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1.
J Biomed Sci ; 31(1): 81, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164686

RESUMO

BACKGROUND: Betulinic acid (BA) has been well investigated for its antiproliferative and mitochondrial pathway-mediated apoptosis-inducing effects on various cancers. However, its poor solubility and off-target activity have limited its utility in clinical trials. Additionally, the immune modulatory role of betulinic acid analogue in the tumor microenvironment (TME) is largely unknown. Here, we designed a potential nanotherapy for colorectal cancer (CRC) with a lead betulinic acid analogue, named as 2c, carrying a 1,2,3-triazole-moiety attached to BA through a linker, found more effective than BA for inhibiting CRC cell lines, and was chosen here for this investigation. Epithelial cell adhesion molecule (EpCAM) is highly overexpressed on the CRC cell membrane. A single-stranded short oligonucleotide sequence, aptamer (Apt), that folds into a 3D-defined architecture can be used as a targeting ligand for its specific binding to a target protein. EpCAM targeting aptamer was designed for site-specific homing of aptamer-conjugated-2c-loaded nanoparticles (Apt-2cNP) at the CRC tumor site to enhance therapeutic potential and reduce off-target toxicity in normal cells. We investigated the in vitro and in vivo therapeutic efficacy and anti-tumorigenic immune response of aptamer conjugated nanotherapy in CRC-TME. METHODS: After the characterization of nanoengineered aptamer conjugated betulinic acid nanotherapy, we evaluated therapeutic efficacy, tumor targeting efficiency, and anti-tumorigenic immune response using cell-based assays and mouse and rat models. RESULTS: We found that Apt-2cNP improved drug bioavailability, enhanced its biological half-life, improved antiproliferative activity, and minimized off-target cytotoxicity. Importantly, in an in vivo TME, Apt-2cNP showed promising signs of anti-tumorigenic immune response (increased mDC/pDC ratio, enhanced M1 macrophage population, and CD8 T-cells). Furthermore, in vivo upregulation of pro-apoptotic while downregulation of anti-apoptotic genes and significant healing efficacy on cancer tissue histopathology suggest that Apt-2cNP had predominantly greater therapeutic potential than the non-aptamer-conjugated nanoparticles and free drug. Moreover, we observed greater tumor accumulation of the radiolabeled Apt-2cNP by live imaging in the CRC rat model. CONCLUSIONS: Enhanced therapeutic efficacy and robust anti-tumorigenic immune response of Apt-2cNP in the CRC-TME are promising indicators of its potential as a prospective therapeutic agent for managing CRC. However, further studies are warranted.


Assuntos
Ácido Betulínico , Neoplasias Colorretais , Molécula de Adesão da Célula Epitelial , Triterpenos Pentacíclicos , Microambiente Tumoral , Neoplasias Colorretais/tratamento farmacológico , Animais , Microambiente Tumoral/efeitos dos fármacos , Camundongos , Triterpenos Pentacíclicos/farmacologia , Molécula de Adesão da Célula Epitelial/metabolismo , Humanos , Nanopartículas/química , Linhagem Celular Tumoral , Ratos
2.
Environ Sci Technol ; 57(22): 8225-8235, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37220346

RESUMO

Plastic cutting boards are a potentially significant source of microplastics in human food. Thus, we investigated the impact of chopping styles and board materials on microplastics released during chopping. As chopping progressed, the effects of chopping styles on microplastic release became evident. The mass and number of microplastics released from polypropylene chopping boards were greater than polyethylene by 5-60% and 14-71%, respectively. Chopping on polyethylene boards was associated with a greater release of microplastics with a vegetable (i.e., carrots) than chopping without carrots. Microplastics showed a broad, bottom-skewed normal distribution, dominated by <100 µm spherical-shaped microplastics. Based on our assumptions, we estimated a per-person annual exposure of 7.4-50.7 g of microplastics from a polyethylene chopping board and 49.5 g of microplastics from a polypropylene chopping board. We further estimated that a person could be exposed to 14.5 to 71.9 million polyethylene microplastics annually, compared to 79.4 million polypropylene microplastics from chopping boards. The preliminary toxicity study of the polyethylene microplastics did not show adverse effects on the viability of mouse fibroblast cells for 72 h. This study identifies plastic chopping boards as a substantial source of microplastics in human food, which requires careful attention.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Camundongos , Humanos , Plásticos , Polipropilenos , Poluentes Químicos da Água/análise , Polietileno/análise , Monitoramento Ambiental
3.
Langmuir ; 38(6): 2066-2075, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35119869

