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1.
Nanomedicine ; 54: 102710, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37734452

RESUMEN

Self-assembled multivalent DNA nanocages are an emerging class of molecules useful for biomedicine applications. Here, we investigated the molecular mechanisms of cytotoxicity induced by AS1411 free aptamer, AS1411-linked nanocages (Apt-NCs) and nanocages harboring both folate and AS1411 functionalization (Fol-Apt-NCs) in HeLa and MDA-MB-231 cancer cell lines. The three treatments showed different cytotoxic efficacy and Fol-Apt-NCs resulted the most effective in inhibiting cell proliferation and inducing apoptotic pathways and ROS activation in both HeLa and MDA-MB-231 cells. RNA-seq analysis allowed to identify biological functions and genes altered by the various treatments, depending on the AS1411 route of intracellular entry, highlighting the different behavior of the two cancer cell lines. Notably, Fol-Apt-NCs altered the expression of a subset of genes associated to cancer chemoresistance in MDA-MB-231, but not in HeLa cells, and this may explain the increased chemosensitivity to drugs delivered through DNA nanocages of the triple-negative breast cancer cells.


Asunto(s)
Antineoplásicos , Aptámeros de Nucleótidos , Neoplasias , Humanos , Células HeLa , Ácido Fólico , Antineoplásicos/farmacología , Antineoplásicos/metabolismo , Oligodesoxirribonucleótidos/farmacología , Aptámeros de Nucleótidos/farmacología , ADN , Línea Celular Tumoral
2.
Int J Mol Sci ; 24(15)2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37569803

RESUMEN

Tea Tree Oil (TTO) is an essential oil obtained from the distillation of Melaleuca alternifolia leaves and branches. Due to its beneficial properties, TTO is widely used as an active ingredient in antimicrobial preparations for topical use or in cosmetic products and contains about 100 different compounds, with terpinen-4-ol, γ-terpinene and 1,8-cineole (or eucalyptol) being the molecules most responsible for its biological activities. In this work, the antimicrobial activity of whole TTO and these three major components was evaluated in vitro against fungi, bacteria and viruses. Molecular dynamics simulations were carried out on a bacterial membrane model and a Coxsackievirus B4 viral capsid, to propose an atomistic explanation of their mechanism of action. The obtained results indicate that the strong antimicrobial activity of TTO is attributable to the induction of an altered membrane functionality, mediated by the incorporation of its components within the lipid bilayer, and to a possible ability of the compounds to bind and alter the structural properties of the viral capsid.

3.
Int J Mol Sci ; 21(1)2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31861821

RESUMEN

A computational and experimental integrated approach was applied in order to study the effect of engineering four DNA hairpins into an octahedral truncated DNA nanocage, to obtain a nanostructure able to recognize and bind specific oligonucleotide sequences. Modeling and classical molecular dynamics simulations show that the new H4-DNA nanocage maintains a stable conformation with the closed hairpins and, when bound to complementary oligonucleotides produces an opened conformation that is even more stable due to the larger hydrogen bond number between the hairpins and the oligonucleotides. The internal volume of the open conformation is much larger than the closed one, switching from 370 to 650 nm3, and the predicted larger conformational change is experimentally detectable by gel electrophoresis. H4-DNA nanocages display high stability in serum, can efficiently enter the cells where they are stable and maintain the ability to bind, and sequester an intracellular-specific oligonucleotide. Moreover, H4-DNA nanocages, modified in order to recognize the oncogenic miR21, are able to seize miRNA molecules inside cells in a selective manner.


