Evaluation of Azathioprine-Induced Cytotoxicity in an In Vitro Rat Hepatocyte System

Table 1

AZA-induced oxidative stress with GSH depletion and protection with a GSH precursor, a xanthine oxidase inhibitor, various antioxidants, and a radical scavenger.

Addition	ROS (FI unit)	MMP (%)	H2O2 (nmoles/10^6cells)
Incubation time	30 min	30 min	30 min
Control	102 ± 1	100	6.34 ± 0.07
+400 μM AZA	139 ± 3^a	86 ± 1^a	8.11 ± 0.08^a
+GSH-depleted hepatocytes	174 ± 5^a,b	75 ± 1^a,b	9.21 ± 0.13^a,b
+1 mM NAC	124 ± 3^a,b	89 ± 1^a	6.97 ± 0.04^a,b
+20 μM allopurinol	132 ± 3^a	92 ± 1^a,b	7.75 ± 0.19^a
+1 mM NAC + 20 μM allopurinol	107 ± 1^b	97 ± 2^b	6.54 ± 0.14^b
+1 mM mesna	121 ± 3^a,b	93 ± 2^a,b	7.10 ± 0.18^a,b
+1 mM Trolox	113 ± 3^b	94 ± 2^a,b	7.12 ± 0.02^a,b
+200 μM TEMPOL	123 ± 4^a,b	93 ± 1^a,b	7.46 ± 0.18^a,b
+2 μM DPPD	124 ± 2^a,b	92 ± 2^a,b	7.26 ± 0.06^a,b

Data are presented as mean ± SEM (𝑛=3). All modulating agents were noncytotoxic compared to control hepatocytes at concentrations used. Refer to Section 2 for a description of the experiments performed and experimental conditions. FI, fluorescence intensity; NAC, N-acetylcysteine; mesna, 2-mercaptoethanesulfonate; Trolox, 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid; TEMPOL, 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl; DPPD, N,N′-diphenyl-p-phenylenediamine; asignificant compared to control (only hepatocytes); bsignificant compared to 400 μM AZA.