Publications by authors named "Mariarosaria Napolitano"

35 Publications

[The biological resources and molecule archives organization: turn a need into an opportunity for the Smart Specialization Strategy of the Lazio region.]

Recenti Prog Med 2019 Feb;110(2):68-74

Istituto Superiore di Sanità, Roma.

Smart Specialization Strategy (S3) of Lazio defines smart specialization strategies to bring out the excellence of the territory with prospects of success on the global market. Chemical-pharmaceutical, biomedical and biotechnological field is one of the 7 sectors considered of greatest interest for the S3. Key engine of biotechnology development are biological materials and associated data, stored in biobanks. However, to ensure that the research and product development carried out with that resources gives statistically significant and reproducible results, it is essential that they are collected, manipulated and stored using standardized and traced methods. Implementation of the recent published standard ISO 20387- "Biotechnology-Biobanking-General requirements for biobanking" is bridging biobanks toward to storage and distribution of qualified biological material only. Human biobanks are also an essential part of the assistance and care of the citizen and constitute an unavoidable cost of the regional health system. However, biobanks organization, rationalization of their territorial distribution, completion of the process of recognition and regional accreditation, parallel to the implementation of the offer of remunerated services for biobanking, can turn the cost of the necessary preservation of the samples, into an opportunity of territorial development. The paper describes the necessity, shared by a working group represented by several Lazio biobanks, of including biobank activities in the virtuous circle designed by the S3,concretizing the framework prefigured by the S3 document on infrastructures for research, innovation and technology transfer. To allow inclusion of biobank activities in the virtuous circle, we underline the need to quickly start the process of recognition of the territorial research biobanks, to implement at regional level the process of optimization and rationalization of the management of biological samples, in accordance with the international harmonization standards and with the territorial indications of sustainability.
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http://dx.doi.org/10.1701/3112.31001DOI Listing
February 2019

Improvable Lifestyle Factors in Lymphoma Survivors.

Acta Haematol 2018;139(4):235-237. Epub 2018 Jun 21.

Haematology Unit, IRCCS Istituto Tumori "Giovanni Paolo II", Bari, Italy.

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http://dx.doi.org/10.1159/000489252DOI Listing
March 2019

Improving Provision of Care for Long-term Survivors of Lymphoma.

Clin Lymphoma Myeloma Leuk 2017 Dec 17;17(12):e1-e9. Epub 2017 Aug 17.

Hematology and Cell Therapy Unit, IRCCS-Istituto Tumori "Giovanni Paolo II", Bari, Italy.

The progressive improvement of lymphoma therapies has led to a significant prolongation of patient survival and life expectancy. However, lymphoma survivors are at high risk of experiencing a range of early and late adverse effects associated with the extent of treatment exposure. Among these, second malignancies and cardiopulmonary diseases can be fatal, and neurocognitive dysfunction, endocrinopathy, muscle atrophy, and persistent fatigue can affect patients' quality of life for decades after treatment. Early recognition and reduction of risk factors and proper monitoring and treatment of these complications require well-defined follow-up criteria, close coordination among specialists of different disciplines, and a tailored model of survivorship care. We have summarized the major aspects of therapy-related effects in lymphoma patients, reviewed the current recommendations for follow-up protocols, and described a new hospital-based model of survivorship care provision from a recent multicenter Italian experience.
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http://dx.doi.org/10.1016/j.clml.2017.08.097DOI Listing
December 2017

Business Planning in Biobanking: How to Implement a Tool for Sustainability.

Biopreserv Biobank 2017 Feb 29;15(1):46-56. Epub 2016 Nov 29.

2 Departments of Haematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità , Rome, Italy .

Worldwide, the sustainability of public health systems is challenged by the increasing number and cost of personalized therapies. Quality biological samples stored in biobanks are essential for the provision of appropriate health services and also act as a reservoir for the development of precision medicine and biotechnological innovation. Economic sustainability is a crucial factor in the maintenance of biobanking activities. Traditionally, management of biobanking is performed by health researchers and/or clinicians whose knowledge of economic issues is inadequate. On the other hand, familiarity with financial instruments used by economists is not often accompanied by a consolidated understanding of biobanking features. This article aims to be a guide for the implementation of business plans in biobanking and proposes models for the facilitation of their preparation, thus contributing to recognition of the importance of efficient management of resources of public health services.
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http://dx.doi.org/10.1089/bio.2016.0045DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5327055PMC
February 2017

The Emerging Role of Disturbed CoQ Metabolism in Nonalcoholic Fatty Liver Disease Development and Progression.

Nutrients 2015 Dec 1;7(12):9834-46. Epub 2015 Dec 1.

Department of Haematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome 00161, Italy.

Although non-alcoholic fatty liver disease (NAFLD), characterised by the accumulation of triacylglycerol in the liver, is the most common liver disorder, the causes of its development and progression to the more serious non-alcoholic steatohepatitis (NASH) remain incompletely understood. Oxidative stress has been implicated as a key factor in both these processes, and mitochondrial dysfunction and inflammation are also believed to play a part. Coenzyme Q (CoQ) is a powerful antioxidant found in all cell membranes which has an essential role in mitochondrial respiration and also has anti-inflammatory properties. NAFLD has been shown to be associated with disturbances in plasma and liver CoQ concentrations, but the relationship between these changes and disease development and progression is not yet clear. Dietary supplementation with CoQ has been found to be hepatoprotective and to reduce oxidative stress and inflammation as well as improving mitochondrial dysfunction, suggesting that it may be beneficial in NAFLD. However, studies using animal models or patients with NAFLD have given inconclusive results. Overall, evidence is now emerging to indicate that disturbances in CoQ metabolism are involved in NAFLD development and progression to NASH, and this highlights the need for further studies with human subjects to fully clarify its role.
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http://dx.doi.org/10.3390/nu7125501DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4690053PMC
December 2015

Intratumoral injection of IFN-alpha dendritic cells after dacarbazine activates anti-tumor immunity: results from a phase I trial in advanced melanoma.

J Transl Med 2015 May 2;13:139. Epub 2015 May 2.

Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, viale Regina Elena 299, Rome, 00161, Italy.

Background: Advanced melanoma patients have an extremely poor long term prognosis and are in strong need of new therapies. The recently developed targeted therapies have resulted in a marked antitumor effect, but most responses are partial and some degree of toxicity remain the major concerns. Dendritic cells play a key role in the activation of the immune system and have been typically used as ex vivo antigen-loaded cell drugs for cancer immunotherapy. Another approach consists in intratumoral injection of unloaded DCs that can exploit the uptake of a wider array of tumor-specific and individual unique antigens. However, intratumoral immunization requires DCs endowed at the same time with properties typically belonging to both immature and mature DCs (i.e. antigen uptake and T cell priming). DCs generated in presence of interferon-alpha (IFN-DCs), due to their features of partially mature DCs, capable of efficiently up-taking, processing and cross-presenting antigens to T cells, could successfully carry out this task. Combining intratumoral immunization with tumor-destructing therapies can induce antigen release in situ, facilitating the injected DCs in triggering an antitumor immune response.

Methods: We tested in a phase I clinical study in advanced melanoma a chemo-immunotherapy approach based on unloaded IFN-DCs injected intratumorally one day after administration of dacarbazine. Primary endpoint of the study was treatment safety and tolerability. Secondary endpoints were immune and clinical responses of patients.

Results: Six patients were enrolled, and only three completed the treatment. The chemo-immunotherapy was well tolerated with no major side effects. Three patients showed temporary disease stabilization and two of them showed induction of T cells specific for tyrosinase, NY-ESO-1 and gp100. Of interest, one patient showing a remarkable long-term disease stabilization kept showing presence of tyrosinase specific T cells in PBMC and high infiltration of memory T cells in the tumor lesion at 21 months.

Conclusion: We tested a chemo-immunotherapeutic approach based on IFN-DCs injected intratumorally one day after DTIC in advanced melanoma. The treatment was well tolerated, and clinical and immunological responses, including development of vitiligo, were observed, therefore warranting additional clinical studies aimed at evaluating efficacy of this approach.

Trial Registration: Trial Registration Number not publicly available due to EudraCT regulations: https://www.clinicaltrialsregister.eu/doc/EU_CTR_FAQ.pdf.
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http://dx.doi.org/10.1186/s12967-015-0473-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4438625PMC
May 2015

Development of a pilot project on data sharing among partners of the Italian Hub of Population Biobanks (HIBP): association between lipid profile and socio-demographic variables.

Biopreserv Biobank 2014 Aug 30;12(4):225-33. Epub 2014 Jul 30.

1 Department of Haematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità , Rome, Italy .

The Italian Hub of Population Biobanks (HIBP) includes both ongoing and completed studies that are heterogeneous in both their purpose and in the specimens collected. The heterogeneity in starting conditions makes sharing study data very difficult because of technical, ethical, and collection rights issues that hamper collaboration and synergy. With the aim of overcoming these difficulties and establishing the "proof-of-concept" that sharing studies is achievable among Italian collections, a data-sharing pilot project has been agreed to by HIBP members. Participants agreed to the general methodology and signed a shared Data Transfer Agreement. The biobanks involved were: EURAC (Micros study), CIG (GEHA project), CNESPS (FINE, MATISS, MONICA, OEC1998, ITR (Italian Twin Register), and IPREA studies, and MOLIBANK (Moli-Sani project). Biobank data were uploaded into a common database using a dedicated informatics infrastructure. Demographic data, and anthropometric and hematochemical parameters were shared for each record. Each biobank uploaded into the common database a dataset with a minimum of 1000 subjects, for a total of 5071 records. After a harmonization process, the final dataset included 3882 records. Subjects were grouped into three main geographic areas of Italy (North, Center, and South) and separate analyses were performed for men and women. The 3882 records were analyzed through multivariate logistic regression analysis. Results were expressed as odds ratios with 95% confidence interval. Results show several geographical differences in the lipidemic pattern, mostly regarding cholesterol-HDL, which represents a strong basis for further, deeper sample-based studies. This HIBP pilot study aimed to prove the feasibility of such collaborations and it provides a methodological prototype for future studies based on the participation in the partnership of well-established quality collections.
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http://dx.doi.org/10.1089/bio.2014.0001DOI Listing
August 2014

The European Research Infrastructures of the ESFRI Roadmap in Biological and Medical Sciences: status and perspectives.

Ann Ist Super Sanita 2014 ;50(2):178-85

Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, Italy.

Introduction: Since 2002, the European Strategy Forum on Research Infrastructures identified the needs for Research Infrastructures (RIs) in Europe in priority fields of scientific research and drafted a strategic document, the ESFRI Roadmap, defining the specific RIs essential to foster European research and economy. The Biological and Medical Sciences RIs (BMS RIs) were developed thanks to the active participation of many institutions in different European member states associated to address the emerging needs in biomedicine and, among these, the Italian National Institute of Health (ISS), in virtue of its role in public health and research, has been specifically involved in the national development and implementation of three RIs: the Biobanking and Biomolecular Resources Research Infrastructure (BBMRI), the European Advanced Translational Research Infrastructure in Medicine (EATRIS) and the European Clinical Research Infrastructures Network (ECRIN).

Aim: This article outlines the design and development of these RIs up to the recent achievement of the ERIC status, their importance in the Horizon 2020 programme and their societal and economic potential impact, with special attention to their development and significance in Italy.

Conclusions: The ISS plays a unique role in fostering a coordinated participation of excellence Italian institutes/facilities to different European biomedical RIs, thus contributing to health innovation, healthcare optimization, and healthcare cost containment.
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http://dx.doi.org/10.4415/ANN_14_02_12DOI Listing
September 2015

The Italian Hub of Population Biobanks as a potential tool for improving public health stewardship.

