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[Display omitted] • CDs were greenly synthesized using mango pulps and subsequently treated with ozone. • The ozone-treated CDs could stabilize the diimine form of oxidized TMB. • A dual-detection platform composed of ozone-treated CDs and TMB was developed. • The platform offered sensitive, selective, and reproducible detection of sarcosine. We synthesized excitation-dependent fluorescent carbon dots (CDs) through a one-pot hydrothermal process using mango pulps as precursors and discovered that the ozone-treated CDs (O 3 -CDs) could stabilize the diimine form of oxidized 3,3′,5,5′-tetramethylbenzidine (diimine oxTMB). A dual-mode colorimetry and ratiometric fluorescence method using O 3 -CDs and TMB as probes was developed for detecting sarcosine. During measurement, sarcosine was selectively oxidized by sarcosine oxidase, and the resulting hydrogen peroxide was catalyzed by horseradish peroxidase to convert TMB into a blue-colored oxidized product. Under acidic conditions, this product was further oxidized to diimine oxTMB, which exhibited an absorbance band at 450 nm. Due to the inner filter effect, the fluorescence emission of O 3 -CDs at 450 nm was significantly quenched by the diimine oxTMB, while the emission at 550 nm was utilized as a reference signal. The dual-mode method selectively detected sarcosine, with detection limits of 0.034 µM and 0.096 µM for colorimetry and ratiometric fluorescence detection, respectively. The ratiometric fluorescence sensing strategy provided a built-in correction to prevent errors originating from environmental variabilities. Moreover, the stabilization of diimine oxTMB mediated by O 3 -CDs improved the detection performance of the method. This study enriches the library of luminescent CDs through the rational utilization of natural biomass and introduces a novel approach to improve the analytical performance of dual-mode detection. [ABSTRACT FROM AUTHOR]

Prostate cancer (PCa) has seriously affected men's quality of life and even endangered their lives. Thus, precise and reliable determination of related biomarkers in clinical samples is extremely important for early diagnosis and treatment of PCa. Sarcosine (Sar) is widely regarded as a potential biomarker for non-invasive diagnosis of PCa owing to its specific high-level expression in the development and metastasis of PCa. With the aid of Ce(III) as a bridge between 4-Methylumbelliferyl Phosphate (4-MUP) and orange emitted carbon dots (o-CDs), here we have constructed a new ratiometric fluorescence sensor for Sar determination by reasonably combining the phosphatase-like activity and complexation reaction characteristics of Ce(IV). This sensor indicates high sensitivity, exceptional selectivity, good reliability, and wide linear range of 0.2–120 μM with a detection limit of 89 nM. Besides, our proposed sensor demonstrates excellent precise and stability even in complex actual urine samples. Interestingly, an inexpensive, portable but reliable smartphone-based microfluidic sensing platform has been fabricated and successfully employed for precise determination of Sar in urine samples, which offers a powerful and convenient tool for the early diagnosis of PCa, and even inspires the research and development of other practical optical sensing devices for cancer home screening. [Display omitted] • Oxidative induction of Ce(III)/Ce(IV) to switch phosphatase like activity and complexation effect. • Construction of ratiometric fluorescence sensor based on 4-MUP/Ce(III)/o-CDs for sarcosine analysis. • Integration of microfluidic chip, 3D-printing device, and smartphone together. • A portable and practical smartphone-based microfluidic sensing platform for PCa early screening. [ABSTRACT FROM AUTHOR]

One of the effective approaches to safeguard human health is the rapid and sensitive identification of food additives, environmental pollutants, and disease markers. This study developed a portable intelligent paper-based sensor for point-of-care detection of hydrogen peroxide (H 2 O 2) and sarcosine (SA) using smartphone colorimetric analysis, supplemented by UV-Vis verification. The paper-based sensor utilizes a chemical modification of conventional filter paper by immobilizing horseradish peroxidase (HRP) from the horseradish plant, achieved through boronate affinity and metal chelation techniques. For H 2 O 2 detection, the sensor exhibited a linear range of 2–100 µmol L−1 and a limit of detection (LOD) of 1.0 µmol L−1. Similarly, a range of 2–400 μmol L−1 for SA detection and an LOD of 1.0 μmol L−1. The sensors were successfully employed for determining the H 2 O 2 concentration in liquor samples, environmental water, and the amount of SA in urine. Significantly, the detection ranges of these sensors surpassed those of commercially available test strips. In summary, we first proposed enzyme-immobilized paper-based sensors for immobilizing HRP from plants to detect H 2 O 2 and SA, which are intelligent, portable, fast, green, low-cost, highly sensitive, and selective, with broad application prospects in food analysis, environmental monitoring, and medical diagnostics. [Display omitted] • An intelligent paper-based sensor for instant colorimetric analysis of H 2 O 2 and sarcosine was successfully prepared. • This sensor is chemically modified on the basis of filter paper and immobilizes HRP from plant horseradish. • This intelligent sensor has the advantages of high sensitivity, strong selectivity, and visualization. • The H 2 O 2 -test paper is suitable for food quality testing, environmental monitoring and early screening of prostate cancer. [ABSTRACT FROM AUTHOR]

