Pharmacokinetic herb-drug interactions between Aidi injection and doxorubicin in rats with diethylnitrosamine-induced hepatocellular carcinoma.

BACKGROUND: Aidi Injection (ADI), a Chinese herbal preparation with anti-cancer activity, is used for the treatment of hepatocellular carcinoma (HCC). Several clinical studies have shown that co-administration of ADI with doxorubicin (DOX) is associated with reduced toxicity of chemotherapy, enhanced clinical efficacy and improved quality of life for patients. However, limited information is available about the herb-drug interactions between ADI and DOX. The study aimed to investigate the pharmacokinetic mechanism of herb-drug interactions between ADI and DOX in a rat model of HCC. METHODS: Experimental HCC was induced in rats by oral administration of diethylnitrosamine. The HCC rats were pretreated with ADI (10 mL/kg, intraperitoneal injection) for 14 consecutive days prior to administration of DOX (7 mg/kg, intravenous injection) to investigate pharmacokinetic interactions. Plasma concentrations of DOX and its major metabolite, doxorubicinol (DOXol), were determined using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). RESULTS: Preadministration of ADI significantly altered the pharmacokinetics of DOX in HCC rats, leading to increased plasma concentrations of both DOX and DOXol. The area under the plasma drug concentration-time curve (AUCs) of DOX and DOXol in rats pretreated with ADI were 3.79-fold and 2.92-fold higher, respectively, than those in control rats that did not receive ADI. CONCLUSIONS: Increased levels of DOX and DOXol were found in the plasma of HCC rats pretreated with ADI.

Next generation risk assessment (NGRA): Bridging in vitro points-of-departure to human safety assessment using physiologically-based kinetic (PBK) modelling - A case study of doxorubicin with dose metrics considerations.

Using the chemical doxorubicin (DOX), the objective of the present study was to evaluate the impact of dose metrics selection in the new approach method of integrating physiologically-based kinetic (PBK) modelling and relevant human cell-based assays to inform a priori the point of departure for human health risk. We reviewed the literature on the clinical consequences of DOX treatment to identify dosing scenarios with no or mild cardiotoxicity observed. Key concentrations of DOX that induced cardiomyocyte toxicity in vitro were derived from studies of our own and others. A human population-based PBK model of DOX was developed and verified against pharmacokinetic data. The model was then used to predict plasma and extracellular and intracellular heart concentrations of DOX under selected clinical settings and compared with in vitro outcomes, based on several dose metrics: Cmax (maximum concentration) or AUC (area under concentration-time curve) in free or total form of DOX. We found when using in vitro assays to predict cardiotoxicity for DOX, AUC is a better indicator. Our study illustrates that when appropriate dose metrics are used, it is possible to combine PBK modelling with in vitro-derived toxicity information to define margins of safety and predict low-risk human exposure levels.

Doxorubicin delivery systems based on doped CaCO3 cores and polyanion drug conjugates.

In order to prolong the release and reduce the toxicity of anticancer drug - doxorubicin (DOX), delivery systems (DS) using different polyanions have been developed. Structural (size, morphological stability) and functional (encapsulation efficiency, DOX release) characteristics of three types of DS are compared: CaCO3 porous vaterites doped with polyanions by co-precipitation and coating techniques, and DOX-polyanion conjugates. Using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), it was shown that the doping enhances the morphological stability of CaCO3-based DS during the DOC loading. Doping of CaCO3 cores by co-precipitation reduces its sizes (up to 1 µm) and DOX encapsulation efficiency. Polyanion-coated CaCO3 cores and polyanion drug conjugates show about 98 w/w% DOX encapsulation. For the first time, it was shown that the release of DOX from developed DS into human blood plasma is more intense (from 1.3 to 3.0 times for different DS) than into model tumour environment.

Sensitive Analysis of Idarubicin in Human Urine and Plasma by Liquid Chromatography with Fluorescence Detection: An Application in Drug Monitoring.

