Homocysteine but not neopterin declines in demented patients on B vitamins

Summary. Inflammation and immune system activation seem to play an important role in the development and progression of dementia. Hyperhomocysteinemia is common in various forms of dementia, and a significant relationship was found between concentrations of homocysteine and immune activation marker neopterin. B vitamin supplementation is able to slow-down homocysteine formation in patients. In an open-label study, effects of B vitamin supplementation (Beneuran compositum ^?) on concentrations of homocysteine and neopterin were investigated in 58 patients with Alzheimer’s disease (n = 30), vascular dementia (n = 12) and mild cognitive impairment (n = 16). In all groups of patients, a significant percentage of patients presented with homocysteine concentrations >15 μmol/L and with elevated concentrations of immune activation marker neopterin. Decline of homocysteine concentrations was observed after one month of B vitamin supplementation (all p < 0.01; paired Kruskal-Wallisn-test). By contrast, neopterin concentrations remained unchanged (all p > 0.05). B vitamin supplementation in patients with various forms of dementia did not influence neopterin concentrations, which indicates that the degree of immune activation and inflammation remained unchanged. The question remains, if lowering of homocysteine by folate supplementation alone could have any beneficial effect to modulate the course of dementia development and if longer period of supplementation would also ameliorate immune system activation status.     

Moderate hyperhomocysteinaemia and immune activation in Parkinson's disease

Moderate hyperhomocysteinaemia has been linked to an increased risk for cardiovascular diseases. Increased homocysteine concentrations may follow folate depletion due to insufficient dietary intake of the vitamin, but there is also some indication that immune activation could play a role. In this preliminary study, homocysteine, folate, and vitamin B(12) concentrations were measured in 19 patients with Parkinson's disease, 61-90 years of age, and compared to a healthy control group of similar age and to neopterin concentrations as an indicator of immune activation. A subgroup of patients presented with increased homocysteine and low folate concentrations. Homocysteine levels correlated inversely with vitamins folate and B(12) and positively with neopterin concentrations. Disturbed homocysteine metabolism in Parkinson's disease may be associated with vitamin deficiency and with immune system activation which may underlie folate depletion.     

Homocysteine and serum markers of immune activation in primary dystonia.

The cause of primary dystonia remains unknown. Several reports point to immune system disturbances in primary dystonia and a recent study demonstrated hyperhomocysteinemia in cervical dystonia. Homocysteine (HCY) is an amino acid and elevated HCY concentrations were shown to be associated with immune system activation and increased neopterin serum concentrations. We examined HCY serum concentrations together with serum markers of immune activation in patients with different types of primary dystonia. Eighty-three patients with different types of primary dystonia were included and investigated at least 3 months following botulinum toxin treatment. Thirty-six healthy volunteers with similar age and sex distribution served as controls. Total serum HCY, kynurenine, and tryptophan concentrations were determined by high-performance liquid chromatography; neopterin, folate, and vitamin B12 concentrations were measured by immunoassays. Routine blood analysis, including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and white blood count (WBC), was performed. Patients with primary dystonia had significantly higher HCY concentrations compared to controls. Among the dystonia subtypes, no significant difference of HCY serum concentrations was observed. CRP and ESR were within the normal range in >90% of the patients and all had normal WBC. Neopterin, kynurenine, and tryptophan serum concentrations were similar in patients and controls and not correlated with HCY serum concentrations. The results provide evidence against enhanced cellular immune activation in patients with primary dystonia. However, hyperhomocysteinemia was present in all dystonia subtypes and unrelated to immune activation in this study. HCY is a neuronal excitotoxic amino acid and hyperhomocysteinemia is considered an independent vascular risk factor. Further studies are required to define the background of hyperhomocysteinemia in primary dystonia.     

