Éditeur(s) : HAL CCSD
Résumé : International audience
Congrès ADELF – SFSP 2017
Amiens, France

hal-01682297
https://hal-ehesp.archives-ouvertes.fr/hal-01682297

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
STUDY QUESTION: Can protein biomarkers of the male genital tract be identified in human seminal plasma? SUMMARY ANSWER: We identified potential biomarkers for each of the organs participating in the secretions of the human seminal plasma. WHAT IS KNOWN ALREADY: The seminal plasma fulfills critical functions for fertility by providing spermatozoa with a protective milieu, promoting their final maturation and modulating the immune responsiveness of the female reproductive tract. It is also considered to be a promising source of biomarkers of male infertility and/or pathologies of the male genital tract. STUDY DESIGN, SIZE, DURATION: This study combines proteomic analyses of normal seminal plasma together with transcriptomic gene expression profiling of human healthy tissues. MATERIALS, SETTING, METHODS: Non-liquefied seminal plasma proteins from a healthy donor were prefractionated using two sequential Proteominer™ libraries. Eight subproteome fractions were collected, trypsin digested and subjected to three successive mass spectrometry analyses for peptide characterization. The list of identified proteins was compared with and merged with other available data sets of the human seminal plasma proteome. The expression of corresponding genes was then investigated using tissue transcriptome profiles to determine where, along the male reproductive tract, these proteins were produced. Finally, tissue specificity of a selected subset of biomarker candidates was validated on human tissues. MAIN RESULTS AND THE ROLE OF CHANCE: We first performed a proteomic analysis of the human seminal plasma and identified 699 proteins. By comparing our protein list with other previous proteomic data sets, we found that 2545 unique proteins have been described so far in the human seminal plasma. We then profiled their expression at the gene level and identified 83 testis, 42 epididymis, 7 seminal vesicle and 17 prostate candidate protein markers. For a subset of testis-specific candidates, i.e. TKTL1, LDHC and PGK2, we further validated their germ cell expression and demonstrated that such markers could distinguish between semen from fertile and infertile men. LIMITATIONS, REASONS FOR CAUTION: While some of the markers we identified are well-known tissue-specific products, further dedicated studies to validate the biomarker status of new candidates will be required. Additionally, whether or not the abundance of these proteins is indeed decreased in some specific pathological situations remains to be determined. WIDER IMPLICATIONS OF THE FINDINGS: Using an integrative genomics approach, we identified biomarker candidates for each of the organs participating in the seminal plasma production. In this study, we essentially focused on germ cell markers and their potential application for the diagnosis of male infertility. Other types of markers also deserve a focused attention given their potential predictive value for various reproductive disorders, notably for prostate cancers. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the Proteomics Core Facility at Biogenouest and was funded by Conseil Régional de Bretagne, IBiSA and Agence de la Biomédecine grants. The authors declare that there exists a competing financial interest in this work that is related to a patent application on the use of identified germ cell-specific proteins in an antibody-based assay (Fertichip™) to predict the successful testicular biopsy outcomes in human non-obstructive azoospermia.
ISSN: 0268-1161

inserm-00814146
http://www.hal.inserm.fr/inserm-00814146
DOI : 10.1093/humrep/des360
PUBMED : 23024119

Éditeur(s) : HAL CCSD Elsevier Masson
Résumé : International audience
ISSN: 1631-0691

hal-01083754
https://hal-agroparistech.archives-ouvertes.fr/hal-01083754
DOI : 10.1016/j.crvi.2009.01.006

