Structure Fédérative de Recherche Bonamy

Exosomes are nanometer-sized microvesicles formed in multivesicular bodies (MVBs) during endosome maturation. Exosomes are released from cells into the microenvironment following fusion of MVBs with the plasma membrane. During the last decade, skeletal muscle-secreted proteins have been identified with important roles in intercellular communications. To investigate whether muscle-derived exosomes participate in this molecular dialog, we determined and compared the protein contents of the exosome-like vesicles (ELVs) released from C2C12 murine myoblasts during proliferation (ELV-MB), and after differentiation into myotubes (ELV-MT). Using a proteomic approach combined with electron microscopy, western-blot and bioinformatic analyses, we compared the protein repertoires within ELV-MB and ELV-MT. We found that these vesicles displayed the classical properties of exosomes isolated from other cell types containing components of the ESCRT machinery of the MVBs, as well as numerous tetraspanins. Specific muscle proteins were also identified confirming that ELV composition also reflects their muscle origin. Furthermore quantitative analysis revealed stage-preferred expression of 31 and 78 proteins in ELV-MB and ELV-MT respectively. We found that myotube-secreted ELVs, but not ELV-MB, reduced myoblast proliferation and induced differentiation, through, respectively, the down-regulation of Cyclin D1 and the up-regulation of myogenin. We also present evidence that proteins from ELV-MT can be incorporated into myoblasts by using the GFP protein as cargo within ELV-MT. Taken together, our data provide a useful database of proteins from C2C12-released ELVs throughout myogenesis and reveals the importance of exosome-like vesicles in skeletal muscle biology.

RATIONALE: The hallmark of severe influenza virus infection is excessive inflammation of the lungs. Platelets are activated during influenza, but their role in influenza virus pathogenesis and inflammatory responses is unknown. OBJECTIVES: To determine the role of platelets during influenza A virus infections and propose new therapeutics against influenza. METHODS: We used targeted gene deletion approaches and pharmacologic interventions to investigate the role of platelets during influenza virus infection in mice. MEASUREMENTS AND MAIN RESULTS: Lungs of infected mice were massively infiltrated by aggregates of activated platelets. Platelet activation promoted influenza A virus pathogenesis. Activating protease-activated receptor 4, a platelet receptor for thrombin that is crucial for platelet activation, exacerbated influenza-induced acute lung injury and death. In contrast, deficiency in the major platelet receptor glycoprotein IIIa protected mice from death caused by influenza viruses, and treating the mice with a specific glycoprotein IIb/IIIa antagonist, eptifibatide, had the same effect. Interestingly, mice treated with other antiplatelet compounds (antagonists of protease-activated receptor 4, MRS 2179, and clopidogrel) were also protected from severe lung injury and lethal infections induced by several influenza strains. CONCLUSIONS: The intricate relationship between hemostasis and inflammation has major consequences in influenza virus pathogenesis, and antiplatelet drugs might be explored to develop new antiinflammatory treatment against influenza virus infections.

Background Clinical benefit from programmed cell death 1 receptor (PD-1) inhibitors relies on reinvigoration of endogenous antitumor immunity. Nonetheless, robust immunological markers, based on circulating immune cell subsets associated with therapeutic efficacy are yet to be validated. Methods We isolated peripheral blood mononuclear cell from three independent cohorts of melanoma and Merkel cell carcinoma patients treated with PD-1 inhibitor, at baseline and longitudinally after therapy. Using multiparameter flow cytometry and cell sorting, we isolated four subsets of CD8 + T cells, based on PD-1 and TIGIT expression profiles. We performed phenotypic characterization, T cell receptor sequencing, targeted transcriptomic analysis and antitumor reactivity assays to thoroughly characterize each of these subsets. Results We documented that the frequency of circulating PD-1 + TIGIT + (DPOS) CD8 + T-cells after 1 month of anti-PD-1 therapy was associated with clinical response and overall survival. This DPOS T-cell population was enriched in highly activated T-cells, tumor-specific and emerging T-cell clonotypes and T lymphocytes overexpressing CXCR5, a key marker of the CD8 cytotoxic follicular T cell population. Additionally, transcriptomic profiling defined a specific gene signature for this population as well as the overexpression of specific pathways associated with the therapeutic response. Conclusions Our results provide a convincing rationale for monitoring this PD-1 + TIGIT + circulating population as an early cellular-based marker of therapeutic response to anti-PD-1 therapy.

