Activation of c-Jun N-terminal kinase is essential for oxidative stress-induced Jurkat cell apoptosis by monochloramine

Pathology and Experimental Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata, Okayama 700-8558, Japan.
Leukemia Research (Impact Factor: 2.69). 09/2008; 33(1):151-8. DOI: 10.1016/j.leukres.2008.07.009
Source: PubMed

ABSTRACT Leukemic cell apoptosis may be enhanced by appropriate oxidative stress. We report here the mechanism of Jurkat cell apoptosis by monochloramine (NH(2)Cl), a neutrophil-derived oxidant. NH(2)Cl induced caspase-dependent apoptosis, which was preceded by cytochrome c and Smac/Diablo release from mitochondria. Within 10min of NH(2)Cl treatment, c-Jun N-terminal kinase (JNK) activation and elevation of cytosolic Ca(2+) were observed. JNK inhibitors (SP600125 or JNK inhibitor VIII) significantly suppressed the apoptosis as well as caspase cleavage and cytochrome c release. In contrast, Ca(2+) chelation by EGTA+acetoxymethyl-EGTA had no effects on apoptosis. Our results indicated that JNK activation contributed most importantly to the NH(2)Cl-induced apoptosis.

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