Peng Sandy, Lin Jin-Yuarn, Lin Meei-Yn
Department of Food Science and Biotechnology, National Chung Hsing University, 250 Kuokuang Road, Taichung 402, Taiwan.
J Agric Food Chem. 2007 Jun 27;55(13):5092-6. doi: 10.1021/jf062869s. Epub 2007 May 27.
The objective of this study was to assess the antiallergic effect of fermented milk prepared, respectively, with Streptococcus thermophilus MC, Lactobacillus acidophilus B, Lactobacillus bulgaricus Lb, L. bulgaricus 448, and Bifidobacterium longum B6. Female BALB/c mice fed fermented milk were immunized intraperitoneally with ovalbumin (OVA)/complete Freund's adjuvant (CFA) to evaluate the immune response by observing the secretion of cytokines IL-2, IL-4, and IFN-gamma and serum antibody IgE. The results showed that supplementation with lactic acid bacteria fermented milk did not significantly change the IL-2 spontaneous and OVA-stimulated secretions of splenocytes. However, both spontaneous and OVA-stimulated secretions of splenocytes from mice fed lactic acid bacteria fermented milk showed significantly (P < 0.05) lower levels of IL-4 (Th2 cytokine) than those from OVA/CFA-immunized mice fed non-fermented milk (OVA/CFA-milk group). The spontaneous secretion of IFN-gamma (Th1 cytokine) by splenocytes from mice fed L. bulgaricus 448 or L. bulgaricus Lb fermented milk significantly increased as compared to that from the OVA/CFA-milk group. The results showed that the ratios of IFN-gamma to IL-4 of both spontaneous and OVA-stimulated secretions in splenocytes from mice fed lactic acid bacteria fermented milk increased significantly as compared to that of PBS- or OVA/CFA-milk groups. The serum levels of OVA-specific IgE in fermented milk fed groups, especially the group fed S. thermophilus MC fermented milk, were significantly lower than those in the OVA/CFA-milk group through a 6 week feeding experiment. The results showed that milk fermented with lactic acid bacteria demonstrated in vivo antiallergic effects on OVA/CFA-immunized mice via increasing the secretion ratio of IFN-gamma/IL-4 (Th1/Th2) by splenocytes and decreasing the serum level of OVA-specific IgE.
本研究的目的是评估分别用嗜热链球菌MC、嗜酸乳杆菌B、保加利亚乳杆菌Lb、保加利亚乳杆菌448和长双歧杆菌B6制备的发酵乳的抗过敏作用。给喂食发酵乳的雌性BALB/c小鼠腹腔注射卵清蛋白（OVA）/完全弗氏佐剂（CFA），通过观察细胞因子IL-2、IL-4和IFN-γ的分泌以及血清抗体IgE来评估免疫反应。结果表明，补充乳酸菌发酵乳并没有显著改变脾细胞IL-2的自发分泌和OVA刺激后的分泌。然而，与喂食未发酵乳的OVA/CFA免疫小鼠（OVA/CFA-乳组）相比，喂食乳酸菌发酵乳的小鼠脾细胞自发分泌和OVA刺激后的分泌中IL-4（Th2细胞因子）水平均显著降低（P<0.05）。与OVA/CFA-乳组相比，喂食保加利亚乳杆菌448或保加利亚乳杆菌Lb发酵乳的小鼠脾细胞自发分泌IFN-γ（Th1细胞因子）显著增加。结果表明，与PBS组或OVA/CFA-乳组相比，喂食乳酸菌发酵乳的小鼠脾细胞自发分泌和OVA刺激后的分泌中IFN-γ与IL-4的比值均显著增加。通过为期6周的喂食实验，发酵乳喂食组，尤其是喂食嗜热链球菌MC发酵乳的组中，OVA特异性IgE的血清水平显著低于OVA/CFA-乳组。结果表明，乳酸菌发酵乳对OVA/CFA免疫小鼠具有体内抗过敏作用，其机制是通过增加脾细胞IFN-γ/IL-4（Th1/Th2）的分泌比值以及降低OVA特异性IgE的血清水平来实现的。
