Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy.
Molecules. 2023 Sep 14;28(18):6629. doi: 10.3390/molecules28186629.
Oxidative stress results from an imbalance between reactive oxygen species (ROS) production and the body's ability to neutralize them. ROS are reactive molecules generated during cellular metabolism and play a crucial role in normal physiological processes. However, excessive ROS production can lead to oxidative damage, contributing to various diseases and aging. This study is focused on rosmarinic acid (RA), a hydroxycinnamic acid (HCA) derivative well known for its antioxidant activity. In addition, RA has also demonstrated prooxidant behavior under specific conditions involving high concentrations of transition metal ions such as iron and copper, high pH, and the presence of oxygen. In this study, we aim to clarify the underlying mechanisms and factors governing the antioxidant and prooxidant activities of RA, and to compare them with other HCA derivatives. UV-Vis, NMR, and EPR techniques were used to explore copper(II)'s binding ability of RA, caffeic acid, and p-coumaric acid. At the same time, UV-Vis and NMR methods were exploited to evaluate the polyphenols' free radical scavenging abilities towards ROS generated by the ascorbic acid-copper(II) system. All the data indicate that RA is the most effective polyphenol both in copper binding abilities and ROS protection.
氧化应激是由于活性氧（ROS）的产生与机体清除它们的能力之间失衡所致。ROS 是细胞代谢过程中产生的具有反应活性的分子，在正常生理过程中起着至关重要的作用。然而，过量的 ROS 产生会导致氧化损伤，从而导致各种疾病和衰老。本研究聚焦于迷迭香酸（RA），这是一种众所周知的具有抗氧化活性的羟基肉桂酸（HCA）衍生物。此外，RA 在涉及高浓度过渡金属离子（如铁和铜）、高 pH 值和氧气存在的特定条件下也表现出促氧化行为。在本研究中，我们旨在阐明控制 RA 的抗氧化和促氧化活性的潜在机制和因素，并将其与其他 HCA 衍生物进行比较。使用 UV-Vis、NMR 和 EPR 技术来探究 RA、咖啡酸和对香豆酸与铜（II）的结合能力。同时，利用 UV-Vis 和 NMR 方法评估多酚类化合物对抗坏血酸-铜（II）系统产生的 ROS 的自由基清除能力。所有数据均表明，RA 在铜结合能力和 ROS 保护方面都是最有效的多酚之一。