Biopreserv Biobank 2013 Jun;11(3):173-5

In Italy, a country that is experiencing the decentralization of health services from central to regional level of government, the Minister of Health is proposing stewardship as a model of governance for the public health system. Stewardship favors efficiency in the policy decision-making process, based on reciprocal trust, and tends to be more ethical. The embryonic proposal to test stewardship in the field of population-based research was advanced during the launching conference Challenges and Opportunities of the Italian Hub of Population Biobanks (HIBP) held in 2012 in Rome. Resources collected by population biobanks (i.e., blood and its derivatives, and/or DNA isolated from any type of biological samples and relative associated data) have, in fact, a recognized scientific value for the investigation of links between genetics, health and life style, and epidemiological outcomes through population biobank-based studies, and are essential to planning effective and qualified interventions for public health. The current economic crisis requires a strong push to rationalize investment in health policies. In particular, population biobank-based studies require financial commitment, often of long duration, for the realization of their goals. Thus, innovative solutions to allow fast integration of scientific knowledge into political health strategy are required. During the conference in Rome, it was proposed to test the stewardship model by its application to the inter-relationship between population biobank-based studies and disease prevention. Stewardship minimizes barriers to innovation and uses information more effectively to better develop new strategies for prevention and/or treatment. In the months following the conference, the proposal was defined more clearly, and the HIBP network became a potential tool for testing and implementing this model in the Italian Public Health prevention system.
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http://dx.doi.org/10.1089/bio.2012.0064DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3696929PMC
June 2013

Review of the Italian current legislation on research biobanking activities on the eve of the participation of national biobanks’ network in the legal consortium BBMRI-ERIC.

Biopreserv Biobank 2013 Apr;11(2):124-8

The ethical-legal framework of research biobanking activities is still scarcely defined in Italy, and this constitutes a major obstacle to exploit the potential benefits of existing bioresource patrimony at the national and international levels. Biobanking and Biomolecular Resources Research Infrastructure (BBMRI), which aims to become a major interface between biological samples and data and top-level biological and medical research, is undertaking the crucial transformation to the ERIC (European Research Infrastructure Consortium) legal entity. In this scenario, there is a need to address the national legal and ethical concerns that are strictly correlated with the use of human biosources in research across European countries participating (and not) in BBMRI. In this perspective, this article aims to review the legal framework applying to research biobanking in Italy, including both "soft" nonbinding instruments and binding regulations. Since ethical and societal aspects impact biobanking research activities, the article discusses both the critical ethical and legal open issues that need to be implemented at the national level.
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http://dx.doi.org/10.1089/bio.2012.0058DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3696949PMC
April 2013

Postprandial human triglyceride-rich lipoproteins increase chemoattractant protein secretion in human macrophages.

Cytokine 2013 Jul 15;63(1):18-26. Epub 2013 May 15.

Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore di Sanitá, Viale Regina Elena, 299, 00161 Rome, Italy. Electronic address:

This study tested the hypothesis that postprandial triglyceride-rich lipoproteins (ppTGRL) have inflammatory effects in primary human monocyte-derived macrophages (HMDM). ppTGRL were isolated from normolipidemic human volunteers, and the production of chemokines and of inflammatory prostaglandins and leukotrienes via the arachidonic acid cascade in HMDM was determined, and their effect on monocyte chemotaxis were assessed. In addition, the possible role of extracellular lipases in the inflammatory effects of ppTGRL was evaluated. ppTGRL were found to increase the secretion of chemoattractants, including monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein (MIP)-1α and -1β and IL-8, by HMDM and to have a stimulatory effect on monocyte chemotaxis. HMDM secretion of leukotrienes B4 (LTB4) and lipoxin A (LXA4), which are potent activators of monocyte migration, was also stimulated by ppTGRL. Inclusion of the lipoprotein lipase (LPL) inhibitor orlistat did not alter the effects of ppTGRL on chemokine production, and the expression of mRNA for LPL and other secreted lipases was unaffected by the lipoproteins. These findings support the hypothesis that ppTGRL induce the secretion of chemokines by macrophages which promote monocyte recruitment, and that extracellular lipolysis of the particles is not required for these effects and provide further evidence to indicate that the postprandial lipoproteins contribute to a pro-atherogenic pattern after a fat-rich meal.
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http://dx.doi.org/10.1016/j.cyto.2013.04.025DOI Listing
July 2013

Role of macrophage activation in the lipid metabolism of postprandial triacylglycerol-rich lipoproteins.

Exp Biol Med (Maywood) 2013 Jan;238(1):98-110

Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.

The potential link between the inflammatory effects of postprandial lipemia and the induction of macrophage foam cell formation by triacylglycerol-rich lipoproteins (TGRL) was studied using postprandial triacylglycerol-rich lipoproteins (ppTGRL) derived from human volunteers and primary human monocyte-derived macrophages (HMDM). Subjects were fed a test meal high in dairy fat, followed three hours later by isolation of serum ppTGRL. Pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes were induced in HMDM by treatment with lipopolysaccharide (LPS) or dexamethasone (DEX), respectively. ppTGRL caused a dose-dependent increase in both triacylglycerol (TG) and cholesterol (CH) accumulation in the cells. TG accumulation was unaffected by LPS or DEX treatment, but LPS as compared with DEX-treated HMDM were found to accumulate more CH, and this effect was greater than that induced by ppTGRL in untreated cells. LPS-treatment had no effect on lipid uptake from ppTGRL (via the LDLr, scavenger receptors or SR-B1) or on CH efflux, but the CH synthesis inhibitor mevinolin abolished the difference between CH accumulation in LPS-and DEX-treated cells, suggesting that CH synthesis is enhanced in the inflammatory state. Phospholipid (PL) synthesis was increased in inflammatory M1 as compared with anti-inflammatory M2 HMDM. Moreover, TG synthesis was decreased by ppTGRL in DEX-treated as compared with untreated cells. We conclude, therefore, inflammation causes a greater increase in the accumulation of neutral lipids than ppTGRL in macrophages, and that this effect is related to modulation of PL metabolism and possibly also CH synthesis. Thus, the inflammatory phenotype of macrophages influences their lipid metabolism, and is, therefore, likely to modulate the induction of macrophage lipid accumulation by lipoproteins associated with foam cell formation.
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http://dx.doi.org/10.1258/ebm.2012.012091DOI Listing
January 2013

Coenzyme Q metabolism is disturbed in high fat diet-induced non-alcoholic fatty liver disease in rats.

