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1.
Food Chem ; 305: 125484, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514048

RESUMO

Grape pathogenesis-related proteins can cause haze in wine that is undesirable for consumers. Bentonite is used to remove these proteins but is a non-renewable natural material and reduces wine volume due to poor settling. As a potential bentonite alternative, grape seeds powder (GSP) was added to four wines and two grape juice varieties. Addition to wine required high doses (25-32 g/L) for protein removal and haze prevention and this induced changes to wine composition. By contrast, addition to grape juice prior to fermentation required substantially lower doses of GSP (5 g/L) to prevent haze formation. Further 20 g/L of GSP added to the must induced less changes to wine composition than direct addition of GSP to the wine. No changes were recorded in the efficacy of protein removal by changing the GSP source (red or white grape marc), or by using grape seed roasting. Despite the need for additional trials, these preliminary results suggest that GSP may be considered as a viable alternative to bentonite especially when added to juice prior to fermentation.

2.
Food Chem ; 288: 78-85, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30902317

RESUMO

Oxidative spoilage is a phenomenon that can occur both in winemaking and during bottle storage. The complexity of oxidative spoilage makes it difficult to identify all the products from oxidation processes, especially in bottled wines with varying degrees of oxidative spoilage, i.e., "random oxidation". To this end, this study sought to obtain a deeper insight into the chemistry of white wine samples to identify compounds able to discriminate the different oxidative statuses. The results of metabolomics and VIP analysis outlined molecules such as 3-methylcatechol, cyanidin 3-O-6″-p-coumaroyl-glucoside, delphinidin 3-O-glucoside, quercetin 3-O-glucosyl-xyloside, dihydroquercetin, and quercetin 3-O-glucuronide to be discriminant in the detection of the oxidative status of the white wines under study, which were preliminarily classified in low and high oxidation classes by means of sensory analysis. Parameters such as total and free sulfur dioxide content and browning and pinking measurements were confirmed to remain significantly correlated with oxidation-related issues.


Assuntos
Metabolômica , Fenóis/análise , Vinho/análise , Antocianinas/análise , Cromatografia Líquida de Alta Pressão , Análise Discriminante , Glucosídeos/análise , Análise dos Mínimos Quadrados , Oxirredução , Fenóis/química , Espectrometria de Massas por Ionização por Electrospray , Dióxido de Enxofre/análise
3.
Stem Cell Reports ; 2018 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-30416049

RESUMO

We generated patient-specific disease-free induced pluripotent stem cells (iPSCs) from peripheral blood CD34+ cells and differentiated them into functional endothelial cells (ECs) secreting factor VIII (FVIII) for gene and cell therapy approaches to cure hemophilia A (HA), an X-linked bleeding disorder caused by F8 mutations. iPSCs were transduced with a lentiviral vector carrying FVIII transgene driven by an endothelial-specific promoter (VEC) and differentiated into bona fide ECs using an optimized protocol. FVIII-expressing ECs were intraportally transplanted in monocrotaline-conditioned non-obese diabetic (NOD) severe combined immune-deficient (scid)-IL2rγ null HA mice generating a chimeric liver with functional human ECs. Transplanted cells engrafted and proliferated in the liver along sinusoids, in the long term showed stable therapeutic FVIII activity (6%). These results demonstrate that the hemophilic phenotype can be rescued by transplantation of ECs derived from HA FVIII-corrected iPSCs, confirming the feasibility of cell-reprogramming strategy in patient-derived cells as an approach for HA gene and cell therapy.

4.
Langmuir ; 34(45): 13713-13724, 2018 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-30394747

RESUMO

New biomimetic magnetite nanoparticles (hereafter BMNPs) with sizes larger than most common superparamagnetic nanoparticles were produced in the presence of the recombinant MamC protein from Magnetococcus marinus MC-1 and functionalized with doxorubicin (DOXO) intended as potential drug nanocarriers. Unlike inorganic magnetite nanoparticles, in BMNPs the MamC protein controls their size and morphology, providing them with magnetic properties consistent with a large magnetic moment per particle; moreover, it provides the nanoparticles with novel surface properties. BMNPs display the isoelectric point at pH 4.4, being strongly negatively charged at physiological pH (pH 7.4). This allows both (i) their functionalization with DOXO, which is positively charged at pH 7.4, and (ii) the stability of the DOXO-surface bond and DOXO release to be pH dependent and governed by electrostatic interactions. DOXO adsorption follows a Langmuir-Freundlich model, and the coupling of DOXO to BMNPs (binary biomimetic nanoparticles) is very stable at physiological pH (maximum release of 5% of the drug adsorbed). Conversely, when pH decreases, these electrostatic interactions weaken, and at pH 5, DOXO is released up to ∼35% of the amount initially adsorbed. The DOXO-BMNPs display cytotoxicity on the GTL-16 human gastric carcinoma cell line in a dose-dependent manner, reaching about ∼70% of mortality at the maximum amount tested, while the nonloaded BMNPs are fully cytocompatible. The present data suggest that BMNPs could be useful as potential drug nanocarriers with a drug adsorption-release governed by changes in local pH values.

