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Cardiovascular Toxicology Aug 2022Cardiac troponin T (encoded by TNNT2) is involved in the contraction of cardiomyocytes during beating. The alternative splicing of TNNT2 results in four transcript...
Cardiac troponin T (encoded by TNNT2) is involved in the contraction of cardiomyocytes during beating. The alternative splicing of TNNT2 results in four transcript variants with differential Ca sensitivity. The splicing of TNNT2 involves phosphorylation of the splicing factor SRSF6 by DYRK1A. Altered TNNT2 splicing patterns have been identified in failing human hearts. There is a paucity of studies describing DYRK1A-SRSF6-TNNT2 interplays in human cardiomyocytes. Also, it is not known whether the sensitivity of cardiomyocytes to cardiotoxic anthracyclines is modified in the context of variable DYRK1A-TNNT2 expression. In this study, we investigated the impact of DYRK1A on the endogenous expression of TNNT2 splicing variants in iPSC-derived cardiomyocytes. We also examined whether DYRK1A expression modifies the sensitivity of cardiomyocytes to the cardiotoxic drug daunorubicin (DAU). DYRK1A over-expression increased the abundance of TNNT2 fetal variants by ~ 58% whereas the abundance of the adult cTnT3 variant decreased by ~ 27%. High DYRK1A expression increased the phosphorylation of SRSF6 by ~ 25-65%. DAU cytotoxicity was similar between cardiomyocytes with variable levels of DYRK1A expression. DYRK1A over-expression ameliorated the impact of DAU on beating frequency. This study lays the foundation to further investigate the contribution of variable DYRK1A-TNNT2 expression to Ca handling and beating in human cardiomyocytes.
Topics: Adult; Cardiotoxicity; Daunorubicin; Humans; Induced Pluripotent Stem Cells; Myocytes, Cardiac; Phosphoproteins; Protein Serine-Threonine Kinases; Protein-Tyrosine Kinases; Serine-Arginine Splicing Factors; Troponin T; Dyrk Kinases
PubMed: 35596909
DOI: 10.1007/s12012-022-09746-6 -
Cancer Science Jan 2003The reversing effects of carvedilol and other beta-adrenoceptor antagonists on multidrug resistance (MDR) were assessed in HeLa cells and the MDR1-overexpressing... (Comparative Study)
Comparative Study
The reversing effects of carvedilol and other beta-adrenoceptor antagonists on multidrug resistance (MDR) were assessed in HeLa cells and the MDR1-overexpressing derivative Hvr100-6 cells, established by stepwise increases of vinblastine concentration in the culture medium. The inhibitory effects on the transcellular transport and intracellular accumulation of [3H]vinblastine and [3H]daunorubicin were also assessed using LLC-GA5-COL150 cell monolayers, established by transfection of human MDR1 cDNA into porcine kidney epithelial LLC-PK1 cells. The cytotoxic effects of vinblastine, paclitaxel, doxorubicin and daunorubicin in Hvr100-6 were reversed 1.4- to 7.1-fold by carvedilol at the realistic clinical concentration of 1 microM, whereas other beta-adrenoceptor antagonists had weaker or no such effects. Transport experiments using LLC-GA5-COL150 cell monolayers demonstrated that this effect of carvedilol was due to the inhibition of MDR1-mediated transport of vinblastine, paclitaxel, doxorubicin and daunorubicin. These MDR1-mediated reversing effects of carvedilol were similar to those of 1 microM verapamil, suggesting that carvedilol could be a candidate modulator of MDR in clinical use. Since other beta-adrenoceptor antagonists had no inhibitory effect on transport, the effects of carvedilol were not related to beta-adrenoceptors and might have been due to antioxidant activity.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Adrenergic beta-Antagonists; Animals; Antineoplastic Agents; Biological Transport; Calcium Channel Blockers; Carbazoles; Carvedilol; Cell Division; Cell Line; DNA, Complementary; Daunorubicin; Digoxin; Dose-Response Relationship, Drug; Doxorubicin; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Epithelial Cells; Fluorouracil; HeLa Cells; Humans; Inhibitory Concentration 50; Kidney; Paclitaxel; Propanolamines; Swine; Transfection; Verapamil; Vinblastine
PubMed: 12708479
DOI: 10.1111/j.1349-7006.2003.tb01356.x -
Antimicrobial Agents and Chemotherapy Sep 1980Daunorubicin (daunomycin; NSC 82151) is a fermentation-derived anthracycline antibiotic that is clinically useful in the treatment of human leukemias. Daunorubicin...
