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Zhong ZX, Harris J, Wilber E, Gorman S, Savage DB, O'Rahilly S, Stears A, Williams RM. Describing the natural history of clinical, biochemical and radiological outcomes of children with familial partial lipodystrophy type 2 (FPLD2) from the United Kingdom: A retrospective case series. Clin Endocrinol (Oxf) 2022; 97:755-762. [PMID: 35920656 PMCID: PMC9804585 DOI: 10.1111/cen.14806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/10/2022] [Accepted: 07/12/2022] [Indexed: 01/07/2023]
Abstract
CONTEXT Familial partial lipodystrophy type 2 (FPLD2) results from autosomal dominant mutations in the LMNA gene, causing lack of subcutaneous fat deposition and excess ectopic fat accumulation, leading to metabolic complications and reduced life expectancy. The rarity of the condition means that the natural history of FPLD2 throughout childhood is not well understood. We report outcomes in a cohort of 12 (5M) children with a genetic diagnosis of FPLD2, under the care of the UK National Severe Insulin Resistance Service (NSIRS) which offers multidisciplinary input including dietetic, in addition to screening for comorbidities. OBJECTIVE To describe the natural history of clinical, biochemical and radiological outcomes of children with FPLD2. DESIGN A retrospective case note review of children with a genetic diagnosis of FPLD2 who had been seen in the paediatric NSIRS was performed. PATIENTS Twelve (5M) individuals diagnosed with FPLD2 via genetic testing before age 18 and who attended the NSIRS clinic were included. MEASUREMENTS Relationships between metabolic variables (HbA1c, triglycerides, fasting insulin, fasting glucose and alanine transaminase [ALT]) across time, from first visit to most recent, were explored using a multivariate model, adjusted for age and gender. The age of development of comorbidities was recorded. RESULTS Three patients (all female) developed diabetes between 12 and 19 years and were treated with Metformin. One female has hypertrophic cardiomyopathy and four (1M) patients developed mild hepatic steatosis at a median [range] age of 14(12-15) years. Three (1M) patients reported mental health problems related to lipodystrophy. There was no relationship between biochemical results and age. Patients with diabetes had higher concentrations of ALT than patients who did not have diabetes, adjusted for age, gender and body mass index standard deviation scores. CONCLUSIONS Despite dietetic input, some patients, more commonly females, developed comorbidities after the age of 10. The absence of relationships between biochemical results and age likely reflects a small cohort size. We propose that, while clinical review and dietetic support are beneficial for children with FPLD2, formal screening for comorbidities before age 10 may not be of benefit. Clinical input from an multidisciplinary team including dietician, psychologist and clinician should be offered after diagnosis.
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Affiliation(s)
| | | | - Ellen Wilber
- Cambridge University Hospitals NHS TrustCambridgeUK
| | | | - David B. Savage
- Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
| | | | - Anna Stears
- Cambridge University Hospitals NHS TrustCambridgeUK
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Vasandani C, Li X, Sekizkardes H, Brown RJ, Garg A. Phenotypic Differences Among Familial Partial Lipodystrophy Due to LMNA or PPARG Variants. J Endocr Soc 2022; 6:bvac155. [PMID: 36397776 PMCID: PMC9664976 DOI: 10.1210/jendso/bvac155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Indexed: 11/19/2022] Open
Abstract
Context Despite several reports of familial partial lipodystrophy (FPLD) type 2 (FPLD2) due to heterozygous LMNA variants and FPLD3 due to PPARG variants, the phenotypic differences among them remain unclear. Objective To compare the body fat distribution, metabolic parameters, and prevalence of metabolic complications between FPLD3 and FPLD2. Methods A retrospective, cross-sectional comparison of patients from 2 tertiary referral centers-UT Southwestern Medical Center and the National Institute of Diabetes and Digestive and Kidney Diseases. A total of 196 females and 59 males with FPLD2 (age 2-86 years) and 28 females and 4 males with FPLD3 (age 9-72 years) were included. The main outcome measures were skinfold thickness, regional body fat by dual-energy X-ray absorptiometry (DXA), metabolic variables, and prevalence of diabetes mellitus and hypertriglyceridemia. Results Compared with subjects with FPLD2, subjects with FPLD3 had significantly increased prevalence of hypertriglyceridemia (66% vs 84%) and diabetes (44% vs 72%); and had higher median fasting serum triglycerides (208 vs 255 mg/dL), and mean hemoglobin A1c (6.4% vs 7.5%). Compared with subjects with FPLD2, subjects with FPLD3 also had significantly higher mean upper limb fat (21% vs 27%) and lower limb fat (16% vs 21%) on DXA and increased median skinfold thickness at the anterior thigh (5.8 vs 11.3 mm), calf (4 vs 6 mm), triceps (5.5 vs 7.5 mm), and biceps (4.3 vs 6.8 mm). Conclusion Compared with subjects with FPLD2, subjects with FPLD3 have milder lipodystrophy but develop more severe metabolic complications, suggesting that the remaining adipose tissue in subjects with FPLD3 may be dysfunctional or those with mild metabolic disease are underrecognized.
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Affiliation(s)
- Chandna Vasandani
- Division of Nutrition and Metabolic Diseases and the Center for Human Nutrition, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Xilong Li
- Department of Population and Data Sciences, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Hilal Sekizkardes
- National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Rebecca J Brown
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Abhimanyu Garg
- Division of Nutrition and Metabolic Diseases and the Center for Human Nutrition, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX 75390, USA
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Abstract
INTRODUCTION Primary chylomicronemia is characterized by pathological accumulation of chylomicrons in the plasma causing severe hypertriglyceridemia, typically >10 mmol/L (>875 mg/dL). Patients with the ultra-rare familial chylomicronemia syndrome (FCS) subtype completely lack lipolytic capacity and respond minimally to traditional triglyceride-lowering therapies. The mainstay of treatment is a low-fat diet, which is difficult to follow and compromises quality of life. New therapies are being developed primarily to prevent episodes of life-threatening acute pancreatitis. AREAS COVERED Antagonists of apolipoprotein (apo) C-III, such as the antisense oligonucleotide (ASO) volanesorsen, significantly reduce triglyceride levels in chylomicronemia. However, approval of and access to volanesorsen are restricted since a substantial proportion of treated FCS patients developed thrombocytopenia. Newer apo C-III antagonists, namely, the ASO olezarsen (formerly AKCEA-APOCIII-LRx) and short interfering RNA (siRNA) ARO-APOC3, appear to show efficacy with less risk of thrombocytopenia. Potential utility of antagonists of angiopoietin-like protein 3 (ANGPTL3) such as evinacumab and the siRNA ARO-ANG3 in subtypes of chylomicronemia remains to be defined. EXPERT OPINION Emerging pharmacologic therapies for chylomicronemia show promise, particularly apo C-III antagonists. However, these treatments are still investigational. Further study of their efficacy and safety in patients with both rare FCS and more common multifactorial chylomicronemia is needed.
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Affiliation(s)
- Isabel Shamsudeen
- Department of Medicine, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Robert A Hegele
- Department of Medicine, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
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Rutkowska L, Salachna D, Lewandowski K, Lewiński A, Gach A. Familial Partial Lipodystrophy-Literature Review and Report of a Novel Variant in PPARG Expanding the Spectrum of Disease-Causing Alterations in FPLD3. Diagnostics (Basel) 2022; 12:1122. [PMID: 35626278 PMCID: PMC9139680 DOI: 10.3390/diagnostics12051122] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/25/2022] [Accepted: 04/28/2022] [Indexed: 11/16/2022] Open
Abstract
Familial partial lipodystrophy (FPLD) is a rare genetic disorder characterized by the selective loss of adipose tissue. Its estimated prevalence is as low as 1 in 1 million. The deficiency of metabolically active adipose tissue is closely linked with a wide range of metabolic complications, such as insulin resistance, lipoatrophic diabetes, dyslipidemia with severe hypertriglyceridemia, hypertension or hepatic steatosis. Moreover, female patients often develop hyperandrogenism, hirsutism, polycystic ovaries and infertility. The two most common types are FPLD type 2 and 3. Variants within LMNA and PPARG genes account for more than 50% of all reported FPLD cases. Because of its high heterogeneity and rarity, lipodystrophy can be easily unrecognized or misdiagnosed. To determine the genetic background of FPLD in a symptomatic woman and her close family, an NGS custom panel was used to sequence LMNA and PPARG genes. The affected patient presented fat deposits in the face, neck and trunk, with fat loss combined with muscular hypertrophy in the lower extremities and hirsutism, all features first manifesting at puberty. Her clinical presentation included metabolic disturbances, including hypercholesterolemia with severe hypertriglyceridemia, diabetes mellitus and hepatic steatosis. This together with her typical fat distribution and physical features raised a suspicion of FPLD. NGS analysis revealed the presence of missense heterozygous variant c.443G>A in exon 4 of PPARG gene, causing glycine to glutamic acid substitution at amino acid position 148, p.(Gly148Glu). The variant was also found in the patient’s mother and son. The variant was not previously reported in any public database. Based on computational analysis, crucial variant localization within DNA-binding domain of PPARγ, available literature data and the variant cosegregation in the patient’s family, novel c.443G>A variant was suspected to be causative. Functional testing is needed to confirm the pathogenicity of the novel variant. Inherited lipodystrophy syndromes represent a heterogenous group of metabolic disorders, whose background often remains unclear. A better understating of the genetic basis would allow earlier diagnosis and targeted treatment implementation.
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Affiliation(s)
- Lena Rutkowska
- Department of Genetics, Polish Mother’s Memorial Hospital-Research Institute, 93-338 Lodz, Poland;
| | - Dominik Salachna
- Department of Genetics, Polish Mother’s Memorial Hospital-Research Institute, 93-338 Lodz, Poland;
| | - Krzysztof Lewandowski
- Department of Endocrinology and Metabolic Diseases, Medical University of Lodz, 90-419 Lodz, Poland
- Department of Endocrinology and Metabolic Diseases, Polish Mother’s Memorial Hospital-Research Institute, 93-338 Lodz, Poland
| | - Andrzej Lewiński
- Department of Endocrinology and Metabolic Diseases, Medical University of Lodz, 90-419 Lodz, Poland
- Department of Endocrinology and Metabolic Diseases, Polish Mother’s Memorial Hospital-Research Institute, 93-338 Lodz, Poland
| | - Agnieszka Gach
- Department of Genetics, Polish Mother’s Memorial Hospital-Research Institute, 93-338 Lodz, Poland;
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Abstract
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.
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Affiliation(s)
- Isabel Shamsudeen
- Department of Medicine, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
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Role of Actionable Genes in Pursuing a True Approach of Precision Medicine in Monogenic Diabetes. Genes (Basel) 2022; 13:genes13010117. [PMID: 35052457 PMCID: PMC8774614 DOI: 10.3390/genes13010117] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/04/2022] [Accepted: 01/05/2022] [Indexed: 12/16/2022] Open
Abstract
Monogenic diabetes is a genetic disorder caused by one or more variations in a single gene. It encompasses a broad spectrum of heterogeneous conditions, including neonatal diabetes, maturity onset diabetes of the young (MODY) and syndromic diabetes, affecting 1-5% of patients with diabetes. Some of these variants are harbored by genes whose altered function can be tackled by specific actions ("actionable genes"). In suspected patients, molecular diagnosis allows the implementation of effective approaches of precision medicine so as to allow individual interventions aimed to prevent, mitigate or delay clinical outcomes. This review will almost exclusively concentrate on the clinical strategy that can be specifically pursued in carriers of mutations in "actionable genes", including ABCC8, KCNJ11, GCK, HNF1A, HNF4A, HNF1B, PPARG, GATA4 and GATA6. For each of them we will provide a short background on what is known about gene function and dysfunction. Then, we will discuss how the identification of their mutations in individuals with this form of diabetes, can be used in daily clinical practice to implement specific monitoring and treatments. We hope this article will help clinical diabetologists carefully consider who of their patients deserves timely genetic testing for monogenic diabetes.