Homocysteine, folate, vitamin B-12 and vitamin B-6 in patients receiving antiepileptic drug monotherapy

We hypothesized that elevated plasma homocysteine concentrations (hyperhomocysteinemia) exist in patients receiving antiepileptic drugs (AED), and a long-term administration of AED may result in an increased risk of occlusive vascular disease in these patients. A total of 62 patients who received AED monotherapy (phenytoin, lamotrigine, carbamazepine or valproate) participated in this study. Blood concentrations of homocysteine, folate, vitamin B-12 and pyridoxal-5'-phosphate (PLP, a coenzyme form of vitamin B-6) were measured, and thermolabile genotypes of 5, 10-methylenetetrahydrofolate reductase (MTHFR) were also determined. Of 62 patients, only seven (11.4%) had hyperhomocysteinemia. Of 20 patients who received phenytoin, three (15.0%) had hyperhomocysteinemia, whereas 85% of these had plasma folate concentrations below the normal range. However, erythrocyte folate concentrations were abnormally low in only 25% of the patients who received phenytoin. Valproate administration increased serum vitamin B-12 concentrations. Over 55% of the entire patients had PLP concentrations below the normal range, although the reason is unknown. Only three patients had the homozygous thermolabile genotype of MTHFR; therefore, meaningful statistical analysis was not possible in this study. However, one patient with homozygous genotype who received phenytoin therapy had hyperhomocysteinemia with poor folate nutritional status, and the other two had normal homocysteine concentrations with normal folate status. Our data suggest that hyperhomocysteinemia is not a serious clinical concern in epileptic patients when folate nutriture is adequate.     

轻度认知障碍患者血浆同型半胱氨酸和血清维生素B12及叶酸水平变化研究

目的 探讨轻度认知障碍(MCI)患者血浆同型半胱氨酸(Hcy)、血清维生素B12及叶酸水平的变化及相互关系.方法 MCI组80例,正常对照组80例,检测所有观察对象的血浆同型半胱氨酸、血清VitB12及叶酸水平并分析相互关系.结果 MCI组血浆Hey水平较正常组显著增高为(18.9±8.8)μmol/L vs(14.35±5.7)μmol/L,而血清叶酸和VitB12水平在正常组和MCI组之间并没有显著差异;相对于血浆Hey正常组,MCI比值比(0R)在轻、中度高同型半胱氨酸血症组中增高(OR=1.85,95%CI=1.56～2.95;OR=3.32,95%CI=1.61～6.48;P=0.001);无论在MCI组还是在正常组中,血浆Hey与血清叶酸及Vit B12的水平均呈负相关.结论 血浆Hey水平升高与MCI相关,叶酸和VitB122缺乏可能导致血浆Hcy水平升高.     

Lack of association between plasma homocysteine and inflammation in psychogeriatric patients

Background/Objectives: In previous studies we observed a high incidence of elevated plasma homocysteine (tHcy) concentrations in psychogeriatric patients. Plasma tHcy is increased in folate deficiency. Folates are sensitive to oxidative stress. Oxidative stress, caused by inflammatory processes, could represent an endogenous reason for folate deficiency, even when the dietary intake of the vitamin is within the recommended range. It has been suggested that oxidative stress rather than insufficient folate intake causes hyperhomocysteinemia in different forms of psychogeriatric diseases. In the present study we investigated the association between plasma tHcy and C-reactive protein (CRP), a sensitive marker for inflammation, in psychogeriatric patients. Methods: Plasma tHcy, its main determinants, and CRP were measured in plasma and serum of 132 psychogeriatric patients (53 males and 79 females, mean age 75 +/- 12 years). Results: In the psychogeriatric patients, plasma tHcy was elevated and blood folate and serum creatinine were lower than in control subjects, whereas serum CRP concentrations did not differ significantly. We also subdivided the psychogeriatric patients into different diagnosis groups, yet there were no differences in serum CRP concentrations in these groups compared with age-matched control groups. There was a significant correlation between plasma tHcy and serum CRP (rho = 0.19, p < 0.05). A stepwise multiple regression analysis including serum CRP, age, blood folate, serum cobalamin, serum methylmalonic acid and serum creatinine showed that only blood folate (p < 0.001), age (p < 0.001), serum creatinine (p < 0.001), serum cobalamin (p < 0.001), and serum methylmalonic acid (p < 0.001) independently predicted plasma tHcy concentration. Thus CRP concentration was not an independent predictor of plasma tHcy. Conclusion: The present study did not show any association between inflammatory status and plasma tHcy concentration in psychogeriatric patients.     

