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1.
bioRxiv ; 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38654821

RESUMO

Rationale: The role of the innate immune system in Idiopathic Pulmonary Fibrosis (IPF) remains poorly understood. However, a functional myeloid compartment is required to remove dying cells and cellular debris, and to mediate innate immune responses against pathogens. Aberrant macrophage activity has been described in patients with Post-acute sequelae of COVID fibrosis (PASC-F). Therefore, we examined the functional and synthetic properties of myeloid cells isolated from normal donor lung and lung explant tissue from both IPF and PASC-F patients and explored the effect of LTI-2355, a Caveolin Scaffolding Domain (CSD) peptide, on these cells. Methods & Results: CD45 + myeloid cells isolated from lung explant tissue from IPF and PASC-F patients exhibited an impaired capacity to clear autologous dead cells and cellular debris. Uptake of pathogen-coated bioparticles was impaired in myeloid cells from both fibrotic patient groups independent of type of pathogen highlighting a cell intrinsic functional impairment. LTI-2355 improved the phagocytic activity of both IPF and PASC-F myeloid cells, and this improvement was paired with decreased pro-inflammatory and pro-fibrotic synthetic activity. LTI-2355 was also shown to primarily target CD206-expressing IPF and PASC-F myeloid cells. Conclusions: Primary myeloid cells from IPF and PASC-F patients exhibit dysfunctional phagocytic and synthetic properties that are reversed by LTI-2355. Thus, these studies highlight an additional mechanism of action of a CSD peptide in the treatment of IPF and progressive fibrotic lung disease.

2.
Clin Infect Dis ; 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37802928

RESUMO

Allergic bronchopulmonary aspergillosis and invasive fungal diseases represent distinct infectious entities that cause significant morbidity and mortality. Currently, administered inhaled antifungal therapies are unapproved, have suboptimal efficacy, and are associated with considerable adverse reactions. The emergence of resistant pathogens is also a growing concern. Inhaled antifungal development programs are challenged by inadequate nonclinical infection models, highly heterogenous patient populations, low prevalence rates of fungal diseases, difficulties defining clinical trial enrollment criteria, and lack of robust clinical trial endpoints. On September 25, 2020, the US Food and Drug Administration (FDA) convened a workshop with experts in pulmonary medicine and infectious diseases from academia, industry, and other governmental agencies. Key discussion topics included regulatory incentives to facilitate development of inhaled antifungal drugs and combination inhalational devices, limitations of existing nonclinical models and clinical trial designs, patient perspectives, and industry insights.

3.
Pharmaceutics ; 14(12)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36559062

RESUMO

Niclosamide is an FDA-approved anthelmintic that is being studied in clinical trials as a chemotherapeutic and broad-spectrum antiviral. Additionally, several other applications are currently in the preclinical stage. Unfortunately, niclosamide is a poorly water soluble molecule, with reduced oral bioavailability, which hinders its use for new indications. Moreover, niclosamide is a poor glass former; in other words, the molecule has a high tendency to recrystallize, and it is virtually impossible to generate a stable amorphous solid employing the neat molecule. Previously, our group reported the development of an amorphous solid dispersion (ASD) of niclosamide (niclosamide ASD) that generates nanoparticles during its dissolution, not only increasing niclosamide's apparent solubility from 6.6 ± 0.4 to 481.7 ± 22.2 µg/mL in fasted state simulated intestinal fluid (FaSSIF) but also its oral bioavailability 2.6-fold in Sprague-Dawley rats after being administered as a suspension. Nevertheless, niclosamide ASD undergoes recrystallization in acidic media, and an enteric oral dosage form is needed for its translation into the clinic. In this work, we further characterized the nanoparticles that generated during the dissolution of the niclosamide ASD. Cryogenic transmission electron microscopy (Cryo-TEM) and wide-angle X-ray scattering (WAXS) revealed that the nanoparticles were amorphous and had a particle size of ~150 nm. The oral dosage forms of niclosamide ASD were formulated using commercial enteric capsules (Capsuline® and EudracapTM) and as enteric-coated tablets. The enteric dosage forms were tested using pH-shift dissolution and acid-uptake tests, using the USP type II dissolution apparatus and the disintegration apparatus, respectively. The capsules exhibited a higher percentage of weight gain, and visual rupture of the Capsuline capsules was observed. Eudracap capsules protected the formulation from the acidic media, but polymer gelling and the formation of a nondispersible plug were noted during dissolution testing. In contrast, enteric-coated tablets protected the formulation from acid ingress and maintained the performance of niclosamide ASD granules during dissolution in FaSSIF media. These enteric-coated tablets were administered to beagle dogs at a niclosamide dose of 75 mg/kg, resulting in plasma concentrations of niclosamide higher than those reported in the literature using solubilized niclosamide at a higher dose (i.e., 100 mg/kg). In summary, an enteric oral dosage form of niclosamide ASD was formulated without hindering the generation of nanoparticles while maintaining the increase in the niclosamide's apparent solubility. The enteric-coated tablets successfully increased the niclosamide plasma levels in dogs when compared to a niclosamide solution prepared using organic solvents.

