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Antonisamy B, Shailesh H, Hani Y, Ahmed LHM, Noor S, Ahmed SY, Alfaki M, Muhayimana A, Jacob SS, Balayya SK, Soloviov O, Liu L, Mathew LS, Wang K, Tomei S, Al Massih A, Mathew R, Karim MY, Ramanjaneya M, Worgall S, Janahi IA. Sphingolipids in Childhood Asthma and Obesity (SOAP Study): A Protocol of a Cross-Sectional Study. Metabolites 2023; 13:1146. [PMID: 37999242 PMCID: PMC10673587 DOI: 10.3390/metabo13111146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 10/27/2023] [Accepted: 10/31/2023] [Indexed: 11/25/2023] Open
Abstract
Asthma and obesity are two of the most common chronic conditions in children and adolescents. There is increasing evidence that sphingolipid metabolism is altered in childhood asthma and is linked to airway hyperreactivity. Dysregulated sphingolipid metabolism is also reported in obesity. However, the functional link between sphingolipid metabolism, asthma, and obesity is not completely understood. This paper describes the protocol of an ongoing study on sphingolipids that aims to examine the pathophysiology of sphingolipids in childhood asthma and obesity. In addition, this study aims to explore the novel biomarkers through a comprehensive multi-omics approach including genomics, genome-wide DNA methylation, RNA-Seq, microRNA (miRNA) profiling, lipidomics, metabolomics, and cytokine profiling. This is a cross-sectional study aiming to recruit 440 children from different groups: children with asthma and normal weight (n = 100), asthma with overweight or obesity (n = 100), overweight or obesity (n = 100), normal weight (n = 70), and siblings of asthmatic children with normal weight, overweight, or obesity (n = 70). These participants will be recruited from the pediatric pulmonology, pediatric endocrinology, and general pediatric outpatient clinics at Sidra Medicine, Doha, Qatar. Information will be obtained from self-reported questionnaires on asthma, quality of life, food frequency (FFQ), and a 3-day food diary that are completed by the children and their parents. Clinical measurements will include anthropometry, blood pressure, biochemistry, bioelectrical impedance, and pulmonary function tests. Blood samples will be obtained for sphingolipid analysis, serine palmitoyltransferase (SPT) assay, whole-genome sequencing (WGS), genome-wide DNA methylation study, RNA-Seq, miRNA profiling, metabolomics, lipidomics, and cytokine analysis. Group comparisons of continuous outcome variables will be carried out by a one-way analysis of variance or the Kruskal-Wallis test using an appropriate pairwise multiple comparison test. The chi-squared test or a Fisher's exact test will be used to test the associations between categorical variables. Finally, multivariate analysis will be carried out to integrate the clinical data with multi-omics data. This study will help us to understand the role of dysregulated sphingolipid metabolism in obesity and asthma. In addition, the multi-omics data from the study will help to identify novel genetic and epigenetic signatures, inflammatory markers, and mechanistic pathways that link asthma and obesity in children. Furthermore, the integration of clinical and multi-omics data will help us to uncover the potential interactions between these diseases and to offer a new paradigm for the treatment of pediatric obesity-associated asthma.
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Affiliation(s)
- Belavendra Antonisamy
- Department of Pediatric Medicine, Sidra Medicine, Doha P.O. Box 26999, Qatar; (B.A.); (H.S.); (Y.H.); (L.H.M.A.); (S.N.); (S.Y.A.); (M.A.); (A.M.)
| | - Harshita Shailesh
- Department of Pediatric Medicine, Sidra Medicine, Doha P.O. Box 26999, Qatar; (B.A.); (H.S.); (Y.H.); (L.H.M.A.); (S.N.); (S.Y.A.); (M.A.); (A.M.)
| | - Yahya Hani
- Department of Pediatric Medicine, Sidra Medicine, Doha P.O. Box 26999, Qatar; (B.A.); (H.S.); (Y.H.); (L.H.M.A.); (S.N.); (S.Y.A.); (M.A.); (A.M.)
| | - Lina Hayati M. Ahmed
- Department of Pediatric Medicine, Sidra Medicine, Doha P.O. Box 26999, Qatar; (B.A.); (H.S.); (Y.H.); (L.H.M.A.); (S.N.); (S.Y.A.); (M.A.); (A.M.)
| | - Safa Noor
- Department of Pediatric Medicine, Sidra Medicine, Doha P.O. Box 26999, Qatar; (B.A.); (H.S.); (Y.H.); (L.H.M.A.); (S.N.); (S.Y.A.); (M.A.); (A.M.)
| | - Salma Yahya Ahmed
- Department of Pediatric Medicine, Sidra Medicine, Doha P.O. Box 26999, Qatar; (B.A.); (H.S.); (Y.H.); (L.H.M.A.); (S.N.); (S.Y.A.); (M.A.); (A.M.)
| | - Mohamed Alfaki
- Department of Pediatric Medicine, Sidra Medicine, Doha P.O. Box 26999, Qatar; (B.A.); (H.S.); (Y.H.); (L.H.M.A.); (S.N.); (S.Y.A.); (M.A.); (A.M.)
| | - Abidan Muhayimana
- Department of Pediatric Medicine, Sidra Medicine, Doha P.O. Box 26999, Qatar; (B.A.); (H.S.); (Y.H.); (L.H.M.A.); (S.N.); (S.Y.A.); (M.A.); (A.M.)
| | - Shana Sunny Jacob
- Analytical Chemistry Core, Advanced Diagnostic Core Facilities, Sidra Medicine, Doha P.O. Box 26999, Qatar; (S.S.J.); (S.K.B.)
| | - Saroja Kotegar Balayya
- Analytical Chemistry Core, Advanced Diagnostic Core Facilities, Sidra Medicine, Doha P.O. Box 26999, Qatar; (S.S.J.); (S.K.B.)
| | - Oleksandr Soloviov
- Clinical Genomics Laboratory, Integrated Genomics Services, Sidra Medicine, Doha P.O. Box 26999, Qatar; (O.S.); (L.L.); (L.S.M.); (K.W.)
| | - Li Liu
- Clinical Genomics Laboratory, Integrated Genomics Services, Sidra Medicine, Doha P.O. Box 26999, Qatar; (O.S.); (L.L.); (L.S.M.); (K.W.)
| | - Lisa Sara Mathew
- Clinical Genomics Laboratory, Integrated Genomics Services, Sidra Medicine, Doha P.O. Box 26999, Qatar; (O.S.); (L.L.); (L.S.M.); (K.W.)
| | - Kun Wang
- Clinical Genomics Laboratory, Integrated Genomics Services, Sidra Medicine, Doha P.O. Box 26999, Qatar; (O.S.); (L.L.); (L.S.M.); (K.W.)
| | - Sara Tomei
- Omics Core, Integrated Genomics Services, Sidra Medicine, Doha P.O. Box 26999, Qatar; (S.T.); (A.A.M.); (R.M.)
| | - Alia Al Massih
- Omics Core, Integrated Genomics Services, Sidra Medicine, Doha P.O. Box 26999, Qatar; (S.T.); (A.A.M.); (R.M.)
| | - Rebecca Mathew
- Omics Core, Integrated Genomics Services, Sidra Medicine, Doha P.O. Box 26999, Qatar; (S.T.); (A.A.M.); (R.M.)
| | - Mohammed Yousuf Karim
- Department of Pathology, Sidra Medicine, Doha P.O. Box 26999, Qatar;
- College of Medicine, Qatar University, Doha P.O. Box 2713, Qatar
| | - Manjunath Ramanjaneya
- Qatar Metabolic Institute, Hamad Medical Corporation, Doha P.O. Box 3050, Qatar;
- Translational Research Institute, Hamad Medical Corporation, Doha P.O. Box 3050, Qatar
| | - Stefan Worgall
- Department of Pediatrics, Weill Cornell Medicine, New York, NY 10021, USA;
| | - Ibrahim A. Janahi
- Department of Pediatric Medicine, Sidra Medicine, Doha P.O. Box 26999, Qatar; (B.A.); (H.S.); (Y.H.); (L.H.M.A.); (S.N.); (S.Y.A.); (M.A.); (A.M.)