Glyphosate-based herbicides (GBH) use has increased drastically over the last decade. This is true especially for potato crops due to their fast harvest cycle and high market demand. In 2015, the World Health Organization (WHO) classified glyphosate and its breakdown product amidomethylphosphonic acid (AMPA) as probably carcinogenic to humans, and it has been reported that these compounds disrupt the ecological and nutritional equilibrium of soils. However, microorganisms with the sarcosine oxidase gene, such as Lysinibacillus sphaericus, can degrade glyphosate through the Carbon-Phosphorus (C-P) pathway without leading to AMPA production. The aim of this study was to evaluate the addition of the plant growth-promoting bacteria (PGPB) L. sphaericus as a bioremediation agent in a potato crop sprayed with a GBH, in conjunction with the nitrogen fixation activity mediated by the bacteria. To that end, a GBH solution was used to treat a potato field, and different treatments (glyphosate (G), bacteria (B), bacteria+glyphosate (BG), and negative control (C)) were evaluated by measuring the glyphosate, AMPA, nitrates, and ammonium concentrations. BG treatment showed a 79% reduction of glyphosate concentration in soil, leading to minimal AMPA production, compared to the 23% reduction observed after G treatment. Furthermore, the ammonium concentrations were significantly higher in samples treated with BG and in C samples (p < 0.005). Therefore, we propose the addition of L. sphaericus as a good bioremediation strategy for soils sprayed with GBH.

Abstract: Objective: Augmentation of sarcosine, a natural inhibitor of the glycine transporter type I, normalizes glutamatergic neurotransmission, having beneficial impact on primary negative symptoms in schizophrenia and may also influence immune system and interleukin 6 (IL‐6) levels. Aim: Finding a relationship between initial IL‐6 serum concentrations or its changes and severity of symptoms as a result of sarcosine addition to stable antipsychotic treatment. Method: Fifity‐eight individuals with schizophrenia with predominantly negative symptoms completed a 6‐month randomized, double‐blind placebo‐controlled prospective study. Patients received 2 g of sarcosine (n = 29) or placebo (n = 30) daily per os. We measured IL‐6 levels and severity of symptoms at the beginning, after 6 weeks and 6 months. As main clinical tools, we used Positive and Negative Syndrome Scale (PANSS) and Calgary depression scale for schizophrenia (CDSS). Results: Augmentation with sarcosine had no effect on IL‐6 serum levels in all time points. We noted significant improvements in negative symptoms, general psychopathology, and total PANSS score in the sarcosine group. We found correlation of initial serum IL‐6 with severity of positive symptoms and negative association between IL‐6 levels reduction and positive symptoms reduction. Conclusions: Sarcosine does not significantly affect IL‐6 concentrations but IL‐6 may be involved in mechanisms related to the presence of positive symptoms. [ABSTRACT FROM AUTHOR]

Shortly after sarcosine was delineated as a potential biomarker for prostate cancer in 2009, a variety of analytical methods for clinical application were developed. Moreover, higher uptake of glycine in the mitochondria also played a role in cancer proliferation. A major constraint in the accurate quantification of sarcosine was the interference of the two isomers, a-alanine and ß-alanine, using chromatographic separation techniques. Accordingly, we aimed to develop an analytical method for determining sarcosine and its related metabolites (a- and ß-alanine, glycine and creatinine) under the same conditions by gas chromatography-tandem mass spectrometry (GCMS/MS). BSTFA + 1% TMCS was used for silylation, and GC-MS/MS conditions were optimized for the target analytes. The unique transition ions of sarcosine, a- and ß-alanine, glycine and creatinine set up in MRM acquisition were m/z 116 → 73, 190 → 147, 176 → 147, 176 → 147 and 100 → 73, respectively. This newly developed method was successfully validated to apply in clinical settings with low limits of detection (0.01 - 0.03 µg•mL-1), high correlations (R2 > 0.99), great accuracy (88 - 110% recovery), and notable precision (RSD < 10%). All TMS derivatives were > 80% stable for up to 2 h after derivatization and analyzing during this period promises to achieve an accurate result. Monitoring the five-substance profile could enhance prospects for early diagnosis of prostate cancer. [ABSTRACT FROM AUTHOR]

