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1.
An Acad Bras Cienc ; 94(2): e20210670, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35507982

RESUMEN

Fatty acid synthase (FASN) is the rate-limiting enzyme for the de novo synthesis of fatty acids in the cytoplasm of tumour cells. Many tumour cells express high levels of FASN, and its expression is associated with a poorer prognosis. Cervical cancer is a major public health problem, representing the fourth most common cancer affecting women worldwide. To date, only a few in silico studies have correlated FASN expression with cervical cancer. This study aimed to investigate in vitro FASN expression in premalignant lesions and cervical cancer samples and the effects of a FASN inhibitor on cervical cancer cells. FASN expression was observed in all cervical cancer samples with increased expression at more advanced cervical cancer stages. The FASN inhibitor (orlistat) reduced the in vitro cell viability of cervical cancer cells (C-33A, ME-180, HeLa and SiHa) in a time-dependent manner and triggered apoptosis. FASN inhibitor also led to cell cycle arrest and autophagy. FASN may be a potential therapeutic target for cervical cancer, and medicinal chemists, pharmaceutical researchers and formulators should consider this finding in the development of new treatment approaches for this cancer type.


Asunto(s)
Neoplasias del Cuello Uterino , Apoptosis , Línea Celular Tumoral , Supervivencia Celular , Ácido Graso Sintasas/metabolismo , Ácido Graso Sintasas/farmacología , Femenino , Humanos , Orlistat/farmacología , Neoplasias del Cuello Uterino/tratamiento farmacológico
2.
Cell Biochem Funct ; 39(6): 780-790, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34031899

RESUMEN

Stem-like cells (CSCs) have a tumour-initiating capacity and play critical role in tumour metastasis, relapse and resistance to therapy. The ectoenzyme CD73, encoded by the NT5E gene, which catalyses the hydrolysis of AMP into adenosine, has been associated to an immunosuppressive tumour microenvironment, tumour cell adhesion and migration. Therefore, we investigated the expression and activity of CD73 in sphere-forming cells from cervical cancer in comparison to monolayer cells in vitro. In addition, in silico analysis was performed to determine the expression of CD73 and other members of purinergic signalling in CSC-like population derived from different tumour types in comparison to monolayer cells. CD73 protein expression levels and functionality in SiHa cells were analysed by flow cytometry and enzymatic assay, respectively. In silico investigation was performed through the analysis of seven datasets from different tumour types using GEO database. In vitro analysis showed a decreased CD73 protein expression and enzymatic activity in cervical spheres, when compared to monolayers. In addition, when sphere-derived cells are re-plated as monolayer culture, the CD73 expression and activity are restored. Supporting the in vitro results, in silico analysis showed that three-dimensional spheres derived from cervical, thyroid and breast cancer presented decreased expression of CD73, when compared to their adherent counterparts. The decreased expression of CD73 in sphere-derived cells or CSC-enriched population reinforce its important role in cell adhesion, tumour spreading ability and metastasis, suggesting CD73 as potential target to be further investigated in cervical cancer.


Asunto(s)
5'-Nucleotidasa/genética , Microambiente Tumoral/genética , Neoplasias del Cuello Uterino/genética , 5'-Nucleotidasa/metabolismo , Femenino , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Humanos , Células Tumorales Cultivadas , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología
3.
Drug Dev Ind Pharm ; 47(10): 1556-1567, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34821528

RESUMEN

The use of polymeric blends is a potential strategy to obtain novel nanotechnological formulations aiming at drug delivery systems. Saquinavir, an antiretroviral drug, was chosen as a model drug for the development of new stable liquid formulations with unpleasant taste masking properties. Three formulations containing different polymeric ratios (1:3, 1:1 and 3:1) were prepared and properly characterized by particle size distribution, zeta potential, pH, drug content and encapsulation efficiency measurements. The stability was verified by monitoring the zeta potential, particle size distribution, polydispersity index and drug content by 90 days. The light backscattering analysis was used to early identify possible phenomena of instability in the formulations. The in vitro drug release and saquinavir cytotoxicity were evaluated. The in vitro and in vivo taste masking properties were studied using an electronic tongue and a human sensory panel. All formulations presented nanometric sizes around 200 nm and encapsulation efficiency above 99%. The parameters evaluated for stability remained constant throughout 90 days. The in vitro tests showed a controlled drug release and absence of toxic effects on human T lymphocytes. The electronic tongue experiment showed taste differences for all formulations in comparison to drug solutions, with a more pronounced difference for the formulation with higher polycaprolactone content (3:1). This formulation was chosen for in vivo sensory panel evaluation which results corroborated the electronic tongue experiments. In conclusion, the polymer blend nanoformulation developed herein showed the promising application to incorporate drugs aiming at pharmaceutical taste-masking properties.


