Title:

In vitro metabolism study of the compounds with defined activity in the central nervous system

Author:

Kubowicz-Kwaśny, Paulina

Subject:

biotransformation ; enzymatic inhibition ; alternative methods to study metabolism ; cytochrome P450

Abstract:

Studies on the biotransformation of drugs were carried out using laboratory animals from the eighties of the last century. According to the European Centre of the Validation of Alternative Methods in various tests up to 10 million animals per year are killed, more than 60 % of these - in the preclinical phase of drug testing. Apart from humanitarian reasons, economic considerations, time and only 50 % chance to reflect the results obtained in animal models in later studies involving people are the other aspects against in vivo studies . Especially in the early stages of drug development alternative methods are more relevant and appropriate . These models meet the criteria introduced by Russell and Burch called 3R criteria (replacement, reduction, refinement). In silico and in vitro biotransformation studies, which include research using microorganisms and liver subcellular fractions are complient with 3R principle.The project conducted within the doctoral thesis applied research on the biotransformation of twelve selected structure obtained in the Department of Bioorganic Chemistry, Chair Organic Chemistry and in the Department of Medicinal Chemistry, Chair Pharmaceutical Chemistry, Faculty of Pharmacy, Jagiellonian University Medical College. Selected structures had proven activity in the central nervous system in animal models. Among the compounds investigated were aminoalkan ; ol derivatives (1(a-c)-3) with analgesic and anticonvulsant activity, derivatives of aripiprazole (4-7) endowed with antipsychotic activity and derivatives of zolpidem (8-10) with hypnotic and antipsychotic activity. Biotransformation studies were carried out using the in silico (MetaSite software) and in vitro models. Microbial model (3 different species of filamentous fungus Cunninghamella elegans, echinulata, blakesleeana) as well as liver microsomes model (mouse, rat, human) and S9 fraction were used in in vitro studies. The progress of the reaction was monitored using LC/MS method.Based on the obtained results we were able to define the biotransformation pathways, structure of the metabolites of the tested compounds (1(a-c)-10) and enzymes involved in their formation. Moreover the metabolic stability, half-life t0.5 and internal clearance Clint were determined. Interspecies differences in the rate of metabolism and biotransformation pathways were identified in case of the compound 7. Drug-drug interactions of the major CYP450 isoenzymes were determined for compound 2, which proved to be a mixed inhibitor of CYP2D6 (Ki = 1.701 μM).Obtained results enabled us to determine some lipophilicity – stability dependence in case of tested compounds. Compounds 2, 3 and 8-10 were characterized by high metabolic stability and had lipophilicity in the range of log P 2.16-3.0, while comp ; ounds with log P > 3 had lower stability. Compounds with log P > 4 (4 and 5) were characterized by the N-dealcylation, O-dealcylation and less frequently C-dealcylation manner of biotransformation, while structures with lower log P (1(a-c),-3,7,9) preferred oxidative metabolism not associated with the degradation of the structure.The obtained results are very applicable. They allowed us to choose the most stable compounds (6,8,10), which contributes to the rational selection of test connections with a defined activity in the central nervous system for further testing. Moreover, predicting moieties susceptible to the biotransformation enzymes in the unstable compounds (1(a-c),4,5,7) contribute to make structural modifications to create more stable connections.

Place of publishing:

Kraków

Level of degree:

2 - studia doktoranckie

Degree discipline:

farmacja

Degree grantor:

Wydział Farmaceutyczny

Promoter:

Pękala, Elżbieta

Date:

2016

Date issued:

2016

Type:

Praca doktorska

Call number:

ZB-125998

Language:

pol

Access rights:

nieograniczony

×

Citation

Citation style: