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Calza DL, Manfredi R, Chiodo F. Cardiovascular risk associated with antiretroviral therapy in HIV-infected patients. Expert Opin Ther Pat 2006. [DOI: 10.1517/13543776.16.11.1497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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52
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Prot M, Heripret L, Cardot-Leccia N, Perrin C, Aouadi M, Lavrut T, Garraffo R, Dellamonica P, Durant J, Le Marchand-Brustel Y, Binétruy B. Long-term treatment with lopinavir-ritonavir induces a reduction in peripheral adipose depots in mice. Antimicrob Agents Chemother 2006; 50:3998-4004. [PMID: 17000748 PMCID: PMC1693995 DOI: 10.1128/aac.00625-06] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Highly active antiretroviral therapy (HAART) of human immunodeficiency virus-infected patients is associated with adverse effects, such as lipodystrophy and hyperlipidemia. The lipodystrophic syndrome is characterized by a peripheral lipoatrophy and/or fat accumulation in the abdomen and neck. In order to get insights into the physiopathological mechanisms underlying this syndrome, we treated mice with protease inhibitors (PIs) over a long period of time. Although atazanavir-treated mice presented the same circulating triglyceride concentration as control mice, lopinavir-ritonavir-treated mice rapidly became hypertriglyceridemic, with triglyceride levels of 200 mg/dl, whereas control and atazanavir-treated animals had triglyceride levels of 80 mg/dl. These results obtained with mice reproduce the metabolic disorder observed in humans. White adipose tissue (WAT) was analyzed after 8 weeks of treatment. Compared to the control or atazanavir treatment, lopinavir-ritonavir treatment induced a significant 25% weight reduction in the peripheral inguinal WAT depot. By contrast, the profound epididymal WAT depot was not affected. This effect was associated with a 5.5-fold increase in SREBP-1c gene expression only in the inguinal depot. Our results demonstrate that the long-term treatment of mice with PIs constitutes an interesting experimental model with which some aspects of the lipoatrophy induced by HAART in humans may be studied.
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53
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Lindegaard B, Larsen LF, Hansen ABE, Gerstoft J, Pedersen BK, Reue K. Adipose tissue lipin expression levels distinguish HIV patients with and without lipodystrophy. Int J Obes (Lond) 2006; 31:449-56. [PMID: 16847472 DOI: 10.1038/sj.ijo.0803434] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
OBJECTIVE Lipodystrophy is the major complication of antiretroviral therapy in HIV-infected patients. Its pathophysiology is not well understood, but has been linked to antiadipogenic effects of antiretroviral drugs. Lipin represents a newly characterized protein that is critical for adipocyte differentiation, and lipin deficiency leads to lipodystrophy in the mouse. The objective of this study was to determine whether altered lipin gene expression is associated with HIV lipodystrophy in humans. DESIGN We measured lipin mRNA levels in subcutaneous abdominal and femoral-gluteal adipose tissue biopsies from HIV-infected patients with or without lipodystrophy, and in healthy controls. Real-time reverse transcription-PCR was performed to quantitate total lipin expression levels, and expression of two lipin isoforms (lipin-alpha and -beta) that are generated by alternative mRNA splicing. RESULTS As predicted from studies with mice, lipin mRNA levels were correlated with limb fat mass in HIV patients, with lower lipin levels in patients with lipodystrophy than those without lipodystrophy. Unexpectedly, however, this was explained by an increase in lipin-beta expression in HIV patients without lipodystrophy compared to patients with lipodystrophy and control subjects. In addition, lipin expression levels were inversely correlated with adipose tissue expression of inflammatory cytokines interleukin (IL)-6, IL-8 and IL-18, which typically increase in HIV-associated lipoatrophy. CONCLUSIONS Elevated lipin expression levels are associated both with the maintenance of greater fat mass and lower cytokine expression in HIV-infected patients. Based on the demonstrated role for lipin in promoting lipogenic gene expression, these observations raise the possibility that variations in lipin levels may contribute to variations in adipose tissue mass and function that distinguish HIV patients with and without lipodystrophy.
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Affiliation(s)
- B Lindegaard
- Department of Infectious Diseases, The Centre of Inflammation and Metabolism, University of Copenhagen, Rigshospitalet, Copenhagen, Denmark
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54
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Kim RJ, Wilson CG, Wabitsch M, Lazar MA, Steppan CM. HIV protease inhibitor-specific alterations in human adipocyte differentiation and metabolism. Obesity (Silver Spring) 2006; 14:994-1002. [PMID: 16861604 DOI: 10.1038/oby.2006.114] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Human immunodeficiency virus (HIV) patients on antiretroviral regimens frequently develop a syndrome of abnormal fat distribution, insulin resistance, and dyslipidemia. This lipodystrophic syndrome has been most closely linked to the use of HIV protease inhibitors (PIs). Several mechanisms have been postulated to explain these adverse effects of PIs, based largely on studies of rodent adipocytes. Intriguingly, atazanavir, a newer PI equally effective against HIV, is associated with fewer signs of lipodystrophy. We hypothesized that the less deleterious clinical effects of atazanavir would be reflected in physiological differences observed in PI-treated adipocytes. RESEARCH METHODS AND PROCEDURES We compared the effects of atazanavir and an older PI associated with lipodystrophy, ritonavir, on differentiation, gene expression, adipocytokine secretion, and insulin signaling in a human adipocyte cell line. RESULTS Ritonavir inhibited human adipocyte differentiation and induced apoptosis to a greater extent than atazanavir. Treatment of mature adipocytes with ritonavir, but not atazanavir, also selectively decreased insulin signaling. Moreover, ritonavir also selectively decreased expression of adiponectin, an insulin-sensitizing adipocytokine, while inducing interleukin-6, a proinflammatory cytokine implicated in insulin resistance. DISCUSSION These data suggest that the distinct metabolic side effect profiles of these PIs could be a consequence of their differential effects on adipocyte physiology.
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Affiliation(s)
- Roy J Kim
- Division of Endocrinology, Children's Hospital of Philadelphia, Pennsylvania, USA
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55
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Abstract
An increasing number of cannabinoid actions are being reported that do not appear to be mediated by either CB1 or CB2, the known cannabinoid receptors. One such example is the synthetic analog ajulemic acid (AJA), which shows potent analgesic and anti-inflammatory effects in rodents and humans. AJA binds weakly to CB1 only at concentrations many fold higher than its therapeutic range, and is, therefore, completely free of psychotropic effects in both normal subjects and pain patients suggesting the involvement of a target site other than CB1. AJA as well as several other cannabinoids appear to have profound effects on cellular lipid metabolism as evidenced by their ability to transform fibroblasts into adipocytes where the accumulation of lipid droplets can be readily observed. Such transformations can be mediated by the activation of the nuclear receptor PPAR-gamma. A variety of small molecule ligands including AJA have been shown to induce the activation of PPAR-gamma and, in some cases this has led to the introduction of clinically useful agents. It is suggested that PPAR-gamma may serve a receptor function for certain actions of some cannabinoids.
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Affiliation(s)
- Sumner Burstein
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation St., Worcester, MA 01605-2324, USA.
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56
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Abstract
Obesity and lipoatrophy are major risks for insulin resistance, non-insulin-dependent diabetes and cardiovascular disease. In the past three decades, significant advances have been made in delineating the key transcription factors of adipogenesis, as well as extracellular effectors and intracellular signalling pathways that regulate fat cell formation. This review focuses on in vitro models of adipocyte differentiation, and on the balance between pro- and anti-adipogenic factors that drive the adipocyte differentiation process. Full understanding of the mechanisms of adipose tissue differentiation represents a major issue to develop a comprehensive strategy to prevent and treat obesity.
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Affiliation(s)
- Bruno Fève
- INSERM U693, Faculté de Médecine de Bicêtre, 63 rue Gabriel Péri, 94270 Le Kremlin-Bicêtre, France.
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57
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Lagathu C, Kim M, Maachi M, Vigouroux C, Cervera P, Capeau J, Caron M, Bastard JP. HIV antiretroviral treatment alters adipokine expression and insulin sensitivity of adipose tissue in vitro and in vivo. Biochimie 2005; 87:65-71. [PMID: 15733739 DOI: 10.1016/j.biochi.2004.12.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2004] [Accepted: 12/20/2004] [Indexed: 12/01/2022]
Abstract
HIV-1-infected patients on antiretroviral therapy frequently develop a lipodystrophy syndrome, characterized by peripheral lipoatrophy and visceral fat redistribution associated with metabolic alterations including dyslipidemia and insulin resistance. Its pathophysiology remains unclear but the antiretroviral treatment, associating protease inhibitors (PIs) and nucleoside analogue inhibitors of the viral reverse transcriptase (NRTIs), plays a major role. Some antiretroviral molecules inhibit differentiation and induce insulin resistance and apoptosis in adipose cells both in vitro and in vivo. In vitro, PIs and NRTIs increase the expression and secretion of pro-inflammatory cytokines such as TNF alpha, IL-6 and L-1beta, which are involved in altered adipocyte functions and decrease that of adiponectin, a positive modulator of insulin sensitivity. Similar alterations are observed in fat and serum from HIV-1-infected lipodystrophic patients under antiviral treatment associating PIs and NRTIs. Altered adipokine secretion could result from patients' exposure to PIs and NRTIs and lead to altered adipocyte differentiation, insulin resistance and apoptosis, ultimately resulting in lipoatrophy. These disorders probably result in a decreased secretion of adiponectin and an increased release of free fatty acids by insulin-resistant adipose tissue. Therefore, they could be involved in whole body insulin resistance and metabolic alterations in lipodystrophic HIV-1-infected patients.
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Affiliation(s)
- Claire Lagathu
- Inserm U.680 and IFR65, Université Pierre et Marie Curie, Faculté de Médecine Saint-Antoine, 27, rue Chaligny, 75571 Paris cedex 12, France
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58
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Adler-Wailes DC, Liu H, Ahmad F, Feng N, Londos C, Manganiello V, Yanovski JA. Effects of the human immunodeficiency virus-protease inhibitor, ritonavir, on basal and catecholamine-stimulated lipolysis. J Clin Endocrinol Metab 2005; 90:3251-61. [PMID: 15741249 PMCID: PMC1350765 DOI: 10.1210/jc.2004-2194] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Several of the aspartic acid protease inhibitors used to treat HIV infection increase basal lipolysis in adipocytes, but the cellular mechanisms leading to this augmentation are not well understood. We therefore studied the effects of chronic exposure to the HIV protease inhibitor, ritonavir, on the lipolytic cascade in 3T3-L1 adipocytes. Treatment of 3T3-L1 adipocytes with ritonavir for 14 d (during and after differentiation) enhanced basal, isoproterenol (Iso)-stimulated, and cAMP analog-stimulated lipolysis. Enhancement of lipolysis was observed after Iso at concentrations between 0.1 and 10 mum. Despite a significant decrease in cyclic nucleotide phosphodiesterase (PDE)3B activity and protein levels, there were no changes in Iso-stimulated intracellular cAMP, protein kinase A (PKA) expression, or PKA activity. Ritonavir-augmented lipolysis was also observed under conditions that reversed the effect on PDE3B activity via preincubation with 1 mum (-)-N(6)-(2-phenylisopropyl)adenosine. In ritonavir-treated cells, protein expression of the lipid droplet-protective protein, perilipin, was significantly decreased, whereas there was no change in hormone-sensitive lipase. Activation of ERK1/2 by Iso did not play a role in the augmentation. We conclude that ritonavir decreases PDE3B and perilipin protein expression and affects both basal and catecholamine-stimulated lipolysis in 3T3-L1 adipocytes primarily through actions at sites downstream of PKA.
