The effects of hepatic steatosis on thromboxane A2 induced portal hypertension.

INTRODUCTION AND AIM: Thromboxane (TX) A2 was identified as an important vasoconstrictor during Zymosan induced portal perfusion pressure (PP) increase. We aimed at investigating whether hepatic steatosis influences the extent of TXA2-induced portal hypertension. MATERIALS AND METHODS: Sprague-Dawley rats were randomly divided into control and steatosis (induced by the special diet) groups. PP and TXB2 (stable degradation product of TXA2) in the perfusate were measured after in situ liver perfusion with Zymosan (150µg/ml, 40-46min) or U46619 (TXA2 analog, 0.1µM/ml, 40-46min). The number of Kupffer cell (KC) was measured by immunohistochemistry with CD163. RESULTS: Zymosan induced more TXB2 production and a higher PP increase in control group than in steatosis group despite more CD163 positive KCs in fatty livers. PP and TXB2 efflux revealed a strong correlation in control group and a moderate correlation in steatosis group. Contrary to the effect of Zymosan, U46619 induced a much higher PP increase in steatosis group than in control group. CONCLUSION: Severe steatosis increased number of KCs, however, PP increase and TXB2 efflux caused by Zymosan infusion in fatty livers were lower than those in healthy livers. In contrast, TXA2 analog caused higher PP increase in fatty livers. Targeting the more sensitive response to TXA2 in fatty livers might be a potential therapy of severe steatosis.

[The imbalance of vasoactive components and arachidonic acid in the placenta and amniotic fluid in preeclampsia]. / Disbalans vazoaktivnykh komponentov i arakhidonovoi kisloty v platsente i okoloplodnykh vodakh pri preéklampsii.

The content of vasoactive compounds and arachidonic acid in the placenta and amniotic fluid was studied in full-term (39-40 weeks) physiological pregnancy and preeclampsia (PE). The content of metabolites of nitric oxide (NOx), endothelin-1, thromboxane B2 (TxB2), prostacycline (PGI2) and arachidonic acid was estimated using spectrophotometric, immunoenzyme methods and gas-liquid chromatography. It was found that in PE the content of vasoconstrictors, of endothelin and TxB2, increased in the placenta and amniotic fluid, while the content of vasodilators, PGI2 and NOx decreased. Despite the same directionality of changes in both studied objects, the degree of changes differed and was more pronounced in the placenta. A direct or inverse correlative relationship was found between various vasoactive components (depending on their effect on vascular tone). In the case of arachidonic acid changes in its content in PE correlated with the level of vasoactive compounds, the source of which it is. The revealed differences in the ratio of vasoactive components obviously play a pathogenetic role in the development of PE and its subsequent complications.

Immature platelets and antiplatelet therapy response to aspirin in Kawasaki disease.

INTRODUCTION: Kawasaki disease is a kind of systemic vasculitis that mainly damages moderate and small-sized blood vessels, and is a leading cause of coronary artery lesions (CAL). Antiplatelet therapy is a routine component of Kawasaki disease treatment strategies. So it is important to evaluate the antiplatelet effect of aspirin because of the individual biological variability of antiplatelet effect of aspirin. The immature platelet fraction (IPF) has attracted particular attention as it may influence the antiplatelet effect of aspirin. This study investigated the prognostic factors for evaluating the degree of vasculitis and the effect of antiplatelet therapy in children with Kawasaki disease. MATERIALS AND METHODS: Blood samples were collected from 44 patients with Kawasaki disease before aspirin treatment and 7 to 10 days after treatment. The IPF counts, percentage of the IPF, and highly fluorescent IPF were detected by a Sysmex XE-5000 instrument. The levels of 11-dehydrothromboxane B2 (11-DH-TXB2), soluble CD40 ligand (sCD40L), and soluble P-selectin (sP-selectin) were measured by ELISA. The correlation between the measured factors and the degree of coronary artery damage in Kawasaki disease was analyzed. RESULTS: We found that 11-DH-TXB2, sP-selectin, and sCD40L levels were much more elevated in the CAL group than in the non-coronary artery lesions (NCAL) group before aspirin treatment. The concentrations of 11-DH-TXB2, sCD40L, sP-selectin, and IPF were reduced after aspirin treatment in the NCAL group but not the CAL group. This is related to the degree of coronary artery damage in Kawasaki disease patients. Additionally, 11-DH-TXB2, sCD40L, sP-selectin, and IPF were positively correlated with the degree of coronary artery damage in Kawasaki disease patients. CONCLUSION: The current study suggests that the presence of high plasma concentrations of 11-DH-TXB2, sCD40L, sP-selectin, and IPF can be considered a risk factor and experimental biomarker for CAL in Kawasaki disease patients.