- Department of Pediatrics, Weill Cornell Medicine-Qatar, Doha P.O. Box 24144, Qatar
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2
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Santilli F, Fabrizi J, Martellucci S, Santacroce C, Iorio E, Pisanu ME, Chirico M, Lancia L, Pulcini F, Manganelli V, Sorice M, Delle Monache S, Mattei V. Lipid rafts mediate multilineage differentiation of human dental pulp-derived stem cells (DPSCs). Front Cell Dev Biol 2023; 11:1274462. [PMID: 38020931 PMCID: PMC10665896 DOI: 10.3389/fcell.2023.1274462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 10/23/2023] [Indexed: 12/01/2023] Open
Abstract
Cell outer membranes contain glycosphingolipids and protein receptors, which are integrated into glycoprotein domains, known as lipid rafts, which are involved in a variety of cellular processes, including receptor-mediated signal transduction and cellular differentiation process. In this study, we analyzed the lipidic composition of human Dental Pulp-Derived Stem Cells (DPSCs), and the role of lipid rafts during the multilineage differentiation process. The relative quantification of lipid metabolites in the organic fraction of DPSCs, performed by Nuclear Magnetic Resonance (NMR) spectroscopy, showed that mono-unsaturated fatty acids (MUFAs) were the most representative species in the total pool of acyl chains, compared to polyunsatured fatty acids (PUFAs). In addition, the stimulation of DPSCs with different culture media induces a multilineage differentiation process, determining changes in the gangliosides pattern. To understand the functional role of lipid rafts during multilineage differentiation, DPSCs were pretreated with a typical lipid raft affecting agent (MβCD). Subsequently, DPSCs were inducted to differentiate into osteoblast, chondroblast and adipoblast cells with specific media. We observed that raft-affecting agent MβCD prevented AKT activation and the expression of lineage-specific mRNA such as OSX, PPARγ2, and SOX9 during multilineage differentiation. Moreover, this compound significantly prevented the tri-lineage differentiation induced by specific stimuli, indicating that lipid raft integrity is essential for DPSCs differentiation. These results suggest that lipid rafts alteration may affect the signaling pathway activated, preventing multilineage differentiation.
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Affiliation(s)
- Francesca Santilli
- Biomedicine and Advanced Technologies Rieti Center, “Sabina Universitas”, Rieti, Italy
| | - Jessica Fabrizi
- Biomedicine and Advanced Technologies Rieti Center, “Sabina Universitas”, Rieti, Italy
- Department of Experimental Medicine, “Sapienza” University of Rome, Rome, Italy
| | - Stefano Martellucci
- Biomedicine and Advanced Technologies Rieti Center, “Sabina Universitas”, Rieti, Italy
| | - Costantino Santacroce
- Biomedicine and Advanced Technologies Rieti Center, “Sabina Universitas”, Rieti, Italy
| | - Egidio Iorio
- High Resolution NMR Unit, Core Facilities, Istituto Superiore di Sanità, Rome, Italy
| | - Maria Elena Pisanu
- High Resolution NMR Unit, Core Facilities, Istituto Superiore di Sanità, Rome, Italy
| | - Mattea Chirico
- High Resolution NMR Unit, Core Facilities, Istituto Superiore di Sanità, Rome, Italy
| | - Loreto Lancia
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, L’Aquila, Italy
| | - Fanny Pulcini
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, L’Aquila, Italy
| | - Valeria Manganelli
- Department of Experimental Medicine, “Sapienza” University of Rome, Rome, Italy
| | - Maurizio Sorice
- Department of Experimental Medicine, “Sapienza” University of Rome, Rome, Italy
| | - Simona Delle Monache
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, L’Aquila, Italy
| | - Vincenzo Mattei
- Dipartimento di Scienze della Vita, della Salute e delle Professioni Sanitarie, Link Campus University, Rome, Italy
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Mannully CT, Bruck-Haimson R, Zacharia A, Orih P, Shehadeh A, Saidemberg D, Kogan NM, Alfandary S, Serruya R, Dagan A, Petit I, Moussaieff A. Lipid desaturation regulates the balance between self-renewal and differentiation in mouse blastocyst-derived stem cells. Cell Death Dis 2022; 13:1027. [PMID: 36477438 PMCID: PMC9729213 DOI: 10.1038/s41419-022-05263-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 08/31/2022] [Accepted: 09/13/2022] [Indexed: 12/13/2022]
Abstract
Stem cells are defined by their ability to self-renew and differentiate, both shown in multiple studies to be regulated by metabolic processes. To decipher metabolic signatures of self-renewal in blastocyst-derived stem cells, we compared early differentiating embryonic stem cells (ESCs) and their extra-embryonic counterparts, trophoblast (T)SCs to their self-renewing counterparts. A metabolomics analysis pointed to the desaturation of fatty acyl chains as a metabolic signature of differentiating blastocyst-derived SCs via the upregulation of delta-6 desaturase (D6D; FADS2) and delta-5 desaturase (D5D; FADS1), key enzymes in the biosynthesis of polyunsaturated fatty acids (PUFAs). The inhibition of D6D or D5D by specific inhibitors or SiRNA retained stemness in ESCs and TSCs, and attenuated endoplasmic reticulum (ER) stress-related apoptosis. D6D inhibition in ESCs upregulated stearoyl-CoA desaturase-1 (Scd1), essential to maintain ER homeostasis. In TSCs, however, D6D inhibition downregulated Scd1. TSCs show higher Scd1 mRNA expression and high levels of monounsaturated fatty acyl chain products in comparison to ESCs. The addition of oleic acid, the product of Scd1 (essential for ESCs), to culture medium, was detrimental to TSCs. Interestingly, TSCs express a high molecular mass variant of Scd1 protein, hardly expressed by ESCs. Taken together, our data suggest that lipid desaturation is a metabolic regulator of the balance between differentiation and self-renewal of ESCs and TSCs. They point to lipid polydesaturation as a driver of differentiation in both cell types. Monounsaturated fatty acids (MUFAs), essential for ESCs are detrimental to TSCs.
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Affiliation(s)
- Chanchal Thomas Mannully
- grid.9619.70000 0004 1937 0538The Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Reut Bruck-Haimson
- grid.9619.70000 0004 1937 0538The Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Anish Zacharia
- grid.9619.70000 0004 1937 0538The Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Paul Orih
- grid.9619.70000 0004 1937 0538The Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Alaa Shehadeh
- grid.9619.70000 0004 1937 0538The Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Daniel Saidemberg
- grid.9619.70000 0004 1937 0538The Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Natalya M. Kogan
- grid.9619.70000 0004 1937 0538The Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Sivan Alfandary
- grid.9619.70000 0004 1937 0538The Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Raphael Serruya
- grid.9619.70000 0004 1937 0538The Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Arie Dagan
- grid.9619.70000 0004 1937 0538The Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Isabelle Petit
- grid.465261.20000 0004 1793 5929Sorbonne Université, Inserm, Centre de Recherche Saint-Antoine, CRSA, Paris, France
| | - Arieh Moussaieff
- grid.9619.70000 0004 1937 0538The Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
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4
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Voelkel-Johnson C. Sphingolipids in embryonic development, cell cycle regulation, and stemness - Implications for polyploidy in tumors. Semin Cancer Biol 2022; 81:206-219. [PMID: 33429049 PMCID: PMC8263803 DOI: 10.1016/j.semcancer.2020.12.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 12/26/2020] [Accepted: 12/30/2020] [Indexed: 12/12/2022]
Abstract
The aberrant biology of polyploid giant cancer cells (PGCC) includes dysregulation of the cell cycle, induction of stress responses, and dedifferentiation, all of which are likely accompanied by adaptations in biophysical properties and metabolic activity. Sphingolipids are the second largest class of membrane lipids and play important roles in many aspects of cell biology that are potentially relevant to polyploidy. We have recently shown that the function of the sphingolipid enzyme acid ceramidase (ASAH1) is critical for the ability of PGCC to generate progeny by depolyploidization but mechanisms by which sphingolipids contribute to polyploidy and generation of offspring with stem-like properties remain elusive. This review discusses the role of sphingolipids during embryonic development, cell cycle regulation, and stem cells in an effort to highlight parallels to polyploidy.