Homocysteine,vitamin B6, and vascular disease in AD patients

BACKGROUND: Cerebrovascular disease is a cause of dementia and is associated with elevated plasma levels of homocysteine. Patients with AD tend to have unexplained elevations of homocysteine concentrations vs healthy control subjects. Vitamin B(6) status, a potential determinant of plasma homocysteine, has not been characterized in patients with AD. OBJECTIVE: To investigate plasma homocysteine, vitamin B(6) status, and the occurrence of vascular disease in patients with AD. METHODS: Forty-three patients with AD and 37 control subjects without AD were studied for homocysteine, B vitamin status (folate, vitamin B(12), pyridoxal-5'-phosphate [PLP]), kidney function (creatinine), and thyroid function (thyroid-stimulating hormone, thyroxin). In addition, the presence of vascular disease was assessed by reviewing both medical histories and brain imaging data provided by CT and MRI. RESULTS: The OR for elevated plasma homocysteine (>12 micromol/L) was only 2.2 (not significant) for subjects with AD. In contrast, the OR was 10.0 (p = 0.03) for subjects with vascular disease (n = 26). The OR for low plasma PLP (<25 nmol/L) was 12.3 (p = 0.01) for patients with AD. No significant relationship was observed between vascular disease and PLP level or between plasma homocysteine and PLP concentrations. CONCLUSIONS: Elevated plasma homocysteine in patients with AD appears related to vascular disease and not AD pathology. In addition, low vitamin B(6) status is prevalent in patients with AD. It remains to be determined if elevated plasma homocysteine or low vitamin B(6) status directly influences AD pathogenesis or progression.     

Cobalamin, folate, methylmalonic acid, homocysteine, and gastritis markers in dementia

The prevalence of dementia disorders, cobalamin and/or folate deficiency as well as gastritis increases with age. To investigate whether there is an association between these conditions, plasma homocysteine (Hcy), serum methylmalonic acid, serum cobalamin and blood folate concentrations were measured. Gastritis was indirectly diagnosed by measuring serum antibodies against H,K-ATPase, HELICOBACTER PYLORI and intrinsic factor, using enzyme-linked immunosorbent assays. The studied groups consisted of 47 patients with Alzheimer's disease (AD), 9 with AD pathology in combination with additive vascular lesions, 59 with vascular dementia, 8 who were cognitively impaired, and 101 control cases. Plasma Hcy concentrations were significantly elevated in the dementia groups, with the highest levels in patients with vascular pathology. We conclude that hyperhomocysteinemia is a common finding in patients with dementia disorders of different etiologies. The markers for gastritis did not contribute to an elucidation of a possible connection between this condition, dementia disorders, or cobalamin/folate deficiency.     

Folate/vitamin-B12 prevents chronic hyperhomocysteinemia-induced tau hyperphosphorylation and memory deficits in aged rats

Hyperhomocysteinemia is associated with an increased risk of Alzheimer's disease (AD). Our previous work has demonstrated that combined folate and vitamin B12 (vit-B12) supplementation prevents tau hyperphosphorylation and memory deficits induced by acute administration of homocysteine in young rats. Here, we further investigated whether folate/vit-B12 supplementation is also effective in aged rats with a chronically high level of homocysteine. 18-month-old rats were injected with homocysteine via the vena caudalis with or without a concurrent folate/vit-B12 supplementation for 28 weeks. We found that hyperhomocysteinemia induced tau hyperphosphorylation and accumulation in hippocampus and cortex. Concurrent signaling changes included the activation of glycogen synthase kinases-3β, cyclin-dependent kinase-5, c-Jun N-terminal kinase, extracellular signal-regulated kinase, and p38MAPK, and inhibition of protein phosphatase 2A. Although the ability to learn was not affected, the aged rats exhibited significant memory deficits. Folate/vit-B12 supplementation attenuated these biochemical and behavioral correlates. These data demonstrate that folate/vit-B12 supplementation is also effective in a chronic hyperhomocysteinemia model in reversing the AD-like tau pathologies and memory deficits.     