Éditeur(s) : HAL CCSD Ferrata Storti Foundation
Résumé : International audience
Lionnet et al. recently reported a high prevalence of retinopathy (RET) and otologic disorders (OTD) in patients with sickle cell-hemoglobin C disease (SC), while a significant number of patients had renal diseases (mainly glomerulopathy; GLO) and osteonecrosis (OST). The pathophysiological processes of these complications in SC are not well defined, although blood hyperviscosity has been suspected, but never tested to the best of our knowledge, as responsible for several chronic complications in SC disease1,2. The aim of this study was to analyze the associations between hematological and hemorheological parameters and chronic complications in adult SC patients.
ISSN: 0390-6078

inserm-01081709
http://www.hal.inserm.fr/inserm-01081709
http://www.hal.inserm.fr/inserm-01081709/document
http://www.hal.inserm.fr/inserm-01081709/file/2014%2C%20Lemonne%20-%20Impaired%20blood%20rheology%20plays%20a%20role%20in%20the%20chronic%20disorders%20associated%20with%20sickle%20cell-hemoglobin%20C%20disease.pdf
PUBMED : 24633868

Éditeur(s) : HAL CCSD Oldendorf/Luhe
Résumé : International audience
Large filamentous sulfur-oxidizing bacteria belonging to the Beggiatoacae family can cover large portions of shallow marine sediments surrounding mangroves in Guadeloupe (French West Indies). In order to assess the importance of Beggiatoa mats as an infaunal food source, observations were conducted of the area within mats and at increasing distances from mats. We used natural isotopic compositions and a C-13 enrichment study. Both revealed an ingestion of bacterial mats by associated meiofauna, dominated by rotifers and to a smaller extent by small polychaetes and nematodes. Compared to adjacent sites, sediment covered by bacterial mats presented a higher abundance of diatoms, whereas the total biomass of bacteria did not vary. This constant bacterial abundance suggests that the proportion of organic matter represented by sulfur bacteria is limited compared to the fraction of total bacteria. There was no significant difference in infaunal abundance in mats, suggesting that the availability of this chemosynthetic food resource had a limited local effect. Grazers presented a delta C-13 value increasing with distance from the mat. However, isotopic composition of phospholipid-derived fatty acids specific for diatoms and bacteria revealed that this change is related to modifications of delta C-13 dietary components rather than to changes in diet composition. These complementary methods revealed that the occurrence of sulfur-oxidizing bacterial mats does not necessarily affect grazer abundance and importance of bacteria in their diet. Despite its wide occurrence, Beggiatoa mats would consequently have a minor influence on the structure of the mangrove food web.
ISSN: 0171-8630

hal-01545912
https://hal.archives-ouvertes.fr/hal-01545912
DOI : 10.3354/meps11035

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ISSN: 0020-7292

inserm-01065103
http://www.hal.inserm.fr/inserm-01065103
http://www.hal.inserm.fr/inserm-01065103/document
http://www.hal.inserm.fr/inserm-01065103/file/Figure.pdf
http://www.hal.inserm.fr/inserm-01065103/file/2013_Douine_-_Survival_cervical.pdf

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BACKGROUND: Estrogen receptors (ER) α and β are found in both women and men in many tissues, where they have different functions, including having roles in cell proliferation and differentiation of the reproductive tract. In addition to estradiol (E2), a natural hormone, numerous compounds are able to bind ERs and modulate their activities. Among these compounds, phytoestrogens such as isoflavones, which are found in plants, are promising therapeutics for several pathologies. Glyceollins are second metabolites of isoflavones that are mainly produced in soybean in response to an elicitor. They have potentially therapeutic actions in breast cancer by reducing the proliferation of cancer cells. However, the molecular mechanisms driving these effects remain elusive. METHODS: First, to determine the proliferative or anti-proliferative effects of glyceollins, in vivo and in vitro approaches were used. The length of epithelial duct in mammary gland as well as uterotrophy after treatment by E2 and glyceollins and their effect on proliferation of different breast cell line were assessed. Secondly, the ability of glyceollin to activate ER was assessed by luciferase assay. Finally, to unravel molecular mechanisms involved by glyceollins, transcriptomic analysis was performed on MCF-7 breast cancer cells. RESULTS: In this study, we show that synthetic versions of glyceollin I and II exert anti-proliferative effects in vivo in mouse mammary glands and in vitro in different ER-positive and ER-negative breast cell lines. Using transcriptomic analysis, we produce for the first time an integrated view of gene regulation in response to glyceollins and reveal that these phytochemicals act through at least two major pathways. One pathway involving FOXM1 and ERα is directly linked to proliferation. The other involves the HIF family and reveals that stress is a potential factor in the anti-proliferative effects of glyceollins due to its role in increasing the expression of REDD1, an mTORC1 inhibitor. CONCLUSION: Overall, our study clearly shows that glyceollins exert anti-proliferative effects by reducing the expression of genes encoding cell cycle and mitosis-associated factors and biomarkers overexpressed in cancers and by increasing the expression of growth arrest-related genes. These results reinforce the therapeutic potential of glyceollins for breast cancer.
ISSN: 1478-811X