Int J Mol Sci 2012 2;13(2):1644-57. Epub 2012 Feb 2.

Department of Cell Biology and Neuroscience, National Institute of Health, Rome 00161, Italy; E-Mail:

Oxidative stress is believed to be a major contributory factor in the development of non alcoholic fatty liver disease (NAFLD), the most common liver disorder worldwide. In this study, the effects of high fat diet-induced NAFLD on Coenzyme Q (CoQ) metabolism and plasma oxidative stress markers in rats were investigated. Rats were fed a standard low fat diet (control) or a high fat diet (57% metabolizable energy as fat) for 18 weeks. The concentrations of total (reduced + oxidized) CoQ9 were increased by >2 fold in the plasma of animals fed the high fat diet, while those of total CoQ10 were unchanged. Reduced CoQ levels were raised, but oxidized CoQ levels were not, thus the proportion in the reduced form was increased by about 75%. A higher percentage of plasma CoQ9 as compared to CoQ10 was in the reduced form in both control and high fat fed rats. Plasma protein thiol (SH) levels were decreased in the high fat-fed rats as compared to the control group, but concentrations of lipid hydroperoxides and low density lipoprotein (LDL) conjugated dienes were unchanged. These results indicate that high fat diet-induced NAFLD in rats is associated with altered CoQ metabolism and increased protein, but not lipid, oxidative stress.
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http://dx.doi.org/10.3390/ijms13021644DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3291983PMC
July 2015

Phospholipase A2 mediates apolipoprotein-independent uptake of chylomicron remnant-like particles by human macrophages.

Int J Vasc Med 2012 21;2012:501954. Epub 2011 Aug 21.

Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.

Apolipoprotein E-receptor-mediated pathways are the main routes by which macrophages take up chylomicron remnants, but uptake may also be mediated by receptor-independent routes. To investigate these mechanisms, triacylglycerol (TG) accumulation induced by apolipoprotein-free chylomicron remnant-like particles (CRLPw/o) in human monocyte-derived macrophages was evaluated. Macrophage TG content increased about 5-fold after incubation with CRLPw/o, and this effect was not reduced by the inhibition of phagocytosis, macropinocytosis, apolipoprotein E function, or proteoglycan bridging. The role of lipases, including lipoprotein lipase, cholesteryl ester hydrolase, and secretory (sPLA2) and cytosolic phospholipase A2, was studied using [(3)H]TG-labelled CRLPw/o. Total cell radioactivity after incubation with [(3)H]TG CRLPw/o was reduced by 15-30% by inhibitors of lipoprotein lipase and cholesteryl ester hydrolase and by about 45% by inhibitors of sPLA2 and cytosolic PLA(2) . These results suggest that macrophage lipolytic enzymes mediate the internalization of postprandial TG-rich lipoproteins and that sPLA(2) and cytosolic PLA2, play a more important role than extracellular lipoprotein lipase-mediated TG hydrolysis.
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http://dx.doi.org/10.1155/2012/501954DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3160105PMC
November 2011

High fat diet-induced non alcoholic fatty liver disease in rats is associated with hyperhomocysteinemia caused by down regulation of the transsulphuration pathway.

Lipids Health Dis 2011 Apr 19;10:60. Epub 2011 Apr 19.

Department of Cellular Biology and Neuroscience, Istituto Superiore Sanità, Rome, Italy.

Background: Hyperhomocysteinemia (HHcy) causes increased oxidative stress and is an independent risk factor for cardiovascular disease. Oxidative stress is now believed to be a major contributory factor in the development of non alcoholic fatty liver disease, the most common liver disorder worldwide. In this study, the changes which occur in homocysteine (Hcy) metabolism in high fat-diet induced non alcoholic fatty liver disease (NAFLD) in rats were investigated.

Methods And Results: After feeding rats a standard low fat diet (control) or a high fat diet (57% metabolisable energy as fat) for 18 weeks, the concentration of homocysteine in the plasma was significantly raised while that of cysteine was lowered in the high fat as compared to the control diet fed animals. The hepatic activities of cystathionine β-synthase (CBS) and cystathionine γ-lyase (CGS), the enzymes responsible for the breakdown of homocysteine to cysteine via the transsulphuration pathway in the liver, were also significantly reduced in the high fat-fed group.

Conclusions: These results indicate that high fat diet-induced NAFLD in rats is associated with increased plasma Hcy levels caused by down-regulation of hepatic CBS and CGL activity. Thus, HHcy occurs at an early stage in high fat diet-induced NAFLD and is likely to contribute to the increased risk of cardiovascular disease associated with the condition.
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http://dx.doi.org/10.1186/1476-511X-10-60DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3096990PMC
April 2011

Neutrophil unsaturated fatty acid release by GM-CSF is impaired in cystic fibrosis.

Lipids Health Dis 2010 Nov 8;9:129. Epub 2010 Nov 8.

Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Viale Regina Elena, 199-00161 Roma, Italy.

Dysregulated inflammation in cystic fibrosis (CF) is attributed to an altered production of inflammatory mediators derived from polyunsaturated lipids. In comparison to the arachidonic acid (AA) cascade, little is known about the modulation of docosahexaenoic acid (DHA) membrane release. We compared data on neutrophil DHA- and AA- release from both control (CT) and patients with CF using [3H]AA or [14C]DHA as a markers for, respectively, AA and DHA- release. Granulocyte-macrophage-colony stimulating factor stimulated DHA release from CT, but not CF, neutrophils. Comparison showed that both [14C]DHA and [3H]AA liberated after stimulation was higher in CT than in CF neutrophils. Since bioactive mediators derived from DHA are resolving factors and those derived from AA are both pro- and anti- inflammatory, these results suggest that CF is associated with a reduction of the release of PUFA-precursors of lipooxygenated resolving mediators. This leads to the hypothesis that defects in the resolving factors production could contribute to the inflammatory dysregulated processes in CF. Furthermore, the methodology used may help to improve knowledge on the regulation and resolution of inflammation.
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http://dx.doi.org/10.1186/1476-511X-9-129DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2988788PMC
November 2010

Induction of non-alcoholic fatty liver disease and insulin resistance by feeding a high-fat diet in rats: does coenzyme Q monomethyl ether have a modulatory effect?

