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1.
An Acad Bras Cienc ; 93(suppl 4): e20210406, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34878049

RESUMO

Synthetic antioxidants (e.g.butylhydroxytoluene, BHT) are routinely used for to restrict oxidative processes of meat products, but they are implicated as harmful to the health of humans. Therefore natural alternatives, such as plant antioxidants, have been sought as replacements. Plant antioxidants when added to the diet can be incorporated into meat and reduce the need for the addition of synthetic antioxidants during processing. The objective of this study was to evaluate the effects of ethanol extracts of mango seeds (EEMS) in the diet of pigs on qualitative parameters and total antioxidant capacity of mortadella produced from these animals. Thirty-two pigs with an average 60 days of age were distributed among four treatments: control=no antioxidant; BHT=200ppm BHT; EEMS200=200ppm of EEMS and EEMS400=400ppm of EEMS. At 145 days of age the animals were slaughtered and loin was removed for the preparation of mortadella, which was analyzed during 90 days of storage at 4°C. A higher content of polyphenolic compounds and, total antioxidant capacity in mortadellas processed with meat of animals which consumed the EEMS400 ration after 60 and 90 days of storage was observed. EEMS polyphenolic antioxidants incorporated into pork through the diet results in an increase of total antioxidant capacity in the processed product.


Assuntos
Mangifera , Carne de Porco , Carne Vermelha , Animais , Antioxidantes , Dieta , Etanol , Oxirredução , Extratos Vegetais/farmacologia , Sementes , Suínos
2.
Nutr Cancer ; 69(2): 229-237, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28094599

RESUMO

Physical activity (PA) and vitamin D are thought to affect colorectal cancer prognosis. The present study investigates associations between 25(OH)D3 and PA in prospectively followed colorectal cancer patients in the ColoCare study. At 6, 12, and 24 mo after surgery, patients donated a blood sample, wore an accelerometer for 10 consecutive days, and completed a PA questionnaire. Plasma 25-hydroxyvitamin D3 (25(OH)D3) levels were measured by high-performance liquid chromatography. We tested associations using partial correlations and multivariate linear regression analysis, adjusted for season, age, and body mass index. A total of 137 assessments of 25(OH)D3 levels and PA were conducted (58 at 6 mo, 51 at 12 mo, and 28 at 24 mo). More than 60% of the patients were vitamin D-deficient (25(OH)D3 ≤20 ng/ml), independent of study time point. At 6-mo follow-up, accelerometry-based vigorous and moderate-to-vigorous PAs were positively associated with 25(OH)D3 levels (P = 0.04; P = 0.006,). PA together with season was a significant predictor of elevated 25(OH)D3 levels. Our results suggest that the majority of colorectal cancer patients may suffer from vitamin D deficiency. Engaging in PA may be an effective approach to increase their 25(OH)D3 levels.


Assuntos
Calcifediol/sangue , Neoplasias Colorretais/sangue , Acelerometria , Idoso , Neoplasias Colorretais/cirurgia , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Deficiência de Vitamina D/sangue
3.
Eur J Epidemiol ; 32(11): 961-971, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28884317

RESUMO

To investigate the association of serum 25-hydroxyvitamin D (25(OH)D3) with survival in a large prospective cohort study of colorectal cancer (CRC) patients. The study population consisted of 2,910 patients diagnosed with CRC between 2003 and 2010 who participated in the DACHS study, a multicenter study from Germany with comprehensive long-term follow-up. 25(OH)D3 was determined in serum samples collected shortly after cancer diagnosis by High Performance Liquid Chromatography-Electro Spray Ionization-Mass Spectrometry. Analyses of survival outcomes were performed using Cox regression with comprehensive adjustment for relevant confounders. The majority (59%) of CRC patients were vitamin D deficient (serum 25(OH)D3 levels <30 nmol/L). During a median follow-up of 4.8 years, 787 deaths occurred, 573 of which were due to CRC. Compared to patients in the highest 25(OH)D3 quintile (>45.20 nmol/L), those in the lowest 25(OH)D3 quintile (<11.83 nmol/L) had a strongly increased mortality. Adjusted hazard ratios (95% Confidence Interval) were 1.78 (1.39-2.27), 1.65 (1.24-2.21), 1.32 (1.03-1.71) and 1.48 (1.18-1.85) for all-cause mortality, CRC-specific mortality, recurrence-free and disease-free survival, respectively. Subgroup analyses did not show any significant effect modification across strata defined by sex, age, stage, body mass index, or the late entry. Dose-response analyses showed a strong inverse relationship between serum 25(OH)D3 levels and survival endpoints at 25(OH)D3 levels <30 nmol/L, and no association with mortality at higher 25(OH)D3 levels. Vitamin D deficiency is highly prevalent in CRC patients and a strong independent predictor of poor prognosis. The possibility of enhancing CRC prognosis by vitamin D supplementation, ideally combined with outdoor physical activity, should be evaluated by randomized controlled trials focusing on patients with vitamin D deficiency.


