Identification of novel genetic variations in ABCB6 and GRN genes associated with HIV-associated lipodystrophy

Protease inhibitors (PIs) are associated with an incidence of lipodystrophy among people living with HIV(PLHIV). Lipodystrophiesare characterised by the loss of adipose tissue. Evidence suggests that a patient's lipodystrophy phenotype is influenced by genetic mutation, age, gender, and environmental and genetic factors, such as single-nucleotide variants (SNVs). Pathogenic variants are considered to cause a more significant loss of adipose tissue compared to non-pathogenic. Lipid metabolising enzymes and transporter genes have a role in regulating lipoprotein metabolism and have been associated with lipodystrophy in HIV-infected patients (LDHIV). The long-term effect of the lipodystrophy syndrome is related to cardiovascular diseases (CVDs). Hence, we determined the SNVs of lipid metabolising enzymes and transporter genes in a total of 48 patient samples, of which 24 were with and 24 were without HIV-associated lipodystrophy (HIVLD) using next-generation sequencing. A panel of lipid metabolism, transport and elimination genes were sequenced. Three novel heterozygous non-synonymous variants at exon 8 (c.C1400A:p.S467Y, c.G1385A:p.G462E, and c.T1339C:p.S447P) in the ABCB6 gene were identified in patients with lipodystrophy. One homozygous non-synonymous SNV (exon5:c.T358C:p.S120P) in the GRN gene was identified in patients with lipodystrophy. One novelstop-gain SNV (exon5:c.C373T:p.Q125X) was found in the GRN gene among patients without lipodystrophy. Patients without lipodystrophy had one homozygous non-synonymous SNV (exon9:c.G1462T:p.G488C) in the ABCB6 gene. Our findings suggest that novel heterozygous non-synonymous variants in the ABCB6 gene may contribute to defective protein production, potentially intensifying the severity of lipodystrophy. Additionally, identifying a stop-gain SNV in the GRN gene among patients without lipodystrophy implies a potential role in the development of HIVLD.

Maternal smoking, nutritional factors at different life stage, and the risk of incident type 2 diabetes: a prospective study of the UK Biobank

BACKGROUND

This study aims to investigate potential interactions between maternal smoking around birth (MSAB) and type 2 diabetes (T2D) pathway-specific genetic risks in relation to the development of T2D in offspring. Additionally, it seeks to determine whether and how nutritional factors during different life stages may modify the association between MSAB and risk of T2D.

METHODS

This study included 460,234 participants aged 40 to 69 years, who were initially free of T2D from the UK Biobank. MSAB and breastfeeding were collected by questionnaire. The Alternative health eating index(AHEI) and dietary inflammation index(DII) were calculated. The polygenic risk scores(PRS) of T2D and pathway-specific were established, including β-cell function, proinsulin, obesity, lipodystrophy, liver function and glycated haemoglobin(HbA1c). Cox proportion hazards models were performed to evaluate the gene/diet-MSAB interaction on T2D. The relative excess risk due to additive interaction (RERI) were calculated.

RESULTS

During a median follow-up period of 12.7 years, we identified 27,342 cases of incident T2D. After adjustment for potential confounders, participants exposed to MSAB had an increased risk of T2D (HR=1.11, 95%CI:1.08-1.14), and this association remained significant among the participants with breastfeeding (HR= HR=1.10, 95%CI: 1.06-1.14). Moreover, among the participants in the highest quartile of AHEI or in the lowest quartile of DII, the association between MSAB and the increased risk of T2D become non-significant (HR=0.94, 95%CI: 0.79-1.13 for AHEI; HR=1.09, 95%CI:0.99-1.20 for DII). Additionally, the association between MSAB and risk of T2D became non-significant among the participants with lower genetic risk of lipodystrophy (HR=1.06, 95%CI:0.99-1.14), and exposed to MSAB with a higher genetic risk for β-cell dysfunction or lipodystrophy additively elevated the risk of T2D(RERI=0.18, 95%CI:0.06-0.30 for β-cell function; RERI=0.16, 95%CI:0.04-0.28 for lipodystrophy).

CONCLUSIONS

This study indicates that maintaining a high dietary quality or lower dietary inflammation in diet may reduce the risk of T2D associated with MSAB, and the combination of higher genetic risk of β-cell dysfunction or lipodystrophy and MSAB significantly elevate the risk of T2D in offspring.

Lipodystrophic gene Agpat2 deficiency aggravates hyperlipidemia and atherosclerosis in Ldlr-/- mice

AIMS

Dysfunction of adipose tissue increases the risk of cardiovascular disease. It was well established that obesity aggravates atherosclerosis, but the effect of adipose tissue loss on atherosclerosis has been less studied. AGPAT2 is the first causative gene of congenital generalized lipodystrophy (CGL), but the role of AGPAT2 on atherosclerosis has not been reported. Hypertriglyceridemia is one of the clinical manifestations of CGL patients, but it is usually absent in CGL mouse model on a normal diet. This study will investigate the effect of Agpat2 on hyperlipidemia and atherosclerosis.

METHODS AND RESULTS

In this study, Agpat2 knockout (Agpat2-/-) mice were generated using CRISPR/Cas system, which showed severe loss of adipose tissue and fatty liver, consistent with previous reports. Agpat2-/- mice were then crossed with hypercholesterolemic and atherosclerotic prone LDL receptor knockout (Ldlr-/-) mice to obtain double knockout mouse model (Agpat2-/-Ldlr-/-). Plasma lipid profile, insulin resistance, fatty liver, and atherosclerotic lesions were observed after 12 weeks of the atherogenic high-fat diet (HFD) feeding. We found that compared with Ldlr-/- mice, Agpat2-/-Ldlr-/- mice showed significantly higher plasma total cholesterol and triglycerides after HFD feeding. Agpat2-/-Ldlr-/- mice also developed hyperglycemia and hyperinsulinemia, with increased pancreatic islet area. The liver weight of Agpat2-/-Ldlr-/- mice was about 4 times higher than that of Ldlr-/- mice. The liver lipid deposition was severe and Sirius red staining showed liver fibrosis. In addition, in Agpat2-/-Ldlr-/- mice, the area of atherosclerotic lesions in aortic arch and aortic root was significantly increased.

CONCLUSIONS

Our results show that Agpat2 deficiency led to more severe hyperlipidemia, liver fibrosis and aggravation of atherosclerosis in Ldlr-/- mice. This study provided additional insights into the role of adipose tissue in hyperlipidemia and atherosclerosis.

Prevalence and risk factors of metabolic syndrome in Ethiopia: describing an emerging outbreak in HIV clinics of the sub-Saharan Africa - a cross-sectional study

OBJECTIVES

HIV-induced chronic inflammation, immune activation and combination antiretroviral therapy (cART) are linked with adverse metabolic changes known to cause cardiovascular adversities. This study evaluates the prevalence of lipodystrophy, and metabolic syndrome (MetS), and analyses risk factors in HIV-infected Ethiopians taking cART.

METHODS

A multicentre cross-sectional study was conducted at tertiary-level hospitals. Eligible participants attending the HIV clinics were enrolled. Sociodemographic, anthropometric, clinical, HIV treatment variables, lipid profile, fasting blood glucose level, risk factors and components of MetS, also lipodystrophy, were studied. Data were analysed by SPSS statistical package V.25 with descriptive and analytical statistics. For multivariable analysis of risk factors, a logistic regression model was used. Results were presented in frequency and percentages, mean±SD, or median+IQR. Statistical significance was taken as p<0.05.

RESULTS

Among 518 studied participants, two-thirds were females, and the mean age of the study population was 45 years (SD=11). The mean duration of cART was 10 years (SD=4). Median CD4 count was 460 cells/mm3. The prevalence of MetS according to the Adult Treatment Panel III (2005) criteria was 37.6%. In multivariable analysis, independent risk factors for MetS were age >45 years (aHR 1.8, 95% CI 1.2 to 2.4), female sex (aHR 1.8, 95% CI 1.1 to 2.8), body mass index (BMI)>25 kg/m2 (aHR 2.7, 95% CI 1.8 to 4.1), efavirenz-based cART (aHR 2.8, 95% CI 1.6 to 4.8) and lopinavir/ritonavir-based cART (aHR 3.7, 95% CI 1.0 to 13.3). The prevalence of lipodystrophy was 23.6%. Prior exposure to a stavudine-containing regimen was independently associated with lipodystrophy (aHR 3.1, 95% CI 1.6 to 6.1).

CONCLUSION

Our study revealed 38% of the participants had MetS indicating considerable cardiovascular disease (CVD) risks. Independent risk factors for MetS were BMI≥25 kg/m2, efavirenz and lopinavir/ritonavir-based cART, female sex and age ≥45 years. In addition to prevention, CVD risk stratification and management will reduce morbidity and mortality in people with HIV infection.

