Search results for "folate"

Heavy enzymes and the rational redesign of protein catalysts

2019

Abstract An unsolved mystery in biology concerns the link between enzyme catalysis and protein motions. Comparison between isotopically labelled “heavy” dihydrofolate reductases and their natural‐abundance counterparts has suggested that the coupling of protein motions to the chemistry of the catalysed reaction is minimised in the case of hydride transfer. In alcohol dehydrogenases, unnatural, bulky substrates that induce additional electrostatic rearrangements of the active site enhance coupled motions. This finding could provide a new route to engineering enzymes with altered substrate specificity, because amino acid residues responsible for dynamic coupling with a given substrate present…

A Hazelnut-Enriched Diet Modulates Oxidative Stress and Inflammation Gene Expression without Weight Gain

2019

Introduction. Inflammation is associated with obesity condition and plays a pivotal role in the onset and progression of many chronic diseases. Among several nutraceutical foods, hazelnuts (Corylus avellana L.) are considered an excellent anti-inflammatory and hypolipidemic food being the second richest source of monounsaturated fatty acids among nuts and because they are rich in vitamins, minerals, and phenolic compounds. Materials and Methods. A prospective pilot clinical trial on 24 healthy volunteers who consumed daily, as a snack, 40 g of hazelnuts (261.99 kcal/1096.17 kJ) for six weeks was conducted. Anthropometric measurements, body composition analysis, and nutrigenomic analysis on …

Albumin-Folate Conjugates for Drug-targeting in Photodynamic Therapy.

2016

Photodynamic therapy (PDT) is based on the cytotoxicity of photosensitizers in the presence of light. Increased selectivity and effectivity of the treatment is expected if a specific uptake of the photosensitizers into the target cells, often tumor cells, can be achieved. An attractive transporter for that purpose is the folic acid receptor α (FRα), which is overexpressed on the surface of many tumor cells and mediates an endocytotic uptake. Here, we describe the synthesis and photobiological characterization of polar β-carboline derivatives as photosensitizers covalently linked to folate-tagged albumin as the carrier system. The particles were taken up by KB (human carcinoma) cells within …

Homocysteine concentration in coronary artery disease: Influence of three common single nucleotide polymorphisms.

2017

Whether single nucleotide polymorphisms (SNPs) of homocysteine metabolism enzymes influence the rate of cardiovascular (CV) events in coronary artery disease (CAD) patients remains controversial.In this analysis, 1126 subjects from the AtheroGene study with CAD and 332 control subjects without known CAD were included. The following SNPs were investigated: methylentetrahydrofolate reductase (MTHFR-C667T), methionin synthetase (MS-D919G), and cystathionin beta synthetase (CBS-I278T). The endpoint was the combination of cardiovascular death, stroke, and non-fatal myocardial infarction (N = 286). The median follow-up time was 6.4 years. Kaplan-Meier curve analysis showed an increasing event rat…

Proton-coupled folate transporter as a biomarker of outcome to treatment for pleural mesothelioma.

2018

Comparison Study of Two Differently Clicked 18F-Folates—Lipophilicity Plays a Key Role

2018

Within the last decade, several folate-based radiopharmaceuticals for Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) have been evaluated; however, there is still a lack of suitable 18F-folates for clinical PET imaging. Herein, we report the synthesis and evaluation of two novel 18F-folates employing strain-promoted and copper-catalyzed click chemistry. Furthermore, the influence of both click-methods on lipophilicity and pharmacokinetics of the 18F-folates was investigated. 18F-Ala-folate and 18F-DBCO-folate were both stable in human serum albumin. In vitro studies proved their high affinity to the folate receptor (FR). The lipophilic character of …

Minimization of dynamic effects in the evolution of dihydrofolate reductase

2015

Protein isotope labeling is a powerful technique to probe functionally important motions in enzyme catalysis and can be applied to investigate the conformational dynamics of proteins.

PAI-1 4G-4G, MTHFR 677TT, V Leiden 506Q, and Prothrombin 20210A in Splanchnic Vein Thrombosis: Analysis of Individual Patient Data From Three Prospec…

2015

There are no univocal opinions on the role of genetic thrombophilia on splanchnic vein thrombosis (SVT). We defined genetic thrombophilia the presence of one of these thrombophilic genetic factors (THRGFs): PAI-1 4G-4G, MTHFR 677TT, V Leiden 506Q, and prothrombin 20210A.To evaluate the frequencies of these THRGFs in SVT patients, we analyzed individual data of 482 Caucasian patients, recruited from 2000 to 2014 in three prospective studies. SVT was defined as the presence of thrombosis of portal (PVT), mesenteric (MVT), splenic (SPVT), cava (CT), and hepatic vein (Budd Chiari syndrome, BCS). Pre-hepatic SVT (pre-HSVT) was defined as PVT with or without MVT/SPVT, without BCS. Post-hepatic SV…

Exposure to Toxic Heavy Metals Can Influence Homocysteine Metabolism?

2019

Background: Homocysteine is a sulfur amino acid whose metabolism is activated in two pathways: remethylation to methionine, which requires folate and vitamin B12, and transsulfuration to cystathionine, which needs pyridoxal-5’-phosphate. High homocysteine level increases the risk of developing heart disease, stroke, peripheral vascular diseases, and cognitive impairment. Some evidence showed that exposure to these metals increased plasma homocysteine levels. Methods: A systematic review was carried out to clarify the relationship between homocysteine blood levels and exposure to toxic heavy metals (Lead, Cadmium, Mercury, and Chromium). Results: The results of this systematic review i…

Effects of marathon running on plasma total homocysteine concentrations.

2003

Summary Aims There is evidence of an excess of acute cardiovascular (CV) events in marathon runners. High plasma total homocysteine (tHcy) concentrations are a recognised risk factor for CV events. Therefore, we investigated the changes in plasma tHcy concentrations 24 h before and after a marathon race. Methods and results Twenty-two non-professional male athletes, mean age 35.6 (6.6), range 23–49 years, were studied the day before and 24 h after finishing a marathon race. None of the athletes was a carrier of the MTHFR 677TT genotype and no ingestion of supplements of vitamins (B12, B6, folic acid) was allowed. Results Changes in plasma folate and plasma vitamin B12 concentrations were no…