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Chemico-biological Interactions Sep 2023Metaxalone (MTX) is a central nervous system (CNS) depressant used for the treatment of acute skeletal muscle pain. Several cases of fatal overdose deaths in the...
Metaxalone (MTX) is a central nervous system (CNS) depressant used for the treatment of acute skeletal muscle pain. Several cases of fatal overdose deaths in the clinical use of MTX, along with the presence of ischemic hepatitis in deceased patients, have been documented. The present study aimed to investigate the metabolic activation of MTX and to define the possible correlation between the metabolic activation and cytotoxicity of MTX. An oxidative metabolite (M1) and a GSH conjugate (M2) were observed in S9 fraction incubations as well as in rat primary hepatocyte culture after exposure to MTX. M1 and M2 were also observed in bile of MTX-treated rats. CYP2A6 was found to dominate the oxidation of MTX. Both methoxsalen (MTS, a CYP2A6 inhibitor) and 2,6-dichloro-4-nitrophenol (DCNP, a sulfotransferase inhibitor) dramatically decreased the formation of M2. Pre-treatment of primary hepatocytes with DCNP or MTS significantly decreased the susceptibility to the cytotoxicity of MTX.
Topics: Rats; Animals; Activation, Metabolic; Sulfotransferases; Cytochrome P-450 Enzyme System; Microsomes, Liver; Glutathione
PubMed: 37442290
DOI: 10.1016/j.cbi.2023.110628 -
Vox Sanguinis Sep 2023Extracorporeal photopheresis (ECP) is a widespread cellular therapy for graft-versus-host disease, autoimmune diseases and Sézary disease. One of the main effects of...
BACKGROUND AND OBJECTIVES
Extracorporeal photopheresis (ECP) is a widespread cellular therapy for graft-versus-host disease, autoimmune diseases and Sézary disease. One of the main effects of ECP is the apoptosis of leukocytes, but the therapeutic mechanisms are not completely known. The aim of this study was to investigate the effects on red blood cells, platelets and the induction of reactive oxygen species.
MATERIALS AND METHODS
We used human cells from healthy blood donors to simulate in vitro the composition in an apheresis bag. Cells were treated with 8-methoxypsoralen (8-MOP) and UVA. Red blood cell stability, platelet activity and induction of reactive oxygen species were analysed.
RESULTS
After 8-MOP and UVA treatment, the red blood cells showed high cell integrity with low levels of eryptosis and no increase of free haemoglobin or red blood cell distribution width (RDW). Red blood cell immune-associated antigens CD59 and CD147 were hardly affected by the treatment. Platelet glycoproteins CD41, CD62P and CD63 indicated strong platelet activation after 8-MOP and UVA treatment. Reactive oxygen species were slightly but not significantly induced by the treatment.
CONCLUSION
The effect of the ECP therapy is probably not exclusively mediated by leukocytes. Platelet activation is another striking effect caused by the treatment of the apheresis product with 8-MOP/UVA. However, since we could hardly identify any evidence for eryptosis or haemolysis, it is unlikely that red blood cell eryptosis is part of the therapeutic mechanism. Further research on this topic seems to be promising.
Topics: Humans; Methoxsalen; Reactive Oxygen Species; Photopheresis; Blood Platelets; Erythrocytes
PubMed: 37401421
DOI: 10.1111/vox.13489 -
BioRxiv : the Preprint Server For... Jun 2023Cigarette smoking remains the leading preventable cause of disease and death. Nicotine is the primary reinforcing ingredient in cigarettes sustaining addiction. Cotinine...
