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2.
Carcinogenesis ; 42(8): 1026-1036, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-33999989

RESUMO

Hepatocellular carcinoma (HCC) presents with a high treatment resistance and poor prognosis. Early diagnosis and preventive approaches such as chemoprevention are essential for the HCC control. Therefore, we evaluated the chemopreventive effects of butyrate-containing structured lipids (STLs) administered during the promotion stage of hepatocarcinogenesis in rats submitted to the 'resistant hepatocyte' (RH) model. Administration of butyrate-containing STLs inhibited the incidence and mean number of visible hepatic nodules per rat and reduced the number and area of glutathione S-transferase placental form-positive (GST-P+) preneoplastic focal lesions in the livers. This was accompanied by the induction of apoptosis and an increased level of hepatic butyric acid. Treatment with butyrate-containing STLs resulted in increased histone H3 lysine 9 (H3K9) acetylation, reduction of total histone deacetylase (HDAC) activity, and lower levels of HDAC4 and HDAC6 proteins. The chemopreventive effect of butyrate-containing STLs was also associated with the increased nuclear compartmentalization of p53 protein and reduced expression of the Bcl-2 protein. In addition, rats treated with butyrate-containing STLs showed decreased DNA damage and telomerase activity in the livers. These results demonstrate that the suppressive activity of butyrate-containing STLs is associated with inhibition of elevated during hepatocarcinogenesis chromatin-modifying proteins HDAC4 and HDAC6, subcellular redistribution of the p53 protein, and decreased DNA damage and telomerase activity.


Assuntos
Butiratos/metabolismo , Dano ao DNA , Glutationa S-Transferase pi/metabolismo , Desacetilase 6 de Histona/metabolismo , Histona Desacetilases/metabolismo , Lipídeos/química , Neoplasias Hepáticas Experimentais/patologia , Telomerase/metabolismo , Animais , Carcinogênese , Caspase 3/metabolismo , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Hepáticas Experimentais/genética , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Wistar , Frações Subcelulares/enzimologia , Proteína Supressora de Tumor p53/metabolismo , Ácido alfa-Linolênico/metabolismo
3.
Food Technol Biotechnol ; 58(4): 411-422, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33505204

RESUMO

RESEARCH BACKGROUND: New sources of docosahexaenoic acid have recently been investigated aiming at infant formula fortification and dietary supplementation, among which the single cell oil with 40-50% of this acid. EXPERIMENTAL APPROACH: For this purpose, such an oil was blended with caprylic acid in amount substance ratio ranging from 1:1 to 5:1 and the blends were interesterified using either Novozym 435 or Lipozyme TL IM as the catalyst. The influence of the amount of excess free caprylic acid in the substrate, as well as the type of enzyme on the triacylglycerol rearrangement resulting from the synthesis of the structured lipids were evaluated. RESULTS AND CONCLUSIONS: The regiospecific lipase Lipozyme TL IM seemed to induce transesterification among single cell oil triacylglycerols preferably by acidolysis with caprylic acid, which was directly proportional to the ratio of this acid in the substrate. In reactions catalyzed by the non-regiospecific lipase Novozym 435, a higher incorporation of caprylic acid into single cell oil triacylglycerols was observed than when using Lipozyme TL IM, independently of the oil/caprylic acid molar ratio. NOVELTY AND SCIENTIFIC CONTRIBUTION: These results revealed the importance of combining the choice of the type of lipase, either regiospecific or not, with the amount ratios of free fatty acids and the substrate in acidolysis when aiming to produce structured lipids as a source of docosahexaenoic acid.

