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1.
Genes Dev ; 34(17-18): 1161-1176, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32820036

RESUMEN

Medulloblastoma is a malignant childhood brain tumor arising from the developing cerebellum. In Sonic Hedgehog (SHH) subgroup medulloblastoma, aberrant activation of SHH signaling causes increased proliferation of granule neuron progenitors (GNPs), and predisposes these cells to tumorigenesis. A second, cooperating genetic hit is often required to push these hyperplastic cells to malignancy and confer mutation-specific characteristics associated with oncogenic signaling. Somatic loss-of-function mutations of the transcriptional corepressor BCOR are recurrent and enriched in SHH medulloblastoma. To investigate BCOR as a putative tumor suppressor, we used a genetically engineered mouse model to delete exons 9/10 of Bcor (BcorΔE9-10 ) in GNPs during development. This mutation leads to reduced expression of C-terminally truncated BCOR (BCORΔE9-10). While BcorΔE9-10 alone did not promote tumorigenesis or affect GNP differentiation, BcorΔE9-10 combined with loss of the SHH receptor gene Ptch1 resulted in fully penetrant medulloblastomas. In Ptch1+/- ;BcorΔE9-10 tumors, the growth factor gene Igf2 was aberrantly up-regulated, and ectopic Igf2 overexpression was sufficient to drive tumorigenesis in Ptch1+/- GNPs. BCOR directly regulates Igf2, likely through the PRC1.1 complex; the repressive histone mark H2AK119Ub is decreased at the Igf2 promoter in Ptch1+/- ;BcorΔE9-10 tumors. Overall, our data suggests that BCOR-PRC1.1 disruption leads to Igf2 overexpression, which transforms preneoplastic cells to malignant tumors.


Asunto(s)
Neoplasias Cerebelosas/genética , Regulación Neoplásica de la Expresión Génica/genética , Proteínas Hedgehog/metabolismo , Meduloblastoma/genética , Proteínas del Grupo Polycomb/metabolismo , Proteínas Represoras/genética , Animales , Carcinogénesis/genética , Modelos Animales de Enfermedad , Proteínas Hedgehog/genética , Humanos , Ratones , Mutación , Receptor Patched-1/genética , Proteínas del Grupo Polycomb/genética , Proteínas Represoras/metabolismo , Eliminación de Secuencia
2.
Waste Manag Res ; : 734242X241227370, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38380635

RESUMEN

Construction and demolition waste (CDW) worldwide generation accounts 10 billion tonnes yearly. The major fraction is landfilled requiring innovative recycling methods to reduce the associated environmental impacts and to increase its circularity. Our study demonstrated the feasibility of using different CDW fines to develop recycled cements and optimized the content of CDW recycled cements with well-graded crushed stone (WGCS) for use as pavement base layer. We scaled up the study obtaining CDW cement and aggregates from a local recycling plant, as well as pilot pavement sections designed, constructed and field deflections measured. As results, the CDW cement pastes exhibited accumulated heat values of up to 111 J g-1 and achieved a compressive strength of approximately 16 MPa. The unconfined compressive strength and resilient modulus (RM) achieved using CDW cement and WGCS were 2-3 and >3000 MPa, respectively. The sections constructed using CDW cement exhibited intermediate behaviour compared to those obtained using reference materials (6% Portland cement-WGCS and a conventional granular base made using WGCS). The deflection decreased over time owing to the pozzolanic reaction.

