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BackgroundIn rodents, the stimulation of adrenal progesterone is necessary for renal adaptation under potassium depletion. Here, we sought to determine the role of progesterone in adrenal adaptation in potassium-depleted healthy human volunteers and compared our findings with data collected in patients with Gitelman syndrome (GS), a salt-losing tubulopathy.MethodsTwelve healthy young men were given a potassium-depleted diet for 7 days at a tertiary referral medical centre (NCT02297048). We measured by liquid chromatography coupled to tandem mass spectroscopy plasma steroid concentrations at Days 0 and 7 before and 30 min after treatment with tetracosactide. We compared these data with data collected in 10 GS patients submitted to tetracosactide test.ResultsThe potassium-depleted diet decreased plasma potassium in healthy subjects by 0.3 ± 0.1 mmol/L, decreased plasma aldosterone concentration by 50% (P = 0.0332) and increased plasma 17-hydroxypregnenolone concentration by 45% (P = 0.0232) without affecting other steroids. CYP17 activity, as assessed by 17-hydroxypregnenolone/pregnenolone ratio, increased by 60% (P = 0.0389). As compared with healthy subjects, GS patients had 3-fold higher plasma concentrations of aldosterone, 11-deoxycortisol (+30%) and delta 4-androstenedione (+14%). Their post-tetracosactide progesterone concentration was 2-fold higher than that of healthy subjects and better correlated to plasma potassium than to plasma renin.ConclusionThe increase in 17-hydroxypregnenolone concentration after mild potassium depletion in otherwise healthy human subjects suggests that 17 hydroxylation of pregnenolone prevents the increase in progesterone observed in potassium-depleted mice. The unexpected over-response of non-mineralocorticoid steroids to tetracosactide in GS subjects suggests that the adrenal system not only adapts to sodium depletion but may also respond to hypokalaemia.

Objectives Pericardial effusion is common after cardiac surgery. Growing evidence suggests that colchicine may be useful for acute pericarditis, but its efficacy in reducing pericardial effusion volume postoperatively has not been assessed. Methods This randomised, double-blind, placebo-controlled study conducted in 10 centres in France included 197 patients at high risk of tamponade (ie, with moderate to large-sized persistent effusion (echocardiography grades 2, 3 or 4 on a scale of 0–4)) at 7–30 days after cardiac surgery. Patients were randomly assigned to receive colchicine, 1 mg daily (n=98), or a matching placebo (n=99). The main end point was change in pericardial effusion grade after 14-day treatment. Secondary end points included frequency of late cardiac tamponade. Results The placebo and the colchicine groups showed a similar mean baseline pericardial effusion grade (2.9±0.8 vs 3.0±0.8) and similar mean decrease from baseline after treatment (−1.1±1.3 vs −1.3±1.3 grades). The mean difference in grade decrease between groups was −0.19 (95% CI −0.55 to 0.16, p=0.23). In total, 13 cases of cardiac tamponade occurred during the 14-day treatment (7 and 6 in the placebo and colchicine groups, respectively; p=0.80). At 6-month follow-up, all patients were alive and had undergone a total of 22 (11%) drainages: 14 in the placebo group and 8 in the colchicine group (p=0.20). Conclusions In patients with pericardial effusion after cardiac surgery, colchicine administration does not reduce the effusion volume or prevent late cardiac tamponade. Clinical trial reg No NCT01266694.

