𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Use of physiologically based pharmacokinetic models to evaluate the impact of intestinal glucuronide hydrolysis on the pharmacokinetics of aglycone

✍ Scribed by Baojian Wu


Publisher
John Wiley and Sons
Year
2012
Tongue
English
Weight
1019 KB
Volume
101
Category
Article
ISSN
0022-3549

No coin nor oath required. For personal study only.

✦ Synopsis


Drug elimination via glucuronidation pathway is a complex process involving glucuronide excretion. Glucuronide excreted into the gut lumen either directly from the enterocytes or from the hepatobiliary route can be recovered back to the precursor (aglycone) through bacteria-mediated hydrolysis. As a result, the pharmacokinetics [e.g., plasma terminal half-life (T 1/2 )] of aglycone might be altered. Here, impact of intestinal glucuronide hydrolysis on the pharmacokinetics of aglycone is evaluated using physiologically based pharmacokinetic (PBPK) models with liver and/or intestine as eliminating organs. It is found that compared with its absence, the presence of intestinal glucuronide hydrolysis leads to increases in the oral systemic bioavailability (F sys ) of aglycone. The magnitude of fold increase is positively correlated with the level of metabolism, as metabolic clearance mainly contributes to recycled amount of glucuronide. Although F sys is independent of the glucuronide efflux in a traditional model and a segregated-flow model of the intestine, dependence of F sys on the glucuronide efflux can be observed in a segmental segregated-flow model of the intestine and whole-body PBPK models. Interestingly, when the ratio of apical versus basolateral efflux intrinsic clearances (of glucuronide) is fixed, their effects on the intestinal bioavailability and F sys cease to exist. In addition, glucuronide hydrolysis can lead to a significantly delayed elimination of the aglycone as evidenced by a prolonged (e.g., a 2.1-fold increase) T 1/2 . Surprisingly, when a pharmacokinetic profile for aglycone is simulated with a flat terminal portion (a reflection of the experimental observations), changes in the aglycone bioavailabilities are limited (i.e., ≀1.3-fold). In conclusion, this study explores the possible role of intestinal glucuronide hydrolysis in the disposition of aglycone via simulations utilizing various PBPK models. The mechanistic observations should be helpful to better understand the complex glucuronidation in vivo.


πŸ“œ SIMILAR VOLUMES


An evaluation of the utility of physiolo
✍ Neil Parrott; Nicolas Paquereau; Philippe Coassolo; Thierry LavΓ© πŸ“‚ Article πŸ“… 2005 πŸ› John Wiley and Sons 🌐 English βš– 494 KB

Generic physiologically-based models of pharmacokinetics were evaluated for early drug discovery. Plasma profiles after intravenous and oral dosing were simulated in rat for 68 compounds from six chemical classes. Input data consisted of structure based predictions of lipophilicity, ionization, and

A priori prediction of tissue:plasma par
✍ Patrick Poulin; Frank-Peter Theil πŸ“‚ Article πŸ“… 2000 πŸ› John Wiley and Sons 🌐 English βš– 374 KB πŸ‘ 3 views

The tissue:plasma (P t:p ) partition coefficients (PCs) are important drugspecific input parameters in physiologically based pharmacokinetic (PBPK) models used to estimate the disposition of drugs in biota. Until now the use of PBPK models in early stages of the drug discovery process was not possib

On the use of finite-difference and neur
✍ A. Hani; S. Lallahem; J. Mania; L. Djabri πŸ“‚ Article πŸ“… 2006 πŸ› John Wiley and Sons 🌐 English βš– 288 KB πŸ‘ 1 views

## Abstract The purpose of this study is to include expert knowledge as one part of the modelling system and thereby offer the chance to create a productive interactive system between expert, mathematical model, ASM, and artificial neural networks (ANNs). An attempt to determine outflow‐influencing

Hepatobiliary disposition of valproic ac
✍ C L Booth; G M Pollack; K L Brouwer πŸ“‚ Article πŸ“… 1996 πŸ› John Wiley and Sons 🌐 English βš– 271 KB

with phenobarbital-associated impairment of canalicu-Previous work in this laboratory has suggested that lar egress of some organic anions. This work further supthe nonlinear disposition of valproic acid (VPA) in the ports the utility of pharmacokinetic modeling in: (1) derat may be due to nonlinear