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Although thioredoxin-interacting protein (TXNIP) is involved in a variety of biologic functions, the contribution of endothelial TXNIP has not been well defined. To investigate the endothelial function of TXNIP, we generated a TXNIP knockout mouse on the Cdh5-cre background (TXNIPfl/fl cdh5cre). Control (TXNIPfl/fl) and TXNIPfl/fl cdh5cre mice were fed a high protein-low carbohydrate (HP-LC) diet for 3 mo to induce metabolic stress. We found that TXNIPfl/fl and TXNIPfl/fl cdh5cre mice on an HP-LC diet displayed impaired glucose tolerance and dyslipidemia concretizing the metabolic stress induced. We evaluated the impact of this metabolic stress on mice with reduced endothelial TXNIP expression with regard to arterial structure and function. TXNIPfl/fl cdh5cre mice on an HP-LC diet exhibited less endothelial dysfunction than littermate mice on an HP-LC diet. These mice were protected from decreased aortic medial cell content, impaired aortic distensibility, and increased plasminogen activator inhibitor 1 secretion. This protective effect came with lower oxidative stress and lower inflammation, with a reduced NLRP3 inflammasome expression, leading to a decrease in cleaved IL-1β. We also show the major role of TXNIP in inflammation with a knockdown model, using a TXNIP-specific, small interfering RNA included in a lipoplex. These findings demonstrate a key role for endothelial TXNIP in arterial impairments induced by metabolic stress, making endothelial TXNIP a potential therapeutic target.-Bedarida, T., Domingues, A., Baron, S., Ferreira, C., Vibert, F., Cottart, C.-H., Paul, J.-L., Escriou, V., Bigey, P., Gaussem, P., Leguillier, T., Nivet-Antoine, V. Reduced endothelial thioredoxin-interacting protein protects arteries from damage induced by metabolic stress in vivo.

International audience; Background:Genetically engineered animals are essential for gaining a proper understanding of the disease mechanisms of cystic fibrosis (CF). The rat is a relevant laboratory model for CF because of its zootechnical capacity, size, and airway characteristics, including the presence of submucosal glands.Methods:We describe the generation of a CF rat model (F508del) homozygous for the p.Phe508del mutation in the transmembrane conductance regulator (Cftr) gene. This model was compared to new Cftr -/- rats (CFTR KO). Target organs in CF were examined by histological staining of tissue sections and tooth enamel was quantified by micro-computed tomography. The activity of CFTR was evaluated by nasal potential difference (NPD) and short-circuit current measurements. The effect of VX-809 and VX-770 was analyzed on nasal epithelial primary cell cultures from F508del rats.Results:Both newborn F508del and Knock out (KO) animals developed intestinal obstruction that could be partly compensated by special diet combined with an osmotic laxative. The two rat models exhibited CF phenotypic anomalies such as vas deferens agenesis and tooth enamel defects. Histology of the intestine, pancreas, liver, and lungs was normal. Absence of CFTR function in KO rats was confirmed ex vivo by short-circuit current measurements on colon mucosae and in vivo by NPD, whereas residual CFTR activity was observed in F508del rats. Exposure of F508del CFTR nasal primary cultures to a combination of VX-809 and VX-770 improved CFTR-mediated Cl- transport.Conclusions:The F508del rats reproduce the phenotypes observed in CFTR KO animals and represent a novel resource to advance the development of CF therapeutics.

The acute and chronic consequences of long-distance running on brain function have received little attention. The impact of such a hard-physical burden associated with sleep privation during such events such has never been explored in terms of neuropsychological function and brain damage. METHODS Blood samples were collected from 4 athletes before, during and at the end of one of two races: Grand Raid de la Reunion 2017 (GRR: 165 km, elevation gain: 9529 m, 2 runners) and Trail de la Bourbon 2017 (TB: 111 km, elevation gain: 6433 m, 2 runners). Serum S100B and NSE levels were measured for each runner before, during and after the race. RESULTS Serum S100B levels (normal range: < 0.15 μg/L) increased early during the race and remained high up to the end of the race in all 4 runners (range: 0.17-0.59 μg/L). NSE level (normal range: < 15 μg/L) increased in 3 of the 4 runners (range: 16.8-39.2 μg/L). CONCLUSIONS This preliminary study shows the potential interest of S100B and NSE serum assessment during long-distance races. Further studies are needed to confirm these results and to investigate the origins and significance of this increase in brain injury markers.

