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Methylenetetrahydrofolate Reductase (MTHFR) deficiency, is avery rare congenital defect of folate metabolism, inherited in an autosomal recessive pattern included in newbornscreening (NBS) programs in Italy. It is caused by mutations in the MTHFRgene and is characterized by elevatedplasma homocysteine and borderline-low or normal methionine levels, causing severe neurological signs, recurrentapnoea, microcephaly and convulsions, generally during the neonatal period. An early treatment may prevent theclinical manifestations with a positive impact on patient’s health. We report a new case of MTHFRdeficiency, identified during NBS that showed hypomethioninemia 4.6 μmol/L (r.i.6-20). The second level-test revealed hyperhomocysteinemia (106.7 μM, r.i. 5-15). The whole sequencing of theMTHFRgene showed two missense mutation: c.176G>C (p.Trp59Ser), reported as disease causing and the novelc.1769T>G (p.Leu590Arg), classified as likely pathogenetic. The baby was immediately treated with vitamin B12,folate and betaine; after 12 months of follow-up he has no signs or symptoms of the disease. In conclusion, this case report highlights the importance of NBS for inborn errors of metabolism and genetic analysis,that can prevent the establishment of a serious disorder of folate metabolism.

Background The effects of sex and oral contraceptives (OCs) on blood metabolites have been scarcely studied. Considering the widespread use of OCs and the fact that protocol designs for clinical trials emphasise the use of contraception for women of childbearing potential, we examined if OCs and sex affect the serum levels of the physiologically relevant amino acids, carnitine and acylcarnitines, using metabolomics approaches. Methods Thirty-five healthy adult men and 67 women aged between 20 and 47 years were enrolled. They were drug free with the exception of women taking cyclic format OCs that contained ethinylestradiol and different progestins. OC-free women were analysed during the first ten days of their menstrual cycles, and amino acids, free carnitine and acylcarnitines were measured using HPLC or LC/MS/MS. Results The serum levels of alanine, serine, aspartic acid, arginine and taurine were not significantly different among the analysed groups. Men had significantly higher leucine, isoleucine, methionine, phenylalanine, asparagine, glutamine + glutamate, and histidine than women who did not use OCs, while tryptophan was significantly lower in men. OC use significantly decreased the levels of glycine, proline, glutamine + glutamate, lysine, hydroxyproline and ornitine when compared with non-user women. The level of free carnitine was higher in men than in women; in addition, OC use further reduced the levels of carnitine in women although the reduction is not significant. Total esterified carnitines were higher in untreated women when compared with that of men and OC users. Globally, the effect of OCs and sex was specific for the individual esterified carnitine. The observed metabolic changes were not attributable to renal or hepatic functions or to differences in body weight. Conclusion The assessed parameters were specifically influenced by sex, highlighting the need to have reference values for women and men. The major novelty of this study is the demonstration that OCs specifically change the profiles of serum amino acids and carnitine, which suggests that OC users and non-users should be represented in clinical trials.

Background and aims Metformin is the first-line therapy in type 2 diabetes. In patients inadequately controlled with metformin, the addition of a sulfonylurea or pioglitazone are equally plausible options to improve glycemic control. However, these drugs have profound differences in their mechanism of action, side effects, and impact on cardiovascular risk factors. A formal comparison of these two therapies in terms of cardiovascular morbidity and mortality is lacking. The TOSCA.IT study was designed to explore the effects of adding pioglitazone or a sulfonylurea on cardiovascular events in type 2 diabetic patients inadequately controlled with metformin. Methods Multicentre, randomized, open label, parallel group trial of 48 month duration. Type 2 diabetic subjects, 50–75 years, BMI 20–45 Kg/m 2 , on secondary failure to metformin monotherapy will be randomized to add-on a sulfonylurea or pioglitazone. The primary efficacy outcome is a composite endpoint of all-cause mortality, nonfatal myocardial infarction, nonfatal stroke, and unplanned coronary revascularization. Principal secondary outcome is a composite ischemic endpoint of sudden death, fatal and non-fatal myocardial infarction and stroke, endovascular or surgical intervention on the coronary, leg or carotid arteries, major amputations. Side effects, quality of life and economic costs will also be evaluated. Efficacy, safety, tolerability, and study conduct will be monitored by an independent Data Safety Monitoring Board. End points will be adjudicated by an independent external committee. Conclusions TOSCA.IT is the first on-going study investigating the head-to-head comparison of adding a sulfonylurea or pioglitazone to existing metformin treatment in terms of hard cardiovascular outcomes. Registration: Clinicaltrials.gov ID NCT00700856.