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Affiliation(s)
- Christina Voelkel-Johnson
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, USA.
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5
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Bispo DSC, Jesus CSH, Marques IMC, Romek KM, Oliveira MB, Mano JF, Gil AM. Metabolomic Applications in Stem Cell Research: a Review. Stem Cell Rev Rep 2021; 17:2003-2024. [PMID: 34131883 DOI: 10.1007/s12015-021-10193-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/24/2021] [Indexed: 12/17/2022]
Abstract
This review describes the use of metabolomics to study stem cell (SC) characteristics and function, excluding SCs in cancer research, suited to a fully dedicated text. The interest in employing metabolomics in SC research has consistently grown and emphasis is, here, given to developments reported in the past five years. This text informs on the existing methodologies and their complementarity regarding the information provided, comprising untargeted/targeted approaches, which couple mass spectrometry or nuclear magnetic resonance spectroscopy with multivariate analysis (and, in some cases, pathway analysis and integration with other omics), and more specific analytical approaches, namely isotope tracing to highlight particular metabolic pathways, or in tandem microscopic strategies to pinpoint characteristics within a single cell. The bulk of this review covers the existing applications in various aspects of mesenchymal SC behavior, followed by pluripotent and neural SCs, with a few reports addressing other SC types. Some of the central ideas investigated comprise the metabolic/biological impacts of different tissue/donor sources and differentiation conditions, including the importance of considering 3D culture environments, mechanical cues and/or media enrichment to guide differentiation into specific lineages. Metabolomic analysis has considered cell endometabolomes and exometabolomes (fingerprinting and footprinting, respectively), having measured both lipid species and polar metabolites involved in a variety of metabolic pathways. This review clearly demonstrates the current enticing promise of metabolomics in significantly contributing towards a deeper knowledge on SC behavior, and the discovery of new biomarkers of SC function with potential translation to in vivo clinical practice.
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Affiliation(s)
- Daniela S C Bispo
- Department of Chemistry, CICECO - Aveiro Institute of Materials (CICECO/UA), University of Aveiro, Campus Universitario de Santiago, 3810-193, Aveiro, Portugal
| | - Catarina S H Jesus
- Department of Chemistry, CICECO - Aveiro Institute of Materials (CICECO/UA), University of Aveiro, Campus Universitario de Santiago, 3810-193, Aveiro, Portugal
| | - Inês M C Marques
- Department of Chemistry, CICECO - Aveiro Institute of Materials (CICECO/UA), University of Aveiro, Campus Universitario de Santiago, 3810-193, Aveiro, Portugal
| | - Katarzyna M Romek
- Department of Chemistry, CICECO - Aveiro Institute of Materials (CICECO/UA), University of Aveiro, Campus Universitario de Santiago, 3810-193, Aveiro, Portugal
| | - Mariana B Oliveira
- Department of Chemistry, CICECO - Aveiro Institute of Materials (CICECO/UA), University of Aveiro, Campus Universitario de Santiago, 3810-193, Aveiro, Portugal
| | - João F Mano
- Department of Chemistry, CICECO - Aveiro Institute of Materials (CICECO/UA), University of Aveiro, Campus Universitario de Santiago, 3810-193, Aveiro, Portugal
| | - Ana M Gil
- Department of Chemistry, CICECO - Aveiro Institute of Materials (CICECO/UA), University of Aveiro, Campus Universitario de Santiago, 3810-193, Aveiro, Portugal.
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Clémot M, Sênos Demarco R, Jones DL. Lipid Mediated Regulation of Adult Stem Cell Behavior. Front Cell Dev Biol 2020; 8:115. [PMID: 32185173 PMCID: PMC7058546 DOI: 10.3389/fcell.2020.00115] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 02/11/2020] [Indexed: 12/18/2022] Open
Abstract
Adult stem cells constitute an important reservoir of self-renewing progenitor cells and are crucial for maintaining tissue and organ homeostasis. The capacity of stem cells to self-renew or differentiate can be attributed to distinct metabolic states, and it is now becoming apparent that metabolism plays instructive roles in stem cell fate decisions. Lipids are an extremely vast class of biomolecules, with essential roles in energy homeostasis, membrane structure and signaling. Imbalances in lipid homeostasis can result in lipotoxicity, cell death and diseases, such as cardiovascular disease, insulin resistance and diabetes, autoimmune disorders and cancer. Therefore, understanding how lipid metabolism affects stem cell behavior offers promising perspectives for the development of novel approaches to control stem cell behavior either in vitro or in patients, by modulating lipid metabolic pathways pharmacologically or through diet. In this review, we will first address how recent progress in lipidomics has created new opportunities to uncover stem-cell specific lipidomes. In addition, genetic and/or pharmacological modulation of lipid metabolism have shown the involvement of specific pathways, such as fatty acid oxidation (FAO), in regulating adult stem cell behavior. We will describe and compare findings obtained in multiple stem cell models in order to provide an assessment on whether unique lipid metabolic pathways may commonly regulate stem cell behavior. We will then review characterized and potential molecular mechanisms through which lipids can affect stem cell-specific properties, including self-renewal, differentiation potential or interaction with the niche. Finally, we aim to summarize the current knowledge of how alterations in lipid homeostasis that occur as a consequence of changes in diet, aging or disease can impact stem cells and, consequently, tissue homeostasis and repair.
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Affiliation(s)
- Marie Clémot
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, United States
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA, United States
| | - Rafael Sênos Demarco
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, United States
| | - D. Leanne Jones
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, United States
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA, United States
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, United States
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7
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Crivelli SM, Giovagnoni C, Visseren L, Scheithauer AL, de Wit N, den Hoedt S, Losen M, Mulder MT, Walter J, de Vries HE, Bieberich E, Martinez-Martinez P. Sphingolipids in Alzheimer's disease, how can we target them? Adv Drug Deliv Rev 2020; 159:214-231. [PMID: 31911096 DOI: 10.1016/j.addr.2019.12.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 10/09/2019] [Accepted: 12/31/2019] [Indexed: 01/06/2023]
Abstract
Altered levels of sphingolipids and their metabolites in the brain, and the related downstream effects on neuronal homeostasis and the immune system, provide a framework for understanding mechanisms in neurodegenerative disorders and for developing new intervention strategies. In this review we will discuss: the metabolites of sphingolipids that function as second messengers; and functional aberrations of the pathway resulting in Alzheimer's disease (AD) pathophysiology. Focusing on the central product of the sphingolipid pathway ceramide, we describ approaches to pharmacologically decrease ceramide levels in the brain and we argue on how the sphingolipid pathway may represent a new framework for developing novel intervention strategies in AD. We also highlight the possible use of clinical and non-clinical drugs to modulate the sphingolipid pathway and sphingolipid-related biological cascades.
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8
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Ávila-García R, Valdés J, Jáuregui-Wade JM, Ayala-Sumuano JT, Cerbón-Solórzano J. The metabolic pathway of sphingolipids biosynthesis and signaling in Entamoeba histolytica. Biochem Biophys Res Commun 2019; 522:574-579. [PMID: 31785811 DOI: 10.1016/j.bbrc.2019.11.116] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Accepted: 11/18/2019] [Indexed: 10/25/2022]
Abstract
Sphingolipids (SLs) synthesis involves a complex metabolic pathway occurring between the endoplasmic reticulum (ER) and Golgi apparatus, generating ceramide synthesis and complex lipids, respectively. Here we show that E. histolytica, apparently lacking cellular organelles (ER and Golgi apparatus), synthesizes a wide variety of sphingolipid subspecies, being particularly abundant those of long-chain fatty acids. In silico analysis showed five putative genes coding for ceramide synthases (CerS), all of them coding for proteins containing the TLC domain, a region conserved in CerS of multiple organisms. These genes are abundantly expressed in different growth phases. Silencing and overexpression of CerS C4M4U4 (the closest homolog of human CerS 2 and 3) demonstrated its involvement in the synthesis of ceramide. Additionally, we identify C4M4U4, SMS2 and PKC (α, βII) proteins and their subcellular localization of E. histolytica, suggesting that these subcellular compartments might be involved in the biosynthesis and signaling pathway of sphingolipids, and evidencing different sphingolipid synthesis pathways in Entamoeba.