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Lamin A/C missense variants: from discovery to functional validation. NPJ Genom Med 2021; 6:102. [PMID: 34862397 PMCID: PMC8642461 DOI: 10.1038/s41525-021-00266-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 10/28/2021] [Indexed: 01/09/2023] Open
Abstract
Rare variants in the LMNA gene encoding nuclear lamin A/C are causal for more than a dozen diverse mendelian disorders. Defining the functional consequences of LMNA variants has been challenging given the pleiotropy of gene functions and potential pathogenic mechanisms. It is essential to develop trustworthy, scalable and rapidly deployable in vitro assays of function to enable timely assessment of missense variants that are being uncovered by high throughout next-generation sequencing.
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Lazarte J, Wang J, McIntyre AD, Hegele RA. Prevalence of severe hypertriglyceridemia and pancreatitis in familial partial lipodystrophy type 2. J Clin Lipidol 2021; 15:653-657. [PMID: 34340952 DOI: 10.1016/j.jacl.2021.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 07/09/2021] [Accepted: 07/12/2021] [Indexed: 10/20/2022]
Abstract
Familial partial lipodystrophy (FPLD) is a rare Mendelian condition listed in the differential diagnosis of severe hypertriglyceridemia (HTG) and pancreatitis. Here we determined the prevalence of severe HTG and pancreatitis among a cohort of 74 FPLD patients assessed in a lipid clinic. We studied lipid profiles from individuals with either of the two most common pathogenic monoallelic variants in LMNA, namely p.R482Q (N= 51) and p.R482W (N= 23). In total, 28 (37.8%) patients with a mean age of 41.8 ± 14.8 years had diabetes, while 46 (62.2%) patients with a mean age of 35.4 ± 19.4 years had no diabetes. Among patients with and without diabetes, median TG levels (interquartile range) were 2.73 (4.78) and 1.86 (1.66) mmol/L (242 [423] and 165 [147] mg/dL), respectively. Overall, 4 subjects (5.4%) had triglyceride levels > 10 mmol/L (> 885 mg/dL), of whom 3 (4.1%) had a history of hospitalization for acute pancreatitis. All 4 patients with severe HTG had diabetes, i.e. 14.3% of those with diabetes. In contrast, FPLD2 patients without diabetes had only mild HTG, with no instances of severe HTG or pancreatitis. Thus, among this selected lipid clinic cohort with lipodystrophy, severe HTG and pancreatitis in FPLD2 are relatively common when diabetes is present.
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Affiliation(s)
- Julieta Lazarte
- Departments of Medicine and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Jian Wang
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Adam D McIntyre
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Robert A Hegele
- Departments of Medicine and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada.
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Lazarte J, Hegele RA. Pediatric Dyslipidemia-Beyond Familial Hypercholesterolemia. Can J Cardiol 2020; 36:1362-1371. [PMID: 32640212 DOI: 10.1016/j.cjca.2020.03.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 03/04/2020] [Accepted: 03/16/2020] [Indexed: 12/17/2022] Open
Abstract
Dyslipidemia is seen with increasing prevalence in young Canadians, mainly mild to moderate hypertriglyceridemia secondary to obesity. This review focuses on pediatric dyslipidemias excluding familial hypercholesterolemia (FH), but including both severe and mild to moderate hypertriglyceridemia, combined hyperlipidemia, and elevated lipoprotein(a) [Lp(a)]. We suggest that for Canadian children and adolescents with dyslipidemia, atherosclerotic cardiovascular disease (ASCVD) risk assessment should include both low-density lipoprotein cholesterol and triglyceride measurement. To further stratify risk, determination of non-high-density lipoprotein cholesterol is recommended, for both its ability to predict ASCVD and convenience for the patient because fasting is not required. Similarly, apolipoprotein B measurement (fasting or nonfasting), where available, can be helpful. Lp(a) measurement should not be routine in childhood, but it can be considered in special circumstances. After ruling out secondary causes, the foundation for management of pediatric dyslipidemia includes weight regulation, optimizing diet, and increasing activity level. At present, randomized clinical trial data to guide pharmaceutical management of pediatric hypertriglyceridemia or other non-FH pediatric dyslipidemias are scarce. Pharmaceutical management should be reserved for special situations in which risk of complications such as acute pancreatitis or ASCVD over the intermediate term is high and conservative lifestyle-based interventions have been ineffective.
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Affiliation(s)
- Julieta Lazarte
- Departments of Medicine and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Robert A Hegele
- Departments of Medicine and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada.
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Bruder-Nascimento T, Kress TC, Belin de Chantemele EJ. Recent advances in understanding lipodystrophy: a focus on lipodystrophy-associated cardiovascular disease and potential effects of leptin therapy on cardiovascular function. F1000Res 2019; 8:F1000 Faculty Rev-1756. [PMID: 31656583 PMCID: PMC6798323 DOI: 10.12688/f1000research.20150.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/08/2019] [Indexed: 01/09/2023] Open
Abstract
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.
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Affiliation(s)
- Thiago Bruder-Nascimento
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA, USA
- Department of Pediatrics, Division of Endocrinology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Taylor C. Kress
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Eric J. Belin de Chantemele
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA, USA
- Department of Medicine, Section of Cardiology, Medical College of Georgia at Augusta University, Augusta, GA, USA
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Friesen M, Cowan CA. Adipocyte Metabolism and Insulin Signaling Perturbations: Insights from Genetics. Trends Endocrinol Metab 2019; 30:396-406. [PMID: 31072658 DOI: 10.1016/j.tem.2019.03.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 03/12/2019] [Accepted: 03/22/2019] [Indexed: 01/27/2023]
Abstract
Insulin resistance (IR) is a rapidly growing pandemic. It poses an enormous health burden given its comorbidity with obesity, type 2 diabetes (T2D), and other metabolic and cardiovascular diseases (CVDs). Adipose tissue has been established as a key regulator of whole-body metabolic homeostasis, with interest growing rapidly. Emerging evidence suggests that adipocytes play an important role in these afflictions and contribute to IR. Genome-wide association studies (GWAS) have begun to illuminate the genetics underlying obesity, T2D, and IR, and this will allow further study into the disease mechanisms of the genes implicated in these metabolic diseases. Progress towards understanding the molecular mechanisms underlying diseased adipocytes will be discussed here, with an eye towards the future in developing novel therapeutics to combat metabolic disease.
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Affiliation(s)
- Max Friesen
- Division of Cardiovascular Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA; Department of Anatomy and Embryology, Leiden University Medical Center, 2300 RC, Leiden, The Netherlands; Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA
| | - Chad A Cowan
- Division of Cardiovascular Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA.
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Broekema M, Savage D, Monajemi H, Kalkhoven E. Gene-gene and gene-environment interactions in lipodystrophy: Lessons learned from natural PPARγ mutants. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:715-732. [DOI: 10.1016/j.bbalip.2019.02.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 01/13/2019] [Accepted: 02/02/2019] [Indexed: 12/13/2022]
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Elias CP, Antunes DE, Coelho MS, de Lima CL, Rassi N, de Melo APM, Amato AA. Evaluation of the hypothalamic-pituitary-adrenal axis in a case series of familial partial lipodystrophy. Diabetol Metab Syndr 2019; 11:1. [PMID: 30622652 PMCID: PMC6317180 DOI: 10.1186/s13098-018-0396-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Accepted: 12/20/2018] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Familial partial lipodystrophy (FPL) is a rare genetic disease characterized by body fat abnormalities that lead to insulin resistance (IR). Clinical conditions linked to milder IR, such as type 2 diabetes (T2D) and metabolic syndrome, are associated with abnormalities of the hypothalamic-pituitary-adrenal (HPA) axis, but little is known about its activity in FPL. METHODS Patients meeting the clinical criteria for FPL were subjected to anthropometric, biochemical and hormone analyses. A genetic study to identify mutations in the genes encoding peroxisome proliferator-activated receptor gamma (PPARγ) was performed. Polycystic ovary syndrome and hepatic steatosis were investigated, and the patient body compositions were analyzed via dual X-ray energy absorptiometry (DXA). The HPA axis was assessed via basal [cortisol, adrenocorticotrophic hormone (ACTH), cortisol binding globulin, nocturnal salivary cortisol and urinary free cortisol (UFC)] as well as dynamic suppression tests (cortisol post 0.5 mg and post 1 mg dexamethasone). RESULTS Six patients (five female and one male) aged 17 to 42 years were included. In DXA analyses, the fat mass ratio between the trunk and lower limbs (FMR) was > 1.2 in all phenotypes. One patient had a confirmed mutation in the PPARγ gene: a novel heterozygous substitution of p. Arg 212 Trp (c.634C>T) at exon 5. HPA sensitivity to glucocorticoid feedback was preserved in all six patients, and a trend towards lower basal serum cortisol, serum ACTH and UFC values was observed. CONCLUSIONS Our findings suggest that FPL is not associated with overt abnormalities in the HPA axis, despite a trend towards low-normal basal cortisol and ACTH values and lower UFC levels. These findings suggest that the extreme insulin resistance occurring in FPL may lead to a decrease in HPA axis activity without changing its sensitivity to glucocorticoid feedback, in contrast to the abnormalities in HPA axis function in T2D and common metabolic syndrome.
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Affiliation(s)
- Cecília Pacheco Elias
- Unit of Endocrinology, Hospital Alberto Rassi–General Hospital of Goiânia (HGG), Avenida Anhanguera, 6479 - St. Oeste, Goiânia, GO CEP 74120-080 Brazil
| | | | - Michella Soares Coelho
- Laboratory of Molecular Pharmacology, School of Health Sciences, University of Brasília (UnB), Brasília, Brazil
| | - Caroline Lourenço de Lima
- Laboratory of Molecular Pharmacology, School of Health Sciences, University of Brasília (UnB), Brasília, Brazil
| | - Nelson Rassi
- Unit of Endocrinology, Hospital Alberto Rassi–General Hospital of Goiânia (HGG), Avenida Anhanguera, 6479 - St. Oeste, Goiânia, GO CEP 74120-080 Brazil
| | | | - Angélica Amorim Amato
- Laboratory of Molecular Pharmacology, School of Health Sciences, University of Brasília (UnB), Brasília, Brazil
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Akinci B, Meral R, Oral EA. Phenotypic and Genetic Characteristics of Lipodystrophy: Pathophysiology, Metabolic Abnormalities, and Comorbidities. Curr Diab Rep 2018; 18:143. [PMID: 30406415 DOI: 10.1007/s11892-018-1099-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE OF REVIEW This article focuses on recent progress in understanding the genetics of lipodystrophy syndromes, the pathophysiology of severe metabolic abnormalities caused by these syndromes, and causes of severe morbidity and a possible signal of increased mortality associated with lipodystrophy. An updated classification scheme is also presented. RECENT FINDINGS Lipodystrophy encompasses a group of heterogeneous rare diseases characterized by generalized or partial lack of adipose tissue and associated metabolic abnormalities including altered lipid metabolism and insulin resistance. Recent advances in the field have led to the discovery of new genes associated with lipodystrophy and have also improved our understanding of adipose biology, including differentiation, lipid droplet assembly, and metabolism. Several registries have documented the natural history of the disease and the serious comorbidities that patients with lipodystrophy face. There is also evolving evidence for increased mortality rates associated with lipodystrophy. Lipodystrophy syndromes represent a challenging cluster of diseases that lead to severe insulin resistance, a myriad of metabolic abnormalities, and serious morbidity. The understanding of these syndromes is evolving in parallel with the identification of novel disease-causing mechanisms.