Juvenile dermatomyositis: association between nail fold capillary end row loop- area under the curve- and disease damage indicators

BACKGROUND

Juvenile Dermatomyositis (JDM) is a rare autoimmune disease characterized by skin and muscle inflammation. The loss of nail fold capillary end row loops (ERL) is evidence of small vessel involvement in JDM. This study aimed to examine the specific association of ERL over the disease course with evidence of JDM disease damage.

METHODS

We analyzed data from 68 initially treatment-naïve JDM children who had been observed for at least five years with multiple ERL density assessments. The JDM disease course were categorized into monocyclic short, monocyclic long, polycyclic, and chronic. The ERL capillary count was cumulatively evaluated using the area under the curve (AUC) method.

RESULTS

The mean ERL density for the treatment-naive JDM was significantly lower than that of their healthy age-matched controls (4.8 ± 1.6 /mm vs. 7.9 ± 0.9 /mm; p < 0.0001). The ERL AUC was significantly lower in children with a chronic disease course compared to those with a monocyclic short (p = 0.001) or monocyclic long disease course (p = 0.013). JDM patients with lipodystrophy had lower ERL AUC than those without lipodystrophy (p = 0.04). There was no association between ERL AUC and calcifications or fractures.

CONCLUSION

Persistently decreased ERL capillary density, reflected by low ERL AUC, is associated with a chronic disease course and lipodystrophy in JDM. Despite medical therapy, the mean ERL count remained below normal even after five years, particularly in polycyclic and chronic cases. It is not clear that restoring normal capillary density is currently feasible in children with JDM.

A subtype of laminopathies: Generalized lipodystrophy-associated progeroid syndrome caused by LMNA gene c.29C>T mutation

The term laminopathies refers to a group of congenital diseases characterized by accelerated degeneration of human tissues. Mutations in LMNA, LMNB, ZMPSTE24, and other genes lead to structural and functional abnormalities associated with lamins. One subtype of laminopathy is the generalized lipodystrophy-associated progeroid syndrome (GLPS), which occurs in patients with heterozygous mutations of the LMNA gene c.29C>T(p.T10I). This paper reports the first case of GLPS in China and compares the clinical features of other GLPS patients with literature reports. A 16-year-old male patient was treated for diabetic ketoacidosis, presenting with premature aging appearance, systemic lipodystrophy, severe fatty liver, and decreased bone density. After peripheral blood DNA extraction and second-generation sequencing, a heterozygous mutation of exon 1 of the LMNA gene c.29C>T(p.T10I) was detected. This case of GLPS may provide a diagnostic and therapeutic basis for potential patients.

Delayed Presentation of Berardinelli-Siep Lipodystrophy in an Adolescent Female

Berardinelli-Siep syndrome (BSS) is a form of congenital generalized lipodystrophy that disrupts the pathways of lipid metabolism. It presents with physical exam findings, including muscular hypertrophy and lipoatrophy as well as serious metabolic consequences such as diabetes mellitus, hypertriglyceridemia, acute pancreatitis, hepatomegaly, and hepatic steatosis. Diagnosis generally occurs soon after birth or in childhood. The case presented is significant for a delayed diagnosis of suspected BSS Type 1 which is rather uncommon in a developed country. Due to the detrimental complications of BSS, such as hypertrophic cardiomyopathy, pancreatitis, and liver disease, early diagnosis and intervention are crucial. Pediatric providers must be knowledgeable about physical features of BSS and common presentations such as new onset diabetes, hypertriglyceridemia, or pancreatitis throughout early childhood and adolescence in order to avoid delayed diagnoses.

Lipodystrophy-associated progeroid syndromes

With the exception of HIV-associated lipodystrophy, lipodystrophy syndromes are rare conditions characterized by a lack of adipose tissue, which is not generally recovered. As a consequence, an ectopic deposition of lipids frequently occurs, which usually leads to insulin resistance, atherogenic dyslipidemia, and hepatic steatosis. These disorders include certain accelerated aging syndromes or progeroid syndromes. Even though each of them has unique clinical features, most show common clinical characteristics that affect growth, skin and appendages, adipose tissue, muscle, and bone and, in some of them, life expectancy is reduced. Although the molecular bases of these Mendelian disorders are very diverse and not well known, genomic instability is frequent as a consequence of impairment of nuclear organization, chromatin structure, and DNA repair, as well as epigenetic dysregulation and mitochondrial dysfunction. In this review, the main clinical features of the lipodystrophy-associated progeroid syndromes will be described along with their causes and pathogenic mechanisms, and an attempt will be made to identify which of López-Otín's hallmarks of aging are present.

The acromegaly lipodystrophy

Growth hormone (GH) and insulin-like growth factor 1 (IGF-1) are essential to normal growth, metabolism, and body composition, but in acromegaly, excesses of these hormones strikingly alter them. In recent years, the use of modern methodologies to assess body composition in patients with acromegaly has revealed novel aspects of the acromegaly phenotype. In particular, acromegaly presents a unique pattern of body composition changes in the setting of insulin resistance that we propose herein to be considered an acromegaly-specific lipodystrophy. The lipodystrophy, initiated by a distinctive GH-driven adipose tissue dysregulation, features insulin resistance in the setting of reduced visceral adipose tissue (VAT) mass and intra-hepatic lipid (IHL) but with lipid redistribution, resulting in ectopic lipid deposition in muscle. With recovery of the lipodystrophy, adipose tissue mass, especially that of VAT and IHL, rises, but insulin resistance is lessened. Abnormalities of adipose tissue adipokines may play a role in the disordered adipose tissue metabolism and insulin resistance of the lipodystrophy. The orexigenic hormone ghrelin and peptide Agouti-related peptide may also be affected by active acromegaly as well as variably by acromegaly therapies, which may contribute to the lipodystrophy. Understanding the pathophysiology of the lipodystrophy and how acromegaly therapies differentially reverse its features may be important to optimizing the long-term outcome for patients with this disease. This perspective describes evidence in support of this acromegaly lipodystrophy model and its relevance to acromegaly pathophysiology and the treatment of patients with acromegaly.

Coexistence of Colon Perforation and Congenital Lipodystrophy

Lipodystrophy (LD) is an acquired or congenital rare condition consisting of hyperlipidaemia, glucose intolerance/ insulin resistance, and almost complete absence and storage of adipose tissue. Colon perforations can be observed in type 4 congenital LD. Here, we aimed to present a case of sigmoid colon perforation which developed in a young woman with the diagnosis of LD. Extensive purulent peritonitis, significant wall thickening, and oedema in the sigmoid colon were detected during surgical exploration. Anterior resection with end colostomy procedure was then performed. Although bowel perforation has been theoretically reported to occur in LD, the presented case is the first adult patient in the literature. These individuals tend to develop colon perforation as a result of histological changes in their gastrointestinal tract. This situation should always be taken into consideration in order to avoid delay in diagnosis, especially in patients who present with abdominal pain and have a history of LD. Key Words: Intestinal perforation, Congenital lipodystrophy, Peritonitis, Sigmoid colon.

Synergic effect of metabolic syndrome and lipodystrophy on oxidative stress and inflammation process in treated HIV-patients

The aim of this study was to assess the effect of lipodystrophy (LD) associated to metabolic syndrome (MS) on oxidative stress and inflammation in a cohort of 243 HIV-infected patients with MS, all of them under three different antiretroviral regimens. We collected immunovirological, biochemical and metabolic data, as well as anthropometric measurements. In addition, cardiovascular risk was also assessed by means of Atherogenic Index of Plasma (API) and Framingham Risk Score. The MS-LD patient set was characterized by a lower initial lymphocyte CD4 count and CD4/CD8 ratio and a higher initial viral load than the group without LD. We also found worse lipidic and glycaemic profiles (with lower HDL-cholesterol and higher triglyceride and glucose levels) in the MS-LD group. BMI, systolic blood pressure and Framingham score were significantly increased compared to MS-Non LD. In addition, patients with MS and LD had significantly higher levels of carbonylated proteins, lipid peroxidation, IL-6 and IL-8, as well as a significant decrease in the levels of leptin, adiponectin and antioxidant activities of catalase, super oxide dismutase and glutathione associated enzymes. In MS-LD HIV-1 patients, a significant negative correlation was found between Framingham Risk Score and the antioxidant biomarkers, however a positive association was found between API and protein-C reactive and carbonylated proteins. Segregating by ART, the above-mentioned conditions were worse within the MS-LD group whose treatment contained protease inhibitors, such as lopinavir. In conclusion, HIV-1 infected patients treated for at least six months, especially with regimens including PIs, showed a worsening of inflammatory process and oxidative stress.

