Tian Xinyu, Zhang Zeru, Zhao Yuquan, Tang Anguo, Zeng Zhi, Zheng Weijian, Zhang Hanwen, Luo Yuxin, Lu Wei, Fan Lei, Shen Liuhong
The Key Laboratory of Animal Disease and Human Health of Sichuan Province, The Medical Research Center for Cow Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China.
College of Veterinary Medicine, Jiangsu Agri-Animal Husbandry Vocational College, Taizhou 225300, China.
Antioxidants (Basel). 2024 Jul 29;13(8):913. doi: 10.3390/antiox13080913.
Our preliminary study identified dairy cow placenta extract (CPE) as a mixture of peptides with potent antioxidant activity both in vivo and in vitro. However, the specific antioxidant peptides (AOPs) responsible for this activity were not yet identified. In the current study, we employed virtual screening and chromatography techniques to isolate two peptides, ANNGKQWAEVF (CP1) and QPGLPGPAG (CP2), from CPE. These peptides were found to be less stable under extreme conditions such as high temperature, strong acid, strong alkali, and simulated digestive conditions. Nevertheless, under normal physiological conditions, both CP1 and CP2 exhibited significant antioxidant properties, including free-radical scavenging, metal chelating, and the inhibition of lipid peroxidation. They also up-regulated the activities of intracellular antioxidant enzymes in response to hydrogen-peroxide-induced oxidative stress, resulting in reduced MDA levels, a decreased expression of the Keap1 gene and protein, and increased levels of the Nrf2 and HO-1 genes and proteins. Furthermore, CP1 demonstrated superior antioxidant activity compared to CP2. These findings suggest that CP1 and CP2 hold potential for mitigating oxidative stress in vitro and highlight the efficacy of virtual screening as a method for isolating AOPs within CPE.
我们的初步研究确定，奶牛胎盘提取物（CPE）是一种在体内和体外均具有强大抗氧化活性的肽混合物。然而，尚未确定负责这种活性的特定抗氧化肽（AOP）。在当前研究中，我们采用虚拟筛选和色谱技术从CPE中分离出两种肽，即ANNGKQWAEVF（CP1）和QPGLPGPAG（CP2）。发现这些肽在高温、强酸、强碱和模拟消化条件等极端条件下不太稳定。然而，在正常生理条件下，CP1和CP2均表现出显著的抗氧化特性，包括自由基清除、金属螯合和脂质过氧化抑制。它们还在过氧化氢诱导的氧化应激反应中上调细胞内抗氧化酶的活性，导致丙二醛（MDA）水平降低、Keap1基因和蛋白表达减少，以及Nrf2和HO-1基因和蛋白水平升高。此外，CP1表现出比CP2更强的抗氧化活性。这些发现表明，CP1和CP2在体外减轻氧化应激方面具有潜力，并突出了虚拟筛选作为一种从CPE中分离AOP的方法的有效性。