4.
Int J Pharm ; 624: 122021, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-35842082

RESUMO

MF59® is an oil-in-water (O/W) nanoemulsion-based vaccine adjuvant that is often used in seasonal and pandemic influenza vaccines. We explored the feasibility of developing dry powders of vaccines adjuvanted with MF59 or AddaVax™, a preclinical grade equivalent of MF59 with the same composition and droplet size as MF59, by thin-film freeze-drying (TFFD). Liquid AddaVax alone was successfully converted to a dry powder by TFFD using trehalose as a stabilizing agent while maintaining the droplet size distribution of AddaVax after it was reconstituted. TFFD was then applied to convert liquid AddaVax-adjuvanted vaccines containing either a model antigen (e.g., ovalbumin) or mono-, bi-, and tri-valent recombinant hemagglutinin (rHA) protein-based H1 and/or H3 (universal) influenza vaccine candidates, as well as the MF59-containing Fluad® Quadrivalent influenza vaccine to dry powders. Both antigens and stabilizing agents affected the physical properties of the vaccines (e.g., mean particle size and particle size distribution) after the vaccines were subjected to TFFD. Importantly, the integrity and hemagglutination activity of the rHA antigens did not significantly change and the immunogenicity of reconstituted influenza vaccine candidates was maintained when evaluated in a mouse model. The vaccine dry powder was not sensitive to repeated freezing-and-thawing, in contrast to its liquid counterpart. It is concluded that TFFD can be applied to convert liquid vaccines containing MF59 or AddaVax to dry powders while maintaining the immunogenicity of the vaccines. Ultimately, TFFD technology may be used to prepare dry powders of multivalent universal influenza vaccines.


Assuntos
Vacinas contra Influenza , Adjuvantes Imunológicos , Animais , Anticorpos Antivirais , Excipientes , Camundongos , Polissorbatos , Pós , Esqualeno
5.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445253

RESUMO

Bronchopulmonary dysplasia (BPD) is the most common complication of prematurity and a key contributor to the large health care burden associated with prematurity, longer hospital stays, higher hospital costs, and frequent re-hospitalizations of affected patients through the first year of life and increased resource utilization throughout childhood. This disease is associated with abnormal pulmonary function that may lead to BPD-associated pulmonary hypertension (PH), a major contributor to neonatal mortality and morbidity. In the absence of any definitive treatment options, this life-threatening disease is associated with high resource utilization during and after neonatal intensive care unit (NICU) stay. The goal of this study was to test the safety and efficacy of a small molecule derivative of chitin, AVR-48, as prophylactic therapy for preventing experimental BPD in a mouse model. Two doses of AVR-48 were delivered either intranasally (0.11 mg/kg), intraperitoneally (10 mg/kg), or intravenously (IV) (10 mg/kg) to newborn mouse pups on postnatal day (P)2 and P4. The outcomes were assessed by measuring total inflammatory cells in the broncho-alveolar lavage fluid (BALF), chord length, septal thickness, and radial alveolar counts of the alveoli, Fulton's Index (for PH), cell proliferation and cell death by immunostaining, and markers of inflammation by Western blotting and ELISA. The bioavailability and safety of the drug were assessed by pharmacokinetic and toxicity studies in both neonatal mice and rat pups (P3-P5). Following AVR-48 treatment, alveolar simplification was improved, as evident from chord length, septal thickness, and radial alveolar counts; total inflammatory cells were decreased in the BALF; Fulton's Index was decreased and lung inflammation and cell death were decreased, while angiogenesis and cell proliferation were increased. AVR-48 was found to be safe and the no-observed-adverse-effect level (NOAEL) in rat pups was determined to be 100 mg/kg when delivered via IV dosing with a 20-fold safety margin. With no reported toxicity and with a shorter half-life, AVR-48 is able to reverse the worsening cardiopulmonary phenotype of experimental BPD and BPD-PH, compared to controls, thus positioning it as a future drug candidate.


