Publications by authors named "Shih-Chieh Chen"

25 Publications

  • Page 1 of 1

P-Cresylsulfate, the Protein-Bound Uremic Toxin, Increased Endothelial Permeability Partly Mediated by Src-Induced Phosphorylation of VE-Cadherin.

Toxins (Basel) 2020 01 21;12(2). Epub 2020 Jan 21.

Department of Anatomy, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.

The goal of our study was to investigate the impact of p-cresylsulfate (PCS) on the barrier integrity in human umbilical vein endothelial cell (HUVEC) monolayers and the renal artery of chronic kidney disease (CKD) patients. We measured changes in the transendothelial electrical resistance (TEER) of HUVEC monolayers treated with PCS (0.1-0.2 mM) similar to serum levels of CKD patients. A PCS dose (0.2 mM) significantly decreased TEER over a 48-h period. Both PCS doses (0.1 and 0.2 mM) significantly decreased TEER over a 72-h period. Inter-endothelial gaps were observed in HUVECs following 48 h of PCS treatment by immunofluorescence microscopy. We also determined whether PCS induced the phosphorylation of VE-cadherin at tyrosine 658 (Y658) mediated by the phosphorylation of Src. Phosphorylated VE-cadherin (Y658) and phosphorylated Src levels were significantly higher when the cells were treated with 0.1 and 0.2 mM PCS, respectively, compared to the controls. The endothelial barrier dysfunction in the arterial intima in CKD patients was evaluated by endothelial leakage of immunoglobulin G (IgG). Increased endothelial leakage of IgG was related to the declining kidney function in CKD patients. Increased endothelial permeability induced by uremic toxins, including PCS, suggests that uremic toxins induce endothelial barrier dysfunction in CKD patients and Src-mediated phosphorylation of VE-cadherin is involved in increased endothelial permeability induced by PCS exposure.
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http://dx.doi.org/10.3390/toxins12020062DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7076797PMC
January 2020

Integrate Weather Radar and Monitoring Devices for Urban Flooding Surveillance.

Sensors (Basel) 2019 Feb 17;19(4). Epub 2019 Feb 17.

Department of Civil and Ecological Engineering, I-Shou University, No.1, Sec. 1, Syuecheng Rd., Dashu District, Kaohsiung 84001, Taiwan.

With the increase of extreme weather events, the frequency and severity of urban flood events in the world are increasing drastically. Therefore, this study develops ARMT (automatic combined ground weather radar and CCTV (Closed Circuit Television System) images for real-time flood monitoring), which integrates real-time ground radar echo images and automatically estimates a rainfall hotspot according to the cloud intensity. Furthermore, ARMT combines CCTV image capturing, analysis, and Fourier processing, identification, water level estimation, and data transmission to provide real-time warning information. Furthermore, the hydrograph data can serve as references for relevant disaster prevention, and response personnel may take advantage of them and make judgements based on them. The ARMT was tested through historical data input, which showed its reliability to be between 83% to 92%. In addition, when applied to real-time monitoring and analysis (e.g., typhoon), it had a reliability of 79% to 93%. With the technology providing information about both images and quantified water levels in flood monitoring, decision makers can quickly better understand the on-site situation so as to make an evacuation decision before the flood disaster occurs as well as discuss appropriate mitigation measures after the disaster to reduce the adverse effects that flooding poses on urban areas.
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http://dx.doi.org/10.3390/s19040825DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6412549PMC
February 2019

Protein-bounded uremic toxin p-cresylsulfate induces vascular permeability alternations.

Histochem Cell Biol 2018 Jun 28;149(6):607-617. Epub 2018 Mar 28.

Department of Anatomy, Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung, 80708, Taiwan.

The goal of the present studies is to investigate that the impact of p-cresylsulfate (PCS) on the endothelial barrier integrity via in situ exposure and systemic exposure. Vascular permeability changes induced by local injection of PCS were evaluated by the techniques of both Evans blue (EB) and India ink tracer. Rats were intravenously injected with EB or India ink followed by intradermal injections of various doses of PCS (0, 0.4, 2, 10 and 50 µmol/site) on rat back skins. At different time points, skin EB was extracted and quantified. The administration of India ink was used to demonstrate leaky microvessels. Skin PCS levels were also determined by liquid chromatography-mass spectrometry. We also investigated whether the increased endothelial leakage occurred in the aortic endothelium in rats treated with 5/6 nephrectomy and intraperitoneal injection of PCS 50 mg/kg/day for 4 weeks. The aortic endothelial integrity was evaluated by increased immunoglobulin G (IgG) leakage. High doses of PCS, but not lower doses, significantly induced vascular leakage as compared to saline injection and EB leakage exhibited in time-dependent manner. A time-correlated increase in leaky microvessels was detected in the tissues examined. The injected PCS declined with time and displayed an inverse relationship with vascular leakage. Chronic kidney disease (CKD) rats administered with PCS, compared to control rats, had significantly higher serum levels of PCS and apparent IgG deposition in the aortic intima. Increased endothelial leakage induced by PCS in skin microvessels and the aorta of CKD rats suggests that the PCS-induced endothelial barrier dysfunction.
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http://dx.doi.org/10.1007/s00418-018-1662-0DOI Listing
June 2018

Vascular Hyperpermeability Response in Animals Systemically Exposed to Arsenic.

Int J Med Sci 2018 12;15(5):425-429. Epub 2018 Feb 12.