3.
Molecules ; 26(18)2021 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-34577145

RESUMEN

Chagas disease (CD) affects more than 6 million people worldwide. The available treatment is far from ideal, creating a demand for new alternative therapies. Botanical diversity provides a wide range of novel potential therapeutic scaffolds. Presently, our aim was to evaluate the mammalian host toxicity and anti-Trypanosoma cruzi activity of botanic natural products including extracts, fractions and purified compounds obtained from Brazilian flora. In this study, 36 samples of extracts and fractions and eight pure compounds obtained from seven plant species were evaluated. The fraction dichloromethane from Aureliana fasciculata var. fasciculata (AFfPD) and the crude extract of Piper tectoniifolium (PTFrE) showed promising trypanosomicidal activity. AFfPD and PTFrE presented EC50 values 10.7 ± 2.8 µg/mL and 12.85 ± 1.52 µg/mL against intracellular forms (Tulahuen strain), respectively. Additionally, both were active upon bloodstream trypomastigotes (Y strain), exhibiting EC50 2.2 ± 1.0 µg/mL and 38.8 ± 2.1 µg/mL for AFfPD and PTFrE, respectively. Importantly, AFfPD is about five-fold more potent than Benznidazole (Bz), the reference drug for CD, also reaching lower EC90 value (7.92 ± 2.2 µg/mL) as compared to Bz (23.3 ± 0.6 µg/mL). Besides, anti-parasitic effect of eight purified botanic substances was also investigated. Aurelianolide A and B (compounds 1 and 2) from A. fasciculata and compound 8 from P. tuberculatum displayed the best trypanosomicidal effect. Compounds 1, 2 and 8 showed EC50 of 4.6 ± 1.3 µM, 1.6 ± 0.4 µM and 8.1 ± 0.9 µM, respectively against intracellular forms. In addition, in silico analysis of these three biomolecules was performed to predict parameters of absorption, distribution, metabolism and excretion. The studied compounds presented similar ADMET profile as Bz, without presenting mutagenicity and hepatotoxicity aspects as predicted for Bz. Our findings indicate that these natural products have promising anti-T. cruzi effect and may represent new scaffolds for future lead optimization.


Asunto(s)
Biodiversidad , Productos Biológicos , Trypanosoma cruzi , Brasil , Simulación por Computador
4.
Biometals ; 32(1): 89-100, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30506342

RESUMEN

Due to their unique and versatile biochemical properties, ruthenium-based compounds have emerged as promising anticancer agents. Previous studies showed that three ruthenium(II) compounds: [Ru(pySH)(bipy)(dppb)]PF6 (1), [Ru(HSpym)(bipy)(dppb)]PF6 (2) and Ru[(SpymMe2)(bipy)(dppb)]PF6 (3) presented anticancer properties higher than doxorubicin and cisplatin and acted as human topoisomerase IB (Topo I) inhibitors. Here, we focused our studies on in vitro intestinal permeability and anticancer mechanisms of these three complexes. Caco-2 permeation studies showed that 1 did not permeate the monolayer of intestinal cells, suggesting a lack of absorption on oral administration, while 2 and 3 permeated the cells after 60 and 120 min, respectively. Complexes 2 and 3 fully inhibited Topo II relaxation activity at 125 µM. In previously studies, 3 was the most potent inhibitor of Topo I, here, we concluded that it is a dual topoisomerase inhibitor. Moreover, it presented selectivity to cancer cells when evaluated by clonogenic assay. Thus, 3 was selected to gene expression assay front MDA-MB-231 cells from triple-negative breast cancer (TNBC), which represents the highly aggressive subgroup of breast cancers with poor prognosis. The analyses revealed changes of 27 out of 84 sought target genes. PARP1 and PARP2 were 5.29 and 1.83 times down-regulated after treatment with 3, respectively. PARPs have been attractive antitumor drug targets, considering PARP inhibition could suppress DNA damage repair and sensitize tumor cells to DNA damage agents. Recent advances in DNA repair studies have shown that an approach that causes cell lethality using synthetic PARP-inhibiting drugs has produced promising results in TNBC.


Asunto(s)
Antineoplásicos/farmacología , Complejos de Coordinación/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Rutenio/farmacología , Inhibidores de Topoisomerasa II/farmacología , Antineoplásicos/química , Células CACO-2 , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Complejos de Coordinación/química , ADN-Topoisomerasas de Tipo II/metabolismo , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Inhibidores de Poli(ADP-Ribosa) Polimerasas/química , Poli(ADP-Ribosa) Polimerasas/metabolismo , Rutenio/química , Relación Estructura-Actividad , Inhibidores de Topoisomerasa II/química
5.
Artículo en Inglés | MEDLINE | ID: mdl-29203486

RESUMEN

Five bis-arylimidamides were assayed as anti-Trypanosoma cruzi agents by in vitro, in silico, and in vivo approaches. None were considered to be pan-assay interference compounds. They had a favorable pharmacokinetic landscape and were active against trypomastigotes and intracellular forms, and in combination with benznidazole, they gave no interaction. The most selective agent (28SMB032) tested in vivo led to a 40% reduction in parasitemia (0.1 mg/kg of body weight/5 days intraperitoneally) but without mortality protection. In silico target fishing suggested DNA as the main target, but ultrastructural data did not match.


