Lamins and metabolism

2016 ◽  
Vol 131 (2) ◽  
pp. 105-111 ◽  
Author(s):  
Chayki Charar ◽  
Yosef Gruenbaum

Lamins are nuclear intermediate filaments (IFs) with important roles in most nuclear activities, including nuclear organization and cell-cycle progression. Mutations in human lamins cause over 17 different diseases, termed laminopathies. Most of these diseases are autosomal dominant and can be roughly divided into four major groups: muscle diseases, peripheral neuronal diseases, accelerated aging disorders and metabolic diseases including Dunnigan type familial partial lipodystrophy (FLPD), acquired partial lipodystrophy (APL) and autosomal dominant leucodystrophy. Mutations in lamins are also associated with the metabolic syndrome (MS). Cells derived from patients suffering from metabolic laminopathies, as well as cells derived from the corresponding animal models, show a disruption of the mechanistic target of rapamycin (mTOR) pathway, abnormal autophagy, altered proliferative rate and down-regulation of genes that regulate adipogenesis. In addition, treating Hutchinson–Gilford progeria syndrome (HGPS) cells with the mTOR inhibitor rapamycin improves their fate. In this review, we will discuss the ways by which lamin genes are involved in the regulation of cell metabolism.

2021 ◽  
Vol 22 (14) ◽  
pp. 7327
Author(s):  
Juan A. Fafián-Labora ◽  
Miriam Morente-López ◽  
Fco. Javier de Toro ◽  
María C. Arufe

Hutchinson–Gilford progeria syndrome (HGPS) is a deadly childhood disorder, which is considered a very rare disease. It is caused by an autosomal dominant mutation on the LMNA gene, and it is characterized by accelerated aging. Human cell lines from HGPS patients and healthy parental controls were studied in parallel using next-generation sequencing (NGS) to unravel new non-previously altered molecular pathways. Nine hundred and eleven transcripts were differentially expressed when comparing healthy versus HGPS cell lines from a total of 21,872 transcripts; ITPR1, ITPR3, CACNA2D1, and CAMK2N1 stood out among them due to their links with calcium signaling, and these were validated by Western blot analysis. It was observed that the basal concentration of intracellular Ca2+ was statistically higher in HGPS cell lines compared to healthy ones. The relationship between genes involved in Ca2+ signaling and mitochondria-associated membranes (MAM) was demonstrated through cytosolic calcium handling by means of an automated fluorescent plate reading system (FlexStation 3, Molecular Devices), and apoptosis and mitochondrial ROS production were examined by means of flow cytometry analysis. Altogether, our data suggest that the Ca2+ signaling pathway is altered in HGPS at least in part due to the overproduction of reactive oxygen species (ROS). Our results unravel a new therapeutic window for the treatment of this rare disease and open new strategies to study pathologies involving both accelerated and healthy aging.


2009 ◽  
Vol 9 ◽  
pp. 1449-1462 ◽  
Author(s):  
Baomin Li ◽  
Sonali Jog ◽  
Jose Candelario ◽  
Sita Reddy ◽  
Lucio Comai

Syndromes of accelerated aging could provide an entry point for identifying and dissecting the cellular pathways that are involved in the development of age-related pathologies in the general population. However, their usefulness for aging research has been controversial, as it has been argued that these diseases do not faithfully reflect the process of natural aging. Here we review recent findings on the molecular basis of two progeroid diseases, Werner syndrome (WS) and Hutchinson-Gilford progeria syndrome (HGPS), and highlight functional connections to cellular processes that may contribute to normal aging.


2021 ◽  
Vol 13 (575) ◽  
pp. eabd2655
Author(s):  
Wei Wang ◽  
Yuxuan Zheng ◽  
Shuhui Sun ◽  
Wei Li ◽  
Moshi Song ◽  
...  

Understanding the genetic and epigenetic bases of cellular senescence is instrumental in developing interventions to slow aging. We performed genome-wide CRISPR-Cas9–based screens using two types of human mesenchymal precursor cells (hMPCs) exhibiting accelerated senescence. The hMPCs were derived from human embryonic stem cells carrying the pathogenic mutations that cause the accelerated aging diseases Werner syndrome and Hutchinson-Gilford progeria syndrome. Genes whose deficiency alleviated cellular senescence were identified, including KAT7, a histone acetyltransferase, which ranked as a top hit in both progeroid hMPC models. Inactivation of KAT7 decreased histone H3 lysine 14 acetylation, repressed p15INK4b transcription, and alleviated hMPC senescence. Moreover, lentiviral vectors encoding Cas9/sg-Kat7, given intravenously, alleviated hepatocyte senescence and liver aging and extended life span in physiologically aged mice as well as progeroid Zmpste24−/− mice that exhibit a premature aging phenotype. CRISPR-Cas9–based genetic screening is a robust method for systematically uncovering senescence genes such as KAT7, which may represent a therapeutic target for developing aging interventions.


