Considerations for Improving Metabolism Predictions for In Vitro to In Vivo Extrapolation

Moreau, Marjory; Mallick, Pankajini; Smeltz, Marci; Haider, Saad; Nicolas, Chantel I.; Pendse, Salil N.; Leonard, Jeremy A.; Linakis, Matthew W.; McMullen, Patrick D.; Clewell, Rebecca A.; Clewell, Harvey J.; Yoon, Miyoung

doi:10.3389/ftox.2022.894569

Cited by 14 publications

(14 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The metabolic assay examined here (suspension of primary human hepatocytes pooled from multiple donors) is just one of many in vitro metabolism methods available ( Moreau et al, 2022 ). However, primary hepatocyte suspensions are a well characterized method ( Shibata et al, 2002 ; Gouliarmou et al, 2018 ; Bowman 2019 ).…”

Section: Discussionmentioning

confidence: 99%

Identifying xenobiotic metabolites with in silico prediction tools and LCMS suspect screening analysis

Boyce

Favela²,

Bonzo³

et al. 2023

Front. Toxicol.

View full text Add to dashboard Cite

Understanding the metabolic fate of a xenobiotic substance can help inform its potential health risks and allow for the identification of signature metabolites associated with exposure. The need to characterize metabolites of poorly studied or novel substances has shifted exposure studies towards non-targeted analysis (NTA), which often aims to profile many compounds within a sample using high-resolution liquid-chromatography mass-spectrometry (LCMS). Here we evaluate the suitability of suspect screening analysis (SSA) liquid-chromatography mass-spectrometry to inform xenobiotic chemical metabolism. Given a lack of knowledge of true metabolites for most chemicals, predictive tools were used to generate potential metabolites as suspect screening lists to guide the identification of selected xenobiotic substances and their associated metabolites. Thirty-three substances were selected to represent a diverse array of pharmaceutical, agrochemical, and industrial chemicals from Environmental Protection Agency’s ToxCast chemical library. The compounds were incubated in a metabolically-active in vitro assay using primary hepatocytes and the resulting supernatant and lysate fractions were analyzed with high-resolution LCMS. Metabolites were simulated for each compound structure using software and then combined to serve as the suspect screening list. The exact masses of the predicted metabolites were then used to select LCMS features for fragmentation via tandem mass spectrometry (MS/MS). Of the starting chemicals, 12 were measured in at least one sample in either positive or negative ion mode and a subset of these were used to develop the analysis workflow. We implemented a screening level workflow for background subtraction and the incorporation of time-varying kinetics into the identification of likely metabolites. We used haloperidol as a case study to perform an in-depth analysis, which resulted in identifying five known metabolites and five molecular features that represent potential novel metabolites, two of which were assigned discrete structures based on in silico predictions. This workflow was applied to five additional test chemicals, and 15 molecular features were selected as either reported metabolites, predicted metabolites, or potential metabolites without a structural assignment. This study demonstrates that in some–but not all–cases, suspect screening analysis methods provide a means to rapidly identify and characterize metabolites of xenobiotic chemicals.

show abstract

Section: Discussionmentioning

confidence: 99%

Identifying xenobiotic metabolites with in silico prediction tools and LCMS suspect screening analysis

Boyce

Favela²,

Bonzo³

et al. 2023

Front. Toxicol.

View full text Add to dashboard Cite

show abstract

“…A decisive proof of the real enzymatic stability can only derive from in vivo studies that also give accounts of variations of the lifetime due to modifications of the molecular mass or the hydrophobicity, asit happens with PEGylation. However, it is worthy of note that new in silico tools for converting the results of in vitro toxicity tests into reliable predictions of in vivo behaviour are rapidly growing [ 118 ], although their full application on a large scale is currently limited by the incomplete knowledge of all the metabolic mechanisms involved in defining the toxicity of a drug.…”