Asunto(s)
Amidinas/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Enfermedad de Chagas/tratamiento farmacológico , Masculino , Ratones , Nitroimidazoles/farmacología , Parasitemia/tratamiento farmacológico , Pruebas de Sensibilidad Parasitaria/métodos
6.
Int J Mol Sci ; 17(5)2016 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-27213368

RESUMEN

Cisplatin and its derivatives are the main metallodrugs used in cancer therapy. However, low selectivity, toxicity and drug resistance are associated with their use. The zinc(II) (Zn(II)) thiosemicarbazone complexes [Zn(atc-Et)2] (1) and [Zn(atc-Ph)2] (2) (atc-R: monovalent anion of 2-acetylpyridine N4-R-thiosemicarbazone) were synthesized and fully characterized in the solid state and in solution via elemental analysis, Fourier transform infrared (FTIR), ultraviolet-visible (UV-Vis) and proton nuclear magnetic resonance (¹H NMR) spectroscopy, conductometry and single-crystal X-ray diffraction. The cytotoxicity of these complexes was evaluated in the HepG2, HeLa, MDA-MB-231, K-562, DU 145 and MRC-5 cancer cell lines. The strongest antiproliferative results were observed in MDA-MB-231 and HepG2 cells, in which these complexes displayed significant selective toxicity (3.1 and 3.6, respectively) compared with their effects on normal MRC-5 cells. In vivo studies were performed using an alternative model (Artemia salina L.) to assure the safety of these complexes, and the results were confirmed using a conventional model (BALB/c mice). Finally, tests of oral bioavailability showed maximum plasma concentrations of 3029.50 µg/L and 1191.95 µg/L for complexes 1 and 2, respectively. According to all obtained results, both compounds could be considered as prospective antiproliferative agents that warrant further research.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacocinética , Tiosemicarbazonas/síntesis química , Tiosemicarbazonas/farmacocinética , Zinc/química , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Artemia , Disponibilidad Biológica , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Células HeLa , Células Hep G2 , Humanos , Técnicas In Vitro , Ratones , Estructura Molecular , Tiosemicarbazonas/administración & dosificación , Tiosemicarbazonas/química , Pruebas de Toxicidad Aguda
7.
Int J Mol Sci ; 17(5)2016 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-27196901

RESUMEN

Tuberculosis (TB) is an infectious disease caused mainly by the bacillus Mycobacterium tuberculosis (Mtb), presenting 9.5 million new cases and 1.5 million deaths in 2014. The aim of this study was to evaluate a nanostructured lipid system (NLS) composed of 10% phase oil (cholesterol), 10% surfactant (soy phosphatidylcholine, sodium oleate), and Eumulgin(®) HRE 40 ([castor oil polyoxyl-40-hydrogenated] in a proportion of 3:6:8), and an 80% aqueous phase (phosphate buffer pH = 7.4) as a tactic to enhance the in vitro anti-Mtb activity of the copper(II) complexes [CuCl2(INH)2]·H2O (1), [Cu(NCS)2(INH)2]·5H2O (2) and [Cu(NCO)2(INH)2]·4H2O (3). The Cu(II) complex-loaded NLS displayed sizes ranging from 169.5 ± 0.7095 to 211.1 ± 0.8963 nm, polydispersity index (PDI) varying from 0.135 ± 0.0130 to 0.236 ± 0.00100, and zeta potential ranging from -0.00690 ± 0.0896 to -8.43 ± 1.63 mV. Rheological analysis showed that the formulations behave as non-Newtonian fluids of the pseudoplastic and viscoelastic type. Antimycobacterial activities of the free complexes and NLS-loaded complexes against Mtb H37Rv ATCC 27294 were evaluated by the REMA methodology, and the selectivity index (SI) was calculated using the cytotoxicity index (IC50) against Vero (ATCC(®) CCL-81), J774A.1 (ATCC(®) TIB-67), and MRC-5 (ATCC(®) CCL-171) cell lines. The data suggest that the incorporation of the complexes into NLS improved the inhibitory action against Mtb by 52-, 27-, and 4.7-fold and the SI values by 173-, 43-, and 7-fold for the compounds 1, 2 and 3, respectively. The incorporation of the complexes 1, 2 and 3 into the NLS also resulted in a significant decrease of toxicity towards an alternative model (Artemia salina L.). These findings suggest that the NLS may be considered as a platform for incorporation of metallic complexes aimed at the treatment of TB.


