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  1. Association of serum calcium concentrations with fibrinogen and homocysteine in nondiabetic Korean subjects

    PubMed Central

    Cho, Hyun Sun; Lee, Sung Won; Shin, Juyoung; Moon, Sung Dae; Han, Je Ho; Cha, Bong Yun; Kim, Eun Sook

    2016-01-01

    Abstract Considerable evidence shows that increased serum calcium levels are associated with metabolic disorders, cardiovascular disease, and increased mortality. This study investigated whether serum calcium, within a normal range, is significantly associated with serum fibrinogen and homocysteine, markers of increased cardiovascular disease risk in nondiabetic Korean subjects. A cross-sectional analysis was performed on 1096 subjects (mean age, 55.1 ± 11.1 years; 36.1% women) undergoing a general health checkup. Serum biochemistry was analyzed including serum albumin-corrected calcium (Cac), insulin resistance (IR, using homeostasis model assessment [HOMA]), fibrinogen, and homocysteine. Compared with patients within the lowest Cac quartile, those with higher Cac levels had increased fibrinogen and homocysteine levels as well as an increased proportion of smoking, dyslipidemia, and HOMA-IR. Correlation analyses revealed linear relationships for Cac with fibrinogen and homocysteine in both genders. After adjustment for confounding factors, serum Cac was significantly associated with high fibrinogen (odds ratio [OR] for the highest vs the lowest quartile = 1.76, 95% confidence interval [CI] = 1.09–2.83, P = 0.02) and homocysteine (OR = 1.83, 95% CI = 1.07–3.11, P = 0.027). Multivariate regression models showed that Cac was linearly associated with fibrinogen (standardized β = 0.14, P < 0.001) and homocysteine (standardized β = 0.07, P = 0.009). High normal calcium concentrations were independently associated with increased levels of fibrinogen and homocysteine. Further investigation is needed to validate whether slightly increased calcium levels within the normal range indicate a higher risk of cardiovascular disease. PMID:27310988

  2. Homocysteine levels in vegetarians versus omnivores.

    PubMed

    Krajcovicová-Kudlácková, M; Blazícek, P; Kopcová, J; Béderová, A; Babinská, K

    2000-01-01

    Vitamin B(12), folate, and vitamin B(6) are the main determinants of homocysteinemia. The vegan diet provides no vitamin B(12), but also less strict forms of alternative nutrition may suffer from a deficit of this vitamin. The plasma homocysteine level was measured in alternative nutrition groups of adults (lacto- and lactoovovegetarians, n = 62; vegans, n = 32) and compared with the levels in a group consuming traditional diet (n = 59), omnivores). In the group of vegetarians the average homocysteine level is 13.18 vs. 10.19 micromol/l in omnivores; the frequency of hyperhomocysteinemia is 29 vs. 5% in omnivores. In the group of vegans the average homocysteine value is 15.79 micromol/l (53% of the individual values exceeded 15 micromol/l). Omnivores consume the recommended amount of methionine; however, in individuals consuming an alternative diet, the intake of methionine is deficient (assessed by food frequency questionnaire; lower content of methionine in plant proteins). Under conditions of lower methionine availability the remethylation pathway prevails; therefore, vitamin B(12) and folate were evaluated in relation to the homocysteine level. The serum vitamin B(12) levels are significantly lower in the alternative nutrition groups (214.8 pmol/l in vegetarians, 140.1 pmol/l in vegans vs. 344.7 pmol/l in omnivores); a deficit (<179.0 pmol/l) was found in 26% of the vegetarians and in 78% of the vegans vs. 0% in omnivores. The serum folate levels were within the range of reference values in all groups; however, they were significantly lower in omnivores. The results show that the mild hyperhomocysteinemia in alternative nutrition is a consequence of vitamin B(12) deficiency.

  3. [Gastrointestinal disease with elevated plasma homocysteine level].

    PubMed

    Coll, P; Guttormsen, A B; Berstad, A

    1999-10-10

    Elevated plasma homocystein (tHcy) is a marker for functional deficiency of folate and/or cobalamin. Malabsorption of these vitamins occurs in various gastroenterologic diseases. A frequent mutation (C677T) in the gene coding for the enzyme methyltetrahydrofolate reductase (MTHFR) is often associated with elevated values of tHcy. We have investigated 24 patients with tHcy > 40 mumol/l for gastrointestinal disease that can contribute to such elevation. Of these, 19 were homozygous for mutated MTHFR, four were heterozygous and one was normal. We found two cases of probable celiac disease, one case of Crohn's disease and one case of ulcerative colitis. These four were homozygous for the C667T mutation. Furthermore, we found eight persons who were anacidic; four homozygous, three heterozygous and one normal. All had gastritis histologically, six had serum gastrin > 50 pmol/l, and four were already on treatment with cobalamin injections. Helicobacter pylori-infection was found in nine out of 22 persons. Gastrointestinal disease occurs frequently in patients with tHcy > 40 mumol/l, but with the exception of conditions resulting in serious deficiency of cobalamin, these diseases alone do not seem sufficient to cause such high levels. We suggest that a reasonable approach to patients with homocystein values above 40 mumol/l is to exclude cobalamin deficiency, and that further investigations should be based upon thorough anamnesis and symptoms. PMID:10563175

  4. [Plasma homocysteine levels in patients with ischemic heart disease].

    PubMed

    Márk, L; Erdei, F; Márki-Zay, J; Nagy, E; Kondacs, A; Katona, A

    2001-07-29

    In the latest years it became clear that beside traditional cardiovascular risk factors the high plasma homocysteine level increases the risk of atherosclerotic diseases too. Metaanalysis of 27 papers found that 10% of population's coronary risk is attributable to homocysteine and a 5 mumol/l increase in its plasma level elevates the coronary risk by as much as 0.5 mumol/l cholesterol increase. Recent studies have shown an inverse relation between the levels of plasma homocysteine and that of folic acid, vitamin B6, vitamin B12. The latters are cofactors and substrates of the homocysteine and methionin metabolism. The plasma total cholesterol, HDL-cholesterol, triglyceride, lipoprotein(a), Apo A1, Apo B and homocysteine concentrations were examined in 39 patients suffering from coronary artery disease treated in the Cardiac Rehabilitation Department of our hospital. Twenty of them were treated by folic acid and vitamin B6 for a three week period. The mean (+/- SD) plasma homocysteine concentration was 15.60 +/- 6.14 mumol/l. In the treated subgroup the mean (+/- SD) plasma homocysteine concentration was 17.3 +/- 7.00 mumol/l, the mean (+/- SD) plasma folic acid level was 8.58 +/- 4.6 mumol/l. After the three week treatment period (folic acid and vitamin B6) the plasma homocysteine level decreased by 26.5% (p = 0.012), that of folic acid increased by 68.7% (p = 0.002). From the plasma lipids the level of total- and LDL-cholesterol decreased significantly (6.7% and 10.4%, P < 0.05), caused by the strict diet during hospital treatment. As for the genetic polymorphism of the V677 gen of the metylenetetrahydrofolate-reductase (MTHFR) enzyme there was a significant correlation with homocysteine level (r = 0.436, p = 0.010), and a negative, but not significant correlation with the folic acid level (r = -0.354).

  5. Genetic variation in the fibrinogen gamma gene increases the risk for deep venous thrombosis by reducing plasma fibrinogen gamma' levels.

    PubMed

    Uitte de Willige, Shirley; de Visser, Marieke C H; Houwing-Duistermaat, Jeanine J; Rosendaal, Frits R; Vos, Hans L; Bertina, Rogier M

    2005-12-15

    We investigated the association between haplotypes of fibrinogen alpha (FGA), beta (FGB), and gamma (FGG), total fibrinogen levels, fibrinogen gamma' (gammaA/gamma' plus gamma'/gamma') levels, and risk for deep venous thrombosis. In a population-based case-control study, the Leiden Thrombophilia Study, we typed 15 haplotype-tagging single nucleotide polymorphisms (htSNPs) in this gene cluster. None of these haplotypes was associated with total fibrinogen levels. In each gene, one haplotype increased the thrombosis risk approximately 2-fold. After adjustment for linkage disequilibrium between the genes, only FGG-H2 homozygosity remained associated with risk (odds ratio [OR], 2.4; 95% confidence interval [95% CI], 1.5-3.9). FGG-H2 was also associated with reduced fibrinogen gamma' levels and reduced ratios of fibrinogen gamma' to total fibrinogen. Multivariate analysis showed that reduced fibrinogen gamma' levels and elevated total fibrinogen levels were both associated with an increased risk for thrombosis, even after adjustment for FGG-H2. A reduced fibrinogen gamma' to total fibrinogen ratio (less than 0.69) also increased the risk (OR, 2.4; 95% CI, 1.7-3.5). We propose that FGG-H2 influences thrombosis risk through htSNP 10034C/T [rs2066865] by strengthening the consensus of a CstF site and thus favoring the formation of gammaA chain above that of gamma' chain. Fibrinogen gamma' contains a unique high-affinity, nonsubstrate binding site for thrombin, which seems critical for the expression of the antithrombin activity that develops during fibrin formation (antithrombin 1).

  6. Daily rhythms in plasma levels of homocysteine

    PubMed Central

    Lavie, Lena; Lavie, Peretz

    2004-01-01

    Background There is accumulated evidence that plasma concentration of the sulfur-containing amino-acid homocysteine (Hcy) is a prognostic marker for cardiovascular morbidity and mortality. Both fasting levels of Hcy and post methionine loading levels are used as prognostic markers. The aim of the present study was to investigate the existence of a daily rhythm in plasma Hcy under strictly controlled nutritional and sleep-wake conditions. We also investigated if the time during which methionine loading is performed, i.e., morning or evening, had a different effect on the resultant plasma Hcy concentration. Methods Six healthy men aged 23–26 years participated in 4 experiments. In the first and second experiments, the daily rhythm in Hcy as well as in other amino acids was investigated under a normal or an inverse sleep-wake cycle. In the third and fourth, Hcy concentrations were investigated after a morning and evening methionine loading. To standardize food consumption in the first two experiments, subjects received every 3 hours 150 ml of specially designed low-protein liquid food (Ensure® formula). Results In both the first and second experiments there was a significant daily rhythm in Hcy concentrations with a mid-day nadir and a nocturnal peak. Strikingly different 24-h patterns were observed in methionine, leucine, isoleucine and tyrosine. In all, the 24-h curves revealed a strong influence of both the sleep-wake cycle and the feeding schedule. Methionine loading resulted in increased plasma Hcy levels during both morning and evening experiments, which were not significantly different from each other. Conclusions There is a daily rhythm in plasma concentration of the amino acid Hcy, and this rhythm is independent of sleep-wake and food consumption. In view of the fact that increased Hcy concentrations may be associated with increased cardiovascular risks, these findings may have clinical implications for the health of rotating shift workers. PMID:15347422

  7. Increased plasma homocysteine levels in shift working bus drivers

    PubMed Central

    Martins, P; D'Almeida, V; Vergani, N; Perez, A; Tufik, S

    2003-01-01

    Background: Previous studies have indicated an association between shift work and cardiovascular disease. There is also considerable epidemiological evidence that hyperhomocysteinemia is an independent risk factor for cardiovascular disorders. Aims: To analyse plasma homocysteine levels in shift work bus drivers, and to investigate possible relations with sleep parameters and other biochemical factors. Methods: Blood samples were collected from 30 male shift working long-haul bus drivers in a Brazilian sample and analysed for plasma levels of homocysteine, folic acid, vitamin B12, and serum lipids. A group of 22 daytime workers, matched for age and body mass index served as controls. The incidence of mutations in the gene coding for methylene tetrahydrofolate, an enzyme which is related to hyperhomocysteinemia, was also assessed. Polysomnographic recordings were obtained from the target group. Results: Bus drivers showed significantly higher levels of plasma homocysteine than the control group (18.57 v 9.43 µM). Most of the other biochemical, behavioural, and molecular parameters did not differ between groups. Likewise, sleep parameters appeared to be within the normal range. Conclusions: The significantly increased plasma homocysteine levels in long-haul bus drivers did not appear to be secondary to other biochemical or behavioural problems in this group. These results suggest that hyperhomocysteinemia may be involved in the increased incidence of cardiovascular diseases observed in shift workers. PMID:12937187

  8. Serum homocysteine level in vegetarians in District Tharparker, Sindh

    PubMed Central

    Kapoor, Aneel; Zuberi, Nudrat Anwar; Rathore, M. Imran; Baig, Mukhtiar

    2015-01-01

    Objectives: The aim of present study was to investigate serum homocysteine levels in apparently healthy vegetarians and ominvores in Mithi, district Tharparker, Sindh, Pakistan. Methods: This study was conducted in the Department of Biochemistry, Basic Medical Sciences Institute (BMSI), Jinnah Postgraduate Medical Center (JPMC), Karachi and blood samples were collected from Mithi, district Tharparker, Sindh, Pakistan, in 2012. One hundred vegetarian and one hundred omnivores (age ranging from 20-40 years) were enrolled for this study. Serum homocysteine levels were measured by the chemiluminescence enzyme immunoassay method. Results: Serum homocysteine (Hcy) level was considerably higher (p<0.001) in vegetarian group compared to omnivores. We further grouped and analyzed our study subjects according to their gender and according to Hcy level (greater than or lower than 15µmol/L). A considerable number of vegetarian subjects 30% were having Hcy >15µmol/L compared to omnivores 6%, (p<0.001). Gender-wise comparison showed that 27.02% male and 38.46% females had >15µmol/L serum Hcy level in vegetarian group and 6.9% male and 3.5% females had >15µmol/L serum Hcy level in omnivores group, but the difference was not significant in any group. Conclusion: Vegetarians are more prone to develop hyperhomocysteinemia, so they are at high risk to develop cardiovascular disease. PMID:25878628

  9. High-level expression and preparation of recombinant human fibrinogen as biopharmaceuticals.

    PubMed

    Hirashima, Masaki; Imamura, Takayuki; Yano, Kentaro; Kawamura, Ryoichi; Meta, Akihiro; Tokieda, Yoshiyuki; Nakashima, Toshihiro

    2016-02-01

    Fibrinogen is a large and complex glycoprotein containing two sets of each of three different chains (α, β and γ). There have been no reports of high-level expression of fibrinogen at commercial levels using mammalian cultured cells such as CHO cells because of the difficulty in highly expressing a protein with such a complex structure. We achieved high-level (1.3 g/l or higher) expression of recombinant human fibrinogen using CHO DG44 cells by optimizing the expression system and culture conditions. We also succeeded in establishing a high-recovery preparation method for recombinant fibrinogen that rarely yields degraded products. To characterize the properties of the recombinant human fibrinogen, we performed SDS-PAGE; western blotting of the α, β and γ chains using specific antibodies and scanning electron microscopy observations of fibrin fibres. We also evaluated the functional equivalence between recombinant fibrinogen and plasma fibrinogen with respect to the release of fibrinopeptides initiated by thrombin and its cross-linking properties. The basic properties of recombinant fibrinogen showed no apparent differences from those of plasma fibrinogen. Here, we report the development of methods for the culture and preparation of recombinant human fibrinogen of satisfactory quality that can be scaled up to the commercial level.

  10. Genetic Influences on Plasma Homocysteine Levels in African Americans and Yoruba Nigerians.

    PubMed

    Kim, Sungeun; Nho, Kwangsik; Ramanan, Vijay K; Lai, Dongbing; Foroud, Tatiana M; Lane, Katie; Murrell, Jill R; Gao, Sujuan; Hall, Kathleen S; Unverzagt, Frederick W; Baiyewu, Olusegun; Ogunniyi, Adesola; Gureje, Oye; Kling, Mitchel A; Doraiswamy, P Murali; Kaddurah-Daouk, Rima; Hendrie, Hugh C; Saykin, Andrew J

    2015-01-01

    Plasma homocysteine, a metabolite involved in key cellular methylation processes seems to be implicated in cognitive functions and cardiovascular health with its high levels representing a potential modifiable risk factor for Alzheimer's disease (AD) and other dementias. A better understanding of the genetic factors regulating homocysteine levels, particularly in non-white populations, may help in risk stratification analyses of existing clinical trials and may point to novel targets for homocysteine-lowering therapy. To identify genetic influences on plasma homocysteine levels in individuals with African ancestry, we performed a targeted gene and pathway-based analysis using a priori biological information and then to identify new association performed a genome-wide association study. All analyses used combined data from the African American and Yoruba cohorts from the Indianapolis-Ibadan Dementia Project. Targeted analyses demonstrated significant associations of homocysteine and variants within the CBS (Cystathionine beta-Synthase) gene. We identified a novel genome-wide significant association of the AD risk gene CD2AP (CD2-associated protein) with plasma homocysteine levels in both cohorts. Minor allele (T) carriers of identified CD2AP variant (rs6940729) exhibited decreased homocysteine level. Pathway enrichment analysis identified several interesting pathways including the GABA receptor activation pathway. This is noteworthy given the known antagonistic effect of homocysteine on GABA receptors. These findings identify several new targets warranting further investigation in relation to the role of homocysteine in neurodegeneration.

  11. Homocysteine Serum Levels in Diabetic Patients with Non Proliferative, Proliferative and without Retinopathy

    PubMed Central

    Gagliano, Caterina; Giordano, Maria; Vacante, Marco; Caraci, Filippo; Drago, Filippo; Avitabile, Teresio; Motta, Massimo

    2014-01-01

    Homocysteine has been associated with extracellular matrix changes. The diabetic retinopathy is a neurovascular complication of diabetes mellitus and it is the leading cause of vision loss among working adults worldwide. In this study, we evaluate the role of homocysteine in diabetic retinopathy analyzing the plasma levels of homocysteine in 63 diabetic type 2 patients with nonproliferative retinopathy (NPDR), 62 patients with proliferative diabetic retinopathy (PDR), 50 healthy subjects used as control group, and 75 randomly selected patients. PMID:24877066

  12. Homocysteine serum levels in diabetic patients with non proliferative, proliferative and without retinopathy.

    PubMed

    Malaguarnera, Giulia; Gagliano, Caterina; Giordano, Maria; Salomone, Salvatore; Vacante, Marco; Bucolo, Claudio; Caraci, Filippo; Reibaldi, Michele; Drago, Filippo; Avitabile, Teresio; Motta, Massimo

    2014-01-01

    Homocysteine has been associated with extracellular matrix changes. The diabetic retinopathy is a neurovascular complication of diabetes mellitus and it is the leading cause of vision loss among working adults worldwide. In this study, we evaluate the role of homocysteine in diabetic retinopathy analyzing the plasma levels of homocysteine in 63 diabetic type 2 patients with nonproliferative retinopathy (NPDR), 62 patients with proliferative diabetic retinopathy (PDR), 50 healthy subjects used as control group, and 75 randomly selected patients. PMID:24877066

  13. Serum homocysteine level in patients with ankylosing spondylitis.

    PubMed

    Başkan, Bedriye Mermerci; Sivas, Filiz; Aktekin, Lale Akbulut; Doğan, Yasemin Pekin; Ozoran, Kürşat; Bodur, Hatice

    2009-10-01

    In this study serum homocystein (Hcy) level was measured and its relationship with disease activity criteria and treatment protocols was investigated in ankylosing spondylitis (AS) patients. Ninety-two AS patients and 58 healthy individuals were recruited. Erythrocyte sedimentation rate and serum C-reactive protein were determined. Bath AS disease activity index and Bath AS functional index were calculated. Serum Hcy levels >15 micromol/l were considered as hyperhomocysteinemia. The mean serum homocysteine levels were 14.40 and 12.60 micromol/l in patients with AS and the control group, respectively, and the difference between two groups was significant. While there was no significant difference between the sulfasalazine (SSZ) group with 14.25 micromol/l mean Hcy level and the methotrexate (MTX)/SSZ group with 16.05 micromol/l, there was a statistically significant difference between the Hcy levels of these two groups and Hcy level of 12.15 micromol/l of the non-steroidal anti-inflammatory drugs group, and 12.60 micromol/l Hcy level of the control group. Mean serum Hcy level was 13.65 micromol/l in patients with active AS and 14.60 micromol/l in patients with inactive AS, and there was no significant difference between the groups. In our study serum Hcy level was found to be significantly higher in patients with AS than in healthy control subjects. Especially for the AS patients receiving MTX and SSZ treatment without folic acid supplementation, addition of folic acid to their therapy may decrease the risk of cardiovascular disease which in turn decreases the mortality in these patients, but further prospective studies are needed for supporting these results. PMID:19288264

  14. Identification of gene-gene and gene-environment interactions within the fibrinogen gene cluster for fibrinogen levels in three ethnically diverse populations.

    PubMed

    Jeff, Janina M; Brown-Gentry, Kristin; Crawford, Dana C

    2015-01-01

    Elevated levels of plasma fibrinogen are associated with clot formation in the absence of inflammation or injury and is a biomarker for arterial clotting, the leading cause of cardiovascular disease. Fibrinogen levels are heritable with >50% attributed to genetic factors, however little is known about possible genetic modifiers that might explain the missing heritability. The fibrinogen gene cluster is comprised of three genes (FGA, FGB, and FGG) that make up the fibrinogen polypeptide essential for fibrinogen production in the blood. Given the known interaction with these genes, we tested 25 variants in the fibrinogen gene cluster for gene x gene and gene x environment interactions in 620 non-Hispanic blacks, 1,385 non-Hispanic whites, and 664 Mexican Americans from a cross-sectional dataset enriched with environmental data, the Third National Health and Nutrition Examination Survey (NHANES III). Using a multiplicative approach, we added cross product terms (gene x gene or gene x environment) to a linear regression model and declared significance at p < 0.05. We identified 19 unique gene x gene and 13 unique gene x environment interactions that impact fibrinogen levels in at least one population at p < 0.05. Over 90% of the gene x gene interactions identified include a variant in the rate-limiting gene, FGB that is essential for the formation of the fibrinogen polypeptide. We also detected gene x environment interactions with fibrinogen variants and sex, smoking, and body mass index. These findings highlight the potential for the discovery of genetic modifiers for complex phenotypes in multiple populations and give a better understanding of the interaction between genes and/or the environment for fibrinogen levels. The need for more powerful and robust methods to identify genetic modifiers is still warranted. PMID:25592583

  15. IDENTIFICATION OF GENE-GENE AND GENE-ENVIRONMENT INTERACTIONS WITHIN THE FIBRINOGEN GENE CLUSTER FOR FIBRINOGEN LEVELS IN THREE ETHNICALLY DIVERSE POPULATIONS

    PubMed Central

    Jeff, Janina M.; Brown-Gentry, Kristin; Crawford, Dana C.

    2014-01-01

    Elevated levels of plasma fibrinogen are associated with clot formation in the absence of inflammation or injury and is a biomarker for arterial clotting, the leading cause of cardiovascular disease. Fibrinogen levels are heritable with >50% attributed to genetic factors, however little is known about possible genetic modifiers that might explain the missing heritability. The fibrinogen gene cluster is comprised of three genes (FGA, FGB, and FGG) that make up the fibrinogen polypeptide essential for fibrinogen production in the blood. Given the known interaction with these genes, we tested 25 variants in the fibrinogen gene cluster for gene × gene and gene × environment interactions in 620 non-Hispanic blacks, 1,385 non-Hispanic whites, and 664 Mexican Americans from a cross-sectional dataset enriched with environmental data, the Third National Health and Nutrition Examination Survey (NHANES III). Using a multiplicative approach, we added cross product terms (gene × gene or gene × environment) to a linear regression model and declared significance at p < 0.05. We identified 19 unique gene × gene and 13 unique gene × environment interactions that impact fibrinogen levels in at least one population at p <0.05. Over 90% of the gene × gene interactions identified include a variant in the rate-limiting gene, FGB that is essential for the formation of the fibrinogen polypeptide. We also detected gene × environment interactions with fibrinogen variants and sex, smoking, and body mass index. These findings highlight the potential for the discovery of genetic modifiers for complex phenotypes in multiple populations and give a better understanding of the interaction between genes and/or the environment for fibrinogen levels. The need for more powerful and robust methods to identify genetic modifiers is still warranted. PMID:25592583

  16. Identification of gene-gene and gene-environment interactions within the fibrinogen gene cluster for fibrinogen levels in three ethnically diverse populations.

    PubMed

    Jeff, Janina M; Brown-Gentry, Kristin; Crawford, Dana C

    2015-01-01

    Elevated levels of plasma fibrinogen are associated with clot formation in the absence of inflammation or injury and is a biomarker for arterial clotting, the leading cause of cardiovascular disease. Fibrinogen levels are heritable with >50% attributed to genetic factors, however little is known about possible genetic modifiers that might explain the missing heritability. The fibrinogen gene cluster is comprised of three genes (FGA, FGB, and FGG) that make up the fibrinogen polypeptide essential for fibrinogen production in the blood. Given the known interaction with these genes, we tested 25 variants in the fibrinogen gene cluster for gene x gene and gene x environment interactions in 620 non-Hispanic blacks, 1,385 non-Hispanic whites, and 664 Mexican Americans from a cross-sectional dataset enriched with environmental data, the Third National Health and Nutrition Examination Survey (NHANES III). Using a multiplicative approach, we added cross product terms (gene x gene or gene x environment) to a linear regression model and declared significance at p < 0.05. We identified 19 unique gene x gene and 13 unique gene x environment interactions that impact fibrinogen levels in at least one population at p < 0.05. Over 90% of the gene x gene interactions identified include a variant in the rate-limiting gene, FGB that is essential for the formation of the fibrinogen polypeptide. We also detected gene x environment interactions with fibrinogen variants and sex, smoking, and body mass index. These findings highlight the potential for the discovery of genetic modifiers for complex phenotypes in multiple populations and give a better understanding of the interaction between genes and/or the environment for fibrinogen levels. The need for more powerful and robust methods to identify genetic modifiers is still warranted.

  17. The relationship between plasma homocysteine level and different treatment modalities in patients with ankylosing spondylitis.

    PubMed

    Capkin, Erhan; Karkucak, Murat; Akyüz, Ayşe; Alver, Ahmet; Turkyilmaz, Aysegul Kucukali; Zengin, Elif

    2012-08-01

    To determine plasma homocysteine levels in ankylosing spondylitis (AS) and their correlation with disease activity measurements. To examine the effects of different treatment modalities on homocysteine levels. One hundred eight patients diagnosed with AS according to New York criteria and 65 healthy individuals matched in terms of age and gender were enrolled in the study. Patients were given detailed physical examinations. The Bath AS Disease Activity Index (BASDAI) was used for disease activity, the Bath AS Metrology Index (BASMI) for spinal mobility, the Bath AS Functional Index (BASFI) to determine functional status and the Bath AS Radiological Index (BASRI) for radiological analysis. Sedimentation rate (ESR) and C reactive protein (CRP) levels, acute phase reactants, were measured. Plasma homocysteine levels, serum interleukin (IL) -6 and serum tumor necrosis factor- α (TNF- α) levels were investigated using the enzyme-linked immunosorbent assay (ELISA) method. Plasma homocysteine levels in AS patients were statistically significantly lower compared with those in the healthy control group (P = 0.0001). There was no significant difference among sub-groups established on the basis of medical treatments and disease activity (BASDAI ≤4 and >4). No statistically significant correlation was determined between homocysteine level and disease activity parameters, radiological score and functional indices. A significant negative correlation was, however, established between age and homocysteine level in the AS group (P < 0.05, r = -0.426). Plasma homocysteine was lower in AS patients compared with the control group. This is not correlated with disease activation and medical treatment employed.

  18. Higher Fibrinogen Levels Predict Progression of Coronary Artery Calcification in Adults with Type 1 Diabetes

    PubMed Central

    Rodrigues, T.C.; Snell-Bergeon, J.K.; Maahs, D.M; Kinney, G.L.; Rewers, M.

    2010-01-01

    Aim To determine whether fibrinogen levels predict independently progression of coronary artery calcification (CAC) in adults with type 1 diabetes. Methods Data from a prospective cohort - the Coronary Artery Calcification in Type 1 Diabetes Study - were evaluated. Fibrinogen levels at baseline were separated into quartiles. CAC was measured twice and averaged at baseline and at follow-up 2.4 ± 0.4 years later. CAC progressors were defined as participants whose square-root transformed CAC volume increased by ≥ 2.53 or development mm of clinical coronary artery disease during the follow-up period. Results Fibrinogen levels were higher in progressors than in non-progressors (276 ± 61 mg/dl versus 259 ± 61 mg/dl, p = 0.0003). CAC progression, adjusted for known cardiovascular risk factors, increased in the highest quartile. Conclusions Higher fibrinogen levels predict CAC progression in type 1 diabetes subjects, independent of standard cardiovascular risk factors. PMID:20079495

  19. Homocysteine Levels in Parkinson's Disease: Is Entacapone Effective?

    PubMed

    Kocer, Bilge; Guven, Hayat; Comoglu, Selim Selcuk

    2016-01-01

    Plasma homocysteine (Hcy) levels may increase in levodopa-treated patients with Parkinson's disease (PD) as a consequence of levodopa methylation via catechol-O-methyltransferase (COMT). Results from previous studies that assessed the effect of COMT inhibitors on levodopa-induced hyperhomocysteinemia are conflicting. We aimed to evaluate the effects of levodopa and entacapone on plasma Hcy levels. A hundred PD patients were enrolled to the study and divided into three treatment groups (group I: levodopa and/or dopamine agonists; group II: levodopa, entacapone, and/or a dopamine agonist; and group III: dopamine agonist alone). We measured the serum B12, folic acid, and Hcy levels in all patients. There were no statistically significant differences between groups in terms of modified Hoehn and Yahr stages, Unified Parkinson's Disease Rating Scale II/III, Standardized Mini-Mental Test scores, and serum vitamin B12 and folic acid levels. Plasma median Hcy levels were found above the normal laboratory values in groups I and II, but they were normal in group III. However, there was no statistically significant difference in plasma Hcy levels between groups. Our results showed that levodopa treatment may cause a slight increase in the Hcy levels in PD compared with dopamine agonists and that COMT inhibitors may not have a significant effect on preventing hyperhomocysteinemia. PMID:27493964

  20. Sex Difference in the Association between Serum Homocysteine Level and Non-Alcoholic Fatty Liver Disease

    PubMed Central

    Won, Bo-Youn; Lee, Soo-Hyun; Yun, Sung-Hwan; Kim, Moon-Jong; Park, Kye-Seon; Kim, Young-Sang; Haam, Ji-Hee; Kim, Hyung-Yuk; Kim, Hye-Jung; Park, Ki-Hyun

    2016-01-01

    Background The relationship between serum homocysteine levels and non-alcoholic fatty liver disease is poorly understood. This study aims to investigate the sex-specific relationship between serum homocysteine level and non-alcoholic fatty liver disease in the Korean population. Methods This cross-sectional study included 150 men and 132 women who participated in medical examination programs in Korea from January 2014 to December 2014. Patients were screened for fatty liver by abdominal ultrasound and patient blood samples were collected to measure homocysteine levels. Patients that consumed more than 20 grams of alcohol per day were excluded from this study. Results The homocysteine level (11.56 vs. 8.05 nmol/L) and the proportion of non-alcoholic fatty liver disease (60.7% vs. 19.7%) were significantly higher in men than in women. In men, elevated serum homocysteine levels were associated with a greater prevalence of non-alcoholic fatty liver disease (quartile 1, 43.6%; quartile 4, 80.6%; P=0.01); however, in females, there was no significant association between serum homocysteine levels and the prevalence of non-alcoholic fatty liver disease. In the logistic regression model adjusted for age and potential confounding parameters, the odds ratio for men was significantly higher in the uppermost quartile (model 3, quartile 4: odds ratio, 6.78; 95% confidential interval, 1.67 to 27.56); however, serum homocysteine levels in women were not associated with non-alcoholic fatty liver disease in the crude model or in models adjusted for confounders. Conclusion Serum homocysteine levels were associated with the prevalence of non-alcoholic fatty liver disease in men. PMID:27468343

  1. Plasma homocysteine levels in Taiwanese vegetarians are higher than those of omnivores.

    PubMed

    Hung, Chien-Jung; Huang, Po-Chao; Lu, Shao-Chun; Li, Yi-Hwei; Huang, Hsien-Bin; Lin, Bi-Fong; Chang, Sue-Joan; Chou, Hsu-Fang

    2002-02-01

    Mild hyperhomocysteinemia is an independent risk factor for cardiovascular disease and may result from a deficiency of folate, vitamin B-6 or vitamin B-12. Because vitamin B-12 deficiency is often associated with vegetarianism, this study was designed to examine the effect of Taiwanese vegetarian diets on B-vitamin status and plasma homocysteine levels. Female Buddhist lacto-vegetarians (n = 45; 31-45 y) and matched omnivores (n = 45) recruited in Hualien, Taiwan, were investigated. Taiwanese vegetarians consumed normal amount of folate, but only 21% of Taiwan Recommended Daily Nutrient Allowances (RDNA) values of vitamin B-12. Compared with the omnivores, the vegetarians had significantly higher levels of plasma folate (14.79 +/- 7.70 vs. 11.98 +/- 8.29 nmol/L), but lower levels of vitamin B-12 (207.7 +/- 127.1 vs. 403.5 +/- 138.9 pmol/L). Fasting plasma homocysteine levels were significantly higher in vegetarians than in omnivores (mean: 11.20 +/- 4.27 vs. 8.64 +/- 2.06 micromol/L; median: 10.5 vs. 8.5 micromol/L). Fasting plasma homocysteine was inversely correlated with plasma folate and vitamin B-12 in the vegetarian group. Multiple regression analysis revealed that plasma folate, vitamin B-12 and creatinine were independent determinants of homocysteine variation and contributed to 38.6% of homocysteine variation in the vegetarians. Compared with the omnivores, vegetarians also had significantly lower serum levels of valine, isoleucine, leucine, lysine, alanine and arginine, but higher levels of glycine. In the vegetarian group, fasting plasma homocysteine correlated negatively with serum threonine, lysine, histidine, arginine and cystine, and these amino acids contributed to 38.7% of homocysteine variation. In conclusion, the Buddhist nuns who consumed a lacto-vegetarian diet had mildly elevated fasting plasma homocysteine levels presumably due to lower levels of plasma vitamin B-12.

  2. Vitamin supplementation reduces the level of homocysteine in the urine of autistic children.

    PubMed

    Kałużna-Czaplińska, Joanna; Michalska, Monika; Rynkowski, Jacek

    2011-04-01

    Significant differences in homocysteine levels in the urine of autistic children are observed. We hypothesized that vitamin supplementation might reduce the level of urinary homocysteine. To rationalize such a hypothesis, analyses were performed using the gas chromatography/mass spectrometry method. The homocysteine level in the urine of autistic children was measured twice: (1) before vitamin supplementation (group C, 30 autistic children) and (2) after supplementation, with either folic acid and vitamins B(6) and B(12) (group A1, 24 autistic children) or vitamins B(6) and B(12) alone (group A2, 6 autistic children). The homocysteine level in the urine of autistic children before vitamin supplementation was 2.41 ± 1.10 mmol/mol creatinine (mean ± SD difference). After treatment, the homocysteine level was reduced to 1.13 ± 0.44 and 1.33 ± 0.39 mmol/mol creatinine for A1 and A2 groups, respectively. The intake of vitamins B(6) and B(12), together with folic acid, was found to be more effective in lowering the levels of urinary homocysteine than the intake of vitamins B(6) and B(12) alone. Our findings may lead to the recommendation of including vitamins B(6) and B(12) together with folic acid supplementation in the diets of children with autism.

  3. Rapid evaluation of fibrinogen levels using the CG02N whole blood coagulation analyzer.

    PubMed

    Hayakawa, Mineji; Gando, Satoshi; Ono, Yuichi; Mizugaki, Asumi; Katabami, Kenichi; Maekawa, Kunihiko; Miyamoto, Daisuke; Wada, Takeshi; Yanagida, Yuichiro; Sawamura, Atsushi

    2015-04-01

    Rapid evaluation of fibrinogen (Fbg) levels is essential for maintaining homeostasis in patients with massive bleeding during severe trauma and major surgery. This study evaluated the accuracy of fibrinogen levels measured by the CG02N whole blood coagulation analyzer (A&T Corporation, Kanagawa, Japan) using heparinized blood drawn for blood gas analysis (whole blood-Fbg). A total of 100 matched pairs of heparinized blood samples and citrated blood samples were simultaneously collected from patients in the intensive care unit. Whole blood-Fbg results were compared with those of citrated plasma (standard-Fbg). The whole blood coagulation analyzer measured fibrinogen levels within 2 minutes. Strong correlations between standard-Fbg and whole blood-Fbg were observed (ρ = 0.91, p < 0.001). Error grid analysis showed that 88% of the values were clinically acceptable, and 12% were in a range with possible effects on clinical decision-making; none were in a clinically dangerous range without appropriate treatment. Using a fibrinogen cutoff value of 1.5 g/L for standard-Fbg, the area under the receiver operating characteristic curve of whole blood-Fbg was 0.980 (95% confidence interval 0.951-1.000, p < 0.001). The whole blood coagulation analyzer can rapidly measure fibrinogen levels in heparinized blood and could be useful in critical care settings where excessive bleeding is a concern.

  4. Association between Plasma Homocysteine Levels and Neuronal Injury in HIV Infection

    PubMed Central

    Ahlgren, Erika; Hagberg, Lars; Fuchs, Dietmar; Andersson, Lars-Magnus; Nilsson, Staffan; Zetterberg, Henrik; Gisslén, Magnus

    2016-01-01

    Objective To investigate the role of homocysteine in neuronal injury in HIV infection. Methods Using a cross-sectional design and archived samples, we compared concentrations of plasma homocysteine and cerebrospinal fluid (CSF) neurofilament light protein (NFL), a sensitive marker of neuronal injury, in 83 HIV-1-infected subjects without antiretroviral treatment. We also analyzed plasma vitamin B12, serum folate, CSF, and plasma HIV RNA, the immune activation marker neopterin in CSF and serum, and albumin ratio as a marker of blood-brain barrier integrity. Twenty-two subjects provided a second sample median of 12.5 months after antiretroviral treatment initiation. Results A significant correlation was found between plasma homocysteine and CSF NFL concentrations in untreated individuals (r = 0.52, p < 0.0001). As expected, there was a significant inverse correlation between homocysteine and B12 (r = –0.41, p < 0.001) and folate (r = –0.40, p = < 0.001) levels. In a multiple linear regression analysis homocysteine stood out as an independent predictor of CSF NFL in HIV-1-infected individuals. The correlation of plasma homocysteine and CSF NFL was also present in the group receiving antiretroviral therapy (r = 0.51, p = 0.016). Conclusion A correlation between plasma homocysteine and axonal injury, as measured by CSF NFL, was found in both untreated and treated HIV. While this study is not able to prove a causal link, homocysteine and functional B12/folate deficiency appear to play a role in neural injury in HIV-infected individuals. PMID:27441551

  5. Elevated plasma homocysteine level is possibly associated with skin sclerosis in a series of Japanese patients with systemic sclerosis.

    PubMed

    Motegi, Sei-Ichiro; Toki, Sayaka; Yamada, Kazuya; Uchiyama, Akihiko; Ishikawa, Osamu

    2014-11-01

    Homocysteine is a sulfhydryl-containing amino acid that is derived from dietary methionine, and there has been increasing evidence that elevated plasma homocysteine levels are associated with increased risk of cardiovascular diseases, including carotid, coronary and peripheral arterial disease (PAD). The association of plasma homocysteine levels with peripheral vascular involvements, such as Raynaud phenomenon (RP), digital ulcers (DU) in systemic sclerosis (SSc) patients has not been well studied. The objective of this study was to examine plasma homocysteine levels and their clinical associations in patients with SSc. Plasma homocysteine levels in 151 Japanese patients with SSc and 20 healthy controls were examined. No significant differences were observed in plasma homocysteine levels between SSc patients and healthy individuals. Demographic and clinical features of the SSc patients revealed that severe skin sclerosis, anti-topoisomerase I antibody positivity, complications of DU, acro-osteolysis (AO) and interstitial lung disease (ILD) were significantly more prevalent among the patients with elevated plasma homocysteine levels. The plasma homocysteine levels were positively correlated with modified Rodnan total skin score. The plasma homocysteine levels in the SSc patients with DU, AO and ILD were significantly higher than those in the SSc without DU, AO and ILD, respectively. Plasma homocysteine levels did not correlate with either the mean or max intima-media thickness (IMT) or plaque score, suggesting that plasma homocysteine levels might not be associated with carotid artery atherosclerosis in SSc patients. The measurement of plasma homocysteine levels in SSc patients might be useful for the risk stratifications of severe skin sclerosis, DU and AO.

  6. What is the influence of hormone therapy on homocysteine and crp levels in postmenopausal women?

    PubMed Central

    Lakryc, Eli Marcelo; Machado, Rogério Bonassi; Soares, José Maria; Fernandes, César Eduardo; Baracat, Edmund Chada

    2015-01-01

    OBJECTIVE: To evaluate the influence of estrogen therapy and estrogen-progestin therapy on homocysteine and C-reactive protein levels in postmenopausal women. METHODS: In total, 99 postmenopausal women were included in this double-blind, randomized clinical trial and divided into three groups: Group A used estrogen therapy alone (2.0 mg of 17β-estradiol), Group B received estrogen-progestin therapy (2.0 mg of 17 β-estradiol +1.0 mg of norethisterone acetate) and Group C received a placebo (control). The length of treatment was six months. Serum measurements of homocysteine and C-reactive protein were carried out prior to the onset of treatment and following six months of therapy. RESULTS: After six months of treatment, there was a 20.7% reduction in homocysteine levels and a 100.5% increase in C-reactive protein levels in the group of women who used estrogen therapy. With respect to the estrogen-progestin group, there was a 12.2% decrease in homocysteine levels and a 93.5% increase in C-reactive protein levels. CONCLUSION: Our data suggested that hormone therapy (unopposed estrogen or estrogen associated with progestin) may have a positive influence on decreasing cardiovascular risk due to a significant reduction in homocysteine levels. PMID:25789519

  7. Homocysteine levels in morbidly obese patients: its association with waist circumference and insulin resistance.

    PubMed

    Vayá, Amparo; Rivera, Leonor; Hernández-Mijares, Antonio; de la Fuente, Miguel; Solá, Eva; Romagnoli, Marco; Alis, R; Laiz, Begoña

    2012-01-01

    The association between morbid obesity and hyperhomocysteinemia (HH) remains controversial and the nature of this relationship needs to be clarified as several metabolic, lipidic, inflammatory and anthropometric alterations that accompany morbid obesity may be involved. In 66 morbidly obese patients, 47 women and 19 men aged 41 ± 12 years and 66 normo-weight subjects, 43 women and 23 men, aged 45 ± 11 years, we determined homocysteine (Hcy) levels along with lipidic, anthropometric, inflammatory and insulin resistance markers. In addition, we investigated the effect of Metabolic Syndrome (MS) and its components on Hcy levels. Obese patients had statistically higher Hcy levels than controls: 12.76 ± 5.30 μM vs. 10.67 ± 2.50 μM; p = 0.006. Moreover, morbidly obese subjects showed higher waist circumference, glucose, insulin, HOMA, leptin, triglycerides, fibrinogen, C reactive protein (CRP) (p < 0.001, respectively), and lower vitamin B12 (p = 0.002), folic acid and HDL-cholesterol (p < 0.001, respectively). In the multivariate regression analysis, waist circumference, glucose, leptin and folic acid levels were independent predictors for Hcy values (p < 0.050). When obese patients were classified as having MS or not, no differences in Hcy levels were found between the two groups (p = 0.752). Yet when we analysed separately each MS component, only abdominal obesity was associated with Hcy levels (p = 0.031). Moreover when considering glucose >110 mg/dL (NCEP-ATPIII criteria) instead of glucose intolerance >100 mg/dl (updated ATPIII criteria), it also was associated with HH (p = 0.042). These results were confirmed in the logistic regression analysis where abdominal obesity and glucose >115 mg/dL constitute independent predictors for HH (OR = 3.2; CI: 1.23-13.2; p = 0.032, OR: 4.6; CI: 1.7-22.2; p = 0.016, respectively). The results of our study indicate that increased Hcy levels are related mostly with abdominal obesity and with insulin resistance. Thus, HH may

  8. High levels of homocysteine results in cerebral amyloid angiopathy in mice.

    PubMed

    Li, Jian-Guo; Praticò, Domenico

    2015-01-01

    High levels of homocysteine is a risk factor for developing Alzheimer's disease (AD), and the effect that this amino acid has on amyloid-β (Aβ) protein precursor metabolism is considered one of the potential mechanism(s) involved in this effect. However, despite consistent literature indicating that this condition results in brain parenchyma amyloidosis, no data are available on whether it may also influence the amount of Aβ deposited in the vasculature. To test this hypothesis, we implemented a model of diet-inducing high homocysteinemia in AD transgenic mice, 3xTg, and assessed them for the development of cerebral amyloid angiopathy (CAA). Compared with controls, mice with high homocysteine showed a significant increase in the amount of Aβ deposited in the brain vasculature, which was not associated with histological evidence of microhemorrhage occurrence. Mice with high homocysteine had a significant reduction in steady state level of the apolipoprotein E, which is a main Aβ chaperon protein, but no changes in its receptor, the low-density-lipoprotein-receptor-1. Our data demonstrate that a diet-induced high homocysteine level favors the development of CAA via a reduction of Aβ clearance and transport within the brain. Therapeutic approaches aimed at restoring brain apolipoprotein E levels should be considered in individuals carrying this environmental risk factor in order to reduce the incidence of homocysteine-dependent CAA. PMID:25061050

  9. Poor nutrition and alcohol consumption are related to high serum homocysteine level at post-stroke

    PubMed Central

    Choi, Seung-Hye; Kim, Min-Sun; Kim, Jong-Sung

    2015-01-01

    BACKGROUND/OBJECTIVES Increased serum homocysteine (Hcy) levels have been reported to be related to the occurrence of cardio- and cerebrovascular diseases. High serum Hcy levels are also related to the development of secondary stroke and all-cause mortality. The purpose of this study was to investigate the prevalence of high serum homocysteine level and relating factors, and the change over the 10 month period post-stroke. SUBJECTS/METHODS Consecutive stroke patients who were admitted to the Asan Medical Center were enrolled. Ten months after the onset of stroke, an interview with a structured questionnaire was performed and blood samples were obtained for the biochemical parameters. Nutritional status was determined using the mini nutritional assessment (MNA) score and dietary nutrient intakes were also obtained using a 24 hour recall method. RESULTS Out of 203 patients, 84% were malnourished or at risk of malnutrition, and 26% had high homocysteine levels at 10 months post-stroke. Using logistic regression, the factors related with high homocysteine levels at 10 months post-stroke included heavy alcohol consumption (P = 0.020), low MNA scores (P = 0.026), low serum vitamin B12 (P = 0.021) and low serum folate levels (P = 0.003). Of the 156 patients who had normal homocysteine levels at admission, 36 patients developed hyperhomocysteinemia 10 months post-stroke, which was related to heavy alcohol consumption (P = 0.013). Persistent hyperhomocysteinemia, observed in 22 patients (11%), was related to male sex (P = 0.031), old age (P = 0.042), low vitamin B6 intake (P = 0.029), and heavy alcohol consumption (P = 0.013). CONCLUSION Hyperhomocysteinemia is common in post-stroke, and is related to malnutrition, heavy alcohol drinking and low serum level of folate and vitamin B12. Strategies to prevent or manage high homocysteine levels should consider these factors. PMID:26425280

  10. Changes in plasma methionine and total homocysteine levels in patients receiving methotrexate infusions.

    PubMed

    Broxson, E H; Stork, L C; Allen, R H; Stabler, S P; Kolhouse, J F

    1989-11-01

    Methotrexate reduces intracellular pools of 5-methyltetrahydrofolate and could result in reduced conversion of homocysteine to methionine by methionine synthetase. This study was designed to investigate the effects of moderate dose to very high dose methotrexate on methionine and total homocysteine as reflections of methotrexate induced intracellular events. Methionine and total homocysteine were measured prior to, during, and following twenty-six 24-h i.v. infusions of 33.6 g/m2 methotrexate (very high dose methotrexate) in 16 children with acute lymphocytic leukemia and seven 4-h i.v. infusions of 8 g/m2 methotrexate (high dose methotrexate) in 5 children with osteogenic sarcoma. Amino acids were measured by gas chromatography/mass spectrophotometry. Mean methionine levels decreased by 70.0 +/- 3.1% (SE) with very high dose methotrexate and 72.6 +/- 5.9% with high dose methotrexate at 24 and 4.5 h, respectively, after beginning methotrexate infusions. Mean total homocysteine levels increased by 61.7 +/- 3.1% with very high dose methotrexate and 55.6 +/- 17.5% with high dose methotrexate at 36 and 24 h, respectively, after beginning methotrexate infusions. No consistent or significant changes were noted in levels of total cysteine, leucine, isoleucine, or valine. Similar changes did not occur in patients receiving prednisone, vincristine, daunomycin, and intrathecal methotrexate as therapy for acute lymphocytic leukemia. These changes in homocysteine and methionine may reflect biological effects of methotrexate that may predict cytotoxicity of methotrexate.

  11. Signal transduction pathways in erythrocyte nitric oxide metabolism under high fibrinogen levels

    NASA Astrophysics Data System (ADS)

    Saldanha, Carlota; Freitas, T.; Lopez de Almeida, J. P.; Silva-Herdade, A.

    2014-05-01

    Previous studies show that the fibrinogen molecule modulates the metabolism of nitric oxide (NO) in erythrocyte. The in vitro induced hiperfibrinogenemia interferes in the metabolism of the NO in the erythrocyte in dependence of the phosphorylation degree of the band 3. The soluble form of fibrinogen binds into CD47 protein present in the erythrocyte membrane. The soluble thrombomodulin is an inflammatory marker that binds to the erythrocyte CD47 in a site with a sequence peptide known as 4N1K. A study done in vitro shows that when hiperfibrinogenemia was induced in the presence of the peptide 4N1K agonist of CD47 it were observed variations in the efflux of NO from erythrocyte and an increase in the concentrations of GSNO, peroxinitrite, nitrite and nitrate of the erythrocytes. The aim of this work was to study the influence of the peptide 4N1K, on the metabolism of NO in the erythrocyte under high fibrinogen concentration and in the presence of inhibitors of the status of phosphorylation of protein band 3. In this in vitro study, whole blood samples were harvested from healthy subjects and NO, peroxynitrite, nitrite, nitrate and S-nitro-glutathione (GSNO) were determined in presence of 4N1K, calpeptine, Syk inhibitor and under high fibrinogen concentrations. The results obtained in erythrocytes under high fibrinogen levels when 4N1K is present with the Syk inhibitor or with calpeptine, showed in relation to the control samples increased significant concentrations of efflux of NO and of peroxynitrite, nitrite, nitrate and GSNO. In conclusion it was verified that in the in vitro model of hiperfibrinogenemia the peptide 4N1K, agonist of CD47, induces mobilization of NO in the erythrocyte in dependence of the status of phosphorylation of protein band 3.

  12. Trials That Matter: Should We Routinely Measure Homocysteine Levels and “Treat” Mild Hyperhomocysteinemia?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several observational studies involving healthy populations in the 1990s showed positive associations between elevated homocysteine level and increased risk for ischemic heart disease and stroke. Several small trials conducted in western populations in the early and mid-1990s suggested that “daily s...

  13. Serum homocysteine, vitamin B12, folic acid levels and methylenetetrahydrofolate reductase (MTHFR) gene polymorphism in vitiligo.

    PubMed

    Yasar, Ali; Gunduz, Kamer; Onur, Ece; Calkan, Mehmet

    2012-01-01

    The aim of this study was to determine serum vitamin B12, folic acid and homocysteine (Hcy) levels as well as MTHFR (C677, A1298C) gene polymorphisms in patients with vitiligo, and to compare the results with healthy controls. Forty patients with vitiligo and 40 age and sex matched healthy subjects were studied. Serum vitamin B12 and folate levels were determined by enzyme-linked immunosorbent assay. Plasma Hcy levels and MTHFR polymorphisms were determined by chemiluminescence and real time PCR methods, respectively. Mean serum vitamin B12 and Hcy levels were not significantly different while folic acid levels were significantly lower in the control group. There was no significant relationship between disease activity and vitamin B12, folic acid and homocystein levels. No significant difference in C677T gene polymorphism was detected. Heterozygote A1298C gene polymorphism in the patient group was statistically higher than the control group. There was no significant relationship between MTHFR gene polymorphisms and vitamin B12, folic acid and homocysteine levels. In conclusion, vitamin B12, folate and Hcy levels are not altered in vitiligo and MTHFR gene mutations (C677T and A1298C) do not seem to create susceptibility for vitiligo. PMID:22846211

  14. PCOS women show significantly higher homocysteine level, independent to glucose and E2 level

    PubMed Central

    Eskandari, Zahra; Sadrkhanlou, Rajab-Ali; Nejati, Vahid; Tizro, Gholamreza

    2016-01-01

    Background: It is reasonable to think that some biochemical characteristics of follicular fluid (FF) surrounding the oocyte may play a critical role in determining the quality of oocyte and the subsequent potential needed to achieve fertilization and embryo development. Objective: This study was carried out to evaluate the levels of FF homocysteine (Hcy) in IVF candidate polycystic ovary syndrome (PCOS) women and any relationships with FF glucose and estradiol (E2) levels. Materials and Methods: In this case control study which was performed in Dr. Tizro Day Care and IVF Center 70 infertile patients were enrolled in two groups: comprising 35 PCOS and 35 non PCOS women. Long protocol was performed for all patients. FF Hcy, glucose and E2 levels were analyzed at the time of oocyte retrieval. Results: It was observed that FF Hcy level was significantly higher in PCOS patients compared with non PCOSs (p<0.01). Observations demonstrated that in PCOS group, the Hcy level increased independent to E2, glucose levels, BMI and age, while the PCOS group showed significantly higher BMI compared with non-PCOS group (p=0.03). However, no significant differences were revealed between groups for FF glucose and E2 levels. Conclusion: Present data showed that although FF glucose and E2 levels were constant in PCOS and non PCOS patients, but the FF Hcy levels in PCOS were significantly increased (p=0.01). PMID:27679823

  15. PCOS women show significantly higher homocysteine level, independent to glucose and E2 level

    PubMed Central

    Eskandari, Zahra; Sadrkhanlou, Rajab-Ali; Nejati, Vahid; Tizro, Gholamreza

    2016-01-01

    Background: It is reasonable to think that some biochemical characteristics of follicular fluid (FF) surrounding the oocyte may play a critical role in determining the quality of oocyte and the subsequent potential needed to achieve fertilization and embryo development. Objective: This study was carried out to evaluate the levels of FF homocysteine (Hcy) in IVF candidate polycystic ovary syndrome (PCOS) women and any relationships with FF glucose and estradiol (E2) levels. Materials and Methods: In this case control study which was performed in Dr. Tizro Day Care and IVF Center 70 infertile patients were enrolled in two groups: comprising 35 PCOS and 35 non PCOS women. Long protocol was performed for all patients. FF Hcy, glucose and E2 levels were analyzed at the time of oocyte retrieval. Results: It was observed that FF Hcy level was significantly higher in PCOS patients compared with non PCOSs (p<0.01). Observations demonstrated that in PCOS group, the Hcy level increased independent to E2, glucose levels, BMI and age, while the PCOS group showed significantly higher BMI compared with non-PCOS group (p=0.03). However, no significant differences were revealed between groups for FF glucose and E2 levels. Conclusion: Present data showed that although FF glucose and E2 levels were constant in PCOS and non PCOS patients, but the FF Hcy levels in PCOS were significantly increased (p=0.01).

  16. Vitamin B12, folate, homocysteine and urinary methylmalonic acid levels in infants.

    PubMed

    Karademir, F; Suleymanoglu, S; Ersen, A; Aydinoz, S; Gultepe, M; Meral, C; Ozkaya, H; Gocmen, I

    2007-01-01

    Serum vitamin B12 and folate, and their functional markers, plasma homocysteine and urinary methylmalonate (uMMA) were measured in 204 healthy, term infants at birth, and at 2 and 6 months. Compared with infants receiving formula food, those fed mother's milk had lower vitamin B12 and folate at 2 and 6 months. In infants receiving mother's milk, vitamin B12 levels were similar at birth (238 pg/ml) and 2 months (243 pg/ml), whereas with formula milk the level was significantly higher at 2 months (558 pg/ml) than at birth (257 pg/ml). Vitamin B12 was negatively correlated with homocysteine at birth and 6 months. The level of uMMA (mmol/mol creatinine) was higher at 2 (mother's milk, 25.5; formula, 23.97) and 6 months (19.77; 15) than at birth (11.97; 10.88), and was not correlated with vitamin B12 levels. Homocysteine may be a reliable marker of vitamin B12 status in neonates and infants; however, uMMA is not suitable as a marker of vitamin B12 status.

  17. Vascular endothelial dysfunction associated with elevated serum homocysteine levels in rat adjuvant arthritis: effect of vitamin E administration.

    PubMed

    Can, Cenk; Cinar, Mehtap G; Koşay, Sezen; Evinç, Akgün

    2002-06-14

    We aimed to study the alterations in serum homocysteine levels and endothelium-dependent and -independent vascular relaxant responses in adjuvant-induced arthritis of the rat and to determine the effects of vitamin E administration on these changes. Arthritis was induced by a single intradermal injection of Freund's complete adjuvant into the paw. 26 days after the induction of arthritis, serum homocysteine levels and relaxant responses to acetylcholine and sodiumnitroprusside in thoracic aortas were evaluated. The relaxant responses to acetylcholine were decreased in aortas from arthritic rats, whereas the responses to sodiumnitroprusside were not significantly different when compared to the aortas from control rats. A significant increase was observed in serum homocysteine levels of the arthritic rats in comparison to those of controls. Vitamin E administration (100 mg/kg/day, i.m. for 26 days) to arthritic rats resulted in a significant increase in endothelium-dependent aortic responses to acetylcholine and a significant decrease in serum homocysteine levels with respect to the non-treated arthritic rats. However, in healthy rats, vitamin E treatment significantly decreased the acetylcholine-induced relaxant responses. We conclude that adjuvant-induced arthritis in the rat is associated with increased serum homocysteine levels and this is accompanied by a reduction in endothelium-dependent vascular responses in the thoracic aortas. Vitamin E treatment leads to normalization of the increased serum homocysteine levels and improves the endothelium-dependent relaxant responses in this experimental model. PMID:12044840

  18. Nattokinase decreases plasma levels of fibrinogen, factor VII, and factor VIII in human subjects.

    PubMed

    Hsia, Chien-Hsun; Shen, Ming-Ching; Lin, Jen-Shiou; Wen, Yao-Ke; Hwang, Kai-Lin; Cham, Thau-Ming; Yang, Nae-Cherng

    2009-03-01

    Nattokinase, a serine proteinase from Bacillus subtilis, is considered to be one of the most active functional ingredients found in natto. In this study, we hypothesized that nattokinase could reduce certain factors of blood clotting and lipids that are associated with an increase risk for cardiovascular disease (CVD). Thus, an open-label, self-controlled clinical trial was conducted on subjects of the following groups: healthy volunteers (Healthy Group), patients with cardiovascular risk factors (Cardiovascular Group), and patients undergoing dialysis (Dialysis Group). All subjects ingested 2 capsules of nattokinase (2000 fibrinolysis units per capsule) daily orally for 2 months. The laboratory measurements were performed on the screening visit and, subsequently, regularly after the initiation of the study. The intent-to-treat analysis was performed on all 45 enrolled subjects. By use of mixed model analysis, a significant time effect, but not group effect, was observed in the change from baseline of fibrinogen (P = .003), factor VII (P < .001), and factor VIII (P < .001), suggesting that the plasma levels of the 3 coagulation factors continuously declined during intake; also, the extents of decrease were similar between groups. After 2 months of administration, fibrinogen, factor VII, and factor VIII decreased 9%, 14%, and 17%, respectively, for the Healthy Group; 7%, 13%, and 19%, respectively, for the Cardiovascular Group; and 10%, 7%, and 19%, respectively, for the Dialysis Group, whereas blood lipids were unaffected by nattokinase. No significant changes of uric acid or notable adverse events were observed in any of the subjects. In summary, this study showed that oral administration of nattokinase could be considered as a CVD nutraceutical by decreasing plasma levels of fibrinogen, factor VII, and factor VIII.

  19. Homocysteine, folate, and vitamin B12 levels and vertebral fracture risk in postmenopausal women.

    PubMed

    El Maghraoui, Abdellah; Ghozlani, Imad; Mounach, Aziza; Rezqi, Asmaa; Oumghar, Khalid; Achemlal, Lahsen; Bezza, Ahmed; Ouzzif, Zhor

    2012-01-01

    The objective of this study was to examine the influence of homocysteine, vitamin B(12), and folate on the prevalence of asymptomatic osteoporotic vertebral fractures (VFs) using vertebral fracture assessment (VFA) in postmenopausal women. The study cohort consisted of 188 consecutive postmenopausal women (mean age, weight, and body mass index of 57.9 ± 8.5 [41-91]yr, 74.4 ± 13.5 [38-150]kg, and 30.4 ± 5.2 [17.1-50.7]kg/m(2), respectively). Lateral VFA images and scans of the lumbar spine and proximal femur were obtained using a Lunar Prodigy Vision densitometer (GE Healthcare Inc., Waukesha, WI). VFs were defined using a combination of Genant's semiquantitative approach and morphometry. Fifty-eight (30.9%) patients had densitometric osteoporosis. VFs were identified using VFA in 76 (40.4%) patients: 61 women had grade 1 VFs and 15 had grade 2 or 3 VFs. No statistical difference was shown between the 3 groups (absence of VFs, VFs grade 1, and VFs grade 2/3) concerning the biological parameters. Comparison of patients according to quartiles of homocysteine levels showed that women in the highest quartile were older and had a lower bone mineral density (BMD); however, the prevalence of VFs was not statistically different from that of women in the other quartile groups. Stepwise regression analysis showed that homocysteine was not independently associated with the presence of VFs, which was mainly related to the osteoporotic status. Although a weak association was observed between hyperhomocysteinemia and low BMD and a trend to higher prevalence of grade 2/3 VFs was observed, our study did not confirm that homocysteine, vitamin B(12), and folate status are important determinants of prevalent asymptomatic VFs in postmenopausal women.

  20. Elevated Homocysteine Level Related to Poor Outcome After Thrombolysis in Acute Ischemic Stroke.

    PubMed

    Yao, En-Sheng; Tang, Yan; Xie, Min-Jie; Wang, Ming-Huan; Wang, Hong; Luo, Xiang

    2016-01-01

    BACKGROUND Hyperhomocysteinemia (HHcy) is a well-known risk factor for ischemic stroke. However, whether HHcy can influence the treatment outcome of acute ischemic stroke (AIS) patients has yet to be fully determined. In this study, we investigated the relationship between serum homocysteine (Hcy) level and prognosis in AIS patients who received tissue plasminogen activator (tPA) treatment. MATERIAL AND METHODS Patients were recruited according to the research criteria and grouped by their serum Hcy levels. Neurological outcome was evaluated by National Institute of Health Stroke Scale (NIHSS) score system before and 1 week after treatment, and functional outcome was evaluated by modified Rankin Scale (MRS) score system after 3 months. All patients took CT/MRI examination to detect cerebral hemorrhage in 24 hours after tPA treatment. Receiver operating characteristic curve (ROC) was employed to assess if serum homocysteine level can be used as an index to predict the outcome after tPA treatment. RESULTS The mean (±SD) serum Hcy level of 194 patients was 22.62±21.23 μmol/L. After 1-week tPA treatment, the NIHSS scores of high Hcy level group were significantly higher than those of low level group (p<0.05), meantime the high Hcy group showed obvious symptomatic intracerebral hemorrhage risk after 24 hours (p<0.05). Poor outcome was presented in mRS score results after 3 months in high Hcy level group, which compared with low Hcy level group (p<0.01). The ROC showed that Hcy level was a moderately sensitive and specific index to predict the prognosis with an optimal cut-off value at 19.95 µmol/L (sensitivity [58.2%], specificity [80.3%]). CONCLUSIONS High serum homocysteine level could potentially predict poor prognosis in acute ischemic stroke patients after tPA treatment. PMID:27629768

  1. Elevated Homocysteine Level Related to Poor Outcome After Thrombolysis in Acute Ischemic Stroke

    PubMed Central

    Yao, En-Sheng; Tang, Yan; Xie, Min-Jie; Wang, Ming-Huan; Wang, Hong; Luo, Xiang

    2016-01-01

    Background Hyperhomocysteinemia (HHcy) is a well-known risk factor for ischemic stroke. However, whether HHcy can influence the treatment outcome of acute ischemic stroke (AIS) patients has yet to be fully determined. In this study, we investigated the relationship between serum homocysteine (Hcy) level and prognosis in AIS patients who received tissue plasminogen activator (tPA) treatment. Material/Methods Patients were recruited according to the research criteria and grouped by their serum Hcy levels. Neurological outcome was evaluated by National Institute of Health Stroke Scale (NIHSS) score system before and 1 week after treatment, and functional outcome was evaluated by modified Rankin Scale (MRS) score system after 3 months. All patients took CT/MRI examination to detect cerebral hemorrhage in 24 hours after tPA treatment. Receiver operating characteristic curve (ROC) was employed to assess if serum homocysteine level can be used as an index to predict the outcome after tPA treatment. Results The mean (±SD) serum Hcy level of 194 patients was 22.62±21.23 μmol/L. After 1-week tPA treatment, the NIHSS scores of high Hcy level group were significantly higher than those of low level group (p<0.05), meantime the high Hcy group showed obvious symptomatic intracerebral hemorrhage risk after 24 hours (p<0.05). Poor outcome was presented in mRS score results after 3 months in high Hcy level group, which compared with low Hcy level group (p<0.01). The ROC showed that Hcy level was a moderately sensitive and specific index to predict the prognosis with an optimal cut-off value at 19.95 μmol/L (sensitivity [58.2%], specificity [80.3%]). Conclusions High serum homocysteine level could potentially predict poor prognosis in acute ischemic stroke patients after tPA treatment. PMID:27629768

  2. Correlation between C677T MTHFR gene polymorphism, plasma homocysteine levels and the incidence of CAD.

    PubMed

    Nakai, K; Itoh, C; Nakai, K; Habano, W; Gurwitz, D

    2001-01-01

    The lesions of coronary atherosclerosis represent the result of a complex, multicellular, inflammatory-healing response in the coronary arterial wall. In vivo and in vitro cellular and molecular studies have suggested a role for tissue homocysteine in endothelial cell injury and adverse extra-cellular matrix remodeling. Gene polymorphisms in relation with numerous risk factors might increase the incidence of coronary artery disease (CAD). In this review we have focused on the correlations between plasma homocysteine levels, the incidence of cardiovascular disease and the cytosine-to-thymidine substitution at nucleotide 677 (C677T) of the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, coding for a key enzyme in methionine-homocysteine metabolism. The role of the C677T MTHFR gene polymorphism in the causation of CAD is controversial. We reviewed 12 recent case-control studies comprising 5370 genotyped patients with CAD and 4961 genotyped participants without CAD. There was no significant difference between those with and without CAD in the frequency of the C677T polymorphism (34.9 vs 33.6%). The frequency of homozygous C677T polymorphism in these groups was 10.9 versus 12.8%, respectively, although there were some ethnic differences in the C677T MTHFR polymorphism. In the analysis of the 12 studies, the odds ratio of CAD associated with the TT genotype (homozygous C677T polymorphism) was 1.18. Only slightly higher plasma homocysteine levels were observed in participants with the val/val (TT) genotype (14.4+/-2.9 micro mol/L in TT genotype vs 11.1+/-1.9 and 11.9+/-2 micro mol/L in CC and CT genotype, respectively). In addition, the relation between homocysteine increase after methionine loading and MTHFR genotypes is also controversial. However, hyperhomocysteinemia because of the C677T MTHFR allele may be corrected with oral folic acid therapy. Further investigations on the relationships between MTHFR genotypes and the incidence of CAD should be based on

  3. Cognitive impairment and its association with homocysteine plasma levels in females with eating disorders - findings from the HEaD-study.

    PubMed

    Frieling, H; Röschke, B; Kornhuber, J; Wilhelm, J; Römer, K D; Gruss, B; Bönsch, D; Hillemacher, T; de Zwaan, M; Jacoby, G E; Bleich, S

    2005-11-01

    Higher plasma homocysteine levels have been found in females with anorexia nervosa. Furthermore, elevated homocysteine levels are associated with cognitive decline in dementia and healthy elderly people. Aim of this prospective study was to investigate a possible association between homocysteine serum levels and Clinically well known cognitive deficits in females with eating disorders. We found that moderately elevated plasma homocysteine levels were associated with normal short- and long-term verbal memory while normal plasma homocysteine levels were associated with poorer memory performance in 14 females with anorexia nervosa and 12 females with bulimia nervosa (logistic forward regression Wald chi(2)=8.566, OR=24.75, CI 2.89 - 212.23, P=0.003). These results indicate that under the special circumstances of eating disorders elevated homocysteine levels improve memory signaling possibly by facilitating long-term potentiation.

  4. Effect of plasma homocysteine level and urinary monomethylarsonic acid on the risk of arsenic-associated carotid atherosclerosis

    SciTech Connect

    Wu, M.-M.; Chiou, H.-Y. . E-mail: hychiou@tmu.edu.tw; Hsueh, Y.-M.; Hong, C.-T.; Su, C.-L.; Chang, S.-F.; Huang, W.-L.; Wang, H.-T.; Wang, Y.-H.; Hsieh, Y.-C.; Chen, C.-J.

    2006-10-01

    Arsenic-contaminated well water has been shown to increase the risk of atherosclerosis. Because of involving S-adenosylmethionine, homocysteine may modify the risk by interfering with the biomethylation of ingested arsenic. In this study, we assessed the effect of plasma homocysteine level and urinary monomethylarsonic acid (MMA{sup V}) on the risk of atherosclerosis associated with arsenic. In total, 163 patients with carotid atherosclerosis and 163 controls were studied. Lifetime cumulative arsenic exposure from well water for study subjects was measured as index of arsenic exposure. Homocysteine level was determined by high-performance liquid chromatography (HPLC). Proportion of MMA{sup V} (MMA%) was calculated by dividing with total arsenic species in urine, including arsenite, arsenate, MMA{sup V}, and dimethylarsinic acid (DMA{sup V}). Results of multiple linear regression analysis show a positive correlation of plasma homocysteine levels to the cumulative arsenic exposure after controlling for atherosclerosis status and nutritional factors (P < 0.05). This correlation, however, did not change substantially the effect of arsenic exposure on the risk of atherosclerosis as analyzed in a subsequent logistic regression model. Logistic regression analyses also show that elevated plasma homocysteine levels did not confer an independent risk for developing atherosclerosis in the study population. However, the risk of having atherosclerosis was increased to 5.4-fold (95% CI, 2.0-15.0) for the study subjects with high MMA% ({>=}16.5%) and high homocysteine levels ({>=}12.7 {mu}mol/l) as compared to those with low MMA% (<9.9%) and low homocysteine levels (<12.7 {mu}mol/l). Elevated homocysteinemia may exacerbate the formation of atherosclerosis related to arsenic exposure in individuals with high levels of MMA% in urine.

  5. Evaluation of an Association of Blood Homocysteine Levels With Gastric Cancer Risk From 27 Case–Control Studies

    PubMed Central

    Xu, Wei; Cheng, Yuelei; Zhu, Huirong

    2016-01-01

    Abstract High blood homocysteine levels may risk gastric cancer. However, observational studies have been plagued by chance, bias, confounding, or reverse causality. In this study, we assessed the relationship between blood homocysteine levels and gastric cancer by using a Mendelian randomization method, which is independent of nongenetic confounding. We took 2 steps to perform Mendelian randomization analysis. First, we evaluated the methylenetetrahydrofolate reductase (MTHFR) C677T association with gastric cancer by a meta-analysis of case-control studies including 7566 patients with gastric cancer and 10 640 control subjects from 27 Case–Control studies. Second, MTHFR C677T polymorphism, which affects the blood homocysteine levels, was used as an instrumental variable to calculate the risk and estimate the association of gastric cancer with this single nucleotide polymorphism (SNP). We obtained an estimate to the association of blood total homocysteine levels with this SNP from a meta-analysis of Genome-Wide Association Studies (GWAS), which comprises a total of 44 147 individuals. In our Mendelian randomization analysis, we demonstrated a significant effect of the blood homocysteine levels on gastric cancer risk, representing an OR of 2.56 (95% CI = 2.41–2.72; P = 5.0×10−4) for gastric cancer per 1-SD increase in the natural log-transformed blood total homocysteine levels. We proved that there is a causal relationship between blood total homocysteine and risk of gastric cancer, and this study will add insight into the treatment and pathology research of gastric cancer. PMID:27196483

  6. Increased plasma homocysteine levels in patients with multiple sclerosis and depression

    PubMed Central

    Triantafyllou, Nikolaos; Evangelopoulos, Maria-Eleftheria; Kimiskidis, Vasilios K; Kararizou, Evangelia; Boufidou, Fotini; Fountoulakis, Konstantinos N; Siamouli, Melina; Nikolaou, Chrysoula; Sfagos, Constantinos; Vlaikidis, Nikolaos; Vassilopoulos, Dimitrios

    2008-01-01

    Background The aim of the study was to assess the plasma levels of homocysteine in patients with multiple sclerosis (MS) and to investigate whether an association with depression exists. Methods Plasma homocysteine (Hcy), vitamin B12 and plasma folate were measured in 65 moderately disabled patients with relapsing/remitting MS (RR-MS) and 60 healthy controls. All subjects were assessed with the Beck Depression Inventory (BDI). Results Hcy levels were significantly increased in MS patients compared to controls (13.5 ± 4.7 μmol/l vs 8.5 ± 3.1, p < 0.001). A significant correlation was found between Hcy levels and BDI scores (Pearson r = 0.3025, p < 0.05). Plasma Hcy was not related to Extended Disability Status Scale (EDSS) score, age, disease duration or vitamin B12 and folate. Conclusion Moderately disabled MS patients with elevated Hcy levels are particularly prone to develop depressive symptomatology. Further study is warranted in order to elucidate the prognostic and therapeutic implications of this novel finding. PMID:18782433

  7. The estimation of fibrinogen levels in animal plasmas by a simple refractometric method. A comparison with a biuret method.

    PubMed

    Sutton, R H

    1977-05-01

    A comparison was made between a biuret (reference) method and a simple refractometric (test) method for measuring fibrinogen levels in 84 animal plasmas. Although the correlation between the two methods was high (4=0.90 P less than 0-001) there was considerable random variation in the refractometric results in relation to the biuret results. This was thought to be due in part to the fact that refractometric results could only be expressed in multiples of 2.4 g/litre. In spite of this limitation, the refractometric method, on the grounds of speen and simplicity, is considered to have worthwhile application for fibrinogen determinations in practice laboratory.

  8. Association of homocysteine level with biopsy-proven non-alcoholic fatty liver disease: a meta-analysis

    PubMed Central

    Dai, Yining; Zhu, Jinzhou; Meng, Di; Yu, Chaohui; Li, Youming

    2016-01-01

    Previous studies have reported inconsistent findings regarding the association between plasmatic higher of homocysteine level and non-alcoholic fatty liver disease. We aimed to investigate this association by conducting a meta-analysis. Literature was searched on PubMed from inception to January 2015. Eight studies evaluating plasma level of homocysteine in biopsy-proven non-alcoholic fatty liver disease subjects compared to healthy controls were included. Compared with the controls, non-alcoholic fatty liver disease patients witnessed a higher level of homocysteine [standard mean difference (SMD): 0.66 µmol/L, 95% CI: 0.41, 0.92 µmol/L], and were associated with a significant increased risk for hyperhomocysteinemia [odds ratio (OR) 5.09, 95% CI: 1.69, 15.32]. In addition, patients with non-alcoholic fatty liver presented 0.45 µmol/L higher levels of homocysteine compared to healthy controls (95% CI: 0.09, 0.82 µmol/L), whereas non-alcoholic steatohepatitis patients had 1.02 µmol/L higher levels of homocysteine (95% CI: 0.28, 1.76 µmol/L). There was neither difference of folate level nor vitamin B12 level between non-alcoholic fatty liver disease subjects and healthy controls. This study revealed that non-alcoholic fatty liver disease patients presented an increased serum concentration of homocysteine, and were associated with an increased risk of hyperhomocysteinemia. Further studies are needed to demonstrate a causal role of hyperhomocysteinemia in non-alcoholic fatty liver disease. PMID:26798201

  9. Effect of body weight on serum homocysteine level in patients with polycystic ovarian syndrome: A case control study

    PubMed Central

    I. Al- Gareeb, Ali; Abd Al- Amieer, Wafaa Salah; M. Alkuraishy, Hayder; J. Al- Mayahi, Thabat

    2016-01-01

    Background: Polycystic ovarian syndrome (PCOS) represent one of the common endocrine disorders which influence around 8% of reproductive women whom usually suffering from obesity and increase cardiovascular risk. Serum homocysteine levels are associated with bad impact on endothelial functions and considered as an independent risk factor for cardiovascular disease. Objective: The aim was to study the level of plasma homocysteine in obese and non-obese Iraqi patients with PCOS. Materials and Methods: This study was carried out on 207 women. Of theme, 101 women with PCOS and 106 PCOS- free women served as controls. Blood sample was taken from each participant on the 2nd day of menstruation morning after an overnight fasting. Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), free testosterone and androstenedione were measured. Moreover, total lipid profile and plasma homocysteine levels were measured in both groups. Results: Sixty percent of PCOS women were overweight or obese and 56% of them had a waist circumference >88cm. Moreover plasma homocysteine concentrations were found to be higher in patients with PCOS (11.5±5.41μmol/L) as compared with control (8.10±1.89 μmol/L) (p<0.002). Furthermore the homocysteine concentrations were 13.19±5.97 μmol/L and 9.38±2.99 μmol/L in both obese and normal-weight PCOS women respectively which was significantly higher than obese (p<0.002) and normal-weight (p<0.004) control women. Conclusion: Increase in body weight is not an independent risk factor to increase plasma homocysteine levels in PCOS women. PMID:27200421

  10. Relation between admission plasma fibrinogen levels and mortality in Chinese patients with coronary artery disease

    PubMed Central

    Peng, Yong; Wang, Hua; Li, Yi-ming; Huang, Bao-tao; Huang, Fang-yang; Xia, Tian-li; Chai, Hua; Wang, Peng-ju; Liu, Wei; Zhang, Chen; Chen, Mao; Huang, De-jia

    2016-01-01

    Fibrinogen (Fib) was considered to be a potential risk factor for the prognosis of patients with coronary artery disease (CAD), but there was lack of the evidence from Chinese contemporary population. 3020 consecutive patients with CAD confirmed by coronary angiography were enrolled and were grouped into 2 categories by the optimal Fib cut-off value (3.17 g/L) for all-cause mortality prediction. The end points were all-cause mortality and cardiac mortality. Cumulative survival curves showed that the risk of all-cause mortality was significantly higher in patients with Fib ≥3.17 g/L compared to those with Fib <3.17 g/L (mortality rate, 11.5% vs. 5.7%, p < 0.001); and cardiovascular mortality obtained results similar to those mentioned above (cardiac mortality rate, 5.9% vs. 3.6%, p = 0.002). Subgroup analysis showed that elevated Fib levels were predictive for the risk of all-cause mortality in the subgroups according to age, medical history, and diagnosis. COX multivariate regression analysis showed that plasma Fib levels remained independently associated with all-cause mortality after adjustment for multiple cardiovascular risk factors (all-cause mortality, HR 2.01, CI 1.51–2.68, p < 0.001). This study has found that Fib levels were independently associated with the mortality risk in Chinese CAD patients. PMID:27456064

  11. Association Between Serum B12 and Serum Homocysteine Levels in Diabetic Patients on Metformin

    PubMed Central

    Kothari, Nitin; Shah, Hitesh

    2016-01-01

    Introduction Type-2 Diabetes Mellitus (T2DM) and metformin both can lower serum B12 (s.B12). Raised serum Homocysteine (s.Hcy) is considered as an early marker of B12 deficiency. Aim The study aimed to check whether homocysteine levels are more sensitive indicator of s. B12 deficiency or not among diabetics using metformin. Materials and Methods Mean s.B12 and s.Hcy levels of 30 cases (diabetics on metformin <5years) were compared with 30 diabetic controls not on metformin and 31 nondiabetic controls and statistically analysed by ANOVA and post-hoc tests. Results No significant differences in either s.B12 mean or s.Hcy mean were found between cases and diabetic controls. s.B12 mean did not differ significantly but s.Hcy mean was significantly higher among nondiabetics as compared to diabetic control. s. B12 level of Nondiabetic group was in borderline category while mean s. B12 levels of cases and diabetic control groups was in normal category but nearer to the lower cut off. Mean s.Hcy values in all the groups were high. Pearson correlation showed strong association between s.B12 and s.Hcy in all the groups. Additionally equation based on linear regression was derived to calculate either of the s.B12 or s.Hcy. On Receiver Operative Characteristic (ROC) curve, area under curve value was 0.842 for the value of s.Hcy. Conclusion In this study neither metformin nor T2DM could be identified as a cause for s.B12 lowering and raised s.Hcy in the scenario of low normal levels of s.B12 (<300pmol/L). If B12 deficiency recognized early using s. Hcy, consequences due to B12 deficiency can be prevented or delayed among nondiabetics as well as among diabetics and metformin users. PMID:27190787

  12. Critical levels of brain atrophy associated with homocysteine and cognitive decline.

    PubMed

    de Jager, Celeste A

    2014-09-01

    Few B-vitamin trials to lower homocysteine (Hcy) have reported evidence of beneficial effects on cognition in older adults with cognitive impairment or Alzheimer's disease. This article reviews the role of Hcy in cognitive decline. It also considers some reasons why meta-analyses have failed to find effects of B-vitamin treatment. Findings from the successful VITACOG trial are examined from a new perspective of critical levels of Hcy and brain atrophy that may impact on the efficacy of B-vitamin treatment. It appears that there is a critical level of brain shrinkage, possibly mediated by elevated Hcy, which when reached, results in cognitive decline, especially in episodic memory performance. Supplements, food sources, and effects of folic acid fortification are discussed in relation to B12 deficiency.

  13. Regular Exercise Training Increases the Number of Endothelial Progenitor Cells and Decreases Homocysteine Levels in Healthy Peripheral Blood

    PubMed Central

    Choi, Jeong Kyu; Moon, Ki Myung; Jung, Seok Yun; Kim, Ji Yong; Choi, Sung Hyun; Kim, Da Yeon; Kang, Songhwa; Chu, Chong Woo

    2014-01-01

    Endothelial progenitor cells (EPCs) are known to play an important role in the repair of damaged blood vessels. We used an endothelial progenitor cell colony-forming assay (EPC-CFA) to determine whether EPC numbers could be increased in healthy individuals through regular exercise training. The number of functional EPCs obtained from human peripheral blood-derived AC133 stem cells was measured after a 28-day regular exercise training program. The number of total endothelial progenitor cell colony-forming units (EPC-CFU) was significantly increased compared to that in the control group (p=0.02, n=5). In addition, we observed a significant decrease in homocysteine levels followed by an increase in the number of EPC-CFUs (p=0.04, n=5), indicating that the 28-day regular exercise training could increase the number of EPC colonies and decrease homocysteine levels. Moreover, an inverse correlation was observed between small-endothelial progenitor cell colony-forming units (small-EPC-CFUs) and plasma homocysteine levels in healthy men (r=-0.8125, p=0.047). We found that regular exercise training could increase the number of EPC-CFUs and decrease homocysteine levels, thus decreasing the cardiovascular disease risk in men. PMID:24757379

  14. Traditional and alternative nutrition--levels of homocysteine and lipid parameters in adults.

    PubMed

    Krajcovicová-Kudlácková, M; Blazícek, P; Babinská, K; Kopcová, J; Klvanová, J; Béderová, A; Magálová, T

    2000-12-01

    Values of homocysteine and lipid parameters were measured in groups of adults consuming alternative nutrition (vegetarians/lactoovo/, vegans) and compared with a group consuming traditional diet (omnivores, general population). Frequency of hyperhomocysteinemia was 53% in the vegans group, 28% in vegetarians vs. 5% in omnivores. In conditions of lower methionine intake (reduced content in plant proteins), the remethylation pathway of homocysteine metabolism prevails and it is vitamin B12 and folate-dependent. The intake of vitamin B12 is equal to zero in vegans; vegetarians consume 124% of the RDA vs. 383% in omnivores. Serum vitamin levels are significantly lower in subjects consuming alternative nutrition with deficiency observed in 24% of vegetarians, 78% of vegans vs. 0% in omnivores. Serum folate levels are within the reference range in all groups. Mild hyperhomocysteinemia in the groups consuming alternative diet is a consequence of vitamin B12 deficiency. Vegetarians and vegans meet the RDA for energy and fat, and have a favourable proportion of saturated, mono- and polyunsaturated fatty acids on total energy intake; the ratio of linoleic/alpha-linolenic acid in their diet corresponds with the recommendations. They have low cholesterol consumption and higher vitamin E and C intake. Optimal fat intake of correct composition is reflected in lower values of atherosclerosis risk factors (cholesterol, LDL-cholesterol, atherogenic index, saturated fatty acids, triacylglycerols), and significantly higher levels of protective substances (linoleic acid, alpha-linolenic acid, HDL-cholesterol, vitamin E, vitamin E/cholesterol, vitamin C). Low lipid risk factors but higher findings of mild hyperhomocysteinemia in vegetarians mean a diminished protective effect of alternative nutrition in cardiovascular disease prevention.