Department of Sports Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.

The mechanisms underlying cardiovascular diseases induced by chronic exposure to arsenic remain unclarified. The objectives of this study were to investigate whether increased vascular leakage is induced by inflammatory mustard oil in mice systemically exposed to various doses of arsenic and whether an increased vascular leakage response is still present in arsenic-fed mice after arsenic discontinuation for 2 or 6 months. ICR mice were fed water or various doses of sodium arsenite (10, 15, or 20 mg/kg/day; 5 days/week) for 8 weeks. In separate experiments, the mice were treated with sodium arsenite (20 mg/kg) for 2 or 8 weeks, followed by arsenic discontinuation for 2 or 6 months. Vascular permeability to inflammatory mustard oil was quantified using Evans blue (EB) techniques. Both arsenic-exposed and water-fed (control) mice displayed similar basal levels of EB leakage in the ears brushed with mineral oil, a vehicle of mustard oil. The levels of EB leakage induced by mustard oil in the arsenic groups fed with sodium arsenite (10 or 15 mg/kg) were similar to those of water-fed mice. However, increased levels of EB leakage in response to mustard oil stimulation were significantly higher in mice treated with sodium arsenite (20 mg/kg; high dose) than in arsenic-fed (10 or 15 mg/kg; low and middle doses) or control mice. After arsenic discontinuation for 2 or 6 months, mustard oil-induced vascular EB leakage in arsenic-fed (20 mg/kg) mice was similar to that in control mice. Dramatic increases in mustard oil-induced vascular leakage were only present in mice systemically exposed to the high arsenic dose, indicating the synergistic effects of the high arsenic dose and mustard oil.
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http://dx.doi.org/10.7150/ijms.23480DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5859764PMC
September 2018

Improving the properties of geopolymer containing oil-contaminated clay, metakaolin, and blast furnace slag by applying nano-SiO.

Environ Technol 2017 Jul 28;38(13-14):1619-1628. Epub 2017 Feb 28.

a Department of Civil and Ecological Engineering , I-Shou University , Kaohsiung City , Taiwan, ROC.

In this study, geopolymer specimens based on calcined oil-contaminated clays (OCCs), metakaolin replacements of OCCs, and blast furnace slag were manufactured by the addition of nano-SiO to improve their properties. The effects of adding 0, 1, 2, or 3% nano-SiO on the properties and microstructures of the geopolymer specimens were determined using compressive strength tests, flow tests, setting time tests, scanning electron microscopy (SEM), and silicon nuclear magnetic resonance spectroscopy (Si-NMR). The results showed that the setting time and flowability of the geopolymer specimens decreased and the compressive strength increased as the amount of nano-SiO increased. These results were supported by the SEM and Si-NMR assays. This study suggests that the addition of nano-SiO was beneficial and improved the properties of the geopolymer specimens containing calcined OCC.
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http://dx.doi.org/10.1080/09593330.2017.1293163DOI Listing
July 2017

A novel role for β2-microglobulin: a precursor of antibacterial chemokine in respiratory epithelial cells.

Sci Rep 2016 08 9;6:31035. Epub 2016 Aug 9.

Unité de Défense Innée et Inflammation, Inserm U874, Institut Pasteur, Paris, France.

We analyzed a panel of cationic molecules secreted in the culture medium of human respiratory epithelial cells (REC) upon activation by IL-1β and different pathogen-associated molecular patterns. A 9 kDa fragment derived from β2-microglobulin (B2M) was identified and named shed 9 kDa B2M (sB2M-9). The primary structure of sB2M-9 was revealed to increase its pI value that potentially could play an important role in innate defense. sB2M-9 exhibits antibacterial activity against Gram positive Staphylococcus aureus (SA) but not against Gram negative Klebsiella pneumonia (KP). Upon its binding to SA, sB2M-9 induces clumps, a phenomenon not observed with B2M. Migration of THP-1 monocytes exposed to SA clumps was significantly greater than that to SA without clumps. sB2M-9 binds to SA, more likely as a chemokine, to facilitate THP-1 migration. As a whole, we demonstrated that REC release a novel chemokine with antibacterial activity that is shed from B2M to facilitate THP-1 migration.
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http://dx.doi.org/10.1038/srep31035DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4977529PMC
August 2016

Increased Levels of Total p-Cresylsulfate Are Associated with Pruritus in Patients with Chronic Kidney Disease.

Dermatology 2016 4;232(3):363-70. Epub 2016 May 4.

Division of Cardiology, E-Da Hospital, Kaohsiung, Taiwan, ROC.

Background: Pruritus is a common and distressing symptom that affects patients with chronic kidney disease (CKD). Indoxyl sulfate (IS) and p-cresylsulfate (PCS) are uremic toxins with similar protein binding, dialytic clearance, and proinflammatory features. Pruritus in CKD may correlate better with uremic toxins than the glomerular filtration rate (GFR), suggesting that uremic toxins either in the central nervous system or peripherally may play an important role in the pathophysiology.

Objective: We sought to investigate the potential contribution of serum total IS and PCS to the pathogenesis of pruritus.

Methods: The serum levels of total IS and PCS concentrations were measured in all patients by using the Ultra Performance LC System. The characteristics of pruritus were assessed using a visual analog scale score and an interview questionnaire.

