scholarly journals Nevirapine Biotransformation Insights: An Integrated In Vitro Approach Unveils the Biocompetence and Glutathiolomic Profile of a Human Hepatocyte-Like Cell 3D Model

2020 ◽  
Vol 21 (11) ◽  
pp. 3998 ◽  
Author(s):  
Madalena Cipriano ◽  
Pedro F Pinheiro ◽  
Catarina O Sequeira ◽  
Joana S Rodrigues ◽  
Nuno G Oliveira ◽  
...  
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
3D Model ◽  
Toxicological Assessment ◽  
Biotransformation Enzymes ◽  
Net Flux ◽  
Hepatotoxic Drug ◽  
Phase I And Ii ◽  
3D Spheroids

The need for competent in vitro liver models for toxicological assessment persists. The differentiation of stem cells into hepatocyte-like cells (HLC) has been adopted due to its human origin and availability. Our aim was to study the usefulness of an in vitro 3D model of mesenchymal stem cell-derived HLCs. 3D spheroids (3D-HLC) or monolayer (2D-HLC) cultures of HLCs were treated with the hepatotoxic drug nevirapine (NVP) for 3 and 10 days followed by analyses of Phase I and II metabolites, biotransformation enzymes and drug transporters involved in NVP disposition. To ascertain the toxic effects of NVP and its major metabolites, the changes in the glutathione net flux were also investigated. Phase I enzymes were induced in both systems yielding all known correspondent NVP metabolites. However, 3D-HLCs showed higher biocompetence in producing Phase II NVP metabolites and upregulating Phase II enzymes and MRP7. Accordingly, NVP-exposure led to decreased glutathione availability and alterations in the intracellular dynamics disfavoring free reduced glutathione and glutathionylated protein pools. Overall, these results demonstrate the adequacy of the 3D-HLC model for studying the bioactivation/metabolism of NVP representing a further step to unveil toxicity mechanisms associated with glutathione net flux changes.

Role of Phase II Enzymes in the Bioactivation of 1,4-Dichlorobenzene and 1,4-Dibromobenzene

1996 ◽  
Vol 24 (4) ◽  
pp. 603-608
Author(s):  
Moreno Paolini ◽  
Laura Pozzetti ◽  
Renata Mesirca ◽  
Andrea Sapone ◽  
Paola Silingardi ◽  
...  
Keyword(s):  
Dna Binding ◽  
Phase I ◽  
Phase Ii ◽  
Covalent Binding ◽  
Fold Increase ◽  
Test System ◽  
Oxidative Enzymes ◽  
Transferase Activity ◽  
Genetic Toxicology

The use of sodium phenobarbital (PB, CYP2B1 inducer) combined with β-naphthoflavone (β-NF, 1A1) to induce certain Phase I reactions in S9 liver fractions is a standard method for conducting short-term bioassays for genotoxicity. However, because post-oxidative enzymes are also able to activate many precarcinogens, we tested the possibility of adapting S9 liver fractions derived from Phase II-induced rodents to the field of genetic toxicology. In this study, S9 liver fractions derived from Swiss albino CD1 mice fed 7.5g/kg 2-(3)-tert-butyl-4-hydroxyanisole (BHA; a monofunctional Phase II-inducer) for 3 weeks, show a clear pattern of induction with an approximately 3.5–9.5-fold increase in glutathione S-transferase activity. In vitro DNA binding of the promutagenic agents, [14C]-l,4-dichlorobenzene (DCB) and [14C]-1,4-dibromobenzene (DBB), is mediated by such metabolic liver preparations and showed a significant increase in covalent binding capability. In some instances, enzyme activity was more elevated when compared to that obtained with traditional (Phase I-induced) S9. Together with DNA binding, the genetic response of these chemicals in the diploid D7 strain of Saccharomyces cerevisiae used as a biological test system, revealed the ability of the BHA-derived preparations to activate the promutagenic agents, as exemplified by the significant enhancement of mitotic gene-conversion (up to 5.2-fold for DCB and 3.4-fold for DBB) and reverse point mutation (up to 3.6-fold for DCB and 2.5-fold for DBB) at a 4mM concentration. This novel metabolising biosystem, with enhanced Phase II activity, is recommended together with a traditional S9, for detecting unknown promutagens in genotoxicity studies. The routine use of either oxidative or post-oxidative S9 increases the responsiveness of the test and can contribute to the identification of promutagens not detected when using traditional protocols.

