title: Comparing myotoxic effects of squalene synthase inhibitor, T-91485, and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors in human myocytes.
abstract: TAK-475 is a squalene synthase inhibitor, rapidly metabolized to T-91485 in vivo. We investigated the myotoxicities of T-91485 and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors in a human rhabdomyosarcoma cell line, RD, and in human skeletal myocytes. In differentiated RD cells, T-91485, atorvastatin (ATV) and simvastatin acid (SIM) inhibited cholesterol biosynthesis, with IC(50) values of 36, 2.8 and 3.8 nM, respectively. ATV and SIM decreased the intracellular ATP content, with IC(25) values (concentrations giving a 25% decrease in intracellular ATP content) of 0.61 and 0.44 microM, respectively. Although T-91485 potently inhibited cholesterol synthesis in RD cells, the IC(25) value exceeded 100 microM. In human skeletal myocytes, T-91485, ATV and SIM concentration-dependently inhibited cholesterol biosynthesis, with IC(50) values of 45, 8.6 and 8.4 nM, respectively. ATV and SIM decreased intracellular ATP content, with IC(25) values of 2.1 and 0.72 microM, respectively. Although T-91485 potently inhibited cholesterol synthesis, the IC(25) value exceeded 100 microM. Myotoxicity induced by ATV was prevented by mevalonate or geranylgeranyl-PP, but not by squalene in skeletal cells. Furthermore, T-91485 attenuated the myotoxicity of ATV. These findings suggest that TAK-475 and T-91485 may not only be far from myotoxic, they may also decrease statin-induced myotoxicity in lipid-lowering therapy.
authors: Pharmacology Research Laboratories I, Pharmaceutical Research Division, Takeda Chemical Industries, Ltd., Yodogawa-ku, Osaka 532-8686, Japan. Nishimoto_Tomoyui@takeda.co.jp
authors: Tomoyuki
authors: T
authors: Nishimoto
authors: Ryuichi
authors: R
authors: Tozawa
authors: Yuichiro
authors: Y
authors: Amano
authors: Takeo
authors: T
authors: Wada
authors: Yoshimi
authors: Y
authors: Imura
authors: Yasuo
authors: Y
authors: Sugiyama
mesh_terms: D045744:Cell Line, Tumor; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D013186:Farnesyl-Diphosphate Farnesyltransferase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D006801:Humans; D006903:Hydroxymethylglutaryl CoA Reductases / Q000378:metabolism; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D018485:Muscle Fibers, Skeletal / Q000187:drug effects* / Q000201:enzymology*; D010077:Oxazepines / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D010880:Piperidines / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*
chemical_list: C466644:1-((1-(3-acetoxy-2,2-dimethylpropyl)-7-chloro-5-(2,3-dimethoxyphenyl)-2-oxo-1,2,3,5-tetrahydro-4,1-benzoxazepin-3-yl)acetyl)piperidine-4-acetic acid; D004791:Enzyme Inhibitors; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D010077:Oxazepines; D010880:Piperidines; D006903:Hydroxymethylglutaryl CoA Reductases; D013186:Farnesyl-Diphosphate Farnesyltransferase