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1.
Obes Surg ; 34(1): 286-289, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38012508

ABSTRACT

OBJECTIVE: The effectiveness of liraglutide 3.0 mg (Saxenda) therapy to induce weight loss among obese patients prior to bariatric surgery remains uncertain. METHODS: Clinical data was retrospectively obtained from patients with prediabetes (HbA1c 42-47 mmol/mol) and selected patients on the waiting list for bariatric surgery at the Royal Derby Hospital. Clinical data was collected retrospectively at 6, 12, 26 and 52 week intervals. The outcomes included mean weight change, proportion of patients achieving ≥ 5% and ≥ 10% weight loss and achieving HbA1c reduction to normal range values. RESULTS: Fifty patients (mean age of 46.2 ± 10.5 years; 76% female and 94% had Class III obesity) who completed 52 and/or 26 weeks of treatment were included. Liraglutide 3.0 mg produced a consistent and statistically significant reduction in weight (kg), BMI (kg/m2) and HbA1c (mmol/mol) across all four time intervals. Average ± SD reduction for weight, BMI and HbA1c respectively at 26 weeks were: -10.9 ± 9.1 (P < 0.01), -3.67 ± 3.5 (P < 0.01), -4.7 IQR 4.95 (P < 0.001), and at 52 weeks were: -14 ± 9.2 kg (P < 0.001), -4.64 ± 4.0 (P < 0.001 and -5.5 IQR 4 (P = 0.009). 85.7% and 33.3% of patients achieved ≥ 5% and 10% weight loss target respectively at 52 weeks. 92.3% and 72.2% achieved remission of pre-diabetes by 6 and 12 months respectively. Liraglutide 3.0 mg was well-tolerated with only 10% discontinuing medication due to tolerability issues. CONCLUSION: Liraglutide 3.0 mg, with lifestyle management, reduced weight and improved glycaemic control. These results support liraglutide's application in certain high-risk populations, including patients waiting for bariatric surgical intervention.


Subject(s)
Bariatric Surgery , Diabetes Mellitus, Type 2 , Obesity, Morbid , Prediabetic State , Humans , Female , Adult , Middle Aged , Male , Liraglutide/therapeutic use , Liraglutide/pharmacology , Hypoglycemic Agents/therapeutic use , Prediabetic State/drug therapy , Glycated Hemoglobin , Retrospective Studies , Obesity, Morbid/surgery , Obesity/drug therapy , Weight Loss , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/surgery , Treatment Outcome
2.
Disaster Med Public Health Prep ; 17: e550, 2023 Dec 04.
Article in English | MEDLINE | ID: mdl-38044835

ABSTRACT

OBJECTIVE: Evidence of myelosuppression has been negatively correlated with patient outcomes following cases of high dose sulfur mustard (SM) exposure. These hematologic complications can negatively impact overall immune function and increase the risk of infection and life-threatening septicemia. Currently, there are no approved medical treatments for the myelosuppressive effects of SM exposure. METHODS: Leveraging a recently developed rodent model of SM-induced hematologic toxicity, post-exposure efficacy testing of the granulocyte colony-stimulating factor drug Neupogen® was performed in rats intravenously challenged with SM. Before efficacy testing, pharmacokinetic/pharmacodynamic analyses were performed in naïve rats to identify the apparent human equivalent dose of Neupogen® for efficacy evaluation. RESULTS: When administered 1 d after SM-exposure, daily subcutaneous Neupogen® treatment did not prevent the delayed onset of hematologic toxicity but significantly accelerated recovery from neutropenia. Compared with SM controls, Neupogen®-treated animals recovered body weight faster, resolved toxic clinical signs more rapidly, and did not display transient febrility at time points generally concurrent with marked pancytopenia. CONCLUSIONS: Collectively, this work corroborates the results of a previous pilot large animal study, validates the utility of a rodent screening model, and provides further evidence for the potential clinical utility of Neupogen® as an adjunct treatment following SM exposure.


