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[Background and Aims] The observed positive diversity effect on ecosystem functioning has rarely been assessed in terms of intraspecific trait variability within populations. Intraspecific phenotypic variability could stem both from underlying genetic diversity and from plasticity in response to environmental cues. The latter might derive from modifications to a plant’s epigenome and potentially last multiple generations in response to previous environmental conditions. We experimentally disentangled the role of genetic diversity and diversity of parental environments on population productivity, resistance against environmental fluctuations and intraspecific phenotypic variation. [Methods} A glasshouse experiment was conducted in which different types of Arabidopsis thaliana populations were established: one population type with differing levels of genetic diversity and another type, genetically identical, but with varying diversity levels of the parental environments (parents grown in the same or different environments). The latter population type was further combined, or not, with experimental demethylation to reduce the potential epigenetic diversity produced by the diversity of parental environments. Furthermore, all populations were each grown under different environmental conditions (control, fertilization and waterlogging). Mortality, productivity and trait variability were measured in each population. [Key Results] Parental environments triggered phenotypic modifications in the offspring, which translated into more functionally diverse populations when offspring from parents grown under different conditions were brought together in mixtures. In general, neither the increase in genetic diversity nor the increase in diversity of parental environments had a remarkable effect on productivity or resistance to environmental fluctuations. However, when the epigenetic variation was reduced via demethylation, mixtures were less productive than monocultures (i.e. negative net diversity effect), caused by the reduction of phenotypic differences between different parental origins. [Conclusions] A diversity of environmental parental origins within a population could ameliorate the negative effect of competition between coexisting individuals by increasing intraspecific phenotypic variation. A diversity of parental environments could thus have comparable effects to genetic diversity. Disentangling the effect of genetic diversity and that of parental environments appears to be an important step in understanding the effect of intraspecific trait variability on coexistence and ecosystem functioning., This work was supported by the Czech Science Foundation (GACR 20-00871S) and the Estonian Research Council (project PSG293 to C.P.C.) and the European Union through the European Regional Development Fund (Centre of Excellence EcolChange to C.P.C.).

International audience; Aim: To compare methods of quantifying serum hepcidin (based on MS and ELISA) and their ability to diagnose true iron deficiency anemia in critically ill patients. Materials & methods: Serum hepcidin was measured in 119 critically ill patients included in the HEPCIDANE clinical trial, using either an ultra-sensitive ELISA kit (from DRG) or two different MS methods. Results: The results show a good correlation between the different methods studied. The Bland–Altman analysis and the Kappa test for clinical groups show a good or very good agreement between the different tests. Conclusion: ELISA or MS show a satisfactory commutability to quantify serum hepcidin. This is of great importance for the determination of therapeutic strategies in iron deficiency.

The Mendelian inheritance pattern of acute intermittent porphyria, hereditary coproporphyria, and variegate porphyria is autosomal dominant, but the clinical phenotype is heterogeneous. Within the general population, penetrance is low, but among first-degree relatives of a symptomatic proband, penetrance is higher. These observations suggest that genetic factors, in addition to mutation of the specific enzyme of the biosynthetic pathway of heme, contribute to the clinical phenotype. Recent studies by others suggested that the genotype of the transporter protein ABCB6 contribute to the porphyria phenotype. Identifying the molecule(s) that are transported by ABCB6 has been problematic and has led to uncertainty with respect to how or if variants/mutants contribute to phenotypic heterogeneity. Knockout mouse models of Abcb6 have not provided a direction for investigation as homozygous knockout animals do not have a discrete phenotype. To address the proposed link between ABC6 genotype and porphyria phenotype, a large cohort of patients with acute hepatic porphyria and erythropoietic protoporphyria was analyzed. Our studies showed that ABCB6 genotype did not correlate with disease severity. Therefore, genotyping of ABCB6 in patients with acute hepatic porphyria and erythropoietic protoporphyria is not warranted.

Premise of research. Root traits of annual plants are known to vary across environmentally manipulated conditions in controlled settings. Roots absorb nutrients and water, essential for individual ...

Functional and phylogenetic diversity (FD and PD respectively) of the resident community are expected to exert a key role in community resistance to colonization by surrounding species, and their establishment success. However, few studies have explored this topic experimentally or evaluated the interactive effects of these diversity measures. We implemented a diversity experiment to disentangle the role of FD and PD by sowing mixtures of 6 species, drawn from a pool of 19 species naturally coexisting in central European mesic meadows. The mixtures were designed to cover four independent combinations of high and low FD and PD. Species covers were estimated in spring and late summer over two growing seasons. We then assessed the establishment success of colonizers as a function of their mean traits and phylogenetic distance to the resident (i.e. sown) communities, as well as the resistance of the resident communities to natural colonizers as a function of their functional and phylogenetic structure. Results generally indicated a temporal shift regarding which trait values made a colonizer successful, from an acquisitive strategy in early stages to a more conservative trait syndrome in later stages. FD decreased community resistance to natural colonization. However, PD tempered this effect: with high PD, FD was not significant, suggesting complementary information between these two components of biodiversity. On average, colonizing species were more functionally distant from the resident species in sown communities with high functional diversity, i.e. those that were more colonized. Synthesis. Our results confirm an interplay between FD and PD during community assembly processes, namely resistance to colonizers, suggesting that these two descriptors of biodiversity only partially overlap in their contribution to the overall ecological structure of a community. The hypothesis that higher FD increases resistance through a more complete use of resources was challenged. Results rather suggested that greater FD could provide an unsaturated functional trait space allowing functionally unique species to occupy it., The study was supported by Czech Science Foundation grant GA16‐15012S. C.P.C. was supported by a Marie Curie Intra‐European Fellowship within the European Commission 7th Framework Programme (TANDEM; project 626392) and the Estonian Research Council (project PSG293). E.V. was funded by the 2017 program for attracting and retaining talent of Comunidad de Madrid (no. 2017‐T2/AMB‐5406).

Factor XI (FXI) has been shown to bind platelets, but the functional significance of this observation remains unknown. Platelets are essential for hemostasis and play a critical role in thrombosis, whereas FXI is not essential for hemostasis but promotes thrombosis. An apparent functional contradiction, platelets are known to support thrombin generation, yet platelet granules release protease inhibitors, including those of activated FXI (FXIa). We aim to investigate the secretory and binding mechanisms by which platelets could support or inhibit FXIa activity. The presence of platelets enhanced FXIa activity in a purified system and increased coagulation Factor IX (FIX) activation by FXIa and fibrin generation in human plasma. In contrast, platelets reduced the activation of FXI by activated coagulation factor XII (FXIIa) and the activation of FXII by kallikrein (PKa). Incubation of FXIa with the platelet secretome, which contains FXIa inhibitors, such as protease nexin-II, abolished FXIa activity, yet in the presence of activated platelets, the secretome was not able to block the activity of FXIa. FXIa variants lacking the anion-binding sites did not alter the effect of platelets on FXIa activity or interaction. Western blot analysis of bound FXIa [by FXIa-platelet membrane immunoprecipitation] showed that the interaction with platelets is zinc dependent and, unlike FXI binding to platelets, not dependent on glycoprotein Ib. FXIa binding to the platelet membrane increases its capacity to activate FIX in plasma likely by protecting it from inhibition by inhibitors secreted by activated platelets. Our findings suggest that an interaction of FXIa with the platelet surface may induce an allosteric modulation of FXIa.

The leaves and petioles of Paulownia elongata x fortunei are residual fractions from the tree plantations commercially destined to the production of wood and their valorization could contribute to the rational utilization of this resource. The saccharidic fraction is the most abundant in both parts of the plant and the sugar profile is very similar, but the ethanol extractives are more abundant in leaves. Non isothermal processing was selected since it provided better results than isothermal extraction with shorter times. For this reason, optimization of autohydrolysis under non isothermal operation (140–240 °C) was performed for both materials: leaves and petioles. The final autohydrolysis temperature highly influenced the saccharidic, proteic, phenolic and volatile composition of the extracts. Operating under selected conditions leaves provided extracts with more antioxidant compounds than petioles. The proposed technology provides a variety of commercially valuable components, which could contribute to the integral use of this energetic crop following a biorefinery approach.

