The protection of ischemic myocardium: applications in human medicine and experimental prospects

Acute myocardial infarction (AMI) is a serious condition, associated with a high mortality rate in western countries. The emergence of revascularisation techniques for occluded arteries has improved the prognosis considerably, but the time to revascularisation remains critical. New cardioprotective strategies were therefore needed to further improve myocardial salvage. These strategies were for a long time based on meeting the myocardium’s demand in oxygen. In recent years however, new substances were developed to oppose directly the cell disorders associated with ischemia-reperfusion, or to induce an endogenous adaptation of the myocardium through preconditioning. Another approach includes reducing the body temperature during the ischemic process to delay infarct extension.L'infarctus du myocarde est une affection grave, à l'origine d'une mortalité élevée dans les pays occidentaux. L'émergence des techniques de revascularisation des artères occluses a permis d'améliorer considérablement le pronostic de cette affection mais les délais de revascularisation restent incompressibles. Le développement de stratégies cardioprotectrices additionnelles était donc nécessaire. Ces stratégies ont pendant longtemps reposé sur la nécessité de satisfaire les besoins en oxygène du myocarde. Plus récemment, des substances ont été développées dans le but de s'opposer directement aux désordres cellulaires liés à l'ischémie-reperfusion ou d'induire une adaptation endogène du myocarde par préconditionnement. Une autre approche consiste à réduire la température de l'organisme au cours du processus ischémique en vue de retarder l'extension de l'infarctus

Erythrocyte phospholipid and polyunsaturated fatty acid composition in diabetic retinopathy

Background: Long chain polyunsaturated fatty acids (LCPUFAs) including docosahexaenoic acid and arachidonic acid are suspected to play a key role in the pathogenesis of diabetes. LCPUFAs are known to be preferentially concentrated in specific phospholipids termed as plasmalogens. This study was aimed to highlight potential changes in the metabolism of phospholipids, and particularly plasmalogens, and LCPUFAs at various stages of diabetic retinopathy in humans. Methodology and Principal Findings: We performed lipidomic analyses on red blood cell membranes from controls and mainly type 2 diabetes mellitus patients with or without retinopathy. The fatty acid composition of erythrocytes was determined by gas chromatography and the phospholipid structure was determined by liquid chromatography equipped with an electrospray ionisation source and coupled with a tandem mass spectrometer (LC-ESI-MS/MS). A significant decrease in levels of docosahexaenoic acid and arachidonic acid in erythrocytes of diabetic patients with or without retinopathy was observed. The origin of this decrease was a loss of phosphatidyl-ethanolamine phospholipids esterified with these LCPUFAs. In diabetic patients without retinopathy, this change was balanced by an increase in the levels of several phosphatidyl-choline species. No influence of diabetes nor of diabetic retinopathy was observed on the concentrations of plasmalogen-type phospholipids. Conclusions and Significance: Diabetes and diabetic retinopathy were associated with a reduction of erythrocyte LCPUFAs in phosphatidyl-ethanolamines. The increase of the amounts of phosphatidyl-choline species in erythrocytes of diabetic patients without diabetic retinopathy might be a compensatory mechanism for the loss of LC-PUFA-rich phosphatidyl-ethanolamines

Anxiety and Depression Prevalence Rates in Age-Related Macular Degeneration

PURPOSE. To estimate the prevalence rates of depression and anxiety in patients with wet age-related macular degeneration (AMD) and the relationship with visual acuity and to develop a simple algorithm for depression screening. METHODS. This cross-sectional, prospective, observational, multicenter study was performed in France, Germany, and Italy. Retina specialists at 10 centers per country each enrolled 12 consecutive patients with wet ARMD. Patients were stratified into four severity groups by using best eye (BE) and worst eye (WE) visual acuity (VA) thresholds (BE:VA 20/40 and WE:VA 20/200). Patients rated themselves on the Hospital Anxiety and Depression Scale (HADS). Analysis of variance was performed to estimate the effect of VA severity levels on HADS scores adjusted on age, gender, and country. RESULTS. Patients (females 609/6) were recruited, with a mean age of 77 years and 2.3 years' disease duration. Mean BE:VA at inclusion was 0.49 logMar (logarithm of the minimum angled of resolution) and NW:VA 1.0 logMar. The prevalence of severe depression increased from 0% (BE:VA >= 20/40+WE:VA >= 20/200) to 7.6% (BE:VA < 20/40+)WE:VA < 20/200), whereas anxiety was unrelated to VA loss. Moreover, total depression scores were strongly associated with VA severity (P = 0.006), but not total anxiety scores (P = 0.840). Responses to two HADS items ("I still enjoy things I used to enjoy"; "I can enjoy a good book or radio or television program") identified 95% of severely to moderately depressed patients. CONCLUSIONS. Self-rated depression in patients with AMD was associated with VA severity level. It should, therefore, be relatively easy for ophthalmologists to implement the screening procedure and refer identified patients to psychiatrists for proper assessment and treatment

