Prunus cerasoides fruit extract ameliorates inflammatory stress by modulation of iNOS pathway and Th1/Th2 immune homeostasis in activated murine macrophages and lymphocytes.

The present investigation assessed the potential of Prunus cerasoides fruit extract (PCFE) in alleviation of inflammatory stress in response to lipopolysaccharide (LPS) and interferon-γ (IFN-γ)-stimulated murine peritoneal macrophages as well as in concanavalin A (Con A)-activated splenic lymphocytes. We observed a strong inhibition in production of nitric oxide (NO), reactive oxygen species (ROS), inflammatory cytokines (TNF-α/IL-6/IL-1β), inducible nitric oxide synthase (iNOS), and NF-kB in macrophages treated with PCFE. Splenic lymphocytes treated with PCFE also showed a reduction in Con-A-induced cell proliferation and numbers of CD3+CD4+ T cells. Furthermore, PCFE treatment to Con A-stimulated lymphocytes decreased the production of inflammatory cytokines (TNF-α/IL-6/IL-1β) with a concomitant increase in IL-10 suggesting its possible role in alleviation of inflammation-driven Th1/Th2 immune imbalance. PCFE appeared to influence innate immune response even at lower concentrations (25 and 50 µg/ml), while such effects were more pronounced in lymphocytes only at higher concentrations (100 and 200 µg/ml). UPLC-ESI-MS of PCFE revealed the presence of major bioactive phenolics including catechin, naringin as well as ascorbic acid which could have contributed in above findings. Overall, it is indicative that P. cerasoides fruit could be a valuable source for the development of anti-inflammatory functional foods and nutraceuticals.