Cigarette smoking remains the leading preventable cause of disease and death. Nicotine is the primary reinforcing ingredient in cigarettes sustaining addiction. Cotinine is the major metabolite of nicotine that produces a myriad of neurobehavioral effects. Cotinine supported self-administration and rats with a history of intravenous self-administration of cotinine exhibited relapse-like drug-seeking behavior, suggesting cotinine may also be reinforcing. To date, a potential contribution of cotinine to nicotine reinforcement remains unknown. Nicotine metabolism is mainly catalyzed by hepatic CYP2B1 enzyme in the rat and methoxsalen is a potent CYP2B1 inhibitor. The study tested the hypothesis that methoxsalen inbibits nicotine metabolism and self-administration, and that cotinine replacement attenuates the inhibitory effects of methoxsalen. Acute methoxsalen decreased plasma cotinine levels and increased nicotine levels following subcutaneous nicotine injection. Repeated methoxsalen reduced the acquisition of nicotine self-administration, leading to fewer nicotine infusions, disruption of lever differentiation, smaller total nicotine intake, and lower plasma cotinine levels. On the other hand, methoxsalen did not alter nicotine self-administration during the maintenance phase despite great reduction of plasma cotinine levels. Cotinine replacement by mixing cotinine with nicotine for self-administration dose-dependently increased plasma cotinine levels, counteracted effects of methoxsalen, and enhanced the acquisition of self-administration. Neither basal nor nicotine-induced locomotor activity was altered by methoxsalen. These results indicate that methoxsalen depressed cotinine formation from nicotine and the acquisition of nicotine self-administration, and that replacement of plasma cotinine attenuated the inhibitory effects of methoxsalen, suggesting that cotinine may contribute to the development of nicotine reinforcement.
PubMed: 37333320
DOI: 10.1101/2023.06.04.543614 -
Biomedicine & Pharmacotherapy =... Jul 2023Thrombocytopenia is a common hematological disease caused by many factors. It usually complicates critical diseases and increases morbidity and mortality. The treatment...
BACKGROUND
Thrombocytopenia is a common hematological disease caused by many factors. It usually complicates critical diseases and increases morbidity and mortality. The treatment of thrombocytopenia remains a great challenge in clinical practice, however, its treatment options are limited. In this study, the active monomer xanthotoxin (XAT) was screened out to explore its medicinal value and provide novel therapeutic strategies for the clinical treatment of thrombocytopenia.
METHODS
The effects of XAT on megakaryocyte differentiation and maturation were detected by flow cytometry, Giemsa and phalloidin staining. RNA-seq identified differentially expressed genes and enriched pathways. The signaling pathway and transcription factors were verified through WB and immunofluorescence staining. Tg (cd41: eGFP) transgenic zebrafish and mice with thrombocytopenia were used to evaluate the biological activity of XAT on platelet formation and the related hematopoietic organ index in vivo.
RESULTS
XAT promoted the differentiation and maturation of Meg-01 cells in vitro. Meanwhile, XAT could stimulate platelet formation in transgenic zebrafish and recover platelet production and function in irradiation-induced thrombocytopenia mice. Further RNA-seq prediction and WB verification revealed that XAT activates the IL-1R1 target and MEK/ERK signaling pathway, and upregulates the expression of transcription factors related to the hematopoietic lineage to promote megakaryocyte differentiation and platelet formation.
CONCLUSION
XAT accelerates megakaryocyte differentiation and maturation to promote platelet production and recovery through triggering IL-1R1 and activating the MEK/ERK signaling pathway, providing a new pharmacotherapy strategy for thrombocytopenia.
Topics: Mice; Animals; Thrombopoiesis; Blood Platelets; Megakaryocytes; Methoxsalen; Zebrafish; Thrombocytopenia; Transcription Factors; Signal Transduction; Mitogen-Activated Protein Kinase Kinases
PubMed: 37156117
DOI: 10.1016/j.biopha.2023.114811 -
Archives of Biochemistry and Biophysics Jun 2023This study aimed to investigate the effect and mechanism of 8-methoxypsoralen (8-MOP) on acetaminophen (APAP)-induced hepatotoxicity in mice. The study found that 1 h...
This study aimed to investigate the effect and mechanism of 8-methoxypsoralen (8-MOP) on acetaminophen (APAP)-induced hepatotoxicity in mice. The study found that 1 h after intraperitoneal injection of 300 mg/kg APAP, treatment with 40 mg/kg, 80 mg/kg and 120 mg/kg 8-MOP could reduce serum transaminase level and histopathological liver necrosis area. Elevated mRNA expression of liver inflammatory mediators caused by excessive APAP was also reversed. 8-MOP significantly reduced APAP-induced hepatotoxicity dose-dependently, and the highest therapeutic dose of 8-MOP (120 mg/kg) had no harmful effects on the liver. Cocktail probe assay revealed that 8-MOP can inhibit Cyp2e1 enzymatic activities of mice, thereby reducing the production of acetaminophen-cysteine (APAP-CYS), a toxic metabolite of APAP. 8-MOP had no significant effect on the protein and gene expression of Cyp2e1. The three-dimensional structures of mouse Cyp2e1 were constructed by homologous modeling. Molecular docking showed that 8-MOP had a good binding effect on the enzyme activity site of Cyp2e1. In summary, 8-MOP dose-dependently attenuated APAP-induced hepatotoxicity by binding to Cyp2e1 and occupying the active center of the enzyme, thus competitively inhibiting the oxidative metabolism of APAP, and reducing the generation of toxic product APAP-CYS.
