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1.
Foods ; 10(9)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34574220

RESUMO

Several processed food products may contain toxic compounds considered risk factors for human health. Known for its possible carcinogenic effects, acrylamide is an organic compound periodically analyzed by the entities responsible for consumer safety. Knowing the acrylamide content of food offers the possibility of implementing corrective measures when needed, targeted at lowering its level. The aim of the paper was to screen for the presence of acrylamide in four products consumed almost daily in Romania and calculate acrylamide exposure by consuming one serving. Expressed in µg/kg coffee has the highest average acrylamide content (199), followed by potato chips (134), pretzels (120), and bread (14). Results regarding the acrylamide content in one serving showed the highest levels of acrylamide in pretzels (10.20 µg/serving), followed by potato chips (4.00 µg/serving), coffee (2.20 µg/cup), and bread (0.40 µg/slice). The calculation of the acrylamide content for one serving of the studied products will facilitate the following studies on the dietary acrylamide intake of the Romanian population, studies which, to our knowledge, have not been performed so far.

2.
Molecules ; 26(11)2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34067400

RESUMO

Syringa vulgaris L. (common lilac) is one of the most popular ornamental species, but also a promising not comprehensively studied source of bioactive compounds with important therapeutic potential. Our study was designed to characterize the chemical composition and to assess the antioxidant and cytotoxic properties of ethanolic extracts obtained from S. vulgaris L. flowers, leaves, bark, and fruit. The chemical profile of the ethanolic extracts was investigated using chromatographic (HPLC-DAD-ESI+, GC-MS) and spectral (UV-Vis, FT-IR) methods, while the protective effect against free radicals was evaluated in vitro by different chemical assays (DPPH, FRAP, CUPRAC). The cytotoxic activity was tested on two tumoral cell lines, HeLa, B16F10, using the MTT assay. Significant amounts of free or glycosylated chemical components belonging to various therapeutically important structural classes, such as phenyl-propanoids (syringin, acteoside, echinacoside), flavonoids (quercetin, kaempferol derivatives) and secoiridoids (secologanoside, oleuropein, 10-hydroxy oleuropein, demethyloleuropein, syringalactone A, nuzhenide, lingstroside) were obtained for the flowers, leaves and bark extracts, respectively. Furthermore, MTT tests pointed out a significant cytotoxic potential expressed in a non-dose-dependent manner toward the tumoral lines. The performed methods underlined that S. vulgaris extracts, in particular belonging to flowers and leaves, represent valuable sources of compounds with antioxidant and antitumoral potential.


Assuntos
Antioxidantes/química , Flores/química , Estresse Oxidativo , Extratos Vegetais/química , Folhas de Planta/química , Syringa/química , Animais , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Cromatografia Gasosa-Espectrometria de Massas , Glucosídeos , Glicosídeos , Células HeLa , Humanos , Melanoma Experimental , Camundongos , Fenóis , Fenilpropionatos , Folhas de Planta/metabolismo , Quercetina/análise , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Int J Mol Sci ; 18(2)2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-28178210

RESUMO

Thrombospondin-1 (TSP-1) is a potent endogenous inhibitor of both physiological and pathological angiogenesis, widely studied as a target in drug development for treating cancer. Several studies performed in the cardiovascular field on TSP-1 are contradictory, the role of TSP-1 in the physiopathology of cardiovascular disorders (CVDs) being, for the moment, incompletely understood and may be due to the presence of several domains in its structure which can stimulate many cellular receptors. It has been reported to inhibit NO-mediated signaling and to act on the angiogenesis, tissue perfusion, endothelial cell proliferation, and homeostasis, so we aimed to quantify the effect Perindopril has on TSP-1 plasma levels in hypertensive patients with endothelial dysfunction in comparison with other antihypertensive drugs, such as beta blockers, calcium channel blockers, and diuretics, in a chronic treatment. As a conclusion, patients under treatment with Perindopril had increased plasma levels of TSP-1 compared with other hypertensive patients and with the control group. The results of this study confirms the pleiotropic properties of Perindopril: anti-proliferative, anti-inflammatory, with effects showed by quantifying a single biomarker: TSP-1.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Hipertensão/sangue , Perindopril/farmacologia , Perindopril/uso terapêutico , Trombospondina 1/sangue , Biomarcadores , Pressão Sanguínea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Estudos de Casos e Controles , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Resultado do Tratamento
4.
Curr Drug Deliv ; 14(8): 1178-1188, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28128068

