Influence of cinnamic acid on lymphocyte proliferation, cytokine release and Klebsiella infection in mice

Abstract - The effect of a complex of propolis constituents, cinnamic acid and L-lysine, on host defence mechanisms was investigated. After intraperitoneal (ip) application of cinnamic acid lysine complex (CN·Ly) to mice at a dose of 3 mg/kg for 3 consecutive days prior to inoculation with Klebsiella pneumoniae, a protective effect was observed. The action of CN·Ly was associated with its ability to provoke proliferation of thymic and splenic lymphocytes and to augment mitogen-induced proliferation, and the release of interleukin-1 (IL-1) and interleukin-2 (IL-2). In all experiments, a solution of L-lysine in a concentration equivalent to the lysine content in the complex was used for comparison. The results indicated that free lysine acted in a mitogen-like manner predominantly on T-lymphocytes. In the complex, lysine played the role of a carrier and exhibited a less pronounced effect.