Deepa P R, Varalakshmi P
Department of Medical Biochemistry, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani, Chennai 600113, India.
Toxicology. 2006 Jan 16;217(2-3):176-83. doi: 10.1016/j.tox.2005.09.009. Epub 2005 Oct 20.
The spectrum of the anti-apoptotic potential of heparin is currently under scrutiny in various tissues and under various pathological situations. In this study, the role of a low-molecular-weight heparin derivative (LMWH), certoparin in adriamycin-induced oxidative DNA damage has been evaluated in the cardiac and renal tissues. Two groups of male albino rats of the Wistar strain (140+/-10 g) received a single intravenous injection of adriamycin (7.5mg/kg), and one of them received low-molecular-weight heparin (Certoparin Sodium, 300 microg/day/rat s.c.) treatment, commencing on day 8, continued for a week. The nitrosative stress in ADR cytotoxicity is indicated by the 1.51-fold cardiac and 2.36-fold renal increase in reactive nitrogen species (RNS), while LMWH treatment restores normalcy (p<0.001). The influence of LMWH on the pro-inflammatory and pro-apoptotic cytokine, TNF-alpha was studied. Renal and cardiac levels of TNF-alpha showed a significant rise (p<0.001) in the ADR cytotoxic group, while the TNF-alpha values departed towards control levels in the LMWH treated group (p<0.001). DNA damage indicated by the fragmentation pattern (agarose gel electrophoresis) and the significantly increased comet tail length (p<0.001) observed after alkaline single cell gel electrophoresis confirmed the toxicity induced by ADR on DNA in the untreated group. In the LMWH-treated group, the observation of intact DNA band after agarose gel electrophoresis, and the finding of comet tail length being comparable with that of the control substantiated the protection rendered by the LMWH, certoparin. In short, the results suggest that the low-molecular-weight heparin derivative, certoparin exerts beneficial effects on the nitrosative status, and on the biological macromolecules as DNA and curtails the rise of the pro-apoptotic and pro-inflammatory cytokine, TNF-alpha in the cardiac and renal tissues.
目前,肝素的抗凋亡潜能在各种组织和不同病理情况下正受到密切关注。在本研究中,已评估了低分子量肝素衍生物(LMWH)——克赛在阿霉素诱导的心脏和肾脏组织氧化DNA损伤中的作用。两组Wistar品系雄性白化大鼠(140±10克)接受单次静脉注射阿霉素(7.5毫克/千克),其中一组从第8天开始接受低分子量肝素(克赛钠,300微克/天/大鼠皮下注射)治疗,持续一周。阿霉素细胞毒性中的亚硝化应激表现为心脏中活性氮物质(RNS)增加1.51倍,肾脏中增加2.36倍,而低分子量肝素治疗可使其恢复正常(p<0.001)。研究了低分子量肝素对促炎和促凋亡细胞因子肿瘤坏死因子-α(TNF-α)的影响。阿霉素细胞毒性组中肾脏和心脏的TNF-α水平显著升高(p<0.001),而在低分子量肝素治疗组中TNF-α值接近对照组水平(p<0.001)。经碱性单细胞凝胶电泳后观察到的DNA片段化模式以及彗星尾长度显著增加(p<0.001)表明未治疗组中阿霉素对DNA具有毒性。在低分子量肝素治疗组中,琼脂糖凝胶电泳后观察到完整的DNA条带,且彗星尾长度与对照组相当,这证实了克赛这种低分子量肝素所提供的保护作用。简而言之,结果表明低分子量肝素衍生物克赛对亚硝化状态以及DNA等生物大分子具有有益作用,并可抑制心脏和肾脏组织中促凋亡和促炎细胞因子TNF-α的升高。