Cytochrome P450-depedent Drug Oxidation Activity of Liver Microsomes from Microminipigs, A Possible New Animal Model for Humans in Non-clinical Studies

doi:10.2133/dmpk.24.404

Drug Metabolism and Pharmacokinetics

Volume 24, Issue 4, 2009, Pages 404-408

https://doi.org/10.2133/dmpk.24.404 Get rights and content

Summary:

Small minipigs (Bland name, Micromini Pig; registered as a novel variety of pig in the Japanese Ministry of Agriculture, Forestry and Fisheries) were developed with the aim of non-clinical pharmacological/toxicological use. They were principally mated with < 10 kg body weight at 7 months-old resulting in good handling. Cytochrome P450 (P450)-and flavin-containing monooxygenases (FMO)-dependent drug oxidation activity of liver microsomes prepared from male Microminipigs (8 months-old) was compared with thatfor pooled dogs, monkeys, and humans. High P450 2D-dependent bufuralol 1′-hydroxylation and FMO-dependent benzydamine N-oxygenation activity was observed in liver microsomes from Microminipigs. Typical P450 1A, 2B, 2C, 2E, and 3A-dependent drug oxidation activity was also seen in Microminipigs. However, occasional differences might give undetected low P450 2A-dependent coumarin 7-hydroxylation in Microminipigs at 8-months-old, in contrast to liver microsomes from one 10-days-old Microminipis and commercially available pooled minipigs which had low but detectable coumarin 7-hydroxylation activity. The present results suggest that there is some overlap in Microminipig and human P450 substrate specificity. These findings should provide important information for greater understanding of drug metabolism in Microminipigs, as an experimental animal model for non-clinical use.

References (18)

H. Yamazaki et al.
Roles of NADPH-P450 reductase and apo-and holo-cytochrome b₅ on xenobiotic oxidations catalyzed by 12 recombinant human cytochrome P450s expressed in membranes of Escherichia coli
Protein Expr. Purif.
(2002)
T. Omura et al.
The carbon monoxide-binding pigment of liver microsomes I. Evidence for its hemoprotein nature
J. Biol. Chem.
(1964)
H. Yamazaki et al.
Catalytic roles of rat and human cytochrome P450 2A enzymes in testosterone 7a-and coumarin 7-hydroxylations
Biochem. Pharmacol.
(1994)
O. Svendsen
The minipig in toxicology
Exp. Toxicol. Pathol
(2006)
J.H. Lin
Species similarities and differences in pharmacokinetics
Drug Metab. Dispos.
(1995)
P. Anzenbacher et al.
Presence and activity of cytochrome P450 isoforms in minipig liver microsomes. Comparison with human liver samples
Drug Metab. Dispos.
(1998)
D.D. Shen et al.
Enzyme-catalyzed processes of first-pass hepatic and intestinal drug extraction
Adv. Drug Deliv. Rev.
(1997)
D.A. Smith
Species differences in metabolism and pharmacokinetics: are we close to an understanding?
Drug Metab. Rev.
(1991)
F.P. Guengerich
Cytochrome P450 and chemical toxicology
Chem. Res. Toxicol.
(2008)

There are more references available in the full text version of this article.

Cited by (43)