Assuntos
Displasia Broncopulmonar , Quitina , Hipertensão Pulmonar , Neovascularização Fisiológica/efeitos dos fármacos , Alvéolos Pulmonares , Animais , Animais Recém-Nascidos , Displasia Broncopulmonar/tratamento farmacológico , Displasia Broncopulmonar/metabolismo , Displasia Broncopulmonar/patologia , Quitina/química , Quitina/farmacologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Camundongos , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Ratos
6.
Appl Spectrosc ; 75(8): 1003-1011, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34110943

RESUMO

The global fight against mosquito-borne viral diseases has in recent years been bolstered by the introduction of the endosymbiotic bacteria Wolbachia to vector populations, which in host mosquitoes suppresses the transmissibility of several viruses. Researchers engaged on this front of the battle often need to know the Wolbachia infection status of individual mosquitoes, as the intervention progresses and the mosquitoes become established in the target population. Previously, we successfully applied attenuated total reflection Fourier transform infrared spectroscopy to the detection of Wolbachia in adult Aedes aegypti mosquitoes; here we apply the same principles to Aedes eggs, with sensitivity and selectivity > 0.95. Further, we successfully distinguish between infections in eggs of the wMel and wMelPop strains of Wolbachia pipientis, with a classification error of 3%. The disruption of host lipid profile by Wolbachia is found to be a key driver in spectral differences between these sample classes.


Assuntos
Aedes , Wolbachia , Animais , Análise de Fourier , Mosquitos Vetores , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Int J Pharm ; 603: 120701, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33989748

RESUMO

In this work, we have developed and tested a dry powder form of niclosamide made by thin-film freezing (TFF) and administered it by inhalation to rats and hamsters to gather data about its toxicology and pharmacokinetics. Niclosamide, a poorly water-soluble drug, is an interesting drug candidate because it was approved over 60 years ago for use as an anthelmintic medication, but recent studies demonstrated its potential as a broad-spectrum antiviral with pharmacological effect against SARS-CoV-2 infection. TFF was used to develop a niclosamide inhalation powder composition that exhibited acceptable aerosol performance with a fine particle fraction (FPF) of 86.0% and a mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD) of 1.11 µm and 2.84, respectively. This formulation not only proved to be safe after an acute three-day, multi-dose tolerability and exposure study in rats as evidenced by histopathology analysis, and also was able to achieve lung concentrations above the required IC90 levels for at least 24 h after a single administration in a Syrian hamster model. To conclude, we successfully developed a niclosamide dry powder inhalation that overcomes niclosamide's limitation of poor oral bioavailability by targeting the drug directly to the primary site of infection, the lungs.