Approach to the Patient With Lipodystrophy

Lipodystrophy constitutes a spectrum of diseases characterized by a generalized or partial absence of adipose tissue. Underscoring the role of healthy fat in maintenance of metabolic homeostasis, fat deficiency in lipodystrophy typically leads to profound metabolic disturbances including insulin resistance, hypertriglyceridemia, and ectopic fat accumulation. While rare, recent genetic studies indicate that lipodystrophy is more prevalent than has been previously thought, suggesting considerable underdiagnosis in clinical practice. In this article, we provide an overview of the etiology and management of generalized and partial lipodystrophy disorders. We bring together the latest scientific evidence and clinical guidelines and expose key gaps in knowledge. Through improved recognition of the lipodystrophy disorders, patients (and their affected family members) can be appropriately screened for cardiometabolic, noncardiometabolic, and syndromic abnormalities and undergo treatment with targeted interventions. Notably, insights gained through the study of this rare and extreme phenotype can inform our knowledge of more common disorders of adipose tissue overload, including generalized obesity.

Determination of insulin-related lipohypertrophy frequency and risk factors in patients with diabetes

INTRODUCTION

Insulin, which is used in the treatment of diabetes mellitus (DM), may lead to the development of lipohypertrophy (LH) which can negatively affect the management of diabetes mellitus. Two common methods to detect LH are palpation and superficial subcutaneous ultrasonography (SSU). We investigated the frequency of non-palpable LH using SSU, as well as examining risk factors.

METHOD

We included in our study patients who had been receiving insulin injections at least twice a day for over one year without palpable LH. The epidermis and the subcutaneous tissue thickness of each region were examined using SSU. The presence of LH and associated risk factors for LH were evaluated.

RESULTS

We included 136 patients in our study. The mean age of all patients was 52.87±14.93 years, 59.6% were female and 73.5% had type 2 DM. The duration of DM and insulin usage were 15.76±9.20 and 11.42±8.26 years, respectively. The mean body mass index (BMI) of all patients was 30.59±7.40kg/m². Non-palpable LH was detected in 87.5% (n=116) of the patients using SSU. In the multivariate logistic regression analyses, total cholesterol level, short-acting insulin dose and coronary artery disease (CAD) were associated with LH presence.

CONCLUSION

Non-palpable LH can be seen at high rates in patients who have multiple insulin injections. Palpation is likely not enough to detect LH and we believe it would be appropriate to evaluate the presence of LH using SSU, especially for those who need high-dose insulin to control hyperglycaemia.

Advances in the care of lipodystrophies

PURPOSE OF REVIEW

Lipodystrophies are a group of rare, heterogeneous disorders characterized by a lack or maldistribution of adipose tissue. Treatment focusses on the management of complications, including hypertriglyceridemia, which can be severe. Patients are predisposed to early atherosclerotic cardiovascular disease and acute pancreatitis. This review summarizes the recent advances in the treatment of lipodystrophies, with a particular focus on the treatment of hypertriglyceridemia in familial partial lipodystrophy (FPLD).

RECENT FINDINGS

Treatment of dyslipidemia in FPLD requires management of secondary exacerbating factors, particularly insulin resistance and diabetes, together with modification of atherosclerotic cardiovascular disease risk factors. In addition, specific lipid-lowering therapies are usually needed, starting with statins and fibrates. Leptin therapy improves triglycerides. Several emerging treatments for hypertriglyceridemia include apo C-III antagonists (volanesorsen, AKCEA-APOCIII-LRx and ARO-APOC3) and angiopoietin-like 3 antagonists (evinacumab, vupanorsen and ARO-ANG3); efficacy observed in clinical trials of these agents in nonlipodystrophic patients with severe hypertriglyceridemia suggests that they may also be helpful in lipodystrophy.

SUMMARY

Emerging therapies for dyslipidemia show promise in advancing the care of patients with lipodystrophy. However, these treatments are not yet approved for use in lipodystrophy. Further study of their efficacy and safety in this patient population is needed.

Different sites of actions make different responses to thiazolidinediones between mouse and rat models of fatty liver

Therapeutic approach for NAFLD is limited and there are no approved drugs. Pioglitazone (PGZ), a thiazolidinedione (TZD) that acts via peroxisome proliferator activated receptor gamma (PPARγ) is the only agent that has shown consistent benefit and efficacy in clinical trials. However, the mechanism of its therapeutic effect on NAFLD remains unclear. The poor understanding may be due to problems with mouse, a species most used for animal experiments. TZDs exacerbate fatty liver in mouse models while they improve it in rat models like in human patients. Therefore, we compared the effects of TZDs including PGZ and rosiglitazone (RGZ) in ob/ob mice and Lepmkyo/Lepmkyo rats, models of leptin-deficient obesity, and A-ZIP/F-1 mice and seipin knockout (SKO) rats, models of generalized lipodystrophy. Pparg mRNA expression was markedly upregulated in fatty livers of mouse models while it was unchanged in rat models. TZDs exacerbated fatty liver in ob/ob and A-ZIP/F-1 mice, improved it in Lepmkyo/Lepmkyo rats and showed no effect in SKO rats. Gene expression analyses of Pparg and its target gene, Fsp27 revealed that PPARγ in the adipose tissue is the exclusive therapeutic target of TZDs in rats but PPARγ in the liver in addition to the adipose tissue is also a major site of actions for TZDs in mice. Although the response to TZDs in mice is the complete opposite of that in human patients, no report has pointed out the problem with TZD studies using mouse models so far. The present study might provide useful suggestions in research on TZDs.

Non-glycemic Adverse Effects of Insulin

Insulin is primarily considered for its glycemic effects in patients with diabetes. There are, however, non-glycemic adverse effects of insulin that may significantly impact patient health and interfere with glycemic control. Insulinogenic edema primarily occurs with rapid improvement in glycemic control either in patients with newly discovered diabetes or in patients with poorly-controlled diabetes. Insulin-induced sympathetic activation, vasodilation, changes in vascular permeability, and most importantly, sodium retention play significant etiologic roles in the development of edema. Clinically, it is usually self-limited, but significant complications can develop. Allergic reactions to all insulin preparations and various compounds used in insulin formulations with a wide range of severity have been reported. Frequently, changing the type of insulin or delivery method is sufficient, but more advanced treatments such as insulin desensitization and anti-IgE antibody treatment may be needed. Lipohypertrophy and lipoatrophy frequently develop with the overuse of injection sites. Lipohypertrophy can affect tissue insulin absorption and glycemic control.

Leptin Attenuates Cardiac Hypertrophy in Patients With Generalized Lipodystrophy

CONTEXT

Lipodystrophy syndromes are rare disorders of deficient adipose tissue, low leptin, and severe metabolic disease, affecting all adipose depots (generalized lipodystrophy, GLD) or only some (partial lipodystrophy, PLD). Left ventricular (LV) hypertrophy is common (especially in GLD); mechanisms may include hyperglycemia, dyslipidemia, or hyperinsulinemia.

OBJECTIVE

Determine effects of recombinant leptin (metreleptin) on cardiac structure and function in lipodystrophy.

METHODS

Open-label treatment study of 38 subjects (18 GLD, 20 PLD) at the National Institutes of Health before and after 1 (N = 27), and 3 to 5 years (N = 23) of metreleptin. Outcomes were echocardiograms, blood pressure (BP), triglycerides, A1c, and homeostasis model assessment of insulin resistance.

RESULTS

In GLD, metreleptin lowered triglycerides (median [interquartile range] 740 [403-1239], 138 [88-196], 211 [136-558] mg/dL at baseline, 1 year, 3-5 years, P < .0001), A1c (9.5 ± 3.0, 6.5 ± 1.6, 6.5 ± 1.9%, P < .001), and HOMA-IR (34.1 [15.2-43.5], 8.7 [2.4-16.0], 8.9 [2.1-16.4], P < .001). Only HOMA-IR improved in PLD (P < .01). Systolic BP decreased in GLD but not PLD. Metreleptin improved cardiac parameters in patients with GLD, including reduced posterior wall thickness (9.8 ± 1.7, 9.1 ± 1.3, 8.3 ± 1.7 mm, P < .01), and LV mass (140.7 ± 45.9, 128.7 ± 37.9, 110.9 ± 29.1 g, P < .01), and increased septal e' velocity (8.6 ± 1.7, 10.0 ± 2.1, 10.7 ± 2.4 cm/s, P < .01). Changes remained significant after adjustment for BP. In GLD, multivariate models suggested that reduced posterior wall thickness and LV mass index correlated with reduced triglycerides and increased septal e' velocity correlated with reduced A1c. No changes in echocardiographic parameters were seen in PLD.

CONCLUSION

Metreleptin attenuated cardiac hypertrophy and improved septal e' velocity in GLD, which may be mediated by reduced lipotoxicity and glucose toxicity. The applicability of these findings to leptin-sufficient populations remains to be determined.

