Histamine signaling and metabolism identify potential biomarkers and therapies for lymphangioleiomyomatosis

Biomarcador; Histamina; LimfangioleiomiomatosiBiomarcador; Histamina; LinfangioleiomiomatosisBiomarker; Histamine; LymphangioleiomyomatosisInhibition of mTOR is the standard of care for lymphangioleiomyomatosis (LAM). However, this therapy has variable tolerability and some patients show progressive decline of lung function despite treatment. LAM diagnosis and monitoring can also be challenging due to the heterogeneity of symptoms and insufficiency of non-invasive tests. Here, we propose monoamine-derived biomarkers that provide preclinical evidence for novel therapeutic approaches. The major histamine-derived metabolite methylimidazoleacetic acid (MIAA) is relatively more abundant in LAM plasma, and MIAA values are independent of VEGF-D. Higher levels of histamine are associated with poorer lung function and greater disease burden. Molecular and cellular analyses, and metabolic profiling confirmed active histamine signaling and metabolism. LAM tumorigenesis is reduced using approved drugs targeting monoamine oxidases A/B (clorgyline and rasagiline) or histamine H1 receptor (loratadine), and loratadine synergizes with rapamycin. Depletion of Maoa or Hrh1 expression, and administration of an L-histidine analog, or a low L-histidine diet, also reduce LAM tumorigenesis. These findings extend our knowledge of LAM biology and suggest possible ways of improving disease management.This research was supported by AELAM, The LAM Foundation (Seed Grant 2019), Instituto de Salud Carlos III grants PI15/00854, PI18/01029, and ICI19/00047 (co-funded by European Regional Development Fund (ERDF), a way to build Europe), Generalitat de Catalunya SGR grants 2014-364 and 2017-449, the CERCA Program, and ZonMW-TopZorg grant 842002003. C.L.M. acknowledges the financial support (PRA-2017-51 project) of the University of Pisa. A.U.K. is supported by Nottingham Trent University’s Independent Fellowship Scheme

Pathway-specific effects of ADSL deficiency on neurodevelopment

Adenylosuccinate lyase (ADSL) functions in de novo purine synthesis (DNPS) and the purine nucleotide cycle. ADSL deficiency (ADSLD) causes numerous neurodevelopmental pathologies, including microcephaly and autism spectrum disorder. ADSLD patients have normal serum purine nucleotide levels but exhibit accumulation of dephosphorylated ADSL substrates, S-Ado, and SAICAr, the latter being implicated in neurotoxic effects through unknown mechanisms. We examined the phenotypic effects of ADSL depletion in human cells and their relation to phenotypic outcomes. Using specific interventions to compensate for reduced purine levels or modulate SAICAr accumulation, we found that diminished AMP levels resulted in increased DNA damage signaling and cell cycle delays, while primary ciliogenesis was impaired specifically by loss of ADSL or administration of SAICAr. ADSL-deficient chicken and zebrafish embryos displayed impaired neurogenesis and microcephaly. Neuroprogenitor attrition in zebrafish embryos was rescued by pharmacological inhibition of DNPS, but not increased nucleotide concentration. Zebrafish also displayed phenotypes commonly linked to ciliopathies. Our results suggest that both reduced purine levels and impaired DNPS contribute to neurodevelopmental pathology in ADSLD and that defective ciliogenesis may influence the ADSLD phenotypic spectrum.ID was funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no. 754510, THS, JL, and SP were funded by the Ministry of Science, Innovation and Universities (MCIU; PGC2018-095616-B-I00 to THS, PGC2018-099562-B-I00 to JL, and BFU2017-83562-P to SP), the 2017 SGR 1089 (AGAUR), FEDER, the Centres of Excellence Severo Ochoa award, and the CERCA Programme. THS was supported by the NIH Intramural Research Program, National Cancer Institute, Center for Cancer Research. MP was funded by grants from the Deutsche Forschungsgemeinschaft (DFG PH144/4-1 and PH144/6-1). MZ, OS, and VS were supported by Charles University, program PROGRES Q26/LF1. We would like to thank Biocev, First Faculty of Medicine, Charles University, for the opportunity to use their department’s equipment

Divergent Effects of Glycemic Control and Bariatric Surgery on Circulating Concentrations of TMAO in Newly Diagnosed T2D Patients and Morbidly Obese