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Affiliation(s)
| | - Jesús Valdés
- Department of Biochemistry, CINVESTAV-IPN, Ciudad de México, Mexico
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9
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Torres-Sánchez M, Gower DJ, Alvarez-Ponce D, Creevey CJ, Wilkinson M, San Mauro D. What lies beneath? Molecular evolution during the radiation of caecilian amphibians. BMC Genomics 2019; 20:354. [PMID: 31072350 PMCID: PMC6507065 DOI: 10.1186/s12864-019-5694-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 04/15/2019] [Indexed: 12/12/2022] Open
Abstract
Background Evolution leaves an imprint in species through genetic change. At the molecular level, evolutionary changes can be explored by studying ratios of nucleotide substitutions. The interplay among molecular evolution, derived phenotypes, and ecological ranges can provide insights into adaptive radiations. Caecilians (order Gymnophiona), probably the least known of the major lineages of vertebrates, are limbless tropical amphibians, with adults of most species burrowing in soils (fossoriality). This enigmatic order of amphibians are very distinct phenotypically from other extant amphibians and likely from the ancestor of Lissamphibia, but little to nothing is known about the molecular changes underpinning their radiation. We hypothesised that colonization of various depths of tropical soils and of freshwater habitats presented new ecological opportunities to caecilians. Results A total of 8540 candidate groups of orthologous genes from transcriptomic data of five species of caecilian amphibians and the genome of the frog Xenopus tropicalis were analysed in order to investigate the genetic machinery behind caecilian diversification. We found a total of 168 protein-coding genes with signatures of positive selection at different evolutionary times during the radiation of caecilians. The majority of these genes were related to functional elements of the cell membrane and extracellular matrix with expression in several different tissues. The first colonization of the tropical soils was connected to the largest number of protein-coding genes under positive selection in our analysis. From the results of our study, we highlighted molecular changes in genes involved in perception, reduction-oxidation processes, and aging that likely were involved in the adaptation to different soil strata. Conclusions The genes inferred to have been under positive selection provide valuable insights into caecilian evolution, potentially underpin adaptations of caecilians to their extreme environments, and contribute to a better understanding of fossorial adaptations and molecular evolution in vertebrates. Electronic supplementary material The online version of this article (10.1186/s12864-019-5694-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- María Torres-Sánchez
- Department of Biodiversity, Ecology and Evolution, Complutense University of Madrid, 28040, Madrid, Spain. .,Present address: Department of Neuroscience, Spinal Cord and Brain Injury Research Center & Ambystoma Genetic Stock Center, University of Kentucky, Lexington, KY, 40536, USA.
| | - David J Gower
- Department of Life Sciences, The Natural History Museum, London, SW7 5BD, UK
| | | | - Christopher J Creevey
- Institute for Global Food Security, Queen's University Belfast, University Road, Belfast, BT7 1NN, Northern Ireland, UK
| | - Mark Wilkinson
- Department of Life Sciences, The Natural History Museum, London, SW7 5BD, UK
| | - Diego San Mauro
- Department of Biodiversity, Ecology and Evolution, Complutense University of Madrid, 28040, Madrid, Spain
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10
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Gencer S, Oleinik N, Kim J, Panneer Selvam S, De Palma R, Dany M, Nganga R, Thomas RJ, Senkal CE, Howe PH, Ogretmen B. TGF-β receptor I/II trafficking and signaling at primary cilia are inhibited by ceramide to attenuate cell migration and tumor metastasis. Sci Signal 2017; 10:eaam7464. [PMID: 29066540 PMCID: PMC5818989 DOI: 10.1126/scisignal.aam7464] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Signaling by the transforming growth factor-β (TGF-β) receptors I and II (TβRI/II) and the primary cilia-localized sonic hedgehog (Shh) pathway promote cell migration and, consequently, tumor metastasis. In contrast, the sphingolipid ceramide inhibits cell proliferation and tumor metastasis. We investigated whether ceramide metabolism inhibited TβRI/II trafficking to primary cilia to attenuate cross-talk between TβRI/II and the Shh pathway. We found that ceramide synthase 4 (CerS4)-generated ceramide stabilized the association between TβRI and the inhibitory factor Smad7, which limited the trafficking of TβRI/II to primary cilia. Expression of a mutant TβRI that signals but does not interact with Smad7 prevented the CerS4-mediated inhibition of migration in various cancer cells. Genetic deletion or knockdown of CerS4 prevented the formation of the Smad7-TβRI inhibitory complex and increased the association between TβRI and the transporter Arl6 through a previously unknown cilia-targeting signal (Ala31Thr32Ala33Leu34Gln35) in TβRI. Mutating the cilia-targeting signal abolished the trafficking of TβRI to the primary cilia. Localization of TβRI to primary cilia activated a key mediator of Shh signaling, Smoothened (Smo), which stimulated cellular migration and invasion. TβRI-Smo cross-talk at the cilia in CerS4-deficient 4T1 mammary cancer cells induced liver metastasis from orthotopic allografts in both wild-type and CerS4-deficient mice, which was prevented by overexpression of Smad7 or knockdown of intraflagellar transport protein 88 (IFT88). Overall, these data reveal a ceramide-dependent mechanism that suppresses cell migration and invasion by restricting TβRI/II-Shh signaling selectively at the plasma membrane of the primary cilium.
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Affiliation(s)
- Salih Gencer
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 125 Ashley Avenue, Charleston, SC 29425, USA
- Hollings Cancer Center, 86 Jonathan Lucas Street, Charleston, SC 29425, USA
| | - Natalia Oleinik
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 125 Ashley Avenue, Charleston, SC 29425, USA
- Hollings Cancer Center, 86 Jonathan Lucas Street, Charleston, SC 29425, USA
| | - Jisun Kim
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 125 Ashley Avenue, Charleston, SC 29425, USA
- Hollings Cancer Center, 86 Jonathan Lucas Street, Charleston, SC 29425, USA
| | - Shanmugam Panneer Selvam
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 125 Ashley Avenue, Charleston, SC 29425, USA
- Hollings Cancer Center, 86 Jonathan Lucas Street, Charleston, SC 29425, USA
| | - Ryan De Palma
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 125 Ashley Avenue, Charleston, SC 29425, USA
- Hollings Cancer Center, 86 Jonathan Lucas Street, Charleston, SC 29425, USA
| | - Mohammed Dany
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 125 Ashley Avenue, Charleston, SC 29425, USA
- Hollings Cancer Center, 86 Jonathan Lucas Street, Charleston, SC 29425, USA
| | - Rose Nganga
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 125 Ashley Avenue, Charleston, SC 29425, USA
- Hollings Cancer Center, 86 Jonathan Lucas Street, Charleston, SC 29425, USA
| | - Raquela J Thomas
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 125 Ashley Avenue, Charleston, SC 29425, USA
- Hollings Cancer Center, 86 Jonathan Lucas Street, Charleston, SC 29425, USA
| | - Can E Senkal
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 125 Ashley Avenue, Charleston, SC 29425, USA
- Hollings Cancer Center, 86 Jonathan Lucas Street, Charleston, SC 29425, USA
| | - Philip H Howe
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 125 Ashley Avenue, Charleston, SC 29425, USA
- Hollings Cancer Center, 86 Jonathan Lucas Street, Charleston, SC 29425, USA
| | - Besim Ogretmen
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 125 Ashley Avenue, Charleston, SC 29425, USA.