Asunto(s)
Saquinavir , Gusto , Humanos , Preparaciones Farmacéuticas/química , Poliésteres , Polímeros , Saquinavir/farmacología
4.
Purinergic Signal ; 16(1): 29-40, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31955347

RESUMEN

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm, characterized by the occurrence of the t(9;22)(q34;q11) translocation. First-line therapy for CML consists of treatment with imatinib mesylate, which selectively inhibits the BCR-ABL protein by competing for its ATP-binding site. Adenine nucleotide signaling is modulated by the ectonucleotidases and this pathway is related to tumorigenic processes. Considering the relationship between ATP and cancer, we aimed to evaluate the influence of imatinib mesylate on the expressions and functions of the NTPDase and ecto-5'-nucleotidase (CD73) enzymes in imatinib-sensitive and -resistant K-562 cell lines. mRNA analysis showed that K-562 cells express all ENTPDs and NT5E. However, when treated with imatinib mesylate for 24 h, the expression of ENTPD1, -2, -3 and -5 increased, leading to a higher nucleotides hydrolysis rate. HPLC analysis identified increased ATP degradation in cells after 24 h of treatment, with consequent ADP and AMP formation, corroborating the increase in gene and protein expression of ectonucleotidases as observed in previous results. On the other hand, we observed that imatinib-resistant K-562 cells presented a decrease in nucleotide hydrolysis and expressions of ENTPD1 and -5. These results suggest an involvement of imatinib in modulating ectonucleotidases in CML that will need further investigation. Since these ectonucleotidases have important catalytic activities in the tumor microenvironment, their modulation in CML cells may represent an important therapeutic approach to regulate levels of extracellular adenine nucleotides.


Asunto(s)
Adenosina Trifosfato/metabolismo , Antineoplásicos/farmacología , Mesilato de Imatinib/farmacología , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Pirofosfatasas/metabolismo , Línea Celular Tumoral , Humanos , Pirofosfatasas/efectos de los fármacos
5.
Drug Dev Ind Pharm ; 45(1): 63-66, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30230390

RESUMEN

OBJECTIVE: To evaluate, for the first time, the use of SCC4 cell monolayers as an alternative sublingual barrier model and study the influence of nanoencapsulation on carvedilol transport across SCC4 cell monolayers. SIGNIFICANCE: The sublingual cavity is an interesting route for administration of drugs with limited oral bioavailability due to hepatic first pass metabolism. By this route, the drug is directly absorbed into blood circulation. In this sense, mucoadhesive carvedilol-loaded nanocapsules (CAR-NC) were previously proposed for the administration of this drug by sublingual route. Carvedilol is used for cardiovascular diseases and suffers metabolism in liver when orally administrated. Nanoencapsulation of carvedilol controlled its permeation across porcine sublingual mucosa. METHODS: Carvedilol-loaded cationic nanocapsules were prepared by interfacial deposition of a preformed polymer. Drug permeation studies were carried out in Transwell® inserts. The integrity of cell monolayers after the drug transport was assessed by transepithelial electric resistance. Compatibility of the CAR-NC with the SCC4 cells was evaluated by the Sulforhodamine B assay. RESULTS: The drug permeated the cell monolayer by a controlled way when nanoencapsulated and this profile had a linear relation with those observed in porcine sublingual mucosa. The integrity of the cell monolayer was maintained after drug permeation and CAR-NC was no cytotoxic to SCC4 cells. CONCLUSION: Nanoencapsulated carvedilol permeated by a controlled and safe way by SCC4 cell monolayer. SCC4 cells monolayers may be used as in vitro model for sublingual drug transport studies in the development of novel formulations.