High circulating concentrations of the gut microbiota-derived metabolite trimethylamine N-oxide (TMAO) are significantly associated with the risk of obesity and type 2 diabetes (T2D). We aimed at evaluating the impact of glycemic control and bariatric surgery on circulating concentrations of TMAO and its microbiota-dependent intermediate, γ-butyrobetaine (γBB), in newly diagnosed T2D patients and morbidly obese subjects following a within-subject design. Based on HbA1c concentrations, T2D patients achieved glycemic control. However, the plasma TMAO and γBB concentrations were significantly increased, without changes in estimated glomerular filtration rate. Bariatric surgery was very effective in reducing weight in obese subjects. Nevertheless, the surgery reduced plasma γBB concentrations without affecting TMAO concentrations and the estimated glomerular filtration rate. Considering these results, an additional experiment was carried out in male C57BL/6J mice fed a Western-type diet for twelve weeks. Neither diet-induced obesity nor insulin resistance were associated with circulating TMAO and γBB concentrations in these genetically defined mice strains. Our findings do not support that glycemic control or bariatric surgery improve the circulating concentrations of TMAO in newly diagnosed T2D and morbidly obese patients

Role of the Transforming Growth Factor-β in regulating hepatocellular carcinoma oxidative metabolism.

Transforming Growth Factor beta (TGF-β) induces tumor cell migration and invasion. However, its role in inducing metabolic reprogramming is poorly understood. Here we analyzed the metabolic profle of hepatocellular carcinoma (HCC) cells that show diferences in TGF-β expression. Oxygen consumption rate (OCR), extracellular acidifcation rate (ECAR), metabolomics and transcriptomics were performed. Results indicated that the switch from an epithelial to a mesenchymal/migratory phenotype in HCC cells is characterized by reduced mitochondrial respiration, without signifcant diferences in glycolytic activity. Concomitantly, enhanced glutamine anaplerosis and biosynthetic use of TCA metabolites were proved through analysis of metabolite levels, as well as metabolic fuxes from U-13C6-Glucose and U-13C5-Glutamine. This correlated with increase in glutaminase 1 (GLS1) expression, whose inhibition reduced cell migration. Experiments where TGF-β function was activated with extracellular TGF-β1 or inhibited through TGF-β receptor I silencing showed that TGF-β induces a switch from oxidative metabolism, coincident with a decrease in OCR and the upregulation of glutamine transporter Solute Carrier Family 7 Member 5 (SLC7A5) and GLS1. TGF-β also regulated the expression of key genes involved in the fux of glycolytic intermediates and fatty acid metabolism. Together, these results indicate that autocrine activation of the TGF-β pathway regulates oxidative metabolism in HCC cells

Cd98hc (slc3A2) sustains amino acid and nucleotide availability for cell cycle progression

CD98 heavy chain (CD98hc) forms heteromeric amino acid (AA) transporters by interacting with different light chains. Cancer cells overexpress CD98hc-transporters in order to meet their increased nutritional and antioxidant demands, since they provide branched-chain AA (BCAA) and aromatic AA (AAA) availability while protecting cells from oxidative stress. Here we show that BCAA and AAA shortage phenocopies the inhibition of mTORC1 signalling, protein synthesis and cell proliferation caused by CD98hc ablation. Furthermore, our data indicate that CD98hc sustains glucose uptake and glycolysis, and, as a consequence, the pentose phosphate pathway (PPP). Thus, loss of CD98hc triggers a dramatic reduction in the nucleotide pool, which leads to replicative stress in these cells, as evidenced by the enhanced DNA Damage Response (DDR), S-phase delay and diminished rate of mitosis, all recovered by nucleoside supplementation. In addition, proper BCAA and AAA availability sustains the expression of the enzyme ribonucleotide reductase. In this regard, BCAA and AAA shortage results in decreased content of deoxynucleotides that triggers replicative stress, also recovered by nucleoside supplementation. On the basis of our findings, we conclude that CD98hc plays a central role in AA and glucose cellular nutrition, redox homeostasis and nucleotide availability, all key for cell proliferation

Dysfunctional LAT2 amino acid transporter is associated with cataract in mouse and humans

Cataract, the loss of ocular lens transparency, accounts for ∼50% of worldwide blindness and has been associated with water and solute transport dysfunction across lens cellular barriers. We show that neutral amino acid antiporter LAT2 (Slc7a8) and uniporter TAT1 (Slc16a10) are expressed on mouse ciliary epithelium and LAT2 also in lens epithelium. Correspondingly, deletion of LAT2 induced a dramatic decrease in lens essential amino acid levels that was modulated by TAT1 defect. Interestingly, the absence of LAT2 led to increased incidence of cataract in mice, in particular in older females, and a synergistic effect was observed with simultaneous lack of TAT1. Screening SLC7A8 in patients diagnosed with congenital or age-related cataract yielded one homozygous single nucleotide deletion segregating in a family with congenital cataract. Expressed in HeLa cells, this LAT2 mutation did not support amino acid uptake. Heterozygous LAT2 variants were also found in patients with cataract some of which showed a reduced transport function when expressed in HeLa cells. Whether heterozygous LAT2 variants may contribute to the pathology of cataract needs to be further investigated. Overall, our results suggest that defects of amino acid transporter LAT2 are implicated in cataract formation, a situation that may be aggravated by TAT1 defects

