Leukotriene D4 bronchial provocation test for detection of airway hyper-responsiveness in children / 南方医科大学学报

OBJECTIVE@#To explore the value of leukotriene D4 (LTD4) bronchial provocation test (BPT) in detection of airway hyper-responsiveness (AHR) in children.@*METHODS@#A total of 151 children aged 6 to 14 years, including 86 in remission of asthma and 65 with acute bronchitis, who were followed up in our respiratory clinic between November, 2017 and August, 2018. The children were randomly divided into LTD4 group (78 cases) and methacholine (MCH) group (73 cases). In LTD4 group, the 78 children underwent LTD4-BPT, including 46 with asthma and 32 children having re-examination for previous episodes of acute bronchitis; in MCH group, the 73 children underwent MCH-BPT, including 40 with asthma and 33 with acute bronchitis. MCH-BPT was also performed in the asthmatic children in the LTD4 group who had negative responses to LTD4 after an elution period. The major adverse reactions of the children to the two BPT were recorded. The diagnostic values of the two BPT were evaluated using receiver-operating characteristic (ROC) curve.@*RESULTS@#There was no significant difference in the results of basic lung function tests between LTD4 group and MCH group (>0.05). The positive rate of BPT in asthmatic children in the LTD4 group was significantly lower than that in the MCH group (26.1% 72.5%; < 0.05). The positive rate of BPT in children with previous acute bronchitis in the LTD4 group was lower than that in the MCH group (3.1% 15.2%). The positive rate of MCH-BPT in asthmatic children had negative BPT results in LTD4 group was 58.8%, and their asthma was mostly mild. The sensitivity was lower in LTD4 group than in MCH group (0.2609 0.725), but the specificity was slightly higher in LTD4 group (0.9688 vs 0.8485).The area under ROC curvein LTD4 group was lower than that in MCH group (0.635 0.787). In children with asthma in the LTD4 group, the main adverse reactions in BPT included cough (34.8%), shortness of breath (19.6%), chest tightness (15.2%), and wheezing (10.9%). The incidence of these adverse reactions was significantly lower in LTD4 group than in MCH group ( < 0.05). Serious adverse reactions occurred in neither of the two groups.@*CONCLUSIONS@#LTD4-BPT had high safety in clinical application of children and was similar to the specificity of MCH-BPT. However, it had low sensitivity, low diagnostic value, and limited application value in children's AHR detection.

Correlations of nasal responses to leukotriene D4 and histamine nasal provocation with quality of life in allergic rhinitis

BACKGROUND: The symptoms of allergic rhinitis (AR) greatly affect the quality of life (QoL) in the patients with AR. The correlations of nasal response to leukotriene D4 (LTD4) and histamine nasal provocation with health related QoL in AR are not clear. OBJECTIVE: To evaluate the correlations of nasal response to LTD4 and histamine nasal challenge with QoL in AR. METHODS: Patients randomly underwent LTD4 and histamine nasal challenge tests, completed the rhinoconjunctivitis quality of life questionnaire (RQoLQ), and rating the symptom severity score (total symptom score 4, TSS4) in the previous week. The correlations between nasal challenge tests induced nasal responses and QoL in RQoLQ were analyzed. RESULTS: A total of 25 eligible AR patients enrolled and finished both LTD4 and histamine nasal challenge and completed the questionnaire of RQoLQ. Histamine nasal challenge induced sneezing, increased nasal resistant were correlated with most of the dimensions (general, practical, nasal, eye problems, and quality of sleep, p < 0.05), while LTD4 nasal challenge induced sneeze, increased nasal resistant only correlated with nasal and ocular problems. On the contrary, the severity of the sneeze assessed by TSS4, was not correlated with QoL, while the severity of rhinorrhea, congestion, and nasal pruritus were correlated with nasal and practical problems, and nasal congestion was also correlated with ocular problems (r = 0.60, p = 0.01). CONCLUSION: LTD4 and histamine nasal challenge induced nasal responses were correlated with different clinical symptoms severity and QoL, which can be used as a good diagnosis and evaluation methods for the management of AR.

Expression and function of cysteinyl leukotriene receptors on human keratinocytes / 中华皮肤科杂志

Objective To detect the expression and function of cysteinyl leukotriene receptors (CysLTRs)in keratinocytes.Methods Human keratinocytes were isolated from the tissue of foreskin by digestion with dispase Ⅱ and trypsin,and subjected to primary culture.By using confocal laser scanning microscopy and reverse transcriptase PCR,the localization and expression of CysLTRs were studied in kemtinocytes.respectively.Some primarily cultured keratinocytes were pretreated with leukotriene D4 (30 nmoi/L),MK571(300 nmol/L),and BAYu9773 for 5 minutes followed by the detection of intmcellular calcium level using the Ca2+ indicator dye Fura-2/AM as well as cell proliferation bv MTT assay.Results The expressions of CysLTR1 and CysLTR2 were observed in cultured keratinocytes,and they were mainly located on cell membrane,partly in cytoplasm and nuclei.Compared with non.stimulated cells,a significant increase Was noted in the expression of CysLTRs,especially in the nuclei of keratinocytes stimulated by LTD4(P＜0.05),together with an elevation in intracellular calcium level(42.27±3.00 mmol/L,P＜0.01)and acceleration in cell proliferation (P＜0.01).However,both MK571 and BAYu9773 could completely block the effect of LTD4 on intmcellular calcium level and cell proliferation.and there was no significant difference in the blocking effect between MK571 and BAYu9773.Conclusions Functional CysLTRs are expressed in human keratinocytes.and they carl increase the intracellular calcium level in,and cell proliferation of,keratinocytes.

