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1.
Biol Direct ; 19(1): 30, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654256

RESUMO

BACKGROUND: Large bone defects pose a clinical treatment challenge; inhibiting transferrin receptor 2 (TfR2), which is involved in iron metabolism, can promote osteogenesis. Iron-based metal-organic frameworks (MOF-Fe) particles not only inhibit TfR2 but also serve as biomimetic catalysts to remove hydrogen peroxide in reactive oxygen species (ROS); excess ROS can disrupt the normal functions of osteoblasts, thereby hindering bone regeneration. This study explored the potential effects of MOF-Fe in increasing osteogenic activity and clearing ROS. METHODS: In vitro experiments were performed to investigate the osteogenic effects of MOF-Fe particles and assess their impact on cellular ROS levels. To further validate the role of MOF-Fe in promoting bone defect repair, we injected MOF-Fe suspensions into the femoral defects of SD rats and implanted MOF-Fe-containing hydrogel scaffolds in rabbit cranial defect models and observed their effects on bone healing. RESULTS: In vitro, the presence of MOF-Fe significantly increased the expression levels of osteogenesis-related genes and proteins compared to those in the control group. Additionally, compared to those in the untreated control group, the cells treated with MOF-Fe exhibited a significantly increased ability to remove hydrogen peroxide from ROS and generate oxygen and water within the physiological pH range. In vivo experiments further confirmed the positive effect of MOF-Fe in promoting bone defect repair. CONCLUSION: This study supports the application of MOF-Fe as an agent for bone regeneration, particularly for mitigating ROS and activating the bone morphogenetic protein (BMP) pathway, demonstrating its potential value.


Assuntos
Proteína Morfogenética Óssea 2 , Regeneração Óssea , Osteogênese , Ratos Sprague-Dawley , Animais , Proteína Morfogenética Óssea 2/metabolismo , Proteína Morfogenética Óssea 2/genética , Ratos , Regeneração Óssea/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Coelhos , Estruturas Metalorgânicas/química , Receptores da Transferrina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peroxidase/metabolismo , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Peróxido de Hidrogênio , Masculino
2.
Mater Horiz ; 11(8): 1944-1956, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38345779

RESUMO

To date, the reported injectable hydrogels have failed to mimic the fibrous architecture of the extracellular matrix (ECM), limiting their biological effects on cell growth and phenotype. Additionally, they lack the micro-sized pores present within the ECM, which is unfavorable for the facile transport of nutrients and waste. Herein, an injectable ECM-mimetic hydrogel (IEMH) was fabricated by shortening and dispersing Janus fibers capable of self-curling at body temperature into pH 7.4 phosphate buffer solution. The IEMH could be massively prepared through a side-by-side electrospinning process combined with ultraviolet irradiation. The IEMHs with only 5 wt% fibers could undergo sol-gel transition at body temperature to become solid gels with desirable stability, sturdiness, and elasticity and self-healing ability. In addition, they possessed notable pseudoplasticity, which is beneficial to injection at room temperature. The results obtained from characterization analysis via scanning electron microscopy, total internal reflection fluorescence microscopy, nuclear magnetic resonance spectroscopy, and Fourier-transform infrared spectroscopy indicate that their sol-gel transition under physiological conditions stems from the synergistic action of the tight entanglements between thermally-induced self-curling fibers and the hydrophobic interaction between the fibers. An MTT assay using C2C12 myoblast cells was performed to examine the in vitro cytotoxicity of IEMHs for biomedical applications, and the cell viability was found to be more than 95%.


Assuntos
Matriz Extracelular , Hidrogéis , Matriz Extracelular/química , Hidrogéis/química , Hidrogéis/farmacologia , Animais , Camundongos , Linhagem Celular , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
3.
Int J Biol Macromol ; 260(Pt 2): 129514, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38237825