2019 ◽  
Vol 30 (6) ◽  
pp. 573-580 ◽  
Author(s):  
Nickolay K. Isaev ◽  
Elena V. Stelmashook ◽  
Elisaveta E. Genrikhs

AbstractHuman aging affects the entire organism, but aging of the brain must undoubtedly be different from that of all other organs, as neurons are highly differentiated postmitotic cells, for the majority of which the lifespan in the postnatal period is equal to the lifespan of the entire organism. In this work, we examine the distinctive features of brain aging and neurogenesis during normal aging, pathological aging (Alzheimer’s disease), and accelerated aging (Hutchinson-Gilford progeria syndrome and Werner syndrome).


2010 ◽  
Vol 38 (1) ◽  
pp. 281-286 ◽  
Author(s):  
Dawn T. Smallwood ◽  
Sue Shackleton

HGPS (Hutchinson–Gilford progeria syndrome) is a severe childhood disorder that appears to mimic an accelerated aging process. The disease is most commonly caused by gene mutations that disrupt the normal post-translational processing of lamin A, a structural component of the nuclear envelope. Impaired processing results in aberrant retention of a farnesyl group at the C-terminus of lamin A, leading to altered membrane dynamics. It has been widely proposed that persistence of the farnesyl moiety is the major factor responsible for the disease, prompting clinical trials of farnesyltransferase inhibitors to prevent lamin A farnesylation in children afflicted with HGPS. Although there is evidence implicating farnesylation in causing some of the cellular defects of HGPS, results of several recent studies suggest that aberrant lamin A farnesylation is not the only determinant of the disease. These findings have important implications for the design of treatments for this devastating disease.


2005 ◽  
Vol 289 (3) ◽  
pp. R663-R669 ◽  
Author(s):  
Robert A. Hegele ◽  
Rebecca L. Pollex

The metabolic syndrome (MetS) is a common phenotype that is clinically defined by threshold values applied to measures of central obesity, dysglycemia, dyslipidemia, and/or elevated blood pressure, which must be present concurrently in any one of a variety of combinations. Insulin resistance, although not a defining component of the MetS, is nonetheless considered to be a core feature. MetS is important because it is rapidly growing in prevalence and is strongly related to the development of cardiovascular disease. To define etiology, pathogenesis and expression of MetS, we have studied patients, specifically Canadian families and communities. One example is familial partial lipodystrophy (FPLD), a rare monogenic form of insulin resistance caused by mutations in either LMNA, encoding nuclear lamin A/C (subtype FPLD2), or in PPARG, encoding peroxisomal proliferator-activated receptor-γ (subtype FPLD3). Because it evolves slowly and recapitulates key clinical and biochemical attributes, FPLD seems to be a useful monogenic model of MetS. A second example is the disparate MetS prevalence between two Canadian aboriginal groups that is mirrored by disparate prevalence of diabetes and cardiovascular disease. Careful phenotypic evaluation of such special cases of human MetS by using a wide range of diagnostic methods, an approach called “phenomics,” may help uncover early presymptomatic disease biomarkers, which in turn might reveal new pathways and targets for interventions for MetS, diabetes, and atherosclerosis.


2021 ◽  
Author(s):  
Meenakshi Wadhwani

Hutchinson Gilford progeria Syndrome (HPGS) was first described by Jonathan Hutchinson Gilford in 1897 [1]. It is characterized by characteristic facies also described as plucked bird appearance. These are reported to occur due to denovo autosomal dominant mutation in Laminin A(LMNA) gene present on 1q21.1-1q 21.3 and are rarely inherited [2]. This is to report a rare case series of two children presenting with Hutchinson Gilford progeria with ocular manifestation.


2021 ◽  
Author(s):  
Giorgia Catarinella ◽  
Chiara Nicoletti ◽  
Andrea Bracaglia ◽  
Paola Procopio ◽  
Illari Salvatori ◽  
...  