Asunto(s)
ADN/química , ADN/farmacología , Silenciador del Gen , MicroARNs/genética , Células HeLa , Humanos , Simulación de Dinámica Molecular , Nanoestructuras/química , Conformación de Ácido Nucleico
4.
Biochim Biophys Acta Mol Basis Dis ; 1864(2): 509-519, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29154925

RESUMEN

Amyotrophic Lateral Sclerosis (ALS) is a chronic neurodegenerative disease affecting upper and lower motor neurons, with unknown aetiology. Lipid rafts, cholesterol enriched microdomains of the plasma membrane, have been linked to neurodegenerative disorders like ALS. The NMDA-receptor subcellular localization in lipid rafts is known to play many roles, from modulating memory strength to neurotoxicity. In this study, performed on the widely used G93A mouse model of ALS, we have shown an equal content of total membrane cholesterol in Control and G93A cortical cultures. Moreover, by electrophysiological studies, we have recorded NMDA- and AMPA-evoked currents which were not significantly different between the two neuronal populations. To study the role of membrane cholesterol on glutamate receptor functionality, we have analysed NMDA and AMPA receptors following cholesterol membrane depletion by methyl-ß-cyclodextrin (MßCD). Interestingly, MßCD chronic treatment has provoked a significant reduction of NMDA-evoked currents in both cellular populations which was dose- and time-dependent but significantly higher in ALS neurons compared to Control. The different MßCD effect on NMDA-evoked currents was not due to a different membrane receptor subunit composition but seemed to cause in both neuronal populations a NMDA receptor membrane redistribution. MßCD treatment effect was receptor-specific since no alterations in the two neuronal populations were detected on AMPA receptors. These results lead us to speculate for an altered proteomic composition of lipid rafts in cortical mutated neurons and suggest the need for further studies on the lipid rafts composition and on their interaction with membrane receptors in ALS cortices.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Colesterol/metabolismo , Microdominios de Membrana/química , Neuronas Motoras/citología , N-Metilaspartato/farmacología , Receptores de N-Metil-D-Aspartato/metabolismo , Animales , Membrana Celular/metabolismo , Supervivencia Celular , Modelos Animales de Enfermedad , Electrofisiología , Femenino , Ácido Glutámico/metabolismo , Humanos , Masculino , Ratones , Ratones Transgénicos , Neuronas Motoras/metabolismo , Proteómica , Receptores AMPA/metabolismo , Transducción de Señal , Superóxido Dismutasa-1/genética , beta-Ciclodextrinas/farmacología
5.
Nanomedicine ; 14(4): 1181-1190, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29458213

RESUMEN

Selective targeting is a crucial property of nanocarriers used for drug delivery in cancer therapy. We generated biotinylated octahedral DNA nanocages functionalized with folic acid through bio-orthogonal conjugation chemistry. Molecular modelling indicated that a distance of about 2.5 nm between folic acid and DNA nanocage avoids steric hindrance with the folate receptor. HeLa cells, a folate receptor positive tumour cell line, internalize folate-DNA nanocages with efficiency greater than 40 times compared to cells not expressing the folate receptors. Functionalized DNA nanocages are highly stable, not cytotoxic and can be efficiently loaded with the chemotherapeutic agent doxorubicin. After entry into cells, doxorubicin-loaded nanoparticles are confined in vesicular structures, indicating that DNA nanocages traffic through the endocytic pathway. Doxorubicin release from loaded DNA cages, facilitated by low pH of endocytic vesicles, induces toxic pathways that, besides selectively killing folate receptor-positive cancer cells, leads to cage degradation avoiding nanoparticles accumulation inside cells.


Asunto(s)
Aductos de ADN/química , ADN/química , Doxorrubicina/química , Sistemas de Liberación de Medicamentos/métodos , Ácido Fólico/química , Nanopartículas/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Aductos de ADN/farmacología , Doxorrubicina/farmacología , Células HT29 , Células HeLa , Humanos
6.
Exp Cell Res ; 338(1): 70-81, 2015 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-26364738