Mycolactone, a lipid-like toxin, is the major virulence factor of Mycobacterium ulcerans, the etiological agent of Buruli ulcer. Its involvement in lesion development has been widely described in early stages of the disease, through its cytotoxic and immunosuppressive activities, but less is known about later stages. Here, we revisit the role of mycolactone in disease outcome and provide the first demonstration of the pro-inflammatory potential of this toxin. We found that the mycolactone-containing mycobacterial extracellular vesicles produced by M. ulcerans induced the production of IL-1β, a potent pro-inflammatory cytokine, in a TLR2-dependent manner, targeting NLRP3/1 inflammasomes. We show our data to be relevant in a physiological context. The in vivo injection of these mycolactone-containing vesicles induced a strong local inflammatory response and tissue damage, which were prevented by corticosteroids. Finally, several soluble pro-inflammatory factors, including IL-1β, were detected in infected tissues from mice and Buruli ulcer patients. Our results revisit Buruli ulcer pathophysiology by providing new insight, thus paving the way for the development of new therapeutic strategies taking the pro-inflammatory potential of mycolactone into account.

A major limitation of the 2D culture systems is that they fail to recapitulate the in vivo 3D cellular microenvironment whereby cell-cell and cell-extracellular matrix (ECM) interactions occur. In this paper, a biomaterial scaffold that mimics the structure of collagen fibers was produced by jet-spraying. This micro-fiber polycaprolactone (PCL) scaffold was evaluated for 3D culture of human bone marrow mesenchymal stromal cells (MSCs) in comparison with a commercially available electrospun scaffold. The jet-sprayed scaffolds had larger pore diameters, greater porosity, smaller diameter fibers, and more heterogeneous fiber diameter size distribution compared to the electrospun scaffolds. Cells on jet-sprayed constructs exhibited spread morphology with abundant cytoskeleton staining, whereas MSCs on electrospun scaffolds appeared less extended with fewer actin filaments. MSC proliferation and cell infiltration occurred at a faster rate on jet-sprayed compared to electrospun scaffolds. Osteogenic differentiation of MSCs and ECM production as measured by ALP, collagen and calcium deposition was superior on jet-sprayed compared to electrospun scaffolds. The jet-sprayed scaffold which mimics the native ECM and permits homogeneous cell infiltration is important for 3D in vitro applications such as bone cellular interaction studies or drug testing, as well as bone tissue engineering strategies.

The development of biologically and mechanically competent hydrogels is a prerequisite in cartilage engineering. We recently demonstrated that a marine exopolysaccharide, GY785, stimulates the in vitro chondrogenesis of adipose stromal cells. In the present study, we thus hypothesized that enriching our silated hydroxypropyl methylcellulose hydrogel (Si-HPMC) with GY785 might offer new prospects in the development of scaffolds for cartilage regeneration. The interaction properties of GY785 with growth factors was tested by surface plasmon resonance (SPR). The biocompatibility of Si-HPMC/GY785 towards rabbit articular chondrocytes (RACs) and its ability to maintain and recover a chondrocytic phenotype were then evaluated in vitro by MTS assay, cell counting and qRT-PCR. Finally, we evaluated the potential of Si-HPMC/GY785 associated with RACs to form cartilaginous tissue in vivo by transplantation into the subcutis of nude mice for 3 weeks. Our SPR data indicated that GY785 was able to physically interact with BMP-2 and TGFβ. Our analyses also showed that three-dimensionally (3D)-cultured RACs into Si-HPMC/GY785 strongly expressed type II collagen (COL2) and aggrecan transcripts when compared to Si-HPMC alone. In addition, RACs also produced large amounts of extracellular matrix (ECM) containing glycosaminoglycans (GAG) and COL2. When dedifferentiated RACs were replaced in 3D in Si-HPMC/GY785, the expressions of COL2 and aggrecan transcripts were recovered and that of type I collagen decreased. Immunohistological analyses of Si-HPMC/GY785 constructs transplanted into nude mice revealed the production of a cartilage-like extracellular matrix (ECM) containing high amounts of GAG and COL2. These results indicate that GY785-enriched Si-HPMC appears to be a promising hydrogel for cartilage tissue engineering. Copyright © 2015 John Wiley & Sons, Ltd.