Assuntos
Calcifediol/sangue , Neoplasias Colorretais/epidemiologia , Sobreviventes , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia , Adulto , Idoso , Neoplasias Colorretais/sangue , Suplementos Nutricionais , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Vitamina D/análogos & derivados
4.
Z Naturforsch C J Biosci ; 69(9-10): 363-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25711036

RESUMO

A new phenolic-type compound containing a nitrogenous, heterocyclic-fused ring from the fruit of the argan tree, Argania spinosa (Skeels L.), is described. This and another already known compound also isolated in the course of the work belong to an obscure and rare class of natural products, the amino phenolics.


Assuntos
Fenóis/química , Extratos Vegetais/química , Sapotaceae/química , Frutas/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Óleos de Plantas/química , Árvores
5.
ACS Pharmacol Transl Sci ; 6(5): 727-737, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37200805

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a deadly malignancy with no effective treatment, particularly in the advanced stage. This study explored the antiproliferative activity of khasianine against pancreatic cancer cell lines of human (Suit2-007) and rat (ASML) origin. Khasianine was purified from Solanum incanum fruits by silica gel column chromatography and analyzed by LC-MS and NMR spectroscopy. Its effect in pancreatic cancer cells was evaluated by cell proliferation assay, chip array and mass spectrometry. Proteins showing sensitivity to sugars, i.e. sugar-sensitive lactosyl-Sepharose binding proteins (LSBPs), were isolated from Suit2-007 cells by competitive affinity chromatography. The eluted fractions included galactose-, glucose-, rhamnose- and lactose-sensitive LSBPs. The resulting data were analyzed by Chipster, Ingenuity Pathway Analysis (IPA) and GraphPad Prism. Khasianine inhibited proliferation of Suit2-007 and ASML cells with IC50 values of 50 and 54 µg/mL, respectively. By comparative analysis, khasianine downregulated lactose-sensitive LSBPs the most (126%) and glucose-sensitive LSBPs the least (85%). Rhamnose-sensitive LSBPs overlapped significantly with lactose-sensitive LSBPs and were the most upregulated in data from patients (23%) and a pancreatic cancer rat model (11.5%). From IPA, the Ras homolog family member A (RhoA) emerged as one of the most activated signaling pathways involving rhamnose-sensitive LSBPs. Khasianine altered the mRNA expression of sugar-sensitive LSBPs, some of which were modulated in data from patients and the rat model. The antiproliferative effect of khasianine in pancreatic cancer cells and the downregulation of rhamnose-sensitive proteins underscore the potential of khasianine in treating pancreatic cancer.

6.
J Lipid Res ; 53(11): 2459-68, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22829651

RESUMO

Myristoyl-CoA (CoA):protein N-myristoyltransferase (NMT) catalyzes protein modification through covalent attachment of a C14 fatty acid (myristic acid) to the N-terminal glycine of proteins, thus promoting protein-protein and protein-membrane interactions. NMT is essential for the viability of numerous human pathogens and is also up-regulated in several tumors. Here we describe a new, nonradioactive, ELISA-based method for measuring NMT activity. After the NMT-catalyzed reaction between a FLAG-tagged peptide and azido-dodecanoyl-CoA (analog of myristoyl-CoA), the resulting azido-dodecanoyl-peptide-FLAG was coupled to phosphine-biotin by Staudinger ligation, captured by plate-bound anti-FLAG antibodies and detected by streptavidin-peroxidase. The assay was validated with negative controls (including inhibitors), corroborated by HPLC analysis, and demonstrated to function with fresh or frozen tissues. Recombinant murine NMT1 and NMT2 were characterized using this new method. This versatile assay is applicable for exploring recombinant NMTs with regard to their activity, substrate specificity, and possible inhibitors as well as for measuring NMT-activity in tissues.