Lipodystrophies-Disorders of the Fatty Tissue

Lipodystrophies are a heterogeneous group of physiological changes characterized by a selective loss of fatty tissue. Here, no fat cells are present, either through lack of differentiation, loss of function or premature apoptosis. As a consequence, lipids can only be stored ectopically in non-adipocytes with the major health consequences as fatty liver and insulin resistance. This is a crucial difference to being slim where the fat cells are present and store lipids if needed. A simple clinical classification of lipodystrophies is based on congenital vs. acquired and generalized vs. partial disturbance of fat distribution. Complications in patients with lipodystrophy depend on the clinical manifestations. For example, in diabetes mellitus microangiopathic complications such as nephropathy, retinopathy and neuropathy may develop. In addition, due to ectopic lipid accumulation in the liver, fatty liver hepatitis may also develop, possibly with cirrhosis. The consequences of extreme hypertriglyceridemia are typically acute pancreatitis or eruptive xanthomas. The combination of severe hyperglycemia with dyslipidemia and signs of insulin resistance can lead to premature atherosclerosis with its associated complications of coronary heart disease, peripheral vascular disease and cerebrovascular changes. Overall, lipodystrophy is rare with an estimated incidence for congenital (<1/1.000.000) and acquired (1-9/100.000) forms. Due to the rarity of the syndrome and the phenotypic range of metabolic complications, only studies with limited patient numbers can be considered. Experimental animal models are therefore useful to understand the molecular mechanisms in lipodystrophy and to identify possible therapeutic approaches.

Association of the polymorphisms of the genes APOC3 (rs2854116), ESR2 (rs3020450), HFE (rs1799945), MMP1 (rs1799750) and PPARG (rs1801282) with lipodystrophy in people living with HIV on antiretroviral therapy: a systematic review

The aim of this study was to perform a systematic review to identify data reported in the literature concerning the association of APOC3 (rs2854116), ESR2 (rs3020450), HFE (rs1799945), MMP1 (rs1799750) and PPARG (rs1801282) polymorphisms with lipodystrophy in people living with HIV (PLWHIV) on antirretroviral therapy. The research was conducted in six databases and the studies were selected in two steps. First, a search was undertaken in the following electronic databases: PubMed, Science Direct, Medline, World Wide Science, Directory of Open Access Journals, Scielo, Lilacs and Medcarib. The titles and abstracts of 24,859 articles were read to select those that match the elegibilty criteria. Five papers that addressed the association of HAART, lipodystrophy and polymorphisms were selected for the review. There was no association between the polymorphisms of the genes APOC3 and PPARG and lipodystrophy. Another study described an association between the variant allele (G) of HFE and protection concerning the development of lipoatrophy (0.02) when compared with the reference allele (C). On the other hand, the variant allele (T) of the ESR2 gene was associated with the development of lipoatrophy (p = 0.007) when compared with the reference allele (C). In addition, the genotype and the variant allele of the gene MMP1 (2G) were associated with lipodystrophy in PLWHIV on HAART (p = 0.0002 and p = 0.0008, respectively). Therefore, further studies with other populations, involving PLWHIV on HAART are necessary to better understand the role of genetic markers, which may be involved in a predisposition to lipodystrophy.

Comorbidities and Survival in Patients With Lipodystrophy: An International Chart Review Study

CONTEXT

Limited natural history data are available in patients with non-HIV-related lipodystrophy syndromes who never received disease-specific therapies, making interpretation of benefits of therapies in lipodystrophy syndromes challenging.

OBJECTIVE

We assessed the natural history of non-HIV-related generalized lipodystrophy (GL) and partial lipodystrophy (PL) in patients who have never received leptin or other lipodystrophy-specific therapies.

DESIGN/SETTING/PATIENTS

We conducted an international chart review of 230 patients with confirmed GL or PL at five treatment centers who never received leptin or other lipodystrophy-specific therapies. Patients were observed from birth to loss to follow-up, death, or date of chart abstraction.

OUTCOME MEASURES

Lifetime prevalence of diabetes/insulin resistance and select organ abnormalities, time to diabetes/insulin resistance, first organ abnormality, disease progression, and mortality were described.

RESULTS

Diabetes/insulin resistance was identified in 58.3% of patients. Liver abnormalities were the most common organ abnormality (71.7%), followed by kidney (40.4%), heart (30.4%), and pancreatitis (13.0%). Kaplan-Meier estimates of mean (SE) time to first organ abnormality were 7.7 years (0.9) in GL and 16.1 years (1.5) in PL (P < 0.001). Mean time to diabetes/insulin resistance was 12.7 years (1.2) in GL and 19.1 years (1.7) in PL (P = 0.131). Mean time to disease progression was 7.6 years (0.8) and comparable between GL and PL subgroups (P = 0.393). Mean time to death was 51.2 years (3.5) in GL and 66.6 years (1.0) in PL (P < 0.001).

CONCLUSIONS

This large-scale study provides comprehensive, long-term data across multiple countries on the natural history of non-HIV-related lipodystrophy.

Recent advances in understanding lipodystrophy: a focus on lipodystrophy-associated cardiovascular disease and potential effects of leptin therapy on cardiovascular function

Lipodystrophy is a disease characterized by a partial or total absence of adipose tissue leading to severe metabolic derangements including marked insulin resistance, type 2 diabetes, hypertriglyceridemia, and steatohepatitis. Lipodystrophy is also a source of major cardiovascular disorders which, in addition to hepatic failure and infection, contribute to a significant reduction in life expectancy. Metreleptin, the synthetic analog of the adipocyte-derived hormone leptin and current therapy of choice for patients with lipodystrophy, successfully improves metabolic function. However, while leptin has been associated with hypertension, vascular diseases, and inflammation in the context of obesity, it remains unknown whether its daily administration could further impair cardiovascular function in patients with lipodystrophy. The goal of this short review is to describe the cardiovascular phenotype of patients with lipodystrophy, speculate on the etiology of the disorders, and discuss how the use of murine models of lipodystrophy could be beneficial to address the question of the contribution of leptin to lipodystrophy-associated cardiovascular disease.

Recent developments in lipodystrophy

PURPOSE OF REVIEW

Lipodystrophy syndromes have an estimated prevalence of 1.3-4.7 cases per million and as with other rare diseases conducting research can be challenging. The present review highlights recently published work that has provided insights into the field of non-HIV--associated lipodystrophy syndromes.

RECENT FINDINGS

Lipodystrophies are a heterogenous group of disorders, as such research is often focused on specific subtypes of the condition. The identification of children carrying LMNA mutations has provided insights into the natural history of FPLD2, specifically that the adipose tissue phenotype predates the onset of puberty. Recent reports of PLIN1 heterozygous null variant carriers and the apparent absence of a lipodystrophy phenotype challenges our understanding of the molecular biology of perilipin 1 and its role in the pathogenesis of FPLD4. With a focus on therapeutics, studies delineating the differential responsiveness of PPARγ mutants to endogenous and synthetic ligands has illustrated the potential for pharmacogenetics to inform therapeutic decisions in lipodystrophy related to PPARG mutations, whereas robust human studies have provided insight into the food independent metabolic effects of leptin in lipodystrophy. Finally, rare syndromes of lipodystrophy continue to serve as an exemplar for the contribution of genetically determined adipose tissue expandability to metabolic disease in the general population.

SUMMARY

Lipodystrophy research continues to illuminate our understanding of this rare disease and the possibility that lipodystrophy syndromes and the metabolic syndrome may have shared pathophysiology.

Fatty liver in lipodystrophy: A review with a focus on therapeutic perspectives of adiponectin and/or leptin replacement

Lipodystrophy is a group of clinically heterogeneous, inherited or acquired, disorders characterized by complete or partial absence of subcutaneous adipose tissue that may occur simultaneously with the pathological, ectopic, accumulation of fat in other regions of the body, including the liver. Fatty liver adds significantly to hepatic and extra-hepatic morbidity in patients with lipodystrophy. Lipodystrophy is strongly associated with severe insulin resistance and related comorbidities, such as hyperglycemia, hyperlipidemia and nonalcoholic fatty liver disease (NAFLD), but other hepatic diseases may co-exist in some types of lipodystrophy, including autoimmune hepatitis in acquired lipodystrophies, or viral hepatitis in human immunodeficiency virus (HIV)-associated lipodystrophy. The aim of this review is to summarize evidence linking lipodystrophy with hepatic disease and to provide a special focus on potential therapeutic perspectives of leptin replacement therapy and adiponectin upregulation in lipodystrophy.

