Evaluation of MTBH, a novel hesperetin derivative, on the activity of hepatic cytochrome P450 isoform in vitro and in vivo using a cocktail method by HPLC-MS/MS

Xenobiotica ◽  
2021 ◽  
pp. 1-14
Author(s):  
Yan Qin ◽  
Haijun Dong ◽  
Jiayin Sun ◽  
Yilong Zhang ◽  
Jun Li ◽  
...  
1998 ◽  
Vol 157 (1) ◽  
pp. 63-70 ◽  
Author(s):  
JM Wilson ◽  
MM Vijayan ◽  
CJ Kennedy ◽  
GK Iwama ◽  
TW Moon

We report for the first time that beta-naphthoflavone (BNF) abolishes ACTH stimulation of cortisol production in rainbow trout (Oncorhynchus mykiss). There was significantly higher hepatic cytochrome P450 content and ethoxyresorufin O-de-ethylase and uridine-5'-diphosphoglucuronic acid transferase activities in BNF-treated fish than in sham-treated controls. BNF did not significantly affect either plasma turnover or tissue distribution of [3H]cortisol-derived radioactivity. Hepatic membrane fluidity and hepatocyte capacity for cortisol uptake were not altered by BNF as compared with the sham-treated fish. These results taken together suggest that BNF does not affect cortisol-clearance mechanisms in trout. A 3 min handling disturbance period elicited a plasma cortisol response in the sham-treated fish; however, the response in the BNF-treated fish was muted and significantly lower than in the sham fish. This in vivo response corroborates the lack of interrenal sensitivity to ACTH in vitro in the BNF-treated fish, suggesting that BNF affects the ACTH pathway in trout. Our results suggest the possibility that cytochrome P450-inducing compounds may affect cortisol dynamics by decreasing interrenal responsiveness to ACTH stimulation in fish, thereby impairing the physiological responses that are necessary for the animal to cope with the stressor.


Planta Medica ◽  
2014 ◽  
Vol 80 (07) ◽  
pp. 561-567 ◽  
Author(s):  
Sang-Bum Kim ◽  
In-Soo Yoon ◽  
Kyu-Sang Kim ◽  
Sung-Jun Cho ◽  
Yeong Kim ◽  
...  

1994 ◽  
Vol 72 (02) ◽  
pp. 313-317 ◽  
Author(s):  
P Savi ◽  
J Combalbert ◽  
C Gaich ◽  
M-C Rouchon ◽  
J-P Maffrand ◽  
...  

SummaryClopidogrel and ticlopidine are two well known selective anti-ADP agents which are inactive in vitro and must be administered in vivo to fully exhibit their antiaggregating and antithrombotic effects. Since previous studies have clearly demonstrated that the activation steps take place in the liver, we examined the effect of specific induction or inhibition of cytochrome P450 subfamilies on the antiaggregating activity of clopidogrel. SKF 525-A, a global cytochrome P450 inhibitor, dramatically decreased the antiaggregating effect of clopidogrel, therefore indicating that cytochrome P450 enzymes are involved in the hepatic activation of clopidogrel. The efficacy of clopidogrel was increased in animals pretreated with 3-methylcholanthrene and (3-naphthoflavone, indicating that the cytochrome P450-1A subfamily pathway was mainly involved in the activating metabolism of clopidogrel. The use of specific antibodies directed against the various cytochrome P450 subfamilies ascertained this observation.


2011 ◽  
Vol 1 (1) ◽  
pp. 4 ◽  
Author(s):  
Hansen W. Murcia ◽  
Gonzalo J. Díaz ◽  
Sandra Milena Cepeda

Cytochrome P450 enzymes (CYP) are a group of monooxygenases able to biotransform several kinds of xenobiotics including aflatoxin B1 (AFB1), a highly toxic mycotoxin. These enzymes have been widely studied in humans and others mammals, but there is not enough information in commercial poultry species about their biochemical characteristics or substrate specificity. The aim of the present study was to identify CYPs from avian liver microsomes with the use of prototype substrates specific for human CYP enzymes and AFB1. Biochemical characterization was carried out in vitro and biotransformation products were detected by high-performance liquid chromatography (HPLC). Enzymatic constants were calculated and comparisons between turkey, duck, quail and chicken activities were done. The results demonstrate the presence of four avian ortholog enzyme activities possibly related with a CYP1A1, CYP1A2, CYP2A6 (activity not previously identified) and CYP3A4 poultry orthologs, respectively. Large differences in enzyme kinetics specific for prototype substrates were found among the poultry species studied. Turkey liver microsomes had the highest affinity and catalytic rate for AFB1 whereas chicken enzymes had the lowest affinity and catalytic rate for the same substrate. Quail and duck microsomes showed intermediate values. These results correlate well with the known in vivo sensitivity for AFB1 except for the duck. A high correlation coefficient between 7-ethoxyresorufin-Odeethylase (EROD) and 7-methoxyresorufin- O-deethylase (MROD) activities was found in the four poultry species, suggesting that these two enzymatic activities might be carried out by the same enzyme. The results of the present study indicate that four prototype enzyme activities are present in poultry liver microsomes, possibly related with the presence of three CYP avian orthologs. More studies are needed in order to further characterize these enzymes.


Sign in / Sign up

Export Citation Format

Share Document