A new approach for the sensitive, robust and rapid determination of idarubicin (IDA) in human plasma and urine samples based on liquid chromatography with fluorescence detection (LC-FL) was developed. Satisfactory chromatographic separation of the analyte after solid-phase extraction (SPE) was performed on a Discovery HS C18 analytical column using a mixture of acetonitrile and 0.1% formic acid in water as the mobile phase in isocratic mode. IDA and daunorubicin hydrochloride used as an internal standard (I.S.) were monitored at the excitation and emission wavelengths of 487 and 547 nm, respectively. The method was validated according to the FDA and ICH guidelines. The linearity was confirmed in the range of 0.1-50 ng/mL and 0.25-200 ng/mL, while the limit of detection (LOD) was 0.05 and 0.125 ng/mL in plasma and urine samples, respectively. The developed LC-FL method was successfully applied for drug determinations in human plasma and urine after oral administration of IDA at a dose of 10 mg to a patient with highly advanced alveolar rhabdomyosarcoma (RMA). Moreover, the potential exposure to IDA present in both fluids for healthcare workers and the caregivers of patients has been evaluated. The present LC-FL method can be a useful tool in pharmacokinetic and clinical investigations, in the monitoring of chemotherapy containing IDA, as well as for sensitive and reliable IDA quantitation in biological fluids.

Analysis of the Doxorubicin and Doxorubicinol in the Plasma of Breast Cancer Patients for Monitoring the Toxicity of Doxorubicin.

INTRODUCTION: Doxorubicin is an anthracycline antibiotic used as an anticancer agent. Long-term use of this anticancer agent could accumulate its metabolite, doxorubicinol, and cause cardiomyopathy, due to its cardiotoxicity. This cardiotoxic effect depends on the amount of doxorubicin and doxorubicinol accumulated in the body. This study aimed to analyze doxorubicin and doxorubicinol levels in the blood plasma of breast cancer patients. METHODS: Participants of this study were 30 breast cancer patients who had received doxorubicin in their therapy regimen. The samples were analyzed using ultra-high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS), with the Acquity UPLC BEH C18 Waters chromatography column (2.1 x 100 mm : 1.7 µm). Plasma (250 µL) samples were prepared by protein precipitation, using methanol. The mobile phase consisted of 0.1% acetic acid (eluent A) and acetonitrile (eluent B), with gradient elution; the flow rate was 0.15 mL/min and runtime, 7 min. RESULTS AND DISCUSSION: This method was linear in the range of 1-1000 ng/mL for doxorubicin and 0.5-500 ng/mL for doxorubicinol. This method was successfully used to analyze doxorubicin and doxorubicinol, simultaneously, using hexamethylphosphoramide as the internal standard, in the plasma of breast cancer patients. Results showed that the measured concentrations of doxorubicin and doxorubicinol ranged between 12.54-620.01 ng/mL and 1.10-27.00 ng/mL, respectively. The measured cumulative doses of doxorubicin ranged between 48.76 and 319.01 mg/m2; thus, the risk of cardiomyopathy in the surveyed patients was under 4%, according to literature.

A Novel Long-circulating DOX Liposome: Formulation and Pharmacokinetics Studies.

