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1.
Molecules ; 29(10)2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38792228

RESUMEN

Vitamin D, an essential micronutrient crucial for skeletal integrity and various non-skeletal physiological functions, exhibits limited bioavailability and stability in vivo. This study is focused on the development of polyethylene glycol (PEG)-grafted phospholipid micellar nanostructures co-encapsulating vitamin D3 and conjugated with alendronic acid, aimed at active bone targeting. Furthermore, these nanostructures are rendered optically traceable in the UV-visible region of the electromagnetic spectrum via the simultaneous encapsulation of vitamin D3 with carbon dots, a newly emerging class of fluorescents, biocompatible nanoparticles characterized by their resistance to photobleaching and environmental friendliness, which hold promise for future in vitro bioimaging studies. A systematic investigation is conducted to optimize experimental parameters for the preparation of micellar nanostructures with an average hydrodynamic diameter below 200 nm, ensuring colloidal stability in physiological media while preserving the optical luminescent properties of the encapsulated carbon dots. Comprehensive chemical-physical characterization of these micellar nanostructures is performed employing optical and morphological techniques. Furthermore, their binding affinity for the principal inorganic constituent of bone tissue is assessed through a binding assay with hydroxyapatite nanoparticles, indicating significant potential for active bone-targeting. These formulated nanostructures hold promise for novel therapeutic interventions to address skeletal-related complications in cancer affected patients in the future.


Asunto(s)
Alendronato , Huesos , Colecalciferol , Micelas , Nanoestructuras , Colecalciferol/química , Nanoestructuras/química , Huesos/efectos de los fármacos , Huesos/metabolismo , Alendronato/química , Polietilenglicoles/química , Humanos , Sistemas de Liberación de Medicamentos , Luminiscencia , Nanopartículas/química , Portadores de Fármacos/química , Puntos Cuánticos/química
2.
Pharmaceutics ; 16(4)2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38675228

RESUMEN

Extracellular vesicles (EVs), acting as inherent nanocarriers adept at transporting a range of different biological molecules such as proteins, lipids, and genetic material, exhibit diverse functions within the gastroenteric tract. In states of normal health, they participate in the upkeep of systemic and organ homeostasis. Conversely, in pathological conditions, they significantly contribute to the pathogenesis of gastrointestinal diseases (GIDs). Isolating EVs from patients' biofluids facilitates the discovery of new biomarkers that have the potential to offer a rapid, cost-effective, and non-invasive method for diagnosing and prognosing specific GIDs. Furthermore, EVs demonstrate considerable therapeutic potential as naturally targeted physiological carriers for the intercellular delivery of therapeutic cargo molecules or as nanoscale tools engineered specifically to regulate physio-pathological conditions or disease progression. Their attributes including safety, high permeability, stability, biocompatibility, low immunogenicity, and homing/tropism capabilities contribute to their promising clinical therapeutic applications. This review will delve into various examples of EVs serving as biomarkers or nanocarriers for therapeutic cargo in the context of GIDs, highlighting their clinical potential for both functional and structural gastrointestinal conditions. The versatile and advantageous properties of EVs position them as promising candidates for innovative therapeutic strategies in advancing personalized medicine approaches tailored to the gastroenteric tract, addressing both functional and structural GIDs.

