M1 and M2 macrophage proteolytic and angiogenic profile analysis in atherosclerotic patients reveals a distinctive profile in type 2 diabetes.

This study aimed to investigate atherosclerotic mediators' expression levels in M1 and M2 macrophages and to focus on the influence of diabetes on M1/M2 profiles. Macrophages from 36 atherosclerotic patients (19 diabetics and 17 non-diabetics) were cultured with interleukin-1ß (IL-1ß) or IL-4 to induce M1 or M2 phenotype, respectively. The atherosclerotic mediators' expression was evaluated by quantitative reverse transcription-polymerase chain reaction (RT-PCR). The results showed that M1 and M2 macrophages differentially expressed mediators involved in proteolysis and angiogenesis processes. The proteolytic balance (matrix metalloproteinase-9 (MMP-9)/tissue inhibitor of metalloproteinase-1 (TIMP-1), MMP-9/plasminogen activator inhibitor-1 (PAI-1) and MMP-9/tissue factor pathway inhibitor-2 (TFPI-2) ratios) was higher in M1 versus M2, whereas M2 macrophages presented higher angiogenesis properties (increased vascular endothelial growth factor/TFPI-2 and tissue factor/TFPI-2 ratios). Moreover, M1 macrophages from diabetics displayed more important proangiogenic and proteolytic activities than non-diabetics. This study reveals that M1 and M2 macrophages could differentially modulate major atherosclerosis-related pathological processes. Moreover, M1 macrophages from diabetics display a deleterious phenotype that could explain the higher plaque vulnerability observed in these subjects.

Von Willebrand factor as a biological sensor of blood flow to monitor percutaneous aortic valve interventions.

RATIONALE: Percutaneous aortic valve procedures are a major breakthrough in the management of patients with aortic stenosis. Residual gradient and residual aortic regurgitation are major predictors of midterm and long-term outcome after percutaneous aortic valve procedures. We hypothesized that (1) induction/recovery of high molecular weight (HMW) multimers of von Willebrand factor defect could be instantaneous after acute changes in blood flow, (2) a bedside point-of-care assay (platelet function analyzer-closure time adenine DI-phosphate [PFA-CADP]), reflecting HMW multimers changes, could be used to monitor in real-time percutaneous aortic valve procedures. OBJECTIVE: To investigate the time course of HMW multimers changes in models and patients with instantaneous induction/reversal of pathological high shear and its related bedside assessment. METHODS AND RESULTS: We investigated the time course of the induction/recovery of HMW multimers defects under instantaneous changes in shear stress in an aortic stenosis rabbit model and in patients undergoing implantation of a continuous flow left ventricular assist device. We further investigated the recovery of HMW multimers and monitored these changes with PFA-CADP in aortic stenosis patients undergoing transcatheter aortic valve implantation or balloon valvuloplasty. Experiments in the aortic stenosis rabbit model and in left ventricular assist device patients demonstrated that induction/recovery of HMW multimers occurs within 5 minutes. Transcatheter aortic valve implantation patients experienced an acute decrease in shear stress and a recovery of HMW multimers within minutes of implantation which was sustained overtime. In patients with residual high shear or with residual aortic regurgitation, no recovery of HMW multimers was observed. PFA-CADP profiles mimicked HMW multimers recovery both in transcatheter aortic valve implantation patients without aortic regurgitation (correction) and transcatheter aortic valve implantation patients with aortic regurgitation or balloon valvuloplasty patients (no correction). CONCLUSIONS: These results demonstrate that variations in von Willebrand factor multimeric pattern are highly dynamic, occurring within minutes after changes in blood flow. It also demonstrates that PFA-CADP can evaluate in real time the results of transcatheter aortic valve procedures.

Successful orthotopic transplantation of short tracheal segments without immunosuppressive therapy.