RESUMO

BACKGROUND: Melanoma is known as the most dangerous form of skin cancer; whereas the malignant choroidal melanoma is an orphan disease known as the most common primary intraocular malignancy in adults. Literature suggests that the consumption of garlic and mistletoe leads to a reduced risk of developing cancer. OBJECTIVE: The aim of this study was the obtaining and the characterization of polymer structures containing mistletoe or garlic extract. METHODS: The structures were obtained in a polyaddition process combined with a spontaneous emulsification; they were characterized by pH, size, Zeta potential and DSC measurements, evaluation of encapsulation efficacy, penetrability through membranes and in vitro cytotoxicity tests. RESULTS: The microstructures present sizes between 1.05 and 2.60 µm and Zeta potentials between -7 and +36 mV. A good encapsulation was observed on different evaluations (88-92%). It was determined that approx. 30% of polymer microstructures containing vegetal extracts pass through an artificial membrane in 4 days. An in vitro cytotoxicity test revealed that these products are safe for administration. The analysis of antitumor efficacy indicates that garlic extracts have important effects after 48 and 72 hours on A375 cells; however, polymer microstructures with herbal extracts did not reveal antiproliferative activities on A375 cells because these polymer structures present a slow degradation. CONCLUSION: Sterile eye drops solutions based on polymer microstructures containing garlic or mistletoe extracts were obtained; the sample based on garlic extracts may be used in the pharmaceutical field as drug carrier with an antiproliferative effect which occurs after a prolong period.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Coroide/tratamento farmacológico , Portadores de Fármacos/química , Alho/química , Melanoma/tratamento farmacológico , Erva-de-Passarinho/química , Poliuretanos/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Tamanho da Partícula , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Relação Estrutura-Atividade
5.
Molecules ; 19(7): 9798-817, 2014 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-25006787

RESUMO

Structure-toxicity relationships for a series of 75 azo and azo-anilide dyes and five diazonium salts were developed using Hydractinia echinata (H. echinata) as model species. In addition, based on these relationships, predictions for 58 other azo-dyes were made. The experimental results showed that the measured effectiveness Mlog(1/MRC50) does not depend on the number of azo groups or the ones corresponding to metobolites, but it is influenced by the number of anilide groups, as well as by the substituents' positions within molecules. The conformational analysis pointed out the intramolecular hydrogen bonds, especially the simple tautomerization of quinoidic (STOH) or aminoidic (STNH2) type. The effectiveness is strongly influenced by the "push-pull" electronic effect, specific to two hydroxy or amino groups separated by an azo moiety (double alternate tautomery, (DAT), to the -COOH or -SO3H groups which are located in ortho or para position with respect to the azo group. The levels of the lipophylic/hydrophilic, electronic and steric equilibriums, pointed out by the Mlog(1/MRC50) values, enabled the calculation of their average values Clog(1/MRC50) ("Köln model"), characteristic to one derivative class (class isotoxicity). The azo group reduction and the hydrolysis of the amido/peptidic group are two concurrent enzymatic reactions, which occur with different reaction rates and mechanisms. The products of the partial biodegradation are aromatic amines. No additive or synergic effects are noticed among them.


Assuntos
Compostos Azo/química , Compostos Azo/toxicidade , Hidrozoários/efeitos dos fármacos , Testes de Toxicidade/métodos , Animais , Relação Estrutura-Atividade
6.
Molecules ; 19(4): 4924-40, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24747649

RESUMO

Oleanolic and ursolic acids are natural triterpenic compounds with pentacyclic cholesterol-like structures which gives them very low water solubility, a significant disadvantage in terms of bioavailability. We previously reported the synthesis of inclusion complexes between these acids and cyclodextrins, as well as their in vivo evaluation on chemically induced skin cancer experimental models. In this study the synergistic activity of the acid mixture included inside hydroxypropyl-gamma-cyclodextrin (HPGCD) was monitored using in vitro tests and in vivo skin cancer models. The coefficient of drug interaction (CDI) was used to characterize the interactions as synergism, additivity or antagonism. Our results revealed an increased antitumor activity for the mixture of the two triterpenic acids, both single and in complex with cyclodextrin, thus proving their complementary biologic activities.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Melanoma/tratamento farmacológico , Ácido Oleanólico/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Triterpenos/farmacologia , gama-Ciclodextrinas/química , 9,10-Dimetil-1,2-benzantraceno , Animais , Antineoplásicos Fitogênicos/farmacocinética , Disponibilidade Biológica , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos , Sinergismo Farmacológico , Feminino , Humanos , Melanoma/induzido quimicamente , Melanoma/patologia , Camundongos , Ácido Oleanólico/farmacocinética , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/patologia , Solubilidade , Triterpenos/farmacocinética , Raios Ultravioleta , Ácido Ursólico
7.
Cancer Cell Int ; 13: 75, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23890195

