion that inhibition of autophagy promotes tumor formation. Damage-regulated autophagy regulator (DRAM) has been identified as an effector molecule that is critical for p53-mediated apoptosis, and we investigated whether there might be other DRAM-like molecules linking autophagy and apoptosis. In this study, we cloned a novel DRAM-homologous protein, DRAM2, and showed that the expression of DRAM2 is down-regulated in ovarian tumors. DRAM2 is mainly localized in the lysosome, and co-localizes with DRAM. While expression of DRAM or DRAM2 individually did not induce cell death, co-expression of DRAM2 with DRAM significantly induced cell death, while the silencing of endogenous DRAM2 attenuated cell death, suggesting that DRAM2 is involved in cell death. Thus, we propose that reduced expression of DRAM2 may contribute to enhanced cell survival in tumor cells. [Copyright &y& Elsevier]