BACKGROUND: Doxorubicin (DOX) is a leading chemotherapeutic in cancer treatment because of its high potency and broad spectrum. Liposomal doxorubicin (Doxil®) is the first FDA-approved PEG-liposomes of DOX for the treatment of over 600,000 cancer patients, and it can overcome doxorubicin-induced cardiomyopathy and other side effects and prolong life span. The addition of MPEG2000-DSPE could elevate the total cost of cancer treatment. OBJECTIVE: We intended to prepare a novel DOX liposome that was prepared with inexpensive materials egg yolk lecithin and Kolliphor HS15, thus allowing it to be much cheaper for clinical application. METHODS: DOX liposomes were prepared using the combination of thin-film dispersion ultrasonic method and ammonium sulfate gradient method and the factors that influenced formulation quality were optimized. After formulation, particle size, entrapment efficiency, drug loading, stability, and pharmacokinetics were determined. RESULTS: DOX liposomes were near-spherical morphology with the average size of 90 nm and polydispersity index (PDI) of less than 0.30. The drug loading was up to 7.5%, and the entrapment efficiency was over 80%. The pharmacokinetic studies showed that free DOX could be easily removed and the blood concentration of free DOX group was significantly lower than that of DOX liposomes, which indicated that the novel DOX liposome had a certain sustainedrelease effect. CONCLUSION: In summary, DOX liposome is economical and easy-prepared with prolonged circulation time. Lay Summary: Doxorubicin (DOX) is a leading chemotherapeutic in cancer treatment because of its high potency and broad spectrum. Liposomal doxorubicin (Doxil®) is the first FDAapproved PEG-liposomes of DOX to treat over 600.000 cancer patients, overcoming doxorubicin- induced cardiomyopathy and other side effects and prolonging life span. The addition of MPEG2000-DSPE could elevate the total cost of cancer treatment. We intend to prepare a novel DOX liposome prepared with inexpensive materials egg yolk lecithin and Kolliphor HS15, thus allowing it to be much cheaper for clinical use. The novel DOX liposome is economical and easy-prepared with prolonged circulation time.

Can we optimise doxorubicin treatment regimens for children with cancer? Pharmacokinetic simulations and a Delphi consensus procedure.

BACKGROUND: Despite its cardiotoxicity doxorubicin is widely used for the treatment of paediatric malignancies. Current treatment regimens appear to be suboptimal as treatment strategies vary and do not follow a clear pharmacological rationale. Standardisation of dosing strategies in particular for infants and younger children is required but is hampered by scarcely defined exposure-response relationships. The aim is to provide a rational dosing concept allowing for a reduction of variability in systemic therapy intensity and subsequently unforeseen side effects. METHODS: Doxorubicin plasma concentrations in paediatric cancer patients were simulated for different treatment schedules using a population pharmacokinetic model which considers age-dependent differences in doxorubicin clearance. Overall drug exposure and peak concentrations were assessed. Simulation results were used to support a three round Delphi consensus procedure with the aim to clarify the pharmacological goals of doxorubicin dosing in young children. A group of 28 experts representing paediatric trial groups and clinical centres were invited to participate in this process. RESULTS: Pharmacokinetic simulations illustrated the substantial differences in therapy intensity associated with current dosing strategies. Consensus among the panel members was obtained on a standardised a priori dose adaptation that individualises doxorubicin doses based on age and body surface area targeting uniform drug exposure across children treated with the same protocol. Further, a reduction of peak concentrations in very young children by prolonged infusion was recommended. CONCLUSIONS: An approach to standardise current dose modification schemes in young children is proposed. The consented concept takes individual pharmacokinetic characteristics into account and involves adaptation of both the dose and the infusion duration potentially improving the safety of doxorubicin administration.

Interspecies prediction of pharmacokinetics and tissue distribution of doxorubicin by physiologically-based pharmacokinetic modeling.

The aim of the study was to develop a physiologically-based pharmacokinetic (PBPK) model to describe and predict whole-body disposition of doxorubicin following intravenous administration. The PBPK model was established using previously published data in mice and included 10 tissue compartments: lungs, heart, brain, muscle, kidneys, pancreas, intestine, liver, spleen, adipose tissue, and plasma. Individual tissues were described by either perfusion-limited or permeability-limited models. All parameters were simultaneously estimated and the final model was able to describe murine data with good precision. The model was used for predicting doxorubicin disposition in rats, rabbits, dogs, and humans using interspecies scaling approaches and was qualified using plasma and tissue observed data. Reasonable prediction of the plasma pharmacokinetics and tissue distribution was achieved across all species. In conclusion, the PBPK model developed based on a rich dataset obtained from mice, was able to reasonably predict the disposition of doxorubicin in other preclinical species and humans. Applicability of the model for special populations, such as patients with hepatic impairment, was also demonstrated. The proposed model will be a valuable tool for optimization of exposure profiles of doxorubicin in human patients.

