Tags

Type your tag names separated by a space and hit enter

Hyperhomocysteinemia and endothelial function in young subjects: effects of vitamin supplementation.
Clin Cardiol. 2002 Nov; 25(11):495-501.CC

Abstract

BACKGROUND

The relationship between hyperhomocysteinemia and cardiovascular disease has not been totally elucidated.

HYPOTHESIS

The study aimed to verify the association between hyperhomocysteinemia and endothelial dysfunction before and after modification of total homocysteine (tHcy) serum levels with vitamin supplementation in young male subjects devoid of any other cardiovascular risk factor.

METHODS

Twenty hyperhomocysteinemic (tHcy > 15 [micromol/l) male volunteers (< or = 40 years) and 20 age-matched subjects with normal tHcy levels (tHcy < 13 micromol/l) were included. Exclusion criteria were smoking, hypertension, diabetes, vitamin ingestion, obesity, hypercholesterolemia, renal failure, and positive antiphospholipid antibodies. Serum tHcy, folate, vitamin B12 levels, activated protein C and S, protein C resistance, fibrinogen, prothrombin, thrombin, antithrombin III, and in vitro oxidation of low-density lipoprotein (LDL) particles were measured. Noninvasive ultrasound measurements of endothelium-dependent (EDD) and -independent dilatation (EID) of the brachial artery were performed. Each pair was then randomly assigned to receive a vitamin capsule (0.6 mg folic acid, 0.8 mg B12. and 2.0 mg B6) oran identical placebo during 8 weeks, in a double-blind study design. After the treatment phase, blood samples and vascular reactivity were repeated.

RESULTS

Nine pairs of volunteers received vitamins and 11 received placebo. Hyperhomocysteinemic subjects had lower baseline serum levels of vitamin B12. Serum folate levels, antithrombotic function, in vitro LDL oxidation, and EDD were similar in all groups. After the vitamin supplementation, serum folic acid levels increased significantly both in normo- and hyperhomocysteinemic subjects, unlike vitamin B12, which increased only in the hyperhomocysteinemic individuals. Plasma tHcy decreased significantly in the supplemented groups. Treatment with vitamins was not associated with improvement in EDD or antithrombotic function.

CONCLUSIONS

Mild hyperhomocysteinemia is not associated with endothelial dysfunction in young male subjects with no additional cardiovascular risk factors, and reduction of tHcy by vitamin supplementation does not modify EDD in this age group. In this sample, tHcy was more related to vitamin B12 than to folic acid status.

Authors+Show Affiliations

Institute of Nutrition and Food Technology, University of Chile, Santiago. shirsch@uec.inta.uchile.clNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Clinical Trial
Journal Article
Randomized Controlled Trial
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

12430779

Citation

Hirsch, Sandra, et al. "Hyperhomocysteinemia and Endothelial Function in Young Subjects: Effects of Vitamin Supplementation." Clinical Cardiology, vol. 25, no. 11, 2002, pp. 495-501.
Hirsch S, Pia De la Maza M, Yañez P, et al. Hyperhomocysteinemia and endothelial function in young subjects: effects of vitamin supplementation. Clin Cardiol. 2002;25(11):495-501.
Hirsch, S., Pia De la Maza, M., Yañez, P., Glasinovic, A., Petermann, M., Barrera, G., Gattas, V., Escobar, E., & Bunout, D. (2002). Hyperhomocysteinemia and endothelial function in young subjects: effects of vitamin supplementation. Clinical Cardiology, 25(11), 495-501.
Hirsch S, et al. Hyperhomocysteinemia and Endothelial Function in Young Subjects: Effects of Vitamin Supplementation. Clin Cardiol. 2002;25(11):495-501. PubMed PMID: 12430779.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Hyperhomocysteinemia and endothelial function in young subjects: effects of vitamin supplementation. AU - Hirsch,Sandra, AU - Pia De la Maza,M, AU - Yañez,Paulina, AU - Glasinovic,Andrea, AU - Petermann,Margarita, AU - Barrera,Gladys, AU - Gattas,Vivian, AU - Escobar,Edgardo, AU - Bunout,Daniel, PY - 2002/11/15/pubmed PY - 2003/2/25/medline PY - 2002/11/15/entrez SP - 495 EP - 501 JF - Clinical cardiology JO - Clin Cardiol VL - 25 IS - 11 N2 - BACKGROUND: The relationship between hyperhomocysteinemia and cardiovascular disease has not been totally elucidated. HYPOTHESIS: The study aimed to verify the association between hyperhomocysteinemia and endothelial dysfunction before and after modification of total homocysteine (tHcy) serum levels with vitamin supplementation in young male subjects devoid of any other cardiovascular risk factor. METHODS: Twenty hyperhomocysteinemic (tHcy > 15 [micromol/l) male volunteers (< or = 40 years) and 20 age-matched subjects with normal tHcy levels (tHcy < 13 micromol/l) were included. Exclusion criteria were smoking, hypertension, diabetes, vitamin ingestion, obesity, hypercholesterolemia, renal failure, and positive antiphospholipid antibodies. Serum tHcy, folate, vitamin B12 levels, activated protein C and S, protein C resistance, fibrinogen, prothrombin, thrombin, antithrombin III, and in vitro oxidation of low-density lipoprotein (LDL) particles were measured. Noninvasive ultrasound measurements of endothelium-dependent (EDD) and -independent dilatation (EID) of the brachial artery were performed. Each pair was then randomly assigned to receive a vitamin capsule (0.6 mg folic acid, 0.8 mg B12. and 2.0 mg B6) oran identical placebo during 8 weeks, in a double-blind study design. After the treatment phase, blood samples and vascular reactivity were repeated. RESULTS: Nine pairs of volunteers received vitamins and 11 received placebo. Hyperhomocysteinemic subjects had lower baseline serum levels of vitamin B12. Serum folate levels, antithrombotic function, in vitro LDL oxidation, and EDD were similar in all groups. After the vitamin supplementation, serum folic acid levels increased significantly both in normo- and hyperhomocysteinemic subjects, unlike vitamin B12, which increased only in the hyperhomocysteinemic individuals. Plasma tHcy decreased significantly in the supplemented groups. Treatment with vitamins was not associated with improvement in EDD or antithrombotic function. CONCLUSIONS: Mild hyperhomocysteinemia is not associated with endothelial dysfunction in young male subjects with no additional cardiovascular risk factors, and reduction of tHcy by vitamin supplementation does not modify EDD in this age group. In this sample, tHcy was more related to vitamin B12 than to folic acid status. SN - 0160-9289 UR - https://www.unboundmedicine.com/medline/citation/12430779/Hyperhomocysteinemia_and_endothelial_function_in_young_subjects:_effects_of_vitamin_supplementation_ DB - PRIME DP - Unbound Medicine ER -