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TMAO, a metabolite of dietary choline, is considered a pro-atherogenic molecule for its ability to interfere with the reverse cholesterol transport, in which apolipoprotein A-I and HDL play a key role. In the present work it was evaluated how TMAO impacts on the development of atherosclerosis in mice with different levels of apoA-I/HDL. Mice deficient in both murine apoA-I and apoE (DKO) and DKO mice overexpressing human apoA-I (DKO/hA-I), characterized by extremely low or high plasma HDL levels respectively, were fed for 16 weeks two standard rodent diets, differing only in their choline content (0.09% or 1.2%). At the end of the dietary treatment, atherosclerosis development was quantified at the aortic sinus, targeted plasma metabolomics was performed, and gene expression was evaluated in liver, duodenum, jejunum and ileum. With both diets, DKO mice developed much larger plaques than DKO/hA-I mice. High-choline diet increased plasma TMAO levels in both genotypes. Interestingly, a worsening of plaque development by high choline diet occurred in DKO/hA-I mice only (0.057±0.048 mm2 vs 0.0988±0.064 mm2, p

Background: HDL (high-density lipoprotein) and its major protein component, apoA-I (apolipoprotein A-I), play a unique role in cholesterol homeostasis and immunity. ApoA-I deficiency in hyperlipidemic, atheroprone mice was shown to drive cholesterol accumulation and inflammatory cell activation/proliferation. The present study was aimed at investigating the impact of apoA-I deficiency on lipid deposition and local/systemic inflammation in normolipidemic conditions. Methods: ApoE deficient mice, apoE/apoA-I double deficient (DKO) mice, DKO mice overexpressing human apoA-I, and C57Bl/6J control mice were fed normal laboratory diet until 30 weeks of age. Plasma lipids were quantified, atherosclerosis development at the aortic sinus and coronary arteries was measured, skin ultrastructure was evaluated by electron microscopy. Blood and lymphoid organs were characterized through histological, immunocytofluorimetric, and whole transcriptome analyses. Results: DKO were characterized by almost complete HDL deficiency and by plasma total cholesterol levels comparable to control mice. Only DKO showed xanthoma formation and severe inflammation in the skin-draining lymph nodes, whose transcriptome analysis revealed a dramatic impairment in energy metabolism and fatty acid oxidation pathways. An increased presence of CD4 + T effector memory cells was detected in blood, spleen, and skin-draining lymph nodes of DKO. A worsening of atherosclerosis at the aortic sinus and coronary arteries was also observed in DKO versus apoE deficient. Human apoA-I overexpression in the DKO background was able to rescue the skin phenotype and halt atherosclerosis development. Conclusions: HDL deficiency, in the absence of hyperlipidemia, is associated with severe alterations of skin morphology, aortic and coronary atherosclerosis, local and systemic inflammation.

Background and purpose Fenretinide, a synthetic retinoid derivative first investigated for cancer prevention and treatment, has been shown to ameliorate glucose tolerance, improve plasma lipid profile and reduce body fat mass. These effects, together with its ability to inhibit ceramide synthesis, suggest that fenretinide may have an anti-atherosclerotic action. Experimental approach To this aim, nine-week-old apoE-knockout (EKO) female mice were fed for twelve weeks a Western diet, without (control) or with (0.1% w/w) fenretinide. As a reference, wild-type (WT) mice were treated similarly. Growth and metabolic parameters were monitored throughout the study. Atherosclerosis development was evaluated in the aorta and at the aortic sinus. Blood and lymphoid organs were further characterized with thorough cytological/histological and immunocytofluorimetric analyses. Key results Fenretinide treatment significantly lowered body weight, glucose levels and plasma levels of total cholesterol, triglycerides, and phospholipids. In the liver, fenretinide remarkably reduced hepatic glycogenosis and steatosis driven by the Western diet. Treated spleens were abnormally enlarged, with severe follicular atrophy and massive extramedullary haematopoiesis. Severe renal hemosiderin deposition was observed in treated EKO mice. Treatment resulted in a threefold increase of total leukocytes (WT and EKO) and raised the activated/resting monocyte ratio in EKO mice. Finally, atherosclerosis development was markedly increased at the aortic arch, thoracic and abdominal aorta of fenretinide-treated mice. Conclusions and implications We provide the first evidence that, despite beneficial metabolic effects, fenretinide treatment may enhance the development of atherosclerosis.

