Apolipoprotein J protects cardiomyocytes from lipid-mediated inflammation and cytotoxicity induced by the epicardial adipose tissue of diabetic patients.

Diabetic patients present increased volume and functional alterations in epicardial adipose tissue (EAT). We aimed to analyze EAT from type 2 diabetic patients and the inflammatory and cytotoxic effects induced on cardiomyocytes. Furthermore, we analyzed the cardioprotective role of apolipoprotein J (apoJ). EAT explants were obtained from nondiabetic patients (ND), diabetic patients without coronary disease (DM), and DM patients with coronary disease (DM-C) after heart surgery. Morphological characteristics and gene expression were evaluated. Explants were cultured for 24 h and the content of nonesterified fatty acids (NEFA) and sphingolipid species in secretomes was evaluated by lipidomic analysis. Afterwards, secretomes were added to AC16 human cardiomyocytes for 24 h in the presence or absence of cardioprotective molecules (apoJ and HDL). Cytokine release and apoptosis/necrosis were assessed by ELISA and flow cytometry. The EAT from the diabetic samples showed altered expression of genes related to lipid accumulation, insulin resistance, and inflammation. The secretomes from the DM samples presented an increased ratio of pro/antiatherogenic ceramide (Cer) species, while those from DM-C contained the highest concentration of saturated NEFA. DM and DM-C secretomes promoted inflammation and cytotoxicity on AC16 cardiomyocytes. Exogenous Cer16:0, Cer24:1, and palmitic acid reproduced deleterious effects in AC16 cells. These effects were attenuated by exogenous apoJ. Diabetic secretomes promoted inflammation and cytotoxicity in cardiomyocytes. This effect was exacerbated in the secretomes of the DM-C samples. The increased content of specific NEFA and ceramide species seems to play a key role in inducing such deleterious effects, which are attenuated by apoJ.

Weight loss benefits on HDL cholesterol persist even after weight regaining.

BACKGROUND: Obesity-related comorbidities may relapse in patients with weight regain after bariatric surgery. However, HDL cholesterol (HDLc) levels increase after surgery and seem to remain stable despite a gradual increase in BMI. The aim of this study is to analyze the effects of weight regain after bariatric surgery on HDL cholesterol. MATERIALS AND METHODS: This is a retrospective, observational, cohort study in patients who underwent bariatric surgery in the Hospital de la Santa Creu i Sant Pau (Barcelona) between 2007 and 2015. Patients without at least 5 years of follow-up after surgery, under fibrate treatment, and those who required revisional surgery were excluded from the analysis. Data were collected at baseline, 3 and 6 months after surgery, and then annually until 5 years post-surgery. RESULTS: One hundred fifty patients were analyzed. 93.3% of patients reached > 20% of total weight loss after surgery. At 5th year, 37% of patients had regained > 15% of nadir weight, 60% had regained > 10%, and 22% had regained < 5% of nadir weight. No differences were found in HDLc levels between the different groups of weight regain, nor in the % of change in HDLc levels between nadir weight and 5 years, or in the proportion of patients with normal HDLc concentrations either. CONCLUSION: HDLc remains stable regardless of weight regain after bariatric surgery.

PCSK9 plasma concentration is associated with epicardial adipose tissue volume and metabolic control in patients with type 1 diabetes.

Patients with type 1 diabetes (T1D) have a greater risk of cardiovascular disease. Proconvertase subtilisin-kexin 9 (PCSK9) is involved in the atherosclerosis process. This study aimed to determine the relationship between PCSK9 levels and epicardial adipose tissue (EAT) volume and cardiometabolic variables in patients with T1D. This was an observational cross-sectional study including 73 patients with T1D. Clinical, biochemical and imaging data were collected. We divided the patients into two groups according to their glycemic control and the EAT index (iEAT) percentile. We performed a correlation analysis between the collected variables and PCSK9 levels; subsequently, we performed a multiple regression analysis with the significant parameters. The mean age was 47.6 ± 8.5 years, 58.9% were men, and the BMI was 26.9 ± 4.6 kg/m2. A total of 31.5%, 49.3% and 34.2% of patients had hypertension, dyslipidemia and smoking habit, respectively. The PCSK9 concentration was 0.37 ± 0.12 mg/L, which was greater in patients with worse glycemic control (HbA1c > 7.5%), dyslipidemia and high EAT volume (iEAT > 75th percentile). The PCSK9 concentration was positively correlated with age (r = 0.259; p = 0.027), HbA1c (r = 0.300; p = 0.011), insulin dose (r = 0.275; p = 0.020), VLDL-C level (r = 0.331; p = 0.004), TG level (r = 0.328; p = 0.005), and iEAT (r = 0.438; p < 0.001). Multiple regression analysis revealed that 25% of the PCSK9 variability was explained by iEAT and HbA1c (p < 0.05). The PCSK9 concentration is associated with metabolic syndrome parameters, poor glycemic control and increased EAT volume in patients with T1D.

