[The effects of erythromycin on the secretion of tumor necrosis factor-alpha and transforming growth factor-beta1 and expression of connexin 43 in human pleural mesothelial cells].

OBJECTIVES:To investigate the effects of erythromycin on secretion of tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta(1) (TGF-beta(1)), and the level of connexin 43 in human pleural mesothelial cells (HPMC), and to explore the mechanism of pleurodesis. METHODS:HPMC was incubated with erythromycin at concentrations of 100 mg/L or 25 mg/L. The levels of TNF-alpha and TGF-beta(1) in the supernatants were measured by ELISA method, and levels of connexin 43 were detected by Western blot. RESULTS:The secretion of TNF-alpha by HMPC increased after incubation with 100 mg/L erythromycin for 3 or 5 days, and the secretion of TGF-beta(1) increased markedly after incubation with lower or higher concentrations of erythromycin. The levels of connexin 43 in HPMC decreased after stimulation with 100 mg/L erythromycin, but no relationship was observed between the levels and the stimulation time. CONCLUSIONS:HPMC incubated with erythromycin showed increased secretion of TNF-alpha and TGF-beta(1), which may be one of the mechanisms for erythromycin pleurodesis. Erythromycin decreased the level of connexin 43 in HPMC, and this effect may be a response of the cells to the stimulus. A high concentration of erythromycin is suggested for clinical pleurodesis based on the results from this study.