Calabrese Vittorio, Ravagna Agrippino, Colombrita Claudia, Scapagnini Giovanni, Guagliano Eleonora, Calvani Menotti, Butterfield D Allan, Giuffrida Stella Anna Maria
Department of Chemistry, Biochemistry and Molecular Biology Section, Faculty of Medicine, University of Catania, Catania, Italy.
J Neurosci Res. 2005 Feb 15;79(4):509-21. doi: 10.1002/jnr.20386.
Efficient functioning of maintenance and repair processes seem to be crucial for both survival and physical quality of life. This is accomplished by a complex network of the so-called longevity assurance processes, under control of several genes termed vitagenes. These include members of the heat shock protein system, and there is now evidence that the heat shock response contributes to establishing a cytoprotective state in a wide variety of human conditions, including inflammation, neurodegenerative disorders, and aging. Among the various heat shock proteins, heme oxygenase-1 has received considerable attention; it has been recently demonstrated that heme oxygenase-1 induction, by generating the vasoactive molecule carbon monoxide and the potent antioxidant bilirubin, could represent a protective system potentially active against brain oxidative injury. Acetyl-L-carnitine is proposed as a therapeutic agent for several neurodegenerative disorders. Accordingly, we report here that treatment of astrocytes with acetyl-L-carnitine induces heme oxygenase-1 in a dose- and time-dependent manner and that this effect was associated with up-regulation of heat shock protein 60 as well as high expression of the redox-sensitive transcription factor Nrf2 in the nuclear fraction of treated cells. In addition, we show that addition of acetyl-L-carnitine to astrocytes, prior to proinflammatory lipopolysaccharide- and interferon-gamma-induced nitrosative stress, prevents changes in mitochondrial respiratory chain complex activity, protein nitrosation and antioxidant status induced by inflammatory cytokine insult. Given the broad cytoprotective properties of the heat shock response, molecules inducing this defense mechanism appear to be possible candidates for novel cytoprotective strategies. Particularly, manipulation of endogenous cellular defense mechanisms via acetyl-L-carnitine may represent an innovative approach to therapeutic intervention in diseases causing tissue damage, such as neurodegeneration. We hypothesize that maintenance or recovery of the activity of vitagenes may delay the aging process and decrease the risk of age-related diseases.
维持和修复过程的有效运作对于生存和生活质量似乎至关重要。这是通过一个复杂的所谓长寿保障过程网络来实现的,该网络受几种称为维它基因的基因控制。这些基因包括热休克蛋白系统的成员,现在有证据表明热休克反应有助于在包括炎症、神经退行性疾病和衰老在内的多种人类状况下建立细胞保护状态。在各种热休克蛋白中,血红素加氧酶-1受到了相当多的关注;最近已证明,血红素加氧酶-1的诱导通过产生血管活性分子一氧化碳和强效抗氧化剂胆红素,可能代表一种对脑氧化损伤具有潜在活性的保护系统。乙酰-L-肉碱被提议作为几种神经退行性疾病的治疗剂。因此,我们在此报告,用乙酰-L-肉碱处理星形胶质细胞会以剂量和时间依赖性方式诱导血红素加氧酶-1,并且这种效应与热休克蛋白60的上调以及处理后细胞细胞核部分中氧化还原敏感转录因子Nrf2的高表达有关。此外,我们表明,在促炎性脂多糖和干扰素-γ诱导的亚硝化应激之前向星形胶质细胞中添加乙酰-L-肉碱,可防止炎症细胞因子损伤诱导的线粒体呼吸链复合体活性、蛋白质亚硝化和抗氧化状态的变化。鉴于热休克反应具有广泛的细胞保护特性,诱导这种防御机制的分子似乎可能是新型细胞保护策略的候选者。特别是,通过乙酰-L-肉碱操纵内源性细胞防御机制可能代表一种针对导致组织损伤的疾病(如神经退行性变)进行治疗干预的创新方法。我们假设维它基因活性的维持或恢复可能会延缓衰老过程并降低与年龄相关疾病的风险。