Although subthalamic stimulation is a recognised treatment for motor complications in Parkinson's disease, reports on behavioural outcomes are controversial, which represents a major challenge when counselling candidates for subthalamic stimulation. We aimed to assess changes in behaviour in patients with Parkinson's disease receiving combined treatment with subthalamic stimulation and medical therapy over a 2-year follow-up period as compared with the behavioural evolution under medical therapy alone.We did a parallel, open-label study (EARLYSTIM) at 17 surgical centres in France (n=8) and Germany (n=9). We recruited patients with Parkinson's disease who were disabled by early motor complications. Participants were randomly allocated (1:1) to either medical therapy alone or bilateral subthalamic stimulation plus medical therapy. The primary outcome was mean change in quality of life from baseline to 2 years. A secondary analysis was also done to assess behavioural outcomes. We used the Ardouin Scale of Behavior in Parkinson's Disease to assess changes in behaviour between baseline and 2-year follow-up. Apathy was also measured using the Starkstein Apathy Scale, and depression was assessed with the Beck Depression Inventory. The secondary analysis was done in all patients recruited. We used a generalised estimating equations (GEE) regression model for individual items and mixed model regression for subscores of the Ardouin scale and the apathy and depression scales. This trial is registered with ClinicalTrials.gov, number NCT00354133. The primary analysis has been reported elsewhere; this report presents the secondary analysis only.Between July, 2006, and November, 2009, 251 participants were recruited, of whom 127 were allocated medical therapy alone and 124 were assigned bilateral subthalamic stimulation plus medical therapy. At 2-year follow-up, the levodopa-equivalent dose was reduced by 39% (-363·3 mg/day [SE 41·8]) in individuals allocated bilateral subthalamic stimulation plus medical therapy and was increased by 21% (245·8 mg/day [40·4]) in those assigned medical therapy alone (p0·0001). Neuropsychiatric fluctuations decreased with bilateral subthalamic stimulation plus medical therapy during 2-year follow-up (mean change -0·65 points [SE 0·15]) and did not change with medical therapy alone (-0·02 points [0·15]); the between-group difference in change from baseline was significant (p=0·0028). At 2 years, the Ardouin scale subscore for hyperdopaminergic behavioural disorders had decreased with bilateral subthalamic stimulation plus medical therapy (mean change -1·26 points [SE 0·35]) and had increased with medical therapy alone (1·12 points [0·35]); the between-group difference was significant (p0·0001). Mean change from baseline at 2 years in the Ardouin scale subscore for hypodopaminergic behavioural disorders, the Starkstein Apathy Scale score, and the Beck Depression Inventory score did not differ between treatment groups. Antidepressants were stopped in 12 patients assigned bilateral subthalamic stimulation plus medical therapy versus four patients allocated medical therapy alone. Neuroleptics were started in nine patients assigned medical therapy alone versus one patient allocated bilateral subthalamic stimulation plus medical therapy. During the 2-year follow-up, two individuals assigned bilateral subthalamic stimulation plus medical therapy and one patient allocated medical therapy alone died by suicide.In a large cohort with Parkinson's disease and early motor complications, better overall behavioural outcomes were noted with bilateral subthalamic stimulation plus medical therapy compared with medical therapy alone. The presence of hyperdopaminergic behaviours and neuropsychiatric fluctuations can be judged additional arguments in favour of subthalamic stimulation if surgery is considered for disabling motor complications.German Federal Ministry of Education and Research, French Programme Hospitalier de Recherche Clinique National, and Medtronic.

Background Patients with a left ventricular ejection fraction (LVEF) of less than 40 % are at high risk of developing postoperative low cardiac output syndrome (LCOS). Despite actual treatments (inotropic agents and/or mechanical assist devices), the mortality rate of such patients remains very high (13 to 24 %). The LICORN trial aims at assessing the efficacy of a preoperative infusion of levosimendan in reducing postoperative LCOS in patients with poor LVEF undergoing coronary artery bypass grafting (CABG). Methods/Design LICORN study is a multicenter, randomized double-blind, placebo-controlled trial in parallel groups. 340 patients with LVEF ≤40 %, undergoing CABG will be recruited from 13 French hospitals. The study drug will be started after anaesthesia induction and infused over 24 h (0.1 μg/kg/min). The primary outcome (postoperative LCOS) is evaluated using a composite criterion composed of: 1) need for inotropic agents beyond 24 h following discontinuation of the study drug; 2) need for post-operative mechanical assist devices or failure to wean from these techniques when inserted pre-operatively; 3) need for renal replacement therapy. Secondary outcomes include: 1) mortality at Day 28 and Day 180; 2) each item of the composite criterion of the primary outcome; 3) the number of “ventilator-free” days and “out of intensive care unit” days at Day 28. Discussion The usefulness of levosimendan in the perioperative period has not yet been documented with a high level of evidence. The LICORN study is the first randomized controlled trial evaluating the clinical value of preoperative levosimendan in high risk cardiac surgical patients undergoing CABG. Trial registration number NCT02184819 (ClinicalTrials.gov).

