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1.
Pharmaceutics ; 14(8)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35893781

RESUMO

Lung cancer is one of the major causes of cancer-related deaths worldwide, primarily because of the limitations of conventional clinical therapies such as chemotherapy and radiation therapy. Side effects associated with these treatments have made it essential for new modalities, such as tumor targeting nanoparticles that can provide cancer specific therapies. In this research, we have developed novel dual-stimuli nanoparticles (E-DSNPs), comprised of two parts; (1) Core: responsive to glutathione as stimuli and encapsulating Cisplatin (a chemo-drug), and (2) Shell: responsive to irradiation as stimuli and containing NU7441 (a radiation sensitizer). The targeting moieties on these nanoparticles are Ephrin transmembrane receptors A2 (EphA2) that are highly expressed on the surfaces of lung cancer cells. These nanoparticles were then evaluated for their enhanced targeting and therapeutic efficiency against lung cancer cell lines. E-DSNPs displayed very high uptake by lung cancer cells compared to healthy lung epithelial cells. These nanoparticles also demonstrated a triggered release of both drugs against respective stimuli and a subsequent reduction in in vitro cancer cell survival fraction compared to free drugs of equivalent concentration (survival fraction of about 0.019 and 0.19, respectively). Thus, these nanoparticles could potentially pave the path to targeted cancer therapy, while overcoming the side effects of conventional clinical therapies.

2.
J Control Release ; 321: 363-371, 2020 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-32061622

RESUMO

Lung cancer is one of the major causes of cancer-related deaths worldwide. Stimuli-responsive polymers and nanoparticles, which respond to exogenous or endogenous stimuli in the tumor microenvironment, have been widely investigated for spatiotemporal chemotherapeutic drug release applications for cancer chemotherapy. We developed glutathione (GSH)-responsive polyurethane nanoparticles (GPUs) using a GSH-cleavable disulfide bond containing polyurethane that responds to elevated levels of GSH within lung cancer cells. The polyurethane nanoparticles were fabricated using a single emulsion and mixed organic solvent method. Cisplatin-loaded GSH-sensitive nanoparticles (CGPU) displayed a GSH-dose dependent release of cisplatin. In addition, a significant reduction in in vitro survival fraction of A549 lung cancer cells was observed compared to free cisplatin of equivalent concentration (survival fraction of ~0.5 and ~0.7, respectively). The in vivo biodistribution studies showed localization of fluorescently labeled GPUs (~7% of total injected dose per gram tissue) in the lung tumor regions after mouse-tail IV injections in xenograft A549 lung tumor models. The animals exposed to CGPUs also exhibited the inhibition of lung tumor growth compared to animals administered with saline (tumor growth rate of 1.5 vs. 13 in saline) and free cisplatin (tumor growth rate of 5.9) in mouse xenograft A549 lung tumor models within 14 days. These nanoparticles have potential to be used for on-demand drug release for an enhanced chemotherapy to effectively treat lung cancer.


Assuntos
Antineoplásicos , Portadores de Fármacos , Glutationa , Neoplasias Pulmonares , Nanopartículas , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Portadores de Fármacos/uso terapêutico , Glutationa/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Poliuretanos , Distribuição Tecidual , Microambiente Tumoral
3.
PLoS One ; 14(4): e0214581, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30934006

RESUMO

Leeches and oligochaetes comprise a monophyletic group of annelids, the Clitellata, whose reproduction is characterized by simultaneous hermaphroditism. While most clitellate species reproduce by cross-fertilization, self-fertilization has been described within the speciose genus Helobdella. Here we document the reproductive life histories and reproductive capacities for three other Helobdella species. Under laboratory conditions, both H. robusta and H. octatestisaca exhibit uniparental reproduction, apparently reflecting self-fertility, and suggesting that this trait is ancestral for the genus. However, the third species, H. austinensis, seems incapable of reproduction by self-fertilization, so we inferred its reproductive life history by analyzing reproduction in breeding cohorts. Comparing the reproductive parameters for H. robusta reproducing in isolation and in cohorts revealed that reproduction in cohorts is dramatically delayed with respect to that of isolated individuals, and that cohorts of leeches coordinate their cocoon deposition in a manner that is not predicted from the reproductive parameters of individuals reproducing in isolation. Finally, our comparisons of reproductive capacity for individuals versus cohorts for H. robusta, and between different sizes of cohorts for H. austinensis, reveal differences in resource allocation between male and female reproductive roles that are consistent with evolutionary theory.


