Rudin Deborah, Schmutz Maurice, Roos Noëmi Johanna, Bouitbir Jamal, Krähenbühl Stephan
Division of Clinical Pharmacology & Toxicology, University Hospital Basel, Spitalstrasse 21, 4031 Basel, Switzerland.
Department of Biomedicine, University of Basel, Hebelstrasse 20, 4031 Basel, Switzerland.
Biomedicines. 2020 Jul 14;8(7):212. doi: 10.3390/biomedicines8070212.
Metamizole is an analgesic, whose pharmacological and toxicological properties are attributed to N-methyl-aminoantipyrine (MAA), its major metabolite. In the presence of heme iron, MAA forms reactive metabolites, which are toxic for granulocyte precursors. Since decreased cellular ATP is characteristic for MAA-associated toxicity, we studied the effect of MAA with and without hemin on energy metabolism of HL60 cells, a granulocyte precursor cell line. The combination MAA/hemin depleted the cellular ATP stronger than hemin alone, whereas MAA alone was not toxic. This decrease in cellular ATP was observed before plasma membrane integrity impairment. MAA/hemin and hemin did not affect the proton leak but increased the maximal oxygen consumption by HL60 cells. This effect was reversed by addition of the radical scavenger -acetylcysteine. The mitochondrial copy number was not affected by MAA/hemin or hemin. Hemin increased mitochondrial superoxide generation, which was not accentuated by MAA. MAA decreased cellular ROS accumulation in the presence of hemin. In cells cultured in galactose (favoring mitochondrial ATP generation), MAA/hemin had less effect on the cellular ATP and plasma membrane integrity than in glucose. MAA/hemin impaired glycolysis more than hemin or MAA alone, and -acetylcysteine blunted this effect of MAA/hemin. MAA/hemin decreased protein expression of pyruvate kinase more than hemin or MAA alone. In conclusion, cellular ATP depletion appears to be an important mechanism of MAA/hemin toxicity on HL60 cells. MAA itself is not toxic on HL60 cells up to 100 µM but boosts the inhibitory effect of hemin on glycolysis through the formation of reactive metabolites.
安乃近是一种镇痛药，其药理和毒理特性归因于其主要代谢产物N-甲基-氨基安替比林（MAA）。在血红素铁存在的情况下，MAA会形成反应性代谢产物，这些产物对粒细胞前体有毒性。由于细胞ATP降低是MAA相关毒性的特征，我们研究了有或没有血红素的MAA对HL60细胞（一种粒细胞前体细胞系）能量代谢的影响。MAA/血红素组合比单独使用血红素更能消耗细胞ATP，而单独的MAA没有毒性。在质膜完整性受损之前就观察到了细胞ATP的这种降低。MAA/血红素和血红素不影响质子泄漏，但增加了HL60细胞的最大耗氧量。添加自由基清除剂N-乙酰半胱氨酸可逆转这种效应。线粒体拷贝数不受MAA/血红素或血红素的影响。血红素增加了线粒体超氧化物的生成，MAA并没有加剧这种情况。在有血红素存在的情况下，MAA减少了细胞ROS的积累。在以半乳糖培养的细胞（有利于线粒体ATP生成）中，MAA/血红素对细胞ATP和质膜完整性的影响比在葡萄糖中培养的细胞要小。MAA/血红素比单独的血红素或MAA更能损害糖酵解，N-乙酰半胱氨酸减弱了MAA/血红素的这种作用。MAA/血红素比单独的血红素或MAA更能降低丙酮酸激酶的蛋白表达。总之，细胞ATP耗竭似乎是MAA/血红素对HL60细胞毒性的重要机制。在高达100µM的浓度下，MAA本身对HL60细胞没有毒性，但通过形成反应性代谢产物增强了血红素对糖酵解的抑制作用。
