The effect of propolis on pro-inflammatory cytokines produced by melanoma-bearing mice submitted to chronic stress.
Fabiane Missima, Ana C. Pagliarone, Cláudio L. Orsatti, José M. Sforcin
Altered levels of pro-inflammatory cytokines could be prometastatic and proangiogenic factors. Stress leads to somatic disorders such as cancer, and animal models have been used to investigate stress effects on tumorigenesis and immune response modulation. Propolis is a honeybee product and its immunomodulatory effects on stressed mice have been the goal of our recent researches. In this work, propolis effect on pro-inflammatory (IL-1β and IL-6) cytokines production by melanoma-bearing mice submitted to immobilization stress were analysed. Propolis administration to stressed mice inhibited pro-inflammatory cytokines production. On the other hand, propolis induced higher levels of IL-1β and IL-6 in melanoma-bearing mice submitted or not to chronic stress. Since propolis also stimulated Th1 cytokines production in these mice, one may speculate that a synergistic effect of IFN-γ and pro-inflammatory cytokines could inhibit tumour growth in vivo by inducing the production of antiangiogenic factors. Further investigation will help to understand propolis usefulness during stress.