Among strategies to reduce the remaining risk of cardiovascular disease, interest has focused on using infusions of synthetic high-density lipoprotein (sHDL).New Zealand rabbits underwent a perivascular injury at both carotids and were randomly allocated into 2 protocols: (1) a single-dose study, where rabbits were treated with a single infusion of sHDL containing a trimeric form of human apoA-I (TN-sHDL, 200 mg/kg) or with Placebo; (2) a multiple-dose study, where 4 groups of rabbits were treated 5 times with Placebo or TN-sHDL at different doses (8, 40, 100 mg/kg). Plaque changes were analysed in vivo by intravascular ultrasound. Blood was drawn from rabbits for biochemical analyses and cholesterol efflux capacity evaluation.In both protocols, atheroma volume in the Placebo groups increased between the first and the second intravascular ultrasound evaluation. A stabilization or a slight regression was instead observed vs baseline in the TN-sHDL-treated groups (P0.005 vs Placebo after infusion). TN-sHDL treatment caused a sharp rise of plasma-free cholesterol levels and a significant increase of total cholesterol efflux capacity. Histologic analysis of carotid plaques showed a reduced macrophage accumulation in TN-sHDL-treated rabbits compared with Placebo (P0.05).Our results demonstrate that acute and subacute treatments with TN-sHDL are effective in stabilizing atherosclerotic plaques in a rabbit model. This effect appears to be related to a reduced intraplaque accumulation of inflammatory cells. Besides recent failures in proving its efficacy, sHDL treatment remains a fascinating therapeutic option for the reduction of cardiovascular risk.

Functional enrichment analysis is an analytical method to extract biological insights from gene expression data, popularized by the ever-growing application of high-throughput techniques. Typically, expression profiles are generated for hundreds to thousands of genes/proteins from samples belonging to two experimental groups, and after ad-hoc statistical tests, researchers are left with lists of statistically significant entities, possibly lacking any unifying biological theme. Functional enrichment tackles the problem of putting overall gene expression changes into a broader biological context, based on pre-existing knowledge bases of reference: database collections of known expression regulation, relationships and molecular interactions. STRING is among the most popular tools, providing both protein-protein interaction networks and functional enrichment analysis for any given set of identifiers. For complex experimental designs, manually retrieving, interpreting, analyzing and abridging functional enrichment results is a daunting task, usually performed by hand by the average wet-biology researcher. We have developed reString, a cross-platform software that seamlessly retrieves from STRING functional enrichments from multiple user-supplied gene sets, with just a few clicks, without any need for specific bioinformatics skills. Further, it aggregates all findings into human-readable table summaries, with a built-in feature to easily produce user-customizable publication-grade clustermaps. Herein, we outline a complete reString protocol, showcasing its features on a real use-case.

Aims: The present investigation aimed at evaluating differences in psychiatric hospitalizations in Italy during and after the lockdown due to the novel coronavirus disease 2019 (COVID-19), compared to the same periods in 2018 and 2019. Methods: We obtained and analyzed anonymized data on psychiatric admissions (n = 4550) from 12 general hospital psychiatric wards (GHPWs) in different Italian regions (catchment area = 3.71 millions of inhabitants). Using a mixed-effects Poisson regression model, we compared admission characteristics across three periods: (a) March 1–June 30, 2018 and 2019; (b) March 1–April 30, 2020 (i.e., lockdown); and (c) May 1–June 30, 2020 (i.e., post-lockdown). Results: During the COVID-19 lockdown, there was a 41% reduction (IRR = 0.59; p < 0.001, CI: 0.45–0.79) in psychiatric admissions in the enrolled GHPWs with respect to the 2018 and 2019 control period. Conversely, admission rates in the post-lockdown period were similar to those observed in the control period. Notably, a consistent and significant reduction in psychiatric hospitalizations of older patients (aged >65 years) was observed in the lockdown (40%; IRR = 0.60; 95% CI: 0.44–0.82) and post-lockdown (28%; IRR = 0.72; 95% CI: 0.54–0.96) periods. Long-stay admissions (>14 days) increased (63%; IRR = 1.63; 95% CI: 1.32–2.02) during the lockdown and decreased by 39% thereafter (IRR = 0.61; 95% CI: 0.49–0.75). A significant 35% increase in patients reporting suicidal ideation was observed in the post-lockdown period, compared to the rate observed in the 2018 and 2019 control period (IRR = 1.35; 95% CI: 1.01–1.79). Conclusion: The COVID-19 lockdown was associated with changes in the number of psychiatric admissions, particularly for older patients and long-stay hospitalizations. Increased admission of patients reporting suicidal ideation in the post-lockdown period merits special attention. Further studies are required to gain insight into the observed phenomena.