Daunorubicin (daunomycin; NSC 82151) is a fermentation-derived anthracycline antibiotic that is clinically useful in the treatment of human leukemias. Daunorubicin itself is found rarely in microbial fermentations, but is present normally in the form of glycoside derivatives that yield the free drug on simple acid hydrolysis. A major by-product of daunorubicin fermentations is usually the structurally related anthracyclinone epsilon-rhodomycinone. We have used mutants of a daunorubicin-producing Streptomyces species to study the biosynthetic relationship between epsilon-rhodomycinone and daunorubicin. We found that exogenously added epsilon-rhodomycinone can be converted to daunorubicin glycosides by a nonproducing mutant and by a mutant that produces daunorubicin glycosides but not epsilon-rhoeomycinone. Molar conversion efficiences were in the 15 to 30% range. The latter mutant was also shown to convert exogenous 14C-labeled epsilon-rhodomycinone to 14C-labeled daunorubicin glycosides, again at conversion efficiencies of about 25%. The same biotransformation was observed with daunorubicin production strain C5, which normally accumulates both epsilon-rhodomycinone and daunorubicin glycosides. A significant percentage (16 to 37%) of exogenously added epsilon-[14C]rhodomycinone was metabolized by strain C5, and 22 to 32% of the metabolized radioactivity could be recovered as daunorubicin glycosides. A mathematical model of epsilon-rhodomycinone metabolism was constructed based on plausible assumptions concerning the kinetics of epsilon-rhodomycinone accumulation and catabolsim. When analyzed according to this model, our data indicate that most (63 to 73%), but not all, of the daunorubicin glycosides accumulated in the experiments with production strain C5 derived from epsilon-rhodomycinone. A pathway network for the biosynthesis of daunorubicin glycosides is proposed that is in agreement with these data. In this proposed pathway network, epsilon-rhodomycinone is an intermediate in one of at least two pathways which yield daunorubicin glycosides.
Topics: Anthracyclines; Daunorubicin; Fermentation; Kinetics; Mutation; Naphthacenes; Species Specificity; Streptomyces
PubMed: 7425613
DOI: 10.1128/AAC.18.3.454 -
Current Protocols in Neuroscience Jul 2016Learned associations about salient experiences (e.g., drug exposure, stress) and their associated environmental stimuli are mediated by a minority of sparsely...
Learned associations about salient experiences (e.g., drug exposure, stress) and their associated environmental stimuli are mediated by a minority of sparsely distributed, behaviorally activated neurons coined 'neuronal ensembles.' For many years, it was not known whether these neuronal ensembles played causal roles in mediating learned behaviors. However, in the last several years the 'Daun02 inactivation technique' in Fos-lacZ transgenic rats has proved very useful in establishing causal links between neuronal ensembles that express the activity-regulated protein Fos and learned behaviors. Fos-expressing neurons in these rats also express the bacterial protein β-galactosidase (β-gal) in strongly activated neurons. When the prodrug Daun02 is injected into the brains of these rats 90 min after a behavior (e.g., drug-seeking) or cue exposure, then Daun02 is converted into daunorubicin by β-gal, which selectively inactivates Fos- and β-gal-expressing neurons that were activated 90 min before the Daun02 injection. This unit presents protocols for breeding the Fos-lacZ rats and conducting appropriate Daun02 inactivation experiments. © 2016 by John Wiley & Sons, Inc.
Topics: Animals; Association Learning; Behavior; Brain; Daunorubicin; Immunohistochemistry; Neurons; Oncogene Proteins v-fos; Rats
PubMed: 27367964
DOI: 10.1002/cpns.2 -
Medical Science Monitor : International... Apr 2004The objective of the present study was in vitro and in vivo investigation of erythrocytes as vehicles for anthracycline antibiotics.
