Anti-inflammatory activity of probiotic Bifidobacterium: Enhancement of IL-10 production in peripheral blood mononuclear cells from ulcerative colitis patients and inhibition of IL-8 secretion in HT-29 cells

Figure 1 Effects of probiotic bifidobacteria on IL-10 production in PBMNC. PBMNC were isolated from 9 ulcerative-colitis patients and incubated with heat-killed probiotic BbiY or BbrY (10 &mgr;g/mL), or LPS. At forty-eight hours after incubation, the IL-10 concentration was determined by ELISA (mean ± SD, n = 3). ^aP < 0.05, ^bP < 0.01 vs BbiY; ^cP < 0.05, ^dP < 0.01 LPS.

Figure 2 Effects of probiotic bifidobacteria on IL-8 production in HT-29 cells. HT-29 cells were stimulated with TNF-α (10 ng/mL) in the absence or presence of various concentrations of probiotic bacteria. Six hours after incubation, the IL-8 concentration was determined by ELISA (mean ± SD, n = 4).

Figure 3 Effects of probiotic bifidobacteria-derived CMs on IL-8 production in HT-29 cells. HT-29 cells were stimulated with TNF-α in the absence or presence of graded dilutions of CMs. CMs were prepared as described in the Methods. Other experimental conditions are shown in Figure 2. ^aP < 0.05, ^bP < 0.01 vs control.

Figure 4 Assessment of the molecular weight of active component in probiotic-derived CMs. CM was separated into fractions of more than and less than 3 kDa, adjusted to the initial volume. The inhibitory effect on the secretion of IL-8 was determined as described in Figure 2. ^bP < 0.01 vs control.

Figure 5 Effects of acetic acid and/or lactic acid on IL-8 secretion in HT-29 cells. HT-29 cells were incubated with approximately the same concentration of acetic acid (11 mmol/L) and/or lactic acid (4 mmol/L) to that of CMs. The inhibitory effect on the secretion of IL-8 was determined as described in Figure 2. ^aP < 0.05, ^bP < 0.01 vs control.

Figure 6 IL-8 and IκB-ζ mRNA expression during the culture of HT-29 cells in the presence of probitic-derived CMs. The mRNA expression was quantified as described in Materials and Methods. Results are representative of three separate experiments.

Figure 7 Effects of probiotic DNAs on IL-8 production in HT-29 cells. HT-29 cells were stimulated with TNF-α in the absence or presence of various concentrations of probiotic DNA without (A) or with DNase treatment (B). The inhibitory effect on IL-8 secretion was determined as described in Figure 2. ^aP < 0.05, ^bP < 0.01 vs control.