Contribution of cyclooxygenase-1-dependent prostacyclin synthesis to bradykinin-induced dermal extravasation.

BACKGROUND: Non-allergic angioedema is a potentially life-threatening condition caused by accumulation of bradykinin and subsequent activation of bradykinin type 2 receptors (B2). Since COX activity plays a pivotal role in B2 signaling, the aim of this study was to determine which prostaglandins are the key mediators and which COX, COX-1 or COX-2, is predominantly involved. METHODS: We used Miles assays to assess the effects of inhibitors of COX, 5-lipoxygenase, epoxyeicosatrienoic acid generation, cytosolic phospholipase A2α and a variety of prostaglandin receptor antagonists on bradykinin-induced dermal extravasation in C57BL/6 and COX-1-deficient mice (COX-1-/-). In addition, the prostacyclin metabolite 6-keto-PGF1α was quantified by ELISA in subcutaneous tissue from C57BL/6 and human dermal microvascular endothelial cells. In the latter, 6-keto-PGF1α was also quantified and identified by LC-MS/MS. RESULTS: Unspecific COX inhibition by ibuprofen and diclofenac significantly reduced B2-mediated dermal extravasation in C57BL/6 but not COX-1-/-. Likewise, inhibition of cytosolic phospholipase A2α showed similar effects. Furthermore, extravasation in COX-1-/- was generally lower than in C57BL/6. Of the prostaglandin antagonists used, only the prostacyclin receptor antagonist RO1138452 showed a significant reduction of dermal extravasation. Moreover, 6-keto-PGF1α concentrations were increased after bradykinin treatment in subcutaneous tissue from C57BL/6 as well as in human dermal microvascular endothelial cells and this increase was abolished by diclofenac. CONCLUSION: Our findings suggest that COX-1-dependent prostacyclin production is critically involved in dermal extravasation after activation of B2 in small dermal blood vessels. Targeting prostacyclin production and/or signaling appears to be a suitable option for acute treatment of non-allergic angioedema.

E-scooter driving under the acute influence of alcohol-a real-driving fitness study.

PURPOSE: To assess the effects of alcohol on the ability to drive an e-scooter, driving tests reflecting real-life situations accompanied by medical examinations focusing on balance were conducted at different blood alcohol concentrations (BACs). METHODS: Fifty-seven subjects who consumed alcohol (28 female, 29 male) and 6 consistently sober subjects (3 female, 3 male) participated in the study. Alcohol was administered on a fixed schedule, and the individual drinking quantity was individually calculated in advance using the Widmark formula. Repeated runs through a fixed course were performed. Following each ride, a blood sample was taken for BAC determination, and medical tests were performed. RESULTS: Even at low BACs (0.21-0.60 g/kg), subjects showed a significant decrease in driving performance, to approximately 60% of the initial level. Differences in driving performance at different BAC ranges were observed for different obstacles, especially for the narrowing track, gate passage, slalom, and driving in circles obstacles. Furthermore, worse Romberg and Unterberger test results were correlated with worse driving performance. It cannot be assumed that learning effects during the study had a relevant effect, as shown in the comparison of the driving performance of the alcohol-consuming group with that of the control group. Sex-specific differences were not found. DISCUSSION: Significant deteriorations in driving performance at BACs below 1.10 g/kg confirmed alcohol-related risk potential when using e-scooters. At this time, these findings may lead to the assumption of "relative driving impairment" in Germany. The Romberg and Unterberger tests could be considered a complementary investigation method for the assessment of e-scooter driving impairment. CONCLUSION: Even at rather low BACs between 0.21 and 0.40 g/kg, there was a significant deterioration in driving performance under the influence of alcohol compared to sober, which highlights the negative effects of alcohol on e-scooter driving.

Immediate results of percutaneous management of coarctation of the aorta: A 7-year single-centre experience.

BACKGROUND: Coarctation of the aorta (CoA) is often treated percutaneously. The aim of this study was to describe the immediate results of percutaneous management of native aortic coarctation (NaCoA) and recoarctation of the aorta (ReCoA) at our institution. METHODS: We identified all patients with NaCoA or ReCoA who underwent percutaneous dilatation by either balloon angioplasty (BAP) or endovascular stent implantation (ESI) between 2011 and 2017. Success was defined as a residual peak-to-peak gradient (PPG) <20 mmHg or a ≥50% reduction in the gradient if the pre-intervention PPG was <20 mmHg. RESULTS: 63 patients (median age 6.8 years, interquartile range [IQR] 0.4-14.2) were identified. Among 11 patients with NaCoA, 7 underwent BAP and 4 had ESI, and among 52 patients with ReCoA, 42 underwent BAP and 10 had ESI. In patients with NaCoA, BAP was successful in 71%, with median PPG decreasing from 32 mmHg (IQR 25-46) to 17 mmHg (IQR 4-23) (p = .02), and ESI was successful in 100%, with median PPG decreasing from 20 mmHg (IQR 14.5-40) to 2 mmHg (IQR 0-6) (p < .01). In patients with ReCoA, BAP was successful in 69%, with median PPG decreasing from 20 mmHg (IQR 16-31.3) to 9 mmHg (IQR 0-14.3) (p < .001), and ESI was successful in 100%, with median PPG decreasing from 18 mmHg (IQR 11.5-22.8) to 0 mmHg (IQR 0-3.5) (p < .01). ESI was more successful than BAP (p = .01). There was only one complication. CONCLUSIONS: Percutaneous management of CoA is safe and effective in both NaCoA and ReCoA. Stent implantation is more effective than BAP.