RESUMO

Electrospun biomimetic materials based on polyester of natural origin poly-3-hudroxybutyrate (PHB) modified with hemin (Hmi) and fibrinogen (Fbg) represent a great interest and are potentially applicable in various fields. Here, we describe formulation of the new fibrous PHB-Fbg and PHB-Hmi-Fbg materials with complex structure for biomedical application. The average diameter of the fibers was 3.5 µm and 1.8 µm respectively. Hmi presence increased porosity from 80 % to 94 %, significantly reduced the number of defects, ensured the formation of a larger number of open pores, and improved mechanical properties. Hmi presence significantly improved the molding properties of the material. Hmi facilitated effective Fbg adsorption on the of the PHB wound-healing material, ensuring uniform localization of the protein on the surface of the fibers. Next, we evaluated cytocompatibility, cell behavior, and open wound healing in mice. The results demonstrated that PHB-Fbg and PHB-Hmi-Fbg electrospun materials had pronounced properties and may be promising for early-stage wound healing - the PHB-Hmi-Fbg sample accelerated wound closure by 35 % on the 3rd day, and PHB-Hmi showed 45 % more effective wound closure on the 15th day.


Assuntos
Materiais Biomiméticos , Hemostáticos , Camundongos , Animais , Fibrinogênio , Cicatrização , Materiais Biomiméticos/farmacologia , Poliésteres/química
4.
Antiviral Res ; 217: 105673, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37478917

RESUMO

Human cytomegalovirus (HCMV) can cause serious diseases in immunocompromised patients. Use of current antivirals is limited by their adverse effects and emergence of drug resistance mutations. Thus, new drugs are an urgent need. The terminase complex (pUL56-pUL89-pUL51) represents a target of choice for new antivirals development. pUL51 was shown to be crucial for the cleavage of concatemeric HCMV DNA and viral replication. Its C-terminal part plays a critical role for the terminase complex assembly. However, no interaction domain is clearly identified. Sequence comparison of herpesvirus homologs and protein modelling were performed on pUL51. Importance of a putative interaction domain is validated by the generation of recombinant viruses with specific alanine substitutions of amino acids implicated in the domain. We identified a Leucine-Zipper (LZ) domain involving the leucine residues L126-X6-L133-X6-L140-X6-L147 in C-terminal part of pUL51. These leucines are crucial for viral replication, suggesting the significance for pUL51 structure and function. A mimetic-peptide approach has been used and tested in antiviral assays to validate the interaction domain as a new therapeutic target. Cytotoxicity was evaluated by LDH release measurement. The peptide TAT-HK29, homologous to the pUL51-LZ domain, inhibits HCMV replication by 27% ± 9% at 1.25 µM concentration without cytotoxicity. Our results highlight the importance of a leucine zipper domain in the C-terminal part of pUL51 involving leucines L126, L133, L140 and L147. We also confirm the potential of mimetic peptides to inhibit HCMV replication and the importance to target interaction domains to develop antiviral agents.


Assuntos
Antivirais , Materiais Biomiméticos , Citomegalovirus , Endodesoxirribonucleases , Zíper de Leucina , Proteínas Virais , Replicação Viral , Replicação Viral/efeitos dos fármacos , Citomegalovirus/efeitos dos fármacos , Antivirais/química , Antivirais/farmacologia , Proteínas Virais/antagonistas & inibidores , Proteínas Virais/química , Proteínas Virais/genética , Desenvolvimento de Medicamentos , Endodesoxirribonucleases/antagonistas & inibidores , Endodesoxirribonucleases/química , Humanos , Peptídeos/química , Peptídeos/farmacologia , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia
5.
Arterioscler Thromb Vasc Biol ; 43(8): e291-e302, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37317849

RESUMO

The ECM (extracellular matrix) is a 3-dimensional network that supports cellular responses and maintains structural tissue integrity in healthy and pathological conditions. The interactions between ECM and cells trigger signaling cascades that lead to phenotypic changes and structural and compositional turnover of the ECM, which in turn regulates vascular cell behavior. Hydrogel biomaterials are a powerful platform for basic and translational studies and clinical applications due to their high swelling capacity and exceptional versatility in compositions and properties. This review highlights recent developments and uses of engineered natural hydrogel platforms that mimic the ECM and present defined biochemical and mechanical cues for vascularization. Specifically, we focus on modulating vascular cell stimulation and cell-ECM/cell-cell interactions in the microvasculature that are the established biomimetic microenvironment.


