Relationships between tissue concentrations of chlorinated hydrocarbons (polychlorinated biphenyls and chlorinated pesticides) and antioxidative responses of marine mussels, Perna viridis

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Abstract

Marine mussels, Perna viridis, were transplanted from a reference site to various polluted sites around Hong Kong. After 30 d of exposure, antioxidative responses in the gills and hepatopancreas and tissue concentrations of chlorinated hydrocarbons [polychlorinated biphenyls (PCBs) and chlorinated pesticides (CPs)] were determined for individual mussels. Glutathione S transferase (GST) and glutathione (GSH) were positively correlated with tissue PCB concentrations. Only one of the enzymatic antioxidants, glutathione peroxidase (GPx), showed significant response to tissue PCB. No significant correlation was found between tissue concentrations of chlorinated hydrocarbons and other enzymatic antioxidants (superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) and NADPH DT-diaphorase (DT-d). Oxidative stress, measured as thiobarbituric acid reactive substances, was correlated with chlorinated pesticide concentrations in tissues. This study demonstrated a correlation between GST/GSH and chlorinated hydrocarbons. The apparent lack of correlation between trace organic pollutants and some of the enzymatic antioxidants may be due to the inhibitory effects caused by these chemicals. The above results suggest that more investigations are needed before these enzymes can be used as biomarkers.

Introduction

Although the sale and use of polychlorinated biphenyls (PCBs) have been banned in many countries for almost 20 years, PCB congeners and related polyhalogenated hydrocarbons still pose a serious threat to aquatic organisms. Besides causing reproductive failures in mammals (Addison, 1989) and birds (Kubiak, 1989), PCBs have been found to induce alternations in the metabolism of hormones and lipids.

Chlorinated hydrocarbons like PCBs and chlorinated pesticides (CPs) are ubiquitously distributed and are major environmental pollutants. Environmental risks associated with chlorinated hydrocarbons in a densely populated coastal city like Hong Kong have previously been reviewed and evaluated by Connell et al., 1998a, Connell et al., 1998b, and the conclusion was that PCBs, total DDTs and total HCHs were likely to pose significant risks to the local marine ecosystem.

Antioxidative responses of mammals exposed to xenobiotics (typically induction of antioxidants and antioxidant enzymes) have been extensively studied during the past 10 years. Numerous reports have demonstrated that these responses can be induced in a dose–response manner by free radicals and free radical generating agents, and thus can be used as biomarkers for these substances. Examples of these antioxidant enzymes include superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione reductase (GR) and glutathione S-transferase (GST). Vitamin E and glutathione (GSH) are examples of “non-enzymatic” antioxidants.

In recent years, investigations have been concentrated on the use of antioxidative responses as biomarkers to reflect the pollution level of trace organics. Most of these studies revealed that the antioxidative responses of indigenous animals such as fishes and mussels from polluted areas generally had greater responses than did control populations. For example, Roberts et al. (1987) reported a greater SOD activity in the liver of spot (Leiostomus xanthurus) from a PAH-contaminated site. Similarly, CAT activity was found to increase in channel catfish (Ictalurus punctatus) exposed to mill effluent (Mather-Mihaich and DiGiulio, 1991) and SOD, GPx and CAT were all elevated in the liver of gray mullet collected from contaminated sites (Rodriguez-Ariza et al., 1993).

Recently, several studies have demonstrated the ability of PCBs to induce the production of reactive oxygen species (Palace et al., 1996; Schlezinger et al., 2000; Beyer et al., 1997). It was reported that PCBs with fewer halogens might lead to increased cytochrome P450 activity, which accounted for the majority of PCB metabolism (Mills et al., 1985). However, the inducibility of antioxidant enzymes by PCBs has not been unequivocally demonstrated. In addition, variable responses in the activity of antioxidant enzymes have been observed in silver carp (Hypothalmichthys molitrix) exposed to the herbicide paraquat depending on the level of exposure (Matkovics et al., 1984).

A field-based study was undertaken in Hong Kong waters to investigate the relationship between antioxidative responses and tissue concentrations of common trace organic contaminants [including polycyclic aromatic hydrocarbons (PAHs), PCBs and CPs] using a local mussel, Perna viridis, as the experimental animal. In the field experiment, mussels were transplanted from a relatively clean site to various polluted sites in Hong Kong. After a 30-day field exposure, different antioxidant parameters including GST, SOD, CAT, GPx, GR, NADPH DT-diaphorase (DT-d), GSH and lipid peroxidation were quantified, and tissue concentrations of PAHs, PCBs, and CPs were determined for individual mussels. The relationships between tissue PAH concentrations and antioxidative responses of P. viridis have been reported earlier by Cheung et al. (2001). This paper reports the relationships between tissue concentrations of organochlorines (PCBs and CPs) and antioxidative responses of P. viridis, and attempts to examine the usefulness and adequacy of antioxidative responses in mussels as a general exposure biomarker for trace organics in the subtropical waters of Hong Kong.

