montelukast and Disease-Models--Animal

Preclinical pharmacological studies have demonstrated that cysLT, receptor antagonists, such as zafirlukast, montelukast, and pobilukast, are potent and selective antagonists of cysteinyl leukotriene (cysLT) activity. In vitro, these agents compete with [3H]LTD4 for binding to cysLT, receptors present on guinea pig and human lung cell membranes. Both zafirlukast and montelukast have affinities that are approximately two times greater than that of the natural ligand, LTD4. These agents block LTD4- and LTE4-induced contractions of isolated guinea pig trachea, but do not antagonize LTC4-induced contractions, which are putatively mediated by a different LT receptor, cysLT2. The cysLT2 receptor, however, has not yet been found in human airway smooth muscle. In animal models, these drugs inhibit LTD4-, LTE4-, and antigen-induced bronchoconstriction, reduce inflammatory markers in models of pulmonary inflammation, and inhibit antigen-induced late-phase bronchoconstriction. This preclinical profile suggests that cysLT, receptor antagonists may be useful in treating inflammatory conditions of the respiratory system, such as asthma and allergic rhinitis.

Topics: Acetates; Animals; Anti-Asthmatic Agents; Asthma; Bronchoconstriction; Cyclopropanes; Dicarboxylic Acids; Disease Models, Animal; Humans; In Vitro Techniques; Indoles; Leukotriene Antagonists; Phenylcarbamates; Quinolines; Sulfides; Sulfonamides; Tosyl Compounds

Allergic rhinitis as common airway disease has high prevalence in all peoples worldwide. In allergic diseases, Th2 cells release type 2 cytokines that support the inflammation in airways. All the drugs used for allergic rhinitis do not cure completely, and the choice of drugs according to cost and efficacy is very important in all groups of atopic patients. Therefore, in this study, the effect of commercial drugs on cytokine gene expression has been studied. Male Balb/c mice were divided into six groups. Allergic rhinitis was induced in five of the six groups with ovalbumin, and four of these five groups were treated with salbutamol, budesonide, theophylline, and montelukast. The fifth group was used as positive control group and the sixth group as negative control group. For the survey, RNA was extracted, cDNA was synthesized, and quantitative real-time PCR was done for 21 genes. The four drugs had different effects on mRNA expression of cytokines (IL-1b, 2, 4, 5, 7, 8, 9, 11, 12, 13, 17, 18, 22, 25, 31, 33, 37, IFN-γ, TNF-α, TGF-β1, and eotaxin) in the allergic rhinitis groups. Salbutamol can be used during pregnancy and breastfeeding, but it has some side effects. Budesonide in the inhaled form is generally safe in pregnancy. Theophylline cannot control allergic attack in the long run. Montelukast is not useful in the treatment of acute allergic attacks. Immunomodulatory and anti-inflammatory effects of drugs in control of allergic rhinitis via Th2 cytokines can be new approaches in molecular medicine.

Topics: Albuterol; Animals; Budesonide; Cytokines; Disease Models, Animal; Gene Expression; Male; Mice; Mice, Inbred BALB C; Ovalbumin; Rhinitis, Allergic; Theophylline

The main pathological characteristics of demyelinating diseases are central nervous system (CNS) myelin damage, and the differentiation of oligodendrocyte precursor cells is the therapeutic target of myelin repair. Previous studies have found that a large number of platelet-derived growth factor receptor α(PDGFRα) positive oligodendrocyte progenitor cells (OPCs) accumulate in the lesion area of myelin injury, and differentiation is blocked. However, the therapeutic effects of drugs currently used clinically on OPCs differentiation and myelin repair are limited. The main reason is that it is difficult to reach the effective concentration of the drug in the lesion area. Therefore, efficiently delivering into the CNS lesion area is of great significance for the treatment of MS. Natural exosomes have good biocompatibility and are ideal drug carriers. The delivery of drugs to lesion areas can be achieved by giving the exosomes armed targeting ligand. Therefore, in this study, combining exosomes with PDGFA helps them accumulate in OPCs in vitro and in vivo. Further, load montelukast into exosomes to achieve targeted therapy for cuprizone-induced demyelination animal model. The implementation of this research will help provide effective treatments for demyelinating diseases and lay a theoretical foundation for its application in the clinical treatment of different demyelinating diseases.

Topics: Acetates; Animals; Cell Differentiation; Cell Lineage; Cuprizone; Cyclopropanes; Demyelinating Diseases; Disease Models, Animal; Drug Delivery Systems; Exosomes; Extracellular Vesicles; In Vitro Techniques; Ligands; Male; Mice; Mice, Inbred C57BL; Myelin Basic Protein; Myelin Sheath; Neurons; Oligodendrocyte Precursor Cells; Oligodendroglia; Phagocytosis; Quinolines; Receptor, Platelet-Derived Growth Factor alpha; Regeneration; Stem Cells; Sulfides

One of the most complex clinical challenges facing medical practice is sepsis-induced lung dysfunction resulting from polymicrobial sepsis. Although many therapeutic approaches have been used in such clinical challenges, there is still further need for a new effective therapeutic approach. The objective of this study was to investigate if Montelukast could protect the lungs during polymicrobial sepsis by regulating inflammatory markers and the oxidative stress pathways. Twenty-four mature male Swiss-albino mice aged 8-12 weeks, with a weight of 20-30 g, were randomized into 4 equal groups (n=6), sham (laparotomy without cecal ligation and puncture (CLP)), CLP (laparotomy with CLP), vehicle 1 (equivalent volume of DMSO 1 hour prior to CLP), Montelukast (10 mg/kg IP 1 hour prior to CLP). Lung tissue pro-inflammatory mediators IL-6, IL-1β, IL-17, LTB-4 12(S) HETE, and oxidative stress were assessed using ELISA. The levels of F2 isoprostane were considerably greater in the sepsis group (p<0.05) as compared to the sham group, while Montelukast was significantly lower (p<0.05) in these inflammatory mediators and oxidative stress as compared to the sepsis group. Histologically, the lung tissue damage was significant (p<0.05) in all mice in the sepsis group, while Montelukast significantly reduced lung tissue injury (p<0.05). The current findings indicated that Montelukast could attenuate lung dysfunction during CLP-induced polymicrobial sepsis in male mice through their modulating effects on pro-inflammatory and oxidative stress downstream signalling pathways and subsequently decrease lung tissue cytokine concentrations (IL-1β, IL-6, IL-17, LTB-4, and 12(S)HETE).

Topics: Acetates; Animals; Anti-Inflammatory Agents; Antioxidants; Cyclopropanes; Disease Models, Animal; Hydroxyeicosatetraenoic Acids; Inflammation Mediators; Interleukin-17; Interleukin-6; Lung; Male; Mice; Quinolines; Sepsis; Sulfides

Encephalopathy of prematurity (EoP) affects approximately 30% of infants born < 32 weeks gestation and is highly associated with inflammation in the foetus. Here we evaluated the efficacy of montelukast, a cysteinyl leukotriene receptor antagonist widely used to treat asthma in children, to ameliorate peripheral and central inflammation, and subsequent grey matter neuropathology and behaviour deficits in a mouse model of EoP. Male CD-1 mice were treated with intraperitoneal (i.p.) saline or interleukin-1beta (IL-1β, 40 μg/kg, 5 μL/g body weight) from postnatal day (P)1-5 ± concomitant montelukast (1-30 mg/kg). Saline or montelukast treatment was continued for a further 5 days post-injury. Assessment of systemic and central inflammation and short-term neuropathology was performed from 4 h following treatment through to P10. Behavioural testing, MRI and neuropathological assessments were made on a second cohort of animals from P36 to 54. Montelukast was found to attenuate both peripheral and central inflammation, reducing the expression of pro-inflammatory molecules (IL-1β, IL-6, TNF) in the brain. Inflammation induced a reduction in parvalbumin-positive interneuron density in the cortex, which was normalised with high-dose montelukast. The lowest effective dose, 3 mg/kg, was able to improve anxiety and spatial learning deficits in this model of inflammatory injury, and alterations in cortical mean diffusivity were not present in animals that received this dose of montelukast. Repurposed montelukast administered early after preterm birth may, therefore, improve grey matter development and outcome in EoP.

Topics: Acetates; Animals; Brain Diseases; Disease Models, Animal; Female; Gray Matter; Humans; Infant, Newborn; Inflammation; Male; Mice; Premature Birth; Quinolines

Glaucoma is the second leading cause of blindness worldwide. This multifactorial, neurodegenerative group of diseases is characterized by the progressive loss of retinal ganglion cells (RGCs) and their axons, leading to irreversible visual impairment and blindness. There is a huge unmet and urging need for the development of new and translatable strategies and treatment options to prevent this progressive loss of RGC. Accumulating evidence points towards a critical role of neuroinflammation, in particular microglial cells, in the pathogenesis of glaucoma. Leukotrienes are mediators of neuroinflammation and are involved in many neurodegenerative diseases. Therefore, we tested the leukotriene receptors CysLT1R/GPR17-selective antagonist Montelukast (MTK) for its efficacy to modulate the reactive state of microglia in order to ameliorate RGCs loss in experimental glaucoma. Ocular hypertension (OHT) was induced unilaterally by injection of 8 μm magnetic microbead (MB) into the anterior chamber of female Brown Norway rats. The contralateral, untreated eye served as control. Successful induction of OHT was verified by daily IOP measurement using a TonoLab rebound tonometer. Simultaneously to OHT induction, one group received daily MTK treatment and the control group vehicle solution by oral gavage. Animals were sacrificed 13-15 days after MB injection. Retina and optic nerves (ON) of OHT and contralateral eyes were analyzed by immunofluorescence with specific markers for RGCs (Brn3a), microglial cells/macrophages (Iba1 and CD68), and cysteinyl leukotriene pathway receptors (CysLT1R and GPR17). Protein labeling was documented by confocal microscopy and analyzed with ImageJ plugins. Further, mRNA expression of genes of the inflammatory and leukotriene pathway was analyzed in retinal tissue. MTK treatment resulted in a short-term IOP reduction at day 2, which dissipated by day 5 of OHT induction in MTK treated animals. Furthermore, MTK treatment resulted in a decreased activation of Iba1

Topics: Acetates; Animals; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Biomarkers; Calcium-Binding Proteins; Cell Survival; Cyclopropanes; Disease Models, Animal; Electroretinography; Female; Gene Expression Regulation; Intraocular Pressure; Leukotriene Antagonists; Microfilament Proteins; Microglia; Microscopy, Confocal; Microscopy, Fluorescence; Ocular Hypertension; Quinolines; Rats; Rats, Inbred BN; Real-Time Polymerase Chain Reaction; Receptors, G-Protein-Coupled; Receptors, Leukotriene; Retina; Retinal Ganglion Cells; RNA, Messenger; Sulfides; Tonometry, Ocular; Transcription Factor Brn-3B

The leukotrienes are inflammatory mediators. In the present study, the analgesic role of local montelukast, a cysteinyl leukotriene receptor antagonist, and the possible involvement of L-arginine/NO/cGMP/K. The local administration of montelukast into the hind paw produced dose-related analgesia during both phases of the formalin test. Furthermore, pre-treatment with L-NAME, methylene blue, and glibenclamide prevented montelukast (10 μg/paw)-induced antinociception in both early and late phases of the test. Moreover, the local L-arginine and diazoxide before the sub-effective dose of montelukast (3 μg/paw) produced an analgesic effect. Also, local GW-9662 blocked antinociception induced by montelukast plus pioglitazone (10 μg/paw).. In conclusion, montelukast produced peripheral analgesia through PPARγ receptors and activation of the L-arginine/NO/cGMP/K

Topics: Acetates; Analgesia; Analgesics; Animals; Arginine; Behavior, Animal; Cyclic GMP; Cyclopropanes; Disease Models, Animal; KATP Channels; Leukotriene Antagonists; Male; Nitric Oxide; Nociceptive Pain; PPAR gamma; Quinolines; Rats, Wistar; Signal Transduction; Sulfides

Montelukast is a leukotriene receptor antagonist that is known to prevent allergic rhinitis and asthma. Blocking the Cysteinyl leukotriene receptor (CysLTR1), one of the primary receptors of leukotrienes, has been demonstrated to be efficacious in ameliorating experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), through disrupting chemotaxis of infiltrating T cells. However, the role of CysLTR1 in the pathogenesis of MS is not well understood. Here, we show that MS patients had higher expression of CysLTR1 in the circulation and central nervous system (CNS). The majority of CD4

Topics: Acetates; Adoptive Transfer; Animals; Anti-Inflammatory Agents; Cell Differentiation; Cyclopropanes; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Female; Humans; Inflammation; Leukotriene Antagonists; Mice; Mice, Inbred C57BL; Molecular Targeted Therapy; Multiple Sclerosis; Quinolines; Receptors, Leukotriene; Signal Transduction; Sulfides; Th17 Cells

Male reproductive dysfunction is one of the overlooked findings of diabetes mellitus (DM) that deserves greater scientific attention. This study is designed to explore the therapeutic potential of metformin and montelukast, in combination with Lactobacillus, for modulation of intestinal flora and suppression of oxidative stress in testicular and liver damage in diabetic male rats. A DM model was induced by streptozotocin (STZ)which caused functional, biochemical, and inflammatory injuries to the testicular and liver tissues. The experimental panel included nine rat groups: normal control, normal control plus metformin, normal control plus montelukast, DM control, DM plus montelukast, DM plus a combination of metformin and Lactobacillus, DM plus a combination of montelukast and Lactobacillus, and DM plus a combination of metformin and montelukast. In parallel, clinical evaluation of microscopic examination scoring, and hepatic and testicular injuries, were evaluated. Biochemical markers including glucose level, lipid profile, inflammatory markers (tumor necrosis factor- (TNF-α) and interleukin-17 (IL-17), Caspase-3, and Bax proteins expressions were measured. The change in the microbiota abundance was investigated using conventional and real-time PCR. The current study revealed a significant difference in the relative abundance of microbiota, where DM is associated with an enormous increase of Bacteroides spp., Clostridium spp., E. coli, and Fusobacterium spp., and a significant decrease in Bifidobacteria spp., and Lactobacillus spp., in contrast with normal control. Metformin and montelukast, in combination with Lactobacillus, significantly reversed the testicular and liver damage caused by STZ. Moreover, the drugs significantly reduced the oxidative, inflammatory, and apoptotic activities induced by STZ.

Topics: Acetates; Animals; Cyclopropanes; Cytochrome P-450 CYP1A2 Inducers; Diabetes Complications; Diabetes Mellitus, Experimental; Disease Models, Animal; Drug Therapy, Combination; Gastrointestinal Microbiome; Hypoglycemic Agents; Inflammation; Lactobacillus; Male; Metformin; Oxidative Stress; Quinolines; Rats; Rats, Sprague-Dawley; Sulfides

Dementia with Lewy bodies (DLB) represents a huge medical need as it accounts for up to 30% of all dementia cases, and there is no cure available. The underyling spectrum of pathology is complex and creates a challenge for targeted molecular therapies. We here tested the hypothesis that leukotrienes are involved in the pathology of DLB and that blocking leukotrienes through Montelukast, a leukotriene receptor antagonist and approved anti-asthmatic drug, might alleviate pathology and restore cognitive functions. Expression of 5-lipoxygenase, the rate-limiting enzyme for leukotriene production, was indeed elevated in brains with DLB. Treatment of cognitively deficient human alpha-synuclein overexpressing transgenic mice with Montelukast restored memory. Montelukast treatment resulted in modulation of beclin-1 expression, a marker for autophagy, and in a reduction in the human alpha-synulcein load in the transgenic mice. Reducing the protein aggregation load in neurodegenerative diseases might be a novel model of action of Montelukast. Moreover, this work presents leukotriene signaling as a potential drug target for DLB and shows that Montelukast might be a promising drug candidate for future DLB therapy development.

Topics: Acetates; alpha-Synuclein; Animals; Cyclopropanes; Disease Models, Animal; Female; Humans; Leukotriene Antagonists; Lewy Body Disease; Memory; Memory Disorders; Mice; Mice, Transgenic; Quinolines; Receptors, Leukotriene; Sulfides

Nasal obstruction is one of the most bothersome symptoms of allergic rhinitis (AR) affecting sleep-related quality of life in AR patients. Although several treatments were tested to control nasal obstruction, some patients with moderate to severe AR do not respond to current treatments, including the combined administration of different types of anti-allergic medicine. Thus, new options for AR treatment are needed. This study aimed to evaluate the effects of combined treatment with a novel inhibitor of hematopoietic prostaglandin D synthase (HPGDS), TAS-205, and different types of anti-allergic medicine on nasal obstruction in AR. Firstly, we demonstrated that TAS-205 selectively inhibited prostaglandin D

Topics: Acetates; Animals; Anti-Allergic Agents; Cell Line; Cyclopropanes; Disease Models, Animal; Drug Synergism; Drug Therapy, Combination; Enzyme Inhibitors; Guinea Pigs; Humans; Intramolecular Oxidoreductases; Lipocalins; Male; Morpholines; Nasal Mucosa; Nasal Obstruction; Ovalbumin; Piperidines; Prostaglandin D2; Pyrroles; Quality of Life; Quinolines; Rats; Rhinitis, Allergic; Sulfides; Terfenadine

The cysteinyl leukotrienes (CysLTs), i.e. LTC

Topics: Acetates; Animals; Anti-Inflammatory Agents, Non-Steroidal; Bile Acids and Salts; Colitis; Cyclopropanes; Disease Models, Animal; Gene Expression; Genes, Reporter; HEK293 Cells; Hep G2 Cells; Humans; Leukotriene Antagonists; Leukotriene C4; Leukotriene D4; Leukotriene E4; Luciferases; Mice; Mice, Knockout; Molecular Docking Simulation; Quinolines; RAW 264.7 Cells; Receptors, G-Protein-Coupled; Receptors, Leukotriene; Recombinant Fusion Proteins; Sulfides

Montelukast sodium is an effective and well-tolerated anti-asthmatic drug. Long non-coding RNAs (lncRNAs) are involved in the treatment of asthma. Therefore, this study aimed to investigate the effect of montelukast sodium on children with cough-variant asthma (CVA) and the role of lncRNA prostate cancer gene expression marker 1 (PCGEM1) in drug efficacy. The efficacy of montelukast sodium was evaluated by assessing the release of inflammatory factors and pulmonary function in CVA children after a 3-month treatment. An ovalbumin (OVA)-sensitized mouse model was developed to simulate asthmatic conditions. PCGEM1 expression in clinical peripheral blood samples and lung tissues of asthmatic mice was determined. Asthmatic mice experienced nasal inhalation of PCGEM1 overexpression with simultaneous montelukast sodium to investigate the roles of PCGEM1 in asthma treatment. The NF-κB axis after PCGEM1 overexpression was detected to explore the underling mechanisms. Consequently, montelukast sodium contributed to reduced levels of pro-inflammatory factors and improved pulmonary function in CVA children. PCGEM1 was poorly expressed in OVA-sensitized asthmatic mice and highly expressed in CVA children with response to the treatment. PCGEM1 overexpression enhanced the anti-inflammatory effects and promoted effects on pulmonary function of montelukast sodium in CVA children and OVA-sensitized asthmatic mice. Furthermore, PCGEM1 inhibited the activation of the NF-κB axis. This study demonstrated the anti-inflammatory and lung-protective effects of montelukast sodium on CVA, which was strengthened by overexpression of PCGEM1. Findings in this study highlighted a potential anti-asthmatic target of montelukast sodium.