CD36, a major adhesion molecule expressed by monocytes/macrophages, plays a key role in the binding and internalization of oxidized low-density lipoprotein (OxLDL). This adhesion molecule, a member of an important scavenger receptor family, contains a very short C-terminal cytoplasmic tail that is known to induce intracellular signalling events. However, the domains on the cytoplasmic tail involved in such signal transduction are unknown. In this study, we have investigated the functional components of the cytoplasmic tail by site-directed mutagenesis coupled with functional OxLDL and monoclonal antibody (mAb) binding studies. Seven truncated or punctual CD36 constructs, localized in the cytoplasmic tail, were produced by site-directed mutagenesis. Each construct was stably expressed in HEK293 cells. We used a quantitative and a qualitative method, labelling OxLDL with either iodine or rhodamine, to determine the functional importance of the cytoplasmic domains in OxLDL internalization. Results indicate that: (1) a deletion of the last amino-acid (construct K472STOP) significantly reduces, compared with wild-type, the binding, internalization and degradation of OxLDL; (2) truncation of the last six amino-acids (construct R467STOP) significantly reduces OxLDL binding; (3) the above two constructs (K472STOP and R467STOP) showed a reduced rate of OxLDL internalization compared with wild-type; (4) the binding and rate of internalization of an anti-CD36 monoclonal antibody (10/5) was not affected by the above mentioned mutants (K472STOP and R467STOP), compared with wild-type. This study shows, for the first time, a specific site on the CD36 cytoplasmic tail that is critical for the binding, endocytosis and targeting of OxLDL.

Regulation of the expression of platelet-activating factor (PAF) receptor by atherogenic lipoproteins might contribute to atherogenesis. We show that progressive oxidation of low-density lipoprotein (LDL) gradually inhibits PAF receptor expression on the macrophage cell surface. We tested the effect of oxidized LDL (oxLDL) on PAF receptor expression in human monocytes that do not contain peroxisome-proliferator-activated receptor γ (PPARγ), a nuclear receptor activated by oxLDL. OxLDL decreased by 50% (P ⩽0.001) and by 29% (P⩽0.05) the binding of PAF and the expression of PAF receptor mRNA respectively. Next we demonstrated that progressive oxidation of LDLs significantly activated PPARα-dependent transcription in transfected mouse aortic endothelial cells. Finally we demonstrated, in mature macrophages, that fenofibrate (20µM), a specific PPARα agonist, but not the specific PPARγ agonist BRL49653 (20nM), significantly decreased both PAF binding and PAF receptor mRNA expression, by 65% and 40% (P⩽0.001) respectively. Additionally, another PPARα agonist, Wy14,643, decreased PAF receptor promoter activity by 70% (P⩽0.05) in transfected THP-1 cells, suggesting the involvement of the proximal promoter region (-980 to -500) containing a series of four nuclear factor (NF)-κB motifs. Thus PPARα might be involved in the down-regulation of PAF receptor gene expression by oxLDLs in human monocytes/macrophages. The oxidation of one or more lipid components of LDLs might result in the formation of natural activators of PPARα. It is hypothesized that such activators might modulate inflammation and apoptosis upon atherogenesis by decreasing the expression of PAF receptor.