Cystic fibrosis (CF) is caused by defective Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein. Morbidity is mainly due to early airway infection. We hypothesized that S. aureus clearance during the first hours of infection was impaired in CF human Airway Surface Liquid (ASL) because of a lowered pH. The ASL pH of human bronchial epithelial cell lines and primary respiratory cells from healthy controls (WT) and patients with CF was measured with a pH microelectrode. The antimicrobial capacity of airway cells was studied after S. aureus apical infection by counting surviving bacteria. ASL was significantly more acidic in CF than in WT respiratory cells. This was consistent with a defect in bicarbonate secretion involving CFTR and SLC26A4 (pendrin) and a persistent proton secretion by ATP12A. ASL demonstrated a defect in S. aureus clearance which was improved by pH normalization. Pendrin inhibition in WT airways recapitulated the CF airway defect and increased S. aureus proliferation. ATP12A inhibition by ouabain decreased bacterial proliferation. Antimicrobial peptides LL-37 and hBD1 demonstrated a pH-dependent activity. Normalizing ASL pH might improve innate airway defense in newborns with CF during onset of S. aureus infection. Pendrin activation and ATP12A inhibition could represent novel therapeutic strategies to normalize pH in CF airways.

IntroductionA reduction in pulmonary artery relaxation is a key event in the pathogenesis of pulmonary arterial hypertension (PAH). Cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction in airway epithelial cells plays a central role in cystic fibrosis; CFTR is also expressed in pulmonary arteries and has been shown to control endothelium-independent relaxation.Aim and objectivesWe aimed to delineate the role of CFTR in PAH pathogenesis through observational and interventional experiments in human tissues and animal models.Methods and resultsReverse-transcriptase quantitative PCR, confocal imaging and electron microscopy showed that CFTR expression was reduced in pulmonary arteries from patients with idiopathic PAH (iPAH) and in rats with monocrotaline-induced pulmonary hypertension (PH). Moreover, using myography on human, pig and rat pulmonary arteries, we demonstrated that CFTR activation induces pulmonary artery relaxation. CFTR-mediated pulmonary artery relaxation was reduced in pulmonary arteries from iPAH patients and rats with monocrotaline- or chronic hypoxia-induced PH. Long-term in vivo CFTR inhibition in rats significantly increased right ventricular systolic pressure, which was related to exaggerated pulmonary vascular cell proliferation in situ and vessel neomuscularisation. Pathologic assessment of lungs from patients with severe cystic fibrosis (F508del-CFTR) revealed severe pulmonary artery remodelling with intimal fibrosis and medial hypertrophy. Lungs from homozygous F508delCftr rats exhibited pulmonary vessel neomuscularisation. The elevations in right ventricular systolic pressure and end diastolic pressure in monocrotaline-exposed rats with chronic CFTR inhibition were more prominent than those in vehicle-exposed rats.ConclusionsCFTR expression is strongly decreased in pulmonary artery smooth muscle and endothelial cells in human and animal models of PH. CFTR inhibition increases vascular cell proliferation and strongly reduces pulmonary artery relaxation.

Food allergies can have significant effects on morbidity and on quality of life. Therefore, the development of efficient approaches to reduce the risk of developing food allergies is of considerable interest. The aim of this study was to identify and select probiotic strains with preventive properties against allergies using a combination of in vitro and in vivo approaches. To that end, 31 strains of bifidobacteria and lactic acid bacteria were screened for their immunomodulatory properties in two cellular models, namely, human peripheral blood mononuclear cells (PBMCs) and T helper 2 (Th2)-skewed murine splenocytes. Six strains inducing a high interleukin-10 (IL-10)/IL-12p70 ratio and a low secretion of IL-4 on the two cellular models were selected, and their protective impact was tested in vivo in a murine model of food allergy to β-lactoglobulin. Three strains showed a protective impact on sensitization, with a decrease in allergen-specific IgE, and on allergy, with a decrease in mast cell degranulation. Analysis of the impact of these three strains on the T helper balance revealed different mechanisms of action. The Lactobacillus salivarius LA307 strain proved to block Th1 and Th2 responses, while the Bifidobacterium longum subsp. infantis LA308 strain induced a pro-Th1 profile and the Lactobacillus rhamnosus LA305 strain induced pro-Th1 and regulatory responses. These results demonstrate that a combination of in vitro and in vivo screening is effective in probiotic strain selection and allowed identification of three novel probiotic strains that are active against sensitization in mice.

Although its powerful impact on most co-morbidities has been widely demonstrated, the metabolic outcomes of bariatric surgery (BS) show a great heterogeneity among patients. Haplotypes of one of the major antioxidant enzyme, catalase (CAT), are associated with hypertension, dyslipidemia, and diabetes. The haplotype referred to as CAT1 includes homozygous carriers of CATH1 [-844G,-89A,-20T], whereas CAT2 haplotype includes heterozygous carriers (CATH1/CATH2) and CATH2 homozygous [-844A,-89T,-20C]. The aim of our study was to evaluate the impact of CAT1 and CAT2 haplotypes on traditional cardiovascular and metabolic markers one year after BS in a women population. The 294 women with a body mass index (BMI) >35 kg/m2 were followed-up for one year after BS, monitoring their anthropometric, metabolic and inflammatory parameters. CAT1 patients had significantly improved diastolic blood pressure (DBP) and Creactive protein (CRP) levels compared to CAT2 one year after BS. In untreated women at baseline, the change of CRP one year after BS was higher in CAT1 patients. In the population of women receiving at least one anti-lipidic, anti-hypertensive or anti-diabetic treatment at baseline, DBP and fat mass were lower one year after BS in CAT1 patients and the greater change of fat mass was associated with a higher change of adiponectin. The results highlight the beneficial impact of the CAT1 haplotype on traditional cardiovascular and metabolic parameters after BS. Our findings suggest that the CAT1 haplotype could be implicated in the level of metabolic and cardiovascular improvement after BS.

