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Yang R, He C, Zhang P, Li Y, Rong S, Chen X, Qi Q, Gao Z, Chi J, Wang L, Cai M, Zhang Y. Plasma sphingolipids, dopaminergic degeneration and clinical progression in idiopathic Parkinson's disease. Parkinsonism Relat Disord 2024; 126:107071. [PMID: 39053098 DOI: 10.1016/j.parkreldis.2024.107071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 07/21/2024] [Accepted: 07/21/2024] [Indexed: 07/27/2024]
Abstract
BACKGROUND Sphingolipid dysregulation in Parkinson's disease (PD) may affect the release and uptake of striatal dopamine. However, the longitudinal relationship between sphingolipids, striatal dopaminergic degeneration, and clinical correlates in idiopathic PD (iPD) remain unclear. OBJECTIVE To investigate the relationship between plasma sphingolipids, striatal dopamine transporter specific binding ratio (DAT-SBR) and clinical symptoms in iPD. METHODS We included 283 iPD patients and 121 healthy controls (HC) from the Parkinson's Progression Markers Initiative (PPMI), utilizing available data on plasma sphingolipids (sphingomyelin [SM] and ceramide [CER]), striatal DAT-SBR and clinical assessments. Linear mixed models and mediation analyses were used to examine the relationship between sphingolipids, DAT-SBR, and clinical progression in iPD. RESULTS Lower baseline SM levels were significantly associated with a faster decline in DAT-SBR in both the caudate (p = 0.015) and putamen (p = 0.002), with the putamen association remaining significant after Bonferroni correction (p = 0.015). No significant association was found for CER. Patients in the lowest quartile of baseline SM showed faster progression in MDS-UPDRS I (p = 0.013) and II (p = 0.011), while those in the lowest quartile of baseline CER showed faster progression in MDS-UPDRS II (p = 0.013) and III (p = 0.033). The progression rate of caudate DAT-SBR partially mediated the relationships between SM and progression in MDS-UPDRS I and II (p < 0.01). CONCLUSION Sphingolipids are associated with worse dopaminergic degeneration and potentially linked to faster progression in iPD, holding the promise for identifying individuals with faster progression in iPD.
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Affiliation(s)
- Rui Yang
- School of Medicine, South China University of Technology, Guangzhou, 510006, China; Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China; Guangzhou Key Laboratory of Diagnosis and Treatment for Neurodegenerative Diseases, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Guangzhou, 510080, China
| | - Chentao He
- Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China
| | - Piao Zhang
- Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China
| | - Yan Li
- Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China
| | - Siming Rong
- Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China
| | - Xi Chen
- Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China
| | - Qi Qi
- Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China
| | - Ziqi Gao
- School of Medicine, South China University of Technology, Guangzhou, 510006, China; Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China
| | - Jieshan Chi
- Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China
| | - Lijuan Wang
- Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China; Guangzhou Key Laboratory of Diagnosis and Treatment for Neurodegenerative Diseases, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Guangzhou, 510080, China
| | - Mengfei Cai
- Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China.
| | - Yuhu Zhang
- School of Medicine, South China University of Technology, Guangzhou, 510006, China; Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, 510080, China; Guangzhou Key Laboratory of Diagnosis and Treatment for Neurodegenerative Diseases, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Guangzhou, 510080, China.
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Singh S, Dransfeld U, Ambaw Y, Lopez-Scarim J, Farese RV, Walther TC. PLD3 and PLD4 synthesize S,S-BMP, a key phospholipid enabling lipid degradation in lysosomes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.21.586175. [PMID: 38562702 PMCID: PMC10983895 DOI: 10.1101/2024.03.21.586175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Bis(monoacylglycero)phosphate (BMP) is an abundant lysosomal phospholipid required for degradation of lipids, in particular gangliosides. Alterations in BMP levels are associated with neurodegenerative diseases. Unlike typical glycerophospholipids, lysosomal BMP has two chiral glycerol carbons in the S (rather than the R) stereo-conformation, protecting it from lysosomal degradation. How this unusual and yet crucial S,S-stereochemistry is achieved is unknown. Here we report that phospholipases D3 and D4 (PLD3 and PLD4) synthesize lysosomal S,S-BMP, with either enzyme catalyzing the critical glycerol stereo-inversion reaction in vitro. Deletion of PLD3 or PLD4 markedly reduced BMP levels in cells or in murine tissues where either enzyme is highly expressed (brain for PLD3; spleen for PLD4), leading to gangliosidosis and lysosomal abnormalities. PLD3 mutants associated with neurodegenerative diseases, including Alzheimer's disease risk, diminished PLD3 catalytic activity. We conclude that PLD3/4 enzymes synthesize lysosomal S,S-BMP, a crucial lipid for maintaining brain health.