Section snippets

Chemicals and reagents

GR, GSH, GSSG and NADPH were purchased from Roche Molecular Biochemicals. Ascorbic acid, bovine serum albumin (BSA), 1-chloro-2,4-dinitrobenzene (CDNB), cumene hydroperoxide, 5,5-dithiobis (2-nitrobenzoic acid) (DTNB), 2,6-dichlorophenol-indophenol (DCPIP), iron sulfate, potassium thiocyanate, pyrogallol, thiobarbituric acid, trichloroacetic acid (TCA) were obtained from Sigma (St. Louis, MO, USA). Dicumarol, dipotassium hydrogen phosphate, hydrogen peroxide, potassium dihydrogen phosphate,

Results

Tissue burdens of total PCBs and CPs are given in Table 1. Levels of PCBs and CPs appeared to be higher at Tsim Sha Tsui as compared to the other sites, although the Kruskal–Wallis test revealed no inter-site differences (Table 1).

Antioxidant parameters of the two target organs (gill and hepatopancreas) and tissue concentrations of PCBs and CPs for individual mussels are summarized in Table 2.

GST activity was greater in the gills than in the hepatopancreas, while the levels of the oxyradical

Discussion

Many environmental pollutants can cause oxidative damage to biological systems. For example, chlorinated biphenyls and pesticides may produce superoxide anion radicals by redox cycling, while transition metals such as iron catalyze the reaction of superoxide anion radicals with hydrogen peroxide to produce hydroxyl radicals by Fenton reactions (Aust et al., 1985; Sies, 1988; Winston and DiGiulio, 1991). Thus, mussels inhabiting environments contaminated with these xenobiotics may be exposed to

Acknowledgements

The work described in this paper was partially supported by grants from the Hong Kong Research Grants Council (Project No.: 8730011 and 9040550), and a grant from CityU (Project No.: 7001030). This project was undertaken during tenure of City University Postgraduate Studentships to C.C.C. Cheung. The authors are grateful for most useful comments by Prof. J.P. Giesy.

References (51)

  • D.R Livingstone et al.

    Apparent induction of cytochrome P450 with immunochemical similarities to CYP1A in digestive gland of the common mussel (Mytilus galloprovincialis L.) with exposure to 2,23,4,45-hexachlorobiphenyl and Arochlor 1254

    Aquatic Toxicology

    (1997)
  • D.R Livingstone et al.

    Development of hepatic CYP1A and blood vitellogenin in eel (Anguilla anguilla) for use as biomarkers in the Thames Estuary, UK

    Marine Environmental Research

    (2000)
  • X.R Michel et al.

    Effects of benzo(a)pyrene, 3,3,4,4-tetrachlorobiphenyl and 2,2,4,4,5,5-hexachlorobiphenyl on the xenobiotic-metabolizing enzymes in the (Mytilus galloprovincialis)

    Aquatic Toxicology

    (1993)
  • D.M Miller et al.

    Studies of ascorbate-dependent, iron-catalyzed lipid peroxidation

    Archives of Biochemistry and Biophysics

    (1989)
  • R.A Mills et al.

    Studies on the structure activity relationships for the metabolism of polybrominated biphenyls by rat liver microsomes

    Toxicology and Applied Pharmacology

    (1985)
  • L.D Peters et al.

    Variation in levels of cytochrome P450 1A, 2B, 2E, and 4A-immunopositive protein in digestive gland of indigenous and transplanted mussel, Mytilus galloprovincialis in Venice Lagoon, Italy

    Marine Environmental Research

    (1998)
  • C Porte et al.

    The integrated use of chemical analysis, cytochrome P450 and stress proteins in mussels to assess pollution along the Galician coast (NW Spain)

    Environmental Pollution

    (2001)
  • B.J Richardson et al.

    Chlorinated hydrocarbon contaminants in Hong Kong surficial sediments

    Chemosphere

    (1999)
  • M.L Roberts et al.

    Temporal changes in AHH and SOD activities in feral spot from the Elizabeth River, a polluted sub-estuary

    Marine Environmental Research

    (1987)
  • J.J Schlezinger et al.

    3,3,4,4-tertachlorobiphenyl oxidation in fish, bird and reptile species: relationship to cytochrome P450 1A inactivation and reactive oxygen production

    Comparative Biochemistry and Physiology Part C

    (2000)
  • M Sole et al.

    Effects of the Aegean Sea oil spill on biotransformation enzymes, oxidative stress and DNA adducts in digestive gland of the mussel (Mytilus edulis) L

    Comparative Biochemistry and Physiology

    (1996)
  • M Sole

    Assessment of the results of chemical analyses combined with biological effects of organic pollution on mussels

    Trends in Analytical Chemistry

    (2000)
  • G.W Winston et al.

    Prooxidant and antioxidant mechanisms in aquatic organisms

    Aquatic Toxicology

    (1991)
  • G.J Zheng et al.

    Concentrations of persistent organic pollutants in surface sediments of the mudflat and mangroves at Mai Po Marshes Nature Reserve, Hong Kong

    Marine Pollution Bulletin

    (2000)
  • R.F Addison

    Organochlorines and marine mammal reproduction

    Canadian Journal of Fisheries and Aquatic Science

    (1989)
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