INTRODUCTION: Vascular devices such as stents, hemodialyzers, and membrane oxygenators can activate blood coagulation and often require the use of systemic anticoagulants to selectively prevent intravascular thrombotic/embolic events or extracorporeal device failure. Coagulation factor (F)XII of the contact activation system has been shown to play an important role in initiating vascular device surface-initiated thrombus formation. As FXII is dispensable for hemostasis, targeting the contact activation system holds promise as a significantly safer strategy than traditional antithrombotics for preventing vascular device-associated thrombosis. OBJECTIVE: Generate and characterize anti-FXII monoclonal antibodies that inhibit FXII activation or activity. METHODS: Monoclonal antibodies against FXII were generated in FXII-deficient mice and evaluated for their binding and anticoagulant properties in purified and plasma systems, in whole blood flow-based assays, and in an in vivo non-human primate model of vascular device-initiated thrombus formation. RESULTS: A FXII antibody screen identified over 400 candidates, which were evaluated in binding studies and clotting assays. One non-inhibitor and six inhibitor antibodies were selected for characterization in functional assays. The most potent inhibitory antibody, 1B2, was found to prolong clotting times, inhibit fibrin generation on collagen under shear, and inhibit platelet deposition and fibrin formation in an extracorporeal membrane oxygenator deployed in a non-human primate. CONCLUSION: Selective contact activation inhibitors hold potential as useful tools for research applications as well as safe and effective inhibitors of vascular device-related thrombosis.

PURPOSE-: Crosslinked poly(vinyl alcohol) (PVA) is a biomaterial that can be used for multiple cardiovascular applications. The success of implanted biomaterials is contingent on the properties of the material. A crucial consideration for blood-contacting devices is their potential to incite thrombus formation, which is dependent on the material surface properties. The goal of this study was to quantify the effect of different crosslinking methods of PVA hydrogels on in vitro thrombogenicity. METHODS-: PVA was manufactured using three different crosslinking methods: 30% sodium trimetaphosphate (STMP), three 24hr freeze-thaw cycles (FT), and 2% glutaraldehyde-crosslinked (GA) to produce STMP-PVA, FT-PVA and GA-PVA, respectively. Expanded polytetrafluoroethylene (ePTFE) was used as a clinical control. As markers of thrombus formation, the degree of coagulation factor (F) XII activation, fibrin formation, and platelet adhesion were measured. RESULTS-: The GA-PVA material increased FXII activation in the presence of cofactors compared to vehicle and increase platelet adhesion compared to other PVA surfaces. The STMP-PVA and FT-PVA materials had equivalent degrees of FXII activation, fibrin formation and platelet adhesion. CONCLUSION-: This work supports crosslinker dependent thrombogenicity of PVA hydrogels and advances our understanding of how the manufacturing of a PVA hydrogel affects its hemocompatibility.

Background The contact factor XII (FXII) activates upon contact with a variety of charged surfaces. Activated FXII (FXIIa) activates factor XI, which activates factor IX, resulting in thrombin generation, platelet activation, and fibrin formation. In both in vitro and in vivo rabbit models, components of medical devices, including extracorporeal oxygenators, are known to incite fibrin formation in a FXII‐dependent manner. Since FXII has no known role in hemostasis and its inhibition is therefore likely a safe antithrombotic approach, we investigated whether FXII inhibition also reduces accumulation of platelets in extracorporeal oxygenators. Objectives We aimed to determine the effect of FXII inhibition on platelet deposition in perfused extracorporeal membrane oxygenators in nonhuman primates. Methods A potent FXII neutralizing monoclonal antibody, 5C12, was administered intravenously to block contact activation in baboons. Extracorporeal membrane oxygenators were temporarily deployed into chronic arteriovenous access shunts. Radiolabeled platelet deposition in oxygenators was quantified in real time using gamma camera imaging. Biochemical assays were performed to characterize the method of action of 5C12. Results The anti‐FXII monoclonal antibody 5C12 recognized both the alpha and beta forms of human and baboon FXII by binding to the protease‐containing domain, and inhibited FXIIa activity. Administration of 5C12 to baboons reduced platelet deposition and fibrin formation in the extracorporeal membrane oxygenators, in both the presence and absence of systemic low‐dose unfractionated heparin. The antiplatelet dose of 5C12 did not cause measurable increases in template bleeding times in baboons. Conclusions FXII represents a possible therapeutic and safe target for reducing platelet deposition and fibrin formation during medical interventions including extracorporeal membrane oxygenation.

Phenotypic plasticity is essential for organisms to adapt to local ecological conditions. It is expected that mutualistic interactions, such as arbuscular mycorrhizal (AM) symbiosis, mediate plant phenotypic plasticity, although it is not clear to what extent this plasticity may be heritable (i.e. transgenerational plasticity). We tested for plant plasticity within- and across-generations in response to AM symbiosis and varying water availability in a full factorial experiment over two generations, using a genetically uniform line of a perennial apomictic herb, Taraxacum brevicorniculatum. We examined changes in phenotype, performance and AM fungal colonization of the offspring throughout plant development. AM symbiosis and water availability triggered phenotypic changes during the life cycle of plants. Additionally, both factors triggered adaptive transgenerational effects especially detectable during the juvenile stage of the offspring. Water deficit and absence of AM fungi caused concordant plant phenotypic modifications towards a ‘stress-coping phenotype’, both within and across generations. Parental environment also affected AM fungal colonization of the offspring. Juvenile offspring of amply watered parents and adut offspring of mycorrhizal parents had increasing length of root colonized by AM fungi when they were under water stress. Synthesis. We show that, in addition to providing beneficial transgenerational effects in offspring traits proxies of fitness (such as increased biomass, survival or nutritional status), AM symbiosis can trigger transgenerational plasticity in anatomical and physiological traits related to resource-use acquisition, and further influence offspring AM fungal colonization. Our results show that AM symbiosis could improve plants' ability to cope with environmental stress, not only within, but also across generations., This research was financially supported by the Czech Science Foundation grant GACR (Grant No. GA17-11281S) and the European Union through the European Regional Development Fund (Dora Plus grant). J.P. was funded by the Irish Research Council Laureate Awards 2017/2018 (IRCLA/2017/60) to Yvonne Buckley. I.H., M.Ö., C.P.C. and M.M. received support by grants from the Estonian Research Council (PSG293, PUT1170, PRG1065) and by the European Regional Development Fund (Centre of Excellence EcolChange)

Erythropoietic porphyrias are caused by enzymatic dysfunctions in the heme biosynthetic pathway, resulting in porphyrins accumulation in red blood cells. The porphyrins deposition in tissues, including the skin, leads to photosensitivity that is present in all erythropoietic porphyrias. In the bone marrow, heme synthesis is mainly controlled by intracellular labile iron by post-transcriptional regulation: translation of ALAS2 mRNA, the first and rate-limiting enzyme of the pathway, is inhibited when iron availability is low. Moreover, it has been shown that the expression of ferrochelatase (FECH, an iron-sulfur cluster enzyme that inserts iron into protoporphyrin IX to form heme), is regulated by intracellular iron level. Accordingly, there is accumulating evidence that iron status can mitigate disease expression in patients with erythropoietic porphyrias. This article will review the available clinical data on how iron status can modify the symptoms of erythropoietic porphyrias. We will then review the modulation of heme biosynthesis pathway by iron availability in the erythron and its role in erythropoietic porphyrias physiopathology. Finally, we will summarize what is known of FECH interactions with other proteins involved in iron metabolism in the mitochondria.

An accumulating body of evidence indicates that natural plant populations harbour a large diversity of transposable elements (TEs). TEs provide genetic and epigenetic variation that can substantially translate into changes in plant phenotypes. Despite the wealth of data on the ecological and evolutionary effects of TEs on plant individuals, we have virtually no information on the role of TEs on populations and ecosystem functioning. On the example of Arabidopsis thaliana, we demonstrate that TE-generated variation creates differentiation in ecologically important functional traits. In particular, we show that Arabidopsis populations with increasing diversity of individuals differing in copy numbers of the ONSEN retrotransposon had higher phenotypic and functional diversity. Moreover, increased diversity enhanced population productivity and reduced performance of interspecific competitors. We conclude that TE-generated diversity can have similar effects on ecosystem as usually documented for other biological diversity effects.

