Abstract
Samples of Sarotherodon melanotheron obtained from water bodies of
different pollution histories, that is, a site on the Volta lake near
Ada, the Fosu lagoon at Cape Coast and aquaria containing the
herbicide, 'Roundup', were used to investigate induction of hepatic
cytochrome P-450 monooxygenase enzyme system (CYP) and glutathione-stransferase (GST) in response to pollutants.
Total microsomal protein concentration was determined by the FolinLowry method. The activity of NADPH cytochrome P-450 reductase, a
component of monooxygenase enzyme system, was measured, using
reduction of exogenous cytochrome C. Another component, cytochrome
P-450, was measured using CO-difference spectrum. The overall
monooxygenase activity was determined using 7-ethoxyresorufin-0-
deethylase (EROD) and 7-pentoxyresorufin-O-depentylase (PROD) assays,
which indicated specifically, the induction of cytochrome P-4501A and
P-4502B isoenzymes respectively. Glutathione-s-transferase activity
was measured using l-chloro-2,4-dinitrobenzene as the substrate.
The results for all the biochemical parameters measured, indicated
that the levels of those of the fish from Fosu lagoon were
excessively higher than the values recorded for fish from Volta lake
and the aquaria, indicating a relatively higher pollution level in
the Fosu lagoon. For the CYP the levels measured for both fish from
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the Fosu lagoon and the aquaria were almost similar, indicating
higher induction of CYP by 'Roundup' . For the EROD and PROD
determinations for the monooxygenase system, activities were detected
in livers of fish from Fosu lagoon and the Volta lake. No such
activities were detected in fish exposed to 'Roundup', even though
CYP induction was high and these monooxygenase enzyme activities were
found prior to herbicide exposure. The activity of EROD was 3.5 fold
higher than that of PROD, indicating less PB-types of inducers than
that of 3-MC type in the Fosu lagoon.
This study has indicated that the Fosu lagoon is polluted with 3-MC
types and PB-types of inducers and that the 'Roundup'-induced CYP is
not only different from the CYP isozymes responsible for the EROD and
PROD assays, it actually inactivates them. GST induction indicated
in this study would support the effects of the induced CYP in
biotransformation of the xenobiotics which enter the fish in polluted
waters.
Eastern Network, L (2021). Cytochrome P-450 Monooxygenase Complex And Glutathione-Stransferase In Sarotherodon Melano Theron As Biomarkers Of Pollution.. Afribary.com: Retrieved April 10, 2021, from https://afribary.com/works/cytochrome-p-450-monooxygenase-complex-and-glutathione-stransferase-in-sarotherodon-melano-theron-as-biomarkers-of-pollution
Library, Eastern Network. "Cytochrome P-450 Monooxygenase Complex And Glutathione-Stransferase In Sarotherodon Melano Theron As Biomarkers Of Pollution." Afribary.com. Afribary.com, 07 Apr. 2021, https://afribary.com/works/cytochrome-p-450-monooxygenase-complex-and-glutathione-stransferase-in-sarotherodon-melano-theron-as-biomarkers-of-pollution . Accessed 10 Apr. 2021.
Library, Eastern Network. "Cytochrome P-450 Monooxygenase Complex And Glutathione-Stransferase In Sarotherodon Melano Theron As Biomarkers Of Pollution.". Afribary.com, Afribary.com, 07 Apr. 2021. Web. 10 Apr. 2021. < https://afribary.com/works/cytochrome-p-450-monooxygenase-complex-and-glutathione-stransferase-in-sarotherodon-melano-theron-as-biomarkers-of-pollution >.
Library, Eastern Network. "Cytochrome P-450 Monooxygenase Complex And Glutathione-Stransferase In Sarotherodon Melano Theron As Biomarkers Of Pollution." Afribary.com (2021). Accessed April 10, 2021. https://afribary.com/works/cytochrome-p-450-monooxygenase-complex-and-glutathione-stransferase-in-sarotherodon-melano-theron-as-biomarkers-of-pollution