5.
PLoS One ; 13(6): e0199371, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29920561

RESUMO

BACKGROUND: Improving the knowledge of angiomyolipoma physiopathology might help in refining its pharmacological treatment. We investigated if angiomyolipoma cells have migratory properties, how their growth and motility can be influenced by the hormonal milieu, and if this can be related to a specific gender. METHODS: Primary cells were isolated from angiomyolipomas surgically resected for therapeutical reasons in a female and in a male patient. The genetic control demonstrated no TSC2 deletion. Bi- (wound healing) and three-dimensional (transwell assay) migration were analyzed in vitro in basal conditions and under the influence of 17- ß-estradiol and SDF-1α. RESULTS: Treatment up to 72 hours with 17-ß-estradiol (0.1-100 nM), tamoxifen (0.2-20 µM) or with both, does not modify angiomyolipoma cells proliferation. On the other hand, SDF-1α and 17-ß-estradiol treatment induce a significant motility increase (both bi- and three-dimensional) which becomes evident already after 2 hours of incubation. Angiomyolipoma cells express mRNA coding for SDF-1α and 17-ß-estradiol receptors and secrete both the metalloproteases principally involved in malignant phenotype acquisition, i.e. MMP-2 and MMP-9. CONCLUSION: Angiomyolipoma cells behave similarly, despite their different source. Primary angiomyolipoma cells migrate in response to hormonal milieu and soluble factors, and produce active metalloproteases, both aspects being consistent with the theory claiming they can migrate to the lungs (and/or other organs) and colonizing them. No main feature, among the aspects we analyzed, seems to be referable to the gender of origin.

6.
Food Chem ; 264: 301-309, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29853380

RESUMO

This investigation focuses on the use of chitosan treatment simulating a bentonite fining in order to detect any modification of the wine haze potential by simultaneously evaluating the secondary effects on untargeted fixed and volatile compounds. A significant removal of chitinases was observed after fining an aromatic white wine with 1 g/L of a fungoid chitosan. Even if the more stable thaumatin like protein fractions were not significantly affected, the heat stability of the fined chitosan wine samples were highly improved in the 55-62 °C range. Among the secondary effects of a fining treatment, a reduction of tartaric acid, malic acid, potassium and iron was showed. All the free terpenols with the exception of α-terpineol were reduced in significant amounts, whilst the glycosylated forms and the fermentative aroma compounds were not affected by a 1 g/L chitosan addition.

7.
Curr Cancer Drug Targets ; 18(8): 816-828, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28669341

RESUMO

BACKGROUND: Malignant Pleural Mesothelioma (MPM) is an asbestos-associated tumor with poor prognosis and few therapeutic options. JQ1, a selective antagonist of BRD4, modulates transcription of oncogenes, including MPM chemoresistance-associated c-Myc and Fra-1. OBJECTIVE: We investigated if JQ1 could enhance the efficacy of cisplatin against MPM. METHODS: The antiproliferative activity of cisplatin in combination with JQ1 was assessed on MPM cell lines representative of the cellular phenotypes of this tumor (epithelioid, sarcomatoid and biphasic), and on one cisplatin resistant sub-line. The combination schedule was optimized adopting a 3Dspheroid model. Drug combination effects were correlated with cell cycle distribution and senescence- associated ß-galactosidase positive cells. The expression of c-Myc and Fra-1 proteins and some apoptosis markers was assessed by immunoblotting and RT-qPCR. DNA damage and repair were evaluated by means of alkaline comet assay. RESULTS: JQ1 in combination with cisplatin elicited additive or synergistic (superadditive) antiproliferative effects on MPM cells, depending on the cell line. The combination showed tumor regression on the 3D-spheroid model. It induced increased apoptosis, along with decreased c-Myc and, sometimes, Fra-1 expression. JQ1 decreased cisplatin-induced DNA breaks in all MPM cells and increased senescence even in less proficient cells, thus enhancing the DNA Damage Response (DDR). CONCLUSION: The superadditive effect is due to c-Myc repression. The consequent DDR enhancement triggers to apoptosis induction and/or permanent growth arrest (senescence), depending on the MPM cellular context, leading to tumor regression. Thus, the pharmacological modulation of BET activity could represent a promising tool for future MPM therapy.