3.
JMIR Form Res ; 8: e51021, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38306176

RESUMEN

BACKGROUND: Chronic pain is one of the most common and critical long-term effects of breast cancer. Digital health technologies enhance the management of chronic pain by monitoring physical and psychological health status and supporting pain self-management and patient treatment decisions throughout the clinical pathway. OBJECTIVE: This pilot study aims to evaluate patients' experiences, including usability, with a novel digital integrated health ecosystem for chronic pain named PainRELife. The sample included patients with breast cancer during survivorship. The PainRELife ecosystem comprises a cloud technology platform interconnected with electronic health records and patients' devices to gather integrated health care data. METHODS: We enrolled 25 patients with breast cancer (mean age 47.12 years) experiencing pain. They were instructed to use the PainRELife mobile app for 3 months consecutively. The Mobile Application Rating Scale (MARS) was used to evaluate usability. Furthermore, pain self-efficacy and participation in treatment decisions were evaluated. The study received ethical approval (R1597/21-IEO 1701) from the Ethical Committee of the European Institute of Oncology. RESULTS: The MARS subscale scores were medium to high (range: 3.31-4.18), and the total app quality score was 3.90. Patients with breast cancer reported reduced pain intensity at 3 months, from a mean of 5 at T0 to a mean of 3.72 at T2 (P=.04). The total number of times the app was accessed was positively correlated with pain intensity at 3 months (P=.03). The engagement (P=.03), information (P=.04), and subjective quality (P=.007) subscales were positively correlated with shared decision-making. Furthermore, participants with a lower pain self-efficacy at T2 (mean 40.83) used the mobile app more than participants with a higher pain self-efficacy (mean 48.46; P=.057). CONCLUSIONS: The data collected in this study highlight that digital health technologies, when developed using a patient-driven approach, might be valuable tools for increasing participation in clinical care by patients with breast cancer, permitting them to achieve a series of key clinical outcomes and improving quality of life. Digital integrated health ecosystems might be important tools for improving ongoing monitoring of physical status, psychological burden, and socioeconomic issues during the cancer survivorship trajectory. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/41216.

4.
Int J Mol Sci ; 25(3)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38338770

RESUMEN

Metabolic dysfunction-associated steatotic liver disease (MASLD) is closely related to some metabolic disorders, such as central obesity and type 2 diabetes (T2D). Glucagon-like peptide 1 receptor agonists (GLP-1RAs), such as semaglutide, may have therapeutic roles in MASLD associated with T2D. This study aims to investigate the molecular mechanisms underlying the effectiveness of semaglutide on MASLD in terms of progression from liver steatosis to fibrosis. We characterized exosomes from ten patients with type 2 diabetes (T2D) before (T0) and after 12 months (T12) of treatment with once-weekly subcutaneous semaglutide. Six of ten patients were considered responders to therapy (R) based on MASLD severity downgrading by at least one class according to a validated ultrasonographic (US) score. Normal hepatocytes (HEPA-RG) and stellate (LX-2) cells were challenged with exosomes from R and NR patients, isolated before and after 12 months of therapy. Exosomes from both R and NR patients isolated at T0 significantly affected LX-2 viability. After 12 months of treatment, only those isolated from R patients restored cell viability, whereas those from NR patients did not. No effects were observed on HEPA-RG cells. Exosomes at T12 from R but not from NR patients significantly decreased the production of α-SMA, a marker of LX-2 activation, a liver stellate cell model, and ph-SMAD2 and CTGF, involved in fibrosis processes. TGF-ß1 was not modulated by the exosomes of R and NR patients. As a downstream effect, Vimentin, Collagen 1A1, and Fibronectin extracellular matrix components were also downregulated, as measured by droplets digital PCR. In conclusion, these results shed light on the potential effectiveness of semaglutide in improving liver fibrosis in MASLD.


Asunto(s)
Diabetes Mellitus Tipo 2 , Exosomas , Hígado Graso , Péptidos Similares al Glucagón , Enfermedades Metabólicas , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Matriz Extracelular , Hígado Graso/tratamiento farmacológico , Fibrosis
5.
Cell Death Dis ; 14(9): 635, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37752143