Assuntos
Materiais Biomiméticos , Matriz Extracelular , Hidrogéis , Microvasos , Neovascularização Fisiológica , Engenharia Tecidual , Hidrogéis/química , Hidrogéis/farmacologia , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/fisiologia , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Fisiológica/genética , Neovascularização Fisiológica/fisiologia , Microvasos/efeitos dos fármacos , Microvasos/fisiologia , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Humanos , Engenharia Tecidual/métodos , Tecidos Suporte , Técnicas de Transferência de Genes , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Animais
6.
Curr Top Med Chem ; 23(10): 907-920, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37102484

RESUMO

Due to their unique biological functionality, nanocarriers can be designed to deliver various anti-tumor drugs in vivo, which has a wide and important application prospect in the field of tumor therapy. However, poor biosafety, short blood circulation time, and weak targeting ability still limit the application of nanoparticles in tumor therapy. In recent years, with the development of biomedicine, the biomimetic technology-based biomembrane-mediated drug delivery system is expected to achieve a breakthrough in tumor-targeted therapy due to low immunogenicity, tumor targeting, the adjustability and versatility of intelligent nanocarrier design. This paper mainly reviews the research process of different types of the cell membrane (erythrocyte membrane, cancer cell membrane, bacterial membrane, stem cell membrane, and hybrid membrane)-camouflaged nanoparticles in tumor therapy, as well as the challenges and development prospects in clinical application.


Assuntos
Antineoplásicos , Materiais Biomiméticos , Nanopartículas , Neoplasias , Humanos , Biomimética , Materiais Biomiméticos/farmacologia , Membrana Celular , Membrana Eritrocítica/patologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias/patologia , Sistemas de Liberação de Medicamentos , Nanopartículas/uso terapêutico
7.
Mil Med Res ; 10(1): 16, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36978167

RESUMO

Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering (TE) and regenerative medicine. In contrast to conventional biomaterials or synthetic materials, biomimetic scaffolds based on natural biomaterial can offer cells a broad spectrum of biochemical and biophysical cues that mimic the in vivo extracellular matrix (ECM). Additionally, such materials have mechanical adaptability, microstructure interconnectivity, and inherent bioactivity, making them ideal for the design of living implants for specific applications in TE and regenerative medicine. This paper provides an overview for recent progress of biomimetic natural biomaterials (BNBMs), including advances in their preparation, functionality, potential applications and future challenges. We highlight recent advances in the fabrication of BNBMs and outline general strategies for functionalizing and tailoring the BNBMs with various biological and physicochemical characteristics of native ECM. Moreover, we offer an overview of recent key advances in the functionalization and applications of versatile BNBMs for TE applications. Finally, we conclude by offering our perspective on open challenges and future developments in this rapidly-evolving field.


Assuntos
Materiais Biocompatíveis , Materiais Biomiméticos , Humanos , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Materiais Biocompatíveis/química , Engenharia Tecidual , Medicina Regenerativa , Biomimética , Materiais Biomiméticos/farmacologia , Materiais Biomiméticos/uso terapêutico , Materiais Biomiméticos/química
8.
ACS Biomater Sci Eng ; 9(4): 1757-1773, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-34870411

RESUMO

Biomineralization is a process in which natural organisms regulate the crystal growth of inorganic minerals, resulting in hierarchical structured biominerals with excellent properties. Typical biominerals in the human body are the bones and teeth, and damage to these hard tissues directly affect our daily lives. The repair of bones and teeth in a biomimetic way, either by using a biomimetic mineralization strategy or biomimetic materials, is the key for hard tissue regeneration. In this review, we briefly introduce the structure of bone and tooth, and highlight the fundamental role of collagen mineralization in tissue repair. The recent progress on intra-/extrafibrillar collagen mineralization by a biomimetic strategy or materials is presented, and their potential for tissue regeneration is discussed. Then, recent achievements on bone and tooth repair are summarized, and these works are discussed in the view of materials science and biological science, providing a broader vision for the future research of hard tissue repair techniques. Lastly, recent progress on hard tissue regeneration is concluded, and existing problems and future directions are prospected.


