Nemeth Edina, Fajdiga Sana, Malago Joshua, Koninkx Jos, Tooten Peter, van Dijk Jaap
Central Food Research Institute, Herman Ottó út 15, H-1022 Budapest, Hungary.
Int J Food Microbiol. 2006 Dec 1;112(3):266-74. doi: 10.1016/j.ijfoodmicro.2006.09.002. Epub 2006 Oct 12.
Oral administration of lactobacilli as probiotics is gaining importance in the treatment of intestinal inflammations. We investigated the effect of non-starter lactobacilli Lactobacillus casei subsp casei 2756, Lactobacillus curvatus 2775, and Lactobacillus plantarum 2142 as well as their spent culture supernatants (SCS) on Salmonella enteritidis 857 growth, interleukin (IL)-8 and heat shock protein 70 (Hsp70) synthesis in undifferentiated crypt-like and differentiated villus-like Caco-2 cells. The cells were infected with graded numbers of non-starter lactobacilli or S. enteritidis 857 for 1 h and allowed to recover for 24 h or exposed to 200 bacteria/cell for 1 h and allowed to recover for different periods of time. In another experiment S. enteritidis 857 was first pre-treated with SCS-lactobacilli for 1 h before infecting the cells. The levels of IL-8 and Hsp70 were assessed using sandwich ELISA and immunostaining of Western blots, respectively. The effect of SCS-lactobacilli on S. enteritidis 857 growth was evaluated by agar plate diffusion test. The non-starter lactobacilli induced a significant increase in the levels of both IL-8 and Hsp70. However, compared with the S. enteritidis 857 induced IL-8 synthesis, the levels of IL-8 induced by the lactobacilli at any equivalent bacterial number were far lower. After exposure of Caco-2 cells to S. enteritidis 857 pre-treated with SCS-lactobacilli, it appeared that their SCS inhibited the S. enteritidis 857 growth and IL-8 synthesis and in addition induced the expression of Hsp70. The differences in response of crypt- and villus-like Caco-2 cells are merely a reflection of their differentiation status. Our data suggest that the beneficial effect of non-starter lactobacilli to the intestinal inflammations might be associated with a decrease of the IL-8 levels. This effect could be mediated, at least in part, by the bacteria themselves or via a secreted antimicrobial product(s) either directly against the pathogens or indirectly through the synthesis of Hsp70.
口服乳酸菌作为益生菌在肠道炎症治疗中的重要性日益凸显。我们研究了非发酵乳酸菌干酪乳杆菌干酪亚种2756、弯曲乳杆菌2775和植物乳杆菌2142及其发酵上清液（SCS）对肠炎沙门氏菌857生长、未分化隐窝样和分化绒毛样Caco-2细胞中白细胞介素（IL）-8和热休克蛋白70（Hsp70）合成的影响。将细胞用不同数量的非发酵乳酸菌或肠炎沙门氏菌857感染1小时，然后恢复24小时，或者以每细胞200个细菌的量暴露1小时，并让其恢复不同的时间段。在另一项实验中，肠炎沙门氏菌857在感染细胞前先用乳酸菌SCS预处理1小时。分别使用夹心ELISA和蛋白质免疫印迹法评估IL-8和Hsp70的水平。通过琼脂平板扩散试验评估乳酸菌SCS对肠炎沙门氏菌857生长的影响。非发酵乳酸菌显著提高了IL-8和Hsp70的水平。然而，与肠炎沙门氏菌857诱导的IL-8合成相比，在任何相同细菌数量下，乳酸菌诱导的IL-8水平要低得多。将Caco-2细胞暴露于用乳酸菌SCS预处理过的肠炎沙门氏菌857后，似乎其SCS抑制了肠炎沙门氏菌857的生长和IL-8合成，此外还诱导了Hsp70的表达。隐窝样和绒毛样Caco-2细胞反应上的差异仅仅反映了它们的分化状态。我们的数据表明，非发酵乳酸菌对肠道炎症的有益作用可能与IL-8水平的降低有关。这种作用至少部分可能是由细菌本身介导的，或者是通过分泌的抗菌产物直接作用于病原体，或者是通过合成Hsp70间接发挥作用。