Results: Among the 320 CKD patients, 35% had pruritus. The patients with pruritus were older and had a higher frequency of diabetes mellitus, higher uric acid, calcium, phosphorus, creatinine, high-sensitivity C-reactive protein, and total IS and PCS levels, and lower albumin concentrations and estimated GFR (eGFR) than those without pruritus. Increasing concentrations of total PCS were independently and significantly associated with pruritus. Multiple logistic regression analysis revealed total PCS as an independent association factor for pruritus, even after full adjustment of known biomarkers. Furthermore, serum total PCS levels were positively associated with calcium, phosphorus, blood urea nitrogen, creatinine, and white blood cell count, and negatively associated with eGFR, hemoglobin, and hematocrit.

Conclusion: Our results indicate that total PCS may play a role in the pathogenesis of pruritus.
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http://dx.doi.org/10.1159/000445429DOI Listing
April 2017

Aortic smooth muscle cell alterations in mice systemically exposed to arsenic.

Heart Vessels 2016 May 2;31(5):807-15. Epub 2015 Jul 2.

Department of Dermatology, College of Medicine, Kaohsiung Medical University and Hospital, Tzu-you 1st Road, Kaohsiung, Taiwan.

Previous epidemiological studies showed that chronic arsenic exposure is related to increased cardiovascular disease incidence. The detailed biochemical mechanisms by which arsenic exerts its effects remain unknown. Vascular disease progression is characterized by smooth muscle cell (SMC) phenotypic switching, vessel wall reorganization, and platelet-derived growth factor (PDGF) production. The objective of this study was to examine early biochemical and structural changes in the aortas of ICR mice systemically exposed to arsenic. Animals were fed sodium arsenite (20 mg/kg) via gavage 5 days/week or Milli-Q water only (control) for 8 weeks. Aortic proteins were subjected to two-dimensional (2-D) differential gel electrophoresis and proteomic studies. Two 2-D gel protein spots were identified as the same protein, smooth muscle (SM)22α, using proteomics. SM22α and Rho kinase 2 gene and protein expression were significantly decreased in the aortic tissue of arsenic-exposed mice compared with that of control mice. No atherosclerotic lesion formation or tissue injury was detected in the aortic wall of either the arsenic-fed or the control group. However, the percent (%) SMC area of the aortic wall was significantly decreased in arsenic-fed mice compared with that in control mice. Additionally, the expression levels of PDGF-BB and early growth response-1 (Egr-1) were significantly higher in the arsenic group than that in the control group. These findings reveal biochemical alterations of SM22α, PDGF, and Egr-1 in conjunction with decreased SMC area in the aortic wall of arsenic-fed mice. Arsenic may initiate aortic SMC alterations that subsequently lead to vascular dysfunction.
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http://dx.doi.org/10.1007/s00380-015-0708-7DOI Listing
May 2016

Exercise prevents the increased anxiety-like behavior in lactational di-(2-ethylhexyl) phthalate-exposed female rats in late adolescence by improving the regulation of hypothalamus-pituitary-adrenal axis.

Horm Behav 2014 Sep 22;66(4):674-84. Epub 2014 Sep 22.

Department of Anatomy, Kaohsiung Medical University, Kaohsiung City, Taiwan.

Both the detrimental effects of early life adversity and the beneficial effects of exercise on the hypothalamic-pituitary-adrenal (HPA) axis have been reported. Early life exposure to di-(2-ethylhexyl)-phthalate (DEHP) may impair the development of endocrine system. In this study, we investigated the effects of lactational DEHP exposure on stress responses in late adolescent female rats and examined the protective role of treadmill running. Sprague-Dawley dams were fed with DEHP (10mg/kg per day) or vehicle during lactation. After weaning, the female offspring rats were trained to exercise on a treadmill for 5 weeks and then stressed by exploring on an elevated plus maze. The activities of HPA axis were evaluated by measuring the plasma levels of ACTH and corticosterone, the expressions of adrenal enzymes cholesterol side-chain cleavage enzyme (CYP11A1) and cytochrome P-450 11β-hydroxylase (CYP11B1), and the expression of hypothalamic glucocorticoid receptors (GR). The results demonstrate that DEHP-exposed rats exhibited enhanced anxiety-like behaviors. Increased hypothalamic GR and plasma ACTH levels, but decreased adrenal CYP11A1 and corticosterone levels, were observed in DEHP-exposed animals under stressed condition. Importantly, in DEHP-exposed animals, exercise during childhood-adolescence reduced anxiety-like behaviors by normalizing stress-induced alterations in ACTH level and adrenal CYP11A1 expression. The findings of this study suggest that treadmill running may provide beneficial effects on ameliorating the dysregulation of HPA axis in lactational DEHP-exposed adolescent female rats.
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http://dx.doi.org/10.1016/j.yhbeh.2014.09.010DOI Listing
September 2014

Microvascular dysfunction with increased vascular leakage response in mice systemically exposed to arsenic.

