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Summary: Adult stem cells play a critical role in tissue repair and maintenance. In tissues with slow turnover, including skeletal muscle, these cells are maintained in a mitotically quiescent state yet remain poised to re-enter the cell cycle to replenish themselves and regenerate the tissue. Using a panomics approach we show that the PAX7/NEDD4L axis acts against muscle stem cell activation in homeostatic skeletal muscle. Our findings suggest that PAX7 transcriptionally activates the E3 ubiquitin ligase Nedd4L and that the conditional genetic deletion of Nedd4L impairs muscle stem cell quiescence, with an upregulation of cell cycle and myogenic differentiation genes. Loss of Nedd4L in muscle stem cells results in the expression of doublecortin (DCX), which is exclusively expressed during their in vivo activation. Together, these data establish that the ubiquitin proteasome system, mediated by Nedd4L, is a key contributor to the muscle stem cell quiescent state in adult mice.

Surveillance to better detect and respond to new pathogens remains a major challenge for global public health. The Pasteur Network recently held a brainstorming workshop located in Cameroon attended by Pasteur epidemiological teams from Niger, Central African Republic (CAR), Cameroon, Senegal, and Madagascar to discuss how the Pasteur Network in Africa could use the lessons of COVID-19 to set-up a pilot sentinel surveillance scheme given its expertise and involvement during the pandemic. The possibility of coupling sentinel syndromic and biological surveillance already implemented for influenza surveillance with the recent sequencing capacity put in place by the AFROSCREEN program prompted us to consider strengthening surveillance tools to target “Pathogen X” detection in Africa. The perspective project provided by the Pasteur Network teams and shared with other partners of the AFROSCREEN program will target strengthening of the diagnosis of severe acute respiratory infections (IRAS) and the surveillance of IRAS, the evaluation of the impact of SARS-CoV-2 on the epidemiology of IRAS, and the addition of the detection of new pathogens, called “Pathogen X,” based on sequencing capacity and epidemiological criteria from One Health approaches.

Abstract Long-living individuals (LLIs) escape age-related cardiovascular complications until the very last stage of life. Previous studies have shown that a Longevity-Associated Variant (LAV) of the BPI Fold Containing Family B Member 4 (BPIFB4) gene correlates with an extraordinarily prolonged life span. Moreover, delivery of the LAV-BPIFB4 gene exerted therapeutic action in murine models of atherosclerosis, limb ischemia, diabetic cardiomyopathy, and aging. We hypothesize that downregulation of BPIFB4 expression marks the severity of coronary artery disease (CAD) in human subjects, and supplementation of the LAV-BPIFB4 protects the heart from ischemia. In an elderly cohort with acute myocardial infarction (MI), patients with three-vessel CAD were characterized by lower levels of the natural logarithm (Ln) of peripheral blood BPIFB4 (p = 0.0077). The inverse association between Ln BPIFB4 and three-vessel CAD was confirmed by logistic regression adjusting for confounders (Odds Ratio = 0.81, p = 0.0054). Moreover, in infarcted mice, a single administration of LAV-BPIFB4 rescued cardiac function and vascularization. In vitro studies showed that LAV-BPIFB4 protein supplementation exerted chronotropic and inotropic actions on induced pluripotent stem cell (iPSC)-derived cardiomyocytes. In addition, LAV-BPIFB4 inhibited the pro-fibrotic phenotype in human cardiac fibroblasts. These findings provide a strong rationale and proof of concept evidence for treating CAD with the longevity BPIFB4 gene/protein.

Abstract Epigenetic regulation of histone H3K27 methylation has recently emerged as a key step during alternative immunoregulatory M2-like macrophage polarization; known to impact cardiac repair after Myocardial Infarction (MI). We hypothesized that EZH2, responsible for H3K27 methylation, could act as an epigenetic checkpoint regulator during this process. We demonstrate for the first time an ectopic EZH2, and putative, cytoplasmic inactive localization of the epigenetic enzyme, during monocyte differentiation into M2 macrophages in vitro as well as in immunomodulatory cardiac macrophages in vivo in the post-MI acute inflammatory phase. Moreover, we show that pharmacological EZH2 inhibition, with GSK-343, resolves H3K27 methylation of bivalent gene promoters, thus enhancing their expression to promote human monocyte repair functions. In line with this protective effect, GSK-343 treatment accelerated cardiac inflammatory resolution preventing infarct expansion and subsequent cardiac dysfunction in female mice post-MI in vivo. In conclusion, our study reveals that pharmacological epigenetic modulation of cardiac-infiltrating immune cells may hold promise to limit adverse cardiac remodeling after MI.

The neurovascular unit, comprised of vascular cell types that collectively regulate cerebral blood flow to meet the needs of coupled neurons, is paramount for the proper function of the central nervous system. The neurovascular unit gatekeeps blood-brain barrier properties, which experiences impairment in several central nervous system diseases associated with neuroinflammation and contributes to pathogenesis. To better understand function and dysfunction at the neurovascular unit and how it may confer inflammatory processes within the brain, isolation and characterization of the neurovascular unit is needed. Here, we describe a singular, standardized protocol to enrich and isolate microvessels from archived snap-frozen human and frozen mouse cerebral cortex using mechanical homogenization and centrifugation-separation that preserves the structural integrity and multicellular composition of microvessel fragments. For the first time, microvessels are isolated from postmortem ventromedial prefrontal cortex tissue and are comprehensively investigated as a structural unit using both RNA sequencing and Liquid Chromatography with tandem mass spectrometry (LC-MS/MS). Both the transcriptome and proteome are obtained and compared, demonstrating that the isolated brain microvessel is a robust model for the NVU and can be used to generate highly informative datasets in both physiological and disease contexts.