  15. Traditional and alternative nutrition--levels of homocysteine and lipid parameters in adults.

    PubMed

    Krajcovicová-Kudlácková, M; Blazícek, P; Babinská, K; Kopcová, J; Klvanová, J; Béderová, A; Magálová, T

    2000-12-01

    Values of homocysteine and lipid parameters were measured in groups of adults consuming alternative nutrition (vegetarians/lactoovo/, vegans) and compared with a group consuming traditional diet (omnivores, general population). Frequency of hyperhomocysteinemia was 53% in the vegans group, 28% in vegetarians vs. 5% in omnivores. In conditions of lower methionine intake (reduced content in plant proteins), the remethylation pathway of homocysteine metabolism prevails and it is vitamin B12 and folate-dependent. The intake of vitamin B12 is equal to zero in vegans; vegetarians consume 124% of the RDA vs. 383% in omnivores. Serum vitamin levels are significantly lower in subjects consuming alternative nutrition with deficiency observed in 24% of vegetarians, 78% of vegans vs. 0% in omnivores. Serum folate levels are within the reference range in all groups. Mild hyperhomocysteinemia in the groups consuming alternative diet is a consequence of vitamin B12 deficiency. Vegetarians and vegans meet the RDA for energy and fat, and have a favourable proportion of saturated, mono- and polyunsaturated fatty acids on total energy intake; the ratio of linoleic/alpha-linolenic acid in their diet corresponds with the recommendations. They have low cholesterol consumption and higher vitamin E and C intake. Optimal fat intake of correct composition is reflected in lower values of atherosclerosis risk factors (cholesterol, LDL-cholesterol, atherogenic index, saturated fatty acids, triacylglycerols), and significantly higher levels of protective substances (linoleic acid, alpha-linolenic acid, HDL-cholesterol, vitamin E, vitamin E/cholesterol, vitamin C). Low lipid risk factors but higher findings of mild hyperhomocysteinemia in vegetarians mean a diminished protective effect of alternative nutrition in cardiovascular disease prevention. PMID:11218148

  16. Reintroduction of a Homocysteine Level-Associated Allele into East Asians by Neanderthal Introgression.

    PubMed

    Hu, Ya; Ding, Qiliang; He, Yungang; Xu, Shuhua; Jin, Li

    2015-12-01

    In this study, we present an analysis of Neanderthal introgression at the dipeptidase 1 gene, DPEP1. A Neanderthal origin for the putative introgressive haplotypes was demonstrated using an established three-step approach. This introgression was under positive natural selection, reached a frequency of >50%, and introduced a homocysteine level- and pigmentation-associated allele (rs460879-T) into East Asians. However, the same allele was also found in non-East Asians, but not from Neanderthal introgression. It is likely that rs460879-T was lost in East Asians and was reintroduced subsequently through Neanderthal introgression. Our findings suggest that Neanderthal introgression could reintroduce an important previously existing allele into populations where the allele had been lost. This study sheds new light on understanding the contribution of Neanderthal introgression to the adaptation of non-Africans. PMID:26392408

  17. Reduction of plasma lipid and homocysteine levels by pyridoxine, folate, cobalamin, choline, riboflavin, and troxerutin in atherosclerosis.

    PubMed

    Olszewski, A J; Szostak, W B; Bialkowska, M; Rudnicki, S; McCully, K S

    1989-01-01

    Elevated plasma homocysteine and lipid levels are risk factors for atherosclerosis. The plasma levels of homocysteine, determined in acid hydrolyzates of plasma, were found to be correlated with total cholesterol (r = 0.47, P less than 0.001), triglycerides (r = 0.40, P less than 0.01), and body mass index (r = 0.42, P less than 0.01) in 52 males, aged 30-60. A group of 12 male survivors of acute myocardial infarction was given pyridoxine, folate, cobalamin, choline, riboflavin, and troxerutin for 21 days. The plasma concentrations of homocysteine and alpha-amino adipic acid declined to 68% (P less than 0.001) and 57% (P less than 0.001) of the pretreatment values, and the cholesterol, triglycerides, and LDL apo B declined to 79% (P less than 0.001), 68% (P less than 0.01), and 63% (P less than 0.001) of the pretreatment values, respectively. The results suggest a new strategy for control of the metabolic abnormalities in atherosclerosis through the use of naturally occurring, non-toxic nutrients which minimize homocysteine accumulation.

  18. Social connectedness is associated with fibrinogen level in a human social network.

    PubMed

    Kim, David A; Benjamin, Emelia J; Fowler, James H; Christakis, Nicholas A

    2016-08-31

    Socially isolated individuals face elevated rates of illness and death. Conventional measures of social connectedness reflect an individual's perceived network and can be subject to bias and variation in reporting. In this study of a large human social network, we find that greater indegree, a sociocentric measure of friendship and familial ties identified by a subject's social connections rather than by the subject, predicts significantly lower concentrations of fibrinogen (a biomarker of inflammation and cardiac risk), after adjusting for demographics, education, medical history and known predictors of cardiac risk. The association between fibrinogen and social isolation, as measured by low indegree, is comparable to the effect of smoking, and greater than that of low education, a conventional measure of socioeconomic disadvantage. By contrast, outdegree, which reflects an individual's perceived connectedness, displays a significantly weaker association with fibrinogen concentrations. PMID:27559060

  19. Zinc and homocysteine levels in polycystic ovarian syndrome patients with insulin resistance.

    PubMed

    Guler, Ismail; Himmetoglu, Ozdemir; Turp, Ahmet; Erdem, Ahmet; Erdem, Mehmet; Onan, M Anıl; Taskiran, Cagatay; Taslipinar, Mine Yavuz; Guner, Haldun

    2014-06-01

    In this study, our objective was to evaluating the value of serum zinc levels as an etiologic and prognostic marker in patients with polycystic ovarian syndrome. We conducted a prospective study, including 53 women with polycystic ovarian syndrome and 33 healthy controls. We compared serum zinc levels, as well as clinical and metabolic features, of the cases. We also compared serum zinc levels between patients with polycystic ovarian syndrome with insulin resistance. Mean zinc levels were found to be significantly lower in patients with polycystic ovarian syndrome than healthy controls. Multiple logistic regression analysis of significant metabolic variables between polycystic ovarian syndrome and control groups (serum zinc level, body mass index, the ratio of triglyceride/high-density lipoprotein cholesterol, and homocysteine) revealed that zinc level was the most significant variable to predict polycystic ovarian syndrome. Mean serum zinc levels tended to be lower in patients with polycystic ovarian syndrome with impaired glucose tolerance than patients with normal glucose tolerance, but the difference was not statistically significant. In conclusion, zinc deficiency may play a role in the pathogenesis of polycystic ovarian syndrome and may be related with its long-term metabolic complications.

  20. Plasmatic higher levels of homocysteine in Non-alcoholic fatty liver disease (NAFLD)

    PubMed Central

    2013-01-01

    Background Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease, which includes a spectrum of hepatic pathology such as simple steatosis, steatohepatitis, fibrosis and cirrhosis. The increased serum levels of homocysteine (Hcy) may be associated with hepatic fat accumulation. Genetic mutations in the folate route may only mildly impair Hcy metabolism. The aim of this study was to investigate the relation between liver steatosis with plasma homocysteine level and MTHFR C677T and A1298C polymorphisms in Brazilian patients with NAFLD. Methods Thirty-five patients diagnosed with NAFLD by liver biopsy and forty-five healthy controls neither age nor sex matched were genotyped for C677T and A1298C MTHFR polymorphisms using PCR-RFLP and PCR-ASA, respectively, and Hcy was determined by HPLC. All patients were negative for markers of Wilson’s, hemochromatosis and autoimmune diseases. Their daily alcohol intake was less than 100 g/week. A set of metabolic and serum lipid markers were also measured at the time of liver biopsies. Results The plasma Hcy level was higher in NAFLD patients compared to the control group (p = 0.0341). No statistical difference for genotypes 677C/T (p = 0.110) and 1298A/C (p = 0.343) in patients with NAFLD and control subjects was observed. The genotypes distribution was in Hardy-Weinberg equilibrium (677C/T p = 0.694 and 1298 A/C p = 0.188). The group of patients and controls showed a statistically significant difference (p < 0.001) for BMI and HOMA_IR, similarly to HDL cholesterol levels (p < 0,006), AST, ALT, γGT, AP and triglycerides levels (p < 0.001). A negative correlation was observed between levels of vitamin B12 and Hcy concentration (p = 0.005). Conclusion Our results indicate that plasma Hcy was higher in NAFLD than controls. The MTHFR C677T and A1298C polymorphisms did not differ significantly between groups, despite the 677TT homozygous frequency was higher in patients (17

  1. Electrocardiogram Derived QRS Duration >120 ms is Associated With Elevated Plasma Homocysteine Levels in a Rural Australian Cross-Sectional Population

    PubMed Central

    Leng, Yvonne Lee Yin; Zhou, Yuling; Ke, Honghong; Jelinek, Herbert; McCabe, Joel; Assareh, Hassan; McLachlan, Craig S.

    2015-01-01

    Abstract Homocysteine levels in the low to moderate range for cardiovascular risk have been previously associated with left ventricular cardiac hypertrophy (LVH). Electrocardiogram (ECG) derived QRS duration has also been used as an epidemiological screening marker for cardiac hypertrophy risk. QRS duration cut offs have not been previously modeled to assess homocysteine levels in community populations. Our aims are to determine if QRS duration is associated with an elevated homocysteine level in a cross-sectional Australian aging rural population. A retrospective study design utilizing a rural health diabetic screening clinic database containing observational data from the period January 9, 2002 till September 25, 2012. One hundred seventy-eight individuals (>21 years of age) from the database were included in the study. Inclusion criteria included being nondiabetic and having both a QRS duration measure and a matching homocysteine level within the same subject. All participants were from the Albury-Wodonga area, with a mean age of >64 years for both sexes. Mean population homocysteine plasma levels were 10.4 μmol/L (SD = 3.6). The mean QRS duration was 101.8 ms (SD = 17.4). Groups were stratified on the basis of QRS duration (≤120 ms [n = 157] and >120 ms [n = 21]). QRS duration subgroup (≤120 ms vs >120 ms) mean differences across homocysteine levels were 10.1 μmol/L (SD = 3.3) and 12.2 μmol/L (SD = 4.7), respectively (P = 0.016). Other ECG parameters (PQ interval, QTc interval, and QT dispersion) measurements were not significantly associated with differences in plasma homocysteine (P = not significant). We conclude that in community populations homocysteine may be moderately elevated when QRS durations are >120 ms. Small additional increases in homocysteine levels may suggest a risk factor for ECG diagnosis of LVH. PMID:26166085

  2. Evaluation of homocysteine levels in individuals having nonsyndromic cleft lip with or without palate

    PubMed Central

    Abdulla, Riaz; Tellis, Rouchelle Charmaine; Athikari, Roshan; Kudkuli, Jagadish

    2016-01-01

    Context: Nonsyndromic cleft lip with or without palate (NSCL ± P) is a genetic predisposition involving defects in shape and makeup of the lip and palate. Elevation of homocysteine (Hcy) levels is seen in medical complications such as developmental anomalies causing neural tube defects, congenital vascular diseases, neurodegenerative and psychiatric conditions. Evaluation of serum Hcy levels forms an important feature to look further into molecular aspects. Aims: The aim of this study was to evaluate the Hcy levels in NSCL ± P cases by comparing with control cases having no orofacial deformities. Settings and Design: This study was performed with a biochemical assay in a research laboratory. Materials and Methods: A cross-sectional prevalence study was done to compare the concentrations of Hcy between 25 NSCL ± P patients and 15 healthy controls. Blood samples were collected from both the patients and controls and assessed for serum Hcy level using competent chemiluminescent immunoassay technique. Statistical Analysis Used: Student's t-test was used for statistical analysis. Results: The average Hcy concentration was 9.5 μmol/L in control group. There was an increase in Hcy concentration among the NSCL ± P cases with an average value of 18.4 μmol/L. The results were found to be statistically significant using Student's t-test. Conclusions: The results of this study indicate that Hcy concentration has a significant elevation in NSCL ± P patients when compared with that of control cases. PMID:27721602

  3. Homocysteine levels in patients with primary and secondary Raynaud's phenomenon. Its association with microangiopathy severity.

    PubMed

    Vayá, Amparo; Sánchez, Fernando; Todolí, Jose; Calvo, Javier; Alis, Rafael; Collado, Susana; Ricart, Jose M

    2014-01-01

    The association between hyperhomocysteinemia (HHcy) and Raynaud's phenomenon (RP) remains a matter of debate. In 18 primary RP, 23 secondary RP and 41 controls, we investigated homocysteine (Hcy) levels along with biochemical and inflammatory parameters. The Hcy levels in both primary and secondary RP were elevated when compared with controls (p < 0.05 and p < 0.01, respectively). As age was higher in secondary RP as compared with controls (p < 0.01), both primary and secondary RP were age-matched with a corresponding control group, and with Hcy maintaining its statistical significance (p < 0.05). No differences in creatinine, B12 vitamin or folic acid were observed between groups (p > 0.05), or in the prevalence of cardiovascular risk factors (p > 0.05). When patients were classified according to presence or absence of digital ulcers, as a sign of microangiopathy severity, the former showed higher Hcy levels than the latter (p = 0.035). Our results indicate that both primary and secondary RP patients show a mild increase in Hcy levels, which is not related to age, vitamin deficiencies or impaired renal function, but is related to microangiopathy severity. Therefore the association of HHcy and RP suggest that Hcy may contribute to endothelial dysregulation, which characterizes this disease. Specific studies should be designed to elucidate the pathogenesis of HHcy in these patients.

  4. Preoperative neutrophil–lymphocyte ratio and fibrinogen level in patients distinguish between muscle-invasive bladder cancer and non-muscle-invasive bladder cancer

    PubMed Central

    Ma, Chengquan; Lu, Bingxin; Diao, Chengwen; Zhao, Kun; Wang, Xinpeng; Ma, Baojing; Lu, Baojian; Sun, Erlin

    2016-01-01

    Introduction The aim of this study was to explore if the preoperative neutrophil–lymphocyte ratio (NLR) and fibrinogen level can help in distinguishing between muscle-invasive bladder cancer (MIBC) and non-muscle-invasive bladder cancer (NMIBC). Methods We identified 669 patients who underwent surgery at our institution, and evaluated their preoperative NLRs and fibrinogen levels. Patients were divided into two groups, NMIBC (group-I) and MIBC (group-II), according to the postoperative pathology. For the intergroup comparison, data obtained from the two groups were evaluated using independent samples t-test. The cutoff value of the NLR, fibrinogen level, and integrated NLR and fibrinogen level was determined with receiver operating characteristic (ROC) curve. Results The mean NLRs of group-I and group-II were found as 2.71±2.46 and 4.66±8.00, respectively (P<0.001). The fibrinogen levels of the two groups were ~3.13±0.70 g/L and 3.41±0.84 g/L, respectively (P=0.001). Whether the NLR, fibrinogen level, and integrated NLR and fibrinogen level can help in distinguishing between MIBC and NMIBC was evaluated with ROC curve. The cutoff value of NLR was estimated as 2.01 according to the Youden index. With this value, sensitivity was found as 67.1%, specificity was 52.7%, and area under receiver operating characteristic (ROC) curve (AUC) was 0.601 (P=0.031). The cutoff value of fibrinogen level was estimated as 3.17 g/L according to the Youden index. Accordingly, sensitivity was found as 58%, specificity was 58%, and AUC was 0.60 (P=0.001). The cutoff value of integrated NLR and fibrinogen level was found as 0.166; the sensitivity was found as 86%, specificity was 42%, and AUC was 0.801 (P=0.01). Conclusion The data obtained in this study suggested that 67.1% of Ta-T1 tumors were likely to be invasive if the NLR was >2.01 and 58% were likely to be invasive if the fibrinogen level was >3.17 g/L. When we used both the NLR and fibrinogen level to distinguish between

  5. Association between High Serum Homocysteine Levels and Biochemical Characteristics in Women with Polycystic Ovarian Syndrome: A Systematic Review and Meta-Analysis

    PubMed Central

    Peng, Zheng; Liu, Xuexiang; Sun, Yifan; Dai, Shengming

    2016-01-01

    Background Elevated homocysteine levels have been observed in previous studies of PCOS; however, the nature of the associations between high homocysteine levels and the biochemical characteristics of polycystic ovarian syndrome (PCOS)—such as obesity, insulin resistance (IR), and androgen levels—is still uncertain. Methods A systematic search was conducted electronically up to December 28, 2015 using specific eligibility criteria. Standardized mean difference (SMD) and the corresponding 95% confidence intervals (95% CIs) were used as a measure of effect size. Results A total of 34 studies (with 1,718 cases and 1,399 controls) of homocysteine levels in PCOS were pooled in this meta-analysis. Significantly lower homocysteine levels were found in controls than in PCOS patients (SMD = 0.895, 95% CI = 0.643–1.146, P<0.001; I2 = 90.4% and P<0.001 for heterogeneity), regardless of the degree of obesity, IR, or androgen levels. Homocysteine levels in non-IR PCOS patients were significantly lower than those of PCOS patients with IR (SMD = 0.69, 95% CI = 0.37–1.01, P<0.01; I2 = 0% and P = 0.50 for heterogeneity). However, metformin treatment did not appear to cause any significant change in the homocysteine levels of PCOS patients (SMD = –0.17, 95% CI = –1.10–0.75, P = 0.71; I2 = 92% and P<0.01 for heterogeneity). Conclusions High homocysteine levels in women with PCOS are not related to degree of obesity, IR, or androgen levels. Metformin treatment cannot decrease the homocysteine levels in PCOS patients. PMID:27281026

  6. Homocysteine levels in schizophrenia and affective disorders—focus on cognition

    PubMed Central

    Moustafa, Ahmed A.; Hewedi, Doaa H.; Eissa, Abeer M.; Frydecka, Dorota; Misiak, Błażej

    2014-01-01

    Although homocysteine (Hcy) has been widely implicated in the etiology of various physical health impairments, especially cardiovascular diseases, overwhelming evidence indicates that Hcy is also involved in the pathophysiology of schizophrenia and affective disorders. There are several mechanisms linking Hcy to biological underpinnings of psychiatric disorders. It has been found that Hcy interacts with NMDA receptors, initiates oxidative stress, induces apoptosis, triggers mitochondrial dysfunction and leads to vascular damage. Elevated Hcy levels might also contribute to cognitive impairment that is widely observed among patients with affective disorders and schizophrenia. Supplementation of vitamins B and folic acid has been proved to be effective in lowering Hcy levels. There are also studies showing that this supplementation strategy might be beneficial for schizophrenia patients with respect to alleviating negative symptoms. However, there are no studies addressing the influence of add-on therapies with folate and vitamins B on cognitive performance of patients with schizophrenia and affective disorders. In this article, we provide an overview of Hcy metabolism in psychiatric disorders focusing on cognitive correlates and indicating future directions and perspectives. PMID:25339876

  7. Higher Fibrinogen Level is Independently Linked with the Presence and Severity of New-Onset Coronary Atherosclerosis among Han Chinese Population

    PubMed Central

    Zhang, Yan; Zhu, Cheng-Gang; Guo, Yuan-Lin; Xu, Rui-Xia; Li, Sha; Dong, Qian; Li, Jian-Jun

    2014-01-01

    Background Fibrinogen is a coagulation/inflammatory biomarker strongly associated with atherogenesis. However, no data is currently available regarding the association of fibrinogen level with the presence and severity of new-onset coronary atherosclerosis assessed by Gensini score (GS), particularly in Han Chinese with a large sample size. Methods and Results We studied 2288 consecutive, new-onset subjects undergoing coronary angiography with angina-like chest pain. Clinical and laboratory data were collected. Coronary stenotic lesions were considered to be the incidence of coronary atherosclerosis. The severity of coronary stenosis was determined by the GS system. Data indicated that patients with high GS had significantly elevated fibrinogen level (p<0.001). The prevalence and severity of coronary atherosclerosis were dramatically increased according to fibrinogen tertiles. Spearman correlation analysis revealed a positive association between fibrinogen level and GS (r = 0.138, p<0.001). Multivariate logistic regression analysis demonstrated that plasma fibrinogen level was independently associated with high GS (OR = 1.275, 95% CI 1.082–1.502, p = 0.004) after adjusting for potential confounders. Moreover, fibrinogen level was also independently related to the presence of coronary atherosclerosis (fibrinogen tertile 2: OR = 1.192, 95% CI 0.889–1.598, p = 0.241; tertile 3: OR = 2.003, 95% CI 1.383–2.903, p <0.001) and high GS (fibrinogen tertile 2: OR = 1.079, 95% CI 0.833–1.397, p = 0.565; tertile 3: OR = 1.524, 95% CI 1.155–2.011, p = 0.003) in a dose-dependent manner. Receiver-operating characteristic curve analysis showed that the best fibrinogen cut-off value for predicting the severity of coronary stenosis was 3.21 g/L. Conclusions Higher fibrinogen level is independently linked with the presence and severity of new-onset coronary atherosclerosis in Han Chinese population. PMID:25426943

  8. Effect of Folic Acid, Betaine, Vitamin B6, and Vitamin B12 on Homocysteine and Dimethylglycine Levels in Middle-Aged Men Drinking White Wine

    PubMed Central

    Rajdl, Daniel; Racek, Jaroslav; Trefil, Ladislav; Stehlik, Pavel; Dobra, Jana; Babuska, Vaclav

    2016-01-01

    Moderate regular consumption of alcoholic beverages is believed to protect against atherosclerosis but can also increase homocysteine or dimethylglycine, which are putative risk factors for atherosclerosis. We aimed (1) to investigate the effect of alcohol consumption on vitamins and several metabolites involved in one-carbon metabolism; and (2) to find the most effective way of decreasing homocysteine during moderate alcohol consumption. Methods: Male volunteers (n = 117) were randomly divided into five groups: the wine-only group (control, 375 mL of white wine daily for one month) and four groups combining wine consumption with one of the supplemented substances (folic acid, betaine, and vitamins B12 or B6). Significant lowering of homocysteine concentration after the drinking period was found in subjects with concurrent folate and betaine supplementation. Vitamin B12 and vitamin B6 supplementation did not lead to a statistically significant change in homocysteine. According to a multiple linear regression model, the homocysteine change in the wine-only group was mainly determined by the interaction between the higher baseline homocysteine concentration and the change in dimethylglycine levels. Folate and betaine can attenuate possible adverse effects of moderate alcohol consumption. Dimethylglycine should be interpreted together with data on alcohol consumption and homocysteine concentration. PMID:26771632

  9. Hepatic fibrinogen storage disease due to the fibrinogen γ375 Arg → Trp mutation "fibrinogen Aguadilla" is present in Arabs.

    PubMed

    Al-Hussaini, Abdulrahman; Altalhi, Abdulhadi; El Hag, Imad; AlHussaini, Hussa; Francalanci, Paola; Giovannoni, Isabella; Callea, Francesco

    2014-01-01

    The mutation γ375Arg → Trp (fibrinogen Aguadilla) is one of four mutations (Brescia, Aguadilla, Angers, and AI duPont) capable of causing hepatic storage of fibrinogen. It has been observed in four children from the Caribbean, Europe, and Japan, suffering from cryptogenic liver disease. We report the first case of hepatic fibrinogen storage disease in Arabs due to a mutation in the fibrinogen γ-chain gene in a 3-year-old Syrian girl presenting with elevated liver enzymes. The finding of an impressive accumulation of fibrinogen in liver cells raised the suspicion of endoplasmic reticulum storage disease. Sequencing of the fibrinogen genes revealed a γ375Arg → Trp mutation (fibrinogen Aguadilla) in the child and in her father. In conclusion, when confronted with chronic hepatitis of unknown origin, one should check the plasma fibrinogen level and look carefully for the presence of hepatocellular intracytoplasmic globular inclusions to exclude hepatic fibrinogen storage disease.

  10. Distribution and determinants of plasma homocysteine levels in rural Chinese twins across the lifespan.

    PubMed

    Ji, Yuelong; Kong, Xiangyi; Wang, Guoying; Hong, Xiumei; Xu, Xin; Chen, Zhu; Bartell, Tami; Xu, Xiping; Tang, Genfu; Hou, Fanfan; Huo, Yong; Wang, Xiaobin; Wang, Binyan

    2014-12-01

    Plasma homocysteine (Hcy) is a modifiable, independent risk factor for cardiovascular disease (CVD) and is affected by both environmental and genetic factors. This study aimed to describe the gender- and age-specific distribution of Hcy concentration for 1117 subjects aged 10-66 years, a subset of a community-based rural Chinese twin cohort. In addition, we examined environmental and genetic contributions to variances in Hcy concentration by gender and age groups. We found that the distribution pattern for Hcy varied by both age and gender. Males had higher Hcy than females across all ages. Elevated Hcy was found in 43% of male adults and 13% of female adults. Moreover, nearly one fifth of children had elevated Hcy. Genetic factors could explain 52%, 36% and 69% of the variation in Hcy concentration among children, male adults and female adults, respectively. The MTHFR C677T variant was significantly associated with Hcy concentrations. Smokers with the TT genotype had the highest Hcy levels. Overall, our results indicate that elevated Hcy is prevalent in the children and adults in this rural Chinese population. The early identification of elevated Hcy will offer a window of opportunity for the primary prevention of CVD and metabolic syndrome. PMID:25529062

  11. Effects of folic acid supplementation on serum homocysteine and lipoprotein (a) levels during pregnancy

    PubMed Central

    Hekmati Azar Mehrabani, Zohreh; Ghorbanihaghjo, Amir; Sayyah Melli, Manizheh; Hamzeh-Mivehroud, Maryam; Fathi Maroufi, Nazila; Bargahi, Nasrin; Bannazadeh Amirkhiz, Maryam; Rashtchizadeh, Nadereh

    2015-01-01

    Introduction:There are many ideas concerning the etiology and pathogenesis of preeclampsia including endothelial dysfunction, inflammation and angiogenesis. Elevated levels of total homocysteine (Hcy) and lipoprotein (a) [Lp(a)] are risk factors for endothelial dysfunction. This study aimed to evaluate the effect of high dose folic acid (FA) on serum Hcy and Lp(a) concentrations with respect to methylenetetrahydrofolate reductase (MTHFR) polymorphisms 677C→T during pregnancy. Methods: In a prospective uncontrolled intervention, 90 pregnant women received 5 mg FA supplementation before pregnancy till 36th week of pregnancy. The MTHFR polymorphisms 677C→T, serum lactate dehydrogenase activity, urine protein and creatinine concentrations were measured before starting folic acid administration. Serum levels of Hcy and Lp(a) were determined before and after completion of folic acid supplementation period. Results: Supplementation of the patients with FA for 36 week decreased the median (minimum– maximum) levels of serum Hcy from 11.40 μmol/L (4.40-28.70) to 9.70 (1.60-20.80) μmol/L (p=0.001). There was no significant change in serum Lp(a) after FA supplementation (p=0.17). The overall prevalence of genotypes in pregnant women that were under study for MTHFR C677T polymorphism was 53.3% CC, 26.7% CT and 20.0% TT. There was no correlation between decreasing level of serum Hcy in the patients receiving FA and MTHFR polymorphisms. Conclusion:Although FA supplementation decreased serum levels of Hcy in different MTHFR genotypes, serum Lp(a) was not changed by FA supplements. Our data suggests that FA supplementation effects on serum Hcy is MTHFR genotype independent in pregnant women. PMID:26929921

  12. Evaluation of Serum Homocysteine and Leptin Levels in Patients with Uveitis

    PubMed Central

    Elbay, Arif Emre; Topalkara, Ayşen; Elbay, Ahmet; Erdoğan, Haydar; Vural, Ayşe; Bahadır Çetin, Abdi

    2015-01-01

    Objectives: To evaluate the serum homocysteine (Hcy) and leptin levels in patients with uveitis. Ma­te­ri­als and Met­hods: The 70 cases included in the study comprised 3 groups: patients with Behçet’s uveitis (BU), patients with non-Behçet’s uveitis (NBU) and healthy controls. Body mass index was calculated for each subject. Serum Hcy and leptin levels were measured. Furthermore, acute-phase reactants including erythrocyte sedimentation rate (ESR), C-reactive protein and neutrophil count were measured. Re­sults: Serum Hcy levels were 15.04±4.59 µmol/L in the BU group, 15.4±6.87 µmol/L in the NBU group and 13.64±4.72 µmol/L in the control group (p>0.05). The serum leptin levels of male patients in the BU group, NBU group and control group were 4.76±3.54 ng/ml, 6.33±3.74 ng/ml and 5.47±6.33 ng/ml, respectively (p>0.05). When we compared serum leptin levels in female patients and controls, the mean serum leptin concentrations were significantly higher in female BU and NBU patients (24.83±17.62 ng/ml and 28.46±13.90 ng/ml, respectively) than in healthy control volunteers (9.62±6.36 ng/ml, p<0.05). In addition, the ESR value differences between groups were statistically significant (p<0.05). Conclusion: A larger case series is necessary to investigate serum Hcy and leptin concentrations in uveitis patients. PMID:27800222

  13. Fatty acid status and its relationship to cognitive decline and homocysteine levels in the elderly.

    PubMed

    Baierle, Marília; Vencato, Patrícia H; Oldenburg, Luiza; Bordignon, Suelen; Zibetti, Murilo; Trentini, Clarissa M; Duarte, Marta M M F; Veit, Juliana C; Somacal, Sabrina; Emanuelli, Tatiana; Grune, Tilman; Breusing, Nicolle; Garcia, Solange C

    2014-09-01

    Polyunsaturated fatty acids (PUFAs), especially the n-3 series, are known for their protective effects. Considering that cardiovascular diseases are risk factors for dementia, which is common at aging, the aim of this study was to evaluate whether fatty acid status in the elderly was associated with cognitive function and cardiovascular risk. Forty-five elderly persons (age ≥ 60 years) were included and divided into two groups based on their Mini-Mental Status Examination score adjusted for educational level: the case group (n = 12) and the control group (n = 33). Serum fatty acid composition, homocysteine (Hcy), hs-CRP, lipid profile and different cognitive domains were evaluated. The case group, characterized by reduced cognitive performance, showed higher levels of 14:0, 16:0, 16:1n-7 fatty acids and lower levels of 22:0, 24:1n-9, 22:6n-3 (DHA) and total PUFAs compared to the control group (p < 0.05). The n-6/n-3 ratio was elevated in both study groups, whereas alterations in Hcy, hs-CRP and lipid profile were observed in the case group. Cognitive function was positively associated with the 24:1n-9, DHA and total n-3 PUFAs, while 14:0, 16:0 and 16:1n-7 fatty acids, the n-6/n-3 ratio and Hcy were inversely associated. In addition, n-3 PUFAs, particularly DHA, were inversely associated with cardiovascular risk, assessed by Hcy levels in the elderly. PMID:25221976

  14. C677T methylenetetrahydrofolate reductase and plasma homocysteine levels among Thai vegans and omnivores.

    PubMed

    Kajanachumpol, Saowanee; Atamasirikul, Kalayanee; Tantibhedhyangkul, Phieuvit

    2013-01-01

    Hyperhomocysteinemia among vegetarians and vegans is caused mostly by vitamin B12 deficiency. A C-to-T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene results in a thermolabile MTHFR, which may affect homocysteine (Hcy) levels. The importance of this gene mutation among populations depends on the T allele frequency. Blood Hcy, vitamin B12, folate, vitamin B6, and MTHFR C677T mutation status were determined in 109 vegans and 86 omnivores aged 30 - 50 years. The vegans had significantly higher Hcy levels than the omnivores, geometric means (95 % CI) 19.2 (17.0 - 21.7) µmol/L vs. 8.53 (8.12 - 8.95) µmol/L, p < 0.001. A C-to-T mutation in the vegans increased plasma Hcy, albeit insignificantly; geometric means 18.2 µmol/L, 20.4 µmol/L, and 30.0 µmol/L respectively in CC, CT, and TT MTHFR genotypes. There was also a significant decrease in serum folate; geometric means 12.1 ng/mL, 9.33 ng/mL, and 7.20 ng/mL respectively, in the CC, CT, and TT mutants, p = 0.006, and particularly, in the TT mutant compared with the CC wild type, 7.20 ng/mL vs. 12.1 ng/mL, p = 0.023. These findings were not seen in the omnivores. It was concluded that hyperhomocysteinemia is prevalent among Thai vegans due to vitamin B12 deficiency. C-to-T MTHFR mutation contributes only modestly to the hyperhomocysteinemia.

  15. The homocysteine controversy.

    PubMed

    Smulders, Yvo M; Blom, Henk J

    2011-02-01

    Mild to moderate hyperhomocysteinemia has been identified as a strong predictor of cardiovascular disease, independent from classical atherothrombotic risk factors. In the last decade, a number of large intervention trials using B vitamins have been performed and have shown no benefit of homocysteine-lowering therapy in high-risk patients. In addition, Mendelian randomization studies failed to convincingly demonstrate that a genetic polymorphism commonly associated with higher homocysteine levels (methylenetetrahydrofolate reductase 677 C>T) is a risk factor for cardiovascular disease. Together, these findings have cast doubt on the role of homocysteine in cardiovascular disease pathogenesis, and the homocysteine hypothesis has turned into a homocysteine controversy. In this review, we attempt to find solutions to this controversy. First, we explain that the Mendelian randomization analyses have limitations that preclude final conclusions. Second, several characteristics of intervention trials limit interpretation and generalizability of their results. Finally, the possibility that homocysteine lowering is in itself beneficial but is offset by adverse side effects of B vitamins on atherosclerosis deserves serious attention. As we explain, such side effects may relate to direct adverse effects of the B-vitamin regimen (in particular, the use of high-dose folic acid) or to proinflammatory and proproliferative effects of B vitamins on advanced atherosclerotic lesions.

  16. Secondary palatal closure in rats in association with relative maternofetal levels of folic acid, vitamin B12, and homocysteine.

    PubMed

    Weingärtner, Jens; Maile, Sergei; Proff, Peter; Reicheneder, Claudia; Bienengräber, Volker; Fanghänel, Jochen; Gedrange, Tomas

    2007-01-01

    Animal experiments are used in embryological and teratological studies of matters relevant to humans. In gravid rats, a decrease in the levels of folic acid and vitamin B12 was observed in maternal blood and in amniotic fluid. At the time of secondary palatal closure (14th day of pregnancy), the folic acid level of the amniotic fluid was 73% lower than that of the maternal blood. A drop in vitamin B12 in conjunction with an increase in amniotic homocysteine levels is seen as a risk factor for malformation of the palate. The understanding of causes of cleft generation could lead to a prophylactic treatment approach.

  17. Smoking, fibrinogen and cancer mortality.

    PubMed Central

    Everett, Charles J.; Wells, Brian J.; Frithsen, Ivar L.; Koopman, Richelle J.

    2007-01-01

    Associations of race, smoking history and fibrinogen levels with cancer mortality were investigated prospectively using the ARIC study. Our cohort consisted of 14,320 participants aged 45-64 at baseline. In an adjusted Cox regression, black current heavy smokers (> or = 15 cigarettes per day) demonstrated higher risk of respiratory/intrathoracic organ cancer mortality than nonblack current heavy smokers. Black former heavy smokers were also found to be at an increased risk of respiratory/intrathoracic organ cancer mortality when compared to nonblack former heavy smokers. Elevated fibrinogen levels were associated with an increased risk of respiratory/intrathoracic organ cancer mortality. Compared to fibrinogen < 259 mg/dl, fibrinogen 294-335 mg/dl had an adjusted hazard ratio of 3.68 (95% CI: 1.80-7.55), and fibrinogen > or = 336 mg/dl had an adjusted hazard ratio of 3.78 (95% CI: 1.84-7.75). Fibrinogen was also a predictor of other types of cancer mortality among black participants, but not among nonblack participants. For 10 race/smoking history categories, fibrinogen levels ranged from a mean of 287 mg/dl for nonblack former light smokers to a mean of 338 mg/dl for black current heavy smokers. Smokers had higher fibrinogen levels than nonsmokers, and black smokers had higher fibrinogen levels than nonblack smokers. Smoking carries high risks of cancer mortality for African Americans. A factor that needs to be considered in the overall assessment of risk is fibrinogen level, which has been linked to angiogenesis and metastases of tumors. PMID:17444421

  18. Effect Of G2706A and G1051A polymorphisms of the ABCA1 gene on the lipid, oxidative stress and homocystein levels in Turkish patients with polycystıc ovary syndrome

    PubMed Central

    2011-01-01

    Background Obesity, insulin resistance and hyperandrogenism, crucial parameters of Polycystic ovary syndrome (PCOS) play significant pathophysiological roles in lipidemic aberrations associated within the syndrome. Parts of the metabolic syndrome (low HDL and insulin resistance) appeared to facilitate the association between PCOS and coronary artery disease, independently of obesity. ABCA1 gene polymorphism may be altered this components in PCOS patients. In this study, we studied 98 PCOS patients and 93 healthy controls. All subjects underwent venous blood drawing for complete hormonal assays, lipid profile, glucose, insulin, malondialdehyde, nitric oxide, disulfide levels and ABCA genetic study. Results In PCOS group fasting glucose, DHEAS, 17-OHP, free testosterone, total-cholesterol, triglyceride, LDL-cholesterol and fibrinogen were significantly different compare to controls. The genotype ABCA G2706A distribution differed between the control group (GG 60.7%, GA 32.1%, AA 7.1%) and the PCOS patients (GG 8.7%, GA 8.7%, AA 76.8%). The frequency of the A allele (ABCAG2706A) was higher in PCOS patients than control group with 13,0% and 23,2%, respectively. In this study, the homocystein and insulin levels were significantly higher in PCOS patients with ABCA G1051A mutant genotype than those with heterozygote and wild genotypes. Conclusions We found higher percentage of AA genotype and A allele of ABCA G2706A in PCOS patients compare to controls. The fasting insulin and homocystein levels were significantly higher in PCOS patients with ABCA G1051A mutant genotype than those with heterozygote and wild genotypes. PMID:22035022

  19. Plasma homocysteine level is a risk factor for osteoporotic fractures in elderly patients

    PubMed Central

    Zhu, Yuefeng; Shen, Jie; Cheng, Qun; Fan, Yongqian; Lin, Weilong

    2016-01-01

    Objective To study the relationship of plasma homocysteine (Hcy), bone turnover biomarkers (BTB), and bone mineral density (BMD) with osteoporotic fracture (OPF) in elderly people. Methods Eighty-two patients (aged 65 years or older) admitted to our orthopedics department between October 2014 and May 2015 were randomly divided into three groups: 1) OPF group: 39 cases with the mean age 81.82±5.49 years, which included 24 females and 15 males; 2) high-energy fracture (HEF) group: 22 cases with the mean age 78.88±5.75 years, which included 16 females and six males; 3) non-bone-fracture group: 21 cases with mean age 79.75±5.47 years without bone fracture, which included 14 females and seven males. Plasma Hcy, BTB, and BMD were measured. Analysis of variance and multiple regression analysis were used in the statistical analysis. Results There was no significant difference in either age or sex among the three groups. There were significant differences in plasma Hcy and hip BMD between the OPF and HEF groups; there was also significant difference in plasma Hcy, 25-(OH) Vit D, and hip BMD between the OPF and non-fracture groups. There was no difference in lumbar spine BMD between the OPF group and the other two groups. There was no significant difference in plasma Hcy, 25-(OH) Vit D, hip or lumbar spine BMD between the HEF and non-fracture group. There was no significant difference in procollagen type I N-propeptide of type I collagen, serum C-terminal cross-linking telopeptide of type I collagen, and parathyroid hormone among the three groups. Plasma Hcy was linearly correlated with age and serum C-terminal cross-linking telopeptide of type I collagen, but not correlated with either hip or lumbar spine BMD or any other BTBs. Conclusion In this study, we found that the plasma Hcy level in elderly patients with OPF is higher than that of nonosteoporotic patients. It is not correlated with BMD, but positively correlated with bone resorption markers. An increased Hcy

  20. Plasma homocysteine, methionine and S-adenosylhomocysteine levels following high-dose methotrexate treatment in pediatric patients with acute lymphoblastic leukemia or Burkitt lymphoma: association with hepatotoxicity.

    PubMed

    Kubota, Masaru; Nakata, Rieko; Adachi, Souichi; Watanabe, Ken-Ichiro; Heike, Toshio; Takeshita, Yasufumi; Shima, Midori

    2014-07-01

    This study aimed to investigate: (i) changes of plasma homocysteine, methionine and S-adenosylhomocysteine levels following high-dose methotrexate (HD-MTX) treatment and (ii) the correlation of these sulfur-containing amino acids with MTX-induced hepatotoxicity. Fifteen pediatric patients with acute lymphoblastic leukemia and one patient with Burkitt lymphoma, with a total of 26 treatment courses of HD-MTX, were enrolled. Homocysteine levels increased at 24 h after HD-MTX treatment, and showed marginal decreases at 48 and 72 h. Methionine levels showed a biphasic pattern, i.e. an initial decrease at 24 h followed by increases at 48 and 72 h. S-adenosylhomocysteine exhibited a marginal decrease at 24 h. Changes of homocysteine exhibited significant correlation only with a maximum increase of alanine aminotransferase or total bilirubin from baseline. This study has demonstrated, for the first time, simultaneous changes of plasma homocysteine, methionine and S-adenosylhomocysteine following HD-MTX. The potential of homocysteine as a marker of hepatotoxicity is also presented.

  1. Urinary fibrinogen and renal tubulointerstitial fibrinogen deposition: Discriminating between primary FSGS and minimal change disease.

    PubMed

    Wang, Yu; Zheng, Chunxia; Xu, Feng; Liu, Zhihong

    2016-09-23

    Primary focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD) are common types of primary glomerular disease; they share numerous clinical and pathological similarities but have different treatment regimens and prognoses. It is therefore necessary to distinguish between them and to explore the mechanism underlying their differences. Fibrinogen is reportedly involved in podocyte damage and in renal fibrosis in vitro and in animal models of kidney disease. We thus tested urinary fibrinogen, serum fibrinogen, and renal fibrinogen deposition levels in a cohort comprising 50 patients with FSGS and 40 patients with MCD. Our results suggested that urinary fibrinogen and renal interstitial fibrinogen deposition levels were significantly higher in the FSGS patients than in the MCD patients, while serum fibrinogen levels did not differ between the groups. Receiver operating characteristic (ROC) curve analysis showed an excellent diagnostic ability for urinary fibrinogen and a fair diagnostic ability for tubulointerstitial fibrinogen deposition in differentiating FSGS from MCD. Additionally, we found that urinary fibrinogen levels were positively correlated with the 24-h urine protein levels in patients with FSGS but not in patients with MCD. In conclusion, urinary fibrinogen and renal interstitial fibrinogen deposition is elevated in primary FSGS compared to MCD, which may be relevant to both diagnosis and pathogenesis.

  2. Relationship of serum homocysteine level with nutritional status and HbA1c level in elderly inpatients

    PubMed Central

    Chen, Sheng-Fang; Cui, Chun-Li; Wu, Ping; Xie, Nan-Zi

    2013-01-01

    Background: Hyperhomocysteinemia is a risk factor for vascular diseases. This study aimed to investigate the serum total homocysteine (tHcy) level and nutritional status in elderly inpatients and determine the relationship between tHcy level and nutritional status. Methods: This cross sectional study was carried out in the Tongji hospital, and 142 subjects were consecutively recruited. Fasting blood was collected, and the liver and kidney function, blood glucose, glycosylated hemoglobin (HbA1c), plasma protein, lipid profile, folic acid, vitamin B12 and serum total tHcy were measured. Anthropometric measurements, grip strength and the shortened MNA form (MNA-SF) were used to assess the nutritional status. Results: Undernutrition was common in this population. Based on MNA-SF scores, 34.2% of subjects were at risk of malnutrition, and malnourished subjects accounted for 4.9%. The mean tHcy was 14.10±5.46 μmol/l, and the prevalence of hyperhomocysteinemia was 32.4% (46/142). Hyperhomocysteinemia was a risk factor of cerebral infarction (RR=1.636, 95% CI: 1.169-2.288); Serum tHcy was negatively correlated with serum folic acid, vitamin B12 and MNA-SF score (r=-0.348,P=0.000; r=-0.236, P=0.005; r=-0.208, P=0.014), and positively with BMI within normal range (18.5-23.9; r=0.232, P=0.044). Serum tHcy was negatively correlated with HbA1c, (r=-0.196, P=0.021) and positively with serum creatinine (r=0.327, P=0.000), but unrelated to fasting blood glucose (r=-0.098, P=0.250). Multivariate stepwise regression analysis showed serum folic acid, serum creatinine, MNA-SF score and HbA1c were independent determinants of serum tHcy. Conclusion: Elderly subjects have higher serum tHcy level. Compromised renal function, poor nutritional status and lower blood glucose are likely to influence the serum tHcy level. PMID:24179571

  3. Tracer diffusion inside fibrinogen layers.

    PubMed

    Cieśla, Michał; Gudowska-Nowak, Ewa; Sagués, Francesc; Sokolov, Igor M

    2014-01-28

    We investigate the obstructed motion of tracer (test) particles in crowded environments by carrying simulations of two-dimensional Gaussian random walk in model fibrinogen monolayers of different orientational ordering. The fibrinogen molecules are significantly anisotropic and therefore they can form structures where orientational ordering, similar to the one observed in nematic liquid crystals, appears. The work focuses on the dependence between level of the orientational order (degree of environmental crowding) of fibrinogen molecules inside a layer and non-Fickian character of the diffusion process of spherical tracer particles moving within the domain. It is shown that in general particles motion is subdiffusive and strongly anisotropic, and its characteristic features significantly change with the orientational order parameter, concentration of fibrinogens, and radius of a diffusing probe. PMID:25669566

  4. Significance of dietary folate intake, homocysteine levels and MTHFR 677 C>T genotyping in South African patients diagnosed with depression: test development for clinical application.

    PubMed

    Delport, Darnielle; Schoeman, Renata; van der Merwe, Nicole; van der Merwe, Lize; Fisher, Leslie R; Geiger, Dieter; Kotze, Maritha J

    2014-06-01

    Low folate intake in the presence of the functional MTHFR 677 C > T (rs1801133) polymorphism is an important cause of elevated homocysteine levels previously implicated in major depressive disorder (MDD) and many other chronic diseases. In this study the clinical relevance and inter-relationship of these aspects were evaluated in 86 South African patients diagnosed with MDD and 97 population-matched controls participating in a chronic diseases screening program. A questionnaire-based clinical and nutrition assessment was performed, homocysteine levels determined, and all study participants genotyped for MTHFR 677 C > T (rs1801133) using allele-specific TaqMan technology. The folate score was found to be significantly lower in the patient group compared to controls (p = 0.003) and correlated with increased body mass index (BMI), particularly in females with MDD (p = 0.009). BMI was significantly higher in the MDD patients compared with controls after adjustment for age and sex (p = 0.015), but this association was no longer significant after further adjustment for the level of folate intake in the diet. In MDD patients but not controls, the minor T-allele of MTHFR 677 C > T was associated with increased BMI (p = 0.032), which in turn correlated significantly with increased homocysteine levels. The significant association between BMI and homocysteine levels was observed in both the MDD patient (p = 0.049) and control (p = 0.018) study groups. The significantly higher homocysteine levels observed in MDD patients compared to controls after adjustment for age and sex (p = 0.030), therefore appears to be mediated by the effects of MTHFR 677 C > T and low folate intake on BMI. Detection of the low-penetrance MTHFR 677 C > T mutation reinforces the importance of folate intake above the recommended daily dose to prevent or restore dysfunction of the methylation pathway.

  5. A Phospholipid-Protein Complex from Antarctic Krill Reduced Plasma Homocysteine Levels and Increased Plasma Trimethylamine-N-Oxide (TMAO) and Carnitine Levels in Male Wistar Rats

    PubMed Central

    Bjørndal, Bodil; Ramsvik, Marie S.; Lindquist, Carine; Nordrehaug, Jan E.; Bruheim, Inge; Svardal, Asbjørn; Nygård, Ottar; Berge, Rolf K.

    2015-01-01

    Seafood is assumed to be beneficial for cardiovascular health, mainly based on plasma lipid lowering and anti-inflammatory effects of n-3 polyunsaturated fatty acids. However, other plasma risk factors linked to cardiovascular disease are less studied. This study aimed to penetrate the effect of a phospholipid-protein complex (PPC) from Antarctic krill on one-carbon metabolism and production of trimethylamine-N-oxide (TMAO) in rats. Male Wistar rats were fed isoenergetic control, 6%, or 11% PPC diets for four weeks. Rats fed PPC had reduced total homocysteine plasma level and increased levels of choline, dimethylglycine and cysteine, whereas the plasma level of methionine was unchanged compared to control. PPC feeding increased the plasma level of TMAO, carnitine, its precursors trimethyllysine and γ-butyrobetaine. There was a close correlation between plasma TMAO and carnitine, trimethyllysine, and γ-butyrobetaine, but not between TMAO and choline. The present data suggest that PPC has a homocysteine lowering effect and is associated with altered plasma concentrations of metabolites related to one-carbon metabolism and B-vitamin status in rats. Moreover, the present study reveals a non-obligatory role of gut microbiota in the increased plasma TMAO level as it can be explained by the PPC’s content of TMAO. The increased level of carnitine and carnitine precursors is interpreted to reflect increased carnitine biosynthesis. PMID:26371012

  6. High serum homocysteine levels correlate with a decrease in the blood flow velocity of the ophthalmic artery in highway toll collectors.

    PubMed

    Memişoğullari, Ramazan; Yüksel, Harun; Coskun, Abdurrahman; Yüksel, Hatice Kurt; Yazgan, Omer; Bilgin, Cahit

    2007-07-01

    Highway workers, such as policemen, automotive service companies, and toll collectors, are placed at risk of the accelerated atherosclerotic process, since recent studies have suggested that exposure to exhaust particles and ambient air pollution increases carotid intima-media thickness and reduces ocular blood flow velocity. Therefore, we assessed the relationship between serum homocysteine, a potential parameter for atherosclerosis, and the ocular blood flow velocity and the resistivity index in highway toll collectors. The peak systolic and end diastolic flow velocities and the resistivity index were measured in 22 toll collectors and 24 control subjects by color Doppler ultrasonography. The resistivity index, which is an indirect measure of the atherosclerotic process, was calculated: resistivity index = (peak systolic velocity - end diastolic velocity)/peak systolic velocity. Serum homocysteine levels were determined by fluorometric high-performance liquid chromatography. In the highway toll collectors, the serum homocysteine level (14.4 +/- 4.8 micromol/l; p < 0.005) and the resistivity index of the ophthalmic artery (0.741 +/- 0.015; p < 0.05) were higher and the ophthalmic blood flow velocity (33.0 +/- 3.0 cm/s; p < 0.001) was lower than those in the controls (10.6 +/- 3.1 micromol/l; 0.728 +/- 0.023; 36.8 +/- 2.2 cm/s; respectively). There were significant correlations between the serum homocysteine level and ophthalmic artery resistivity index in both highway toll collectors (p < 0.001) and controls (p < 0.005). Exposure to exhaust particles might increase the serum homocysteine level, which in turn could lead to the decreased ocular blood flow and the increased resistivity index. PMID:17592212

  7. Increased Glutamate and Homocysteine and Decreased Glutamine Levels in Autism: A Review and Strategies for Future Studies of Amino Acids in Autism

    PubMed Central

    Ghanizadeh, Ahmad

    2013-01-01

    There are many reports about the significant roles of some amino acids in neurobiology and treatment of autism. This is a critical review of amino acids levels in autism. No published review article about the level of amino acids in autism was found. The levels of glutamate and homocystein are increased in autism while the levels of glutamine and tryptophan are decreased. Findings regarding the plasma levels of taurine and lysine are controversial. The urinary levels of homocysteine and essential amino acids in both the untreated and treated autistic children are significantly less than those in the controls. The current literature suffers from many methodological shortcomings which needed to be considered in future studies. Some of them are age, gender, developmental level, autism symptoms severity, type of autism spectrum disorders, medical comorbidities, intelligent quotient, diet, concomitant medications, body mass index, and technical method of assessment of amino acids. PMID:24167375

  8. Increased glutamate and homocysteine and decreased glutamine levels in autism: a review and strategies for future studies of amino acids in autism.

    PubMed

    Ghanizadeh, Ahmad

    2013-01-01

    There are many reports about the significant roles of some amino acids in neurobiology and treatment of autism. This is a critical review of amino acids levels in autism. No published review article about the level of amino acids in autism was found. The levels of glutamate and homocystein are increased in autism while the levels of glutamine and tryptophan are decreased. Findings regarding the plasma levels of taurine and lysine are controversial. The urinary levels of homocysteine and essential amino acids in both the untreated and treated autistic children are significantly less than those in the controls. The current literature suffers from many methodological shortcomings which needed to be considered in future studies. Some of them are age, gender, developmental level, autism symptoms severity, type of autism spectrum disorders, medical comorbidities, intelligent quotient, diet, concomitant medications, body mass index, and technical method of assessment of amino acids. PMID:24167375

  9. Relationship between plasma total homocysteine level and dietary caffeine and vitamin B6 intakes in pregnant women.

    PubMed

    Shiraishi, Mie; Haruna, Megumi; Matsuzaki, Masayo; Ota, Erika; Murayama, Ryoko; Sasaki, Satoshi; Yeo, SeonAe; Murashima, Sachiyo

    2014-06-01

    A high total homocysteine (tHcy) level during pregnancy is a risk factor for adverse perinatal outcomes, such as fetal growth restriction and preeclampsia. Caffeine is assumed to increase tHcy levels by acting as a vitamin B6 antagonist. The objective of this study was to examine a relationship between circulating tHcy levels and dietary caffeine and vitamin B6 intakes in pregnant Japanese women. A total of 321 healthy women with singleton pregnancies were recruited in metropolitan Tokyo, from June to December 2008, resulting in the final number included in the study as 254. Dietary caffeine intakes did not correlate with plasma tHcy levels. When we analyzed the data according to caffeinated beverages, caffeinated tea consumption was positively associated with plasma tHcy levels only among the women with a high intake of vitamin B6 , after controlling for confounding factors (P = 0.029). No correlation between coffee consumption and plasma tHcy levels was found. Pregnant Japanese women might need to cut down the consumption of caffeinated tea as well as take sufficient vitamin B6 in order to prevent the tHcy levels from increasing.

  10. Polymorphism in the methylenetetrahydrofolate reductase (C677T) gene and homocysteine levels: a comparison in Brazilian patients with coronary arterial disease, ischemic stroke and peripheral arterial obstructive disease.

    PubMed

    Sabino, Adriano; Fernandes, Ana Paula; Lima, Luciana Moreira; Ribeiro, Daniel Dias; Sousa, Marinez Oliveira; de Castro Santos, Maria Elizabeth Rennó; Mota, Ana Paula Lucas; Dusse, Luci Maria Sant'Ana; das Graças Carvalho, Maria

    2009-01-01

    This study aimed to compare plasma levels of total homocysteine (tHcy) in different arterial events as well as to investigate an association between homocysteine levels and C677T polymorphism in Brazilian patients. A total of 145 subjects were enrolled in this study including 43 patients with coronary arterial disease (CAD), 21 with ischemic stroke (IS), 44 with peripheral arterial obstructive disease (PAOD) and 37 control subjects. A preliminary analysis showed significant difference for tHcy plasma levels between patients with CAD (P = 0.003) or PAOD (P = 0.03) compared to controls. However, after adjustment for sex, age, total cholesterol, LDL, diabetes, tabagism or C677T polymorphism, no significant differences were detected in tHcy levels among patients groups and controls. No significant correlation was demonstrated for C677T polymorphism and homocysteine levels. These results indicate that increased Hcy levels may not be considered an independent risk factor for atherothrombotic diseases in Brazilian patients. PMID:18040753

  11. Aerobic Physical Exercise Improved the Cognitive Function of Elderly Males but Did Not Modify Their Blood Homocysteine Levels

    PubMed Central

    Antunes, Hanna Karen M.; De Mello, Marco Túlio; de Aquino Lemos, Valdir; Santos-Galduróz, Ruth Ferreira; Camargo Galdieri, Luciano; Amodeo Bueno, Orlando Francisco; Tufik, Sergio; D'Almeida, Vânia

    2015-01-01

    Background Physical exercise influences homocysteine (Hcy) concentrations, cognitive function and the metabolic profile. The purpose of this study was to investigate the influence of regular physical exercise on Hcy levels, the metabolic profile and cognitive function in healthy elderly males before and after an endurance exercise program. Methods Forty-five healthy and sedentary volunteers were randomized into 2 groups: (1) a control group asked not to change their normal everyday activities and not to start any regular physical exercise program and (2) an experimental group trained at a heart rate intensity corresponding to ventilatory threshold 1 (VT-1) for 60 min/day 3 times weekly on alternate days for 6 months using a cycle ergometer. All volunteers underwent cognitive evaluations, blood sample analyses and ergospirometric assessments. Results A significant improvement in cognitive function was observed in the experimental group compared with the control group (p < 0.05). No significant changes in Hcy levels were observed in the experimental group (p > 0.05), but there was a significant increase in peak oxygen consumption and workload at VT-1 as well as a significant improvement in cholesterol, triglycerides, HDL, glucose, alkaline phosphatase, urea, T3, T4 and prostate-specific antigen compared with the control group (p < 0.05). Conclusion The data suggest that a physical exercise program does not reduce Hcy levels in healthy elderly males, although it improves the cardiovascular and metabolic profile as well as cognitive function. PMID:25759715

  12. Serum levels of homocysteine, folate and vitamin B12 in patients with vitiligo before and after treatment with narrow band ultraviolet B phototherapy and in a group of controls.

    PubMed

    Ataş, Hatice; Cemil, Bengü Çevirgen; Gönül, Müzeyyen; Baştürk, Eda; Çiçek, Emel

    2015-07-01

    The association between vitamin B12, folate, homocysteine and vitiligo were studied in several studies, but the results are contradictory. Narrow-band ultraviolet B (NBUVB) phototherapy is now considered as a gold standard for the treatment of diffuse vitiligo. The effects of NBUVB phototherapy on both vitamin B12, folate and homocysteine levels have not been studied in vitiligo patients yet. Serum levels of vitamin B12, folate and homocysteine were measured in vitiligo patients and control group and also both before and after NBUVB phototherapy in vitiligo patients. While levels of homocysteine in patients with vitiligo were significantly higher than controls (16.9±8.4 vs. 10. 9±3.4 μmol/L; p<0,001) vitamin B12 and folate levels were not different (p>0.05). NBUVB phototherapy led to a 33.7±21.9% (0-75%) response in patients with vitiligo after 80 seccions. Treatment with NBUVB improved vitiligo and decreased serum levels of vitamin B12 (375±151 vs. 346±119 pg/ml, p=0.024), while serum levels of folate and homocysteine did not change significantly after treatment (p=0.914, p=0.127). Further studies are needed to clarify the influence of NBUVB phototherapy on folate, vitamin B12 and homocysteine levels in patients with vitiligo. Furthermore, studies with the analysis of skin levels of homocysteine rather than circulating levels may be useful to elucidate the effects of phototherapy on homocysteine levels.

  13. Diagnosis of congenital fibrinogen disorders.

    PubMed

    Lebreton, Aurélien; Casini, Alessandro

    2016-08-01

    Congenital fibrinogen disorders comprise quantitative disorders defined by a complete absence (afibrinogenemia) or by a decreased level (hypofibrinogenemia) of circulating fibrinogen and qualitative disorders characterized by a discrepancy between the activity and the antigenic levels of fibrinogen (dysfibrinogenemia and hypodysfibrinogenemia). The biological diagnosis is based on a standard haemostasis assessment. All the coagulation tests that depend on the formation of fibrin as the end point are affected; although in dysfibrinogenemia the specificity and sensitivity of routine test depend on reagent and techniques. A genetic exploration permits to confirm the diagnosis and may enhance the prediction of the patient's phenotype. Homozygous or composite heterozygous null mutations are most often responsible for afibrinogenemia while hypofibrinogenemic patients are mainly heterozygous carrier of an afibrinogenemic allele. Heterozygous missense mutations are prevalent in dysfibrinogenemia, with two hot spot localized in exon 2 of the FGA and in the exon 8 of the FGG. The correlation between phenotype and genotype has been identified in some fibrinogen variants, including six mutations clustered in exons 8 and 9 of the FGG leading to hypofibrinogenemia with hepatic inclusions of abnormal fibrinogen aggregates as well as a few mutations associated with an increase risk of thrombotic events. A familial screening and additional functional assays should be carried out when possible.

  14. Assessment of Folic Acid Supplementation in Pregnant Women by Estimation of Serum Levels of Tetrahydrofolic Acid, Dihydrofolate Reductase, and Homocysteine.

    PubMed

    Naithani, Manisha; Saxena, Vartika; Mirza, Anissa Atif; Kumari, Ranjeeta; Sharma, Kapil; Bharadwaj, Jyoti

    2016-01-01

    Background. Status of folic acid use in pregnant women of the hilly regions in North India was little known. This study was carried out to assess the folic acid use and estimate folate metabolites in pregnant women of this region. Materials and Methods. This cross-sectional study is comprised of 76 pregnant women, whose folic acid supplementation was assessed by a questionnaire and serum levels of homocysteine, tetrahydrofolic acid (THFA), and dihydrofolate reductase (DHFR) were estimated using Enzyme Linked Immunoassays. Results. The study data revealed awareness of folic acid use during pregnancy was present in 46.1% and 23.7% were taking folic acid supplements. The study depicted that there was no statistically significant difference between serum levels of THFA and DHFR in pregnant women with and without folic acid supplements (p = 0.790). Hyperhomocysteinemia was present in 15.78% of the participants. Conclusion. Less awareness about folic acid supplementation and low use of folic acid by pregnant women were observed in this region. Sufficient dietary ingestion may suffice for the escalated requirements in pregnancy, but since this cannot be ensured, hence folic acid supplementation should be made as an integral part of education and reproductive health programs for its better metabolic use, growth, and development of fetus.

  15. Assessment of Folic Acid Supplementation in Pregnant Women by Estimation of Serum Levels of Tetrahydrofolic Acid, Dihydrofolate Reductase, and Homocysteine

    PubMed Central

    Saxena, Vartika; Mirza, Anissa Atif; Kumari, Ranjeeta; Sharma, Kapil; Bharadwaj, Jyoti

    2016-01-01

    Background. Status of folic acid use in pregnant women of the hilly regions in North India was little known. This study was carried out to assess the folic acid use and estimate folate metabolites in pregnant women of this region. Materials and Methods. This cross-sectional study is comprised of 76 pregnant women, whose folic acid supplementation was assessed by a questionnaire and serum levels of homocysteine, tetrahydrofolic acid (THFA), and dihydrofolate reductase (DHFR) were estimated using Enzyme Linked Immunoassays. Results. The study data revealed awareness of folic acid use during pregnancy was present in 46.1% and 23.7% were taking folic acid supplements. The study depicted that there was no statistically significant difference between serum levels of THFA and DHFR in pregnant women with and without folic acid supplements (p = 0.790). Hyperhomocysteinemia was present in 15.78% of the participants. Conclusion. Less awareness about folic acid supplementation and low use of folic acid by pregnant women were observed in this region. Sufficient dietary ingestion may suffice for the escalated requirements in pregnancy, but since this cannot be ensured, hence folic acid supplementation should be made as an integral part of education and reproductive health programs for its better metabolic use, growth, and development of fetus. PMID:27064332

  16. Prognostic Value of Elevated Homocysteine Levels in Korean Patients with Coronary Artery Disease: A Propensity Score Matched Analysis

    PubMed Central

    Kwon, Sung Woo; Kim, Jong-Youn; Suh, Young Ju; Lee, Dae Hyung; Yoon, Young Won; Lee, Byoung Kwon; Jung, Young-Hak; Choi, Eui-Young; Hong, Bum-Kee; Rim, Se-Joong

    2016-01-01

    Background and Objectives We sought to determine whether an elevated homocysteine (Hcy) level is associated with a worse prognosis in Korean patients with coronary artery disease (CAD). Subjects and Methods A total of 5839 patients (60.4% male, mean age 61.3±11.2 years) with CAD were enrolled from 2000 to 2010 at Gangnam Severance Hospital. CAD was diagnosed by invasive coronary angiography. Laboratory values including Hcy level were obtained on the day of coronary angiography and analyses were performed shortly after sampling. Patients were divided into two groups according to their Hcy levels. Baseline risk factors, coronary angiographic findings, length of follow-up, and composite endpoints including cardiac death (CD) and non-fatal myocardial infarction (NFMI) were recorded. 1:1 propensity score matched analysis was also performed. Results Over a mean follow-up period of 4.4±2.5 years, there were 132 composite endpoints (75 CD and 57 NFMI) with an event rate of 2.3%. Mean Hcy level was 9.9±4.3 µmol/L (normal Hcy 7.9±1.5 µmol/L and elevated Hcy 13.9±5.1 µmol/L). Kaplan-Meier survival analysis showed an association of elevated Hcy level with worse prognosis (p<0.0001). In addition, a multivariate Cox regression analysis showed an association of elevated Hcy level with worse prognosis for both the entire cohort (hazard ratio [HR] 2.077, 95% confidence interval [CI] 1.467-2.941, p<0.0001) and the propensity score matched cohort (HR 1.982, 95% CI 1.305-3.009, p=0.001). Conclusion Elevated Hcy level is associated with worse outcomes in Korean patients with CAD. PMID:27014345

  17. Homocysteine Homeostasis and Betaine-Homocysteine S-Methyltransferase Expression in the Brain of Hibernating Bats

    PubMed Central

    Zhang, Yijian; Zhu, Tengteng; Wang, Lina; Pan, Yi-Hsuan; Zhang, Shuyi

    2013-01-01

    Elevated homocysteine is an important risk factor that increases cerebrovascular and neurodegenerative disease morbidity. In mammals, B vitamin supplementation can reduce homocysteine levels. Whether, and how, hibernating mammals, that essentially stop ingesting B vitamins, maintain homocysteine metabolism and avoid cerebrovascular impacts and neurodegeneration remain unclear. Here, we compare homocysteine levels in the brains of torpid bats, active bats and rats to identify the molecules involved in homocysteine homeostasis. We found that homocysteine does not elevate in torpid brains, despite declining vitamin B levels. At low levels of vitamin B6 and B12, we found no change in total expression level of the two main enzymes involved in homocysteine metabolism (methionine synthase and cystathionine β-synthase), but a 1.85-fold increase in the expression of the coenzyme-independent betaine-homocysteine S-methyltransferase (BHMT). BHMT expression was observed in the amygdala of basal ganglia and the cerebral cortex where BHMT levels were clearly elevated during torpor. This is the first report of BHMT protein expression in the brain and suggests that BHMT modulates homocysteine in the brains of hibernating bats. BHMT may have a neuroprotective role in the brains of hibernating mammals and further research on this system could expand our biomedical understanding of certain cerebrovascular and neurodegenerative disease processes. PMID:24376891

  18. Association of seven functional polymorphisms of one-carbon metabolic pathway with total plasma homocysteine levels and susceptibility to Parkinson's disease among South Indians.

    PubMed

    Kumudini, Nadella; Uma, Addepally; Naushad, Shaik Mohammad; Mridula, Rukmini; Borgohain, Rupam; Kutala, Vijay Kumar

    2014-05-01

    This study from South India was performed to ascertain the impact of seven functional polymorphisms of one-carbon metabolic pathway on total plasma homocysteine levels and susceptibility to PD. A total of 151 cases of Parkinson's disease and 416 healthy controls were analyzed for fasting plasma homocysteine levels by reverse phase HPLC. PCR-RFLP approaches were used to analyze glutamate carboxypeptidase II (GCPII) 1561 C>T, reduced folate carrier 1 (RFC1) 80 G>A, cytosolic serine hydroxymethyl transferase (cSHMT) 1420 C>T, methylene tetrahydrofolate reductase (MTHFR) 677 C>T, methionine synthase (MTR) 2756 A>G and methionine synthase reductase (MTRR) 66 A>G polymorphisms. PCR-AFLP was used for the analysis of thymidylate synthase (TYMS) 5'-UTR 28bp tandem repeat. PD cases exhibited elevated plasma homocysteine levels compared to controls (men: 28.8 ± 6.9 vs. 16.4 ± 8.8 μmol/L; women: 25.4 ± 5.3 vs. 11.2 ± 5.1μmol/L). Homocysteine levels showed positive correlation with male gender (r=0.39, p<0.0001) and MTRR 66 A>G (r=0.31, p<0.0001) whereas an inverse correlation was observed with cSHMT 1420 C>T polymorphism. MTRR 66 A>G polymorphism showed independent risk for PD (OR: 3.42, 95% CI: 2.35-4.98) whereas cSHMT 1420 C>T conferred protection against PD (OR: 0.11, 95% CI: 0.07-0.17). Multifactor dimensionality reduction analysis showed synergistic interactions between MTHFR 677 C>T and MTRR 66 A>G, whereas cSHMT 1420 C>T exhibited counteracting interactions in altering susceptibility to PD. To conclude, PD cases exhibited hyperhomocysteinemia and MTRR 66 A>G and cSHMT 1420 C>T gene variants were shown to modulate PD risk by altering the homocysteine levels.

  19. Fibrinogen level deteriorates before other routine coagulation parameters and massive transfusion in the early phase of severe trauma: a retrospective observational study.

    PubMed

    Hayakawa, Mineji; Gando, Satoshi; Ono, Yuichi; Wada, Takeshi; Yanagida, Yuichiro; Sawamura, Atsushi

    2015-02-01

    In trauma, hemostatic functions should be maintained appropriately to prevent massive bleeding. This study elucidated the time-dependent changes in platelet count and coagulation variables, and the effects of disseminated intravascular coagulation (DIC) on these changes during the early phase of trauma. Trauma patients with an injury severity score ≥16 were enrolled. The critical levels of platelet count and coagulation variables were defined according to recent trauma guidelines. Massive transfusion was defined as >10 units red cell concentrate. The time from arrival at the emergency department to reaching the critical levels and meeting the criteria for massive transfusion were evaluated. Eighty trauma patients were enrolled; 35 were diagnosed with DIC on arrival. Among all patients, fibrinogen levels reached the critical level earliest among routine coagulation parameters; other routine coagulation parameters deteriorated after the patients met the criteria for massive transfusion. Routine coagulation parameters reached their critical levels earlier in DIC patients than patients without DIC. Massive transfusion was performed more frequently in DIC patients, who met the criteria earlier. During the early phase of trauma, fibrinogen levels deteriorate earlier than other routine coagulation parameters, especially in DIC patients.

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

    PubMed Central

    2013-01-01

    Background An 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. Methods 108 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). Results Compared 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. Conclusion Our 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 slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1623509866881834 PMID:23631751

  1. Comparative Assessment of Vitamin-B12, Folic Acid and Homocysteine Levels in Relation to p53 Expression in Megaloblastic Anemia

    PubMed Central

    Yadav, Manish K.; Manoli, Nandini M.

    2016-01-01

    Background Megaloblastic anemia (MBA), also known as macrocytic anemia, is a type of anemia characterized by decreased number of RBCs as well as the presence of unusually large, abnormal and poorly developed erythrocytes (megaloblasts), which fail to enter blood circulation due to their larger size. Lack of vitamin-B12 (VB12) and / or folate (Vitamin-B9, VB9) with elevated homocysteine is the key factor responsible for megaloblastic anemia. Prior studies have demonstrated the induction of apoptosis in these abnormal under-developed erythrocytes. However, it is not clear whether this apoptosis induction is due to elevated p53 level or due to any other mechanism. Furthermore, it is also not fully known whether decreased vitamin-B12 and / or folate are responsible for apoptosis induction mediated by p53 in pre-erythroblasts. Methods Levels of serum VB9, VB12 and homocysteine in 50 patients suffering from MBA were compared with 50 non-megaloblastic anemia control subjects, who were referred by the clinicians for bone marrow examination for medical conditions other than MBA. Next, we have measured the p53 expression in the paraffin embedded blocks prepared from bone marrow biopsy, using immunohistochemistry, and the expression levels correlated with VB9 and VB12 levels. Results Out of 50 MBA patients 40 (80%) and 44 (88%) subjects had very low VB12 and VB9 levels respectively. In contrast, only 2 (4%) and 12 (24%) non-megaloblastic anemia controls, out of 50 subjects, had low VB12 and VB9 respectively. Correlating with low vitamin B9 and B12, the homocysteine levels were high in 80% cases. But, only 20% non-megaloblastic controls exhibited high homocysteine in plasma. Immunohistochemical analysis for p53 expression showed a significantly high level of expression in MBA cases and no—or very low—expression in control subjects. Our correlation studies comparing the VB12 and VB9 levels with p53 expression concludes unusually high p53 levels in patients suffering from VB

  2. Rare and low-frequency variants and their association with plasma levels of fibrinogen, FVII, FVIII, and vWF.

    PubMed

    Huffman, Jennifer E; de Vries, Paul S; Morrison, Alanna C; Sabater-Lleal, Maria; Kacprowski, Tim; Auer, Paul L; Brody, Jennifer A; Chasman, Daniel I; Chen, Ming-Huei; Guo, Xiuqing; Lin, Li-An; Marioni, Riccardo E; Müller-Nurasyid, Martina; Yanek, Lisa R; Pankratz, Nathan; Grove, Megan L; de Maat, Moniek P M; Cushman, Mary; Wiggins, Kerri L; Qi, Lihong; Sennblad, Bengt; Harris, Sarah E; Polasek, Ozren; Riess, Helene; Rivadeneira, Fernando; Rose, Lynda M; Goel, Anuj; Taylor, Kent D; Teumer, Alexander; Uitterlinden, André G; Vaidya, Dhananjay; Yao, Jie; Tang, Weihong; Levy, Daniel; Waldenberger, Melanie; Becker, Diane M; Folsom, Aaron R; Giulianini, Franco; Greinacher, Andreas; Hofman, Albert; Huang, Chiang-Ching; Kooperberg, Charles; Silveira, Angela; Starr, John M; Strauch, Konstantin; Strawbridge, Rona J; Wright, Alan F; McKnight, Barbara; Franco, Oscar H; Zakai, Neil; Mathias, Rasika A; Psaty, Bruce M; Ridker, Paul M; Tofler, Geoffrey H; Völker, Uwe; Watkins, Hugh; Fornage, Myriam; Hamsten, Anders; Deary, Ian J; Boerwinkle, Eric; Koenig, Wolfgang; Rotter, Jerome I; Hayward, Caroline; Dehghan, Abbas; Reiner, Alex P; O'Donnell, Christopher J; Smith, Nicholas L

    2015-09-10

    Fibrinogen, coagulation factor VII (FVII), and factor VIII (FVIII) and its carrier von Willebrand factor (vWF) play key roles in hemostasis. Previously identified common variants explain only a small fraction of the trait heritabilities, and additional variations may be explained by associations with rarer variants with larger effects. The aim of this study was to identify low-frequency (minor allele frequency [MAF] ≥0.01 and <0.05) and rare (MAF <0.01) variants that influence plasma concentrations of these 4 hemostatic factors by meta-analyzing exome chip data from up to 76,000 participants of 4 ancestries. We identified 12 novel associations of low-frequency (n = 2) and rare (n = 10) variants across the fibrinogen, FVII, FVIII, and vWF traits that were independent of previously identified associations. Novel loci were found within previously reported genes and had effect sizes much larger than and independent of previously identified common variants. In addition, associations at KCNT1, HID1, and KATNB1 identified new candidate genes related to hemostasis for follow-up replication and functional genomic analysis. Newly identified low-frequency and rare-variant associations accounted for modest amounts of trait variance and therefore are unlikely to increase predicted trait heritability but provide new information for understanding individual variation in hemostasis pathways. PMID:26105150

  3. Rare and low-frequency variants and their association with plasma levels of fibrinogen, FVII, FVIII, and vWF

    PubMed Central

    Huffman, Jennifer E.; de Vries, Paul S.; Morrison, Alanna C.; Sabater-Lleal, Maria; Kacprowski, Tim; Auer, Paul L.; Brody, Jennifer A.; Chasman, Daniel I.; Chen, Ming-Huei; Guo, Xiuqing; Lin, Li-An; Marioni, Riccardo E.; Müller-Nurasyid, Martina; Yanek, Lisa R.; Pankratz, Nathan; Grove, Megan L.; de Maat, Moniek P. M.; Cushman, Mary; Wiggins, Kerri L.; Qi, Lihong; Sennblad, Bengt; Harris, Sarah E.; Polasek, Ozren; Riess, Helene; Rivadeneira, Fernando; Rose, Lynda M.; Goel, Anuj; Taylor, Kent D.; Teumer, Alexander; Uitterlinden, André G.; Vaidya, Dhananjay; Yao, Jie; Tang, Weihong; Levy, Daniel; Waldenberger, Melanie; Becker, Diane M.; Folsom, Aaron R.; Giulianini, Franco; Greinacher, Andreas; Hofman, Albert; Huang, Chiang-Ching; Kooperberg, Charles; Silveira, Angela; Starr, John M.; Strauch, Konstantin; Strawbridge, Rona J.; Wright, Alan F.; McKnight, Barbara; Franco, Oscar H.; Zakai, Neil; Mathias, Rasika A.; Psaty, Bruce M.; Ridker, Paul M.; Tofler, Geoffrey H.; Völker, Uwe; Watkins, Hugh; Fornage, Myriam; Hamsten, Anders; Deary, Ian J.; Boerwinkle, Eric; Koenig, Wolfgang; Rotter, Jerome I.; Hayward, Caroline; Dehghan, Abbas; Reiner, Alex P.; O’Donnell, Christopher J.

    2015-01-01

    Fibrinogen, coagulation factor VII (FVII), and factor VIII (FVIII) and its carrier von Willebrand factor (vWF) play key roles in hemostasis. Previously identified common variants explain only a small fraction of the trait heritabilities, and additional variations may be explained by associations with rarer variants with larger effects. The aim of this study was to identify low-frequency (minor allele frequency [MAF] ≥0.01 and <0.05) and rare (MAF <0.01) variants that influence plasma concentrations of these 4 hemostatic factors by meta-analyzing exome chip data from up to 76 000 participants of 4 ancestries. We identified 12 novel associations of low-frequency (n = 2) and rare (n = 10) variants across the fibrinogen, FVII, FVIII, and vWF traits that were independent of previously identified associations. Novel loci were found within previously reported genes and had effect sizes much larger than and independent of previously identified common variants. In addition, associations at KCNT1, HID1, and KATNB1 identified new candidate genes related to hemostasis for follow-up replication and functional genomic analysis. Newly identified low-frequency and rare-variant associations accounted for modest amounts of trait variance and therefore are unlikely to increase predicted trait heritability but provide new information for understanding individual variation in hemostasis pathways. PMID:26105150

  4. Elevated homocysteine levels in human immunodeficiency virus-infected patients under antiretroviral therapy: A meta-analysis

    PubMed Central

    Deminice, Rafael; Silva, Talita Capoani Vieira; de Oliveira, Vitor Hugo Fernando

    2015-01-01

    AIM: To evaluate the association between the levels of homocysteine (Hcy), folate, vitamin B12 in human immunodeficiency virus (HIV)-infected patients who were treated with antiretroviral therapy (ART) or not treated with ART. METHODS: The PubMed and Scielo databases were searched. Eligible studies regarding plasma Hcy level in HIV-infected patients were firstly identified. After careful analysis by two independent researches, the identified articles were included in the review according to two outcomes (1) Hcy, folate and vitamin B12 blood concentration in HIV-infected subjects vs health controls and; (2) Hcy blood concentration in HIV-infected subjects under ART vs not treated with ART. RevMan (version 5.2) was employed for data synthesis. RESULTS: A total of 12 studies were included in outcome 1 (1649 participants, 932 cases and 717 controls). Outcome 1 meta-analysis demonstrated higher plasma Hcy (2.05 µmol/L; 95%CI: 0.10 to 4.00, P < 0.01) and decreased plasma folate concentrations (-2.74 ng/mL; 95%CI: -5.18 to -0.29, P < 0.01) in HIV-infected patients compared to healthy controls. No changes in vitamin B12 plasma concentration were observed between groups. All studies included in the outcome 2 meta-analysis (1167 participants; 404 HIV-infected exposed to ART and 757 HIV-infected non-ART patients) demonstrated higher mean Hcy concentration in subjects HIV-infected under ART compared to non-ART HIV subjects (4.13 µmol/L; 95%CI: 1.34 to 6.92, P < 0.01). CONCLUSION: This meta-analysis demonstrated that the levels of Hcy and folate, but not vitamin B12, were associated with HIV infection. In addition, Hcy levels were higher in HIV-infected patients who were under ART compared to HIV-infected patients who were not exposed to ART. Our results suggest that hyperhomocysteinemia should be included among the several important metabolic disturbances that are associated with ART in patients with HIV infection. PMID:25964880

  5. Effect of N-acetylcysteine administration on homocysteine level, oxidative damage to proteins, and levels of iron (Fe) and Fe-related proteins in lead-exposed workers.

