Identification of a TLR2-regulated gene signature associated with tumor cell growth in gastric cancer

Toll-like receptors (TLRs) are key regulators of innate immune responses, and their dysregulation is observed in numerous inflammation-associated malignancies, including gastric cancer (GC). However, the identity of specific TLRs and their molecular targets which promote the pathogenesis of human GC is ill-defined. Here, we sought to determine the clinical utility of TLR2 in human GC. TLR2 mRNA and protein expression levels were elevated in >50% of GC patient tumors across multiple ethnicities. TLR2 was also widely expressed among human GC cell lines, and DNA microarray-based expression profiling demonstrated that the TLR2-induced growth responsiveness of human GC cells corresponded with the up-regulation of six anti-apoptotic (BCL2A1, BCL2, BIRC3, CFLAR, IER3, TNFAIP3) and down-regulation of two tumor suppressor (PDCD4, TP53INP1) genes. The TLR2-mediated regulation of these anti-apoptotic and tumor suppressor genes was also supported by their increased and reduced expression, respectively, in two independent genetic GC mouse models (gp130^F/F and Gan) characterized by high tumor TLR2 expression. Notably, enrichment of this TLR2-regulated gene signature also positively correlated with augmented TLR2 expression in human GC tumors, and served as an indicator of poor patient survival. Furthermore, treatment of gp130^F/F and cell line-derived xenograft (MKN1) GC mouse models with a humanized anti-TLR2 antibody suppressed gastric tumor growth, which was coincident with alterations to the TLR2-driven gene signature. Collectively, our study demonstrates that in the majority of GC patients, elevated TLR2 expression is associated with a growth-potentiating gene signature which predicts poor patient outcomes, thus supporting TLR2 as a promising therapeutic target in GC.

Regulator of G protein signaling 2 (Rgs2) regulates neural crest development through Pparδ-Sox10 cascade

Neural crest cells are multipotent progenitors that migrate extensively and differentiate into numerous derivatives. The developmental plasticity and migratory ability of neural crest cells render them an attractive model for studying numerous aspects of cell progression. We observed that zebrafish rgs2 was expressed in neural crest cells. Disrupting Rgs2 expression by using a dominant negative rgs2 construct or rgs2 morpholinos reduced GTPase-activating protein activity, induced the formation of neural crest progenitors, increased the proliferation of nonectomesenchymal neural crest cells, and inhibited the formation of ectomesenchymal neural crest derivatives. The transcription of pparda (which encodes Pparδ, a Wnt-activated transcription factor) was upregulated in Rgs2-deficient embryos, and Pparδ inhibition using a selective antagonist in the Rgs2-deficient embryos repaired neural crest defects. Our results clarify the mechanism through which the Rgs2-Pparδ cascade regulates neural crest development; specifically, Pparδ directly binds to the promoter and upregulates the transcription of the neural crest specifier sox10. This study reveals a unique regulatory mechanism, the Rgs2-Pparδ-Sox10 signaling cascade, and defines a key molecular regulator, Rgs2, in neural crest development.

Bmp5 Regulates Neural Crest Cell Survival and Proliferation via Two Different Signaling Pathways

Neural crest progenitor cells, which give rise to many ectodermal and mesodermal derivatives, must maintain a delicate balance of apoptosis and proliferation for their final tissue contributions. Here we show that zebrafish bmp5 is expressed in neural crest progenitor cells and that it activates the Smad and Erk signaling pathways to regulate cell survival and proliferation, respectively. Loss-of-function analysis showed that Bmp5 was required for cell survival and this response is mediated by the Smad-Msxb signaling cascade. However, the Bmp5-Smad-Msxb signaling pathway had no effect on cell proliferation. In contrast, Bmp5 was sufficient to induce cell proliferation through the Mek-Erk-Id3 signaling cascade, whereas disruption of this signaling cascade had no effect on cell survival. Taken together, our results demonstrate an important regulatory mechanism for bone morphogenic protein-initiated signal transduction underlying the formation of neural crest progenitors. Stem Cells 2017;35:1003-1014.

PTEN Insufficiency Increases Breast Cancer Cell Metastasis In Vitro and In Vivo in a Xenograft Zebrafish Model

BACKGROUND/AIM

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) insufficiency is commonly found in breast cancer patients with metastasis. We investigated the mechanisms by which PTEN affects breast cancer metastatic behavior.