Cardiovasc Toxicol 2014 Sep;14(3):222-31

Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung, Taiwan,

The mechanisms underlying cardiovascular disease induced by arsenic exposure are not completely understood. The objectives of this study were to investigate whether arsenic-fed mice have an increased vascular leakage response to vasoactive agents and whether enhanced type-2 protein phosphatase (PP2A) activity is involved in mustard oil-induced leakage. ICR mice were fed water or sodium arsenite (20 mg/kg) for 4 or 8 weeks. The leakage response to vasoactive agents was quantified using the Evans blue (EB) technique or vascular labeling with carbon particles. Increased EB leakage and high density of carbon-labeled microvessels were detected in arsenic-fed mice treated with mustard oil. Histamine induced significantly higher vascular leakage in arsenic-fed mice than in water-fed mice. Pretreatment with the PP2A inhibitor okadaic acid or the neurokinin 1 receptor (NK1R) blocker RP67580 significantly reduced mustard oil-induced vascular leakage in arsenic-fed mice. The protein levels of PP2Ac and NK1R were similar in both groups. PP2A activity was significantly higher in the arsenic-fed mice compared with the control group. These findings indicate that microvessels generally respond to vasoactive agents, and that the increased PP2A activity is involved in mustard oil-induced vascular leakage in arsenic-fed mice. Arsenic may initiate endothelial dysfunction, resulting in vascular leakage in response to vasoactive agents.
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http://dx.doi.org/10.1007/s12012-014-9246-2DOI Listing
September 2014

Adaptive responses to glucose restriction enhance cell survival, antioxidant capability, and autophagy of the protozoan parasite Trichomonas vaginalis.

Biochim Biophys Acta 2014 Jan 17;1840(1):53-64. Epub 2013 Aug 17.

Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kwei-Shan, Taoyuan 333, Taiwan; Molecular Regulation and Bioinformatics Laboratory, Department of Parasitology, College of Medicine, Chang Gung University, Kwei-Shan, Taoyuan 333, Taiwan.

Background: To establish an infection in the vagina, Trichomonas vaginalis must adapt to various environmental cues for survival and further replication. Nutrient competition by lactobacilli, the major normal vaginal flora, is one of the mechanisms to limit the growth of other microorganisms. Additionally, lactobacilli produce H2O2 that can reduce the genital infections caused by other pathogens. Thus, the ability to overcome the metabolic stresses, such as glucose restriction (GR), as well as the oxidative stresses, is critical for T. vaginalis to establish an infection.

Methods: To gain insights into the molecular mechanisms of adaptation to GR, we utilized next-generation RNA sequencing (RNA-seq) to quantify the gene expression changes upon GR. Autophagy, a cytoprotective response to starvation, was monitored by using autophagy-specific staining, autophagy inhibition assay, and co-localization of autophagosomes with lysosomes.

Results: We demonstrated that GR promotes the survival of T. vaginalis. Besides, GR-cultivated cells exhibit higher H2O2 resistance. Our RNA-seq data revealed that genes involved in general energy metabolism were downregulated, whereas genes encoding glutamate metabolism-related aminotransferases were strikingly upregulated under GR. Furthermore, autophagy was first identified and characterized in T. vaginalis under GR.

Conclusions: These data suggest that GR induces a metabolic reprogramming, enhancing antioxidant ability and autophagy for cellular homeostasis to maintain survival.

General Significance: Our work not only led to significant advances in understanding the transcriptional changes in response to GR but also provided possible strategies elicited by GR for T. vaginalis to adapt to the vaginal microenvironment.
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http://dx.doi.org/10.1016/j.bbagen.2013.08.008DOI Listing
January 2014

Hyperglycemia: GDNF-EGR1 pathway target renal epithelial cell migration and apoptosis in diabetic renal embryopathy.

PLoS One 2013 28;8(2):e56731. Epub 2013 Feb 28.

Clinical Immunology Center, China Medical University Hospital, Taichung, Taiwan.

Maternal hyperglycemia can inhibit morphogenesis of ureteric bud branching, Glial cell line-derived neurotrophilic factor (GDNF) is a key regulator of the initiation of ureteric branching. Early growth response gene-1 (EGR-1) is an immediate early gene. Preliminary study found EGR-1 persistently expressed with GDNF in hyperglycemic environment. To evaluate the potential relationship of hyperglycemia-GDNF-EGR-1 pathway, in vitro human renal proximal tubular epithelial (HRPTE) cells as target and in vivo streptozotocin-induced mice model were used. Our in vivo microarray, real time-PCR and confocal morphological observation confirmed apoptosis in hyperglycemia-induced fetal nephropathy via activation of the GDNF/MAPK/EGR-1 pathway at E12-E15. Detachment between ureteric branch and metanephrons, coupled with decreasing number and collapse of nephrons on Day 1 newborn mice indicate hyperglycemic environment suppress ureteric bud to invade metanephric rudiment. In vitro evidence proved that high glucose suppressed HRPTE cell migration and enhanced GDNF-EGR-1 pathway, inducing HRPTE cell apoptosis. Knockdown of EGR-1 by siRNA negated hyperglycemic suppressed GDNF-induced HRPTE cells. EGR-1 siRNA also reduced GDNF/EGR-1-induced cRaf/MEK/ERK phosphorylation by 80%. Our findings reveal a novel mechanism of GDNF/MAPK/EGR-1 activation playing a critical role in HRPTE cell migration, apoptosis and fetal hyperglycemic nephropathy.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0056731PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3585314PMC
August 2013

Identification of putative miRNAs from the deep-branching unicellular flagellates.

Genomics 2012 Feb 18;99(2):101-7. Epub 2011 Nov 18.

Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan.