8.
Chemistry ; 23(55): 13784-13791, 2017 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-28752941

RESUMO

Physicochemical methods have been used to investigate interactions occurring in solution between the dicarbene gold(I) complex [Au(9-methylcaffein-8-ylidene)2 ]BF4 (AuNHC) and a human telomeric DNA sequence, namely Tel23. Circular dichroism measurements allow identification of the conformational changes experienced by Tel23 upon interaction with AuNHC, and the respective binding stoichiometries and constants were determined. Computational studies provide a good link between previous crystallographic results of the same system and the present solution data, offering an exhaustive description of the inherent noncovalent metallodrug-DNA interactions. Remarkably, we found that a preformed AuNHC/Tel23 adduct is capable of producing strong and selective inhibition of the enzyme telomerase. The latter feature is mechanistically relevant and might account for the conspicuous in vitro anticancer properties of the investigated dicarbene gold(I) complex.


Assuntos
Complexos de Coordenação/metabolismo , Ouro/química , Telômero/metabolismo , Sequência de Bases , Sítios de Ligação , Dicroísmo Circular , Complexos de Coordenação/química , Adutos de DNA/química , Humanos , Simulação de Dinâmica Molecular , Conformação de Ácido Nucleico , Telomerase/antagonistas & inibidores , Telomerase/metabolismo , Telômero/química
10.
PLoS One ; 10(9): e0137999, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26375957

RESUMO

A major obstacle to an effective myocardium stem cell therapy has always been the delivery and survival of implanted stem cells in the heart. Better engraftment can be achieved if cells are administered as cell aggregates, which maintain their extra-cellular matrix (ECM). We have generated spheroid aggregates in less than 24 h by seeding human cardiac progenitor cells (hCPCs) onto methylcellulose hydrogel-coated microwells. Cells within spheroids maintained the expression of stemness/mesenchymal and ECM markers, growth factors and their cognate receptors, cardiac commitment factors, and metalloproteases, as detected by immunofluorescence, q-RT-PCR and immunoarray, and expressed a higher, but regulated, telomerase activity. Compared to cells in monolayers, 3D spheroids secreted also bFGF and showed MMP2 activity. When spheroids were seeded on culture plates, the cells quickly migrated, displaying an increased wound healing ability with or without pharmacological modulation, and reached confluence at a higher rate than cells from conventional monolayers. When spheroids were injected in the heart wall of healthy mice, some cells migrated from the spheroids, engrafted, and remained detectable for at least 1 week after transplantation, while, when the same amount of cells was injected as suspension, no cells were detectable three days after injection. Cells from spheroids displayed the same engraftment capability when they were injected in cardiotoxin-injured myocardium. Our study shows that spherical in vivo ready-to-implant scaffold-less aggregates of hCPCs able to engraft also in the hostile environment of an injured myocardium can be produced with an economic, easy and fast protocol.


Assuntos
Coração/fisiologia , Miocárdio/citologia , Esferoides Celulares/citologia , Esferoides Celulares/transplante , Transplante de Células-Tronco , Células-Tronco/citologia , Engenharia Tecidual , Idoso , Idoso de 80 Anos ou mais , Animais , Western Blotting , Diferenciação Celular , Movimento Celular , Proliferação de Células , Células Cultivadas , Feminino , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Miocárdio/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esferoides Celulares/metabolismo , Células-Tronco/metabolismo , Tecidos Suporte
11.
Langmuir ; 31(5): 1766-75, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25602940