Antithrombotic components of Malus halliana Koehne flowers.

Flowers of Malus halliana (M. halliana) Koehne have been used as a Chinese traditional medicine to treat metrorrhagia and in our study, its chemical composition and anticoagulant effect were investigated. Five compounds were isolated and identified from M. halliana flowers, including limocitrin-3-O-glucoside (1), baohuoside Ⅱ (2), kaempferol-3-O-α-L-furan arabinoside (3), phloretin-4'-O-glycosidase (4) and afzeloside (5). Compound 1-3 were isolated for the first time from this genus. The anticoagulant effect of the compounds and extracts of M. halliana flowers were evaluated by APTT, PT, TT and FIB on plasma of rabbit in vitro. The results indicated that several fractions of M. halliana flowers and compounds 2-5 exhibited anticoagulant activity in vitro. Subsequently, afzeloside (5), the abundant component in M. halliana flowers, was investigated further for its antithrombotic effect in vivo and its antithrombotic mechanisms were evaluated on rats acute blood-stasis model. The antithrombotic effect was evaluated by WBV, PV, HCT, ESR, APTT, PT, TT, FIB, 6-keto-PGF1α, TXB2, ET-1 and eNOS in vivo. Afzeloside demonstrated inhibitory effect of thrombus formation, and its underlying antithrombotic mechanism was found to be related to the regulation of vascular endothelium active substance, activating blood flow and anticoagulant effect. Hence, we postulate that flavonoids may be the active ingredients of the plant.

Anti- Versus Pro-Inflammatory Metabololipidome Upon Cupping Treatment.

BACKGROUND/AIMS: This study aimed to explore the metabololipidome in mice upon cupping treatment. METHODS: A nude mouse model mimicking the cupping treatment in humans was established by administrating four cupping sets on the back skin for 15 minutes. UPLC-MS/ MS was performed to determine the PUFA metabolome in mice skin and blood before and after cupping treatment. The significantly changed lipids were administered in macrophages to assess the production of pro-inflammatory cytokines IL-6 and TNF-α by ELISA. RESULTS: The anti-inflammatory lipids, e.g. PGE1, 5,6-EET, 14,15-EET, 10S,17S-DiHDoHE, 17R-RvD1, RvD5 and 14S-HDoHE were significantly increased while pro-inflammatory lipids, e.g. 12-HETE and TXB2 were deceased in the skin or plasma post cupping treatment. Cupping treatment reversed the LPS-stimulated IL-6 and TNF-α expression in mouse peritoneal exudates. Moreover, 5,6-EET, PGE1 decreased the level of TNF-α, while 5,6-EET, 5,6-DHET downregulated IL-6 production in macrophages. Importantly, 14,15-EET and 14S-HDoHE inhibited both IL-6 and TNF-α induced by lipopolysaccharide (LPS). 17-RvD1, RvD5 and PGE1 significantly reduced the LPS-initiated TNF-α, while TXB2 and 12-HETE further upregulated the LPS-enhanced IL-6 and TNF-α expression in macrophages. CONCLUSION: Our results reveal the identities of anti-inflammatory versus pro-inflammatory metabolipidome and suggest the potential therapeutic mechanism of cupping treatment.

