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Introduction Blood biomarkers represent a major advance for improving the management, diagnosis, and monitoring of Alzheimer's disease (AD). However, their context of use in relation to routine cerebrospinal fluid (CSF) analysis for the quantification of amyloid peptides and tau proteins remains to be determined. Methods We studied in two independent cohorts, the performance of blood biomarkers in detecting “nonpathological” (A−/T−/N−), amyloid (A+) or neurodegenerative (T+ /N+) CSF profiles. Results Plasma Aβ1–42/Aβ1–40 ratio and phosphorylated tau (p-tau(181)) were independent and complementary predictors of the different CSF profile and in particular of the nonpathological (A−/T−/N−) profile with a sensitivity and specificity close to 85%. These performances and the corresponding biomarker thresholds were significantly different from those related to AD detection. Conclusion The use of blood biomarkers to identify patients who may benefit from secondary CSF testing represents an attractive stratification strategy in the clinical management of patients visiting memory clinics. This could reduce the need for lumbar puncture and foreshadow the use of blood testing on larger populations.

Additional file 1: Table S1. Details about the diagnosis in the other neurodegenerative diseases (NDD) and other neurological disorders (OND) groups. Table S2. Correlations between plasma Biomarkers with Simoa and IPMS-Shim and Demographic Features. Table S3. Characteristics of Study Participants According to CSF Aβ42/40 Status and AT or AT(N) Profiles. Table S4. Correlations between Plasma Amyloid Biomarkers and CSF/Plasma Amyloid Biomarkers. Table S5. Baseline Characteristics of the 29 Individuals with follow-up and repeated biomarkers assessment. Fig. S1. Performance of the plasma amyloid biomarkers to discriminate A+T+ from A-T- subjects. ROC analysis of the amyloid biomarkers. AUC is presented with 95% confidence interval (CI).

SUMMARYThe Leigh syndrome is a severe inborn neurodegenerative encephalopathy commonly associated with pyruvate metabolism defects. The transcription factor E4F1, a key regulator of the pyruvate dehydrogenase (PDH) complex (PDC), was previously found to be mutated in Leigh syndrome patients, but the molecular mechanisms leading to cell death in E4F1-deficient neurons remain unknown. Here, we show that E4F1 directly regulatesDlatandElp3, two genes encoding key subunits of the PDC and of the Elongator complex, to coordinate AcetylCoenzyme A production and its utilization to acetylate tRNAs. Genetic inactivation ofE4f1in neurons during mouse embryonic development impaired tRNAs editing and induced an ATF4-mediated integrated stress response (ISR), leading to neuronal cell death and microcephaly. Furthermore, our analysis of PDH-deficient cells unraveled a crosstalk linking the PDC to ELP3 expression that is perturbed in Leigh syndrome patients. Altogether, our data support a model where pyruvate metabolism regulates the epitranscriptome to ensure protein translation fidelity.

International audience; The association between restless legs syndrome (RLS) and iron homeostasis remains unclear. We compared serum hepcidin and ferritin levels in patients with RLS and controls, and assessed their relationships with RLS phenotype, drug intake, and history of augmentation syndrome. 102 drug-free RLS patients (age 58.9 [24.5-77.2], 63 females) and 73 controls (age 56.8 [23.46-76.6], 45 females) underwent a polysomnography recording. Hepcidin levels were quantified by ELISA. 34 RLS patients had a second assessment after starting dopaminergic drugs. Ferritin level was low (