Tumors defective in homologous recombination rely on oxidative metabolism: relevance to treatments with PARP inhibitors

Mitochondrial metabolism and the generation of reactive oxygen species (ROS) contribute to the acquisition of DNA mutations and genomic instability in cancer. How genomic instability influences the metabolic capacity of cancer cells is nevertheless poorly understood. Here, we show that homologous recombination-defective (HRD) cancers rely on oxidative metabolism to supply NAD+ and ATP for poly(ADP-ribose) polymerase (PARP)-dependent DNA repair mechanisms. Studies in breast and ovarian cancer HRD models depict a metabolic shift that includes enhanced expression of the oxidative phosphorylation (OXPHOS) pathway and its key components and a decline in the glycolytic Warburg phenotype. Hence, HRD cells are more sensitive to metformin and NAD+ concentration changes. On the other hand, shifting from an OXPHOS to a highly glycolytic metabolism interferes with the sensitivity to PARP inhibitors (PARPi) in these HRD cells. This feature is associated with a weak response to PARP inhibition in patient-derived xenografts, emerging as a new mechanism to determine PARPi sensitivity. This study shows a mechanistic link between two major cancer hallmarks, which in turn suggests novel possibilities for specifically treating HRD cancers with OXPHOS inhibitors

Desarrollo de métodos de determinación e identificación de antibióticos y sus metabolitos en alimentos de origen animal por LC-MS y LC-MS/MS

[spa] Los antibióticos se usan en medicina veterinaria para curar enfermedades, para prevenirlas (uso profiláctico) y como promotores del crecimiento, aunque este último uso está prohibido en la Unión Europea desde 2006. La presencia de residuos de antibióticos en muestras alimentarias de origen animal supone un riesgo para la salud de los consumidores. Estos residuos pueden provocar problemas de alergias y toxicidad en individuos sensibles y generar resistencia bacteriana. Con el fin de proteger la seguridad alimentaria del consumidor, la UE estableció en la Regulación 2377/90/EC, unos límites máximos de residuos (MRL), es decir, concentraciones máximas de fármaco que pueden estar presentes en los alimentos de origen animal, para que sean seguros para el consumo humano. Durante esta tesis doctoral se han desarrollado y validado cuatro métodos multiresiduo para la determinación de quinolonas y β-lactamas (penicilinas y cefalosporinas) en leche de vaca siguiendo la normativa Europea 657/2002 y la guía de la FDA. Los métodos optimizados se basan en distintos tratamientos de muestra (extracción en fase sólida (SPE), microextracción líquido líquido dispersiva (DLLME) y extracción asistida por ultrasonidos seguida de una extracción en fase sólida dispersiva (USE-d-SPE)) y se analizaron por cromatografía de líquidos acoplada a la espectrometría de masas en tándem (LC-MS/MS). Con el fin de que la leche pueda ser apta para el consumo humano, es necesario que pase un determinado tiempo entre la última administración del antibiótico al animal y la recogida de la leche, con el fin de que pueda eliminarse del organismo los antibióticos y sus metabolitos. Si no se respeta este tiempo, la leche procedente de vacas medicadas con antibióticos puede contener residuos de éstos, además de compuestos resultantes de la metabolización en el animal. Por otro lado, también requiere que se eliminen los microorganismos patógenos a través de la aplicación de determinados tratamientos térmicos. Es de especial interés el estudio de la metabolización de los antibióticos y como pueden afectar los tratamientos térmicos sobre éstos, dando lugar a productos de transformación (TPs). Al igual que los antibióticos administrados, tanto los metabolitos como los TPs pueden provocar efectos adversos como toxicidad, alergias y en el caso de mantener la actividad antibacteriana, resistencia bacteriana. Así, en el segundo bloque de esta tesis, se ha estudiado la metabolización de diferentes antibióticos (ENR, CIP, DIF, SAR, AMOX, PENG, PIR y TIO), y la influencia de los tratamientos térmicos en la estructura de los antibióticos. Para conseguir este objetivo se han analizado diferentes muestras de leche fortificadas con quinolonas y β-lactamas, y también se han estudiado muestras de leche procedentes de animales medicados con enrofloxacina (ENR) y benzilpenicilina (PENG) y recogidas durante los tres días de tratamiento farmacológico y durante los cuatro días posteriores a la finalización de éste. Las muestras se analizaron mediante LC-ToF y LC-LTQ-Orbitrap. Se han determinado y caracterizado más de 60 TPs y metabolitos, siendo más de la mitad descritos por primera vez.[eng] The presence of antibiotic residues in food samples from animal origin is a risk to consumer health. These residues can cause allergies and toxicity problems in sensitive individuals and create bacterial resistance. In order to protect food consumer safety, the EU established in Regulation 2377/90/EC, a maximum residue levels (MRL). During this PhD thesis four multi-residue methods for the determination of quinolones and β-lactams (penicillins and cephalosporins) in cow's milk according to the European regulation 657/2002 and FDA guidance have been developed and validated. Optimized methods are based on various sample treatments (solid phase extraction (SPE), liquid dispersive liquid microextraction (DLLME) and ultrasound assisted extraction followed by a dispersive solid phase extraction (USE-d-SPE)) and analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS / MS). If a cow medicated is milked too soon, before all antibiotic and its metabolites are eliminated from the body, residues of the administered antibiotic and their metabolites can be found in the milk. These can pass to humans through the food chain causing health problems such as allergies, toxicity and resistant bacterial strains. On the other hand, milk is treated thermally (pasteurisation and sterilization) before human consumption to eliminate pathogens microorganisms. These processes can affect the residues of antibiotics and their metabolites modifying their structures and given several transformation products (TPs). Thus, in the second part of this thesis, we have studied the metabolism of different antibiotics (ENR, CIP, DIF, SAR, AMOX, PENG, PIR and TIO) and the influence of heat treatment on the structure of antibiotics. To achieve this goal different samples of milk fortified with quinolones and β-lactams have been analyzed. Samples of milk from animals medicated with enrofloxacin (ENR) and benzylpenicillin (PENG) and collected during the three-day of pharmacologic treatment and during the four days following the end of it have also studied. Samples were analyzed by LC-ToF and LC-LTQ-Orbitrap. They have been identified and 60 characterized TPs and metabolites, over half first described

