Simone Moretti

Objective: Oxytocin (Oxt) assessment in plasma is challenging, and available data are contradictory. We aimed to assess circulating Oxt in mice by a validated nano-liquid chromatography/mass-spectrometry (nLC-MS/MS) protocol, combined with Oxt hypothalamic expression in different sex, life stages, and in diet-induced obesity. Methods: We assessed plasma Oxt by nLC-MS/MS, Oxt hypothalamic expression by qPCR, and Oxt-immunoreactive neuron and fiber densities by immunohistochemistry and morphometric analyses in C57BL/6 mice at 21 and 60 days of life (p21 and p60, respectively). Mice in normo-fed condition and following 12 weeks of high-fat diet (HFD) were studied alongside food intake and hypothalamic expression of its regulators. Results: Circulating Oxt does not vary based on sex at p21 and p60 but increases with aging. While hypothalamic Oxt mRNA expression followed the same trend across both sexes, Oxt neuron and fiber densities exhibited a similar trend only in females. Plasma vasopressin (Avp) followed Oxt trend in females but was opposite in males and was not mirrored by Avp mRNA hypothalamic expression. HFD-fed females were more resistant to weight gain compared to males and displayed higher Oxt plasma levels and hypothalamic expression. Sex dimorphism in food intake and hypothalamic expression of Avp and of key anorexigenic and orexigenic neuropeptides was detected. Conclusions: Oxt plasma levels are higher in adulthood compared to weaning in mice of both sexes who displayed similar concentrations. Oxt plasma levels are mirrored by Oxt hypothalamic expression. In obesity, females display a lower increase in body weight but higher Oxt plasma levels than males. Significance: This study delineates the pattern of Oxt plasma levels across various age, sex and in obesity in mice. We overcome some limitations of previous research, which were often confounded by numerous factors, by reliably measuring circulating Oxt and integrating this with parallel analyses of Oxt gene expression, and Oxt neuron and immunoreactive fiber densities. Critically, this is among the few studies to employ LC-MS/MS specifically in mice. This novel, integrated perspective is relevant given the compelling evidence for Oxt’s role as an anti-obesity agent and its potential as a therapeutic target. A precise understanding of Oxt regulation in different conditions, backed by reliable methodologies, is indispensable for the rational development of effective treatments for obesity and related endocrine diseases.

In this work, a novel optical–chemical sensor for the detection of per- and polyfluorinated substances (PFASs) in a real scenario is presented. The proposed sensing approach exploits the multimode characteristics of plastic optical fibers (POFs) to achieve unconventional sensors via surface plasmon resonance (SPR) phenomena. The sensor is realized by the coupling of an SPR-POF platform with a novel chemical chip based on different polymeric nanolayers over the core of a D-shaped POF, one made up of an optical adhesive and one of a molecularly imprinted polymer (MIP) for PFAS. The chemical chip is used to launch the light into the SPR D-shaped POF platform, so the interaction between the analyte and the MIP’s sites can be used to modulate the propagated light in the POFs and the SPR phenomena. Selectivity tests and dose–response curves by standard PFOA water solutions were carried out to characterize the detection range sensor response, obtaining a wide PFAS response range, from 1 ppt to 1000 ppt. Then, tests performed on river water samples collected from the Bormida river paved the way for the applicability of the proposed approach to a real scenario.

Sustainable food systems involve the recycling of biowaste and water. This study characterizes thirty-one top soil improvers of anthropogenic, animal, and green waste origin, along with eleven irrigation waters from rivers, channels, and civil wastewater treatment plants (cWWTPs) for the presence of antimicrobials. Liquid chromatography coupled with hybrid High-Resolution Mass Spectrometry (LC-HRMS/MS) was employed to identify forty-eight drugs belonging to the classes of sulfonamides (11), tetracyclines (7), fluoroquinolones (10), macrolides (12), amphenicols (3), pleuromutilins (2), diaminopyrimidines (1), rifamycins (1) and licosamides (1). Sludge from cWWTPs, animal manure, slurry, and poultry litter exhibited the highest loads for sulfonamides, tetracyclines, fluoroquinolones and macrolides (80, 470, 885, and 4,487 ng g^-1 wet weight, respectively) with nor- and ciprofloxacin serving as markers for anthropogenic sources. In compost and digestate, antimicrobials were found to be almost always below the limits of quantification. Reused water from cWWTPs for irrigation in open-field lettuce production were contaminated in the range of 12-221 ng L^-1 with sulfonamides, tetracyclines, and fluoroquinolones, compared to very few detected in channels and surface waters. The Antimicrobials Hazard Index (HI), based on the Predicted No Effect Concentration for Antimicrobial Resistance (PNEC_AMR), was significantly >100 in contaminated topsoil improvers from urban and animal sources. Accounting for worst-case inputs from topsoil improvers and irrigation water, as well as dilution factors in amended soil, fluoroquinolones only exhibited an HI around 1 in open fields for lettuce production. The origin of topsoil improvers plays a pivotal role in ensuring safe and sustainable leafy vegetable production, thereby mitigating the risk of Antimicrobial Resistance (AMR) onset in food-borne diseases and the transfer of AMR elements to the human gut flora.

A quantitative analytical method for PFAS determination in airborne particulate matter (PM) has been developed using liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS), allowing for the determination of 33 compounds. The procedure was applied to ambient PM₁₀ with limits of quantification for PFAS in the fg m⁻³ range. PM₁₀ samples collected during a year-long campaign conducted in an urban site in Umbria (Central Italy) have been characterized for their PFAS content. Among the seven detected PFASs, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) were the most abundant compounds. Furthermore, this work allowed us to obtain the first seasonal trend of airborne PFASs in Central Italy. Seasonal trend analysis shows that PFAS concentration in the atmosphere peaks in summertime. A comparison with trends of other relevant primary and secondary air pollutants determined at the sampling site suggests a secondary nature of the observed PFAS, which are formed in the atmosphere directly from gaseous precursors and can contribute to worsen the urban air quality in summertime.

