Effects of bisphenol A and fadrozole exposures on cyp19a1 expression in the Murray rainbowfish, Melanotaenia fluviatilis
journal contribution
posted on 2023-05-18, 03:42authored bySanthanagouda, AH, Nugegoda, D, Jawahar PATIL
Several endocrine-disrupting chemicals (EDCs) have been attributed to the alteration of reproduction in fish through disrupting endogenous sex steroidogenic pathways including aromatisation of androgens to oestrogen by CYP19 aromatase. Here we investigate this hypothesis in adult male and female Melanotaenia fluviatilis by examining the mRNA expression of cyp19a1 isoforms after exposure for ≤96 h to two EDCs with contrasting modes of action: one a weak oestrogen mimic, bisphenol A [BPA (100 or 500 μg/L)], and the other a nonsteroidal aromatase inhibitor, fadrozole [FAD (10 or 50 µg/L)]. The results suggest that BPA did not affect cyp19a1a expression significantly at both concentrations, whereas 50 µg/L of FAD significantly upregulated its expression in ovary. In contrast, BPA exposures increased expression of cyp19a1b in brain of both males and females, whilst FAD had contrasting effects in brain: It increased in males but decreased in females. Similar contrasting responses of cyp19a1b were induced by BPA in gonads: upregulation in ovary and downregulation in testis. FAD did not have a significant effect on gonadal expression of cyp19a1b. Collectively, the results suggest that BPA and FAD can disrupt cyp19a1b activity more readily than can cyp19a1a, albeit with contrasting effects in either a tissue- or sex-specific context that is conceivably consistent with their (BPA and FAD) opposing modes of action. Enhanced spatial and temporal sensitivity of cyp19a1b compared with cyp19a1a suggests that brain sex of fish is more susceptible to disruption by environmental pollutants such as BPA and FAD. Therefore, we propose that the response of cyp19a1b in brain tissue of M. fluviatilis is a more suitable indicator of oestrogenic pollution in the aquatic environment
History
Publication title
Archives of Environmental Contamination and Toxicology
Volume
67
Pagination
270-280
ISSN
0090-4341
Department/School
Institute for Marine and Antarctic Studies
Publisher
Springer-Verlag
Place of publication
175 Fifth Ave, New York, USA, Ny, 10010
Rights statement
Copyright 2014 Springer Science+Business Media New York
Repository Status
Restricted
Socio-economic Objectives
Assessment and management of benthic marine ecosystems