Type 1 diabetes associated with acquired generalized lipodystrophy and insulin resistance: the effect of long-term leptin therapy

CONTEXT

Acquired generalized lipodystrophy (AGL) is marked by severe insulin resistance and hypertriglyceridemia. Rarely, AGL and type 1 diabetes (T1D) coexist.

OBJECTIVE

Our objective was to describe the response to leptin therapy in patients with coexisting AGL and T1D and to document the autoimmune diseases associated with AGL.

DESIGN AND SETTING

We conducted an open-label prospective study at the Clinical Research Center of the National Institutes of Health.

PATIENTS

Participants included 50 patients with generalized or partial lipodystrophy (acquired or congenital); two patients had both AGL and T1D.

INTERVENTION

Patients were treated with 12 months of recombinant human leptin administration to achieve high-normal serum concentrations.

RESULTS

Two patients had both AGL and T1D. The first was diagnosed with T1D at age 8 yr. Beginning at age 11 yr, he developed generalized lipodystrophy, elevated transaminases, and poor glycemic control [hemoglobin A 1c (HbA 1c) 10.7%] despite markedly increased insulin requirements (3.3-5 U/kg.d). Further evaluation revealed hypoleptinemia and hypertriglyceridemia. At age 15 yr, leptin therapy was initiated, and after 1 yr, his insulin requirements fell to 1 U/kg.d, his glycemic control improved (HbA 1c 8.4%), and both his triglycerides and transaminases normalized. The second patient developed concurrent AGL and T1D at age 6 yr. Despite insulin doses of up to 32 U/kg.d, she developed poor glycemic control (HbA 1c 10.6%), hypertriglyceridemia (2984 mg/dl), elevated transaminases, and nonalcoholic steatohepatitis. At age 13 yr, leptin therapy was started, and after 1 yr, her glycemic control improved (HbA 1c 7.3%) and her insulin requirements decreased (17 U/kg.d). Her triglycerides remained elevated but were improved (441 mg/dl).

CONCLUSIONS

Long-term recombinant leptin therapy is effective in treating the insulin resistance of patients with the unusual combination of T1D and AGL.

Corticosteroid-induced lipodystrophy is associated with features of the metabolic syndrome

OBJECTIVE

Familial and HIV-associated lipodystrophies are associated with metabolic disorders and elevated blood pressure. Whether corticosteroid-induced lipodystrophy (CIL) is also associated with features of the metabolic syndrome is unknown.

METHODS

We conducted a prospective study in two French tertiary centres and enrolled all consecutive patients starting long-term (> or = 3 months), high dosage (> or = 20 mg/day) systemic corticosteroid therapy. Three investigators assessed the development of CIL from standardized head and neck photographs. Arterial blood pressure and fasting blood glucose levels were assessed at baseline and then every three months until month 12. Total, HDL- and LDL-cholesterol and triglycerides were recorded at baseline, month 3 and month 12.

RESULTS

Eighty-eight patients were enrolled (women: 75%, mean age: 57.4 +/- 17.9 yrs, mean baseline dosage of prednisolone: 56 +/- 15 mg/day). Sixty-four patients still received corticosteroids at month 12 (mean prednisolone dosage: 11 +/- 4 mg/day). In intention-to-treat analysis, the cumulative incidence rate of CIL at months 3 and 12 was 61 +/- 8% and 69 +/- 9%, respectively. Baseline characteristics were similar in patients who developed CIL and patients who did not develop CIL during follow-up except with regard to baseline body mass index, which was higher in patients who develop CIL (24.3 +/- 3.7 kg/m2 vs 21.4 +/- 3.2 kg/m2, P= 0.02). Blood pressure was significantly higher in CIL+ patients at month 9 (135/78 mmHg vs 127/73 mmHg) and month 12 (141/81 mmHg vs 128/72 mmHg) visits. Moreover, compared with CIL- patients, CIL+ patients had significantly higher plasma concentrations of fasting blood glucose, triglycerides and total cholesterol and lower HDL-cholesterol concentration during follow-up.

CONCLUSIONS

CIL is associated with features of the metabolic syndrome and should then not be considered only as an aesthetic challenge. Further studies are required to test the relation between CIL and cardiovascular events.

