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2.
Adv Sci (Weinh) ; 11(2): e2302965, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37946710

RESUMO

Interactions between living cells and nanoparticles are extensively studied to enhance the delivery of therapeutics. Nanoparticles size, shape, stiffness, and surface charge are regarded as the main features able to control the fate of cell-nanoparticle interactions. However, the clinical translation of nanotherapies has so far been limited, and there is a need to better understand the biology of cell-nanoparticle interactions. This study investigates the role of cellular mechanosensitive components in cell-nanoparticle interactions. It is demonstrated that the genetic and pharmacologic inhibition of yes-associated protein (YAP), a key component of cancer cell mechanosensing apparatus and Hippo pathway effector, improves nanoparticle internalization in triple-negative breast cancer cells regardless of nanoparticle properties or substrate characteristics. This process occurs through YAP-dependent regulation of endocytic pathways, cell mechanics, and membrane organization. Hence, the study proposes targeting YAP may sensitize triple-negative breast cancer cells to chemotherapy and increase the selectivity of nanotherapy.


Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Transdução de Sinais/fisiologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Proteínas de Sinalização YAP
3.
Adv Sci (Weinh) ; 11(8): e2305769, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38054651

RESUMO

The application of lipid-based nanoparticles for COVID-19 vaccines and transthyretin-mediated amyloidosis treatment have highlighted their potential for translation to cancer therapy. However, their use in delivering drugs to solid tumors is limited by ineffective targeting, heterogeneous organ distribution, systemic inflammatory responses, and insufficient drug accumulation at the tumor. Instead, the use of lipid-based nanoparticles to remotely activate immune system responses is an emerging effective strategy. Despite this approach showing potential for treating hematological cancers, its application to treat solid tumors is hampered by the selection of eligible targets, tumor heterogeneity, and ineffective penetration of activated T cells within the tumor. Notwithstanding, the use of lipid-based nanoparticles for immunotherapy is projected to revolutionize cancer therapy, with the ultimate goal of rendering cancer a chronic disease. However, the translational success is likely to depend on the use of predictive tumor models in preclinical studies, simulating the complexity of the tumor microenvironment (e.g., the fibrotic extracellular matrix that impairs therapeutic outcomes) and stimulating tumor progression. This review compiles recent advances in the field of antitumor lipid-based nanoparticles and highlights emerging therapeutic approaches (e.g., mechanotherapy) to modulate tumor stiffness and improve T cell infiltration, and the use of organoids to better guide therapeutic outcomes.


Assuntos
Neuropatias Amiloides Familiares , Neoplasias , Humanos , Vacinas contra COVID-19 , Imunoterapia , Neoplasias/terapia , Lipídeos , Microambiente Tumoral
4.
Nanomaterials (Basel) ; 13(19)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37836350

RESUMO

The quest for biocompatible drug-delivery devices that could be able to open new administration routes is at the frontier of biomedical research. In this contribution, porous polysaccharide-based microsponges based on crosslinked alginate polymers were developed and characterized by optical spectroscopy and nanoscopic microscopy techniques. We show that macropores with a size distribution ranging from 50 to 120 nm enabled efficient loading and delivery of a therapeutic peptide (CIGB814), presently under a phase 3 clinical trial for the treatment of rheumatoid arthritis. Alginate microsponges showed 80% loading capacity and sustained peptide release over a few hours through a diffusional mechanism favored by partial erosion of the polymer scaffold. The edible and biocompatible nature of alginate polymers open promising perspectives for developing a new generation of polysaccharide-based carriers for the controlled delivery of peptide drugs, exploiting alternative routes with respect to intravenous administration.

5.
Molecules ; 28(13)2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37446588

RESUMO

Ultrasound-based engineering of carrier-free nanodrugs by supramolecular self-assembly has recently emerged as an innovative and environmentally friendly synthetic approach. By applying high-frequency sound waves (490 kHz) in aqueous solutions, the transformation of small chemotherapeutic and antibiotic drug molecules into carrier-free nanodrugs with anticancer and antimicrobial activities was recently achieved. The transformation of the antibiotic drug molecules, i.e., doxycycline, into stable nanodrugs (~130 nm) with selective anticancer activity was achieved without requiring organic solvents, chemical agents, or surfactants. The obtained nanodrug exhibited reactive oxygen species (ROS)-mediated cytotoxicity on human breast cancer (MDA-MB 231 cells) but a negligible antiproliferative effect on healthy fibroblast cells. Imaging by super-resolution microscopy (STORM) provided insights into the intracellular trafficking and endosomal escape of the nanodrugs. Overall, these findings suggest that small antibiotic drugs can be transformed into chemotherapeutic nanodrugs with high selectivity against cancer cells.