Introduction: Although the physiological role of the C-terminal hydrolase domain of the soluble epoxide hydrolase (sEH-H) is well investigated, the function of its N-terminal phosphatase activity (sEH-P) remains unknown. Objectives: This study aimed to assess in vivo the physiological role of sEH-P. Methods: CRISPR/Cas9 was used to generate a novel knock-in (KI) rat line lacking the sEH-P activity. Results: The sEH-P KI rats has a decreased metabolism of lysophosphatidic acids to monoacyglycerols. KI rats grew almost normally but with less weight and fat mass gain while insulin sensitivity was increased compared to wild-type rats. This lean phenotype was more marked in males than in female KI rats and mainly due to decreased food consumption and enhanced energy expenditure. In fact, sEH-P KI rats had an increased lipolysis allowing to supply fatty acids as fuel to potentiate brown adipose thermogenesis under resting condition and upon cold exposure. The potentiation of thermogenesis was abolished when blocking PPARγ, a nuclear receptor activated by intracellular lysophosphatidic acids, but also when inhibiting simultaneously sEH-H, showing a functional interaction between the two domains. Furthermore, sEH-P KI rats fed a high-fat diet did not gain as much weight as the wild-type rats, did not have increased fat mass and did not develop insulin resistance or hepatic steatosis. In addition, sEH-P KI rats exhibited enhanced basal cardiac mitochondrial activity associated with an enhanced left ventricular contractility and were protected against cardiac ischemia–reperfusion injury. Conclusion: Our study reveals that sEH-P is a key player in energy and fat metabolism and contributes together with sEH-H to the regulation of cardiometabolic homeostasis. The development of pharmacological inhibitors of sEH-P appears of crucial importance to evaluate the interest of this promising therapeutic strategy in the management of obesity and cardiac ischemic complications.

Abstract Background Poliomyelitis outbreaks due to pathogenic vaccine-derived polioviruses (VDPVs) are threatening and complicating the global polio eradication initiative. Most of these VDPVs are genetic recombinants with non-polio enteroviruses (NPEVs) of species C. Little is known about factors favoring this genetic macroevolution process. Since 2001, Madagascar has experienced several outbreaks of poliomyelitis due to VDPVs, and most of VDPVs were isolated in the south of the island. The current study explored some of the viral factors that can promote and explain the emergence of recombinant VDPVs in Madagascar. Methods Between May to August 2011, we collected stools from healthy children living in two southern and two northern regions of Madagascar. Virus isolation was done in RD, HEp-2c, and L20B cell lines, and enteroviruses were detected using a wide-spectrum 5ʹ-untranslated region RT-PCR assay. NPEVs were then sequenced for the VP1 gene used for viral genotyping. Results Overall, we collected 1309 stools, of which 351 NPEVs (26.8%) were identified. Sequencing revealed 33 types of viruses belonging to three different species: Enterovirus A (8.5%), Enterovirus B (EV-B, 40.2%), and Enterovirus C (EV-C, 51.3%). EV-C species included coxsackievirus A13, A17, and A20 previously described as putative recombination partners for poliovirus vaccine strains. Interestingly, the isolation rate was higher among stools originating from the South (30.3% vs. 23.6%, p-value = 0.009). EV-C were predominant in southern sites (65.7%) while EV-B predominated in northern sites (54.9%). The factors that explain the relative abundance of EV-C in the South are still unknown. Conclusions Whatever its causes, the relative abundance of EV-C in the South of Madagascar may have promoted the infections of children by EV-C, including the PV vaccine strains, and have favored the recombination events between PVs and NPEVs in co-infected children, thus leading to the recurrent emergence of recombinant VDPVs in this region of Madagascar.

Abstract The mosquito Aedes aegypti is the major vector of arboviruses like dengue, Zika and chikungunya viruses. Attempts to reduce arboviruses emergence focusing on Ae. aegypti control has proven challenging due to the increase of insecticide resistances. An emerging strategy which consists of releasing Ae. aegypti artificially infected with Wolbachia in natural mosquito populations is currently being developed. The monitoring of Wolbachia-positive Ae. aegypti in the field is performed in order to ensure the program effectiveness. Here, the reliability of the Matrix‑Assisted Laser Desorption Ionization‑Time Of Flight (MALDI‑TOF) coupled with the machine learning methods like Convolutional Neural Network (CNN) to detect Wolbachia in field Ae. aegypti was assessed for the first time. For this purpose, laboratory reared and field Ae. aegypti were analyzed. The results showed that the CNN recognized Ae. aegypti spectral patterns associated with Wolbachia-infection. The MALDI-TOF coupled with the CNN (sensitivity = 93%, specificity = 99%, accuracy = 97%) was more efficient than the loop-mediated isothermal amplification (LAMP), and as efficient as qPCR for Wolbachia detection. It therefore represents an interesting method to evaluate the prevalence of Wolbachia in field Ae. aegypti mosquitoes.

Abstract Biomarkers to identify patients without benefit from adding everolimus to endocrine treatment in metastatic breast cancer (MBC) are needed. We report the results of the Pearl trial conducted in five Belgian centers assessing 18F-FDG-PET/CT non-response (n = 45) and ctDNA detection (n = 46) after 14 days of exemestane-everolimus (EXE-EVE) to identify MBC patients who will not benefit. The metabolic non-response rate was 66.6%. Median PFS in non-responding patients (using as cut-off 25% for SUVmax decrease) was 3.1 months compared to 6.0 months in those showing response (HR: 0.77, 95% CI: 0.40–1.50, p = 0.44). The difference was significant when using a “post-hoc” cut-off of 15% (PFS 2.2 months vs 6.4 months). ctDNA detection at D14 was associated with PFS: 2.1 months vs 5.0 months (HR-2.5, 95% CI: 1.3–5.0, p = 0.012). Detection of ctDNA and/or the absence of 18F-FDG-PET/CT response after 14 days of EXE-EVE identifies patients with a low probability of benefiting from treatment. Independent validation is needed.

