College of Food Science and Engineering/Collaborative Innovation Center for Modern Grain Circulation and Safety/Key Laboratory of Grains and Oils Quality Control and Processing, Nanjing University of Finance and Economics, Nanjing 210023, China.
Food Funct. 2018 Jul 17;9(7):3764-3775. doi: 10.1039/c8fo00604k.
Pleurotus eryngii contains bioactive compounds that can activate the immune system. Here we report the identification, purification, and functional characterization of the bioactive P. eryngii protein (PEP) 1b. PEP 1b was discovered to be a 21.9 kDa protein with the ability to induce the M1-polarization of the macrophage cell line RAW 264.7 cells. Biochemical measurements showed that PEP 1b stimulated nitric oxide (NO), IL-1β, IL-6 and TNF-α production and regulated inducible NO synthase. Phosphorylation and inhibitor studies revealed that PEP 1b promoted the translocation of NF-kB from the cytosol to the nucleus allowing the induction of target gene expression and NO production. The phosphorylation of JNK and ERK1/2 was found to be necessary for NO production. Each phosphorylation pathway was found to require a Toll-like receptor (TLR) 4 as a prerequisite for PEP 1b-induced NO production. This study suggests that PEP 1b is an immunomodulatory protein that can boost cellular immune responses through the activation of the TLR4-NF-κB and MAPK signaling pathways.
杏鲍菇含有能激活免疫系统的生物活性化合物。在这里，我们报告了生物活性杏鲍菇蛋白（PEP）1b 的鉴定、纯化和功能特征。发现 PEP 1b 是一种 21.9 kDa 的蛋白质，能够诱导巨噬细胞系 RAW 264.7 细胞向 M1 极化。生化测量表明，PEP 1b 刺激一氧化氮（NO）、IL-1β、IL-6 和 TNF-α 的产生，并调节诱导型一氧化氮合酶。磷酸化和抑制剂研究表明，PEP 1b 促进 NF-κB 从细胞质向细胞核易位，从而诱导靶基因表达和 NO 的产生。发现 JNK 和 ERK1/2 的磷酸化对于 NO 的产生是必需的。发现每个磷酸化途径都需要 Toll 样受体（TLR）4 作为 PEP 1b 诱导的 NO 产生的前提条件。这项研究表明，PEP 1b 是一种免疫调节蛋白，通过激活 TLR4-NF-κB 和 MAPK 信号通路，增强细胞免疫反应。