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Affiliation(s)
- Baris Akinci
- Brehm Center for Diabetes Research, Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan, 1000 Wall Street, Room 5313, Ann Arbor, MI, 48105, USA
- Division of Endocrinology, Department of Internal Medicine, Dokuz Eylul University, Izmir, Turkey
| | - Rasimcan Meral
- Brehm Center for Diabetes Research, Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan, 1000 Wall Street, Room 5313, Ann Arbor, MI, 48105, USA
| | - Elif Arioglu Oral
- Brehm Center for Diabetes Research, Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan, 1000 Wall Street, Room 5313, Ann Arbor, MI, 48105, USA.
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15
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Ho R, Hegele RA. Complex effects of laminopathy mutations on nuclear structure and function. Clin Genet 2018; 95:199-209. [DOI: 10.1111/cge.13455] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/26/2018] [Accepted: 09/27/2018] [Indexed: 12/12/2022]
Affiliation(s)
- Rosettia Ho
- Departments of Biochemistry and Medicine, and Robarts Research Institute; Schulich School of Medicine and Dentistry, Western University; London Ontario Canada
| | - Robert A. Hegele
- Departments of Biochemistry and Medicine, and Robarts Research Institute; Schulich School of Medicine and Dentistry, Western University; London Ontario Canada
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16
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Yeh YS, Jheng HF, Iwase M, Kim M, Mohri S, Kwon J, Kawarasaki S, Li Y, Takahashi H, Ara T, Nomura W, Kawada T, Goto T. The Mevalonate Pathway Is Indispensable for Adipocyte Survival. iScience 2018; 9:175-191. [PMID: 30396151 DOI: 10.1016/j.isci.2018.10.019] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 09/26/2018] [Accepted: 10/16/2018] [Indexed: 01/20/2023] Open
Abstract
The mevalonate pathway is essential for the synthesis of isoprenoids and cholesterol. Adipose tissue is known as a major site for cholesterol storage; however, the role of the local mevalonate pathway and its synthesized isoprenoids remains unclear. In this study, adipose-specific mevalonate pathway-disrupted (aKO) mice were generated through knockout of 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase (HMGCR). aKO mice showed serious lipodystrophy accompanied with glucose and lipid metabolic disorders and hepatomegaly. These metabolic variations in aKO mice were dramatically reversed after fat transplantation. In addition, HMGCR-disrupted adipocytes exhibited loss of lipid accumulation and an increase of cell death, which were ameliorated by the supplementation of mevalonate and geranylgeranyl pyrophosphate but not farnesyl pyrophosphate and squalene. Finally, we found that apoptosis may be involved in adipocyte death induced by HMGCR down-regulation. Our findings indicate that the mevalonate pathway is essential for adipocytes and further suggest that this pathway is an important regulator of adipocyte turnover.
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Affiliation(s)
- Yu-Sheng Yeh
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan
| | - Huei-Fen Jheng
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan
| | - Mari Iwase
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan
| | - Minji Kim
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan
| | - Shinsuke Mohri
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan
| | - Jungin Kwon
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan
| | - Satoko Kawarasaki
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan
| | - Yongjia Li
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan
| | - Haruya Takahashi
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan
| | - Takeshi Ara
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan
| | - Wataru Nomura
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan; Research Unit for Physiological Chemistry, Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Kyoto, Japan
| | - Teruo Kawada
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan; Research Unit for Physiological Chemistry, Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Kyoto, Japan
| | - Tsuyoshi Goto
- Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan; Research Unit for Physiological Chemistry, Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Kyoto, Japan.
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17
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Ernszt D, Banfai K, Kellermayer Z, Pap A, Lord JM, Pongracz JE, Kvell K. PPARgamma Deficiency Counteracts Thymic Senescence. Front Immunol 2017; 8:1515. [PMID: 29163553 PMCID: PMC5681731 DOI: 10.3389/fimmu.2017.01515] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 10/26/2017] [Indexed: 12/30/2022] Open
Abstract
Thymic senescence contributes to increased incidence of infection, cancer and autoimmunity at senior ages. This process manifests as adipose involution. As with other adipose tissues, thymic adipose involution is also controlled by PPARgamma. This is supported by observations reporting that systemic PPARgamma activation accelerates thymic adipose involution. Therefore, we hypothesized that decreased PPARgamma activity could prevent thymic adipose involution, although it may trigger metabolic adverse effects. We have confirmed that both human and murine thymic sections show marked staining for PPARgamma at senior ages. We have also tested the thymic lobes of PPARgamma haplo-insufficient and null mice. Supporting our working hypothesis both adult PPARgamma haplo-insufficient and null mice show delayed thymic senescence by thymus histology, thymocyte mouse T-cell recombination excision circle qPCR and peripheral blood naive T-cell ratio by flow-cytometry. Delayed senescence showed dose-response with respect to PPARgamma deficiency. Functional immune parameters were also evaluated at senior ages in PPARgamma haplo-insufficient mice (null mice do not reach senior ages due to metabolic adverse affects). As expected, sustained and elevated T-cell production conferred oral tolerance and enhanced vaccination efficiency in senior PPARgamma haplo-insufficient, but not in senior wild-type littermates according to ELISA IgG measurements. Of note, humans also show increased oral intolerance issues and decreased protection by vaccines at senior ages. Moreover, PPARgamma haplo-insufficiency also exists in human known as a rare disease (FPLD3) causing metabolic adverse effects, similar to the mouse. When compared to age- and metabolic disorder-matched other patient samples (FPLD2 not affecting PPARgamma activity), FPLD3 patients showed increased human Trec (hTrec) values by qPCR (within healthy human range) suggesting delayed thymic senescence, in accordance with mouse results and supporting our working hypothesis. In summary, our experiments prove that systemic decrease of PPARgamma activity prevents thymic senescence, albeit with metabolic drawbacks. However, thymic tissue-specific PPARgamma antagonism would likely solve the issue.
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Affiliation(s)
- David Ernszt
- Faculty of Pharmacy, Department of Pharmaceutical Biotechnology, University of Pecs, Pecs, Hungary.,Szentagothai Research Center, University of Pecs, Pecs, Hungary
| | - Krisztina Banfai
- Faculty of Pharmacy, Department of Pharmaceutical Biotechnology, University of Pecs, Pecs, Hungary.,Szentagothai Research Center, University of Pecs, Pecs, Hungary
| | - Zoltan Kellermayer
- Faculty of Medicine, Department of Immunology and Biotechnology, University of Pecs, Pecs, Hungary
| | - Attila Pap
- Faculty of Medicine, Department of Biochemistry and Molecular Biology, University of Debrecen, Debrecen, Hungary
| | - Janet M Lord
- College of Medical and Dental Sciences, Institute of Inflammation and Aging, University of Birmingham, Birmingham, United Kingdom
| | - Judit E Pongracz
- Faculty of Pharmacy, Department of Pharmaceutical Biotechnology, University of Pecs, Pecs, Hungary.,Szentagothai Research Center, University of Pecs, Pecs, Hungary
| | - Krisztian Kvell
- Faculty of Pharmacy, Department of Pharmaceutical Biotechnology, University of Pecs, Pecs, Hungary.,Szentagothai Research Center, University of Pecs, Pecs, Hungary
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18
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Charó NL, Rodríguez Ceschan MI, Galigniana NM, Toneatto J, Piwien-Pilipuk G. Organization of nuclear architecture during adipocyte differentiation. Nucleus 2017; 7:249-69. [PMID: 27416359 DOI: 10.1080/19491034.2016.1197442] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Obesity is a serious health problem worldwide since it is a major risk factor for chronic diseases such as type II diabetes. Obesity is the result of hyperplasia (associated with increased adipogenesis) and hypertrophy (associated with decreased adipogenesis) of the adipose tissue. Therefore, understanding the molecular mechanisms underlying the process of adipocyte differentiation is relevant to delineate new therapeutic strategies for treatment of obesity. As in all differentiation processes, temporal patterns of transcription are exquisitely controlled, allowing the acquisition and maintenance of the adipocyte phenotype. The genome is spatially organized; therefore decoding local features of the chromatin language alone does not suffice to understand how cell type-specific gene expression patterns are generated. Elucidating how nuclear architecture is built during the process of adipogenesis is thus an indispensable step to gain insight in how gene expression is regulated to achieve the adipocyte phenotype. Here we will summarize the recent advances in our understanding of the organization of nuclear architecture as progenitor cells differentiate in adipocytes, and the questions that still remained to be answered.
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Affiliation(s)
- Nancy L Charó
- a Laboratory of Nuclear Architecture, Instituto de Biología y Medicina Experimental (IByME) - CONICET , Buenos Aires , Argentina
| | - María I Rodríguez Ceschan
- a Laboratory of Nuclear Architecture, Instituto de Biología y Medicina Experimental (IByME) - CONICET , Buenos Aires , Argentina
| | - Natalia M Galigniana
- a Laboratory of Nuclear Architecture, Instituto de Biología y Medicina Experimental (IByME) - CONICET , Buenos Aires , Argentina
| | - Judith Toneatto
- a Laboratory of Nuclear Architecture, Instituto de Biología y Medicina Experimental (IByME) - CONICET , Buenos Aires , Argentina
| | - Graciela Piwien-Pilipuk
- a Laboratory of Nuclear Architecture, Instituto de Biología y Medicina Experimental (IByME) - CONICET , Buenos Aires , Argentina
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19
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Forte R, Pesce C, De Vito G, Boreham CAG. The Body Fat-Cognition Relationship in Healthy Older Individuals: Does Gynoid vs Android Distribution Matter? J Nutr Health Aging 2017; 21:284-291. [PMID: 28244568 DOI: 10.1007/s12603-016-0783-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
OBJECTIVE To examine the relationship between regional and whole body fat accumulation and core cognitive executive functions. DESIGN Cross-sectional study. SETTINGS AND PARTICIPANTS 78 healthy men and women aged between 65 and 75 years recruited through consumer's database. MEASUREMENTS DXA measured percentage total body fat, android, gynoid distribution and android/gynoid ratio; inhibition and working memory updating through Random Number Generation test and cognitive flexibility by Trail Making test. First-order partial correlations between regional body fat and cognitive executive function were computed partialling out the effects of whole body fat. Moderation analysis was performed to verify the effect of gender on the body fat-cognition relationship. RESULTS Results showed a differentiated pattern of fat-cognition relationship depending on fat localization and type of cognitive function. Statistically significant relationships were observed between working memory updating and: android fat (r = -0.232; p = 0.042), gynoid fat (r = 0.333; p = 0.003) and android/gynoid ratio (r = -0.272; p = 0.017). Separating genders, the only significant relationship was observed in females between working memory updating and gynoid fat (r = 0.280; p = 0.045). In spite of gender differences in both working memory updating and gynoid body fat levels, moderation analysis did not show an effect of gender on the relationship between gynoid fat and working memory updating. CONCLUSIONS Results suggest a protective effect of gynoid body fat and a deleterious effect of android body fat. Although excessive body fat increases the risk of developing CDV, metabolic and cognitive problems, maintaining a certain proportion of gynoid fat may help prevent cognitive decline, particularly in older women. Guidelines for optimal body composition maintenance for the elderly should not target indiscriminate weight loss, but weight maintenance through body fat/lean mass control based on non-pharmacological tools such as physical exercise, known to have protective effects against CVD risk factors and age-related cognitive deterioration.