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Key Words
- ap-2, adipocyte fatty acid binding protein
- cat-α, catalytic-α
- dmso, dimethylsulfoxide
- fbs, fetal bovine serum
- haart, highly active antiretroviral therapy
- hsl, hormone-sensitive lipase
- ibmx, isobutylmethylxanthine
- iso, isoproterenol
- krh, krebs/ringer/hepes
- nefa, nonesterified fatty acid
- pde, phosphodiesterase
- peri, perilipin
- pia, (-)-n6-(2-phenylisopropyl)adenosine
- pka, protein kinase a
- pki, protein kinase inhibitor
- sds, sodium dodecyl sulfate
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Affiliation(s)
| | | | | | | | | | | | - Jack A. Yanovski
- Address all correspondence and requests for reprints to: Jack A. Yanovski, National Institutes of Health, Clinical Research Center, Room 1–3330, 10 Center Drive, MSC-1103, Bethesda, Maryland 20892-1103. E-mail:
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59
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Abstract
PURPOSE OF REVIEW The purpose of this review is to summarize recent data on treatment options for highly active antiretroviral therapy-associated lipoatrophy. RECENT FINDINGS Modification of antiretroviral therapy, especially replacing stavudine by abacavir, induces a slow but continuous increase in the subcutaneous fat mass in patients with highly active antiretroviral therapy-associated lipoatrophy. As part of an initial highly active antiretroviral therapy combination, tenofovir and emtricitabine cause less lipodystrophy than stavudine, but no data from controlled studies have yet assessed the effects of switching from older agents to tenofovir or emtricitabine. Novel antidiabetic drugs, glitazones, cause little improvement in highly active antiretroviral therapy-associated lipoatrophy, but increase blood cholesterol and triglyceride concentrations significantly, and thus cannot be recommended for the treatment of highly active antiretroviral therapy-associated lipoatrophy. Various reconstructive procedures have been used to correct facial lipoatrophy. Bioabsorbable fillers have been used successfully, but treatment with such fillers has to be repeated over time. Permanent fillers have a durable effect, but may be difficult or impossible to remove if complications occur. Furthermore, an optimal volume correction with a permanent filler now may prove to be an over-correction in the future, if the recovery process of adipose tissue continues after the modification of antiretroviral therapy. SUMMARY The optimal choice of antiretroviral combination is of crucial importance for the prevention and treatment of highly active antiretroviral therapy-associated lipoatrophy. Switching from stavudine to abacavir causes a slow but continuous increase in the subcutaneous fat mass. Bioabsorbable skin fillers are the safest option for the reconstructive treatment of facial lipoatrophy.
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Affiliation(s)
- Jussi Sutinen
- Department of Medicine, Division of Infectious Diseases, Helsinki University Central Hospital, Helsinki, Finland.
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Dowell P, Lane MD. C/EBPα reverses the anti-adipogenic effects of the HIV protease inhibitor nelfinavir. Biochem Biophys Res Commun 2005; 327:571-4. [DOI: 10.1016/j.bbrc.2004.11.169] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Indexed: 10/26/2022]
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61
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Abstract
Most, if not all, drugs interact with multiple proteins. One or more of these interactions are responsible for carrying out the primary therapeutic effects of the drug. Others are involved in the transport or metabolic processing of the drug or in the mediation of side effects. Still others may be responsible for activities that correspond to alternate therapeutic applications. The potential clinical impact of a drug and its cost of development are affected by the sum of all these interactions. The drug development process includes the identification and characterisation of a drug's clinically relevant interactions. This characterisation is presently accomplished by a combination of experimental laboratory techniques and clinical trials, with increasing numbers of patient participants. Efficient methods for the identification of all the molecular targets of a drug prior to clinical trials could greatly expedite the drug development process. Combinatorial peptide and cDNA phage display have the potential for achieving a complete characterisation of the binding repertoire of a small molecule. This paper will discuss the current state of phage display technology, as applied to the identification of novel receptors for small molecules, using a successful application with the drug Taxol™ as an example of the technical and theoretical benefits and pitfalls of this method.
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Affiliation(s)
- Lee Makowski
- Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
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62
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Affiliation(s)
- Steven Grinspoon
- Program in Nutritional Metabolism and the Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston 02114, USA.
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63
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Rudich A, Ben-Romano R, Etzion S, Bashan N. Cellular mechanisms of insulin resistance, lipodystrophy and atherosclerosis induced by HIV protease inhibitors. ACTA ACUST UNITED AC 2005; 183:75-88. [PMID: 15654921 DOI: 10.1111/j.1365-201x.2004.01383.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Accumulating clinical evidence now links HIV protease inhibitors (HPIs) to the pathogenesis of insulin resistance, dyslipidaemia, lipodystrophy and atherosclerosis associated with highly active anti-retroviral therapy. Here we briefly describe the evidence for a distinct causative role for HPIs, and explore the cellular mechanisms proposed to underlie these side-effects. Acute inhibition of GLUT4-mediated glucose transport, and defective insulin signalling induced by chronic exposure to nelfinavir, are described as cellular mechanisms of insulin resistance. Interference with adipogenesis and adipocyte apoptosis and nelfinavir-induced activation of lipolysis are discussed as potential mechanisms of HPI-induced lipodystrophy. HPI-induced free radical production, apoptosis and increased glucose utilization in vascular smooth muscle cells are presented as possible novel mechanisms for atherosclerosis. Common pathways and cause-effect relationships between the various cellular mechanisms presented are then discussed, with emphasis on the role of insulin resistance, free radical production and enhanced lipolysis. Understanding the cellular mechanisms of HPI-induced side-effects will enhance the search for improved anti-retroviral therapy, and may also shed light on the pathogenesis of common forms of insulin resistance, dyslipidaemia and atherosclerosis.
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Affiliation(s)
- A Rudich
- Department of Clinical Biochemistry, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84103, Israel
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64
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Vincent S, Tourniaire F, El Yazidi CM, Compe E, Manches O, Plannels R, Roche R. Nelfinavir Induces Necrosis of 3T3F44-2A Adipocytes by Oxidative Stress. J Acquir Immune Defic Syndr 2004; 37:1556-62. [PMID: 15577407 DOI: 10.1097/00126334-200412150-00003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Protease inhibitor treatment strongly diminishes mortality in HIV-infected patients. This treatment has also been associated with lipodystrophy and has been shown to alter adipocyte differentiation. The protease inhibitor nelfinavir has been indirectly implicated in the appearance and development of lipodystrophic syndrome, as well as in adipocyte cell death. The aim of this study was to evaluate the effects of nelfinavir on the 3T3-F442A adipocyte cell line. Nelfinavir (30 microM) induced cell death of 3T3-F442A adipocytes by a necrotic process that was not mediated by TNF-alpha. Treatment of cells with this protease inhibitor led to a significant increase in expression of the heme oxygenase-1 gene that could be reduced by 100 microM of the antioxidant ascorbate. Moreover, ascorbate had a protective effect on nelfinavir-induced necrosis, decreasing the percentage of necrotic cells by 70%. Our results show that nelfinavir induces necrosis of adipocytes mediated by a cellular increase of reactive oxygen species. This deleterious effect could be counterbalanced by ascorbate.
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65
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Bourlier V, Zakaroff-Girard A, De Barros S, Pizzacalla C, de Saint Front VD, Lafontan M, Bouloumié A, Galitzky J. Protease inhibitor treatments reveal specific involvement of matrix metalloproteinase-9 in human adipocyte differentiation. J Pharmacol Exp Ther 2004; 312:1272-9. [PMID: 15537822 DOI: 10.1124/jpet.104.077263] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We previously showed that human and murine 3T3-F442A preadipocytes produced and released matrix metalloproteinases (MMPs) 2 and 9 and that a treatment by MMP inhibitors resulted in the blockade of murine fat cell adipose conversion. In parallel, investigators reported that other protease inhibitors, the human immunodeficiency virus (HIV) protease inhibitors (PIs) involved in lipodystrophy in humans, also reduced the adipocyte differentiation process of several murine cell lines. The present work was performed to define the effects of MMP inhibitors and HIV-PIs on the human adipocyte differentiation process, to clarify the involvement of MMPs in the control of human adipogenesis, and to determine whether HIV-PIs interact with MMPs in the control of this process. The effect of two MMP inhibitor and four HIV-PI treatments on the differentiation of primary culture human preadipocytes, as well as the putative relationships between HIV-PIs and MMP-2 and -9 expression, release, or activity were investigated. We showed that MMP inhibitors and HIV-PIs reduced the human adipocyte differentiation process as assessed by the decrease of cell protein and/or triglyceride contents and expression of fatty acid binding protein and hormone-sensitive lipase, two adipocyte markers. Unlike MMP inhibitors, HIV-PIs were devoid of any effect per se on recombinant MMP-2 and 9 activities but reduced the expression and release of MMP-9 by human preadipocytes. Thus, the present study indicates that the modulation of the extracellular matrix components through the production and/or activity of MMPs, and, more precisely, MMP-9 might be a key factor in the regulation of human adipose tissue development.
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Affiliation(s)
- Virginie Bourlier
- Institut National de la Santé et de la Recherche Médicale U586, 37 Allées Jules Guesde, 31073 Toulouse, France.
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Caron M, Auclair M, Lagathu C, Lombès A, Walker UA, Kornprobst M, Capeau J. The HIV-1 nucleoside reverse transcriptase inhibitors stavudine and zidovudine alter adipocyte functions in vitro. AIDS 2004; 18:2127-36. [PMID: 15577645 DOI: 10.1097/00002030-200411050-00004] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Nucleoside analogues are suspected of playing a role in peripheral fat loss in patients during long-term treatment with antiretroviral drugs. DESIGN AND METHODS We compared the long-term effects of stavudine (10 microM), zidovudine (1 muM), didanosine (10 microM), abacavir (4 microM), lamivudine (10 microM), and tenofovir (1 microM), near their maximum concentration values, on the differentiation, lipid accumulation, survival and mitochondrial function of differentiating 3T3-F442A and differentiated 3T3-L1 adipocytes. RESULTS None of the nucleoside reverse transcriptase inhibitors (NRTI) markedly altered the differentiation of 3T3-F442A cells, as shown by the unmodified percentage of cells with lipid droplets on day 7 and the expression of the early differentiation markers CCAAT/enhancer binding protein (C/EBP) beta (on day 2) and sterol regulatory element-binding protein. However, stavudine and zidovudine altered the lipid phenotype, decreasing the lipid content and expression of markers involved in lipid metabolism, namely C/EBPalpha, peroxisome proliferator-activated receptor gamma, adipocyte lipid binding protein 2, fatty acid synthase and acetyl-coenzyme A carboxylase. Stavudine and zidovudine, contrary to the other NRTI, drove 5-10% of 3T3-F442A cells towards apoptosis, and reduced the lipid content and survival of differentiated 3T3-L1 adipocytes. Stavudine and zidovudine increased mitochondrial mass by two to fourfold, and lowered the mitochondrial membrane potential (JC-1 stain) as did zalcitabine (0.2 microM). Co-treatment with zidovudine plus lamivudine, or zidovudine plus lamivudine and abacavir, did not increase the effect of zidovudine on cell viability or apoptosis. CONCLUSION The thymidine analogues stavudine and zidovudine decreased lipid content, mitochondrial activity, and adipocyte survival in vitro.
