Increased serum interferon alpha in HIV-1 associated lipodystrophy syndrome

Relationship Between Lipodystrophy, Body Composition, Metabolic Profile, and Serum Levels of Adipocytokines

Background: Despite the benefits in improving the clinical state of people living with HIV/aids (PLWHA), some side effects associated with the use of antiretroviral therapy (ART) are reported. Redistribution of body fat has been associated with treatment and is characterized by morphological changes, also known as lipodystrophy. The complications of metabolic and morphological changes in these individuals seem to increase the risk of cardiovascular disease. Adipocytokines are proteins that have essential functions in biological processes, in which the levels of these proteins are related to the pathogenesis of metabolic syndrome (MS) and cardiovascular disease. Recent studies have shown that such levels are generally modified in PLWHA, regardless of whether the treatment is established or not. An application of methods for body fat estimation in patients with fat redistribution, as in the case of aids, especially those that quantify body fat by segments, appears to clarify these alterations and plays an important role in the development of multiprofessional treatment. Objectives: This investigation was carried out to compare and correlate body composition, biochemical metabolic parameters, and levels of adipocytokines and cytokines of PLWHA, with and without lipodystrophy, with individuals with negative HIV serology and stratified by sex. Material and Methods: This is a cross-sectional study in which body composition, metabolic and anthropometric changes, and levels of adipocytokines of 110 individuals were assessed. These individuals were paired in sex, age, and body mass index (BMI) and subdivided into three groups: PLWHA with and without a clinical diagnosis of lipodystrophy associated with HIV, and a group control. Results: Collinearity was identified both in the general sample and for genders of the waist-to-height ratio (WHtR) with all anthropometric parameters, except for muscle mass. The results show strong association between IFN-γ and TNF-α both in the general sample and for genders and moderate correlation between leptin and fasting glucose for women; worsening of the triglyceride profile in both women with lipodystrophy compared with the control group and men without lipodystrophy compared with the control group; higher serum TNF-α values among men without lipodystrophy compared to those with HIV-associated lipodystrophy (HALS). Conclusions: The results of this study underline that, considering the manifestations of the syndrome, these patients have a high-risk endocrine metabolic profile for cardiovascular events.

Combined Exercise Modulates Cortisol, Testosterone, and Immunoglobulin A Levels in Individuals Living With HIV/AIDS

BACKGROUND

Combined exercise (CE) has been recommended for individuals living with HIV/AIDS (ILWHA) under antiretroviral therapy. However, depending on the intensity and duration, physical exercise may occasionally increase inflammatory parameters and reduce immunological responses that if not reversed, cause health injury specifically in this population. Information about immunological and hormonal responses after CE in ILWHA has not been completely elucidated. Therefore, the aim is to verify the acute effects of CE on cortisol, testosterone, immunoglobulin A, and pro-inflammatory and anti-inflammatory cytokines over 24 hours in ILWHA.

METHODS

Noninfected individuals and ILWHA undergone 5 sessions of CE prior to the acute assessment session. Seventy-two hours after the last session, the subjects were submitted to one session of CE (aerobic exercise: 25 min at 60-70% reserve heart rate and resistance exercise: 3 sets of 15 maximum repetitions of 6 exercises). Saliva samples were collected before, immediately, 6 and 24 hours after CE.

RESULTS

CE reduced cortisol (6 h: 2.54 [0.58] vs 0.65 [0.22] pg·mL-1; P = .02), increased testosterone (all moments) and immunoglobulin A levels (24 h: 255.3 [44.7] vs 349.2 [41.9] μm·mL-1; P = .01) without significant difference in cytokines levels in ILWHA.

CONCLUSION

CE modulates cortisol, testosterone, and immunoglobulin A levels without the change in immunological parameters in ILWHA.

Interferon-alpha 2 but not Interferon-gamma serum levels are associated with intramuscular fat in obese patients with nonalcoholic fatty liver disease

BACKGROUND

Intramuscular triglycerides (IMTGs) represent an important energy supply and a dynamic fat-storage depot that can expand during periods of elevated lipid availability and a fatty acid source. Ultrasonography (US) of human skeletal muscles is a practical and reproducible method to assess both IMTG presence and entity. Although a crosstalk between cytokines in skeletal muscle and adipose tissue has been suggested in obesity, condition leading to hepatic steatosis (HS) or better defined as nonalcoholic fatty liver disease and cancer, there are still questions to be answered about the role of interferons (IFNs), alpha as well as gamma, and IMTG in obesity. We aimed at discovering any correlation between IFNs and IMTG.

METHODS

We analysed anthropometric data, metabolic parameters and imaging features of a population of 80 obese subjects with low-prevalence of co-morbidities but HS in relation to IFNs serum levels. A population of 38 healthy subjects (21 males) served as controls. The levels of serum IFNs were detected by a magnetic bead-based multiplex immunoassays.

RESULTS

Serum concentrations of IFN-alpha 2 were increased, while serum levels of IFN-gamma were decreased confronted with those of controls; the severity of IMTG, revealed at US as Heckmatt scores, was inversely predicted by IFN-alpha 2 serum concentrations; IMTG scores were not predicted by serum levels of IFN-gamma; IMTG scores were predicted by HS severity, ascertained at US; HS severity was predicted by visceral adipose tissue, assessed by US, but the latter was not instrumental to IMTG.