RESUMO

Multifunctional biomimetic nanoparticles (NPs) are acquiring increasing interest as carriers in medicine and basic research since they can efficiently combine labels for subsequent tracking, moieties for specific cell targeting, and bioactive molecules, e.g., drugs. In particular, because of their easy synthesis, low cost, good biocompatibility, high resorbability, easy surface functionalization, and pH-dependent solubility, nanocrystalline apatites are promising candidates as nanocarriers. This work describes the synthesis and characterization of bioinspired apatite nanoparticles to be used as fluorescent nanocarriers targeted against the Met/hepatocyte growth factor receptor, which is considered a tumor associated cell surface marker of many cancers. To this aim the nanoparticles have been labeled with Fluorescein-5-isothiocyanate (FITC) by simple isothermal adsorption, in the absence of organic, possibly toxic, molecules, and then functionalized with a monoclonal antibody (mAb) directed against such a receptor. Direct labeling of the nanoparticles allowed tracking the moieties with spatiotemporal resolution and thus following their interaction with cells, expressing or not the targeted receptor, as well as their fate in vitro. Cytofluorometry and confocal microscopy experiments showed that the functionalized nanocarriers, which emitted a strong fluorescent signal, were rapidly and specifically internalized in cells expressing the receptor. Indeed, we found that, once inside the cells expressing the receptor, mAb-functionalized FITC nanoparticles partially dissociated in their two components, with some mAbs being recycled to the cell surface and the FITC-labeled nanoparticles remaining in the cytosol. This work thus shows that FITC-labeled nanoapatites are very promising probes for targeted cell imaging applications.


Assuntos
Anticorpos Monoclonais/química , Apatitas/química , Materiais Biomiméticos/química , Fluoresceína-5-Isotiocianato/química , Corantes Fluorescentes/química , Imagem Molecular/métodos , Nanopartículas/química , Anticorpos Monoclonais/imunologia , Transporte Biológico , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/metabolismo , Linhagem Celular Tumoral , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/metabolismo , Humanos , Espaço Intracelular/metabolismo , Teste de Materiais , Proteínas Proto-Oncogênicas c-met/imunologia
12.
Food Funct ; 5(10): 2542-51, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25133994

RESUMO

Cocoa contains phenolic compounds with known antioxidant and antiradical properties beneficial in different pathologies, including cardiovascular diseases. Herein, we have evaluated the protective effects of clovamide, a minor cocoa component, against oxidative stress induced in the rat cardiomyoblast cell line, also comparing it to its bio-isosteric form, rosmarinic acid, and to the main monomeric flavan-3-ol from low-molecular-weight polyphenol in cocoa, i.e. epicatechin. At nano-micro-molar concentrations, the three compounds inhibited the production of reactive oxygen species and apoptosis, evaluated under different aspects, namely, annexin V positivity, DNA fragmentation, caspase release and activation. These molecules can, thus, be considered for their bioactive beneficial activity in the context of cardiovascular pathologies and, particularly, in the protection towards oxidative stress that follows ischemic injury. Clovamide may, thus, be the primary compound for the development of innovative nutraceutical strategies towards cardiovascular diseases.


Assuntos
Peróxido de Hidrogênio/efeitos adversos , Mioblastos Cardíacos/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Tirosina/análogos & derivados , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Cacau/química , Linhagem Celular , Cinamatos/farmacologia , Fragmentação do DNA/efeitos dos fármacos , Depsídeos/farmacologia , Flavonoides/farmacologia , Mioblastos Cardíacos/citologia , Mioblastos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Tirosina/farmacologia
13.
J Inorg Biochem ; 140: 219-27, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25171667

RESUMO

The biological properties of a series of cisplatin-based Pt(IV) prodrug candidates, namely trans,cis,cis-[Pt(carboxylato)2Cl2(NH3)2], where carboxylato=CH3(CH2)nCOO(-) [(1), n=0; (2), n=2; (3), n=4; (4), n=6] having a large interval of lipophilicity are discussed. The stability of the complexes was tested in different pH conditions (i.e. from 1.0 to 9.0) to simulate the hypothetical conditions for an oral route of administration, showing a high stability (>90%). The transformation into their active Pt(II) metabolites was demonstrated in the presence of ascorbic acid, with a pseudo-first order kinetics, the half-time of which smoothly decreases as the chain length of carboxylic acid increases. Their antiproliferative activity has been evaluated in vitro on a large panel of human cancer cell lines. As expected, the potency increases with the chain length: 3 and 4 resulted by far more active than cisplatin on all cell lines of about one or two orders of magnitude, respectively. Both complexes retained their activity also on cisplatin-resistant cell line, and exhibited a progressive increase of the selectivity compared with non-tumor cells. These results were confirmed with more prolonged treatment (up to 14days) studied on multicellular tumor spheroids (MCTSs). In this case the Pt(IV) complexes exert a protracted antiproliferative action, even if the drug is removed from the culture medium. Finally, in a time-course experiment of the total platinum evaluation in mice blood (after a single oral administration of the title complexes), 2 gave the best results, representing a good compromise between lipophilicity and water solubility, that increase and decrease respectively on passing from 1 to 4.