    PubMed

    Kasperczyk, Sławomir; Dobrakowski, Michał; Kasperczyk, Aleksandra; Romuk, Ewa; Rykaczewska-Czerwińska, Monika; Pawlas, Natalia; Birkner, Ewa

    2016-09-01

    N-Acetylcysteine (NAC) could be included in protocols designed for the treatment of lead toxicity. Therefore, in this study, we decided to investigate the influence of NAC administration on homocysteine (Hcy) levels, oxidative damage to proteins, and the levels of iron (Fe), transferrin (TRF), and haptoglobin (HPG) in lead (Pb)-exposed workers. The examined population (n = 171) was composed of male employees who worked with Pb. They were randomized into four groups. Workers who were not administered any antioxidants, drugs, vitamins, or dietary supplements were classified as the reference group (n = 49). The remaining three groups consisted of workers who were treated orally with NAC at three different doses (1 × 200, 2 × 200, or 2 × 400 mg) for 12 weeks. After the treatment, blood Pb levels significantly decreased in the groups receiving NAC compared with the reference group. The protein concentration was not affected by NAC administration. In contrast, Hcy levels significantly decreased or showed a strong tendency toward lower values depending on the NAC dose. Levels of the protein carbonyl groups were significantly decreased in all of the groups receiving NAC. Conversely, glutamate dehydrogenase activity was significantly elevated in all of the groups receiving NAC, while the level of protein thiol groups was significantly elevated only in the group receiving 200 mg of NAC. Treatment with NAC did not significantly affect Fe and TRF levels, whereas HPG levels showed a tendency toward lower values. Treatment with NAC normalized the level of Hcy and decreased oxidative stress as measured by the protein carbonyl content; this effect occurred in a dose-dependent manner. Moreover, small doses of NAC elevated the levels of protein thiol groups. Therefore, NAC could be introduced as an alternative therapy for chronic Pb toxicity in humans. PMID:25731901

  6. The effects of long-term resistance exercise on the relationship between neurocognitive performance and GH, IGF-1, and homocysteine levels in the elderly

    PubMed Central

    Tsai, Chia-Liang; Wang, Chun-Hao; Pan, Chien-Yu; Chen, Fu-Chen

    2015-01-01

    This study aimed to investigate the effects of a long-term resistance exercise intervention on executive functions in healthy elderly males, and to further understand the potential neurophysiological mechanisms mediating the changes. The study assessed forty-eight healthy elderly males randomly assigned to exercise (n = 24) or control (n = 24) groups. The assessment included neuropsychological and neuroelectric measures during a variant of the oddball task paradigm, as well as growth hormone (GH), insulin-like growth factor-1 (IGF-1), and homocysteine levels at baseline and after either a 12 month intervention of resistance exercise training or control period. The results showed that the control group had a significantly lower accuracy rate and smaller P3a and P3b amplitudes in the oddball condition after 12 months. The exercise group exhibited improved reaction times (RTs), sustained P3a and P3b amplitudes, increased levels of serum IGF-1, and decreased levels of serum homocysteine. The changes in IGF-1 levels were significantly correlated with the changes in RT and P3b amplitude of the oddball condition in the exercise group. In conclusion, significantly enhanced serum IGF-1 levels after 12 months of resistance exercise were inversely correlated with neurocognitive decline in the elderly. These findings suggest that regular resistance exercise might be a promising strategy to attenuate the trajectory of cognitive aging in healthy elderly individuals, possibly mediated by IGF-1. PMID:25713518

  7. Fibrinogen reduction and coagulation in cardiac surgery: an investigational study.

    PubMed

    Gielen, Chantal L I; Grimbergen, Jos; Klautz, Robert J M; Koopman, Jaap; Quax, Paul H A

    2015-09-01

    Fibrinogen as precursor of fibrin plays an essential role in clot formation. There are three main mechanisms associated with a reduction in fibrinogen concentration during cardiac surgery: hemodilution, consumption, and degradation. Moreover, early fibrinogen degradation products (FgDPs) can interfere with normal fibrin formation of intact fibrinogen. The aim of this study was to determine the relative contributions of hemodilution, consumption, and degradation to fibrinogen loss in cardiac surgery and to evaluate the effects fibrinogen degradation products on blood clot formation in vitro. First, fibrin and fibrinogen concentrations, their degradation products, hematocrit, and albumin concentrations were compared in 10 patients before and after isolated coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass. Second, ex-vivo fibrinogen supplementation experiments were performed. Finally, the effects of purified FgDPs on clotting time and clot firmness were established in vitro in whole blood by ROTEM. Fibrinogen plasma concentration decreased 30% during surgery. This drop appears to be mainly caused by hemodilution, as both hematocrit and albumin levels decreased and no relevant increase in D-dimer levels and FgDPs was observed. Furthermore, the coagulation profile normalized after addition of purified fibrinogen. Early FgDPs demonstrated a significant impact on in-vitro whole blood clotting. Although early FgDPs have a pronounced effect on blood clot formation in vitro and therefore may induce or enhance in vivo coagulopathy, the drop of fibrinogen concentration seen after CABG surgery (using tranexamic acid) is primarily caused by hemodilution. PMID:26083991

  8. Effects of long-term developmental patterns of adiposity on levels of C-reactive protein and fibrinogen among North-American men and women: the Spokane Heart Study.

    PubMed

    Hoekstra, Trynke; Barbosa-Leiker, Celestina; Wright, Bruce R; Twisk, Jos W R

    2014-01-01

    This study examined the heterogeneity in BMI development by identifying distinct developmental trajectories. These trajectories were further investigated by relating them to markers of low-grade inflammation later in life. Data from approximately 400 healthy volunteers participating in the Spokane Heart Study were collected in 2-year intervals, and four waves of data were available for the current analyses. Body weight was measured by BMI and low-grade inflammation by high-sensitivity C-reactive protein (CRP) and fibrinogen. Up to date statistical techniques, i.e., latent class growth models, were used to analyse heterogeneity in body weight, and linear regressions were run to analyse possible associations between trajectories of body weight and CRP/fibrinogen levels. Six trajectories were identified (three stable, two increasing, and one decreasing) which differed significantly on CRP/fibrinogen levels, highlighting the importance of weight trajectories. The differences were only partly explained by variations in lifestyle habits. PMID:24903324

  9. Effects of long-term developmental patterns of adiposity on levels of C-reactive protein and fibrinogen among North-American men and women: the Spokane Heart Study.

    PubMed

    Hoekstra, Trynke; Barbosa-Leiker, Celestina; Wright, Bruce R; Twisk, Jos W R

    2014-01-01

    This study examined the heterogeneity in BMI development by identifying distinct developmental trajectories. These trajectories were further investigated by relating them to markers of low-grade inflammation later in life. Data from approximately 400 healthy volunteers participating in the Spokane Heart Study were collected in 2-year intervals, and four waves of data were available for the current analyses. Body weight was measured by BMI and low-grade inflammation by high-sensitivity C-reactive protein (CRP) and fibrinogen. Up to date statistical techniques, i.e., latent class growth models, were used to analyse heterogeneity in body weight, and linear regressions were run to analyse possible associations between trajectories of body weight and CRP/fibrinogen levels. Six trajectories were identified (three stable, two increasing, and one decreasing) which differed significantly on CRP/fibrinogen levels, highlighting the importance of weight trajectories. The differences were only partly explained by variations in lifestyle habits.

  10. Inhibition of homocysteine-induced endoplasmic reticulum stress and endothelial cell damage by l-serine and glycine.

    PubMed

    Sim, Woo-Cheol; Han, Inhoi; Lee, Wonseok; Choi, You-Jin; Lee, Kang-Yo; Kim, Dong Gwang; Jung, Seung-Hwan; Oh, Seon-Hee; Lee, Byung-Hoon

    2016-08-01

    Hyperhomocysteinemia is an independent risk factor for several cardiovascular diseases. The use of vitamins to modulate homocysteine metabolism substantially lowers the risk by reducing plasma homocysteine levels. In this study, we evaluated the effects of l-serine and related amino acids on homocysteine-induced endoplasmic reticulum (ER) stress and endothelial cell damage using EA.hy926 human endothelial cells. Homocysteine treatment decreased cell viability and increased apoptosis, which were reversed by cotreatment with l-serine. l-Serine inhibited homocysteine-induced ER stress as verified by decreased glucose-regulated protein 78kDa (GRP78) and C/EBP homologous protein (CHOP) expression as well as X-box binding protein 1 (xbp1) mRNA splicing. The effects of l-serine on homocysteine-induced ER stress are not attributed to intracellular homocysteine metabolism, but instead to decreased homocysteine uptake. Glycine exerted effects on homocysteine-induced ER stress, apoptosis, and cell viability that were comparable to those of l-serine. Although glycine did not affect homocysteine uptake or export, coincubation of homocysteine with glycine for 24h reduced the intracellular concentration of homocysteine. Taken together, l-serine and glycine cause homocysteine-induced endothelial cell damage by reducing the level of intracellular homocysteine. l-Serine acts by competitively inhibiting homocysteine uptake in the cells. However, the mechanism(s) by which glycine lowers homocysteine levels are unclear. PMID:27064126

  11. Inhibition of homocysteine-induced endoplasmic reticulum stress and endothelial cell damage by l-serine and glycine.

    PubMed

    Sim, Woo-Cheol; Han, Inhoi; Lee, Wonseok; Choi, You-Jin; Lee, Kang-Yo; Kim, Dong Gwang; Jung, Seung-Hwan; Oh, Seon-Hee; Lee, Byung-Hoon

    2016-08-01

    Hyperhomocysteinemia is an independent risk factor for several cardiovascular diseases. The use of vitamins to modulate homocysteine metabolism substantially lowers the risk by reducing plasma homocysteine levels. In this study, we evaluated the effects of l-serine and related amino acids on homocysteine-induced endoplasmic reticulum (ER) stress and endothelial cell damage using EA.hy926 human endothelial cells. Homocysteine treatment decreased cell viability and increased apoptosis, which were reversed by cotreatment with l-serine. l-Serine inhibited homocysteine-induced ER stress as verified by decreased glucose-regulated protein 78kDa (GRP78) and C/EBP homologous protein (CHOP) expression as well as X-box binding protein 1 (xbp1) mRNA splicing. The effects of l-serine on homocysteine-induced ER stress are not attributed to intracellular homocysteine metabolism, but instead to decreased homocysteine uptake. Glycine exerted effects on homocysteine-induced ER stress, apoptosis, and cell viability that were comparable to those of l-serine. Although glycine did not affect homocysteine uptake or export, coincubation of homocysteine with glycine for 24h reduced the intracellular concentration of homocysteine. Taken together, l-serine and glycine cause homocysteine-induced endothelial cell damage by reducing the level of intracellular homocysteine. l-Serine acts by competitively inhibiting homocysteine uptake in the cells. However, the mechanism(s) by which glycine lowers homocysteine levels are unclear.

  12. Effects of homocysteine on metabolic pathways in cultured astrocytes.

    PubMed

    Jin, Ying; Brennan, Lorraine

    2008-06-01

    Homocysteine is an amino acid that is an important risk factor for several neurodegenerative diseases such as Alzheimer's and Parkinson's disease. Increased homocysteine levels induce neuronal cell death in a variety of neuronal types. However, very few studies have probed the effects of homocysteine in astrocytes. The present study investigated the effects of homocysteine on primary cultures of astrocytes by exposing astrocytes to 400 microM homocysteine for 20 h. Metabolic extracts of cells were prepared following a 4-h incubation in minimum medium with 5.5 mM [U-(13)C]glucose in the presence or absence of homocysteine and analysed using (13)C NMR. The expression level of pyruvate dehydrogenase kinase isoform 2 (PDK-2), NAD(P)H levels and mitochondrial membrane potential responses were investigated following culture with homocysteine. Metabolomic analysis was performed using (1)H NMR spectroscopy and pattern recognition analysis. Following incubation with homocysteine there was a significant decrease (48%) in the ratio of flux through pyruvate carboxylase (PC) and pyruvate dehydrogenase (PDH) which was due to an increased flux through PDH. In addition, homocysteine culture resulted in a significant reduction in PDK-2 protein expression. Following stimulation with glucose there was a significant increase in NAD(P)H levels and an impaired hyperpolarisation of the mitochondrial membrane in homocysteine-treated cells. Metabolomic analysis showed that the most discriminating metabolites following homocysteine treatment were choline and hypotaurine. In summary, the results demonstrated that sub-lethal concentrations of homocysteine caused significant metabolic changes and altered mitochondrial function in primary cultures of astrocytes. PMID:18417255

  13. Homocysteine and Familial Longevity: The Leiden Longevity Study

    PubMed Central

    Wijsman, Carolien A.; van Heemst, Diana; Rozing, Maarten P.; Slagboom, P. Eline; Beekman, Marian; de Craen, Anton J. M.; Maier, Andrea B.; Westendorp, Rudi G. J.; Blom, Henk J.; Mooijaart, Simon P.

    2011-01-01

    Homocysteine concentrations are a read-out of methionine metabolism and have been related to changes in lifespan in animal models. In humans, high homocysteine concentrations are an important predictor of age related disease. We aimed to explore the association of homocysteine with familial longevity by testing whether homocysteine is lower in individuals that are genetically enriched for longevity. We measured concentrations of total homocysteine in 1907 subjects from the Leiden Longevity Study consisting of 1309 offspring of nonagenarian siblings, who are enriched with familial factors promoting longevity, and 598 partners thereof as population controls. We found that homocysteine was related to age, creatinine, folate, vitamin B levels and medical history of hypertension and stroke in both groups (all p<0.001). However, levels of homocysteine did not differ between offspring enriched for longevity and their partners, and no differences in the age-related rise in homocysteine levels were found between groups (p for interaction 0.63). The results suggest that homocysteine metabolism is not likely to predict familial longevity. PMID:21408159

  14. Homocysteine and migraine. A narrative review.

    PubMed

    Lippi, Giuseppe; Mattiuzzi, Camilla; Meschi, Tiziana; Cervellin, Gianfranco; Borghi, Loris

    2014-06-10

    Recent evidence suggests that migraine is associated with an increased risk of cardiovascular disorders, so that it is increasingly hypothesized that this primary form of headache may be linked to thrombotic diseases by some biological pathways and risk factors. Homocysteine, a sulfur-containing molecule, is now recognized as an independent risk factor for a variety of thrombotic disorders, especially ischemic heart disease and stroke. This article is hence aimed to provide an overview of epidemiological evidence about the association between homocysteine and migraine published in cross-sectional, prospective or interventional studies. Overall, the evidence gathered from cross-sectional studies that measured plasma homocysteine levels suggests that the epidemiological link between the plasma concentration of this biomarker and migraine is very weak, at best. Contradictory evidence emerged from interventional studies, in which treatment of hyperhomocysteinemia with folic acid or vitamin B supplementation was effective to lower plasma homocysteine and decrease frequency and/or severity of migraine. The association remains largely speculative, however, since it could not be clearly demonstrated that these two biological effects were directly linked. The only study that has assessed homocysteine in cerebrospinal fluid reported that the concentration of this biomarker in migraine patients was significantly increased compared to controls. Although this evidence must be obviously confirmed in larger trials, some putative mechanisms may support a causal link between increased generation of homocysteine in the brain environment and migraine.

  15. Studies on chemically modified fibrinogen.

    PubMed

    Kloczewiak, M; Wegrzynowicz, Z; Matthias, F R; Heene, D L; Zajdel, M

    1976-04-30

    Treatment of fibrinogen with maleic acid anhydride renders fibrinogen unclottable depending on the degree of modification of the molecule. According to radioactive studies the release of fibrinopeptides by thrombin or reptilase is undisturbed. The incoagulability is due to inhibition of the polymerization process of fibrinmonomers derived from modified fibronogen, mainly caused by the increase of electronegative charges upon the fibrogen molecule. According to discelectrophoretic analysis modified fibrinogen fails to produce fragments D and E following plasmic digestion, however, may be degraded to high molecular weight products. Modified fibrinogen reveals some similarities to abnormal fibrinogens in congenital dysfibrinogenemia with regard to its functional properties.

  16. Increased CSF Homocysteine in Pathological Gamblers Compared with Healthy Controls

    ERIC Educational Resources Information Center

    Nordin, Conny; Sjodin, Ingemar

    2009-01-01

    Neurocognitive disturbances suggesting a frontal lobe dysfunction have been observed in pathological gamblers and alcohol dependents. Given that a high homocysteine level has been suggested to be a mediating factor in alcohol-related cognitive decline, we have determined homocysteine and cobalamine in cerebrospinal fluid (CSF) obtained from 11…

  17. Elevated Homocysteine Level and Folate Deficiency Associated with Increased Overall Risk of Carcinogenesis: Meta-Analysis of 83 Case-Control Studies Involving 35,758 Individuals

    PubMed Central

    Wu, Wei; Guo, Ye; Cui, Wei

    2015-01-01

    Background Results of the association of folate metabolism and carcinogenesis are conflicting. We performed a meta-analysis to examine the effect of the interaction of serum concentration of homocysteine (Hcy), folate, and vitamin B12 and 5,10-methylenetetrahydrofolate reductase (MTHFR) polymorphism on risk of cancer overall. Method Two reviewers independently searched for all published studies of Hcy and cancer in PubMed, EMBASE-MEDLINE and Chinese databases. Pooled results were reported as odds ratios (ORs) and mean differences and presented with 95% confidence intervals (95% CIs) and 2-sided probability values. Results We identified 83 eligible studies of 15,046 cases and 20,712 controls. High level of Hcy but low level of folate was associated with risk of cancer overall, with little effect by type of cancer or ethnicity. Vitamin B12 level was inversely associated with only urinary-system and gastrointestinal carcinomas and for Asian and Middle Eastern patients. As well, MTHFR C677T, A1298C and G1793A polymorphisms were related to elevated serum level of Hcy, and folate and vitamin B12 deficiency. However, only MTHFR C677T homogeneity/wild-type (TT/CC) polymorphism was positively associated with overall risk of cancer. Conclusion Elevated serum Hcy level and folate deficiency are associated with increased overall risk of cancer. PMID:25985325

  18. Effect of Short-Term Maximal Exercise on Biochemical Markers of Muscle Damage, Total Antioxidant Status, and Homocysteine Levels in Football Players

    PubMed Central

    Hammouda, Omar; Chtourou, Hamdi; Chaouachi, Anis; Chahed, Henda; Ferchichi, Salyma; Kallel, Choumous; Chamari, Karim; Souissi, Nizar

    2012-01-01

    Purpose Prolonged physical exercise results in transient elevations of biochemical markers of muscular damage. This study examined the effect of short-term maximal exercise on these markers, homocysteine levels (Hcy), and total antioxidant status (TAS) in trained subjects. Methods Eighteen male football players participated in this study. Blood samples were collected 5-min before and 3-min after a 30-s Wingate test. Results The results indicated that plasma biochemical markers of muscle injury increased significantly after the Wingate test (P<0.05). Moreover, significant increase of white blood Cells and their main subpopulations (i.e. monocytes, neutrophiles, and lymphocytes) (P<0.001) has been observed. Likewise, uric acid, total bilirubin, and TAS increased significantly after exercise (P<0.05). However, Hcy levels were unaffected by the Wingate test (for 3-min post-exercise measurement). Conclusions Short-term maximal exercise (e.g. 30-s Wingate test) is of sufficient intensity and duration to increase markers of muscle damage, and TAS; but not Hcy levels. Increases in the selected enzymes probably come primarily from muscle damage, rather than liver damage. Moreover, increase of TAS confirms the Wingate test induced oxidative stress. PMID:23342222

  19. Comparison of the effects of pulmonary rehabilitation with chest physical therapy on the levels of fibrinogen and albumin in patients with lung cancer awaiting lung resection: a randomized clinical trial

    PubMed Central

    2014-01-01

    Background Systemic inflammation plays an important role in the initiation, promotion, and progression of lung carcinogenesis. In patients with non-small cell lung cancer (NSCLC), fibrinogen levels correlate with neoplasia. Here we compared the effects of pulmonary rehabilitation (PR) with chest physical therapy (CPT) on fibrinogen and albumin levels in patients with LC and previous inflammatory lung disease awaiting lung resection. Methods We conducted a randomized clinical trial with 24 patients who were randomly assigned to Pulmonary Rehabilitation (PR) and Chest Physical Therapy (CPT) groups. Each group underwent training 5 days weekly for 4 weeks. All patients were assessed before and after four weeks of training through clinical assessment, measurement of fibrinogen and albumin levels, spirometry, 6-minute Walk Test (6MWT), quality of life survey, and anxiety and depression scale. PR involved strength and endurance training, and CPT involved lung expansion techniques. Both groups attended educational classes. Results A mixed between-within subjects analysis of variance (ANOVA) revealed a significant interaction between time (before and after intervention) and group (PR vs. CPT) on fibrinogen levels (F(1, 22) = 0.57, p < 0.0001) and a significant main effect of time (F(1, 22) = 0.68, p = 0.004). Changes in albumin levels were not statistically significant relative to the interaction effect between time and group (F(1, 22) = 0.96, p = 0.37) nor the main effects of time (F(1, 22) = 1.00, p = 1.00) and group (F(1, 22 ) = 0.59, p = 0.45). A mixed between-within subjects ANOVA revealed significant interaction effects between time and group for the peak work rate of the unsupported upper limb exercise (F(1, 22) = 0.77, p = 0.02), endurance time (F(1, 22) = 0.60, p = 0.001), levels of anxiety (F(1, 22) = 0.60, p = 0.002) and depression (F(1, 22) = 0.74, p = 0.02), and the SF-36 physical

  20. Converging Evidence of Mitochondrial Dysfunction in a Yeast Model of Homocysteine Metabolism Imbalance*

    PubMed Central

    Kumar, Arun; John, Lijo; Maity, Shuvadeep; Manchanda, Mini; Sharma, Abhay; Saini, Neeru; Chakraborty, Kausik; Sengupta, Shantanu

    2011-01-01

    An elevated level of homocysteine, a thiol amino acid, is associated with various complex disorders. The cellular effects of homocysteine and its precursors S-adenosylhomocysteine (AdoHcy) and S-adenosylmethionine (AdoMet) are, however, poorly understood. We used Saccharomyces cerevisiae as a model to understand the basis of pathogenicity induced by homocysteine and its precursors. Both homocysteine and AdoHcy but not AdoMet inhibited the growth of the str4Δ strain (which lacks the enzyme that converts homocysteine to cystathionine-mimicking vascular cells). Addition of AdoMet abrogated the inhibitory effect of AdoHcy but not that of homocysteine indicating that an increase in the AdoMet/AdoHcy ratio is sufficient to overcome the AdoHcy-mediated growth defect but not that of homocysteine. Also, the transcriptomic profile of AdoHcy and homocysteine showed gross dissimilarity based on gene enrichment analysis. Furthermore, compared with homocysteine, AdoHcy treatment caused a higher level of oxidative stress in the cells. However, unlike a previously reported response in wild type (Kumar, A., John, L., Alam, M. M., Gupta, A., Sharma, G., Pillai, B., and Sengupta, S. (2006) Biochem. J. 396, 61–69), the str4Δ strain did not exhibit an endoplasmic reticulum stress response. This suggests that homocysteine induces varied response depending on the flux of homocysteine metabolism. We also observed altered expression of mitochondrial genes, defective membrane potential, and fragmentation of the mitochondrial network together with the increased expression of fission genes indicating that the imbalance in homocysteine metabolism has a major effect on mitochondrial functions. Furthermore, treatment of cells with homocysteine or AdoHcy resulted in apoptosis as revealed by annexin V staining and TUNEL assay. Cumulatively, our results suggest that elevated levels of homocysteine lead to mitochondrial dysfunction, which could potentially initiate pro-apoptotic pathways, and

  1. Three-month variation of plasma pentraxin 3 compared with C-reactive protein, albumin and homocysteine levels in haemodialysis patients

    PubMed Central

    Sjöberg, Bodil; Snaedal, Sunna; Stenvinkel, Peter; Qureshi, Abdul Rashid; Heimbürger, Olof; Bárány, Peter

    2014-01-01

    Background Inflammatory markers vary considerably over time in haemodialysis (HD) patients, yet the variability is poorly defined. The aim of the study was to assess changes of plasma levels of pentraxin-3 (PTX-3), C-reactive protein (CRP), albumin and homocysteine (Hcy) over 3 months and the association between the changes in these biomarkers and mortality. Methods In 188 prevalent HD patients, inflammatory markers were measured at inclusion and after 3 months. Mortality was recorded during a median follow-up of 41 months. The changes of the biomarker levels were categorized according to change in tertile for the specific biomarker. The variation was calculated as the intra-class correlation (ICC). Mortality was analysed by Kaplan–Meier and Cox proportional hazards model. The predictive strength was calculated for single measurements and for the variation of each inflammatory marker. Results The intra-individual variation (low ICC) was largest for PTX-3 [ICC 0.44; 95% confidence interval (CI): 0.33–0.55], albumin (ICC 0.58; 95% CI: 0.49–0.67) and CRP (ICC 0.59; 95% CI: 0.51–0.68) and lowest for Hcy (ICC 0.81; 95% CI: 0.77–0.86). During follow-up, 88 patients died. Conclusions PTX-3 measurements are less stable and show higher variation within patients than CRP, albumin and Hcy. Persistently elevated PTX-3 levels are associated with high mortality. Moreover, in multivariate logistic regression we found that stable high PTX-3 adds to the mortality risk, even after inclusion of clinical factors and the three other biomarkers. The associations of decreasing albumin levels as well as low Hcy levels with worse outcome reflect protein-energy wasting. PMID:25852911

  2. Relationship between homocysteine and intraocular pressure in men and women

    PubMed Central

    Leibovitzh, Haim; Cohen, Eytan; levi, Amos; Kramer, Michal; Shochat, Tzippy; Goldberg, Elad; Krause, Ilan

    2016-01-01

    Abstract The relationship between homocysteine levels and glaucoma has been questioned in previous studies without conclusive results. In the current study, we assessed the relationship between homocysteine levels and intraocular pressure which is one of the main factors in the development of glaucoma in men and women. A retrospective cross-sectional analysis of a database from a screening center in Israel which assessed 11,850 subjects, within an age range 20 to 80 years. The relationship between homocysteine and intraocular pressure has been investigated by comparing intraocular pressure in subjects with elevated and normal homocysteine and by comparing homocysteine levels in subjects with elevated and normal intraocular pressure. In addition, we compared the levels of homocysteine in subjects with and without a confirmed diagnosis of glaucoma. The mean IOP (±SD) in subjects with normal homocysteine levels(≤15 μmol/L) was 13.2 ± 2.3 mm Hg and 13.4 ± 2.4 mm Hg in those with high homocysteine levels (>15 μmol/L) (P < 0.008, 95% confidence interval [CI] 0.3–0.09).Nonetheless, after multivariate adjustment for age, gender, vitamin B12, and folic acid statistical significance was no longer demonstrated (P = 0.37). Mean homocysteine levels (±SD) in subjects with normal intraocular pressure of ≤ 21 mm Hg was 11.7 ± 5.5 μmol/L and 12.09 ± 3.43 μmol/L in those with elevated intraocular pressure (P = 0.4, 95%CI 1.1–1.8). Mean homocysteine levels (±SD) in subjects with glaucoma were 11.2 ± 3.5 μmol/L compared to 11.7 ± 5.5 μmol/L in subjects without glaucoma and normal intraocular pressure ≤ 21 mm Hg (P = 0.4, 95% CI 1.2–2.1). The current study displays no clinical correlation between the homocysteine level and the intraocular pressure. Homocysteine may not be used as a predictive parameter to recognize those subjects prone to develop elevated intraocular pressure. PMID:27661027

  3. Lack of embryotoxicity of homocysteine thiolactone in mouse embryos in vitro.

    PubMed

    Hansen, D K; Grafton, T F; Melnyk, S; James, S J

    2001-01-01

    Recent work from humans and chick embryos has suggested that homocysteine may play a role in producing neural tube defects (NTDs). In an effort to determine if homocysteine is able to produce NTDs in mammalian embryos, mouse embryos were explanted on GD 8 and cultured for 44 h. When either homocysteine or homocysteine thiolactone was added to the culture medium, treated embryos developed as well as controls and had closed neural tubes. Homocysteine thiolactone was also microinjected into the amniotic sac of mouse embryos. Again, development proceeded normally with no significant increase in the number of embryos with open neural tubes at the end of the culture period. HPLC analysis of embryonic thiols 24 h after microinjection revealed a significant increase in embryonic cystathionine levels. These data suggest that homocysteine does not produce NTDs in mouse embryos cultured in vitro and that early organogenesis-stage embryos are able to metabolize homocysteine.

  4. Genome-wide association study of homocysteine levels in Filipinos provides evidence for CPS1 in women and a stronger MTHFR effect in young adults

    PubMed Central

    Lange, Leslie A.; Croteau-Chonka, Damien C.; Marvelle, Amanda F.; Qin, Li; Gaulton, Kyle J.; Kuzawa, Christopher W.; McDade, Thomas W.; Wang, Yunfei; Li, Yun; Levy, Shawn; Borja, Judith B.; Lange, Ethan M.; Adair, Linda S.; Mohlke, Karen L.

    2010-01-01

    Plasma homocysteine (Hcy) level is associated with cardiovascular disease and may play an etiologic role in vascular damage, a precursor for atherosclerosis. We performed a genome-wide association study for Hcy in 1786 unrelated Filipino women from the Cebu Longitudinal Health and Nutrition Survey (CLHNS). The most strongly associated single-nucleotide polymorphism (SNP) (rs7422339, P = 4.7 × 10−13) encodes Thr1405Asn in the gene CPS1 and explained 3.0% of variation in the Hcy level. The widely studied MTHFR C677T SNP (rs1801133) was also highly significant (P = 8.7 × 10−10) and explained 1.6% of the trait variation. We also genotyped these two SNPs in 1679 CLHNS young adult offspring. The MTHFR C677T SNP was strongly associated with Hcy (P = 1.9 × 10−26) and explained ∼5.1% of the variation in the offspring. In contrast, the CPS1 variant was significant only in females (P = 0.11 in all; P = 0.0087 in females). Combined analysis of all samples confirmed that the MTHFR variant was more strongly associated with Hcy in the offspring (interaction P = 1.2 × 10−5). Furthermore, although there was evidence for a positive synergistic effect between the CPS1 and MTHFR SNPs in the offspring (interaction P = 0.0046), there was no significant evidence for an interaction in the mothers (P = 0.55). These data confirm a recent finding that CPS1 is a locus influencing Hcy levels in women and suggest that genetic effects on Hcy may differ across developmental stages. PMID:20154341

  5. High intake of folic acid or complex of B vitamins provides anti-Parkinsonism effect: no role for serum level of homocysteine.

    PubMed

    Haghdoost-Yazdi, Hashem; Fraidouni, Negin; Faraji, Ayda; Jahanihashemi, Hassan; Sarookhani, Mohammad

    2012-08-01

    Several lines of evidence show that homocysteine (Hcy) levels are increased in blood and CSF of patients with Parkinson's disease. B vitamins are necessary for Hcy metabolism and their deficiencies cause hyperhomocysteinemia and neurodegeneration. In present study, effect of B vitamin supplementation on the severity of 6-hydroxydopamine (6-OHDA)-induced Parkinsonism was investigated. Rats were nourished with B vitamin supplements from 1 month before of stereotaxic injection of 6-OHDA to the end of experiments. Total serum Hcy was measured at the end of experiments to identify its association with Parkinsonism. Both rotational and rotarod tests revealed that supplementation of folic acid, in a dose dependent manner, attenuates severity of Parkinsonism. Supplement of B complex also had beneficial effect and improved motor performance in rotarod test and decreased biased swings in elevated body swing test but had no effect on the apomorphine-induced rotational behavior. Supplement of B(6) attenuated rotational behavior but had no effect on the rotarod performance and swinging behavior. Supplement of B(12) or combination of folic acid with B(6) and B(12) had no effect on the behavioral symptoms of Parkinsonism. Except one group, the levels of Hcy in other vitamin B treated groups were near to that in control group. Surprisingly, Hcy in group of rats that received high intake of folic acid was significantly higher than that in control group. Our results indicate that high intake of folic acid or B complex provides anti-Parkinsonism effect but it is not mediated by lowering plasma Hcy.

  6. Fibrinogen stability under surfactant interaction.

    PubMed

    Hassan, Natalia; Barbosa, Leandro R S; Itri, Rosangela; Ruso, Juan M

    2011-10-01

    Differential scanning calorimetry (DSC), circular dichroism (CD), difference spectroscopy (UV-vis), Raman spectroscopy, and small-angle X-ray scattering (SAXS) measurements have been performed in the present work to provide a quantitatively comprehensive physicochemical description of the complexation between bovine fibrinogen and the sodium perfluorooctanoate, sodium octanoate, and sodium dodecanoate in glycine buffer (pH 8.5). It has been found that sodium octanoate and dodecanoate act as fibrinogen destabilizer. Meanwhile, sodium perfluorooctanoate acts as a structure stabilizer at low molar concentration and as a destabilizer at high molar concentration. Fibrinogen's secondary structure is affected by all three studied surfactants (decrease in α-helix and an increase in β-sheet content) to a different extent. DSC and UV-vis revealed the existence of intermediate states in the thermal unfolding process of fibrinogen. In addition, SAXS data analysis showed that pure fibrinogen adopts a paired-dimer structure in solution. Such a structure is unaltered by sodium octanoate and perfluoroctanoate. However, interaction of sodium dodecanoate with the fibrinogen affects the protein conformation leading to a complex formation. Taken together, all results evidence that both surfactant hydrophobicity and tail length mediate the fibrinogen stability upon interaction.

  7. Effects of bromocriptine mesylate on homocysteine and high-sensitivity C-reactive protein levels in patients with type-2 diabetes mellitus

    PubMed Central

    Niafar, Mitra; Pourafkari, Leili; Shahsavarinia, Kavus; Milanchian, Nushin; Niafar, Farhad; Nader, Nader D.

    2016-01-01

    Introduction: Quick release bromocriptine (BROM-QR), currently approved for glycemic control, reduces the risk of cardiovascular events in adults with type-2 diabetes mellitus (T2DM). This study evaluates the effect of BROM-QR on homocysteine (HOMC) and high sensitive C-reactive protein (hs-CRP), the biochemical markers of coronary atherosclerosis/inflammation, in patients with uncontrolled T2DM. Methods: In this non-randomized, before-and-after clinical trial, patients with uncontrolled T2DM on stable doses of two oral hypoglycemic agents received BROM-QR for 6 months. The change in serum concentrations of HOMC was the primary endpoint. Anthropometric measurements such as body mass index (BMI) and waist circumference were measured at the baseline and at the completion of treatment along with fasting plasma glucose (FPG), HbA1c, total cholesterol, triglyceride, creatinine and hs-CRP. Multivariate regression analysis was performed to identify factors associated with changes in the levels of HOMC. Results: In 64 patients (46 completed 6 months of treatment), age was 55±7 years and the duration of T2DM was 8.0 ± 4.4 years. On enrollment, mean HbA1c, FPG, hs-CRP and HOMC levels were 9.0± 1.3 percent, 184 ± 42 mg/dL, 3.8± 3.4 mg/dl and 10.8 ± 6.2 micromole/L; respectively. Mean decrease of 0.7 ± 1.1 percent for HbA1c (P = 0.001) and 22 ± 44 mg/dL for FPG was observed (P = 0.002). HOMC levels decreased to 8.5 ± 5.2 micromole/L (P = 0.011) while hs-CRP levels remained unchanged at 3.7 ± 2.9 mg/dL (P = 0.835). Conclusion: While HOMC and HbA1c levels decreased significantly after 6 months of treatment with BROM-QR in patients with T2DM, serum levels of hs-CRP, total cholesterol and triglyceride did not significantly change. PMID:27069561

  8. Elevated plasma homocysteine is associated with increased brain atrophy rates in older subjects with mild hypertension.

    PubMed

    Narayan, Sunil K; Firbank, Michael J; Saxby, Brian K; Stansby, Gerard; Hansrani, Monica; O'Brien, John T; Ford, Gary A

    2011-01-01

    We determined using serial MR imaging whether raised plasma homocysteine levels are associated with increased brain atrophy, white matter lesion (WML) progression or incidence of silent brain infarcts (SBIs) in older hypertensive subjects. Brain atrophy rates (0.58 ± 0.48% per year, mean ± SD) were significantly correlated with homocysteine (β = 0.46, p = 0.001 homocysteine; β = 0.44, p = 0.007 homocysteine/folate/B12 models) but not with folate or B12 levels. Progression of WML (0.08 ± 0.16%) was not associated with homocysteine level (B = 0.01, p = 0.29). New SBIs were uncommon. In older hypertensive individuals, plasma homocysteine levels are associated with increased rates of whole-brain atrophy but not WML progression.

  9. Surface properties of fibrinogen and fibrin.

    PubMed

    van Oss, C J

    1990-08-01

    By contact angle measurements on layers of fibrinogen and fibrin, it can be shown that the transformation from fibrinogen to fibrin is accompanied by a change in surface properties from very hydrophilic (fibrinogen) to moderately but definitely hydrophobic (fibrin). It is also shown that, contrary to serum albumin and gamma globulin, fibrinogen does not become more hydrophobic upon drying.

  10. A Protein Extract from Chicken Reduces Plasma Homocysteine in Rats

    PubMed Central

    Lysne, Vegard; Bjørndal, Bodil; Vik, Rita; Nordrehaug, Jan Erik; Skorve, Jon; Nygård, Ottar; Berge, Rolf K.

    2015-01-01

    The present study aimed to evaluate effects of a water-soluble protein fraction of chicken (CP), with a low methionine/glycine ratio, on plasma homocysteine and metabolites related to homocysteine metabolism. Male Wistar rats were fed either a control diet with 20% w/w casein as the protein source, or an experimental diet where 6, 14 or 20% w/w of the casein was replaced with the same amount of CP for four weeks. Rats fed CP had reduced plasma total homocysteine level and markedly increased levels of the choline pathway metabolites betaine, dimethylglycine, sarcosine, glycine and serine, as well as the transsulfuration pathway metabolites cystathionine and cysteine. Hepatic mRNA level of enzymes involved in homocysteine remethylation, methionine synthase and betaine-homocysteine S-methyltransferase, were unchanged, whereas cystathionine gamma-lyase of the transsulfuration pathway was increased in the CP treated rats. Plasma concentrations of vitamin B2, folate, cobalamin, and the B-6 catabolite pyridoxic acid were increased in the 20% CP-treated rats. In conclusion, the CP diet was associated with lower plasma homocysteine concentration and higher levels of serine, choline oxidation and transsulfuration metabolites compared to a casein diet. The status of related B-vitamins was also affected by CP. PMID:26053618

  11. Fibrinogen up-regulates the expression of monocyte chemoattractant protein 1 in human saphenous vein endothelial cells.

    PubMed Central

    Harley, S L; Powell, J T

    1999-01-01

    High concentrations of fibrinogen in plasma have been associated with an increased risk of saphenous vein graft pathology. We have investigated the ability of fibrinogen to up-regulate the expression of monocyte chemoattractant protein 1 (MCP-1) in cultured human saphenous vein endothelial cells (HSVEC) isolated from saphenous vein. Increasing concentrations of fibrinogen (0-4 microM) stimulated a 20-fold increase in MCP-1 secretion within 4 h. Incubation of HSVEC with 2 microM fibrinogen for 4 h also caused a 2-fold increase in the MCP-1-to-glyceraldehyde-3-phosphate dehydrogenase mRNA ratio. The fibrinogen-mediated MCP-1 secretion fell to basal levels after preincubation of HSVEC with the complex of fibrinogen fragments D and E but remained unchanged after preincubation of HSVEC with either fibrinogen fragment E, s-ICAM-1 or the pentapeptide GRGDV. In contrast, fibrinogen fragment D acted as a potent inhibitor of fibrinogen-mediated MCP-1 secretion. Labelled fibrinogen fragment D bound to HSVEC with a K(d) of 6.5 microM. These findings indicate that fibrinogen, at physiological concentrations, uses an epitope on the fibrinogen D domain to bind to a receptor on HSVEC to up-regulate MCP-1 expression and secretion. This receptor seems to be distinct from intercellular adhesion molecule 1 and the integrins previously recognized as fibrinogen receptors. PMID:10417339

  12. Homocystein as a Risk Factor for Developing Complications in Chronic Renal Failure

    PubMed Central

    Jakovljevic, Biljana; Gasic, Branislav; Kovacevic, Pedja; Rajkovaca, Zvezdana; Kovacevic, Tijana

    2015-01-01

    Aim: Cardiovascular diseases are leading cause of death in patients with chronic renal failure. The aim of our study was to establish connection between levels of homocysteine and traditional and nontraditional risk factors for developing cardiovascular diseases in dialysis and pre dialysis patients. Methods: We included 33 pre dialysis (23 in stage three and 10 in stage four of chronic kidney disease) and 43 patients receiving hemodialysis longer than six months. Besides standard laboratory parameters, levels of homocysteine and blood pressure were measured in all patients. Glomerular filtration rate was measured in pre dialysis patients and dialysis quality parameters in dialysis patients. Results: Homocysteine levels were elevated in all patients (19±5.42mmol/l). The connection between homocysteine levels and other cardiovascular diseases risk factors was not established in pre dialysis patients. In patients treated with hemodialysis we found negative correlation between homocysteine levels and patients’ age (p<0.05) and positive correlation between homocysteine levels and length of dialysis (p<0.01) as well as between homocysteine and anemia parameters (erythrocytes, hemoglobin), (p<0.01). Homocysteine and LDL (and total cholesterol) were in negative correlation (p<0.01). Conclusion: Homocysteine, as one of nontraditional cardiovascular diseases risk factors, is elevated in all patients with chronic renal failure and it’s positive correlation with some other risk factors was found. PMID:26005384

  13. Homocysteine and Cognitive Performance in Elders with Self-Neglect

    NASA Technical Reports Server (NTRS)

    Burnett, J.; Smith, S.M.; Aung, K.; Dyer, C.

    2009-01-01

    Elevated plasma homocysteine has been associated with altered cognitive performance in older adults. Elders referred to Adult Protective Services (APS) for self-neglect have been reported to have elevated plasma homocysteine levels and to suffer from cognitive impairment. This study assesses the association, if any, between plasma homocysteine and cognitive performance among elders with self-neglect. Methods: Sixty-five community-living adults, 65 years of age and older, reported to Adult Protective Services for self-neglect and 55 matched controls (matched for age, ethnicity, gender and socio-economic status) consented and participated in this study. The research team conducted in-home comprehensive geriatric assessments which included the mini-mental state exam (MMSE), the 15-item geriatric depression scale (GDS), the Wolf-Klein Clock Drawing Tests (CDT) and a comprehensive nutritional biochemistry panel, which included plasma homocysteine. Student s t tests and Pearson correlations were conducted to assess for bivariate associations. Results: Elders with self-neglect had significantly higher plasma homocysteine levels (M=12.68umol/L, sd=4.4) compared to the controls (M=10.40umol/L, sd=3.61;t=3.21, df=127, p=.002). There were no statistically significant associations between cognitive performance and plasma homocysteine in the self-neglect group, however there was a significant correlation between plasma homocysteine and the CDT among the controls (r=-.296, p=.022). Conclusion: Mean plasma homocysteine levels were significantly higher in elders with self-neglect, however, they do not appear to be related to cognitive performance, indicating that cognitive impairment in elder self-neglect involve mechanisms other than hyperhomocysteinemia. These findings warrant further investigation

  14. Laboratory and Genetic Investigation of Mutations Accounting for Congenital Fibrinogen Disorders.

    PubMed

    Neerman-Arbez, Marguerite; de Moerloose, Philippe; Casini, Alessandro

    2016-06-01

    Congenital fibrinogen disorders are classified into two types of plasma fibrinogen defects: type I (quantitative fibrinogen deficiencies), that is, hypofibrinogenemia or afibrinogenemia, in which there are low or absent plasma fibrinogen antigen levels, respectively, and type II (qualitative fibrinogen deficiencies), that is, dysfibrinogenemia or hypodysfibrinogenemia, in which there are normal or reduced antigen levels associated with disproportionately low functional activity. These disorders are caused by mutations in the three fibrinogen-encoding genes FGA, FGB, and FGG. Afibrinogenemia is associated with mild to severe bleeding, whereas hypofibrinogenemia is often asymptomatic. For these quantitative disorders, the majority of mutations prevent protein production. However, in some cases, missense or late-truncating nonsense mutations allow synthesis of the mutant fibrinogen chain, but intracellular fibrinogen assembly and/or secretion are impaired. Qualitative fibrinogen disorders are associated with bleeding, thrombosis, or both thrombosis and bleeding, but many dysfibrinogenemias are asymptomatic. The majority of cases are caused by heterozygous missense mutations. Here, we review the laboratory and genetic diagnosis of fibrinogen gene anomalies with an updated discussion of causative mutations identified.

  15. Analysis of the safety and pharmacodynamics of human fibrinogen concentrate in animals

    SciTech Connect

    Beyerle, Andrea; Nolte, Marc W.; Solomon, Cristina; Herzog, Eva; Dickneite, Gerhard

    2014-10-01

    Fibrinogen, a soluble 340 kDa plasma glycoprotein, is critical in achieving and maintaining hemostasis. Reduced fibrinogen levels are associated with an increased risk of bleeding and recent research has investigated the efficacy of fibrinogen concentrate for controlling perioperative bleeding. European guidelines on the management of perioperative bleeding recommend the use of fibrinogen concentrate if significant bleeding is accompanied by plasma fibrinogen levels less than 1.5–2.0 g/l. Plasma-derived human fibrinogen concentrate has been available for therapeutic use since 1956. The overall aim of the comprehensive series of non-clinical investigations presented was to evaluate i) the pharmacodynamic and pharmacokinetic characteristics and ii) the safety and tolerability profile of human fibrinogen concentrate Haemocomplettan P® (RiaSTAP®). Pharmacodynamic characteristics were assessed in rabbits, pharmacokinetic parameters were determined in rabbits and rats and a safety pharmacology study was performed in beagle dogs. Additional toxicology tests included: single-dose toxicity tests in mice and rats; local tolerance tests in rabbits; and neoantigenicity tests in rabbits and guinea pigs following the introduction of pasteurization in the manufacturing process. Human fibrinogen concentrate was shown to be pharmacodynamically active in rabbits and dogs and well tolerated, with no adverse events and no influence on circulation, respiration or hematological parameters in rabbits, mice, rats and dogs. In these non-clinical investigations, human fibrinogen concentrate showed a good safety profile. This data adds to the safety information available to date, strengthening the current body of knowledge regarding this hemostatic agent. - Highlights: • A comprehensive series of pre-clinical investigations of human fibrinogen concentrate. • Human fibrinogen concentrate was shown to be pharmacodynamically active. • Human fibrinogen concentrate was well tolerated

  16. The Independent and Joint Association of Blood Pressure, Serum Total Homocysteine, and Fasting Serum Glucose Levels With Brachial-Ankle Pulse Wave Velocity in Chinese Hypertensive Adults.

    PubMed

    Liu, Xiaoyun; Sun, Ningling; Yu, Tao; Fan, Fangfang; Zheng, Meili; Qian, Geng; Wang, Binyan; Wang, Yu; Tang, Genfu; Li, Jianping; Qin, Xianhui; Hou, Fanfan; Xu, Xiping; Yang, Xinchun; Chen, Yundai; Wang, Xiaobin; Huo, Yong

    2016-09-28

    This study aimed to investigate the independent and joint association of blood pressure (BP), homocysteine (Hcy), and fasting blood glucose (FBG) levels with brachial-ankle pulse wave velocity (baPWV, a measure of arterial stiffness) in Chinese hypertensive adults.The analyses included 3967 participants whose BP, Hcy, FBG, and baPWV were measured along with other covariates. Systolic BP (SBP) was analyzed as 3 categories (SBP < 160 mmHg; 160 to 179 mmHg; ≥ 180 mmHg); Hcy as 3 categories (< 10 μmol/L; 10 to 14.9 μmol/L; ≥ 15.0 μmol/L) and FBG: normal (FBG < 5.6 mmol/L), impaired (5.6 mmol/L ≤ FBG < 7.0 mmol/L), and diabetes mellitus (FBG ≥ 7.0 mmol/L). We performed linear regression analyses to evaluate their associations with baPWV with adjustment for covariables.When analyzed individually, BP, Hcy, and FBG were each associated with baPWV. When BP and FBG were analyzed jointly, the highest baPWV value (mean ± SD: 2227 ± 466 cm/s) was observed in participants with FBG ≥ 7.0 mmol/L and SBP ≥ 180 mmHg (β = 432.5, P < 0.001), and the lowest baPWV value (mean ± SD: 1692 ± 289 cm/s) was seen in participants with NFG and SBP < 160 mmHg. When Hcy and FBG were analyzed jointly, the highest baPWV value (2072 ± 480 cm/s) was observed in participants with FBG ≥ 7.0 mmol/L and Hcy ≥ 15.0 μmol/L (β = 167.6, P < 0.001), while the lowest baPWV value (mean ± SD: 1773 ± 334 cm/s) was observed in participants with NFG and Hcy < 10 μmol/L.In Chinese hypertensive adults, SBP, Hcy, and FBG are individually and jointly associated with baPWV.Our findings underscore the importance of identifying individuals with multiple risk factors of baPWV including high SBP, FBG, and Hcy.

  17. Role of plasma homocysteine levels and MTHFR polymorphisms on IQ scores in children and young adults with epilepsy treated with antiepileptic drugs.

    PubMed

    Di Rosa, Gabriella; Lenzo, Patrizia; Parisi, Eleonora; Neri, Milena; Guerrera, Silvia; Nicotera, Antonio; Alibrandi, Angela; Germanò, Eva; Caccamo, Daniela; Spanò, Maria; Tortorella, Gaetano

    2013-12-01

    Homocysteine (Hcy) is a sulfur-containing amino acid involved in methionine metabolism. High plasma total Hcy (tHcy) has been quite frequently reported in patients with epilepsy treated with antiepileptic drugs (AEDs) mainly related to plasma folate reduction induced by AEDs themselves. The role of C677T and A1298C polymorphisms of methylenetetrahydrofolate reductase gene (MTHFR) on the increase of plasma tHcy in patients with epilepsy taking AEDs is still controversial. Cognitive impairment may be associated with epilepsy either as the result of the epileptic syndrome per se or as a side effect induced by the AEDs. High plasma tHcy levels were associated with lower cognitive performances in patients affected by Alzheimer's disease and mild cognitive impairment and in healthy elderly. We searched for a correlation between plasma tHcy levels with the intelligence quotient (IQ) scores in a population of children and young adults with epilepsy treated with old and/or newer AEDs. The study group encompassed 179 patients (92 M, 51.5%) followed at our Unit of Child Neuropsychiatry and aged between 4 and 25years (mean+SD: 14.03±4.25). The inclusion criteria included the following: 1) diagnosis of epilepsy of "unknown cause" (cryptogenic) according to the ILAE classification, 2) age older than 3years, 3) stabilized antiepileptic treatment for at least 6months, and 4) clinical records of cognitive tests, plasma tHcy value, and results of MTHFR polymorphisms. Patients' mean tHcy value was 9.71±3.13μM/L (tHcy<9μM/L as our laboratory cutoff in nonepileptic controls). The mean TIQ score was 85.22 (SD±24.12); the mean VIQ score was 86.32 (SD±20.86); and the mean PIQ score was 86.94 (SD±21.51). C677T and A1298C MTHFR polymorphisms were detected in 74/92 (80%) examined patients and distributed into the following: CT (22.3%), TT (14.9%), CC (10.3%) for C677T, AC (16%), CC (1.1%), and AA (30.3%) for A1298C. Plasma tHcy levels were not significantly related to the IQ scores

  18. The Assembly of Nonadhesive Fibrinogen Matrices Depends on the αC Regions of the Fibrinogen Molecule*

    PubMed Central

    Yermolenko, Ivan S.; Gorkun, Oleg V.; Fuhrmann, Alexander; Podolnikova, Nataly P.; Lishko, Valeryi K.; Oshkadyerov, Stanislav P.; Lord, Susan T.; Ros, Robert; Ugarova, Tatiana P.

    2012-01-01

    Adsorption of fibrinogen on fibrin clots and other surfaces strongly reduces integrin-mediated adhesion of platelets and leukocytes with implications for the surface-mediated control of thrombus growth and blood compatibility of biomaterials. The underlying mechanism of this process is surface-induced aggregation of fibrinogen, resulting in the assembly of a nanoscale multilayered matrix. The matrix is extensible, which makes it incapable of transducing strong mechanical forces via cellular integrins, resulting in insufficient intracellular signaling and weak cell adhesion. To determine the mechanism of the multilayer formation, the physical and adhesive properties of fibrinogen matrices prepared from human plasma fibrinogen (hFg), recombinant normal (rFg), and fibrinogen with the truncated αC regions (FgAα251) were compared. Using atomic force microscopy and force spectroscopy, we show that whereas hFg and rFg generated the matrices with a thickness of ∼8 nm consisting of 7–8 molecular layers, the deposition of FgAα251 was terminated at two layers, indicating that the αC regions are essential for the multilayer formation. The extensibility of the matrix prepared from FgAα251 was 2-fold lower than that formed from hFg and rFg. In agreement with previous findings that cell adhesion inversely correlates with the extensibility of the fibrinogen matrix, the less extensible FgAα251 matrix and matrices generated from human fibrinogen variants lacking the αC regions supported sustained adhesion of leukocytes and platelets. The persistent adhesiveness of matrices formed from fibrinogen derivatives without the αC regions may have implications for conditions in which elevated levels of these molecules are found, including vascular pathologies, diabetes, thrombolytic therapy, and dysfibrinogenemia. PMID:23086938

  19. Plasma Homocysteine is Not Related to the Severity of Microangiopathy in Secondary Raynaud Phenomenon

    PubMed Central

    Jacomella, Vincenzo; Wasila, Monika; Husmann, Marc; Gitzelmann, Gabriela; Meier, Thomas; Amann-Vesti, Beatrice

    2011-01-01

    Introduction: The role of elevated homocysteine in primary and secondary Raynaud phenomenon (RP) and in patients with atherosclerosis has been reported controversially. In secondary RP due to connective tissue disease specific alterations of nailfold capillaries might be present. An association between these microvascular changes and homocysteine has been suggested. Aim: The aim of this study was to determine whether homocysteine level differs between patients with primary and secondary RP and to test the hypothesis that homocysteine or other cardiovascular risk factors are associated with specific features of microangiopathy in secondary RP. Patients and Methods Eighty-one consecutive patients with RP referred for vascular assessment were studied by nailfold capillaroscopy. Homocysteine, C-reactive protein and cholesterol were measured and other cardiovascular risk factors and comorbidities assessed. Results: Homocysteine, C-reactive-protein and cholesterol levels did not differ between patients with primary (n=60) and secondary RP (n=21). Likewise, no differences in the prevalence of cardiovascular risk factors and comorbidities were found. In secondary RP no correlation was found between microvascular involvement and homocysteine or C-reactive protein. Conclusion: Plasma homocysteine is not different in patients with either primary or secondary RP and is therefore not a marker for the distinction of these diseases. The extent of microvascular involvement in secondary RP does not correlate with plasma homocysteine. PMID:22216066

  20. B Vitamins, Homocysteine and Bone Health

    PubMed Central

    Fratoni, Valentina; Brandi, Maria Luisa

    2015-01-01

    Nutrition is one of the most important modifiable factors involved in the development and maintenance of good bone health. Calcium and Vitamin D have confirmed and established roles in the maintenance of proper bone health. However, other nutritional factors could also be implicated. This review will explore the emerging evidence of the supporting role of certain B Vitamins as modifiable factors associated with bone health. Individuals with high levels of homocysteine (hcy) exhibit reduced bone mineral density (BMD), alteration in microarchitecture and increased bone fragility. The pathophysiology caused by high serum homocysteine is not completely clear regarding fractures, but it may involve factors, such as bone mineral density, bone turnover, bone blood flow and collagen cross-linking. It is uncertain whether supplementation with B Vitamins, such as folate, Vitamin B1, and Vitamin B6, could decrease hip fracture incidence, but the results of further clinical trials should be awaited before a conclusion is drawn. PMID:25830943

  1. B vitamins, homocysteine and bone health.

    PubMed

    Fratoni, Valentina; Brandi, Maria Luisa

    2015-03-30

    Nutrition is one of the most important modifiable factors involved in the development and maintenance of good bone health. Calcium and Vitamin D have confirmed and established roles in the maintenance of proper bone health. However, other nutritional factors could also be implicated. This review will explore the emerging evidence of the supporting role of certain B Vitamins as modifiable factors associated with bone health. Individuals with high levels of homocysteine (hcy) exhibit reduced bone mineral density (BMD), alteration in microarchitecture and increased bone fragility. The pathophysiology caused by high serum homocysteine is not completely clear regarding fractures, but it may involve factors, such as bone mineral density, bone turnover, bone blood flow and collagen cross-linking. It is uncertain whether supplementation with B Vitamins, such as folate, Vitamin B1, and Vitamin B6, could decrease hip fracture incidence, but the results of further clinical trials should be awaited before a conclusion is drawn.

  2. Identification of ZNF366 and PTPRD as novel determinants of plasma homocysteine in a family-based genome-wide association study.

    PubMed

    Mälarstig, Anders; Buil, Alfonso; Souto, Juan Carolos; Clarke, Robert; Blanco-Vaca, Francisco; Fontcuberta, Jordi; Peden, John; Andersen, Malin; Silveira, Angela; Barlera, Simona; Seedorf, Udo; Watkins, Hugh; Almasy, Laura; Hamsten, Anders; Soria, José Manuel

    2009-08-13

    Total plasma homocysteine concentration (tHcy) is a biomarker for atherothrombotic disease, but causality remains uncertain. Polymorphisms in the genes involved in methionine metabolism explain only a small fraction of the heritability of tHcy levels. In a genome-wide association study, we examined the genetic determinants of tHcy using a 2-stage design. First, 283 437 single nucleotide polymorphisms (SNPs) were tested for association with tHcy in 387 persons recruited from 21 large Spanish families. Of those, 17 SNPs showed equal or stronger association with tHcy level compared with the MTHFR 677C>T SNP (beta = 0.10, P = .0001). Second, a replication analysis of these 17 SNPs was performed in patients with premature myocardial infarction (n = 1238). Novel associations were found for SNPs near the ZNF366 gene (lead SNP rs7445013; discovery stage: adjusted beta = -0.12, P = 5.30 x 10(-6), replication stage: adjusted beta = -0.13, P = .004) and the PTPRD gene (lead SNP rs973117; discovery stage: adjusted beta = 0.11, P = 5.5 x 10(-6), replication stage: adjusted beta = 0.10, P = .005). These associations were independent of known confounders, including creatinine clearance and plasma fibrinogen concentration. Our findings implicate novel pathways in homocysteine metabolism, and highlight the need for investigation of the associated genes in the etiology of vascular diseases.

  3. Nutritional status influences plasma fibrinogen concentration: evidence from the THUSA survey.

    PubMed

    James, S; Vorster, H H; Venter, C S; Kruger, H S; Nell, T A; Veldman, F J; Ubbink, J B

    2000-06-01

    Nutritional status and risk factors for chronic diseases, including plasma fibrinogen and its determinants, of Africans in the Northwest Province of South Africa, have been studied in a cross-sectional survey. A representative sample of 1854 "apparently healthy" African men and women volunteers aged 15 years and older was recruited from 37 randomly selected sites throughout the Province and stratified for level of urbanisation. Information was collected using validated and culture-sensitive questionnaires. Fasting blood samples were drawn, and all measurements were done with standardised methodology using appropriate equipment, procedures, and controls. Fibrinogen concentration was measured in citrated plasma with the method of Clauss, using the ACL200 automated system and the international fibrinogen standard. The results revealed a population with a high mean plasma fibrinogen (3.17+/-1.10 g/L for HIV-negative men and 3. 64+/-1.12 g/L for HIV-negative women). Factors known to influence plasma fibrinogen, such as age, gender, smoking habit, and physical activity, were also observed in this population. Young rural men and women had the lowest fibrinogen level. Nasal snuff taking and HIV infection did not influence fibrinogen concentration. Multivariate analyses revealed that lower plasma fibrinogen was associated with low to normal body mass index in women, and with dietary intakes compatible with prudent dietary guidelines in men and women (low intakes of animal protein; trans fatty acids and higher intakes of plant protein; dietary fibre, vitamin E, and iron, and a high dietary P/S ratio). Subjects in the higher quartiles of plasma fibrinogen had significantly lower iron, vitamin E, and vitamin B6 (women) status. Increases in fibrinogen were associated with significant increases in serum lipids. Both under- and overnutrition seem to be associated with high plasma fibrinogen. It is concluded that overall nutritional status, possibly in addition to specific

  4. Analysis of the safety and pharmacodynamics of human fibrinogen concentrate in animals.

    PubMed

    Beyerle, Andrea; Nolte, Marc W; Solomon, Cristina; Herzog, Eva; Dickneite, Gerhard

    2014-10-01

    Fibrinogen, a soluble 340kDa plasma glycoprotein, is critical in achieving and maintaining hemostasis. Reduced fibrinogen levels are associated with an increased risk of bleeding and recent research has investigated the efficacy of fibrinogen concentrate for controlling perioperative bleeding. European guidelines on the management of perioperative bleeding recommend the use of fibrinogen concentrate if significant bleeding is accompanied by plasma fibrinogen levels less than 1.5-2.0g/l. Plasma-derived human fibrinogen concentrate has been available for therapeutic use since 1956. The overall aim of the comprehensive series of non-clinical investigations presented was to evaluate i) the pharmacodynamic and pharmacokinetic characteristics and ii) the safety and tolerability profile of human fibrinogen concentrate Haemocomplettan P® (RiaSTAP®). Pharmacodynamic characteristics were assessed in rabbits, pharmacokinetic parameters were determined in rabbits and rats and a safety pharmacology study was performed in beagle dogs. Additional toxicology tests included: single-dose toxicity tests in mice and rats; local tolerance tests in rabbits; and neoantigenicity tests in rabbits and guinea pigs following the introduction of pasteurization in the manufacturing process. Human fibrinogen concentrate was shown to be pharmacodynamically active in rabbits and dogs and well tolerated, with no adverse events and no influence on circulation, respiration or hematological parameters in rabbits, mice, rats and dogs. In these non-clinical investigations, human fibrinogen concentrate showed a good safety profile. This data adds to the safety information available to date, strengthening the current body of knowledge regarding this hemostatic agent.

  5. The methionine-homocysteine cycle and its effects on cognitive diseases.

    PubMed

    Miller, Alan L

    2003-02-01

    Homocysteine, a sulfur-containing amino acid, is a metabolite of the essential amino acid methionine, and exists at a critical biochemical intersection in the methionine cycle - between S-adenosylmethionine, the indispensable ubiquitous methyl donor, and vitamins B12 and folic acid. High blood levels of homocysteine signal a breakdown in this vital process, resulting in far-reaching biochemical and life consequences. The link between homocysteine and cardiovascular disease is well established, and decreasing plasma total homocysteine by providing nutritional cofactors for its metabolism has been shown to reduce the risk of cardiovascular events. Information has been emerging regarding a connection between homocysteine metabolism and cognitive function, from mild cognitive decline (age-related memory loss) to vascular dementia and Alzheimer's disease. Significant deficiencies in the homocysteine re-methylation cofactors cobalamin (B12) and folate, as well as the trans-sulfuration cofactor vitamin B6, are commonly seen in the elderly population, with a resultant increase in homocysteine with advancing age. Hyperhomocysteinemia has been shown to be an independent risk factor for cognitive dysfunction. Indirect and direct vascular damage can be caused by homocysteine, which has been implicated in vascular dementia, with an increased risk of multiple brain infarcts and dementia as homocysteine levels rise. A significant correlation has been found between risk of Alzheimer's disease and high plasma levels of homocysteine, as well as low levels of folic acid, and vitamins B6 and B12. All of these disease associations are thought to be interrelated via increased homocysteine and S-adenosylhomocysteine and subsequent hypomethylation of numerous substances, including DNA and proteins, that render vascular structures and neurons more susceptible to damage and apoptosis. Providing the nutritional cofactors for proper functioning of the methionine cycle may improve methylation

  6. Plasma fibrinogen lever and risk of coronary heart disease among Chinese population: a systematic review and meta-analysis.

    PubMed

    Song, Bin; Shu, Ying; Xu, Yuan Ning; Fu, Ping

    2015-01-01

    Coronary heart disease (CHD) remains the leading causes of death and disability for men and women in most developed countries. It may soon become the leading cause of death in developing countries. Several studies have examined the role of fibrinogen levels in the prediction of atherosclerosis and CHD events. The aim of this study was to explore the effects of plasma fibrinogen levels in Chinese patients with CHD and to examine the relationship of fibrinogen. We performed this meta-analysis of prospective studies of plasma fibrinogen level in relation to CHD risk in electronic database of Medline, EMBase, the Cochrane Library and CNKI (China National Knowledge Infrastructure). Plasma fibrinogen levels were calculated by mean difference with 95% confidence intervals (CI) in patients with CHD and related controls without CHD. The selected 23 studies included 2984 CHD cases and 2279 controls. Our results found that plasma fibrinogen levels of patients were significantly higher than control group (P<0.0001). The predicted odds ratio (OR) for a 1 g/L higher plasma fibrinogen level was 0.94 (95% CI=0.78-1.10). Furthermore, fibrinogen levels were slightly related to age-related CHD patients. The plasma fibrinogen lever was correlated with CHD in the Chinese population, and may be a risk factor and predictor of CHD. Further studies assessing any causal relevance of fibrinogen levels to disease are required.

  7. Venous ulceration, fibrinogen and fibrinolysis.

    PubMed Central

    Leach, R. D.

    1984-01-01

    The effect of long and short-term venous hypertension upon lymph fibrinogen concentrations was studied in an attempt to explain the peri-capillary deposition of fibrin reported in patients with post-phlebitic syndromes. The clearance of radioactive fibrinogen/thrombin clots from the subcutaneous tissues of rats and human volunteers was also studied. Both long- and short-term venous hypertension were found to increase fibrinogen transport across the interstitial space by more than 600%. Not only was there evidence of fibrinolytic activity in the lymph but after long-term venous hypertension alpha 2 antiplasmin activity was also detectable. Skin biopsies from the venous hypertensive ankles showed deposition of interstitial fibrin. The clearance of radioactive fibrinogen/thrombin clots from the subcutaneous tissues of the rat was found to be delayed if the rats were given epsilon amino caproic acid but it could not be increased with stanozolol. In human subjects it was found that patients with lipodermatosclerosis had delayed clot clearance and retarded blood fibrinolytic activity when compared with normal volunteers and patients with uncomplicated varicose veins. The principle cause why tall men are more subject to ulcers than short men, Dr Young conceived to be then length of the column of blood in their veins; which by its pressure, renders the legs less able to recover when hurt by any violence. Images Fig. 1 Fig. 2 Fig. 5 PMID:6742738

  8. Exposure of fibrinogen receptors in human platelets by surface proteolysis with elastase.

    PubMed Central

    Kornecki, E; Ehrlich, Y H; De Mars, D D; Lenox, R H

    1986-01-01

    Human platelets that were preincubated with porcine elastase aggregated spontaneously upon the addition of fibrinogen. Maximal aggregation to fibrinogen was observed with platelets pretreated with an elastase concentration of 111 micrograms/ml, and half-maximal aggregation occurred after treatment with 11 micrograms/ml elastase. Binding of radiolabeled fibrinogen to elastase-treated platelets was specific, saturable, and showed a single class of 48,400 +/- 9,697 fibrinogen-binding sites per platelet with a dissociation constant of 6.30 +/- 1.48 X 10(-7) M. ATP, apyrase, and the stimulators of platelet adenylate cyclase forskolin, prostaglandin E1, prostacyclin, and N6, 2'-O-dibutyryl cyclic AMP did not inhibit the fibrinogen-induced aggregation of elastase-treated platelets. EDTA completely blocked the initiation of aggregation and reversed the fibrinogen-induced aggregation of elastase-treated platelets. Monoclonal and polyclonal antibodies directed against glycoproteins (GP) IIb and IIIa completely blocked the fibrinogen-induced aggregation of elastase-treated platelets. Immunoprecipitates with these antibodies obtained from detergent extracts of surface-radiolabeled, intact, and elastase-treated platelets contained the glycoproteins IIb and IIIa. We conclude that surface proteolysis by low concentrations of elastase can expose fibrinogen-binding sites associated with GPIIb and GPIIIa on the platelet surface, resulting in spontaneous aggregation upon the addition of fibrinogen. These findings may be relevant to hemostatic changes observed in patients with increased levels of circulating elastase. Images PMID:3005363

  9. Biochemical and structural analysis of the interaction between β-amyloid and fibrinogen.

    PubMed

    Zamolodchikov, Daria; Berk-Rauch, Hanna E; Oren, Deena A; Stor, Daniel S; Singh, Pradeep K; Kawasaki, Masanori; Aso, Kazuyoshi; Strickland, Sidney; Ahn, Hyung Jin

    2016-08-25

    The majority of patients with Alzheimer disease (AD) suffer from impaired cerebral circulation. Accumulating evidence suggests that fibrinogen, the main protein component of blood clots, plays an important role in this circulatory dysfunction in AD. Fibrinogen interacts with β-amyloid (Aβ), forming plasmin-resistant abnormal blood clots, and increased fibrin deposition is found in the brains of AD patients and mouse models. In this study, we investigated the biochemical and structural details of the Aβ-fibrinogen interaction. We identified the central region of Aβ42 as the most critical region for the interaction, which can be inhibited by specific antibodies against the central region of Aβ and by naturally occurring p3 peptides, Aβ17-40 and Aβ17-42. X-ray crystallographic analysis revealed that Aβ42 binding to fragment D of fibrinogen induced a structural change in the C-terminal region of the fibrinogen β-chain (β384-393). Furthermore, we identified an additional Aβ-binding site within the αC region of fibrinogen. Aβ binding to this αC region blocked plasmin-mediated fibrin cleavage at this site, resulting in the generation of increased levels of a plasmin-resistant fibrin degradation fragment. Overall, our study elucidates the Aβ-fibrinogen interaction and clarifies the mechanism by which Aβ-fibrinogen binding delays fibrinolysis by plasmin. These results may facilitate the development of effective therapeutics against the Aβ-fibrinogen interaction to treat cerebrovascular abnormalities in AD. PMID:27389717

  10. Recombinant human fibrinogen and sulfation of the. gamma. prime chain

    SciTech Connect

    Farrell, D.H.; Huang, S.; Chung, D.W.; Davie, E.W. ); Mulvihill, E.R. )

    1991-10-01

    Human fibrinogen and the homodimeric {gamma}{prime}-chain-containing variant have been expressed in BHK cells using cDNAs coding for the {alpha},{beta}, and {gamma} (or {gamma}{prime}) chains. The fibrinogens were secreted at levels greater than 4 {mu}g (mg of total cell protein){sup {minus}1}day{sup {minus}1} and were biologically active in clotting assays. Recombinant fibrinogen containing the {gamma}' chain incorporated {sup 35}SO{sub 4} into its chains during biosynthesis, while no incorporation occurred in the protein containing the {gamma} chain. The identity of the sulfated {gamma}{prime} chain was verified by its ability to form dimers during clotting. In addition, carboxypeptidase {Upsilon} digestion of the recombinant fibrinogen containing the {gamma}{prime} chain released 96% of the {sup 35}S label from the sulfated chain, and the radioactive material was identified as tyrosine O-sulfate. These results clarify previous findings of the sulfation of tyrosine in human fibrinogen.

  11. Rapid measurement of fibrinogen concentration in whole blood using a steel ball coagulometer

    PubMed Central

    Schlimp, Christoph J.; Khadem, Anna; Klotz, Anton; Solomon, Cristina; Hochleitner, Gerald; Ponschab, Martin; Redl, Heinz; Schöchl, Herbert

    2015-01-01

    BACKGROUND Fibrinogen plays a key role in hemostasis and is the first coagulation factor to reach critical levels in bleeding patients. Current European guidelines on the management of traumatic or perioperative bleeding recommend fibrinogen supplementation at specific threshold levels. Whole blood viscoelastic tests provide fast evaluation of fibrin deficits. Fast measurement of plasma fibrinogen concentration is not yet available. We investigated a method to rapidly determine whole blood fibrinogen concentration using standard Clauss assays and a steel ball coagulometer and provide an estimate of the “plasma-equivalent” fibrinogen concentration within minutes by adjustment of the measured whole blood fibrinogen concentration with a quickly measureable hemoglobin-derived hematocrit. METHODS The feasibility of this approach was tested with a Clauss assay using multiple porcine fresh blood samples obtained during in vivo bleeding, hemodilution, and after treatment with hemostatic therapy. Two different Clauss assays were then tested using multiple human volunteers’ blood samples diluted in vitro and supplemented with fibrinogen concentrate. Comparative measurements with fibrin-based thromboelastometry tests were performed. RESULTS Regression and Bland-Altman analyses of derived “plasma-equivalent” fibrinogen and measured plasma fibrinogen concentration was excellent in porcine and human blood samples, especially in the ranges relevant to traumatic or perioperative bleeding. CONCLUSION Fast whole blood fibrinogen measurements could be considered as an alternative to plasma fibrinogen measurement for acute bleeding management in trauma and perioperative care settings. Further studies are needed to prove this concept and determine the turnaround times for its clinical application in emergency departments and operating theaters. PMID:25742256

  12. Improved treatment of sudden hearing loss by specific fibrinogen aphaeresis.

    PubMed

    Ullrich, Heidrun; Kleinjung, Tobias; Steffens, Thomas; Jacob, Peter; Schmitz, Gerd; Strutz, Jürgen

    2004-01-01

    The etiology of sudden sensorineural hearing loss is still unclear and is thought to result from disturbances of microcirculation, infectious causes, or autoimmune disorders. So far standard therapy did not show clear improvement over spontaneous remission rate, which is assumed to be about 50% [Nakashima et al., Acta. Otolaryngol. Stockh. 514:14-16, 1994; Schuknecht and Donovan, Arch. Otorhinolaryngol. 243:1-15, 1986; Harris and Sharp, Laryngoscope 100:516-524, 1990; Mayot et al., Clin. Immunol. Immunopath. 68:41-45, 1993; Gussen, Ann. Otol. Rhinol. Laryngol. 85:94-100, 1976]. Elevated blood viscosity due to high fibrinogen levels is supposed to cause decreased cochlear blood flow and thus initiate sudden hearing loss. The specific lowering of fibrinogen immediately decreases plasma viscosity exactly to the desired extent and should lead to improved cochlear blood flow [Suckfüll et al., Acta. Otolaryngol 119:763-766, 1999; Suckfüll, Lancet 360:1811-1817, 2002; Walch et al., Laryngol. Rhino. Otol. 75:641-645, 1996; Suckfüll et al., Otol. Neurotol. 23:309-311, 2002]. In a prospective uncontrolled pilot study on 36 patients with unilateral sudden onset sensorineural hearing loss (SHL) we tried to establish that 1-3 specific fibrinogen aphaereses alone improve recovery of hearing and that it is possible to lower fibrinogen to the target of 80-100 mg/dl without important side effects. Pure tone audiometry was carried out immediately before and after each aphaeresis as well as at 2 and 4 weeks and 6 months after treatment. Sixteen patients recovered spontaneously before undergoing fibrinogen adsorption. All 20 aphaeresis patients improved during immunoadsorption; in 60% of patients auditory thresholds returned to normal after the first immunoadsorption and treatment could be discontinued, in another 20% of patients complete recovery was reached after 4 weeks. The mean plasma fibrinogen concentration of the 20 patients before the first aphaeresis session was 308

  13. Alcohol consumption and plasma homocysteine.

    PubMed

    Sakuta, Hidenari; Suzuki, Takashi

    2005-10-01

    A few reports show that consumption of spirits and of wine correlate with elevated plasma total homocysteine (tHcy), which is associated with the risk of cardiovascular disease. We analyzed the relation between tHcy and current daily ethanol consumption cross-sectionally in middle-aged Japanese men (n = 974, age 51-59 years). Plasma tHcy was positively associated with consumption of whiskey but not with consumption of shochu (Japanese spirits), sake, beer, or wine. Odds ratios of an increase in daily intake of 30 ml ethanol (approximately 1 standard deviation) for hyperhomocysteinemia (>14.0 micromol/l) were 2.58 (95% confidence interval, 1.29-5.14) for whiskey, 1.08 (0.78-1.50) for shochu, 0.99 (0.59-1.66) for sake, 0.98 (0.58-1.63) for beer, and 1.70 (0.31-9.50) for wine in a multivariate logistic regression analysis adjusted for the daily number of cigarettes smoked, physical activity, vegetable consumption, and serum creatinine levels. After inclusion of plasma folate and vitamin B12 in the multivariate analysis model, the association between whiskey ethanol consumption and hyperhomocysteinemia remained significant with odds ratio of 2.79 (1.36-5.72). These results suggest that whiskey consumption correlates with hyperhomocysteinemia independently of plasma folate or vitamin B12 or lifestyle factors in the population studied.

  14. Alcohol consumption and plasma homocysteine.

    PubMed

    Sakuta, Hidenari; Suzuki, Takashi

    2005-10-01

    A few reports show that consumption of spirits and of wine correlate with elevated plasma total homocysteine (tHcy), which is associated with the risk of cardiovascular disease. We analyzed the relation between tHcy and current daily ethanol consumption cross-sectionally in middle-aged Japanese men (n = 974, age 51-59 years). Plasma tHcy was positively associated with consumption of whiskey but not with consumption of shochu (Japanese spirits), sake, beer, or wine. Odds ratios of an increase in daily intake of 30 ml ethanol (approximately 1 standard deviation) for hyperhomocysteinemia (>14.0 micromol/l) were 2.58 (95% confidence interval, 1.29-5.14) for whiskey, 1.08 (0.78-1.50) for shochu, 0.99 (0.59-1.66) for sake, 0.98 (0.58-1.63) for beer, and 1.70 (0.31-9.50) for wine in a multivariate logistic regression analysis adjusted for the daily number of cigarettes smoked, physical activity, vegetable consumption, and serum creatinine levels. After inclusion of plasma folate and vitamin B12 in the multivariate analysis model, the association between whiskey ethanol consumption and hyperhomocysteinemia remained significant with odds ratio of 2.79 (1.36-5.72). These results suggest that whiskey consumption correlates with hyperhomocysteinemia independently of plasma folate or vitamin B12 or lifestyle factors in the population studied. PMID:16584970

  15. [Disturbances of folic acid and homocysteine metabolism in alcohol abuse].

    PubMed

    Cylwik, Bogdan; Chrostek, Lech

    2011-04-01

    Chronic alcohol abuse leads to malnutrition, and thus to the deficiency of many nutrients, including vitamins and trace elements. Most often comes to the deficiency of all vitamins, however because the clinical implications, the most important is folic acid (vitamin B9) deficiency. Biochemical effect of folate deficiency is elevated homocysteine concentration in the blood, named "cholesterol of XXI. century". In the paper, the folate and homocysteine metabolism in alcohol abuse was discussed. Mechanisms of alcohol action on folate homeostasis in the human body have been indicated. Chronic alcohol consumption leads to deficiency of this vitamin due to their dietary inadequacy, intestinal malabsorption, decreased hepatic uptake and increased body excretion, mainly via urine. The decreased concentration of serum folic acid may occur in 80% of alcoholics. The cause of elevated concentrations of homocysteine in the serum of alcohol abusers is also a deficiency of vitamins involved such as vitamin B12 and pyridoxal phosphate. Disturbance of folic acid and homocysteine metabolism in alcohol abusers can lead to serious clinical consequences. Folic acid deficiency leads inter alia to macrocytic and megaloblastic anemia and neurological disorders. Megaloblastic anemia occurs in about half of alcohol abusers with chronic liver diseases. In turn, high level of homocysteine in blood is associated with an inreased risk of cardiovascular diseases. Hyperhomocysteinemia is an independent risk factor that favors the occurrence of acute coronary syndromes in patients with coronary heart disease.

  16. A novel fibrinogen B beta chain frameshift mutation causes congenital afibrinogenaemia.

    PubMed

    Zhang, Jian; Zhao, Xiaojuan; Wang, Zhaoyue; Yu, Ziqiang; Cao, Lijuan; Zhang, Wei; Bai, Xia; Ruan, Changgeng

    2013-07-01

    Congenital afibrinogenaemia is a rare autosomal recessive disorder caused by various mutations within the fibrinogen genes FGA, FGB and FGG. Ins/del mutations in FGB are extremely rare. We report a patient with afibrinogenaemia who suffered from umbilical cord bleeding and repeated bleeding episodes. His plasma fibrinogen levels could not be detected using the Clauss method and immunological methods. Molecular analyses revealed homozygosity in a novel four bases insertion in codon 40 of FGB exon 2 (g. 2833_2834 ins GTTT), which resulted in a truncated 50-residue polypeptide that contained 11 exceptional abnormal residues. In the transient expression experiments, mutant fibrinogen could be detected at higher level than wild-type fibrinogen in COS-7 cell lysates but not in culture media. These results suggest that the homozygous mutation in FGB could be responsible for congenital afibrinogenaemia in this patient. This frameshift mutation could impair fibrinogen assembly and secretion without influencing the protein synthesis.

  17. A study on human serum albumin influence on glycation of fibrinogen

    SciTech Connect

    Kielmas, Martyna; Szewczuk, Zbigniew; Stefanowicz, Piotr

    2013-09-13

    Highlights: •The glycation of fibrinogen was investigated by isotopic labeling method. •The potential glycation sites in fibrinogen were identified. •Human serum albumin (HSA) inhibits the glycation of fibrinogen. •The effect of HSA on fibrinogen glycation is sequence-dependent. -- Abstract: Although in vivo glycation proceeds in complex mixture of proteins, previous studies did not take in consideration the influence of protein–protein interaction on Maillard reaction. The aim of our study was to test the influence of human serum albumin (HSA) on glycation of fibrinogen. The isotopic labeling using [{sup 13}C{sub 6}] glucose combined with LC-MS were applied as tool for identification possible glycation sites in fibrinogen and for evaluation the effect of HSA on the glycation level of selected amino acids in fibrinogen. The obtained data indicate that the addition of HSA protects the fibrinogen from glycation. The level of glycation in presence of HSA is reduced by 30–60% and depends on the location of glycated residue in sequence of protein.

  18. Arf6 arbitrates fibrinogen endocytosis.

    PubMed

    Rondina, Matthew T; Weyrich, Andrew S

    2016-03-17

    In this issue of Blood, in a departure from studies of classic platelet function, Huang et al turn their attention to endocytosis and show that adenosine 5′-diphosphate-ribosylation factor 6 (Arf6) plays a key role in fibrinogen engulfment. Although platelets are known to bind, absorb, and load their granules with plasma proteins, this report is one of the first to explore mechanisms that control endocytosis in this anucleate cell. Huang et al demonstrate that Arf6-dependent endocytosis is restricted to fibrinogen, implying that Arf6 also modulates trafficking of αIIbβ3 integrins in platelets. Consistent with this notion, deletion of Arf6 in platelets enhances spreading on fibrinogen and accelerates clot retraction (see figure). However, activation of surface αIIbβ3 is unaffected, and Arf6 deficiency does not alter thrombosis in vivo. These incongruous results point toward the complexity of anucleate platelets and the need for more detailed studies to understand intracellular trafficking, recycling, and endocytosis in platelets and their precurs

  19. 21 CFR 864.7340 - Fibrinogen determination system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... consists of the instruments, reagents, standards, and controls used to determine the fibrinogen levels in disseminated intravascular coagulation (nonlocalized clotting within the blood vessels) and primary fibrinolysis (the dissolution of fibrin in a blood clot). (b) Classification. Class II (performance standards)....

  20. Ablation of MMP9 gene ameliorates paracellular permeability and fibrinogen-amyloid beta complex formation during hyperhomocysteinemia.

    PubMed

    Muradashvili, Nino; Tyagi, Reeta; Metreveli, Naira; Tyagi, Suresh C; Lominadze, David

    2014-09-01

    Increased blood level of homocysteine (Hcy), called hyperhomocysteinemia (HHcy) accompanies many cognitive disorders including Alzheimer's disease. We hypothesized that HHcy-enhanced cerebrovascular permeability occurs via activation of matrix metalloproteinase-9 (MMP9) and leads to an increased formation of fibrinogen-β-amyloid (Fg-Aβ) complex. Cerebrovascular permeability changes were assessed in C57BL/6J (wild type, WT), cystathionine-β-synthase heterozygote (Cbs+/-, a genetic model of HHcy), MMP9 gene knockout (Mmp9-/-), and Cbs and Mmp9 double knockout (Cbs+/-/Mmp9-/-) mice using a dual-tracer probing method. Expression of vascular endothelial cadherin (VE-cadherin) and Fg-Aβ complex formation was assessed in mouse brain cryosections by immunohistochemistry. Short-term memory of mice was assessed with a novel object recognition test. The cerebrovascular permeability in Cbs+/- mice was increased via mainly the paracellular transport pathway. VE-cadherin expression was the lowest and Fg-Aβ complex formation was the highest along with the diminished short-term memory in Cbs+/- mice. These effects of HHcy were ameliorated in Cbs+/-/Mmp9-/- mice. Thus, HHcy causes activation of MMP9 increasing cerebrovascular permeability by downregulation of VE-cadherin resulting in an enhanced formation of Fg-Aβ complex that can be associated with loss of memory. These data may lead to the identification of new targets for therapeutic intervention that can modulate HHcy-induced cerebrovascular permeability and resultant pathologies. PMID:24865997

  1. [Micromethod for the determination of heat fibrinogen].

    PubMed

    Rogner, G

    1976-01-01

    Description of a micromethod for determining heat fibrinogen where 0.06 to 0.08 ml of citrate plasma are only required. The results are similar to those of the heat fibrinogen method according to SCHULZ, yet they are by 15% below the average values of the Biuret test. The method is particularly suited as a quick orientating determination of fibrinogen for paediatrics and neonatology. A time of 30 minutes approximately is required for it.

  2. Alleviation of hepatic fat accumulation by betaine involves reduction of homocysteine via up-regulation of betaine-homocysteine methyltransferase (BHMT).