Abstract Post-translational modifications of cardiac proteins could participate to left contractile dysfunction resulting in heart failure. Using a rat model of ischemic heart failure, we showed an accumulation of phosphorylated desmin leading to toxic aggregates in cardiomyocytes, but the cellular mechanisms are unknown. The same rat model was used to decipher the kinases involved in desmin phosphorylation and the proteolytic systems present in rat and human failing hearts. We used primary cultures of neonate rat cardiomyocytes for testing specific inhibitors of kinases and for characterizing the autophagic processes able to clear desmin aggregates. We found a significant increase of active PKCζ, no modulation of ubitiquitin-proteasome system, a defect in macroautophagy, and an activation of chaperone-mediated autophagy in heart failure rats. We validated in vitro that PKCζ inhibition induced a significant decrease of GSK3β and of soluble desmin. In vitro activation of ubiquitination of proteins and of chaperone-mediated autophagy is able to decrease soluble and insoluble forms of desmin in cardiomyocytes. These data demonstrate a novel signaling pathway implicating activation of PKCζ in desmin phosphorylation associated with a defect of proteolytic systems in ischemic heart failure, leading to desmin aggrephagy. Our in vitro data demonstrated that ubiquitination of proteins and chaperone-mediated autophagy are required for eliminating desmin aggregates with the contribution of its chaperone protein, α-crystallin Β-chain. Modulation of the kinases involved under pathological conditions may help preserving desmin intermediate filaments structure and thus protect the structural integrity of contractile apparatus of cardiomyocytes by limiting desmin aggregates formation.

Abstract Aims In post‐menopausal women, incidence of heart failure with preserved ejection fraction is higher than in men. Hormonal replacement therapies did not demonstrate benefits. We tested whether the non‐steroidal mineralocorticoid receptor antagonist finerenone limits the progression of heart failure in ovariectomized (OVX) mice with metabolic disorders. Methods and results Ovariectomy was performed in 4‐month‐old mice, treated or not at 7 months old for 1 month with finerenone (Fine) 1 mg/kg/day. Left ventricular (LV) cardiac and coronary endothelial functions were assessed by echocardiography, catheterization, and myography. Blood pressure was measured by plethysmography. Insulin and glucose tolerance tests were performed. Exercise capacity and spontaneous activity were measured on treadmill and in combined indirect calorimetric cages equipped with voluntary running wheel. OVX mice presented LV diastolic dysfunction without modification of ejection fraction compared with controls (CTL), whereas finerenone improved LV filling pressure (LV end‐diastolic pressure, mmHg: CTL 3.48 ± 0.41, OVX 6.17 ± 0.30**, OVX + Fine 3.65 ± 0.55†, **P

Abstract Aims Acute decompensated heart failure (ADHF), a live‐threatening complication of heart failure (HF), associates a further decrease of the already by HF‐impaired cardiac function with an increase in heart rate. We evaluated, using a new model of ADHF, whether heart rate reduction (HRR) opposes the acute decompensation‐related aggravation of cardiovascular dysfunction. Methods and results Cardiac output (echocardiography), cardiac tissue perfusion (magnetic resonance imaging), pulmonary wet weight, and in vitro coronary artery relaxation (Mulvany) were assessed 1 and 14 days after acute decompensation induced by salt‐loading (1.8 g/kg, PO) in rats with well‐established HF due to coronary ligation. HRR was induced by administration of the If current inhibitor S38844, 12 mg/kg PO twice daily for 2.5 days initiated 12 h or 6 days after salt‐loading (early or delayed treatment, respectively). After 24 h, salt‐loading resulted in acute decompensation, characterized by a reduction in cardiac output (HF: 130 ± 5 mL/min, ADHF: 105 ± 8 mL/min; P

Abstract This study addressed the hypothesis that epoxyeicosatrienoic acids (EETs) synthesized by CYP450 and catabolized by soluble epoxide hydrolase (sEH) are involved in the maintenance of renal allograft function, either directly or through modulation of cardiovascular function. The impact of single nucleotide polymorphisms (SNPs) in the sEH gene EPHX2 and CYP450 on renal and vascular function, plasma levels of EETs and peripheral blood monuclear cell sEH activity was assessed in 79 kidney transplant recipients explored at least one year after transplantation. Additional experiments in a mouse model mimicking the ischemia–reperfusion (I/R) injury suffered by the transplanted kidney evaluated the cardiovascular and renal effects of the sEH inhibitor t-AUCB administered in drinking water (10 mg/l) during 28 days after surgery. There was a long-term protective effect of the sEH SNP rs6558004, which increased EET plasma levels, on renal allograft function and a deleterious effect of K55R, which increased sEH activity. Surprisingly, the loss-of-function CYP2C9*3 was associated with a better renal function without affecting EET levels. R287Q SNP, which decreased sEH activity, was protective against vascular dysfunction while CYP2C8*3 and 2C9*2 loss-of-function SNP, altered endothelial function by reducing flow-induced EET release. In I/R mice, sEH inhibition reduced kidney lesions, prevented cardiac fibrosis and dysfunction as well as preserved endothelial function. The preservation of EET bioavailability may prevent allograft dysfunction and improve cardiovascular disease in kidney transplant recipients. Inhibition of sEH appears thus as a novel therapeutic option but its impact on other epoxyfatty acids should be carefully evaluated.

Although metabolic complications are common in thalassemia patients, there is still an unmet need to better understand underlying mechanisms. We used unbiased global proteomics to reveal molecular differences between the th3/+ mouse model of thalassemia and wild-type control animals focusing on skeletal muscles at 8 weeks of age. Our data point toward a significantly impaired mitochondrial oxidative phosphorylation. Furthermore, we observed a shift from oxidative fibre types toward more glycolytic fibre types in these animals, which was further supported by larger fibre-type cross-sectional areas in the more oxidative type fibres (type I/type IIa/type IIax hybrid). We also observed an increase in capillary density in th3/+ mice, indicative of a compensatory response. Western blotting for mitochondrial oxidative phosphorylation complex proteins and PCR analysis of mitochondrial genes indicated reduced mitochondrial content in the skeletal muscle but not the hearts of th3/+ mice. The phenotypic manifestation of these alterations was a small but significant reduction in glucose handling capacity. Overall, this study identified many important alterations in the proteome of th3/+ mice, amongst which mitochondrial defects leading to skeletal muscle remodelling and metabolic dysfunction were paramount.