Nutrition 2009 Nov-Dec;25(11-12):1157-68. Epub 2009 Jul 9.

Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore Sanità, Rome, Italy.

Objective: The aim of this study was to investigate the development of non-alcoholic fatty liver disease (NAFLD) in response to a high-fat diet in rats and to test the hypothesis that dietary coenzyme Q monomethyl ether (CoQme) has antisteatogenic effects.

Methods: Rats were fed a standard low-fat diet (control) for 18 wk or a diet containing 35% fat (57% metabolizable energy) for 10 wk, then divided into three groups for the following 8 wk. One group was given CoQ9me (30mg/kg body weight per day in 0.3mL olive oil: high fat+CoQ9me), the second olive oil (0.3mL/d) only (high fat + olive oil), and the third group received no supplements (high fat).

Results: Insulin levels and the activity of alanine aminotransferase in the plasma were significantly increased in all high-fat diet groups, and the homeostasis model assessment of insulin resistance indicated insulin resistance. Triacylglycerol concentrations in whole plasma and in very low-density lipoprotein and low-density lipoprotein fractions were also raised. Liver histology showed lipid accumulation in animals fed the high-fat diets, and liver triacylglycerol levels were increased (2.5- to 3-fold) in all high-fat diet groups. These effects were not changed by the administration of CoQ9me.

Conclusions: Rats fed a diet with 57% energy from fat showed insulin resistance, hypertriglyceridemia, increased very low-density lipoprotein production, hepatic steatosis, and liver damage, and thus provide a good model for the early stages of NAFLD. Dietary CoQ9me, however, did not ameliorate the damaging effects of the high-fat diet.
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http://dx.doi.org/10.1016/j.nut.2009.02.009DOI Listing
February 2010

Neutrophil generation of inflammatory precursors is not modulated by docosahexaenoic acid.

Inflamm Res 2009 Oct 31;58(10):677-85. Epub 2009 Mar 31.

Department of Pediatrics, Centro di Riferimento Fibrosi Cistica Regione Lazio, Università La Sapienza, Viale Regina Elena 324, 00161, Rome, Italy.

Objective And Design: It is believed that correction of membrane fatty acid deficiency in cystic fibrosis (CF) downregulates the synthesis of proinflammatory mediators. We tested the hypothesis that an increase of the proportion of docosahexaenoic acid (DHA) in the membrane in vitro changes the neutrophil response to Pseudomonas aeruginosa lipopolysaccharide (LPS).

Results: Treatment with DHA increased the secretion of interleukin(IL)-1|*alpha*| by CF neutrophils, but the secretion of other cytokines, CD11b expression, and arachidonic acid (AA) release were not affected either in CF or control (CT) neutrophils. Both with and without DHA, only one out of eight CF neutrophils responded to LPS with an increase of released AA, while five out of seven CT cells released more AA (CF vs. CT P < 0.05 by Fisher test).

Conclusions: These results indicate that in neutrophils the beneficial effects of DHA on immune response are not directly related to the generation of proinflammatory precursors, and suggest that in CF the lower neutrophil AA generation in response to activation could cause insufficient production of lipid mediators involved in the resolution of lung inflammation.
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http://dx.doi.org/10.1007/s00011-009-0035-5DOI Listing
October 2009

Ocimum basilicum ethanolic extract decreases cholesterol synthesis and lipid accumulation in human macrophages.

Fitoterapia 2008 Dec 22;79(7-8):515-23. Epub 2008 Jun 22.

Department of Haematology and Medicine Molecular, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Roma, Italy.

Macrophage lipid accumulation induced by low density lipoproteins (LDL) plays a pivotal role in atherosclerotic plaque development. Previous work showed that Ocimum basilicum extract, used as hypocholesterolemic agent by traditional medicine in Morocco, has hypolipidemic activity in rat acute hyperlipimidemia. This study investigated the effects of ethanolic extract of O. basilicum on lipid accumulation in human macrophages. As modification of LDL increase atherogenicity of the particles we evaluated the effects of the extract on LDL oxidation. The extract caused a dose-related increase of LDL-resistance to Cu(2+)-induced oxidation. Furthermore, at the dose of 60 microg/ml, significantly decreases the accumulation of macrophage lipid droplets induced by modified LDL evaluated as by red-oil staining. Cholesterol esterification and triacylglycerol synthesis in the cells were not affected. Macrophage treatment with 60 microg/ml, but not 20 microg/ml, of the extract reduced newly synthesized unesterified cholesterol by about 60% and decreased scavenger receptors activity by about 20-30%, evaluated by the internalization of cholesterol carried by [(3)H]CE-aggregated-LDL. The results suggest that O. basilicum ethanolic extract has the capability to reduce foam cell formation through the reduction of cholesterol synthesis and the modulation of the activity of surface scavenger receptors.
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http://dx.doi.org/10.1016/j.fitote.2008.05.002DOI Listing
December 2008

Effects of lycopene on the induction of foam cell formation by modified LDL.

Am J Physiol Endocrinol Metab 2007 Dec 2;293(6):E1820-7. Epub 2007 Oct 2.

Istituto Superiore di Sanitá, Dept. of Haematology, Oncology and Molecular Medicine, Viale Regina Elena 299, 00161 Rome, Italy.