Iron is essential to key biological processes of all living organisms. Proper iron levels must be maintained to meet biological needs and prevent toxicity. Given the central role played by the hormone hepcidin in systemic iron homeostasis, extensive research has sought to identify regulators of its expression. Diverse evidence shows the gut to be an essential sensor and regulator of iron homeostasis, independently of other known hepcidin regulators, including bone marrow signals. Here we identify gut-derived serotonin as a key physiological factor in hepcidin regulation. In response to hypoxia, serotonin synthesized and secreted by enterochromaffin cells can act beyond the gut to repress hepcidin expression in the liver, through a 5-HT2Breceptor-dependent pathway. Bone marrow transplant experiments clearly indicate the gut is responsible for hepcidin repression. This regulatory system appears to be conserved in humans: a significant negative correlation exists between hepcidin and serotonin levels in the serum of healthy individuals. Our findings imply hepcidin regulation by serotonin is a physiological process, and modulation of the gut serotonergic system may have broad therapeutic implications.

International audience; Duchenne muscular dystrophy (DMD) is an X-linked disease caused by mutations in the dystrophin gene leading to the absence of the normal dystrophin protein. The efforts of many laboratories brought new treatments of DMD to the reality, but ongoing and forthcoming clinical trials suffer from absence of valuable biomarkers permitting to follow the outcome of the treatment day by day and to adjust the treatment if needed. In the present study the levels of 128 urinary proteins including growth factors, cytokines and chemokines were compared in urine of DMD patients and age related control subjects by antibody array approach. Surprisingly, statistically significant difference was observed only for urinary ferritin whose level was 50 times higher in young DMD patients. To explain the observed high urinary ferritin content we analysed the levels of iron, iron containing proteins and proteins involved in regulation of iron metabolism in serum and urine of DMD patients and their age-matched healthy controls. Obtained data strongly suggest that elevated level of urinary ferritin is functionally linked to the renal management of myoglobin iron derived from leaky muscles of DMD patients. This first observation of the high level of ferritin in urine of DMD patients permits to consider this protein as a new urinary biomarker in muscular dystrophies and sheds light on the mechanisms of iron metabolism and kidney functioning in DMD.

Iron deficiency with or without anemia, needing continuous iron supplementation, is very common in obese patients, particularly those requiring bariatric surgery. The aim of this study was to address the impact of weight loss on the rescue of iron balance in patients who underwent sleeve gastrectomy (SG), a procedure that preserves the duodenum, the main site of iron absorption. The cohort included 88 obese women, sampling of blood and duodenal biopsies of 35 patients were performed before and one year after SG. An analysis of the 35 patients consisted in evaluating iron homeostasis including hepcidin, markers of erythroid iron deficiency (soluble transferrin receptor (sTfR) and erythrocyte protoporphyrin (PPIX)), expression of duodenal iron transporters (DMT1 and ferroportin) and inflammatory markers. After surgery, sTfR and PPIX were decreased. Serum hepcidin levels were increased despite the significant reduction in inflammation. DMT1 abundance was negatively correlated with higher level of serum hepcidin. Ferroportin abundance was not modified. This study shed a new light in effective iron recovery pathways after SG involving suppression of inflammation, improvement of iron absorption, iron supply and efficiency of erythropoiesis, and finally beneficial control of iron homeostasis by hepcidin. Thus, recommendations for iron supplementation of patients after SG should take into account these new parameters of iron status assessment.

The crosstalk between the transformed tumoral cells and their microenvironment is a key aspect for pancreatic ductal adenocarcinoma (PDAC) progression. This molecular dialog is intensively studied because it may result in an efficient therapeutic target. Contrary to this near microenvironment, the stromal portion in direct contact with the transformed cells, a far microenvironment, placed at the periphery of the tumor mass, produces factors signaling tumors. Among these factors, REG3β, produced by this part of the pancreas, is an important factor in promoting tumor progression. This paper demonstrated that targeting REG3β protein with specific antibodies limits the PDAC tumor growth in an orthotopic, syngeneic mice model induced by injection of Panc02 cells. Then, we showed that CTGF is over-expressed in response to REG3β in PDAC-derived cells. Moreover, inactivation of REG3β by treating tumors with anti-REG3β antibodies results in a strong decrease of CTGF in PDAC tumors. Lastly, we demonstrated that forced expression of CTGF in xenografted Panc02 cells abolishes the therapeutic effect of the anti-REG3β antibody treatment. Altogether, these results indicate that the effect of REG3β in promoting PDAC progression is mediated by CTGF over-activation. Thus, REG3β is a promising therapeutic target to treat PDAC with an original rationale. In conclusion, we demonstrated that the far microenvironment is essential for PDAC progression by producing active secretory factors, and some of them could be used as therapeutic targets., This work was supported by La Ligue Contre le Cancer, INCa, Canceropole PACA, and INSERM.

Erythropoietic protoporphyria (EPP), the most common porphyria of childhood and the third most common porphyria of adulthood, is characterized clinically by painful, non-blistering cutaneous photosensitivity. Two distinct inheritance patterns involving mutations affecting genes that encode enzymes of the heme biosynthetic pathway underlie the clinical phenotype. Aminolevulinic acid synthase 2 (ALAS2), the rate limiting enzyme of the heme pathway in the erythron, is a therapeutic target in EPP because inhibiting enzyme function would reduce downstream production of protoporphyrin IX (PPIX), preventing accumulation of the toxic molecule and thereby ameliorating symptoms. Isoniazid (INH) is widely used for treatment of latent and active M. tuberculosis (TB). Sideroblastic anemia is observed in some patients taking INH, and studies have shown that this process is a consequence of inhibition of ALAS2 by INH. Based on these observations, we postulated that INH might have therapeutic activity in patients with EPP. We challenged this hypothesis in a murine model of EPP and showed that, after 4 weeks of treatment with INH, both plasma PPIX and hepatic PPIX were significantly reduced. Next, we tested the effect of INH on patients with EPP. After eight weeks, no significant difference in plasma or red cell PPIX was observed among the 15 patients enrolled in the study. These results demonstrate that while INH can lower PPIX in an animal model of EPP, the standard dose used to treat TB is insufficient to affect levels in humans.

Objective— Activation of coagulation FXI (factor XI) by FXIIa (activated factor XII) is a prothrombotic process. The endothelium is known to play an antithrombotic role by limiting thrombin generation and platelet activation. It is unknown whether the antithrombotic role of the endothelium includes sequestration of FXIa (activated factor XI) activity. This study aims to determine the role of endothelial cells (ECs) in the regulation of the intrinsic pathway of coagulation. Approach and Results— Using a chromogenic assay, we observed that human umbilical veins ECs selectively blocked FXIa yet supported kallikrein and FXIIa activity. Western blotting and mass spectrometry analyses revealed that FXIa formed a complex with endothelial PAI-1 (plasminogen activator inhibitor-1). Blocking endothelial PAI-1 increased the cleavage of a chromogenic substrate by FXIa and the capacity of FXIa to promote fibrin formation in plasma. Western blot and immunofluorescence analyses showed that FXIa–PAI-1 complexes were either released into the media or trafficked to the early and late endosomes and lysosomes of ECs. When baboons were challenged with Staphylococcus aureus to induce a prothrombotic phenotype, an increase in circulating FXIa–PAI-1 complex levels was detected by ELISA within 2 to 8 hours postchallenge. Conclusions— PAI-1 forms a complex with FXIa on ECs, blocking its activity and inducing the clearance and degradation of FXIa. Circulating FXIa–PAI-1 complexes were detected in a baboon model of S. aureus sepsis. Although ECs support kallikrein and FXIIa activity, inhibition of FXIa by ECs may promote the clearance of intravascular FXIa. Visual Overview— An online visual overview is available for this article.