Liquid Chromatography-Tandem Mass Spectrometry for the Simultaneous Determination of Doxorubicin and its Metabolites Doxorubicinol, Doxorubicinone, Doxorubicinolone, and 7-Deoxydoxorubicinone in Mouse Plasma.

Doxorubicin, an anthracycline antitumor antibiotic, acts as a cancer treatment by interfering with the function of DNA. Herein, liquid chromatography-tandem mass spectrometry was for the first time developed and validated for the simultaneous determination of doxorubicin and its major metabolites doxorubicinol, doxorubicinone, doxorubicinolone, and 7-deoxydoxorubicinone in mouse plasma. The liquid-liquid extraction of a 10 µL mouse plasma sample with chloroform:methanol (4:1, v/v) and use of the selected reaction monitoring mode led to less matrix effect and better sensitivity. The lower limits of quantification levels were 0.5 ng/mL for doxorubicin, 0.1 ng/mL for doxorubicinol, and 0.01 ng/mL for doxorubicinone, doxorubicinolone, and 7-deoxydoxorubicinone. The standard curves were linear over the range of 0.5-200 ng/mL for doxorubicin; 0.1-200 ng/mL for doxorubicinol; and 0.01-50 ng/mL for doxorubicinone, doxorubicinolone, and 7-deoxydoxorubicinone in mouse plasma. The intra and inter-day relative standard deviation and relative errors for doxorubicin and its four metabolites at four quality control concentrations were 0.9-13.6% and -13.0% to 14.9%, respectively. This method was successfully applied to the pharmacokinetic study of doxorubicin and its metabolites after intravenous administration of doxorubicin at a dose of 1.3 mg/kg to female BALB/c nude mice.

Preparation and in vitro/in vivo evaluation of doxorubicin-loaded poly[lactic-co-glycol acid] microspheres using electrospray method for sustained drug delivery and potential intratumoral injection.

For cancer treatment, intratumoral drug injection has many limitations and not commonly adopted. The poly[lactic-co-glycolic acid] (PLGA) has emerged as a promising vehicle to enhance the in vitro/in vivo characteristic of various drugs. We prepared doxorubicin-PLGA microspheres (DOX-PLGA MSs) using the electrospray method. An in vitro elution method was employed to evaluate the release of DOX from the MSs. We performed an in vivo study on rats, in which we directly injected DOX-PLGA MSs into the liver. We measured liver and plasma DOX concentrations to assess local retention and systemic exposure. The mean diameter of the MSs was 6.74 ±â€¯1.01 µm. The in vitro DOX release from the MSs exhibited a 12.3 % burst release on day 1, and 85.8 % of the drug had been released after 30 days. The in vivo tests revealed a higher local drug concentration at the target lobe of the liver than at the adjacent median lobe. In the first week, the DOX concentration in the peripheral blood of the MS group was lower than that of the direct DOX injection group. Based on the measured intrahepatic concentration and plasma pharmacokinetic profiles, DOX-PLGA MSs could be suitable vectors of chemotoxic agents for intratumoral injection.

Pharmacokinetics of mitomycin-c lipidic prodrug entrapped in liposomes and clinical correlations in metastatic colorectal cancer patients.

