Lipodystrophy Syndrome Research Articles

Rare variation in LMNA underlies polycystic ovary syndrome (PCOS) pathogenesis in two independent cohorts.

Polycystic ovary syndrome (PCOS) is a common, heritable endocrinopathy that is a common cause of anovulatory infertility in reproductive age women. Variants in LMNA cause partial lipodystrophy, a syndrome with overlapping features to PCOS. We tested the hypothesis that rare variation in LMNA contributes to PCOS pathogenesis and selects a lipodystrophy-like subtype of PCOS. We sequenced LMNA by targeted sequencing a discovery cohort of 811 PCOS patients and 164 healthy controls. We then analyzed LMNA from whole-exome sequencing (WES) of a replication cohort of 718 PCOS patients and 281 healthy controls. Variation in the LMNA gene, hormone and lipid profiles of participants. In the discovery cohort, we identified 8 missense variants in 15/811 cases, and 1 variant in 1/172 reproductively healthy controls. There is strong evidence for association between the variants and PCOS compared to gnomAD non-Finnish European population controls (χ2=17, p=3.7x10-5, OR=2.9). In the replication cohort, we identified 11 unique variants in 15/718 cases, and 1 variant in 281 reproductively healthy controls. Again, there is strong evidence for association with population controls (χ2=30.5, p=3.4x10-8, OR= 4.0). In both the discovery and replication cohorts, variants in LMNA identify women with PCOS with high triglycerides and extreme insulin resistance. Rare missense variation in LMNA is reproducibly associated with PCOS and identifies some individuals with lipodystrophy-like features. The overlap between this PCOS phenotype and genetic partial lipodystrophy syndromes warrants further investigation into additional lipodystrophy genes and their potential in PCOS etiology.

Anesthetic management of a patient with mandibular hypoplasia, deafness, progeroid features, lipodystrophy syndrome: a case report

BackgroundMandibular hypoplasia, deafness, progeroid features, and lipodystrophy (MDPL) syndrome is a rare autosomal dominant disorder that presents unique challenges for anesthetic management due to its multisystemic manifestations. This report outlines the anesthetic considerations for MDPL patients based on our case experience.Case presentationA 15-year-old male with MDPL syndrome underwent testicular extraction under general anesthesia. Insertion of a peripheral venous catheter was challenging due to scleroderma-like skin. Although the facial features of MDPL syndrome suggested a difficult airway, intubation with a McGrath™ Mac video laryngoscope was successful. Despite MDPL syndrome’s association with hypertriglyceridemia due to lipodystrophy, this patient’s triglyceride levels were normal. Thiamylal and sevoflurane were used without issues such as delayed emergence from anesthesia.ConclusionsMDPL syndrome requires careful preoperative assessment and tailored anesthetic management due to potential airway challenges arising from its distinctive facial features and the possibility of altered anesthetic pharmacokinetics associated with lipodystrophy.

New Insight for Enhanced Topical Targeting of Caffeine for Effective Cellulite Treatment: In Vitro Characterization, Permeation Studies, and Histological Evaluation in Rats

