Maccarrone M, Veldink G A, Vliegenthart J F, finnazzi Agrò A
IDI-IRCCS Unit, University of Rome Tor Vergata, Italy.
Lipids. 1995 Jan;30(1):51-4. doi: 10.1007/BF02537041.
The aim of this investigation was to determine whether chain-breaking antioxidants able to prevent lipid peroxidation can inhibit lipoxygenase-1 (EC 1.13.11.12). Therefore, the effects of ascorbic acid, 6-palmitoylascorbic acid and trolox on the enzyme activity were analyzed by means of Lineweaver-Burk double reciprocal plots and Yoshino's graphical method. The effect of these compounds on the formation of free radicals during lipoxygenase-1 reaction was investigated as well, by monitoring the enzymic formation of oxodienes. We present evidence that the chain-breaking antioxidants ascorbic acid, 6-palmitoylascorbic acid and trolox inhibit soybean lipoxygenase-1 in the micromolar concentration range (Ki 27, 3 and 18 microM, respectively). The inhibition is competitive, complete and reversible. All three compounds trap the free radicals formed during the lipoxygenase-catalyzed reaction, which might substantially contribute to their inhibitory ability. These findings can have physiological significance in the light of the lipoxygenase involvement in biomembrane remodelling.
本研究的目的是确定能够防止脂质过氧化的断链抗氧化剂是否能抑制脂氧合酶-1（EC 1.13.11.12）。因此，通过Lineweaver-Burk双倒数作图法和吉野氏图解法分析了抗坏血酸、6-棕榈酰抗坏血酸和生育酚对该酶活性的影响。通过监测氧二烯的酶促形成，还研究了这些化合物对脂氧合酶-1反应过程中自由基形成的影响。我们提供的证据表明，断链抗氧化剂抗坏血酸、6-棕榈酰抗坏血酸和生育酚在微摩尔浓度范围内抑制大豆脂氧合酶-1（抑制常数Ki分别为27、3和18微摩尔）。这种抑制是竞争性的、完全的且可逆的。所有这三种化合物都能捕获脂氧合酶催化反应过程中形成的自由基，这可能极大地有助于它们的抑制能力。鉴于脂氧合酶参与生物膜重塑，这些发现可能具有生理学意义。