Subject(s)
Mustard Gas , Humans , Rats , Animals , Filgrastim/pharmacology , Filgrastim/therapeutic use , Mustard Gas/toxicity , Neutrophils , Rodentia , Granulocyte Colony-Stimulating Factor/pharmacology , Granulocyte Colony-Stimulating Factor/therapeutic use
4.
R I Med J (2013) ; 105(4): 57-62, 2022 May 02.
Article in English | MEDLINE | ID: mdl-35476740

ABSTRACT

BACKGROUND: The patient-centered medical home (PCMH) is an ideal primary care model for patients across the lifespan. Family Medicine (FM) practice and training often address adults more than children/adolescents. Few studies describe the efficacy of education programs seeking to enhance PCMH-based care of children/adolescents. METHODS: At the Brown FM Residency in Pawtucket, Rhode Island (RI), from 2015-2020, we aimed to enhance care of children/adolescents through a HRSA-funded program that enhanced PCMH-based care for children/adolescents and related resident education. Our mixed- methods evaluation assessed learner experiences. Vaccination data assessed patient impact. RESULTS: 119/155 (77%) residents completed surveys over four years and learning and performance improved, especially in PCMH principles and behavorial health (BH) competencies. Vaccination rates improved. Qualitative interviews supported quantitative results. CONCLUSIONS: Enhancing care for children/adolescents within a FM residency clinic requires a multi-pronged approach. This initiative improved children/adolescents' care and increased residents' learning and performance.


Subject(s)
Internship and Residency , Adolescent , Adult , Child , Clinical Competence , Curriculum , Family Practice/education , Humans , Quality Improvement
5.
Proc Natl Acad Sci U S A ; 119(11): e2121609119, 2022 03 15.
Article in English | MEDLINE | ID: mdl-35259016

ABSTRACT

SignificanceNeurodegenerative diseases are poorly understood and difficult to treat. One common hallmark is lysosomal dysfunction leading to the accumulation of aggregates and other undegradable materials, which cause damage to brain resident cells. Lysosomes are acidic organelles responsible for breaking down biomolecules and recycling their constitutive parts. In this work, we find that the antiinflammatory and neuroprotective compound, discovered via a phenotypic screen, imparts its beneficial effects by targeting the lysosome and restoring its function. This is established using a genome-wide CRISPRi target identification screen and then confirmed using a variety of lysosome-targeted studies. The resulting small molecule from this study represents a potential treatment for neurodegenerative diseases as well as a research tool for the study of lysosomes in disease.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Lysosomes/drug effects , Neurodegenerative Diseases/metabolism , Animals , Anti-Inflammatory Agents/chemistry , Biomarkers , Brain/drug effects , Brain/metabolism , Disease Models, Animal , Disease Susceptibility , Drug Development , Gene Expression Profiling , Humans , Mice , Neurodegenerative Diseases/drug therapy , Neurodegenerative Diseases/etiology , Neurodegenerative Diseases/pathology , Neurons/drug effects , Neurons/metabolism , Smad Proteins/agonists
7.
Article in English | MEDLINE | ID: mdl-35158319

ABSTRACT

Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) has become a mainstay analytical technique in pharmaceutical research and development and clinical diagnosis due to several advantages including excellent selectivity, specificity, and high sensitivity. LC-MS/MS has become the method of choice for steroids analysis due to its fast analytical time and improved specificity yet has a challenge in the separation and measurement of isomers with the same product ions. Here we describe a high-sensitivity LC/LC-MS/MS method that combines chiral chromatography and reverse-phase chromatography (LC/LC) along with MS/MS to rapidly separate and quantify steroid isomers of 11ß-methyl-19-nortestosterone (11ß-MNT) and endogenous testosterone in serum.

8.
Anal Bioanal Chem ; 414(5): 1933-1947, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34997251

ABSTRACT

Liquid chromatography (LC) coupled with tandem mass spectrometry (MS/MS) provides a simple and efficient means for the measurement of analytes in biological matrices with high selectivity and specificity. LC-MS/MS plays an important role in the pharmaceutical industry and biomedical research, but it requires analytes to be in an ionized form in order to be detected. This can pose a challenge for large molecules such as proteins and peptides, because they can exist in multiple charged forms, and this will reduce the total analyte signal by distributing it into multiple ion peaks with a different number of charges in a mass spectrum. In conventional LC-MS/MS analysis of such macromolecules, one charged form is selected as the precursor ion which is then fragmented by collision-induced dissociation (CID) in MS/MS to generate product ions, a process referred to as multiple-reaction monitoring (MRM). The MRM method minimizes interference from endogenous molecules within biological matrices that share the same molecular weight of the precursor ion, but at the expense of signal intensity as compared to precursor ion intensity. We describe here an approach to boost detection sensitivity and expand dynamic range in the quantitation of large molecules while maintaining analytical specificity using summation of MRM (SMRM) transitions and LC separation technique. Protein image from PDB-101 (PDB101.rscb.org).