hal-01560288
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01560288
DOI : 10.1186/s12964-017-0182-1
PUBMED : 28666461

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
This study investigated the clinical epidemiology and resistance mechanisms of Acinetobacter baumannii and characterised the clonal diversity of carbapenem-resistant A. baumannii (CRAB) during an ICU-associated outbreak at Cayenne Hospital, French Guiana. All non-duplicate A. baumannii isolates from 2008 to 2014 were tested for antibiotic susceptibility by disk diffusion. Multilocus sequence typing, pulsed-field gel electrophoresis (PFGE) and characterisation of carbapenemase-encoding genes were performed on CRAB. Of the 441 A. baumannii isolates, most were from males (54.0%) and were detected mainly from the ICU (30.8%) and medicine wards (21.8%). In the ICU, strains were mainly isolated from the respiratory tract (44.1%) and bloodstream (14.0%), whereas in medicine wards they mainly were from wound/drainage (36.5%) and bloodstream (25.0%). A. baumannii showed the greatest susceptibility to piperacillin/tazobactam (92.7%), imipenem (92.5%), colistin (95.6%) and amikacin (97.2%), being lower in the ICU and medicine wards compared with other wards. An outbreak of OXA-23-producing CRAB occurred in the 13-bed ICU in 2010. CRAB strains were more co-resistant to other antimicrobials compared with non-CRAB. Molecular genetics analysis revealed five sequence types [ST78, ST107 and ST642 and two new STs (ST830 and ST831)]. Analysis of PFGE profiles indicated cross-transmissions of CRAB within the ICU, between the ICU and one medicine ward during transfer of patients, and within that medicine ward. This study provides the first clinical and molecular data of A. baumannii from French Guiana and the Amazon basin. The ICU was the highest risk unit of this nosocomial outbreak of OXA-23-producing CRAB, which could subsequently disseminate within the hospital.
ISSN: 0924-8579

hal-01506828
https://hal.archives-ouvertes.fr/hal-01506828
PUBMED : 27236843

Éditeur(s) : HAL CCSD
Résumé : International audience
Background Orodental diseases include several clinically and genetically heterogeneous disorders that can present in isolation or as part of a genetic syndrome. Due to the vast number of genes implicated in these disorders, establishing a molecular diagnosis can be challenging. We aimed to develop a targeted next-generation sequencing (NGS) assay to diagnose mutations and potentially identify novel genes mutated in this group of disorders. Methods We designed an NGS gene panel that targets 585 known and candidate genes in orodental disease. We screened a cohort of 101 unrelated patients without a molecular diagnosis referred to the Reference Centre for Oro-Dental Manifestations of Rare Diseases, Strasbourg, France, for a variety of orodental disorders including isolated and syndromic amelogenesis imperfecta (AI), isolated and syndromic selective tooth agenesis (STHAG), isolated and syndromic dentinogenesis imperfecta, isolated dentin dysplasia, otodental dysplasia and primary failure of tooth eruption. Results We discovered 21 novel pathogenic variants and identified the causative mutation in 39 unrelated patients in known genes (overall diagnostic rate: 39%). Among the largest subcohorts of patients with isolated AI (50 unrelated patients) and isolated STHAG (21 unrelated patients), we had a definitive diagnosis in 14 (27%) and 15 cases (71%), respectively. Surprisingly, COL17A1 mutations accounted for the majority of autosomal-dominant AI cases. Conclusions We have developed a novel targeted NGS assay for the efficient molecular diagnosis of a wide variety of orodental diseases. Furthermore, our panel will contribute to better understanding the contribution of these genes to orodental disease. Trial registration numbers NCT01746121 and NCT02397824
Journal of Medical Genetics