MUC2/5AC Expression and Mucin Secretion through Leukotriene Receptor in Human Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Mucin gene expression and mucin production are highly increased during inflammatory airway disorders such as, asthma, chronic bronchitis and sinusitis. Cytokines, lipopolysaccharides and other inflammatory mediators are related with secretion and production of mucin. However, among of inflammatory mediators, the relation of leukotrienes and mucin genes expression is not clear. The aim of this study is to evaluate MUC2/5AC genes expression and mucin secretion through leukotriene receptor in human airway epithelial cells. SUBJECTS AND METHOD: The effect of Leukotriene D4 and leukotriene receptor antagonist, pranlukast hydrate (ONO-1078) on the regulation of MUC2/5AC gene expression and mucin secretion was observed in the human airway NCI-H292 epithelial cells. The mRNA levels of MUC2/5AC and the amount of mucin protein were determined by reverse transcription-polymerase chain reaction (RT-PCR) and immunoassay. RESULTS: Leukotriene D4 upregulated MUC2/5AC gene expression and mucin secretion on a dose dependent pattern. Pranlukast hydrate (ONO-1078, 100 micrometer) downregulated the leukotriene D4-mediated MUC2/5AC gene expression and mucin secretion. CONCLUSION: These results suggest that the leukotriene receptor system is one of the expression mechanisms of MUC2/5AC genes and mucin secretion.

Effects of polysaccharides from cryptoporus volvatus(peck) schear on leukotrienes generation in guinea pig lung / 中国药理学通报

AIM: To study the effects of polysaccharides of ferment cultured cryptoporus volvatus (CVPS) on release of leukotrienes from guinea pig lung and Schultz - Dale reaction. METHODS: The bioassay method and reversed phase high-performance liquid chromatography (RP-HPLC) were used to analyze SRS-A or LTD4 from sensitized or normal guinea pig, after challenged with antigen or A23187 respectively. The antiallergic effects of CVPS were evaluated with Schultz-Dale reaction. RESULTS: The release of SRS-A or LTD4 from sensitized or normal guinea pigs were greatly reduced by CVPS after antigen or A23187 challenge. The CVPS could also inhibit the Schultz-Dale reaction of sensitized guinea pig (IC50 = 0.49 g·L-1). CONCLUSION: The effects of CVPS involved in inhibiting release of leukotrienes from lung and antiallergy.

The inhibitory effect of eupatilin on Helicobacter pylori-induced release of leukotriene D4 in the human neutrophils and gastric mucosal cells

In this report, the inhibitory action of eupatilin was investigated by using leukotriene D4 in the human neutrophils and Kato III cells (Gastric adenoma cells as a substitute for gastric mucosal cells) stimulated by Helicobacter pylori. Leukotriene D4 (LTD4) was released from both neutrophils and Kato III cells when these cells were incubated with H. pylori. The release of LTD4 increased time-dependently and the maximum release of LTD4 was 2.3-2.5 pmol. But in the presence of eupatilin, the release of LTD4 from these cells was inhibited in a dose-dependent manner. In the neutrophils, die release of LTD4 was suppressed to 70% and 50% of the control levels when neutrophils was incubated with 0.01 and 0.1 mM of eupatilin. In the Kato III cells, the release of LTD4 was suppressed to 59% and 27% of the control levels by adding 0.01 and 0.1 mM of eupatilin. We estimated the intracellular Ca2+ levels when Kato III cells and neutrophils were stimulated by H. pylori using 45Ca. But the suppressive effect of eupatilin on Ca2+ influx into these cells was not significant. We also obtained the results that H. pylori induced Ca2+ influx into these cells by confocal microscopy, however there was no differences in the dose level of eupatilin. These results were confirmed by 1H Nuclear Magnetic Resonance(NMR) spectroscopy. The NMR patterns of eupatilin in the absence of Ca2+ was changed compare with when Ca2+ was present, but its effect was not strong.

Effects of Leukotriene D4 on Ultrastructure of Nasal Mucous Membrane in Guinea Pigs / 대한이비인후과학회지

The aim of this study was to evaluate effects of leukotriene D4(LTD4) on the nasal airway. Fifteen guinea pigs were divided into two groups;10 for experimental group and 5 for control group. Two l of 10(-5)mol LTD4 was administered to both nasal cavities in experimental group and same volume of normal saline in control group. Transmission electron microscopy was performed to investigate ultrastructural change of the nasal mucosal membrane in LTD4 administered guinea pigs. Infiltration of neutrophils and eosinophils from the capillaries were seen in the perivascular space. In the capillaries, some endothelial cells degenerated and intercellular spaces of the cells were widened, especially 6 hours later. Degranulated mast cells and neutrophils were found in the lumen of the capillaries. Several red blood cells with low electron density were seen in the shrunken vessels. The giant mitochondriae with inclusion bodies were observed. The results of this study suggest that leukotriene may be a potent mediator to induce biphasic response in the nasal passage of guinea pigs.