Subject(s)
Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods , Animals , Feasibility Studies , Limit of Detection , Rats , Rats, Sprague-Dawley
9.
J Pharmacol Exp Ther ; 380(3): 162-170, 2022 03.
Article in English | MEDLINE | ID: mdl-35058349

ABSTRACT

The novel wound-healing biologic EPICERTIN, a recombinant analog of cholera toxin B subunit, is in early development for the management of ulcerative colitis. This study established for the first time the pharmacokinetics (PK), bioavailability (BA), and acute safety of EPICERTIN in healthy and dextran sodium sulfate-induced colitic mice and healthy rats. For PK and BA assessments, single administrations of various concentrations of EPICERTIN were given intravenously or intrarectally to healthy and colitic C57BL/6 mice and to healthy Sprague-Dawley rats. After intravenous administration to healthy animals, the drug's plasma half-life (t 1/2) for males and females was 0.26 and 0.3 hours in mice and 19.4 and 14.5 hours in rats, respectively. After intrarectal administration, drug was detected at very low levels in only four samples of mouse plasma, with no correlation to colon epithelial integrity. No drug was detected in rat plasma. A single intrarectal dose of 0.1 µM (0.6 µg/mouse) EPICERTIN significantly facilitated the healing of damaged colonic epithelium as determined by disease activity index and histopathological scoring, whereas 10-fold higher or lower concentrations showed no effect. For acute toxicity evaluation, healthy rats were given a single intrarectal administration of various doses of EPICERTIN with sacrifice on Day 8, recording body weight, morbidity, mortality, clinical pathology, and gross necropsy observations. There were no drug-related effects of toxicological significance. The no observed adverse effect level (intrarectal) in rats was determined to be 5 µM (307 µg/animal, or 5.2 µg drug/cm2 of colorectal surface area), which is 14 times the anticipated intrarectally delivered clinical dose. SIGNIFICANCE STATEMENT: EPICERTIN is a candidate wound-healing biologic for the management of ulcerative colitis. This study determined for the first time the intravenous and intrarectal pharmacokinetics and bioavailability of the drug in healthy and colitic mice and healthy rats, and its acute safety in a dose-escalation study in rats. An initial therapeutic dose in colitic mice was also established. EPICERTIN delivered intrarectally was minimally absorbed systemically, was well tolerated, and induced epithelial wound healing topically at a low dose.


Subject(s)
Biological Products , Colitis, Ulcerative , Wound Healing , Administration, Topical , Animals , Biological Products/administration & dosage , Biological Products/adverse effects , Biological Products/pharmacokinetics , Colitis, Ulcerative/drug therapy , Disease Models, Animal , Female , Male , Mice , Mice, Inbred C57BL , Rats , Rats, Sprague-Dawley , Rodentia , Wound Healing/drug effects
10.
Early Hum Dev ; 166: 105542, 2022 03.
Article in English | MEDLINE | ID: mdl-35085882

ABSTRACT

BACKGROUND: Tremendous medical advancements over the last several decades have supported the survival of younger and sicker newborns. Substantial quantitative research exists about health and developmental outcomes following preterm birth, however, limited published literature has explored what this experience means to the survivors. AIM: The purpose was to describe, interpret and understand how adults born preterm perceive prematurity to have affected their lives. STUDY DESIGN: Qualitative thematic analysis. METHODS: Semi-structured interviews were conducted with 33 adults born preterm from the RHODE Study, a longitudinal preterm birth cohort. A cross-section of participants with high and low early life medical and environmental risk was interviewed. Data were analyzed using a constructionist method of latent theme analysis. RESULTS: From the data, 3 themes were identified: 1) My parents call me their miracle, 2) It's not a big deal, I'm the same as everyone else, 3) I've overcome a lot. Themes represent a continuum of experience, from positive to neutral to negative. Common life experiences of family, education, friends, and health are subthemes that help to illuminate how participants assign meaning to their prematurity. Meaning was linked to how typical or not participants perceive their health, learning and friends compared to peers. CONCLUSION: Perceptions about prematurity and adversity are influenced by the ways parents and families represent prematurity in shared stories and actions. These findings should inform future research with adult survivors of prematurity. Participants identified ongoing need for support and advocacy, particularly from healthcare and education communities.


