Gadde Ujvala Deepthi, Oh Sungtaek, Lee Youngsub, Davis Ellen, Zimmerman Noah, Rehberger Tom, Lillehoj Hyun Soon
Animal Biosciences and Biotechnology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, USDA, Beltsville, MD 20705, USA.
Agro Biosciences Inc., 10437 Innovation Drive, Wauwatosa, WI 53226, USA.
Res Vet Sci. 2017 Oct;114:236-243. doi: 10.1016/j.rvsc.2017.05.004. Epub 2017 May 6.
This study investigated the effects of Bacillus subtilis-based probiotics on the performance, modulation of host inflammatory responses and intestinal barrier gene expression of broilers subjected to LPS challenge. Chickens were randomly allocated to one of the 3 dietary treatment groups - control, antibiotic, or probiotic. At 14days, half of the chickens in each treatment were injected with LPS (1mg/kg body weight), and the other half injected with sterile PBS. Chickens fed probiotics weighed significantly more than controls at 15days of age, irrespective of immune challenge. LPS challenge significantly reduced weight gain at 24h post-injection, and the probiotics did not alleviate the LPS-induced reduction of weight gain. Serum α-1-AGP levels were significantly higher in LPS-injected chickens, and probiotic supplementation significantly reduced their levels. The percentages of CD4+ lymphocytes were significantly increased in probiotic groups in the absence of immunological challenge but were reduced during LPS challenge compared to controls. CD8+ lymphocytes were significantly reduced in probiotic-fed birds. The LPS-induced increase in the expression of cytokines IL8 and TNFSF15 was reduced by probiotic supplementation, and IL17F, iNOS expression was found to be significantly elevated in probiotic-fed birds subjected to LPS challenge. The reduced gene expression of tight junction proteins (JAM2, occludin and ZO1) and MUC2 induced by LPS challenge was reversed by probiotic supplementation. The results indicate that B. subtilis-based probiotics differentially regulate intestinal immune and tight junction protein mRNA expression during states of LPS-mediated immunological challenge.
本研究调查了基于枯草芽孢杆菌的益生菌对遭受脂多糖（LPS）攻击的肉鸡的生产性能、宿主炎症反应调节及肠道屏障基因表达的影响。将鸡随机分配到3个日粮处理组之一——对照组、抗生素组或益生菌组。在14日龄时，每个处理组的一半鸡注射LPS（1mg/kg体重），另一半注射无菌磷酸盐缓冲盐水（PBS）。无论免疫攻击情况如何，饲喂益生菌的鸡在15日龄时体重显著高于对照组。LPS攻击显著降低了注射后24小时的体重增加，且益生菌并未减轻LPS诱导的体重增加减少。注射LPS的鸡血清α-1-抗胰蛋白酶（α-1-AGP）水平显著更高，补充益生菌显著降低了其水平。在无免疫攻击时，益生菌组CD4+淋巴细胞百分比显著增加，但与对照组相比，在LPS攻击期间降低。饲喂益生菌的鸡CD8+淋巴细胞显著减少。补充益生菌降低了LPS诱导的细胞因子IL8和肿瘤坏死因子配体超家族成员15（TNFSF15）表达增加，且发现遭受LPS攻击的饲喂益生菌的鸡IL17F、诱导型一氧化氮合酶（iNOS）表达显著升高。补充益生菌逆转了LPS攻击诱导的紧密连接蛋白（连接粘附分子2（JAM2）、闭合蛋白和紧密连接蛋白1（ZO1））和黏蛋白2（MUC2）基因表达降低。结果表明，基于枯草芽孢杆菌的益生菌在LPS介导的免疫攻击状态下差异调节肠道免疫和紧密连接蛋白mRNA表达。
