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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Highly active antiretroviral therapy (HAART) has prolonged many patients' lives, but many cardiac sequelae of HIV are not affected by HAART and continue to develop even with treatment. In addition, HAART itself causes in a high proportion of patients a metabolic syndrome, characterized by lipodystrophy/lipoatrophy, dyslipidemia and insulin resistance that may be associated with an increase in coronary artery disease and stroke. Careful cardiovascular evaluation in the course of HIV disease can identify cardiac complications early enough to treat. All HIV-infected patients are candidates for antiretroviral therapy and patients already under treatment should undergo an assessment that includes the evaluation of the cardiovascular risk according to the available guidelines.
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PMID:Highly active antiretroviral therapy and the cardiovascular system: the heart of the matter. 1462 56

Peripheral fat loss, or lipoatrophy, has been reported as an emerging complication of long-term antiretroviral regimens, mainly when nucleoside analogues are included. However, lipoatrophy does not develop in the majority of nucleoside inhibitor-treated patients, leading to the investigation of factors other than drug effects alone as potential contributors to this complication. We conducted a retrospective cohort study study and analysis of repository plasma samples taken from HIV-infected patients being treated with their initial antiretroviral regimen. CD4 cell count and plasma tumor necrosis factor (TNF), soluble TNF receptors, and leptin levels were assessed and correlated with the development of lipoatrophy. The most significant treatment-related factor in this study of patients on their first drug regimen was duration of antiretroviral therapy, rather than type of nucleoside inhibitor treatment. No association was found between lipoatrophy and specific nucleoside inhibitors, including zidovudine and stavudine. A significant association between lipoatrophy was found for 2 nondrug risk factors: older age and lower pretherapy body mass index. Our results emphasize the need for keeping in mind the role of host factors in the generation of lipoatrophy.
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PMID:Host factors may be more important than choice of antiretrovirals in the development of lipoatrophy. 1464 24

A large case-control study finds that lipoatrophy is the predominant fat abnormality in HIV-infected patients, and a small randomized, placebo-controlled study finds benefit for rosiglitazone for insulin resistance.
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PMID:Meeting notes from the 2nd International AIDS Society Conference on HIV Pathogenesis and Treatment. Metabolic update: better defining lipodystrophy and treating insulin resistance. 1466 24

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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PMID:HIV protease inhibitor ritonavir induces lipoatrophy in male mice. 1470 51

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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PMID:In vitro suppression of the lipogenic pathway by the nonnucleoside reverse transcriptase inhibitor efavirenz in 3T3 and human preadipocytes or adipocytes. 1472 61

We undertook anthropometric assessments of 530 HIV-seropositive and 314 HIV-seronegative men in the Multicenter AIDS Cohort Study at a regular visit that occurred between 1 April and 30 September 1999. We found anthropomorphic differences that were independent of age: the 384 seropositive men receiving HAART had diminished body size and higher frequency and severity of body habitus abnormalities, particularly lipoatrophy, compared with the 314 seronegative men.
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PMID:Anthropometrics and examiner-reported body habitus abnormalities in the multicenter AIDS cohort study. 1499 38

Patients with HIV taking protease inhibitors were selected for the presence (five subjects) or absence (five subjects) of lipoatrophy. Following an overnight fast, subjects were given oral (2)H(2)O in divided doses (5 mL/kg body water), [U-(13)C(3)] propionate (10 mg/kg), and acetaminophen (1000 mg). Glucose (from plasma) or acetaminophen glucuronide (from urine) were converted to monoacetone glucose for (2)H NMR and (13)C NMR analysis. The fraction of plasma glucose derived from gluconeogenesis was not significantly different between groups. However, flux from glycerol into gluconeogenesis relative to glucose production was increased from 0.20 +/- 0.13 among subjects without lipoatrophy to 0.42 +/- 0.12 (P < 0.05) among subjects with lipoatrophy, and the TCA cycle contribution was reduced. Lipoatrophy was associated with an abnormal profile of glucose production as assessed by (13)C and (2)H NMR of plasma and urine.
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PMID:Glucose production pathways by 2H and 13C NMR in patients with HIV-associated lipoatrophy. 1506 35

As new therapies for HIV infection have been developed, some of the clinical focus related to AIDS and HIV infection has shifted from acute care, to more chronic issues. Some of these new clinical issues seem related to the HIV infection itself, while others seem to be side effects of therapeutic efforts. Metabolic abnormalities, such as dyslipidemia, insulin resistance, and lipodystrophy (LD) have been observed. The clinical importance of these is demonstrated by the increased prevalence of cardiovascular disease and diabetes in HIV infected persons. LD is a general term used to describe varying degrees of fat redistribution, including lipoatrophy and lipohypertrophy, in different body regions. Though LD was observed in persons with HIV infection before highly active treatment regimens were developed, the prevalence of LD has seemingly increased drastically with the widespread use of more active therapies. It has been postulated that protease inhibitors (PI), especially, are linked to the development of LD. This review will assess the epidemiologic information related to HIV-associated LD, and related metabolic syndromes. In addition, potential mechanisms accounting for these syndromes will be reviewed. In general, the available data do not define a single, definable etiology or mechanism explaining these clinical conditions, but suggest that these conditions are caused by a complex interaction potentially involving such things as the side effects of medications, alteration of immune function, and individual subject characteristics, such as body weight and baseline lipid level.
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PMID:HIV-related lipodystrophy and related factors. 1513 44

Following the introduction of highly active antiretroviral therapy (HAART), metabolic and morphological complications known as HIV associated lipodystrophy syndrome (HALS) have been increasingly common. The approaches to target these complications span from resistance exercise, diet and use of the antidiabetics metformin or glitazones to high dose recombinant human growth hormone therapy or switching antiretroviral regimen. When looking at the effect of switching therapy, focus has been addressed to protease inhibitor (PI) based regimens, as PI was the first component of HAART recognized to be correlated with the disfiguring body-alterations known as HALS. More recently, however, regimens containing nucleoside reverse-transcriptase inhibitors (NRTI) have attracted attention. Reviewing switch studies regarding metabolic parameters and body shape changes, certain trends emerge. Switching from PI, the metabolic complications such as dyslipidaemia and insulin resistance seem to be partly reversible, whereas the morphologic alterations appear to be unchanged. In studies in which NRTI's are switched, dyslipidaemia appears unaffected, but a modest improvement in peripheral lipoatrophy has been reported. However the results are often inconsistent and difficult to interpret, mostly because of limitations in study design, patient number and duration of follow-up. The need for larger, controlled, randomized, long-term studies is evident.
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PMID:Impact of switching antiretroviral therapy on lipodystrophy and other metabolic complications: a review. 1519 79

Fat redistribution associated with the use of antiretroviral therapy, which has been broadly termed 'lipodystrophy', incorporates distinct body composition changes including lipoatrophy (subcutaneous fat loss) as well as fat accumulation. This review examines the role of nucleoside reverse transcriptase inhibitor (NRTI) therapy in the overall context of lipodystrophy, providing converging evidence from observational cohort studies, clinical trials and pathological studies that lipoatrophy is strongly and specifically associated with the use of certain NRTI drugs (stavudine more than zidovudine), and that host factors also have a modulating effect on risk of NRTI-associated lipoatrophy. Implications for clinical assessment and management are also considered, within a broader contest that incorporates treatment efficacy as well as toxicity.
J HIV Ther 2004 May
PMID:The role of nucleoside reverse transcriptase inhibitors in the fat redistribution syndrome. 1523 74


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