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Croatian Medical Journal Aug 2001Sulfasalazine, a nonsteroidal anti-inflammatory drug, is effective in treating some autoimmune diseases, but its mechanism of action is unclear. To determine whether...
AIM
Sulfasalazine, a nonsteroidal anti-inflammatory drug, is effective in treating some autoimmune diseases, but its mechanism of action is unclear. To determine whether dendritic cells could be a possible target of the drug, we studied the effects of sulfasalazine and its metabolites, aminosalicylate and sulfapyridine, on in vitro maturation (terminal differentiation) of human myeloid dendritic cells.
METHODS
We prepared immature dendritic cells by incubating CD14-positive cells in the presence of granulocyte- macrophage colony-stimulating factor and interleukin (IL)-4. The cells were matured by addition of tumor necrosis factor (TNF)-a, IL-1 beta, and prostaglandin E2 in the presence of sulfasalazine or its metabolites -- aminosalicylate and sulfapyridine, or their combinations. We quantified the effect of drugs on the dendritic cell characteristics, such as stimulation of autologous and allogeneic pan-T cell proliferation, surface marker phenotype, IL-12 p40 subunit secretion, and activation of nuclear transcription factor (NF)-kappa B.
RESULTS
Dendritic cells treated with sulfasalazine (1.25 micromol/L or 2.5 micromol/L) could not stimulate T cells (p<0.028, two-sided paired t-test). In distinction to drug-free maturing dendritic cells, 2.5 micromol/L sulfasalazine upregulated the levels of CD14 and CD68 and downregulated the levels of CD40, CD80, and CD83 (for all CD markers, p<0.03 for difference between measurements in the absence and the presence of sulfasalazine). From concentration-dependent changes in CD83 expression, we found an apparent ID50 >>1.5 micromol/L sulfasalazine. The apparent ID50 value for aminosalicylate-inhibited maturation was 4 micromol/L. Sulfapyridine had no effect. At 1.25 micromol/L, sulfasalazine largely inhibited NF-kB activation in dendritic cells.
CONCLUSION
Maturing human dendritic cells are hundred-fold more sensitive to sulfasalazine than T cells and NK cells and the most sensitive human cells described so far. Thus, dendritic cell maturation is an important target of sulfasalazine. Because of the role of dendritic cells in (auto)immunity, inhibition of their maturation might provide a target for further optimization of sulfasalazine therapy.
Topics: Anti-Inflammatory Agents, Non-Steroidal; Antigens, CD; Cell Division; Dendritic Cells; Flow Cytometry; Humans; Killer Cells, Natural; NF-kappa B; Phenotype; Sulfasalazine; T-Lymphocytes
PubMed: 11471196
DOI: No ID Found -
Journal of the American College of... Jan 2007We investigated whether lipopolysaccharide (LPS), a proximate cause of inflammation, activates calcineurin in cardiac myocytes and if calcineurin regulates apoptosis in...
OBJECTIVES
We investigated whether lipopolysaccharide (LPS), a proximate cause of inflammation, activates calcineurin in cardiac myocytes and if calcineurin regulates apoptosis in this setting.
BACKGROUND
Calcineurin regulates myocardial growth and hypertrophy, but its role in inflammation is unknown. Calcineurin has proapoptotic or antiapoptotic effects depending on the stimuli.
METHODS
Calcineurin activity was measured in left ventricular myocytes from adult Sprague Dawley rats. Cardiac apoptosis was measured by terminal deoxy-nucleotidyl transferase-mediated dUTP nick end-labeling staining and caspase-3 activity after in vitro and in vivo exposure to LPS.
RESULTS
Lipopolysaccharide increased calcineurin activity in myocytes over 1 to 24 h (t 1/2 = 4.8 h) with an EC(50) of 0.80 ng/ml LPS (p < 0.05, n = 4). The LPS (10 ng/ml) effects were mimicked by angiotensin II (Ang II) (100 nmol/l); both increased calcineurin activity and induced apoptosis without additive effects (p < 0.05, n = 5 to 9). Lipopolysaccharide and/or Ang II effects were prevented by 1 h pre-treatment with an Ang II type 1 receptor blocker (losartan, 1 micromol/l), calcineurin inhibitor (cyclosporin A, 0.5 micromol/l), calcium chelator (1,2-Bis(2-amino-5-fluorophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis(acetoxymethyl) ester, 0.1 micromol/l), or by inhibiting sarcoplasmic reticulum (SR) calcium (Ca)-ATPase (thapsigargin, 1 micromol/l) or SR calcium release channel (ryanodine, 1 micromol/l). Left ventricular apoptosis increased from 4 to 24 h after LPS (1 mg/kg intravenously) in vivo, but not in rats pre-treated with cyclosporin A (20 mg/kg/day subcutaneously) for 3 days (p < 0.05, n = 5).