Topics: Acetates; Animals; Anti-Asthmatic Agents; Asthma; Child; Child, Preschool; Cough; Cyclopropanes; Disease Models, Animal; Female; Humans; Male; Mice; Mice, Inbred BALB C; Protective Agents; Quinolines; RNA, Long Noncoding; Sulfides

The present study investigated the role of montelukast (MK) during the progression of bronchopulmonary dysplasia (BPD) and the underlying mechanism of action. A rat model of BPD was induced by hyperoxia and subsequently, the rats were treated with 10 mg/kg MK. On day 14 post‑hyperoxia induction, lung function was assessed by detecting the mean linear intercept (MLI; the average alveolar diameter), the radial alveolar count (RAC; alveolar septation and alveologenesis) and the lung weight/body weight (LW/BW) ratio. Type II alveolar epithelial (AEC II) cells were isolated from normal rats to investigate the mechanism underlying the effect of MK on BPD in vitro. Western blotting and reverse transcription‑quantitative PCR were performed to measure the expression levels of surfactant protein C (SP‑C), E‑cadherin, N‑cadherin, Vimentin, collagen I (Col I), matrix metallopeptidase (MMP)1/3, transforming growth factor (TGF)‑β1 and Smad3. MK significantly reduced the MLI and the LW/BW ratio, and increased the RAC of the BPD group compared with the control group. MK upregulated the expression of SP‑C and E‑cadherin, and downregulated the expression levels of N‑cadherin and Vimentin in the lung tissues of the rat model of BPD, as well as in TGF‑β1‑ and hyperoxia‑induced AEC II cells. In addition, MK reduced the expression of Col I, MMP1, MMP3, TGF‑β1 and Smad3 in the lung tissues of the rat model of BPD, as well as in TGF‑β1‑ and hyperoxia‑induced AEC II cells. The present study demonstrated that MK improved BPD by inhibiting epithelial‑mesenchymal transition via inactivating the TGF‑β1/Smads signaling pathway.

Topics: Acetates; Alveolar Epithelial Cells; Animals; Bronchopulmonary Dysplasia; Cell Hypoxia; Cyclopropanes; Disease Models, Animal; Epithelial-Mesenchymal Transition; Gene Expression Regulation; Quinolines; Rats; Signal Transduction; Smad Proteins; Sulfides; Transforming Growth Factor beta1

While bronchodilators and inhaled corticosteroids are the mainstay of asthma treatment, up to 50% of asthmatics remain uncontrolled. Many studies show that the cysteinyl leukotriene cascade remains highly activated in some asthmatics, even those on high-dose inhaled or oral corticosteroids. Hence, inhibition of the leukotriene C4 synthase (LTC4S) enzyme could provide a new and differentiated core treatment for patients with a highly activated cysteinyl leukotriene cascade. Starting from a screening hit (

Topics: Administration, Oral; Animals; Anti-Asthmatic Agents; Asthma; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Discovery; Enzyme Inhibitors; Glutathione Transferase; Humans; Molecular Structure; Pyrazines; Rats; Structure-Activity Relationship

Montelukast is an anti-asthmatic medication, and has recently showed its inhibitory effects on the proliferation of cancers. The purpose of this study was to identify the cytotoxic effects of montelukast on multiple myeloma (MM) cells and the combination effects of montelukast and carfilzomib in the treatment of MM. Results revealed that montelukast induced a dose- and time-dependent cytotoxicity in MM cells lines and significantly suppressed the colony formation of myeloma cells. Furthermore, montelukast enhanced the cytotoxicity of carfilzomib in MM cell lines. This anti-tumor effect was associated with decreased c-Myc via the inhibition of mTOR signaling pathway. Moreover, the combination of montelukast and carfilzomib induced apoptosis of myeloma cells effectively, even in the presence of bone marrow stromal cells (BMSCs). It is more important to note that the co-treatment exhibited similar cytocidal effects in carfilzomib-resistant cell lines (U266R and 8226R). In addition, the combined effects were noted in two MM xenograft mice models and 7 cases of human CD138

Topics: Acetates; Animals; Anti-Asthmatic Agents; Cell Line, Tumor; Cyclopropanes; Disease Models, Animal; Humans; Mice; Multiple Myeloma; Oligopeptides; Quinolines; Sulfides; TOR Serine-Threonine Kinases; Transfection; Xenograft Model Antitumor Assays

In this study, our aim was to identify the possible effects of montelukast sodium (ML) on the prevention of experimentally induced myringosclerosis.. Twenty-eight female Wistar albino rats were used and they were divided into four groups randomly. Tympanic membranes (TM) of all animals were perforated and then group 1 received no treatment (control group), group 2 was treated with a topical saline solution, group 3 received topically ML and group 4 received orally ML. On the 15th day, all animals were euthanized. Tympanic membranes were evaluated otomicroscopically and histopathologically.. The histopathological findings, compared against a control and saline groups, showed the topically and orally ML groups had statistically significant differences of degree of myringosclerosis (p < 0.002) and median thickness of the TMs (p < 0.001). Suppression of inflammation was statistically significant only in the oral ML treatment group (p < 0.002).. Oral and topically administration of ML reduced myringosclerosis formation in myringotomies rats.

Topics: Acetates; Animals; Cyclopropanes; Cytochrome P-450 CYP1A2 Inducers; Disease Models, Animal; Female; Middle Ear Ventilation; Myringosclerosis; Quinolines; Rats; Rats, Wistar; Sulfides; Tympanic Membrane

Identification of the characterization of cysteinyl leukotrienes receptor (CysLTRs) could facilitate our understanding of these receptors' role in asthma. We aimed to investigate the localization and interactions of CysLTRs using a mouse model of asthma. BALB/c mice were administered ovalbumin (OVA) to induce allergic asthma. Some mice were administered the antagonists of CysLTR1, CysLTR2, and purinergic receptor P2Y12 (P2Y12R) (montelukast, HAMI 3379 and clopidogrel, respectively). The expression levels of CysLTR1, CysLTR2, and P2Y12R on lung tissues and inflammatory cells were evaluated by western blot, flow cytometry, and immunochemistry. CysLTR1 and P2Y12R were significantly up-regulated in lung tissues (P < 0.05 for each) from mouse after being sensitized and challenged with OVA (OVA/OVA). The ratio of CysLTR1: CysLTR2: P2Y12R in lungs of negative control (NC) mice was shifted from 1:0.43:0.35 to 1:0.65:1.34 in OVA/OVA mice. Montelukast significantly diminished the up-regulation of CysLTR1, CysLTR2, and P2Y12R (P < 0.05 for each), while the effects of HAMI 3379 and clopidogrel were predominant on the expression of CysLTR2 and P2Y12R, respectively. Montelukast predominantly diminished the cell count, while clopidogrel potently inhibited the release of interleukin (IL)-4, IL-5, and IL-13. Our study demonstrated the interactions between CysLTRs, thereby highlighting the potential synergistic effects of CysLTR antagonists in asthma treatment.

Topics: Acetates; Animals; Asthma; Clopidogrel; Cyclohexanecarboxylic Acids; Cyclopropanes; Disease Models, Animal; Drug Therapy, Combination; Eosinophils; Female; Inflammation; Interleukins; Leukotriene Antagonists; Mice; Mice, Inbred BALB C; Ovalbumin; Phthalic Acids; Purinergic P2Y Receptor Antagonists; Quinolines; Receptors, Leukotriene; Receptors, Purinergic P2Y12; Sulfides; Th2 Cells

BACKGROUND Bronchopulmonary dysplasia (BPD) is a chronic lung disease common in preterm infants. Montelukast, an effective cysteinyl leukotriene (cysLT) receptor antagonist, has a variety of pharmacological effects and has protective effects against a variety of diseases. Currently, the efficacy and safety of montelukast sodium in treating BPD has been revealed, however, the precise molecular mechanism of the effect of montelukast on BPD development remain largely unclear. Therefore, this study aimed to investigate the effect and mechanism of montelukast on BPD in vivo and in vitro. MATERIAL AND METHODS A mouse BPD model and hyperoxia-induced lung cell injury model were established and treated with montelukast. Then mean linear intercept (MLI), radial alveolar count (RAC), lung weight/body weight (LW/BW) ratio, pro-inflammatory factors, and oxidative stress-related factors in lung tissues were determined. Cell viability and apoptosis were detected using MTT assay and flow cytometer respectively. RESULTS The results showed that montelukast treatment relieved mouse BPD, evidenced by increased RAC and decreased MLI and LW/BW ratios. We also found that montelukast treatment reduced pro-inflammatory factors (TNF-alpha, IL-6, and IL-1ß) production, enhanced superoxide dismutase (SOD) activity, and reduced malondialdehyde (MDA) content in the lung tissues of BPD mice. Besides, montelukast eliminated the reduced cell viability and enhanced cell apoptosis induced by hyperoxia exposure in vitro. Moreover, the upregulated pro-inflammatory factors production and p-p65 protein level in lung cells caused by hyperoxia were decreased by montelukast treatment. CONCLUSIONS Montelukast protected against mouse BPD induced by hyperoxia through inhibiting inflammation, oxidative stress, and lung cell apoptosis.

Topics: Acetates; Animals; Animals, Newborn; Apoptosis; Bronchopulmonary Dysplasia; Cyclopropanes; Disease Models, Animal; Hyperoxia; Interleukin-1beta; Interleukin-6; Lung; Lung Injury; Mice; Mice, Inbred C57BL; Oxidative Stress; Quinolines; Receptors, Leukotriene; Sulfides; Tumor Necrosis Factor-alpha

Topics: Acetates; Animals; Anti-Bacterial Agents; Cefazolin; Cyclopropanes; Cytokines; Disease Models, Animal; Inflammation; Leukotriene Antagonists; Male; Nasal Septum; Quinolines; Rats; Rats, Wistar; Rhinitis; Sinusitis; Staphylococcal Infections; Staphylococcus aureus; Sulfides; Treatment Outcome; Turbinates

Cysteinyl-leukotrienes (cys-LTs) are 5-lipoxygenase-derived lipid mediators involved in the pathogenesis and progression of inflammatory disorders, in particular asthma. We have previously found evidence linking these mediators to increased levels of proteolytic enzymes in tissue specimens of human abdominal aortic aneurysm (AAA). Here we show that antagonism of the CysLT1 receptor by montelukast, an established antiasthma drug, protects against a strong aorta dilatation (>50% increase = aneurysm) in a mouse model of CaCl

Topics: Acetates; Angiotensin II; Animals; Aortic Aneurysm, Abdominal; Chemokine CCL3; Cyclopropanes; Disease Models, Animal; Leukotriene Antagonists; Matrix Metalloproteinase 9; Mice; Mice, Knockout, ApoE; Quinolines; Receptors, Leukotriene; Sulfides

Asthma is characterized by airway hyperresponsiveness (AHR) and inflammation leading to airway remodeling (AR). In children, AR may occur very early prior to the age of 6 years. Treatments to prevent or reverse AR are unknown.. We sought to determine (i) whether short allergenic sensitization at a young age in a mouse model may induce enhanced AR and inflammation compared to adults; (ii) the effect of Montelukast on such AR.. Immature and adult Balb/c mice were sensitized and challenged with ovalbumin. AHR and AR were measured using cultured precision-cut lung slices and inflammation by bronchoalveolar lavage. Experiments were repeated after administration of Montelukast.. OVA-challenged mice developed AHR to methacholine regardless of age of first exposure to OVA. Young mice developed greater thickened basement membrane, increased smooth muscle mass, and increased area of bronchovascular fibrosis compared with adult mice. Cellular infiltrates in BAL differed depending upon animal age at first exposure with higher eosinophilia measured in younger animals. Montelukast decreased ASM mass, BAL cellularity.. We provide thus evidence for a greater degree of AR after allergenic sensitization and challenge in younger mice versus adults. This study provides proof of concept that airway remodeling can be prevented and reversed in this case by anti-asthmatic drug Montelukast in this model.

Topics: Acetates; Age Factors; Airway Remodeling; Allergens; Animals; Anti-Asthmatic Agents; Asthma; Bronchoalveolar Lavage Fluid; Cyclopropanes; Disease Models, Animal; Female; Lung; Mice, Inbred BALB C; Ovalbumin; Quinolines; Sulfides

We have recently demonstrated that T cell-mediated nasal hyperresponsiveness (NHR) is a representative pathophysiological feature of allergic rhinitis (AR). Although several anti-allergic drugs are used for the treatment of AR, the efficacy of these drugs on T cell-mediated NHR have not been elucidated. In these studies we investigated the effects of dexamethasone (Dex), montelukast (Mk), and chlorpheniramine (Chl) on NHR in antigen-immunized and antigen-specific Th2 cell-transferred mice.. OVA-immunized BALB/c mice were treated with Dex, Mk, or Chl and challenged intranasally with OVA. We then assessed NHR, the number of inflammatory cells in the nasal lavage fluid (NALF), mRNA expression of Th2 cytokines in the nasal tissue, the population of CD3. Dex significantly suppressed antigen-induced NHR, inflammatory cell infiltration, and IL-4, IL-5, IL-6, and IL-13 expression in immunized mice. Chl was completely ineffective, and only IL-13 expression was suppressed by Mk. None of these drugs affected IgE and IgG production. Antigen-induced NHR and the increase in antigen-specific T cells in the NALT of Th2 cell-transferred mice were inhibited by Dex, but not by Mk or Chl.. Steroids are effective for the reduction of NHR in AR by suppressing the accumulation of inflammatory cells, especially antigen-specific T cells.

Topics: Acetates; Animals; Anti-Allergic Agents; CD4-Positive T-Lymphocytes; Chlorpheniramine; Cyclopropanes; Cytokines; Dexamethasone; Disease Models, Animal; Female; Immunoglobulin E; Immunoglobulin G; Mice; Mice, Inbred BALB C; Nasal Lavage Fluid; Nasal Mucosa; Quinolines; Rhinitis, Allergic; Sulfides

Obstructive sleep apnea (OSA) characterized by nocturnal intermittent hypoxia (IH) is associated with atherosclerosis and cysteinyl-leukotrienes (CysLT) pathway activation. We aimed to identify the determinants of CysLT pathway activation and the role of CysLT in OSA-related atherosclerosis.. Determinants of the urinary excretion of LTE. IH-related CysLT pathway activation contributes to OSA-induced atherogenesis. In the era of personalized medicine, U-LTE

Topics: 5-Lipoxygenase-Activating Proteins; Acetates; Adult; Animals; Arachidonate 5-Lipoxygenase; Atherosclerosis; Case-Control Studies; Cyclopropanes; Cysteine; Disease Models, Animal; Disease Progression; Female; Humans; Leukotriene Antagonists; Leukotriene E4; Leukotrienes; Male; Mice, Knockout, ApoE; Middle Aged; Plaque, Atherosclerotic; Quinolines; Receptors, Leukotriene; Risk Factors; Signal Transduction; Sleep Apnea, Obstructive; Sulfides

To study the possible protective role of montelukast in endometrial hyperplesia (EH) rat model, induced by estradiol valerate (EV).. Thirty six female albino Wistar rats were classified into 7 groups: normal control, EV (2 mg/kg/day, p.o.), montelukast (10 mg/kg/day, p.o.), montelukast (1 mg/kg/day, p.o.) + EV (2 mg/kg/day, p.o.), montelukast (10 mg/kg/day, p.o.) + EV (2 mg/kg/day, p.o.), montelukast (20 mg/kg/day, p.o.) + EV (2 mg/kg/day, p.o.) groups. Uterine malondialdehyde (MDA), superoxide dismutase (SOD), total nitrites (NO) and serum total antioxidant capacity (TAC) were determined. Uterine, serum total cholesterol, high density lipoprotein (HDL) and tumor necrosis factor (TNF)-α were measured. Histopathological examination of the uterine tissue was also done. In addition, immunohistochemistry was done using Phosphatase and tensin homolog (PTEN) and inducible nitric oxide synthase (iNOS) antibodies.. Our results showed that montelukast in dose dependant manner improves oxidative stress, lipids profile and TNF α which were affected by EV. Moreover, immunohistochemical examination revealed that montelukast markedly reduced iNOS expression, while expression of PTEN was markedly enhanced, as compared to EV group. The protective effects of montelukast were also verified histopathologically.. Montelukast in dose dependant manner provided biochemical and histo-pathological improvement in EV induced EH, through its anti-inflammatory, antioxidant activity and inhibition of iNOS expression with induction of PTEN expression.

Topics: Acetates; Animals; Anti-Inflammatory Agents; Antioxidants; Cholesterol; Cyclopropanes; Disease Models, Animal; Dose-Response Relationship, Drug; Endometrial Hyperplasia; Estradiol; Female; Nitric Oxide Synthase Type II; Oxidative Stress; Quinolines; Rats; Rats, Wistar; Sulfides; Tumor Necrosis Factor-alpha

Viral infections are the most common triggers of asthma exacerbation, but the key molecules involved in this process have not been fully identified. Although cysteinyl leukotrienes (cysLTs) have been postulated as the key mediators, their precise roles remain largely unclear. To investigate the roles of cysLTs in virus-induced asthma exacerbation, we developed a murine model using a viral double-stranded RNA analog, polyinosinic-polycytidylic acid (poly I:C), and analyzed the effect of leukotriene receptor antagonist (LTRA) administration.. A/J mice were immunized with ovalbumin (OVA) + alum (days 0, 28, 42, and 49), followed by intranasal challenge with OVA (phase 1: days 50-52) and poly I:C (phase 2: days 53-55). Montelukast was administered during poly I:C challenge (phase 2) in the reliever model or throughout the OVA and poly I:C challenges (phases 1 and 2) in the controller model. Airway responsiveness to acetylcholine chloride was assessed, and bronchoalveolar lavage (BAL) was performed on day 56.. Administration of poly I:C to OVA-sensitized and -challenged mice increased the number of eosinophils and levels of IL-13, IL-9, CCL3, and CXCL1 in BAL fluid (BALF) and tended to increase airway responsiveness. Montelukast significantly attenuated the poly I:C-induced increase in the number of eosinophils and levels of IL-13, IL-9, and CCL3 in BALF and airway hyperresponsiveness in both the reliever and controller models.. This is the first report showing that LTRA functionally suppressed the pathophysiology of a virus-induced asthma exacerbation model, suggesting the importance of cysLTs as a potential treatment target.

Topics: Acetates; Alum Compounds; Animals; Anti-Asthmatic Agents; Asthma; Bronchoalveolar Lavage Fluid; Cyclopropanes; Cysteine; Cytokines; Disease Models, Animal; Disease Progression; Eosinophils; Immunization; Inflammation Mediators; Leukotriene Antagonists; Leukotrienes; Male; Mice; Ovalbumin; Poly I-C; Quinolines; Respiratory Hypersensitivity; RNA, Double-Stranded; RNA, Viral; Sulfides

Topics: Acetates; Active Transport, Cell Nucleus; Animals; Antineoplastic Agents; Apoptosis; Apoptosis Inducing Factor; Biomarkers; Cell Death; Cell Line, Tumor; Cell Proliferation; Cyclopropanes; Disease Models, Animal; Humans; Leukotriene Antagonists; Lung Neoplasms; Models, Biological; Protein Transport; Quinolines; Signal Transduction; Sulfides; Tumor Burden; Xenograft Model Antitumor Assays

Topics: Acetates; Animals; Anti-Inflammatory Agents; Chemokine CCL2; Cyclopropanes; Disease Models, Animal; Dose-Response Relationship, Drug; E-Selectin; Estradiol; Gene Expression Regulation; Inflammation Mediators; Interleukin-6; Leukotriene Antagonists; Leukotriene B4; Male; NF-kappa B; Nitric Oxide Synthase Type II; Orchiectomy; Prostate; Prostatitis; Quinolines; Rats, Wistar; Receptors, Leukotriene; Sulfides; Time Factors; Tumor Necrosis Factor-alpha

Although the main cause of degeneration of the nigrostriatal dopaminergic (DA) projection in Parkinson's disease (PD) is still controversial, many reports suggest that excessive inflammatory responses mediated by activated microglia can induce neurotoxicity in the nigrostriatal DA system in vivo. Montelukast, which plays an anti-inflammatory role, is used to treat patients with asthma. In addition, recent studies have reported that its administration could reduce neuroinflammatory activities, showing beneficial effects against various neuropathological conditions. These results suggest that montelukast may be a useful drug to alleviate inflammatory responses in PD, even though there are no reports showing its beneficial effects against neurotoxicity in the nigrostriatal DA system. In the present study, our results showed that treatment with montelukast could protect DA neurons against 6-hydroxydopamine (6-OHDA)-induced neurotoxicity and its administration significantly attenuated the production of neurotoxic cytokines such as tumor necrosis factor-α (TNFα) and interleukin-1β (IL-1β) from activated microglia in the substantia nigra (SN) and striatum following 6-OHDA treatment. Therefore, we suggest that montelukast can be used as a potential inhibitor of microglial activation to protect DA neurons in the adult brain against PD.