International audience; High-protein-low-carbohydrate (HP-LC) diets have become widespread. Yet their deleterious consequences, especially on glucose metabolism and arteries, have already been underlined. Our previous study (2) has already shown glucose intolerance with major arterial dysfunction in very old mice subjected to an HP-LC diet. The hypothesis of this work was that this diet had an age-dependent deleterious metabolic and cardiovascular outcome. Two groups of mice, young and adult (3 and 6 mo old), were subjected for 12 wk to a standard or to an HP-LC diet. Glucose and lipid metabolism was studied. The cardiovascular system was explored from the functional stage with Doppler-echography to the molecular stage (arterial reactivity, mRNA, immunohistochemistry). Young mice did not exhibit any significant metabolic modification, whereas adult mice presented marked glucose intolerance associated with an increase in resistin and triglyceride levels. These metabolic disturbances were responsible for cardiovascular damages only in adult mice, with decreased aortic distensibility and left ventricle dysfunction. These seemed to be the consequence of arterial dysfunctions. Mesenteric arteries were the worst affected with a major oxidative stress, whereas aorta function seemed to be maintained with an appreciable role of cyclooxygenase-2 to preserve endothelial function. This study highlights for the first time the age-dependent deleterious effects of an HP-LC diet on metabolism, with glucose intolerance and lipid disorders and vascular (especially microvessels) and cardiac functions. This work shows that HP-LC lead to equivalent cardiovascular alterations, as observed in very old age, and underlines the danger of such diet.

International audience; Perturbations of energy balance induce compensatory processes that may alter expected weight loss. In obese patients, our aim was to investigate the relationships that occurred between fasting plasma concentrations of anorexigenic peptides and metabolic parameters, appetite, physical capacity, and weight loss in the 5 first days of a program associating exercise and caloric reduction. Thirteen obese women were monitored from day 1 to day 5 with 2 exercise sessions in day 2 and day 4. We measured, in a fasted state, changes in body weight, hunger ratings, and plasma concentrations of fatty acids, triglycerides, leptin, insulin, amylin, peptide YY, and insulin-resistance index. Physical performance was assessed by a 6-min walking test. The program resulted in significantly reduced body weight (0.75±0.4 kg; p=0.001), of plasma concentrations of triglycerides, insulin, amylin, peptide YY, and the insulin-resistance index, and also increased fatty acids (p

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Several recently published clinical trials have extended our knowledge on the use of resveratrol (RVT) to treat several human pathological and metabolic disorders. Herein, we present insights into the metabolism, biological effects, and toxicity of RVT in humans. Recent data show that RVT exhibits antioxidant and anti-inflammatory activities. It can also improve glucose and lipid metabolism, it acts on cardiovascular parameters, and can modify some pathways involved in carcinogenesis. However, these effects are mostly tiny and the results are sometimes controversial as they depend on the protocols (i.e. dose, form of administration, patients' characteristics, adjuvant therapy, etc.). Toxicological data confirm that RVT is well tolerated. Any adverse effects (mainly concerning the abdomen), at doses of ≥0.5 g/day for long periods, remain moderate and reversible. Nevertheless, the efficacy and safety of RVT need to be further investigated.

cope : Trans-resveratrol is widely studied for its potentially beneficial effects on numerous disorders. It is rapidly metabolized and its metabolites can exhibit biological activity. The present study aimed to investigate whether acute or sustained trans-resveratrol administration impacted on the distribution of trans-resveratrol and its metabolites in brain, heart, and liver. Methods and results : We used UHPLC-Q-TOF in full-scan mode to identify and assess large numbers of resveratrol metabolites. For acute intake, mice were overfed with a single dose of trans-resveratrol (150 mg/kg) and organs were collected after 30 and 60 min. For sustained intake, trans-resveratrol was given in the chow (0.04% w/w corresponding to 40 mg/kg/d), and plasma and the organs were collected after 3 months of this resveratrol diet. We found that trans-resveratrol-3-O-glucuronide and resveratrol-3-sulfate were the main metabolites found after acute intake, and free trans-resveratrol (in the brain and heart) and dihydro-resveratrol derivatives were found after sustained administration Conclusions : Our results show notable differences between acute and sustained administration of trans-resveratrol and distribution of trans-resveratrol and its metabolites in mouse heart, brain, and liver. The results suggest a strategy for development of galenic forms of resveratrol. This article is protected by copyright. All rights reserved