High Ratios of C20:4n-6/C20:5n-3 and Thromboxane B2 /6-Keto-Prostaglandin F1α in Placenta Are Potential Risk Contributors for Neural Tube Defects: A Case-Control Study in Shanxi Province, China.

BACKGROUND: Neural tube defects (NTDs) are severe congenital malformations. Folate supplementation can reduce the risk, but cannot prevent all NTDs, suggesting other reasons for folate-resistant NTDs. The present study assesses placental fatty acid composition, eicosanoids, and cytokines as risk factors for NTDs in a Chinese population with highly incident NTDs. METHODS: Seventy-seven aborted fetuses with NTDs during the third trimester were cases and 142 healthy newborns were controls. Placental fatty acid composition, eicosanoids, and cytokines were determined by standard methods. RESULTS: The placental C20:4n-6/C20:5n-3 and thromboxane B2 (TXB2 )/6-keto-prostaglandin F1α (6-keto-PGF1α ) ratios were significantly higher for cases than controls (p < 0.001 and 0.05, respectively). For the top versus the lowest tertiles of placental C20:4n-6/C20:5n-3 and TXB2 /6-keto-PGF1α , odds ratios for NTD occurrence were 3.79 (95% confidence interval, 1.60-8.96) (p for trend < 0.01) and 5.52 (95% confidence interval, 2.07-14.74) (p for trend < 0.001), respectively, adjusted for fetal sex as well as maternal age, occupation, parity, smoking, passive smoking, periconceptional folate supplementation, conception season, and tea drinking. The C20:4n-6/C20:5n-3 and TXB2 /6-keto-PGF1α ratios were positively correlated (r = 0.14; p < 0.05). The proportions of C18:2n-6, C18:3n-6, C20:3n-6, C18:3n-3, C20:3n-3, C20:5n-3, and C22:5n-3 were significantly lower in cases than controls, and all negatively associated with NTD occurrence (tertile-specific odds ratios); after adjustment for the potential confounders, these associations remained significant (p for trend < 0.05) except for C20:3n-3. CONCLUSION: High placental ratios of C20:4n-6/C20:5n-3 and TXB2 /6-keto-PGF1α are risk factors for neural tube defects.Birth Defects Research 109:550-563, 2017.© 2017 Wiley Periodicals, Inc.

Liquid chromatography-tandem mass spectrometry for simultaneous measurement of thromboxane B2 and 12(S)-hydroxyeicosatetraenoic acid in serum.

Arachidonic acid (AA) is metabolized in human platelets by two main pathways: via cyclooxygenase (COX-1) to prostaglandins and thromboxane (TX)A2 and via 12-lipoxygenase (12-LOX) to 12(S)-hydroxyeicosatetraenoic acid (12(S)-HETE). While COX products are known to regulate platelet reactivity, the role of 12-LOX metabolites is still controversial. To better understand the platelet enzymatic pathways, we developed a simple and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for the simultaneous measurement of both platelet metabolites in human serum. After the addition of deuterated d4-TXB2 and d8-12(S)-HETE as internal standards and the solid-phase extraction of serum samples, analytes were resolved using reversed-phase C18 column and quantified using negative ion electrospray ionization-tandem mass spectrometry. Intra and interassay imprecisions were less than 10% for both analytes. The lower limits of quantification were 0.244ng/ml and 0.976ng/ml for TXB2 and 12(S)-HETE, respectively. This method was applied to measure platelet metabolites in healthy subjects (n=35). LC-MS/MS allows rapid, simultaneous, sensitive and accurate quantification of both platelet AA products in human serum with a small sample volume required and a minimal sample preparation.

The effect of tramadol and indomethacin coadministration on gastric barrier function in dogs.