RESUMO

We studied self-assembly and colloidal properties of poly(ethylene glycol) (pEG) conjugated sucrose soyate polyols (PSSP). These molecular platforms were synthesized by covalently connecting PEGs of different molecular weights (Mn) (12 and 16 ethylene oxide units) to epoxidized sucrose soyate (ESS). The synthesized PSSP products showed amphiphilicity, reduced water surface tension, and exhibited critical Aggregation Concentration (CAC) within the range of 0.3-0.4 mg/mL. We observed that PSSP self-assembles in water in the form of nanoparticles without the need of any cosolvents. These nanoparticles exhibited number-average hydrodynamic diameter of 120 ± 8 nm with a polydispersity index (PDI) of <0.3, and negatively charged surfaces. We also found out that PSSP nanoparticles can encapsulate and homogeneously distribute a hydrophobic model compound, such as a phthalocyanine dye, Solvent Blue-70 (BL-70), on a metal surface. Collectively, our studies explored and demonstrated the possibility of molecular diversification of biobased starting materials to form amphiphilic nanoparticles with industrially relevant colloidal and surface properties.


Assuntos
Nanoestruturas , Sacarose , Interações Hidrofóbicas e Hidrofílicas , Micelas , Nanoestruturas/química , Polietilenoglicóis/química
4.
Mol Pharm ; 18(1): 87-100, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33231464

RESUMO

Pancreatic ductal adenocarcinoma (PDAC), a metabolic disorder, remains one of the leading cancer mortality sources worldwide. An initial response to treatments, such as gemcitabine (GEM), is often followed by emergent resistance reflecting an urgent need for alternate therapies. The PDAC resistance to GEM could be due to ERK1/2 activity. However, successful ERKi therapy is hindered due to low ligand efficiency, poor drug delivery, and toxicity. In this study, to overcome these limitations, we have designed pH-responsive nanoparticles (pHNPs) with a size range of 100-150 nm for the simultaneous delivery of ERKi (SCH 772984) and GEM with tolerable doses. These pHNPs are polyethylene glycol (PEG)-containing amphiphilic polycarbonate block copolymers with tertiary amine side chains. They are systemically stable and capable of improving in vitro and in vivo drug delivery at the cellular environment's acidic pH. The functional analysis indicates that the nanomolar doses of ERKi or GEM significantly decreased the 50% growth inhibition (IC50) of PDAC cells when encapsulated in pHNPs compared to free drugs. The combination of ERKi with GEM displayed a synergistic inhibitory effect. Unexpectedly, we uncover that the minimum effective dose of ERKi significantly promotes GEM activities on PDAC cells. Furthermore, we found that pHNP-encapsulated combination therapy of ERKi with GEM was superior to unencapsulated combination drug therapy. Our findings, thus, reveal a simple, yet efficient, drug delivery approach to overcome the limitations of ERKi for clinical applications and present a new model of sensitization of GEM by ERKi with no or minimal toxicity.


Assuntos
Proliferação de Células/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Portadores de Fármacos/química , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nanopartículas/química , Neoplasias Pancreáticas/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Carcinoma Ductal Pancreático/tratamento farmacológico , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Desoxicitidina/química , Sistemas de Liberação de Medicamentos/métodos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Camundongos , Camundongos Nus , Polietilenoglicóis/química , Polímeros/química , Inibidores de Proteínas Quinases/química , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Gencitabina
5.
Mol Pharm ; 17(8): 2849-2863, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32521162

RESUMO

In pancreatic ductal adenocarcinoma (PDAC), early onset of hypoxia triggers remodeling of the extracellular matrix, epithelial-to-mesenchymal transition, increased cell survival, the formation of cancer stem cells, and drug resistance. Hypoxia in PDAC is also associated with the development of collagen-rich, fibrous extracellular stroma (desmoplasia), resulting in severely impaired drug penetration. To overcome these daunting challenges, we created polymer nanoparticles (polymersomes) that target and penetrate pancreatic tumors, reach the hypoxic niches, undergo rapid structural destabilization, and release the encapsulated drugs. In vitro studies indicated a high cellular uptake of the polymersomes and increased cytotoxicity of the drugs under hypoxia compared to unencapsulated drugs. The polymersomes decreased tumor growth by nearly 250% and significantly increased necrosis within the tumors by 60% in mice compared to untreated controls. We anticipate that these polymer nanoparticles possess a considerable translational potential for delivering drugs to solid hypoxic tumors.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Hipóxia/tratamento farmacológico , Nanopartículas/química , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Carcinoma Ductal Pancreático/tratamento farmacológico , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/efeitos dos fármacos , Polímeros/química
6.
Mol Pharm ; 17(12): 4676-4690, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33151075