High doses of stavudine induce fat wasting and mild liver damage without impairing mitochondrial respiration in mice

OBJECTIVE

Stavudine (d4T), a nucleoside reverse-transcriptase inhibitor (NRTI), can induce lipoatrophy, fatty liver, hyperlactataemia and abnormal liver tests. NRTI toxicity is usually ascribed to mitochondrial DNA (mtDNA) depletion and impaired mitochondrial respiration. However, NRTIs could have effects unrelated to mtDNA. Recently, we reported that 100 mg/kg/day of d4T stimulated fatty acid oxidation (FAO) in mouse liver, and reduced body fatness without depleting white adipose tissue (WAT) mtDNA. We hypothesized that higher d4T doses could further reduce adiposity, while inhibiting hepatic FAO.

METHODS

Mice were treated for 2 weeks with d4T (500 mg/kg/day), L-carnitine (200 mg/kg/day) or both drugs concomitantly. Body fatness was assessed by dual energy X-ray absorptiometry, and investigations were performed in plasma, liver, muscle and WAT.

RESULTS

D4T reduced the gain of body adiposity, WAT leptin, whole body FAO and plasma ketone bodies, and increased liver triglycerides and plasma aminotransferases with mild ultrastructural abnormalities in hepatocytes. Plasma lactate and respiratory chain activities in tissues were unchanged. Stearoyl-CoA desaturase (SCD-1), an enzyme negatively regulated by leptin, was overexpressed in liver. High doses of beta-aminoisobutyric acid (BAIBA), a d4T catabolite, increased plasma ketone bodies. Although L-carnitine did not correct body adiposity, it prevented d4T-induced impairment of FAO and liver abnormalities.

CONCLUSIONS

D4T overdosage triggers fat wasting, leptin insufficiency and mild liver damage, without causing respiratory chain dysfunction. Overexpression of SCD-1 reduces fatty acid oxidation and overcomes the stimulating effect of BAIBA on hepatic FAO. L-carnitine does not correct leptin insufficiency but prevents d4T-induced impairment of FAO and liver damage.

Effects of protease inhibitors on glucose tolerance, lipid metabolism, and body composition in children and adolescents infected with human immunodeficiency virus

OBJECTIVE

To evaluate the effects of protease inhibitors (PIs) as antiretroviral therapy in comparison with other antiretroviral (non-PI) medications on glucose tolerance, lipid metabolism, and body fat distribution in human immunodeficiency virus (HIV)-infected young patients.

METHODS

We conducted a cross-sectional clinical study in an outpatient HIV clinic. The study population consisted of 21 patients (15 female and 6 male) who had had at least 6 months of antiretroviral treatment. The mean age of the patients was 11.9 years (range, 6 to 16.5).

RESULTS

Fifteen patients treated with PIs and 6 patients treated with non-PIs were enrolled in the study. We found no significant differences in the lipid panel and insulin resistance, as determined by using the Quantitative Insulin Sensitivity Check Index formula, in the PI group in comparison with the non-PI group. Lipodystrophy was observed in 47% (7 of 15) of the PI group and 33% (2 of 6) of the non-PI group (P = 0.66). In the presence of lipodystrophy, serum triglyceride levels were higher in the PI group than in the non-PI group (P = 0.046). No such difference was found between the treatment groups when no lipodystrophy was present. There was no significant difference in insulin resistance between the treatment groups in the presence or absence of lipodystrophy.

CONCLUSION

Our study found the presence of lipodystrophy in HIV-infected young patients regardless of whether they were taking PIs or not. In the patients who had lipodystrophy, those treated with PIs had higher serum triglyceride levels than those not treated with PIs.

Clinical evidence that hyperinsulinaemia independent of gonadotropins stimulates ovarian growth

OBJECTIVE

Ovarian enlargement is a constant feature of syndromes of extreme insulin resistance. The objective of this study is to show the role of insulin on ovarian growth in the presence of low gonadotropin levels.

PATIENTS

Seven young patients with syndromes of extreme insulin resistance (five with lipodystrophy, one with Type B syndrome and one with Rabson-Mendenhall syndrome) were studied.

MEASUREMENTS

Baseline LH concentrations and luteinizing hormone releasing hormone (LHRH) tests were performed. Total testosterone, insulin and C-peptide values were measured. Pelvic ultrasounds were performed.

RESULTS

Four patients were prepubertal (age range 7-10 years old) and had prepubertal gonadotropin levels, and 2 of the 4 who were tested did not respond to LHRH (NIH 10 and RM-PAL). Three patients were Tanner stage 4 (age range 13-17 years old) and had low gonadotropins that did not respond to LHRH stimulation test. All seven patients had marked hyperinsulinaemia and 6 of 7 had at least one enlarged ovary. Testosterone values were increased in 4 of 7 patients.

