The β-adrenoceptor agonist clenbuterol is a potent inhibitor of the LPS-induced production of TNF-α and IL-6 in vitro and in vivo

Abstract:

Objective and Design: To investigate the suppressive effects of the β-agonist clenbuterol on the release of TNF-α and IL-6 in a lipopolysaccharide (LPS)-model of inflammation, both in vitro and in vivo.¶Material and Subjects: Human U-937 cell line (monocyte-derived macrophages), and male Wistar rats (200-250g).¶Treatment: U-937 macrophages were incubated with LPS at 1 μg/ml, with or without 1.0mM-0.1nM test drugs (clenbuterol and other cAMP elevating agents) for 1-24h. Rats were administered either 1 or 10 μg/kg clenbuterol (or saline) orally, 1h before intraperitoneal administration of 2mg/kg LPS.¶Methods and Results: TNF-α and IL-6 time-concentration profiles were determined both in culture media and plasma, using ELISA' s and bioassays. LPS-mediated release of both cytokines was significantly suppressed by clenbuterol.¶Conclusions: The β-agonist clenbuterol very potently suppresses the LPS-induced release of the pro-inflammatory cytokines TNF-α and IL-6 both in vitro and in vivo.