BACKGROUND
The objective of the present study was in vitro and in vivo investigation of erythrocytes as vehicles for anthracycline antibiotics.
MATERIAL/METHODS
The kinetics of daunorubicin binding with erythrocytes was studied in blood and in washed erythrocyte suspensions from healthy donors and patients with acute leukemia. The effect of daunorubicin on erythrocyte deformability was studied using cell filtration through membranes with 3 microm-diameter cylindrical pores. Erythrocyte-bound daunorubicin (EBD), prepared by equilibrating anticoagulated autologous blood with the antibiotic, was administered (45 or 60 mg/m2 body surface) to 14 leukemic patients as part of the 7+ 3 or RACOP courses. The pharmacokinetics of daunorubicin and its tolerability were studied.
RESULTS
Human erythrocytes bound daunorubicin (rubomycin) in citrated whole blood or in washed saline suspension. The equilibrium erythrocyte/medium daunorubicin concentration ratios (attained in 30-60 min at 37 degrees C) averaged 2.9 +/- 0.5 (n=13) in blood and 5.7 +/- 0.6 (n=8) in suspension (p<0.001), without any significant difference between the erythrocytes of donors and patients with acute drug-resistant leukemia or leukemic relapses. Incubation of patient blood with daunorubicin (0.5 mg/ml cells) did not affect erythrocyte deformability (filterability). After intravenous administration, the peak drug concentration and its elimination rate were lower for EBD than for free daunorubicin. The patients tolerated EBD better than its standard free form. In nine patients who received three EBD infusions, side effects were less frequent than in those treated with free daunorubicin.
CONCLUSIONS
Our results indicate that daunorubicin-loaded erythrocytes are promising for clinical application and deserve further clinical study.
Topics: Acute Disease; Adolescent; Adult; Antibiotics, Antineoplastic; Daunorubicin; Erythrocyte Deformability; Erythrocytes; Female; Humans; Leukemia; Male; Middle Aged
PubMed: 15039656
DOI: No ID Found -
International Journal of Molecular... Feb 2021The use of peptide-drug conjugates has generated wide interest as targeted antitumor therapeutics. The anthracycline antibiotic, daunomycin, is a widely used anticancer...
The use of peptide-drug conjugates has generated wide interest as targeted antitumor therapeutics. The anthracycline antibiotic, daunomycin, is a widely used anticancer agent and it is often conjugated to different tumor homing peptides. However, comprehensive analytical characterization of these conjugates via tandem mass spectrometry (MS/MS) is challenging due to the lability of the O-glycosidic bond and the appearance of MS/MS fragment ions with little structural information. Therefore, we aimed to investigate the optimal fragmentation conditions that suppress the prevalent dissociation of the anthracycline drug and provide good sequence coverage. In this study, we comprehensively compared the performance of common fragmentation techniques, such as higher energy collisional dissociation (HCD), electron transfer dissociation (ETD), electron-transfer higher energy collisional dissociation (EThcD) and matrix-assisted laser desorption/ionization-tandem time-of-flight (MALDI-TOF/TOF) activation methods for the structural identification of synthetic daunomycin-peptide conjugates by high-resolution tandem mass spectrometry. Our results showed that peptide backbone fragmentation was inhibited by applying electron-based dissociation methods to conjugates, most possibly due to the "electron predator" effect of the daunomycin. We found that efficient HCD fragmentation was largely influenced by several factors, such as amino acid sequences, charge states and HCD energy. High energy HCD and MALDI-TOF/TOF combined with collision induced dissociation (CID) mode are the methods of choice to unambiguously assign the sequence, localize different conjugation sites and differentiate conjugate isomers.
