Prophylactic Effectiveness of Propolis for lmmunostimulation: A Clinical Pilot lnvestigation
Abstract: Objective: The aim of this pilot investigation was to show the evidence of the prophylactic immunostimulating effectiveness caused by propolis. The immune response was determined by the measurement of the cytokine level in vivo and ex vivo (TNFa, IL-6, IL-8). Study Design: In an open prospective monocentric study, test persons received Propolis XNP Patients: 10 healthy test persons aged between 18 and 45 years, with normal weight and of either sex. Interventions: Probands received over 13 days 500 mg Propolis XNP (2 capsules) for peroral application in the morning. Main Outcome Measures: Significant changes of the investigated cytokine secretion capacity during and after the treatment of propolis compared to the situation without medication. Results: Although the cytokine plasma levels did not significantly change during the study, propolis led to a significant increase of both the spontaneous (TNFa, p < 0.05; IL-6, p < 0.01; IL-8, p < 0.02; IL-1ß, not detectable) and LPS(lipopolysaccaride)-induced (TNF-a, p < 0.001; IL-6, p < 0.02; IL-8, p < 0.0005; IL-1ß, p < 0.05) cytokine secretion capacity following short-term ex vivo culture of peripheral blood leukocytes. Whereas the IL-6 secretion capacity further increased during the 13-day application, the IL-8 and TNF-a secretion reached a plateau after day 4 and the TNF-a secretion even decreased, but the level at day 13 was still significantly higher than at day 0. Conclusion: As the cytokine secretion capacity but not the cytokine plasma levels increased significantly during therapy, the prophylactic application of propolis led to a time dependent enhanced immune reactivity without undesired side effects.