Erythropoietic protoporphyria (EPP) is a hereditary disease characterized by a deficiency in ferrochelatase (FECH) activity. FECH activity is responsible for the accumulation of protoporphyrin IX (PPIX). Without etiopathogenic treatment, EPP manifests as severe photosensitivity. 95% of affected individuals present a hypomorphic FECH allele trans to a loss-of-function (LOF) FECH mutation, resulting in a reduction in FECH activity in erythroblasts below a critical threshold. The hypomorphic allele promotes the use of a cryptic acceptor splice site, generating an aberrant FECH mRNA, which is responsible for the reduced level of wild-type FECH mRNA and, ultimately, FECH activity. We have previously identified an antisense oligonucleotide (AON), AON-V1 (V1), that redirects splicing to the physiological acceptor site and reduces the accumulation of PPIX. Here, we developed a specific strategy that uses transferrin receptor 1 (TRF1) as a Trojan horse to deliver V1 to erythroid progenitors. We designed a bifunctional peptide (P(1)-9R) including a TFR1-targeting peptide coupled to a nine-arginine cell-penetrating peptide (CPP) that facilitates the release of the AON from TFR1 in endosomal vesicles. We demonstrated that the P(1)-9R/V1 nanocomplex promotes the efficient and prolonged redirection of splicing towards the physiological splice site and subsequent normalization of WT FECH mRNA and protein levels. Finally, the P(1)-9R/V1 nanocomplex increases WT FECH mRNA production and significantly decreases PPIX accumulation in primary cultures of differentiating erythroid progenitors from an overt EPP-affected individual. P(1)-9R is a method designed to target erythroid progenitors and represents a potentially powerful tool for the in vivo delivery of therapeutic DNA in many erythroid disorders.

Competitive exclusion is to be expected between phylogenetically similar species that share traits and resources. However, species may overcome this, either through differentiation of their responses to biotic and abiotic conditions, or by trait differentiation, thus enabling their coexistence. We identified differences in phenotypic traits between seven coexisting Carex species and their responses to competition and fertilization in pot experiments, before using long-term field experiments to generate responses of the Carex species to fertilization and mowing and to illustrate temporal variability between species. Finally, we assessed how effective the results of the pot experiment were at predicting species responses in the field. In pot experiments, we found that species responded more to competition than to fertilization. Notably, all species showed similar responses to these factors in the pot experiments. Fertilization decreased the root:shoot ratio, whilst competition decreased growth-related characteristics such as total biomass, irrespective of the species. Differences among species were only found in their clonal response to competition, namely rhizome production and generation rate of new ramets. These findings support the idea that different clonal growth strategies may facilitate niche partitioning of Carex species. Species responses measured from pot experiments were poor predictors of their responses in the field experiment. Nevertheless, we confirmed the prediction that, over time, Carex species with lower growth rates in pot experiments showed more stable biomass production than in the field. We suggest that differences in clonal traits and temporal dynamics support the ability of Carex species to avoid competitive exclusion, enabling their coexistence., The research was supported by the grant from the Czech Science Foundation GAČR 20-13637S. Erasmus + program provided financial support to Keily Tammaru, Karola Anna Barta, Emilia Innocenti Degli, Szilvia Márta Neumann and Hayden Wagia during their stay in Czech Republic. University of Ferrara in Italy provided financial support for Emilia Innocenti Degli. Tempus Public Foundation in Hungary provided financial support for Amira Fatime Abbas, Réka Kiss and Katalin Lukács. Réka Kiss and Katalin Lukács was supported by the NKFI FK 124404 grant of the National Research, Development and Innovation Office, Hungary.

Aim(s) Because of their prothrombotic and neuroinflammatory effects, neutrophils and neutrophil extracellular traps (NETs) represent interesting therapeutic targets for spontaneous intracerebral haemorrhage (sICH). We investigated the presence, spatial and temporal distribution of NETs in a human sICH post-mortem study. Methods From 2005 to 2019, all sICH patients who came to autopsy within the first month after stroke were included and grouped according to the timing of death: 72 hours, 4-7 days, 8-15 days and > 15 days after ICH onset. Paraffin-embedded tissue was extracted from four strategic areas: haematoma, peri-haematomal area, ipsilateral surrounding brain tissue and a control contralateral area. Myeloperoxidase and histone H3 citrulline were immunolabelled to detect neutrophils and NETs, respectively. Results Neutrophils were present in the brains of the 14 cases (4 men, median age: 78 years) and NETs were found in 7/14 cases. Both neutrophils and NETs were detected within the haematoma but also in the surrounding tissue. The appearance of neutrophils and NETs was time-dependent, following a two-wave pattern: during the first 72 hours and between 8-15 days after ICH onset. Qualitative examination showed that neutrophils and NETs were mainly located around dense fibrin fibres within the haematoma. Conclusions These observations provide evidence for NETs infiltration in the brain of patients who die from sICH. NETs might interact with early haemostasis within the haematoma core, and with the surrounding neuroinflammatory response. These findings open research perspectives for NETs in the treatment of sICH injuries.

International audience; Introduction: Givosiran is an RNA interference therapeutic designed to block the synthesis of the aminolevulinic acid (ALA) synthase 1 (ALAS1) enzyme in patients with acute intermittent porphyria (AIP). Givosiran may have adverse effects on the kidney.Methods: We performed a descriptive case series of renal function parameters of all the patients who received givosiran in France. Twenty patients receiving givosiran between March 2018 and July 2020 in France were analyzed: 7 patients in the ENVISION trial and 13 patients treated in collaboration with the Centre de Référence Maladies Rares Prophyries.Results: A transient decrease in renal function was observed in all but 2 patients (90%) within the 3 months following givosiran initiation. None of the patients developed acute kidney injury or disease. Patients of the ENVISION cohort were followed for at least 30 months: 2 patients did not experience estimated glomerular filtration rate (eGFR) loss, 3 patients experienced a modest decline in renal function (–3.4 ml/min per 1.73 m2 per year in average), and 2 patients had a clearly abnormal eGFR loss (–5.8 ml/min per 1.73 m2 per year in average). None of the patients had biochemical signs of active tubular or glomerular injury. One patient’s kidney was biopsied without finding any signs of an active kidney disease and with normal ALAS1 tubular expression.Conclusions: Givosiran is associated with a transient moderate increase in serum creatinine (sCr) without sign of kidney injury. A long-term deleterious impact of ALAS1 inhibition on renal function is not excluded. Because AIP promotes chronic kidney disease, it is difficult to separate the long-term effects of givosiran from the natural progression of the renal disease.

Polyethylene glycols (PEGs) are neutral polymers widely used in biomedical applications due to its hydrophilicity and biocompatibility. Exosomes are small vesicles secreted by nearly all cell types and play an important role in normal and pathological conditions. The purpose of this study was to evaluate the role of a 35-kDa molecular weight PEG (PEG35) on the modulation of exosome-mediated inflammation. Human macrophage-like cells THP-1, epithelial BICR-18, and CAPAN-2 cells were exposed to PEG35 prior to incubation with exosomes of different cellular origins. Exosome internalization was evaluated by confocal microscopy and flow cytometry. In another set of experiments, macrophages were treated with increasing concentrations of PEG35 prior to exposure with the appropriate stimuli: lipopolysaccharide, BICR-18-derived exosomes, or exosomes from acute pancreatitis-induced rats. Nuclear Factor Kappa B (NF&kappa, B) and Signal transducer and activator of transcription 3 (STAT3) activation and the expression levels of pro-inflammatory Interleukin 1&beta, (IL1&beta, ) were determined. PEG35 administration significantly enhanced the internalization of exosomes in both macrophages and epithelial cells. Further, PEG35 ameliorated the inflammatory response induced by acute pancreatitis-derived exosomes by reducing the expression of IL1&beta, and p65 nuclear translocation. Our results revealed that PEG35 promotes the cellular uptake of exosomes and modulates the pro-inflammatory effect of acute pancreatitis-derived vesicles through inhibition of NF&kappa, B, thus emphasizing the potential value of PEG35 as an anti-inflammatory agent for biomedical purposes.