Intrathecal Mafosfamide: A Preclinical Pharmacology and Phase I Trial

2005 ◽  
Vol 23 (7) ◽  
pp. 1555-1563 ◽  
Author(s):  
Susan M. Blaney ◽  
Frank M. Balis ◽  
Stacey Berg ◽  
Carola A.S. Arndt ◽  
Richard Heideman ◽  
...  
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
Phase I Trial ◽  
Neoplastic Meningitis ◽  
In Vitro Cytotoxicity ◽  
Pharmacokinetic Studies ◽  
Preclinical Studies ◽  
Phase Ii Trials ◽  
Cytotoxicity Studies

Purpose Preclinical studies of mafosfamide, a preactivated cyclophosphamide analog, were performed to define a tolerable and potentially active target concentration for intrathecal (IT) administration. A phase I and pharmacokinetic study of IT mafosfamide was performed to determine a dose for subsequent phase II trials. Patients and Methods In vitro cytotoxicity studies were performed in MCF-7, Molt-4, and rhabdomyosarcoma cell lines. Feasibility and pharmacokinetic studies were performed in nonhuman primates. These preclinical studies were followed by a phase I trial in patients with neoplastic meningitis. There were five dose levels ranging from 1 mg to 6.5 mg. Serial CSF samples were obtained for pharmacokinetic studies in a subset of patients with Ommaya reservoirs. Results The cytotoxic target exposure for mafosfamide was 10 μmol/L. Preclinical studies demonstrated that this concentration could be easily achieved in ventricular CSF after intraventricular dosing. In the phase I clinical trial, headache was the dose-limiting toxicity. Headache was ameliorated at 5 mg by prolonging the infusion rate to 20 minutes, but dose-limiting headache occurred at 6.5 mg dose with prolonged infusion. Ventricular CSF mafosfamide concentrations at 5 mg exceeded target cytotoxic concentrations after an intraventricular dose, but lumbar CSF concentrations 2 hours after the dose were less than 10 μmol/L. Therefore, a strategy to alternate dosing between the intralumbar and intraventricular routes was tested. Seven of 30 registrants who were assessable for response had a partial response, and six had stable disease. Conclusion The recommended phase II dose for IT mafosfamide, administered without concomitant analgesia, is 5 mg over 20 minutes.

Effects of Ofloxacin Administration on the Reliability of Urine Glucose Testing

1996 ◽  
Vol 30 (5) ◽  
pp. 469-472
Author(s):  
Tsong-Mei Tsai ◽  
Brian F Shea ◽  
Paul F Souney ◽  
Fred G Volinsky ◽  
Joseph M Scavone ◽  
...  
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
Tertiary Care ◽  
Urine Samples ◽  
Care Hospital ◽  
Open Label ◽  
Urine Glucose ◽  
Glucose Testing