CONCLUSIONS
In cardiac myocytes, LPS activates calcineurin in association with apoptosis by Ang II and SR calcium-dependent mechanisms. This expands the paradigm for cardiac calcineurin to be activated by low levels of LPS in inflammation and chronic conditions (e.g., infections, smoking, and heart failure).
Topics: Analysis of Variance; Animals; Apoptosis; Calcineurin; Heart Ventricles; Lipopolysaccharides; Myocytes, Cardiac; Rats; Rats, Sprague-Dawley
PubMed: 17258096
DOI: 10.1016/j.jacc.2006.10.043 -
Journal of Vascular Surgery Jul 2004The cardioprotective effect of red wine has been attributed to resveratrol. The resveratrol-induced protection against ischemia-reperfusion (I/R) injury has been...
OBJECTIVE
The cardioprotective effect of red wine has been attributed to resveratrol. The resveratrol-induced protection against ischemia-reperfusion (I/R) injury has been documented in heart, kidney, and brain. Resveratrol scavenges free O(2) radicals and upregulates nitric oxide (NO). However, the presence of resveratrol-induced spinal cord protection against I/R injury has not been reported in the literature. The objective of this study was to evaluate the effects of resveratrol on neurologic functions, histopathologic changes, and NO metabolism following temporary spinal cord ischemia (SCI) in rabbits. Material and methods SCI was induced with occlusion of the infrarenal aorta in rabbits. In addition to the sham group (group S, n = 7), group C (n = 7) received vehicle 30 minutes before ischemia. Group R1 (n = 7) and R10 (n = 7) received 1 mg/kg and 10 mg/kg resveratrol instead of vehicle, respectively. Blood samples were taken to obtain nitrite/nitrate levels during the surgical procedure. After neurologic evaluation at the 48th hour of reperfusion, lumbar spinal cords were removed for histopathologic examination and malondialdehyde measurement as a marker of oxidative stress.
RESULTS
Five animals in group C had paraplegia while 5 in group R10 had normal neurologic functions. The average Tarlov score of group R10 was significantly higher than that the score of group C (4.1 +/- 1.2, vs 1.2 +/- 2.2; P =.014). Histopathologic examination revealed higher neuronal viability index in group R10 compared with that of group C (0.82 +/- 0.24 vs. 0.46 +/- 0.34; P =.018). Nitrite/nitrate levels decreased in group C (from 357 +/- 20.15 micromol/L to 281 +/- 47.9 micromol/L; P <.01) whereas they increased both in group R1 and group R10 (from 287+/-28 micromol/L to 310 +/- 33.9 micromol/L and from 296 +/- 106 micromol/L to 339 +/- 87 micromol/L, respectively) during SCI. Malondialdehyde levels of group R10 was lower than those of group C (55 +/- 12.9 nmol/mg protein vs 83.9 +/- 15.1 nmol/mg protein; P =.001, respectively).
CONCLUSIONS
In this model of SCI, resveratrol decreased oxidative stress, increased NO release, and protected spinal cord from I/R injury. Resveratrol-induced neuroprotection is probably mediated by its antioxidant and NO promoting properties. Before considering the clinical use of this natural antioxidant, further research is warranted about its mechanism of effects, timing, and optimum dose.
CLINICAL RELEVANCE
Paraplegia that results from spinal cord ischemia is a catastrophic complication of thoracic and thoracoabdominal aorta surgical procedures. Despite several surgical modifications and pharmacologic approaches, paraplegia has not been totally eliminated. On clinical grounds, the efficiency of currently used pharmacologic agents to prevent spinal cord injury during thoracic and thoracoabdominal aorta surgery is very limited and their benefit is controversial. Preischemic infusion of resveratrol protects the spinal cord from ischemia reperfusion injury in rabbits. Following clarification of the underlying protective mechanism, optimal dose, and timing, resveratrol may used in humans as an adjunct to eliminate this catastrophic complication.
