Yeo JuDong, Shahidi Fereidoon
Department of Biochemistry, Memorial University of Newfoundland, St. John's, Newfoundland A1B 3X9, Canada.
J Agric Food Chem. 2021 Apr 14;69(14):4204-4209. doi: 10.1021/acs.jafc.0c08088. Epub 2021 Apr 1.
The oxidation of human low-density-lipoprotein (LDL) particles is responsible for the development of cardiovascular diseases (CVDs). In the present study, the occurrence of riboflavin-sensitized photooxidation of LDL particles was examined in an system. The presence of light, oxygen, and photosensitizer (50 μM riboflavin) caused the riboflavin-sensitized photooxidation of human LDL particles thereby increasing in the conjugated dienes (CDs) by 32.5 ± 4.8% ( < 0.05), indicating that this could serve as a major culprit in the development of CVDs. A 1 h radiation caused a 63.6 ± 0.3% degradation of the riboflavin content, and this indicates the extremely fast reaction of the riboflavin-sensitized photooxidation. The singlet oxygen quenching capacity of β-carotene was determined at three different concentrations (10, 50, and 100 μM), exhibiting both antioxidant and prooxidant effects, depending on the concentrations used. In addition, ascorbic acid displayed a high incorporation rate into the LDL particles, implying its potential in preventing riboflavin photosensitization of LDL particles. To the best of our knowledge, this is the first report on the riboflavin-sensitized photooxidation of LDL particles in an system, proposing a new possible mechanism in the development of CVDs.
人低密度脂蛋白（LDL）颗粒的氧化是心血管疾病（CVDs）发生的原因。在本研究中，在一个体系中检测了LDL颗粒的核黄素敏化光氧化的发生情况。光、氧和光敏剂（50μM核黄素）的存在导致人LDL颗粒发生核黄素敏化光氧化，从而使共轭二烯（CDs）增加32.5±4.8%（P<0.05），表明这可能是CVDs发生的主要原因。1小时的辐射导致核黄素含量降解63.6±0.3%，这表明核黄素敏化光氧化反应极快。在三种不同浓度（10、50和100μM）下测定了β-胡萝卜素的单线态氧猝灭能力，其表现出抗氧化和促氧化作用，这取决于所使用的浓度。此外，抗坏血酸在LDL颗粒中的掺入率很高，这意味着它在预防LDL颗粒的核黄素光敏化方面具有潜力。据我们所知，这是关于在一个体系中LDL颗粒的核黄素敏化光氧化的首次报道，提出了CVDs发生的一种新的可能机制。
