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1.
AAPS PharmSciTech ; 23(7): 255, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36109444

RESUMEN

Doxorubicin (DOX) is a chemotherapeutic agent that has been used in the treatment of breast cancer. However, serious toxic effects have limited its use, mainly cardiotoxicity. To minimize the adverse effects, liposomal preparations containing DOX have been developed. These preparations can reach the target in the tumor region as well as bypass the resistance-related problems. An alternative to increased therapeutic efficacy may be the fusion of liposomes with exosomes released from tumor cells to facilitate membrane and fusion interactions, achieving greater cell uptake. Thus, the purpose of this study was the fusion of exosomes derived from breast tumor cells with long-circulating and pH-sensitive liposomes loading DOX (ExoSpHL-DOX) for the treatment of breast cancer. The mean diameter of ExoSpHL-DOX was 100.8 ± 7.8 nm, the polydispersity index was 0.122 ± 0.004, and the encapsulated DOX content was equal to 83.5 ± 2.5%. The fusion of exosomes with long-circulating and pH-sensitive liposomes was confirmed by Fourier transform infrared spectroscopy, Raman spectroscopy, and nano-flow cytometry. The physicochemical characteristics of ExoSpHL-DOX were maintained for 60 days, at 4 °C. The study of the release of DOX from ExoSpHL-DOX in dilution media with different pH values showed the pH sensitivity characteristic of the nanosystem, since 96.6 ± 0.2% of DOX was released from ExoSpHL-DOX at pH 5.0, while at pH 7.4, the release was 70.1 ± 1.7% in the medium. The cytotoxic study against the breast cancer cell line demonstrated that ExoSpHL-DOX treatment significantly reduced the cancer cell viability.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Exosomas , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Doxorrubicina/química , Doxorrubicina/farmacología , Exosomas/patología , Femenino , Humanos , Concentración de Iones de Hidrógeno , Liposomas/química
2.
Braz J Biol ; 82: e256261, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35894349

RESUMEN

Interest in antiviral plant species has grown exponentially and some have been reported to have anti-HIV properties. This research aims to perform the bio-guided phytochemical fractionation by antiretroviral activity of Lafoensia pacari stem barks. This in vitro experimental study involved the preparation of plant material, obtention of ethanolic extract, fractionation, purification, identification and quantification of fractions, acid-base extraction, nuclear magnetic resonance, HIV-1 RT inhibition test and molecular docking studies. From the bio-guided fractionation by the antiretroviral activity there was a higher activity in the acetanolic subfractions, highlighting the acetate subfraction - neutrals with 60.98% of RT inhibition and ellagic acid with 88.61% of RT inhibition and absence of cytotoxicity. The macrophage lineage cytotoxicity assay showed that the chloroform fraction was more toxic than the acetate fraction. The analysis of the J-resolved spectrum in the aromatic region showed a singlet at 7.48 and 6.93 ppm which was identified as ellagic acid and gallic acid, respectively. The 5TIQ enzyme obtained better affinity parameter with the ellagic acid ligand, which was confirmed by the HSQC-1H-13C spectra. Gallic acid was also favorable to form interaction with the 5TIQ enzyme, being confirmed through the HSQC-1H-13C spectrum. From the PreADMET evaluation it was found that ellagic acid is a promising molecule for its RT inhibition activity and pharmacokinetic and toxicity parameters.


Asunto(s)
Infecciones por VIH , Lythraceae , Acetatos , Ácido Elágico/farmacología , Ácido Gálico/farmacología , Lythraceae/química , Simulación del Acoplamiento Molecular , Extractos Vegetales/toxicidad
3.
Cancers (Basel) ; 14(9)2022 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-35565241

RESUMEN

Patients with clear cell renal cell carcinoma (ccRCC) have poor survival outcomes, especially if it has metastasized. It is of paramount importance to identify biomarkers in genomic data that could help predict the aggressiveness of ccRCC and its resistance to drugs. Thus, we conducted a study with the aims of evaluating gene signatures and proposing a novel one with higher predictive power and generalization in comparison to the former signatures. Using ccRCC cohorts of the Cancer Genome Atlas (TCGA-KIRC) and International Cancer Genome Consortium (ICGC-RECA), we evaluated linear survival models of Cox regression with 14 signatures and six methods of feature selection, and performed functional analysis and differential gene expression approaches. In this study, we established a 13-gene signature (AR, AL353637.1, DPP6, FOXJ1, GNB3, HHLA2, IL4, LIMCH1, LINC01732, OTX1, SAA1, SEMA3G, ZIC2) whose expression levels are able to predict distinct outcomes of patients with ccRCC. Moreover, we performed a comparison between our signature and others from the literature. The best-performing gene signature was achieved using the ensemble method Min-Redundancy and Max-Relevance (mRMR). This signature comprises unique features in comparison to the others, such as generalization through different cohorts and being functionally enriched in significant pathways: Urothelial Carcinoma, Chronic Kidney disease, and Transitional cell carcinoma, Nephrolithiasis. From the 13 genes in our signature, eight are known to be correlated with ccRCC patient survival and four are immune-related. Our model showed a performance of 0.82 using the Receiver Operator Characteristic (ROC) Area Under Curve (AUC) metric and it generalized well between the cohorts. Our findings revealed two clusters of genes with high expression (SAA1, OTX1, ZIC2, LINC01732, GNB3 and IL4) and low expression (AL353637.1, AR, HHLA2, LIMCH1, SEMA3G, DPP6, and FOXJ1) which are both correlated with poor prognosis. This signature can potentially be used in clinical practice to support patient treatment care and follow-up.