DISCUSSION AND CONCLUSION

This study has added some pieces of observation about the cytokine network regulating the interplay between IMTG and obesity in obese patients with HS.

The dawn of precision medicine in HIV: state of the art of pharmacotherapy

INTRODUCTION

Combination antiretroviral therapy (ART) reduces viral load to under the limit of detection, successfully decreasing HIV-related morbidity and mortality. Due to viral mutations, complex drug combinations and different patient response, there is an increasing demand for individualized treatment options for patients.

AREAS COVERED

This review first summarizes the pharmacokinetic and pharmacodynamic profile of clinical first-line drugs, which serves as guidance for antiretroviral precision medicine. Factors which have influential effects on drug efficacy and thus precision medicine are discussed: patients' pharmacogenetic information, virus mutations, comorbidities, and immune recovery. Furthermore, strategies to improve the application of precision medicine are discussed.

EXPERT OPINION

Precision medicine for ART requires comprehensive information on the drug, virus, and clinical data from the patients. The clinically available genetic tests are a good starting point. To better apply precision medicine, deeper knowledge of drug concentrations, HIV reservoirs, and efficacy associated genes, such as polymorphisms of drug transporters and metabolizing enzymes, are required. With advanced computer-based prediction systems which integrate more comprehensive information on pharmacokinetics, pharmacodynamics, pharmacogenomics, and the clinically relevant information of the patients, precision medicine will lead to better treatment choices and improved disease outcomes.

Lower levels of IL-4 and IL-10 influence lipodystrophy in HIV/AIDS patients under antiretroviral therapy

BACKGROUND

The role of interleukins in the pathogenesis of lipodystrophy in HIV/AIDS-patients is still not understood. The aim of this study was to evaluate the relationship between serum levels of interleukins between HIV/AIDS-patients with or without lipodystrophy, as well as between different subgroups of lipodystrophy (lipoatrophy, lipohypertrophy, mixed-fat-redistribution) and patients without lipodystrophy.

METHODS

Cross-sectional study of 66 HIV/AIDS patients, all Caucasians. Serum levels of interleukins (IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10) were measured using Cytokine-Array-1 on Evidence Investigator, Biochip Array Technology. The associations between interleukins and anthropometric and metabolic variables were estimated by Spearman-correlation. Analysis of covariance with bootstrapping method (ACBM) was used to examine relationship between interleukins and lipodystrophy categories adjusted for confounding variables.

RESULTS

The lipodystrophy was observed in 29 (44%) patients, while 15 (52%) had lipoatrophy, 4 (14%) lipohypertrophy and 10 (34%) patients had mixed fat redistribution. There were 37 (56%) patients without lipodystrophy. Significantly lower levels of IL-4 and IL-10 were observed in lipodystrophy vs. non-lipodystrophy (p=0.008; p=0.027, respectively). No differences were found relating IL-1α, IL-1β, IL-2, IL-6 and IL-8 levels in lipodystrophy vs. non-lipodystrophy. In patient subgroup with lipoatrophy, significantly lower levels of IL-4 and IL-10 were found when compared to non-lipodystrophy (p=0.043; p=0.031, respectively). In lipohypertrophy subgroup significantly lower levels of IL-4 were found when compared to non-lipodystrophy (p=0.003). In order to estimate the correlation of IL-4 and IL-10 and the presence of lipodystrophy, ACBM showed that correlation of IL-4 levels in patients with lipodystrophy remains statistically significant (p=0.004) in all types of lipodystrophy: lipoatrophy, lipohypertrophy and mix-fat-redistribution (p=0.027; p=0.009; p=0.017, respectively) after adjustment for age, BMI.

CONCLUSIONS

IL-4 and IL-10 levels were significantly lower in lipodystrophy vs. non-lipodystrophy. According to our knowledge, we showed for the first time significant correlation between IL-4 levels and lipodystrophy development in HIV/AIDS patients.

Lipid profile of HIV-infected patients in relation to antiretroviral therapy: a review

This study reviewed the lipid profile of human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) patients in relation to use of antiretroviral therapy (ART), and its different classes of drugs. A total of 190 articles published in peer-reviewed journals were retrieved from PubMed and LILACS databases; 88 of them met the selection criteria and were included in the review. Patients with HIV/AIDS without ART presented an increase of triglycerides and decreases of total cholesterol, low density lipoprotein (LDL-c), and high density lipoprotein (HDL-c) levels. Distinct ART regimens appear to promote different alterations in lipid metabolism. Protease inhibitors, particularly indinavir and lopinavir, were commonly associated with hypercholesterolemia, high LDL-c, low HDL-c, and hypertriglyceridemia. The protease inhibitor atazanavir is apparently associated with a more advantageous lipid profile. Some nucleoside reverse-transcriptase inhibitors (didanosine, stavudine, and zidovudine) induced lipoatrophy and hypertriglyceridemia, whereas abacavir increased the risk of cardiovascular diseases even in the absence of apparent lipid disorders, and tenofovir resulted in lower levels of cholesterol and triglycerides. Although non-nucleoside reverse-transcriptase inhibitors predisposed to hypertriglyceridemia and hypercholesterolemia, nevirapine was particularly associated with high HDL-c levels, a protective factor against cardiovascular diseases. Therefore, the infection itself, different classes of drugs, and some drugs from the same class of ART appear to exert distinct alterations in lipid metabolism.

