5-methyltetrahydrofolate and Hypertension

Clarifying the association between 5-methyltetrahydrofolate and homocysteine and the effect pattern of methylene tetrahydrofolate reductase (MTHFR C677T) may contribute to the management of homocysteine and may serve as a significant reference for a randomized controlled trial of 5-methyltetrahydrofolate intervention. This study aimed to reveal the association between these two biochemical indices.. Study population was drawn from the baseline data of the China Stroke Primary Prevention Trial (CSPPT), including 2328 hypertensive participants. 5-methyltetrahydrofolate and homocysteine were determined by stable-isotope dilution liquid chromatography-tandem mass spectrometry and automatic clinical analyzers, respectively. MTHFR C677T polymorphisms were detected using TaqMan assay. Multiple linear regression was performed to evaluate the association between serum 5-methyltetrahydrofolate and homocysteine.. There was a significant inverse association between 5-methyltetrahydrofolate and homocysteine when 5-methyltetrahydrofolate was ≤ 10 ng/mL, and this association was modified by MTHFR C677T (per 1-ng/mL increment; All: β = - 0.50, P <  0.001; CC: β = - 0.14, P = 0.087; CT: β = - 0.20, P = 0.011; TT: β = - 1.19, P <  0.001). Moreover, the decline in trend in genotype TT participants was stronger than in genotype CC participants (P for difference <  0.001) and genotype CT participants (P for difference <  0.001), while there was no significant difference between genotype CC and genotype CT participants (P for difference = 0.757).. Our data showed a non-linear association between serum homocysteine and 5-methyltetrahydrofolate among Chinese hypertensive adults, however, it could be inversely linearly fitted when serum 5-methyltetrahydrofolate was ≤ 10 ng/mL, and this association was modified by MTHFR C677T.

Topics: Adult; Cross-Sectional Studies; Genotype; Homocysteine; Humans; Hypertension; Methylenetetrahydrofolate Reductase (NADPH2); Tetrahydrofolates

Certain epidemiological and experimental studies suggest that n-3 fatty acids and folate can reduce blood pressure (BP). We investigated the effect of a daily supplementation with dietary doses of B-vitamins or n-3 fatty acids for 5 years on BP in patients with a history of CVD who participated in the Supplémentation en Folates et Omega-3 trial. The patients (n 2501; 1987 men and 514 women) were randomly assigned in a 2 × 2 factorial design to one of four groups: B-vitamins (5-methyl-THF (560 μg); vitamin B₆ (3 mg) and vitamin B₁₂ (20 μg)) and a placebo capsule for n-3 fatty acids; n-3 fatty acids (600 mg of EPA and DHA at a ratio of 2:1) and a placebo capsule for B-vitamins; both B-vitamins and n-3 fatty acids; or placebo capsules for both treatments. The patients took two capsules daily in a double-blind manner for a median duration of 4·7 years. At baseline and annual examination for 5 years, the patients underwent a clinical examination where BP and clinical and biological parameters were assessed. No effect of supplementation with either n-3 PUFA or B-vitamins on BP was observed in crude and adjusted multivariate models. Change in BP was not associated with change in homocysteine. In conclusion, the present results do not support the routine use of dietary supplements containing B-vitamins, or of n-3 fatty acids, to reduce BP in people with prior CVD.

Topics: Adult; Aged; Aged, 80 and over; Antihypertensive Agents; Blood Pressure; Body Mass Index; Cardiovascular Diseases; Cohort Studies; Dietary Supplements; Double-Blind Method; Fatty Acids, Omega-3; Female; Follow-Up Studies; Homocysteine; Humans; Hypertension; Male; Middle Aged; Overweight; Patient Compliance; Tetrahydrofolates; Vitamin B Complex

Hyperhomocysteinaemia and other risk factors associated with blood pressure have been reported in large community-based studies in different populations. However, it is not fully established whether hypertension is associated with high plasma total homocysteine levels (tHcy) or components of the homocysteine re-methylation pathway including vitamin B(12), plasma 5-methyltetrahydrofolate (5-MTHF) or red blood cell (RBC) 5-MTHF.. In this study we tested the hypothesis that RBC 5-MTHF could be a marker for long-term folate status in the blood and low RBC 5-MTHF may be associated with hypertension.. This was a cross-sectional study in a community-based setting and 492 males and 431 females were investigated. Systolic and diastolic blood pressures were determined and fasting blood samples were taken for determination of plasma tHcy, creatinine, uric acid, lipids, plasma 5-MTHF, RBC 5-MTHF and vitamin B(12).. In males, the risk of hypertension was significantly (95% CI 1.9, 8.7; p = 0.003) increased by 1.8-fold in the first quartile compared with the highest quartile of RBC 5-MTHF when adjusted for body mass index (BMI), age, dyslipidaemia, uric acid, creatinine, smoking, plasma tHcy and vitamin B(12). The risk of hypertension was also significantly increased (95% CI 1.1, 9.2; p = 0.03) by 1.1-fold in the highest quartile compared with the lowest quartile of plasma tHcy when adjusted for BMI, age, dyslipidaemia, uric acid, creatinine, smoking, plasma and RBC 5-MTHF and vitamin B(12). There were no associations of hypertension with plasma tHcy, and other components of the Hcy re-methylation pathway were observed in females.. The association between hypertension and low RBC 5-MTHF was stronger than any other components of the homocysteine re-methylation pathway. Results from this study suggest that folate measurements in RBC seem to be the most reliable marker indicating 5-MTHF deficiency and disturbances in the Hcy re-methylation pathway in association with hypertension.

Topics: Adult; Aged; Biomarkers; Blood Pressure; Chi-Square Distribution; Cross-Sectional Studies; Diastole; Down-Regulation; Erythrocytes; Fasting; Female; Humans; Hyperhomocysteinemia; Hypertension; Iran; Logistic Models; Male; Middle Aged; Multivariate Analysis; Odds Ratio; Risk Assessment; Risk Factors; Sex Factors; Systole; Tetrahydrofolates