Serum tHcy Levels Research Articles

S-adenosylhomocysteine hydrolase over-expression does not alter S-adenosylmethionine or S-adenosylhomocysteine levels in CBS deficient mice

Elevated plasma total homocysteine (tHcy) is associated with a number of human diseases including coronary artery disease, stroke, osteoporosis and dementia. It is highly correlated with intracellular S-adenosylhomocysteine (SAH). Since SAH is a strong inhibitor of methyl-transfer reactions involving the methyl-donor S-adenosylmethionine (SAM), elevation in SAH could be an explanation for the wide association of tHcy and human disease. Here, we have created a transgenic mouse (Tg-hAHCY) that expresses human S-adenosylhomocysteine hydrolase (AHCY) from a zinc-inducible promoter in the liver and kidney. Protein analysis shows that human AHCY is expressed well in both liver and kidney, but elevated AHCY enzyme activity (131% increase) is only detected in the kidney due to the high levels of endogenous mouse AHCY expression in liver. Tg-hAHCY mice were crossed with mice lacking cystathionine β-synthase activity (Tg-I278T Cbs−/−) to explore the effect to AHCY overexpression in the context of elevated serum tHcy and elevated tissue SAM and SAH. Overexpression of AHCY had no significant effect on the phenotypes of Tg-I278T Cbs−/− mice or any effect on the steady state concentrations of methionine, total homocysteine, SAM, SAH, and SAM/SAH ratio in the liver and kidney. Furthermore, enhanced AHCY activity did not lower serum and tissue tHcy or methionine levels. Our data suggests that enhancing AHCY activity does not alter the distribution of methionine recycling metabolites, even when they are greatly elevated by Cbs mutations.

Correlation between homocysteine levels and stroke in patients with acute ischemic stroke

Ischemic strokes are mostly caused by atherosclerosis, and increased homocysteine levels are considered to play a role in atherosclerosis. The aim of this study was to investigate serum total homocysteine (tHcy) levels in the first 24 h of ischemic stroke patients and to analyze the correlation between tHcy levels and the clinical severity of ischemic stroke. The study included a total of 151 participants including a patient group of 83 patients diagnosed with acute ischemic stroke and a control group of 68 age- and gender-matched subjects with no history of ischemic vascular diseases between June 2006 and December 2007. Demographic characteristics of were recorded for each participant and stroke severity was assessed using the modified Rankin Scale (mRS) in each patient. Serum tHcy, vitamin B12, folic acid, and fibrinogen levels as well as platelet count and lipid profiles were measured for each participant. Serum tHcy levels were significantly higher and the folic acid levels were significantly lower in the patient group compared to the control group (p

Genetic polymorphisms and folate status.

Moderate hyperhomocysteinemia‐induced low folate status is an independent risk factor for cardiovascular disease, dementia, and depression. Folate is an essential cofactor in the one‐carbon metabolism pathway and is necessary in amino acid metabolism, purine and thymidylate synthesis, and DNA methylation. In the folate cycle and homocysteine metabolism, folate, vitamin B12, vitamin B6, and vitamin B2 are important cofactors. Many enzymes are involved in folate transport and uptake, the folate pathway, and homocysteine (Hcy) metabolism, and various polymorphisms have been documented in these enzymes. Serum folate and total Hcy (tHcy) levels are influenced by folate intake and genetic polymorphisms in 5,10‐methylenetertahydrofolate reductase (MTHFR) such as C677T. The prevalence of the MTHFR 677TT genotype varies across ethnic groups and regions, with a frequency of approximately 15% in Japanese populations. Individuals with the TT genotype have significantly higher tHcy levels and lower folate levels in serum than those with the CT and TT genotypes. However, administration of folic acid has been shown to eliminate these differences. Moreover, data have suggested that interventions based on genotype may be effective for motivating individuals to change their lifestyle and improve their nutrition status. Accordingly, in this review, we discuss the effects of MTHFR C677T polymorphisms on serum tHcy and folate levels with folic acid intervention and evaluate approaches for overcoming folic acid deficiency and related symptoms.

Association between the MTHFR C677T polymorphism, blood folate and vitamin B12 deficiency, and elevated serum total homocysteine in healthy individuals in Yunnan Province, China

BackgroundAn increased serum total homocysteine (tHcy) concentration is typically associated with genetic defects involved in Hcy metabolism or related nutritional deficiencies. In this study, the combined effects of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and folate and vitamin B12 deficiency on serum total Hcy (tHcy) levels were evaluated in a healthy Chinese population in Yunnan Province, China. MethodsThe MTHFR C677T polymorphism was genotyped in 330 volunteers (164 men and 166 women) using polymerase chain reaction-restriction fragment length polymorphism analysis. Folate, vitamin B12, and tHcy concentrations were determined by corpuscle immune chemiluminescence assays. The tHcy concentration was determined using an enzymatic assay. ResultsSignificant negative correlations (p<0.001) were observed between the serum levels of tHcy and folate (r=−0.252) and vitamin B12 (r=−0.243). Men had significantly higher serum tHcy concentrations than women (p<0.001). Individuals with the MTHFR TT genotype had significantly higher serum tHcy concentrations than individuals with the CC and CT genotypes (p<0.001). The folate level of red blood cells was significantly increased in individuals with the TT genotype than in individuals with the CC genotype (p<0.05). Moreover, in the low vitamin group, the serum tHcy level was significantly correlated with the levels of folate (r=−0.334, p=0.001) and vitamin B12 (r=−0.212, p=0.046). ConclusionThe MTHFR C677T polymorphism, folate deficiency, and B12 deficiency were significantly associated with elevated serum tHcy levels. Among these three factors, folate deficiency had the greatest contribution to the serum tHcy concentration, followed by (in order of decreasing effect) MTHFR C677T and vitamin B12 deficiency. Thus, folic acid and vitamin B12 supplementation could help prevent diseases associated with tHcy accumulation, especially in individuals with the MTHFR 677TT genotype.

B vitamin supplementation improves cognitive function in the middle aged and elderly with hyperhomocysteinemia

Objective: An intervention study was performed to determine if supplement containing folic acid, vitamin B6, and vitamin B12 could improve cognitive function and lower homocysteine in middle-aged and elderly patients with hyperhomocysteinemia.Methods: One hundred and four participants with hyperhomocysteinemia were recruited in Tianjin, China, aged 55–94 years old. Fifty-seven individuals with hyperhomocysteinemia were included in the intervention group (vitamin B group, which received 800 µg/day of folate, with 10 mg of vitamin B6 and 25 µg of vitamin B12) and 47 patients in the placebo group. The endpoint was the improvement in cognitive function as evaluated by Basic Cognitive Aptitude Tests (BCATs). All parameters were measured before and after the treatment period of 14 weeks.Results: The BCAT total score and four sub-tests scores (digit copy, Chinese character rotation, digital working memory, and recognition of meaningless figure) of BCAT at 14 weeks significantly increased only for the vitamin B group. Serum total homocysteine (tHcy) levels significantly decreased in the intervention group, while serum concentrations of folate, vitamin B6, and vitamin B12 significantly increased in the intervention group.Conclusion: The results demonstrated that supplement containing folate, vitamin B6, and vitamin B12 in middle-aged and elderly patients with hyperhomocysteinemia could improve their cognitive function partly and reduce serum tHcy levels.

Heterozygous carriers of classical homocystinuria tend to have higher fasting serum homocysteine concentrations than non-carriers in the presence of folate deficiency

Many studies have reported that serum total homocysteine (tHcy) levels in cystathionine-beta-synthase (CBS) carriers are usually normal and only elevated after a methionine load. However, the amount of methionine required for a loading test is non-physiological and is never reached with regular feeding. Therefore, CBS carriers do not seem to be at an increased risk of cardiovascular diseases. However, the risk of cardiovascular diseases of CBS carriers with folate deficiency has not been studied. We recently found an extraordinarily high carrier rate (1/7.78) of a novel CBS mutation (p.D47E, c.T141A) in an Austronesian Taiwanese Tao tribe who live in a geographic area with folate deficiency. We evaluated if the CBS carriers tend to have higher fasting serum tHcy concentrations than non-carriers in presence of folate deficiency. The serum tHcy and folate levels before and after folate replacement were measured in 48 adult Tao carriers, 40 age-matched Tao non-carriers and 40 age-matched Han Taiwanese controls. The serum tHcy level of the Tao CBS carriers (17.9 ± 3.8 μmol/l) was significantly higher than in Tao non-carriers (15.7 ± 3.5 μmol/l; p < 0.008) and Taiwanese controls (11.8 ± 2.9 μmol/l; p < 0.001). Furthermore, a high prevalence of folate deficiency in the Tao compared with the Taiwanese controls (4.9 ± 1.8 ng/ml vs. 10.6 ± 5.5 ng/ml; p < 0.001) was also noted. Of note, the difference in tHcy levels between the carriers and non-carriers was eliminated by folate supplementation. (carriers:13.65 ± 2.13 μmol/l; non-carriers:12.39 ± 3.25 μmol/l, p = 0.321). CBS carriers tend to have a higher tHcy level in the presence of folate deficiency than non-carriers. Although many reports have indicated that CBS carriers are not associated with cardiovascular disease, the risk for CBS carriers with folate deficiency has not been well studied. Owing to a significantly elevated level of fasting tHcy without methionine loading, it is important to evaluate the risk of cardiovascular disease in CBS carriers with folate deficiency.

Tagging SNPs in the MTHFR Gene and Risk of Ischemic Stroke in a Chinese Population

Stroke is currently the leading cause of functional impairments worldwide. Folate supplementation is inversely associated with risk of ischemic stroke. Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism. The aim of this study is to examine whether genetic variants in MTHFR gene are associated with the risk of ischemic stroke and fasting total serum homocysteine (tHcy) level. We genotyped nine tag SNPs in the MTHFR gene in a case-control study, including 543 ischemic stroke cases and 655 healthy controls in China. We found that subjects with the rs1801133 TT genotype and rs1801131 CC genotype had significant increased risks of ischemic stroke (adjusted odds ratio (OR) = 1.82, 95% confidence interval (CI): 1.27–2.61, p = 0.004; adjusted OR = 1.99, 95% CI: 1.12–3.56, p = 0.01) compared with subjects with the major alleles. Haplotype analysis also found that carriers of the MTHFR CTTCGA haplotype (rs12121543-rs13306553-rs9651118-rs1801133-rs2274976-rs1801131) had a significant reduced risk of ischemic stroke (adjusted OR = 0.53, 95% CI: 0.35–0.82) compared with those with the CTTTGA haplotype. Besides, the MTHFR rs1801133 and rs9651118 were significantly associated with serum levels of tHcy in healthy controls (p < 0.0001 and p = 0.02). These findings suggest that variants in the MTHFR gene may influence the risk of ischemic stroke and serum tHcy.

Homocysteine-Lowering Therapy and Risk of Recurrent Stroke, Myocardial Infarction and Death: The Impact of Age in the VISP Trial

Background: Clinical trials have failed to show a benefit of B vitamin therapy in reducing composite outcomes of cardiovascular death, myocardial infarction, and stroke among stroke survivors with elevated total serum homocysteine (tHcy) levels. Recent post hoc analyses have shown that numerous factors including age, baseline tHcy levels, folic acid fortification of grains, B₁₂ status, renal function, comorbidities, and medications may modify the effect of B vitamin therapy on vascular risk in individuals with high tHcy. It remains possible that tHcy-lowering therapy may reduce cardiovascular risk in certain subgroups of stroke survivors. Post hoc subgroup analysis of the Heart Outcomes Prevention Evaluation-2 randomized controlled trial, which randomized participants with known cardiovascular disease to tHcy-lowering therapy or placebo, revealed larger treatment benefit for patients aged younger than 69 years; however, that analysis did not control for other factors. The aim of this study was to determine the effect of age on the impact of tHcy-lowering therapy for reducing vascular risk after stroke while controlling for other factors known to modify the effect of tHcy and tHcy-lowering therapy on vascular risk. Methods: In this post hoc analysis of the Vitamin Intervention for Stroke Prevention (VISP) trial, a randomized controlled trial of tHcy lowering for secondary stroke prevention, we excluded individuals who had poor renal function (glomerular filtration rate <47; the 10th percentile) or were treated with vitamin B₁₂ injections. We assessed the effects of high-dose vitamin replacement on primary (stroke, myocardial infarction, or death) and secondary (stroke) outcomes, after stratifying by age (< vs. ≥ median age, 67 years) and adjusting for demographic and clinical factors. Results: This subgroup consisted of 2,993 individuals. Among individuals older than 67 years, high-dose vitamin therapy was associated with reduced risk of stroke, myocardial infarction or death (adjusted HR 0.76, 95% CI 0.58-0.99) and a trend towards reduced likelihood of stroke (adjusted HR 0.86, 95% CI 0.59-1.25). High-dose vitamin therapy did not impact outcomes among individuals younger than 67 years. Conclusions: In this post hoc subgroup analysis of the VISP trial, age modified the association between B vitamin therapy and recurrent vascular risk among stroke survivors with elevated serum tHcy levels. Older individuals with stroke were more likely to benefit from B vitamin therapy than younger individuals. These findings can help inform the future design of clinical trials of tHcy-lowering therapy for cardiovascular risk reduction after stroke.