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Affiliation(s)
- Martine Caron
- INSERM U402, Faculté de Médecine Saint-Antoine, Université Pierre et Marie Curie, Paris, France.
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67
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Fredriksen J, Ueland T, Dyrøy E, Halvorsen B, Melby K, Melbye L, Skalhegg BS, Bohov P, Skorve J, Berge RK, Aukrust P, Frøland SS. Lipid-lowering and anti-inflammatory effects of tetradecylthioacetic acid in HIV-infected patients on highly active antiretroviral therapy. Eur J Clin Invest 2004; 34:709-15. [PMID: 15473896 DOI: 10.1111/j.1365-2362.2004.01410.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Highly active antiretroviral therapy (HAART) often leads to a dramatic improvement in clinical, viral and immunologic parameters in HIV-infected individuals. However, the emergence of long-term side-effects of HAART and in particular dylipidaemia is increasingly reported. Based on the potential lipid-lowering and immunomodulatory properties of tetradecylthioacetic acid (TTA) we examined whether TTA in combination with dietary intervention could modify lipid levels in peripheral blood in HIV-infected patients on HAART. MATERIALS AND METHODS Ten HIV-infected patients on protease inhibitor-based HAART with hyperlipidaemia followed a cholesterol-lowering diet throughout the study period (8 weeks). During the last 4 weeks of the study all patients received TTA (1 g qd) in addition to the cholesterol-lowering diet. RESULTS Our main and novel findings were: (i) TTA in combination with dietary intervention reduces total cholesterol, LDL cholesterol, triglycerides and LDL/HDL cholesterol in these patients, and a particularly suppressing effect was observed during the TTA phase regarding total cholesterol. (ii) During the TTA phase, the cholesterol-lowering effect was accompanied by a significant reduction in plasma levels of tumour necrosis factor alpha. (iii) Our studies in peripheral blood mononuclear cells from these patients and in the liver from wild-type mice receiving TTA suggest that the hypolipidaemic effects of TTA may involve up-regulation of scavenger and LDL-receptor expression. CONCLUSIONS Although few patients were studied, the present pilot study suggests that TTA combined with dietary intervention could be an interesting therapeutic approach in HIV-infected patients on HAART, potentially resulting in both hypolipidaemic and anti-inflammatory effects.
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68
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Sekhar RV, Jahoor F, Pownall HJ, Ballantyne CM, Balasubramanyam A. Cardiovascular implications of HIV-associated dyslipidemic lipodystrophy. Curr Atheroscler Rep 2004; 6:173-9. [PMID: 15068741 DOI: 10.1007/s11883-004-0029-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The emergence of a new metabolic syndrome in patients with HIV infection, termed "HIV-associated dyslipidemic lipodystrophy" (HADL), is characterized by central fat redistribution, severe dyslipidemia, and insulin resistance and predisposes to an increased risk of cardiovascular disease. The factors promoting the development of cardiovascular disease in this condition are not well understood and may involve contributions from antiretroviral drugs and components of the HIV virus, as well as inflammatory cytokines, leading to accelerated lipolysis, dyslipidemia, lipotoxic insulin resistance, and vascular inflammation. In this article, we review HADL in terms of metabolic, molecular, and cytokine derangements leading to cardiovascular disease.
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Affiliation(s)
- Rajagopal V Sekhar
- Division of Endocrinology, Baylor College of Medicine, 719E, One Baylor Plaza, Houston, TX 77030, USA
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69
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Monier PL, Wilcox R. Metabolic complications associated with the use of highly active antiretroviral therapy in HIV-1-infected adults. Am J Med Sci 2004; 328:48-56. [PMID: 15254441 DOI: 10.1097/00000441-200407000-00007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The availability of highly active antiretroviral therapy (HAART) has resulted in dramatic declines in morbidity and mortality in patients infected with human immunodeficiency virus-1 (HIV-1). However, the success of HAART has been tempered by the recognition of adverse metabolic effects clearly associated with its use. These "metabolic complications" include dyslipidemia, changes in body fat distribution, insulin resistance and glucose intolerance, metabolic bone disease, and lactic acidosis. Guidelines to assist clinicians in the management of these complications have been put forth by various organizations, including the International AIDS Society, the HIV Medicine Association of the Infectious Disease Society of America, and the Adult AIDS Clinical Trials Group.
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Affiliation(s)
- Paul L Monier
- Louisiana State University Health Sciences Center, New Orleans 70112, USA.
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Lagathu C, Bastard JP, Auclair M, Maachi M, Kornprobst M, Capeau J, Caron M. Antiretroviral Drugs with Adverse Effects on Adipocyte Lipid Metabolism and Survival Alter the Expression and Secretion of Proinflammatory Cytokines and Adiponectin In Vitro. Antivir Ther 2004. [DOI: 10.1177/135965350400900607] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective The lipodystrophy syndrome is a major adverse effect of highly active antiretroviral therapy (HAART), associated with altered circulating levels and adipose tissue mRNA expression of proinflammatory cytokines interleukin-6 (IL-6) and tumour necrosis factor (TNF)α, and adiponectin. Proinflammatory cytokines and adiponectin, which are secreted by adipose tissue, regulate fat metabolism, insulin sensitivity and adipose cell apoptosis. We examined the direct effects of individual antiretrovirals on lipid metabolism and cytokine and adiponectin production by cultured adipocytes. Methods Differentiating 3T3-F442A cells and differentiated 3T3-L1 adipocytes were treated for 12 or 4 days, respectively, with protease inhibitors (PIs) indinavir, nelfinavir, amprenavir, lopinavir and ritonavir, or nucleoside reverse transcriptase inhibitors (NRTIs) stavudine and zidovudine, at near-Cmax concentrations. Lipid metabolism was estimated by Oil Red O staining of intracellular lipids, mRNA expression of fatty acid synthase and adipocyte lipid binding protein 2, and insulin activation of lipogenesis. Apoptosis was estimated by flow cytometry. The expression and secretion of proinflammatory cytokines (IL-6, TNFα and IL-1β) and adiponectin were evaluated by real-time reverse transcription PCR and ELISA. Results Chronic treatment of 3T3-F442A differentiating adipocytes and differentiated 3T3-L1 adipocytes with PIs and NRTIs reduced lipid accumulation, mRNA expression of lipid markers and insulin-induced lipogenesis. IL-6, TNFα, IL-1β and adiponectin expression and secretion were markedly altered in differentiating 3T3-F442A adipocytes. PIs had either no effect on differentiated 3T3-L1 adipocytes (TNFα expression and secretion) or their effect was less marked than in 3T3-F442A cells. Indinavir and amprenavir did not alter cytokine secretion and expression by mature adipocytes. The effects of stavudine and zidovudine on differentiating and mature adipocytes were similar, despite the difference in treatment procedure. The drugs with the strongest effect on TNFα expression also increased adipocyte apoptosis, in contrast to the drugs that only moderately increased TNFα expression. Conclusions These results suggest that increased cytokine and decreased adiponectin secretion and expression induced by some PIs and NRTIs may contribute to the adipose tissue loss (via apoptosis and lipid leakage) and insulin resistance associated with the lipodystrophy syndrome.
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Affiliation(s)
- Claire Lagathu
- INSERM U402 and IFR65 Saint-Antoine Faculty of Medicine and Biochemistry Department, Tenon Hospital, University Pierre et Marie Curie, Paris, France
| | - Jean-Philippe Bastard
- INSERM U402 and IFR65 Saint-Antoine Faculty of Medicine and Biochemistry Department, Tenon Hospital, University Pierre et Marie Curie, Paris, France
| | - Martine Auclair
- INSERM U402 and IFR65 Saint-Antoine Faculty of Medicine and Biochemistry Department, Tenon Hospital, University Pierre et Marie Curie, Paris, France
| | - Mustapha Maachi
- INSERM U402 and IFR65 Saint-Antoine Faculty of Medicine and Biochemistry Department, Tenon Hospital, University Pierre et Marie Curie, Paris, France
| | - Michel Kornprobst
- INSERM U402 and IFR65 Saint-Antoine Faculty of Medicine and Biochemistry Department, Tenon Hospital, University Pierre et Marie Curie, Paris, France
| | - Jacqueline Capeau
- INSERM U402 and IFR65 Saint-Antoine Faculty of Medicine and Biochemistry Department, Tenon Hospital, University Pierre et Marie Curie, Paris, France
| | - Martine Caron
- INSERM U402 and IFR65 Saint-Antoine Faculty of Medicine and Biochemistry Department, Tenon Hospital, University Pierre et Marie Curie, Paris, France
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71
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Abstract
PURPOSE OF REVIEW Adipose tissue is a dynamic organ that changes mass throughout life in response to the metabolic needs of the animal. In the past three decades, significant advances have been made in delineating key extracellular and intracellular stimulators of fat cell formation or adipogenesis. In this review, the author focuses on new findings of specific inhibitors of adipogenesis. Understanding the balance between positive and negative regulators of adipogenesis has important health-related implications for anti-obesity medical therapy and lipodystrophy. RECENT FINDINGS Adipogenesis is a highly regulated process requiring coordinated expression and activation of two main groups of adipogenic transcription factors, CCAAT/enhancer binding proteins and peroxisome proliferators activated receptor gamma. In response to hormonal and nutrient stimuli, the increased expression and activation of these transcription factors induce the expression of adipocyte-specific genes. More recently, several groups have identified extracellular inhibitors of adipocyte formation, including cytokines, lipid molecules, genistein, and protease inhibitors. Intracellular signaling molecules, which negatively regulate adipogenesis, include Pref-1, Foxo1, Foxa2, SMAD-3, WNT-10b, GATA-2 and GATA-3. SUMMARY The prevalence of obesity is increasing in the United States and in other westernized societies. Understanding the mechanisms of excessive energy storage in adipose tissue is necessary to develop a comprehensive strategy to prevent and treat obesity. One potential, but unrealized, approach to obesity treatment is to target excessive adipose tissue enlargement. A number of promising extra- and intracellular inhibitors of fat cell formation have been identified, but the modulation of adipose tissue mass may have both advantageous and deleterious health effects.
