MicrocinC7是由大肠杆菌产生的抗菌肽,由七肽和修饰的一磷酸腺苷组成。这项研究是为了评估MicrocinC7作为传统抗生素的潜在底物对生长性能的影响,免疫功能,肠屏障,和肉鸡的盲肠微生物群。在目前的研究中,将300只健康的ArborAcres肉鸡随机分配到五种处理之一,包括玉米大豆基础饮食和补充抗生素或2、4和6mg/kgMicrocinC7的基础饮食。结果表明,MicrocinC7能显著降低肉鸡的F/G比值,显著提高血清细胞因子IL-10、免疫球蛋白IgG和IgM水平,和回肠sIgA分泌;显著降低血清细胞因子TNF-α水平。MicrocinC7可显著提高肉鸡小肠绒毛高度和V/C比值,显著降低隐窝深度。MicrocinC7显著增加紧密连接蛋白Occludin和ZO-1的基因表达,显著降低促炎和趋化因子TNF-α的基因表达,IL-8,IFN-γ,肉鸡空肠中Toll样受体TLR2和TLR4以及下游分子MyD88。MicrocinC7显著增加了肉鸡盲肠中乳酸菌的数量,降低了细菌总数和大肠杆菌的数量。MicrocinC7还显着增加了肉鸡回肠和盲肠中的短链脂肪酸(SCFA)和乳酸水平。总之,添加MicrocinC7的饮食显着提高了生长性能,加强免疫功能,增强肠屏障,和调节肉鸡盲肠微生物群。因此,抗菌肽MicrocinC7可能有潜力成为抗生素的理想替代品。
Microcin C7 is an antimicrobial peptide produced by Escherichia coli, composed of a heptapeptide with a modified adenosine monophosphate. This study was performed to evaluate the effects of Microcin C7 as a potential substrate to traditional antibiotics on growth performance, immune functions, intestinal barrier, and cecal microbiota of broilers. In the current study, 300 healthy Arbor Acres broiler chicks were randomly assigned to one of five treatments including a corn-soybean basal diet and basal diet supplemented with antibiotic or 2, 4, and 6 mg/kg Microcin C7. Results showed that Microcin C7 significantly decreased the F/G ratio of broilers; significantly increased the levels of serum cytokine IL-10, immunoglobulins IgG and IgM, and ileal sIgA secretion; significantly decreased the level of serum cytokine TNF-α. Microcin C7 significantly increased villus height and V/C ratio and significantly decreased crypt depth in small intestine of broilers. Microcin C7 significantly increased gene expression of tight junction protein Occludin and ZO-1 and significantly decreased gene expression of pro-inflammatory and chemokine TNF-α, IL-8, IFN-γ, Toll-like receptors TLR2 and TLR4, and downstream molecular MyD88 in the jejunum of broilers. Microcin C7 significantly increased the number of Lactobacillus and decreased the number of total bacteria and Escherichia coli in the cecum of broilers. Microcin C7 also significantly increased short-chain fatty acid (SCFA) and lactic acid levels in the ileum and cecum of broilers. In conclusion, diet supplemented with Microcin C7 significantly improved growth performance, strengthened immune functions, enhanced intestinal barrier, and regulated cecal microbiota of broilers. Therefore, the antimicrobial peptide Microcin C7 may have the potential to be an ideal alternative to antibiotic.