BACKGROUND: The pathogenesis of influenza A virus (IAV) infections is a multifactorial process that includes the replication capacity of the virus and a harmful inflammatory response to infection. Formyl peptide receptor 2 (FPR2) emerges as a central receptor in inflammatory processes controlling resolution of acute inflammation. Its role in virus pathogenesis has not been investigated yet. METHODS: We used pharmacologic approaches to investigate the role of FPR2 during IAV infection in vitro and in vivo. RESULTS: In vitro, FPR2 expressed on A549 cells was activated by IAV, which harbors its ligand, annexin A1, in its envelope. FPR2 activation by IAV promoted viral replication through an extracellular-regulated kinase (ERK)-dependent pathway. In vivo, activating FPR2 by administering the agonist WKYMVm-NH2 decreased survival and increased viral replication and inflammation after IAV infection. This effect was abolished by treating the mice with U0126, a specific ERK pathway inhibitor, showing that, in vivo, the deleterious role of FPR2 also occurs through an ERK-dependent pathway. In contrast, administration of the FPR2 antagonist WRW4 protected mice from lethal IAV infections. CONCLUSIONS: These data show that viral replication and IAV pathogenesis depend on FPR2 signaling and suggest that FPR2 may be a promising novel strategy to treat influenza.

// Carole Achard 1,2,3 , Nicolas Boisgerault 1,2,3 , Tiphaine Delaunay 1,2,3 , David Roulois 1,2,3 , Steven Nedellec 3,4 , Pierre-Joseph Royer 3,5 , Mallory Pain 3,5 , Chantal Combredet 6 , Mariana Mesel-Lemoine 6 , Laurent Cellerin 7 , Antoine Magnan 3,5,8 , Frédéric Tangy 6 , Marc Grégoire 1,2,3 and Jean-François Fonteneau 1,2,3 1 INSERM, UMR892, Institut de Recherche en Santé de l’Université de Nantes, Nantes, France 2 CNRS, UMR6299, Institut de Recherche en Santé de l’Université de Nantes, Nantes, France 3 Université de Nantes, Nantes, France 4 INSERM UMS016, SFR Santé, Nantes, France 5 INSERM UMRS1087, Institut du Thorax, Nantes, France 6 CNRS UMR3569, Unité de Génomique Virale et Vaccination, Institut Pasteur, Paris, France 7 CHU de Nantes, Service d’Oncologie Médicale Thoracique et Digestive, Nantes, France 8 CHU de Nantes, Service de Pneumologie, Nantes, France Correspondence to: Jean-François Fonteneau, email: // Keywords : oncolytic virus, measles virus, oncolytic virotherapy, mesothelioma, type I interferon Received : October 08, 2015 Accepted : October 22, 2015 Published : November 02, 2015 Abstract Attenuated measles virus (MV) is currently being evaluated as an oncolytic virus in clinical trials and could represent a new therapeutic approach for malignant pleural mesothelioma (MPM). Herein, we screened the sensitivity to MV infection and replication of twenty-two human MPM cell lines and some healthy primary cells. We show that MV replicates in fifteen of the twenty-two MPM cell lines. Despite overexpression of CD46 by a majority of MPM cell lines compared to healthy cells, we found that the sensitivity to MV replication did not correlate with this overexpression. We then evaluated the antiviral type I interferon (IFN) responses of MPM cell lines and healthy cells. We found that healthy cells and the seven insensitive MPM cell lines developed a type I IFN response in presence of the virus, thereby inhibiting replication. In contrast, eleven of the fifteen sensitive MPM cell lines were unable to develop a complete type I IFN response in presence of MV. Finally, we show that addition of type I IFN onto MV sensitive tumor cell lines inhibits replication. These results demonstrate that defects in type I IFN response are frequent in MPM and that MV takes advantage of these defects to exert oncolytic activity.