The effect of lycopene on macrophage foam cell formation induced by modified low-density lipoprotein (LDL) was studied. Human monocyte-derived macrophages (HMDM) were incubated with lycopene in the presence or absence of native LDL (nLDL) or LDL modified by oxidation (oxLDL), aggregation (aggLDL), or acetylation (acLDL). The cholesterol content, lipid synthesis, scavenger receptor activity, and the secretion of inflammatory [interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha] and anti-inflammatory (IL-10) cytokines was determined. Lycopene was found to decrease the synthesis of cholesterol ester in incubations without LDL or with oxLDL while triacylglycerol synthesis was reduced in the presence of oxLDL and aggLDL. Scavenger receptor activity as assessed by the uptake of acLDL was decreased by approximately 30% by lycopene. In addition, lycopene inhibited IL-10 secretion by up to 74% regardless of the presence of nLDL or aggLDL but did not affect IL-1beta or TNF-alpha release. Lycopene also reduced the relative abundance of mRNA transcripts for scavenger receptor A (SR-A) in THP-1 macrophages treated with aggLDL. These findings suggest that lycopene may reduce macrophage foam cell formation induced by modified LDL by decreasing lipid synthesis and downregulating the activity and expression of SR-A. However, these effects are accompanied by impaired secretion of the anti-inflammatory cytokine IL-10, suggesting that lycopene may also exert a concomitant proinflammatory effect.
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http://dx.doi.org/10.1152/ajpendo.00315.2007DOI Listing
December 2007

Effects of new combinative antioxidant FeAOX-6 and alpha-tocotrienol on macrophage atherogenesis-related functions.

Vascul Pharmacol 2007 Jun 1;46(6):394-405. Epub 2007 Feb 1.

Department of Haematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Rome, Italy.

Pivotal role in atherogenesis is played by macrophages, which are early site for lipid accumulation and mediate the inflammatory and immune response in the intima. Epidemiological evidence indicates that natural antioxidants reduce the risk of heart disease, but, so far, supplementation studies have failed to confirm any protective effects of these compounds against cardiovascular disease. This study evaluated the effects of the natural antioxidant alpha-tocotrienol and of the newly designed compound, FeAOX-6, which combines antioxidant structural features of both tocopherols and carotenoids into a single molecule, on macrophage functions involved in foam cell formation. FeAOX-6 or alpha-tocotrienol induce a strong dose-dependent reduction of cholesterol and reduce cholesterol accumulation in human macrophages. The extent of the reduction found with alpha-tocotrienol was greater than that induced by FeAOX-6 and did not correlate with their respective antioxidant capacities. Treatment of HMDM with alpha-tocotrienol or FeAOX-6 enhanced also tumor necrosis factor-alpha secretion. These results are consistent with a reduction in scavenger receptor activity, but we found that antioxidant treatment did not affect cholesterol uptake from modified LDL. The effects on release on pro-inflammatory prostanoid precursors, PGE(2) and cytokine suggest a variety of metabolic responses that are both dependent on antioxidant compounds and macrophages activation status.
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http://dx.doi.org/10.1016/j.vph.2006.01.019DOI Listing
June 2007

Incorporation of lycopene into chylomicron remnant-like particles inhibits their uptake by HepG2 cells.

Life Sci 2007 Apr 3;80(18):1699-705. Epub 2007 Feb 3.

Department of Veterinary Sciences, The Royal Veterinary College, London, UK.

The influence of the incorporation of the antioxidant tomato pigment, lycopene, into chylomicron remnant-like particles (CRLPs) on their uptake by the liver cells was investigated. CRLPs or CRLPs containing lycopene (lycCRLPs) radiolabelled with [(3)H]triacylglycerol were incubated with cells of the human liver hepatoma cell line, HepG2, and the radioactivity taken up by the cells was determined. LycCRLPs were taken up significantly more slowly than CRLPs over a concentration range of 5-60 microg cholesterol/ml and a time course of 2-6 h. Pre-incubation of the hepatocytes with an excess of low density lipoprotein (LDL) inhibited the uptake of CRLPs by about 50%, but had no effect on the uptake of lycCRLPs, and under these conditions the CRLPs and lycCRLPs were taken up at similar rates. In HepG2 cells pre-treated with suramin, which inhibits uptake via the LDL receptor-related protein (LRP), the uptake of CRLPs was also inhibited (-37%) to a greater extent than that of lycCRLPs (-24%), so that the values for the two types of particle were no longer significantly different. Heparinase increased the uptake of lycCRLPs (about 2 fold), but not CRLPs, bringing it to a level equivalent to that seen with the control particles. These findings demonstrate that the incorporation of lycopene into CRLPs decreases their uptake by HepG2 cells and suggest that this effect is due to differential interaction with the LDL receptor and the LRP-receptor-mediated pathways, and may also involve binding of the particles to HSPG.
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http://dx.doi.org/10.1016/j.lfs.2007.01.051DOI Listing
April 2007

Very low density lipoprotein and low density lipoprotein isolated from patients with hepatitis C infection induce altered cellular lipid metabolism.

J Med Virol 2007 Mar;79(3):254-8

Department of Haematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy.

Several abnormalities of lipid metabolism, including hypo-beta-lipoproteinemia and liver steatosis are associated with infection by hepatitis C virus (HCV). The aim of this study was to determine whether circulating lipoproteins of patients with HCV infection could directly cause alterations of lipid cellular metabolism. To this end the metabolic response of human monocyte-derived macrophages (HMDM) to very low-density lipoprotein (VLDL) and low-density lipoprotein (LDL), measuring the cholesteryl ester (CE) and triglyceride (TG) production was analyzed. Lipoproteins were isolated from 18 patients infected with hepatitis C virus (HCV-VLDL and HCV-LDL) and from normal healthy donors (ct-VLDL and ct-LDL). In comparison to ct-lipoproteins, HCV-lipoproteins induced significant differences in HMDM CE and TG production. HCV-VLDL decreased CE and TG production; while HCV-LDL induced an increased TG synthesis. The present findings suggest that HCV infection modifies VLDL and LDL molecular composition, affecting cellular lipid metabolism, thus promoting intracellular lipid accumulation and hypo-beta-lipoproteinemia.
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http://dx.doi.org/10.1002/jmv.20793DOI Listing
March 2007

Hypolipidaemic activity of aqueous Ocimum basilicum extract in acute hyperlipidaemia induced by triton WR-1339 in rats and its antioxidant property.

Phytother Res 2006 Dec;20(12):1040-5

Department of Biology, Faculty of Sciences, University Mohamed I, Oujda, Morocco.