Asunto(s)
Antihipertensivos/síntesis química , Antihipertensivos/metabolismo , Carvedilol/síntesis química , Carvedilol/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Nanocápsulas/química , Administración Sublingual , Antihipertensivos/administración & dosificación , Transporte Biológico/efectos de los fármacos , Transporte Biológico/fisiología , Carvedilol/administración & dosificación , Humanos , Nanocápsulas/administración & dosificación , Células Tumorales Cultivadas
6.
Cell Biol Int ; 42(2): 139-152, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28949053

RESUMEN

Cervical cancer is the fourth most common cancer affecting women worldwide. Among many factors, the presence of cancer stem cells, a subpopulation of cells inside the tumor, has been associated with a worse prognosis. Considering the importance of gene expression studies to understand the biology of cervical cancer stem cells (CCSC), this work identifies stable reference genes for cervical cancer cell lines SiHa, HeLa, and ME180 as well as their respective cancer stem-like cells. A literature review was performed to identify validated reference genes currently used to normalize RT-qPCR data in cervical cancer cell lines. Then, cell lines were cultured in regular monolayer or in a condition that favors tumor sphere formation. RT-qPCR was performed using five reference genes: ACTB, B2M, GAPDH, HPRT1, and TBP. Stability was assessed to validate the selected genes as suitable reference genes. The evaluation validated B2M, GAPDH, HPRT1, and TBP in these experimental conditions. Among them, GAPDH and TBP presented the lowest variability according to the analysis by Normfinder, Bestkeeper, and ΔCq methods, being therefore the most adequate genes to normalize the combination of all samples. These results suggest that B2M, GAPDH, HPRT1, and TBP are suitable reference genes to normalize RT-qPCR data of established cervical cancer cell lines SiHa, HeLa, and ME180 as well as their derived cancer stem-like cells. Indeed, GAPDH and TBP seem to be the most convenient choices for studying gene expression in these cells in monolayers or spheres.


Asunto(s)
Células Madre Neoplásicas/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Neoplasias del Cuello Uterino/genética , Línea Celular Tumoral , Femenino , Células HeLa , Humanos , Células Madre Neoplásicas/patología , Estándares de Referencia , Esferoides Celulares , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología
7.
Pharm Res ; 34(2): 438-452, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27981451

RESUMEN

PURPOSE: This study was conducted a promising approach to surface functionalization developed for lipid-core nanocapsules and the merit to pursue new strategies to treat solid tumors. METHODS: Bromelain-functionalized multiple-wall lipid-core nanocapsules (Bro-MLNC-Zn) were produced by self-assembling following three steps of interfacial reactions. Physicochemical and structural characteristics, in vitro proteolytic activity (casein substrate) and antiproliferative activity (breast cancer cells, MCF-7) were determined. RESULTS: Bro-MLNC-Zn had z-average diameter of 135 nm and zeta potential of +23 mV. The complex is formed by a Zn-N chemical bond and a chelate with hydroxyl and carboxyl groups. Bromelain complexed at the nanocapsule surface maintained its proteolytic activity and showed anti-proliferative effect against human breast cancer cells (MCF-7) (72.6 ± 1.2% at 1.250 µg mL-1 and 65.5 ± 5.5% at 0.625 µg mL-1). Comparing Bro-MLNC-Zn and bromelain solution, the former needed a dose 160-folds lower than the latter for a similar effect. Tripan blue dye assay corroborated the results. CONCLUSIONS: The surface functionalization approach produced an innovative formulation having a much higher anti-proliferative effect than the bromelain solution, even though both in vitro proteolytic activity were similar, opening up a great opportunity for further studies in nanomedicine.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Bromelaínas/química , Bromelaínas/farmacología , Proliferación Celular/efectos de los fármacos , Lípidos/química , Nanocápsulas/química , Línea Celular Tumoral , Química Farmacéutica/métodos , Portadores de Fármacos/química , Femenino , Humanos , Células MCF-7 , Nanomedicina/métodos , Tamaño de la Partícula
8.
Phytother Res ; 31(1): 62-68, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27619474