Assuntos
COVID-19 , Niclosamida , Administração por Inalação , Aerossóis , Animais , Cricetinae , Inaladores de Pó Seco , Congelamento , Humanos , Tamanho da Partícula , Pós , Ratos , SARS-CoV-2
8.
Angew Chem Int Ed Engl ; 60(31): 17102-17107, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34043272

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in an unprecedented need for diagnostic testing that is critical in controlling the spread of COVID-19. We propose a portable infrared spectrometer with purpose-built transflection accessory for rapid point-of-care detection of COVID-19 markers in saliva. Initially, purified virion particles were characterized with Raman spectroscopy, synchrotron infrared (IR) and AFM-IR. A data set comprising 171 transflection infrared spectra from 29 subjects testing positive for SARS-CoV-2 by RT-qPCR and 28 testing negative, was modeled using Monte Carlo Double Cross Validation with 50 randomized test and model sets. The testing sensitivity was 93 % (27/29) with a specificity of 82 % (23/28) that included positive samples on the limit of detection for RT-qPCR. Herein, we demonstrate a proof-of-concept high throughput infrared COVID-19 test that is rapid, inexpensive, portable and utilizes sample self-collection thus minimizing the risk to healthcare workers and ideally suited to mass screening.


Assuntos
Teste para COVID-19/métodos , COVID-19/diagnóstico , Saliva/química , Animais , Chlorocebus aethiops , Estudos de Coortes , Análise Discriminante , Humanos , Análise dos Mínimos Quadrados , Método de Monte Carlo , Testes Imediatos , Estudo de Prova de Conceito , SARS-CoV-2 , Sensibilidade e Especificidade , Manejo de Espécimes , Espectrofotometria Infravermelho , Células Vero
9.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806560

RESUMO

BACKGROUND: Acute lung injury (ALI) or its most advanced form, acute respiratory distress syndrome (ARDS) is a severe inflammatory pulmonary process triggered by a variety of insults including sepsis, viral or bacterial pneumonia, and mechanical ventilator-induced trauma. Currently, there are no effective therapies available for ARDS. We have recently reported that a novel small molecule AVR-25 derived from chitin molecule (a long-chain polymer of N-acetylglucosamine) showed anti-inflammatory effects in the lungs. The goal of this study was to determine the efficacy of two chitin-derived compounds, AVR-25 and AVR-48, in multiple mouse models of ALI/ARDS. We further determined the safety and pharmacokinetic (PK) profile of the lead compound AVR-48 in rats. METHODS: ALI in mice was induced by intratracheal instillation of a single dose of lipopolysaccharide (LPS; 100 µg) for 24 h or exposed to hyperoxia (100% oxygen) for 48 h or undergoing cecal ligation and puncture (CLP) procedure and observation for 10 days. RESULTS: Both chitin derivatives, AVR-25 and AVR-48, showed decreased neutrophil recruitment and reduced inflammation in the lungs of ALI mice. Further, AVR-25 and AVR-48 mediated diminished lung inflammation was associated with reduced expression of lung adhesion molecules with improvement in pulmonary endothelial barrier function, pulmonary edema, and lung injury. Consistent with these results, CLP-induced sepsis mice treated with AVR-48 showed a significant increase in survival of the mice (80%) and improved lung histopathology in the treated CLP group. AVR-48, the lead chitin derivative compound, demonstrated a good safety profile. CONCLUSION: Both AVR-25 and AVR-48 demonstrate the potential to be developed as therapeutic agents to treat ALI/ARDS.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Fatores Imunológicos/farmacologia , Síndrome do Desconforto Respiratório/tratamento farmacológico , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Quitina/farmacologia , Modelos Animais de Doenças , Feminino , Lipopolissacarídeos/farmacologia , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pneumonia/tratamento farmacológico , Edema Pulmonar/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Sepse/tratamento farmacológico
10.
Int J Pharm X ; 3: 100073, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34977555

RESUMO

Remdesivir dry powder for inhalation was previously developed using thin film freezing (TFF). A single-dose 24-h pharmacokinetic study in hamsters demonstrated that pulmonary delivery of TFF remdesivir can achieve plasma remdesivir and GS-441524 levels higher than the reported EC50s of both remdesivir and GS-441524 (in human epithelial cells) over 20 h. The half-life of GS-4412524 following dry powder insufflation was about 7 h, suggesting the dosing regimen would be twice-daily administration. Although the remdesivir-Captisol® (80/20 w/w) formulation showed faster and greater absorption of remdesivir and GS-4412524 in the lung, remdesivir-leucine (80/20 w/w) exhibited a greater Cmax with shorter Tmax and lower AUC of GS-441524, indicating lower total drug exposure is required to achieve a high effective concentration against SAR-CoV-2. In conclusion, remdesivir dry powder for inhalation would be a promising alternative dosage form for the treatment of COVID-19 disease.