Hyperlipidaemia, atherosclerosis and related diseases are becoming a major health problem in developing countries. Ocimum basilicum is one of the medicinal plants widely used in Morocco to reduce plasma cholesterol and to reduce the risk of atherosclerosis-related diseases. However, mechanisms underlying the reported hypolipidaemic effect of this plant have not been investigated. This study evaluates the lipid lowering effect of aqueous Ocimum basilicum extract in Triton WR-1339-induced hyperlipidaemic rats. Hyperlipidaemia was developed in animals by intraperitoneal injection of Triton (200 mg/kg). After injection of Triton the animals were divided into three treatment groups: hyperlipidaemic, hyperlipidaemic plus herb extract and hyperlipidaemic plus fenofibrate treated rats. At 7 h after the Triton injection, levels of plasma cholesterol, triglycerides and LDL-cholesterol in rats treated also with the Ocimum basilicum extract (0.5 g/100 g body weight) were, respectively, 50%, 83% and 79% lower than Triton-treated rats and HDL-cholesterol was 129% higher than in rats given Triton alone. At 24 h following Ocimum basilicum administration, total cholesterol, triglycerides and LDL-cholesterol levels decreased by 56%, 63% and 68%, respectively, in comparison with the Triton treated group and HDL-cholesterol was not increased significantly. The hypolipidaemic effect exerted by Ocimum basilicum extract was markedly stronger than the effect induced by fenofibrate treatments. Further it was demonstrated that Ocimum basilicum aqueous extract displayed a very high antioxidant power. These results indicate that Ocimum basilicum extract may contain hypolipidaemic and antioxidant substances and its use as a therapeutic tool in hyperlipidaemic subjects may be of benefit and encourage further investigation in this field.
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http://dx.doi.org/10.1002/ptr.1961DOI Listing
December 2006

Evidence of dual pathways for lipid uptake during chylomicron remnant-like particle processing by human macrophages.

J Vasc Res 2006 21;43(4):355-66. Epub 2006 Jun 21.

Department of Haematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy.

Background: Though it is now clear that chylomicron remnants are pro-atherogenic lipoproteins, events leading to their incorporation by macrophages are poorly understood.

Methods: This study investigates, in human macrophages, the fate of either [(3)H]cholesteryl oleate or [(3)H]triacylglycerol carried by human apolipoprotein-E-containing chylomicron remnant-like particles (CRLP) and the influence of CRLP containing trilinolein, (18:2)CRLP, or triolein, (18:1)CRLP, on lipid accumulation, newly synthesized cholesteryl ester (CE) and triacylglycerol (TG).

Results: Labelled fatty acids from TG were markedly incorporated into TG and phospholipid and, to a lesser extent, into free fatty acids and were scarcely recovered in cholesteryl esters. [(3)H]CE from CRLP accumulated in cells in a dose-dependent manner with a significant difference between concentrations of 10 and 40 microg cholesterol/ml with (18:2)CRLP. In the same concentration range, TG synthesis was enhanced by about 46 and 30% by (18:2)CRLP and (18:1)CRLP cholesterol, respectively, whereas the esterification of cholesterol, evaluated by [(3)H]oleate incorporation, was decreased by about 30% with both types of CRLP. Endocytosis inhibition did not prevent cell cholesterol and TG accumulation, whereas lipoprotein lipase inhibition reduced the TG content.

Conclusions: The results are consistent with the hypotheses that in macrophages dietary remnants may support TG and CE internalization via different mechanisms. Extracellular lipolysis seems particularly important for internalization of dietary fatty acids, whereas the entrance of CE seems attributable to a concomitant selective CE uptake mediated by scavenger receptor class B type I, since the scavenger receptor class B type I antibody induces significant inhibition (38%) of [(3)H]CE transported by CRLP, but does not affect internalization of [(3)H]TG carried by the same particles.
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http://dx.doi.org/10.1159/000094095DOI Listing
August 2006

Cholesterol esterification in human monocyte-derived macrophages is inhibited by protein kinase C with dual roles for mitogen activated protein kinases.

Cell Biol Int 2004 ;28(10):717-25

Istituto Superiore di Sanita, Department of Hematology, Oncology and Molecular Medicine, Viale Regina Elena, 00161 Rome, Italy.

The possible role of protein kinase C (PKC) and mitogen activated protein (MAP) kinases in the stimulation of cholesterol esterification by acetylated low density lipoprotein (acLDL) in human monocyte-derived macrophages (HMDM) was studied. Cholesterol esterification, as assessed by the rate of incorporation of [3H]-oleate into cholesteryl ester, was markedly higher in HMDM incubated with acLDL as compared to native LDL (nLDL). In the presence of the phorbol ester, phorbol 12-myristate 13-acetate (PMA, 100 nM), however, the rate of incorporation was reduced by about 50% and 85% in incubations with nLDL and acLDL, respectively. Thus, the difference in the rate of cholesteryl esterification induced by the two types of lipoprotein was abolished by PMA, indicating that PKC activation inhibits the process, and this was confirmed by the finding that the PKC inhibitor calphostin C reversed the PMA-induced inhibition of cholesterol esterification. Incubation of HMDM with PMA was found to cause a considerable increase in the activation of p42/44 extracellular signal-regulated MAP kinases (ERK) and p38 MAP kinases, reaching a maximum at 30 min. In the presence of acLDL, the ERK inhibitor PD98059 decreased cholesterol esterification in HMDM by about 35%. In contrast, the p38 inhibitor SB203580 had no effect. However, when PMA was present in addition to SB203580, esterification was reduced to a level lower than that observed with PMA alone. These findings suggest that activation of ERK, but not p38, MAP kinases is involved in the induction of cholesterol esterification by acLDL in HMDM, while p38 MAP kinases may modulate the inhibitory effect of PKC, and thus provide evidence that MAP kinases play a role in the regulation of foam cell formation in human macrophages.
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http://dx.doi.org/10.1016/j.cellbi.2004.07.007DOI Listing
March 2005

Protection of chylomicron remnants from oxidation by incorporation of probucol into the particles enhances their uptake by human macrophages and increases lipid accumulation in the cells.