Topics: Animals; Antioxidants; Flavonoids; Free Radical Scavengers; Male; Neuroprotective Agents; Nitric Oxide; Oxidative Stress; Paraplegia; Phenols; Polyphenols; Rabbits; Reperfusion Injury; Resveratrol; Spinal Cord; Spinal Cord Ischemia; Stilbenes; Wine
PubMed: 15218474
DOI: 10.1016/j.jvs.2004.03.032 -
World Journal of Gastroenterology Jan 2005To investigate the potential oxidative stress in children with chronic constipation and to explore its mechanisms.
AIM
To investigate the potential oxidative stress in children with chronic constipation and to explore its mechanisms.
METHODS
Seventy children with chronic constipation and 70 age- and sex-matched healthy children were enrolled in a randomized controlled study. Plasma levels of vitamins C and E, activities of superoxide dismutase and catalase and lipoperoxide level in erythrocytes were determined by spectrophotometry.
RESULTS
Compared with healthy children whose vitamin C, vitamin E, superoxide dismutase, catalase and lipoperoxide were 58.35+/-14.42 micromol/L, 27.15+/-6.55 micromol/L, 2 206+/-171 U/(g.Hb), 327.3+/-82.2 K/(g.Hb) and 19.18+/-4.27 nmol/(g.Hb) respectively, the levels of vitamin C, vitamin E, the activity of superoxide dismutase, and catalase in the children with chronic constipation significantly decreased [46.59+/-11.51 micromol/L, 20.65+/-4.80 micromol/L, 1943+/-147 U/(g.Hb) and 269.3+/-67.8 K/(g.Hb), respectively P<0.01], while the lipoperoxide significantly increased [25.22+/-5.01 nmol/(g.Hb), P<0.01]. With a prolonged course of disease, the levels of vitamin C, vitamin E, the activity of superoxide dismutase and catalase in the children with chronic constipation gradually decreased, while the level of lipoperoxide gradually increased.
CONCLUSION
Chronic constipation can cause potential oxidative stress in children.
Topics: Adolescent; Ascorbic Acid; Case-Control Studies; Catalase; Child; Chronic Disease; Constipation; Erythrocytes; Female; Humans; Lipid Peroxides; Male; Oxidative Stress; Superoxide Dismutase; Vitamin E
PubMed: 15637746
DOI: 10.3748/wjg.v11.i3.368 -
Radiology Aug 2010To investigate the potential role of optical tomography in the near-infrared (NIR) spectrum with ultrasonographic (US) localization as a means of differentiating...
PURPOSE
To investigate the potential role of optical tomography in the near-infrared (NIR) spectrum with ultrasonographic (US) localization as a means of differentiating early-stage cancers from benign lesions of the breast.
MATERIALS AND METHODS
The protocol was approved by the institutional review boards and was HIPAA compliant; all participants signed an informed consent. One hundred seventy-eight consecutive women (mean age, 52 years; range, 21-89 years) who underwent US-guided biopsy were imaged with a hand-held probe consisting of a coregistered US transducer and an NIR imager. The lesion location provided by coregistered US was used to guide optical imaging. Light absorption was measured at two optical wavelengths. From this measurement, tumor angiogenesis was assessed on the basis of calculated total hemoglobin concentration (tHb) and was correlated with core biopsy results. For patients diagnosed with carcinomas and followed up with subsequent excision, the tHb was correlated with pathologic parameters.
RESULTS
There were two in situ carcinomas (Tis), 35 T1 carcinomas, 24 T2-T4 carcinomas, and 114 benign lesions. The mean maximum and mean average tHb of the Tis-T1 group were 102.0 micromol/L +/- 28.5 (standard deviation) and 71.9 micromol/L +/- 18.8, and those of the T2-T4 group were 100.3 micromol/L +/- 26.4 and 67.0 micromol/L +/- 18.3, respectively. The mean maximum and mean average tHb of the benign group were 55.1 micromol/L +/- 22.7 and 39.1 micromol/L +/- 14.9, respectively. Both mean maximum and mean average tHb levels were significantly higher in the malignant groups than they were in the benign group (P < .001). The sensitivity, specificity, positive predictive value, and negative predictive value for Tis-T1 cancers were 92%, 93%, 81%, and 97%. The corresponding values for T2-T4 tumors were 75%, 93%, 69%, and 95%.
