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1.
Int J Biol Macromol ; 269(Pt 1): 132071, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38705334

RESUMO

Wound healing is a challenging clinical problem and efficient wound management is essential to prevent infection. This is best done by utilizing biocompatible materials in order to complete the healing in a rapid manner, with functional and esthetic outcomes. In this context, the zein protein fulfills the criteria of the ideal wound dressing which include non-toxicity and non-inflammatory stimulation. Zein gels containing rutin were prepared without any chemical refinement or addition of gelling agents in order to obtain a natural formulation characterized by antioxidant and anti-inflammatory properties to be proposed for the treatment of burns and sores. In vitro scratch assay showed that the proposed gel formulations promoted cell migration and a rapid gap closure within 24 h (~90 %). In addition, the in vivo activities of rutin-loaded zein gel showed a greater therapeutic efficacy in Wistar rats, with a decrease of the wound area of about 90 % at day 10 with respect to the free form of the bioactive and to DuoDERM®. The evaluation of various markers (TNF-α, IL-1ß, IL-6, IL-10) confirmed the anti-inflammatory effect of the proposed formulation. The results illustrate the feasibility of exploiting the peculiar features of rutin-loaded zein gels for wound-healing purposes.

2.
Life (Basel) ; 13(11)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-38004247

RESUMO

BACKGROUND: Temporomandibular joint (TMJ) disorders, which affect millions of people worldwide, have multiple etiological factors that make an accurate diagnosis and effective treatments difficult. As a consequence, the gold standard diagnostic criteria for TMJ disorders remain elusive and often depend on subjective decisions. AIM: In this context, the lack of a non-invasive quantitative methodology capable of assessing the functional physiological state and, consequently, identifying risk indicators for the early diagnosis of TMJ disorders must be tackled and resolved. METHODOLOGY: In this work, we have studied the biomechanics and viscoelastic properties of the functional masticatory system by a non-invasive approach involving 52 healthy subjects, analysed by statistical-physics analysis applied to myotonic measurements on specific points of the masticatory system designing a TMJ network composed of 17 nodes and 20 links. RESULTS: We find that the muscle tone and viscoelasticity of a specific cycle linking frontal, temporal, and mandibular nodes of the network play a prominent role in the physiological functionality of the system. At the same time, the functional state is characterised by a landscape of nearly degenerated levels of elasticity in all links of the network, making this parameter critically distributed and deviating from normal behaviour. CONCLUSIONS: Time evolution and dynamic correlations between biomechanics and viscoelastic parameters measured on the different cycles of the network provide a quantitative framework associated with the functional state of the masticatory system. Our results are expected to contribute to enriching the taxonomy of this system, primarily based on clinical observations, patient symptoms, and expert consensus.

3.
Mater Sci Eng C Mater Biol Appl ; 118: 111538, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255091

RESUMO

In the last few decades, several natural and synthetic polymers have been used as starting material for the development of innovative polymeric nanoparticles able to encapsulate biologically active substances and to modulate their biopharmaceutical features and/or therapeutic efficacy. This investigation focused on the comparison of the physico-chemical properties of nanosystems made up of two of the most successfully used biodegradable biomaterials, namely poly(lactic-co-glycolic acid) (PLGA) and zein, belonging to the synthetic and natural family of polymers, respectively. Rutin, a polyphenolic bioflavonoid characterized by peculiar antioxidant properties, was chosen as the model drug to be encapsulated in the polymeric systems. The results demonstrated a greater ability of zein-based nanosystems to effectively retain the active compound with respect to the PLGA particles. The integration of rutin in the protein matrix favored a controlled drug leakage, and was influenced by the surfactant used to stabilize the formulation. Moreover, rutin-loaded zein nanoparticles showed significant in vitro antioxidant activity, evidencing a synergistic action between the intrinsic antioxidant activity of the protein and the pharmacological properties of the active compound. Finally, the intracellular localization of the zein nanosystems was demonstrated through confocal laser scanning microscopy.