- Hollings Cancer Center, 86 Jonathan Lucas Street, Charleston, SC 29425, USA
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11
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Glycosphingolipid-Protein Interaction in Signal Transduction. Int J Mol Sci 2016; 17:ijms17101732. [PMID: 27754465 PMCID: PMC5085762 DOI: 10.3390/ijms17101732] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 10/04/2016] [Accepted: 10/10/2016] [Indexed: 12/31/2022] Open
Abstract
Glycosphingolipids (GSLs) are a class of ceramide-based glycolipids essential for embryo development in mammals. The synthesis of specific GSLs depends on the expression of distinctive sets of GSL synthesizing enzymes that is tightly regulated during development. Several reports have described how cell surface receptors can be kept in a resting state or activate alternative signalling events as a consequence of their interaction with GSLs. Specific GSLs, indeed, interface with specific protein domains that are found in signalling molecules and which act as GSL sensors to modify signalling responses. The regulation exerted by GSLs on signal transduction is orthogonal to the ligand–receptor axis, as it usually does not directly interfere with the ligand binding to receptors. Due to their properties of adjustable production and orthogonal action on receptors, GSLs add a new dimension to the control of the signalling in development. GSLs can, indeed, dynamically influence progenitor cell response to morphogenetic stimuli, resulting in alternative differentiation fates. Here, we review the available literature on GSL–protein interactions and their effects on cell signalling and development.
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12
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Wockner LF, Morris CP, Noble EP, Lawford BR, Whitehall VLJ, Young RM, Voisey J. Brain-specific epigenetic markers of schizophrenia. Transl Psychiatry 2015; 5:e680. [PMID: 26575221 PMCID: PMC5068768 DOI: 10.1038/tp.2015.177] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 07/22/2015] [Accepted: 07/27/2015] [Indexed: 02/07/2023] Open
Abstract
Epigenetics plays a crucial role in schizophrenia susceptibility. In a previous study, we identified over 4500 differentially methylated sites in prefrontal cortex (PFC) samples from schizophrenia patients. We believe this was the first genome-wide methylation study performed on human brain tissue using the Illumina Infinium HumanMethylation450 Bead Chip. To understand the biological significance of these results, we sought to identify a smaller number of differentially methylated regions (DMRs) of more functional relevance compared with individual differentially methylated sites. Since our schizophrenia whole genome methylation study was performed, another study analysing two separate data sets of post-mortem tissue in the PFC from schizophrenia patients has been published. We analysed all three data sets using the bumphunter function found in the Bioconductor package minfi to identify regions that are consistently differentially methylated across distinct cohorts. We identified seven regions that are consistently differentially methylated in schizophrenia, despite considerable heterogeneity in the methylation profiles of patients with schizophrenia. The regions were near CERS3, DPPA5, PRDM9, DDX43, REC8, LY6G5C and a region on chromosome 10. Of particular interest is PRDM9 which encodes a histone methyltransferase that is essential for meiotic recombination and is known to tag genes for epigenetic transcriptional activation. These seven DMRs are likely to be key epigenetic factors in the aetiology of schizophrenia and normal brain neurodevelopment.
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Affiliation(s)
- L F Wockner
- Queensland Institute of Medical Research, Brisbane, QLD, Australia
| | - C P Morris
- Department of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - E P Noble
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, USA
| | - B R Lawford
- Department of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - V L J Whitehall
- Queensland Institute of Medical Research, Brisbane, QLD, Australia
| | - R M Young
- Department of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - J Voisey
- Department of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia,Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, 2 George Street, Kelvin Grove, QLD 4000, Australia. E-mail:
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13
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Campos AM, Maciel E, Moreira ASP, Sousa B, Melo T, Domingues P, Curado L, Antunes B, Domingues MRM, Santos F. Lipidomics of Mesenchymal Stromal Cells: Understanding the Adaptation of Phospholipid Profile in Response to Pro-Inflammatory Cytokines. J Cell Physiol 2015; 231:1024-32. [DOI: 10.1002/jcp.25191] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 09/10/2015] [Indexed: 12/22/2022]
Affiliation(s)
- Ana Margarida Campos
- Mass Spectrometry Centre, QOPNA; Department of Chemistry; University of Aveiro; Aveiro Portugal
| | - Elisabete Maciel
- Mass Spectrometry Centre, QOPNA; Department of Chemistry; University of Aveiro; Aveiro Portugal
| | - Ana S. P. Moreira
- Mass Spectrometry Centre, QOPNA; Department of Chemistry; University of Aveiro; Aveiro Portugal
| | - Bebiana Sousa
- Mass Spectrometry Centre, QOPNA; Department of Chemistry; University of Aveiro; Aveiro Portugal
| | - Tânia Melo
- Mass Spectrometry Centre, QOPNA; Department of Chemistry; University of Aveiro; Aveiro Portugal
| | - Pedro Domingues
- Mass Spectrometry Centre, QOPNA; Department of Chemistry; University of Aveiro; Aveiro Portugal
| | - Liliana Curado
- Cell2B Advanced Therapeutics SA; Biocant Park Núcleo 04 Lote 4 A; Cantanhede Portugal
| | - Brígida Antunes
- Cell2B Advanced Therapeutics SA; Biocant Park Núcleo 04 Lote 4 A; Cantanhede Portugal
| | - M. Rosário M. Domingues
- Mass Spectrometry Centre, QOPNA; Department of Chemistry; University of Aveiro; Aveiro Portugal
| | - Francisco Santos
- Cell2B Advanced Therapeutics SA; Biocant Park Núcleo 04 Lote 4 A; Cantanhede Portugal
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14
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Sun Y, Florer J, Mayhew CN, Jia Z, Zhao Z, Xu K, Ran H, Liou B, Zhang W, Setchell KDR, Gu J, Grabowski GA. Properties of neurons derived from induced pluripotent stem cells of Gaucher disease type 2 patient fibroblasts: potential role in neuropathology. PLoS One 2015; 10:e0118771. [PMID: 25822147 PMCID: PMC4378893 DOI: 10.1371/journal.pone.0118771] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 01/06/2015] [Indexed: 11/30/2022] Open
Abstract
Gaucher disease (GD) is caused by insufficient activity of acid β-glucosidase (GCase) resulting from mutations in GBA1. To understand the pathogenesis of the neuronopathic GD, induced pluripotent stem cells (iPSCs) were generated from fibroblasts isolated from three GD type 2 (GD2) and 2 unaffected (normal and GD carrier) individuals. The iPSCs were converted to neural precursor cells (NPCs) which were further differentiated into neurons. Parental GD2 fibroblasts as well as iPSCs, NPCs, and neurons had similar degrees of GCase deficiency. Lipid analyses showed increases of glucosylsphingosine and glucosylceramide in the GD2 cells. In addition, GD2 neurons showed increased α-synuclein protein compared to control neurons. Whole cell patch-clamping of the GD2 and control iPSCs-derived neurons demonstrated excitation characteristics of neurons, but intriguingly, those from GD2 exhibited consistently less negative resting membrane potentials with various degree of reduction in action potential amplitudes, sodium and potassium currents. Culture of control neurons in the presence of the GCase inhibitor (conduritol B epoxide) recapitulated these findings, providing a functional link between decreased GCase activity in GD and abnormal neuronal electrophysiological properties. To our knowledge, this study is first to report abnormal electrophysiological properties in GD2 iPSC-derived neurons that may underlie the neuropathic phenotype in Gaucher disease.