RESUMO

The molecular architecture of pH-responsive amphiphilic block copolymers, their self-assembly behavior to form nanoparticles (NPs), and doxorubicin (DOX)-loading technique govern the extent of DOX-induced cardiotoxicity. We observed that the choice of pH-sensitive tertiary amines, surface charge, and DOX-loading techniques within the self-assembled NPs strongly influence the release and stimulation of DOX-induced cardiotoxicity in primary cardiomyocytes. However, covalent conjugation of DOX to a pH-sensitive nanocarrier through a "conditionally unstable amide" linkage (PCPY-cDOX; PC = polycarbonate and PY = 2-pyrrolidine-1-yl-ethyl-amine) significantly reduced the cardiotoxicity of DOX in cardiomyocytes as compared to noncovalently encapsulated DOX NPs (PCPY-eDOX). When these formulations were tested for drug release in serum-containing media, the PCPY-cDOX systems showed prolonged control over drug release (for ∼72 h) at acidic pH compared to DOX-encapsulated nanocarriers, as expected. We found that DOX-encapsulated nanoformulations triggered cardiotoxicity in primary cardiomyocytes more acutely, while conjugated systems such as PCPY-cDOX prevented cardiotoxicity by disabling the nuclear entry of the drug. Using 2D and 3D (spheroid) cultures of an ER + breast cancer cell line (MCF-7) and a triple-negative breast cancer cell line (MDA-MB-231), we unravel that, similar to encapsulated systems (PCPY-eDOX-type) as reported earlier, the PCPY-cDOX system suppresses cellular proliferation in both cell lines and enhances trafficking through 3D spheroids of MDA-MB-231 cells. Collectively, our studies indicate that PCPY-cDOX is less cardiotoxic as compared to noncovalently encapsulated variants without compromising the chemotherapeutic properties of the drug. Thus, our studies suggest that the appropriate selection of the nanocarrier for DOX delivery may prove fruitful in shifting the balance between low cardiotoxicity and triggering the chemotherapeutic potency of DOX.


Assuntos
Cardiotoxicidade/prevenção & controle , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Neoplasias/tratamento farmacológico , Polímeros/química , Animais , Animais Recém-Nascidos , Cardiotoxicidade/etiologia , Linhagem Celular Tumoral , Doxorrubicina/farmacocinética , Doxorrubicina/toxicidade , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração de Íons de Hidrogênio , Miócitos Cardíacos , Nanopartículas/química , Neoplasias/patologia , Cimento de Policarboxilato , Cultura Primária de Células , Pirrolidinas/química , Ratos , Esferoides Celulares , Testes de Toxicidade Aguda
7.
Molecules ; 23(6)2018 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-29861466

RESUMO

Hyperbranched polyglycerol (hPG) has been used as a multivalent scaffold to develop a series of nanocarriers capable of high-affinity encapsulation of copper (Cu). A rationally selected set of Cu-complexing motifs has been conjugated to hPG hydroxyl groups to render the constructs potentially usable as exogenous sources of Cu for addressing different pathological conditions associated with Cu-deficiency. We have utilized a newly discovered route to attach Cu-binding domains exclusively within a hPG core by selective differentiation between the primary and secondary hydroxyl groups of the polyol. These hPG-derivatives were found to form a stable complex with Cu ions depending on the type of immobilized ligands and corresponding degree of functionalization. In addition, these Cu-bearing nano-complexes demonstrated moderately cationic surface charge resulting in adjustable protein-binding characteristics and low cellular toxicity profile. We envision that these Cu-loaded hPG nanocarriers can be used as a stable platform to transport the metal ion across the systemic circulation to supply bioavailable quantity of Cu in disease-afflicted tissues.


