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.
Adolescent ; Asthma ; Bronchial Provocation Tests ; Child ; Humans ; Leukotriene D4 ; Methacholine Chloride ; Respiratory Hypersensitivity

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.
Diagnosis ; Estrogens, Conjugated (USP) ; Histamine ; Humans ; Leukotriene D4 ; Pruritus ; Quality of Life ; Rhinitis, Allergic ; Sneezing

OBJECTIVETo investigate the effects of cysteinyl leukotriene (CysLT) receptor agonist leukotriene D4 (LTD4) on proliferation and migration in lung epithelial A549 cells.

METHODSThe expression of CysLT1 receptor and CysLT2 receptor was determined by immunofluoresence staining in A549 cells. A549 cells were treated with LTD4 (0.01-100 nmol/L) for 24-72 h. Cell viability was detected by MTT reduction assay. Cell migration was determined by modified scratch and healing model.

RESULTSIn A549 cells, CysLT1 receptor and CysLT2 receptor were mainly expressed in the cytoplasm, membrane and few in the nuclei. The treatment of LTD4 (0.01-100 nmol/L) for 24-72 h caused no effect on cell viability (Ps>0.05); when A549 cells were treated with 100 nmol/L LTD4 for 24, 48 and 72 h the cell viability was (103.00±4.46)%，(107.00±9.45)% and (105.00±9.02)% of control, respectively (Ps>0.05). The migration rate of A549 cells after scratching during the first 24 h was markedly greater than that during the second and third 24 h in the same concentration groups; however, no significant difference in migration rate was noticed when the cells were treated with different concentrations of LTD4 (0.01-100 nmol/L)(Ps>0.05). The migration of A549 cells was 1.15-fold, 1.21-fold and 1.06-fold of that of control when the cells were treated with 100 nmol/L LTD4 for 24, 48 and 72 h, respectively (Ps>0.05).

CONCLUSIONThe proliferation and migration of A549 cells are not changed when treated with 0.01-100 nmol LTD4 for up to 72h.

Cell Line ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Epithelial Cells ; cytology ; drug effects ; Humans ; Leukotriene D4 ; pharmacology ; Pulmonary Alveoli ; cytology

OBJECTIVETo investigate the effects of CysLT receptor agonist leukotriene D4(LTD4) and antagonists on activation of microglia BV2 cells.

METHODSThe expression of CysLT1 and CysLT2 protein was determined by Western blotting and immunostaining in microglia BV2 cells. BV2 cells were pretreated with or without CysLT1 receptor selective antagonist montelukast, CysLT2 receptor selective antagonist HAMI 3379, or CysLT1/CysLT2 receptor dual antagonist BAY u9773 for 30 min, then the cells were treated with LTD4 for 24 h. Cell viability was detected by MTT reduction assay. Phagocytosis and mRNA expression of IL-6 were determined by fluorescent bead tracking and RT-PCR, respectively.

RESULTSIn BV2 cells, LTD4 did not affect proliferation but significantly enhanced phagocytosis and increased IL-6 mRNA expression in a concentration-dependent manner. LTD4 at 100 nmol/L induced a 1.4-fold increase of phagocytic index and a 2-fold up-regulation of IL-6 mRNA expression (P<0.01). HAMI 3379 and BAY u9773 (100 nmol/L) further increased LTD4-induced phagocytosis; BAY u9773 and montelukast decreased LTD4-induced IL-6 mRNA expression, while HAMI 3379 had no effect on that.

CONCLUSIONLTD4 activates BV2 cells in vitro and enhances IL-6 mRNA expression mediated by CysLT1 receptor, LTD4 induces phagocytosis which might be negatively regulated by CysLT2 receptor in BV2 cells.

Acetates ; pharmacology ; Cell Line ; Cell Proliferation ; Cyclohexanecarboxylic Acids ; pharmacology ; Humans ; Interleukin-6 ; metabolism ; Leukotriene Antagonists ; pharmacology ; Leukotriene D4 ; pharmacology ; Microglia ; cytology ; metabolism ; Phagocytosis ; Phthalic Acids ; pharmacology ; Quinolines ; pharmacology ; Receptors, Leukotriene ; metabolism ; SRS-A ; analogs & derivatives ; pharmacology

OBJECTIVETo investigate the role of cysteinyl leukotriene (CysLT) receptors in the differentiation of rat glioma C6 cells.