CONCLUSION

This represents the first example of the pathologic role of insulin to stimulate ovarian growth with low circulating gonadotropins. Thus, while ovarian growth and steroidogenesis are normally stimulated by gonadotropins at puberty, hyperinsulinaemia stimulates pathologic growth of the ovary and an androgenic steroid profile that is active at all ages. We suggest that these patients constitute a model to separate the effect of insulin from gonadotropin in stimulating ovarian growth and/or steroidogenesis.

Long-term efficacy of leptin replacement in patients with generalized lipodystrophy

Ectopic fat accumulation has been implicated as a contributing factor in the abnormal metabolic state of obesity. One human model of ectopic fat deposition is generalized lipodystrophy. Generalized lipodystrophy is a rare disorder characterized by a profound deficiency of adipose tissue with resultant loss of triglyceride storage capacity and reduced adipokines, including leptin. Subjects with generalized lipodystrophy and reduced leptin levels often have an increased appetite leading to hyperphagia. Excess fuel consumption, coupled with a lack of adipose tissue, contributes to the significant ectopic triglyceride accumulation in the muscle and liver seen in these subjects. This ectopic fat, along with the deficiency in leptin signaling and perhaps other adipokines, likely contributes to insulin resistance, diabetes, and hepatic steatosis. We report here the long-term effects of leptin replacement in a cohort of these subjects. Fifteen patients with generalized lipodystrophy were treated with twice-daily recombinant methionyl human leptin (r-metHuLeptin) for 12 months. We evaluated metabolic parameters at baseline and every 4 months. Antidiabetes medications were decreased or discontinued as necessary. Reductions were seen in serum fasting glucose (from 205 +/- 19 to 126 +/- 11 mg/dl; P < 0.001), HbA1c (from 9 +/- 0.4 to 7.1 +/- 0.5%; P < 0.001), triglycerides (from 1,380 +/- 500 to 516 +/- 236 mg/dl; P < 0.001), LDL (from 139 +/- 16 to 85 +/- 7 mg/dl; P < 0.01), and total cholesterol (from 284 +/- 40 to 167 +/- 21 mg/dl; P < 0.01). HDL was unchanged (from 31 +/- 3 to 29 +/- 2 mg/dl; P = 0.9). Liver volumes were significantly reduced (from 3,663 +/- 326 to 2,190 +/- 159 cm3; P < 0.001), representing loss of steatosis. Decreases were seen in total body weight (from 61.8 +/- 3.6 to 57.4 +/- 3.4 kg; P = 0.02) and resting energy expenditure (from 1,929 +/- 86 to 1,611 +/- 101 kcal/24 h; P < 0.001). R-metHuLeptin led to significant and sustained improvements in glycemia, dyslipidemia, and hepatic steatosis. Leptin represents the first novel, effective, long-term treatment for severe forms of lipodystrophy.

Metabolic benefits 24 months after replacing a protease inhibitor with abacavir, efavirenz or nevirapine

OBJECTIVE

To evaluate the 24-month metabolic and morphological benefits obtained from replacing the protease inhibitor (PI) in a regimen with nevirapine, efavirenz or abacavir.

DESIGN AND METHODS

NEFA was a randomized study designed to compare the efficacy of nevirapine, efavirenz or abacavir as substitutes for PI. A subset of 90 patients [abacavir (n = 29), efavirenz (n = 32), nevirapine (n = 29)] formed the metabolic study. Fasting total cholesterol (TC), high density lipoprotein cholesterol (HDL-c) and triglycerides levels were determined. Glucose homeostasis parameters were also collected. Lipodystrophy was evaluated by clinical examination and morphological measurements.

RESULTS

Treatment simplification led to overall lipid profile improvements. At 24 months, the two non-nucleoside reverse transcriptase inhibitors produced similar lipid benefits: HDL-c levels increased [efavirenz, 15% (P = 0.001); nevirapine, 21% (P < 0.001)] and TC to HDL-c ratios decreased [efavirenz, 14% (P < 0.001); nevirapine, 19% (P < 0.01)], an effect not observed in the abacavir arm. Non-HDL-c levels decreased by 10% in both the abacavir (P = 0.001) and efavirenz (P < 0.05) arms. Significant decreases in the levels of triglycerides occurred for the first year in all treatments; however, at 24 months most of the initial loss had been regained. Patients with baseline moderate or severe lipodystrophy obtained less-pronounced lipid benefits. Several insulin resistance markers showed a trend towards improvement. Conversely, no improvements in morphological abnormalities were observed.

