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Hcy Levels (hcy + level)

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Medical Sciences	100%

Selected Abstracts

The effect of oral folic acid upon plasma homocysteine, endothelial function and oxidative stress in patients with type 1 diabetes and microalbuminuria

INTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 4 2008
F. Wotherspoon
Summary Aims:, The purpose of this study was to investigate the effect of oral folic acid supplementation upon plasma homocysteine (HCY), endothelial function and oxidative stress on patients with type 1 diabetes and microalbuminuria to test the hypothesis that oral folic acid would lower plasma HCY and thereby improve endothelial function and reduce oxidant stress in this high-risk group of patients. Methods:, We measured plasma HCY, forearm blood flow, total antioxidant status and whole blood glutathione at baseline and after 2 months treatment with oral folic acid or placebo in 16 patients with type 1 diabetes and microalbuminuria. Results:, Plasma HCY fell by 25% in the folic acid group but there was no difference in endothelial function or markers of oxidant stress in the treatment group. Conclusions:, Oral folic acid supplementation successfully lowered plasma HCY levels in patients with type 1 diabetes and microalbuminuria, however this was not associated with improvements in endothelial function or markers of oxidant stress. [source]

Low Dietary Riboflavin but Not Folate Predicts Increased Fracture Risk in Postmenopausal Women Homozygous for the MTHFR 677 T Allele,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 1 2008
Nahid Yazdanpanah
Abstract The MTHFR C677T polymorphism is associated with mildly elevated homocysteine levels when folate and/or riboflavin status is low. Furthermore, a mildly elevated homocysteine level is a risk factor for osteoporotic fractures. We studied whether dietary intake of riboflavin and folate modifies the effects of the MTHFR C677T variant on fracture risk in 5035 men and women from the Rotterdam Study. We found that the MTHFR C677T variant interacts with dietary riboflavin intake to influence fracture risk in women. Introduction: The MTHFR C677T polymorphism is associated with mildly elevated homocysteine (Hcy) levels in the presence of low folate and/or riboflavin status. A mildly elevated Hcy level was recently identified as a modifiable risk factor for osteoporotic fracture. We studied whether dietary intake of riboflavin and folate modifies the effects of the MTHFR C677T polymorphism on BMD and fracture risk. Materials and Methods: We studied 5035 individuals from the Rotterdam Study, ,55 yr of age, who had data available on MTHFR, nutrient intake, and fracture risk. We performed analysis on Hcy levels in a total of 666 individuals, whereas BMD data were present for 4646 individuals (2692women). Results: In the total population, neither the MTHFR C677T polymorphism nor low riboflavin intake was associated with fracture risk and BMD. However, in the lowest quartile of riboflavin intake, female 677- T homozygotes had a 1.8 (95% CI: 1.1-2.9, p = 0.01) times higher risk for incident osteoporotic fractures and a 2.6 (95% CI: 1.3-5.1, p = 0.01) times higher risk for fragility fractures compared with the 677-CC genotype (interaction, p = 0.0002). This effect was not seen for baseline BMD in both men and women. No significant influence was found for dietary folate intake on the association between the MTHFR C677T genotype and fracture risk or BMD. In the lowest quartile of dietary riboflavin intake, T-homozygous individuals (men and women combined) had higher (22.5%) Hcy levels compared with C-homozygotes (mean difference = 3.44 ,M, p = 0. 01; trend, p = 0.02). Conclusions: In this cohort of elderly whites, the MTHFR C677T variant interacts with dietary riboflavin intake to influence fracture risk in women. [source]

Homocysteine-lowering therapy or antioxidant therapy for bone loss in Parkinson's disease,

MOVEMENT DISORDERS, Issue 3 2010
Seung Hun Lee MD
Abstract We investigated whether homocysteine (Hcy)- lowering therapy or an antioxidant prevented bone loss in Parkinson's disease (PD) patients taking levodopa. Forty-two PD patients with low bone mineral density (BMD) taking levodopa were randomly assigned to Hcy-lowering therapy (5 mg folate and 1500 ,g vitamin B12 daily), ,-lipoic acid (,-LA) therapy (1200 mg daily), or control groups. Primary outcomes were BMD changes from baseline to 12 months. Secondary outcomes were changes in Hcy level, and C-telopeptide (CTX) levels at 12 months. Forty-one patients completed the study. Hcy-lowering therapy resulted in significantly greater BMD changes at the lumbar spine (4.4%), total femur (2.8%), and femur shaft (2.8%) than control (P = 0.005,0.023). BMD changes in the ,,LA therapy group were similar to those of the control group, but changes at the trochanter (4.6%) were significantly greater in the ,,LA therapy group than in the control group after adjustment for body mass index changes. Hcy concentrations decreased to 35.2% ± 13.4% in the Hcy-lowering therapy group, but increased in other groups. Serum CTX levels at 12 months tended to be lower in the Hcy-lowering group (0.442 ± 0.024 ng/mL) than control group (0.628 ± 0.039 ng/mL) (P = 0.159). This small trial suggests that Hcy-lowering therapy may prevent bone loss in PD patients taking levodopa. © 2009 Movement Disorder Society [source]