METHODSRat glioma C6 cells were treated with the agonist LTD(4), the CysLT(1) receptor antagonist montelukast and the differentiation inducer forskolin. Cell morphology and GFAP protein expression were determined after treatments.

RESULTForskolin (10 μmol/L) induced morphological changes and GFAP protein expression (cell differentiation) in C6 cells, but LTD(4) (0.1-100 nmol/L) did not induce these changes. Montelukast (1 μmol/L) alone did not affect C6 cell differentiation, while it induced the differentiation when combined with the LTD(4) (100 nmol/L).

CONCLUSIONThe CysLT(2) receptor may modulate the differentiation of rat glioma C6 cells.

Acetates ; pharmacology ; Animals ; Cell Differentiation ; drug effects ; Cell Line, Tumor ; Colforsin ; pharmacology ; Cysteine ; Glioma ; metabolism ; pathology ; Leukotriene Antagonists ; pharmacology ; Leukotriene D4 ; pharmacology ; Leukotrienes ; Quinolines ; pharmacology ; Rats ; Receptors, Leukotriene ; agonists

OBJECTIVE: To investigate the changes of leukotriene D4 (LTD4) in nasal discharge and plasma of patients with persistent allergic rhinitis (AR) and the effects of antihistamine. METHOD: The investigation was a prospective, randomized controlled trial. Forty AR patients (group C) were divided randomly into two subgroup. One group received oral antihistamine 10 mg everyday for one week (group CA) and another group received no loratadine tablets 10 mg everyday for one week (group CB). Fifteen age matched healthy (group D) people were enrolled as control. The level of LTD4 and interleukin-5 (IL-5) in both nasal discharge and plasma by using enzyme linked immunosorbent assay (ELISA) and enzyme immunoassay (EIA), cell counts and cell differentials in nasal discharge, were measured before and after three month. The clinical symptom and life quality scores of group C were also investigated. RESULT: The concentrations of LTD4 in nasal discharge [(794 +/- 305) pg] and plasma [(5219 +/- those in group D [(347 +/- 169) pg, (2283 +/- 489) ng/L, all P 1185) ng/L] in group C were significantly higher than those in group D [(347 +/- 169) pg, (2283 +/- 489) ng/L, all P < 0.05]. The level of LTD4 in nasal discharge was positively correlated with the percentage of neutrophil (r = 0.453, P < 0.05) and IL-5 (r = 0.364, P < 0.05). The pre- and post-therapy concentrations of nasal discharge and plasma in group CA were (812 +/- 1592) pg, (657 +/- 495) pg and (5422 +/- 935) ng/L, (4589 +/- 1057) ng/L respectively; While in group CB the concentrations were (776 +/- 227) pg, (860 +/- 194) pg and (5074 +/- 1850) ng/L, (6063 +/- 450) ng/L, respectively. There were no significant difference either in the level of LTD4 in nasal discharge or in plasma in both groups (all P > 0.05). CONCLUSION The results suggested that LTD4 was involved in airway inflammation in AR. Antihistamine was not effective enough in decreasing the levels of LTD4 in both nasal discharge and plasma of AR patients.
Adult ; Anti-Allergic Agents ; pharmacology ; Bodily Secretions ; chemistry ; Female ; Histamine H1 Antagonists ; pharmacology ; Humans ; Leukotriene Antagonists ; therapeutic use ; Leukotriene D4 ; analysis ; blood ; metabolism ; Male ; Middle Aged ; Plasma ; chemistry ; Prospective Studies ; Rhinitis, Allergic, Perennial ; blood ; drug therapy ; metabolism

Bronchiolitis ; diagnosis ; microbiology ; pathology ; Female ; Humans ; Infant ; Leukotriene D4 ; analysis ; Male ; Nasopharynx ; chemistry ; microbiology ; pathology

OBJECTIVETo establish a method for screening cysteinyl leukotriene receptor 2 (CysLT(2)) antagonists and to preliminarily screen a series of synthetic compounds.

METHODSRat glioma cell line (C6 cells) highly expressing CysLT(2) receptor was used. Intracellular calcium concentration was measured after stimulation with the agonist LTD(4),which was used to screen compounds with antagonist activity for CysLT(2) receptor. Bay u9773, a CysLT1/CysLT(2) receptor non-selective antagonist, and AP-100984, a CysLT(2) receptor antagonist, were used as control.