CONCLUSION
The angiogenesis (tHb) contrast imaged by using the NIR technique with US holds promise as an adjunct to mammography and US for distinguishing early-stage invasive breast cancers from benign lesions.
Topics: Adult; Aged; Aged, 80 and over; Breast Neoplasms; Feasibility Studies; Female; Humans; Middle Aged; Neoplasm Invasiveness; Neoplasm Staging; Reproducibility of Results; Sensitivity and Specificity; Subtraction Technique; Tomography, Optical; Ultrasonography, Mammary
PubMed: 20571122
DOI: 10.1148/radiol.10091237 -
Acta Pharmacologica Sinica May 2004To investigate the effects of copper-aspirin complex on rat thrombosis and the interaction between platelets and neutrophils.
AIM
To investigate the effects of copper-aspirin complex on rat thrombosis and the interaction between platelets and neutrophils.
METHODS
The model of electrically stimulated carotid artery thrombosis in Sprague Dawley rats was used; the effects of copper-aspirin complex on rat platelet-neutrophil adhesion and platelet aggregation stimulated by activated neutrophils were observed by rosette assay and Born's method, respectively.
RESULTS
Intragastric copper-aspirin complex (5, 7, and 10 mg/kg) dose-dependently prolonged the occlusion time; it significantly decreased the rosette number formed between thrombin-activated platelets and neutrophils; the 50 % of inhibitory concentration (IC50) was (54.6+/-4.3) micromol/L. Copper-aspirin complex markedly inhibited rat platelet aggregation induced by either cell free supernatant of activated neutrophils or by activated neutrophil suspension. The values of IC50 were (224.5+/-16.2) micromol/L and (820.5+/-21.4) micromol/L, whereas aspirin had no influence.
CONCLUSION
Copper-aspirin complex inhibited platelet-neutrophil interactions through a different property from aspirin and resulted in a more potent antithrombotic activity.
Topics: Animals; Aspirin; Blood Platelets; Carotid Artery Thrombosis; Cell Adhesion; Copper; Drug Combinations; Male; Neutrophils; Platelet Adhesiveness; Platelet Aggregation; Rats; Rats, Sprague-Dawley
PubMed: 15132821
DOI: No ID Found -
American Journal of Physiology.... Jun 2006Strong inward rectifier potassium channels are expressed by some vascular smooth muscle cells and facilitate K+-induced hyperpolarization. Using whole cell patch clamp...
Strong inward rectifier potassium channels are expressed by some vascular smooth muscle cells and facilitate K+-induced hyperpolarization. Using whole cell patch clamp of isolated descending vasa recta (DVR), we tested whether strong inward rectifier K+ currents are present in smooth muscle and pericytes. Increasing extracellular K+ from 5 to 50 and 140 mmol/l induced inward rectifying currents. Those currents were Ba2+ sensitive and reversed at the K+ equilibrium potential imposed by the electrode and extracellular buffers. Ba2+ binding constants in symmetrical K+ varied between 0.24 and 24 micromol/l at -150 and -20 mV, respectively. Ba2+ blockade was time and voltage dependent. Extracellular Cs+ also blocked the inward currents with binding constants between 268 and 4,938 micromol/l at -150 and -50 mV, respectively. Ba2+ (30 micromol/l) and ouabain (1 mmol/l) depolarized pericytes by an average of 11 and 24 mV, respectively. Elevation of extracellular K+ from 5 to 10 mmol/l hyperpolarized pericytes by 6 mV. That hyperpolarization was reversed by Ba2+ (30 micromol/l). We conclude that strong inward rectifier K+ channels and Na+-K+-ATPase contribute to resting potential and that KIR channels can mediate K+-induced hyperpolarization of DVR pericytes.