RESUMEN

In this study, a phytochemical and biological investigation on five South Brazilian Hypericum species (Hypericum caprifoliatum, Hypericum carinatum, Hypericum connatum, Hypericum myrianthum, and Hypericum polyanthemum) was carried out. The phloroglucinol-enriched fractions (PEF) of the flowering aerial parts were analyzed by high-performance liquid chromatography for the content of uliginosin A (1), japonicin A (2), uliginosin B (3), hyperbrasilol B (4), and the three benzopyrans, that is, 6-isobutyryl-5,7-dimethoxy-2,2-dimethyl-benzopyran (HP1) (5), 7-hydroxy-6-isobutyryl-5-methoxy-2,2-dimethyl-benzopyran (HP2) (6), and 5-hydroxy-6-isobutyryl-7-methoxy-2,2-dimethyl-benzopyran (HP3) (7). After chemical characterization, the PEF were assayed for cell proliferation on human keratinocyte cell line by MTT. The H. carinatum and H. polyanthemum PEF demonstrated better results with an increase in cell proliferation (138.7% and 120.6%, respectively). The cell counting and Ki-67 assay with H. carinatum PEF confirmed the MTT results. The cell cycle distribution indicates an increase in the cells at S and G2/M phases, which is indicative of proliferation induction. In summary, the results indicate an induction of HaCaT proliferation by the treatment with H. carinatum PEF (at 10 and 15 µg/mL), suggesting a possible use as wound healing agent. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Hypericum/química , Extractos Vegetales/química , Brasil , Proliferación Celular , Humanos , Queratinocitos/efectos de los fármacos , Extractos Vegetales/farmacología
9.
Mol Pharmacol ; 90(3): 371-84, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27436127

RESUMEN

Autophagy is a catabolic process that is largely regulated by extracellular and intracellular signaling pathways that are central to cellular metabolism and growth. Mounting evidence has shown that ion channels and transporters are important for basal autophagy functioning and influence autophagy to handle stressful situations. Besides its role in cell proliferation and apoptosis, intracellular Ca(2+) is widely recognized as a key regulator of autophagy, acting through the modulation of pathways such as the mechanistic target of rapamycin complex 1, calcium/calmodulin-dependent protein kinase kinase 2, and protein kinase C. Proper spatiotemporal Ca(2+) availability, coupled with a controlled ionic flow among the extracellular milieu, storage compartments, and the cytosol, is critical in determining the role played by Ca(2+) on autophagy and on cell fate. The crosstalk between Ca(2+) and autophagy has a central role in cellular homeostasis and survival during several physiologic and pathologic conditions. Here we review the main findings concerning the mechanisms and roles of Ca(2+)-modulated autophagy, focusing on human disorders ranging from cancer to neurologic diseases and immunity. By identifying mechanisms, players, and pathways that either induce or suppress autophagy, new promising approaches for preventing and treating human disorders emerge, including those based on the modulation of Ca(2+)-mediated autophagy.


Asunto(s)
Autofagia , Señalización del Calcio , Enfermedad , Calcio/metabolismo , Sistema Nervioso Central/metabolismo , Humanos , Modelos Biológicos
10.
Tumour Biol ; 37(6): 7059-73, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26943912

RESUMEN

Dipeptidyl peptidase IV (DPPIV/CD26) is a multifunctional protein with intrinsic peptidase activity that inactivates or degrades some bioactive peptides. It is the main cellular binding protein for ecto-adenosine deaminase and interacts with extracellular matrix proteins, besides participating in different signaling pathways. Due to these multiple functions, DPPIV/CD26 has been shown to be closely related to the tumor process. It has been reported that the progression of certain types of cancer is accompanied by a decrease in DPPIV/CD26 expression, and studies have shown that the malignant phenotype can be reverted when DPPIV/CD26 expression is induced in these cancer cells, characterizing this protein as a tumor suppressor. On the other hand, DPPIV/CD26 was described as a protein associated with invasion and metastatic spread, characterizing it as a marker of malignancy. Thus, this review explores the roles of DPPIV/CD26 expression in tumor progression in different types of cancer and demonstrates the importance of this protein as a promising therapeutic target and tumor biomarker.