RESUMEN

Excessive toxic lipid accumulation in hepatocytes underlies the development of non-alcoholic fatty liver disease (NAFLD), phenotypically characterized by necrosis and steato-fibrosis, whose molecular mechanism is not yet fully understood. Patients with NAFLD display an imbalanced palmitic (PA) to oleic acid (OA) ratio. Moreover, increasing experimental evidence points out a relevant involvement of the exosomal content in disease progression. Aim of the study was to highlight the PA/OA imbalance within circulating exosomes, the subsequent intracellular alterations, and the impact on NALFD. Liver cells were challenged with exosomes isolated from both healthy subjects and NAFLD patients. The exosomal PA/OA ratio was artificially modified, and biological effects were evaluated. A NAFLD-derived exosomal PA/OA imbalance impacts liver cell cycle and cell viability. OA-modified NAFLD-derived exosomes restored cellular viability and proliferation, whereas the inclusion of PA into healthy subjects-derived exosomes negatively affected cell viability. Moreover, while OA reduced the phosphorylation and activation of the necroptosis marker, Receptor-interacting protein 1 (phospho-RIP-1), PA induced the opposite outcome, alongside increased levels of stress fibers, such as vimentin and fibronectin. Administration of NAFLD-derived exosomes led to increased expression of Elongase 6 (ELOVL6), Stearoyl-CoA desaturase 1 (SCD1), Tumor necrosis factor α (TNF-α), Mixed-lineage-kinase-domain-like-protein (MLKL) and RIP-1 in the hepatocytes, comparable to mRNA levels in the hepatocytes of NAFLD patients reported in the Gene Expression Omnibus (GEO) database. Genetic and pharmacological abrogation of ELOVL6 elicited a reduced expression of downstream molecules TNF-α, phospho-RIP-1, and phospho-MLKL upon administration of NAFLD-derived exosomes. Lastly, mice fed with high-fat diet exhibited higher phospho-RIP-1 than mice fed with control diet. Targeting the Elongase 6-RIP-1 signaling pathway offers a novel therapeutic approach for the treatment of the NALFD-induced exosomal PA/OA imbalance.

6.
Nat Commun ; 14(1): 4646, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-37532724

RESUMEN

Resting heart rate is associated with cardiovascular diseases and mortality in observational and Mendelian randomization studies. The aims of this study are to extend the number of resting heart rate associated genetic variants and to obtain further insights in resting heart rate biology and its clinical consequences. A genome-wide meta-analysis of 100 studies in up to 835,465 individuals reveals 493 independent genetic variants in 352 loci, including 68 genetic variants outside previously identified resting heart rate associated loci. We prioritize 670 genes and in silico annotations point to their enrichment in cardiomyocytes and provide insights in their ECG signature. Two-sample Mendelian randomization analyses indicate that higher genetically predicted resting heart rate increases risk of dilated cardiomyopathy, but decreases risk of developing atrial fibrillation, ischemic stroke, and cardio-embolic stroke. We do not find evidence for a linear or non-linear genetic association between resting heart rate and all-cause mortality in contrast to our previous Mendelian randomization study. Systematic alteration of key differences between the current and previous Mendelian randomization study indicates that the most likely cause of the discrepancy between these studies arises from false positive findings in previous one-sample MR analyses caused by weak-instrument bias at lower P-value thresholds. The results extend our understanding of resting heart rate biology and give additional insights in its role in cardiovascular disease development.


Asunto(s)
Fibrilación Atrial , Enfermedades Cardiovasculares , Humanos , Enfermedades Cardiovasculares/genética , Factores de Riesgo , Frecuencia Cardíaca/genética , Predisposición Genética a la Enfermedad , Análisis de la Aleatorización Mendeliana/métodos , Estudio de Asociación del Genoma Completo/métodos , Polimorfismo de Nucleótido Simple
7.
ACS Appl Mater Interfaces ; 15(28): 33322-33334, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37417887