The use of dental stem cells has raised many hopes in the development of new treatments for neurodegenerative diseases. According to current statistics, about 1 in 6 people in the world would be affected by a neurological disease. This number continues to increase as the world's population ages, making neurodegenerative diseases probably the one of the major challenges of public health in the 21st century. Neurodegenerative diseases are characterized mainly by a progressive loss of cognitive abilities and patient autonomy related to loss and degeneration of neurons in brain structures. Unfortunately, today, the only treatments available for this type of disease do only relieve the symptoms, they do not treat them, and few clinical trials have been truly convincing to date. Hence, hope lies for these diseases in the development of other therapeutic approaches. As such, dental stem cells could be a promising area of research because of their rapid growth, their great capacity for differentiation into different types of cells (among neuronal ones for some of them) and how easy they can be obtained, without raising ethical issues as for example for embryonic stem cells., L’utilisation des cellules souches dentaires a fait naître de nombreux espoirs dans le développement de nouveaux traitements destinés aux maladies neurodégénératives. Si l’on se réfère aux statistiques actuelles, environ 1 personne sur 6 dans le monde serait atteinte par une maladie neurologique. Ce nombre ne cesse d’augmenter au fur et à mesure que la population mondiale vieillit, faisant des maladies neurodégénératives probablement l’un des principaux défis de la santé publique du XXIe siècle. Les maladies neurodégénératives se caractérisent principalement par une perte progressive des facultés cognitives et de l’autonomie des patients liée à une perte et une dégénérescence des neurones des structures cérébrales. Malheureusement, force est de constater que les seuls traitements disponibles actuellement pour ce type de pathologies ne font que soulager les symptômes et non les traiter et que peu d’essais cliniques à ce jour ont été véritablement probants. L’espoir réside donc pour ces maladies neurodégénératives dans le développement de nouvelles approches thérapeutiques. Les cellules souches dentaires pourraient constituer une nouvelle voie de recherche en thérapie cellulaire, de par leur croissance rapide, leur grande capacité de différenciation en différents types cellulaires (y compris en cellules neuronales pour certaines) et la facilité avec laquelle elles peuvent être obtenues sans soulever de problèmes d’éthique comme par exemple pour les cellules souches embryonnaires.

Background Amyloid pathology, which is one of the characteristics of Alzheimer’s disease (AD), results from altered metabolism of the beta-amyloid (Aβ) peptide in terms of synthesis, clearance, or aggregation. A decrease in cerebrospinal fluid (CSF) level Aβ1–42 is evident in AD, and the CSF ratio Aβ42/Aβ40 has recently been identified as one of the most reliable diagnostic biomarkers of amyloid pathology. Variations in inter-individual levels of Aβ1–40 in the CSF have been observed in the past, but their origins remain unclear. In addition, the variation of Aβ40 in the context of AD studied in several studies has yielded conflicting results. Methods Here, we analyzed the levels of Aβ1–40 using multicenter data obtained on 2466 samples from six different cohorts in which CSF was collected under standardized protocols, centrifugation, and storage conditions. Tau and p-tau (181) concentrations were measured using commercially available in vitro diagnostic immunoassays. Concentrations of CSF Aβ1–42 and Aβ1–40 were measured by ELISA, xMAP technology, chemiluminescence immunoassay (CLIA), and mass spectrometry. Statistical analyses were calculated for parametric and non-parametric comparisons, linear regression, correlation, and odds ratios. The statistical tests were adjusted for the effects of covariates (age, in particular). Results Regardless of the analysis method used and the cohorts, a slight but significant age-independent increase in the levels of Aβ40 in CSF was observed in AD. We also found a strong positive correlation between the levels of Aβ1–40 and p-tau (181) in CSF, particularly in control patients. Conclusions These results indicate that an increase in the baseline level of amyloid peptides, which are associated with an increase in p-tau (181), may be a biological characteristic and possibly a risk factor for AD. Further studies will be needed to establish a causal link between increased baseline levels of Aβ40 and the development of the disease.