RESUMEN

Diverting a protein from its intracellular location is a unique property of intrabodies. To interfere with the intracellular traffic of heterochromatin protein 1ß (HP1ß) in living cells, we have generated a cytoplasmic targeted anti-HP1ß intrabody, specifically directed against the C-terminal portion of the molecule. HP1ß is a conserved component of mouse and human constitutive heterochromatin involved in diverse nuclear functions including gene silencing, DNA repair and nuclear membrane assembly. We found that the anti-HP1ß intrabody sequesters HP1ß into cytoplasmic aggregates, inhibiting its traffic to the nucleus. Lamin B receptor (LBR) and a subset of core histones (H3/H4) are also specifically co-sequestered in the cytoplasm of anti-HP1ß intrabody-expressing cells. Methylated histone H3 at K9 (Me9H3), a marker of constitutive heterochromatin, is not affected by the anti-HP1ß intrabody expression. Hyper-acetylating conditions completely dislodge H3 from HP1ß:LBR containing aggregates. The expression of anti-HP1ß scFv fragments induces apoptosis, associated with an alteration of nuclear morphology. Both these phenotypes are specifically rescued either by overexpression of recombinant full length HP1ß or by HP1ß mutant containing the chromoshadow domain, but not by recombinant LBR protein. The HP1ß-chromodomain mutant, on the other hand, does not rescue the phenotypes, but does compete with LBR for binding to HP1ß. These findings provide new insights into the mode of action of cytoplasmic-targeted intrabodies and the interaction between HP1ß and its binding partners involved in peripheral heterochromatin organisation.


Asunto(s)
Proteínas Cromosómicas no Histona/metabolismo , Citoplasma/metabolismo , Histonas/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Anticuerpos de Cadena Única/metabolismo , Secuencia de Aminoácidos , Animales , Forma del Núcleo Celular , Homólogo de la Proteína Chromobox 5 , Proteínas Cromosómicas no Histona/química , Células HeLa , Humanos , Ratones , Datos de Secuencia Molecular , Células 3T3 NIH , Agregado de Proteínas , Dominios y Motivos de Interacción de Proteínas , Transporte de Proteínas , Receptores Citoplasmáticos y Nucleares/química , Receptor de Lamina B
7.
Microorganisms ; 12(8)2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39203361

RESUMEN

Apical periodontitis is an inflammatory disease triggered by oral pathogens invading necrotic root canals. The aim of this study was to evaluate the coronal and root canal bacterial community profiles in primary endodontic infections with different periapical (PAI) indices in comparison to oral mucosa controls. A total of 31 patients with primary apical periodontitis, 14 with PAI-1 and 17 with PAI-3 were recruited. Microbial specimens from mucosa (control samples) and endodontic necrotic tissues were collected in each patient. Microbiota composition was studied through 16S ribosomal RNA gene amplicon sequencing analysis. Overall, 2953 taxa from 168 different genera of 451 various microbial species were retrieved in the controls and PAI-1 and PAI-3 groups. Firmicutes is the predominant phylum in the oral controls (34.5%) and PAI-1 (44.4%) groups, while Bacteroidetes is predominant in PAI-3 (38.6%). The Proteobacteria (21.5%) and Fusobacteria (12.5%) relative abundance is higher in oral controls while that of Synergistetes is higher in the PAI-1 (3.5%) and PAI-3 (2.5%) groups, being almost absent in controls (less than 0.1%). Most of the increased bacterial species found in the PAI groups were strict anaerobes. A diminished microbial diversity was found in apical periodontitis with higher PAI. These samples were also characterized by an increase in bacteria belonging to phyla and genera with an increased anaerobic character.

8.
Biochem Biophys Res Commun ; 438(2): 340-5, 2013 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-23892036

RESUMEN

The lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), the major receptor for oxidized low-density lipoprotein (ox-LDL) in endothelial cells, is overexpressed in atherosclerotic lesions. LOX-1 specific inhibitors, urgently necessary to reduce the rate of atherosclerotic and inflammation processes, are not yet available. We have designed and synthesized a new modified oxidized phospholipid, named PLAzPC, which plays to small scale the ligand-receptor recognition scheme. Molecular docking simulations confirm that PLAzPC disables the hydrophobic component of the ox-LDL recognition domain and allows the interaction of the l-lysine backbone charged groups with the solvent and with the charged/polar residues located around the edges of the LOX-1 hydrophobic tunnel. Binding assays, in a cell model system expressing human LOX-1 receptors, confirm that PLAzPC markedly inhibits ox-LDL binding to LOX-1 with higher efficacy compared to previously identified inhibitors.


