Background:Over 10 epidemiological studies have investigated air pollutants' association with thyroid hormone levels in pregnant women, but none have used personal air pollutant exposure data or included benzene, toluene, ethylbenzene, and xylene (BTEX). We assessed the relationship between personal exposure to nitrogen dioxide (NO2), particulate matter ≤2.5 µm (PM2.5), and BTEX with maternal thyroid hormones during pregnancy. Methods:The study relied on 437 pregnant women from the SEPAGES cohort (Grenoble, France, 2014-2017). Personal exposure to NO2, PM2.5, and BTEX was measured 1 week before blood sampling (mean: 19th gestational week), where thyroid hormones (free and total triiodothyronine (FT3, TT3), thyroxine (FT4, TT4), thyroid-stimulating hormone, and the TT3/TT4 ratio) were assessed. We linearly regressed air pollutants against individual thyroid hormone concentrations, adjusting for covariates, including urinary iodine concentration. Ambient NO2 and PM2.5 exposures were also analyzed for comparison. Results:Personal PM2.5 was positively associated with TT4 (β = 2.3%; 95% confidence interval [CI] = 0.4%, 4.2%, per doubling of exposure) and FT4 (β = 1.9%; 95% CI = -0.3%, 4.2%). On the contrary, negative associations between doubling the ethylbenzene exposure and TT4 (β = -1.2%; 95% CI = -2.4%, 0.1%) and FT4 levels (β = -1.3%; 95% CI = -2.7%, 0.1%) were observed. The association between ambient PM2.5 1 week before hormone measurement and FT4 was consistent with the association observed for personal exposure. Associations between ambient PM2.5 and TT4 were positive but attenuated across all examined time windows. Conclusions:Personal short-term exposure estimates provide evidence of a potential association between PM2.5, ethylbenzene, and altered thyroxine (TT4 and FT4) levels in pregnant women, warranting replication in other populations and larger samples.
The recent tightening of regulations on the polybrominated diphenyl ethers (PBDEs) production has led to an increase in the use of organophosphate flame retardants (OPFR). Although several toxicological studies suggest that these chemicals can disrupt thyroid homeostasis, epidemiological studies remain sparse. This work aims to investigate the associations between prenatal OPFR exposure and thyroid hormone levels in mothers and their newborns. The study population consisted of 442 mother-child pairs from the French SEPAGES cohort recruited between 2014 and 2017. Four OPFR metabolites -diphenyl phosphate (DPhP), di-n-butyl phosphate (DNBP), bis(1,3-dichloro-2-propyl) phosphate (BDCIPP), and bis(2-butoxyethyl) phosphate (BBOEP) -were measured in two pools of multiple urine samples collected during the second and third trimesters of pregnancy. Thyroid hormones were measured in maternal sera at the second trimester, and in newborns from a heel-prick blood spot. Adjusted linear regression models were used to assess the associations between each OPFR metabolite and each thyroid hormone. Maternal urinary iodine, child's sex, and exposure window were considered in additional analyses as potential effect modifiers. DNBP and BDCIPP were positively associated with newborn total thyroxine (TT4) and tended to be negatively associated with maternal total triiodothyronine (TT3). DPhP concentrations were also negatively associated with maternal thyroid stimulating hormone (TSH) levels. Our results suggest that exposure to OPFR could influence thyroid hormone levels in pregnant women and their newborns, raising concerns about potential adverse impacts on fetal development and postnatal health.