BACKGROUND: Tramadol is a centrally acting analgesic that is often used in conjunction with nonsteroidal anti-inflammatory drugs (NSAIDs). The effect of coadministration of tramadol and indomethacin on gastric barrier function in dogs is unknown. HYPOTHESIS/OBJECTIVES: That coadministration of a nonselective NSAID (indomethacin) and tramadol would decrease recovery of barrier function as compared with acid-injured, indomethacin-treated, and tramadol-treated mucosa. ANIMALS: Gastric mucosa of 10 humanely euthanized shelter dogs. METHODS: Ex vivo study. Mounted gastric mucosa was treated with indomethacin, tramadol, or both. Gastric barrier function, prostanoid production, and cyclooxygenase expression were quantified. RESULTS: Indomethacin decreased recovery of transepithelial electrical resistance after injury, although neither tramadol nor the coadministration of the two had an additional effect. Indomethacin inhibited production of gastroprotective prostanoids prostaglandin E2 (acid-injured PGE2 : 509.3 ± 158.3 pg/mL, indomethacin + acid injury PGE2 : 182.9 ± 93.8 pg/mL, P < .001) and thromboxane B2 (acid-injured TXB2 : 233.2 ± 90.7 pg/mL, indomethacin + acid injury TXB2 : 37.9 ± 16.8 pg/mL, P < .001), whereas tramadol had no significant effect (PGE2 P = .713, TXB2 P = .194). Neither drug had an effect on cyclooxygenase expression (COX-1 P = .743, COX-2 P = .705). Acid injury induced moderate to marked epithelial cell sloughing, which was unchanged by drug administration. CONCLUSIONS AND CLINICAL IMPORTANCE: There was no apparent interaction of tramadol and a nonselective cyclooxygenase in this ex vivo model. These results suggest that if there is an adverse interaction of the 2 drugs in vivo, it is unlikely to be via prostanoid inhibition.

In vivo hemostatic efficacy of polyurethane foam compared to collagen and gelatin.

OBJECTIVES: Topical hemostatic agents are used in all surgical disciplines. Most of these hemostats are based on animal-derived products like collagen and gelatin. They carry the potential risk of pathogen transmission. A newly developed biodegradable, fully synthetic hemostatic agent based on polyurethane foam (PU) with 55 % polyethylene glycol (PEG) would prevent these potential risks. MATERIALS AND METHODS: The hemostatic efficacy of this new agent was compared to gelatin and collagen in humans who underwent extraction of an upper and lower molar (split-mouth model). After extraction of a molar in the maxilla and mandible, a PU foam and collagen or gelatin were inserted in the extraction socket for 2 min. Hereafter, the agents were removed and stored in ethylenediaminetetraacetic acid to stop coagulation. Then, the concentration of coagulation parameters thrombin-antithrombin III (TAT) complexes, fibrinogen, and thromboxane B2 (TxB2) in blood extracts from the agents was measured. The concentrations were also determined in baseline blood samples which were collected from the extraction socket. RESULTS: The concentrations of TAT and TxB2 were significantly increased, and fibrinogen concentration was significantly reduced compared to baseline wound blood concentrations indicating enhanced hemostasis. No significant differences were seen in the concentrations of these coagulation parameters in the three different hemostatic agents. CONCLUSIONS: These results show that PU combined with 55 % PEG is a promising alternative for the animal-derived hemostatic agents. CLINICAL RELEVANCE: The synthetic hemostatic agent could replace the animal-derived products like collagen and gelatin and therewith prevent the potential risk of pathogen transmission.

Quantification of intracellular and extracellular prostanoids stimulated by A23187 by liquid chromatography/electrospray ionization tandem mass spectrometry.

Prostanoids are bioactive substances that contribute to various biological and pathological processes. To evaluate both extracellular and intracellular levels of prostanoids at the same time, we developed methods for quantification of extracellular and intracellular levels of prostanoids, including prostaglandin E(2) (PGE(2)), PGD(2), PGF(2α), 6-keto PGF(1α), and TXB(2), in cultured cells using liquid chromatography/tandem mass spectrometry (LC/MS/MS), and we validated the LC/MS/MS methods. A solid-phase extraction cartridge was used for extraction of prostanoids. The prostanoids were separated by a C(18) column with an isocratic flow of acetonitrile/water/acetic acid (40:60:0.1, v/v/v). Calibration curves of extracellular measurement for the prostanoids were linear in the range from 0.1 to 100 ng/mL (r(2)>0.999), and those of intracellular measurement were linear in the range from 0.05 to 50 ng (r(2)>0.999). Validation assessment showed that both methods of extracellular and intracellular measurements were highly reliable with good accuracy and precision. We also applied the methods to human airway epithelial Calu-3 cells and human lung adenocarcinoma epithelial A549 cells.