Eur J Biochem 2004 Jun;271(12):2417-27

Department of Veterinary Basic Sciences, The Royal Veterinary College, London, UK.

The effects of protection of chylomicron remnants from oxidation on their uptake and induction of lipid accumulation in macrophages were investigated using chylomicron remnant-like particles (CRLPs) containing the lipophilic antioxidant drug, probucol, and macrophages derived from the human monocyte cell line, THP-1. The total lipid content of THP-1 macrophages was markedly higher (x2.2) after 48 h of incubation of THP-1 macrophages with CRLPs containing probucol (pCRLPs) when compared to CRLPs without probucol, and this was because of increases in triacylglycerol (x2.3) and cholesterol (x1.8) levels, while cholesteryl ester concentrations were not significantly changed. Determination of the uptake of CRLPs and pCRLPs by the cells using particles labelled with the fluorescent probe 1,1'-dioctadecyl-3,3,3'3'-tetramethylindo-carbocyanine perchlorate showed that pCRLPs are taken up at a faster rate than CRLPs. The synthesis of triacylglycerol, as measured by the incorporation of [(3)H]oleate and [(3)H]glycerol, was also increased in macrophages incubated with pCRLPs as compared to CRLPs without probucol, but phospholipid and cholesteryl ester formation from [(3)H]oleate was unaffected. In addition, no differences between the effects of CRLPs and pCRLPs on the expression of mRNA for a range of genes believed to be involved in lipoprotein uptake, intracellular lipid metabolism and the efflux of cholesterol from macrophages was detected. These results suggest that antioxidants carried in chylomicron remnants enhance lipid accumulation in macrophages by increasing the rate of uptake of the particles and raising the intracellular synthesis of triacylglycerol, but not cholesteryl ester, and that these effects are brought about by changes at the post-transcriptional level. Antioxidants carried in chylomicron remnants therefore may promote the development of atherosclerosis, and this is likely to be particularly important in conditions where clearance of remnants from the circulation is delayed.
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http://dx.doi.org/10.1111/j.1432-1033.2004.04164.xDOI Listing
June 2004

Differential control of cholesterol and fatty acid biosynthesis in sensitive and multidrug-resistant LoVo tumor cells.

Anticancer Res 2003 Nov-Dec;23(6C):4737-46

Laboratorio di Ultrastrutture, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161, Rome, Italy.

Multidrug resistance (MDR) describes the decrease in sensitivity of tumor cells to a wide variety of cytotoxic compounds. Although a central role has been ascribed to the P-glycoprotein (Pgp) pump in MDR, lipids also appear to be extremely important. However, their precise role in MDR is not yet fully understood. It was the aim of the present paper to gain a deeper understanding of intracellular lipid equilibrium in both sensitive and MDR tumor cells. In particular, intracellular cholesterol biosynthesis and cholesterol esterification were examined in LoVo-sensitive and Pgp-overexpressing resistant cells. The data presented seem to suggest that the higher synthesis of cholesteryl ester and triglyceride observed in resistant with respect to wild-type cells is due to a greater production of fatty acids in these cells. The results are discussed in view of the possible roles of sterol regulatory element-binding proteins and Pgp in these phenomena.
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April 2004

Incorporation of lycopene into chylomicron remnant-like particles enhances their induction of lipid accumulation in macrophages.

Biochem Biophys Res Commun 2003 Dec;312(4):1216-9

Department of Veterinary Basic Sciences, The Royal Veterinary College, Royal College St., NW1 0TU, London, UK.

Lipid accumulation in macrophages exposed to chylomicron remnant-like particles containing the dietary antioxidant lycopene was investigated. After incubation with THP-1 macrophages (48h), chylomicron remnant-like particles containing lycopene (lycCRLPs) as compared to those without (CRLPs) caused significantly more lipid accumulation in the cells, and this was due to increases in both the triacylglycerol (+100%) and cholesterol (+62%) content. In addition, expression of mRNA for diacylglycerol acyltransferase (DGAT), a key enzyme in triacylglycerol synthesis, was significantly decreased by lycCRLPs, but not CRLPs. These findings suggest that lycopene from the diet may promote, rather than retard, lipid accumulation in macrophages during its transport in the blood in chylomicron remnants.
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http://dx.doi.org/10.1016/j.bbrc.2003.11.040DOI Listing
December 2003

Influence of thiol balance on micellar cholesterol handling by polarized Caco-2 intestinal cells.

FEBS Lett 2003 Sep;551(1-3):165-70

Laboratory of Metabolism and Pathological Biochemistry, Istituto Superiore di Sanità, 00161 Rome, Italy.

The in vitro thiol redox modulation of cholesterol homeostasis was investigated in polarized Caco-2 intestinal cells. Cells were pre-incubated with the pro-oxidant compound CuSO4 or with the antioxidant N-acetylcysteine (NAC), to induce a mild shift of the intracellular redox potential toward, respectively, a more oxidizing or a more reducing equilibrium, via a manipulation of intracellular soluble thiols (glutathione). Then, monolayers were exposed to micellar cholesterol and both the cholesterol uptake and export, as well as the cholesteryl ester cycle, were analyzed. We found that pro-oxidizing conditions induced a significant cholesterol retention within the cells, particularly in the unesterified form (FC), as a result of an augmented sterol incorporation coupled with a reduced rate of FC esterification. A reduction in FC export was also evident. Furthermore, the combination of FC retention and the oxidative imbalance leads to significant alterations of the monolayer integrity, evidenced by both the enhanced tight junction permeability and the lactate dehydrogenase release into the basolateral medium. In contrast, a more reducing environment generated by NAC pre-treatment favors the limitation of the resident time of FC into the cells, via a reduced cholesterol uptake and a concomitant increased cholesterol esterification. In addition, a significant higher FC extrusion into the basolateral medium was also appreciable. Our results indicate that the thiol balance of intestinal cells may be critical for the regulation of cholesterol homeostasis at the intestinal level, influencing the lipid transport throughout the intestinal barrier.
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http://dx.doi.org/10.1016/s0014-5793(03)00842-1DOI Listing
September 2003