MicroRNAs (miRNAs) are a class of extensively studied RNAi-associated small RNAs that play a critical role in eukaryotic gene regulation. However, knowledge on the miRNA and its regulation in unicellular eukaryotes is very limited. In order to obtain a better understanding on the origin of miRNA regulation system, we used deep-sequencing technology to investigate the miRNA expression pattern in four deep-branching unicellular flagellates: Giardia lamblia, Trichomonas vaginalis, Tritrichomonas foetus, and Pentatrichomonas hominis. In addition to the known miRNAs that have been described in G. lamblia and T. vaginalis, we identified 14 ancient animal miRNA families and 13 plant-specific families. Bioinformatics analysis also identified four novel miRNA candidates with reliable precursor structures derived from mature tRNAs. Our results indicated that miRNAs are likely to be a general feature for gene regulation throughout unicellular and multicellular eukaryotes and some of them may derive from unconventional ncRNAs such as snoRNA and tRNA.
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http://dx.doi.org/10.1016/j.ygeno.2011.11.002DOI Listing
February 2012

Vascular hyperpermeability in response to inflammatory mustard oil is mediated by Rho kinase in mice systemically exposed to arsenic.

Microvasc Res 2011 Sep 16;82(2):182-9. Epub 2011 Jun 16.

Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.

The mechanisms underlying vascular dysfunction and cardiovascular disease induced by chronic arsenic exposure are not completely understood. We have previously shown that mice chronically fed sodium arsenite are hypersensitive to the permeability-increasing effects of inflammatory mustard oil. The aim of this study was to investigate whether RhoA/Rho kinase (ROCK)-mediated vascular leakage (hyperpermeability) is induced by mustard oil in mice systemically exposed to arsenic. Animals were orally fed water (control group) or sodium arsenite for 8weeks. We compared the blood pressure and microvessel density of the ears between these two groups. Both control and arsenic groups exhibited a similar mean arterial pressure and microvessel density. Microvessel permeability changes that occurred following mustard oil treatment in the presence of Y-27632, a ROCK inhibitor, were quantified using the Evans blue (EB) technique and vascular labeling with carbon particles. Both the excessive leakiness of EB and the high density of carbon-labeled microvessels upon stimulation with mustard oil in the arsenic-fed mice were reduced by Y-27632 treatment. However, RhoA and ROCK2 expression levels were similar between control and arsenic-fed mice. We further investigated ROCK2 levels and ROCK activity in the ears following mustard oil challenge. ROCK2 levels in mouse ears treated with mustard oil were higher in the arsenic group as compared with the control group. Following mustard oil application, ROCK activity was significantly higher in the arsenic-fed mice compared with the control mice. These findings indicate that increased ROCK2 levels and enhanced ROCK activity are responsible for mustard oil-induced vascular hyperpermeability in arsenic-fed mice.
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http://dx.doi.org/10.1016/j.mvr.2011.06.001DOI Listing
September 2011

Correlation of Tourette syndrome and allergic disease: nationwide population-based case-control study.

J Dev Behav Pediatr 2011 Feb-Mar;32(2):98-102

Children's Medical Center, China Medical University Hospital, No. 2 Yuh-Der Road, North District, Taichung, Taiwan.

Objective: Linkage between allergy and increased immune response activation in Tourette syndrome (TS) has been reported. We performed a matched case-control study to evaluate correlation between allergic diseases and TS.

Methods: Data in this case-control study were from the Taiwan National Health Insurance Research Database. The sample comprised 845 2- to 18-year-old patients with newly diagnosed TS in 2003–2007 and 3378 controls frequency matched with cases on age, sex, and urbanization level. Unconditional logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CIs) of the association between allergic disease (e.g., allergic rhinitis, atopic dermatitis, asthma, and allergic conjunctivitis), the number of allergic comorbidities, and TS.

Results: The majority (76.0%) of incident TS cases were boys; the 4 allergic diseases strongly correlated with higher risk of TS. In a model simultaneously considering all 4 allergic diseases, subjects with allergic rhinitis showed double the risk of TS (adjusted OR = 2.18, 95%CI 1.83–2.59; p < 0.0001); adjusted ORs were 1.82, 1.61, and 1.33, respectively, for asthma (95% CI 1.47–2.24; p < 0.0001), dermatitis (95%CI 1.32–1.95; p < 0.0001), and allergic conjunctivitis (95% CI 1.13–1.57; p < 0.001). Risk increased with number of comorbidities (p < 0.0001); this association was positively modified by age (p < 0.0001).

Conclusions: Our data showed significant correlation between allergic diseases and TS. Risk also increased with number of allergic comorbidities and with age. Further studies on the mechanism of neuroimmunology of TS are required.
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http://dx.doi.org/10.1097/DBP.0b013e318208f561DOI Listing
July 2011

Malate dehydrogenase is negatively regulated by miR-1 in Trichomonas vaginalis.

Parasitol Res 2009 Nov 24;105(6):1683-9. Epub 2009 Sep 24.

Molecular Regulation and Bioinformatics Laboratory, Chang Gung University, Taoyuan, Taiwan.