Assuntos
Antineoplásicos , Nanopartículas , Humanos , Antibacterianos/farmacologia , Ultrassom , Nanopartículas/uso terapêutico , Nanopartículas/química , Antineoplásicos/farmacologia , Antineoplásicos/química
6.
Adv Mater ; 35(21): e2210392, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36908046

RESUMO

Glucose-responsive insulin-delivery platforms that are sensitive to dynamic glucose concentration fluctuations and provide both rapid and prolonged insulin release have great potential to control hyperglycemia and avoid hypoglycemia diabetes. Here, biodegradable and charge-switchable phytoglycogen nanoparticles capable of glucose-stimulated insulin release are engineered. The nanoparticles are "nanosugars" bearing glucose-sensitive phenylboronic acid groups and amine moieties that allow effective complexation with insulin (≈95% loading capacity) to form nanocomplexes. A single subcutaneous injection of nanocomplexes shows a rapid and efficient response to a glucose challenge in two distinct diabetic mouse models, resulting in optimal blood glucose levels (below 200 mg dL-1 ) for up to 13 h. The morphology of the nanocomplexes is found to be key to controlling rapid and extended glucose-regulated insulin delivery in vivo. These studies reveal that the injected nanocomplexes enabled efficient insulin release in the mouse, with optimal bioavailability, pharmacokinetics, and safety profiles. These results highlight a promising strategy for the development of a glucose-responsive insulin delivery system based on a natural and biodegradable nanosugar.


Assuntos
Diabetes Mellitus Experimental , Camundongos , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Glucose , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/uso terapêutico , Insulina
7.
Angew Chem Int Ed Engl ; 62(12): e202214935, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36700351

RESUMO

DNA-based materials have attracted interest due to the tunable structure and encoded biological functionality of nucleic acids. A simple and general approach to synthesize DNA-based materials with fine control over morphology and bioactivity is important to expand their applications. Here, we report the synthesis of DNA-based particles via the supramolecular assembly of tannic acid (TA) and DNA. Uniform particles with different morphologies are obtained using a variety of DNA building blocks. The particles enable the co-delivery of cytosine-guanine adjuvant sequences and the antigen ovalbumin in model cells. Intramuscular injection of the particles in mice induces antigen-specific antibody production and T cell responses with no apparent toxicity. Protein expression in cells is shown using capsules assembled from TA and plasmid DNA. This work highlights the potential of TA as a universal material for directing the supramolecular assembly of DNA into gene and vaccine delivery platforms.


Assuntos
Adjuvantes Imunológicos , Polifenóis , Camundongos , Animais , Adjuvantes Imunológicos/química , Antígenos , Sistemas de Liberação de Medicamentos , DNA/química
8.
Sci Transl Med ; 14(672): eabo5715, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36417487

RESUMO

Cardiac pathologies are characterized by intense remodeling of the extracellular matrix (ECM) that eventually leads to heart failure. Cardiomyocytes respond to the ensuing biomechanical stress by reexpressing fetal contractile proteins via transcriptional and posttranscriptional processes, such as alternative splicing (AS). Here, we demonstrate that the heterogeneous nuclear ribonucleoprotein C (hnRNPC) is up-regulated and relocates to the sarcomeric Z-disc upon ECM pathological remodeling. We show that this is an active site of localized translation, where the ribonucleoprotein associates with the translation machinery. Alterations in hnRNPC expression, phosphorylation, and localization can be mechanically determined and affect the AS of mRNAs involved in mechanotransduction and cardiovascular diseases, including Hippo pathway effector Yes-associated protein 1. We propose that cardiac ECM remodeling serves as a switch in RNA metabolism by affecting an associated regulatory protein of the spliceosome apparatus. These findings offer new insights on the mechanism of mRNA homeostatic mechanoregulation in pathological conditions.