MATERIALS AND METHODS

Migration and invasion assay, western blot, immunofluorescent staining and zebrafish animal model were applied.

RESULTS

We showed that PTEN insufficiency induced an increase in MCF-7 cell migration and invasion through induction of epithelial-mesenchymal transition (EMT), which was triggered by up-regulation of the EMT-inducing transcriptional factors Zeb1, Zeb2, Snail, Slug and Twist. Simultaneously, E-cadherin expression was inhibited and P-cadherin was up-regulated. Further, WNT1 inducible signaling pathway protein 1 (WISP1) and lipocalin-2 (LCN2) expressions were increased after PTEN knockdown in MCF-7 cells, which also exhibited increased filamentous actin (F-actin) synthesis and extracellular matrix metalloproteinase-2 (MMP-2) and MMP-9 expression. We further showed that PTEN knockdown in MCF-7 cells could increase cell migration in the xenograft zebrafish model.

CONCLUSION

Our findings reveal new therapeutic targets for breast cancer patients with PTEN insufficiency.

Maternal psychologic problems increased the risk of childhood atopic dermatitis

BACKGROUND

Little is known about the effect of postnatal maternal psychologic problems on the development of childhood atopic disorders.

OBJECTIVES

To assess the association between early life maternal psychologic problems and atopic dermatitis (AD) in children in a national birth cohort.

METHODS

We used multistage, stratified systematic sampling to recruit 24,200 mother-newborn pairs from the Taiwan national birth registration. Maternal psychologic problems and potential confounders were gathered by the standard questionnaire at 6 months old. At 3 years of age, information about the development of AD was assessed by International Study of Asthma and Allergies in Childhood via home interviews. Multiple logistic regression analysis was performed to estimate the association of postnatal maternal psychologic problems (postpartum depression (PPD) and maternal mental health index) and AD.

RESULTS

The prevalence of physician-diagnosed AD was 10.5%. PPD increased the risk of subsequent physician-diagnosed AD in children after adjusting for potential confounders and other maternal mental health index (aOR = 1.42, 95% CI = 1.21-1.66). We observed that the risk of AD associated with PPD was not confounded by other social demographic factors such as maternal AD, maternal education, family income, breastfeeding, day care, and number of siblings.

CONCLUSIONS

Postpartum depression increased the risk of childhood AD even when other maternal mental health index and social demographic factors are considered. Early intervention of PPD might be helpful for AD prevention.

Deltex1 is inhibited by the Notch-Hairy/E(Spl) signaling pathway and induces neuronal and glial differentiation

Background

Notch signaling has been conserved throughout evolution and plays a fundamental role in various neural developmental processes and the pathogenesis of several human cancers and genetic disorders. However, how Notch signaling regulates various cellular processes remains unclear. Although Deltex proteins have been identified as cytoplasmic downstream elements of the Notch signaling pathway, few studies have been reported on their physiological role.

Results

We isolated zebrafish deltex1 (dtx1) and showed that this gene is primarily transcribed in the developing nervous system, and its spatiotemporal expression pattern suggests a role in neural differentiation. The transcription of dtx1 was suppressed by the direct binding of the Notch downstream transcription factors Her2 and Her8a. Overexpressing the complete coding sequence of Dtx1 was necessary for inducing neuronal and glial differentiation. By contrast, disrupting Dtx1 expression by using a Dtx1 construct without the RING finger domain reduced neuronal and glial differentiation. This effect was phenocopied by the knockdown of endogenous Dtx1 expression by using morpholinos, demonstrating the essential function of the RING finger domain and confirming the knockdown specificity. Cell proliferation and apoptosis were unaltered in Dtx1-overexpressed and -deficient zebrafish embryos. Examination of the expression of her2 and her8a in embryos with altered Dtx1 expression showed that Dxt1-induced neuronal differentiation did not require a regulatory effect on the Notch–Hairy/E(Spl) pathway. However, both Dtx1 and Notch activation induced glial differentiation, and Dtx1 and Notch activation negatively inhibited each other in a reciprocal manner, which achieves a proper balance for the expression of Dtx1 and Notch to facilitate glial differentiation. We further confirmed that the Dtx1–Notch–Hairy/E(Spl) cascade was sufficient to induce neuronal and glial differentiation by concomitant injection of an active form of Notch with dtx1, which rescued the neuronogenic and gliogenic defects caused by the activation of Notch signaling.