RESUMEN

Inflammasome activation plays a crucial role in the progression to more severe stages of non-alcoholic fatty liver disease (NAFLD), representing a promising therapeutic target. MCC950 is a small molecule acting as a potent and specific inhibitor of the canonical and non-canonical activation of the NLRP3 inflammasome, but its short plasmatic half-life limits its use. Herein, we report, for the first time, the encapsulation of MCC950 in poly(ethylene glycol) (PEG) liposomes (LPs) that are specifically functionalized with an antibody against Frizzled 1 (FZD1), a g-coupled protein involved in the WNT pathway and overexpressed on inflammasome-activated macrophages. MCC950, encapsulated into PEG-LP formulations conjugated with an anti-FZD1 antibody, inhibits the NLRP3 inflammasome activation at concentrations 10 times lower than that of the free drug in THP-1 cells. Luminescent carbon dots (CDs) were also co-encapsulated with MCC950 in LPs to obtain optically traceable nanoformulations that have proved the enhanced ability of the targeted LPs to be internalized into THP-1 cells with respect to their nontargeted counterparts. Our results suggest that MCC950 encapsulation into targeted LPs represents a valuable strategy to achieve reformulation of the NLRP3 inhibitor, able to significantly curtail the threshold of MCC950 doses for inhibiting inflammasome activation, thus offering a new therapeutic approach.


Asunto(s)
Indenos , Enfermedad del Hígado Graso no Alcohólico , Animales , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Liposomas , Sulfonas/farmacología , Disponibilidad Biológica , Lipopolisacáridos/farmacología , Sulfonamidas/farmacología , Furanos , Modelos Animales de Enfermedad
8.
Nat Chem ; 15(6): 781-786, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37169983

RESUMEN

Catenanes-molecules comprising two interlocking rings held together like links in a chain-are topologically non-trivial: a catenane is a topological isomer of its separated rings, but the rings cannot be disconnected without bond scission. Catenanes can exist as topological enantiomers if both rings have directionality conferred by a defined atom sequence, but this has led to the assumption that the stereochemistry of chiral catenanes composed of oriented rings is inherently topological in nature. Here we show that this assumption is incorrect by synthesizing an example that contains the same fundamental stereogenic unit but whose stereochemistry is Euclidean. One ring in this chiral catenane is oriented by the geometry of an exocyclic double rather than determined by atom sequence within the ring. Isomerization of the exocyclic double bond results in racemization of the catenane, confirming that the stereochemistry is not topological in nature. Thus, we can unite the stereochemistry of catenanes with that of their topologically trivial cousins, the rotaxanes, enabling a more unified approach to their discussion.

9.
JMIR Res Protoc ; 12: e41216, 2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37171843

RESUMEN

BACKGROUND: Chronic pain (CP) and its management are critical issues in the care pathway of patients with breast cancer. Considering the complexity of CP experience in cancer, the international scientific community has advocated identifying cutting-edge approaches for CP management. Recent advances in the field of health technology enable the adoption of a novel approach to care management by developing integrated ecosystems and mobile health apps. OBJECTIVE: The primary end point of this pilot study is to evaluate patients' usability experience at 3 months of a new digital and integrated technological ecosystem, PainRELife, for CP in a sample of patients with breast cancer. The PainRELife ecosystem is composed of 3 main technological assets integrated into a single digital ecosystem: Fast Healthcare Interoperability Resources-based cloud platform (Nu platform) that enables care pathway definition and data collection; a big data infrastructure connected to the Fast Healthcare Interoperability Resources server that analyzes data and implements dynamic dashboards for aggregate data visualization; and an ecosystem of personalized applications for patient-reported outcomes collection, digital delivery of interventions and tailored information, and decision support of patients and caregivers (PainRELife app). METHODS: This is an observational, prospective pilot study. Twenty patients with early breast cancer and chronic pain will be enrolled at the European Institute of Oncology at the Division of Medical Senology and the Division of Pain Therapy and Palliative Care. Each patient will use the PainRELife mobile app for 3 months, during which data extracted from the questionnaires will be sent to the Nu Platform that health care professionals will manage. This pilot study is nested in a large-scale project named "PainRELife," which aims to develop a cloud technology platform to interoperate with institutional systems and patients' devices to collect integrated health care data. The study received approval from the Ethical Committee of the European Cancer Institute in December 2021 (number R1597/21-IEO 1701). RESULTS: The recruitment process started in May 2022 and ended in October 2022. CONCLUSIONS: The new integrated technological ecosystems might be considered an encouraging affordance to enhance a patient-centered approach to managing patients with cancer. This pilot study will inform about which features the health technological ecosystems should have to be used by cancer patients to manage CP. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/41216.