We previously reported that subretinal injection of AAV2/5 RK.cpde6β allowed long-term preservation of photoreceptor function and vision in the rod-cone dysplasia type 1 (rcd1) dog, a large animal model of naturally occurring PDE6β deficiency. The present study builds on these earlier findings to provide a detailed assessment of the long-term effects of gene therapy on the spatiotemporal pattern of retinal degeneration in rcd1 dogs treated at 20 days of age. We analyzed the density distribution of the retinal layers and of particular photoreceptor cells in 3.5-year-old treated and untreated rcd1 dogs. Whereas no rods were observed outside the bleb or in untreated eyes, gene transfer halted rod degeneration in all vector-exposed regions. Moreover, while gene therapy resulted in the preservation of cones, glial cells and both the inner nuclear and ganglion cell layers, no cells remained in vector-unexposed retinas, except in the visual streak. Finally, the retinal structure of treated 3.5-year-old rcd1 dogs was identical to that of unaffected 4-month-old rcd1 dogs, indicating near complete preservation. Our findings indicate that gene therapy arrests the degenerative process even if intervention is initiated after the onset of photoreceptor degeneration, and point to significant potential of this therapeutic approach in future clinical trials. We previously reported that subretinal injection of AAV2/5 RK.cpde6β allowed long-term preservation of photoreceptor function and vision in the rod-cone dysplasia type 1 (rcd1) dog, a large animal model of naturally occurring PDE6β deficiency. The present study builds on these earlier findings to provide a detailed assessment of the long-term effects of gene therapy on the spatiotemporal pattern of retinal degeneration in rcd1 dogs treated at 20 days of age. We analyzed the density distribution of the retinal layers and of particular photoreceptor cells in 3.5-year-old treated and untreated rcd1 dogs. Whereas no rods were observed outside the bleb or in untreated eyes, gene transfer halted rod degeneration in all vector-exposed regions. Moreover, while gene therapy resulted in the preservation of cones, glial cells and both the inner nuclear and ganglion cell layers, no cells remained in vector-unexposed retinas, except in the visual streak. Finally, the retinal structure of treated 3.5-year-old rcd1 dogs was identical to that of unaffected 4-month-old rcd1 dogs, indicating near complete preservation. Our findings indicate that gene therapy arrests the degenerative process even if intervention is initiated after the onset of photoreceptor degeneration, and point to significant potential of this therapeutic approach in future clinical trials.

The use of small interfering RNA (siRNA) to regulate oncogenes appears as a promising strategy in the context of cancer therapy, especially if they are vectorized by a smart delivery system. In this study, we investigated the cellular trafficking of a siRNA nanovector (called CS-MSN) functionalized with the cell-penetrating peptide gH625 in a triple-negative breast cancer model. With complementary techniques, we showed that siRNA nanovectors were internalized by both clathrin- and caveolae-mediated endocytosis. The presence of gH625 at the surface of the siRNA nanovector did not modify the entry pathway of CS-MSN, but it increased the amount of siRNA found inside the cells. Results suggested an escape of siRNA from endosomes, which is enhanced by the presence of the peptide gH625, whereas nanoparticles continued their trafficking into lysosomes. The efficiency of CS-MSN to inhibit the GFP in MDA-MB-231 cells was 1.7-fold higher than that of the nanovectors without gH625.

