Pähkla R, Zilmer M, Kullisaar T, Rägo L
Department of Pharmacology, University of Tartu, Estonia.
J Pineal Res. 1998 Mar;24(2):96-101. doi: 10.1111/j.1600-079x.1998.tb00373.x.
Several recent experiments have shown that melatonin is an efficient antioxidant and free radical scavenger. In the present study the antioxidative effect of melatonin was compared with that of pinoline. Pinoline (6-methoxy-tetrahydro-beta-carboline) can be formed in the mammalian body under physiological conditions from 5-hydroxytryptamine or as a tricyclic metabolite of melatonin. Both melatonin and pinoline inhibited lipid peroxidation and showed comparable activity in a total antioxidant status test. Melatonin and pinoline concentration-dependently scavenged hydroxyl radicals with IC50 11.4+/-1.0 microM for melatonin and 62.3+/-3.8 microM for pinoline. These results support the importance of the indolic part of the molecule and the 5-methoxy group common to both compounds in terms of the ability of these molecules to quench the hydroxyl radicals. As pinoline has been shown to exert an antidepressant-like effect in behavioral experiments and has been reported to have a low toxicity, this compound should be further studied as a potential antidepressant with pronounced antioxidative effects. These results further support the importance of pineal gland in antioxidative protection.
最近的几项实验表明，褪黑素是一种有效的抗氧化剂和自由基清除剂。在本研究中，将褪黑素的抗氧化作用与骆驼蓬碱的抗氧化作用进行了比较。骆驼蓬碱（6-甲氧基-四氢-β-咔啉）在生理条件下可在哺乳动物体内由5-羟色胺形成，或作为褪黑素的三环代谢产物形成。褪黑素和骆驼蓬碱均抑制脂质过氧化，并且在总抗氧化状态测试中表现出相当的活性。褪黑素和骆驼蓬碱浓度依赖性地清除羟基自由基，褪黑素的IC50为11.4±1.0微摩尔，骆驼蓬碱的IC50为62.3±3.8微摩尔。这些结果支持了分子中吲哚部分以及两种化合物共有的5-甲氧基在这些分子淬灭羟基自由基能力方面的重要性。由于骆驼蓬碱在行为实验中已显示出类似抗抑郁的作用，并且据报道毒性较低，因此该化合物作为一种具有明显抗氧化作用的潜在抗抑郁药应进一步研究。这些结果进一步支持了松果体在抗氧化保护中的重要性。