Assuntos
Acil Coenzima A/metabolismo , Aciltransferases/metabolismo , Ácidos Mirísticos/metabolismo , Idoso , Animais , Linhagem Celular Tumoral , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Especificidade por Substrato
7.
J Cell Physiol ; 227(2): 718-28, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21465477

RESUMO

Disturbance in vitamin A metabolism seems to be an important attribute of cancer cells. Retinoids, particularly retinoic acid, have critical regulatory functions and appear to modulate tumor development and progression. The key step of vitamin A metabolism is the esterification of all-trans retinol, catalyzed by lecithin/retinol acyltransferase (LRAT). In this work, we show that malignant melanoma cells are able to esterify all-trans retinol and subsequently isomerize all-trans retinyl esters (RE) into 11-cis retinol, whereas their benign counterparts-melanocytes are not able to catalyze these reactions. Besides, melanoma cell lines express lecithin/retinol acyltranseferase both at the mRNA and protein levels. In contrast, melanocytes do not express this enzyme at the protein level, but mRNA of lecithin/retinol acyltransefrase could still be present at mRNA level. RPE65 is expressed in both melanocytic counterparts, and could be involved in the subsequent isomerization of RE produced by lecithin/retinol acyltransefrase to 11-cis retinol. Cellular retinol-binding protein 2 does not appear to be involved in the regulation of all-trans retinol esterification in these cells. Expression of LRAT and RPE65 can be modulated by retinoids. We propose that the post-transcriptional regulation of lecithin/retinol acyltransefrase could be involved in the differential expression of this enzyme. Besides, activities of LRAT and RPE65 may be important for removal of all-trans retinal which is the substrate for retinoic acid production in skin cells. Consequently, the decreasing cellular amount of retinoic acid and its precursor molecules could result in a change of gene regulation.


Assuntos
Aciltransferases/metabolismo , Melanócitos/metabolismo , Melanoma/metabolismo , Vitamina A/farmacologia , Aciltransferases/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Melanócitos/citologia , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Receptores X de Retinoides/genética , Receptores X de Retinoides/metabolismo , Proteínas Celulares de Ligação ao Retinol/genética , Proteínas Celulares de Ligação ao Retinol/metabolismo , Tretinoína , cis-trans-Isomerases
8.
Int J Cancer ; 131(9): 1983-90, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22322480

RESUMO

A diet high in linoleic acid (an ω-6 PUFA) increased the formation of miscoding etheno (ε)--DNA adducts in WBC-DNA of women, but not in men (Nair et al., Cancer Epidemiol Biomark Prev 1997;6:597-601). This gender specificity could result from an interaction between ω-6 PUFA intake and estrogen catabolism, via redox-cycling of 4-hydroxyestradiol (4-OH-E(2) ) and subsequent lipid peroxidation (LPO). In this study, we investigated whether in premenopausal women LPO-derived adducts in WBC-DNA are affected by serum concentration of 2- and 4-hydroxyestradiol metabolites and by fatty acid intake. DNA extracted from buffy coat and plasma samples, both blindly coded from healthy women (N = 124, median age 40 year) participating in the EPIC-Heidelberg cohort study were analyzed. Three LPO-derived exocyclic DNA adducts, εdA, εdC and M(1) dG were quantified by immuno-enriched (32) P-postlabelling and estradiol metabolites by ultra-sensitive GC-mass spectrometry. Mean M(1) dG levels in WBC-DNA were distinctly higher than those of εdA and εdC, and all were positively and significantly interrelated. Serum levels of 4-OH-E(2) , but not of 2-OH-E(2) , metabolites were positively related to etheno DNA adduct formation. Positive correlations existed between M(1) dG levels and linoleic acid intake or the ratios of dietary linoleic acid/oleic acid and PUFA/MUFA. Aerobic incubation of 4-OH-E(2) , arachidonic acid and calf thymus DNA yielded two to threefold higher etheno DNA adduct levels when compared with assays containing 2-OH-E(2) instead. In conclusion, this study is the first to compare M(1) dG and etheno-DNA adducts and serum estradiol metabolites in human samples in the same subjects. Our results support a novel mechanistic link between estradiol catabolism, dietary ω-6 fatty acid intake and LPO-induced DNA damage supported by an in vitro model. Similar studies in human breast epithelial tissue and on amplification of DNA-damage in breast cancer patients are in progress.