Aldehyde dehydrogenase 2 (ALDH2) is best known for its critical detoxifying role in liver alcohol metabolism. However, ALDH2 dysfunction is also involved in a wide range of human pathophysiological situations and is associated with complications such as cardiovascular diseases, diabetes mellitus, neurodegenerative diseases and aging. A growing body of research has shown that ALDH2 provides important protection against oxidative stress and the subsequent loading of toxic aldehydes such as 4-hydroxy-2-nonenal and adducts that occur in human diseases, including ischemia reperfusion injury (IRI). There is increasing evidence of its role in IRI pathophysiology in organs such as heart, brain, small intestine and kidney; however, surprisingly few studies have been carried out in the liver, where ALDH2 is found in abundance. This study reviews the role of ALDH2 in modulating the pathways involved in the pathophysiology of IRI associated with oxidative stress, autophagy and apoptosis. Special emphasis is placed on the role of ALDH2 in different organs, on therapeutic “preconditioning” strategies, and on the use of ALDH2 agonists such as Alda-1, which may become a useful therapeutic tool for preventing the deleterious effects of IRI in organ transplantation., This work was supported by Instituto de Salud Carlos III through FIS project PI 15/00110 co-funded by FEDER from Regional Development European Funds (European Union) and the FOIE GRAS project, which has received funding from the European Union’s Horizon 2020 Research and Innovation programme under the Marie Sklodowska-Curie Grant (Agreement No. 722619).

Congenital erythropoietic porphyria (CEP) is an inborn error of heme synthesis resulting from uroporphyrinogen III synthase (UROS) deficiency and the accumulation of nonphysiological porphyrin isomer I metabolites. Clinical features are heterogeneous among patients with CEP but usually combine skin photosensitivity and chronic hemolytic anemia, the severity of which is related to porphyrin overload. Therapeutic options include symptomatic strategies only and are unsatisfactory. One promising approach to treating CEP is to reduce the erythroid production of porphyrins through substrate reduction therapy by inhibiting 5-aminolevulinate synthase 2 (ALAS2), the first and rate-limiting enzyme in the heme biosynthetic pathway. We efficiently reduced porphyrin accumulation after RNA interference–mediated downregulation of ALAS2 in human erythroid cellular models of CEP disease. Taking advantage of the physiological iron-dependent posttranscriptional regulation of ALAS2, we evaluated whether iron chelation with deferiprone could decrease ALAS2 expression and subsequent porphyrin production in vitro and in vivo in a CEP murine model. Treatment with deferiprone of UROS-deficient erythroid cell lines and peripheral blood CD34+-derived erythroid cultures from a patient with CEP inhibited iron-dependent protein ALAS2 and iron-responsive element–binding protein 2 expression and reduced porphyrin production. Furthermore, porphyrin accumulation progressively decreased in red blood cells and urine, and skin photosensitivity in CEP mice treated with deferiprone (1 or 3 mg/mL in drinking water) for 26 weeks was reversed. Hemolysis and iron overload improved upon iron chelation with full correction of anemia in CEP mice treated at the highest dose of deferiprone. Our findings highlight, in both mouse and human models, the therapeutic potential of iron restriction to modulate the phenotype in CEP.

Phenotypic plasticity is essential for organisms to adapt to local ecological conditions. It is expected that mutualistic interactions, such as arbuscular mycorrhizal (AM) symbiosis, mediate plant phenotypic plasticity, although it is not clear to what extent this plasticity may be heritable (i.e., transgenerational plasticity).We tested for plant plasticity within- and across-generations in response to AM symbiosis and varying water availability in a full factorial experiment over two generations, using a genetically uniform line of a perennial apomictic herb, Taraxacum brevicorniculatum. We examined changes in phenotype, performance, and AM fungal colonization of the offspring throughout plant development.AM symbiosis and water availability triggered phenotypic changes during the life cycle of plants. Additionally, both triggered adaptive transgenerational effects, especially detectable during the juvenile stage of the offspring. Water deficit and absence of AM fungi caused concordant plant phenotypic modifications towards a “stress-coping phenotype”, both within- and across-generations. AM fungal colonization of offspring was also affected by the parental environment.AM symbiosis can trigger within-generation and transgenerational plasticity in terms of functional traits related to resource-use acquisition and AM fungal colonization. Thus, transgenerational effects of mycorrhizal symbiosis are not limited to plant fitness, but also improve plants’ ability to cope with environmental stress.

Acute pancreatitis is an inflammatory disorder of the pancreas. Its presentation ranges from self-limiting disease to acute necrotizing pancreatitis (ANP) with multiorgan failure and a high mortality. Polyethylene glycols (PEGs) are non-immunogenic, non-toxic, and water-soluble chemicals composed of repeating units of ethylene glycol. The present article explores the effect of PEG35 administration on reducing the severity of ANP and associated lung injury. ANP was induced by injection of 5% sodium taurocholate into the biliopancreatic duct. PEG35 was administered intravenously either prophylactically or therapeutically. Three hours after ANP induction, pancreas and lung tissue samples and blood were collected and ANP severity was assessed. To evaluate the inflammatory response, gene expression of pro-inflammatory cytokines and chemokine and the changes in the presence of myeloperoxidase and adhesion molecule levels were determined in both the pancreas and the lung. To evaluate cell death, lactate dehydrogenase (LDH) activity and apoptotic cleaved caspase-3 localization were determined in plasma and in both the pancreatic and lung tissue respectively. ANP-associated local and systemic inflammatory processes were reduced when PEG35 was administered prophylactically. PEG35 pre-treatment also protected against acute pancreatitis-associated cell death. Notably, the therapeutic administration of PEG35 significantly decreased associated lung injury, even when the pancreatic lesion was equivalent to that in the untreated ANP-induced group. Our results support a protective role of PEG35 against the ANP-associated inflammatory process and identify PEG35 as a promising tool for the treatment of the potentially lethal complications of the disease, This study was funded by Instituto de Salud Carlos III (ISCIII) through the FIS project PI13/01224 to Emma Folch-Puy (Co-funded by European Regional Development Fund/European Social Fund).

The aim of the UniProt Knowledgebase is to provide users with a comprehensive, high-quality and freely accessible set of protein sequences annotated with functional information. In this article, we describe significant updates that we have made over the last two years to the resource. The number of sequences in UniProtKB has risen to approximately 190 million, despite continued work to reduce sequence redundancy at the proteome level. We have adopted new methods of assessing proteome completeness and quality. We continue to extract detailed annotations from the literature to add to reviewed entries and supplement these in unreviewed entries with annotations provided by automated systems such as the newly implemented Association-Rule-Based Annotator (ARBA). We have developed a credit-based publication submission interface to allow the community to contribute publications and annotations to UniProt entries. We describe how UniProtKB responded to the COVID-19 pandemic through expert curation of relevant entries that were rapidly made available to the research community through a dedicated portal. UniProt resources are available under a CC-BY (4.0) license via the web at https://www.uniprot.org/.

Antecedentes y Objetivos: La diversidad de macrolíquenes saxícolas en el estado de Guanajuato es poco conocida. Los escasos datos que existen son menciones de colectas y de especies en páginas electrónicas especializadas. El objetivo de este trabajo fue contribuir, mediante la elaboración de un listado florístico, al conocimiento de la diversidad de macrolíquenes saxícolas en cuatro localidades (cerro “La Bufa”, parque ecológico “El Orito”, carretera panorámica “El Pípila” y Sierra de Santa Rosa de Lima).Métodos: Los ejemplares fueron recolectados y posteriormente determinados mediante el uso de claves especializadas, considerando características morfológicas, anatómicas y químicas. Se apoyó en observaciones al microscopio estereoscópico y compuesto, respuesta a reactivos químicos y, en algunos casos, en la realización de cromatografía de capa fina. Finalmente se revisaron descripciones de las mismas y se cotejaron los ejemplares determinados con aquellos existentes en el herbario EBUM de la Universidad Michoacana de San Nicolás de Hidalgo.Resultados clave: Se presenta una lista de 42 especies para el distrito minero de Guanajuato, que constituyen registros nuevos para las localidades estudiadas; 23 son nuevos registros para el estado de Guanajuato y uno lo es para México.Conclusiones: De las 42 especies, la familia Parmeliaceae es la más representativa del área de estudio, especialmente el género Xanthoparmeliacon nueve especies, de las cuales tres son nuevos registros para el estado de Guanajuato y una de ellas lo es para México. La zona de La Bufa con clima semicálido y la ignimbrita como roca dominante reúne la mayoría de las especies registradas. Las especies de las familias Cladoniaceae, Usneaceae, Ramalinaceae y Stereocaulaceae son representativas de la zona de Santa Rosa de Lima en donde domina un clima húmedo y la toba riolítica como roca principal.

