MTHFR 677C>T (rsRS1801133) variant is associated with hyperhomocysteinemia but not with clinical severity in patients with peripheral arterial disease / A variante MTHFR 677C>T (RS1801133) está associada a hiperhomocisteinemia, mas não a gravidade clínica em pacientes com doença arterial periférica

Abstract Background The MTHFR 677C>T variant's involvement with hyperhomocysteinemia and peripheral arterial disease (PAD) is still unclear. Objectives To evaluate associations between the MTHFR 677C>T (rs1801133) variant and susceptibility to and severity of PAD and homocysteine (Hcy) levels. Methods The study enrolled 157 PAD patients and 113 unrelated controls. PAD severity and anatomoradiological categories were assessed using the Fontaine classification and the Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC), respectively. The variant was genotyped using real-time polymerase chain reaction and Hcy levels were determined using chemiluminescence microparticle assay. Results The sample of PAD patients comprised 60 (38.2%) females and 97 (61.8%) males. Patients were older and had higher Hcy than controls (median age of 69 vs. 45 years, p<0.001; and 13.66 µmol/L vs. 9.91 µmol/L, p=0.020, respectively). Hcy levels and the MTHFR 677C>T variant did not differ according to Fontaine or TASC categories. However, Hcy was higher in patients with the CT+TT genotypes than in those with the CC genotype (14.60 µmol/L vs. 12.94 µmol/L, p=0.008). Moreover, patients with the TT genotype had higher Hcy than those with the CC+CT genotypes (16.40 µmol/L vs. 13.22 µmol/L, p=0.019), independently of the major confounding variables. Conclusions The T allele of MTHFR 677C>T variant was associated with higher Hcy levels in PAD patients, but not in controls, suggesting a possible interaction between the MTHFR 677C>T variant and other genetic, epigenetic, or environmental factors associated with PAD, affecting modulation of Hcy metabolism.

Resumo Contexto O envolvimento da variante MTHFR 677C>T na hiperhomocisteinemia e na doença arterial periférica (DAP) ainda não está claro. Objetivos Avaliar a associação da variante MTHFR 677C>T (rs1801133) com suscetibilidade e gravidade da DAP e valores séricos de homocisteína (Hcy). Métodos Este estudo caso-controle envolveu 157 pacientes com DAP e 113 controles não relacionados. A gravidade e as categorias anatomorradiológicas da DAP foram avaliadas pela classificação de Fontaine e pelo Inter-Society Consensus for the Management of Peripheral Arterial Disease, respectivamente. A genotipagem foi realizada por meio de reação em cadeia da polimerase em tempo real, e os valores de Hcy foram determinados por ensaio de micropartículas de quimioluminescência. Resultados Entre os pacientes com DAP, 97 (61,8%) eram homens e 60 (38,2%) eram mulheres, com mediana de idade de 69 anos. Os pacientes com DAP eram mais velhos e apresentaram valores mais elevados de Hcy do que os controles (mediana de 69 vs. 45 anos de idade, p < 0,001; 13,66 µmol/L vs. 9,91 µmol/L, p = 0,020, respectivamente). Os valores de Hcy foram mais elevados em pacientes com os genótipos CT+TT do que aqueles com o genótipo CC (14,60 µmol/L vs. 12,94 µmol/L, p = 0,008). Além disso, os pacientes com o genótipo TT apresentaram valores mais elevados de Hcy do que aqueles com os genótipos CC+CT (16,40 µmol/L vs. 13,22 µmol/L, p = 0,019, respectivamente), independentemente das principais variáveis confundidoras. Conclusões O alelo T da variante MTHFR 677C>T foi associado a valores mais elevados de Hcy nos pacientes com DAP, mas não em controles, sugerindo uma possível interação entre a variante genética MTHFR 677C>T e outros fatores genéticos, epigenéticos ou ambientais associados com a DAP na modulação do metabolismo da Hcy.