Pathophysiology of the HIV-Associated Lipodystrophy Syndrome

The widespread use of highly active antiretroviral therapy (HAART) has radically transformed the prognosis of HIV-infected patients in the developed countries. Unfortunately, a serious metabolic syndrome combining peripheral lipoatrohy, central adiposity, insulin resistance, and dyslipidemia has arisen in these individuals. The etiology of this heterogeneous syndrome named lipodystrophy syndrome (LDS) is multifactorial, but adipose tissue is very likely a key factor that contributes to several clinical or metabolic aspects of the syndrome. In peripheral adipose tissue, HAART may act on both preadipocytes and adipocytes to induce fat loss. Several components of the HAART regimen can inhibit preadipocyte differentiation, in particular through alterations in the expression and/or function of the transcription factor sterol responsive element binding protein-1c. In superficial mature adipocytes, HAART promotes insulin resistance and apoptosis. Insulin resistance of peripheral fat cells could be the consequence of increased lipolysis and adipocytokine dysregulation. In turn, the increased free fatty acid disposal and the disturbances in adipocytokine production may induce skeletal muscle and liver insulin resistance, dyslipidemia, and a fat redistribution toward deep depots, causing visceral lipohypertrophy. The metabolic profile observed in LDS is reminiscent of that observed in metabolic syndrome, raising potential implications for cardiovascular risk in these patients. The pathophysiological mechanisms at the basis of this syndrome represent a rational basis for the treatment or prevention of the metabolic complications.

No relationship between TNF-α genetic variants and combination antiretroviral therapy-related lipodystrophy syndrome in HIV type 1-infected patients: a case-control study and a meta-analysis

Tumor necrosis factor alpha (TNF-α) is thought to be involved in the pathogenic and metabolic events associated with HIV-1 infection. We assessed whether carriage of the TNF-α gene promoter single nucleotide polymorphism (SNP) is associated with lipodystrophy and metabolic derangements in HIV-1-infected patients treated with cART. We also assessed variations in TNF-α receptor plasma levels. The study group comprised 286 HIV-1-infected patients (133 with and 153 without lipodystrophy) and 203 uninfected controls (UC). TNF-α -238G > A, -308G > A, and -863 C > A SNP were assessed using PCR-RFLPs on white cell DNA. Plasma sTNF-α R1 and R2 levels were measured by ELISA. Student's t test, the χ(2) test, Pearson correlations, and the logistic regression test were performed for statistical analysis. The TNF-α -308G > A SNP was significantly associated with lipodystrophy in the univariate analysis (p = 0.04). This association, however, was no longer significant in the multivariate analysis. A meta-analysis of the published literature and our own data, which included 284 patients with lipodystrophy and 338 without lipodystrophy, showed that there was no relationship between the TNF-α -238G > A and -308G > A SNP and lipodystrophy (p > 0.05 for all comparisons). HIV-1-infected patients had greater sTNF-α R2 plasma levels than UC (p = 0.001) whereas sTNF-α R1 and R2 levels were not significantly different in both the HIV-1-infected cohorts, lipodystrophy vs. nonlipodystrophy (p = NS). In our cohort of white Spaniards the TNF-α -238G > A, -308G > A, and -863C > A SNP were not associated with lipodystrophy in HIV-1-infected patients treated with cART. This finding was replicated in a meta-analysis of the published data, which showed no associations between the TNF-α -238G > A and -308G > A SNP and lipodystrophy. In HIV-1-infected patients under cART there is a systemic overproduction of sTNF-α R2, which is unrelated to the presence of lipodystrophy.

Interleukin-18 and interferon-gamma polymorphisms in Brazilian human immunodeficiency virus-1-infected patients presenting with lipodystrophy syndrome

Cytokines play important roles in the pathogenesis of lipodystrophy syndrome (LS). Single nucleotide polymorphisms (SNPs) at positions -607(C/A) and -137(C/G) in the promoter region of the interleukin-18 (IL-18) gene and at position +874(T/A) of the interferon-gamma (IFN-gamma) gene are related to the expression of these cytokines. To examine whether IL-18 and IFN-gamma polymorphisms are associated with LS, these SNPs were genotyped in 88 human immunodeficiency virus (HIV)-infected patients presenting LS, 79 HIV-infected without LS, and 133 healthy controls. The -607A allele, -607AA genotype, and -137G/-607A and -137C/-607A haplotypes in the IL-18 gene were over-represented in HIV patients presenting LS. The -137G/-607C haplotype was associated with protection against LS. These results indicate that the -607(C/A) SNP is associated with LS development in HIV-infected patients.

IL-1beta (+3954C/T) polymorphism could protect human immunodeficiency virus (HIV)-infected patients on highly active antiretroviral treatment (HAART) against lipodystrophic syndrome

PURPOSE

To evaluate the impact of acquired and inherited factors on the development of lipodystrophic syndrome in patients on highly active antiretroviral therapy.

METHODS

Two hundred forty-three human immunodeficiency virus-infected Caucasians on highly active antiretroviral therapy were prospectively followed-up for 3 years. Eleven were naIve and 232 were on antiretrovirals (mean, 93.0 months +/- 43.8 months). Lipodystrophic syndrome was diagnosed clinically with a lipodystrophy severity grading scale. Polymorphisms of cytokines (IL-1beta, IL-6, TNF-alpha), TLR4, and NOS genes were genotyped.