OBJECTIVE: TO study the effects of ofloxacin on the reliability of urine glucose testing. DESIGN: Open-label, nonrandomized. SETTING: A university-affiliated tertiary care hospital, ambulatory clinic. PARTICIPANTS: Ten healthy volunteers (8 men and 2 women) aged 22-39 years. MAIN OUTCOME MEASURES: Phase I (in vitro) involved the addition of selected amounts of ofloxacin to a set of standard 50-mL urine samples prepared to simulate glycosuria. Phase II (in vivo) involved the oral administration of ofloxacin 400 mg to 10 subjects. Urine was collected: (1) immediately predose, (2) pooled 0–4 hours postdose, and (3) pooled 4–8 hours postdose. Known glucose concentrations were then added to these samples. Clinitest and Diastix tests were performed on all samples. The accuracy of these tests in determining glucose concentrations was compared among urine samples taken before and after ofloxacin dosing. RESULTS: None of the ofloxacin concentrations in phase I (0,25,50, 100, 200,400, and 800 μg/mL) influenced these testing methods at the urine glucose concentrations of 0.0%, 0.5%, 1%, and 2%. Likewise, the accuracy of these two tests was unaffected by ofloxacin administration in phase II. CONCLUSIONS: In single-dose administration, ofloxacin does not interfere with Clinitest or Diastix for determining urine glucose concentrations. Supported by a grant from the RW Johnson Pharmaceutical Research Institute. Presented in abstract form at the American College of Clinical Pharmacy 1994 Winter Practice and Research Forum, February 6–9, 1994, San Diego. CA.

Combined effect of genetic polymorphisms in phase I and II biotransformation enzymes on head and neck cancer risk

Head & Neck ◽  
2012 ◽  
Vol 35 (6) ◽  
pp. 858-867 ◽  
Author(s):  
Martin Lacko ◽  
Adri C. Voogd ◽  
Hennie M. J. Roelofs ◽  
Rene H. M. te Morsche ◽  
Michel B. Oude Ophuis ◽  
...  
Keyword(s):  
Head And Neck Cancer ◽  
Cancer Risk ◽  
Phase I ◽  
Head And Neck ◽  
Genetic Polymorphisms ◽  
Neck Cancer ◽  
Combined Effect ◽  
Biotransformation Enzymes ◽  
Phase I And Ii

scholarly journals Ochratoxin A-Induced Hepatotoxicity through Phase I and Phase II Reactions Regulated by AhR in Liver Cells

Toxins ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 377 ◽  
Author(s):  
Hye Soo Shin ◽  
Hyun Jung Lee ◽  
Min Cheol Pyo ◽  
Dojin Ryu ◽  
Kwang-Won Lee
Keyword(s):  
Oxidative Stress ◽  
Phase I ◽  
Ochratoxin A ◽  
Phase Ii ◽  
Glutathione Depletion ◽  
Related Factor ◽  
Aryl Hydrocarbon ◽  
Similar Mode ◽  
Phase I And Ii

Ochratoxin A (OTA) is a widespread mycotoxin produced by several species of the genera Aspergillus and Penicillium. OTA exists in a variety of foods, including rice, oats, and coffee and is hepatotoxic, with a similar mode of action as aflatoxin B1. The precise mechanism of cytotoxicity is not yet known, but oxidative damage is suspected to contribute to its cytotoxic effects. In this study, human hepatocyte HepG2 cells were treated with various concentrations of OTA (5–500 nM) for 48 h. OTA triggered oxidative stress as demonstrated by glutathione depletion and increased reactive oxygen species, malondialdehyde level, and nitric oxide production. Apoptosis was observed with 500 nM OTA treatment. OTA increased both the mRNA and protein expression of phase I and II enzymes. The same results were observed in an in vivo study using ICR mice. Furthermore, the relationship between phase I and II enzymes was demonstrated by the knockdown of the aryl hydrocarbon receptor (AhR) and NF-E2-related factor 2 (Nrf2) with siRNA. Taken together, our results show that OTA induces oxidative stress through the phase I reaction regulated by AhR and induces apoptosis, and that the phase II reaction is activated by Nrf2 in the presence of oxidative stress.

Phase I and II study of high-dose ifosfamide, carboplatin, and etoposide with autologous bone marrow rescue in lymphomas and solid tumors.