CONCLUSIONS

Replacing PI with efavirenz, nevirapine or abacavir improved the lipid profile, with more marked results in non-lipodystrophic patients. In contrast, this strategy does not seem to be effective for reversing body fat abnormalities.

Leptin reverses nonalcoholic steatohepatitis in patients with severe lipodystrophy

Severe lipodystrophy is characterized by diminished adipose tissue and hypoleptinemia, leading to ectopic triglyceride accumulation. In the liver, this is associated with steatosis, potentially leading to nonalcoholic steatohepatitis (NASH). We investigated the prevalence of NASH and the effect of leptin replacement in these patients. Ten patients with either generalized lipodystrophy (8 patients) or Dunnigan's partial lipodystrophy (2 patients) were included in this analysis. Paired liver biopsy specimens were obtained at baseline and after treatment with recombinant methionyl human leptin (r-metHuLeptin), mean duration 6.6 months. The extents of portal and parenchymal inflammation, steatosis, ballooning, presence of Mallory bodies, and fibrosis in liver biopsy specimens were scored using a previously validated system developed to assess NASH activity. Histological disease activity was defined as the sum of ballooning, steatosis, and parenchymal inflammation scores. We concurrently tested serum triglycerides and aminotransferases and estimations of liver volume and fat content by magnetic resonance imaging. Eight of 10 patients met histological criteria for NASH at baseline. After treatment with r-metHuLeptin, repeat histological examinations showed significant improvements in steatosis (P = .006) and ballooning injury (P = .005), with a reduction of mean NASH activity by 60% (P = .002). Fibrosis was unchanged. Significant reductions were seen in mean serum triglycerides (1206-->226 mg/dL, P = .002), glucose (220-->144 mg/dL, P = .02), insulin (46.4-->24.8 muIU/mL, P = .004), ALT (54-->24 U/L, P = .02), AST (47-->22 U/L, P = .046), liver volume (3209-->2391 cm(3), P = .007), and liver fat content (31-->11%, P = .006). In conclusion, r-metHuLeptin therapy significantly reduced triglycerides, transaminases, hepatomegaly, and liver fat content. These reductions were associated with significant reductions in steatosis and the hepatocellular ballooning injury seen in NASH.

The long-term effect of recombinant methionyl human leptin therapy on hyperandrogenism and menstrual function in female and pituitary function in male and female hypoleptinemic lipodystrophic patients

Lipodystrophy patients are hypoleptinemic and insulin resistant. Women have enlarged polycystic ovaries, hyperandrogenism, and amenorrhea. We have determined the role of correction of hypoleptinemia on these metabolic and neuroendocrine parameters. Ten females and 4 males with generalized lipodystrophy were treated with recombinant methionyl human leptin (r-metHuLeptin) in physiologic doses in an open-labeled study for a period of 12 and 8 months, respectively. In the female group, serum free testosterone decreased from 39.6 +/- 11 to 18.9 +/- 4.5 ng/dL (P < 0.01) and serum sex hormone binding globulin increased from 14 +/- 2.5 to 25 +/- 4.8 nmol/L (P < 0.02). Luteinizing hormone (LH) responses to LH releasing hormone were more robust after therapy and significantly changed in the youngest group of 3 female patients (P < 0.01). Ovarian ultrasound showed a polycystic ovarian disease pattern in all patients and did not change after therapy. Eight of the 10 patients had amenorrhea prior to therapy and all 8 developed normal menses after therapy. In the male group, serum testosterone tended to increase from 433 +/- 110 to 725 +/- 184 ng/dL (P = 0.1) and sex hormone binding globulin also increased from 18.25 +/- 2.6 to 27 +/- 1.7 nmol/L (P < 0.04) following r-metHuLeptin therapy. Serum LH response to LH releasing hormone did not show significant changes. Five additional hypoleptinemic male subjects with minimal metabolic abnormalities underwent normal pubertal development without receiving r-metHuLeptin therapy. In both genders, insulin-like growth factor increased significantly and there were no differences in growth hormone, thyroid, or adrenal hormone levels following r-metHuLeptin therapy. Glycemic parameters significantly improved after r-metHuLeptin therapy in both groups. Hypoglycemic medications were discontinued in 7 of 12 patients and dramatically reduced in 5 patients. r-metHuLeptin therapy plays an important role in insulin sensitivity. In females, it plays an additional role in normalizing menstrual function. This is likely to occur both from increasing insulin sensitivity and from restoring LH pulsatility. The persistent hypoleptinemic state in these subjects did not inhibit pubertal development.