Introduction. This study addressed the hypothesis that subtotal nephrectomy associated with a high-phosphorus diet (5/6Nx + P) in rats represents a suitable animal model to mimic the cardiovascular consequences of chronic kidney disease (CKD) including calcified aortic valve disease (CAVD). Indeed, the latter contributes to the high morbidity and mortality of CKD patients and sorely lacks preclinical models for pathophysiological and pharmacological studies. Methods. Renal and cardiovascular function and structure were compared between sham-operated and 5/6 Nx rats + P 10 to 12 weeks after surgery. Results. As expected, 11 weeks after surgery, 5/6Nx + P rats developed CKD as demonstrated by their increase in plasma creatinine and urea nitrogen and decrease in glomerular filtration rate, estimated by using fluorescein-isothiocyanate-labelled sinistrin, anemia, polyuria, and polydipsia compared to sham-operated animals on a normal-phosphorus diet. At the vascular level, 5/6Nx + P rats had an increase in the calcium content of the aorta; a decrease in mesenteric artery dilatation in response to a stepwise increase in flow, illustrating the vascular dysfunction; and an increase in blood pressure. Moreover, immunohistology showed a marked deposition of hydroxyapatite crystals in the aortic valve of 5/6Nx + P rats. Echocardiography demonstrated that this was associated with a decrease in aortic valve cusp separation and an increase in aortic valve mean pressure gradient and in peak aortic valve velocity. Left-ventricular diastolic and systolic dysfunction as well as fibrosis were also present in 5/6Nx + P rats. Conclusion. This study demonstrates that 5/6Nx + P recapitulates the cardiovascular consequences observed in humans with CKD. In particular, the initiation of CAVD was shown, highlighting the interest of this animal model to study the mechanisms involved in the development of aortic stenosis and test new therapeutic strategies at an early stage of the disease.

Inhibitors of soluble epoxide hydrolase (sEH), which catalyzes the hydrolysis of various natural epoxides to their corresponding diols, present an opportunity for developing oral drugs for a range of human cardiovascular and inflammatory diseases, including, among others, diabetes and neuropathic pain. However, some evidence suggests that their administration may precipitate the development of pulmonary hypertension (PH). We thus evaluated the impact of chronic oral administration of the sEH inhibitor TPPU (N-[1-(1-Oxopropyl)-4-piperidinyl]-N′-[4-(trifluoromethoxy)phenyl]-urea) on hemodynamics, pulmonary vascular reactivity, and remodeling, as well as on right ventricular (RV) dimension and function at baseline and in the Sugen (SU5416) + hypoxia (SuHx) rat model of severe PH. Treatment with TPPU started 5 weeks after SU5416 injection for 3 weeks. No differences regarding the increase in pulmonary vascular resistance, remodeling, and inflammation, nor the abolishment of phenylephrine-induced pulmonary artery constriction, were noted in SuHx rats. In addition, TPPU did not modify the development of RV dysfunction, hypertrophy, and fibrosis in SuHx rats. Similarly, none of these parameters were affected by TPPU in normoxic rats. Complementary in vitro data demonstrated that TPPU reduced the proliferation of cultured human pulmonary artery-smooth muscle cells (PA-SMCs). This study demonstrates that inhibition of sEH does not induce nor aggravate the development of PH and RV dysfunction in SuHx rats. In contrast, a potential beneficial effect against pulmonary artery remodeling in humans is suggested.

Mainly constituted of glycosaminoglycans and proteoglycans, the glycocalyx is anchored in the plasma membrane, covering, in particular, the extracellular face of the arterial endothelium. Due to its complex three-dimensional (3D) architecture, the glycocalyx interacts with a wide variety of proteins, contributing to vascular permeability, the flow of mechanotransduction, and the modulation of local inflammatory processes. Alterations of glycocalyx structure mediate the endothelial dysfunction and contribute to the aggravation of peripheral vascular diseases. Therefore, the exploration of its ultrastructure becomes a priority to evaluate the degree of injury under physiopathological conditions and to assess the impact of therapeutic approaches. The objective of this study was to develop innovative approaches in electron microscopy to visualize the glycocalyx at the subcellular scale. Intravenous perfusion on rats with a fixing solution containing aldehyde fixatives enriched with lanthanum ions was performed to prepare arterial samples. The addition of lanthanum nitrate in the fixing solution allowed the enhancement of the staining of the glycocalyx for transmission electron microscopy (TEM) and to detect elastic and inelastic scattered electrons, providing complementary qualitative information. The strength of scanning electron microscopy (SEM) was used on resin-embedded serial sections, allowing rapid and efficient large field imaging and previous correlative TEM observations for ultrastructural fine details. To demonstrate the dynamic feature of the glycocalyx, 3D tomography was provided by dual-beam focus-ion-beam-SEM (FIB-SEM). These approaches allowed us to visualize and characterize the ultrastructure of the pulmonary artery glycocalyx under physiological conditions and in a rat pulmonary ischemia-reperfusion model, known to induce endothelial dysfunction. This study demonstrates the feasibility of combined SEM, TEM, and FIB-SEM tomography approaches on the same sample as the multiscale visualization and the identification of structural indicators of arterial endothelial glycocalyx integrity.