Background Pegylated liposomal (PL) mitomycin-c lipidic prodrug MLP) may be a useful agent in patients with metastatic colo-rectal carcinoma (CRC). We report here on the pharmacokinetics and clinical observations in a phase 1A/B study with PL-MLP. Methods Plasma levels of MLP were examined in 53 CRC patients, who received PL-MLP either as single agent or in combination with capecitabine and/or bevacizumab. MLP was determined by an HPLC-UV assay, and its pharmacokinetics was analyzed by noncompartmental methods. The correlation between clinical and pharmacokinetic parameters was statistically analyzed. Results PL-MLP was well tolerated with a good safety profile as previously reported. Stable Disease was reported in 15/36 (42%) of efficacy-evaluable patients. Median survival of stable disease patients (14.4 months) was significantly longer than of progressive disease patients (6.5 months) and non-evaluable patients (2.3 months). MLP pharmacokinetics was stealth-like with long T½ (~1 day), slow clearance, and small volume of distribution (Vd). The addition of capecitabine and/or bevacizumab did not have any apparent effect on the pharmacokinetics of MLP and clinical outcome. High baseline neutrophil count and CEA level were correlated with faster clearance, and larger Vd. Stable disease patients had longer T½ and slower clearance than other patients. T½ and clearance were significantly correlated with survival. Conclusions PL-MLP treatment results in a substantial rate of disease stabilization in metastatic CRC, and prolonged survival in patients achieving stable disease. The correlation of neutrophil count and CEA level with pharmacokinetic parameters of MLP is an unexpected finding that needs further investigation. The association of long T½ of MLP with stable disease and longer survival is consistent with an improved probability of disease control resulting from enhanced tumor localization of long-circulating liposomes and underscores the relevance of personalized pharmacokinetic evaluation in the use of nanomedicines.

Use of a Glass Membrane Pumping Emulsification Device Improves Systemic and Tumor Pharmacokinetics in Rabbit VX2 Liver Tumor in Transarterial Chemoembolization.

PURPOSE: To evaluate the phamacokinetics of epirubicin in conventional transarterial chemoembolization using a developed pumping emulsification device with a microporous glass membrane in VX2 rabbits. MATERIALS AND METHODS: Epirubicin solution (10 mg/mL) was mixed with ethiodized oil (1:2 ratio) using the device or 3-way stopcock. Forty-eight rabbits with VX2 liver tumor implanted 2 weeks prior to transarterial chemoembolization were divided into 2 groups: a device group (n = 24) and a 3-way-stopcock group (n = 24). Next, 0.5 mL of emulsion was injected into the hepatic artery, followed by embolization using 100-300-µm microspheres. The serum epirubicin concentrations (immediately after, 5 minutes after, and 10 minutes after) and the tumor epirubicin concentrations (20 minutes after and 48 hours after) were measured after transarterial chemoembolization. Histopathologic evaluation was performed with a fluorescence microscope. RESULTS: The area under the curve and maximum concentrations of epirubicin in plasma were 0.45 ± 0.18 µg min/mL and 0.13 ± 0.06 µg/mL, respectively, in the device group and 0.71 ± 0.45 µg min/mL and 0.22 ± 0.17 µg/mL, respectively, in the 3-way-stopcock group (P = .013 and P = .021, respectively). The mean epirubicin concentrations in VX2 tumors at 48 hours in the device group and the 3-way-stopcock group were 13.7 ± 6.71 and 7.72 ± 3.26 µg/g tissue, respectively (P = .013). The tumor necrosis ratios at 48 hours were 62 ± 11% in the device group and 51 ± 13% in the 3-way-stopcock group (P = .039). CONCLUSIONS: Conventional transarterial chemoembolization using the pumping emulsification device significantly improved the pharmacokinetics of epirubicin compared to the current standard technique using a 3-way stopcock.

Development and validation of a high-performance liquid chromatographic method with a fluorescence detector for the analysis of epirubicin in human urine and plasma, and its application in drug monitoring.