Heme plays a critical role in catalyzing life-essential redox reactions in all cells, and its synthesis must be tightly balanced with cellular requirements. Heme synthesis in eukaryotes is tightly regulated by the mitochondrial AAA+ unfoldase CLPX (caseinolytic mitochondrial matrix peptidase chaperone subunit X), which promotes heme synthesis by activation of δ-aminolevulinate synthase (ALAS/Hem1) in yeast and regulates turnover of ALAS1 in human cells. However, the specific mechanisms by which CLPX regulates heme synthesis are unclear. In this study, we interrogated the mechanisms by which CLPX regulates heme synthesis in erythroid cells. Quantitation of enzyme activity and protein degradation showed that ALAS2 stability and activity were both increased in the absence of CLPX, suggesting that CLPX primarily regulates ALAS2 by control of its turnover, rather than its activation. However, we also showed that CLPX is required for PPOX (protoporphyrinogen IX oxidase) activity and maintenance of FECH (ferrochelatase) levels, which are the terminal enzymes in heme synthesis, likely accounting for the heme deficiency and porphyrin accumulation observed in Clpx−/− cells. Lastly, CLPX is required for iron utilization for hemoglobin synthesis during erythroid differentiation. Collectively, our data show that the role of CLPX in yeast ALAS/Hem1 activation is not conserved in vertebrates as vertebrates rely on CLPX to regulate ALAS turnover as well as PPOX and FECH activity. Our studies reveal that CLPX mutations may cause anemia and porphyria via dysregulation of ALAS, FECH, and PPOX activities, as well as of iron metabolism.

Questo articolo è una partnership di ricercatori nel accademico Lega Para Oncologia – LAOPA, il vostro obiettivo è quello di fornire una breve esplorazione sulla parte superiore di articoli scientifici e pubblicazioni tra gli anni 2010 e 2017, gli aspetti generali del cancro seno in una luce contemporanea. La giustificazione è la necessità di affrontare le questioni relative al cancro, in questo caso il cancro al seno, chiede il riconoscimento di eventuali notizie sul tema, dal momento che anche con tutte le quote per il trattamento efficace rimane ancora una malattia con aumentando i livelli di ogni anno. In conclusione, si osserva che rivisitare questo tema è fondamentale non solo per accademici e professionisti, ma anche per la comunità in generale, al fine di servire come strumento di consapevolezza, e le azioni intraprese.

International audience; The cytosolic 5'-nucleotidase cN-II is a highly conserved enzyme implicated in nucleotide metabolism. Based on recent observations suggesting additional roles not directly associated to its enzymatic activity, we studied human cancer cell models with basal or decreased cN-II expression. We developed cancer cells with stable inhibition of cN-II expression by transfection of shRNA-coding plasmids, and studied their biology. We show that human breast cancer cells MDA-MB-231 with decreased cN-II expression better adapt to the disappearance of glucose in growth medium under normoxic conditions than cells with a baseline expression level. This is associated with enhanced in vivo growth and a lower content of ROS in cells cultivated in absence of glucose due to more efficient mechanisms of elimination of ROS. Conversely, cells with low cN-II expression are more sensitive to glucose deprivation in hypoxic conditions. Overall, our results show that cN-II regulates the cellular response to glucose deprivation through a mechanism related to ROS metabolism and defence.

Activated protein C (APC) is a multifunctional serine protease with anticoagulant, cytoprotective, and anti-inflammatory activities. In addition to the cytoprotective effects of APC on endothelial cells, podocytes, and neurons, APC cleaves and detoxifies extracellular histones, a major component of neutrophil extracellular traps (NETs). NETs promote pathogen clearance but also can lead to thrombosis; the pathways that negatively regulate NETosis are largely unknown. Thus, we studied whether APC is capable of directly inhibiting NETosis via receptor-mediated cell signaling mechanisms. Here, by quantifying extracellular DNA or myeloperoxidase, we demonstrate that APC binds human leukocytes and prevents activated platelet supernatant or phorbol 12-myristate 13-acetate (PMA) from inducing NETosis. Of note, APC proteolytic activity was required for inhibiting NETosis. Moreover, antibodies against the neutrophil receptors endothelial protein C receptor (EPCR), protease-activated receptor 3 (PAR3), and macrophage-1 antigen (Mac-1) blocked APC inhibition of NETosis. Select mutations in the Gla and protease domains of recombinant APC caused a loss of NETosis. Interestingly, pretreatment of neutrophils with APC prior to induction of NETosis inhibited platelet adhesion to NETs. Lastly, in a nonhuman primate model of Escherichia coli-induced sepsis, pretreatment of animals with APC abrogated release of myeloperoxidase from neutrophils, a marker of neutrophil activation. These findings suggest that the anti-inflammatory function of APC at therapeutic concentrations may include the inhibition of NETosis in an EPCR-, PAR3-, and Mac-1-dependent manner, providing additional mechanistic insight into the diverse functions of neutrophils and APC in disease states including sepsis.

Iron deficiency (ID) is frequent but difficult to diagnose in critically ill patients. ID may be responsible for prolonged post-ICU hospital stays, since it results in fatigue, muscle weakness and anaemia. Hepcidin, the key iron metabolism hormone, may be a good marker of ID in these patients. The aim of this study is to determine whether using mass spectrometry hepcidin determination to diagnose (and treat) ID after prolonged ICU stays may reduce patients' subsequent hospital stays and costs in comparison with conventional (ferritin) methods.This is a randomised, controlled, single-blinded, multicentre medico-economic study. Hepcidin quantification will be performed in anaemic (WHO criteria) critically ill adults about to be discharged, after a stay ≥5days. In the intervention arm (hepcidin) results will be given to the ICU-physicians, and not in the control arm. ID Treatment will be recommended in intervention arm: IV iron when hepcidin is20μg/L; IV iron+erythropoietin when hepcidin is between 20-41μg/L; in the control arm: IV iron when ferritin300μg/L and Transferrin saturation20%. The primary endpoint will be the number of days spent in hospital 90 days after ICU discharge and the direct hospital costs. Secondary endpoints will be anaemia and iron deficiency on D15, fatigue and the proportion of patients alive and at home on D30 and D90.The results of this study will show whether diagnosing iron deficiency using MS hepcidin determination methods is liable to reduce patients' post-ICU hospital stay and costs, as well as their anaemia and fatigue.

International audience; Background: 5-aminolevulinic acid (ALA) is the first precursor of heme biosynthesis pathway. The exogenous addition of ALA to cells leads to protoporphyrin IX (PPIX) accumulation that has been exploited in photodynamic diagnostic and photodynamic therapy. Several types of ALA transporters have been described depending on the cell type, but there was no clear entry pathway for erythroid cells. The 18 kDa translocator protein (TSPO) has been proposed to be involved in the transport of porphyrins and heme analogs.Results: ALA-induced PPIX accumulation in erythroleukemia cells (UT-7, K562) was impaired by PK 11195, a competitive inhibitor of both transmembrane proteins TSPO (1 and 2). PK 11195 did not modify the activity of the enzymes of heme biosynthesis, suggesting that ALA entry at the plasma membrane was the limiting factor. In contrast, porphobilinogen (PBG)-induced PPIX accumulation was not affected by PK 11195, suggesting that plasma membrane TSPO2 is a selective transporter of ALA. Overexpression of TSPO2 at the plasma membrane of erythroleukemia cells increased ALA-induced PPIX accumulation, confirming the role of TSPO2 in the import of ALA into the cells.Conclusions: ALA-induced PPIX accumulation in erythroid cells involves TSPO2 as a selective translocator through the plasma membrane. Significance: This is the first characterization of molecular mechanisms involving a new actor in ALA transport in ALA-induced PPIX accumulation in erythroleukemia cells, which could be inhibited by specific drug ligands.