Section: Enzymatic Stability and Methods For Its Determinationmentioning

confidence: 99%

Lights and Shadows on the Therapeutic Use of Antimicrobial Peptides

Bellotti

Remelli

2022

Molecules

View full text Add to dashboard Cite

The emergence of antimicrobial-resistant infections is still a major concern for public health worldwide. The number of pathogenic microorganisms capable of resisting common therapeutic treatments are constantly increasing, highlighting the need of innovative and more effective drugs. This phenomenon is strictly connected to the rapid metabolism of microorganisms: due to the huge number of mutations that can occur in a relatively short time, a colony can “adapt” to the pharmacological treatment with the evolution of new resistant species. However, the shortage of available antimicrobial drugs in clinical use is also caused by the high costs involved in developing and marketing new drugs without an adequate guarantee of an economic return; therefore, the pharmaceutical companies have reduced their investments in this area. The use of antimicrobial peptides (AMPs) represents a promising strategy for the design of new therapeutic agents. AMPs act as immune defense mediators of the host organism and show a poor ability to induce antimicrobial resistance, coupled with other advantages such as a broad spectrum of activity, not excessive synthetic costs and low toxicity of both the peptide itself and its own metabolites. It is also important to underline that many antimicrobial peptides, due to their inclination to attack cell membranes, have additional biological activities, such as, for example, as anti-cancer drugs. Unfortunately, they usually undergo rapid degradation by proteolytic enzymes and are characterized by poor bioavailability, preventing their extensive clinical use and landing on the pharmaceutical market. This review is focused on the strength and weak points of antimicrobial peptides as therapeutic agents. We give an overview on the AMPs already employed in clinical practice, which are examples of successful strategies aimed at overcoming the main drawbacks of peptide-based drugs. The review deepens the most promising strategies to design modified antimicrobial peptides with higher proteolytic stability with the purpose of giving a comprehensive summary of the commonly employed approaches to evaluate and optimize the peptide potentialities.

show abstract

“…In addition to high‐throughput platforms, advances such as three‐dimensional (3D) culturing and organ‐on‐chip are complementing traditional in vitro models (Akarapipad et al, 2021; Yang et al, 2021). Immortalized and primary hepatocytes from a variety of species grown as 3D spheroids have metabolic and gene expression profiles more similar to intact livers than traditional 2D monolayer cultures (Hartung, 2018; Moreau et al, 2022). While current in vitro testing approaches are useful for screening and qualitative characterization of mechanisms, additional progress in in vitro to in vivo extrapolations can strengthen quantitative risk characterization (Lammel et al, 2019; Ramaiahgari et al, 2017; Sharin et al, 2020; Takahashi et al, 2015).…”

Section: Overview Of Select Nonstandard Endpointsmentioning

confidence: 99%

Wildlife ecological risk assessment in the 21st century: Promising technologies to assess toxicological effects

Rattner

Bean

Beasley

et al. 2023

Integr Envir Assess & Manag

View full text Add to dashboard Cite

Despite advances in toxicity testing and the development of new approach methodologies (NAMs) for hazard assessment, the ecological risk assessment (ERA) framework for terrestrial wildlife (i.e., air‐breathing amphibians, reptiles, birds, and mammals) has remained unchanged for decades. While survival, growth, and reproductive endpoints derived from whole‐animal toxicity tests are central to hazard assessment, nonstandard measures of biological effects at multiple levels of biological organization (e.g., molecular, cellular, tissue, organ, organism, population, community, ecosystem) have the potential to enhance the relevance of prospective and retrospective wildlife ERAs. Other factors (e.g., indirect effects of contaminants on food supplies and infectious disease processes) are influenced by toxicants at individual, population, and community levels, and need to be factored into chemically based risk assessments to enhance the “eco” component of ERAs. Regulatory and logistical challenges often relegate such nonstandard endpoints and indirect effects to postregistration evaluations of pesticides and industrial chemicals and contaminated site evaluations. While NAMs are being developed, to date, their applications in ERAs focused on wildlife have been limited. No single magic tool or model will address all uncertainties in hazard assessment. Modernizing wildlife ERAs will likely entail combinations of laboratory‐ and field‐derived data at multiple levels of biological organization, knowledge collection solutions (e.g., systematic review, adverse outcome pathway frameworks), and inferential methods that facilitate integrations and risk estimations focused on species, populations, interspecific extrapolations, and ecosystem services modeling, with less dependence on whole‐animal data and simple hazard ratios. Integr Environ Assess Manag 2023;00:1–24. © 2023 His Majesty the King in Right of Canada and The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Reproduced with the permission of the Minister of Environment and Climate Change Canada. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

show abstract

Considerations for Improving Metabolism Predictions for In Vitro to In Vivo Extrapolation

Cited by 14 publications

References 60 publications

Identifying xenobiotic metabolites with in silico prediction tools and LCMS suspect screening analysis

Identifying xenobiotic metabolites with in silico prediction tools and LCMS suspect screening analysis

Lights and Shadows on the Therapeutic Use of Antimicrobial Peptides

Wildlife ecological risk assessment in the 21st century: Promising technologies to assess toxicological effects

Contact Info

Product

Resources

About