Tryptophan degradation and immune activation in Alzheimer's disease

Summary. Alzheimer's disease (AD) is likely associated with systemic immune activation. During immune response, interferon-gamma stimu-lates indoleamine 2,3-dioxygenase (IDO) converting tryptophan to N-formylkynurenine followed by kynurenine in an ensuing step. Thus, IDO activity is estimated by the kynurenine per tryptophan quotient (Kyn/Trp). In 21 patients suffering from AD, in 20 controls of similar age, and in 49 blood donors we measured serum tryptophan and kynurenine concentrations by HPLC. Lower tryptophan concentrations were found in elderly control subjects compared to blood donors (62.1 vs. 73.0 μM, p < 0.005). Tryptophan concentrations tended to be still lower in AD patients (54.4 μM, p = 0.07) compared to elderly controls. Enhanced tryptophan degradation in patients was reflected by significantly increased Kyn/Trp (46.1 vs. 34.1 in elderly controls, p < 0.05). Correlations were found in patients between Kyn/Trp and concentrations of soluble immune markers in serum, i.e., neopterin, interleukin-2 receptor and tumor necrosis factor receptor (all p < 0.001). Increased Kyn/Trp was associated with reduced cognitive performance. Tryptophan degradation due to immune activation may exert impact on the pathogenesis of AD. Received May 15, 1999; accepted August 24, 1999     

Increased plasma levels of interleukin-1, interleukin-6 and alpha-1-antichymotrypsin in patients with Alzheimer's disease: peripheral inflammation or signals from the brain?

Plasma concentrations of interleukin-1beta (IL-1beta), interleukin-6 (IL-6), C reactive protein (CRP) and alpha-1-antichymotrypsin (ACT) in 145 patients with probable Alzheimer's disease (AD) and 51 non-demented controls were measured. To investigate the cellular activation of peripheral immune system, plasma levels of neopterin were also investigated. Plasma levels of IL-1 were detectable in 17 patients with AD (13%) and only in one control (2%) and average levels of IL-1 were higher in AD patients than in controls (p < 0.001). IL-6 plasma levels were detectable in a higher proportion of AD and controls (53% and 27%, respectively), and were increased in patients with AD (p < 0.001). Plasma levels of ACT were increased in patients with AD (p < 0.001) and CRP levels were in the normal range. Plasma levels of neopterin were slightly lower in AD patients than in controls, but differences were not statistically significant. No significant correlation was observed between IL-1 and IL-6 levels or neopterin and cytokine levels in plasma from AD patients. Plasma levels of ACT negatively correlated with cognitive performances, as assessed by the mini mental state examination (MMSE; R = -0.26, p < 0.02) and positively correlated with the global deterioration state (GDS) of AD patients (R = 0.30, p < 0.007). Present findings suggested that detectable levels of circulating cytokines and increased ACT might not be derived by activation of peripheral immune system of AD patients. Detection of these molecules might be used for monitoring the progression of brain inflammation associated with AD.     

Elevated plasma homocysteine levels in patients treated with levodopa: association with vascular disease

BACKGROUND: Hyperhomocysteinemia is a risk factor for vascular disease and potentially for dementia and depression. The most common cause of elevated homocysteine levels is deficiency of folate or vitamin B(12). However, patients with Parkinson disease (PD) may have elevated homocysteine levels resulting from methylation of levodopa and dopamine by catechol O-methyltransferase, an enzyme that uses S-adenosylmethionine as a methyl donor and yields S-adenosylhomocysteine. Since S-adenosylhomocysteine is rapidly converted to homocysteine, levodopa therapy may put patients at increased risk for vascular disease by raising homocysteine levels. OBJECTIVES: To determine whether elevations in plasma homocysteine levels caused by levodopa use are associated with increased prevalence of coronary artery disease (CAD), and to determine what role folate and vitamin B(12) have in levodopa-induced hyperhomocysteinemia. DESIGN/METHODS: Subjects included 235 patients with PD followed up in a movement disorders clinic. Of these, 201 had been treated with levodopa, and 34 had not. Blood samples were collected for the measurement of homocysteine, folate, cobalamin, and methylmalonic acid levels. A history of CAD (prior myocardial infarctions, coronary artery bypass grafting, or coronary angioplasty procedures) was prospectively elicited. We analyzed parametric data by means of 1-way analysis of variance or the t test, and categorical data by means of the Fisher exact test or chi(2) test. RESULTS: Mean +/- SD plasma homocysteine levels were significantly higher in patients treated with levodopa (16.1 +/- 6.2 micro mol/L), compared with levodopa-na?ve patients (12.2 +/- 4.2 micro mol/L; P<.001). We found no difference in the plasma concentration of folate, cobalamin, or methylmalonic acid between the 2 groups. Patients whose homocysteine levels were in the higher quartile (>or=17.7 micro mol/L) had increased prevalence of CAD (relative risk, 1.75; 95% confidence interval, 1.08-2.70;P=.04). CONCLUSIONS: Levodopa therapy, rather than PD, is a cause of hyperhomocysteinemia in patients with PD. Deficiency of folate or vitamin B(12) levels does not explain the elevated homocysteine levels in these patients. To our knowledge, this is the first report that levodopa-related hyperhomocysteinemia is associated with increased risk for CAD. These findings have implications for the treatment of PD in patients at risk for vascular disease, and potentially for those at risk for dementia and depression.     