hal-01272929
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01272929
DOI : 10.1136/jmedgenet-2015-103302
PUBMED : 26502894

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
The prognosis of vertebral alveolar echinococcosis (AE) is poor. We report on the unique outcome of a patient with preexisting liver cirrhosis, in whom a diagnosis of vertebral AE was established on vertebral histopathology (D4 corporectomy in 2010 for paraplegia). Therapeutic drug monitoring of albendazole (ABZ) showed that a low dosage was appropriate. The patient recovered and ABZ withdrawal was decided in 2014, with no relapse 18 months later. In this patient, infection was purely or mainly localized in the dorsal spine, and this may have been favored by liver cirrhosis. A longer follow-up is, however, needed to confirm cure.
ISSN: 0300-8126

hal-01509561
https://hal.archives-ouvertes.fr/hal-01509561
PUBMED : 28004258

Éditeur(s) : HAL CCSD Society for the Study of Reproduction
Résumé : International audience
Matrix-assisted laser desorption/ionization (MALDI) tissue imaging mass spectrometry is particularly promising among the numerous applications of mass spectrometry. It is used for probing and analyzing the spatial arrangement of a wide range of molecules, including proteins, peptides, lipids, drugs, and metabolites, directly in thin slices of tissue. In the field of proteomics, the technology avoids tedious and time-consuming extraction and fractionation steps classically required for sample analysis. MALDI imaging mass spectrometry is increasingly recognized as a powerful method for clinical proteomics, particularly in cancer research. The technology has particular potential for the discovery of new tissue biomarker candidates, classification of tumors, early diagnosis or prognosis, elucidating pathogenesis pathways, and therapy monitoring. Over recent years, MALDI imaging mass spectrometry has been used for molecular profiling and imaging directly in male and female reproductive tissues. This review will consider some of the recent publications in the field, addressing a range of issues covering embryo development, gene expression product profiling during gametogenesis, and seeking and identifying biomarkers of reproductive cancers. The wealth of advances in mass spectrometry imaging will inevitably attract biologists and clinicians as the advantages and power of this technology become more widely known. This review will also discuss bottlenecks and the many technical issues that remain to be resolved before laboratories in the field can adopt the technology. We foresee that MALDI imaging mass spectrometry will have a major impact in reproductive research by opening new avenues to the understanding of various molecular mechanisms and the diagnosis of reproductive pathologies.
ISSN: 0006-3363

hal-00877851
https://hal.archives-ouvertes.fr/hal-00877851
DOI : 10.1095/biolreprod.111.094896
PUBMED : 22156474

Éditeur(s) : HAL CCSD
Résumé : 20 pp
We first analyze some atmospheric parameters measured in 2004 at the top of La Soufrière volcano: wind speed, pressure and temperature. Next, we study the stochastic process of the wind speed modulus which is of interest for prediction of pollution induced by the plume. We fit to the data various models : FARIMA, periodic trend plus multifractional Brownian noise, multifractal continuous cascades. The estimations show that they evoluate during some transition phases in response to environment changes. Thus, we finally suggest, for future works, some settings that should be more appropriate: time series with regime changes and stochastic processes in random environment.
https://hal.archives-ouvertes.fr/hal-00165572

hal-00165572
https://hal.archives-ouvertes.fr/hal-00165572
https://hal.archives-ouvertes.fr/hal-00165572/document
https://hal.archives-ouvertes.fr/hal-00165572/file/Windsouf_v11.pdf