Differential antibacterial activity against Pseudomonas aeruginosa by carbon monoxide-releasing molecules.

International audienceAIMS: Carbon monoxide (CO) delivered in a controlled manner to cells and organisms mediates a variety of pharmacological effects to the extent that CO-releasing molecules (CO-RMs) are being developed for therapeutic purposes. Recently, ruthenium-based CO-RMs have been shown to posses important bactericidal activity. Here we assessed the effect of fast CO releasers containing ruthenium (Ru(CO)(3)Cl(glycinate) [CORM-3] and tricarbonyldichlororuthenium(II) dimer [CORM-2]) and a novel slow manganese-based CO releaser ([Me(4)N][Mn(CO)(4)(thioacetate)(2)] [CORM-371]) on O(2) consumption and growth of Pseudomonas aeruginosa (PAO1). We then compared these effects with the action elicited by sodium boranocarbonate (CORM-A1), which lacks a transition metal but liberates CO with a rate similar to CORM-371. RESULTS: CORM-2, CORM-3, and, to a lesser extent, CORM-371 exerted a significant bactericidal effect and decreased O(2) consumption in PAO1 in vitro. The effect appeared to be independent of reactive oxygen species production, but in the case of metal-containing compounds it was prevented by the thiol donor N-acetylcysteine. In contrast, CORM-A1 was bacteriostatic rather than bactericidal in vitro eliciting only a moderate and transient decrease in O(2) consumption. INNOVATION: None of the tested CO-RMs was toxic to murine macrophages or human fibroblasts at the concentration impairing PA01 growth but only ruthenium-containing CO-RMs showed potential therapeutic properties by increasing the survival of mice infected with PA01. CONCLUSION: CO carriers inhibit bacterial growth and O(2) consumption in vitro, but transition metal carbonyls appear more powerful than compounds spontaneously liberating CO. The nature of the metal in CO-RMs also modulates the anti-bacterial effect, with ruthenium-based CO-RMs being efficacious both in vitro and in vivo

A new HPLC-ESI-MS/MS method to characterize and quantify phosphatidyl-choline with VLC-PUFA: Application to human retina

Purpose: Mutations in the ELOVL4 gene have been found in Stargardt-like macular dystrophy or STD3. Previous studies have shown that ELOVL4 is involved in the biosynthesis of very long chain polyunsaturated fatty acids (VLC-PUFA). The aim of this work was to develop a HPLC-ESI-MS/MS method of characterization and quantification of dipolyunsaturated phosphatidyl-choline (PC) molecular species containing VLC-PUFA and to apply it on retinas from human donors. Methods: Eyeballs were collected from calf as well as from nine human donors (body donation to Science). The neural retina was dissected from the RPE/choroid. Following lipid extraction, phosphorus content of total phospholipids was determined.Using a triple quadrupole MS instrument, PC molecular species were structurally characterized by collision-induced dissociation in the negative mode with a method based on normal-HPLC-ESIMS/MS. PC molecular species were then quantified using precursor ion scanning of m/z 184amu in the positive mode. Results: The characterization of PC species was done on bovine retinas. Among them, 28 were dipolyunsaturated PC species containing one VLC-PUFA (C24 to C36) with three to six double bonds. VLC-PUFA were always in the sn-1 position whilst PUFA at the sn-2 position was exclusively docosahexaenoic acid (DHA, C22:6.n-3). Most of these VLC-PUFA-containing dipolyunsaturated PC were detected and quantified in human retinas. The main represented compounds were those having VLC-PUFA of 32 carbon atoms (C32:3, C32:4, C32:5 and C32:6) and 34 carbon atoms (C34:3, C34:4, C34:5 and C34:6). Dipolyunsaturated PC with 36:5 and 36:6 were detected in lower quantities. Conclusions: This new HPLC-ESI-MS/MS method is sensitive and specific enough to structurally characterize and quantify all molecular species of PC, including those esterified with VLC-PUFA. This technique is valuable for a precise characterization of PC containingVLC-PUFA in retina and may be useful for better understanding their implication in the pathogenesis of STD3

Evaluation of lung recovery after static administration of three different perfluorocarbons in pigs.

