• Priscilla C Olsen, Luciana P Coelho, Jorge C S da Costa, Renato S B Cordeiro, Patricia M R Silva, and Marco A Martins.
• Laboratory of Inflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, RJ, Brazil.
• Eur. J. Pharmacol. 2012 Apr 5; 680 (1-3): 102-7.

AbstractInhalation of JMF2-1, an analog of lidocaine with reduced anesthetic activity, prevents airway contraction and lung inflammation in experimental asthma models. We sought to test if the JMF2-1 effects are a consequence of increased intracellular cAMP levels in asthma cell targets, such as smooth muscle cells and T cells. Functional effect of JMF2-1 on carbachol-induced contraction of intact or epithelial-denuded rat trachea was assessed in conventional organ baths. cAMP was quantified by radioimmunoassay in cultured guinea pig tracheal smooth muscle cells, as well as lymph node cells from BALB/c mice, exposed to JMF2-1. We found that JMF2-1 (0.1-1mM) concentration-dependently inhibited epithelium-intact tracheal ring contraction induced by carbachol challenge. The antispasmodic effect remained unaltered following epithelium removal or pretreatment with NG-nitro-L-arginine methyl ester (100μM), but it was clearly sensitive to 9-(tetrahydro-2-furyl) adenine (SQ22,536, 100μM), an adenylate cyclase inhibitor. JMF2-1 (300 and 600μM) also dose-dependently increased cAMP intracellular levels of both cultured airway smooth muscle cells and T lymphocytes. This effect was consistently abrogated by SQ22,536 and reproduced by forskolin in both systems. JMF2-1 induced apoptosis of anti-CD3 activated T cells in a mechanism sensitive to zIETD, indicating that JMF2-1 mediates caspase-8-dependent apoptosis. Furthermore, forskolin also inhibited anti-CD3 induced T cell proliferation and survival. Our results suggest that JMF2-1 inhibits respiratory smooth muscle contraction as well as T cell proliferation and survival through enhancement of intracellular cAMP levels. These findings may help to explain the anti-inflammatory and antispasmodic effects of JMF2-1 observed in previous studies.Copyright © 2012 Elsevier B.V. All rights reserved.

60 keywords...

hide…