Lipidomic analyses address the problem of characterizing the lipid components of given cells, tissues and organisms by means of chromatographic separations coupled to high-resolution, tandem mass spectrometry analyses. A number of software tools have been developed to help in the daunting task of mass spectrometry signal processing and cleaning, peak analysis and compound identification, and a typical finished lipidomic dataset contains hundreds to thousands of individual molecular lipid species. To provide researchers without a specific technical expertise in mass spectrometry the possibility of broadening the exploration of lipidomic datasets, we have developed liputils, a Python module that specializes in the extraction of fatty acid moieties from individual molecular lipids. There is no prerequisite data format, as liputils extracts residues from RefMet-compliant textual identifiers and from annotations of other commercially available services. We provide three examples of real-world data processing with liputils, as well as a detailed protocol on how to readily process an existing dataset that can be followed with basic informatics skills. ispartof: SCIENTIFIC REPORTS vol:10 issue:1 ispartof: location:England status: published

International audience; Scope Protein malnutrition is characterized by stunted growth, hepatic steatosis and a damaged gut mucosal architecture. Since high-fat shaped gut microbiota (HFM) has an increased ability in providing nutrients and energy from food to the host, the aim of this study is to determine whether such a microbiota could beneficially impact on the consequences of malnutrition. Methods and results The cecal content of specific pathogen free C57Bl/6J mice fed a high-fat diet or a low-protein diet is transplanted in two groups of germ-free C57Bl/6J recipient mice, which are subsequently fed a low-protein diet for 8 weeks. Body weight gain is comparable between the two groups of microbiota-recipient mice. The HFM led to a worsening of microvesicular steatosis and a decrease of plasma lipids compared to the low-protein shaped microbiota. In the small intestine of mice receiving the HFM, although significant histological differences are not observed, the expression of antimicrobial genes promoting oxidative stress and immune response at the ileal epithelium (Duox2, Duoxa2, Saa1, Ang4, Defa5) is increased. Conclusion The transplant of HFM in mice fed a low-protein diet represents a noxious stimulus for the ileal mucosa and impairs hepatic lipoprotein secretion, favoring the occurrence of hepatic microvesicular steatosis.

LPP3 is an integral membrane protein belonging to a family of enzymes (LPPs) that display broad substrate specificity and catalyse dephosphorylation of several lipid substrates, including lysophosphatidic acid and sphingosine-1-phosphate. In mammals, the LPP family consists of three enzymes named LPP1, LPP2 and LPP3, which are encoded by three independent genes, PLPP1, PLPP2 and PLPP3, respectively (formerly known as PPAP2A, PPAP2C, PPAP2B). These three enzymes, in vitro, do not seem to differ for catalytic activities and substrate preferences. However, in vivo targeted inactivation of the individual genes has indicated that the enzymes do not have overlapping functions and that LPP3, specifically, plays a crucial role in vascular development. In 2011, two genome-wide association studies have identified PLPP3 as a novel locus associated with coronary artery disease susceptibility. Shortly after these reports, tissue specific inactivation of PLPP3 in mice highlighted a specific role for LPP3 in vascular pathophysiology and, more recently, in atherosclerosis development. This review is aimed at providing an updated overview on the function of LPP3 in embryonic cardiovascular development and on the experimental and clinical evidences relating this enzyme to vascular cell functions and cardiovascular disease.