Éditeur(s) : HAL CCSD American Diabetes Association
Résumé : International audience
OBJECTIVE: To compare incidences and risk factors for diabetes using seven definitions, with combinations of pharmacological treatment, fasting plasma glucose (FPG) ≥7.0 mmol/L, and HbA(1c) ≥6.5%. RESEARCH DESIGN AND METHODS: Participants aged 30-65 years from the Data from an Epidemiological Study on the Insulin Resistance Syndrome (DESIR) cohort were followed for 9 years. RESULTS: More men had incident diabetes as defined by FPG ≥7.0 mmol/L and/or treatment than by HbA(1c) ≥6.5% and/or treatment: 7.5% (140/1,867) and 5.3% (99/1,874), respectively (P < 0.009); for women incidences were similar: 3.2% (63/1,958) and 3.4% (66/1,954). Known risk factors predicted diabetes for almost all definitions. Among those with incident diabetes by FPG alone versus HbA(1c) alone, there were more men (78 vs. 35%), case patients were 8 years younger, and fewer were alcohol abstainers (12 vs. 35%) (all P < 0.005). A diabetes risk score discriminated well between those with and without incident diabetes for all definitions. CONCLUSIONS: In men, FPG definitions yielded more incident cases of diabetes than HbA(1c) definitions, in contrast with women. An FPG-derived risk score remained relevant for HbA(1c)-defined diabetes.
Diabetes Care

inserm-00739799
http://www.hal.inserm.fr/inserm-00739799
http://www.hal.inserm.fr/inserm-00739799/document
DOI : 10.2337/dc10-1581
PUBMED : 21346181

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
We assessed the occurrence of algae in five species of tank-bromeliads found in contrasting environmental sites in a Neotropical, primary rainforest around the Nouragues Research Station, French Guiana. The distributions of both algal abundance and biomass were examined based on physical parameters, the morphological characteristics of bromeliad species and with regard to the structure of other aquatic microbial communities held in the tanks. Algae were retrieved in all of the bromeliad species with mean densities ranging from ∼10(2) to 10(4) cells/mL. Their biomass was positively correlated to light exposure and bacterial biomass. Algae represented a tiny component of the detrital food web in shaded bromeliads but accounted for up to 30 percent of the living microbial carbon in the tanks of Catopsis berteroniana, located in a highly exposed area. Thus, while nutrient supplies are believed to originate from wind-borne particles and trapped insects (i.e., allochtonous organic matter), our results indicate that primary producers (i.e., autochtonous organic matter) are present in this insectivorous bromeliad. Using a 24-h incubation of size-fractionated and manipulated samples from this plant, we evaluated the impact of mosquito foraging on algae, other microorganisms and rotifers. The prey assemblages were greatly altered by the predation of mosquito larvae. Grazing losses indicated that the dominant algal taxon, Bumilleriopsis sp., like protozoa and rotifers, is a significant part of the diet of mosquito larvae. We conclude that algae are a relevant functional community of the aquatic food web in C. berteroniana and might form the basis of a complementary non-detrital food web.
ISSN: 1932-6203

hal-00819161
https://hal.archives-ouvertes.fr/hal-00819161
https://hal.archives-ouvertes.fr/hal-00819161/document
https://hal.archives-ouvertes.fr/hal-00819161/file/Brouard2011_AreAlgae.pdf
DOI : 10.1371/journal.pone.0020129