Monogenic forms of lipodystrophic syndromes: diagnosis, detection, and practical management considerations from clinical cases

BACKGROUND

Lipodystrophic syndromes are rare diseases of genetic or acquired origin characterized by partial or generalized lack of body fat. Early detection and diagnosis are crucial to prevent and manage associated metabolic dysfunctions, i.e. insulin resistance, dyslipidemia, fatty liver, and diabetes, and to provide appropriate genetic counseling. By means of several representative case studies, this article illustrates the diagnostic and management challenges of lipodystrophic syndromes.

REVIEW

Berardinelli-Seip congenital lipodystrophy (BSCL) is typically diagnosed at birth, or soon thereafter, with generalized lipoatrophy and hepatomegaly secondary to hepatic steatosis. Physicians must also consider this diagnosis in adults with atypical non-autoimmune diabetes, hypertriglyceridemia, and a lean and muscular phenotype. The BSCL1 subtype due to mutations in the AGPAT2 gene can have an unusual presentation, especially in neonates and infants. Particular attention should be paid to infants presenting failure to thrive who also have hepatomegaly and metabolic derangements. The BSCL2 sub-type due to mutations in the BSCL gene tends to be more severe than BSCL1, and is characterized by greater fat loss, mild intellectual disability, earlier onset of diabetes, and higher incidence of premature death. Effective management from an earlier age may moderate the natural disease course. Partial lipodystrophies may easily be confused with common central obesity and/or metabolic syndrome. In patients with unexplained pancreatitis and hypertriglyceridemia, lipodystrophies such as familial partial lipodystrophy type 2 (FPLD2; Dunnigan type, due to LMNA mutations) should be considered. Oral combined contraceptives, which can reveal the disease by inducing severe hypertriglyceridemia, are contraindicated. Endogenous estrogens may also lead to "unmasking" of the FPLD2 phenotype, which often appears at puberty, and is more severe in females than males.

CONCLUSIONS

Diet and exercise, adapted to age and potential comorbidities, are essential prerequisites for therapeutic management of lipodystrophic syndromes. Metreleptin therapy can be useful to manage lipodystrophy-related metabolic complications.

A subset of patients with acquired partial lipodystrophy developing severe metabolic abnormalities

Purpose/Aim of the study: Acquired partial lipodystrophy (APL) is a rare disease characterized by selective loss of adipose tissue. In this study, we aimed to present a subset of patients with APL, who developed severe metabolic abnormalities, from our national lipodystrophy registry.

MATERIALS AND METHODS

Severe metabolic abnormalities were defined as: poorly controlled diabetes (HbA1c above 7% despite treatment with insulin more than 1 unit/kg/day combined with oral antidiabetics), severe hypertriglyceridemia (triglycerides above 500 mg/dL despite treatment with lipid-lowering drugs), episodes of acute pancreatitis, or severe hepatic involvement (biopsy-proven non-alcoholic steatohepatitis (NASH)).

RESULTS

Among 140 patients with all forms of lipodystrophy (28 with APL), we identified 6 APL patients with severe metabolic abnormalities. The geometric mean for age was 37 years (range: 27-50 years; 4 females and 2 males). Five patients had poorly controlled diabetes despite treatment with high-dose insulin combined with oral antidiabetics. Severe hypertriglyceridemia developed in five patients, of those three experienced episodes of acute pancreatitis. Although all six patients had hepatic steatosis at various levels on imaging studies, NASH was proven in two patients on liver biopsy. Our data suggested that APL patients with severe metabolic abnormalities had a more advanced fat loss and longer disease duration.

CONCLUSIONS

We suggest that these patients represent a potential subgroup of APL who may benefit from metreleptin or investigational therapies as standard treatment strategies fail to achieve a good metabolic control.

Effect of Insulin-Induced Lipodystrophy on Glycemic Control among Children and Adolescents with Diabetes in Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia

BACKGROUND

Lipodystrophy is one of the clinical complications of insulin injection that affects insulin absorption and leads to poor glycemic control.

OBJECTIVE

To assess insulin-induced lipodystrophy and glycemic control.

METHODS

A cross sectional study was done on 176 diabetic children and adolescents who inject insulin for a minimum of one year. First, anthropometric and clinical characteristics of the patients were recorded in questionnaire, and then observation and palpation techniques were used in assessing lipodystrophy.

RESULT

Out of the total 176 participants, 103 (58.5%) had insulin-induced lipodystrophy, of them 100 (97.1%) had lipohypertrophy and 3 (2.9%) had lipoatrophy. Being younger, failure to rotate the injection site every week and multiple reuse of insulin syringe had significant influence in development of insulin-induced lipohypertrophy. Lipohypertrophy in turn was associated with the use of higher dose of insulin and nonoptimal glycemic control.

CONCLUSION

Findings of this study revealed that in spite of using recombinant human insulin, the magnitude of the lipohypertrophy still remained high. Therefore, a routine workup of insulin-injecting patients for such complication is necessary, especially in the individuals who have a nonoptimal glycemic control.

Renal complications of lipodystrophy: A closer look at the natural history of kidney disease

OBJECTIVES

Lipodystrophy syndromes are a group of heterogeneous disorders characterized by adipose tissue loss. Proteinuria is a remarkable finding in previous reports.

STUDY DESIGN

In this multicentre study, prospective follow-up data were collected from 103 subjects with non-HIV-associated lipodystrophy registered in the Turkish Lipodystrophy Study Group database to study renal complications in treatment naïve patients with lipodystrophy.

METHODS

Main outcome measures included ascertainment of chronic kidney disease (CKD) by studying the level of proteinuria and the estimated glomerular filtration rate (eGFR). Kidney volume was measured. Percutaneous renal biopsies were performed in 9 patients.

RESULTS

Seventeen of 37 patients with generalized and 29 of 66 patients with partial lipodystrophy had CKD characterized by proteinuria, of those 12 progressed to renal failure subsequently. The onset of renal complications was significantly earlier in patients with generalized lipodystrophy. Patients with CKD were older and more insulin resistant and had worse metabolic control. Increased kidney volume was associated with poor metabolic control and suppressed leptin levels. Renal biopsies revealed thickening of glomerular basal membranes, mesangial matrix abnormalities, podocyte injury, focal segmental sclerosis, ischaemic changes and tubular abnormalities at various levels. Lipid vacuoles were visualized in electron microscopy images.

CONCLUSIONS

CKD is conspicuously frequent in patients with lipodystrophy which has an early onset. Renal involvement appears multifactorial. While poorly controlled diabetes caused by severe insulin resistance may drive the disease in some cases, inherent underlying genetic defects may also lead to cell autonomous mechanisms contributory to the pathogenesis of kidney disease.

Transgenic Mice Overexpressing SREBP-1a in Male ob/ob Mice Exhibit Lipodystrophy and Exacerbate Insulin Resistance

Sterol regulatory element-binding protein (SREBP)-1a is a key transcription factor that activates the expression of genes involved in the synthesis of fatty acids, triglycerides (TGs), and cholesterol. Transgenic mice that overexpress the nuclear form of SREBP-1a under the control of the phosphoenolpyruvate carboxykinase promoter (Tg-1a) were previously shown to display a lipodystrophic phenotype characterized by enlarged and fatty livers, diminished peripheral white adipose tissue (WAT), and insulin resistance. In the current study, we crossed these Tg-1a mice with genetically obese (ob/ob) mice (Tg-1a;ob/ob) and examined change in fat distribution between liver and adipose tissues in severe obesity and mechanism underlying the lipodystrophic phenotype in mice with Tg-1a. Tg-1a;ob/ob mice developed more severe steatohepatitis but had reduced WAT mass and body weight compared with ob/ob mice. The reduction of WAT mass in Tg-1a and Tg-1a;ob/ob mice was accompanied by enhanced lipogenesis and lipid uptake in the liver, reduced plasma lipid levels, impaired adipocyte differentiation, reduced food intake, enhanced energy expenditure, and extended macrophage infiltration and fibrosis in WAT. Despite the improved glucose tolerance, Tg-1a;ob/ob mice showed severe peripheral insulin resistance. Adenoviral hepatic expression of SREBP-1a mimicked these phenotypes. The "fat steal"-like lipodystrophy phenotype of the Tg-1a;ob/ob model demonstrates that hepatic SREBP-1a activation has a strong impact on the partition of TG accumulation, resulting in adipose-tissue remodeling by inflammation and fibrosis and insulin resistance.

Lipoatrophy/lipohypertrophy outcomes after antiretroviral therapy switch in children in the UK/Ireland

BACKGROUND

Following widespread use of stavudine, a thymidine analogue, in antiretroviral therapy (ART) over the past three decades, up to a third of children developed lipoatrophy (LA) and/or lipohypertrophy (LH). Following phasing-out of stavudine, incidence of newly-diagnosed LA and LH declined dramatically. However, the natural history of existing cases should be explored, particularly with prolonged protease inhibitor exposure.

