Application of in vitro Drug Metabolism Studies in Chemical Structure Optimization for the Treatment of Fibrodysplasia Ossificans Progressiva (FOP)

Excess inflammation and canonical BMP receptor (BMPR) signaling are coinciding hallmarks of the early stages of injury-induced endochondral heterotopic ossification (EHO), especially in the rare genetic disease fibrodysplasia ossificans progressiva (FOP). Multiple inflammatory signaling pathways can synergistically enhance BMP-induced Smad1/5/8 activity in multiple cell types, suggesting the importance of pathway crosstalk in EHO and FOP. Toll-like receptors (TLRs) and IL-1 receptors mediate many of the earliest injury-induced inflammatory signals largely via MyD88-dependent pathways. Thus, the hypothesis that MyD88-dependent signaling is required for EHO was tested in vitro and in vivo using global or Pdgfrα-conditional deletion of MyD88 in FOP mice. As expected, IL-1β or LPS synergistically increased Activin A (ActA)-induced phosphorylation of Smad 1/5 in fibroadipoprogenitors (FAPs) expressing Alk2R206H. However, conditional deletion of MyD88 in Pdgfrα-positive cells of FOP mice did not significantly alter the amount of muscle injury-induced EHO. Even more surprisingly, injury-induced EHO was not significantly affected by global deletion of MyD88. These studies demonstrate that MyD88-dependent signaling is dispensable for injury-induced EHO in FOP mice.

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Small and Simple, yet Sturdy: Conformationally Constrained Peptides with Remarkable Properties

International Journal of Molecular Sciences ◽

10.3390/ijms22041611 ◽

2021 ◽

Vol 22 (4) ◽

pp. 1611

Author(s):

Krištof Bozovičar ◽

Tomaž Bratkovič

Keyword(s):

Chemical Space ◽

Structure Optimization ◽

Peptide Chain ◽

Conformationally Constrained ◽

Drug Candidates ◽

Conformational Constraints ◽

Macrocyclic Peptides ◽

Constrained Peptides ◽

Sheer Size

The sheer size and vast chemical space (i.e., diverse repertoire and spatial distribution of functional groups) underlie peptides’ ability to engage in specific interactions with targets of various structures. However, the inherent flexibility of the peptide chain negatively affects binding affinity and metabolic stability, thereby severely limiting the use of peptides as medicines. Imposing conformational constraints to the peptide chain offers to solve these problems but typically requires laborious structure optimization. Alternatively, libraries of constrained peptides with randomized modules can be screened for specific functions. Here, we present the properties of conformationally constrained peptides and review rigidification chemistries/strategies, as well as synthetic and enzymatic methods of producing macrocyclic peptides. Furthermore, we discuss the in vitro molecular evolution methods for the development of constrained peptides with pre-defined functions. Finally, we briefly present applications of selected constrained peptides to illustrate their exceptional properties as drug candidates, molecular recognition probes, and minimalist catalysts.

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Proteomic profiling of murine biliary-derived hepatic organoids and their capacity for drug disposition, bioactivation and detoxification

Archives of Toxicology ◽

10.1007/s00204-021-03075-3 ◽

2021 ◽

Author(s):

Lawrence Howell ◽

Rosalind E. Jenkins ◽

Stephen Lynch ◽

Carrie Duckworth ◽

B. Kevin Park ◽

...

Keyword(s):

Cytochrome P450 ◽

Drug Metabolism ◽

Rna Polymerase Ii ◽

Liver Tissue ◽

Drug Disposition ◽

Multiple Drug ◽

Proteomic Profiling ◽

Cytochrome P450 3A ◽

Drug Induced

AbstractHepatic organoids are a recent innovation in in vitro modeling. Initial studies suggest that organoids better recapitulate the liver phenotype in vitro compared to pre-existing proliferative cell models. However, their potential for drug metabolism and detoxification remains poorly characterized, and their global proteome has yet to be compared to their tissue of origin. This analysis is urgently needed to determine what gain-of-function this new model may represent for modeling the physiological and toxicological response of the liver to xenobiotics. Global proteomic profiling of undifferentiated and differentiated hepatic murine organoids and donor-matched livers was, therefore, performed to assess both their similarity to liver tissue, and the expression of drug-metabolizing enzymes and transporters. This analysis quantified 4405 proteins across all sample types. Data are available via ProteomeXchange (PXD017986). Differentiation of organoids significantly increased the expression of multiple cytochrome P450, phase II enzymes, liver biomarkers and hepatic transporters. While the final phenotype of differentiated organoids is distinct from liver tissue, the organoids contain multiple drug metabolizing and transporter proteins necessary for liver function and drug metabolism, such as cytochrome P450 3A, glutathione-S-transferase alpha and multidrug resistance protein 1A. Indeed, the differentiated organoids were shown to exhibit increased sensitivity to midazolam (10–1000 µM) and irinotecan (1–100 µM), when compared to the undifferentiated organoids. The predicted reduced activity of HNF4A and a resulting dysregulation of RNA polymerase II may explain the partial differentiation of the organoids. Although further experimentation, optimization and characterization is needed relative to pre-existing models to fully contextualize their use as an in vitro model of drug-induced liver injury, hepatic organoids represent an attractive novel model of the response of the liver to xenobiotics. The current study also highlights the utility of global proteomic analyses for rapid and accurate evaluation of organoid-based test systems.