RESULTS

Ninety (37%) patients developed lipodystrophic syndrome. The polymorphic T allele of the (+3954C/T) polymorphism of IL-1beta was less frequent in patients with lipodystrophic syndrome compared with those without (17.8% vs. 27.0%, P = 0.03). Factors significantly associated with lipodystrophic syndrome were time on stavudine (P < 0.001), use of stavudine (P = 0.001), absence of the T allele of the (+3954C/T) IL-1beta polymorphism (P = 0.02), acquired immune deficiency syndrome diagnosis (P = 0.005), nadir levels of CD4 (P = 0.003), and time on highly active antiretroviral therapy (P = 0.003). Of these factors, only the time on stavudine (hazard ratio [95% confidence intervals] 1.007 [1.001-1.013]), use of stavudine (1.678 [1.048-2.68]), and absence of the T allele of the IL-1beta (+3954C/T) polymorphism (0.569 [0.347-0.931]) were significantly associated with lipodystrophic syndrome by Cox regression.

CONCLUSIONS

Genotyping of the (+3954C/T) polymorphism of IL-1beta could be useful in patients starting highly active antiretroviral therapy, especially in potential users of stavudine, to predict their risk of developing lipodystrophic syndrome.

Serum leptin concentrations and fat redistribution in HIV-1-infected children on highly active antiretroviral therapy

OBJECTIVES

HIV-related lipodystrophy is a syndrome of adipose tissue redistribution, dyslipidaemia and insulin resistance. Combination antiretroviral therapy (CART) is a key risk factor. We hypothesized that fat redistribution in HIV-infected children is related to altered endocrine function of adipose tissue, namely leptin secretion.

METHODS

Serum leptin and fat redistribution were measured in 104 HIV-infected children in a prospective observational study from 2003 to 2004. Fat redistribution was defined by clinical observation. Body fatness was estimated using body mass index and four skinfold measurements. Serum leptin was determined using an enzyme-linked immunosorbent assay (Quantikine; R&D Systems, Abingdon, UK). Linear analogue models were used to adjust the leptin concentration for body fatness.

RESULTS

There was no significant difference in serum leptin among children treated with protease inhibitors (PIs), children on non-PI CART and children not treated with CART (P>0.05). When leptin concentrations were adjusted for body fatness, there was again no difference among PI-treated, non-PI-treated and untreated children. Categorization of CART exposure as never, current or past did not change these results.

CONCLUSIONS

There is no evidence that leptin plays any role in lipodystrophy other than reflecting body fatness.

An interferon-alpha-induced tethering mechanism inhibits HIV-1 and Ebola virus particle release but is counteracted by the HIV-1 Vpu protein

Type 1 interferon (IFN) inhibits the release of HIV-1 virus particles via poorly defined mechanisms. Here, we show that IFNalpha induces retention of viral particles on the surface of fibroblasts, T cells, or primary lymphocytes infected with HIV-1 lacking the Vpu protein. Retained particles are tethered to cell surfaces, can be endocytosed, appear fully assembled, exhibit mature morphology, and can be detached by protease. Strikingly, expression of the HIV-1 Vpu protein attenuates the ability of human cells to adhere to, and thereby retain, nascent HIV-1 particles upon IFNalpha treatment. Vpu also counteracts the IFNalpha-induced retention of virus-like particles assembled from the Ebola virus matrix protein. Furthermore, levels of IFNalpha that suppress replication of Vpu-defective HIV-1 have little effect on wild-type HIV-1. Thus, we propose that HIV-1 expresses Vpu to counteract an IFNalpha-induced, general host defense that inhibits dissemination of enveloped virions from the surface of infected cells.

Insulin resistance, glucose intolerance and diabetes mellitus in HIV-infected patients

An increased prevalence of insulin resistance, glucose intolerance and diabetes has been reported in HIV infection in the highly active antiretroviral therapy (HAART) era. This development might be clinically significant because of its association with cardiovascular morbidity and mortality as well as the therapeutic challenges of managing polypharmacy. The development of insulin resistance, glucose intolerance and diabetes could be related to the underlying HIV infection, the contribution of different antiretroviral agents, treatment-associated weight gain, immune restoration, as well as the non-HIV related factors. Dissecting these factors in clinical practice might be difficult. Clinical studies include short-term treatments in healthy, non-HIV-infected individuals; randomized, controlled trials; comparative studies of different HAART regimens; and randomized studies of switching regimens in patients with viral suppression and stable immune function. This article reviews the latest knowledge regarding the epidemiology, pathogenesis, prevention and treatment of insulin resistance, glucose intolerance and diabetes mellitus in HIV-infected individuals.