Asunto(s)
Biomarcadores/metabolismo , Dipeptidil Peptidasa 4/metabolismo , Genes Supresores de Tumor , Neoplasias/diagnóstico , Neoplasias/metabolismo , Humanos
11.
Mem Inst Oswaldo Cruz ; 111(2): 106-13, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26841046

RESUMEN

The influence of different infectious agents and their association with human papillomavirus (HPV) in cervical carcinogenesis have not been completely elucidated. This study describes the association between cytological changes in cervical epithelium and the detection of the most relevant aetiological agents of sexually transmitted diseases. Samples collected from 169 patients were evaluated by conventional cytology followed by molecular analysis to detect HPV DNA, Chlamydia trachomatis, herpes simplex virus 1 and 2,Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis, andTreponema pallidum, besides genotyping for most common high-risk HPV. An association between cytological lesions and different behavioural habits such as smoking and sedentariness was observed. Intraepithelial lesions were also associated with HPV and C. trachomatis detection. An association was also found between both simple and multiple genotype infection and cytological changes. The investigation of HPV and C. trachomatisproved its importance and may be considered in the future for including in screening programs, since these factors are linked to the early diagnosis of patients with precursor lesions of cervical cancer.


Asunto(s)
Cuello del Útero/microbiología , Chlamydia trachomatis/aislamiento & purificación , ADN Viral/aislamiento & purificación , Papillomaviridae/aislamiento & purificación , Lesiones Intraepiteliales Escamosas de Cuello Uterino/microbiología , Neoplasias del Cuello Uterino/prevención & control , Adolescente , Adulto , Carcinogénesis , Cuello del Útero/patología , Infecciones por Chlamydia/complicaciones , Infecciones por Chlamydia/epidemiología , Coinfección , Estudios Transversales , Efecto Citopatogénico Viral , Detección Precoz del Cáncer/métodos , Epitelio/virología , Femenino , Genotipo , Técnicas de Genotipaje , Herpesvirus Humano 1/aislamiento & purificación , Herpesvirus Humano 2/aislamiento & purificación , Humanos , Persona de Mediana Edad , Tipificación Molecular , Mycoplasma genitalium/aislamiento & purificación , Neisseria gonorrhoeae/aislamiento & purificación , Papillomaviridae/clasificación , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Factores de Riesgo , Treponema pallidum/aislamiento & purificación , Trichomonas vaginalis/aislamiento & purificación , Neoplasias del Cuello Uterino/microbiología , Adulto Joven
12.
Biochem Cell Biol ; 92(2): 95-104, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24697693

RESUMEN

Cervical cancer is the third most frequent cancer in women worldwide. Adenine nucleotide signaling is modulated by the ectonucleotidases that act in sequence, forming an enzymatic cascade. Considering the relationship between the purinergic signaling and cancer, we studied the E-NTPDases, ecto-5'-nucleotidase, and E-NPPs in human cervical cancer cell lines and keratinocytes. We evaluated the expression profiles of these enzymes using RT-PCR and quantitative real-time PCR analysis. The activities of these enzymes were examined using ATP, ADP, AMP, and p-nitrophenyl-5'-thymidine monophosphate (p-Nph-5'-TMP) as substrate, in a colorimetric assay. The extracellular adenine nucleotide hydrolysis was estimated by HPLC analysis. The hydrolysis of all substrates exhibited a linear pattern and these activities were cation-dependent. An interesting difference in the degradation rate was observed between cervical cancer cell lines SiHa, HeLa, and C33A and normal imortalized keratinocytes, HaCaT cells. The mRNA of ecto-5'-nucleotidase, E-NTPDases 5 and 6 were detectable in all cell lines, and the dominant gene expressed was the Entpd 5 enzyme, in SiHa cell line (HPV16 positive). In accordance with this result, a higher hydrolysis activity for UDP and GDP nucleotides was observed in the supernatant of the SiHa cells. Both normal and cancer cells presented activity and mRNAs of members of the NPP family. Considering that these enzymes exert an important catalytic activity, controlling purinergic nucleotide concentrations in tumors, the presence of ectonucleotidases in cervical cancer cells can be important to regulate the levels of extracellular adenine nucleotides, limiting their effects.