Cellulite (CLT) is one of the commonly known lipodystrophy syndromes affecting post-adolescent women worldwide. It is topographically characterized by an orange-peel, dimpled skin appearance hence, it is an unacceptable cosmetic problem. CLT can be modulated by surgical procedures such as; liposuction and mesotherapy. But, these options are invasive, expensive and risky. For these reasons, topical CLT treatments are more preferred. Caffeine (CA), is a natural alkaloid that is well-known for its prominent anti-cellulite effects. However, its hydrophilicity hinders its cutaneous permeation. Therefore, in the present study CA was loaded into solid lipid nanoparticles (SLNs) by high shear homogenization/ultrasonication. CA-SLNs were prepared using Compritol® 888 ATO and stearic acid as solid lipids, and span 60 and brij™35, as lipid dispersion stabilizing agents. Formulation variables were adjusted to obtain entrapment efficiency (EE > 75%), particle size (PS < 350 nm), zeta potential (ZP < −25 mV) and polydispersity index (PDI < 0.5). CA-SLN-4 was selected and showed maximized EE (92.03 ± 0.16%), minimized PS (232.7 ± 1.90 nm), and optimum ZP (−25.15 ± 0.65 mV) and PDI values (0.24 ± 0.02). CA-SLN-4 showed superior CA release (99.44 ± 0.36%) compared to the rest CA-SLNs at 1 h. TEM analysis showed spherical, nanosized CA-SLN-4 vesicles. Con-LSM analysis showed successful CA-SLN-4 permeation transepidermally and via shunt diffusion. CA-SLN-4 incorporated into Noveon AA−1® hydrogel (CA-SLN-Ngel) showed accepted physical/rheological properties, and in vitro release profile. Histological studies showed that CA-SLN-Ngel significantly reduced mean subcutaneous fat tissue (SFT) thickness with 4.66 fold (p = 0.035) and 4.16 fold (p = 0.0001) compared to CA-gel, at 7th and 21st days, respectively. Also, significant mean SFT thickness reduction was observed compared to untreated group with 4.83 fold (p = 0.0005) and 3.83 fold (p = 0.0043), at 7th and 21st days, respectively. This study opened new avenue for CA skin delivery via advocating the importance of skin appendages. Hence, CA-SLN-Ngel could be a promising nanocosmeceutical gel for effective CLT treatment.Graphical

Exploring lipodystrophy gene expression in adipocytes: unveiling insights into the pathogenesis of insulin resistance, type 2 diabetes, and clustering diseases (metabolic syndrome) in Asian Indians.

Studying the molecular mechanisms of lipodystrophy can provide valuable insights into the pathophysiology of insulin resistance (IR), type 2 diabetes (T2D), and other clustering diseases [metabolic syndrome (MetS)] and its underlying adipocentric disease (MetS disease). A high-confidence lipodystrophy gene panel comprising 50 genes was created, and their expressions were measured in the visceral and subcutaneous (both peripheral and abdominal) adipose depots of MetS and non-MetS individuals at a tertiary care medical facility. Most lipodystrophy genes showed significant downregulation in MetS individuals compared to non-MetS individuals in both subcutaneous and visceral depots. In the abdominal compartment, all the genes showed relatively higher expression in visceral depot as compared to their subcutaneous counterpart, and this difference narrowed with increasing severity of MetS. Their expression level shows an inverse correlation with T2D, MetS, and HOMA-IR and with other T2D-related intermediate traits. Results also demonstrated that individualization of MetS patients could be done based on adipose tissue expression of just 12 genes. Adipose tissue expression of lipodystrophy genes shows an association with MetS and its intermediate phenotypic traits. Mutations of these genes are known to cause congenital lipodystrophy syndromes, whereas their altered expression in adipose tissue contributes to the pathogenesis of IR, T2D, and MetS.