FOXP3 variants are independently associated with transforming growth factor B1 plasma levels in female patients with inflammatory bowel disease

Abstract Objective: The aim of this study was to evaluate the association of -924 G>A (rs2232365) and -3279 C>A (rs3761548) FOXP3 variants with IBD susceptibility, clinical and endoscopic activity, and IL-10 and TGF-β1 plasma levels. Method: The study included 110 IBD female patients, 60 with Ulcerative Colitis (UC) and 50 with Crohn's Disease (CD), and 154 female controls. FOXP3 variants were determined with Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP). Plasma levels of IL-10 and TGF-β1 were determined using immuno-fluorimetric assay. Results: AA genotype of rs2232365 and rs3761548 was associated with CD (OR = 3.147, 95% CI 1.015-9.758, p = 0.047) and UC (OR = 3.221, 95% CI 1.050-9.876, p = 0.041) susceptibility, respectively. However, were not associated with TGF-β1 and IL-10 levels, and endoscopic/clinical activity disease. GAGA haplotype was associated with IBD (OR = 4.003, 95% CI 1.100-14.56, p = 0.035) and UC susceptibility (OR = 6.107, 95% CI 1.609-23.18, p = 0.008). In addition, IBD patients with the GAGA haplotype had lower TGF-β1 levels (p = 0.041). Moreover, G/C haplotype (dominant model) had a protective effect of 60% in CD susceptibility and lower Endoscopic Severity Index. Conclusions: These results suggest that FOXP3 variants could exert a role in the Treg, which could be one of the factors involved in the susceptibility and pathogenesis of IBD.

Metabolic syndrome components are associated with oxidative stress in overweight and obese patients

ABSTRACT Objective: The aim of this study is to evaluate the influence of the body mass index (BMI) and the metabolic syndrome (MetS) parameters on oxidative and nitrosative stress in overweight and obese subjects. Subjects and methods: Individuals were divided into three groups: the control group (G1, n = 131) with a BMI between 20 and 24.9 kg/m2, the overweight group (G2, n = 120) with a BMI between 25 and 29.9 kg/m2 and the obese group (G3, n = 79) with a BMI ≥ 30 kg/m2. Results: G3 presented higher advanced oxidation protein products (AOPPs) in relation to G1 and G2 (p = 0.001 and p = 0.011, respectively) whereas G2 and G3 had lower levels of nitric oxide (NO) (p = 0.009 and p = 0.048, respectively) compared to G1. Adjusted for the presence of MetS to evaluate its influence, the levels of AOPPs did not differ between the groups, whereas NO remained significantly lower. Data adjusted by the BMI showed that subjects with higher triacylglycerol levels had higher AOPPs (p = 0.001) and decreased total radical-trapping antioxidant parameter/uric Acid (p = 0.036). Subjects with lower high-density lipoprotein (HDL) levels and patients with higher blood pressure showed increased AOPPs (p = 0.001 and p = 0.034, respectively) and lower NO levels (p = 0.017 and p = 0.043, respectively). Subjects who presented insulin resistance had higher AOPPs (p = 0.024). Conclusions: Nitrosative stress was related to BMI, and protein oxidation and nitrosative stress were related to metabolic changes and hypertension. MetS components were essential participants in oxidative and nitrosative stress in overweight and obese subjects.

The impact of cranberry (Vaccinium macrocarpon) and cranberry products on each component of the metabolic syndrome: a review

BACKGROUND: Some studies have shown that cranberry (Vaccinium macrocarpon) has beneficial effects on the components of the metabolic syndrome (MetS), a condition characterized by a cluster of cardiovascular risk factors suchas central obesity, hypertension, impaired glucose homeostasis, elevated triglycerides, and decreased HDL cholesterol levels. Cranberry is very rich in polyphenols, which may significantly reduce cardiovascular disease (CVD) risk. Main body of the ABSTRACT: Nutritional intervention studies have indicated that the intake of cranberries and cranberry products may have the following impact on metabolic health: (1) attenuate markers of obesity such as body weight, body mass index, and waist circumference; (2) reduce systolic and diastolic pressures; (3) decrease plasma concentrations of triglycerides and oxidized LDL-cholesterol, as well as increase HDL cholesterol; and (4) promote glucose homeostasis. In addition, nutritional intervention with cranberries could confer antioxidant and anti-inflammatory properties and the ability to reduce biomarkers of atherosclerosis associated with the MetS, such as homocysteine. Short CONCLUSION: Although there has been promising results, particularly related to lipid profile and blood pressure, further research is needed to support the recommendation of cranberry intake as a nutritional intervention for the treatment of MetS

