TY - JOUR
T1 - Diclofenac toxicity in human intestine ex vivo is not related to the formation of intestinal metabolites
AU - Niu, Xiaoyu
AU - de Graaf, Inge A. M.
AU - Langelaar-Makkinje, Miriam
AU - Horvatovich, Peter
AU - Groothuis, Geny M. M.
PY - 2015/1
Y1 - 2015/1
N2 - The use of diclofenac (DCF), a nonsteroidal anti-inflammatory drug, is associated with a high prevalence of gastrointestinal side effects. In vivo studies in rodents suggested that reactive metabolites of DCF produced by the liver or the intestine might be responsible for this toxicity. In the present study, precision-cut intestinal slices (PCIS) prepared from the jejunum of 18 human donors were used as an ex vivo model to investigate whether DCF intestinal metabolites are responsible for its intestinal toxicity in man. PCIS were incubated with a concentration range of DCF (0-600 A mu M) up to 24 h. DCF (a parts per thousand yen400 A mu M) caused direct toxicity to the intestine as demonstrated by ATP depletion, morphological damage, caspase 3 activation, and lactate dehydrogenase leakage. Three main metabolites produced by PCIS (4'-hydroxy DCF, 5-hydroxy DCF, and DCF acyl glucuronide) were detected by HPLC. Protein adducts were detected by immunohistochemical staining and showed correlation with the intestinal metabolites. DCF induced similar toxicity to each of the samples regardless of the variation in metabolism among them. Less metabolites were produced by slices incubated with 400 A mu M DCF than with 100 A mu M DCF. The addition of the metabolic inhibitors such as ketoconazole, cimetidine, or borneol decreased the metabolite formation but increased the toxicity. The results suggest that DCF can induce intestinal toxicity in human PCIS directly at therapeutically relevant concentrations, independent of the reactive metabolites 4'-OH DCF, 5-OH DCF, or diclofenac acylglucuronide produced by the liver or formed in the intestine.
AB - The use of diclofenac (DCF), a nonsteroidal anti-inflammatory drug, is associated with a high prevalence of gastrointestinal side effects. In vivo studies in rodents suggested that reactive metabolites of DCF produced by the liver or the intestine might be responsible for this toxicity. In the present study, precision-cut intestinal slices (PCIS) prepared from the jejunum of 18 human donors were used as an ex vivo model to investigate whether DCF intestinal metabolites are responsible for its intestinal toxicity in man. PCIS were incubated with a concentration range of DCF (0-600 A mu M) up to 24 h. DCF (a parts per thousand yen400 A mu M) caused direct toxicity to the intestine as demonstrated by ATP depletion, morphological damage, caspase 3 activation, and lactate dehydrogenase leakage. Three main metabolites produced by PCIS (4'-hydroxy DCF, 5-hydroxy DCF, and DCF acyl glucuronide) were detected by HPLC. Protein adducts were detected by immunohistochemical staining and showed correlation with the intestinal metabolites. DCF induced similar toxicity to each of the samples regardless of the variation in metabolism among them. Less metabolites were produced by slices incubated with 400 A mu M DCF than with 100 A mu M DCF. The addition of the metabolic inhibitors such as ketoconazole, cimetidine, or borneol decreased the metabolite formation but increased the toxicity. The results suggest that DCF can induce intestinal toxicity in human PCIS directly at therapeutically relevant concentrations, independent of the reactive metabolites 4'-OH DCF, 5-OH DCF, or diclofenac acylglucuronide produced by the liver or formed in the intestine.
KW - Diclofenac
KW - Precision-cut intestinal slices
KW - Toxicity
KW - Metabolism
KW - NONSTEROIDAL ANTIINFLAMMATORY DRUGS
KW - LIVER PROTEIN ADDUCTS
KW - PRECISION-CUT SLICES
KW - IN-VITRO
KW - ACYL GLUCURONIDE
KW - SMALL-BOWEL
KW - CYTOCHROME-P450 ENZYMES
KW - CAPSULE ENTEROSCOPY
KW - INDUCED ENTEROPATHY
KW - HUMAN HEPATOCYTES
U2 - 10.1007/s00204-014-1242-6
DO - 10.1007/s00204-014-1242-6
M3 - Article
C2 - 24770551
SN - 0340-5761
VL - 89
SP - 107
EP - 119
JO - Archives of toxicology
JF - Archives of toxicology
IS - 1
ER -