Assuntos
Adutos de DNA/biossíntese , Gorduras na Dieta/administração & dosagem , Estrogênios/metabolismo , Ácidos Graxos Ômega-6/administração & dosagem , Peroxidação de Lipídeos , Linfócitos/metabolismo , Pré-Menopausa , Adulto , Estudos de Coortes , Dano ao DNA , Estradiol/análogos & derivados , Estradiol/sangue , Estrogênios/sangue , Estrogênios de Catecol , Feminino , Humanos , Ácido Linoleico/administração & dosagem , Ácido Linoleico/metabolismo , Linfócitos/citologia , Ácido Oleico/metabolismo
9.
Chem Res Toxicol ; 25(1): 162-9, 2012 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-22148471

RESUMO

Methylation of cytidine at dCpdG sequences regulates gene expression and is altered in many chronic inflammatory diseases. Inflammation generates lipid peroxidation (LPO) products which can react with deoxycytidine, deoxyadenosine, and deoxyguanosine in DNA to form pro-mutagenic exocyclic etheno-nucleoside residues. Since 5-methyl-2'-deoxycytidine (5mdC) residues exhibit increased nucleophilicity at N3, they should be even better targets for LPO products. We synthesized and characterized 3,N(4)-etheno-5-methyl-2'-deoxycytidine-3'-phosphate and showed that LPO products can indeed form the corresponding etheno-5mdC (ε5mdC) lesion in DNA in vitro. Our newly developed (32)P-postlabeling method was subsequently used to detect ε5mdC lesions in DNA from human white blood cells, lung, and liver at concentrations 4-10 times higher than that observed for etheno adducts on nonmethylated cytidine. Our new detection method can now be used to explore the hypothesis that this DNA lesion perturbs the DNA methylation status.


Assuntos
Adutos de DNA , DNA/metabolismo , Desoxicitidina/análogos & derivados , Acetaldeído/análogos & derivados , Acetaldeído/metabolismo , Ácido Araquidônico/metabolismo , Metilação de DNA , Desoxicitidina/metabolismo , Feminino , Genoma , Humanos , Leucócitos/metabolismo , Peroxidação de Lipídeos , Fígado/metabolismo , Pulmão/metabolismo
10.
Exp Dermatol ; 20(4): 373-5, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20812966

RESUMO

Vitamin A is a pivotal regulator of differentiation and growth of developing and adult skin. Retinoic acid is the major physiologically active form of vitamin A regulating the expression of different genes through retinoic acid nuclear receptors. Here, we present evidence that other vitamin A derivates - retinol and retinal - are also capable of functioning as regulators of gene expression in the keratinocyte cell line HaCaT. We have shown that all-trans retinol (ATRol) and all-trans retinal (ATRal) are capable of modulating gene expression in keratinocytes, which is not because of vitamin A metabolism in the cells, and retinol and retinal modulate gene expression through nuclear receptors: retinoic acid receptors (RARs) and retinoid X receptors (RXRs). Based on the data, we propose that ATRol and all-trans retinal, in addition to all-trans retinoic acid, can function as important regulators of gene expression manifesting their effect through the nuclear receptors RARs and RXRs.


Assuntos
Regulação da Expressão Gênica , Retinaldeído/genética , Vitamina A/genética , Humanos , Queratinócitos/metabolismo , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Retinaldeído/metabolismo , Receptores X de Retinoides/genética , Receptores X de Retinoides/metabolismo , Transcrição Gênica , Vitamina A/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-31729295