Assuntos
Cobre/química , Portadores de Fármacos/química , Glicerol/química , Nanopartículas/química , Polímeros/química , Amidas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Transporte de Íons , Íons/química , Espectroscopia de Ressonância Magnética , Nanoestruturas/química , Oligossacarídeos/química , Albumina Sérica/química , Termodinâmica
8.
Nanomedicine ; 13(5): 1797-1808, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28263813

RESUMO

A ligand decorated, synthetic polypeptide block copolymer platform with environment-responsive capabilities was designed. We evaluated the potential of this system to function as a polymersome for targeted-delivery of a systemic chemotherapy to tumors. Our system employed click chemistry to provide a pH-responsive polypeptide block that drives nanoparticle assembly, and a ligand (folic acid) conjugated PEG block that targets folate-receptor over-expressing cancer cells. These nanocarriers were found to encapsulate a high loading of conventional chemotherapeutics (e.g. doxorubicin at physiological pH) and release the active therapeutic at lysosomal pH upon cellular uptake. The presence of folic acid on the nanoparticle surface facilitated their active accumulation in folate-receptor-overexpressing cancer cells (KB), compared to untargeted carriers. Folate-targeted nanoparticles loaded with doxorubicin also showed enhanced tumor accumulation in folate-receptor positive KB xenografts, resulting in the suppression of tumor growth in an in vivo hind flank xenograft mouse model.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Nanopartículas , Peptídeos , Animais , Linhagem Celular Tumoral , Portadores de Fármacos , Ácido Fólico , Humanos , Camundongos , Polímeros
9.
Proc Natl Acad Sci U S A ; 111(35): 12847-52, 2014 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-25136093

RESUMO

Traumatic wounds and congenital defects that require large-scale bone tissue repair have few successful clinical therapies, particularly for craniomaxillofacial defects. Although bioactive materials have demonstrated alternative approaches to tissue repair, an optimized materials system for reproducible, safe, and targeted repair remains elusive. We hypothesized that controlled, rapid bone formation in large, critical-size defects could be induced by simultaneously delivering multiple biological growth factors to the site of the wound. Here, we report an approach for bone repair using a polyelectrolye multilayer coating carrying as little as 200 ng of bone morphogenetic protein-2 and platelet-derived growth factor-BB that were eluted over readily adapted time scales to induce rapid bone repair. Based on electrostatic interactions between the polymer multilayers and growth factors alone, we sustained mitogenic and osteogenic signals with these growth factors in an easily tunable and controlled manner to direct endogenous cell function. To prove the role of this adaptive release system, we applied the polyelectrolyte coating on a well-studied biodegradable poly(lactic-co-glycolic acid) support membrane. The released growth factors directed cellular processes to induce bone repair in a critical-size rat calvaria model. The released growth factors promoted local bone formation that bridged a critical-size defect in the calvaria as early as 2 wk after implantation. Mature, mechanically competent bone regenerated the native calvaria form. Such an approach could be clinically useful and has significant benefits as a synthetic, off-the-shelf, cell-free option for bone tissue repair and restoration.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Regeneração Óssea/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-sis/farmacologia , Medicina Regenerativa/métodos , Crânio/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Alendronato/farmacologia , Indutores da Angiogênese/farmacologia , Animais , Becaplermina , Materiais Biocompatíveis/farmacologia , Conservadores da Densidade Óssea/farmacologia , Osso e Ossos/efeitos dos fármacos , Modelos Animais de Doenças , Ácido Láctico/farmacologia , Masculino , Membranas Artificiais , Ácido Poliglicólico/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Sprague-Dawley , Crânio/lesões
10.
Adv Funct Mater ; 26(7): 991-1003, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-27134622

RESUMO

Layer-by-layer (LbL) self-assembly is a versatile technique from which multicomponent and stimuli-responsive nanoscale drug carriers can be constructed. Despite the benefits of LbL assembly, the conventional synthetic approach for fabricating LbL nanoparticles requires numerous purification steps that limit scale, yield, efficiency, and potential for clinical translation. In this report, we describe a generalizable method for increasing throughput with LbL assembly by using highly scalable, closed-loop diafiltration to manage intermediate purification steps. This method facilitates highly controlled fabrication of diverse nanoscale LbL formulations smaller than 150 nm composed from solid-polymer, mesoporous silica, and liposomal vesicles. The technique allows for the deposition of a broad range of polyelectrolytes that included native polysaccharides, linear polypeptides, and synthetic polymers. We also explore the cytotoxicity, shelf life and long-term storage of LbL nanoparticles produced using this approach. We find that LbL coated systems can be reliably and rapidly produced: specifically, LbL-modified liposomes could be lyophilized, stored at room temperature, and reconstituted without compromising drug encapsulation or particle stability, thereby facilitating large scale applications. Overall, this report describes an accessible approach that significantly improves the throughput of nanoscale LbL drug-carriers that show low toxicity and are amenable to clinically relevant storage conditions.

