Wei Xubiao, Zhang Lulu, Zhang Rijun, Wu Rujuan, Si Dayong, Ahmad Baseer, Petitte James N, Mozdziak Paul E, Li Zhongxuan, Guo Henan, Zhang Manyi
State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, China.
College of Agriculture and Life Sciences, North Carolina State University, Raleigh, NC, USA.
FASEB J. 2020 Dec;34(12):16049-16072. doi: 10.1096/fj.201903263RRR. Epub 2020 Oct 15.
Intestinal inflammatory disorders, such as inflammatory bowel disease, are major contributors to mortality and morbidity in humans and animals worldwide. While some native peptides have great potential as therapeutic agents against intestinal inflammation, potential cytotoxicity, anti-inciting action, and suppression of anti-inflammatory activity may limit their development as anti-inflammatory agents. Peptide hybridization is an effective approach for the design and engineering of novel functional peptides because hybrid peptides combine the advantages and benefits of various native peptides. In the present study, a novel hybrid anti-inflammatory peptide that combines the active center of Cecropin A (C) and the core functional region of LL-37 (L) was designed [C-L peptide; C (1-8)-L (17-30)] through in silico analysis to reduce cytotoxicity and improve the anti-inflammatory activity of the parental peptides. The resulting C-L peptide exhibited lower cytotoxicity than either C or L peptides alone. C-L also exerted a protective effect against lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 macrophages and in the intestines of a mouse model. The hybrid peptide exhibited increased anti-inflammatory activity compared to the parental peptides. C-L plays a role in protecting intestinal tissue from damage, LPS-induced weight loss, and leukocyte infiltration. In addition, C-L reduces the expression levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), IL-1β, and interferon-gamma (IFN-γ), as well as reduces cell apoptosis. It also reduced mucosal barrier damage caused by LPS. The anti-inflammatory effects of the hybrid peptide were mainly attributed to its LPS-neutralizing activity and antagonizing the activation of LPS-induced Toll-like receptor 4-myeloid differentiation factor 2 (TLR4/MD2). The peptide also affected the TLR4-(nuclear factor κB) signaling pathway, modulating the inflammatory response upon LPS stimulation. Collectively, these findings suggest that the newly designed peptide, C-L, could be developed into a novel anti-inflammatory agent for animals or humans.
肠道炎症性疾病，如炎症性肠病，是全球人类和动物死亡和发病的主要原因。虽然一些天然肽作为抗肠道炎症的治疗剂具有很大潜力，但潜在的细胞毒性、抗刺激作用和抗炎活性抑制可能会限制它们作为抗炎剂的开发。肽杂交是设计和工程新型功能肽的有效方法，因为杂交肽结合了各种天然肽的优点。在本研究中，通过计算机分析设计了一种新型杂交抗炎肽，它结合了天蚕素A（C）的活性中心和LL-37（L）的核心功能区域 [C-L肽；C (1-8)-L (17-30)]，以降低细胞毒性并提高亲本肽的抗炎活性。所得的C-L肽比单独的C或L肽表现出更低的细胞毒性。C-L还对RAW264.7巨噬细胞和小鼠模型肠道中脂多糖（LPS）诱导的炎症反应发挥保护作用。与亲本肽相比，杂交肽表现出增强的抗炎活性。C-L在保护肠道组织免受损伤、LPS诱导的体重减轻和白细胞浸润方面发挥作用。此外，C-L降低肿瘤坏死因子-α（TNF-α）、白细胞介素-6（IL-6）、IL-1β和干扰素-γ（IFN-γ）的表达水平，并减少细胞凋亡。它还减少了LPS引起的黏膜屏障损伤。杂交肽的抗炎作用主要归因于其LPS中和活性以及拮抗LPS诱导的Toll样受体4-髓样分化因子2（TLR4/MD2）的激活。该肽还影响TLR4-（核因子κB）信号通路，调节LPS刺激后的炎症反应。总的来说，这些发现表明新设计的肽C-L可开发成为一种用于动物或人类的新型抗炎剂。