Assuntos
Nanopartículas , Zeína , Portadores de Fármacos , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros , Rutina
4.
Transl Oncol ; 12(8): 1045-1055, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31163384

RESUMO

Ovarian cancer is the second most common gynecological malignancy worldwide. Paclitaxel is particularly important in the therapy of ovarian carcinomas, but the treatment efficacy is counteracted by the development of resistance to chemotherapy. The identification of target molecules that can prevent or control the development of chemoresistance might provide important tools for the management of patients affected by ovarian cancer. Serum- and glucocorticoid-regulated kinase 1 (SGK1) appears to be a key determinant of resistance to chemo- and radiotherapy. Specifically, SGK1 affects paclitaxel sensitivity in RKO colon carcinoma cells by modulating the specificity protein 1 (SP1)-dependent expression of Ran-specific GTPase-activating protein (RANBP1), a member of the GTP-binding nuclear protein Ran (RAN) network that is required for the organization and function of the mitotic spindle. SGK1 inhibition might thus be useful for counteracting the development of paclitaxel resistance. Here, we present in vitro data obtained using ovarian carcinoma cell lines that indicate that the SGK1 inhibitor SI113 inhibits cancer cell proliferation, potentiates the effects of paclitaxel-based chemotherapy, counteracts the development of paclitaxel resistance, and restores paclitaxel sensitivity in paclitaxel-resistant A2780 ovarian cancer cells. The results were corroborated by preclinical studies of xenografts generated in nude mice through the implantation of paclitaxel-resistant human ovarian cancer cells. The SGK1 inhibitor SI113 synergizes with paclitaxel in the treatment of xenografted ovarian cancer cells. Taken together, these data suggest that SGK1 inhibition should be investigated in clinical trials for the treatment of paclitaxel-resistant ovarian cancer.

5.
Carbohydr Polym ; 212: 430-438, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30832877

RESUMO

The development of innovative strategies for the efficacious treatment of inflammatory bowel diseases (IBD) still remains a goal for pharmaceutical research. Targeting the lower section of the intestine is the main aim of therapy because it is the compartment primarily affected by IBDs. Mesalazine was microencapsulated in chitosan particles in order to modulate its unfavorable pharmacokinetic profile exploiting the bioadhesive feature of the polysaccharide and increase the anti-inflammatory effect of the drug following its rectal administration in an in vivo model of induced IBD. The chitosan microparticles (1-4 µm mean size) allowed efficient retention of the mesalazine and a prolonged drug release lasting up to 48 h. In vitro and in vivo experiments confirmed the significant mucoadhesion feature of the formulation by means of mucin assay and CLSM experiments and demonstrated its therapeutic efficacy at a drug concentration 2-fold lower than the commercial formulation Asamax® (13 mg/kg vs 26 mg/kg).


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Quitosana/administração & dosagem , Doenças Inflamatórias Intestinais/tratamento farmacológico , Mesalamina/administração & dosagem , Microesferas , Administração Retal , Animais , Anti-Inflamatórios não Esteroides/química , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Quitosana/química , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Sulfato de Dextrana/toxicidade , Humanos , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/metabolismo , Mesalamina/química , Camundongos , Distribuição Aleatória , Resultado do Tratamento
6.
Artigo em Inglês | MEDLINE | ID: mdl-29615982

RESUMO

Many reports indicate that the protective action of nutraceuticals in the Mediterranean diet, against metabolic and cardiovascular diseases, can be attributed to the action of polyphenolic components of extra-virgin olive oil (EVOO). Here, we evaluated the protective effects of oleacein, one of the most abundant secoiridoids in EVOO, on the damages/metabolic alterations caused by high-fat diet (HFD) in male C57BL/6JolaHsd mice. After 5 weeks of treatment with 20 mg/kg of oleacein, body weight, glycemia, insulinemia, serum lipids, and histologic examination of liver tissue indicated a protective action of oleacein against abdominal fat accumulation, weight gain, and liver steatosis, with improvement of insulin-dependent glucose and lipid metabolism. Both serum parameters and hepatic histologic examination were altered in mice fed with HFD. By contrast, in the animals that received oleacein, plasma glucose, cholesterol and triglyceride serum levels, and liver histology were similar to controls fed with normocaloric diet. In addition, protein levels of FAS, SREBP-1, and phospho-ERK in liver were positively modulated by oleacein, indicating an improvement in liver insulin sensitivity. In a group of obese mice, treatment with oleacein determined a light, but still significant reduction of the increase in body weight, mainly due to lesser liver steatosis enlargement, associated with reduced levels of SREBP-1 and phospho-ERK and lower levels of total serum cholesterol; in these animals, altered plasma glucose and triglyceride serum levels were not reverted by oleacein. These results indicate that HFD-related hepatic insulin resistance may be partially prevented by oral administration of oleacein, suggesting a protective role of this nutraceutical against diet-dependent metabolic alterations. Additional studies are necessary to check whether oleacein can be used as an adjuvant to improve insulin sensitivity in humans.

