Read by QxMD icon Read


Seu Ping Guiraud, Ivan Montoliu, Laeticia Da Silva, Loïc Dayon, Antonio Núñez Galindo, John Corthésy, Martin Kussmann, Francois-Pierre Martin
The methionine cycle is a key pathway contributing to the regulation of human health, with well-established involvement in cardiovascular diseases and cognitive function. Changes in one-carbon cycle metabolites have also been associated with mild cognitive decline, vascular dementia, and Alzheimer's disease. Today, there is no single analytical method to monitor both metabolites and co-factors of the methionine cycle. To address this limitation, we here report for the first time a new method for the simultaneous quantitation of 17 metabolites in the methionine cycle, which are homocysteic acid, taurine, serine, cysteine, glycine, homocysteine, riboflavin, methionine, pyridoxine, cystathionine, pyridoxamine, S-adenosylhomocysteine, S-adenosylmethionine, betaine, choline, dimethylglycine, and 5-methyltetrahydrofolic acid...
October 18, 2016: Analytical and Bioanalytical Chemistry
Yu Kobayashi, Jun Tohyama, Tomoyuki Akiyama, Shinichi Magara, Hideshi Kawashima, Noriyuki Akasaka, Mitsuko Nakashima, Hirotomo Saitsu, Naomichi Matsumoto
Cerebral folate deficiency due to folate receptor 1 gene (FOLR1) mutations is an autosomal recessive disorder resulting from a brain-specific folate transport defect. It is characterized by late infantile onset, severe psychomotor regression, epilepsy, and leukodystrophy. We describe a consanguineous girl exhibiting severe developmental regression, intractable epilepsy, polyneuropathy, and profound hypomyelination with cortical involvement. Magnetic resonance imaging showed cortical disturbances in addition to profound hypomyelination and cerebellar atrophy...
October 12, 2016: Brain & Development
Patricie Burda, Terttu Suormala, Dorothea Heuberger, Alexandra Schäfer, Brian Fowler, D Sean Froese, Matthias R Baumgartner
5,10-Methylenetetrahydrofolate reductase (MTHFR) catalyzes the NADPH-dependent reduction of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate using FAD as the cofactor. Severe MTHFR deficiency is the most common inborn error of folate metabolism, resulting in hyperhomocysteinemia and homocystinuria. Approximately 70 missense mutations have been described that cause severe MTHFR deficiency, however, in most cases their mechanism of dysfunction remains unclear. Few studies have investigated mutational specific defects; most of these assessing only activity levels from a handful of mutations using heterologous expression...
October 14, 2016: Journal of Inherited Metabolic Disease
Karen E Christensen, Wenyang Hou, Renata H Bahous, Liyuan Deng, Olga V Malysheva, Erland Arning, Teodoro Bottiglieri, Marie A Caudill, Loydie A Jerome-Majewska, Rima Rozen
BACKGROUND: Moderately high folic acid intake in pregnant women has led to concerns about deleterious effects on the mother and fetus. Common polymorphisms in folate genes, such as methylenetetrahydrofolate dehydrogenase-methenyltetrahydrofolate cyclohydrolase-formyltetrahydrofolate synthetase (MTHFD1) R653Q, may modulate the effects of elevated folic acid intake. OBJECTIVES: We investigated the effects of moderate folic acid supplementation on reproductive outcomes and assessed the potential interaction of the supplemented diet with MTHFD1-synthetase (Mthfd1S) deficiency in mice, which is a model for the R653Q variant...
October 5, 2016: American Journal of Clinical Nutrition
Markus Kopp, Kerstin Dürr, Matthias Steigleder, Thomas Clavel, Michael Rychlik
Folate-producing bifidobacteria have been studied extensively but appropriate methods for detailed quantitation of intra- and extracellular pteroylmono- and pteroylpolyglutamate patterns are lacking. Therefore, B. adolescentis DSM 20083(T) was cultivated in folate-free medium (FFM) for 24h to develop and validate stable isotope dilution assays (SIDAs) coupled with LC-MS/MS for the determination of 5-formyltetrahydrofolic acid (5-HCO-H4folate), 10-formylfolic acid (10-HCO-PteGlu), tetrahydrofolic acid (H4folate), folic acid (PteGlu) and 5-methyltetrahydrofolic acid (5-CH3-H4folate) including its di-, tri-, and tetraglutamic vitamers (5-CH3-H4PteGlu2-4)...