11.
Mol Pharm ; 11(7): 2420-30, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24813025

RESUMO

Herein we report the potential of click chemistry-modified polypeptide-based block copolymers for the facile fabrication of pH-sensitive nanoscale drug delivery systems. PEG-polypeptide copolymers with pendant amine chains were synthesized by combining N-carboxyanhydride-based ring-opening polymerization with post-functionalization using azide-alkyne cycloaddition. The synthesized block copolymers contain a polypeptide block with amine-functional side groups and were found to self-assemble into stable polymersomes and disassemble in a pH-responsive manner under a range of biologically relevant conditions. The self-assembly of these block copolymers yields nanometer-scale vesicular structures that are able to encapsulate hydrophilic cytotoxic agents like doxorubicin at physiological pH but that fall apart spontaneously at endosomal pH levels after cellular uptake. When drug-encapsulated copolymer assemblies were delivered systemically, significant levels of tumor accumulation were achieved, with efficacy against the triple-negative breast cancer cell line, MDA-MB-468, and suppression of tumor growth in an in vivo mouse model.


Assuntos
Portadores de Fármacos/química , Endossomos/química , Nanopartículas/química , Peptídeos/química , Polietilenoglicóis/química , Polímeros/química , Animais , Linhagem Celular Tumoral , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Endogâmicos BALB C , Polimerização , Solubilidade
12.
Biomacromolecules ; 15(5): 1910-9, 2014 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-24725062

RESUMO

Copper (Cu) is a cofactor of various metalloenzymes and has a role in neurodegenerative diseases with disturbed Cu homeostasis, for example, in Alzheimer's disease (AD) and Menkes disease. To address Cu imbalances, we synthesized two different dendritic nanoparticles (NP) for the transport of Cu(II) ions across the blood-brain barrier (BBB). The synthesized NPs show low toxicity and high water solubility and can stabilize high amounts of Cu(II). The Cu(II)-laden NPs crossed cellular membranes and increased the cellular Cu level. A human brain microvascular endothelial cell (HBMEC) model was established to investigate the permeability of the NPs through the BBB. By comparing the permeability × surface area product (PSe) of reference substances with those of NPs, we observed that NPs crossed the BBB model two times more effectively than (14)C-sucrose and sodium fluorescein (NaFl) and up to 60× better than Evans Blue labeled albumin (EBA). Our results clearly indicate that NPs cross the BBB model effectively. Furthermore, Cu was shielded by the NPs, which decreased the Cu toxicity. The novel design of the core-shell NP enabled the complexation of Cu(II) in the outer shell and therefore facilitated the pH-dependent release of Cu in contrast to core-multishell NPs, where the Cu(II) ions are encapsulated in the core. This allows a release of Cu into the cytoplasm. In addition, by using a cellular detection system based on a metal response element with green fluorescent protein (MRE-GFP), we demonstrated that Cu could also be released intracellularly from NPs and is accessible for biological processes. Our results indicate that NPs are potential candidates to rebalance metal-ion homeostasis in disease conditions affecting brain and neuronal systems.


Assuntos
Barreira Hematoencefálica/metabolismo , Cobre/metabolismo , Portadores de Fármacos/metabolismo , Modelos Biológicos , Nanopartículas/metabolismo , Transporte Biológico , Células da Medula Óssea/química , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cobre/administração & dosagem , Cobre/farmacologia , Relação Dose-Resposta a Droga , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Células Endoteliais/química , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Nanopartículas/administração & dosagem , Nanopartículas/química , Relação Estrutura-Atividade
13.
ACS Appl Mater Interfaces ; 16(12): 14405-14420, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38490971