Plasma homocysteine levels in multiple sclerosis

BACKGROUND: There is evidence that homocysteine contributes to various neurodegenerative disorders, and elevated plasma homocysteine levels have been observed in patients with multiple sclerosis (MS). OBJECTIVE: To investigate if and why plasma homocysteine levels are increased in MS, and whether they play a role in the disease course. METHODS: We compared plasma levels of homocysteine in 88 patients with MS and 57 healthy controls. In the MS group, 28 had a benign course, 37 were secondary progressive, and 23 primary progressive. To explore the underlying mechanisms, we measured serum levels of vitamins B6 and B12, folate, interleukin (IL)-12, tumour necrosis factor (TNF)-alpha, leukocyte nitric oxide production, and plasma diene conjugate levels (measure of oxidative stress). RESULTS: Mean (SD) plasma homocysteine concentration was higher in patients (13.8 (4.9) micromol/l) than in controls (10.1 (2.5) micromol/l; p<0.0001). However, there were no significant differences in homocysteine levels between the three clinical subgroups of MS. Serum concentrations of vitamin B6, vitamin B12, and folate were not different between patients with MS and controls. In the MS group, there were no correlations between plasma homocysteine levels and the serum concentrations of IL-12 or TNF-alpha, leukocyte nitric oxide production, or plasma diene conjugate levels. CONCLUSIONS: Elevated plasma homocysteine occurs in both benign and progressive disease courses of MS, and seems unrelated to immune activation, oxidative stress, or a deficiency in vitamin B6, vitamin B12, or folate.     

Homocysteine, vitamin B12, and folic acid levels in Alzheimer's disease, mild cognitive impairment, and healthy elderly: baseline characteristics in subjects of the Australian Imaging Biomarker Lifestyle study

There is some debate regarding the differing levels of plasma homocysteine, vitamin B12 and serum folate between healthy controls (HC), mild cognitive impairment (MCI), and Alzheimer's disease (AD). As part of the Australian Imaging Biomarker Lifestyle (AIBL) study of aging cohort, consisting of 1,112 participants (768 HC, 133 MCI patients, and 211 AD patients), plasma homocysteine, vitamin B12, and serum and red cell folate were measured at baseline to investigate their levels, their inter-associations, and their relationships with cognition. The results of this cross-sectional study showed that homocysteine levels were increased in female AD patients compared to female HC subjects (+16%, p-value < 0.001), but not in males. Red cell folate, but not serum folate, was decreased in AD patients compared to HC (-10%, p-value = 0.004). Composite z-scores of short- and long-term episodic memory, total episodic memory, and global cognition all showed significant negative correlations with homocysteine, in all clinical categories. Increasing red cell folate had a U-shaped association with homocysteine, so that high red cell folate levels were associated with worse long-term episodic memory, total episodic memory, and global cognition. These findings underscore the association of plasma homocysteine with cognitive deterioration, although not unique to AD, and identified an unexpected abnormality of red cell folate.     

Homocysteine in restless legs syndrome

BACKGROUND AND PURPOSE: Total plasma homocysteine (tHcy) may be a risk factor for vascular diseases and is associated with renal failure or deficiency of vitamin B12 or folate. Recently, elevated tHcy concentrations were observed in patients with Parkinson's disease (PD), particularly those under levodopa treatment. Our objective was to determine whether changes in tHcy are also found in patients with restless legs syndrome (RLS) in relation to levodopa treatment and whether folate and vitamins B6 and B12 play a role in RLS. METHODS: In a total of 228 subjects, tHcy and B vitamin status (vitamins B6 and B12, folate) were studied: 97 patients with idiopathic RLS (40 under levodopa therapy), 39 with PD (25 under levodopa therapy), and 92 healthy controls adjusted for age and gender. RESULTS: No significant differences were observed in tHcy levels between RLS patients and controls or between the RLS groups without treatment or with levodopa or dopamine agonist treatment. Mean tHcy was significantly higher in PD patients (13.8 micromol/l) than in either RLS patients (11.7 micromol/l) or controls (11.0 micromol/l; p<0.001). There was an inverse association between tHcy and vitamin B12 in each group. CONCLUSIONS: RLS and, in particular, levodopa treatment in RLS are not associated with hyperhomocysteinemia. Elevated tHcy could, however, be confirmed in PD patients.     