LDL binding to cell receptors and extracellular matrix is proatherogenic in obesity but improves after bariatric surgery.

Obesity is a major global public health issue involving dyslipidemia, oxidative stress, inflammation, and increased risk of CVD. Weight loss reduces this risk, but the biochemical underpinnings are unclear. We explored how obesity and weight loss after bariatric surgery influence LDL interactions that trigger proatherogenic versus antiatherogenic processes. LDL was isolated from plasma of six patients with severe obesity before (basal) and 6-12 months after bariatric surgery (basal BMI = 42.7 kg/m2; 6-months and 12-months postoperative BMI = 34.1 and 30 kg/m2). Control LDL were from six healthy subjects (BMI = 22.6 kg/m2). LDL binding was quantified by ELISA; LDL size and charge were assessed by chromatography; LDL biochemical composition was determined. Compared to controls, basal LDL showed decreased nonatherogenic binding to LDL receptor, which improved postoperatively. Conversely, basal LDL showed increased binding to scavenger receptors LOX1 and CD36 and to glycosaminoglycans, fibronectin and collagen, which is proatherogenic. One year postoperatively, this binding decreased but remained elevated, consistent with elevated lipid peroxidation. Serum amyloid A and nonesterified fatty acids were elevated in basal and postoperative LDL, indicating obesity-associated inflammation. Aggregated and electronegative LDL remained elevated, suggesting proatherogenic processes. These results suggest that obesity-induced inflammation contributes to harmful LDL alterations that probably increase the risk of CVD. We conclude that in obesity, LDL interactions with cell receptors and extracellular matrix shift in a proatherogenic manner but are partially reversed upon postoperative weight loss. These results help explain why the risk of CVD increases in obesity but decreases upon weight loss.

Increased sLRP1 and decreased atrial natriuretic peptide plasma levels in newly diagnosed T2DM patients are normalized after optimization of glycemic control.

Background: Low-density lipoprotein receptor-related protein 1 (LRP1) negatively modulates circulating atrial natriuretic peptide (ANP) levels. Both molecules are involved in the regulation of cardiometabolism. Objectives: To evaluate soluble LRP1 (sLRP1) and ANP levels in people with newly diagnosed type 2 diabetes mellitus (T2DM) and determine the effects of metabolic optimization. Methods: This single-center longitudinal observational study recruited patients with newly diagnosed T2DM (n = 29, HbA1c > 8.5%), and 12 healthy control, age- and sex-matched volunteers. sLRP1 and ANP levels were measured by immunoassays at T2DM onset and at one year after optimization of glycemic control (HbA1c ≤ 6.5%). Results: T2DM had higher sLRP1 levels than the control group (p = 0.014) and lower ANP levels (p =0.002). At 12 months, 23 T2DM patients reached the target of HbA1c ≤ 6.5%. These patients significantly reduced sLRP1 and increased ANP levels. Patients who did not achieve HbA1c < 6.5% failed to normalize sLRP1 and ANP levels. There was an inverse correlation in the changes in sLRP1 and ANP (p = 0.031). The extent of sLRP1 changes over 12 months of metabolic control positively correlated with those of total cholesterol, LDL cholesterol, TG, TG/HDLc, and apolipoprotein B. Conclusions: Newly diagnosed T2DM patients have an increased sLRP1/ANP ratio, and increased sLRP1 and decreased ANP levels are normalized in the T2DM patients that reached an strict glycemic and metabolic control. sLRP1/ANP ratio could be a reliable marker of cardiometabolic function.

Special Issue: New Insight into the Molecular Role of Lipids and Lipoproteins in Vascular Diseases.

Lipids and lipoproteins play a key role in cardiovascular diseases (CVD), mainly in the development of atherosclerosis [...].

Association of candidate genetic variants and circulating levels of ApoE/ApoJ with common neuroimaging features of cerebral amyloid angiopathy.