7.
Pensando fam ; 21(1): 162-175, jul. 2017.
Artigo em Português | LILACS | ID: biblio-895224

RESUMO

Embora o que se entenda como infidelidade varie de acordo com o contexto sociocultural e o contrato estabelecido por cada casal, seu impacto na relação costuma ser significativo e desafiador. Neste artigo, serão abordadas possibilidades de intervenção junto a casais que buscam terapia em virtude da infidelidade conjugal. É importante considerar a infidelidade como um fenômeno complexo, relacionado a questões intrapsíquicas, relacionais, situacionais e socioculturais. O terapeuta deve abordar (a) o impacto inicial da descoberta da infidelidade; (b) a história da relação, de forma a contextualizar o acontecido; e (c) o seu futuro. Nesse processo, mostram-se úteis tanto sessões individuais como conjugais. O entendimento da infidelidade requer um olhar sistêmico, que consiga abranger a história do casal e da família, suas crenças e seus padrões relacionais. O terapeuta precisa ser capaz de criar um ambiente de compreensão mútua que possibilite as mudanças desejadas pelos cônjuges.(AU)


Although its meaning may differ according to specific socio-cultural contexts and to the established contract, infidelity always causes stress on couples' relationships and is very challenging to deal with. This article addresses possibilities of intervention when dealing with couples who seek therapy due to infidelity. It must be considered as a complex phenomenon, associated to intrapsychic, relational, situational and socio-cultural issues. Therapists must address: (a) the initial impact of the of infidelity revelation; (b) the history of the relationship, in order to contextualize what happened; and (c) what can be expected for the relationship's future. In this process, both individual and couples sessions are useful. Understanding infidelity requires a systemic approach, which should consider the history of the couple and of their family; their beliefs and their relational patterns. Therapists should be able to create an environment of mutual understanding thus contributing to the changes desired by the spouses.(AU)


Assuntos
Humanos , Relações Extramatrimoniais/psicologia , Terapia Conjugal/métodos , Casamento/psicologia , Conflito Familiar/psicologia
8.
Carbohydr Polym ; 152: 583-591, 2016 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-27516307

RESUMO

Rutin was microencapsulated in a chitosan matrix using the spray-drying technique and the resulting system was investigated. High amounts of rutin were efficiently entrapped within polymeric microspheres, and these microparticles were characterized by a smooth surface and afforded a controlled release of the active compound. The anti-inflammatory activity of rutin-loaded microspheres was investigated in in vitro models of NCTC 2544 and C-28 cells treated with LPS by determining the levels of IL-1ß and IL-6. The rutin-loaded microspheres showed an increase of in vitro anti-inflammatory activity with respect to the free active compound. Confocal laser scanning microscopy demonstrated that massive intracellular uptake of the chitosan microspheres took place after a few hours of incubation and that the drug was localized in the cytosol compartment of the treated cells. The improved anti-inflammatory activity of the rutin-loaded microspheres was further confirmed by an in vivo model of carrageenan-induced paw edema.


Assuntos
Anti-Inflamatórios , Quitosana , Portadores de Fármacos , Microesferas , Rutina , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Linhagem Celular , Quitosana/química , Quitosana/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Rutina/química , Rutina/farmacologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-27303363

RESUMO

An increased incidence of obesity is registered worldwide, and its association with insulin resistance and type 2 diabetes is closely related with increased morbidity and mortality for cardiovascular diseases. A major clinical problem in the management of obesity is the non-adherence or low adherence of patients to a hypocaloric dietetic restriction. In this study, we evaluated in obese mice the effects of shifting from high-calorie foods to normal diet on insulin sensitivity. Male C57BL/6JOlaHsd mice (n = 20) were fed with high fat diet (HFD) for a 24-week period. Afterward, body weight, energy, and food intake were measured in all animals, together with parameters of insulin sensitivity by homeostatic model assessment of insulin resistance and plasma glucose levels in response to insulin administration. Moreover, in half of these mice, Glut4 mRNA levels were measured in muscle at the end of the high fat treatment, whereas the rest of the animals (n = 10) were shifted to normocaloric diet (NCD) for 10 weeks, after which the same analyses were carried out. A significant reduction of body weight was found after the transition from high to normal fat diet, and this decrease correlated well with an improvement in insulin sensitivity. In fact, we found a reduction in serum insulin levels and the recovery of insulin responsiveness in terms of glucose disposal measured by insulin tolerance test and Glut4 mRNA and protein expression. These results indicate that obesity-related insulin resistance may be rescued by shifting from HFD to NCD.

