Environ Health Toxicol.  2015 ;30(1):e2015006. 10.5620/eht.e2015006.

Alteration of hepatic anti-oxidant systems by 4-nonylphenol, a metabolite of alkylphenol polyethoxylate detergents, in Far Eastern catfish Silurus asotus

• Park KH

• KMID: 2380082
• DOI: http://doi.org/10.5620/eht.e2015006

Abstract

OBJECTIVES
This study aimed to estimate the effects of 4-nonylphenol (NP), a ubiquitously present surfactant in aquatic environments, on the anti-oxidant systems of the liver in the Far Eastern catfish Silurus asotus.
METHODS
Changes in biochemical parameters involved in glutathione (GSH)-related and other anti-oxidant systems were analyzed following 4 weeks of 4-NP administration (0.1 and 1.0 mg/kg diet) via a formulated diet to catfish.
RESULTS
4-NP exposure induced an elevation in hepatic lipid peroxide levels and an accompanying decrease in reduced state GSH after 2 weeks, suggesting pro-oxidant effects of the chemical in catfish. This oxidative stress was associated with an inhibition of the GSH-utilizing enzyme glutathione peroxidase at the same time point. This inhibition was restored after 4 weeks. The activities of other anti-oxidant enzymes, i.e., glutathione reductase, superoxide dismutase and catalase were increased after 4 weeks. These enzyme increases occurred more strongly at the higher 4-NP concentration (1.0 mg/kg diet).
CONCLUSIONS
4-NP given to catfish at 0.1 to 1.0 mg/kg diet, concentrations relevant to environmental levels, depletes the endogenous anti-oxidant molecule GSH and temporarily inhibits GSH-related anti-oxidant enzymes. Such declines in anti-oxidant capacity and elevated oxidative stress seem to be compensated eventually by subsequent activation of various anti-oxidant enzyme systems.

Keyword

Anti-oxidant enzymes; Far Eastern catfish Silurus asotus; Glutathione; 4-Nonylphenol

MeSH Terms

Catalase
Catfishes*
Detergents*
Diet
Glutathione
Glutathione Peroxidase
Glutathione Reductase
Liver
Oxidative Stress
Superoxide Dismutase
Catalase
Detergents
Glutathione
Glutathione Peroxidase
Glutathione Reductase
Superoxide Dismutase