The nasal epithelium of the mouse closely mimics the bioelectrical phenotype of the human airways. Ion transport across the nasal epithelium induces a nasal transepithelial potential difference. Its measurement by a relatively non-invasive method adapted from humans allows in vivo longitudinal measurements of CFTR-dependent ionic transport in the murine nasal mucosa. This test offers a useful tool to assess CFTR function in preclinical studies for novel therapeutics modulating CFTR activity. Here we extensively review work done to assess transepithelial transport in the murine respiratory epithelium in the basal state and after administration of CFTR modulators. Factors of variability and discriminative threshold between the CF and the WT mice for different readouts are discussed.

International audience; Aging leads to a high prevalence of glucose intolerance and cardiovascular diseases, with oxidative stress playing a potential role. Resveratrol has shown promising effects on glucose tolerance and tends to improve endothelial function in elderly patients. Thioredoxin-interacting protein (TXNIP) was recently proposed as a potential link connecting glucose metabolism to oxidative stress. Here, we investigated the resveratrol-induced improvement of arterial aging phenotype in old mice and the expression of aortic TXNIP. Using an in vivo model of old mice with or without 3-month resveratrol treatment, we investigated the effects of resveratrol on age-related impairments from a cardiovascular Doppler analysis, to a molecular level, by studying inflammation and oxidative stress factors. We found a dual effect of resveratrol, with a decrease of age-related glucose intolerance and oxidative stress imbalance leading to reduced matrix remodeling that forestalls arterial aging phenotype in terms of intima-media thickness and arterial distensibility. These results provide the first evidence that aortic TXNIP mRNA and protein nuclear expressions are increased in the arterial aging and decreased by resveratrol treatment. In conclusion, we demonstrated that resveratrol helped to restore several aging impaired processes in old mice, with a decrease of aortic TXNIP mRNA and protein nuclear expressions

Impaired glucose tolerance is common during aging. The transcription factor PAX6 is involved in glucose homeostasis. Computational promoter sequence analysis of the catalase gene highlighted a putative PAX6 binding site on the rs769214 polymorphism A allele. Creation of this binding site has been suggested to explain renutrition inefficiency in malnourished elderly patients. Our aim was to evaluate the link between the rs769214 polymorphism of the catalase gene and glucose homeostasis in malnourished elderly patients at inclusion and during renutrition. Thirty-three malnourished elderly Caucasian inpatients were recruited. Nutritional and inflammatory statuses were assessed and a multiplex adipokine analysis was conducted at inclusion and discharge from the Geriatric Nutritional Care Unit at Charles-Foix Hospital (Ivry-sur-Seine, France). Serum glucagon, PAI-1, and TNF-α levels were significantly lower in the A-allele carriers at inclusion. During renutrition, A-allele carriers exhibited increased serum glucagon, PAI-1, and TNF-α variation. After renutrition, levels of these parameters were similar for A-allele carriers and G-allele carriers. A logistic ordinal multivariate regression analysis linked only variation of glucagon to rs769214 SNP. These results support a role for catalase SNP in the efficiency of renutrition in malnourished elderly patients via the modulation of glucagon secretion, probably involving PAX6.

Numerous data are now available on the beneficial properties of the polyphenolic compound resveratrol including its anti-inflammatory and antitumor effects. However, few studies have been performed with resveratrol in humans, and the results of these studies appear fragmentary and sometimes contradictory due to variations in conditions of administration, protocols and methods of assessment. This review article presents the results of recent studies investigating the pharmacokinetics, bioavailability, and toxicity of resveratrol in humans. Resveratrol is well absorbed, rapidly metabolized, mainly into sulfo and glucuronides conjugates which are eliminated in urine. Resveratrol seems to be well tolerated and no marked toxicity was reported. These data are important in the context of human efficacy studies, and they provide further support for the use of resveratrol as a pharmacological drug in human medicine.

Resume Le vieillissement arteriel se traduit par un epaississement et une rigidification de la paroi des arteres – ce qui correspond a la definition de l'arteriosclerose. Les mecanismes biologiques, cellulaires et moleculaires mis en jeu sont complexes et une partie d'entre eux sont communs aux processus qui conduisent aux lesions focales atherosclereuses des arteres de gros et moyen calibres. La degradation de l'arbre vasculaire au cours du vieillissement aboutit a des evenements cliniques cardio- et cerebro-vasculaires dont les consequences sont tres importantes en terme de morbi-mortalite dans les pays industrialises. L'objectif de cet article de synthese est de faire le point sur la physiopathologie et la biologie du vieillissement arteriel de type arteriosclereux, en detaillant les donnees actuelles qui le rapprochent ou le distinguent des lesions observees au cours de l'atherosclerose, en particulier au niveau de l'etape de la calcification arterielle. Pour citer cet article : C.-H. Cottart et al., C. R. Biologies 332 (2009).

