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1.
Toxicology ; 502: 153715, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38211720

RESUMO

BPA is used in a wide range of consumer products with very concern toxicological properties. The European Union has restricted its use to protect human health. Industry has substituted BPA by BPA analogues. However, there is a lack of knowledge about their impacts. In this work, BPA and 5 BPA analogues (BPS, BPAP, BPAF, BPFL and BPC) have been studied in classical SH-SY5Y and the alternative 3D in vitro models after 24 and 96 h of exposure. Cell viability, percentage of ROS, cell cycle phases as well as the morphology of the spheroids were measured. The 2D model was more sensitive than the 3D models with differences in cell viability higher than 60% after 24 h of exposure, and different mechanisms of ROS production. After chronic exposure, both models were more affected in comparison to the 24 h exposure. After a recovery time (96 h), the spheroids exposed to 2.5-40 µM were able to recover cell viability and the morphology. Among the BPs tested, BPFL>BPAF>BPAP and >BPC revealed higher toxicological effects, while BPS was the only one with lower effects than BPA. To conclude, the SH-SY5Y 3D model is a suitable candidate to perform more reliable in vitro neurotoxicity tests.


Assuntos
Antineoplásicos , Neuroblastoma , Humanos , Espécies Reativas de Oxigênio , Compostos Benzidrílicos/toxicidade , Dano ao DNA , Neurônios
2.
Foods ; 12(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37685126

RESUMO

Bread crust constitutes an important by-product of the bakery industry, and its utilization for the isolation of melanoidins to be used as a functional ingredient can enhance its added value and contribute to health. The aim of this study was to evaluate the bioaccessibility, bioactivity, and genoprotective effect of melanoidins derived from bread crust. Bioaccessibility was assessed in gastric, intestinal digestion, and colonic fermentation fractions. The results revealed a relationship between bioaccessible melanoidins and their type (common or soft bread). No cytotoxicity effects were observed for bioaccessible fractions, as assessed by MTT and RTA methods, and they did not affect the distribution of E-cadherin in Caco-2 cells, confirming their ability to maintain membrane integrity. Furthermore, our study demonstrated that the gastrointestinal and colonic fermentation fractions successfully transported across the intestinal barrier, without affecting cell permeability, and showed antioxidant activity on the basolateral side of the cell monolayer. Remarkably, both fractions displayed a significant genoprotective effect in Caco-2 cells. Our findings provide crucial insights into the relationship between the melanoidins and their bioactivity and genoprotective effect. These results demonstrated the potential of bioaccessible melanoidins as valuable bioactive compounds for the development of functional foods, without showing toxic effects on gastrointestinal cells.

3.
Antioxidants (Basel) ; 12(7)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37507996

RESUMO

Olive oil and lycopene are foods that have potent antioxidant activity. The objective was to determine the effects of consumption of olive oil enriched with lycopene on oxidative stress biomarkers in hypercholesterolemic subjects. We examined the effects of oil enriched with lycopene extract daily intake during 1 month on plasma antioxidant capacity, lipids profile (triacylgycerols, total cholesterol, cHDL; cLDL, ox-LDL), biomarkers of oxidative stress, and inflammatory markers related with atherosclerosis risk (C-reactive protein (CRP), IL-6; sDC4L) in subjects hypercholesteremics (cholesterol > 220 mg/dL). In the group consuming olive oil-lycopene, significant increases (p < 0.05) in the levels of plasma lycopene concentration (0.146 ± 0.03 versus 0.202 ± 0.04 (µmol/L)), α-carotene (0.166 ± 0.064 versus 0.238 ± 0.07) and in ß-carotene (0.493 ± 0.187 versus 0.713 ± 0.221) were observed. These results are linked with the increases of plasma antioxidants and decreases biomarkers of oxidative stress (carbonyl groups, malondialdehyde and 8-hydroxy-deoxiguanosine) observed in hypercholesterolemic group. In relation to lipid profile, a significant decrease was observed in the levels of ox-LDL (781 ± 302 versus 494 ± 200), remaining unchanged the levels of TG, cholesterol, HDL and LDL-c. Regarding inflammatory biomarkers, the levels of CRP and IL-6 decreased significantly. The positive results obtained in this study support the use of olive oil enriched with lycopene to reduce the risk of coronary disease.