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Affiliation(s)
- Ying Sun
- Division of Human Genetics, Cincinnati Children’s Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- * E-mail:
| | - Jane Florer
- Division of Human Genetics, Cincinnati Children’s Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Christopher N. Mayhew
- Division of Developmental Biology, Cincinnati Children’s Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Zhanfeng Jia
- Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China
| | - Zhiying Zhao
- Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China
| | - Kui Xu
- Division of Human Genetics, Cincinnati Children’s Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Huimin Ran
- Division of Human Genetics, Cincinnati Children’s Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Benjamin Liou
- Division of Human Genetics, Cincinnati Children’s Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Wujuan Zhang
- Division of Pathology and Laboratory Medicine, Cincinnati Children’s Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Kenneth D. R. Setchell
- Division of Pathology and Laboratory Medicine, Cincinnati Children’s Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Jianguo Gu
- Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Gregory A. Grabowski
- Division of Human Genetics, Cincinnati Children’s Hospital Research Foundation, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Synageva BioPharma Corp., Lexington, Massachusetts, United States of America
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15
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Liu YS, Lee OK. In search of the pivot point of mechanotransduction: mechanosensing of stem cells. Cell Transplant 2014; 23:1-11. [PMID: 24439034 DOI: 10.3727/096368912x659925] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Stem cells are undifferentiated cells with the ability to self-renew and to differentiate into diverse specialized cell types; hence, they have great potential in tissue engineering and cell therapies. In addition to biochemical regulation, the physical properties of the microenvironments, such as scaffold topography, substrate stiffness, and mechanical forces, including fluid shear stress, compression, and tensile strain, can also regulate the proliferation and differentiation of stem cells. Upon physical stimuli, cytoskeleton rearrangements are expected to counterbalance the extracellular mechanical forces, trigger signaling cascades, and eventually cause epigenetic modifications. This article mainly focuses on the mechanosensing, which is the upstream event of stem cell mechanotransduction and the downstream one of physical stimuli. Putative mechanosensors such as ion channels, integrins, and cell membrane as well as primary cilia are discussed. Because mechanical environment is an important stem cell niche, identification of mechanosensors not only can elucidate the mechanisms of mechanotransduction and fate commitments but also bring new prospects of the mechanical control as well as drug development for clinical application.
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Affiliation(s)
- Yi-Shiuan Liu
- Stem Cell Research Center, National Yang-Ming University, Taipei, Taiwan
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16
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Mercken EM, Mitchell SJ, Martin‐Montalvo A, Minor RK, Almeida M, Gomes AP, Scheibye‐Knudsen M, Palacios HH, Licata JJ, Zhang Y, Becker KG, Khraiwesh H, González‐Reyes JA, Villalba JM, Baur JA, Elliott P, Westphal C, Vlasuk GP, Ellis JL, Sinclair DA, Bernier M, Cabo R. SRT2104 extends survival of male mice on a standard diet and preserves bone and muscle mass. Aging Cell 2014; 13:787-96. [PMID: 24931715 PMCID: PMC4172519 DOI: 10.1111/acel.12220] [Citation(s) in RCA: 178] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2014] [Indexed: 12/26/2022] Open
Abstract
Increased expression of SIRT1 extends the lifespan of lower organisms and delays the onset of age-related diseases in mammals. Here, we show that SRT2104, a synthetic small molecule activator of SIRT1, extends both mean and maximal lifespan of mice fed a standard diet. This is accompanied by improvements in health, including enhanced motor coordination, performance, bone mineral density, and insulin sensitivity associated with higher mitochondrial content and decreased inflammation. Short-term SRT2104 treatment preserves bone and muscle mass in an experimental model of atrophy. These results demonstrate it is possible to design a small molecule that can slow aging and delay multiple age-related diseases in mammals, supporting the therapeutic potential of SIRT1 activators in humans.
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Affiliation(s)
- Evi M. Mercken
- Translational Gerontology Branch National Institute on Aging National Institutes of Health Baltimore MD 21224 USA
| | - Sarah J. Mitchell
- Translational Gerontology Branch National Institute on Aging National Institutes of Health Baltimore MD 21224 USA
- Kolling Institute of Medical Research Royal North Shore Hospital St Leonards NSW 2065 Australia
- Sydney Medical School University of Sydney Sydney NSW 2006 Australia
| | - Alejandro Martin‐Montalvo
- Translational Gerontology Branch National Institute on Aging National Institutes of Health Baltimore MD 21224 USA
| | - Robin K. Minor
- Translational Gerontology Branch National Institute on Aging National Institutes of Health Baltimore MD 21224 USA
| | - Maria Almeida
- Division of Endocrinology and Metabolism Center for Osteoporosis and Metabolic Bone Diseases University of Arkansas for Medical Sciences and the Central Arkansas Veterans Health Care System Little Rock AR 72205 USA
| | - Ana P. Gomes
- Glenn Labs for the Biological Mechanisms of Aging Harvard Medical School Boston MA 02115 USA
| | - Morten Scheibye‐Knudsen
- Laboratory of Molecular Gerontology National Institute on Aging National Institutes of Health Baltimore MD 21224 USA
| | - Hector H. Palacios
- Translational Gerontology Branch National Institute on Aging National Institutes of Health Baltimore MD 21224 USA
| | - Jordan J. Licata
- Translational Gerontology Branch National Institute on Aging National Institutes of Health Baltimore MD 21224 USA
| | - Yongqing Zhang
- Gene Expression and Genomics Unit National Institute on Aging National Institutes of Health Baltimore MD 21224 USA
| | - Kevin G. Becker
- Gene Expression and Genomics Unit National Institute on Aging National Institutes of Health Baltimore MD 21224 USA
| | - Husam Khraiwesh
- Departamento de Biología Celular, Fisiología e Inmunología Universidad de Córdoba Campus de Excelencia Internacional Agroalimentario ceiA3 Campus Rabanales Edificio Severo Ochoa 3ª planta Córdoba 14014 Spain
| | - José A. González‐Reyes
- Departamento de Biología Celular, Fisiología e Inmunología Universidad de Córdoba Campus de Excelencia Internacional Agroalimentario ceiA3 Campus Rabanales Edificio Severo Ochoa 3ª planta Córdoba 14014 Spain
| | - José M. Villalba
- Departamento de Biología Celular, Fisiología e Inmunología Universidad de Córdoba Campus de Excelencia Internacional Agroalimentario ceiA3 Campus Rabanales Edificio Severo Ochoa 3ª planta Córdoba 14014 Spain
| | - Joseph A. Baur
- Department Physiology Institute for Diabetes, Obesity, and Metabolism and Perelman School of Medicine University of Pennsylvania PA 19104 USA
| | - Peter Elliott
- Sirtris, a GSK company 200 Technology Square Cambridge MA 02139 USA
| | | | - George P. Vlasuk
- Sirtris, a GSK company 200 Technology Square Cambridge MA 02139 USA
| | - James L. Ellis
- Sirtris, a GSK company 200 Technology Square Cambridge MA 02139 USA
| | - David A. Sinclair
- Glenn Labs for the Biological Mechanisms of Aging Harvard Medical School Boston MA 02115 USA
| | - Michel Bernier
- Translational Gerontology Branch National Institute on Aging National Institutes of Health Baltimore MD 21224 USA
| | - Rafael Cabo
- Translational Gerontology Branch National Institute on Aging National Institutes of Health Baltimore MD 21224 USA
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17
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Naganuma T, Kihara A. Two modes of regulation of the fatty acid elongase ELOVL6 by the 3-ketoacyl-CoA reductase KAR in the fatty acid elongation cycle. PLoS One 2014; 9:e101823. [PMID: 25003994 PMCID: PMC4086937 DOI: 10.1371/journal.pone.0101823] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 06/12/2014] [Indexed: 01/13/2023] Open
Abstract
Fatty acids (FAs) are diverse molecules, and such diversity is important for lipids to exert their functions under several environmental conditions. FA elongation occurs at the endoplasmic reticulum and produces a variety of FA species; the FA elongation cycle consists of four distinct enzyme reactions. For this cycle to be driven efficiently, there must exist coordinated regulation of protein components of the FA elongation machinery. However, such regulation is poorly understood. In the present study, we performed biochemical analyses using the FA elongase ELOVL6 and the 3-ketoacyl-CoA reductase KAR, which catalyze the first and second steps of the FA elongation cycle, respectively. In vitro FA elongation assays using membrane fractions demonstrated that ELOVL6 activity was enhanced ∼10-fold in the presence of NADPH, although ELOVL6 itself did not require NADPH for its catalysis. On the other hand, KAR does use NADPH as a reductant in its enzyme reaction. Activity of purified ELOVL6 was enhanced by ∼3-fold in the presence of KAR. This effect was KAR enzyme activity-independent, since it was observed in the absence of NADPH and in the KAR mutant. However, ELOVL6 enzyme activity was further enhanced in a KAR enzyme activity-dependent manner. Therefore, KAR regulates ELOVL6 via two modes. In the first mode, KAR may induce conformational changes in ELOVL6 to become structure that can undergo catalysis. In the second mode, conversion of 3-ketoacyl-CoA to 3-hydroxyacyl-CoA by KAR may facilitate release of the product from the presumed ELOVL6–KAR complex.