BACKGROUND: The identification of circulating biomarkers associated with the risk of type 2 diabetes (T2D) is useful for improving the current prevention strategies in the most at-risk patients. Here, we aimed to investigate the association of plasma apolipoprotein concentrations in prediabetes subjects with the incidence of new-onset T2D during follow-up. METHODS: In the IT-DIAB prospective study, 307 participants with impaired fasting glucose levels (fasting plasma glucose [FPG]: 110-125 mg/dL) were followed yearly for 5 years. The onset of T2D was defined as a first FPG value ≥ 126 mg/dL during follow-up. Apolipoprotein (apo)A-I, A-II, A-IV, B100, C-I, C-II, C-III, C-IV, D, E, F, H, J, L1, M, and (a) plasma concentrations were determined by mass spectrometry. Correlations between apolipoproteins and metabolic parameters at baseline were assessed by Spearman's coefficients. Kaplan-Meier curves were drawn using a ternary approach based on terciles and incident T2D. The association between plasma apolipoproteins concentrations and the incidence of T2D was determined using Cox proportional-hazards models. RESULTS: , and statin use, the plasma levels of apoC-I, apoC-II, apoC-III, apoE, apoF, apoH, apoJ, and apoL1 were positively associated with a high risk for T2D. After further adjustment for plasma triglycerides, only apoE (1 SD natural-log-transformed hazard ratio: 1.28 [95% confidence interval: 1.06; 1.54]; p = 0.010), apoF (1.22 [1.01; 1.48]; p = 0.037), apoJ (1.24 [1.03; 1.49]; p = 0.024), and apoL1 (1.26 [1.05; 1.52]; p = 0.014) remained significantly associated with the onset of T2D. Kaplan-Meier survival curves also showed that the lower third of plasma apoE levels (< 5.97 mg/dL) was significantly associated with a lower risk of conversion to T2D (log-rank test, p = 0.002) compared to the middle and upper thirds. CONCLUSIONS: The plasma apoE levels are positively associated with the risk of T2D in prediabetes subjects, independently of traditional risk factors. The possible associations of apoF, apoJ, and apoL1 with T2D risk also pave the way for further investigations. Trial registration This trial was registered at clinicaltrials.gov as NCT01218061 and NCT01432509.

Inhibiting the growth of tumor vasculature represents one of the relevant strategies against tumor progression. Between all the different pro-angiogenic molecular targets, plasma membrane glycosphingolipids have been under-investigated. In this present study, we explore the anti-angiogenic therapeutic advantage of a tumor immunotherapy targeting the globotriaosylceramide Gb3. In this purpose, a monoclonal antibody against Gb3, named 3E2 was developed and characterized. We first demonstrate that Gb3 is over-expressed in proliferative endothelial cells relative to quiescent cells. Then, we demonstrate that 3E2 inhibits endothelial cell proliferation in vitro by slowing endothelial cell proliferation and by increasing mitosis duration. Antibody 3E2 is further effective in inhibiting ex vivo angiogenesis in aorta ring assays. Moreover, 3E2 treatment inhibits NXS2 neuroblastoma development and liver metastases spreading in A/J mice. Immunohistology examination of the NXS2 metastases shows that only endothelial cells, but not cancer cells express Gb3. Finally, 3E2 treatment diminishes tumor vessels density, proving a specific therapeutic action of our monoclonal antibody to tumor vasculature. Our study demonstrates that Gb3 is a viable alternative target for immunotherapy and angiogenesis inhibition.

