Protective Effects of Rice Peptide Oryza Peptide-P60 against Oxidative Injury through Activation of Nrf2 Signaling Pathway In Vitro and In Vivo
Protective Effects of Rice Peptide Oryza Peptide-P60 against Oxidative Injury through Activation of Nrf2 Signaling Pathway In Vitro and In Vivo
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DOI：
10.1021/acsomega.0c01016
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发表时间：
2020-06-09
期刊：
影响因子：
4.1
通讯作者：
Tsuboi, Seiji
中科院分区：
文献类型：
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作者：
Moritani, Chie;Kawakami, Kayoko;Tsuboi, Seiji
我们先前表明，市售的大米肽Oryza肽-P60（OP 60）增加细胞内谷胱甘肽水平。本研究旨在评估这种肽的抗氧化潜力并评估其作用机制。用OP 60预处理HepG 2细胞通过恢复谷胱甘肽稳态降低了H2 O2或对乙酰氨基酚（APAP）引起的细胞毒性（与H2 O2或APAP处理组相比，5 mg/mL OP 60预处理组的细胞毒性分别为47.7 +/- 1.3%或12.2 +/- 1.3%; p < 0.01）。此外，OP 60在8 h时使编码γ-谷氨酰半胱氨酸合成酶（γ-GCS）重亚基和轻亚基的基因的mRNA水平分别提高了2.9 +/- 0.1倍和2.7 +/- 0.2倍（p < 0.001），并且还提高了编码其他抗氧化酶的mRNA水平。此外，在8h后，OP 60促进Nrf 2核转位2.2 ± 0.3倍（p < 0.05）。相反，Nrf 2的敲低抑制了细胞内谷胱甘肽水平的增加，并抑制了OP 60对抗氧化酶表达的诱导。在动物研究中，OP 60通过抑制谷胱甘肽耗竭（从0.19 +/- 0.02 mmol/mg蛋白质降至0.90 +/- 0.02 mmol/mg蛋白质; p < 0.01，通过500 mg/kg OP 60预处理）和增加肝脏中γ-GCS重亚基和血红素加氧酶-1的表达来预防APAP诱导的肝损伤。我们的研究结果表明，OP 60通过Nrf 2信号通路表现出细胞保护作用，是少数具有优异抗氧化特性的肽之一。
We previously showed that commercially available rice peptide Oryza Peptide-P60 (OP60) increased the intracellular glutathione levels. This study aimed to evaluate the antioxidant potential of this peptide and assess its mechanism of action. Pretreatment of HepG2 cells with OP60 reduced the cytotoxicity caused by H2O2 or acetaminophen (APAP) (47.7 +/- 1.3% or 12.2 +/- 1.3% of the cytotoxicity for 5 mg/mL OP60 pretreatment compared to that in H2O2- or APAP-treated groups, respectively; p < 0.01) through the restoration of glutathione homeostasis. Moreover, OP60 elevated the mRNA level of genes encoding heavy and light subunits of gamma-glutamylcysteine synthetase (gamma-GCS) by 2.9 +/- 0.1-fold and 2.7 +/- 0.2-fold (p < 0.001), respectively, at 8 h and also increased the level of mRNA encoding other antioxidant enzymes. Besides, OP60 promoted Nrf2 nuclear translocation by 2.2 +/- 0.3-fold (p < 0.05) after 8 h. Conversely, knockdown of Nrf2 inhibited the increase of the intracellular glutathione levels and suppressed the induction of antioxidant enzyme expression by OP60. In animal studies, OP60 prevented APAP-induced liver injury by suppressing glutathione depletion (from 0.19 +/- 0.02 mmol/mg protein to 0.90 +/- 0.02 mmol/mg protein; p < 0.01, by pretreatment with 500 mg/kg OP60) and increasing heavy subunit of gamma-GCS and heme oxygenase-1 expression in the liver. Our results indicated that OP60 exhibits a cytoprotective effect via the Nrf2 signaling pathway and is one of the few peptides with excellent antioxidant properties.