4.
Antioxidants (Basel) ; 12(6)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37371978

RESUMO

The clinical relevance of stress biomarkers in newborns is well established. Currently, oxidative stress (OS) parameters are seen to play an important role in neonatal resuscitation guidelines, and a link has been observed between the amount of oxygen delivered and the level of OS and the development of various pathologies. The aim of the current study was to investigate changes in neonatal plasma and urine OS status during the first hours after birth. A lower antioxidant capacity (TAC) and higher levels of malondialdehyde in blood were observed in newborns at the time of birth compared with results 48 h postnatally. The urine revealed a significant and progressive increase in TAC and creatinine during the first 36 h of life, with a progressive decline thereafter. Meanwhile, malondialdehyde in urine samples showed no significant differences over time. Overall, the correlation between blood and urine parameters was poor, except for the relationship between umbilical vein glutathione reduced/oxidized ratio and urine malondialdehyde (r = 0.7; p = 0.004) and between TAC in the umbilical artery and urine (r = -0.547; p = 0.013). The biomarkers evaluated in this study could be established as reference values for neonatal OS.

5.
Food Chem ; 427: 136625, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37364313

RESUMO

White wine pomace products (wWPP) represent an innovative strategy as a functional food ingredient to be used as a seasoning both for their technological and functional properties. Nevertheless, the bioactive compounds of wWPP used as a seasoning could be modified during storage. The seasoning in the meat, regardless of the storage method used, modified its phenolic profile and in its bioaccessible fractions, while maintaining a high total antioxidant capacity and total polyphenol content. The contact of the seasoning with the meat can be considered safe as it does not show cytotoxicity in the Caco-2 cells. Additionally, the ability to modulate the cell oxidative stress of the bioaccessible fractions and the potential benefits on microbiota by the colonic fermentation fraction, suggest its potential use as a functional ingredient, without being affected by storage. These results are novel and may help to establish the value of this product as a functional ingredient.


Assuntos
Vitis , Vinho , Humanos , Animais , Vinho/análise , Antioxidantes/análise , Galinhas , Células CACO-2 , Fenóis/análise , Carne
6.
Food Funct ; 14(3): 1785-1794, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36723046

RESUMO

Melanoidins isolated from bakery by-products are proposed as new sustainable ingredients for bakery products. The colour, odour profile, texture, water activity, and antioxidant capacity of two bakery food models, fat and fat-free, enriched with 2% and 4% soft bread and common bread melanoidins, were analysed. The colour of the bakery food models with melanoidins was darker than that of the respective control; the fat-free models with melanoidins showed higher values of hardness than the control, while no significant effect was observed in the fat models; the water activity did not change compared to the control; the odour profile was significantly modified with different effects depending on the type of melanoidin quantity added and the food model (fat or fat-free); and the antioxidant capacity increased proportionally to the quantity of melanoidin added. In general, melanoidins from soft bread exhibited a higher effect than the melanoidins from common bread. The melanoidins isolated from both fat and fat-free bakery food models did not show cytotoxicity nor did they modify the levels of reactive oxygen species in Caco-2 cells. Therefore, the results seem to indicate the favourable potential of bread melanoidins as new sustainable ingredients for bakery products.


Assuntos
Antioxidantes , Pão , Humanos , Antioxidantes/farmacologia , Pão/análise , Células CACO-2 , Polímeros
7.
Crit Rev Food Sci Nutr ; 62(27): 7427-7448, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33951976

RESUMO

The wine pomace is the main winery by-products that suppose an economic and environmental problem and their use as a functional ingredient are being increasingly recognized as a good and inexpensive source of bioactive compounds. In this sense, it is known the potential health properties of wine pomace products in the prevention of disorders associated with oxidative stress and inflammation such as endothelial dysfunction, hypertension, hyperglycemia, diabetes, obesity. Those effects are due to the bioactive compounds of wine pomace and the mechanisms concern especially modulation of antioxidant/prooxidant activity, improvement of nitric oxide bioavailability, reduction of pro-inflammatory cytokines and modulation of antioxidant/inflammatory signal pathways. This review mainly summarizes the mechanisms of wine pomace products as modulators of oxidative status involved in cell pathologies as well as their potential therapeutic use for cardiovascular diseases. For this purpose, the review provides an overview of the findings related to the wine pomace bioactive compounds profile, their bioavailability and the action mechanisms for maintaining the redox cell balance involved in health benefits. The review suggests an important role for wine pomace product in cardiovascular diseases prevention and their regular food intake may attenuate the development and progression of comorbidities associated with cardiovascular diseases.