Abstract —Phospholipase A 2 s (PLA 2 s) constitute a family of enzymes that hydrolyze fatty acids of membrane phospholipids, thus initiating the synthesis of proinflammatory mediators. Various PLA 2 s have been detected in human atherosclerotic arteries (advanced lesions); however, only the secretory group of PLA 2 has been shown to specifically hydrolyze low density lipoprotein (LDL)–associated phospholipids and, as such, may play a potential role in atherogenesis. In the present study, we investigated the expression pattern of group IIa, IV, and V PLA 2 s in human macrophages, which are the key cells involved in the onset and perpetuation of atherosclerosis. Immunohistochemical staining by double labeling showed that the secretory nonpancreatic PLA 2 (snpPLA 2 ) is detectable in macrophages in the intima of early atherosclerotic lesions. Reverse transcription–polymerase chain reaction analysis of RNA extracted from human monocytes clearly showed that expression of group IV PLA 2 was enhanced during differentiation into macrophages, with an onset of induction at days 2 to 3 of differentiation. Group V snpPLA 2 was constitutively expressed on differentiation, whereas the detection of group IIa snpPLA 2 was dependent on both differentiation and subsequent stimulation of macrophages. Indeed, the transcription of group IIa snpPLA 2 in macrophages was induced by treatment with minimally modified or mildly oxidized LDL, whereas native, extensively oxidized, or acetylated LDL had no effect. To our knowledge, this is the first report describing induction of group IIa snpPLA 2 expression in human monocyte–derived macrophages. The mRNA levels of cytosolic PLA 2 group IV and snpPLA 2 group V remained unchanged on LDL treatment. Thus, our results show that the expression of distinct PLA 2 enzymes is regulated not only during differentiation of monocytes into macrophages but also on exposure of macrophages to distinct LDL species. Consequently, our results indicate a potential role for both cytosolic and secretory PLA 2 enzymes in inflammation and in macrophage functions related to atherosclerosis, with a specific role for group IIa snpPLA2 in LDL scavenging.

Monocytes/macrophages play a key role in atherogenesis due to their inflammatory properties including formation of lipid mediators such as platelet-activating-factor (PAF). We investigated the effect of oxidized low-density lipoprotein (oxLDL) on lipopolysaccharide (LPS)-induced PAF receptor (PAF-R) expression in human macrophages and the implication of the nuclear factor (NF)-kappaB in this regulation. LPS-treatment (1 microg.mL(-1)) of macrophages increased PAF binding and PAF-R mRNA expression by 56% (P < 0.05) and twofold (P < 0.01), respectively. In contrast, highly oxidized low-density lipoprotein [ox24hLDL; 100 microg.mL(-1); thiobarbituric acid reacting substances: 31 +/- 3 nmol equiv. malondialdehyde (MDA).mg protein LDL-1] diminished PAF-R expression (-69%; P < 0.05) and mRNA level (- 45%; P < 0.01). LPS pretreatment induced the activated form of p65 in the nuclear compartment of macrophages (detected by Western blotting) and NF-kappaB binding activity (by electrophoretic mobility shift assay). Treatment of macrophages with ox24hLDL suppressed the LPS-induced binding of NF-kappaB to DNA. In addition, treatment of macrophages with lysophosphatidylcholine (2 and 10 microM), a major component of oxLDL, inhibited the LPS-induced NF-kappaB binding to DNA and reduced PAF binding by 30 and 70%, respectively. In conclusion, oxLDL may downregulate PAF-R expression in human macrophages by inhibiting LPS-induced NF-kappaB binding to DNA.

Abstract —The regulation of macrophage lipoprotein lipase (LPL) secretion and mRNA expression by atherogenic lipoproteins is of critical relevance to foam cell formation. LPL is present in arterial lesions and constitutes a bridging ligand between lipoproteins, proteoglycans, and cell receptors, thus favoring macrophage lipoprotein uptake and lipid accumulation. We investigated the effects of native and of oxidized lipoproteins on the expression of LPL in an in vitro human monocyte-macrophage system. Exposure of mature macrophages (day 12) to highly copper-oxidized human low density lipoprotein (LDL) (100 μg protein per milliliter) led to marked reduction in the expression of LPL activity (−62%, P P P P 6-hour oxidation) exerts negative feedback on LPL secretion in human monocytes-macrophages via a reduction in mRNA levels. By contrast, native LDL and mildly oxidized LDL (