Assuntos
Antineoplásicos/farmacologia , Compostos de Platina/farmacologia , Pró-Fármacos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Humanos , Oxirredução , Compostos de Platina/química , Compostos de Platina/farmacocinética , Pró-Fármacos/química , Pró-Fármacos/farmacocinética
14.
Stem Cells Dev ; 23(8): 888-98, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24328510

RESUMO

Electrical stimulation (ES) of cells has been shown to induce a variety of responses, such as cytoskeleton rearrangements, migration, proliferation, and differentiation. In this study, we have investigated whether monophasic and biphasic pulsed ES could exert any effect on the proliferation and differentiation of human cardiac progenitor cells (hCPCs) isolated from human heart fragments. Cells were cultured under continuous exposure to monophasic or biphasic ES with fixed cycles for 1 or 3 days. Results indicate that neither stimulation protocol affected cell viability, while the cell shape became more elongated and reoriented more perpendicular to the electric field direction. Moreover, the biphasic ES clearly induced the upregulation of early cardiac transcription factors, MEF2D, GATA-4, and Nkx2.5, as well as the de novo expression of the late cardiac sarcomeric proteins, troponin T, cardiac alpha actinin, and SERCA 2a. Both treatments increased the expression of connexin 43 and its relocation to the cell membrane, but biphasic ES was faster and more effective. Finally, when hCPCs were exposed to both monophasic and biphasic ES, they expressed de novo the mRNA of the voltage-dependent calcium channel Cav 3.1(α1G) subunit, which is peculiar of the developing heart. Taken together, these results show that ES alone is able to set the conditions for early differentiation of adult hCPCs toward a cardiac phenotype.


Assuntos
Células-Tronco Adultas/fisiologia , Diferenciação Celular , Biomarcadores/metabolismo , Proliferação de Células , Forma Celular , Sobrevivência Celular , Células Cultivadas , Estimulação Elétrica , Expressão Gênica , Regulação da Expressão Gênica , Átrios do Coração/citologia , Humanos
15.
Langmuir ; 29(26): 8213-21, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23735159

RESUMO

In this work, the efficiency of bioinspired citrate-functionalized nanocrystalline apatites as nanocarriers for delivery of doxorubicin (DOXO) has been assessed. The nanoparticles were synthesized by thermal decomplexing of metastable calcium/citrate/phosphate solutions both in the absence (Ap) and in the presence (cAp) of carbonate ions. The presence of citrate and carbonate ions in the solution allowed us to tailor the size, shape, carbonate content, and surface chemistry of the nanoparticles. The drug-loading efficiency of the two types of apatite was evaluated by means of the adsorption isotherms, which were found to fit a Langmuir-Freundlich behavior. A model describing the interaction between apatite surface and DOXO is proposed from adsorption isotherms and ζ-potential measurements. DOXO is adsorbed as a dimer by means of a positively charged amino group that electrostatically interacts with negatively charged surface groups of nanoparticles. The drug-release profiles were explored at pHs 7.4 and 5.0, mimicking the physiological pH in the blood circulation and the more acidic pH in the endosome-lysosome intracellular compartment, respectively. After 7 days at pH 7.4, cAp-DOXO released around 42% less drug than Ap-DOXO. However, at acidic pH, both nanoassemblies released similar amounts of DOXO. In vitro assays analyzed by confocal microscopy showed that both drug-loaded apatites were internalized within GTL-16 human carcinoma cells and could release DOXO, which accumulated in the nucleus in short times and exerted cytotoxic activity with the same efficiency. cAp are thus expected to be a more promising nanocarrier for experiments in vivo, in situations where intravenous injection of nanoparticles are required to reach the targeted tumor, after circulating in the bloodstream.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Apatitas/química , Citrato de Cálcio/química , Carbonatos/química , Doxorrubicina/administração & dosagem , Portadores de Fármacos , Nanopartículas/química , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Composição de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Eletricidade Estática , Termodinâmica
16.
Stem Cells Dev ; 22(21): 2873-84, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23777308