October 21, 2016: Journal of Chromatography. A
A Mazza, A F Cicero, E Ramazzina, S Lenti, L Schiavon, E Casiglia, G Gussoni
Although the role of homocysteine (HCys) in secondary cardiovascular prevention has been scaled down, hyper-homocysteinemia remains a risk factor for cerebrovascular events. The aim of this study was to investigate the efficacy of nutraceuticals in lowering HCys serum levels versus a conventional vitamin supplementation in hypertensive subjects at low cardiovascular risk. One-hundred and four patients (mean age 62.8±14.5 years, 63.5% males), 52 for each treatment group, were enrolled. The study recruited patients with stage 1 essential hypertension and hyper-homocysteinemia (HCys ≥15 μmol/L), without a history of cardiovascular and cerebrovascular disease...
July 2016: Journal of Biological Regulators and Homeostatic Agents
Aikaterini Oikonomidi, Piotr Lewczuk, Johannes Kornhuber, Yvo Smulders, Michael Linnebank, Alexander Semmler, Julius Popp
Disturbed homocysteine metabolism may contribute to amyloidogenesis by modulating the amyloid precursor protein (APP) production and processing. The objective of this study was to investigate the relationships between cerebral amyloid production and both blood and cerebrospinal fluid (CSF) markers of the homocysteine metabolism. We assessed CSF concentrations of soluble APPα, soluble APPβ, and amyloid β1-42 (Aβ1-42), as well as plasma levels of homocysteine (Hcys), total vitamin B12, and folate, and CSF concentrations of homocysteine (Hcys-CSF), 5-methyltetrahydrofolate (5-MTHF), S-adenosylmethionine (SAM), and S-adenosylhomocysteine (SAH) in 59 subjects with normal cognition...
October 2016: Journal of Neurochemistry
Qian Zhang, Sandra J Bertics, N Daniel Luchini, Heather M White
Metabolizable methionine (Met) concentrations can be increased by feeding rumen-protected dl-Met or the isopropyl ester of 2-hydroxy-4-(methylthio) butanoic acid (HMBi). Hepatic responses to increasing concentrations of metabolizable Met as a result of supplementation of different Met sources have not been comparatively examined. The objective of this experiment was to examine the regulation of key genes for Met metabolism, gluconeogenesis, and fatty acid oxidation in response to increasing concentrations of dl-Met or 2-hydroxy-4-(methylthio) butanoic acid (HMB) in bovine primary hepatocytes...
October 2016: Journal of Dairy Science
Haruhisa Nakao, Kenji Wakai, Norimitsu Ishii, Yuji Kobayashi, Kiyoaki Ito, Masashi Yoneda, Mitsuru Mori, Masanori Nojima, Yasutoshi Kimura, Takao Endo, Masato Matsuyama, Hiroshi Ishii, Makoto Ueno, Sawako Kuruma, Naoto Egawa, Keitaro Matsuo, Satoyo Hosono, Shinichi Ohkawa, Kozue Nakamura, Akiko Tamakoshi, Mami Takahashi, Kazuaki Shimada, Takeshi Nishiyama, Shogo Kikuchi, Yingsong Lin
BACKGROUND: Evidence supporting the associations between folate metabolizing gene polymorphisms and pancreatic cancer has been inconclusive. We examined their associations in a case-control study of Japanese subjects. METHODS: Our case-control study involved 360 newly diagnosed pancreatic cancer cases and 400 frequency-matched, non-cancer control subjects. We genotyped four folate metabolizing gene polymorphisms, including two polymorphisms (rs1801133 and rs1801131) in the methylenetetrahydrofolate (MTHFR) gene, one polymorphism (rs1801394) in the 5-methyltetrahydrofolate-homocysteine methyltransferase reductase (MTRR) gene and one polymorphism (rs1805087) in the 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR) gene...