Asunto(s)
Antituberculosos/farmacología , Complejos de Coordinación/farmacología , Cobre/química , Mycobacterium tuberculosis/efectos de los fármacos , Animales , Antituberculosos/química , Línea Celular , Chlorocebus aethiops , Complejos de Coordinación/química , Humanos , Lípidos/química , Ratones , Pruebas de Sensibilidad Microbiana/métodos , Nanoestructuras/química , Tamaño de la Partícula , Tuberculosis , Células Vero
8.
Cancer Sci ; 106(9): 1188-95, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26250335

RESUMEN

In medulloblastoma, abnormal expression of pluripotency factors such as LIN28 and OCT4 has been correlated with poor patient survival. The miR-302/367 cluster has also been shown to control self-renewal and pluripotency in human embryonic stem cells and induced pluripotent stem cells, but there is limited, mostly correlational, information about these pluripotency-related miRNA in cancer. We evaluated whether aberrant expression of such miRNA could affect tumor cell behavior and stem-like traits, thereby contributing to the aggressiveness of medulloblastoma cells. Basal expression of primary and mature forms of miR-367 were detected in four human medulloblastoma cell lines and expression of the latter was found to be upregulated upon enforced expression of OCT4A. Transient overexpression of miR-367 significantly enhanced tumor features typically correlated with poor prognosis; namely, cell proliferation, 3-D tumor spheroid cell invasion and the ability to generate neurosphere-like structures enriched in CD133 expressing cells. A concurrent downregulation of the miR-367 cancer-related targets RYR3, ITGAV and RAB23, was also detected in miR-367-overexpressing cells. Overall, these findings support the pro-oncogenic activity of miR-367 in medulloblastoma and reveal a possible mechanism contributing to tumor aggressiveness, which could be further explored to improve patient stratification and treatment of this important type of pediatric brain cancer.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Proliferación Celular/genética , Meduloblastoma/genética , Meduloblastoma/patología , MicroARNs/genética , Antígeno AC133 , Antígenos CD/genética , Línea Celular Tumoral , Regulación hacia Abajo/genética , Glicoproteínas/genética , Humanos , Factor 3 de Transcripción de Unión a Octámeros/genética , Péptidos/genética , Canal Liberador de Calcio Receptor de Rianodina/genética , Esferoides Celulares/patología , Regulación hacia Arriba/genética , Proteínas de Unión al GTP rab/genética
9.
Molecules ; 20(12): 22534-45, 2015 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-26694337

RESUMEN

The aim of this study was to construct a nanostructured lipid system as a strategy to improve the in vitro antibacterial activity of copper(II) complexes. New compounds with the general formulae [CuX2(INH)2]·nH2O (X = Cl(-) and n = 1 (1); X = NCS(-) and n = 5 (2); X = NCO(-) and n = 4 (3); INH = isoniazid, a drug widely used to treat tuberculosis) derived from the reaction between the copper(II) chloride and isoniazid in the presence or absence of pseudohalide ions (NCS(-) or NCO(-)) were synthesized and characterized by infrared spectrometry, electronic absorption spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, elemental analysis, melting points and complexometry with 2,2',2'',2'''-(Ethane-1,2-diyldinitrilo)tetraacetic acid (EDTA). The characterization techniques allowed us to confirm the formation of the copper(II) complexes. The Cu(II) complexes were loaded into microemulsion (MEs) composed of 10% phase oil (cholesterol), 10% surfactant [soy oleate and Brij(®) 58 (1:2)] and 80% aqueous phase (phosphate buffer pH = 7.4) prepared by sonication. The Cu(II) complex-loaded MEs displayed sizes ranging from 158.0 ± 1.060 to 212.6 ± 1.539 nm, whereas the polydispersity index (PDI) ranged from 0.218 ± 0.007 to 0.284 ± 0.034. The antibacterial activity of the free compounds and those that were loaded into the MEs against Staphylococcus aureus ATCC(®) 25923 and Escherichia coli ATCC(®) 25922, as evaluated by a microdilution technique, and the cytotoxicity index (IC50) against the Vero cell line (ATCC(®) CCL-81(TM)) were used to calculate the selectivity index (SI). Among the free compounds, only compound 2 (MIC 500 µg/mL) showed activity for S. aureus. After loading the compounds into the MEs, the antibacterial activity of compounds 1, 2 and 3 was significantly increased against E. coli (MIC's 125, 125 and 500 µg/mL, respectively) and S. aureus (MICs 250, 500 and 125 µg/mL, respectively). The loaded compounds were less toxic against the Vero cell line, especially compound 1 (IC50 from 109.5 to 319.3 µg/mL). The compound 2- and 3-loaded MEs displayed the best SI for E. coli and S. aureus, respectively. These results indicated that the Cu(II) complex-loaded MEs were considerably more selective than the free compounds, in some cases, up to 40 times higher.