4.
Braz. j. biol ; 82: e256261, 2022. tab, graf, ilus
Artículo en Inglés | VETINDEX | ID: biblio-1384051

RESUMEN

Interest in antiviral plant species has grown exponentially and some have been reported to have anti-HIV properties. This research aims to perform the bio-guided phytochemical fractionation by antiretroviral activity of Lafoensia pacari stem barks. This in vitro experimental study involved the preparation of plant material, obtention of ethanolic extract, fractionation, purification, identification and quantification of fractions, acid-base extraction, nuclear magnetic resonance, HIV-1 RT inhibition test and molecular docking studies. From the bio-guided fractionation by the antiretroviral activity there was a higher activity in the acetanolic subfractions, highlighting the acetate subfraction - neutrals with 60.98% of RT inhibition and ellagic acid with 88.61% of RT inhibition and absence of cytotoxicity. The macrophage lineage cytotoxicity assay showed that the chloroform fraction was more toxic than the acetate fraction. The analysis of the J-resolved spectrum in the aromatic region showed a singlet at 7.48 and 6.93 ppm which was identified as ellagic acid and gallic acid, respectively. The 5TIQ enzyme obtained better affinity parameter with the ellagic acid ligand, which was confirmed by the HSQC-1H-13C spectra. Gallic acid was also favorable to form interaction with the 5TIQ enzyme, being confirmed through the HSQC-1H-13C spectrum. From the PreADMET evaluation it was found that ellagic acid is a promising molecule for its RT inhibition activity and pharmacokinetic and toxicity parameters.


O interesse por espécies vegetais com ação antiviral tem crescido exponencialmente e algumas tem sido relatadas como possuídoras de propriedades anti-HIV. Essa pesquisa tem como objetivo realizar o fracionamento fitoquímico biodirecionado pela atividade antirretroviral das cascas do caule da espécie Lafoensia pacari. Trata-se de um estudo experimental in vitro e a metodologia envolve preparo do material vegetal, obtenção do extrato etanólico, fracionamento, purificação, identificação e quantificação das frações, extração ácido-base, ressonância magnética nuclear, teste de inibição da TR do HIV-1 e estudos de docking molecular. A partir do fracionamento biodirecionado pela atividade antirretroviral verificou-se uma maior atividade nas subfrações acetanólica. Com destaque para a subfração acetanólica neutros com 60,98% de inibição de TR e o ácido elágico com 88,61% de inibição de TR e ausência de citotoxicidade. Verificou-se com o teste de citotoxicidade em linhagem de macrófagos que a fração clorofórmica foi mais tóxica que a fração acetanólica. A análise do espectro J-resolvido na região aromática apresentou um simpleto em 7.48 e 6.93 ppm que foram identificados como ácido elágico e ácido gálico respectivamente. A enzima 5TIQ obteve melhor parâmetro de afinidade com o ligante ácido elágico que foi confirmado pelos espectros HSQC-1H-13C. O ácido gálico mostrou-se também favorável a formar interação com a enzima 5TIQ, sendo confirmado através do espectro HSQC-1H-13C. Através da avaliação do PreADMET verificou-se que o ácido elágico é uma molécula promissora pela sua atividade de inibição da TR e parâmetros farmacocinéticos e de toxicidade.