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Affiliation(s)
- R Forte
- Roberta Forte Department of Human Health and Movement Sciences, University of Rome «Foro Italico», Roma 00135, Italy telephone +39 6 36733367 fax +39 6 36733362 e-mail:
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20
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Chan D, McIntyre AD, Hegele RA, Don-Wauchope AC. Familial partial lipodystrophy presenting as metabolic syndrome. J Clin Lipidol 2016; 10:1488-1491. [DOI: 10.1016/j.jacl.2016.08.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 08/16/2016] [Accepted: 08/19/2016] [Indexed: 12/20/2022]
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21
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Lee JH, Han JS, Kong J, Ji Y, Lv X, Lee J, Li P, Kim JB. Protein Kinase A Subunit Balance Regulates Lipid Metabolism in Caenorhabditis elegans and Mammalian Adipocytes. J Biol Chem 2016; 291:20315-28. [PMID: 27496951 DOI: 10.1074/jbc.m116.740464] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Indexed: 11/06/2022] Open
Abstract
Protein kinase A (PKA) is a cyclic AMP (cAMP)-dependent protein kinase composed of catalytic and regulatory subunits and involved in various physiological phenomena, including lipid metabolism. Here we demonstrated that the stoichiometric balance between catalytic and regulatory subunits is crucial for maintaining basal PKA activity and lipid homeostasis. To uncover the potential roles of each PKA subunit, Caenorhabditis elegans was used to investigate the effects of PKA subunit deficiency. In worms, suppression of PKA via RNAi resulted in severe phenotypes, including shortened life span, decreased egg laying, reduced locomotion, and altered lipid distribution. Similarly, in mammalian adipocytes, suppression of PKA regulatory subunits RIα and RIIβ via siRNAs potently stimulated PKA activity, leading to potentiated lipolysis without increasing cAMP levels. Nevertheless, insulin exerted anti-lipolytic effects and restored lipid droplet integrity by antagonizing PKA action. Together, these data implicate the importance of subunit stoichiometry as another regulatory mechanism of PKA activity and lipid metabolism.
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Affiliation(s)
- Jung Hyun Lee
- From the Department of Biological Sciences, Institute of Molecular Biology and Genetics, Seoul National University, 08862 Seoul, Korea
| | - Ji Seul Han
- From the Department of Biological Sciences, Institute of Molecular Biology and Genetics, Seoul National University, 08862 Seoul, Korea
| | - Jinuk Kong
- From the Department of Biological Sciences, Institute of Molecular Biology and Genetics, Seoul National University, 08862 Seoul, Korea
| | - Yul Ji
- From the Department of Biological Sciences, Institute of Molecular Biology and Genetics, Seoul National University, 08862 Seoul, Korea
| | - Xuchao Lv
- the MOE Key Laboratory of Bioinformatics and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China and
| | - Junho Lee
- From the Department of Biological Sciences, Institute of Molecular Biology and Genetics, Seoul National University, 08862 Seoul, Korea, the Department of Biophysics and Chemical Biology, Seoul National University, Seoul 08862, Korea
| | - Peng Li
- the MOE Key Laboratory of Bioinformatics and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China and
| | - Jae Bum Kim
- From the Department of Biological Sciences, Institute of Molecular Biology and Genetics, Seoul National University, 08862 Seoul, Korea,
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22
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Marcos-Alonso S, Bautista-Hernandez V, Portela Torrón F. Successful cardiac transplantation in a patient with congenital generalized lipodystrophy. Pediatr Transplant 2016; 20:321-4. [PMID: 26821845 DOI: 10.1111/petr.12656] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/16/2015] [Indexed: 11/30/2022]
Abstract
We report a case of a 12-yr-old boy referred to our unit with congenital generalized lipodystrophy and dilated cardiomyopathy related to a lamin gene mutation. He progressively developed end-stage heart failure and was referred for heart transplant evaluation. The patient's lipid profile, glucose level, and renal function were normal, and vascular retinopathy was ruled out. He underwent orthotopic bicaval HT and had an uneventful recovery. He was discharged home two wk after surgery with good graft function. During follow-up, he developed hyperglycemia and dyslipidemia, which were controlled by increasing leptin dose and starting oral antidiabetic drugs. The patient is currently doing well two yr after transplantation.
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Affiliation(s)
- Sonia Marcos-Alonso
- Congenital Heart Diseases and Pediatric Cardiology Unit, Pediatric Department, Hospital Materno Infantil, Complejo Hospitalario Universitario A Coruña, A Coruna, Spain
| | - Víctor Bautista-Hernandez
- Congenital Heart Diseases and Pediatric Cardiology Unit, Cardiac Surgery Department, Complejo Hospitalario Universitario A Coruña, A Coruna, Spain
| | - Francisco Portela Torrón
- Congenital Heart Diseases and Pediatric Cardiology Unit, Cardiac Surgery Department, Complejo Hospitalario Universitario A Coruña, A Coruna, Spain
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23
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Toneatto J, Charó NL, Galigniana NM, Piwien-Pilipuk G. Adipogenesis is under surveillance of Hsp90 and the high molecular weight Immunophilin FKBP51. Adipocyte 2015; 4:239-47. [PMID: 26451279 DOI: 10.1080/21623945.2015.1049401] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 04/30/2015] [Accepted: 05/01/2015] [Indexed: 01/21/2023] Open
Abstract
Adipose tissue plays a central role in the control of energy balance as well as in the maintenance of metabolic homeostasis. It was not until recently that the first evidences of the role of heat shock protein (Hsp) 90 and high molecular weight immunophilin FKBP51 have been described in the process of adipocyte differentiation. Recent reports describe their role in the regulation of PPARγ, a key transcription factor in the control of adipogenesis and the maintenance of the adipocyte phenotype. In addition, novel roles have been uncovered for FKBP51 in the organization of the architecture of the nucleus through its participation in the reorganization of the nuclear lamina. Therefore, the aim of this review is to integrate and discuss the recent advances in the field, with special emphasis on the roles of Hsp90 and FKBP51 in the process of adipocyte differentiation.
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24
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Gross DA, Silver DL. Cytosolic lipid droplets: from mechanisms of fat storage to disease. Crit Rev Biochem Mol Biol 2015; 49:304-26. [PMID: 25039762 DOI: 10.3109/10409238.2014.931337] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The lipid droplet (LD) is a phylogenetically conserved organelle. In eukaryotes, it is born from the endoplasmic reticulum, but unlike its parent organelle, LDs are the only known cytosolic organelles that are micellar in structure. LDs are implicated in numerous physiological and pathophysiological functions. Many aspects of the LD has captured the attention of diverse scientists alike and has recently led to an explosion in information on the LD biogenesis, expansion and fusion, identification of LD proteomes and diseases associated with LD biology. This review will provide a brief history of this fascinating organelle and provide some contemporary views of unanswered questions in LD biogenesis.
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Affiliation(s)
- David A Gross
- Program in Cardiovascular & Metabolic Disorders, Duke-NUS Graduate Medical School Singapore , Singapore , and
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25
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Agarwal N, Balasubramanyam A. Viral mechanisms of adipose dysfunction: lessons from HIV-1 Vpr. Adipocyte 2015; 4:55-9. [PMID: 26167403 DOI: 10.4161/adip.29852] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Revised: 07/07/2014] [Accepted: 07/07/2014] [Indexed: 01/02/2023] Open
Abstract
HIV-associated lipodystrophy is a heterogeneous, evolving condition associated with fundamental defects in adipose tissue differentiation, turnover and function. Although many antiretroviral drugs can affect adipose tissues adversely, clinical evidence suggests that factors associated with the virus per se could play a role. We have focused on the possibility that an HIV accessory protein, viral protein R (Vpr) could dysregulate metabolically critical transcription factors to cause the adipose dysfunction. In a recent study published in Science Translational Medicine, we utilized 2 animal models to show that Vpr, produced in tissues that sequester HIV after antiretroviral therapy, can act in a paracrine or endocrine fashion to disrupt adipocyte differentiation and function by inhibiting PPARγ target gene expression and activating glucocorticoid target gene expression. The phenotypic consequences included many features typical of the human syndrome, including accelerated lipolysis, increased macrophage infiltration in adipose tissue, diminished size of white adipose depots and hepatic steatosis. In this commentary, we summarize the background, results, and implications of these studies, and raise important questions for future investigation. More broadly, these studies suggest that chronic viral infections may be a causative factor in the pathogenesis of some forms of lipid metabolic disease, insulin resistance, and diabetes.
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26
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Abstract
Berardinelli-Seip congenital lipodystrophy (BSCL) is a very rare autosomal recessive disorder characterized by various dermatological and systemic manifestations such as lipoatrophy, hypertriglyceridemia, hepatomegaly, acanthosis nigricans, and acromegaloid features. BSCL type 2 is more common and severe, with onset in the neonatal period or in early infancy. The locus for BSCL2 has been identified on chromosome 11q13. Early recognition and differentiation from other congenital generalized lipodystrophies help in the initiation of appropriate preventive and therapeutic measures such as lifestyle modification and pharmacotherapy that helps postpone the onset of metabolic syndrome. We report BSCL type 2 in two siblings with several cutaneous manifestations like acanthosis nigricans, hypertrichosis, prominent subcutaneous veins, and increased lanugo hair.