RESUMO

Developing protein confinement platforms is an attractive research area that not only promotes protein delivery but also can result in artificial environment mimicking of the cellular one, impacting both the controlled release of proteins and the fundamental protein biophysics. Polymeric nanoparticles (PNPs) are attractive platforms to confine proteins due to their superior biocompatibility, low cytotoxicity, and controllable release under external stimuli. However, loading proteins into PNPs can be challenging due to the potential protein structural perturbation upon contacting the interior of PNPs. In this work, we developed a novel approach to encapsulate proteins in PNPs with the assistance of the zeolitic imidazolate framework (ZIF). Here, ZIF offers an additional protection layer to the target protein by forming the protein@ZIF composite via aqueous-phase cocrystallization. We demonstrated our platform using a model protein, lysozyme, and a widely studied PNP composed of poly(ethylene glycol)-poly(lactic-co-glycolic acid) (PEG-PLGA). A comprehensive study via standard loading and release tests as well as various spectroscopic techniques was carried out on lysozyme loaded onto PEG-PLGA with and without ZIF protection. As compared with the direct protein encapsulation, an additional layer with ZIF prior to loading offered enhanced loading capacity, reduced leaching, especially in the initial stage, led to slower release kinetics, and reduced secondary structural perturbation. Meanwhile, the function, cytotoxicity, and cellular uptake of proteins encapsulated within the ZIF-bound systems are decent. Our results demonstrated the use of ZIF in assisting in protein encapsulation in PNPs and established the basis for developing more sophisticated protein encapsulation platforms using a combination of materials of diverse molecular architectures and disciplines. As such, we anticipate that the protein-encapsulated ZIF systems will serve as future polymer protein confinement and delivery platforms for both fundamental biophysics and biochemistry research and biomedical applications where protein delivery is needed to support therapeutics and/or nutrients.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Poliésteres , Polietilenoglicóis , Zeolitas , Estruturas Metalorgânicas/química , Muramidase , Nanopartículas/química , Polímeros , Zeolitas/química
14.
Cells ; 13(5)2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38474359

RESUMO

The aberrant glycosylation is a hallmark of cancer progression and chemoresistance. It is also an immune therapeutic target for various cancers. Tunicamycin (TM) is one of the potent nucleoside antibiotics and an inhibitor of aberrant glycosylation in various cancer cells, including breast cancer, gastric cancer, and pancreatic cancer, parallel with the inhibition of cancer cell growth and progression of tumors. Like chemotherapies such as doxorubicin (DOX), 5'fluorouracil, etoposide, and cisplatin, TM induces the unfolded protein response (UPR) by blocking aberrant glycosylation. Consequently, stress is induced in the endoplasmic reticulum (ER) that promotes apoptosis. TM can thus be considered a potent antitumor drug in various cancers and may promote chemosensitivity. However, its lack of cell-type-specific cytotoxicity impedes its anticancer efficacy. In this review, we focus on recent advances in our understanding of the benefits and pitfalls of TM therapies in various cancers, including breast, colon, and pancreatic cancers, and discuss the mechanisms identified by which TM functions. Finally, we discuss the potential use of nano-based drug delivery systems to overcome non-specific toxicity and enhance the therapeutic efficacy of TM as a targeted therapy.


Assuntos
Neoplasias da Mama , Estresse do Retículo Endoplasmático , Humanos , Feminino , Tunicamicina/farmacologia , Linhagem Celular Tumoral , Glicosilação , Neoplasias da Mama/patologia
15.
bioRxiv ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38586020

RESUMO

Self-assembled materials capable of modulating their assembly properties in response to specific enzymes play a pivotal role in advancing 'intelligent' encapsulation platforms for biotechnological applications. Here, we introduce a previously unreported class of synthetic nanomaterials that programmatically interact with histone deacetylase (HDAC) as the triggering stimulus for disassembly. These nanomaterials consist of co-polypeptides comprising poly (acetyl L-lysine) and poly(ethylene glycol) blocks. Under neutral pH conditions, they self-assemble into particles. However, their stability is compromised upon exposure to HDACs, depending on enzyme concentration and exposure time. Our investigation, utilizing HDAC8 as the model enzyme, revealed that the primary mechanism behind disassembly involves a decrease in amphiphilicity within the block copolymer due to the deacetylation of lysine residues within the particles' hydrophobic domains. To elucidate the response mechanism, we encapsulated a fluorescent dye within these nanoparticles. Upon incubation with HDAC, the nanoparticle structure collapsed, leading to controlled release of the dye over time. Notably, this release was not triggered by denatured HDAC8, other proteolytic enzymes like trypsin, or the co-presence of HDAC8 and its inhibitor. We further demonstrated the biocompatibility and cellular effects of these materials and conducted a comprehensive computational study to unveil the possible interaction mechanism between enzymes and particles. By drawing parallels to the mechanism of naturally occurring histone proteins, this research represents a pioneering step toward developing functional materials capable of harnessing the activity of epigenetic enzymes such as HDACs.

