Enhanced production of IL-2 from anti-CD3 antibody-stimulated mouse spleen cells by caffeic acid phenethyl ester, a major component of Chinese propolis.

OBJECTIVES: We evaluated the immune-modulatory effects of Chinese propolis (CP) and its major constituent, caffeic acid phenethyl ester (CAPE), on the cytokine production of anti-CD3 antibody-stimulated mouse spleen cells. METHODS: Mouse spleen cells stimulated by anti-CD3 monoclonal antibody were co-cultured with CP, CAPE, and HC030031, a specific antagonist of the TRPA1 Ca2+-permeable cation channel. Cytokine production was assayed by enzyme-linked immunosorbent assay. Interleukin (IL)-2 mRNA expression was examined by reverse transcription-quantitative polymerase chain reaction. RESULTS: In stimulated spleen cells treated with 1/16,000 CP diluent, IL-2 production was markedly enhanced, while IL-4 and IL-10 productions were not significantly affected. In contrast, interferon (IFN)-γ, IL-6, and IL-17 productions were markedly reduced. These effects of CP were reproduced by the CAPE treatment. A time-course observation demonstrated that, compared to control cells, IL-2 mRNA expression and production were significantly enhanced in the spleen cells stimulated by CAPE; however, IL-2 production was markedly delayed compared to that in the untreated control cells. The enhancement of IL-2 production by CAPE was scarcely alleviated by the addition of HC030031. These effects of CAPE upon IL-2 mRNA production were abolished in spleen cells without anti-CD3 antibody stimulation. CONCLUSIONS: CAPE is an important regulator of CP for cytokine regulation in anti-CD3 antibody-stimulated spleen cells. The agent specifically reduced IFN-γ, IL-6, and IL-17 and slightly enhanced Th2 cytokine production while significantly enhancing IL-2 production at the transcriptional level.

Amelioration of Osteoarthritis Development by Daily Oral Supplementation of Royal Jelly.

Royal jelly (RJ), an essential food for the queen honeybee, has a variety of biological activities. Although RJ exerts preventive effects on various lifestyle-related diseases, such as osteoporosis and obesity, no study evaluated the effect of RJ on the development of osteoarthritis (OA), the most common degenerative joint disease. Here, we showed that daily oral administration of raw RJ significantly prevented OA development in vivo following surgically-induced knee joint instability in mice. Furthermore, in vitro experiments using chondrocytes, revealed that raw RJ significantly reduced the expression of inflammatory cytokines and enzymes critical for the degradation of the extracellular matrix (ECM). Similar results were observed after treatment with 10-hydroxy-2-decenoic acid, the most abundant and unique fatty acid in raw RJ. Our results suggest that oral supplementation with RJ would benefit the maintenance of joint health and prophylaxis against OA, possibly by suppressing the activity of inflammatory cytokines and ECM-degrading enzymes.

Enhanced production of IL-2 from anti-CD3 antibody-stimulated mouse spleen cells by artepillin C, a major component of Brazilian green propolis.

OBJECTIVES: In this report, we attempt to clarify the immune modulatory effects of Brazilian green propolis (BGP) and its major component, artepillin C, on the cytokine production of anti-CD3 antibody-stimulated mouse spleen cells. We also estimate the physiological mechanism affecting artepillin C's upon the cells. METHODS: Male C3H/HeN mouse spleen cells stimulated by antiCD3 monoclonal antibody were co-cultured with BGP, artepillin C, and HC030031, a transient receptor potential ankyrin 1 (TRPA1) Ca2+ channel antagonist. The synthesis of interferon (IFN)-γ, interleukin (IL)-6, IL-17, IL-4, IL-10, and IL-2 was assayed by enzyme-linked immunoassay. The expression of IL-2 mRNA and the protein product were examined by reverse transcription-quantitative polymerase chain reaction and Western blot analyses, respectively. RESULTS: The production of IL-2 was markedly enhanced, while that of IL-4 and IL-10 was not significantly affected; by contrast, the production of IFN-γ, IL-6, and IL-17 was significantly reduced in the antibody-stimulated spleen cells treated with BGP at a non-cytostatic concentration. These effects were reproduced in the cells treated with artepillin C. The expression of IL-2 mRNA was unaffected; however, that of the protein was significantly enhanced in the artepillin C-treated cells compared to untreated control cells. The enhancement of protein expression and the production of IL-2 by artepillin C was significantly alleviated by adding HC030031. CONCLUSIONS: Artepillin C is an important regulator of cytokine synthesis from activated spleen cells. The agent specifically augmented the expression of IL-2 via the Ca2+-permeable cation channel, TRPA1, at least in part, at the translational or secretion levels.