Topics: Animals; Mice; Acetaminophen; Chemical and Drug Induced Liver Injury; Cytochrome P-450 CYP2E1; Liver; Methoxsalen; Molecular Docking Simulation
PubMed: 37121295
DOI: 10.1016/j.abb.2023.109617 -
Pesticide Biochemistry and Physiology May 2023Phytochemicals are a class of potential pesticides for pest control. Our previous studies have demonstrated that the development of Spodoptera litura is suppressed by...
Phytochemicals are a class of potential pesticides for pest control. Our previous studies have demonstrated that the development of Spodoptera litura is suppressed by two phytochemicals, flavone and xanthotoxin. Generally, phytochemical is metabolized by insect detoxification enzyme systems. Nuclear receptor (NR) is the ligand-activated transcription factor that involved in the regulation of detoxification gene expressions. To explore how NR responds to phytochemical to mediate detoxification gene expression, in the present study, 19 NRs were firstly identified in S. litura genome. The transcriptional levels of most NRs were significantly induced in the midgut of S. litura larvae after exposure to flavone and xanthotoxin. RNAi-mediated knockdown of FTZF1, EcR, Dsf, and HR3 remarkably reduced the larval tolerance to flavone or xanthotoxin. In addition, many crucial detoxification genes were downregulated by dsNR administrations, which might be responsible for the high sensitivity of S. litura to phytochemicals. Molecular docking indicated that phytochemicals as the potential ligands had high affinity to bind to NRs. This study suggested that NR potentially regulated the transcriptional expression of detoxification genes in response to phytochemical stresses, which partially elucidated the mechanism of extensive host adaptation in S. litura and provided the theoretical evidences for the development of NR-targeted insecticides.
Topics: Animals; Spodoptera; Methoxsalen; Molecular Docking Simulation; Insecticides; Larva; Phytochemicals; Receptors, Cytoplasmic and Nuclear; Flavones
PubMed: 37105640
DOI: 10.1016/j.pestbp.2023.105417 -
Journal of Food Protection Jun 2023In this research, we evaluated the aphicidal effect of the ethanolic extract of stems and bark of Ficus petiolaris Kunth (Moraceae), in laboratory bioassays in an...
In this research, we evaluated the aphicidal effect of the ethanolic extract of stems and bark of Ficus petiolaris Kunth (Moraceae), in laboratory bioassays in an artificial diet against apterous adult females of Melanaphis sacchari Zehntner (Hemiptera: Aphididae). The extract was evaluated at different concentrations (500, 1,000, 1,500, 2,000, and 2,500 ppm), and the highest percentage of mortality (82%) was found at 2,500 ppm after 72 h. The positive control imidacloprid (Confial®) at 1% eliminated 100% of the aphids, and the negative control (artificial diet) only presented mortality of 4%. The chemical fractionation of the stem and bark extract of F. petiolaris yielded five fractions of FpR1-5, which were each evaluated at 250, 500, 750, and 1,000 ppm. FpR2 had the strongest aphicidal effect, with 89% mortality at 72 h at 1,000 ppm. The pure xanthotoxin compound extracted from this fraction was even more effective, with 91% aphid mortality after 72 h at 100 ppm. The lethal concentration (LC) of xanthotoxin was 58.7 ppm (72 h). Our results indicate that the extract of F. petiolaris showed toxic activity against this aphid, and its xanthotoxin compound showed strong aphicidal activity at low concentrations.
Topics: Animals; Female; Aphids; Ficus; Methoxsalen; Sorghum; Plant Extracts
PubMed: 37019182
DOI: 10.1016/j.jfp.2023.100084 -
Chemical Research in Toxicology Mar 2023Xanthotoxin (XTT) is a biologically active furanocoumarin widely present in foods and plants. The present study is designed to systematically investigate the enzymatic...