Newly identified cytochrome P450 3A genes of tree shrews and pigs are expressed and encode functional enzymes
2023, Comparative Biochemistry and Physiology Part - C: Toxicology and Pharmacology
Novel cytochrome P450 3A5 (CYP3A5) cDNA in tree shrews (which are non-rodent primate-like species) and pig CYP3A227 cDNA were identified, along with known pig CYP3A22, CYP3A29, and CYP3A46 cDNAs. All five cDNAs contained open reading frames encoding a polypeptide of 503 amino acids that shared high sequence identity (72–78 %) with human CYP3A4 and were more closely related to human CYP3As than rat CYP3As by phylogenetic analysis. CYP3A5 was the only CYP3A in the tree shrew genome, but pig CYP3A genes formed a CYP3A gene cluster in the genomic region corresponding to that of human CYP3A genes. Tree shrew CYP3A5 mRNA was predominantly expressed in liver and small intestine, among the tissues analyzed, whereas pig CYP3A227 mRNA was most abundantly expressed in jejunum, followed by liver. Metabolic assays established that tree shrew CYP3A5 and pig CYP3A proteins heterologously expressed in Escherichia coli metabolized typical human CYP3A4 substrates nifedipine and midazolam. These results suggest that novel tree shrew CYP3A5 and pig CYP3A227 were functional enzymes able to metabolize human CYP3A4 substrates in liver and small intestine, similar to human CYP3A4, although pig CYP3A227 mRNA was minimally expressed in all tissues analyzed.
Oral-fecal mycobiome in wild and captive cynomolgus macaques (Macaca fascicularis)
2020, Fungal Genetics and Biology
Cynomolgus macaque (Macaca fascicularis) is currently a common animal model for biomedical research. The National Primate Research Center of Thailand, Chulalongkorn University (NPRCT-CU) translocated wild-borne macaques to reared colony for research purposes. At present, no studies focus on fungal microbiome (Mycobiome) of this macaque. The functional roles of mycobiome and fungal pathogens have not been elucidated. Thus, this study aimed to investigate and compare oral and fecal mycobiome between wild and captive macaques by using high-throughput sequencing on internal transcribed spacer 2 (ITS2) rDNA. The results showed that the mycobiome of wild macaque has greater alpha diversity. The fecal mycobiome has more limited alpha diversity than those in oral cavity. The community is mainly dominated by saprophytic yeast in Kasachstania genus which is related to aiding metabolic function in gut. The oral microbiome of most captive macaques presented the Cutaneotrichosporon suggesting the fungal transmission through skin-oral contact within the colony. The potential pathogens that would cause harmful transmission in reared colonies were not found in either group of macaques but the pathogen prevention and animal care is still important to be concerned. In conclusion, the results of gut mycobiome analysis in Thai cynomolgus macaques provide us with the basic information of oral and fecal fungi and for monitoring macaque's health status for animal care of research use.
Microminipig: A suitable animal model to estimate oral absorption of sustained-release formulation in humans
2020, International Journal of Pharmaceutics
We investigated the gastrointestinal absorption characteristics of oral sustained-release formulations in microminipigs, dogs, and monkeys in order to clarify the similarities in absorption properties between these animals and humans. Time profiles of oral absorption of nifedipine and valproic acid were calculated from the plasma concentration–time profiles of the drugs by a deconvolution method. The curves for both drugs in microminipigs were close to or slightly higher than those in humans, whereas those in monkeys were lower. Furthermore, the plasma concentration–time profiles of the drugs were subjected to non-compartmental analysis. The fractions of a dose absorbed into the portal vein (FaFg) in microminipigs ranged from 50 to 100% of the human values, whereas those in monkeys were less than half the human values. In addition, the other absorption-related parameters for the sustained-release formulation in microminipigs, as well as monkeys, were comparable to those in humans. In conclusion, the oral absorption properties of microminipigs and humans were similar regarding the sustained-release formulations. Therefore, microminipig is a suitable animal model to estimate the oral absorption of sustained-release formulations in humans.
Characterization of microminipig as a laboratory animal for pharmacological study by analyzing bepridil-induced cardiovascular responses
2020, Journal of Pharmacological Sciences
Since microminipig is becoming attractive model for various cardiac electropharmacological applications, which may meet consideration of 3Rs. We characterized microminipigs by analyzing how multi-ionic channel inhibitor bepridil may affect their in situ hearts in comparison with dogs. Bepridil in doses of 0.3 and 3.0 mg/kg were intravenously administered over 10 min under halothane anesthesia (n = 4). Microminipigs may be less sensitive for I_CaT inhibition of bepridil, whereas they are more responsive to I_Na, I_Kr and I_Ks suppression than dogs. This information would help predict cardiovascular effects of a drug in patients with the remodeled hearts having similar electrophysiological profile to microminipigs.
Characterization of microminipigs as an in vivo experimental model for cardiac safety pharmacology
2017, Journal of Pharmacological Sciences
We pharmacologically characterized microminipigs as an in vivo experimental model by assessing cardiovascular effects of pilsicainide, verapamil and E-4031, which can preferentially inhibit cardiac Na⁺, Ca²⁺ and K⁺ channels, respectively. Intravenous infusion of 1 mg/kg of pilsicainide (n = 4), 0.1 mg/kg of verapamil (n = 4) and 0.01 followed by 0.1 mg/kg of E-4031 (n = 5) over 10 min decreased the heart rate, mean blood pressure and ventricular contractility. Moreover, pilsicainide prolonged the PR interval, QRS width and QTc; verapamil prolonged the PR interval, but shortened the QRS width and QTc; and E-4031 prolonged the QTc, whereas no substantial change was detected in the PR interval or QRS width. Peak plasma concentrations of pilsicainide, verapamil and E-4031 in microminipigs were 1.7–4.8 times higher than those expected in humans and dogs, possibly due to smaller effective volume of drug distribution. The extent of the drug-induced cardiovascular responses was generally greater in microminipigs than in humans and dogs, which could be explained by the following possibilities; namely unique pharmacokinetic profile, less great reflex-mediated increase of sympathetic tone and/or smaller repolarization reserve in microminipigs. These information may make it feasible to apply this new-type animal to a tool for assessing cardiac safety profiles of new chemical entities.
Sex differences in constitutive mRNA levels of CYP2B22, CYP2C33, CYP2C49, CYP3A22, CYP3A29 and CYP3A46 in the pig liver: Comparison between Meishan and Landrace pigs
2016, Drug Metabolism and Pharmacokinetics
Breed and sex differences in hepatic mRNA levels of cytochrome P450 (CYP) isoforms (CYP2B22, CYP2C33, CYP2C49, CYP3A22, CYP3A29 and CYP3A46) were examined in 5-month-old Meishan, Landrace, and their crossbred F₁ (LM and ML) pigs. Serum testosterone levels in male Meishan, LM, and ML pigs were 2.5–3.5-fold higher than in Landrace pigs. CYP3A46 mRNA was breed-specifically detected only in Landrace, LM, and ML pigs. In Meishan, LM, and ML pigs only, male-predominant expressions of CYP2B22, CYP2C33, CYP2C49 and CYP3A29 mRNAs were observed; CYP3A22 mRNA expression showed the opposite pattern. Male-dominant mRNA expression was also observed in LM and ML pigs for CYP3A46. The sex differences in CYP mRNA levels in Meishan pigs disappeared when males were castrated and were restored by testosterone propionate (TP) administration to the castrated males. In Landrace pigs, TP administration to castrated males and intact females significantly increased the levels of CYP2B22, CYP2C33, and CYP3A46 mRNAs. Immature (1-month-old) pigs showed no breed or sex differences in CYP mRNA expressions. The results demonstrated that androgen is an important determinant of sex-associated expression of several CYPs and suggested that breed differences in sex-associated expression could be caused by differences in serum androgen level and by other genetic traits.

