Data_Sheet_5_Lactobacillus frumenti Facilitates Intestinal Epithelial Barrier Function Maintenance in Early-Weaned Piglets.XLSX

Increased intestinal epithelial barrier function damages caused by early weaning stress have adverse effects on swine health and feed utilization efficiency. Probiotics have emerged as the promising antibiotic alternatives used for intestinal barrier function damage prevention. Our previous data showed that Lactobacillus frumenti was identified as a predominant Lactobacillus in the intestinal microbiota of weaned piglets. However, whether the intestinal epithelial barrier function in piglets was regulated by L. frumenti is still unclear. Here, piglets received a PBS vehicle or PBS suspension (2 ml, 108 CFU/ml) containing the L. frumenti by oral gavage once a day during the period of 6–20 days of age prior to early weaning. Our data demonstrated that oral administration of L. frumenti significantly improved the intestinal mucosal integrity and decreased the serum endotoxin and D-lactic acid levels in early-weaned piglets (26 days of age). The intestinal tight junction proteins (including ZO-1, Occludin, and Claudin-1) were significantly up-regulated by L. frumenti administration. The serum immunoglobulin G (IgG) levels, intestinal secretory immunoglobulin A (sIgA) levels, and interferon-γ (IFN-γ) levels were significantly increased by L. frumenti administration. Furthermore, our data revealed that oral administration of L. frumenti significantly increased the relative abundances of health-promoting microbes (including L. frumenti, Lactobacillus gasseri LA39, Parabacteroides distasonis, and Kazachstania telluris) and decreased the relative abundances of opportunistic pathogens (including Desulfovibrio desulfuricans and Candida humilis). Functional alteration of the intestinal bacterial community by L. frumenti administration was characterized by the significantly increased fatty acids and protein metabolism and decreased diseases-associated metabolic pathways. These findings suggest that L. frumenti facilitates intestinal epithelial barrier function maintenance in early-weaned piglets and may be a promising antibiotic alternative used for intestinal epithelial barrier function damage prevention in mammals.

早期断奶应激所致的肠道上皮屏障功能损伤，会对猪的健康及饲料利用效率产生负面影响。益生菌作为极具应用前景的抗生素替代品，已被广泛用于肠道屏障功能损伤的预防。本团队前期研究数据显示，谷物乳杆菌(Lactobacillus frumenti)是断奶仔猪肠道微生物群中的优势乳杆菌属菌种。然而，谷物乳杆菌是否可调控仔猪的肠道上皮屏障功能，目前仍不明确。本研究在仔猪6~20日龄（早期断奶前），每日通过灌胃方式给予其磷酸盐缓冲液(PBS)悬液（2 ml，10^8 CFU/ml，含谷物乳杆菌）或空白PBS悬液。研究数据表明，对26日龄早期断奶仔猪灌胃谷物乳杆菌，可显著改善肠道黏膜完整性，并降低血清内毒素与D-乳酸水平。谷物乳杆菌干预可显著上调肠道紧密连接蛋白（包括ZO-1、Occludin及Claudin-1）的表达水平。此外，谷物乳杆菌给药可显著提升仔猪血清免疫球蛋白G(IgG)、肠道分泌型免疫球蛋白A(sIgA)及干扰素-γ(IFN-γ)的含量。进一步研究发现，灌胃谷物乳杆菌可显著增加健康有益菌的相对丰度，包括谷物乳杆菌、加氏乳杆菌LA39(Lactobacillus gasseri LA39)、狄氏副拟杆菌(Parabacteroides distasonis)及哈萨克斯坦酵母(Kazachstania telluris)，同时降低机会致病菌的相对丰度，包括脱硫弧菌(Desulfovibrio desulfuricans)与浅白假丝酵母(Candida humilis)。谷物乳杆菌干预所致的肠道细菌群落功能改变，表现为脂肪酸与蛋白质代谢通路显著富集，而疾病相关代谢通路丰度降低。上述研究结果表明，谷物乳杆菌可维持早期断奶仔猪的肠道上皮屏障功能，有望成为预防哺乳动物肠道上皮屏障功能损伤的潜在抗生素替代品。