Faria Ana, Monteiro Rosário, Mateus Nuno, Azevedo Isabel, Calhau Conceição
Dept. of Biochemistry (U38-FCT), Faculty of Medicine, University of Porto, Al. Prof. Hernâni Monteiro, 4200-319, Porto, Portugal.
Eur J Nutr. 2007 Aug;46(5):271-8. doi: 10.1007/s00394-007-0661-z. Epub 2007 May 18.
Pomegranate juice (PJ) possesses a high antioxidant activity, which has been related to beneficial health properties. However, in vivo confirmation and characterization of these effects on biological systems are lacking and needed. This study was performed in order to investigate the effect of prolonged PJ ingestion on general oxidation status. For this purpose, mice ingested PJ (or water in control group) during four weeks, after which damage to lipids, proteins and DNA were evaluated as oxidative cell biomarkers. Levels of hepatic glutathione and the activities and expression of enzymes involved in its metabolism were determined. Catalase and SOD activities were quantified as these enzymes have a crucial role in antioxidant defence. Protection against protein and DNA oxidation was found in PJ group. There was also a significant decrease in GSH and GSSG, without change in the GSH/GSSG ratio. All studied enzymatic activities (GPx, GST, GR, SOD and catalase) were found to be decreased by PJ treatment. Additionally, RT-PCR results showed that GST and GS transcription were also decreased in this group. These results are compatible with a protective effect of PJ against systemic oxidative stress in mice.
石榴汁（PJ）具有很高的抗氧化活性，这与有益健康的特性相关。然而，目前缺乏对这些作用在生物系统中的体内验证和特性描述，这是需要进行研究的。本研究旨在调查长期摄入PJ对总体氧化状态的影响。为此，小鼠在四周内摄入PJ（对照组摄入水），之后将脂质、蛋白质和DNA的损伤作为氧化细胞生物标志物进行评估。测定肝脏谷胱甘肽水平及其代谢相关酶的活性和表达。对过氧化氢酶和超氧化物歧化酶的活性进行了定量，因为这些酶在抗氧化防御中起关键作用。在PJ组中发现了对蛋白质和DNA氧化的保护作用。谷胱甘肽（GSH）和氧化型谷胱甘肽（GSSG）也显著降低，而GSH/GSSG比值没有变化。发现PJ处理会降低所有研究的酶活性（谷胱甘肽过氧化物酶、谷胱甘肽S-转移酶、谷胱甘肽还原酶、超氧化物歧化酶和过氧化氢酶）。此外，逆转录聚合酶链反应（RT-PCR）结果表明，该组中谷胱甘肽S-转移酶和谷胱甘肽合成酶的转录也降低。这些结果与PJ对小鼠全身氧化应激的保护作用相符。
