Thioproline Serves as an Efficient Antioxidant Protecting Human Cells from Oxidative Stress and Improves Cell Viability
作者:Yat-Hing Ham、K. K. Jason Chan、Wan Chan
DOI:10.1021/acs.chemrestox.0c00055
日期:2020.7.20
Oxidative stress is associated with the pathophysiology of many degenerative human diseases, including Alzheimer’s disease, atherosclerosis, Parkinson’s disease, and cancers. We discovered in our previous study that thioproline (SPro), a proline analogue, is generated in oxidant-exposed cells. With the prior observation that SPro served as an efficient nitrile trapping agent, we tested in this study the hypothesis that this oxidative stress generated cysteine-formaldehyde adduct, SPro, may serve as an antioxidant protecting cells from oxidative stress. Interestingly, results showed that HeLa cells cultured in SPro-supplemented culture media are more tolerant of oxidative stress, indicated by a dosage-dependent increase in cell viability. Investigation of the molecular mechanism of the observed increase in cell tolerance to oxidative stress revealed SPro acting as an effective antioxidant by sacrificial oxidation. Results also showed that SPro had been incorporated into cellular proteins and induced changes in protein expression profiles of treated cells. Despite being yet to determine the participation of individual factors to the observed increase of cell tolerance to oxidative stress, this study sheds light on the potential use of SPro as a dietary supplement for protecting humans from oxidative stress-associated degenerative human diseases.
氧化应激与许多人类退行性疾病的病理生理学有关,包括阿尔茨海默病、动脉粥样硬化、帕金森病和癌症。我们在之前的研究中发现,脯氨酸类似物硫代脯氨酸(SPro)会在受到氧化作用的细胞中生成。根据之前的观察,SPro 是一种高效的腈捕获剂,因此我们在本研究中测试了这样一种假设,即氧化应激产生的半胱氨酸-甲醛加合物 SPro 可作为一种抗氧化剂保护细胞免受氧化应激。有趣的是,研究结果表明,在添加了 SPro 的培养基中培养的 HeLa 细胞对氧化应激的耐受性更强,这表现在细胞存活率随剂量的增加而增加。对所观察到的细胞对氧化应激耐受性增强的分子机制的研究表明,SPro 通过牺牲氧化作用成为一种有效的抗氧化剂。研究结果还显示,SPro 已被整合到细胞蛋白质中,并诱导处理细胞的蛋白质表达谱发生变化。尽管尚未确定细胞对氧化应激耐受性的提高是由哪些因素引起的,但这项研究揭示了 SPro 作为膳食补充剂保护人类免受与氧化应激相关的人类退化性疾病的潜在用途。