Topics: Amino Acid Sequence; Daunorubicin; Electron Transport; Peptides; Protein Conformation; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Tandem Mass Spectrometry
PubMed: 33562082
DOI: 10.3390/ijms22041648 -
International Journal of Nanomedicine 2017Due to their specific properties and pharmacokinetics, nanomedicinal products (NMPs) may present different toxicity and side effects compared to non-nanoformulated,... (Meta-Analysis)
Meta-Analysis
Due to their specific properties and pharmacokinetics, nanomedicinal products (NMPs) may present different toxicity and side effects compared to non-nanoformulated, conventional medicines. To facilitate the safety assessment of NMPs, we aimed to gain insight into toxic effects specific for NMPs by systematically analyzing the available toxicity data on approved NMPs in the European Union. In addition, by comparing five sets of products with the same active pharmaceutical ingredient (API) in a conventional formulation versus a nanoformulation, we aimed to identify any side effects specific for the nano aspect of NMPs. The objective was to investigate whether specific toxicity could be related to certain structural types of NMPs and whether a nanoformulation of an API altered the nature of side effects of the product in humans compared to a conventional formulation. The survey of toxicity data did not reveal nanospecific toxicity that could be related to certain types of structures of NMPs, other than those reported previously in relation to accumulation of iron nanoparticles (NPs). However, given the limited data for some of the product groups or toxicological end points in the analysis, conclusions with regard to (a lack of) potential nanomedicine-specific effects need to be considered carefully. Results from the comparison of side effects of five sets of drugs (mainly liposomes and/or cytostatics) confirmed the induction of pseudo-allergic responses associated with specific NMPs in the literature, in addition to the side effects common to both nanoformulations and regular formulations, eg, with liposomal doxorubicin, and possibly liposomal daunorubicin. Based on the available data, immunotoxicological effects of certain NMPs cannot be excluded, and we conclude that this end point requires further attention.
Topics: Albumins; Amphotericin B; Daunorubicin; Doxorubicin; Drug Carriers; Humans; Liposomes; Nanomedicine; Nanoparticles; Nanostructures; Paclitaxel; Polyethylene Glycols; Surveys and Questionnaires
PubMed: 28883724
DOI: 10.2147/IJN.S139687 -
PloS One 2014Alterations in cell cycle regulating proteins are a key characteristic in neoplastic proliferation of lymphoblast cells in patients with Acute Lymphoblastic Leukemia...
Alterations in cell cycle regulating proteins are a key characteristic in neoplastic proliferation of lymphoblast cells in patients with Acute Lymphoblastic Leukemia (ALL). The aim of our study was to investigate whether the routinely administered ALL chemotherapeutic agents would be able to bind and inhibit the key deregulated cell cycle proteins such as--Cyclins E1, D1, D3, A1 and Cyclin Dependent Kinases (CDK) 2 and 6. We used Schrödinger Glide docking protocol to dock the chemotherapeutic drugs such as Doxorubicin and Daunorubicin and others which are not very common including Clofarabine, Nelarabine and Flavopiridol, to the crystal structures of these proteins. We observed that the drugs were able to bind and interact with cyclins E1 and A1 and CDKs 2 and 6 while their docking to cyclins D1 and D3 were not successful. This binding proved favorable to interact with the G1/S cell cycle phase proteins that were examined in this study and may lead to the interruption of the growth of leukemic cells. Our observations therefore suggest that these drugs could be explored for use as inhibitors for these cell cycle proteins. Further, we have also highlighted residues which could be important in the designing of pharmacophores against these cell cycle proteins. This is the first report in understanding the mechanism of action of the drugs targeting these cell cycle proteins in leukemia through the visualization of drug-target binding and molecular docking using computational methods.
Topics: Antineoplastic Agents; Arabinonucleosides; Carcinogenesis; Catalytic Domain; Cell Cycle Checkpoints; Cell Cycle Proteins; Curcumin; Daunorubicin; Doxorubicin; Humans; Hydrogen Bonding; Molecular Docking Simulation; Molecular Targeted Therapy; Precursor Cell Lymphoblastic Leukemia-Lymphoma
PubMed: 24454966
DOI: 10.1371/journal.pone.0086310 -
Journal of Pharmacy & Pharmaceutical... 2007The effect of CCl4-induced experimental hepatic injury (CCl4-EHI) on the pharmacokinetics of daunorubicin was investigated systemically in rats, in an attempt to... (Comparative Study)
Comparative Study
PURPOSE
The effect of CCl4-induced experimental hepatic injury (CCl4-EHI) on the pharmacokinetics of daunorubicin was investigated systemically in rats, in an attempt to elucidate the major determinants of the effect of CCl4-EHI on the pharmacokinetics of the drug.