RESUMO

BACKGROUND: One of the most popular and versatile model of murine melanoma is by inoculating B16 cells in the syngeneic C57BL6J mouse strain. A characterization of different B16 modified cell sub-lines will be of real practical interest. For this aim, modern analytical tools like surface enhanced Raman spectroscopy/scattering (SERS) and MTT were employed to characterize both chemical composition and proliferation behavior of the selected cells. METHODS: High quality SERS signal was recorded from each of the four types of B16 cell sub-lines: B164A5, B16GMCSF, B16FLT3, B16F10, in order to observe the differences between a parent cell line (B164A5) and other derived B16 cell sub-lines. Cells were incubated with silver nanoparticles of 50-100 nm diameter and the nanoparticles uptake inside the cells cytoplasm was proved by transmission electron microscopy (TEM) investigations. In order to characterize proliferation, growth curves of the four B16 cell lines, using different cell numbers and FCS concentration were obtained employing the MTT proliferation assay. For correlations doubling time were calculated. RESULTS: SERS bands allowed the identification inside the cells of the main bio-molecular components such as: proteins, nucleic acids, and lipids. An "on and off" SERS effect was constantly present, which may be explained in terms of the employed laser power, as well as the possible different orientations of the adsorbed species in the cells in respect to the Ag nanoparticles. MTT results showed that among the four tested cell sub-lines B16 F10 is the most proliferative and B164A5 has the lower growth capacity. Regarding B16FLT3 cells and B16GMCSF cells, they present proliferation ability in between with slight slower potency for B16GMCSF cells. CONCLUSION: Molecular fingerprint and proliferation behavior of four B16 melanoma cell sub-lines were elucidated by associating SERS investigations with MTT proliferation assay.

8.
Chem Cent J ; 7: 121, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23856382

RESUMO

BACKGROUND: In the last years pectin and other hydrocolloids were tested for improving the color stability and the retention of bioactive compounds in gelled fruit-based products. In line with these concerns, our study has been directed to quantify the changes in antioxidant status and color indices of blackberry jam obtained with different types of pectin (degree of esterification: DE, degree of amidation: DA) and doses in response to processing and storage for 1, 3 and 6 months at 20°C. RESULTS: Blackberry jam was obtained by a traditional procedure used in households or small-scale systems with different commercial pectins (HMP: high-methoxyl pectin, LMP: low-methoxyl pectin and LMAP: low-methoxyl amidated pectin) added to three concentrations (0.3, 0.7 and 1.0%) and investigated in terms of total monomeric anthocyanins (TMA), antioxidant capacity expressed as ferric reducing antioxidant power (FRAP), total phenolics (TP), color density (CD) and percent of polymeric color, PC (%). Thermal processing resulted in significant depreciation of analyzed parameters reported to the corresponding values of fresh fruit as follows: TMA (69-82%), TP (33-55%) and FRAP (18-52%). Biologically active compounds and color were best retained one day post-processing in jams with LMAP followed by samples with LMP and HMP. Storage for 6 months brings along additional dramatic losses reported to the values recorded one day post-processing as follows: TMA (31-56%), TP (29-51%) and FRAP (20-41%). Also, both processing and storage resulted in significant increases in PC (%). The pectin type and dosage are very influential factors for limiting the alterations occurring in response to processing and storage. The best color retention and the highest TMA, TP and FRAP were achieved by LMAP, followed by LMP and HMP. Additionally, a high level of bioactive compounds in jam could be related to a high dose of pectin. LMAP to a level of 1% is the most indicated to provide the highest antioxidant properties in jam. CONCLUSIONS: The retention of bioactive compounds and jam color stability were strongly dependent on the pectin type and dosage. By a proper selection of pectin type and dose could be limited the losses recorded in response to processing and storage.

9.
Chem Cent J ; 6(1): 137, 2012 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-23158079

RESUMO

BACKGROUND: Pentacyclic triterpenes, mainly betulin and betulinic acid, are valuable anticancer agents found in the bark of birch tree. This study evaluates birch bark extracts for the active principles composition. RESULTS: New improved extraction methods were applied on the bark of Betula pendula in order to reach the maximum content in active principles. Extracts were analyzed by HPLC-MS, Raman, SERS and 13C NMR spectroscopy which revealed a very high yield of betulin (over 90%). Growth inhibiting effects were measured in vitro on four malignant human cell lines: A431 (skin epidermoid carcinoma), A2780 (ovarian carcinoma), HeLa (cervix adenocarcinoma) and MCF7 (breast adenocarcinoma), by means of MTT assay. All of the prepared bark extracts exerted a pronounced antiproliferative effect against human cancer cell lines. In vivo studies involved the anti-inflammatory effect of birch extracts on TPA-induced model of inflammation in mice. CONCLUSIONS: The research revealed the efficacy of the extraction procedures as well as the antiproliferative and anti-inflammatory effects of birch extracts.

10.
Chem Cent J ; 6(1): 87, 2012 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-22892194

RESUMO

BACKGROUND: Polymers have been considered as important materials in fabrication of microstructures for various medical purposes including drug delivery. This study evaluates polyurethane as material for hollow microstructures preparation. RESULTS: Polyurethane microstructures were obtained by interfacial polyaddition combined with spontaneous emulsification and present slightly acid pH values. Scanning electron microscopy revealed the existence of irregular shapes and agglomerated microstructures. The material is heat resistant up to 280°C. Good results were recorded on murine skin tests in case of polyurethane microstructures based on isophorone diisocyanate. Mesenchymal stem cells viability presents good results for the same sample after 48 hours based on the Alamar Blue test. CONCLUSIONS: The research revealed the reduced noxiousness of this type of microstructures and consequently the possibility of their use for therapeutic purposes.

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