11.
Food Chem ; 338: 127947, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32947120

RESUMO

Hydrogen peroxide (H2O2) is a reactive oxygen species (ROS) that mediates essential signaling in vivo but may cause irreversible tissue damage under dysregulated or acute exposure conditions. Beverages containing redox-active compounds might produce H2O2 during shelf storage and potentially be consumed. Concentrations of H2O2 in selected 'functional' (including energy, E, n = 28), 'non-functional' flavored, (S, n = 6) and mineral water (W, n = 6) drinks were measured under ambient (i.e., produced in situ) and 'potentiated' conditions (i.e., H2O2 production enhanced by addition of a reducing agent, to simulate availability of reducible substrates in vivo). Under air-saturated conditions, mean H2O2 contents were: 15.60 ± 15.84; 1.39 ± 2.06 and 0.30 ± 0.21 µM in E, S and W drinks, respectively. Under air-saturated, potentiated conditions, mean rates of H2O2 production were 21.7 ± 33.3, 0.98 ± 2.84, and -0.38 ± 1.18 µM/h for E, S and W drinks, respectively. Using multivariate statistics, the ingredient significantly associated with H2O2 production in combination with other ingredients was found to be ascorbic acid.


Assuntos
Ácido Ascórbico/química , Bebidas/análise , Peróxido de Hidrogênio/química , Oxirredução
12.
Pharmaceutics ; 12(11)2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33105618

RESUMO

Remdesivir exhibits in vitro activity against SARS-CoV-2 and was granted approval for emergency use. To maximize delivery to the lungs, we formulated remdesivir as a dry powder for inhalation using thin film freezing (TFF). TFF produces brittle matrix nanostructured aggregates that are sheared into respirable low-density microparticles upon aerosolization from a passive dry powder inhaler. In vitro aerodynamic testing demonstrated that drug loading and excipient type affected the aerosol performance of remdesivir. Remdesivir combined with optimal excipients exhibited desirable aerosol performance (up to 93.0% FPF< 5 µm; 0.82 µm mass median aerodynamic diameter). Remdesivir was amorphous after the TFF process, which benefitted drug dissolution in simulated lung fluid. TFF remdesivir formulations are stable after one month of storage at 25 °C/60% relative humidity. An in vivo pharmacokinetic evaluation showed that TFF remdesivir-leucine was poorly absorbed into systemic circulation while TFF remdesivir-Captisol® demonstrated increased systemic uptake compared to leucine. Remdesivir was hydrolyzed to the nucleoside analog GS-441524 in the lung, and levels of GS-441524 were greater in the lung with leucine formulation compared to Captisol®. In conclusion, TFF technology produces high-potency remdesivir dry powder formulations for inhalation that are suitable to treat patients with COVID-19 on an outpatient basis and earlier in the disease course where effective antiviral therapy can reduce related morbidity and mortality.

14.
Annu Rev Anal Chem (Palo Alto Calif) ; 12(1): 89-108, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-30978292

RESUMO

Vibrational spectroscopy has contributed to the understanding of biological materials for many years. As the technology has advanced, the technique has been brought to bear on the analysis of whole organisms. Here, we discuss advanced and recently developed infrared and Raman spectroscopic instrumentation to whole-organism analysis. We highlight many of the recent contributions made in this relatively new area of spectroscopy, particularly addressing organisms associated with disease with emphasis on diagnosis and treatment. The application of vibrational spectroscopic techniques to entire organisms is still in its infancy, but new developments in imaging and chemometric processing will likely expand in the field in the near future.


