Effects of Oral Administration of Yam Tuber Storage Protein, Dioscorin, to BALB/c Mice for 21-Days on Immune Responses

Abstract

Dioscorin, the tuber storage protein of yam, was reported to have immunomodulatory activity in RAW264.7 murine macrophage cell lines ( Food and Chemical Toxicology , 2007 , 45 , 2312 -2318 ). However, the immunomodulatory function of dioscorin after being ingested was not elucidated in vivo. Hence, BALB/c mice were given oral dioscorin (2.5 and 20 mg/kg/day) once a day for 21-days. Lymphocyte subpopulation changes in the peripheral blood and splenocytes, stimulation in phagocytosis of the polymorphonuclear cell (PMN) and monocytes, the natural killer (NK) cell cytotoxicity, the splenocyte proliferation, and cytokine secretions in the presence of PHA were determined. The number changes of Peyer's patches and secreted IgA (sIgA) in the feces were determined. Oral dioscorin for 21-days increased the subpopulation in natural killer cells (CD49(+)) and/or B cells (CD19(+)), elevated the phagocytosis of PMN (p < 0.01) and MON (p < 0.01), and the NK cell cytotoxic activity (p < 0.05), and stimulated splenocyte proliferations in the presence of LPS or PHA (p < 0.05) in comparison with those of the control. Cytokines of INF-gamma, IL-4, and IL-10 secretions, the numbers of Peyer's patches, and sIgA in the feces showed higher levels in oral dioscorin and significant difference to those of the control (p < 0.001). These results suggested that dioscorin exhibited systemic and mucosal immunomodulatory activities after being ingested in vivo.

Oral administration of Lactobacillus plantarum K68 ameliorates DSS-induced ulcerative colitis in BALB/c mice via the anti-inflammatory and immunomodulatory activities

“…Human peripheral blood mononuclear cells (hPBMCs) were isolated from healthy volunteers as described previously [16] with slight modifications. The hPBMCs were collected and resuspended in RPMI 1640 medium containing 10% FBS, 100 IU/ml penicillin, 0.1 mg/ml streptomycin, 0.25 μg/ml amphotericin, and 1% L-glutamate.…”

Immunomodulatory Activity ofLactococcus lactisA17 from Taiwan Fermented Cabbage in OVA-Sensitized BALB/c Mice

“…Based on a previous report [21] with slight modifications, hPBMCs were isolated from healthy volunteers with no history of atopic disease. In brief, hPBMCs were isolated by centrifugation at 1,500 rpm for 20 min using Ficoll (GE, Uppsala, Sweden).…”

Class A dioscorins of various yam species suppress ovalbumin-induced allergic reactions

“…Moreover, Da-dioscorins enhanced the phagocytic activity of the RAW264.7 macrophage against Escherichia coli and stimulated the proliferation of murine splenocytes 11,13 . Oral administrating Da-dioscorins to BALB/c mice stimulated splenocytes to secrete IFN-g, IL-4 and IL-10, increased the subpopulation in NK and B cells and the number of Peyer's patches 14 . Da-dioscorins and dioscorins from Dioscorea japonica (designated as Dj-dioscorins) were reported to protect the expression of tight junction proteins from dust mite damage in human airway epithelial cells 15 .…”