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Affiliation(s)
- T S Mohana Rao
- Department of Dermatology, Venereology and Leprosy, King George Hospital, Visakhapatnam, Andhra Pradesh, India
| | - Kavya Chennamsetty
- Department of Dermatology, Venereology and Leprosy, King George Hospital, Visakhapatnam, Andhra Pradesh, India
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27
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Chen Y, Rui BB, Tang LY, Hu CM. Lipin Family Proteins - Key Regulators in Lipid Metabolism. ANNALS OF NUTRITION AND METABOLISM 2014; 66:10-8. [DOI: 10.1159/000368661] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 09/19/2014] [Indexed: 11/19/2022]
Abstract
Background: Proteins in the lipin family play a key role in lipid synthesis due to their phosphatidate phosphatase activity, and they also act as transcriptional coactivators to regulate the expression of genes involved in lipid metabolism. The lipin family includes three members, lipin1, lipin2, and lipin3, which exhibit tissue-specific expression, indicating that they may have distinct roles in mediating disease. To date, most studies have focused on lipin1, whereas the roles of lipin2 and lipin3 are less understood. Summary: This review introduces the structural characteristics, physiological functions, relationship to lipid metabolism, and patterns of expression of the lipin family proteins, highlighting their roles in lipid metabolic homeostasis. © 2014 S. Karger AG, Basel
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28
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Baracho MFP, Nunes AB, Hirata MH, Hirata RDC, Fajardo CM, Santos MGN, Wajchenberg BL, De Marco LA, Brandão-Neto J. Association between Pro12Ala, Pvull, Avall, Sstl and ADIPOQ single-nucleotide polymorphisms with lipid and glycemic profiles of patients with Berardinelli-Seip syndrome. ANNALS OF NUTRITION AND METABOLISM 2014; 65:272-9. [PMID: 25376908 DOI: 10.1159/000366026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 07/18/2014] [Indexed: 11/19/2022]
Abstract
BACKGROUND/AIMS Berardinelli-Seip syndrome (BSS) is a recessive autosomal genetic disorder characterized by the near loss of adipose tissue with disturbance in lipid metabolism. METHODS Biochemical and hormonal parameters and Pro12Ala, Pvull, Avall, Sstl and ADIPOQ polymorphisms in 22 patients with BSS were analyzed and examined for a possible association with lipid profiles. RESULTS Parental consanguinity, insulin resistance and diabetes mellitus were observed in 63.6, 81.8 and 59.1% of patients, respectively. All individuals presented high triglyceride levels, and 68.1% of patients showed high cholesterol levels. The Pro/Pro genotype of the Pro12Ala polymorphism of the PPARγ2 gene was found in 86.3% of patients; the Ala/Ala variant was not observed in any patient. The PvuII polymorphism of the LPL gene showed a frequency of 50% for the P1P2 variant. The AvaII polymorphism of the LDLR gene showed a similar frequency of 40.9% for both CT and TT variants. The S1S1 genotype of the Sstl polymorphism of the APOC3 gene had a frequency of 86.3%. The CC allele of the ADIPOQ polymorphism of the adiponectin gene was found in 54.6% of patients. CONCLUSIONS No association was found between lipid parameters and the relevant Pvull, Avall and Sstl polymorphisms. However, we did observe an association of the Pro12Ala and ADIPOQ polymorphisms with higher lipid levels, suggesting a close relationship between these factors.
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Affiliation(s)
- Maria F P Baracho
- Department of Internal Medicine, Federal University of Rio Grande do Norte, Natal, Brazil
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29
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Méndez-Giménez L, Rodríguez A, Balaguer I, Frühbeck G. Role of aquaglyceroporins and caveolins in energy and metabolic homeostasis. Mol Cell Endocrinol 2014; 397:78-92. [PMID: 25008241 DOI: 10.1016/j.mce.2014.06.017] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 06/25/2014] [Accepted: 06/26/2014] [Indexed: 12/23/2022]
Abstract
Aquaglyceroporins and caveolins are submicroscopic integral membrane proteins that are particularly abundant in many mammalian cells. Aquaglyceroporins (AQP3, AQP7, AQP9 and AQP10) encompass a subfamily of aquaporins that allow the movement of water, but also of small solutes, such as glycerol, across cell membranes. Glycerol constitutes an important metabolite as a substrate for de novo synthesis of triacylglycerols and glucose as well as an energy substrate to produce ATP via the mitochondrial oxidative phosphorylation. In this sense, the control of glycerol influx/efflux in metabolic organs by aquaglyceroporins plays a crucial role with the dysregulation of these glycerol channels being associated with metabolic diseases, such as obesity, insulin resistance, non-alcoholic fatty liver disease and cardiac hypertrophy. On the other hand, caveolae have emerged as relevant plasma membrane sensors implicated in a wide range of cellular functions, including endocytosis, apoptosis, cholesterol homeostasis, proliferation and signal transduction. Caveolae-coating proteins, namely caveolins and cavins, can act as scaffolding proteins within caveolae by concentrating signaling molecules involved in free fatty acid and cholesterol uptake, proliferation, insulin signaling or vasorelaxation, among others. The importance of caveolae in whole-body homeostasis is highlighted by the link between homozygous mutations in genes encoding caveolins and cavins with metabolic diseases, such as lipodystrophy, dyslipidemia, muscular dystrophy and insulin resistance in rodents and humans. The present review focuses on the role of aquaglyceroporins and caveolins on lipid and glucose metabolism, insulin secretion and signaling, energy production and cardiovascular homeostasis, outlining their potential relevance in the development and treatment of metabolic diseases.
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Affiliation(s)
- Leire Méndez-Giménez
- Metabolic Research Laboratory, Clínica Universidad de Navarra, Pamplona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Pamplona, Spain
| | - Amaia Rodríguez
- Metabolic Research Laboratory, Clínica Universidad de Navarra, Pamplona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Pamplona, Spain.
| | - Inmaculada Balaguer
- Metabolic Research Laboratory, Clínica Universidad de Navarra, Pamplona, Spain
| | - Gema Frühbeck
- Metabolic Research Laboratory, Clínica Universidad de Navarra, Pamplona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Pamplona, Spain; Department of Endocrinology and Nutrition, Clínica Universidad de Navarra, Pamplona, Spain.
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Estrogen signaling in metabolic inflammation. Mediators Inflamm 2014; 2014:615917. [PMID: 25400333 PMCID: PMC4226184 DOI: 10.1155/2014/615917] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 10/07/2014] [Indexed: 02/08/2023] Open
Abstract
There is extensive evidence supporting the interference of inflammatory activation with metabolism. Obesity, mainly visceral obesity, is associated with a low-grade inflammatory state, triggered by metabolic surplus where specialized metabolic cells such as adipocytes activate cellular stress initiating and sustaining the inflammatory program. The increasing prevalence of obesity, resulting in increased cardiometabolic risk and precipitating illness such as cardiovascular disease, type 2 diabetes, fatty liver, cirrhosis, and certain types of cancer, constitutes a good example of this association. The metabolic actions of estrogens have been studied extensively and there is also accumulating evidence that estrogens influence immune processes. However, the connection between these two fields of estrogen actions has been underacknowledged since little attention has been drawn towards the possible action of estrogens on the modulation of metabolism through their anti-inflammatory properties. In the present paper, we summarize knowledge on the modification inflammatory processes by estrogens with impact on metabolism and highlight major research questions on the field. Understanding the regulation of metabolic inflammation by estrogens may provide the basis for the development of therapeutic strategies to the management of metabolic dysfunctions.
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Farhan SMK, Robinson JF, McIntyre AD, Marrosu MG, Ticca AF, Loddo S, Carboni N, Brancati F, Hegele RA. A novel LIPE nonsense mutation found using exome sequencing in siblings with late-onset familial partial lipodystrophy. Can J Cardiol 2014; 30:1649-54. [PMID: 25475467 DOI: 10.1016/j.cjca.2014.09.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 09/11/2014] [Accepted: 09/11/2014] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Familial lipodystrophies are rare inherited disorders associated with redistribution of body fat and development of dyslipidemia, insulin resistance, and diabetes. We previously reported 2 siblings with unusual late-onset familial partial lipodystrophy in whom heretofore known causative genes had been excluded. We hypothesized they had a mutation in a novel lipodystrophy gene. METHODS Our approach centred on whole exome sequencing of the patients' DNA, together with genetic linkage analysis and a bioinformatic prioritization analysis. All candidate variants were assessed in silico and available family members were genotyped to assess segregation of mutations. RESULTS Our prioritization algorithm led us to a novel homozygous nonsense variant, namely p.Ala507fsTer563 in the hormone sensitive lipase gene encoding, an enzyme that is differentially expressed in adipocytes and steroidogenic tissues. Pathogenicity of the mutation was supported in bioinformatic analyses and variant cosegregation within the family. CONCLUSIONS We have identified a novel nonsense mutation in hormone sensitive lipase gene, which likely explains the lipodystrophy phenotype observed in these patients.
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Affiliation(s)
- Sali M K Farhan
- Departments of Medicine and Biochemistry, Western University, London, Ontario, Canada; Robarts Research, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - John F Robinson
- Robarts Research, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Adam D McIntyre
- Robarts Research, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Maria G Marrosu
- Department of Public Health, Clinical and Molecular Medicine, University of Cagliari, Cagliari, Italy
| | - Anna F Ticca
- Department of Public Health, Clinical and Molecular Medicine, University of Cagliari, Cagliari, Italy
| | - Sara Loddo
- IRCCS Casa Sollievo della Sofferenza, Istituto Mendel, San Giovanni Rotondo, Italy
| | - Nicola Carboni
- Division of Neurology, Hospital San Francesco of Nuoro, Nuoro, Italy
| | - Francesco Brancati
- Department of Medical, Oral and Biotechnological Sciences, Gabriele D'Annunzio University of Chieti-Pescara, Italy
| | - Robert A Hegele
- Departments of Medicine and Biochemistry, Western University, London, Ontario, Canada; Robarts Research, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada.
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Dyment DA, Gibson WT, Huang L, Bassyouni H, Hegele RA, Innes AM. Biallelic mutations at PPARG cause a congenital, generalized lipodystrophy similar to the Berardinelli-Seip syndrome. Eur J Med Genet 2014; 57:524-6. [PMID: 24980513 DOI: 10.1016/j.ejmg.2014.06.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 06/20/2014] [Indexed: 10/25/2022]
Abstract
We present an individual with a generalized and infantile onset lipodystrophy who later developed hypertriglyceridemia, pancreatitis, refractory diabetes, irregular menses and renal failure. She showed the hallmark features of a congenital, generalized lipodystrophy (CGL). Sequencing PPARG identified two pathogenic mutations; c.413_416delAATG; p.Glu138ValfsX168 and c.490C>T; p.R164W. The phenotype and presence of two mutations suggests that biallelic mutations at PPARG cause a CGL similar to that observed with biallelic AGPAT2 or BSCL2 mutations.
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Affiliation(s)
- D A Dyment
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Canada.
| | - W T Gibson
- Department of Medical Genetics, University of British Columbia, Vancouver, Canada
| | - L Huang
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Canada
| | - H Bassyouni
- Department of Endocrinology and Metabolism, University of Calgary, Calgary, Canada
| | - R A Hegele
- Robarts Research Institute, University of Western Ontario, London, Canada
| | - A M Innes
- Department of Medical Genetics and Alberta Children's Hospital Research Institute for Child and Maternal Health, University of Calgary, Canada
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Johansen CT, Dubé JB, Loyzer MN, MacDonald A, Carter DE, McIntyre AD, Cao H, Wang J, Robinson JF, Hegele RA. LipidSeq: a next-generation clinical resequencing panel for monogenic dyslipidemias. J Lipid Res 2014; 55:765-72. [PMID: 24503134 PMCID: PMC3966710 DOI: 10.1194/jlr.d045963] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 01/21/2014] [Indexed: 01/13/2023] Open
Abstract
We report the design of a targeted resequencing panel for monogenic dyslipidemias, LipidSeq, for the purpose of replacing Sanger sequencing in the clinical detection of dyslipidemia-causing variants. We also evaluate the performance of the LipidSeq approach versus Sanger sequencing in 84 patients with a range of phenotypes including extreme blood lipid concentrations as well as additional dyslipidemias and related metabolic disorders. The panel performs well, with high concordance (95.2%) in samples with known mutations based on Sanger sequencing and a high detection rate (57.9%) of mutations likely to be causative for disease in samples not previously sequenced. Clinical implementation of LipidSeq has the potential to aid in the molecular diagnosis of patients with monogenic dyslipidemias with a high degree of speed and accuracy and at lower cost than either Sanger sequencing or whole exome sequencing. Furthermore, LipidSeq will help to provide a more focused picture of monogenic and polygenic contributors that underlie dyslipidemia while excluding the discovery of incidental pathogenic clinically actionable variants in nonmetabolism-related genes, such as oncogenes, that would otherwise be identified by a whole exome approach, thus minimizing potential ethical issues.
