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Background To support internal compound development in systemic sclerosis, a study was performed to identify an mRSS signature in a longitudinal approach by analyzing skin biopsies. Objectives Identification of a gene signature that could be used as a quantitative surrogate marker for the mRSS independent of any treatment. Methods 77 forearm skin biopsies from 32 patients at baseline, and from the same patients after 8 weeks of treatment with SAR100842 (a LPA1 antagonist) or placebo (N=30) and after an additional 16 weeks of treatment with SAR100842 (N=15) in a phase 2 trial, were collected. Total RNA was extracted with the RNeasy® Fibrous Tissue Mini kit according to the manufacturer9s instructions. Total RNA was quantified by spectrofluormetry and qualified by capillary electrophoresis using Agilent Bioanalyzer 2100. Whole transcriptome analysis was performed using Affymetrix chips. Genes highly correlated (Pearson9s correlation) with the mRSS were identified at each treatment visit. A signature was identified as a set of genes whose expression levels correlated consistently either positively or negatively with the mRSS at all study visits regardless of treatment group. The correlation value between the genes and the mRSS at baseline had to be >0.5 or Results This methodology led to the identification of 64 genes considered for the signature and viewed as a single composite marker that was highly correlated to the mRSS. A principal component analysis was computed and the first component explaining the maximum variance in the signature was highly correlated to the mRSS at baseline and week 8. This correlation was confirmed with the median polish algorithm (Pearson9s correlation coefficient of -0.75 and -0.73 respectively). The most significant disease and disorder biological functions associated with the mRSS signature genes were related to immunological diseases. A significant enrichment was also detected for genes associated with inflammatory response and connective tissue disorders with p-values from 2.98E-05 to 2.47E-02. Conclusions An mRSS signature was identified using skin biopsies in SSc patients. Some of these genes (i.e. IRF7, THBS1, COMP or BANK1) have been published using similar approaches in other sets of SSc patients (1), which supports our results. The functional categories of this signature are characteristic for scleroderma pathology reflecting autoimmunity, vasculopathy, inflammation and fibrosis. This mRSS signature needs to be validated in a larger set of SSc patients including assessment of change over time. References Mahoney et al. PLOS Computational Biology 2015: Vol 11; 1–20. Disclosure of Interest I. Agueusop: None declared, S. Illiano: None declared, C. Rocher: None declared, E. Boitier: None declared, J. Murphy: None declared, Y. Allanore Grant/research support from: BMS, Genentech-Roche, Inventiva, Pfizer, sanofi, Consultant for: Actelion, Bayer, Biogen, Genetech-Roche, Galapagos, Medac, Pfizer, Sanofi, Servier, UCB, C. Denton Consultant for: Actelion, Bayer, GSK, CSL Behring, Merck-Serono, Genentech-Roche, Inventiva, Sanofi-Aventis, O. Distler Grant/research support from: Actelion, Bayer, Boehringer Ingelheim, Pfizer, Sanofi, Consultant for: 4 D Science, Actelion, Active Biotec, Bayer, BiogenIdec, BMS, Boehringer Ingelheim, ChemomAb, EpiPharm, espeRare foundation, Genentech/Roche, GSK, Inventiva, Lilly, medac, Mepha, MedImmune, Mitsubishi Tanabe Pharma, Pharmacyclics, Pfizer, Sanofi, Serodapharm, Sinoxa, AbbVie, iQone Healthcare, Mepha, D. Khanna Grant/research support from: Bayer, BMS, Genentech/Roche, Sanofi-Aventis, NIH K24AR063120, Consultant for: Actelion, Bayer, Covis, Cytori, EMD Serono, Genentech/Roche, Gilead, GSK, Sanofi-Aventis, F. Benderitter: None declared

Mating and laying sites of Uromenus brevicollis insularis, a Cyrno-Sardininian micro-endemic species, are described from observations conducted at night in several Corsican localities. Asphodelus ramosus was found to be a key host species as both mating and oviposition of this insect take place mainly on the erect dry stems of the plant. Some aspects of the meeting of the sexes are assessed: male stridulation does not appear to play an important role. The females lay their eggs, creating vertical lines in the stem by chewing regularly spaced holes containing nearly 3 eggs per hole. One to three laying lines can be observed on a single stem. Ferula communis is frequently used as an alternative laying site when A. ramosus is absent or rare, but in this case, the eggs can be attacked by woodpeckers (Dendrocopos sp.) or parasitized by Hymenoptera.; Les sites d'accouplement et de ponte d'Uromenus brevicollis insularis, micro-endémique cyrno-sarde, sont décrits à partir d'observations nocturnes de terrain dans plusieurs localités corses. Asphodelus ramosus est une espèce clé dans la mesure où ses tiges sèches dressées sont le lieu principal de ces deux activités de reproduction. Les modalités de la rencontre des sexes sont décrites et il ne semble pas que la stridulation des mâles joue un rôle prépondérant. Les femelles pondent selon des lignes verticales sur la plante en creusant des trous régulièrement espacés, contenant en moyenne près de trois œufs chacun. On peut rencontrer de une à trois rangées de ponte sur une tige. Nous avons pu observer que les pontes déposées dans Ferula communis, espèce qui semble être particulièrement recherchée en cas d'absence ou faible densité de l'asphodèle, peuvent subir des attaques de pic (Dendrocopos sp.) ou encore d'hyménoptères parasitoïdes, notamment.