AimsIncreased Ankyrin Repeat Domain 1 (ANKRD1) levels linked to gain of function mutations have been associated to total anomalous pulmonary venous return and adult cardiomyopathy occurrence in humans. The link between increased ANKRD1 level and cardiac structural and functional disease is not understood. To get insight into this problem, we have generated a gain of function ANKRD1 mouse model by overexpressing ANKRD1 in the myocardium.Methods and resultsAnkrd1 is expressed non-homogeneously in the embryonic myocardium, with a dynamic nucleo-sarcomeric localization in developing cardiomyocytes. ANKRD1 transgenic mice present sinus venosus defect, which originates during development by impaired remodelling of early embryonic heart. Adult transgenic hearts develop diastolic dysfunction with preserved ejection fraction, which progressively evolves into heart failure, as shown histologically and haemodynamically. Transgenic cardiomyocyte structure, sarcomeric assembly, and stability are progressively impaired from embryonic to adult life. Postnatal transgenic myofibrils also present characteristic functional alterations: impaired compliance at neonatal stage and impaired lusitropism in adult hearts. Altogether, our combined analyses suggest that impaired embryonic remodelling and adult heart dysfunction in ANKRD1 transgenic mice present a common ground of initial cardiomyocyte defects, which are exacerbated postnatally. Molecular analysis showed transient activation of GATA4-Nkx2.5 transcription in early transgenic embryos and subsequent dynamic transcriptional modulation within titin gene.ConclusionsANKRD1 is a fine mediator of cardiomyocyte response to haemodynamic load in the developing and adult heart. Increased ANKRD1 levels are sufficient to initiate an altered cellular phenotype, which is progressively exacerbated into a pathological organ response by the high ventricular workload during postnatal life. Our study defines for the first time a unifying picture for ANKRD1 role in heart development and disease and provides the first mechanistic link between ANKRD1 overexpression and cardiac disease onset.

Epidemiologically, high-density lipoprotein (HDL) cholesterol levels have been inversely associated to cardiovascular (CV) events, although a Mendelian Randomisation Study had failed to establish a clear causal role. Numerous atheroprotective mechanisms have been attributed to HDL, the main being the ability to promote cholesterol efflux from arterial walls; anti-inflammatory effects related to HDL ligands such as S1P (sphingosine-1-phosphate), resolvins and others have been recently identified. Experimental studies and early clinical investigations have indicated the potential of HDL to slow progression or induce regression of atherosclerosis. More recently, the availability of different HDL formulations, with different phospholipid moieties, has allowed to test other indications for HDL therapy. Positive reports have come from studies on coronary stent biocompatibility, where the use of HDL from different sources reduced arterial cell proliferation and thrombogenicity. The observation that low HDL-C levels may be associated with an enhanced risk of heart failure (HF) has also suggested that HDL therapy may be applied to this condition. HDL infusions or apoA-I gene transfer were able to reverse heart abnormalities, reduce diastolic resistance and improve cardiac metabolism. HDL therapy may be effective not only in atherosclerosis, but also in other conditions, of relevant impact on human health. KEY MESSAGES: High-density lipoproteins have as a major activity that of removing excess cholesterol from tissues (particularly arteries). Knowledge on the activity of high-density lipoproteins on health have however significantly widened. HDL-therapy may help to improve stent biocompatibility and to reduce peripheral arterial resistance in heart failure.

Topiramate is an anticonvulsant drug also prescribed for migraine prophylaxis that acts through several mechanisms of action. Several studies indicate that topiramate induces weight loss and a moderate reduction of plasma lipids and glucose. Based on these favourable metabolic effects, aim of this study was to evaluate if topiramate could modulate atherosclerosis development and protect target organs of dysmetabolic conditions. Thirty apoE-deficient mice were divided into three groups and fed for 12 weeks a high fat diet (Control) or the same diet containing topiramate at 0.125% and 0.250%. Body weight, water and food intake were monitored throughout the study. Plasma lipids and glucose levels were measured and a glucose tolerance test was performed. Atherosclerosis development was evaluated in the whole aorta and at the aortic sinus. Histological analysis of liver, kidney and adipose tissue was performed. Topiramate did not affect weight gain and food intake. Glucose tolerance and plasma lipids were not changed and, in turn, atherosclerosis development was not different among groups. Topiramate did not modify liver and adipose tissue histology. Conversely, in the kidneys, the treatment reduced the occurrence of glomerular lipidosis by decreasing foam cells accumulation and reducing the expression of inflammatory markers. Blood urea nitrogen levels were also reduced by treatment. Our results indicate that topiramate does not affect atherosclerosis development, but preserves kidney structure and function. The study suggests that topiramate could be investigated in drug repurposing studies for the treatment of glomerular lipidosis.