1992 ◽  
Vol 10 (11) ◽  
pp. 1712-1722 ◽  
Author(s):  
W H Wilson ◽  
V Jain ◽  
G Bryant ◽  
K H Cowan ◽  
C Carter ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Phase I ◽  
Solid Tumors ◽  
Autologous Bone Marrow ◽  
Maximum Tolerated Dose ◽  
High Dose ◽  
Autologous Bone ◽  
Hodgkin's Lymphomas ◽  
Phase I And Ii

PURPOSE High-dose chemotherapy produces durable disease-free remissions in a minority of patients with resistant lymphomas and solid tumors. In an attempt to improve on the available regimens, ifosfamide, carboplatin, and etoposide (ICE) were selected for a new high-dose regimen because of their favorable spectrum of nonhematopoietic toxicity and evidence of synergy in in vitro systems. PATIENTS AND METHODS Forty-one patients with drug-resistant Hodgkin's and non-Hodgkin's lymphomas, and breast and testicular cancers were entered onto a phase I and II trial of a single course of ICE with autologous bone marrow rescue. Before transplantation, all patients received combination chemotherapy until maximal tumor response was achieved. RESULTS Patients received total doses of ifosfamide from 10 to 18 g/m2, carboplatin from 0.9 to 1.98 g/m2, and etoposide from 0.6 to 1.5 g/m2 administered during a 4-day period, with a maximum-tolerated dose (MTD) of ifosfamide 16 g/m2, carboplatin 1.8 g/m2, and etoposide 1.5 g/m2. The dose-limiting toxicities included irreversible renal, cardiac, and CNS dysfunction. There were three toxic deaths (7%), and all occurred above the MTD. Thirteen patients who were treated at the MTD tolerated the regimen well; reversible renal dysfunction and grade 2 mucositis commonly were observed. Of 23 heavily pretreated patients with persistent disease at the time of transplant, 10 (43%) achieved complete remissions (CRs) and 11 (48%) achieved partial remissions (PRs). Hodgkin's and non-Hodgkin's lymphoma patients who were treated at or below the MTD had a median potential follow-up of 11.9 months, and 12-month progression-free survivals of 62% and 48%, respectively. CONCLUSION High-dose ICE with bone marrow rescue was well tolerated with a high response rate, and should be considered for further testing.

Gas Chromatographic Determination of Poly chlorinated Biphenyls (as Aroclor 1254) in Serum: Collaborative Study

1989 ◽  
Vol 72 (4) ◽  
pp. 649-659
Author(s):  
Virlyn W Burse ◽  
Margaret P Korver ◽  
Larry L Needham ◽  
Chester R Lapeza ◽  
Elizabeth L Chester R ◽  
...  
Keyword(s):  
Phase I ◽  
Silica Gel ◽  
Phase Ii ◽  
Collaborative Study ◽  
Chlorinated Hydrocarbons ◽  
Aroclor 1254 ◽  
Relative Standard

Abstract A gas chromatographic-electron capture detection method for determining the concentration of polychlorinated biphenyls (PCBs) as Aroclor 1254 (AR 1254) in serum was evaluated through a 2-phase collaborative study. In Phase I, each collaborator's lot of Woelm silica gel (70-150 mesh) was evaluated for elution and recovery of AR 1254, which had been added in vitro at 25 ng/mL to a serum extract. In Phase II, each collaborator analyzed a series of bovine serum samples that contained the following: (1) in vitro-spiked AR 1254; (2) in vivo AR 1254 and 8 in vitro-spiked chlorinated hydrocarbons; (3) in vivo AR 1254 only; (4) 8 in vitro-spiked chlorinated hydrocarbons only; and (5) neither AR 1254 nor chlorinated hydrocarbons above the detection limit of the method. In Phase I, the average recovery of AR 1254 from silica gel for the 6 collaborators was 87.9 ± 15.44% (mean ± 1 SD; N = 18; range = 52.3-105.8%). In Phase II, the analysis of in vitro spikes of AR 1254 in serum at 8.58,16.8, 41.8, and 84.3 ppb gave mean (X) interlaboratory recoveries of 89.0, 83.3, 79.4, and 76.9%, respectively, with within-laboratory (repeatability) relative standard deviations (RSDr) of 18.8, 20.5, 10.2, and 14.1%, respectively, and among-laboratory (reproducibility) relative standard deviations (RSDR) of 21.5, 21.1, 14.6, and 20.8%, respectively. The determination of in vivo AR 1254 in samples containing approximately 10, 25, 50, and 100 ng/mL of AR 1254 resulted in interlaboratory means of 10,22,39, and 79 ng/mL, respectively, with RSDr = 6.7,9.7,6.4, and 5.8%, respectively, and RSDR = 20.6,16.0, 10.9, and 10.3%, respectively. The precision of the method for incurred AR 1254 showed a maximum RSDr of less than 10% and a maximum RSDR of less than 21% for a concentration range of 10-100 ng/mL. The accuracy of the method as demonstrated by the mean recovery of in vitro-spiked AR 1254 over a concentration range of 8.58-84.3 ng/mL was 82.2%. The method has been approved interim official first action.