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Affiliation(s)
- Joyce B Harp
- Department of Nutrition and Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
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72
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Wood R, Phanuphak P, Cahn P, Pokrovskiy V, Rozenbaum W, Pantaleo G, Sension M, Murphy R, Mancini M, Kelleher T, Giordano M. Long-Term Efficacy and Safety of Atazanavir With Stavudine and Lamivudine in Patients Previously Treated With Nelfinavir or Atazanavir. J Acquir Immune Defic Syndr 2004; 36:684-92. [PMID: 15167287 DOI: 10.1097/00126334-200406010-00005] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The purpose of the study was to determine long-term efficacy, safety, and tolerability of atazanavir plus stavudine/lamivudine in 346 HIV-infected patients previously treated with atazanavir or nelfinavir. BMS AI424-044 is an ongoing, multicenter, international, open-label, rollover/switch study initiated in June 2001. Patients completing >or=48 weeks in trial BMS AI424-008 with a plasma HIV RNA viral load <10,000 copies/mL were eligible to continue on atazanavir (400 or 600 mg) or to switch from nelfinavir to atazanavir (400 mg) once daily. Antiviral efficacy, change in CD4 cell counts, and effect on lipid parameters were measured. After 24 weeks of atazanavir use in BMS AI424-044, 83%, 85%, and 87% of the atazanavir 400-mg, atazanavir 600-mg, and nelfinavir-to-atazanavir-switched patients, respectively, had HIV RNA levels <400 copies/mL compared with 76%, 76%, and 63%, respectively, at week 48 of BMS AI424-008. Atazanavir-treated patients showed minimal changes in lipid levels compared with baseline. Patients switched from nelfinavir to atazanavir showed significant mean percent decreases in total cholesterol (-16%), fasting low-density lipoprotein cholesterol (-21%), and fasting triglycerides (-28%) (P<0.0001) by week 12 of atazanavir treatment. No new safety issues were identified, and the overall incidence of treatment-emergent adverse events during BMS AI424-044 was comparable across treatment groups. Atazanavir was safe, tolerable, and effective during extended use and in patients switched from nelfinavir. Extended atazanavir use resulted in continued viral suppression and lipid changes that were not clinically relevant. In virologically suppressed nelfinavir-treated patients switched to atazanavir, virologic improvement continued, whereas nelfinavir-induced lipid elevations were reversed within 12 weeks, approaching pretreatment values.
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Affiliation(s)
- Robin Wood
- Somerset Hospital, Capetown, South Africa and Chulalongkorn University, Bangkok, Thailand
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73
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Koutkia P, Grinspoon S. HIV-associated lipodystrophy: pathogenesis, prognosis, treatment, and controversies. Annu Rev Med 2004; 55:303-17. [PMID: 14746523 DOI: 10.1146/annurev.med.55.091902.104412] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Potent antiretroviral agents markedly suppress HIV and have dramatically improved the clinical course, prognosis, and survival of HIV-infected patients. Unfortunately, highly active antiretroviral therapy is often compromised by metabolic complications, including insulin resistance, dyslipidemia, and fat redistribution. Together these changes have been termed the HIV-lipodystrophy syndrome, which is estimated to affect a majority of patients treated with potent combination antiretroviral therapy. Routine testing of fasting glucose is recommended for all HIV-infected patients, particularly those who are obese, have a family history of diabetes mellitus, or are receiving protease inhibitor therapy. Preliminary investigations have demonstrated the potential utility of insulin-sensitizing agents and lipid-lowering therapies to ameliorate these metabolic disturbances. Patients with HIV infection who demonstrate fat redistribution and develop hyperinsulinemia and dyslipidemia may be at increased risk of cardiovascular disease. However, the long-term effects on cardiovascular disease have not yet been determined.
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Affiliation(s)
- Polyxeni Koutkia
- Massachusetts General Hospital Program in Nutritional Metabolism and Neuroendocrine Unit, Harvard Medical School, 55 Fruit Street, Boston, Massachusetts 02114, USA
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74
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Kappert K, Caglayan E, Bäumer AT, Südkamp M, Fätkenheuer G, Rosenkranz S. Ritonavir exhibits anti-atherogenic properties on vascular smooth muscle cells. AIDS 2004; 18:403-11. [PMID: 15090791 DOI: 10.1097/00002030-200402200-00005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES HIV protease inhibitors (PI) such as ritonavir have dramatically decreased HIV-related morbidity and mortality. However they exhibit significant side-effects such as hyperlipidemia, hyperglycemia with or without lipodystrophy, which may increase patients' risk for atherosclerosis. Direct effects of PI on the vascular wall have not been investigated. Platelet-derived growth factor (PDGF) is a major contributor to atherogenesis. DESIGN In the present study the effects of ritonavir on PDGF-BB-induced responses of vascular smooth muscle cells (VSMCs) were evaluated. METHODS PDGF-induced proliferation of VSMCs was measured by BrdU-incorporation, and chemotaxis was assessed by utilizing modified Boyden chambers. Cytotoxicity and apoptosis were quantified using LDH-release- and apoptosis-kits. Immunoprecipitation and Western blot analyses were performed to evaluate betaPDGF receptor (betaPDGFR) expression and phosphorylation, and to monitor intracellular signaling. RESULTS Pretreatment of VSMCs with ritonavir resulted in a significant concentration-dependent inhibition of PDGF-BB-induced cellular responses. At a therapeutic concentration (10 microg/ml), ritonavir significantly reduced PDGF-induced DNA synthesis and chemotaxis by 46.8 +/- 5.5% and 37.2 +/- 3.3%, respectively (P < 0.05 each). In addition it significantly inhibited PDGF-dependent downstream signaling, such as Erk activation. These inhibitory effects were not due to cytotoxicity or apoptosis. Instead, ritonavir inhibited the ligand-induced tyrosine phosphorylation of the betaPDGFR, whereas it did not alter betaPDGFR expression. CONCLUSIONS Ritonavir has direct effects on VSMCs at clinically relevant concentrations in vitro, as it inhibits betaPDGFR activation and PDGF-dependent proliferation and migration of VSMCs. Although ritonavir may increase the risk of vascular disease by its metabolic side effects, it may exhibit anti-atherogenic properties on the cellular level.
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Affiliation(s)
- Kai Kappert
- Klinik III für Innere Medizin, the Abteilung für Herzchirurgie der Universität zu Köln, Joseph-Stelzmann-Str. 9, 50924 Köln, Klinik I für Innere Medizin, Germany
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75
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Gougeon ML, Pénicaud L, Fromenty B, Leclercq P, Viard JP, Capeau J. Adipocytes Targets and Actors in the Pathogenesis of HIV-Associated Lipodystrophy and Metabolic Alterations. Antivir Ther 2004. [DOI: 10.1177/135965350400900206] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The recent clinical use of potent HIV-1 drugs, including nucleoside reverse transcriptase inhibitors (NRTIs) and non-peptidic viral protease inhibitors (PIs), and their combinations, termed highly active antiretroviral therapy (HAART), has dramatically reduced the infection-related mortality of AIDS patients, but it is associated with severe metabolic adverse events such as lipodystrophy syndrome, dyslipidaemia, insulin resistance and diabetes mellitus. The aetiology of this syndrome and metabolic alterations appear to be multifactorial, including HIV drug inhibitory effects on adipocyte differentiation, alteration of mitochondrial functions in adipocytes and altered leptin, adiponectin and cytokine expression in adipose tissue of patients. Adipose tissue may thus be a central regulator in disorganized lipid metabolism and insulin resistance associated with antiretroviral therapy, and we propose in this review to explore how adipose tissue may be a target, but also an actor, in the aetiopathogenesis of the lipodystrophy syndrome.
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Affiliation(s)
- Marie-Lise Gougeon
- Unité d'Immunité Anti-virale, Biothérapie et Vaccins, Département de Medecine Moleculaire, Institut Pasteur, Paris, France
| | - Luc Pénicaud
- Unite Mixte de Recherche 5018, Centre National de la Recherche Scientifique, University Paul Sabatier, Toulouse, France
| | | | - Pascale Leclercq
- Laboratoire de Bioenergetique Fondamentale et Appliquée, Université Joseph Fourier, Grenoble, France
| | - Jean-Paul Viard
- Service des Maladies Infectieuses et Tropicales, Hôpital Necker Enfants-Malades, Paris, France
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76
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Xu A, Yin S, Wong L, Chan KW, Lam KSL. Adiponectin ameliorates dyslipidemia induced by the human immunodeficiency virus protease inhibitor ritonavir in mice. Endocrinology 2004; 145:487-94. [PMID: 14592951 DOI: 10.1210/en.2003-1140] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although the clinical application of HIV protease inhibitors (PIs) has markedly reduced HIV-related morbidity and mortality, it is now recognized that PI-based therapy often causes serious metabolic disorders, including hyperlipidemia and premature atherosclerosis. The etiology of these adverse effects remains obscure. Here, we demonstrate that deficiency of the fat-derived hormone adiponectin might play a role. The steady-state mRNA levels of the adiponectin gene and secretion of this protein from 3T3-L1 adipocytes are significantly decreased after treatment with several PIs (indinavir, nelfinavir, and ritonavir), with ritonavir having the greatest effect. Intragastric administration of ritonavir into mice decreases plasma concentrations of adiponectin and concurrently increases the plasma levels of triglyceride, free fatty acids, and cholesterol. Adiponectin replacement therapy markedly ameliorates ritonavir-induced elevations of triglyceride and free fatty acids. These beneficial effects of adiponectin are partly due to its ability to decrease ritonavir-induced synthesis of fatty acids and triglyceride, and to increase fatty acid combustion in the liver tissue. In contrast, adiponectin has little effect on ritonavir-induced hypercholesterolemia and hepatic cholesterol synthesis. These results suggest that hypoadiponectinemia is partly responsible for the metabolic disorders induced by HIV PIs, and adiponectin or its agonists might be useful for the treatment of these disorders.
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Affiliation(s)
- Aimin Xu
- Department of Medicine, The University of Hong Kong, L8-33A, New Laboratory Block, 21 Sassoon Road, Hong Kong, China.
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77
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Balasubramanyam A, Sekhar RV, Jahoor F, Jones PH, Pownall HJ. Pathophysiology of dyslipidemia and increased cardiovascular risk in HIV lipodystrophy: a model of 'systemic steatosis'. Curr Opin Lipidol 2004; 15:59-67. [PMID: 15166810 DOI: 10.1097/00041433-200402000-00011] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
PURPOSE OF REVIEW This review addresses a syndrome of dyslipidemia and lipodystrophy that has emerged in HIV-infected patients receiving highly active antiretroviral therapy (HAART). The term 'HIV/HAART associated dyslipidemic lipodystrophy (HADL)' describes this syndrome. Although HAART increases patient survival rates, their increased longevity and dyslipidemias place them at risk for cardiovascular disease. Identification of rationally based therapies requires an understanding of the mechanistic basis of HADL. RECENT FINDINGS A case definition for HIV lipodystrophy, based on age, gender, duration of HIV disease, serum HDL cholesterol and anthropometry, provides high diagnostic sensitivity and specificity. The dyslipidemias, mainly hypercholesterolemia, hypertriglyceridemia and low-plasma HDL cholesterol, among HIV-infected patients in the pre- and post-HAART eras are summarized. Clinical studies of HADL patients show increased lipolysis, which increases free fatty acid transfer to liver for incorporation into lipoprotein triglycerides that are secreted, and to skeletal muscle where they impair normal insulin signaling. A model of HADL that includes preferential lipolysis in femoral-gluteal fat depots is presented. Relevant therapies include those that inhibit lipolysis (niacin) or increase hepatic fatty acid oxidation (fibrates). SUMMARY HADL is one of several disorders characterized by dyslipidemia, insulin resistance, and lipodystrophy. The relative acuteness of HADL should facilitate identification of the sequence of metabolic changes that gives rise to the syndrome. Current evidence suggests that deranged energy storage in femoral-gluteal and other peripheral sites is important; the molecular details for the derangement are unknown but are under scrutiny by many investigators.