Reduction in triglyceride level with N-3 polyunsaturated fatty acids in HIV-infected patients taking potent antiretroviral therapy: a randomized prospective study

To assess the evolution of triglyceride (TG) levels in HIV-infected patients receiving stable potent antiretroviral therapy treated with N-3 polyunsaturated fatty acids (PUFAs), a prospective double-blind randomized design for a reliable assessment of TG evolution was performed. One hundred twenty-two patients with TG levels >2 g/L and < or =10 g/L after a 4-week diet (baseline TG: 4.5 +/- 1.9 g/L) were randomized for 8 weeks to N-3 PUFAs (2 capsules containing 1 g of fish oil 3 times daily, n = 60), or placebo (1 g of paraffin oil capsules, n = 62). An 8-week open-label phase of N-3 PUFAs followed. Evaluation criteria were TG percent change at week 8, percentage of responders (normalization or > or =20% TG decrease), and safety issues. Ten patients with baseline TG levels >10 g/L were not randomized and received N-3 PUFAs as open treatment. The difference (PUFA - placebo) in TG percent change at week 8 was -24.6% (range: -40.9% to -8.4%; P = 0.0033), the median was -25.5% in the PUFA group versus 1% in the placebo group, and mean TG levels at week 8 were 3.4 +/- 1.8 g/L and 4.8 +/- 3.1 g/L, respectively. TG levels were normalized in 22.4% (PUFA) versus 6.5% (placebo) of patients (P = 0.013) with a > or =20% reduction in 58.6% (PUFA) versus 33.9% (placebo) of patients (P = 0.007). Under the open-label phase of N-3 PUFAs, the decrease in TG levels was sustained at week 16 for patients in the PUFA group (mean TG: 3.4 +/- 1.7 g/L), whereas a 21.2% decrease in TG levels occurred for patients in the placebo group (mean TG: 3.3 +/- 1.4 g/L). No significant differences were observed between groups in the occurrence of adverse events. The median TG change at week 8 was -43.6% (range: Q1-Q3; 95% CI: -66.5% to -4.6%) for patients with baseline TG levels >10 g/L. The difference in mean total cholesterol between groups (PUFA - placebo) at week 8 was -8.5% (P = 0.0117). This study demonstrated the efficacy of PUFAs to lower elevated TG levels in treated HIV-infected hypertriglyceridemic patients. N-3 PUFAs have a good safety profile.

Venous and arterial thrombosis in patients with HIV infection

Thromboembolic complications in HIV-infected patients have been reported. To our knowledge, no case-control studies have compared the prevalence of thromboembolic events between HIV-positive and HIV-negative individuals. One hundred and sixty-nine HIV-infected patients and 180 randomly selected blood donors were enrolled. Selected patients completed a specific questionnaire and were subsequently interviewed. Information was collected on family and personal history of cardiovascular disorders and the presence of personal risk factors for venous and arterial thrombosis. All reported events were adjudicated only if adequate documentation of objective tests was available. Mean age and sex were similar in the two groups. A vascular event was documented in six HIV-infected patients (3.55%) and in none of the controls (P=0.0108). Family history of cardiovascular disorders, cigarette smoking and hypertriglyceridemia were more prevalent in HIV patients than in controls. In multivariate analysis, neither family traditional cardiovascular risk factors nor HIV infection were independently associated with the presence of thromboembolic events. The results confirm the hypothesis that HIV-positive patients have an increased risk of thromboembolic disorders. Whether this increased risk has been provoked by HIV infection itself or by other associated risk factors for cardiovascular events, such as cigarette smoking and hypertriglyceridemia, remain to be clarified.

Hypoadiponectinemia, dyslipidemia, and impaired growth in children with HIV-associated facial lipoatrophy

OBJECTIVE

To compare growth, lipids and adipocytokines in HIV-positive children with and without lipoatrophy.

PATIENTS

Eleven HIV-positive children with facial lipoatrophy, and 22 age- and sex-matched HIV-positive controls without signs of fat abnormality.

METHODS

Clinical data including height, physical examination findings, medications, markers of viral control, cholesterol, and triglycerides were retrieved from the medical charts. Serum samples were analyzed for adiponectin, inflammatory markers, and high density lipoprotein cholesterol (HDL).

RESULTS

Lipoatrophy was associated with higher triglycerides (330 vs 133 mg/dl, p = 0.0003), lower HDL (33 vs 48 mg/dl, p = 0.02), and a greater frequency of hypercholesterolemia (total cholesterol > 200 mg/dl; 64% vs 23%, p < 0.03). Adiponectin was 53% lower in patients with lipodystrophy (6.9 microg/ml vs 14.8 microg/ml, p = 0.005), however there was no difference in the inflammatory markers soluble TNFa receptor 2 or interleukin 6. Strikingly, despite similar BMI z-scores and virological control, lipoatrophic patients were shorter by 1 standard deviation score (p = 0.03).

CONCLUSIONS

The presence of facial lipoatrophy in a child with HIV infection is a marker for significant metabolic derangements including dyslipidemia and hypoadiponectinemia, and suggests the need for careful growth evaluation.

Low interleukin-10 production is associated with diabetes in HIV-infected patients undergoing antiviral therapy

Reduced interleukin-10 (IL-10) production is associated with type 2 diabetes in elderly individuals. Antiviral therapy (ARV)-induced immune modulation results in diminished IL-10 production, and diabetes can be observed in ARV-treated human immunodeficiency virus (HIV)-infected individuals. We analyzed, in a cross-sectional pilot study, HIV-antigen-stimulated IL-10 and tumor necrosis factor alpha (TNFalpha) production, and intracellular concentration (ICC), as well as B7-H1 expression, a marker preferentially presented by IL-10-producing cells, in 20 ARV-treated individuals in whom diabetes did (n=10; diabetes mellitus, DM) or did not (n=10; controls) develop. Pre-ARV glucose, cholesterol, and triglycerides levels, duration of HIV infection and of therapy, exposure to protease inhibitors (PI), HIV plasma viremia, CD4 counts, and nadir were similar in DM and control patients. Results showed that: (1) IL-10 production was lower; (2) IL-10 ICC was reduced; (3) B7-H1-expressing CD19(+) cells were diminished; and (4) TNFalpha production and ICC by CD4(+) T cells was augmented in DM patients. Development of diabetes in HIV infected, ARV-treated individuals could be a response to therapy. Similar to what is observed in elderly individuals, low IL-10 production is associated with diabetes in antiviral-treated HIV infection. Further studies will be necessary to clarify whether low IL-10 is a risk factor for, or a consequence of, diabetes.