Phenylketonuria is an inherited metabolic disorder characterized by a deficiency in phenylalanine hydroxylase. However, the impact of this deficit on the patient’s overall metabolism is not fully known. Studying this pathology through untargeted metabolomics requires to determine a method for metabolites extraction, here applied to Dried Blood Spot (DBS), a matrix offering several practical advantages. The DBS of 30 phenylketonuric patients and 30 healthy controls were used for the study. Following a literature review, different extraction protocols and solvents were investigated, with or without an evaporation step, and compared to identify the most appropriate protocol to extract metabolites from the DBS for metabolomics analysis of phenylketonuria by LC-MS/MS, then applied to the patients and controls to validate its application to phenylketonuria. The most promising extraction method is a gentle agitation overnight at 4 °C, with an evaporation step, and an extraction solvent composed by 80
Here, we present the proof-of-concept of a lateral flow assay (LFA) that is capable of detecting small-molecule targets in a noncompetitive manner by deploying a sandwich-type format based on the aptamer kissing complex (AKC) strategy. A fluorescently labeled hairpin aptamer served as the signaling agent, while a specific RNA hairpin grafted onto the strip served as the capture element. The hairpin aptamer switched from an unfolded to a folded form in the presence of the target, resulting in kissing interactions between the loops of the reporter and the capture agents. This design triggered a target-dependent fluorescent signal at the test line. The AKC-based LFA was developed for the detection of adenosine, achieving a detection limit in the micromolar range. The assay revealed the presence of the same analyte in urine. The method also proved effective with another small molecule (theophylline). We believe that the AKC-based LFA approach could overcome many of the shortcomings associated with conventional signal-off methods and competitive processes.
Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) aptamer-based assays using metallic nanostructures or chelates as exogenous tags have gained growing attention in the last decade. We describe here a proof-of-concept study based on the exploitation of a simple organic molecule as a tag, i.e.l-thyroxine carrying four iodine atoms detectable by ICP-MS. A solid-phase assay involving the structure-switching format was deployed for the detection of the small molecule l-tyrosinamide as model target. The overall design involved (i) a reporter agent consisting of a DNA aptamer incorporating a single l-thyroxine label at its end and (ii) a capture agent, which is a partially complementary strand, immobilized on a microplate. Limit of detection in the nanomolar range was reported. The present labeling approach was further developed for the detection of a model protein (α-thrombin), using a sandwich mode, and proved effective in a biological matrix. We believe that the l-thyroxine tagging method could become a simple and robust alternative to commonly used labeling methods for ICP-MS aptamer-based assays.
Iron is an essential element to the well functionning of the organism and requires careful maintenance of its homeostasis. This is mainly due to hepcidin, a hormone secreted by the liver that controls the flow of iron within the body. It has a hyposideremic action by reducing the expression of ferroportin, the only protein known to this day, which can export iron into the extracellular environment. This has the effect of decreasing intestinal absorption and increasing intracellular retention, especially in macrophages. Hepcidin is stimulated by elevation of iron and inflammation while activation of erythropoiesis inhibits it. Understanding its regulation allows a better understanding of the pathophysiological mechanisms of overload diseases and iron deficiency. Therefore, hepcidin analysis is interesting for the exploration of iron homeostasis. In com-bination with other biological parameters of iron status, it is possible to find better instructions for therapeutic managements of iron metabolism diseases. Thus, an assaying method by coupling liquid chromatography and tandem mass spectrometry has been implemented at Grenoble University Hospital and the analytical performances of this assay met the laboratory requirements in terms of reliability of the analysis.
Herein, we report a novel approach for the design of a colorimetric aptasensor, relying on a Dye Salt Aggregation-based Colorimetric Oligonucleotide assay (DYSACO assay). This method is based on the use of an intercalating agent, Nile Blue (NB), whose aggregation capacities (and thus modification of its absorption spectrum) are drastically amplified by adding salts to the working solution. The presence of an aptamer could protect NB from such aggregation process due to its intercalation into double-stranded DNA and/or interaction with nucleobases. In response to the addition of the specific ligand, the competition between NB and the target for binding to the aptamer occurs, resulting in an increase in the dye salt aggregation and then in the blue-to-blank color change of the solution. The proof-of-principle was demonstrated by employing the anti-l-tyrosinamide aptamer and the assay was successfully applied to the trace enantiomer detection, allowing the detection of an enantiomeric impurity down to approximately 2% in a non-racemic sample. Through a reversed mechanism based on the increased capture of NB by DNA upon analyte binding, the sensing platform was further demonstrated for the Hg(II) detection. Water samples of different origin were spiked with Hg(II) analyte at final range concentrations comprised between (0.5-15 μM). An excellent overall recovery of 122 ± 14%; 105 ± 14%; 99 ± 9%; was respectively obtained from river, tap and mineral water, suggesting that the sensor can be used under real sample conditions. The assay was also shown to work for sensing the ochratoxin A and d-arginine vasopressin compounds, revealing its simplicity and generalizability potentialities.
