College of Biological Science and Technology, Fuzhou University, Fuzhou, Fujian 355300, China.
Zhongshi Beishan (Fujian)Wine Co., Ltd., Zherong, Fujian 350108, China.
J Agric Food Chem. 2020 Nov 4;68(44):12259-12270. doi: 10.1021/acs.jafc.0c04353. Epub 2020 Oct 21.
In this study, a bioactive peptide YGPSSYGYG (YG-9) with immunomodulatory activity was isolated and identified from protein hydrolysate. The highest proliferation index of mouse spleen lymphocytes reached 1.19 in the presence of 50 μg/mL YG-9. YG-9 could activate RAW264.7 cells by promoting the secretions of NO, the pinocytosis activity, and the productions of ROS and TNF-α. Moreover, YG-9 enhanced the expressions of TLR2 and TLR4 in RAW264.7 cells. TNF-α secretions induced by YG-9 were reduced in TLR2 and TLR4 siRNAs knockdown cells, and this suggested that macrophage activation of YG-9 was through TLR2 and TLR4. Furthermore, YG-9 promoted the translocation of NF-κB through the acceleration of IκB-α phosphorylation and degradation. Also, TNF-α secretions promoted by YG-9 were inhibited by NF-κB-specific inhibitors pyrrolidine dithiocarbamate and BAY11-7082. Altogether, these results suggested YG-9 activated RAW264.7 cells via the TLRs/NF-κB/TNF-α signaling pathway.
在这项研究中，从蛋白质水解物中分离并鉴定出一种具有免疫调节活性的生物活性肽 YGPSSYGYG（YG-9）。在 50μg/mL YG-9 的存在下，小鼠脾淋巴细胞的最高增殖指数达到 1.19。YG-9 通过促进 NO 的分泌、吞噬作用、ROS 和 TNF-α 的产生来激活 RAW264.7 细胞。此外，YG-9 增强了 RAW264.7 细胞中 TLR2 和 TLR4 的表达。在 TLR2 和 TLR4 siRNAs 敲低细胞中，YG-9 诱导的 TNF-α 分泌减少，这表明 YG-9 对巨噬细胞的激活是通过 TLR2 和 TLR4 实现的。此外，YG-9 通过加速 IκB-α 的磷酸化和降解促进 NF-κB 的易位。同样，NF-κB 特异性抑制剂吡咯烷二硫代氨基甲酸盐和 BAY11-7082 抑制了 YG-9 诱导的 TNF-α 分泌。总的来说，这些结果表明 YG-9 通过 TLRs/NF-κB/TNF-α 信号通路激活 RAW264.7 细胞。
