Simultaneous quantification of mirabegron and vibegron in human plasma by HPLC-MS/MS and its application in the clinical determination in patients with tumors associated with overactive bladder.

Mirabegron and vibegron, both newly identified beta-3 adrenergic agonists, have significantly improved the quality of life for patients suffering from overactive bladder. In order to comprehensively assess the plasma exposure levels of these agents, the development of a rapid and highly sensitive bioanalytical method becomes imperative. The primary objective of this study was to establish a robust high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for the concurrent quantification of mirabegron and vibegron in human plasma. The analytes were extracted from a 100 µL plasma sample through protein precipitation, employing 300 µL of methanol. Subsequently, samples underwent separation and quantification using a Waters XBridge C18 column (2.1 × 100 mm, 3.5 µm), with a mobile phase consisting of 0.1% formic acid in water and 0.1% formic acid in acetonitrile. The mass analysis was conducted using positive electrospray ionization (ESI+) operated in a multiple reaction monitoring (MRM) mode. The proposed method was meticulously validated in accordance with the guidelines set forth by the U.S. Food and Drug Administration (FDA) for bioanalytical method validation. The regression equations demonstrated exceptional linearity for both mirabegron (r² ≥ 0.994) and vibegron (r² ≥ 0.996) across the concentration range of 0.5 - 200 ng/mL. Furthermore, the assay exhibited accuracy (inter-day relative error ≤ 6.90%) and precision (inter-day coefficient of variation ≤ 8.88%). The average recoveries of the analytes were found to range from 81.94% to 102.02%, with mean matrix effects falling within the range of 89.77% to 110.58%. As a result, this method was deemed highly suitable for the precise determination of the concentrations of both mirabegron and vibegron in the context of therapeutic drug monitoring and bioequivalence studies.

K2S2O8-mediated direct C-H heteroarylation/hydroxylation of indolin-2-ones with quinoxalin-2(1H)-ones.

Herein, a K2S2O8-mediated direct heteroarylation and hydroxylation reaction between quinoxalin-2(1H)-ones with a C(sp2)-H bond and indolin-2-ones with a C(sp3)-H bond via an oxidative cross-coupling reaction has been reported. We have successfully established a feasible and concise reaction system that represents the first example of free-radical-promoted heteroarylation and hydroxylation reaction on the C-3 position of oxindole. A series of 3-substituted 3-hydroxyoxindoles are obtained in 0-83% yield using this methodology.

Role of sodium taurocholate cotransporting polypeptide (NTCP) in HBV-induced hepatitis: Opportunities for developing novel therapeutics.

Hepatitis B is an infectious disease caused by the HBV virus. It presents a significant challenge for treatment due to its chronic nature and the potential for developing severe complications, including hepatocirrhosis and hepatocellular carcinoma. These complications not only cause physical and psychological distress to patients but also impose substantial economic and social burdens on both individuals and society as a whole. The internalization of HBV relies on endocytosis and necessitates the involvement of various proteins, including heparin sulfate proteoglycans, epidermal growth factor receptors, and NTCP. Among these proteins, NTCP is pivotal in HBV internalization and is primarily located in the liver's basement membrane. As a transporter of bile acids, NTCP also serves as a receptor facilitating HBV entry into cells. Numerous molecules have been identified to thwart HBV infection by stifling NTCP activity, although only a handful exhibit low IC50 values. In this systematic review, our primary focus dwells on the structure and regulation of NTCP, as well as the mechanism involved in HBV internalization. We underscore recent drug breakthroughs that specifically target NTCP to combat HBV infection. By shedding light on these advances, this review contributes novel insights into developing effective anti-HBV medications.

Simultaneous quantification of donafenib, sorafenib, and their N-oxide metabolites in rat plasma using a HPLC-MS/MS method.

Donafenib and sorafenib are small molecule chemotherapy drugs for the management of hepatocellular carcinoma, with donafenib being a deuterated derivative of sorafenib. To date, a high liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method that quantify donafenib, sorafenib, and their main metabolites has not yet been developed. The objective of this study was to establish a HPLC-MS/MS method for the simultaneous detection of donafenib, donafenib-N-oxide, sorafenib, and sorafenib-N-oxide and for the pharmacokinetic studies in rat. The extraction of all analytes was achieved by simple protein precipitation utilizing acetonitrile. The Waters XBridge C18 column (2.1 × 100 mm, 3.5 µm) was selected, and the analytes could be efficiently separated and quantitated during a 2.8 min gradient elution procedure. The method was linear within the predefined quantification ranges and provided acceptable precision (%CV < 9.4%), reproducible extraction recovery (99.4%-111.5%), and low matrix effect (88.1%-98.6%). The hemolysis effect did not interfere with the quantification of all analytes, and similar results were obtained by changing the anticoagulant K2-EDTA to heparin or sodium citrate. Plasma pharmacokinetics revealed that the values of t1/2, Cmax, and AUC0-t of donafenib were 1.4-, 6.2-, and 3.1-fold higher than those of sorafenib, respectively. In conclusion, the proposed bioassay was successfully applied to pharmacokinetic studies in rat after administration of donafenib and sorafenib. Our work not only improves the bioanalytical method for determining the plasma concentrations of donafenib, sorafenib, and their N-oxide metabolites, but also provides a scientific reference for clinical pharmacokinetic studies.

Effects of the CYP3A inhibitors, voriconazole, itraconazole, and fluconazole on the pharmacokinetics of osimertinib in rats.