    PubMed

    Ahn, Chul Won; Jun, Doo Sung; Na, Jong Deok; Choi, Yeo Jin; Kim, Young Chul

    2016-08-26

    We investigated the anti-lipogenic effect of betaine in rats fed methionine and choline-deficient diet (MCD). Intake of MCD for 3 wk resulted in a significant accumulation of hepatic lipids, which was prevented by betaine supplementation in drinking water (1%). Phosphorylation of AMP-activated protein kinase (AMPK), acetyl-CoA carboxylase (ACC), sterol regulatory element-binding protein-1c (SREBP-1c), and liver kinase B1 (LKB1) was inhibited by MCD intake, and these changes were all inhibited by betaine feeding. Meanwhile, betaine supplementation reversed the reduction of methionine and S-adenosylmethionine (SAM), and the elevation of homocysteine levels in the liver, which could be attributable to the induction of betaine-homocysteine methyltransferase (BHMT) and methionine adenosyltransferase (MAT). Different cell lines were used to clarify the role of homocysteine on activation of the AMPK pathway. Homocysteine treatment decreased pAMPK, pACC, pSREBP-1c and pLKB1 in HepG2 cells. Metformin-induced activation of AMPK was also inhibited by homocysteine. Treatment with hydroxylamine, a cystathionine β-synthase inhibitor, resulted in a reduction of pAMPK, pACC and pSREBP-1c, accompanied by an elevation of intracellular homocysteine. Betaine treatment prevented the homocysteine-induced reduction of pAMPK, pACC, pSREBP-1c and pLKB1 in H4IIE cells, but not in HepG2 cells. Also the elevation of cellular homocysteine and inhibition of protein expression of BHMT were prevented by betaine only in H4IIE cells which express BHMT. The results suggest that the beneficial effect of betaine against hepatic lipid accumulation may be attributed, at least in part, to the depletion of homocysteine via up-regulation of BHMT in hepatocytes. PMID:27320863

  3. Relationship between homocysteine and intraocular pressure in men and women: A population-based study.

    PubMed

    Leibovitzh, Haim; Cohen, Eytan; Levi, Amos; Kramer, Michal; Shochat, Tzippy; Goldberg, Elad; Krause, Ilan

    2016-09-01

    The relationship between homocysteine levels and glaucoma has been questioned in previous studies without conclusive results. In the current study, we assessed the relationship between homocysteine levels and intraocular pressure which is one of the main factors in the development of glaucoma in men and women.A retrospective cross-sectional analysis of a database from a screening center in Israel which assessed 11,850 subjects, within an age range 20 to 80 years. The relationship between homocysteine and intraocular pressure has been investigated by comparing intraocular pressure in subjects with elevated and normal homocysteine and by comparing homocysteine levels in subjects with elevated and normal intraocular pressure. In addition, we compared the levels of homocysteine in subjects with and without a confirmed diagnosis of glaucoma.The mean IOP (±SD) in subjects with normal homocysteine levels(≤15 μmol/L) was 13.2 ± 2.3 mm Hg and 13.4 ± 2.4 mm Hg in those with high homocysteine levels (>15 μmol/L) (P < 0.008, 95% confidence interval [CI] 0.3-0.09).Nonetheless, after multivariate adjustment for age, gender, vitamin B12, and folic acid statistical significance was no longer demonstrated (P = 0.37). Mean homocysteine levels (±SD) in subjects with normal intraocular pressure of ≤ 21 mm Hg was 11.7 ± 5.5 μmol/L and 12.09 ± 3.43 μmol/L in those with elevated intraocular pressure (P = 0.4, 95%CI 1.1-1.8). Mean homocysteine levels (±SD) in subjects with glaucoma were 11.2 ± 3.5 μmol/L compared to 11.7 ± 5.5 μmol/L in subjects without glaucoma and normal intraocular pressure ≤ 21 mm Hg (P = 0.4, 95% CI 1.2-2.1).The current study displays no clinical correlation between the homocysteine level and the intraocular pressure. Homocysteine may not be used as a predictive parameter to recognize those subjects prone to develop elevated intraocular pressure. PMID:27661027

  4. Homocysteine Lowering and Cognition in CKD: The VA Homocysteine Study

    PubMed Central

    Brady, Christopher B.; Gaziano, J. Michael; Cxypoliski, Roberta A.; Guarino, Peter D.; Kaufman, James S.; Warren, Stuart R.; Hartigan, Pamela; Goldfarb, David S.; Jamison, Rex L.

    2009-01-01

    Background Individuals with advanced chronic kidney disease (CKD) and end stage renal disease (ESRD) have high total plasma homocysteine (tHcy) levels, which may be a risk factor for cognitive impairment. Whether treatment with high dose B-vitamins to reduce high tHcy levels improves cognition in persons with kidney disease is unknown. Study Design Randomized controlled trial. Setting & Participants A substudy of 659 patients (mean age 67.3 ± 11.7 years) who participated in a randomized, double-blind, clinical trial, 5 years in duration, conducted in 36 US Department of Veterans Affairs medical centers, of the effect on all-cause mortality of vitamin-induced lowering of plasma tHcy. 236 (35.8%) were treated by dialysis (ESRD) and 423 (64.2%) had a Cockcroft-Gault estimated creatinine clearance ≤ 30 ml/min (advanced CKD). All had high tHcy levels (≥15 μmol/L) at baseline. Cognitive assessments began during the follow up period of the main trial, 3 years after treatment began; participants were subsequently retested one year later to assess cognitive change. Intervention Daily high dose B-vitamin capsule (40 mg of folic acid, 100 mg of vitamin B6, and 2 mg of vitamin B12) or placebo. Outcomes Cognitive function at initial assessment and one year later. Measurements The Telephone Interview of Cognitive Status – modified, supplemented with attention, working memory and executive function tests. Results Initial cognitive function was impaired in approximately 19% of patients, regardless of treatment assignment (vitamin or placebo) or kidney disease status (advanced CKD or ESRD). Treatment reduced tHcy levels by 26.7%. Unadjusted and adjusted analyses showed that treatment did not improve initial cognitive outcomes or affect subsequent cognitive status one year later. Limitations Cognitive assessments began after treatment was initiated; cognitive assessment was limited. Conclusion Treatment with high daily doses of B-vitamins, which reduced tHcy levels, did not

  5. Effect of a Klamath algae product ("AFA-B12") on blood levels of vitamin B12 and homocysteine in vegan subjects: a pilot study.

    PubMed

    Baroni, Luciana; Scoglio, Stefano; Benedetti, Serena; Bonetto, Chiara; Pagliarani, Silvia; Benedetti, Yanina; Rocchi, Marco; Canestrari, Franco

    2009-03-01

    Vitamin B12 is a critical nutrient that is often inadequate in a plant-based (vegan) diet, thus the inclusion of a reliable vitamin B12 source in a vegan diet is recommended as essential. Unfortunately, many natural sources of vitamin B12 have been proven to contain biologically inactive vitamin B12 analogues, inadequate for human supplementation. The aim of this non-randomized open trial was to determine whether supplementation with a natural Klamath algae-based product ("AFA-B12", Aphanizomenon flos-aquae algae plus a proprietary mix of enzymes) could favorably affect the vitamin B12 status of a group of 15 vegan subjects. By assessing blood concentration of vitamin B12, folate, and more importantly homocysteine (Hcy, a reliable marker in vegans of their B12 absorption), the vitamin B12 status of the participants at the end of the 3-month intervention period, while receiving the Klamath-algae supplement (T2), was compared with their vitamin B12 status at the end of the 3-month control period (T1), when they were not receiving any supplement, having stopped taking their usual vitamin B12 supplement at the beginning of the study (T0). Compared to the control period, in the intervention period participants improved their vitamin B12 status, significantly reducing Hcy blood concentration (p=0.003). In conclusion, the Klamath algae product AFA-B12 appears to be, in a preliminary study, an adequate and reliable source of vitamin B12 in humans.

  6. A comparison of the fibrinogen receptor distribution on adherent platelets using both soluble fibrinogen and fibrinogen immobilized on gold beads.

    PubMed

    Estry, D W; Mattson, J C; Mahoney, G J; Oesterle, J R

    1991-04-01

    The distribution of fibrinogen receptors was determined on the surface of adherent platelets using both direct labeling with the ligand fibrinogen which was immobilized on gold particles (Fg-Au) and indirect immunogold (Ig-Au) labeling of bound soluble fibrinogen identified with a rabbit polyclonal anti-fibrinogen antibody. Two distinctly different patterns of labeling were obtained and appeared to depend on whether solid phase fibrinogen (Fg-Au) or soluble phase released fibrinogen were bound to the membrane receptor. The membrane-bound Fg-Au reorganized in patterns that closely mimicked the organization of the underlying cytoskeleton. In approximately 18% of the adherent platelets, Fg-Au was seen in channels or vesicle-like structures lying deep to the platelet surface suggesting internalization into the open canalicular system and/or endocytosis. The labeling pattern obtained when identifying the location of membrane-bound soluble released fibrinogen by Ig-Au was diffuse and lacked the organizational patterns characteristic of Fg-Au. Unlike the Fg-Au probe, early dendritic platelets were heavily labeled by the soluble phase fibrinogen using the Ig-Au technique. Although the label covered the entire exposed platelet membrane in fully spread platelets, labeling over the peripheral web was more dense than that over the intermediate or granulomere zone. The diffuse organization and heavier peripheral distributional pattern of the glycoprotein IIb-IIIa (GP IIb-IIIa) receptor in fixed, adherent platelets, was also seen with the GP IIb-IIIa receptor-specific antibody AP-2. The binding of both the Fg-Au and Ig-Au were inhibited using the tetrapeptide Arg-Gly-Asp-Ser (RGDS) (93% and 98% inhibition, respectively), AP-2 (98% and 97%, respectively) and platelets from patients with Glanzmann's thrombasthenia (GT) (99% and 98%, respectively). The data presented provides the first report that receptor reorganization, following binding of fibrinogen, appears to be related to

  7. Over 50 Years of Fibrinogen Concentrate

    PubMed Central

    Hochleitner, Gerald; Wendt, Michael; Teruya, Alexandre; Spahn, Donat R.

    2015-01-01

    March 2013 represented the 50th anniversary of the first license granted for a fibrinogen concentrate. In this review, we look at the history of bleeding management that led to the development of fibrinogen concentrate, discuss its current use, and consider future developments for this product. PMID:26294722

  8. Homocysteine and its nutritional determinants in two ethnic groups of Slovakia.

    PubMed

    Krajcovicová-Kudlácková, M; Blazícek, P; Ginter, E; Valachicová, M

    2004-12-01

    Determinants of total homocysteine involve demographic (age, sex, ethnic origin), genetic (enzymatic defects of metabolic homocysteine pathways) and acquired factors (deficiency of B-group vitamins, state of health, lifestyle). Plasma levels of total homocysteine and serum levels of vitamin B12, folic acid, vitamin B6 were measured in adult apparently healthy Romany minority subjects (n=119) and compared with those levels in apparently healthy subjects of majority Slovak population (n=146). Mean homocysteine level was similar in both groups (9.92 micromol/l in the Romany vs. 9.61 micromol/l in majority group). Hyperhomocysteinemia was only observed in 3% of both ethnic probands. Vitamin B12 level was equal (301 micromol/l in the Romany and 311 micromol/ in majority group). Deficient levels were found in 4% of the Romany subjects and 9% of the majority subjects. Folic acid level was significantly lower in Romany group (11.3 nmol/l vs. 14.8 nmol/l) with deficiency in 42% of the Romany subjects vs. 28% in the majority subjects. This finding is a consequence of lower consumption of fruit, vegetables, pulses and whole grain products in the Romany group. Vitamin B6 deficiency was found in 68% of the Romany subjects and 40% of majority subjects. This vitamin is homocysteine determinant under excessive methionine intake (overnutrition with predominance of animal protein intake). As was demonstrated in a dietetic questionnaires, the Romany subjects are more frequent consumers of meat and eggs. This nutrition regime should indicate an increased homocysteine level under vitamin B6 deficiency. The results of normal homocysteine levels in the Romany population under condition of higher folic acid and vitamin B6 deficiencies, smoking and higher alcohol consumption may suggest a more effective homocysteine metabolism in relation to different ethnic origin.

  9. Homocysteine Metabolism in Children with Down Syndrome: In Vitro Modulation

    PubMed Central

    Pogribna, Marta; Melnyk, Stepan; Pogribny, Igor; Chango, Abalo; Yi, Ping; James, S. Jill

    2001-01-01

    The gene for cystathionine β-synthase (CBS) is located on chromosome 21 and is overexpressed in children with Down syndrome (DS), or trisomy 21. The dual purpose of the present study was to evaluate the impact of overexpression of the CBS gene on homocysteine metabolism in children with DS and to determine whether the supplementation of trisomy 21 lymphoblasts in vitro with selected nutrients would shift the genetically induced metabolic imbalance. Plasma samples were obtained from 42 children with karyotypically confirmed full trisomy 21 and from 36 normal siblings (mean age 7.4 years). Metabolites involved in homocysteine metabolism were measured and compared to those of normal siblings used as controls. Lymphocyte DNA methylation status was determined as a functional endpoint. The results indicated that plasma levels of homocysteine, methionine, S-adenosylhomocysteine, and S-adenosylmethionine were all significantly decreased in children with DS and that their lymphocyte DNA was hypermethylated relative to that in normal siblings. Plasma levels of cystathionine and cysteine were significantly increased, consistent with an increase in CBS activity. Plasma glutathione levels were significantly reduced in the children with DS and may reflect an increase in oxidative stress due to the overexpression of the superoxide dismutase gene, also located on chromosome 21. The addition of methionine, folinic acid, methyl-B12, thymidine, or dimethylglycine to the cultured trisomy 21 lymphoblastoid cells improved the metabolic profile in vitro. The increased activity of CBS in children with DS significantly alters homocysteine metabolism such that the folate-dependent resynthesis of methionine is compromised. The decreased availability of homocysteine promotes the well-established “folate trap,” creating a functional folate deficiency that may contribute to the metabolic pathology of this complex genetic disorder. PMID:11391481

  10. Three cases of congenital dysfibrinogenemia in unrelated Chinese families: heterozygous missense mutation in fibrinogen alpha chain Argl6His.

    PubMed

    Luo, Meiling; Deng, Donghong; Xiang, Liqun; Cheng, Peng; Liao, Lin; Deng, Xuelian; Yan, Jie; Lin, Faquan

    2016-09-01

    Congenital dysfibrinogenemia (CD) is a qualitative fibrinogen disorder caused by an abnormal fibrinogen molecule structure, leading to dysfunctional blood coagulation. This study describes 3 cases of dysfibrinogenemia identified in the unrelated Chinese pedigrees.Routine coagulation screening tests were performed on the probands and their families. The antigens and functionality of fibrinogen was measured using an immunoturbidimetry assay and the Clauss method, respectively. To identify the genetic mutation responsible for these dysfibrinogens, genomic DNA extracted from the blood was analyzed using PCR amplification and direct sequencing. The presence of the mutant chains was determined using matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectroscopy. Purified plasma fibrinogen of 3 probands was analyzed using SDS-PAGE, fibrinogen clottability, fibrin polymerization, fibrinopeptide release, and scanning electron microscopy (SEM).The 3 probands had a long thrombin time. Levels of functional fibrinogen were found to be very low, while the fibrinogen antigen was within the normal range. DNA sequencing revealed a heterozygous Arg16His substitution in the fibrinogen Aα chain (FGA). The mutant chains were found to be expressed using MALDI-TOF mass spectroscopy. SDS-PAGE did not reveal any difference in the molecular weights of 3 polypeptide chains between normal and abnormal fibrinogens. Fibrinogen clottability showed a slower fibrin clot formation than the healthy control. Fibrin polymerization, after addition of thrombin, showed a prolonged lag phase and decreased final turbidity. The kinetics of fibrinopeptides release revealed a decreased amount of the released fibrinopeptide A. SEM of the patient's fibrin clot was found to be abnormal.Results indicate that the 3 probands with dysfibrinogenemia were caused by mutations of Aα chain Arg16His. Mutation of this fibrinogen induced dysfunction of plasma fibrinogen. PMID:27684817

  11. Deletion of the fibrinogen [correction of fibrogen] alpha-chain gene (FGA) causes congenital afibrogenemia.

    PubMed

    Neerman-Arbez, M; Honsberger, A; Antonarakis, S E; Morris, M A

    1999-01-01

    Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by the complete absence of detectable fibrinogen. Uncontrolled bleeding after birth from the umbilical cord is common, and spontaneous intracerebral bleeding and splenic rupture can occur throughout life. Patients respond well to fibrinogen replacement therapy, either prophylactically or on demand. Because the half-life of infused fibrinogen is essentially normal, the genetic defect is assumed to be at the level of synthesis, but no responsible locus has been identified. Preliminary studies using Southern blotting suggested that no gross structural changes of the fibrinogen genes were present in patients. We report the identification of causative mutations in a nonconsanguineous Swiss family with congenital afibrinogenemia. The four affected male individuals (two brothers and their two first cousins) have homozygous deletions of approximately 11 kb of the fibrinogen alpha-chain gene (FGA). Haplotype data suggest that these deletions occurred separately, on three distinct ancestral chromosomes, implying that the FGA region of the fibrinogen locus is susceptible to deletion by a common mechanism. Furthermore, our results demonstrate that humans, like mice, may be born without the capacity to synthesize functional fibrinogen.

  12. A novel fibrinogen mutation (γ Thr277Arg) causes hereditary hypofibrinogenemia in a Chinese family.

    PubMed

    Zhu, Liqing; Wang, Mingshan; Xie, Haixiao; Jin, Yanhui; Yang, Lihong; Xu, Pengfei

    2013-09-01

    Congenital hypofibrinogenemia is a rare disorder caused by heterozygous mutations in one of the three fibrinogen genes--fibrinogen α-chain (FGA), fibrinogen β-chain (FGB) and fibrinogen γ-chain (FGG)--which code for the Aα, Bβ and γ chains, respectively. In this study, we identified a genetic defect in the FGG underlying the hypofibrinogenemia. The proposita had a prolonged blood clotting time (thrombin time 24.5 s, prothrombin time 16.8 s) and a low level of plasma fibrinogen (0.71 g/l by Clauss method and 0.79 g/l by immunoturbidimetry). DNA screening of the whole fibrinogen gene revealed a heterozygous GC mutation at nucleotide 7482 in her FGG gene. Her father and her half-brother are also heterozygous for this mutation. This mutation contributes to Thr277 → Arg in the γ chain of fibrinogen. To the best of our knowledge, this is the first report of such a mutation that is associated with hypofibrinogenemia.

  13. The Effects of Acute Exercise and Exercise Training on Plasma Homocysteine: A Meta-Analysis

    PubMed Central

    Deminice, Rafael; Ribeiro, Diogo Farias; Frajacomo, Fernando Tadeu Trevisan

    2016-01-01

    Background Although studies have demonstrated that physical exercise alters homocysteine levels in the blood, meta-analyses of the effects of acute exercise and exercise training on homocysteine blood concentration have not been performed, especially regarding the duration and intensity of exercise, which could affect homocysteine levels differently. Objective The aim of this meta-analysis was to ascertain the effects of acute exercise and exercise training on homocysteine levels in the blood. Method A review was conducted according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses using the online databases PubMed, SPORTDiscus, and SciELO to identify relevant studies published through June 2015. Review Manager was used to calculate the effect size of acute exercise and exercise training using the change in Hcy plasmaserum concentration from baseline to post-acute exercise and trained vs. sedentary control groups, respectively. Weighted mean differences were calculated using random effect models. Results Given the abundance of studies, acute exercise trials were divided into two subgroups according to exercise volume and intensity, whereas the effects of exercise training were analyzed together. Overall, 22 studies with a total of 520 participants indicated increased plasma homocysteine concentration after acute exercise (1.18 μmol/L, 95% CI: 0.71 to 1.65, p < .01). Results of a subgroup analysis indicated that either long-term exercise of low-to-moderate intensity (1.39 μmol/L, 95% CI: 0.9 to 1.89, p < .01) or short-term exercise of high intensity (0.83 μmol/L, 95% CI: 0.19 to 1.40, p < .01) elevated homocysteine levels in the blood. Increased homocysteine induced by exercise was significantly associated with volume of exercise, but not intensity. By contrast, resistance training reduced plasma homocysteine concentration (-1.53 μmol/L, 95% CI: -2.77 to -0.28, p = .02), though aerobic training did not. The cumulative

  14. Bacteriophage lysin mediates the binding of streptococcus mitis to human platelets through interaction with fibrinogen.

    PubMed

    Seo, Ho Seong; Xiong, Yan Q; Mitchell, Jennifer; Seepersaud, Ravin; Bayer, Arnold S; Sullam, Paul M

    2010-01-01

    The binding of bacteria to human platelets is a likely central mechanism in the pathogenesis of infective endocarditis. We have previously found that platelet binding by Streptococcus mitis SF100 is mediated by surface components encoded by a lysogenic bacteriophage, SM1. We now demonstrate that SM1-encoded lysin contributes to platelet binding via its direct interaction with fibrinogen. Far Western blotting of platelets revealed that fibrinogen was the major membrane-associated protein bound by lysin. Analysis of lysin binding with purified fibrinogen in vitro confirmed that these proteins could bind directly, and that this interaction was both saturable and inhibitable. Lysin bound both the Aalpha and Bbeta chains of fibrinogen, but not the gamma subunit. Binding of lysin to the Bbeta chain was further localized to a region within the fibrinogen D fragment. Disruption of the SF100 lysin gene resulted in an 83+/-3.1% reduction (mean +/- SD) in binding to immobilized fibrinogen by this mutant strain (PS1006). Preincubation of this isogenic mutant with purified lysin restored fibrinogen binding to wild type levels. When tested in a co-infection model of endocarditis, loss of lysin expression resulted in a significant reduction in virulence, as measured by achievable bacterial densities (CFU/g) within vegetations, kidneys, and spleens. These results indicate that bacteriophage-encoded lysin is a multifunctional protein, representing a new class of fibrinogen-binding proteins. Lysin appears to be cell wall-associated through its interaction with choline. Once on the bacterial surface, lysin can bind fibrinogen directly, which appears to be an important interaction for the pathogenesis of endocarditis. PMID:20714354

  15. Bacteriophage lysin mediates the binding of streptococcus mitis to human platelets through interaction with fibrinogen.

    PubMed

    Seo, Ho Seong; Xiong, Yan Q; Mitchell, Jennifer; Seepersaud, Ravin; Bayer, Arnold S; Sullam, Paul M

    2010-08-12

    The binding of bacteria to human platelets is a likely central mechanism in the pathogenesis of infective endocarditis. We have previously found that platelet binding by Streptococcus mitis SF100 is mediated by surface components encoded by a lysogenic bacteriophage, SM1. We now demonstrate that SM1-encoded lysin contributes to platelet binding via its direct interaction with fibrinogen. Far Western blotting of platelets revealed that fibrinogen was the major membrane-associated protein bound by lysin. Analysis of lysin binding with purified fibrinogen in vitro confirmed that these proteins could bind directly, and that this interaction was both saturable and inhibitable. Lysin bound both the Aalpha and Bbeta chains of fibrinogen, but not the gamma subunit. Binding of lysin to the Bbeta chain was further localized to a region within the fibrinogen D fragment. Disruption of the SF100 lysin gene resulted in an 83+/-3.1% reduction (mean +/- SD) in binding to immobilized fibrinogen by this mutant strain (PS1006). Preincubation of this isogenic mutant with purified lysin restored fibrinogen binding to wild type levels. When tested in a co-infection model of endocarditis, loss of lysin expression resulted in a significant reduction in virulence, as measured by achievable bacterial densities (CFU/g) within vegetations, kidneys, and spleens. These results indicate that bacteriophage-encoded lysin is a multifunctional protein, representing a new class of fibrinogen-binding proteins. Lysin appears to be cell wall-associated through its interaction with choline. Once on the bacterial surface, lysin can bind fibrinogen directly, which appears to be an important interaction for the pathogenesis of endocarditis.

  16. Bacteriophage Lysin Mediates the Binding of Streptococcus mitis to Human Platelets through Interaction with Fibrinogen

    PubMed Central

    Seo, Ho Seong; Xiong, Yan Q.; Mitchell, Jennifer; Seepersaud, Ravin; Bayer, Arnold S.; Sullam, Paul M.

    2010-01-01

    The binding of bacteria to human platelets is a likely central mechanism in the pathogenesis of infective endocarditis. We have previously found that platelet binding by Streptococcus mitis SF100 is mediated by surface components encoded by a lysogenic bacteriophage, SM1. We now demonstrate that SM1-encoded lysin contributes to platelet binding via its direct interaction with fibrinogen. Far Western blotting of platelets revealed that fibrinogen was the major membrane-associated protein bound by lysin. Analysis of lysin binding with purified fibrinogen in vitro confirmed that these proteins could bind directly, and that this interaction was both saturable and inhibitable. Lysin bound both the Aα and Bβ chains of fibrinogen, but not the γ subunit. Binding of lysin to the Bβ chain was further localized to a region within the fibrinogen D fragment. Disruption of the SF100 lysin gene resulted in an 83±3.1% reduction (mean ± SD) in binding to immobilized fibrinogen by this mutant strain (PS1006). Preincubation of this isogenic mutant with purified lysin restored fibrinogen binding to wild type levels. When tested in a co-infection model of endocarditis, loss of lysin expression resulted in a significant reduction in virulence, as measured by achievable bacterial densities (CFU/g) within vegetations, kidneys, and spleens. These results indicate that bacteriophage-encoded lysin is a multifunctional protein, representing a new class of fibrinogen-binding proteins. Lysin appears to be cell wall-associated through its interaction with choline. Once on the bacterial surface, lysin can bind fibrinogen directly, which appears to be an important interaction for the pathogenesis of endocarditis. PMID:20714354

  17. [Fibrinogen. An old hemostatic protein with a new function: non-invasive marker of subclinical atherosclerosis].

    PubMed

    Páramo, José A; Rodríguez, José A; Orbe, Josune

    2005-05-28

    The formation of a fibrin clot is one of the key events in atherothrombotic vascular diseases, such as myocardial infarction, ischemic stroke and peripheral arterial disease. Fibrin is formed from a circulating precursor, fibrinogen, by the action of thrombin. Both genetic and environmental factors are important determinants of the circulating fibrinogen levels. Epidemiologic studies have demonstrated a role for this hemostatic protein in the prediction of cardiovascular disease. As an acute-phase reactant, fibrinogen is also a marker of inflammation. Likewise, recent studies from our group have shown that increased fibrinogen levels represent a marker of subclinical atherosclerosis, likely to be useful in the identification of asymptomatic subjects at risk for cardiovascular disease.

  18. Comparison of Protein N-Homocysteinylation in Rat Plasma under Elevated Homocysteine Using a Specific Chemical Labeling Method.

    PubMed

    Zang, Tianzhu; Pottenplackel, Ligi Paul; Handy, Diane E; Loscalzo, Joseph; Dai, Shujia; Deth, Richard C; Zhou, Zhaohui Sunny; Ma, Jisheng

    2016-01-01

    Elevated blood concentrations of homocysteine have been well established as a risk factor for cardiovascular diseases and neuropsychiatric diseases, yet the etiologic relationship of homocysteine to these disorders remains poorly understood. Protein N-homocysteinylation has been hypothesized as a contributing factor; however, it has not been examined globally owing to the lack of suitable detection methods. We recently developed a selective chemical method to label N-homocysteinylated proteins with a biotin-aldehyde tag followed by Western blotting analysis, which was further optimized in this study. We then investigated the variation of protein N-homocysteinylation in plasma from rats on a vitamin B12 deficient diet. Elevated "total homocysteine" concentrations were determined in rats with a vitamin B12 deficient diet. Correspondingly, overall levels of plasma protein N-homocysteinylation displayed an increased trend, and furthermore, more pronounced and statistically significant changes (e.g., 1.8-fold, p-value: 0.03) were observed for some individual protein bands. Our results suggest that, as expected, a general metabolic correlation exists between "total homocysteine" and N-homocysteinylation, although other factors are involved in homocysteine/homocysteine thiolactone metabolism, such as the transsulfuration of homocysteine by cystathionine β-synthase or the hydrolysis of homocysteine thiolactone by paraoxonase 1 (PON1), may play more significant or direct roles in determining the level of N-homocysteinylation. PMID:27617989

  19. Sensitivity of staurosporine-induced differentiated RGC-5 cells to homocysteine

    PubMed Central

    Ganapathy, Preethi S.; Dun, Ying; Ha, Yonju; Duplantier, Jennifer; Allen, John Bradley; Farooq, Amina; Bozard, B. Renee; Smith, Sylvia B.

    2011-01-01

    PURPOSE Homocysteine is implicated in ganglion cell death associated with glaucoma. To understand mechanisms of homocysteine-induced cell death, we analyzed the sensitivity of the RGC-5 cell line, differentiated using staurosporine, to physiologically-relevant levels of the excitotoxic amino acid homocysteine. METHODS RGC-5 cells were differentiated 24 h using 316 nM staurosporine and tested for expression of Thy 1.2 via immunodetection, RT-PCR and immunoblotting. The sensitivity of staurosporine-differentiated RGC-5 cells to physiological levels of homocysteine (50, 100, 250 µM) and to high levels of homocysteine (1 mM), glutamate (1 mM) and oxidative stress (25 µM:10 mU/ml xanthine:xanthine oxidase) was assessed by TUNEL assay and by immunodetection of cleaved caspase-3. The sensitivity of undifferentiated RGC-5 cells to high (1, 5, and 10 mM) homocysteine was also examined. RESULTS Undifferentiated RGC-5 cells express Thy 1.2 mRNA and protein. Staurosporine-differentiated RGC-5 cells extend neurite processes and express Thy 1.2 after 24 h differentiation; they express NF-L after 1 and 3 days differentiation. Treatment of staurosporine-differentiated RGC-5 cells with 50, 100 or 250µM homocysteine did not alter neurite processes nor induce cell death (detected by TUNEL and active caspase-3) to a level greater than that observed in non-homocysteine-treated, staurosporine-differentiated cells. The 1 mM dosage of homocysteine in staurosporine-differentiated RGC-5 cells also did not induce cell death above control levels, although 18 h treatment of non-differentiated RGC-5 cells with 5 mM homocysteine decreased survival by 50%. CONCLUSIONS RGC-5 cells differentiated for 24 h with 316 nM staurosporine project robust neurite processes and are positive for ganglion cell markers consistent with a more neuronal phenotype than non- staurosporine-differentiated RGC-5 cells. However, concentrations of homocysteine known to induce ganglion cell death in vivo and in primary

  20. NADPH oxidase 4 regulates homocysteine metabolism and protects against acetaminophen-induced liver damage in mice

    PubMed Central

    Murray, Thomas V.A.; Dong, Xuebin; Sawyer, Greta J.; Caldwell, Anna; Halket, John; Sherwood, Roy; Quaglia, Alberto; Dew, Tracy; Anilkumar, Narayana; Burr, Simon; Mistry, Rajesh K.; Martin, Daniel; Schröder, Katrin; Brandes, Ralf P.; Hughes, Robin D.; Shah, Ajay M.; Brewer, Alison C.

    2015-01-01

    Glutathione is the major intracellular redox buffer in the liver and is critical for hepatic detoxification of xenobiotics and other environmental toxins. Hepatic glutathione is also a major systemic store for other organs and thus impacts on pathologies such as Alzheimer's disease, Sickle Cell Anaemia and chronic diseases associated with aging. Glutathione levels are determined in part by the availability of cysteine, generated from homocysteine through the transsulfuration pathway. The partitioning of homocysteine between remethylation and transsulfuration pathways is known to be subject to redox-dependent regulation, but the underlying mechanisms are not known. An association between plasma Hcy and a single nucleotide polymorphism within the NADPH oxidase 4 locus led us to investigate the involvement of this reactive oxygen species- generating enzyme in homocysteine metabolism. Here we demonstrate that NADPH oxidase 4 ablation in mice results in increased flux of homocysteine through the betaine-dependent remethylation pathway to methionine, catalysed by betaine-homocysteine-methyltransferase within the liver. As a consequence NADPH oxidase 4-null mice display significantly lowered plasma homocysteine and the flux of homocysteine through the transsulfuration pathway is reduced, resulting in lower hepatic cysteine and glutathione levels. Mice deficient in NADPH oxidase 4 had markedly increased susceptibility to acetaminophen-induced hepatic injury which could be corrected by administration of N-acetyl cysteine. We thus conclude that under physiological conditions, NADPH oxidase 4-derived reactive oxygen species is a regulator of the partitioning of the metabolic flux of homocysteine, which impacts upon hepatic cysteine and glutathione levels and thereby upon defence against environmental toxins. PMID:26472193

  1. Dietary determinants of plasma homocysteine concentrations.

    PubMed

    Verhoef, Petra; de Groot, Lisette C P G M

    2005-05-01

    Severe hyperhomocysteinemia is typically caused by rare enzymatic defects or by renal failure. In contrast, mild to moderate hyperhomocysteinemia chiefly results from suboptimal status of nutritional factors involved in homocysteine metabolism. Low dietary intake of folate is the most important nutritional cause of elevated homocysteine (tHcy) concentrations. Folic acid is more effective than dietary folate in lowering tHcy concentrations, and a daily dose of 400 mug of folic acid is the minimum daily dose associated with the maximum tHcy-lowering effect ( approximately 20-25% reduction). Mean fasting tHcy concentrations have dropped substantially in populations with mandatory folic acid fortification, and other B-vitamins, such as vitamin B (12), are important determinants of tHcy levels in this setting. Vitamins B (2) and B (6) have little influence on fasting tHcy concentrations, although the former may be relevant in individuals with the MTHFR 677 TT-genotype, and the latter may improve tHcy catabolism in elderly individuals. Betaine and choline can lower fasting tHcy concentrations to a similar extent as folic acid, particularly in the setting of a high intake of methionine. Consumption of tea and coffee increase tHcy concentrations by up to 20%. A high-protein meal also increases tHcy, but these changes are transient, and levels return to normal after an overnight fast. Serine and cystine also influence the methionine-induced postprandial rise in tHcy concentrations. In conclusion, alteration in dietary intake or use of folic acid supplements can substantially lower tHcy concentrations. However, it is not known whether lowering tHcy levels can reduce the risk of cardiovascular disease or cognitive decline or prevent pregnancy complications or osteoporosis. PMID:16047264

  2. Competitions between fibrinogen with its degradation products for interactions with the platelet-fibrinogen receptor

    SciTech Connect

    Thorsen, L.I.; Brosstad, F.; Gogstad, G.; Sletten, K.; Solum, N.O.

    1986-12-01

    Direct binding of /sup 125/-I-labelled plasmic and CNBr-derived fibrin (ogen) fragments (pre-X, X, Y, D, Degta, Efg, E1, N-DSK, N-dsk) to gel-filtered platelets was compared to their ability to support or inhibit ADP-induced aggregation, and to compete with fibrinogen for binding to ADP-stimulated platelets. Pre-X was the only fragment that supported aggregation. All fragments tested except for E derived from fibrinogen (Efg) and Degta bound specifically to the platelets and inhibited ADP-induced aggregation in the presence of fibrinogen. Competitive binding studies with fibrinogen and fragments labelled with different isotopes of iodine, or inhibition of binding of labelled fibrinogen with unlabelled fragments showed that all of the fragments except Efg and Degta were able to compete with fibrinogen for binding. When simultaneous binding of N-dsk and fibrinogen was studied, an increased binding of both ligands was observed probably due to complex formation. The results fully agree with previous findings of binding to immunoprecipitated glycoprotein IIb-IIIa after crossed immunoelectrophoresis. We conclude that the fibrinogen molecule contains at least six sequences responsible for platelet interaction, two in the E domain and two in each of the C-terminal parts of the fibrinogen molecule.

  3. [Interaction of fibrinogen with magnetite nanoparticles].

    PubMed

    Bychkova, A V; Sorokina, O N; Kovarskiĭ, A L; Shapiro, A B; Leonova, V B; Rozenfel'd, M A

    2010-01-01

    The interaction between fibrinogen and magnetite nanoparticles in solution has been studied by the methods of spin labeling, ferromagnetic resonance, dynamic and Rayleigh light scattering. It was shown that protein molecules adsorb on the surface of nanoparticles to form multilayer protein covers. The number of molecules adsorbed on one nanoparticle amounts to approximately 65 and the thickness of the adsorption layer amounts to approximately 27 nm. Separate nanoparticles with fibrinogen covers (clusters) form aggregates due to interactions of the end D-domains of fibrinogen. Under the influence of direct magnetic field, nanoparticles with adsorbed proteins form linear aggregates parallel to force lines. It was shown that the rate of protein coagulation during the formation of fibrin gel under the action of thrombin on fibrinogen decreases approximately 2 times in the presence of magnetite nanoparticles, and the magnitude of the average fiber mass-length ratio grows.

  4. Mice expressing a mutant form of fibrinogen that cannot support fibrin formation exhibit compromised antimicrobial host defense

    PubMed Central

    Prasad, Joni M.; Gorkun, Oleg V.; Raghu, Harini; Thornton, Sherry; Mullins, Eric S.; Palumbo, Joseph S.; Ko, Ya-Ping; Höök, Magnus; David, Tovo; Coughlin, Shaun R.; Degen, Jay L.

    2015-01-01

    Fibrin(ogen) is central to hemostasis and thrombosis and also contributes to multiple physiologic and pathologic processes beyond coagulation. However, the precise contribution of soluble fibrinogen vs insoluble fibrin matrices to vascular integrity, tissue repair, inflammation, and disease has been undefined and unapproachable. To establish the means to distinguish fibrinogen- and fibrin-dependent processes in vivo, FibAEK mice were generated that carry normal levels of circulating fibrinogen but lack the capacity for fibrin polymer formation due to a germ-line mutation in the Aα chain thrombin cleavage site. Homozygous FibAEK mice developed to term and exhibited postnatal survival superior to that of fibrinogen-deficient mice. Unlike fibrinogen-deficient mice, platelet-rich plasma from FibAEK mice supported normal platelet aggregation in vitro, highlighting that fibrinogenAEK retains the functional capacity to support interactions with platelets. Thrombin failed to release fibrinopeptide-A from fibrinogenAEK and failed to induce polymer formation with FibAEK plasma or purified fibrinogenAEK in 37°C mixtures regardless of incubation time. FibAEK mice displayed both an absence of fibrin polymer formation following liver injury, as assessed by electron microscopy, and a failure to generate stable occlusive thrombi following FeCl3 injury of carotid arteries. FibAEK mice exhibited a profound impediment in Staphylococcus aureus clearance following intraperitoneal infection similar to fibrinogen-deficient mice, yet FibAEK mice displayed a significant infection dose-dependent survival advantage over fibrinogen-deficient mice following peritonitis challenge. Collectively, these findings establish for the first time that fibrin polymer is the molecular form critical for antimicrobial mechanisms while simultaneously highlighting biologically meaningful contributions and functions of the soluble molecule. PMID:26228483

  5. Mice expressing a mutant form of fibrinogen that cannot support fibrin formation exhibit compromised antimicrobial host defense.

    PubMed

    Prasad, Joni M; Gorkun, Oleg V; Raghu, Harini; Thornton, Sherry; Mullins, Eric S; Palumbo, Joseph S; Ko, Ya-Ping; Höök, Magnus; David, Tovo; Coughlin, Shaun R; Degen, Jay L; Flick, Matthew J

    2015-10-22

    Fibrin(ogen) is central to hemostasis and thrombosis and also contributes to multiple physiologic and pathologic processes beyond coagulation. However, the precise contribution of soluble fibrinogen vs insoluble fibrin matrices to vascular integrity, tissue repair, inflammation, and disease has been undefined and unapproachable. To establish the means to distinguish fibrinogen- and fibrin-dependent processes in vivo, Fib(AEK) mice were generated that carry normal levels of circulating fibrinogen but lack the capacity for fibrin polymer formation due to a germ-line mutation in the Aα chain thrombin cleavage site. Homozygous Fib(AEK) mice developed to term and exhibited postnatal survival superior to that of fibrinogen-deficient mice. Unlike fibrinogen-deficient mice, platelet-rich plasma from Fib(AEK) mice supported normal platelet aggregation in vitro, highlighting that fibrinogen(AEK) retains the functional capacity to support interactions with platelets. Thrombin failed to release fibrinopeptide-A from fibrinogen(AEK) and failed to induce polymer formation with Fib(AEK) plasma or purified fibrinogen(AEK) in 37°C mixtures regardless of incubation time. Fib(AEK) mice displayed both an absence of fibrin polymer formation following liver injury, as assessed by electron microscopy, and a failure to generate stable occlusive thrombi following FeCl3 injury of carotid arteries. Fib(AEK) mice exhibited a profound impediment in Staphylococcus aureus clearance following intraperitoneal infection similar to fibrinogen-deficient mice, yet Fib(AEK) mice displayed a significant infection dose-dependent survival advantage over fibrinogen-deficient mice following peritonitis challenge. Collectively, these findings establish for the first time that fibrin polymer is the molecular form critical for antimicrobial mechanisms while simultaneously highlighting biologically meaningful contributions and functions of the soluble molecule. PMID:26228483

  6. Associations between Serum 25-hydroxyvitamin D and Lipids, Lipoprotein Cholesterols, and Homocysteine

    PubMed Central

    Glueck, Charles J.; Jetty, Vybhav; Rothschild, Matan; Duhon, Gregory; Shah, Parth; Prince, Marloe; Lee, Kevin; Goldenberg, Michael; Kumar, Ashwin; Goldenberg, Naila; Wang, Ping

    2016-01-01

    Background: Serum 25(OH) vitamin D levels are inversely associated with cardiovascular disease (CVD) mortality, mediated in part by independent positive relationships with high-density lipoprotein cholesterol (HDLC) and inverse relationships with low-density lipoprotein cholesterol (LDLC), triglyceride, and homocysteine. Aims: In this study, we assessed relationships between fasting serum vitamin D and lipids, lipoprotein cholesterols, and homocysteine. Materials and Methods: We studied 1534 patients sequentially referred to our center from 2007 to 2016. Fasting serum total 25(OH) vitamin D, plasma cholesterol, triglyceride, HDLC, LDLC, and homocysteine were measured. Stepwise regression models were used with total cholesterol, triglyceride, HDLC, LDLC, and homocysteine as dependent variables and explanatory variables age, race, gender, body mass index (BMI), and serum vitamin D levels. Relationships between quintiles of serum vitamin D and triglycerides, HDLC, LDLC, and homocysteine were assessed after covariance adjusting for age, race, gender, and BMI. Results: Fasting serum vitamin D was positively correlated with age, HDLC, and White race, and was inversely correlated with BMI, total and LDL cholesterol, triglyceride, and fasting serum homocysteine (P ≤ 0.0001 for all). Serum vitamin D was a significant independent inverse explanatory variable for total cholesterol, triglyceride, and LDL cholesterol, and accounted for the largest amount of variance in serum total cholesterol (partial R2 =3.6%), triglyceride (partial R2 =3.1%), and LDLC (partial R2 =2.9%) (P < 0.0001 for all). Serum vitamin D was a significant positive explanatory variable for HDLC (partial R2 = 1.4%, P < 0.0001), and a significant inverse explanatory variable for homocysteine (partial R2 = 6.0–12.6%). Conclusions: In hyperlipidemic patients, serum vitamin D was a significant independent inverse determinant of total cholesterol, LDLC, triglyceride, and homocysteine, and a significant

  7. High homocysteine induces betaine depletion.

    PubMed

    Imbard, Apolline; Benoist, Jean-François; Esse, Ruben; Gupta, Sapna; Lebon, Sophie; de Vriese, An S; de Baulny, Helene Ogier; Kruger, Warren; Schiff, Manuel; Blom, Henk J

    2015-04-28

    Betaine is the substrate of the liver- and kidney-specific betaine-homocysteine (Hcy) methyltransferase (BHMT), an alternate pathway for Hcy remethylation. We hypothesized that BHMT is a major pathway for homocysteine removal in cases of hyperhomocysteinaemia (HHcy). Therefore, we measured betaine in plasma and tissues from patients and animal models of HHcy of genetic and acquired cause. Plasma was collected from patients presenting HHcy without any Hcy interfering treatment. Plasma and tissues were collected from rat models of HHcy induced by diet and from a mouse model of cystathionine β-synthase (CBS) deficiency. S-adenosyl-methionine (AdoMet), S-adenosyl-homocysteine (AdoHcy), methionine, betaine and dimethylglycine (DMG) were quantified by ESI-LC-MS/MS. mRNA expression was quantified using quantitative real-time (QRT)-PCR. For all patients with diverse causes of HHcy, plasma betaine concentrations were below the normal values of our laboratory. In the diet-induced HHcy rat model, betaine was decreased in all tissues analysed (liver, brain, heart). In the mouse CBS deficiency model, betaine was decreased in plasma, liver, heart and brain, but was conserved in kidney. Surprisingly, BHMT expression and activity was decreased in liver. However, in kidney, BHMT and SLC6A12 expression was increased in CBS-deficient mice. Chronic HHcy, irrespective of its cause, induces betaine depletion in plasma and tissues (liver, brain and heart), indicating a global decrease in the body betaine pool. In kidney, betaine concentrations were not affected, possibly due to overexpression of the betaine transporter SLC6A12 where betaine may be conserved because of its crucial role as an osmolyte.

  8. The model homologue of the partially defective human 5,10-methylenetetrahydrofolate reductase, considered as a risk factor for stroke due to increased homocysteine level, can be protected and reactivated by heat shock proteins.

    PubMed

    Grabowski, Michał; Banecki, Bogdan; Kadziński, Leszek; Jakóbkiewicz-Banecka, Joanna; Gabig-Cimińska, Magdalena; Węgrzyn, Alicja; Węgrzyn, Grzegorz; Banecka-Majkutewicz, Zyta

    2016-10-01

    The A222 V substitution in the human MTHFR gene product (5,10-methylenetetrahydrofolate reductase) is responsible for a decreased activity of this enzyme. This may cause an increased homocysteine level, considered as a risk factor for arteriosclerosis and stroke. The bacterial homologue of the human enzyme, MetF, has been found to be a useful model in genetic and biochemical studies. The similarity of Escherichia coli MetF and human MTHFR proteins is so high that particular mutations in the corresponding human gene can be reflected by the bacterial mutants. For example, the A222 V substitution in MTHFR (caused by the C667T substitution in the MTHFR gene) can be ascribed to the A117 V substitution in MetF. Here, it is reported that a temperature-sensitive MetF117 (A117 V) protein can be partially protected from a thermal inactivation by the heat shock proteins from the Hsp70/100 systems. Moreover, activity of the thermally denatured enzyme can be partially restored by the same heat shock proteins. High temperature protein G (HtpG) had no effect on MetF117 activity in both experimental systems. The presented results indicate that functions of heat shock proteins may be required for maintenance of the MetF117 function. This may have implications for the mechanisms of arteriosclerosis and stroke, especially in the light of previous findings that the A222 V MTHFR polymorphism may be a risk factor for stroke, as well as recently published results which demonstrated the increased levels of antibodies against heat shock proteins in stroke patients. PMID:27234992

  9. DACH-LIGA homocystein (german, austrian and swiss homocysteine society): consensus paper on the rational clinical use of homocysteine, folic acid and B-vitamins in cardiovascular and thrombotic diseases: guidelines and recommendations.

    PubMed

    Stanger, Olaf; Herrmann, Wolfgang; Pietrzik, Klaus; Fowler, Brian; Geisel, Jürgen; Dierkes, Jutta; Weger, Martin

    2003-11-01

    About half of all deaths are due to cardiovascular disease and its complications. The economic burden on society and the healthcare system from cardiovascular disability, complications, and treatments is huge and getting larger in the rapidly aging populations of developed countries. As conventional risk factors fail to account for part of the cases, homocysteine, a "new" risk factor, is being viewed with mounting interest. Homocysteine is a sulfur-containing intermediate product in the normal metabolism of methionine, an essential amino acid. Folic acid, vitamin B12, and vitamin B6 deficiencies and reduced enzyme activities inhibit the breakdown of homocysteine, thus increasing the intracellular homocysteine concentration. Numerous retrospective and prospective studies have consistently found an independent relationship between mild hyperhomocysteinemia and cardiovascular disease or all-cause mortality. Starting at a plasma homocysteine concentration of approximately 10 micromol/l, the risk increase follows a linear dose-response relationship with no specific threshold level. Hyperhomocysteinemia as an independent risk factor for cardiovascular disease is thought to be responsible for about 10% of total risk. Elevated plasma homocysteine levels (>12 micromol/l; moderate hyperhomocysteinemia) are considered cytotoxic and are found in 5 to 10% of the general population and in up to 40% of patients with vascular disease. Additional risk factors (smoking, arterial hypertension, diabetes, and hyperlipidemia) may additively or, by interacting with homocysteine, synergistically (and hence over-proportionally) increase overall risk. Hyperhomocysteinemia is associated with alterations in vascular morphology, loss of endothelial anti-thrombotic function, and induction of a procoagulant environment. Most known forms of damage or injury are due to homocysteine-mediated oxidative stress. Especially when acting as direct or indirect antagonists of cofactors and enzyme

  10. [A correlation study on homocysteine metabolism in pregnant women and neural tube defects in urban and rural areas].

    PubMed

    Zhan, S; Hu, Y; Li, L

    1997-07-01

    Serum levels of homocysteine, folic acid and vitamin B12 in pregnant women in urban and rural areas were compared to study the relationship between homocysteine metabolism and neural tube defects. Four hundred and eleven serum specimens were sampled randomly from a serum bank for women with early pregnancy in Beijing area, 195 from urban and 216 from rural. Their levels of homocysteine were determined by high performance liquid chromatography combined with electrochemical methods, and those of folic acid and vitamin B12 by radioimmunoassay. Results showed that level of homocysteine was significantly higher in rural pregnant women than that in urban, with 9.31 mumol/L and 5.73 mumol/L, respectively, level of vitamin B12 was lower in rural than that in urban women, with 210.09 pmol/L and 233.35 pmol/L, respectively, and level of folic acid was higher in rural than that in urban women, but no significant difference in deficiency of folic acid between rural and urban was found. The average ratio of folic acid to homocysteine and that of vitamin B12 to homocysteine were higher in rural than those in urban women. It suggests that abnormal metabolism of homocysteine usually correlates with high incidence of neural tube defects in rural area. PMID:9812582

  11. IMPAIRED HOMOCYSTEINE TRANSSULFURATION IS AN INDICATOR OF ALCOHOLIC LIVER DISEASE

    PubMed Central

    Medici, Valentina; M.Peerson, Janet; Stabler, Sally P.; French, Samuel W.; Gregory, Jesse F.; Virata, Maria Catrina; Albanese, Antony; Bowlus, Christopher L.; Devaraj, Sridevi; Panacek, Edward A.; Rahim, Nazir; Richards, John R.; Rossaro, Lorenzo; Halsted, Charles H.

    2010-01-01

    Background & Aims Although abnormal hepatic methionine metabolism plays a central role in the pathogenesis of experimental alcoholic liver disease (ALD), its relationship to the risk and severity of clinical ALD is not known. The aim of this clinical study was to determine the relationship between serum levels of methionine metabolites in chronic alcoholics and the risk and pathological severity of ALD. Methods Serum levels of liver function biochemical markers, vitamin B6, vitamin B12, folate, homocysteine, methionine, S-adenosylmethionine, S-adenosylhomocysteine, cystathionine, cysteine, α-aminobutyrate, glycine, serine, and dimethylglycine were measured in 40 ALD patients, of whom 24 had liver biopsies, 26 were active drinkers without liver disease, and 28 were healthy subjects. Results Serum homocysteine was elevated in all alcoholics, whereas ALD patients had low vitamin B6 with elevated cystathionine and decreased α-aminobutyrate/cystathionine ratios, consistent with decreased activity of vitamin B6 dependent cystathionase. The α-aminobutyrate/cystathionine ratio predicted the presence of ALD, while cystathionine correlated with the stage of fibrosis in all ALD patients. Conclusions The predictive role of the α- aminobutyrate/cystathionine ratio for the presence of ALD and the correlation between cystathionine serum levels with the severity of fibrosis point to the importance of the homocysteine transsulfuration pathway in ALD and may have important diagnostic and therapeutic implications. PMID:20561703

  12. Neprilysin Inhibits Coagulation through Proteolytic Inactivation of Fibrinogen

    PubMed Central

    Burrell, Matthew; Henderson, Simon J.; Ravnefjord, Anna; Schweikart, Fritz; Fowler, Susan B.; Witt, Susanne; Hansson, Kenny M.; Webster, Carl I.

    2016-01-01

    Neprilysin (NEP) is an endogenous protease that degrades a wide range of peptides including amyloid beta (Aβ), the main pathological component of Alzheimer’s disease (AD). We have engineered NEP as a potential therapeutic for AD but found in pre-clinical safety testing that this variant increased prothrombin time (PT) and activated partial thromboplastin time (APTT). The objective of the current study was to investigate the effect of wild type NEP and the engineered variant on coagulation and define the mechanism by which this effect is mediated. PT and APTT were measured in cynomolgus monkeys and rats dosed with a human serum albumin fusion with an engineered variant of NEP (HSA-NEPv) as well as in control plasma spiked with wild type or variant enzyme. The coagulation factor targeted by NEP was determined using in vitro prothrombinase, calibrated automated thrombogram (CAT) and fibrin formation assays as well as N-terminal sequencing of fibrinogen treated with the enzyme. We demonstrate that HSA-NEP wild type and HSA-NEPv unexpectedly impaired coagulation, increasing PT and APTT in plasma samples and abolishing fibrin formation from fibrinogen. This effect was mediated through cleavage of the N-termini of the Aα- and Bβ-chains of fibrinogen thereby significantly impairing initiation of fibrin formation by thrombin. Fibrinogen has therefore been identified for the first time as a substrate for NEP wild type suggesting that the enzyme may have a role in regulating fibrin formation. Reductions in NEP levels observed in AD and cerebral amyloid angiopathy may contribute to neurovascular degeneration observed in these conditions. PMID:27437944

  13. Recovery of fibrinogen concentrate after intraosseous application is equivalent to the intravenous route in a porcine model of hemodilution

    PubMed Central

    Schlimp, Christoph J.; Solomon, Cristina; Keibl, Claudia; Zipperle, Johannes; Nürnberger, Sylvia; Öhlinger, Wolfgang; Redl, Heinz; Schöchl, Herbert

    2014-01-01

    BACKGROUND Fibrinogen concentrate is increasingly considered as a hemostatic agent for trauma patients experiencing bleeding. Placing a venous access is sometimes challenging during severe hemorrhage. Intraosseous access may be considered instead. Studies of intraosseous infusion of coagulation factor concentrates are limited. We investigated in vivo recovery following intraosseous administration of fibrinogen concentrate and compared the results with intravenous administration. METHODS This study was performed on 12 pigs (mean [SD] body weight, 34.1 [2.8] kg). Following controlled blood loss (35 mL/kg) and fluid replacement with balanced crystalloid solution, intraosseous (n = 6) administration of fibrinogen concentrate (80 mg per kilogram of bodyweight) in the proximal tibia was compared with intravenous (n = 6) administration of the same dose (fibrinogen infusion time approximately 5 minutes in both groups). The following laboratory parameters were assessed: blood cell count, prothrombin time index, activated partial thromboplastin time, and plasma fibrinogen concentration (Clauss assay). Coagulation status was also assessed by thromboelastometry. RESULTS All tested laboratory parameters were comparable between the intraosseous and intravenous groups at baseline, hemodilution, and 30 minutes after fibrinogen concentrate administration. In vivo recovery of fibrinogen was also similar in the two groups (89% [23%] and 91% [22%], respectively). There were no significant between-group differences in any of the thromboelastometric parameters. Histologic examination indicated no adverse effects on the tissue surrounding the intraosseous administration site. CONCLUSION This study suggests that intraosseous administration of fibrinogen concentrate results in a recovery of fibrinogen similar to that of intravenous administration. The intraosseous route of fibrinogen concentrate could be a valuable alternative in situations where intravenous access is not feasible or would

  14. Platelet Glycoproteins and Fibrinogen in Recovery from Idiopathic Sudden Hearing Loss

    PubMed Central

    Gorzelniak, Kerstin; Bremer, Alexis; Rudack, Claudia; Walter, Michael

    2014-01-01

    Background The pathomechanism and location of idiopathic sudden sensorineural hearing loss (ISSHL) is unclear. In a previous case-control study, we found elevated fibrinogen concentrations and a higher prevalence of T allele carriers of the glycoprotein (Gp) Ia C807T polymorphism in ISSHL patients. Methodology 127 patients with ISSHL (mean age 53.3 years, 48.8% females), who underwent a standard therapy with high dose steroids, pentoxifyllin and sterofundine over 8 days were included. We examined the influence of GpIa genotype and fibrinogen (BclI-, A312-, HaeIII-) genotype and fibrinogen plasma levels on hearing recovery after 8 weeks (change from baseline: 0 dB  =  no recovery, >0 to 10 dB = moderate recovery, >10 dB = good recovery). In a subsample of 59 patients with ISSHL, we further studied the association of platelet glycoprotein GpIa, Ib and IIIa densities on hearing recovery as well as the possible effect-modification of platelet glycoproteins on hearing recovery by plasma fibrinogen. Results In univariate analysis, neither the GpIa genotype nor fibrinogen genotype (all p>0.1) but lower fibrinogen levels (p = 0.029), less vertigo (p = 0.002) and lower GpIIIa receptor density (p = 0.037, n = 59) were associated with hearing recovery. In multivariate analysis, fibrinogen significantly modified the effect of GPIa receptor density on good hearing recovery (effect-modification on multiplicative scale OR = 0.45 (95% confidence interval (0.21–0.94)), p = 0.03). GPIb receptor density below the mean was associated with a 2-fold increase in good hearing recovery both in patients with fibrinogen levels above (p = 0.04) as well as in patients with fibrinogen levels below the mean (p = 0.06). There was no indication for an effect-modification (p = 0.97). Conclusions The findings suggest a vascular/rheological origin of ISSHL with unique features of thrombosis in the inner ear artery that may include complex

  15. Homocysteine: cardiovascular risk factor in children and adolescents?

    PubMed

    Leal, Adriana Amorim De Farias; Palmeira, Astrid Camêlo; Castro, Gabriella Menezes Almeida De; Simões, Mônica Oliveira Da Silva; Ramos, Alessandra Teixeira; Medeiros, Carla Campos Muniz

    2013-01-01

    The aim of this study was to identify publications in literature that investigated Homocysteine (He) as a risk factor for CVD among children and adolescents. An active search for information in LILACS, IBECS, Science Direct, Medline and Cochrane Library databases was conducted using the following combination of keywords "homocysteine", "cardiovascular diseases", "child" and "adolescent". Fifteen articles were analyzed showing direct relationship with increasing age (8 studies) and male gender (10 studies), and an inverse relationship with serum vitamins B6, B12 and folate levels. Thus, the results suggest that more research must be carried through in order to determine in a more coherent way the causes of the hiperhomocisteinemia in the pediatric population, guiding for an adequate diet, rich in nutrients necessary to favor the metabolism of the He. PMID:24182942

  16. Nitric oxide releasing material adsorbs more fibrinogen.

    PubMed

    Lantvit, Sarah M; Barrett, Brittany J; Reynolds, Melissa M

    2013-11-01

    One mechanism of the failure of blood-contacting devices is clotting. Nitric oxide (NO) releasing materials are seen as a viable solution to the mediation of surface clotting by preventing platelet activation; however, NO's involvement in preventing clot formation extends beyond controlling platelet function. In this study, we evaluate NO's effect on factor XII (fibrinogen) adsorption and activation, which causes the initiation of the intrinsic arm of the coagulation cascade. This is done by utilizing a model plasticized poly(vinyl) chloride (PVC), N-diazeniumdiolate system and looking at the adsorption of fibrinogen, an important clotting protein, to these surfaces. The materials have been prepared in such a way to eliminate changes in surface properties between the control (plasticized PVC) and composite (NO-releasing) materials. This allows us to isolate NO release and determine the effect on the adsorption of fibrinogen, to the material surface. Surprisingly, it was found that an NO releasing material with a surface flux of 17.4 ± 0.5 × 10(-10) mol NO cm(-2) min(-1) showed a significant increase in the amount of fibrinogen adsorbed to the material surface compared to one with a flux of 13.0 ± 1.6 × 10(-10) mol NO cm(-2) min(-1) and the control (2334 ± 496, 226 ± 99, and 103 ±31% fibrinogen adsorbed of control, respectively). This study suggests that NO's role in controlling clotting is extended beyond platelet activation. PMID:23554300

  17. Plasma fibrinogen in women: relationships with oral contraception, the menopause and hormone replacement therapy.

    PubMed

    Lee, A J; Lowe, G D; Smith, W C; Tunstall-Pedoe, H

    1993-04-01

    Plasma fibrinogen was measured in 4837 women aged 25-64 years as part of the Scottish Heart Health Study and Scottish MONICA population surveys. The relationships of oral contraceptive use, the menopause and hormone replacement therapy were examined. Univariate analyses found that women with a history of oral contraceptive use, premenopausal women and those on hormone replacement therapy all had significantly lower fibrinogen levels than women who had never used oral contraceptives, postmenopausal women and non-hormone replacement users respectively. These differences persisted after age standardization. On multivariate analysis, menopausal status and hormone replacement therapy had independent effects on fibrinogen levels. Together with the common risk factors, 9.9% of the total variation in plasma fibrinogen levels was explained. However, less than 1% of this was from the combined menopausal and hormonal factors. These results confirm a postmenopausal rise in fibrinogen level which may be relevant to an increased risk of coronary heart disease. In addition, a protective effect with hormone replacement therapy is noted, although this was probably due to selection bias.

  18. Higher homocysteine associated with thinner cortical gray matter in 803 ADNI subjects

    PubMed Central

    Madsen, Sarah K.; Rajagopalan, Priya; Joshi, Shantanu H.; Toga, Arthur W.; Thompson, Paul M.

    2014-01-01

    A significant portion of our risk for dementia in old age is associated with lifestyle factors (diet, exercise, and cardiovascular health) that are modifiable, at least in principle. One such risk factor – high homocysteine levels in the blood – is known to increase risk for Alzheimer’s disease and vascular disorders. Here we set out to understand how homocysteine levels relate to 3D surface-based maps of cortical gray matter distribution (thickness, volume, surface area) computed from brain MRI in 803 elderly subjects from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) dataset. Individuals with higher plasma levels of homocysteine had lower gray matter thickness in bilateral frontal, parietal, occipital and right temporal regions; and lower gray matter volumes in left frontal, parietal, temporal, and occipital regions, after controlling for diagnosis, age, and sex, and after correcting for multiple comparisons. No significant within-group associations were found in cognitively healthy people, mild cognitive impairment, or Alzheimer’s disease. These regional differences in gray matter structure may be useful biomarkers to assess the effectiveness of interventions, such as vitamin B supplements, that aim to prevent homocysteine-related brain atrophy by normalizing homocysteine levels. PMID:25444607

  19. Homocysteine excess: delineating the possible mechanism of neurotoxicity and depression.

    PubMed

    Bhatia, Pankaj; Singh, Nirmal

    2015-12-01

    Homocysteine (Hcy) is a nonproteogenic sulfur containing amino acid derived from dietary methionine through demethylation. Homocysteine can be re-methylated to methionine [precursor of S-adenosylmethionine (SAM)] via the re-methylation or 5-methyltetrahydrofolate pathway or undergoes transsulfuration to form cysteine by the action of metabolic enzymes and cofactors. Impaired metabolism due to genetic alteration in metabolic enzymes (methionine synthase, methyltetrahydrofolate reductase (MTHFR), cystathionine β-synthase (CβS), and cystathionine-γ-lyase (CγL) or deficiency in cofactors (vitamin B6 , B12 , folate) may lead to acquired metabolic anomaly known as hyperhomocysteinemia. Hcy excess decreases the S-adenosylmethionine (SAM)-dependent synthesis of catecholamines, viz. dopamine, norepinephrine, epinephrine, and noncatecholamine, viz. serotonin (5-HT), due to genetic alteration in key enzyme MTHFR in the homocysteine metabolism pathway that leads to depression. Thus, hyperhomocysteinemia (HHcy)-induced SAM level is influenced by the single nucleotide polymorphism (SNP) MTHFR C677T. Furthermore, HHcy leads to production of precarious neurotoxic product homocysteic acid (HCA) and cysteine sulfinic acid (CSA) which acts as an N-methyl-D-aspartate (NMDA) receptor agonist and has neurotoxic effects on dopaminergic neurons. In the current review, an attempt has been made to discuss the neurotoxic effects of HHcy in the pathogenesis of depression. PMID:26376956

  20. Importance of fibrinogen in dilutional coagulopathy after neurosurgical procedures: A descriptive study

    PubMed Central

    Nair, Shalini; Nair, Bijesh Ravindran; Vidyasagar, Ajay; Joseph, Mathew

    2016-01-01

    Background and Aims: The routine management of coagulopathy during surgery involves assessing haemoglobin, prothrombin time (PT), activated partial thromboplastin time (aPTT) and platelets. Correction of these parameters involves administration of blood, fresh frozen plasma and platelet concentrates. The study was aimed at identifying the most common coagulation abnormality during neurosurgical procedures and the treatment of dilutional coagulopathy with blood components. Methods: During 2 years period, all adult patients undergoing neurosurgical procedures who were transfused two or more units of red cells were prospectively evaluated for the presence of a coagulopathy. PT, aPTT, platelet count and fibrinogen levels were estimated before starting a component therapy. Results: After assessing PT, aPTT, platelet count and fibrinogen levels following two or more blood transfusions, thirty patients were found to have at least one abnormal parameter that required administration of a blood product. The most common abnormality was a low fibrinogen level, seen in 26 patients; this was the only abnormality in three patients. No patient was found to have an abnormal PT or aPTT without either the fibrinogen concentration or platelet count or both being low. Conclusion: Low fibrinogen concentration was the most common coagulation abnormality found after blood transfusions for neurosurgical procedures. PMID:27601735

  1. Methyl Vitamin B12 but not methylfolate rescues a motor neuron-like cell line from homocysteine-mediated cell death

    SciTech Connect

    Hemendinger, Richelle A. Armstrong, Edward J.; Brooks, Benjamin Rix

    2011-03-15

    Homocysteine is an excitatory amino acid implicated in multiple diseases including amyotrophic lateral sclerosis (ALS). Information on the toxicity of homocysteine in motor neurons is limited and few studies have examined how this toxicity can be modulated. In NSC-34D cells (a hybrid cell line derived from motor neuron-neuroblastoma), homocysteine induces apoptotic cell death in the millimolar range with a TC{sub 50} (toxic concentration at which 50% of maximal cell death is achieved) of 2.2 mM, confirmed by activation of caspase 3/7. Induction of apoptosis was independent of short-term reactive oxygen species (ROS) generation. Methyl Vitamin B12 (MeCbl) and methyl tetrahydrofolate (MTHF), used clinically to treat elevated homocysteine levels, were tested for their ability to reverse homocysteine-mediated motor neuron cell death. MeCbl in the micromolar range was able to provide neuroprotection (2 h pretreatment prior to homocysteine) and neurorescue (simultaneous exposure with homocysteine) against millimolar homocysteine with an IC{sub 50} (concentration at which 50% of maximal cell death is inhibited) of 0.6 {mu}M and 0.4 {mu}M, respectively. In contrast, MTHF (up to 10 {mu}M) had no effect on homocysteine-mediated cell death. MeCbl inhibited caspase 3/7 activation by homocysteine in a time- and dose-dependent manner, whereas MTHF had no effect. We conclude that MeCbl is effective against homocysteine-induced cell death in motor neurons in a ROS-independent manner, via a reduction in caspase activation and apoptosis. MeCbl decreases Hcy induced motor neuron death in vitro in a hybrid cell line derived from motor neuron-neuroblastoma and may play a role in the treatment of late stage ALS where HCy levels are increased in animal models of ALS.

  2. Homocysteine lowering interventions for preventing cardiovascular events

    PubMed Central

    Martí-Carvajal, Arturo J; Solà, Ivan; Lathyris, Dimitrios; Salanti, Georgia

    2014-01-01

    Background Cardiovascular disease such as coronary artery disease, stroke and congestive heart failure, is a leading cause of death worldwide. A postulated risk factor is elevated circulating total homocysteine (tHcy) levels which is influenced mainly by blood levels of cyanocobalamin (vitamin B12), folic acid (vitamin B9) and pyridoxine (vitamin B6). There is uncertainty regarding the strength of association between tHcy and the risk of cardiovascular disease. Objectives To assess the clinical effectiveness of homocysteine-lowering interventions (HLI) in people with or without pre-existing cardiovascular disease. Search methods We searched The Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (issue 3 2008), MEDLINE (1950 to August 2008), EMBASE (1988 to August 2008), and LILACS (1982 to September 2, 2008). We also searched in Allied and Complementary Medicine (AMED; 1985 to August 2008), ISI Web of Science (1993 to August 2008), and the Cochrane Stroke Group Specialised Register (April 2007). We hand searched pertinent journals and the reference lists of included papers. We also contacted researchers in the field. There was no language restriction in the search. Selection criteria We included randomised clinical trials (RCTs) assessing the effects of HLI for preventing cardiovascular events with a follow-up period of 1 year or longer. We considered myocardial infarction and stroke as the primary outcomes. We excluded studies in patients with end-stage renal disease. Data collection and analysis We independently performed study selection, risk of bias assessment and data extraction. We estimated relative risks (RR) for dichotomous outcomes. We measured statistical heterogeneity using I2. We used a random-effects model to synthesise the findings. Main results We included eight RCTs involving 24,210 participants with a low risk of bias in general terms. HLI did not reduce the risk of non-fatal or fatal myocardial infarction, stroke, or

  3. Homocysteine Induces Heme Oxygenase-1 Expression via Transcription Factor Nrf2 Activation in HepG2 Cells

    PubMed Central

    Mani, Monireh; Golmohammadi, Taghi; Khaghani, Shahnaz; Zamani, Zahra; Azadmanesh, Kayhan; Meshkani, Reza; Pasalar, Parvin

    2013-01-01

    Background: Elevated level of plasma homocysteine has been related to various diseases. Patients with hyperhomocysteinemia can develop hepatic steatosis and fibrosis. We hypothesized that oxidative stress induced by homocysteine might play an important role in pathogenesis of liver injury. Also, the cellular response designed to combat oxidative stress is primarily controlled by the transcription factor Nrf2, a principal inducer of anti-oxidant and phase II-related genes. Methods: HepG2 cells were treated with homocysteine in different time periods. Glutathione content was measured by flowcytometry. Using electrophoretic mobility shift assay (EMSA) and Western-blotting, anti-oxidant response element (ARE)-binding activity of Nrf2 for heme ocygenase-1 (HO-1) was demonstrated. Real time RT-PCR and Western-blotting were performed to evaluate whether homocysteine was able to induce mRNA and protein expression of HO-1. Results: The role of Nrf2 in cellular response to homocysteine is substantiated by the following observations in HepG2 cells exposed to homocysteine (i) Western-blotting revealed that Nrf2 is strongly stabilized and became detectable in nuclear extracts. (ii) EMSA demonstrated increased binding of Nrf2 to oligomers containing HO-1 promoter-specific ARE-binding site. (iii) Real time RT-PCR and Western-blotting revealed increased mRNA and protein expression of inducible gene HO-1 after treatment with homocysteine. Conclusion: Data presented in the current study provide direct evidence that the immediate cellular response to oxidative stress provoked by homocysteine is orchestrated mainly by the Nrf2-ARE pathway. Therefore, induction of Nrf2-ARE-dependent expression of HO-1 could be a therapeutic option for hepatic cells damage induced by homocysteine. PMID:23567851

  4. Regenerative Surface Plasmon Resonance (SPR) biosensor: real-time measurement of fibrinogen in undiluted human serum using the competitive adsorption of proteins.

    PubMed

    Wang, Ran; Lajevardi-Khosh, Arad; Choi, Seokheun; Chae, Junseok

    2011-10-15

    Epidemiological studies suggest that elevated plasma fibrinogen levels are associated with an increased risk of cardiovascular disorders. Normal fibrinogen level is in the range of 1.5-4.5mg/mL, depending upon both genetic (intrinsic) and environmental (extrinsic) factors. An increase of 0.25mg/mL from the normal level can often be correlated with a high risk of cardiovascular disease. Thus, it is useful to monitor fibrinogen level in serum of a patient for clinical diagnosis. We report a regenerative biosensor that measures real-time fibrinogen levels in undiluted serum. The biosensor uses Surface Plasmon Resonance (SPR), highly sensitive optical technique. The biosensor does not use bio-receptors (i.e., antibodies, enzymes, DNA, etc.) unlike conventional biosensors, and deploys the nature of competitive adsorption of proteins to achieve selective detection of fibrinogen. We measured fibrinogen-spiked serum samples with a concentration of 1.5-4.5 mg/mL, and repeated six measurement trials to obtain statistical distribution of the measurements using the regeneration method of the sensing surface. The SPR biosensor has a sensitivity of 42 mDeg/(mg/mL) for a fibrinogen concentration in the range of 0.5-2.5 mg/mL, whereas it was hard to correlate the measurements to the spiked-fibrinogen samples of above 2.5 mg/mL.

  5. Plasma homocysteine concentration in children with chronic renal failure.

    PubMed

    Merouani, A; Lambert, M; Delvin, E E; Genest, J; Robitaille, P; Rozen, R

    2001-10-01

    Hyperhomocysteinemia, a risk factor for vascular disease, is commonly found in adult patients with end-stage renal disease. Major determinants of elevated plasma homocysteine levels in these patients include deficiencies in folate and vitamin B12, methylenetetrahydrofolate reductase (MTHFR) genotype and renal function. Little information is available for children with chronic renal failure (CRF). The prevalence and the factors that affect plasma homocysteine concentration were determined in children. Twenty-nine children with various degrees of CRF (15 were dialyzed, 14 were not dialyzed) were compared with 57 age- and sex-matched healthy children. Homocysteine concentrations were higher in patients than controls (17.3 micromol/l vs 6.8 micromol/l, P<0.0001) and hyperhomocysteinemia (>95th percentile for controls: 14.0 micromol/l) was seen in 62.0% of patients and 5.2% of controls. Folate concentrations were lower in patients (9.9 nmol/l) than controls (13.5 nmol/l), P<0.01. Vitamin B12 was similar in patients (322 pmol/l) and controls (284 pmol/l). Dialyzed patients have a higher prevalence of hyperhomocysteinemia than nondialyzed patients (87% vs 35%). Dialyzed patients with MTHFR mutation have higher plasma homocysteine (28.5 micromol/l) than nondialyzed patients with the mutation (10.7 micromol/l), P<0.002. In our study, differences between controls and patients in plasma homocysteine concentrations are observed when age is greater then 92 months, folate less than 21.6 nmol/l and vitamin B12 less than 522 pmol/l. Our study shows that hyperhomocysteinemia is common in children with CRF and is associated with low folate and normal vitamin B12 status, compared to normal children. Among the patients, the dialyzed patients with the MTHFR mutation are particularly at risk for hyperhomocysteinemia. Further studies are needed to investigate therapeutic interventions and the potential link with vascular complications in these patients. PMID:11605787

  6. Effects of folic acid supplementation on serum folate and plasma homocysteine concentrations in older adults: a dose-response trial.

    PubMed

    Anderson, Cheryl A M; Jee, Sun Ha; Charleston, Jeanne; Narrett, Matthew; Appel, Lawrence J

    2010-10-15

    The authors' objective in this study was to estimate the changes in serum folate and homocysteine concentration that resulted from 6 weeks of supplementation with folic acid. A randomized, double-blind, placebo-controlled, dose-response trial with a parallel-group design was conducted. A total of 133 participants aged 60-90 years (70% female, 19% nonwhite) were assigned to receive 0, 100, 400, 1,000, or 2,000 μg/day of folic acid for 6 weeks. Data were collected in the United States between June and September 1996. At baseline, median serum folate and plasma homocysteine concentrations were 5.7 ng/mL (interquartile range (25th-75th percentiles), 4.1-7.8) and 8.3 μmol/L (interquartile range, 7.1-10.0), respectively. As the folic acid dose increased, serum folate levels increased (P-trend < 0.001). There was no dose-response relation with homocysteine level among all participants. In analyses restricted to persons with the lowest serum folate concentration (<4.5 ng/mL) at baseline, there was a trend (P = 0.06) toward decreased homocysteine levels with increasing folic acid dose. In healthy, older adults with adequate folate status, folic acid supplementation is not beneficial for homocysteine reduction. However, for older adults with low serum folate levels, supplementation will improve folate status and may be beneficial for lowering homocysteine concentrations.

  7. Association between Homocysteine and Bone Mineral Density according to Age and Sex in Healthy Adults

    PubMed Central

    Kim, Joo Il; Moon, Ji Hyun; Chung, Hye Won; Kong, Mi Hee

    2016-01-01

    Background There are several studies about the relationship between serum homocysteine levels and bone mineral density (BMD), but the results are varied, and the studies are limited in Korea. In our study, the relationship between serum homocysteine levels and BMD by part according to age and sex is investigated. Methods From March 2012 to July 2015, the 3,337 healthy adults who took a medical examination were recruited. Subjects filled in the self-recording type questionnaire and physical examination, blood test, BMD of lumbar spine and femur were measured. After sorting by aging (≤49 year old, 50-59 year old, ≥60 year old) and sex, the results were adjusted with age and body mass index (BMI) and the relationship between serum homocysteine levels and BMD by lumbar spine and femur was analyzed by multiple regression analysis. Results As results of analysis, with the adjustment with age and BMI, all age groups of men had no significant relationship between log-converted serum homocysteine levels and BMD. In women aged under 50, there were significantly negative relationships at lumbar spine (β=-0.028, P=0.038), femur neck (β=-0.062, P=0.001), and total hip (β=-0.076, P<0.001), but there was no significant relationship in other age groups (50-59 year old and ≥60 year old). Conclusions As the serum homocysteine levels increased in women aged under 50, BMD of the lumbar spine and femur decreased, and correlations between homocysteine and BMD were different by sex and age. PMID:27622176

  8. Association between Homocysteine and Bone Mineral Density according to Age and Sex in Healthy Adults

    PubMed Central

    Kim, Joo Il; Moon, Ji Hyun; Chung, Hye Won; Kong, Mi Hee

    2016-01-01

    Background There are several studies about the relationship between serum homocysteine levels and bone mineral density (BMD), but the results are varied, and the studies are limited in Korea. In our study, the relationship between serum homocysteine levels and BMD by part according to age and sex is investigated. Methods From March 2012 to July 2015, the 3,337 healthy adults who took a medical examination were recruited. Subjects filled in the self-recording type questionnaire and physical examination, blood test, BMD of lumbar spine and femur were measured. After sorting by aging (≤49 year old, 50-59 year old, ≥60 year old) and sex, the results were adjusted with age and body mass index (BMI) and the relationship between serum homocysteine levels and BMD by lumbar spine and femur was analyzed by multiple regression analysis. Results As results of analysis, with the adjustment with age and BMI, all age groups of men had no significant relationship between log-converted serum homocysteine levels and BMD. In women aged under 50, there were significantly negative relationships at lumbar spine (β=-0.028, P=0.038), femur neck (β=-0.062, P=0.001), and total hip (β=-0.076, P<0.001), but there was no significant relationship in other age groups (50-59 year old and ≥60 year old). Conclusions As the serum homocysteine levels increased in women aged under 50, BMD of the lumbar spine and femur decreased, and correlations between homocysteine and BMD were different by sex and age.

  9. Molecular characterization of betaine-homocysteine methyltransferase 1 from the liver, and effects of aestivation on its expressions and homocysteine concentrations in the liver, kidney and muscle, of the African lungfish, Protopterus annectens.

    PubMed

    Ong, Jasmine L Y; Woo, Jia M; Hiong, Kum C; Ching, Biyun; Wong, Wai P; Chew, Shit F; Ip, Yuen K

    2015-05-01

    Homocysteine accumulation has numerous deleterious effects, and betaine-homocysteine S-methyltransferase (BHMT) catalyses the synthesis of methionine from homocysteine and betaine. This study aimed to determine homocysteine concentrations, and mRNA expression levels and protein abundances of bhmt1/Bhmt1 in the liver, kidney and muscle of the African lungfish, Protopterus annectens, during the induction (6 days), maintenance (6 months) or arousal (3 days after arousal) phase of aestivation. The homocysteine concentration decreased significantly in the liver of P. annectens after 6 days or 6 months of aestivation, but it returned to the control level upon arousal. By contrast, homocysteine concentrations in the kidney and muscle remained unchanged during the three phases of aestivation. The complete coding cDNA sequence of bhmt1 from P. annectens consisted of 1236 bp, coding for 412 amino acids. The Bhmt1 from P. annectens had a close phylogenetic relationship with those from tetrapods and Callorhinchus milii. The expression of bhmt1 was detected in multiple organs/tissues of P. annectens, and this is the first report on the expression of bhmt1/Bhmt1 in animal skeletal muscle. The mRNA and protein expression levels of bhmt1/Bhmt1 were up-regulated in the liver of P. annectens during the induction and maintenance phases of aestivation, possibly to regulate the hepatic homocysteine concentration. The significant increase in hepatic Bhmt1 protein abundance during the arousal phase could be a response to increased cellular methylation for the purpose of tissue reconstruction. Unlike the liver, Bhmt1 expression in the kidney and muscle of P. annectens was regulated translationally, and its up-regulation could be crucial to prevent homocysteine accumulation.

  10. Fibrinogen Seoul (FGG Ala341Asp): a novel mutation associated with hypodysfibrinogenemia.

    PubMed

    Song, Kyung Soon; Park, Noh Jin; Choi, Jong Rak; Doh, Hyun Joo; Chung, Kwang Hoe

    2006-07-01

    Dysfibrinogenemia is a coagulation disorder caused by a variety of structural abnormalities in the fibrinogen molecule that result in fibrinogen function. The molecular basis of hypodysfibrinogenemia was investigated in a 66-year-old woman with peripheral artery obstructive disease and in her family members. Plasma level of functional fibrinogen determined using the Clauss method was lower (75 mg/dL; normal, 140-460 mg/dL) than that measured with immunologic nephelometric assay (137 mg/dL; normal, 180-400 mg/dL). Similar results were also observed in two family members through two generations. DNA was extracted from whole blood, and the coding regions and intron/exon boundaries of gamma chain gene (FGG) were amplified. A novel (Fibrinogen Seoul) heterozygous FGG mutation (GCT->GAT, Ala341Asp) was identified in all three affected family members. Thrombin-catalyzed polymerization was found to be defective on the analysis of purified fibinogen from the propositus. Molecular modeling also showed a conformational change of fibrinogen structure.

  11. Salidroside Improves Homocysteine-Induced Endothelial Dysfunction by Reducing Oxidative Stress

    PubMed Central

    Leung, Sin Bond; Zhang, Huina; Lau, Chi Wai; Huang, Yu; Lin, Zhixiu

    2013-01-01

    Hyperhomocysteinemia is associated with an increased risk for cardiovascular diseases through increased oxidative stress. Salidroside is an active ingredient of the root of Rhodiola rosea with documented antioxidative, antihypoxia and neuroprotective properties. However, the vascular benefits of salidroside against endothelial dysfunction have yet to be explored. The present study, therefore, aimed to investigate the protective effect of salidroside on homocysteine-induced endothelial dysfunction. Functional studies on the rat aortas were performed to delineate the vascular effect of salidroside. DHE imaging was used to evaluate the reactive oxygen species (ROS) level in aortic wall and endothelial cells. Western blotting was performed to assess the protein expression associated with oxidative stress and nitric oxide (NO) bioavailability. Exposure to homocysteine attenuated endothelium-dependent relaxations in rat aortas while salidroside pretreatment rescued it. Salidroside inhibited homocystein-induced elevation in the NOX2 expression and ROS overproduction in both aortas and cultured endothelial cells and increased phosphorylation of eNOS which was diminished by homocysteine. The present study shows that salidroside is effective in preserving the NO bioavailability and thus protects against homocysteine-induced impairment of endothelium-dependent relaxations, largely through inhibiting the NOX2 expression and ROS production. Our results indicate a therapeutic potential of salidroside in the management of oxidative-stress-associated cardiovascular dysfunction. PMID:23589720

  12. Salidroside improves homocysteine-induced endothelial dysfunction by reducing oxidative stress.

    PubMed

    Leung, Sin Bond; Zhang, Huina; Lau, Chi Wai; Huang, Yu; Lin, Zhixiu

    2013-01-01

    Hyperhomocysteinemia is associated with an increased risk for cardiovascular diseases through increased oxidative stress. Salidroside is an active ingredient of the root of Rhodiola rosea with documented antioxidative, antihypoxia and neuroprotective properties. However, the vascular benefits of salidroside against endothelial dysfunction have yet to be explored. The present study, therefore, aimed to investigate the protective effect of salidroside on homocysteine-induced endothelial dysfunction. Functional studies on the rat aortas were performed to delineate the vascular effect of salidroside. DHE imaging was used to evaluate the reactive oxygen species (ROS) level in aortic wall and endothelial cells. Western blotting was performed to assess the protein expression associated with oxidative stress and nitric oxide (NO) bioavailability. Exposure to homocysteine attenuated endothelium-dependent relaxations in rat aortas while salidroside pretreatment rescued it. Salidroside inhibited homocystein-induced elevation in the NOX2 expression and ROS overproduction in both aortas and cultured endothelial cells and increased phosphorylation of eNOS which was diminished by homocysteine. The present study shows that salidroside is effective in preserving the NO bioavailability and thus protects against homocysteine-induced impairment of endothelium-dependent relaxations, largely through inhibiting the NOX2 expression and ROS production. Our results indicate a therapeutic potential of salidroside in the management of oxidative-stress-associated cardiovascular dysfunction. PMID:23589720

  13. A prospective study of maternal fatty acids, micronutrients and homocysteine and their association with birth outcome.

