The Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical Universitygrid.440588.5, Xi'an, Shaanxi, China.
Appl Environ Microbiol. 2021 Nov 10;87(23):e0163621. doi: 10.1128/AEM.01636-21. Epub 2021 Sep 15.
Composite microecological agents have received widespread attention due to their advantageous properties, including safety, multiple effects, and low cost. This study was conducted to evaluate the protective effects of selenium (Se) nanoparticle (SeNP)-enriched Lactococcus lactis NZ9000 (L. lactis NZ9000-SeNPs) against enterotoxigenic Escherichia coli (ETEC) K88-induced intestinal barrier damage in C57BL/6 mice. The oral administration of L. lactis NZ9000-SeNPs significantly increased the villus height and the number of goblet cells in the ileum; reduced the levels of serum and ileal interleukin-1β (IL-1β), tumor necrosis factor alpha (TNF-α), and interferon gamma (IFN-γ); and increased the activities of thioredoxin reductase (TrxR) and glutathione peroxidase (GSH-Px) compared with the ETEC K88-infected group not treated with L. lactis NZ9000-SeNPs. In addition, L. lactis NZ9000-SeNPs significantly attenuated the reduction of the expression levels of occludin and claudin-1, dysbiosis of the gut microbiome, and activation of the Toll-like receptor (TLR)/nuclear factor kappa B (NF-κB)-mediated signaling pathway induced by ETEC K88. These findings suggested that L. lactis NZ9000-SeNPs may be a promising and safe Se supplement for food or feed additives. The beneficial effects of microecological agents have been widely proven. Se, which is a nutritionally essential trace element for humans and animals, is incorporated into selenoproteins that have a wide range of pleiotropic effects, ranging from antioxidant to anti-inflammatory effects. However, sodium selenite, a common addition form of Se in feed and food, has disadvantages such as strong toxicity and low bioavailability. We investigated the protective effects of L. lactis NZ9000-SeNPs against ETEC K88-induced intestinal barrier injury in C57BL/6 mice. Our results show that L. lactis NZ9000-SeNPs effectively alleviate ETEC K88-induced intestinal barrier dysfunction. This study highlights the importance of developing a promising and safe Se supplement for the substitution of sodium selenite applied in food, feed, and biomedicine.
复合微生物制剂因其安全性、多效性和低成本等优势而受到广泛关注。本研究旨在评估富硒纳米颗粒（SeNP）乳球菌（Lactococcus lactis NZ9000）（L. lactis NZ9000-SeNPs）对肠产毒性大肠杆菌（ETEC）K88 诱导的 C57BL/6 小鼠肠道屏障损伤的保护作用。口服 L. lactis NZ9000-SeNPs 可显著增加回肠的绒毛高度和杯状细胞数量；降低血清和回肠白细胞介素-1β（IL-1β）、肿瘤坏死因子-α（TNF-α）和干扰素-γ（IFN-γ）水平；并增加硫氧还蛋白还原酶（TrxR）和谷胱甘肽过氧化物酶（GSH-Px）的活性，与未用 L. lactis NZ9000-SeNPs 治疗的 ETEC K88 感染组相比。此外，L. lactis NZ9000-SeNPs 可显著减轻 ETEC K88 引起的紧密连接蛋白和闭合蛋白-1 表达水平降低、肠道微生物组失调以及 Toll 样受体（TLR）/核因子 kappa B（NF-κB）介导的信号通路激活。这些发现表明，L. lactis NZ9000-SeNPs 可能是一种有前途和安全的硒补充剂，可作为食品或饲料添加剂。微生物制剂的有益作用已得到广泛证实。硒是人和动物必需的营养微量元素，它被纳入具有广泛的多效性的硒蛋白中，从抗氧化作用到抗炎作用。然而，亚硒酸钠是饲料和食品中常用的硒添加形式，具有毒性强、生物利用度低等缺点。我们研究了 L. lactis NZ9000-SeNPs 对 C57BL/6 小鼠肠产毒性大肠杆菌 K88 诱导的肠道屏障损伤的保护作用。我们的结果表明，L. lactis NZ9000-SeNPs 可有效缓解 ETEC K88 诱导的肠道屏障功能障碍。本研究强调了开发一种有前途和安全的硒补充剂替代饲料、食品和生物医药中应用的亚硒酸钠的重要性。