OBJECTIVES: Results of tracheal transplantation have been disappointing due to of ischaemia and rejection. It has been experimentally demonstrated that results of tracheal autograft/allograft transplantation were correlated with both graft length and revascularization method. Recently, we demonstrated that heterotopic epithelium-denuded-cryopreserved tracheal allograft (TA) displayed satisfactory immune tolerance. We aimed at evaluating the results of such allografts in orthotopic transplantation according to graft length and prior heterotopic or single-stage orthotopic revascularization in a rabbit model. METHODS: Twenty New Zealand rabbits were used. Six females served as donors. Tracheal mucosa was mechanically peeled off and then the TAs were cryopreserved. Male recipients were divided into three groups receiving: (i) long TA segment with prior heterotopic revascularization (10-12 tracheal rings, n = 3); (ii) average TA segment with single-stage orthotopic revascularization (6-8 tracheal rings, n = 4); (iii) short TA segment with single-stage orthotopic revascularization (4-5 tracheal rings, n = 7). No immunosuppressive therapy was administered. Grafts were assessed bronchoscopically and upon death or sacrifice by macroscopic evaluation, histology and immunohistochemical staining for apoptosis. RESULTS: Four animals were sacrificed from Day 33 to Day 220. The survival time of other recipients was 0-47 days (mean 19.6 ± 16.7 days). Aside from three animals that died from complications, all TA segments had satisfactory stiffness, were well vascularized, showed varying levels of neoangiogenesis and inflammatory infiltration devoid of lymphocytes, and showed evidence of only low levels of apoptosis. Varying degrees of fibroblastic proliferation originating from the lamina propria were observed in the lumen of all TAs and evolved over time into collagenized fibrosis in animals surviving over 45 days. Likewise, cartilage tracheal rings exhibited central calcification deposits, which started on Day 16 and increased over time. Epithelial regeneration was constantly observed. Intense fibroblastic proliferation led to stenosis in all animals from Groups (i) and (ii) but only one of seven animals from Group (iii). CONCLUSIONS: Our results suggest that short segments of epithelium-denuded-cryopreserved TA may be reliable for tracheal transplantation in the rabbit model without problems related to graft stiffness or immune rejection. Before considering clinical applications, investigations should be conducted in larger mammals.

Alterations in neutrophil production and function at an early stage in the high-fructose rat model of metabolic syndrome.

BACKGROUND: Although neutrophils are crucially involved in inflammation, they have received only little attention in metabolic syndrome (MetS). We hypothesized that neutrophil infiltration into adipose tissue (AT) may occur at an early stage of MetS, in association with modulation of major functions of neutrophils and of their bone marrow production. METHODS: Fifty-six male Sprague-Dawley rats were fed regular (control rats (CRs)) or high-fructose (60%; fructose-fed rats (FFRs)) diets. After 6 weeks, metabolic parameters were measured. Distribution of neutrophils into AT was investigated by immunohistochemistry. Function of circulating neutrophils (activation, reactive oxygen species production, phagocytosis, and apoptosis) was determined by flow cytometry. Granulopoiesis was evaluated by measuring the number and survival characteristics of neutrophil progenitors using bone marrow culture assays and flow cytometry. RESULTS: Compared with the CR group, the FFR group developed MetS (i.e., arterial hypertension, hypertriglyceridemia, fasting hyperglycemia, and greater intra-abdominal AT volume) and presented higher neutrophil infiltration into AT. At resting state, no significant difference for circulating neutrophil functions was observed between the 2 groups. In contrast, circulating neutrophils from the FFR group exhibited higher responses to phorbol-12-myristate-13-acetate for all studied functions, compared with the CR group, suggesting that early MetS induces neutrophil priming. In parallel, a diminished clonal capacity and an increased apoptosis in bone marrow-derived granulocyte progenitors and neutrophil precursors were observed in the FFR group compared with the CR group. CONCLUSIONS: These results provide evidence of an increased infiltration into intra-abdominal AT and modified production, function, and phenotype of neutrophils at an early stage of high-fructose diet-induced MetS.

Immune tolerance of epithelium-denuded-cryopreserved tracheal allograft.