RESULTPT-PCR showed a higher expression of CysLT(2) receptor in C6 cells. LTD(4) at 1 mumol/L significantly increased intracellular calcium in C6 cells; the maximal effect was about 37.5% of ATP, a positive stimulus.LTD(4)-induced increase of intracellular calcium was blocked by CysLT(2) receptor antagonists, but not by CysLT(1) receptor antagonists. Among the synthetic compounds, D(XW-)1,2,13,23,29 and 30 inhibited LTD(4)-induced increase of intracellular calcium.

CONCLUSIONLTD(4)-induced change in intracellular calcium in C6 cells can be used as a screening method for CysLT(2) receptor antagonists. The compounds, D(XW-)1,2,13,23,29 and 30, possess antagonist activity for CysLT(2) receptor.

Animals ; Brain Neoplasms ; pathology ; Cell Line, Tumor ; Drug Evaluation, Preclinical ; methods ; Glioma ; pathology ; Leukotriene Antagonists ; isolation & purification ; Leukotriene D4 ; metabolism ; pharmacology ; Rats ; Receptors, Leukotriene ; chemistry

OBJECTIVETo determine whether cysteinyl leukotriene receptor agonist LTD(4) and cysteinyl leukotriene receptor 1 (CysLT(1)) antagonist pranlukast affect the differentiation of human neuroblastoma SK-N-SH cells.

METHODSSK-N-SH cell morphological changes induced by LTD(4), pranlukast and LTD(4) + pranlukast were observed with retinoid acid (RA) as the positive control. The expressions of CysLT(1) and CysLT(2) receptors were detected by immunoblotting analysis, and the expression of microtubule-associated protein-2 (MAP-2), a neuron marker, was detected by fluorescent immunostaining.

RESULTThe immunoblotting results showed that SK-N-SH cells expressed CysLT(1) receptor moderately, and CysLT(2) receptor highly. The morphological results showed that RA, pranlukast and LTD(4) + pranlukast induced the compaction of the cell bodies and the outgrowth of neurites, while LTD(4) had no significant effect. The immunostaining results showed that MAP-2 was distributed in the cell bodies in control or pranlukast-treated cells; it was distributed in cell bodies and neuritis in RA-treated cells. Pranlukast increased the numbers of MAP-2-positive cells.

CONCLUSIONThe CysLT(1)receptor antagonist pranlukast modulates the differentiation of SK-N-SH cells.

Cell Differentiation ; drug effects ; Cell Line, Tumor ; Chromones ; pharmacology ; Humans ; Immunoblotting ; Immunohistochemistry ; Leukotriene Antagonists ; pharmacology ; Leukotriene D4 ; pharmacology ; Membrane Proteins ; metabolism ; Microtubule-Associated Proteins ; metabolism ; Neuroblastoma ; metabolism ; pathology ; Receptors, Leukotriene ; metabolism

OBJECTIVETo determine the effect of cysteinyl receptor agonist leukotriene D(4) (LTD(4)) and its antagonists on rat primary neurons.

METHODSIn the primarily cultured rat cortical neurons, the neuron injury was evaluated by measuring intracellular calcium, 3-(4, 5-dimethylthiazol-2yl)-2, 5-diphenyl tetrazolium bromide (MTT) reduction, and propidium iodide (PI) and Hoechst 33258 staining. The in vitro ischemic injury was induced by oxygen-glucose deprivation (OGD) for 1.5 h and reperfusion for 24 h.

RESULTLTD(4) (0.01-1 micromol/L) did not induce the elevation of intracellular calcium, neuron viability changes and neuron death. OGD-induced injury was not significantly ameliorated by the CysLT(1) receptor antagonists, pranlukast (0.2-10 micromol/L) and montelukast (0.2-10 micromol/L), as well as by the CysLT(1)/CysLT(2) receptor non-selective antagonist, BAY u9773 (0.02-1 micromol/L).

CONCLUSIONNeither agonist nor antagonists of cysteinyl receptors have the effects on the viability and ischemic-like injury in rat primary neurons.

Acetates ; pharmacology ; Animals ; Animals, Newborn ; Calcium ; metabolism ; Cell Hypoxia ; Cell Survival ; drug effects ; Cells, Cultured ; Cerebral Cortex ; cytology ; Chromones ; pharmacology ; Glucose ; pharmacology ; Leukotriene Antagonists ; pharmacology ; Leukotriene D4 ; pharmacology ; Neurons ; cytology ; drug effects ; metabolism ; Quinolines ; pharmacology ; Rats ; Receptors, Leukotriene ; agonists