Beta-2-Microglobulin in nocturnal hemodialysis , A comparative study in low and high flux dialysers

HEMODIALYSIS INTERNATIONAL, Issue 1 2005
A.B. Reid
In end-stage renal failure, impaired renal catabolism leads to retention of beta 2 microglobulin (ß2M), identified as the major constituent of hemodialysis (HD) related amyloidosis. It has been previously shown that, while using a high flux (HF) HD membrane, nocturnal hemodialysis (NHD) with its increased time and frequency provides a much higher clearance of ß2M compared to conventional HD. We compared serum ß2M levels between low flux (LF) and HF in a group of 9 NHD patients who dialyse 8 hours 6 nights/week. Fresenius polysulfone LF membrane size F6-F8 HPS dialyser were used for the first 15 months (mth) of NHD (SA 1.3,1.8 m2). Subsequently, polysulfone HF FX80 dialyzer were used (SA 1.8 m2). Blood flow and dialysate flow rates were unchanged throughout the study. ß2M levels were measured at 6, 12, 15 mth on LF and at 6, 12 mth on HF. Albumin, homocysteine (Hcy), and phosphate (Phos) levels were also recorded at these times. ß2M levels trended upwards during the 15 mth on LF (36.6 ± 10.57 at 6 mth vs 47.1 ± 11.7 at 15 mth). On introduction of HF, there was a significant fall in ß2M at 6 mth to 12.4 ± 3.5 (p < 0.003), while ß2M levels were unchanged at 12 mth of HF. A downward trend in Hcy levels with the use of HF was noted (12.9 ± 2.9 at 0 mth Vs 11.1 ± 3.7 at 12 mth). Plasma albumin and Phos levels remained unchanged as did the use of Phos supplementation. Levels of ß2M continued to rise on NHD with LF, indicating inadequate clearance. With the introduction of HF there was a significant fall in ß2M levels consistent with improved clearance. The implications of this are that ß2M clearance may be time and frequency dependent only if dialyser membrane flux is adequate. [source]

Low Dietary Riboflavin but Not Folate Predicts Increased Fracture Risk in Postmenopausal Women Homozygous for the MTHFR 677 T Allele,

Protective Effect of Vitamin E Against Ethanol-Induced Hyperhomocysteinemia, DNA Damage, and Atrophy in the Developing Male Rat Brain

ALCOHOLISM, Issue 7 2009
Alireza Shirpoor
Background:, Chronic alcoholism leads to elevated plasma and brain homocysteine (Hcy) levels, as demonstrated by clinical investigations and animal experiments. It has been posited that elevated levels of Hcy mediate DNA damage, brain atrophy, and excitotoxicity. The current study sought to elucidate the effect of vitamin E on ethanol-induced hyperhomocysteinemia, DNA damage, and atrophy in the developing hippocampus and cerebellum of rats. Methods:, Pregnant Wistar rats received ethanol with or without vitamin E from gestation day 7 throughout lactation. Weight changes in the brain, hippocampus and cerebellum, DNA damage, and Hcy levels in the plasma, hippocampus, and cerebellum of male offspring were measured at the end of lactation. Results:, The results revealed that along with a significant decrease in brain, cerebellum, and hippocampus weights in animals that received alcohol, the levels of DNA damage and Hcy significantly increased. Significant amelioration of brain atrophy and DNA damage as well as restoration of the elevated level of Hcy to that of controls were found in vitamin E-treated rats. Conclusions:, These findings strongly support the idea that ethanol intake by dams during pregnancy and lactation induces Hcy-mediated oxidative stress in the developing hippocampus and cerebellum of offspring rats, and that these effects can be alleviated by vitamin E as an antioxidant. [source]

Hyperhomocysteinemia in pediatric and young adult renal transplant recipients

PEDIATRIC TRANSPLANTATION, Issue 2 2004
Amir Belson
Abstract:, Hyperhomocysteinemia (HHcy) has been recently identified as an important and reversible cardiovascular risk factor in adult and pediatric renal transplant recipients. A retrospective cross-sectional analysis of 70 pediatric and young adult renal transplant recipients was performed to determine the prevalence, and important clinical and laboratory correlates of HHcy. Total homocysteine concentration, free and protein bound, was determined by fluorescence polarization immunoassay using an IMX analyzer. Hyperhomocysteinemia was defined as a serum homocysteine (Hcy) level above the 95th percentile for age. Fifty-four of 70 patients (77%) had HHcy. Comparison of patients with HHcy with patients without HHcy demonstrated no statistical difference in age (p = 0.35), gender (p = 0.76) or donor type (p = 0.20). Patients with HHcy had significantly lower calculated creatinine clearance values (Ccr) (p = 0.02), 67.3 ± 21.2 mL/min/1.73 m2 vs. 90.7 ± 32.3 mL/min/1.73 m2 for patients without HHcy. Immunosuppression did not correlate with the diagnosis of HHcy. Stepwise logistic regression identified patient age (0.18, p = 0.013) and Ccr (,0.04, p = 0.011) as significant variables. In conclusion, HHcy is more common than expected in pediatric renal transplant recipients. Patients with Ccr <80 mL/min/1.73 m2 were statistically more likely to have a diagnosis of HHcy. We recommend that Hcy levels should be evaluated in this high risk population. [source]