Subject(s)
Infant, Premature, Diseases , Premature Birth , Adult , Humans , Infant, Low Birth Weight , Infant, Newborn , Parents , Premature Birth/epidemiology
11.
Lymphat Res Biol ; 19(5): 431-441, 2021 10.
Article in English | MEDLINE | ID: mdl-34672794

ABSTRACT

Background: Chronic edema (CO) is a complex condition, arising from different factors, including immobility and obesity. Edema and obesity can have a significant impact on quality of life of patients and their families. Understanding how to manage edema in obese patients is an increasing challenge for both patients and clinicians. As effective treatment options are limited for this population, it is more cost-effective for patients to lose weight before starting treatment. When patients cannot maintain weight loss, one option is to have bariatric surgery. This study was part of LIMPRINT: Lymphedema IMpact and PRevalence INTernational, a study with the aim of identifying the prevalence and impact of CO in different countries and health care settings. Study Purpose: To evaluate the prevalence and impact of CO among patients in a United Kingdom bariatric surgical service. Methods and Results: The gold standard pitting test assessed the presence of edema. General (EuroQOL-5 Dimensions [EQ-5D], RAND 36-Item Short Form Health Survey, Version 1.0 [SF-36], Generalized Anxiety Disorder 7-Item Scale [GAD-7] and Patient Health Questionnaire-9 [PHQ-9]), and edema-specific (Lymphedema Quality of Life [LYMQOL]) quality-of-life questionnaires were used to evaluate impact of edema. The prevalence of edema was 52.1% (25 of 48 participants had edema), potentially linked to obesity, immobility, and medications. Most participants had International Society of Lymphology (ISL) Stage I edema. There were no statistically significant differences between the quality of life of participants with and without edema. However, comparing SF-36 results and normative population data indicated that quality of life was much lower than those in the normative population. Conclusions: This study highlights the high prevalence of edema and low quality of life of this bariatric population. ClinicalTrials.gov ID: NCT03154593.


Subject(s)
Bariatrics , Quality of Life , Chronic Disease , Diagnosis, Differential , Edema/diagnosis , Edema/epidemiology , Edema/etiology , Humans , Lymphatic System , Prevalence , Surveys and Questionnaires
12.
Pharm Dev Technol ; 25(5): 625-639, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32031478

ABSTRACT

To improve the solubility and oral bioavailability of a novel antimalarial agent ELQ-331(a prodrug of ELQ-300), spray-dried dispersions (SDD) and a self-emulsifying drug delivery system (SEDDS) were developed. SDD were prepared with polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (Soluplus®) polymer carrier and Aeroperl® 300 Pharma and characterized by differential scanning calorimetry, powder X-ray diffraction. For SEDDS, solubility in oils, surfactants, and co-surfactants was determined and ternary phase diagram was constructed to show self-emulsifying area. SEDDS were characterized for spontaneous emulsification and droplet size distribution. The amorphous ELQ-331 SDD improved the solubility to 10× in fast-state simulated intestinal fluid and addition of sodium lauryl sulphate externally to SDDs further improved the solubility to ∼28.5× versus non-formulated drug. SEDDS had good self-emulsifying characteristics with small emulsion droplet sizes and narrow particle distribution. Oral pharmacokinetic studies for SDD and SEDDS formulations were performed in rats. The ELQ-331 rapidly converted to ELQ-300 soon after oral administration in rats. Exposure levels of ELQ-300 were about 1.4-fold higher (based on AUC) in SEDDS than SDD formulations. Poorly soluble drugs like ELQ-331 can be formulated using SDD or SEDDS to improve solubility and oral bioavailability.