Introduction: Cerebral amyloid angiopathy (CAA) is characterized by the accumulation of amyloid-ß (Aß) in brain vessels and is a main cause of lobar intracerebral hemorrhage (ICH) in the elderly. CAA is associated with magnetic resonance imaging (MRI) markers of small vessel disease (SVD). Since Aß is also accumulated in Alzheimer's disease (AD) in the brain parenchyma, we aimed to study if several single nucleotide polymorphisms (SNPs) previously associated with AD were also associated with CAA pathology. Furthermore, we also studied the influence of APOE and CLU genetic variants in apolipoprotein E (ApoE) and clusterin/apolipoprotein J (ApoJ) circulating levels and their distribution among lipoproteins. Methods: The study was carried out in a multicentric cohort of 126 patients with lobar ICH and clinical suspicion of CAA. Results: We observed several SNPs associated with CAA neuroimaging MRI markers [cortical superficial siderosis (cSS), enlarged perivascular spaces in the centrum semiovale (CSO-EPVS), lobar cerebral microbleeds (CMB), white matter hyperintensities (WMH), corticosubcortical atrophy and CAA-SVD burden score]. Concretely, ABCA7 (rs3764650), CLU (rs9331896 and rs933188), EPHA1 (rs11767557), and TREML2 (rs3747742) were significantly associated with a CAA-SVD burden score. Regarding circulating levels of apolipoproteins, protective AD SNPs of CLU [rs11136000 (T) and rs9331896 (C)] were significantly associated with higher HDL ApoJ content in the lobar ICH cohort. APOEε2 carriers presented higher plasma and LDL-associated ApoE levels whereas APOEε4 carriers presented lower plasma ApoE levels. Additionally, we observed that lower circulating ApoJ and ApoE levels were significantly associated with CAA-related MRI markers. More specifically, lower LDL-associated ApoJ and plasma and HDL-associated ApoE levels were significantly associated with CSO-EPVS, lower ApoJ content in HDL with brain atrophy and lower ApoE content in LDL with the extent of cSS. Discussion: This study reinforces the relevance of lipid metabolism in CAA and cerebrovascular functionality. We propose that ApoJ and ApoE distribution among lipoproteins may be associated with pathological features related to CAA with higher ApoE and ApoJ levels in HDL possibly enhancing atheroprotective, antioxidative, and anti-inflammatory responses in cerebral ß-amyloidosis.

Can Electronegative LDL Act as a Multienzymatic Complex?

Electronegative LDL (LDL(-)) is a minor form of LDL present in blood for which proportions are increased in pathologies with increased cardiovascular risk. In vitro studies have shown that LDL(-) presents pro-atherogenic properties, including a high susceptibility to aggregation, the ability to induce inflammation and apoptosis, and increased binding to arterial proteoglycans; however, it also shows some anti-atherogenic properties, which suggest a role in controlling the atherosclerotic process. One of the distinctive features of LDL(-) is that it has enzymatic activities with the ability to degrade different lipids. For example, LDL(-) transports platelet-activating factor acetylhydrolase (PAF-AH), which degrades oxidized phospholipids. In addition, two other enzymatic activities are exhibited by LDL(-). The first is type C phospholipase activity, which degrades both lysophosphatidylcholine (LysoPLC-like activity) and sphingomyelin (SMase-like activity). The second is ceramidase activity (CDase-like). Based on the complementarity of the products and substrates of these different activities, this review speculates on the possibility that LDL(-) may act as a sort of multienzymatic complex in which these enzymatic activities exert a concerted action. We hypothesize that LysoPLC/SMase and CDase activities could be generated by conformational changes in apoB-100 and that both activities occur in proximity to PAF-AH, making it feasible to discern a coordinated action among them.

Circulating lipoprotein-carried miRNome analysis reveals novel VLDL-enriched microRNAs that strongly correlate with the HDL-microRNA profile.