4.
Food Funct ; 9(8): 4274-4281, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30027199

RESUMO

The viability and the in vitro gastrointestinal survival of Bifidobacterium animalis subsp. lactis Bb-12 (Bifidobacterium Bb-12) in table spreads with different proportions of milk fat (MF) and palm olein (PO) (MF : PO 40 : 60 and MF : PO 20 : 80) were investigated for up to 28 days of storage at 5 °C. Moreover, qPCR alone and combined with propidium monoazide (PMA) were compared with the traditional plate count method for determining the in vitro gastrointestinal survival of Bifidobacterium Bb-12 in table spreads after 35 days of storage. Formulations showed probiotic viabilities ranging from 8 to 9 log CFU g-1 across the whole storage period, and the milk fat and palm olein in different concentrations did not affect this viability. Bifidobacterium Bb-12 showed good survival after six hours under in vitro simulated gastrointestinal conditions during the studied storage period, with average reductions of 1.70 (MF : PO 40 : 60) and 2.16 log CFU g-1 (MF : PO 20 : 80). The results of the qPCR with PMA treatment and the plate count method were similar and the qPCR without PMA treatment was shown to overestimate the Bifidobacterium Bb-12 populations. However, the MF : PO 40 : 60 spread showed a Bb-12 population between 0.76 and 1.43 log CFU g-1 higher than that of MF : PO 20 : 80. Thus, the results showed that table spreads, especially food matrices with a higher proportion of milk fat, are suitable for the incorporation of Bifidobacterium Bb-12.


Assuntos
Bifidobacterium animalis/crescimento & desenvolvimento , Gorduras/química , Trato Gastrointestinal/microbiologia , Leite/química , Probióticos/química , Simbióticos/análise , Animais , Bifidobacterium animalis/química , Bifidobacterium animalis/fisiologia , Bovinos , Composição de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Viabilidade Microbiana , Óleo de Palmeira/química , Estresse Fisiológico
5.
Food Res Int ; 99(Pt 1): 713-719, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28784535

RESUMO

The objective of this work was to produce structured lipids (SLs) from olive oil (O), soybean oil (S), and fully hydrogenated crambe oil - FHCO (C) mixtures by enzymatic interesterification, comparing Lipozyme TL IM and Rhizopus sp. performances as catalysts, and to evaluate their physical and chemical modifications. Among other blends (OC 90:10 w/w and SC 90:10 w/w), OSC (45:45:10, w/w), presented the most nutritionally interesting amounts of mono- and polyunsaturated fatty acids, as well as behenic acid. Interesterification caused an increase in crystallization time and a decrease in the solid fat content in all blends. The fatty acid redistribution in the TAGs caused a change in thermal behavior, leading to a decrease in the onset and end temperatures during crystallization, which indicates that new TAGs were formed. Regarding regiospecificity, Lipozyme TL IM lipase acted randomly, while Rhizopus sp. lipase was specific for the sn-1,3 position. Therefore, it was possible to synthesize SLs presenting different physical and chemical properties, compared to the original OSC blend, containing behenic acid at the sn-1,3 position and unsaturated fatty acids at the sn-2 position, by enzymatic interesterification catalyzed either by Lipozyme TL IM or by Rhizopus sp. lipases.


Assuntos
Fármacos Antiobesidade/análise , Ácidos Graxos Essenciais/análise , Lipídeos/análise , Azeite de Oliva/análise , Óleo de Brassica napus/análise , Óleo de Soja/análise , Fármacos Antiobesidade/química , Crambe (Planta)/química , Ácidos Graxos/análise , Ácidos Graxos/química , Ácidos Graxos Essenciais/química , Ácidos Graxos Insaturados/análise , Ácidos Graxos Insaturados/química , Lipídeos/química , Azeite de Oliva/química , Óleo de Brassica napus/química , Óleo de Soja/química
6.
Chem Phys Lipids ; 198: 1-9, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27087282

RESUMO

The crystallization behavior of lipids has important implications in industrial processing of food products, whose physical characteristics depend largely on crystallized fats. The study of the crystallization behavior and polymorphism of a pure lipid system is of great scientific importance as a means of gaining an understanding of the phenomena involved, serving as basic knowledge to help guide the addition or removal of these compounds in different raw materials. The crystallization behavior and polymorphism of pure tripalmitin (PPP) and tristearin (SSS) were investigated by Polarized Light Microscopy (PLM) and Differential Scanning Calorimetry (DSC) under different crystallization conditions. The polymorphic forms (ß' and ß) of PPP and SSS exhibited different morphologies depending on how they were obtained, either from α form recrystallization or from isotropic melt. Crystallization in the ß form was faster in SSS than in PPP, indicating that the process occurs faster in TAGs composed of longer fatty acid chains. Both ß' and ß polymorphic forms were obtained from α form recrystallization, albeit with predominance of the ß form.