Nitroarenes are environmental contaminants produced during incomplete combustion processes. It has been reported that nitroreduction, the most important pathway of nitroarene toxification, occurs mainly in the liver and intestine. In the present study we have shown that red cells also possess the metabolic competence to reduce nitroarenes. In particular, 1,8-dinitropyrene, the nitroarene chosen as model compound, was reduced to the corresponding mono- and diamino-derivatives, 1-amino-8-nitropyrene and 1,8-diaminopyrene, by human lysate supplemented with cofactors.

1-Amino-8-nitropyrene (1,8-ANP), a product of 1,8-dinitropyrene metabolism by either bacterial or mammalian enzymes, is weakly mutagenic to the 'classical nitroreductase'-deficient Salmonella tester strain TA98NR. The addition to the test system of rat liver cytosol without cofactors did not produce any effect on the 1,8-ANP mutagenic response toward TA98NR strain. Conversely, when both rat hepatic cytosol and NADPH (1 mM) were added to the mutagenicity assay, a 10-fold increase in 1,8-ANP mutagenic activity was observed. This suggests the involvement of rat hepatic cytosolic NADPH-dependent nitroreductase(s) in 1,8-ANP mutagenic activation. The addition to the mutagenesis assay of pentachlorophenol, an inhibitor of O-acetyltransferase and sulfotransferase, produced a dose-dependent decrease of 1,8-ANP mutagenic activation, whereas 2,6-dichloro-4-nitrophenol, a more specific inhibitor of sulfotransferase than O-acetyltransferase, did not affect the activation of 1,8-ANP to a mutagen at concentrations that selectively inhibit only bacterial sulfotransferase. This indicates that bacterial O-acetyltransferase but not sulfotransferase plays a role in the mutagenic activation of 1,8-ANP. Addition of acetyl co-enzyme A (AcCoA) and adenosine 3'-phosphate 5'-phosphosulfate (PAPS), cofactors for O-acetyl-transferase and sulfotransferase respectively, to the test system caused a dose-dependent inhibition of 1,8-ANP mutagenic activation by rat liver cytosol and NADPH, probably due to the formation of highly reactive O-acetoxy and N-sulfate ester derivatives of 1,8-ANP, which react with nucleophilic sites before reaching bacterial DNA. This hypothesis was confirmed by DNA covalent binding in in vitro experiments showing that both the cofactors AcCoA and PAPS enhanced the NADPH/rat liver cytosol-mediated covalent binding of 1,8-ANP to DNA from calf thymus 10- and 3-fold respectively. It seems likely that rat hepatic cytosolic nitroreductases activate 1,8-ANP to an N-hydroxyarylamine derivative which can be further metabolized to mutagenic species by either bacterial or mammalian O-acetyltransferase.

Quantitation of paint powders of ancient wall paintings is often hindered by the calcite contamination during samples withdrawal. To overcome this problem, a new approach was explored based on the mechanical pulverization of the paint powder followed by the evaluation of its true concentration, namely binders, pigments, and decaying compounds, from the comparison of the calcite FT-IR peak area at 2510 cm−1 with that of the corresponding underlying calcite used as calibrator. After extraction of the pulverized paint powder with polar and nonpolar solvents, liquid chromatography, gas chromatography with flame ionization detection, and gas chromatography–mass spectrometry were used to estimate the free amino acids, and fatty acids profiles. Compared to our previous investigation, the results obtained showed a better yield of the extracted organic materials as mg/kg of powder and also a qualitative improvement of the lipids profile.

