Sánchez-Gómez Francisco J, Dorado Carlos García, Ayuso Pedro, Agúndez Jose A G, Pajares María A, Pérez-Sala Dolores
Chemical and Physical Biology Department, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, 9, 28040 Madrid, Spain.
Inflamm Allergy Drug Targets. 2013 Jun;12(3):162-71. doi: 10.2174/1871528111312030002.
Glutathione S transferase P1-1 plays a key role in the metabolism of inflammatory mediators and drugs, thus modulating the inflammatory response. Active GSTP1-1 is a homodimer with cysteine residues close to the active site that can undergo oligomerization in response to stress, a process that affects enzyme activity and interactions with signaling and redox-active proteins. Cyclopentenone prostaglandins (cyPG) are endogenous reactive lipid mediators that participate in the regulation of inflammation and may covalently modify proteins through Michael addition. cyPG with dienone structure, which can bind to vicinal cysteines, induce an irreversible oligomerization of GSTP1-1. Here we have characterized the oligomeric state of GSTP1-1 in Jurkat cells treated with 15-deoxy-Δ12,14-PGJ (15d-PGJ). 15d-PGJ induces both reversible and irreversible GSTP1-1 oligomerization as shown by blue-native 2D electrophoresis. Interestingly, GSTP1-1 dimers were the main species detected by analytical gel filtration chromatography in control cells, whereas only oligomers, compatible with a tetrameric association state, were found in 15d-PGJ-treated cells. cyPG-induced GSTP1-1 oligomerization also occurred in cell-free systems. Therefore, we employed this model to assess the effects of endogenous reactive species and drugs. Inflammatory mediators, such as 15d-PGJ and Δ12-PGJ, and drugs like chlorambucil, phenylarsine oxide or dibromobimane elicited whereas ethacrynic acid hampered GSTP1-1 oligomerization or intra-molecular cross-linking in cell-free systems, yielding GSTP1-1 species specific for each compound. These observations situate GSTP1-1 at the cross-roads of inflammation and drug action behaving as a target for both inflammatory mediators and reactive drugs, which induce or reciprocally modulate GSTP1-1 oligomerization or conformation.
谷胱甘肽S-转移酶P1-1在炎症介质和药物的代谢中起关键作用，从而调节炎症反应。活性GSTP1-1是一种同二聚体，其半胱氨酸残基靠近活性位点，可在应激时发生寡聚化，这一过程会影响酶活性以及与信号和氧化还原活性蛋白的相互作用。环戊烯酮前列腺素（cyPG）是内源性反应性脂质介质，参与炎症调节，并可能通过迈克尔加成反应共价修饰蛋白质。具有二烯酮结构的cyPG可与相邻的半胱氨酸结合，诱导GSTP1-1发生不可逆的寡聚化。在此，我们对用15-脱氧-Δ12,14-前列腺素J2（15d-PGJ）处理的Jurkat细胞中GSTP1-1的寡聚状态进行了表征。如蓝色非变性二维电泳所示，15d-PGJ诱导GSTP1-1发生可逆和不可逆的寡聚化。有趣的是，分析型凝胶过滤色谱在对照细胞中检测到的主要是GSTP1-1二聚体，而在15d-PGJ处理的细胞中仅发现与四聚体缔合状态相符的寡聚体。cyPG诱导的GSTP1-1寡聚化也发生在无细胞系统中。因此，我们利用该模型评估内源性反应性物质和药物的作用。炎症介质，如15d-PGJ和Δ12-PGJ，以及药物如苯丁酸氮芥、氧化苯胂或二溴双马来酰亚胺会引发，而依他尼酸则会阻碍无细胞系统中GSTP1-1的寡聚化或分子内交联，产生每种化合物特有的GSTP1-1物种。这些观察结果表明，GSTP1-1处于炎症和药物作用的交叉点，既是炎症介质的靶点，也是反应性药物的靶点，它们可诱导或相互调节GSTP1-1的寡聚化或构象。