Asunto(s)
VIH , Antirretrovirales , Simulación del Acoplamiento Molecular , Macrófagos , Fitoterapia
5.
Appl Biochem Biotechnol ; 184(4): 1375-1389, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29043662

RESUMEN

We evaluated the chemical composition, antioxidant activity, and antitumor potential of a fraction that was isolated from Stryphnodendron adstringens (barbatimão) leaf aqueous extract. Fraction is composed by gallic acid, procyanidin dimer B1, and (-)-epicatechin-3-O-gallate and it exhibits antioxidant and cytotoxic activities. Fraction was cytotoxic against two human breast cancer cell lines, ER (+) and MCF-7 and the triple-negative, MDA-MB-435. The sulforhodamine B assay showed that, as compared to normal control cells, the fraction significantly (P < 0.05) decreased cancer cell viability. The morphological alterations noted in the treated cancer cells were cell rounding-up, shrinkage, and nuclear condensation reduction of cell diameter and length. Treatment with fraction increased cancer cell expression of Bax, caspase-9, active caspase-3, caspase-8, LC-3, and beclin-1 and decreased Bcl-2, caspase-3, and pro-caspase-8 expression. Altogether, fraction is cytotoxic to both breast cancer cell lines, induces cell death, and its mechanism of action seems to include the induction of apoptosis. Our data support a positive role of the fraction as a chemopreventive agent for antineoplastic drug development.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Citotoxinas/farmacología , Fabaceae/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Antineoplásicos Fitogénicos/química , Antioxidantes/química , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Citotoxinas/química , Femenino , Humanos , Células MCF-7 , Proteínas de Neoplasias/metabolismo , Extractos Vegetales/química
6.
Clin Transl Oncol ; 18(12): 1243-1253, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27896639

RESUMEN

Bone metastases are common in many advanced solid tumours, being breast, prostate, thyroid, lung, and renal cancer the most prevalent. Bone metastases can produce skeletal-related events (SREs), defined as pathological fracture, spinal cord compression, need of bone irradiation or need of bone surgery, and hypercalcaemia. Patients with bone metastases experience pain, functional impairment and have a negative impact on their quality of life. Several imaging techniques are available for diagnosis of this disease. Bone-targeted therapies include zoledronic acid, a potent biphosfonate, and denosumab, an anti-RANKL monoclonal antibody. Both reduce the risk and/or delay the development of SREs in several types of tumours. Radium 233, an alpha-particle emitter, increases overall survival in patients with bone metastases from resistant castration prostate cancer. Multidisciplinary approach is essential and bone surgery and radiotherapy should be integrated in the treatment of bone metastases when necessary. This SEOM Guideline reviews bone metastases pathogenesis, clinical presentations, lab tests, imaging techniques for diagnosis and response assessment, bone-targeted agents, and local therapies, as radiation and surgery, and establishes recommendations for the management of patients with metastases to bone.


Asunto(s)
Neoplasias Óseas , Neoplasias/patología , Guías de Práctica Clínica como Asunto , Neoplasias Óseas/diagnóstico , Neoplasias Óseas/secundario , Neoplasias Óseas/terapia , Humanos , España
7.
Genet Mol Res ; 14(3): 9585-94, 2015 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-26345891

RESUMEN

Recent studies have shown an association between thrombosis and factor VII (FVII), tissue factor (TF), and angiotensin-converting enzyme (ACE). This suggests that individuals with FVII-402 G/A, FVII-401 G/T, TF+5466 A/G, and ACE-287 insertion/deletion (I/D) polymorphisms present an increased risk of venous thrombosis, heart disease, and ischemic stroke compared with controls. In this study, we investigated the frequencies of these polymorphisms and their association with arterial and venous thrombosis. For the FVII-402 G/A polymorphism, there were 57.3% heterozygote (HT) genotypes and 8.3% homozygote (HM) genotypes in the patients, and 45.2% HT genotypes and 15.4% HM genotypes in the controls. For the FVII-401 G/T polymorphism, there were 37.5% HT genotypes and 3.1% HM genotypes in the patients, and 32.7% HT genotypes and 4.8% HM genotypes in the controls. The polymorphism TF+5466 A/G was not found in any of the samples analyzed. For the ACE-287 I/D polymorphism, there were 43 (40.6%) HT genotypes and 63 (59.4%) HM genotypes in the controls and 28 (45.2%) HT genotypes and 34 (54.8%) HM genotypes in the patients. No significant difference was observed by comparing patients and controls. In this study, no association was found between the presence of the evaluated polymorphisms and the occurrence of thrombotic events.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Trombosis/genética , Adolescente , Adulto , Alelos , Estudios de Casos y Controles , Niño , Factor VII/genética , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Peptidil-Dipeptidasa A/genética , Polimorfismo Genético , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Tromboplastina/genética , Trombosis/etiología , Trombosis de la Vena/genética , Adulto Joven
8.
Mol Biol Rep ; 38(7): 4381-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21132386