Subject(s)
Antimalarials/chemistry , Drug Compounding/methods , Drug Delivery Systems/methods , Prodrugs/chemistry , Quinolones/chemistry , Administration, Oral , Animals , Antimalarials/administration & dosage , Antimalarials/blood , Biological Availability , Drug Stability , Emulsions , Excipients/chemistry , Male , Molecular Structure , Polyethylene Glycols/chemistry , Polyvinyls/chemistry , Prodrugs/administration & dosage , Quinolones/administration & dosage , Quinolones/blood , Rats, Sprague-Dawley , Solubility
13.
Mol Cancer Ther ; 19(3): 858-867, 2020 03.
Article in English | MEDLINE | ID: mdl-31941722

ABSTRACT

Prodrugs are harmless until activated by a bacterial or viral gene product; they constitute the basis of gene-delivered prodrug therapies called GDEPT, which can kill tumors without major side effects. Previously, we utilized the prodrug CNOB (C16H7CIN2O4; not clinically tested) and enzyme HChrR6 in GDEPT to generate the drug MCHB (C16H9CIN2O2) in tumors. Extracellular vesicles (EVs) were used for directed gene delivery and HChrR6 mRNA as gene. Here, the clinical transfer of this approach is enhanced by: (i) use of CB1954 (tretazicar) for which safe human dose is established; HChrR6 can activate this prodrug. (ii) EVs delivered in vitro transcribed (IVT) HChrR6 mRNA, eliminating the potentially harmful plasmid transfection of EV producer cells we utilized previously; this has not been done before. IVT mRNA loading of EVs required several steps. Naked mRNA being unstable, we ensured its prodrug activating functionality at each step. This was not possible using tretazicar itself; we relied instead on HChrR6's ability to convert CNOB into MCHB, whose fluorescence is easily visualizable. HChrR6 mRNA-translated product's ability to generate fluorescence from CNOB vicariously indicated its competence for tretazicar activation. (iii) Systemic IVT mRNA-loaded EVs displaying an anti-HER2 single-chain variable fragment ("IVT EXO-DEPTs") and tretazicar caused growth arrest of human HER2+ breast cancer xenografts in athymic mice. As this occurred without injury to other tissues, absence of off-target mRNA delivery is strongly indicated. Many cancer sites are not amenable for direct gene injection, but current GDEPTs require this. In circumventing this need, a major advance in GDEPT applicability has been accomplished.


Subject(s)
Bacterial Proteins/genetics , Breast Neoplasms/therapy , Extracellular Vesicles/metabolism , Gene Transfer Techniques , Genetic Therapy , Prodrugs/pharmacology , RNA, Messenger/administration & dosage , Animals , Apoptosis , Bacterial Proteins/metabolism , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Cell Proliferation , Extracellular Vesicles/genetics , Female , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptor, ErbB-2/metabolism , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
14.
Int J Radiat Biol ; 96(1): 145-154, 2020 01.
Article in English | MEDLINE | ID: mdl-31021662