    PubMed

    Wadhwani, Nisha S; Pisal, Hemlata R; Mehendale, Savita S; Joshi, Sadhana R

    2015-10-01

    Our earlier studies both in animals and in humans have indicated that micronutrients (folic acid, vitamin B12) and long-chain polyunsaturated fatty acids, especially docosahexaenoic acid (DHA), are interlinked in the one-carbon cycle, which plays an important role in fetal 'programming' of adult diseases. The present study examines the levels of maternal and cord plasma fatty acids, maternal folate, vitamin B12 and homocysteine in healthy mothers at various time points during pregnancy and also examine an association between them. A longitudinal study of 106 normal pregnant women was carried out, and maternal blood was collected at three time points, viz., T1 = 16-20th week, T2 = 26-30th week and T3 = at delivery. Cord blood was collected at delivery. Fatty acids were estimated using a gas chromatograph. Levels of folate, vitamin B12 and homocysteine were estimated by the chemiluminescent microparticle immunoassay (CMIA) technology. Maternal plasma folate (P < 0.05), vitamin B12 (P < 0.01) and DHA (P < 0.05) levels were lowest, while maternal homocysteine levels were highest (P < 0.01) at T3. There was a negative association between maternal DHA and homocysteine at T2 (P < 0.05) and T3 (P < 0.01). There was a positive association between plasma DHA in maternal blood at T3 and cord blood. Furthermore, there was a positive association between maternal folate and vitamin B12 at T3 and baby weight, whereas maternal homocysteine at T1 were inversely associated with baby weight at delivery. Our study provides evidence for the associations of folic acid, vitamin B12, homocysteine with DHA and baby weight, suggesting that a balanced dietary supplementation of folate-vitamin B12-DHA during pregnancy may be beneficial.

  14. Dietary intake of S-(α-carboxybutyl)-DL-homocysteine induces hyperhomocysteinemia in rats

    PubMed Central

    Strakova, Jana; Williams, Kelly T.; Gupta, Sapna; Schalinske, Kevin L.; Kruger, Warren D.; Rozen, Rima; Jiracek, Jiri; Li, Lucas; Garrow, Timothy A.

    2010-01-01

    Betaine homocysteine S-methyltransferase (BHMT) catalyzes the transfer of a methyl group from betaine to homocysteine forming dimethylglycine and methionine. We previously showed that inhibiting BHMT in mice by intraperitoneal injection of S-(α-carboxybutyl)-DL-homocysteine (CBHcy) results in hyperhomocysteinemia. In the present study, CBHcy was fed to rats to determine whether it could be absorbed and cause hyperhomocysteinemia as observed for the intraperitoneal administration of the compound in mice. We hypothesized that dietary administered CBHcy will be absorbed and will result in the inhibition of BHMT and cause hyperhomocysteinemia. Rats were meal-fed every 8 hours an L-amino acid-defined diet either containing or devoid of CBHcy (5 mg/meal) for 3 days. The treatment decreased liver BHMT activity by 90% and had no effect on methionine synthase, methylenetetrahydrofolate reductase, phosphatidylethanolamine N-methyltransferase and CTP:phosphocholine cytidylyltransferase activities. In contrast, cystathionine β-synthase activity and immunodetectable protein decreased (56 and 26%, respectively) and glycine N-methyltransferase activity increased (52%) in CBHcy-treated rats. Liver S-adenosylmethionine levels decreased by 25% in CBHcy-treated rats and S-adenosylhomocysteine levels did not change. Further, plasma choline decreased (22%) and plasma betaine increased (15-fold) in CBHcy-treated rats. The treatment had no effect on global DNA and CpG island methylation, liver histology and plasma markers of liver damage. We conclude that CBHcy mediated BHMT inhibition causes an elevation in total plasma homocysteine that is not normalized by the folate-dependent conversion of homocysteine to methionine. Further, metabolic changes caused by BHMT inhibition affect cystathionine β-synthase and glycine N-methyltransferase activities, which further deteriorate plasma homocysteine levels. PMID:20797482

  15. [Mechanisms that protect against homocysteine toxicity].

    PubMed

    Zimny, Jarosław

    2008-01-01

    Elevated concentrations of homocysteine (Hcy) in human tissues have been correlated with some diseases, such as cardio-vascular, neurodegenerative, and kidney disorders. Hcy occurs in human blood in several forms. The most reactive is homocysteine thiolactone (HcyTl). It spontaneously homocysteinylates proteins impairing their functions. As has been evidenced recently, organisms developed protective mechanisms against the HcyTl toxicity. The first mechanism discovered was the calcium-dependent enzyme occurring in mammalian sera, known till then as paraoxonase, which hydrolyzes HcyTl to Hcy. Chronologically second mechanism discovered was urinary excretion of HcyTl. The third protective mechanism is the HcyTl hydrolysis catalyzed by intracellular enzyme known as bleomycin hydrolase. This review outlines current knowledge of the Hcy toxicity and of the three aforementioned protective mechanisms, emphasizing the role of bleomycin hydrolase/ homocysteine-thiolactonase. PMID:18610586

  16. Homocysteine thiolactone affects protein ubiquitination in yeast.

    PubMed

    Bretes, Ewa; Zimny, Jarosław

    2013-01-01

    The formation of homocysteine thiolactone (HcyTl) from homocysteine occurs in all examined so far organisms including bacteria, yeast, and humans. Protein N-homocysteinylation at the ε-amino group of lysine is an adverse result of HcyTl accumulation. Since tagging of proteins by ubiquitination before their proteasomal degradation takes place at the same residue, we wondered how N-homocysteinylation may affect the ubiquitination of proteins. We used different yeast strains carrying mutations in genes involved in the homocysteine metabolism. We found positive correlation between the concentration of endogenous HcyTl and the concentration of ubiquitinated proteins. This suggests that N-homocysteinylation of proteins apparently does not preclude but rather promotes their decomposition. PMID:24051443

  17. Inhibition of growth and p21ras methylation in vascular endothelial cells by homocysteine but not cysteine.

    PubMed

    Wang, H; Yoshizumi, M; Lai, K; Tsai, J C; Perrella, M A; Haber, E; Lee, M E

    1997-10-01

    Although hyperhomocysteinemia has been recognized recently as a prevalent risk factor for myocardial infarction and stroke, the mechanisms by which it accelerates arteriosclerosis have not been elucidated, mostly because the biological effects of homocysteine can only be demonstrated at very high concentrations and can be mimicked by cysteine, which indicates a lack of specificity. We found that 10-50 microM of homocysteine (a range that overlaps levels observed clinically) but not cysteine inhibited DNA synthesis in vascular endothelial cells (VEC) and arrested their growth at the G1 phase of the cell cycle. Homocysteine in this same range had no effect on the growth of vascular smooth muscle cells (VSMC) or fibroblasts. Homocysteine decreased carboxyl methylation of p21(ras) (a G1 regulator whose activity is regulated by prenylation and methylation in addition to GTP-GDP exchange) by 50% in VEC but not VSMC, a difference that may be explained by the ability of homocysteine to dramatically increase levels of S-adenosylhomocysteine, a potent inhibitor of methyltransferase, in VEC but not VSMC. Moreover, homocysteine-induced hypomethylation in VEC was associated with a 66% reduction in membrane-associated p21(ras) and a 67% reduction in extracellular signal-regulated kinase 1/2, which is a member of the mitogen-activated protein (MAP) kinase family. Because the MAP kinases have been implicated in cell growth, the p21(ras)-MAP kinase pathway may represent one of the mechanisms that mediates homocysteine's effect on VEC growth. VEC damage is a hallmark of arteriosclerosis. Homocysteine-induced inhibition of VEC growth may play an important role in this disease process.

  18. Sensitive Immunoassays of Nitrated Fibrinogen in Human Biofluids

    SciTech Connect

    Tang, Zhiwen; Wu, Hong; Du, Dan; Wang, Jun; Wang, Hua; Qian, Weijun; Bigelow, Diana J.; Pounds, Joel G.; Smith, Richard D.; Lin, Yuehe

    2010-05-05

    Three new sandwich immunoassays for detection of nitrated biomarker have been established with potential applications in biomedical studies and clinical practice. In this study, nitrated human fibrinogen, a potential oxidative stress biomarker for several pathologies, was chosen as the target. To improve the sensitivity and overcome the interference caused by the complexity of human biofluids, we developed three sandwich strategies using various combinations of primary antibody and secondary antibody. All three strategies demonstrated high sensitivity and selectivity towards nitrated forms of fibrinogen in buffer, but their performances were dramatically reduced when tested with human plasma and serum samples. Systematically optimizations were carried out to investigate the effects of numerous factors, including sampling, coating, blocking, and immunoreactions. Our final optimization results indicate that two of these strategies retain sufficient sensitivity and selectivity for use as assays in human physiological samples. Specifically, detection limits reached the pM level and the linear response ranges were up to nM level with a correlation coefficient > 0.99. To our best knowledge, this is the first example of using an electrochemical immunoassay for a nitrated biomarker in a physiological fluid. This novel approach provides a rapid, sensitive, selective, cost efficient and robust bioassay for detection of oxidative stress in pathology and for clinical applications. Moreover, the sandwich strategies developed in this paper can be readily used to establish effective methods targeting other nitration biomarkers.

  19. Plasma Fibrinogen as a Biomarker for Mortality and Hospitalized Exacerbations in People with COPD

    PubMed Central

    Mannino, David M; Tal-Singer, Ruth; Lomas, David A.; Vestbo, Jorgen; Graham Barr, R.; Tetzlaff, Kay; Lowings, Michael; Rennard, Stephen I.; Snyder, Jeffrey; Goldman, Mitchell; Martin, Ubaldo J.; Merrill, Deborah; Martin, Amber L.; Simeone, Jason C.; Fahrbach, Kyle; Murphy, Brian; Leidy, Nancy; Miller, Bruce

    2014-01-01

    Background In 2010 the COPD Foundation established the COPD Biomarkers Qualification Consortium (CBQC) as a partnership between the Foundation, the Food and Drug Administration (FDA), and the pharmaceutical industry to pool publicly-funded and industry data to develop innovative tools to facilitate the development and approval of new therapies for COPD. We present data from the initial project seeking regulatory qualification of fibrinogen as a biomarker for the stratification of COPD patients into clinical trials. Methods This analysis pooled data from 4 publicly-funded studies and 1 industry study into a common database resulting in 6376 individuals with spirometric evidence of COPD. We used a threshold of 350 mg/dL to determine high vs. low fibrinogen, and determined the subsequent risk of hospitalizations from exacerbations and death using Cox proportional hazards models. Results High fibrinogen levels at baseline were present in 2853 (44.7%) of individuals with COPD. High fibrinogen was associated with an increased risk of hospitalized COPD exacerbations within 12 months (hazard ratio [HR]: 1.64; 95% confidence interval [CI]: 1.39–1.93) among participants in the Atherosclerosis Risk in Communities Study (ARIC), the Cardiovascular Health Study (CHS), and the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) study. High fibrinogen was associated with an increased risk of death within 36 months (HR: 1.94; 95% CI: 1.62–2.31) among all participants. Conclusions Fibrinogen levels ≥ 350 mg/dL identify COPD individuals at an increased risk of exacerbations and death and could be a useful biomarker for enriching clinical trials in the COPD population. PMID:25685850

  20. A Multi-Ethnic Meta-Analysis of Genome-Wide Association Studies in Over 100,000 Subjects Identifies 23 Fibrinogen-Associated Loci but no Strong Evidence of a Causal Association between Circulating Fibrinogen and Cardiovascular Disease

    PubMed Central

    Sabater-Lleal, Maria; Huang, Jie; Chasman, Daniel; Naitza, Silvia; Dehghan, Abbas; Johnson, Andrew D; Teumer, Alexander; Reiner, Alex P; Folkersen, Lasse; Basu, Saonli; Rudnicka, Alicja R; Trompet, Stella; Mälarstig, Anders; Baumert, Jens; Bis, Joshua C.; Guo, Xiuqing; Hottenga, Jouke J; Shin, So-Youn; Lopez, Lorna M; Lahti, Jari; Tanaka, Toshiko; Yanek, Lisa R; Oudot-Mellakh, Tiphaine; Wilson, James F; Navarro, Pau; Huffman, Jennifer E; Zemunik, Tatijana; Redline, Susan; Mehra, Reena; Pulanic, Drazen; Rudan, Igor; Wright, Alan F; Kolcic, Ivana; Polasek, Ozren; Wild, Sarah H; Campbell, Harry; Curb, J David; Wallace, Robert; Liu, Simin; Eaton, Charles B.; Becker, Diane M.; Becker, Lewis C.; Bandinelli, Stefania; Räikkönen, Katri; Widen, Elisabeth; Palotie, Aarno; Fornage, Myriam; Green, David; Gross, Myron; Davies, Gail; Harris, Sarah E; Liewald, David C; Starr, John M; Williams, Frances M.K.; Grant, P.J.; Spector, Timothy D.; Strawbridge, Rona J; Silveira, Angela; Sennblad, Bengt; Rivadeneira, Fernando; Uitterlinden, Andre G; Franco, Oscar H; Hofman, Albert; van Dongen, Jenny; Willemsen, G; Boomsma, Dorret I; Yao, Jie; Jenny, Nancy Swords; Haritunians, Talin; McKnight, Barbara; Lumley, Thomas; Taylor, Kent D; Rotter, Jerome I; Psaty, Bruce M; Peters, Annette; Gieger, Christian; Illig, Thomas; Grotevendt, Anne; Homuth, Georg; Völzke, Henry; Kocher, Thomas; Goel, Anuj; Franzosi, Maria Grazia; Seedorf, Udo; Clarke, Robert; Steri, Maristella; Tarasov, Kirill V; Sanna, Serena; Schlessinger, David; Stott, David J; Sattar, Naveed; Buckley, Brendan M; Rumley, Ann; Lowe, Gordon D; McArdle, Wendy L; Chen, Ming-Huei; Tofler, Geoffrey H; Song, Jaejoon; Boerwinkle, Eric; Folsom, Aaron R.; Rose, Lynda M.; Franco-Cereceda, Anders; Teichert, Martina; Ikram, M Arfan; Mosley, Thomas H; Bevan, Steve; Dichgans, Martin; Rothwell, Peter M.; Sudlow, Cathie L M; Hopewell, Jemma C.; Chambers, John C.; Saleheen, Danish; Kooner, Jaspal S.; Danesh, John; Nelson, Christopher P; Erdmann, Jeanette; Reilly, Muredach P.; Kathiresan, Sekar; Schunkert, Heribert; Morange, Pierre-Emmanuel; Ferrucci, Luigi; Eriksson, Johan G; Jacobs, David; Deary, Ian J; Soranzo, Nicole; Witteman, Jacqueline CM; de Geus, Eco JC; Tracy, Russell P.; Hayward, Caroline; Koenig, Wolfgang; Cucca, Francesco; Jukema, J Wouter; Eriksson, Per; Seshadri, Sudha; Markus, Hugh S.; Watkins, Hugh; Samani, Nilesh J; Wallaschofski, Henri; Smith, Nicholas L.; Tregouet, David; Ridker, Paul M.; Tang, Weihong; Strachan, David P.; Hamsten, Anders; O’Donnell, Christopher J.

    2013-01-01

    Background Estimates of the heritability of plasma fibrinogen concentration, an established predictor of cardiovascular disease (CVD), range from 34 to 50%. Genetic variants so far identified by genome-wide association (GWA) studies only explain a small proportion (< 2%) of its variation. Methods and Results We conducted a meta-analysis of 28 GWA studies, including more than 90,000 subjects of European ancestry, the first GWA meta-analysis of fibrinogen levels in 7 African Americans studies totaling 8,289 samples, and a GWA study in Hispanic-Americans totaling 1,366 samples. Evaluation for association of SNPs with clinical outcomes included a total of 40,695 cases and 85,582 controls for coronary artery disease (CAD), 4,752 cases and 24,030 controls for stroke, and 3,208 cases and 46,167 controls for venous thromboembolism (VTE). Overall, we identified 24 genome-wide significant (P<5×10−8) independent signals in 23 loci, including 15 novel associations, together accounting for 3.7% of plasma fibrinogen variation. Gene-set enrichment analysis highlighted key roles in fibrinogen regulation for the three structural fibrinogen genes and pathways related to inflammation, adipocytokines and thyrotrophin-releasing hormone signaling. Whereas lead SNPs in a few loci were significantly associated with CAD, the combined effect of all 24 fibrinogen-associated lead SNPs was not significant for CAD, stroke or VTE. Conclusion We identify 23 robustly associated fibrinogen loci, 15 of which are new. Clinical outcome analysis of these loci does not support a causal relationship between circulating levels of fibrinogen and CAD, stroke or VTE. PMID:23969696

  1. Antiadhesive effect of fibrinogen: a safeguard for thrombus stability

    PubMed Central

    Lishko, Valeryi K.; Burke, Timothy; Ugarova, Tatiana

    2007-01-01

    The recruitment of phagocytic leukocytes to sites of vessel wall injury plays an important role in thrombus dissolution by proteases elaborated on their adhesion. However, leukocyte adhesion to the fibrin clot can be detrimental at the early stages of wound healing when hemostatic plug integrity is critical for preventing blood loss. Adhesion of circulating leukocytes to the insoluble fibrin(ogen) matrix is mediated by integrins and occurs in the presence of a high concentration of plasma fibrinogen. In this study, the possibility that soluble fibrinogen could protect fibrin from excessive adhesion of leukocytes was examined. Fibrinogen was a potent inhibitor of adhesion of U937 monocytoid cells and neutrophils to fibrin gel and immobilized fibrin(ogen). An investigation of the mechanism by which soluble fibrinogen exerts its influence on leukocyte adhesion indicated that it did not block integrins but rather associated with the fibrin(ogen) substrate. Consequently, leukocytes that engage fibrinogen molecules loosely bound to the surface of fibrin(ogen) matrix are not able to consolidate their grip on the substrate; subsequently, cells detach. This conclusion is based on the evidence obtained in adhesion studies using various cells and performed under static and flow conditions. These findings reveal a new role of fibrinogen in integrin-mediated leukocyte adhesion and suggest that this mechanism may protect the thrombus from premature dissolution. PMID:16849640

  2. Fibrinogen monolayer characterization by colloid deposition.

    PubMed

    Nattich-Rak, Małgorzata; Adamczyk, Zbigniew; Wasilewska, Monika; Sadowska, Marta

    2013-09-24

    Colloid particle deposition was applied to characterize bovine and human fibrinogen (Fb) monolayers on mica produced by controlled adsorption under diffusion transport at pH 3.5. The surface concentration of Fb was determined by AFM enumeration of single molecules adsorbed over the substrate surface. The electrokinetic properties of Fb monolayers for various ionic strength were studied using the in situ streaming potential measurements. It was shown that Fb adsorbs irreversibly on mica for a broad range of ionic strength of 4 × 10(-4) to 0.15 M, NaCl. The overcharging of initially negative mica surface occurred for fibrinogen surface concentrations higher than 1400 μm(-2). The orientation of fibrinogen molecules in the monolayers was evaluated by the colloid deposition method involving negatively charged polystyrene latex microspheres, 820 nm in diameter. An anomalous deposition of negative latex particles on substrates exhibiting a negative zeta potential was observed, which contradicts the mean-field DLVO predictions. Measurable deposition was observed even at low ionic strength where the minimum approach distance of latex particles to the interface exceeds 70 nm (for 6 × 10(-4) M NaCl). This confirms that, at this pH, fibrinogen molecules adsorb end-on on mica assuming extended conformations with the positive charge located mostly in the end part of the αA chains. This agrees with previous experimental and theoretical results discussed in the literature (Santore, M. M.; Wertz Ch. F. Protein spreading kinetics at liquid-solid interfaces via an adsorption probe method. Langmuir 2005, 21, 10172-10178 (experimental); Adamczyk, Z.; Barbasz, J.; Cieśla, M.; Mechanisms of fibrinogen adsorption at solid substrates. Langmuir, 2011, 25, 6868-6878 (theoretical)). This unusual latex deposition on Fb monolayers was quantitatively interpreted in terms of the model developed in ref 55 (Jin, X.; Wang, N. H. L.; Tarjus, G.; Talbot, J. Irreversible adsorption on nonuniform

  3. Fabrication of fibrinogen/P(LLA-CL) hybrid nanofibrous scaffold for potential soft tissue engineering applications.

    PubMed

    He, Chuanglong; Xu, Xiaohong; Zhang, Fan; Cao, Lijun; Feng, Wei; Wang, Hongsheng; Mo, Xiumei

    2011-06-01

    Coelectrospinning of native proteins and elastic synthetic polymers is an attractive technique to fabricate hybrid fibrous scaffolds that combine the bioactivity and mechanical features of each material component. In this study, hybrid fibrous scaffolds composed of synthetic P(LLA-CL) elastomeric and naturally derived fibrinogen protein were fabricated and characterized for their bioactive and physiochemical properties. Fiber diameters of hybrid scaffolds increased with increasing P(LLA-CL) content, and the shape of fibers changed from cylindrical shape on pure polymer scaffolds to flat structure on hybrid scaffolds. Characterizations of ATR-FTIR, XRD, and thermal properties indicated that the hybrid scaffolds contain two different phases, one composed of pure fibrinogen and the other corresponding to a mixture of fibrinogen and P(LLA-CL), and no obvious chemical reaction takes place between two components. The hybrid fibrous scaffolds showed tailorable degradation rates than pure P(LLA-CL) and higher mechanical properties than pure fibrinogen, and both tensile strength and breaking strain increased with increasing P(LLA-CL) content. In Vitro studies revealed that L929 cells on hybrid scaffolds achieved relatively higher level of cell attachment after 12 h of culture and significant increased cell proliferation rate after 7 days of culture, when compared with pure fibrinogen and P(LLA-CL) scaffolds, and the cells exhibited a spreading polygonal shape on the hybrid fibrous surfaces compared to a round shape on surfaces of pure polymer scaffolds. Therefore, the fibrinogen/P(LLA-CL) hybrid fibrous scaffolds possess the combined benefits of each individual component, which make it capable as scaffolds for soft tissue reconstruction.

  4. Copper and homocysteine in cardiovascular diseases.

    PubMed

    Kang, Y James

    2011-03-01

    High blood copper (Cu) and homocysteine (Hcy) concentrations have been independently reported as risk factors for cardiovascular diseases. When they are simultaneously measured, a concomitant increase in both parameters in association with vascular dysfunction has been observed. Cu chelator penicillamine can significantly diminish the inhibitory effect of Hcy on endothelial function, which has led to the interpretation that Cu mediates the deleterious effect of Hcy. However, Cu itself has been shown to be beneficial to the cardiovascular system. In particular, Cu promotion of angiogenesis has been well documented. Cu stimulates endothelial cell proliferation and differentiation and promotes microtubule formation in cultured saphenous veins. High levels of Hcy do not affect the process of microtubule formation, but the combination of Cu and Hcy leads to a significant inhibitory effect. Under other conditions, Cu does not affect, but Hcy inhibits, the endothelium-dependent relaxation of blood vessels and the combination of both augments the inhibition. Why does Cu produce adverse effects when it co-exists with Hcy? Cu forms complexes with Hcy and the Cu-Hcy complexes possess a deleterious potential due to their redox properties. Cu chelation can remove Cu from the Cu-Hcy complexes, but leaves behind high levels of Hcy and produces Cu deficiency. An alternative approach should focus on the reduction of Hcy, but maintenance of Cu, making detrimental Cu beneficial. A comprehensive understanding of Cu speciation and a development of selective modulation of Cu coordination to Cu-binding molecules to avoid Cu-Hcy complex formation would effectively improve the condition of cardiovascular disease.

  5. Dietary homocysteine promotes atherosclerosis in apoE-deficient mice by inducing scavenger receptors expression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Elevated plasma homocysteine (Hcy) levels have been recognized as an independent risk factor for cardiovascular and cerebrovascular diseases. However, the causative mechanisms have not been delineated. Scavenger receptors such as scavenger receptor-AI/II (SR-A), CD36, and lectin-like oxidized LDL ...

  6. Public health significance of elevated homocysteine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Homocysteine is a sulfur amino acid whose metabolism stands at the intersection of two pathways: remethylation, which requires folic acid and vitamin B12 coenzymes; and transsulfuration, which requires pyridoxal-5'-phosphate, the vitamin B6 coenzyme. Data from a number of laboratories suggest that m...

  7. Effects of Fibrinogen Concentrate on Thrombin Generation, Thromboelastometry Parameters, and Laboratory Coagulation Testing in a 24-Hour Porcine Trauma Model

    PubMed Central

    Zentai, Christian; Solomon, Cristina; van der Meijden, Paola E. J.; Spronk, Henri M. H.; Schnabel, Jonas; Rossaint, Rolf

    2015-01-01

    Introduction: In a 24-hour porcine model of liver injury, we showed that fibrinogen supplementation does not downregulate endogenous fibrinogen synthesis. Here we report data from the same study showing the impact of fibrinogen on coagulation variables. Materials and Methods: Coagulopathy was induced in 20 German land race pigs by hemodilution and blunt liver injury. Animals randomly received fibrinogen concentrate (100 mg/kg) or saline. Coagulation parameters were assessed and thromboelastometry (ROTEM) was performed. Results: Fibrinogen concentrate significantly reduced the prolongations of EXTEM clotting time, EXTEM clot formation time, and prothrombin time induced by hemodilution and liver injury. A decrease in clot strength was also ameliorated. Endogenous thrombin potential was significantly higher in the fibrinogen group than in the control group, 20 minutes (353 ± 24 vs 289 ± 22 nmol/L·min; P < .05) and 100 minutes (315 ± 40 vs 263 ± 38 nmol/L·min; P < .05) after the start of infusion. However, no significant between-group differences were seen in other thrombin generation parameters or in d-dimer or thrombin–antithrombin levels. Fibrinogen–platelet binding was reduced following liver injury, with no significant differences between groups. No significant between-group differences were observed in any parameter at ∼12 and ∼24 hours. Conclusion: This study suggests that, in trauma, fibrinogen supplementation may shorten some measurements of the speed of coagulation initiation and produce a short-lived increase in endogenous thrombin potential, potentially through increased clotting substrate availability. Approximately 12 and 24 hours after starting fibrinogen concentrate/saline infusion, all parameters measured in this study were comparable in the 2 study groups. PMID:25948634

  8. Regulation of fibrinogen receptor expression on human platelets

    SciTech Connect

    Shattil, S.J.; Motulsky, H.J.; Insel, P.A.; Brass, L.F.

    1986-03-01

    Platelet aggregation requires the binding of fibrinogen to specific receptors on the plasma membrane glycoprotein IIb-IIIa complex. Although the IIb-IIIa complex is identifiable on the surface of resting platelets, the fibrinogen receptor is expressed only after platelet activation. The authors have developed a monoclonal anti-IIb-IIIa antibody (PAC-1) that binds only to stimulated platelets and only in the presence of Ca. In order to better understand the steps leading to platelet aggregation, the authors used radiolabeled PAC-1 and fibrinogen to examine the effect of the ..cap alpha../sub 2/-adrenergic agonist, epinephrine, on the expression and function of the fibrinogen receptor. The addition of epinephrine to unstirred platelets caused and immediate increase in PAC-1 and fibrinogen binding that was associated with platelet aggregation once the platelets were stirred. Even after prolonged incubation of the platelets with epinephrine, fibrinogen receptor expression could be reversed by adding EGTA, PGl/sub 2/, or the ..cap alpha../sub 2/-adrenergic antagonist, phentolamine. When unstirred platelets were exposed to epinephrine for more than 10 min, the extent of aggregation caused by subsequent stirring was decreased by 70%. Surprisingly, these desensitized platelets bound PAC-1 and fibrinogen normally, indicating that the loss of aggregation was not due to a decrease in fibrinogen receptor expression or function. These studies demonstrate that: (1) fibrinogen receptor expression is dependent on extracellular CA; (2) induction of the fibrinogen receptor by epinephrine requires the continued presence of the agonist; and (3) prolonged stimulation of the platelet by epinephrine can lead to a reduced aggregation response by a mechanism that does not involve a loss of either fibrinogen recepor expression or fibrinogen binding.

  9. Antimicrobial activity of fibrinogen and fibrinogen-derived peptides--a novel link between coagulation and innate immunity.

    PubMed

    Påhlman, L I; Mörgelin, M; Kasetty, G; Olin, A I; Schmidtchen, A; Herwald, H

    2013-05-01

    Fibrinogen is a key player in the blood coagulation system, and is upon activation with thrombin converted into fibrin that subsequently forms a fibrin clot. In the present study, we investigated the role of fibrinogen in the early innate immune response. Here we show that the viability of fibrinogen-binding bacteria is affected in human plasma activated with thrombin. Moreover, we found that the peptide fragment GHR28 released from the β-chain of fibrinogen has antimicrobial activity against bacteria that bind fibrinogen to their surface, whereas non-binding strains are unaffected. Notably, bacterial killing was detected in Group A Streptococcus bacteria entrapped in a fibrin clot, suggesting that fibrinogen and coagulation is involved in the early innate immune system to quickly wall off and neutralise invading pathogens.

  10. Homocysteine-Mediated Modulation of Mitochondrial Dynamics in Retinal Ganglion Cells

    PubMed Central

    Ganapathy, Preethi S.; Perry, Richard L.; Tawfik, Amany; Smith, Robert M.; Perry, Elizabeth; Roon, Penny; Bozard, B. Renee; Ha, Yonju

    2011-01-01

    Purpose. To evaluate the effect of excess homocysteine on the regulation of retinal ganglion cell mitochondrial dynamics. Methods. Mice deficient in cystathionine-β-synthase (cbs) were used as a model of hyperhomocysteinemia. Gene and protein expression analyses of Opa1 and Fis1 were performed on cbs+/−neural retinas. Mitochondria within retinal ganglion cell axons underwent systematic ultrastructural analysis to measure area, length, width, and the distance between the mitochondria and the axon wall. Primary mouse ganglion cells were cultured, treated with homocysteine, and assessed for levels of Opa1 and Fis1 protein, the number of mitochondria per length of neurite, and levels of cleaved caspase-3. Results. Opa1 and Fis1 protein levels in cbs+/− neural retinas were elevated to 191.00% ± 26.40% and 226.20% ± 4.57%, respectively, compared with wild-type. Mitochondria of cbs+/− retinas were smaller in all parameters studied, including area (0.32 ± 0.01μm2 vs. 0.42 ± 0.02 μm2), compared with wild-type. Primary ganglion cells treated with homocysteine had elevations in Opa1 and Fis1 proteins, a significantly higher number of mitochondria per length of neurite (0.1781 ± 0.017 vs. 0.1156 ± 0.012), and significantly higher levels of cleaved caspase-3 compared with control. Conclusions. This study provides the first evidence that homocysteine-induced ganglion cell loss involves the dysregulation of mitochondrial dynamics, both in vivo and in vitro. The present data suggest increased mitochondrial fission as a novel mechanism of homocysteine toxicity to neurons. Of particular relevance are glaucoma and Alzheimer's disease, neurodegenerative diseases that are associated with hyperhomocysteinemia and, more recently, have implicated increased mitochondrial fission in their pathogeneses. PMID:21642619

  11. Single-molecule surface studies of fibrinogen and DNA on semiconductors

    NASA Astrophysics Data System (ADS)

    Kong, Xianhua

    Understanding of protein adsorption onto non-biological substrates is of fundamental interest in science, but also has great potential technological applications in medical devices and biosensors. This study explores the non-specific interaction, at the single molecule level, of a blood protein and DNA with semiconductor surfaces through the use of a custom built, non rastering electron emission microscope and a scanning probe microscope. The specifics and history of electron emission are described as well as the equipment used in this study. The protein examined in this study is human plasma fibrinogen, which plays an important role in haemostatis and thrombosis, and deoxyribonucleic acid (DNA) is also studied. A novel technique for determining the photothreshold of biomolecules on single molecule level is developed and applied to fibrinogen molecules adsorbed on oxidized silicon surfaces, using photo-electron emission microscopy (PEEM). Three theoretical models are employed and compared to analyze the experimental photothreshold data. The non-specific adsorption of human plasma fibrinogen on oxidized p- and n- type silicon (100) surfaces is investigated to characterize both hydrophobic interactions and electrostatic forces. The experimental results indicate that hydrophobic interactions are one of the driving forces for protein adsorption and the electrostatic interactions also play a role in the height of the fibrinogen molecules adsorbed on the surface. PEEM images establish a photo threshold of 5.0 +/- 0.2 eV for fibrinogen on both n-type and p-type Si (100) surfaces. We suggest that the photothreshold results from surface state associated Fermi level (EF) pinning and there exists negative charge transfer from the adsorbed fibrinogen onto the p-type silicon substrates, while on n-type silicon substrates negative charge is transferred in the opposite direction. The adsorption of deoxyribonucleic acid (DNA) on mica and silicon is studied in liquid and ambient

  12. In vitro formation and i vivo clearance of fibrinogen: fibrin complexes.

    PubMed

    Sherman, L A; Harwig, S; Lee, J

    1975-07-01

    Fbrinogen:fibrin complexes have been previously described in various thrombotic disorders. To evaluate further the properties of fibrinogen:fibrin complexes, and theirin vitro and in vivo behavior, soluable fibrinogen:fibrin complexes have been formed invitro using mixtures of '131l-fibrinogen ('131l-F) and '125l-fibrin ('125l-fb). By means of Sepharose 4B chromatography, a macromolecular complex (peak one) containing both moieties could be separated from a lower molecular weight peak two containg noncomplexed material. The latter eluted at the same position as did intact fibrogen. Both the '131l-F and '125l-fb components of peak one were rapidly catabolized when injected into rabbits with residual blood activity at 24 hours of 8 per cent and 4 per cent, respectively. Peak two behavedas a simple mixture with corresponding 24-hour levels at 31 per cent and 3 per cent. Gel filtration of postinjuection plasma samples demonstrated that peak one remained as macromolecular complex. Preinjection crosslinking of the F:fb complex with factor xiii did not substantially change the blood clearance. Prior blockage of the reticuloendotheial system with Thorotrast or carbon resulted in impaired clearance of peak one. The data provide evidence that fibrinogen and fibrin can form a macromolecular complex which is stable both in vitro and vivo. Further, the reticuloendotheialsystem was shown to mediate the the in vivo clearance of this complex. This latterfinding may be of pathophysiologic significance.

  13. Sequence of Fibrinogen Proteolysis and Platelet Release after Intrauterine Infusion of Hypertonic Saline

    PubMed Central

    Nossel, H. L.; Wasser, J.; Kaplan, K. L.; Lagamma, K. S.; Yudelman, I.; Canfield, R. E.

    1979-01-01

    Plasma fibrinopeptide B (Bβ1-14 or FPB) immunoreactivity was studied by radioimmunoassay in patients who received intrauterine infusion of hypertonic saline to terminate pregnancy. FPB immunoreactivity increased with thrombin treatment (TIFPB) suggesting the presence of a larger FPB-containing peptide, since purified FPB is not altered by thrombin, whereas thrombin increases the immunoreactivity of Bβ1-42 (which includes FPB) 10-fold. TIFPB immunoreactivity in plasma, drawn 4 h after hypertonic saline infusion eluted from Sephadex G-50 similarly to isolated Bβ1-42. Streptokinase, incubated with normal plasma progressively generated TIFPB immunoreactivity, which showed a major component which eluted from Sephadex G-50 similarly to Bβ1-42. Streptokinase generated TIFPB much more rapidly in reptilase-treated plasma that contains fibrin I, (which still includes FPB), indicating that fibrin I is preferred over fibrinogen as a substrate for plasmin cleavage of arginine (Bβ42)-alanine (Bβ43). Serial studies were then made in 10 patients receiving intrauterine hypertonic saline. Fibrinopeptide A (FPA) levels rose immediately, reached a peak between 1 and 2 h, were declining at 4 h, and were normal at 24 and 48 h. TIFPB levels rose slightly in the 1st h, reached a peak at 4 h, and had returned to base-line values at 24 h. Serum fibrinogen degradation product levels were unchanged at 1 h, reached their highest level at 4 h, and were still markedly elevated at 24 and 48 h. Fibrinogen levels dropped slightly being lowest at 4 and 24 h. Platelet counts declined in parallel with the fibrinogen levels over the first 4 h, but continued to decrease through 48 h. Beta thromboglobulin (βTG) levels generally paralleled FPA levels whereas platelet factor 4 (PF4) levels showed only slight changes. The data indicate that immediately after intrauterine hypertonic saline infusion thrombin is formed that cleaves FPA from fibrinogen to produce fibrin I and releases βTG and PF4 from

  14. Folate and homocysteine metabolisms and their roles in the biochemical basis of neuropsychiatry.

    PubMed

    Coşar, Alpaslan; Ipçioğlu, Osman Metin; Ozcan, Omer; Gültepe, Mustafa

    2014-01-01

    The term 'one-carbon metabolism' is commonly used to describe 3 separate metabolic processes: folate metabolism, the homocysteine remethylation cycle, and the transsulfuration pathway. Folate metabolism concerns the biochemical reactions in which endogenous and exogenous one-carbon units are transferred to tetrahydrofolates. The remethylation cycle is used for the synthesis of methionine from homocysteine with one-carbon units that come from folate. This methionine is thenfused for the synthesis of S-adenosyl methionine, which is a general donor of methyl groups for many biochemical reactions in the human body. In the transsulfuration pathway, some amino acids and polypeptides, such as cystathionine, cysteine, and glutathione, are synthesized from homocysteine. The kinetics of the enzymes in this pathway are regulated by the substrates of the remethylation cycle. The methylation process has been thought to have an important role in the biochemical basis of neuropsychiatry. An elevated homocysteine level is the most important marker of folate and vitamin B12 deficiencies, and also the most reliable biochemical sign of functional insufficiency. Some neurological and neuropsychiatric diseases, such as psychosis, Alzheimer's disease, and autism, have been found to be related to disorders of one-carbon metabolism. This review aims to summarize both one-carbon metabolism and its relationships with neuropsychiatric disorders.

  15. Liquid chromatographic determination of total homocysteine in blood plasma with photometric detection.

    PubMed

    Zhloba, Alexander A; Blashko, Eduard L

    2004-02-01

    A rapid and sensitive method for quantification of homocysteine total forms and glutathione levels in blood plasma via HPLC was developed. Dithiotreitol as a water soluble agent has been used as a reductant for both protein and nonprotein disulphides. Dithiotreitol reacts with the mixed disulphides under 60 degrees C treatment within 10 min. Reduced aminothiols and homocystein were easily derivated with 5,5'-dithiobis-(2-nitrobenzoic acid) and the resultant ultraviolet absorbance within 330 nm was detected by the HPLC method. The concentration of total plasma homocysteine was significantly higher in groups of patients: with the end stage of renal disease: 45.5+/-40.9 micromol/l (n=79), with cerebral vascular disorders 12.3+/-7.0 micromol/l (n=65), and with coronary atherosclerosis 15.4+/-10.9 micromol/l (n=15) than that in healthy subjects (6.2+/-1.74 micromol/l, n=20). Some major advantages of the method include: simultaneous measurement of both total homocysteine and total glutathione, no loss of oxidized form during processing of blood plasma for aminothiols measurement, use of protein-bound aminothiols solution as a calibrator.

  16. Serum homocysteine as a risk factor for carotid intimal thickening in acute stroke: A cross sectional observational study

    PubMed Central

    Devasia, Anup J.; Joy, Binu; Tarey, Subhash D.

    2016-01-01

    Introduction: The present study aimed to analyse if there is a correlation between carotid intima medial thickening (CIMT) and Hcy in stroke patients. Methodology: We studied 100 consecutive cases of acute anterior circulation strokes at St. John's Medical College, Bangalore, India. Fasting serum samples for homocysteine were sent within 24 hours of admission and all patients underwent a carotid Doppler scan and carotid intima-medial thickness (CIMT) was estimated on both sides. Results: There was significant correlation between serum homocysteine levels and carotid intima-medial thickness (r = 0.409, p = 0.000). Also after controlling for other possible risk factors it was found that elevations in serum homocysteine levels would cause a variation of 60% in the carotid intima-medial thickening. Conclusion: Serum Hcy levels correlate well with CIMT and hence may predict atherothrombotic events. PMID:27011628

  17. A novel natural mutation AαPhe98Ile in the fibrinogen coiled-coil affects fibrinogen function.

    PubMed

    Riedelová-Reicheltová, Zuzana; Kotlín, Roman; Suttnar, Jiří; Geierová, Véra; Riedel, Tomáš; Májek, Pavel; Dyr, Jan Evangelista

    2014-01-01

    The aim of this study was to investigate the structure and function of fibrinogen obtained from a patient with normal coagulation times and idiopathic thrombophilia. This was done by SDS-PAGE and DNA sequence analyses, scanning electron microscopy, fibrinopeptide release, fibrin polymerisation initiated by thrombin and reptilase, fibrinolysis, and platelet aggregometry. A novel heterozygous point mutation in the fibrinogen Aα chain, Phe98 to Ile, was found and designated as fibrinogen Vizovice. The mutation, which is located in the RGDF sequence (Aα 95-98) of the fibrinogen coiled-coil region, significantly affected fibrin clot morphology. Namely, the clot formed by fibrinogen Vizovice contained thinner and curled fibrin fibers with reduced length. Lysis of the clots prepared from Vizovice plasma and isolated fibrinogen were found to be impaired. The lysis rate of Vizovice clots was almost four times slower than the lysis rate of control clots. In the presence of platelets agonists the mutant fibrinogen caused increased platelet aggregation. The data obtained show that natural mutation of Phe98 to Ile in the fibrinogen Aα chain influences lateral aggregation of fibrin protofibrils, fibrinolysis, and platelet aggregation. They also suggest that delayed fibrinolysis, together with the abnormal fibrin network morphology and increased platelet aggregation, may be the direct cause of thrombotic complications in the patient associated with pregnancy loss. PMID:24108601

  18. Homocysteine, B Vitamins, and Cognitive Impairment.

    PubMed

    Smith, A David; Refsum, Helga

    2016-07-17

    Moderately elevated plasma total homocysteine (tHcy) is a strong modifiable risk factor for vascular dementia and Alzheimer's disease. Prospectively, elevated tHcy is associated with cognitive decline, white matter damage, brain atrophy, neurofibrillary tangles, and dementia. Most homocysteine-lowering trials with folate and vitamins B6 and/or B12 tested as protective agents against cognitive decline were poorly designed by including subjects unlikely to benefit during the trial period. In contrast, trials in high-risk subjects, which have taken into account the baseline B vitamin status, show a slowing of cognitive decline and of atrophy in critical brain regions, results that are consistent with modification of the Alzheimer's disease process. Homocysteine may interact with both risk factors and protective factors, thereby identifying people at risk but also providing potential strategies for early intervention. Public health steps to slow cognitive decline should be promoted in individuals who are at risk of dementia, and more trials are needed to see if simple interventions with nutrients can prevent progression to dementia. PMID:27431367

  19. [HOMOCYSTEINE AS A PROGNOSTIC MARKER OF ATRIAL REMODELING AND CLINICAL PICTURE IN PATIENTS WITH PAROXYSMAL AND PERSISTENT FORMS OF ATRIAL FIBRILLATION].

    PubMed

    Snezhitsky, V A; Yatskevich, E S; Doroshenko, E M; Smirnov, V Yu; Dolgoshey, T S; Rubinsky, A Yu

    2016-01-01

    The aim of this work was to study prognostic significance of the relationship between the homocysteine level, structural/functional atrial remodeling, and clinical picture of paroxysmal and persistent forms of atrial fibrillation (AF). The study included 75 patients with AF concomitant with coronary heart disease and hypertensive disease without apparent structural changes in myocardium. Group 1 was comprised of 48 patients with paroxysmal AF, group 2 of 27 patients with persistent AF. 19 patients with coronary heart disease and hypertensive disease without AF served as controls. The structural and functional state of the heart was evaluated based on two-dimensional trans-thoracal echocardiography with the use of the formulas for calculating left ventricular characteristics. Blood homocysteine levels were measured The frequency of AF relapses was determined after an 1 year follow-up. The homocysteine level over 11.2 mcmol/l was related to left ventricle enlargement (over 40 mm), high frequency and relapse rate of AF. It is concluded that the relationship between homocysteine levels, left ventricle size, frequency and relapse rate of AF suggests the influence of homocysteine on atrial remodeling. A rise in the homocysteine level above 11 mcmol/l should be regarded as a prognostic factor of increased AF relapse rate. PMID:27172716

  20. Study on relationships among deep vein thrombosis, homocysteine & related B group vitamins

    PubMed Central

    Ekim, Meral; Ekim, Hasan; Yilmaz, Yunus Keser; Kulah, Bahadir; Polat, M. Fevzi; Gocmen, A. Yesim

    2015-01-01

    Objectives: Hyperhomocysteinemia has been considered as a potential risk factor for deep venous thrombosis (DVT) but it is still controversy. We aimed to evaluate the prevalence of hyperhomocysteinemia in patients with DVT. Our second objective was to document the prevalence of folate, Vitamin B6, and Vitamin B12 level in this patient population. Methods: Sixty patients with DVT aged from 23 to 84 years, were assessed regarding demographic characteristics, serum levels of homocysteine, folate, vitamin B12, and vitamin B6. The diagnosis of DVT was based upon Wells scoring system and serum D-dimer level and confirmed by deep venous Doppler ultrasonography of the lower limbs. Results: Mean serum homocysteine levels were found significantly higher in patients over the age of 40 years (10.81±4.26 µmol/L vs 9.13±3.23 µmol/L). Of all the patients, 9 patients had homocysteine level above the 15µmol/L, 26 had folic acid level below 3 ng/ml, one had vitamin B12 level below 150 pmol/L, and two had vitamin B6 level below 30 nmol/L. In the hyperhomocysteinemic group, five patients had low folic acid level, one had low vitamin B12 level, and two had low vitamin B6 level. Conclusions: Hyperhomocysteinemia, in women older than 40 years, may be a risk factor for DVT. Folic acid deficiency may also influence serum homocysteine concentrations. Folate therapy may be offered to the patients with DVT. However further studies are required to clarify the underlying molecular mechanisms. PMID:26101499

  1. Plasmic degradation of fibrinogen Paris I.

    PubMed

    Budzynski, A Z; Marder, V J

    1976-11-01

    Fibrin obtained from the plasma of a patient having abnormal fibrogen Paris I contains normal alpha, beta, and gamma polypeptide chains as well as an abnormal gamma-chain (gammaParis I) of approximately 51,000 daltons molecular weight. Plasmic digestion of Paris I fibrogen and noncrosslinked fibrin yields both normal and abnormal Fragment D molecules, the latter having a higher negative charge and molecular weight than that liberated from normal fibrinogen and noncorsslinked fibrin. After disulfide bond reduction, an abnormal polypeptide chain of approximately 40,500 +/- 2,000 daltons molecular weight was demonstrated in the Paris I digests by dodecyl sulfate (SDS) polyacrylamide gel electrophoresis. Comparison with the electrophoretic pattern for reduced digests of normal substrates indicates that it is a gamma-chain remnant in the normal Fragment D. Although the carbohydrate content in the gamma-Paris I-chain is slightly higher than that in the normal gamma-chain, as measured by periodic acid-Schiff reagent (PAS) staining intensity, it is concluded that extra carbohydrate does not account for the high molecular weight of the gamma-Paris I-chain since the 40,500 dalton chain does not stain with PAS. Plasma digestion of Paris I crosslinked fibrin yields a large amount of Fragment D in addition to Fragment D-D ("D-dimer") and E molecules, in contrast to a digest of normal crosslinked fibrin, from which only the latter two fragments are formed. This finding suggests that the defect in fibrinogen Paris I derives from an abnormality in the carboxy-terminal region of the gammaParis I-chain, so that in the presence of Factor XIII, these chains are not crosslinked and Fragment D-D molecules are not liberated upon subsequent plasmic degradation. The data provide support for the previous conclusion that a longer than normal polypeptide chain sequence at the carboxy-terminal portion of the gammaParis I-chains accounts for the increased size of these chains relative to the

  2. Clinical use and rational management of homocysteine, folic acid, and B vitamins in cardiovascular and thrombotic diseases.

    PubMed

    Stanger, O; Herrmann, W; Pietrzik, K; Fowler, B; Geisel, J; Dierkes, J; Weger, M

    2004-06-01

    About half of all deaths are due to cardiovascular disease and its complications. The economic burden on society and the healthcare system from cardiovascular disability, complications, and treatments is huge and becoming larger in the rapidly aging populations of developed countries. As conventional risk factors fail to account for part of the cases, homocysteine, a "new" risk factor, is being viewed with mounting interest. Homocysteine is a sulfur-containing intermediate product in the normal metabolism of methionine, an essential amino acid. Folic acid, vitamin B(12), and vitamin B(6) deficiency and reduced enzyme activities inhibit the breakdown of homocysteine, thus increasing the intracellular homocysteine concentration. Numerous retrospective and prospective studies have consistently found an independent relationship between mild hyperhomocysteinemia and cardiovascular disease or all-cause mortality. Starting at a plasma homocysteine concentration of approximately 10 micromol/l, the risk increase follows a linear dose-response relationship with no specific threshold level. Hyperhomocysteinemia as an independent risk factor for cardiovascular disease is thought to be responsible for about 10 percent of total risk. Elevated plasma homocysteine levels (> 12 micromol/l; moderate hyperhomocysteinemia) are considered cytotoxic and are found in 5 to 10 percent of the general population and in up to 40 percent of patients with vascular disease. Additional risk factors (smoking, arterial hypertension, diabetes, and hyperlipidemia) may additively or, by interacting with homocysteine, synergistically (and hence overproportionally) increase overall risk. Hyperhomocysteinemia is associated with alterations in vascular morphology, loss of endothelial antithrombotic function, and induction of a procoagulant environment. Most known forms of damage or injury are due to homocysteine-mediated oxidative stresses. Especially when acting as direct or indirect antagonists of

  3. Changes in fibrinogen availability and utilization in an animal model of traumatic coagulopathy

    PubMed Central

    2013-01-01

    Background Impaired haemostasis following shock and tissue trauma is frequently detected in the trauma setting. These changes occur early, and are associated with increased mortality. The mechanism behind trauma-induced coagulopathy (TIC) is not clear. Several studies highlight the crucial role of fibrinogen in posttraumatic haemorrhage. This study explores the coagulation changes in a swine model of early TIC, with emphasis on fibrinogen levels and utilization of fibrinogen. Methods A total of 18 landrace pigs were anaesthetized and divided into four groups. The Trauma-Shock group (TS) were inflicted bilateral blast femoral fractures with concomitant soft tissue injury by a high-energy rifle shot to both hind legs, followed by controlled exsanguination. The Shock group (S) was exposed to shock by exsanguination, whereas a third group was exposed to trauma only (T). A fourth group (C) served as control. Physiological data, haematological measurements, blood gas analyses and conventional coagulation assays were recorded at baseline and repeatedly over 60 minutes. Thrombelastometry were performed by means of the tissue factor activated ExTEM assay and the platelet inhibiting FibTEM assay. Data were statistically analysed by repeated measurements analyses method. Results A significant reduction of fibrinogen concentration was observed in both the TS and S groups. INR increased significantly in the S group and differed significantly from the TS group. Maximum clot firmness (MCF) of the ExTEM assay was significantly reduced over time in both TS and S groups. In the FibTEM assay a significant shortening of the clotting time and an increase in MCF was observed in the TS group compared to the S group. Conclusion Despite a reduction in clotting capability measured by ExTEM MCF and a reduced fibrinogen concentration, extensive tissue trauma may induce an increased fibrin based clotting activity that attenuates the hypocoagulable tendency in exsanguinated animals. PMID

  4. Homocysteine lowering for stroke prevention: Unravelling the complexity of the evidence.

    PubMed

    Spence, J David

    2016-10-01

    Elevated levels of total homocysteine impair endothelial dysfunction and increase thrombosis. Homocysteine is causal in animal models, and in human studies, elevated total homocysteine is significantly associated with carotid atherosclerosis, lacunar infarction, and markedly increased risk of stroke in atrial fibrillation. Because two of the early large trials of B vitamin therapy (Vitamin Intervention for Stroke Prevention and the Norwegian Vitamin Study) did not show any reduction of stroke, and the Heart Outcomes Prevention Evaluation 2 trial was mistakenly interpreted as not showing a reduction of stroke (because the authors could not think of a biological difference between stroke and myocardial infarction), there has been widespread pessimism regarding treatment to lower total homocysteine for stroke prevention. However, the Heart Outcomes Prevention Evaluation 2 trial, the French trial of folic acid and omega three oils, the Vitamins to Prevent Stroke subgroup excluding antiplatelet therapy all showed a significant reduction of stroke. Reasons why the Vitamin Intervention for Stroke Prevention trial were negative included folate fortification in North America, provision of injections of B12 to patients with low baseline serum B12, and as it turns out, harm from cyanide in cyanocobalamin among participants with impaired renal function. In the Diabetic Intervention with Vitamins in Nephropathy trial, B vitamins including cyanocobalamin were harmful, and in a Vitamin Intervention for Stroke Prevention subgroup excluding participants who received B12 injections and those with impaired renal function, there was a statistically significant reduction of stroke/myocardial infarction/vascular death. In 2015, the China Stroke Primary Prevention Trial (CSPPT), in over 20,000 participants followed for 5 years, showed a significant reduction of stroke with folic acid in a setting where folate fortification has not been implemented. In the setting of folate fortification

  5. Effect of Vitamin B12 supplementation on serum homocysteine in patients undergoing hemodialysis: A randomized controlled trial.

    PubMed

    Tayebi, Ali; Biniaz, Vajihe; Savari, Samira; Ebadi, Abbas; Shermeh, Mahdi Sadeghi; Einollahi, Behzad; Rahimi, Abolfazl

    2016-03-01

    Clinical studies have shown that hyper-homocysteinemia is a potent independent risk factor for cardiovascular diseases, and many different methods have been investigated for lowering it in hemodialysis (HD) patients. Our study investigated the effect of Vitamin B 12 supplementation on serum homocysteine levels in these patients. This randomized trial was conducted on 140 HD patients. They were randomly distributed by lottery method into two groups: intervention and control. In the intervention group, 100 μg/mL of Vitamin B 12 was intravenously injected two times a week, for eight weeks. No intervention was performed in the control group. Serum levels of homocysteine, hemoglobin (Hb), and hematocrit (Hct) were measured at the beginning and again after eight weeks (2 months) of treatment. About 91% of the patients had hyperhomocysteinemia (serum homocysteine >15 μmol/L). The median baseline levels of serum homocysteine in the intervention and control groups were 31.9 and 26.9 μmol/L, respectively (P = 0.1). After eight weeks, the median homocysteine level reduced significantly in the Vitamin B 12 group to 22.2 versus 28.4 μmol/L in control group (P = 0.006). The mean Hb and Hct also changed significantly during our study (12.3 vs. 11.4 g/dL; P = 0.003 and 37.9 vs. 35.3%; P = 0.02, respectively). Our results demonstrated the existence of a statistical negative relationship between Vitamin B 12 and serum levels of homocysteine. Detailed investigations with larger sample sizes and longer-term use of Vitamin B 12 are recommended. PMID:26997378

  6. Fibrinogen-Related Proteins (FREPs) in Mollusks.

    PubMed

    Adema, Coen M

    2015-01-01

    Anti-parasite responses of the snail Biomphalaria glabrata involve antigen-reactive plasma lectins termed fibrinogen-related proteins (FREPs) comprising a C-terminal fibrinogen (FBG) domain and one or two upstream immunoglobulin domains. FREPs are highly polymorphic; they derive from several gene families with multiple loci and alleles that are diversified by exon loss, alternative splicing, and random somatic mutation (gene conversion and point mutations). Individual B. glabrata snails have dynamically distinct FREP sequence repertoires. The immune relevance of B. glabrata FREPs is indicated by FREP binding to polymorphic antigens of (snail-specific) digenean parasites and altered resistance of B. glabrata to digeneans following RNAi knockdown of FREPs. The compatibility polymorphism hypothesis proposes that FREP mutation increases the range of germline-encoded immune recognition in B. glabrata to counter antigenically-varied parasites. Somatic mutation may result from sequence exchange among tandemly arranged FREP genes in the genome, and analysis of sequence variants also suggests involvement of cytidine deaminase-like activity or epigenetic regulation. Without current indications of selection or retention of effective sequence variants toward immunological memory, FREP diversification is thought to afford B. glabrata immunity that is anticipatory but not adaptive. More remains to be learned about this system; other mollusks elaborate diversified lectins consisting of single FBG domains, and bona fide FREPs were reported from additional gastropod species, but these may not be diversified. Future comparative immunological studies and gene discovery driven by next-generation sequencing will further clarify taxonomic distribution of FREP diversification and the underlying mutator mechanisms as a component of immune function in mollusks. PMID:26537379

  7. Ultrastructural and biochemical analysis of fibrinogen receptors on activated thrombocytes

    SciTech Connect

    O'Toole, E.T.

    1989-01-01

    The present studies have been concerned with the role of fibrinogen and its receptor, GP IIb/IIIa, during the activation and early aggregation of pigeon thrombocytes. Thrombocytes were surface labeled with {sup 125}I then separated on SDS-PAGE. Analysis by gel autoradiography revealed major bands at MW 145 kd and 98 kd, which corresponded to human GPIIb and GPIIIa. Immunologic similarity of the pigeon and human receptor components was established by dot blot analysis using polyclonal antibodies directed against human GPIIb and GPIIIa. Pigeon fibrinogen, isolated by plasma precipitation with PEG-1000 and purified over Sepharose 4B, was used to study receptor-ligand interaction. Separation of pigeon fibrinogen on SDS-PAGE resulted in three peptides having apparent MW of 62kd, 55kd, and 47kd which are comparable to human fibrinogen. Further similarity of human and pigeon fibrinogen was verified by immonodiffusion against an antibody specific for the human protein. The role of fibrinogen and its receptor in thrombocyte function was established by turbidimetric aggregation using thrombin as an agonist under conditions requiring Ca++ and fibrinogen.

  8. Developmental expression and organisation of fibrinogen genes in the zebrafish.

    PubMed

    Fish, Richard J; Vorjohann, Silja; Béna, Frédérique; Fort, Alexandre; Neerman-Arbez, Marguerite

    2012-01-01

    The zebrafish is a model organism for studying vertebrate development and many human diseases. Orthologues of the majority of human coagulation factors are present in zebrafish, including fibrinogen. As a first step towards using zebrafish to model human fibrinogen disorders, we cloned the zebrafish fibrinogen cDNAs and made in situ hybridisations and quantitative reverse transcription-polymerase chain reactions (qRT-PCR) to detect zebrafish fibrinogen mRNAs. Prior to liver development or blood flow we detected zebrafish fibrinogen expression in the embryonic yolk syncytial layer and then in the early cells of the developing liver. While human fibrinogen is encoded by a three-gene, 50 kilobase (kb) cluster on chromosome 4 ( FGB-FGA-FGG ), recent genome assemblies showed that the zebrafish fgg gene appears distanced from fga and fgb , which we confirmed by in situ hybridisation. The zebrafish fibrinogen Bβ and γ protein chains are conserved at over 50% of amino acid positions, compared to the human polypeptides. The zebrafish Aα chain is less conserved and its C-terminal region is nearly 200 amino acids shorter than human Aα. We generated transgenic zebrafish which express a green fluorescent protein reporter gene under the control of a 1.6 kb regulatory region from zebrafish fgg . Transgenic embryos showed strong fluorescence in the developing liver, mimicking endogenous fibrinogen expression. This regulatory sequence can now be used for overexpression of transgenes in zebrafish hepatocytes. Our study is a proof-of-concept step towards using zebrafish to model human disease linked to fibrinogen gene mutations.

  9. Preparation of CuO/ZnO nanocomposite and its application as a cysteine/homocysteine colorimetric and fluorescence detector.

    PubMed

    Šimšíková, Michaela; Čechal, Jan; Zorkovská, Anna; Antalík, Marián; Šikola, Tomáš

    2014-11-01

    Cysteine and homocysteine play a crucial role in many biological functions but abnormal levels of these amino acids may lead to various forms of pathogenesis. Therefore, selective and easy-to-use methods for the detection of cysteine and homocysteine are essential for the early diagnosis of developing diseases. In this paper we report on a rapid, straightforward and highly selective method for the detection of cysteine (Cys) and homocysteine (Hcy) which uses a CuO/ZnO nanocomposite as a dual colorimetric and fluorometric assay. The presence of Cys and Hcy in a solution of these nanorods (NRs) induces a change in its color from light blue to dark grey which is visible to the naked eye. This is accompanied by a blue shift in the absorption spectra from 725 nm to 650 nm and a decrease in the intensity of CuO/ZnO nanocomposite emission. These changes are ascribed to the reduction of Cu(II) to Cu(0), and the oxidation of cysteine (homocysteine) and subsequent formation of the disulfide bond. This novel assay method does not respond to any other amino-acid which is present in living organisms; therefore the selective determination of cysteine (homocysteine) with a lower analyte limit of 40 μM (4.8 μg mL(-1)) can be carried out in aqueous solutions without the need for any sophisticated instrumentation, fluorophore molecules or complicated procedures.

  10. Preparation of CuO/ZnO nanocomposite and its application as a cysteine/homocysteine colorimetric and fluorescence detector.

    PubMed

    Šimšíková, Michaela; Čechal, Jan; Zorkovská, Anna; Antalík, Marián; Šikola, Tomáš

    2014-11-01

    Cysteine and homocysteine play a crucial role in many biological functions but abnormal levels of these amino acids may lead to various forms of pathogenesis. Therefore, selective and easy-to-use methods for the detection of cysteine and homocysteine are essential for the early diagnosis of developing diseases. In this paper we report on a rapid, straightforward and highly selective method for the detection of cysteine (Cys) and homocysteine (Hcy) which uses a CuO/ZnO nanocomposite as a dual colorimetric and fluorometric assay. The presence of Cys and Hcy in a solution of these nanorods (NRs) induces a change in its color from light blue to dark grey which is visible to the naked eye. This is accompanied by a blue shift in the absorption spectra from 725 nm to 650 nm and a decrease in the intensity of CuO/ZnO nanocomposite emission. These changes are ascribed to the reduction of Cu(II) to Cu(0), and the oxidation of cysteine (homocysteine) and subsequent formation of the disulfide bond. This novel assay method does not respond to any other amino-acid which is present in living organisms; therefore the selective determination of cysteine (homocysteine) with a lower analyte limit of 40 μM (4.8 μg mL(-1)) can be carried out in aqueous solutions without the need for any sophisticated instrumentation, fluorophore molecules or complicated procedures. PMID:25465753

  11. The functional effects of the -455G/A polymorphism on the IL-6-induced expression of the beta-fibrinogen gene may be due to linkage disequilibrium with other functional polymorphisms.

    PubMed

    Morozumi, Toshiya; Sharma, Ashu; De Nardin, Ernesto

    2009-01-01

    Elevated plasma fibrinogen levels have been identified as an independent risk factor for coronary heart diseases, stroke and peripheral artery disease. The -455G/A polymorphism in the promoter region of the beta-fibrinogen gene has been associated with increased plasma fibrinogen levels. However, the functional effect of this polymorphism has been controversial and other polymorphisms in the fibrinogen gene have also been implicated in higher fibrinogen levels. In this study, we evaluated the transcriptional activity of 4 natural haplotypes and 6 artificial haplotypes in the promoter region of the beta-fibrinogen gene. Significantly lower IL-6-induced activity was observed in the -1420A and -148T alleles. In contrast, the -854A allele had significantly higher activity. Artificial haplotypes containing the -1420A, -854A and -148T alleles were also analyzed to confirm individual functional effects. The -1420A and -148T alleles significantly lowered the activities, while the -854A allele significantly raised the activity. From this study we conclude that the -1420G/A, -854G/A and -148C/T polymorphisms in the beta-fibrinogen promoter region are functional polymorphisms while the -455G/A polymorphism may not be a functional one, and that the association of the -455G/A polymorphism with higher fibrinogen levels may actually be due to linkage disequilibrium between the -455G/A polymorphism and other truly functional polymorphisms.

  12. The molecular cloning and characteristics of a fibrinogen-related protein (TfFREP1) gene from roughskin sculpin (Trachidermus fasciatus).

    PubMed

    Chai, Yingmei; Yu, Shanshan; Zhu, Qian

    2012-09-01

    Fibrinogen-related proteins are a family of glycoproteins containing fibrinogen-like domains. Many members of these proteins play important roles in innate immune responses. We isolated a fibrinogen-related protein gene (TfFREP1) from roughskin sculpin (Trachidermus fasciatus). The TfFREP1 encoded a protein of 264 amino acids, including 231 amino acids with fibrinogen-like domains. Both quantitative real-time polymerase chain reaction and western blot analysis showed that TfFREP1 was mainly expressed in skin and gill tissues of T. fasciatus. The expression level of TfFREP1 was upregulated at both mRNA and protein levels after stimulation of lipopolysaccharide. These results suggest that TfFREP1 may be involved in T. fasciatus immune reaction.

  13. Adequate Intake levels of choline are sufficient for preventing elevations in serum markers of liver dysfunction in Mexican American men but are not optimal for minimizing plasma total homocysteine increases after a methionine load2

    PubMed Central

    Veenema, Kristin; Solis, Claudia; Li, Rui; Wang, Wei; Maletz, Charles V; Abratte, Christian M; Caudill, Marie A

    2009-01-01

    Background An adequate intake of 550 mg choline/d was established for the prevention of liver dysfunction in men, as assessed by measuring serum alanine aminotransferase concentrations. Objective This controlled feeding study investigated the influence of choline intakes ranging from 300 to 2200 mg/d on biomarkers of choline status. The effect of the methylenetetrahydrofolate reductase (MTHFR) C677T genotype on choline status was also examined. Design Mexican American men (n = 60) with different MTHFR C677T genotypes (29 677TT, 31 677CC) consumed a diet providing 300 mg choline/d plus supplemental choline intakes of 0, 250, 800, or 1900 mg/d for total choline intakes of 300, 550, 1100, or 2200 mg/d, respectively, for 12 wk; 400 μg/d as dietary folate equivalents and 173 mg betaine/d were consumed throughout the study. Results Choline intake affected the response of plasma free choline and betaine (time × choline, P < 0.001); the highest concentrations were observed in the 2200 mg/d group. Phosphatidylcholine (P = 0.026) and total cholesterol (P = 0.002) were also influenced by choline intake; diminished concentrations were observed in the 300 mg/d group. Phosphatidylcholine was modified by MTHFR genotype (P = 0.035; 677TT < 677CC). After a methionine load (100 mg/kg body wt), choline intakes of 1100 and 2200 mg/d attenuated (P = 0.016) the rise in plasma homocysteine, as did the MTHFR 677TT genotype (P < 0.001). Serum alanine aminotransferase was not influenced by the choline intakes administered in this study. Conclusions These data suggest that 550 mg choline/d is sufficient for preventing elevations in serum markers of liver dysfunction in this population under the conditions of this study; higher intakes may be needed to optimize other endpoints. PMID:18779284

  14. Turkish propolis supresses MCF-7 cell death induced by homocysteine.

    PubMed

    Tartik, Musa; Darendelioglu, Ekrem; Aykutoglu, Gurkan; Baydas, Giyasettin

    2016-08-01

    Elevated plasma homocysteine (Hcy) level is a most important risk factor for various vascular diseases including coronary, cerebral and peripheral arterial and venous thrombosis. Propolis is produced by honeybee from various oils, pollens and wax materials. Therefore, it has various biological properties including antioxidant, antitumor and antimicrobial activities. This study investigated the effects of propolis and Hcy on apoptosis in cancer cells. According to our findings, Hcy induced apoptosis in human breast adenocarcinoma (MCF-7) cells by regulating numerous genes and proteins involved in the apoptotic signal transduction pathway. In contrast, treatment with propolis inhibited caspase- 3 and -9 induced by Hcy in MCF-7 cells. It can be concluded that Hcy may augment the activity of anticancer agents that induce excessive reactive oxygen species (ROS) generation and apoptosis in their target cells. In contrast to the previous studies herein we found that propolis in low doses protected cancer cells inhibiting cellular apoptosis mediated by intracellular ROS-dependent mitochondrial pathway. PMID:27470414

  15. [Determination of homocysteine by tandem mass spectrometry with chemical ionization].

    PubMed

    Miroshnichenko, I I; Platova, A I; Safarova, T P; Iakovleva, O B

    2014-01-01

    Homocysteine (Hcy) is an intermediate of methionine metabolism. High plasma Hcy concentrations are an independent risk factor for stroke, peripheral vascular disease, deep venous thrombosis, coronary disease, and cognitive deficiency. Apparently, it is a great importance to measure Hcy levels in human blood. A new method for the quantification of Hcy by means of reversed-phase LC/atmospheric pressure chemical ionization mass spectrometry has been developed. The MRM ion transition, m/z 136.0 ® 90.0 was used for Hcy quantification. The limit of detection was 0.4 mM, quantification was performed from 1 mM to 40 mM with coefficient of determination of R2=0,997. The method was applied successfully to Hcy determination in human blood.

  16. Dysregulated Hepatic Methionine Metabolism Drives Homocysteine Elevation in Diet-Induced Nonalcoholic Fatty Liver Disease.

    PubMed

    Pacana, Tommy; Cazanave, Sophie; Verdianelli, Aurora; Patel, Vaishali; Min, Hae-Ki; Mirshahi, Faridoddin; Quinlivan, Eoin; Sanyal, Arun J

    2015-01-01

    Methionine metabolism plays a central role in methylation reactions, production of glutathione and methylarginines, and modulating homocysteine levels. The mechanisms by which these are affected in NAFLD are not fully understood. The aim is to perform a metabolomic, molecular and epigenetic analyses of hepatic methionine metabolism in diet-induced NAFLD. Female 129S1/SvlmJ;C57Bl/6J mice were fed a chow (n = 6) or high-fat high-cholesterol (HFHC) diet (n = 8) for 52 weeks. Metabolomic study, enzymatic expression and DNA methylation analyses were performed. HFHC diet led to weight gain, marked steatosis and extensive fibrosis. In the methionine cycle, hepatic methionine was depleted (30%, p< 0.01) while s-adenosylmethionine (SAM)/methionine ratio (p< 0.05), s-adenosylhomocysteine (SAH) (35%, p< 0.01) and homocysteine (25%, p< 0.01) were increased significantly. SAH hydrolase protein levels decreased significantly (p <0.01). Serine, a substrate for both homocysteine remethylation and transsulfuration, was depleted (45%, p< 0.01). In the transsulfuration pathway, cystathionine and cysteine trended upward while glutathione decreased significantly (p< 0.05). In the transmethylation pathway, levels of glycine N-methyltransferase (GNMT), the most abundant methyltransferase in the liver, decreased. The phosphatidylcholine (PC)/ phosphatidylethanolamine (PE) ratio increased significantly (p< 0.01), indicative of increased phosphatidylethanolamine methyltransferase (PEMT) activity. The protein levels of protein arginine methytransferase 1 (PRMT1) increased significantly, but its products, monomethylarginine (MMA) and asymmetric dimethylarginine (ADMA), decreased significantly. Circulating ADMA increased and approached significance (p< 0.06). Protein expression of methionine adenosyltransferase 1A, cystathionine β-synthase, γ-glutamylcysteine synthetase, betaine-homocysteine methyltransferase, and methionine synthase remained unchanged. Although gene expression of the DNA

  17. Genetic variation in homocysteine metabolism, cognition, and white matter lesions.

    PubMed

    de Lau, Lonneke M L; van Meurs, Joyce B J; Uitterlinden, André G; Smith, A David; Refsum, Helga; Johnston, Carole; Breteler, Monique M B

    2010-11-01

    Several studies have shown an association between homocysteine concentration and cognitive performance or cerebral white matter lesions. However, variations in genes encoding for enzymes and other proteins that play a role in homocysteine metabolism have hardly been evaluated in relation to these outcome measures. In the population-based Rotterdam Scan Study, we examined the association of seven polymorphisms of genes involved in homocysteine metabolism (MTHFR 677C>T, MTHFR 1298A>C, RFC 80G>A, TC 776C>G, MTR 2756A>G, MTRR 66A>G, and CBS 844ins68) with plasma total homocysteine, cognitive performance, and cerebral white matter lesions among 1011 non-demented elderly participants. Of all the studied polymorphisms, only MTHFR 677C>T was associated with homocysteine concentration. No significant relationship was observed for any of the polymorphisms with cognitive performance or severity of cerebral white matter lesions.

  18. Effects of oral contraceptives, or lanosterol, on ADP-induced aggregation and binding of /sup 125/I-fibrinogen to rat platelets

    SciTech Connect

    McGregor, L.; Toor, B.; McGregor, J.L.; Renaud, S.; Clemetson, K.J.

    1984-03-01

    The aggregation to ADP and the binding of /sup 125/I-fibrinogen to platelets from rats treated with oral contraceptives or normal platelets treated in vitro with lanosterol were compared to their respective controls. Both types of platelets showed a significant increase in ADP-induced aggregation and in binding of fibrinogen, indicating that the effect of oral contraceptives could be partly due to increased levels of lanosterol in platelet membrane.

  19. Specific potassium ion interactions facilitate homocysteine binding to betaine-homocysteine S-methyltransferase.

    PubMed

    Mládková, Jana; Hladílková, Jana; Diamond, Carrie E; Tryon, Katherine; Yamada, Kazuhiro; Garrow, Timothy A; Jungwirth, Pavel; Koutmos, Markos; Jiráček, Jiří

    2014-10-01

    Betaine-homocysteine S-methyltransferase (BHMT) is a zinc-dependent methyltransferase that uses betaine as the methyl donor for the remethylation of homocysteine to form methionine. This reaction supports S-adenosylmethionine biosynthesis, which is required for hundreds of methylation reactions in humans. Herein we report that BHMT is activated by potassium ions with an apparent K(M) for K⁺ of about 100 µM. The presence of potassium ions lowers the apparent K(M) of the enzyme for homocysteine, but it does not affect the apparent K(M) for betaine or the apparent k(cat) for either substrate. We employed molecular dynamics (MD) simulations to theoretically predict and protein crystallography to experimentally localize the binding site(s) for potassium ion(s). Simulations predicted that K⁺ ion would interact with residues Asp26 and/or Glu159. Our crystal structure of BHMT bound to homocysteine confirms these sites of interaction and reveals further contacts between K⁺ ion and BHMT residues Gly27, Gln72, Gln247, and Gly298. The potassium binding residues in BHMT partially overlap with the previously identified DGG (Asp26-Gly27-Gly28) fingerprint in the Pfam 02574 group of methyltransferases. Subsequent biochemical characterization of several site-specific BHMT mutants confirmed the results obtained by the MD simulations and crystallographic data. Together, the data herein indicate that the role of potassium ions in BHMT is structural and that potassium ion facilitates the specific binding of homocysteine to the active site of the enzyme.

  20. Association of CD2 with fibrinogen in human plasma: depletion of the soluble E-receptor in blood clotting.

    PubMed

    Smorodin, Eugeniy P; Kurtenkov, O A; Shevchuk, I N

    2007-01-01

    The soluble E-receptor (SER) of lymphocytes that is related to CD2 was detected in human plasma and serum using immunoelectrophoresis with sheep antiserum. All plasma samples (n=18) demonstrated reactivity with antiserum, whereas the reactivity of the corresponding sera remained low or undetectable. The depletion of SER in clotting is associated with fibrinogen, as shown by crossed-affinity immunoelectrophoresis with antisera to plasma proteins. The SER-associated fibrinogen was purified and analysed by the SDS-polyacrylamide gel electrophoresis and immunoblotting. A band close to 66 kDa was detected with monoclonal antibodies to CD2. The association of CD2 and other soluble receptors with fibrinogen via domains is suggested. It is recommended that the fresh plasma, not serum, should be used to study circulating receptors because coagulation may appreciably diminish their physiological level in blood samples.

  1. /sup 111/In-platelet and /sup 125/I-fibrinogen deposition in the lungs in experimental acute pancreatitis

    SciTech Connect

    Goulbourne, I.A.; Watson, H.; Davies, G.C.

    1987-12-01

    An experimental model of acute pancreatitis in rats has been used to study intrapulmonary /sup 125/I-fibrinogen and /sup 111/In-platelet deposition. Pancreatitis caused a significant increase in wet lung weight compared to normal, and this could be abolished by heparin or aspirin pretreatment. /sup 125/I-fibrinogen was deposited in the lungs of animals to a significantly greater degree than in controls (P less than 0.01). /sup 125/I-fibrinogen deposition was reduced to control levels by pretreatment with aspirin or heparin (P less than 0.05). The uptake of radiolabeled platelets was greater in pancreatitis than in controls (P less than 0.001). Pancreatitis appears to be responsible for platelet entrapment in the lungs. Platelet uptake was reduced by heparin treatment but unaffected by aspirin therapy.

  2. Human fibrinogen adsorption on positively charged latex particles.

    PubMed

    Zeliszewska, Paulina; Bratek-Skicki, Anna; Adamczyk, Zbigniew; Cieśla, Michał

    2014-09-23

    Fibrinogen (Fb) adsorption on positively charged latex particles (average diameter of 800 nm) was studied using the microelectrophoretic and the concentration depletion methods based on AFM imaging. Monolayers on latex were adsorbed from diluted bulk solutions at pH 7.4 and an ionic strength in the range of 10(-3) to 0.15 M where fibrinogen molecules exhibited an average negative charge. The electrophoretic mobility of the latex after controlled fibrinogen adsorption was systematically measured. A monotonic decrease in the electrophoretic mobility of fibrinogen-covered latex was observed for all ionic strengths. The results of these experiments were interpreted according to the three-dimensional electrokinetic model. It was also determined using the concentration depletion method that fibrinogen adsorption was irreversible and the maximum coverage was equal to 0.6 mg m(-2) for ionic strength 10(-3) M and 1.3 mg m(-2) for ionic strength 0.15 M. The increase of the maximum coverage was confirmed by theoretical modeling based on the random sequential adsorption approach. Paradoxically, the maximum coverage of fibrinogen on positively charged latex particles was more than two times lower than the maximum coverage obtained for negative latex particles (3.2 mg m(-2)) at pH 7.4 and ionic strength of 0.15 M. This was interpreted as a result of the side-on adsorption of fibrinogen molecules with their negatively charged core attached to the positively charged latex surface. The stability and acid base properties of fibrinogen monolayers on latex were also determined in pH cycling experiments where it was observed that there were no irreversible conformational changes in the fibrinogen monolayers. Additionally, the zeta potential of monolayers was more positive than the zeta potential of fibrinogen in the bulk, which proves a heterogeneous charge distribution. These experimental data reveal a new, side-on adsorption mechanism of fibrinogen on positively charged surfaces and

  3. Effects of pyridoxine on growth performance and plasma aminotransferases and homocysteine of white pekin ducks.

    PubMed

    Xie, Ming; Tang, Jing; Wen, Zhiguo; Huang, Wei; Hou, Shuisheng

    2014-12-01

    A dose-response experiment with seven supplemental pyridoxine levels (0, 0.66, 1.32, 1.98, 2.64, 3.30, and 3.96 mg/kg) was conducted to investigate the effects of pyridoxine on growth performance and plasma aminotransferases and homocysteine of White Pekin ducks and to estimate pyridoxine requirement for these birds. A total of 336 one-day-old male White Pekin ducks were divided to 7 experimental treatments and each treatment contained 8 replicate pens with 6 birds per pen. Ducks were reared in raised wire-floor pens from hatch to 28 d of age. At 28 d of age, the weight gain, feed intake, feed/gain, and the aspartate aminotransferase, alanine aminotransferase, and homocysteine in plasma of ducks from each pen were all measured. In our study, the pyridoxine deficiency of ducks was characterized by growth depression, decreasing plasma aspartate aminotransferase activity and increasing plasma homocysteine. The ducks fed vitamin B6-deficient basal diets had the worst weight gain and feed/gain among all birds and this growth depression was alleviated (p<0.05) when pyridoxine was supplemented to basal diets. On the other hand, plasma aspartate aminotransferase and homocysteine may be the sensitive indicators for vitamin B6 status of ducks. The ducks fed basal diets had much lower aspartate aminotransferase activity and higher homocysteine level in plasma compared with other birds fed pyridoxine-supplemented diets (p<0.05). According to quadratic regression, the supplemental pyridoxine requirements of Pekin ducks from hatch to 28 days of age was 2.44 mg/kg for feed/gain and 2.08 mg/kg for plasma aspartate aminotransferase and the corresponding total requirements of this vitamin for these two criteria were 4.37 and 4.01 mg/kg when the pyridoxine concentration of basal diets was included, respectively. All data suggested that pyridoxine deficiency could cause growth retardation in ducks and the deficiency of this vitamin could be indicated by decreasing plasma aspartate

  4. Impact of homocysteine-thiolactone on plasma fibrin networks.

    PubMed

    Genoud, Valeria; Lauricella, Ana María; Kordich, Lucía C; Quintana, Irene

    2014-11-01

    Epidemiologic studies have shown that hyperhomocysteinemia is an independent risk factor for vascular disease. Homocysteine (Hcy) circulates as different species, mostly protein bound, and approximately 1% as its reduced form and the cyclic thioester homocysteine-thiolactone (HTL). Despite the level of plasma thiolactone being markedly low, detrimental effects are related to its high reactivity. HTL reacts with proteins by acylation of free basic amino groups; in particular, the epsilon-amino group of lysine residues forms adducts and induces structural and functional changes in plasma proteins. In order to assess the effects of HTL on plasma fibrin networks, a pool of normal plasma incubated with HTL (100, 500 and 1,000 μmol/L, respectively) was evaluated by global coagulation tests and fibrin formation kinetic assays, and the resulting fibrin was observed by scanning electron microscopy. HTL significantly prolonged global coagulation tests in a concentration-dependent manner with respect to control, and increases were up to 14.5%. Fibrin formation kinetic parameters displayed statistically significant differences between HTL-treated plasma and control in a concentration-dependent way, showing higher lag phase and lower maximum reaction velocity and final network optical density. Electron microscopy analysis of HTL plasma networks revealed a compact architecture, with more branches and shorter fibers than control. We can conclude that HTL induced a slower coagulation process, rendering more tightly packed fibrin clots. Since these features of the networks have been related to impaired fibrinolysis, the N-homocysteinylation reactions would be involved in the prothrombotic effects associated to hyperhomocysteinemia.

  5. Homocysteine and Raynaud's phenomenon: a review.

    PubMed

    Lazzerini, Pietro Enea; Capecchi, Pier Leopoldo; Bisogno, Stefania; Cozzalupi, Mauro; Rossi, Pier Carlo; Pasini, Franco Laghi

    2010-01-01

    Raynaud's phenomenon, categorized as primary and secondary when occurring isolated or in association with an underlying disease, respectively, is a paroxysmal and recurrent acral ischemia resulting from an abnormal arterial vasospastic response to cold or emotional stress. The key issue in the pathogenesis of Raynaud's phenomenon is presumed to be a dysregulation in the mechanisms of vascular motility resulting in an imbalance between vasodilatation and vasoconstriction. Homocysteine, a non-protein forming sulphured amino acid proposed as an independent risk factor for atherothrombosis in the general population, clearly demonstrated to produce vascular damage through mechanisms also including endothelial injury and modifications in circulating mediators of vasomotion. The rationale for homocysteine involvement in the pathogenesis of Raynaud's phenomenon led some authors to investigate the possible association between mild hyperhomocysteinemia and such a vascular disturbance, particularly in the course of connective tissue disease. Here we review data regarding this putative association and the supposed mechanisms involved, also discussing the emblematic case of a patient with new-onset severe Raynaud's phenomenon and markedly elevated homocysteinemia.