2016: BMC Gastroenterology
A Sobczyńska-Malefora, J Cutler, Y Rahman
A 21 year old male presented with a history of intermittent, transient neurological events. A brain MRI showed an area of restricted diffusion in keeping with an infarct, and an angiogram demonstrated an intracranial stenosis in the internal carotid artery, consistent with atherosclerosis. Laboratory investigations revealed a highly elevated plasma homocysteine, with low plasma folate and 5-methyltetrahydrofolate and methionine at the lower end of the normal ranges. The homocysteine normalized following treatment with folic acid...
October 2016: Metabolic Brain Disease
Mari Akiyama, Tomoyuki Akiyama, Kaoruko Kanamaru, Mutsuko Kuribayashi, Hiroko Tada, Tsugumi Shiokawa, Soichiro Toda, Katsumi Imai, Yu Kobayashi, Jun Tohyama, Takafumi Sakakibara, Harumi Yoshinaga, Katsuhiro Kobayashi
OBJECTIVE: To describe an assay of 5-methyltetrahydrofolate (5MTHF) in the cerebrospinal fluid (CSF) of children, to determine reference values, and to report the clinical significance of this assay in metabolic disorders affecting folate transport and metabolism. METHODS: CSF 5MTHF was determined by high-performance liquid chromatography with fluorescent detection in pediatric patients including one with FOLR1 gene mutation and one with methylenetetrahydrofolate reductase (MTHFR) deficiency...
September 1, 2016: Clinica Chimica Acta; International Journal of Clinical Chemistry
Françoise Delmelle, Beat Thöny, Philippe Clapuyt, Nenad Blau, Marie-Cécile Nassogne
BACKGROUND: Cerebral folate transporter deficiency caused by FOLR-1 mutations has been described in 2009. This condition is characterized by a 5MTHF level <5 nmol/l in the CSF, along with regression of acquisition in the second year of life, ataxia, and refractory myoclonic epilepsy. Oral or intravenous folinic acid (5-formyltetrahydrofolate) treatment has been shown to improve clinical status. CASE PRESENTATION: We present the cases of two sisters with cerebral folate transport deficiency caused by mutation in the folate receptor 1 (FOLR1) gene (MIM *136430)...
September 2016: European Journal of Paediatric Neurology: EJPN
Markus Kopp, Rosalie Morisset, Peter Koehler, Michael Rychlik
Folate deficiency is generally accepted as a potential direct or indirect risk factor for diseases including spina bifida, coronary heart diseases, malfunctions of the central nervous system, and cancer. The direct inclusion of folates in the methylation cycle, including the remethylation of homocysteine and regeneration of S-adenosylmethionine, underlines the importance of these vitamins and other components of one-carbon metabolism. Therefore, the aim of the present study was to develop a multiple stable isotope dilution assay (SIDA) for the respective analytes in plasma and tissue samples to allow for a closer look at the interaction between a severe folate deficiency and local folate status, as well as further interactions with circulating S-adenosylmethionine, S-adenosylhomocysteine, and homocysteine...
2016: PloS One
John Shoffner, Barbara Trommer, Audrey Thurm, Cristan Farmer, William A Langley, Laura Soskey, Aldeboran N Rodriguez, Precilla D'Souza, Sarah J Spence, Keith Hyland, Susan E Swedo
OBJECTIVE: To examine the association between cerebral folate deficiency and autism, this study examined CSF 5-methyltetrahydrofolate (5-MTHF) concentrations in a group of young children with autism, investigated the natural variation in CSF 5-MTHF over time, and assessed the relationship between CSF 5-MTHF and symptoms. METHODS: CSF was collected from 67 children with a diagnosis of DSM-IV-TR autistic disorder (age, mean ± SD 43 ± 11 months), with a second CSF sample obtained 1-3 years later on 31 of these subjects (time to follow-up, 30 ± 8 months)...