An enzyme-coupled colorimetric assay for quantification of urinary sarcosine was developed. The proposed method is a specific reaction based on hydrogen peroxide (H2O2) formation via sarcosine oxidase (SOX). The liberated H2O2 reacts with Amplex Red in the presence of horseradish peroxidase (HRP) to produce the redfluorescent oxidation product, resorufin, which can be measured spectrophotometrically (OD570). The method was performed in the 96-well microtiter plate. Reaction conditions, such as pH and reaction time were optimized. At the optimum conditions, the limit of detection (LOD) and quantification (LOQ) were found to be 0.7 and 1 µM, respectively. A good linearity was revealed with a coefficient of 0.990. The assay showed no significant interference from ascorbic acid, glucose and bilirubin. In addition, it is extremely specific for sarcosine rather than other amino acids. The determination of sarcosine in human urine displayed high accuracy and good reproducibility. This method is promising to differentiate prostate cancer patients from healthy subjects according to urinary sarcosine level. Altogether, this study provides a rapid, simple and specific tool to determine urinary sarcosine which could be useful for prostate cancer diagnosis. [ABSTRACT FROM AUTHOR]

This work investigated the preparation of chitosan nanoparticles used as carriers for doxorubicin for targeted cancer delivery. Prepared nanocarriers were stabilized and functionalized via zinc ions incorporated into the chitosan nanoparticle backbone. We took the advantage of high expression of sarcosine in the prostate cancer cells. The prostate cancer targeting was mediated by the AntiSar antibodies decorated surface of the nanocage. Formation of the chitosan nanoparticles was determined using a ninhydrin assay and differential pulse voltammetry. Obtained results showed the strong effect of tripolyphosphine on the nanoparticle formation. The zinc ions affected strong chitosan backbone coiling both in inner and outer chitosan nanoparticle structure. Zinc electrochemical signal depended on the level of the complex formation and the potential shift from -960 to -950 mV. Formed complex is suitable for doxorubicin delivery. It was observed the 20% entrapment efficiency of doxorubicin and strong dependence of drug release after 120 min in the blood environment. The functionality of the designed nanotransporter was proven. The purposed determination showed linear dependence in the concentration range of Anti-sarcosine IgG labeled gold nanoparticles from 0 to 1000 μg/mL and the regression equation was found to be y = 3.8x - 66.7 and R2 = 0.99. Performed ELISA confirmed the ability of Anti-sarcosine IgG labeled chitosan nanoparticles with loaded doxorubicin to bind to the sarcosine molecule. Observed hemolytic activity of the nanotransporter was 40%. Inhibition activity of our proposed nanotransporter was evaluated to be 0% on the experimental model of S. cerevisiae. Anti-sarcosine IgG labeled chitosan nanoparticles, with loaded doxorubicin stabilized by Zn ions, are a perspective type of nanocarrier for targeted drug therapy managed by specific interaction with sarcosine and metallothionein for prostate cancer. [ABSTRACT FROM AUTHOR]

For the first time, arylmethylidene cyclohexanones that are non-symmetrical due to the presence of peripheral substituents were studied in 1,3-dipolar cycloaddition reactions. It is shown that the interaction with the azomethine ylide generated from sarcosine proceeds regio- and diastereoselectively, with the participation of two non-equivalent parts of the dipolarophile. Also for the first time, β-amino ketones (Mannich bases) were used as dipolarophile equivalents of unsaturated ketones. It was found that cycloaddition occurs diastereoselectively at the generated center. [ABSTRACT FROM AUTHOR]

Alcohol-initiated ring-opening polymerization (ROP) of cyclic esters for synthesizing polyesters was well established, but amine-initiated ROP of cyclic esters was rare. A challenge is slow initiation and fast propagation in the amine-initiated ROPs. To address the difficulties, an ionic H-bond donor (iHBD) and H-bond acceptor (HBA) binary organocatalysis in amine-initiated ROP of lactide (LA) was developed. Guanidinium hexahydro-2 H -pyrimido[1,2- a ] pyrimidin-1-ium [(HppH 2 ) + ] and tertiary amine sparteine (SP), cooperatively played the role of iHBD/HBA binary catalysts, efficiently promoted ROP of LA from amine initiators toward polylactide (PLA) and polysarcosine- block -polylactide diblock copolymer (PSar- b -PLA). Benzyl amine and N -methylbenzylamine initiated ROPs of LA under mild conditions produced PLAs with predictable molecular weights ( M n,NMR  = 2.9–17.1 kg mol −1 ) and narrow dispersities ( Ð M,SEC  = 1.13–1.23). Macroinitiator PSar copolymerized with LA under the iHBD/HBA catalysis, producing PSar- b -PLAs with controlled molecular weights ( M n,NMR  = 5.7–14.8 kg mol −1 ) and low dispersities ( Ð M,SEC  = 1.16–1.21). Kinetics and chain extension experiments confirmed that the amine-initiated ROP of LA in presence of (HppH 2 ) + BF 4 − /SP was in controlled/living manner. 1 H NMR, 13 C NMR, SEC, and MALDI-ToF MS analyses indicated that the obtained PLA was exclusively initiated from the corresponding amine with amide linkage. An iHBD/HBA binary activation mechanism was proposed. [ABSTRACT FROM AUTHOR]