ABSTRACT

Purpose: Rapid depletion of white blood cells, platelets, and reticulocytes are hallmarks of hematopoietic injury of acute radiation syndrome (H-ARS) and, if left untreated, can lead to severe health consequences including death. While the granulocyte colony stimulating factors (G-CSF) filgrastim (Neupogen®), pegfilgrastim (Neulasta®), and sargramostim (Leukine®) are approved to increase survival in patients exposed to a myelosuppressive dose of radiation, no medical countermeasure is currently available for treatment of the thrombocytopenia that also results following radiation exposure. Romiplostim (Nplate®), a thrombopoietin receptor agonist, is the first FDA-approved thrombopoiesis-stimulating protein for the treatment of low platelet (PLT) counts in adults with chronic immune thrombocytopenia. Herein, we present the results of an analysis in mice of romiplostim as a medical countermeasure to improve survival and PLT recovery following acute radiation.Materials and methods: Male and female C57BL/6J mice (11 - 12 weeks of age, n = 21/sex/group) were total body irradiated (TBI) with 6.8 Gy X-rays that reduces 30-day survival to 30% (LD70/30). Vehicle, romiplostim, and/or pegfilgrastim were administered subcutaneously beginning 24 h after TBI for 1-5 days. Evaluation parameters included 30-day survival, pharmacokinetics, and hematology.Results: Full or maximal efficacy with an ∼40% increase in survival was achieved after a single 30 µg/kg dose of romiplostim. No further survival benefit was seen with higher (100 µg/kg) or more frequent dosing (3 or 5 once daily doses at 30 µg/kg) of romiplostim or combined treatment with pegfilgrastim. Pharmacodynamic analysis revealed that the platelet nadir was not as low and recovery was faster in the irradiated mice treated with romiplostim when compared with irradiated control animals (Day 8 versus 10 nadir; Day 22 versus 29 recovery to near baseline). Platelet volume also increased more rapidly after romiplostim injection. Kinetic profiles of other hematology parameters were similar between TBI romiplostim-treated and control mice. Peak serum levels of romiplostim in TBI mice occurred 4 - 24 h (Tmax) after injection with a t1/2 of ∼24 h. Cmax values were at ∼6 ng/ml after 30 µg/kg ± TBI and ∼200 ng/ml after 300 µg/kg. A 10-fold higher romiplostim dose increased the AUClast values by ∼35-fold.Conclusion: A single injection of romiplostim administered 24 h after TBI is a promising radiation medical countermeasure that dramatically increased survival, with or without pegfilgrastim, and hastened PLT recovery in mice.


Subject(s)
Blood Platelets/drug effects , Blood Platelets/radiation effects , Medical Countermeasures , Recombinant Fusion Proteins/pharmacology , Thrombopoietin/pharmacology , Animals , Blood Platelets/cytology , Dose-Response Relationship, Drug , Drug Interactions , Female , Filgrastim/pharmacology , Male , Mice , Mice, Inbred C57BL , Platelet Count , Polyethylene Glycols/pharmacology , Receptors, Fc , Recombinant Fusion Proteins/pharmacokinetics , Survival Analysis , Thrombopoietin/pharmacokinetics , X-Rays/adverse effects
15.
Sci Rep ; 9(1): 20199, 2019 12 27.
Article in English | MEDLINE | ID: mdl-31882748

ABSTRACT

During the Ebola virus disease (EVD) epidemic in Western Africa (2013‒2016), antimalarial treatment was administered to EVD patients due to the high coexisting malaria burden in accordance with World Health Organization guidelines. In an Ebola treatment center in Liberia, EVD patients receiving the combination antimalarial artesunate-amodiaquine had a lower risk of death compared to those treated with artemether-lumefantrine. As artemether and artesunate are derivatives of artemisinin, the beneficial anti-Ebola virus (EBOV) effect observed could possibly be attributed to the change from lumefantrine to amodiaquine. Amodiaquine is a widely used antimalarial in the countries that experience outbreaks of EVD and, therefore, holds promise as an approved drug that could be repurposed for treating EBOV infections. We investigated the potential anti-EBOV effect of amodiaquine in a well-characterized nonhuman primate model of EVD. Using a similar 3-day antimalarial dosing strategy as for human patients, plasma concentrations of amodiaquine in healthy animals were similar to those found in humans. However, the treatment regimen did not result in a survival benefit or decrease of disease signs in EBOV-infected animals. While amodiaquine on its own failed to demonstrate efficacy, we cannot exclude potential therapeutic value of amodiaquine when used in combination with artesunate or another antiviral.


Subject(s)
Amodiaquine/therapeutic use , Antiviral Agents/therapeutic use , Artemisinins/therapeutic use , Hemorrhagic Fever, Ebola/drug therapy , Animals , Disease Models, Animal , Drug Combinations , Female , Macaca mulatta , Male
16.
Toxicol Sci ; 169(2): 465-474, 2019 06 01.
Article in English | MEDLINE | ID: mdl-30835286