Topics: Acetates; Adrenergic Agents; Animals; Calcium-Binding Proteins; Cyclopropanes; Cytokines; Disease Models, Animal; Dopaminergic Neurons; Dose-Response Relationship, Drug; Male; Mice; Mice, Inbred C57BL; Microfilament Proteins; Microglia; Neuroprotective Agents; Oxidopamine; Parkinson Disease; Quinolines; Rotarod Performance Test; Substantia Nigra; Sulfides; Tyrosine 3-Monooxygenase

This study aims to investigate the acute protective effect of montelukast sodium in hepatic injury secondary to acetaminophen (APAP) intoxication. This study used 60 rats. The rats were grouped into 6 groups. The control group was administered oral distilled water 10 ml/kg, the APAP group oral APAP 1 g/kg, the montelukast sodium (MK) group oral MK 30 mg/kg, the acetaminophen+N-acetylcysteine (APAP+NAC) group oral APAP 1 g/kg, followed by a single dose of intraperitoneal NAC 1.5 g/kg three hours later, the acetaminophen+montelukast sodium (APAP+MK) group oral APAP 1 g/kg, followed by oral MK 30 mg/kg 3 h later, the acetaminophen+N-acetylcysteine+montelukast sodium (APAP+NAC+MK) group oral APAP 1 g/kg, followed by a single intraperitoneal NAC 1.5 g/kg plus oral MK 30 mg/kg 3 h later. Blood and liver tissue samples were taken 24h after drug administration. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and total bilirubin were studied from the blood samples. Liver tissue samples were used for histopathological examination. Compared with the control group, serum AST and ALT activities were higher in the APAP and APAP+NAC groups. APAP+NAC, APAP+MK, and APAP+NAC+MK groups had reduced serum ALT and AST activities than the group administered APAP alone. APAP+MK and APAP+NAC+MK groups had a lower serum ALP activity than the control group. Histopathologically, there was a difference between the group administered APAP alone and the APAP+MK and APAP+NAC+MK groups. MK is as protective as NAC in liver tissue in APAP intoxication in rats.

Topics: Acetaminophen; Acetates; Acetylcysteine; Analgesics, Non-Narcotic; Animals; Chemical and Drug Induced Liver Injury; Cyclopropanes; Cytochrome P-450 CYP1A2 Inducers; Disease Models, Animal; Free Radical Scavengers; Male; Quinolines; Rats; Rats, Wistar; Sulfides

Chronic cerebral hypoperfusion (CCH) is a general pathophysiological condition occurring in vascular dementia (VaD) associated with negative impact on cognitive functions. Ryanodine as well as cysteinyl leukotriene-1 receptors (RyRs and CysLT1Rs) are extensively present in the central nervous system, where they participate in regulation of cognition, motivation, inflammation and neurodegeneration. The purpose of this study is to examine the role of ruthenium red; a selective RyR blocker as well as montelukast; a specific CysLT1 antagonist in CCH induced VaD in mice. Two vessel occlusion (2VO) or permanent ligation of bilateral common carotid arteries technique was used to induce CCH in mice. Animals with bilateral carotid arteries occlusion have revealed impaired learning and memory (Morris water maze), cholinergic dysfunction (increased acetylcholinesterase activity) as well as increased brain oxidative stress (reduction in brain superoxide dismutase, glutathione and catalase with an increase in thiobarbituric acid reactive substance level), with increased brain infarct size (2,3,5-triphenylterazolium chloride staining). While, administration of ruthenium red and montelukast considerably attenuated CCH induced cognitive impairments, cholinergic dysfunction, brain oxidative stress as well as brain damage. The results suggest that bilateral carotid arteries occlusion induced CCH has brought out VaD, which was attenuated by treatment with ruthenium red and montelukast. Therefore, modulation of RyRs as well as CysLT1 receptors may provide help in conditions involving CCH such as cognitive impairment and VaD.

Topics: Acetates; Animals; Carotid Artery Diseases; Cerebral Cortex; Cholinergic Agents; Cognition Disorders; Cyclopropanes; Disease Models, Animal; Glutathione; Leukotriene Antagonists; Lipid Peroxidation; Male; Mice; Oxidative Stress; Oxidoreductases; Quinolines; Receptors, Leukotriene; Ruthenium Red; Ryanodine Receptor Calcium Release Channel; Sulfides; Time Factors

Airway inflammation in chronic obstructive pulmonary disease (COPD) is refractory to corticosteroids and hence COPD treatment is hindered and insufficient. This study assessed the effects of oral treatment with Montelukast (10 and 30 mg/kg) or dexamethasone (20 mg/kg) for 20 days on COPD model induced by chronic exposure to lipopolysaccharide (LPS). Six groups of male guinea pigs were studied. Group 1: naïve group, group 2: exposed to saline nebulization. Groups 3, 4, 5, and 6: exposed to 9 nebulizations of LPS (30 μg/ml) for 1 hour, 48 hours apart with or without treatment with Montelukast or dexamethasone. Airway hyperreactivity (AHR) to methacholine (MCh), histopathological study and bronchoalveolar lavage fluid (BALF) as well as lung tissue analyses were performed 48 hours after the final exposure to LPS (day 20). LPS-induced pulmonary dysfunction was associated with increased neutrophil count, leukotriene (LT) B4, and tumor necrosis factor (TNF)-α in BALF. Moreover, there was an increase in malondialdehyde (MDA) level and a decrease in histone deacetylases(HDAC) activity in the lung tissue. Both Montelukast (10 or 30 mg /kg) and dexamethasone significantly reduced neutrophil count in BALF and inflammatory cells in lung parenchyma as well as TNF-α, and MDA levels. However, dexamethasone was more effective (p < 0.05). Montelukast, at a dose of 30 mg /kg, significantly reduced specific airway resistance after the 9th LPS exposure, attenuated AHR to MCh, decreased LTB4 and increased HDAC activity in comparison to dexamethasone. These results suggest that treatment with Montelukast can be useful in chronic airway inflammatory diseases including COPD poorly responsive to glucocorticoids.

Topics: Acetates; Animals; Bronchoalveolar Lavage Fluid; Chronic Disease; Cyclopropanes; Dexamethasone; Disease Models, Animal; Glucocorticoids; Guinea Pigs; Histone Deacetylases; Inflammation; Leukocyte Count; Leukotriene Antagonists; Leukotriene B4; Lipopolysaccharides; Lung; Male; Malondialdehyde; Neutrophils; Pulmonary Disease, Chronic Obstructive; Quinolines; Respiratory Hypersensitivity; Sulfides; Tumor Necrosis Factor-alpha

This study aimed to investigate the involvement of opioid receptors in the systemic and peripheral antinociceptive activities of montelukast in different animal models of pain. Rats and mice were injected with montelukast to produce analgesia. The formalin and acetic acid-induced writhing tests were used to assess the nociceptive activity. The results showed that i.p. administration of montelukast (0.3-10mg/kg) dose-dependently reduced flinching behavior in both the first and second phases of formalin test with mean ED50 of 0.55 and 5.31mg/kg, respectively. Also, intraplantar administration of montelukast (3-30μg/paw) produced antinociception against the two phases of formalin assay in a dose-dependent way with mean ED30 of 2.92 and 8.11μg/paw, respectively. Furthermore, pre-treatment with naloxone (a non-selective opioid receptor antagonist) significantly inhibited both the systemic and also peripheral antinociceptive actions of montelukast in formalin test. In writhing test, the results showed that intraperitoneal administration of montelukast (3-10mg/kg) significantly reduced the writhe number induced by acetic acid in mice. Moreover, co-administration of non-effective doses of montelukast (0.3 and 1mg/kg; i.p.) and morphine (0.25mg/kg; i.p.) significantly decreased the writhes number induced by acetic acid. Also, this effect was naloxone-reversible. These findings suggest that the systemic and peripheral antinociception produced by montelukast were mediated through the opioid receptors in central and peripheral nervous systems. Moreover, combination of montelukast and morphine could be noted as a new strategy for pain relief.

Topics: Acetates; Acetic Acid; Analgesics; Animals; Behavior, Animal; Cyclopropanes; Disease Models, Animal; Drug Synergism; Formaldehyde; Male; Mice; Naloxone; Pain; Quinolines; Rats; Receptors, Opioid; Sulfides; Visceral Pain

Pathological ocular neovascularization is a major cause of blindness. Increased dietary intake of ω-3 long-chain polyunsaturated fatty acids (LCPUFA) reduces retinal neovascularization and choroidal neovascularization (CNV), but ω-3 LCPUFA metabolites of a major metabolizing pathway, cytochrome P450 oxidase (CYP) 2C, promote ocular pathological angiogenesis. We hypothesized that inhibition of CYP2C activity will add to the protective effects of ω-3 LCPUFA on neovascular eye diseases.. The mouse models of oxygen-induced retinopathy and laser-induced CNV were used to investigate pathological angiogenesis in the retina and choroid, respectively. The plasma levels of ω-3 LCPUFA metabolites of CYP2C were determined by mass spectroscopy. Aortic ring and choroidal explant sprouting assays were used to investigate the effects of CYP2C inhibition and ω-3 LCPUFA-derived CYP2C metabolic products on angiogenesis ex vivo. We found that inhibition of CYP2C activity by montelukast added to the protective effects of ω-3 LCPUFA on retinal neovascularization and CNV by 30% and 20%, respectively. In CYP2C8-overexpressing mice fed a ω-3 LCPUFA diet, montelukast suppressed retinal neovascularization and CNV by 36% and 39% and reduced the plasma levels of CYP2C8 products. Soluble epoxide hydrolase inhibition, which blocks breakdown and inactivation of CYP2C ω-3 LCPUFA-derived active metabolites, increased oxygen-induced retinopathy and CNV in vivo. Exposure to selected ω-3 LCPUFA metabolites of CYP2C significantly reversed the suppression of both angiogenesis ex vivo and endothelial cell functions in vitro by the CYP2C inhibitor montelukast.. Inhibition of CYP2C activity adds to the protective effects of ω-3 LCPUFA on pathological retinal neovascularization and CNV.

Topics: Acetates; Angiogenesis Inhibitors; Animals; Aorta; Cells, Cultured; Choroidal Neovascularization; Cyclopropanes; Cytochrome P-450 CYP2C8; Cytochrome P-450 CYP2C8 Inhibitors; Disease Models, Animal; Endothelial Cells; Fatty Acids, Omega-3; Genotype; Humans; Hyperoxia; Lasers; Mice, Inbred C57BL; Mice, Transgenic; Neovascularization, Physiologic; Phenotype; Quinolines; Retinal Neovascularization; Retinopathy of Prematurity; Sulfides; Tissue Culture Techniques

BACKGROUND We evaluated the hematological, biochemical, and histopathological effects of Montelukast on pancreatic damage in an experimental acute pancreatitis model created by cerulein in rats before and after the induction of pancreatitis. MATERIAL AND METHODS Forty rats were divided into 4 groups with 10 rats each. The study groups were: the Cerulein (C) group, the Cerulein + early Montelukast (CMe) group, the Cerulein + late Montelukast (CMl) group, and the Control group. The pH, pO2, pCO2, HCO3, leukocyte, hematocrit, pancreatic amylase, and lipase values were measured in the arterial blood samples taken immediately before rats were killed. RESULTS There were statistically significant differences between the C group and the Control group in the values of pancreatic amylase, lipase, blood leukocyte, hematocrit, pH, pO2, pCO2, HCO3, and pancreatic water content, and also in each of the values of edema, inflammation, vacuolization, necrosis, and total histopathological score (P<0.05). When the CMl group and C group were compared, no statistically significant differences were found in any parameter analyzed. When the CMe group was compared with the C group, pancreatic amylase, lipase, pH, PO2, pCO2, HCO3, pancreatic water content, histopathological edema, inflammation, and total histopathological score values were significantly different between the groups (P<0.05). Finally, when the CMe group and the Control group were compared, significant differences were found in all except 2 (leukocyte and pO2) parameters (P<0.05). CONCLUSIONS Leukotriene receptor antagonists used in the late phases of pancreatitis might not result in any benefit; however, when they are given in the early phases or prophylactically, they may decrease pancreatic damage.

Topics: Acetates; Amylases; Animals; Ceruletide; Cyclopropanes; Disease Models, Animal; Edema; Leukotriene Antagonists; Lipase; Male; Pancreatitis; Quinolines; Rats; Rats, Sprague-Dawley; Sulfides

Topics: Acetates; Animals; Apoptosis; bcl-2-Associated X Protein; Caspase 3; Cognitive Dysfunction; Cyclopropanes; Disease Models, Animal; Hippocampus; Interleukin-1beta; Male; Maze Learning; Mice; Mice, Inbred ICR; Neurotoxicity Syndromes; Proto-Oncogene Proteins c-bcl-2; Quinolines; Receptors, Leukotriene; RNA, Messenger; Streptozocin; Sulfides; Tumor Necrosis Factor-alpha

Montelukast, a selective antagonist of Type 1 cysteinyl leukotriene receptors (CysLT1Rs), antagonizes the proinflammatory and proasthmatic activities of CysLT1Rs. We investigated the effect of montelukast on a surgically induced endometriosis rat model.. Thirty-two sexually mature, cycling, female Wistar-Albino rats, in which endometriotic implants were surgically induced, were randomly divided into three groups. Group I [Montelukast (M), 10 rats)] was given 1.6 mg/kg/day of oral montelukast sodium. Group II [Leuprolide acetate (L), 11 rats] was given 1 mg/kg single dose of s.c.leuprolide acetate. Group III [Control (C), 11 rats] received saline solution through an orogastric tube and served as controls. After a 3-weeks medication, the rats were sacrificed to investigate the endometriotic implants for size and morphological and histological characteristics, including immunoreactivity of MMP-2 and VEGF.. The mean area of implants decreased from 48.2 ± 24.7 to 29.3 ± 15.8mm(2) in Group I (M) (P = 0.008) and from 62 ± 32.1 to 39.9 ± 18.1mm(2) in Group II (L) (P=0.003). In Group III (C), the mean area increased from 41.1 ± 31.1 to 60.4 ± 37.1mm(2) (P = 0.025). Histopathological analysis showed statistically significant lower scores in rats treated with montelukast compared to leuprolide and controls. MMP H scores were not different between the groups in both epithelial and stromal MMP-2 immunostaining. VEGF H scores were statistically lower in Group 1 (M) in epithelial VEGF immunostaining when compared to Group II (L) and Group III (C) (P=0.006).. Montelukast may effectively cause a significant decrease in the area of endometriotic implants.

Topics: Acetates; Animals; Anti-Inflammatory Agents; Cyclopropanes; Disease Models, Animal; Endometriosis; Endometrium; Female; Leuprolide; Matrix Metalloproteinase 2; Quinolines; Rats; Rats, Wistar; Sulfides; Treatment Outcome; Vascular Endothelial Growth Factor A

We assessed the nephroprotective effects of montelukast sodium and N-acetylcysteine on secondary renal damage due to unilateral ureteral obstruction in a rat model.. In this study 30 Wistar albino male rats were randomized into 3 groups, including placebo, N-acetylcysteine and montelukast sodium. Three rats served as the control group. The left ureter of the rats was sutured with 4-zero polyglactin sutures. Medications were given 3 days before obstruction and continued for 15 days. Dimercaptosuccinic acid renal scintigraphy was performed before obstruction and on day 15. Rats were sacrificed on day 15 and histopathological examinations were done. We biochemically assessed oxidative stress markers (myeloperoxidase and malondialdehyde), sulfhydryl and total nitrite for lipid peroxidation, oxidative protein damage and antioxidant levels, respectively.. On pathological examination inflammation and tubular epithelial damage in the N-acetylcysteine and montelukast sodium groups were less than in the placebo group (p <0.05). No difference was seen in normal kidneys. Myeloperoxidase, malondialdehyde and total nitrite levels in the N-acetylcysteine group, and myeloperoxidase and malondialdehyde levels in the montelukast sodium group were lower than in the placebo group (p <0.05). No statistical difference was seen in sulfhydryl levels (p >0.05) or among the N-acetylcysteine, montelukast sodium and placebo groups on scintigraphy (p >0.05). No pathological, chemical and scintigraphic differences were seen among the N-acetylcysteine, montelukast sodium and sham treated groups (p >0.05).. N-acetylcysteine and montelukast sodium have a protective effect against obstructive damage of the kidney. However, further investigations are needed.

Topics: Acetates; Acetylcysteine; Animals; Cyclopropanes; Disease Models, Animal; Kidney Diseases; Male; Placebos; Quinolines; Randomized Controlled Trials as Topic; Rats; Rats, Wistar; Sulfides; Ureteral Obstruction

Allergic rhinitis (AR) is a global health problem that affects a large number of population. Piperine (PIP) has been reported to exhibit anti-inflammatory, anti-histaminic, and immunomodulatory activities; however, its antiallergic profile has not been studied.. The objective of the study was to investigate the antiallergic potential of PIP in ova-albumin (OVA)-induced AR, mast cell degranulation (MSD), and OVA-induced paw edema.. Mice were sensitized with OVA alternately on 1, 3, 5, 7, 9, 11, and 13th day. They were treated with either vehicle, PIP (10, 20, and 40 mg/kg, p.o.), or montelukast (10 mg/kg, p.o.) from the 14th to 20th day. On the 21st day, intranasal (OVA: 5% µl) challenge was done. Animals were evaluated for physiological parameters, biochemical parameters, spleen weight, expression of interleukins (IL-6 and IL-1β), and immunoglobin-E (IgE). Histopathology of nasal mucosa, lungs, and spleen was carried out. MSD and paw edema studies were made to understand the mechanism of action.. PIP (10, 20, and 40 mg/kg, p.o.) showed a significant dose-dependent protection with respect to nasal rubbing, redness of nose, and sneezing (p < 0.001) following nasal challenge. PIP dose dependently reduced histamine, NO concentration (p < 0.001), as well as reduced expression of IL-6, IL-1β, and IgE (p < 0.001) as compared with the control group. Histopathology showed inhibition of infiltration of eosinophils and hyperplasia. It dose dependently reduced MSD and paw edema (p < 0.001).. PIP acts by mast cell-stabilizing activity, exhibits immunomodulatory and anti-inflammatory activity, thereby providing an effective treatment for AR.

