Analysis Note: The protein was determined by the biuret method.
Application: The soybean enzyme will use arachidonic acid as a substrate, with approximately 15% of its activity indicated using linoleic acid. The product of arachidonic acid oxidation is either 12-hydroperoxyarachidonic acid (12-HPETE) or 15-hydroperoxyarachidonic acid (15-HPETE).
Biochemical/Physiological Actions: This enzyme catalyzes the hydroperoxidation of lipids containing a cis,cis-1,4-pentadiene structure.
Unit Definition: One unit will cause an increase in A234 of 0.001 per minute at pH 9.0 and 25°C when linoleic acid is the substrate in a 3.0 ml volume (1 cm light path). One A234 unit is equivalent to the oxidation of 0.12 μmole of linoleic acid.
Physical Form: The product contains stabilizers and NaCl.
脂氧合酶(LOX)是参与白三烯和活性氧自由基生物合成的关键酶,与炎症性疾病的病理生理学有关。本研究旨在评估水溶性抗氧化剂抗坏血酸及其亲脂性衍生物抗坏血酸6-棕榈酸酯(Vcpal)对体外多形核淋巴细胞5-LOX和大豆15-LOX(sLOX)的抑制作用。
通过分光光度法和高效液相色谱法测定LOX活性,测量5-羟过氧基二十碳四烯酸(5-HETE)和脂质过氧化物的产物。进行基质依赖型酶动力学和对接研究,以了解抑制的性质。
与对sLOX的抑制效果相比,Vcpal强力抑制5-LOX(IC50分别为2.5和10.3μm,P=0.003)。此外,Vcpal比已知的合成药物苯哌酮和诺地醌酸(P=0.0007)更强烈地抑制5-LOX。酶动力学研究表明Vcpal是5-LOX的非竞争性可逆抑制剂。体外分子对接显示,相较于抗坏血酸,Vcpal具有较高的MolDock和Rerank分数,与体内结果相互印证。
体外和对接研究均表明Vcpal而不是抗坏血酸是5-LOX和sLOX诱导的脂质过氧化的非竞争性抑制剂,提示亲脂性质在抑制过程中起关键作用。