Topics: Animals; Barium; Capillaries; Cesium; Electrophysiology; In Vitro Techniques; Kidney Medulla; Membrane Potentials; Ouabain; Patch-Clamp Techniques; Pericytes; Potassium; Potassium Channels, Inwardly Rectifying; Rats; Rats, Sprague-Dawley
PubMed: 16439665
DOI: 10.1152/ajpregu.00877.2005 -
Journal of Dairy Science Feb 2009Data from 1,010 lactating lactating, predominately component-fed Holstein cattle from 25 predominately tie-stall dairy farms in southwest Ontario were used to identify...
Data from 1,010 lactating lactating, predominately component-fed Holstein cattle from 25 predominately tie-stall dairy farms in southwest Ontario were used to identify objective thresholds for defining hyperketonemia in lactating dairy cattle based on negative impacts on cow health, milk production, or both. Serum samples obtained during wk 1 and 2 postpartum and analyzed for beta-hydroxybutyrate (BHBA) concentrations that were used in analysis. Data were time-ordered so that the serum samples were obtained at least 1 d before the disease or milk recording events. Serum BHBA cutpoints were constructed at 200 micromol/L intervals between 600 and 2,000 micromol/L. Critical cutpoints for the health analysis were determined based on the threshold having the greatest sum of sensitivity and specificity for predicting the disease occurrence. For the production outcomes, models for first test day milk yield, milk fat, and milk protein percentage were constructed including covariates of parity, precalving body condition score, season of calving, test day linear score, and the random effect of herd. Each cutpoint was tested in these models to determine the threshold with the greatest impact and least risk of a type 1 error. Serum BHBA concentrations at or above 1,200 micromol/L in the first week following calving were associated with increased risks of subsequent displaced abomasum [odds ratio (OR) = 2.60] and metritis (OR = 3.35), whereas the critical threshold of BHBA in wk 2 postpartum on the risk of abomasal displacement was >or=1,800 micromol/L (OR = 6.22). The best threshold for predicting subsequent risk of clinical ketosis from serum obtained during wk 1 and wk 2 postpartum was 1,400 micromol/L of BHBA (OR = 4.25 and 5.98, respectively). There was no association between clinical mastitis and elevated serum BHBA in wk 1 or 2 postpartum, and there was no association between wk 2 BHBA and risk of metritis. Greater serum BHBA measured during the first and second week postcalving were associated with less milk yield, greater milk fat percentage, and less milk protein percentage on the first Dairy Herd Improvement test day of lactation. Impacts on first Dairy Herd Improvement test milk yield began at BHBA >or=1,200 micromol/L for wk 1 samples and >or=1,400 micromol/L for wk 2 samples. The greatest impact on yield occurred at 1,400 micromol/L (-1.88 kg/d) and 2,000 micromol/L (-3.3 kg/d) for sera from the first and second week postcalving, respectively. Hyperketonemia can be defined at 1,400 micromol/L of BHBA and in the first 2 wk postpartum increases disease risk and results in substantial loss of milk yield in early lactation.
Topics: 3-Hydroxybutyric Acid; Abomasum; Animals; Cattle; Cattle Diseases; Dairying; Endometriosis; Energy Metabolism; Female; Health Status; Ionophores; Ketone Bodies; Ketosis; Lactation; Least-Squares Analysis; Logistic Models; Monensin; Stomach Diseases; Time Factors
PubMed: 19164667
DOI: 10.3168/jds.2008-1507 -
The Journal of Nutrition Sep 2006Iron deficiency is prevalent in children and infants worldwide. Zinc deficiency may be prevalent, but data are lacking. Both iron and zinc deficiency negatively affect... (Randomized Controlled Trial)
Randomized Controlled Trial
Iron and zinc supplementation improved iron and zinc status, but not physical growth, of apparently healthy, breast-fed infants in rural communities of northeast Thailand.