  6. Distinct Adsorption Configurations and Self-Assembly Characteristics of Fibrinogen on Chemically Uniform and Alternating Surfaces including Block Copolymer Nanodomains

    PubMed Central

    2015-01-01

    Understanding protein–surface interactions is crucial to solid-state biomedical applications whose functionality is directly correlated with the precise control of the adsorption configuration, surface packing, loading density, and bioactivity of protein molecules. Because of the small dimensions and highly amphiphilic nature of proteins, investigation of protein adsorption performed on nanoscale topology can shed light on subprotein-level interaction preferences. In this study, we examine the adsorption and assembly behavior of a highly elongated protein, fibrinogen, on both chemically uniform (as-is and buffered HF-treated SiO2/Si, and homopolymers of polystyrene and poly(methyl methacrylate)) and varying (polystyrene-block-poly(methyl methacrylate)) surfaces. By focusing on high-resolution imaging of individual protein molecules whose configurations are influenced by protein–surface rather than protein–protein interactions, fibrinogen conformations characteristic to each surface are identified and statistically analyzed for structural similarities/differences in key protein domains. By exploiting block copolymer nanodomains whose repeat distance is commensurate with the length of the individual protein, we determine that fibrinogen exhibits a more neutral tendency for interaction with both polystyrene and poly(methyl methacrylate) blocks relative to the case of common globular proteins. Factors affecting fibrinogen–polymer interactions are discussed in terms of hydrophobic and electrostatic interactions. In addition, assembly and packing attributes of fibrinogen are determined at different loading conditions. Primary orientations of fibrinogen and its rearrangements with respect to the underlying diblock nanodomains associated with different surface coverage are explained by pertinent protein interaction mechanisms. On the basis of two-dimensional stacking behavior, a protein assembly model is proposed for the formation of an extended fibrinogen network

  7. Status of B-vitamins and homocysteine in diabetic retinopathy: association with vitamin-B12 deficiency and hyperhomocysteinemia.

    PubMed

    Satyanarayana, Alleboena; Balakrishna, Nagalla; Pitla, Sujatha; Reddy, Paduru Yadagiri; Mudili, Sivaprasad; Lopamudra, Pratti; Suryanarayana, Palla; Viswanath, Kalluru; Ayyagari, Radha; Reddy, Geereddy Bhanuprakash

    2011-01-01

    Diabetic retinopathy (DR) is a common cause of blindness. Although many studies have indicated an association between homocysteine and DR, the results so far have been equivocal. Amongst the many determinants of homocysteine, B-vitamin status was shown to be a major confounding factor, yet very little is known about its relationship to DR. In the present study, we, therefore, investigated the status of B-vitamins and homocysteine in DR. A cross-sectional case-control study was conducted with 100 normal control (CN) subjects and 300 subjects with type-2 diabetes (T2D). Of the 300 subjects with T2D, 200 had retinopathy (DR) and 100 did not (DNR). After a complete ophthalmic examination including fundus fluorescein angiography, the clinical profile and the blood levels of all B-vitamins and homocysteine were analyzed. While mean plasma homocysteine levels were found to be higher in T2D patients compared with CN subjects, homocysteine levels were particularly high in the DR group. There were no group differences in the blood levels of vitamins B1 and B2. Although the plasma vitamin-B6 and folic acid levels were significantly lower in the DNR and DR groups compared with the CN group, there were no significant differences between the diabetes groups. Interestingly, plasma vitamin-B12 levels were found to be significantly lower in the diabetes groups compared with the CN group; further, the levels were significantly lower in the DR group compared with the DNR group. Higher homocysteine levels were significantly associated with lower vitamin-B12 and folic acid but not with other B-vitamins. Additionally, hyperhomocysteinemia and vitamin-B12 deficiency did not seem to be related to subjects' age, body mass index, or duration of diabetes. These results thus suggest a possible association between vitamin-B12 deficiency and hyperhomocysteinemia in DR. Further, the data indicate that vitamin-B12 deficiency could be an independent risk factor for DR.

  8. A Mendelian Randomization Study of Plasma Homocysteine and Multiple Myeloma

    PubMed Central

    Xuan, Yang; Li, Xiao-Hong; Hu, Zhong-Qian; Teng, Zhi-Mei; Hu, Dao-Jun

    2016-01-01

    Observational studies have demonstrated an association between elevated homocysteine (Hcy) level and risk of multiple myeloma (MM). However, it remains unclear whether this relationship is causal. We conducted a Mendelian randomization (MR) study to evaluate whether genetically increased Hcy level influences the risk of MM. We used the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism as an instrumental variable, which affects the plasma Hcy levels. Estimate of its effect on plasma Hcy level was based on a recent genome-wide meta-analysis of 44,147 individuals, while estimate of its effect on MM risk was obtained through meta-analysis of case-control studies with 2,092 cases and 4,954 controls. By combining these two estimates, we found that per one standard-deviation (SD) increase in natural log-transformed plasma Hcy levels conferred a 2.67-fold increase in risk for MM (95% confidence interval (CI): 1.12–6.38; P = 2.7 × 10−2). Our study suggests that elevated Hcy levels are causally associated with an increased risk of developing MM. Whether Hcy-lowering therapy can prevent MM merits further investigation in long-term randomized controlled trials (RCTs). PMID:27126524

  9. Homocysteine homeostasis in the rat is maintained by compensatory changes in cystathionine β-synthase, betaine-homocysteine methyltransferase, and phosphatidylethanolamine N-methyltransferase gene transcription occurring in response to maternal protein and folic acid intake during pregnancy and fat intake after weaning.

    PubMed

    Chmurzynska, Agata; Malinowska, Anna M

    2011-07-01

    The reactions of the methionine/homocysteine pathway are mediated by several enzymes, including phosphatidylethanolamine N-methyltransferase, cystathionine β-synthase, and betaine-homocysteine methyltransferase. Homocysteine homeostasis is regulated by these enzymes. We hypothesized here that the protein and folic acid content in the maternal diet affects methionine/homocysteine metabolism in the progeny. To test this hypothesis, pregnant rats were fed a diet with normal protein and normal folic acid levels (a modified casein-based AIN-93G diet), a protein-restricted and normal folic acid diet, a protein-restricted and folic acid-supplemented diet, or a normal protein and folic acid-supplemented diet. The progeny were fed either the modified AIN-93G diet or a high-fat lard-based diet. Progeny were analyzed for expression of the phosphatidylethanolamine N-methyltransferase, cystathionine β-synthase, and betaine-homocysteine methyltransferase genes in the liver and for serum homocysteine concentration. Interactions between prenatal and postnatal nutrition were also determined. The progeny of the dams fed the diets supplemented with folic acid showed decreased expression of all 3 genes (P < .001). An interaction effect between the protein and folic acid content in the maternal diet contributed to this down-regulation (P < .001), and the postweaning diet modified these effects. Serum homocysteine concentrations were approximately 15% higher in the male rats (P < .01), but neither prenatal nutrition nor the postweaning diet affected it significantly. We conclude that maternal diet during gestation has an important effect on the transcription level of these 3 genes, but changes in gene expression were not associated with significant changes in progeny homocysteine concentrations.

  10. Serum folate, homocysteine and colorectal cancer risk in women: a nested case–control study

    PubMed Central

    Kato, I; Dnistrian, A M; Schwartz, M; Toniolo, P; Koenig, K; Shore, R E; Akhmedkhanov, A; Zeleniuch-Jacquotte, A; Riboli, E

    1999-01-01

    Accumulating evidence suggests that folate, which is plentiful in vegetables and fruits, may be protective against colorectal cancer. The authors have studied the relationship of baseline levels of serum folate and homocysteine to the subsequent risk of colorectal cancer in a nested case–control study including 105 cases and 523 matched controls from the New York University Women's Health Study cohort. In univariate analyses, the cases had lower serum folate and higher serum homocysteine levels than controls. The difference was more significant for folate (P < 0.001) than for homocysteine (P = 0.04). After ad'justing for potential confounders, the risk of colorectal cancer in the subjects in the highest quartile of serum folate was half that of those in the lowest quartile (odds ratio, OR = 0.52, 95% confidence interval, CI = 0.27–0.97, P-value for trend = 0.04). The OR for the highest quartile of homocysteine, relative to the lowest quartile, was 1.72 (95% CI = 0.83–3.65, P-value for trend = 0.09). In addition, the risk of colorectal cancer was almost twice as high in subjects with below-median serum folate and above-median total alcohol intake compared with those with above-median serum folate and below-median alcohol consumption (OR = 1.99, 95% CI = 0.92–4.29). The potentially protective effects of folate need to be confirmed in clinical trials. © 1999 Cancer Research Campaign PMID:10206314

  11. Molecular characterization of 7 patients affected by dys- or hypo-dysfibrinogenemia: Identification of a novel mutation in the fibrinogen Bbeta chain causing a gain of glycosylation.

    PubMed

    Asselta, Rosanna; Robusto, Michela; Platé, Manuela; Santoro, Cristina; Peyvandi, Flora; Duga, Stefano

    2015-07-01

    Fibrinogen is a hexameric glycoprotein consisting of two sets of three polypeptides (the Aα, Bβ, and γ chains, encoded by the three genes FGA, FGB, and FGG). It is involved in the final phase of the coagulation process, being the precursor of the fibrin monomers necessary for the formation of the hemostatic plug. Rare inherited fibrinogen disorders can manifest as quantitative deficiencies, qualitative defects, or both. In particular, dysfibrinogenemia and hypo-dysfibrinogenemia are characterized by reduced functional activity associated with normal or reduced antigen levels, and are usually determined by heterozygous mutations affecting any of the three fibrinogen genes. In this study, we investigated the genetic basis of dys- and hypo-dysfibrinogenemia in seven unrelated patients. Mutational screening disclosed six different variants, two of which novel (FGB-p.Asp185Asn and FGG-p.Asn230Lys). The molecular characterization of the FGG-p.Asn230Lys mutation, performed by transient expression experiments of the recombinant mutant protein, demonstrated that it induces an almost complete impairment in fibrinogen secretion, according to a molecular mechanism often associated with quantitative fibrinogen disorders. Conversely, the FGB-p.Asp185Asn variant was demonstrated to be a gain-of-glycosylation mutation leading to a hyperglycosylation of the Bβ chain, not affecting fibrinogen assembly and secretion. To our knowledge, this is the second gain-of-glycosylation mutation involving the FGB gene.

  12. [Fibrinogen/LDL apheresis for treatment of sudden hearing loss: an observational study on 152 patients].

    PubMed

    Canis, M; Heigl, F; Hettich, R; Osterkorn, D; Osterkorn, K; Suckfuell, M

    2008-09-01

    Disturbances of cochlear microcirculation are among the most discussed causes of sudden sensorineural hearing loss. Increased levels of cholesterol and fibrinogen seem to act as risk factors for inner ear disorders. Fibrinogen/LDL apheresis greatly reduces the concentration of plasma fibrinogen thus leading to improved cochlear blood flow. In a retrospective case series remission rates of 152 patients suffering from sudden sensorineural hearing loss and resistant to former treatment were investigated after treatment with a single apheresis. Complete remission was reported in 11% of patients, partial remission in 43%. 37% had no change of hearing threshold and 2% reported a decrease in hearing. Rates of complete remissions decreased from 22% within the first 2 weeks after onset of hearing loss to 14% after 6 weeks. In the same period of time rates of partial remissions decreased from 33% to 13%. The present study shows that apheresis achieved complete or partial remission in 54% of patients even after unsuccessful treatment with another therapy and the therapeutic window lies by approximately 6 weeks.

  13. Randomised clinical trial of an intensive intervention in the primary care setting of patients with high plasma fibrinogen in the primary prevention of cardiovascular disease

    PubMed Central

    2012-01-01

    Background We have studied the possible effects of an intensive lifestyle change program on plasma fibrinogen levels, in patients with no cardiovascular disease, with elevated levels of fibrinogen, normal cholesterol levels, and a moderate estimated risk of coronary heart disease (CHD) and we have also analysed whether the effect on fibrinogen is independent of the effect on lipids. Results This clinical trial was controlled, unblinded and randomized, with parallel groups, done in 13 Basic Health Areas (BHA) in l'Hospitalet de Llobregat (Barcelona) and Barcelona city. The study included 436 patients, aged between 35 and 75 years, with no cardiovascular disease, elevated levels of fibrinogen (> 300 mg/dl), cholesterol < 250 mg/dl, 218 of whom received a more intensive intervention consisting of advice on lifestyle and treatment. The follow-up frequency of the intervention group was every 2 months. The other 218 patients followed their standard care in the BHAs. Fibrinogen, plasma cholesterol and other clinical biochemistry parameters were assessed. The evaluation of the baseline characteristics of the patients showed that both groups were homogenous. Obesity and hypertension were the most prevalent risk factors. After 24 months of the study, statistically significant changes were seen between the adjusted means of the two groups, for the following parameters: fibrinogen, plasma cholesterol, systolic and diastolic blood pressure and body mass index. Conclusion Intensive intervention to achieve lifestyle changes has shown to be effective in reducing some of the estimated CHD factors. However, the effect of intensive intervention on plasma fibrinogen levels did not correlate with the variations in cholesterol. Trial Registration ClinicalTrials.gov: NCT01089530 PMID:22381072

  14. Homocysteine injures vascular endothelial cells by inhibiting mitochondrial activity

    PubMed Central

    Yang, Fengyong; Qi, Xiujing; Gao, Zheng; Yang, Xingju; Zheng, Xingfeng; Duan, Chonghao; Zheng, Jian

    2016-01-01

    The aim of the present study was to investigate the role of homocysteine (Hcy) in the pathogenesis of pulmonary embolism (PE) and the associated molecular mechanisms in human umbilical vein endothelial cells (HUVECs). Hcy contents were detected with high-performance liquid chromatography. Apoptosis was detected by flow cytometry using Annexin-V staining. Cytochrome c oxidase (COX) activity was assessed with an enzyme activity assay, and the expression levels of COX 17 were determined by western blot analysis. Intracellular reactive oxygen species levels were measured using a microplate reader with a fluorescence probe. The results demonstrated that, compared with the control group, the serum Hcy levels were significantly elevated in the PE group, suggesting that Hcy may be an indicator for PE. Following treatment with Hcy, the apoptosis rate was markedly elevated in HUVECs. Moreover, Hcy decreased COX activity and downregulated the expression of COX 17 in HUVECs. Furthermore, Hcy increased the ROS levels in these endothelial cells. However, all the above-mentioned physiopathological changes induced by Hcy in HUVECs could be restored by folic acid. In conclusion, the results of the present study demonstrated that Hcy inhibited COX activity, downregulated COX 17 expression, increased intracellular ROS levels and enhanced apoptosis in endothelial cells.

  15. Fibrinogen Yecheon: congenital dysfibrinogenemia with gamma methionine-310 to threonine substitution.

    PubMed

    Park, Eunkyung; Park, Geumbore; Park, Rojin; Kim, Hee-Jin; Lee, Sang Jae; Cha, Young Joo

    2009-12-01

    This case study reports a rare fibrinogen variant, gamma Met310Thr mutation, for the first time in Korea. The case shows a point mutation from T to C in the 1,007th nucleotide of the FGG gene. This report describes a variant fibrinogen, hereinafter called "fibrinogen Yecheon", using the name after the town where the patient was living at the time of diagnosis. Fibrinogen Yecheon has a de novo heterozygous point mutation of FGG resulting in gamma Met310Thr and subsequent extra N-glycosylation at gamma Asn308. Extra N-glycosylated fibrinogen is considered a main inhibitor of normal fibrinogen activity.

  16. Effects of folic acid and vitamin B12 supplements on folate and homocysteine metabolism in pigs during early pregnancy.

    PubMed

    Guay, Frédéric; Jacques Matte, J; Girard, Christiane L; Palin, Marie-France; Giguère, Alain; Laforest, Jean-Paul

    2002-09-01

    The present experiment aimed to determine the effects of supplements of folic acid (FA) alone or in combination with vitamin B12 on folate and homocysteine metabolism in gestating nulliparous Yorkshire-Landrace (YL) and multiparous Landrace (LD) occidental sows and multiparous Chinese Meishan-Landrace (ML) sows. LD sows were randomly assigned to two treatments: 0 or 15 mg FA/kg diet while YL and ML sows were assigned to three treatments: 0 mg FA/kg diet, 15 mg FA/kg or 15 mg vitamin B12/kg diet. Supplements were given from the oestrus preceding insemination up to slaughter on day 15 of gestation. At slaughter, a uterine flush was collected to determine uterine contents of homocysteine, methionine, tetrahydrofolate (THF), 5-methyl-THF, pyridoxal 5-phosphate (P5P) and vitamin B12. Blood samples were taken at first oestrus, at insemination and on days 5, 10 and 15 of gestation to determine plasma concentrations of homocysteine, methionine, THF, 5-methyl-THF, P5P, vitamin B12 and relative total folate-binding capacity. In occidental sows (YL and LD), the FA supplement tended to decrease uterine flush content of homocysteine (P=0.06) and concentrations of plasma homocysteine (P=0.09). Nulliparous YL sows had lower concentrations of plasma homocysteine, methionine, THF and 5-methyl-THF (P<0.05) than multiparous LD sows. Multiparous ML and LD sows had similar concentrations of plasma THF, 5-methyl-THF, methionine and vitamin B12, but ML sows had lower concentrations of plasma homocysteine (P<0.05). The vitamin B12 supplement increased concentrations of plasma vitamin B12 (P<0.05) both in multiparous ML and nulliparous YL sows, but had no effect on the composition of either uterine flush or plasma. The present results showed also that sows had a low vitamin B12 status (<200 pg/ml) and high circulating homocysteine levels (>15 microm) during the first 15 d of gestation. Furthermore, the vitamin B12 content in uterine secretions represented between 180 and 300 % of the total

  17. Organotypic tissue culture investigation of homocysteine thiolactone cardiotoxic effect.

    PubMed

    Lopatina, Ekaterina V; Kipenko, A V; Penniyaynen, V A; Pasatetskaya, N A; Djuric, D; Krylov, B V

    2015-06-01

    Homocysteine thiolactone was demonstrated to inhibit the growth of 10-12-day-old chicken embryo cardiac tissue explants at 7 × 10⁻⁹ -1 × 10⁻³ M concentrations in a dose-dependent manner. The maximal cardiotoxic effect of homocysteine thiolactone was detected at 1 × 10⁻³ M, which corresponds to severe hyperhomocysteinemia. The results of experiments on culturing of cardiac tissue explants in the medium containing homocysteine thiolactone (1 × 10⁻³ M) and ouabain at concentrations regulating the signal-transducing (1 × 10⁻¹⁰ M) and pumping (1 × 10⁻⁸ M) functions of Na⁺,K⁺ -ATPase indicate that the cardiotoxic effect of homocysteine thiolactone is supposed to result from inhibition of the Na⁺,K⁺ -ATPase pumping function.

  18. Fibrin(ogen) mediates acute inflammatory responses to biomaterials

    PubMed Central

    1993-01-01

    Although "biocompatible" polymeric elastomers are generally nontoxic, nonimmunogenic, and chemically inert, implants made of these materials may trigger acute and chronic inflammatory responses. Early interactions between implants and inflammatory cells are probably mediated by a layer of host proteins on the material surface. To evaluate the importance of this protein layer, we studied acute inflammatory responses of mice to samples of polyester terephthalate film (PET) that were implanted intraperitoneally for short periods. Material preincubated with albumin is "passivated," accumulating very few adherent neutrophils or macrophages, whereas uncoated or plasma- coated PET attracts large numbers of phagocytes. Neither IgG adsorption nor surface complement activation is necessary for this acute inflammation; phagocyte accumulation on uncoated implants is normal in hypogammaglobulinemic mice and in severely hypocomplementemic mice. Rather, spontaneous adsorption of fibrinogen appears to be critical: (a) PET coated with serum or hypofibrinogenemic plasma attracts as few phagocytes as does albumin-coated material; (b) in contrast, PET preincubated with serum or hypofibrinogenemic plasma containing physiologic amounts of fibrinogen elicits "normal" phagocyte recruitment; (c) most importantly, hypofibrinogenemic mice do not mount an inflammatory response to implanted PET unless the material is coated with fibrinogen or the animals are injected with fibrinogen before implantation. Thus, spontaneous adsorption of fibrinogen appears to initiate the acute inflammatory response to an implanted polymer, suggesting an interesting nexus between two major iatrogenic effects of biomaterials: clotting and inflammation. PMID:8245787

  19. Aronia melanocarpa as a protector against nitration of fibrinogen.

    PubMed

    Bijak, Michał; Saluk, Joanna; Antosik, Adam; Ponczek, Michał B; Żbikowska, Halina M; Borowiecka, Marta; Nowak, Paweł

    2013-04-01

    Fibrinogen (Fg) also known as coagulation factor I represents about 4% of the total human plasma proteins. The main function of Fg is its involvement in last phase of blood coagulation cascade, when thrombin-induced conversion of dissolved plasma fibrinogen into an insoluble fibrin clot occurs. The reaction of fibrinogen with peroxynitrite causes both structural modifications and changes of the biological properties of this plasma glycoprotein. Recently, there is an increased interest in the screening of natural products present in fruits, vegetables and herbs for their possible antioxidative activities. Therefore, the aim of our study was to estimate the effect of extract from berries of Aronia melanocarpa against nitrative and oxidative damage induced by peroxynitrite. The extract from A. melanocarpa (0.5-50 μg/ml) added to Fg 10 min before peroxynitrite (100 μM) significantly inhibited both the formation of the high molecular weight protein aggregates and nitration of Fg molecule. The extract also abolished peroxynitrite-induced inhibition of fibrinogen polymerization (by 95% at 50 μg/ml). The obtained results indicate that natural extract from berries of A. melanocarpa has protective effects against peroxynitrite-induced nitrative damage of plasma fibrinogen, and therefore may contribute in the prevention of peroxynitrite-related cardiovascular or inflammatory diseases.

  20. B vitamins and homocysteine in cardiovascular disease and aging.

    PubMed

    Wilcken, D E; Wilcken, B

    1998-11-20

    The sulfur-containing amino acid, homocysteine, is formed from the essential amino acid methionine, and a number of B vitamins are involved in methionine metabolism. Pyridoxine, vitamin B6, is a cofactor for cystathionine beta synthase, which mediates the transformation of homocysteine to cystathionine, the initial step in the transsulfuration pathway and the urinary excretion of sulfur. In a normal diet there is conservation of the carbon skeleton, and about 50% of the homocysteine formed is remethylated to methionine via steps that require folic acid and vitamin B12. A deficiency of any of these three vitamins leads to modest homocyst(e)ine elevation, as does diminished renal function, both of which are common in the elderly. It is also established that homocyst(e)ine elevation of this order is associated with increased cardiovascular risk but is also associated with most established risk factors, although it is thought to be an independent contributor. In the inborn error of metabolism homocystinuria due to cystathionine beta synthase deficiency there is greatly increased circulating homocyst(e)ine and a clear association with precocious vascular disease. In about 50% of these patients there is a vascular event before the age of 30 years. The homocysteine-induced adverse vascular changes appear to result from endothelial and smooth muscle cell effects and increased thrombogenesis. We have documented a highly significant reduction in the occurrence of vascular events during 539 patient years of treatment in 32 patients with cystathionine beta synthase deficiency (mean age 30 years, range 9-66 years) by aggressive homocyst(e)ine lowering with pyridoxine, folic acid, and B12 (p = 0.0001). The 15 pyridoxine nonresponsive patients also received oral betaine. Although a cause and effect relationship is postulated for the increased cardiovascular risk associated with mild homocysteine elevation, a common cause of this elevation is the methylenetetrahydrofolate

  1. Insulin counter-regulatory factors, fibrinogen and C-reactive protein during olanzapine administration: effects of the antidiabetic metformin.

    PubMed

    Baptista, Trino; Sandia, Ignacio; Lacruz, Anny; Rangel, Nairy; de Mendoza, Soaira; Beaulieu, Serge; Contreras, Quilianio; Galeazzi, Tatiana; Vargas, Doritza

    2007-03-01

    In this study, the Authors assessed some insulin counter-regulatory factors, fibrinogen and C-reactive protein after olanzapine administration, and the effect of metformin on these variables, 37 patients with chronic schizophrenia were given olanzapine (10 mg/day for 14 weeks). Nineteen patients received metformin (850-2550 mg/day) and 18 received placebo in a randomized, double-blind protocol. The following variables were quantified before and after olanzapine: cortisol, leptin, tumor necrosis factor-alpha, glucagon, growth hormone, fibrinogen and C-reactive protein. Results were correlated with the changes in body weight and the insulin resistance index. We have reported elsewhere that metformin did not prevent olanzapine-induced weight gain, and the insulin resistance index significantly decreased after metformin and placebo; Baptista T, et al. Can J Psychiatry 2006; 51: 192-196. Cortisol, tumor necrosis factor-alpha and fibrinogen levels significantly decreased in both groups. Glucagon significantly increased after metformin (P=0.03). Leptin tended to increase after placebo (P=0.1) and displayed a small nonsignificant reduction after metformin. The C-reactive protein did not change significantly in any group. Contrarily to most published studies, olanzapine was associated with decreased insulin resistance. Decrements in cortisol, fibrinogen and tumor necrosis factor-alpha levels point to an improvement in the metabolic profile. The trend for leptin to increase after placebo, but not after metformin in spite of similar weight gain suggests a beneficial effect of this antidiabetic agent. PMID:17293706

  2. Biochemical and molecular characterization of the homocysteine S-methyltransferase from broccoli (Brassica oleracea var. italica).

    PubMed

    Lyi, Sangbom M; Zhou, Xin; Kochian, Leon V; Li, Li

    2007-04-01

    Plants are known for their unique ability to synthesize methionine from S-methylmethionine (SMM) and homocysteine using the enzyme SMM: homocysteine S-methyltransferase (HMT) in the SMM cycle. Two cDNAs exhibiting HMT activity were cloned from broccoli and functionally expressed in E. coli. One cDNA, that encodes an enzyme with high substrate specificity for homocysteine, was designated as BoHMT1. The other cDNA was the BoSMT gene that we previously characterized and encodes a selenocysteine methyltransferase (Lyi, S.M., Heller, L.I., Rutzke, M., Welch, R.M., Kochian, L.V., Li, L., 2005. Molecular and biochemical characterization of the selenocysteine Se-methyltransferase gene and Se-methylselenocysteine synthesis in broccoli. Plant Physiol. 138, 409-420). Both exist as single gene sequences in the broccoli genome. While BoSMT expression was extremely low or undetectable in broccoli plants unless the plants were exposed to selenium, the BoHMT1 mRNA accumulated in most tissues of the plant except older leaves. In contrast to BoSMT whose expression was dramatically upregulated by treating plants with selenate, the transcript levels of BoHMT1 were not markedly affected in plants exposed to selenium. BoHMT1 expression responded significantly to changes in plant sulfur status. However, its expression was not dramatically affected in plants treated with methionine, SMM, homocysteine, or the heavy metal, cadmium. The differences in the substrate specificity and gene expression in response to changes in plant sulfur and selenium status between BoHMT1 and BoSMT suggest that the enzymes encoded by these two genes play distinct roles in sulfur and selenium metabolism in broccoli.

  3. Cobalamin and folate evaluation: measurement of methylmalonic acid and homocysteine vs vitamin B(12) and folate.

    PubMed

    Klee, G G

    2000-08-01

    Vitamin B(12) and folate are two vitamins that have interdependent roles in nucleic acid synthesis. Deficiencies of either vitamin can cause megaloblastic anemia; however, inappropriate treatment of B(12) deficiency with folate can cause irreversible nerve degeneration. Inadequate folate nutrition during early pregnancy can cause neural tube defects in the developing fetus. In addition, folate and vitamin B(12) deficiency and the compensatory increase in homocysteine are a significant risk factor for cardiovascular disease. Laboratory support for the diagnosis and management of these multiple clinical entities is controversial and somewhat problematic. Automated ligand binding measurements of vitamin B(12) and folate are easiest to perform and widely used. Unfortunately, these tests are not the most sensitive indicators of disease. Measurement of red cell folate is less dependent on dietary fluctuations, but these measurements may not be reliable. Homocysteine and methylmalonic acid are better metabolic indicators of deficiencies at the tissue level. There are no "gold standards" for the diagnosis of these disorders, and controversy exists regarding the best diagnostic approach. Healthcare strategies that consider the impact of laboratory tests on the overall costs and quality of care should consider the advantages of including methylmalonic acid and homocysteine in the early evaluation of patients with suspected deficiencies of vitamin B(12) and folate.

  4. The interactions of fibrinogen and dextrans with erythrocytes

    PubMed Central

    Rampling, M.; Sirs, John A.

    1972-01-01

    1. The rate of packing of erythrocytes in whole blood, under a centrifugal field of 200 g, has been studied using an automatic recording centrifuge. 2. Reduction of the supernatant fibrinogen concentration, by repeatedly washing the cells, lowers the rate of packing and reduces the cell flexibility. 3. Resuspending the cells in their own plasma or in isotonic solutions containing fibrinogen restores their flexibility. 4. Rouleaux formation has been shown to have no effect on the rate of packing by comparison of blood diluted with plasma, isotonic NaCl or Ringer—Locke solutions. While the degree of rouleaux formation varied with the diluent used, the rate of packing and packed cell haematocrit were the same, for the same dilution. 5. Both formalin and dextran altered the degree of rouleaux formation and reduced erythrocyte flexibility. Dextran was found to act indirectly on the erythrocyte flexibility by reducing the plasma fibrinogen concentration. PMID:5046146

  5. Homocysteine Metabolism in ZDF (Type 2) Diabetic Rats

    PubMed Central

    Wijekoon, Enoka P.; Hall, Beatrice; Ratnam, Shobhitha; Brosnan, Margaret E.; Zeisel, Steven H.; Brosnan, John T.

    2008-01-01

    Mild hyperhomocysteinemia is a risk factor for many diseases, including cardiovascular disease. We determined the effects of insulin resistance and of type 2 diabetes on homocysteine (Hcy) metabolism using Zucker diabetic fatty rats (ZDF/Gmi fa/fa and ZDF/Gmi fa/?). Plasma total Hcy was reduced in ZDF fa/fa rats by 24% in the pre-diabetic insulin-resistant stage, while in the frank diabetic stage there was a 59% reduction. Hepatic activities of several enzymes that play a role in the removal of Hcy: cystathionine β-synthase (CBS), cystathionine γ-lyase, and betaine:Hcy methyltransferase (BHMT) were increased as was methionine adenosyltransferase. CBS and BHMT mRNA levels and the hepatic level of S-adenosylmethionine were also increased in the ZDF fa/fa rats. Studies with primary hepatocytes showed that Hcy export and the transsulfuration flux in cells from ZDF fa/fa rats were particularly sensitive to betaine. Interestingly, liver betaine concentration was found to be significantly lower in the ZDf fa/fa rats at both 5 and 11 weeks. These results emphasize the importance of betaine metabolism in determining plasma Hcy levels in type 2 diabetes. PMID:16249451

  6. Extraction, radioiodination, and in vivo catabolism of equine fibrinogen

    SciTech Connect

    Coyne, C.P.; Hornof, W.J.; Kelly, A.B.; O'Brien, T.R.; DeNardo, S.J.

    1985-12-01

    Equine fibrinogen was isolated and aliquots were stored frozen at -70 C before radiolabeling with 125I (half-life = 60.2 days; gamma = 35 keV, using monochloroiodine reagent. Radioiodination efficiencies were 49% to 53%, resulting in a labeled product with 98% protein-bound activity and 91% clottable radioactivity. In 6 equine in vivo investigations, plasma half-lives of 125I-labeled fibrinogen were from 4.1 to 5.2 days, corresponding to a mean daily plasma elimination rate of approximately 15%.

  7. Macrophage-derived IL-18 and increased fibrinogen deposition are age-related inflammatory signatures of vascular remodeling

    PubMed Central

    Rodriguez-Menocal, Luis; Faridi, Mohd Hafeez; Martinez, Laisel; Shehadeh, Lina A.; Duque, Juan C.; Wei, Yuntao; Mesa, Annia; Pena, Angela; Gupta, Vineet; Pham, Si M.

    2014-01-01

    Aging has been associated with pathological vascular remodeling and increased neointimal hyperplasia. The understanding of how aging exacerbates this process is fundamental to prevent cardiovascular complications in the elderly. This study proposes a mechanism by which aging sustains leukocyte adhesion, vascular inflammation, and increased neointimal thickness after injury. The effect of aging on vascular remodeling was assessed in the rat balloon injury model using microarray analysis, immunohistochemistry, and LINCOplex assays. The injured arteries in aging rats developed thicker neointimas than those in younger animals, and this significantly correlated with a higher number of tissue macrophages and increased vascular IL-18. Indeed, IL-18 was 23-fold more abundant in the injured vasculature of aged animals compared with young rats, while circulating levels were similar in both groups of animals. The depletion of macrophages in aged rats with clodronate liposomes ameliorated vascular accumulation of IL-18 and significantly decreased neointimal formation. IL-18 was found to inhibit apoptosis of vascular smooth muscle cells (VSMC) and macrophages, thus favoring both the formation and inflammation of the neointima. In addition, injured arteries of aged rats accumulated 18-fold more fibrinogen-γ than those of young animals. Incubation of rat peritoneal macrophages with immobilized IL-18 increased leukocyte adhesion to fibrinogen and suggested a proinflammatory positive feedback loop among macrophages, VSMC, and the deposition of fibrinogen during neointimal hyperplasia. In conclusion, our data reveal that concentration changes in vascular cytokine and fibrinogen following injury in aging rats contribute to local inflammation and postinjury neointima formation. PMID:24414074

  8. Bacteroides gingivalis and Bacteroides intermedius recognize different sites on human fibrinogen

    SciTech Connect

    Lantz, M.S.; Allen, R.D.; Bounelis, P.; Switalski, L.M.; Hook, M. )

    1990-02-01

    Bacteroides (Porphyromonas) gingivalis and Bacteroides (Porphyromonas) intermedius have been implicated in the etiology of human periodontal diseases. These organisms are able to bind and degrade human fibrinogen, and these interactions may play a role in the pathogenesis of periodontal disease. In attempts to map the bacterial binding sites along the fibrinogen molecule, we have found that strains of B. gingivalis and B. intermedius, respectively, recognize spatially distant and distinct sites on the fibrinogen molecule. Isolated reduced and alkylated alpha-, beta-, and gamma-fibrinogen chains inhibited binding of 125I-fibrinogen to both Bacteroides species in a concentration-dependent manner. Plasmin fragments D and to some extent fragment E, however, produced a concentration-dependent inhibition of 125I-fibrinogen binding to B. intermedius strains but did not affect binding of 125I-fibrinogen to B. gingivalis strains. Radiolabeled fibrinogen chains and fragments were compared with 125I-fibrinogen with respect to specificity and reversibility of binding to bacteria. According to these criteria, gamma chain most closely resembled the native fibrinogen molecule in behavior toward B. gingivalis strains and fragments D most closely resembled fibrinogen in behavior toward B. intermedius strains. The ability of anti-human fibrinogen immunoglobulin G (IgG) to inhibit binding of 125I-fibrinogen to B. intermedius strains was greatly reduced by absorbing the IgG with fragments D. Absorbing the IgG with fragments D had no effect on the ability of the antibody to inhibit binding of 125I-fibrinogen to B. gingivalis strains. A purified staphylococcal fibrinogen-binding protein blocked binding of 125I-fibrinogen to B. intermedius strains but not to B. gingivalis strains.

  9. Bacteroides gingivalis and Bacteroides intermedius recognize different sites on human fibrinogen.

    PubMed Central

    Lantz, M S; Allen, R D; Bounelis, P; Switalski, L M; Hook, M

    1990-01-01

    Bacteroides (Porphyromonas) gingivalis and Bacteroides (Porphyromonas) intermedius have been implicated in the etiology of human periodontal diseases. These organisms are able to bind and degrade human fibrinogen, and these interactions may play a role in the pathogenesis of periodontal disease. In attempts to map the bacterial binding sites along the fibrinogen molecule, we have found that strains of B. gingivalis and B. intermedius, respectively, recognize spatially distant and distinct sites on the fibrinogen molecule. Isolated reduced and alkylated alpha-, beta-, and gamma-fibrinogen chains inhibited binding of 125I-fibrinogen to both Bacteroides species in a concentration-dependent manner. Plasmin fragments D and to some extent fragment E, however, produced a concentration-dependent inhibition of 125I-fibrinogen binding to B. intermedius strains but did not affect binding of 125I-fibrinogen to B. gingivalis strains. Radiolabeled fibrinogen chains and fragments were compared with 125I-fibrinogen with respect to specificity and reversibility of binding to bacteria. According to these criteria, gamma chain most closely resembled the native fibrinogen molecule in behavior toward B. gingivalis strains and fragments D most closely resembled fibrinogen in behavior toward B. intermedius strains. The ability of anti-human fibrinogen immunoglobulin G (IgG) to inhibit binding of 125I-fibrinogen to B. intermedius strains was greatly reduced by absorbing the IgG with fragments D. Absorbing the IgG with fragments D had no effect on the ability of the antibody to inhibit binding of 125I-fibrinogen to B. gingivalis strains. A purified staphylococcal fibrinogen-binding protein blocked binding of 125I-fibrinogen to B. intermedius strains but not to B. gingivalis strains. PMID:2404954

  10. Acute homocysteine administration impairs memory consolidation on inhibitory avoidance task and decreases hippocampal brain-derived neurotrophic factor immunocontent: prevention by folic acid treatment.

    PubMed

    Matté, C; Pereira, L O; Dos Santos, T M; Mackedanz, V; Cunha, A A; Netto, C A; Wyse, A T S

    2009-11-10

    In the present study, we first investigated the effect of single homocysteine administration on consolidation of short- and long-term memories of inhibitory avoidance task in Wistar rats. We also measured brain-derived neurotrophic factor levels in the hippocampus and parietal cortex of rats. The influence of pretreatment with folic acid on behavioral and biochemical effects elicited by homocysteine was also studied. Wistar rats were subjected to a folic acid or saline pretreatment from their 22(nd) to 28(th) day of life; 12 h later they were submitted to a single administration of homocysteine or saline. For motor activity and memory evaluation we performed open-field and inhibitory avoidance tasks. Hippocampus and parietal cortex were obtained for brain-derived neurotrophic factor immunocontent determination. Results showed that homocysteine impaired short- and long-term memories and reduced brain-derived neurotrophic factor levels in the hippocampus. Pretreatment with folic acid prevented both the memory deficit and the reduction in the brain-derived neurotrophic factor immunocontent induced by homocysteine injection. Further studies are required to determine the entire mechanism by which folic acid acts and its potential therapeutic use for memory impairment prevention in homocystinuric patients.

  11. Vitamin B-6 Supplementation Could Mediate Antioxidant Capacity by Reducing Plasma Homocysteine Concentration in Patients with Hepatocellular Carcinoma after Tumor Resection.

    PubMed

    Cheng, Shao-Bin; Lin, Ping-Ting; Liu, Hsiao-Tien; Peng, Yi-Shan; Huang, Shih-Chien; Huang, Yi-Chia

    2016-01-01

    Vitamin B-6 has a strong antioxidative effect. It would be useful to determine whether vitamin B-6 supplementation had effects on antioxidant capacities in patients with hepatocellular carcinoma (HCC) who had recently undergone tumor resection. Thirty-three HCC patients were randomly assigned to either the placebo (n = 16) group or the vitamin B-6 50 mg/d (n = 17) group for 12 weeks. Plasma pyridoxal 5'-phosphate, homocysteine, indicators of oxidative stress, and antioxidant capacities were measured. Plasma homocysteine in the vitamin B-6 group was significantly decreased at week 12, while the level of trolox equivalent antioxidant capacity (TEAC) was significantly increased at the end of the intervention period. Vitamin B-6 supplementation had a significant reducing effect on the change of plasma homocysteine (β = -2.4, p = 0.02) but not on the change of TEAC level after adjusting for potential confounders. The change of plasma homocysteine was significantly associated with the change of TEAC after adjusting for potential confounders (β = -162.0, p = 0.03). Vitamin B-6 supplementation seemed to mediate antioxidant capacity via reducing plasma homocysteine rather than having a direct antioxidative effect in HCC patients who had recently undergone tumor resection. The clinical trial number is NCT01964001, ClinicalTrials.gov. PMID:27051670

  12. Influence of a constant magnetic field on the fibrinogen-fibrin system. [in blood coagulation process

    NASA Technical Reports Server (NTRS)

    Matskevichene, V. B.; Platonova, A. T.

    1974-01-01

    The effect of a constant magnetic field with a strength of 2500 oersteds on the fibrinogen-fibrin system was studied in the organism of healthy rabbits with exposure times of 1 and 5 hours. The results obtained indicate disruptions in the stage of conversion of fibrinogen to fibrin and an increase in the amount of fibrinogen.

  13. Fibrinogen concentrate as first-line therapy in aortic surgery reduces transfusion requirements in patients with platelet counts over or under 100×109/L

    PubMed Central

    Solomon, Cristina; Rahe-Meyer, Niels

    2015-01-01

    Background Administration of fibrinogen concentrate, targeting improved maximum clot firmness (MCF) of the thromboelastometric fibrin-based clot quality test (FIBTEM) is effective as first-line haemostatic therapy in aortic surgery. We performed a post-hoc analysis of data from a randomised, placebo-controlled trial of fibrinogen concentrate, to investigate whether fibrinogen concentrate reduced transfusion requirements for patients with platelet counts over or under 100×109/L. Material and methods Aortic surgery patients with coagulopathic bleeding after cardiopulmonary bypass were randomised to receive either fibrinogen concentrate (n=29) or placebo (n=32). Platelet count was measured upon removal of the aortic clamp, and coagulation and haematology parameters were measured peri-operatively. Transfusion of allogeneic blood components was recorded and compared between groups. Results After cardiopulmonary bypass, haemostatic and coagulation parameters worsened in all groups; plasma fibrinogen level (determined by the Clauss method) decreased by 43–58%, platelet count by 53–64%, FIBTEM maximum clot firmness (MCF) by 38–49%, FIBTEM maximum clot elasticity (MCE) by 43–54%, extrinsically activated test (EXTEM) MCF by 11–22%, EXTEM MCE by 25–41% and the platelet component of the clot by 23–39%. Treatment with fibrinogen concentrate (mean dose 7–9 g in the 4 groups) significantly reduced post-operative allogeneic blood component transfusion requirements when compared to placebo both for patients with a platelet count ≥100×109/L and for patients with a platelet count <100×109/L. Discussion FIBTEM-guided administration of fibrinogen concentrate reduced transfusion requirements when used as a first-line haemostatic therapy during aortic surgery in patients with platelet counts over or under 100×109/L. PMID:25369608

  14. 21 CFR 864.7340 - Fibrinogen determination system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Fibrinogen determination system. 864.7340 Section 864.7340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  15. 21 CFR 864.7340 - Fibrinogen determination system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Fibrinogen determination system. 864.7340 Section 864.7340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  16. 21 CFR 864.7340 - Fibrinogen determination system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Fibrinogen determination system. 864.7340 Section 864.7340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  17. 21 CFR 864.7340 - Fibrinogen determination system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Fibrinogen determination system. 864.7340 Section 864.7340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  18. Air Pollution and Inflammation (Interleukin-6, C-Reactive Protein, Fibrinogen) in Myocardial Infarction Survivors

    PubMed Central

    Rückerl, Regina; Greven, Sonja; Ljungman, Petter; Aalto, Pasi; Antoniades, Charalambos; Bellander, Tom; Berglind, Niklas; Chrysohoou, Christina; Forastiere, Francesco; Jacquemin, Bénédicte; von Klot, Stephanie; Koenig, Wolfgang; Küchenhoff, Helmut; Lanki, Timo; Pekkanen, Juha; Perucci, Carlo A.; Schneider, Alexandra; Sunyer, Jordi; Peters, Annette

    2007-01-01

    Background Numerous studies have found that ambient air pollution has been associated with cardiovascular disease exacerbation. Objectives Given previous findings, we hypothesized that particulate air pollution might induce systemic inflammation in myocardial infarction (MI) survivors, contributing to an increased vulnerability to elevated concentrations of ambient particles. Methods A prospective longitudinal study of 1,003 MI survivors was performed in six European cities between May 2003 and July 2004. We compared repeated measurements of interleukin 6 (IL-6), fibrinogen, and C-reactive protein (CRP) with concurrent levels of air pollution. We collected hourly data on particle number concentrations (PNC), mass concentrations of particulate matter (PM) < 10 μm (PM10) and < 2.5 μm (PM2.5), gaseous pollutants, and meteorologic data at central monitoring sites in each city. City-specific confounder models were built for each blood marker separately, adjusting for meteorology and time-varying and time-invariant covariates. Data were analyzed with mixed-effects models. Results Pooled results show an increase in IL-6 when concentrations of PNC were elevated 12–17 hr before blood withdrawal [percent change of geometric mean, 2.7; 95% confidence interval (CI), 1.0–4.6]. Five day cumulative exposure to PM10 was associated with increased fibrinogen concentrations (percent change of arithmetic mean, 0.6; 95% CI, 0.1–1.1). Results remained stable for smokers, diabetics, and patients with heart failure. No consistent associations were found for CRP. Conclusions Results indicate an immediate response to PNC on the IL-6 level, possibly leading to the production of acute-phase proteins, as seen in increased fibrinogen levels. This might provide a link between air pollution and adverse cardiac events. PMID:17637925

  19. Evaluation of Fibrinogen Self-assembly: Role of its alphaC Region

    SciTech Connect

    J Koo; M Rafailovich; L Medved; G Tsurupa; B Kudryk; y Liu; D Galanakis

    2011-12-31

    Background: Exposure of cryptic, functional sites on fibrinogen upon its adsorption to hydrophobic surfaces of biomaterials has been linked to an inflammatory response and fibrosis. Such adsorption also induces ordered fibrinogen aggregation which is poorly understood. Objective: To investigate hydrophobic surface-induced fibrinogen aggregation. Methods: Contact and lateral force scanning probe microscopy, yielding topography, image dimensions and fiber elastic modulus measurements were used along with transmission and scanning electron microscopy. Fibrinogen aggregation was induced under non-enzymatic conditions by adsorption on a trioctyl-surface monolayer (trioctylmethylamine) grafted onto silica clay plates. Results: A more than one molecule thick coating was generated by adsorption on the plate from 100 to 200 {mu}g mL{sup -1} fibrinogen solutions, and three-dimensional networks formed from 4 mg mL{sup -1} fibrinogen incubated with uncoated or fibrinogen-coated plates. Fibrils appeared laterally assembled into branching and overlapping fibers whose heights from the surface ranged from approximately 3 to 740 nm. The elastic modulus of fibrinogen fibers was 1.55 MPa. No fibrils formed when fibrinogen lacking {alpha}C-domains was used as a coating or was incubated with intact fibrinogen-coated plates, or when the latter plates were sequentially incubated with anti-A{alpha}529-539 mAb and intact fibrinogen. When an anti-A{alpha}241-476 mAb was used instead, fine, long fibers formed. Similarly, sequential incubations of fibrinogen-coated plates with recombinant {alpha}C-domain (A{alpha}392-610 fragment) or {alpha}C-connector (A{alpha}221-372 fragment) and fibrinogen resulted in distinctly fine fiber networks. Conclusions: Adsorption-induced fibrinogen self-assembly is initiated by a more than one molecule-thick surface layer and eventuates in three-dimensional networks whose formation requires fibrinogen with intact {alpha}C-domains.

  20. Evaluation of Fibrinogen Self-assembly: Role of its αC Region

    PubMed Central

    Koo, Jaseung; Rafailovich, Miriam H.; Medved, Leonid; Tsurupa, Galina; Kudryk, Bohdan J.; Liu, Ying; Galanakis, Dennis K.

    2010-01-01

    SUMMARY Background Exposure of cryptic, functional sites on fibrinogen upon its adsorption to hydrophobic surfaces of biomaterials have been linked to inflammatory response and fibrosis. Such adsorption also induces ordered fibrinogen aggregation which is poorly understood. Objective To investigate hydrophobic surface-induced fibrinogen aggregation. Methods: Contact and lateral force scanning probe microscopy, yielding topography, image dimensions, and fiber elastic modulus measurements were used along with transmission and scanning electron microscopy. Fibrinogen aggregation was induced under non-enzymatic conditions by adsorption on a trioctyl-surface monolayer (trioctylmethylamine) grafted onto silica clay plates. Results A more than one molecule thick coating was generated by adsorption on the plate from 100–200 μg/ml fibrinogen solutions, and three-dimensional networks formed from 4 mg/ml fibrinogen incubated with uncoated or fibrinogen-coated plates. Fibrils appeared laterally assembled into branching and overlapping fibers whose heights from surface ranged from ~3 to 740 nm. The elastic modulus of fibrinogen fibers was 1.55 MPa. No fibrils formed when fibrinogen lacking αC-domains was used as coating or was incubated with intact fibrinogen-coated plates, or when the latter plates were sequentially incubated with anti-Aα529–539 mAb and intact fibrinogen. When an anti-Aα241–476 mAb was used instead, fine, long fibers formed. Similarly, sequential incubations of fibrinogen-coated plates with recombinant αC-domain (Aα392–610 fragment) or αC-connector (Aα221–372 fragment) and fibrinogen resulted in distinctly fine fiber networks. Conclusions Adsorption-induced fibrinogen self-assembly is initiated by a more than one molecule-thick surface layer and eventuates in three-dimensional networks whose formation requires fibrinogen with intact αC-domains. PMID:20880206

  1. Role of homocysteine in the development of cardiovascular disease.

    PubMed

    Ganguly, Paul; Alam, Sreyoshi Fatima

    2015-01-10

    It is well known that neuronal damage following a stroke has been attributed to the over stimulation of excitatory amino acids such as glutamate and aspartate through activation of NMDA receptors. The brain is exposed to most of the constituents of plasma including homocysteine as a result of the disruption of the blood-brain barrier after stroke, head trauma and stress. The question, therefore, arises as to whether or not homocysteine is able to selectively stimulate the release of excitatory amino acids in stroke. This review article will address the importance of homocysteine in nervous system specifically how these amino acids may trigger the release of catecholamines. Our data will thus strengthen the view that a mechanism for the association of hyperhomocysteinemia with increased brain lesion in stroke. As hypothalamus also controls the cardiac function via sympathetic system, the contractility of heart will be compromised. Homocysteine is also known to mediate cardiovascular problems by its adverse effects on cardiovascular endothelium and smooth muscle cells with resultant alterations in subclinical arterial structure and function. The present review will thus summarize both central and peripheral effects of homocysteine and will highlight some of the controversies associated with hyperhomocysteinemia-induced cardiovascular problems.

  2. Common genetic loci influencing plasma homocysteine concentrations and their effect on risk of coronary artery disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The strong observational association between total homocysteine (tHcy) concentrations and risk of coronary artery disease (CAD) and the null associations in the homocysteine-lowering trials have prompted the need to identify genetic variants associated with homocysteine concentrations and risk of CA...

  3. Clinical significance of determining plasma homocysteine: case-control study on arterial and venous thrombotic patients

    PubMed Central

    Vučković, Biljana A.; Čabarkapa, Velibor S.; Ilić, Tatjana A.; Salatić, Iva R.; Lozanov-Crvenković, Zagorka S.; Mitić, Gorana P.

    2013-01-01

    Aim To determine the differences in plasma homocysteine levels between three MTHFR 677 genotype subgroups in patients with thrombosis and in controls, as well as between patients with thrombosis and controls with the same MTHFR 677 genotype. Methods This case-control study was conducted in Clinical Center of Vojvodina, Novi Sad, from June to December 2011. We included 65 patients with either arterial or venous thrombosis (mean age, 40.97 ± 11.38 years) and 65 controls with no history or clinical evidence of any thrombotic event (mean age, 41.23 ± 11.12 years). Patients and controls were age- and sex-matched. Results In comparison with controls, thrombotic patients had significantly higher homocysteine levels (12.81 ± 4.94 µmol/L vs 9.82 ± 3.68 µmol/L; P < 0.001) and significantly higher incidence of hyperhomocysteinemia (55% vs 22%; P < 0.001; odds ratio [OR] = 4.521). There were no significant differences in homocysteine levels between homozygous carriers, heterozygous carriers, and non-carriers of the MTHFR 677 mutation in either thrombotic patients (12.97 ± 5.40 µmol/L vs 12.55 ± 5.71 µmol/L vs 13.27 ± 1.71 µmol/L; P = 0.100) or controls (10.07 ± 2.50 µmol/L vs 10.25 ± 4.84 µmol/L vs 9.20 ± 2.44 µmol/L; P = 0.651). However, in comparison with controls, homozygous carriers in thrombotic patient group did not have significantly higher levels of homocysteine (12.97 ± 5.40 µmol/L vs 10.07 ± 2.50 µmol/L; P = 0.072), but heterozygous carriers (12.55 ± 5.71 µmol/L vs 10.25 ± 4.84 µmol/L; P = 0.020) and non-carriers (13.27 ± 1.71 µmol/L vs 9.20 ± 2.44 µmol/L; P < 0.001) did. There was no significant difference in homocysteine levels between patients with arterial and venous thrombosis (12.76 ± 3.60 µmol/L vs 12.86 ± 5.51 µmol/L; P = 0.990) and between patients with one thrombotic event and those with recurrent thrombotic events

  4. Evaluation of Serum Homocysteine, High-Sensitivity CRP, and RBC Folate in Patients with Alopecia Areata

    PubMed Central

    Yousefi, Maryam; Namazi, Mohammad Reza; Rahimi, Hoda; Younespour, Shima; Ehsani, Amir Houshang; Shakoei, Safoura

    2014-01-01

    Introduction: Alopecia areata (AA) is a common type of hair loss with an autoimmune basis. As the role of homocysteine (Hcys), folate, and CRP has been considered in some autoimmune diseases. Objectives: To evaluate homocysteine, folate and CRP level in AA. Methods: This study was performed on 29 patients who had AA for at least 6 months affecting more than 20% of scalp, and 32 healthy controls. Levels of serum Hcys, blood high-sensitivity CRP, and RBC folate were measured in all subjects. Results: The mean level of RBC folate was significantly lower in the patient group than that in controls (P < 0.001). Also, the level of RBC folate was significantly lower in patients with extensive forms of disease (alopecia totalis/alopecia universalis) in comparison with more localized form (patchy hair loss) (P < 0.05). Patients with higher “Severity of Alopecia Total” (SALT) score had lower RBC folate, as well. Serum Hcys and blood high-sensitivity CRP levels did not show a significant difference in two groups. Conclusion: Patients with alopecia areata have lower level of RBC folate which is in negative correlation with both severity and extension of AA. PMID:25484412

  5. Specific cell components of Bacteroides gingivalis mediate binding and degradation of human fibrinogen

    SciTech Connect

    Lantz, M.S.; Allen, R.D.; Vail, T.A.; Switalski, L.M.; Hook, M. )

    1991-01-01

    Bacteroides (Porphyromonas) gingivalis, which has been implicated as an etiologic agent in human periodontal diseases, has been shown to bind and degrade human fibrinogen. B. gingivalis strains bind fibrinogen reversibly and with high affinity and bind to a specific region of the fibrinogen molecule that appears to be located between the D and E domains. The authors now report that human fibrinogen is bound and then degraded by specific B. gingivalis components that appear to be localized at the cell surface. Fibrinogen binding to bacterial cells occurred at 4, 22, and 37{degree}C. A functional fibrinogen-binding component (M{sub r}, 150 000) was identified when sodium dodecyl sulfate-solubilized bacteria were fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to nitrocellulose membranes, and probed with {sup 125}I-fibrinogen. Fibrinogen degradation did not occur at 4{degree}C but did occur at 22 and 37{degree}C. When bacteria and iodinated fibrinogen were incubated at 37{degree}C, two major fibrinogen fragments (M{sub r}, 97 000 and 50 000) accumulated in incubation mixture supernatant fractions. Two major fibrinogen-degrading components (M{sub r}, 120 000 and 150 000) have been identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in substrate-containing gels. Fibrinogen degradation by the M{sub r}-120 000 and -150 000 proteases was enhanced by reducing agents, completely inhibited by N-{alpha}-p-tosyl-L-lysyl chloromethyl ketone, and partially inhibited by n-ethyl maleimide, suggesting that these enzymes are thiol-dependent proteases with trypsinlike substrate specificity. The fibrinogen-binding component could be separated from the fibrinogen-degrading components by selective solubilization of bacteria in sodium deoxycholate.

  6. Specific cell components of Bacteroides gingivalis mediate binding and degradation of human fibrinogen.

    PubMed Central

    Lantz, M S; Allen, R D; Vail, T A; Switalski, L M; Hook, M

    1991-01-01

    Bacteroides (Porphyromonas) gingivalis, which has been implicated as an etiologic agent in human periodontal diseases, has been shown to bind and degrade human fibrinogen. B. gingivalis strains bind fibrinogen reversibly and with high affinity and bind to a specific region of the fibrinogen molecule that appears to be located between the D and E domains (M. S. Lantz, R. D. Allen, P. Bounelis, L. M. Switalski, and M. Hook, J. Bacteriol. 172:716-726, 1990). We now report that human fibrinogen is bound and then degraded by specific B. gingivalis components that appear to be localized at the cell surface. Fibrinogen binding to bacterial cells occurred at 4, 22, and 37 degrees C. A functional fibrinogen-binding component (Mr, 150,000) was identified when sodium dodecyl sulfate-solubilized bacteria were fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to nitrocellulose membranes, and probed with 125I-fibrinogen. Fibrinogen degradation did not occur at 4 degrees C but did occur at 22 and 37 degrees C. When bacteria and iodinated fibrinogen were incubated at 37 degrees C, two major fibrinogen fragments (Mr, 97,000 and 50,000) accumulated in incubation mixture supernatant fractions. Two major fibrinogen-degrading components (Mr, 120,000 and 150,000) have been identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in substrate-containing gels. Fibrinogen degradation by the Mr-120,000 and -150,000 proteases was enhanced by reducing agents, completely inhibited by N-alpha-p-tosyl-L-lysyl chloromethyl ketone, and partially inhibited by n-ethyl maleimide, suggesting that these enzymes are thiol-dependent proteases with trypsinlike substrate specificity. The fibrinogen-binding component could be separated from the fibrinogen-degrading components by selective solubilization of bacteria in sodium deoxycholate. Images PMID:1987144

  7. Time-dependent association between platelet-bound fibrinogen and the Triton X-100 insoluble cytoskeleton

    SciTech Connect

    Peerschke, E.I. )

    1991-02-01

    Previous studies indicated a correlation between the formation of EDTA-resistant (irreversible) platelet-fibrinogen interactions and platelet cytoskeleton formation. The present study explored the direct association of membrane-bound fibrinogen with the Triton X-100 insoluble cytoskeleton of aspirin-treated, gel-filtered platelets, activated but not aggregated with 20 mumol/L adenosine diphosphate (ADP) or 150 mU/mL human thrombin (THR) when bound fibrinogen had become resistant to dissociation by EDTA. Conversion of exogenous 125I-fibrinogen to fibrin was prevented by adding Gly-Pro-Arg and neutralizing THR with hirudin before initiating binding studies. After 60 minutes at 22 degrees C, the cytoskeleton of ADP-treated platelets contained 20% +/- 12% (mean +/- SD, n = 14) of membrane-bound 125I-fibrinogen, representing 10% to 50% of EDTA-resistant fibrinogen binding. The THR-activated cytoskeleton contained 45% +/- 15% of platelet bound fibrinogen, comprising 80% to 100% of EDTA-resistant fibrinogen binding. 125I-fibrinogen was not recovered with platelet cytoskeletons if binding was inhibited by the RGDS peptide, excess unlabeled fibrinogen, or disruption of the glycoprotein (GP) IIb-IIIa complex by EDTA-treatment. Both development of EDTA-resistant fibrinogen binding and fibrinogen association with the cytoskeleton were time dependent and reached maxima 45 to 60 minutes after fibrinogen binding to stimulated platelets. Although a larger cytoskeleton formed after platelet stimulation with thrombin as compared with ADP, no change in cytoskeleton composition was noted with development of EDTA-resistant fibrinogen binding.

  8. Plasma homocysteine concentration changes after renal transplantation in children.

    PubMed

    Merouani, Aicha; Delvin, Edgar E; Genest, Jacques; Rozen, Rima; Lambert, Marie

    2002-07-01

    Hyperhomocysteinemia, a risk factor for vascular disease, is found in children as well as in 80% of adult patients with end-stage renal disease. The aim of this study was to assess the changes in plasma homocysteine concentrations after renal transplantation (RT). Plasma homocysteine, vitamin B(12), and folate concentrations were prospectively measured in six patients at three points, before and post transplantation (6 months, 4 years), and compared with controls using standardized scores (Z score) for each of these parameters. Folic acid supplementation was introduced after the evaluation at 6 months. Patients had elevated median plasma homocysteine Z scores during dialysis (4.12). When assessed at 6 months and 4 years, median plasma homocysteine Z scores were, respectively, 2.35 and 0.29. Median folate Z scores were 1.89 during dialysis, -0.26 at 6 months, and 3.26 at 4 years post RT. Median vitamin B(12) Z score was 2.12 during dialysis, 0.58 at 6 months, and -0.07 at 4 years post RT. Glomerular filtration rate (GFR) improved after RT, with median GFR of 84.5 ml/min per 1.73 m(2) at 6 months. This stabilized to a value of 70.5 ml/min per 1.73 m(2) at 4 years. When comparing values before and after RT at 6 months, changes were observed only for GFR ( P<0.03) and vitamin B(12) ( P<0.05). There were no changes in plasma homocysteine, folate, and serum albumin. At 4 years, a significant decrease in plasma homocysteine was observed ( P<0.05) with increased GFR ( P<0.03). No significant changes were observed in plasma albumin, folate, and vitamin B(12) concentrations. In conclusion, elevated plasma homocysteine in children during dialysis persists after RT despite a significant improvement in renal function. However, normalization was attained when patients were supplemented with folic acid. Further controlled studies are required to evaluate the determinants and treatment of elevated plasma homocysteine in pediatric transplant patients. PMID:12172766

  9. Homocysteine, B-vitamins and CVD.

    PubMed

    McNulty, Helene; Pentieva, Kristina; Hoey, Leane; Ward, Mary

    2008-05-01

    There is considerable interest in plasma homocysteine (tHcy) as a CVD risk factor. Although the secondary prevention trials published to date have been inconclusive in confirming a benefit of tHcy-lowering treatment with B-vitamins on CVD events generally, such studies are widely recognised to have been insufficiently powered to detect a significant effect for the predicted magnitude of association between tHcy and heart disease risk, and therefore cannot be interpreted as evidence that no relationship exists. In fact, a recent meta-analysis of clinical trials has confirmed that folic acid supplementation reduces the risk of stroke, particularly in individuals without a history of stroke. Evidence supporting a causal relationship between elevated tHcy and heart disease also comes from genetic studies. The most important genetic determinant of tHcy in the general population is the common C677T variant in methylenetetrahydrofolate reductase (MTHFR) that results in higher tHcy. Individuals with the homozygous mutant (TT) genotype have a significantly higher (14-21%) risk of heart disease. Plasma tHcy is very responsive to intervention with the B-vitamins required for its metabolism, in particular folic acid, and to a lesser extent vitamins B12 and B6. Thus, although primarily aimed at reducing neural-tube defects, folic acid fortification may have an important role in the primary prevention of CVD via tHcy lowering. Besides folate, riboflavin is required as a cofactor for MTHFR and enhanced riboflavin status results in a marked lowering in tHcy specifically in individuals with the TT genotype, presumably by neutralising the variant form of the enzyme. About 10% of the UK and Irish populations have the TT genotype. In the present paper the potential role of folate and related B-vitamins in the primary prevention of CVD and the implications for nutrition policy are explored. PMID:18412997

  10. Hepatic Fibrinogen Storage Disease in a Patient with Hypofibrinogenemia: Report of a Case with a Missense Mutation of the FGA Gene.

    PubMed

    Lee, Michael J; Venick, Robert; Bhuta, Sunita; Li, Xinmin; Wang, Hanlin L

    2015-11-01

    We report a 9-year-old patient with abnormal liver tests found incidentally during routine bloodwork as part of a preoperative evaluation for excision of a benign cyst. A liver biopsy demonstrated hepatocytes to have pale and expanded cytoplasm that contained multiple vague globular eosinophilic inclusions. Electron microscopy showed fingerprint-like structures in the dilated cisternae of the rough endoplasmic reticulum, characteristic of fibrinogen. Whole exome sequencing identified a heterozygous missense mutation at codon 35 of the fibrinogen α (FGA) gene. No mutation was identified in the β or γ chains. His plasma fibrinogen levels were found to be decreased to 85 mg/dL (normal range 215-464). His family history was pertinent for his mother and maternal grandfather with hypofibrinogenemia. He had not had any significant bleeding episodes except for minor bruising over the shins. This case illustrates a rare etiology of storage disease that causes abnormal liver function tests. PMID:26676819

  11. Plasma total homocysteine status of vegetarians compared with omnivores: a systematic review and meta-analysis.

    PubMed

    Obersby, Derek; Chappell, David C; Dunnett, Andrew; Tsiami, Amalia A

    2013-03-14

    There is strong evidence indicating that elevated plasma total homocysteine (tHcy) levels are a major independent biomarker and/or a contributor to chronic conditions, such as CVD. A deficiency of vitamin B₁₂ can elevate homocysteine. Vegetarians are a group of the population who are potentially at greater risk of vitamin B₁₂ deficiency than omnivores. This is the first systematic review and meta-analysis to appraise a range of studies that compared the homocysteine and vitamin B₁₂ levels of vegetarians and omnivores. The search methods employed identified 443 entries, from which, by screening using set inclusion and exclusion criteria, six eligible cohort case studies and eleven cross-sectional studies from 1999 to 2010 were revealed, which compared concentrations of plasma tHcy and serum vitamin B₁₂ of omnivores, lactovegetarians or lacto-ovovegetarians and vegans. Of the identified seventeen studies (3230 participants), only two studies reported that vegan concentrations of plasma tHcy and serum vitamin B₁₂ did not differ from omnivores. The present study confirmed that an inverse relationship exists between plasma tHcy and serum vitamin B₁₂, from which it can be concluded that the usual dietary source of vitamin B₁₂ is animal products and those who choose to omit or restrict these products are destined to become vitamin B₁₂ deficient. At present, the available supplement, which is usually used for fortification of food, is the unreliable cyanocobalamin. A well-designed study is needed to investigate a reliable and suitable supplement to normalise the elevated plasma tHcy of a high majority of vegetarians. This would fill the gaps in the present nutritional scientific knowledge. PMID:23298782

  12. Plasma total homocysteine status of vegetarians compared with omnivores: a systematic review and meta-analysis.

    PubMed

    Obersby, Derek; Chappell, David C; Dunnett, Andrew; Tsiami, Amalia A

    2013-03-14

    There is strong evidence indicating that elevated plasma total homocysteine (tHcy) levels are a major independent biomarker and/or a contributor to chronic conditions, such as CVD. A deficiency of vitamin B₁₂ can elevate homocysteine. Vegetarians are a group of the population who are potentially at greater risk of vitamin B₁₂ deficiency than omnivores. This is the first systematic review and meta-analysis to appraise a range of studies that compared the homocysteine and vitamin B₁₂ levels of vegetarians and omnivores. The search methods employed identified 443 entries, from which, by screening using set inclusion and exclusion criteria, six eligible cohort case studies and eleven cross-sectional studies from 1999 to 2010 were revealed, which compared concentrations of plasma tHcy and serum vitamin B₁₂ of omnivores, lactovegetarians or lacto-ovovegetarians and vegans. Of the identified seventeen studies (3230 participants), only two studies reported that vegan concentrations of plasma tHcy and serum vitamin B₁₂ did not differ from omnivores. The present study confirmed that an inverse relationship exists between plasma tHcy and serum vitamin B₁₂, from which it can be concluded that the usual dietary source of vitamin B₁₂ is animal products and those who choose to omit or restrict these products are destined to become vitamin B₁₂ deficient. At present, the available supplement, which is usually used for fortification of food, is the unreliable cyanocobalamin. A well-designed study is needed to investigate a reliable and suitable supplement to normalise the elevated plasma tHcy of a high majority of vegetarians. This would fill the gaps in the present nutritional scientific knowledge.

  13. New method for determining thrombin-clottable fibrinogen.

    PubMed

    Frigola, A; Angeloni, S; Cerqueti, A R

    1977-11-01

    We describe a new method for determination of thrombin-clottable fibrinogen, which eliminates the systematic error caused by occlusion of other serum proteins in the fibrin clot and reduces the sensitivity to high concentrations of fibrin degradation products. Essentially, the method consists of densitometric quantitation of the fibrin band after a standard electrophoresis run of plasma, thrombin fixation of the fibrinogen, and removal of the non-clotted proteins by washing in saline. The procedure shows good precision and gives results that are accurate, significantly correlate with results for the classical thrombin clotting method (r = 0.92, P less than .001), and are not affected by fibrin degradation product concentrations up to 900 mg/liter. These characteristics make the method especially valuable in establishing fibrogen concentration in patients who are undergoing thrombolytic therapy.

  14. Long‐term effect of Helicobacter pylori eradication on plasma homocysteine in elderly patients with cobalamin deficiency

    PubMed Central

    Marino, Marília Campos Abreu; de Oliveira, Celso Affonso; Rocha, Andreia Maria Camargos; Rocha, Gifone Aguiar; Clementino, Nelma Cristina Diogo; Antunes, Leonardo França; Oliveira, Ricardo Araújo; Martins, Almir Sousa; Del Puerto, Helen Lima; D'Almeida, Vânia; Galdieri, Luciano; Pedroso, Ênio Roberto Pietra; Cabral, Mônica Maria Demas Álvares; Nogueira, Ana Margarida Miguel Ferreira; Queiroz, Dulciene Maria Magalhães

    2007-01-01

    Background Helicobacter pylori gastritis may lead to impairment of the production of pepsinogen and acid, which are essential to cobalamin absorption. In turn, cobalamin deficiency leads to hyperhomocysteinaemia, a risk factor for cardio and cerebrovascular diseases. Aim To evaluate the effect of H pylori eradication on plasma homocysteine levels in elderly patients. Patients Sixty‐two H pylori‐positive elderly patients with cobalamin deficiency were prospectively studied. Methods Homocysteine and cobalamin concentrations were determined before, 6 and 12 months after H pylori eradication. Results Corpus atrophy was observed in a few patients; otherwise, in most of them, the degree of corpus gastritis was moderate to severe. The initial homocysteine mean (SD) levels decreased from 41.0 (27.1) to 21.6 (10.1) μmol/l at the 6 month follow‐up (p<0.001) and to 13.1 (3.8) μmol/l 12 months after H pylori eradication (p<0.001). Conversely, initial cobalamin mean levels increased from 145.5 (48.7) pmol/l to 209.8 (87.1) pmol/l and to 271.2 (140.8) pmol/l, 6 and 12 months after treatment, respectively (p<0.001 for both). Although the erythrocyte mean corpuscular volume was within reference intervals, it decreased significantly 6 (p = 0.002) and 12 (p<0.001) months after treatment. Conclusions The results of the current study demonstrated that the eradication of H pylori in elderly patients with cobalamin deficiency is followed by increasing of cobalamin and decreasing of homocysteine blood levels. PMID:17005765

  15. Novel locus for fibrinogen in 3' region of LEPR gene in island population of Vis (Croatia).

    PubMed

    Tomas, Željka; Petranović, Matea Zajc; Škarić-Jurić, Tatjana; Barešić, Ana; Salihović, Marijana Peričić; Narančić, Nina Smolej

    2014-11-01

    Leptin, a possible mediator between energy homeostasis, inflammation and cardiovascular disease (CVD), acts via leptin receptors. We investigated association of single-nucleotide polymorphisms (SNPs) and haplotypes of the leptin receptor gene (LEPR) with several CVD risk factors: body mass index, waist circumference (WC), serum lipids, fibrinogen and C-reactive protein levels. Thirty-one SNPs in and near LEPR gene were analyzed in 986 inhabitants of the island of Vis, Croatia and 29 SNPs in the inland sample (N=499). We assessed linkage disequilibrium (LD), SNP and haplotype associations with the selected phenotypes. rs4291477 significantly associated with fibrinogen (P=0.003) and rs7539471 marginally significantly with high-density lipoprotein (P=0.004), but only in the Vis sample, while rs10493384 marginally significantly associated with triglyceride levels (P=0.006) in the inland sample. SNPs were grouped into eight LD blocks in Vis and in seven blocks in the inland population. Haplotype A-C-A-A-G-A in block 5 in Vis (rs1782754, rs1171269, rs1022981, rs6673324, rs3790426, rs10493380) and haplotype A-A-A-A in block 4 in the inland data (rs1782754, rs1022981, rs6673324, rs1137100) were nominally associated with WC, P=7.085 × 10(-22) (adjusted P=0.0979) and P=5.496 × 10(-144) (adjusted P=0.1062), respectively. PMID:25296580

  16. Novel locus for fibrinogen in 3' region of LEPR gene in island population of Vis (Croatia).

    PubMed

    Tomas, Željka; Petranović, Matea Zajc; Škarić-Jurić, Tatjana; Barešić, Ana; Salihović, Marijana Peričić; Narančić, Nina Smolej

    2014-11-01

    Leptin, a possible mediator between energy homeostasis, inflammation and cardiovascular disease (CVD), acts via leptin receptors. We investigated association of single-nucleotide polymorphisms (SNPs) and haplotypes of the leptin receptor gene (LEPR) with several CVD risk factors: body mass index, waist circumference (WC), serum lipids, fibrinogen and C-reactive protein levels. Thirty-one SNPs in and near LEPR gene were analyzed in 986 inhabitants of the island of Vis, Croatia and 29 SNPs in the inland sample (N=499). We assessed linkage disequilibrium (LD), SNP and haplotype associations with the selected phenotypes. rs4291477 significantly associated with fibrinogen (P=0.003) and rs7539471 marginally significantly with high-density lipoprotein (P=0.004), but only in the Vis sample, while rs10493384 marginally significantly associated with triglyceride levels (P=0.006) in the inland sample. SNPs were grouped into eight LD blocks in Vis and in seven blocks in the inland population. Haplotype A-C-A-A-G-A in block 5 in Vis (rs1782754, rs1171269, rs1022981, rs6673324, rs3790426, rs10493380) and haplotype A-A-A-A in block 4 in the inland data (rs1782754, rs1022981, rs6673324, rs1137100) were nominally associated with WC, P=7.085 × 10(-22) (adjusted P=0.0979) and P=5.496 × 10(-144) (adjusted P=0.1062), respectively.

  17. Transient Decrease in Circulatory Testosterone and Homocysteine Precedes the Development of Metabolic Syndrome Features in Fructose-Fed Sprague Dawley Rats

    PubMed Central

    Sakamuri, Anil; Pitla, Sujatha; Putcha, Uday Kumar; Jayapal, Sugeedha; Pothana, Sailaja; Vadakattu, Sai Santosh

    2016-01-01

    Background. Increased fructose consumption is linked to the development of metabolic syndrome (MS). Here we investigated the time course of development of MS features in high-fructose-fed Sprague Dawley rats along with circulatory testosterone and homocysteine levels. Methods. Rats were divided into control and experimental groups and fed with diets containing 54.5% starch and fructose, respectively, for 4, 12, and 24 weeks. Plasma testosterone and homocysteine levels were measured along with insulin, glucose, and lipids. Body composition, insulin resistance, and hepatic lipids were measured. Results. Increase in hepatic triglyceride content was first observed in metabolic disturbance followed by hypertriglyceridemia and systemic insulin resistance in fructose-fed rats. Hepatic lipids were increased in time-dependent manner by fructose-feeding starting from 4 weeks, but circulatory triglyceride levels were increased after 12 weeks. Fasting insulin and Homeostatis Model Assessment of Insulin Resistance (HOMA-IR) were increased after 12 weeks of fructose-feeding. Decreased visceral adiposity, circulatory testosterone, and homocysteine levels were observed after 4 weeks of fructose-feeding, which were normalized at 12 and 24 weeks. Conclusions. We conclude that transient decrease in circulatory testosterone and homocysteine levels and increased hepatic triglyceride content are the earliest metabolic disturbances that preceded hypertriglyceridemia and insulin resistance in fructose-fed SD rats.

  18. FbsA-Driven Fibrinogen Polymerization: A Bacterial ``Deceiving Strategy''

    NASA Astrophysics Data System (ADS)

    Pierno, Matteo; Maravigna, Laura; Piazza, Roberto; Visai, Livia; Speziale, Pietro

    2006-01-01

    We show that FbsA, a cell wall protein of the bacterium Streptococcus agalactiae, promotes large-scale aggregation of human plasma fibrinogen, leading to the formation of a semiflexible polymerlike network. This extensive aggregation process takes place not only in solution, but also on FbsA-functionalized colloidal particles, and leads to the formation of a thick layer on the bacterial cell wall itself, which becomes an efficient mask against phagocytosis.

  19. Surface characterization and AFM imaging of mixed fibrinogen-surfactant films.

    PubMed

    Hassan, Natalia; Maldonado-Valderrama, Julia; Gunning, A Patrick; Morris, Victor J; Ruso, Juan M

    2011-05-19

    This study describes the adsorption behavior of mixed protein/surfactant systems at the air-water interface: specifically fibrinogen and the fluorinated and hydrogenated surfactants (C(8)FONa, C(8)HONa, and C(12)HONa). Surface tension techniques and atomic force microscopy (AFM) have been combined to investigate the adsorption behavior of these mixed systems. Interfacial rheology showed that fibrinogen has a low dilatational modulus at the air-water interface when compared to other proteins, suggesting the formation of a weak surface network. Fluorinated and hydrogenated surfactants severely decreased the dilatational modulus of the adsorbed fibrinogen film at the air-water interface. These measurements suggest the progressive displacement of fibrinogen from the air-water interface by both types of surfactants. However, in the case of fibrinogen/fluorinated surfactant systems, surface tension and dilatational rheology measurements suggest the formation of complexes with improved surface activity. AFM imaging of fibrinogen in the presence and absence of surfactants provided new information on the structure of mixed surface films, and revealed new features of the interaction of fibrinogen with hydrogenated and fluorinated surfactants. These studies suggest complexes formed between fibrinogen and fluorinated surfactants which are more surface active than fibrinogen, while the absence of interaction between fibrinogen and hydrogenated surfactants (C(8)HONa and C(12)HONa) results in compaction of the surface layer.

  20. Prognostic Impact of Pretreatment Plasma Fibrinogen in Patients with Locally Advanced Oral and Oropharyngeal Cancer

    PubMed Central

    Holzinger, Daniel; Danilovic, Ivan; Seemann, Rudolf; Kornek, Gabriela; Engelmann, Johannes; Pillerstorff, Robert; Holawe, Simone; Psyrri, Amanda; Erovic, Boban M.; Farwell, Gregory; Perisanidis, Christos

    2016-01-01

    Background We aimed to determine the prognostic significance of pretreatment plasma fibrinigen in patients with oral and oropharyngeal squamous cell carcinoma (OOSCC). Methods A cohort of 183 patients with locally advanced OOSCC receiving preoperative chemoradiotherapy was retrospectively examined. Using ROC curve analysis, a pretreatment plasma fibrinogen cutoff value of 447mg/dL was determined. The primary endpoints were overall survival and recurrence-free survival. A secondary endpoint was to determine whether pretreatment plasma fibrinogen could predict treatment response to neoadjuvant chemoradiotherapy. Cox regression models and Kaplan–Meier curves were used for survival analyses. Results Seventy-one patients had an elevated pretreatment plasma fibrinogen (fibrinogen >447mg/dL). Patients with high fibrinogen showed significantly higher pathologic stages after neoadjuvant treatment than those with low fibrinogen (p = 0.037). In univariate analysis, elevated fibrinogen was associated with poor overall survival (p = 0.005) and recurrence-free survival (p = 0.008) Multivariate analysis revealed that elevated fibrinogen remained an independent risk factor for death (hazard ratio 1.78, 95% CI 1.09–2.90, p = 0.021) and relapse (hazard ratio 1.78, 95% CI 1.11–2.86, p = 0.016). Conclusion Elevated pretreatment plasma fibrinogen is associated with lack of response to neoadjuvant chemoradiotherapy and reduced OS and RFS in patients with OOSCC. Thus, plasma fibrinogen may emerge as a novel prognostic indicator and a potential therapeutic target in OOSCC. PMID:27362659

  1. Cross-linking of fibrinogen and fibrin by fibrin-stablizing factor (factor XIIIa).

    PubMed

    Kanaide, H; Shainoff, J R

    1975-04-01

    Factor XIIIa catalyzed intermolecular cross-linking of fibrinogen at initial rates that varied in direct (first order) proportion to the fibrinogen concentration, which differed from the well known zero order relationship in fibrin cross-linking. Preferential cross-linking of gamma-chains occurred with both substrates. The differences in rates and order of reaction were attributed mainly to effect of self-alignment of the gamma-chains in fibrin which enabled the cross-linking enzyme to interact with paired chains as a single rather than two independent entities. Studies on mixtures of fibrinogen and fibrin indicated factor XIIIa had near equal affinities for the two substrates. At low concentrations with which cross-linking of fibrinogen proceeded sluggishly compared to fibrin, fibrinogen inhibited stabilization of fibrin clots by competitively partitioning factor XIIIa away from the fribin. Additional inhibition arose from cross-linking of fibrin in soluble combination with fibrinogen in mixtures containing fibrinogen in large excess over fibrin. The observations demonstrate ways in which fibrinogen normally helps to suppress both polymerization and cross-linking of small amounts of fibrin produced within the circulation. At very high concentrations above 30 mg. per milliliter, fibrinogen underwent cross-linking at faster initial rates than the cross-linking of fibrin. Rapid cross-linking of concentrated fibrogen raises the possibility that filtration enrichment may be a factor contributing to abnormal formation of the highly insoluble fibrinogen deposits occurring in atheromatous tissue.

  2. Zn2+ Mediates High Affinity Binding of Heparin to the αC Domain of Fibrinogen*

    PubMed Central

    Fredenburgh, James C.; Leslie, Beverly A.; Stafford, Alan R.; Lim, Teresa; Chan, Howard H.; Weitz, Jeffrey I.

    2013-01-01

    The nonspecific binding of heparin to plasma proteins compromises its anticoagulant activity by reducing the amount of heparin available to bind antithrombin. In addition, interaction of heparin with fibrin promotes formation of a ternary heparin-thrombin-fibrin complex that protects fibrin-bound thrombin from inhibition by the heparin-antithrombin complex. Previous studies have shown that heparin binds the E domain of fibrinogen. The current investigation examines the role of Zn2+ in this interaction because Zn2+ is released locally by platelets and both heparin and fibrinogen bind the cation, resulting in greater protection from inhibition by antithrombin. Zn2+ promotes heparin binding to fibrinogen, as determined by chromatography, fluorescence, and surface plasmon resonance. Compared with intact fibrinogen, there is reduced heparin binding to fragment X, a clottable plasmin degradation product of fibrinogen. A monoclonal antibody directed against a portion of the fibrinogen αC domain removed by plasmin attenuates binding of heparin to fibrinogen and a peptide analog of this region binds heparin in a Zn2+-dependent fashion. These results indicate that the αC domain of fibrinogen harbors a Zn2+-dependent heparin binding site. As a consequence, heparin-catalyzed inhibition of factor Xa by antithrombin is compromised by fibrinogen to a greater extent when Zn2+ is present. These results reveal the mechanism by which Zn2+ augments the capacity of fibrinogen to impair the anticoagulant activity of heparin. PMID:23990470

  3. Fibrinogen Degradation Products and Periodontitis: Deciphering the Connection

    PubMed Central

    2015-01-01

    Introduction Fibrinogen degradation products (e.g. D-dimer) arise from digested fibrin clots and fibrinogen. Elevated concentrations accompany activation of coagulation and fibrinolysis and indicate chronic inflammatory diseases. D-Dimer tests are a quick, noninvasive method to rule out abnormal clotting. Periodontitis strongly affects the haemostatic system and evokes a procoagulant state. Correlation of chronic periodontitis with early indicators of disease (biomarkers) might be useful. Aim The aim of the study was to examine whether the plasma D-dimer concentration reflects the progression of chronic periodontitis and the beneficial effect of periodontal therapy. Materials and Methods Forty randomly selected subjects were divided into four groups, Group I: 10 healthy subjects, Group II: 10 with mild periodontitis, Group III: 10 with moderate periodontitis, Group IV: 10 with severe periodontitis. After thorough dental and periodontal examination, 3 mL of venous blood was collected for measurement of fibrinogen degradation products. Results The patients with moderate and chronic periodontitis exhibited high concentrations of D-dimer (mean value 434.98–535.52 mcg/mL), whereas subjects with mild or no periodontitis exhibited values of 329.78–211.29 mcg/mL. Concentrations of D-dimer were significantly reduced after therapy of all classes of periodontitis. Conclusion Periodontal treatment can reduce amount of D-dimer in the plasma. A higher than normal concentration is observed in chronic periodontitis. PMID:26816985

  4. The reduced soluble fibrinogen-like protein 2 and regulatory T cells in acute coronary syndrome

    PubMed Central

    Liu, Kun; Li, Ting; Huang, Shiyuan; Long, Rui; You, Ya; Liu, Jinping

    2016-01-01

    Soluble fibrinogen-like protein 2, sfgl2, is the new effector of CD4+CD25+FOXP3+ regulatory T cell (Treg) and exerts immunosuppressive activity. We design this study to investigate the possible role of sfgl2 in atherosclerosis. A total of 58 acute coronary syndrome (ACS) patients, together with 22 stable angina (SA) patients and 31 normal coronary artery (NCA) people were enrolled in our study. Serum level of sfgl2 and plasma level of Treg were respectively measured. In line with the change of Treg, serum level of sfgl2 in ACS (8.70 ng/mL) was significantly decreased (P = 0.003), compared with that in SA (11.86 ng/mL) and NCA (17.55 ng/mL). Both sfgl2 and Treg level were obviously decreased in ACS; Sfgl2 may play a protective role in atherosclerosis. PMID:26515143

  5. Alpha-methyl-homocysteine thiolactone protects lung of BALB/c mice irradiated with 6 Gy

    NASA Astrophysics Data System (ADS)

    Lubec, G.; Foltinova, J.; Leplawy, T.; Mallinger, R.; Tichatschek, E.; Getoff, N.

