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Airway Smooth Muscle Cells (airway + smooth_muscle_cell)
Selected AbstractsEndothelin-1 increases cholinergic nerve-mediated contraction of human bronchi via tachykinin synthesis inductionBRITISH JOURNAL OF PHARMACOLOGY, Issue 7 2001Bruno D'Agostino In some asthmatics, muscarinic receptor antagonists are effective in limiting bronchoconstrictor response, suggesting an abnormal cholinergic drive in these subjects. There is a growing body of evidences indicating that cholinergic neurotransmission is also enhanced by endothelin-1 (ET-1) in rabbit bronchi, mouse trachea and in human isolated airway preparations. We investigated the role of secondary mediators in ET-1 induced potentiation of cholinergic nerve-mediated contraction in human bronchi, in particular the possible role of neuropeptides in this phenomenon. Bronchial tissues after endothelin treatment were exposed to a standard electrical field stimulation (EFS) (30% of EFS 30Hz)-induced contraction. In addition, in some experiments, preparations were treated with a tachykinin NK2 receptor antagonist and subsequently exposed to the same protocol. HPLC and RIA were performed on organ bath fluid samples. Moreover, the human bronchi were used for the ,-PPT (preprotachykinin) mRNA extraction and semiquantitative reverse transcription polymerase chain reaction (RT , PCR), prior to and 30 , 40 min following ET-1 challenge. The selective tachykinin NK2 receptor antagonist, SR48968, was effective to reduce ET-1 potentiation of EFS mediated contraction. HPLC or RIA showed significant increased quantities of NKA in organ bath effluents after EFS stimulation in bronchi pretreated with ET-1. Finally, ,-PPT mRNA level after stimulation of bronchi with ET-1 was increased about 2 fold respect to control untreated bronchi. In conclusion, this study demonstrated that, at least in part, the ET-1 potentiation of cholinergic nerve-mediated contraction is mediated by tachykinin release, suggesting that in addition to nerves, several type of cells, such as airway smooth muscle cell, may participate to neuropeptide production. British Journal of Pharmacology (2001) 134, 1447,1454; doi:10.1038/sj.bjp.0704395 [source] Biotransformation in vitro of the 22R and 22S epimers of budesonide by human liver, bronchus, colonic mucosa and skinFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 1 2001Julio Cortijo The pharmacological effects of glucocorticoids are greatly influenced by their pharmacokinetic properties. In the present report, the in vitro biotransformation of the 22R and 22S epimers of the topical steroid budesonide was studied in the S-9 fraction of human liver, bronchus, skin and colonic mucosa. The disappearance of unchanged epimers of budesonide was measured during 90 min of incubation by high performance liquid chromatography. The rate of disappearance was high in human liver while little biotransformation occurred in bronchial tissue and colonic mucosa, and none was detected in the skin. A marked decay of the initial concentration of unchanged budesonide epimers was noticed after 2 h incubation in cultured human hepatocytes, while only a small decrease was observed after 24 h incubation in cultured human airway smooth muscle cells and BEAS-2B cells. The 22R epimer of budesonide suffered greater in vitro biotransformation than the 22S epimer in human hepatic, bronchial and colonic tissues. These findings extend those of other studies, and confirm that the high therapeutic ratio of budesonide is due to negligible local biotransformation combined with high level of liver metabolism for locally absorbed budesonide. [source] Differential expression of peroxisome proliferator activated receptor , and cyclin D1 does not affect proliferation of asthma- and non-asthma-derived airway smooth muscle cellsRESPIROLOGY, Issue 2 2010Justine Y. LAU ABSTRACT Background and objective: Airway remodelling involves thickening of the airway smooth muscle (ASM) bulk. Proliferation of asthma-derived ASM cells is increased in vitro, but underlying mechanisms remain unknown. Peroxisome proliferators activated receptor-, (PPAR,) regulates the cell cycle. It is suggested that PPAR, agonists have anti-inflammatory effects, which may be valuable in the treatment of asthma, but information regarding their antiproliferative properties in ASM is lacking. Although corticosteroids reduce airway inflammation, in vitro they inhibit proliferation in only non-asthma ASM cells by reducing cyclin D1. We therefore investigated the effects of mitogenic stimulation (foetal bovine serum (FBS)), and a