In multiple sclerosis (MS), alterations of the gut microbiota lead to inflammation. However, the role of other microbiomes in the body in MS has not been fully elucidated. In a pilot case-controlled study, we carried out simultaneous characterization of faecal and oral microbiota and conducted an in-depth analysis of bacterial alterations associated with MS. Using 16S rRNA sequencing and metabolic inference tools, we compared the oral/faecal microbiota and bacterial metabolism pathways in French MS patients (n = 14) and healthy volunteers (HV, n = 21). A classification model based on metabolite flux balance was established and validated in an independent German cohort (MS n = 12, HV n = 38). Our analysis revealed decreases in diversity indices and oral/faecal compartmentalization, the depletion of commensal bacteria (Aggregatibacter and Streptococcus in saliva and Coprobacter and Roseburia in faeces) and enrichment of inflammation-associated bacteria in MS patients (Leptotrichia and Fusobacterium in saliva and Enterobacteriaceae and Actinomyces in faeces). Several microbial pathways were also altered (the polyamine pathway and remodelling of bacterial surface antigens and energetic metabolism) while flux balance analysis revealed associated alterations in metabolite production in MS (nitrogen and nucleoside). Based on this analysis, we identified a specific oral metabolite signature in MS patients, that could discriminate MS patients from HV and rheumatoid arthritis patients. This signature allowed us to create and validate a discrimination model on an independent cohort, which reached a specificity of 92%. Overall, the oral and faecal microbiomes were altered in MS patients. This pilot study highlights the need to study the oral microbiota and oral health implications in patients with autoimmune diseases on a larger scale and suggests that knowledge of the salivary microbiome could help guide the identification of new pathogenic mechanisms associated with the microbiota in MS patients.

Melanoma is the most aggressive skin cancer with an extremely challenging therapy. The dermal-epidermal junction (DEJ) degradation and subsequent dermal invasion are the earliest steps of melanoma dissemination, but the mechanisms remain elusive. We previously identified Tspan8 as a key actor in melanoma invasiveness. Here, we investigated Tspan8 mechanisms of action during dermal invasion, using a validated skin-reconstruct-model that recapitulates melanoma dermal penetration through an authentic DEJ. We demonstrate that Tspan8 is sufficient to induce melanoma cells’ translocation to the dermis. Mechanistically, Tspan8+ melanoma cells cooperate with surrounding keratinocytes within the epidermis to promote keratinocyte-originated proMMP-9 activation process, collagen IV degradation and dermal colonization. This concurs with elevated active MMP-3 and low TIMP-1 levels, known to promote MMP-9 activity. Finally, a specific Tspan8-antibody reduces proMMP-9 activation and dermal invasion. Overall, our results provide new insights into the role of keratinocytes in melanoma dermal colonization through a cooperative mechanism never reported before, and establish for the first time the pro-invasive role of a tetraspanin family member in a cell non-autonomous manner. This work also displays solid arguments for the use of Tspan8-blocking antibodies to impede early melanoma spreading and therefore metastasis.

Activation of cell signaling by reactive chemicals and pollutants is an important issue for human health. It has been shown that lipophilic nitro-benzoxadiazole (NBD) compounds rapidly move across the plasma membrane and enhance Epidermal Growth Factor Receptor (EGFR) tyrosine phosphorylation in cancer cells. Unlike ligand-dependent activation, the mechanism of this induction relies on the generation of hydrogen peroxide, which is involved in the activation of the catalytic site of the receptor and the inactivation of protein tyrosine phosphatase PTP-1B. Production of H2O2 during redox transformation of NBD compounds is associated with the transition of a monomeric form of Cu/Zn superoxide dismutase 1 (SOD1) to stable dimers. The highly stable and functionally active SOD1 dimer, in the absence of adequate activities in downstream reactions, promotes the disproportionate production and accumulation of intracellular hydrogen peroxide shortly after exposure to NBD compounds. The intrinsic fluorescence of small compounds was used to demonstrate their binding to SOD1. Our data indicate that H2O2 and concomitantly generated electrophilic intermediates behave as independent entities, but all contribute to the biological reactivity of NBD compounds. This study opens a promising path to identify new biomarkers of oxidative/electrophilic stress in the progression of cancer and other diseases.

