Jeong Jin Boo, Hong Se Chul, Jeong Hyung Jin
College of Natural Sciences, Andong National University, Andong, Republic of Korea.
Phytomedicine. 2009 Jan;16(1):85-94. doi: 10.1016/j.phymed.2008.09.013. Epub 2008 Nov 20.
Barley is a major crop worldwide. It has been reported that barley seeds have an effect on scavenging ROS. However, little has been known about the functional role of the barley on the inhibition of DNA damage and apoptosis by ROS. In this study, we purified 3,4-dihydroxybenzaldehyde from the barley with silica gel column chromatography and HPLC and then identified it by GC/MS. And we firstly investigated the inhibitory effects of 3,4-dihydroxybenzaldehyde purified from the barley on oxidative DNA damage and apoptosis induced by H(2)O(2), the major mediator of oxidative stress and a potent mutagen. In antioxidant activity assay such as DPPH radical and hydroxyl radical scavenging assay, Fe(2+) chelating assay, and intracellular ROS scavenging assay by DCF-DA, 3,4-dihydroxybenzaldehyde was found to scavenge DPPH radical, hydroxyl radical and intracellular ROS. Also it chelated Fe(2+). In in vitro oxidative DNA damage assay and the expression level of phospho-H2A.X, it inhibited oxidative DNA damage and its treatment decreased the expression level of phospho-H2A.X. And in oxidative cell death and apoptosis assay via MTT assay and Hoechst 33342 staining, respectively, the treatment of 3,4-dihydroxybenzaldehyde attenuated H(2)O(2)-induced cell death and apoptosis. These results suggest that the barley may exert the inhibitory effect on H(2)O(2)-induced tumor development by blocking H(2)O(2)-induced oxidative DNA damage, cell death and apoptosis.
大麦是全球主要作物。据报道，大麦种子具有清除活性氧（ROS）的作用。然而，关于大麦在抑制ROS诱导的DNA损伤和细胞凋亡方面的功能作用，人们了解甚少。在本研究中，我们通过硅胶柱色谱和高效液相色谱（HPLC）从大麦中纯化出3,4 - 二羟基苯甲醛，然后用气相色谱/质谱联用仪（GC/MS）对其进行鉴定。并且我们首次研究了从大麦中纯化得到的3,4 - 二羟基苯甲醛对由H₂O₂诱导的氧化DNA损伤和细胞凋亡的抑制作用，H₂O₂是氧化应激的主要介质和一种强效诱变剂。在抗氧化活性测定中，如1,1 - 二苯基 - 2 - 苦基肼（DPPH）自由基清除测定、羟基自由基清除测定、Fe²⁺螯合测定以及通过2',7'-二氯二氢荧光素二乙酸酯（DCF - DA）进行的细胞内ROS清除测定，发现3,4 - 二羟基苯甲醛能够清除DPPH自由基、羟基自由基和细胞内ROS。它还能螯合Fe²⁺。在体外氧化DNA损伤测定以及磷酸化组蛋白H2A.X的表达水平测定中，它抑制了氧化DNA损伤，并且其处理降低了磷酸化组蛋白H2A.X的表达水平。在分别通过噻唑蓝（MTT）测定和Hoechst 33342染色进行的氧化细胞死亡和细胞凋亡测定中，3,4 - 二羟基苯甲醛的处理减轻了H₂O₂诱导的细胞死亡和细胞凋亡。这些结果表明，大麦可能通过阻断H₂O₂诱导的氧化DNA损伤、细胞死亡和细胞凋亡，对H₂O₂诱导的肿瘤发展发挥抑制作用。