7654 Unusual Case of Lipodystrophy: A Novel Disease Phenotype?

Abstract Disclosure: M. Celik Guler: None. E.D. Frontera: None. K. Hoose: None. M.C. Foss de Freitas: Advisory Board Member; Self; PTC Therapeutics. Speaker; Self; Amryt. L. Douyon: None. E.A. Oral: Advisory Board Member; Self; Amryt, Regeneron Pharmaceuticals. Consulting Fee; Self; Regeneron Pharmaceuticals, Amryt, Third Rock Ventures. Grant Recipient; Self; Regeneron Pharmaceuticals, Amryt. Research Investigator; Self; Novo Nordisk, Ionis Pharmaceuticals Inc., Fractyl, GI Dynamics, Rhythm Pharmaceuticals. Other; Self; Amryt. Background: Lipodystrophy syndromes (LD) are rare disorders characterized by varying degrees of adipose tissue deficiency that can predispose individuals to severe metabolic complications. Although these syndromes are traditionally subclassified based on inheritance patterns and the degree of adipose tissue loss, patients may exhibit highly heterogeneous clinical presentations. In this context, we report a unique case of partial lipodystrophy with an unusual distribution of adipose tissue that likely represents a novel syndrome and challenges conventional phenotypes. Clinical Case: A 60-year-old Puerto Rican female patient with medical history of type 1 diabetes mellitus (DM), obesity, hyperlipidemia, irritable bowel syndrome, asthma, and coronary artery disease was referred to us for unexplained asymmetric distribution of adipose tissue. She had chronic left posterolateral hip pain and lipoatrophy in her left lower extremity. Her medical history showed that she was born approximately 7 lbs., with no evidence of trauma during delivery. Her mother was given an unknown medication for improving circulation to the placenta. She had a morphea like rash on the arms and chest wall more prominent on the left upper body at birth. In addition, a dimple on her hip was noticed by her mother during the early stages of infancy. Despite the normal progression of neurological development (walking/climbing stairs), she always had a very mild limp. Also, her right arm was always 2 inches larger than her left arm. When she gained weight, she also put on more asymmetric weight on the left side of the abdomen and left lower torso. She had been treated with insulin injections since she was diagnosed with diabetes at the age of 11. She never demonstrated any islet cell specific antibodies. She had a normal weight until pregnancy at the age of 27, during which she gained 20 lbs. Her weight continued to increase over time, and the maximum was 212 lbs. Her examination reveals a BMI of 41.46 kg/m² with excess fat in the right arm, mid-section, left thigh, and left mons pubis. Conversely, only the left leg appears to demonstrate specific fat atrophy, with a near-total loss of adipose tissue starting from the mid-gluteal region. The hip MRI result reported moderate osteoarthritis of the left hip. EMG revealed signs of length-dependent sensorimotor axonal polyneuropathy and long duration/large amplitude motor unit potentials isolated only in the left medial gastrocnemius muscle. Triglyceride level was 73 mg/dL, HbA1c level was 6.8%, with an average total insulin dosage of around 43 IU/day. There was no history of pancreatitis due to hypertriglyceridemia. Conclusion: Our case highlights the heterogeneity of the lipodystrophy spectrum with a novel presentation of lipodystrophy. In addition, there may be homeostatic control of deposition of fat to seek symmetry between upper versus lower and right versus left sided depots. Presentation: 6/1/2024

Beyond the retina: Lipemia retinalis as a clue to Berardinelli-Seip congenital lipodystrophy syndrome

In this rare and significant scenario, a 15-year-old female recently diagnosed with type 1 diabetes mellitus presented with moderate lipemia retinalis during routine diabetic retinopathy screening. Further investigations revealed elevated triglyceride and cholesterol levels, prompting the diagnosis of Berardinelli-Seip congenital lipodystrophy syndrome. This congenital disorder, characterized by severe insulin resistance and dyslipidemia due to near-total absence of adipose tissue, emphasizes the critical role of interdisciplinary care involving ophthalmologists, endocrinologists, and geneticists. Early recognition of ocular manifestations such as lipemia retinalis is crucial for timely diagnosis and tailored treatment strategies.

6887 Unraveling the Natural History of Lipodystrophy Syndromes with LD LYNC: Time to Development of Important Comorbidities

6887 Unraveling the Natural History of Lipodystrophy Syndromes with LD LYNC: Time to Development of Important Comorbidities

Commentary: A rapid action plan to improve diagnosis and management of lipodystrophy syndromes.

Commentary: A rapid action plan to improve diagnosis and management of lipodystrophy syndromes.

Panniculitis: A Cardinal Sign of Autoinflammation.