Assuntos
Sanguessugas/fisiologia , Comportamento Sexual Animal , Especificidade da Espécie , Animais , Evolução Biológica , Simulação por Computador , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Fertilização , Funções Verossimilhança , Masculino , Método de Monte Carlo , Óvulo , Filogenia , Pigmentação , Espermatozoides
4.
Am J Physiol Lung Cell Mol Physiol ; 316(5): L936-L945, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30785346

RESUMO

Paracrine erythropoietin (EPO) signaling in the lung recruits endothelial progenitor cells, promotes cell maturation and angiogenesis, and is upregulated during canine postpneumonectomy (PNX) compensatory lung growth. To determine whether inhalational delivery of exogenous EPO augments endogenous post-PNX lung growth, adult canines underwent right PNX and received, via a permanent tracheal stoma, weekly nebulization of recombinant human EPO-containing nanoparticles or empty nanoparticles (control) for 16 wk. Lung function was assessed under anesthesia pre- and post-PNX. The remaining lobes were fixed for detailed morphometric analysis. Compared with control treatment, EPO delivery significantly increased serum EPO concentration without altering systemic hematocrit or hemoglobin concentration and abrogated post-PNX lipid oxidative stress damage. EPO delivery modestly increased post-PNX volume densities of the alveolar septum per unit of lung volume and type II epithelium and endothelium per unit of septal tissue volume in selected lobes. EPO delivery also augmented the post-PNX increase in alveolar double-capillary profiles, a marker of intussusceptive capillary formation, in all remaining lobes. EPO treatment did not significantly alter absolute resting lung volumes, lung and membrane diffusing capacities, alveolar-capillary blood volume, pulmonary blood flow, lung compliance, or extravascular alveolar tissue volumes or surface areas. Results established the feasibility of chronic inhalational delivery of growth-modifying biologics in a large animal model. Exogenous EPO selectively enhanced cytoprotection and alveolar angiogenesis in remaining lobes but not whole-lung extravascular tissue growth or resting function; the nonuniform response contributes to structure-function discrepancy, a major challenge for interventions aimed at amplifying the innate potential for compensatory lung growth.


Assuntos
Capilares/crescimento & desenvolvimento , Eritropoetina/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Pneumonectomia , Alvéolos Pulmonares , Administração por Inalação , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Cães , Complacência Pulmonar/efeitos dos fármacos , Masculino , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Alvéolos Pulmonares/cirurgia
5.
Antioxid Redox Signal ; 30(17): 1983-1998, 2019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-29808718