Topics: Acetates; Alkaloids; Animals; Anti-Allergic Agents; Benzodioxoles; Biomarkers; Cell Degranulation; Cyclopropanes; Disease Models, Animal; Dose-Response Relationship, Drug; Edema; Eosinophils; Histamine; Immunoglobulin E; Inflammation Mediators; Interleukin-1beta; Interleukin-6; Mast Cells; Nitric Oxide; Ovalbumin; Piperidines; Polyunsaturated Alkamides; Quinolines; Rhinitis, Allergic; Spleen; Sulfides; Time Factors

The aim of this study was to investigate the effect of montelukast on the expression of interleukin (IL)-18, telomerase reverse transcriptase (TERT), and Bcl-2 in the brain tissue of neonatal rats with hypox-ic-ischemic brain damage (HIBD). To establish the model of HIBD, 8% oxygen was applied to rats after the unilateral carotid artery was ligated. Twenty rats were randomly assigned to the control group, while another 40 were used to establish the HIBD model and were randomly divided equally into model group and treatment group. A 0.1 mg/kg dose of montelukast or an equal volume of saline was intraperitoneally injected to the rats in the treatment group and the model group, respectively. Brain tissue from 4 rats in each group was sampled at 0, 6, 12, 24, and 72 h after brain damage, and immunohistochemistry was used to measure IL-18, TERT and Bcl-2 expressions. IL-18, TERT, and Bcl-2 levels increased after 12 h in both the model group and treatment group, peaked after 48 h, and then decreased. Although not statistically significant, IL-18, TERT, and Bcl-2 expressions after 24, 48, and 96 h were all lower in the treatment group than those in the model group. In conclusion, montelukast has a protective effect on the cerebral tissue of neonatal rats with HIBD, and may mediate an increase of TERT and Bcl-2 levels but not of IL-18. Further study is required to elucidate the mechanism of the protective effect of montelukast on HIBD.

Topics: Acetates; Animals; Animals, Newborn; Case-Control Studies; Cyclopropanes; Disease Models, Animal; Hypoxia-Ischemia, Brain; Immunohistochemistry; Interleukin-18; Proto-Oncogene Proteins c-bcl-2; Quinolines; Rats; Sulfides; Telomerase

To determine the efficacy of montelukast in comparison with cabergoline in the prevention of ovarian hyperstimulation syndrome (OHSS) in rats.. An experimental OHSS model was formed in 35 female Wistar rats. Rats (22 days old) were randomized into 5 groups, each containing 7 animals. The control group received no therapy; the mild OHSS group was administered pregnant mare serum gonadotropin (PMSG) 10 IU for 4 days, hCG 10 IU on the 5th day; the severe OHSS group received PMSG 10 IU for 4 days, hCG 30 IU on the 5th day The montelukast group: received montelukast 10 mg/kg/day and the cabergoline group was administered cabergollne 100 microg/kg/day via oral gavage for 6 days (days 22-27), in addition to those of severe OHSS. All groups were sacrificed on 28th day Body weight, ovarian diameter and weight, vascular permeability vascular endothelial growth factor (VEGF), semiquantitative VEGF receptor-1, and VEGF receptor-2 (VEGFR-2) immunohistochemistry were evaluated.. Ovarian diameter and VEGF expression were significantly lower in the montelukast and cabergoline groups than in the severe OHSS group. While montelukast was more effective in limiting vascular permeability in the severe OHSS, cabergoline was superior to montelukast with respect to the limiting effect on increased body weight and VEGFR-2 expression.. The VEGF/VEGFR-2 interaction plays an important role in OHSS pathogenesis. Montelukast limits VEGF expression, and cabergoline reduces both VEGF and VEGFR-2 expressions; they are both effective therapies for the prevention of severe OHSS.

Topics: Acetates; Animals; Cabergoline; Chorionic Gonadotropin; Cyclopropanes; Disease Models, Animal; Dose-Response Relationship, Drug; Ergolines; Female; Ovarian Hyperstimulation Syndrome; Ovary; Quinolines; Random Allocation; Rats; Rats, Wistar; Sulfides

Cysteinyl leukotrienes (CysLTs) propagate inflammatory reactions that result from allergen exposure in asthma. Montelukast, a CysLT type-1 receptor antagonist, disrupts mediator-receptor interactions and minimizes inflammatory response. In this study, we have evaluated anti-asthmatic efficacy of inhalable montelukast-loaded large porous particulate formulations in ovalbumin-induced rat airway inflammation model that mimics asthma.. The anti-inflammatory effects of a montelukast-loaded formulation were investigated in rats by measuring the total protein content, levels of injury markers and number of inflammatory cells in the bronchoalveolar lavage fluid (BALF). The histopathological studies assessed the morphological and structural changes that occur in asthmatic lungs. Animals were also challenged with methacholine to examine the airway hyper-reactivity.. Compared with healthy animals, asthmatic animals showed a 3.8- and 4.77-fold increase in the protein content and number of inflammatory cells in BALF, respectively. Intratracheal montelukast particles reduced the protein content by 3.3-fold and the number of inflammatory cells by 2.62-fold. Also, montelukast particles reduced the lactate dehydrogenase (LDH) and myeloperoxidase (MPO) levels by a 4.87- and 6.8-fold in BALF, respectively. Montelukast particles reduced the airway wall thickness by 2.5-fold compared with untreated asthmatic lungs. Further, particulate formulation protected the lungs against methacholine-induced bronchial provocation (p < 0.05).. Respirable large porous particles containing montelukast alleviated allergen-induced inflammatory response in an animal model and prevented histological changes associated with asthma. Thus montelukast-loaded large porous polylactic acid (PLA) particles could be an aerosolized delivery approach for administration of currently available oral montelukast.

Topics: Acetates; Aerosols; Animals; Anti-Asthmatic Agents; Anti-Inflammatory Agents; Asthma; Bronchoalveolar Lavage Fluid; Cyclopropanes; Cysteine; Disease Models, Animal; Inflammation; L-Lactate Dehydrogenase; Lactic Acid; Leukotrienes; Lung; Ovalbumin; Peroxidase; Polyesters; Polymers; Quinolines; Rats; Rats, Sprague-Dawley; Sulfides

Noise-induced hearing loss is one of the most common types of sensorineural hearing loss. In this study, we examined the expression and localization of leukotriene receptors and their respective changes in the cochlea after hazardous noise exposure. We found that the expression of cysteinyl leukotriene type 1 receptor (CysLTR1) was increased until 3 d after noise exposure and enhanced CysLTR1 expression was mainly observed in the spiral ligament and the organ of Corti. Expression of 5-lipoxygenase was increased similar to that of CysLTR1, and there was an accompanying elevation of CysLT concentration. Posttreatment with leukotriene receptor antagonist (LTRA), montelukast, for 4 consecutive days after noise exposure significantly decreased the permanent threshold shift and also reduced the hair cell death in the cochlea. Using RNA-sequencing, we found that the expression of matrix metalloproteinase-3 (MMP-3) was up-regulated after noise exposure, and it was significantly inhibited by montelukast. Posttreatment with a MMP-3 inhibitor also protected the hair cells and reduced the permanent threshold shift. These findings suggest that acoustic injury up-regulated CysLT signaling in the cochlea and cochlear injury could be attenuated by LTRA through regulation of MMP-3 expression. This study provides mechanistic insights into the role of CysLTs signaling in noise-induced hearing loss and the therapeutic benefit of LTRA.

Topics: Acetates; Animals; Cochlea; Cyclopropanes; Cysteine; Disease Models, Animal; Gene Expression Profiling; Leukotriene Antagonists; Leukotrienes; Matrix Metalloproteinase 3; Mice; Noise; Quinolines; Receptors, Leukotriene; Signal Transduction; Sulfides; Wounds and Injuries

To evaluate the effects of montelukast and Hypericum perforatum against ischemia/reperfusion (I/R)-induced intestinal damage.. Twenty-eight hamsters were divided into 4 groups following midline abdominal laparotomy: control group (n = 7), I/R group (n = 7), montelukast and I/R (MIR) group (n = 7), and Hypericum perforatum and I/R (HPIR) group (n = 7). After 60 min of ischemia through obstruction of the superior mesenteric artery, 24 h of reperfusion was maintained. Ten minutes prior to the reperfusion period, the MIR group received 7 mg/kg of intraperitoneal montelukast and the HPIR group received 7 mg/kg of intraperitoneal Hypericum perforatum. Malondialdehyde, glutathione, myeloperoxidase, and cardiotrophin-1 levels were measured from blood samples. A semiquantitative histological evaluation was performed.. Montelukast and Hypericum perforatum significantly reduced malondialdehyde levels and increased glutathione levels compared to the I/R group (P < 0.008). A statistically significant difference was also found between the I/R group and MIR and HPIR groups in terms of myelqperoxidase levels (P < 0.008). The MIR and HPIR groups showed increased cardiotrophin- 1 levels compared to the control and I/R groups (P < 0.008 for all). The MIR and HPIR groups showed significantly lower histological scores compared to the I/R group (P = 0.03 and P = 0.007, respectively).. This study demonstrated the preventive effects of montelukast and Hypericum perforatum on I/R-induced intestinal injury.

Topics: Acetates; Animals; Cricetinae; Cyclopropanes; Disease Models, Animal; Glutathione; Hypericum; Intestines; Malondialdehyde; Mesenteric Artery, Superior; Mesocricetus; Plant Extracts; Protective Agents; Quinolines; Random Allocation; Reperfusion Injury; Sulfides

To compare the efficacy ofprednisolone, montelukast, and omalizumab in reducing allergic symptoms and inflammation at tissue level in an experimental allergic rhinitis model.. Forty Sprague Dawley rats were randomized into 5 groups as naive (NS/NC), sensitized/challenged (S/C) by subcutaneous ovalbumin antigen injection, and montelukast-, prednisolone-, and omalizumab-treated groups. A nasal allergen challenge was performed every day from day 20 to day 26. The number of sneezes and nasal/eye rubbing movements, IL-4 and CysLT levels in serum, nasal and bronchoalveolar lavage fluids determined by ELISA, and histopathological findings of nasal mucosa, sinus, and lung tissues were compared.. All of the treatments significantly controlled the allergic symptoms of sneezing and nasal/eye rubbing (P < 0.05). IL-4 and CysLT levels on days 20 and 26 were significantly higher in the S/C group compared to the NS/NC group (P < 0.05). Montelukast significantly decreased serum and nasal IL-4 and CysLT levels (P < 0.05), prednisolone decreased nasal lavage IL-4 and CysLT levels (P < 0.05), and omalizumab lowered nasal lavage CysLT levels (P < 0.05).. Prednisolone, montelukast, and omalizumab were found to be effective in controlling the allergic symptoms of allergic rhinitis and upper/lower airway inflammation in an experimental allergic rhinitis model.

Topics: Acetates; Animals; Anti-Allergic Agents; Antibodies, Anti-Idiotypic; Antibodies, Monoclonal, Humanized; Cyclopropanes; Disease Models, Animal; Lung; Mast Cells; Nasal Mucosa; Omalizumab; Prednisolone; Quinolines; Random Allocation; Rats; Rats, Sprague-Dawley; Rhinitis, Allergic; Sneezing; Sulfides

KOB03 is a polyherbal medicine derived from an oriental prescription traditionally used to treat allergic diseases. In the present study, we compared the efficacy of KOB03 with modern drugs such as ketotifen and montelukast in an experimental mouse model of allergic rhinitis (AR). Ketotifen is a H1 receptor antagonist and montelukast is a leukotriene receptor antagonist. Mice were treated with KOB03, ketotifen or montelukast in an established AR mouse model using ovalbumin (OVA)-sensitized/challenged BALB/c mice. The treatment of KOB03 had inhibitory effects on symptom scores, serum levels of OVA-specific IgE, histamine, leukotriene C4, IL-4, TNF-α, and IL-1β in AR mice, and the histolopathological changes of nasal mucosa with mucin release and inflammation. AR mice treated with KOB03 had significantly lower serum levels of OVA-specific IgE, LTC4, IL-4, and IL-1β than mice treated with ketotifen, whereas they only had significantly lower serum levels of OVA-specific IgE and IL-4 than those treated with montelukast. In addition, the histolopathological changes of nasal mucosa with eosinophil infiltration were significantly lower in the KOB03-treated mice than those in the ketotifen and montelukast-treated group. These results suggest that KOB03 has therapeutic potential for treating AR like other modern medicines.

Topics: Acetates; Animals; Anti-Allergic Agents; Antigens; Cyclopropanes; Cytokines; Disease Models, Animal; Histamine H1 Antagonists; Immunoglobulin E; Ketotifen; Leukotriene Antagonists; Leukotriene C4; Male; Mice; Mice, Inbred BALB C; Nasal Mucosa; Ovalbumin; Plant Extracts; Quinolines; Rhinitis, Allergic; Rhinitis, Allergic, Perennial; Sulfides

One feature of allergic asthma, the EAR (early allergic reaction), is not present in the commonly used mouse models. We therefore investigated the mediators involved in EAR in a guinea-pig in vivo model of allergic airway inflammation. Animals were sensitized using a single OVA (ovalbumin)/alum injection and challenged with aerosolized OVA on day 14. On day 15, airway resistance was assessed after challenge with OVA or MCh (methacholine) using the forced oscillation technique, and lung tissue was prepared for histology. The contribution of mast cell mediators was investigated using inhibitors of the main mast cell mediators [histamine (pyrilamine) and CysLTs (cysteinyl-leukotrienes) (montelukast) and prostanoids (indomethacin)]. OVA-sensitized and challenged animals demonstrated AHR (airway hyper-responsiveness) to MCh, and lung tissue eosinophilic inflammation. Antigen challenge induced a strong EAR in the sensitized animals. Treatment with a single compound, or indomethacin together with pyrilamine or montelukast, did not reduce the antigen-induced airway resistance. In contrast, dual treatment with pyrilamine together with montelukast, or triple inhibitor treatment, attenuated approximately 70% of the EAR. We conclude that, as in humans, the guinea-pig allergic inflammation model exhibits both EAR and AHR, supporting its suitability for in vivo identification of mast cell mediators that contribute to the development of asthma. Moreover, the known mast cell mediators histamine and leukotrienes were major contributors of the EAR. The data also lend further support to the concept that combination therapy with selective inhibitors of key mediators could improve asthma management.

Topics: Acetates; Animals; Asthma; Bronchial Hyperreactivity; Constriction, Pathologic; Cyclopropanes; Disease Models, Animal; Guinea Pigs; Histamine Antagonists; Hypersensitivity; Indomethacin; Leukotriene Antagonists; Lung; Mast Cells; Ovalbumin; Prostaglandin Antagonists; Pyrilamine; Quinolines; Sulfides

Foxa2 is a member of the Forkhead family of nuclear transcription factors that is highly expressed in respiratory epithelial cells of the developing and mature lung. Foxa2 is required for normal airway epithelial differentiation, and its deletion causes goblet-cell metaplasia and Th2-mediated pulmonary inflammation during postnatal development. Foxa2 expression is inhibited during aeroallergen sensitization and after stimulation with Th2 cytokines, when its loss is associated with goblet-cell metaplasia. Mechanisms by which Foxa2 controls airway epithelial differentiation and Th2 immunity are incompletely known. During the first 2 weeks after birth, the loss of Foxa2 increases the production of leukotrienes (LTs) and Th2 cytokines in the lungs of Foxa2 gene-targeted mice. Foxa2 expression inhibited 15-lipoxygenase (Alox15) and increased Alox5 transcription, each encoding key lipoxygenases associated with asthma. The inhibition of the cysteinyl LT (CysLT) signaling pathway by montelukast inhibited IL-4, IL-5, eotaxin-2, and regulated upon activation normal T cell expressed and presumably secreted expression in the developing lungs of Foxa2 gene-targeted mice. Montelukast inhibited the expression of genes regulating mucus metaplasia, including Spdef, Muc5ac, Foxa3, and Arg2. Foxa2 plays a cell-autonomous role in the respiratory epithelium, and is required for the suppression of Th2 immunity and mucus metaplasia in the developing lung in a process determined in part by its regulation of the CysLT pathway.

Topics: Acetates; Animals; Arachidonate 12-Lipoxygenase; Arachidonate 15-Lipoxygenase; Arachidonate 5-Lipoxygenase; Cyclopropanes; Cysteine; Disease Models, Animal; Eosinophils; Goblet Cells; Hepatocyte Nuclear Factor 3-beta; Inflammation Mediators; Leukotriene Antagonists; Leukotrienes; Metaplasia; Mice; Mice, Knockout; Mice, Transgenic; Pneumonia; Quinolines; Signal Transduction; Sulfides; Th2 Cells

The effects of anti-ulcerogenic drugs are dependent on the increase in prostaglandin production and reduction in leukotriene production in the gastric mucosa. Montelukast is an anti-asthmatic drug, a selective reversible cysteinyl leukotriene D4 receptor antagonist. In this study, we aimed to evaluate the anti-ulcerogenic effect of montelukast and to investigate the relationship between its anti-ulcerogenic effect and polymorphonuclear leukocyte infiltration in the gastric tissues.. Male Sprague-Dawley rats were separated into five groups. Distilled water (control group), famotidine (40 mg/kg), and montelukast (5, 10 and 20 mg/kg) were given orally (gavage). Thirty minutes later, indomethacin (25 mg/kg) was administered to all the groups. Six hours later, the animals were sacrificed by decapitation. The ulcer indexes for each stomach and the ulcer inhibition rates for each group were calculated, and the stomachs were later evaluated histopathologically (polymorphonuclear leukocyte infiltration).. Ulcer inhibition rates were as follows: famotidine 96.14% and montelukast 59.96%, 72.65% and 76.97% (5, 10 and 20 mg/kg, respectively). Montelukast (10 and 20 mg/kg) showed effects similar to those of famotidine histopathologically.. In this study, it was observed that there was a relationship between the anti-ulcerogenic effect of montelukast and polymorphonuclear leukocyte infiltration in the gastric mucosa, and montelukast behaved as an anti-ulcerogenic drug both macroscopically and microscopically.

Topics: Acetates; Animals; Anti-Ulcer Agents; Cyclopropanes; Disease Models, Animal; Famotidine; Gastric Mucosa; Indomethacin; Leukocyte Count; Leukotriene Antagonists; Male; Neutrophils; Quinolines; Rats; Rats, Sprague-Dawley; Stomach Ulcer; Sulfides

Bronchiolar Clara cells play a critical role in lung homoeostasis. The main goal of this study was to evaluate the effects of chronic allergy on these cells and the efficacy of budesonide (BUD) and montelukast (MK) in restoring their typical phenotypes after ovalbumin-induced chronic allergy in mice. Chronic allergy induced extensive bronchiolar Alcian blue-periodic acid-Schiff (AB/PAS)-positive metaplasia. In addition, cells accumulated numerous big electron-lucent granules negative for Clara cell main secretory protein (CC16), and consequently, CC16 was significantly reduced in bronchoalveolar lavage. A concomitant reduction in SP-D and CYP2E1 content was observed. The phenotypic changes induced by allergy were pharmacologically reversed by both treatments; MK was more efficient than BUD in doing so. MK decreased AB/PAS reactivity to control levels whereas they remained persistently elevated after BUD. Moreover, most non-ciliated cells recovered their normal morphology after MK, whereas for BUD normal cells coexisted with 'transitional' cells that contained remnant mucous granules and stained strongly for CC16 and SP-D. Glucocorticoids were also less able to reduce inflammatory infiltration and maintained higher percentage of neutrophils, which may have contributed to prolonged mucin expression. These results show that chronic allergy-induced mucous metaplasia of Clara cells affects their defensive mechanisms. However, anti-inflammatory treatments were able to re-establish the normal phenotype of Clara cell, with MK being more efficient at restoring a normal profile than BUD. This study highlights the role of epithelial cells in lung injuries and their contribution to anti-inflammatory therapies.