Panniculitis was first described in the nineteenth century and is characterized by inflammation of the subcutaneous fat. It may be categorized in septal or lobular subtypes, but other histopathological features (e.g., presence of vasculitis, nature of inflammatory infiltrates, characteristics of fat necrosis) are also important for diagnostic purposes. Clinically, panniculitis is characterized by the presence of subcutaneous nodules, and both ulcerative and nonulcerative clinical subtypes have been proposed. In this review, we aimed to describe the occurrence of panniculitis in autoinflammatory disorders (AIDs) and related diseases. Among monogenic AIDs, panniculitis is common in IFN-mediated disorders. Panniculitis is a distinctive feature in proteasome-associated autoinflammatory syndromes (PRAAS), including chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature (CANDLE) syndrome and Nakajo-Nishimura syndrome. On the other hand, erythema nodosum corresponds to the most common clinical form of panniculitis and is common in polygenic AIDs, such as Behçet's syndrome, inflammatory bowel disease, and sarcoidosis. Cytophagic histiocytic panniculitis, lipoatrophic panniculitis of children, and otulipenia are rare disorders that may also present with inflammation of the subcutaneous fat. Therefore, panniculitis can identify a specific subgroup of patients with AIDs and may potentially be regarded as a cardinal sign of autoinflammation.

Disentangling the detrimental effects of local from systemic adipose tissue dysfunction on articular cartilage in the knee

ObjectiveObesity increases osteoarthritis (OA) risk due to adipose tissue dysfunction with associated metabolic syndrome and excess weight. Lipodystrophy syndromes exhibit systemic metabolic and inflammatory abnormalities similar to obesity without biomechanical overloading. Here, we used lipodystrophy mouse models to investigate the effects of systemic versus intra-articular adipose tissue dysfunction on the knee. MethodsIntra-articular adipose tissue development was studied using reporter mice. Mice with selective lipodystrophy of intra-articular adipose tissue were generated by conditional knockout (cKO) of Bscl2 in Gdf5-lineage cells, and compared with congenital Bscl2 KO mice with generalised lipodystrophy and associated systemic metabolic dysfunction. OA was induced by surgically destabilising the medial meniscus (DMM) and obesity by high-fat diet (HFD). Gene expression was analysed by quantitative RT-PCR and tissues were analysed histologically. ResultsThe infrapatellar fat pad (IFP), in contrast to overlying subcutaneous adipose tissue, developed from a template established from the Gdf5-expressing joint interzone during late embryogenesis, and was populated shortly after birth by adipocytes stochastically arising from Pdgfrα+ Gdf5-lineage progenitors. While female Bscl2 KO mice with generalised lipodystrophy developed spontaneous knee cartilage damage, Bscl2 cKO mice with intra-articular lipodystrophy did not, despite synovial hyperplasia and inflammation of the residual IFP. Furthermore, male Bscl2 cKO mice showed no worse cartilage damage after DMM. However, female Bscl2 cKO mice with intra-articular lipodystrophy showed increased susceptibility to the cartilage damaging effects of HFD-induced obesity. ConclusionOur findings emphasise the prevalent role of systemic metabolic and inflammatory effects in impairing cartilage homeostasis, with a modulatory role for intra-articular adipose tissue.

Early B-cell transcription factor-2 defect as a novel cause of lipodystrophy: disruption of the adipose tissue character and integrity.

We report a novel cause of partial lipodystrophy associated with early B cell factor 2 (EBF2) nonsense variant (EBF2 8:26033143 C>A, c.493G>T, p.E165X) in a patient with an atypical form of partial lipodystrophy. The patient presented with progressive adipose tissue loss and metabolic deterioration at pre-pubertal age. In vitro and in vivo disease modeling demonstrates that the EBF2 variant impairs adipogenesis, causing excess accumulation of undifferentiated CD34+ cells, extracellular matrix proteins, and inflammatory myeloid cells in subcutaneous adipose tissues. Thus, this EBF2 p.E165X variant disrupts adipose tissue structure and function, leading to the development of partial lipodystrophy syndrome.

A rapid action plan to improve diagnosis and management of lipodystrophy syndromes.

