Absolute quantification and modulation of cytochrome P450 3A isoforms in cattle liver

Zancanella, Vanessa; Giantin, Mery; Dacasto, Mauro

doi:10.1016/j.tvjl.2014.07.028

Cited by 14 publications

(22 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Looking at the whole list of DEGs (Table S2) and focusing on CYP isoforms, it was found that their mRNA levels were either up-or downregulated after AFB1 exposure. Notably, CYP26B1, CYP27B1, and CYP3A4 (herein called CYP3A28, the orthologue of human CYP3A4, as demonstrated in [54]) were over-expressed, while nine other isoforms, including CYP1A1 and CYP1B1, were downregulated (Table 4). GSTs, a major class of conjugative drug metabolizing enzymes, were also significantly affected by AFB1 treatment.…”

Section: Whole-transcriptome Differential Expression Analysismentioning

confidence: 99%

Insights into Aflatoxin B1 Toxicity in Cattle: An In Vitro Whole-Transcriptomic Approach

Pauletto

Tolosi²,

Giantin³

et al. 2020

Toxins

View full text Add to dashboard Cite

Aflatoxins, and particularly aflatoxin B1 (AFB1), are toxic mycotoxins to humans and farm animal species, resulting in acute and chronic toxicities. At present, AFB1 is still considered a global concern with negative impacts on health, the economy, and social life. In farm animals, exposure to AFB1-contaminated feed may cause several untoward effects, liver damage being one of the most devastating ones. In the present study, we assessed in vitro the transcriptional changes caused by AFB1 in a bovine fetal hepatocyte-derived cell line (BFH12). To boost the cellular response to AFB1, cells were pre-treated with the co-planar PCB 3,3′,4,4′,5-pentachlorobiphenyl (PCB126), a known aryl hydrocarbon receptor agonist. Three experimental groups were considered: cells exposed to the vehicle only, to PCB126, and to PCB126 and AFB1. A total of nine RNA-seq libraries (three replicates/group) were constructed and sequenced. The differential expression analysis showed that PCB126 induced only small transcriptional changes. On the contrary, AFB1 deeply affected the cell transcriptome, the majority of significant genes being associated with cancer, cellular damage and apoptosis, inflammation, bioactivation, and detoxification pathways. Investigating mRNA perturbations induced by AFB1 in cattle BFH12 cells will help us to better understand AFB1 toxicodynamics in this susceptible and economically important food-producing species.

show abstract

Section: Whole-transcriptome Differential Expression Analysismentioning

confidence: 99%

Insights into Aflatoxin B1 Toxicity in Cattle: An In Vitro Whole-Transcriptomic Approach

Pauletto

Tolosi²,

Giantin³

et al. 2020

Toxins

View full text Add to dashboard Cite

show abstract

“…Cattle is one of the most important food-producing species, and the bovine CYP3A locus contains at least four genes. Three of them ( CYP3A28 , CYP3A38 and CYP3A48 ) have been identified and quantified in the liver [14,15]; the fourth one ( CYP3A24 ) is still considered a predicted sequence. Understanding bovine CYP3A regulation is interesting, because CYP3A induction is dramatically species-specific.…”

Section: Introductionmentioning

confidence: 99%

DNA elements for constitutive androstane receptor- and pregnane X receptor-mediated regulation of bovine CYP3A28 gene

et al. 2019

View full text Add to dashboard Cite

The regulation of cytochrome P450 3A (CYP3A) enzymes is established in humans, but molecular mechanisms of its basal and xenobiotic-mediated regulation in cattle are still unknown. Here, ~10 kbp of the bovine CYP3A28 gene promoter were cloned and sequenced, and putative transcription factor binding sites were predicted. The CYP3A28 proximal promoter (PP; -284/+71 bp) contained DNA elements conserved among species. Co-transfection of bovine nuclear receptors (NRs) pregnane X and constitutive androstane receptor (bPXR and bCAR) with various CYP3A28 promoter constructs into hepatoma cell lines identified two main regions, the PP and the distal fragment F3 (-6899/-4937 bp), that were responsive to bPXR (both) and bCAR (F3 fragment only). Site-directed mutagenesis and deletion of NR motif ER6, hepatocyte nuclear factor 1 (HNF-1) and HNF-4 binding sites in the PP suggested either the involvement of ER6 element in bPXR-mediated activation or the cooperation between bPXR and liver-enriched transcription factors (LETFs) in PP transactivation. A putative DR5 element within the F3 fragment was involved in bCAR-mediated PP+F3 transactivation. Although DNA enrichment by anti-human NR antibodies was quite low, ChIP investigations in control and RU486-treated BFH12 cells, suggested that retinoid X receptor α (RXRα) bound to ER6 and DR5 motifs and its recruitment was enhanced by RU486 treatment. The DR5 element seemed to be recognized mainly by bCAR, while no clear-cut results were obtained for bPXR. Present results point to species-differences in CYP3A regulation and the complexity of bovine CYP3A28 regulatory elements, but further confirmatory studies are needed.