Conclusions

Our results demonstrated that Dtx1 is regulated by Notch–Hairy/E(Spl) signaling and is a major factor specifically regulating neural differentiation. Thus, our results provide new insights into the mediation of neural development by the Notch signaling pathway.

Electronic supplementary material

The online version of this article (doi:10.1186/s13064-015-0055-5) contains supplementary material, which is available to authorized users.

Prenatal air pollutant exposure and occurrence of atopic dermatitis

BACKGROUND

Hereditary and environmental factors have been related to the occurrence of atopic dermatitis (AD) in early childhood. However, the role of prenatal and early postnatal exposure to air pollutants has not been totally elucidated.

OBJECTIVES

To evaluate the association between prenatal air pollutant exposure and occurrence of AD.

METHODS

In total 24 200 infant-mother pairs were recruited to participate in the Taiwan Birth Cohort Study in 2005 using multistage stratified sampling. Medical history, including physician-diagnosed AD, was inquired by questionnaire at the infant's age of 6 months. Monthly averages of five criteria air pollutants - NO2 , CO, O3 , SO2 and PM10 - were retrieved from 66 air-quality-monitoring stations, and interpolated to all administrative districts using the kriging method. Exposure data during each of the three gestational trimesters and three months after birth were calculated for each study subject, and odds ratios (ORs) of AD occurrence were calculated by logistic regression.

RESULTS

Among the participants, 16 686 mother-infant pairs were qualified for and included in the analysis. Among them, 1206 infants (7·2%) had been diagnosed as having AD before the age of 6 months, and the prevalence was higher in boys (8·3%) than in girls (6·1%). The occurrence of AD was significantly associated with CO exposure during the whole gestational period [adjusted OR (aOR) 1·37, 95% confidence interval (CI) 1·06-1·78] and the first trimester (aOR 1·51, 95% CI 1·16-1·97). We did not observe any significant association among the other air pollutants during either the whole gestational period or any period of the three trimesters and 3 months after birth.

CONCLUSIONS

Our study found a relationship between AD occurrence and gestational exposure to CO, where exposure during the first trimester seemed to be the most important.

The epigenetic factor Kmt2a/Mll1 regulates neural progenitor proliferation and neuronal and glial differentiation

Multiple epigenetic factors play a critical role in cell proliferation and differentiation. However, their function in embryogenesis, especially in neural development, is currently unclear. The Trithorax group (TrxG) homolog KMT2A (MLL1) is an important epigenetic regulator during development and has an especially well-defined role in hematopoiesis. Translocation and aberrant expression of KMT2A is often observed in many tumors, indicating its proto-oncogenic character. Here, we show that Kmt2a was essential for neural development in zebrafish embryos. Disrupting the expression of Kmt2a using morpholino antisense oligonucleotides and a dominant-negative variant resulted in neurogenic phenotypes, including downregulated proliferation of neural progenitors, premature differentiation of neurons, and impaired gliogenesis. This study therefore revealed a novel function of Kmt2a in cell proliferation and differentiation, providing further insight into the function of TrxG proteins in neural development and brain tumors.

Analysis of sequence diversity through internal transcribed spacers and simple sequence repeats to identify Dendrobium species

The Orchidaceae is one of the largest and most diverse families of flowering plants. The Dendrobium genus has high economic potential as ornamental plants and for medicinal purposes. In addition, the species of this genus are able to produce large crops. However, many Dendrobium varieties are very similar in outward appearance, making it difficult to distinguish one species from another. This study demonstrated that the 12 Dendrobium species used in this study may be divided into 2 groups by internal transcribed spacer (ITS) sequence analysis. Red and yellow flowers may also be used to separate these species into 2 main groups. In particular, the deciduous characteristic is associated with the ITS genetic diversity of the A group. Of 53 designed simple sequence repeat (SSR) primer pairs, 7 pairs were polymorphic for polymerase chain reaction products that were amplified from a specific band. The results of this study demonstrate that these 7 SSR primer pairs may potentially be used to identify Dendrobium species and their progeny in future studies.