Risk assessment tools, i.e., validated risk prediction algorithms, to estimate the patient’s 10-year risk of developing cardiovascular disease (CVD) should be used to identify high-risk people for primary prevention. Current evidence confirms that appropriate monitoring and control of risk factors either reduces the likelihood of CVD or slows down its progression. It is thus crucial that all health professionals make appropriate use of all the available intervention strategies to control risk factors: from dietary improvement and adequate physical activity to the use of functional foods, food supplements, and drugs. The gut microbiota, which encompasses 1 × 1014 resident microorganisms, has been recently recognized as a contributing factor in the development of human disease. This review examines the effect of both some vegetable food components belong to the “protein food group” and the underexploited protein-rich hempseed on cholesterolemia and gut microbiota composition.

Numerous randomized clinical trials have established statins as the major standard therapy for atherosclerotic diseases because these molecules decrease the plasma level of low-density lipoprotein (LDL) cholesterol and moderately increase that of plasma high-density lipoprotein (HDL) cholesterol. The reverse cholesterol transport pathway, mediated by HDL particles, has a relevant antiatherogenic potential. An important approach to HDL-targeted therapy is optimization of the HDL-cholesterol level and enhanced removal of plasma cholesterol, together with the prevention and mitigation of inflammation related to atherosclerosis. Small-molecule inhibitors of cholesteryl ester transfer protein (CETP) increase the HDL-cholesterol level in subjects with normal or low HDL-cholesterol. However, CETP inhibitors do not seem to reduce the risk of atherosclerotic diseases. HDL therapies using reconstituted HDL, including apolipoprotein (Apo) A-I Milano, ApoA-I mimetics, or full-length ApoA-I, are dramatically effective in animal models. Of those, the ApoA-I-mimetic peptide called FAMP effectively removes cholesterol via the ABCA1 transporter and acts as an antiatherosclerotic agent by enhancing the biological functions of HDL without elevating the HDL-cholesterol level. Our review of the literature leads us to conclude that HDL-targeted therapies have significant atheroprotective potential and thus may effectively treat patients with cardiovascular diseases.

The PLPP3 gene encodes for a ubiquitous enzyme that dephosphorylates several lipid substrates. Genome-wide association studies identified PLPP3 as a gene that plays a role in coronary artery disease susceptibility. The aim of the study was to investigate the effect of Plpp3 deletion on atherosclerosis development in mice. Because the constitutive deletion of Plpp3 in mice is lethal, conditional Plpp3 hepatocyte-specific null mice were generated by crossing floxed Plpp3 mice with animals expressing Cre recombinase under control of the albumin promoter. The mice were crossed onto the athero-prone apoE−/− background to obtain Plpp3f/fapoE−/−Alb-Cre+ and Plpp3f/fapoE−/−Alb-Cre− offspring, the latter of which were used as controls. The mice were fed chow or a Western diet for 32 or 12 weeks, respectively. On the Western diet, Alb-Cre+ mice developed more atherosclerosis than Alb-Cre− mice, both at the aortic sinus and aorta. Lipidomic analysis showed that hepatic Plpp3 deletion significantly modified the levels of several plasma lipids involved in atherosclerosis, including lactosylceramides, lysophosphatidic acids, and lysophosphatidylinositols. In conclusion, Plpp3 ablation in mice worsened atherosclerosis development. Lipidomic analysis suggested that the hepatic Plpp3 deletion may promote atherosclerosis by increasing plasma levels of several low-abundant pro-atherogenic lipids, thus providing a molecular basis for the observed results.