10.
J Transl Med ; 14(1): 133, 2016 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-27176720

RESUMO

BACKGROUND: Circulating tumor cells (CTCs) represent one of the most interesting target in improving diagnosis, prognosis and treatment. Herein we evaluate the possibility of using an emo-cytometric approach on the evaluation of the heterogeneous population of CTCs to improve personalized metastatic risk assessment. We benchmarked ex vivo behavior of distinct subsets of circulating colon tumor cells with correspondent clinical behavior of patients from which we isolated CTCs. METHODS: Isolation and CTC expansion were performed by a gradient protocol. In vitro characterization was determined by flow cytometry, immunofluorescence, western blotting and proteomic profiling. Cell sorter was performed with immunomagnetic beads. Confocal microscopy was used to evaluate tissue sections. Kaplan Mayer curves was cared for through Medcalc program. RESULTS: We collected heterogeneous CTCs, derived from the whole blood of seven patients affected by colon cancer, expressing CD133(pos)CD45(neg) (5 ± 1) and (2 ± 1) and CK20(pos)CD45(neg) of (29 ± 3) (11 ± 1) cells/ml in Dukes D and A stage respectively. Proliferation rate of 57 ± 16 %, expression for CXCR4(pos) of 18 ± 7 % and detectable levels of IL-6, IL-8 and SDF-1 cytokines in conditioned culture medium characterized short-time expanded-CTCs (eCTCs). ECTCs organized in tumor sphere were CD45(neg)CD133(pos) while in adhesion were CXCR4(pos)CK20(pos). These two subsets were separately injected in mice. The first group of xenografts developed superficial lesions within 2 weeks. In the second group, in absence of growing tumour, the survival of injected eCTCs was monitored through SDF-1 serum levels detection. The detection of human cancer cells expressing CK20, in mice tissues sections, suggested a different biological behaviour of injected eCTC-subsets: tumorigenic for the first and disseminating for the second. The benchmarking of the experimental data with the clinical course highlights that patients with prevalence of circulating cancer stem cells (CD45(neg)CD133(pos)) have a lower overall survival. Conversely, patients with prevalence of circulating differentiated cells (CXCR4(pos)CK20(pos)) have a low disease-free survival. CONCLUSION: On the basis of the heterogeneous composition and despite the low number of CTCs, it was possible to distinguish two subgroups of CTCs, suggesting a different clinical outcome. CTC-subsets detailing is useful to better define the metastatic-risk personalized score thus improving disease management and reducing patient care cost.


Assuntos
Biomarcadores Tumorais/metabolismo , Diferenciação Celular , Neoplasias do Colo/patologia , Células Neoplásicas Circulantes/patologia , Células-Tronco Neoplásicas/patologia , Medicina de Precisão , Medição de Risco , Adulto , Idoso , Animais , Adesão Celular , Ciclo Celular , Proliferação de Células , Forma Celular , Sobrevivência Celular , Citocinas/metabolismo , Feminino , Humanos , Masculino , Camundongos SCID , Pessoa de Meia-Idade , Metástase Neoplásica , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Nutr Biochem ; 26(9): 938-48, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26025327

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in industrialized countries. Defective autophagy of lipid droplets (LDs) in hepatocytes, also known as lipophagy, has recently been identified as a possible pathophysiological mechanism of NAFLD. Experimental and epidemiological evidence suggests that dietary polyphenols may prevent NAFLD. To address this hypothesis and analyze the underlying mechanisms, we supplemented bergamot polyphenol fraction (BPF) to cafeteria (CAF) diet-fed rats, a good model for pediatric metabolic syndrome and NAFLD. BPF treatment (50 mg/kg/day supplemented with drinking water, 3 months) potently counteracted the pathogenic increase of serum triglycerides and had moderate effects on blood glucose and obesity in this animal model. Importantly, BPF strongly reduced hepatic steatosis as documented by a significant decrease in total lipid content (-41.3% ± 12% S.E.M.), ultrasound examination and histological analysis of liver sections. The morphometric analysis of oil-red stained sections confirmed a dramatic reduction in LDs parameters such as total LD area (48.5% ± 15% S.E.M.) in hepatocytes from CAF+BPF rats. BPF-treated livers showed increased levels of LC3 and Beclin 1 and reduction of SQSTM1/p62, suggesting autophagy stimulation. Consistent with BPF stimulation of lipophagy, higher levels of LC3II were found in the LD subcellular fractions of BPF-expose livers. This study demonstrates that the liver and its lipid metabolism are the main targets of bergamot flavonoids, supporting the concept that supplementation of BPF is an effective strategy to prevent NAFLD.


