RESUMEN

[2,3-diamino-N-(4-(benzo[d]thiazol-2-yl)phenyl)propanamide], named as ETN101, is a novel therapeutic agent for hepatocellular carcinoma. In vitro studies examined ETN101 metabolites in human, mouse, rat, dog, and monkey hepatocytes and identified the drug-metabolizing enzymes involved using cDNA-expressed human recombinant cytochrome P450s (CYPs), carboxylesterases (CESs), N-acetyltransferase (NAT) 1, and human liver cytosol. ETN101 showed similar metabolic stability across hepatocytes from five species, with particularly comparable stability in humans, rats, and monkeys. Its half-life was 75.0 min in humans, 68.9 in rats, 73.1 in monkeys, 120.4 in mice, and 112.7 in dogs. Thirty-four ETN101 metabolites, including the major metabolite M1, were identified using liquid chromatography-high-resolution mass spectrometry. ETN101 was primarily metabolized to M1 and CYP1A2 is exclusively responsible for M1 metabolism. Both NAT1 and NAT2 were responsible for the N-acetylation of M1 to M2. ETN101 remained stable in human CESs. In conclusion, this study provides comprehensive insights into the metabolic characteristics of ETN101, valuable for its toxicological and clinical development.

RESUMEN

Feature-based molecular networking (FBMN) is a powerful analytical tool for mass spectrometry (MS)-based untargeted metabolomics data analysis. FBMN plays an important role in drug metabolism studies, enabling the visualization of complex metabolomics data to achieve metabolite characterization. In this study, we propose a strategy for the characterization of glutathione (GSH) adducts formed via in vitro metabolic activation using FBMN assisted by multivariate analysis (MVA). Acetaminophen was used as a model substrate for method development, and the practical potential of the method was investigated by its application to 2-aminophenol (2-AP) and 2,4-dinitrochlorobenzene (DNCB). Two 2-AP GSH adducts and one DNCB GSH adduct were successfully characterized by forming networks with GSH even though the mass spectral information obtained for the parent compound was deficient. False positives were effectively filtered out by the variable influence on projection cutoff criteria obtained from orthogonal partial least-squares-discriminant analysis. The GSH adducts formed by enzymatic or nonenzymatic reactions were intuitively distinguished by the pie chart of FBMN results. In summary, our approach effectively characterizes GSH adducts, which serve as compelling evidence of bioactivation. It can be widely utilized to enhance risk assessment in the context of drug metabolism.

Asunto(s)

RESUMEN

Fenbendazole (FBZ), a benzimidazole carbamate anthelmintic, has attracted attention for its antitumor activity. This study examined the metabolic characteristics of FBZ in humans compared with those in dogs. The phase I metabolites were identified in liver microsomal incubates using liquid chromatography-mass spectrometry (MS)-based untargeted metabolomics approaches. Seven metabolites of FBZ were identified by principal component analysis and orthogonal partial least square-discriminant analysis based on the global ion variables of the FBZ incubation groups. The chemical structure of the FBZ metabolites was suggested by examining the MS/MS spectrum and isotope distribution pattern. Cytochrome P450 (CYP) 1A1, CYP2D6, and CYP2J2 were the major isozymes responsible for the FBZ metabolism. No differences in the types of metabolites produced by the two species were noted. Multivariate analysis of human and dog incubation groups showed that five metabolites were relatively abundant in humans and the other two were not. In summary, the phase I metabolic profile of FBZ and the comparative metabolism between humans and dogs were examined using an untargeted metabolomics approach. This study suggests a successful investigation of FBZ metabolism in humans for conducting safety assessments regarding drug repositioning.

Asunto(s)

RESUMEN

Pancreatic islet transplantation holds great potential as a curative therapy for treating type 1 diabetes. However, the need for lifelong systemic immunosuppression with inevitable side effects is an obstacle to clinical success. Here we devised a strategy for the site-specific delivery of an immunosuppressant (tacrolimus) using layer-by-layer assembly of polymeric particles and collagen on the islet surface. This approach aims to provide a continuous and sustained supply of tacrolimus in the vicinity of transplanted cells while avoiding systemic drug exposure. The dose and release rate of tacrolimus can be tunable to achieve therapeutic windows by varying layer-by-layer construction and chemistry of polymers. Transplanting 400 IEQ of pancreatic islets coated with particles containing ∼3 µg of TAC per recipient provided controlled drug release and rectified diabetes for up to 5 months in a xenogeneic rodent model of type 1 diabetes. We anticipate that the findings of this study will be found useful by those developing local immunomodulation strategies aimed at improving the outcomes and safety of cell therapies for curing type 1 diabetes.

Asunto(s)

RESUMEN

Ethanol intake can alter pharmacokinetics by increasing the solubility or enhancing the absorption of concomitant drugs. Here, a selective, sensitive and reproducible high-performance liquid chromatography-tandem mass spectrometry method for the quantitative analysis of nicardipine in rat plasma was developed using simple protein precipitation. The calibration curve was linear over a concentration range of 1-2,000 ng/ml (r2 > 0.998). Accuracy ranged from 93.4 to 112.2% and precision was within 12.1% from three independent analytical batches. Stable conditions for the quantification of nicardipine in rat plasma were established in various conditions, including sample storage and handling. The matrix effect was negligible, and recovery was consistent at three different levels of quality control sample. The method was applied to assessment for the effect of ethanol on the pharmacokinetics of nicardipine in rats. The oral bioavailability of nicardipine was increased from 5.4 to 9.4% in Sprague-Dawley rats by concomitant oral administration of ethanol whereas the half-life was not altered. The findings indicated that concomitant ethanol intake can increase systemic drug exposure by increasing gastrointestinal absorption, especially poorly soluble drugs. This study provides an insight for further investigation of the alteration of the pharmacological effect of poorly soluble drugs owing to ethanol intake.

Asunto(s)