cope : Antarctic krill is a great source of n-3 fatty acids and high-quality proteins. Aim of the study was to evaluate the effect of Antarctic krill components on plasma lipids and atherosclerosis development. Methods and results : Sixty apoEKO mice were divided into four groups and fed Western diet (CONTROL) or Western-like diets, differing for protein or fat content. Specifically, casein or fat in CONTROL was partially replaced by krill proteins (PRO), krill oil (KRILL OIL), or both (KRILL OIL+PRO). In KRILL OIL+PRO and KRILL OIL, cholesterol levels were significantly lower than in CONTROL group. Atherosclerosis in aorta of PRO, KRILL OIL and KRILL OIL+PRO was lower than in CONTROL, whereas, at the aortic sinus, atherosclerosis reduction was only observed in KRILL OIL. Liver steatosis, commonly present in CONTROL and PRO animals, was sporadic in KRILL OIL+PRO and KRILL OIL mice. Krill oil containing diets affected the expression of genes involved in cholesterol metabolism, mainly HMG-CoA reductase. No reduced systemic inflammation was found in all groups. Conclusion : Krill oil containing diets were able to reduce cholesterol levels, inhibit plaque development and prevent liver damage. Krill proteins also reduced atherosclerosis development through mechanisms not involving lipid metabolism. This article is protected by copyright. All rights reserved

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BACKGROUND AND PURPOSE Besides a significant reduction of low-density lipoprotein (LDL) cholesterol, statins moderately increase high-density lipoprotein (HDL) levels. In vitro studies have indicated that this effect may be the result of an increased expression of apolipoprotein (apo)A-I, the main protein component of HDL. The aim of the present study was to investigate in vivo the effect of rosuvastatin on apoA-I expression and secretion in a transgenic mouse model for human apoA-I. EXPERIMENTAL APPROACH Human apoA-I transgenic mice were treated for 28 days with 5, 10 or 20 mg·kg−1·day−1 of rosuvastatin, the most effective statin in raising HDL levels. Possible changes of apoA-I expression by treatment were investigated by quantitative real-time RT-PCR on RNA extracted from mouse livers. The human apoA-I secretion rate was determined in primary hepatocytes isolated from transgenic mice from each group after treatment. KEY RESULTS Rosuvastatin treatment with 5 and 10 mg·kg−1·day−1 did not affect apoA-I plasma levels, whereas a significant decrease was observed in mice treated with 20 mg·kg−1·day−1 of rosuvastatin (−16%, P < 0.01). Neither relative hepatic mRNA concentrations of apoA-I nor apoA-I secretion rates from primary hepatocytes were influenced by rosuvastatin treatment at each tested dose. CONCLUSIONS AND IMPLICATIONS In human apoA-I transgenic mice, rosuvastatin treatment does not increase either apoA-I transcription and hepatic secretion, or apoA-I plasma levels. These results support the hypothesis that other mechanisms may account for the observed HDL increase induced by statin therapy in humans.

International audience; Hereditary systemic amyloidosis caused by apolipoprotein A-I variants is a dominantly inherited disease characterised by fibrillar deposits mainly localized in the kidneys, liver, testis and heart. We have previously shown that the apolipoprotein A-I variant circulates in plasma at lower levels than the wild-type form (Mangione P et al. 2001, Obici L et al. 2004) thus raising the possibility that the amyloid deposits could sequester the circulating amyloidogenic chain or that the intracellular quality control can catch and capture the misfolded amyloidogenic chain before the secretion. In this study we have measured plasma levels of the wild-type and the variant Leu75Pro apolipoprotein A-I in two young heterozygous carriers in which tissue amyloid deposition was still absent. In both cases, the mutant was present at significantly lower levels than the wild-type form, thus indicating that the low plasma concentration of the apolipoprotein A-I variant is not a consequence of the protein entrapment in the amyloid deposits. In order to explore the cell secretion of amyloidogenic apolipoprotein A-I variants, we have studied COS-7 cells expressing either wild-type apolipoprotein A-I or two amyloidogenic mutants: Leu75Pro and Leu174Ser. Quantification of intracellular and extracellular apolipoprotein A-I alongside the intra-cytoplasmatic localization indicates that, unlike the wild-type protein, both variants are retained within the cells and mainly accumulate in the endoplasmic reticulum. The low plasma concentration of amyloidogenic apolipoprotein A-I may therefore be ascribed to the activity of the intracellular quality control that represents a first line of defence against the secretion of pathogenic variants.