10.
Front Oncol ; 13: 1129832, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36874116

RESUMEN

Introduction: Paclitaxel (PTX) interferes with microtubule architecture by binding to ß-tubulin, thereby blocking progression at the G2/M phase and inducing apoptosis. This study aimed to investigate molecular processes underlying PTX-mediated resistance in gastric cancer (GC) cells. Methods: PTX-mediated resistance involves many processes, and in this work some of the factors involved in the resistance mechanism were identified by comparing two GC lines with PTX induced resistance to their sensitive counterparts. Results: Thus, the key feature of PTX-resistant cells was the overexpression of pro-angiogenic factors such as VEGFA, VEGFC, and Ang2, known to support tumor cell growth. A second relevant change detected in PTX-resistant lines was the elevated level of TUBßIII, a tubulin isoform that opposes microtubule stabilization. A third identified factor contributing to PTX-resistance was P-glycoprotein (P-gp), a transporter responsible for chemotherapy efflux from the cells, highly expressed in PTX-resistant lines. Discussion: These findings were in line with a greater sensitivity of resistant cells to treatment with both Ramucirumab and Elacridar. Ramucirumab significantly reduced the expression of angiogenic molecules and TUBßIII, while Elacridar restored the access of chemotherapy, recovering its anti-mitotic and pro-apoptotic effects. Finally, this study highlighted the role played by exosomes in spreading factors responsible for resistance in the tumor microenvironment.

11.
Biomedicines ; 11(3)2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36979634

RESUMEN

It's known that a magnesium (Mg)-deficient diet is associated with an increased risk of osteoporosis. The aim of this work is to investigate, by a histological approach, the effects of a Mg-deprived diet on the bone of 8-weeks-old C57BL/6J male mice. Treated and control mice were supplied with a Mg-deprived or normal diet for 8 weeks, respectively. Body weight, serum Mg concentration, expression of kidney magnesiotropic genes, and histomorphometry on L5 vertebrae, femurs, and tibiae were evaluated. Body weight gain and serum Mg concentration were significantly reduced, while a trend toward increase was found in gene expression in mice receiving the Mg-deficient diet, suggesting the onset of an adaptive response to Mg depletion. Histomorphometric parameters on the amount of trabecular and cortical bone, number of osteoclasts, and thickness of the growth plate in femoral distal and tibial proximal metaphyses did not differ between groups; these findings partially differ from most data present in the literature showing that animals fed a Mg-deprived diet develop bone loss and may be only in part explained by differences among the experimental protocols. However, the unexpected findings we recorded on bones could be attributed to genetic differences that may have developed after multiple generations of inbreeding.

12.
Nanomaterials (Basel) ; 13(3)2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36770471

RESUMEN

Functionalization of colloidal nanoparticles with organic dyes, which absorb photons in complementary spectral ranges, brings a synergistic effect for harvesting additional light energy. Here, we show functionalization of near-infrared (NIR) plasmonic nanoparticles (NPs) of bare and amino-group functionalized mesoporous silica-coated copper sulphide (Cu2-xS@MSS and Cu2-xS@MSS-NH2) with specific tricarbocyanine NIR dye possessing sulfonate end groups. The role of specific surface chemistry in dye assembling on the surface of NPs is demonstrated, depending on the organic polar liquids or water used as a dispersant solvent. It is shown that dye binding to the NP surfaces occurs with different efficiency, but mostly in the monomer form in polar organic solvents. Conversely, the aqueous medium leads to different scenarios according to the NP surface chemistry. Predominant formation of the disordered dye monomers occurs on the bare surface of mesoporous silica shell (MSS), whereas the amino-group functionalized MSS accepts dye predominantly in the form of dimers. It is found that the dye-NP interaction overcomes the dye-dye interaction, leading to disruption of dye J-aggregates in the presence of the NPs. The different organization of the dye molecules on the surface of silica-coated copper sulphide NPs provides tuning of their specific functional properties, such as hot-band absorption and photoluminescence.