Asunto(s)
5'-Nucleotidasa/metabolismo , Hidrolasas Diéster Fosfóricas/metabolismo , Pirofosfatasas/metabolismo , Neoplasias del Cuello Uterino/metabolismo , 5'-Nucleotidasa/genética , Nucleótidos de Adenina/metabolismo , Línea Celular Tumoral , Membrana Celular/metabolismo , Femenino , Expresión Génica , Humanos , Hidrólisis , Hidrolasas Diéster Fosfóricas/genética , Pirofosfatasas/genética , ARN Mensajero/metabolismo , Neoplasias del Cuello Uterino/genética
13.
Molecules ; 18(9): 11022-32, 2013 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-24022763

RESUMEN

Baccharis trimera is used in folk medicine as a tea for digestive and liver diseases. It possesses anti-inflammatory and antioxidant properties that are related to the presence of phenolic compounds. The aim of this work was to investigate the anti-proliferative properties of phenolic (PHE) and terpenoid (SAP) compounds from B. trimera on human cervical cancer. The treatment of SiHa cells with PHE for 24 h suppressed colony formation in a dose-dependent manner, inhibited proliferation and inhibited cell motility. Although SAP inhibited the proliferation of SiHa cells in a dose-dependent manner, it increased colony formation and did not inhibit cell motility. PHE and SAP also promoted a significant increase in lactate dehydrogenase levels in the culture medium in a dose-dependent manner, indicating a loss of cell membrane integrity. Moreover, PHE promoted necrotic cell death, whereas SAP induced apoptosis. These compounds are new anticancer prototypes due their significant anticancer activity demonstrated herein.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Baccharis/química , Fenoles/farmacología , Extractos Vegetales/farmacología , Terpenos/farmacología , Antineoplásicos Fitogénicos/aislamiento & purificación , Apoptosis , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Concentración 50 Inhibidora , L-Lactato Deshidrogenasa/metabolismo , Necrosis , Fenoles/aislamiento & purificación , Componentes Aéreos de las Plantas/química , Extractos Vegetales/aislamiento & purificación , Terpenos/aislamiento & purificación
14.
Pharmaceuticals (Basel) ; 16(4)2023 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-37111343

RESUMEN

Chronic myeloid leukemia (CML) is a myeloproliferative disease characterized by the formation of the BCR-ABL (breakpoint cluster region-Abelson) oncoprotein. As many patients display therapeutic resistance, the development of new drugs based on semisynthetic products represents a new potential therapeutic approach for treating the disease. In this study, we investigated the cytotoxic activity, possible mechanism of action of a hybrid compound of betulinic acid (BA) and brosimine B in CML cell lines that are sensitive (K-562) and resistant (K-562R) to imatinib, in addition to evaluating lower doses of imatinib in combination with the hybrid compound. The effects of the compound, and its combination with imatinib, on apoptosis, cell cycle, autophagy and oxidative stress were determined. The compound was cytotoxic in K-562 (23.57 ± 2.87 µM) and K-562R (25.80 ± 3.21 µM) cells, and a synergistic effect was observed when it was associated with imatinib. Apoptosis was mediated by the caspase 3 and 9 intrinsic pathway, and cell cycle evaluation showed arrest at G0/G1. In addition, the hybrid compound increased the production of reactive oxygen species and induced autophagy by increasing LC3II and Beclin-1 mRNA levels. Results suggest that this hybrid compound causes the death of both imatinib-sensitive and -resistant cell lines and may hold potential as a new anticancer treatment against CML.

15.
Mutat Res ; 746(1): 42-8, 2012 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-22405974

RESUMEN

Toluene is an organic solvent used in numerous processes and products, including industrial paints. Toluene neurotoxicity and reproductive toxicity are well recognized; however, its genotoxicity is still under discussion, and toluene is not classified as a carcinogenic solvent. Using the comet assay and the micronucleus test for detection of possible genotoxic effects of toluene, we monitored industrial painters from Rio Grande do Sul, Brazil. The putative involvement of oxidative stress in genetic damage and the influences of age, smoking, alcohol consumption, and exposure time were also assessed. Although all biomarkers of toluene exposure were below the biological exposure limits, painters presented significantly higher DNA damage (comet assay) than the control group; however, in the micronucleus assay, no significant difference was observed. Painters also showed alterations in hepatic enzymes and albumin levels, as well as oxidative damage, suggesting the involvement of oxidative stress. According to multiple linear regression analysis, blood toluene levels may account for the increased DNA damage in painters. In summary, this study showed that low levels of toluene exposure can cause genetic damage, and this is related to oxidative stress, age, and time of exposure.