n-3 polyunsaturated fatty acids supplementation in psoriasis: a review

Psoriasis is an immune mediated chronic inflammatory disease of unknown etiology and characterized by epidermal hyperplasia and inappropriate immune activation, which affects the skin and joints as well.The immunopathogenesis of psoriasis involves changes in the innate and acquired (T lymphocytes) immune system. The cells of the innate immune system when activated produce growth factors, cytokines, and chemokines that act on cells of the acquired immune system and vice versa, being characterized as atype 1 immune response disease. Fish oil n-3 polyunsaturated fatty acids, mainly eicosapentaenoic (EPA), and docosahexaenoic acids (DHA), reduce symptoms in many inflammatory skin diseases. The mechanism of action of fish oil in the treatment of psoriasis is widely based on the alteration of epidermal and blood cell membrane lipid composition. In the present study, we performed a review of the several studies, which analyzed the action of n-3 polyunsaturated fatty acids in patients with psoriasis. Taken together, the majority of the studies showed that n-3 polyunsaturated fatty acids, mainly from marine origin, have beneficial effects and can be utilized as adjuvant therapy in psoriasis treatment. Both oral and intravenous administration of fish oil n-3 polyunsaturated fatty acids had positive effects. However, further studies are warranted to answer many intriguing questions, for instance, the ideal quantity of fish oil to be utilized, the effect on different forms and severity of psoriasis and last, but not least, the consequences of using fish oil n-3 polyunsaturated fatty acids on the cardiovascular features of patients with psoriasis.

Associação entre deficiência de vitamina D, adiposidade e exposição solar em participantes do sistema de hipertensão arterial e diabetes melito / Association between vitamin D deficiency, adiposity and solar exposure in participants with arterial hypertension and diabetes mellitus

Atualmente, diversos estudos demonstram uma relação entre deficiência de vitamina D e diabetes melito tipo 2, obesidade e hipertensão arterial. A principal causa de deficiência de vitamina D é a falta de exposição solar adequada. O objetivo deste estudo foi avaliar os níveis séricos de vitamina D e sua associação com ingestão de vitamina D, composição corporal e exposição solar em pacientes participantes do Sistema de Hipertensão e Diabetes da cidade de Cascavel, PR. Participaram 304 adultos e idosos, de ambos os sexos, e foram avaliados os dados demográficos e antropométricos, hábitos de vida, presença de doenças prévias, dietética e a dosagem de vitamina D sérica. Utilizou-se do teste qui quadrado para verificação de associação e aderência e o teste de Kruskal-Wallis para comparação de medianas entre as variáveis estudadas. Verificou-se deficiência sérica de 25-hidroxivitamina D [25(OH)D] (<20ng/mL) em 52,6%, excesso de peso em 73,4%, aumento na circunferência abdominal em 77,6% e na percentagem de gordura corporal em 95,6% dos pacientes. Não houve associação entre a ingestão e os níveis séricos de vitamina D. Houve associação significativa entre circunferência abdominal (p<0,05), hipertensão arterial (p>0,001) e exposição solar inadequada (p<0,001) com os diferentes níveis séricos de vitamina D. Os pacientes com níveis séricos desejáveis de vitamina D apresentaram menores valores de índice de massa corpórea (p<0,03), de circunferência abdominal (p<0,01) e maior tempo de exposição solar (p=0,01). Este estudo verificou uma alta frequência de hipovitaminose D, sendo esta, associada com a diminuição de exposição solar e com adiposidade.

Currently, several studies have shown a relationship between vitamin D deficiency and type 2 diabetes mellitus, obesity and hypertension. The major cause of vitamin D deficiency is the lack of adequate sun exposure. The objective of the study was to evaluate serum vitamin D level and to verify its association with vitamin D ingestion, body composition and solar exposure in patients participating in the Hypertension and Diabetes System in Cascavel, PR. A total of 304 adult and elder patients from both genders participated in the study. Demographic and anthropometric data, lifestyle, presence of previous diseases, dietary and serum levels of vitamin D were evaluated. We used the chi square test for association verification and compliance and the Kruskal-Wallis test to compare medians between variables. It was verified serum 25-hydroxyvitamin D (25(OH)D) deficiency (<20ng/mL) in 52.6%, overweight and obesity in 73.4%, increase in abdominal circumference in 77.6% and in body fatpercentage in 95.6% of the patients. There was no association between ingestion and serum vitamin D levels. Significant association was found between abdominal circumference (p<0.05), hypertension (p=0.0006) and inadequate solar exposure (p<0.001) with serum vitamin D different levels. There was a high frequency of hypovitaminosis D and association with lower solar exposure and adiposity.