Assuntos
Citrus/química , Suplementos Nutricionais , Modelos Animais de Doenças , Lipotrópicos/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Extratos Vegetais/uso terapêutico , Polifenóis/uso terapêutico , Animais , Fármacos Antiobesidade/uso terapêutico , Autofagia , Biomarcadores/sangue , Biomarcadores/metabolismo , Dieta Ocidental/efeitos adversos , Frutas/química , Humanos , Itália , Gotículas Lipídicas/diagnóstico por imagem , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/patologia , Fígado/diagnóstico por imagem , Fígado/metabolismo , Fígado/patologia , Síndrome Metabólica/etiologia , Síndrome Metabólica/fisiopatologia , Proteínas Associadas aos Microtúbulos/agonistas , Proteínas Associadas aos Microtúbulos/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/patologia , Obesidade/fisiopatologia , Obesidade/prevenção & controle , Distribuição Aleatória , Ratos Wistar , Ultrassonografia
12.
J Chromatogr A ; 1388: 79-86, 2015 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-25704771

RESUMO

This paper reports the validation of a quantitative high performance liquid chromatography-photodiode array (HPLC-PDA) method for the simultaneous analysis, in mouse plasma, of eperisone hydrochloride and paracetamol by protein precipitation using zinc sulphate-methanol-acetonitrile. The analytes were resolved on a Gemini C18 column (4.6 mm × 250 mm; 5 µm particle size) using a gradient elution mode with a run time of 15 min, comprising re-equilibration, at 60°C (± 1°C). The method was validated over the concentration range from 0.5 to 25 µg/mL for eperisone hydrochloride and paracetamol, in mouse plasma. Ciprofloxacin was used as Internal Standard. Results from assay validations show that the method is selective, sensitive and robust. The limit of quantification of the method was 0.5 µg/mL for eperisone hydrochloride and paracetamol, and matrix-matched standard curves showed a good linearity, up to 25 µg/mL with correlation coefficients (r(2))≥ 0.9891. In the entire analytical range the intra and inter-day precision (RSD%) values were ≤ 1.15% and ≤ 1.46% for eperisone hydrochloride, and ≤ 0.35% and ≤ 1.65% for paracetamol. For both analytes the intra and inter-day trueness (bias%) values ranged, respectively, from -5.33% to 4.00% and from -11.4% to -4.00%. The method was successfully tested in pharmacokinetic studies after oral administration in mouse. Furthermore, the application of this method results in a significant reduction in terms of animal number, dosage, and improvement in speed, rate of analysis, and quality of pharmacokinetic parameters related to serial blood sampling.


Assuntos
Acetaminofen/sangue , Cromatografia Líquida de Alta Pressão/métodos , Propiofenonas/sangue , Acetaminofen/administração & dosagem , Acetaminofen/farmacocinética , Administração Oral , Animais , Área Sob a Curva , Calibragem , Cromatografia Líquida de Alta Pressão/instrumentação , Camundongos , Camundongos Endogâmicos C57BL , Propiofenonas/administração & dosagem , Propiofenonas/farmacocinética , Padrões de Referência , Distribuição Tecidual , Estudos de Validação como Assunto
13.
Blood ; 116(2): 226-38, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20363775

RESUMO

B-cell lymphoma is a clonal expansion of neoplastic cells that may result in fatal outcomes. Here, we report the in vivo targeting and growth inhibition of aggressive A20 murine B-cell lymphoma by idiotype-specific peptide pA20-36. pA20-36 was selected from random peptide libraries and bound specifically to the B-cell receptor (BCR) of A20 cells in mice engrafted with A20 lymphoma, as shown by histology and positron emission tomographic analysis. BCR cross-linking of A20 cells with pA20-36 resulted in massive apoptosis of targeted tumor cells and in an increased survival of the diseased animals without any detectable evidence of toxicity. The pA20-36 treatment reverted the immune suppression of the tumor microenvironment as shown by reduced expression of vascular endothelial growth factor, interleukin-10, and transforming growth factor-beta cytokines together with a lower number of CD11b+Gr-1+ inhibitor myeloid-derived suppressor cells and Foxp3+CD4+ Treg cells. Furthermore, pA20-36 treatment was associated with an increased number of tumor-infiltrating, activated CD8+ T cells that exerted a tumor-specific cytolytic activity. These findings show that a short peptide that binds specifically to the complementarity-determining regions of the A20 BCR allows in vivo detection of neoplastic cells together with significant inhibition of tumor growth in vivo.


Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Imunoterapia/métodos , Linfoma de Células B/imunologia , Peptídeos/imunologia , Animais , Anticorpos Anti-Idiotípicos/uso terapêutico , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Especificidade de Anticorpos , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Separação Celular , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Idiótipos de Imunoglobulinas/imunologia , Linfoma de Células B/terapia , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Confocal , Biblioteca de Peptídeos , Peptídeos/uso terapêutico , Tomografia por Emissão de Pósitrons , Receptores de Antígenos de Linfócitos B/imunologia , Ressonância de Plasmônio de Superfície
14.
J Mol Med (Berl) ; 87(12): 1221-39, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19756449

RESUMO

Serum and glucocorticoid regulated kinase 1 (Sgk1) is a serine-threonine kinase that is activated by serum, steroids, insulin, vasopressin, and interleukin 2 at the transcriptional and post-translational levels. Sgk1 is also important in transduction of growth factors and steroid-dependent survival signals and may have a role in the development of resistance to cancer chemotherapy. In the present paper, we demonstrate that Sgk1 activates MDM2-dependent p53 ubiquitylation. The results were obtained in RKO cells and other cell lines by Sgk1-specific RNA silencing and were corroborated in an original mouse model as well as in transiently and in stably transfected HeLa cells expressing wild-type or dominant negative Sgk1 mutant. Sgk1 contributes to cell survival, cell-cycle progression, and epithelial de-differentiation. We also show that the effects of Sgk1 on the clonogenic potential of different cancer cells depend on the expression of wild-type p53. Since transcription of Sgk1 is activated by p53, we propose a finely tuned feedback model where Sgk1 down-regulates the expression of p53 by enhancing its mono- and polyubiquitylation.


Assuntos
Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Proteínas Imediatamente Precoces , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas c-mdm2 , Proteína Supressora de Tumor p53 , Animais , Morte Celular , Linhagem Celular , Células HeLa , Humanos , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transdução de Sinais , Transfecção , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
15.
Cancer Chemother Pharmacol ; 64(5): 1009-20, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19263052

RESUMO

Gemcitabine (GEM) is presently the standard option for the treatment of advanced pancreatic cancer (PC). We investigated the in vitro and in vivo antitumor potential of GEM-loaded PEGylated liposomes (L-GEM) as a novel agent for the treatment of PC. In vitro analysis of antitumor activity against human PC cell lines, BXPC-3 and PSN-1, showed a significant time- and dose-dependent reduction of cell viability following exposure to L-GEM as compared to free GEM [at 72 h, IC(50): 0.009 vs. 0.027 microM (P = 0.003) for BXPC-3 and 0.003 vs. 0.009 microM (P < 0.001) for PSN1, respectively]. Confocal laser scanning microscopy demonstrated an effective liposome/cell interaction and internalization process following 3-h cell exposure to L-GEM. The in vivo antitumor activity of L-GEM was investigated in a cohort of SCID mice bearing BxPC-3 or PSN-1 xenografts. Animals were i.p. treated with L-GEM (5 mg/kg), or a threefold increased dose of free GEM (15 mg/kg), or empty liposomes or vehicle, twice a week for 35 days. A significant higher inhibition of tumor growth in mice treated with L-GEM versus free GEM (P = 0.006 and P = 0.004 for BXPC-3 and PSN-1, respectively) or control groups (P = 0.0001), translated in a survival advantage of L-GEM treated animals versus other groups. Pharmacokinetic studies showed enhancement of systemic bioavailability of L-GEM (t (1/2) = 8 h) versus to GEM (t (1/2) = 1.5 h). Our findings demonstrate that L-GEM is an effective agent against PC and exerts higher antitumor activity as compared to free GEM with no appreciable increase in toxicity. These results provide the pre-clinical rational for L-GEM clinical development for the treatment of PC patients.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/uso terapêutico , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Antimetabólitos Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacocinética , Desoxicitidina/uso terapêutico , Portadores de Fármacos , Meia-Vida , Humanos , Lipossomos , Camundongos , Camundongos SCID , Microscopia Confocal , Polietilenoglicóis/química , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
16.
Behav Brain Res ; 190(1): 22-32, 2008 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-18355933

RESUMO

The aim of present work was the evaluation of the effects on brain levels of nerve growth factor (NGF) and of its high-affinity tyrosine kinase A receptor (TrkA), induced in rats unilaterally lesioned at nucleus basalis magnocellularis (NBM), by treatment with choline pivaloyl ester (CPE). CPE was daily administered (60 micromol/Kg ip) during 3 weeks to rats selectively lesioned by AMPA infusion into right NBM; the intact left NBM serving as control. NGF levels were determined in cerebral cortex and hippocampus by Elisa assay. TrkA receptor expression was evaluated in right NBM by Western blotting analysis. CPE treatment significantly increased NGF levels in both hippocampus and neocortex in right NBM, compared with intact left counter-part and controls. Western blotting showed an evident enhancement in TrkA receptor expression in lesioned right NBM in comparison with intact left counter-part and controls. CPE treatment was also able to restore, in bilaterally NBM-lesioned rats, the disrupted cortical EEG and HVS activities as well as to reverse deficits in learning and memory in spatial navigation and probe trials, and cognitive capacities in object recognition task.