Food safety in scavenger conservation: Diet-associated exposure to livestock pharmaceuticals and opportunist mycoses in threatened Cinereous and Egyptian vultures

Pharmaceuticals from veterinary treatments may enter terrestrial food webs when medicated livestock are available to wildlife in supplementary feeding stations aimed at the conservation of endangered scavengers. Here, we hypothesized that the exposure risk to livestock fluoroquinolones, as indicators of pharmaceutical burden in food, is related to the variable reliance of scavengers on domestic versus wild animal carcasses. Since the misuse of broad-spectrum antibiotics is a major predisposing factor for opportunistic mycoses, we evaluated disease signs potentially associated with diet-dependent drug exposure in nestlings of two threatened vultures. A greater occurrence (100%, n=14) and concentration of fluoroquinolones (mean±SD=73.0±27.5 µg L, range=33.2–132.7), mostly enrofloxacin, were found in Cinereous vultures, Aegypius monachus, due to their greater dependence on livestock carcasses than Egyptian vultures, Neophron percnopterus (fluoroquinolones occurrence: 44%, n=16, concentration: 37.9±16.6 µg L, range=11.5–55.9), which rely much more on carcasses of wild animals (42% of remains vs. 23% in the cinereous vulture). The chaotic, chronic and pulsed ingestion of these drugs throughout nestling development is proposed as one of the most plausible explanations for the high occurrence and intensity of oral Candida-like lesions in nestling vultures. The high occurrence of fluoroquinolone residues and disease hindered the probing of a cause-effect relationship between both factors in individual vultures. This relationship could be evaluated through a population-based approach by sampling vultures not exposed to these drugs. The high dependence of vultures on domestic animals today compared to past decades and the growing intensification of livestock farming, imply an expected increase in the impact of pharmaceuticals on scavenger populations. This requires further evaluation due to potential consequences in biodiversity conservation and environmental health. We encourage the prioritization of efforts to promote the use of less medicated free-ranging livestock carcasses left in the countryside, rather than stabled stocks made available in vulture restaurants. Additionally, attention should be paid to the population recovery of wild species that dominated scavenger diets in the past.Funds were provided by the projects CGL2009-12753-C02-01/BOS and CGL2010-15726 of Spanish Ministerio of Economía y CompetitividadPeer Reviewe