Avaliação do consumo de uma baixa quantidade diária de soja no estresse oxidativo, no perfil lipídico e inflamatório e na resistência à insulina em pacientes com síndrome metabólica / Evaluation of the intake of a low daily amount of soybeans in oxidative stress, lipid and inflammatory profile, and insulin resistance in patients with metabolic syndrome

OBJETIVO: Estudos demonstram que o consumo regular de soja diminui o risco cardiovascular e de diabetes. No entanto, grande parte desses estudos preconiza a ingestão diária de 25 g ou mais de proteína de soja, quantidade essa considerada alta e não bem tolerada pelos pacientes. O objetivo deste trabalho foi avaliar o efeito do baixo consumo diário de soja no estresse oxidativo e nos componentes da síndrome metabólica (SM). SUJEITOS E MÉTODOS:Quarenta indivíduos com SM foram selecionados e alocados em dois grupos: grupo controle (n = 20) e grupo soja (n = 20), que consumiu diariamente 12,95 g de proteína de soja, durante 90 dias. RESULTADOS:Após o tratamento o grupo soja apresentou diminuição da glicemia de jejum e aumento nos níveis de HDL e adiponectina. CONCLUSÃO: O consumo de uma baixa quantidade de soja por 90 dias, além de bem tolerado pelos pacientes, foi capaz de melhorar vários parâmetros relacionados à fisiopatologia da SM.

OBJECTIVE:Studies show that regular consumption of soybeans reduces the risk of diabetes and cardiovascular diseases. However, most of these studies recommend daily intake of 25 g or more of soy protein, an amount considered high and not well tolerated by patients. The objective of this study was to assess the effect of low daily intake of soybeans in oxidative stress and in components of the metabolic syndrome (MS). SUBJECTS AND METHODS: Forty individuals with MS were selected and divided into two groups: control group (n = 20) and soybean-treated group (n = 20), which consumed 12.95 g of soy protein for 90 days. RESULTS: After the treatment, the soybean-treated group showed a decrease in fasting glucose and increase in serum HDL and adiponectin. CONCLUSION:Low intake of soy protein for 90 days, besides being well tolerated by the patients, was able to improve several parameters related to the pathophysiology of MS.

Nitric oxide enhancement and blood pressure decrease in patients with metabolic syndrome using soy protein or fish oil / Aumento de óxido nítrico e diminuição da pressão sanguínea em pacientes com síndrome metabólica em uso de proteína de soja ou óleo de peixe

OBJECTIVE: To verify the effects of fish oil and soy on nitric oxide (NO) and blood pressure in patients with metabolic syndrome (MS). SUBJECTS AND METHODS: Sixty women with MS were investigated in a parallel randomized design study. The first group maintained their usual diet; the second group received 25 g/day of soy; the third group received 3 g/day of n-3 fatty acids, and the fourth group the same amount previously cited of n-3 fatty acids and soy. RESULTS: Serum nitric oxide metabolites showed significant increase after 90 days in the fish oil and soy groups. Systolic pressure reduced after 45 days of treatment with fish oil, whereas diastolic pressure decreased significantly throughout the study in the soy group. CONCLUSIONS: NO increase and blood pressure reduction with fish oil or soy protein reinforce the importance of the influence of NO on blood pressure in patients with MS.

