Journal of Clinical and Experimental Investigations

Abstract

Objectives: Propolis, a bee-product, has attracted researchers’ interest in recent years because of several biological and pharmacological properties. Lipopolysaccharide (LPS) is a component of the outer membrane of Gram-negative bacteria and has an important role in the pathogenesis of septic shock and several inflammatory diseases by causing excessive release of inflammatory cytokines. The aim of this study was to investigate the effects of ethanol extract of propolis collected in Kayseri and its surroundings on production of pro-inflammatory cytokines in LPS-stimulated macrophages.
Materials and methods: In vitro, U937 human macrophage cells were grown in RPMI-1640 medium supplemented with fetal bovine serum (10%) and penicillin-streptomycin (2%) and divided into: control, LPS treated, and propolis+LPS treated cell groups. After incubation in an atmosphere of 5% CO₂ and at 37°C of cells, interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α levels were measured in cell-free supernatants by ELISA.
Results: IL-1β, IL-6 and TNF-α levels increased in LPS treated cell group according to control, statistically significant. Each cytokine levels significantly decreased in LPS and propolis treated cell group according to only LPS treated cell group (p<0.05).
Conclusion: Propolis is a natural product to be examined for usage when needed the suppression of pro-inflammatory cytokines.