Plasma total homocysteine response to oral doses of folic acid and pyridoxine hydrochloride (vitamin B6) in healthy individuals. Oral doses of vitamin B6reduce concentrations of serum folate

1999 ◽  
Vol 59 (2) ◽  
pp. 139-146 ◽  
Author(s):  
M. A. Mansoor ◽  
O. Kristensen ◽  
T. Hervig ◽  
C. J. Bates ◽  
K. Pentieva ◽  
...  
Keyword(s):  
Folic Acid ◽  
Vitamin B6 ◽  
Serum Folate ◽  
Healthy Individuals ◽  
Pyridoxine Hydrochloride ◽  
Total Homocysteine ◽  
Oral Doses ◽  
Plasma Total Homocysteine

scholarly journals Plasma Total Homocysteine, Folate, and Vitamin B12 Status and Hospitalizations for Cardiovascular Disease

Pteridines ◽  
2007 ◽  
Vol 18 (1) ◽  
pp. 122-127
Author(s):  
Bakhouche Houcher ◽  
Mirande Candito ◽  
Pierre Gibelin
Keyword(s):  
Vitamin B12 ◽  
Serum Vitamin ◽  
Inverse Correlation ◽  
Serum Folate ◽  
Plasma Thcy ◽  
Total Homocysteine ◽  
Group 2 ◽  
Folate And Vitamin B12 ◽  
Plasma Total Homocysteine ◽  
Group 1

Abstract Elevated plasma total homocysteine (tHcy) is an independent risk factor for cardiovascular disease (CVD). Also known is that plasma folate and vitamin B12 influence homocysteine metabolism as cosubstrate and cofactor, respectively. This population-based study was conducted to evaluate the plasma concentrations of tHcy, folate, and vitamin B12 in 54 older patients aged ≥51 years (40 males; 14 females) of Nice hospital cardiology service. After excluding cases with a serum creatinine >120 mmol/L, we established the test properties of a plasma tHcy concentration <15 μmol/L (Group 1) or ≥15 μmol/L (Group 2). In the population aged ≥51 years, plasma tHcy was higher in women (18.0 μmol/L) than in men (15.5 μmol/L; not significant), conversely, serum vitamin B12 was higher in men (376.9 pg/ml) than in women (340.7 pg/ml; not significant). Average plasma tHcy was 11.5 μmol/L in Group 1 and 21.6 μmol/L in Group 2. Vice versa, serum vitamin B12 was higher in Group 1 (419.5 pg/ml) than in Group 2 (307.2 pg/ml) (p <0.05). Correlation analysis (Pearson's r) in the total study population (20-84 years) indicated an inverse correlation between serum folate and age (r = -0.231, p <0.05). In the subjects, aged ≥51 years, there was a significant negative correlation between age and tHcy levels (r = -0.283, p <0.05) and serum vitamin B12 concentrations (r = -0.326, p <0.01) but not with serum folate. However, in subjects with tHcy <15 μmol/L, a significant inverse correlation existed between plasma tHcy and serum folate (r = -0.455; p <0.05). In conclusion, these results highlight the relevance of the vitamin status and particularly of folate levels in the modulation of fasting tHcy levels in the patients with clinical hyperhomocysteinemia, defined as plasma tHcy >15 μmol/L.

scholarly journals Detectable Unmetabolized Folic Acid, and Sufficient Folate and Vitamin B12 Concentrations Are Evident in Canadian Children with Sickle Cell Disease

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1100-1100
Author(s):  
Brock Williams ◽  
Heather McCartney ◽  
Yvonne Lamers ◽  
Suzanne Vercauteren ◽  
John Wu ◽  
...  
Keyword(s):  
Folic Acid ◽  
Sickle Cell Disease ◽  
Vitamin B12 ◽  
Sickle Cell ◽  
Vitamin B6 ◽  
Serum Folate ◽  
High Dose ◽  
Cell Disease ◽  
Median Serum ◽  
B Vitamin