Asunto(s)
Daño del ADN/efectos de los fármacos , Mutágenos/toxicidad , Exposición Profesional , Estrés Oxidativo/efectos de los fármacos , Pintura/toxicidad , Tolueno/toxicidad , Adulto , Factores de Edad , Consumo de Bebidas Alcohólicas/efectos adversos , Ensayo Cometa , Humanos , Peroxidación de Lípido/genética , Masculino , Pruebas de Micronúcleos , Especies Reactivas de Oxígeno/análisis , Fumar/efectos adversos , Factores de Tiempo
16.
J Enzyme Inhib Med Chem ; 27(1): 29-36, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21534863

RESUMEN

In this study, we have reported the kinetic and biochemical characterization of ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) activity in rat cardiac fractions, one soluble and the other enriched in vesicles derived from sarcoplasmic reticulum. Both fractions demonstrated E-NPP activities, which could be observed by extracellular hydrolysis of p-nitrophenyl-5'-thymidine monophosphate (p-Nph-5'-TMP) and other biochemical characteristics. The K(M) values for the hydrolysis of p-Nph-5'-TMP in soluble and microsomal fractions were 118.53 ± 27.28 and 91.92 ± 12.49 µM, respectively. The V(max) values calculated were 2.56 ± 0.15 and 113.87 ± 21.09 nmol p-nitrophenol/min/mg of protein in soluble and microsomal fractions, respectively. Among the compounds tested to evaluate the possible activity of other enzymes on p-Nph-5'-TMP hydrolysis, only suramin (0.25 mM) produced a significant inhibition of substrate hydrolysis. Thus, our results strongly suggest the presence of E-NPP enzymes in subcellular fractions of rat heart, which could be involved in nucleotide signalling in the cardiac tissue.


Asunto(s)
Ventrículos Cardíacos/enzimología , Microsomas/enzimología , Hidrolasas Diéster Fosfóricas/metabolismo , Pirofosfatasas/metabolismo , Animales , Hidrólisis , Masculino , Pirofosfatasas/antagonistas & inhibidores , Ratas , Ratas Wistar , Retículo Sarcoplasmático/enzimología , Solubilidad , Relación Estructura-Actividad , Suramina/farmacología
17.
Nat Prod Res ; 35(22): 4648-4652, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31797681

RESUMEN

The genus Hypericum (Hypericaceae) is a recognized source of therapeutic agents, being some species widely used due to their wound healing properties. In a previous study, south Brazilian species H. caprifoliatum, H. carinatum, H. connatum, H. myrianthum and H. polyanthemum demonstrated potential to induce proliferation of keratinocytes. In the present study, the effect of phloroglucinol derivatives isolated from Hypericum on cell proliferation of human keratinocytes, fibroblasts and stem cells was investigated. The best results, determined by the MTT assay, were achieved with cariphenone B at concentrations of 0.01 and 0.1 µM (122.3% and 114%, respectively) on HaCaT cells. Uliginosin B was able to induce the proliferation of mesenchymal stem cells (129% at 10 µM) and MRC5 fibroblasts (152.5% at 5 µM). These findings confirm the capacity of phloroglucinol derivatives to induce the in vitro cellular proliferation and reinforce the importance of Hypericum species as potential sources of wound healing compounds.


Asunto(s)
Hypericum , Proliferación Celular , Humanos , Floroglucinol/farmacología , Extractos Vegetales/farmacología , Cicatrización de Heridas
18.
Chem Biol Interact ; 344: 109535, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34051208

RESUMEN

Imatinib, a specific Bcr-Abl tyrosine kinase inhibitor, is the most commonly used drug in the treatment of chronic myeloid leukemia. However, optimal response is not achieved in up to 33% of patients. Therefore, development of novel therapeutic strategies for chronic myeloid leukemia is critical. Betulinic (1) and ursolic (2) acids are natural pentacyclic triterpenes that exhibit antileukemic activities. In this study, we evaluated the effects of pharmacomodulations at the C-3 position of the triterpene moiety of betulinic and ursolic acids on their activity against K562 leukemia cells. Six new derivatives (1a-2c) were synthesized and evaluated for pro-apoptotic and anti-proliferative effects in mammalian and leukemic cells. 2c derivative containing an amine group at the C-3 position of ursolic acid was the most active against leukemia cells with an IC50 value of 5.2 µM after 48 h of treatment. 2c did not exhibit cytotoxic effects against VERO and HepG2 cells and human lymphocytes, showing a good selectivity index for cancer over normal cells. Induced cell death by apoptosis via caspases 3 and 8, and also caused cell cycle arrest as evidenced by accumulation of cells in the G1 phase and decreased cell population in the G2 phase. Furthermore, co-treatment of 2c with imatinib, the chemotherapy drug most commonly used to treat leukemia, resulted in a synergistic effect. Our findings provide a strong rationale for further investigation of combination therapy using the 2c derivative and imatinib in pre-clinical studies.