Aspirin treatment influences platelet-related inflammatory biomarkers in healthy individuals but not in acute stroke patients.

OBJECTIVES: Platelet-leukocyte aggregation is believed to contribute to acute thrombotic events. While the effect of aspirin on platelet-to-platelet aggregation is well established, the impact of the drug on pro-inflammatory platelet function remains equivocal. Thus we investigated the effect of aspirin on selected platelet-related inflammatory biomarkers in both acute ischaemic stroke patients and healthy volunteers. METHODS: Using five-colour flow cytometry the platelet surface expression of CD62P and CD40L and subpopulations of leukocyte-platelet aggregates were assessed in 63 acute stroke patients and 40 healthy volunteers at baseline and after a 10-day period of aspirin intake at a daily dose of 150 mg. Simultaneously the plasma levels of soluble CD62P and CD40L, serum level of TxB(2), and whole blood impedance platelet aggregation under arachidonic acid (AA) stimulation were investigated. RESULTS: No differences in values of studied platelet-related inflammatory biomarkers in both resting platelets and those activated with TRAP after 10-day treatment with aspirin were confirmed in stroke subjects. In healthy individuals the resting platelet expression of CD62P, plasma level of soluble CD62P and percentage of circulating monocyte-platelet aggregates were lower after the aspirin intake period (P=0.009; P=0.04; P=0.004, respectively). In both studied groups serum level of TxB(2) and platelet aggregation under AA stimulation were lower than before treatment (P<0.001). CONCLUSION: Despite effective inhibition of COX-1-dependent platelet aggregation, aspirin does not influence the platelet α-granule-derived inflammatory mediators and monocyte-platelet aggregation in acute stroke subjects, although it does in healthy individuals.

Comparison of UHPLC and HPLC methods for the assay of prostanoids: "are the methods equivalent in terms of accuracy and precision?".

BACKGROUND: As new methods are developed to increase efficiency and higher analytical performance, it is necessary to evaluate their quality in comparison to standard methods. To understand how the analytical performance changes between methods, it is common to compare the validation parameters; sensitivity, linearity, accuracy and precision. Here, we compare an UHPLC-UV method to the HPLC-UV method (reference method) for the simultaneous determination of seven prostanoids. Though the basic chromatography theory is the same for HPLC and UHPLC, the instrumentation has been modified to accommodate higher pressures, lower flow rates and smaller sample size. The differences in analytical instrumentation and procedures can give rise to method inequivalencies. Our approach evaluates the UHPLC and HPLC methods and poses the question: are the methods equivalent? To answer this question a statistical comparison of the analytical performance and method parameters is necessary. RESULTS: Statistical comparisons were performed using the t-test, F-test, regression analyses (ordinary linear regression and Deming regression) and Bland-Altman analyses. Statistical comparison of the results, suggested that the precision (amount of variability) is different (p < 0.05) for the HPLC and UHPLC methods. Whereas, the accuracy (method bias and the means) is similar (p > 0.05) for 8-isoprostane, 11-dehydro TXB2, PGE2 PGF(2α), PGD2 and 15-deoxy Δ¹²,¹4 PGJ2. DISCUSSION: Ordinary linear regression shows that the methods are well correlated for all compounds. The Deming regression, which assumes error in both the methods, suggests the existence of a proportional and constant bias for 11-dehydro TXB2 and only proportional bias for 8-isoprostane, PGF(2α), PGD2 and 15-deoxy Δ(12,14) PGJ2 between the two methods. According to Deming regression, the two methods are statistically similar for 6-keto PGF(1α) and PGE2. The Bland-Altman analyses indicate the two methods are commutable.