13.
J Enzyme Inhib Med Chem ; 38(1): 2163242, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36629431

RESUMEN

Androgen deprivation therapy (ADT) is a common treatment for recurrent prostate cancer (PC). However, after a certain period of responsiveness, ADT resistance occurs virtually in all patients and the disease progresses to lethal metastatic castration-resistant prostate cancer (mCRPC). Aberrant expression and function of the epigenetic modifiers EZH2 and BET over activates c-myc, an oncogenic transcription factor critically contributing to mCRPC. In the present work, we tested, for the first time, the combination of an EZH2 inhibitor with a BET inhibitor in metastatic PC cells. The combination outperformed single drugs in inhibiting cell viability, cell proliferation and clonogenic ability, and concomitantly reduced both c-myc and NF-kB expression. Although these promising results will warrant further in vivo validation, they represent the first step to establishing the rationale that the proposed combination might be suitable for mCRPC treatment, by exploiting molecular targets different from androgen receptor.


Asunto(s)
Antineoplásicos , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Antagonistas de Andrógenos/farmacología , Antagonistas de Andrógenos/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Proliferación Celular , Proteína Potenciadora del Homólogo Zeste 2/antagonistas & inhibidores , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología , Factores de Transcripción , Betaína-Homocisteína S-Metiltransferasa/antagonistas & inhibidores , Betaína-Homocisteína S-Metiltransferasa/metabolismo
14.
Int J Mol Sci ; 24(2)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36675254

RESUMEN

Exosomes produced by hepatocytes upon lipotoxic insult play a relevant role in pathogenesis of nonalcoholic fatty liver disease (NAFLD), suggesting an inflammatory response by the activation of monocytes and macrophages and accelerating the disease progression. In the pathogenesis of NAFLD and liver fibrosis, the endogenous cannabinoids and their major receptors CB1 and CB2 appear to be highly involved. This study aimed at evaluating the expression of cannabinoids receptors (CB1R and CB2R) in plasma-derived exosomes extracted from patients with NAFLD, as well as investigating the in vitro effects of the circulating exosomes in cultured human HepaRG cells following their introduction into the culture medium. The results demonstrated that plasma-derived exosomes from NAFLD patients are vehicles for the transport of CB1R and are able to modulate CB receptors' expression in HepaRG cells. In particular, circulating exosomes from NAFLD patients are inflammatory drivers for HepaRG cells, acting through CB1R activation and the downregulation of CB2R. Moreover, CB1R upregulation was associated with increased expression levels of PPAR-γ, a well-known mediator of liver tissue injury. In conclusion, this study provides evidence for CB1R transport by exosomes and suggests that the in vitro effects of circulating exosomes from NAFLD patients are mediated by the expression of cannabinoid receptors.


Asunto(s)
Cannabinoides , Exosomas , Enfermedad del Hígado Graso no Alcohólico , Humanos , Receptores de Cannabinoides , Receptor Cannabinoide CB1/genética
15.
J Am Chem Soc ; 144(50): 23127-23133, 2022 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-36508201

RESUMEN

Hydrogen-bonded supramolecular systems are usually characterized in solution through analysis of NMR data such as complexation-induced shifts and nuclear Overhauser effects (nOe). Routine direct detection of hydrogen bonding particularly in multicomponent mixtures, even with the aid of 2D NMR experiments for full assignment, is more challenging. We describe an elementary rapid 1H-15N HMQC NMR experiment which addresses these challenges without the need for complex pulse sequences. Under readily accessible conditions (243/263 K, 50 mM solutions) and natural 15N abundance, unambiguous assignment of 15N resonances facilitates direct detection of intra- and intermolecular hydrogen bonds in mechanically interlocked structures and quadruply hydrogen-bonded dimers─of dialkylaminoureidopyrimidinones, ureidopyrimidinones, and diamidonaphthyridines─in single or multicomponent mixtures to establish tautomeric configuration, conformation, and, to resolve self-sorted speciation.