Background: Left atrial appendage (LAA) closure (LAAC) by implantation of an occlusion device is an established cardiac intervention to reduce risk of stroke while avoiding intake of oral anticoagulation medication during atrial fibrillation. Cardiac interventions can alter local or systemic gene and protein expression. Effects of LAAC on systemic metabolism have not been studied yet. Objectives: We aimed to study the effects of interventional LAAC on systemic metabolism. Methods: Products of glycolysis, tricarboxylic acid and urea metabolism were analyzed by ESI-LC-MS/MS and MS/MS using the AbsoluteIDQ™ p180 Kit in plasma of 44 patients undergoing successful interventional LAAC at baseline (T0) and after 6 months (T1). Results: During follow up, plasma concentrations of several parameters of glycolysis and tricarboxylic acid cycle (TCA) and urea metabolism increased (alanine, hexose, proline, sarcosine), while others decreased (aspartate, glycine, SDMA, serine). Multivariate linear regression analysis showed that time after interventional LAAC was an independent predictor for metabolite changes, including the decrease of SDMA (beta −0.19, p < 0.01) and the increase of sarcosine (beta 0.16, p < 0.01). Conclusions: Successful interventional LAAC affects different pathways of the metabolome, which are probably related to cardiac remodeling. The underlying mechanisms as well as the long term effects have to be studied in the future. [ABSTRACT FROM AUTHOR]

In this work, physical properties such as density, refractive index and viscosity of aqueous diethanolamine sarcosinate (DEA-SAR) solution were measured at different temperatures. The knowledge of physical properties is necessary for the process design and simulation of acid gas absorber plant. Various concentrations of aqueous DEA-SAR solutions (0.05, 0.10, 0.15, 0.20, 0.25 and 0.30) were investigated at temperature ranging from 298.15 to 333.15 K. The reported results showed an increment behavior in the physical properties with the increase in concentration isothermally, and a decreasing one with the rise in temperature of the solution at any given concentration. Empirical models were applied to correlate the experimental data of each physical property as a function of both concentration and temperature. A quantitative analysis of variation was carried out for estimating the significance of the physical property's data. [ABSTRACT FROM AUTHOR]

Abstract: Microsolvation of neutral and zwitterionic conformations of sarcosine is explored at ωB97XD/6‐311++G(d,p) level. Natural Bond Orbital and Boltzman population results are used to show the importance of the methyl group in sarcosine. Various configurations have been considered to locate the low lying configuration of sarcosine (neutral and zwitterionic forms) with one to four water molecules. The various sarcosine‐(water)1‐4 clusters have been analyzed with the established hydrogen bonding networks. The current findings revealed that one water molecule is enough to stabilize the zwitterionic form of sarcosine. Additionally, the higher number of water molecules interacting with Sarcosine shows that neutral and zwitterionic tautomers of sarcosine attained the isoenergetic with four water molecules. [ABSTRACT FROM AUTHOR]

The use of amino acids as potential solvents for carbon dioxide (CO 2 ) capture has been considered by a number of researchers. However, very little is known about the kinetics and mechanism of amino acids-CO 2 reactions. In this work, we investigate the reactions of three amino acids ( l -Arginine, Glycine and Sarcosine) with CO 2 in aqueous media using stopped-flow conductivity technique. The experiments were performed at temperatures between 293 and 313 K and amino acids concentrations were in the range of 0.05–0.2 molar. The overall rate constants (k ov ) was found to increase with increased amino acid concentration and solution temperature. Both zwitterion and termolecular mechanisms were used to model and interpret the data. However, the Zwitterion mechanism was found to be the preferred one. From the stopped-flow results at pH around 6, we found that neutral l -Arginine, Glycine and Sarcosine react with CO 2 (aq) with k (M −1 s −1 ) = 2.81 × 10 10 exp( − 4482.9 T ( K ) ), k (M −1 s −1 ) = 3.29 × 10 13 exp( − 8143.7 T ( K ) ) and k (M −1 s −1 ) = 3.90 × 10 13 exp( − 7991.0 T ( K ) ) respectively. The corresponding activation energies are 37.28 kJ mol −1 , 67.71 kJ mol −1 And 66.44 kJ mol −1 respectively. A comparison between the kinetics of the three amino acids showed that Arginine exhibits highest reaction rate with CO 2 followed by Sarcosine and then Glycine. The technique and results obtained from this work can be used as strong tools in the development of efficient new solvents for the removal of CO 2 from flue and industrial gases. [ABSTRACT FROM AUTHOR]