METHODS
CCl4-EHI was induced in rats by a single intraperitoneal injection of CCl4 (1 mL/kg rat), and a 24 h fasting period. Daunorubicin was administered intravenously to control and EHI rats at a dose of 11.3 mg/mL/kg and the in vivo pharmacokinetics was studied. The in vitro uptake of the drug into isolated hepatocytes and canalicular liver plasma membrane (cLPM) vesicles, as well as the liver microsomal degradation of the drug, were also determined.
RESULTS
The area under the plasma concentration-time curve (AUC) of daunorubicin was increased by 1.6 times, resulting in a 34% decrease in the systemic clearance (CL) in rats with CCl4-EHI. The apparent biliary (CLbile) and urinary (CLurine) clearance of the drug were unchanged, whereas the AUC of daunorubicinol, the major metabolite of daunorubicin, was decreased by 66% in rats with CCl4-EHI. EHI seemed to affect the hepatobiliary elimination of the drug in several ways: the in vitro intrinsic sinusoidal uptake clearance was decreased by 20%; the in vitro intrinsic canalicular excretion clearance of the drug was increased by 1.7 times; and the in vitro liver microsomal degradation of daunorubicin was significantly retarded.
CONCLUSIONS
CCl4-EHI appears to impair the hepatic metabolism of daunorubicin, thereby decreasing the CL and increasing the AUC of daunorubicin.
Topics: Animals; Carbon Tetrachloride Poisoning; Chemical and Drug Induced Liver Injury; Daunorubicin; Liver Diseases; Male; Microsomes, Liver; Rats; Rats, Sprague-Dawley
PubMed: 18261366
DOI: 10.18433/j3mw28 -
International Journal of Molecular... Sep 2019Among various homing devices, gonadotropin-releasing hormone-III (GnRH-III) peptide represents a suitable targeting moiety for drug delivery systems. The anti-tumor...
Among various homing devices, gonadotropin-releasing hormone-III (GnRH-III) peptide represents a suitable targeting moiety for drug delivery systems. The anti-tumor activity of the previously developed GnRH-III-[Lys(Bu),Lys(Dau=Aoa)] conjugate and the novel synthesized GnRH-III-[ΔHis,d-Tic,Lys(Bu),Lys(Dau=Aoa)] conjugate, containing the anti-cancer drug daunorubicin, were evaluated. Here, we demonstrate that both GnRH-III-Dau conjugates possess an efficient growth inhibitory effect on more than 20 cancer cell lines, whereby the biological activity is strongly connected to the expression of gonadotropin-releasing hormone receptors (GnRH-R). The novel conjugate showed a higher in vitro anti-proliferative activity and a higher uptake capacity. Moreover, the treatment with GnRH-III-Dau conjugates cause a significant in vivo tumor growth and metastases inhibitory effect in three different orthotopic models, including 4T1 mice and MDA-MB-231 human breast carcinoma, as well as HT-29 human colorectal cancer bearing BALB/s and SCID mice, while toxic side-effects were substantially reduced in comparison to the treatment with the free drug. These findings illustrate that our novel lead compound is a highly promising candidate for targeted tumor therapy in both colon cancer and metastatic breast cancer.
Topics: Animals; Female; Humans; Mice; Antineoplastic Agents; Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Colorectal Neoplasms; Daunorubicin; Disease Models, Animal; Gene Expression; Gonadotropin-Releasing Hormone; Molecular Structure; Pyrrolidonecarboxylic Acid; Receptors, Cell Surface; RNA, Messenger; Toxicity Tests; Xenograft Model Antitumor Assays
PubMed: 31557968
DOI: 10.3390/ijms20194763