RESUMO

Aims: Epidemiologic evidence indicates that diabetes may increase risk of breast cancer (BC) and mortality in patients with cancer. The pathophysiological relationships between diabetes and cancer are not fully understood, and personalized treatments for diabetes-associated BC are urgently needed. Results: We observed that high glucose (HG), via activation of nuclear phosphatase PP2Cδ, suppresses p53 function, and consequently promotes BC cell proliferation, migration, and invasion. PP2Cδ expression is higher in tumor tissues from BC patients with hyperglycemia than those with normoglycemia. The mechanisms underlying HG stimulation of PP2Cδ involve classical/novel protein kinase-C (PKC) activation and GSK3ß phosphorylation. Reactive oxygen species (ROS)/NF-κB pathway also mediates HG induction of PP2Cδ. Furthermore, we identified a 1,5-diheteroarylpenta-1,4-dien-3-one (Compound 23, or C23) as a novel potent PP2Cδ inhibitor with a striking cytotoxicity on MCF-7 cells through cell-based screening assay for growth inhibition and activity of a group of curcumin mimics. Beside directly inhibiting PP2Cδ activity, C23 blocks HG induction of PP2Cδ expression via heat shock protein 27 (HSP27) induction and subsequent ablation of ROS/NF-κB activation. C23 can thus significantly block HG-triggered inhibition of p53 activity, leading to the inhibition of cancer cell proliferation, migration, and invasion. In addition, hyperglycemia promotes BC development in diabetic nude mice, and C23 inhibits the xenografted BC tumor growth. Conclusions and Innovation: Our findings elucidate mechanisms that may have contributed to diabetes-associated BC progression, and provide the first evidence to support the possible alternative therapeutic approach to BC patients with diabetes. Antioxid. Redox Signal. 30, 1983-1998.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Curcumina/farmacologia , Inibidores Enzimáticos/farmacologia , Glucose/metabolismo , Proteína Fosfatase 2C/antagonistas & inibidores , Acetilação , Animais , Antineoplásicos/química , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Curcumina/análogos & derivados , Curcumina/química , Modelos Animais de Doenças , Progressão da Doença , Inibidores Enzimáticos/química , Feminino , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Hiperglicemia , Camundongos , Modelos Moleculares , NF-kappa B/metabolismo , Fosforilação , Proteína Fosfatase 2C/química , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Int J Pharm ; 554: 212-223, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30408532

RESUMO

Nanoparticles (NPs) can be used to locally deliver anti-restenosis drugs when they are infused directly to the injured arteries after intervention procedures such as angioplasty. However, the efficacy of transferring NPs via infusion to the arterial wall is limited, at least partially, due to poor NP retention on the inner artery wall. To improve NP retention, angioplasty balloons coated with drug-loaded NPs were fabricated via either layer-by-layer (LbL) electrostatic coating or acrylic-based hydrogel (AAH) coating techniques. Three types of NPs, namely poly (lactide-co-glycolide) (PLGA), biodegradable photo-luminescent PLGA and urethane doped polyester were studied. The transfer efficacy of NPs from various coatings to the arterial wall were further evaluated to find the optimal coating conditions. The ex vivo NP transfer studies showed significantly more NPs being transferred to the rat arterial wall after the angioplasty procedure by the AAH coating (95% transfer efficiency) compared to that of the LbL technique (60%) and dip coating (20%) under flow conditions (10 dyn/cm2). Our results suggest that the AAH coating of drug-loaded NPs on the angioplasty balloon could potentially provide superior retention of drug-loaded NPs onto the arterial wall for a better local delivery of drug-loaded NPs to effectively treat arterial diseases.


Assuntos
Angioplastia Coronária com Balão/métodos , Reestenose Coronária/prevenção & controle , Sistemas de Liberação de Medicamentos , Nanopartículas , Animais , Artérias/metabolismo , Doenças Cardiovasculares/terapia , Substâncias Luminescentes/química , Poliésteres/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos , Uretana/química
7.
Sci Rep ; 7(1): 13249, 2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-29038584

RESUMO

Late-stage diagnosis of lung cancer occurs ~95% of the time due to late manifestation of its symptoms, necessitating rigorous treatment following diagnosis. Existing treatment methods are limited by lack of specificity, systemic toxicity, temporary remission, and radio-resistance in lung cancer cells. In this research, we have developed a folate receptor-targeting multifunctional dual drug-loaded nanoparticle (MDNP) containing a poly(N-isopropylacrylamide)-carboxymethyl chitosan shell and poly lactic-co-glycolic acid (PLGA) core for enhancing localized chemo-radiotherapy to effectively treat lung cancers. The formulation provided controlled releases of the encapsulated therapeutic compounds, NU7441 - a potent radiosensitizer, and gemcitabine - an FDA approved chemotherapeutic drug for lung cancer chemo-radiotherapy. The MDNPs showed biphasic NU7441 release and pH-dependent release of gemcitabine. These nanoparticles also demonstrated good stability, excellent hemocompatibility, outstanding in vitro cytocompatibility with alveolar Type I cells, and dose-dependent caveolae-mediated in vitro uptake by lung cancer cells. In addition, they could be encapsulated with superparamagnetic iron oxide (SPIO) nanoparticles and visualized by MRI in vivo. Preliminary in vivo results demonstrated the low toxicity of these particles and their use in chemo-radiotherapy to effectively reduce lung tumors. These results indicate that MDNPs can potentially be used as nano-vehicles to provide simultaneous chemotherapy and radiation sensitization for lung cancer treatment.


