副干酪乳杆菌N1115发酵乳对小鼠便秘的改善作用

本研究基于盐酸咯哌丁胺建模制造小鼠便秘模型，考察副干酪乳杆菌 N1115发酵乳对治疗小鼠便秘的 作用。低、中、高剂量副干酪乳杆菌N1115发酵乳（活菌含量分别为1×107、1×108、1×109 CFU/mL）连续灌胃 15 d后，与对照组相比小鼠的排便量及粪便含水量均显著升高（P＜0.05）；肠道推进率分别为57.3%、67.3%和 71.3%，显著高于对照组（P＜0.05）。气相色谱仪分析小鼠粪便中的短链脂肪酸发现，灌胃副干酪乳杆菌N1115 发酵乳后，小鼠粪便中的乙酸、丙酸、丁酸、戊酸含量显著升高（P＜0.05），且短链脂肪酸种类较模型组更为丰 富。对小鼠远端结肠的组织形态观察发现，灌胃副干酪乳杆菌N1115发酵乳的小鼠结肠黏膜完整，细胞排列整齐， 而对照组的肠黏膜厚度降低，凹窝变浅。通过c-kit抗体对小鼠结肠中的肠间质细胞（interstitial cells of Cajal，ICC）进 行免疫组化分析，结果显示，灌胃副干酪乳杆菌N1115发酵乳后小鼠的ICC含量显著增加，表明副干酪乳杆菌N1115发 酵乳通过提高ICC活性，促进肠道蠕动。综上，副干酪乳杆菌N1115发酵乳能够有效缓解小鼠的便秘症状。

Therapeutic Effect of Lactobacillus paracasei N1115 Fermented Milk in Constipated Mice

In this study, the therapeutic effect of Lactobacillus paracasei N1115 fermented milk on constipation was examined by using a mouse model of constipation induced by loperamide hydrochloride. After 15 days of feeding with the fermented milk at low (1 × 107 CFU/mL), middle (1 × 108 CFU/mL) and high (1 × 109 CFU/mL) dosages, the constipated mice had a significant increase in defecation and fecal moisture content (P < 0.05) as well as increased intestinal propulsion rates of 57.3%, 67.3% and 71.3%, respectively, when compared with the control group (P < 0.05). Analysis of short chain fatty acids in feces by gas chromatography-mass spectrometry showed significantly increased contents of acetic acid, propionic acid, butyric acid and valeric acid in the treated mice (P < 0.05) along with more diverse short chain fatty acids than compared with the control mice. Histological analysis of distal colon tissue showed that the colon mucosa of the treated mice remained intact with orderly cell arrangement, while that of the model control mice was reduced in thickness with shallower pits. Furthermore, immunohistochemical analysis of interstitial cells of Cajal (ICC) in colon tissue using c-kit antibody showed that feeding constipated mice with the fermented milk significantly increased colonic ICC, indicating increased ICC activity and intestinal movement. These results showed that L. paracasei N1115 fermented milk had a positive therapeutic effect on constipation.