Asunto(s)
Fosfolípidos/química , Receptores Depuradores de Clase E/antagonistas & inhibidores , Animales , Aterosclerosis/metabolismo , Células COS , Chlorocebus aethiops , ADN/química , Diseño de Fármacos , Endotelio Vascular/metabolismo , Humanos , Ligandos , Lisina/química , Simulación del Acoplamiento Molecular , Oxígeno/química , Unión Proteica , Conformación Proteica , Especificidad por Sustrato
9.
Arch Biochem Biophys ; 540(1-2): 9-18, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24113299

RESUMEN

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a scavenger receptor that mediates the recognition, the binding and internalization of ox-LDL. A truncated soluble form of LOX-1 (sLOX-1) has been identified that, at elevated levels, has been associated to acute coronary syndrome. Human sLOX-1 is the extracellular part of membrane LOX-1 which is cleaved in the NECK domain with a mechanism that has not yet been identified. Purification of human sLOX-1 has been carried out to experimentally identify the cleavage site region within the NECK domain. Molecular modelling and classical molecular dynamics simulation techniques have been used to characterize the structural and dynamical properties of the LOX-1 NECK domain in the presence and absence of the CTLD recognition region, taking into account the obtained proteolysis results. The simulative data indicate that the NECK domain is stabilized by the coiled-coil heptad repeat motif along the simulations, shows a definite flexibility pattern and is characterized by specific electrostatic potentials. The detection of a mobile inter-helix space suggests an explanation for the in vivo susceptibility of the NECK domain to the proteolytic cleavage, validating the assumption that the NECK domain sequence is composed of a coiled-coil motif destabilized in specific regions of functional significance.


Asunto(s)
Modelos Moleculares , Proteolisis , Receptores Depuradores de Clase E/química , Receptores Depuradores de Clase E/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Humanos , Enlace de Hidrógeno , Espectrometría de Masas , Datos de Secuencia Molecular , Estabilidad Proteica , Estructura Terciaria de Proteína , Reproducibilidad de los Resultados , Solubilidad , Solventes/química , Electricidad Estática , Propiedades de Superficie
10.
Mol Pharmacol ; 82(2): 246-54, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22570368

RESUMEN

Lectin-like oxidized low-density lipoprotein (LOX-1), the primary receptor for oxidized low-density lipoprotein (ox-LDL) in endothelial cells, is up-regulated in atherosclerotic lesions. Statins are the principal therapeutic agents for cardiovascular diseases and are known to down-regulate LOX-1 expression. Whether the effect on the LOX-1 receptor is related to statin-mediated cholesterol-lowering activity is unknown. We investigate the requirement of cholesterol for LOX-1-mediated lipid particle internalization, trafficking, and processing and the role of statins as inhibitors of LOX-1 function. Disruption of cholesterol-rich membrane microdomains by acute exposure of cells to methyl-ß-cyclodextrin or chronic exposure to different statins (lovastatin and atorvastatin) led to a spatial disorganization of LOX-1 in plasma membranes and a marked loss of specific LOX-1 function in terms of ox-LDL binding and internalization. Subcellular fractionation and immunochemical studies indicate that LOX-1 is naturally present in caveolae-enriched lipid rafts and, by cholesterol reduction, the amount of LOX-1 in this fraction is highly decreased (≥60%). In contrast, isoprenylation inhibition had no effect on the distribution and function of LOX-1 receptors. Furthermore, in primary cultures from atherosclerotic human aorta lesions, we confirm the presence of LOX-1 in caveolae-enriched lipid rafts and demonstrate that lovastatin treatment led to down-regulation of LOX-1 in lipid rafts and rescue of the ox-LDL-induced apoptotic phenotype. Taken together, our data reveal a previously unrecognized essential role of membrane cholesterol for LOX-1 receptor activity and suggest that statins protect vascular endothelium against the adverse effect of ox-LDL by disruption of membrane rafts and impairment of LOX-1 receptor function.