OBJETIVO: Verificar o efeito do óleo de peixe e soja sobre o óxido nítrico (NO) e a pressão arterial em pacientes com síndrome metabólica (SM). SUJEITOS E MÉTODOS: Sessenta mulheres com SM foram avaliadas em estudo paralelo randomizado. O primeiro grupo manteve sua dieta habitual, o segundo grupo recebeu 25 g/dia de soja, o terceiro grupo recebeu 3 g/dia de ácidos graxos n-3 e o quarto grupo, a mesma quantidade citada anteriormente de ácidos graxos n-3 e soja. RESULTADOS: Os níveis séricos de metabólitos de NO foram significativamente superiores após 90 dias de intervenção com soja ou óleo de peixe. Somente o grupo que recebeu o óleo de peixe apresentou redução na pressão sistólica após 45 dias. Já a soja reduziu a pressão diastólica em 45 e 90 dias. CONCLUSÕES: O aumento de NO e a redução da pressão arterial com óleo de peixe ou proteína de soja reforçam a influência do óxido nítrico sobre a pressão arterial em pacientes com SM.

Efeito dos ácidos graxos n-3 no perfil glicêmico e lipídico, no estresse oxidativo e na capacidade antioxidante total de pacientes com síndrome metabólica / Effect of n-3 fatty acids in glycemic and lipid profiles, oxidative stress and total antioxidant capacity in patients with the metabolic syndrome

OBJETIVO: A síndrome metabólica (SM) é um conjunto de fatores que favorecem o desenvolvimento de doenças cardiovasculares. Estudos prévios demonstram que os ácidos graxos poliinsaturados (PUFAs) podem melhorar alguns desses fatores. O objetivo foi avaliar o efeito do óleo de peixe rico em PUFAs nos perfis glicêmico e lipídico, no estresse oxidativo e na capacidade antioxidante total (TRAP) no plasma em pacientes com SM. SUJEITOS E MÉTODOS: Foi realizado um ensaio clínico em 40 pacientes com SM (20 controles e 20 pacientes que consumiram 3 g/dia de PUFAs). RESULTADOS: O grupo que recebeu tratamento apresentou redução significativa nos níveis de triacilgliceróis e aumento no TRAP, mas sofreu aumento nos níveis de LDL, glicose e na resistência à insulina. CONCLUSÃO: Conclui-se que a ingestão de óleo de peixe foi capaz de diminuir os níveis de triacilgliceróis e aumentar o TRAP de pacientes com SM, porém verificou-se aumento nos níveis de LDL e na resistência à insulina.

OBJECTIVE: Metabolic syndrome (MS) is a cluster of factors which favors the development of cardiovascular diseases. Previous studies have shown that polyunsaturated fatty acids (PUFAs) can improve some of these factors. This study aimed to evaluate the effect of fish oil on glucose and lipid profiles, oxidative stress and total antioxidant capacity (TRAP) in patients with MS. SUBJECTS AND METHODS: We conducted a clinical trial in 40 patients with the MS (20 controls and 20 patients receiving 3 g/day of PUFAs). SUBJECTS AND RESULTS: The group that received treatment showed a significant decrease in levels of triglycerides and increased in TRAP, but they had a significant increase in LDL, glucose and insulin resistance. CONCLUSION: We conclude that intake of fish oil resulted in decreased levels of triglycerides and increased the TRAP of patients with MS; however, increased LDL levels and insulin resistance, were observed.

Estresse oxidativo em eritrócitos submetidos a 2, 2-azobis amidinopropano (aaph): efeito antioxidante e anti-hemolítico do chá verde (camellia sinensis) / Oxidative stress in erythrocytes submitted to 2, 2-azobis amidinopropane (aaph): antioxidant effect and anti-hemolytic effects of green tea (camellia sinensis)

O chá verde (Camellia sinensis) é uma bebida, bastante consumida pelos orientais, cuja composição apresenta as catequinas, polifenóis que possuem atividade antioxidante, quimioprotetora, antiinflamatória e anti-carcinogênica. Vários estudos têm demonstrado que o chá verde pode prevenir várias doenças associadas ao estresse oxidativo, tais como o câncer, doenças cardiovasculares e neurodegenerativas. Estes efeitos benéficos dependerão da quantidade de chá consumida e da biodisponibilidade das catequinas. O objetivo deste estudo foi avaliar a ação do extrato do chá verde (ECV) na inibição da hemólise oxidativa induzida pelo 2,2 azobis amidinopropano (AAPH). Este composto é um gerador de radicais livres que, a 37°C e ao abrigo da luz, gera radicais do tipo peroxil a uma taxa constante. Hemácias humanas de doadores saudáveis foram submetidas à AAPH e ao extrato de chá verde em diferentes concentrações. Os resultados indicam que o chá verde, na concentração de 0,54 mg/Ml, é um ótimo antioxidante e anti-hemolítico, inibindo em 81,6% a hemólise oxidativa de hemácias tratadas com AAPH. A ação antioxidante durou até 5 horas após a exposição das hemácias aos radicais livres gerados pelo AAPH, sendo que o chá verde, por si só, não levou a nenhuma lesão as hemácias. Nossos dados demonstram, pela primeira vez, que o chá verde pode inibir a hemólise oxidativa de eritrócitos humanos. Ensaios clínicos são necessários para investigar os possíveis benefícios do uso do chá verde como adjuvante terapêutico em doenças hemolíticas que envolvam a ação de radicais livres