Assuntos
Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Animais , Desenho de Equipamento , Humanos , Malária/diagnóstico , Malária/tratamento farmacológico , Malária/parasitologia , Micoses/diagnóstico , Micoses/tratamento farmacológico , Micoses/microbiologia , Plasmodium/química , Plasmodium/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier/instrumentação , Análise Espectral Raman/instrumentação , Leveduras/química , Leveduras/efeitos dos fármacos
15.
Br J Haematol ; 184(4): 605-615, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30443898

RESUMO

Alteration in RNA splicing is implicated in carcinogenesis and progression. Mutations in spliceosome genes and alternative splicing of other genes have been noted in chronic lymphocytic leukaemia (CLL), a common B cell malignancy with heterogeneous outcomes. We previously demonstrated that differences in the amount of SET oncoprotein (a physiological inhibitor of the serine/threonine phosphatase, PP2A) is associated with clinical aggressiveness in patients with CLL. It is unknown if alternative splicing of gene transcripts regulating kinases and phosphatases affects disease pathobiology and CLL progression. We show here for the first time that mRNA levels of the alternatively spliced SET isoforms, SETA and SETB (SETα and SETß), significantly correlate with disease severity (overall survival and time-to-first-treatment) in CLL patients. In addition, we demonstrate that relative increase of SETA to SETB mRNA can discriminate patients with a more aggressive disease course within the otherwise favourable CLL risk classifications of IGHV mutated and favourable hierarchical fluorescence in situ hybridisation groups. We validate our finding by showing comparable relationships of SET mRNA with disease outcomes using samples from an independent CLL cohort from a separate institution. These findings indicate that alternative splicing of SET, and potentially other signalling cascade molecules, influences CLL biology and patient outcomes.


Assuntos
Chaperonas de Histonas , Leucemia Linfocítica Crônica de Células B , Proteínas de Neoplasias , RNA Mensageiro , RNA Neoplásico , Fatores de Transcrição , Adulto , Idoso , Idoso de 80 Anos ou mais , Processamento Alternativo , Proteínas de Ligação a DNA , Intervalo Livre de Doença , Feminino , Chaperonas de Histonas/biossíntese , Chaperonas de Histonas/genética , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/mortalidade , Leucemia Linfocítica Crônica de Células B/terapia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Taxa de Sobrevida , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
16.
Cancer Res ; 79(1): 209-219, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30389701

RESUMO

In cancer, kinases are often activated and phosphatases suppressed, leading to aberrant activation of signaling pathways driving cellular proliferation, survival, and therapeutic resistance. Although pancreatic ductal adenocarcinoma (PDA) has historically been refractory to kinase inhibition, therapeutic activation of phosphatases is emerging as a promising strategy to restore balance to these hyperactive signaling cascades. In this study, we hypothesized that phosphatase activation combined with kinase inhibition could deplete oncogenic survival signals to reduce tumor growth. We screened PDA cell lines for kinase inhibitors that could synergize with activation of protein phosphatase 2A (PP2A), a tumor suppressor phosphatase, and determined that activation of PP2A and inhibition of mTOR synergistically increase apoptosis and reduce oncogenic phenotypes in vitro and in vivo. This combination treatment resulted in suppression of AKT/mTOR signaling coupled with reduced expression of c-MYC, an oncoprotein implicated in tumor progression and therapeutic resistance. Forced expression of c-MYC or loss of PP2A B56α, the specific PP2A subunit shown to negatively regulate c-MYC, increased resistance to mTOR inhibition. Conversely, decreased c-MYC expression increased the sensitivity of PDA cells to mTOR inhibition. Together, these studies demonstrate that combined targeting of PP2A and mTOR suppresses proliferative signaling and induces cell death and implicates this combination as a promising therapeutic strategy for patients with PDA. SIGNIFICANCE: These findings present a combinatorial strategy targeting serine/threonine protein phosphatase PP2A and mTOR in PDA, a cancer for which there are currently no targeted therapeutic options.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/79/1/209/F1.large.jpg.