Asunto(s)
Hidrógeno , Enlace de Hidrógeno , Espectroscopía de Resonancia Magnética/métodos , Conformación Proteica
16.
Nanomaterials (Basel) ; 12(15)2022 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-35893513

RESUMEN

Plasmonic nanostructures, featuring near infrared (NIR)-absorption, are rising as efficient nanosystems for in vitro photothermal (PT) studies and in vivo PT treatment of cancer diseases. Among the different materials, new plasmonic nanostructures based on Cu2-xS nanocrystals (NCs) are emerging as valuable alternatives to Au nanorods, nanostars and nanoshells, largely exploited as NIR absorbing nanoheaters. Even though Cu2-xS plasmonic properties are not linked to geometry, the role played by their size, shape and surface chemistry is expected to be fundamental for an efficient PT process. Here, Cu2-xS NCs coated with a hydrophilic mesoporous silica shell (MSS) are synthesized by solution-phase strategies, tuning the core geometry, MSS thickness and texture. Besides their loading capability, the silica shell has been widely reported to provide a more robust plasmonic core protection than organic molecular/polymeric coatings, and improved heat flow from the NC to the environment due to a reduced interfacial thermal resistance and direct electron-phonon coupling through the interface. Systematic structural and morphological analysis of the core-shell nanoparticles and an in-depth thermoplasmonic characterization by using a pump beam 808 nm laser, are carried out. The results suggest that large triangular nanoplates (NPLs) coated by a few tens of nanometers thick MSS, show good photostability under laser light irradiation and provide a temperature increase above 38 °C and a 20% PT efficiency upon short irradiation time (60 s) at 6 W/cm2 power density.

17.
ACS Appl Bio Mater ; 5(7): 3219-3229, 2022 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-35729847

RESUMEN

Biobased composites with peculiar properties offer an attractive route for producing environmentally friendly materials. The reinforcement for poly(butylene adipate-co-terephthalate) (PBAT), based on zein-titanium dioxide (TiO2) complex (ZTC) microparticles, is presented and used to produce composite filaments, successfully 3-dimensionally (3D) printed by fused deposition modeling (FDM). The outcome of ZTC addition, ranging from 5 to 40 wt %, on the thermo-mechanical properties of composite materials was analyzed. Results reveal that storage modulus increased with increasing the ZTC content, leading to a slight increase in the glass transition temperature. The creep compliance varies with the ZTC concentration, denoting a better resistance to deformation under constant stress conditions for composites with higher complex content. Scanning electron microscopy was used to assess the quality of interphase adhesion between PBAT and ZTC, showing good dispersion and distribution of complex microparticles in the polymer matrix. Infrared spectroscopy confirmed the formation of a valid interface due to the formation of hydrogen bonds between filler and polymer matrix. Preliminary tests on the biocompatibility of these materials were also performed, showing no cytotoxic effects on cell viability. Finally, the 3D printability of biobased composites was demonstrated by realizing complex structures with a commercial FDM printer.


Asunto(s)
Poliésteres , Polímeros , Excipientes , Microscopía Electrónica de Rastreo , Poliésteres/química , Polímeros/química , Impresión Tridimensional
18.
Cell Death Dis ; 13(6): 551, 2022 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-35710782

RESUMEN

Genomic studies have identified recurrent somatic alterations in genes involved in DNA methylation and post-translational histone modifications in acute lymphoblastic leukemia (ALL), suggesting new opportunities for therapeutic interventions. In this study, we identified G9a/EHMT2 as a potential target in T-ALL through the intersection of epigenome-centered shRNA and chemical screens. We subsequently validated G9a with low-throughput CRISPR-Cas9-based studies targeting the catalytic G9a SET-domain and the testing of G9a chemical inhibitors in vitro, 3D, and in vivo T-ALL models. Mechanistically we determined that G9a repression promotes lysosomal biogenesis and autophagic degradation associated with the suppression of sestrin2 (SESN2) and inhibition of glycogen synthase kinase-3 (GSK-3), suggesting that in T-ALL glycolytic dependent pathways are at least in part under epigenetic control. Thus, targeting G9a represents a strategy to exhaust the metabolic requirement of T-ALL cells.