PPAR, ligand (ciglitazone), on PPAR, and cyclin D1 expression and proliferation of ASM cells. In addition, we examined the effects of ciglitazone on ASM cell proliferation. Methods: We assessed PPAR, and cyclin D1 mRNA and protein levels using quantitative PCR and immunoblotting. Cell proliferation was assessed using bromodeoxyuridine uptake. Results: In the presence of 5% FBS, PPAR, and cyclin D1 expression decreased over time in non-asthmatic cells but increased in asthmatic cells (compared with sub-confluent cells). FBS-induced proliferation of asthmatic cells increased at all time points, but occurred only at day 7 with non-asthmatic cells (compared with unstimulated time-matched control). Ciglitazone increased PPAR, expression in both groups, but did not alter cell proliferation, while fluticasone increased PPAR, protein only in asthmatic cells. Conclusions: Although in the presence of a mitogenic stimulus, PPAR, was differentially expressed in asthma- and non-asthma-derived ASM; its expression was not related to the increased proliferation observed in asthmatic ASM. [source] Vitamin D and glucocorticoids differentially modulate chemokine expression in human airway smooth muscle cellsBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2008A Banerjee Background and purpose: Chemokines play a critical role in the pathogenesis of asthma and facilitate the recruitment of inflammatory cells in the airways. Evidence now suggests that airway smooth muscle (ASM) may serve as a source of chemokines in inflamed airways. Although vitamin D has potent anti-inflammatory properties in vitro in some cell types, its effects on ASM cells remain unclear. Here, we investigated whether 1,, 25-dihydroxy vitamin D3 (calcitriol) modulated chemokine production in ASM. Experimental approach: Human ASM cell cultures were derived from tracheal samples taken during surgery. ASM cells were treated with tumour necrosis factor alpha (TNF,) and/or interferon gamma (IFN,) for 24 h in the presence of calcitriol and/or the glucocorticoid fluticasone added 2 h before. RANTES (regulated upon activation, normal T-cell expressed and secreted), interferon-inducible protein 10 (IP-10) and fractalkine (FKN) levels in cell supernatants were measured by ELISA. Key results: In TNF,-treated cells, calcitriol inhibited RANTES and IP-10 secretion in a concentration-dependent manner. FKN levels were negligible. In TNF,/IFN,-treated cells, whereas fluticasone or calcitriol alone partially inhibited RANTES secretion (by 38 and 20%, respectively), the combination of both drugs additively inhibited RANTES secretion (by 60%). No effect was observed on IP-10 secretion. Whereas fluticasone enhanced FKN secretion (by 50%), calcitriol significantly decreased FKN levels (by 50%). Interestingly, calcitriol blocked the stimulatory effect of fluticasone on FKN secretion, which was inhibited by 60% with the combination of calcitriol and fluticasone. Conclusions and implications: These findings suggest that vitamin D uniquely modulates human ASM expression of chemokines and may exert some beneficial effects in the treatment of steroid-resistant patients with asthma. British Journal of Pharmacology (2008) 155, 84,92; doi:10.1038/bjp.2008.232; published online 16 June 2008 [source] Mast cell-mediated airway remodellingCLINICAL & EXPERIMENTAL ALLERGY REVIEWS, Issue 4 2006Y. Okayama Summary Airway structural changes (remodelling) in asthma include increased smooth muscle mass, mucus gland hypertrophy, deposition of extracellular matrix components, thickening of reticular basement membrane, and angiogenesis. The extent of remodelling correlates with severity of asthma, and since patients with extensive remodelling may be resistant to steroids therapy, prevention of airway remodelling is a promising therapeutic strategy for curing patients with severe asthma. Mast cells play a pivotal role in allergic inflammatory diseases including asthma and rhinitis. Both early-phase mediators such as tryptase and chymase and late-phase mediators such as cytokines released by mast cells are capable of modulating airway smooth muscle cell function and inducing goblet cell hyperplasia. Nasal remodelling in patients with rhinitis seems far less extensive than that which occurs in bronchi of asthmatic patients. Because cytokine production by smooth muscle cells may partly explain the differences in remodelling at these two sites, further investigation of the interaction between human mast cells and airway smooth muscle cells is required to identify new therapeutic strategies for reducing airway remodelling in asthma. [source] | ||||||||||