Tumour necrosis factor alpha in fat redistribution syndromes associated with combination antiretroviral therapy in HIV-1-infected patients: potential role in subcutaneous adipocyte apoptosis

BACKGROUND

The pathogenesis of fat redistribution syndromes (FRS) observed in the setting of highly active antiretroviral therapy (HAART) for the treatment of HIV-1-infection remains elusive. A dysregulation of the tumour necrosis factor alpha (TNF-alpha) system occurs in HIV-infected patients with FRS.

MATERIALS AND METHODS

The study looked at both the in vivo and in vitro relationship between TNF-alpha and the degree of subcutaneous adipocyte apoptosis in 60 HIV-1-infected patients on HAART with FRS, another 60 HIV-1-infected patients on HAART without FRS and 60 uninfected control patients. Apoptosis was assessed by the terminal deoxynucleotidyl transferase dUTP (deoxyuridine 5'-triphosphate)-digoxigenin Nick End Labelling (TUNEL) method. Soluble receptors of TNF-alpha were determined by the sandwich enzyme immunoassay technique. The in vitro viability was assessed by staining with 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) and apoptosis by TUNEL.

RESULTS

HIV-1-infected patients with FRS had significantly higher degrees of subcutaneous adipocyte apoptosis than those without FRS (P = 0.0001) and uninfected controls (P < 0.0001). There was a statistically significant association between serum levels of soluble TNF-alpha receptors #1 and #2 and the degree of subcutaneous adipocyte apoptosis in patients with and without FRS (P < 0.0001 for both receptors). In vitro, the addition of TNF-alpha (10 ng mL(-1)) to an adipocyte culture embedded with indinavir, either alone or in clinically relevant combinations with stavudine (d4T) and lamivudine (3TC), significantly decreased adipocyte viability (P = 0.0001) and increased adipocyte apoptosis (P < 0.0001) with respect to that observed with the addition of antiretrovirals alone.

CONCLUSIONS

TNF-alpha plays a significant role in subcutaneous adipocyte apoptosis, which occurs in the setting of FRS in HIV-1-infected patients on highly active antiretroviral therapy.

HIV antiretroviral treatment alters adipokine expression and insulin sensitivity of adipose tissue in vitro and in vivo

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.

Dyslipidemia and inflammation: an evolutionary conserved mechanism

Inflammation leads to changes in lipid metabolism aimed at decreasing the toxicity of a variety of harmful agents and tissue repair by redistributing nutrients to cells involved in host defence. Acute phase response, mediated by cytokines, preserves the host from acute injury. When this inflammation becomes chronic, it might lead to chronic disorders as atherosclerosis and the metabolic syndrome. The activation of the inflammatory cascade will induce a decrease in HDL-cholesterol (HDL-C), with impairment in reverse cholesterol transport, and parallel changes in apolipoproteins, enzymes, anti-oxidant capacity and ATP binding cassette A1-dependent efflux. This decrease in HDL-C and phospholipids could stimulate compensatory changes, as synthesis and accumulation of phospholipid-rich VLDL which binds bacterial products and other toxic substances, resulting in hypertriglyceridemia. The final consequence is an increased accumulation of cholesterol in cells. When the compensatory response (inflammation) is not able to repair injury, it turns into a harmful reaction, and the lipid changes will become chronic, either by repeated or overwhelming stimulus, enhancing the formation of atherosclerotic lesions. Thus, the classical lipid changes associated with the metabolic syndrome (increased triglycerides and decreased HDL-C) may be envisioned as a highly conserved evolutionary response aimed at tissue repair. Under this assumption, the problem is not the response but the persistence of the stimulus.

Antiretroviral Drugs with Adverse Effects on Adipocyte Lipid Metabolism and Survival Alter the Expression and Secretion of Proinflammatory Cytokines and Adiponectin In Vitro

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.

Anti-cytokine Ab immune therapy: present status and perspectives

Allergy, autoimmunity and the pathogenesis of some chronic diseases are dependent on host innate and adaptative immune responses. Both responses are associated with abnormal cytokine production within pathologic tissues. Over the past two decades, the availability of purified cytokines and cytokine antibodies (Abs) has prompted a therapeutic approach that aims to supply neutralizing Abs against deleterious cytokines, through either passive immunization (administration of large quantities of high affinity Abs, prepared ex vivo) or active immunization (induction of specific Abs, using immunogenic cytokine derivatives). Both passive and active immunization can safely, transiently and effectively be used, as has been documented by animal experimentation and confirmed by clinical trials. Novel anti-cytokine therapeutic compounds, based on passive Ab immunization, are now available to treat rheumatoid arthritis (RA) and have been shown to help control neoangiogenesis in cancer patients. Clinical trials using Abs to treat allergic disorders are also underway. However, the induction of anti-idiotypic Abs may restrict the long-term use of anti-cytokine immunotherapy using allogenic or humanized/chimeric Abs. We propose that greater consideration should be given to active immunization protocols.