RESUMO

The emerging field of tissue engineering and regenerative medicine is a multidisciplinary science that is based on the combination of a reliable source of stem cells, biomaterial scaffolds, and cytokine growth factors. Adult mesenchymal stem cells are considered important cells for applications in this field, and adipose tissue has revealed to be an excellent source of them. Indeed, adipose-derived stem cells (ASCs) can be easily isolated from the stromal vascular fraction (SVF) of adipose tissue. During the isolation and propagation of murine ASCs, we observed the appearance of a spontaneously immortalized cell clone, named m17.ASC. This clone has been propagated for more than 180 passages and stably expresses a variety of stemness markers, such as Sca-1, c-kit/CD117, CD44, CD106, islet-1, nestin, and nucleostemin. Furthermore, these cells can be induced to differentiate toward osteogenic, chondrogenic, adipogenic, and cardiogenic phenotypes. m17.ASC clone displays a normal karyotype and stable telomeres; it neither proliferates when plated in soft agar nor gives rise to tumors when injected subcutaneously in NOD/SCID-γ (null) mice. The analysis of gene expression highlighted transcriptional traits of SVF cells. m17.ASCs were genetically modified by lentiviral vectors carrying green fluorescent protein (GFP) as a marker transgene and efficiently engrafted in the liver, when injected in the spleen of NOD/SCID-γ (null) monocrotaline-treated mice. These results suggest that this non-tumorigenic spontaneously immortalized ASC line may represent a useful tool (cell model) for studying the differentiation mechanisms involved in tissue repair as well as a model for pharmacological/toxicological studies.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Multipotentes/citologia , Gordura Subcutânea/citologia , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Antígenos Ly/genética , Antígenos Ly/metabolismo , Diferenciação Celular/genética , Linhagem Celular , Condrócitos/citologia , Condrócitos/metabolismo , Células Clonais/citologia , Células Clonais/metabolismo , Células Clonais/transplante , Perfilação da Expressão Gênica , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Subunidade gama Comum de Receptores de Interleucina/deficiência , Subunidade gama Comum de Receptores de Interleucina/genética , Cariótipo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Microscopia Confocal , Células-Tronco Multipotentes/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Osteócitos/citologia , Osteócitos/metabolismo , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Eur J Med Chem ; 63: 387-400, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23517728

RESUMO

The design, modeling, synthesis and biological activity evaluation of two hybrid agents formed by 7-oxyiminomethylcamptothecin derivatives and diaminedichloro-platinum (II) complex are reported. The compounds showed growth inhibitory activity against a panel of human tumor cell lines, including sublines resistant to topotecan and platinum compounds. The derivatives were active in all the tested cell lines, and compound 1b, the most active one, was able to overcome cisplatin resistance in the osteosarcoma U2OS/Pt cell line. Platinum-containing camptothecins produced platinum-DNA adducts and topoisomerase I-mediated DNA damage with cleavage pattern and persistence similar to SN38, the active principle of irinotecan. Compound 1b exhibited an appreciable antitumor activity in vivo against human H460 tumor xenograft, comparable to that of irinotecan at lower well-tolerated dose levels and superior to cisplatin. The results support the interpretation that the diaminedichloro-platinum (II) complex conjugated via an oxyiminomethyl linker at the 7-position of the camptothecin resulted in a new class of effective antitumor compounds.


Assuntos
Antineoplásicos/síntese química , Camptotecina/química , Compostos Organoplatínicos/síntese química , Platina/química , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , DNA Topoisomerases Tipo I/química , DNA Topoisomerases Tipo I/metabolismo , Desenho de Drogas , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Concentração Inibidora 50 , Camundongos , Camundongos Nus , Modelos Químicos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Compostos Organoplatínicos/metabolismo , Compostos Organoplatínicos/farmacologia , Ligação Proteica , Estrutura Terciária de Proteína , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Biochem Pharmacol ; 79(8): 1108-17, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20005867

