Sensitivity of (1)H NMR analysis of rat urine in relation to toxicometabonomics. Part I: dose-dependent toxic effects of bromobenzene and paracetamol.
(1)H nuclear magnetic resonance (NMR) spectroscopy of rat urine in combination with pattern recognition analysis was evaluated for early noninvasive detection of toxicity of investigational chemical entities. Bromobenzene (B) and paracetamol (P) were administered at five single oral dosages between 2 and 500 mg/kg and between 6 and 1800 mg/kg, respectively. The sensitivity of the proposed method to detect changes in the NMR spectra 24 and 48 h after single dosing was compared with histopathology and biochemical parameters in plasma and urine. Both B and P applied at the highest dosages induced liver necrosis and markedly increased aspartate aminotransferase (AST) and alanine aminotransferase (ALT) plasma levels. At dosages of 125 mg/kg B and 450 mg/kg P, liver necrosis and changes in AST and ALT were less pronounced, while at lower dose levels these effects could not be detected. Changes in kidney pathology or standard urine biochemistry were not observed at any of these dosages. Evaluation of the total NMR dataset showed 80 signals to be sensitive for B and P dosing. Principal component analysis on the reduced dataset revealed that NMR spectra were significantly different at dosages above 8 mg/kg (B) and 110 mg/kg (P) at both sampling times. This implies a 4- to 16-fold increased sensitivity of NMR versus histopathology and clinical chemistry in recognizing early events of liver toxicity.
Schoonen
Willem G E J
WG
Department of Pharmacology, N.V. Organon, Molenstraat 110, 5340 BH Oss, The Netherlands. willem.schoonen@organon.com
Kloks
Cathelijne P A M
CP
Ploemen
Jan-Peter H T M
JP
Horbach
G Jean
GJ
Smit
Martin J
MJ
Zandberg
Pieter
P
Mellema
Jan-Remt
JR
Zuylen
Carol Thijssen-van
CT
Tas
Albert C
AC
van Nesselrooij
Joop H J
JH
Vogels
Jack T W E
JT
D000082:Acetaminophen / Q000633:toxicity* / Q000652:urine*; D000410:Alanine Transaminase / Q000097:blood; D018712:Analgesics, Non-Narcotic / Q000633:toxicity* / Q000652:urine*; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D001969:Bromobenzenes / Q000633:toxicity* / Q000652:urine*; D056486:Chemical and Drug Induced Liver Injury / Q000201:enzymology / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D007668:Kidney / Q000473:pathology; D008099:Liver / Q000473:pathology; D009682:Magnetic Resonance Spectroscopy; D009336:Necrosis / Q000473:pathology; D025341:Principal Component Analysis; D051381:Rats
D018712:Analgesics, Non-Narcotic; D001969:Bromobenzenes; D000082:Acetaminophen; C032036:bromobenzene; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase