Total Homocysteine Research Articles

Abstract 12719: The Association of High Vitamin B12 With Mortality Risks and Related Metabolisms Among Hypertensive Population

Background: The association of high serum vitamin B12 (B12) with mortality risks is not well studied, and its independence from related metabolites needs to be disentangled. This study aims to explore the association of high serum B12 levels with all-cause mortality and its interaction with serum folate and plasma total homocysteine (tHcy) among Chinese adults with hypertension. Methods: This large observational study obtained data from the China Stroke Primary Prevention Trial (CSPPT), a multi-center RCT. The study sample consisted of 9,695 hypertensive adults who were not exposed to B vitamin supplements at baseline and during follow-up. The primary outcome was all-cause mortality, and the secondary outcome was cardiovascular mortality. Patients were stratified by B12 tertiles, and previously published cutoffs: B12 < 299.52 pg/ml included patients with circulating B12 deficiency and sub-optimal deficiency; B12 < 349.69 pg/ml with concomitant elevated tHcy determines B12 metabolic deficiency; B12 ≥ 349.69 ng/ml refers to those who are free from both circulating and metabolic B12 deficiency. Results: During the median follow-up time of 4.5 years, 284 deaths occurred. Compared to individuals with lower B12 levels, those with elevated B12 showed increased risk of all-cause mortality (hazard ratio (HR), 1.41 95%CI 1.07-1.85) and cardiovascular mortality (HR, 3.01; 95% CI 1.30-7.01). The association between elevated B12 and all-cause mortality risk appears robust in all tested subgroups. After excluding those with potential B12 metabolic deficiency, elevated B12 remains significantly and independently associated with all-cause mortality (HR, 1.36 95%CI 1.05, 1.76) and cardiovascular mortality (HR, 2.44 95%CI 1.15, 5.18). The Bayesian kernel machine regression results showed that higher B12 is associated with increased all-cause mortality risk independent of baseline folate and tHcy. Conclusion: Among Chinese adults with hypertension, elevated B12 levels is associated with increased risk of all-cause mortality, independent of baseline folate, tHcy, and other traditional risk factors. These findings, if further confirmed, have important implications for nutritional counseling and clinical recommendations on B vitamin therapy.

Association between oxidative stress, antioxidant enzymes, and homocysteine in patients with polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is a prevalent health condition that commonly affects adolescent girls and young women. The purpose of this study was to evaluate the correlation between levels of total glutathione (TG), reduced glutathione (GSH), superoxide dismutase (SOD), lipid peroxidation, and homocysteine with PCOS. This study employed a cross-sectional case-control design, involving a target population of 305 Sudanese females. Among them, 205 individuals were categorized as cases, and 100 served as controls. The TG, GSH, SOD, lipid peroxidation, and homocysteine levels were measured in the serum of study participants through enzyme-linked immunosorbent essay. Total glutathione (1,174.5 ± 271.4 vs. 986.1 ± 191.5, p = 0.01), GSH (801.3 ± 132.2 vs. 748.6 ± 103.1, p = 0.007), SOD (225.2 ± 57.8 vs. 195.5 ± 49.6, p = 0.009), lipid peroxidation (3.4 ± 1.1 vs. 2.4 ± 0.7, p = 0.03), and homocysteine (14.9 ± 2.1 vs. 13.5 ± 1.6, p = 0.04), showed significant differences between the two groups (cases vs. controls). A moderate positive correlation between TG, GSH, SOD, lipid peroxidation, homocysteine, BMI, age, and duration of PCOS was observed. Furthermore, a strong positive correlation between BMI, age, and duration of PCOS was noted within the patient group. In conclusion, this study demonstrates that patients with PCOS have elevated levels of TG, GSH, SOD, lipid peroxidation, and homocysteine compared to the control group. These findings suggest a potential association between PCOS and oxidative stress, lipid metabolism, and homocysteine pathways. Moreover, the observed positive correlation with BMI, age, and duration of PCOS indicates the importance of these factors in disease progression.

Longitudinal changes of oxidative stress and PON1 lactonase activity and status in older pregnant women undergoing assisted reproductive technology: a prospective nested case-control study

BackgroundChildbearing in women with advanced maternal age (AMA) has increased the need for artificial reproductive technology (ART). ART and oxidative stress are associated with many pregnancy complications. Paraoxonase (PON) 1 is one of the key components responsible for antioxidative activity in high-density lipoprotein (HDL). This study aimed to investigate the longitudinal changes of oxidative stress and PON1 lactonase activity and status in older women undergoing ART.MethodsThis prospective nested case-control study included 129 control and 64 ART women. Blood samples were obtained respectively at different stages of pregnancy. PON1 level and lactonase activity were assessed using 7-O-diethylphosphoryl-3-cyano-4-methyl-7-hydroxycoumarin (DEPCyMC) and 5-thiobutyl butyrolactone (TBBL) as a substrate, respectively. A normalized lactonase activity (NLA) was estimated based on the ratio of TBBLase to DEPCyMCase activity. Serum total oxidant status (TOS), total antioxidant capacity (TAC), malondialdehyde (MDA), homocysteine (HCY), PON1 C-108T and Q192R genetic polymorphisms, and metabolic parameters were analyzed.ResultsLactonase activity and level of PON1 gradually decreased with pregnancy progression, while glycolipid metabolism parameters and TAC levels increased with pregnancy progression or significantly raised during the 2nd and 3rd trimesters, and NLA of PON1, TOS, OSI, MDA, and HCY significantly increased before delivery in the ART and control groups. Compared with the control women, the ART women had substantially higher or relatively high lactonase activity and NLA of PON1 and TAC during pregnancy; higher triglyceride (TG), total cholesterol, low-density lipoprotein cholesterol, atherogenic index, apolipoprotein (apo) B, and apoB/apoA1 ratio in the 1st trimester; and higher fasting glucose, fasting insulin, homeostatic model assessment of insulin resistance, and TG levels before delivery. No significant differences were found in the frequencies of PON1 C-108T and Q192R genotypes and alleles between the ART and control groups.ConclusionsWomen with AMA undergoing ART had higher TAC, PON1 lactonase activity, and PON1 NLA than control women, suggesting increased compensatory antioxidant capacity in ART women, thus showing higher sensitivity to oxidative stress-related injury and diseases.

Vitamin B12 and Folate Status in Pregnant Females and Their Infants in Norway: Secondary Analysis from the Mommy’s Food Study

BackgroundVitamin B12 and folate are essential micronutrients important for normal infant growth and development. ObjectivesThe aims were to describe vitamin B12 and folate status in pregnant females and their infants according to commonly used status cutoffs and examine the associations between maternal status, maternal supplement use, and breastfeeding and infant status. MethodsPregnant females were recruited at 18 wk gestation in Bergen, Norway. Maternal vitamin B12 and folate status were measured at gestational weeks 18 (n = 136) and 36 (n = 116), and infant status was measured at ages 3 (n = 73) and 6 (n = 74) mo. ResultsAt gestational weeks 18 and 36, respectively, 4.4% and 2.6% of the mothers had plasma cobalamin concentrations <148 pmol/L, 0.7% and 6.9% had methylmalonic acid (MMA) concentrations >0.26 μmol/L, and 3.7% and 30% had folate concentrations <10 nmol/L. None of the females had total homocysteine (t-Hcy) concentrations >13 μmol/L or 3 combined indicator of vitamin B12 (cB12) < −0.5. At 3 and 6 mo, respectively, 4.1% and 5.4% of the infants had cobalamin concentrations <148 pmol/L, 63% and 74% had t-Hcy concentrations >6.5 μmol/L, 59% and 66% had MMA concentrations >0.26 μmol/L, and 47% and 60% had cB12 > −0.5. None of the infants had folate concentrations <10 nmol/L. Several of the vitamin B12 biomarkers in infants were associated with maternal vitamin B12 status during pregnancy. Breastfed infants had lower vitamin B12 status (as indicated by plasma cobalamin, t-Hcy, and cB12) than nonbreastfed infants at both 3 and 6 mo. Use of supplements during pregnancy was associated with better vitamin B12 status among infants at 3 and 6 mo, as indicated by infants’ cobalamin and t-Hcy concentrations. ConclusionsSubclinical vitamin B12 deficiency among infants was common and associated with maternal vitamin B12 status during pregnancy and breastfeeding. Among the mothers, an increase in biochemical folate deficiency was discovered toward the end of gestation. Further studies are needed to investigate clinical consequences.This trial was registered at clinicaltrials.gov as NCT02610959.

The association of lipid metabolism and sarcopenia among older patients: a cross-sectional study

Sarcopenia has become a heavy disease burden among the elderly. Lipid metabolism was reported to be involved in many degenerative diseases. This study aims to investigate the association between dysregulated lipid metabolism and sarcopenia in geriatric inpatients. This cross-sectional study included 303 patients aged ≥ 60, of which 151 were diagnosed with sarcopenia. The level of total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), homocysteine (HCY), BMI, and fat percentage, were compared between sarcopenia and non-sarcopenia patients. The Spearman correlation coefficient was used to estimate the association between sarcopenia and the level of lipid metabolism. To determine risk factors related to sarcopenia, a multivariate logistic regression analysis was carried out. Risk prediction models were constructed based on all possible data through principal component analysis (PCA), Logistic Regression (LR), Support Vector Machine (SVM), k-Nearest Neighbor (KNN), and eXtreme Gradient Boosting (XGboost). We observed rising prevalence of sarcopenia with increasing age, decreasing BMI, and fat percentage (p < 0.001, Cochran Armitage test). Multivariate logistic regression analysis revealed sarcopenia’s risk factors, including older age, male sex, lower levels of BMI, TC, and TG, and higher levels of LDL and HCY (p < 0.05). The sarcopenia risk prediction model showed the risk prediction value of sarcopenia, with the highest area under the receiver operating curve (AUC) of 0.775. Our study provided thorough insight into the risk factors associated with sarcopenia. It demonstrated that an increase in lipid metabolism-related parameters (BMI, TG, TC), within normal reference ranges, may be protective against sarcopenia. The present study can illuminate the direction and significance of lipid metabolism-related factors in preventing sarcopenia.

The Epidemiology of Deficiency of Vitamin B12 in Preschool Children in Turkey.

Background: Vitamin B12 is a water-soluble vitamin with important cellular functions; it is an essential vitamin. The aim of this study is to determine the B12 levels of children in the period from the 6th month when they start taking additional foods to the age of seven (preschool children) and the risk factors affecting them. Methods: One hundred pediatric patients aged 6-72 months who were diagnosed with vitamin B12 deficiency and their parents who agreed to attend Istanbul Atlas University, Medical Faculty, "Medicine Hospital" Pediatric Clinic between September 2022 and June 2023 were prospectively included in this study. Results: B12 deficiency was significantly higher in the 6-11 (25%)-month group than in the 12-23 (5.8%)- and 24-47 (2.8%)-month groups. Homocysteine levels were highest in those with insufficient B12 levels compared to the other groups. There was no statistically significant difference in weekly dairy and meat consumption levels between age groups. B12 levels were lower in the 6-11-month group than in the other groups. Homocysteine levels were highest in those with insufficient B12 levels (<200 pg/mL (148 pmol/L)). Folic acid levels were lower in the 24-47-month and 48-72-month groups than in the 6-11-month and 12-23-month groups. Conclusions: The results obtained in this study showed that low vitamin B12 and increased homocysteine levels seem to be important risk factors in preschool children, especially from the 6th month when they start consuming additional foods. The diagnosis of B12 deficiency can be confirmed by elevated serum total homocysteine levels, which are evidence of functional cobalamin deficiency.

The effects of folinic acid and l-methylfolate supplementation on serum total homocysteine levels in healthy adults

Hyperhomocysteinemia is recognized as a risk factor for several diseases and conditions. The aim of this study was to investigate and compare the efficacy of two total homocysteine (tHcy)-lowering treatments including folinic acid or l-methylfolate in healthy Greek adults. Two hundred and seventy-two healthy Greek adults (143 men, 129 women; mean age±SD: 43.0±15.3 years), with serum tHcy levels ≥10μmol/L received randomized folinic acid ("Folinic acid Group") or l-methylfolate ("l-methylfolate Group") orally for three months. All subjects with serum cobalamin (Cbl) levels <300pg/mL additionally received 1mg hydroxycobalamine intramuscularly twice a week for the first month only. Serum folate, Cbl and tHcy levels were determined using immunoassays methods at the beginning and the end of the study period. The MTHFR C677T and MTHFR A1298C gene polymorphisms were genotyped using polymerase chain reaction and reverse hybridization. At the end of the 3-month intervention period, the levels of serum folate and Cbl increased significantly, whereas the levels of serum tHcy decreased significantly in the two groups. The individuals with MTHFR 677TT genotype had a significantly higher reduction in serum tHcy levels than the individuals with the MTHFR 677CC or MTHFR 677CT genotypes. Although the "Folinic acid Group" had a considerably higher increase in their serum folate levels (but not Cbl) than the "l-methylfolate Group", the reduction of serum tHcy levels between the two groups was not substantially different. The individuals with MTHFR 677CT genotype had a statistically significant higher reduction in serum tHcy levels when supplemented with folinic acid rather than l-methylfolate. The administration of folinic acid compared to l-methylfolate caused a higher increase of serum folate levels but no difference in the reduction of serum tHcy levels. The reduction of serum tHcy levels was influenced by the existence of MTHFR C677T and not MTHFR A1298C gene polymorphisms. The individuals with MTHFR 677CT genotype appear to benefit more by folinic acid than l-methylfolate supplementation.

Atorvastatin rescues hyperhomocysteinemia-induced cognitive deficits and neuroinflammatory gene changes

BackgroundEpidemiological data suggests statins could reduce the risk of dementia, and more specifically, Alzheimer’s disease (AD). Pre-clinical data suggests statins reduce the risk of dementia through their pleiotropic effects rather than their cholesterol lowering effects. While AD is a leading cause of dementia, it is frequently found co-morbidly with cerebral small vessel disease and other vascular contributions to cognitive impairment and dementia (VCID), which are another leading cause of dementia. In this study, we determined if atorvastatin ameliorated hyperhomocysteinemia (HHcy)-induced VCID.MethodsWild-type (C57Bl6/J) mice were placed on a diet to induce HHcy or a control diet each with or without atorvastatin for 14 weeks. Mice underwent novel object recognition testing before tissue collection. Plasma total cholesterol and total homocysteine as well as related metabolites were measured. Using qPCR and NanoString technology, we profiled glial cell-associated gene expression changes. Finally, microglial morphology, astrocyte end feet, and microhemorrhages were analyzed using histological methods.ResultsAtorvastatin treatment of HHcy in mice led to no changes in total cholesterol but decreases in total homocysteine in plasma. While HHcy decreased expression of many glial genes, atorvastatin rescued these gene changes, which mostly occurred in oligodendrocytes and microglia. Microglia in HHcy mice with atorvastatin were trending towards fewer processes compared to control with atorvastatin, but there were no atorvastatin effects on astrocyte end feet. While atorvastatin treatment was trending towards increasing the area of microhemorrhages in HHcy mice in the frontal cortex, it only slightly (non-significantly) reduced the number of microhemorrhages. Finally, atorvastatin treatment in HHcy mice led to improved cognition on the novel object recognition task.ConclusionsThese data suggest that atorvastatin rescued cognitive changes induced by HHcy most likely through lowering plasma total homocysteine and rescuing gene expression changes rather than impacts on vascular integrity or microglial changes.

Potential inflammatory targets in the integrative health care of patients with sickle cell disease.

Inflammation plays an integral role in the complications of sickle cell disease (SCD), which can lead to vaso-occlusive crisis and extreme pain. SCD is accompanied by numerous complications, including cardiovascular disease, cognitive decline and endothelial dysfunction, contributing to mortality. As disease severity increases with age, the present study aimed to assess if age is also correlated with a definite pattern of progression of the two inflammatory markers, high-sensitivity C-reactive protein (hsCRP) and total homocysteine (tHCY). The findings of the present study could lead to an improved understanding of the threshold levels of these inflammatory markers and timely interventions to delay complications. In an observational study, levels of hsCRP and tHCY were analyzed in 70 patients (35 male and 35 female patients) with SCD aged between 5 and 16 years. hsCRP levels were in the high-risk range in 64.29% (n=45) of all male and female patients. A sex-wise distribution showed that, of the 35 male patients, 74.28% (n=26) were in the high-risk range, and of the 35 female patients, 54.28% (n=19) were in the high-risk range. An age-wise distribution showed that of the 41 patients in the 5-10-years age group, 70.73% (n=29), were in the high-risk range. In comparison, of the 29 patients in the 11-16-years age group, 55.17% (n=16) were in the high-risk range. tHCY levels were observed to be in the normal range in 98.57% (n=69) of all children, as compared with 1.43% (n=1) in the high-risk range. Furthermore, a sex-wise distribution showed that female patients in the high-risk group of hsCRP had higher concentrations of tHCY as compared with the male patients in that risk group. An age-wise distribution of hsCRP concentration also showed that the risk of CVD in patients in the 11-16-years age group was higher with increased concentrations of tHCY. A weak negative correlation was observed between age and hsCRP concentrations (r-value=-0.280; P=0.026) and a weak positive correlation was detected between tHCY and age (r-value=0.259; P=0.036). In conclusion, the results of the present study indicated that higher levels of hsCRP could be a useful marker in children with SCD, and levels of tHCY may be an adjunct marker as the disease progresses with age.

Hyperhomocysteinemia Increases Vascular Risk in Stroke Patients with Chronic Kidney Disease.

We aimed to assess the prognostic impact of hyperhomocysteinemia (HHcy) on the recurrent vascular event risk in stroke patients with or without chronic kidney disease (CKD). In this prospective observational study, 621 patients (mean age, 69.5 years; male, 62.2%) with ischemic stroke or transient ischemic attack were consecutively enrolled within 1 week of onset and followed-up for 1 year. HHcy was defined as elevated levels of fasting total homocysteine ＞15 µmol/L. CKD was defined as an estimated glomerular filtration rate of ＜60 mL/min/1.73 m2 or a history of renal replacement therapy. The primary outcome was a composite of major adverse cardiovascular events (MACEs), including nonfatal stroke, nonfatal acute coronary syndrome, major peripheral artery disease, and vascular death. The prevalence of HHcy was 18.5%. Patients with HHcy were more likely to have intracranial (37.4% versus 24.8%; p=0.008) and extracranial (20.9% versus 13.0%; p=0.037) artery stenosis than were those without HHcy. At 1 year, patients with HHcy were at a greater risk of MACE than were those without HHcy (annual rate, 17.8% versus 10.4%; log-rank p=0.033). In the Cox proportional hazard regression models, HHcy was independently associated with an increased risk of MACE in patients with CKD (adjusted hazard ratio [HR], 2.06; 95% confidence interval [CI], 1.02-4.20), whereas HHcy was not predictive of MACE in those without CKD (adjusted HR, 1.00; 95% CI, 0.30-3.32). Elevated levels of serum homocysteine can be an important modifiable risk factor in stroke patients with CKD, but not in those without CKD.

Would, early, versus late hydroxocobalamin dose intensification treatment, prevent cognitive decline, macular degeneration and ocular disease, in 5 patients with early-onset cblC deficiency?

In early-onset (EO) cblC deficiency (MMACHC), hydroxocobalamin dose-intensification (OHCBL-DI) improved biochemical and clinical outcome. In mammals, Cobalamin is reduced, in a reaction mediated by MMACHC. Pathogenic variants in MMACHC disrupt the synthesis pathway of methyl-cobalamin (MetCbl) and 5′-deoxy-adenosyl-cobalamin (AdoCbl), cofactors for both methionine synthase (MS) and methyl-malonyl-CoA mutase (MCM) enzymes. In 5 patients (pts.), with EO cblC deficiency, biochemical and clinical responses were studied following OHCbl-DI (mean ± SD 6,5 ± 3,3 mg/kg/day), given early, before age 5 months (pts. 1, 2, 3 and 4) or lately, at age 5 years (pt. 5). In all pts., total homocysteine (tHcy), methyl-malonic acid (MMA) and Cob(III)alamin levels were measured. Follow-up was performed during 74/12 years (pts. 1, 2, 3), 33/12 years (pt. 4) and 34/12 years (pt. 5). OHCbl was delivered intravenously or subcutaneously. Mean ± SD serum Cob(III)alamin levels were 42,2 × 106 ± 28, 0 × 106 pg/ml (normal: 200–900 pg/ml). In all pts., biomarkers were well controlled. All pts., except pt. 5, who had poor vision, had central vision, mild to moderate nystagmus, and with peri-foveolar irregularity in pts. 1, 2 and 4, yet none had the classic bulls' eye maculopathy and retinal degeneration characteristic of pts. with EO cblC deficiency. Only pt. 5, had severe cognitive deficiency. Both visual and cognitive functions were better preserved with early than with late OHCBL-DI. OHCBL-DI is suggested to bypass MMACHC, subsequently to be rescued by methionine synthase reductase (MSR) and adenosyl-transferase (ATR) to obtain Cob(I)alamin resulting in improved cognitive and retinal function in pts. with EO cblC deficiency.

Association of B vitamin intake and total homocysteine levels with all-cause and cause-specific mortality in central obesity

ObjectivesFuture primary prevention strategies may benefit from understanding the connection between mortality in individuals with central obesity and modifiable lifestyle factors like dietary intake. This study sought to determine whether there was a separate relationship between folate, vitamin B6, and vitamin B12 intake and all-cause and cause-specific mortality in the US population with central obesity. MethodsThe study analyzed data from the National Health and Nutrition Examination Survey between 1999 and 2016. Using the Cox proportional hazards model, the association between dietary intake of B vitamins and all-cause and cause-specific mortality was examined. A total of 7718 adults with central obesity were enrolled, with a mean age of 49.87 (SD = 0.25) y at baseline. ResultsFolate intake was independently associated with a decreased incidence of all-cause mortality (adjusted hazard ratio = 0.71; 95% CI, 0.58–0.87). Furthermore, higher intake of vitamin B6 and vitamin B12 was inversely correlated with cardiovascular disease mortality (adjusted hazard ratio = 0.63; 95% CI, 0.40–0.98; and adjusted hazard ratio = 0.44; 95% CI, 0.29–0.65, respectively) and the finding reveal an interaction between homocysteine and vitamin B12 and folate on All-cause mortality ConclusionsThe findings of this study suggest that vitamin B12 and folate intake may be protective factors in individuals with central obesity. It is important to consider both their total homocysteine level and body mass index in conjunction with these nutrients. Further research is needed to validate these findings.

Reference intervals for total serum homocysteine concentration in shenzhen adults investigated with the aid of nanomaterials

Hyperhomocysteinemia is a risk factor for cardiovascular disease. Therefore, assessing the reference intervals of total serum homocysteine concentration is a critical step in the process of preventing cardiovascular disease. The primary goals of this study were to evaluate gender- and age-related differences in homocysteine concentration in the general population of Shenzhen and possible influencing factors. This retrospective study enrolled 2665 healthy subjects aged 18 to 89 years (mean age, 46.68 years). Blood samples were collected and serum indexes were detected with the aid of magnetic nanoparticles, and serum homocysteine concentration was evaluated by the circulating enzymatic method. The reference intervals (5th and 95th percentiles) of total serum homocysteine concentrations were analyzed by the Hoffmann approach. This approach has been widely used to evaluate reference intervals for various analytical parameters. There were significant differences between males and females in some anthropometric and laboratory indexes in the Shenzhen general population. Men had higher levels of creatinine, uric acid, blood urea nitrogen, and homocysteine, whereas women had higher levels of estimated glomerular filtration rate and thyroid-stimulating hormone. Further studies showed that the reference intervals of total serum homocysteine showed significant differences between males and females and among subjects of different ages. These concentrations were higher in males (mean, 12.74 μmol/L) than in females, and the reference intervals increased with age. Men aged 18 to 40 years had a higher risk of hyperhomocysteinemia than women of the same age. Age- and gender-specific reference ranges of serum homocysteine were defined.

One-pot sample preparation procedure for the determination of protein N-linked homocysteine by HPLC-FLD based method

The report presents robust and high throughput method, based on liquid chromatography coupled with fluorescence detection (HPLC-FLD), for the determination of total protein N-linked homocysteine (Hcy) in human plasma. The assay involves simultaneous proteins precipitation with perchloric acid and removal of any other form of Hcy, except protein N-linked Hcy, via disulfides reduction with tris(2-carboxyethyl)phosphine (TCEP) and plasma protein pellet wash with perchloric acid followed by liberation of N-linked Hcy from proteins by hydrochloric acid hydrolysis, drying under vacuum and residue reconstitution in diluted hydrochloric acid. The chromatographic separation of resulting in this way Hcy-thiolactone (HTL) is achieved within 3 min at room temperature on PolymerX RP-1 (150 × 4.6 mm, 5.0 µm) column using isocratic elution with eluent, consisted of o-phthaldialdehyde (OPA) in sodium hydroxide and acetonitrile (ACN), delivered at a flow rate 1 mL/min. The analyte is quantified by monitoring fluorescence at 480 nm using excitation at 370 nm, in a linear range from 0.25 to 10 µmol/L in plasma, while the limit of quantification (LOQ) equals 0.25 µmol/L. The method was successfully applied to plasma samples delivered by fifteen apparently healthy donors showing that the HPLC-FLD assay is suitable for screening of human plasma.

Association between Plasma Homocysteine Level and Atherogenic Index of Plasma among Hypothyroid Patients - A Case-Control Study

Introduction: Hypothyroidism is a common metabolic disorder in general population. Hypothyroidism is a commonly encountered health problem in Bangladesh and morbidity and mortality toll due to cardiovascular disease resulting from hypothyroidism is quite high. Hypothyroidism, dyslipidaemia and hyperhomocysteinemia are recognized risk factor for atherosclerosis and cardiovascular disease. Aim of the Study: The aim of this study was to evaluate the association between plasma Homocysteine level and atherogenic Index of plasma in patients with hypothyroidism. Methods: This was a case-control study and conducted in the Department of Biochemistry in cooperation with Department of Endocrinology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh during the period from January, 2012 to December, 2013. In our study, we included 60 newly diagnosed hypothyroid individuals as case and 60 euthyroid individuals as control. Result: In this study, most of the participants were female (62%) compared to male (38%) and we found the mean age of the case and control group was 34.31 ± 11.77 years and 32.42 ± 12.51 years. Mean serum homocysteine was found significantly higher in case group (19.00 ± 7.58 µmol/L) than control group (9.59 ± 1.91µmol/L).Mean AIP was found significantly higher in case (0.75 ± 0.27) than control (0.35 ± 0.20). We found 49 (81.67%) cases were within increased risk group of atherogenesis where as in control group it was 28 (46.67%).In present study, mild hyperhomocysteinemia was found in 80% cases and moderate hyperhomocysteinemia in 13.3% cases where as in control group it was 10% &amp; 0% respectively. Conclusion: In this study, we found that total plasma homocysteine level was significantly increased in recently diagnosed hypothyroidism and was normal in control groups. We also found that hypothyroidism is associated with high atherogenic index and hyperhomocysteinemia which causes premature atherosclerosis.

Combined use of amlodipine and folic acid are significantly more efficacious than amlodipine alone in lowering plasma homocysteine and blood pressure among hypertensive patients with hyperhomocysteinemia and intolerance to ACEI: A multicenter, randomized, double-blind, parallel-controlled clinical trial.

Hyperhomocysteinemia with hypertension can synergistically increase the risk of stroke. The China stroke primary prevention trial showed that combining 0.8mg folic acid (FA) with angiotensin-converting enzyme inhibitor (ACEI) can effectively lower plasma total homocysteine (tHcy) and blood pressure (BP); and reduce first stroke risk by additional 21% compared to ACEI alone. However, intolerance to ACEI is common in Asians and amlodipine can be alternative. This is a multicenter, randomized, double-blind, parallel-controlled clinical trial (RCT) which evaluated whether amlodipine combined with FA is more efficacious than amlodipine alone in lowering tHcy and BP among Chinese hypertensive with hyperhomocysteinemia and intolerance to ACEI. 351 Eligible patients were randomly assigned by 1:1:1 ratio to receive amlodipine-FA tablet daily (amlodipine 5mg/FA 0.4mg, A group); amlodipine 5mg/FA 0.8mg tablet daily (B group); amlodipine 5mg daily (C group, control group). Follow-up was conducted at 2, 4, 6, and 8weeks. The primary outcome was efficacy of lowering both tHcy and BP at the end of 8-week treatment. Compared with C group, A group had a significantly higher rate of lowering both tHcy and BP (23.3%vs. 6.0%; Odds Ratio [OR], 8.68; 95% CI, 3.04-24.78, P<.001); B group also had a higher rate of lowering both tHcy and BP (20.3%vs. 6.0%; OR: 5.90; 95% CI, 2.11-16.47, P<.001). This RCT showed amlodipine combined with FA compared with amlodipine alone, each had significantly higher efficacy of lowering both tHcy and BP. No difference was found in BP-lowering and occurrence of adverse events between the three groups.

REVERSED PHASE HPLC DETERMINATION OF TOTAL HOMOCYSTEINE, CYSTEINE, CYSTEINYL GLYCINE, GLUTATHIONE IN PLASMA OF EPILEPTIC PATIENTS

The fast and accurate reversed-phase HPLC method was predicated on qualitative and quantitative estimation of the total concentrations of the essential thiols in the plasma of adults volunteers compared with epileptic patients, which is l-cysteine (Cys) total homocysteine (tHys), cysteinyl glycine (Cys-Gly), glutathione (GSH) and cysteamine (Cstm), respectively. The plasma samples of (50) epileptic patients were classified into three groups; the non-anti-epileptic drug consisted of 20 patients (12 male, eight female) who were mainly diagnosed with idiopathic generalized epilepsy. The mean age was 34 ± 13 (range 19–48) years. The second group consisted of 30 patients receiving two types of anti-epileptic drugs, 18 patients (12 male and six female) receiving Carbamazepine, and 12 patients (7 males and five female) receiving phenytoin. The mean age of the patients was 32 ± 11 Compared with 31 healthy volunteers (20 male and 11 female). The mean age of the controls was 31 ± 9 (range 26–49 years). The mean duration of treatment of patients receiving the anti-epileptic drug was six months). All measurement was done using pre-column derivatization with bromobimane, and the derivative of each standard mixture were baseline separated on C18-DB (50 x 4.6 mm ID) column, 3μm particle size. The regression coefficients for the separated and standard deviation SD within-run ranged from 0.09 to 8.40 μmol/L, and between-run ranged from 0.15to 9.16 μmol/L; the analytical procedure gave good linearity in the range between 1.25 to 20 µmole/ l, the detection limit was 0.1 µmole /L for all the thiol groups. Analytical recovery was 96.9–107.4 %; the mean concentration of plasma cysteine and total homocysteine was slightly higher in males than females; it was 221± 75 for adult males and 190± 44 μmol/L for adult females, while t-homocysteine was (10.55 ±2.45 vs. 9.79 ± 1.88 μmol/L, the results observed that the value of cysteine and homocysteine were significantly higher in epileptic patients using Carbamazepine and phenytoin than in healthy volunteers. Mean values for glutathione were lower, while cysteinyl glycine showed no significant difference in healthy and epileptic patients and no sex- and age-dependent.

Serum 5-Methyltetrahydrofolate Status Is Associated with One-Carbon Metabolism-Related Metabolite Concentrations and Enzyme Activity Indicators in Young Women.

Maintaining optimal one-carbon metabolism (OCM) is essential for health and pregnancy. In this cross-sectional study, folate status was assessed based on 5-methyltetrahydrofolate (5-MTHF) levels, and the association between 5-MTHF and OCM-related metabolites was investigated in 227 female Japanese university students aged 18-25 years. The participants were divided into high and low 5-MTHF groups based on their folate status. Serum samples of the participants were collected while they were fasting, and 18 OCM-related metabolites were measured using stable-isotope dilution liquid chromatography-electrospray tandem mass spectrometry. The association between serum 5-MTHF and OCM-related metabolite concentrations was assessed using Spearman's rank correlation coefficient. Serum 5-MTHF concentrations were negatively correlated with total homocysteine (tHcy) concentrations and positively correlated with S-adenosylmethionine (SAM) and total cysteine (tCys) concentrations. Serum 5-MTHF concentrations demonstrated a stronger negative correlation with tHcy/tCys than with tHcy alone. The negative correlation between betaine and tHcy concentrations was stronger in the low 5-MTHF group than in the high 5-MTHF group. The 5-MTHF status could be linked to Hcy flux into the transsulfuration pathway via SAM. Therefore, the tHcy/tCys ratio may be a more sensitive indicator of the 5-MTHF status than tHcy alone. Furthermore, a low 5-MTHF status can enhance Hcy metabolism via betaine.

Plasma thiol levels and methylenetetrahydrofolate reductase gene c.665C>T and c.1286A>C variants affect fibrin clot properties in Polish venous thromboembolic patients.

Aminothiols, including cysteine (Cys) and glutathione (GSH) in relation to fibrin clot phenotype were not investigated in patients with venous thromboembolism (VTE) and 5,10-methylenetetrahydrofolate reductase (MTHFR) gene variants. We aimed to explore the associations between MTHFR variants and plasma oxidative stress indicators including aminothiols as well as fibrin clot properties with plasma oxidative status and fibrin clot properties in this group of patients. In 387 VTE patients the MTHFR c.665C>T and c.1286A>C variants were genotyped, together with chromatographic separation of plasma thiols. We also determined nitrotyrosine levels and fibrin clot properties, including clot permeability (Ks), lysis time (CLT), and fibrin fibers thickness. There were 193 patients with MTHFR c.665C>T (49.9%) and 214 (55.3%) with c.1286A>C variants. Both allele carriers with total homocysteine (tHcy) levels >15μM (n=71, 18.3%), compared to patients with tHcy ≤15μM had 11.5% and 12.5% higher Cys levels, 20.6% and 34.3% higher GSH levels as well as 28.1% and 57.4% increased nitrotyrosine levels, respectively (all P<0.05). The MTHFR c.665C>T carriers with tHcy levels >15μM compared to tHcy ≤15μM had 39.4% reduced Ks and 9% reduced fibrin fibers thickness (both P<0.05) with no differences in CLT. In the MTHFR c.1286A>C carriers with tHcy levels >15μM, Ks was decreased by 44.5%, CLT prolonged by 46.1%, and fibrin fibers thickness was reduced by 14.5% compared to patients with tHcy ≤15μM (all P<0.05). Nitrotyrosine levels in MTHFR variants carriers correlated with Ks (r=-0.38, P<0.05) and fibrin fibers diameter (r=-0.50, P<0.05). Our study indicates that patients with MTHFR variants and tHcy >15μM are characterized by elevated Cys and nitrotyrosine levels associated with prothrombotic fibrin clot properties.

The Association Between Thymidylate Synthase Gene Polymorphisms and the Risk of Ischemic Stroke in Chinese Han Population

Family history of hypertension, smoking, diabetes and alcohol consumption and atherosclerotic plaque were identified as common risk factors in IS. We aimed at investigating the relationship between Thymidylate Synthase (TS) gene polymorphisms and ischemic stroke (IS).This case–control research selected and genotyped three single nucleotide polymorphisms (SNPs)of TS( rs699517, rs2790, and rs151264360) with Sanger sequencing in Chinese Han population. We also adopted logistic regression analysis in genetic models for calculating odds ratios and 95% confidence intervals. Genotype-Tissue Expression(GTEx) database analyzed the tissue-specific expression and TS polymorphisms. The ischemic stroke patients showed higher low-density lipoprotein cholesterol and total homocysteine (tHcy). It was found that patients with the TT genotype of rs699517 and GG genotype of rs2790 had larger degrees of tHcy than those with CC + CT genotypes and AA + AG genotypes, respectively. The genotype distribution of the three SNPs did not deviate from Hardy–Weinberg equilibrium (HWE). Haplotype analysis showed that T-G-del was the major haplotype in IS, and C-A-ins was the major haplotype in controls. GTEx database indicated that the rs699517 and rs2790 increased the expression of TS in healthy human and associated with TS expression level in a single tissue. In conclusion: This study has shown that TS rs699517 and rs2790 were significantly related to ischemic stroke patients.