Untargeted metabolomics is a growing field, in which recent advances in high-resolution mass spectrometry coupled with liquid chromatography (LC-MS) have facilitated untargeted approaches as a result of improvements in sensitivity, mass accuracy, and resolving power. However, a very large amount of data are generated. Consequently, using computational tools is now mandatory for the in-depth analysis of untargeted metabolomics data. This article describes MetAbolomics ReSearch (MARS), an all-in-one vendor-agnostic graphical user interface-based software applying LC-MS analysis to untargeted metabolomics. All of the analytical steps are described (from instrument data conversion and processing to statistical analysis, annotation/identification, quantification, and preliminary biological interpretation), and tools developed to improve annotation accuracy (e.g., multiple adducts and in-source fragmentation detection, trends across samples, and the MS/MS validator) are highlighted. In addition, MARS allows in-house building of reference databases, to bypass the limits of freely available MS/MS spectra collections. Focusing on the flexibility of the software and its user-friendliness, which are two important features in multipurpose software, MARS could provide new perspectives in untargeted metabolomics data analysis.

Poly- and perfluorinated alkyl substances (PFASs) are widely used in the electrical and electronic appliance industry to the point that waste of electrical and electronic equipment (WEEE), also known as e-waste, creates significant potential for PFAS exposure (by inhalation, ingestion, or dermal exposure) for people handling and recycling e-waste. The aim of this work was the development of an untargeted analytical approach in order to detect the presence of possible unknown PFASs in particulate matter collected in three Italian e-waste facilities through liquid chromatography coupled to high-resolution tandem mass spectrometry (LC-HR-MS/MS) in negative ionization mode. By means of three acquisition experiments, nine compounds were detected as candidate PFASs, and three were definitively confirmed by comparison with their authentic standards. Among these, bistriflimide (bis (trifluoromethylsulfonyl) imide), an ionic liquid with several promising technological applications, was the most abundant compound detected in all three recycling plants. This is the first study associating the presence of fluorinated ionic liquids with e-waste, and as these chemicals are not only toxic and persistent but also highly mobile, our results indicate the need to include them in future PFAS research. Only further data on their actual environmental diffusion will determine whether they are emerging pollutants or not.

Sustainable food systems imply the re-use of biowastes and water. In this paper we characterize 30 top soil improvers of anthropogenic, animal and green waste origin, and 11 irrigation waters from rivers, channels, and civil wastewater treatment plants (cWWTPs) for the presence of antimicrobials. Liquid chromatography coupled to hybrid High Resolution Mass Spectrometry (LC-HRMS/MS) was applied to determine 50 different drugs belonging to the classes of sulfonamides (11), tetracyclines (7), fluoroquinolones (10), macrolides (12), amphenicols (3), pleuromutilins (2), diaminopyrimidines (1), rifamycines (1) and lincosamides (1). Biowastes from cWWTPs and animal manure, slurry and litter revealed the highest loads for sulfonamides, tetracyclines, fluoroquinolones, and macrolides (80, 470, 885, and 4,487 ng/g wet weight, respectively) with nor- and cipro-floxacin as marker of anthropogenic sources. In composts and digestates antimicrobials were almost below the determination limits. Re-used waters for irrigation in open field lettuce production resulted contaminated in the range of 12-221 ng/L for sulfonamides, tetracyclines, and fluoroquinolones, against very few detects in channels and surface waters. Antimicrobials Hazard Index (HI) based on Predicted No Effect Concentration for Antimicrobial Resistance (PNEC_AMR) was largely >100 in contaminated top soil improvers from urban and animal sources. Accounting for worst-case inputs from top soil improvers and irrigation water and dilution factors of amended soil, fluoroquinolones only showed a HI around 1 in open fields for lettuce production. The origin of top soil improvers plays a pivotal role for safe and sustainable leafy vegetable productions, to abate the risk of AMR onset in food-borne diseases, as well the transfer of AMR elements to human gut flora.

Tyrosol (T) and hydroxytyrosol (HT) are phenyl alcohol polyphenols with well-recognized health-promoting properties. They are widely diffused in several vegetables, especially in olive products (leaves, fruits and oil). Therefore, they could be present in food produced from herbivorous animals such as in milk and cheese. In this study, an analytical method to determine T, HT and some of their phase II metabolites (sulphates and glucuronides) in cheese was developed and validated. Samples were extracted with an acidic mixture of MeOH/water 80/20 (v/v) and, after a low temperature clean-up, the extracts were evaporated and injected in a liquid-chromatography coupled with high resolution mass spectrometry (LC-Q-Orbitrap). A validation study demonstrated satisfactory method performance characteristics (selectivity, linearity, precision, recovery factors, detection and quantification limits). The developed protocol was then applied to analyze 36 Italian cheeses made from ewe, goat and cow milk. The sum of detected compounds (T, tyrosol sulfate, hydroxytyrosol-3-O-sulfate and hydroxytyrosol-4-O-sulfate) reached as high as 2300 µg kg⁻¹ on a dry weight basis, although in about 45% of cow cheeses it did not exceed 50 µg kg⁻¹. Ewe cheeses were significantly richer of polyphenols (sum) as well as HT sulfate metabolites than cow cheeses. In conclusion, results shows that cheese cannot be considered an important dietary source of these valuable compounds.