Improved sensitivity mass spectrometric detection of eicosanoids by charge reversal derivatization.

Combined liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) is a powerful method for the analysis of oxygenated metabolites of polyunsaturated fatty acids including eicosanoids. Here we describe the synthesis of a new derivatization reagent N-(4-aminomethylphenyl)pyridinium (AMPP) that can be coupled to eicosanoids via an amide linkage in quantitative yield. Conversion of the carboxylic acid of eicosanoids to a cationic AMPP amide improves sensitivity of detection by 10- to 20-fold compared to negative mode electrospray ionization detection of underivatized analytes. This charge reversal derivatization allows detection of cations rather than anions in the electrospray ionization mass spectrometer, which enhances sensitivity. Another factor is that AMPP amides undergo considerable collision-induced dissociation in the analyte portion rather than exclusively in the cationic tag portion, which allows isobaric derivatives to be distinguished by tandem mass spectrometry, and this further enhances sensitivity and specificity. This simple derivatization method allows prostaglandins, thromboxane B(2), leukotriene B(4), hydroxyeicosatetraenoic acid isomers, and arachidonic acid to be quantified in complex biological samples with limits of quantification in the 200-900 fg range. One can anticipate that the AMPP derivatization method can be extended to other carboxylic acid analytes for enhanced sensitivity detection.

Cigarette smoke exposure up-regulates endothelin receptor B in human pulmonary artery endothelial cells: molecular and functional consequences.

BACKGROUND AND PURPOSE: Pulmonary arteries from smokers and chronic obstructive pulmonary disease patients show abnormal endothelium-dependent vascular reactivity. We studied the effect of cigarette smoke extract (CSE) on endothelin receptor B (ET(B) ) expression in human pulmonary artery endothelial cells (HPAECs) and its role in endothelial dysfunction. EXPERIMENTAL APPROACH: ET(B) receptor expression was measured by real time RT-PCR, Western blot and immunofluorescence. Cell contraction, intracellular Ca(2+) , F/G-actin, RhoA activity, myosin light chain phosphorylation, ET, NO, thromboxane (Tx)A(2) and reactive oxygen species (ROS) were measured by traction microscopy, fluorescence microscopy, phalloidin fluorescence, colorimetric assay, Western blot, elisa and DCFDA fluorescence respectively. KEY RESULTS: Cigarette smoke extract dose-dependently increased ET(B) receptor expression in HPAECs after 24h incubation. CSE-induced ET(B) expression was attenuated by bosentan, the ET(B) receptor antagonist BQ788, the Rho kinase antagonist Y27632 and the antioxidant N-acetylcysteine. A monoclonal antibody to ET-1 prevented CSE-induced ET(B) receptor overexpression. Twenty-four hour exposure to ET-1 dose-dependently increased ET(B) receptor expression, mimicking the effect of CSE. CSE-induced ET(B) receptor overexpression caused greater cell contraction; increased intracellular Ca(2+) ; increased F/G-actin and RhoA activity; increased myosin light chain phosphorylation; augmented TxA(2) and ROS production; and decreased NO after acute ET-1 (10nM). These effects were attenuated by bosentan, BQ788, Y27632 and N-acetylcysteine. CONCLUSIONS AND IMPLICATION: Cigarette smoke extract induced ET(B) receptor overexpression by a feed forward mechanism mediated partly by ET release, promoting HPAEC dysfunction and attenuated by ET(B) receptor blockade, Rho kinase and ROS inhibition. These results provide support for the use of bosentan in CS-related endothelial dysfunction.

Platelet activation patterns in platelet size sub-populations: differential responses to aspirin in vitro.