    1996-06-01

    The radiation protective activity of intraperitoneally administered alpha-methyl-homocysteine thiolactone (α-MHCTL; 100 mg/kg body weight) in female BALB/c mice and such treated with cysteine treated (100 mg/kg body weight), using unirradiated and placebo treated irradiated mice were tested as controls. 6 Gy whole body irradiated was applied and after a period of three weeks the animals were sacrificed and lungs were taken for morphometry and the determination of o-tyrosine. Septal areas were highest in the irradiated, placebo treated mice (68.67 + 9.82% septal area to total area)and lowest in the α-MHCTL treated irradiated mice (55.67 +11.29%), significant at the p < 0.05 level. Morphometric data were accompanied by highest levels of o-tyrosine, a reliable parameter for OH-attack, in the irradiated, placebo treated group with 1.87 + 0.40 μM/g lung tissue and 0.32 + 0.13 gmM/g lung tissue in the αMHCTL treated group; the statistical difference was significant. Significant radiation protection in the mammalian system at the morphological and biochemical level were found. The potent effect could be explained by the influence of alpha-alkylation in homocysteine thiolactone (HCTL) which renders amino acids unmetabolizeable, nontoxic, increases lipophilicity and therefore improving permeability through membranes. The present report confirms morphological data on the radiation protective activity of this interesting thiol compound.

  6. AB156. Homocysteine and vitamin B12: risk factors for erectile dysfunction

    PubMed Central

    Lu, Zheng; Mo, Zengnan

    2014-01-01

    Background Increasing levels of homocysteine (Hcy) is associated with cardiovascular disease, and erectile dysfunction (ED) has close relation with cardiovascular disease, therefore, high homocysteine may be one of the risk factors of ED. During the metabolism of homocysteine, vitamin B12 plays an important role and could be the main factor in causing erectile dysfunction as well. Purpose To investigate the relationship between Hcy, vitamin B12 and ED in sample. Methods The study included 1,457 men aged 20-69 who participated in a series of physical examination at the Medical Centre in Fangchenggang First People’s Hospital from September 2009 to December 2009. ED was identified by the five-item International Index of Erectile Function (IIEF-5) questionnaire. All participants were measured for plasma Hcy, vitamin B12, folic acid, systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), fasting plasma glucose, triglyceride and high-density lipoprotein cholesterol (HDL). Smoking, alcoholic drinking and physical activity were collected by face to face communication. Results A total of 691 (47.4%) men were identified as ED in this study, participants with ED were older or more likely to drink alcohol than the non-ED. It was higher Hcy (P=0.032), vitamin B12 (P=0.008) and fasting plasma glucose (P=0.014) in the participants with ED. There were significant positive correlation between ED status (none, mile, moderate and severe) and Hcy (P=0.024), vitamin B12 (P=0.015) and fasting plasma glucose (P=0.002). Logistic regression analysis showed that age, Hcy and vitamin B12 were the main determinants in ED. Hcy was positively associated with ED in the men more than 45, but vitamin B12 was positively related with ED in the men less than 45. Conclusions Hcy was positively associated with ED in elder, however, vitamin B12 was positively related with ED in younger.

  7. A comparison of the effects of cheese and butter on serum lipids, haemostatic variables and homocysteine.

    PubMed

    Biong, Anne S; Müller, Hanne; Seljeflot, Ingebjørg; Veierød, Marit B; Pedersen, Jan I

    2004-11-01

    Milk fat contains considerable amounts of saturated fatty acids, known to increase serum cholesterol. Little is known, however, about the relative effect of different milk products on risk factors for CHD. The aim of the present study was to compare the effects of Jarlsberg cheese (a Norwegian variety of Swiss cheese) with butter on serum lipoproteins, haemostatic variables and homocysteine. A controlled dietary study was performed with twenty-two test individuals (nine men and thirteen women) aged 23-54 years. The subjects consumed three isoenergetic test diets, with equal amounts of fat and protein, and containing either cheese (CH diet), butter + calcium caseinate (BC diet) or butter + egg-white protein (BE diet). The study was a randomised cross-over study and the subjects consumed each diet for 3 weeks, with 1 week when they consumed their habitual diet in between. Fasting blood samples were drawn at baseline and at the end of each period. Serum was analysed for lipids and plasma for haemostatic variables and homocysteine. Total cholesterol was significantly lower after the CH diet than after the BC diet (-0.27 mmol/l; P=0.03), while the difference in LDL-cholesterol was found to be below significance level (-0.22 mmol/l; P=0.06). There were no significant differences in HDL-cholesterol, triacylglycerols, apo A-I, apo B or lipoprotein (a), haemostatic variables and homocysteine between the diets. The results indicate that, at equal fat content, cheese may be less cholesterol increasing than butter.

  8. [Prognostic value of serum homocysteine levels in elderly hospitalized patients].

    PubMed

    Hernández-Betancor, Iván; Martín-Ponce, Esther; Martínez-Riera, Antonio; Viña-Rodríguez, Juan José; González-Reimers, Emilio; de la Vega-Prieto, María José; Santolaria, Francisco

    2015-06-01

    Antecedentes y objetivos: el aumento de la homocisteína se relaciona con la enfermedad vascular y un incremento de la mortalidad. La disminución de la homocisteína se asocia también con un peor pronóstico en enfermos en hemodiálisis; sin embargo, esta relación no ha sido bien estudiada en otro tipo de pacientes. El objetivo del estudio fue analizar el valor pronóstico de los niveles de homocisteína en enfermos ancianos pluripatológicos ingresados en un servicio general de medicina interna Pacientes y métodos: estudiamos a 239 pacientes (121 mujeres y 118 varones; edad media: 78 años) en los que determinamos la homocisteína sérica y la relacionamos con los factores de riesgo vascular, enfermedad vascular: cardiopatía isquémica, ACV isquémico y arteriopatía periférica, estado de nutrición, creatinina, albúmina, ácido fólico y vitamina B12. Resultados: la mortalidad durante el ingreso de los enfermos con homocisteína menor de 9 mol/l fue del 33%, del 9% cuando estaba entre 9 y 20 mol/l y del 17% si era superior a 20 mol/l. La disminución de la homocisteína se relacionó con mayor comorbilidad, pérdida de peso y disminución de la albúmina. A largo plazo, el aumento de la homocisteína se relacionó con mayor mortalidad, especialmente en los pacientes con enfermedad vascular. Conclusión: en los pacientes ancianos pluripatológicos tanto la disminución como el aumento de la homocisteína se asocian con una mayor mortalidad.

  9. S-Adenosylmethionine and S-adenosylhomocystein metabolism in isolated rat liver. Effects of L-methionine, L-homocystein, and adenosine.

    PubMed

    Hoffman, D R; Marion, D W; Cornatzer, W E; Duerre, J A

    1980-11-25

    The effects of varying concentrations of L-methionine, L-homocysteine, and adenosine on the tissue levels of S-adenosylmethionine (AdoMet) and S-adenosyl-homocystein (AdoHcy) were investigated in perfused liver. In the normal liver, the intracellular concentration of AdoMet was dependent upon the availability of methionine. In the presence of high concentrations of methionine the maximum level of AdoMet attainable was 300 nmol/g of liver. The exogenous concentration of methionine did not alter the hepatic concentration of AdoHcy (8 to 20 nmol/g) while adenosine or homocysteine blocked hydrolysis of AdoHcy resulting in elevated levels of AdoHcy (400 to 600 nmol/g) and AdoMet (300 to 600 nmol/g). The addition of both adenosine (4mM) and homocysteine (3.4 mM) to the perfusate further increased the levels of AdoHcy (4 mumol/g) and AdoMet (1.2 mumol/g). As the concentration of AdoHcy increased, significant amounts of this compound were released into the perfusate, while AdoMet was not detected. Under all conditions where AdoHcy accumulated in the cell, a concomitant increase in the AdoMet level occurred. Apparently AdoHcy acts as a positive effector of the S-adenosylmethionine synthase. The hepatocytes did not take up significant amounts of [methyl-14C]AdoMet from the perfusate nor were any [14C]methyl groups from this compound incorporated into histones, DNA, or phospholipids. In contrast, [14C]methyl groups were readily incorporated into these macromolecules from exogenous [methyl-14C]methionine. The addition of adenosine (4 mM) and homocystein (3.4 mM) shifted the AdoMet:AdoHcy ratio from 8.2 to 0.3. Under these conditions, transmethylation was inhibited markedly.

  10. Plasma Fibrinogen in Type 2 Diabetic Patients with Metabolic Syndrome and its Relation with Ischemic Heart Disease (IHD) and Retinopathy

    PubMed Central

    Mahendra, J.V.; Anuradha, T.S.; Talikoti, Prashanth; Nagaraj, R.S.; Vishali, V.

    2015-01-01

    Introduction: Metabolic syndrome or Syndrome X is characterized by hyperlipidemia, increased blood pressure, abdominal obesity and hyperglycemia, which increases the risk of cardiovascular complications. In addition to these, it is also associated with nontraditional risk factor like C- reactive protein, Plasminogen activator and fibrinogen. Various studies have documented association of these nontraditional risk factor, in Type 2 diabetes mellitus. Thus patients with diabetes mellitus are higher risk of developing micro and macro vascular complications like ischemic heart disease (IHD) and diabetic retinopathy. Diabetic retinopathy is the leading cause of decreased visual acuity, which is associated with maculopathy and profierative complications of it. Chronic hyperglycemia and its associated nonenzymatic glycation play an important role in the development of microangiopathy. Aims and Objectives: To study the prevalence of the metabolic syndrome in type 2 diabetes mellitus. To study the plasma fibrinogen and its relationship with IHD and retinopathy in type 2 Diabetes mellitus patients with metabolic syndrome. Materials and Methods: Patients of type 2 diabetes Mellitus were recruited based on the inclusion and exclusion criteria. History of IHD and ECG evidence of ischemia was obtained. Retinopathy was diagnosed by direct opthalmoscopy. Fasting glucose, lipid profile and plasma fibrinogen were analyzed. Stastical analysis was carried by Chi square test and student‘t’ test. Results: The prevalence of metabolic syndrome in study population of 100 type 2 diabetic patients is 58% and is significantly associated with duration of the disease (p<0.001). Fifty eight patients have hyperfibrinogenemia and mean fibrinogen level is significantly high in diabetic patients with metabolic syndrome when compared to diabetic patients without metabolic syndrome (p<0.001). Diabetic patient with metabolic syndrome and hyperfibrinogenemia have higher prevalence of IHD and

  11. The effect of fibrin(ogen) on thrombin generation and decay.

    PubMed

    Kremers, R M W; Wagenvoord, R J; Hemker, H C

    2014-09-01

    Defibrination causes a ~30% decrease of thrombin generation (TG) which can be restored by adding native fibrinogen in its original concentration (3 mg/ml). The fibrinogen variant γA/γ', which binds thrombin with high affinity, is over four times more efficient in this respect than the more common γA/γA form. By using high tissue factor concentrations we accelerated prothrombin conversion so as to obtain a descending part of the TG curve that was governed by thrombin decay only. From that part we calculated the antithrombin (AT)- and α2-macroglobulin-dependent decay constants at a series of concentrations of native, γA/γA and γA/γ' fibrinogen. We found that the increase of TG in the presence of fibrinogen is primarily due to a dose-dependent decrease of thrombin inactivation by α2-macroglobulin, where the γA/γ' form is much more active than the γA/γA form. AT-dependent decay is somewhat decreased by γA/γ' fibrinogen but hardly by the γA/γA form. We assume that binding of thrombin to fibrin(ogen) interferes with its binding to inhibitors. Attenuation of decay only in part explains the stimulating effect of fibrinogen on TG, as fibrinogen stimulates prothrombin conversion, regardless of the fibrinogen variant.

  12. Influence of 5,10-methylenetetrahydrofolate reductase gene polymorphism on plasma homocysteine concentration in patients with end-stage renal disease.

    PubMed

    Lee, H A; Choi, J S; Ha, K S; Yang, D H; Chang, S K; Hong, S Y

    1999-08-01

    The purpose of this study is to observe the influence of the methylenetetrahydrofolate reductase (MTHFR) gene (677C-->T substitution) on plasma homocysteine levels in end-stage renal disease (ESRD) patients who received a relatively large amount of folate (2 mg/d) and are undergoing hemodialysis. A cross-sectional study of plasma homocysteine, vitamin B(12), and folate was performed in patients with ESRD. The study population for the MTHFR gene study included 312 healthy subjects and 106 patients with ESRD undergoing hemodialysis. The C677T transition in the MTHFR gene was detected by HinF 1 restriction enzyme analysis and subsequent electrophoresis in a 3% agarose gel. The genotype of the MTHFR gene in 106 patients with ESRD was homozygous C677T mutation (VV) in 17 patients (16.1%) and heterozygous (AV) in 63 patients (58.4%); 26 patients (24.5%) did not carry this mutation (AA). The mean levels of homocysteine, vitamin B(12), and folate in the patients with ESRD were 23.3 +/- 14.0 mmol/L, 620.2 +/- 98.5 pmol/L, and 138.6 +/- 55.6 nmol/L, respectively. There was no significant difference in homocysteine levels among the three genotypes: 28.2 +/- 19.4 mmol/L for VV, 22.7 +/- 14.9 mmol/L for AV, and 23.4 +/- 11.1 mmol/L for AA genotype (P > 0.05). There was no difference in genotype distribution between the patient groups of less than 25th and greater than 75th percentiles, classified according to plasma homocysteine levels (P = 0.47). In conclusion, with high-dose folate supplementation, the hyperhomocysteinemia in patients with ESRD does not seem to be caused by the 677C-->T mutation in the MTHFR gene. PMID:10430972

  13. The influence of residual water on the solid-state properties of freeze-dried fibrinogen.

    PubMed

    Wahl, Verena; Leitgeb, Stefan; Laggner, Peter; Pichler, Harald; Liebminger, Andreas; Khinast, Johannes

    2015-04-01

    The purpose of this work was to investigate the influence of residual water in freeze-dried protein powders on the dissolution behavior of the solid-state proteins. To that end, six freeze-dried fibrinogen powder lots were stored at four levels of relative humidity and analyzed with regard to the particle size and shape, the specific surface area, the solid state of protein and the inner surface. Furthermore, the dissolution behavior of the powders was investigated. We clearly identified differences in the specific surface area, specific inner surface area, crystallinity, particle size and shape, which we were able to correlate to the dissolution behavior. These differences were triggered due to the different levels of residual moisture during two weeks of storage. Thus, we were able to show that the storage conditions have significant impact on the processing of pharmaceutical protein materials.

  14. Effect modification by population dietary folate on the association between MTHFR genotype, homocysteine, and stroke risk: a meta-analysis of genetic studies and randomised trials

    PubMed Central

    Holmes, Michael V; Newcombe, Paul; Hubacek, Jaroslav A; Sofat, Reecha; Ricketts, Sally L; Cooper, Jackie; Breteler, Monique MB; Bautista, Leonelo E; Sharma, Pankaj; Whittaker, John C; Smeeth, Liam; Fowkes, F Gerald R; Algra, Ale; Shmeleva, Veronika; Szolnoki, Zoltan; Roest, Mark; Linnebank, Michael; Zacho, Jeppe; Nalls, Michael A; Singleton, Andrew B; Ferrucci, Luigi; Hardy, John; Worrall, Bradford B; Rich, Stephen S; Matarin, Mar; Norman, Paul E; Flicker, Leon; Almeida, Osvaldo P; van Bockxmeer, Frank M; Shimokata, Hiroshi; Khaw, Kay-Tee; Wareham, Nicholas J; Bobak, Martin; Sterne, Jonathan AC; Smith, George Davey; Talmud, Philippa J; van Duijn, Cornelia; Humphries, Steve E; Price, Jackie F; Ebrahim, Shah; Lawlor, Debbie A; Hankey, Graeme J; Meschia, James F; Sandhu, Manjinder S; Hingorani, Aroon D; Casas, Juan P

    2011-01-01

    folate status (predicted RR 1·00, 95% CI 0·90 to 1·11). Although the predicted effect of homocysteine reduction from large genetic studies in low folate regions (Asia) was larger (RR 0·78, 95% CI 0·68 to 0·90), no trial has evaluated the effect of lowering of homocysteine on stroke risk exclusively in a low folate region. Interpretation In regions with increasing levels or established policies of population folate supplementation, evidence from genetic studies and randomised trials is concordant in suggesting an absence of benefit from lowering of homocysteine for prevention of stroke. Further large-scale genetic studies of the association between MTHFR 677C→T and stroke in low folate settings are needed to distinguish effect modification by folate from small-study bias. If future randomised trials of homocysteine-lowering interventions for stroke prevention are undertaken, they should take place in regions with low folate consumption. Funding Full funding sources listed at end of paper (see Acknowledgments). PMID:21803414

  15. Combined single cell AFM manipulation and TIRFM for probing the molecular stability of multilayer fibrinogen matrices

    PubMed Central

    Christenson, W.; Yermolenko, I.; Plochberger, B.; Camacho-Alanis, F.; Ros, A.; Ugarova, T.P.; Ros, R.

    2014-01-01

    Adsorption of fibrinogen on various surfaces produces a nanoscale multilayer matrix, which strongly reduces the adhesion of platelets and leukocytes with implications for hemostasis and blood compatibility of biomaterials. The nonadhesive properties of fibrinogen matrices are based on their extensibility, ensuing the inability to transduce strong mechanical forces via cellular integrins and resulting in weak intracellular signaling. In addition, reduced cell adhesion may arise from the weaker associations between fibrinogen molecules in the superficial layers of the matrix. Such reduced stability would allow integrins to pull fibrinogen molecules out of the matrix with comparable or smaller forces than required to break integrin–fibrinogen bonds. To examine this possibility, we developed a method based on the combination of total internal reflection fluorescence microscopy, single cell manipulation with an atomic force microscope and microcontact printing to study the transfer of fibrinogen molecules out of a matrix onto cells. We calculated the average fluorescence intensities per pixel for wild-type HEK 293 (HEK WT) and HEK 293 cells expressing leukocyte integrin Mac-1 (HEK Mac-1) before and after contact with multilayered matrices of fluorescently labeled fibrinogen. For contact times of 500 s, HEK Mac-1 cells show a median increase of 57% of the fluorescence intensity compared to 6% for HEKWT cells. The results suggest that the integrin Mac-1-fibrinogen interactions are stronger than the intermolecular fibrinogen interactions in the superficial layer of the matrix. The low mechanical stability of the multilayer fibrinogen surface may contribute to the reduced cell adhesive properties of fibrinogen-coated substrates. We anticipate that the described method can be applied to various cell types to examine their integrin-mediated adhesion to the extracellular matrices with a variable protein composition. PMID:24239757

  16. [Some aspects of homocysteine metabolism in hemodialysis patients].

    PubMed

    Bednarek-Skublewska, Anna; Buraczyńska, Monika; Wawrzycki, Sławomir; Baranowicz-Gaszczyk, Iwona; Ksiazek, Andrzej

    2002-11-01

    Homocysteine (Hcy) is a non-protein forming sulfur amino acid, synthesised from methionine (Met), whose metabolism is at the junction of two metabolic pathways: remethylation and transsulfuration. Increased Hcy serum concentration is a well established independent risk factor of cardiovascular diseases and a known feature of end stage renal disease. Hcy plasma level is influenced by folate, vitamin B6 and genetic factors. Mutation C677T in gene encoding methylenetetrahydrofolate reductase (MTHFR), an enzyme involved in Hcy remethylation has been associated with elevated Hcy in homozygous carriers (TT genotype). Several amino acids take part in metabolism of Hcy. There are abnormalities of concentration of the non essential and essential of amino acids in serum of patients treated with hemodialysis (HD). It is possible that these abnormalities of amino acids can change the Hcy metabolism. The aim of this study was the evaluation of some aspects of Hcy metabolism. We examined the MTHFR gene polymorphism and its relationship with plasma Hcy concentration. The plasma levels of total amino acids and amino acids connected with Hcy metabolism: methionine (Met), seryne (Ser), cysteine (Cyst) and tauryne (Tau) were evaluated in hemodialysis patients. The study was conducted in 71 (35 male, 36 female) patients, mean age 56.2 +/- 12.4 years. They were dialysed for a mean duration of 87.7 +/- 84.7 months (range 2-302). The control group (CG) in which Hcy and amino acids levels were examined consisted of 12 healthy subjects. Serum (EDTA) Hcy levels were measured by EIA-Hcy ELISA kit. The MTHFR gene polymorphism was evaluated by means of the polymerase chain reaction (PCR). The amino acids were measured by chromatography in amino acid analyser AAA 400. Mean concentration of Hcy was significantly higher in patients than in CG (31.1 +/- 9.1 vs 11.9 +/- 2.9 mumol/L; p < 0.01). Genotype frequencies in patients were: 42.8% for CC, 48.5% for CT and 8.7% for TT. Mean concentration of

  17. Enhanced bacterial adhesion on surfaces pretreated with fibrinogen and fibronectin

    SciTech Connect

    Mohammad, S.F.; Topham, N.S.; Burns, G.L.; Olsen, D.B.

    1988-07-01

    The effect of certain plasma proteins on the adhesion of Pseudomonas aeruginosa and Staphylococcus epidermidis on polyurethane, polyvinylchloride, or glass was investigated. Test surfaces were treated with serum, plasma, albumin, immunoglobulin G, fibrinogen, or fibronectin. Using a specially designed test chamber, surfaces previously treated with test proteins were incubated with bacterial suspension. During the experiment, the test chamber was placed on a rotator to prevent settling of bacteria. At the end of the experiment, each test well was rinsed repeatedly to remove non-adherent bacteria. The number of bacteria adherent to the test surfaces was quantitated by a combination of methods including microscopic counting of cells, scintillation counting and autoradiography. It was noted that a greater number of bacteria adhered to surfaces coated with fibrinogen or fibronectin whereas surfaces treated with serum showed reduced bacterial adhesion. The inhibitory effect of serum appeared more pronounced with S. epidermidis when compared with P. aeruginosa under identical experimental conditions. Scanning electron microscopy revealed that adherent bacteria were randomly distributed on the test surfaces and appeared to replicate while still adherent. These observations suggested that bacterial adhesion to biomaterials can be significantly influenced by the composition of the adsorbed proteins at the interface.

  18. Conversion from cognitive health to mild cognitive impairment and Alzheimer's disease: prediction by plasma amyloid beta 42, medial temporal lobe atrophy and homocysteine.

    PubMed

    Blasko, Imrich; Jellinger, Kurt; Kemmler, Georg; Krampla, Wolfgang; Jungwirth, Susanne; Wichart, Ildigo; Tragl, Karl Heinz; Fischer, Peter

    2008-01-01

    The changes of plasma amyloid beta (Abeta42) protein, homocysteine and medial temporal lobe atrophy (MTA) were studied by the transition from cognitive health to mild cognitive impairment (MCI) and to Alzheimer's disease (AD) in a prospective cohort of individuals aged 75 years. MTA but not plasma Abeta42 measured at baseline predicted which persons remained cognitively healthy (CH) and who developed AD 2.5 years later. The increase of plasma Abeta42 over time significantly distinguished between persons who remained CH on the one hand and MCI converters and AD converters out of cognitive health on the other (CH-to-MCI and CH-to-AD converters). Although both groups showed similar increase of Abeta42 levels, CH-to-AD converters had a higher increase of homocysteine compared to CH-to-MCI converters or to persons remaining CH. In comparison to all cognitive subgroups, the AD converters from MCI at baseline showed the smallest increase of Abeta42 levels and rather no increase of homocysteine. In logistic regression analysis, the increase of plasma Abeta42 but not change of MTA significantly predicted the conversion from CH to MCI, and changes of MTA and homocysteine but not of plasma Abeta42 predicted the conversion from CH to AD. The increase of plasma Abeta42 correctly allocated CH-to-MCI and CH-to-AD converters with low (63%) specificity (for both) and low (60%) sensitivity (54% for AD group). These results indicate that (1) plasma Abeta42 alone is not suitable as a biomarker for AD, (2) in the course of cognitive deterioration of the AD-type the increase of plasma Abeta42 seems to be an initial event, (3) similar to cerebrospinal fluid, changes of plasma Abeta42 may reflect the transition from cognitive health to AD, and (4) whether persons with MCI develop AD may depend on an accumulation of further toxic metabolites such as homocysteine.

  19. Homocysteine-Lowering and Cardiovascular Disease Outcomes in Kidney Transplant Recipients: Primary Results from the Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) Trial

    PubMed Central

    Bostom, Andrew G.; Carpenter, Myra A.; Kusek, John W.; Levey, Andrew S.; Hunsicker, Lawrence; Pfeffer, Marc A.; Selhub, Jacob; Jacques, Paul F.; Cole, Edward; Gravens-Mueller, Lisa; House, Andrew A.; Kew, Clifton; McKenney, Joyce L.; Pacheco-Silva, Alvaro; Pesavento, Todd; Pirsch, John; Smith, Stephen; Solomon, Scott; Weir, Matthew

    2015-01-01

    Background Kidney transplant recipients, like other patients with chronic kidney disease (CKD), experience excess risk of cardiovascular disease (CVD) and elevated total homocysteine (tHcy) concentrations. Observational studies of patients with CKD suggest increased homocysteine is a risk factor for CVD. The impact of lowering total homocysteine (tHcy) levels in kidney transplant recipients is unknown. Methods and Results In a double-blind controlled trial, we randomized 4110 stable kidney transplant recipients to a multivitamin that included either a high dose (n=2056) or low dose (n=2054) of folic acid, vitamin B6, and vitamin B12 to determine whether decreasing tHcy concentrations reduced the rate of the primary composite arteriosclerotic CVD outcome (myocardial infarction, stroke, CVD death, resuscitated sudden death, coronary artery or renal artery revascularization, lower extremity arterial disease, carotid endarterectomy or angioplasty, or abdominal aortic aneurysm repair). Mean follow-up was 4.0 years. Treatment with the high dose multivitamin reduced homocysteine but did not reduce the rates of the primary outcome (n= 547 total events; hazards ratio [95% confidence interval] = 0.99 [0.84–1.17]), or secondary outcomes of all-cause mortality (n=431 deaths; 1.04 [0.86–1.26]) or dialysis-dependent kidney failure (n=343 events; 1.15 [0.93–1.43]) compared to the low dose multivitamin. Conclusions Treatment with a high dose folic acid, B6, and B12 multivitamin in kidney transplant recipients did not reduce a composite cardiovascular disease outcome, all-cause mortality, or dialysis-dependent kidney failure despite significant reduction in homocysteine level. PMID:21482964

  20. Relationship between paraoxonase and homocysteine: crossroads of oxidative diseases

    PubMed Central

    2012-01-01

    Homocysteine (Hcy) is an accepted independent risk factor for several major pathologies including cardiovascular disease, birth defects, osteoporosis, Alzheimer's disease, and renal failure. Interestingly, many of the pathologies associated with homocysteine are also linked to oxidative stress. The enzyme paraoxonase (PON1) – so named because of its ability to hydrolyse the toxic metabolite of parathion, paraoxon – was also shown early after its identification to manifest arylesterase activity. Although the preferred endogenous substrate of PON1 remains unknown, lactones comprise one possible candidate class. Homocysteine-thiolactone can be disposed of by enzymatic hydrolysis by the serum Hcy-thiolactonase/paraoxonase carried on high-density lipoprotein (HDL). In this review, Hcy and the PON1 enzyme family were scrutinized from different points of view in the literature and the recent articles on these subjects were examined to determine whether these two molecular groups are related to each other like a coin with two different sides, so close and yet so different and so opposite. PMID:22457688

  1. Recurrence of the 'deep-intronic' FGG IVS6-320A>T mutation causing quantitative fibrinogen deficiency in the Italian population of Veneto.

    PubMed

    Platè, Manuela; Duga, Stefano; Castaman, Giancarlo; Rodeghiero, Francesco; Asselta, Rosanna

    2009-07-01

    Quantitative fibrinogen deficiency is a rare bleeding disorder characterized by abnormally low levels of fibrinogen in plasma, generally due to mutations in one of the three fibrinogen genes: FGA, FGB, and FGG, coding for A alpha, B beta, and gamma chain, respectively. Although the partial defect (hypofibrinogenemia) is due to mutations occurring in the heterozygous state, homozygosity or compound heterozygosity for the same genetic defects give rise to the more severe afibrinogenemia. Mutations responsible for these conditions are scattered throughout the three fibrinogen genes, with only few sites representing relative mutational hot spots. In this study, we report the identification of the FGG IVS6-320A>T mutation in an Italian hypofibrinogenemic patient from Veneto (a region of North-Eastern Italy). This 'deep-intronic' mutation, which would go unnoticed by using conventional mutational screening strategies was previously reported in an afibrinogenemic family from Vicenza (a province of Veneto). The geographic clustering of patients carrying the FGG IVS6-320A>T mutation and the results of haplotype analysis suggest the existence of a common founder. This information will be useful to direct future genetic screenings in patients coming from the same geographic area.

  2. Fibrinogen adsorption mechanisms at the gold substrate revealed by QCM-D measurements and RSA modeling.

    PubMed

    Kubiak, Katarzyna; Adamczyk, Zbigniew; Cieśla, Michał

    2016-03-01

    Adsorption kinetics of fibrinogen at a gold substrate at various pHs was thoroughly studied using the QCM-D method. The experimental were interpreted in terms of theoretical calculations performed according to the random sequential adsorption model (RSA). In this way, the hydration functions and water factors of fibrinogen monolayers were quantitatively evaluated at various pHs. It was revealed that for the lower range of fibrinogen coverage the hydration function were considerably lower than previously obtained for the silica sensor [33]. The lower hydration of fibrinogen monolayers on the gold sensor was attributed to its higher roughness. However, for higher fibrinogen coverage the hydration functions for both sensors became identical exhibiting an universal behavior. By using the hydration functions, the fibrinogen adsorption/desorption runs derived from QCM-D measurements were converted to the Γd vs. the time relationships. This allowed to precisely determine the maximum coverage that varied between 1.6mgm(-2) at pH 3.5 and 4.5mgm(-2) at pH 7.4 (for ionic strength of 0.15M). These results agree with theoretical eRSA modeling and previous experimental data derived by using ellipsometry, OWLS and TIRF. Various fibrinogen adsorption mechanisms were revealed by exploiting the maximum coverage data. These results allow one to develop a method for preparing fibrinogen monolayers of well-controlled coverage and molecule orientation.

  3. Binding of Efb from Staphylococcus aureus to fibrinogen blocks neutrophil adherence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In addition to its pivotal role in hemostasis, fibrinogen (Fg) and provisional fibrin matrices play important roles in inflammation and regulate innate immune responses by interacting with leukocytes. Efb (the extracellular fibrinogen-binding protein) is a secreted Staphylococcus aureus protein that...

  4. Fibrinogen drives dystrophic muscle fibrosis via a TGFβ/alternative macrophage activation pathway

    PubMed Central

    Vidal, Berta; Serrano, Antonio L.; Tjwa, Marc; Suelves, Mònica; Ardite, Esther; De Mori, Roberta; Baeza-Raja, Bernat; Martínez de Lagrán, María; Lafuste, Peggy; Ruiz-Bonilla, Vanessa; Jardí, Mercè; Gherardi, Romain; Christov, Christo; Dierssen, Mara; Carmeliet, Peter; Degen, Jay L.; Dewerchin, Mieke; Muñoz-Cánoves, Pura

    2008-01-01

    In the fatal degenerative Duchenne muscular dystrophy (DMD), skeletal muscle is progressively replaced by fibrotic tissue. Here, we show that fibrinogen accumulates in dystrophic muscles of DMD patients and mdx mice. Genetic loss or pharmacological depletion of fibrinogen in these mice reduced fibrosis and dystrophy progression. Our results demonstrate that fibrinogen–Mac-1 receptor binding, through induction of IL-1β, drives the synthesis of transforming growth factor-β (TGFβ) by mdx macrophages, which in turn induces collagen production in mdx fibroblasts. Fibrinogen-produced TGFβ further amplifies collagen accumulation through activation of profibrotic alternatively activated macrophages. Fibrinogen, by engaging its αvβ3 receptor on fibroblasts, also directly promotes collagen synthesis. These data unveil a profibrotic role of fibrinogen deposition in muscle dystrophy. PMID:18593877

  5. Fibrinogen residue γAla341 is necessary for calcium binding and 'A-a' interactions.

    PubMed

    Park, Rojin; Ping, Lifang; Song, Jaewoo; Hong, Sung-Yu; Choi, Tae-Youn; Choi, Jong-Rak; Gorkun, Oleg V; Lord, Susan T

    2012-05-01

    The fibrinogen γ-module has several important sites relating to fibrinogen function, which include the high affinity calcium binding site, hole 'a' that binds with knob 'A', and the D:D interface. Residue γAla341, which is located in the vicinity of these sites, is altered in three variant fibrinogens: fibrinogen Seoul (γAla341Asp), Tolaga Bay (γAla341Val), and Lyon III (γAla341Thr). In order to investigate the impaired polymerisation of fibrinogens γAla341Asp and γAla341Val to understand the role of γAla341 in fibrin polymerisation and fibrinogen synthesis, we have expressed γAla341Asp and γAla341Val in Chinese hamster ovary (CHO) cells, purified these fibrinogens from the culture media and performed biochemical tests to elucidate their function. Expression in CHO cells was similar for these variants. For both variants the kinetics of thrombin-catalysed FpA release was not different from normal fibrinogen, while FpB release was slower than that of normal. Thrombin-catalysed polymerisation of both variants was dependent on the calcium concentration. At physiologic calcium (1 mM) the variants showed impaired polymerisation with a longer lag period and a slower Vmax than normal fibrinogen. Scanning electron micrographs showed the clots were less organised than normal, having thicker and more twisted fibers, and larger pores. Analysis by SDS-PAGE showed that factor XIIIa-catalysed γ and α chain cross-linking was delayed, and plasmin-catalysed lysis was not reduced by the presence of 5 mM calcium or 5 mM GPRP (Gly-Pro-Arg-Pro). Our data indicate that fibrinogen residue γAla341 is important for the proper conformation of the γ-module, maintaining calcium-binding site and 'A-a' interactions.

  6. S-homoadenosyl-L-cysteine and S-homoadenosyl-L-homocysteine. Synthesis and binding studies of hon-hydrolyzed substrate analogues with S-adenosyl-L-homocysteine hydrolase.

    PubMed

    Miles, Robert W; Nielsen, Lars P C; Ewing, Gregory J; Yin, Daniel; Borchardt, Ronald T; Robins, Morris J

    2002-11-15

    Treatment of homoadenosine [9-(5-deoxy-beta-D-ribo-hexofuranosyl)adenine] with thionyl chloride and pyridine in acetonitrile gave 6'-chloro-6'-deoxyhomoadenosine, which underwent nucleophilic displacement with L-cysteine or L-homocysteine to give homologated analogues of S-adenosyl-L-homocysteine. Each amino acid in aqueous sodium hydroxide at 60 degrees C gave excellent conversion from the chloronucleoside, and adsorption on Amberlite XAD-4 resin provided more convenient isolation than prior methods. Weak binding of these non-hydrolyzed analogues to S-adenosyl-L-homocysteine hydrolase was observed.

  7. FDP-E induces adipocyte inflammation and suppresses insulin-stimulated glucose disposal: effect of inflammation and obesity on fibrinogen Bβ mRNA.

    PubMed

    Kang, Minsung; Vaughan, Roger A; Paton, Chad M

    2015-12-01

    Obesity is associated with increased fibrinogen production and fibrin formation, which produces fibrin degradation products (FDP-E and FDP-D). Fibrin and FDPs both contribute to inflammation, which would be expected to suppress glucose uptake and insulin signaling in adipose tissue, yet the effect of FDP-E and FDP-D on adipocyte function and glucose disposal is completely unknown. We tested the effects of FDPs on inflammation in 3T3-L1 adipocytes and primary macrophages and adipocyte glucose uptake in vitro. High-fat-fed mice increased hepatic fibrinogen mRNA expression ninefold over chow-fed mice, with concomitant increases in plasma fibrinogen protein levels. Obese mice also displayed increased fibrinogen content of epididymal fat pads. We treated cultured 3T3-L1 adipocytes and primary macrophages with FDP-E, FDP-D, or fibrinogen degradation products (FgnDP-E). FDP-D and FgnDP-E had no effect on inflammation or glucose uptake. Cytokine mRNA expression in RAW264.7 macrophage-like cells and 3T3-L1 adipocytes treated with FDP-E induced inflammation with maximal effects at 100 nM and 6 h. Insulin-stimulated 2-deoxy-d-[(3)H]glucose uptake was reduced by 71% in adipocytes treated with FDP-E. FDP-E, but not FDP-D or FgnDP-E, induces inflammation in macrophages and adipocytes and decreases glucose uptake in vitro. FDP-E may contribute toward obesity-associated acute inflammation and glucose intolerance, although its chronic role in obesity remains to be elucidated.

  8. Fibrinogen alpha and gamma genes and factor VLeiden in children with thromboembolism: results from 2 family-based association studies.

    PubMed

    Nowak-Göttl, Ulrike; Weiler, Hartmut; Hernandez, Irene; Thedieck, Sabine; Seehafer, Tanja; Schulte, Thomas; Stoll, Monika

    2009-08-27

    Previous case-control studies showed that genetic variation in the fibrinogen gamma gene (FGG) increased the risk for deep vein thrombosis (VT) in adults. We investigated the association between the fibrinogen alpha (FGA) and FGG haplotypes, the factor V(Leiden)-mutation, and pediatric VT and thromboembolic stroke (TS) in 2 independent study samples. Association analysis revealed that the FGA-H1 and FGG-H2 haplotypes were significantly overtransmitted to VT patients (FGA-H1, P = .05; FGG: H2, P = .032). In contrast, the FGG-H3 haplotype was undertransmitted (P = .022). In an independent study sample, FGA-H1 (P = .008) and FGG-H2 (P = .05) were significantly associated with TS. The association of FGA and FGG haplotypes with VT was more pronounced in FV(Leiden)-negative families (FGA-H1, P = .001; FGG-H2, P = .001), indicating a genetic interaction between both risk factors. The risk-conferring FGG-H2 and the protective FGG-H3 haplotypes correlated with low (FGG-H2) and high (FGG-H3) levels of the gamma' chain variant, respectively. These results provide independent and novel evidence that FGA-H1 and FGG-H2 variants are associated with an increased risk of VT and TS in children. The observed negative correlation of genetic VT risk with the plasma levels of the fibrinogen gamma' variant suggests that FGG-H2 and -H3 haplotypes modify thrombosis risk by controlling the level of this FGG splice isoform.

  9. Fibrinogen is not a prognostic factor for response to HELP-apheresis in sudden sensorineural hearing loss (SSHL).

    PubMed

    Berger, T; Kaiser, T; Scholz, M; Bachmann, A; Ceglarek, U; Hesse, G; Hagemeyer, B; Stumvoll, M; Thiery, J; Dietz, A

    2015-12-01

    Higher levels of fibrinogen or cholesterol were associated with improved hearing recovery in SSHL patients after treatment with HELP-apheresis (Heparin-induced extracorporeal LDL precipitation apheresis). The present trial was performed to demonstrate HELP-related effects on relevant metabolic and inflammatory parameters in the context of SSHL treatment. In the framework of a single arm non-controlled trial, we investigated the variation of metabolic and inflammatory parameters using HELP-apheresis for a defined group of 100 patients with SSHL. Based on cut off inclusion criteria (Serum LDL-cholesterol >1.6 g/l and/or fibrinogen >2.0 g/l, SSHL in minimum three frequencies more than 30 dB, time after event not longer than 6 days), the protocol followed a strict time line with one single shot HELP-apheresis and follow-up monitoring including laboratory parameters at six defined time points. If HELP-apheresis could not effect improvement of hearing on day 5, additional corticosteroid treatment was applied. Concentration of anti-inflammatory IL-10 increased while other proinflammatory parameters declined. Serum levels of all measured sterols and apolipoproteins decreased significantly. None of the investigated parameters were suitable to predict hearing improvement of the patients. Levels of fibrinogen and LDL-cholesterol were not prognostic for outcome after HELP-apheresis. A significant (p < 0.001) increase of anti-inflammatory IL-10 after apheresis was notable, while most of the proinflammatory parameters declined. Despite the limited validity of a single arm non-controlled trial, these alterations on immune modulating factors indicate possible secondary pleiotropic effects caused by HELP-apheresis.

  10. Are dietary choline and betaine intakes determinants of total homocysteine concentration?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Elevated homocysteine concentrations are associated with an increased risk of cardiovascular disease and a decline in cognitive function. Intakes of choline and betaine, as methyl donors, may affect homocysteine concentrations. The objective was to examine whether choline and betaine intakes, assess...

  11. Fibrinogen patterns and activity on substrates with tailored hydroxy density.

    PubMed

    Rodríguez Hernández, José Carlos; Rico, Patricia; Moratal, David; Monleón Pradas, Manuel; Salmerón-Sánchez, Manuel

    2009-08-11

    The influence of the surface fraction of OH groups on fibrinogen (FG) adsorption is investigated in copolymers of ethyl acrylate and hydroxy ethylacrylate. The amount of adsorbed FG, quantified by western-blotting combined with image analysis of the corresponding bands, decreases as the hydrophilicity of the substrate increases. The influence of substrate wettability on FG conformation and distribution is observed by atomic force microscopy (AFM). The most hydrophobic substrate promotes FG fibrillogenesis, which leads to a fibrin-like appearance in the absence of any thrombin. The degree of FG interconnection was quantified by calculating the fractal dimension of the adsorbed protein from image analysis of the AFM results. The biological activity of the adsorbed FG is correlated to cell adhesion on FG-coated substrates.

  12. Fibrinogen-fibrin conversion and inhibition of fibrinolysis.

    PubMed

    Stemberger, A; Blümel, G

    1982-08-01

    The fibrin adhesion technique is the imitation of the last step of the coagulation system. Fibrinogen is converted by thrombin into fibrin and stabilized by factor XIII. Fibrin sticks to the tissue and the tissue is adapted by syneresis. Local application of aprotinin to the thrombin solution is necessary in order to inhibit premature lysis of the fibrin film. This technique is now used in some selected cases in man such as fixation of cartilage, tendon, sealing of colonic anastomoses and preclotting of vessel grafts. An excellent hemostyptic effect of the fibrin glue in combination with absorbable collagen tampons was found. This combination technique is now used to seal parenchymatous organs and to stop hemorrhage in patients with defective hemostasis particularly those undergoing open heart surgery.

  13. Influence of Ficoll on urea induced denaturation of fibrinogen

    NASA Astrophysics Data System (ADS)

    Sankaranarayanan, Kamatchi; Meenakshisundaram, N.

    2016-03-01

    Ficoll is a neutral, highly branched polymer used as a molecular crowder in the study of proteins. Ficoll is also part of Ficoll-Paque used in biology laboratories to separate blood to its components (erythrocytes, leukocytes etc.,). Role of Ficoll in the urea induced denaturation of protein Fibrinogen (Fg) has been analyzed using fluorescence, circular dichroism, molecular docking and interfacial studies. Fluorescence studies show that Ficoll prevents quenching of Fg in the presence of urea. From the circular dichroism spectra, Fg shows conformational transition to random coil with urea of 6 M concentration. Ficoll helps to shift this denaturation concentration to 8 M and thus constraints by shielding Fg during the process. Molecular docking studies indicate that Ficoll interacts favorably with the protein than urea. The surface tension and shear viscosity analysis shows clearly that the protein is shielded by Ficoll.

  14. 5-fluorouracil loaded fibrinogen nanoparticles for cancer drug delivery applications.

    PubMed

    Rejinold, N Sanoj; Muthunarayanan, M; Chennazhi, K P; Nair, S V; Jayakumar, R

    2011-01-01

    In this study, 5-flurouracil loaded fibrinogen nanoparticles (5-FU-FNPs) were prepared by two step coacervation method using calcium chloride as cross-linker. The prepared nanoparticles were characterized using DLS, SEM, AFM, FT-IR, TG/DTA and XRD studies. Particle size of 5-FU-FNPs was found to be 150-200 nm. The loading efficiency (LE) and in vitro drug release was studied using UV spectrophotometer. The LE of FNPs was found to be ∼90%. The cytotoxicity studies showed 5-FU-FNPs were toxic to MCF7, PC3 and KB cells while they are comparatively non toxic to L929 cells. Cellular uptake of Rhodamine 123 conjugated 5-FU-FNPs was also studied. Cell uptake studies demonstrated that the nanoparticles are inside the cells. These results indicated that FNPs could be useful for cancer drug delivery. PMID:20951162

  15. Epistatic and pleiotropic effects of polymorphisms in the fibrinogen and coagulation factor XIII genes on plasma fibrinogen concentration, fibrin gel structure and risk of myocardial infarction.

    PubMed

    Mannila, Maria Nastase; Eriksson, Per; Ericsson, Carl-Göran; Hamsten, Anders; Silveira, Angela

    2006-03-01

    An intricate interplay between the genes encoding fibrinogen gamma (FGG), alpha (FGA) and beta (FGB), coagulation factor XIII (F13A1) and interleukin 6 (IL6) and environmental factors is likely to influence plasma fibrinogen concentration, fibrin clot structure and risk of myocardial infarction (MI). In the present study, the potential contribution of SNPs harboured in the fibrinogen, IL6 and F13A1 genes to these biochemical and clinical phenotypes was examined. A database and biobank based on 387 survivors of a first MI and population-based controls were used. Sixty controls were selected according to FGG 9340T > C [rs1049636] genotype for studies on fibrin clot structure using the liquid permeation method. The multifactor dimensionality reduction method was used for interaction analyses. We here report that the FGA 2224G > A [rs2070011] SNP (9.2%), plasma fibrinogen concentration (13.1%) and age (8.1%) appeared as independent determinants of fibrin gel porosity. The FGA 2224G > A SNP modulated the relation between plasma fibrinogen concentration and fibrin clot porosity. The FGG-FGA*4 haplotype, composed of the minor FGG 9340C and FGA 2224A alleles, had similar effects, supporting its reported protective role in relation to MI. Significant epistasis on plasma fibrinogen concentration was detected between the FGA 2224G > A and F13A1 Val34Leu [rs5985] SNPs (p < 0.001). The FGG 9340T > C and FGB 1038G > A [rs1800791] SNPs appeared to interact on MI risk, explaining the association of FGG-FGB haplotypes with MI in the absence of effects of individual SNPs. Thus, epistatic and pleiotropic effects of polymorphisms contribute to the variation in plasma fibrinogen concentration, fibrin clot structure and risk of MI.

  16. Homocysteine in renovascular complications: hydrogen sulfide is a modulator and plausible anaerobic ATP generator

    PubMed Central

    Sen, Utpal; Pushpakumar, Sathnur B.; Amin, Matthew A.; Tyagi, Suresh C.

    2014-01-01

    Homocysteine (Hcy) is a non-protein amino acid derived from dietary methionine. High levels of Hcy, known as hyperhomocysteinemia (HHcy) is known to cause vascular complications. In the mammalian tissue, Hcy is metabolized by transsulfuration enzymes to produce hydrogen sulfide (H2S). H2S, a pungent smelling gas was previously known for its toxic effects in the central nervous system, recent studies however has revealed protective effects in a variety of diseases including hypertension, diabetes, inflammation, atherosclerosis, and renal disease progression and failure. Interestingly, under stress conditions including hypoxia, H2S can reduce metabolic demand and also act as a substrate for ATP production. This review highlights some of the recent advances in H2S research as a potential therapeutic agent targeting renovascular diseases associated with HHcy. PMID:24963795

  17. Homocysteine in renovascular complications: hydrogen sulfide is a modulator and plausible anaerobic ATP generator.

    PubMed

    Sen, Utpal; Pushpakumar, Sathnur B; Amin, Matthew A; Tyagi, Suresh C

    2014-09-15

    Homocysteine (Hcy) is a non-protein amino acid derived from dietary methionine. High levels of Hcy, known as hyperhomocysteinemia (HHcy) is known to cause vascular complications. In the mammalian tissue, Hcy is metabolized by transsulfuration enzymes to produce hydrogen sulfide (H2S). H2S, a pungent smelling gas was previously known for its toxic effects in the central nervous system, recent studies however has revealed protective effects in a variety of diseases including hypertension, diabetes, inflammation, atherosclerosis, and renal disease progression and failure. Interestingly, under stress conditions including hypoxia, H2S can reduce metabolic demand and also act as a substrate for ATP production. This review highlights some of the recent advances in H2S research as a potential therapeutic agent targeting renovascular diseases associated with HHcy.

  18. Studies on N5-methyltetrahydrofolate-homocystein methyltransferase in normal and leukemia leukocytes.

    PubMed

    Peytremann, R; Thorndike, J; Beck, W S

    1975-11-01

    A cobalamin-dependent N5-methyltetra-hydrofolate-homocysteine methyltransferase (methyl-transferase) was demonstrated in unfractioned extracts of human normal and leukemia leukocytes. Activity was substantially reduced in the absence of an added cobalamin derivative. Presumably, this residual activity reflects the endogeneous level of holoenzyme. Enzyme activity was notably higher in lymphoid cells than in myeloid cells. Thus, mean specific activities (+/-SD) were: chronic lymphocytic leukemia lymphocytes, 2.15+/-1.16; normal lymphocytes, 0.91+/-0.59; normal mature granulocytes, 0.15+/-0.10; chronic myelocytic leukemia granulocytes, barely detectable activity. Properties of leukocytes enzymes resembled those of methyltransferases previously studied in bacteria and other animal cells. Granulocytes and chronic myelocytic leukemia cells contain a factor or factors that inhibits Escherichia coli enzyme. The data suggest that the prominence of this cobalamin-dependent enzyme in lymphocytes and other mononuclear cell types may be related to their potential for cell division.

  19. Studies on N5-methyltetrahydrofolate-homocystein methyltransferase in normal and leukemia leukocytes.

    PubMed Central

    Peytremann, R; Thorndike, J; Beck, W S

    1975-01-01

    A cobalamin-dependent N5-methyltetra-hydrofolate-homocysteine methyltransferase (methyl-transferase) was demonstrated in unfractioned extracts of human normal and leukemia leukocytes. Activity was substantially reduced in the absence of an added cobalamin derivative. Presumably, this residual activity reflects the endogeneous level of holoenzyme. Enzyme activity was notably higher in lymphoid cells than in myeloid cells. Thus, mean specific activities (+/-SD) were: chronic lymphocytic leukemia lymphocytes, 2.15+/-1.16; normal lymphocytes, 0.91+/-0.59; normal mature granulocytes, 0.15+/-0.10; chronic myelocytic leukemia granulocytes, barely detectable activity. Properties of leukocytes enzymes resembled those of methyltransferases previously studied in bacteria and other animal cells. Granulocytes and chronic myelocytic leukemia cells contain a factor or factors that inhibits Escherichia coli enzyme. The data suggest that the prominence of this cobalamin-dependent enzyme in lymphocytes and other mononuclear cell types may be related to their potential for cell division. PMID:1184750

  20. Fibrinogen modulates leukocyte recruitment in vivo during the acute inflammatory response.

    PubMed

    Vitorino de Almeida, V; Silva-Herdade, A; Calado, A; Rosário, H S; Saldanha, C

    2015-01-01

    Besides playing an important role in blood hemostases, fibrinogen also regulates leukocyte function in inflammation. Our previous in vitro studies showed that the adhesive behaviour of the neutrophil is modulated by soluble fibrinogen when present at a physiological concentration. This led us to propose that this plasma glycoprotein might further influence leukocyte recruitment in vivo and thus contribute to the inflammatory response. To address this in vivo, leukocyte recruitment was here investigated under acute inflammatory conditions in the absence of soluble fibrinogen in the blood circulation. For such, intravital microscopy on mesentery post-capillary venules was performed on homozygous fibrinogen α chain-deficient mice ((α-/-) mice). Acute inflammatory states were induced by perfusing platelet activating factor (PAF) over the exposed tissue. As control animals, two groups of mice expressing soluble fibrinogen in circulation were used, namely, C57BL/6 wild type animals and heterozygous fibrinogen α chain-deficient mice ((α+/-) mice). Under acute inflammatory conditions, an abnormal pattern of recruitment was observed for leukocytes in homozygous (α-/-) mice in comparison to both control groups. In fact, the former exhibited a significantly decreased number of rolling leukocytes that nevertheless, migrated with increased rolling velocities when compared to leukocytes from control animals. Consistently, homozygous mice further displayed a diminished number of adherent leukocytes than the other groups. Altogether our observations led us to conclude that leukocyte recruitment in homozygous (α-/-) mice is compromised what strongly suggests a role for soluble fibrinogen in leukocyte recruitment in inflammation.

  1. Fibrinogen Is at the Interface of Host Defense and Pathogen Virulence in Staphylococcus aureus Infection.

    PubMed

    Ko, Ya-Ping; Flick, Matthew J

    2016-06-01

    Fibrinogen not only plays a pivotal role in hemostasis but also serves key roles in antimicrobial host defense. As a rapidly assembled provisional matrix protein, fibrin(ogen) can function as an early line of host protection by limiting bacterial growth, suppressing dissemination of microbes to distant sites, and mediating host bacterial killing. Fibrinogen-mediated host antimicrobial activity occurs predominantly through two general mechanisms, namely, fibrin matrices functioning as a protective barrier and fibrin(ogen) directly or indirectly driving host protective immune function. The potential of fibrin to limit bacterial infection and disease has been countered by numerous bacterial species evolving and maintaining virulence factors that engage hemostatic system components within vertebrate hosts. Bacterial factors have been isolated that simply bind fibrinogen or fibrin, promote fibrin polymer formation, or promote fibrin dissolution. Staphylococcus aureus is an opportunistic gram-positive bacterium, the causative agent of a wide range of human infectious diseases, and a prime example of a pathogen exquisitely sensitive to host fibrinogen. Indeed, current data suggest fibrinogen serves as a context-dependent determinant of host defense or pathogen virulence in Staphylococcus infection whose ultimate contribution is dictated by the expression of S. aureus virulence factors, the path of infection, and the tissue microenvironment. PMID:27056151

  2. Adsorption Studies with AFM of Human Plasma Fibrinogen on Silicon Surfaces

    NASA Astrophysics Data System (ADS)

    Gause, Sheena; Kong, Wendy; Rowe

    2007-11-01

    Fibrinogen (FGN) plays an important role in the clotting of blood. Human plasma fibrinogen (HPF) is a protein that readily adsorbs on biomaterial surfaces. The purpose of this experiment was to use the Atomic Force Microscope to study the adsorption of HPF molecules or FGN onto several silicon surfaces with different orientations and resistivities. The size of the FGN molecules found to be somewhat different of Si(111), (100) and (110) were compared to the size of the FGN molecules in solution (45 nm in length, the end dynodes measures to be 6.5 nm in diameter, and the middle dynode measures to be 5 nm in diameter. For this study, the CPR (Thermo-microscope) Atomic Force Microscope (AFM) was used to observe the amount of fibrinogen molecules adsorbed by Si (111) with a resistance of .0281-.0261 φ cm, Si (111) with a resistance of 1 φ cm, Si (100), and Si (110) surfaces. In finding any single fibrinogen molecules, the appropriate image scans and measurements were taken. After collection and analysis of the data, it was found from AFM that the fibrinogen molecules found on Si (110) mostly resembled fibrinogen molecules found in solution. The other images showed that the fibrinogen molecules adsorbed on Silicon substrates is significantly greater (˜10-20 %) than those in solution.

  3. Contribution of haplotypes across the fibrinogen gene cluster to variation in risk of myocardial infarction.

    PubMed

    Mannila, Maria Nastase; Eriksson, Per; Lundman, Pia; Samnegård, Ann; Boquist, Susanna; Ericsson, Carl-Göran; Tornvall, Per; Hamsten, Anders; Silveira, Angela

    2005-03-01

    Fibrinogen has consistently been recognized as an independent predictor of myocardial infarction (MI). Multiple mechanisms link fibrinogen to MI; therefore disentangling the factors underlying variation in plasma fibrinogen concentration is essential. Candidate regions in the fibrinogen gamma (FGG), alpha (FGA) and beta (FGB) genes were screened for single nucleotide polymorphisms (SNPs). Several novel SNPs were detected in the FGG and FGA genes in addition to the previously known SNPs in the fibrinogen genes. Tight linkage disequilibrium extending over various physical distances was observed between most SNPs. Consequently, eight SNPs were chosen and determined in 377 postinfarction patients and 387 healthy individuals. None of the SNPs were associated with plasma fibrinogen concentration or MI. Haplotype analyses revealed a consistent pattern of haplotypes associated with variation in risk of MI. Of the four haplotypes inferred using the FGA -58G>A and FGG 1299 +79T>C SNPs, the most frequent haplotype, FGG-FGA*1 (prevalence 46.6%), was associated with increased risk of MI (OR 1.51; 95%CI 1.18, 1.93), whereas the least frequent haplotype, FGG-FGA*4 (11.8%), was associated with lower risk of MI (OR 0.79 95%CI 0.64, 0.98). In conclusion, fibrinogen haplotypes, but not SNPs in isolation, are associated with variation in risk of MI.

  4. Thrombin and fibrinogen γ' impact clot structure by marked effects on intrafibrillar structure and protofibril packing.

    PubMed

    Domingues, Marco M; Macrae, Fraser L; Duval, Cédric; McPherson, Helen R; Bridge, Katherine I; Ajjan, Ramzi A; Ridger, Victoria C; Connell, Simon D; Philippou, Helen; Ariëns, Robert A S

    2016-01-28

    Previous studies have shown effects of thrombin and fibrinogen γ' on clot structure. However, structural information was obtained using electron microscopy, which requires sample dehydration. Our aim was to investigate the role of thrombin and fibrinogen γ' in modulating fibrin structure under fully hydrated conditions. Fibrin fibers were studied using turbidimetry, atomic force microscopy, electron microscopy, and magnetic tweezers in purified and plasma solutions. Increased thrombin induced a pronounced decrease in average protofibril content per fiber, with a relatively minor decrease in fiber size, leading to the formation of less compact fiber structures. Atomic force microscopy under fully hydrated conditions confirmed that fiber diameter was only marginally decreased. Decreased protofibril content of the fibers produced by high thrombin resulted in weakened clot architecture as analyzed by magnetic tweezers in purified systems and by thromboelastometry in plasma and whole blood. Fibers produced with fibrinogen γ' showed reduced protofibril packing over a range of thrombin concentrations. High-magnification electron microscopy demonstrated reduced protofibril packing in γ' fibers and unraveling of fibers into separate protofibrils. Decreased protofibril packing was confirmed in plasma for high thrombin concentrations and fibrinogen-deficient plasma reconstituted with γ' fibrinogen. These findings demonstrate that, in fully hydrated conditions, thrombin and fibrinogen γ' have dramatic effects on protofibril content and that protein density within fibers correlates with strength of the fibrin network. We conclude that regulation of protofibril content of fibers is an important mechanism by which thrombin and fibrinogen γ' modulate fibrin clot structure and strength. PMID:26608329

  5. Contribution of the interaction of Streptococcus mutans serotype k strains with fibrinogen to the pathogenicity of infective endocarditis.

    PubMed

    Nomura, Ryota; Otsugu, Masatoshi; Naka, Shuhei; Teramoto, Noboru; Kojima, Ayuchi; Muranaka, Yoshinori; Matsumoto-Nakano, Michiyo; Ooshima, Takashi; Nakano, Kazuhiko

    2014-12-01

    Streptococcus mutans, a pathogen responsible for dental caries, is occasionally isolated from the blood of patients with bacteremia and infective endocarditis (IE). Our previous study demonstrated that serotype k-specific bacterial DNA is frequently detected in S. mutans-positive heart valve specimens extirpated from IE patients. However, the reason for this frequent detection remains unknown. In the present study, we analyzed the virulence of IE from S. mutans strains, focusing on the characterization of serotype k strains, most of which are positive for the 120-kDa cell surface collagen-binding protein Cbm and negative for the 190-kDa protein antigen (PA) known as SpaP, P1, antigen I/II, and other designations. Fibrinogen-binding assays were performed with 85 clinical strains classified by Cbm and PA expression levels. The Cbm(+)/PA(-) group strains had significantly higher fibrinogen-binding rates than the other groups. Analysis of platelet aggregation revealed that SA31, a Cbm(+)/PA(-) strain, induced an increased level of aggregation in the presence of fibrinogen, while negligible aggregation was induced by the Cbm-defective isogenic mutant SA31CBD. A rat IE model with an artificial impairment of the aortic valve created using a catheter showed that extirpated heart valves in the SA31 group displayed a prominent vegetation mass not seen in those in the SA31CBD group. These findings could explain why Cbm(+)/PA(-) strains are highly virulent and are related to the development of IE, and the findings could also explain the frequent detection of serotype k DNA in S. mutans-positive heart valve clinical specimens. PMID:25287921

  6. Effect of excess methionine and methionine hydroxy analogue on growth performance and plasma homocysteine of growing Pekin ducks.

    PubMed

    Xie, M; Hou, S S; Huang, W; Fan, H P

    2007-09-01

    One experiment was conducted to study the effect of excess dl-methionine (DLM) and dl-2-hydroxy-4-methylthiobutanoic acid free acid (dl-HMB-FA) on duck growth. One-day-old male white Pekin ducklings were fed common starter diets from hatch to 21 d of age and then fed the experimental diets from 21 to 42 d of age. Three hundred twenty 21-d-old birds were allotted to 40 raised wire-floor pens with 8 birds per pen according to similar pen weight. There were 5 dietary treatments that included a methionine-adequate control diet and control diets supplemented with 2 levels of dry DLM (1 or 2%) or 2 equimolar levels of liquid dl-HMB-FA (1.13 or 2.26%). Each dietary treatment was replicated 8 times. At 42 d of age, weight gain, feed intake, and gain/feed were measured and plasma was collected to analyze homocysteine. Compared with ducks fed control diets, excess DLM or dl-HMB-FA supplementation reduced weight gain and feed intake of birds significantly. However, on the equimolar basis, at 1 or 2% supplemental methionine activity, dl-HMB-FA was less growth-depressing than DLM. According to the growth response to excess methionine, the tolerable upper limit of dietary methionine for growing ducks may be less than 1.38% when the methionine level of the control diet (0.38%) was considered. On the other hand, plasma homocysteine was elevated markedly when 2% DLM or 2.26% dl-HMB-FA was added to control diets, but plasma homocysteine of ducks fed 2.26% dl-HMB-FA supplemented diets was lower significantly than birds fed equimolar DLM-supplemented diets, which indicated the toxicity of excess methionine sources and less toxicity of dl-HMB-FA relative to DLM.

  7. Central cardiovascular actions of L-homocysteine microinjected into ventrolateral medullary autonomic areas of the rat.

    PubMed

    Takemoto, Yumi

    2016-09-01

    Elevated L-homocysteine concentrations in the plasma and cerebrospinal fluid are related to cardiovascular and neuronal diseases, and could contribute to disease development. However, the central cardiovascular actions of L-homocysteine in two important autonomic regulating areas remain unknown: the rostral ventrolateral medulla (RVLM), including pre-sympathetic neurons, and the caudal ventrolateral medulla (CVLM), including interneurons projecting to pre-sympathetic neurons in the RVLM. Therefore, the aim of the current study was to examine the influence of L-homocysteine microinjected into the RVLM and CVLM areas on changes in arterial blood pressure (ABP) and heart rate (HR) of anesthetized rats, as well as the influence of ionotropic excitatory amino acid (iEAA) receptors on the central actions of L-homocysteine. L-Homocysteine solutions were microinjected into the RVLM and CVLM, which were defined according to pressor and depressor responses to L-glutamate microinjections, respectively. ABP and HR increased in the RVLM and decreased in the CVLM after microinjection with L-homocysteine, similar to L-glutamate, in a dose-dependent manner, suggesting mediation of EAA receptors. Prior microinjection of the N-methyl-D-aspartate (NMDA) iEAA receptor antagonist MK801, but not the non-NMDA receptor antagonist CNQX, abolished the observed responses to L-homocysteine in both the RVLM and CVLM. These results indicate the central cardiovascular actions of L-homocysteine via MK801-sensitive receptors of the medullary autonomic neurons in the rat RVLM and CVLM. It remains unknown if the central cardiovascular actions are related to cardiovascular diseases after endogenously and locally augmented L-homocysteine production by disordered metabolism. Further studies on functional significance of L-homocysteine may provide some clue to understand its toxic mechanism. PMID:27178024

  8. Central cardiovascular actions of L-homocysteine microinjected into ventrolateral medullary autonomic areas of the rat.

    PubMed

    Takemoto, Yumi

    2016-09-01

    Elevated L-homocysteine concentrations in the plasma and cerebrospinal fluid are related to cardiovascular and neuronal diseases, and could contribute to disease development. However, the central cardiovascular actions of L-homocysteine in two important autonomic regulating areas remain unknown: the rostral ventrolateral medulla (RVLM), including pre-sympathetic neurons, and the caudal ventrolateral medulla (CVLM), including interneurons projecting to pre-sympathetic neurons in the RVLM. Therefore, the aim of the current study was to examine the influence of L-homocysteine microinjected into the RVLM and CVLM areas on changes in arterial blood pressure (ABP) and heart rate (HR) of anesthetized rats, as well as the influence of ionotropic excitatory amino acid (iEAA) receptors on the central actions of L-homocysteine. L-Homocysteine solutions were microinjected into the RVLM and CVLM, which were defined according to pressor and depressor responses to L-glutamate microinjections, respectively. ABP and HR increased in the RVLM and decreased in the CVLM after microinjection with L-homocysteine, similar to L-glutamate, in a dose-dependent manner, suggesting mediation of EAA receptors. Prior microinjection of the N-methyl-D-aspartate (NMDA) iEAA receptor antagonist MK801, but not the non-NMDA receptor antagonist CNQX, abolished the observed responses to L-homocysteine in both the RVLM and CVLM. These results indicate the central cardiovascular actions of L-homocysteine via MK801-sensitive receptors of the medullary autonomic neurons in the rat RVLM and CVLM. It remains unknown if the central cardiovascular actions are related to cardiovascular diseases after endogenously and locally augmented L-homocysteine production by disordered metabolism. Further studies on functional significance of L-homocysteine may provide some clue to understand its toxic mechanism.

  9. Is the C677T polymorphism in methylenetetrahydrofolate reductase gene or plasma homocysteine a risk factor for diabetic peripheral neuropathy in Chinese individuals?

    PubMed

    Wang, Hongli; Fan, Dongsheng; Hong, Tianpei

    2012-10-25

    The present study enrolled 251 diabetic patients, including 101 with neuropathy and 150 without neuropathy. Of the 150 patients, 100 had no complications, such as retinopathy, nephropathy, or neuropathy. Polymerase chain reaction-restriction fragment length polymorphism analysis was used to identify methylenetetrahydrofolate reductase gene variants. Plasma homocysteine levels were also measured. Homocysteine levels and the frequency of hyperhomocysteinemia were significantly higher in patients with diabetic peripheral neuropathy compared with diabetic patients without neuropathy (P < 0.05). In logistic regression analysis with neuropathy as the dependent variable, the frequency of C677T in methylenetetrahydrofolate reductase was significantly higher in patients with diabetic peripheral neuropathy compared with patients without diabetic complications. Homocysteine levels were significantly higher in patients with diabetic peripheral neuropathy carrying the 677T allele and low folic acid levels. In conclusion, hyperhomocysteinemia is an independent risk factor for diabetic neuropathy in Chinese patients with diabetes. The C677T polymorphism in methylenetetrahydrofolate reductase and low folic acid levels may be risk factors for diabetic peripheral neuropathy in Chinese patients with diabetes.

  10. Multiple Novel Loci, Including Those Related to Crohn’s Disease, Psoriasis and Inflammation, Identified in a Genome-Wide Association Study of Fibrinogen in 17,686 Women: the Women’s Genome Health Study

    PubMed Central

    Danik, Jacqueline S.; Pare, Guillaume; Chasman, Daniel I.; Zee, Robert Y.L.; Kwiatkowski, David J.; Parker, Alex; Miletich, Joseph P.; Ridker, Paul M

    2009-01-01

    Background Fibrinogen is a multifunctional circulating glycoprotein involved in wound-healing, thrombosis, platelet aggregation and inflammation, and elevated levels predict vascular disease. Despite evidence of such crucial biological functions and moderate heritability, comprehensive analysis of the influence of genetic variation on fibrinogen is not available. Methods and Results To address this issue, we undertook a genome-wide association study evaluating the potential relationships between 337,343 single nucleotide polymorphisms (SNPs) and plasma fibrinogen levels among 17,686 apparently healthy women participating in the Women’s Genome Health Study (WGHS). As C-reactive protein is also an inflammatory marker known to predict cardiovascular diseases, we compared the determinants of fibrinogen levels with those of C-reactive protein. Four novel loci were identified, in addition to the fibrinogen gene cluster, which were associated with fibrinogen levels at genome-wide levels of significance (range of P-values from 8.82×10-09 to 8.04×10-39). Two of the loci related to common chronic inflammatory diseases: the first, at locus 5q31.1 (SLC22A5, SLC22A4, IRF1) lies immediately adjacent to a locus linked to Crohn’s disease (P-value for lead SNP 1.24 × 10-12) and the second, at locus 17q25.1 (CD300LF, SLC9A3R1, NAT9) has been associated with psoriasis (P-value for lead SNP 7.72×10-11). A third locus at 1q21.3 (IL6R) lies within the interleukin 6 receptor gene, a critical component of the inflammatory cascade (P-value for lead SNP 1.80×10-11). A novel locus at 2q34 (CPS1) participates in the urea cycle (P-value 8.82×10-09). The majority of implicated SNPs showed little evidence of dual association with C-reactive protein levels. Conclusions An agnostic survey of the human genome identifies novel loci related to common chronic inflammatory diseases as genetic determinants of fibrinogen levels, in addition to loci that relate to the inflammatory cascade, the

  11. Rapid extraction, radioiodination, and in vivo catabolism of 125I-labeled fibrinogen in the horse

    SciTech Connect

    Coyne, C.P.; Hornof, W.J.; Kelly, A.B.; O'Brien, T.R.; DeNardo, S.J.

    1985-12-01

    Two methods were analyzed for the rapid extraction of equine fibrinogen from fresh plasma, using ammonium sulfate-sodium phosphate buffer. Fibrinogen from each of these 2 methods was then radiolabeled with 125I (half-life = 60.2 days, gamma = 35 keV), using monochloroiodine reagent. Mean protein-bound activity was 98.5% and mean clottable radioactivity was 94.1%. Radiolabeled fibrinogen administered IV to 15 horses had an overall mean (+/- SD) plasma half-life of 4.95 +/- 0.44 days.

  12. Associations between Homocysteine, Folic Acid, Vitamin B12 and Alzheimer's Disease: Insights from Meta-Analyses.

    PubMed

    Shen, Liang; Ji, Hong-Fang

    2015-01-01

    The associations between homocysteine (Hcy), folic acid, and vitamin B12 and Alzheimer's disease (AD) have gained much interest, while remaining controversial. We aim to perform meta-analyses to evaluate comprehensively: i) Hcy, folic acid, and vitamin B12 levels in AD patients in comparison with controls; and ii) the association between Hcy, folic acid, and vitamin B12 levels and risk of AD. A literature search was performed using Medline and Scopus databases. A total of 68 studies were identified and included in the meta-analyses. Stata 12.0 statistical software was used to perform the meta-analyses. First, AD patients may have higher level of Hcy, and lower levels of folate and vitamin B12 in plasma than controls. Further age-subgroup analysis showed no age effect for Hcy levels in plasma between AD patients and matched controls, while the differences in folate and vitamin B12 levels further enlarged with increased age. Second, data suggests that high Hcy and low folate levels may correlate with increased risk of AD occurrence. The comprehensive meta-analyses not only confirmed higher Hcy, lower folic acid, and vitamin B12 levels in AD patients than controls, but also implicated that high Hcy and low folic acid levels may be risk factors of AD. Further studies are encouraged to elucidate mechanisms linking these conditions.

  13. Folic acid deficiency induces premature hearing loss through mechanisms involving cochlear oxidative stress and impairment of homocysteine metabolism.

    PubMed

    Martínez-Vega, Raquel; Garrido, Francisco; Partearroyo, Teresa; Cediel, Rafael; Zeisel, Steven H; Martínez-Álvarez, Concepción; Varela-Moreiras, Gregorio; Varela-Nieto, Isabel; Pajares, María A

    2015-02-01

    Nutritional imbalance is emerging as a causative factor of hearing loss. Epidemiologic studies have linked hearing loss to elevated plasma total homocysteine (tHcy) and folate deficiency, and have shown that folate supplementation lowers tHcy levels potentially ameliorating age-related hearing loss. The purpose of this study was to address the impact of folate deficiency on hearing loss and to examine the underlying mechanisms. For this purpose, 2-mo-old C57BL/6J mice (Animalia Chordata Mus musculus) were randomly divided into 2 groups (n = 65 each) that were fed folate-deficient (FD) or standard diets for 8 wk. HPLC analysis demonstrated a 7-fold decline in serum folate and a 3-fold increase in tHcy levels. FD mice exhibited severe hearing loss measured by auditory brainstem recordings and TUNEL-positive-apoptotic cochlear cells. RT-quantitative PCR and Western blotting showed reduced levels of enzymes catalyzing homocysteine (Hcy) production and recycling, together with a 30% increase in protein homocysteinylation. Redox stress was demonstrated by decreased expression of catalase, glutathione peroxidase 4, and glutathione synthetase genes, increased levels of manganese superoxide dismutase, and NADPH oxidase-complex adaptor cytochrome b-245, α-polypeptide (p22phox) proteins, and elevated concentrations of glutathione species. Altogether, our findings demonstrate, for the first time, that the relationship between hyperhomocysteinemia induced by folate deficiency and premature hearing loss involves impairment of cochlear Hcy metabolism and associated oxidative stress.

  14. Homocysteine enhances MMP-9 production in murine macrophages via ERK and Akt signaling pathways

    SciTech Connect

    Lee, Seung Jin; Lee, Yi Sle; Seo, Kyo Won; Bae, Jin Ung; Kim, Gyu Hee; Park, So Youn; Kim, Chi Dae

    2012-04-01

    Homocysteine (Hcy) at elevated levels is an independent risk factor of cardiovascular diseases, including atherosclerosis. In the present study, we investigated the effect of Hcy on the production of matrix metalloproteinases (MMP) in murine macrophages. Among the MMP known to regulate the activities of collagenase and gelatinase, Hcy exclusively increased the gelatinolytic activity of MMP-9 in J774A.1 cells as well as in mouse peritoneal macrophages. Furthermore, this activity was found to be correlated with Western blot findings in J774A.1 cells, which showed that MMP-9 expression was concentration- and time-dependently increased by Hcy. Inhibition of the ERK and Akt pathways led to a significant decrease in Hcy-induced MMP-9 expression, and combined treatment with inhibitors of the ERK and Akt pathways showed an additive effects. Activity assays for ERK and Akt showed that Hcy increased the phosphorylation of both, but these phosphorylation were not affected by inhibitors of the Akt and ERK pathways. In line with these findings, the molecular inhibition of ERK and Akt using siRNA did not affect the Hcy-induced phosphorylation of Akt and ERK, respectively. Taken together, these findings suggest that Hcy enhances MMP-9 production in murine macrophages by separately activating the ERK and Akt signaling pathways. -- Highlights: ► Homocysteine (Hcy) induced MMP-9 production in murine macrophages. ► Hcy induced MMP-9 production through ERK and Akt signaling pathways. ► ERK and Akt signaling pathways were activated by Hcy in murine macrophages. ► ERK and Akt pathways were additively act on Hcy-induced MMP-9 production. ► Hcy enhances MMP-9 production in macrophages via activation of ERK and Akt signaling pathways in an independent manner.

  15. Using competitive protein adsorption to measure fibrinogen in undiluted human serum

    NASA Astrophysics Data System (ADS)

    Choi, Seokheun; Wang, Ran; Lajevardi-Khosh, Arad; Chae, Junseok

    2010-12-01

    We report a unique sensing mechanism based on competitive protein adsorption to measure fibrinogen, a cardiovascular biomarker, in undiluted human serum. The method uses physical adsorption of proteins to a surface rather than complex and time-consuming immobilization procedures. Two fibrinogen concentrations were differentiated in spiked in human serum [3.0 mg/ml (normal concentration) versus 3.2 mg/ml (abnormal concentration with heart disease)]. Real-time surface plasmon resonance signals were monitored as fibrinogen displaced a preadsorbed protein, IgM, on a hydrophobic gold surface. The relatively strong-affinity protein, IgM, was displaced primarily by fibrinogen and much less by other proteins in human serum.

  16. Gallium nitrate induces fibrinogen flocculation: an explanation for its hemostatic effect?

    PubMed

    Bauters, A; Holt, D J; Zerbib, P; Rogosnitzky, M

    2013-12-01

    A novel hemostatic effect of gallium nitrate has recently been discovered. Our aim was to perform a preliminary investigation into its mode of action. Thromboelastography® showed no effect on coagulation but pointed instead to changes in fibrinogen concentration. We measured functional fibrinogen in whole blood after addition of gallium nitrate and nitric acid. We found that gallium nitrate induces fibrinogen precipitation in whole blood to a significantly higher degree than solutions of nitric acid alone. This precipitate is not primarily pH driven, and appears to occur via flocculation. This behavior is in line with the generally observed ability of metals to induce fibrinogen precipitation. Further investigation is required into this novel phenomenon.

  17. The molecular basis of the antiplatelet action of ajoene: direct interaction with the fibrinogen receptor.

    PubMed

    Apitz-Castro, R; Ledezma, E; Escalante, J; Jain, M K

    1986-11-26

    Ajoene, the major antiplatelet compound derived from garlic inhibits the fibrinogen-supported aggregation of washed human platelets (ID50 = 13 microM) and, inhibits binding of 125I-fibrinogen to ADP-stimulated platelets (ID50 = 0.8 microM). In both cases, the inhibition is of the mixed non-competitive type. Furthermore, fibrinogen-induced aggregation of chymotrypsin-treated platelets is also inhibited by ajoene in a dose-dependent manner (ID50 = 2.3 microM). Other membrane receptors such as ADP or epinephrine receptors are not affected by ajoene. Ajoene strongly quenches the intrinsic fluorescence emission of purified glycoproteins IIb-IIIa (ID50 = 10 microM). These results indicate that the antiaggregatory effect of ajoene is causally related to its direct interaction with the putative fibrinogen receptor.

  18. Discrimination between Fibrin and Fibrinogen by a Monoclonal Antibody against a Synthetic Peptide

    NASA Astrophysics Data System (ADS)

    Scheefers-Borchel, Ursula; Muller-Berghaus, Gert; Fuhge, Peter; Eberle, Reinhard; Heimburger, Nobert

    1985-10-01

    Circulating soluble fibrin, observed in the blood of patients with ongoing intravascular coagulation, is generated from the plasma protein fibrinogen by the limited proteolytic action of thrombin. We report the production of a monoclonal antibody that discriminates between fibrin and fibrinogen in blood. The synthetic hexapeptide Gly-Pro-Arg-Val-Val-Glu, representing the amino terminus of the α chain of human fibrin, was used as immunogen. This hexapeptide is located within the Aα chain of fibrinogen but becomes the amino terminus of the fibrin α chain, after fibrinopeptide A is removed by the action of thrombin, and thus becomes accessible for antibody binding. The monoclonal antibody we have prepared can discriminate between fibrin and fibrinogen and thus can be used in assay systems to quantitate soluble fibrin or, potentially, to image fibrin-rich thrombi.

  19. Characterization of a cDNA clone coding for the beta chain of bovine fibrinogen.

    PubMed Central

    Chung, D W; Rixon, M W; MacGillivray, R T; Davie, E W

    1981-01-01

    Recombinant plasmids containing bovine cDNA have been screened with a radiolabeled cDNA enriched for bovine fibrinogen. A number of plasmids containing cDNAs for fibrinogen were identified by this assay. One plasmid, designated pBI beta 1, was found to contain a cDNA insert of 1372 base pairs. The sequence of the cDNA insert for this plasmid was then determined. It was shown to code for 424 amino acids of the beta chain of fibrinogen, starting with residue 44. This and other data made it possible to construct the complete amino acid sequence of the beta chain of the protein. Comparison of the amino acid sequence of the beta chain of bovine fibrinogen with the corresponding chain of the human molecule indicated that the two chains are greater than 80% homologous. PMID:6262803

  20. Folic Acid and Vitamins D and B12 Correlate With Homocysteine in Chinese Patients With Type-2 Diabetes Mellitus, Hypertension, or Cardiovascular Disease.

    PubMed

    Mao, Xudong; Xing, Xubin; Xu, Rong; Gong, Qing; He, Yue; Li, Shuijun; Wang, Hongfu; Liu, Cong; Ding, Xin; Na, Rishu; Liu, Zhiwen; Qu, Yi

    2016-02-01

    Elevated serum homocysteine has been shown to be a risk factor for hypertension, cardiovascular disease (CVD), and type-2 diabetes mellitus (T2DM).We characterized the relationships between the serum levels of homocysteine, folic acid, and vitamins D2, D3, and B12 in patients with T2DM, CVD, and hypertension in Shanghai, China. The levels of these serum biochemical markers were determined for 9311 Chinese patients (mean age: 79.50 ± 13.26 years) with T2DM (N = 839), hypertension (N = 490), or CVD (N = 7925). The demographic and serum biochemical data were compared using an analysis of variance. We performed stratified analyses using Pearson linear regression to investigate correlations between the different variables in the T2DM, CVD, and hypertension groups and in patients aged < 50, 50 to 64, 65 to 80, and ≥80 years. A subgroup analysis was also performed to identify correlations between the serum biochemical markers. Stratified chi-squared analyses were performed based on the levels of folic acid and total vitamin D.In all 3 patient groups, elevated levels of vitamin D2 and homocysteine were observed, whereas the levels of folic acid and vitamins D3 and B12 were lower than the reference range for each serum marker (P < 0.05 for all). The linear regression and stratified analyses showed that the highest levels of folic acid and vitamins D2 and D3 correlated with the lowest level of homocysteine in T2DM, CVD, and hypertension patients (P < 0.05 for all), whereas the highest level of vitamin B12 correlated with a lowest level of homocysteine in CVD patients only (P < 0.05).Our results indicate that the contributions of both vitamin D2 and vitamin D3 should be considered in investigations of the effects of vitamin D supplements in T2DM, CVD, and hypertension patients. Our findings warrant future studies of the benefits of vitamin D and folic acid supplements for reducing the risk of T2DM, CVD, and hypertension in elderly Chinese

  1. Impaired homocysteine metabolism in patients with alcoholic liver disease in Taiwan.

    PubMed

    Chien, Yi-Wen; Chen, Ya-Ling; Peng, Hsiang-Chi; Hu, Jui-Ting; Yang, Sien-Sing; Yang, Suh-Ching

    2016-08-01

    ​Impaired homocysteine metabolism plays an important role in alcoholic liver disease (ALD); however, there are limited data about its relationship with the risk and severity of patients with ALD in Taiwan. To understand plasma homocysteine and related vitamin concentrations in patients with ALD in Taiwan, we recruited 50 male patients with ALD from Cathay General Hospital, with 49 age-and gender-matched healthy adults as the control group. The Institutional Review Board for Human Studies approved the study, and informed consent was obtained from all patients prior to blood collection. Significantly higher plasma homocysteine concentrations but lower folate concentrations were obtained from patients with ALD. In addition, patients with ALD showed a significant lower erythrocyte reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio but higher plasma thiobarbituric acid-reactive substance (TBARS) concentration, which indicated that oxidative stress was occurring in patients with ALD. A negative correlation between plasma folate and homocysteine was observed in all subjects. There was also a negative correlation between plasma homocysteine and the erythrocyte GSH/GSSG ratio which indicated impaired homocysteine metabolism may have disrupted the antioxidative status. In addition, patients in Child-Pugh Class B and C showed higher plasma vitamin B12 concentrations than did patients without cirrhosis and patients in Child-Pugh Class A. These findings show that impaired homocysteine metabolism was observed in patients with ALD in Taiwan. In addition, the plasma vitamin B12 concentration may reflect the degree of liver injury. PMID:27565754

  2. Higher intake of vitamin B-6 and dairy products and lower intake of green and oolong tea are independently associated with lower serum homocysteine concentration in young Japanese women.