Assuntos
Triglicerídeos/química , Cristalização , Microscopia , Modelos Moleculares , Conformação Molecular , Temperatura
7.
Mol Nutr Food Res ; 60(2): 420-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26548572

RESUMO

SCOPE: Emerging evidence indicates that the use of bioactive food components is a promising strategy to prevent the development of liver cancer. The goal of this study was to examine the chemopreventive effect of butyrate-containing structured lipids (STLs) produced by an enzymatic interesterification of tributyrin and flaxseed oil on rat hepatocarcinogenesis. METHODS AND RESULTS: Male Wistar rats were subjected to a classic "resistant hepatocyte" model of liver carcinogenesis and treated with STLs, tributyrin or flaxseed oil during the initial phases of hepatocarcinogenesis. Treatment with STLs and tributyrin strongly inhibited the development of preneoplastic liver lesions. The chemopreventive activity of tributyrin was associated with the induction of apoptosis and reduction of the expression of major activated hepatocarcinogenesis-related oncogenes. Treatment with STLs caused substantially greater inhibitory effects than tributyrin on oncogene expression. CONCLUSION: These results demonstrate that the tumor-suppressing activity of butyrate-containing STLs is associated with its ability to prevent and inhibit activation of major hepatocarcinogenesis-related oncogenes. Enrichment of histone H3K9me3 and H3K27me3 at the promoter of Myc and Ccnd1 genes may be related to the inhibitory effect on oncogene expression in the livers of STL-treated rats.


Assuntos
Anticarcinógenos/farmacologia , Ácido Butírico/farmacologia , Neoplasias Hepáticas Experimentais/prevenção & controle , Animais , Anticarcinógenos/química , Ácido Butírico/química , Regulação da Expressão Gênica/efeitos dos fármacos , Histonas/genética , Histonas/metabolismo , Óleo de Semente do Linho/química , Lipídeos/química , Lipídeos/farmacologia , Neoplasias Hepáticas Experimentais/patologia , Masculino , Oncogenes , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/prevenção & controle , Ratos Wistar , Triglicerídeos/química , Triglicerídeos/farmacologia
8.
Braz. j. pharm. sci ; 51(2): 415-427, Apr.-June 2015. tab, ilus
Artigo em Inglês | LILACS | ID: lil-755068

RESUMO

Two oil blends (sunflower/canola oils 85/15 (BL1) and canola/linseed oils 70/30 (BL2)), were prepared and enzymatically interesterified to be applied to surgically-induced wounds in rats. Following surgery, the animals were submitted to the Treatment with Physiological Saline (TPS) (control group), Blends (TBL), and Structured Lipids (TSL). The control group (TPS) received physiological saline solution for 15 days. In TBL, BL1 was administered during the inflammation phase (days 0-3) and BL2 in the tissue formation and remodeling phase (days 4-15). In TSL, Structured Lipid 1 (SL1) and Structured Lipid 2 (SL2) were used instead of BL1 and BL2, respectively. The aim of this study was to compare wound closure evolution among rats treated with the blends or structured lipids versus control rats treated with physiological saline. The wound healing process was evaluated by measuring the wound areas along the treatments and the concentrations of cytokines. An increase in the areas of wounds treated with the blends and structured lipids in the inflammatory phase was observed, followed by a steeper closure curve compared to wounds treated with physiological saline. The changes observed during the inflammatory phase suggest a potential therapeutic application in cutaneous wound healing which should be further investigated...