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Affiliation(s)
| | | | | | - Austin MacDonald
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada N6A 5B7
| | - David E. Carter
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada N6A 5B7
| | - Adam D. McIntyre
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada N6A 5B7
| | - Henian Cao
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada N6A 5B7
| | - Jian Wang
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada N6A 5B7
| | - John F. Robinson
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada N6A 5B7
| | - Robert A. Hegele
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada N6A 5B7
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Chen W, Zhou H, Liu S, Fhaner CJ, Gross BC, Lydic TA, Reid GE. Altered lipid metabolism in residual white adipose tissues of Bscl2 deficient mice. PLoS One 2013; 8:e82526. [PMID: 24358199 PMCID: PMC3865019 DOI: 10.1371/journal.pone.0082526] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 10/24/2013] [Indexed: 11/26/2022] Open
Abstract
Mutations in BSCL2 underlie human congenital generalized lipodystrophy type 2 disease. We previously reported that Bscl2−/− mice develop lipodystrophy of white adipose tissue (WAT) due to unbridled lipolysis. The residual epididymal WAT (EWAT) displays a browning phenotype with much smaller lipid droplets (LD) and higher expression of brown adipose tissue marker proteins. Here we used targeted lipidomics and gene expression profiling to analyze lipid profiles as well as genes involved in lipid metabolism in WAT of wild-type and Bscl2−/− mice. Analysis of total saponified fatty acids revealed that the residual EWAT of Bscl2−/− mice contained a much higher proportion of oleic18:1n9 acid concomitant with a lower proportion of palmitic16:0 acid, as well as increased n3- polyunsaturated fatty acids (PUFA) remodeling. The acyl chains in major species of triacylglyceride (TG) and diacylglyceride (DG) in the residual EWAT of Bscl2−/− mice were also enriched with dietary fatty acids. These changes could be reflected by upregulation of several fatty acid elongases and desaturases. Meanwhile, Bscl2−/− adipocytes from EWAT had increased gene expression in lipid uptake and TG synthesis but not de novo lipogenesis. Both mitochondria and peroxisomal β-oxidation genes were also markedly increased in Bscl2−/− adipocytes, highlighting that these machineries were accelerated to shunt the lipolysis liberated fatty acids through uncoupling to dissipate energy. The residual subcutaneous white adipose tissue (ScWAT) was not browning but displays similar changes in lipid metabolism. Overall, our data emphasize that, other than being essential for adipocyte differentiation, Bscl2 is also important in fatty acid remodeling and energy homeostasis.
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Affiliation(s)
- Weiqin Chen
- Department of Physiology, Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
- * E-mail: .
| | - Hongyi Zhou
- Department of Physiology, Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
| | - Siyang Liu
- Department of Physiology, Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
| | - Cassie J. Fhaner
- Department of Chemistry, Michigan State University, East Lansing, Michigan, United States of America
| | - Bethany C. Gross
- Department of Chemistry, Michigan State University, East Lansing, Michigan, United States of America
| | - Todd A. Lydic
- Department of Chemistry, Michigan State University, East Lansing, Michigan, United States of America
| | - Gavin E. Reid
- Department of Chemistry, Michigan State University, East Lansing, Michigan, United States of America
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, United States of America
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Karakasilioti I, Kamileri I, Chatzinikolaou G, Kosteas T, Vergadi E, Robinson AR, Tsamardinos I, Rozgaja TA, Siakouli S, Tsatsanis C, Niedernhofer LJ, Garinis GA. DNA damage triggers a chronic autoinflammatory response, leading to fat depletion in NER progeria. Cell Metab 2013; 18:403-15. [PMID: 24011075 PMCID: PMC4116679 DOI: 10.1016/j.cmet.2013.08.011] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 05/18/2013] [Accepted: 08/09/2013] [Indexed: 12/21/2022]
Abstract
Lipodystrophies represent a group of heterogeneous disorders characterized by loss of fat tissue. However, the underlying mechanisms remain poorly understood. Using mice carrying an ERCC1-XPF DNA repair defect systematically or in adipocytes, we show that DNA damage signaling triggers a chronic autoinflammatory response leading to fat depletion. Ercc1-/- and aP2-Ercc1F/- fat depots show extensive gene expression similarities to lipodystrophic Pparγ(ldi/+) animals, focal areas of ruptured basement membrane, the reappearance of primary cilia, necrosis, fibrosis, and a marked decrease in adiposity. We find that persistent DNA damage in aP2-Ercc1F/- fat depots and in adipocytes ex vivo triggers the induction of proinflammatory factors by promoting transcriptionally active histone marks and the dissociation of nuclear receptor corepressor complexes from promoters; the response is cell autonomous and requires ataxia telangiectasia mutated (ATM). Thus, persistent DNA damage-driven autoinflammation plays a causative role in adipose tissue degeneration, with important ramifications for progressive lipodystrophies and natural aging.
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Affiliation(s)
- Ismene Karakasilioti
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, 70013 Heraklion, Crete, Greece; Department of Biology, University of Crete, 71409 Heraklion, Crete, Greece
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Knebel B, Kotzka J, Lehr S, Hartwig S, Avci H, Jacob S, Nitzgen U, Schiller M, März W, Hoffmann MM, Seemanova E, Haas J, Muller-Wieland D. A mutation in the c-fos gene associated with congenital generalized lipodystrophy. Orphanet J Rare Dis 2013; 8:119. [PMID: 23919306 PMCID: PMC3750569 DOI: 10.1186/1750-1172-8-119] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 08/01/2013] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Congenital generalized lipodystrophy (CGL) or Berardinelli-Seip congenital lipodystrophy (BSCL) is a rare genetic syndrome characterized by the absence of adipose tissue. As CGL is thought to be related to malfunctions in adipocyte development, genes involved in the mechanisms of adipocyte biology and maintenance or differentiation of adipocytes, especially transcription factors are candidates. Several genes (BSCL1-4) were found to be associated to the syndrome but not all CGL patients carry mutations in these genes. METHODS AND RESULTS In a patient with CGL and insulin resistance we investigated the known candidate genes but the patient did not carry a relevant mutation. Analyses of the insulin activated signal transduction pathways in isolated fibroblasts of the patient revealed a postreceptor defect altering expression of the immediate early gene c-fos. Sequence analyses revealed a novel homozygous point mutation (c.-439, T→A) in the patients' c-fos promoter. The point mutation was located upstream of the well characterized promoter elements in a region with no homology to any known cis-elements. The identified mutation was not detected in a total of n=319 non lipodystrophic probands. In vitro analyses revealed that the mutation facilitates the formation of a novel and specific protein/DNA complex. Using mass spectrometry we identified the proteins of this novel complex. Cellular investigations demonstrate that the wild type c-fos promoter can reconstitute the signaling defect in the patient, excluding further upstream signaling alterations, and vice versa the investigations with the c-fos promoter containing the identified mutation generally reduce basal and inducible c-fos transcription activity. As a consequence of the identified point mutation gene expression including c-Fos targeted genes is significantly altered, shown exemplified in cells of the patient. CONCLUSION The immediate-early gene c-fos is one essential transcription factor to initiate adipocyte differentiation. According to the role of c-fos in adipocyte differentiation our findings of a mutation that initiates a repression mechanism at c-fos promoter features the hypothesis that diminished c-fos expression might play a role in CGL by interfering with adipocyte development.
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Affiliation(s)
- Birgit Knebel
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center at the Heinrich-Heine-University Duesseldorf, Leibniz Center for Diabetes Research, Duesseldorf, Germany
| | - Jorg Kotzka
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center at the Heinrich-Heine-University Duesseldorf, Leibniz Center for Diabetes Research, Duesseldorf, Germany
| | - Stefan Lehr
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center at the Heinrich-Heine-University Duesseldorf, Leibniz Center for Diabetes Research, Duesseldorf, Germany
| | - Sonja Hartwig
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center at the Heinrich-Heine-University Duesseldorf, Leibniz Center for Diabetes Research, Duesseldorf, Germany
| | - Haluk Avci
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center at the Heinrich-Heine-University Duesseldorf, Leibniz Center for Diabetes Research, Duesseldorf, Germany
| | - Sylvia Jacob
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center at the Heinrich-Heine-University Duesseldorf, Leibniz Center for Diabetes Research, Duesseldorf, Germany
| | - Ulrike Nitzgen
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center at the Heinrich-Heine-University Duesseldorf, Leibniz Center for Diabetes Research, Duesseldorf, Germany
| | - Martina Schiller
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center at the Heinrich-Heine-University Duesseldorf, Leibniz Center for Diabetes Research, Duesseldorf, Germany
| | - Winfried März
- 2nd Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
- Synlab Centre of Laboratory Diagnostics Heidelberg, Heidelberg, Germany
| | - Michael M Hoffmann
- Division of Clinical Chemistry, University Medical Center, Freiburg, Germany
- Department of Medicine, University Medical Center, Freiburg, Germany
| | - Eva Seemanova
- Department of Clinical Genetics, Institute of Biology, and Medical Genetics, 2nd Medical School, Charles University, Prague, Czech Republic
| | - Jutta Haas
- Institute for Diabetes Research, Department of General Internal Medicine, Asklepios Clinic St. Georg, Asklepios Campus Hamburg, Medical Faculty of Semmelweis University, Hamburg, Germany
| | - Dirk Muller-Wieland
- Institute for Diabetes Research, Department of General Internal Medicine, Asklepios Clinic St. Georg, Asklepios Campus Hamburg, Medical Faculty of Semmelweis University, Hamburg, Germany
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Prieur X, Dollet L, Takahashi M, Nemani M, Pillot B, Le May C, Mounier C, Takigawa-Imamura H, Zelenika D, Matsuda F, Fève B, Capeau J, Lathrop M, Costet P, Cariou B, Magré J. Thiazolidinediones partially reverse the metabolic disturbances observed in Bscl2/seipin-deficient mice. Diabetologia 2013; 56:1813-25. [PMID: 23680914 DOI: 10.1007/s00125-013-2926-9] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 04/11/2013] [Indexed: 11/26/2022]
Abstract
AIMS/HYPOTHESIS Mutations in BSCL2/seipin cause Berardinelli-Seip congenital lipodystrophy (BSCL), a rare recessive disorder characterised by near absence of adipose tissue and severe insulin resistance. We aimed to determine how seipin deficiency alters glucose and lipid homeostasis and whether thiazolidinediones can rescue the phenotype. METHODS Bscl2 (-/-) mice were generated and phenotyped. Mouse embryonic fibroblasts (MEFs) were used as a model of adipocyte differentiation. RESULTS As observed in humans, Bscl2 (-/-) mice displayed an early depletion of adipose tissue, with insulin resistance and severe hepatic steatosis. However, Bscl2 (-/-) mice exhibited an unexpected hypotriglyceridaemia due to increased clearance of triacylglycerol-rich lipoproteins (TRL) and uptake of fatty acids by the liver, with reduced basal energy expenditure. In vitro experiments with MEFs demonstrated that seipin deficiency led to impaired late adipocyte differentiation and increased basal lipolysis. Thiazolidinediones were able to rescue the adipogenesis impairment but not the alteration in lipolysis in Bscl2 (-/-) MEFs. In vivo treatment of Bscl2 (-/-) mice with pioglitazone for 9 weeks increased residual inguinal and mesenteric fat pads as well as plasma leptin and adiponectin concentrations. Pioglitazone treatment increased energy expenditure and improved insulin resistance, hypotriglyceridaemia and liver steatosis in these mice. CONCLUSIONS/INTERPRETATION Seipin plays a key role in the differentiation and storage capacity of adipocytes, and affects glucose and lipid homeostasis. The hypotriglyceridaemia observed in Bscl2 (-/-) mice is linked to increased uptake of TRL by the liver, offering a new model of liver steatosis. The demonstration that the metabolic complications associated with BSCL can be partially rescued with pioglitazone treatment opens an interesting therapeutic perspective for BSCL patients.
