scispace - formally typeset
Search or ask a question
Author

Francesca Zimetti

Bio: Francesca Zimetti is an academic researcher from University of Parma. The author has contributed to research in topics: Cholesterol & ABCA1. The author has an hindex of 21, co-authored 55 publications receiving 1462 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: It is concluded that apoA-I inhibits atherosclerosis by promoting both macrophage reverse cholesterol transport and HDL antiinflammatory function, and that these anti-atherogenic functions of apo-I are largely independent of the plasma level of HDL-C in this mouse model.
Abstract: To test the hypothesis that apolipoprotein A-I (apoA-I) functions specifically to inhibit atherosclerosis independent of the level of high-density lipoprotein cholesterol (HDL-C) by promoting both reverse cholesterol transport and HDL antiinflammatory function in vivo, we established a murine atherosclerosis model of apoA-I deficiency in which the level of HDL-C is well maintained. ApoA-I-/- mice were crossed with atherosclerosis susceptible low-density lipoprotein receptor-/-/apobec-/- (LA) mice to generate LA mice with apoA-I+/+, apoA-I+/-, and apoA-I-/- genotypes. There were no major differences in the amounts of non-HDL-C and HDL-C in the plasma between different apoA-I genotypes. A significant inverse relationship was observed, however, between apoA-I gene dose and atherosclerosis in both female and male mice. Compared with LA-apoA-I+/+ mice, serum from LA-apoA-I-/- mice had a significantly reduced capacity to function as an acceptor of ABCA1- and SR-BI-mediated cellular cholesterol efflux, and also had markedly reduced lecithin cholesterol acyltransferase activity. In addition, LA-apoA-I-/- mice had significantly reduced macrophage-derived cholesterol esterification and reverse cholesterol transport in vivo. There was significantly reduced plasma paraoxonase (PON-1) activity, impaired HDL vascular antiinflammatory function, and increased basal levels of monocyte chemotactic protein-1 in the plasma of LA-apoA-I-/- mice compared with LA-apoA-I+/+ mice. In LA-apoA-I-/- mice, there was also greater induction of some, but not all, inflammatory cytokines and chemokines in response to intraperitoneal injection of lipopolysaccharide than in LA-apoA-I+/+ mice. We conclude that apoA-I inhibits atherosclerosis by promoting both macrophage reverse cholesterol transport and HDL antiinflammatory function, and that these anti-atherogenic functions of apoA-I are largely independent of the plasma level of HDL-C in this mouse model.

175 citations

Journal ArticleDOI
TL;DR: Although some polyphenols might improve specific markers of cardiovascular risk and cognitive status, many inconsistent data are present in literature, therefore, definitive recommendations for the use of these compounds in the prevention of cardiovascular disease and cognitive decline are currently not applicable.
Abstract: Several studies have demonstrated that polyphenol-enriched diets may have beneficial effects against the development of degenerative diseases, including atherosclerosis and disorders affecting the central nervous system. This activity has been associated not only with antioxidant and anti-inflammatory properties, but also with additional mechanisms, such as the modulation of lipid metabolism and gut microbiota function. However, long-term studies on humans provided controversial results, making the prediction of polyphenol impact on health uncertain. The aim of this review is to provide an overview and critical analysis of the literature related to the effects of the principal dietary polyphenols on cardiovascular and neurodegenerative disorders. We critically considered and meta-analyzed randomized controlled clinical trials involving subjects taking polyphenol-based supplements. Although some polyphenols might improve specific markers of cardiovascular risk and cognitive status, many inconsistent data are present in literature. Therefore, definitive recommendations for the use of these compounds in the prevention of cardiovascular disease and cognitive decline are currently not applicable. Once pivotal aspects for the definition of polyphenol bioactivity, such as the characterization of pharmacokinetics and safety, are addressed, it will be possible to have a clear picture of the realistic potential of polyphenols for disease prevention.