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78
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El Hadri K, Glorian M, Monsempes C, Dieudonné MN, Pecquery R, Giudicelli Y, Andreani M, Dugail I, Fève B. In vitro suppression of the lipogenic pathway by the nonnucleoside reverse transcriptase inhibitor efavirenz in 3T3 and human preadipocytes or adipocytes. J Biol Chem 2004; 279:15130-41. [PMID: 14722061 DOI: 10.1074/jbc.m312875200] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
A serious metabolic syndrome combining insulin-resistance, dyslipidemia, central adiposity, and peripheral lipoatrophy has arisen in HIV-infected patients receiving highly active antiretroviral therapy. The aim of this work was to examine the effects of the nonnucleoside reverse transcriptase inhibitor (NNRTI) efavirenz on adipocyte differentiation and metabolism. When induced to differentiate in the presence of efavirenz (5-50 microm), 3T3-F442A preadipocytes failed to accumulate cytoplasmic triacylglycerol droplets. This phenomenon was rapidly reversible and was also readily detectable in the 3T3-L1 preadipose cell line and in primary cultures of human preadipocytes. When applied to mature 3T3-F442A adipocytes, efavirenz induced a delayed and moderate reduction in cell triglyceride content. Measurement of [(3)H]deoxyglucose uptake, basal and agonist-stimulated lipolysis, and cell viability indicated that these pathways are not involved in efavirenz effects on triacylglycerol accumulation. By contrast, we found that the NNRTI induced a dramatic dose- and time-dependent decrease in gene and protein expression of the lipogenic transcription factor sterol regulatory element-binding protein-1c (SREBP-1c). Adipose conversion was only altered at the highest efavirenz concentrations, as suggested by the mild reduction in peroxisome proliferator-activated receptor-gamma and CCAAT/enhancer-binding protein-alpha. CCAAT/enhancer-binding protein-beta remained unchanged. The inhibition of SREBP-1c expression was accompanied by a sharp reduction in the expression of SREBP-1c target genes and in the adipocyte lipogenic activity in efavirenz-treated cells. Finally, the inhibitory effect of efavirenz on cell triglyceride accumulation was prevented by directly providing free fatty acids to the cells and was reversed by overexpression of a dominant positive form of SREBP-1c, reinforcing the implication of this transcription factor in the antilipogenic effect of the drug. When considered together, these results demonstrate for the first time that the NNRTI efavirenz induces a strong inhibition of the SREBP-1c-dependent lipogenic pathway that might contribute to adipose tissue atrophy.
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Affiliation(s)
- Khadija El Hadri
- UMR CNRS 7079-Université Paris VI and INSERM U465, Centre de Recherches Biomédicales des Cordeliers, 15 rue de l'Ecole de Médecine, 75006 Paris, France
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79
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Goetzman ES, Tian L, Nagy TR, Gower BA, Schoeb TR, Elgavish A, Acosta EP, Saag MS, Wood PA. HIV protease inhibitor ritonavir induces lipoatrophy in male mice. AIDS Res Hum Retroviruses 2003; 19:1141-50. [PMID: 14709251 DOI: 10.1089/088922203771881248] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We investigated the effects of the HIV protease inhibitor ritonavir on body composition, serum lipids, and gene expression in C57BL/6 mice. Dual-energy X-ray absorptiometry measurements in ritonavir-treated male mice revealed whole-body lipoatrophy. In female mice fat reduction was restricted to the gonadal depot. A histopathological analysis showed no visible abnormalities in liver or adipose tissue from ritonavir-treated mice, although adipocytes were significantly smaller in diameter. Serum triglyceride levels were increased in ritonavir-treated male mice. Ritonavir was coadministered with the peroxisome proliferator-activated receptor alpha (PPARalpha) agonist gemfibrozil and the PPARgamma agonist rosiglitazone for 8 weeks. Neither drug alleviated the hypertriglyceridemia or lipoatrophy in ritonavir-treated male mice. Rather, gemfibrozil exacerbated the lipoatrophy. Ritonavir reduced basal expression of two PPARalpha target genes in liver, as well as the PPARgamma target gene phosphoenolpyruvate carboxykinase (PEPCK) in adipose tissues. Ritonavir partially inhibited induction of PPAR target genes by gemfibrozil and rosiglitazone. Gemfibrozil induced expression of fatty acid oxidation genes in liver, and this induction was less substantial when ritonavir was coadministered. Similarly, rosiglitazone induced expression of uncoupling protein-1, uncoupling protein-2, and PEPCK in adipose tissues, and this effect was partially inhibited by ritonavir. Thus, the effects of ritonavir on serum triglycerides and body composition may be due, at least in part, to an inhibition of PPAR function.
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Affiliation(s)
- Eric S Goetzman
- Department of Genetics, University of Alabama at Birmingham, Alabama 35294, USA
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80
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Caron M, Auclair M, Sterlingot H, Kornprobst M, Capeau J. Some HIV protease inhibitors alter lamin A/C maturation and stability, SREBP-1 nuclear localization and adipocyte differentiation. AIDS 2003; 17:2437-44. [PMID: 14600514 DOI: 10.1097/00002030-200311210-00005] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To study whether HIV protease inhibitors could induce nuclear lamina alterations in adipocytes as observed in a genetic form of lipodystrophy due to lamin A/C mutation. DESIGN We have previously observed that indinavir (IDV) impairs adipocyte differentiation and sterol regulatory element-binding protein-1 (SREBP-1) nuclear localization in 3T3-F442A adipocytes. We compared here the effects of IDV with that produced by two other PIs, nelfinavir (NFV) and amprenavir (APV) on adipose conversion, cellular localization of SREBP-1, nuclear morphology, and maturation and stability of the lamina network. RESULTS IDV and NFV, but not APV, altered adipose cell differentiation, as shown by lipid staining and protein expression of SREBP-1, CAAAT/enhancer binding protein (C/EBP)alpha and fatty acid synthase (FAS). In IDV-treated cells, 50-60 % of the nuclei could not accumulate SREBP-1. Twenty percent of these SREBP-negative nuclei were grossly dysmorphic, with blebs and prominent herniations, and showed an altered distribution of lamin A/C and lamin B. In IDV-treated cells, nuclear fragilization was shown by the abnormal extractibility of lamina proteins and SREBP-1, and the accumulation of prelamin A. NFV similarly altered lamin A/C maturation whereas APV was almost ineffective. CONCLUSIONS We show in an adipose cell line that IDV and NFV induced alterations at the nuclear level by promoting defects in lamin A/C maturation, organization and stability. We suggest that these lamina network alterations might be responsible for SREBP-1 nuclear mislocalization therefore resulting in altered adipocyte differentiation.
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Affiliation(s)
- Martine Caron
- INSERM U. 402, Faculté de Médecine Saint-Antoine, Paris, France
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81
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Abstract
In HIV patients, chronic treatment with protease inhibitors often precipitates a peripheral lipodystrophy associated with insulin resistance syndrome and premature coronary disease. In vitro studies demonstrate that these drugs can compromise the ability of adipocytes to store triglycerides; in vivo, peripheral subcutaneous adipocytes appear to be most affected, such that body fat often redistributes to visceral or truncal adipose stores. Dysfunction of peripheral subcutaneous adipocytes - ordinarily quite efficient for storing fat - can be expected to give rise to an excessive flux of free fatty acids (FFAs) following fatty meals; chronic overexposure of tissues to FFAs is a likely explanation for the insulin resistance syndrome associated with lipodystrophy. These considerations suggest that a very-low-fat diet - less than 15% fat calories - may ameliorate the cardiovascular risk associated with lipodystrophy; such diets are known to have a favorable effect on the insulin sensitivity of healthy subjects. Very-low-fat whole-food vegan diets are particularly recommendable in this context, as they may help to shrink visceral fat depots while markedly reducing LDL cholesterol. Appropriate adjunctive measures may include aerobic exercise training - beneficial both for insulin sensitivity and weight control - as well as administration of statins or policosanol, and of fibrates or fish oil, to decrease LDL and triglycerides, respectively. Despite perceptions to the contrary, very-low-fat diets can meet with good compliance in well-motivated subjects given appropriate instruction.
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Affiliation(s)
- M F McCarty
- Pantox Laboratories, San Diego, CA 92109, USA.
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82
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Yarasheski KE, Tebas P, Claxton S, Marin D, Coleman T, Powderly WG, Semenkovich CF. Visceral adiposity, C-peptide levels, and low lipase activities predict HIV-dyslipidemia. Am J Physiol Endocrinol Metab 2003; 285:E899-905. [PMID: 12837664 DOI: 10.1152/ajpendo.00036.2003] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Protease inhibitor-based highly active antiretroviral therapy (PI-HAART) has been implicated in dyslipidemia, peripheral insulin resistance, and abnormal adipose tissue deposition in human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome, or AIDS. In vitro evidence indicates that some PIs reduce adipocyte lipoprotein (LPL) and hepatic lipase (HL) expression and activities. We examined whether LPL and HL activities are reduced in HIV-infected patients with dyslipidemia. Fasting serum lipids, glucoregulatory hormones, and postheparin LPL and HL activities, as well as whole body and regional adiposity, were measured in 19 HIV-seronegative controls, 9 HIV+ patients naive to all anti-HIV medications, 9 HIV+ patients naive to PIs, 9 HIV+ patients with prior PI experience but not currently receiving PIs, and 47 HIV+ patients receiving PI-HAART. The PI-HAART group had low LPL and HL activities. However, multiple linear regression analysis indicated that low postheparin LPL activity contributed only partially to HIV-dyslipidemia. Central adiposity and high C-peptide levels (an indicator of high insulin secretion) were stronger predictors of HIV-dyslipidemia. Low LPL and HL activities, by themselves, were insufficient to explain HIV-dyslipidemia because the PI-naive group had low LPL and HL activities but had normal adiposity, C-peptide levels, and serum lipid and lipoprotein levels. HDL-cholesterol was lower in PI-HAART and PI-naive groups than seronegative controls and was directly associated with LPL activity. These findings suggest that HIV-dyslipidemia is mediated primarily by factors that influence triglyceride and lipoprotein synthesis (e.g., central adiposity and hyperinsulinemia) and mediated only partially by factors that influence triglyceride clearance (e.g., lipase activity).
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Affiliation(s)
- Kevin E Yarasheski
- Division of Endocrinology, Metabolism and Lipid Research, Washington University Medical School, 660 South Euclid Avenue, Box 8127, St. Louis, MO 63110, USA.
