Effects of some pre-analytical conditions on the measurement of homocysteine and cysteine in plasma

2004 ◽  
Vol 42 (2) ◽  
Author(s):  
Maddalena L. Zighetti ◽  
Veena Chantarangkul ◽  
Rossana Lombardi ◽  
Anna Lecchi ◽  
Marco Cattaneo
Keyword(s):  
Venous Thrombosis ◽  
Room Temperature ◽  
Reliable Measurement ◽  
Blood Samples ◽  
Artifactual Changes ◽  
Total Homocysteine ◽  
Citrate Dextrose ◽  
Crushed Ice ◽  
Plasma Total Homocysteine

AbstractThe association of hyperhomocysteinemia and hypercysteinemia with the risk of arterial and venous thrombosis is well documented. While it is known that standardized pre-analytical conditions are necessary for reliable measurement of plasma total homocysteine, the effects of pre-analytical conditions on cysteine measurement are less well known. The aim of this study was to evaluate the effects of pre-analytical conditions on the measurement of homocysteine and cysteine. We observed that the concentration of total homocysteine in plasma increased significantly with time (38% after 6 h), whereas total cysteine decreased (5% after 2h) when blood anticoagulated with ethylenediaminetetraacetic tripotassium salt was kept at room temperature. These changes were minimized when acidic citrate dextrose was used as an anticoagulant and were abolished when blood samples were immediately placed on crushed ice, independently of the anticoagulant. Storage of plasma for 72h at room temperature induced a small (≅6%), but significant, decrease in cysteine when blood was collected in ethylenediaminetetraacetic tripotassium salt. In contrast, homocysteine was stable in plasma for 72h, independently of the anticoagulant used. In conclusion, if blood samples for plasma total homocysteine and cysteine measurement cannot be kept on ice, they should be collected in acidic citrate dextrose to minimize the artifactual changes.

scholarly journals Catechol-O-methyltransferase genotype is associated with plasma total homocysteine levels and may increase venous thrombosis risk

2007 ◽  
Vol 98 (12) ◽  
pp. 1226-1231 ◽  
Author(s):  
Sita Vermeulen ◽  
Ad Hermus ◽  
Henk Blom ◽  
Henkjan Gellekink ◽  
Jan-Willem Muntjewerff ◽  
...  
Keyword(s):  
Risk Factor ◽  
Venous Thrombosis ◽  
Haplotype Analysis ◽  
Case Control Study ◽  
Primary Objective ◽  
Thrombosis Risk ◽  
Total Homocysteine ◽  
Recurrent Venous Thrombosis ◽  
Plasma Total Homocysteine ◽  
Control Study

SummaryA disturbed methylation has been proposed as a mechanism via which homocysteine is associated with diseases like vascular disease, neural tube defects and mental disorders. Catechol- O-methyltransferase (COMT) is involved in the S-adenosylmethionine- dependent methylation of catecholamines and catecholestrogens and in this way contributes to homocysteine synthesis. COMT dysfunction has been related to schizophrenia and breast cancer. We hypothesized that COMT dysfunction by virtue of functional genetic polymorphisms may affect plasma total homocysteine (tHcy). Our primary objective was to study the association between common COMT polymorphisms and tHcy. Secondly, we evaluated these polymorphisms as a risk factor for recurrent venous thrombosis. We obtained genotype data from four polymorphisms in the COMT gene (rs2097603, rs4633, rs4680 [324G>A] and rs174699) from 401 populationbased controls. We performed haplotype analysis to investigate the association between common haplotypes and tHcy. In addition, we assessed the rs4680 variant as a genetic risk factor in a case-control study on recurrent venous thrombosis (n= 169). We identified a common haplotype that was significantly associated with tHcy levels. This effect was largely explained by the rs4680 variant, resulting in an increase in tHcy of 10.4% (95% CI 0.01 to 0.21, p=0.03) for 324AA compared with 324GG subjects. Interestingly, we found that the 324AA genotype was more common in venous thrombosis patients (OR 1.61 [95% CI 0.97 to 2.65], p=0.06) compared to control subjects. We show that the COMT rs4680 variant modulates tHcy, and might be associated with venous thrombosis risk as well.

scholarly journals Abnormal Biomarkers of Homocysteine Metabolism in Neonates with Conotruncal Heart Defects

2017 ◽  
Vol 2017 ◽  
pp. 1-5 ◽  
Author(s):  
Piotr Surmiak ◽  
Małgorzata Baumert ◽  
Magdalena Paprotny
Keyword(s):  
Metabolic Pathways ◽  
Congenital Heart ◽  
Heart Defects ◽  
Venous Blood ◽  
Control Group ◽  
Blood Samples ◽  
Metabolism Pathway ◽  
Conotruncal Heart Defects ◽  
Total Homocysteine ◽  
Plasma Total Homocysteine

Objectives. The etiology of conotruncal heart defects (CHD) remains unknown; however relation between homocysteine, folate levels, and congenital heart disease was found. With this perspective in mind, the aim of the study was to investigate biomarkers of homosyteine metabolism pathway in mothers and their neonates with CHD.Material and Methods. Forty-three pairs of mothers and their neonates with CHD and forty pairs of mothers and neonates with nonconotruncal heart defects (non-CHD) were enrolled. The control group (CG) consisted of fifty-nine pairs of mothers and their healthy neonates. For estimating the plasma total homocysteine (tHcy), serum folates, and cobalamin levels, mothers’ venous blood samples and umbilical cord blood were taken in all groups.Results. We observed higher tHcy levels in newborns with CHD in comparison to their mothers and to neonates with non-CHD. Cobalamin levels were significantly lower in neonates with CHD compared to other children. Folates and cobalamin levels were lower in CHD mothers compared to their children.Conclusions. Elevated homocysteine levels in neonates with CHD and folate metabolism disturbances in their mothers were noticed. The observed differences in homocysteine and cobalamin levels between neonates with CHD suggest the influence of various agents disturbing homocysteine metabolic pathways.

