Xu Feiran, Wang Lifeng, Ju Xingrong, Zhang Jing, Yin Shi, Shi Jiayi, He Rong, Yuan Qiang
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, P.R. China.
J Agric Food Chem. 2017 Mar 15;65(10):2056-2065. doi: 10.1021/acs.jafc.6b04731. Epub 2017 Mar 3.
Studies on antioxidant peptides extracted from foodstuff sources have included not only experiments to elucidate their chemical characteristics but also to investigate their bioavailability and intracellular mechanisms. This study was designed to clarify the absorption and antioxidative activity of YWDHNNPQIR (named RAP), which is derived from rapeseed protein using a Caco-2 cell transwell model. Results showed that 0.8% RAP (C = 0.2 mM, t = 90 min) could maintain the original structure across the Caco-2 cell monolayers via the intracellular transcytosis pathway, and the apparent drug absorption rate (P) was (6.6 ± 1.24) × 10 cm/s. Three main fragments (WDHNNPQIR, DHNNPQIR, and YWDHNNPQ) and five modified peptides derived from RAP were found in both the apical and basolateral side of the Caco-2 cell transwell model. Among these new metabolites, WDHNNPQIR had the greatest antioxidative activity in Caco-2 cells apart from the DPPH assay. With a RAP concentration of 200 μM, there were significant differences in four antioxidative indicators (T-AOC, GSH-Px, SOD, and MDA) compared to the oxidative stress control (P < 0.05). In addition, RAP may also influence apoptosis of the Caco-2 cells, which was caused by AAPH-induced oxidative damage.
对从食品来源提取的抗氧化肽的研究不仅包括阐明其化学特性的实验，还包括研究其生物利用度和细胞内机制。本研究旨在使用Caco-2细胞transwell模型阐明源自菜籽蛋白的YWDHNNPQIR（命名为RAP）的吸收和抗氧化活性。结果表明，0.8%的RAP（C = 0.2 mM，t = 90分钟）可通过细胞内转胞吞途径在Caco-2细胞单层中维持原始结构，表观药物吸收率（P）为（6.6 ± 1.24）× 10 cm/s。在Caco-2细胞transwell模型的顶端和基底外侧均发现了三个主要片段（WDHNNPQIR、DHNNPQIR和YWDHNNPQ）以及源自RAP的五个修饰肽。在这些新代谢产物中，除DPPH测定外，WDHNNPQIR在Caco-2细胞中具有最大的抗氧化活性。当RAP浓度为200 μM时，与氧化应激对照组相比，四个抗氧化指标（T-AOC、GSH-Px、SOD和MDA）存在显著差异（P < 0.05）。此外，RAP还可能影响由AAPH诱导的氧化损伤引起的Caco-2细胞凋亡。