Abstract Objectives Canadian children with sickle cell disease (SCD) are routinely supplemented with high-dose folic acid (1 mg/d), synthetic folate, due to increased erythrocyte production and turn-over in the disease. Folate also plays a vital role in one-carbon metabolism. Impairments in this folate-dependent mechanism can also occur due to secondary B-vitamin (vitamin B2, B6 and B12) deficiencies. The study objective was to determine B-vitamin status in Canadian children with SCD. Methods Serum and plasma samples from children diagnosed with SCD were obtained from BC Children's Hospital BioBank (Vancouver, Canada). Samples were analyzed for folate, vitamin B6, and related metabolites using electrospray ionization-liquid chromatography-tandem mass spectrometry. Vitamin B12 concentrations were analyzed using chemiluminescent immunoassay. World Health Organization cut-offs were used to determine deficiencies of folate (&lt;10 nmol/L) and vitamin B12 (&lt;150 pmol/L), and European Food Safety Authority Panel cut-offs were used for vitamin B6 (&lt;30 nmol/L pyridoxal 5’-phosphate; PLP). Medians with interquartile ranges (IQR) are presented. Results Six individuals (50% male; SCD type: Hgb SS n = 3, Hgb SC n = 2, HbSβ,0-Thal n = 1) were included. Median age of participants was 15 (9, 18) years. Half (50%) of participants were prescribed hydroxyurea (median dose: 21(14, 30) mg/kg/d), and all participants were prescribed 1 mg/d folic acid (adherence data not available). Median serum folate was 55.4 (43.1, 71.9) nmol/L, with levels 3 to 15 times above the cut-off for deficiency. Unmetabolized folic acid (UMFA), unused folic acid in circulation, was detected in all six participants. All participants were vitamin B12 sufficient, with median plasma vitamin B12 of 325 (288, 411) nmol/L. The majority (n = 5; 83%) had sufficient B6 status, with median serum PLP of 39 (36.9, 44.2) nmol/L. Conclusions In this pilot project, there was limited evidence of B-vitamin deficiencies among Canadian children with SCD. Serum folate levels exceeded the cut-off for deficiency by 3 to 15 times, with all participants having detectable levels of UMFA. A randomized clinical trial re-assessing the routine practice of high-dose folic acid supplementation in children with SCD is warranted. Funding Sources Thrasher Research Fund and Rare Disease Foundation.

scholarly journals Low-dose folic acid supplementation does not influence plasma methionine concentrations in young non-pregnant women

1999 ◽  
Vol 82 (2) ◽  
pp. 85-89 ◽  
Author(s):  
Ingeborg A. Brouwerv ◽  
Marijke van Dusseldorp ◽  
Marinus Duran ◽  
Chris M. G. Thomas ◽  
Joseph G. A. J. Hautvast ◽  
...  
Keyword(s):  
Folic Acid ◽  
Low Dose ◽  
Inverse Correlation ◽  
Folic Acid Supplementation ◽  
Vitamin B ◽  
Plasma Vitamin ◽  
Acid Supplementation ◽  
Erythrocyte Folate ◽  
Total Homocysteine ◽  
Plasma Total Homocysteine

An elevated plasma total homocysteine (tHcy) concentration is a risk factor for cardiovascular disease and for having offspring with a neural-tube defect. Folate is a methyl donor in the remethylation of homocysteine into methionine. Although folic acid supplementation decreases tHcy concentrations, effects of folic acid supplementation on plasma methionine concentrations are unclear. There is also concern that folic acid supplementation negatively affects vitamin B12 status. We studied effects of low-dose folic acid supplementation on methionine and vitamin B12 concentrations in plasma. We also investigated whether baseline plasma methionine and tHcy concentrations correlated with the baseline folate and vitamin B12 status. For a period of 4 weeks, 144 young women received either 500 μg folic acid each day, or 500 μg folic acid and placebo tablets on alternate days, or a placebo tablet each day. Plasma methionine, tHcy and plasma vitamin B12 concentrations were measured at start and end of the intervention period. Folic acid supplementation had no effect on plasma methionine or plasma vitamin B12 concentrations although it significantly decreased tHcy concentrations. Plasma methionine concentrations showed no correlation with either tHcy concentrations (Spearman rs - 0·01, P = 0·89), or any of the blood vitamin variables at baseline. Baseline tHcy concentrations showed a slight inverse correlation with baseline concentrations of plasma vitamin B12 (rs - 0·25, P < 0·001), plasma folate (rs - 0·24, P < 0·01) and erythrocyte folate (rs - 0·19, P < 0·05). In conclusion, low-dose folic acid supplementation did not influence plasma methionine or plasma vitamin B12 concentrations. Furthermore, no correlation between plasma methionine concentrations and the blood folate and vitamin B12 status was shown.

scholarly journals Gonadotropin treatment increases homocysteine levels in idiopathic hypogonadotropic hypogonadism: an indirect effect mediated by changes in body composition

2003 ◽  
Vol 179 (1) ◽  
pp. 35-39 ◽  
Author(s):  
C Oktenli ◽  
Z Yesilova ◽  
M Ozata ◽  
H Yaman ◽  
A Tuzun ◽  
...  
Keyword(s):  
Folic Acid ◽  
Hypogonadotropic Hypogonadism ◽  
Free Testosterone ◽  
Multivariate Regression Analysis ◽  
Idiopathic Hypogonadotropic Hypogonadism ◽  
Plasma Thcy ◽  
Total Homocysteine ◽  
Vitamin B 12 ◽  
Male Patients ◽  
Plasma Total Homocysteine