RESUMO

OBJECTIVE: This study aimed to evaluate the effect of the aqueous extract of Anvillea radiate (A. radiata) aerial parts (AEAR) on arterial blood pressure in normotensive and hypertensive rats. METHODS: The effect of the acute and sub-chronic administration of AEAR on the following blood pressure parameters: systolic blood pressure (SBP), mean blood pressure (MBP), diastolic blood pressure (DBP), and heart rate (HR) was evaluated in normotensive and L-NAME induced hypertensive rats. In the second experiment, the vasorelaxant effect of AEAR was assessed in isolated aortic rings from rats with functional endothelium pre-contracted with epinephrine (EP) or KCl, and six antagonists/ inhibitors were used to explore the mechanisms of action involved in the vasorelaxant effect. In order to determine the phytochemical contents of Anvillea radiata, HPLC-ESI-MS analysis was conducted. RESULTS: Daily oral administration of AEAR (100 mg/kg) provoked a significant decrease in SBP, MBP, and DBP without affecting HR in hypertensive rats. In addition, AEAR (0.08-0.64 mg/ml) revealed a vasorelaxant effect in thoracic aortic rings pre-contracted by EP (10 µM) or KCl (80 mM). This effect was reduced in the presence of Nifedipine, L-Name or Methylene blue. The polyphenolic compounds of AEAR were determined. CONCLUSION: This study revealed that AEAR possesses a potent antihypertensive activity and its vasorelaxant activity seems to be mediated through Ca2+ channels, direct nitric oxide (NO), and NO/cGMP pathways. Chlorogenic acid and caffeic acid identified in A. radiata could be at least partially responsible for the antihypertensive activity of this extract.


Assuntos
Anti-Hipertensivos/uso terapêutico , Asteraceae/química , Hipertensão/tratamento farmacológico , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Animais , Anti-Hipertensivos/isolamento & purificação , Pressão Sanguínea/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Hipertensão/induzido quimicamente , Hipertensão/fisiopatologia , Masculino , NG-Nitroarginina Metil Éster , Fitoterapia , Extratos Vegetais/análise , Ratos , Ratos Wistar , Espectrometria de Massas por Ionização por Electrospray
12.
Food Res Int ; 134: 109221, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32517933

RESUMO

Coffee (Coffea arabica L.) is an important commodity, involving about 500 million people from the cultivation of the coffee trees to final consumption of infusions of the ground roasted coffee beans. In contrast to a considerable amount of research performed on green coffee beans, there are relatively few studies regarding the chemical constituents of coffee leaves. Hemileia vastatrix is a parasite, specific to coffee plants and causes coffee leaf rust, which is a very destructive disease. Some coffee plants have natural resistance which is mainly linked to a gene and specific host resistance response. An increase in flavonoid production may be related to fungal disease resistance, with the levels and flavonoid types being an early physiological response to rust infection. Trace inorganic elements can be related to many roles in the defense response of higher plants and can be used as a biomarker for some diseases. To address this, coffee leaves from 16 different cultivars of Coffea arabica were harvested from Minas Gerais, Brazil (susceptible and resistant to rust) and their polyphenolic compounds were extracted using the QuEChERS technique and quantitated by HPLC-ESI-MS. The same leaves were decomposed using an acid mixture in a block digester and the content of Al, Cu, Mg, Mn, Ni, Sn and Zn was quantitated by ICP-OES. Principal component analysis (PCA) was applied and we could establish a relation between polyphenolic and trace element concentration in the leaves with resistance to rust infection. On this basis in this preliminary study we were able to separate the resistant from the susceptible cultivars. The main compounds responsible for this differentiation were the content of chlorogenic acid and magnesium in the leaves. The content of polyphenolic compounds was lower in susceptible cultivars and a diametric effect was observed between Mn and Mg concentrations. This study shows potential for the discrimination of resistant and susceptible coffee trees based on the analyses of both trace element and polyphenolic concentration.


Assuntos
Coffea/química , Doenças das Plantas/microbiologia , Folhas de Planta/química , Polifenóis/química , Oligoelementos/química , Basidiomycota , Biomarcadores , Coffea/classificação , Análise Multivariada , Análise de Componente Principal
13.
Cancer Epidemiol Biomarkers Prev ; 29(2): 460-469, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31740522

