CYP1A expression in liver and gills of roach (Rutilus rutilus) after waterborne exposure to two phenanthrene derivatives, 1-methylphenanthrene and 4-methylphenanthrene

Abstract

Phenanthrenes (Phs) substituted with alkyl groups are a class of compound present in the environment, and they appear to be toxic to developing fish. The present study aimed to investigate the effect of waterborne exposure to two monomethyl derivatives of phenanthrene, 1-methylphenanthrene (1M-Ph) and 4-methylphenanthrene (4M-Ph), on cytochrome P450 1A (CYP1A) gene expression in fish gills and liver. Juvenile common roaches (Rutilus rutilus) were exposed to water with dimethyl sulfoxide (DMSO) solutions of 1M-Ph, 4M-Ph, benzo[a]pyrene (BaP; positive control), each at a dose of 100 µg/L, or to water with DMSO alone (negative control group) for 2 d and 7 d. Significant CYP1A responses with regard to treatment and exposure duration were noted (2-way analysis of variance [ANOVA]) in gills (p = 0.013 and p = 0.003, respectively) and liver (p < 0.001). The 2 monomethyl Phs did not induce consistent gene expression changes, except for 4-MPh, which elevated the CYP1A messenger ribonucleic acid (mRNA) level in the liver at the end of the treatment (almost 4-fold; p < 0.05; 7 d). As was expected, exposure to BaP resulted in elevation of CYP1A mRNA expression in treated fish compared with the control group. Expressions after 2 d and 7 d were approximately 220- and 180-fold higher in liver and 8- and 6-fold higher in gills respectively. The CYP1A protein levels remained stable in both tissues, with one notable exception in roach liver treated for 2 d with BaP (∼ 6-fold increase; p < 0.05). The different effects of the 1- and 4-methylphenanthrenes on CYP1A gene expression in roach liver suggest a relationship between chemical or 3-D structure of the differentially substituted monomethyl Phs and their biological activity.

Mechanisms of phenanthrene toxicity in the soil invertebrate, Enchytraeus crypticus

“…All rights reserved exposure. This is in clear contrast with previous observations in F. candida that showed a distinct role of genes coding for biotransformation enzymes in response to phenanthrene toxicity [3,18], although cytochrome P450 1A1 has been implicated in phenanthrene detoxification in fish [19,20], mice, and humans [21].…”

“…Environ Toxicol Chem 35, 2016 transporters and were significantly up-regulated at the EC50 level after 2 d and 21 d. Finally, 1 transcript could be attributed to glutathione-S-transferase, which was significantly downregulated after 2 d of EC50 exposure. This is in clear contrast with previous observations in F. candida that showed a distinct role of genes coding for biotransformation enzymes in response to phenanthrene toxicity [3,18], although cytochrome P450 1A1 has been implicated in phenanthrene detoxification in fish [19,20], mice, and humans [21]. The gene ontology enrichment analysis results are presented in Table 1.…”

CYP1A gene expression as a basic factor for fipronil toxicity in Caspian kutum fish

“…The sequences of designed primers were forward: 5′-AATCGTCAATGACCTCTTCGG-3′ (21 bp, GC%: 47.6 and Tm: 59.4 ° C) and reverse: 5′-ATCTCGGGATAGGACACTAGATAG-3′ (24 bp, GC%: 45.8% and Tm: 63.5 ° C) for target gene (89 bp). The reference gene (94 bp) was ribosomal protein L8 of roach [ 25 ] with the following primers: forward: 5′-ATC CCG AGA CCA AGA AAT CCA GAG-3′; reverse: 5′-CCA GCA ACA CCA ACA G-3′.…”

Characterisation of transcriptional responses to dioxins and dioxin-like contaminants in roach ( Rutilus rutilus ) using whole transcriptome analysis

“…In comparison with more frequently investigated model species of fish, the effects of DLCs on roach have received little attention and only their basic biochemical effects (e.g. the induction of biotransformation enzymes) have been reported to date (Machala et al, 2000;Oikari and Kukkonen, 1988;Smith and Hill, 2004;Wolinska et al, 2013). Information regarding adverse effects and their associated mechanisms has not been reported for this species.…”