Association of tagging SNPs in the MTHFR gene with risk of type 2 diabetes mellitus and serum homocysteine levels in a Chinese population.

Diabetes is a global public health crisis, and the prevalence is increasing rapidly. Folate supplementation is proved to be effective in reducing the risk of diabetes or improving its symptoms. Methylenetetrahydrofolate reductase is an important enzyme involved in folate metabolism. The aim of this study is to examine whether polymorphisms in the MTHFR gene are associated with risk of type 2 diabetes mellitus (T2DM) and fasting total serum homocysteine (tHcy) levels. We genotyped nine tagging SNPs in the MTHFR gene in a case-control study, including 595 T2DM cases and 681 healthy controls in China. We found that C allele of rs9651118 had significant decreased risk of T2DM (adjusted odds ratio (OR) = 0.69, 95% confidence interval (CI): 0.55–0.87, P = 0.002) compared with T allele. Haplotype analysis also showed that MTHFR CTCCGA haplotype (rs12121543-rs13306553-rs9651118-rs1801133-rs2274976-rs1801131) had significant reduced risk of T2DM (adjusted OR = 0.71, 95% CI: 0.58–0.87, P = 0.001) compared with CTTTGA haplotype. Besides, the MTHFR rs1801133 was significantly associated with serum levels of tHcy in healthy controls (P = 0.0002). These associations were still significant after Bonferroni corrections (P < 0.0056). These findings suggest that variants in the MTHFR gene may influence the risk of T2DM and tHcy levels.

Lamotrigine Decreased Hippocampal Damage and Improved Vascular Risk Markers in a Rat Model of Pentylenetetrazole Induced Kindling Seizure

Various antiepileptic drugs (AEDs) especially enzyme-inducing AEDs might be associated with increased vascular risk, through impairment of the endogenous antioxidative ability which may trigger oxygen-dependent tissue injury. Lamotrigine (LTG) a non-enzyme-inducing AED has scarce information regarding its effects on oxidative stress. The present study aimed to study the possible modulation of vascular risk factors of epileptogenesis by LTG, in a rat model of kindling seizure induced by pentylenetetrazole (PTZ). Four groups of male Wister rats were used; vehicle control group, PTZ group (alternate day PTZ, 30 mg/kg, i.p), LTG/PTZ group (LTG 20 mg/kg/day p.o and alternate day PTZ) and LTG group. The study period was 5 weeks. Lipoproteins and total homocysteine (tHcy), malondialdehyde (MDA) and reduced glutathione (GSH) were measured. Aortic endothelial function study and histopathological examination of the rats' brains, aortas and coronaries were conducted. Serum total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C), tHcy, MDA, GSH levels were significantly higher in epileptic rats than normal controls rats. A decrease in HDL-cholesterol with high atherosclerotic index was also demonstrated. The administration of LTG improved the PTZ-kindled seizures. It produced a significant decrease in TC, TG and LDL-cholesterol, MDA, aortic GSH and increase in HDL-cholesterol with no significant effect on serum GSH and tHcy levels. LTG improved endothelium-dependent relaxation, decreased hippocampal neurodegenerative changes and atherosclerotic changes of aortas and coronaries. LTG decreased seizures severity, hippocampal damage and improved vascular risk markers in this rat model of kindling seizures.

Low erythrocyte catalase enzyme activity is correlated with high serum total homocysteine levels in tunisian patients with acute myocardial infarction

BackgroundAn imbalance between pro-oxidants and antioxidant systems has been suggested to be implicated in the physiopathology of acute myocardial infarction (AMI). We aimed to evaluate the antioxidant capacity in Tunisian patients and to assess the possible relationship between erythrocyte catalase enzyme activity and hyperhomocysteinaemia.Methods108 patients with AMI and 81 healthy subjects were enrolled in this study. Catalase erythrocyte enzyme activity was determined spectrophotometrically whereas “total antioxidant status” (TAS) concentration was measured by a commercially available method. Serum total homocysteine (tHcy) level was determined by a fluorescence polarization immunoassay (FPIA). Lipid peroxidation was measured with a fluorimetric method as “thiobarbituric acid reactive substances” (TBARS).ResultsCompared with healthy subjects, patients with AMI had significantly lower catalase activity (P<0.001), TAS concentrations (P<0.001), and significantly higher serum tHcy (P<0.001) and TBARS levels (P<0.001). Erythrocyte catalase enzyme activity was negatively correlated with serum tHcy and TBARS while serum tHcy and TBARS were in positive correlation. Furthermore, the unbalance between pro-oxidants and antioxidants seems to be more aggravated in patients with Q wave AMI compared to patients with non-Q wave AMI.ConclusionOur results suggest the involvement of hyperhomocysteinaemia in the drop of erythrocyte catalase activity related to myocardial ischemia reperfusion. Hyperhomocysteinaemia may increase the myocardial wall dysfunction under ischemia reperfusion by excessive production of reactive oxygen species which is made evident by increased lipid peroxidation.Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1623509866881834

Homocysteine levels and cognitive function scores measured with MMSE and BCAT of middle-aged and elderly subjects in Tianjin City.

China is proceeding into the aging society. There are near 6 million elderly suffering senile dementia,while cognitive impairment is an important clinical feature in dementia. The factors involved in cognitive dysfunction in the middle-aged and the elderly persons were investigated. Cross-sectional study. Community dwellers and nursing home residents in Tianjin, China. Total of 662 subjects(284 men and 378 women) aged 55-93. A designed questionnaire was used to collect their demographic data, information of disease and medication, and life style. Mini-mental state examination (MMSE) and Basic Cognitive Aptitude Tests (BCAT) software were applied to evaluate their cognitive function. Serum total homocysteine (tHcy) level was quantified by enzyme conversion method. A multiple linear stepwise regression analysis was applied to find the influencing factors of cognitive function. The average serum tHcy concentrations was 15.95±7.29 μmol/L, while the prevalence of hyperhomocysteinemia (HHE) was 45.4%. The average serum tHcy level and prevalence of HHE were higher in men than those in women after ruling out the age differences. The mean MMSE and BCAT scores were 26.74±2.71 and 50.26±18.84 respectively. The BCAT score was negatively correlated with age and positively correlated with education. Multiple linear stepwise regression equations showed that the P value was less than 0.001, the BCAT regression equation showed that the R2=0.453. Serum tHcy concentration was negatively correlated with total scores of BCAT, digit copy, Chinese character comparison, mental arithmetic, Chinese character rotation and recall answer of mental arithmetic test. Total scores of BCAT were negatively correlated with education, inhabitancy, serum tHcy concentration and age. In addition, Chinese character rotation was correlated with tea consumption. Remembrance and recognition of dual words and nonsense figures was correlated with income level. Hyperhomocysteinemia is associated with cognitive impairment in the middle-aged and the elderly persons in Tianjin. The BCAT scores could well represent the detailed cognitive function in elderly and negatively correlate with age, but positively correlated with education level. Serum tHcy concentration was negatively correlated with total BCAT scores.

Association of the C677T Polymorphism in the MTHFR Gene with Risk of Oral Squamous Cell Carcinoma in South Indian Population

Background: The C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene is associated with reduced enzyme activity, and a significant increase in serum homocysteine (Hcy) concentration. MTHFR C677T polymorphism was likely to play an important role in the susceptibility to OSCC. Methods: In this case-control study, we genotyped 150 OSCC patients and 150 controls, using a PCR-RFLP method. The serum total homocysteine levels were quantitatively detected using commercial enzyme immunoassay (EIA) kits from AxisShied Diagnostics Ltd, UK. Results: In the present study heterozygous CT genotype was found statistically significantly more prevalent in patients than in controls [OR 3.38, 95%CI 146-7.79, p-value 0.004], whereas TT genotype was not statistically significant [OR 2.01, 95%CI 0.18-22.4, p-value 0.05]. CC genotype may be protective for OSCC [OR 0.30, 95%CI 0.13-0.67, P-value 0.003]. The mean serum tHcy levels (mmol/L) 15.0 were higher in cases in all three CC (26.81±7.51), CT (29.26±7.67) and TT (48.85±28.07) genotypes when compared to CC (17.85±2.18), CT (17±1.0) and TT (0) with controls. However, significant variation of homocysteine levels was not observed between the genotypes of OSCC patients and controls. Conclusion: The results of the present study indicate that the frequency of MTHFR 677 ‘T’ allele is rare and CT genotype may be associated with OSCC risk. However, the polymorphisms in the MTHFR gene (677C/T) that are reported to modulate homocysteine levels were not associated with OSCC.

Plasma ω-3 fatty acid levels negatively and ω-6 fatty acid levels positively associated with other cardiovascular risk factors including homocysteine in severe obese subjects.