Lipoproteins have been described as microRNAs (miRNAs) carriers. Unfortunately, the bibliography on this topic is scarce and shows a high variability between independent investigations. In addition, the miRNA profiles of the LDL and VLDL fractions have not been completely elucidated. Here, we profiled the human circulating lipoprotein-carried miRNome. Lipoprotein fractions (VLDL, LDL and HDL) were isolated from the serum of healthy subjects by ultracentrifugation and purified by size-exclusion chromatography. A panel of 179 miRNAs commonly expressed in circulation was evaluated in the lipoprotein fractions using quantitative real-time PCR (qPCR) assays. A total of 14, 4 and 24 miRNAs were stably detected in the VLDL, LDL and HDL fractions, respectively. VLDL- and HDL-miRNA signatures were highly correlated (rho 0.814), and miR-16-5p, miR-142-3p, miR-223-3p and miR-451a were among the top 5 expressed miRNAs in both fractions. miR-125a-5p, miR-335-3p and miR-1260a, were detected in all lipoprotein fractions. miR-107 and miR-221-3p were uniquely detected in the VLDL fraction. HDL showed the larger number of specifically detected miRNAs (n = 13). Enrichment in specific miRNA families and genomic clusters was observed for HDL-miRNAs. Two sequence motifs were also detected for this group of miRNAs. Functional enrichment analysis including the miRNA signatures from each lipoprotein fraction suggested a potential role in mechanistic pathways previously associated with cardiovascular disease: fibrosis, senescence, inflammation, immune response, angiogenesis, and cardiomyopathy. Collectively, our results not only support the role of lipoproteins as circulating miRNA carriers but also describe for the first time the role of VLDL as a miRNA transporter.

Soluble low-density lipoprotein receptor-related protein 1 as a surrogate marker of carotid plaque inflammation assessed by 18F-FDG PET in patients with a recent ischemic stroke.

BACKGROUND: 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) identifies carotid plaque inflammation and predicts stroke recurrence. AIM: Our aim was to evaluate the performance of soluble low-density lipoprotein receptor-related protein 1 (sLRP1) as an indicator of carotid plaque inflammation. METHODS: A prospective study was conducted among adult patients with recent (< 7 days) anterior circulation ischemic stroke and at least one atherosclerotic plaque in the ipsilateral internal carotid artery. Patients underwent an early (< 15 days from inclusion) 18F-FDG PET, and the maximum standardized uptake value (SUVmax) within the plaque was measured. sLRP1 levels were measured in plasma samples by ELISA. The association of sLRP1 with SUVmax was assessed using bivariate and multivariable linear regression analyses. Hazard ratios (HR) were estimated with Cox regression to evaluate the association between circulating sLRP1 and stroke recurrence. RESULTS: The study was conducted with 64 participants, of which 57.8% had ≥ 50% carotid stenosis. The multivariable linear and logistic regression analyses showed that sLRP1 was independently associated with (i) SUVmax within the plaque (ß = 0.159, 95% CI 0.062-0.257, p = 0.002) and (ii) a probability of presenting SUVmax ≥ 2.85 g/mL (OR = 1.31, 95% CI 1.00-1.01, p = 0.046), respectively. Participants with stroke recurrence showed higher sLRP1 levels at baseline [6447 ng/mL (4897-11163) vs. 3713 ng/mL (2793-4730); p = 0.018]. CONCLUSIONS: sLRP1 was independently associated with carotid plaque inflammation as measured by 18F-FDG PET in patients with recent ischemic stroke and carotid atherosclerosis.

Electronegative LDL Is Associated with Plaque Vulnerability in Patients with Ischemic Stroke and Carotid Atherosclerosis.

Owing to the high risk of recurrence, identifying indicators of carotid plaque vulnerability in atherothrombotic ischemic stroke is essential. In this study, we aimed to identify modified LDLs and antioxidant enzymes associated with plaque vulnerability in plasma from patients with a recent ischemic stroke and carotid atherosclerosis. Patients underwent an ultrasound, a CT-angiography, and an 18F-FDG PET. A blood sample was obtained from patients (n = 64, 57.8% with stenosis ≥50%) and healthy controls (n = 24). Compared to the controls, patients showed lower levels of total cholesterol, LDL cholesterol, HDL cholesterol, apolipoprotein B (apoB), apoA-I, apoA-II, and apoE, and higher levels of apoJ. Patients showed lower platelet-activating factor acetylhydrolase (PAF-AH) and paraoxonase-1 (PON-1) enzymatic activities in HDL, and higher plasma levels of oxidized LDL (oxLDL) and electronegative LDL (LDL(-)). The only difference between patients with stenosis ≥50% and <50% was the proportion of LDL(-). In a multivariable logistic regression analysis, the levels of LDL(-), but not of oxLDL, were independently associated with the degree of carotid stenosis (OR: 5.40, CI: 1.15-25.44, p < 0.033), the presence of hypoechoic plaque (OR: 7.52, CI: 1.26-44.83, p < 0.027), and of diffuse neovessels (OR: 10.77, CI: 1.21-95.93, p < 0.033), indicating that an increased proportion of LDL(-) is associated with vulnerable atherosclerotic plaque.