Sex differences affect several diseases and are organ-and parameter-specific. In humans and animals, sex differences also influence the metabolism and homeostasis of amino acids and fatty acids, which are linked to the onset of diseases. Thus, the use of targeted metabolite profiles in tissues represents a powerful approach to examine the intermediary metabolism and evidence for any sex differences. To clarify the sex-specific activities of liver, heart and kidney tissues, we used targeted metabolomics, linear discriminant analysis (LDA), principal component analysis (PCA), cluster analysis and linear correlation models to evaluate sex and organ-specific differences in amino acids, free carnitine and acylcarnitine levels in male and female Sprague-Dawley rats. Several intra-sex differences affect tissues, indicating that metabolite profiles in rat hearts, livers and kidneys are organ-dependent. Amino acids and carnitine levels in rat hearts, livers and kidneys are affected by sex: male and female hearts show the greatest sexual dimorphism, both qualitatively and quantitatively. Finally, multivariate analysis confirmed the influence of sex on the metabolomics profiling. Our data demonstrate that the metabolomics approach together with a multivariate approach can capture the dynamics of physiological and pathological states, which are essential for explaining the basis of the sex differences observed in physiological and pathological conditions.

In the last years tandem mass spectrometry (MS/MS) has become a leading technology used for neonatal screening purposes. Newborn screening by MS/MS on dried blood spot samples (DBS) has one of its items in methionine levels: the knowledge of this parameter allows the identification of infant affected by homocystinuria (cystathionine β-synthase, CBS, deficiency) but can also lead, as side effect, to identify cases of methionine adenosyltransferase (MAT) type I/III deficiency.We started an expanded newborn screening for inborn errors of metabolism in Campania region in 2007. Here we report our ten years experience on expanded newborn screening in identifying patients affected by hypermethioninemia. During this period we screened approximately 77,000 infants and identified two cases: one case of classical homocystinuria and one patient affected by defect of MAT I/III. In this paper we describe these patients and their biochemical follow-up and review the literature concerning worldwide newborn screening reports on incidence of CBS and MAT deficiency. Keywords: Newborn screening, Hypermethioninemia, MAT I/III deficiency, CBS deficiency

Inborn errors of metabolism are genetic disorders due to impaired activity of enzymes, transporters, or cofactors resulting in accumulation of abnormal metabolites proximal to the metabolic block, lack of essential products or accumulation of by-products. Many of these disorders have serious clinical consequences for affected neonates, and an early diagnosis allows presymptomatic treatment which can prevent severe permanent sequelae and in some cases death. Expanded newborn screening for these diseases is a promising field of targeted metabolomics. Here we report the application, between 2007 and 2014, of this approach to the identification of newborns in southern Italy at risk of developing a potentially fatal disease. The analysis of amino acids and acylcarnitines in dried blood spots by tandem mass spectrometry revealed 24 affected newborns among 45,466 infants evaluated between 48 and 72 hours of life (overall incidence: 1 : 1894). Diagnoses of newborns with elevated metabolites were confirmed by gas chromatography-mass spectrometry, biochemical studies, and genetic analysis. Five infants were diagnosed with medium-chain acyl CoA dehydrogenase deficiency, 1 with methylmalonic acidemia with homocystinuria type CblC, 2 with isolated methylmalonic acidemia, 1 with propionic acidemia, 1 with isovaleric academia, 1 with isobutyryl-CoA dehydrogenase deficiency, 1 with beta ketothiolase deficiency, 1 with short branched chain amino acid deficiency, 1 with 3-methlycrotonyl-CoA carboxylase deficiency, 1 with formimino-transferase cyclodeaminase deficiency, and 1 with cystathionine-beta-synthase deficiency. Seven cases of maternal vitamin B12 deficiency and 1 case of maternal carnitine uptake deficiency were detected. This study supports the widespread application of metabolomic-based newborn screening for these genetic diseases.