International audience; : Background:Memory troubles and hippocampal atrophy are considered more frequent and focal atrophy less severe in late-onset (>65 years) than in presenile behavioral variant frontotemporal dementia (bvFTD). Objective:To compare cerebrospinal fluid (CSF) and plasma biomarkers in late-onset and presenile bvFTD. Methods:Multicentric retrospective study (2007-2017) on patients with clinical diagnosis of bvFTD. Results:This study included 44 patients (67%) with presenile and 22 (33%) with late-onset bvFTD (comparable mean disease duration; n = 11 with causal mutations). Hippocampal atrophy was more frequent (80% versus 25.8%) and severe in late-onset bvFTD (median Scheltens score: 3 [0–4] versus 1 [0–3]), without difference after adjustment for age. Lobar atrophy and focal hypometabolism/hypoperfusion were not different between groups. The median CSF Aβ1-42 and phosphorylated tau (P-tau) concentrations were in the normal range and comparable between groups. Axonal neurodegeneration biomarkers were within the normal range (CSF T-tau; plasma T-tau in late-onset bvFTD) or higher (plasma neurofilament light chain (NFL); plasma T-tau in presenile bvFTD) than the normal values, but globally not different between bvFTD groups. Plasma glial fibrillary acid protein (GFAP) was strongly increased in both bvFTD groups compared with the values in controls of the same age. Conclusion:The CSF and plasma biomarker profiles did not suggest a more aggressive neurodegeneration in the presenile group (comparable T-tau, NFL, and GFAP levels) or the co-existence of Alzheimer’s disease in the late-onset group (comparable and within normal range CSF Aβ1-42 and P-tau). The severity of the neurodegenerative process seems comparable in presenile and late-onset bvFTD.

Additional file 1 : SupTable 1. Number of patients/samples in each clinical group and Aβ40 detection method used.

Additional file 1: SupFigure 1. ROC curves of biomarker combinations. The ROC curves for the detection of the amyloid (+) patients in the WUSTL cohort (Panel A) or the AD patients in the Montpellier cohort (Panel B) for Aβ1–42, MS_pT181, MS_pT217, MS_pT181/ Aβ1–42 and MS_pT217/ Aβ1–42 were plotted. AUC values and statistical differences between curves of the panel A are reported in SupTable 3. SupFigure 2. CSF p-tau181 correlation with Pib-PET. The MS_pT181 values (panel A) and % of T181 phosphorylation (% MS_pT181, panel B) were plotted against their corresponding PiB-PET values in the WUSTL cohort composed of amyloid (−) and (+) patients. Correlation coefficients are indicated.

Additional file 4 : Sup-Figure 2. ROC curves of Aβ40, Aβ42 and Aβ42/40 ROC curves of Aβ40, Aβ42 and Aβ42/40 for the detection of AD in different cohorts. AUC of Aβ40 had lower values than the other biomarkers (Mtp-1 0.686 (0.638 to 0.731); Mtp-2 0.751 (0.711 to 0.788); Paris 0,679 (0.641 to 0.716); SPIN-Barcelona 0.730 (0.667 to 0,787)).

Additional file 5 : Sup-Figure 3. Aβ40 in different clinical groups. The Montpellier, Paris and SPIN-Barcelona cohorts displayed a large range of pathological samples from patients with Alzheimer’s disease (AD), cerebral amyloid angiopathy (CAA), frontotemporal degeneration (FTD), mild cognitive impairment (MCI), normal pressure hydrocephalus (NPH), vascular dementia (VASC), other neurological diseases (amytrophic lateral sclerosis, Parkinson’s disease, Lewy Body dementia..) (Other) and control (subjective cognitive impairment). Box plots with median and 25th/75th percentile of CSF Aβ40 values are plotted for the four cohorts (panels A-D). Note that the distribution of the diagnoses differ in the cohorts (see Methods). Non parametric Mann–Whitney U test were performed between the AD and the other clinical groups. P values below statistical significance are in red.

Background. Nowadays, invasive fungal infections (IFI) are of increasing importance and associated with an increased mortality. However, reliable diagnostic tools for the identification of patients suffering from an IFI are rare and associated with relevant weaknesses. Methods. Within this secondary analysis of an observational clinical study, an innovative biomarker panel (consisting of 62 biomarkers in total) was screened for the identification of septic shock patients suffering from an IFI. Fungal growth in blood cultures, intraoperative swabs, and Aspergillus spp. in deep respiratory tract specimens with accompanying pulmonary infiltrates were classified as infection, whereas Candida spp. in the respiratory tract or in fluids from drainages were classified as colonization. Plasma samples of 50 septic shock patients at six predefined timepoints within a period of 28 days following the onset of septic shock were available. Results. In total, 11 out of the 50 patients (22%) were shown to suffer from an IFI, whereas 22 patients (44%) presented with a fungal colonization. Within the presented biomarker panel, plasma levels of soluble intercellular adhesion molecule- (sICAM-) 1, thrombospondin-1, and vinculin were shown to be the most promising. sICAM-1 was shown to be increased in patients with an IFI, whereas thrombospondin-1 and vinculin revealed decreased plasma levels as compared to colonized patients as well as patients without any fungal findings at any time. Conclusion. Plasmatic measurements of sICAM-1, thrombospondin-1, and vinculin may help to facilitate the diagnosis of an IFI in human septic shock and to identify patients with an increased risk for an IFI. This trial is registered with DRKS00005463.