The study assessed the nutrient value and desirability of eight improved soybean varieties, for use in soymilk, tofu and as an ingredient to enhance staple foods. The soymilk, tofu, and soybean residue (okara) yields were determined across all varieties. The okara was subsequently used in composite with cassava, as a recipe refinement of gari, a popular cassava-based ready-to-eat food. Multiple composite ratios were compared against a control of 100% cassava gari; 80% cassava: 20% okara, 70% cassava: 30% okara, and 50% cassava: 50% okara. The soymilk and tofu from the various varieties and okara enriched-gari were also evaluated for proximate and sensory qualities (n = 50) using standard protocols. No differences (p > 0.05) existed among soybean varieties in terms of soymilk (p = 0.55; 13.0–14.1 L), tofu (p = 0.05; 0.12–0.15 kg/L) or okara (p = 0.08; 3.17–3.97 kg) yields. The proximate parameters evaluated for soymilk did not vary significantly (p > 0.05) among varieties. However, for total solids (3.33–7.93°Brix; p < 0.01) there were significant differences. Generally, there was an increasing trend in the crude protein, moisture, crude fat and total ash contents for the okara-enriched gari as the okara inclusion increased from 20 to 50%. Thus, the crude protein content of the 50% okara-enriched gari, the formulation with the highest okara incorporation was almost 11-times higher than the 100% cassava gari. The swelling capacity of the okara-enriched gari ranged from 3.29–5.47 and for water holding capacity 439.7–482.1%. The okara-enriched gari was equally preferred by consumers, except for colour which consumers were mostly indifferent towards. The 50%-okara enriched gari composite was compared equally with 100% cassava gari control. The sensory data showed that the “Favour” soybean variety was desirable for soymilk production while Salintuya 1 was desirable for tofu production. Recipe refinements using the desired varieties and compositing okara with cassava may help fill the protein gap among the vulnerable group in Ghana by improving the protein quality of ready-to-eat foods such as gari.

Dengue, Zika and chikungunya viruses cause significant human public health burdens in the world. These arboviruses are transmitted by vector mosquito species notably Aedes aegypti and Aedes albopictus. In the Pacific region, more vector species of arboviruses belonging to the Scutellaris Group are present. Due to the expansion of human travel and international trade, the threat of their dispersal in other world regions is on the rise. Strengthening of entomological surveillance ensuring rapid detection of introduced vector species is therefore required in order to avoid their establishment and the risk of arbovirus outbreaks. This surveillance relies on accurate species identification. The aim of this study was to assess the use of the Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) as a tool for an international identification and surveillance of these mosquito vectors of arboviruses. Field-mosquitoes belonging to 8 species (Ae. aegypti, Ae. albopictus, Aedes polynesiensis, Aedes scutellaris, Aedes pseudoscutellaris, Aedes malayensis, Aedes futunae and Culex quinquefasciatus) from 6 countries in the Pacific, Asian and Madagascar, were included in this study. Analysis provided evidence that a MALDI-TOF database created using mosquitoes from the Pacific region allowed suitable identification of mosquito species from the other regions. This technic was as efficient as the DNA sequencing method in identifying mosquito species. Indeed, with the exception of two Ae. pseudoscutellaris, an exact species identification was obtained for all individual mosquitoes. These findings highlight that the MALDI-TOF MS is a promising tool that could be used for a global comprehensive arbovirus vector surveillance.

Abstract Background Mosquito vectors cause a significant human public health burden through the transmission of pathogens. Due to the expansion of international travel and trade, the dispersal of these mosquito vectors and the pathogens they carry is on the rise. Entomological surveillance is therefore required which relies on accurate mosquito species identification. This study aimed to optimize the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for mosquito identification. Methods Aedes aegypti of the Bora-Bora strain and 11 field-sampled mosquito species were used in this study. Analyses were performed to study the impact of the trapping duration on mosquito identification with MALDI-TOF MS. The best preservation methods to use for short, medium and long-term preservation before MALDI-TOF MS analysis were also assessed. In addition, the number of specimens per species required for MALDI-TOF MS database creation was determined. The first MALDI-TOF database of New Caledonian mosquitoes was assembled and the optimal threshold for mosquito species identification according to the sensitivity and specificity of this technique was determined. Results This study showed that the identification scores decreased as the trapping duration increased. High identification scores were obtained for mosquitoes preserved on silica gel and cotton at room temperature and those frozen at − 20 °C, even after two months of preservation. In addition, the results showed that the scores increased according to the number of main spectrum patterns (MSPs) used until they reached a plateau at 5 MSPs for Ae. aegypti. Mosquitoes (n = 67) belonging to 11 species were used to create the MALDI-TOF reference database. During blind test analysis, 96% of mosquitoes tested (n = 224) were correctly identified. Finally, based on MALDI-TOF MS sensitivity and specificity, the threshold value of 1.8 was retained for a secure identification score. Conclusions MALDI-TOF MS allows accurate species identification with high sensitivity and specificity and is a promising tool in public health for mosquito vector surveillance.

Abstract Background Hypertonic sodium lactate (HSL) may be of interest during inflammation. We aimed to evaluate its effects during experimental sepsis in rats (cecal ligation and puncture (CLP)). Methods Three groups were analyzed (n = 10/group): sham, CLP-NaCl 0.9%, and CLP-HSL (2.5 mL/kg/h of fluids for 18 h after CLP). Mesenteric microcirculation, echocardiography, cytokines, and biochemical parameters were evaluated. Two additional experiments were performed for capillary leakage (Evans blue, n = 5/group) and cardiac hemodynamics (n = 7/group). Results HSL improved mesenteric microcirculation (CLP-HSL 736 [407–879] vs. CLP-NaCl 241 [209–391] UI/pixel, p = 0.0006), cardiac output (0.34 [0.28–0.43] vs. 0.14 [0.10–0.18] mL/min/g, p