Asunto(s)
Antineoplásicos/farmacología , Mesilato de Imatinib/farmacología , Triterpenos/farmacología , Animales , Antineoplásicos/síntesis química , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Caspasa 8/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Chlorocebus aethiops , Ensayos de Selección de Medicamentos Antitumorales , Sinergismo Farmacológico , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Triterpenos/síntesis química , Células Vero , Ácido Ursólico
19.
Mater Sci Eng C Mater Biol Appl ; 117: 111315, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32919675

RESUMEN

This research has aimed to improve the stability and taste-masking properties by developing nanostructured dosage forms containing Saquinavir. Liquid formulations were developed using Eudragit RS100® and Pullulan as polymers. The physicochemical characteristics, stability, in vitro drug release, morphology, mucoadhesion and taste masking capacity were evaluated. The Saquinavir-nanoparticles had average diameters between 136 and 158 nm, with a Span below 1.4. These formulations presented a drug content above 80%, a high encapsulation efficiency (>97%), slightly acidic pH levels, low dynamic viscosity and controlled drug release. Electron microscopy revealed irregular spherical nanoparticles. The formulations prepared with higher amounts of Eudragit RS100® had greater mucoadhesion. Both polymers were able to improve drug stabilization, taste-masking properties and protection against drug cytotoxicity. The Saquinavir-nanoparticles exhibited stability and control releasing properties, thus making it a promising liquid dosage form with taste-masking properties intended for application in pediatric treatment.


Asunto(s)
Nanopartículas , Saquinavir , Administración Oral , Niño , Composición de Medicamentos , Liberación de Fármacos , Humanos , Saquinavir/farmacología , Solubilidad , Gusto
20.
Anticancer Agents Med Chem ; 20(5): 622-633, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31976847

RESUMEN

BACKGROUND: Cancer is a multifactorial disease, representing one of the leading causes of death worldwide. On a global estimate, breast cancer is the most frequently occurring cancer in women and cervical cancer, the fourth most common. Both types of cancer remain the major cause of cancer-related mortality in developing countries. A strategy for rational drug design is hybridization, which aims to bring together in one molecule, two or more pharmacophores in order to reach several biological targets. OBJECTIVE: The objective of this work was to develop new hybrids based on natural pharmacophores: Betulinic acid (1) and brosimine b (2), active in female cancer cell lines. METHODS: The coupling reactions were carried out by Steglich esterification. Different compounds were designed for the complete and simplified structural hybridization of molecules. The anticancer activities of the compounds were evaluated in human cervical adenocarcinoma (HeLa), human cervical metastatic epidermoid carcinoma (ME-180), and human breast adenocarcinoma (MCF-7) cell lines. RESULTS: Hybrid 3 presented higher potency (IC50 = 9.2 ± 0.5µM) and SI (43.5) selectively in MCF-7 cells (in relation to Vero cells) with its cytotoxic effect occurring via apoptosis. In addition, compound 6 showed activity in MCF-7 and HeLa cells with intermediate potency, but with high efficacy, acting via apoptosis as well. CONCLUSION: In this context, we showed that the combination of two complex structures generated the development of hybrids with differing inhibitory profiles and apoptotic modes of action, thus representing potential alternatives in female cancer treatment.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Flavonoides/farmacología , Triterpenos Pentacíclicos/farmacología , Antineoplásicos Fitogénicos/síntesis química , Antineoplásicos Fitogénicos/química , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Flavonoides/síntesis química , Flavonoides/química , Células HeLa , Humanos , Conformación Molecular , Moraceae/química , Triterpenos Pentacíclicos/síntesis química , Triterpenos Pentacíclicos/química , Plantas Medicinales/química , Relación Estructura-Actividad , Células Tumorales Cultivadas , Ácido Betulínico
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