RESUMO

BACKGROUND: Xenobiotic-metabolizing enzymes (XME) play a critical role in the activation and detoxification of several carcinogens. However, the role of XMEs in colorectal carcinogenesis is unclear. METHODS: We investigated the expression of XMEs in human colorectal tissues among patients with stage I-IV colorectal cancer (n = 71) from the ColoCare Study. Transcriptomic profiling using paired colorectal tumor and adjacent normal mucosa tissues of XMEs (GSTM1, GSTA1, UGT1A8, UGT1A10, CYP3A4, CYP2C9, GSTP1, and CYP2W1) by RNA microarray was compared using Wilcoxon rank-sum tests. We assessed associations between clinicopathologic, dietary, and lifestyle factors and XME expression with linear regression models. RESULTS: GSTM1, GSTA1, UGT1A8, UGT1A10, and CYP3A4 were all statistically significantly downregulated in colorectal tumor relative to normal mucosa tissues (all P ≤ 0.03). Women had significantly higher expression of GSTM1 in normal tissues compared with men (ß = 0.37, P = 0.02). By tumor site, CYP2C9 expression was lower in normal mucosa among patients with rectal cancer versus colon cancer cases (ß = -0.21, P = 0.0005). Smokers demonstrated higher CYP2C9 expression levels in normal mucosa (ß = 0.17, P = 0.02) when compared with nonsmokers. Individuals who used NSAIDs had higher GSTP1 tumor expression compared with non-NSAID users (ß = 0.17, P = 0.03). Higher consumption of cooked vegetables (>1×/week) was associated with higher CYP3A4 expression in colorectal tumor tissues (ß = 0.14, P = 0.007). CONCLUSIONS: XMEs have lower expression in colorectal tumor relative to normal mucosa tissues and may modify colorectal carcinogenesis via associations with clinicopathologic, lifestyle, and dietary factors. IMPACT: Better understanding into the role of drug-metabolizing enzymes in colorectal cancer may reveal biological differences that contribute to cancer development, as well as treatment response, leading to clinical implications in colorectal cancer prevention and management.


Assuntos
Carcinógenos/metabolismo , Neoplasias Colorretais/patologia , Perfilação da Expressão Gênica/estatística & dados numéricos , Mucosa Intestinal/enzimologia , Xenobióticos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Aminas/metabolismo , Antioxidantes/metabolismo , Carcinogênese/patologia , Feminino , Compostos Heterocíclicos/metabolismo , Humanos , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , não Fumantes/estatística & dados numéricos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Estudos Prospectivos , Fumantes/estatística & dados numéricos
14.
Mol Cancer Res ; 6(1): 110-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18184973

RESUMO

Proteins involved in the visual signaling cascade show light-dependent expression levels in photoreceptor cells. Recently, these proteins have been described to be expressed in neuroectodermal tumors and to function as cancer-retina antigens. Here, we show that light can down-regulate gene expression of rhodopsin, transducin, and cyclic guanosine 3',5'-monophosphate phosphodiesterase 6 (PDE6) and up-regulate guanylyl cyclase 1, recoverin, and arrestin in human melanoma cells in vitro, comparable to physiologic changes earlier observed in photoreceptor cells. Similar modulation can be detected at the protein level in melanoma cells except for no changes in PDE6 protein levels. Two regulatory pathways have been identified: Sp1/Sp3/Sp4 proteins for rhodopsin and PDE6, and mitogen-activated protein kinases for recoverin and arrestin. The visual cascade and retinoic acid as its derivate do not play any role in this process. Putative explanations for light-dependent modulation of cancer-retina antigen expression in melanoma cells are discussed.


Assuntos
Antígenos de Neoplasias/genética , Proteínas do Olho/genética , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Luz , Antígenos de Neoplasias/metabolismo , Butadienos/farmacologia , Linhagem Celular Tumoral , Nucleotídeo Cíclico Fosfodiesterase do Tipo 6/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/efeitos da radiação , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/efeitos da radiação , Proteínas do Olho/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Melanócitos/efeitos da radiação , Modelos Biológicos , Nitrilas/farmacologia , Células Fotorreceptoras/efeitos dos fármacos , Células Fotorreceptoras/metabolismo , Células Fotorreceptoras/efeitos da radiação , Biossíntese de Proteínas/efeitos dos fármacos , Biossíntese de Proteínas/efeitos da radiação , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição Sp/genética , Fatores de Transcrição Sp/metabolismo , Tretinoína/farmacologia , Visão Ocular/efeitos dos fármacos , Visão Ocular/efeitos da radiação , Proteínas rho de Ligação ao GTP/metabolismo
15.
Artigo em Inglês | MEDLINE | ID: mdl-30421687