Background: In vitro and toxicological studies have shown that non-persistent environmental chemicals can perturb thyroid hormone homeostasis. Epidemiological studies with improved exposure assessment (i.e., repeated urine samples) are needed to evaluate effects of these compounds, individually or as a mixture, in humans. We studied the associations between prenatal exposure to non-persistent environmental chemicals and neonatal thyroid hormones. Methods: The study population consisted of 442 mother-child pairs from the French SEPAGES mother-child cohort recruited between July 2014 and July 2017. For each participant, four parabens, five bisphenols, tri-closan, triclocarban, benzophenone-3 as well as metabolites of phthalates and of di(isononyl)cyclohexane-1,2-dicarboxylate were assessed in two pools of repeated urine samples (median: 21 spot urines per pool), collected in the 2nd and 3rd trimesters of pregnancy, respectively. Thyroid stimulating hormone (TSH) and total thyroxine (T4) levels were determined in newborns from a heel-prick blood spot. Maternal iodine and selenium were assessed in urine and serum, respectively. Adjusted linear regression (uni-pollutant model) and Bayesian Kernel Machine Regression (BKMR, mixture model) were applied to study overall and sex-stratified associations between chemicals and hormone concentrations.Results: Interaction with child sex was detected for several compounds. Triclosan, three parabens, and one phthalate metabolite (OH-MPHP) were negatively associated with T4 among girls in the uni-pollutant model. BKMR also suggested a negative association between the mixture and T4 in girls, whereas in boys the association was positive. The mixture was not linked to TSH levels, and for this hormone the uni-pollutant model revealed associations with only a few compounds.Conclusion: Our study, based on repeated urine samples to assess exposure, showed that prenatal exposure to some phenols and phthalates disturb thyroid hormone homeostasis at birth. Furthermore, both uni-pollutant and mixture models, suggested effect modification by child sex, while, to date underlying mechanisms for such sex -differences are not well understood.
Background: Studies characterizing associations between phenols, phthalates and thyroid hormones during pregnancy produce inconsistent results. This divergence may be partly attributable to false positives due to multiple comparison testing of large numbers of chemicals, and measurement error as studies rely on small numbers of biospecimens despite high intra-individual variability in urinary chemical metabolite concentrations. Objectives: This study employs a priori chemical filtering and expanded urinary biomonitoring to evaluate associations between phenol/phthalate exposures and serum thyroid hormones assessed during pregnancy. Methods: A two-tiered approach was implemented: a) In vitro high-throughput screening results from the ToxCast/Tox21 database, as informed by a thyroid Adverse Outcome Pathway network, were evaluated to select phenols/phthalates with activity on known and putative molecular initiating events in the thyroid pathway; and b) Adjusted linear regressions were used to study associations between filtered compounds and serum thyroid hormones measured in 437 pregnant women recruited in Grenoble area (France) between 2014 and 2017. Phenol/phthalate metabolites were measured in repeated spot urine sample pools (median: 21 samples/women). Results: The ToxCast/Tox21 screening reduced the chemical set from 16 to 13 and the associated number of statistical comparisons by 19%. Parabens were negatively associated with free triiodothyronine (T3) and the T3/T4 (total thyroxine) ratio. Monobenzyl phthalate was positively associated with total T4 and negatively with the T3/T4 ratio. Effect modification by iodine status was detected for several compounds (among them ΣDEHP and mono-n-butyl phthalate) that were associated with some hormones among women with normal iodine levels. Conclusion: For these chemicals, screening for compounds with an increased likelihood for thyroid-related effects and relying on repeated urine samples to assess exposures improved the overall performance of multichemical analyses of thyroid disruption. This approach may improve future evaluations of human data for the thyroid pathway with implication for fetal health and may serve as a model for evaluating other toxicity outcomes. https://doi.org/10.1289/EHP10239