OBJECTIVES: Animal and clinical studies have demonstrated the feasibility of tracheal allograft transplantation after a revascularization period in heterotopy, thus requiring immunosuppressive therapy. Given the key role of the respiratory epithelium in the immune rejection, we investigated the consequence of both epithelium denudation and cryopreservation in immune tolerance of tracheal allograft in a novel rabbit model. METHODS: Five adult female New Zealand rabbits served as donors of tracheas that were denuded of their epithelium and then cryopreserved, and 13 males were used as recipients. Following graft wrap using a lateral thoracic fascial flap, allograft segments 20 mm in length with (n = 9) or without (n = 4) insertion of an endoluminal tube were implanted under the skin of the chest wall. The animals did not receive any immunosuppressive drugs. Sacrifices were scheduled up to 91 days. Macroscopic and microscopic examinations and detection of apoptotic cells by immunohistochemical staining (Apostain) were used to study the morphology, stiffness, viability and immune rejection of allografts. RESULTS: There were no postoperative complications. Grafted composite allografts displayed satisfactory tubular morphology provided that an endoluminal tube was inserted. All rabbits were found to have an effective revascularization of their allograft and a mild non-specific inflammatory infiltrate with no significant lymphocyte infiltration. Cartilage rings showed early central calcification deposit, which increased over time, ensuring graft stiffness. Apoptosis events observed into the allograft cells were suggestive of minimal chronic rejection. CONCLUSIONS: Our results demonstrated that the epithelium-denuded-cryopreserved tracheal allograft implanted in heterotopy displayed satisfactory morphology, stiffness and immune tolerance despite the absence of immunosuppressive drugs. This allograft with a fascial flap transferable to the neck should be investigated in the setting of tracheal replacement in rabbits. Similar studies need to be conducted in bigger mammals before considering clinical applications.

Liver X receptor activation stimulates iron export in human alternative macrophages.

RATIONALE: In atherosclerotic plaques, iron preferentially accumulates in macrophages where it can exert pro-oxidant activities. OBJECTIVE: The objective of this study was, first, to better characterize the iron distribution and metabolism in macrophage subpopulations in human atherosclerotic plaques and, second, to determine whether iron homeostasis is under the control of nuclear receptors, such as the liver X receptors (LXRs). METHODS AND RESULTS: Here we report that iron depots accumulate in human atherosclerotic plaque areas enriched in CD68 and mannose receptor (MR)-positive (CD68(+)MR(+)) alternative M2 macrophages. In vitro IL-4 polarization of human monocytes into M2 macrophages also resulted in a gene expression profile and phenotype favoring iron accumulation. However, M2 macrophages on iron exposure acquire a phenotype favoring iron release, through a strong increase in ferroportin expression, illustrated by a more avid oxidation of extracellular low-density lipoprotein by iron-loaded M2 macrophages. In line, in human atherosclerotic plaques, CD68(+)MR(+) macrophages accumulate oxidized lipids, which activate LXRα and LXRß, resulting in the induction of ABCA1, ABCG1, and apolipoprotein E expression. Moreover, in iron-loaded M2 macrophages, LXR activation induces nuclear factor erythroid 2-like 2 expression, thereby increasing ferroportin expression, which, together with a decrease of hepcidin mRNA levels, promotes iron export. CONCLUSIONS: These data identify a role for M2 macrophages in iron handling, a process regulated by LXR activation.

Identification of additional proteins in differential proteomics using protein interaction networks.

In this study, we developed a novel computational approach based on protein-protein interaction networks to identify a list of proteins that might have remained undetected in differential proteomic profiling experiments. We tested our computational approach on two sets of human smooth muscle cell protein extracts that were affected differently by DNase I treatment. Differential proteomic analysis by saturation DIGE resulted in the identification of 41 human proteins. The application of our approach to these 41 input proteins consisted of four steps: (i) Compilation of a human protein-protein interaction network from public databases; (ii) calculation of interaction scores based on functional similarity; (iii) determination of a set of candidate proteins that are needed to efficiently and confidently connect the 41 input proteins; and (iv) ranking of the resulting 25 candidate proteins. Two of the three highest-ranked proteins, beta-arrestin 1, and beta-arrestin 2, were experimentally tested, revealing that their abundance levels in human smooth muscle cell samples were indeed affected by DNase I treatment. These proteins had not been detected during the experimental proteomic analysis. Our study suggests that our computational approach may represent a simple, universal, and cost-effective means to identify additional proteins that remain elusive for current 2D gel-based proteomic profiling techniques.

Tracheal reconstruction with a composite graft: fascial flap-wrapped allogenic aorta with external cartilage-ring support.

