Journal of Ethnopharmacology 100 (2005) 276–283 Effects of ethanol and water extracts of propolis (bee glue) on acute inflammatory animal models Fuliang Hu a , H.R. Hepburn b,∗ , Yinghua Li a , M. Chen c , S.E. Radloff d , S. Daya e a College of Animal Science, Zhejiang University, Hangzhou 310029, China b Department of Zoology and Entomology, Rhodes University, Grahamstown 6140, South Africa c Zhejiang College of Traditional Chinese Medicine, Hangzhou 310053, China d Department of Statistics, Rhodes University, Grahamstown 6140, South Africa e Department of Pharmacology, Rhodes University, Grahamstown 6140, South Africa Received 27 November 2003; received in revised form 19 November 2004; accepted 28 February 2005 Available online 17 May 2005 Abstract The anti-inflammatory effects of ethanol (EEP) and water (WSD) extracts in ICR mice and Wistar rats were analyzed. Both WSD and EEP exhibited significant anti-inflammatory effects in animal models with respect to thoracic capillary vessel leakage in mice, carrageenan- induced oedema, carrageenan-induced pleurisy, acute lung damage in rats. The mechanisms for the anti-inflammatory effects probably involve decreasing prostaglandin-E 2 (PGE 2 ) and nitric oxide (NO) levels. In rats with Freund’s complete adjuvant (FCA) induced arthritis, propolis extracts significantly inhibited the increase of interleukin-6 (IL-6) in inflamed tissues, but had no significant effect on levels of interleukin-2 (IL-2) and interferon- (IFN-). The results are consistent with the interpretation that EEP and WSD may exert these effects by inhibiting the activation and differentiation of mononuclear macrophages. © 2005 Elsevier Ireland Ltd. All rights reserved. Keywords: Propolis; Freund’s complete adjuvant induced arthritis; Anti-inflammatory effects 1. Introduction Propolis is a resinous material that honeybees (Apis mellif- era L.) collect from various plant species and mix with wax and other substances. The chemical composition of propo- lis includes flavonoids, aromatic acids and esters, aldehy- des and ketones, fatty acids and esters, terpenes, steroids, amino acids, polysaccharides, hydrocarbons, alcohols, hy- droxybenzene and several other compounds in trace amounts (Bankova et al., 1983, 2000; Marcucci, 1995). Propolis has been particularly widely used in the medical and chemical in- dustries of China because of its extensive antibacterial, anti- inflammatory and immuno-regulatory properties (Wang et al., 1993; Marcucci, 1995; Marcucci et al., 2001; Banskota ∗ Corresponding author. Tel.: +27 46 6038098; fax: +27 46 6222723. E-mail address: r.hepburn@ru.ac.za (H.R. Hepburn). et al., 2002). Propolis has low water solubility and studies on such derivatives are few indeed. The anticomplementary activity of propolis in vitro and complementary activity in vivo have been documented (Ivanovska et al., 1995a). However, previous results indi- cate that the action of water-soluble derivatives (WSD) de- pends on the route of WSD administration and not on rela- tive differences in the effects of WSD and ethanol extracted derivatives (EEP). In the experiments reported here, anti- inflammatory effects of ethanol (EEP) and water (WSD) ex- tracts in ICR mice and Wistar rats were analyzed with respect to thoracic capillary vessel leakage in mice, carrageenan- induced oedema, carrageenan-induced pleurisy, acute lung damage and Freund’s complete adjuvant (FCA) induced arthritis. The model is also sensitive to anti-inflammatory and immune-inhibiting medicines (Ivanovska et al., 1995a, 1995b). 0378-8741/$ – see front matter © 2005 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.jep.2005.02.044