The routine use of mechanical circulatory support during lung transplantation (LTx) is still controversial. The use of prophylactic human albumin (HA) or hypertonic sodium lactate (HSL) prime in mechanical circulatory support during LTx could prevent ischemia–reperfusion (IR) injuries and pulmonary endothelial dysfunction and thus prevent the development of pulmonary graft dysfunction. The objective was to investigate the impact of cardiopulmonary bypass (CPB) priming with HA and HSL compared to a CPB prime with Gelofusine (GF) on pulmonary endothelial dysfunction in a lung IR rat model. Rats were assigned to four groups: IR-CPB-GF group, IR-CPB-HA group, IR-CPB-HSL group and a sham group. The study of pulmonary vascular reactivity by wire myograph was the primary outcome. Glycocalyx degradation (syndecan-1 and heparan) was also assessed by ELISA and electron microscopy, systemic and pulmonary inflammation by ELISA (IL-1β, IL-10, and TNF-α) and immunohistochemistry. Clinical parameters were evaluated. We employed a CPB model with three different primings, permitting femoral–femoral assistance with left pulmonary hilum ischemia for IR. Pulmonary endothelium-dependent relaxation to acetylcholine was significantly decreased in the IR-CPB-GF group (11.9 ± 6.2%) compared to the IR-CPB-HA group (52.8 ± 5.2%, p < 0.0001), the IR-CPB-HSL group (57.7 ± 6.3%, p < 0.0001) and the sham group (80.8 ± 6.5%, p < 0.0001). We did not observe any difference between the groups concerning glycocalyx degradation, and systemic or tissular inflammation. The IR-CPB-HSL group needed more vascular filling and developed significantly more pulmonary edema than the IR-CPB-GF group and the IR-CPB-HA group. Using HA as a prime in CPB during Ltx could decrease pulmonary endothelial dysfunction’s IR-mediated effects. No effects of HA were found on inflammation.

Abstract Background Rabies remains a major public health problem in developing countries. Most fatal rabies cases, especially in children, result from dog bites and occur in low-income countries, such as those in Sub-Saharan Africa. Rabies can be controlled through mass dog vaccination and human deaths prevented through timely and appropriate post-exposure prophylaxis (PEP). As access to appropriate PEP remains a serious challenge for bite-victims, the aim of this study was to understand the use of PEP, to evaluate the knowledge, attitudes and practices with respect to rabies and to identify risk factors related to non-compliance with PEP to define recommendations for improving PEP in Senegal. Methods This study included patients with suspicion of rabies exposure who sought PEP at the Pasteur Institute of Dakar from April 2013 to March 2014. Patients with rabies clinical symptoms, those who had already started PEP and those with exposure outside Senegal or for more than 3 months were excluded. Data on risk factors and propensity to seek and complete PEP were collected using questionnaires and phone interviews. The association between acceptability and compliance with PEP and other independent variables were evaluated using multivariate regression analysis. Results Among the 905 patients enrolled into the study, 67% were male (sex ratio M/F, 2) and 46%, children under 15 years of age. Exposures by animal bites represented 87%, whereas the remainder were due to scratches or contact; 76% were classified as WHO category III and 88% were due to dogs. Among these patients, 7% refused to start PEP and 54.5% completed the full schedule. Main factors reported by non-compliant patients were vaccine costs and affordability, and knowledge on status of biting animal. Conclusion This study shows that despite the awareness about rabies dangers and prevention, only half of the patients completed the full PEP schedule. The following recommendations, such as free of charge prophylaxis or intradermal regimens as an alternative to intramuscular regimens, should be considered to increase the adherence to PEP at the Pasteur Institute of Dakar and in Senegal.

Abstract Background This pathophysiological study addressed the hypothesis that soluble epoxide hydrolase (sEH), which metabolizes the vasodilator and anti-inflammatory epoxyeicosatrienoic acids (EETs) to dihydroxyeicosatrienoic acids (DHETs), contributes to conduit artery endothelial dysfunction in type 2 diabetes. Methods and results Radial artery endothelium-dependent flow-mediated dilatation in response to hand skin heating was reduced in essential hypertensive patients (n = 9) and type 2 diabetic subjects with (n = 19) or without hypertension (n = 10) compared to healthy subjects (n = 36), taking into consideration cardiovascular risk factors, flow stimulus and endothelium-independent dilatation to glyceryl trinitrate. Diabetic patients but not non-diabetic hypertensive subjects displayed elevated whole blood reactive oxygen species levels and loss of NO release during heating, assessed by measuring local plasma nitrite variation. Moreover, plasma levels of EET regioisomers increased during heating in healthy subjects, did not change in hypertensive patients and decreased in diabetic patients. Correlation analysis showed in the overall population that the less NO and EETs bioavailability increases during heating, the more flow-mediated dilatation is reduced. The expression and activity of sEH, measured in isolated peripheral blood mononuclear cells, was elevated in diabetic but not hypertensive patients, leading to increased EETs conversion to DHETs. Finally, hyperglycemic and hyperinsulinemic euglycemic clamps induced a decrease in flow-mediated dilatation in healthy subjects and this was associated with an altered EETs release during heating. Conclusions These results demonstrate that an increased EETs degradation by sEH and altered NO bioavailability are associated with conduit artery endothelial dysfunction in type 2 diabetic patients independently from their hypertensive status. The hyperinsulinemic and hyperglycemic state in these patients may contribute to these alterations. Trial registration NCT02311075. Registered December 8, 2014.

Heart failure, mostly associated with cardiac hypertrophy, is a major cause of illness and death. Oxidative stress causes accumulation of reactive oxygen species (ROS), leading to mitochondrial dysfunction, suggesting that mitochondria-targeted therapies could be effective in this context. The purpose of this work was to determine whether mitochondria-targeted therapies could improve cardiac hypertrophy induced by mitochondrial ROS. We used neonatal (NCMs) and adult (ACMs) rat cardiomyocytes hypertrophied by isoproterenol (Iso) to induce mitochondrial ROS. A decreased interaction between sirtuin 3 and superoxide dismutase 2 (SOD2) induced SOD2 acetylation on lysine 68 and inactivation, leading to mitochondrial oxidative stress and dysfunction and hypertrophy after 24 h of Iso treatment. To counteract these mechanisms, we evaluated the impact of the mitochondria-targeted antioxidant mitoquinone (MitoQ). MitoQ decreased mitochondrial ROS and hypertrophy in Iso-treated NCMs and ACMs but altered mitochondrial structure and function by decreasing mitochondrial respiration and mitophagy. The same decrease in mitophagy was found in human cardiomyocytes but not in fibroblasts, suggesting a cardiomyocyte-specific deleterious effect of MitoQ. Our data showed the importance of mitochondrial oxidative stress in the development of cardiomyocyte hypertrophy. We observed that targeting mitochondria by MitoQ in cardiomyocytes impaired the metabolism through defective mitophagy, leading to accumulation of deficient mitochondria.