Type 2 Diabetes mellitus alters the cargo of (poly)phenol metabolome and the oxidative status in circulating lipoproteins.

The incidence of diabetes on the worldwide population has tripled in the past 5 decades. While drug-based therapies are valuable strategies to treat and ease the socio-economic burden of diabetes, nutritional strategies offer valuable alternatives to prevent and manage diabetes onset and contribute to the sustainability of health budgets. Whilst, intervention studies have shown that (poly)phenol-rich diets improve fasting glucose levels and other blood parameters, very little is known about the distribution of ingested polyphenols in circulation and the impact of diabetes on its cargo. In this study we investigate the impact of type 2 diabetes on the cargo of plasma (poly)phenols. Our results show that phenolic compounds are heterogeneously distributed in circulation though mainly transported by lipoprotein populations. We also found that diabetes has a marked effect on the phenolic content transported by VLDL resulting in the decrease in the content of flavonoids and consequently a decrease in the antioxidant capacity. In addition to the reduced bioavailability of (poly)phenol metabolites and increase of oxidative status in LDL and HDL populations in diabetes, cell-based assays show that sub-micromolar amounts of microbial (poly)phenol metabolites are able to counteract the pro-inflammatory status in glucose-challenged endothelial cells. Our findings highlight the relevance of triglyceride-rich lipoproteins in the transport and delivery of bioactive plant-based compounds to the endothelium in T2DM supporting the adoption of nutritional guidelines as an alternative strategy to drug-based therapeutic approaches.

Divergent Effects of Glycemic Control and Bariatric Surgery on Circulating Concentrations of TMAO in Newly Diagnosed T2D Patients and Morbidly Obese.

High circulating concentrations of the gut microbiota-derived metabolite trimethylamine N-oxide (TMAO) are significantly associated with the risk of obesity and type 2 diabetes (T2D). We aimed at evaluating the impact of glycemic control and bariatric surgery on circulating concentrations of TMAO and its microbiota-dependent intermediate, γ-butyrobetaine (γBB), in newly diagnosed T2D patients and morbidly obese subjects following a within-subject design. Based on HbA1c concentrations, T2D patients achieved glycemic control. However, the plasma TMAO and γBB concentrations were significantly increased, without changes in estimated glomerular filtration rate. Bariatric surgery was very effective in reducing weight in obese subjects. Nevertheless, the surgery reduced plasma γBB concentrations without affecting TMAO concentrations and the estimated glomerular filtration rate. Considering these results, an additional experiment was carried out in male C57BL/6J mice fed a Western-type diet for twelve weeks. Neither diet-induced obesity nor insulin resistance were associated with circulating TMAO and γBB concentrations in these genetically defined mice strains. Our findings do not support that glycemic control or bariatric surgery improve the circulating concentrations of TMAO in newly diagnosed T2D and morbidly obese patients.

Obesity Surgery Improves Hypogonadism and Sexual Function in Men without Effects in Sperm Quality.

(1) Background: Obesity is associated with hypogonadism, sexual dysfunction, and impaired fertility in men. However, its effects on semen parameters or sexual function remain debatable. (2) Methods: This paper involves a longitudinal study in men submitted for obesity surgery at a university tertiary hospital. Patients were studied at baseline and at 6, 12, and 18 months after obesity surgery. At each visit, anthropometry measures were collected and hormonal and semen parameters were studied. Sexual function was evaluated with the International Index of Erectile Function (IIEF). (3) Results: A total of 12 patients were included. The average body mass index of patients decreased from 42.37 ± 4.44 to 29.6 ± 3.77 kg/m2 at 18 months after surgery (p < 0.05). Hormonal parameters improved after obesity surgery. The proportion of sperm cells with normal morphology tended to decrease from baseline and became most significant at 18 months (5.83 ± 4.50 vs. 2.82 ± 2.08). No significant changes were found in the remaining semen parameters. Erectile function improved significantly at six months after surgery. (4) Conclusions: The authors believe that, in general, the effects of obesity surgery on fertility may be limited or even deleterious (at least in the short and midterm follow-up).

Atherogenicity of low-density lipoproteins after switching from a protease inhibitor to dolutegravir: a substudy of the NEAT022 study.