Controversial data on the lipid-lowering effect of dietary pea proteins have been provided and the mechanisms behind this effect are not completely understood. The aim of the study was to evaluate a possible hypolipidemic activity of a pea protein isolate and to determine whether pea proteins could affect the hepatic lipid metabolism through regulation of genes involved in cholesterol and fatty acid homeostasis. Rats were fed Nath's hypercholesterolemic diets for 28 days, the protein sources being casein or a pea protein isolate from Pisum sativum. After 14 and 28 days of dietary treatment, rats fed pea proteins had markedly lower plasma cholesterol and triglyceride levels than rats fed casein (p

High-density lipoprotein (HDL) therapy is an emerging area of therapeutic development in the cardiovascular field, aimed at supplementing and improving the vascular benefit exerted by current treatments. Several studies have clearly established that HDL-cholesterol (HDL-C) levels are a potent and independent epidemiologic risk factor for cardiovascular diseases; moreover, studies in animal models have established that HDL-C raising interventions, such as over-expression of apolipoprotein A-I (apoA-I), the major HDL protein component, reduce the extent of atherosclerosis. In vitro and in vivo experiments have provided mechanistic explanations for the atheroprotective effects of HDL. HDL not only mediates reverse cholesterol transport, but also exerts antioxidant, anti-inflammatory, antithrombotic and vasodilatory effects. These multiple antiatherosclerotic properties provide an excellent rationale for designing therapeutic interventions targeted at enhancing HDL/apoA-I levels, but also for considering a direct administration of HDL-apoA-I in a variety of cardiovascular diseases. We provide an overview and an update of all therapeutic applications of synthetic HDL tested in animal models or in clinical trials. HDL therapy has proven to be effective in promoting atherosclerosis regression not only in experimental models, but also in humans, whereas applications to other areas of cardiovascular disease have only, up to now, been tested in animal models.

The ANKRD1/CARP gene encodes a muscle-specific protein which has been implicated in transcriptional regulation and myofibrillar assembly. Several features at both the mRNA and protein levels define ANKRD1 as a gene whose expression is tightly regulated, and deregulated expression of this protein has been recently associated to human congenital heart disease. It is therefore crucial to define the intracellular pathways that regulate the ANKRD1 protein’s steady-state levels. Here, we show that ANKRD1 is a short-lived protein whose levels are tightly regulated by the 26S proteasome. In addition, a critical role for a putative PEST motif was established, although other degrons within the ANKRD1 protein are likely implicated in the control of its intracellular levels.

This review aims to provide an overview and an update of all therapeutic applications of synthetic high-density lipoproteins tested in animal models or in clinical trials.Starting from 1990, when plasma-derived high-density lipoproteins were administered for the first time to cholesterol-fed rabbits to evaluate a possible atherosclerosis regression, the efficacy of high-density lipoprotein therapy has been assessed in a variety of cardiovascular diseases. Synthetic high-density lipoproteins constituted by purified apolipoprotein (apo)A-I, recombinant apoA-I variants or small apoA-I-mimetic peptides complexed with phospholipids have proven their efficacy in animal models and recently also in humans. Clinical investigations on the effects of acute HDL treatment have been focused only on atherosclerosis regression. Short-term administration of the mutant apoA-IMilano provided clearcut benefit in coronary atheromas. More recently, treatment with synthetic high-density lipoproteins containing human purified apoA-I was associated with moderate activity in atheroma regression, albeit with some safety concerns at high doses.Administration of synthetic high-density lipoproteins has proven to be effective in promoting atherosclerosis regression not only in animal models, but also in humans. Applications to other areas of cardiovascular disease, such as restenosis and ischemia/reperfusion, have only, up to now, been tested in experimental models.