The main objective of the present study was to examine the alterations in plasma total homocysteine (tHcy) concentrations during a testosterone-deficient state and after gonadotropin treatment for 6 Months in patients with idiopathic hypogonadotropic hypogonadism (IHH). Thirty-five newly diagnosed male patients with IHH (mean age 21.34+/-1.53 years) and 29 age- and body mass index-matched healthy males (mean age 21.52+/-1.77 years) were recruited into the study. Pretreatment levels of free testosterone (1.51+/-0.66 pg/ml), estradiol (21.37+/- 4.37 pg/ml), FSH (0.91+/-0.24 IU/l) and LH (1.25+/- 0.53 IU/l) were lower than controls (25.17+/-3.06 pg/ml, 31.00+/-4.96 pg/ml, 3.14+/-1.62 IU/l and 4.83+/-1.65 IU/l respectively) (P<0.001). They increased significantly after treatment (18.18+/-1.59 pg/ml, 27.97+/- 4.25 pg/ml, 2.41+/-0.27 IU/l and 2.79+/-0.19 IU/l respectively) (P<0.001). Patients with IHH had lower tHcy levels than controls (10.14+/-1.34 and 12.58+/- 2.29 micro mol/l respectively) (P<0.001). Plasma tHcy concentrations increased significantly (12.63+/-1.44 micromol/l) after 6 months of treatment (P<0.001). As compared with the controls, pretreatment levels of serum creatinine (63.54+/-13.01 vs 82.84+/-16.69 micromol/l), hemoglobin (12.98+/-0.56 vs 13.83+/-0.71 g/dl) and hematocrit (39.29+/-2.01 vs 41.38+/-1.95%) were significantly lower (P<0.001), and they increased significantly following treatment (80.24+/-11.93 micromol/l, 13.75+/-0.49 g/dl and 41.26+/-1.78% respectively) (P<0.001). The pretreatment folic acid and vitamin B(12) levels were significantly higher in patients when compared with controls (14.87+/-5.68 vs 12.52+/-4.98 nmol/l, P=0.034 and 289.75+/-92.34 vs 237.59+/-108.17 pmol/l, P=0.002 respectively). They decreased significantly after treatment (11.29+/-3.31 nmol/l and 228.51+/-54.33 pmol/l respectively) (P<0.001). The univariate and multivariate regression analysis results showed that only changes in creatinine, creatinine clearance, vitamin B12 and folic acid were independently associated with changes in tHcy levels in patients with IHH. In conclusion, the increase in plasma tHcy concentrations following gonadotropin treatment seems to be largely independent of changes in androgen levels.

Evaluation of cardiovascular risk factors and related clinical markers in healthy young Japanese adults

2007 ◽  
Vol 45 (2) ◽  
Author(s):  
Chiaki Yagura ◽  
Noboru Takamura ◽  
Koichiro Kadota ◽  
Tatsuki Nagazumi ◽  
Yukiko Morishita ◽  
...  
Keyword(s):  
Young Adults ◽  
Intima Media Thickness ◽  
Carotid Intima Media Thickness ◽  
Serum Folate ◽  
Effective Prevention ◽  
Media Thickness ◽  
Japanese Adults ◽  
Total Homocysteine ◽  
Plasma Total Homocysteine ◽  
Age And Sex

Abstract: Since atherosclerosis is a slowly progressive process at a young age, effective preventive measures should be taken early in life to prevent future events associated with cardiovascular disease.: The study population comprised 132 young Japanese adults (mean age 21.4 years, range 18–31 years). We screened plasma total homocysteine and serum folate levels and evaluated mean carotid intima-media thickness and cardio-ankle vascular index.: Multiple regression analysis after adjustment for age and sex revealed that only folate levels were significantly correlated with plasma total homocysteine levels (β=–0.37, p=0.028). Carotid intima-media thickness adjusted for age and sex and compared between quintiles of total homocysteine levels was significantly increased in the highest quintile compared with other quintiles. Cardio-ankle vascular index increased with age in both women and men, but no additional determinants were identified in young adults.: Serum folate is an independent determinant of plasma total homocysteine levels, and mild hyperhomocysteinemia may represent a risk factor for increased carotid intima-media thickness, even in young adults. Comprehensive health education from the early period of life, including the suggestion of appropriate dietary measures, is important for effective prevention of future atherosclerosis.Clin Chem Lab Med 2007;45:220–5.

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