In cystic fibrosis (CF) patients, the major alteration in pulmonary function is due to peripheral airway obstruction. In the present study, we investigated the possibility that alterations in the extrathoracic airways, particularly in the trachea that expresses high levels of CFTR (CF transmembrane conductance regulator), may contribute to respiratory dysfunction. We performed morphological analyses of the trachea and airway functional studies in adult Cftr knockout (Cftr(-/-)) and F508del-CFTR mice and their controls. Macroscopic and histological examination of the trachea showed the presence of one to seven disrupted or incomplete cartilage rings in Cftr(-/-) mice (23/25) while only a few Cftr(+/+) mice (6/25) had one abnormal ring. Tracheal defects were mainly localized in the proximal trachea. In 14 Cftr(-/-) mice, frontal disruption of the first three to six rings below the cricoid cartilage were associated with upper tracheal constriction. Similar tracheal abnormalities were detected in adult F508del-CFTR and in newborn Cftr(-/-) and F508del-CFTR mice. Tracheal and ventilatory function analyses showed in Cftr(-/-) mice a decreased contractile response of the proximal trachea and a reduced breathing rate due to an increase in the inspiratory and expiratory times. In F508del-CFTR mice, the expiratory time was longer than in controls. Therefore, these structural and functional abnormalities detected in adult and newborn CF mouse models may represent congenital malformations related to CFTR dysfunction. These results raise important questions concerning the mechanisms governing tracheal development within the context of CFTR protein dysfunction and the implication of such abnormalities in the pathogenesis of airway disease in CF.

To elucidate the impact of nutrition in cystic fibrosis (CF), we compared the phenotypic traits of Cftr -/- mice fed either a lipid-enriched liquid diet (Peptamen) or a standard chow combined with polyethylenglycol osmotic laxative (PEG), two strategies commonly used to prevent intestinal obstruction in CF mice. Survival, growth, liver, and ventilatory status were determined in Cftr -/- and Cftr +/+ mice, followed-up until 120 d. Ventilation was recorded in conscious animals using whole-body plethysmography. We found that the survival rate was similar in Peptamen and PEG Cftr -/- mice. Cftr -/- mice had lower minute ventilation than Cftr +/+ mice, whatever the diet. Both Cftr -/- and Cftr +/+ mice fed Peptamen displayed preadult growth delay compared with PEG-treated animals. Despite subsequent growth catch-up, Cftr -/- mice remained smaller than Cftr +/+ mice, whatever the diet. All Peptamen fed Cftr -/- mice showed hepatomegaly and liver steatosis, which also occurred but to a lesser extent in Peptamen fed Cftr +/+ animals. Therefore, while both treatment strategies are similarly efficient to avoid high mortality at weaning, Peptamen induces preadult growth delay and liver steatosis. These effects of diet are important to consider in future animal studies and also prompt to evaluate high-energy diets in CF patients.

The grey mouse lemur (Microcebus murinus) is a non-human primate used to study the ageing process. Resveratrol is a polyphenol that may increase lifespan by delaying age-associated pathologies. However, no information about resveratrol absorption and metabolism is available for this primate. Resveratrol and its metabolites were qualitatively and quantitatively analyzed in male mouse-lemur plasma (after 200 mg.kg−1 of oral resveratrol) by ultra-high performance liquid chromatography (UHPLC), coupled to a quadrupole-time-of-flight (Q-TOF) mass spectrometer used in full-scan mode. Data analyses showed, in MSE mode, an ion common to resveratrol and all its metabolites: m/z 227.072, and an ion common to dihydro-resveratrol metabolites: m/z 229.08. A semi-targeted study enabled us to identify six hydrophilic resveratrol metabolites (one diglucurono-conjugated, two monoglucurono-conjugated, one monosulfo-conjugated and two both sulfo- and glucurono-conjugated derivatives) and three hydrophilic metabolites of dihydro-resveratrol (one monoglucurono-conjugated, one monosulfo-conjugated, and one both sulfo- and glucurono-conjugated derivatives). The presence of such metabolites has been already detected in the mouse, rat, pig, and humans. Free resveratrol was measurable for several hours in mouse-lemur plasma, and its two main metabolites were trans-resveratrol-3-O-glucuronide and trans-resveratrol-3-sulfate. Free dihydro-resveratrol was not measurable whatever the time of plasma collection, while its hydrophilic metabolites were present at 24 h after intake. These data will help us interpret the effect of resveratrol in mouse lemurs and provide further information on the inter-species characteristics of resveratrol metabolism.