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83
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Kannisto K, Sutinen J, Korsheninnikova E, Fisher RM, Ehrenborg E, Gertow K, Virkamäki A, Nyman T, Vidal H, Hamsten A, Yki-Järvinen H. Expression of adipogenic transcription factors, peroxisome proliferator-activated receptor gamma co-activator 1, IL-6 and CD45 in subcutaneous adipose tissue in lipodystrophy associated with highly active antiretroviral therapy. AIDS 2003; 17:1753-62. [PMID: 12891061 DOI: 10.1097/00002030-200308150-00004] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To determine the expressions of multiple genes in the subcutaneous adipose tissue of HIV-positive, highly active antiretroviral therapy (HAART)-treated patients with and without lipodystrophy. DESIGN AND METHODS Real-time polymerase chain reaction was used to measure gene expressions in this cross-sectional study. RESULTS The messenger RNA concentrations of adipose transcription factors (peroxisome proliferator-activated receptor (PPAR) gamma and delta and sterol regulatory element binding protein 1c) were all significantly lower in the lipodystrophic than the non-lipodystrophic group. The mRNA concentration of PPAR-gamma co-activator 1 (PGC-1), which regulates mitochondrial biogenesis, was lower in the lipodystrophic than the non-lipodystrophic group. The mRNA expression of lipoprotein lipase, acyl coenzyme A synthase and glucose transport protein 4 were significantly lower in the lipodystrophic than the non-lipodystrophic group, but the mRNA concentrations of fatty acid transport and binding proteins were similar in both groups. The mRNA concentrations of IL-6 and CD45 (a common leukocyte marker) were significantly higher in the lipodystrophic than the non-lipodystrophic group. CONCLUSION Multiple alterations characterize gene expression in the subcutaneous adipose tissue of patients with HAART-associated lipodystrophy compared with HIV-positive, HAART-treated patients without lipodystrophy. The low expression of transcription factors inhibits adipocyte differentiation. The low expression of PGC-1 may contribute to mitochondrial defects. In addition, IL-6 and CD45 expressions are increased, the latter implying an excessive number of cells of leukocyte origin in lipodystrophic adipose tissue. Mitochondrial injury and an excess of proinflammatory cytokines may lead to increased apoptosis. All these changes may contribute to the loss of subcutaneous fat in HAART-associated lipodystrophy.
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Affiliation(s)
- Katja Kannisto
- Department of Medicine, Atherosclerosis Research Unit, King Gustaf V Research Institute, Karolinska Institutet, Stockholm, Sweden
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84
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Nadler JP, Gathe JC, Pollard RB, Richmond GJ, Liao Q, Griffith S, Tracey Lancaster C, Hernandez JE, Pappa KA. Twice-daily amprenavir 1200 mg versus amprenavir 600 mg/ritonavir 100 mg, in combination with at least 2 other antiretroviral drugs, in HIV-1-infected patients. BMC Infect Dis 2003; 3:10. [PMID: 12795812 PMCID: PMC165437 DOI: 10.1186/1471-2334-3-10] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2003] [Accepted: 06/10/2003] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Low-dose ritonavir (RTV) boosts plasma amprenavir (APV) exposure. Little has been published on the efficacy, tolerability, and safety of APV 600 mg/RTV 100 mg (APV600/RTV) twice daily (BID) compared to APV 1200 mg BID (APV1200). METHODS ESS40011 was a 24-week, multicenter, open-label, clinical trial in which antiretroviral therapy-naïve and -experienced HIV-1-infected adults were randomized 3:1 to receive either APV600/RTV BID or APV1200 BID, in combination with > or = 2 non-protease inhibitor antiretroviral drugs. Non-inferiority of the APV600/RTV regimen to the APV1200 regimen was established if the 95% lower confidence limit for the difference in proportion of patients achieving HIV-1 RNA <200 copies/mL at week 24 with APV 600/RTV minus APV1200 was > or =-0.12. Late in the conduct of the trial, patients not yet completing 24 weeks of therapy were given the option of continuing treatment for an additional 24-week period. RESULTS 211 patients were randomized, 158 to APV600/RTV and 53 to APV1200. At week 24, APV600/RTV was similar to or better than APV1200 (HIV-1 RNA <200 copies/mL in 62% [73/118] vs 53% [20/38] of patients; intent-to-treat: observed analysis). In the APV600/RTV arm, significantly more patients achieved HIV-1 RNA <50 copies/mL (48% [57/118] vs 29% [11/38] with APV1200, P = 0.04), and greater mean reduction from baseline in HIV-1 RNA was observed (-2.21 vs -1.59 log10 copies/mL, P = 0.028). The two treatment arms were similar with respect to mean overall change from baseline in CD4+ count, frequency of drug-related grade 1-4 adverse events, and frequency of discontinuing treatment due to adverse events (most commonly nausea, diarrhea, vomiting or fatigue; 7% vs 8%), although a lower proportion of patients in the APV600/RTV arm experienced drug-related oral/perioral paresthesia (2% vs 8%). Eleven (73%) of 15 patients who had HIV-1 RNA <200 copies/mL at week 24 and chose to continue study treatment maintained this level of virologic suppression at follow-up 24 weeks later. CONCLUSIONS APV600 RTV BID was similar to or better than APV1200 BID in virologic response. Virologic results in a small number of patients who continued treatment for 24 weeks post-study suggest that virologic suppression with APV600 RTV BID is durable.
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Affiliation(s)
- Jeffrey P Nadler
- University of South Florida, College of Medicine, Tampa, Florida, USA
| | | | | | - Gary J Richmond
- Broward General Medical Center, Fort Lauderdale, Florida, USA
| | - Qiming Liao
- GlaxoSmithKline, Research Triangle Park, North Carolina, USA
| | - Sandy Griffith
- GlaxoSmithKline, Research Triangle Park, North Carolina, USA
| | | | | | - Keith A Pappa
- GlaxoSmithKline, Research Triangle Park, North Carolina, USA
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85
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Woerle HJ, Mariuz PR, Meyer C, Reichman RC, Popa EM, Dostou JM, Welle SL, Gerich JE. Mechanisms for the deterioration in glucose tolerance associated with HIV protease inhibitor regimens. Diabetes 2003; 52:918-25. [PMID: 12663461 DOI: 10.2337/diabetes.52.4.918] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The mechanisms responsible for the deterioration in glucose tolerance associated with protease inhibitor-containing regimens in HIV infection are unclear. Insulin resistance has been implicated as a major factor, but the affected tissues have not been identified. Furthermore, beta-cell function has not been evaluated in detail. The present study was therefore undertaken to assess the effects of protease inhibitor-containing regimens on hepatic, muscle, and adipose tissue insulin sensitivity as well as pancreatic beta-cell function. We evaluated beta-cell function in addition to glucose production, glucose disposal, and free fatty acid (FFA) turnover using the hyperglycemic clamp technique in combination with isotopic measurements in 13 HIV-infected patients before and after 12 weeks of treatment and in 14 normal healthy volunteers. beta-Cell function and insulin sensitivity were also assessed by homeostasis model assessment (HOMA). Treatment increased fasting plasma glucose concentrations in all subjects (P < 0.001). Insulin sensitivity as assessed by HOMA and clamp experiments decreased by approximately 50% (P < 0.003). Postabsorptive glucose production was appropriately suppressed for the prevailing hyperinsulinemia, whereas glucose clearance was reduced (P < 0.001). beta-Cell function decreased by approximately 50% (P = 0.002), as assessed by HOMA, and first-phase insulin release decreased by approximately 25%, as assessed by clamp data (P = 0.002). Plasma FFA turnover and clearance both increased significantly (P < 0.001). No differences at baseline or in responses after treatment were observed between drug naïve patients who were started on a nucleoside reverse transcriptase inhibitor (NRTI) plus a protease inhibitor and patients who had been on long-term NRTI treatment and had a protease inhibitor added. The present study indicates that protease inhibitor-containing regimens impair glucose tolerance in HIV-infected patients by two mechanisms: 1) inducement of peripheral insulin resistance in skeletal muscle and adipose tissue and 2) impairment of the ability of the beta-cell to compensate.
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Affiliation(s)
- Hans J Woerle
- Department of Medicine, University of Rochester School of Medicine, Rochester, New York, USA
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86
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87
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Ben-Romano R, Rudich A, Török D, Vanounou S, Riesenberg K, Schlaeffer F, Klip A, Bashan N. Agent and cell-type specificity in the induction of insulin resistance by HIV protease inhibitors. AIDS 2003; 17:23-32. [PMID: 12478066 DOI: 10.1097/00002030-200301030-00005] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To test agent and cell-type specificity in insulin resistance induced by prolonged exposure to HIV protease inhibitors (HPI), and to assess its relation to the direct, short-term inhibition of insulin-stimulated glucose uptake. METHODS Following prolonged (18 h) and short (5-10 min) exposure to HPI, insulin-stimulated glucose transport, protein kinase B (PKB) phosphorylation, and GLUT4 translocation were evaluated in 3T3-L1 adipocytes, fibroblasts, L6 myotubes, and L6 cells overexpressing a myc tag on the first exofacial loop of GLUT4 or GLUT1. RESULTS Prolonged exposure of 3T3-L1 adipocytes to nelfinavir, but not to indinavir or saquinavir, resulted in increased basal lipolysis but decreased insulin-stimulated glucose transport and PKB phosphorylation. In addition, impaired insulin-stimulated glucose uptake and PKB phosphorylation were also observed in the skeletal muscle cell line L6, and in 3T3-L1 fibroblasts. Interestingly, this coincided with increased basal glucose uptake as well as with elevated total-membrane glucose transporter GLUT1 protein content. In contrast to these unique effects of nelfinavir, the mere presence of any of the agents in the 5 min transport assay inhibited insulin-stimulated glucose-uptake activity. This appeared to be caused by direct and specific interaction of the drugs with GLUT4 fully assembled at the plasma membrane, since insulin-stimulated cell-surface exposure of an exofacial myc epitope on GLUT4 was normal. CONCLUSIONS Independent mechanisms for HPI-induced insulin resistance exist: prolonged exposure to nelfinavir interferes with insulin signaling and alters cellular metabolism of adipocytes and muscle cells, whereas a direct inhibitory effect on insulin-stimulated glucose uptake may occurs through specific interaction of HPI with GLUT4.
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Affiliation(s)
- Ronit Ben-Romano
- Department of Clinical Biochemistry, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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88
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Cammalleri C, Germinario RJ. The effects of protease inhibitors on basal and insulin-stimulated lipid metabolism, insulin binding, and signaling. J Lipid Res 2003; 44:103-8. [PMID: 12518028 DOI: 10.1194/jlr.m200245-jlr200] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The objective of our research was to investigate the effects of the protease inhibitors ritonavir, saquinavir, and indinavir on triglyceride synthesis, lipolysis, insulin binding, and signaling in differentiating 3T3 L1 pre-adipocytes. Saquinavir, ritonavir, and indinavir all stimulated triglyceride (TG) synthesis. Additionally, all concentrations of protease inhibitors employed (i.e., 0.1 micro M to 10 micro M) significantly decreased insulin-stimulated TG synthesis. No effects of any of the protease inhibitors were observed either on basal lipolysis or after stimulation of lipolysis with 100 nM noradrenaline. Specific (125)I-insulin binding was observed to be decreased by exposure to all the protease inhibitors throughout the period of adipocyte phenotype development. This was mediated by indinavir through a receptor decrease and had no effect on receptor affinity. During differentiation with ritonavir (i.e., 1-11 days post addition of differentiating cocktail), insulin receptor substrate-1 (IRS-1) tyrosine phosphorylation was ascertained (day 11) and found to be decreased in the ritonavir exposed cells when compared with control cells. The results reported herein demonstrate protease inhibitor effects on basal TG synthesis while exhibiting decreased insulin-stimulated TG synthesis at physiological concentrations of protease inhibitors. These effects may be subsequent to decreased insulin binding and/or IRS-1 tyrosine phosphorylation.