Short communication: benefits in the lipid profile after substitution of abacavir for Stavudine: a 48-week prospective study

Stavudine (d4T) has been associated with lipoatrophy and hyperlactatemia. In recent studies, d4T has also been related to both hypercholesterolemia and hypertriglyceridemia. Replacing d4T with another nucleoside analogue such as abacavir (ABC) may reduce lactate levels and improve lipoatrophy in the long term. However, the impact of this strategy on the lipid profile is still unclear. In a prospective and randomized study, fasting lipids were examined over 48 weeks in 112 subjects on d4T regimens, 49 of whom replaced d4T with ABC. The substitution of ABC for d4T was found to be safe and provided a reduction in both LDL cholesterol and the total cholesterol (TC)/HDLc ratio, which might impact favorably on cardiovascular risk.

Insulin-like growth factors, insulin-like growth factor-binding proteins, insulin-like growth factor-binding protein-3 protease, and growth hormone-binding protein in lipodystrophic human immunodeficiency virus-infected patients

Human immunodeficiency virus (HIV)-lipodystrophy is associated with impaired growth hormone (GH) secretion. It remains to be elucidated whether insulin-like growth factors (IGFs), IGF-binding proteins (IGFBPs), IGFBP-3 protease, and GH-binding protein (GHBP) are abnormal in HIV-lipodystrophy. These parameters were measured in overnight fasting serum samples from 16 Caucasian males with HIV-lipodystrophy (LIPO) and 15 Caucasian HIV-infected males without lipodystrophy (NONLIPO) matched for age, weight, duration of HIV infection, and antiretroviral therapy. In LIPO, abdominal fat mass and insulin concentration were increased (>90%, P < .01) and insulin sensitivity (Log10ISI(composite)) was decreased (-50%, P < .001). Total and free IGF-I, IGF-II, IGFBP-3, and IGFBP-3 protease were similar between groups (all P > .5), whereas, in LIPO, IGFBP-1 and IGFBP-2 were reduced (-36%, P < .05 and -50%, P < .01). In pooled groups, total IGF-I, free IGF-I, total IGF-II, and IGFBP-3, respectively, correlated inversely with age (all P < .01). In pooled groups, IGFBP-1 and IGFBP-2 correlated positively with insulin sensitivity (age-adjusted all P < .05). IGFBP-3 protease correlated with free IGF-I in pooled groups (r(p) = 0.47, P < .02), and in LIPO (r(p) = 0.71, P < .007) controlling for age, total IGF-I, and IGFBP-3. GHBP was increased, whereas GH was decreased in LIPO (all P < .05). GH correlated inversely with GHBP in pooled groups (P < .05). Taken together the similar IGFs and IGFBP-3 concentrations between study groups, including suppressed GH, and increased GHBP in LIPO, argue against GH resistance of GH-sensitive tissues in LIPO compared with NONLIPO; however, this notion awaits examination in dose-response studies. Furthermore, our data suggest that IGFBP-3 protease is a significant regulator of bioactive IGF-I in HIV-lipodystrophy.

[Outcome of hyperlactatemia and lipodystrophy syndromes in patients infected with human immunodeficiency virus]

HIV-positive persons requiring a highly active antiretroviral therapy containing one or more nucleosidic reverse transcriptase inhibitors associated with or without protease inhibitors are exposed to metabolic side effects among which lipodystrophy and hyperlactemia, defined by blood lactates higher than 2,25 mmol/L. Hyperlactatemia had to be differentiated from lactic acidosis of type B (without hypoxemia, lactates higher than 5 mmol/L and arterial pH lower than 7,3), a rare but potentially fatal complication by multi-visceral failure. The accused INRT induce mitochondrial toxicity by inhibition of DNA gamma polymerase and deterioration of its DNA. Our exploratory study, troop of 282 patients, identified age and stavudine like statistically associated, which has occurred of this metabolic anomaly. The patients having profited of a therapeutic change with the profit from drugs minus hyperlactatogenic presented an obvious clinical and biological improvement; whereas similar switch of therapy occurred for the lipodystrophic patients presented any clinical improvement. Nevertheless, biological parameters (blood lactates, triglycerides, total cholesterol and LDL-cholesterol) were significantly decreased after this therapeutic switch occurred on the lipodystrophic patients. In conclusion, the measurement of the following biological parameters: glycemia, lactatemia, triglycerides, total cholesterol and LDL-cholesterol at patient VIH, in a simple and rigorous pre-analytical and analytical context, appears to us justified in the monitoring of metabolic disorders in treated HIV patients by INRT and/or IP.