ABSTRACT

Organophosphate (OP) anticholinesterases cause excess acetylcholine leading to seizures which, if prolonged, result in neuronal damage in the rodent brain. Novel substituted phenoxyalkyl pyridinium oximes have previously shown evidence of penetrating the rat blood-brain barrier (BBB) in in vivo tests with a sarin surrogate (nitrophenyl isopropyl methylphosphonate, NIMP) or the active metabolite of the insecticide parathion, paraoxon (PXN), by reducing the time to cessation of seizure-like behaviors and accumulation of glial fibrillary acidic protein, whereas 2-PAM did not. The neuroprotective ability of our lead oximes (15, 20, and 55) was tested using NeuN, Nissl, and Fluoro-Jade B staining in the rat hippocampus. Following lethal-level subcutaneous challenge with NIMP or PXN, rats were intramuscularly administered a novel oxime or 2-PAM plus atropine and euthanized at 4 days. There were statistically significant increases in the median damage scores of the NeuN-stained NIMP, NIMP/2-PAM, and NIMP/Oxime 15 groups compared with the control whereas the scores of the NIMP/Oxime 20 and NIMP/Oxime 55 were not significantly different from the control. The same pattern of statistical significance was observed with PXN. Nissl staining provided a similar pattern, but without statistical differences. Fluoro-Jade B indicated neuroprotection from PXN with novel oximes but not with 2-PAM. The longer blood residence times of Oximes 20 and 55 compared with Oxime 15 might have contributed to their greater efficacy. These results suggest that novel oximes 20 and 55 were able to penetrate the BBB and attenuate neuronal damage after NIMP and PXN exposure, indicating potential broad-spectrum usefulness.


Subject(s)
Blood-Brain Barrier , Cholinesterase Reactivators/pharmacology , Hippocampus/drug effects , Organophosphates/toxicity , Oximes/pharmacology , Animals , Male , Neuroprotective Agents/pharmacology , Oximes/pharmacokinetics , Rats , Rats, Sprague-Dawley
17.
Chemistry ; 25(16): 4100-4114, 2019 Mar 15.
Article in English | MEDLINE | ID: mdl-30458057

ABSTRACT

Acetylcholinesterase (AChE), an enzyme that degrades the neurotransmitter acetylcholine, when covalently inhibited by organophosphorus compounds (OPs), such as nerve agents and pesticides, can be reactivated by oximes. However, tabun remains among the most dangerous nerve agents due to the low reactivation efficacy of standard pyridinium aldoxime antidotes. Therefore, finding an optimal reactivator for prophylaxis against tabun toxicity and for post-exposure treatment is a continued challenge. In this study, we analyzed the reactivation potency of 111 novel nucleophilic oximes mostly synthesized using the CuAAC triazole ligation between alkyne and azide building blocks. We identified several oximes with significantly improved in vitro reactivating potential for tabun-inhibited human AChE, and in vivo antidotal efficacies in tabun-exposed mice. Our findings offer a significantly improved platform for further development of antidotes and scavengers directed against tabun and related phosphoramidate exposures, such as the Novichok compounds.


Subject(s)
Acetylcholinesterase/drug effects , Organophosphates/toxicity , Oximes/pharmacokinetics , Triazoles/chemistry , Alkynes/chemistry , Animals , Antibiotic Prophylaxis/methods , Antidotes/metabolism , Azides/chemistry , Catalysis , Copper/chemistry , Female , Kinetics , Mice , Molecular Structure , Organophosphates/chemical synthesis , Organophosphorus Compounds/metabolism , Oximes/administration & dosage , Oximes/adverse effects
18.
J Pharmacol Exp Ther ; 367(2): 363-372, 2018 11.
Article in English | MEDLINE | ID: mdl-30190337

ABSTRACT

In the development of antidotal therapy for treatment of organophosphate exposure from pesticides used in agriculture and nerve agents insidiously employed in terrorism, the alkylpyridinium aldoximes have received primary attention since their early development by I. B. Wilson in the 1950s. Yet these agents, by virtue of their quaternary structure, are limited in rates of crossing the blood-brain barrier, and they require administration parenterally to achieve full distribution in the body. Oximes lacking cationic charges or presenting a tertiary amine have been considered as alternatives. Herein, we examine the pharmacokinetic properties of a lead ionizable, zwitterionic hydroxyiminoacetamido alkylamine in mice to develop a framework for studying these agents in vivo and generate sufficient data for their consideration as appropriate antidotes for humans. Consequently, in vitro and in vivo efficacies of immediate structural congeners were explored as leads or backups for animal studies. We compared oral and parenteral dosing, and we developed an intramuscular loading and oral maintenance dosing scheme in mice. Steady-state plasma and brain levels of the antidote were achieved with sequential administrations out to 10 hours, with brain levels exceeding plasma levels shortly after administration. Moreover, the zwitterionic oxime showed substantial protection after gavage, whereas the classic methylpyridinium aldoxime (2-pyridinealdoxime methiodide) was without evident protection. Although further studies in other animal species are necessary, ionizing zwitterionic aldoximes present viable alternatives to existing antidotes for prophylaxis and treatment of large numbers of individuals in terrorist-led events with nerve agent organophosphates, such as sarin, and in organophosphate pesticide exposure.