Asunto(s)
Antibacterianos/química , Complejos de Coordinación/química , Cobre/química , Nanoestructuras/química , Antibacterianos/farmacología , Complejos de Coordinación/farmacología , Cobre/farmacología , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Staphylococcus aureus/efectos de los fármacos
10.
Int Immunopharmacol ; 130: 111701, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38382266

RESUMEN

Pregnant women with preeclampsia (PE) present a shift in the immune response to an inflammatory profile. This deviation could be due to the interaction of tumor necrosis factor (TNF) with TNFR1 and TNFR2 receptors, besides the failure in modulation of inflammation regulatory mechanisms. This study evaluated the effects of progesterone on the expression of TNFR1 and TNFR2 by Jurkat cells after stimulation with plasma from PE and normotensive (NT) pregnant women. Jurkat cells were cultured with or without progesterone in a medium containing 20% (v/v) plasma from PE or NT women. The expression of TNF receptors was evaluated by flow cytometry. The concentration of soluble forms of TNF receptors and cytokines was determined in culture supernatant and plasma by ELISA. The plasma of PE women showed significantly higher concentrations of sTNFR1 and TNF and lower concentrations of sTNFR2 compared to the NT group. TNFR1 receptor expression was increased in Jurkat cells, while TNFR2 was decreased after culture with PE plasma when compared with Jurkat cells cultured with progesterone and plasma from NT women. The concentration of sTNFR1, TNF, and IL-10 in the culture supernatant of Jurkat cells was increased after culture with PE plasma, while the sTNFR2 receptor was decreased when compared to the NT group. Results demonstrate that in preeclamptic women a systemic inflammation occurs with an increase of inflammatory molecules, and progesterone may have a modulating effect on the expression of TNF receptors, shifting Jurkat cells towards an anti-inflammatory profile with greater expression of TNFR2.


Asunto(s)
Preeclampsia , Progesterona , Receptores Tipo II del Factor de Necrosis Tumoral , Receptores Tipo I de Factores de Necrosis Tumoral , Femenino , Humanos , Embarazo , Células Cultivadas , Inflamación/metabolismo , Células Jurkat , Preeclampsia/metabolismo , Mujeres Embarazadas , Progesterona/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Receptores Tipo II del Factor de Necrosis Tumoral/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
11.
Pregnancy Hypertens ; 29: 46-53, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35728369

RESUMEN

OBJECTIVE: This study compared the modulatory effect of two intravenous magnesium sulfate (MgSO4) regimens on the systemic inflammatory response in pregnant women diagnosed with imminent eclampsia. STUDY DESIGN: In a single-blind cross-sectional study, 33 women were allocated according to the Zuspan (n = 16) and Sibai (n = 17) MgSO4 regimens, and treated for 24 h. Blood samples were collected pre-administration of the loading dose, at 24 h of the maintenance dose of MgSO4, and at 48 h, when patients were without treatment. Plasma was used to determine interleukin (IL)-1 beta (IL-1ß), IL-6, IL-10, tumor necrosis factor-alpha (TNF-α), heat shock protein (Hsp70), and heme oxygenase-1 (HO-1) by ELISA. RESULTS: The treatment with the Zuspan's regimen didn't change plasma concentrations of TNF-α, IL-10, and Hsp70 in the three-time points studied. However, it decreased IL-1ß at 24 h and 48 h and IL-6 at 48 h, and increased HO-1 concentration at 48 h. On the other hand, compared to the pre-treatment period, Sibai's regimen induced a significant decrease in TNF-α, IL-1ß, IL-6, and Hsp70, while increased HO-1 levels both at 24 h and 48 h and, IL-10 concentration at 48 h. CONCLUSIONS: Sibai's regimen determined an early and efficient immunoregulatory effect on systemic inflammatory response in preeclampsia, suggesting that the maintenance dose of two grams of MgSO4 was better than one gram in the treatment of imminent eclampsia.