Background COVID-19 severity is mainly related to lung impairment. However, preexisting patient characteristics and biomarkers at admission associated with this event are not precisely known.Methods We report 205 patients admitted for a proven COVID-19 in our institution between March 7 and April 22, 2020, particularly their comorbidities, respiratory severity, immune profile, and metabolic profile.Findings Median age was 70 years [interquartile range (IQR) 25-75: 60;79]; 115 (56·1%) patients were men. Oxygen supplementation of >2L/min was required in 107 patients (52·2%) after a median time of 8 days [IQR: 6;10] after the first symptoms; 67 (32·7%) patients were admitted to the intensive care unit (ICU), almost exclusively due to severe hypoxia. Patients requiring >2L/min oxygen therapy and/or ICU admission were older and more frequently males, with a significantly higher body mass index (BMI), a significantly higher total cholesterol (TC) / HDL cholesterol ratio, and higher triglycerides. They also had higher plasma levels of C-reactive protein (CRP) and interleukin 6 (IL-6); IL-6 >20 ng/L and CRP >70 mg/L were significantly associated with ICU admission and/or (for patients with a decision of limitation of life-support therapy) death. Higher BMI and TC/HDL-c ratio were associated with higher CRP and IL-6 levels. Steroid therapy was performed in 61 patients; while its clinical impact was inconclusive due to heterogeneous situations, IL-6 levels decreased significantly more in these patients.Interpretation Severe COVID-19 mostly relates to late-onset pneumonia associated with preexisting metabolic syndrome markers and a surge in inflammatory markers, allowing the early identification of at-risk patients.Funding This work was supported by Foundation University of Grenoble Alpes.### Competing Interest StatementThe authors have declared no competing interest.### Funding StatementThis work was supported by the Foundation University of Grenoble Alpes and Foundation Air Liquide.### Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:This study was conducted in accordance with the French legislation on the retrospective use of healthcare data, and ethical approval was given by the Clinical Research Direction of the Centre Hospitalier Universitaire Grenoble-Alpes. The BIOMARCOVID project is a research project that does not involve the human being and whose controller is the Centre Hospitalier Grenoble Alpes. This research has been registered in accordance with French regulations and meets the requirements of the National Commission for Information Technology and Civil Liberties (CNIL La Commission Nationale de l'Informatique et des Libertes) reference methodology 004.I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesAll data produced in the present study are available upon reasonable request to the authors
We describe herein an aptamer-based sensing approach that signal the presence of small-molecule targets when fluorescent DNA probes are challenged with the Ni2+ or Co2+ quencher metal ions. Functional oligonucleotides targeting L-tyrosinamide (L-Tym), adenosine (Ade) or cocaine (Coc) were end-labeled by the Texas-Red fluorophore. A fluorescence quenching occurred upon association of these transition metal ions with the free conjugates. The formation of the target-probe complex, by the way of variations in the overall binding of quencher metal ions along the DNA strands, led to a partial restoration (for the Ade and Coc systems) or a further attenuation (for the L-Tym system) of the fluorescence intensity. The absolute signal gain varied from 40 to 180% depending on the target-probe pair investigated. The approach was also used to detect the compound Ade in a spiked biological matrix in 1 min or less. The transition metal ion-based quenching strategy is characterized by its very simple implementation, low cost, and rapid signaling.
Glioblastoma (GBM) is the most aggressive malignant glioma, with a very poor prognosis; as such, efforts to explore new treatments and GBM's etiology are a priority. We previously described human GBM cells (R2J-GS) as exhibiting the properties of cancer stem cells (growing in serum-free medium and proliferating into nude mice when orthotopically grafted). Sodium selenite (SS)-an in vitro attractive agent for cancer therapy against GBM-was evaluated in R2J-GS cells. To go further, we launched a preclinical study: SS was given orally, in an escalation-dose study (2.25 to 10.125 mg/kg/day, 5 days on, 2 days off, and 5 days on), to evaluate (1) the absorption of selenium in plasma and organs (brain, kidney, liver, and lung) and (2) the SS toxicity. A 6.75 mg/kg SS dose was chosen to perform a tumor regression assay, followed by MRI, in R2J-GS cells orthotopically implanted in nude mice, as this dose was nontoxic and increased brain selenium concentration. A group receiving TMZ (5 mg/kg) was led in parallel. Although not reaching statistical significance, the group of mice treated with SS showed a slower tumor growth vs. the control group (p = 0.08). No difference was observed between the TMZ and control groups. We provide new insights of the mechanisms of SS and its possible use in chemotherapy.