Polyethylene micro-sized wear particles released from orthopedic implants promote inflammation and osteolysis; however, less is known about the bioactivity of polyethylene nanosized wear particles released from the last generation of polymer-bearing surfaces. We aim to assess the internalization of fluorescent polyethylene-like nanoparticles by both human macrophages and osteoclasts and also, to determine their effects in osteoclastogenesis in vitro. Human macrophages and osteoclasts were incubated with several ratios of fluorescent polyethylene-like nanoparticles between 1 and 72 h, and 4 h, 2, 4, 6, and 9 days, respectively. The internalization of nanoparticles was quantified by flow cytometry and followed by both confocal and video time-lapse microscopy. Osteoclast differentiation and activity was semiquantified by tartrate-resistant acid phosphatase (TRAP) staining, TRAP mRNA relative expression, and pit resorption assay, respectively. Macrophages, osteoclast precursors and mature osteoclasts internalized nanoparticles in a dose- and time-dependent manner and maintained their resorptive activity. In addition, nanoparticles significantly increased the osteoclastogenesis as shown by upregulation of the TRAP expressing cell number. We conclude that polyethylene-like nanosized wear particles promote osteoclast differentiation without alteration of bone resorptive activity of mature osteoclasts and they could be considered as important actors in periprosthetic osteolysis of the last new generation of polymer-bearing surfaces. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2649-2657, 2016.

BACKGROUND: Neuroimmune interactions are essential to maintain gut homeostasis and prevent intestinal disorders but so far, the impact of enteric glial cells (EGC) on immune cells remains a relatively unexplored area of research. As a dysregulation of critical cytokines such as interleukine-7 (IL-7) was suggested to exacerbate gut chronic inflammation, we investigated whether EGC could be a source of IL-7 in the gastrointestinal tract. METHODS: Expression of IL-7 in the rat enteric nervous system was analyzed by immunochemistry and Q-PCR. IL-7 variants were cloned and specific antibodies against rat IL-7 isoforms were raised to characterize their expression in the submucosal plexus. IL-7 isoforms were produced in vitro to analyze their impact on T-cell survival. KEY RESULTS: Neurons and glial cells of the rat enteric nervous system expressed IL-7 at both mRNA and protein levels. Novel rat IL-7 isoforms with distinct C-terminal parts were detected. Three of these isoforms were found in EGC or in both enteric neurons and EGC. Exposure of EGC to pro-inflammatory cytokines (IL-1β and/or TNFα) induced an upregulation of all IL-7 isoforms. Interestingly, time-course and intensity of the upregulation varied according to the presence or absence of exon 5a in IL-7 variants. Functional analysis on T lymphocytes revealed that only canonical IL-7 protects T cells from cell death. CONCLUSIONS AND INFERENCES: IL-7 and its variants are expressed by neurons and glial cells in the enteric nervous system. Their distinct expression and upregulation in inflammatory conditions suggest a role in gut homeostasis which could be critical in case of chronic inflammatory diseases.

Maternal diet during pregnancy and early postnatal life influences the setting up of normal physiological functions in the offspring. Epigenetic mechanisms regulate cell differentiation during embryonic development and may mediate gene/environment interactions. We showed here that high methyl donors associated with normal protein content in maternal diet increased the in vitro proliferation rate of neural stem/progenitor cells isolated from rat E19 fetuses. Gene expression on whole hippocampi at weaning confirmed this effect as evidenced by the higher expression of the Nestin and Igf2 genes, suggesting a higher amount of undifferentiated precursor cells. Additionally, protein restriction reduced the expression of the insulin receptor gene, which is essential to the action of IGFII. Inhibition of DNA methylation in neural stem/progenitor cells in vitro increased the expression of the astrocyte-specific Gfap gene and decreased the expression of the neuron-specific Dcx gene, suggesting an impact on cell differentiation. Our data suggest a complex interaction between methyl donors and protein content in maternal diet that influence the expression of major growth factors and their receptors and therefore impact the proliferation and differentiation capacities of neural stem cells, either through external hormone signals or internal genomic regulation.