Asunto(s)
Anticolesterolemiantes/farmacología , Colesterol/fisiología , Microdominios de Membrana/efectos de los fármacos , Microdominios de Membrana/patología , Receptores Depuradores de Clase E/antagonistas & inhibidores , Receptores Depuradores de Clase E/fisiología , Animales , Células COS , Células Cultivadas , Chlorocebus aethiops , Colesterol/deficiencia , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/patología , Endotelio Vascular/fisiología , Humanos , Microdominios de Membrana/metabolismo
11.
Blood ; 115(8): 1554-63, 2010 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-20009034

RESUMEN

The identification of molecules responsible for apoptotic cell (AC) uptake by dendritic cells (DCs) and induction of T-cell immunity against AC-associated antigens is a challenge in immunology. DCs differentiated in the presence of interferon-alpha (IFN-alpha-conditioned DCs) exhibit a marked phagocytic activity and a special attitude in inducing CD8(+) T-cell response. In this study, we found marked overexpression of the scavenger receptor oxidized low-density lipoprotein receptor 1 (LOX-1) in IFN-alpha-conditioned DCs, which was associated with increased levels of genes belonging to immune response families and high competence in inducing T-cell immunity against antigens derived from allogeneic apoptotic lymphocytes. In particular, the capture of ACs by IFN-alpha DCs led to a substantial subcellular rearrangement of major histocompatibility complex class I and class II molecules, along with enhanced cross-priming of autologous CD8(+) T cells and CD4(+) T-cell activation. Remarkably, AC uptake, CD8(+) T-cell cross-priming, and, to a lesser extent, priming of CD4(+) T lymphocytes were inhibited by a neutralizing antibody to the scavenger receptor LOX-1 protein. These results unravel a novel LOX-1-dependent pathway by which IFN-alpha can, under both physiologic and pathologic conditions, render DCs fully competent for presenting AC-associated antigens for cross-priming CD8(+) effector T cells, concomitantly with CD4(+) T helper cell activation.


Asunto(s)
Presentación de Antígeno/inmunología , Apoptosis/efectos de los fármacos , Células Dendríticas/inmunología , Factores Inmunológicos/farmacología , Interferón-alfa/farmacología , Receptores Depuradores de Clase E/inmunología , Transducción de Señal/efectos de los fármacos , Apoptosis/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Células Cultivadas , Humanos , Inmunidad Celular/efectos de los fármacos , Factores Inmunológicos/inmunología , Interferón-alfa/inmunología , Activación de Linfocitos/efectos de los fármacos , Transducción de Señal/inmunología
12.
Pharmaceutics ; 14(12)2022 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-36559104

RESUMEN

DNA is an excellent programmable polymer for the generation of self-assembled multivalent nanostructures useful for biomedical applications. Herein, we developed (i) folate-functionalized nanocages (Fol-NC), very efficiently internalized by tumor cells overexpressing the α isoform of the folate receptor; (ii) AS1411-linked nanocages (Apt-NC), internalized through nucleolin, a protein overexpressed in the cell surface of many types of cancers; and (iii) nanostructures that harbor both folate and AS1411 aptamer functionalization (Fol-Apt-NC). We analyzed the specific miRNA silencing activity of all types of nanostructures harboring miRNA sequestering sequences complementary to miR-21 and the cytotoxic effect when loaded with doxorubicin in a drug-resistant triple-negative breast cancer cell line. We demonstrate that the presence of folate as a targeting ligand increases the efficiency in miR-21 silencing compared to nanocages functionalized with AS1411. Double-functionalized nanocages (Fol-Apt-NC), loaded with doxorubicin, resulted in an increase of over 51% of the cytotoxic effect on MDA-MB-231 cells compared to free doxorubicin, demonstrating, besides selectivity, the ability of nanocages to overcome Dox chemoresistance. The higher efficiency of the folate-functionalized nanocages is due to the way of entrance, which induces more than four times higher intracellular stability and indicates that the folate-mediated route of cell entry is more efficient than the nucleolin-mediated one when both folate and AS1411 modifications are present.