Combination of Sorafenib, Idarubicin, and Cytarabine Has a High Response Rate in Patients with Newly Diagnosed Acute Myeloid Leukemia (AML) Younger Than 65 Years

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 768-768 ◽  
Author(s):  
Farhad Ravandi ◽  
Jorge Cortes ◽  
Stefan Faderl ◽  
Guillermo Garcia-Manero ◽  
Susan O’Brien ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Phase I ◽  
Cell Lines ◽  
Phase Ii ◽  
Kinase Inhibitor ◽  
Single Agent ◽  
High Response Rate ◽  
Clinical Activity ◽  
Mutation Burden

Abstract Background: Sorafenib is an orally active multi-kinase inhibitor with potent activity against the Raf/ERK/MEK pathway, VEGFR, PDGFR-β, and c-KIT. In vitro, it has growth-inhibitory effects in several AML cell lines with or without constitutive activation of ERK signaling. Sorafenib selectively induces cell growth arrest and apoptosis in FLT3-mutant human AML cell lines at nM concentrations. In a phase I study of single agent sorafenib in patients (pts) with AML escalating doses were well tolerated with no myelosuppression and with significant clinical activity predominantly (but not exclusively) in FLT3 mutated pts. Methods: This study was conducted to determine the tolerability and efficacy of combination of sorafenib with cytarabine 1.5 g/m2 iv over 24 hours daily × 4 (× 3 for pts over 60) and idarubicin 12 mg/m2 iv daily × 3. In the phase I portion of study, pts with relapsed AML were treated with escalating doses of sorafenib po (400 mg qod, 400 mg daily and 400 mg bid) for 7 days during induction, and 400 mg bid was established as a safe dose for phase II evaluation. Pts achieving CR receive up to 5 courses of consolidation with idarubicin 8 mg/m2 iv daily × 2 and cytarabine 0.75 g/m2 iv daily × 3 in addition to continuous sorafenib 400 mg po bid for up to 28 days per cycle. Maintenance with sorafenib 400 mg bid would continue for up to a year after consolidation. Results: Ten pts (median age 34 years, range 21–58) with relapsed AML (median prior therapy 2, range 1–6) were treated on the phase I portion. Seven had FLT3-ITD mutation (5 with high mutation burden, 2 with low), and 3 were negative. Four achieved CR, and 6 failed. In the phase II portion, 30 pts (including 8 with FLT3-ITD and 2 with FLT3-TKD) have been treated. Median age is 53 years (range 18 – 65) Cytogenetics were diploid in 13, +8 in 3, −5/−7 in 3, t(9;11) in 1, miscellaneous in 6, and unavailable in 4. The median presentation WBC was 4.6 × 109/L (range 1.5 –122.7 × 109/L). FLT3 mutation burden was low in blasts from 4 pts, and high in 6). Five pts were FLT3-ITD+/NPM1-. Among 25 evaluable pts, 22 (88%) have achieved CR (n=19), or CRi (n=3); 1 achieved PR, 1 died at induction from pneumonia, 1 was resistant; 5 pts are too early. The regimen is well tolerated and grade 3 adverse events thought to be possibly related to the study combination have included elevation of transaminases (3), hyperbilirubinemia (4), small bowel obstruction (1), diarrhea (2), rash (2), pericarditis (1), elevated creatinine (1), and atrial fibrillation (1). Median follow-up is 8 weeks (range, 1 – 28) with the probability of survival at 6 months of 87%; 2 pts have relapsed with CR durations of 2 and 3 months. Samples from 8 pts were studied prior to and 24–48 hours post sorafenib administration, and prior to chemotherapy. In six pts (75%), sorafenib alone induced apoptosis in peripheral blood blasts and in CD33/CD34 positive leukemia progenitor cells as determined by flow cytometry. Expression of phospho-ERK (pERK) was detectable by flow cytometry in 5 out of 7 samples tested at baseline; 24-hour exposure to sorafenib resulted in >50% downregulation of pERK in 3 of the 5 samples. Plasma inhibitory assay was performed using day 7 samples from 10 pts; mutant FLT3 was suppressed by all samples with 5-fold more potent suppression against mutant versus wildtype FLT3. Conclusions: Combination of sorafenib with idarubicin and cytarabine is safe and has a high CR rate in frontline therapy of younger pts with AML. Correlative studies confirm potent activity of sorafenib against ERK and FLT3 signaling.