Sarcosine is an N-methyl derivative of the amino acid glycine, and its elevation in tissues and physiological fluids of patients with sarcosinemia could reflect a deficient pool size of activated 1-carbon units. Sarcosinemia is a rare inherited metabolic condition associated with mental retardation. In the present study, we investigated the acute effect of sarcosine and/or creatine plus pyruvate on some parameters of oxidative stress and energy metabolism in cerebral cortex homogenates of 21-day-old Wistar rats. Acute administration of sarcosine induced oxidative stress and diminished the activities of adenylate kinase, GAPDH, complex IV, and mitochondrial and cytosolic creatine kinase. On the other hand, succinate dehydrogenase activity was enhanced in cerebral cortex of rats. Moreover, total sulfhydryl content was significantly diminished, while DCFH oxidation, TBARS content, and activities of SOD and GPx were significantly enhanced by acute administration of sarcosine. Co-administration of creatine plus pyruvate was effective in the prevention of alterations provoked by sarcosine administration on the oxidative stress and the enzymes of phosphoryltransfer network. These results indicate that acute administration of sarcosine may stimulate oxidative stress and alter the energy metabolism in cerebral cortex of rats. In case these effects also occur in humans, they may contribute, along with other mechanisms, to the neurological dysfunction of sarcosinemia, and creatine and pyruvate supplementation could be beneficial to the patients. [ABSTRACT FROM AUTHOR]

In this article we report on the development and optimization of a biomimetic sensor for the label-free detection of the amino acid sarcosine, a molecule which is seen as a biomarker for prostate cancer. The recognition elements were sarcosine-imprinted poly-aminothiophenol ( p -ATP) layers deposited by electro-polymerization onto screen-printed gold electrodes and, for comparison, onto carbon electrodes covered first with a gold-nanoparticles interlayer. Using the latter type of electrodes, we reached a detection limit below 1 nM in aqueous buffer solutions with an accessible concentration range from the nano- to the micromolar scale. This was achieved by a careful thickness optimization of the Au-nanoparticle and the p -ATP layers in combination with Faradaic impedance spectroscopy as a readout method. The sensor showed an excellent reproducibility, a good stability with time, and a surprisingly low cross-selectivity towards other proteins. [ABSTRACT FROM AUTHOR]

Objectives: Regular aerobic exercise provides beneficial effects on human health and reduces all-cause mortality. Aerobic exercise has profound metabolic effects, and specific metabolites may reflect physiological changes. We aimed to identify endogenous metabolites that distinguish the trained from the untrained state to increase the spectrum of analytes amenable for hypothesis testing and to expand understanding of putative beneficial pathways.Design: Cross sectional laboratory repeated measures study.Methods: Exercise testing was performed in 37 healthy male participants and serum samples were obtained before and after completion of a ten-week standardized exercise program. Samples were analyzed for routine clinical parameters and for 188 endogenous metabolites by LC-MS/MS.Results: Indicating the effectiveness of the intervention program, parameters of sport physiology were different after training. After correcting for multiple testing, serum concentrations of several metabolites differed between the trained and untrained state. Serine and glutamate decreased in response to exercise, whereas sarcosine and kynurenine increased. Phosphatidylcholines showed a mixed response in that four species increased and three decreased. However, all seven lysophosphatidylcholines and all four plasmalogens that differed between the trained and untrained state, increased. One short-chain acylcarnitine also decreased. In receiver operator characteristics analyses, sarcosine displayed the highest AUC value (0.839; 95% CI: 0.734-0.926) in discriminating the pre- from the post-trained state.Conclusions: Our study detected metabolites that clearly differentiate the trained from the untrained state. These metabolites may be targeted in mechanistic studies to understand underlying biochemical pathways and could serve to improve the design, monitoring and individualization of training programs. [ABSTRACT FROM AUTHOR]

Adsorption characteristics of N -methylglycine (Sar) on silver surface was investigated based on density functional theory and surface enhanced Raman spectroscopy (SERS) technique. The Sar was characterized by powder X-ray diffraction (XRD) and dynamic light scattering techniques. AgNPs were prepared by solution combustion method using urea as fuel. The AgNPs were characterized by XRD and high-resolution transmission electron microscopic techniques. The structural parameters of Sar molecule were compared with the reported experimental XRD values. The change in structural parameters of Sar after adsorption on silver surface shows the interaction between Sar and silver cluster. Raman frequencies were calculated for Sar, Sar adsorbed on silver surface and their corresponding spectra were studied experimentally. The conventional Raman and SERS frequencies were compared with the experimental values and analyzed on the basis of potential energy distribution calculation. Natural bond orbital analysis was carried out to investigate the intra-molecular stabilization interactions, which confirms the bioactivity of the molecule. Frontier molecular orbital analysis was carried out for Sar and Sar adsorbed on silver surface. The reduced band gap value was observed for Sar after adsorption on silver surface. The reduction in band gap indicates the intermolecular charge transfer, which leads to the bioactivity of the title molecule. SERS spectral analysis shows that the Sar adsorbed as stand-on orientation on the silver surface. [ABSTRACT FROM AUTHOR]