Lipodystrophy syndromes are rare diseases that can present with a broad range of symptoms. Delays in diagnosis are common, which in turn, may predispose to the development of severe metabolic complications and end-organ damage. Many patients with lipodystrophy syndromes are only diagnosed after significant metabolic abnormalities arise. Prompt action by clinical teams may improve disease outcomes in lipodystrophy syndromes. The aim of the Rapid Action Plan is to serve as a set of recommendations from experts that can support clinicians with limited experience in lipodystrophy syndromes. The Rapid Action Plan was developed using insights gathered through a series of advisory meetings with clinical experts in lipodystrophy syndromes. A skeleton template was used to facilitate interviews. A consensus document was developed, reviewed, and approved by all experts. Lipodystrophy is a clinical diagnosis. The Rapid Action Plan discusses tools that can help diagnose lipodystrophy syndromes. The roles of clinical and family history, physical exam, patient and family member photos, routine blood tests, leptin levels, skinfold measurements, imaging studies, and genetic testing are explored. Additional topics such as communicating the diagnosis to the patients/families and patient referrals are covered. A set of recommendations regarding screening and monitoring for metabolic diseases and end-organ abnormalities is presented. Finally, the treatment of lipodystrophy syndromes is reviewed. The Rapid Action Plan may assist clinical teams with the prompt diagnosis and holistic work-up and management of patients with lipodystrophy syndromes, which may improve outcomes for patients with this rare disease.

Combination of familial partial lipodystrophy (Dunnigan-Cobberling syndrome) with pulmonary sarcoidosis

Lipodystrophy syndromes are a heterogeneous group of extremely rare, inherited or acquired disorders that are characterized by total or partial fat loss or its improper redistribution. The prevalence of lipodystrophies is estimated to be 1:1,000,000 in the population, with approximately 1,000 cases currently described in the literature.Sarcoidosis is a multisystem disease of unknown etiology that is characterized by the formation of non-caseating epithelioid granulomas in the affected tissues. Despite the large number of studies, the etiology and pathogenesis of sarcoidosis still remain unknown. Most researchers allude to the possible autoimmune or immune-mediated genesis of the disease.This article presents a series of unique clinical cases of a combination of two rare diseases in one patient: sarcoidosis and familial partial lipodystrophy.

Comprehensive analysis of morbidity and mortality patterns in familial partial lipodystrophy patients: insights from a population study.

There is a lack of information on the clinical and molecular presentation of familial partial lipodystrophy (FPLD), a rare genetic disorder characterized by partial subcutaneous fat loss. This study aimed to provide a comprehensive assessment of the clinical, metabolic, and genetic features of FPLD in the Brazilian population. In a multicenter cross-sectional investigation we evaluated patients with FPLD across five Brazilian reference centers for lipodystrophies. Diagnosis of FPLD was made by clinical evaluation and genetic confirmation. Data on genetic, clinical, and metabolic characteristics were captured. Statistical analysis involved the utilization of the Kruskal-Wallis test to identify differences. The study included 106 patients with genetic confirmation of FPLD. The mean age was 44 ± 15 years, and they were predominantly female (78.3%). LMNA pathogenic variants were identified in 85.8% of patients, PPARG in 10.4%, PLIN1 in 2.8%, and MFN2 in 0.9%. Diabetes mellitus (DM) was highly prevalent (57.5%), affecting 54 females (50.9%). Median triglycerides levels were 199 mg/dL (54-2724 mg/dL), severe hypertriglyceridemia (≥ 500 mg/dL) was found in 34.9% and pancreatitis in 8.5%. Metabolic-associated fatty liver disease (MAFLD) was observed in 56.6%, and cardiovascular disease in 10.4%. The overall mortality rate was 3.8%, due to cardiovascular events. This study presents an extensive cohort of Brazilian patients with FPLD, predominantly DM with several multisystem complications. A comprehensive characterization of lipodystrophy syndromes is crucial for effective patient management and care.