Iron deficiency is prevalent in children and infants worldwide. Zinc deficiency may be prevalent, but data are lacking. Both iron and zinc deficiency negatively affect growth and psychomotor development. Combined iron and zinc supplementation might be beneficial, but the potential interactions need to be verified. In a randomized, placebo-controlled trial using 2 x 2 factorial design, 609 Thai infants aged 4-6 mo were supplemented daily with 10 mg of iron and/or 10 mg of zinc for 6 mo to investigate effects and interactions on micronutrient status and growth. Iron supplementation alone increased hemoglobin and ferritin concentrations more than iron and zinc combined. Anemia prevalence was significantly lower in infants receiving only iron than in infants receiving iron and zinc combined. Baseline iron deficiency was very low, and iron deficiency anemia was almost nil. After supplementation, prevalence of iron deficiency and iron deficiency anemia were significantly higher in infants receiving placebo and zinc than in those receiving iron or iron and zinc. Serum zinc was higher in infants receiving zinc (16.7 +/- 5.2 micromol/L), iron and zinc (12.1 +/- 3.8 micromol/L) or iron alone (11.5 +/- 2.5 micromol/L) than in the placebo group (9.8 +/- 1.9 micromol/L). Iron and zinc interacted to affect iron and zinc status, but not hemoglobin. Iron supplementation had a small but significant effect on ponderal growth, whereas zinc supplementation did not. To conclude, in Thai infants, iron supplementation improved hemoglobin, iron status, and ponderal growth, whereas zinc supplementation improved zinc status. Overall, for infants, combined iron and zinc supplementation is preferable to iron or zinc supplementation alone.
Topics: Anemia, Iron-Deficiency; Breast Feeding; Dietary Supplements; Ferritins; Growth; Hemoglobins; Humans; Infant; Infant Nutritional Physiological Phenomena; Iron Deficiencies; Iron, Dietary; Nutritional Status; Placebos; Rural Population; Thailand; Zinc
PubMed: 16920862
DOI: 10.1093/jn/136.9.2405 -
World Journal of Gastroenterology Feb 2006To characterize H+ and HCO3- transporters in polarized CFPAC-1 human pancreatic duct cells, which were derived from a cystic fibrosis patient with the DeltaF508 CFTR...
AIM
To characterize H+ and HCO3- transporters in polarized CFPAC-1 human pancreatic duct cells, which were derived from a cystic fibrosis patient with the DeltaF508 CFTR mutation.
METHODS
CFPAC-1 cells were seeded at high density onto permeable supports and grown to confluence. The cells were loaded with the pH-sensitive fluorescent dye BCECF, and mounted into a perfusion chamber, which allowed the simultaneous perfusion of the basolateral and apical membranes. Transmembrane base flux was calculated from the changes in intracellular pH and the buffering capacity of the cells.
RESULTS
Our results showed differential permeability to HCO3-/CO2 at the apical and basolateral membranes of CFPAC-1 cells. Na+/ HCO3- co-transporters (NBCs) and Cl-/ HCO3- exchangers (AEs) were present on the basolateral membrane, and Na+/H+ exchangers (NHEs) on both the apical and basolateral membranes of the cells. Basolateral HCO3- uptake was sensitive to variations of extracellular K+ concentration, the membrane permeable carbonic anhydrase (CA) inhibitors acetazolamide (100 micromol/L) and ethoxyzolamide (100 micromol/L), and was partially inhibited by H2-DIDS (600 micromol/L). The membrane-impermeable CA inhibitor 1-N-(4-sulfamoylphenylethyl)-2,4,6-trimethylpyridine perchlorate did not have any effect on HCO3- uptake. The basolateral AE had a much higher activity than that in the apical membrane, whereas there was no such difference with the NHE under resting conditions. Also, 10 micromol/L forskolin did not significantly influence Cl-/ HCO3- exchange on the apical and basolateral membranes. The administration of 250 micromol/L H2-DIDS significantly inhibited the basolateral AE. Amiloride (300 micromol/L) completely inhibited NHEs on both membranes of the cells. RT-PCR revealed the expression of pNBC1, AE2, and NHE1 mRNA.
CONCLUSION
These data suggest that apart from the lack of CFTR and apical Cl-/ HCO3- exchanger activity, CFPAC-1 cells express similar H+ and HCO3- transporters to those observed in native animal tissue.
Topics: 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; Acetazolamide; Anion Transport Proteins; Bicarbonates; Cell Line; Cell Membrane Permeability; Ethoxzolamide; Humans; Hydrogen-Ion Concentration; Pancreatic Ducts; Potassium
PubMed: 16521216
DOI: 10.3748/wjg.v12.i6.885