BACKGROUND: The aim of this study was to investigate whether switching from a ritonavir-boosted PI-based regimen to a dolutegravir-based regimen improved the atherogenic properties of LDL particles in patients with HIV. METHODS: This was a substudy of the NEAT022 study (ClinicalTrials.gov NCT02098837). Adults with HIV with a Framingham score >10% or aged >50 years and being treated with a stable boosted PI-based regimen were randomized to either switch to dolutegravir or continue with boosted PI. At baseline and Week 48, we assessed atherogenic LDL properties: LDL particle size and phenotype (A, intermediate, B), oxidized LDL (ox-LDL) and lipoprotein-associated phospholipase A2 (Lp-PLA2) activity. RESULTS: Eighty-six participants (dolutegravir 44; PI 42) were included. Participants had a median (IQR) age of 54 (51-57) years and 79.1% were male. In the dolutegravir arm, after 48 weeks, we observed: (1) an increase in LDL size [median 1.65 Š(IQR -0.60 to 4.20); P = 0.007], correlated with the decrease in triglyceride concentration [Spearman correlation = -0.352 (P = 0.001)], with a corresponding decrease of subjects with atherogenic LDL phenotype B (36.4% to 20.5%; P = 0.039); (2) a decrease in Lp-PLA2 activity [median 1.39 µmol/min/mL (IQR -2.3 to 0.54); P = 0.002]; and (3) a decrease in ox-LDL [median 14 U/L (IQR -102 to 13); P = 0.006]. In the PI arm, none of these favourable lipid modifications was observed. CONCLUSIONS: Forty-eight weeks after switching from a PI-based to a dolutegravir-based regimen, patients with Framingham score >10% or aged >50 years showed improvement of several atherogenic lipid features, including LDL particle phenotype, ox-LDL and Lp-PLA2.

Plasma sICAM-1 as a Biomarker of Carotid Plaque Inflammation in Patients with a Recent Ischemic Stroke.

18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) identifies carotid plaque inflammation and predicts stroke recurrence in patients with atherothrombotic stroke. The aim of the study was to identify plasma inflammatory biomarkers associated with plaque inflammation according to 18F-FDG uptake. We conducted a prospective study of consecutive adult patients with a recent (< 7 days) anterior circulation ischemic stroke and at least one atherosclerotic plaque in the ipsilateral internal carotid artery. We included 64 patients, 57.8% of whom showed a carotid stenosis ≥ 50%. All patients underwent an early (< 15 days from inclusion) 18F-FDG PET, and a blood sample was obtained at days 7 ± 1 from the stroke. The plasma concentration of 16 inflammation-related molecules was analyzed in a Luminex using xMAP technology. Multivariable linear regression was used to assess the association between plasma biomarkers and the standardized uptake value (SUV) of 18F-FDG uptake. Soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular adhesion molecule-1 (sVCAM-1), and fractalkine (FKN) were independently associated with plaque inflammation (ß = 0.121, 95% CI 0.061-0.181, p < 0.001; ß = 0.144, 95% CI 0.012-0.276, p = 0.033; ß = 0.136, 95% CI 0.037-0.235, p = 0.008). In a multivariable logistic regression analysis, sICAM-1 was associated with SUVmax ≥ 2.85 (OR = 1.02, 95% CI 1.00-1.03, p = 0.020). Multivariable Cox regression was used to assess the association between biomarkers and stroke recurrence. sICAM-1 was associated with stroke recurrence (HR = 1.03, 95% CI 1.00-1.05, p = 0.002). In summary, elevated concentrations of sICAM-1 were associated with carotid plaque inflammation and an increased risk of stroke recurrence in patients with recent ischemic stroke and carotid atherosclerosis.

Assessment of Ex Vivo Antioxidative Potential of Murine HDL in Atherosclerosis.

This chapter provides details on a simple and reproducible method used to determine the capacity of murine HDL to prevent the oxidation of LDL . The principle of the method is based on the rearrangement of double bonds of polyunsaturated fatty acids that occurs during the oxidation of human LDL , which generates a sigmoidal curve. The shape and length of the curve is modified in the presence of HDL , and such modifications are easily quantifiable by measuring the absorbance of conjugated dienes at 234 nm. The general technique described herein may be applied to evaluate the effect of HDL obtained from different experimental murine models of atherosclerosis.

Monitoring Atheroprotective Macrophage Cholesterol Efflux In Vivo.

This chapter provides details on the methodologies currently used to monitor macrophage cholesterol efflux in vivo in mice. The general principles and techniques described herein can be applied to evaluate the effect of different experimental pathophysiological conditions or the efficacy of different therapeutic strategies on the modulation of in vivo cholesterol efflux to plasma acceptors and the rate of reverse transport of unesterified cholesterol from macrophages to feces in mice.