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Affiliation(s)
- X Prieur
- Inserm UMR_S1087, L'Institut du Thorax, IRS-UN, Nantes Cedex 1, France.
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Bowers J, Terrien J, Clerget-Froidevaux MS, Gothié JD, Rozing MP, Westendorp RGJ, van Heemst D, Demeneix BA. Thyroid hormone signaling and homeostasis during aging. Endocr Rev 2013; 34:556-89. [PMID: 23696256 DOI: 10.1210/er.2012-1056] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Studies in humans and in animal models show negative correlations between thyroid hormone (TH) levels and longevity. TH signaling is implicated in maintaining and integrating metabolic homeostasis at multiple levels, notably centrally in the hypothalamus but also in peripheral tissues. The question is thus raised of how TH signaling is modulated during aging in different tissues. Classically, TH actions on mitochondria and heat production are obvious candidates to link negative effects of TH to aging. Mitochondrial effects of excess TH include reactive oxygen species and DNA damage, 2 factors often considered as aging accelerators. Inversely, caloric restriction, which can retard aging from nematodes to primates, causes a rapid reduction of circulating TH, reducing metabolism in birds and mammals. However, many other factors could link TH to aging, and it is these potentially subtler and less explored areas that are highlighted here. For example, effects of TH on membrane composition, inflammatory responses, stem cell renewal and synchronization of physiological responses to light could each contribute to TH regulation of maintenance of homeostasis during aging. We propose the hypothesis that constraints on TH signaling at certain life stages, notably during maturity, are advantageous for optimal aging.
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Affiliation(s)
- J Bowers
- Muséum national d'Histoire Naturelle, Laboratoire de Physiologie Générale et Comparée, Unité Mixte de Recherche, Centre National de la Recherche Scientifique 7221, 75231 Paris cedex 5, France
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Dollet L, Magré J, Cariou B, Prieur X. Function of seipin: new insights from Bscl2/seipin knockout mouse models. Biochimie 2013; 96:166-72. [PMID: 23831461 DOI: 10.1016/j.biochi.2013.06.022] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 06/20/2013] [Indexed: 11/30/2022]
Abstract
Mutations in BSCL2/seipin cause Berardinelli-Seip congenital lipodystrophy (BSCL), a rare recessive disorder characterized by near absence of adipose tissue and severe insulin resistance. Since the discovery of the gene in 2001, several cellular studies intended to unravel the biological function of seipin and revealed that seipin-deficiency alters adipocyte differentiation and lipid droplet morphology. However, the exact function of the protein remains unclear and the pathophysiology of BSCL in patients carrying BSCL2/seipin mutations is poorly understood. A major breakthrough in the field of seipin came recently, with the demonstration by three independent groups that Bscl2-deficient mice (Bscl2(-/-)) developed severe lipodystrophy with only residual white and brown fat pads, validating a critical role for seipin in adipose tissue homeostasis. Using in vivo, ex vivo and in vitro methods, these studies demonstrate that seipin plays a key role in adipogenesis, lipid droplet homeostasis and cellular triglyceride lipolysis. In addition to adipose tissue impairment, Bscl2(-/-) mice are diabetic and display severe hepatic steatosis. Treatment with thiazolidinediones (TZD) in Bscl2(-/-) mice increases adipose tissue mass and partially rescues the metabolic complications associated with BSCL, highlighting that lipoatrophy is the major cause of the BSCL phenotype. Except an unexpected hypotriglyceridemia, Bscl2(-/-) mice phenotype represents an almost perfect picture of the human disease. This review analyses how these studies using Bscl2(-/-) mice brought new insights into seipin function and the mechanisms involved in the pathophysiology of BSCL. We also analyse some of the human data in the light of the mouse phenotyping and discuss the validity of Bscl2(-/-) mice model to test pharmaceutical approaches for treating BSCL and its associated metabolic complications.
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Affiliation(s)
- Lucile Dollet
- INSERM UMR 1087, IRS-UN, 8 quai Moncousu, BP 70721, 44007 Nantes Cedex 1, France
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Lee YH, Mottillo EP, Granneman JG. Adipose tissue plasticity from WAT to BAT and in between. Biochim Biophys Acta Mol Basis Dis 2013; 1842:358-69. [PMID: 23688783 DOI: 10.1016/j.bbadis.2013.05.011] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 04/21/2013] [Accepted: 05/06/2013] [Indexed: 01/09/2023]
Abstract
Adipose tissue plays an essential role in regulating energy balance through its metabolic, cellular and endocrine functions. Adipose tissue has been historically classified into anabolic white adipose tissue and catabolic brown adipose tissue. An explosion of new data, however, points to the remarkable heterogeneity among the cells types that can become adipocytes, as well as the inherent metabolic plasticity of mature cells. These data indicate that targeting cellular and metabolic plasticity of adipose tissue might provide new avenues for treatment of obesity-related diseases. This review will discuss the developmental origins of adipose tissue, the cellular complexity of adipose tissues, and the identification of progenitors that contribute to adipogenesis throughout development. We will touch upon the pathological remodeling of adipose tissue and discuss how our understanding of adipose tissue remodeling can uncover new therapeutic targets. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease.
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Affiliation(s)
- Yun-Hee Lee
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Emilio P Mottillo
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - James G Granneman
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI 48201, USA.
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Qiu W, Wee K, Takeda K, Lim X, Sugii S, Radda GK, Han W. Suppression of adipogenesis by pathogenic seipin mutant is associated with inflammatory response. PLoS One 2013; 8:e57874. [PMID: 23520483 PMCID: PMC3592919 DOI: 10.1371/journal.pone.0057874] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 01/29/2013] [Indexed: 02/07/2023] Open
Abstract
Background While pathogenic mutations in BSCL2/Seipin cause congenital generalized lipodystrophy, the underlying mechanism is largely unknown. In this study, we investigated whether and how the pathogenic missense A212P mutation of Seipin (Seipin-A212P) inhibits adipogenesis. Methodology/Results We analyzed gene expression and lipid accumulation in stable 3T3-L1 cell lines expressing wild type (3T3-WT), non-lipodystrophic mutants N88S (3T3-N88S) and S90L (3T3-S90L), or lipodystrophic mutant A212P Seipin (3T3-A212P). When treated with adipogenic cocktail, 3T3-WT, 3T3-N88S and 3T3-S90L cells exhibited proper differentiation into mature adipocytes, indistinguishable from control 3T3-L1 cells. In contrast, adipogenesis was significantly impaired in 3T3-A212P cells. The defective adipogenesis in 3T3-A212P cells could be partially rescued by either PPARγ agonist or PPARγ overexpression. Gene expression profiling by microarray revealed that inhibition of adipogenesis was associated with activation of inflammatory genes including IL-6 and iNOS. We further demonstrated that Seipin-A212P expression at pre-differentiation stages significantly activated inflammatory responses by using an inducible expression system. The inflammation-associated inhibition of adipogenesis could be rescued by treatment with anti-inflammatory agents. Conclusions These results suggest that pathogenic Seipin-A212P inhibits adipogenesis and the inhibition is associated with activation of inflammatory pathways at pre-differentiation stages. Use of anti-inflammatory drugs may be a potential strategy for the treatment of lipodystrophy.
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Affiliation(s)
- Wenjie Qiu
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Agency for Science, Technology and Research, Singapore, Republic of Singapore
| | - Kenneth Wee
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Agency for Science, Technology and Research, Singapore, Republic of Singapore
| | - Kosuke Takeda
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Agency for Science, Technology and Research, Singapore, Republic of Singapore
| | - Xuemei Lim
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Agency for Science, Technology and Research, Singapore, Republic of Singapore
| | - Shigeki Sugii
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Agency for Science, Technology and Research, Singapore, Republic of Singapore
- Cardiovascular and Metabolic Disorders Program, Duke-National University of Singapore Graduate Medical School, Singapore, Republic of Singapore
- * E-mail: (WH) (SS); (SS) (WH)
| | - George K. Radda
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Agency for Science, Technology and Research, Singapore, Republic of Singapore
| | - Weiping Han
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Agency for Science, Technology and Research, Singapore, Republic of Singapore
- Cardiovascular and Metabolic Disorders Program, Duke-National University of Singapore Graduate Medical School, Singapore, Republic of Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Republic of Singapore
- Metabolism in Human Diseases, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Republic of Singapore
- * E-mail: (WH) (SS); (SS) (WH)
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43
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Peng XG, Ju S, Fang F, Wang Y, Fang K, Cui X, Liu G, Li P, Mao H, Teng GJ. Comparison of brown and white adipose tissue fat fractions in ob, seipin, and Fsp27 gene knockout mice by chemical shift-selective imaging and (1)H-MR spectroscopy. Am J Physiol Endocrinol Metab 2013; 304:E160-7. [PMID: 23149622 DOI: 10.1152/ajpendo.00401.2012] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Brown adipose tissue (BAT) plays a key role in thermogenesis to protect the body from cold and obesity. White adipose tissue (WAT) stores excess energy in the form of triglycerides. To better understand the genetic effect on regulation of WAT and BAT, we investigated the fat fraction (FF) in two types of adipose tissues in ob/ob, human BSCL2/seipin gene knockout (SKO), Fsp27 gene knockout (Fsp27(-/-)), and wild-type (WT) mice in vivo using chemical shift selective imaging and (1)H-MR spectroscopy. We reported that the visceral fat volume in WAT was significantly larger in ob/ob mice, but visceral fat volumes were lower in SKO and Fsp27(-/-) mice compared with WT mice. BAT FF was significantly higher in ob/ob mice than the WT group and similar to that of WAT. In contrast, WAT FFs in SKO and Fsp27(-/-) mice were lower and similar to that of BAT. The adipocyte size of WAT in ob/ob mice and the BAT adipocyte size in ob/ob, SKO, and Fsp27 mice were significantly larger compared with WT mice. However, the WAT adipocyte size was significantly smaller in SKO mice than in WT mice. Positive correlations were observed between the adipocyte size and FFs of WAT and BAT. These results suggested that smaller adipocyte size correlates with lower FFs of WAT and BAT. In addition, the differences in FFs in WAT and BAT measured by MR methods in different mouse models were related to the different regulation effects of ob, seipin, or Fsp27 gene on developing WAT and BAT.
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Affiliation(s)
- Xin-Gui Peng
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, China
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Prasad NR, Reddy PA, Menon B, Karthik TS, Ahmed F, Chakravarthy M. Recurrent stroke as a presenting feature of acquired partial lipodystrophy. Indian J Endocrinol Metab 2012; 16:S455-S457. [PMID: 23565465 PMCID: PMC3603113 DOI: 10.4103/2230-8210.104130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Acquired partial lipodystrophy (PL) (Barraquer-Simons syndrome) is a rare condition with onset in childhood, and it is characterized by progressive loss of subcutaneous fat in a cephalocaudal fashion. This report describes a case of acquired PL in a 16-year-old girl, who had progressive loss of facial fat since 3 years. Systemic lupus erythematosus (SLE), anticardiolipin antibody, primary hypothyroidism, diabetes, and dyslipidemia may antedate the development of complications such as cerebrovascular stroke and cardiovascular disease. The girl had developed recurrent left hemiparesis, and withdrawn from school due to poor performance.
