Simultaneous Determination of Urine Methotrexate, 7-Hydroxy Methotrexate, Deoxyaminopteroic Acid, and 7-Hydroxy Deoxyaminopteroic Acid by UHPLC-MS/MS in Patients Receiving High-dose Methotrexate Therapy

Surface saturation of drug-loaded hollow manganese dioxide nanoparticles with human serum albumin for treating rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory joint disease accompanied by energy depletion and accumulation of reactive oxygen species (ROS). Inorganic nanoparticles (NPs) offer great promise for the treatment of RA because they mostly have functions beyond being drug carriers. However, conventional nanomaterials become coated with a protein corona (PC) or lose their cargo prematurely in vivo, reducing their therapeutic efficacy. To avoid these problems, we loaded methotrexate (MTX) into hollow structured manganese dioxide nanoparticles (H-MnO2 NPs), then coated them with a 'pseudo-corona' of human serum albumin (HSA) at physiological concentrations to obtain HSA-MnO2@MTX NPs. Efficacy of MTX, MnO2@MTX, and HSA-MnO2@MTX NPs was compared in vitro and in vivo. Compared to MnO2@MTX, HSA-coated NPs were taken up better by lipopolysaccharide-activated RAW264.7 and were more effective at lowering levels of pro-inflammatory cytokines and preventing ROS accumulation. HSA-MnO2@MTX NPs were also more efficient at blocking the proliferation and migration of fibroblast-like synoviocytes from rats with collagen-induced arthritis. In this rat model, HSA-MnO2@MTX NPs showed better biodistribution than other treatments, specifically targeting the ankle joint. Furthermore, HSA-MnO2@MTX NPs reduced swelling in the paw, regulated pro-inflammatory cytokine production, and limited cartilage degradation and signs of inflammation. These results establish the therapeutic potential of HSA-MnO2@MTX NPs against RA.

Contribution of aldehyde oxidase to methotrexate-induced hepatotoxicity: in vitro and pharmacoepidemiological approaches

BACKGROUND

Methotrexate (MTX) is partially metabolized by aldehyde oxidase (AOX) in the liver and its clinical impact remains unclear. In this study, we aimed to demonstrate how AOX contributes to MTX-induced hepatotoxicity in vitro and clarify the relationship between concomitant AOX inhibitor use and MTX-associated liver injury development using the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS).

METHODS

We assessed intracellular MTX accumulation and cytotoxicity using HepG2 cells. We used the FAERS database to detect reporting odds ratio (ROR)-based MTX-related hepatotoxicity event signals.

RESULTS

AOX inhibition by AOX inhibitor raloxifene and siRNA increased the MTX accumulation in HepG2 cells and enhanced the MTX-induced cell viability reduction. In the FAERS analysis, the ROR for MTX-related hepatotoxicity increased with non-overlap of 95% confidence interval when co-administered with drugs with higher Imax, u (maximum unbound plasma concentration)/IC50 (half-maximal inhibitory concentration for inhibition of AOX) calculated based on reported pharmacokinetic data.

CONCLUSION

AOX inhibition contributed to MTX accumulation in the liver, resulting in increased hepatotoxicity. Our study raises concerns regarding MTX-related hepatotoxicity when co-administered with drugs that possibly inhibit AOX activity at clinical concentrations.

Leucovorin (folinic acid) rescue for high-dose methotrexate: A review

High-dose methotrexate (HDMTX) is active against various malignancies; it possesses serious toxicities and is associated with patient characteristics, dosage regimens, comedications, and physiological status. There are many strategies to overcome HDMTX-induced toxicities, such as hydration, alkalization, leucovorin rescue, and haemodialysis. Leucovorin rescue is a cornerstone for toxicity prevention in HDMTX treatment. However, the leucovorin dose adjustment and the existence of leucovorin overrescue are still controversial. At present, various methods for calculating leucovorin doses in different tumour types have been proposed, including empirical calculations based on MTX plasma concentration, the Bleyer nomogram, and other methods. Nonetheless, leucovorin rescue protocols differ greatly across tumour types and medical institutions. Further studies are needed to investigate the optimal dosage regimen for leucovorin rescue in various tumours using HDMTX.