The aim of the work was to develop a simple, sensitive and accurate liquid chromatography with fluorescence detection (LC-FL) method for the determination of epirubicin in human urine and plasma. Solid phase extraction with HLB cartridges and mixture of dichloromethane:2-propanol:methanol (2:1:1, v/v/v) as the eluent, was used to prepare the samples. The chromatographic analysis was carried out on a Synergi Hydro-RP column with a mobile phase consisting of 40 mM phosphate buffer (pH 4.1) and acetonitrile (69:31, v/v). Epirubicin was monitored at 497 nm and 557 nm for excitation and emission wavelengths, respectively. Validation data confirmed that the limit of detection and limit of quantification was 0.25 ng/mL and 0.5 ng/mL in both matrices. Next, the optimized LC-FL method was applied to determine the level of epirubicin in real samples taken from a 19-year-old patient with metastatic alveolar rhabdomyosarcoma (RMA) to create a drug profile. Plasma and urine samples were collected for 24 h after the end of a 6-hour infusion of epirubicin. The obtained results confirmed that the optimized and validated LC-FL method can be successfully used in drug monitoring therapy, pharmacokinetic and clinical studies. Moreover, the current work is also drawing attention to the relatively high level of epirubicin in the patient urine, which requires compliance with the safety rules in contact with this biological fluid by both medical staff and others, e.g. family members.

Identification of differential gene expression related to epirubicin-induced cardiomyopathy in breast cancer patients.

BACKGROUND: Epirubicin is a potent chemotherapeutic agent for the treatment of breast cancer. However, it may lead to cardiotoxicity and cardiomyopathy, and no reliable biomarker was available for the early prediction of epirubicin-induced cardiomyopathy. METHODS: Global gene expression changes of peripheral blood cells were studied using high-throughput RNA sequencing in three pair-matched breast cancer patients (patients who developed symptomatic cardiomyopathy paired with patients who did not) before and after the full session of epirubicin-based chemotherapy. Functional analysis was conducted using gene ontology and pathway enrichment analysis. RESULTS: We identified 13 significantly differentially expressed genes between patients who developed symptomatic epirubicin-induced cardiomyopathy and their paired control who did not. Among them, the upregulated Bcl-associated X protein was related to "apoptosis," while the downregulated 5'-aminolevulinate synthase 2 (ALAS2) was related to both "glycine, serine, and threonine metabolism" and "porphyrin and chlorophyll metabolism" in pathway enrichment analysis. CONCLUSIONS: ALAS2 and the metabolic pathways which were involved may play an important role in the development of epirubicin-induced cardiomyopathy. ALAS2 may be useful as an early biomarker for epirubicin-induced cardiotoxicity detection.

Development of a high-precision bladder hyperthermic intracavitary chemotherapy device for bladder cancer and pharmacokinetic study.

BACKGROUND: Bladder hyperthermic intracavitary chemotherapy (HIVEC) has good effectiveness for bladder cancer, but conventional HIVEC systems lack precision and convenient application. To test the safety of a new HIVEC device (BR-TRG-II-type) in pigs and to perform a preliminary clinical trial in patients with bladder cancer. METHODS: This device was tested on six pigs to optimize the temperature and time parameters. Then, 165 patients (HIVEC after transurethral resection (TUR), n = 128; or HIVEC, n = 37) treated between December 2006 and December 2016 were recruited. Mitomycin C (MMC) was the chemotherapeutic agent. A serum pharmacokinetic study was performed. The primary endpoints were tumor recurrence, disease-free survival (DFS), and cumulative incidence rate (CIR) during follow-up. The adverse effects were graded. RESULTS: The animal experiment showed that 45 °C for 1 h was optimal. HIVEC was successful, with the infusion tube temperature stably controlled at about 45 °C, and outlet tube temperature of about 43 °C in all patients, for three sessions. Serum MMC levels gradually increased during HIVEC and decreased thereafter. The mean DFS was 39 ± 3.21 months (ranging from 8 to 78 months), and the DFS rate was 89.1% during follow-up. No adverse events occurred. CONCLUSION: The use of the BR-TRG-II-type HIVEC device is feasible for the treatment of bladder cancer. Future clinical trials in patients with different stages of bladder cancer will further confirm the clinical usefulness of this device. TRIAL REGISTRATION: chictr.org.cn: ChiCTR1900022099 (registered on Mar. 252,019). Retrospectively registered.