Novel organic arsenic molecule darinaparsin: Development of IV and oral forms

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. 8501-8501 ◽  
Author(s):  
I. Lossos ◽  
M. D. Craig ◽  
M. S. Tallman ◽  
R. V. Boccia ◽  
P. R. Conkling ◽  
...  
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
Phase Ii Study ◽  
Complete Response ◽  
Median Number ◽  
Two Phase ◽  
Phase I Studies ◽  
Advanced Malignancies

8501 Background: Darinaparsin (ZIO-101) is a novel organic arsenical active against diverse cancers in vitro, and in vivo. Darinaparsin i.v. activity in lymphoma is being evaluated in a phase II study. Darinaparsin is orally bioavailable; the oral form is being investigated in two phase I studies in patients with advanced malignancies. Methods: Phase II trial is being conducted in patients diagnosed with advanced lymphomas who had ≥ 1 prior therapy. Patients receive 300 mg/m2/day of darinaparsin i.v. for 5 consecutive days every 28 days. Efficacy and safety are evaluated by standard criteria. Phase I oral dose escalation studies are being conducted in patients with advanced malignancies and explore safety, MTD, DLTs and preliminary efficacy of continuous and intermittent dosing schedules. Starting continuous dose is 100 mg BID for 3 weeks with 1 week rest, starting intermittent dose is 300 mg twice weekly for 3 weeks followed by 1 week rest. Results: The phase II study has accrued 28 lymphoma patients (21 non-Hodgkin's, 7 Hodgkin's); median age at baseline 61 years, ECOG ≤2, median number of prior therapies 3. Seventeen subjects have received at least 2 cycles of darinaparsin and are evaluable for efficacy. Of these, 1 subject (PTCL) has achieved a complete response, 3 - partial responses (2 marginal zone, 1 Hodgkin's), and 4 stable disease (2 PTCL, 1 DLBCL, 1 Hodgkin's). A total of 63 cycles of darinaparsin have been administered to subjects with lymphoma. No Gr. 3 or higher drug-related AEs were reported. Two SAEs were considered possibly drug-related (fall; neutropenic fever). Phase I studies accrued 35 patients; median age at baseline 58 years, ECOG ≤2, median number of prior therapies 3. Predominant tumor types include: colorectal (17), pancreatic (3), NHL (3). Current darinaparsin dose levels: continuous 200 mg BID, 2× weekly 900 mg. Of 18 patients evaluable for efficacy, 10 demonstrate SD ≥ 3 cycles. Oral darinaparsin bioavailability is 58%. Drug-related AEs include nausea/vomiting, fatigue, decreased appetite/anorexia. Conclusions: Darinaparsin is active in heavily pretreated patients with advanced lymphoma and has been very well tolerated. Oral darinaparsin is also well tolerated, and shows early activity. [Table: see text]

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