Assuntos
Insuficiência Cardíaca , Ribonucleoproteínas Nucleares Heterogêneas Grupo C , Humanos , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/metabolismo , Mecanotransdução Celular , Miócitos Cardíacos/metabolismo , Insuficiência Cardíaca/metabolismo , Matriz Extracelular/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Sci Rep ; 12(1): 17409, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36257968

RESUMO

Cardiovascular diseases remain the leading cause of death worldwide; hence there is an increasing focus on developing physiologically relevant in vitro cardiovascular tissue models suitable for studying personalized medicine and pre-clinical tests. Despite recent advances, models that reproduce both tissue complexity and maturation are still limited. We have established a scaffold-free protocol to generate multicellular, beating human cardiac microtissues in vitro from hiPSCs-namely human organotypic cardiac microtissues (hOCMTs)-that show some degree of self-organization and can be cultured for long term. This is achieved by the differentiation of hiPSC in 2D monolayer culture towards cardiovascular lineage, followed by further aggregation on low-attachment culture dishes in 3D. The generated hOCMTs contain multiple cell types that physiologically compose the heart and beat without external stimuli for more than 100 days. We have shown that 3D hOCMTs display improved cardiac specification, survival and metabolic maturation as compared to standard monolayer cardiac differentiation. We also confirmed the functionality of hOCMTs by their response to cardioactive drugs in long-term culture. Furthermore, we demonstrated that they could be used to study chemotherapy-induced cardiotoxicity. Due to showing a tendency for self-organization, cellular heterogeneity, and functionality in our 3D microtissues over extended culture time, we could also confirm these constructs as human cardiac organoids (hCOs). This study could help to develop more physiologically-relevant cardiac tissue models, and represent a powerful platform for future translational research in cardiovascular biology.


Assuntos
Antineoplásicos , Fármacos Cardiovasculares , Células-Tronco Pluripotentes Induzidas , Humanos , Engenharia Tecidual/métodos , Coração/fisiologia , Diferenciação Celular/fisiologia , Fármacos Cardiovasculares/metabolismo , Antineoplásicos/metabolismo , Miócitos Cardíacos/metabolismo
11.
Ultrason Sonochem ; 90: 106183, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36201933

RESUMO

Nisin, a peptide used as a natural food preservative, is employed in this work for the development of a novel nanocarrier system. Stable and uniform nisin-shelled nanoemulsions (NSNE) with a diameter of 100 ± 20 nm were successfully prepared using 20 kHz flow-through ultrasonication technique. The NSNE showed limited toxicity, high bactericidal activity and high drug loading capacity (EE 65 % w/w). In addition, the nisin shell was exploited for the site-specific attachment of a recombinantly produced cancer targeting ligand (αHER2LPETG IgG). Employing a unique two phases (bio-click) approach which involved both Sortase A mediated Azide Bioconjugation (SMAB) and Strain Promoted Azide Alkyne Cycloaddition (SPAAC) reactions, targeted NSNE (NSNEDOX-αHER2 IgG) were successfully assembled and loaded with the chemotherapeutic drug Doxorubicin (DOX). Finally, NSNEDOX-αHER2 IgG showed cancer-specific binding and augmented cytotoxicity to HER2 expressing tumour cells.


Assuntos
Neoplasias , Nisina , Humanos , Azidas , Nisina/farmacologia , Doxorrubicina/farmacologia , Imunoglobulina G
12.
Biomater Adv ; 140: 213083, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36027666

RESUMO

Glycogen-nucleic acid constructs i.e., glycoplexes are emerging promising platforms for the alteration of gene expression and transcription. Understanding the interaction of glycoplexes with human blood components, such as serum proteins and peripheral blood mononuclear cells (PBMCs), is important to overcome immune cell activation and control biodistribution upon administration of the glycoplexes in vivo. Herein, we investigated the interactions of polyethylene glycol (PEG)ylated and non-PEGylated glycoplexes carrying siRNA molecules with PBMCs isolated from the blood of healthy donors. We found that both types of glycoplexes were non-toxic and were primarily phagocytosed by monocytes without triggering a pro-inflammatory interleukin 6 cytokine production. Furthermore, we investigated the role of the protein corona on controlling the internalization efficiency in immune cells - we found that the adsorption of serum proteins, in particular haptoglobin, alpha-1-antitrypsin and apolipoprotein A-II, onto the non-PEGylated glycoplexes, significantly reduced the uptake of the glycoplexes by PBMCs. Moreover, the non-PEGylated glycoplexes were efficient in the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) knockdown in monocytic THP-1 cell line. This study provides an insight into the rational design of glycogen-based nanocarriers for the safe delivery of siRNA without eliciting unwanted immune cell activation and efficient siRNA activity upon its delivery.