Topics: Acetates; Animals; Anti-Asthmatic Agents; Anti-Inflammatory Agents; Asthma; Bronchi; Budesonide; Chronic Disease; Cyclopropanes; Cytochrome P-450 CYP2E1; Disease Models, Animal; Epithelium; Female; Mice; Mice, Inbred BALB C; Ovalbumin; Phenotype; Pulmonary Surfactant-Associated Protein D; Quinolines; Sulfides; Uteroglobin

Leukotrienes are the major factors in the formation of edema and mucus, as well as development of tuba Eustachii dysfunction in acute otitis media. We developed an experimental acute suppurative otitis media model and compared the responses of rats to penicillin and combinations of leukotriene antagonist with respect to histopathological observations conducted in early and late phases.. A total of 83 ears from 56 Wistar rats were used in this study. Pneumococcus suspension was injected trans-tympanically into all rats. Subjects were classified into 4 different groups with 14 rats in each. In Group A, intramuscular penicillin G was injected for a period of 5 days. In Group B, intraperitoneal montelukast was injected for 21 days in addition to penicillin. In Group C, intraperitoneal montelukast isotonic NaCl in Group D was injected into rats for 21 days.. No significant difference was found between the groups, except for mucosal vascularization with respect to mucosal and TM parameters in early phases. Furthermore, considerable deviations were observed for the recuperation of TM and mucosal inflammation for groups in which subjects were injected with montelukast as compared to other groups of the study in the late phases.. When the parameters of inflammation in the rat middle ear were compared with each other, most of these parameters did not show any statistically significant beneficial effects in montelukast and penicillin groups.

Topics: Acetates; Animals; Cyclopropanes; Disease Models, Animal; Ear, Middle; Female; Mucous Membrane; Otitis Media; Penicillins; Quinolines; Rats; Rats, Wistar; Sulfides

Montelukast, a leukotriene receptor antagonist, is used commercially as a maintenance treatment for asthma and to relieve allergic symptoms. In this study, we evaluated the protective effects of montelukast against the airway inflammation and fibrosis using a murine model of ovalbumin (OVA) induced chronic asthma. The animals received OVA challenge three times a week for 4 weeks. Montelukast (30 mg/kg) was administrated orally once a day for 4 weeks. The administration of montelukast caused a reduction in elevated interleukin (IL)-4, IL-13, eotaxin, immunoglobulin (Ig), inflammatory cell infiltration into the airways, and mucus production after repeated OVA challenges. To investigate the antifibrotic mechanism of montelukast, we examined the expression of profibrotic mediators, including vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-β1, and Smad3 proteins in the lung tissue using western blotting and immunohistochemistry. The administration of montelukast reduced the overexpression of profibrotic proteins in the lung tissue, which was confirmed by immnunohistochemistry. These results are consistent with a histopathological examination of lung tissue with Masson's trichrome stain. In conclusion, the administration of montelukast reduced airway inflammation and pulmonary fibrosis by reducing the release of Th2 cytokines and the expression of VEGF, TGF-β1/Smad3 in the lung tissue.

Topics: Acetates; Allergens; Animals; Anti-Asthmatic Agents; Asthma; Bronchoalveolar Lavage Fluid; Cyclopropanes; Cytokines; Disease Models, Animal; Female; Immunoglobulin E; Leukotriene Antagonists; Lung; Mice; Mice, Inbred BALB C; Mucus; Ovalbumin; Pulmonary Fibrosis; Quinolines; Smad3 Protein; Sulfides; Transforming Growth Factor beta1; Vascular Endothelial Growth Factor A

Compare the effects of montelukast or dexamethasone in distal lung parenchyma and airway walls of guinea pigs (GP) with chronic allergic inflammation.. GP have inhaled ovalbumin (OVA group-2x/week/4weeks). After the 4th inhalation, GP were treated with montelukast or dexamethasone. After 72 hours of the 7th inhalation, GP were anesthetised, and lungs were removed and submitted to histopathological evaluation.. Montelukast and dexamethasone treatments reduced the number of eosinophils in airway wall and distal lung parenchyma compared to OVA group (P < 0.05). On distal parenchyma, both treatments were effective in reducing RANTES, NF- κ B, and fibronectin positive cells compared to OVA group (P < 0.001). Montelukast was more effective in reducing eotaxin positive cells on distal parenchyma compared to dexamethasone treatment (P < 0.001), while there was a more expressive reduction of IGF-I positive cells in OVA-D group (P < 0.001). On airway walls, montelukast and dexamethasone were effective in reducing IGF-I, RANTES, and fibronectin positive cells compared to OVA group (P < 0.05). Dexamethasone was more effective in reducing the number of eotaxin and NF- κ B positive cells than Montelukast (P < 0.05).. In this animal model, both treatments were effective in modulating allergic inflammation and remodeling distal lung parenchyma and airway wall, contributing to a better control of the inflammatory response.

Topics: Acetates; Administration, Inhalation; Animals; Chronic Disease; Cyclopropanes; Dexamethasone; Disease Models, Animal; Guinea Pigs; Hypersensitivity; Inflammation; Leukotriene Antagonists; Lung; Ovalbumin; Quinolines; Sulfides

This study examined the effect of montelukast and beclomethasone on airway remodeling in murine model of asthma. Mice were sensitized by i.p. injection of ovalbumin (OVA) on days 0 and 14, and then challenged by nebulization of 1% OVA 3 days/week for 6 or 10 weeks. Results of 6-week OVA-challenged group showed moderate inflammation, but the 10-week OVA-challenged group exhibited mild inflammation. The OVA challenge (6 and 10 weeks) exhibited marked airway fibrosis, illustrated by significant increase in goblet cell hyperplasia and epithelial thickness, increased lung content of collagen and transforming growth factor-β(1), together with a decrease in nitric oxide production; also, there was an increase in bronchoalveolar lavage fluid level of interleukin-13. Administration of montelukast or beclomethasone before each OVA challenge was capable of restoring most of the measured parameters to near normal levels. Inhalation of beclomethasone has a similar role in airway remodeling as montelukast, but its effects in regulating inflammatory changes is less pronounced than montelukast.

Topics: Acetates; Administration, Inhalation; Airway Remodeling; Animals; Anti-Asthmatic Agents; Asthma; Beclomethasone; Cyclopropanes; Disease Models, Animal; Inflammation; Male; Mice; Ovalbumin; Quinolines; Severity of Illness Index; Sulfides; Time Factors

We evaluated the effects of anti-iNOS (1400W - W) associated with leukotriene antagonist (montelukast - M) or corticosteroid (dexamethasone - D) on distal lung of guinea pigs (GP) with chronic pulmonary inflammation.. GP were inhaled with ovalbumin (OVA-2×/week/4 weeks), treated with M (OVAM), D (OVAD) and/or W (OVAW, OVADW, OVAMW) and distal lungs were evaluated by morphometry.. Isolated treatments were not sufficient to reduce all parameters. In OVADW, all parameters were reduced with greater reduction in elastic fibers, TIMP-1, IL-4, IL-5, IFN-gamma and PGF2-alpha compared with OVAD (p<0.05). OVAMW potentiated the reduction of actin, elastic fibers, TIMP-1, IL-4, IL-5, TGF-beta, IFN-gamma, iNOS, and PGF2-alpha to a greater extent than OVAM (p<0.05). A reduction of TIMP-1, IL-4, IL-5, TGF-beta, IFN-gamma and iNOS was observed in OVADW compared with OVAMW (p<0.05).. Although anti-iNOS paired with montelukast or dexamethasone yields better results than isolated treatments, the most effective pairing for controlling inflammation, oxidative stress and remodeling in this asthma model was found to be corticosteroids and anti-iNOS.

Topics: Acetates; Amidines; Animals; Anti-Inflammatory Agents; Benzylamines; Chronic Disease; Cyclopropanes; Cytokines; Dexamethasone; Disease Models, Animal; Enzyme Inhibitors; Eosinophils; Guinea Pigs; Lung; Male; Ovalbumin; Pneumonia; Quinolines; Statistics, Nonparametric; Sulfides

In this study, the therapeutic and protective effects of montelukast against cisplatin (CP)-induced acute renal damage were investigated.. Thirty-five female rats were divided into five groups as follows: (1) control, (2) montelukast (10 mg/kg daily for 10 days per-oral (p.o.), (3) CP (single dose 7 mg/kg intraperitoneally (i.p.)), (4) CP + montelukast (10 mg/kg daily for 10 days p.o., after 3 days of the injection of CP), (5) montelukast (10 mg/kg daily for 10 days p.o.) + CP (single dose 7 mg/kg i.p., after the last dose of montelukast). At the end of the experiment, malondialdehyde (MDA), a lipid peroxidation product, myeloperoxidase (MPO), and reduced glutathione (GSH) levels were determined in the renal tissue. Also, blood urea nitrogen (BUN) and creatinine (Cr) levels were assayed from the trunk blood samples.. CP treatment caused a significant elevation of MDA, MPO, BUN, and Cr levels when compared with the control group. Also, GSH levels were found to be reduced due to the CP treatment. Montelukast administration after CP injection ameliorated all of these parameters. Our histopathological findings (marked swelling of epithelial cells, tubular dilatation, tubular desquamation, and loss of brush border in the kidney) were consistent with the biochemical results.. Montelukast treatment after CP injection exerted therapeutic effects against CP-induced acute kidney damage.

Topics: Acetates; Acute Kidney Injury; Animals; Blood Urea Nitrogen; Cisplatin; Creatinine; Cyclopropanes; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Glutathione; Injections, Intraperitoneal; Kidney; Leukotriene Antagonists; Malondialdehyde; Oxidative Stress; Peroxidase; Quinolines; Rats; Rats, Wistar; Spectrophotometry; Sulfides; Treatment Outcome

The therapeutic and protective effects of montelukast against amikacin-induced acute renal damage were investigated.. 35 Wistar albino female rats were divided into 5 groups as follows: Group I: Control; Group II: Control+montelukast; Group III: Amikacin; Group IV: Amikacin+montelukast; Group V: Montelukast+amikacin. At the end of the experiment, the kidney tissues and the blood of rats were collected. Malondialdehyde (MDA), myeloperoxidase (MPO), and reduced glutathione (GSH) levels were determined from kidney tissues. Blood urea nitrogen (BUN), creatinine (Cr), TNF-alpha, and IL-1beta levels were assessed in the serum. In addition the kidney tissues were examined histologically.. The MDA, MPO, BUN, and Cr levels of group III significantly increased when compared to groups I and II. These parameters of group IV decreased when compared to group III. In addition, GSH levels significantly increased when compared to the first three groups. MDA, BUN and Cr levels of group V did not reach significant level in comparison with the control group. The most significant histological damage was observed in the group III followed by the groups IV and V. Immunohistochemically, group III showed a significantly increased apoptotic staining. In group IV, it was observed that montelukast treatment reduced the expression of apoptotic cells.. Montelukast treatment after amikacin injection could reduce the amikacin-induced kidney damage.

Topics: Acetates; Acute Disease; Amikacin; Animals; Anti-Inflammatory Agents; Antioxidants; Apoptosis; Blood Urea Nitrogen; Creatinine; Cyclopropanes; Cytoprotection; Disease Models, Animal; Female; Glutathione; Immunohistochemistry; Interleukin-1beta; Kidney; Kidney Diseases; Malondialdehyde; Peroxidase; Quinolines; Rats; Rats, Wistar; Sulfides; Tumor Necrosis Factor-alpha

To determine whether MUC gene expression could be down-regulated in nasal polyps by the leukotriene receptor antagonist montelukast, we developed a system in which nondisrupted human nasal polyps could be successfully implanted into severely immunocompromised mice, and in which the histopathology of the original nasal polyp tissue could be preserved for long periods. In addition, the histopathologic changes in the human nasal polyps were carefully examined to determine the origin of the submucosal glands (SMGs) that develop in true nasal polyps found in the anterior third of the nose.. Small, nondisrupted pieces of human nasal polyp tissues were subcutaneously implanted into NOD-scid IL-2rgamma(null) mice. Xenograft-bearing mice were treated with either montelukast or saline solution. Xenografts at 8 to 12 weeks after implantation were examined histologically, and expression of MUC genes 4, 5AC, and 7 was studied in the polyps before implantation and in the 8-week xenograft. Alzet pumps were inserted into the mice, and montelukast (Singulair) was continuously delivered to determine its effect on goblet cell hyperplasia, mucus production, and the enlargement of nasal polyps over an 8-week period.. The xenografts were maintained in a viable and functional state for up to 3 months and retained a histopathology similar to that of the original tissue, but with a noticeable increase in goblet cell hyperplasia and marked mucus accumulation in the SMGs. MUC4 and MUC5AC were significantly increased in the xenograft 8 weeks after implantation, but MUC7 was significantly decreased compared to the preimplantation polyps. Inasmuch as MUC7 is found exclusively in serous glands, the findings suggest that serous glands are not found in polyps in the anterior third of the nose. The histopathologic findings confirm the original findings of Tos et al suggesting that the SMGs are derived from pinching-off of the epithelium of the enlarging polyp following inflammatory changes. These SMGs have the same epithelium as surface epithelium and consist of multiple goblet cells that secrete periodic acid Schiff stain-positive mucin into the interior of the SMGs. A progressive increase in the volume of the xenografts was observed, with little or no evidence of mouse cell infiltration into the human leukocyte antigen-positive human tissue. An average twofold increase in polyp volume was found 2 months after engraftment. Montelukast did not decrease the growth of the xenograft in the 8-week NOD-scid mice, nor did it affect MUC gene expression.. The use of innate and adaptive immunodeficient NOD-scid mice homozygous for targeted mutations in the IL-2 gamma-chain locus NOD-scid IL-2r gamma(null) for establishing engraftment of nondisrupted pieces of human nasal polyp tissues represents a significant advancement in studying chronic inflammation over a long period of time. In the present study, we utilized this humanized mouse model to confirm our prediction that MUC genes 4 and 5AC are highly expressed and significantly increased over those of preimplanted polyps. The overexpression of these 2 MUC genes correlates with both the goblet cell hyperplasia and the excessive mucus production that are found in nasal polyp xenografts. MUC7, which is primarily associated with the submucosa, as opposed to MUC4 and MUC5AC, which are primarily expressed in the epithelium, was significantly decreased in the nasal polyp xenografts. Montelukast had no significant effect on MUC gene expression in the xenografts. In addition to the MUC gene expression patterns, the histology of the xenografts supports the concept that mucinous glands that are characteristic of true nasal polyps are significantly different from those in the mucosa found in the lateral wall of the nose in patients with chronic sinusitis without nasal polyps. The mucinous glands seen in nasal polyps (which appear to be derived from an invagination of hyperplastic epithelial mucosa containing large numbers of goblet cells) are histologically distinct from the seromucinous glands found in the submucosa of hyperplastic middle turbinates. The data presented here establish a humanized mouse model as a viable approach to study nasal polyp growth, to assess the therapeutic efficacy of various drugs in this chronic inflammatory disease, and to contribute to our understanding of the pathogenesis of this disease.

Topics: Acetates; Animals; Anti-Inflammatory Agents; Biomarkers, Tumor; Cyclopropanes; Disease Models, Animal; Gene Expression Regulation; Goblet Cells; Humans; Mice; Mice, SCID; Mucin 5AC; Mucin-4; Mucins; Nasal Mucosa; Nasal Polyps; Quinolines; Salivary Proteins and Peptides; Sulfides

We demonstrated previously that GATA-3 overexpression markedly enhanced allergen-induced airway inflammation and airway remodelling, including subepithelial fibrosis, and smooth muscle cell hyperplasia, in transgenic mice.. Because cysteinyl leukotrienes (cysLTs) have been shown to be involved in such structural changes, the effects of a specific cysLT1 receptor antagonist, montelukast, were evaluated in a mouse model of chronic asthma.. GATA-3-overexpressing mice and wild-type Balb/c mice were sensitized and repeatedly challenged by ovalbumin (OVA) or saline. The effects of montelukast on the development of airway remodelling were compared between the two mouse genotypes.. CysLTs in the lung were increased after repeated allergen challenges, and significantly enhanced in GATA-3-overexpressing mice. The enhanced cysLT levels were accompanied by the development of eosinophilia, smooth muscle cell hyperplasia, and increased stromal cell-derived factor-1 gene expression with a small increase in pro-collagen gene expression in OVA-challenged GATA-3-overexpressing mice, but not in wild-type mice. Montelukast significantly decreased lung cysLT levels and inhibited the GATA-3-overexpression-related airway remodelling, potently preventing smooth muscle cell hyperplasia, but partially suppressed the increased pro-collagen gene expression and eosinophilic inflammation. Increases in the levels of IL-4, IL-5, IL-13, and eotaxin in bronchial lavage and TGF-β gene expression in the lungs were induced by OVA in both mouse genotypes. Montelukast treatment also significantly reduced these levels to the levels seen after saline challenges in GATA-3-overexpressing mice.. Montelukast efficaciously prevented airway inflammation and remodelling in a GATA-3-overexpression antigen challenge mouse model by decreasing the cysLT-driven Th2 cytokine cycle of amplification of airway pathologies.

Topics: Acetates; Airway Remodeling; Animals; Cyclopropanes; Disease Models, Animal; GATA3 Transcription Factor; Mice; Mice, Inbred BALB C; Mice, Transgenic; Quinolines; Receptors, Leukotriene; Reverse Transcriptase Polymerase Chain Reaction; Sulfides; Th2 Cells

What's known on the subject? and What does the study add? The mastocytosis in detrusor muscle and the leaky epithelium in interstitial cystitis were the most studied features. In this study the leaky epithelium was shown using the ruthenium red staining in electron microscopy and uroplakin distribution in light microscopy besides the mast cell concentration in detrusor muscle using tryptase immunohistochemistry.. • To study the effects of montelukast (ML), a leukotriene receptor antagonist which has been shown to be effective in inhibiting the action of cysteinyl-containing leukotrienes, on protamine sulphate (PS)-induced changes in rat urinary bladder.. • Wistar female rats were catheterized and intravesically infused with PBS (control group) or PS (PS group) dissolved in PBS twice in 24 h. • In the PS-applied and ML-treated group (PS + ML group) after the 10 mg/kg PS instillation, ML was injected i.p. twice daily for 3 days. • The urinary bladder was investigated for general morphology under a light microscope. • Tryptase immunohistochemistry was used to observe mast cell distribution and activation. Uroplakin distribution was also identified with immunohistochemistry.. • Alterations of glycosaminoglycan (GAG) and urothelial permeability were seen with ruthenium red (RR) staining techniques under a transmission electron microscope, and topographical changes of luminal urothelial structure were seen with a scanning electron microscope. • Biochemically malondialdehyde (MDA) and gluthatione (GSH) concentrations were analysed. In the PS group, there was degenerated urothelium with irregular uroplakin distribution, increased inflammatory cell infiltration, increased number of both granulated and activated mast cells, irregularity of GAG and penetration of RR into the intercellular spaces and dilated tight junctions. • In PS + ML group, there was relatively regular uroplakin distribution, a decrease in inflammatory cell infiltration, a decreased number of both activated and granulated mast cells in the mucosa, regular GAG and no penetration of RR into the intercellular areas, and regular tight junctions in most regions. • The significant decrease in MDA and the increased GSH concentrations in the PS + ML group was in accordance with the histological findings.. • Montelukast appears to have a protective function in the bladder injury model via the anti-inflammatory effects of this leukotriene receptor antagonist.