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Affiliation(s)
- Tatsuro Naganuma
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Akio Kihara
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
- * E-mail:
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18
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D'Angelo G, Capasso S, Sticco L, Russo D. Glycosphingolipids: synthesis and functions. FEBS J 2013; 280:6338-53. [PMID: 24165035 DOI: 10.1111/febs.12559] [Citation(s) in RCA: 186] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 09/27/2013] [Accepted: 09/30/2013] [Indexed: 12/21/2022]
Abstract
Glycosphingolipids (GSLs) comprise a heterogeneous group of membrane lipids formed by a ceramide backbone covalently linked to a glycan moiety. Hundreds of different glycans can be linked to tens of different ceramide molecules, giving rise to an astonishing variety of structurally different compounds, each of which has the potential for a specific biological function. GSLs have been suggested to modulate membrane-protein function and to contribute to cell-cell communication. Although GSLs are dispensable for cellular life, they are indeed collectively required for the development of multicellular organisms, and are thus considered to be key molecules in 'cell sociology'. Consequently, the GSL make-up of individual cells is highly dynamic and is strictly linked to the cellular developmental and environmental state. In the present review, we discuss some of the available knowledge, open questions and future perspectives relating to the study of GSL biology.
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Affiliation(s)
- Giovanni D'Angelo
- Institute of Protein Biochemistry, National Research Council, Naples, Italy
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19
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Abstract
The ceramide synthase (CerS) enzymes catalyze the formation of (dihydro) ceramide, and thereby provide critical complexity to all sphingolipids (SLs) with respect to their acyl chain length. This review summarizes the progress in the field of CerS from the time of their discovery more than a decade ago as Longevity assurance (Lass) genes in yeast, until the recent development of CerS-deficient mouse models. Human hereditary CerS disorders are yet to be discovered. However, the recent findings in CerS mutant animals highlight the important physiological role of these enzymes. The fundamental findings with respect to CerS structure, function, localization, and regulation are discussed, as well as CerS roles in maintaining longevity in vivo.
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Affiliation(s)
- Joo-Won Park
- Department of Biochemistry, School of Medicine, Ewha Womans University, Seoul 158-710, South Korea
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20
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Kilpinen L, Tigistu-Sahle F, Oja S, Greco D, Parmar A, Saavalainen P, Nikkilä J, Korhonen M, Lehenkari P, Käkelä R, Laitinen S. Aging bone marrow mesenchymal stromal cells have altered membrane glycerophospholipid composition and functionality. J Lipid Res 2012; 54:622-635. [PMID: 23271708 DOI: 10.1194/jlr.m030650] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Human mesenchymal stem/stromal cells (hMSC) are increasingly used in advanced cellular therapies. The clinical use of hMSCs demands sequential cell expansions. As it is well established that membrane glycerophospholipids (GPL) provide precursors for signaling lipids that modulate cellular functions, we studied the effect of the donor's age and cell doublings on the GPL profile of human bone marrow MSC (hBMSC). The hBMSCs, which were harvested from five young and five old adults, showed clear compositional changes during expansion seen at the level of lipid classes, lipid species, and acyl chains. The ratio of phosphatidylinositol to phosphatidylserine increased toward the late-passage samples. Furthermore, 20:4n-6-containing species of phosphatidylcholine and phosphatidylethanolamine accumulated while the species containing monounsaturated fatty acids (FA) decreased during passaging. Additionally, in the total FA pool of the cells, 20:4n-6 increased, which happened at the expense of n-3 polyunsaturated FAs, especially 22:6n-3. The GPL and FA correlated with the decreased immunosuppressive capacity of hBMSCs during expansion. Our observations were further supported by alterations in the gene expression levels of several enzymes involved in lipid metabolism and immunomodulation. The results show that extensive expansion of hBMSCs harmfully modulates membrane GPLs, affecting lipid signaling and eventually impairing functionality.
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Affiliation(s)
- Lotta Kilpinen
- Advanced Therapies and Product Development, Finnish Red Cross Blood Service, Helsinki, Finland
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21
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Wang Z, Kirkwood JS, Taylor AW, Stevens JF, Leid M, Ganguli-Indra G, Indra AK. Transcription factor Ctip2 controls epidermal lipid metabolism and regulates expression of genes involved in sphingolipid biosynthesis during skin development. J Invest Dermatol 2012; 133:668-676. [PMID: 23096701 PMCID: PMC3556343 DOI: 10.1038/jid.2012.358] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The stratum corneum is composed of protein-enriched corneocytes embedded in an intercellular matrix of nonpolar lipids organized as lamellar layers and give rise to epidermal permeability barrier (EPB). EPB defects play an important role in the pathophysiology of skin diseases such as eczema. The transcriptional control of skin lipid metabolism is poorly understood. We have discovered that mouse lacking a transcription factor COUP-TF interacting protein 2 (Ctip2) exhibit EPB defects including altered keratinocyte terminal differentiation, delayed skin barrier development and interrupted neutral lipid distribution in the epidermis. We adapted herein a targeted lipidomic approach using mass spectrometry, and have determined that Ctip2−/− mice (germline deletion of Ctip2 gene) display altered composition of major epidermal lipids such as ceramides and sphingomyelins compared to wildtype at different stages of skin development. Interestingly, expressions of several genes involved in skin sphingolipid biosynthesis and metabolism were altered in mutant skin. Ctip2 was found to be recruited to the promoter region of a subset of those genes, suggesting their possible direct regulation by Ctip2. Our results confirm an important role of Ctip2 in regulating skin lipid metabolism and indicate that profiling of epidermal sphingolipid could be useful for designing effective strategies to improve barrier dysfunctions.
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Affiliation(s)
- Zhixing Wang
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon, USA
| | - Jay S Kirkwood
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon, USA; Linus Pauling Institute, Corvallis, Oregon, USA
| | | | - Jan F Stevens
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon, USA; Linus Pauling Institute, Corvallis, Oregon, USA
| | - Mark Leid
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon, USA; Molecular Cell Biology Program, Corvallis, Oregon, USA; Environmental Health Science Center, Oregon State University, Corvallis, Oregon, USA
| | - Gitali Ganguli-Indra
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon, USA; Molecular Cell Biology Program, Corvallis, Oregon, USA
| | - Arup K Indra
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon, USA; Molecular Cell Biology Program, Corvallis, Oregon, USA; Environmental Health Science Center, Oregon State University, Corvallis, Oregon, USA; Department of Dermatology, Oregon Health and Science University, Portland, Oregon, USA.