Additional file 3 : Sup-Figure 1. CSF Aβ42 and Aβ40 in Non-AD and AD populations with regards to ApoE status Mean-centered values of CSF Aβ42 (panels A-C) and Aβ40 (panels D-F) in total (all), NAD and AD population with regards to ApoE4 allele presence (+) or absence (-). Panels G-I illustrate the difference in Aβ40 between AD and NAD in the population with the ApoE status determine, in the total (all), ApoE4 allele presence (+) or absence (-).

Table S1. Patients’ clinical and biological characteristics. Table S2. Characteristics of brain metastases. Table S3. Univariate analysis of OS (A) in the whole MBC population (n = 244) and (B) in the BM population (n = 86): additional results. (DOCX 75 kb)

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Background and Aims: Laccase enzymes produced by Botrytis cinerea are involved in the oxidation of phenolic substances during the development of grey mould, which causes significant economic losses. The aim of this work was to study the structural and activity characteristics of the laccase enzymes secreted by three B. cinerea strains that are involved in the development of grey mould. Methods and Results: Laccase enzymes obtained from three B. cinerea strains [one reference strain (B05.10) and two strains obtained from two French vineyards (VA612 and RM344)] were characterised. Analysis by LC-QTOF-MS revealed that the three strains contained a mixture of Laccase-2-BcLCC2 and Laccase-3-BcLCC7. The structural characteristics of the laccases from the three strains, such as molecular weight and glycosylation degree, were identical. Nevertheless, their catalytic activities were significantly different. Conclusions: Differences in catalytic activities could be due either to possible differences in the relative amount of Laccase-2- BcLCC2 and Laccase-3-BcLCC7 produced by each strain or to differences in the glycosidic fraction of the enzymes. Significance of the Study: The severity of the infection caused by B. cinerea may be not only related to the infection level but also to the strain involved.

International audience; Human biological fluids are complex matrices containing many elements (ions, lipids, sugars, proteins, etc.). Proteins are essential for biomarker and disease discovery though the most abundant proteins often provide very limited clinically relevant data, as can be the case for albumin or immunoglobulins. In this work, we focused on depleting albumin from human serum samples using an albumin depletion and low abundance protein enrichment kit, which enabled the detection of several low-abundance proteins. By specific software prediction (Ingenuity), enriched proteins known as biomarkers for various diseases were identified. By employing an optimized supplier’s protocol, loss of proteins was decreased and could be revealed by LC-MS/MS protein identification. This depletion method proved to be faster and more cost-effective than antibody-based methods, and could be helpful for biomarker enrichment and detection in medical research.

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International audience; The European sea bass, Dicentrarchus labrax L., tolerates a range of salinities from freshwater to hyper-saline. To study differences in protein expression, fish were reared in both freshwater and seawater. After 3-month acclimation, gill and intestine epithelia were collected and the soluble protein extracted. In all, 362 spots were differentially expressed in the gills and intestines of fishes reared in seawater compared to those from freshwater. Fifty differential protein spots were excised from a colloidal Coomassie-stained gel. Nine separate protein spots were identified unambiguously by mass spectrometry and database searching. Among the six proteins over-expressed in gill cells in seawater, five were cytoskeleton proteins and one was the aromatase cytochrome P450. In gill cells under freshwater conditions, the two over-expressed proteins identified were the prolactin receptor and the major histocompatibility complex class II β-antigen. In intestinal cells under freshwater conditions, the Iroquois homeobox protein Ziro5 was upregulated over ninefold. The expression of these proteins, their possible direct or indirect roles in the adaptation of D. labrax to salinity, and their correspondences with a previous study are discussed.