Serine protease inhibitor gabexate mesilate attenuates american cockroach-induced bronchial damage and inflammatory cytokine release

BACKGROUND AND OBJECTIVE

Allergic airway diseases are not only a T,2-mediated chronic airway inflammation, but also a condition of epithelial barrier defects and dysfunction. Allergens with protease activities are known factors that initiate respiratory epithelial damage. Cockroach allergy is the second leading cause of allergic respiratory airway diseases in Taiwan, and cockroach allergens have strong serine protease activity. This study aimed to determine the protective effect of the direct local administration of gabexate mesilate (GM) on American cockroach allergen (CraA)-induced human bronchial epithelial cell inflammation.

METHODS

BEAS-2B cells, from the human bronchial epithelial cell line, were stimulated with CraA or co-cultured with different doses of GM. Cellular morphologic changes were observed by microscopy and changes in chemokine mRNA expression and protein levels were determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and ELISA. Effects of specific inhibitors of ERK1/2 (U0126), INK (SP600125), and p38 MAPK (SB203580) on CraA-induced chemokine mRNA expression were also tested by RT-PCR.

RESULTS

GM prevented CraA-induced bronchial epithelial cell detachment and morphological changes. It had superior and more extensive suppression effects than specific target MAPK inhibitors in CraA-induced mRNA expression of IL-8, monocyte chemotactic protein (MCP) 1, chemokine (C-C motif) ligand 20, and granulocyte-macrophage colony-stimulating factor from the cells in a dose-dependent manner. CraA-induced IL-8 and MCP-1 protein production from BEAS-2B cells was also attenuated by GM.

CONCLUSIONS

The serine protease inhibitor GM has local protective effects against CraA-induced bronchial epithelial inflammation. The development of an inhaled or intranasal protease inhibitor may be a potential strategy for the treatment of allergic airway diseases induced by allergens with protease activities.

Etv5a regulates the proliferation of ventral mesoderm cells and the formation of hemato-vascular derivatives

Hematopoietic and vascular endothelial cells constitute the circulatory system and are both generated from the ventral mesoderm. However, the molecules and signaling pathways involved in ventral mesoderm formation and specification remain unclear. We found that zebrafish etv5a was expressed in the ventral mesoderm during gastrulation. Knockdown of Etv5a using morpholinos increased the proliferation of ventral mesoderm cells and caused defects in hematopoietic derivatives and in vascular formation. By contrast, the formation of other mesodermal derivatives, such as pronephros, somites and the gut wall, was not affected. Knockdown specificity was further confirmed by overexpression of an etv5a construct lacking its acidic domain. In conclusion, our data reveal that etv5a is essential for the inhibition of ventral mesoderm cell proliferation and for the formation of the hemato-vascular lineage.

Maternal employment and atopic dermatitis in children: a prospective cohort study

BACKGROUND

Considering the early onset of atopic dermatitis (AD), which most often arises in the first year of life, risk factors occurring very early in life must be considered. Little is known about the effects of maternal occupational exposure on the development of atopic disorders in children.

OBJECTIVES

The aim of this study was to evaluate associations between maternal employment and childhood AD.

METHODS

We used multistage stratified systematic sampling to recruit 24,200 mother-newborn pairs from the Taiwan national birth register. Information on maternal occupation categories, work stress, working time, shift work and potential confounders during pregnancy was gathered by questionnaires after birth. At 3 years of age, information on the development of AD was assessed by home interviews. Multiple logistic regression analysis was performed to estimate the association of maternal employment and AD.

RESULTS

Overall, 11,962 out of 19,381 mothers (61·7%) worked during pregnancy. The children of mothers who worked during pregnancy had an increased risk of AD compared with those whose mothers did not work [odds ratio (OR) 1·38, 95% confidence interval (CI) 1·25-1·53]. The children of mothers with a professional or technical occupation had a higher risk of AD (OR 1·64, 95% CI 1·44-1·87). The risk of AD was found to increase with maternal work stress during pregnancy in a dose-response manner (P(trend)<0·01). The mothers of children with AD had a longer working time than those without AD (P<0·0001). However, no significant association between AD and maternal shift work was found.

CONCLUSIONS

Working in professional or technical occupations increased the risk of childhood AD in addition to work stress during pregnancy.