Indicator displacement assay plays a fundamental role in the development of chemosensors. We explored here an ingenious yet effective strategy for amperometric assay of electrochemically inactive sarcosine based on an indicator displacement principle, in which 1,2-naphthoquinone-4-sulphonic acid sodium salt (NQS) was proposed as the receptor and the electroactive Ru(NH 3 ) 6 3+ cations used as an indicator. Due to the stronger binding affinity of the NQS toward sarcosine than toward Ru(NH 3 ) 6 3+ , the developed amperometric indicator displacement assay (A-IDA) exhibits high selectivity and excellent sensitivity toward sarcosine determination as well as with a lower detection limit (30.00 nM, S/N =3). [ABSTRACT FROM AUTHOR]

The present article details the formation of calcium hydroxyapatite synthesized by the hydrothermal way, in presence of glycine or sarcosine. The presence of these amino-acids during the synthetic processes reduces the crystalline growthing through the formation of hybrid organic-inorganic species The crystallite sizes are decreasing and the morphology is modified with the increase of the amino-acid concentration. [ABSTRACT FROM AUTHOR]

A series of novel spirooxindolopyrrolidine derivatives has been prepared via a three-component 1,3-dipolar cycloaddition reaction of 2-oxindoleazomethine ylides generated in situ from isatin and sarcosine or valine with ( E)-3-aryl-2-cyanoacrylamides or ( E)-3-aryl-2-(4-arylthiazol-2-yl)acrylonitriles as dipolarophiles. To rationalize the observed regio- and stereoselectivity, calculations of the geometrical structures of all possible conformers and charge distribution in the reacting systems were performed. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Fe 3 O 4 @SiO 2 @NiCo 2 S 4 has both superior oxidase activity and peroxidase activity. • The Fe 3 O 4 @SiO 2 @NiCo 2 S 4 has good recyclability. • Fe 3 O 4 @SiO 2 @NiCo 2 S 4 can be employed to the detection of ascorbic acid and sarcosine. • A sensitive, simple and specific colorimetric detection tool has been designed. In this paper, Fe 3 O 4 @SiO 2 @NiCo 2 S 4 nanocomposite catalytic materials were prepared using a low eutectic solvent and hydrothermal method. Characterization was performed using scanning electron microscopy, transmission electron micrographs, X-ray photoelectron spectra, X-ray diffraction, Zeta potential and Fourier transform infrared spectrometry, and Vibrating sample magnetometry. The catalytic mechanism was verified by Electron Paramagnetic Resonance experiments. Several assay platforms were established based on their different enzyme activities. Based on the oxidase-like activity, a colorimetric sensing assay for ascorbic acid was developed with a linear range and detection limit of 1–200 µM and 0.36 µM, respectively. Sarcosine can be effectively quantified by utilizing its peroxidase-like activity. The linear range of sarcosine assay was 1.25–350 µM with a detection limit of 0.42 µM. Notably, Fe 3 O 4 @SiO 2 @NiCo 2 S 4 exhibited reusability and high precision in quantifying sarcosine in human urine samples. The nanomaterials could be easily and quickly separated from the reaction system using a magnet for future use due to their superior magnetic properties. Therefore, the colorimetric sensing analytical method established in this study provided a new strategy for the detection of ascorbic acid in food matrices and serum samples as well as sarcosine in urine samples. The developed method also provided a potential application of composite and bimetallic materials in the fields of food detection, bioanalysis, and clinical disease diagnosis. [ABSTRACT FROM AUTHOR]

One-carbon (C1) substrates, such as methanol or formate, are attractive feedstocks for circular bioeconomy. These substrates are typically converted into formaldehyde, serving as the entry point into metabolism. Here, we design an erythrulose monophosphate (EuMP) cycle for formaldehyde assimilation, leveraging a promiscuous dihydroxyacetone phosphate dependent aldolase as key enzyme. In silico modeling reveals that the cycle is highly energy-efficient, holding the potential for high bioproduct yields. Dissecting the EuMP into four modules, we use a stepwise strategy to demonstrate in vivo feasibility of the modules in E. coli sensor strains with sarcosine as formaldehyde source. From adaptive laboratory evolution for module integration, we identify key mutations enabling the accommodation of the EuMP reactions with endogenous metabolism. Overall, our study demonstrates the proof-of-concept for a highly efficient, new-to-nature formaldehyde assimilation pathway, opening a way for the development of a methylotrophic platform for a C1-fueled bioeconomy in the future., (© 2023. The Author(s).)