Real-time fluorescence imaging for visualization and drug uptake prediction during drug delivery by thermosensitive liposomes.

Objective: Thermosensitive liposomal doxorubicin (TSL-Dox) is a promising stimuli-responsive nanoparticle drug delivery system that rapidly releases the contained drug in response to hyperthermia (HT) (>40 °C). Combined with localized heating, TSL-Dox allows highly localized delivery. The goals of this study were to demonstrate that real-time fluorescence imaging can visualize drug uptake during delivery, and can predict tumor drug uptake. Methods: Nude mice carrying subcutaneous tumors (Lewis lung carcinoma) were anesthetized and injected with TSL-Dox (5 mg/kg dose). Localized HT was induced by heating tumors for 15, 30 or 60 min via a custom-designed HT probe placed superficially at the tumor location. In vivo fluorescence imaging (excitation 523 nm, emission 610 nm) was performed before, during, and for 5 min following HT. After imaging, tumors were extracted, drug uptake was quantified by high-performance liquid chromatography, and correlated with in vivo fluorescence. Plasma samples were obtained before and after HT to measure TSL-Dox pharmacokinetics. Results: Local drug uptake could be visualized in real-time during HT. Compared to unheated control tumors, fluorescence of heated tumors increased by 4.6-fold (15 min HT), 9.3-fold (30 min HT), and 13.2-fold (60 min HT). HT duration predicted tumor drug uptake (p = .02), with tumor drug concentrations of 4.2 ± 1.3 µg/g (no HT), 7.1 ± 5.9 µg/g (15 min HT), 14.1 ± 6.7 µg/g (30 min HT) and 21.4 ± 12.6 µg/g (60 min HT). There was good correlation (R2 = 0.67) between fluorescence of the tumor region and tumor drug uptake. Conclusions: Real-time in vivo fluorescence imaging can visualize drug uptake during delivery, and can predict tumor drug uptake.

Simultaneous voltammetric determination of glutathione, doxorubicin and tyrosine based on the electrocatalytic effect of a nickel(II) complex and of Pt:Co nanoparticles as a conductive mediator.

Glutathione (GSH) is an important tripeptide that plays an important role in preventing damage to reactive oxygen species. An electrochemical assay was fabricated for this purpose by modification of a carbon paste electrode (CPE) with bis(1,10-phenanthroline)(1,10-phenanthroline-5,6-dione)nickel(II) hexafluorophosphate (BPPDNi) as new electro-catalyst and Pt:Co nanoparticle (Pt:CO-NPs) as highly conductive mediator. The analyses were performed at a scan rate of 10 mV/s and at a pH value of 7.4. The BPPDNi/Pt:CO-NPs/CPE showed a high sensitivity and good selectivity for electro-catalytic determination of glutathione (GSH) in nano-molar concentration range. In addition, the BPPDNi/Pt:CO-NPs/CPE was used for the determination of glutathione in the presence of doxorubicin (DOX) and tyrosine (Tyr) with three separated oxidation signals ~160 mV, ~385 mV and ~790 mV vs. Ag/AgCl/KClsat, respectively. The peak currents of the square wave voltammetric analyses were linearly dependent on glutathione, doxorubicin and tyrosine concentrations in the respective ranges of 0.001-450, 0.5-300 and 1.0-650 µM, with detection limits of 0.5 nM, 0.1 µM and 0.6 µM, respectively. Graphical abstract The first analytical sensor for simultaneous determination of glutathione, doxorubicin and tyrosine.

Doxorubicin-induced testicular damage is related to PARP-1 signaling molecules in mice.