Levodopa, methylmalonic acid, and neuropathy in idiopathic Parkinson disease

ANNALS OF NEUROLOGY, Issue 1 2010
Cory Toth MD
Objective Peripheral neuropathy (PN) is thought to be coincidental in patients with idiopathic Parkinson disease (IPD). We sought to examine the prevalence of PN in a population of IPD patients and a potential relationship to levodopa use and fasting methylmalonic acid (MMA) levels. Methods In a prospective cohort study, IPD patients randomly selected from a comprehensive database were compared to control subjects regarding the presence and severity of PN using clinical and electrophysiological measures. IPD severity was determined using the Unified Parkinson's Disease Rating Scale (UPDRS). We determined the relation of levodopa use with serum levels of cobalamin, MMA, and homocysteine (Hcy). We also explored the association between presence and severity of PN and age, duration of IPD, cumulative levodopa dosing, cobalamin, MMA, and Hcy levels. Results Fifty-eight randomly selected IPD patients were compared to 58 age- and sex-matched controls. PN was present in 55% of IPD patients and 9% of controls. Patients with IPD had greater prevalence of PN and fasting MMA/Hcy levels than controls. IPD patients with PN were older and exhibited higher UPDRS scores, fasting MMA/Hcy levels, and cumulative levodopa exposure. PN severity in IPD subjects positively correlated with both levodopa exposure and MMA levels. Interpretation IPD patients have a higher prevalence of PN than controls. Although causality is not established, levodopa exposure is associated with MMA elevation and sensorimotor neuropathy in IPD patients. Cobalamin replacement concurrent with levodopa therapy should be considered to protect against development of PN in IPD patients. ANN NEUROL 2010;67:28,36 [source]

Serum homocysteine concentrations in children with growth hormone (GH) deficiency before and after 12 months GH replacement

CLINICAL ENDOCRINOLOGY, Issue 5 2004
Valentina Esposito
Summary objective, This open, prospective study was designed to evaluate the effect of growth hormone deficiency (GHD) and GH replacement therapy on serum homocysteine (Hcy) concentration in children with GHD. subjects, Seventeen prepubertal children with GHD (11 boys and six girls) aged 8·6 ± 1·9 years were studied before and after 12 months of GH replacement therapy at a dose of GH of 30 µg/kg/day. Seventeen healthy children acted as controls and were matched for age, sex and body mass index (BMI). methods, At study entry, height, weight, blood pressure, serum Hcy, serum IGF-I, total-low density lipoprotein (LDL)- and high density lipoprotein (HDL) cholesterol, triglycerides, free T4, free T3, vitamin B12, folate, glucose and creatinine were measured in all subjects. The atherogenic index (AI) was also calculated as the ratio of total cholesterol/HDL cholesterol (T/HDL). In GHD children these parameters were also revaluated after 12 months of GH therapy. results, At study entry height and serum IGF-I were significantly lower, as expected, in GHD patients than in controls (P < 0·0001 and P < 0·007, respectively). Serum Hcy levels were significantly higher in GHD patients than in healthy children (8·4 ± 2·9 vs. 6·0 ± 2·9 µmol/l; P < 0·03), although the absolute values were within the normal values for age and sex. There were no significant differences at baseline with respect to blood pressure, serum vitamin B12, folate, fT3, fT4, lipid profile, creatinine and glucose levels. After 12 months of GH replacement therapy height and serum IGF-I increased significantly compared to pretreatment values (P < 0·0001); serum Hcy levels decreased significantly (6·0 ± 3·3 µmol/l; P < 0·002) compared to baseline values, becoming similar to control values. Total cholesterol (3·5 ± 0·6 mmol/l) and the AI (2·5 ± 0·8) decreased significantly with respect to both pretreatment (4·2 ± 1·0 mmol/l; P < 0·0002 and 3·4 ± 0·8; < 0·002, respectively) and control values (4·2 ± 0·4 mmol/l; P < 0·0005 and 3·3 ± 1·1; P = 0·02, respectively). conclusions GHD in children is associated with higher serum levels of Hcy compared to controls, without significantly affecting the lipid profile. GH replacement for 12 months significantly decreased the Hcy levels and improved the lipid profile with a decrease of total cholesterol and the total/HDL cholesterol ratio, compared to pretreatment values. Given the small number of patients, further larger studies are needed to clarify whether these results may have significant effects in the prevention of cardiovascular disease in adulthood. [source]