Assuntos
Doenças Cardiovasculares , Vitis , Vinho , Antioxidantes/análise , Disponibilidade Biológica , Doenças Cardiovasculares/prevenção & controle , Citocinas/metabolismo , Humanos , Óxido Nítrico , Oxirredução , Estresse Oxidativo , Transdução de Sinais , Vinho/análise
8.
Antioxidants (Basel) ; 10(10)2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34679658

RESUMO

Hypoxic ischemic encephalopathy (HIE) is one of the main causes of morbidity and mortality during the neonatal period, despite treatment with hypothermia. There is evidence that oxidative damage plays an important role in the pathophysiology of hypoxic-ischemic (HI) brain injury. Our aim was to investigate whether postnatal allopurinol administration in combination with hypothermia would reduce oxidative stress (OS) biomarkers in an animal model of HIE. Postnatal 10-day rat pups underwent unilateral HI of moderate severity. Pups were randomized into: Sham operated, hypoxic-ischemic (HI), HI + allopurinol (HIA), HI + hypothermia (HIH), and HI + hypothermia + allopurinol (HIHA). Biomarkers of OS and antioxidants were evaluated: GSH/GSSG ratio and carbonyl groups were tested in plasma. Total antioxidant capacity (TAC) was analyzed in plasma and cerebrospinal fluid, and 8-iso-prostaglandin F2α was measured in brain tissue. Plasma 2,2'-azinobis-(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) levels were preserved in those groups that received allopurinol and dual therapy. In cerebrospinal fluid, only the HIA group presented normal ferric reducing ability of plasma (FRAP) levels. Protein oxidation and lipid peroxidation were significantly reduced in all groups treated with hypothermia and allopurinol, thus enhancing neuroprotection in HIE.

9.
Foods ; 10(7)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206875

RESUMO

Red wine pomace products (WPP) have antimicrobial activities against human pathogens, and it was suggested that they have a probable anti-Listeria effect. This manuscript evaluates the intestinal cell monolayer invasive capacity of Listeria monocytogenes strains obtained from human, salmon, cheese, and L. innocua treated with two WPP (WPP-N and WPP-C) of different polyphenol contents using Caco-2 and SW480 cells. The invasion was dependent of the cell line, being higher in the SW480 than in the Caco-2 cell line. Human and salmon L. monocytogenes strains caused cell invasion in both cell lines, while cheese and L. innocua did not cause an invasion. The phenolic contents of WPP-N are characterized by high levels of anthocyanin and stilbenes and WPP-C by a high content of phenolic acids. The inhibitory effect of the WPPs was dependent of the strain and of the degree of differentiation of the intestinal cells line. The inhibition of Listeria invasion by WPPs in the SW480 cell line, especially with WPP-C, were higher than the Caco-2 cell line inhibited mainly by WPP-N. This effect is associated with the WPPs' ability to protect the integrity of the intestinal barrier by modification of the cell-cell junction protein expression. The gene expression of E-cadherin and occludin are involved in the L. monocytogenes invasion of both the Caco-2 and SW480 cell lines, while the gene expression of claudin is only involved in the invasion of SW480. These findings suggest that WPPs have an inhibitory L. monocytogenes invasion effect in gastrointestinal cells lines.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 251: 119472, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33493936

RESUMO

Kaolinite-rich Cretaceous clay sediment samples from Burgos (Spain) have been analyzed by elemental analysis, X-ray fluorescence, inductively coupled plasma mass spectrometry, X-ray diffraction and different spectroscopic techniques, as Fourier Transform Infrared, ultraviolet-visible and electron paramagnetic resonance. The clay sediment samples mainly contain quartz, muscovite and kaolinite. Different radicals, as A- and B-Centers in kaolinite and organic paramagnetic species, are detected. An illite/kaolinite FTIR band ratio parameter (IKB) is proposed to infer the illite/kaolinite proportion, which can be useful to graphically visualize the iron-substituted Al(III) sites. Studies of the activity as scavengers of DPPH and ABTS radicals show that samples with a larger amount of orthorhombic Fe(III) ions replacing Al(III) ions exhibit a higher antioxidant capacity.

