title: Mitochondrial superoxide dismutase and glutathione peroxidase in idiosyncratic drug-induced liver injury.
abstract: Drug-induced liver injury (DILI) susceptibility has a potential genetic basis. We have evaluated possible associations between the risk of developing DILI and common genetic variants of the manganese superoxide dismutase (SOD2 Val16Ala) and glutathione peroxidase (GPX1 Pro200Leu) genes, which are involved in mitochondrial oxidative stress management. Genomic DNA from 185 DILI patients assessed by the Council for International Organizations of Medical Science scale and 270 sex- and age-matched controls were analyzed. The SOD2 and GPX1 genotyping was performed using polymerase chain reaction restriction fragment length polymorphism and TaqMan probed quantitative polymerase chain reaction, respectively. The statistical power to detect the effect of variant alleles with the observed odds ratio (OR) was 98.2% and 99.7% for bilateral association of SOD2 and GPX1, respectively. The SOD2 Ala/Ala genotype was associated with cholestatic/mixed damage (OR = 2.3; 95% confidence interval [CI] = 1.4-3.8; corrected P [Pc] = 0.0058), whereas the GPX1 Leu/Leu genotype was associated with cholestatic injury (OR = 5.1; 95%CI = 1.6-16.0; Pc = 0.0112). The presence of two or more combined risk alleles (SOD2 Ala and GPX1 Leu) was more frequent in DILI patients (OR = 2.1; 95%CI = 1.4-3.0; Pc = 0.0006). Patients with cholestatic/mixed injury induced by mitochondria hazardous drugs were more prone to have the SOD2 Ala/Ala genotype (OR = 3.6; 95%CI = 1.4-9.3; Pc = 0.02). This genotype was also more frequent in cholestatic/mixed DILI induced by pharmaceuticals producing quinone-like or epoxide metabolites (OR = 3.0; 95%CI = 1.7-5.5; Pc = 0.0008) and S-oxides, diazines, nitroanion radicals, or iminium ions (OR = 16.0; 95%CI = 1.8-146.1; Pc = 0.009).
  
  
  CONCLUSIONS
  Patients homozygous for the SOD2 Ala allele and the GPX1 Leu allele are at higher risk of developing cholestatic DILI. SOD2 Ala homozygotes may be more prone to suffer DILI from drugs that are mitochondria hazardous or produce reactive intermediates.
authors.affiliation: Servicio de Farmacología Clínica y Grupo de Estudio para las Hepatopatias Asociadas a Medicamentos, Coordinating Centre, Facultad de Medicina, Hospital Universitario Virgen de la Victoria, Campus Universitario s/n, Málaga, Spain.
authors.forename: M Isabel
authors.initials: MI
authors.lastname: Lucena
authors.forename: Elena
authors.initials: E
authors.lastname: García-Martín
authors.forename: Raúl J
authors.initials: RJ
authors.lastname: Andrade
authors.forename: Carmen
authors.initials: C
authors.lastname: Martínez
authors.forename: Camilla
authors.initials: C
authors.lastname: Stephens
authors.forename: Jhon D
authors.initials: JD
authors.lastname: Ruiz
authors.forename: Eugenia
authors.initials: E
authors.lastname: Ulzurrun
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Fernandez
authors.forename: Manuel
authors.initials: M
authors.lastname: Romero-Gomez
authors.forename: Augustin
authors.initials: A
authors.lastname: Castiella
authors.forename: Ramon
authors.initials: R
authors.lastname: Planas
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Durán
authors.forename: Ana Melcón
authors.initials: AM
authors.lastname: De Dios
authors.forename: Carlos
authors.initials: C
authors.lastname: Guarner
authors.forename: German
authors.initials: G
authors.lastname: Soriano
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Borraz
authors.forename: José A G
authors.initials: JA
authors.lastname: Agundez
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D019943:Amino Acid Substitution; D056486:Chemical and Drug Induced Liver Injury / Q000235:genetics*; D005260:Female; D005979:Glutathione Peroxidase / Q000235:genetics*; D006801:Humans; D007930:Leucine / Q000235:genetics; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000201:enzymology*; D011110:Polymorphism, Genetic; D013482:Superoxide Dismutase / Q000235:genetics*; D055815:Young Adult; D000094765:Glutathione Peroxidase GPX1; D000099156:Superoxide Dismutase 2
chemical_list: D005979:Glutathione Peroxidase; D007930:Leucine; D013482:Superoxide Dismutase; D000094765:Glutathione Peroxidase GPX1; D000099156:Superoxide Dismutase 2; C000722067:GPX1 protein, human