Assuntos
Materiais Biomiméticos , Dente , Humanos , Biomimética , Colágeno , Osso e Ossos , Materiais Biomiméticos/farmacologia , Materiais Biomiméticos/química
9.
Glycobiology ; 33(1): 17-37, 2023 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-36190502

RESUMO

O-linked ß-N-acetylglucosamine (O-GlcNAc)-modified proteins are post-translationally modified with GlcNAc conjugated to serine and threonine residues. This modification is associated with various physiological functions such as serine and threonine phosphorylation and Notch signaling. Here, we demonstrated that O-GlcNAc-modified proteins leaked from dead cells and GlcNAc-bearing polymers mimicking the multivalent GlcNAc moiety of these proteins induced anti-fibrotic activities, such as the suppression of α-smooth muscle actin and collagen and the induction of matrix metalloprotease 1 in myofibroblasts. We have previously reported that O-GlcNAc-modified proteins and GlcNAc-bearing polymers could interact with cell surface vimentin and desmin. In the current study, it was demonstrated that a multivalent GlcNAc moiety structure of these molecules activated PI3K/Akt and p38MAPK pathway and elicited these anti-fibrotic activities in myofibroblasts by interacting with cell surface vimentin. Since the interaction of O-GlcNAc-modified proteins with desmin was observed in the fibrotic liver of carbon tetrachloride-treated mice via an in situ proximity ligation assay, it was assumed that the activated stellate cells could bind to the O-GlcNAc-modified proteins from the damaged hepatocytes. In addition, the administration of anti-O-GlcNAc antibody to inhibit the interaction exacerbated liver fibrosis in the mice. Moreover, administration of the GlcNAc-bearing polymers into carbon tetrachloride-treated mice could ameliorate liver fibrosis. Thus, O-GlcNAc-modified proteins leaked from dead cells can interact with myofibroblasts and activated stellate cells and function as fibrosis suppressors. Moreover, we anticipate that GlcNAc-bearing polymers mimicking O-GlcNAc-modified proteins will be applied as novel therapeutic tools for fibrosis.


Assuntos
Acetilglucosamina , Miofibroblastos , Animais , Camundongos , Acetilglucosamina/metabolismo , Materiais Biomiméticos/farmacologia , Tetracloreto de Carbono , Desmina/metabolismo , Cirrose Hepática , Miofibroblastos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Polímeros/química , Polímeros/metabolismo , Processamento de Proteína Pós-Traducional , Serina/metabolismo , Vimentina/química , Vimentina/metabolismo , Células Estreladas do Fígado/metabolismo
10.
J Nanobiotechnology ; 20(1): 542, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575429

RESUMO

Synthetic nanoparticles with surface bioconjugation are promising platforms for targeted therapy, but their simple biological functionalization is still a challenging task against the complex intercellular environment. Once synthetic nanoparticles enter the body, they are phagocytosed by immune cells by the immune system. Recently, the cell membrane camouflage strategy has emerged as a novel therapeutic tactic to overcome these issues by utilizing the fundamental properties of natural cells. Macrophage, a type of immune system cells, plays critical roles in various diseases, including cancer, atherosclerosis, rheumatoid arthritis, infection and inflammation, due to the recognition and engulfment function of removing substances and pathogens. Macrophage membranes inherit the surface protein profiles and biointerfacing properties of source cells. Therefore, the macrophage membrane cloaking can protect synthetic nanoparticles from phagocytosis by the immune cells. Meanwhile, the macrophage membrane can make use of the natural correspondence to accurately recognize antigens and target inflamed tissue or tumor sites. In this review, we have summarized the advances in the fabrication, characterization and homing capacity of macrophage membrane cloaking nanoparticles in various diseases, including cancers, immune diseases, cardiovascular diseases, central nervous system diseases, and microbial infections. Although macrophage membrane-camouflaged nanoparticles are currently in the fetal stage of development, there is huge potential and challenge to explore the conversion mode in the clinic.


Assuntos
Materiais Biomiméticos , Nanopartículas , Neoplasias , Humanos , Biomimética , Membrana Celular/metabolismo , Macrófagos/patologia , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Nanopartículas/uso terapêutico , Materiais Biomiméticos/farmacologia
11.
Colloids Surf B Biointerfaces ; 219: 112803, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36084510