Hyperhomocysteinemia in Tunisian bipolar I patients

Aims: The aim of the present study was to investigate hyperhomocysteinemia in Tunisian bipolar I patients according to 5,10‐methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism. Methods: The subjects consisted of 92 patients with bipolar I disorder diagnosed according to DSM‐IV, and 170 controls. Plasma total homocysteine, folate and vitamin B12 were measured. MTHFR C677T polymorphism was determined by polymerase chain reaction–restriction fragment length polymorphism. Results: Compared with controls, patients had a significantly higher homocysteine level (16.4 ± 9.8 vs 9.6 ± 4.5 µmol/L; P < 0.001) and a significantly lower folate level (3.2 ± 0.9 vs 6.5 ± 3.2 µg/L; P < 0.001). C677T MTHFR polymorphism genotype frequencies were in Hardy–Weinberg equilibrium. After adjustment for MTHFR C677T genotypes, hypofolatemia, hypovitamin B12 and for potential confounding factors, the odds ratio (OR) of hyperhomocysteinemia associated with bipolar disorder remained significant (OR, 5.53; 95% confidence interval: 1.92–15.86; P = 0.001). In patients, there was no significant change in hyperhomocysteinemia, hypofolatemia and hypovitamin B12 with regard to the clinical and therapeutic characteristics, whereas the highest prevalence of hyperhomocysteinemia was found in depressive patients and when illness duration was >12 years. Hypofolatemia was seen in all patients on lithium and in the majority of patients on carbamazepine, and the highest prevalence of hypovitamin B12 was noted in patients taking carbamazepine. Conclusion: Hyperhomocysteinemia was more frequent in bipolar I patients independent of C677T polymorphism. Patients had reduced levels of folate, which modulates homocysteine metabolism. Indeed, this finding indicates that folate supplementation may be appropriate for bipolar patients with hyperhomocysteinemia.     

Plasma homocysteine, MTHFR C677T, CBS 844ins68bp, and MTHFD1 G1958A polymorphisms in spontaneous cervical artery dissections

Abstract. Mild hyperhomocysteinemia is a probable risk factor for atherosclerotic diseases and stroke. Recently, associations of elevated plasma homocysteine concentrations in the acute phase and of MTHFR 677 TT genotype with spontaneous cervical artery dissections (sCAD) have been reported. The purpose of this study was to test this hypothesis in the currently largest sample of patients with sCAD, taking into account known factors influencing plasma homocysteine levels. Ninety-five patients with past sCAD were compared with 95 age- and sex-matched healthy individuals. Homocysteine, vitamin B6, B12, folate, and polymorphisms of methylenetetrahydrofolate reductase (MTHFR C677T), cystathionine -synthase (CBS 844ins68bp) and methylenetetrahydrofolate dehydrogenase/methenyltetrahydrofolate cyclohydrolase/formyltetrahydrofolate synthetase (MTHFD1 G1958A) were assessed and any associations were analysed using multivariate statistics. The occurrence of sCAD was associated with elevated homocysteine levels with an odds ratio of 1.327 per 20 % percentile. Homocysteine levels were influenced by gender, smoking status, occurrence of hypertension, vitamin B12 and folate levels, and by the MTHFR TT genotype. MTHFR, CBS 844ins68bp, and MTHFD1 G1958A genotype were not independently associated with the occurrence of sCAD. These data suggest that elevated homocysteine is associated with the occurrence of sCAD. The MTHFR C677T polymorphism is associated with the homocysteine level.     