Indole-3-carbinol, a plant nutrient and AhR-Ligand precursor, supports oral tolerance against OVA and improves peanut allergy symptoms in mice.

In general, dietary antigens are tolerated by the gut associated immune system. Impairment of this so-called oral tolerance is a serious health risk. We have previously shown that activation of the ligand-dependent transcription factor aryl hydrocarbon receptor (AhR) by the environmental pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) affects both oral tolerance and food allergy. In this study, we determine whether a common plant-derived, dietary AhR-ligand modulates oral tolerance as well. We therefore fed mice with indole-3-carbinole (I3C), an AhR ligand that is abundant in cruciferous plants. We show that several I3C metabolites were detectable in the serum after feeding, including the high-affinity ligand 3,3´-diindolylmethane (DIM). I3C feeding robustly induced the AhR-target gene CYP4501A1 in the intestine; I3C feeding also induced the aldh1 gene, whose product catalyzes the formation of retinoic acid (RA), an inducer of regulatory T cells. We then measured parameters indicating oral tolerance and severity of peanut-induced food allergy. In contrast to the tolerance-breaking effect of TCDD, feeding mice with chow containing 2 g/kg I3C lowered the serum anti-ovalbumin IgG1 response in an experimental oral tolerance protocol. Moreover, I3C feeding attenuated symptoms of peanut allergy. In conclusion, the dietary compound I3C can positively influence a vital immune function of the gut.

Fingolimod promotes peripheral nerve regeneration via modulation of lysophospholipid signaling.

BACKGROUND: The lysophospholipids sphingosine-1-phosphate (S1P) and lysophosphatidic acid (LPA) are pleiotropic signaling molecules with a broad range of physiological functions. Targeting the S1P1 receptor on lymphocytes with the immunomodulatory drug fingolimod has proven effective in the treatment of multiple sclerosis. An emerging body of experimental evidence points to additional direct effects on cells of the central and peripheral nervous system. Furthermore, fingolimod has been reported to reduce LPA synthesis via inhibition of the lysophospholipase autotaxin. Here we investigated whether modulation of particular signaling aspects of S1P as well as LPA by fingolimod might propagate peripheral nerve regeneration in vivo and independent of its anti-inflammatory potency. METHODS: Sciatic nerve crush was performed in wildtype C57BL/6, in immunodeficient Rag1 (-/-) and Foxn1 (-/-) mice. Analyses were based on walking track analysis and electrophysiology, histology, and cAMP formation. Quantification of different LPA species was performed by liquid chromatography coupled to tandem mass spectrometry. Furthermore, functional consequences of autotaxin inhibition by the specific inhibitor PF-8380 and the impact of fingolimod on early cytokine release in the injured sciatic nerve were investigated. RESULTS: Clinical and electrophysiological measures indicated an improvement of nerve regeneration under fingolimod treatment that is partly independent of its anti-inflammatory properties. Fingolimod treatment correlated with a significant elevation of axonal cAMP, a crucial factor for axonal outgrowth. Additionally, fingolimod significantly reduced LPA levels in the injured nerve. PF-8380 treatment correlated with improved myelin thickness. Sciatic nerve cytokine levels were not found to be significantly altered by fingolimod treatment. CONCLUSIONS: Our findings provide in vivo evidence for direct effects of fingolimod on cells of the peripheral nervous system that may propagate nerve regeneration via a dual mode of action, differentially affecting axonal outgrowth and myelination by modulating relevant aspects of S1P and LPA signaling.

A sensitive method for the determination of hordenine in human serum by ESI⁺ UPLC-MS/MS for forensic toxicological applications.

We present the determination of the alkaloid hordenine and its forensic relevance as a qualitative and quantitative marker for beer consumption. A simple, rapid and sensitive ultra-performance liquid chromatography (UPLC)-tandem mass spectrometry (MS/MS) method for the determination of hordenine in human serum samples was developed and validated. The application was tested with serum samples after enzymatic cleavage. After addition of the synthesized internal standard hordenine-D 4, a liquid-liquid extraction with dichloromethane and diethyl ether was performed. Chromatographic separation was conducted with a Waters Acquity® UPLC system with gradient elution on an Agilent Eclipse XDB-C18 column (4.6 mm × 150 mm, 5-µm particle size). For quantification, a Waters Acquity® TQ detector (version SNC 627) with a positive electrospray ionization probe and multiple reaction monitoring mode was used. A flow rate of 0.4 ml/min was applied. The retention time for both the analyte and the internal standard was 3.67 min. Linearity was demonstrated from 0.2 to 16 ng/ml (R(2) > 0.999). The lower limit of quantification was 0.3 ng/ml in serum. Matrix effects and extraction recoveries for low and high concentrations were within acceptable limits of 75-125% and 50%, respectively. To the best of our knowledge there is no corresponding method for the determination of hordenine by UPLC-MS/MS in serum. By our drinking studies we demonstrate that beer consumption leads to detectable hordenine concentrations in serum and observed a linear elimination of total hordenine correlating to blood alcohol concentration, which shows that hordenine can be used as a reliable qualitative and quantitative marker for beer consumption. The validated method was successfully applied to serum from actual forensic cases.