HIV-related lipodystrophy and related factors

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.

The cellular pharmacology of nucleoside- and nucleotide-analogue reverse-transcriptase inhibitors and its relationship to clinical toxicities

Nucleoside- and nucleotide-analogue reverse-transcriptase inhibitors (NRTIs) require intracellular phosphorylation for anti-human immunodeficiency virus (HIV) activity and toxicity. Long-term toxicities associated with NRTIs may be related to overactivation of this process. In vitro experiments have shown increased rates of NRTI and endogenous nucleoside phosphorylation to be associated with cellular activation. Patients with advanced HIV disease often have overexpression of cytokines, which corresponds to an elevated cellular activation state. These patients also have higher rates of NRTI phosphorylation and NRTI toxicity, suggesting an interaction between a proinflammatory biological state, NRTI phosphorylation, and toxicity. Studies suggest that women may have higher rates of NRTI phosphorylation than do men, as well as increased risk for NRTI-induced toxicity. Future research is needed to understand the NRTI activation process and improve the long-term toxicity profile of NRTIs. Such research should include comparisons of NRTI phosphorylation according to sex and cellular activation state (i.e., elevated vs. low).

Adipocytes Targets and Actors in the Pathogenesis of HIV-Associated Lipodystrophy and Metabolic Alterations

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.

HIV Lipodystrophy Syndrome: A Primer

Treatment with highly active antiretroviral therapy (HAART) has been implicated in the development of anthropomorphic and metabolic abnormalities termed HIV lipodystrophy syndrome (or LDS). This primer offers a comprehensive overview of LDS including epidemiology, hypothesized etiologies, and clinical consequences. The evidence-based literature is reviewed for current treatment strategies including discontinuation of specific antiretrovirals, pharmacological management of dyslipidemia and insulin resistance, exercise training, facial augmentation, liposuction, and hormonal therapy. Patient education, counseling, and adherence are discussed.

[Adverse effects of antiretroviral therapy. Aspects of pathogenesis]

Highly active antiretroviral therapy has resulted in remarkable reduction of morbidity and mortality of HIV infection. With increasing duration of therapy metabolic alterations such as hyperlipidemia, diabetes mellitus type 2 and lipodystrophy are encountered which considerably reduced quality of life for the patients. These adverse events are most likely due to protease inhibitors and nucleoside analogues with synergistic effects. The pathogenesis is related to metabolic alterations of the adipocytes with cellular insulin resistance and enhanced apoptosis of these cells caused by adipocytic cytokines such as adiponectin, leptin, TNF-alpha and interleukin 2. Switch of therapy regimens with elimination of the most suspicious substances and certain protease inhibitors can lead to improvement of deranged metabolism. Also symptomatic therapy is possible to cope with hyperlipidemia and diabetes, although no effective treatment is available to reverse already existing lipodystrophy. Our knowledge about the pathogenesis of these alterations might lead to new concepts and causal therapy in the future.

Altered Fat Differentiation and Adipocytokine Expression are Inter-Related and Linked to Morphological Changes and Insulin Resistance in HIV-1-Infected Lipodystrophic Patients

Objective

To achieve a better understand of the pathophysiology of HIV-related lipoatrophy, we compared the mRNA expression of adipocytokines in fat samples from patients and healthy HIV-seronegative controls together with fat morphology and we studied the relationship between changes in fat morphology, adipocytokine expression, markers of adipose tissue differentiation and whole body insulin sensitivity.

Design

Cross-sectional analytical study.

Subjects and methods

The mRNA expression of adipocytokines and transcriptional factors in fat samples from 26 patients with peripheral lipoatrophy (all under anti-retroviral therapy associating protease inhibitor and nucleoside-analogue reverse transcriptase inhibitors) and from 16 non-HIV-infected controls was measured by real time quantitative RT-PCR. Fat morphology was assessed histologically on a subgroup of 10 patients and six controls: collagen fibres by Sirius Red staining, apoptosis by the TUNEL technique, vessels by smooth muscle α-actin staining and macrophages by CD68 staining. Insulin resistance was assessed by using the homeostasis model assessment.

Results

The patients’ fat showed higher values of apoptosis ( P=0.005), fibrosis ( P<0.05), vessel density ( P=0.001) and macrophage infiltration ( P<0.05) than the controls’ fat, together with lower adiponectin and leptin mRNA levels and higher interleukin (IL)-6 and tumour necrosis factor (TNF)α mRNA levels. TNFα and IL-6 expression correlated positively with the level of apoptosis ( P=0.05 and P<0.05, respectively) and negatively with CCAAT-enhancer binding protein (C/EBP)α ( P<0.001 and P<0.05, respectively). Apoptosis correlated negatively with the expression level of sterol-regulatory-element-binding-protein-1c (SREBP1c) ( P=0.01) and C/EBPα ( P=0.01) whilst the vessel density correlated negatively with SREBP1c ( P<0.005), C/EBPα ( P=0.001) and β ( P=0.001). Adiponectin and leptin expression correlated positively with each other, and also with adipogenic marker expression and overall insulin sensitivity. These relationships were also present when the patient group was studied separately. Finally, fat morphological abnormalities correlated positively with whole body insulin resistance.