Zebrafish rgs4 is essential for motility and axonogenesis mediated by Akt signaling

The schizophrenia susceptibility gene, Rgs4, is one of the most intensively studied regulators of G-protein signaling members, well known to be fundamental in regulating neurotransmission. However, little is known about its role in the developing nervous system. We have isolated zebrafish rgs4 and shown that it is transcribed in the developing nervous system. Rgs4 knockdown did not affect neuron number and patterning but resulted in locomotion defects and aberrant development of axons. This was confirmed using a selective Rgs4 inhibitor, CCG-4986. Rgs4 knockdown also attenuated the level of phosphorylated-Akt1, and injection of constitutively-activated AKT1 rescued the motility defects and axonal phenotypes in the spinal cord but not in the hindbrain and trigeminal neurons. Our in vivo analysis reveals a novel role for Rgs4 in regulating axonogenesis during embryogenesis, which is mediated by another schizophrenia-associated gene, Akt1, in a region-specific manner.

Dner inhibits neural progenitor proliferation and induces neuronal and glial differentiation in zebrafish

Delta/notch-like epidermal growth factor (EGF)-related receptor (DNER) is a single-pass transmembrane protein found to be a novel ligand in the Notch signaling pathway. Its function was previously characterized in the developing cerebellum and inner ear hair cells. In this study, we isolated a zebrafish homolog of DNER and showed that this gene is expressed in the developing nervous system. Overexpression of dner or the intracellular domain of dner was sufficient to inhibit the proliferation of neural progenitors and induce neuronal and glial differentiation. In contrast, the knockdown of endogenous Dner expression using antisense morpholino oligonucleotides increased the proliferation of neural progenitors and maintained neural cells in a progenitor status through inhibition of neuronal and glial differentiation. Through analysis of the antagonistic effect on the Delta ligand and the role of the potential downstream mediator Deltex1, we showed that Dner acts in Notch-dependent and Notch-independent manner. This is the first study to demonstrate a role for Dner in neural progenitors and neuronal differentiation and provides new insights into mediation of neuronal development and differentiation by the Notch signaling pathway.

Akt1 mediates neuronal differentiation in zebrafish via a reciprocal interaction with notch signaling

Akt1 is well known for its role in regulating cell proliferation, differentiation, and apoptosis and is implicated in tumors and several neurological disorders. However, the role of Akt1 in neural development has not been well defined. We have isolated zebrafish akt1 and shown that this gene is primarily transcribed in the developing nervous system, and its spatiotemporal expression pattern suggests a role in neural differentiation. Injection of akt1 morpholinos resulted in loss of neuronal precursors with a concomitant increase in post-mitotic neurons, indicating that knockdown of Akt1 is sufficient to cause premature differentiation of neurons. A similar phenotype was observed in embryos deficient for Notch signaling. Both the ligand (deltaA) and the downstream target of Notch (her8a) were downregulated in akt1 morphants, indicating that Akt1 is required for Delta-Notch signaling. Furthermore, akt1 expression was downregulated in Delta-Notch signaling-deficient embryos and could be induced by constitutive activation of Notch signaling. In addition, knockdown of Akt1 was able to nullify the inhibition of neuronal differentiation caused by constitutive activation of Notch signaling. Taken together, these results provide in vivo evidence that Akt1 interacts with Notch signaling reciprocally and provide an explanation of why Akt1 is essential for the inhibition of neuronal differentiation.

Phase II study of sorafenib in combination with cisplatin and 5-fluorouracil to treat recurrent or metastatic nasopharyngeal carcinoma

BACKGROUND

We aimed to investigate the efficacy and tolerability of sorafenib combined with cisplatin and 5-fluorouracil (5-FU) in patients with recurrent or metastatic nasopharyngeal carcinoma (NPC).

PATIENTS AND METHODS

It was a Simon two-stage designed trial. Chemotherapy-naive patients with recurrent or metastatic disease were enrolled. The regimen was sorafenib 400 mg orally b.i.d., cisplatin 80 mg/m(2) i.v. day 1, and 5-FU 1000 mg/m(2)/day CIV for 4 days, repeated every 21 days. After a maximum of six cycles of chemotherapy, patients received maintenance of sorafenib.

RESULTS

In total, 54 patients were enrolled. The objective response rate reached 77.8%, including 1 complete response and 41 partial responses. The median progression-free survival was 7.2 months (95% CI 6.8-8.4 months), and the median overall survival was 11.8 months (95% CI 10.6-18.7 months). Major toxic effects included hand-foot skin reaction, myelosuppression, and gastrointestinal (GI) reaction. The incidence of hemorrhage was 22.2%, and one patient with liver metastases died of GI bleeding. Contrast-enhanced ultrasonography was carried out in a subset of patients with liver metastases.