Subject(s)
Antidotes/pharmacology , Antidotes/pharmacokinetics , Organophosphate Poisoning/drug therapy , Organophosphates/adverse effects , Administration, Oral , Animals , Brain/drug effects , Female , Lead/adverse effects , Male , Mice , Nerve Agents/adverse effects , Organophosphorus Compounds/adverse effects , Oximes/pharmacokinetics , Oximes/pharmacology , Pesticides/adverse effects , Tissue Distribution
19.
J Infect Dis ; 218(suppl_5): S592-S596, 2018 11 22.
Article in English | MEDLINE | ID: mdl-30016444

ABSTRACT

At the onset of the 2013-2016 epidemic of Ebola virus disease (EVD), no vaccine or antiviral medication was approved for treatment. Therefore, considerable efforts were directed towards the concept of drug repurposing or repositioning. Amiodarone, an approved multi-ion channel blocker for the treatment of cardiac arrhythmia, was reported to inhibit filovirus entry in vitro. Compassionate use of amiodarone in EVD patients indicated a possible survival benefit. In support of further clinical testing, we confirmed anti-Ebola virus activity of amiodarone in different cell types. Despite promising in vitro results, amiodarone failed to protect guinea pigs from a lethal dose of Ebola virus.


Subject(s)
Amiodarone/pharmacology , Ebolavirus/drug effects , Amiodarone/pharmacokinetics , Amiodarone/therapeutic use , Animals , Chlorocebus aethiops , Female , Guinea Pigs , Hemorrhagic Fever, Ebola/drug therapy , Male , Vero Cells
20.
Article in English | MEDLINE | ID: mdl-29133569

ABSTRACT

Tilorone dihydrochloride (tilorone) is a small-molecule, orally bioavailable drug that is used clinically as an antiviral outside the United States. A machine-learning model trained on anti-Ebola virus (EBOV) screening data previously identified tilorone as a potent in vitro EBOV inhibitor, making it a candidate for the treatment of Ebola virus disease (EVD). In the present study, a series of in vitro ADMET (absorption, distribution, metabolism, excretion, toxicity) assays demonstrated the drug has excellent solubility, high Caco-2 permeability, was not a P-glycoprotein substrate, and had no inhibitory activity against five human CYP450 enzymes (3A4, 2D6, 2C19, 2C9, and 1A2). Tilorone was shown to have 52% human plasma protein binding with excellent plasma stability and a mouse liver microsome half-life of 48 min. Dose range-finding studies in mice demonstrated a maximum tolerated single dose of 100 mg/kg of body weight. A pharmacokinetics study in mice at 2- and 10-mg/kg dose levels showed that the drug is rapidly absorbed, has dose-dependent increases in maximum concentration of unbound drug in plasma and areas under the concentration-time curve, and has a half-life of approximately 18 h in both males and females, although the exposure was ∼2.5-fold higher in male mice. Tilorone doses of 25 and 50 mg/kg proved efficacious in protecting 90% of mice from a lethal challenge with mouse-adapted with once-daily intraperitoneal (i.p.) dosing for 8 days. A subsequent study showed that 30 mg/kg/day of tilorone given i.p. starting 2 or 24 h postchallenge and continuing through day 7 postinfection was fully protective, indicating promising activity for the treatment of EVD.


Subject(s)
Ebolavirus/drug effects , Hemorrhagic Fever, Ebola/drug therapy , Tilorone/pharmacology , Animals , Antiviral Agents/pharmacology , Caco-2 Cells , Cell Line, Tumor , Female , Humans , Male , Mice , Mice, Inbred BALB C , Microsomes, Liver/drug effects
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