16.
PLoS One ; 19(4): e0297749, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38687749

RESUMO

Therapeutic options for managing Pancreatic ductal adenocarcinoma (PDAC), one of the deadliest types of aggressive malignancies, are limited and disappointing. Therefore, despite suboptimal clinical effects, gemcitabine (GEM) remains the first-line chemotherapeutic drug in the clinic for PDAC treatment. The therapeutic limitations of GEM are primarily due to poor bioavailability and the development of chemoresistance resulting from the addiction of mutant-K-RAS/AKT/ERK signaling-mediated desmoplastic barriers with a hypoxic microenvironment. Several new therapeutic approaches, including nanoparticle-assisted drug delivery, are being investigated by us and others. This study used pH-responsive nanoparticles encapsulated ERK inhibitor (SCH772984) and surface functionalized with tumor-penetrating peptide, iRGD, to target PDAC tumors. We used a small molecule, SCH772984, to target ERK1 and ERK2 in PDAC and other cancer cells. This nanocarrier efficiently released ERKi in hypoxic and low-pH environments. We also found that the free-GEM, which is functionally weak when combined with nanoencapsulated ERKi, led to significant synergistic treatment outcomes in vitro and in vivo. In particular, the combination approaches significantly enhanced the GEM effect in PDAC growth inhibition and prolonged survival of the animals in a genetically engineered KPC (LSL-KrasG12D/+/LSL-Trp53R172H/+/Pdx-1-Cre) pancreatic cancer mouse model, which is not observed in a single therapy. Mechanistically, we anticipate that the GEM efficacy was increased as ERKi blocks desmoplasia by impairing the production of desmoplastic regulatory factors in PDAC cells and KPC mouse tumors. Therefore, 2nd generation ERKi (SCH 772984)-iRGD-pHNPs are vital for the cellular response to GEM and denote a promising therapeutic target in PDAC with mutant K-RAS.


Assuntos
Desoxicitidina , Gencitabina , Nanopartículas , Neoplasias Pancreáticas , Animais , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Camundongos , Humanos , Linhagem Celular Tumoral , Nanopartículas/química , Concentração de Íons de Hidrogênio , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Mutação , Inibidores de Proteínas Quinases/farmacologia , Modelos Animais de Doenças , Microambiente Tumoral/efeitos dos fármacos
17.
J Mater Chem B ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39021201

RESUMO

Self-assembled materials capable of modulating their assembly properties in response to specific enzymes play a pivotal role in advancing 'intelligent' encapsulation platforms for biotechnological applications. Here, we introduce a previously unreported class of synthetic nanomaterials that programmatically interact with histone deacetylase (HDAC) as the triggering stimulus for disassembly. These nanomaterials consist of co-polypeptides comprising poly(acetyl L-lysine) and poly(ethylene glycol) blocks. Under neutral pH conditions, they self-assemble into particles. The hydrodynamic diameters of particles were typically withing the range of 108-190 nm, depending on degree of acetylation of the hydrophobic block. However, their stability is compromised upon exposure to HDACs, depending on enzyme concentration and exposure time. Our investigation, utilizing HDAC8 as the model enzyme, revealed that the primary mechanism behind disassembly involves a decrease in amphiphilicity within the block copolymer due to the deacetylation of lysine residues within the particles' hydrophobic domains. To elucidate the response mechanism, we encapsulated a fluorescent dye within these nanoparticles. Upon incubation with HDAC, the nanoparticle structure collapsed, leading to controlled release of the dye over time. Notably, this release was not triggered by denatured HDAC8, other proteolytic enzymes like trypsin, or the co-presence of HDAC8 and its inhibitor. We also demonstrated the biocompatibility and cellular effects of these materials in the context of drug delivery in different types of anticancer cell lines, such as MIA PaCa-2, PANC-1, cancer like stem cells (CSCs), and non-cancerous HPNE cells. We observed that the release of a model drug (such as a STAT3 pathway inhibitor, Napabucasin) can be loaded into these nanoparticles, with >90% of the dosage can be released over 3 h under the influence of HDAC8 enzyme in a controlled fashion. Further, we conducted a comprehensive computational study to unveil the possible interaction mechanism between enzymes and particles. By drawing parallels to the mechanism of naturally occurring histone proteins, this research represents a pioneering step toward developing functional materials capable of harnessing the activity of epigenetic enzymes such as HDACs.