June 14, 2016: Neurology
Małgorzata Bednarska-Makaruk, Ałła Graban, Agata Sobczyńska-Malefora, Dominic J Harrington, Michael Mitchell, Kieran Voong, Letian Dai, Wanda Łojkowska, Anna Bochyńska, Danuta Ryglewicz, Anna Wiśniewska, Hanna Wehr
Epigenetics (particularly DNA methylation) together with environmental and genetic factors, are key to understanding the pathogenesis of many diseases including dementia. Disturbances in DNA methylation have already been implicated in dementia. Homocysteine metabolism, with folate and vitamin B12 as essential cofactors, is integral to methylation processes. We evaluated in a case-control study the association of global DNA methylation, homocysteine, folate and vitamin B12 status with dementia. Selected polymorphisms of genes previously associated with dementia development and the influence of various factors on DNA methylation were also investigated...
August 2016: Experimental Gerontology
Zhewei Fei, Yong Gao, Mingke Qiu, Xianqin Qi, Yuxin Dai, Shuqing Wang, Zhiwei Quan, Yingbin Liu, Jingmin Ou
Folic acid supplementation may meliorate cardiovascular disease risk by improving vascular endothelial structure and function. However, the underlying mechanisms are still lack of a global understanding. To be used, folic acid must be converted to 7,8-dihydrofolate by dihydrofolate reductase to generate one-carbon derivatives serving as important cellular cofactors in the synthesis of nucleotides and amino acids required for cell growth. Therefore, this study explored the effect of dihydrofolate reductase knockdown on endothelial EA...
March 2016: Journal of Clinical Biochemistry and Nutrition
L Knowles, A A M Morris, J H Walter
S-adenosyl methionine, which is formed from methionine, is an essential methyl donor within the central nervous system. Methionine is formed by the enzyme methionine synthase for which 5-methyltetrahydrofolate (5-MTHF) and homocysteine are substrates. Patients with severe methylenetetrahydrofolate reductase (MTHFR) deficiency cannot make 5-MTHF and have extremely low levels in the CSF. As a consequence, methylation reactions in the CNS are compromised, and this is likely to play an important role in the neurological abnormalities that occur in MTHFR deficiency...
February 23, 2016: JIMD Reports
Clemens C Stoffregen, Elisabeth A Odin, Göran U Carlsson, Göran K Kurlberg, Hillevi G Björkqvist, Maria T Tångefjord, Bengt G Gustavsson
The objectives of this single-center, open-label, phase II study were to evaluate (a) the feasibility and safety of neoadjuvant administration of pemetrexed with oral folic acid and vitamin B12 (FA/B12) in newly diagnosed patients with resectable rectal cancer and (b) intracellular and systemic vitamin metabolism. Patients were treated with three cycles of pemetrexed (500 mg/m, every 3 weeks) and FA/B12 before surgery. The reduced folates tetrahydrofolate, 5-methyltetrahydrofolate, and 5,10-methylenetetrahydrofolate were evaluated from biopsies in tumor tissue and in adjacent mucosa...
June 2016: Anti-cancer Drugs
Wolfgang Stuetz, Verena I Carrara, Rose Mc Gready, Sue J Lee, Kanlaya Sriprawat, Basi Po, Borimas Hanboonkunupakarn, Tilman Grune, Hans K Biesalski, François H Nosten
Micronutrient fortified flour (MFF), supplementary food rations and micronutrient (MN) supplements may prevent deficiencies among pregnant women. Objectives of cross-sectional surveys in 2004 (n = 533) and 2006 (n = 515) were to assess the impact of new food rations (flour, oil) and supplements on MN status by trimester of pregnancy in the Maela refugee camp. Hemoglobin, iron status, zinc, retinol, β-carotene and tryptophan decreased, while α-/γ-tocopherol and 5-methyltetrahydrofolate (5-MTHF) increased from first to third trimester...
February 2016: Nutrients
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"