scholarly journals Comparison of Blood Collected in Acid-Citrate-Dextrose and EDTA for Use in Human Immunodeficiency Virus Peripheral Blood Mononuclear Cell Cultures

2000 ◽  
Vol 38 (2) ◽  
pp. 858-860 ◽  
Author(s):  
Susan A. Fiscus ◽  
Hrishikesh Chakraborty ◽  
Robin Shepard ◽  
Melissa Goodman
Keyword(s):  
Human Immunodeficiency Virus ◽  
Room Temperature ◽  
Peripheral Blood Mononuclear ◽  
Blood Samples ◽  
Viral Loads ◽  
Hiv Rna ◽  
Culture Positivity ◽  
Immunodeficiency Virus ◽  
Acid Citrate Dextrose ◽  
Citrate Dextrose

Paired blood samples collected in acid-citrate-dextrose and EDTA were compared for human immunodeficiency virus (HIV) infectivity on the day of collection or after 1 day of storage at room temperature. No significant differences between the anticoagulants were observed. Culture positivity was significantly associated with HIV RNA viral loads for both anticoagulants.

scholarly journals The holding temperature of blood during a delay to processing can affect serum and plasma protein measurements

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Milton Ashworth ◽  
Benjamin Small ◽  
Lucy Oldfield ◽  
Anthony Evans ◽  
William Greenhalf ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Room Temperature ◽  
Serum Levels ◽  
Data Interpretation ◽  
Blood Samples ◽  
Specific Manner ◽  
Associated Proteins ◽  
Holding Temperature ◽  
Pai 1 ◽  
Meaningful Data

AbstractAccurate blood-borne biomarkers are sought for diagnosis, prognosis and treatment stratification. Consistent handling of blood is essential for meaningful data interpretation, however, delays during processing are occasionally unavoidable. We investigated the effects of immediately placing blood samples on ice versus room temperature for 1 h (reference protocol), and holding samples on ice versus room temperature during a 3 h delay to processing. Using Luminex multi-plex assays to assess cytokines (n = 29) and diabetes-associated proteins (n = 15) in healthy subjects, we observed that placing blood samples immediately on ice decreased the serum levels of several cytokines, including PAI-1, MIP1-β, IL-9, RANTES and IL-8. During a delay to processing, some analytes, e.g. leptin and insulin, showed little change in serum or plasma values. However, for approximately half of the analytes studied, a delay, regardless of the holding temperature, altered the measured levels compared to the reference protocol. Effects differed between serum and plasma and for some analytes the direction of change in level varied across individuals. The optimal holding temperature for samples during a delay was analyte-specific. In conclusion, deviations from protocol can lead to significant changes in blood analyte levels. Where possible, protocols for blood handling should be pre-determined in an analyte-specific manner.

Betaine: a key modulator of one-carbon metabolism and homocysteine status

2005 ◽  
Vol 43 (10) ◽  
Author(s):  
Per Magne Ueland ◽  
Pål I. Holm ◽  
Steinar Hustad
Keyword(s):  
Carbon Metabolism ◽  
Individual Variability ◽  
Vitamin B ◽  
Total Homocysteine ◽  
Altered Metabolism ◽  
One Carbon Metabolism ◽  
And Gender ◽  
Betaine Homocysteine Methyltransferase ◽  
Plasma Total Homocysteine ◽  
Homocysteine Methyltransferase

AbstractBetaine serves as a methyl donor in a reaction converting homocysteine to methionine, catalysed by the enzyme betaine-homocysteine methyltransferase. It has been used for years to lower the concentration of plasma total homocysteine (tHcy) in patients with homocystinuria, and has recently been shown to reduce fasting and in particular post-methionine load (PML) tHcy in healthy subjects.Betaine exists in plasma at concentrations of about 30μmol/L; it varies 10-fold (from 9 to 90μmol/L) between individuals, but the intra-individual variability is small. Major determinants are choline, dimethylglycine and folate in plasma, folic acid intake and gender.Recent studies have demonstrated that plasma betaine is a stronger determinant of PML tHcy than are vitamin BTo conclude, betaine status is a component of an individual's biochemical make-up with ramifications to one-carbon metabolism. Betaine status should be investigated in pathologies related to altered metabolism of homocysteine and folate, including cardiovascular disease, cancer and neural tube defects.

Oral and transdermal estrogens both lower plasma total homocysteine in male-to-female transsexuals

2003 ◽  
Vol 168 (1) ◽  
pp. 139-146 ◽  
Author(s):  
Erik J. Giltay ◽  
Petra Verhoef ◽  
Louis J.G. Gooren ◽  
Johanna M. Geleijnse ◽  
Evert G. Schouten ◽  
...  
Keyword(s):  
Lower Plasma ◽  
Total Homocysteine ◽  
Male To Female ◽  
Plasma Total Homocysteine
Sign in / Sign up

Export Citation Format

Share Document