Untargeted screening of phase I metabolism of combretastatin A4 by multi-tool analysis

Rapid investigating of phase I metabolites of SR9009 in vitro horse liver microsomes via feature-based molecular networking approach: Potential applications in doping control

SR9009, a peroxisome proliferator-activated receptor δ (PPARδ) agonist, is known for its potential benefits in energy homeostasis. It failed to receive the United States Food and Drug Administration (USFDA) approval and its illegal distribution has raised concerns. As a result, it has been classified as a prohibited substance by the World Anti-Doping Agency and the International Federation of Horseracing Authorities (IFHA). This study emphasizes the application of the in-silico molecular networking technology to analyze phase I drug metabolites in horses, distinguishing it from conventional methodologies in forensic science. Feature-based molecular networking (FBMN) analysis identified 15 metabolites, with novel major N-dealkylated metabolite (-C8H7NO4S), indicative of diverse metabolic modifications in horse liver microsomes incubation assay. Additionally, a proposed metabolic pathway of SR9009 in the in vitro assay was outlined, including the previously known dehydroxylated metabolite. Finally, the metabolic pathways included in this study were as follows: hydroxylation, dehydrogenation, N-dealkylation dihydroxylation, and combinations. Molecular networking provided insights into MS spectra connectivity, facilitating rapid interpretation and accurate detection of previously undiscovered metabolites. In conclusion, this study contributes to the understanding of SR9009 metabolism in horses and underscores the importance of advanced analytical techniques, such as molecular networking, in enhancing the accuracy and efficiency of metabolite analysis for forensic and doping control purposes.

Recent advances in the use of SPME for drug analysis in clinical, toxicological, and forensic medicine studies

Solid-phase microextraction (SPME) has gained attention as a simple, fast, and non-exhaustive extraction technique, as its unique features enable its use for the extraction of many classes of drugs from biological matrices. This sample-preparation approach consolidates sampling and sample preparation into a single step, in addition to providing analyte preconcentration and sample clean-up. These features have helped SPME become an integral part of several analytical protocols for monitoring drug concentrations in human matrices in clinical, toxicological, and forensic medicine studies. Over the years, researchers have continued to develop the SPME technique, resulting in the introduction of novel sorbents and geometries, which have resulted in improved extraction efficiencies. This review summarizes developments and applications of SPME published between 2016 and 2022, specifically in relation to the analysis of central nervous system drugs, drugs used to treat cardiovascular disorders and bacterial infections, and drugs used in immunosuppressive and anticancer therapies.

Pharmacokinetic Profile Evaluation of Novel Combretastatin Derivative, LASSBio-1920, as a Promising Colorectal Anticancer Agent

LASSBio-1920 was synthesized due to the poor solubility of its natural precursor, combretastatin A4 (CA4). The cytotoxic potential of the compound against human colorectal cancer cells (HCT-116) and non-small cell lung cancer cells (PC-9) was evaluated, yielding IC₅₀ values of 0.06 and 0.07 μM, respectively. Its mechanism of action was analyzed by microscopy and flow cytometry, where LASSBio-1920 was found to induce apoptosis. Molecular docking simulations and the enzymatic inhibition study with wild-type (wt) EGFR indicated enzyme-substrate interactions similar to other tyrosine kinase inhibitors. We suggest that LASSBio-1920 is metabolized by O-demethylation and NADPH generation. LASSBio-1920 demonstrated excellent absorption in the gastrointestinal tract and high central nervous system (CNS) permeability. The pharmacokinetic parameters obtained by predictions indicated that the compound presents zero-order kinetics and, in a human module simulation, accumulates in the liver, heart, gut, and spleen. The pharmacokinetic parameters obtained will serve as the basis to initiate in vivo studies regarding LASSBio-1920's antitumor potential.

Combination of electrochemical unit and ESI-MS in fragmentation of flavonoids

INTRODUCTION

Predictive approaches on the activity of natural compounds based on the fragmentation by instrumental techniques are important for consideration of such molecules as drug candidates and defining new structures with promising properties. Since flavonoids are well-known antioxidants, their redox properties can be related to their pharmacological activity.

OBJECTIVES

In this work, the potential of electrochemical unit coupled to electrospray ionisation mass spectrometry (ESI-MS) was assessed for fragmentation activity relationships studies of selected flavonoids.

METHODOLOGY

Methodology of this research included electrochemical conversion of standards of flavonoids at different pH values and their further analysis with the use of ESI-MS. In addition, signals obtained from the blank samples were also identified and used for interpretation due to electrochemical nature of the ESI source. Half maximal inhibitory concentration (IC₅₀ ) values of flavonoids for 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant activity assays were analysed for possible correlation with the structures of flavonoids and products of electrochemical conversion.

RESULTS

Fragmentation activity relationships were suggested using the proposed approach and for some of the flavonoids it was not specific enough to determine the input of a particular structural feature to the activity, but for others they were in agreement with those found in the literature. Obtained results showed potential of the proposed approach for application in plant sciences as a fast pre-screening tool for newly isolated bioactive compounds.