OBJECTIVES: Animal and clinical studies have demonstrated the feasibility of tracheal replacement by silicone-stented allogenic aortas. In clinical trials, however, this graft did not show mature cartilage regeneration into the grafts as was observed in animal models. To solve this issue, we investigated tracheal replacement with a composite graft based on a fascial flap-wrapped allogenic aorta with external cartilage-ring support in a rabbit model. METHODS: Seven male 'Géant des Flandres' and 'New Zealand' rabbits served as donors of aortas and cartilage rings, respectively. Nineteen female 'New Zealand' rabbits were used as recipients. First, in nine animals, neoangiogenesis of the composite graft following a wrap using a pedicled lateral thoracic fascial flap and implantation under the skin of the chest wall was investigated. Animal sacrifice was scheduled at regular intervals up to 38 days. Second, 10 animals underwent tracheal replacement with the composite graft after a 7-to-9 day revascularization period, and were followed-up to death. Macroscopic and microscopic examinations were used to study the morphology, stiffness and viability of the construct. RESULTS: There was one operative death after tracheal replacement. The first group of animals was found to have a satisfactory tubular morphology and stiffness of their construct associated with preserved histological structure of cartilages and moderate to severe aortic ischaemic lesions. In the group of rabbits having undergone tracheal replacement, the anatomical results were characterized by a discrepancy between the severity of ischaemic lesions involving both allogenic aorta and cartilage rings and the satisfactory biomechanical characteristics of the graft in 7 of 10 animals, probably due to cartilage calcification deposits associated with inflammatory scar tissue ensuring the stiffness of the construct. CONCLUSIONS: Our investigations demonstrate the feasibility of the replacement of circumferential tracheal defects using our composite graft. Future experiments using therapeutic bronchoscopy tools are required to draw conclusions regarding the effectiveness of this tracheal substitute in the long-term.

Aldosterone, mortality, and acute ischaemic events in coronary artery disease patients outside the setting of acute myocardial infarction or heart failure.

BACKGROUND: Recent studies have demonstrated that aldosterone levels measured in patients with heart failure or acute myocardial infarction (MI) are associated with long-term mortality, but the association with aldosterone levels in patients with coronary artery disease (CAD) outside these specific settings remains unknown. In addition, no clear mechanism has been elucidated to explain these observations. The present study was designed to evaluate the relationship between the level of aldosterone and the risk of death and acute ischaemic events in CAD patients with a preserved left ventricular (LV) function and no acute MI. METHODS AND RESULTS: In 799 consecutive CAD patients referred for elective coronary angioplasty measurements were obtained before the procedure for: aldosterone (median = 25 pg/mL), brain natriuretic peptide (BNP) (median = 35 pg/mL), hsC-reactive protein (median = 4.17 mg/L), and left ventricular ejection fraction (mean = 58%). Patients with acute MI or coronary syndrome (ACS) who required urgent revascularization were not included in the study. The primary endpoint, cardiovascular death, occurred in 41 patients during a median follow-up period of 14.9 months. Secondary endpoints-total mortality, acute ischaemic events (acute MI or ischaemic stroke), and the composite of death and acute ischaemic events-were observed in 52, 54, and 94 patients, respectively. Plasma aldosterone was found to be related to BMI, hypertension and NYHA class, and inversely related to age, creatinine clearance, and use of beta-blockers. Multivariate Cox model analysis demonstrated that aldosterone was independently associated with cardiovascular mortality (P = 0.001), total mortality (P = 0.001), acute ischaemic events (P = 0.01), and the composite of death and acute ischaemic events (P = 0.004). Reclassification analysis, using integrated discrimination improvement (IDI) and net reclassification improvement (NRI), demonstrated incremental predictive value of aldosterone (P < 0.0001). CONCLUSION: Our results demonstrate that, in patients with CAD but without heart failure or acute MI, the level of aldosterone is strongly and independently associated with mortality and the occurrence of acute ischaemic events.

Prognostic value of hemoglobin decline over the GRACE score in patients hospitalized for an acute coronary syndrome.

In this work, we analyzed the prognostic significance of changes in hemoglobin during intensive care unit (ICU) stay in patients with acute coronary syndromes (ACS). We prospectively enrolled 591 patients (62 ± 14 years old, 73% male, 48% ST elevated myocardial infarction) free of blood cell transfusion or bleeding events. Changes in hemoglobin between admission and ICU discharge were obtained. The primary endpoint was death or hospitalization for MI within 6 months. Hemoglobin decreased from 13.65 ± 1.77 to 13.17 ± 1.74 g/dl, p < 0.0001 in the whole population. The end point was reached in 43 patients at a mean follow-up of 180 (range 2-180 days). A decrease in hemoglobin ≥0.9 g/dl (32% of the population) was associated with adverse clinical outcomes (HR 2.37, 95% CI (1.30-4.35), p = 0.005, respectively). In multivariate analysis, age >77 year-old (p = 0.0016), Killip class ≥2 (p = 0.009), anemia (p = 0.0064), decreased estimated glomerular filtration rate (p = 0.003), and hemoglobin decline ≥0.9 g/dl (p < 0.0001) were independently associated with outcome. Hemoglobin decline and anemia both provided additional prognostic information on top of the GRACE score, as demonstrated by a systematic improvement in model global fit, discrimination, and calibration. Hemoglobin decline is frequent during ICU stay in non-bleeding ACS patients. A decline in hemoglobin ≥0.9 g/dl identifies high-risk patients. Identification of these patients refines the prognostic value of the GRACE score.