RESUMO

Cell membrane cloaking is an important biomimetic approach for improving drug residence time in the body due to its distinctive concealment ability, making it highly biocompatible and efficient for targeted drug delivery. Leukocytes are considered a fundamental part of the immune system. Leukocyte membrane cloaked nanoparticles offer site-specificity and can escape the opsonization process besides enhanced systemic circulation time. This review emphasizes the anatomical and physiological features of different leukocytes in addition to the preparation and characterization of leukocyte membrane cloaked nanoparticles. It also covers the recent advancements of this biointerfacing platform in cancer therapy, inflammatory disorders, multifunctional targeted therapy and hybrid membrane-coated nanoparticles. However, leukocytes are complex, nucleated cell structures and isolating their membranes poses a greater difficulty. Leukocyte membrane cloaking is an upcoming strategy in the infancy stage; nevertheless, there is immense scope to explore this biomimetic delivery system in terms of clinical transition, particularly for inflammatory diseases and cancer.


Assuntos
Materiais Biomiméticos , Nanopartículas , Neoplasias , Humanos , Biomimética , Materiais Biomiméticos/farmacologia , Materiais Biomiméticos/química , Membrana Celular/química , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Leucócitos
12.
J Biol Chem ; 298(10): 102417, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36037967

RESUMO

Γ-Crystallins play a major role in age-related lens transparency. Their destabilization by mutations and physical chemical insults are associated with cataract formation. Therefore, drugs that increase their stability should have anticataract properties. To this end, we screened 2560 Federal Drug Agency-approved drugs and natural compounds for their ability to suppress or worsen H2O2 and/or heat-mediated aggregation of bovine γ-crystallins. The top two drugs, closantel (C), an antihelminthic drug, and gambogic acid (G), a xanthonoid, attenuated thermal-induced protein unfolding and aggregation as shown by turbidimetry fluorescence spectroscopy dynamic light scattering and electron microscopy of human or mouse recombinant crystallins. Furthermore, binding studies using fluorescence inhibition and hydrophobic pocket-binding molecule bis-8-anilino-1-naphthalene sulfonic acid revealed static binding of C and G to hydrophobic sites with medium-to-low affinity. Molecular docking to HγD and other γ-crystallins revealed two binding sites, one in the "NC pocket" (residues 50-150) of HγD and one spanning the "NC tail" (residues 56-61 to 168-174 in the C-terminal domain). Multiple binding sites overlap with those of the protective mini αA-crystallin chaperone MAC peptide. Mechanistic studies using bis-8-anilino-1-naphthalene sulfonic acid as a proxy drug showed that it bound to MAC sites, improved Tm of both H2O2 oxidized and native human gamma D, and suppressed turbidity of oxidized HγD, most likely by trapping exposed hydrophobic sites. The extent to which these drugs act as α-crystallin mimetics and reduce cataract progression remains to be demonstrated. This study provides initial insights into binding properties of C and G to γ-crystallins.


Assuntos
Materiais Biomiméticos , Catarata , Cristalino , Chaperonas Moleculares , Agregação Patológica de Proteínas , Salicilanilidas , Xantonas , alfa-Cristalinas , gama-Cristalinas , Animais , Bovinos , Humanos , Camundongos , alfa-Cristalinas/metabolismo , Catarata/tratamento farmacológico , Catarata/prevenção & controle , Catarata/genética , gama-Cristalinas/metabolismo , Peróxido de Hidrogênio/metabolismo , Cristalino/metabolismo , Chaperonas Moleculares/metabolismo , Simulação de Acoplamento Molecular , Naftalenos/metabolismo , Ácidos Sulfônicos/metabolismo , Salicilanilidas/química , Salicilanilidas/farmacologia , Salicilanilidas/uso terapêutico , Xantonas/química , Xantonas/farmacologia , Xantonas/uso terapêutico , Agregação Patológica de Proteínas/tratamento farmacológico , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Materiais Biomiméticos/uso terapêutico
13.
Cell Metab ; 34(7): 978-990.e4, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35700738

RESUMO

Nonalcoholic steatohepatitis (NASH) is a liver disease associated with significant morbidity. Kupffer cells (KCs) produce endogenous miR-690 and, via exosome secretion, shuttle this miRNA to other liver cells, such as hepatocytes, recruited hepatic macrophages (RHMs), and hepatic stellate cells (HSCs). miR-690 directly inhibits fibrogenesis in HSCs, inflammation in RHMs, and de novo lipogenesis in hepatocytes. When an miR-690 mimic is administered to NASH mice in vivo, all the features of the NASH phenotype are robustly inhibited. During the development of NASH, KCs become miR-690 deficient, and miR-690 levels are markedly lower in mouse and human NASH livers than in controls. KC-specific KO of miR-690 promotes NASH pathogenesis. A primary target of miR-690 is NADK mRNA, and NADK levels are inversely proportional to the cellular miR-690 content. These studies show that KCs play a central role in the etiology of NASH and raise the possibility that miR-690 could emerge as a therapeutic for this condition.


