S-CMC-Lys protective effects on human respiratory cells during oxidative stress

Cell Physiol Biochem. 2008;22(5-6):455-64. doi: 10.1159/000185494. Epub 2008 Dec 9.


The mucoactive drug S-carbocysteine lysine salt monohydrate (S-CMC-Lys) stimulates glutathione (GSH) efflux from respiratory cells. Since GSH is one of the most important redox regulatory mechanisms, the aim of this study was to evaluate the S-CMC-Lys effects on GSH efflux and intracellular concentration during an oxidative stress induced by the hydroxyl radical (xOH). Experiments were performed on cultured human respiratory WI-26VA4 cells by means of patch-clamp experiments in whole-cell configuration and of fluorimetric analyses at confocal microscope. xOH exposure induced an irreversible inhibition of the GSH and chloride currents that was prevented if the cells were incubated with S-CMC-Lys. In this instance, the currents were inhibited by the specific blocker CFTR(inh)-172. CFT1-C2 cells, which lack a functional CFTR channel, were not responsive to S-CMC-Lys, but the stimulatory effect of the drug was restored in LCFSN-infected CFT1 cells, functionally corrected to express CFTR. Fluorimetric measurements performed on the S-CMC-Lys-incubated cells revealed a significant increase of the GSH concentration that was completely hindered after oxidative stress and abolished by CFTR(inh)-172. The cellular content of reactive oxygen species was significantly lower in the S-CMC-Lys-treated cells either before or after xOH exposure. As a conclusion, S-CMC-Lys could exert a protective function during oxidative stress, therefore preventing or reducing the ROS-mediated inflammatory response.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbocysteine / analogs & derivatives*
  • Carbocysteine / pharmacology
  • Cell Line
  • Cystic Fibrosis Transmembrane Conductance Regulator / metabolism
  • Cytoprotection / drug effects*
  • Fluorometry
  • Glutathione / metabolism
  • Humans
  • Hydroxyl Radical / metabolism
  • Intracellular Space / drug effects
  • Intracellular Space / metabolism
  • Ion Channel Gating / drug effects
  • Oxidative Stress / drug effects*
  • Protective Agents / pharmacology*
  • Respiratory System / cytology*


  • Protective Agents
  • Cystic Fibrosis Transmembrane Conductance Regulator
  • carbocysteine-lysine
  • Hydroxyl Radical
  • Carbocysteine
  • Glutathione