RESUMEN

Apolipoprotein A5 (APOA5) and apolipoprotein E (APOE) play important roles in the metabolism of cholesterol and triglycerides. The aim of this study was to determine the allelic and genotypic distributions of the APOA5-1131T>C (rs 662799) and the APOE HhaI polymorphisms and to identify the association of both individual and combined APOA5-APOE genetic variants and the risk for dyslipidemia in children and adolescents. We genotyped 53 dyslipidemic and 77 normolipidemic individuals. The total cholesterol, triglycerides and HDL cholesterol were determined enzymatically. For APOA5 polymorphism, the presence of the allele C confers an individual risk for dyslipidemia (OR = 2.38, 95% CI = 1.15-4.89; P = 0.018). No significant differences were observed for lipid parameters among the APOA5 groups, except for a higher value of HDLc (P = 0.024) in C-carriers. The allelic and genotypic frequencies of APOE polymorphism were similar between groups and did not increase the susceptibility for dyslipidemia. None of the combined APOA5-APOE polymorphisms increased risk for dyslipidemia. We demonstrated an association between APOA5-1131T>C polymorphism and dyslipidemia in children and adolescents. This finding may be useful to guide new studies with genetic markers down a path toward a better characterization of the genetic risk factors for dyslipidemia and atherosclerotic diseases.


Asunto(s)
Apolipoproteínas A/genética , Apolipoproteínas E/genética , Dislipidemias/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Adolescente , Apolipoproteína A-V , Niño , Demografía , Dislipidemias/sangre , Femenino , Frecuencia de los Genes/genética , Humanos , Lípidos/sangre , Masculino , Adulto Joven
9.
J Antimicrob Chemother ; 63(2): 337-9, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19038979

RESUMEN

OBJECTIVES: The antifungal activity of curcumin was evaluated against 23 fungi strains and its in vitro inhibitory effect on the adhesion of Candida species to human buccal epithelial cells (BEC) was also investigated. METHODS: The antifungal susceptibility was evaluated by broth microdilution assay following the CLSI (formerly the NCCLS) guidelines. The inhibitory effect of curcumin on the cell adhesion was performed with Candida species and BEC. RESULTS: Paracoccidioides brasiliensis isolates were the most susceptible to curcumin while the growth of Aspergillus isolates was not affected. Curcumin was much more efficient than fluconazole in inhibiting the adhesion of Candida species to BEC, particularly those strains isolated from the buccal mucosa of AIDS patients. CONCLUSIONS: The lack of antifungal compounds with reduced side effects highlights the importance of studying natural products for this purpose. Curcumin was a more potent antifungal than fluconazole against P. brasiliensis, the causal agent of the neglected disease paracoccidioidomycosis. Curcumin dramatically inhibited the adhesion of Candida species isolated from AIDS patients to BEC, demonstrating that curcumin is a promising lead compound that warrants further investigation into its therapeutical use in immunocompromised patients.


Asunto(s)
Antifúngicos/farmacología , Curcumina/farmacología , Hongos/efectos de los fármacos , Adhesión Celular/efectos de los fármacos , Células Cultivadas , Células Epiteliales/microbiología , Humanos , Pruebas de Sensibilidad Microbiana
10.
Sao Paulo Med J ; 118(1): 3-6, 2000 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-10685120

RESUMEN

CONTEXT: The menopause accelerates bone loss and is associated with an increased bone turnover. Bone formation may be evaluated by several biochemical markers. However, the establishment of an accurate marker for bone resorption has been more difficult to achieve. OBJECTIVE: To study the effect of hormone replacement therapy (HRT) on bone mass and on the markers of bone resorption: urinary excretion of pyridinoline and deoxypyridinoline. DESIGN: Cohort correlational study. SETTING: Academic referral center. SAMPLE: 53 post-menopausal women, aged 48-58 years. MAIN MEASUREMENTS: Urinary pyr and d-pyr were measured in fasting urine samples by spectrofluorometry after high performance liquid chromatography and corrected for creatinine excretion measured before treatment and after 1, 2, 4 and 12 months. Bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DEXA) before treatment and after 12 months of HRT. RESULTS: The BMD after HRT was about 4.7% (P < 0.0004); 2% (P < 0.002); and 3% (P < 0. 01) higher than the basal values in lumbar spine, neck and trochanter respectively. There were no significant correlations between pyridinium cross-links and age, weight, menopause duration and BMD. The decrease in pyr and d-pyr was progressive after HRT, reaching 28.9% (P < 0.0002), and 42% (P < 0.0002) respectively after 1 year. CONCLUSIONS: Urinary pyridinoline and deoxypyridinoline excretion decreases early in hormone replacement therapy, reflecting a decrease in the bone resorption rate, and no correlation was observed with the bone mass evaluated by densitometry.


Asunto(s)
Aminoácidos/orina , Densidad Ósea/efectos de los fármacos , Resorción Ósea/tratamiento farmacológico , Huesos/efectos de los fármacos , Terapia de Reemplazo de Hormonas , Absorciometría de Fotón , Biomarcadores/orina , Resorción Ósea/metabolismo , Resorción Ósea/orina , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad
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