Hutchinson-Gilford progeria syndrome (HGPS) is a rare, fatal disease caused by Lamin A mutation, leading to altered nuclear architecture, loss of perinuclear heterochromatin and deregulated gene expression. HGPS patients eventually die by coronary artery disease and cardiovascular alterations. However, how deregulated transcriptional networks at the cellular level impact on the systemic disease phenotype is currently unclear. We have performed a longitudinal genome-wide analysis of gene expression in primary HGPS fibroblasts from patients at two sequential stages of disease that revealed a progressive activation of Rho signaling and SerpinE1, also known as Plasminogen Activator Inhibitor (PAI-1). siRNA-mediated downregulation or pharmacological inhibition of SerpinE1 by TM5441 could revert key pathological features of HGPS in patient-derived fibroblasts, including re-activation of cell cycle progression, reduced DNA damage signaling, decreased expression of pro-fibrotic genes and recovery of mitochondrial defects. These effects were accompanied by reduced levels of Progerin and correction of nuclear abnormalities. These data point to SerpinE1 as a novel potential effector of HGPS pathogenesis and target for therapeutic interventions.


2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A308-A309
Author(s):  
Ali Tipu ◽  
Farhad Hasan ◽  
Michael Grimes

Abstract Introduction: Familial partial lipodystrophy (FPLD) is a rare genetic disorder characterized by loss of subcutaneous adipose tissue, mainly from the extremities and gluteal region. FPLD is associated with a variety of metabolic abnormalities including severe hypertriglyceridemia (HTG), insulin resistance (IR), and hepatic steatosis. We present a case of FPLD and summarize recent literature on the metabolic features and their management in patients with this rare disease. Case: A 44 year old female with medical history of Type 2 DM, hypertension, hypothyroidism and recurrent pancreatitis from severe HTG was referred to our clinic. She was diagnosed with Type 2 DM in her 30s. Over the ensuing years she had significant IR requiring increasing doses of concentrated insulin (up to 250 units/day). She reported progressive loss of subcutaneous fat from extremities in the preceding 2–3 years. She had recurrent pancreatitis, including a recent hospitalization with TG>8000 mg/dL. On examination, she had typical features of FPLD including loss of subcutaneous adipose tissue from upper and lower extremities including gluteal region, visible skeletal muscles and veins in the extremities, and neck and truncal obesity (Fig. 1). Family history was significant for similar physical and metabolic manifestations in her father and brother. For HTG, she is treated with fibrates and high intensity statin. We avoided the use of fish oil in the patient, because she did not feel well when she was previously on this. Results of the genetic testing are pending. Discussion: FPLD is rare, predominantly autosomal dominant, disorder characterized phenotypically by variable loss of subcutaneous fat and metabolically by severe HTG and insulin resistance. The severity of metabolic derangements is proportional to the degree of the lipodystrophy. The proposed mechanism is limited capacity of adipose tissue to store fat leading to ectopic fat deposition, lipotoxicity and vascular inflammation. Diagnosis is often clinical, especially the loss of subcutaneous fat in the extremities and signs of IR, and is confirmed by genetic testing. Dunnigan syndrome is the most common type of FPLD, which occurs from an autosomal dominant missense mutation in lamin A/C (LMNA). Gene mutations encoding for PPAR-gamma, Akt2, CIDEC, perilipin and the ZMPSTE 24 enzyme are much less common. Treatment of FPLD is challenging, and mostly focuses on managing the metabolic abnormalities. Recent evidence suggests that fish oil may in fact worsen HTG when the main defect driving increased TG is impaired chylomicron clearance, which our patient had on lipid NMR profile. Metreleptin, a human leptin analog, has recently been approved for the management of FPLD with evidence of improved metabolic abnormalities. Recent data also suggests that GLP1 agonists and SGLT2 inhibitors improved glycemic control and reduced daily insulin requirements.


2020 ◽  
Author(s):  
Elísabet Alcocer-Gómez ◽  
Beatriz Castejón-Vega ◽  
Jéssica Nuñez-Vasco ◽  
Débora Lendines-Cordero ◽  
José M. Navarro-Pando ◽  
...  

AbstractInflammation is a hallmark of aging and accelerated aging syndromes. In this context, inflammation has been associated to the pathophysiology of Hutchinson–Gilford progeria syndrome (HGPS). In this study, we report that progeroid skin fibroblasts and animal models present an hyperactivation of the NLRP3-inflammasome complex. High expression of NLRP3 and caspase 1 was also observed in skin fibroblasts from HGPS associated to the nuclei morphology. Lymphoblast from HGPS also showed increased basal levels of NLRP3 and caspase 1 independent to the induction from metabolic factors. Consistent with these results, Zmpste24−/− showed high expression of Nlrp3 and caspase 1 in heart, liver and kidney and reduced levels of Nlrc3, however these changes were not observed in other inflammasomes. We also show that pharmacological inhibition of NLRP3 using a direct NLRP3 inhibitor, MCC950, improved cellular phenotype, significantly extends the lifespan of these progeroid animals and reduced inflammasome-dependent inflammation. These findings suggest the NLRP3-inflammasome comples as a therapeutic approach for patients with HGPS.


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