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89
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Behrens GM, Boerner AR, Weber K, van den Hoff J, Ockenga J, Brabant G, Schmidt RE. Impaired glucose phosphorylation and transport in skeletal muscle cause insulin resistance in HIV-1–infected patients with lipodystrophy. J Clin Invest 2002. [DOI: 10.1172/jci200215626] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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90
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Behrens GMN, Boerner AR, Weber K, van den Hoff J, Ockenga J, Brabant G, Schmidt RE. Impaired glucose phosphorylation and transport in skeletal muscle cause insulin resistance in HIV-1-infected patients with lipodystrophy. J Clin Invest 2002; 110:1319-27. [PMID: 12417571 PMCID: PMC151608 DOI: 10.1172/jci15626] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Insulin resistance is a frequently observed side effect of highly active antiretroviral therapy (HAART). Currently, very little is known about the mechanisms or specific tissues involved. We aimed to identify possible defects in skeletal muscle glucose uptake and metabolism in HIV patients receiving HAART. Whole-body glucose disposal and oxidation were determined by combination of the euglycemic-hyperinsulinemic clamp technique and indirect calorimetry. Muscle glucose uptake of the thighs was measured simultaneously by dynamic 2[(18)F]fluoro-2-deoxy-D-glucose positron emission tomography. Patients receiving HAART had signs of lipodystrophy as confirmed by dual energy x-ray absorptiometry. Whole-body glucose disposal was significantly reduced in these patients compared with untreated patients. Analysis of kinetic constants using a three-compartment model indicated reduced skeletal glucose uptake caused by significantly impaired glucose transport and phosphorylation. Skeletal muscle glucose uptake was reduced by 66% in treated patients and explained 46% and 43% of whole-body glucose disposal in patients on HAART and therapy-naive patients, respectively. Insulin-stimulated whole-body oxidative and nonoxidative glucose disposal was significantly lower in the treated group, as was suppressive insulin action on lipolysis. To our knowledge, this is the first report providing in vivo evidence that, in lipodystrophic HIV patients, impaired glucose transport and phosphorylation cause reduced insulin-mediated glucose uptake.
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Affiliation(s)
- Georg M N Behrens
- Department of Clinical Immunology, Hannover Medical School, Hannover, Germany.
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91
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Maher B, Alfirevic A, Vilar FJ, Wilkins EGL, Park BK, Pirmohamed M. TNF-alpha promoter region gene polymorphisms in HIV-positive patients with lipodystrophy. AIDS 2002; 16:2013-8. [PMID: 12370499 DOI: 10.1097/00002030-200210180-00005] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE The pathogenic mechanisms underlying lipodystrophy in HIV-positive patients are largely unknown. TNF-alpha has many actions that are consistent with the features of lipodystrophy; therefore, an analysis was carried out to determine whether functionally active polymorphisms in the promoter region of the TNF-alpha gene are associated with the development of lipodystrophy. DESIGN Genetic case-control association study. METHODS Individuals were genotyped for the -238 and -308 polymorphisms in the TNF-alpha gene using polymerase chain reaction-restriction fragment length polymorphism analysis. The genotype and allele frequencies for 61 HIV-positive patients with lipodystrophy were compared with (a) 35 HIV-positive patients with no evidence of lipodystrophy and (b) 239 healthy HIV-negative individuals. RESULTS The frequency of the variant rare -238 allele was significantly different (P = 0.01) in HIV-positive patients with lipodystrophy than in those without lipodystrophy. At the genotype level, a trend towards a difference between patients with and without lipodystrophy was observed (chi2 for linear trend 5.2, P = 0.02). For the -308 polymorphism, no difference was found in genotype and allele frequencies between HIV patients with and without lipodystrophy. CONCLUSIONS The data suggest that the -238 (but not the -308) promoter region TNF-alpha gene polymorphism is a determinant in the development of HIV-related lipodystrophy. However, the results need to be confirmed in larger numbers of patients as well as in an ethnically diverse population.
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Affiliation(s)
- Bridget Maher
- Department of Pharmacology, The University of Liverpool, Ashton Street, Liverpool, UK
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92
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Abstract
HIV infection is associated with a number of adverse consequences, including metabolic disorders. This article reviews disorders such as wasting, lipid metabolism disorders (including fat redistribution or dyslipidemia), glucose abnormalities, bone disease, and endocrine disorders such as hypogonadism in the presence of HIV infection and/or drug abuse. The issues covered are current estimations of prevalence, risk factors, underlying pathophysiology, diagnosis, and interventions (prevention and treatment) for metabolic complications of HIV and drug abuse.
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Affiliation(s)
- Adrian Dobs
- The John Hopkins University School of Medicine, Baltimore, Maryland, USA.
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93
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Skolnik PR, Rabbi MF, Mathys JM, Greenberg AS. Stimulation of peroxisome proliferator-activated receptors alpha and gamma blocks HIV-1 replication and TNFalpha production in acutely infected primary blood cells, chronically infected U1 cells, and alveolar macrophages from HIV-infected subjects. J Acquir Immune Defic Syndr 2002; 31:1-10. [PMID: 12352144 DOI: 10.1097/00126334-200209010-00001] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Metabolic disorders in HIV-infected patients, especially those receiving highly active antiretroviral therapy (HAART) regimens containing protease inhibitors, are associated with insulin resistance. These metabolic disorders include fat redistribution, diabetes, and hypertriglyceridemia. Thiazolidinediones (TZDs) are used to treat patients with diabetes secondary to insulin resistance, and TZDs are being studied in HAART-related metabolic disorders. We studied the effects of TZDs (peroxisome proliferator-activated receptor-gamma [PPARgamma] agonists) and a PPARalpha agonist on HIV replication and TNFalpha production in peripheral blood mononuclear cells (PBMCs) acutely infected with HIV-1, in a chronically infected monoblastoid cell line (U1) and in alveolar macrophages (AMs) from HIV-infected subjects and uninfected controls. Rosiglitazone, ciglitazone, troglitazone, and PgJ (PPARgamma agonists) as well as fenofibrate (PPARalpha agonist) inhibited HIV replication in both PBMCs and U1 cells. These agents also inhibited TNFalpha production, but the magnitude of TNFalpha inhibition was not directly correlated with the quantitative decreases in HIV replication. In AMs, ciglitazone, rosiglitazone, and troglitazone reduced TNFalpha production. We hypothesize that alterations in mitogen-activated protein kinase signaling pathways have contemporaneous and interrelated effects on HIV replication, cytokine production, and lipid metabolism. Modulation of these pathways using PPAR agonists may improve the metabolic alterations during HAART in conjunction with desirable decreases in HIV replication and TNFalpha production.
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Affiliation(s)
- Paul R Skolnik
- Center for HIV/AIDS Care and Research, Boston University Medical Center, Evans Medical Foundation, Massachusetts 02118, USA.
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94
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Dubé MP, Qian D, Edmondson-Melançon H, Sattler FR, Goodwin D, Martinez C, Williams V, Johnson D, Buchanan TA. Prospective, intensive study of metabolic changes associated with 48 weeks of amprenavir-based antiretroviral therapy. Clin Infect Dis 2002; 35:475-81. [PMID: 12145733 DOI: 10.1086/341489] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2001] [Revised: 03/04/2002] [Indexed: 12/16/2022] Open
Abstract
To determine whether a 48-week course of amprenavir-based antiretroviral therapy is associated with metabolic alterations, 14 clinically stable human immunodeficiency virus (HIV)-infected, protease inhibitor-naive adults initiated amprenavir-based triple therapy. Twelve subjects (86%) achieved HIV RNA levels of <400 copies/mL at week 24. Fasting glucose and insulin levels did not change. Insulin sensitivity did not decrease in the first 24 weeks, but a trend toward a decrease appeared at week 48. Six subjects experienced onset or worsening of glucose tolerance by week 24. Levels of fasting triglycerides and low-density lipoprotein, high-density lipoprotein, and total cholesterol increased. Bone mineral content, lean tissue, total fat, trunk fat, limb fat, and the ratio of trunk to limb fat increased at week 48. Amprenavir-based therapy was associated with increases in serum lipid levels but no short-term decrease in insulin sensitivity. A trend toward insulin resistance appeared late in the study following weight gain, particularly of trunk fat, but without loss of limb fat.
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Affiliation(s)
- Michael P Dubé
- Department of Medicine, Division of Infectious Diseases, Indiana University School of Medicine, Indianapolis, IN, USA.
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95
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Janneh O, Hoggard PG, Tjia JF, Jones SP, Khoo SH, Maher B, Back DJ, Pirmohamed M. Intracellular Disposition and Metabolic Effects of Zidovudine, Stavudine and Four Protease Inhibitors in Cultured Adipocytes. Antivir Ther 2002. [DOI: 10.1177/135965350300800509] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objective The pathogenesis of lipodystrophy caused by the HIV protease inhibitors (PIs) and nucleoside reverse transcriptase inhibitors (NRTIs) is unclear. We have investigated the disposition of these drugs in adipocytes and the consequent effect on adipocyte metabolism and viability. Design Laboratory study utilizing two murine cell lines, 3T3-L1 and 3T3-F442A. Methods Intracellular NRTI phosphate and PI concentrations were determined by HPLC and HPLC-MS/MS, respectively. The cytotoxicity of the drugs was examined on the different adipogenic stages together with their effects on glucose uptake plus or minus insulin, and on glycerol and triglyceride levels. Results There was rapid intracellular accumulation and phosphorylation of [3H]-zidovudine and -stavudine to their phosphate metabolites in adipocytes. The NRTIs were not cytotoxic, did not affect preadipocyte protein synthesis and did not inhibit adipogenesis or induce lipolysis. PIs accumulated in adipocytes (nelfinavir>saquinavir>ritonavir>indinavir). All PIs, except indinavir, were cytotoxic and inhibited adipogenesis, increased lipolysis and impaired preadipocyte protein synthesis. PIs inhibited glucose uptake in the rank order: indinavir>saquinavir>ritonavir>nelfinavir. Conclusion These data demonstrate that PIs may play a role in the insulin resistance observed in lipodystrophy by affecting glucose uptake, adipogenesis and lipolysis. NRTIs alone do not seem to have any effect on adipocyte metabolism despite undergoing phosphorylation to their triphosphorylated anabolites, although their effects in combination with PIs in perturbing adipocyte metabolism warrants further investigation.