View all citing articles on Scopus

View full text

Article preview

Drug Metabolism and Pharmacokinetics

Summary:

References (18)

Roles of NADPH-P450 reductase and apo-and holo-cytochrome b₅ on xenobiotic oxidations catalyzed by 12 recombinant human cytochrome P450s expressed in membranes of Escherichia coli

Protein Expr. Purif.

The carbon monoxide-binding pigment of liver microsomes I. Evidence for its hemoprotein nature

J. Biol. Chem.

Catalytic roles of rat and human cytochrome P450 2A enzymes in testosterone 7a-and coumarin 7-hydroxylations

Biochem. Pharmacol.

The minipig in toxicology

Exp. Toxicol. Pathol

Species similarities and differences in pharmacokinetics

Drug Metab. Dispos.

Presence and activity of cytochrome P450 isoforms in minipig liver microsomes. Comparison with human liver samples

Drug Metab. Dispos.

Enzyme-catalyzed processes of first-pass hepatic and intestinal drug extraction

Adv. Drug Deliv. Rev.

Species differences in metabolism and pharmacokinetics: are we close to an understanding?

Drug Metab. Rev.

Cytochrome P450 and chemical toxicology

Chem. Res. Toxicol.

Cited by (43)

Newly identified cytochrome P450 3A genes of tree shrews and pigs are expressed and encode functional enzymes

Oral-fecal mycobiome in wild and captive cynomolgus macaques (Macaca fascicularis)

Microminipig: A suitable animal model to estimate oral absorption of sustained-release formulation in humans

Characterization of microminipig as a laboratory animal for pharmacological study by analyzing bepridil-induced cardiovascular responses

Characterization of microminipigs as an in vivo experimental model for cardiac safety pharmacology

Sex differences in constitutive mRNA levels of CYP2B22, CYP2C33, CYP2C49, CYP3A22, CYP3A29 and CYP3A46 in the pig liver: Comparison between Meishan and Landrace pigs

NoteCytochrome P450-depedent Drug Oxidation Activity of Liver Microsomes from Microminipigs, A Possible New Animal Model for Humans in Non-clinical Studies

Summary:

Protein Expr. Purif.

J. Biol. Chem.

Biochem. Pharmacol.

Exp. Toxicol. Pathol

Species similarities and differences in pharmacokinetics

Drug Metab. Dispos.

Presence and activity of cytochrome P450 isoforms in minipig liver microsomes. Comparison with human liver samples

Drug Metab. Dispos.

Enzyme-catalyzed processes of first-pass hepatic and intestinal drug extraction

Adv. Drug Deliv. Rev.

Species differences in metabolism and pharmacokinetics: are we close to an understanding?

Drug Metab. Rev.

Cytochrome P450 and chemical toxicology

Chem. Res. Toxicol.

Note
Cytochrome P450-depedent Drug Oxidation Activity of Liver Microsomes from Microminipigs, A Possible New Animal Model for Humans in Non-clinical Studies