Assuntos
Benzoxazóis/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Sinergismo Farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Proteína Fosfatase 2/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Pirimidinas/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Apoptose , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Ativação Enzimática , Humanos , Camundongos , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Proteína Fosfatase 2/química , Proteínas Proto-Oncogênicas c-akt , Proteínas Proto-Oncogênicas c-myc/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Neoplasias Pancreáticas
17.
Inhal Toxicol ; 29(8): 356-365, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28984146

RESUMO

BACKGROUND: ENaC inhibition has long been an attractive therapeutic target for the treatment of cystic fibrosis. However, previous attempts at developing ENaC inhibitors have been unsuccessful due to complications arising from systemic circulation of the compounds. Here, we describe the preclinical toxicology assessment of a new inhaled peptide promoter of ENaC internalization delivered as a nebulized aerosol. METHODS: Preclinical assessment of SPX-101 safety was determined using an in vitro hERG assay, bolus injection of SPX-101 in a canine cardiovascular and respiratory safety pharmacology model and 28-day inhalation toxicology studies of nebulized drug in rats and dogs. RESULTS: SPX101 had no effects on the respiratory, cardiac or central nervous systems. The 28-day inhalation toxicology studies of nebulized SPX-101 in rats and dogs revealed no drug-related adverse events. Plasma levels of SPX-101 peaked less than 1 h after the end of treatment in rats and were below the limit of detection in canine models. CONCLUSIONS: SPX-101, a novel peptide promoter of ENaC internalization, elicited no adverse effects at doses up to the MFD and in excess of the highest preclinical efficacious and expected clinical doses. In contrast to channel blockers like amiloride and derivative small molecules, SPX-101 does not achieve significant systemic circulation, thus doses are not limited due to toxic side effects like hyperkalemia and weight loss.


Assuntos
Peptídeos/toxicidade , Administração por Inalação , Animais , Fibrose Cística/tratamento farmacológico , Cães , Canal de Potássio ERG1/fisiologia , Canais Epiteliais de Sódio/metabolismo , Feminino , Glicoproteínas , Células HEK293 , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Peptídeos/sangue , Peptídeos/farmacocinética , Peptídeos/farmacologia , Fosfoproteínas , Ratos Sprague-Dawley , Testes de Toxicidade Subaguda
18.
Am J Respir Crit Care Med ; 196(6): 734-744, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28481660

RESUMO

RATIONALE: Cystic fibrosis (CF) lung disease is caused by the loss of function of the cystic fibrosis transmembrane conductance regulator (CFTR) combined with hyperactivation of the epithelial sodium channel (ENaC). In the lung, ENaC is responsible for movement of sodium. Hyperactivation of ENaC, which creates an osmotic gradient that pulls fluid out of the airway, contributes to reduced airway hydration, causing mucus dehydration, decreased mucociliary clearance, and recurrent acute bacterial infections. ENaC represents a therapeutic target to treat all patients with CF independent of their underlying CFTR mutation. OBJECTIVES: To investigate the in vitro and in vivo efficacy of SPX-101, a peptide mimetic of the natural regulation of ENaC activity by short palate, lung, and nasal epithelial clone 1, known as SPLUNC1. METHODS: ENaC internalization by SPX-101 in primary human bronchial epithelial cells from healthy and CF donors was assessed by surface biotinylation and subsequent Western blot analysis. SPX-101's in vivo therapeutic effect was assessed by survival of ß-ENaC-transgenic mice, mucus transport in these mice, and mucus transport in a sheep model of CF. MEASUREMENTS AND MAIN RESULTS: SPX-101 binds selectively to ENaC and promotes internalization of the α-, ß-, and γ-subunits. Removing ENaC from the membrane with SPX-101 causes a significant decrease in amiloride-sensitive current. The peptide increases survival of ß-ENaC-transgenic mice to greater than 90% with once-daily dosing by inhalation. SPX-101 increased mucus transport in the ß-ENaC mouse model as well as the sheep model of CF. CONCLUSIONS: These data demonstrate that SPX-101 promotes durable reduction of ENaC membrane concentration, leading to significant improvements in mucus transport.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/uso terapêutico , Fibrose Cística/tratamento farmacológico , Bloqueadores do Canal de Sódio Epitelial/uso terapêutico , Canais Epiteliais de Sódio/uso terapêutico , Depuração Mucociliar/efeitos dos fármacos , Mucosa Respiratória/efeitos dos fármacos , Humanos
19.
Anal Chem ; 89(10): 5285-5293, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28332822