Assuntos
Materiais Biomiméticos , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Animais , Materiais Biomiméticos/farmacologia , Fibrose , Células de Kupffer/patologia , Células de Kupffer/fisiologia , Cirrose Hepática/complicações , Cirrose Hepática/genética , Cirrose Hepática/terapia , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/terapia
14.
Macromol Biosci ; 22(9): e2200079, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35751428

RESUMO

Enzyme mimicry is a topic of considerable interest in the development of multifunctional biomimetic materials. Mimicking enzyme activity is a major challenge in biomaterials research, and artificial analogs that simultaneously recapitulate the catalytic and metabolic activity of native enzymes are considered to be the ultimate goal of this field. This consensus may be challenged by self-assembling multifunctional nanostructures to develop close-to-fidelity enzyme mimics. Here, the ability of fullerene nanostructures decorated with active units to form enzyme-like materials that can mimic phosphatases in a metal-free manner is presented. These nanostructures self-assemble into nanoclusters forming multiple random active sites that can cleave both phosphomonoesters and phosphodiesters while being more specific for the phosphomonoesters. Moreover, they are reusable and show an increase in catalytic activity over multiple cycles similar to their natural counterparts. In addition to having enzyme-like catalytic properties, these nanocatalysts imitate the biological functions of their natural analogs by inducing biomineralization and osteoinduction in preosteoblast and mesenchymal stem cells in vitro studies.


Assuntos
Materiais Biomiméticos , Fulerenos , Células-Tronco Mesenquimais , Nanoestruturas , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Fulerenos/farmacologia , Nanoestruturas/química , Osteogênese
15.
Mol Cancer Ther ; 21(6): 879-889, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35364607

RESUMO

MCL-1 is known to play a major role in resistance to BCL-2 inhibition, but the contribution of other BCL-2 family proteins has not been fully explored. We, here, demonstrate the ineffectiveness of MCL-1 inhibitor AMG176 in venetoclax-resistant, and conversely, of venetoclax in AMG176-resistant acute myelogenous leukemia (AML). Like cells with acquired resistance to venetoclax, cells with acquired resistance to AMG176 express increased MCL-1. Both cells with acquired resistance to venetoclax and to AMG176 express increased levels of BCL-2 and BCL-2A1, decreased BAX, and/or altered levels of other BCL-2 proteins. Cotargeting BCL-2 and MCL-1 was highly synergistic in AML cell lines with intrinsic or acquired resistance to BH3 mimetics or engineered to genetically overexpress BCL-2 or BCL-2A1 or downregulate BAX. The combination effectively eliminated primary AML blasts and stem/progenitor cells resistant to or relapsed after venetoclax-based therapy irrespective of mutations and cytogenetic abnormalities. Venetoclax and AMG176 combination markedly suppressed antiapoptotic BCL-2 proteins and AML stem/progenitor cells and dramatically extended mouse survival (median 336 vs. control 126 days; P < 0.0001) in a patient-derived xenograft (PDX) model developed from a venetoclax/hypomethylating agent therapy-resistant patient with AML. However, decreased BAX levels in the bone marrow residual leukemia cells after 4-week combination treatment may represent a resistance mechanism that contributed to their survival. Enhanced antileukemia activity was also observed in a PDX model of monocytic AML, known to be resistant to venetoclax therapy. Our results support codependence on multiple antiapoptotic BCL-2 proteins and suppression of BAX as mechanisms of AML resistance to individual BH3 mimetics. Cotargeting of MCL-1 and BCL-2 eliminates otherwise apoptosis-resistant cells.