Green tea (Camellia sinensis) is one of the most often consumed drinks by the Oriental and its components such as Cathechin, Polyphenols have antioxidant, chemoprotective, anti-inflammatory and anti-carcinogenic activities. Several studies have demonstrated that green tea is capable of preventing diseases associated with oxidative stress, such as cancer, cardiovascular and neurodegenerative diseases. These beneficial effects will depend on the quantity of green tea consumed and the bioavailability of the cathechins. The aim of this study was to assess the effect of the green tea extract (GTE) on the inhibition of oxidant hemolysis induced by 2.2 azobis amidinopropane (AAPH). This component generates free radicals which, at 37°C and daylight sheltered, may generate the type of radical called peroxil at a fairly constant rate. Red blood cells from healthy donors were submitted to the AAPH and to the green tea extract at different levels of concentration. The results indicated that in a concentration of 0.54 mg/mL works as an excellent antioxidant inhibiting 81.6 % of hemolysis in red blood cells with AAPH. The antioxidant activity lasted for 5 hours after exposing red blood cells to the free-radical generated by AAPH, and it must be said that green tea alone did not cause any lesion to red blood cells. It is the first time that our data shows that green tea may inhibit oxidant hemolysis in human erythrocyte. Clinical trials are necessary in order to find out the possible benefits of the use of green tea as a therapeutical adjuvant for hemolytic diseases involving the action of the free-radicals

Importância da ingestão de soja nos sintomas do climatério, osteoporose e doenças cardiovasculares / The importance of soy ingestion in postmenopausal symptoms, osteoporosis, and cardiovascular diseases

A soja é um alimento consumido especialmente por orientais e seu consumo data de pelo menos 5.000 anos. Os grãos de soja são ricos em proteínas e em fitoestrógenos, as isoflavonas, e seu consumo tem sido implicado na prevenção de doenças. Estudos epidemiológicos demonstraram que, em países orientais, a taxa de morbidade e mortalidade para doenças cardiovasculares, diabetes e câncer é menor do que a dos países ocidentais. Outro fato que merece ser salientado é que mulheres orientais, na menopausa, queixam-se muito menos dos sintomas do climatério do que as ocidentais. Estes resultados parecem ser devido ao maior consumo de soja por aquela população. Esta revisão examina as evidências e os possíveis mecanismos envolvidos entre o consumo de soja, a melhora dos sintomas do climatério e a prevenção de doenças cardiovasculares e metabólicas. Os sintomas do climatério, como, por exemplo, os fogachos e o aumento da incidência de osteoporose, são atenuados com o consumo da soja. As isoflavonas, além de sua ação hipoglicêmica, têm sido implicadas na prevenção de doenças cardiovasculares, por melhorarem o perfil lipídico dos pacientes. Com relação aos biomarcadores e citocinas inflamatórias, apesar de incipientes, os resultados das pesquisas são promissores. Por outro lado, o metabolismo de ferro parece ser afetado pelo seu consumo. Embora ainda existam alguns resultados contraditórios quanto ao consumo de soja, esta é indicada a todos que desejam ter uma alimentação saudável, realizar um tratamento natural para os sintomas do climatério e, ao mesmo tempo, prevenir doenças metabólicas.