Background: Osimertinib, as third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), is the first-line treatment approved to treat advanced T790M mutation-positive tumors. Triazole antifungals are therapeutic drugs for cancer patients to reduce the risk of opportunistic fungal infections. Our objective was to investigate whether three triazole antifungals (voriconazole, itraconazole, and fluconazole) could change the pharmacokinetics of osimertinib in rats. Methods: The adult male Sprague-Dawley rats were randomly divided into four groups (n = 6): control (0.3% CMC-Na), and voriconazole (20 mg/kg), itraconazole (20 mg/kg), or fluconazole (20 mg/kg) combined with osimertinib (10 mg/kg) group. Tail vein blood samples were collected into heparin tubes at various time points within 0-48 h after osimertinib administration. Osimrtinib's plasma concentration was detected using HPLC-MS/MS system equipped with a Waters XBridge C18 column, with the mobile phase consisting of acetonitrile and 0.2% formic acid water at a flow rate of 0.5 mL/min. Results: Co-administration with voriconazole or fluconazole increased the Cmax of osimertinib by 58.04% and 53.45%, respectively; the AUC0-t increased by 62.56% and 100.98%, respectively. However, when co-administered with itraconazole, the Cmax and AUC0-t of osimertinib only increased by 13.91% and 34.80%, respectively. Conclusions: Our results revealed that the pharmacokinetics of osimertinib were significantly changed by voriconazole and fluconazole in rats, whereas it was slightly affected by itraconazole. This work will contribute to a more comprehensive understanding of the pharmacokinetic properties of osimertinib when co-administered with triazole antifungals.

Role of ferroptosis in fibrosis diseases.

Ferroptosis is a pervasive non-apoptotic mode of cell death that is different from autophagy or necrosis. It is mainly caused by an imbalance between the production and degradation of lipid reactive oxygen species in cells. Several metabolic pathways and biochemical processes, such as amino acid and lipid metabolism, iron handling, and mitochondrial respiration, affect and regulate cell sensitivity to peroxidation and ferroptosis. Organ fibrosis, a pathological manifestation of several etiological conditions, leads to chronic tissue injury and is characterized by excessive deposition of extracellular matrix components. Excessive tissue fibrosis can have diverse pathophysiological effects on several organ systems, eventually causing organ dysfunction and failure. The current manuscript provides a review that illustrates the link between ferroptosis and organ fibrosis and to better understand the underlying mechanisms. It provides novel potential therapeutic approaches and targets for fibrosis diseases.

Single-cell sequencing analysis fibrosis provides insights into the pathobiological cell types and cytokines of radiation-induced pulmonary fibrosis.

BACKGROUND: Radiotherapy is an essential treatment for chest cancer. Radiation-induced pulmonary fibrosis (RIPF) is an almost irreversible interstitial lung disease; however, its pathogenesis remains unclear. METHODS: We analyzed specific changes in cell populations and potential markers by using single-cell sequencing datasets from the Sequence Read Archive database, PERFORMED from control (0 Gy) and thoracic irradiated (20 Gy) mouse lungs at day 150 post-radiation. We performed IHC and ELISA on lung tissue and cells to validate the potential marker cytokines identified by the analysis on rat thoracic irradiated molds (30 Gy). RESULTS: Single-cell sequencing analysis showed changes in abundance across cell types and at the single-cell level, with B and T cells showing the most significant changes in abundance. And four cytokines, CCL5, ICAM1, PF4, and TNF, were significantly upregulated in lung tissues of RIPF rats and cell supernatants after ionizing radiation. CONCLUSION: Cytokines CCL5, ICAM1, PF4, and TNF may play essential roles in radiation pulmonary fibrosis. They are potential targets for the treatment of radiation pulmonary fibrosis.

Development and validation of a novel LC-MS/MS method for simultaneous quantitative determination of tyrosine kinase inhibitors in human plasma.

The objective of this study was to develop and validate a simple, rapid, and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of three tyrosine kinase inhibitors (ceritinib, osimertinib, and crizotinib) in human plasma using a single-step protein precipitation extraction. Chromatographic separation was achieved using a Waters X Bridge C18 (2.1 mm × 100 mm, 3.5 µm) and gradient elution with 0.2 % formic acid in water and acetonitrile. The total run time was 4.0 min, and the injection volume was 5 µL. The analytes were detected in the multiple reaction monitoring mode using electrospray ionization with positive ion mode. The m/z transitions of ceritinib, osimertinib, crizotinib and nilotinib were 558.0 â†’ 433.2, 500.0 â†’ 72.1, 450.0 â†’ 259.3, and 530.0 â†’ 289.1, respectively. The method was linear in the range of 2-500 ng/mL with lower limit of quantification of 2 ng/mL. Based on the guidelines on bioanalytical methods by the FDA, the validation studies demonstrated that the three analytes were both precise and accurate at four concentration levels, and the coefficient of variation was < 10.59 % and accuracy was > 88.26 %. We present a simple, rapid, and sensitive method for the simultaneous quantification of ceritinib, osimertinib, and crizotinib in human plasma by LC-MS/MS, which could be used in routine therapeutic drug monitoring.

Overview of PROTACs Targeting the Estrogen Receptor: Achievements for Biological and Drug Discovery.

Estrogen receptors (ERs) are steroid hormone receptors, which belong to a large nuclear receptor family. Endocrine diseases correlate strongly with dysregulated ER signaling. Traditional therapies continue to rely on small molecule inhibitors, including aromatase inhibitors (AIs) and selective estrogen receptor modulators (SERMs), all of which permit acquired resistance to endocrine therapy. Proteolytic targeting chimeras (PROTACs) offer unprecedented potential for solving acquired endocrine resistance. ARV-471, an ER-targeting PROTAC developed by Arvinas, was designated as an Investigational New Drug by the US FDA in 2019, and a phase I trial in patients suffering from locally advanced or metastatic ER-positive/HER2- negative breast cancer was initiated. In this review, we will focus on progress in developing ER-targeting PROTACs from publications and patents aimed at the treatment of endocrine diseases.