Circulating platelets are heterogeneous in size and structure. Whether this translates into differences in platelet function and efficacy of antiplatelet therapy is unclear. Hence, we decided to investigate the activation patterns among different platelet populations differentiated by size, and to compare the inhibitory effects of aspirin in these populations. Circulating platelets from 9 healthy volunteers were separated by size and stratified into the largest and smallest quintiles. Platelets were stimulated with 75 µM arachidonic acid (AA), 10 µM ADP or 25 µM TRAP. Alpha-granule protein secretion and expression (P-selectin, VWF, fibrinogen), surface-protein activation (activated integrin αIIbß3) were assessed. Platelet thromboxane B(2) (TxB(2)) synthesis following AA stimulation was measured in vitro before and after incubation with 265 µM aspirin. Reticulated (juvenile) platelets were assessed using thiazole orange staining. A greater number of large platelets in the largest quintile were reticulated compared with the smallest quintile (6.1 ± 2.8% vs. 1.2 ± 1.5% respectively, p < 0.001). Larger platelets also synthesized more TxB(2) than small platelets both before (1348 ± 276 pg/mL vs. 1023 ± 214 pg/mL, respectively, p = 0.01) and after aspirin (1029 ± 190 pg/mL vs. 851 ± 159 pg/mL, respectively, p = 0.03). After stimulation with each agonist, a greater proportion of large platelets bound fibrinogen, VWF, P-selectin and activated integrin αIIbß3 than small platelets both in the presence and in the absence of in vitro aspirin. In an in vitro setting, large platelets appear to be more active than small platelets and continue to be more active even after in vitro aspirin. Platelets exhibit heterogeneity in size and structure. Whether this translates into platelet function and efficacy of antiplatelet therapy is unclear. We evaluated platelet functional properties and the effects of aspirin on separated platelet subpopulations in an in vitro setting. Platelets were sorted into the largest and smallest size quintiles using flow cytometry forward scatter. Alpha-granule protein release, dense granule content, surface protein activation and thromboxane synthesis were significantly greater in large platelets compared with small platelets, before and after stimulation with arachidonic acid, ADP and TRAP. Even after incubation with aspirin, large platelets continued to be more active than small platelets. In conclusion, large platelets are more active than small platelets and aspirin fails to eliminate these differential activation properties.

Inhibition of secretory phospholipase A2 activity attenuates lipopolysaccharide-induced acute lung injury in a mouse model.

This study evaluated the hypothesis that LY374388, an inhibitor of secretory phospholipase A(2) (sPLA(2)) activity, may exert a protective effect on lipopolysaccharide (LPS)-induced acute lung injury in male C57BL/6J mice. Intratracheal administration of LPS increased histopathological changes in lung tissue, lung wet to dry ratios, and the bronchoalveolar lavage fluid levels of neutrophil numbers, sPLA(2) activity, leukotriene B(4), and thromboxane B(2). However, a simultaneous intraperitoneal treatment with LY374388 significantly attenuated these LPS-induced changes. Thus, inhibition of sPLA(2) activity significantly attenuated the acute lung injury induced by LPS. sPLA(2) played an important role in the pathogenesis of LPS-induced acute lung injury in mice.

Preventive effect of pentoxifylline on acute radiation damage via antioxidant and anti-inflammatory pathways.

PURPOSE: The aim of the present study was to investigate whether pentoxifylline (PTX) treatment could protect against induced acute radiation enteritis. METHOD: Rats received 100 mg/kg/day PTX for 7 days before irradiation and continued on treatment for 3 days after irradiation. The intestinal myeloperoxidase (MPO) activities and malondialdehyde (MDA), glutathione (GSH), prostaglandin E2, and thromboxane B2 levels were determined. Terminal ileum tissue was evaluated for morphological changes. Also, nuclear factor kappa (NF-kappa), tumor necrosis factor-alpha (TNF-alpha), and intercellular adhesion molecule 1 (ICAM-1) expressions were analyzed with immunohistochemisty methods. RESULTS: PTX treatment was associated with increased GSH levels and decreased MPO activity and MDA, prostaglandin E2, and thromboxane B2 levels. Histopathologic examination showed that intestinal mucosal structure was preserved in the PTX-treated group while having significant decreases in NF-kappaB, TNF-a, and ICAM-1 expression. CONCLUSIONS: PTX appears to have a protective effect against radiation damage. This protective effect is mediated in part by decreasing both inflammatory reactions and oxidative stress.