Objectives: Cardiovascular diseases (CVD) remain the leading cause of morbimortality in patients with chronic kidney disease (CKD). The aim of this study was to assess the cardiovascular impact of the pharmacological inhibition of soluble epoxide hydrolase (sEH), which metabolizes the endothelium-derived vasodilatory and anti-inflammatory epoxyeicosatrienoic acids (EETs) to dihydroxyeicosatrienoic acid (DHETs), in the 5/6 nephrectomy (Nx) mouse model.Methods and Results: Compared to sham-operated mice, there was decrease in EET-to-DHET ratio 3 months after surgery in vehicle-treated Nx mice but not in mice treated with the sEH inhibitor t-AUCB. Nx induced an increase in plasma creatinine and in urine albumin-to-creatinine ratio as well as the development of kidney histological lesions, all of which were not modified by t-AUCB. In addition, t-AUCB did not oppose Nx-induced blood pressure increase. However, t-AUCB prevented the development of cardiac hypertrophy and fibrosis induced by Nx, as well as normalized the echocardiographic indices of diastolic and systolic function. Moreover, the reduction in endothelium-dependent flow-mediated dilatation of isolated mesenteric arteries induced by Nx was blunted by t-AUCB without change in endothelium-independent dilatation to sodium nitroprusside.Conclusion: Inhibition of sEH reduces the cardiac remodelling, and the diastolic and systolic dysfunctions associated with CKD. These beneficial effects may be mediated by the prevention of endothelial dysfunction, independent from kidney preservation and antihypertensor effect. Thus, inhibition of sEH holds a therapeutic potential in preventing type 4 cardiorenal syndrome.

Introduction: Endoplasmic reticulum stress (ERS) is involved in inflammatory organ failure. Our objective was to describe ERS, its unfolded protein response (UPR) expression/kinetics during cardiac surgery with cardiopulmonary bypass (CPB) and its association with postoperative organ failure (OF).Methods: Prospective study conducted on patients undergoing cardiac surgery with CPB. Blood samples were taken before (Pre-CPB), 2 h (H2-CPB) and 24 h (H24-CPB) after CPB. Plasma levels of 78 kDa Glucose- Regulated Protein (GRP78, final effector of UPR) were evaluated by ELISA. The expression of genes coding for key elements of UPR (ATF6, ATF4, sXBP1, CHOP) was evaluated by quantitative PCR performed on total blood. OF was defined as invasive mechanical ventilation and/or acute kidney injury and/or hemodynamic failure requiring catecholamines.Results: We included 46 patients, GRP78 was decreased at H2-CPB [1,328 (878–1,730) ng/ml vs. 2,348 (1,655–3,730) ng/ml Pre-CPB; p < 0.001] but returned to basal levels at H24-CPB [2,068 (1,436–3,005) ng/ml]. The genes involved in UPR had increased expression at H2 and H24. GRP78 plasma levels in patients with OF at H24-CPB (n = 10) remained below Pre-CPB levels [−27.6 (−51.5; −24.2)%] compared to patients without OF (n = 36) in whom GRP78 levels returned to basal levels [0.6 (−28.1; 26.6)%; p < 0.01]. H24-CPB ATF6 and CHOP expressions were lower in patients with OF than in patients without OF [2.3 (1.3–3.1) vs. 3.0 (2.7–3.7), p < 0.05 and 1.3 (0.9–2.0) vs. 2.2 (1.7–2.9), p < 0.05, respectively].Conclusions: Low relative levels of GRP78 and weak UPR gene expression appeared associated with postoperative OF. Further studies are needed to understand ERS implication during acute organ failure in humans.

Abstract Introduction Imeglimin, a glucose‐lowering agent targeting mitochondrial bioenergetics, decreases reactive oxygen species (ROS) overproduction and improves glucose homeostasis. We investigated whether this is associated with protective effects on metabolic syndrome‐related left ventricular (LV) and vascular dysfunctions. Methods We used Zucker fa/fa rats to assess the effects on LV function, LV tissue perfusion, LV oxidative stress and vascular function induced by imeglimin administered orally for 9 or 90 days at a dose of 150 mg/kg twice daily. Results Compared to untreated animals, 9‐ and 90‐day imeglimin treatment decreased LV end‐diastolic pressure and LV end‐diastolic pressure‐volume relation, increased LV tissue perfusion and decreased LV ROS production. Simultaneously, imeglimin restored acetylcholine‐mediated coronary relaxation and mesenteric flow‐mediated dilation. One hour after imeglimin administration, when glucose plasma levels were not yet modified, imeglimin reduced LV mitochondrial ROS production and improved LV function. Ninety‐day imeglimin treatment reduced related LV and kidney fibrosis and improved kidney function. Conclusion In a rat model, mimicking Human metabolic syndrome, imeglimin immediately countered metabolic syndrome‐related cardiac diastolic and vascular dysfunction by reducing oxidative stress/increased NO bioavailability and improving myocardial perfusion and after 90‐day treatment myocardial and kidney structure, effects that are, at least in part, independent from glucose control.