BACKGROUND: Doxorubicin (DOX), is a chemotherapeutic agent, which evokes oxidative stress and cell apoptosis in testicular tissue. It is known that the activation of the nuclear enzyme poly (ADP-ribose) polymerase (PARP), leading to apoptosis induced by DOX. The aim of the present study is to investigate whether PARP pathway has a role in DOX-induced testicular damage and infertility utilizing pharmacological PARP-1 inhibitor, PJ34, and PARP-1 knockout mice model. METHODS: Firstly, we assessed the activation of PARP pathway after DOX-induction at various hours by immunohistochemistry and western blot analysis. Secondly, we evaluated the role of PARP pathway in DOX-induced testicular damage, sperm motility, and fertility with pharmacological inhibition of PARP by using PJ34. Finally, we aimed to correlate a functional relationship between PARP-1 and DOX using PARP-1 knockout mice in DOX-induced testicular damage. Doxorubicin levels in plasma and testis tissue were also assessed. RESULTS: In DOX-induced group; PARP-1, PAR and apoptotic pathway protein expressions, increased significantly. In DOX + PJ34 group; PAR, cytochrome c, and AIF levels decreased significantly. Testicular weights, sperm motility, and mean the number of pups per litter decreased in DOX-induced group after 28 days, however they were similar to the control group in DOX-PJ34 group. In PARP-1 KO group, seminiferous tubule morphology was impaired significantly after 28 days of DOX-administration. CONCLUSIONS: Our study indicates that DOX-induced testicular damage may be related to over-activation of PARP-1. PJ34 application was effective in preventing severe testicular damage caused by DOX-injection and may be considered for fertility protection against DOX-induced testicular damage.

Graphene-modified electrodes for sensing doxorubicin hydrochloride in human plasma.

Doxorubicin (DOX), an anthracycline molecule, is currently one of the most widely used anticancer drugs in clinics. Systematic treatment of patients with DOX is known to be accompanied by several unpleasant side effects due to the toxicity of the drug. Thus, monitoring of DOX concentration in serum samples has become increasingly important to avoid side effects and ensure therapeutic efficiency. In this study, we discuss the construction of a disposable electrochemical sensor for the direct monitoring of DOX in clinical blood samples. The sensor is based on coating a gold electrode in a flexible integrated electrode construct formed on polyimide sheets using photolithography, with nitrogen-doped reduced graphene oxide (N-rGO) suspended in chitosan. Under optimized conditions, a linear relationship between the oxidative peak current and the concentration of DOX in the range of 0.010-15 µM with a detection limit of 10 nM could be achieved. The sensor was adapted to monitor DOX in serum samples of patients under anticancer treatment. Graphical abstract.

Doxorubicin area under the curve is an important predictor of neutropenia in dogs with naturally occurring cancers.

Doxorubicin (DOX) area-under-the-curve (AUC) was calculated for 40 dogs with spontaneously occurring cancers using a previously validated limited-sampling approach. All dogs were administered a dose of 30 mg/m2 by intravenous infusion and serum samples were collected at 5, 45 and 60 minutes post-infusion. DOX and its major metabolite, doxorubicinol (doxol), were quantified in serum samples using high-performance liquid chromatography tandem-mass spectrometry. Wide interpatient variability was observed in the predicted DOX AUC with a coefficient of variation of 34%. A significant relationship was found between DOX AUC and absolute white blood cell count (P = 0.003), absolute neutrophil count (ANC; P = 0.002) and surviving fraction of neutrophils (P = 0.03) approximately 1 week after dosing (nadir). No changes in other hematologic parameters (red blood cells, platelets, lymphocytes, haemoglobin) were found to correlate with DOX AUC. The absolute dose (mg) and the dose per unit body weight (mg/kg) were not significantly correlated with nadir ANC. No relationships were found between maximum serum doxol concentration and myelosuppression. Baseline ANC was also significantly correlated to nadir ANC and a model was constructed using baseline ANC and DOX AUC that significantly described the nadir ANC. These findings demonstrate the important relationship between systemic DOX exposure and degree of neutropenia in dogs, and suggest a potential for individualized, pharmacokinetically-guided DOX dosing in dogs.