Soy based products are consumed by oriental people for more than 5000 years. Soy grains are rich in proteins and phytoestrogens, the isofl avones, and soy consume have been implicated in disease prevention. Epidemiological studies have shown that cardiovascular disease, diabetes and cancer present higher morbidity and mortality in occidental than oriental countries. Another issue that deserves consideration is that oriental pos menopausal women are less symptomatic than the occidental ones, and soy ingestion seems to be an important cause. This review analyses the evidences and possible mechanisms evolved in the action of soy and its relationship with postmenopausal symptoms, cardiovascular and metabolic diseases. Isofl avones, besides a hypoglycemic action, have been implicated in the prevention of cardiovascular disease by improving lipid profi le. Infl ammatory biomarkers and cytokines research, although incipient, show promising results. On the other hand, iron metabolism seems to be negatively affected by soy ingestion. In spite of some contradictory results, long term ingestion of soy based products seems an appropriate measure to all persons who wish to consume a healthy food diet, proportioning a natural treatment of postmenopausal symptoms and the prevention of cardiovascular diseases.

Efeitos e mecanismos de ação dos ácidos graxos poliinsaturados n-3 na prevenção de doenças cardiovasculares / Mechanisms of action of polyunsaturated n-3 fatty acids for cardiovascular disease prevention

A ingestão de óleo de peixe tem demonstrado efeitos benéficos na prevenção das doenças cardiovasculares (DCV) e este efeito está relacionado à presença de ácidos graxos poliinsaturados n-3, em especial dos ácidos eicosapentaenóico (EPA, C20:5n-3) e docosahexaenóico (DHA, C22:6n-3), encontrados nos óleos de peixes de águas frias e profundas como salmão, arenque, atum e sardinhas. Estes compostos têm demonstrado importante ação antilipêmica, antiinflamatória, antitrombótica, antiarrítimica, anti-hipertensiva, entre outras. A ingestão de óleo de peixe em pacientes com doença cardíaca isquêmica e hiperlipoproteinemia diminuiu os níveis séricos de fibrinogênio, a viscosidade plasmática e a resistência vascular periférica total. Eles também atuam ajudando a manter a elasticidade da parede das artérias, impedindo a coagulação do sangue, reduzindo a pressão sangüínea e estabilizando a arritmia cardíaca. O seu principal efeito nas doenças coronárias é a redução da produção de tromboxana A2, agregante plaquetário que favorece a trombose. Outra ação destes compostos é a redução nos níveis de triacilgliceróis e da lipoproteína de densidade muito baixa (VLDL), porém com aumento da lipoproteína de baixa densidade (LDL). O aumento da LDL com redução da VLDL parece estar relacionado com a conversão da VLDL em LDL ou à redução na atividade do receptor de LDL. O EPA e o DHA modulam a resposta inflamatória, atuando na diminuição da transcrição de citocinas pró-inflamatórias e na expressão de moléculas de adesão na superfície vascular. Este estudo propõe-se a revisar os principais mecanismos envolvidos na prevenção de DCV pelos ácidos graxos n-3.

Fish oil ingestion has shown beneficial effects for cardiovascular disease (CVD) prevention, and this effect is related to the polyunsaturated fatty acids, specially eicosapentaenoic (EPA, C20:5n-3) and docosahexaenoic (DHA, C22:6n-3), found in fish from cold and deep water, such as salmon, tune and sardine. These compounds have important antilipidemic, antiinflammatory, antithrombotic, antiarrhytmic, and antihypertensive action. Fish oil ingestion in patients with ischemic heart disease and hyperlipoproteinemia decreased fibrinogen serum levels, plasmatic viscosity and total peripheral resistance. They also act by helping to maintain artery wall elasticity, preventing blood coagulation, reducing blood pressure and preventing fatal cardiac arrhythmias. Their major effect in coronary disease isthe decrease production of thromboxane A2, platelet aggregant that favors thrombosis; another effect is the reduction of tryacylglicerol levels and very low density lipoprotein (VLDL), although with low density lipoprotein (LDL) increase. This increment seems related to the conversion of VLDL in LDL or to the decreased activity of LDL receptor. EPA and DHA modulate inflammatory reaction through the reduction of pro-inflammatory cytokines transcription and adhesion molecules expression on the vascular surface. This review proposes to study the main mechanisms evolved in CVD prevention by n-3 polyunsaturated fatty acids.