Assuntos
Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Linhagem Celular Tumoral , Quitosana/análogos & derivados , Quitosana/química , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
8.
J Appl Physiol (1985) ; 121(1): 312-23, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27150830

RESUMO

Following pneumonectomy (PNX), two separate mechanical forces act on the remaining lung: parenchymal stress caused by lung expansion, and microvascular distension and shear caused by increased perfusion. We previously showed that parenchymal stress and strain explain approximately one-half of overall compensation; the remainder was presumptively attributed to perfusion-related factors. In this study, we directly tested the hypothesis that perturbation of regional pulmonary perfusion modulates post-PNX lung growth. Adult canines underwent banding of the pulmonary artery (PAB) to the left caudal (LCa) lobe, which caused a reduction in basal perfusion to LCa lobe without preventing the subsequent increase in its perfusion following right PNX while simultaneously exaggerating the post-PNX increase in perfusion to the unbanded lobes, thereby creating differential perfusion changes between banded and unbanded lobes. Control animals underwent sham pulmonary artery banding followed by right PNX. Pulmonary function, regional pulmonary perfusion, and high-resolution computed tomography of the chest were analyzed pre-PNX and 3-mo post-PNX. Terminally, the remaining lobes were fixed for detailed morphometric analysis. Results were compared with corresponding lobes in two control (Sham banding and normal unoperated) groups. PAB impaired the indices of post-PNX extravascular alveolar tissue growth by up to 50% in all remaining lobes. PAB enhanced the expected post-PNX increase in alveolar capillary formation, measured by the prevalence of double-capillary profiles, in both unbanded and banded lobes. We conclude that perfusion distribution provides major stimuli for post-PNX compensatory lung growth independent of the stimuli provided by lung expansion and parenchymal stress and strain.


Assuntos
Pulmão/fisiologia , Regeneração/fisiologia , Animais , Capilares/fisiologia , Cães , Medidas de Volume Pulmonar/métodos , Masculino , Perfusão/métodos , Pneumonectomia/métodos , Artéria Pulmonar/fisiologia , Troca Gasosa Pulmonar/fisiologia , Estresse Mecânico , Tomografia Computadorizada por Raios X/métodos
9.
Curr Pharm Des ; 21(36): 5233-44, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26412358

RESUMO

Inhalation of aerosolized compounds is a popular, non-invasive route for the targeted delivery of therapeutic molecules to the lung. Various types of nanoparticles have been used as carriers to facilitate drug uptake and intracellular action in order to treat lung diseases and/or to facilitate lung repair and growth. These include polymeric nanoparticles, liposomes, and dendrimers, among many others. In addition, nanoparticles are sometimes used in combination with small molecules, cytokines, growth factors, and/or pluripotent stem cells. Here we review the rationale and state-of-the-art nanotechnology for pulmonary drug delivery, with particular attention to new technological developments and approaches as well as the challenges associated with them, the emerging advances, and opportunities for future development in this field.


Assuntos
Sistemas de Liberação de Medicamentos , Pulmão/metabolismo , Nanopartículas , Administração por Inalação , Aerossóis , Animais , Dendrímeros/química , Portadores de Fármacos/metabolismo , Humanos , Lipossomos , Pneumopatias/tratamento farmacológico , Nanotecnologia/métodos , Polímeros/química , Distribuição Tecidual
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