Changes in body composition in patients with severe lipodystrophy after leptin replacement therapy

Leptin, an adipocyte hormone, when replaced in patients with lipodystrophy, improves insulin resistance, hyperglycemia, dyslipidemia, and hepatic steatosis. Changes in body composition accompany this metabolic improvement. We studied 14 patients (3 men and 11 women); 12 of who had generalized lipodystrophy (7 congenital, 5 acquired), and 2 patients had partial lipodystrophy. Body composition and related parameters were evaluated at baseline and after 4 and 12 months of leptin therapy. Baseline body mass index (BMI) was 21.7 +/- 0.8 kg/m(2), the percent body fat was 9.5% +/- 1.6%, and the serum leptin level was 1.7 +/- 0.3 ng/mL. On treatment, serum leptin levels increased by 10-fold. All patients reported a decrease in appetite on therapy. After 4 months, both daily caloric intake and resting energy expenditure (REE) decreased. The liver volume decreased (baseline = 3,055 +/- 281 cm(3); 4 months = 2,433 +/- 243 cm(3), P =.006). Dual energy x-ray absorptiometry (DEXA) demonstrated significant decreases in fat mass (5.4 +/- 0.8 kg to 5.0 +/- 0.8 kg; P =.003) and lean body mass (51.2 +/- 3.2 kg to 48.3 +/- 3.4 kg; P =.003) at 4 months on therapy. There was no impact of leptin therapy on bone mineral content, mineral density, and metabolism. Changes in body composition occurred during the first 4 months of leptin therapy, but then stabilized and were sustained thereafter.

Insulin resistance and diabetes

Metabolic complications associated with HIV disease and its treatment--including insulin resistance and diabetes, abnormal cholesterol and triglyceride levels (dyslipidemia), and body fat gain or loss--remain a medical mystery and a topic of intense interest for AIDS researchers and people with HIV alike. While these complications sometimes have been collectively referred to as "lipodystrophy syndrome," it remains unclear whether or how they are related and what causes them. Scientists are urgently trying to better understand these conditions, which may have a negative impact on quality of life, interfere with adherence to antiretroviral therapy, and lead to long-term health problems. High blood glucose levels (hyperglycemia) and dyslipidemia are a particular concern because in the population at large they have been linked with increased risk of heart disease. Much research is underway and new clues are steadily emerging, but Daniel Kuritzkes, MD, of Boston's Brigham and Women's Hospital predicts, "We'll need several more years of follow-up to get a better perspective."

Cardiovascular complications and increased levels of circulating modified low density lipoprotein in HIV patients and patients with lipodystrophy

The introduction of highly active antiretroviral therapy (HAART) for patients infected with HIV has significantly prolonged the life expectancy and to some extent has restored a functional immune response. However, the premature introduction of HAART has led to a significant and alarming increase in cardiovascular complications, including myocardial infarction and the appearance of abnormal distribution of body fat seen as lipodystrophy. One key element in the development of ischemic coronary artery disease is the presence of circulating and tissue-fixed modified low density lipoprotein (mLDL) that contributes to the initiation and progression of arterial lesions and to the formation of foam cells. Even though not completely elucidated, the most likely mechanism involves mLDL in the inflammatory response and the induction of a specific immune response against mLDL. Circulating antibodies against mLDL can serve as an indirect marker of the presence of circulating and vessel-fixed mLDL. In the present study, we measured antibodies to mLDL and correlated them with immune status (i.e., number of CD4+ T cells) in 59 HIV patients and with the clinical manifestation of lipodystrophy in 10 patients. We observed a significant reduction in anti-mLDL antibody levels related both to lipodystrophy and to an immunocompromised state in HIV patients. We speculate that these antibodies may explain in part the rapid development of ischemic coronary artery disease in some patients.

Regulation of plasma PAI-1 concentrations in HAART-associated lipodystrophy during rosiglitazone therapy

OBJECTIVE

Patients with highly active antiretroviral therapy-associated lipodystrophy (HAART+LD+) have high plasminogen activator inhibitor-1 (PAI-1) concentrations for unknown reasons. We determined whether (1). plasma PAI-1 antigen concentrations are related to liver fat content (LFAT) independently of the size of other fat depots and (2) rosiglitazone decreases PAI-1 and LFAT in these patients.