CONCLUSION

Combination of sorafenib, cisplatin (80 mg/m(2)) and 5-FU (3000 mg/m(2)) was tolerable and feasible in recurrent or metastatic NPC. Further randomized trials to compare sorafenib plus cisplatin and 5-FU with standard dose of cisplatin plus 5-FU in NPC are warranted.

CdO/ZnO core/shell nanostructures grown from single molecular precursors

Quadrilateral CdO nanoparticles were grown from cadmium cupferronate complex by injecting the precursor dissolved in octylamine into trioctylamine at 220 and 250 degrees C. CdO/ZnO core/shell structures were synthesized with a method similar to that of growing CdO cores by injecting the shell precursor following the growth of cores. The shell growth temperature was adjusted from 160 to 130 degrees C, and the shell precursor supply speed was adjusted from 4 to 8 ml/h. The obtained nanostructures were characterized by X-ray diffraction, high resolution transmission electron microscope, and ultraviolet-visible spectrophotometer. No core/shell structures formed if the shell precursor injection speed was as high as 8 ml/h. A very thin layer of ZnO shells would form on CdO cores if the shell precursor was injected at a speed of 4 ml/h at temperature of 160 degrees C, and the shells had good crystal quality. CdO/ZnO core/shell nanostructures were inclined to be spherical, and no homogeneous formation of ZnO nanoparticles was observed if the shell precursor injection temperature was lowered to 130 degrees C.

Estimating allergenicity of latex gloves using Hev b 1 and hevamine

BACKGROUND

Latex allergy continues to be an increasingly serious occupational health problem in Taiwan, where it affects approximately 6.8% to 12% of health care workers. Contrasting with reports from western countries, Hev b 1 and hevamine, and not Hev b 3, 5 or 6.02, are the major latex allergens among health care workers in Taiwan. This study aimed at evaluating the allergenicity of 30 brands of commercially available medical latex gloves in Taiwan in 2007.

METHODS

Residual Hev b 1 and hevamine from the gloves were measured by inhibition enzyme-linked immunosorbent assay using polyclonal antibodies against purified recombinant Hev b 1 and hevamine. The results were compared to those achieved with quantification of residual total extractable proteins and skin prick testing.

RESULTS

The residual extractable protein levels in 30 medical gloves all conformed to United States Food and Drug Administration regulations. All the gloves except one yielded strong skin prick reactions in latex-allergic individuals. The only brand of gloves that consistently produced no skin prick reactions in latex-allergic individuals contained the lowest residual levels of Hev b 1 (0.60 microg/g) and hevamine (0.07 microg/g).

CONCLUSIONS

Our results suggest that the measurement of residual extractable total proteins is not sufficient to assess the allergenicity of latex gloves and that Hev b 1 and hevamine may be used as indicator allergens in areas where they are major latex allergens, such as Taiwan.

A pilot study on low power pulse rate detection based on compressive sampling

Low power consumption is one of the key design challenges for various pervasive healthcare systems. Compressive Sampling (CS) is an emerging technique for reconstructing signals from data sampled under the Nyquist rate. CS has great potentials for low power pulse rate detection based on photoplethysmograph (PPG) signals, since by reducing the PPG data sampling rate the LEDs could be turned off for a prolonged period of time. Obviously the higher CS rate, the lower power consumption and lower pulse rate measurement accuracies. In this paper, a feasibility study of using CS for low power pulse rate detection was conducted. A miniature PPG measurement device based on our body sensor networks platform was employed for signal acquisition. Experiments for evaluation the pulse rate estimation and the power consumption were completed. Results suggested that the Gradient Projection for Sparse Reconstruction (GPSR) algorithm is a highly efficient for retrieving pulse rate from PPG signals. It was suggested that the CS rate should be approximate 3 for low power pulse rate detections with averaging estimation mean-square error being less than 5.

Fenofibrate attenuates endothelial monocyte adhesion in chronic heart failure: an in vitro study

BACKGROUND

Inflammation is implicated in chronic heart failure (CHF). In this study, the potential inhibitory effect of peroxisome proliferator-activated receptor-alpha (PPARalpha) activator fenofibrate on monocyte adhesion in CHF patients was investigated in vitro.