Assuntos
Coroa de Proteína , Proteínas Sanguíneas/metabolismo , Glicogênio/metabolismo , Humanos , Leucócitos Mononucleares/metabolismo , Coroa de Proteína/metabolismo , RNA Interferente Pequeno/genética , Distribuição Tecidual
13.
Ultrason Sonochem ; 86: 106029, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35561593

RESUMO

Transforming small-molecule antibiotics into carrier-free nanoantibiotics represents an opportunity for developing new multifunctional therapeutic agents. In this study, we demonstrate that acoustic cavitation produced by high-frequency ultrasound transforms the antibiotic doxycycline into carrier-free nanobiotics. Upon sonication for 1 h at 10-15 W cm-3, doxycycline molecules underwent hydroxylation and dimerization processes to ultimately self-assemble into nanoparticles of ∼100-200 nm in size. Micrometer sized particles can be also obtained by increasing the acoustic power to 20 W cm-3. The nanodrugs exhibited antioxidant properties, along with antimicrobial activity against both Gram-positive (S. aureus) and Gram-negative (E. coli) bacterial strains. Our results highlight the feasibility of the ultrasound-based approach for engineering drug molecules into a nanosized formulation with controlled and multiple bio-functionalities.


Assuntos
Anti-Infecciosos , Antioxidantes , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Doxiciclina , Escherichia coli , Staphylococcus aureus
14.
Ultrason Sonochem ; 86: 106016, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35525092

RESUMO

We report on the fabrication of lysozyme microspheres (LyMs) incorporated with gold nanorods (NRs) as a distinctive approach for the encapsulation and release of an anticancer drug, 5-Fluorouracil (5-FU). LyMs with an average size of 4.0 ± 1.0 µm were prepared by a sonochemical method and characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR). The LyMs were examined using hydrophobic (nile red) as well as hydrophilic (trypan blue) dyes under confocal laser scanning microscopy (CLSM) to obtain information about the preferential distribution of fluorescent molecules. Notably, the fluorescent molecules were accumulated in the inner lining of LyMs as the core was occupied with air. The encapsulation efficiency of 5-FU for LyMs-NR was found to be ∼64%. The drug release from control LyMs as well as LyMs incorporated with NRs was investigated under the influence of ultrasound (US) at 200 kHz. The total release for control LyMs and LyMs incorporated with gold NRs was found to be ∼70 and 95% after 1 h, respectively. The density difference caused by NR incorporation on the shell played a key role in rupturing the LyMs-NR under US irradiation. Furthermore, 5-FU loaded LyMs-NR exhibited excellent anti-cancer activity against the THP-1 cell line (∼90% cell death) when irradiated with US of 200 kHz. The enhanced anti-cancer activity of LyMs-NR was caused by the transfer of released 5-FU molecules from bulk to the interior of the cell via temporary pores formed on the surface of cancer cells, i.e., sonoporation. Thus, LyMs-NR demonstrated here has a high potential for use as carriers in the field of drug delivery, bio-imaging and therapy.


Assuntos
Muramidase , Nanotubos , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Fluoruracila/química , Fluoruracila/farmacologia , Ouro , Microesferas , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Pharmaceutics ; 14(2)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35214170

RESUMO

Recently, several studies have indicated an increased interest in the scientific community regarding the application of Cannabis sativa plants, and their extracts, for medicinal purposes. This plant of enormous medicinal potential has been legalised in an increasing number of countries globally. Due to the recent changes in therapeutic and recreational legislation, cannabis and cannabinoids are now frequently permitted for use in clinical settings. However, with their highly lipophilic features and very low aqueous solubility, cannabinoids are prone to degradation, specifically in solution, as they are light-, temperature-, and auto-oxidation-sensitive. Thus, plant-derived cannabinoids have been developed for oral, nasal-inhalation, intranasal, mucosal (sublingual and buccal), transcutaneous (transdermal), local (topical), and parenteral deliveries. Among these administrations routes, topical and transdermal products usually have a higher bioavailability rate with a prolonged steady-state plasma concentration. Additionally, these administrations have the potential to eliminate the psychotropic impacts of the drug by its diffusion into a nonreactive, dead stratum corneum. This modality avoids oral administration and, thus, the first-pass metabolism, leading to constant cannabinoid plasma levels. This review article investigates the practicality of delivering therapeutic cannabinoids via skin in accordance with existing literature.