International audience; Aging leads to increased insulin resistance and arterial dysfunction, with oxidative stress playing an important role. This study explored the metabolic and arterial effects of a chronic treatment with resveratrol, an antioxidant polyphenol compound that has been shown to restore insulin sensitivity and decrease oxidative stress, in old mice with or without a high-protein diet renutrition care. High-protein diet tended to increase insulin resistance and atheromatous risk. Resveratrol improved insulin sensitivity in old mice fed standard diet by decreasing homeostasis model of assessment-insulin resistance and resistin levels. However, resveratrol did not improve insulin resistance status in old mice receiving the high-protein diet. In contrast, resveratrol exhibited deleterious effects by increasing inflammation state and superoxide production and diminishing aortic distensibility. In conclusion, we demonstrate that resveratrol has beneficial or deleterious effects on insulin sensitivity and arterial function, depending on nutritional status in our models.

The aim of this study was to evaluate the protective or deleterious effects of endogenous nitric oxide (NO) on liver cells during hepatic ischemia-reperfusion (IR) in the rat. Injury to hepatocytes and endothelial cells was evaluated by determining cytolysis-marker activity in plasma (alanine transaminase [ALT]; aspartate transaminase [AST]) and plasma hyaluronic acid (HA) concentration. Clamping the hepatic pedicle for 45 minutes caused a significant increase in plasma AST and ALT activity after 30 minutes of reperfusion, which reached a maximum (+270% and +740%, respectively) after 6 hours of reperfusion. Plasma HA concentration was significantly higher (+130%) only after 6 hours of reperfusion. Administration of a nonselective NO synthase (NOS) inhibitor, Nω-nitro-L -arginine (L -NNA; 10 mg/kg iv), 30 minutes before IR, caused marked aggravation of postischemic liver injury, as shown by plasma ALT and AST activity and HA concentration. This deleterious effect was partially prevented by the simultaneous injection of L -arginine, the endogenous NO precursor (100 mg/kg iv). Interestingly, L -arginine alone limited postischemic damage (AST, −25%; ALT, −45%; HA, −21% vs. untreated IR rats at 6 hours reperfusion). Pretreatment with the Guanosine 3′:5′-cyclic monophosphate-independent vasodilator, prazosin, partially reversed L -NNA effects, but it did not protect untreated IR animals. Pretreatment with aminoguanidine, a selective inhibitor of inducible NOS, did not aggravate hepatic IR injury. Thus, endogenous NO, probably produced by an early and transient activation of a constitutive NOS, protects both hepatocytes and endothelial cells against liver ischemia–reperfusion injury, and this effect is not entirely a result of vasorelaxation.

International audience; BackgroundAlthough many conventional factors have been associated with the development of arterial aging, cardiovascular diseases remain the first cause of death in old age. Therefore, identification of new risk factors may prove promising for monitoring this serious health problem. Oxidative stress and particularly catalase (CAT), an antioxidant enzyme, play an important role in endothelial cell pathophysiology, in shear stress response and ultimately in arterial aging.ObjectiveExamine the relationships between CAT haplotypes and phenotypes of arterial aging (mean internal diameter, mean intima–media thickness of the common carotid arteries (CCA), presence of atheromatous plaques) in two French cohorts.Methods and results564 middle-aged French individuals (mean age 53 ± 12 years) from two cohorts (ERA and STANISLAS cohorts) were included in the study. Blood pressure, CCA intima–media thickness, CCA internal diameter and number of atheromatous plaques were measured. Catalase rs769214 SNP genotyping was performed. We identified a CAT haplotype that influences arterial aging. Individuals carrying the CAT2 haplotype had a higher mean internal diameter of CCA with aging and/or with an SBP ≥140 mmHg and were associated with a greater number of atheromatous plaques than CAT1 haplotypes carriers. This CAT2 haplotype appeared as an independent risk factor of arterial aging, similarly to previously identified factors such as age, systolic blood pressure, male, sex, tobacco use, hs-CRP, BMI and diabetes.ConclusionThe present study highlights the roles of CAT haplotypes in arterial aging and underlines the beneficial impact of the CAT1 haplotype on mean internal diameter of the CCA and atheromatous plaque number as well as on potential associated diseases.

Resveratrol is a polyphenol that has numerous interesting biological properties, but, per os, it is quickly metabolized. Some of its metabolites are more concentrated than resveratrol, may have greater biological activities, and may act as a kind of store for resveratrol. Thus, to understand the biological impact of resveratrol on a physiological system, it is crucial to simultaneously analyze resveratrol and its metabolites in plasma. This study presents an analytical method based on UHPLC-Q-TOF mass spectrometry for the quantification of resveratrol and of its most common hydrophilic metabolites. The use of (13)C- and D-labeled standards specific to each molecule led to a linear calibration curve on a larger concentration range than described previously. The use of high resolution mass spectrometry in the full scan mode enabled simultaneous identification and quantification of some hydrophilic metabolites not previously described in mice. In addition, UHPLC separation, allowing run times lower than 10 min, can be used in studies that requiring analysis of many samples.