MATERIALS AND METHODS

Isolated peripheral blood mononuclear cells (PBMCs) were collected from 36 patients (aged 65 +/- 8 years) with symptomatic CHF and from 12 healthy control subjects. The cultured human aortic endothelial cells (HAECs) were stimulated with or without 2 ng mL(-1) tumour necrosis factor-alpha (TNF-alpha) and the inhibitory effects of fenofibrate at 25, 50, 100 and 200 microM on endothelial mononuclear cell adhesion were tested. Furthermore, the HAECs were stimulated with 70% sera obtained from CHF patients and control individuals, respectively, with or without pretreatments with fenofibrate. The endothelial expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) was then confirmed by mRNA expression and Western blot.

RESULTS

We found that the increased adhesion of PBMCs to TNF-alpha-stimulated HAECs in CHF patients was reduced when the HAECs were pretreated with fenofibrate (31% inhibition, P = 0.0121). However, pretreatment of the isolated PBMCs collected from CHF patients with fenofibrate failed to suppress their adherence to TNF-alpha-stimulated HAECs. Furthermore, stimulation of cultured HAECs with CHF patient sera significantly increased VCAM-1 and ICAM-1 expression, which could also be inhibited by fenofibrate.

CONCLUSIONS

The fenofibrate directly inhibits monocyte binding by TNF-alpha-activated HAECs, probably through preventing up-regulation of cell adhesion molecules by endothelial cells in response to inflammatory stimuli. This PPARalpha activator may have the potential to ameliorate vascular inflammation in patients with CHF.

A study of particulates and metallic element concentrations in temple

Concentrations of ambient suspended particulates were measured at Tzu Yun Yen temple in Taiwan (120 degrees , 34', 46.2''E, 24 degrees , 16', 17.1''N), where semi-open incense burning is characteristic. Many pilgrims from different areas with various beliefs visit the temple and burn incense. Samples were collected with a universal sampler used for measuring suspended particulate concentrations. Sampling period was from August 8, 2006, to October 6, 2006. The average PM(10) concentrations measured at the temple were 16% higher than 125 microg/m(3) (this value is the outdoor air quality standard according to Taiwan Environmental Protection Administration (EPA)). In coarse particulates (PM(2.5-10)), the mean metallic elements concentrations are in the order of Ca>Mg>Zn>Fe>Mn>Cr>Cu>Pb during weekend and weekday sampling. In addition, the fine particulates (PM(2.5)) mean metallic elements concentrations are in the order of Ca>Mg>Fe>Zn>Cr>Mn>Pb>Cu during weekend sampling and Ca>Fe>Mg>Zn>Cr>Mn>Pb>Cu during weekday sampling.

Identification of immunoglobulin E (IgE)-binding epitopes and recombinant IgE reactivities of a latex cross-reacting Indian jujube Ziz m 1 allergen

Ziz m 1 is a major Indian jujube (Zizyphus mauritiana) allergen involved in latex-fruit syndrome, and cDNA of the allergen has been cloned, sequenced and expressed in yeast by our laboratory previously. In this study, we performed an immunoglobulin E (IgE)-binding epitope analysis of Ziz m 1 using overlapping recombinant fragments. Eight overlapping recombinant fragments were generated from the recombinant Ziz m 1 allergen. The fragments were expressed in Escherichia coli and IgE-binding activities were evaluated by sera of latex-Indian jujube-allergic subjects and normal subjects using immunoblotting. Human allergic sera are not able to recognize fragments consisting of amino acid sequences 26-71, 119-280 and 119-291. However, residues at positions 26-199, 26-105, 26-86, 119-320 and 238-330 were found relevant in the IgE-binding. Our results indicate that (72)NISGHCSDCTFLGEE(86) and (292)VWNRYYDLKTNYSSSIILEYVNSGTKYLP(320) of Ziz m 1 are the sequences required for human IgE binding. Four corresponding peptides, (72)NISGHCSDCTE(86), (292)VWNRYYDLKT(301), (300)KTNYSSSIILEY(311) and (309)LEYVNSGTKYLP(320), were synthesized, and these peptides reacted with 70%, 100%, 70% and 70% of 10 allergic sera tested, as revealed by enzyme-linked immunosorbent assay. Sensitization to (292)VWNRYYDLKT(301) correlated significantly with the presence of allergic symptoms (P < 0.001). These findings will be useful in designing diagnostic and therapeutic approaches, thereby contributing to the development of specific immunotherapy for subjects with latex-fruit syndrome.