13.
Nutrients ; 14(2)2022 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-35057440

RESUMEN

Intestinal dysbiosis has been widely documented in inflammatory bowel diseases (IBDs) and is thought to influence the onset and perpetuation of gut inflammation. However, it remains unclear whether such bacterial changes rely in part on the modification of an IBD-associated lifestyle (e.g., smoking and physical activity) and diet (e.g., rich in dairy products, cereals, meat and vegetables). In this study, we investigated the impact of these habits, which we defined as confounders and covariates, on the modulation of intestinal taxa abundance and diversity in IBD patients. 16S rRNA gene sequence analysis was performed using genomic DNA extracted from the faecal samples of 52 patients with Crohn's disease (CD) and 58 with ulcerative colitis (UC), which are the two main types of IBD, as well as 42 healthy controls (HC). A reduced microbial diversity was documented in the IBD patients compared with the HC. Moreover, we identified specific confounders and covariates that influenced the association between some bacterial taxa and disease extent (in UC patients) or behaviour (in CD patients) compared with the HC. In particular, a PERMANOVA stepwise regression identified the variables "age", "eat yogurt at least four days per week" and "eat dairy products at least 4 days per week" as covariates when comparing the HC and patients affected by ulcerative proctitis (E1), left-sided UC (distal UC) (E2) and extensive UC (pancolitis) (E3). Instead, the variables "age", "gender", "eat meat at least four days per week" and "eat bread at least 4 days per week" were considered as covariates when comparing the HC with the CD patients affected by non-stricturing, non-penetrating (B1), stricturing (B2) and penetrating (B3) diseases. Considering such variables, our analysis indicated that the UC extent differentially modulated the abundance of the Bifidobacteriaceae, Rikenellaceae, Christensenellaceae, Marinifilaceae, Desulfovibrionaceae, Lactobacillaceae, Streptococcaceae and Peptostreptococcaceae families, while the CD behaviour influenced the abundance of Christensenellaceae, Marinifilaceae, Rikenellaceae, Ruminococcaceae, Barnesiellaceae and Coriobacteriaceae families. In conclusion, our study indicated that some covariates and confounders related to an IBD-associated lifestyle and dietary habits influenced the intestinal taxa diversity and relative abundance in the CD and UC patients compared with the HC. Indeed, such variables should be identified and excluded from the analysis to characterize the bacterial families whose abundance is directly modulated by IBD status, as well as disease extent or behaviour.


Asunto(s)
Colitis Ulcerosa/microbiología , Enfermedad de Crohn/microbiología , Dieta , Disbiosis/microbiología , Microbioma Gastrointestinal , Estilo de Vida , Adulto , Factores de Edad , Anciano , Estudios de Casos y Controles , Productos Lácteos , Ejercicio Físico , Heces/microbiología , Humanos , Persona de Mediana Edad , ARN Ribosómico 16S/genética , Factores Sexuales , Fumar , Yogur , Adulto Joven
14.
Pharmaceutics ; 13(10)2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34683964

RESUMEN

The nucleolin-binding G-quadruplex AS1411 aptamer has been widely used for cancer therapy and diagnosis and linked to nanoparticles for its selective targeting activity. We applied a computational and experimental integrated approach to study the effect of engineering AS1411 aptamer on an octahedral truncated DNA nanocage to obtain a nanostructure able to combine selective cancer-targeting and anti-tumor activity. The nanocages functionalized with one aptamer molecule (Apt-NC) displayed high stability in serum, were rapidly and selectively internalized in cancer cells through an AS1411-dependent mechanism, and showed over 200-fold increase in anti-cancer activity when compared with the free aptamer. Comparison of Apt-NCs and free AS1411 intracellular distribution showed that they traffic differently inside cells: Apt-NCs distributed through the endo-lysosomal pathway and were never found in the nuclei, while the free AS1411 was mostly found in the perinuclear region and in nucleoli. Molecular dynamics simulations indicated that the aptamer, when linked to the nanocage, sampled a limited conformational space, more confined than in the free state, which is characterized by a large number of metastable conformations. A different intracellular trafficking of Apt-NCs compared with free aptamer and the confined aptamer conformations induced by the nanocage were likely correlated with the high cytotoxic enhancement, suggesting a structure-function relationship for the AS1411 aptamer activity.