International audienceBackground: The respiratory properties of perfluorocarbons (PFC) have been widely studied for liquid ventilation inhumans and animals. Several PFC were tested but their tolerance may depend on the species. Here, the effects of asingle administration of liquid PFC into pig lungs were assessed and compared. Three different PFC having distinctevaporative and spreading coefficient properties were evaluated (Perfluorooctyl bromide [PFOB], perfluorodecalin[PFD] and perfluoro-N-octane [PFOC]).Methods: Pigs were anesthetized and submitted to mechanical ventilation. They randomly received an intra-trachealadministration of 15 ml/kg of either PFOB, PFD or PFOC with 12 h of mechanical ventilation before awakening andweaning from ventilation. A Control group was submitted to mechanical ventilation with no PFC administration. Allanimals were followed during 4 days after the initial PFC administration to investigate gas exchanges and clinicalrecovery. They were ultimately euthanized for histological analyses and assessment of PFC residual concentrationswithin the lungs using dual nuclei fluorine and hydrogen Magnetic Resonance Imaging (MRI). Sixteen animals wereincluded (4/group).Results: In the PFD group, animals tended to be hypoxemic after awakening. In PFOB and PFOC groups, blood gaseswere not significantly different from the Control group after awakening. The poor tolerance of PFD was likely related toa large amount of residual PFC, as observed using MRI in all lung samples (≈10% of lung volume). This percentage waslower in the PFOB group (≈1%) but remained significantly greater than in the Control group. In the PFOC group, thepercentage of residual PFC was not significantly different from that of the Control group (≈0.1%). Histologically, themost striking feature was an alveolar infiltration with foam macrophages, especially in the groups treated by PFD orPFOB.Conclusions: Of the three tested perfluorocarbons, PFOC offered the best tolerance in terms of lung function, gasexchanges and residuum in the lung. PFOC was rapidly cleared from the lungs and virtually disappeared after 4 dayswhereas PFOB persisted at significant levels and led to foam macrophage infiltration. PFOC could be relevant for shortterm total liquid ventilation with a rapid weaning

Lipid Composition of the Human Eye: Are Red Blood Cells a Good Mirror of Retinal and Optic Nerve Fatty Acids?

International audienceBACKGROUND: The assessment of blood lipids is very frequent in clinical research as it is assumed to reflect the lipid composition of peripheral tissues. Even well accepted such relationships have never been clearly established. This is particularly true in ophthalmology where the use of blood lipids has become very common following recent data linking lipid intake to ocular health and disease. In the present study, we wanted to determine in humans whether a lipidomic approach based on red blood cells could reveal associations between circulating and tissue lipid profiles. To check if the analytical sensitivity may be of importance in such analyses, we have used a double approach for lipidomics. METHODOLOGY AND PRINCIPAL FINDINGS: Red blood cells, retinas and optic nerves were collected from 9 human donors. The lipidomic analyses on tissues consisted in gas chromatography and liquid chromatography coupled to an electrospray ionization source-mass spectrometer (LC-ESI-MS). Gas chromatography did not reveal any relevant association between circulating and ocular fatty acids except for arachidonic acid whose circulating amounts were positively associated with its levels in the retina and in the optic nerve. In contrast, several significant associations emerged from LC-ESI-MS analyses. Particularly, lipid entities in red blood cells were positively or negatively associated with representative pools of retinal docosahexaenoic acid (DHA), retinal very-long chain polyunsaturated fatty acids (VLC-PUFA) or optic nerve plasmalogens. CONCLUSIONS AND SIGNIFICANCE: LC-ESI-MS is more appropriate than gas chromatography for lipidomics on red blood cells, and further extrapolation to ocular lipids. The several individual lipid species we have identified are good candidates to represent circulating biomarkers of ocular lipids. However, further investigation is needed before considering them as indexes of disease risk and before using them in clinical studies on optic nerve neuropathies or retinal diseases displaying photoreceptors degeneration