METHODS AND RESULTS

In the cross-sectional study, 3 groups were investigated: 30 HIV-positive patients with HAART+LD+, 13 HIV-positive patients without lipodystrophy (HAART+LD-), and 15 HIV-negative subjects (HIV-). In the treatment study, the HAART+LD+ group received either rosiglitazone (8 mg, n=15) or placebo (n=15) for 24 weeks. Plasma PAI-1 was increased in HAART+LD+ (28+/-2 ng/mL) compared with the HAART+LD- (18+/-3, P<0.02) and HIV- (10+/-3, P<0.001) groups. LFAT was higher in HAART+LD+ (7.6+/-1.7%) than in the HAART+LD- (2.1+/-1.1%, P<0.001) and HIV- (3.6+/-1.2%, P<0.05) groups. Within the HAART+LD+ group, plasma PAI-1 was correlated with LFAT (r=0.49, P<0.01) but not with subcutaneous or intra-abdominal fat or serum insulin or triglycerides. In subcutaneous adipose tissue, PAI-1 mRNA was 2- to 3-fold higher in the HAART+LD+ group than in either the HAART+LD- or HIV- group. Rosiglitazone decreased LFAT, serum insulin, and plasma PAI-1 and increased serum triglycerides but had no effect on intra-abdominal or subcutaneous fat mass or PAI-1 mRNA.

CONCLUSIONS

Plasma PAI-1 concentrations are increased in direct proportion to LFAT in HAART+LD+ patients. Rosiglitazone decreases LFAT, serum insulin, and plasma PAI-1 without changing the size of other fat depots or PAI-1 mRNA in subcutaneous fat. These data suggest that liver fat contributes to plasma PAI-1 concentrations in these patients.

Inhibition of lipolysis improves insulin sensitivity in protease inhibitor-treated HIV-infected men with fat redistribution

BACKGROUND

Fatty acid concentrations are increased in patients with HIV and fat redistribution and may contribute to insulin resistance in this population.

OBJECTIVE

We determined the effects of acute inhibition of lipolysis on insulin sensitivity in HIV-infected patients with fat redistribution who were receiving a protease inhibitor.

DESIGN

Seven HIV-infected men [age: 45 +/- 2 y; body mass index (in kg/m(2)): 28.8 +/- 1.9] with a fasting insulin concentration > or= 104 pmol/L (15 micro IU/mL), combined visceral adiposity and peripheral lipoatrophy, and receiving a protease inhibitor were studied. Tolbutamide-modified frequently sampled intravenous-glucose-tolerance tests (FSIGTTs) were performed after randomized double-blind administration of acipimox (500 mg at -90 and 0 min), a potent inhibitor of lipolysis, and placebo. The subjects completed 2 FSIGTTs separated by 3-7 d.

RESULTS

At baseline, fasting insulin and fatty acid concentrations were 27.6 +/- 5.0 micro IU/mL and 0.83 +/- 0.08 mmol/L (normal range: 0.1-0.6 mmol/L), respectively. Fatty acid concentrations were significantly reduced after acipimox compared with placebo (fatty acid area under the curve: acipimox = 73 +/- 8 compared with placebo = 122 +/- 12 mmol x 270 min/L, P = 0.002). Acipimox treatment resulted in a significant increase in the insulin sensitivity index (acipimox = 1.63 +/- 0.5 compared with placebo = 0.88 +/- 0.3 x 10(-4) x min(-1) x micro IU/mL, P = 0.015).

CONCLUSIONS

Acute inhibition of lipolysis and reduction in fatty acid concentrations are associated with improved insulin sensitivity in patients with HIV lipodystrophy and hyperinsulinemia. Further studies are needed to determine whether long-term antilipolytic strategies to reduce fatty acid concentrations may be useful in treating the metabolic disturbances associated with HIV lipodystrophy.

Elevated serum C-reactive protein and free fatty acids among nondiabetic carriers of missense mutations in the gene encoding lamin A/C (LMNA) with partial lipodystrophy

OBJECTIVE

Dunnigan-type familial partial lipodystrophy (FPLD) due to mutant LMNA is a monogenic form of insulin resistance. Affected subjects, especially women, are at increased risk of early coronary heart disease (CHD). Although common insulin resistance is associated with several biochemical perturbations, including elevated C-reactive protein (CRP), the biochemical profile in subjects with mutant LMNA is incompletely defined.