METHODS

The Collaborative HIV Paediatric Study (CHIPS) is a multicentre cohort study of most HIV-infected children in the United Kingdom and Ireland. Those on ART with a LA/LH assessment recorded in 2003-2011 were included. Assessments were completed annually by consultant physicians. Using the 0-3 grading system, LA or LH was defined as grade 2 or 3. Resolution was defined as return to grade 1 or 0 in all body regions.

RESULTS

Of 1345 children followed for median (IQR) 5.5 (2.9, 8.2) years after ART initiation, 30 developed LA and 27 developed LH, all at least 2 years after ART initiation. Median age at LA diagnosis was 11 (10, 13) years and at LH diagnosis was 13 (11, 15) years. Children with LA were more likely white (p<0.0001); lower height-for-age z-score at ART initiation (p = 0.02); initiated ART earlier (p = 0.04), with longer ART exposure (p = 0.04). Children with LH were similar to those without. Analysis of individual drugs revealed that LA was associated with greater duration of exposure to stavudine and didanosine; while LH was associated with greater duration of exposure to stavudine and ritonavir (given alone or in combination with another protease inhibitor). Median time in follow-up following ART switch was 2.8 (1.9, 4.9) and 2.5 (1.6, 4.7) years respectively. Resolution occurred in 10 (30%) of LA cases (median time to resolution 2.3 [1.8, 3.6] years) and 3 (11%) of LH cases (median time to resolution 2.0 [1.7, 2.1] years).

CONCLUSIONS

Prevalence of LA and LH were low, with some resolution noted, especially for LA. More long-term data are needed.

Definitive diagnosis of mandibular hypoplasia, deafness, progeroid features and lipodystrophy (MDPL) syndrome caused by a recurrent de novo mutation in the POLD1 gene

Segmental progeroid syndromes with lipodystrophy are extremely rare, heterogeneous, and complex multi-system disorders that are characterized by phenotypic features of premature aging affecting various tissues and organs. In this study, we present a "sporadic/isolated" Japanese woman who was ultimately diagnosed with mandibular hypoplasia, deafness, progeroid features, and progressive lipodystrophy (MDPL) syndrome (MIM #615381) using whole exome sequencing analysis. She had been suspected as having atypical Werner syndrome and/or progeroid syndrome based on observations spanning a 30-year period; however, repeated genetic testing by Sanger sequencing did not identify any causative mutation related to various subtypes of congenital partial lipodystrophy (CPLD) and/or mandibular dysplasia with lipodystrophy (MAD). Recently, MDPL syndrome has been described as a new entity showing progressive lipodystrophy. Furthermore, polymerase delta 1 (POLD1) gene mutations on chromosome 19 have been identified in patients with MDPL syndrome. To date, 21 cases with POLD1-related MDPL syndrome have been reported worldwide, albeit almost entirely of European origin. Here, we identified a de novo mutation in exon 15 (p.Ser605del) of the POLD1 gene in a Japanese case by whole exome sequencing. To the best of our knowledge, this is the first identified case of MDPL syndrome in Japan. Our results provide further evidence that mutations in POLD1 are responsible for MDPL syndrome and serve as a common genetic determinant across different ethnicities.

Low expression of IL-18 and IL-18 receptor in human skeletal muscle is associated with systemic and intramuscular lipid metabolism-Role of HIV lipodystrophy

Introduction

Interleukin (IL)-18 is involved in regulation of lipid and glucose metabolism. Mice lacking whole-body IL-18 signalling are prone to develop weight gain and insulin resistance, a phenotype which is associated with impaired fat oxidation and ectopic skeletal muscle lipid deposition. IL-18 mRNA is expressed in human skeletal muscle but a role for IL-18 in muscle has not been identified. Patients with HIV-infection and lipodystrophy (LD) are characterized by lipid and glucose disturbances and increased levels of circulating IL-18. We hypothesized that skeletal muscle IL-18 and IL-18 receptor (R) expression would be altered in patients with HIV-lipodystrophy.

Design and methods

Twenty-three HIV-infected patients with LD and 15 age-matched healthy controls were included in a cross-sectional study. Biopsies from the vastus lateralis muscle were obtained and IL-18 and IL-18R mRNA expression were measured by real-time PCR and sphingolipids (ceramides, sphingosine, sphingosine-1-Phosphate, sphinganine) were measured by HPLC. Insulin resistance was assessed by HOMA and the insulin response during an OGTT.

Results

Patients with HIV-LD had a 60% and 54% lower level of muscular IL-18 and IL-18R mRNA expression, respectively, compared to age-matched healthy controls. Patients with HIV-LD had a trend towards increased levels of ceramide (18.3±4.7 versus 14.8±3.0,p = 0.06) and sphingosine (0.41±0.13 versus 0.32±0.07, and lower level of sphinganine (p = 0.06). Low levels of muscle IL-18 mRNA correlated to high levels of ceramides (r = -0.31, p = 0.038) and sphingosine-1P (r = -0.29, p = 0.046) in skeletal muscle, whereas such a correlation was not found in healthy controls. Low expression of IL-18 mRNA in skeletal muscle correlated to elevated concentration of circulating triglycerides (R_p = -0.73, p<0.0001). Neither muscle expression of IL-18 mRNA or ceramide correlated to parameters of insulin resistance.

Conclusion

IL-18 (mRNA) in skeletal muscle appears to be involved in the regulation of intramuscular lipid metabolism and hypertriglyceridemia.

Genetics of Lipodystrophy

Lipodystrophy disorders are characterized by selective loss of fat tissue with metabolic complications including insulin resistance, hypertriglyceridemia, and nonalcoholic liver disease. These complications can be life-threatening, affect quality of life, and result in increased health care costs. Genetic discoveries have been particularly helpful in understanding the pathophysiology of these diseases, and have shown that mutations affect pathways involved in adipocyte differentiation and survival, lipid droplet formation, and lipid synthesis. In addition, genetic testing can identify patients whose phenotypes are not clearly apparent, but who may still be affected by severe metabolic complications.

High FGF21 levels are associated with altered bone homeostasis in HIV-1-infected patients

BACKGROUND

Fibroblast growth factor-21 (FGF21) has emerged as an important regulator of glucose, lipid, and body weight homeostasis. However, recent experimental studies have reported that increased FGF21 levels may lead to bone loss.

OBJECTIVE

To assess the relationship of serum FGF21 levels and altered bone homeostasis in HIV-1-infected patients.

DESIGN

Cross-sectional study of 137 HIV-1-infected patients and 35 healthy controls conducted at the Hospital de la Santa Creu i Sant Pau, Barcelona. Among HIV-1-infected patients, 35 were untreated (naïve), 43 were treated with antiretrovirals (HIV-1/ART) with no lipodystrophy, and 59 patients were HIV-1/ART and experienced lipodystrophy. Bone mineral density (BMD) and content (BMC) were assessed using dual-energy X-ray absorptiometry. Serum levels of FGF21, receptor activator of nuclear factor (NF)-KB ligand (RANKL), and C-telopeptide of type-I collagen (CTX-1) were measured by enzyme-linked immunosorbent assays. Serum levels of osteocalcin, osteoprotegerin, leptin, tumor necrosis factor-α, interleukin-6, interleukin-8, and monocyte chemoattractant protein-1 were determined using an antibody-linked, fluorescently labeled microsphere bead-based multiplex analysis system.

RESULTS

Alterations in bone parameters and bone homeostasis marker levels were consistent with higher turnover and bone loss in HIV-1 infected patients. FGF21 correlated negatively with BMD and BMC. FGF21 correlated positively with serum levels of osteoprotegerin and CTX-1, as well as with the CTX-1/osteocalcin ratio.

CONCLUSIONS

Elevated FGF21 levels are associated with poor bone homeostasis in HIV-1-infected patients. Increases in FGF21 serum level may be an indicator not only of metabolic derangement but it may also serve as a biomarker of altered bone homeostasis in HIV-1 infected patients.

Correlation of Leptin, Adiponectin, and Resistin Levels in Different Types of Lipodystrophy in HIV/AIDS Patients

BACKGROUND

Leptin, adiponectin, and resistin may play an important role in the development of lipodystrophy (LD) in HIV/AIDS patients. The aim of this study was to correlate levels of leptin, adiponectin, and resistin between HIV/AIDS patients with LD and without lipodystrophy (non-LD), as well as between subgroups of LD [lipoatrophy (LA), lipohypertrophy (LH), and mixed fat redistribution (MFR)] and non-LD patients.

METHODS

Cross-sectional study of 66 HIV/AIDS patients. Serum levels of leptin, adiponectin, and resistin were measured. The associations between adipocytokine levels and metabolic variables were estimated by Spearman correlation. Analysis of covariance with bootstrapping method was used to examine the relationship between adiponectin and leptin and lipodystrophy categories.