MicroRNAs are highly conserved small noncoding RNAs that can suppress protein translation through complementary binding to target mRNAs. We used a novel approach to identify miRNA targets in the protist Trichomonas vaginalis by comparing the levels of differentially expressed proteins and genes in the trophozoite and amoeboid stages. We observed that the T. vaginalis malate dehydrogenase (Tv_MDH) gene was upregulated 20-fold in the amoeboid stage, but the protein level was reduced by 4.5-fold. Bioinformatics analysis revealed that the Tv_MDH mRNA contains putative target sites of the miR-1 family. The expression level of endogenous tva-miR-1 in the amoeboid stage was 50-fold higher than in the trophozoite stage. Transfection of trophozoites with tva-miR-1 mimics reduced Tv_MDH protein expression by 60%. Based on these experimental data, we conclude that Tv_MDH is negatively regulated by tva-miR-1. The results of this study demonstrate that a combination of proteomic and transcriptomic approaches is a powerful tool for identifying miRNA targets.
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http://dx.doi.org/10.1007/s00436-009-1616-5DOI Listing
November 2009

Identification of microRNA in the protist Trichomonas vaginalis.

Genomics 2009 May 3;93(5):487-93. Epub 2009 Feb 3.

Molecular Regulation and Bioinformatics Laboratory, Chang Gung University, Taoyuan 333, Taiwan.

MicroRNAs (miRNAs) are a class of small noncoding RNAs that have important regulatory roles in multicellular organisms. However, miRNA has never been identified experimentally in protist. Direct cloning of 438 expressed miRNA tags by microRNA serial analysis of gene expression from the parasitic protist Trichomonas vaginalis identified nine candidate miRNAs. Bioinformatics analysis of the corresponding genomic region revealed that these miRNA candidates contain a classical stem-loop-stem structure of pre-microRNAs. Analysis of the 20 nt long mature tva-miR-001 showed that it is an intergenic miRNA located at the scaffold DS113596. Tva-miR-001 was differentially expressed in the trophozoite, pseudocyst and amoeboid stages. Based on the experimental results of the present study, we provided solid evidence that protist possesses a miRNA regulating network comparable with multicellular organisms for the first time.
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http://dx.doi.org/10.1016/j.ygeno.2009.01.004DOI Listing
May 2009

Vascular leakage induced by exposure to arsenic via increased production of NO, hydroxyl radical and peroxynitrite.

Microvasc Res 2008 Apr 5;75(3):373-80. Epub 2008 Jan 5.

Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung, Taiwan.

Previous studies have shown that in situ exposure to arsenic induced increased vascular leakage. However, the underlying mechanism remains unclear. Reactive nitrogen and oxygen species such as nitric oxide (NO) and hydroxyl radical (OH(-)) are known to affect vascular permeability. Therefore, the goal of our present studies is to investigate the functional impact of the generation of NO or OH(-) on arsenic-induced vascular leakage. Vascular permeability changes were evaluated by means of Evans blue (EB) assay. Rats were anesthetized and intravenously injected with EB. Permeability changes were induced in back skin by intradermal injections of sodium arsenite mixed with NOS inhibitor: N(omega)-Nitro-L-arginine methyl ester (L-NAME) or aminoguanidine (AG) and OH(-) scavenger: 1,3 Dimethyl-2 thiourea (DMTU). Experiments were also performed to determine whether DMTU mixed with L-NAME would further inhibit arsenic-induced vascular leakage as compared with attenuation effects by either DMTU or L-NAME. One hour after administration, EB accumulated in the skin was extracted and quantified. Both L-NAME (0.02, 0.1 and 0.5 micromol/site) and DMTU (0.05, 0.2 and 1.2 micromol/site) inhibited the increase in vascular leakage induced by arsenite. However, only high dose (1 micromol/site) of AG significantly attenuated arsenite-induced vascular leakage. In contrast, neither D-NAME (0.02, 0.1 and 0.5 micromol/site) nor AG (0.04 and 0.2 micromol/site) attenuated increased vascular leakage by arsenic. DMTU mixed with L-NAME caused no further inhibition of arsenic-induced vascular leakage by either DMTU or L-NAME. The techniques of India ink and immunostaining were used to demonstrate both vascular labeling and nitrotyrosine staining in tissue treated with arsenic. L-NAME apparently reduced the density of leaky vessels and the levels of peroxynitrite staining induced by arsenite. These results suggest that NO, OH(-) and peroxynitrite play a role in increased vascular permeability induced by arsenic exposure.
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http://dx.doi.org/10.1016/j.mvr.2007.12.004DOI Listing
April 2008

Functional neuroprotective effect of CGS 26303, a dual ECE inhibitor, on ischemic-reperfusion spinal cord injury in rats.

Exp Biol Med (Maywood) 2007 Feb;232(2):214-8

Department of Anesthesiology, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Taiwan.

Endothelin-1 (ET-1) has been implicated in many neurological diseases, including subarachnoid hemorrhage (SAH) and cerebral ischemia. ET-1 is also proved to deteriorate the ischemia-reperfusion injury in many organs. Our previous studies demonstrated that the endothelin-converting enzyme (ECE) inhibitor, CGS 26303, possessed beneficial effects for the treatment of SAH and transient middle cerebral artery occlusion. In this study, we investigated the neuroprotective effect of CGS 26303 on the locomotor function and mRNA expression of heme-oxygenase-1 (HO-1) in rats subjected to a 15-min spinal cord ischemia. The results showed that pretreatment with CGS 26303 significantly preserved the locomotor function and decreased the paraplegia rate at Days 1 and 3 as compared with a saline-treated group. Furthermore, rats pretreated with CGS 26303 had a significant increase in the levels of HO-1 mRNA expression at Day 3 when compared with animals pretreated with saline after spinal cord ischemia and the sham operation group. These results suggest that CGS 26303 may have a promising neuroprotective effect in the spinal cord after ischemia-reperfusion injury, and beneficial result may be due to an adaptive mechanism involved by HO-1 overexpression.
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February 2007

Involvement of substance P and neurogenic inflammation in arsenic-induced early vascular dysfunction.