Quantitative mass spectrometry analysis using PAcIFIC for the identification of plasma diagnostic biomarkers for abdominal aortic aneurysm.

BACKGROUND: Abdominal aortic aneurysm (AAA) is characterized by increased aortic vessel wall diameter (>1.5 times normal) and loss of parallelism. This disease is responsible for 1-4% mortality occurring on rupture in males older than 65 years. Due to its asymptomatic nature, proteomic techniques were used to search for diagnostic biomarkers that might allow surgical intervention under nonlife threatening conditions. METHODOLOGY/PRINCIPAL FINDINGS: Pooled human plasma samples of 17 AAA and 17 control patients were depleted of the most abundant proteins and compared using a data-independent shotgun proteomic strategy, Precursor Acquisition Independent From Ion Count (PAcIFIC), combined with spectral counting and isobaric tandem mass tags. Both quantitative methods collectively identified 80 proteins as statistically differentially abundant between AAA and control patients. Among differentially abundant proteins, a subgroup of 19 was selected according to Gene Ontology classification and implication in AAA for verification by Western blot (WB) in the same 34 individual plasma samples that comprised the pools. From the 19 proteins, 12 were detected by WB. Five of them were verified to be differentially up-regulated in individual plasma of AAA patients: adiponectin, extracellular superoxide dismutase, protein AMBP, kallistatin and carboxypeptidase B2. CONCLUSIONS/SIGNIFICANCE: Plasma depletion of high abundance proteins combined with quantitative PAcIFIC analysis offered an efficient and sensitive tool for the screening of new potential biomarkers of AAA. However, WB analysis to verify the 19 PAcIFIC identified proteins of interest proved inconclusive save for five proteins. We discuss these five in terms of their potential relevance as biological markers for use in AAA screening of population at risk.

Measuring and targeting aldosterone and renin in atherosclerosis-a review of clinical data.

Our understanding of the development and progression of atherosclerosis has increased substantially over the past decades. A significant role for the renin-angiotensin-aldosterone system (RAAS) in this process has gained appreciation in recent years. Preclinical and clinical studies have associated components of the RAAS with various cardiovascular disease conditions. Classically known for its contribution to hypertension, dysregulation of the system is now also believed to promote vascular inflammation, fibrosis, remodeling, and endothelial dysfunction, all intimately related to atherosclerosis. The reduction in cardiovascular mortality and morbidity, as seen with the use of angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, supports the concept that RAAS is involved in the pathogenesis of atherosclerotic disease. However, the underlying molecular mechanisms of the pathophysiology remain to be completely understood. Evidence points toward additional benefit from therapeutic approaches aiming at more complete inhibition of the system and the possible utility of renin or aldosterone in the prediction of cardiovascular outcome. This review will summarize the current knowledge from clinical studies regarding the presumptive role of renin and aldosterone in the prediction and management of patients with atherosclerosis. For this purpose, a literature search was performed, focusing on available clinical data regarding renin or aldosterone and cardiovascular outcome.

Clinical and echocardiographic correlates of plasma B-type natriuretic peptide levels in patients with aortic valve stenosis and normal left ventricular ejection fraction.