Distinguishing latent tuberculosis (LTB) from tuberculosis (TB) disease may be challenging in children. Here, we analyzed cytokine profiles that can distinguish the two infection stages in a nonendemic country (France). Immunocompetent children with LTB (n = 6) or TB disease (n = 8) (median age: 6.2 and 5.7 years, respectively) were analyzed. Four young uninfected children were included as controls. A Luminex assay evaluated cytokine responses to Mycobacterium tuberculosis antigens. Poor interleukin-4 (IL-4) and IL-10 responses precluded analysis of these cytokines. Interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), IL-2, and T-helper type 1 (Th1) cytokines and IL-5, IL-13, T-helper type 2 (Th2) cytokines were simultaneously induced by antigens in 14/14 infected but 0/4 uninfected children. Th1 cytokine levels were similar in LTB and TB disease: IFN-γ: 12,254 and 10,495 pg/ml; IL-2: 2,097 and 1,869 pg/ml; and TNF-α: 1,020 and 2,875 pg/ml, respectively. Th2 cytokine levels were similar and even higher in LTB than in TB disease: IL-5: 23 and 10 pg/ml; IL-13: 284 and 109 pg/ml, respectively. Positive correlation of cytokine levels, whether Th1 or Th2, was observed. Higher (P = 0.008) TNF-α/IL-2 ratios distinguished 6/8 active TB disease cases from 6/6 LTB cases. TNF-α/IL-2 ratio may discriminate TB disease from LTB in immunocompetent children. Larger studies in TB endemic settings must verify these results.

Background & Aims Patients with cystic fibrosis (CF) have poorly defined defects in biliary function. We evaluated the effects of cystic fibrosis transmembrane conductance regulator (CFTR) deficiency on the enterohepatic disposition of bile acids (BAs). Methods Bile secretion and BA homeostasis were investigated in Cftr tm1Unc ( Cftr −/− ) and CftrΔF508 (ΔF508) mice. Results Cftr −/− and ΔF508 mice did not grow to normal size, but did not have liver abnormalities. The gallbladders of Cftr −/− mice were enlarged and had defects in emptying, based on 99m technetium-mebrofenin scintigraphy or post-prandial variations in gallbladder volume; gallbladder contraction in response to cholecystokinin-8 was normal. Cftr −/− mice had abnormal gallbladder bile and duodenal acidity, and overexpressed the vasoactive intestinal peptide—a myorelaxant factor for the gallbladder. The BA pool was larger in Cftr −/− than wild-type mice, although there were no differences in fecal loss of BAs. Amounts of secondary BAs in portal blood, liver, and bile of Cftr −/− mice were much lower than normal. Expression of genes that are induced by BAs, including fibroblast growth factor-15 and BA transporters, was lower in the ileum but higher in the gallbladders of Cftr −/− mice, compared with wild-type mice, whereas enzymes that synthesize BA were down-regulated in livers of Cftr −/− mice. This indicates that BAs underwent a cholecystohepatic shunt, which was confirmed using cholyl-(Ne-NBD)-lysine as a tracer. In Cftr −/− mice, cholecystectomy reversed most changes in gene expression and partially restored circulating levels of secondary BAs. The ΔF508 mice overexpressed vasoactive intestinal peptide and had defects in gallbladder emptying and in levels of secondary BAs, but these features were less severe than in Cftr −/− mice. Conclusions Cftr −/− and CftrΔF508 mice have defects in gallbladder emptying that disrupt enterohepatic circulation of BAs. These defects create a shunt pathway that restricts the amount of toxic secondary BAs that enter the liver.

Txnip (thioredoxin-interacting protein) is a protein with multifunctional roles in cellular responses and stress-related diseases. Txnip is involved in intracellular redox regulation and has been recently described as a possible link between redox state and metabolism. trans-Resveratrol (T-res) is a natural phytoalexin with antiproliferative, antiapoptotic and antioxidative effects. However, to date there have been no reports of the implication of Txnip in a model of liver acute stress such as ischemia-reperfusion (I/R) and no work has looked for a T-res effect on Txnip. Here we studied the effects of a post-ischemic treatment of T-res on the liver thioredoxin (Trx)/Txnip system and investigated whether the T-res effects were dependent on NO production. In this work, liver I/R induced hepatic Txnip expression and T-res inhibited I/R Txnip expression. This decrease in Txnip expression by T-res was associated with an increase in liver Trx redox activity and a decrease in hepatic I/R-induced Trx-1 expression with no effect on Trx-2, on plasma Trx redox activity or on liver and plasma Trx reductase activity, independently of NO production. In conclusion, these results show that in our model, not only did T-res protect Trx redox activity by diminishing the Txnip protein expression; it also reduced secretion of Trx1. This is the first report of a major implication of the Trx1/Txnip system in hepatic I/R injuries. It also affirms the importance of the antioxidant effect of T-res on the Trx1/Txnip system.