Asunto(s)
N-Metiltransferasa de Histona-Lisina , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Metilación de ADN/genética , Glucógeno Sintasa Quinasa 3/metabolismo , Antígenos de Histocompatibilidad/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Humanos , Proteínas Nucleares/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Linfocitos T/metabolismo
19.
Nutrients ; 14(6)2022 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-35334792

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is a multifactorial condition characterized from hypertriglyceridemia and hepatic fat accumulation, in the absence of alcohol intake. NAFLD starts as steatosis (NAFL), and the continued injury relative to the toxic fat induces inflammation, steatohepatitis (NASH), and HCC. One of the factors determining liver degeneration during the evolution of NAFLD is a modification of Wnt/Frizzled (FZD) signaling. In particular, an inhibition of Wnt signaling and an overexpression of a specific FZD receptor protein, namely, the FZD7, have been observed in NAFLD. Actually, the prognosis and the follow-up of NAFLD is not easy, and the liver biopsy is the gold standard for an accurate detection of liver fibrosis. In this study, the modulation of the FZD7 expression levels in plasma-derived exosomes of NAFLD-affected patients, before and after specific lifestyle interventions, were experimentally evaluated by Western blotting analysis. The experimental data were analyzed by an accurate statistical study that indicated, in the exosomes derived from plasma of NAFLD patients with moderate or severe steatosis, an average expression level of FZD7 that was significantly higher than healthy subjects at baseline; conversely, the values were normalized after 90 days of specific lifestyle interventions. The overall results suggested that the FZD7 delivered by exosomes represents a good candidate as a new and effective biomarker for diagnosis and prognosis of NAFLD.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Enfermedad del Hígado Graso no Alcohólico , Humanos , Estilo de Vida , Enfermedad del Hígado Graso no Alcohólico/patología
20.
ACS Chem Neurosci ; 12(22): 4286-4301, 2021 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-34726377

RESUMEN

Human immunodeficiency virus (HIV) can independently replicate in the central nervous system (CNS) causing neurocognitive impairment even in subjects with suppressed plasma viral load. The antiretroviral drug darunavir (DRV) has been approved for therapy of HIV-infected patients, but its efficacy in the treatment of HIV-associated neurological disorders (HAND) is limited due to the low penetration through the blood-brain barrier (BBB). Therefore, innovations in DRV formulations, based on its encapsulation in optically traceable nanoparticles (NPs), may improve its transport through the BBB, providing, at the same time, optical monitoring of drug delivery within the CNS. The aim of this study was to synthesize biodegradable polymeric NPs loaded with DRV and luminescent, nontoxic carbon dots (C-Dots) and investigate their ability to permeate through an artificial BBB and to inhibit in vitro matrix metalloproteinase-9 (MMP-9) that represents a factor responsible for the development of HIV-related neurological disorders. Biodegradable poly(lactic-co-glycolic) acid (PLGA)-based nanoformulations resulted characterized by an average hydrodynamic size less than 150 nm, relevant colloidal stability in aqueous medium, satisfactory drug encapsulation efficiency, and retained emitting optical properties in the visible region of the electromagnetic spectrum. The assay on the BBB artificial model showed that a larger amount of DRV was able to cross BBB when incorporated in the PLGA NPs and to exert an enhanced inhibition of matrix metalloproteinase-9 (MMP-9) expression levels with respect to free DRV. The overall results reveal the great potential of this class of nanovectors of DRV for an efficacious treatment of HANDs.


Asunto(s)
Infecciones por VIH , Nanopartículas , Enfermedades del Sistema Nervioso , Encéfalo , Darunavir , Infecciones por VIH/tratamiento farmacológico , Humanos , Metaloproteinasa 9 de la Matriz
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