Aim: To quantify the association between serum sarcosine and diabetic retinopathy (DR) using weighted gene co-expression network analysis (WGCNA)., Methods: We measured serum metabolites in 69 pairs of type 2 diabetes (T2D) patients with and without DR matched by age, gender, body mass index（BMI and HbA1c, using a propensity score matching-based approach. To identify modules and metabolites linked to DR, pathway analysis was performed using WGCNA, the Kyoto Encyclopedia of Genes and Genomes and Small-Molecule Pathway Database. The association of sarcosine with DR was estimated by restricted cubic spline and conditional logistic regression models. Its joint effects with covariates on DR were also extensively examined., Results: With per interquartile range elevation of sarcosine, the adjusted odds ratio (AOR) of DR significantly decreased by 67% (AOR: 0.33, 95% confidence interval [CI]: 0.19-0.58). Similar results were also found in the tertile analysis. Compared with those in the first tertile of sarcosine, the AOR significantly decreased by 54% (AOR: 0.46, 95% CI: 0.18-1.17) and 78% (AOR: 0.22, 95% CI: 0.08-0.59) for subjects in the second and third tertiles, respectively. Compared with subjects with lower sarcosine and lower HDL-C levels, those with higher sarcosine and lower HDL-C levels had the lowest odds of DR (OR: 0.13, 95% CI: 0.04, 0.43)., Conclusions: Serum sarcosine was inversely related to DR, especially in T2D patients with insufficient HDL-C. This study provides insights on a possible novel target for DR precision prevention and control, as well as a better understanding of the DR mechanism., (© 2023 John Wiley & Sons Ltd.)

Glycine-rich proteins (GRPs) containing a high content of glycine residues (>30%) possess unique structural stability. However, the controllable synthesis of glycine-rich poly(amino acid)s (PAAs) to mimic GRPs has not been realized yet due to the poor solubility of polyglycine segments. We developed a novel method to synthesize glycine-rich PAAs via the controlled ring-opening copolymerization of glycine- N -thiocarboxyanhydrides (Gly-NTA) with sarcosine- N -carboxyanhydride and ε-Cbz-l-lysine- N -carboxyanhydride. The random copolymerization is evidenced by a kinetic study that shows that the propagation rate constant of Gly-NTA is close to those of comonomers. The copolymers exhibit predictable molecular weights between 4.5 and 24.6 kg/mol and tunable glycine incorporation, varying from 10.3 to 59.2%. Poly(Gly- r -Sar) samples with various glycine contents form nanoparticles or a hydrogel in water. Remarkably, the β-sheet folding of poly(Gly- r -Lys) remains intact in a neutral environment where the amine groups are protonated. Overall, the strategy paves the way to engineer glycine-rich PAAs and thereby expands their applications.

Background: The morbidity of cancer keeps growing worldwide, and among that, the colorectal cancer (CRC) has jumped to third. Existing early screening tests for CRC are limited. The aim of this study was to develop a diagnostic strategy for CRC by plasma metabolomics., Methods: A targeted amino acids metabolomics method was developed to quantify 32 plasma amino acids in 130 CRC patients and 216 healthy volunteers, to identify potential biomarkers for CRC, and an independent sample cohort comprising 116 CRC subjects, 33 precancerosiss patients and 195 healthy volunteers was further used to validate the diagnostic model. Amino acids-related genes were retrieved from Gene Expression Omnibus and Molecular Signatures Database and analyzed., Results: Three were chosen out of the 32 plasma amino acids examined. The tryptophan / sarcosine / glutamic acid -based receiver operating characteristic (ROC) curve showed the area under the curve (AUC) of 0.955 (specificity 83.3% and sensitivity 96.8%) for all participants, and the logistic regression model were used to distinguish between early stage (I and II) of CRC and precancerosiss patients, which showed superiority to the commonly used carcinoembryonic antigen. The GO and KEGG enrichment analysis proved many alterations in amino acids metabolic pathways in tumorigenesis., Conclusion: This altered plasma amino acid profile could effectively distinguish CRC patients from precancerosiss patients and healthy volunteers with high accuracy. Prognostic tests based on the tryptophan/sarcosine/glutamic acid biomarkers in the large population could assess the clinical significance of CRC early detection and intervention., (© 2023. The Author(s).)