RESUMO

Dengue fever is the most common mosquito transmitted viral infection afflicting humans, estimated to generate around 390 million infections each year in over 100 countries. The introduction of the endosymbiotic bacterium Wolbachia into Aedes aegypti mosquitoes has the potential to greatly reduce the public health burden of the disease. This approach requires extensive polymerase chain reaction (PCR) testing of the Wolbachia-infection status of mosquitoes in areas where Wolbachia-A. aegypti are released. Here, we report the first example of small organism mid-infrared spectroscopy where we have applied attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectroscopy and multivariate modeling methods to determine sex, age, and the presence of Wolbachia (wMel strain) in laboratory mosquitoes and sex and age in field mosquitoes. The prediction errors using partial least squares discriminant analysis (PLS-DA) discrimination models for laboratory studies on independent test sets ranged from 0 to 3% for age and sex grading and 3% to 5% for Wolbachia infection diagnosis using dry mosquito abdomens while field study results using an artificial neural network yielded a 10% error. The application of FT-IR analysis is inexpensive, easy to use, and portable and shows significant potential to replace the reliance on more expensive and laborious PCR assays.


Assuntos
Aedes/microbiologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Wolbachia/patogenicidade , Aedes/química , Envelhecimento , Animais , Análise Discriminante , Feminino , Análise dos Mínimos Quadrados , Masculino , Fatores Sexuais , Simbiose , Wolbachia/fisiologia
20.
Oncotarget ; 7(51): 84214-84227, 2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-27705940

RESUMO

Recent evidence suggests that inhibition of protein phosphatase 2A (PP2A) tumor suppressor activity via the SET oncoprotein contributes to the pathogenesis of various cancers. Here we demonstrate that both SET and c-MYC expression are frequently elevated in T-ALL cell lines and primary samples compared to healthy T cells. Treatment of T-ALL cells with the SET antagonist OP449 restored the activity of PP2A and reduced SET interaction with the PP2A catalytic subunit, resulting in a decrease in cell viability and c-MYC expression in a dose-dependent manner. Since a tight balance between phosphatases and kinases is required for the growth of both normal and malignant cells, we sought to identify a kinase inhibitor that would synergize with SET antagonism. We tested various T-ALL cell lines against a small-molecule inhibitor screen of 66 compounds targeting two-thirds of the tyrosine kinome and found that combined treatment of T-ALL cells with dovitinib, an orally active multi-targeted small-molecule receptor tyrosine kinase inhibitor, and OP449 synergistically reduced the viability of all tested T-ALL cell lines. Mechanistically, combined treatment with OP449 and dovitinib decreased total and phospho c-MYC levels and reduced ERK1/2, AKT, and p70S6 kinase activity in both NOTCH-dependent and independent T-ALL cell lines. Overall, these results suggest that combined targeting of tyrosine kinases and activation of serine/threonine phosphatases may offer novel therapeutic strategies for the treatment of T-ALL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Chaperonas de Histonas/antagonistas & inibidores , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Proteínas Tirosina Quinases/antagonistas & inibidores , Fatores de Transcrição/antagonistas & inibidores , Adolescente , Adulto , Idoso , Benzimidazóis/administração & dosagem , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Criança , Proteínas de Ligação a DNA , Inibidores Enzimáticos/administração & dosagem , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Chaperonas de Histonas/genética , Chaperonas de Histonas/metabolismo , Humanos , Células Jurkat , Masculino , Peptídeos/administração & dosagem , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Proteína Fosfatase 2/antagonistas & inibidores , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Quinolonas/administração & dosagem , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Adulto Jovem
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