Search

This study was conducted to evaluate the effects of dietary safflower leaf on protective immunity against coccidiosis, the most economically important parasitic disease of poultry. White Leghorn chickens were fed a standard diet with or without safflower leaf and were either uninfected or orally infected with 5,000 sporulated oocysts of Eimeria acervulina. Protective immunity was assessed by body weight gain, fecal oocyst shedding, splenic lymphocytes proliferation, T lymphocyte subpopulations, and proinflammatory cytokine gene expression. We observed that the effect of safflower on experimental coccidiosis was dependant on the dose of the supplement used. A 0.1% (wt/wt) safflower-supplemented diet increased body weight gains of coccidia-infected chickens to a level identical to that of uninfected controls, and significantly reduced fecal oocyst shedding compared with animals that were given a non-supplemented standard diet. Furthermore, increased splenic lymphocyte proliferation as well as greater percentages of CD4+ T cells and decreased CD8+ cells were observed in animals fed a 0.1% safflower-supplemented diet. Finally, IFN-γ, IL-8, IL-15 and IL-17 transcripts in the 0.1% safflower-supplemented group were higher than the non-supplemented controls. These results indicate that safflower leaf when given as a dietary supplement possesses immune-enhancing properties that augment protective immunity against experimental coccidiosis.

A variety of fruits have traditionally been used in Asian cultures to enhance resistance to diseases and treat cancers. However, limited information exists on the underlying mechanisms responsible for these effects. The present investigation was conducted to examine the ability of three Korean indigenous fruits (persimmon, raspberry and tomato) to stimulate lymphocyte proliferation and macrophage nitric oxide production as parameters of innate immunity, and to inhibit tumor cell growth. In vitro co-culture of chicken spleen lymphocytes with methanol extracts of persimmon (Diospyros kaki) or tomato (Lycopersicon esculentum) induced greater cell proliferation compared with cells treated with the vehicle control. Stimulation of chicken macrophages with extracts of persimmon or raspberry (Rubus crataegifolius), but not tomato, stimulated robust nitric oxide production to levels similar to that produced by interferon-γ. All fruit extracts uniformly inhibited the growth chicken tumor cells in vitro. These results provide a rational basis for future studies investigating the effects of medicinal fruits on innate immunity and carcinogenesis in humans and animals.

Safflower (Carthamus tinctorius) has been used as a traditional medicinal plant to enhance natural immunity and treat cancers. However, limited information exists on the mechanisms responsible for its immune enhancing properties. In this study, the immunostimulatory effects of a methanol extract of safflower leaf were assessed by in vitro lymphocyte proliferation, tumor cell cytotoxicity, and nitric oxide production by cultured chicken macrophages. A crude methanol extract of safflower leaf stimulated spleen lymphocyte proliferation and nitric oxide production, and inhibited the viability of tumor cells significantly greater than medium controls. Sequential gel filtration chromatographic separation of the methanol extract on Sephadex G-25 and Sephacryl S-200 columns resulted in a partially purified preparation that retained the ability to induce lymphoproliferation, tumor killing, and NO production. These results demonstrate for the first time that safflower leaf contains immunostimulatory and anti-tumor component(s) that may be potentially useful as a dietary immunomodulator for poultry.