Asunto(s)
Eclampsia , Sulfato de Magnesio , Síndrome de Respuesta Inflamatoria Sistémica , Estudios Transversales , Eclampsia/tratamiento farmacológico , Femenino , Humanos , Interleucina-10 , Interleucina-6 , Sulfato de Magnesio/uso terapéutico , Preeclampsia/tratamiento farmacológico , Embarazo , Mujeres Embarazadas , Método Simple Ciego , Síndrome de Respuesta Inflamatoria Sistémica/tratamiento farmacológico , Factor de Necrosis Tumoral alfa
12.
Future Microbiol ; 17: 281-291, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35152707

RESUMEN

Aim: Octyl gallate (OG) loaded into a nanostructured lipid system (NLS) was tested for antifungal activity and in vitro and in vivo toxicity. Methods & Results: The features of NLS-OG were analyzed by dynamic light scattering and showed adequate size (132.1 nm) and homogeneity (polydispersity index = 0.200). OG was active against Paraccoccidioides spp., and NLS-OG did not affect antifungal activity. NLS-OG demonstrated reduced toxicity to lung cells and zebrafish embryos compared with OG, whereas NLS was toxic to hepatic cells. OG and NLS-OG did not show toxicity in a Galleria mellonella model at 20 mg/kg. All toxic concentrations were superior to MIC (antifungal activity). Conclusion: These results indicate good anti-Paracoccidioides activity and low toxicity of NLS-OG.


Plain language summary Drugs for the treatment of fungal diseases are limited in number and present side effects, drug interactions, risks for pregnant women and fungal resistance. The authors produced a derivative compound from plants called octyl gallate (OG) and then incorporated it into a nanoparticle lipid system (NLS) for better distribution in biological fluids. NLS-OG was tested against a fungus called Paracoccidioides, which causes lung infections. The toxicity profile of NLS-OG was also evaluated in lung and hepatic cells as well as novel animal models. NLS-OG presented good antifungal activity and low toxicity in lung cells and embryos.


Asunto(s)
Antifúngicos , Paracoccidioides , Animales , Antifúngicos/toxicidad , Ácido Gálico/análogos & derivados , Lípidos , Pez Cebra
13.
PLoS One ; 16(3): e0246811, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33661933

RESUMEN

The treatment of Chagas disease (CD), a neglected parasitic condition caused by Trypanosoma cruzi, is still based on only two drugs, nifurtimox (Nif) and benznidazole (Bz), both of which have limited efficacy in the late chronic phase and induce severe side effects. This scenario justifies the continuous search for alternative drugs, and in this context, the natural naphthoquinone ß-lapachone (ß-Lap) and its derivatives have demonstrated important trypanocidal activities. Unfortunately, the decrease in trypanocidal activity in the blood, high toxicity to mammalian cells and low water solubility of ß-Lap limit its systemic administration and, consequently, clinical applications. For this reason, carriers as drug delivery systems can strategically maximize the therapeutic effects of this drug, overcoming the above mentioned restrictions. Accordingly, the aim of this study is to investigate the in vitro anti-T. cruzi effects of ß-Lap encapsulated in2-hydroxypropyl-ß-cyclodextrin (2HP-ß-CD) and its potential toxicity to mammalian cells.


Asunto(s)
Portadores de Fármacos/química , Naftoquinonas/química , Naftoquinonas/farmacología , Tripanocidas/química , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Línea Celular , Solubilidad
14.
J Antimicrob Chemother ; 64(4): 747-50, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19671588

RESUMEN

OBJECTIVES: Aromatic diamidines (ADs) have been recognized as promising antiparasitic agents. Therefore, in the present work, the in vitro trypanocidal effect of 11 ADs upon the relevant clinical forms of Trypanosoma cruzi was evaluated, as well as determining their toxicity to mammalian cells and their subcellular localization. METHODS: The trypanocidal effect upon trypomastigotes and amastigotes was evaluated by light microscopy through the determination of the IC(50) values. The cytotoxicity was determined by the MTT colorimetric assay against mouse cardiomyocytes. For the subcellular localization, transmission electron microscopy and fluorescence approaches were used. The fluorescence intensity within the kinetoplast DNA (kDNA) and nuclear DNA (nDNA) of treated parasites was determined using the Image J program. RESULTS: Compounds 2, 5 and 7 showed the lowest IC(50) values (micromolar range) against intracellular amastigotes and trypomastigotes. In the presence of blood, all the tested ADs exhibited a reduction of their activity. The compounds did not exhibit toxicity to cardiac cells and the highest selectivity index (SI) was achieved by compound 5 with an SI of >137 for trypomastigotes and compound 7 with an SI of >107 for intracellular parasites. The subcellular effects upon bloodstream forms treated with compounds 5 and 7 were mainly on kDNA, leading to its disorganization. The higher accumulation in the kDNA observed for all tested ADs was not directly related to their efficacy. CONCLUSIONS: Our results show the high activity of this new series of ADs against both trypomastigote and amastigote forms, with excellent SIs, especially compound 7, which merits further in vivo evaluation.