Mammalian salivary glands are known to produce a number of biologically active peptides. The aim of this study was to extend our previous results showing the presence of a biologically active insulin-like immunoreactive peptide in rat salivary glands. In rodents, where two nonallelic and functional insulin genes are expressed, the co-expression of both genes seems to be limited to beta-cells of pancreatic islets or to embryologic developmental processes. We have investigated the expression of insulin genes in rat submandibular glands and in a murine immortalized submandibular cell line, SCA-9. For this purpose, total RNAs were isolated and submitted to reverse transcription. The cDNAs obtained were amplified by a nested polymerase chain reaction using rat preproinsulin I and II primers. Our data show that both preproinsulin I and II mRNAs are expressed in adult rat submandibular glands as well as in the SCA-9 cell line. The identification of salivary gland rat preproinsulin I and II was confirmed by direct sequencing. These results provide, for the first time, evidence for the expression of both preproinsulin I and II mRNA in an extra-pancreatic tissue from adult rodents.

Additional file 2: SupTable 1. Clinical and MRI characteristics of the Montpellier cohort. SupTable 2. Percentage of T181 and T217 phosphorylation. SupTable 3. AUC of phosphorylation of the different sites. SupTable 4. Correlation between CSF biomarkers and PiB-PET. SupTable 5. Internal quality control and reproducibility of the two methods.

Additional file 2: SupTable 1. Clinical and MRI characteristics of the Montpellier cohort. SupTable 2. Percentage of T181 and T217 phosphorylation. SupTable 3. AUC of phosphorylation of the different sites. SupTable 4. Correlation between CSF biomarkers and PiB-PET. SupTable 5. Internal quality control and reproducibility of the two methods.

In the rat mesangial cell (MC), activation of the bradykinin B2receptor (B2R) by bradykinin (BK) is associated with both phospholipase C (PLC) and A2(PLA2) activities and with inhibition of adenosine 3′,5′-cyclic monophosphate (cAMP) formation leading to cell contraction. Because cAMP plays an important role in the regulation of gene expression in general, we investigated the effect of increasing the intracellular cAMP concentration ([cAMP]i) in mesangial cells on the B2mRNA expression, on the density of B2receptor binding sites, on the BK-induced increase in both the free cytosolic Ca2+concentration ([Ca2+]i), and in the prostaglandin E2(PGE2) production. Forskolin, PGE2, and cAMP analog, 8-bromoadenosine 3′,5′-cyclic monophosphate (8-BrcAMP), were used to increase [cAMP]i. Twenty-four-hour treatment with forskolin, PGE2, and 8-BrcAMP resulted in significant increases in B2receptor binding sites, which were inhibited by cycloheximide. The maximum B2receptor mRNA expression (160% above control) was observed in cells treated during 24 h with forskolin and was prevented by actinomycin D. In contrast, thed- myo-inositol 1,4,5-trisphosphate (IP3) formation and the BK-induced increase in [Ca2+]i, reflecting activation of PLC, were not affected by increased levels of [cAMP]i. However, the BK-induced PGE2release, reflecting PLA2activity, was significantly enhanced. These data bring new information regarding the dual signaling pathways of B2receptors that can be differentially regulated by cAMP.

International audience; Salivary glands of various animal species have been reported to contain and suggested to produce glucagon or glucagon-like material, but the origin and the nature of this salivary peptide are still doubtful. The present study was undertaken to ascertain whether the glucagon gene is expressed in rat submandibular glands and in an immortalized murine cell line derived from salivary glands (SCA-9 cell line). For this purpose, total RNA was isolated from submandibular glands or cultured cells and submitted to reverse transcription. The cDNAs obtained were amplified by a nested polymerase chain reaction using preproglucagon primers. The results showed that the preproglucagon mRNA was expressed in adult rat submandibular glands but not in the SCA-9 cell line. Determination of cyclic DNA (cDNA) sequence established identity with the coding regions of rat pancreatic pre-proglucagon gene. In conclusion, these results strongly support the idea that rat submandibular glands could represent a source of extrapancreatic glucagon or of its precursor's peptide.