Evidence from genetic and molecular investigations strongly suggests an etiological relationship between asthma and obesity. Genome-wide association studies (GWAS) have identified common risk loci for these diseases, which share alterations in immunological mechanisms and changes in both gut microbiome architecture and microbial metabolites. These observations suggest evidence of cross phenotype associations (pleiotropy) in asthma and obesity. We aim to define new biological mechanisms underlying common risk of asthma and obesity through combined genetic and metabolomic analyses in the Epidemiological study on the Genetics and Environment of Asthma (EGEA, n=1,400), followed by similar analyses in an independent cohort (the Saguenay-Lac-Saint-Jean, SLSJ n=1,200) to assess robustness of results and by characterisation of the biological roles of metabolites associated with asthma and obesity in a mouse model relevant to these diseases. Metabolomic profiling will apply both untargeted approaches (1H-Nuclear Magnetic Resonance -NMR and mass spectrometry -MS), which will generate quantitative data for about 5,000 (MS) and 15,000 (NMR) spectral signals, and a targeted platform (Metabolon), which will assist metabolite attribution in NMR and MS datasets. We will carry out metabolome wide association studies (MWAS) to test associations between metabolites and asthma and adiposity phenotypes, examined jointly, in EGEA in order to define biomarkers associated with these two phenotypes. We will take advantage of SNP-based genome-wide genotype data already available in EGEA to carry out GWAS of metabolome quantitative data in order to localise genes associated with changes in metabolite abundance and underlying shared risk of asthma and adiposity. We will apply Mendelian randomization methods to identify metabolites with a causal effect on asthma and adiposity. Follow up metabolome and genetic analyses will be carried out in SLSJ in order to assess robustness of results from MWAS and GWAS in EGEA. Finally, the concepts elaborated in humans will be tested in vivo in a mouse model of asthma and obesity induced experimentally, which will be treated chronically by candidate metabolites in order to test their biological effects on obesity and asthma endophenotypes and analyse molecular (metabolome, transcriptome) consequences. Ultimately, METABASTHMA will add new and relevant components to existing asthma genetics and epidemiology by generating full resolution metabolomic profiles from individuals with asthma accompanying inflammation and obesity. It will deliver novel knowledge of diagnostic metabolic biomarkers, including metabolic products of gut microbial activity, at the crossroads between host susceptibility alleles, lifestyle and environmental exposures that will provide a framework to predict risk of asthma and obesity.

Amyloid deposition in pancreatic islets, formed from islet amyloid polypeptide (amylin), is a common pathologic feature of type 2 diabetes mellitus (T2DM) found in more than 90% of T2DM patients. The non-invasive, repeatable, in vivo imaging visualization of amylin aggregates would be an invaluable tool for early diagnosis of T2DM, but also for the evaluation of potential anti-amyloid therapies; however, today it represents an unmet need. We propose the design, synthesis, in vitro and in vivo validation of imaging probes based on metal complexes for the detection of amylin aggregates. We will use a modular approach to create these probes where a targeting unit, capable of selective binding to the amylin aggregates is linked to a metal chelate which acts as an imaging reporter. The major advantage of this approach is that a large number of metal ions exist that can be used as imaging probes for a variety of imaging modalities. The most important are Gd3+ for MRI detection, and various radioactive isotopes for nuclear imaging. Several of these metal ions applicable as probes in the different imaging modalities have similar coordination chemistry characteristics and therefore can be easily substituted one by another in their complexes. Consequently, we can create a platform of imaging agents for various modalities by using the same chelator and targeting unit and choosing the appropriate metal ion for the imaging probe. In this project, the in vivo evaluation will be focused on MR imaging with the Gd3+ and SPECT imaging with the 111In3+ analogues, using appropriate mice models. Indeed, longitudinal and pathological studies of pancreas morphology are nearly impossible in humans, therefore we will mimic pancreatic amylin aggregates in mice models. It will allow us to run longitudinal studies with a significant number of animals per group. This interdisciplinary project combines chemistry and biology and proposes an innovative imaging approach based on novel imaging agents with possible future human applications. First, the results will contribute to a better understanding of the interactions at the molecular level between metal-complexes as imaging probes and amyloid-type peptides. The in vivo data will validate the potential of these probes as imaging agents in T2DM. On a longer term, the results of this project can contribute to propose a solution to an identified but unmet medical need, as so far no specific MRI agents have been reported for amylin visualization in T2DM.