Xanthotoxin (XTT) is a biologically active furanocoumarin widely present in foods and plants. The present study is designed to systematically investigate the enzymatic interaction of XTT with CYP1A2, along with pharmacokinetic alteration of tacrine resulting from the co-administration of XTT. The results showed that XTT induced a time-, concentration-, and NADPH-dependent inhibition of CYP1A2, and the inhibition was irreversible. Co-incubation of glutathione (GSH) and catalase/superoxide dismutase was unable to prevent enzyme inactivation. Nevertheless, competitive inhibitor fluvoxamine exhibited a concentration-dependent protective effect against the XTT-induced CYP1A2 inactivation. A GSH trapping experiment provided strong evidence for the production of epoxide or/and γ-ketoenal intermediates resulting from the metabolic activation of XTT. Furthermore, pretreatment of rats with XTT was found to significantly increase the and area under the curve of plasma tacrine relative to those of tacrine administration alone.
Topics: Animals; Rats; Cytochrome P-450 CYP1A2; Drug Interactions; Fluvoxamine; Methoxsalen; Tacrine
PubMed: 36892569
DOI: 10.1021/acs.chemrestox.2c00360 -
Bioorganic & Medicinal Chemistry Letters Apr 2023Cytochrome P450 2A6 (CYP2A6) inhibitors are expected to be suitable as smoking cessation aids and for cancer prevention. Because the typical coumarin-based CYP2A6...
Cytochrome P450 2A6 (CYP2A6) inhibitors are expected to be suitable as smoking cessation aids and for cancer prevention. Because the typical coumarin-based CYP2A6 inhibitor methoxsalen also inhibits CYP3A4, unintended drug-drug interactions are still a concern. Therefore, the development of selective CYP2A6 inhibitors is desirable. In this study, we synthesized coumarin-based molecules, determined the IC values for CYP2A6 inhibition, verified the possibility of mechanism-based inhibition, and compared the selectivity for CYP2A6 versus CYP3A4. The results demonstrated that we developed CYP2A6 inhibitors that were more potent and selective than methoxsalen.
Topics: Aryl Hydrocarbon Hydroxylases; Cytochrome P-450 Enzyme Inhibitors; Cytochrome P-450 CYP3A; Methoxsalen; Coumarins; Cytochrome P-450 CYP2A6; Microsomes, Liver
PubMed: 36889653
DOI: 10.1016/j.bmcl.2023.129206 -
Evidence-based Complementary and... 2022Keyin pill (KP), a patented medicine in China, is used to treat psoriasis. However, KP has been reported to have liver toxicity, but its toxic substance basis and...
BACKGROUND
Keyin pill (KP), a patented medicine in China, is used to treat psoriasis. However, KP has been reported to have liver toxicity, but its toxic substance basis and underlying mechanisms remain unclear. Therefore, this study aimed to explore the pharmacological mechanisms and components of KP-induced liver injury through animal experiments, UPLC-QTOF/MS combined with network pharmacology.
METHODS
Firstly, based on the immune stress mouse model, liver function parameters and hematoxylin-eosin (H&E) staining were detected to investigate KP-induced liver injury. The UPLC-QTOF/MS method was used to identify the components of KP. CTD database and literature mining were further applied to screen nonliver protective components. Subsequently, the nonliver protective components and their corresponding targets and targets of hepatotoxicity were analyzed by the method of network pharmacology. Finally, key targets from networked pharmacology were examined by the enzyme-linked immunosorbent assay (ELISA) and molecular docking.
RESULTS
Our results indicated that KP had hepatotoxicity in male Kunming mice, which could favor hepatocyte necrosis and infiltration of inflammatory cells. A total of 70 nonliver protective compounds were identified and screened. The results of network pharmacology illustrated that methoxsalen, obacunone, limonin, and dictamnine might be the main compounds that caused liver damage. The potential hepatotoxicity mechanisms of KP might be through the IL17 and apoptosis pathways to regulate IL6, TNF, CASP3, and CASP8 targets, thereby causing inflammation, excessive release of factors, and hepatocyte necrosis. The results of the ELISA experiments indicated that KP could increase the release of IL6 and TNF inflammatory factors in liver tissues. Molecular docking suggested that methoxsalen, obacunone, limonin, and dictamnine had moderate binding ability with CASP3 and CASP8.
CONCLUSION
In this study, the material basis and potential pharmacological mechanisms of KP-induced liver injury were preliminarily explored. Our research provides the initial theoretical basis for reducing the toxicity of KP.
PubMed: 36518852
DOI: 10.1155/2022/9916949