Duas misturas de óleos vegetais (girassol/canola 85/15 (BL1) e canola/linhaça, 70/30 (BL2) foram preparadas e interesterificadas por via enzimática para serem aplicadas em feridas induzidas cirurgicamente em ratos. Após a cirurgia, os animais foram submetidos ao tratamento com soro fisiológico (TPS) (grupo controle), tratamento com as misturas (TBL) e tratamento com os lipídios estruturados (TSL). O grupo controle (TPS) recebeu soro fisiológico por 15 dias. Em TBL, BL1 foi administrada durante a fase de inflamação (dias 0-3) e BL2 na fase de formação de tecido e remodelação (dias 4-15). Em TSL, os lipídios estruturados SL1 e SL2 foram usados em vez de BL1 e BL2, respectivamente. O objetivo deste estudo foi avaliar a evolução do fechamento das feridas dos grupos de ratos tratados com as misturas ou lipídios estruturados em comparação com os ratos do grupo controle, tratados com soro fisiológico. O processo de cicatrização das feridas foi avaliado através da medição das áreas das feridas ao longo dos tratamentos e pela determinação das concentrações de citocinas. Observou-se aumento das áreas das feridas tratadas com as misturas e os lipídios estruturados na fase inflamatória, seguida por um fechamento acentuado de feridas comparado com o tratamento com solução salina. As mudanças observadas durante a fase inflamatória sugerem uma potencial aplicação terapêutica na cicatrização de feridas cutâneas, fazendo-se necessárias investigações posteriores...


Assuntos
Masculino , Ratos , Infecção dos Ferimentos/tratamento farmacológico , Óleos de Plantas/efeitos adversos , Óleos de Plantas/farmacologia , Análise de Variância , Cicatrização , Citocinas/análise
9.
São Paulo; s.n; 3 maio 2006. 164 p. ilus, tab, graf.
Tese em Português | LILACS | ID: lil-448692

RESUMO

Durante anos, a manteiga foi muito apreciada pelo consumidor, mas por conter grande quantidade de ácidos graxos saturados e colesterol, seu consumo tem diminuído. Recentemente, a descoberta dos malefícios causados pelos ácidos graxos trans presentes nas margarinas produzidas por hidrogenação parcial aumentou o interesse por métodos alternativos de modificação de lipídios. Assim, o objetivo deste trabalho foi desenvolver um lipídio estruturado à base de gordura do leite que apresentasse maiores teores de ácidos graxos insaturados que a manteiga original e, consequentemente, melhor espalhabilidade, além de conter fitosteróis, constituindo a base de um alimento funcional com capacidade de reduzir os níveis de colesterol no sangue. Foram realizadas misturas da gordura do leite (GL) com óleo de girassol (OG) e ésteres de fitosteróis (EF) e foi efetuada interesterificação química e enzimática. As misturas e os lipídios estruturados obtidos foram analisados quanto a composição em ácidos graxos, consistência, conteúdo de gordura sólida (CGS), cinética de cristalização e estrutura cristalina, entre outras propriedades físico-químicas. Foram obtidos produtos contendo cerca de 60% de ácidos graxos insaturados pela adição de até 40% de OG e 25% de EF à gordura do leite, que originalmente possuía cerca de 33% de ácidos graxos insaturados. A interesterificação química melhorou a plasticidade das misturas, enquanto que a modificação enzimática não modificou de maneira expressiva sua consistência. A adição de pequenas quantidades de OG à GL provocou grande diminuição de sua consistência, enquanto que a diminuição do CGS ocorreu em proporções semelhantes às esperadas por interpolação linear. A edição de vídeos que permitam a observação da formação da estrutura cristalina de gorduras mostrou ser uma ferramenta de grande utilidade no estudo da cristalização de óleos e gorduras...


Assuntos
Tecnologia de Alimentos , Gorduras/análise , Lipídeos/análise , Margarina , Leite , Fitosteróis , Ácidos Graxos/análise , Análise de Alimentos
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