Toxicol Sci 2007 Jan 20;95(1):82-8. Epub 2006 Oct 20.

Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University and Department of Clinical Research, Kaohsiung Medical University Hospital, Taiwan, ROC.

Vascular-related diseases, including Blackfoot Disease and atherosclerosis, are prominent clinical findings among populations residing in arseniasis areas. While oxidative stress provided a general but nonspecific mechanistic base for arsenic-induced endothelial cell damage in vitro, more specific mechanism is needed to explain the highly targeted vascular lesions induced by arsenic in vivo. Based on our previous studies, we hypothesized that arsenic exerted its action on blood vessels via the neurogenic inflammation process involving release of a neuropeptide (substance P) and activation of endothelial Neurokinin 1 (NK-1) receptor in vivo. Indeed, our present study demonstrated a significantly higher substance P levels in arsenic-treated tissues when compared to saline-treated controls indicating a rapid release of substance P under the influence of arsenic. Furthermore, the arsenic-induced vascular leakage could be significantly reduced when the neurogenic inflammation process was interrupted (via either disruption on the release of substance P, interference on the action of substance P, or blockage of endothelial NK-1 receptor) showing that the neurogenic inflammation process was indeed involved. Histamine release was not found to play a significant role in arsenic-induced vascular permeability change. Our present study affirmed a de novo concept that a pathophysiological mechanism involving the neurogenic release of substance P and activation of endothelial NK-1 receptor underlies the arsenic-induced vascular injury and dysfunction in vivo. This pathophysiological process constituted a two-tiered biological interaction between the nervous system and vascular system and therefore was not readily unveiled by traditional in vitro studies in the past. Our present finding unveiled an important de novo concept on arsenic vascular toxicity in vivo.
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http://dx.doi.org/10.1093/toxsci/kfl136DOI Listing
January 2007

Effects of hyperthermia pretreatment on expression of heme oxygenase-1 and nitric oxide synthase in rats subjected to experimental anaphylactic shock.

Chin J Physiol 2005 Dec;48(4):193-9

Department of Anatomy and Physiology, Kaohsiung Medical University, Taiwan.

Previous studies have shown that hyperthermia pretreatment results in an attenuation of increased vascular leakage in rats subjected to experimental anaphylactic shock. It is known that both nitric oxide synthase (NOS) and heme oxygenase-1 (HO-1) play a role in the maintenance of microvascular integrity. In the study, we investigated the effect of hyperthermia pretreatment on mRNA expression of endothelial NOS (eNOS), inducible NOS (iNOS), and HO-1 in heated or nonheated rats subjected to anaphylactic shock using a semi-quantitative RT-PCR. Protein contents of eNOS and HO-1 in tissue were also assayed. Plasma nitrite and nitrate before and after induction of anaphylactic shock were quantified using a NO analyzer. The heated, anaphylactic rats showed a significant increase of HO-1 mRNA expression in heart as compared to both non-heated, anaphylactic and control rats. HO-1 protein contents in both heart and lung tissues in the heated, anaphylactic rats were significantly higher than both non-heated, anaphylactic and control rats. Protein contents of eNOS in various tissues appeared to be the same among groups. No significant change of iNOS mRNA expression was detected among groups. Plasma nitrite and nitrate before and after anaphylactic treatment appeared to be the same among groups. These data suggest that reduction of anaphylactic hypotension by hyperthermia pretreatment in rats subjected to anaphylactic shock may be resulted from over-expression of HO-1 rather than NOS in various tissues.
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December 2005

CGS 26303 upregulates mRNA expression of heme oxygenase-1 in brain tissue of rats subjected to experimental subarachnoid hemorrhage.

J Cardiovasc Pharmacol 2004 Nov;44 Suppl 1:S474-8

Department of Neurosurgery, Kaohsiung Medical University, Kaohsiung, Taiwan.

Previous studies indicate that intravenous infusion of CGS 26303, an endothelin-converting enzyme inhibitor, prevents and reverses cerebral vasospasm after experimental subarachnoid hemorrhage. Attenuation of the vasospastic response could result from enhanced production of nitric oxide via activation of endothelial nitric oxide synthase, neuronal nitric oxide synthase, or inducible nitric oxide synthase in brain tissue. Carbon monoxide has the same attenuation effect and is synthesized by inducible heme-oxygenase- 1 or constitutive heme-oxygenase-2. In this study, we investigated the effect of endothelin-converting enzyme inhibitor on mRNA expression of endothelial nitric oxide synthase, neuronal nitric oxide synthase, inducible nitric oxide synthase, heme-oxygenase- 1 and heme-oxygenase-2 in brain tissue of rats subjected to subarachnoid hemorrhage using semi-quantitative reverse transcription-polymerase chain reaction. The results showed that gene expression of inducible nitric oxide synthase or HSP70 was not detected in all groups of rats (n = 5/group). Expression of endothelial nitric oxide synthase, neuronal nitric oxide synthase or heme-oxygenase-2 mRNA in brain tissue in the groups of subarachnoid hemorrhage or subarachnoid hemorrhage treated with endothelin-converting enzyme inhibitor appeared to be the same as compared with control rats. The subarachnoid hemorrhage rats treated with endothelin-converting enzyme inhibitor showed a significant increase in the levels of heme-oxygenase-1 mRNA expression as compared with both subarachnoid hemorrhage and control rats. These data suggest that the reduction of cerebral vasospasm by CGS 26303 in rats subjected to experimental subarachnoid hemorrhage may result from both over-expression of heme-oxygenase-1 in brain tissue and suppression of endothelin biosynthesis in basilar arteries.
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http://dx.doi.org/10.1097/01.fjc.0000166310.71431.52DOI Listing
November 2004

A mouse model for the study of vascular permeability changes induced by arsenic.