Objectives Patients affected by Phenylketonuria (PKU) require lifelong management based on phenylalanine (Phe) and tyrosine (Tyr) restricted intake or tetrahydrobiopterin (BH4) administration. Frequent monitoring of blood concentration of both amino acids during treatment is the key point for clinicians to achieve the best long-term neuropsychological outcome. Results The present study develops and validates a rapid and simple method for Phe and Tyr quantization in dried blood spot (DBS) since this specimen has the advantage of being low invasive, easily withdrawn even at home and stable if mail-delivered. The validation studies showed the robustness of the method. Conclusions Serum and DBS samples from PKU patients were analyzed and compared, finding a good correlation of Phe and Tyr concentrations between the two different matrixes.

Plasma citrulline is known to be a marker of absorptive enterocyte mass in humans. We evaluated whether citrulline and other blood amino acids are indicators of residual small intestinal length and therefore potential predictors of dependence on parenteral nutrition in the long term. We studied 25 patients with short bowel syndrome (SBS) after at least 18 months since last digestive circuit modification; 24 of them were again evaluated 1 year later. Ten patients were weaned off parenteral nutrition and 15 were dependent on parenteral nutrition. Fifty-four healthy volunteers (28 women and 26 men) served as controls. Amino acid levels were determined on serum with high-performance liquid chromatography (HPLC) as well as on blood and serum with tandem mass spectrometry analysis. Five amino acids (citrulline, leucine, isoleucine, valine and tyrosine) were significantly lower in all SBS patients than in controls, whereas glutamine, measured only by HPLC, was significantly higher. Nevertheless, only serum citrulline measured with HPLC was significantly related to small bowel length. We conclude that HPLC remains the reference methodology to evaluate blood or serum amino acid levels in adult population with SBS.

Nitroarenes are environmental contaminants produced during incomplete combustion processes. Nitroreduction, the most important pathway of nitroarene toxification, occurs mainly in the liver and intestine. In the present study, we show that human red cells may also possess the metabolic competence to reduce 1-nitropyrene (NP) and 3-nitrofluoranthene (NF), the nitroarenes chosen as model compounds, to their corresponding amino derivatives, 1-aminopyrene (AP) and 3-aminofluoranthene (AF). The requirement of the cofactor couple NADH/FMN suggests that erythrocyte nitroreductase activity occurs via one electron transfer. The presence of oxygen strongly inhibited the haemolysate-catalyzed nitroarene reduction, whether measured as amine formation or nitroarene disappearance. Intermediate reactive species, that bind covalently to haemoglobin and/or other erythrocyte proteins, are formed during nitroreduction catalyzed by human haemolysate. In fact, the reduced metabolites AP and AF were released after mild acid hydrolysis of red cell proteins exposed to NP and NF, thus suggesting that sulphinamide adducts have been formed.

Lipid peroxidation was employed as an experimental model to study the antioxidant properties of avarol, a sesquiterpenoid hydroquinone and of its quinone, avarone. In the NADPH- or ascorbate-linked lipid peroxidation, avarol and avarone were shown to be more effective as inhibitors than in the t-BuOOH-dependent peroxidative process. However, in all three systems employed avarol was a more powerful inhibitor than avarone. The chemical structure of avarol, having an easily donatable hydrogen atom and its kinetics of inhibition suggested that the hydroquinone acted mainly as a radical scavenger. Conversely avarone appeared to interfere mainly with the initiation phase of lipid peroxidation. However, avarol and the semiquinone intermediate may contribute to the inhibitory action of the quinone. In fact avarone reduction to avarol has been shown to occur in the presence of reducing agents such as ascorbate or Fe(II) and to be catalyzed by NADPH-supplemented microsomes.

Sourcerecord Id Scopus 18967