Lipomatoses

Lipomatoses are benign proliferation of adipose tissue. Lipomas (benign fat tumors) are the most common component of lipomatosis. They may be unique or multiple, encapsulated or not, subcutaneous or sometimes visceral. In some cases, they form large areas of non-encapsulated fat hypertrophy, with a variable degree of fibrosis. They can develop despite the absence of obesity. They may be familial or acquired. At difference with lipodystrophy syndromes, they are not associated with lipoatrophy areas, except in some rare cases such as type 2 familial partial lipodystrophy syndromes (FPLD2). Their metabolic impact is variable in part depending on associated obesity. They may have functional or aesthetic consequences. Lipomatosis may be isolated, be part of a syndrome, or may be visceral. Isolated lipomatoses include multiple symmetrical lipomatosis (Madelung disease or Launois-Bensaude syndrome), familial multiple lipomatosis, the painful Dercum's disease also called Adiposis Dolorosa or Ander syndrome, mesosomatic lipomatosis also called Roch-Leri lipomatosis, familial angiolipomatosis, lipedema and hibernomas. Syndromic lipomatoses include PIK3CA-related disorders, Cowden/PTEN hamartomas-tumor syndrome, some lipodystrophy syndromes, and mitochondrial diseases, especially MERRF, multiple endocrine neoplasia type 1, neurofibromatosis type 1, Wilson disease, Pai or Haberland syndromes. Finally, visceral lipomatoses have been reported in numerous organs and sites: pancreatic, adrenal, abdominal, epidural, mediastinal, epicardial… The aim of this review is to present the main types of lipomatosis and their physiopathological component, when it is known.

Partial lipodystrophy: Clinical presentation and treatment

Lipodystrophic syndromes are acquired or genetic rare diseases, characterized by a generalized or partial lack of adipose tissue leading to metabolic alterations linked to strong insulin resistance. They are probably underdiagnosed, especially for partial forms. They are characterized by a lack of adipose tissue or a lack of adipose development leading to metabolic disorders associated with often severe insulin resistance, hypertriglyceridemia and hepatic steatosis. In partial forms of lipodystrophy, these mechanisms are aggravated by excess visceral adipose tissue and/or subcutaneous adipose tissue in the upper part of the body. Diagnosis is based on clinical examination, pathological context and comorbidities, and on results of metabolic investigations and genetic analyses, which together determine management and genetic counseling. Early lifestyle and dietary measures focusing on regular physical activity, and balanced diet avoiding excess energy intake are crucial. They are accompanied by multidisciplinary follow-up adapted to each clinical form. When standard treatments have failed to control metabolic disorders, the orphan drug metreleptin, an analog of leptin, can be effective in certain forms of lipodystrophy syndromes.

Primary disease of adipose tissue: When to think about and how to evaluate it in clinical practice?

Primary diseases of adipose tissue are rare disorders resulting from impairments in the physiological functions of adipose tissue (lipid stockage and endocrine function). It mainly refers to lipodystrophy syndromes with subcutaneous adipose tissue atrophy and/or altered body distribution of adipose tissue leading to insulin resistance, diabetes, hepatic steatosis, dyslipidemia, cardiovascular complications and polycystic ovary syndrome in women. Those syndromes are congenital or acquired, and lipoatrophy is partial or generalized. The diagnosis of lipodystrophy syndromes is often unrecognized, delayed and/or inaccurate, while it is of major importance to adapt investigations to search for specific comorbidities, in particular cardiovascular involvement, and set up multidisciplinary care, and in some cases specific treatment. Physicians have to recognize the clinical and biological elements allowing to establish the diagnosis. Lipodystrophic syndromes should be considered, notably, in patients with diabetes at a young age, with a normal or low BMI, negative pancreatic autoantibodies, presenting clinical signs of lipodystrophy and insulin resistance (acanthosis nigricans, hyperandrogenism, hepatic steatosis, high insulin doses). The association of diabetes and a family history of severe and/or early cardiovascular disease (coronary atherosclerosis, cardiomyopathy with rhythm and/or conduction disorders) may reveal Dunnigan syndrome, the most frequent form of familial lipodystrophy, due to LMNA pathogenic variants. Clinical assessment is primarily done through clinical examination: acanthosis nigricans, abnormal adipose tissue distribution, lipoatrophy, muscular hypertrophy, acromegaloid or Cushingoid features, lipomas, highly visible subcutaneous veins, may be revealing signs. The amount of circulating adipokines may reflect of adipose dysfunction with low leptinemia and adiponectinemia. Other biological metabolic parameters (hypertriglyceridemia, hyperinsulinemia, increased glycemia and hepatic enzymes) may also represent markers of insulin resistance. Quantification of total body fat by impedancemetry or dual-photon X-ray absorptiometry (DEXA) reveals decreased total body mass, in correlation with adipose tissue atrophy; metabolic magnetic resonance imaging can also quantify intraperitoneal and abdominal fat and the degree of hepatic steatosis. Histological analysis of adipose tissue showing structural abnormalities should be reserved for clinical research. Acquired lipodystrophic syndromes most often lead to similar clinical phenotype as congenital syndromes with generalized or partial lipoatrophy. The most frequent causes are old anti-HIV therapy or glucocorticoid treatments. Family history, history of treatments and clinical examination, including a careful physical examination, are keys for diagnosis.