show abstract

“…A fourth gene ( CYP3A24 ) has been additionally annotated but it probably refers to a pseudogene (Zancanella et al, 2010). In bovine liver, CYP3A28 gene is poorly expressed; however, CYP3A38 is the most abundant gene, followed by CYP3A48 (Zancanella et al, 2014). The coded proteins show a different behavior toward TST: CYP3A28 produces exclusively 6β‐OHTST, whereas CYP3A38 yields both 6β‐OH and 16β‐OH TST derivatives; conversely, CYP3A48 only marginally participates to TST metabolism, but it is involved in nifedipine oxidation (Giantin et al, 2019).…”

Section: Figurementioning

confidence: 99%

“…Hence, we speculate the 4‐OHMDZ production being attributable to CYP3A38 and CYP3A48 rather than CYP3A28. Noteworthy, CYP3A38 and CYP3A48 are the CYP3A most expressed genes in bovine liver (Zancanella et al, 2014), and the two bands cross‐reacting with the CYP3A1 polyclonal antibody (Figure ) might correspond to their coded proteins. A similar behavior was also reported when using an anti‐peptide antibody against bovine CYP3A4‐ like (Pegolo et al, 2010).…”

Section: Figurementioning

confidence: 99%

Midazolam oxidation in cattle liver microsomes: The role of cytochrome P450 3A

Nassi

Quintieri

Merlanti

et al. 2020

Vet Pharm & Therapeutics

View full text Add to dashboard Cite

In humans, the cytochrome P450 3A (CYP3A) subfamily is involved in midazolam (MDZ) biotransformation into 1′‐ and 4‐hydroxy metabolites, and the former serves as a probe for CYP3A catalytic activity. In veterinary species is still crucial to identify enzyme‐ and species‐specific CYP substrates; thus, the aim of this study was to characterize MDZ oxidation in cattle liver. A HPLC‐UV method was used to measure 1′‐ and 4‐hydroxy MDZ (1′‐ and 4‐OHMDZ, respectively) formation in cattle liver microsomes and assess the role of CYP3A by an immunoinhibition study. Moreover, MDZ hydroxylation was evaluated in 300 cattle liver samples and results were correlated with testosterone hydroxylation. Formation of both metabolites conformed to a single‐enzyme Michaelis–Menten kinetics. Values ofVmaxandKmwere 0.67 nmol/min/mg protein and 6.16 μM for 4‐OHMDZ, and 0.06 nmol/min/mg protein and 10.08 μM for 1′‐OHMDZ. An anti‐rat CYP3A1 polyclonal antibody inhibited up to 50% and 94% 1′‐ and 4‐OHMDZ formation, respectively. MDZ oxidation in liver microsomes was poorly correlated with testosterone hydroxylation. In conclusion, cattle metabolized MDZ to 1′‐OHMDZ and 4‐OHMDZ. The immunoinhibition results indicated a major contribution of CYP3As to 4‐OHMDZ formation and the involvement of other CYPs in 1′‐OHMDZ production, paving the way for further investigations.

show abstract

Absolute quantification and modulation of cytochrome P450 3A isoforms in cattle liver

Cited by 14 publications

References 38 publications

Insights into Aflatoxin B1 Toxicity in Cattle: An In Vitro Whole-Transcriptomic Approach

Insights into Aflatoxin B1 Toxicity in Cattle: An In Vitro Whole-Transcriptomic Approach

DNA elements for constitutive androstane receptor- and pregnane X receptor-mediated regulation of bovine CYP3A28 gene

Midazolam oxidation in cattle liver microsomes: The role of cytochrome P450 3A

Contact Info

Product

Resources

About