16.
Nanoscale ; 14(8): 3049-3061, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35142755

RESUMO

Real-time detection and nanoscale imaging of human immunodeficiency virus type 1 ribonucleic acid (HIV-1 RNA) in latently infected cells that persist in people living with HIV-1 on antiretroviral therapy in blood and tissue may reveal new insights needed to cure HIV-1 infection. Herein, we develop a strategy combining DNA nanotechnology and super-resolution expansion microscopy (ExM) to detect and image a 22 base sequence transcribed from the HIV-1 promoter in model live and fixed cells. We engineer a chimeric locked nucleic acid (LNA)-DNA sensor via hybridization chain reaction to probe HIV-1 RNA in the U3 region of the HIV-1 long terminal repeat (LTR) by signal amplification in live cells. We find that the viral RNA transcript of the U3 region of the HIV-1 LTR, namely PromA, is a valid and specific biomarker to detect infected live cells. The efficiency and selectivity of the LNA-DNA sensor are evaluated in combination with ExM. Unlike standard ExM methods, which rely on additional custom linkers to anchor and immobilize RNA molecules in the intracellular polymeric network, in the current strategy, we probe and image the HIV-1 RNA target at nanoscale resolution, without resorting to chemical linkers or additional preparation steps. This is achieved by physical entrapment of the HIV-1 viral transcripts in the cells post-expansion by finely tuning the mesh size of the intracellular polymeric network.


Assuntos
HIV-1 , DNA , HIV-1/genética , Humanos , Oligonucleotídeos , RNA Viral/genética
17.
Nanoscale ; 14(9): 3452-3466, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35179174

RESUMO

Engineered nanoparticles for the encapsulation of bioactive agents hold promise to improve disease diagnosis, prevention and therapy. To advance this field and enable clinical translation, the rational design of nanoparticles with controlled functionalities and a robust understanding of nanoparticle-cell interactions in the complex biological milieu are of paramount importance. Herein, a simple platform obtained through the nanocomplexation of glycogen nanoparticles and albumin is introduced for the delivery of chemotherapeutics in complex multicellular 2D and 3D systems. We found that the dendrimer-like structure of aminated glycogen nanoparticles is key to controlling the multivalent coordination and phase separation of albumin molecules to form stable glycogen-albumin nanocomplexes. The pH-responsive glycogen scaffold conferred the nanocomplexes the ability to undergo partial endosomal escape in tumour, stromal and immune cells while albumin enabled nanocomplexes to cross endothelial cells and carry therapeutic agents. Limited interactions of nanocomplexes with T cells, B cells and natural killer cells derived from human blood were observed. The nanocomplexes can accommodate chemotherapeutic drugs and release them in multicellular 2D and 3D constructs. The drugs loaded on the nanocomplexes retained their cytotoxic activity, which is comparable with the activity of the free drugs. Cancer cells were found to be more sensitive to the drugs in the presence of stromal and immune cells. Penetration and cytotoxicity of the drug-loaded nanocomplexes in tumour mimicking tissues were validated using a 3D multicellular-collagen construct in a perfusion bioreactor. The results highlight a simple and potentially scalable strategy for engineering nanocomplexes made entirely of biological macromolecules with potential use for drug delivery.


Assuntos
Albuminas , Antineoplásicos , Glicogênio , Nanopartículas , Albuminas/química , Antineoplásicos/administração & dosagem , Células Endoteliais , Glicogênio/química , Humanos , Nanopartículas/química
18.
Adv Mater ; 34(13): e2107964, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35100658