Obesity and homocysteine (tHcy) are important risk factors for cardiovascular diseases (CVD). Plasma omega-3 fatty acids (ω-3 FAs) and omega-6 fatty acids (ω-6 FAs) are essential fatty acids with diverse biological effects in human health and disease. We have investigated the relation of plasma ω-3 FAs and ω-6 FAs levels with other cardiovascular risk factors including tHcy in severe obese subjects. This study was performed on 96 severe obese and 65 normal weight subjects. Plasma fatty acid composition was measured by GC/MS and serum tHcy level was measured by HPLC methods. There were no differences between groups in terms of concentrations of serum tHcy, plasma ω-3 FAs, ω-6 FAs and ω-3/ω-6 ratio, whereas serum vitamin B-12 (p<0.01) and folic acid (p<0.05) levels were lower than those of the normal weight subjects. Homocysteine positively correlated with ω-6 FAs and negatively correlated with ω-3 FAs in severe obese and normal weight subjects. Serum vitamin B-12 positively correlated with ω-3 FAs (p<0.01) and ω-3/ω-6 ratio (p<0.01) and negatively correlated with ω-6 FAs (p<0.05) in severe obese subjects. Serum folic acid positively correlated with ω-3 FAs (p<0.01) in severe obese subjects. Our results suggest an association between the plasma ω-3 FAs and ω-6 FAs and serum tHcy concentrations in severe obese and normal weight subjects. Low levels vitamin B-12 and folic acid may have been responsible for the elevated tHcy levels in severe obese subjects, increasing the risk for future development of cardiovascular diseases.

Traditional Eating Habits and Level of Homocysteine in the Acute First-Ever Ischaemic Stroke

Background: Meal with high-fat content represents a common and increasing habit in general population in the Macedonia. Contribution of homocysteine and meal with high-fat content in the acute phase of first-ever ischaemic stroke (AFIS) due to the different dietary habits remains unclear. Aim: Our aims/hypothesis was comparison of serum total homocysteine (tHcy) level and dietary habits in patients with AFIS and in controls due to non-consuming (non-users) or consuming (users) meat with high content of fats that can be regarded as traditional eating habits influenced by religion dietary restrictions from Lower Pollog populations. Materials and Methods: From initially 847 patients hospitalized from September 2008 to August 2010in neurology department, only 231 patients with diagnostic entity-AFIS and 194 healthy subjects were evaluated in this study. Serum tHcy was measured on admission and dietary history was noted. Results: In the overall pooled estimate, for all included study participants, serum tHcy level in the acute phase of disease and frequency of users are similar in patient with AFIS and in controls, but non-users mostly was dispose to AFIS and hyperhomocysteinemia. Conclusion: Meat with high-fat content is very often combined with tHcy-increasing effects at users. Because the regression coefficient of linear regression model with users as variable, adjusting for age, gender and serum tHcy of patients with AFIS was not confirmed the statistical significance of previous pretesting factors by cross tabulation model our research could not confirm that hyperhomocisteinemia and meat with high-fat content are the only reason for cause of AFIS.

Relationship Between Genetic Polymorphisms of Methylenetetra hydrofolate Reductase (C677T, A1298C, and G1793A) as Risk Factors for Idiopathic Male Infertility

The human methylenetetrahydrofolate reductase (MTHFR) gene plays a crucial role in folate metabolism. Data regarding the influence of MTHFR gene polymorphisms on male fertility status are scarce and conflicting. We determined associations between 3 MTHFR gene polymorphisms (C677T, A1298C, and G1793A), serum folate, and total homocysteine (tHcy) levels, with male fertility status and semen parameters. MTHFR genotypes were determined using polymerase chain reaction restriction fragment length polymorphism (PCR-RLFP) technique and serum tHcy, folate, and vitamin B12 concentrations were measured in 164 men with idiopathic infertility and 328 healthy participants. There was a significant difference in genotype frequency distribution of MTHFR C677T polymorphism between infertile patients and controls (P = .004). The 677T allele carriers (TC or TT) had a significantly increased risk of infertility compared with the CC homozygotes (odds ratio [OR] 1.60, 95% confidence interval [CI] 1.21-2.75, and OR = 2.68, 95% CI = 1.84-3.44, respectively), in a logistic regression model after adjustment for confounding factors. Men with the 677T, 1298C, and 1793G alleles showed significantly higher serum tHcy and lower folate levels (all Ps < .01). We found a positive correlation between serum folate concentrations and sperm density (r = .74, P = .001), percentage of sperm with progressive motility (r = .68, P = .001), as well as percentage of sperm with normal morphology (r = .72, P = .001). MTHFR C677T polymorphism is associated with an increased risk of idiopathic male infertility. Further study on the biologic role that this polymorphism plays in the development of infertility may lead to better understanding of the etiology of impaired spermatogenesis.