Assuntos
Proteínas Reguladoras de Apoptose , Materiais Biomiméticos , Leucemia Mieloide Aguda , Animais , Apoptose , Materiais Biomiméticos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linhagem Celular Tumoral , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Camundongos , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteínas Proto-Oncogênicas c-bcl-2 , Células-Tronco/metabolismo , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/farmacologia
16.
Sci Rep ; 12(1): 3485, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241733

RESUMO

The threat of a nuclear attack has increased in recent years highlighting the benefit of developing additional therapies for the treatment of victims suffering from Acute Radiation Syndrome (ARS). In this work, we evaluated the impact of a PEGylated thrombopoietin mimetic peptide, JNJ-26366821, on the mortality and hematopoietic effects associated with ARS in mice exposed to lethal doses of total body irradiation (TBI). JNJ-26366821 was efficacious as a mitigator of mortality and thrombocytopenia associated with ARS in both CD2F1 and C57BL/6 mice exposed to TBI from a cobalt-60 gamma-ray source. Single administration of doses ranging from 0.3 to 1 mg/kg, given 4, 8, 12 or 24 h post-TBI (LD70 dose) increased survival by 30-90% as compared to saline control treatment. At the conclusion of the 30-day study, significant increases in bone marrow colony forming units and megakaryocytes were observed in animals administered JNJ-26366821 compared to those administered saline. In addition, enhanced recovery of FLT3-L levels was observed in JNJ-26366821-treated animals. Probit analysis of survival in the JNJ-26366821- and saline-treated cohorts revealed a dose reduction factor of 1.113 and significant increases in survival for up to 6 months following irradiation. These results support the potential use of JNJ-26366821 as a medical countermeasure for treatment of acute TBI exposure in case of a radiological/nuclear event when administered from 4 to 24 h post-TBI.


Assuntos
Síndrome Aguda da Radiação , Materiais Biomiméticos , Sistema Hematopoético , Trombopoetina , Síndrome Aguda da Radiação/tratamento farmacológico , Síndrome Aguda da Radiação/patologia , Animais , Materiais Biomiméticos/farmacologia , Sistema Hematopoético/patologia , Sistema Hematopoético/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Lesões Experimentais por Radiação/tratamento farmacológico , Lesões Experimentais por Radiação/patologia , Trombopoetina/farmacologia , Irradiação Corporal Total
17.
Carbohydr Polym ; 283: 119142, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35153015

RESUMO

Bone repair is a self-healing process. However, critical-sized bone defects need bone augmentation where bone tissue engineering plays vital role. Bone tissue Engineering (BTE) requires unique combinations of scaffolds, cells, and bio-signal molecules. Bone scaffold materials should be biocompatible, bioresorbable and exhibit biomimetic properties. Natural polymers, acquiring cell binding motives, producing nontoxic degradation products and tunable properties are ideal materials. Anionic polysaccharides of natural origin mimic mammalian ECM components and even the group called GAGs (Glycosaminoglycan) are actual components of ECM possessing various functions including cell adhesion, cell signaling, maintenance of homeostasis and inflammation control. Among them, anionic polysaccharides provide stabilization and sustained release of growth factors (GFs), porosity, calcium phosphate nucleation site, viscoelasticity, and water retention. Therefore, anionic polysaccharides are unique biomaterials for BTE. In this review, we have summarized the highlights of bone tissue engineering and recent applications of anionic polysaccharides in BTE.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/metabolismo , Polissacarídeos/farmacologia , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Ânions/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biomiméticos/farmacologia , Adesão Celular/efeitos dos fármacos , Glicosaminoglicanos/química , Humanos , Masculino , Osteogênese/efeitos dos fármacos , Polímeros/química , Polissacarídeos/química , Porosidade , Ratos
18.
J Mater Chem B ; 10(4): 637-645, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-34991154