INTRODUCTION Hepcidin is a key factor that regulates iron homeostasis. In hemodialysis patients (HD), a high hepcidin level may decrease intestinal iron absorption and reduce the efficacy of Oral iron vs Intravenous iron therapy. Whether the hepcidin level in HD could guide oral iron therapy is unclear. METHODS We report a monocentric study on nine "erythropoietin (EPO)-free" patients (without recombinant human EPO [rHU-EPO] for at least 6 months) and normal hepcidin level (

Candida albicans can form biofilm on tissues and medical devices, becoming, in that case, less susceptible to antifungal agents. Treatment of candidiasis associated with the formation of C. albicans biofilms is restricted to echinocandins and lipid forms of amphotericin B. This study investigated the activity of micafungin and resveratrol modified molecule (EB487) against C. albicans biofilms. The anti-biofilm growth (Bgrowth) and anti-preformed biofilm (Bpreformed) activities of micafungin (0 to 3.94 μM) and EB487 (0 to 20.32 mM) were comparatively studied separately and combined, using XTT, flow cytometry and cell counts approaches. Concentrations causing 50% inhibition of the studied steps (IC50) were evaluated. When tested separately, IC50 Bgrowth was obtained for 4.8 mM and 0.13 μM of EB487 and micafungin respectively, and IC50 Bpreformed for 3.6 mM and 0.06 μM of EB487 and micafungin respectively. Micafungin used alone was not able to totally eradicate fungi. Micafungin combined with EB487 displayed synergistic activity (both anti-growth- and anti-preformed biofilm-activities). Optimal combination concentrations were EB487 (≤9.12 mM -strain ATCC 28367™ or ≤8.12 mM -strain CAI4-p), micafungin (≤0.05 μM for both) and caused a total eradication of fungi. Dose reduction indexes obtained using these concentrations were at least 9 (micafungin) and 3.2 (EB487) for both anti-biofilm growth- and anti-preformed biofilm-activities. Combinations indexes were consistently below one, demonstrating a synergistic relationship between micafungin and EB487 in these conditions. This study demonstrated the strong anti-biofilm activity of EB487 and highlighted its synergistic potential when combined with micafungin. EB487 is a promising semi-synthetic molecule with prophylactic and curative interests in fighting C. albicans biofilms.

Clinical severity is heterogeneous among patients suffering from congenital erythropoietic porphyria (CEP) suggesting a modulation of the disease (UROS deficiency) by environmental factors and modifier genes. A KI model of CEP due to a missense mutation of UROS gene present in human has been developed on 3 congenic mouse strains (BALB/c, C57BL/6, and 129/Sv) in order to study the impact of genetic background on disease severity. To detect putative modifiers of disease expression in congenic mice, hematologic data, iron parameters, porphyrin content and tissue samples were collected. Regenerative hemolytic anemia, a consequence of porphyrin excess in RBCs, had various expressions: 129/Sv mice were more hemolytic, BALB/c had more regenerative response to anemia, C57BL/6 were less affected. Iron status and hemolysis level were directly related: C57BL/6 and BALB/c had moderate hemolysis and active erythropoiesis able to reduce iron overload in the liver, while, 129/Sv showed an imbalance between iron release due to hemolysis and erythroid use. The negative control of hepcidin on the ferroportin iron exporter appeared strain specific in the CEP mice models tested. Full repression of hepcidin was observed in BALB/c and 129/Sv mice, favoring parenchymal iron overload in the liver. Unchanged hepcidin levels in C57BL/6 resulted in retention of iron predominantly in reticuloendothelial tissues. These findings open the field for potential therapeutic applications in the human disease, of hepcidin agonists and iron depletion in chronic hemolytic anemia.

International audience; Hepcidin is the hyposideremic hormone regulating iron metabolism. It is a defensin-like disulfide-bonded peptide with antimicrobial activity. The main site of hepcidin production is the liver where its synthesis is modulated by iron, inflammation and erythropoietic signaling. However, hepcidin locally produced in several peripheral organs seems to be an important actor for the maintenance of iron homeostasis in these organs. This review highlights the presence of peripheral hepcidin and its potential functions. Understanding the role of extrahepatic hepcidin could be of great physiological and therapeutic importance for several specific pathologies.

Aim Relatively few haemodialysis (HD) patients remain independent of recombinant human erythropoietin ('rHU-EPO free patients'). We investigated the role of EPO and hepcidin, two key hormones involved in anaemia. Methods We report a monocentric case-control series. Iron status, EPO and hepcidin levels were analysed in 15 Adult HD (Age > 18 years) with a stable haemoglobin (Hb) level that have not received rHU-EPO for at least 6 months (=rHU-EPO free patients); and in 60 controls with a stable rHU-EPO dose and Hb level. Results The rHU-EPO free patients had a higher Hb level compared to controls (12.1 ± 0.99 g/dL vs 11.1 ± 0.73, P = 0.0014), and a lower ferritin level (183 ± 102 vs 312 ± 166 ng/mL, P = 0.001). Hepcidin levels were lower in the rHU-EPO free patients (12.53 ± 10.46 ng/mL) compared to the controls (37.95 ± 34.33 ng/mL), P = 0.0033. Hepcidin levels correlated significantly with ferritin levels; but neither with transferrin saturation, C-reactive protein nor EPO levels. Unsupervised analysis revealed that rHU-EPO free patients had a specific clinical/biological profile (presence of renal cyst, longer dialysis vintage, lower ferritin, and EPO and hepcidin levels compared to the control group). Finally, we showed that a lower ferritin level might be a surrogate marker of a lower hepcidin status in this population. Conclusion Recombinant human erythropoietin free patients seem to restore the EPO-hepcidin axis that is critical for erythropoiesis. A specific combination of clinical and biological parameters may help to detect future rHU-EPO free patients.

International audience; Erythropoiesis-stimulating agents are generally the first line of treatment of anemia in patients with lower-risk myelodysplastic syndrome. We prospectively investigated the predictive value of somatic mutations, and biomarkers of ineffective erythropoiesis including the flow cytometry RED score, serum growth-differentiation factor-15, and hepcidin levels. Inclusion criteria were no prior treatment with erythropoiesis-stimulating agents, low- or intermediate-1-risk myelodysplastic syndrome according to the International Prognostic Scoring System, and a hemoglobin level 4 (P=0.05) and a hepcidin:ferritin ratio 2000 pg/mL and a hepcidin:ferritin ratio

International audience; Myelodysplastic syndromes (MDS) with ring sideroblasts are hematopoietic stem cell disorders with erythroid dysplasia and mutations in the SF3B1 splicing factor gene. Patients with MDS with SF3B1 mutations often accumulate excessive tissue iron, even in the absence of transfusions, but the mechanisms that are responsible for their parenchymal iron overload are unknown. Body iron content, tissue distribution, and the supply of iron for eryth-ropoiesis are controlled by the hormone hepcidin, which is regulated by erythroblasts through secretion of the erythroid hormone erythroferrone (ERFE). Here, we identified an alternative ERFE transcript in patients with MDS with the SF3B1 mutation. Induction of this ERFE transcript in primary SF3B1-mutated bone marrow erythroblasts generated a variant protein that maintained the capacity to suppress hepcidin transcription. Plasma concentrations of ERFE were higher in patients with MDS with an SF3B1 gene mutation than in patients with SF3B1 wild-type MDS. Thus, hepcidin suppression by a variant ERFE is likely responsible for the increased iron loading in patients with SF3B1-mutated MDS, suggesting that ERFE could be targeted to prevent iron-mediated toxicity. The expression of the variant ERFE transcript that was restricted to SF3B1-mutated erythroblasts decreased in lenalidomide-responsive anemic patients, identifying variant ERFE as a specific biomarker of clonal erythropoiesis.