We introduced an aptamer switch design that relies on the ability of post-transition/transition metal ions to trigger, through their coordination to nucleobases, substantial DNA destabilization. In the absence of molecular target, the addition of one such metal ion to usual aptamer working solutions promotes the formation of an alternative, inert DNA state. Upon exposure to the cognate compound, the equilibrium is shifted towards the competent DNA form. The switching process was preferentially activated by metal ions of intermediate base over phosphate complexation preference (i.e. Pb2+ , Cd2+ ) and operated with diversely structured DNA molecules. This very simple aptamer switch scheme was applied to the detection of small organics using the fluorescence anisotropy readout mode. We envision that the approach could be adapted to a variety of signalling methods that report on changes in the surface charge density of DNA receptors.
Many similarities between tryptophan (Trp) and phenylalanine (Phe) metabolisms exist. It is possible that a modification of Trp metabolism might be seen in phenylketonuria (PKU). As some of these metabolites have neuroactive properties, they should be consider in neurological impairment seen in this pathology and not totally explained by blood Phe concentrations. One hundred and fifty-one adult PKU patients (mean age 26.8 years) were included for this study. Plasma Trp, kynurenine (KYN), 3-hydroxykynurenic acid (3HK), and kynurenic acid (KA) were analyzed by liquid chromatography coupled with tandem mass spectrometry. KYN and 3HK were significantly lower in PKU patients compared to general population (P < .0001), and KA was significantly enhanced is this population (P= .009). Furthermore, 3HK concentration was significantly different between PKU patients underwent controlled low-Phe diet compared to PKU patients without this diet (P= .0016). In PKU patients with diet, taking AA substitute enable higher plasma 3HK concentration than without (P= .0008) but still not reaching general population level (P < .0001). Although further study has to be done, it is clear that Trp metabolism is modified in adult PKU patients. An exploration of complete Trp metabolism, and not only Trp concentration, is needed in PKU population, but also in other inborn error of metabolism treated with hypoprotidic diet.
Giant cell arteritis (GCA) is the most frequent systemic vasculitis occurring in adults older than 50 years, and aortitis is described in 40% to 80% of patients. The treatment relies on corticosteroids, but it is complicated by high rates of relapses and adverse effects and may be unable to completely inhibit aortic inflammation. Moreover, most of the current data regarding the pathophysiology of GCA have been obtained from bioassays using blood and temporal arteries, as well as histological analyses of temporal arteries and very few aortic aneurysms from patients with GCA. The limitations of these analyses prevent researchers from determining the implications of specific targets and studying the effects of targeted treatments. Several experimental models have been developed, but to date, a perfect model is not available for GCA, particularly for studies of large-vessel vasculitis. The review focuses on the perspectives on experimental models and new therapeutic targets in giant cell arteritis.
Adult patients with de novo acute myeloid leukemia show a functional deregulation of redox balance at diagnosis which is correlated with molecular subtypes and overall survival
Abstract The aim of this study was to assess the validity of the predictive INTERSALT equation using spot urine samples to estimate 24-h urinary Na (24-hUNa) excretion and daily Na intake among the French adult population. Among 193 French adults (‘validation sample’), we assessed the validity by comparing predicted 24-hUNa excretion from spot urine and measured 24-hUNa excretion from 24-h urine collections. Spearman correlation coefficients and Bland–Altman plots were used and we calculated calibration coefficients. In a nationally representative sample of 1720 French adults (‘application sample’), the calibrated predictive equation was then applied to the spot urine Na values to estimate 24-hUNa excretion and daily Na intake. In that sample, predicted Na intake was compared with that estimated from 24-h dietary recalls. Results were adjusted and corrected using calibration coefficients. In the validation sample, the measured 24-hUNa excretion was on average 14 % higher than the predicted 24-hUNa (+13 % for men and +16 % for women). Correlation between measured and predicted 24-hUNa excretion was moderate (Spearman r 0·42), and the Bland–Altman plots showed underestimation at lower excretion level and overestimation at higher level. In the application study, estimated daily salt intake was 8·0 g/d using dietary recalls, 8·1 g/d using predicted INTERSALT equation and 9·3 g/d after applying calibration coefficients calculated in the validation study. Despite overall underestimation of 24-hUNa excretion by spot urinary Na, the use of predictive INTERSALT equation remains an acceptable alternative in monitoring global Na intake/excreted in the French population but its use is not advised at the individual level.