Éditeur(s) : HAL CCSD American Society of Hematology
Résumé : International audience
Polycythemia vera (PV) is characterized by an increased RBC mass, spontaneous erythroid colony formation, and the JAK2V617F mutation. PV is associated with a high risk of mesenteric and cerebral thrombosis. PV RBC adhesion to endothelial laminin is increased and mediated by phosphorylated erythroid Lu/BCAM. In the present work, we investigated the mechanism responsible for Lu/BCAM phosphorylation in the presence of JAK2V617F using HEL and BaF3 cell lines as well as RBCs from patients with PV. High levels of Rap1-GTP were found in HEL and BaF3 cells expressing JAK2V617F compared with BaF3 cells with wild-type JAK2. This finding was associated with increased Akt activity, Lu/BCAM phosphorylation, and cell adhesion to laminin that were inhibited by the dominant-negative Rap1S17N or by the specific Rap1 inhibitor GGTI-298. Surprisingly, knocking-down EpoR in HEL cells did not alter Akt activity or cell adhesion to laminin. Our findings reveal a novel EpoR-independent Rap1/Akt signaling pathway that is activated by JAK2V617F in circulating PV RBCs and responsible for Lu/BCAM activation. This new characteristic of JAK2V617F could play a critical role in initiating abnormal interactions among circulating and endothelial cells in patients with PV.
ISSN: 0006-4971

inserm-00821109
http://www.hal.inserm.fr/inserm-00821109
http://www.hal.inserm.fr/inserm-00821109/document
http://www.hal.inserm.fr/inserm-00821109/file/De_Grandis_Blood_2013.pdf
DOI : 10.1182/blood-2012-07-440487

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
BACKGROUND: Estrogens are thought to play a critical role in prostate carcinogenesis. It has been suggested that polymorphisms of genes encoding enzymes involved in estrogen metabolism are risk factors for prostate cancer. However, few studies have been performed on populations of African ancestry, which are known to have a high risk of prostate cancer. OBJECTIVE: We investigated whether functional polymorphisms of CYP17, CYP19, CYP1B1, COMT and UGT1A1 affected the risk of prostate cancer in two different populations of African ancestry. METHODS: In Guadeloupe (French West Indies), we compared 498 prostate cancer patients and 565 control subjects. In Kinshasa (Democratic Republic of Congo), 162 prostate cancer patients were compared with 144 controls. Gene polymorphisms were determined by the SNaPshot technique or short tandem repeat PCR analysis. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). RESULTS: The AA genotype and the A allele of rs4680 (COMT) appeared to be inversely associated with the risk of prostate cancer in adjusted models for both Afro-Caribbean and native African men. For the A allele, a significant inverse association was observed among cases with low-grade Gleason scores and localized clinical stage, in both populations. CONCLUSIONS: These preliminary results support the hypothesis that polymorphisms of genes encoding enzymes involved in estrogen metabolism may modulate the risk of prostate cancer in populations of African ancestry
ISSN: 1932-6203

hal-01305477
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01305477
DOI : 10.1371/journal.pone.0153609
PUBMED : 27074016

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BACKGROUND:In French Guiana, a French overseas territory in South America, 6 to 10 thousands undocumented persons work illegally in gold mining sites in the Amazonian forest. Precarious life conditions lead to poor health but few data exist on the health status of illegal gold miners in French Guiana. The objective of this article was to describe the sociodemographic and health status of this vulnerable population.METHOD:A prospective cross-sectional survey was conducted in 2015 on gold mine supply sites at the border between French Guiana and Suriname. Health status was assessed through medical examination, past medical history, haemoglobin concentration, and HIV and malaria testing. A questionnaire was used to collect data about the migration itinerary and life conditions on mining sites.RESULTS:Among the 421 adults included in the study, 93.8% (395/421) were Brazilian, mainly from Maranhão (55.7%, 220/395), the poorest Brazilian state. The sex ratio was 2.4. Overall, 48% of persons never went to school or beyond the primary level. The median time spent in gold mining was quite long (10 years), with a high turn-over. One third of the surveyed population (37.1%, 156/421) had high blood pressure, and only two had a medical follow-up. Most persons had experienced malaria (89.3%, 376/421). They declared frequent arboviroses and digestive disorders. Active leishmaniasis was observed in 8.3% of gold miners. Among women, 28.5% were anemic. Concerning HIV, 36.6% (154/421) of persons, mainly men, never got tested before and 6 were tested positive, which represented an HIV prevalence of 1.43% (95%CI =0.29-2.5).CONCLUSION:These findings support the hypothesis that mining in remote areas is linked to several specific illnesses. Theoretically, gold miners would be presumed to start their economical migration to French Guiana as a healthy group. However, their strenuous working and living conditions there lead to poor health caused by infectious and non infectious diseases. This description of their health status is precious for health policy planners in French Guiana given the importance of controlling communicable disease, and the severity and range of specific illnesses acquired by this neglected population.TRIAL REGISTRATION:Clinical trial registration PRS N° NCT02903706 . Retrospectively registered 09/13/2016.
ISSN: 1471-2458