Asunto(s)
Antiprotozoarios/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Antiprotozoarios/toxicidad , Supervivencia Celular , Células Cultivadas , Concentración 50 Inhibidora , Ratones , Microscopía Electrónica de Transmisión , Miocitos Cardíacos/efectos de los fármacos , Sales de Tetrazolio/metabolismo , Tiazoles/metabolismo , Trypanosoma cruzi/ultraestructura
15.
Front Microbiol ; 10: 1667, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31417503

RESUMEN

Currently 75-88% of fungal infections are caused by Candida species, and Candida albicans is the main microorganism that causes these infections, especially oral candidiasis. An option for treatment involves the use of the antifungal peptide Histatin 5 (Hst 5), which is naturally found in human saliva but undergoes rapid degradation when present in the oral cavity, its site of action. For this reason, it is important to develop a way of applying this peptide to the oral lesions, which promotes the gradual release of the peptide. In the present study, we have evaluated the development of liposomes of different lipid compositions, loaded with the peptide as a way to promote its release slowly and gradually, preserving its antifungal potential. For this, the peptide 0WHistatin 5, an analog of the peptide Hst 5, was synthesized, which contains the amino acid tryptophan in its sequence. The solid phase synthesis method was used, followed by cleavage and purification. The liposomes were produced by thin film hydration technique in three different lipid compositions, F1, F2, and F3 and were submitted to an extrusion and sonication process to standardize the size and study the best technique for their production. The liposomes were characterized by dynamic light scattering, and tests were performed to determine the encapsulation efficiency, release kinetics, stability, and evaluation of antifungal activity. The extruded liposomes presented average size in the range of 100 nm, while sonicated liposomes presented a smaller size in the range of 80 nm. The encapsulation efficiency was higher for the sonicated liposomes, being 34.5% for F1. The sonicated F3 presented better stability when stored for 60 days at 4°C. The liposomes showed the ability to release the peptide for the total time of 96 h, with the first peak after 5 h, and a further increase of the released after 30 h. Time-kill assay showed that the liposomes were able to control yeast growth for 72 h. The data suggest that the liposomes loaded with 0WHistatin 5 maintained the action of the peptide and were able to limit the growth of C. albicans, being a suitable system for use in the treatment of oral candidiasis.

18.
Nat Commun ; 10(1): 3914, 2019 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-31477715

RESUMEN

YAP1 fusion-positive supratentorial ependymomas predominantly occur in infants, but the molecular mechanisms of oncogenesis are unknown. Here we show YAP1-MAMLD1 fusions are sufficient to drive malignant transformation in mice, and the resulting tumors share histo-molecular characteristics of human ependymomas. Nuclear localization of YAP1-MAMLD1 protein is mediated by MAMLD1 and independent of YAP1-Ser127 phosphorylation. Chromatin immunoprecipitation-sequencing analyses of human YAP1-MAMLD1-positive ependymoma reveal enrichment of NFI and TEAD transcription factor binding site motifs in YAP1-bound regulatory elements, suggesting a role for these transcription factors in YAP1-MAMLD1-driven tumorigenesis. Mutation of the TEAD binding site in the YAP1 fusion or repression of NFI targets prevents tumor induction in mice. Together, these results demonstrate that the YAP1-MAMLD1 fusion functions as an oncogenic driver of ependymoma through recruitment of TEADs and NFIs, indicating a rationale for preclinical studies to block the interaction between YAP1 fusions and NFI and TEAD transcription factors.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Neoplasias Encefálicas/metabolismo , Carcinogénesis/metabolismo , Proteínas de Unión al ADN/metabolismo , Ependimoma/metabolismo , Factores de Transcripción NFI/metabolismo , Proteínas Nucleares/metabolismo , Factores de Transcripción/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Carcinogénesis/genética , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Proteínas de Unión al ADN/genética , Ependimoma/genética , Ependimoma/patología , Células HEK293 , Humanos , Ratones , Factores de Transcripción NFI/genética , Células 3T3 NIH , Células-Madre Neurales/metabolismo , Células-Madre Neurales/patología , Proteínas Nucleares/genética , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Factores de Transcripción/genética , Proteínas Señalizadoras YAP
19.
Front Microbiol ; 9: 2930, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30574128