In New Caledonia (NC), Aedes aegypti is the only proven vector of dengue virus (DENV), which is the most prevalent arbovirosis in NC. Since World War II, the four DENV serotypes have circulated regularly in NC. The epidemiological profile, however, has evolved over the last ten years, with the persistence of DENV-1 circulation and the co-circulation of several DENV serotypes. The current study evaluated the ability of Ae. aegypti from NC to transmit four DENV serotypes (and two DENV-1 genotypes) isolated during recent outbreaks in NC. An Ae. aegypti F1 generation was twice independently orally challenged with each DENV strain (107 FFU/ml). Infection, dissemination and transmission rates and transmission efficiency were measured at day 7 and 14 post-exposure, as well as the quantity of infectious virus particles. Mosquito infection was observed as early as 7 days post-infection. Infection rates between 18 and 58% were measured for all DENV serotypes/genotypes tested. Although dissemination rates ranged from 78 to 100%, transmission efficiencies were low, with values not exceeding 21% at 14 days post-infection for all DENV strains. This study shows that NC Ae. aegypti are moderately competent for DENV in laboratory conditions. In link with epidemiological data, these results suggest implication of other factors in the sustained circulation of DENV-1 in New Caledonia.

Abstract Zika virus (ZIKV) is a Flavivirus that is transmitted to humans by Aedes mosquitoes. ZIKV is divided into two phylogenetic lineages, African and Asian. In the Asian lineage, Pacific and American clades have been linked to the recent worldwide outbreak of ZIKV. The aim of this study was to measure the vector competence of Aedes aegypti for seven ZIKV strains belonging to both lineages. We demonstrate that Ae. aegypti from New Caledonia (NC), South Pacific region, is a low-competence vector for Asian ZIKV (37% transmission efficiency after 9 days post-infection) compared to recent ZIKV isolates from African (10% transmission efficiency) and Asian lineages (

Introduction: Protein Tyrosine Phosphatase 1B (PTP1B) and endoplasmic reticulum stress (ERS) are involved in the septic inflammatory response. Their inhibition is associated with improved survival in murine models of sepsis. The objective was to describe PTP1B and ERS expression during septic shock in human.Material and Methods: Prospective study including patients admitted to intensive care unit (ICU) for septic shock. Blood samples were collected on days 1 (D1), 3 and 5 (D5). Quantitative PCR (performed from whole blood) evaluated the expression of genes coding for PTP1B (PTPN1) and key elements of ERS (GRP78, ATF6, CHOP) or for endothelial dysfunction-related markers (ICAM1 and ET1). We analyzed gene variation between D5 and D1, collected glycemic parameters, insulin resistance and organ failure was evaluated by Sequential Organ Failure Assessment (SOFA) score.Results: We included 44 patients with a mean SAPS II 50 ± 16 and a mortality rate of 13.6%. Between D1 and D5, there was a significant decrease of PTPN1 (p < 0.001) and ATF6 (p < 0.001) expressions. Their variations of expression were correlated with SOFA variation (PTPN1, r = 0.35, CI 95% [0.05; 0.54], p = 0.03 and ATF6, r = 0.45 CI 95% [0.20; 0.65], p < 0.001). We did not find any correlation between PTPN1 expression and insulin resistance or glycemic parameters. Between D1 and D5, ATF6 and PTPN1 expressions were correlated with that of ET1.Conclusions: Our study has evaluated for the first time the expression of PTP1B and ERS in patients with septic shock, revealing that gene expression variation of PTPN1 and ATF6 are partly correlated with the evolution of septic organ failure and with endothelial dysfunction markers expression.

Cardiovascular diseases (CVD) are the leading cause of premature death and disability in humans that are closely related to lipid metabolism and signaling. This study aimed to assess whether circulating lysophospholipids (LPL), lysophosphatidic acids (LPA) and monoacylglycerols (MAG) may be considered as potential therapeutic targets in CVD. For this objective, plasma levels of 22 compounds (13 LPL, 6 LPA and 3 MAG) were monitored by liquid chromatography coupled with tandem mass spectrometry (HPLC/MS2) in different rat models of CVD, i.e., angiotensin-II-induced hypertension (HTN), ischemic chronic heart failure (CHF) and sugen/hypoxia(SuHx)-induced pulmonary hypertension (PH). On one hand, there were modest changes on the monitored compounds in HTN (LPA 16:0, 18:1 and 20:4, LPC 16:1) and CHF (LPA 16:0, LPC 18:1 and LPE 16:0 and 18:0) models compared to control rats but these changes were no longer significant after multiple testing corrections. On the other hand, PH was associated with important changes in plasma LPA with a significant increase in LPA 16:0, 18:1, 18:2, 20:4 and 22:6 species. A deleterious impact of LPA was confirmed on cultured human pulmonary smooth muscle cells (PA-SMCs) with an increase in their proliferation. Finally, plasma level of LPA(16:0) was positively associated with the increase in pulmonary artery systolic pressure in patients with cardiac dysfunction. This study demonstrates that circulating LPA may contribute to the pathophysiology of PH. Additional experiments are needed to assess whether the modulation of LPA signaling in PH may be of interest.

Abstract Although several risk factors such as infarct size have been identified, the progression of heart failure (HF) remains difficult to predict in clinical practice. Using an experimental rat model of post-myocardial infarction (MI), we previously identified 45 proteins differentially modulated during HF by proteomic analysis. This study sought to identify microRNAs (miRNAs) able to regulate these proteins and to test their relevance as biomarkers for HF. In silico bioinformatical analysis selected 13 miRNAs related to the 45 proteins previously identified. These miRNAs were analyzed in the rat and in cohorts of patients phenotyped for left ventricular remodeling (LVR). We identified that 3 miRNAs, miR-21-5p, miR-23a-3p and miR-222-3p, and their target Mn superoxide dismutase (SOD2) were significantly increased in LV and plasma of HF-rats. We found by luciferase activity a direct interaction of miR-222-3p with 3′UTR of SOD2. Transfection of human cardiomyocytes with miR-222-3p mimic or inhibitor induced respectively a decrease and an increase of SOD2 expression. Circulating levels of the 3 miRNAs and their target SOD2 were associated with high LVR post-MI in REVE-2 patients. We demonstrated for the first time the potential of microRNAs regulating SOD2 as new circulating biomarkers of HF.