METHODS AND RESULTS

We studied 35 nondiabetic adult FPLD subjects (of whom 24 were women) with either the LMNA R482Q or R482W missense mutations and 51 matched normal first-degree relatives (of whom 27 were women). Compared with normal controls, LMNA mutation carriers had significantly higher plasma insulin and more dyslipidemia, higher mean triglycerides and lower HDL cholesterol, significantly higher nonesterified free fatty acids and CRP, and significantly lower leptin and adiponectin than controls. Subgroup analyses showed that these differences were more pronounced in women. Other biomarkers such as resistin, fibrinogen, and plasminogen activator inhibitor-1 were not different between groups.

CONCLUSIONS

LMNA mutations in nondiabetic patients with FPLD are associated with several metabolic and biochemical changes, particularly in women. The unfavorable profile might contribute to the increased susceptibility to CHD seen in LMNA mutation carriers.

Reduction of fat accumulation and lipid disorders by individualized light aerobic training in human immunodeficiency virus infected patients with lipodystrophy and/or dyslipidemia

BACKGROUND

The management of abdominal fat accumulation and metabolic disorders in HIV1-infected patients, by an aerobic training program, is considered.

METHODS

Seventeen lipodystrophic and 2 dyslipidemic (without body modification) adults were studied before and after 4 months of training. The training load was individualized on a ventilatory threshold basis, determined during a maximal exercise test on cycle ergometer. Total (TAT), Visceral (VAT) and Subcutaneous Adipose Tissue (SAT) were assessed by CT-scan. Total (TC) and High Density Lipoprotein (HDL-C) Cholesterol, Triglycerides (TG), lactate (La), insulin and glucose were measured after a 12-hour-overnight fast. LDL, TC/HDL, TG/HDL, HOMA-insulin resistance index and coronary heart disease (CHD) relative risk (RR(CHD)) were calculated.

RESULTS

Besides a significant improvement of aerobic fitness, trained patients exhibited a reduction in TAT (-12.8%, p < 0.001), specially at the visceral level (- 12%, p < 0.01) and in TC, TG and La (- 23%, - 43% and - 19% respectively, p < 0.01). HDL-C was increased (+ 6%, p < 0.01). All these effects were above changes that could be expected by a possible regression to the mean artefact. Both TC/HDL and TG/HDL were reduced (p < 0.01) and the estimated RR(CHD) decreased by approximately 13% (p < 0.01). No significant training effect was observed on the 9 available HOMAs. Significant correlations were found between changes in blood lipid values and baseline measures (r range - 0.55 to - 0.79, p < 0.05), indicating a larger improvement when baseline lipid parameters were higher.

CONCLUSION

Aerobic training reduced visceral fat, lipid disorders, basal blood lactate and CHD markers in HIV patients. Training effects were particularly important for patients with marked dyslipidemia.

Antiretroviral treatment patterns and incident HIV-associated morphologic and lipid abnormalities in a population-based chort

This study provides population-based estimates of the incidence of constituent symptoms associated with HIV-related lipodystrophy syndrome. Possible predictors of symptomatology based on analysis of accrued cases are provided after adjustment for a broad range of personal, clinical, and treatment characteristics. Patients enrolled in a province-wide HIV/AIDS treatment program reported annually on the occurrence of lipoatrophy, lipohypertrophy, and elevated triglyceride and cholesterol levels. Of 1261 individuals who provided baseline data, 745 were available at follow-up, among whom incidence was 27% for lipoatrophy, 21% for lipohypertrophy, and 10% and 16% for increased triglyceride and cholesterol levels, respectively. In logistic multivariate modeling, incident lipoatrophy was associated with duration of stavudine (per quarter) (adjusted odds ratio [AOR] 1.18; 95% confidence interval [CI] 1.09-1.27) and having been diagnosed with AIDS (AOR 2.07; 95% CI 1.20-3.56). Lipohypertrophy risk increased with use of protease inhibitor (AOR 3.53; 95% CI 1.81-6.86) and stavudine (AOR 3.67; 95% CI 1.61-8.38). Incident cholesterol or triglyceride abnormalities were associated with protease inhibitor use (AOR 7.17; 95% CI 2.46-20.96) and duration of ritonavir (per quarter) (AOR 1.12; 95% CI 1.04-1.21). Our findings suggest high annual rates of incidence and a role of first line antiretroviral therapies in symptom development. These outcomes, in conjunction with the findings of others have important implications for evolving treatment patterns.