Topics: Acetates; Animals; Cell Count; Cyclopropanes; Cystitis, Interstitial; Disease Models, Animal; Female; Glutathione; Glycosaminoglycans; Immunohistochemistry; Leukotriene Antagonists; Malondialdehyde; Mast Cells; Microscopy, Electron, Transmission; Protamines; Quinolines; Rats; Rats, Wistar; Sulfides; Tryptases; Urinary Bladder; Urothelium

The present study aimed to investigate the effects of indomethacine, montelukast and methylprednisolone in management of experimental otitis media with effusion.. Forty Wistar albino rats of which the weights ranged between 310 and 370 g were included in this study. Middle ear effusion was created by transtympanic histamine injection. The presence of effusion was confirmed by otomicroscopic examination. Thirty-seven rats with effusion were divided into 4 groups (methylprednisolone, montelukast, indomethacine and saline-control groups). All agents were administered for a period of consecutive 10 days. At the 11th days of administration, the recovery of effusion was confirmed by otomicroscopic examination. Tympanic bullae of the rats were removed and histopathological examinations were carried out. In the histopathological examination, the neutrophil leukocytes accumulated in the middle ear submucosa were counted.. The mean numbers of submucosal neutrophils in the methylprednisolone, montelukast, indomethacine, and saline groups were 24.6±8.1, 54.1±6.2, 52.3±7.3, 55.7±8.3, respectively. The otomicroscopic recovery rates of effusion in the methylprednisolone, montelukast, indomethacine, and saline groups were 18/18 (100%), 8/18 (44%), 2/14 (14%), 2/18 (11%) respectively.. Methylprednisolone and montelukast ameliorate the middle ear effusion. However, only methylprednisolone reduces the submucosal infiltration of the neutrophil leukocytes which are the most evident cell of inflammatory process. Montelukast is effective in the resolution of experimental otitis media with effusion.

Topics: Acetates; Administration, Oral; Animals; Biopsy, Needle; Cyclopropanes; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Immunohistochemistry; Indomethacin; Injections, Intraperitoneal; Male; Methylprednisolone; Otitis Media with Effusion; Otoscopy; Quinolines; Random Allocation; Rats; Rats, Wistar; Reference Values; Statistics, Nonparametric; Sulfides; Treatment Outcome

Previously we demonstrated the neuroprotective effect of montelukast, a cysteinyl leukotriene receptor-1 (CysLT(1) ) antagonist, on acute brain injury after focal cerebral ischaemia in mice. In this study, we have determined its effect on chronic brain injury after focal cerebral ischaemia in mice and rats.. After transient focal cerebral ischaemia was induced by middle cerebral artery occlusion, montelukast was intraperitoneally injected in mice or orally administered to rats for five days. Behavioural dysfunction, brain infarct volume, brain atrophy and neuron loss were determined to evaluate brain lesions.. Montelukast (0.1 mg/kg) attenuated behavioural dysfunction, brain infarct volume, brain atrophy and neuron loss in mice, which was similar to pranlukast, another CysLT(1) receptor antagonist. Oral montelukast (0.5 mg/kg) was effective in rats and was more effective than edaravone, a free radical scavenger.. Montelukast protected mice and rats against chronic brain injury after focal cerebral ischaemia, supporting the therapeutic potential of CysLT(1) receptor antagonists.

Topics: Acetates; Administration, Oral; Animals; Antipyrine; Atrophy; Behavior, Animal; Brain Injury, Chronic; Chromones; Cyclopropanes; Disease Models, Animal; Drug Evaluation, Preclinical; Edaravone; Free Radical Scavengers; Infarction, Middle Cerebral Artery; Injections, Intraperitoneal; Leukotriene Antagonists; Male; Mice; Mice, Inbred ICR; Nerve Degeneration; Quinolines; Rats; Rats, Sprague-Dawley; Sulfides

Non-steroidal anti-inflammatory drugs (NSAIDS) are the first line of therapy in acute gouty arthritis. NSAIDs inhibit the cyclooxygenase pathway, but not the lipooxygenase activity and can have many adverse effects and thus have a limited effect on the control of inflammation in this disease. In this work we studied the effect of montelukast on the cellular inflammatory infiltrate in a model of murine arthritis induced by sodium monourate crystals (SMU), using a subcutaneous air cavity (air pouch) in BALB/c mice. Seven groups of BALB/c mice (n = 4) were distributed into five experimental groups and two inflammatory control groups, a positive and a negative one. Previous to SMU exposure, the experimental groups received montelukast (1 and 0.01 mg/Kg/w) and/or indomethacine (2.5 mg/Kg/w), followed by administration of SMU in the air pouch. The total and differential counts of inflammatory cells were analyzed after 2, 6, 12 and 24 hours. Montelukast, significantly reduced the total number of cells (p < 0.05), with a predominant impact on polymorphonuclear over mononuclear cells, especially after 12 hours of the medication. The montelukast/indometacine combination showed an additive effect. Our data show that montelukast has an anti-inflammatory effect in the model of gouty arthritis. Consequently, anti-leukotrienes could represent a new and effective therapy, either isolated or combined with conventional therapy of gouty arthritis.

Topics: Acetates; Animals; Anti-Inflammatory Agents, Non-Steroidal; Arthritis, Gouty; Cell Migration Assays, Leukocyte; Cyclopropanes; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Drug Synergism; Indomethacin; Inflammation; Leukocytes, Mononuclear; Leukotriene Antagonists; Male; Mice; Mice, Inbred BALB C; Neutrophils; Premedication; Quinolines; Sulfides; Uric Acid

We investigated the potential protective effects of montelukast (MLK) on cecal ligation and puncture (CLP)-induced tissue injury in vital organs - liver, heart, kidneys, and especially lungs - through inhibition of the proinflammatory cytokine response and the generation of reactive oxygen species (ROS) in rats. The rat groups were (1) a 10-mg/kg MLK-treated CLP group; (2) a 20-mg/kg MLK-treated CLP group; (3) a 20-mg/kg MLK-treated, sham-operated group; (4) a CLP control group; and (5) a sham-operated control group. MLK treatment significantly decreased proinflammatory (tumor necrosis factor-alpha, interleukin-6) cytokine levels following CLP. The lipid peroxide level increased in the lung, heart, liver, and kidney tissues after CLP-induced sepsis, and myeloperoxidase activity increased in the lung, heart, and liver tissues. MLK attenuated this elevation in all tissues except the kidney, dose dependently. The glutathione levels and superoxide dismutase activity were significantly increased in the lung, liver, and kidney tissues after MLK treatment. MLK treatment after CLP also potentially reduced mortality. The lung and kidney tissues were the most protected by MLK under sepsis conditions. We can suggest that MLK reverses the systemic inflammatory reaction to polymicrobial sepsis and thereby reduces multiple organ failure.

Topics: Acetates; Animals; Cecum; Cyclopropanes; Cytokines; Disease Models, Animal; Glutathione; Heart; Kidney; Lipid Peroxides; Liver; Lung; Multiple Organ Failure; Myocardium; Peroxidase; Protective Agents; Quinolines; Rats; Reactive Oxygen Species; Sepsis; Sulfides; Superoxide Dismutase

In the present study, we tried to explore the mechanism of montelukast as an antiulcerogenic agent in pyloric ligation (PL) and water immersion stress (WIS) induced peptic ulcer. The ameliorative effects of montelukast (5, 10, and 20 mg/kg, p.o.) on gastric volume and total acidity were studied in PL model. We have investigated the alteration in the ulcerative index, thiobarbituric acid reactive substances, reduced glutathione, activity of myeloperoxidase, and total calcium level in both models. Estimation of DNA fragmentation by gel electrophoresis was also performed. Medium and higher doses of montelukast showed significant (p<0.05) ameliorative potential on all the above parameters as compared with omeprazole treated group. DNA fragmentation pattern clearly indicated the antiapoptotic effect of montelukast in preventing mucosal erosion in both models. Hence, the gastroprotective effect of montelukast may be attributed to its antisecretory, antioxidative along with its antiapoptotic effect.

Topics: Acetates; Animals; Cyclopropanes; Disease Models, Animal; DNA Fragmentation; Gastric Mucosa; Glutathione; Leukotriene Antagonists; Male; Peptic Ulcer; Peroxidase; Quinolines; Rats; Rats, Wistar; Stomach; Stress, Psychological; Sulfides; Thiobarbituric Acid Reactive Substances

Respiratory syncytial virus (RSV) bronchiolitis in infants may be followed by the development of asthma-like symptoms. Age at first infection dictates consequences upon reinfection. Reinfection of mice initially exposed as neonates to RSV enhanced development of airway hyperresponsiveness (AHR), eosinophilic inflammation, and mucus hyperproduction. RSV lower respiratory tract disease is associated with activation of the leukotriene pathway.. To determine the effects of montelukast (MK), a cysteinyl leukotriene (cysLT) receptor antagonist, in primary and secondary RSV-infected newborn and adult mice.. BALB/c mice were infected with RSV at 1 week (neonate) or 6 to 8 weeks (adult) of age and reinfected 5 weeks later. MK was administered 1 day before the initial infection and through Day 6 after infection. Seven days after primary or secondary infection, airway function was assessed by lung resistance to increasing doses of inhaled methacholine; lung inflammation, goblet cell metaplasia, and cytokine levels in bronchoalveolar lavage fluid were monitored.. RSV infection induced cysLT release in bronchoalveolar lavage fluid. MK decreased RSV-induced AHR, airway inflammation, and increased IFN-gamma production in primary infected adult and neonatal mice. MK, administered during initial infection of neonates but not during secondary infection, prevented subsequent enhancement of AHR, airway eosinophilia, and mucus hyperproduction upon reinfection.. MK attenuated the initial responses to primary RSV infection in both age groups and altered the consequences of RSV reinfection in mice initially infected as neonates. These data support an important role for cysLT in RSV-induced AHR and inflammation.

Topics: Acetates; Animals; Animals, Newborn; Anti-Asthmatic Agents; Bronchiolitis, Viral; Bronchoalveolar Lavage Fluid; Cyclopropanes; Cysteine; Disease Models, Animal; Inflammation; Interferon-gamma; Leukotriene Antagonists; Leukotrienes; Mice; Mice, Inbred BALB C; Quinolines; Recurrence; Respiratory Hypersensitivity; Respiratory Syncytial Virus Infections; Respiratory Syncytial Viruses; Sulfides

The aim is to determine immunopathological modifications in rectal mucosa from rabbits after local challenge in ovalbumin (OVA) sensitized animals previously treated with montelukast.. thirty two rabbits divided into four groups: G1: normal; G2: subcutaneously OVA sensitized; G3: sensitized, locally OVA challenged and sampled 4 hours after challenge; and G4: sensitized, locally OVA challenged and treated 4 hours before challenge with montelukast (0.15 mg/kg). Specific anti-OVA IgE levels were evaluated by passive cutaneous anaphylaxis test (PCA). In each group 200 high microscopical power fields (HPF) were counted. Results were expressed as arithmetic mean and SE. Anti -CD4, CD5, micro chain monoclonal antibodies were used. Avidin biotin horseradish peroxidase system was used.. CD 4: G1: 8.3 +/- 0.06; G2: 13.4 +/- 0.08, G3: 8.25 +/- 0.06, G4: 11.8 +/- 0.02. CD 5: G1: 7.3 +/- 0.05; G2: 9.4 +/- 0.05, G3: 11.3 +/- 0.06, G4: 8.1 +/- 0.06. mu chain: G1: 10.4 +/- 0.06; G2: 3.8 +/- 0.02, G3: 6.0 +/- 0.10, G4: 2.2 +/- 0.10. In all cases, experimental groups (G3 vs. G4) presented statistical significant differences (p < 0.05). CD4+, CD5+ cells and mu chain+ decrease in experimental group (G4), probably due to lymphocyte migration inhibition to challenged mucosa. mu chain+ cell decrease could be based on B cell activation and expression of different surface immunoglobulins. Cells expressing mu chain decreased in G2 and G3 likely due to activation of B cells and subsequent expression of other immunoglobulin chains in cell surface.. We conclude that obtained data are important to elucidate immunopathology of local anaphylactic reaction in rectal mucosa from systemic sensitized animals after treatment with montelukast.

Topics: Acetates; Animals; Cyclopropanes; Disease Models, Animal; Food Hypersensitivity; Intestinal Mucosa; Leukotriene Antagonists; Quinolines; Rabbits; Sulfides

The authors aimed to investigate the effects of montelukast (ML) on the experimental rat colon anastomosis.. A total of 80 Wistar albino rats were divided into 4 groups: sham-operated, colon anastomosis, and colon anastomosis with oral administration (OAML) and rectal administration of 10 mg/kg/d ML (RAML). Anastomotic bursting pressure, anastomotic hydroxyproline contents, malondialdehyde (MDA), glutathione (GSH), glutathione peroxidase (GPX), and superoxide dismutase (SOD) levels, and the expressions of Ki-67, vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF) with immunohistochemistry were assessed on postoperative day 5.. Anastomotic bursting pressures and bFGF expressions were not changed, whereas tissue hydroxyproline concentrations and MDA levels and the expressions of Ki-67 and VEGF were significantly decreased, and GSH, GPX, and SOD levels were significantly increased in the OAML and RAML groups.. ML causes impairment of wound healing without altering the anastomosis bursting pressure and reverses the oxidative damage of the colon anastomoses in rats.

Topics: Acetates; Anastomosis, Surgical; Animals; Colon; Cyclopropanes; Disease Models, Animal; Leukotriene Antagonists; Oxidative Stress; Quinolines; Rats; Rats, Wistar; Sulfides; Treatment Outcome; Wound Healing

It has been well-documented that leukotrienes (LTs) are released in allergic lung inflammation and that they participate in the physiopathology of asthma. A role for LTs in innate immunity has recently emerged: Cys-LTs were shown to enhance FcgammaR-mediated phagocytosis by alveolar macrophages (AMs). Thus, using a rat model of asthma, we evaluated FcgammaR-mediated phagocytosis and killing of Klebsiella pneumoniae by AMs. The effect of treatment with a cys-LT antagonist (montelukast) on macrophage function was also investigated. Male Wistar rats were immunized twice with OVA/alumen intraperitoneally and challenged with OVA aerosol. After 24 h, the animals were killed, and the AMs were obtained by bronchoalveolar lavage. Macrophages were cultured with IgG-opsonized red blood cells (50:1) or IgG-opsonized K. pneumoniae (30:1), and phagocytosis or killing was evaluated. Leukotriene C(4) and nitric oxide were quantified by the EIA and Griess methods, respectively. The results showed that AMs from sensitized and challenged rats presented a markedly increased phagocytic capacity via FcgammaR (10X compared to controls) and enhanced killing of K. pneumoniae (4X higher than controls). The increased phagocytosis was inhibited 15X and killing 3X by treatment of the rats with montelukast, as compared to the non-treated group. cys-LT addition increased phagocytosis in control AMs but had no effect on macrophages from allergic lungs. Montelukast reduced nitric oxide (39%) and LTC(4) (73%). These results suggest that LTs produced during allergic lung inflammation potentiate the capacity of AMs to phagocytose and kill K. pneumonia via FcgammaR.

Topics: Acetates; Allergens; Animals; Asthma; Cyclopropanes; Cysteine; Disease Models, Animal; Klebsiella pneumoniae; Leukotriene Antagonists; Leukotriene C4; Leukotrienes; Lung; Macrophages, Alveolar; Male; Nitric Oxide; Ovalbumin; Phagocytosis; Pneumonia; Quinolines; Rats; Rats, Wistar; Receptors, IgG; Sulfides

The present study has been designed to explore the protective effect of montelukast (leukotriene receptor antagonist) against intrastriatal quinolinic acid (QA; 300 nmol) and malonic acid (MA; 6 μmol) induced Huntington's like symptoms in rats. Quinolinic acid has been reported to induce excitotoxicity by stimulating the N-methyl-D-aspartate receptor, causing calcium overload which in turn leads to the neurodegeneration. On the other hand, MA, being a reversible inhibitor of mitochondrial enzyme complex-II, leads to energy crisis and free radical generation. Recent studies have reported the therapeutic potential of leukotriene receptor antagonists in different neurodegenerative disorders. However, their exact role is yet to be established. The present study accordingly, is an attempt to investigate the effect of montelukast against QA and MA induced behavioral, biochemical and molecular alterations in rat striatum. Oxidative stress, mitochondrial enzyme complex and tumor necrosis factor-alpha (TNF-α) were evaluated on day 21st and 14th post intrastriatal QA and MA treatment, respectively. Findings of the present study demonstrate significant alteration in the locomotor activity and motor coordination as well as oxidative burden (increased lipid peroxidation, nitrite concentration and decreased endogenous antioxidants), mitochondrial enzyme complex (I, II and IV) activities and TNF-α level, in both intrastriatal QA and MA treated animals. Further, montelukast (0.4, 0.8 mg/kg p.o.) treatment for 21 and 14 days respectively, attenuated the behavioral alterations, oxidative stress, mitochondrial dysfunction and TNF-α level in these models of Huntington's disease in a significant manner. In conclusion, the present study emphasizes the neuroprotective potential of montelukast in the therapeutic management of Huntington like symptoms.

Topics: Acetates; Analysis of Variance; Animals; Behavior, Animal; Body Weight; Brain; Brain Chemistry; Catalase; Cyclopropanes; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Gene Expression Regulation; Lipid Peroxidation; Male; Malonates; Mitochondria; Motor Activity; Neuroprotective Agents; Neurotoxicity Syndromes; Nitrites; Quinolines; Quinolinic Acid; Rats; Rats, Wistar; Sulfides; Superoxide Dismutase; Tetrazolium Salts; Thiazoles; Tumor Necrosis Factor-alpha

Hepatic ischemia-reperfusion injury (I/R) may occur in transplantation, trauma, and elective hepatic resections. Leukotrienes have been shown to play a major role in hepatic I/R injury. Five-lipoxygenase enzyme is an important enzyme in the production of leukotrienes from arachidonic acid. MK-886 is an inhibitor of 5-lipoxygenase, and montelukast is a cysteinyl leukotriene receptor antagonist. The aim of this study was to investigate whether MK-886 and montelukast are effective in preventing hepatic I/R injury.. Rats were divided into five groups consisting of seven rats in each: (1) Control I/R, (2) Control-montelukast, (3) Control-MK-886, (4) I/R+montelukast, and (5) I/R+MK-886. Thirty min of total hepatic vascular occlusion and then 60 min reperfusion were performed to animals in groups 1, 4, and 5. In groups 2 and 4, montelukast, and in groups 3 and 5, MK-886 was applied intraperitoneally before and during the surgical procedures.. Apoptosis in the liver and intestine decreased significantly in the I/R+montelukast and I/R+MK-886 groups compared with the I/R group. Tissue malondialdehyde levels and glutathione consumptions also decreased significantly in the I/R+montelukast and I/R+MK-886 groups compared with the I/R group. The difference in serum alanine aminotransferase and aspartate aminotransferase levels between the groups did not reach significance.. Montelukast and MK-886 were found to be effective in prevention of liver and intestine injury by reducing apoptosis and oxidative stress in a hepatic I/R model. Anti-inflammatory properties and inhibition of lipid peroxidation by montelukast and MK-886 could be protective for these organs in I/R injury.