RESUMO

Chemodynamic therapy (CDT) is an emerging approach to treat cancer based on the tumor microenvironment (TME), but its limited content of endogenous hydrogen peroxide (H2O2) weakens the anticancer effects. Herein, a multifunctional biomimetic nanozyme (Se@SiO2-Mn@Au/DOX, named as SSMA/DOX) is fabricated, which undergoes TME responsive self-cascade catalysis to facilitate MRI guided enhanced chemo/chemodynamic therapy. The SSMA/DOX nanocomposites (NCs) responsively degrade in acidic conditions of tumor to release Se, DOX, Au and Mn2+. Mn2+ not only enables MRI to guided therapy, but also catalyzes the endogenous H2O2 into hydroxyl radical (˙OH) for CDT. In addition, the Au NPs continuously catalyze glucose to generate H2O2, enhancing CDT by supplementing a sufficiently reactive material and cutting off the energy supply of the tumor by consuming glucose. Simultaneously, Se enhances the chemotherapy of doxorubicin hydrochloride (DOX) and CDT by upregulating ROS in the tumor cells, achieving remarkable inhibition effect towards tumor. Moreover, SSMA/DOX NCs have good biocompatibility and degradability, which avoid long-term toxicity and side effects. Overall, the degradable SSMA/DOX NCs provide an innovative strategy for tumor microenvironment responsive self-cascade catalysis to enhance tumor therapy.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Terapia Fototérmica , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Antineoplásicos/química , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Catálise , Linhagem Celular , Doxorrubicina/química , Feminino , Ouro/química , Ouro/farmacologia , Humanos , Manganês/química , Manganês/farmacologia , Teste de Materiais , Ratos , Ratos Sprague-Dawley , Selênio/química , Selênio/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Microambiente Tumoral/efeitos dos fármacos
19.
Chem Commun (Camb) ; 58(10): 1554-1557, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35014630

RESUMO

A homotypic cancer cell membrane camouflaged zeolitic imidazolate framework (ZIF)-based nanoagent with co-loading of two inhibitors was developed, which could suppress the efflux of protons to induce intracellular acidic stress and down-regulate glutamine metabolism to reduce the energy supply. As a compensation, glycometabolism would be upregulated with simultaneous production of large amounts of lactic acid, which could in turn aggravate the acidosis and further realize a synergetic cancer treatment.


Assuntos
Materiais Biomiméticos/química , Glutamina/metabolismo , Nanopartículas/química , Zeolitas/química , Animais , Materiais Biomiméticos/metabolismo , Materiais Biomiméticos/farmacologia , Materiais Biomiméticos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/química , Humanos , Imidazóis/química , Ácido Láctico/metabolismo , Células MCF-7 , Neoplasias/tratamento farmacológico , Sulfetos/química , Tiadiazóis/química
20.
J Biol Chem ; 298(3): 101612, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35065969

RESUMO

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease in which motor neurons progressively and rapidly degenerate, eventually leading to death. The first protein found to contain ALS-associated mutations was copper/zinc superoxide dismutase 1 (SOD1), which is conformationally stable when it contains its metal ligands and has formed its native intramolecular disulfide. Mutations in SOD1 reduce protein folding stability via disruption of metal binding and/or disulfide formation, resulting in misfolding, aggregation, and ultimately cellular toxicity. A great deal of effort has focused on preventing the misfolding and aggregation of SOD1 as a potential therapy for ALS; however, the results have been mixed. Here, we utilize a small-molecule polytherapy of diacetylbis(N(4)-methylthiosemicarbazonato)copper(II) (CuATSM) and ebselen to mimic the metal delivery and disulfide bond promoting activity of the cellular chaperone of SOD1, the "copper chaperone for SOD1." Using microscopy with automated image analysis, we find that polytherapy using CuATSM and ebselen is highly effective and acts in synergy to reduce inclusion formation in a cell model of SOD1 aggregation for multiple ALS-associated mutants. Polytherapy reduces mutant SOD1-associated cell death, as measured by live-cell microscopy. Measuring dismutase activity via zymography and immunoblotting for disulfide formation showed that polytherapy promoted more effective maturation of transfected SOD1 variants beyond either compound alone. Our data suggest that a polytherapy of CuATSM and ebselen may merit more study as an effective method of treating SOD1-associated ALS.


Assuntos
Esclerose Amiotrófica Lateral , Compostos de Cobre Orgânico , Superóxido Dismutase-1 , Esclerose Amiotrófica Lateral/tratamento farmacológico , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/metabolismo , Materiais Biomiméticos/farmacologia , Cobre/metabolismo , Dissulfetos/química , Humanos , Isoindóis/farmacologia , Chaperonas Moleculares/metabolismo , Mutação , Compostos de Cobre Orgânico/farmacologia , Compostos Organosselênicos/farmacologia , Dobramento de Proteína/efeitos dos fármacos , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
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