155 citations

Journal ArticleDOI
TL;DR: In this paper, the capacity of high-density lipoproteins (HDL) to promote cell cholesterol efflux is investigated in rheumatoid arthritis (RA) and systemic lupus erythemathosus (SLE) patients.
Abstract: Objectives The marked cardiovascular risk in autoimmune diseases is only partly explained. The capacity of high-density lipoproteins (HDL) to promote cell cholesterol efflux is a property with a well-known anti-atherogenic significance, but is also involved in functional modulation of endothelial and immune cells. The aim of this work was to evaluate HDL functionality with respect to cell cholesterol efflux in rheumatoid arthritis (RA) and systemic lupus erythemathosus (SLE) patients. Methods We evaluated serum cholesterol efflux capacity (CEC) of apoB-depleted serum, which mainly reflects HDL activity, from 30 RA and 30 SLE patients, and from 30 healthy controls by radioisotopic ex-vivo systems discriminating between the specific pathways of cholesterol efflux. Results RA patients presented impairment of ATP-binding cassette G1-mediated CEC that correlated with disease activity. SLE patients showed a more complex pattern of modifications unrelated to disease activity, with marked reduction of ATP-binding cassette G1-mediated CEC and impairment of ATP-binding cassette A1-mediated CEC. The relationship between specific pathways of CEC values and serum total HDL differed between groups and there was no relationship with autoantibody profile or current therapy. Conclusions CEC is impaired in RA and SLE, with a specific mechanism pattern in each disease not depending on serum HDL levels. These findings provide a new mechanism for the increased atherosclerotic risk in RA and SLE patients.

138 citations

Journal ArticleDOI
TL;DR: Probucol is an effective inhibitor of ABCA1-mediated cholesterol efflux without influencing scavenger receptor class B type I–mediated efflux, which may in part explain the reported in vivo high-density lipoprotein–lowering action of probucol.
Abstract: Objective— ATP-binding cassette transporter A1 (ABCA1) mediates the efflux of lipids from cells to lipid-poor apolipoproteins. In this article, we characterize the effect of probucol on cellular ABCA1-mediated lipid efflux. Methods and Results— Probucol inhibited cholesterol efflux up to 80% in J774 macrophages expressing ABCA1. In Fu5AH hepatoma cells that contain scavenger receptor class B, type I, but not functional ABCA1, we observed no effect of probucol on cholesterol efflux. Probucol inhibited cholesterol efflux from normal human skin fibroblasts but not from fibroblasts from a Tangier patient. Fluorescent confocal microscopy and biotinylation assay demonstrated that in J774 cells probucol impaired the translocation of ABCA1 from intracellular compartments to the plasma membrane. Probucol also inhibited the formation of an ABCA1-linked cholesterol oxidase sensitive plasma membrane domain. Consistent with the inhibitory effect on ABCA1 translocation to the plasma membrane, probucol reduced cell surface–specific [ 125 I]-labeled apolipoprotein-AI binding. Conclusions— We conclude that probucol is an effective inhibitor of ABCA1-mediated cholesterol efflux without influencing scavenger receptor class B type I–mediated efflux. The inhibition of ABCA1 translocation to the plasma membrane may in part explain the reported in vivo high-density lipoprotein–lowering action of probucol.

137 citations

Journal ArticleDOI
TL;DR: The results indicate that chymase treatment of HDL3 specifically impairs the ABCA1-dependent pathway without influencing either aqueous or SR-BI-facilitated diffusion and that this effect is caused by depletion of lipid-poor pre-β-migrating particles in HDL3.

124 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: Therapeutic interventions such as increased production or infusion of high-density lipoproteins may sever the links between cholesterol accumulation and inflammation, and have beneficial effects in patients with metabolic diseases.
Abstract: Hypercholesterolaemia leads to cholesterol accumulation in macrophages and other immune cells, which promotes inflammatory responses, including augmentation of Toll-like receptor (TLR) signalling, inflammasome activation, and the production of monocytes and neutrophils in the bone marrow and spleen. On a cellular level, activation of TLR signalling leads to decreased cholesterol efflux, which results in further cholesterol accumulation and the amplification of inflammatory responses. Although cholesterol accumulation through the promotion of inflammatory responses probably has beneficial effects in the response to infections, it worsens diseases that are associated with chronic metabolic inflammation, including atherosclerosis and obesity. Therapeutic interventions such as increased production or infusion of high-density lipoproteins may sever the links between cholesterol accumulation and inflammation, and have beneficial effects in patients with metabolic diseases.