inserm-01566314
http://www.hal.inserm.fr/inserm-01566314
http://www.hal.inserm.fr/inserm-01566314/document
http://www.hal.inserm.fr/inserm-01566314/file/2017%2C%20Douine%20-%20Illegal%20gold%20miners%20in%20French%20Guiana.pdf
DOI : 10.1016/S0140-6736(10)62169-1

Éditeur(s) : HAL CCSD
Résumé : National audience
Atelier "Fouille de Données Complexes" (EGC'2009)

hal-00466057
https://hal.archives-ouvertes.fr/hal-00466057

Éditeur(s) : HAL CCSD Impact journals
Résumé : International audience
Interleukin (IL)-33 has been recently reported to be strongly pro-fibrogenic in various models of liver disease. Our aim was to study the role of endogenous IL-33 in a diet-induced model of steatohepatitis. IL-33 deficient mice and wild type (WT) littermates received a high-fat diet (HFD), or a standard diet for 12 weeks. The HFD-induced steatohepatitis was associated with an upregulation of IL-33 transcripts and protein. An insulin tolerance test revealed lower systemic insulin sensitivity in IL33-/-HFD mice than in WT-HFD mice. Nevertheless, IL-33 deficiency did not affect the severity of liver inflammation by histological and transcriptomic analyses, nor the quantity of liver fibrosis. Livers from HFD mice had more myeloid populations, markedly fewer NKT cells and higher proportion of ST2+ Treg cells and ST2+ type 2 innate lymphoid cells (ILC2), all unaffected by IL-33 deficiency. In conclusion, deficiency of endogenous IL-33 does not affect the evolution of experimental diet-induced steatohepatitis towards liver fibrosis.
ISSN: 1949-2553

hal-01578584
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01578584
DOI : 10.18632/oncotarget.18335
PUBMED : 28611297

Éditeur(s) : HAL CCSD Wiley
Résumé : Unveiling the genetic basis of local adaptation to environmental variation is a major goal in molecular ecology. In rugged landscapes characterized by environmental mosaics, living populations and communities can experience steep ecological gradients over very short geographical distances. In lowland tropical forests, interspecific divergence in edaphic specialization (for seasonally flooded bottomlands and seasonally dry terra firme soils) has been proven by ecological studies on adaptive traits. Some species are nevertheless capable of covering the entire span of the gradient; intraspecific variation for adaptation to contrasting conditions may explain the distribution of such ecological generalists. We investigated whether local divergence happens at small spatial scales in two stands of Eperua falcata (Fabaceae), a widespread tree species of the Guiana Shield. We investigated Single Nucleotide Polymorphisms (SNP) and sequence divergence as well as spatial genetic structure (SGS) at four genes putatively involved in stress response and three genes with unknown function. Significant genetic differentiation was observed among sub-populations within stands, and eight SNP loci showed patterns compatible with disruptive selection. SGS analysis showed genetic turnover along the gradients at three loci, and at least one haplotype was found to be in repulsion with one habitat. Taken together, these results suggest genetic differentiation at small spatial scale in spite of gene flow. We hypothesize that heterogeneous environments may cause molecular divergence, possibly associated to local adaptation in E. falcata.
ISSN: 1010-061X

hal-01032412
https://hal.archives-ouvertes.fr/hal-01032412
DOI : 10.1111/jeb.12069