RESUMO

AIMS: Arganimide A (4,4-dihydroxy-3,3-imino-di-benzoic acid) is a compound belonging to a family of aminophenolics found in fruit of Argania spinosa. The purpose of this study was to investigate the glucose and lipid lowering activity of Arganimide A (ARG A). METHODS: The effect of a single dose and daily oral administration of Arganimide A (ARG A) on blood glucose levels and plasma lipid profile was tested in normal and streptozotocin (STZ) diabetic rats at a dose of 2 mg/kg body weight. RESULTS: Single oral administration of ARG A reduced blood glucose levels from 26.50±0.61 mmol/L to 14.27±0.73 mmol/L (p<0.0001) six hours after administration in STZ diabetic rats. Furthermore, blood glucose levels were decreased from 5.35±0.30 mmol/L to 3.57±0.17 mmol/L (p<0.0001) and from 26.50±0.61 mmol/L to 3.67±0.29 mmol/L (p<0.0001) in normal and STZ diabetic rats, respectively, after seven days of treatment. Moreover, no significant changes in body weight in normal and STZ rats were shown. According to the lipid profile, the plasma triglycerides levels were decreased significantly in diabetic rats after seven days of ARG treatment (p<0.05). Moreover, seven days of ARG A treatment decreased significantly the plasma cholesterol concentrations (p<0.001). CONCLUSION: ARG A possesses glucose and lipid-lowering activity in diabetic rats and this natural compound may be beneficial in the treatment of diabetes.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Hipolipemiantes/uso terapêutico , Extratos Vegetais/uso terapêutico , Sapotaceae , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Frutas , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Hipolipemiantes/isolamento & purificação , Hipolipemiantes/farmacologia , Masculino , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar
16.
Environ Sci Pollut Res Int ; 26(6): 5588-5600, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30612345

RESUMO

The surface group characteristics of mango cultivar peels and seeds were evaluated by infrared spectra, PZC, and functional group composition. The adsorption/reduction of chromium (VI) in aqueous solutions was investigated by varying pH, contact time, initial Cr(VI) concentration, and adsorbent amount. The results show that both peel and seed powders of the mango cultivars showed significant adsorption/reduction capacity for Cr(VI) and that the desorption process obeys pseudo-second-order kinetics. Optimal adsorption occurred at pH 1.0, using a Cr(VI) concentration of 100 mg/L. On average, at pH 1.0, and a concentration of 3 g/L, the maximum adsorption/reduction capacity of Cr(VI) was 83% (peels 76%, seeds 90%). Of the mango powders tested, the most efficient were Tommy seed (100%) and Coite peel (98%) followed by Coite seed (96%) and Tommy peel powders (95%). The adsorption/reduction of Cr(VI) was complete (100%) by the mango seed, in comparison to the peel powders (97%) after 180 min. The data indicates that mango waste products, such as seed and peel powders, are both excellent candidates for the remediation of Cr(VI) from aqueous systems and due to the higher concentration of gallates and galloyl glucosides, the mango seed powders should be the powders of choice for future remediation projects.


Assuntos
Cromo/química , Recuperação e Remediação Ambiental/métodos , Mangifera , Resíduos , Poluentes Químicos da Água/química , Adsorção , Cromo/análise , Concentração de Íons de Hidrogênio , Cinética , Sementes , Poluentes Químicos da Água/análise
17.
Food Res Int ; 115: 493-503, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599970

RESUMO

There are relatively few studies concerning the use of coffee leaves for medicinal purposes and the composition of secondary plant substances. Therefore, we identified and quantitated polyphenolic compounds along with caffeine present in methanol extracts of Coffea arabica leaves from three different regions of Brazil (Ceará, Minas Gerais and São Paulo) by HPLC-ESI-MS. In addition, correlations between polyphenolic content of the coffee leaves and antioxidant assays DPPH, FRAP and ORAC were evaluated. Fifteen compounds belonging to three classes of polyphenols (xanthones, chlorogenic acids and flavonoids) along with the alkaloid caffeine were detected. The mean concentration of total polyphenolic compounds in the leaves of C. arabica, harvested from three different regions of Brazil was quite variable. The highest values were detected in the coffee leaves harvested in Minas Gerais (n = 4) at 40.80(13.00) g/kg (SD), followed by coffee leaves harvested in São Paulo (n = 20) at 24.79(20.19) g/kg, and the lowest in coffee leaves harvested in Ceará (n = 11) in the Northeast of Brazil at 10.30(5.61) g/kg. The three classes of polyphenols, all showed excellent correlations in the antioxidant assays. Coffee leaf tea, appears to be an excellent functional beverage, with its high content of polyphenolic compounds, which may render positive biologic effects, when inbibed as part of the normal human diet.


