title: Cisplatin-induced cytotoxicity in BSO-exposed renal proximal tubular epithelial cells: sex, age, and species.
abstract: BACKGROUND
  Cisplatin (CP)-induced kidney damage and effects of DL-buthionine-(S,R)-sulfoximine (BSO) on it are species- and age-different. It remains unclear whether CP-induced cytotoxicity in renal proximal tubular epithelial cells (RTEC), the main target cells of CP, is also species- and age-different; and whether CP-induced cytotoxicity varies with the difference in age and species, if any, is one of the questions. In the present study, the effects of BSO on CP-induced cytotoxicity in primary cultures of RTEC isolated from monkeys and different age and sex rats were studied.
  
  
  METHODS
  The RTEC were isolated from 3-week-old, 2-month-old, or 5-month-old rats, and 6-8 year-old monkeys. After subculturing, RTEC was inoculated into type I collagen-coated 96-well culture plates; after preincubation, 40 microM BSO was added, 16 hours later, varying concentrations of CP were added. At that time, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays were performed to test cell viability.
  
  
  RESULTS
  The concentrations of CP that inhibited 50% cell growth (IC50) of RTEC from rats and monkeys were 1.11 and 3.03 mM at 8 hours, and 0.51 and 1.24 mM at 24 hours, respectively. The BSO made the IC50s of RTEC from rats and monkeys lower, down to 0.07 and 0.48 mM at 8 hours, and 0.02 and 0.11 mM at 24 hours, respectively. The IC50s of RTEC from different sex and age rats were almost same.
  
  
  CONCLUSIONS
  These results suggested that CP-induced cytotoxicity was concentration- and time-dependent, with species-dependent differences, rat RTEC were more susceptible to CP than monkey RTEC, rat RTEC were more dependent on glutathione (GSH) during the stress state were than monkey cells; CP-induced cytotoxicity was without sex- and age-dependent differences in rat RTEC.
authors.affiliation: Department of Toxicology, Dalian Medical University, Dalian, China. luyongke@yahoo.com
authors.forename: Yongke
authors.initials: Y
authors.lastname: Lu
authors.forename: Akira
authors.initials: A
authors.lastname: Kawashima
authors.forename: Ikuo
authors.initials: I
authors.lastname: Horii
authors.forename: Laifu
authors.initials: L
authors.lastname: Zhong
mesh_terms: D000818:Animals; D019328:Buthionine Sulfoximine; D016923:Cell Death / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002945:Cisplatin / Q000633:toxicity*; D004195:Disease Models, Animal; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects; D005260:Female; D000882:Haplorhini; D007687:Kidney Tubules, Proximal / Q000166:cytology* / Q000187:drug effects*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012737:Sex Factors; D013045:Species Specificity
chemical_list: D019328:Buthionine Sulfoximine; D002945:Cisplatin