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Crypt Organoid Culture as an In Vitro Model in Drug Metabolism and Cytotoxicity Studies

Drug Metabolism and Disposition ◽

10.1124/dmd.117.075945 ◽

2017 ◽

Vol 45 (7) ◽

pp. 748-754 ◽

Cited By ~ 18

Author(s):

Wenqi Lu ◽

Eva Rettenmeier ◽

Miles Paszek ◽

Mei-Fei Yueh ◽

Robert H. Tukey ◽

...

Keyword(s):

Drug Metabolism ◽

In Vitro Model ◽

Organoid Culture ◽

Cytotoxicity Studies ◽

Vitro Model

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In vitro drug metabolism by C-terminally truncated human flavin-containing monooxygenase 3

Biochemical Pharmacology ◽

10.1016/j.bcp.2011.11.029 ◽

2012 ◽

Vol 83 (4) ◽

pp. 551-558 ◽

Cited By ~ 31

Author(s):

Gianluca Catucci ◽

Gianfranco Gilardi ◽

Lars Jeuken ◽

Sheila J. Sadeghi

Keyword(s):

Drug Metabolism

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Predicting Organ Toxicity Using in Vitro Bioactivity Data and Chemical Structure

Chemical Research in Toxicology ◽

10.1021/acs.chemrestox.7b00084 ◽

2017 ◽

Vol 30 (11) ◽

pp. 2046-2059 ◽

Cited By ~ 23

Author(s):

Jie Liu ◽

Grace Patlewicz ◽

Antony J. Williams ◽

Russell S. Thomas ◽

Imran Shah

Keyword(s):

Chemical Structure ◽

In Vitro Bioactivity ◽

Organ Toxicity

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Hierarchy of evidence in interpretation of clinical significance of drug interactions

Medicinski pregled ◽

10.2298/mpns1202045n ◽

2012 ◽

Vol 65 (1-2) ◽

pp. 45-49

Author(s):

Bozana Nikolic ◽

Miroslav Savic

Keyword(s):

Drug Metabolism ◽

Drug Interactions ◽

Clinical Significance ◽

Health Professionals ◽

Molecular Entity ◽

Population Pharmacokinetic ◽

Pharmacokinetic Studies ◽

Potential Interactions

Introduction. Since drug interactions may result in serious adverse effects or failure of therapy, it is of huge importance that health professionals base their decisions about drug prescription, dispensing and administration on reliable research evidence, taking into account the hierarchy of data sources for evaluation. Clinical Significance of Potential Interactions - Information Sources. The sources of data regarding drug interactions are numerous, beginning with various drug reference books. However, they are far from uniformity in the way of choosing and presenting putative clinically relevant interactions. Clinical Significance of Potential Interactions - Interpretation of Information. The difficulties in interpretation of drug interactions are illustrated through the analysis of a published example involving assessment made by two different groups of health professionals. Systematic Evaluation of Drug-Drug Interaction. The potential for interactions is mainly investigated before marketing a drug. Generally, the in vitro, followed by in vivo studies are to be performed. The major metabolic pathways involved in the metabolism of a new molecular entity, as well as the potential of induction of human enzymes involved in drug metabolism are to be examined. In the field of interaction research it is possible to make use of the population pharmacokinetic studies as well as of the pharmacodynamic assessment, and also the postregistration monitoring of the reported adverse reactions and other literature data. Conclusion. In vitro and in vivo drug metabolism and transport studies should be conducted to elucidate the mechanisms and potential for drug-drug interactions. The assessment of their clinical significance should be based on well-defined and validated exposure-response data.

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Inhibition of Hepatic Microsomal Drug Metabolism by the Hydrazines Ro 4-4602, MK 486, and Procarbazine Hydrochloride

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y72-105 ◽

1972 ◽

Vol 50 (7) ◽

pp. 721-724 ◽

Cited By ~ 4

Author(s):

Norman R. Bade ◽

Stuart M. MacLeod ◽

Kenneth W. Renton

Keyword(s):

Drug Interaction ◽

Drug Metabolism ◽

Sleeping Time ◽

Hydrazine Derivatives ◽

Significant Drug Interaction ◽

Microsomal Drug Metabolism ◽

Clinically Significant ◽

Hepatic Biotransformation

Preliminary experiments were undertaken to examine the effect of three hydrazine derivatives, viz. Ro 4-4602, MK 486, and procarbazine hydrochloride, on hepatic microsomal drug metabolism in rats. All three compounds when given as pretreatment significantly prolonged pentobarbital sleeping time. In vitro, the hepatic microsomal N-demethylation of aminopyrine was inhibited. It is concluded that all three drugs are possible sources of clinically significant drug interaction when administered in combination with other agents which undergo hepatic biotransformation.

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