Assuntos
Encéfalo/metabolismo , Transtornos Cognitivos/tratamento farmacológico , Ciclopentanos/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Fator de Crescimento Neural/metabolismo , Receptor trkA/metabolismo , Animais , Núcleo Basal de Meynert/efeitos dos fármacos , Núcleo Basal de Meynert/patologia , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Colina O-Acetiltransferase/metabolismo , Transtornos Cognitivos/etiologia , Eletroencefalografia , Lateralidade Funcional , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/etiologia , Fator de Crescimento Neural/genética , Testes Neuropsicológicos , Síndromes Neurotóxicas/complicações , Síndromes Neurotóxicas/patologia , Ratos , Ratos Wistar , Tempo de Reação/efeitos dos fármacos , Receptor trkA/genética , Fatores de Tempo
17.
Graefes Arch Clin Exp Ophthalmol ; 246(1): 121-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17479276

RESUMO

BACKGROUND: In vitro and in vivo studies demonstrated the antiviral efficacy of nerve growth factor (NGF) and its cyto-protective effect in herpes simplex virus (HSV)-infected cells. The aims of this study were to evaluate the role of endogenous NGF in HSV corneal infection, and the effects of topical NGF treatment on herpetic keratitis. METHODS: Herpetic keratitis was induced in 40 rabbits with the HSV-1 McKrae strain. Animals were divided into four groups, and treated with topical neutralizing anti-NGF antibodies, NGF, acyclovir or balanced salt solution (BSS) respectively. The clinical course of HSV keratitis was evaluated and scored by slit-lamp examination. In addition, biochemical (immunohistochemistry for glycoprotein D) and molecular (nested PCR for glycoprotein D) analyses were carried out to estimate viral replication. RESULTS: Treatment with anti-NGF antibodies induced a more severe keratitis associated with increased biochemical and molecular markers of active viral replication. Two animals in this group developed lethal HSV encephalitis. Conversely, topical treatment with NGF induced a significant amelioration of clinical and laboratory parameters when compared to the BSS treated group (control). No significant differences were observed between NGF- and acyclovir-treated groups. CONCLUSIONS: This study demonstrated the crucial role of endogenous NGF in herpetic keratitis. The comparable effects of NGF and acyclovir confirm the antiviral activity of NGF, and indicate a potential use of topical NGF in herpetic keratitis.


Assuntos
Modelos Animais de Doenças , Ceratite Herpética/tratamento farmacológico , Fator de Crescimento Neural/uso terapêutico , Aciclovir/uso terapêutico , Administração Tópica , Animais , Anticorpos Bloqueadores/uso terapêutico , Antivirais/uso terapêutico , Citoproteção , Feminino , Herpesvirus Humano 1/fisiologia , Técnicas Imunoenzimáticas , Ceratite Herpética/metabolismo , Fator de Crescimento Neural/fisiologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , Coelhos , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Replicação Viral
18.
BMC Neurosci ; 8: 106, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-18062818

RESUMO

BACKGROUND: HIV envelope gp 120 glycoprotein is released during active HIV infection of brain macrophages thereby generating inflammation and oxidative stress which contribute to the development of the AIDS-Dementia Complex (ADC). Gp120 has also been found capable to generate excitotoxic effect on brain tissue via enhancement of glutamatergic neurotransmission, leading to neuronal and astroglial damage, though the mechanism is still to be better understood. Here we investigated on the effect of N-acetylcysteine (NAC), on gp120-induced damage in human cultured astroglial cells and the possible contribution of gp120-related reacting oxygen species (ROS) in the imbalanced activity of glutamine synthase (GS), the enzyme that metabolizes glutamate into glutamine within astroglial cells playing a neuroprotective role in brain disorders. RESULTS: Incubation of Lipari human cultured astroglial cells with gp 120 (0.1-10 nM) produced a significant reduction of astroglial cell viability and apoptosis as evaluated by TUNEL reaction and flow cytometric analysis (FACS). This effect was accompanied by lipid peroxidation as detected by means of malondialdehyde assay (MDA). In addition, gp 120 reduced both glutamine concentration in astroglial cell supernatants and GS expression as detected by immunocytochemistry and western blotting analysis. Pre-treatment of cells with NAC (0.5-5 mM), dose-dependently antagonised astroglial apoptotic cell death induced by gp 120, an effect accompanied by significant attenuation of MDA accumulation. Furthermore, both effects were closely associated with a significant recovery of glutamine levels in cell supernatants and by GS expression, thus suggesting that overproduction of free radicals might contribute in gp 120-related dysfunction of GS in astroglial cells. CONCLUSION: In conclusion, the present experiments demonstrate that gp 120 is toxic to astroglial cells, an effect accompanied by lipid peroxidation and by altered glutamine release. All the effects of gp120 on astroglial cells were counteracted by NAC thus suggesting a novel and potentially useful approach in the treatment of glutammatergic disorders found in HAD patients.