RESUMEN

Tuberculosis (TB) is an infectious, airborne disease caused by the bacterium Mycobacterium tuberculosis that mainly affects the lungs. Fortunately, tuberculosis is a curable disease, and in recent years, death rates for this disease have decreased. However, the existence of antibiotic-resistant strains and the occurrence of co-infections with human immunodeficiency virus (HIV), have led to increased mortality in recent years. Another area of concern is that one-third of the world's population is currently infected with M. tuberculosis in its latent state, serving as a potential reservoir for active TB. In an effort to address the failure of current TB drugs, greater attention is being given to the importance of bioinorganic chemistry as an ally in new research into the development of anti-TB drugs. Ruthenium (Ru) is a chemical element that can mimic iron (Fe) in the body. In previous studies involving the following heteroleptic Ru complexes, [Ru(pic)(dppb)(bipy)]PF6 (SCAR1), [Ru(pic)(dppb)(Me-bipy)]PF6 (SCAR2), [Ru(pic)(dppb)(phen)]PF6 (SCAR4), cis-[Ru(pic)(dppe)2]PF6 (SCAR5), and [Ru(pic)(dppe)(phen)]PF6 (SCAR7), we observed excellent anti-TB activity, moderate cell-toxicity, and a lack of oral bioavailability in an in vivo model of these complexes. Therefore, the objective of this study was to evaluate the toxicity and oral bioavailability of these complexes by loading them into a nanostructured lipid system. The nanostructured lipid system was generated using different ratios of surfactant (soybean phosphatidylcholine, Eumulgin®, and sodium oleate), aqueous phase (phosphate buffer with a concentration of 1X and pH 7.4), and oil (cholesterol) to generate a system for the incorporation of Ru(II) compounds. The anti-TB activity of the compounds was determined using a microdilution assay with Resazurin (REMA) against strains of M. tuberculosis H37Rv and clinical isolates resistant. Cytotoxicity assay using J774.A1 cells (ATCC TIB-67) and intra-macrophage activity were performed. The oral bioavailability assay was used to analyze blood collected from female BALB/C mice. Plasma collected from the same mice was analyzed via inductively coupled plasma mass spectrometry (ICP-MS) to quantify the number of Ru ions. The complexes loaded into the nanostructured lipid system maintained in vitro activity and toxicity was found to be reduced compared with the compounds that were not loaded. The complexes showed intra-macrophagic activity and were orally bioavailable.

20.
Stem Cells Int ; 2017: 4972078, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28553358

RESUMEN

Pericytes are important cellular components of the tumor microenviroment with established roles in angiogenesis and metastasis. These two cancer hallmarks are modulated by enzymes of the LOX family, but thus far, information about LOX relevance in tumor-associated pericytes is lacking. Here, we performed a comparative characterization of normal and tumoral pericytes and report for the first time the modulatory effects of LOX enzymes on activated pericyte properties. Tumoral pericytes isolated from childhood ependymoma and neuroblastoma specimens displayed angiogenic properties in vitro and expressed typical markers, including CD146, NG2, and PDGFRß. Expression of all LOX family members could be detected in both normal and tumor-associated pericytes. In most pericyte samples, LOXL3 was the family member displaying the highest transcript levels. Inhibition of LOX/LOXL activity with the inhibitor ß-aminopropionitrile (ßAPN) significantly reduced migration of pericytes, while proliferation rates were kept unaltered. Formation of tube-like structures in vitro by pericytes was also significantly impaired upon inhibition of LOX/LOXL activity with ßAPN, which induced more prominent effects in tumor-associated pericytes. These findings reveal a novel involvement of the LOX family of enzymes in migration and angiogenic properties of pericytes, with implications in tumor development and in therapeutic targeting tumor microenvironment constituents.

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