Pluripotency is the term used to describe the ability of a stem cell to give rise to all cell types in mature organisms. Pluripotent stem cells (PSCs) in mice comprise the following two main types: (i) embryonic stem cells (mESCs), derived from the early epiblast of the blastocyst, which epitomise the naïve (or ground) state of pluripotency, and (ii) epiblast stem cells (EpiSCs), derived from the late epiblast of the egg cylinder–stage embryo, which epitomise the primed state of pluripotency. Only the naïve mESCs can colonise the epiblast of the blastocyst, contribute to the development of all tissue types and generate chimeras; PSCs in the primed state cannot. Thus, chimeric competency is a hallmark of naïve pluripotency. PSC lines established in other mammals, such as primates and rabbits, display nearly all the characteristic features of primed pluripotency although they are generated from the early epiblast of the blastocyst, similar to rodent ESCs. In non-rodent species, including humans, it is challenging to capture the original state of pluripotency of early epiblast cells in PSCs. In particular, the scarcity of primate embryos makes it difficult to address this issue. As a surrogate model, the rabbit is perfectly suited to explore the nature and mechanisms of acquisition and maintenance of pluripotency in the epiblast cells and ESCs for a wide range of non-rodent mammals, including primates. The aim of our proposal is to explore naïve pluripotency and chimeric competency in the rabbit. The project’s main objectives are to (1) characterise the transcriptome of the rabbit epiblast throughout pre-implantation development and identify rabbit-specific markers of naïve pluripotency using single-embryo and single-cell RNA sequencing (RNA-seq), (2) identify new genes and small molecules for reprogramming conventional rabbit PSCs to naïve-state pluripotency and (3) capture naïve-state pluripotency from pre-implantation rabbit embryos using the identified markers and molecules. To achieve these objectives, the following two complementary approaches will be implemented: (i) unbiased screening of a library of lentiviral vectors that express transcription factors, histone-modifying enzymes and chromatin-remodelling factors, and (ii) high-throughput screening of a small-molecule library. From this study using the rabbit model, we will glean new information about the naive state of pluripotency in primates, which would be applicable to the generation of somatic chimeras in monkeys. The project comprises four partners with complementary expertise. Pierre Savatier (Stem Cell and Brain Research Institute, INSERM; Partner 1) has extensive expertise in the study of PSCs in the mouse, macaque, human and rabbit. P. Savatier recently developed the tools and methods for testing chimeric competency of PSCs using pre-implantation rabbit embryos. Veronique Duranthon (INRA; Partner 2) has extensive expertise in the molecular analysis of pre-implantation mammalian embryos at both the genomic and epigenetic levels and was first to publish a characterisation of the rabbit epiblast transcriptome. V. Duranthon specialises in bioinformatics and statistical analyses of high-throughput Omics data in domestic species, including the rabbit. Dr Romeo Ricci (IGBMC; Partner 3) has gained extensive expertise in cell biology and cellular signalling by successfully using cellular-screening approaches. R. Ricci conducts genetic and chemical cellular screening in the context of stem-cell maintenance and differentiation. Dr Fredrik Lanner, assistant Professor at the Karolinska Institutet (Partner 4), has a strong background in mouse and human pluripotency and embryo development. Through single-cell RNA-seq, Dr Lanner’s laboratory has described lineage specifications in the mouse and has established a transcriptional roadmap of the human embryo that also identified bi-allelic dosage compensation as an in vivo hallmark of the naïve pluripotent state.

Neuronal cell decline in neurodegenerative disease can be caused by inherited mutations and consists of neuron dysfunction followed by neuron demise. The ability of neurons to cope with the chronic stress induced by mutant protein expression may determine the course of their decline and demise, which may impact on disease progression. Although the pathophysiological importance of neuronal stress response was previously illustrated, very little is known about the mechanisms that may regulate neuronal cell homeostasis during the early phases of the pathogenic process in neurodegenerative disease. In particular, how neuron differentiation and cell survival factors may closely interact to regulate neuron survival in neurodegenerative disease remains poorly understood. We found that a receptor important for neurogenesis is increased in several models of Huntington’s disease (HD), which may occur during the early phases of the disease process. The increase of this receptor directly represses FOXO transcription factors, a protein family that is central to cell survival/longevity and that is important to neuron homeostasis and neuroprotection. We postulate that neurons are unable to develop a fully-efficient FOXO-mediated survival response during the very early phases of the pathogenic process in HD, which may have strong therapeutic implications for the design of successful disease-modifying strategies. On these grounds, our project is to use several models of HD to further investigate how FOXO is repressed by developmental signaling in mutant polyglutamine neurons and how this may alter neuron survival genes downstream to FOXO. Our project will also investigate how the repression of FOXO may be inhibited to restore a full neuron survival ability in HD. This project is expected to advance our understanding of the regulation of neuron survival in HD and to foster the development of successful disease-modifying strategies for HD and perhaps other neurodegenerative diseases.

Nowadays, we are faced with the issue that conventional drug delivery systems must be administered systematically in high doses and tend to cause severe side-effects because of the nonspecific uptake of drugs by healthy tissues/organs. In this work, an easily controllable aerosol-based approach is proposed to produce biocompatible, mesoporous cerium oxide particle with well-controlled internal morphology and shell porosity for controlling the drug loading and release properties. Moreover, in order to have a specific release we will chemically modify these particles with modified polysaccharides (elaboration of stimuli-responsive systems). The ultimate goal of our project is to propose a theranostic platform capable of assessing diseased cells and able to deliver therapeutic molecules in a controllable way.