    PubMed

    Murakami, Kentaro; Sasaki, Satoshi; Uenishi, Kazuhiro

    2013-08-01

    Little is known about the relation of modifiable dietary factors to circulating homocysteine concentrations, particularly in young adults and non-Western populations. We investigated the hypothesis that intakes of nutrients and foods are associated with serum homocysteine concentration in a group of young Japanese women. This cross-sectional study included 1050 female Japanese dietetic students aged 18 to 22 years. Dietary intake was assessed using a validated, self-administered, comprehensive diet history questionnaire. Fasting blood samples were collected, and serum homocysteine concentrations were measured. Adjustment was made for survey year, region, municipality level, current smoking, current alcohol drinking, dietary supplement use, physical activity, body mass index, energy intake, and intakes of other nutrients or foods. After adjustment for nondietary confounding factors, intakes of all B vitamins (folate, vitamin B-6, vitamin B-12, and riboflavin) were inversely associated with homocysteine concentration. However, only vitamin B-6 remained significant after further adjustment for other B vitamins. Marine-origin n-3 polyunsaturated fatty acid intake showed an inverse association, but this was not independent of intakes of B vitamins. For foods, pulses, fish and shellfish, and vegetables were independently and inversely associated with homocysteine concentration, but these associations disappeared after adjustment for intakes of other foods. Conversely, an inverse association for dairy products and a positive association for green and oolong tea remained even after adjustment for other foods. To conclude, in a group of young Japanese women, higher intake of vitamin B-6 and dairy products and lower intake of green and oolong tea were independently associated with lower serum homocysteine concentration.

  3. LIMITATIONS OF FIBRINOGEN-POLYMYXIN MEDIUM IN DETECTING COAGULASE-POSITIVE STAPHYLOCOCCI IN RAW MILK.

    PubMed

    MCDIVITT, M E; JEROME, N W

    1965-03-01

    A fibrinogen-polymyxin medium and Staphylococcus Medium 110 were used in the isolation of coagulase-positive staphylococci in raw milk. Results indicated that both media allow the growth of some rods and of many coagulase-negative cocci. A significantly greater number of coagulase-positive staphylococci were identified by the tube test than were revealed by halo formation on fibrinogen-polymyxin medium.

  4. Characterization of the fibrinogen binding domain of bacteriophage lysin from Streptococcus mitis.

    PubMed

    Seo, Ho Seong; Sullam, Paul M

    2011-09-01

    The binding of bacteria to human platelets is a likely central mechanism in the pathogenesis of infective endocarditis. Platelet binding by Streptococcus mitis SF100 is mediated in part by a lysin encoded by the lysogenic bacteriophage SM1. In addition to its role in the phage life cycle, lysin mediates the binding of S. mitis to human platelets via its interaction with fibrinogen on the platelet surface. To better define the region of lysin mediating fibrinogen binding, we tested a series of purified lysin truncation variants for their abilities to bind this protein. These studies revealed that the fibrinogen binding domain of lysin is contained within the region spanned by amino acid residues 102 to 198 (lysin(102-198)). This region has no sequence homology to other known fibrinogen binding proteins. Lysin(102-198) bound fibrinogen comparably to full-length lysin and with the same selectivity for the fibrinogen Aα and Bβ chains. Lysin(102-198) also inhibited the binding in vitro of S. mitis to human fibrinogen and platelets. When assessed by platelet aggregometry, the disruption of the lysin gene in SF100 resulted in a significantly longer time to the onset of aggregation of human platelets than that of the parent strain. The preincubation of platelets with purified lysin(102-198) also delayed the onset of aggregation by SF100. These results indicate that the binding of lysin to fibrinogen is mediated by a specific domain of the phage protein and that this interaction is important for both platelet binding and aggregation by S. mitis. PMID:21690235

  5. The relationship between copper, homocysteine and early vascular disease in lean women with polycystic ovary syndrome.

    PubMed

    Celik, Cem; Bastu, Ercan; Abali, Remzi; Alpsoy, Seref; Guzel, Eda Celik; Aydemir, Birsen; Yeh, John

    2013-05-01

    This study investigates copper (Cu) levels and vascular dysfunction in lean women with polycystic ovary syndrome (PCOS). 44 subjects with PCOS, diagnosed according to Rotterdam criteria, and 42 healthy subjects matched for body mass index and age. Comparison of serum Cu, homocysteine, carotid intima-media thickness (CIMT), brachial artery flow mediated dilation (FMD) was carried out between PCOS patients and the control group. Clinical study was done in Namik Kemal University School of Medicine. The CIMT and concentration of Cu in PCOS patients was significantly higher than the healthy controls. FMD levels in PCOS patients were significantly lower than those in controls. In PCOS patients, CIMT was correlated with estrogen and Cu levels. However, FMD was correlated with age and Cu levels. Among these contributing factors, Cu levels were correlated with a change in CIMT and FMD. CIMT and FMD in PCOS patients were related to Cu levels as well as several cardiovascular risk factors. Thus, increased Cu levels may be responsible for the increased risk of early vascular disease in women with PCOS.

  6. Genome-wide meta-analysis of homocysteine and methionine metabolism identifies five one carbon metabolism loci and a novel association of ALDH1L1 with ischemic stroke

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Circulating homocysteine levels (tHcy), a product of the folate one carbon metabolism pathway (FOCM) through the demethylation of methionine, are heritable and are associated with an increased risk of common diseases such as stroke, cardiovascular disease (CVD), cancer and dementia. The FOCM is the ...

  7. Evolutionary Analyses and Natural Selection of Betaine-Homocysteine S-Methyltransferase (BHMT) and BHMT2 Genes

    PubMed Central

    Ganu, Radhika S.; Ishida, Yasuko; Koutmos, Markos; Kolokotronis, Sergios-Orestis; Roca, Alfred L.; Garrow, Timothy A.; Schook, Lawrence B.

    2015-01-01

    Betaine-homocysteine S-methyltransferase (BHMT) and BHMT2 convert homocysteine to methionine using betaine and S-methylmethionine, respectively, as methyl donor substrates. Increased levels of homocysteine in blood are associated with cardiovascular disease. Given their role in human health and nutrition, we identified BHMT and BHMT2 genes and proteins from 38 species of deuterostomes including human and non-human primates. We aligned the genes to look for signatures of selection, to infer evolutionary rates and events across lineages, and to identify the evolutionary timing of a gene duplication event that gave rise to two genes, BHMT and BHMT2. We found that BHMT was present in the genomes of the sea urchin, amphibians, reptiles, birds and mammals; BHMT2 was present only across mammals. BHMT and BHMT2 were present in tandem in the genomes of all monotreme, marsupial and placental species examined. Evolutionary rates were accelerated for BHMT2 relative to BHMT. Selective pressure varied across lineages, with the highest dN/dS ratios for BHMT and BHMT2 occurring immediately following the gene duplication event, as determined using GA Branch analysis. Nine codons were found to display signatures suggestive of positive selection; these contribute to the enzymatic or oligomerization domains, suggesting involvement in enzyme function. Gene duplication likely occurred after the divergence of mammals from other vertebrates but prior to the divergence of extant mammalian subclasses, followed by two deletions in BHMT2 that affect oligomerization and methyl donor specificity. The faster evolutionary rate of BHMT2 overall suggests that selective constraints were reduced relative to BHMT. The dN/dS ratios in both BHMT and BHMT2 was highest following the gene duplication, suggesting that purifying selection played a lesser role as the two paralogs diverged in function. PMID:26213999

  8. Hepatocyte-specific Dyrk1a gene transfer rescues plasma apolipoprotein A-I levels and aortic Akt/GSK3 pathways in hyperhomocysteinemic mice.

    PubMed

    Tlili, Asma; Jacobs, Frank; de Koning, Leanne; Mohamed, Sirine; Bui, Linh-Chi; Dairou, Julien; Belin, Nicole; Ducros, Véronique; Dubois, Thierry; Paul, Jean-Louis; Delabar, Jean-Maurice; De Geest, Bart; Janel, Nathalie

    2013-06-01

    Hyperhomocysteinemia, characterized by high plasma homocysteine levels, is recognized as an independent risk factor for cardiovascular diseases. The increased synthesis of homocysteine, a product of methionine metabolism involving B vitamins, and its slower intracellular utilization cause increased flux into the blood. Plasma homocysteine level is an important reflection of hepatic methionine metabolism and the rate of processes modified by B vitamins as well as different enzyme activity. Lowering homocysteine might offer therapeutic benefits. However, approximately 50% of hyperhomocysteinemic patients due to cystathionine-beta-synthase deficiency are biochemically responsive to pharmacological doses of B vitamins. Therefore, effective treatments to reduce homocysteine levels are needed, and gene therapy could provide a novel approach. We recently showed that hepatic expression of DYRK1A, a serine/threonine kinase, is negatively correlated with plasma homocysteine levels in cystathionine-beta-synthase deficient mice, a mouse model of hyperhomocysteinemia. Therefore, Dyrk1a is a good candidate for gene therapy to normalize homocysteine levels. We then used an adenoviral construct designed to restrict expression of DYRK1A to hepatocytes, and found decreased plasma homocysteine levels after hepatocyte-specific Dyrk1a gene transfer in hyperhomocysteinemic mice. The elevation of pyridoxal phosphate was consistent with the increase in cystathionine-beta-synthase activity. Commensurate with the decreased plasma homocysteine levels, targeted hepatic expression of DYRK1A resulted in elevated plasma paraoxonase-1 activity and apolipoprotein A-I levels, and rescued the Akt/GSK3 signaling pathways in aorta of mice, which can prevent homocysteine-induced endothelial dysfunction. These results demonstrate that hepatocyte-restricted Dyrk1a gene transfer can offer a useful therapeutic targets for the development of new selective homocysteine lowering therapy. PMID:23429073

  9. Attachment of staphylococci and streptococci on fibronectin, fibronectin fragments, and fibrinogen bound to a solid phase.

    PubMed Central

    Kuusela, P; Vartio, T; Vuento, M; Myhre, E B

    1985-01-01

    The attachment of Staphylococcus aureus (Cowan I) and two strains of group A and G streptococci on glass cover slips coated with fibronectin, fibronectin fragments, or fibrinogen was studied. The attachment was quantitated by counting the attached bacteria on glass surfaces coated with a similar molarity of the proteins. Fibronectin was a more effective attachment factor than fibrinogen for staphylococci, while group G streptococci attached better on fibrinogen- than on fibronectin-coated cover slips. In this system, group A streptococci bound almost exclusively to substrate-bound fibrinogen. Attachment experiments involving the use of staphylococci pretreated with soluble fibronectin or fibrinogen revealed that bacterium-bound fibronectin and fibrinogen were able to enhance the adherence on cover slips coated with fibronectin. The 30-kilodalton NH2-terminal and the 120- to 140-kilodalton COOH-terminal fragments of fibronectin, both of which contain bacterial binding sites, mediated the staphylococcal attachment, suggesting that both parts of the molecule are involved in the attachment mediated by fibronectin. PMID:3899940

  10. Evaluation of the viability of /sup 111/In-abeled DTPA coupled to fibrinogen

    SciTech Connect

    Layne, W.W.; Hnatowich, D.J.; Doherty, P.W.; Childs, R.L.; Lanteigne, D.; Ansell, J.

    1982-07-01

    In earlier work, DTPA has been covalently coupled to albumin via the cyclic anhydride of DTPA. Using fibrinogen, we have studied the effect of such coupling on protein viability by both an in vitro and an in vivo assay. Clotting time remained identical to that of the native protein whether the anhydride-to-protein molar ratio was 1:1 or 5:1. In vivo studies were done in dogs, with human fibrinogen labeled with /sup 125/I and /sup 111/In. Throughout 130 hr, blood clearances for the two tracers agreed whether with 1:1 or 5:1 coupling. In a dog model with a thrombogenic catheter, the clot-to-blood ratios for the two radiotracers agreed within experimental error. Finally, 1:1-coupled canine fibrinogen, labeled with /sup 111/In, was administered to dogs with a catheter in a jugular vein, and scintigrams at 24 hr clearly showed clotting along the length of the catheter. We conclude that fibrinogen, coupled to DTPA, retains its viability, behaving like radioiodinated fibrinogen in vivo, and /sup 111/In labeled fibrinogen looks promising as a clinical diagnostic agent.

  11. The Internal Dynamics of Fibrinogen and Its Implications for Coagulation and Adsorption

    PubMed Central

    Köhler, Stephan; Schmid, Friederike; Settanni, Giovanni

    2015-01-01

    Fibrinogen is a serum multi-chain protein which, when activated, aggregates to form fibrin, one of the main components of a blood clot. Fibrinolysis controls blood clot dissolution through the action of the enzyme plasmin, which cleaves fibrin at specific locations. Although the main biochemical factors involved in fibrin formation and lysis have been identified, a clear mechanistic picture of how these processes take place is not available yet. This picture would be instrumental, for example, for the design of improved thrombolytic or anti-haemorrhagic strategies, as well as, materials with improved biocompatibility. Here, we present extensive molecular dynamics simulations of fibrinogen which reveal large bending motions centered at a hinge point in the coiled-coil regions of the molecule. This feature, likely conserved across vertebrates according to our analysis, suggests an explanation for the mechanism of exposure to lysis of the plasmin cleavage sites on fibrinogen coiled-coil region. It also explains the conformational variability of fibrinogen observed during its adsorption on inorganic surfaces and it is supposed to play a major role in the determination of the hydrodynamic properties of fibrinogen. In addition the simulations suggest how the dynamics of the D region of fibrinogen may contribute to the allosteric regulation of the blood coagulation cascade through a dynamic coupling between the a- and b-holes, important for fibrin polymerization, and the integrin binding site P1. PMID:26366880

  12. Fibrinogen-binding properties of the human platelet glycoprotein IIb-IIIa complex: a study using crossed-radioimmunoelectrophoresis

    SciTech Connect

    Gogstad, G.O.; Brosstad, F.; Krutnes, M.B.; Hagen, I.; Solum, N.O.

    1982-09-01

    Fibrinogen-binding platelet proteins have been examined by crossed-immunoelectrophoresis of solubilized, washed platelets followed by the incubation of the immunoplates with /sup 125/I-fibrinogen and exposure to x-ray films. Incubation with 0.1 mg/ml of /sup 125/I-fibrinogen revealed the binding of fibrinogen to the immunoprecipitates representing the glycoprotein IIb-IIIa complex, factor XIIIa chain, a granule membrane protein termed G4, fibrinogen, and albumin. Only the glycoprotein IIb-IIIa precipitate and the fibrinogen precipitate showed significant binding when the concentration of /sup 125/I-fibrinogen was lowered to 0.01 mg/ml. Thi indicates that the binding of fibrinogen is specific. The binding of /sup 125/I-fibrinogen to the precipitates representing the glycoprotein IIb-IIIa complex, the factor XIIIa chain, and G4, but not to the albumin precipitate, was significantly lowered in the presence of EDTA. This effect of EDTA increased with increasing pH, with no binding at pH 8.7. The results indicate that the glycoprotein IIb-IIIa complex, but not the separate glycoproteins IIb and IIIa, can act as Ca/sup 2 +/ or Mg/sup 2 +/-dependent fibrinogen receptor, under proper physiologic conditions.

  13. [The role of homocysteine and methylenetetrahydrofolate reductase, methionine synthase, methionine synthase reductase polymorphisms in the development of cardiovascular diseases and hypertension].

    PubMed

    Marosi, Krisztina; Agota, Annamária; Végh, Veronika; Joó, József Gábor; Langmár, Zoltán; Kriszbacher, Ildikó; Nagy, Zsolt B

    2012-03-25

    Cardiovascular diseases (CVDs) are the leading causes of death in the developed countries. Elevated homocysteine level is as an independent risk factor of CVDs. The C677T and A1298C variants of methylenetetrahydrofolate reductase gene (MTHFR) have been shown to influence folate and homocysteine metabolisms. However, the relationship between MTHFR polymorphisms and hyperhomocysteinemia has not been well established yet. The gene variants were also reported to be associated with CVDs. In addition, the C677T polymorphisms may play a role in the development of hypertension. Recent research evidence has suggested that MTHFR variants might be independently linked to CVDs and hypertension, because of the involvement of the MTHFR enzyme product (5-methyl-tetrahydrofolate /5-MTHF) in the regulation of endothelial functions. Further research is required to investigate the association between gene polymorphisms of folate-metabolizing enzymes and CVDs, and to identify the possible role of the relevant gene variants in the molecular pathogenesis of hyperhomocysteinemia.

  14. A hemocyte-expressed fibrinogen-related protein gene (LvFrep) from the shrimp Litopenaeus vannamei: Expression analysis after microbial infection and during larval development.

    PubMed

    Coelho, Jaqueline da Rosa; Barreto, Cairé; Silveira, Amanda da Silva; Vieira, Graziela Cleusa; Rosa, Rafael Diego; Perazzolo, Luciane Maria

    2016-09-01

    Fibrinogen-related proteins (FREPs) comprise a large family of microbial recognition proteins involved in many biological functions in both vertebrate and invertebrate animals. By taking advantage of publicly accessible databases, we have identified a FREP-like homolog in the most cultivated penaeid shrimp, Litopenaeus vannamei (LvFrep). The obtained sequence showed a conserved fibrinogen-related domain (FReD) and displayed significant similarities to FREP-like proteins from other invertebrates and to ficolins from crustaceans. The expression of LvFrep appeared to be limited to circulating hemocytes. Interestingly, LvFrep gene expression was induced in shrimp hemocytes only in response to a Vibrio infection but not to the White spot syndrome virus (WSSV). Moreover, LvFrep transcript levels were detected early in fertilized eggs, suggesting the participation of this immune-related gene in the antimicrobial defenses during shrimp development.

  15. In vivo effects and interactions of recombinant interleukin 1 and tumor-necrosis factor in radioprotection and induction of fibrinogen. Scientific report

    SciTech Connect

    Neta, R.

    1988-01-01

    Although interleukin 1 (IL-1) and tumor necrosis factor (TNF) are both produced by stimulated macrophage-monocytes, they are molecularly distinct, act via separate receptors, but show striking resemblance in their biological activity. Both cytokines are pyrogenic, induce colony-stimulating factor and acute-phase proteins, activate neutrophils, reduce cytochrome P-450 functions, and inhibit lipoprotein lipase. Furthermore, IL-1 and TNF have been reported to induce the release of one another. Because of this mutual induction, the relative contribution of IL-1 or TNF to the induction of a given activity becomes difficult to establish. In an attempt to determine whether these two cytokines act independently, the effect of administrating them separately or in combination is compared on the radioprotection and on the induction of an acute-phase reactant - fibrinogen. IL-1 and TNF have synergistic effects on radioprotection and on the levels of circulating fibrinogen.

  16. Control of Fibrinogen Assembly by Changing a Polarity of Surfaces

    NASA Astrophysics Data System (ADS)

    Koo, Jaseung; Liu, Ying; Snow, Sara; Rambhia, Pooja; Koga, Tadanori; Rafailovich, Miriam; Galanakis, Dennis

    2009-03-01

    Thrombogenesis causes various problems associated with an interruption in the blood flow (e.g., myocardial and cerebral infarction), and a hindrance to use of blood-contact vascular biomaterials (e.g., hemodialysis and cardiopulmonary bypass) with long-term patency since undesired adsorption of blood components occurs on vessels or biomaterials, such as surface-induced thrombosis. we showed that this clotting procedure can be occurred on hydrophobic polymeric surfaces without thrombin cleavage. However, the fibrinogen fibers were not formed on the polar surface such as spun-cast polymer film with pyridine and phenol groups. We also found that αC domains play an important role in initiation of polymerization on surface. Therefore, molecular association was inhibited on the polar surfaces due to confinement of αC chains on the surfaces. These findings were directly applied to stent surface modification. The commercial stent consist of Co-Cr alloy forms undesired fiber formation. However, PS-r-PVPh (13% phenol) coated stent surfaces completely prevent fiber formation.

  17. Homocysteine, circulating vascular cell adhesion molecule and carotid atherosclerosis in postmenopausal vegetarian women and omnivores.

    PubMed

    Su, Ta-Chen; Jeng, Jiann-Shing; Wang, Jung-Der; Torng, Pao-Ling; Chang, Sue-Joan; Chen, Chen-Fang; Liau, Chiau-Suong

    2006-02-01

    Since the adoption of vegetarian diets as a healthy lifestyle has become popular, the cardiovascular effects of long-term vegetarianism need to be explored. The present study aimed to compare the presence and severity of carotid atherosclerosis (CA), and the blood levels of Vitamin B12, homocysteine (Hcy) and soluble vascular cell adhesion molecule-1 (sVCAM-1) between 57 healthy postmenopausal vegetarians and 61 age-matched omnivores. Carotid atherosclerosis, as measured by ultrasound, was found to be of no significant difference between the two groups. Yet, fasting blood glucose, low-density lipoprotein cholesterol, and Vitamin B12 were significantly lower, while Hcy and sVCAM-1 were higher in the vegetarians as comparing with the omnivores. Multivariate regression analysis showed that the level of Vitamin B12 was negatively associated with the level of Hcy. Vegetarianism itself and Hcy level were significantly associated with sVCAM-1 level in univariate analysis; however, after adjustment for covariates, we identified age but not vegetarianism as the determinant of sVCAM-1 level. Multiple linear regression analysis identified age and systolic blood pressure, but not vegetarianism, as determinants of common carotid artery IMT. In conclusion, there was no significant difference in CA between apparently healthy postmenopausal vegetarians and omnivores. The findings of elevated Hcy in vegetarians indicate the importance of prevention of Vitamin B12 deficiency.

  18. Effect of fibrinogen on blood coagulation detected by optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Xu, Xiangqun; Teng, Xiangshuai

    2015-05-01

    Our previous work demonstrated that an optical coherence tomography (OCT) technique and the parameter 1/e light penetration depth (d1/e) were able to characterize the whole blood coagulation process in contrast to existing optical tests that are performed on plasma samples. To evaluate the feasibility of the technique for quantifying the effect of fibrinogen (Fbg) on blood coagulation, a dynamic study of d1/e of blood in various Fbg concentrations was performed in static state. Two groups of blood samples of hematocrit (HCT) in 35, 45, and 55% were reconstituted of red blood cells with: 1) treated plasma with its intrinsic Fbg removed and commercial Fbg added (0-8 g L-1) and 2) native plasma with commercial Fbg added (0-8 g L-1). The results revealed a typical behavior due to coagulation induced by calcium ions and the clotting time is Fbg concentration-dependent. The clotting time was decreased by the increasing amount of Fbg in both groups. Besides, the blood of lower HCT with various levels of Fbg took shorter time to coagulate than that of higher HCT. Consequently, the OCT method is a useful and promising tool for the detection of blood-coagulation processes induced with different Fbg levels.

  19. Effect of fibrinogen on blood coagulation detected by optical coherence tomography.

    PubMed

    Xu, Xiangqun; Teng, Xiangshuai

    2015-05-21

    Our previous work demonstrated that an optical coherence tomography (OCT) technique and the parameter 1/e light penetration depth (d1/e) were able to characterize the whole blood coagulation process in contrast to existing optical tests that are performed on plasma samples. To evaluate the feasibility of the technique for quantifying the effect of fibrinogen (Fbg) on blood coagulation, a dynamic study of d1/e of blood in various Fbg concentrations was performed in static state. Two groups of blood samples of hematocrit (HCT) in 35, 45, and 55% were reconstituted of red blood cells with: 1) treated plasma with its intrinsic Fbg removed and commercial Fbg added (0-8 g L(-1)); and 2) native plasma with commercial Fbg added (0-8 g L(-1)). The results revealed a typical behavior due to coagulation induced by calcium ions and the clotting time is Fbg concentration-dependent. The clotting time was decreased by the increasing amount of Fbg in both groups. Besides, the blood of lower HCT with various levels of Fbg took shorter time to coagulate than that of higher HCT. Consequently, the OCT method is a useful and promising tool for the detection of blood-coagulation processes induced with different Fbg levels.

  20. Fibrinogen-like protein 1, a hepatocyte derived protein is an acute phase reactant

    SciTech Connect

    Liu Zhilin; Ukomadu, Chinweike

    2008-01-25

    Fibrinogen-like protein 1 (FGL1) is a hepatocyte derived protein that is upregulated in regenerating rodent livers following partial hepatectomy. It has been implicated as a mitogen for liver cell proliferation. In this study, we show that recombinant human IL-6 induces FGL1 expression in Hep G2 cells in a pattern similar to those of acute phase reactants. Following induction of acute inflammation in rats by subcutaneous injection of turpentine oil, serum FGL1 levels are also enhanced. Although, a recent report suggests that FGL1 associates almost exclusively with the fibrin matrix, we report here that approximately 20% of the total plasma FGL1 remains free. The enhancement of FGL1 levels in vitro by IL-6 and its induction after turpentine oil injection suggest that it is an acute phase reactant. Its presence in bound and free forms in the blood also implies biological roles that extend beyond the proposed autocrine effect it has on hepatocytes during regeneration.

  1. A turn-on fluorescent sensor for the discrimination of cystein from homocystein and glutathione.

    PubMed

    Niu, Li-Ya; Guan, Ying-Shi; Chen, Yu-Zhe; Wu, Li-Zhu; Tung, Chen-Ho; Yang, Qing-Zheng

    2013-02-14

    We report a turn-on fluorescent sensor based on nitrothiophenolate boron dipyrromethene (BODIPY) derivatives for the discrimination of cystein (Cys) from homocystein (Hcy) and glutathione (GSH). The sensor was applied for detection of Cys in living cells. PMID:23295243

  2. A turn-on fluorescent sensor for the discrimination of cystein from homocystein and glutathione.

    PubMed

    Niu, Li-Ya; Guan, Ying-Shi; Chen, Yu-Zhe; Wu, Li-Zhu; Tung, Chen-Ho; Yang, Qing-Zheng

    2013-02-14

    We report a turn-on fluorescent sensor based on nitrothiophenolate boron dipyrromethene (BODIPY) derivatives for the discrimination of cystein (Cys) from homocystein (Hcy) and glutathione (GSH). The sensor was applied for detection of Cys in living cells.

  3. Identification of a 58-kilodalton cell surface fibrinogen-binding mannoprotein from Candida albicans.

    PubMed Central

    Casanova, M; Lopez-Ribot, J L; Monteagudo, C; Llombart-Bosch, A; Sentandreu, R; Martinez, J P

    1992-01-01

    Treatment of both yeast (blastoconidia) and hyphal (blastoconidia with germ tubes) cells of Candida albicans with beta-mercaptoethanol (beta ME) releases a complex array of cell wall-bound proteins and glycoproteins. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western immunoblotting with fibrinogen-anti-fibrinogen antibody allowed the identification of a 58-kDa mannoprotein (mp58) in both extracts which specifically interacts with human fibrinogen. Treatment of intact cells with low concentrations of beta-glucanase (Zymolyase 20T) for short periods or with beta ME abolished or significantly reduced binding of fibrinogen. A rabbit polyclonal antiserum was raised against the purified mp58 species released by beta ME from germinated blastoconidia (PAb anti-mp58). By Western blotting, the antiserum cross-reacted with the homologous 58-kDa fibrinogen-binding mannoprotein present in beta ME extracts from blastoconidia, and by indirect immunofluorescence, the antiserum labelled both yeast cells and hyphae, yet reactivity was found primarily on the cell surface of filamentous forms. Immunostaining of human infected tissue sections with PAb anti-mp58 showed that the mp58 species is also expressed in vivo; in this case, the species is in the forms of both yeast and hyphal elements similarly labelled by the antiserum. Purified immunoglobulin G fraction from the antiserum did not alter the binding of fibrinogen as determined by a modified enzyme-linked immunosorbent assay and Western blotting. The N- and O-glycosidically linked carbohydrates represent 18 to 20% and 3 to 4%, respectively, of the molecular mass of the mp58. O-linked sugar residues may be involved in the interaction of the molecule with fibrinogen. Images PMID:1398933

  4. Identification of a 58-kilodalton cell surface fibrinogen-binding mannoprotein from Candida albicans.

    PubMed

    Casanova, M; Lopez-Ribot, J L; Monteagudo, C; Llombart-Bosch, A; Sentandreu, R; Martinez, J P

    1992-10-01

    Treatment of both yeast (blastoconidia) and hyphal (blastoconidia with germ tubes) cells of Candida albicans with beta-mercaptoethanol (beta ME) releases a complex array of cell wall-bound proteins and glycoproteins. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western immunoblotting with fibrinogen-anti-fibrinogen antibody allowed the identification of a 58-kDa mannoprotein (mp58) in both extracts which specifically interacts with human fibrinogen. Treatment of intact cells with low concentrations of beta-glucanase (Zymolyase 20T) for short periods or with beta ME abolished or significantly reduced binding of fibrinogen. A rabbit polyclonal antiserum was raised against the purified mp58 species released by beta ME from germinated blastoconidia (PAb anti-mp58). By Western blotting, the antiserum cross-reacted with the homologous 58-kDa fibrinogen-binding mannoprotein present in beta ME extracts from blastoconidia, and by indirect immunofluorescence, the antiserum labelled both yeast cells and hyphae, yet reactivity was found primarily on the cell surface of filamentous forms. Immunostaining of human infected tissue sections with PAb anti-mp58 showed that the mp58 species is also expressed in vivo; in this case, the species is in the forms of both yeast and hyphal elements similarly labelled by the antiserum. Purified immunoglobulin G fraction from the antiserum did not alter the binding of fibrinogen as determined by a modified enzyme-linked immunosorbent assay and Western blotting. The N- and O-glycosidically linked carbohydrates represent 18 to 20% and 3 to 4%, respectively, of the molecular mass of the mp58. O-linked sugar residues may be involved in the interaction of the molecule with fibrinogen.

  5. Reduced Transfusion During OLT by POC Coagulation Management and TEG Functional Fibrinogen: A Retrospective Observational Study

    PubMed Central

    De Pietri, Lesley; Ragusa, Francesca; Deleuterio, Annalisa; Begliomini, Bruno; Serra, Valentina

    2016-01-01

    Background Patients undergoing orthotopic liver transplantation are at high risk of bleeding complications. Several Authors have shown that thromboelastography (TEG)-based coagulation management and the administration of fibrinogen concentrate reduce the need for blood transfusion. Methods We conducted a single-center, retrospective cohort observational study (Modena Polyclinic, Italy) on 386 consecutive patients undergoing liver transplantation. We assessed the impact on resource consumption and patient survival after the introduction of a new TEG-based transfusion algorithm, requiring also the introduction of the fibrinogen functional thromboelastography test and a maximum amplitude of functional fibrinogen thromboelastography transfusion cutoff (7 mm) to direct in administering fibrinogen (2012-2014, n = 118) compared with a purely TEG-based algorithm previously used (2005-2011, n = 268). Results After 2012, there was a significant decrease in the use of homologous blood (1502 ± 1376 vs 794 ± 717 mL, P < 0.001), fresh frozen plasma (537 ± 798 vs 98 ± 375 mL, P < 0.001), and platelets (158 ± 280 vs 75 ± 148 mL, P < 0.005), whereas the use of fibrinogen increased (0.1 ± 0.5 vs 1.4 ± 1.8 g, P < 0.001). There were no significant differences in 30-day and 6-month survival between the 2 groups. Conclusions The implementation of a new coagulation management method featuring the addition of the fibrinogen functional thromboelastography test to the TEG test according to an algorithm which provides for the administration of fibrinogen has helped in reducing the need for transfusion in patients undergoing liver transplantation with no impact on their survival. PMID:27500243

  6. Oral contraceptives did not affect biochemical folate indexes and homocysteine concentrations in adolescent females.

    PubMed

    Green, T J; Houghton, L A; Donovan, U; Gibson, R S; O'Connor, D L

    1998-01-01

    The impact of oral contraceptive (OC) use, smoking, and alcohol drinking on biochemical indexes of folate and vitamin B-12 was investigated in 229 adolescents 14-20 years old recruited from advertisements in Ontario, Canada. Subjects completed a life-style questionnaire and a 3-day, weighed food record, followed by overnight fasting and the collection of blood samples. Of the 48 participants (21%) who were OC users, 30 had used the pill for more than 12 months. Only 37 adolescents (16%) smoked, but 94 (60%) had consumed alcohol in the month preceding the study. Median daily intake of folate and vitamin B-12 (including intake from supplements) was 215 mcg and 1.9 mcg, respectively. OC use, smoking, and alcohol consumption were not significantly associated with lower serum or red blood cell folate levels, after controlling for folate intake. Serum homocysteine levels were not correlated with smoking or OC use, but were 13% higher among alcohol drinkers than nondrinkers. Finally, although smoking and alcohol use were not associated with serum B-12 levels, OC use was linked with an estimated 33% lower serum B-12 level than was nonuse. These findings fail to validate concerns that OC use has a negative impact on the folate status of adolescent females, but suggest a need to improve the dietary folate intake of young women who smoke.

  7. Total serum homocysteine as an indicator of vitamin B12 and folate status

    SciTech Connect

    Chu, R.C.; Hall, C.A.

    1988-10-01

    Presented is a modification of an assay for total serum homocysteine (Hcy) in which the Hcy plus radioactive adenosine is converted enzymatically to labeled S-adenosylhomocysteine (AdoHcy). The modifications included a commerical source for the AdoHcy hydrolase, adenosine labeled with either /sup 14/C or /sup 3/H, and separation of the AdoHcy by thin layer chromatography. The assay was sensitive to 25 pmol. Hcy levels in sera from 18 controls ranged from 6.9 to 12.1 mumol/L with a mean of 9.1 and a SD of 1.5 mumol/L. The total serum Hcy was increased in vitamin B12 and folate deficiency. The level was high in congenital defects of vitamin B12 metabolism, blocking the methylation of Hcy regardless of the serum vitamin B12 levels, but was normal in the absence of tissue deficiency even if the serum vitamin B12 levels were low. The procedure has been found practical in two years of use and requires only 0.1 mL of serum.

  8. ACP Broadsheet No 152: March 1998. Clinical implications of plasma homocysteine measurement in cardiovascular disease.

    PubMed Central

    Still, R A; McDowell, I F

    1998-01-01

    Plasma homocysteine is emerging as an important risk factor for cardiovascular disease. Measurement in clinical laboratories is feasible by several techniques, including HPLC. Of particular importance is the potential for treatment by dietary modification and vitamin supplements, particularly folic acid. The outcome of vitamin intervention on cardiovascular events is awaited with interest. If the role of homocysteine is confirmed then it may rival cholesterol in importance as a cardiovascular risk factor. Images PMID:9659257

  9. Stroke: roles of B vitamins, homocysteine and antioxidants.

    PubMed

    Sánchez-Moreno, Concepción; Jiménez-Escrig, Antonio; Martín, Antonio

    2009-06-01

    In the present review concerning stroke, we evaluate the roles of B vitamins, homocysteine and antioxidant vitamins. Stroke is a leading cause of death in developed countries. However, current therapeutic strategies for stroke have been largely unsuccessful. Several studies have reported important benefits on reducing the risk of stroke and improving the post-stroke-associated functional declines in patients who ate foods rich in micronutrients, including B vitamins and antioxidant vitamins E and C. Folic acid, vitamin B6 and vitamin B12 are all cofactors in homocysteine metabolism. Growing interest has been paid to hyperhomocysteinaemia as a risk factor for CVD. Hyperhomocysteinaemia has been linked to inadequate intake of vitamins, particularly to B-group vitamins and therefore may be amenable to nutritional intervention. Hence, poor dietary intake of folate, vitamin B6 and vitamin B12 are associated with increased risk of stroke. Elevated consumption of fruits and vegetables appears to protect against stroke. Antioxidant nutrients have important roles in cell function and have been implicated in processes associated with ageing, including vascular, inflammatory and neurological damage. Plasma vitamin E and C concentrations may serve as a biological marker of lifestyle or other factors associated with reduced stroke risk and may be useful in identifying those at high risk of stroke. After reviewing the observational and intervention studies, there is an incomplete understanding of mechanisms and some conflicting findings; therefore the available evidence is insufficient to recommend the routine use of B vitamins, vitamin E and vitamin C for the prevention of stroke. A better understanding of mechanisms, along with well-designed controlled clinical trials will allow further progress in this area.

  10. Fibrinogen Induces Alterations of Endothelial Cell Tight Junction Proteins

    PubMed Central

    PATIBANDLA, PHANI K.; TYAGI, NEETU; DEAN, WILLIAM L.; TYAGI, SURESH C.; ROBERTS, ANDREW M.; LOMINADZE, DAVID

    2009-01-01

    We previously showed that an elevated content of fibrinogen (Fg) increased formation of filamentous actin and enhanced endothelial layer permeability. In the present work we tested the hypothesis that Fg binding to endothelial cells (ECs) alters expression of actin-associated endothelial tight junction proteins (TJP). Rat cardiac microvascular ECs were grown in gold plated chambers of an electrical cell-substrate impedance system, 8-well chambered, or in 12-well plates. Confluent ECs were treated with Fg (2 or 4 mg/ml), Fg (4 mg/ml) with mitogen-activated protein kinase (MEK) kinase inhibitors (PD98059 or U0126), Fg (4 mg/ml) with anti-ICAM-1 antibody or BQ788 (endothelin type B receptor blocker), endothelin-1, endothelin-1 with BQ788, or medium alone for 24 h. Fg induced a dose-dependent decrease in EC junction integrity as determined by transendothelial electrical resistance (TEER). Western blot analysis and RT-PCR data showed that the higher dose of Fg decreased the contents of TJPs, occludin, zona occluden-1 (ZO-1), and zona occluden-2 (ZO-2) in ECs. Fg-induced decreases in contents of the TJPs were blocked by PD98059, U0126, or anti-ICAM-1 antibody. While BQ788 inhibited endothelin-1-induced decrease in TEER, it did not affect Fg-induced decrease in TEER. These data suggest that Fg increases EC layer permeability via the MEK kinase signaling pathway by affecting occludin, ZO-1, and ZO-2, TJPs, which are bound to actin filaments. Therefore, increased binding of Fg to its major EC receptor, ICAM-1, during cardiovascular diseases may increase microvascular permeability by altering the content and possibly subcellular localization of endothelial TJPs. PMID:19507189

  11. Consumption of wheat aleurone-rich foods increases fasting plasma betaine and modestly decreases fasting homocysteine and LDL-cholesterol in adults.

    PubMed

    Price, Ruth K; Keaveney, Edel M; Hamill, Lesley L; Wallace, Julie M W; Ward, Mary; Ueland, Per M; McNulty, Helene; Strain, J J; Parker, Michael J; Welch, Robert W

    2010-12-01

    There is strong evidence that whole-grain foods protect against heart disease. Although underlying mechanisms and components are unclear, betaine, found at high levels in wheat aleurone, may play a role. We evaluated the effects of a diet high in wheat aleurone on plasma betaine and related measures. In a parallel, single-blinded intervention study, 79 healthy participants (aged 45-65 y, BMI ≥ 25 kg/m(2)) incorporated either aleurone-rich cereal products (27 g/d aleurone) or control products balanced for fiber and macronutrients into their habitual diets for 4 wk. Fasting blood samples were taken at baseline and postintervention (4 wk) from participants. Compared with the control, the aleurone products provided an additional 279 mg/d betaine and resulted in higher plasma betaine (P < 0.001; intervention effect size: 5.2 μmol/L) and lower plasma total homocysteine (tHcy) (P = 0.010; -0.7 μmol/L). Plasma dimethylglycine and methionine, which are products of betaine-mediated homocysteine remethylation, were also higher (P < 0.001; P = 0.027) relative to control. There were no significant effects on plasma choline or B vitamins (folate, riboflavin, and vitamin B-6). However, LDL cholesterol was lower than in the control group (P = 0.037). We conclude that incorporating aleurone-rich products into the habitual diet for 4 wk significantly increases plasma betaine concentrations and lowers tHcy, which is attributable to enhanced betaine-homocysteine methyltransferase-mediated remethylation of homocysteine. Although this supports a role for betaine in the protective effects of whole grains, concomitant decreases in LDL suggest more than one component or mechanism may be responsible.

  12. Homocysteine and the C677T Gene Polymorphism of Its Key Metabolic Enzyme MTHFR Are Risk Factors of Early Renal Damage in Hypertension in a Chinese Han Population.

    PubMed

    Yun, Lin; Xu, Rui; Li, Guohua; Yao, Yucai; Li, Jiamin; Cong, Dehong; Xu, Xingshun; Zhang, Lihua

    2015-12-01

    The combined hyperhomocysteinemia condition is a feature of the Chinese hypertensive population. This study used the case-control method to investigate the association between plasma homocysteine and the C677T gene polymorphism of its key metabolic enzyme, 5, 10-methylenetetrahydrofolate reductase (MTHFR), and early renal damage in a hypertensive Chinese Han population.A total of 379 adult essential hypertensive patients were selected as the study subjects. The personal information, clinical indicators, and the C677T gene polymorphism of MTHFR were texted. This study used the urine microalbumin/urine creatinine ratio (UACR) as a grouping basis: the hypertension without renal damage group (NRD group) and the hypertension combined with early renal damage group (ERD group).Early renal damage in the Chinese hypertensive population was associated with body weight, systolic pressure, diastolic pressure, urea nitrogen, serum creatinine, cystatin C, uric acid, aldosterone, and glomerular filtration rate. The homocysteine level and the UACR in the TT genotype group were higher than those in the CC genotype group. The binary logistic regression analysis results showed that after sex and age were adjusted, the MTHFR C677T gene polymorphism was correlated with early renal damage in hypertension in both the recessive model and in the additive model.Plasma homocysteine and the C677T gene polymorphism of its key metabolic enzyme MTHFR might be independent risk factors of early renal damage in the hypertensive Chinese Han population.

  13. The diagnostic value of serum homocysteine concentration as a risk factor for coronary artery disease.

    PubMed

    Dierkes, J; Bissé, E; Nauck, M; Orth, M; Mayer, H; Luley, C; Wieland, H

    1998-06-01

    Hyperhomocysteinemia is now regarded as an established risk factor for coronary artery disease and is present frequently in the general population. However, the diagnostic value of this risk factor relative to others has only occasionally been investigated. We compared the diagnostic value of classic risk factors and of homocysteine in a retrospective case-control study in 191 cases with angiographically established coronary artery disease and 231 healthy controls. Life style habits were assessed by a detailed questionnaire. Laboratory parameters including lipoproteins and blood lipids, homocysteine, folate, and vitamin B12 were measured and their diagnostic value compared with each other by use of receiver-operator characteristic analysis. Comparison of the receiver-operator characteristic curves revealed that homocysteine significantly discriminated between cases and control subjects. High-density-lipoprotein cholesterol, triglycerides and non-esterified fatty acids also had an area under the curve significantly different from 0.5 (the area under the curve representing no discrimination). Homocysteine was weakly related to folate, vitamin B12, age and serum creatinine concentration. We conclude that hyperhomocysteinemia is at least as important as conventional risk factors for coronary artery disease and that receiver operator characteristic analysis of homocysteine is suitable to determine patients at the highest risk for coronary artery disease. Clinical trials testing the effect of homocysteine lowering by vitamin supplementation in the prevention of coronary artery disease are needed.

  14. Existence of molten globule state in homocysteine-induced protein covalent modifications.

    PubMed

    Kumar, Tarun; Sharma, Gurumayum Suraj; Singh, Laishram Rajendrakumar

    2014-01-01

    Homocysteine thiolactone is a toxic metabolite produced from homocysteine by amino-acyl t-RNA synthetase in error editing reaction. The basic cause of toxicity of homocysteine thiolactone is believed to be due to the adduct formation with lysine residues (known as protein N-homocysteinylation) leading to protein aggregation and loss of enzyme function. There was no data available until now that showed the effect of homocysteine thiolactone on the native state structural changes that led to aggregate formation. In the present study we have investigated the time dependent structural changes due to homocysteine thiolactone induced modifications on three different proteins having different physico-chemical properties (cytochrome-c, lysozyme and alpha lactalbumin). We discovered that N-homocysteinylation leads to the formation of molten globule state--an important protein folding intermediate in the protein folding pathway. We also found that the formation of the molten globule state might be responsible for the appearance of aggregate formation. The study indicates the importance of protein folding intermediate state in eliciting the homocysteine thiolactone toxicity. PMID:25405350

  15. Fibrinogen surface distribution correlates to platelet adhesion pattern on fluorinated surface-modified polyetherurethane.

    PubMed

    Massa, T M; Yang, M L; Ho, J Y C; Brash, J L; Santerre, J P

    2005-12-01

    In previous work, it had been shown that platelet adhesion could be reduced by fluorinating surfaces with oligomeric fluoropolymers, referred to as surface-modifying macromolecules (SMMs). In the current study, two in vitro blood-contacting experiments were carried out on a polyetherurethane modified with three different SMMs in order to determine if altered platelet adhesion levels could be related to the pattern of adsorbed protein and more specifically to the manner in which fibrinogen (Fg) distribution occurs at the surface. In the first experiment, the materials were placed in whole human blood and the adherent platelets were viewed with high-resolution scanning electron microscopy (SEM). In a second experiment, the materials were incubated with human plasma with the absence of platelets. The plasma contained 5% fluorescent-Fg. The materials were then viewed with a fluorescence microscope and images were collected to define the distribution of high-density fluorescent-Fg areas. The SEM and fluorescent-Fg images were imported to Image Pro Plus imaging software to measure the area, length and circularity and a bivariate correlation test was conducted between the two sets of data. For area and length morphology parameters, there were high and significant correlations (r > 0.9, p < 0.05) between the platelets and Fg aggregates. The data suggest that the Fg distribution may serve as a predictor of platelet morphology/activation and provides insight into the non-thrombogenic character of biomaterials containing the fluorinated SMMs. PMID:16026826

  16. Fibrinogen β–derived Bβ15-42 peptide protects against kidney ischemia/ reperfusion injury

    PubMed Central

    Krishnamoorthy, Aparna; Ajay, Amrendra Kumar; Hoffmann, Dana; Kim, Tae-Min; Ramirez, Victoria; Campanholle, Gabriela; Bobadilla, Norma A.; Waikar, Sushrut S.

    2011-01-01

    Ischemia/reperfusion (I/R) injury in the kidney is a major cause of acute kidney injury (AKI) in humans and is associated with significantly high mortality. To identify genes that modulate kidney injury and repair, we conducted genome-wide expression analysis in the rat kidneys after I/R and found that the mRNA levels of fibrinogen (Fg)α, Fgβ, and Fgγ chains significantly increase in the kidney and remain elevated throughout the regeneration process. Cellular characterization of Fgα and Fgγ chain immunoreactive proteins shows a predominant expression in renal tubular cells and the localization of immunoreactive Fgβ chain protein is primarily in the renal interstitium in healthy and regenerating kidney. We also show that urinary excretion of Fg is massively increased after kidney damage and is capable of distinguishing human patients with acute or chronic kidney injury (n = 25) from healthy volunteers (n = 25) with high sensitivity and specificity (area under the receiver operating characteristic of 0.98). Furthermore, we demonstrate that Fgβ-derived Bβ15-42 peptide administration protects mice from I/R-induced kidney injury by aiding in epithelial cell proliferation and tissue repair. Given that kidney regeneration is a major determinant of outcome for patients with kidney damage, these results provide new opportunities for the use of Fg in diagnosis, prevention, and therapeutic interventions in kidney disease. PMID:21685370

  17. Homocysteine Aggravates Cortical Neural Cell Injury through Neuronal Autophagy Overactivation following Rat Cerebral Ischemia-Reperfusion

    PubMed Central

    Zhao, Yaqian; Huang, Guowei; Chen, Shuang; Gou, Yun; Dong, Zhiping; Zhang, Xumei

    2016-01-01

    Elevated homocysteine (Hcy) levels have been reported to be involved in neurotoxicity after ischemic stroke. However, the underlying mechanisms remain incompletely understood to date. In the current study, we hypothesized that neuronal autophagy activation may be involved in the toxic effect of Hcy on cortical neurons following cerebral ischemia. Brain cell injury was determined by hematoxylin-eosin (HE) staining and TdT-mediated dUTP Nick-End Labeling (TUNEL) staining. The level and localization of autophagy were detected by transmission electron microscopy, western blot and immunofluorescence double labeling. The oxidative DNA damage was revealed by immunofluorescence of 8-Hydroxy-2′-deoxyguanosine (8-OHdG). Hcy treatment aggravated neuronal cell death, significantly increased the formation of autophagosomes and the expression of LC3B and Beclin-1 in the brain cortex after middle cerebral artery occlusion-reperfusion (MCAO). Immunofluorescence analysis of LC3B and Beclin-1 distribution indicated that their expression occurred mainly in neurons (NeuN-positive) and hardly in astrocytes (GFAP-positive). 8-OHdG expression was also increased in the ischemic cortex of Hcy-treated animals. Conversely, LC3B and Beclin-1 overexpression and autophagosome accumulation caused by Hcy were partially blocked by the autophagy inhibitor 3-methyladenine (3-MA). Hcy administration enhanced neuronal autophagy, which contributes to cell death following cerebral ischemia. The oxidative damage-mediated autophagy may be a molecular mechanism underlying neuronal cell toxicity of elevated Hcy level. PMID:27455253

  18. Platelet morphologic changes and fibrinogen receptor localization. Initial responses in ADP-activated human platelets.

    PubMed

    Hensler, M E; Frojmovic, M; Taylor, R G; Hantgan, R R; Lewis, J C

    1992-09-01

    Platelet exposure to agonists results in rapid morphologic changes paralleled by fibrinogen binding and platelet aggregation. The current study used standardized stereology in conjunction with immunogold electron microscopy to correlate the initial morphologic changes with fibrinogen receptor localization on the surfaces of ADP-activated human platelets. A 45% increase in platelet circumference was observed after 3 seconds of activation (P = 0.001). Virtually all of this increase was due to a 13-fold increase in projection membrane, and the projections observed by stereo microscopy at this time were mostly blunt. Both blunt and long projections also accounted for the increase in platelet-platelet contacts at 10 seconds of activation. Immunogold electron microscopy using the monoclonal antibodies P2 and AP-2 against the fibrinogen receptor, glycoprotein IIb/IIIa (GP IIb/IIIa), showed relatively equivalent immunogold densities on projections compared with cell body during 30 seconds of activation. The activation-dependent anti-GP IIb/IIIa monoclonal antibody, 7E3, showed an immunogold density 37% greater on projections compared with cell body (P = 0.0001). Colocalization studies using 7E3 with a polyclonal antifibrinogen antibody showed bound fibrinogen in close proximity to the GP IIb/IIIa localized by 7E3 on projections. These studies support an important role for platelet projections during the earliest stages of fibrinogen binding and ADP-induced aggregation.

  19. Fibrinogen {alpha} genes: Conservation of bipartite transcripts and carboxy-terminal-extended {alpha} subunits in vertebrates

    SciTech Connect

    Fu, Y.; Cao, Y.; Hertzberg, K.M.; Grieninger, G.

    1995-11-01

    All three well-studied subunits of the clotting protein fibrinogen ({alpha}, {beta}, {gamma}) share N-terminal structural homologies, but until recently only the {beta} and {gamma} chains were recognized as having similar globular C-termini. With the discovery of an extra exon in the human fibrinogen {alpha} gene (exon VI), a minor form of the {alpha} subunit ({alpha}{sub E}) with an extended {beta}- and {gamma}-like C-terminus has been identified. In the present study, the polymerase chain reaction has been used to identify sequences that encode counterparts to {alpha}{sub E} in chicken, rabbit, rat, and baboon. The basic six-exon structure of the fibrinogen {alpha} genes is shown to be conserved among mammals and birds, as are the intron positions. Bipartite transcripts - still bearing an intron prior to the last exon - are found among the products of the various vertebrate fibrinogen {alpha} genes. The last exon represents the largest conserved segment of the gene and, in each species examined, encodes exactly 236 amino acids. The C-termini of these {alpha}{sub E} chains align without a single gap and are between 76 and 99% identical. Since the exon VI-encoded domain of {alpha}{sub E} is as well conserved as the corresponding regions of the {beta} and {gamma} chains, it follows that it is equally important and that {alpha}{sub E}-fibrinogen plays a vital, if as-yet unrecognized physiological role. 21 refs., 7 figs., 1 tab.

  20. ATR-FTIR measurements of albumin and fibrinogen adsorption: Inert versus calcium phosphate ceramics.

    PubMed

    Boix, Marcel; Eslava, Salvador; Costa Machado, Gil; Gosselin, Emmanuel; Ni, Na; Saiz, Eduardo; De Coninck, Joël

    2015-11-01

    Arthritis, bone fracture, bone tumors and other musculoskeletal diseases affect millions of people across the world. Nowadays, inert and bioactive ceramics are used as bone substitutes or for bone regeneration. Their bioactivity is very much dictated by the way proteins adsorb on their surface. In this work, we compared the adsorption of albumin and fibrinogen on inert and calcium phosphates ceramics (CaPs) using attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) to follow in situ protein adsorption on these materials. To this effect, we developed a sol-gel technique to control the surface chemistry of an ATR-FTIR detector. Hydroxyapatite adsorbed more albumin and β-tricalcium phosphate adsorbed more fibrinogen. Biphasic calcium phosphate presented the lowest adsorption among CaP for both proteins, illustrating the effect of surface heterogeneities. Inert ceramics adsorbed a lower amount of both proteins compared with bioactive ceramics. A significant change was observed in the conformation of the adsorbed protein versus the surface chemistry. Hydroxyapatite produced a larger loss of α-helix structure on albumin and biphasic calcium phosphate reduced β-sheet percentage on fibrinogen. Inert ceramics produced large α-helix loss on albumin and presented weak interaction with fibrinogen. Zirconia did not adsorb albumin and titanium dioxide promoted huge denaturalization of fibrinogen.

  1. Fibrinogen: a possible link between social class and coronary heart disease.

    PubMed Central

    Markowe, H L; Marmot, M G; Shipley, M J; Bulpitt, C J; Meade, T W; Stirling, Y; Vickers, M V; Semmence, A

    1985-01-01

    Mortality from coronary heart disease in civil servants in the lowest grade of employment has been found to be about three times that of men in the highest grade of employment. As part of an investigation of this finding several haemostatic variables were measured in a sample of 29 men in lower grades of employment and 45 men in higher grades. There was a significant difference in plasma fibrinogen concentrations between men in lower grades of employment and those in higher grades (mean 3.39 g/l v 2.95 g/l, respectively; p less than 0.01) but not in other haemostatic variables. Multiple regression analyses showed significant independent associations of fibrinogen concentration with smoking (p less than 0.05) and grade of employment (p less than 0.05). The size of the observed difference between the grades of employment was similar to that between those dying of coronary heart disease or surviving during longitudinal study; it may therefore be an important part of the mechanism underlying social class differences in coronary heart disease. The statistical relation between fibrinogen concentrations and other characteristics that may be concerned in the aetiology of coronary heart disease was examined. A summary measure of job stress was significantly related to fibrinogen concentration (p less than 0.01) and made a substantial contribution to explaining the differences between grades of employment. Behaviour type and a score of physical activity were not significantly related to fibrinogen concentration. PMID:3933646

  2. Spatially selective surface platforms for binding fibrinogen prepared by particle lithography with organosilanes

    PubMed Central

    Englade-Franklin, Lauren E.; Saner, ChaMarra K.; Garno, Jayne C.

    2013-01-01

    We introduce an approach based on particle lithography to prepare spatially selective surface platforms of organosilanes that are suitable for nanoscale studies of protein binding. Particle lithography was applied for patterning fibrinogen, a plasma protein that has a major role in the clotting cascade for blood coagulation and wound healing. Surface nanopatterns of mercaptosilanes were designed as sites for the attachment of fibrinogen within a protein-resistant matrix of 2-[methoxy(polyethyleneoxy)propyl] trichlorosilane (PEG-silane). Preparing site-selective surfaces was problematic in our studies, because of the self-reactive properties of PEG-organosilanes. Certain organosilanes presenting hydroxyl head groups will cross react to form mixed surface multi-layers. We developed a clever strategy with particle lithography using masks of silica mesospheres to protect small, discrete regions of the surface from cross reactions. Images acquired with atomic force microscopy (AFM) disclose that fibrinogen attached primarily to the surface areas presenting thiol head groups, which were surrounded by PEG-silane. The activity for binding anti-fibrinogen was further evaluated using ex situ AFM studies, confirming that after immobilization the fibrinogen nanopatterns retained capacity for binding immunoglobulin G. Studies with AFM provide advantages of achieving nanoscale resolution for detecting surface changes during steps of biochemical surface reactions, without requiring chemical modification of proteins or fluorescent labels. PMID:24427541

  3. Blood coagulation protein fibrinogen promotes autoimmunity and demyelination via chemokine release and antigen presentation

    PubMed Central

    Ryu, Jae Kyu; Petersen, Mark A.; Murray, Sara G.; Baeten, Kim M.; Meyer-Franke, Anke; Chan, Justin P.; Vagena, Eirini; Bedard, Catherine; Machado, Michael R.; Coronado, Pamela E. Rios; Prod'homme, Thomas; Charo, Israel F.; Lassmann, Hans; Degen, Jay L.; Zamvil, Scott S.; Akassoglou, Katerina

    2015-01-01

    Autoimmunity and macrophage recruitment into the central nervous system (CNS) are critical determinants of neuroinflammatory diseases. However, the mechanisms that drive immunological responses targeted to the CNS remain largely unknown. Here we show that fibrinogen, a central blood coagulation protein deposited in the CNS after blood–brain barrier disruption, induces encephalitogenic adaptive immune responses and peripheral macrophage recruitment into the CNS leading to demyelination. Fibrinogen stimulates a unique transcriptional signature in CD11b+ antigen-presenting cells inducing the recruitment and local CNS activation of myelin antigen-specific Th1 cells. Fibrinogen depletion reduces Th1 cells in the multiple sclerosis model, experimental autoimmune encephalomyelitis. Major histocompatibility complex (MHC) II-dependent antigen presentation, CXCL10- and CCL2-mediated recruitment of T cells and macrophages, respectively, are required for fibrinogen-induced encephalomyelitis. Inhibition of the fibrinogen receptor CD11b/CD18 protects from all immune and neuropathologic effects. Our results show that the final product of the coagulation cascade is a key determinant of CNS autoimmunity. PMID:26353940

  4. The fibrinogen gamma 10034C>T polymorphism is not associated with Peripheral Arterial Disease.

    PubMed

    Bahadori, Babak; Uitz, Elisabeth; Dehchamani, Dadbeh; Pilger, Ernst; Renner, Wilfried

    2010-10-01

    Conversion of fibrinogen to fibrin plays an essential role in hemostasis and results in stabilization of the fibrin clot. Fibrinogen consists of three pairs of non-identical polypeptide chains, encoded by different genes (fibrinogen alpha [FGA], fibrinogen beta [FGB] and fibrinogen gamma [FGG]). A functional single nucleotide polymorphism (SNP) in the 3' untranslated region of the FGG gene (FGG 10034C>T, rs2066865) has been associated with deep venous thrombosis and myocardial infarction. Aim of the present study was to analyze the role of this polymorphism in peripheral arterial disease (PAD). The study was designed as case-control study including 891 patients with documented PAD and 777 control subjects. FGG genotypes were determined by exonuclease (TaqMan) assays. FGG genotype frequencies were not significantly different between PAD patients (CC: 57.3%, CT: 36.7%, TT: 5.8%) and control subjects (CC: 60.9%, CT: 33.5%, TT 5.6%; p=0.35). In a multivariate logistic regression analysis including age, sex, smoking, diabetes, arterial hypertension and hypercholesterolemia, the FGG 10034 T variant was not significantly associated with the presence of PAD (Odds ratio 1.07, 95% confidence interval 0.84 - 1.37; p = 0.60). The FGG 10034C>T polymorphism was furthermore not associated with age at onset of PAD. We conclude that the thrombophilic FGG 10034 T gene variant does not contribute to the genetic susceptibility to PAD.

  5. Role of phosphoinositide 3-kinase in adhesion of platelets to fibrinogen stimulated by cancer procoagulant.

    PubMed

    Olas, B; Wachowicz, B; Mielicki, W P

    2001-11-01

    Cancer procoagulant, cysteine proteinase (CP; EC 3.4.22.26) activates factor X and functions in the absence of factor VII. CP may also change the platelet function. It induces an increase of platelet adhesion to collagen and fibrinogen. Using wortmannin--the inhibitor of phosphoinositide 3-kinase (PI 3-K)--we studied the role of this enzyme in the action of cancer procoagulant on blood platelet adhesion in vitro. Wortmannin (25, 50 and 100 nM, 30 min, 37 degrees C) caused a reduction of platelet adhesion to fibrinogen (P<0.01) when blood platelets were stimulated by both 0.2 U/ml thrombin (IC(50)approximately 75 nM) and by 1 microM ADP (IC(50)approximately 60 nM). We observed that after CP treatment the adhesion of thrombin-activated and ADP-stimulated platelets to fibrinogen was augmented. The potentiated by CP adhesion of activated platelets to fibrinogen was reduced after preincubation of platelets with wortmannin (50 nM, 30 min, 37 degrees C). We conclude that in adhesion of platelets to fibrinogen stimulated by CP PI 3-K take place.

  6. High-resolution visualization of fibrinogen molecules and fibrin fibers with atomic force microscopy.

    PubMed

    Yermolenko, Ivan S; Lishko, Valeryi K; Ugarova, Tatiana P; Magonov, Sergei N

    2011-02-14

    We report an atomic force microscopy (AFM) study of fibrinogen molecules and fibrin fibers with resolution previously achieved only in few electron microscopy images. Not only are all objects triads, but the peripheral D regions are resolved into the two subdomains, apparently corresponding to the βC and γC domains. The conformational analysis of a large population of fibrinogen molecules on mica revealed the two most energetically favorable conformations characterized by bending angles of ∼100 and 160 degrees. Computer modeling of the experimental images of fibrinogen molecules showed that the AFM patterns are in good agreement with the molecular dimensions and shapes detected by other methods. Imaging in different environments supports the expected hydration of the fibrinogen molecules in buffer, whereas imaging in humid air suggests the 2D spreading of fibrinogen on mica induced by an adsorbed water layer. Visualization of intact hydrated fibrin fibers showed cross-striations with an axial period of 24.0 ± 1.6 nm, in agreement with a pattern detected earlier with electron microscopy and small-angle X-ray diffraction. However, this order is clearly detected on the surface of thin fibers and becomes less discernible with the fiber's growth. This structural change is consistent with the proposal that thinner fibers are denser than thicker ones, that is, that the molecule packing decreases with the increasing of the fibers' diameter.

  7. Fibrinogen-induced perivascular microglial clustering is required for the development of axonal damage in neuroinflammation

    PubMed Central

    Davalos, Dimitrios; Kyu Ryu, Jae; Merlini, Mario; Baeten, Kim M.; Le Moan, Natacha; Petersen, Mark A.; Deerinck, Thomas J.; Smirnoff, Dimitri S.; Bedard, Catherine; Hakozaki, Hiroyuki; Gonias Murray, Sara; Ling, Jennie B.; Lassmann, Hans; Degen, Jay L.; Ellisman, Mark H.; Akassoglou, Katerina

    2012-01-01

    Blood-brain barrier disruption, microglial activation and neurodegeneration are hallmarks of multiple sclerosis. However, the initial triggers that activate innate immune responses and their role in axonal damage remain unknown. Here we show that the blood protein fibrinogen induces rapid microglial responses toward the vasculature and is required for axonal damage in neuroinflammation. Using in vivo two-photon microscopy, we demonstrate that microglia form perivascular clusters before myelin loss or paralysis onset and that, of the plasma proteins, fibrinogen specifically induces rapid and sustained microglial responses in vivo. Fibrinogen leakage correlates with areas of axonal damage and induces reactive oxygen species release in microglia. Blocking fibrin formation with anticoagulant treatment or genetically eliminating the fibrinogen binding motif recognized by the microglial integrin receptor CD11b/CD18 inhibits perivascular microglial clustering and axonal damage. Thus, early and progressive perivascular microglial clustering triggered by fibrinogen leakage upon blood-brain barrier disruption contributes to axonal damage in neuroinflammatory disease. PMID:23187627

  8. Homocysteine-NMDA receptor mediated activation of extracellular-signal regulated kinase leads to neuronal cell death

    PubMed Central

    Poddar, Ranjana; Paul, Surojit

    2009-01-01

    Hyper-homocysteinemia is an independent risk factor for stroke and neurological abnormalities. However the underlying cellular mechanisms by which elevated homocysteine can promote neuronal death is not clear. In the present study we have examined the role of NMDA receptor mediated activation of the extracellular-signal regulated mitogen activated protein (ERK MAP) kinase pathway in homocysteine-dependent neurotoxicity. The study demonstrates that in neurons L-homocysteine-induced cell death is mediated through activation of NMDA receptors. The study also shows that homocysteine-dependent NMDA receptor stimulation and resultant Ca2+ influx leads to rapid and sustained phosphorylation of ERK MAP kinase. Inhibition of ERK phosphorylation attenuates homocysteine mediated neuronal cell death thereby demonstrating that activation of ERK MAP kinase signaling pathway is an intermediate step that couples homocysteine mediated NMDA receptor stimulation to neuronal death. The findings also show that cAMP response-element binding protein (CREB), a pro-survival transcription factor and a downstream target of ERK, is only transiently activated following homocysteine exposure. The sustained activation of ERK but a transient activation of CREB together suggest that exposure to homocysteine initiates a feedback loop that shuts off CREB signaling without affecting ERK phosphorylation and thereby facilitates homocysteine mediated neurotoxicity. PMID:19508427

  9. Effects of traditional Chinese medicines on serum lipid profiles and homocysteine in the ovariectomized rats.

    PubMed

    Lee, Su-Chen; Chang, Shun-Jen; Tsai, Li-Yu

    2004-01-01

    To investigate the effects of the traditional Chinese medicines, kuei-lu-erh-hsien-chiao and chia-wei-hsiao-yao-san, on the cardiovascular systems of mimic menopausal rats, five groups were formed: group 1 (the control group) was given a sham operation and received distilled water, while groups 2, 3, 4 and 5 were ovariectomized and received distilled water, kuei-lu-erh-hsien-chiao, chia-wei-hsiao-yao-san and 17-beta-estradiol, respectively, for4 months. Our results demonstrated that the mean differences of the estrogen levels in groups 3 or 5 were significantly higher than those of group 2. These data suggest that there might be some estrogen-like substances in kuei-lu-erh-hsien-chiao. However, the function of these estrogen-like substances was unknown. The mean differences of the triglyceride (TG) levels, high-density lipoprotein cholesterol (HDL-C) levels, low-density lipoprotein cholesterol (LDL-C) levels, and the ratios of TC/HDL-C and LDL-C/HDL-C in groups 1, 3, 4 and 5 were not significantly different from those in group 2. The mean differences of the total cholesterol (TC) levels in group 5 were significantly higher than those in group 2 (p < 0.05), but no obvious difference of the TC levels was found between groups 2 and 4. Nevertheless, the mean differences of the homocysteine (Hcy) levels in groups 4 and 5 were statistically lower than those of group 2. Therefore, administration of chia-wei-hsiao-yao-san declines the Hcy levels in OVX rats and does not affect the TC levels in these animals. In conclusion, our results indicate that chia-wei-hsiao-yao-san shows a more profound effect than 17-beta-estradiol in the prevention of atherosclerosis in these OVX rats. PMID:15481644

  10. Mechanisms of fibrinogen-acebutolol interactions: Insights from DSC, CD and LS.

    PubMed

    Hassan, Natalia; Ruso, Juan M; Somasundaran, P

    2011-02-01

    The complex formed due to the interaction of the amphiphilic betablocker acebutolol with fibrinogen in a buffer solution (50mN glycine, pH of 8.5) has been investigated using a multipronged physicochemical approach. Differential scanning calorimetry measurements of the complexes have shown no reversibility of thermal denaturation as indicated by the three observed peaks and the opposite role that acebutolol plays in the folding different domains of the fibrinogen molecule and the stability of such domains. While circular dichroism measurements have revealed that interaction of acebutolol with fibrinogen affects the protein secondary structure to a different extent depending on the temperature and drug concentration, dynamic light scattering analysis showed evidence for protein aggregation mainly to tetramers and dimers.

  11. Nanoparticle-induced unfolding of fibrinogen promotes Mac-1 receptor activation and inflammation

    NASA Astrophysics Data System (ADS)

    Deng, Zhou J.; Liang, Mingtao; Monteiro, Michael; Toth, Istvan; Minchin, Rodney F.

    2011-01-01

    The chemical composition, size, shape and surface characteristics of nanoparticles affect the way proteins bind to these particles, and this in turn influences the way in which nanoparticles interact with cells and tissues. Nanomaterials bound with proteins can result in physiological and pathological changes, including macrophage uptake, blood coagulation, protein aggregation and complement activation, but the mechanisms that lead to these changes remain poorly understood. Here, we show that negatively charged poly(acrylic acid)-conjugated gold nanoparticles bind to and induce unfolding of fibrinogen, which promotes interaction with the integrin receptor, Mac-1. Activation of this receptor increases the NF-κB signalling pathway, resulting in the release of inflammatory cytokines. However, not all nanoparticles that bind to fibrinogen demonstrated this effect. Our results show that the binding of certain nanoparticles to fibrinogen in plasma offers an alternative mechanism to the more commonly described role of oxidative stress in the inflammatory response to nanomaterials.

  12. Leg scanning with radioisotope-labeled fibrinogen in patients undergoing hip surgery

    SciTech Connect

    LeMoine, J.R.; Moser, K.M.

    1980-05-01

    To establish whether radioisotope-labeled fibrinogen leg scanning is of value in the context of hip surgery, we propsectively studied 21 consectuvie patients undergoing either total hip replacement (14) or open repair of a hip fracture (seven) with leg scans, contrast phlebography, and ventilation and perfusion lung scans. We found that in eight patients (38%), venous thromboembolism developed postoperatively. Agreement between phlebographic and leg scanning results was excellent. In no patient as venous thrombosis limited to the thigh on the operated-on side, a vital consideration in application of fibrinogen leg scanning to this patient population. Two patients had lung scan changes indicative of embolism; both had thrombi extending into thigh veins. Leg scanning with radioisotope-labeled fibrinogen appears to be a useful method for monitoring patients undergoing hip surgery, if the upper three counting points on the operated-on side are excluded.

  13. Plasma homocysteine in adolescents depends on the interaction between methylenetetrahydrofolate reductase genotype, lipids and folate: a seroepidemiological study

    PubMed Central

    Gil-Prieto, Ruth; Hernández, Valentín; Cano, Beatriz; Oya, Manuel; Gil, Ángel

    2009-01-01

    Background Many publications link high homocysteine levels to cardiovascular disease. In Spain there is little information on the prevalence of hyperhomocysteinaemia and associated vitamin factors among the general population, and less still among children. Cardiovascular risk factors in the childhood population may be related to the appearance of cardiovascular disease at adult age. The aim of this study is to establish a definition of hyperhomocysteinaemia in adolescents and to analyze the influence of vitamin and metabolic factors in homocysteine levels in this population group. Methods Descriptive, cross-sectional epidemiological study to estimate serum homocysteine, vitamin B12 and folate levels, as well as plasma total, HDL- and LDL- cholesterol in a schoolgoing population aged 13 to 17 years in Madrid, Spain. Spearman correlation analysis was performed to ascertain quantitative comparison, Pearson's χ2 test (frequency < 5, Fisher) was used for comparison of prevalences, Mann-Whitney U and Kruskal-Wallis test were used for comparison of means and Bonferroni correction was used for post-hoc tests. A multivariate logistic regression model was performed in the multivariate analysis. Results Based on the classic values for definition of hyperhomocysteinaemia in adults, prevalence of hyperhomocysteinaemia in the study population was: 1.26% for 15 μmol/L; and 2.52% for 12 μmol/L. Deficits in HDL cholesterol and serum folate levels yielded adjusted Odds Ratios (OR) for hyperhomocysteinemia of 2.786, 95% CI (1.089-7.126), and 5.140, 95% CI (2.347-11.256) respectively. Mutation of the methylenetetrahydrofolate reductase (MTHFR) C677T genotype also raises the risk of hyperhomocysteinaemia (CC→CT: OR = 2.362; 95% CI (1.107-5.042) CC→TT: OR = 6.124, 95% CI (2.301-16.303)) Conclusion A good definition of hyperhomocysteinaemia in adolescents is the 90th percentile, equivalent to 8.23 μmol/L. Risk factors for hyperhomocysteinaemia are cHDL and folate deficiency, and

  14. Homocysteine in embryo culture media as a predictor of pregnancy outcome in assisted reproductive technology.

    PubMed

    Boyama, Burcu Aydin; Cepni, Ismail; Imamoglu, Metehan; Oncul, Mahmut; Tuten, Abdullah; Yuksel, Mehmet Aytac; Kervancioglu, Mehmet Ertan; Kaleli, Semih; Ocal, Pelin

    2016-01-01

    The aim of this study was to determine whether homocysteine (hcy) concentrations in embryo culture media correlate with pregnancy outcome in assisted reproductive technology (ART) cycles. Forty patients who underwent single embryo transfer at the infertility clinic of a tertiary care center were recruited for this case-control study. Spent embryo culture media from all patients were collected after single embryo transfer on day 3 (n = 40). Hcy concentrations in embryo culture media were analyzed by enzyme cycling method. Patients were grouped according to the diagnosis of a clinical pregnancy. Sixteen patients were pregnant while 24 patients failed to achieve conception. Mean Hcy levels in the culture media were significantly different between the groups (p < 0.003), as 4.58 ± 1.31 μmol/l in the non-pregnant group and 3.37 ± 0.92 μmol/l in the pregnant group. Receiver operator curve analysis for determining the diagnostic potential of Hcy for pregnancy revealed an area under the curve of 0.792 (confidence interval: 0.65-0.94; p < 0.05). A cut-off value of 3.53 μmol/l was determined with a sensitivity of 83.3%, and a specificity of 68.8%. Lower hcy levels were associated with a better chance of pregnancy and better embryo grades. Hcy may be introduced as an individual metabolomic profiling marker for embryos.

  15. Whey protein supplementation increases methionine intake but not homocysteine plasma concentration in rats.

    PubMed

    Deminice, Rafael; Comparotto, Hugo; Jordao, Alceu Afonso

    2015-01-01

    The purpose of this study was to examine the effects of whey protein supplementation on homocysteine (Hcy) metabolism and liver oxidative stress in rats. Twenty-four rats were divided into 3 groups (n = 8) to receive one of the following diets for 4 weeks: control diet (C), whey protein-composed diet (WP), and whey protein-supplemented diet (WPS). The C and WP diets consisted of AIN-93 with 20% casein and 20% whey protein as protein source, respectively. WPS was AIN-93 (20% casein) supplemented by the addition of 20% (w/w) whey protein. Four weeks of ingesting a WPS diet resulted in a significantly higher (P < 0.05) total protein and methionine intakes. Although a significant increase (P < 0.05) in the hepatic S-adenosylmethionine and S-adenosylhomocysteine levels occurred in WPS group compared with C and WP, no significant change was observed in plasma Hcy concentration between groups. Furthermore, the levels of lipid hydroperoxides and advanced oxidation protein products, known liver oxidative stress markers, were increased in the WPS group compared with the C group. In addition, no change in glutathione liver concentration was observed in any of the groups studied. In conclusion, whey protein supplementation increases methionine intake substantially; however, it does not change plasma Hcy concentrations. On the other hand, increased hepatic oxidative stress markers were observed in whey protein supplemented rats were probably due to high protein intake.

  16. Regulation of homocysteine homeostasis through the transcriptional coactivator PGC-1alpha.

    PubMed

    Li, Siming; Arning, Erland; Liu, Chang; Vitvitsky, Victor; Hernandez, Carlos; Banerjee, Ruma; Bottiglieri, Teodoro; Lin, Jiandie D

    2009-03-01

    Plasma homocysteine (Hcy) is an independent risk factor for cardiovascular disease. Hcy is a nonprotein amino acid derivative that is generated from the methionine cycle, which provides the methyl group for essentially all biological methylation reactions. Although plasma Hcy levels are elevated in patients with cardiovascular disease, the mechanisms that regulate Hcy homeostasis remain poorly defined. In this study, we found that the expression of key enzymes involved in Hcy metabolism is induced in the liver in response to fasting. This induction coincides with increased expression of peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1alpha, a transcriptional coactivator that regulates hepatic gluconeogenesis and mitochondrial function. PGC-1alpha stimulates the expression of genes involved in Hcy metabolism in cultured primary hepatocytes as well as in the liver. Adenoviral-mediated expression of PGC-1alpha in vivo leads to elevated plasma Hcy levels. In contrast, mice deficient in PGC-1alpha have lower plasma Hcy concentrations. These results define a novel role for the PGC-1alpha coactivator pathway in the regulation of Hcy homeostasis and suggest a potential pathogenic mechanism that contributes to hyperhomocysteinemia.

  17. Vitamin B(12) deficiency stimulates osteoclastogenesis via increased homocysteine and methylmalonic acid.

    PubMed

    Vaes, Bart L T; Lute, Carolien; Blom, Henk J; Bravenboer, Nathalie; de Vries, Teun J; Everts, Vincent; Dhonukshe-Rutten, Rosalie A; Müller, Michael; de Groot, Lisette C P G M; Steegenga, Wilma T

    2009-05-01

    The risk of nutrient deficiencies increases with age in our modern Western society, and vitamin B(12) deficiency is especially prevalent in the elderly and causes increased homocysteine (Hcy) and methylmalonic acid (MMA) levels. These three factors have been recognized as risk factors for reduced bone mineral density and increased fracture risk, though mechanistic evidence is still lacking. In the present study, we investigated the influence of B(12), Hcy, and MMA on differentiation and activity of bone cells. B(12) deficiency did not affect the onset of osteoblast differentiation, maturation, matrix mineralization, or adipocyte differentiation from human mesenchymal stem cells (hMSCs). B(12) deficiency caused an increase in the secretion of Hcy and MMA into the culture medium by osteoblasts, but Hcy and MMA appeared to have no effect on hMSC osteoblast differentiation. We further studied the effect of B(12), Hcy, and MMA on the formation of multinucleated tartrate-resistant acid phosphatase-positive osteoclasts from mouse bone marrow. We observed that B(12) did not show an effect on osteoclastogenesis. However, Hcy as well as MMA were found to induce osteoclastogenesis in a dose-dependent manner. On the basis of these results, we conclude that B(12) deficiency may lead to decreased bone mass by increased osteoclast formation due to increased MMA and Hcy levels.

  18. Histamine release and fibrinogen adsorption mediate acute inflammatory responses to biomaterial implants in humans

    PubMed Central

    Zdolsek, Johann; Eaton, John W; Tang, Liping

    2007-01-01

    Background Medical implants often fail as a result of so-called foreign body reactions during which inflammatory cells are recruited to implant surfaces. Despite the clinical importance of this phenomenon, the mechanisms involved in these reactions to biomedical implants in humans are not well understood. The results from animal studies suggest that both fibrinogen adsorption to the implant surface and histamine release by local mast cells are involved in biomaterial-mediated acute inflammatory responses. The purpose of this study was to test this hypothesis in humans. Methods Thirteen male medical student volunteers (Caucasian, 21–30 years of age) were employed for this study. To assess the importance of fibrinogen adsorption, six volunteers were implanted with polyethylene teraphthalate disks pre-coated with their own (fibrinogen-containing) plasma or (fibrinogen-free) serum. To evaluate the importance of histamine, seven volunteers were implanted with uncoated disks with or without prior oral administration of histamine receptor antagonists. The acute inflammatory response was estimated 24 hours later by measuring the activities of implant-associated phagocyte-specific enzymes. Results Plasma coated implants accumulated significantly more phagocytes than did serum coated implants and the recruited cells were predominantly macrophage/monocytes. Administration of both H1 and H2 histamine receptor antagonists greatly reduced the recruitment of macrophages/monocytes and neutrophils on implant surfaces. Conclusion In humans – as in rodents – biomaterial-mediated inflammatory responses involve at least two crucial events: histamine-mediated phagocyte recruitment and phagocyte accumulation on implant surfaces engendered by spontaneously adsorbed host fibrinogen. Based on these results, we conclude that reducing fibrinogen:surface interactions should enhance biocompatibility and that administration of histamine receptor antagonists prior to, and shortly after

  19. Gelation of fibrinogen in plasma. A kinetic study by turbidity measurement.

    PubMed

    Regañon, E; Vila, V; Aznar, J

    1984-01-01

    Studies of the turbidity profiles of diluted (1/55, v/v) normal plasma, thrombin activity free serum plus commercial fibrinogen, and 0.15 M NaCl, pH 7.4, plus commercial fibrinogen, activated by thrombin or reptilase and measured at 350 nm, have shown that the latency time (LT) hardly varies for the fibrinogen concentration within limits of 0.03-0.15 mg/ml; however, it does vary for the thrombin concentration. The rate of gelation (RG) varies linearly with the fibrinogen (FG) concentration, conforming to the equation RG = 0.027 (FG)1.8; it hardly varies for thrombin concentrations greater than 0.50 NIH U/ml. On the other hand, RG values obtained for 0.46 NIH U/ml of thrombin or 0.92 BU/ml of reptilase show no significant differences. The variation in LT for the thrombin or reptilase concentration allows the rate of activation to be estimated, giving values of 5.9 X 10(-12) and 3.2 X 10(-12) mol/U/s, respectively, for a fibrinogen concentration in plasma of 1.1 X 10(-10) mol/ml. The mean value estimated for the ratio LT/FG in normal plasma is 35.76 +/- 18.3 and 85.62 +/- 18.3 s mg-1 ml for activation by thrombin and reptilase, respectively. We have studied in normal plasma the parameters that define the gelation of fibrin as measured by turbidity curves and their variation according to the fibrinogen concentration. This permits us to establish the kinetics of fibrin gel formation and normal range values.

  20. Maternal homocysteine in pregnancy and offspring birthweight: epidemiological associations and Mendelian randomization analysis

    PubMed Central

    Yajnik, Chittaranjan S; Chandak, Giriraj R; Joglekar, Charudatta; Katre, Prachi; Bhat, Dattatray S; Singh, Suraj N; Janipalli, Charles S; Refsum, Helga; Krishnaveni, Ghattu; Veena, Sargoor; Osmond, Clive; Fall, Caroline HD

    2014-01-01

    Background: Disturbed one-carbon (1-C) metabolism in the mother is associated with poor fetal growth but causality of this relationship has not been established. Methods: We studied the association between maternal total homocysteine and offspring birthweight in the Pune Maternal Nutrition Study (PMNS, Pune, India) and Parthenon Cohort Study (Mysore, India). We tested for evidence of causality within a Mendelian randomization framework, using a methylenetetrahydrofolatereductase (MTHFR) gene variant rs1801133 (earlier known as 677C→T) by instrumental variable and triangulation analysis, separately and using meta-analysis. Results: Median (IQR) homocysteine concentration and mean (SD) birthweight were 8.6 µmol/l (6.7,10.8) and 2642 g (379) in the PMNS and 6.0 µmol/l (5.1,7.1) and 2871 g (443) in the Parthenon study. Offspring birthweight was inversely related to maternal