// Solenne Dumont 1, * , Soazig Le Pennec 2, * , Audrey Donnart 1 , Raluca Teusan 1 , Marja Steenman 1 , Catherine Chevalier 3 , R&eacute;mi Houlgatte 4 and Fr&eacute;d&eacute;rique Savagner 2 1 L&rsquo;institut du Thorax, INSERM, CNRS, UNIV Nantes, BP 70721, 44007 NANTES Cedex 1, France 2 Inserm UMR 1048, I2MC, 31432 TOULOUSE Cedex 4, France 3 UMS 016, SFR Sant&eacute;, IRS UN, BP 70721, 44007 NANTES Cedex 1, France 4 Inserm UMR 954, Facult&eacute; de M&eacute;decine, BP 184, 54505 VANDOEUVRE-L&Egrave;S-NANCY Cedex, France * These authors have contributed equally to this work Correspondence to: Fr&eacute;d&eacute;rique Savagner, email: Frederique.savagner@inserm.fr Keywords: PGC-1-related coactivator; transcription factors; miRNAs; integrative network Received: November 08, 2017&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Accepted: February 26, 2018&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Published: March 23, 2018 ABSTRACT The PGC-1 (Peroxisome proliferator-activated receptor Gamma Coactivator-1) family of coactivators (PGC-1&alpha;, PGC-1&beta;, and PRC) plays a central role in the transcriptional control of mitochondrial biogenesis and oxidative phosphorylation (OXPHOS) processes. These coactivators integrate mitochondrial energy production into cell metabolism using complementary pathways. The XTC.UC1 cell line is a mitochondria-rich model of thyroid tumors whose biogenesis is almost exclusively dependent on PRC. Here we aim to propose an integrative view of the cellular pathways regulated by PRC through integration of cDNA and miRNA microarray data and chromatin immunoprecipitation results obtained from XTC.UC1 cells invalidated for PRC. This study showes that PRC induces a complex network of cellular functions interacting with at least one to five of the studied transcription factors (Estrogen Related Receptor alpha, ERR1; Nuclear-Respiratory Factors, NRF1 and NRF2; cAMP Response Element Binding, CREB; and Ying Yang, YY1). Our data confirm that ERR1 is a key partner of PRC in the regulation of mitochondrial functions and suggest a potential role of this complex in RNA processing. PRC is also involved in transcriptional regulatory complexes targeting 12 miRNAs, five of which are involved in the control of the OXPHOS process. Our findings demonstrate that the PRC coactivator can act in complex with several transcription factors and regulate miRNA expression to control the fine regulation of main metabolic functions in the cell. Therefore, in PGC-1&alpha;/&beta;-associated pathologies, PRC, as a metabolic sensor, may ensure mitochondrial homeostasis.

Ever since the first publication of the standard communication protocol for computer-assisted electrocardiography (SCP-ECG), prENV 1064, in 1993, by the European Committee for Standardization (CEN), SCP-ECG has become a leading example in health informatics, enabling open, secure, and well-documented digital data exchange at a low cost, for quick and efficient cardiovascular disease detection and management. Based on the experiences gained, since the 1970s, in computerized electrocardiology, and on the results achieved by the pioneering, international cooperative research on common standards for quantitative electrocardiography (CSE), SCP-ECG was designed, from the beginning, to empower personalized medicine, thanks to serial ECG analysis. The fundamental concept behind SCP-ECG is to convey the necessary information for ECG re-analysis, serial comparison, and interpretation, and to structure the ECG data and metadata in sections that are mostly optional in order to fit all use cases. SCP-ECG is open to the storage of the ECG signal and ECG measurement data, whatever the ECG recording modality or computation method, and can store the over-reading trails and ECG annotations, as well as any computerized or medical interpretation reports. Only the encoding syntax and the semantics of the ECG descriptors and of the diagnosis codes are standardized. We present all of the landmarks in the development and publication of SCP-ECG, from the early 1990s to the 2009 International Organization for Standardization (ISO) SCP-ECG standards, including the latest version published by CEN in 2020, which now encompasses rest and stress ECGs, Holter recordings, and protocol-based trials.