11.
Food Chem ; 343: 128405, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33127227

RESUMO

Melanoidins contribute to organoleptic properties of processed foods and exert benefits in health. The aim of this study was to isolate and characterize melanoidins from baked products (common bread, soft bread and biscuits), evaluate their cytotoxicity and determine their suitability as functional additives. Extraction yield, spectrophotometric characteristics, colorimetric properties, antioxidant capacity, and cytotoxicity of melanoidins were assessed. Among the studied products, soft bread had the highest extraction throughput. Melanoidins from biscuit showed the highest antioxidant capacity, closely followed by those of soft bread. Melanoidins did not exert cytotoxic effects on Caco-2 and HUVEC cells (viability was >80%). Nevertheless, incubation of HUVEC cells with melanoidins from common bread and biscuit slightly decreased viability, whereas gastrointestinal digestion of such melanoidins softened the decrease in cell viability. This study point to soft bread as a safe and efficient source of melanoidins, that could be potentially used in the future as functional ingredient.


Assuntos
Antioxidantes/farmacologia , Pão , Polímeros/farmacologia , Antioxidantes/química , Disponibilidade Biológica , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Digestão , Células Endoteliais da Veia Umbilical Humana , Humanos , Polímeros/isolamento & purificação , Polímeros/farmacocinética
12.
Heliyon ; 6(11): e05396, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33294652

RESUMO

The functional renal epithelium is composed of differentiated and polarized tubular cells with a strong actin cortex and specialized cell-cell junctions. If, under pathological conditions, these cells have to resist higher kidney osmolarity, they need to activate diverse mechanisms to survive external nephrotoxic agents such as inflammation and oxidative stress. Wine pomace polyphenols exert protective effects on renal cells. In this study, two wine-pomace products and their protective effects upon promotion and preservation of normal cell differentiation and attenuation of oxalate-induced type II epithelial mesenchymal transition (EMT) are evaluated. Treatment with gastrointestinal and colonic bioavailable fractions from red (rWPP) and white (wWPP) wine pomaces, both in the presence and the absence of oxalate, showed similar cell numbers and nuclear size than the non-treated differentiated MDCK cells. Immunofluorescence analysis showed the reduction of morphological changes and the preservation of cellular junctions for the rWPP and wWPP pre-treatment of cells exposed to oxalate injury. Hence, both rWPP and wWPP attenuated oxalate type II EMT in MDCK cells that conserved their epithelial morphology and cellular junctions through the antioxidant activities of grape pomace polyphenols.

13.
Food Funct ; 11(9): 7878-7891, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32812564

RESUMO

Endothelial dysfunction is associated with cardiovascular diseases and involves a chronic inflammatory process that together with oxidative stress increases the permeability of the vascular endothelium. The aim of this study was to evaluate the role of red and white wine pomace products (rWPPs and wWPPs) in the maintenance of endothelial integrity in hyperglycemia of EA.hy926 endothelial cells. EA.hy926 endothelial cells exposed to hyperglycemia were treated with the in vitro digested fractions of rWPPs and wWPPs. A Real Time Cellular Analysis (RTCA) system was used to evaluate the endothelial monolayer integrity after INF-γ stimulation of pre-treated endothelial cells with the digested fractions. The changes in cell viability, NO, ROS and NOX4 were recorded and actin cytoskeleton and E-cadherin junctions were evaluated by immunofluorescence. All digested fractions prevent the hyperglycemic actions in the cell viability and NO/ROS balance. The inflammatory mediator INF-γ and hyperglycemia caused a decrease in RTCA adhesion of the EA.hy926 endothelial cell monolayer. Pre-treatment with all digested fractions enhanced the EA.hy926 endothelial monolayer integrity and maintained actin cytoskeleton and E-cadherin junctions. These in vitro studies elucidate that the anti-hyperglycemic and anti-inflammatory actions of wine pomace products involve a decrease in ROS production and the stabilization of junction proteins via modulation of VE-cadherin and actin cytoskeleton suggesting a potential prevention of endothelial damage by these natural products.