Topics: Acetates; Animals; Cyclopropanes; Disease Models, Animal; Indoles; Leukotriene Antagonists; Lipoxygenase Inhibitors; Liver Diseases; Male; Quinolines; Rats; Rats, Wistar; Reperfusion Injury; Sulfides

Wound contractures can cause severe deformities and disabilities. Recent studies have suggested that leukotriene receptor antagonists have an inhibitory effect on the healing contraction process. This study aimed to evaluate the influence of the leukotriene inhibitor montelukast on the cutaneous healing process and the wound contraction phenomenon in rats.. For this study, 60 male rats were randomly divided into four groups (MK-7d, SF-7d, MK-14d, and SF-14d) according to the drug given through a rigid orogastric tube (MK group: montelukast 10 mg/kg/day; SF group: normal saline solution) and the day the animals were killed (7d: postoperative day 7; 14d: postoperative day 14). An excisional wound (2 x 2 cm) was created on the dorsum of each rat. The wounds were left open to heal spontaneously and documented by standard digital photographs on different postoperative days. Wound contraction rates were calculated with specific software, and specimens were histologically evaluated using picrosirius red stain. Results were analyzed using the Aspin-Welch, Mann-Whitney, and t tests, assuming a significance level of 5%.. The wound contraction rates were similar between the control and study groups (p > 0.05). On postoperative day 7, the wounds showed a marginally significant reduction in collagen maturation in the study group (40.1% +/- 6.88% vs 61.2% +/- 8.02%; p = 0.0607). On postoperative day 14, this reduction was statistically significant in the MK group (26% +/- 5.66% vs 68.3% +/- 7.76%; p = 0.0001).. Montelukast does not alter the contraction rate of excisional wounds in rats but has a significant and progressive inhibitory effect on collagen maturation.

Topics: Acetates; Animals; Collagen; Cyclopropanes; Dermatologic Surgical Procedures; Disease Models, Animal; Leukotriene Antagonists; Male; Probability; Quinolines; Random Allocation; Rats; Rats, Wistar; Reference Values; Sensitivity and Specificity; Skin; Statistics, Nonparametric; Sulfides; Wound Healing

We recently demonstrated that the T-helper type 1 (Th1) immune response plays an important role in the development of non-eosinophilic inflammation induced by airway exposure of an allergen plus double-stranded RNA (dsRNA). However, the role of lipoxygenase (LO) metabolites in the development of Th1 inflammation is poorly understood.. To evaluate the role of LO metabolites in the development of Th1 inflammation induced by sensitization with an allergen plus dsRNA.. A Th2-allergic inflammation mouse model was created by an intraperitoneal injection of lipopolysaccharide-depleted ovalbumin (OVA, 75 microg) and alum (2 mg) twice, and the Th1 model was created by intranasal application of OVA (75 microg) and synthetic dsRNA [10 microg of poly(I : C)] four times, followed by an intranasal challenge with 50 microg of OVA four times. The role of LO metabolites was evaluated using two approaches: a transgenic approach using 5-LO(-/-) and 15-LO(-/-) mice, and a pharmacological approach using inhibitors of cysteinyl leucotriene receptor-1 (cysLTR1), LTB4 receptor (BLT1), and 15-LO.. We found that the Th1-allergic inflammation induced by OVA+dsRNA sensitization was similar between 5-LO(-/-) and wild-type (WT) control mice, although Th2 inflammation induced by sensitization with OVA+alum was reduced in the former group. In addition, dsRNA-induced Th1 allergic inflammation, which is associated with down-regulation of 15-hydroxyeicosateraenoic acids production, was not affected by treatment with cysLTR1 or BLT1 inhibitors, whereas it was significantly lower in 12/15-LO(-/-) mice compared with WT control mice. Moreover, dsRNA-induced allergic inflammation and the recruitment of T cells following an allergen challenge were significantly inhibited by treatment with a specific 15-LO inhibitor (PD146176).. 15-LO metabolites appear to be important mediators in the development of Th1-allergic inflammation induced by sensitization with an allergen plus dsRNA. Our findings suggest that the 15-LO pathway is a novel therapeutic target for the treatment of virus-associated asthma characterized by Th1 inflammation.

Topics: Acetates; Allergens; Alum Compounds; Animals; Arachidonate 15-Lipoxygenase; Arachidonate 5-Lipoxygenase; Cyclopropanes; Disease Models, Animal; Fatty Alcohols; Fluorenes; Glycols; Hypersensitivity; Inflammation; Leukotriene Antagonists; Lipoxygenase Inhibitors; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Ovalbumin; Poly I-C; Quinolines; Receptors, Leukotriene; Receptors, Leukotriene B4; RNA, Double-Stranded; Sulfides; Th1 Cells; Th2 Cells

Prostaglandin (PG) D(2) is the major cylooxygenase metabolite released by mast cells upon allergen stimulation, and elicits responses through either the prostanoid DP1 receptor and/or the chemoattractant receptor homologous molecule expressed on T-helper type 2 (Th2) cells (CRTH2/DP2). Experimental evidence suggests that stimulation of one or both these receptors contributes to asthma pathophysiology.. The aim of this study was to test the hypothesis that the prostanoid DP1 receptor contributes to asthma pathophysiology by determining the efficacy of an orally active antagonist for this receptor, S-5751, on allergen-induced bronchoconstriction, airway hyperresponsiveness (AHR) and cellular inflammation in the sheep model of asthma.. PGD(2)-induced cyclic adenosine monophosphate (cAMP) production in platelet-rich plasma was used to establish the in vitro efficacy of S-5751. In vivo, sheep naturally allergic to Ascaris suum were challenged with an aerosolized antigen with and without S-5751 treatment (given 4 days before and for 6 days after the challenge).. S-5751 inhibited PGD(2)-induced cAMP production in platelet-rich plasma with an IC(50) value of 0.12 microm. S-5751 at 30 mg/kg, but not at 3 mg/kg, reduced the early bronchoconstriction and inhibited the late bronchoconstriction. AHR and inflammatory cell infiltration in bronchoalveolar lavage fluid at days 1 and 7 were also inhibited with the 30 mg/kg dose. The responses observed with S-5751 at 30 mg/kg were comparable with those with montelukast treatment (0.15 mg/kg, twice a day, intravenous); however, S-5751 did not block inhaled leukotrieneD(4)-induced broncoconstriction.. Prostanoid DP1 receptor inhibition may represent an alternative target for asthma therapy.

Topics: Acetates; Allergens; Animals; Anti-Asthmatic Agents; Asthma; Bronchoalveolar Lavage Fluid; Bronchoconstriction; Cyclic AMP; Cyclopropanes; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Humans; Prostaglandin D2; Quinolines; Receptors, Immunologic; Receptors, Prostaglandin; Sulfides; Thiophenes; Time Factors

Oral cysteinyl-leukotriene (LT) receptor antagonists such as montelukast are used for reducing airway inflammation and exacerbations. However, inhaled therapy using LT receptor antagonists has not been studied. In the present study, the effect of inhaled montelukast was investigated on airway hyperresponsiveness measured by cysteinyl-LT induced bronchoconstriction in an animal model of asthma. Bronchoconstriction responses were induced by inhaled LTC4 and LTD4 (0.2 microg/ml each) or three doses of intravenous LTC4 and LTD4 (0.3, 1, 3 microg/kg) in ovalbumin (OVA)-sensitized Hartley male guinea-pigs. The response was measured by the change in peak pressure of airway opening (Pao). The effect of montelukast was evaluated by the comparison of bronchoconstriction responses between the groups of animals pre-treated with 15-min inhalation of 10mg/ml montelukast and saline. To evaluate the tissue injury which might be caused by montelukast inhalation, lung tissues were examined for the histology. The broncoconstriction responses induced by inhaled LTC4 and LTD4 were enhanced by OVA sensitization in the guinea-pigs. In sensitized animals, the significant increases in peak Pao were 18.5+/-2.1 cmH(2)O by LTC4 inhalation and 25.0+/-1.6 cmH(2)O by LTD4 inhalation on average. Prior treatment of inhaled montelukast potently suppressed the peak Pao increases induced by both inhaled and intravenous LTC4 and LTD4 (all P<0.01 vs. saline control). Moreover, the suppression of inhaled montelukast against LTD4-induced bronchoconstriction was observed for at least up to 24h. According to the histological examination, montelukast inhalation produced no injury to the lung tissue. Inhaled montelukast, a cysteinyl-LT receptor antagonist, was effective in inhibiting cysteinyl-LT-induced acute bronchoconstriction, and may have the potential for clinical use as a new asthma drug.

Topics: Acetates; Administration, Inhalation; Animals; Asthma; Bronchial Hyperreactivity; Bronchoconstriction; Cyclopropanes; Cysteine; Disease Models, Animal; Guinea Pigs; Immunologic Factors; Leukotriene Antagonists; Leukotriene C4; Leukotriene D4; Leukotrienes; Lung; Male; Ovalbumin; Quinolines; Sulfides

We aimed to assess the efficiency of clarithromycin, montelukast, and pentoxifylline treatments, alone and in combination, in reducing hyperoxic lung injury at the histopathologic level.. The experiment was carried out with 47 newborn rat pups divided into six groups during postnatal days 3 to 13. The rats belonging to group 1 were designated as the control group and kept in room air without exposure to hyperoxia. Group 2 (clarithromycin), group 3 (montelukast), group 4 (pentoxifylline), group 5 (clarithromycin + montelukast + pentoxifylline combination), and group 6 (placebo) were kept in plexiglass chamber and exposed to hyperoxia (88-92%) throughout the experiment. Alveolar surface area percentage, fibrosis, and smooth muscle actin expression were assessed in the lungs, which were resected by thoracotomy on postnatal day 14.. Drug treatments, when used separately, were not detected to be superior to placebo with regard to mean alveolar surface area, fibrosis, and smooth muscle actin expression. Combination treatment resulted in significantly higher mean lung area percentages and lower actin scores with respect to the placebo treatment group (64.0% vs. 50.2%, p=0.002; 0 (0-1) vs. 7 (2-12), p=0.005, respectively).. It was determined that clarithromycin, montelukast, and pentoxifylline combination treatment is superior to placebo treatment in the newborn rat hyperoxic lung injury model. The present study indicates that combination therapy might be successful in bronchopulmonary dysplasia, which has complex pathophysiologic processes and lacks established efficient treatment strategies.

Topics: Acetates; Animals; Animals, Newborn; Anti-Inflammatory Agents, Non-Steroidal; Bronchopulmonary Dysplasia; Clarithromycin; Cyclopropanes; Disease Models, Animal; Drug Therapy, Combination; Humans; Infant, Newborn; Leukotriene Antagonists; Oxygen Inhalation Therapy; Pentoxifylline; Quinolines; Rats; Sulfides

Cordyceps militaris is a well-known fungus with immunomodulatory activity. It is generally used in traditional Chinese medicine to treat hemoptysis, bronchial or lung inflammation, and urogenital disorders. The purpose of our study was to evaluate the effect of cultivated C. militaris on airway inflammation in a mouse asthma model.. BALB/c mice were sensitized with intraperitoneal ovalbumin (OVA) on Days 0 and 14, and were then given intranasal OVA on Day 14 and Days 25-27. Randomized treatment groups of sensitized mice were administered C. militaris, prednisolone, montelukast, or placebo by gavage from Days 15-27. Airway hyperreactivity to aerosolized methacholine was determined. Bronchoalveolar lavage fluid and serum were analyzed to assess airway inflammation.. OVA-sensitized mice developed a significant airway inflammatory response that was inhibited by prednisolone and montelukast, whilst C. militaris reduced airway inflammation less effectively. Airway hyperresponsiveness to methacholine was observed in OVA-sensitized mice and was reversed by both prednisolone and montelukast. C. militaris initially reversed airway hyperreactivity, but this effect disappeared at higher methacholine doses.. C. militaris can modulate airway inflammation in asthma, but it is less effective than prednisolone or montelukast. These results demonstrate that C. militaris is unable to adequately block the potent mediators of asthmatic airway inflammation.

Topics: Acetates; Animals; Anti-Asthmatic Agents; Asthma; Cordyceps; Cyclopropanes; Disease Models, Animal; Female; Immunologic Factors; Mice; Mice, Inbred BALB C; Prednisolone; Quinolines; Random Allocation; Sulfides

Cough variant asthma is known as a major cause of chronic cough. Fundamental features of cough variant asthma are prolonged non-productive cough responding to bronchodilator therapy, no history of wheezing or dyspnea attack, normal cough sensitivity and slightly increased bronchial responsiveness. Recently, we reported the animal model of cough variant asthma. The aim of this study was to clarify the involvement of cysteinyl leukotrienes (cysLTs) in this model by using a specific leukotriene receptor antagonist, montelukast. Cough number and specific airway resistance (sRaw) were measured during the antigen inhalation (1.5 min) and following 18.5 min, which was carried out 72 h after the first antigen inhalation in actively sensitized guinea pigs, and then total cell number and cell differentials in bronchoalveolar lavage fluid (BALF) were measured. Montelukast significantly reduced the antigen re-inhalation-induced cough, increase in sRaw, and increase in total cell number in BALF. In conclusion, cysLTs may play an important part in antigen-induced cough associated with bronchoconstriction and airway inflammation in cough variant asthma.

Topics: Acetates; Airway Resistance; Animals; Anti-Asthmatic Agents; Asthma; Bronchial Provocation Tests; Bronchoalveolar Lavage Fluid; Cough; Cyclopropanes; Disease Models, Animal; Guinea Pigs; Leukotrienes; Male; Ovalbumin; Quinolines; Sulfides

Different drugs from various pharmacological classes were compared for their ability to protect against the nasal effects of acute allergen challenge in a guinea pig model. In the model, sneezing and nose rubbing were recorded after an initial allergen challenge in guinea pigs previously sensitized to egg albumin. Four days later the same guinea pigs were re-challenged a second time when anesthetised. In these anaesthetized animals, nasal airway pressure, pulmonary inflation pressure and cellular infiltration into nasal lavage fluid were measured. The drug tested were autacoid antagonists (mepyramine--3mg/kg, cetirizine--3mg/kg and montelukast--10mg/kg), L-NAME (10 or 20mg/kg), heparin (20mg/kg) and dexamethasone (20mg/kg) given either intraperitoneally or intravenously; all were given shortly before challenge. Sneezing induced by allergen challenge was statistically significantly reduced by mepyramine, cetirizine and dexamethasone whereas only cetirizine reduced nose rubbing. Changes in nasal airway pressure due to allergen exposure were reduced by cetirizine, montelukast, L-NAME, and heparin, but not by mepyramine, nor dexamethasone. In the presence of L-NAME, nasal airway pressure actually changed in the opposite direction. Cellular infiltration, as assessed by cytometry in nasal lavage fluid 60min after acute allergen challenge, was reduced by montelukast and heparin but not by antihistamines, L-NAME nor dexamethasone. This pattern of effects of the drugs, given by doses and routes previously described in the literature as being effective was not completely consistent with expected responses. The lack of effect of dexamethasone probably reflects the fact that it was given acutely whereas in the clinic chronic administration is used. The two antihistamines were not identical in their actions, presumably reflecting the fact that cetirizine has therapeutic actions not entirely confined to blockade of H1 receptors. Montelukast has not been reported to have major effects on sneezing and itching in the clinic but reduces nasal obstruction (lower nasal airway pressure or nasal patency). Montelukast's effects on cellular infiltration indicate the possible involvement of leukotrienes. Heparin has actions on inflammatory cell infiltration. This could explain its profile of reducing both cellular infiltration, and increased nasal airway pressure.

Topics: Acetates; Acute Disease; Animals; Cetirizine; Cyclopropanes; Dexamethasone; Disease Models, Animal; Guinea Pigs; Heparin; Histamine H1 Antagonists; Male; Nasal Obstruction; NG-Nitroarginine Methyl Ester; Ovalbumin; Pyrilamine; Quinolines; Rhinitis, Allergic, Seasonal; Sneezing; Sulfides

KP-496 is a novel dual antagonist for cysteinyl leukotriene receptor 1 (CysLT(1)) and thromboxane A(2) (TXA(2)) receptor (TP). The aim of this study was to evaluate the pharmacological profile of inhaled KP-496 and its effects on airway obstruction.. Antagonist activities of inhaled KP-496 were investigated using bronchoconstriction induced in guinea pigs by LTD(4) or U46619, a stable TXA(2) mimetic. Guinea pigs sensitized with injections of ovalbumin were used to assess the effects of inhaled KP-496 on bronchoconstriction induced by antigen (i.v.). Another set of guinea pigs were sensitized and challenged with ovalbumin by inhalation and the effects of inhaled KP-496 on immediate and late airway responses and airway hyperresponsiveness were investigated.. KP-496 significantly inhibited LTD(4)- and U46619-induced bronchoconstriction in a dose-dependent manner. The inhibitory effects of KP-496 (1%) were comparable to those of montelukast (a CysLT(1) antagonist, p.o., 0.3 mg kg(-1)) or seratrodast (a TP antagonist, p.o., 3 mg kg(-1)). KP-496 (1%) and oral co-administration of montelukast (10 mg kg(-1)) and seratrodast (20 mg kg(-1)) significantly inhibited antigen-induced bronchoconstriction, whereas administration of montelukast or seratrodast separately did not inhibit antigen-induced bronchoconstriction. KP-496 exhibited dose-dependent and significant inhibitory effects on the immediate and late airway responses and airway hyperresponsiveness following antigen challenge.. KP-496 exerts effects in guinea pigs which could be beneficial in asthma. These effects of KP-496 were greater than those of a CysLT(1) antagonist or a TP antagonist, in preventing antigen-induced airway obstruction.

Topics: 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; Acetates; Administration, Inhalation; Administration, Oral; Airway Obstruction; Animals; Anti-Asthmatic Agents; Benzoates; Benzoquinones; Bronchoconstriction; Cyclopropanes; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Therapy, Combination; Guinea Pigs; Heptanoic Acids; Leukotriene Antagonists; Leukotriene D4; Lung; Male; Membrane Proteins; Ovalbumin; Prostaglandin Antagonists; Quinolines; Receptors, Leukotriene; Receptors, Thromboxane A2, Prostaglandin H2; Respiratory Hypersensitivity; Sulfides; Thiazoles; Time Factors

5-lipoxygenase (5-LO) is the key enzyme in leukotriene (LT) biosynthesis from arachidonic acid (AA). Here, we examined the role of the 5-LO-product, cysteinyl-LT (Cys-LT), with a 5-LO inhibitor (zileuton) and a Cys-LT, receptor antagonist (montelukast), in the inflammatory response and tissue injury associated with spinal cord injury (SCI).. SCI was induced in mice by the application of vascular clips to the dura via a two-level T6 to T7 laminectomy for 1 min. Cord inflammation was assessed histologically and by measuring inflammatory mediators (ELISA) and apoptosis by annexin V, TUNEL, Fas ligand staining and Bax and Bcl-2 expression (immunohistochemistry and western blots). Motor function in hindlimbs was assessed by a locomotor rating scale, for 10 days after cord injury.. SCI in mice resulted in tissue damage, oedema, neutrophil infiltration, apoptosis, tumour necrosis-alpha (TNF-alpha) and cyclooxygenase-2 (COX-2) expression, prostaglandin E(2) (PGE(2)) and leukotriene B(4) (LTB(4)) production, and extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation in injured tissue. Treatment of the mice with zileuton or montelukast reduced the spinal cord inflammation and tissue injury, neutrophil infiltration, TNF-alpha, COX-2 and pERK1/2 expression, PGE(2) and LTB(4) production, and apoptosis. In separate experiments, zileuton or montelukast significantly improved the recovery of limb function over 10 days.. Zileuton and montelukast produced a substantial reduction of inflammatory events associated with experimental SCI. Our data underline the important role of 5-LO and Cys-LT in neurotrauma.