Conclusions

Adipose tissue from patients with HIV-1-related lipoatrophy shows increased apoptosis, together with decreased adipocyte differentiation. Increased TNFα and IL-6 expression could be a major phenomenon linking these alterations. Decreased adiponectin and leptin expression, which may result from decreased adipocyte differentiation, could be involved in the observed whole body insulin resistance.

Serum albumin is a powerful predictor of survival among HIV-1-infected women

BACKGROUND

We previously reported that single measurements of albumin strongly predict survival in HIV-1-infected women independent of disease-specific markers. We now extend this to the use of serial measurements and single albumin values prior to initiation of highly active antiretroviral therapy.

DESIGN

Prospective cohort study of 1941 women enrolled at six sites in the Women's Interagency HIV Study.

RESULTS

Albumin fell 0.44 g/L/y in 1627 women who survived and at a faster rate in 397 who died (1.54 g/L/y; p <.01). In a time-dependent model adjusting for disease markers, the relative hazard (RH) was fivefold higher in patients with serum albumin <35 g/L compared with patients with serum albumin >42 g/L. The RH of serum albumin <35 g/L in women with CD4+ lymphocyte counts > or =200 cells/micro L was 8.2 [95% CI: 4.2-15.8]) versus only 3.8 [95% CI: 2.4-6.1] in those with counts <200 cells/mm3. In a fixed-covariate Cox analysis of patients who started HAART during the study, albumin prior to HAART was associated with a higher RH (7.0 for albumin <35 g/L versus >42 g/L) than were other factors.

CONCLUSION

Serum albumin is a strong independent predictor of mortality in HIV-1-infected women after adjustment for known disease markers and may be useful for clinical monitoring.

Total energy expenditure and carbohydrate oxidation are increased in the human immunodeficiency virus lipodystrophy syndrome

To determine whether total energy expenditure (TEE) is increased in the human immunodeficiency virus (HIV) lipodystrophy syndrome, we compared energy expenditure (EE) and substrate oxidation rates in 12 HIV-infected men with lipodystrophy, 7 HIV-infected men without lipodystrophy, and 14 healthy controls. TEE and nutrient oxidation rates were assessed by whole-room indirect calorimetry. Resting energy expenditure (REE) was measured by indirect calorimetry using the open-circuit technique. Body composition was assessed by dual-energy x-ray absorptiometry (DEXA). Insulin sensitivity was measured using the insulin-modified frequently sampled intravenous glucose tolerance test. TEE adjusted for lean body mass (LBM) was significantly higher in the HIV-infected group with lipodystrophy compared to HIV-infected patients without lipodystrophy (2,873.3 +/- 69 v 2,573.9 +/- 92 kcal/d, P =.02) and compared to healthy controls (2,873.3 +/- 69 v 2,404.0 +/- 64 kcal/d, P <.001). REE and sleeping metabolic rate (SMR) adjusted for LBM were also significantly higher in the HIV-infected group with lipodystrophy compared to both HIV-infected and healthy controls. Carbohydrate oxidation rates adjusted for LBM were higher in men with HIV lipodystrophy as compared to healthy controls (362.5 +/- 23 v 250.0 +/- 22 g/d, P = <.01) and tended to be higher as compared to HIV-infected controls (362.5 +/- 23.6 v 297.3 +/- 31 g/d, P =.1). In conclusion, TEE and carbohydrate oxidation are increased in the HIV lipodystrophy syndrome. The increase in TEE appears to be due to increases in REE. The pathogenesis of elevated EE in HIV lipodystrophy and other forms of lipodystrophy remains to be determined.

Longitudinal evolution of HIV-1-associated lipodystrophy is correlated to serum cortisol:DHEA ratio and IFN-alpha

BACKGROUND

We have previously shown that lipid alterations in HIV-1-associated lipodystrophy (LD) are correlated with decreased serum dehydroepiandosterone (DHEA) and increased cortisol:DHEA ratio and IFN-alpha levels.

OBJECTIVE

To evaluate in a longitudinal study whether steroid and cytokine modifications are associated with the evolution of physical changes and lipid alterations associated with LD.

METHODS

Thirty-four HIV-1-positive men were followed during 32.5 +/- 4.0 months and tested at four time-points. The patients were subdivided into five groups according to physical changes and anthropometric measurements: LD-negative, initially LD-negative becoming LD-positive, LD-positive unchanged, aggravated or improved. Serum lipids, apolipoproteins, adrenal steroids and cytokines were measured and compared with baseline values.

RESULTS

(1) LD aggravation is associated with persistent elevated lipids, a decrease in serum DHEA, an increase in cortisol:DHEA ratio and persistent high levels of IFN-alpha. (2) LD improvement is associated with normalization of serum lipids, an increase in serum DHEA leading to normalization in cortisol:DHEA ratio, and normalization of IFN-alpha levels. (3) In LD-positive men evolution of VLDL cholesterol is negatively correlated with DHEA (r = -0.56, P < 0.01) and positively with cortisol:DHEA ratio (r = 0.62, P < 0.004) and with IFN-alpha (r = 0.57, P < 0.01). (4) The switch to LD is associated with a decrease in serum DHEA. (5) Patients who remained LD-negative maintained normal lipids, elevated cortisol and DHEA, and normal cortisol:DHEA ratio and normal levels of IFN-alpha.

CONCLUSIONS

This study indicates that cortisol:DHEA ratio and serum IFN-alpha levels are closely associated with clinical evolution and atherogenic lipid alterations in LD.