The effect of B-vitamins on hyperhomocysteinemia in patients on antiepileptic drugs

Patients on antiepileptic drugs (AEDs) may have elevated levels of plasma total homocysteine (p-tHcy). The aim of this study was to assess the effect of B-vitamin supplementation on the levels of p-tHcy and markers of endothelial activation and lipid peroxidation. A total of 33 adult patients on AEDs were identified with either fasting (Group 1, n=23) or post methionine load (PML) (Group 2, n=10) hyperhomocysteinemia. Subjects were supplemented with B-vitamins for 30 days: folic acid 0.4 mg, pyridoxine 120 mg and riboflavin 75 mg per day. After supplementation, serum folate and pyridoxal phosphate had increased, while fasting and PML p-tHcy had decreased (P<0.0001) by 36 and 26%, respectively. Prior to supplementation, the Group 1 patients had elevated levels of P-selectin and von Willebrand factor (vWF) (P=0.05 and 0.03, respectively). After supplementation, the levels of intercellular cell adhesion molecules had decreased (P=0.01) and E-selectin decreased nonsignificantly (P=0.07). However, the levels of vascular cell adhesion molecules had increased (P<0.0001), while lipid peroxidation were unchanged. In conclusion, the combined supplementation with folic acid, pyridoxine and riboflavin reduced fasting and PML hyperhomocysteinemia in patients on AEDs. Patients with fasting hyperhomocysteinemia had elevated levels of P-selectin and vWF, which may indicate an increased risk of cardiovascular disease. Furthermore, B-vitamin supplementation influenced endothelial activation, although the clinical implication is uncertain.     

Hyperhomocysteinemia in children treated with antiepileptic drugs is normalized by folic acid supplementation

PURPOSE: To assess the prevalence of hyperhomocysteinemia in pediatric patients treated with antiepileptic drugs (AEDs) and to evaluate the effect of folic acid supplementation on plasma total homocysteine (tHcy) concentrations in hyperhomocysteinemic patients. METHODS: 123 patients from three regional hospitals participated in the study. Patients with hyperhomocysteinemia were included in a 3-month double-blind randomized trial testing oral folic acid supplementation (1 mg/day) versus placebo. RESULTS: Hyperhomocysteinemia (tHcy >10.4 micromol/L) was present in 19 of 123 patients. Patients with hyperhomocysteinemia were older (13.7 +/- 4 vs. 11.0 +/- 3.9 years) and had significantly lower folate and cobalamin concentrations. Multidrug (two or more) AED treatment and duration of therapy correlated significantly with elevated total homocysteine (tHcy) and low folate. In contrast, polymorphisms in the methylene tetrahydrofolate reductase gene (MTHFR 677 C-->T, 1298 A-->C, 1793 G-->A) had no significant impact on tHcy. Nine of 19 patients with hyperhomocysteinemia were randomized to placebo, whereas the remaining 10 patients received folic acid supplementation. Folic acid supplementation resulted in a significant increase of folate and decrease of tHcy, whereas both parameters remained unchanged in the placebo group. CONCLUSIONS: Hyperhomocysteinemia is present in 15.5% of children receiving long-term AED treatment. Multidrug treatment and long duration of therapy enhance the risk for hyperhomocysteinemia. Folic acid supplementation significantly reduces tHcy. We recommend assessment of serum folate and plasma tHcy in children receiving AEDs.     

Homocysteine and B vitamins relate to brain volume and white-matter changes in geriatric patients with psychiatric disorders.

OBJECTIVE: There is a growing literature on the relationship between low serum B-vitamins, elevated homocysteine, and cognitive impairment; however, few studies have examined radiological markers of associated neuropathology in geropsychiatry inpatients. The authors examined the relationship of homocysteine, folate, and vitamin B12 with magnetic resonance imaging (MRI) markers of neuropathology. METHODS: In this archival study, authors reviewed the MRIs and medical records of 34 inpatients in a geriatric psychiatry unit. Patients were selected if folate, B12, and/or homocysteine levels had been assessed and if the appropriate clinical MRIs were performed (19 men; mean age, 75 years). Patients with schizophrenia or current substance dependence were excluded. The relationships between MRI volume measures, white-matter hyperintensity (WMH) grade, and serum concentrations of folate, B12, and homocysteine were analyzed, using age-adjusted Pearson correlations. RESULTS: Homocysteine was related to WMH grade, but not brain-volume measures. Folate was associated with hippocampus and amygdala, and negatively associated with WMH. B12 level was not statistically associated with any brain measure. CONCLUSIONS: Elevated homocysteine and low folate were associated with radiological markers of neuropathology. Since no patient had clinically deficient folate, it may be important to rethink what defines functionally significant micronutrient deficiency and explore what this means in different age- and health-status groups. Larger samples will be needed to assess interactions between homocysteine, micronutrients, and other neuropathology risk factors.