Topics: Acetates; Animals; Apoptosis; Arachidonate 5-Lipoxygenase; Cyclooxygenase 2; Cyclopropanes; Cysteine; Dinoprostone; Disease Models, Animal; Gene Expression Regulation; Hydroxyurea; Inflammation; Leukotrienes; Lipoxygenase Inhibitors; Male; Mice; Neutrophil Infiltration; Quinolines; Recovery of Function; Spinal Cord Injuries; Sulfides; Tumor Necrosis Factor-alpha

Cellular recruitment during inflammatory/immune responses is tightly regulated. The ability to dampen inflammation is imperative for prevention of chronic immune responses, as in asthma. Here we investigated the ability of lipoxin A4 (LXA4) stable analogs to regulate airway responses in two allergen-driven models of inflammation. A 15-epi-LXA4 analog (ATLa) and a 3-oxa-15-epi-LXA4 analog (ZK-994) prevented excessive eosinophil and T lymphocyte accumulation and activation after mice were sensitized and aerosol-challenged with ovalbumin. At <0.5 mg/kg, these LXA4 analogs reduced leukocyte trafficking into the lung by >50% and to a greater extent than equivalent doses of the CysLT1 receptor antagonist montelukast. Distinct from montelukast, ATLa treatment led to marked reductions in cysteinyl leukotrienes, interleukin-4 (IL-4), and IL-10, and both ATLa and ZK-994 inhibited levels of IL-13. In cockroach allergen-induced airway responses, both intraperitoneal and oral administration of ZK-994 significantly reduced parameters of airway inflammation and hyper-responsiveness in a dose-dependent manner. ZK-994 also significantly changed the balance of Th1/Th2-specific cytokine levels. Thus, the ATLa/LXA4 analog actions are distinct from CysLT1 antagonism and potently block both allergic airway inflammation and hyper-reactivity. Moreover, these results demonstrate these analogs' therapeutic potential as new agonists for the resolution of inflammation.

Topics: Acetates; Allergens; Animals; Anti-Asthmatic Agents; Anti-Inflammatory Agents, Non-Steroidal; Antigens, Plant; Cyclopropanes; Disease Models, Animal; Leukotriene Antagonists; Lipoxins; Male; Membrane Proteins; Mice; Mice, Inbred BALB C; Ovalbumin; Phenyl Ethers; Quinolines; Receptors, Leukotriene; Respiratory Hypersensitivity; Structure-Activity Relationship; Sulfides

In this work we have evaluated the clinical responses of pneumovirus-infected mice to combination therapy with the antiviral agent, ribavirin, and the CysLT1 cysteinyl leukotriene receptor antagonist, montelukast. We observed substantial virus replication in our mouse model of pneumovirus infection and significant accumulation of cysteinyl leukotrienes in lung tissue, the latter detected at levels that correlate directly with granulocyte recruitment to the airways. While administration of the nucleoside analog, ribavirin, reduced virus replication approximately 2,000-fold, the clinical outcomes as measured by morbidity and mortality, in response to ribavirin monotherapy were indistinguishable from those of the no-treatment controls. Similarly, montelukast therapy alone did not reduce granulocyte recruitment nor did it improve the clinical outcome. However, combined therapy with ribavirin and montelukast resulted in a significant reduction in morbidity and a substantial reduction in mortality (50% survival at t = 14 days and onward, compared to 10-20% survival in response to montelukast alone or to ribavirin alone, respectively, p < 0.01). These findings define further the independent contributions made by virus replication and by the ensuing inflammatory response to the detrimental sequelae of pneumovirus infection in vivo.

Topics: Acetates; Animals; Antiviral Agents; Bronchiolitis, Viral; Cyclopropanes; Cysteine; Disease Models, Animal; Drug Therapy, Combination; Humans; Leukotriene Antagonists; Leukotrienes; Lung; Mice; Mice, Inbred C57BL; Murine pneumonia virus; Pneumovirus Infections; Quinolines; Ribavirin; Sulfides; Treatment Outcome; Virus Replication

Airway inflammation in asthma is accompanied by structural changes, including goblet cell metaplasia, smooth muscle cell layer thickening, and subepithelial fibrosis. This allergen-induced airway remodeling can be replicated in a mouse asthma model.. The study goal was to determine whether established airway remodeling in a mouse asthma model is reversible by administration of the cysteinyl leukotriene (CysLT)1 receptor antagonist montelukast, the corticosteroid dexamethasone, or the combination montelukast + dexamethasone.. BALB/c mice, sensitized by intraperitoneal ovalbumin (OVA) as allergen, received intranasal OVA periodically Days 14-73 and montelukast or dexamethasone or placebo from Days 73-163.. Allergen-induced trafficking of eosinophils into the bronchoalveolar lavage fluid and lung interstitium and airway goblet cell metaplasia, smooth muscle cell layer thickening, and subepithelial fibrosis present on Day 73 persisted at Day 163, 3 mo after the last allergen challenge. Airway hyperreactivity to methacholine observed on Day 73 in OVA-treated mice was absent on Day 163. In OVA-treated mice, airway eosinophil infiltration and goblet cell metaplasia were reduced by either montelukast or dexamethasone alone. Montelukast, but not dexamethasone, reversed the established increase in airway smooth muscle mass and subepithelial collagen deposition. By immunocytochemistry, CysLT1 receptor expression was significantly increased in airway smooth muscle cells in allergen-treated mice compared with saline-treated controls and was reduced by montelukast, but not dexamethasone, administration.. These data indicate that established airway smooth muscle cell layer thickening and subepithelial fibrosis, key allergen-induced airway structural changes not modulated by corticosteroids, are reversible by CysLT1 receptor blockade therapy.

Topics: Acetates; Animals; Asthma; Cyclopropanes; Disease Models, Animal; Female; Follow-Up Studies; Glucocorticoids; Leukotriene Antagonists; Lung; Membrane Proteins; Mice; Mice, Inbred BALB C; Muscle, Smooth; Quinolines; Receptors, Leukotriene; Respiratory Mucosa; Sulfides; Treatment Outcome

Allergic inflammation of the airways has a critical role in asthma development. We investigated a suppressive effect of verproside (3,4-dihydroxy catalpol) isolated from the extract of Pseudolysimachion longifolium on asthmatic parameters--such as immunoglobulin E (IgE) level, cytokine release, eosinophilia, airway hyperresponsiveness and mucus hypersecretion--in an OVA-sensitized/challenged mouse model. Verproside significantly inhibited the increase of total IgE and the cytokines IL-4 and IL-13 in plasma and bronchoalveolar lavage fluid, and also effectively suppressed airway hyperresponsiveness, eosinophilia and mucus hypersecretion in OVA-induced asthmatic mice. The efficacy of verproside was comparable to montelukast, an anti-asthmatic drug that is currently available. These results suggest that verproside could be a major marker in herbal medicines that are used for asthma treatment, and could also act as a lead for anti-asthmatic drugs.

Topics: Acetates; Animals; Anti-Asthmatic Agents; Asthma; Bronchoalveolar Lavage Fluid; Cyclopropanes; Disease Models, Animal; Female; Glucosides; Immunoglobulin E; Interleukin-13; Interleukin-4; Iridoid Glucosides; Iridoids; Lung; Methacholine Chloride; Mice; Mice, Inbred BALB C; Molecular Structure; Mucus; Ovalbumin; Plant Extracts; Pneumonia; Pulmonary Eosinophilia; Quinolines; Sulfides; Veronica

Airway structural changes that occur in patients with asthma in response to persistent inflammation are termed airway remodeling. The cysteinyl leukotrienes (LTC(4), D(4) and E(4)) are known to play important roles in the pathobiology of asthma. To evaluate the effect of low dose montelukast (MK) on the development of airway remodeling using a chronic murine model of allergic airway inflammation with subepithelial fibrosis, BALB/c mice, after intraperitoneal ovalbumin (OVA) sensitization on days 0 and 14, received intranasal OVA periodically on days 14-75. MK treated mice received montelukast sodium intraperitoneally on days 26-75. The OVA sensitized/challenged mice developed an extensive eosinophil cell inflammatory response, goblet cell hyperplasia, mucus occlusion, and smooth muscle hypertrophy of the airways. In addition, in OVA sensitized/challenged mice, dense collagen deposition/fibrosis was seen throughout the lung interstitium surrounding the airways, blood vessels, and alveolar septae. The cysteinyl leukotriene 1 (CysLT1) receptor antagonist, MK significantly reduced the airway eosinophil infiltration, goblet cell hyperplasia, mucus occlusion, and lung fibrosis except airway smooth muscle hypertrophy in the OVA sensitized/challenged mice. The OVA sensitized/challenged mice had significantly increased epithelial desquamation compared with control mice. MK markedly reduced epithelial desquamation of airways in OVA/MK treated animals compared with OVA sensitized/challenged mice. MK treatment did not affect the levels of CysLT in lung tissue. Our results show that the important role of cysteinyl leukotrienes in the pathogenesis of asthma. Lower dose of CysLT1 receptor antagonism has a significant anti-inflammatory effect on allergen-induced lung inflammation and fibrosis but not airway smooth muscle hypertrophy in an animal model of asthma.

Topics: Acetates; Airway Obstruction; Animals; Anti-Asthmatic Agents; Asthma; Collagen; Cyclopropanes; Cysteine; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Goblet Cells; Hyperplasia; Hypertrophy; Leukotriene Antagonists; Leukotrienes; Lung; Mice; Mice, Inbred BALB C; Mucus; Muscle, Smooth; Pulmonary Fibrosis; Quinolines; Receptors, Leukotriene; Respiratory Mucosa; Sulfides

Adenosine produces bronchoconstriction in allergic rabbits, primates, and humans by activating adenosine A(1) receptors. Previously, it is reported that a high dose of L-97-1, a water-soluble, small molecule adenosine A(1) receptor antagonist, blocks early and late allergic responses, and bronchial hyper-responsiveness to histamine in a hyper-responsive rabbit model of allergic asthma. Effects of a lower dose of L-97-1 are compared to montelukast, a cysteinyl leukotriene-1 receptor antagonist on early allergic response, late allergic response, bronchial hyper-responsiveness, and inflammatory cells in bronchoalveolar lavage (BAL) fluid following house dust mite administration. Rabbits received intraperitoneal injections of house dust mite extract within 24 h of birth followed by booster house dust mite injections. Hyper-responsive rabbits received aerosolized house dust mite (2500 allergen units), 1 h after intragastric administration of L-97-1 (1 mg/kg) or montelukast (0.15 mg/kg) and lung dynamic compliance was measured for 6 h. Lung dynamic compliance was significantly higher following L-97-1 at all time points and with montelukast at 60-300 min following house dust mite (P<0.05). L-97-1 blocks both early and late allergic responses. Montelukast blocks only the late allergic response. Both L-97-1 and montelukast significantly blocked bronchial hyper-responsiveness at 24 h (P<0.05). Both L-97-1 and montelukast significantly reduced BAL eosinophils at 6 h and neutrophils at 6 and 24 h (P<0.05). L-97-1 significantly reduced BAL lymphocytes at 6 and 24 h (P<0.05). Montelukast significantly reduced BAL macrophages at 6 and 24 h (P<0.05). By blocking both bronchoconstriction and airway inflammation, L-97-1 may be an effective oral anti-asthma treatment.

Topics: Acetates; Adenosine A1 Receptor Antagonists; Animals; Anti-Asthmatic Agents; Asthma; Bronchial Hyperreactivity; Bronchial Provocation Tests; Bronchoalveolar Lavage Fluid; Cyclopropanes; Disease Models, Animal; Eosinophils; Histamine; Inflammation; Leukotriene Antagonists; Lung Compliance; Lymphocytes; Macrophages, Alveolar; Neutrophils; Purines; Pyroglyphidae; Quinolines; Rabbits; Sulfides; Time Factors

Previous genetic analysis has shown that a deletion in the complement component 5 gene-coding region renders mice more susceptible to allergen-induced airway hyperresponsiveness (AHR) due to reduced IL-12 production. We investigated the role of complement in a murine model of asthma-like pulmonary inflammation.. In order to evaluate the role of complement B10 mice either sufficient or deficient in C5 were studied. Both groups of mice immunized and challenged with a house dust extract (HDE) containing high levels of cockroach allergens. Airways hyper-reactivity was determined with whole-body plesthysmography. Bronchoalveolar lavage (BAL) was performed to determine pulmonary cellular recruitment and measure inflammatory mediators. Lung homogenates were assayed for mediators and plasma levels of IgE determined. Pulmonary histology was also evaluated.. C5-deficient mice showed enhanced AHR to methylcholine challenge, 474% and 91% increase above baseline Penh in C5-deficient and C5-sufficient mice respectively, p < 0.001. IL-12 levels in the lung homogenate (LH) were only slightly reduced and BAL IL-12 was comparable in C5-sufficient and C5-deficient mice. However, C5-deficient mice had significantly higher cysteinyl-leukotriene levels in the BAL fluid, 1913 +/- 246 pg/ml in C5d and 756 +/- 232 pg/ml in C5-sufficient, p = 0.003.. These data demonstrate that C5-deficient mice show enhanced AHR due to increased production of cysteinyl-leukotrienes.

Topics: Acetates; Allergens; Animals; Asthma; Bronchoalveolar Lavage Fluid; Bronchoconstriction; Choline; Cockroaches; Complement C5; Cyclopropanes; Disease Models, Animal; Dust; Genetic Predisposition to Disease; Immunoglobulin E; Interleukin-12; Leukotriene Antagonists; Leukotrienes; Mice; Mice, Knockout; Quinolines; Respiratory Hypersensitivity; Sulfides

Experimental allergic rhinitis produces enhanced cough response in awake guinea pigs. Leukotriene receptor antagonists, as anti-inflammatory agents, have been effective in treatment of asthma and allergic rhinitis to inhibit the early and late allergic response. In the present study, we evaluated the effect of montelukast (Singulair, Merck, USA) on the cough reflex in an experimental model of allergen-induced rhinitis in guinea pigs. Guinea pigs (n=16) were sensitized with intraperitoneal ovalbumin (OVA). The animals were then used to develop a model of allergic rhinitis by repeated intranasal instillation of 0.5% OVA at weekly intervals for 8 weeks. Allergic rhinitis was evaluated from the occurrence of typical clinical symptoms including sneezing, conjunctival and nasal secretion, or nasal acoustic phenomenon. Between the 6(th) and 8(th) nasal challenge (NCh) the animals (n=8) were treated daily for 14 days with oral montelukast (10mg/kg). Cough was induced by citric acid aerosol inhalation in gradually increasing concentration (0.05-1.6 M) and was evaluated before sensitization and then after the 1(st), 6(th), and 8(th) nasal challenge when rhinitis symptoms were most conspicuous. The intensity of cough was significantly increased after the first and repeated nasal OVA challenges, and reduced after the 8(th) NCh that was preceded with montelukast treatment [9(6-14) vs. 16.5(14-22) vs. 25.5(23-42) vs. 8.5(8-13); P=0.0003]. We conclude that antileukotriene therapy suppresses the stimulating effect of experimental allergic rhinitis on the chemically-induced cough in awake guinea pigs.

Topics: Acetates; Administration, Oral; Animals; Citric Acid; Cough; Cyclopropanes; Disease Models, Animal; Guinea Pigs; Laryngeal Mucosa; Leukotriene Antagonists; Male; Membrane Proteins; Ovalbumin; Quinolines; Receptors, Leukotriene; Rhinitis, Allergic, Perennial; Sulfides; Time Factors

To study the relation between Interleukin-4 (IL-4), IL-5, IL-13, transforming growth factor-beta(2) (TGF-beta(2)) and airway remodeling and to investigate the effects of Montelukast (MK) on airway inflammation and airway remodeling of asthma.. Twenty female BALB/c mice were randomly divided into a remodeling group and a treatment group (MK group), with 10 BALB/c mice in each group. The mice were sensitized by ovalbumin (OVA), and only the MK group was treated with MK (15 mg/kg). The number of total cells and eosinophils in bronchoalveolar lavage fluid (BALF) were counted. Light and electronic microscope were used to detect the pathologic histology and morphologic change. In situ hybridization and reverse transcription-polymerase chain reaction (RT-PCR) were used to measure IL-4, L-5, IL-13, and TGF-beta(2) mRNAs in the lung.. The numbers of total cells and eosinophils in BALF of the remodeling group were (5.4 +/- 1.1) x 10(5)/ml and 2.32 +/- 0.20, while those of the treatment group were (3.9 +/- 1.6) x 10(5)/ml and 1.64 +/- 0.32, respectively, the difference being significant (P < 0.01). Histological and electronic microscopic examination showed extensive airway inflammation, notably accumulation of significant numbers of eosinophils and lymphocytes in the remodeling group. Other features including prominent proliferation of airway epithelial cells protruded like fingers, increased thickness of smooth muscle, hyperplasia of connective tissue, goblet cell hyperplasia and a marked increase in airway mucus secretion with mucus plugging and extensive collagen deposition around the airways were also noted in the remodeling group. In the treatment group, the inflammation was significantly decreased, with decreased production of mucus, decreased collagen and granule of mucus around airway, less proliferation of airway epithelium, smooth muscle hypertrophy and airway spasm. In situ hybridization showed that the expression of IL-13 mRNA and TGF-beta(2) mRNA in the lung of the remodeling group were 24 +/- 7 and 17 +/- 5 respectively, while those of the treatment group were 17 +/- 4 and 10 +/- 3. RT-PCR results showed that the absorbance of IL-4 mRNA and IL-5 mRNA in the lung of the remodeling group were 0.91 and 0.96, while those of the treatment group were 0.22 and 0.35; the differences between the groups were all significant (all P < 0.01).. MK could effectively inhibit airway remodeling, which suggests a possible role of cysteinyl leukotrienes in the pathogenesis of chronic allergic inflammation with fibrosis.

Topics: Acetates; Animals; Asthma; Bronchi; Cyclopropanes; Disease Models, Animal; Eosinophils; Female; Interleukins; Leukotriene Antagonists; Mice; Mice, Inbred BALB C; Quinolines; Random Allocation; RNA, Messenger; Sulfides; Transforming Growth Factor beta; Transforming Growth Factor beta2

Airway inflammation and remodeling in chronic asthma are characterized by airway eosinophilia, hyperplasia of goblet cells and smooth muscle, and subepithelial fibrosis. We examined the role of leukotrienes in a mouse model of allergen-induced chronic lung inflammation and fibrosis. BALB/c mice, after intraperitoneal ovalbumin (OVA) sensitization on Days 0 and 14, received intranasal OVA periodically Days 14-75. The OVA-treated mice developed an extensive eosinophil and mononuclear cell inflammatory response, goblet cell hyperplasia, and mucus occlusion of the airways. A striking feature of this inflammatory response was the widespread deposition of collagen beneath the airway epithelial cell layer and also in the lung interstitium in the sites of leukocytic infiltration that was not observed in the saline-treated controls. The cysteinyl leukotriene(1) (CysLT(1)) receptor antagonist montelukast significantly reduced the airway eosinophil infiltration, mucus plugging, smooth muscle hyperplasia, and subepithelial fibrosis in the OVA-sensitized/challenged mice. The presence of Charcot-Leyden-like crystals in airway macrophages and the increased interleukin (IL)-4 and IL-13 mRNA expression in lung tissue and protein in BAL fluid seen in OVA-treated mice were also inhibited by CysLT(1) receptor blockade. These data suggest an important role for cysteinyl leukotrienes in the pathogenesis of chronic allergic airway inflammation with fibrosis.

Topics: Acetates; Acute Disease; Allergens; Analysis of Variance; Animals; Asthma; Bronchoalveolar Lavage Fluid; Chronic Disease; Cyclopropanes; Disease Models, Animal; Drug Evaluation, Preclinical; Eosinophils; Fibrosis; Glycoproteins; Goblet Cells; Hyperplasia; Inflammation; Leukotriene Antagonists; Leukotrienes; Lysophospholipase; Macrophages, Alveolar; Mice; Ovalbumin; Quinolines; Respiratory Mechanics; Sulfides