RESULTS

The LD was observed in 29 (44%) patients, while 15 (52%) of them had LA, 4 (14%) had LH, and 10 (34%) patients had MFR. No significant differences regarding leptin, adiponectin, and resistin levels, between LD and non-LD patients, were observed. LH patients had significantly higher levels of leptin and adiponectin in comparison with non-LD patients (P = 0.039, P = 0.011, respectively). Within the LD group, LA patients had significantly lower levels of leptin (LA vs. LH, P = 0.020; LA vs. MFR, P = 0.027), while LH patients had significantly higher levels of adiponectin (LH vs. LA, P = 0.027; LH vs. MFR, P = 0.028). Correlation of adiponectin with LD remains significant in the LH subgroup after adjustment for age, body mass index, cystatin-C, plasminogen activator inhibitor-1 (PAI-1), and interferon gamma (IFN-γ) (P = 0.001).

CONCLUSIONS

Adiponectin and leptin levels differ significantly between LH patients and non-LD patients, as well as between the LD subgroups. Adiponectin may be a more useful marker of LD in HIV/AIDS patients.

Lipodystrophy, Diabetes and Normal Serum Insulin in PPARγ-Deficient Neonatal Mice

Peroxisome proliferator activated receptor gamma (PPARγ) is a pleiotropic ligand activated transcription factor that acts in several tissues to regulate adipocyte differentiation, lipid metabolism, insulin sensitivity and glucose homeostasis. PPARγ also regulates cardiomyocyte homeostasis and by virtue of its obligate role in placental development is required for embryonic survival. To determine the postnatal functions of PPARγ in vivo we studied globally deficient neonatal mice produced by epiblast-restricted elimination of PPARγ. PPARγ-rescued placentas support development of PPARγ-deficient embryos that are viable and born in near normal numbers. However, PPARγ-deficient neonatal mice show severe lipodystrophy, lipemia, hepatic steatosis with focal hepatitis, relative insulin deficiency and diabetes beginning soon after birth and culminating in failure to thrive and neonatal lethality between 4 and 10 days of age. These abnormalities are not observed with selective PPARγ2 deficiency or with deficiency restricted to hepatocytes, skeletal muscle, adipocytes, cardiomyocytes, endothelium or pancreatic beta cells. These observations suggest important but previously unappreciated functions for PPARγ1 in the neonatal period either alone or in combination with PPARγ2 in lipid metabolism, glucose homeostasis and insulin sensitivity.

Lipohypertrophy

This communication focuses on lipohypertrophy (LH), which is a commonly seen, yet easily preventable insulin site reaction. LH can be detected at an early stage by regular inspection and palpation. This can prevent the excessive requirement of insulin, and the glycaemic variability that is encountered when insulin is injected into areas with LH. This article describes the etiology, clinical features and preventive measures of LH.

Improvements in Vertebral-Column Angles and Psychological Metrics After Abdominoplasty With Rectus Plication

BACKGROUND

Substantial fluctuations in body weight can result in diastasis recti and weakening of the connections between the lateral abdominal muscles and the rectus sheath.

OBJECTIVES

The authors sought to determine the postural and psychological effects of abdominoplasty with vertical rectus plication.

METHODS

Forty women with substantial back and lumbar pain owing to abdominal lipodystrophy were evaluated in a prospective study. Preoperatively and 6 months postoperatively, patients underwent bidirectional radiography of the thoracic and lumbar regions. A visual analog scale (VAS), the Beck Depression Inventory (BDI), and the Nottingham Health Profile (NHP) were applied to assess physical, psychological, and quality-of-life changes following surgery.

RESULTS

Significant improvements in posture, assessed in terms of lumbar lordosis, thoracic kyphosis, and the lumbosacral angle, were observed 6 months after abdominoplasty with rectus plication. Results of the VAS and BDI indicated significant improvements in pain and quality of life, respectively. Results of the NHP indicated significant postoperative improvements in fatigue, pain, and sleep.

CONCLUSIONS

Abdominoplasty with rectus plication improves posture by tightening the thoracolumbar fascia. In selected patients, abdominoplasty can reduce back and lumbar pain, thereby improving quality of life.

A Report of Three Cases With Acquired Generalized Lipodystrophy With Distinct Autoimmune Conditions Treated With Metreleptin

CONTEXT

Acquired generalized lipodystrophy (AGL) is associated with leptin deficiency as a result of adipose tissue loss and hypertriglyceridemia, insulin resistance, and hepatic steatosis. It may coexist with other autoimmune diseases such as Hashimoto's thyroiditis, rheumatoid arthritis, hemolytic anemia, and chronic active hepatitis. Metreleptin therapy has been shown to improve metabolic abnormalities in lipodystrophy, but the effect on AGL patients with active autoimmune disease is unknown.

CASE DESCRIPTION

We report 3 cases of pediatric patients with AGL and distinct active autoimmune diseases who were treated with metreleptin over a period of 4-6 years. Case 1 is a 9-year-old girl with active juvenile dermatomyositis, who was successfully treated with leptin with no worsening of her dermatomoysitis. Case 2 is a 16-year-old female with Graves' disease, who could discontinue all her antidiabetic medication completely with improved triglyceride levels. Case 3 is an 11-year-old boy with active autoimmune hepatitis and chronic urticaria, whose hyperphagia has resolved and his liver enzymes and hepatosplenomegaly have improved.

CONCLUSION

Metreleptin therapy is of considerable clinical benefit to reduce insulin resistance and hypertriglyceridemia and did not appear to alter the clinical course of autoimmune disease nor clinical efficacy of immunosuppressive treatments. Our observations suggest that risk or presence of autoimmune disease should not lead to withholding of metreleptin treatment from patients with AGL, but should prompt close clinical follow up in light of cautionary preclinical data.

Acquired partial lipodystrophy is associated with increased risk for developing metabolic abnormalities

OBJECTIVE

Acquired partial lipodystrophy (APL) is a rare disorder characterized by progressive selective fat loss. In previous studies, metabolic abnormalities were reported to be relatively rare in APL, whilst they were quite common in other types of lipodystrophy syndromes.

METHODS

In this nationwide cohort study, we evaluated 21 Turkish patients with APL who were enrolled in a prospective follow-up protocol. Subjects were investigated for metabolic abnormalities. Fat distribution was assessed by whole body MRI. Hepatic steatosis was evaluated by ultrasound, MRI and MR spectroscopy. Patients with diabetes underwent a mix meal stimulated C-peptide/insulin test to investigate pancreatic beta cell functions. Leptin and adiponectin levels were measured.

RESULTS

Fifteen individuals (71.4%) had at least one metabolic abnormality. Six patients (28.6%) had diabetes, 12 (57.1%) hypertrigylceridemia, 10 (47.6%) low HDL cholesterol, and 11 (52.4%) hepatic steatosis. Steatohepatitis was further confirmed in 2 patients with liver biopsy. Anti-GAD was negative in all APL patients with diabetes. APL patients with diabetes had lower leptin and adiponectin levels compared to patients with type 2 diabetes and healthy controls. However, contrary to what we observed in patients with congenital generalized lipodystrophy (CGL), we did not detect consistently very low leptin levels in APL patients. The mix meal test suggested that APL patients with diabetes had a significant amount of functional pancreatic beta cells, and their diabetes was apparently associated with insulin resistance.

CONCLUSIONS

Our results show that APL is associated with increased risk for developing metabolic abnormalities. We suggest that close long-term follow-up is required to identify and manage metabolic abnormalities in APL.

PPARγ mutations, lipodystrophy and diabetes

The focus of this review is the lipodystrophy syndrome caused by mutation in the PPARγ nuclear receptor - partial familial lipodystrophy FPLD3. To provide a broader context for how these mutations act to generate the clinical features of partial lipodystrophy we will review the basic biology of PPARγ and also survey the set PPARγ genetic variants that do not cause lipodystrophy, but are nonetheless associated with clinically related syndromes, specifically type 2 diabetes.

Lymphoma in acquired generalized lipodystrophy

Acquired generalized lipodystrophy (AGL) is a rare disease thought to result from autoimmune destruction of adipose tissue. Peripheral T-cell lymphoma (PTCL) has been reported in two AGL patients. We report five additional cases of lymphoma in AGL, and analyze the role of underlying autoimmunity and recombinant human leptin (metreleptin) replacement in lymphoma development. Three patients developed lymphoma during metreleptin treatment (two PTCL and one ALK-positive anaplastic large cell lymphoma), and two developed lymphomas (mycosis fungoides and Burkitt lymphoma) without metreleptin. AGL is associated with high risk for lymphoma, especially PTCL. Autoimmunity likely contributes to this risk. Lymphoma developed with or without metreleptin, suggesting metreleptin does not directly cause lymphoma development; a theoretical role of metreleptin in lymphoma progression remains possible. For most patients with AGL and severe metabolic complications, the proven benefits of metreleptin on metabolic disease will likely outweigh theoretical risks of metreleptin in lymphoma development or progression.