BACKGROUND: Several studies suggest that BNP testing may help define the timing of aortic valve surgery in patients with aortic valve stenosis (AVS) prior onset of overt LV systolic dysfunction. The aim of this study was to identify clinical and echocardiographic correlates of plasma BNP levels in a large cohort of patients with AVS and preserved LV ejection fraction. METHOD AND RESULTS: One hundred thirty-five consecutive patients were prospectively included in the present study (Mean age 73 ± 13 years old, 66 (49%) male). Eighty-nine patients (66%) had severe AVS (aortic valve area <0.6 cm(2) /m(2) BSA). Plasma BNP levels, clinical and comprehensive Doppler echocardiography evaluation was performed in all patients. Independent clinical correlates of plasma BNP levels (R(2) = 0.19) were older age (P < 0.0001) and presence of AVS symptoms (P = 0.004). Independent echocardiographic correlates of plasma BNP levels (R(2) = 0.38) were E/Ea ratio (P = 0.01), LV mass index (P = 0.018), left atrial surface (P < 0.0001) and systolic pulmonary artery pressure (sPAP; P = 0.004). Overall, independent correlates of plasma BNP levels (R(2) = 0.47) were older age (P = 0.001), known coronary artery disease (P = 0.047), increased LV mass index (P = 0.001), left atrial enlargement (P = 0.002), and increased sPAP (P = 0.003). CONCLUSIONS: In patients with AVS and normal LV ejection fraction, plasma BNP predominantly reflects the clinical and echocardiographic consequences of afterload burden imposed on the left ventricle rather than the severity of valve stenosis, per se.

High-dose tranexamic acid reduces blood loss in postpartum haemorrhage.

INTRODUCTION: Our purpose in conducting this study was to determine whether administration of high-dose tranexamic acid (TA) at the time of diagnosis of postpartum haemorrhage (PPH) could reduce blood loss. METHODS: This was a randomised, controlled, multicentred, open-label trial. Women with PPH >800 mL following vaginal delivery were randomly assigned to receive TA (loading dose 4 g over 1 hour, then infusion of 1 g/hour over 6 hours) or not. In both groups, packed red blood cells (PRBCs) and colloids could be used according to French guidelines. The use of additional procoagulant treatments was permitted only in cases involving intractable bleeding. The primary objective was to assess the efficacy of TA in the reduction of blood loss in women with PPH, and the secondary objectives were the effect of TA on PPH duration, anaemia, transfusion and the need for invasive procedures. RESULTS: A total of 144 women fully completed the protocol (72 in each group). Blood loss between enrolment and 6 hours later was significantly lower in the TA group than in the control group (median, 173 mL; first to third quartiles, 59 to 377) than in controls (221 mL; first to third quartiles 105 to 564) (P = 0.041). In the TA group, bleeding duration was shorter and progression to severe PPH and PRBC transfusion was less frequent than in controls (P < 0.03). Invasive procedures were performed in four women in the TA group and in seven controls (P = NS). PPH stopped after only uterotonics and PRBC transfusion in 93% of women in the TA group versus 79% of controls (P = 0.016). Mild, transient adverse manifestations occurred more often in the TA group than in the control group (P = 0.03). CONCLUSIONS: This study is the first to demonstrate that high-dose TA can reduce blood loss and maternal morbidity in women with PPH. Although the study was not adequately powered to address safety issues, the observed side effects were mild and transient. A larger international study is needed to investigate whether TA can decrease the need for invasive procedures and reduce maternal morbidity in women with PPH. TRIAL REGISTRATION: Controlled Trials ISRCTN09968140.

Renal resistance index and its prognostic significance in patients with heart failure with preserved ejection fraction.

BACKGROUND: Functional renal impairment is a common feature of heart failure with preserved ejection fraction (HFpEF). The link between functional renal impairment and HFpEF remains incompletely understood. With hypertension and diabetes as frequent co-morbidities, patients with HFpEF are at risk of developing intra-renal vascular hemodynamic alterations that may lead to functional renal impairment and impact on prognosis. METHODS: Renal resistive index (RRI) was non-invasively determined by Doppler ultrasonic examination in 90 HFpEF patients and 90 age- and sex-matched hypertensive patients without evidence of heart failure (HF) who served as controls. Clinical, laboratory and cardiac echocardiography data were obtained in HFpEF patients and controls. To investigate its possible clinical relevance, RRI was evaluated as a prognostic index of all-cause mortality and hospitalization for HF. RESULTS: Mean RRI was substantially greater in HFpEF patients than in controls (P < 0.0001), while mean blood pressure, glomerular filtration rate, hemoglobin and serum protein levels were significantly lower in HFpEF patients than in controls. On multivariable analysis, mean RRI was independently associated with HFpEF. In addition, increased mean RRI was an independent predictor of poor outcome [hazard ratio = 1.06 95% confidence interval (1.01-1.10), P = 0.007] and remained significantly associated with the outcome after adjustment for univariate predictors that included low mean blood pressure, low hemoglobin concentration and low glomerular filtration rate. Conclusion. Patients with HFpEF exhibit intra-renal vascular hemodynamic alterations. The severity of intra-renal vascular hemodynamic alterations correlates with a poor outcome.