Folate, vitamin B12 and total homocysteine levels in Arab adolescent subjects: Reference ranges and potential determinants

Background & AimsElevated circulating fasting total homocysteine (tHcy) concentration is associated with an increased risk of occlusive vascular disease in adults. Important determinants of tHcy levels are folate, vitamin B12 and vitamin B6. This study aimed to investigate age, gender, and body mass as determinants of folate, vitamin B12 and tHcy levels in Arab older children and adolescents and to propose population, gender and age-specific reference ranges for these biomarkers. Methods & Results774 (316 boys, 458 girls) healthy 10–19 yr olds attending secondary schools in Kuwait were assessed for anthropometry and fasting blood levels of Hcy, folate and vitamin B12. The mean (95% CI) serum levels of tHcy, folate and vitamin B12 were respectively 6.57 μmol/L (6.42–6.73), 16.0 ng/ml (15.6–16.3) and 354.3 pg/ml (343.0–365.7). Boys had significantly higher tHcy and folate concentrations than the girls, although vitamin B12 levels were greater in the latter. Folate and vitamin B12 levels decreased significantly with age, while correspondingly, tHcy levels increased, with mean values (μmol/L) for boys (6.71; 8.25) and girls (5.36; 6.67) aged 10–14 yr and 14–19 yr respectively. Bivariate and multivariate analyses with adjustment for confounders such as age, gender, need for dietary control and socio-demographic variables indicated that the independent determinants of levels of tHcy were age, gender and body mass. ConclusionThere is an age-related increase in tHcy in adolescents reflecting decreased levels of folate and vitamin B12, with the suggestion that age-related reference ranges for these biomarkers be used. These observations may have implications for prevention of future atherogenic disease.

Serum asymmetric dimethylarginine (ADMA), homocysteine, vitamin B12, folate levels, and lipid profiles in epileptic children treated with valproic acid

Recent reports have demonstrated elevated serum homocysteine (Hcy) levels in children receiving valproic acid (VPA) therapy. Elevated Hcy levels might play a potential role in the resistance to antiepileptic drugs, and might lead to an increased risk for a vascular disease. It has been reported that elevated total homocysteine (tHcy) levels are associated with elevated asymmetric dimethylarginine (ADMA) levels, which are factors that may be better indicators of endothelial dysfunction compared to serum homocysteine levels, because they are less sensitive to changes, such as fasting status, physical activity, and other factors. In this study, we aim to evaluate serum ADMA, Hcy, lipid, folate, and vitamin B₁₂ levels in epileptic children, receiving VPA monotherapy. Forty-four epileptic children, receiving VPA monotherapy for at least 6 months and 28 healthy children aged between 4 and 16 years, were recruited. Serum lipids, lipoproteins, folate, vitamin B₁₂, Hcy, and ADMA levels were analyzed in both study groups. Serum Hcy, ADMA, and vitamin B₁₂ levels were higher in patients than in controls (p < 0.001 for tHcy and ADMA levels; p < 0.05 for vitamin B₁₂ levels); however, serum lipid, lipoprotein, and folate levels were similar. According to the duration of epilepsy, serum tHcy, ADMA, and triglyceride (TG) levels were higher in patients with epilepsy for ≥ 2 years than in patients with epilepsy for < 2 years (p < 0.001 for serum ADMA levels, p < 0.01 for tHcy levels, and p < 0.05 for serum TG levels). Similarly, with respect to the duration of VPA therapy, serum tHcy, ADMA, and TG levels were higher in patients who had received VPA therapy for more than 2 years (p < 0.001 for serum ADMA levels, p < 0.05 for serum tHcy levels, p < 0.01 for TG levels). Serum ADMA levels were significantly higher in patients receiving VPA at the dose of 25-30 mg/kg/day than in those receiving 20 mg/kg/day (p < 0.01). In conclusion, our study found increased serum ADMA levels and increased tHcy levels in epileptic children receiving VPA monotherapy. Increased serum ADMA levels were demonstrated in epileptic children who have had a seizure history greater than 2 years, and have used VPA therapy for more than 2 years, and have received higher doses of VPA. Routine monitoring of serum ADMA and tHcy levels might have beneficial effects for patients receiving long-term VPA therapy, especially in children who have other potential risk factors for vascular diseases. Further studies are needed to investigate serum ADMA and Hcy levels, and the presence of vascular disease, as well as the potential interactions between serum ADMA levels and seizure control.