Assuntos
Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Hidroxibenzoatos/farmacologia , Vinho/análise , Citoesqueleto de Actina/metabolismo , Antígenos CD/metabolismo , Caderinas/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Humanos , Hidroxibenzoatos/análise
14.
Food Funct ; 11(2): 1661-1671, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32030390

RESUMO

Wine pomace by-products are an important source of phenolic acids with significant health benefits. However, phenolic acid bioavailability in vivo has been little studied and there are few comparative studies on bioavailability between red and white wine pomace and the effect of intake of different doses. The qualitative and quantitative profile of phenolic acid metabolites in plasma and urine samples from Wistar rats was obtained by gas chromatography/mass detection, after oral administration of four doses (50, 100, 150, and 300 mg) of both the red and the white wine pomace products (rWPP and wWPP, respectively). The antioxidant capacity of the plasma samples assessed by both the ABTS and the FRAP levels was also evaluated. The results showed that neither the bioavailability nor the antioxidant capacity in vivo of the rWPP increased at high doses. However, both parameters were dependent on the intake of the wWPP.


Assuntos
Preparações de Plantas , Polifenóis/farmacocinética , Vitis/química , Vinho/análise , Administração Oral , Animais , Antioxidantes/análise , Antioxidantes/metabolismo , Disponibilidade Biológica , Masculino , Preparações de Plantas/administração & dosagem , Preparações de Plantas/química , Preparações de Plantas/farmacocinética , Polifenóis/sangue , Polifenóis/química , Polifenóis/urina , Ratos , Ratos Wistar
15.
J Inorg Biochem ; 180: 69-79, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29247869

RESUMO

Thiosemicarbazones (TSCs), and their copper derivatives, have been extensively studied mainly due to the potential applications as antitumor compounds. A part of the biological activity of the TSC-CuII complexes rests on their reactivity against cell reductants, as glutathione (GSH). The present paper describes the structure of the [Cu(PTSC)(ONO2)]n compound (1) (HPTSC=pyridine-2-carbaldehyde thiosemicarbazone) and its spectroscopic and magnetic properties. ESI studies performed on the reaction of GSH with 1 and the analogous [{Cu(PTSC*)(ONO2)}2] derivative (2, HPTSC*=pyridine-2-carbaldehyde 4N-methylthiosemicarbazone) show the absence of peaks related with TSC-Cu-GSH species. However GSH-Cu ones are detected, in good agreement with the release of CuI ions after reduction in the experimental conditions. The reactivity of 1 and 2 with cytochrome c and myoglobin and their activities against HT-29 and SW-480 colon carcinoma cell lines are compared with those shown by the free HPTSC and HPTSC* ligands.


Assuntos
Neoplasias Colorretais/patologia , Cobre/química , Glutationa/química , Tiossemicarbazonas/química , Tiossemicarbazonas/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Cristalografia por Raios X , Citocromos c/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Glutationa/metabolismo , Humanos , Estrutura Molecular , Mioglobina/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Neurochem Res ; 37(5): 1085-90, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22297726

RESUMO

Although coffee has antioxidant capacity, it is not known which of its bioactive compounds is responsible for it, nor has it been analyzed in experimental cerebral infarction. We studied the effect one of its compounds, 3-caffeoylquinic acid (3-CQA), at doses of 4, 25 and 100 µg on plasma antioxidant capacity and plasma polyphenol content, measuring the differences before and after inducing a cerebral infarction in an experimental rat model. We compared them with 3-caffeoylquinic-free controls. The increase in total antioxidant capacity was only higher than in controls in 3-CQA treated animals with the highest dose. This increase in antioxidant capacity was not due to an increase in polyphenols. No differences between the experimental and control group were found regarding polyphenol content and cerebral infarction volume. In conclusion, this increase in antioxidant capacity in the group that received the highest dose of 3-CQA was not able to reduce experimental cerebral infarction.


Assuntos
Antioxidantes/metabolismo , Infarto Cerebral/metabolismo , Ácido Clorogênico/farmacologia , Café/química , Polifenóis/metabolismo , Animais , Masculino , Ratos , Ratos Sprague-Dawley
17.
Biochem Cell Biol ; 90(2): 173-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22257103

