Extracellular Vesicles as Surrogates for Drug Metabolism and Clearance: Promise vs. Reality

Integrated technologies for molecular profiling of genetic and modified biomarkers in extracellular vesicles

Extracellular vesicles (EVs) are nanoscale membrane vesicles actively released by cells into a variety of biofluids. EVs carry myriad molecular cargoes; these include classical genetic biomarkers inherited from the parent cells as well as EV modifications by other entities (e.g., small molecule drugs). Aided by these diverse cargoes, EVs enable long-distance intercellular communication and have been directly implicated in various disease pathologies. As such, EVs are being increasingly recognized as a source of valuable biomarkers for minimally-invasive disease diagnostics and prognostics. Despite the clinical potential, EV molecular profiling remains challenging, especially in clinical settings. Due to the nanoscale dimension of EVs as well as the abundance of contaminants in biofluids, conventional EV detection methods have limited resolution, require extensive sample processing and can lose rare biomarkers. To address these challenges, new micro- and nanotechnologies have been developed to discover EV biomarkers and empower clinical applications. In this review, we introduce EV biogenesis for different cargo incorporation, and discuss the use of various EV biomarkers for clinical applications. We also assess different chip-based integrated technologies developed to measure genetic and modified biomarkers in EVs. Finally, we highlight future opportunities in technology development to facilitate the clinical translation of various EV biomarkers.

Extracellular vesicles: A potential new way to assess cholestasis

Extracellular vesicles (EVs) are small, nonreplicating, lipid-encapsulated nanoparticles that carry protein and nucleic acid cargo derived from their tissue of origin. Due to their capacity to provide comparable insights to solid organ biopsy through a minimally invasive collection procedure, EVs provide an attractive biomarker source. This review will provide an insight, how EVs in circulation may provide a novel way to assess cholestasis and will address the possibility of getting a better understanding of the mechanisms of cholestasis of pregnancy through the use of serial hepatic-specific EVs as a window.

Extracellular vesicles as the next-generation modulators of pharmacokinetics and pharmacodynamics of medications and their potential as adjuvant therapeutics

BACKGROUND AND MAIN BODY

Pharmacokinetics (PK) and pharmacodynamics (PD) are central concepts to guide the dosage and administration of drug therapies and are essential to consider for both healthcare professionals and researchers in therapeutic planning and drug discovery. PK/PD properties of a drug significantly influence variability in response to treatment, including therapeutic failure or excessive medication-related harm. Furthermore, suboptimal PK properties constitute a significant barrier to further development for some candidate treatments in drug discovery. This article describes how extracellular vesicles (EVs) affect different aspects of PK and PD of medications and their potential to modulate PK and PD properties to address problematic PK/PD profiles of drugs. We reviewed EVs' intrinsic effects on cell behaviours and medication responses. We also described how surface and cargo modifications can enhance EV functionalities and enable them as adjuvants to optimise the PK/PD profile of conventional medications. Furthermore, we demonstrated that various bioengineering strategies can be used to modify the properties of EVs, hence enhancing their potential to modulate PK and PD profile of medications.

CONCLUSION

This review uncovers the critical role of EVs in PK and PD modulation and motivates further research and the development of assays to unfold EVs' full potential in solving PK and PD-related problems. However, while we have shown that EVs play a vital role in modulating PK and PD properties of medications, we postulated that it is essential to define the context of use when designing and utilising EVs in pharmaceutical and medical applications.

HIGHLIGHTS

Existing solutions for pharmacokinetics and pharmacodynamics modulation are limited. Extracellular vesicles can optimise pharmacokinetics as a drug delivery vehicle. Biogenesis and administration of extracellular vesicles can signal cell response. The pharmaceutical potential of extracellular vesicles can be enhanced by surface and cargo bioengineering. When using extracellular vesicles as modulators of pharmacokinetics and pharmacodynamics, the 'context of use' must be considered.

Therapeutic drug monitoring, liquid biopsies or pharmacogenomics for prediction of human drug metabolism and response

Pharmacokinetics plays a central role in understanding the significant interindividual differences that exist in drug metabolism and response. Effectively addressing these differences requires a multi-faceted approach that encompasses a variety of tools and methods. In this review, we examine three key strategies to achieve this goal, namely pharmacogenomics, therapeutic drug monitoring (TDM) and liquid biopsy-based monitoring of hepatic ADME gene expression and highlight their advantages and limitations. We note that larger cohort studies are needed to validate the utility of liquid biopsy-based assessment of hepatic ADME gene expression, which includes prediction of drug metabolism in the clinical setting. Modern mass spectrometers have improved traditional TDM methods, offering versatility and sensitivity. In addition, the identification of endogenous or dietary markers for CYP metabolic traits offers simpler and more cost-effective alternatives to determine the phenotype. We believe that future pharmacogenomic applications in clinical practice should prioritize the identification of missing heritable factors, using larger, well-characterized patient studies and controlling for confounding factors such as diet, concomitant medication and physical health. The intricate regulation of ADME gene expression implies that large-scale studies combining long-read next-generation sequencing (NGS) of complete genomes with phenotyping of patients taking different medications are essential to identify these missing heritabilities. The continuous integration of such data into AI-driven analytical systems could provide a comprehensive and useful framework. This could lead to the development of highly effective algorithms to improve genetics-based precision treatment by predicting drug metabolism and response, significantly improving clinical outcomes.