18.
J Cell Commun Signal ; 17(1): 35-45, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35674933

RESUMO

The Cellular communication network (CCN) family of growth regulatory factors comprises six secreted matricellular proteins that promote signal transduction through cell-cell or cell-matrix interaction. The diversity of functionality between each protein is specific to the many aspects of healthy and cancer biology. For example, CCN family proteins modulate cell adhesion, proliferation, migration, invasiveness, apoptosis, and survival. In addition, the expression of each protein regulates many biological and pathobiological processes within its microenvironment to regulate angiogenesis, inflammatory response, chondrogenesis, fibrosis, and mitochondrial integrity. The collective range of CCN operation remains fully comprehended; however, understanding each protein's microenvironment may draw more conclusions about the abundance of interactions and signaling cascades occurring within such issues. This review observes and distinguishes the various roles a CCN protein may execute within distinct tumor microenvironments and the biological associations among them. Finally. We also review how CCN-family proteins can be used in nano-based therapeutic implications.

19.
ACS Appl Bio Mater ; 6(7): 2698-2711, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37405899

RESUMO

In this report, two polymeric matrix systems at macro and nanoscales were prepared for efficacious fungicide delivery. The macroscale delivery systems used millimeter-scale, spherical beads composed of cellulose nanocrystals and poly(lactic acid). The nanoscale delivery system involved micelle-type nanoparticles, composed of methoxylated sucrose soyate polyols. Sclerotinia sclerotiorum (Lib.), a destructive fungus affecting high-value industrial crops, was used as a model pathogen against which the efficacy of these polymeric formulations was demonstrated. Commercial fungicides are applied on plants frequently to overcome the transmission of fungal infection. However, fungicides alone do not persist on the plants for a prolonged period due to environmental factors such as rain and airflow. There is a need to apply fungicides multiple times. As such, standard application practices generate a significant environmental footprint due to fungicide accumulation in soil and runoff in surface water. Thus, approaches are needed that can either increase the efficacy of commercially active fungicides or prolong their residence time on plants for sustained antifungal coverage. Using azoxystrobin (AZ) as a model fungicide and canola as a model crop host, we hypothesized that the AZ-loaded macroscale beads, when placed in contact with plants, will act as a depot to release the fungicide at a controlled rate to protect plants against fungal infection. The nanoparticle-based fungicide delivery approach, on the other hand, can be realized via spray or foliar applications. The release rate of AZ from macro- and nanoscale systems was evaluated and analyzed using different kinetic models to understand the mechanism of AZ delivery. We observed that, for macroscopic beads, porosity, tortuosity, and surface roughness governed the efficiency of AZ delivery, and for nanoparticles, contact angle and surface adhesion energy were directing the efficacy of the encapsulated fungicide. The technology reported here can also be translated to a wide variety of industrial crops for fungal protection. The strength of this study is the possibility of using completely plant-derived, biodegradable/compostable additive materials for controlled agrochemical delivery formulations, which will contribute to reducing the frequency of fungicide applications and the potential accumulation of formulation components in soil and water.


Assuntos
Fungicidas Industriais , Micoses , Fungicidas Industriais/química , Estrobilurinas , Solo , Produtos Agrícolas
20.
Polymers (Basel) ; 16(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38201701

RESUMO

The widely used high-density polyethylene (HDPE) polymer has inadequate mechanical and thermal properties for structural applications. To overcome this challenge, nano zinc oxide (ZnO) and nano boron oxide (B2O3) doped lignin-containing cellulose nanocrystals (L-CNC) were blended in the polymer matrix. The working hypothesis is that lignin will prevent CNC aggregation, and metal oxides will reduce the flammability of polymers by modifying their degradation pathways. This research prepared and incorporated safe, effective, and eco-friendly hybrid systems of nano ZnO/L-CNC and nano B2O3/L-CNC into the HDPE matrix to improve their physio-mechanical and fire-retardant properties. The composites were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis, thermo-gravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis, horizontal burning test, and microcalorimetry test. The results demonstrated a substantial increase in mechanical properties and a reduction in flammability. The scanning electron microscope (SEM) images showed some agglomeration and irregular distribution of the inorganic oxides.

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