Genetic susceptibility of methylenetetrahydrofolate reductase (MTHFR) gene C677T, A1298C, and G1793A polymorphisms with risk for bladder transitional cell carcinoma in men

We performed a case-control study of 158 bladder transitional cell carcinoma (TCC) cases and 316 controls to investigate the association between methylenetetrahydrofolate reductase (MTHFR) C677T, A1298G, and G1793A polymorphisms and bladder cancer susceptibility by polymerase chain reaction restriction fragment length polymorphism (PCR-RLFP) technique. The controls were frequency-matched to the cases by age (± 5 years), ethnicity, and smoking status. We also measured serum levels of total homocysteine (tHcy), folate, and vitamin B12. It was found that the 1298AC (odds ratio, OR = 3.74; 95% confidence interval, CI = 2.34-5.47; P = 0.001) and 1298CC (OR = 3.46, 95% CI = 2.37-5.52; P = 0.001) genotypes of MTHFR A1298C were significantly associated with increased risk of bladder TCC. The MTHFR C677T and G1793A polymorphisms were not associated with bladder TCC. After stratification for grade and stage, we observed that the 677TT (OR = 4.47, 95% CI = 2.74-6.72; P = 0.001) and MTHFR 1298CC (OR = 4.78, 95% CI = 2.82-6.89; P = 0.001) genotypes of MTHFR were associated with increased risk of muscle-invasive bladder TCC. We also found that the MTHFR 677CT+1298AA genotypes were associated with an approximately 70% reduction in risk of bladder cancer (OR = 0.31; 95% CI = 0.15-0.68) compared to the combined referent genotype. There were 8 haplotypes and 16 haplotype genotypes based on these three variants. When we used the haplotypes and assumed that the 677T, 1298C, and 1793G alleles were risk alleles, the adjusted odds ratios increased as the number of risk alleles increased: 1.00 for 0-1 variant, 1.88 (1.4-2.7) for any two risk alleles and 2.07 (1.6-2.8) for any three risk alleles. Serum tHcy levels were significantly higher in carriers of the 677T, 1298C, and 1793G alleles compared to noncarriers (all P < 0.01). There was no significant correlation between serum levels of tHcy and folate and bladder cancer risk. Further studies in larger samples size and different ethnicity are required to confirm our findings.

Role of PERK/eIF2a signaling pathway in hepatocyte apoptosis of alcoholic liver injury rats

To investigate the role of PERK/eIF2alpha signaling pathway in hepatocyte apoptosis of alcoholic liver injury rats. Rat models with ethanol-induced liver injury were successfully developed by gastric gavage with ethanol-corn oil mixtures for 12 weeks. At different time points (4, 6, 10, 12 week), liver pathology was dynamically observed. The hepatocyte apoptosis was quantitatively analyzed by Annexin V-FITC/PI double-labeled flow cytometry, the serum total homocysteine (tHCY) level was detected by ELISA and the expressions of eIF2a, p-eIF2a, GRP78/Bip, GRP94, caspase-3 and caspase-12 in liver were examined using Real-time PCR and Western blot. Typical acute liver injury and chronic liver injury were observed at week 4 and week 12 respectively. The hepatocyte apoptosis rates in 6-week model rats significantly increased compared with normal rats (P value less than 0.05), and the degree of hepatocyte apoptosis continued to increase with the modeling time, and the percentages of early and total apoptosis reached 26% and 29% at week 12. From week 6 to week 12, the serum tHCY levels in model rats were obviously higher than in normal rats (P value less than 0.01). Since week 4, eIF2a protein phosphorylation in model rat livers remarkably elevated compared with that in normal rat livers (P value less than 0.01), and at week 12 the peIF2a protein expression in model rat livers increased by 2.81-fold. Since week 4 the expressions of GRP78/Bip, GRP94, caspase-12 and caspase-3 mRNA and protein in model rat livers showed a significant increase as compared to normal rat livers, and at week 12, these gene and protein levels increased 4.70, 12.95, 3.83, 4.05 fold and 3.93, 6.93, 9.88, 3.31 fold, respectively (P value less than 0.01). Activation of PERK/eIF2a signaling pathway contributes to the occurrence and development of hepatocyte apoptosis in alcoholic liver injury rats and it might be as a potential target for therapeutic applications in alcoholic liver diseases.