Inhibition of creatine kinase activity in vitro by ethylmalonic acid in cerebral cortex of young rats

• Published in: Neurochemical research 2002-12, Vol.27 (12), p.1633-1639
• Main Authors: SCHUCK, Patricia F, LEIPNITZ, Guilhian, RIBEIRO, César A. J, DALCIN, Karina B, ASSIS, Dênis R, BARSCHAK, Alethea G, PULROLNIK, Vania, WANNMACHER, Clovis M. D, WYSE, Angela T. S, WAJNER, Moacir
• Format: Article
• Language: English
• Subjects: alpha-Tocopherol - pharmacology; Animals; Ascorbic Acid - pharmacology; Biological and medical sciences; Cerebral Cortex - drug effects; Cerebral Cortex - enzymology; Creatine Kinase - antagonists & inhibitors; Enzyme Inhibitors - pharmacology; Fundamental and applied biological sciences. Psychology; Glutathione - pharmacology; In Vitro Techniques; Malonates - pharmacology; NG-Nitroarginine Methyl Ester - pharmacology; Nitric Oxide Synthase - antagonists & inhibitors; Rats; Rats, Wistar
• ISSN: 0364-3190; 1573-6903
• DOI: 10.1023/A:1021682910373

Short-chain acyl-CoA dehydrogenase deficiency is an inherited metabolic disorder biochemically characterized by tissue accumulation of ethylmalonic (EMA) and methylsuccinic (MSA) acids and clinically by severe neurological symptoms. In the present study we investigated the in vitro effects of EMA and MSA on the activity of creatine kinase (CK) in homogenates from cerebral cortex, skeletal and cardiac muscle of rats. EMA significantly inhibited CK activity from cerebral cortex, but did not affect this activity in skeletal and cardiac muscle. Furthermore, MSA had no effect on this enzyme in all tested tissues. Glutathione (GSH), ascorbic acid and alpha-tocopherol, and the nitric oxide synthase inhibitor L-NAME, did not affect the enzyme activity per se, but GSH fully prevented the inhibitory effect of EMA when co-incubated with EMA. In contrast, alpha-tocopherol, ascorbic acid and L-NAME did not influence the inhibitory effect of the acid. The data suggest that inhibition of brain CK activity by EMA is possibly mediated by oxidation of essential groups of the enzyme, which are protected by the potent intracellular, endogenous, naturally occurring antioxidant GSH.