Objectives This study sought to evaluate in vivo the minimal dose of apolipoprotein (apo) A-IMilano phospholipid complex (recombinant apoA-IMilano and 1-palmitoyl-2-oleoyl phosphatidylcholine complexes [ETC-216]) able to induce atherosclerosis regression in a rabbit model of lipid-rich plaques. Background A single high dose of recombinant apoA-IMilano has promoted atherosclerosis regression in animal models. More recently, regression of atherosclerosis was achieved in coronary patients by repeated infusions of ETC-216. Methods Thirty-six rabbits underwent perivascular injury at both carotid arteries, followed by a 1.5% cholesterol diet. After 90 days, rabbits were randomly divided into 6 groups and treated 5 times with vehicle or ETC-216 at 5, 10, 20, 40, or 150 mg/kg dose every 4 days. Carotid plaque changes were evaluated in vivo by intravascular ultrasound (IVUS) and magnetic resonance imaging (MRI), performed before and at the end of treatments. Magnetic resonance imaging scans were also recorded after administration of the second dose for rabbits infused with vehicle 40 or 150 mg/kg. Results Atheroma volume in vehicle-treated rabbits increased dramatically between the first and the second IVUS analyses (+26.53%), whereas in ETC-216–treated animals, a reduced progression at the lower doses and a significant regression at the higher doses, up to −6.83%, was detected. Results obtained by MRI analysis correlated significantly with those at IVUS (r = 0.706; p Conclusions These results confirm the efficacy of ETC-216 for atherosclerosis treatment and provide guidance for dose selection and frequency to obtain a significant reduction of plaque volume.

Supplementary Material to this article is available at www.thrombosis-online.com.

Cutaneous lipids, endogenously synthetized and transported by lipoproteins, play a pivotal role in maintaining skin barrier. An impairment of extracutaneous lipid trafficking leads to the development of xanthomas, mostly arising in hyperlipidemic patients, but also in subjects with high-density lipoprotein (HDL) deficiency. The aim of this work was to evaluate, in a genetically modified mouse model, lacking two protein components of HDL particles, apolipoprotein(apo)E and apoA-I, the effect of HDL deficiency on skin morphology. Control mice (C57BL/6), apoE deficient mice (EKO), apoA-I deficient mice (A-IKO) and apoA-I/apoE double knockout mice (A-IKO/EKO) were maintained on a low-fat/low-cholesterol diet up to 30 weeks of age. At sacrifice, skin biopsies were processed for light (LM) and transmission electron microscopy (TEM). Whereas the skin of EKO, A-IKO, and C57BL/6 mice was comparable, LM analysis in A-IKO/EKO mice showed an increase in dermal thickness and the presence of foam cells and T lymphocytes in reticular dermis. TEM analysis revealed the accumulation of cholesterol clefts in the papillary dermis and of cholesterol crystals within foam cells. In conclusion, A-IKO/EKO mice represent an experimental model for investigating the cutaneous phenotype of human HDL deficiency, thus mimicking a condition in which human xanthomatous lesions can develop.

Background and purpose: Skeletal muscle injury by hypolipidemic drugs is not fully understood. An extensive analysis of the effect of chronic treatment with fluvastatin (5 mgkg-1 and 20 mgkg-1), atorvastatin (10 mgkg-1) and fenofibrate (60 mgkg-1) on rat skeletal muscle was undertaken.

In a study aimed at elucidation of the possible role of dietary phytoestrogens in the growth of breast cancer, it was necessary to develop a convenient, accurate, and reproducible method for the characterization and quantification of isoflavone metabolites in the serum of MMTV mice that were fed diets containing different amounts of these polyphenols. The analytical method is based on liquid chromatography with mass spectrometry in multiple reaction monitoring mode, using deuterated genistein as internal standard. The identified metabolites were genistein and dihydrodaidzein (DHD); their average concentrations in serum were 0.71 and 0.21 microM, respectively, for animals fed 1.5 mg/day of genistein and 0.7 mg/day of daidzein. This method assured a limit of quantification of 0.04 microM for genistein and 0.08 microM for DHD, and a limit of detection of 0.018 microM for genistein and 0.035 microM for DHD. The coefficient of variation was 8.9% for genistein and lower than 15% for DHD. This study provides the first data indicating the presence of dihydrodaidzein in serum of mice fed diets containing soy proteins.