15.
Cell Death Dis ; 12(1): 7, 2021 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-33414439

RESUMEN

MicroRNAs play an important role in tumorigenesis and, among them, miR-21 is found to be aberrantly up-regulated in various tumors. The tumor-associated antigen, folate receptor alpha is a GPI-membrane protein overexpressed in many malignant tumors of epithelial origin, including ovarian and cervical cancers. Covalently bound octahedral DNA nanocages were functionalized with folate molecules and utilized as scaffolds to engineer four sequestering units with a miR-21 complementary sequence for obtaining biocompatible Fol-miR21-NC non-toxic nanostructures, to be able to selectively recognize folate receptor alpha-overexpressing cancer cells and sequester the oncogenic miR-21. qPCR assays showed that Fol-miR21-NCs reduce the miR-21 expression up to 80% in cancer cells in the first 2 days of treatment. Functional assays demonstrated that miR-21 sequestering leads to up-regulation of miR-21 tumor suppressor targets (i.e., PTEN and Pdcd4), reduction in cancer cell migration, reduction in proliferation, and increase in cell death. Fol-miR21-NCs can be efficiently loaded with the chemotherapeutic agent doxorubicin. Co-delivery of anti-miR-21 and doxorubicin showed additive cytotoxic effects on tumor cells, paving the way for their use as selective nucleic acid drugs.


Asunto(s)
ADN/genética , Doxorrubicina/uso terapéutico , MicroARNs/metabolismo , Neoplasias/tratamiento farmacológico , Doxorrubicina/farmacología , Células HeLa , Humanos , Nanoestructuras
16.
Brain Sci ; 10(4)2020 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-32325848

RESUMEN

The involvement of the gut microbiota in Parkinson's disease (PD), investigated in several studies, identified some common alterations of the microbial community, such as a decrease in Lachnospiraceae and an increase in Verrucomicrobiaceae families in PD patients. However, the results of other bacterial families are often contradictory. Machine learning is a promising tool for building predictive models for the classification of biological data, such as those produced in metagenomic studies. We tested three different machine learning algorithms (random forest, neural networks and support vector machines), analyzing 846 metagenomic samples (472 from PD patients and 374 from healthy controls), including our published data and those downloaded from public databases. Prediction performance was evaluated by the area under curve, accuracy, precision, recall and F-score metrics. The random forest algorithm provided the best results. Bacterial families were sorted according to their importance in the classification, and a subset of 22 families has been identified for the prediction of patient status. Although the results are promising, it is necessary to train the algorithm with a larger number of samples in order to increase the accuracy of the procedure.

17.
Trends Mol Med ; 14(9): 373-80, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18693139

RESUMEN

Misfolding diseases are a wide group of devastating disorders characterized by the accumulation of pathological protein aggregates. Although these disorders still lack an effective treatment, new antibody-based strategies are emerging and entering clinical trials. The intrabody approach is a gene-based technology developed to neutralize or modify the function of intracellular and extracellular target antigens. Because intrabodies can potentially target all the different isoforms of a misfolding-prone protein, including pathological conformations, they are emerging as therapeutic molecules for the treatment of misfolding diseases, including Alzheimer's, Parkinson's, Huntington's and prion diseases. This review will provide a description of the intrabody approach, an update of preclinical studies on misfolding diseases and an outlook on the intrabody delivery issue for therapeutic purposes.


Asunto(s)
Anticuerpos/uso terapéutico , Encefalopatías/tratamiento farmacológico , Espacio Intracelular/inmunología , Pliegue de Proteína , Animales , Anticuerpos/administración & dosificación , Encefalopatías/metabolismo , Humanos , Ingeniería de Proteínas
18.
Curr Mol Med ; 8(1): 2-11, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18289010

