Wang Zhengxuan, Cai Liang, Li Hui, Liang Mingcai, Zhang Yan, Wu Qiong, Yang Lin
Department of Food Science and Engineering, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, China.
School of Life Science and Biotechnology, Harbin Institute of Technology, Harbin, China.
J Food Biochem. 2020 May;44(5):e13180. doi: 10.1111/jfbc.13180. Epub 2020 Mar 12.
Methionine sulfoxide reductase (Msr) and glutathione (GSH) are two endogenous antioxidant systems for depressing oxidative stress. The aim of this study is to investigate the role of methionine in involving the stimulation of endogenous antioxidant capacity of rice protein (RP). Seven-week-old male Wistar rats (body weight 180-200 g) were fed with commercial pellets (as control), methionine, and RP for 2 weeks. Compared with control, GSH synthesis and expressions of MsrA, MsrB2, and MsrB3 were stimulated by methionine and RP. After 2 weeks of feeding, Nrf2 was activated by RP and methionine, whereas the expressions of Keap1 and Cul3 were depressed. The ARE-driven antioxidant expressions (GCLC, GCLM, GS, HO-1, NQO1, CAT, SOD, GR, GST, GPx) were upregulated by methionine and RP. Results suggest that the endogenous antioxidant response induced by RP is primarily attributed to the methionine availability, in which the stimulation of Msr and GSH antioxidant system via Nrf2-ARE pathway. PRACTICAL APPLICATIONS: Rice protein is a major plant protein, which is rich in sulfur-containing amino acids and widely consumed in the world. This paper emphasizes that the amino acid plays a key role in inducing the antioxidant activity of rice protein. The present study provides an insight that the methionine availability of rice protein will be a useful target for health promoting by activating endogenous antioxidant response against ROS-induced oxidative damage.
甲硫氨酸亚砜还原酶（Msr）和谷胱甘肽（GSH）是两种用于减轻氧化应激的内源性抗氧化系统。本研究的目的是探讨甲硫氨酸在激发大米蛋白（RP）内源性抗氧化能力中的作用。将7周龄雄性Wistar大鼠（体重180 - 200克）分别用市售颗粒饲料（作为对照）、甲硫氨酸和大米蛋白喂养2周。与对照组相比，甲硫氨酸和大米蛋白刺激了GSH的合成以及MsrA、MsrB2和MsrB3的表达。喂养2周后，大米蛋白和甲硫氨酸激活了Nrf2，而Keap1和Cul3的表达受到抑制。甲硫氨酸和大米蛋白上调了ARE驱动的抗氧化剂表达（GCLC、GCLM、GS、HO - 1、NQO1、CAT、SOD、GR、GST、GPx）。结果表明，大米蛋白诱导的内源性抗氧化反应主要归因于甲硫氨酸的可利用性，其中通过Nrf2 - ARE途径刺激了Msr和GSH抗氧化系统。实际应用：大米蛋白是一种主要的植物蛋白，富含含硫氨基酸，在世界范围内广泛食用。本文强调了氨基酸在诱导大米蛋白抗氧化活性中起关键作用。本研究提供了一个见解，即大米蛋白中甲硫氨酸的可利用性将是通过激活针对ROS诱导的氧化损伤的内源性抗氧化反应来促进健康的一个有用靶点。