Toxicol Mech Methods 2005 ;15(6):433-7

Division of Environmental Health and Occupational Medicine, National Health Research Institutes, Taiwan, R.O.C.

The primary objective of our present research was to develop an animal model for the investigation of arsenic-induced vasculopathy. Epidemiological evidence indicated that, aside from cancer, cardiovascular-related diseases were probably the most prominent health concerns in arseniasis areas. Although there were many investigations on the effect of arsenic on endothelial cells, most of these studies were conducted under in vitro conditions. A good animal model for studying the effects of arsenic on vascular integrity in vivo is very much needed. We have previously developed a rat model that could be used to demonstrate vascular changes induced by arsenic in vivo. In the present report, we are introducing a new model that is even more sensitive, economical, and effective than our original rat model. Taking advantage of the characteristics of mouse ears (thin, delicate, and with easily visible blood vessels), we demonstrated the pattern and extent of vascular leakage induced by arsenic clearly, quantitatively and convincingly. With this model, we demonstrated a time-dependent increase in vascular permeability induced by arsenic (a fourfold increase in vascular leakage was observed between 10-60 minutes). With this model, we were also able to demonstrate that small caliber vessels were more vulnerable than vessels of larger caliber. Thus, this animal model can provide dynamic information (from toxic effects, pathology, and functional alterations to cellular/molecular mechanisms) that cell culture techniques are unable to provide. The introduction of this model hopefully will stimulate and inspire many other new in vivo investigations on vasculopathy induced by arsenic or other chemicals in the future.
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http://dx.doi.org/10.1080/15376520500195640DOI Listing
October 2012

Vascular permeability alterations induced by arsenic.

Hum Exp Toxicol 2004 Jan;23(1):1-7

Department of Anatomy, Kaohsiung Medical University, Taiwan, ROC.

The impact of arsenic on the integrity of blood vessels in vivo via in situ exposure (local injection) of arsenic was investigated. Vascular permeability changes were evaluated by means of the Evans blue assay and the India ink tracer techniques. Rats were intravenously injected with Evans blue followed by intradermal injections of various doses of sodium arsenite on the back skins of the animals. Evans blue at different time points was extracted and assayed as indices of vascular leakage. Skin at various time point injection sites was sampled for arsenic measurement via graphite furnace atomic absorption spectroscopy. Our time course study with Evans blue technique demonstrated a biphasic pattern of vascular permeability change: an early phase of permeability reduction and a later phase of permeability promotion at all dose levels tested. The India ink tracer technique also demonstrated a time-correlated increase in vascular labelling in the tissues examined, signifying an increase in vascular leakage with time. Moreover, we found that despite an early increase in tissue arsenic content at time of injection, tissue arsenic declined rapidly and returned to near control levels after 30-60 min. Thus, an inverse correlation between tissue arsenic content and the extent of vascular permeability was apparent. This study provides the first demonstration that in situ exposure to arsenic will produce vascular dysfunction (vascular leakage) in vivo.
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http://dx.doi.org/10.1191/0960327104ht407oaDOI Listing
January 2004

In vitro efficiency of intra- and extracellular immunization with mouse anti-YGNNV antibody against yellow grouper nervous necrosis virus.

Vaccine 2002 Aug;20(25-26):3221-9

Molecular Genetics Laboratory, Institute of Zoology, Academia Sinica, 128 Academia Road, Section 2, NanKang, Taipei 11529, Taiwan.

Mouse monoclonal antibody (MAb-18) against yellow grouper nervous necrosis virus (YGNNV) coat protein was developed and assayed for its neutralization ability. In the present study, we cloned and sequenced the cDNAs encoding heavy (gamma) and light (kappa) chains by constructing a cDNA library of the MAb-18 hybridoma. Three expression vectors, pCMV-NNV-18H (gamma), pCMV-NNV-18L (kappa), and pCMV-NNV-18HL (both gamma and kappa chains) were constructed and successfully expressed in grouper brain (GB) cells. Western blotting results indicated the secretion of antibody in to the medium with successful folding. Extracellular antibodies secreted by the pCMV-NNV-18HL transfected GB cells, neutralized well with YGNNV and showed the highest neutralization index (log(10) of NI) value 4. A significant reduction of titre (99.9%) was observed, when the intracellularly immunized GB cells were propagated with the YGNNV. These preliminary demonstrations suggest the immunoprophylactic use of plasmid constructs encoding the genes of mouse MAbs and the possibility of producing transgenic pathogen-free spawners and larvae, which contain freely available MAbs against pathogen in the circulation.
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http://dx.doi.org/10.1016/s0264-410x(02)00239-6DOI Listing
August 2002