International audience; The effect of stocking rate on the species richness, abundance and functional diversity of vascular plants, butterflies and grasshoppers was examined in a semi-natural upland pasture in central France. Over a 5-year period, 3.6-ha plots were continuously grazed by Charolais heifers at 1.4 (High stocking rate), 1.0 (Intermediate) and 0.6 (Low) livestock units (LU) ha(-1). To evaluate botanical diversity, percentage cover of all plant species was estimated in late July in ten fixed 1 m x 1 m quadrats per plot. Butterflies were counted on three occasions between late June and early August along three fixed 50-m-long transects per plot using the 'Pollard walk', with grasshoppers being recorded on two occasions along the same transects. Diversity patterns of the three taxa were affected by stocking rate. For plants, species abundance changed more than species number. Abundance of forbs became higher under the Low compared with the High stocking rate. Stress-tolerant grasses were also more abundant in plots grazed at the Low stocking rate, while an opposite trend was observed for competitive grasses. Butterflies consistently responded to alterations in vegetation composition, especially to the dynamics of nectar plants. The species richness of grasshoppers also increased in plots at the Low stocking rate. The Low and Intermediate stocking rates were suitable for providing a high diversity of the three taxonomic groups. The results suggested that at least butterfly diversity would peak in vegetation taller than that of vascular plants.

Alterations in the energy metabolism of cancer cells have been reported for many years. However, the deleterious mechanisms involved in these deficiencies have not yet been clearly proved. The main goal of this study was to decipher the harmful mechanisms responsible for the respiratory chain deficiencies in the course of diethylnitrosamine (DENA)-induced rat hepatocarcinogenesis, where mitochondrial DNA abnormalities had been previously reported. The respiratory activity of freshly isolated hepatoma mitochondria, assessed by oxygen consumption experiments and enzymatic assays, presented a severe complex I deficiency 19 months after DENA treatment, and later on, in addition, a defective complex III activity. Since respiratory complex subunits are encoded by both nuclear and mitochondrial genes, we checked whether the respiratory chain defects were due to impaired synthesis processes. The specific immunodetection of complex I failed to show any alterations in the steady-state levels of both nuclear and mitochondrial encoded subunits in the hepatomas. Moreover, in vitro protein synthesis experiments carried out on freshly isolated hepatoma mitochondria did not bring to light any modifications in the synthesis of the mitochondrial subunits of the respiratory complexes, whatever the degree of tumor progression. Finally, Southern blot analysis of mitochondrial DNA did not show any major mitochondrial DNA rearrangements in DENA-induced hepatomas. Because the synthetic processes of respiratory complexes did not seem to be implicated in the respiratory chain impairment, these deficiencies could be partly ascribed to a direct toxic impact of highly reactive molecules on these complexes, thus impairing their function. The mitochondrial respiratory chain is an important generator of noxious, reactive oxygen free radicals such as superoxide and H2O2, which are normally catabolized by powerful antioxidant scavengers. Nineteen months after DENA treatment, a general collapse of the antioxidant enzymatic system was demonstrated in the hepatomas, as recurrently observed in cancer cells. This oxidant versus antioxidant imbalance was characterized by the establishment of oxidative stress in the course of hepatocarcinogenesis, as partly shown by the important decrease of glutamine synthetase activity, an enzyme whose function is highly sensitive to oxidant reactions. This disequilibrium would result in a net increase of the steady-state concentration of superoxide generated between respiratory complexes I and III in the mitochondria. Once generated, superoxide would likely inactivate complexes I and III via oxidant reactions on their superoxide-sensitive [4Fe, 4S] clusters. The role of mitochondrial respiratory chain impairment in chemical carcinogenesis and/or the persistence of the cancerous state is further discussed.

L'hexokinase (HK), en catalysant la phosphorylation du glucose, joue un role capital dans le metabolisme de tissus dont le glucose est la source d'energie. Parmi les quatre isoformes connues, HK-IV ou glucokinase est majoritaire dans le foie mais HK-I l'est dans le cerveau, le rein et dans les tumeurs malignes. Elle est libre et cytoplasmique, ou liee et ancree a la mitochondrie, ce qui augmente considerablement son activite enzymatique. On pense qu'il existe un controle de sa fonction fonde sur des changements de conformation entre formes libres et formes liees, ce qui permet de comprendre la cinetique enzymatique de l'HK-I. Cette enzyme constitue un intermediaire essentiel entre le cycle oxydatif et la glycolyse : sa regulation par ancrage porinique constitue un systeme performant d'adaptation aux modifications des apports en oxygene ou en glucose. Dans les tumeurs malignes, la glycolyse est active meme en aerobiose, et l'HK-I mitochondriale contribue a maintenir une activite metabolique intense, meme en hypoxie : cette enzyme pourrait donc se reveler etre une cible therapeutique interessante.