Abstract Human monocyte–derived macrophages play a major role in the initiation and progression of atherosclerotic lesions as a result of the production of a wide spectrum of proinflammatory and prothrombotic factors. Among such factors is a potent inflammatory phospholipid, platelet-activating factor (PAF), which is produced after macrophage activation. Because the cells involved in PAF biosynthesis are typically targets for the bioactions of PAF via specific cell surface receptors, we evaluated the expression of the PAF receptor in human monocyte–derived macrophages. Oxidized LDL (oxLDL) exerts multiple cellular effects that enhance lesion progression; we therefore investigated the potential modulation of expression of the macrophage PAF receptor by oxLDL. [ 3 H]PAF bound to adherent human macrophages with a K d of 2.1 nmol/L and a B max of 19 fmol/10 6 cells; ≈5300 binding sites per cell were detected. OxLDL (100 μg protein per milliliter) induced a twofold decrease in cellular PAF binding after 3 hours at 37°C. Analysis of macrophage mRNA by reverse transcription–polymerase chain reaction (RT-PCR) revealed two forms corresponding to the PAF receptor, of which the leukocyte type (type 1 promoter) predominated. Expression of PAF receptor mRNA, evaluated by quantitative RT-PCR using an actin or a GAPDH mimic, was progressively reduced (up to 70%) by oxLDL up to 6 hours and remained low for at least 24 hours. Such downregulation was reversible after incubation of the cells for 24 hours in oxLDL-free medium. Addition of forskolin (3 μmol/L) or dibutyryl cAMP (1 mmol/L) to macrophage cultures reproduced the oxLDL-mediated inhibition of PAF receptor expression; carbamyl PAF reduced PAF binding and PAF mRNA to a similar degree (≈50%). These data demonstrate that atherogenic oxLDL downregulates the expression of both cellular PAF receptors and PAF receptor mRNA in macrophages, consistent with both a diminished bioresponse to PAF and decreased cell motility. Such diminished bioresponse to a powerful antacoid reflects the suppression of an acute inflammatory reaction, thereby leading to chronic, low-level inflammation, such as that characteristic of fatty streaks and more advanced atherosclerotic plaques.

International audience; Importance: Low cardiac output syndrome after cardiac surgery is associated with high morbidity and mortality in patients with impaired left ventricular function.Objective: To assess the ability of preoperative levosimendan to prevent postoperative low cardiac output syndrome.Design, setting, and participants: Randomized, double-blind, placebo-controlled trial conducted in 13 French cardiac surgical centers. Patients with a left ventricular ejection fraction less than or equal to 40% and scheduled for isolated or combined coronary artery bypass grafting with cardiopulmonary bypass were enrolled from June 2013 until May 2015 and followed during 6 months (last follow-up, November 30, 2015).Interventions: Patients were assigned to a 24-hour infusion of levosimendan 0.1 µg/kg/min (n = 167) or placebo (n = 168) initiated after anesthetic induction.Main outcomes and measures: Composite end point reflecting low cardiac output syndrome with need for a catecholamine infusion 48 hours after study drug initiation, need for a left ventricular mechanical assist device or failure to wean from it at 96 hours after study drug initiation when the device was inserted preoperatively, or need for renal replacement therapy at any time postoperatively. It was hypothesized that levosimendan would reduce the incidence of this composite end point by 15% in comparison with placebo.Results: Among 336 randomized patients (mean age, 68 years; 16% women), 333 completed the trial. The primary end point occurred in 87 patients (52%) in the levosimendan group and 101 patients (61%) in the placebo group (absolute risk difference taking into account center effect, -7% [95% CI, -17% to 3%]; P = .15). Predefined subgroup analyses found no interaction with ejection fraction less than 30%, type of surgery, and preoperative use of β-blockers, intra-aortic balloon pump, or catecholamines. The prevalence of hypotension (57% vs 48%), atrial fibrillation (50% vs 40%), and other adverse events did not significantly differ between levosimendan and placebo.Conclusions and relevance: Among patients with low ejection fraction who were undergoing coronary artery bypass grafting with cardiopulmonary bypass, levosimendan compared with placebo did not result in a significant difference in the composite end point of prolonged catecholamine infusion, use of left ventricular mechanical assist device, or renal replacement therapy. These findings do not support the use of levosimendan for this indication.Trial registration: EudraCT Number: 2012-000232-25; clinicaltrials.gov Identifier: NCT02184819.