972 citations

Journal ArticleDOI
TL;DR: The present update extends on the evidence that CVD risk in the whole spectrum of IJD is increased, which underscores the need for CVDrisk management in these patients.
Abstract: Patients with rheumatoid arthritis (RA) and other inflammatory joint disorders (IJD) have increased cardiovascular disease (CVD) risk compared with the general population. In 2009, the European League Against Rheumatism (EULAR) taskforce recommended screening, identification of CVD risk factors and CVD risk management largely based on expert opinion. In view of substantial new evidence, an update was conducted with the aim of producing CVD risk management recommendations for patients with IJD that now incorporates an increasing evidence base. A multidisciplinary steering committee (representing 13 European countries) comprised 26 members including patient representatives, rheumatologists, cardiologists, internists, epidemiologists, a health professional and fellows. Systematic literature searches were performed and evidence was categorised according to standard guidelines. The evidence was discussed and summarised by the experts in the course of a consensus finding and voting process. Three overarching principles were defined. First, there is a higher risk for CVD in patients with RA, and this may also apply to ankylosing spondylitis and psoriatic arthritis. Second, the rheumatologist is responsible for CVD risk management in patients with IJD. Third, the use of non-steroidal anti-inflammatory drugs and corticosteroids should be in accordance with treatment-specific recommendations from EULAR and Assessment of Spondyloarthritis International Society. Ten recommendations were defined, of which one is new and six were changed compared with the 2009 recommendations. Each designated an appropriate evidence support level. The present update extends on the evidence that CVD risk in the whole spectrum of IJD is increased. This underscores the need for CVD risk management in these patients. These recommendations are defined to provide assistance in CVD risk management in IJD, based on expert opinion and scientific evidence.

865 citations

Journal ArticleDOI
TL;DR: High-density lipoprotein has been proposed to have several antiatherosclerotic properties, including the ability to mediate macrophage cholesterol efflux, antioxidant capacity, antiinflammatory properties, nitric oxide–promoting activity, and ability to transport proteins with their own intrinsic biological activities.
Abstract: High-density lipoprotein (HDL) has been proposed to have several antiatherosclerotic properties, including the ability to mediate macrophage cholesterol efflux, antioxidant capacity, antiinflammatory properties, nitric oxide–promoting activity, and ability to transport proteins with their own intrinsic biological activities.1 HDL particles are critical acceptors of cholesterol from lipid-laden macrophages and thereby participate in the maintenance of net cholesterol balance in the arterial wall and in the reduction of proinflammatory responses by arterial cholesterol-loaded macrophages. The pathways that regulate HDL-mediated macrophage cholesterol efflux and disposition of cholesterol involve cell membrane–bound transporters, plasma lipid acceptors, plasma proteins and enzymes, and hepatic cellular receptors (Figure 1). From the earliest proposed concept for HDL-mediated cholesterol efflux,2,3 the concentration of the cholesterol content in HDL particles has been considered a surrogate measurement for the efficiency of the “reverse cholesterol transport” (RCT) process; however, macrophage-derived cholesterol represents a minor component of the cholesterol transported by HDL particles.4–7 One important pathway for cholesterol-mediated efflux from macrophage foam cells involves interaction between the ATP-binding cassette transporter A1 (ABCA1) and cholesterol-deficient and phospholipid-depleted apolipoprotein (apo) A-I complexes (pre-β migrating HDL or very small HDL [HDL-VS]; Figure 2).1,8 Subsequently, the ATP-binding cassette transporter G1 (ABCG1) mediates macrophage cholesterol efflux through interactions (Figure 3) with spherical, cholesterol-containing α-HDL particles (small HDL [HDL-S], medium HDL [HDL-M], large HDL [HDL-L], and very large (HDL-VL).1 In contrast, the scavenger receptor class B type I (SR-BI) is a multifunctional receptor that mediates bidirectional lipid transport in the macrophage, which is dependent on the content of cholesterol in lipid-laden macrophages. A more established role for SR-BI in cholesterol trafficking involves selective uptake of cholesteryl esters from mature HDL by the liver. Recent studies suggest that polymorphisms in SR-BI contribute to the functional capacity of this cholesterol …

778 citations