RESUMO

Increased oxidative stress and indoleamine-2,3-dioxygenase (IDO) activity have been reported in cancer, but their relationship with chemotherapy remains unknown. The aim of the present study was to examine wether the chemotherapy treatments used in colorectal cancer had an additional effect on oxidative stress and on IDO activity. Plasma samples were collected from 27 colorectal cancer patients on cytostatic treatment, 27 with cytostatic drugs plus monoclonal antibodies (cytostatic-Mabs) and 15 non-treated patients. All patients with colorectal cancer had high plasma malondialdehyde (MDA), thioredoxin (Trx) levels, and elevated IDO activity in plasma (IDOp) and in dendritic cells (IDOc). This study shows that treatment with cytostatics have an effect on oxidative stress by increasing MDA levels and by decreasing Trx levels and IDO activity. However, treatment with cytostatic-Mabs showed no effect on MDA levels but decreased Trx levels, and the IDO activity showed values similar to the healthy group. Significant correlations between plasma IDO activity and the levels of Trx (r = 0.2062, p < 0.05) and MDA (r = 0.2873, p < 0.005) were observed. Furthermore, our study suggests that IDO activity measured as kynurenine levels could be used as a marker of the response to the chemotherapy treatments, although further studies are necessary.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/sangue , Indolamina-Pirrol 2,3,-Dioxigenase/sangue , Tiorredoxinas/sangue , Idoso , Antineoplásicos/administração & dosagem , Estudos de Casos e Controles , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/imunologia , Tratamento Farmacológico , Feminino , Humanos , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Estresse Oxidativo
18.
J Sci Food Agric ; 90(7): 1238-44, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20394007

RESUMO

BACKGROUND: This study was designed to evaluate and compare antioxidant capacity and radical scavenging activity of naringin and its aglycone by different in vitro assays. The effects of flavanones on lipid peroxidation, glutathione (GSH) oxidation and DNA cleavage were also assessed. RESULTS: The results showed that naringenin exhibited higher antioxidant capacity and hydroxyl and superoxide radical scavenger efficiency than naringin. Our results evidenced that glycosylation attenuated the efficiency in inhibiting the enzyme xanthine oxidase and the aglycone could act like a more active chelator of metallic ions than the glycoside. Additionally, naringenin showed a greater effectiveness in the protection against oxidative damage to lipids in a dose-dependent manner. Both flavanones were equally effective in reducing DNA damage. However, they show no protective effect on oxidation of GSH. CONCLUSION: The data obtained support the importance of characterizing the ratio naringin/naringenin in foods when they are evaluated for their health benefits.


Assuntos
Antioxidantes/farmacologia , Fragmentação do DNA/efeitos dos fármacos , Flavanonas/farmacologia , Glicosídeos/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Animais , Bovinos , Quelantes/farmacologia , Relação Dose-Resposta a Droga , Flavanonas/metabolismo , Sequestradores de Radicais Livres/farmacologia , Glutationa/metabolismo , Glicosídeos/metabolismo , Glicosilação , Radical Hidroxila/metabolismo , Masculino , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxidos/metabolismo , Xantina Oxidase/antagonistas & inibidores
19.
J Transl Med ; 8: 15, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-20146801

RESUMO

BACKGROUND: Although there have been many studies on the p73 gene, some of its functions still remain unclear. There is little research on the relationship between p73 gene transcription and its protein expression and the response to certain drugs such as oxaliplatin and cetuximab, which are drugs currently used in colorectal cancer.The purpose of this study was to evaluate the impact of TAp73 expression on oxaliplatin and cetuximab-based chemotherapy in colorectal cancer cell lines with different K-Ras and B-Raf mutational status. METHODS: TAp73 was analyzed in three colorectal tumor cell lines HT-29, SW-480 and Caco-2. mRNA TAp73 was determined using Real time PCR; TAp73 protein by immunoblotting and cell viability was analyzed by the MTT method. RESULTS: We found that mRNA and TAp73 protein were decreased in cells treated with oxaliplatin (in monotherapy or combined with cetuximab) when B-Raf is mutated. This was statistically significant and was also associated with higher cell viability after the treatment. CONCLUSIONS: Here, for the first time we report, that there is a signaling loop between B-Raf activation and p73 function.Low expression of TAp73 in colorectal cancer cell lines with mutated B-Raf may be involved in the lack of response to oxaliplatin in monotherapy or combined with cetuximab.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Colorretais , Proteínas de Ligação a DNA/genética , Mutação , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Supressoras de Tumor/genética , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Linhagem Celular Tumoral , Cetuximab , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Proteínas Nucleares/metabolismo , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina , Proteínas Proto-Oncogênicas B-raf/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/fisiologia , Proteína Tumoral p73 , Proteínas Supressoras de Tumor/metabolismo
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