Gross-total hematoma removal of hypertensive basal ganglia hemorrhages: a long-term follow-up.

BACKGROUND AND PURPOSE: Hypertensive basal ganglia hemorrhage (HBGH) accounts for 35%-44% of cases of hypertensive intracranial hemorrhage (ICH), which is one of the most devastating forms of cerebrovascular disease. In this study, intracerebral hematoma was evacuated with a burr hole craniectomy. The relationships of residue hematoma volume to brain edema, inflammation factors and the long-term prognosis of HBGH patients were studied. METHODS: One hundred and seventy-six patients with HBGH were randomly divided into gross-total removal of hematoma (GTRH) and sub-total removal of hematoma (STRH) groups. The pre-operative and post-operative data of the patients in the two groups were compared. The pre-operative data included age, sex, hematoma volume, time from the ictus to the operation, Glasgow Coma Scale (GCS) scores, and the European Stroke Scale (ESS) scores. The post-operative information included edema grade, level of thromboxane B2 (TXB2), 6-keto-prostaglandin F1a (6-K-PGF1a), tumor necrosis factor-a (TNF-a) and endothelin (ET) in hematoma drainage or cerebral spinal fluid (CSF), ESS and Barthel Index (BI). RESULTS: There was no statistical difference between the two groups (P>0.05) in the pre-operative data. The levels of TXB2, 6-K-PGF1a, TNF-a and ET in the GTRH group were significantly lower than those in the STRH group at different post-operative times. The ESS in the GTRH group increased rapidly after the operation and was higher than that in the STRH group. There was a significant difference between the two groups (P<0.05). The post-operative CT scan at different times showed that the brain edema grades were better in the GTRH group than in the STRH group. The BI was higher in the GTRH group than in the STRH group (P<0.05). CONCLUSIONS: GTRH is an effective method to decrease ICH-induced injury to brain tissue. Such effect is related to decreased perihematomal edema formation and secondary injury by coagulation end products activated inflammatory cascade.

Quantitative characterization of prostaglandins in the uterus of early pregnant cattle.

Prostaglandins (PGs) are important regulators of reproductive processes including early embryonic development. We analyzed the most relevant PG in bovine uteri at different preimplantation pregnancy stages when compared with non-pregnant controls. Additionally, endometrium and trophoblast tissues were examined regarding specific enzymes and receptors involved in PG generation and function. Simmental heifers were artificially inseminated or received seminal plasma only. At days 12, 15, or 18, post-estrus uteri were flushed for PG determination by liquid chromatography-tandem mass spectrometry. Endometrium and trophoblast tissues were sampled for RNA extraction and quantitative real-time PCR analysis. At all days and points of time examined, the concentration of 6-keto PGF(1alpha) (stable metabolite of PGI(2)) was predominant followed by PGF(2alpha)>PGE(2)>PGD(2) approximately TXB(2) (stable metabolite of TXA(2)). At days 15 and 18, PG increased from overall low levels at day 12, with a much more pronounced increase during pregnancy. The PGF(2alpha)/PGE(2) ratio was not influenced by status. The highest PG concentration was measured at day 15 with 6-keto PGF(1alpha) (6.4 ng/ml) followed by PGF(2alpha) (1.1 ng/ml) and PGE(2) (0.3 ng/ml). Minor changes in endometrial PG biosynthesis enzymes occurred due to pregnancy. Trophoblasts revealed high transcript abundance of general and specific PG synthases contributing to uterine PG. As PGI(2) and PGF(2alpha) receptors were abundantly expressed by the trophoblast, abundant amounts of PGI(2) and PGF(2alpha) in the uterine lumen point towards an essential role of PG for the developing embryo. High amounts of PG other than PGE(2) in the preimplantation uterus may be essential rather than detrimental for successful reproduction.