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22
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Nairn AV, Aoki K, dela Rosa M, Porterfield M, Lim JM, Kulik M, Pierce JM, Wells L, Dalton S, Tiemeyer M, Moremen KW. Regulation of glycan structures in murine embryonic stem cells: combined transcript profiling of glycan-related genes and glycan structural analysis. J Biol Chem 2012; 287:37835-56. [PMID: 22988249 DOI: 10.1074/jbc.m112.405233] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The abundance and structural diversity of glycans on glycoproteins and glycolipids are highly regulated and play important roles during vertebrate development. Because of the challenges associated with studying glycan regulation in vertebrate embryos, we have chosen to study mouse embryonic stem (ES) cells as they differentiate into embryoid bodies (EBs) or into extraembryonic endodermal (ExE) cells as a model for cellular differentiation. We profiled N- and O-glycan structures isolated from these cell populations and examined transcripts encoding the corresponding enzymatic machinery for glycan biosynthesis in an effort to probe the mechanisms that drive the regulation of glycan diversity. During differentiation from mouse ES cells to either EBs or ExE cells, general trends were detected. The predominance of high mannose N-glycans in ES cells shifted to an equal abundance of complex and high mannose structures, increased sialylation, and increased α-Gal termination in the differentiated cell populations. Whereas core 1 O-glycan structures predominated in all three cell populations, increased sialylation and increased core diversity characterized the O-glycans of both differentiated cell types. Increased polysialylation was also found in both differentiated cell types. Differences between the two differentiated cell types included greater sialylation of N-glycans in EBs, whereas α-Gal-capped structures were more prevalent in ExE cells. Changes in glycan structures generally, but not uniformly, correlated with alterations in transcript abundance for the corresponding biosynthetic enzymes, suggesting that transcriptional regulation contributes significantly to the regulation of glycan expression. Knowledge of glycan structural diversity and transcript regulation should provide greater understanding of the roles of protein glycosylation in vertebrate development.
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Affiliation(s)
- Alison V Nairn
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602, USA
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23
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Lucki NC, Bandyopadhyay S, Wang E, Merrill AH, Sewer MB. Acid ceramidase (ASAH1) is a global regulator of steroidogenic capacity and adrenocortical gene expression. Mol Endocrinol 2012; 26:228-43. [PMID: 22261821 PMCID: PMC3275158 DOI: 10.1210/me.2011-1150] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 12/14/2011] [Indexed: 11/19/2022] Open
Abstract
In H295R human adrenocortical cells, ACTH rapidly activates ceramide (Cer) and sphingosine (SPH) turnover with a concomitant increase in SPH-1-phosphate secretion. These bioactive lipids modulate adrenocortical steroidogenesis, primarily by acting as second messengers in the protein kinase A/cAMP-dependent pathway. Acid ceramidase (ASAH1) directly regulates the intracellular balance of Cer, SPH, and SPH-1-phosphate by catalyzing the hydrolysis of Cer into SPH. ACTH/cAMP signaling stimulates ASAH1 transcription and activity, supporting a role for this enzyme in glucocorticoid production. Here, the role of ASAH1 in regulating steroidogenic capacity was examined using a tetracycline-inducible ASAH1 short hairpin RNA H295R human adrenocortical stable cell line. We show that ASAH1 suppression increases the transcription of multiple steroidogenic genes, including Cytochrome P450 monooxygenase (CYP)17A1, CYP11B1/2, CYP21A2, steroidogenic acute regulatory protein, hormone-sensitive lipase, 18-kDa translocator protein, and the melanocortin-2 receptor. Induced gene expression positively correlated with enhanced histone H3 acetylation at target promoters. Repression of ASAH1 expression also induced the expression of members of the nuclear receptor nuclear receptor subfamily 4 (NR4A) family while concomitantly suppressing the expression of dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1. ASAH1 knockdown altered the expression of genes involved in sphingolipid metabolism and changed the cellular amounts of distinct sphingolipid species. Finally, ASAH1 silencing increased basal and cAMP-dependent cortisol and dehydroepiandrosterone secretion, establishing ASAH1 as a pivotal regulator of steroidogenic capacity in the human adrenal cortex.
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Affiliation(s)
- Natasha C Lucki
- School of Biology, Georgia Institute of Technology, Atlanta, Georgia 30332-0230, USA
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24
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Bieberich E. It's a lipid's world: bioactive lipid metabolism and signaling in neural stem cell differentiation. Neurochem Res 2012; 37:1208-29. [PMID: 22246226 DOI: 10.1007/s11064-011-0698-5] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Accepted: 12/31/2011] [Indexed: 01/20/2023]
Abstract
Lipids are often considered membrane components whose function is to embed proteins into cell membranes. In the last two decades, studies on brain lipids have unequivocally demonstrated that many lipids have critical cell signaling functions; they are called "bioactive lipids". Pioneering work in Dr. Robert Ledeen's laboratory has shown that two bioactive brain sphingolipids, sphingomyelin and the ganglioside GM1 are major signaling lipids in the nuclear envelope. In addition to derivatives of the sphingolipid ceramide, the bioactive lipids discussed here belong to the classes of terpenoids and steroids, eicosanoids, and lysophospholipids. These lipids act mainly through two mechanisms: (1) direct interaction between the bioactive lipid and a specific protein binding partner such as a lipid receptor, protein kinase or phosphatase, ion exchanger, or other cell signaling protein; and (2) formation of lipid microdomains or rafts that regulate the activity of a group of raft-associated cell signaling proteins. In recent years, a third mechanism has emerged, which invokes lipid second messengers as a regulator for the energy and redox balance of differentiating neural stem cells (NSCs). Interestingly, developmental niches such as the stem cell niche for adult NSC differentiation may also be metabolic compartments that respond to a distinct combination of bioactive lipids. The biological function of these lipids as regulators of NSC differentiation will be reviewed and their application in stem cell therapy discussed.
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Affiliation(s)
- Erhard Bieberich
- Institute of Molecular Medicine and Genetics, Georgia Health Sciences University, 1120 15th Street Room CA4012, Augusta, GA 30912, USA.
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25
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Pontier SM, Schweisguth F. Glycosphingolipids in signaling and development: From liposomes to model organisms. Dev Dyn 2011; 241:92-106. [DOI: 10.1002/dvdy.22766] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/22/2011] [Indexed: 01/05/2023] Open
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26
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Merrill AH. Sphingolipid and glycosphingolipid metabolic pathways in the era of sphingolipidomics. Chem Rev 2011; 111:6387-422. [PMID: 21942574 PMCID: PMC3191729 DOI: 10.1021/cr2002917] [Citation(s) in RCA: 546] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Indexed: 12/15/2022]
Affiliation(s)
- Alfred H Merrill
- School of Biology, and the Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, Georgia 30332-0230, USA.
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27
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Ceramide in stem cell differentiation and embryo development: novel functions of a topological cell-signaling lipid and the concept of ceramide compartments. J Lipids 2010; 2011:610306. [PMID: 21490805 PMCID: PMC3066852 DOI: 10.1155/2011/610306] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Accepted: 11/29/2010] [Indexed: 11/27/2022] Open
Abstract
In the last two decades, the view on the function of ceramide as a sole metabolic precursor for other sphingolipids has completely changed. A plethora of studies has shown that ceramide is an important lipid cell-signaling factor regulating apoptosis in a variety of cell types. With the advent of new stem cell technologies and knockout mice for specific steps in ceramide biosynthesis, this view is about to change again. Recent studies suggest that ceramide is a critical cell-signaling factor for stem cell differentiation and cell polarity, two processes at the core of embryo development. This paper discusses studies on ceramide using in vitro differentiated stem cells, embryo cultures, and knockout mice with the goal of linking specific developmental stages to exciting and novel functions of this lipid. Particular attention is devoted to the concept of ceramide as a topological cell-signaling lipid: a lipid that forms distinct structures (membrane domains and vesicles termed “sphingosome”), which confines ceramide-induced cell signaling pathways to localized and even polarized compartments.
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28
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Abstract
Quantitative real-time polymerase chain reaction (qRT-PCR) is a flexible and scalable method for analyzing transcript abundance that can be used at a single gene or high-throughput (>100 genes) level. Information obtained from this technique can be used as an indicator of potential regulation of glycosylation at the transcript level when combined with glycan structural or protein abundance data. This chapter describes detailed methods to design and perform qRT-PCR analyses and provides examples of information that can be obtained from the technique.
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Affiliation(s)
- Alison V Nairn
- The Complex Carbohydrate Research Center and the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
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