International audience; Objective:To compare the oxidative stress induced by IV iron infusion in critically ill patients and in healthy volunteers.Design:Multicenter, interventional study.Setting:Two ICUs and one clinical research center.Subjects:Anemic critically ill patients treated with IV iron and healthy volunteers.Interventions:IV infusion of 100 mg of iron sucrose.Measurements and Main Results:Thirty-eight anemic patients (hemoglobin, median [interquartile range] = 8.4 g/dL [7.7–9.2]) (men, 25 [66%]; aged 68 yr [48–77]; Simplified Acute Physiology Score II, 48.5 [39–59]) and 39 healthy volunteers (men, 18 [46%]; aged 42.1 yr [29–50]) were included. Blood samples were drawn before (H0) and 2, 6, and 24 hours (H2, H6, and H24) after a 60-minute iron infusion for the determination of nontransferrin bound iron, markers of lipid peroxidation—8α-isoprostanes, protein oxidation—advanced oxidized protein product, and glutathione reduced/oxidized. Iron infusion had no effect on hemodynamic parameter in patients and volunteers. At baseline, patients had much higher interleukin-6, C-reactive protein, and hepcidin levels. 8α-isoprostanes was also higher in patients at baseline (8.5 pmol/L [6.5–12.9] vs 4.6 pmol/L [3.5–5.5]), but the area under the curve above baseline from H0 to H6 was not different (p = 0.38). Neither was it for advanced oxidized protein product and nontransferrin bound iron. The area under the curve above baseline from H0 to H6 (glutathione reduced/oxidized) was lower in volunteers (p = 0.009). Eight patients had a second set of dosages (after the fourth iron infusion), showing higher increase in 8α-isoprostanes.Conclusions:In our observation, IV iron infusion does not induce more nontransferrin bound iron, lipid, or protein oxidation in patients compared with volunteers, despite higher inflammation, oxidative stress, and hepcidin levels and lower antioxidant at baseline. In contrary, iron induces a greater decrease in antioxidant, compatible with higher oxidative stress in volunteers than in critically ill patients.

Microcytic anemia is often due to disorder of globin genes. Here, we focus on rare monogenic microcytic anemias, We describe the diferent congenital forms that are due to mutations in genes implicated in iron homeostasis, the heme biosynthesis pathway, the cluster Fe-S biosynthesis pathway andmitochondrial proteins biosynthesis pathway. Among rare congenital microcytic anemias, most frequent forms are non syndromic sideroblastic anemias and iron refractory iron deficiency anemias (IRIDA). Sideroblastic anemias is characterized by mitochondrial iron overload and presence of ring sideroblasts in patient bone marrow.. IRIDA results from bi-allelic mutations of TMPRSS6 gene encoding Matriptase-2. Matriptase-2 protein is a transmembrane serine protease that plays an essential role in down-regulating hepcidin, the key regulator of iron homeostasis. The next generation sequencing would be helpful to identify the genes implicated in unexplained rare anemias.

Disturbance is an omnipresent selective factor that shapes plant strategies. While annual species that rely on rapid generative reproduction dominate in habitats frequently affected by severe disturbance, long-lived woody species occupy habitats where the effects of disturbance are weak. These are, however, the extremes in the disturbance gradient. Habitats under intermediate disturbance are occupied by the whole spectrum of plant strategies. In this study, we hypothesized that clonal herbs are better adapted to intermediate disturbance than non-clonal herbs because the characteristics of their bud bank and related belowground carbohydrate storage promote vegetative regeneration. In a greenhouse experiment, we tested the effects of disturbance on the survival and performance of 17 congeneric pairs of clonal and non-clonal herbs cultivated from seed. In addition to a non-disturbed control, we applied five disturbance treatments: biomass removal 2 cm above the soil surface, removal of 70 % of the aboveground biomass, late spring frost, flooding, and belowground injury. Mortality was negligible except the flooding treatment, where it was higher for non-clonal than for clonal plants. Total biomass was reduced more by the disturbance treatments for clonal than for non-clonal plants, suggesting that clonal species suffer more than non-clonal species. On the other hand, clonal plants had significantly greater total belowground biomass and R:S ratios than non-clonal plants, suggesting a strong investment in belowground organs by clonal plants. In response to disturbance, the SLA and SRL values increased in clonal plants but decreased in non-clonal plants, indicating that clonal and non-clonal plants differ in how they cope with disturbance. Although clonality is considered to be an adaptation to disturbance, our results indicate that, during the first year of life, clonal herbs are more sensitive to disturbance than non-clonal herbs, likely due to preferential investment in belowground biomass.

In this first in situ study of the dynamic availability of phytoplankton micronutrients, a SeaExplorer glider was combined with Diffusive Gradients in Thin Films and deployed in the Mediterranean Sea. On the basis of their labile metal complex pools, we discovered that Fe and Co can be potentially limiting and Cu co-limiting to diatom growth, contrary to the generally accepted view that phosphorus (phosphate) is the growth limiting element in the Mediterranean Sea. For flagellates and picoplankton, phosphorus remains the main element limiting growth. Our in situ measurements showed that organic complexes of Fe and Cu (>98% of total dissolved concentration), dissociate slower than inorganic complexes of Co, Cd and Ni (>99% of total dissolved concentration being free ions and inorganic complexes). This strengthens the potential growth limiting effect of Fe and Cu versus phosphate, which is present as a free ion and, thus, directly available for plankton. We acknowledge the skillful assistance of ALSEAMAR personnel for the preparation and the operation of SeaExplorer SEA010. We thank HERCULES Foundation (code: UABR/11/010) for funding of the High Resolution-ICPMS and SeaExplorer procurement sponsors DEME Group and Dr. G. Decadt. Support of this research from the Spanish Ministry MINECO (Project CTM2016-78798) is acknowledged.

Objective— Terminal complications of bacterial sepsis include development of disseminated intravascular consumptive coagulopathy. Bacterial constituents, including long-chain polyphosphates (polyP), have been shown to activate the contact pathway of coagulation in plasma. Recent work shows that activation of the contact pathway in flowing whole blood promotes thrombin generation and platelet activation and consumption distal to thrombus formation ex vivo and in vivo. Here, we sought to determine whether presence of long-chain polyP or bacteria in the bloodstream promotes platelet activation and consumption in a coagulation factor (F)XII-dependent manner. Approach and Results— Long-chain polyP promoted platelet P-selectin expression, microaggregate formation, and platelet consumption in flowing whole blood in a contact activation pathway-dependent manner. Moreover, long-chain polyP promoted local fibrin formation on collagen under shear flow in a FXI-dependent manner. Distal to the site of thrombus formation, platelet consumption was dramatically enhanced in the presence of long-chain polyP in the blood flow in a FXI- and FXII-dependent manner. In a murine model, long-chain polyP promoted platelet deposition and fibrin generation in lungs in a FXII-dependent manner. In a nonhuman primate model of bacterial sepsis, pre-treatment of animals with an antibody blocking FXI activation by FXIIa reduced lethal dose 100 Staphylococcus aureus –induced platelet and fibrinogen consumption. Conclusions— This study demonstrates that bacterial-type long-chain polyP promotes platelet activation in a FXII-dependent manner in flowing blood, which may contribute to sepsis-associated thrombotic processes, consumptive coagulopathy, and thrombocytopenia.

Institut George Lopez-1 (IGL-1) and Histidine-tryptophan-ketoglutarate (HTK) solutions are proposed as alternatives to UW (gold standard) in liver preservation. Their composition differs in terms of the presence/absence of oncotic agents such as HES or PEG, and is decisive for graft conservation before transplantation. This is especially so when fatty (steatotic) livers are used since these grafts are more vulnerable to ischemia insult during conservation. Their composition determines the extent of the subsequent reperfusion injury after transplantation. Aldehyde dehydrogenase-2 (ALDH2), a mitochondrial enzyme, has been reported to play a protective role in warm ischemia-reperfusion injury (IRI), but its potential in fatty liver cold ischemic injury has not yet been investigated. We evaluated the relevance of ALDH2 activity in cold ischemia injury when fatty liver grafts from Zucker Obese rats were preserved in UW, HTK, and IGL-1 solutions, in order to study the mechanisms involved. ALDH2 upregulation was highest in livers preserved in IGL-1. It was accompanied by a decrease in transaminases, apoptosis (Caspase 3 and TUNEL assay), and lipoperoxidation, which was concomitant with the effective clearance of toxic aldehydes such as 4-hydroxy-nonenal. Variations in ATP levels were also determined. The results were consistent with levels of NF-E2 p45-related factor 2 (Nrf2), an antioxidant factor. Here we report for the first time the relevance of mitochondrial ALDH2 in fatty liver cold preservation and suggest that ALDH2 could be considered a potential therapeutic target or regulator in clinical transplantation., This research was funded by Instituto de Salud Carlos III through FIS project PI 15/00110 co-funded by FEDER from Regional Development European Funds (European Union) and the FOIE GRAS project, which has received funding from the European Union’s Horizon 2020 Research and Innovation programme under the Marie Sklodowska-Curie Grant (Agreement No. 722619).