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Affiliation(s)
- Shubham Singh
- Cell Biology Program, Sloan Kettering Institute, MSKCC, New York, NY, USA
| | - Ulrich Dransfeld
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Yohannes Ambaw
- Cell Biology Program, Sloan Kettering Institute, MSKCC, New York, NY, USA
| | - Joshua Lopez-Scarim
- Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD Program, New York, NY, USA
| | - Robert V. Farese
- Cell Biology Program, Sloan Kettering Institute, MSKCC, New York, NY, USA
| | - Tobias C. Walther
- Cell Biology Program, Sloan Kettering Institute, MSKCC, New York, NY, USA
- Howard Hughes Medical Institute, New York, NY, USA
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3
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Wang X, Li H, Sheng Y, He B, Liu Z, Li W, Yu S, Wang J, Zhang Y, Chen J, Qin L, Meng X. The function of sphingolipids in different pathogenesis of Alzheimer's disease: A comprehensive review. Biomed Pharmacother 2024; 171:116071. [PMID: 38183741 DOI: 10.1016/j.biopha.2023.116071] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 12/11/2023] [Accepted: 12/21/2023] [Indexed: 01/08/2024] Open
Abstract
Sphingolipids (SPLs) represent a highly diverse and structurally complex lipid class. The discussion of SPL metabolism-related issues is of importance in understanding the neuropathological progression of Alzheimer's disease (AD). AD is characterized by the accumulation of extracellular deposits of the amyloid β-peptide (Aβ) and intraneuronal aggregates of the microtubule-associated protein tau. Critical roles of Aβ oligomer deposited and ganglioside GM1 could be formed as "seed" from insoluble GAβ polymer in initiating the pathogenic process, while tau might also mediate SPLs and their toxicity. The interaction between ceramide and α-Synuclein (α-Syn) accelerates the aggregation of ferroptosis and exacerbates the pathogenesis of AD. For instance, reducing the levels of SPLs can mitigate α-Syn accumulation and inhibit AD progression. Meanwhile, loss of SPLs may inhibit the expression of APOE4 and confer protection against AD, while the loss of APOE4 expression also disrupts SPLs homeostasis. Moreover, the heightened activation of sphingomyelinase promotes the ferroptosis signaling pathway, leading to exacerbated AD symptoms. Ferroptosis plays a vital role in the pathological progression of AD by influencing Aβ, tau, APOE, and α-Syn. Conversely, the development of AD also exacerbates the manifestation of ferroptosis and SPLs. We are compiling the emerging techniques (Derivatization and IM-MS) of sphingolipidomics, to overcome the challenges of AD diagnosis and treatment. In this review, we examined the intricate neuro-mechanistic interactions between SPLs and Aβ, tau, α-Syn, APOE, and ferroptosis, mediating the onset of AD. Furthermore, our findings highlight the potential of targeting SPLs as underexplored avenue for devising innovative therapeutic strategies against AD.
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Affiliation(s)
- Xinyi Wang
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou 310053, Zhejiang Province, PR China
| | - Huaqiang Li
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou 310053, Zhejiang Province, PR China
| | - Yunjie Sheng
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou 310053, Zhejiang Province, PR China
| | - Bingqian He
- Academy of Chinese Medical Science, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou 310053, Zhejiang Province, PR China
| | - Zeying Liu
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou 310053, Zhejiang Province, PR China
| | - Wanli Li
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou 310053, Zhejiang Province, PR China
| | - Shujie Yu
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou 310053, Zhejiang Province, PR China
| | - Jiajing Wang
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou 310053, Zhejiang Province, PR China
| | - Yixin Zhang
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou 310053, Zhejiang Province, PR China
| | - Jianyu Chen
- Fujian University of Traditional Chinese Medicine, School of Pharmacy, Fuzhou, Fujian 350122, PR China.
| | - Luping Qin
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou 310053, Zhejiang Province, PR China.
| | - Xiongyu Meng
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou 310053, Zhejiang Province, PR China.