RESUMEN

Conformational or misfolding diseases are a large class of devastating human disorders associated with protein misfolding and aggregation. Most conformational diseases are caused by a combination of genetic and environmental factors, suggesting that spontaneous events can destabilize the protein involved in the pathology or impair the clearance mechanisms of misfolded aggregates. Aging is one of the risk factors associa-ted to these events, and the clinical relevance of conformational disorders is growing dramatically, as they begin to reach epidemic proportions due to increases in mean lifespan. Currently, there are no effective strategies to slow or prevent these diseases. Intrabodies are promising therapeutic agents for the treatment of misfolding diseases, because of their virtually infinite ability to specifically recognize the different conformations of a protein, including pathological isoforms, and because they can be targeted to the potential sites of aggregation (both intra- and extracellular sites). These molecules can work as neutralizing agents against amylo-idogenic proteins by preventing their aggregation, and/or as molecular shunters of intracellular traffic by re-routing the protein from its potential aggregation site. The fast-developing field of recombinant antibody technology provides intrabodies with enhanced binding specificity and stability, together with lower immunogenicity, for use in a clinical setting. This review provides an update on the applications of intrabodies in misfolding diseases, with particular emphasis on an evaluation of their multiple and feasible modes of action.


Asunto(s)
Anticuerpos/metabolismo , Conformación Proteica , Pliegue de Proteína , Transporte de Proteínas/fisiología , Humanos , Ingeniería de Proteínas
19.
Parkinsonism Relat Disord ; 65: 124-130, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31174953

RESUMEN

INTRODUCTION: In recent years the hypothesis that gut microbiota associates with Parkinson's disease (PD) has gained importance, although it has not been possible to define a specific microbiota composition as a predictive biomarker of this disease. We have investigated dysbiosis of gut microbiota in a selected population of PD patients from Central Italy, and examined the weight of specific confounders and predictors, in order to identify potential correlations with clinical phenotypes. METHODS: 152 fecal samples were collected from 80 patients and 72 healthy controls. Patients were enrolled according to tight inclusion criteria. Microbiota composition was studied through 16s ribosomal RNA gene amplicon sequencing analysis in combination with data on dietary/life habits. Age, loss of weight, and sex were recognized as confounding factors, whereas PD-status, age, Body Mass Index, "eat cereals", "gain of weigth" and "physical activity" as predictors. The presence of Lactobacillaceae, Enterobacteriaceae and Enterococcaceae families was significantly higher in feces from PD patients compared to healthy controls, while Lachnospiraceae were significantly reduced. Lower levels of Lachnospiraceae and higher levels of Enterobacteriaceae families also correlated with increased disease severity and motor impairment (Hoehn & Yahr stage, MDS-UPDRS Part III). Predictive metagenomics indicated a significant variation of genes involved in the metabolism of short chain fatty acids and amino acids, and in lipopolysaccharide biosynthesis. CONCLUSIONS: PD showed a distinctive microbiota composition. Functional predictions suggest changes in pathways favoring a pro-inflammatory environment in the gastrointestinal tract, and a reduction in the biosynthesis of amino acids acting as precursors of physiological transmitters.


Asunto(s)
Disbiosis/diagnóstico , Microbioma Gastrointestinal/fisiología , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/microbiología , Anciano , Disbiosis/fisiopatología , Heces/microbiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/fisiopatología
20.
Nanoscale ; 11(22): 10808-10818, 2019 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-31134260

RESUMEN

DNA nanostructures with different sizes and shapes, assembled through either covalent or non-covalent bonds, namely tetrahedral and octahedral nanocages, rod-shaped chainmails, square box and rectangular DNA origami structures, were compared for their stability in serum, cell surface binding, internalization efficiency, and intracellular degradation rate. For cell internalization a specific cell system, highly expressing the scavenger receptor LOX-1 was used. The results indicate that LOX-1 binds and internalizes a broad family of DNA structures of different sizes that, however, have a different fate and lifetime inside the cells. Covalently linked tetrahedra, octahedra or chainmails are intact inside cells for up to 18 hours whilst the same DNA nanostructures without covalent bonds along with square box and rectangular origami are rapidly degraded. These data suggest that non-covalently linked structures may be useful for fast drug release whilst the covalently-linked structures could be appropriate vehicles for slow release of molecules.


Asunto(s)
ADN , Nanoestructuras/química , Conformación de Ácido Nucleico , Receptores Depuradores de Clase E/metabolismo , Animales , Células COS , Chlorocebus aethiops , ADN/química , ADN/farmacocinética
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