Current Efavirenz (EFV) or ritonavir-boosted lopinavir (LPV/r) use correlates with elevate markers of atherosclerosis in HIV-infected subjects in Addis Ababa, Ethiopia

BACKGROUND

HIV patients on antiretroviral therapy have shown elevated incidence of dyslipidemia, lipodystrophy, and cardiovascular disease (CVD). Most studies, however, focus on cohorts from developed countries, with less data available for these co-morbidities in Ethiopia and sub-Saharan Africa.

METHODS

Adult HIV-negative (n = 36), treatment naïve (n = 51), efavirenz (EFV)-treated (n = 91), nevirapine (NVP)-treated (n = 95), or ritonavir-boosted lopinavir (LPV/r)-treated (n=44) subjects were recruited from Black Lion Hospital in Addis Ababa, Ethiopia. Aortic pressure, augmentation pressure, and pulse wave velocity (PWV) were measured via applanation tonometry and carotid intima-media thickness (cIMT) and carotid arterial stiffness, and brachial artery flow-mediated dilation (FMD) were measured via non-invasive ultrasound. Body mass index, waist-to-hip circumference ratio (WHR), skinfold thickness, and self-reported fat redistribution were used to quantify lipodystrophy. CD4+ cell count, plasma HIV RNA levels, fasting glucose, total-, HDL-, and LDL-cholesterol, triglycerides, hsCRP, sVCAM-1, sICAM-1, leptin and complete blood count were measured.

RESULTS

PWV and normalized cIMT were elevate and FMD impaired in EFV- and LPV/r-treated subjects compared to NVP-treated subjects; normalized cIMT was also elevated and FMD impaired in the EFV- and LPV/r-treated subjects compared to treatment-naïve subjects. cIMT was not statistically different across groups. Treated subjects exhibited elevated markers of dyslipidemia, inflammation, and lipodystrophy. PWV was associated with age, current EFV and LPV/r used, heart rate, blood pressure, triglycerides, LDL, and hsCRP, FMD with age, HIV duration, WHR, and glucose, and cIMT with age, current EFV use, skinfold thickness, and blood pressure.

CONCLUSIONS

Current EFV- or LPV/r-treatment, but not NVP-treatment, correlated with elevated markers of atherosclerosis, which may involve mechanisms distinct from traditional risk factors.

Lipodystrophic diabetes mellitus: a lesson for other forms of diabetes?

Lipodystrophies are a genetically heterogeneous group of disorders characterized by loss of subcutaneous adipose tissue and metabolic dysfunction, including insulin resistance, increased levels of free fatty acids, abnormal adipocytokine secretion, and ectopic fat deposition, which are also observed in patients with visceral obesity and/or type 2 diabetes mellitus. Pathophysiological, biochemical, and genetic studies suggest that impairment in multiple adipose tissue functions, including adipocyte maturation, lipid storage, formation and/or maintenance of the lipid droplet, membrane composition, DNA repair efficiency, and insulin signaling, results in severe metabolic and endocrine consequences, ultimately leading to specific lipodystrophic phenotypes. In this review, recent evidences on the causes and metabolic processes of lipodystrophies will be presented, proposing a disease model that could be potentially informative for better understanding of common metabolic diseases in humans, including obesity, metabolic syndrome, and type 2 diabetes.

Membranous lipodystrophy: skeletal findings on CT and MRI

Membranous lipodystrophy, also known as Nasu-Hakola disease, is a rare hereditary condition with manifestations in the nervous and skeletal systems. The radiographic appearance of skeletal lesions has been well described in the literature. However, CT and MRI findings of lesions in the bone have not been documented to date. This report describes the radiographic, CT, MRI, and histopathologic skeletal findings in a case of membranous lipodystrophy. With corroborative pathologic findings, a diagnosis of membranous lipodystrophy on imaging allows for appropriate clinical management of disease manifestations.

Lupus Panniculitis with Combined Features of Dermatomyositis Resulting in Severe Lipoatrophy

An 11-year-old girl presented with a one-year history of multiple, hard, slightly painful subcutaneous nodules on her right cheek, upper arms, and buttock. Histology of a skin biopsy specimen showed a lobular panniculitis. Laboratory studies revealed positive ANA, anti-double strand DNA, and elevated muscle enzymes. She was diagnosed as having lupus panniculitis. During hydroxychloroquine treatment, erythema over knuckle joints developed. These unusual clinical and laboratory findings of panniculitis associated connective tissue diseases made it difficult to make a precise diagnosis. We report this unusual case of lupus panniculitis with combined features of dermatomyositis resulting in severe lipoatrophy.

HIV lipodystrophy in participants randomised to lopinavir/ritonavir (LPV/r) +2-3 nucleoside/nucleotide reverse transcriptase inhibitors (N(t)RTI) or LPV/r + raltegravir as second-line antiretroviral therapy

Objective

To compare changes over 48 weeks in body fat, lipids, Metabolic Syndrome and cardiovascular disease risk between patients randomised 1∶1 to lopinavir/ritonavir (r/LPV) plus raltegravir (RAL) compared to r/LPV plus 2–3 nucleoside/nucleotide reverse transcriptase inhibitors (N(t)RTIs) as second-line therapy.

Methods

Participants were HIV-1 positive (>16 years) failing first-line treatment (2 consecutive HIV RNA >500 copies/mL) of NNRTI +2N(t)RTI. Whole body dual energy x-ray absorptiometry was performed at baseline and week 48. Data were obtained to calculate the Metabolic Syndrome and Framingham cardiovascular disease (CVD) risk score. Linear regression was used to compare mean differences between arms. Logistic regression compared incidence of metabolic syndrome. Associations between percent limb fat changes at 48 weeks with baseline variables were assessed by backward stepwise multivariate linear regression. Analyses were adjusted for gender, body mass index and smoking status.

Results

210 participants were randomised. The mean (95% CI) increase in limb fat over 48 weeks was 15.7% (5.3, 25.9) or 0.9 kg (0.2, 1.5) in the r/LPV+N(t)RTI arm and 21.1% (11.1, 31,1) or 1.3 kg (0.7, 1.9) in the r/LPV+RAL arm, with no significant difference between treatment arms (−5.4% [−0.4 kg], p>0.1). Increases in total body fat mass (kg) and trunk fat mass (kg) were also similar between groups. Total:HDL cholesterol ratio was significantly higher in the RAL arm (mean difference −0.4 (1.4); p = 0.03), there were no other differences in lipid parameters between treatment arms. There were no statistically significant differences in CVD risk or incidence of Metabolic Syndrome between the two treatment arms. The baseline predictors of increased limb fat were high viral load, high insulin and participant's not taking lipid lowering treatment.

Conclusion

In patients switching to second line therapy, r/LPV combined with RAL demonstrated similar improvements in limb fat as an N(t)RTI + r/LPV regimen, but a worse total:HDL cholesterol ratio over 48 weeks.

Trial Registration

This clinical trial is registered on Clinicaltrials.gov, registry number NCT00931463.

Cholic acid for hepatic steatosis in patients with lipodystrophy: a randomized, controlled trial

OBJECTIVE

Hepatic steatosis is a common complication in patients with lipodystrophies and can lead to cirrhosis. There is no proven effective therapy for hepatic steatosis, but cholic acid (CA), a farnesoid X receptor agonist, has previously been shown to reduce hepatic triglyceride (TG) content in mice and serum TG in humans. Our objective was to assess clinical efficacy and tolerability of CA therapy in patients with lipodystrophy and hepatic steatosis.

DESIGN

A randomized, double-blind, placebo-controlled, crossover study.

METHODS

Eighteen patients with genetic or autoimmune lipodystrophies and elevated hepatic TG content participated in the study. The intervention was CA (15 mg/kg per day) compared with placebo for a period of 6 months each. Hepatic TG content, the primary outcome variable, was measured with (1)H magnetic resonance spectroscopy at baseline and at 3 and 6 months during each study period. Levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), and TG were secondary end points of the study.

RESULTS

Compared with placebo, CA did not reduce (median (interquartile range) hepatic TG content (14.8% (9.4-19.0%) vs 15.9% (10.5-26.5%) respectively; P=0.42) or serum TG ((340 mg/dl (233-433 mg/dl) vs 390 mg/dl (233-595 mg/dl) respectively; P=0.45)). CA therapy also did not change AST, ALT, or GGT levels. Two patients developed diarrhea and excessive flatus while taking CA and these symptoms resolved after reducing the dose of CA.

CONCLUSION

CA was well tolerated but did not reduce hepatic TG content in patients with lipodystrophy.