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Affiliation(s)
- Omar Janneh
- Department of Pharmacology and Therapeutics, The University of Liverpool, Liverpool, UK
| | - Patrick G Hoggard
- Department of Pharmacology and Therapeutics, The University of Liverpool, Liverpool, UK
| | - John F Tjia
- Department of Pharmacology and Therapeutics, The University of Liverpool, Liverpool, UK
| | - Simon P Jones
- Department of Pharmacology and Therapeutics, The University of Liverpool, Liverpool, UK
| | - Saye H Khoo
- Department of Pharmacology and Therapeutics, The University of Liverpool, Liverpool, UK
| | - Bridget Maher
- Department of Pharmacology and Therapeutics, The University of Liverpool, Liverpool, UK
| | - David J Back
- Department of Pharmacology and Therapeutics, The University of Liverpool, Liverpool, UK
| | - Munir Pirmohamed
- Department of Pharmacology and Therapeutics, The University of Liverpool, Liverpool, UK
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Jain RG, Lenhard JM. Select HIV protease inhibitors alter bone and fat metabolism ex vivo. J Biol Chem 2002; 277:19247-50. [PMID: 11937496 DOI: 10.1074/jbc.c200069200] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Human immunodeficiency virus (HIV) therapies have been associated with alterations in fat metabolism and bone mineral density. This study examined the effects of HIV protease inhibitors (PIs) on bone resorption, bone formation, and adipocyte differentiation using ex vivo cultured osteoclasts, osteoblasts, and adipocytes, respectively. Osteoclast activity, measured using a rat neonatal calvaria assay, increased in the presence of nelfinavir (NFV; 47.2%, p = 0.001), indinavir (34.6%, p = 0.001), saquinavir (24.3%, p = 0.001), or ritonavir (18%, p < 0.01). In contrast, lopinavir (LPV) and amprenavir did not increase osteoclast activity. In human mesenchymal stem cells (hMSCs), the PIs LPV and NFV decreased osteoblast alkaline phosphatase enzyme activity and gene expression significantly (p < 0.05). LPV and NFV diminished calcium deposition and osteoprotegrin expression (p < 0.05), whereas the other PIs investigated did not. Adipogenesis of hMSCs was strongly inhibited by saquinavir and NFV (>50%, p < 0.001) and moderately inhibited by ritonavir and LPV (>40%, p < 0.01). Expression of diacylglycerol transferase, a marker of adipocyte differentiation, decreased in hMSCs treated with NFV. Amprenavir and indinavir did not affect adipogenesis or lipolysis. These results suggest that bone and fat formation in hMSCs of bone marrow may be coordinately down-regulated by some but not all PIs.
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Affiliation(s)
- Renu G Jain
- Department of Metabolic Diseases, GlaxoSmithKline Inc., Research Triangle Park, North Carolina 27709, USA
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97
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Sutinen J, Häkkinen AM, Westerbacka J, Seppälä-Lindroos A, Vehkavaara S, Halavaara J, Järvinen A, Ristola M, Yki-Järvinen H. Rosiglitazone in the Treatment of Haart-Associated Lipodystrophy – a Randomized Double-Blind Placebo-Controlled Study. Antivir Ther 2002. [DOI: 10.1177/135965350300800303] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Highly active antiretroviral therapy (HAART) is associated with metabolic adverse events such as insulin resistance and lipodystrophy, that is, atrophy of subcutaneous fat and accumulation of intra-abdominal fat. Currently, there is no pharmacological treatment for lipoatrophy. Glitazones, a novel class of insulin-sensitizing anti-diabetic agents, increase subcutaneous fat in patients with type 2 diabetes. There are no controlled studies of glitazones in patients with HAART-associated lipodystrophy (HAL). In this randomized, double-blind, placebo-controlled study, 30 patients with HAL received either rosiglitazone (8 mg daily) or placebo for 24 weeks. Baseline characteristics were compared to a group of 30 age-, sex- and weight-matched HIV-negative controls. At baseline, patients with HAL had 1.8-fold (P<0.001) more intra-abdominal and 2.4-fold (P<0.05) more liver fat than HIV-negative controls, who had 1.8-fold (P<0.001) more subcutaneous fat than the patients. After 24 weeks of treatment, rosiglitazone had no effect on body weight, subcutaneous or intra-abdominal fat (magnetic resonance imaging), total body fat (bioimpedance analysis), anthropometric measurements or serum leptin concentrations (a circulating marker of adipose tissue mass). However, rosiglitazone decreased % liver fat (spectroscopy) and serum insulin concentrations, and normalized liver function tests. During the first 12 weeks of rosiglitazone treatment, serum triglycerides increased from 3.5 ±0.5 to 6.5 ±2.0 mmol/l (from 310 ±44 to 575 ±177 mg/dl) (P<0.05) and serum cholestrol from 6.0 ±0.4 to 7.8 ±0.7 mmol/l (from 232 ±15 to 301 ±27 mg/dl) (P<0.01). Contrary to data in other patient groups, rosiglitazone did not increase subcutaneous fat in patients with HAL after 24 weeks of treatment. Rosiglitazone seemed to ameliorate insulin resistance judged by the decreased serum insulin concentrations and % liver fat. Rosiglitazone unexpectedly caused significant increases in serum triglyceride and cholesterol concentrations, which must be carefully monitored if glitazones are used in these patients.
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Affiliation(s)
- Jussi Sutinen
- Department of Medicine, Divisions of Diabetes, Helsinki University Central Hospital, Helsinki, Finland
| | - Anna-Maija Häkkinen
- Departments of Oncology, Helsinki University Central Hospital, Helsinki, Finland
| | - Jukka Westerbacka
- Department of Medicine, Divisions of Diabetes, Helsinki University Central Hospital, Helsinki, Finland
| | - Anneli Seppälä-Lindroos
- Department of Medicine, Divisions of Diabetes, Helsinki University Central Hospital, Helsinki, Finland
| | - Satu Vehkavaara
- Department of Medicine, Divisions of Diabetes, Helsinki University Central Hospital, Helsinki, Finland
| | - Juha Halavaara
- Departments of Radiology, Helsinki University Central Hospital, Helsinki, Finland
| | - Asko Järvinen
- Divisions of Infectious Diseases, Helsinki University Central Hospital, Helsinki, Finland
| | - Matti Ristola
- Divisions of Infectious Diseases, Helsinki University Central Hospital, Helsinki, Finland
| | - Hannele Yki-Järvinen
- Department of Medicine, Divisions of Diabetes, Helsinki University Central Hospital, Helsinki, Finland
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Reusch JEB, Klemm DJ. Inhibition of cAMP-response element-binding protein activity decreases protein kinase B/Akt expression in 3T3-L1 adipocytes and induces apoptosis. J Biol Chem 2002; 277:1426-32. [PMID: 11694510 DOI: 10.1074/jbc.m107923200] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
White adipose tissue mass is governed by competing processes that control lipid synthesis and storage, the development of new adipocytes, and their survival. We have shown that the transcription factor cAMP-response element-binding protein (CREB) participates in adipogenesis, with constitutively active forms of CREB inducing adipocyte differentiation and dominant negative forms of CREB blocking this process. In other cell types, CREB and related factors have been shown to play important roles in survival and apoptosis. Here we demonstrate that reduction of CREB activity by ectopic expression of the dominant negative CREB, KCREB, induces apoptosis of mature 3T3-L1 adipocytes in culture. Death by apoptosis was confirmed by increased nuclear condensation, changes in membrane morphology, and increased DNA fragmentation. Gene microarray analysis indicated that KCREB expression increased expression of several pro-apoptotic genes like Interleukin Converting Enzyme and decreased the expression of the anti-apoptotic signaling molecule, Akt/protein kinase B. Finally, introduction of constitutively active CREB, CREB-DIEDML, blocked death of mature adipocytes treated with TNF-alpha. The data indicate that CREB plays a central role in adipocyte survival, perhaps by regulating the expression of certain pro- and anti-apoptotic genes. These results not only extend the role of CREB in adipocyte biology but also highlight the general developmental and survival role of this factor in numerous cell and tissue types.
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Affiliation(s)
- Jane E B Reusch
- Endocrinology and Pulmonary and Critical Sections, and Research Service, Veterans Affairs Medical Center, Denver, Colorado 80220, USA
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99
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Roche R, Poizot-Martin I, Yazidi CME, Compe E, Gastaut JA, Torresani J, Planells R. Effects of antiretroviral drug combinations on the differentiation of adipocytes. AIDS 2002; 16:13-20. [PMID: 11741158 DOI: 10.1097/00002030-200201040-00003] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Preadipocyte cell lines present a cell model with which to understand the physiopathological mechanisms underlying lipodystrophy syndrome, a common complication observed in patients treated with highly active antiretroviral therapy (HAART) that, in general, is associated with the use of protease inhibitors (PI) and nucleoside reverse transcriptase inhibitors (NRTI). The aim of this study was to evaluate the effects of NRTI and of PI and NRTI combinations in this cell model. METHODS The differentiation of 3T3-F442A cells was studied by monitoring the expression of specific genes in the presence of therapeutic concentrations of antiretroviral drugs. Messenger RNA (mRNA) was quantified by two reverse transcription-PCR-based methods. RESULTS In the presence of 2 microM saquinavir, 30 microM ritonavir or 1 microM zidovudine preadipocytes delayed their differentiation, whereas the use of 10 microM nelfinavir led to cell death. Indinavir (10 microM) promoted lipoprotein lipase expression whereas 1 microM lamivudine or 1 microM stavudine enhanced slightly the expression of the malic enzyme gene. However, the combination of indinavir, lamivudine and stavudine led to a large increase in both lipoprotein lipase and malic enzyme mRNA transcription whereas the combination of indinavir, lamivudine and zidovudine led to a 2.5-fold increase in the expression of the lipogenic malic enzyme gene. Similar potentiating effects of NRTI and PI were observed on the expression of the fatty acid synthase gene. CONCLUSIONS Our data suggest that, like PI (although to a lesser extent) NRTI interfere with the differentiation process of adipocytes. In addition, we demonstrate that the effects produced by combinations of NRTI and PI are different from those elicited by each drug separately. This point may be particularly relevant in understanding the physiopathological mechanisms underlying the lipodystrophic syndrome.
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Affiliation(s)
- Régis Roche
- INSERM Unit 476, School of Medicine of Marseilles, Marseilles, France
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100
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Fauvel J, Bonnet E, Ruidavets JB, Ferrières J, Toffoletti A, Massip P, Chap H, Perret B. An interaction between apo C-III variants and protease inhibitors contributes to high triglyceride/low HDL levels in treated HIV patients. AIDS 2001; 15:2397-406. [PMID: 11740190 DOI: 10.1097/00002030-200112070-00007] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND Long-term therapy with protease inhibitors (PI) is associated with hypertriglyceridaemia, low high-density lipoprotein (HDL) levels and accumulation of apolipoprotein (apo) E- and apo C-III-containing lipoproteins. OBJECTIVES To evaluate the impact, on this dyslipaemic phenotype, of three polymorphisms of the apo C-III gene: two on an insulin response element and one in the 3'-region. Apo E genotypes were evaluated also. DESIGN Sixty consecutive male patients attending the HIV follow-up consultation were included during a 3-month period. All patients received at least one PI. Apo C-III and apo E genotypes were determined. Besides routine bio-clinical examination, a detailed exploration of lipoproteins and of insulin secretion markers was carried out. METHODS Plasma lipoparticles, insulin, proinsulin and C-peptide were measured by specific immuno-assays. Determination of apo C-III genotypes (-455C/T, -482C/T and SstI) and of apo E alleles (epsilon2, epsilon3 and epsilon4) were performed by amplification and endonuclease digestion and were confirmed by allele-specific oligonucleotide hybridization. RESULTS Distribution of apo C-III alleles defined four major haplotypes. Carriers of the -455C variant had 30% lower levels of HDL-cholesterol than non-carriers. Plasma triglycerides increased according to the number of variant alleles. In multivariate analysis, a model including age, body mass index, clinical stage and treatment length, plasma insulin and apo C-III haplotypes explained around 43% of the HDL-cholesterol and triglycerides variability. Measurements of lipids before and after the use of PI demonstrated synergistic effects of the treatment and apo C-III variants on triglyceride levels. CONCLUSIONS Apo C-III polymorphisms might identify a genetic predisposition to develop dyslipidaemia under PI therapy.
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Affiliation(s)
- J Fauvel
- Laboratoire de Biochimie III and INSERM U 326-IFR 30-Institut Claude de Préval, Toulouse University Hospital, Toulouse-Cédex, France
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