N-methyl-glycine (sarcosine) is known to promote metastatic potential in some cancers; however, its effects on bladder cancer are unclear. T24 cells derived from invasive cancer highly expressed GNMT, and S-adenosyl methionine (SAM) treatment increased sarcosine production, promoting proliferation, invasion, anti-apoptotic survival, sphere formation, and drug resistance. In contrast, RT4 cells derived from non-invasive cancers expressed low GNMT, and SAM treatment did not produce sarcosine and did not promote malignant phenotypes. In T24 cells, the expression of miR-873-5p, which suppresses GNMT expression, was suppressed, and the expression of ERVK13-1, which sponges miR-873-5p, was increased. The growth of subcutaneous tumors, lung metastasis, and intratumoral GNMT expression in SAM-treated nude mice was suppressed in T24 cells with ERVK13-1 knockdown but promoted in RT4 cells treated with miR-873-5p inhibitor. An increase in mouse urinary sarcosine levels was observed to correlate with tumor weight. Immunostaining of 86 human bladder cancer cases showed that GNMT expression was higher in cases with muscle invasion and metastasis. Additionally, urinary sarcosine concentrations increased in cases of muscle invasion. Notably, urinary sarcosine concentration may serve as a marker for muscle invasion in bladder cancer; however, further investigation is necessitated.

Sarcosine (N-methylglycine), a glutamatergic modulator, reduces the primary negative symptoms of schizophrenia. These beneficial changes might be mediated by trophic factors such as epidermal growth factor (EGF). We assessed associations between initial serum EGF levels or changes in serum EGF levels and symptom severity during the addition of sarcosine to stable antipsychotic treatment and thereby evaluated the associations between glutamatergic modulation, clinical changes and peripheral EGF concentrations. Fifty-eight subjects with a diagnosis of chronic schizophrenia with dominant negative symptoms, stably treated with antipsychotics, completed a prospective 6-month, randomized, double-blind, placebo-controlled study. Subjects received orally 2 g of sarcosine ( n = 28) or placebo ( n = 30) daily. Serum EGF levels and symptom severity (using the Positive and Negative Syndrome Scale (PANSS) and the Calgary Depression Scale for Schizophrenia (CDSS)) were assessed at baseline, 6-week and 6-month follow-up. Augmentation antipsychotic treatment with sarcosine had no effect on EGF serum levels at any time points. Only the sarcosine group showed a significant improvement in negative symptoms, general psychopathology subscales and the overall PANSS score. We found a reduction in serum EGF levels in the placebo group, but levels in the sarcosine remained stable during the study. Our data indicate that improvement in negative symptoms due to sarcosine augmentation is not directly mediated by EGF, but effective treatment may induce the production or block the decrease in EGF concentrations, which indicates the neuroprotective effect of treatment and confirms the relationship between neuroprotection and EGF levels.

Heat stress (HS) impairs productivity, health, and welfare in dairy cows, and additionally causes metabolic changes. Hence, specific metabolites could be used as HS biomarkers. Consequently, the aim of the present study was to compare blood metabolite concentrations of German Holstein dairy cows and of their female calves suffering from high temperature-humidity index (THI) during late gestation (cows) or during their first week of life (calves) or not. According to the mean daily THI (mTHI) at the day before blood sampling, animals were classified into 2 groups: high mTHI ≥60 (hmTHI) and low mTHI <60 (lmTHI). To perform a standard cross-sectional 2-group study, cow groups (n = 48) and calf groups (n = 47) were compared separately. Differences in metabolite concentrations between hmTHI and lmTHI animals were inferred based on a targeted metabolomics approach. In the first step, processed metabolomics data were evaluated by multivariate data analysis techniques, and were visualized using the web-based platform MetaboAnalyst V5.0. The most important metabolites with pronounced differences between groups were further analyzed in a second step using linear mixed models. We identified 9 thermally sensitive metabolites for the cows [dodecanedioic acid; 3-indolepropionic acid; sarcosine; triglycerides (14:0&#95;34:0), (16:0&#95;38:7), (18:0&#95;32:1), and (18:0&#95;36:2); phosphatidylcholine aa C38:1; and lysophosphatidylcholine a C20:3] and for the calves [phosphatidylcholines aa C38:1, ae C38:3, ae C36:0, and ae C36:2; cholesteryl esters (17:1) and (20:3); sphingomyelins C18:0 and C18:1; and p-cresol sulfate], most of them related to lipid metabolism. Apart from 2 metabolites (3-indolepropionic acid and sarcosine) in cows, the metabolite plasma concentrations were lower in hmTHI than in lmTHI groups. In our heat-stressed dry cows, results indicate an altered lipid metabolism compared with lactating heat-stressed cows, due to the missing antilipolytic effect of HS. The results also indicate alterations in lipid metabolism of calves due to high mTHI in the first week of life. From a cross-generation perspective, high mTHI directly before calving seems to reduce colostrum quality, with detrimental effects on metabolite concentrations in offspring., (The Authors. Published by Elsevier Inc. and Fass Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)