RESUMO

Pt compounds still represent the mainstay of the treatment of ovarian carcinoma. The aim of the present study was to investigate the molecular bases of resistance to Pt drugs using an oxaliplatin-resistant ovarian carcinoma cell model IGROV-1/OHP. These cells exhibited high levels of resistance to oxaliplatin, cross-resistance to cisplatin and topotecan and displayed a marked accumulation defect of Pt drugs. This feature was associated with increased expression and altered N-linked glycosylation of ATP binding cassette transporters MRP1 and MRP4. Pre-treatment with tunicamycin, which inhibits the biosynthesis of N-linked oligosaccharides, decreased the accumulation of Pt in sensitive cells exposed to oxaliplatin or cisplatin and increased the electrophoretic mobility of MRP1 and MRP4, reproducing the association between decreased glycosylation of MRP1 and MRP4 and decreased Pt accumulation observed in the resistant IGROV-1/OHP cells. The observed N-glycosylation defect of oxaliplatin-resistant cells was linked to reduced levels of N-acetylglucosamine-1-phosphotransferase (GNPTG) and mannosyl (alpha-1,6-)-glycoprotein beta-1,6-N-acetyl-glucosaminyltransferase (MGAT5). This feature, observed in IGROV-1/OHP cells, was associated with decreased retention of Pt drugs. In addition, the overexpression of fully glycosylated MRP1 or MRP4 in tumor cell line of ovarian origin was associated with resistance to oxaliplatin and cisplatin. Our findings, showing that development of resistance to oxaliplatin results in up-regulation of MRPs, support that patients with oxaliplatin-refractory ovarian carcinomas may benefit from non-Pt-based regimens which do not contain MRP1 and MRP4 substrates.


Assuntos
Antineoplásicos/farmacologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Compostos Organoplatínicos/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Western Blotting , Linhagem Celular Tumoral , Cisplatino/farmacocinética , Resistencia a Medicamentos Antineoplásicos , Feminino , Glicosilação , Glicosiltransferases/análise , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/análise , Compostos Organoplatínicos/farmacocinética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Oxaliplatina , Tunicamicina/farmacologia
19.
J Inorg Biochem ; 102(4): 629-35, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18037490

RESUMO

Cellular uptake of a drug is one of the most important factors influencing its pharmacodynamics and pharmacokinetics. Our laboratory has previously studied platinum uptake following cisplatin, carboplatin and oxaliplatin treatment at sub-lethal doses of selected tumour cell lines. Here we report on the influence of temperature on dose-dependent antiproliferative effects, cellular uptake and DNA platination of these platinum-based drugs tested on MCF-7 human mammary carcinoma cell line. Inductively coupled plasma-mass spectrometry (ICP-MS) technique has been chosen to perform Pt determinations on cells treated with drug concentrations similar with those usually found in vivo in human plasma. The high sensitivity and analytical rapidity of this technique made possible to carry out a very large amount of Pt determinations (about 300) necessary for this study. Hyperthermia (43 degrees C) proved a synergistic effect with cisplatin on cell growth inhibition, while only an additive effect was demonstrated for carboplatin and oxaliplatin. This behaviour might be explained by the higher DNA platination ratio between data at 43 and 37 degrees C of cisplatin with respect to those of carboplatin and oxaliplatin.


Assuntos
Proliferação de Células/efeitos dos fármacos , DNA/efeitos dos fármacos , Compostos de Platina/farmacologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Espectrometria de Massas , Compostos de Platina/metabolismo , Temperatura Ambiente
20.
Curr Med Chem ; 12(26): 3091-102, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16375703

RESUMO

Telomerase is a ribonucleoprotein polymerase that maintains the length of telomeric DNA by adding hexameric units (TTAGGG) to the ends of the chromosomes. This mechanism prevents replicative senescence, thus conferring unlimited proliferative potential to cells. Telomerase reactivation has been detected in most human tumour tissue, indicating that the enzyme may be useful as a specific tumour marker. The inhibition of telomerase causes a progressive and critical reduction of telomeres, leading to a potent signal for the blockage of cell proliferation and the induction of apoptosis. Since normal somatic cells lack telomerase activity, the anti-telomerase approach is highly specific for tumour cells and metastases. Prolonged treatment is required before enzyme deactivation causes the telomeres to be shortened enough to induce senescence and apoptosis. Therefore, the drugs employed in anti-telomerase therapy should be of only moderate non-specific cytotoxicity. Certain cis-Pt(II)-complexes have recently been shown to be effective inhibitors of telomerase in both cell-free and in vitro assays, most likely by targeting the nucleobases of the RNA component of the enzyme.


Assuntos
Neoplasias/tratamento farmacológico , Compostos de Platina/uso terapêutico , Telomerase/antagonistas & inibidores , Antineoplásicos/farmacologia , Senescência Celular/efeitos dos fármacos , Inibidores Enzimáticos/uso terapêutico , Humanos , Neoplasias/patologia , Compostos de Platina/farmacologia , Telomerase/química
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