Human atherosclerotic plaque alternative macrophages display low cholesterol handling but high phagocytosis because of distinct activities of the PPARγ and LXRα pathways.

RATIONALE: A crucial step in atherogenesis is the infiltration of the subendothelial space of large arteries by monocytes where they differentiate into macrophages and transform into lipid-loaded foam cells. Macrophages are heterogeneous cells that adapt their response to environmental cytokines. Th1 cytokines promote monocyte differentiation into M1 macrophages, whereas Th2 cytokines trigger an "alternative" M2 phenotype. OBJECTIVE: We previously reported the presence of CD68(+) mannose receptor (MR)(+) M2 macrophages in human atherosclerotic plaques. However, the function of these plaque CD68(+)MR(+) macrophages is still unknown. METHODS AND RESULTS: Histological analysis revealed that CD68(+)MR(+) macrophages locate far from the lipid core of the plaque and contain smaller lipid droplets compared to CD68(+)MR(-) macrophages. Interleukin (IL)-4-polarized CD68(+)MR(+) macrophages display a reduced capacity to handle and efflux cellular cholesterol because of low expression levels of the nuclear receptor liver x receptor (LXR)α and its target genes, ABCA1 and apolipoprotein E, attributable to the high 15-lipoxygenase activity in CD68(+)MR(+) macrophages. By contrast, CD68(+)MR(+) macrophages highly express opsonins and receptors involved in phagocytosis, resulting in high phagocytic activity. In M2 macrophages, peroxisome proliferator-activated receptor (PPAR)γ activation enhances the phagocytic but not the cholesterol trafficking pathways. CONCLUSIONS: These data identify a distinct macrophage subpopulation with a low susceptibility to become foam cells but high phagocytic activity resulting from different regulatory activities of the PPARγ-LXRα pathways.

The presence of apoptotic bone marrow cells impairs the efficacy of cardiac cell therapy.

Injection of autologous bone marrow cells into infarcted myocardium has been proposed to limit the deterioration of cardiac function following myocardial infarction (MI); unfortunately, the beneficial effects observed have been modest. One of the limiting factors is believed to be poor local survival of the injected cells, but the potential impact of apoptosis among the injected cells has yet to be assessed. Therefore, this study aimed to quantify the apoptosis rate in bone marrow mononuclear cells (BMMCs) prepared for cardiac therapy, and to analyze their effects in vitro on cardiomyoblast apoptosis and in vivo on cardiac function recovery following MI. Using rabbit BMMCs prepared by Ficoll gradient, apoptotic cells were detected via Annexin V (AnV) staining. The effects of depleting the apoptotic cell population by means of AnV magnetic beads was tested in vitro after coculture with cardiomyoblasts (H9c2 cells) and in vivo after cell injection into the infarcted area. Left ventricular ejection fraction and scar extent were assessed by echography and histology 2 months later. After Ficoll gradient isolation, 37.3% (33.4-37.9%) of BMMCs were found to be apoptotic (Apo(Base) BMMCs). AnV depletion decreased the proportion of apoptotic cells to 20% (17.6-32%) (Apo(Low) BMMCs). Rabbits treated in vivo with Apo(Low) BMMCs after MI presented with significantly improved left ventricular ejection fraction [41.4% (41.0-43.6%) vs. 34.6% (34.6-35.9%), p = 0.03), reduced scar extent [20.4% (17.9-24.3%) vs. 25.6% (17.9-27.9%), p = 0.057], and reduced rate of cardiomyocyte apoptosis compared to those treated with Apo(Base) BMMCs. H9c2 apoptosis was found to be higher after coculture with Apo(Base) than with Apo(Low) BMMCs [25.6% (22.6-29.6%) vs. 10.1% (6.6-12.6%), p = 0.03], a result partially reproduced by cocultures with microparticle-rich supernatants from BMMCs. The presence of apoptotic cells among BMMCs impairs the efficacy of cardiac cell therapy after MI, an effect possibly mediated by apoptotic microparticles.