Simple, low-cost and sensitive electrochemical sensing of antineoplastic drug amethopterin based on a nanocarbon black modified electrode

Various methods have been proposed currently to detect amethopterin (ATP, a widely used anticancer drug that is also called methotrexate); however, a simple and low-cost electrochemical method coupled with high sensitivity is scarce. In this study, by using low-cost and readily available nanocarbon black (NCB), which has excellent conductivity and stable dispersion in water as well as large surface area, as electrode materials to modify a glassy carbon electrode (GCE), a simple, inexpensive and highly-sensitive electrochemical sensor was constructed based on NCB/GCE. The electrochemical behaviors of ATP at both NCB/GCE and GCE were studied; the results show that the peak current of ATP at NCB/GCE is extremely higher than that at the bare GCE. For sensing ATP with high sensitivity, various control conditions including accumulation time, pH values of the phosphate buffer solution and NCB amount were optimized. The quantitative testing results show that NCB/GCE presents excellent sensing performances with a wide linearity range from 0.01 to 10.0 μM and low limit of detection (4.0 nM) towards ATP. Moreover, the investigation in the reproducibility and stability as well as selectivity of NCB/GCE demonstrated that the related results are also satisfactory. It is thus simple and effective method for ATP analysis and has important applications.

Comparison of LC-MS3 and LC-MRM strategy for quantification of methotrexate in human plasma and its application in therapeutic drug monitoring

A simple, highly selective and high throughput liquid chromatography tandem mass spectrometry cubed (LC/MS³) method was developed and validated for quantification of methotrexate in human plasma. The MS³ detection is a scanning mode of QTrap MS systems or ion trap MS systems. After simple protein precipitation with methanol, methotrexate and methotrexate-d₃ were separated on an Agilent Poroshell 120 SB-C18 column (4.6 × 50 mm, 2.7 µm) using isocratic elution with a mobile phase consisting of 60% 0.1% formic acid in water and 40% 0.1% formic acid in acetonitrile. The flow rate is 0.8 mL/min. MS³ detection in positive ion mode used the MRM³ transitions at m/z 455.2→308.2→175.1 for quantification of methotrexate and m/z 458.2→311.2→175.1 for quantification of methotrexate-d₃. The total run time was only 3 min for each sample. The LC/MS³ assay was linear in the concentration range 10-3000 ng/mL(R² ≥ 0.995) and the intra- and inter-day accuracies were< 3.72% and precisions were< 7.78% at all concentrations. The absolute recoveries (%) and matrix effect (%) for methotrexate in human plasma were between 92.6 and 114.3. The novelty of the presented methodology is the MS³ technique resulting in enhanced selectivity and sensitivity. The application of this LC-MS³ method was successfully completed on 46 human plasma samples and the quantitative results of identical human plasma samples were compared with another LC-MRM based method. Passing-Bablok regression coefficients demonstrated that there is no significant difference between the LC-MS³ method and LC-MRM method. Bland-Altman plots showed a concordant results, supporting the developed LC-MS³ method is a reliable and accurate assay for determination of methotrexate in human plasma. This work is also a proof of concept for using LC-MS³ technique to determination of chemicals in biological samples.

Methotrexate Polyglutamates Analysis by Chromatography Methods in Biological Matrices: A Review

Methotrexate (MTX) is used as an immunosuppressant and antineoplastic drug in clinical practice. MTX is a parent drug and converts to MTX polyglutamates (MTXPGs) to exhibit its biological activity. Clinical studies found that MTXPG levels were associated with MTX response and toxicities, especially at low doses. Due to huge variance of MTX response and toxicities between individuals, therapeutic drug monitoring is necessary for its use in individualized therapy. Various chromatography methods coupled with ultraviolet-visible detector, fluorescence detector and mass spectrometry have been reported for MTXPG analysis in various biological matrices. The aim of this paper is to review the chromatographic based methods for the measurement of total and/or individual MTXPGs. We searched Embase, Science Direct and PubMed databases using "methotrexate polyglutamate" and "chromatography" as search terms, and found 745 articles. Of those, 14 articles were extracted for this study. The key steps for method development (sample pretreatment, parameter optimization of liquid chromatography and mass spectrometry, selection of internal standard) and validation (lower limit of quantitation, accuracy, precision, recovery, matrix effect and stability) were analyzed and summarized, which might be helpful for researchers to develop their own methods.