Leptin replacement therapy in the management of lipodystrophy syndromes

Lipodystrophy syndromes are rare diseases of genetic or acquired origin, characterized by quantitative and qualitative defects in adipose tissue. The metabolic consequences of lipodystrophy syndromes, such as insulin resistant diabetes, hypertriglyceridemia and hepatic steatosis, are frequently very difficult to treat, resulting in significant risks of acute and/or chronic complications and of decreased quality of life. The production of leptin by lipodystrophic adipose tissue is decreased, more severely in generalized forms of lipodystrophy, where adipose tissue is absent from almost all body fat depots, than in partial forms of the disease, where lipoatrophy affects only some parts of the body and can be associated with increased body fat in other anatomical regions. Several lines of evidence in preclinical and clinical models have shown that leptin replacement therapy could improve the metabolic complications of lipodystrophy syndromes. Metreleptin, a recombinant leptin analogue, was approved as an orphan drug to treat the metabolic complications of leptin deficiency in patients with generalized lipodystrophy in the USA or with either generalized or partial lipodystrophy in Japan and Europe. In this brief review, we will discuss the benefits and limitations of this therapy, and the new expectations arising from the recent development of a therapeutic monoclonal antibody able to activate the leptin receptor.

PPA1 promotes adipogenesis by regulating the stability of C/EBPs.

Adipogenesis significantly contributes to healthy adipose tissue expansion in obesity. Increasing adipocyte number or function to alleviate adipose tissue overload could serve as a therapeutic strategy for both lipodystrophy and obesity-related metabolic syndrome. Inorganic pyrophosphatase (PPA1) is an enzyme that catalyzes the hydrolysis of pyrophosphate (PPi) and is involved in many biochemical reactions, but its function in adipose tissue has not been studied previously. In this study, we demonstrated that adipose-specific PPA1 knockout (PPA1AKO) mice showed lipodystrophy and spontaneously developed hepatic steatosis and severe insulin resistance under normal chow diet feeding. PPA1 deficiency suppressed the differentiation of primary adipocyte precursors and 3T3-L1 cells. Notably, PPA1 overexpression can restore inhibited adipogenesis in preadipocytes isolated from db/db mice and type 2 diabetes patients. Mechanistic studies have revealed that PPA1 acts as a positive regulator of early adipocyte differentiation by promoting CCAAT/enhancer-binding proteinβ and δ (C/EBPβ and δ) protein stability. Moreover, the function of PPA1 in adipogenesis is independent of its PPi catalytic activity. Collectively, our in vivo and in vitro findings demonstrated that PPA1 is a novel critical upstream regulator of adipogenesis, controlling adipose tissue development and whole-body metabolic homeostasis.

Comparison of metabolic and immunological profile of 2 types of familial partial lipodystrophy syndromes (PLIN1 and LMNA)

Comparison of metabolic and immunological profile of 2 types of familial partial lipodystrophy syndromes (PLIN1 and LMNA)