The Effects of Tumor Necrosis Factor - alpha on the Superoxide Radical and Superoxide Dismutase in Cultured Human Keratinocytes.
- Author:
Chang Kwun HONG
;
Seong Jun SEO
;
Byung In RO
- Publication Type:Original Article
- Keywords:
Tumor Necrosis Bactor-a;
Keratinocyte
- MeSH:
Foreskin;
Humans*;
Inflammation;
Keratinocytes*;
Superoxide Dismutase*;
Superoxides*;
Tumor Necrosis Factor-alpha*
- From:Korean Journal of Dermatology
1995;33(1):19-27
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Superoxide dismutases (SOD) are important metallo-enzymes which scavenge and dismutase the superoxide free radical. They are thought to be the main enzymes in the antioxidant defense system. In the several cell ines the induction of Mn-SOD expression by tumor necrosis factor (TNF)-alpha which is a known inflammatory cytokine, suggests that Mn-SOD may play a role in the inflammatory process. However, this effect is occurred. OBJECTIVE: The present study was undertakento determine whether the induction of SOD expression by TNF-alpha, in the keratinocytes is occurred. METHODS: Primary keratinocyte cultures from neonatal foreskins were grown in complete MCDB 153 medium. Measurement of superoxide radical and SOD activity were performed according to Babior and Fridovich methods, respectively. RESULTS: 1. The release of superoxide radical were measured after 30, 60, 90 minutes exposure to 10ng/ms TNF-alpha, THE RESULTS SHOWS 2.94+/-0.30 NMOL/2x105, 3.55+/-0.52 NMOL/2x105, 4.13+/-0.70 nmol/2x105 respectivelyl The increase of superoxide radical release was detectable in a time dependent manner. 2. Total SOD activity without treatment of TNF-alpha at 24 hours was 18.46+/-2.85, Total SOD activities after treatment of 1, 10, 100 ng/ml TNF-alpha at 24hours were 36.47+/-6.80, 88.01+/-7.79, 94.50+/-8.97 respectively, which suggested that TNF-alpha induced increase of total SOD significantly (p<0.050. TNF-alpha stimulate total SOD induction in a dose and time dependent manner, although the effects were not outstanding. Mn-SOD activity after treatment of 100 ng/ml TNF-alpha at 48 hours was 84.12+/-14.83, which was approxdimately 10.5 fold of that of the untredated case. TNF-alpha also induced the Cu, Zn-SOD activity, but the effect was not so much as in the case of Mn -SOD. CONCLUSION: TNF-alpha induces production of total SODD activities, especially Mn-SOD in the human kerati ocytes, which may be to protect cells from inflammation mediated oxidative damage, namely production of total SOD protein, especially Mn-SOD in response to TNF-alpha induced and scavenged overproduced superoxide radical which in turn may result in protection of the keratinocytes.