Oxidative and inflammatory processes are elicited during hepatic post-ischemic reperfusion and generate liver damage. This study investigated the early anti-inflammatory effect of trans-resveratrol (T-res) and its consequences on the late self-aggravating inflammatory process in liver ischemia-reperfusion (I/R). Partial hepatic ischemia was initiated in rats for 1 h and T-res (0.02 and 0.2 mg/kg) was administered intravenously 5 min before starting reperfusion for 3 h. Plasma levels of aminotransferases and cytokines (tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6) and hepatic neutrophil recruitment were assessed. Hepatic expression of stress protein (heat-shock protein (HSP-70), heme oxygenase-1(HO-1)) and cytokine (TNF-alpha, IL-1beta, keratinocyte chemoattractant (KC)) mRNA was investigated. I/R caused an increase in aminotransferase levels and increased polymorphonuclear cell infiltration. Post-ischemic treatment with T-res (0.02 and 0.2 mg/kg) resulted in a significant decrease in aminotransferase, IL-1beta and IL-6 plasma levels by about 40%, 60% and 40%, respectively, compared to the vehicle I/R group. Post-ischemic treatment with T-res (0.02 mg/kg) also significantly decreased hepatic neutrophil recruitment. TNF-alpha, IL-1beta, KC and HO-1 hepatic mRNA expression was reduced by T-res without any change in HSP-70 mRNA. This T-res mediated decrease in early release of cytokines and neutrophil recruitment led to a reduction in the late inflammatory process. T-resveratrol might be useful in the prevention of inflammation secondary to hepatic surgery or liver transplantation.

The solubility and molar absorptivity of trans- and cis-resveratrol isomers in aqueous solvents are poorly described. This study aimed to develop and describe a new simple method for the determination of trans- and cis-resveratrol concentrations in aqueous solutions. Up to 300 μM trans-resveratrol was dissolved in water by sonication for 2 h. Cis-resveratrol was obtained by exposing a 100-μM trans-resveratrol aqueous solution to sunlight for 8 h, followed by HPLC separation and analysis by mass spectrometry (resveratrol oxidation products were absent). Accurate values for UV absorbance in water were e λ max = e 304 nm = 30 335 M − 1 c m − 1 , ɛ286 nm = 23 400 M−1 cm−1 for trans-resveratrol and e λ max = e 286 nm = 14 986 M − 1 c m − 1 , ɛ304 nm = 9515 M−1 cm−1 for cis-resveratrol. These values allowed us to propose formulae to assess the trans-/cis-resveratrol ratio in water, using a simple and reliable UV–vis spectrophotometric method. Statistical analysis revealed no significant difference between our UV method and the commonly used HPLC method. All these data are transferable to 150 mM NaCl and 10 mM phosphate buffer solutions, which could be particularly useful for cell culture, ex vivo and in vivo studies.

Arterial ageing - arteriosclerosis - is characterised by both thickening and stiffening of the walls of large and medium arteries. The molecular and cellular mechanisms (i.e. endothelial dysfunction, matrix remodelling, ...) involved in this process are complex, and at least in part common to atherosclerotic injury. Arterial stiffness is strongly associated with cardiovascular disease and an increased risk of morbidity and mortality. The aim of this review is to provide an update on the pathophysiology and the biological process of arterial ageing and to underline the main difference with atherosclerosis damage process in particularly during the calcification step.

Many studies in diverse models suggest that nitric oxide (NO) may be protective against liver injury due to ischaemia–reperfusion (IR). We evaluated, in an experimental in vivo model of rat liver partial ischaemia, the effects of pretreatment by an NO donor (spermineNONOate, 5 mg/kg), and exogenous cGMP (8Br-cGMP, 16 mg/kg) or an endogenous cGMP producer (ANP, 10 μg/kg), to assess their beneficial effects. After 6 h of reperfusion, 8Br-cGMP completely prevented the adverse effect of Nω-nitro- l -arginine (10 mg/kg) and 8Br-cGMP alone showed a protective action on both hepatocytes (AST, −25%, LDH, −55%) and endothelial cells (plasma hyaluronic acid (HA), −30%). ANP caused a marked decrease in AST and LDH activities only after 1 h of reperfusion (AST, −30%, LDH, −40%). Pretreatment with spermineNONOate prevented hepatocyte injury after 1 and 6 h of reperfusion (AST, −22%, LDH, −27%). However, neither spermineNONOate nor ANP had any protective effect on endothelial cell damage. These results confirm the beneficial effect of an NO donor and strongly suggest the implication of a cGMP pathway that does not involve a blockade of inflammatory cytokines production (IL-6 generation was unaffected by 8Br-cGMP pre-treatment). In our model, 8Br-cGMP showed a greater protective effect than ANP or spermineNONOate and so might be used to prevent hepatic injury after IR. Finally, we propose a schematic representation of the different routes for the actions of NO in protecting the liver against IR damage.