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Affiliation(s)
- Namburi R. Prasad
- Department of Endocrinology, Narayana Medical College, & Hospital, ChinthareddyPalem, Nellore, District, Andhra Pradesh, India
| | - Ponnala A. Reddy
- Department of Endocrinology, Narayana Medical College, & Hospital, ChinthareddyPalem, Nellore, District, Andhra Pradesh, India
| | - Bindu Menon
- Department of Neurology, Narayana Medical College, & Hospital, ChinthareddyPalem, Nellore, District, Andhra Pradesh, India
| | - T. S. Karthik
- Department of Endocrinology, Narayana Medical College, & Hospital, ChinthareddyPalem, Nellore, District, Andhra Pradesh, India
| | - Faizal Ahmed
- Department of Endocrinology, Narayana Medical College, & Hospital, ChinthareddyPalem, Nellore, District, Andhra Pradesh, India
| | - Mithun Chakravarthy
- Department of Endocrinology, Narayana Medical College, & Hospital, ChinthareddyPalem, Nellore, District, Andhra Pradesh, India
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45
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Tang SQ, Jiang QY, Yang CF, Zou XT, Dong XY. [Research and development of Lipin family.]. YI CHUAN = HEREDITAS 2012; 32:981-93. [PMID: 20943485 DOI: 10.3724/sp.j.1005.2010.00981] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Lipin family including at least three members Lipin 1, Lipin 2, and Lipin 3 is a critical regulatory enzyme identified recently, which plays dual roles in lipid metabolisms. Lipin family has physiological effects not only on regulating lipid metabolism, but also on maintaining normal peripheral nervous functions, liver lipoprotein secretion, cell morphous, reproductive functions, and energy homeostasis. Since mutations in Lipin gene express may be associated with AIDS, insulin resistance, obesity, diabetes mellitus, and the other diseases of metabolic syndrome, Lipin may be a new useful target in treatment of above-mentioned clinical-related diseases. In this article, we focused on discovery, construction features, expression, regulatory mechanism, and biological functions of Lipin, as well as its correlation research with clinical-related diseases.
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46
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Quantitative Whole-Body MRI in Familial Partial Lipodystrophy Type 2: Changes in Adipose Tissue Distribution Coincide With Biochemical Improvement. AJR Am J Roentgenol 2012; 199:W602-6. [DOI: 10.2214/ajr.11.8110] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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47
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Ramanathan N, Ahmed M, Raffan E, Stewart CL, O'Rahilly S, Semple RK, Raef H, Rochford JJ. Identification and Characterisation of a Novel Pathogenic Mutation in the Human Lipodystrophy Gene AGPAT2 : C48R: A Novel Mutation in AGPAT2. JIMD Rep 2012; 9:73-80. [PMID: 23430550 PMCID: PMC3565662 DOI: 10.1007/8904_2012_181] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 09/10/2012] [Accepted: 09/11/2012] [Indexed: 12/12/2022] Open
Abstract
Loss-of-function mutations in AGPAT2, encoding 1-acylglycerol-3-phosphate-O-acyltransferase 2 (AGPAT2), produce congenital generalised lipodystrophy (CGL). We screened the AGPAT2 gene in two siblings who presented with pseudoacromegaly, diabetes and severe dyslipidaemia and identified a novel mutation in AGPAT2 causing a single amino acid substitution, p.Cys48Arg. We subsequently investigated the molecular pathogenic mechanism linking both this mutation and the previously reported p.Leu228Pro mutation to clinical disease. Wild-type and mutant AGPAT2 were expressed in control and AGPAT2-deficient preadipocyte cell lines. mRNA and protein expression was determined, and the ability of each AGPAT2 species to rescue adipocyte differentiation in AGPAT2-deficient cells was assessed. Protein levels of both p.Cys48Arg and p.Leu228Pro AGPAT2 were significantly reduced compared with that of wild-type AGPAT2 despite equivalent mRNA levels. Stable expression of wild-type AGPAT2 partially rescued adipogenesis in AGPAT2 deficient preadipocytes, whereas stable expression of p.Cys48Arg or p.Leu228Pro AGPAT2 did not. In conclusion, unusually severe dyslipidaemia and pseudoacromegaloid overgrowth in patients with diabetes should alert physicians to the possibility of lipodystrophy. Both the previously unreported pathogenic p.Cys48Arg mutation in AGPAT2, and the known p.Leu228Pro mutation result in decreased AGPAT2 protein expression in developing adipocytes. It is most likely that the CGL seen in homozygous carriers of these mutations is largely accounted for by loss of protein expression.
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Affiliation(s)
- N Ramanathan
- Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge Metabolic Research Laboratories, Hills Road, Cambridge, CB2 0QQ, UK
- Institute of Medical Biology, Immunos, 8A Biomedical Grove, 138648, Singapore, Republic of Singapore
| | - M Ahmed
- Department of Medicine, King Faisal Specialist Hospital and Research Centre, 3354, Riyadh, 11211, Saudi Arabia
| | - E Raffan
- Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge Metabolic Research Laboratories, Hills Road, Cambridge, CB2 0QQ, UK
| | - C L Stewart
- Institute of Medical Biology, Immunos, 8A Biomedical Grove, 138648, Singapore, Republic of Singapore
| | - S O'Rahilly
- Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge Metabolic Research Laboratories, Hills Road, Cambridge, CB2 0QQ, UK
| | - R K Semple
- Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge Metabolic Research Laboratories, Hills Road, Cambridge, CB2 0QQ, UK
| | - H Raef
- Department of Medicine, King Faisal Specialist Hospital and Research Centre, 3354, Riyadh, 11211, Saudi Arabia
| | - J J Rochford
- Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge Metabolic Research Laboratories, Hills Road, Cambridge, CB2 0QQ, UK.
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48
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Valerio CM, Zajdenverg L, de Oliveira JEP, Mory PB, Moyses RS, Godoy-Matos AF. Body composition study by dual-energy x-ray absorptiometry in familial partial lipodystrophy: finding new tools for an objective evaluation. Diabetol Metab Syndr 2012; 4:40. [PMID: 22938045 PMCID: PMC3524775 DOI: 10.1186/1758-5996-4-40] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 08/23/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Familial partial lipodystrophies (FPLD) are clinically heterogeneous disorders characterized by selective loss of adipose tissue, insulin resistance and metabolic complications. Until genetic studies become available for clinical practice, clinical suspicion and pattern of fat loss are the only parameters leading clinicians to consider the diagnosis. The objective of this study was to compare body composition by dual energy X-ray absorptiometry (DXA) in patients with FPLD and control subjects, aiming to find objective variables for evaluation of FPLD. METHODS Eighteen female patients with partial lipodystrophy phenotype and 16 healthy controls, matched for body mass index, sex and age were studied. All participants had body fat distribution evaluated by DXA measures. Fasting blood samples were obtained for evaluation of plasma leptin, lipid profile and inflammatory markers. Genetic studies were carried out on the 18 patients selected that were included for statistical analysis. Thirteen women confirmed diagnosis of Dunnigan-type FPLD (FPLD2). RESULTS DXA revealed a marked decrease in truncal fat and 3 folds decrease in limbs fat percentage in FPLD2 patients (p <0.001). Comparative analysis showed that ratio between trunk and lower limbs fat mass, characterized as Fat Mass Ratio (FMR), had a greater value in FLPD2 group (1.86 ± 0.43 vs controls 0.93 ± 0.10; p <0.001) and a improved accuracy for evaluating FPLD2 with a cut-off point of 1.2. Furthermore, affected women showed hypoleptinemia (FLPD2 4.9 ± 2.0 vs controls 18.2 ± 6.8; p <0.001), insulin resistance and a more aggressive lipid profile. CONCLUSION In this study, assessment of body fat distribution by DXA permitted an objective characterization of FLPD2. A consistent pattern with marked fat reduction of lower body was observed in affected patients. To our knowledge this is the first time that cut-off values of objective variables were proposed for evaluation of FPLD2.
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Affiliation(s)
- Cynthia M Valerio
- Metabolism Unit, Instituto Estadual de Diabetes e Endocrinologia, Rio de Janeiro and Catholic University, Rio de Janeiro, Brazil
- Instituto Estadual de Diabetes e Endocrinologia, Rua Moncorvo Filho 90 – Centro, Rio de Janeiro, RJ CEP 20211-340, Brasil
| | - Lenita Zajdenverg
- Department of Nutrology, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | | | - Patricia B Mory
- Division of Endocrinology, Universidade Federal de Sao Paulo, São Paulo, SP, Brazil
| | - Regina S Moyses
- Division of Endocrinology, Universidade Federal de Sao Paulo, São Paulo, SP, Brazil
| | - Amélio F Godoy-Matos
- Metabolism Unit, Instituto Estadual de Diabetes e Endocrinologia, Rio de Janeiro and Catholic University, Rio de Janeiro, Brazil
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Campeau PM, Astapova O, Martins R, Bergeron J, Couture P, Hegele RA, Leff T, Gagné C. Clinical and molecular characterization of a severe form of partial lipodystrophy expanding the phenotype of PPARγ deficiency. J Lipid Res 2012; 53:1968-78. [PMID: 22750678 DOI: 10.1194/jlr.p025437] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Familial partial lipodystrophy (FPLD) is characterized by abnormal fat distribution and a metabolic syndrome with hypertriglyceridemia. We identified a family with a severe form of FPLD3 with never-reported clinical features and a novel mutation affecting the DNA binding domain of PPARγ (E157D). Apart from the lipodystrophy and severe metabolic syndrome, individuals presented musculoskeletal and hematological issues. E157D heterozygotes had a muscular habitus yet displayed muscle weakness and myopathy. Also, E157D heterozygotes presented multiple cytopenias and a susceptibility to autoimmune disease. In vitro studies showed that the E157D mutation does not decrease the receptor's affinity to classical PPAR response elements or its responsiveness to a PPARγ agonist, yet it severely reduces its target gene transcription. Microarray experiments demonstrated a decreased activation of a wide array of genes, including genes involved in the PPAR response, the immune response, hematopoiesis, and metabolism in muscle. In addition, a subset of genes with cryptic PPAR response elements was activated. In summary, we describe a large family with a novel PPARγ mutation, which extends the clinical phenotype of FPLD3 to include muscular, immune, and hematological features. Together, our results support the role of PPARγ in controlling homeostasis of multiple systems beyond lipid metabolism.
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Affiliation(s)
- Philippe M Campeau
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
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Abstract
Excess body adiposity, especially abdominal obesity and ectopic fat accumulation, are key risk factors in the development of a number of chronic diseases. The advent of in vivo imaging methodologies that allow direct assessment of total body fat and its distribution have been pivotal in this process. They have helped to identify a number of sub-phenotypes in the general population whose metabolic risk factors are not commensurate with their BMI. At least two such sub-phenotypes have been identified: subjects with normal BMI, but excess intra-abdominal (visceral) fat (with or without increased ectopic fat) and subjects with elevated BMI (> 25 kg/m(2)) but low visceral and ectopic fat. The former sub-phenotype is associated with adverse metabolic profiles, while the latter is associated with a metabolically normal phenotype, despite a high BMI. Here, examples of these phenotypes are presented and the value of carrying out enhanced phenotypical characterisation of subjects in interventional studies discussed.
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