Assuntos
Cafeína/análise , Coffea/química , Suplementos Nutricionais , Flavonoides/análise , Folhas de Planta/química , Xantonas/análise , Antioxidantes/análise , Brasil , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Café/química , Extratos Vegetais/análise , Polifenóis/análise
18.
Food Chem ; 110(1): 57-61, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26050165

RESUMO

The primary aim of this study was to determine the oxidative stability of argan oils by using peroxides and conjugated diene hydroperoxides measurements as analytical indicators. Both food and cosmetic argan oils were investigated. Their oxidative stability was also determined by monitoring the relative changes of their fatty acid profiles by (1)H NMR. In addition, valuable information regarding minor components as well as the acyl positional distribution, were obtained for both grades by high field (1)H and (13)C NMR, respectively. Given that the cosmetic and food grades have a similar profile and content of phenolic antioxidants, vitamers, and squalene, it appears that the ratio of fatty acid aliphatic to bisallylic CH2 groups, much higher in argan oils than in other vegetable oils, is responsible for their higher thermal stability.

19.
Biomedicines ; 6(3)2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30111701

RESUMO

Advanced glycation end products (AGEs) represent a set of molecules that contribute directly to the initiation and aggravation of diseases associated with ageing. AGEs are produced by the reaction between reducing sugars (or α-dicarbonyl compounds), proteins, and amino acid residues. Previous in vitro methods using non-enzymatic procedures described in the literature require an incubation period of 1⁻3 weeks to generate AGEs. In this study, the reaction time for the formation of AGEs (48 and 3 h) was significantly reduced by adaptation of methods previously described in the literature and coupling them to the free radical generation system termed hypoxanthine/xanthine oxidase assay. The incorporation of this assay into the experimental system accelerated the production of AGEs as a result of the formation of reactive oxygen species (ROS), as shown by increased fluorescence. The capacity of different classes of chemical compounds (aminoguanidine, chlorogenic acid, rutin, and methanol extracts of Hancornia speciosa Gomes) to inhibit protein glycation by acting as scavenging agents of α-dicarbonyl species was evaluated. Aminoguanidine and, especially, rutin identified in the leaf extracts of H. speciosa Gomes showed a high capacity to act as scavengers of reactive carbonyl species RCS-trapping, resulting in the inhibition of AGEs formation.

20.
Nutrients ; 10(4)2018 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-29671819

RESUMO

Current knowledge on the role of retinol in the prognosis of patients with colorectal cancer (CRC) is very limited. We investigated the association of serum retinol levels with survival outcomes in a large cohort of 2908 CRC patients from Germany. Retinol concentrations were determined in serum collected shortly after diagnosis by mass spectrometry. Associations between serum retinol levels and survival outcomes were assessed using multivariable Cox regression and dose-response analyses. The joint association of serum retinol and serum 25-hydroxyvitamin D3 (25(OH)D3) with survival outcomes was also examined. During a median follow-up of 4.8 years, 787 deaths occurred, 573 of which were due to CRC. Dose-response curves showed an inverse relationship between serum retinol levels and survival endpoints in the range of <2.4 µmol/L, but no associations at higher levels. Low (<1.2 µmol/L) versus high (≥2.4 µmol/L) serum retinol levels were associated with poorer overall survival (Hazard ratio (HR) = 1.46, 95% confidence interval (CI) = 1.19⁻1.78, P-trend = 0.0003) and CRC-specific survival (HR = 1.69, 95% CI = 1.33⁻2.15, P-trend < 0.0001). Joint presence of low serum retinol (<1.2 µmol/L) and low 25(OH)D3 (<30 nmol/L) was associated with a particularly strong decrease in overall and CRC-specific survival. Low serum retinol levels were identified as a predictor of poor survival in CRC patients, in particular when co-occurring with low serum concentrations of 25(OH)D3. The clinical implications of these findings require further investigation.


Assuntos
Neoplasias Colorretais/sangue , Neoplasias Colorretais/mortalidade , Vitamina A/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Calcifediol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Análise de Sobrevida
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