Assuntos
Acetilcisteína/farmacologia , Astrócitos/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Glutamato-Amônia Ligase/fisiologia , Proteína gp120 do Envelope de HIV/toxicidade , Análise de Variância , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Interações Medicamentosas , Citometria de Fluxo , Glutamina/metabolismo , Humanos , Marcação In Situ das Extremidades Cortadas/métodos , Masculino , Malondialdeído/metabolismo , Pessoa de Meia-Idade
19.
J Mol Med (Berl) ; 85(7): 707-21, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17571248

RESUMO

The interleukin-2 is a cytokine that is essential for lymphocytic survival and function. Ectopic expression of the IL-2 receptor in epithelial tissues has been reported previously, although the functional significance of this expression is still being investigated. We provided novel structural and functional information on the expression of the IL-2 receptor in kidney cancer cells and in other normal and neoplastic human epithelial tissues. In A-498 kidney cancer cells, we showed that IL-2 binding to its own receptor triggers a signal transduction pathway leading to the inhibition of proliferation and apoptosis. We found that the inhibition of proliferation is associated with Erk1/2 dephosphorylation, whereas the survival signals appear to be mediated by Sgk1 activation. This investigation focuses on the IL-2 induced regulation of Sgk1 and describes a role of the IL-2 receptor and Sgk1 in the regulation of epithelial tumor cell death and survival.


Assuntos
Apoptose , Proliferação de Células , Proteínas Imediatamente Precoces/fisiologia , Interleucina-2/fisiologia , Neoplasias Renais/patologia , Proteínas Serina-Treonina Quinases/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação da Expressão Gênica , Humanos , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Neoplasias Renais/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Interleucina-2/análise , Transdução de Sinais
20.
Neurochem Int ; 50(1): 130-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16963163

RESUMO

In our previous studies, we demonstrated that intraperitoneal (i.p.) injections with the neurotransmitter/neuromodulatory peptide Cholecystokinin-8 (CCK-8) stimulate the synthesis of the neurotrophin nerve growth factor (NGF) resulting in the structural and functional recovery of neuronal damage. This neurotrophin-mediated neuroprotective action of CCK-8 has opened a new perspective for a better understanding of the CCK neurobiological and pharmacological properties. To explore the possible beneficial effects of the CCK-induced increase of neurotrophin availability in brain, we compared the effects of i.p. CCK-8 in healthy rats and in a chemical kindling model using a subconvulsive dose of pentylenetetrazol (PTZ). Behavioural changes were monitored during treatment and classified according to a six-point scale. After 3 weeks of treatment (12 trials), the PTZ group of rats manifested generalized clonic-tonic seizures (Class 5 behaviour). For this reason, this time point was chosen to compare the effects of CCK-8 treatment on the expression of NGF, the brain derived neurotrophin factor (BDNF) and their receptors in the septum and hippocampus. We found that repeated i.p. injections with CCK-8 in adult rats result in: (1) an increase of NGF and BDNF protein and mRNA levels in the septum and hippocampus; (2) a down-regulation of TrkA and p75NTR and an up-regulation of TrkB; (3) reduced susceptibility to develop chemical kindling; (4) recovery of the PTZ-induced changes in the expression of neurotrophin receptors in the septal and hippocampal tissues. This data clearly indicates that CCK-induced variation of neurotrophin synthesis in brain is able to influence the susceptibility to develop seizures in adult rats most probably by counteracting the progressive neuronal dysfunction and/or damage.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/biossíntese , Colecistocinina/farmacologia , Hipocampo/efeitos dos fármacos , Excitação Neurológica , Fator de Crescimento Neural/biossíntese , Fragmentos de Peptídeos/farmacologia , Receptor trkA/metabolismo , Receptor trkB/metabolismo , Animais , Sequência de Bases , Comportamento Animal/efeitos dos fármacos , Primers do DNA , Hipocampo/metabolismo , Hipocampo/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley
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