RESUMO

Reconfiguring the structure and selectivity of existing chemotherapeutics represents an opportunity for developing novel tumor-selective drugs. Here, as a proof-of-concept, the use of high-frequency sound waves is demonstrated to transform the nonselective anthracycline doxorubicin into a tumor selective drug molecule. The transformed drug self-aggregates in water to form ≈200 nm nanodrugs without requiring organic solvents, chemical agents, or surfactants. The nanodrugs preferentially interact with lipid rafts in the mitochondria of cancer cells. The mitochondrial localization of the nanodrugs plays a key role in inducing reactive oxygen species mediated selective death of breast cancer, colorectal carcinoma, ovarian carcinoma, and drug-resistant cell lines. Only marginal cytotoxicity (80-100% cell viability) toward fibroblasts and cardiomyocytes is observed, even after administration of high doses of the nanodrug (25-40 µg mL-1 ). Penetration, cytotoxicity, and selectivity of the nanodrugs in tumor-mimicking tissues are validated by using a 3D coculture of cancer and healthy cells and 3D cell-collagen constructs in a perfusion bioreactor. The nanodrugs exhibit tropism for lung and limited accumulation in the liver and spleen, as suggested by in vivo biodistribution studies. The results highlight the potential of this approach to transform the structure and bioactivity of anticancer drugs and antibiotics bearing sono-active moieties.


Assuntos
Nanopartículas , Neoplasias Ovarianas , Antibióticos Antineoplásicos/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Humanos , Nanopartículas/química , Distribuição Tecidual
19.
ACS Nano ; 16(1): 98-110, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34843208

RESUMO

Metal-phenolic networks (MPNs) are amorphous materials that can be used to engineer functional films and particles. A fundamental understanding of the heat-driven structural reorganization of MPNs can offer opportunities to rationally tune their properties (e.g., size, permeability, wettability, hydrophobicity) for applications such as drug delivery, sensing, and tissue engineering. Herein, we use a combination of single-molecule localization microscopy, theoretical electronic structure calculations, and all-atom molecular dynamics simulations to demonstrate that MPN plasticity is governed by both the inherent flexibility of the metal (FeIII)-phenolic coordination center and the conformational elasticity of the phenolic building blocks (tannic acid, TA) that make up the metal-organic coordination complex. Thermal treatment (heating to 150 °C) of the flexible TA/FeIII networks induces a considerable increase in the number of aromatic π-π interactions formed among TA moieties and leads to the formation of hydrophobic domains. In the case of MPN capsules, 15 min of heating induces structural rearrangements that cause the capsules to shrink (from ∼4 to ∼3 µm), resulting in a thicker (3-fold), less porous, and higher protein (e.g., bovine serum albumin) affinity MPN shell. In contrast, when a simple polyphenol such as gallic acid is complexed with FeIII to form MPNs, rigid materials that are insensitive to temperature changes are obtained, and negligible structural rearrangement is observed upon heating. These findings are expected to facilitate the rational engineering of versatile TA-based MPN materials with tunable physiochemical properties for diverse applications.


Assuntos
Complexos de Coordenação , Compostos Férricos , Cápsulas/química , Compostos Férricos/química , Microscopia , Fenóis , Metais/química , Complexos de Coordenação/química , Elasticidade
20.
J Pept Sci ; 28(1): e3356, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34114297

RESUMO

Synthetic therapeutic peptides (STP) are intensively studied as new-generation drugs, characterized by high purity, biocompatibility, selectivity and stereochemical control. However, most of the studies are focussed on the bioactivity of STP without considering how the formulation actually used for therapy administration could alter the physico-chemical properties of the active principle. The aggregation properties of a 20-mer STP (Ac-His-Ala-Arg-Ile-Lys-D-Pro-Thr-Phe-Arg-Arg-D-Leu-Lys-Trp-Lys-Tyr-Lys-Gly-Lys-Phe-Trp-NH2 ), showing antitumor activity, were investigated by optical spectroscopy and atomic force microscopy imaging, as itself (CIGB552) and in its therapeutic formulation (CIGB552TF). It has found that the therapeutic formulation deeply affects the aggregation properties of the investigated peptide and the morphology of the aggregates formed on mica by deposition of CIGB552 and CIGB552TF millimolar solutions. Molecular dynamics simulations studied the first steps of CIGB552 aggregation under physiological ionic strength conditions (NaCl 150 mM), showing that peptide oligomers, from dimers to tetramers, are preferentially formed in this environment. Interestingly, cell viability assays performed on H-460 cell lines indicate a major antiproliferative activity of the peptide in its therapeutic formulation with respect to the peptide aqueous solution.


Assuntos
Simulação de Dinâmica Molecular , Fragmentos de Peptídeos , Sequência de Aminoácidos , Peptídeos , Análise Espectral
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