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Piña F, Yan B, Hu J, Niwa M. Reticulons bind sphingolipids to activate the endoplasmic reticulum cell cycle checkpoint, the ER surveillance pathway. Cell Rep 2023; 42:113403. [PMID: 37979174 DOI: 10.1016/j.celrep.2023.113403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 12/09/2022] [Accepted: 10/23/2023] [Indexed: 11/20/2023] Open
Abstract
The inheritance of a functional endoplasmic reticulum (ER) is ensured by the ER stress surveillance (ERSU) pathway. Here, we made the unexpected discovery that reticulon 1 (Rtn1) and Yop1, well-known ER-curvature-generating proteins, each possess two sphingolipid-binding motifs within their transmembrane domains and that these motifs recognize the ER-stress-induced sphingolipid phytosphingosine (PHS), resulting in an ER inheritance block. Upon binding PHS, Rtn1/Yop1 accumulate on the ER tubule, poised to enter the emerging daughter cell, and cause its misdirection to the bud scars (i.e., previous cell division sites). Amino acid changes in the conserved PHS-binding motifs preclude Rtn1 or Yop1 from binding PHS and diminish their enrichment on the tubular ER, ultimately preventing the ER-stress-induced inheritance block. Conservation of these sphingolipid-binding motifs in human reticulons suggests that sphingolipid binding to Rtn1 and Yop1 represents an evolutionarily conserved mechanism that enables cells to respond to ER stress.
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Affiliation(s)
- Francisco Piña
- Division of Biological Sciences, Molecular Biology Section, University of California, San Diego, NSB#1, Rm. 5328, 9500 Gilman Drive, San Diego, CA 92093-0377, USA
| | - Bing Yan
- Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Rm. 6210, Chaoyang District, Beijing 100101, China
| | - Junjie Hu
- Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Rm. 6210, Chaoyang District, Beijing 100101, China
| | - Maho Niwa
- Division of Biological Sciences, Molecular Biology Section, University of California, San Diego, NSB#1, Rm. 5328, 9500 Gilman Drive, San Diego, CA 92093-0377, USA.
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5
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Wei J, Wong LC, Boland S. Lipids as Emerging Biomarkers in Neurodegenerative Diseases. Int J Mol Sci 2023; 25:131. [PMID: 38203300 PMCID: PMC10778656 DOI: 10.3390/ijms25010131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 12/11/2023] [Accepted: 12/13/2023] [Indexed: 01/12/2024] Open
Abstract
Biomarkers are molecules that can be used to observe changes in an individual's biochemical or medical status and provide information to aid diagnosis or treatment decisions. Dysregulation in lipid metabolism in the brain is a major risk factor for many neurodegenerative disorders, including frontotemporal dementia, Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. Thus, there is a growing interest in using lipids as biomarkers in neurodegenerative diseases, with the anionic phospholipid bis(monoacylglycerol)phosphate and (glyco-)sphingolipids being the most promising lipid classes thus far. In this review, we provide a general overview of lipid biology, provide examples of abnormal lysosomal lipid metabolism in neurodegenerative diseases, and discuss how these insights might offer novel and promising opportunities in biomarker development and therapeutic discovery. Finally, we discuss the challenges and opportunities of lipid biomarkers and biomarker panels in diagnosis, prognosis, and/or treatment response in the clinic.
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6
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Zhu JY, Ni XS, Han XY, Liu S, Ji YK, Yao J, Yan B. Metabolomic profiling of a neurodegenerative retina following optic nerve transection. Mol Med Rep 2023; 28:178. [PMID: 37539744 PMCID: PMC10433715 DOI: 10.3892/mmr.2023.13065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 07/19/2023] [Indexed: 08/05/2023] Open
Abstract
The degeneration of retinal ganglion cells (RGCs) often causes irreversible vision impairment. Prevention of RGC degeneration can prevent or delay the deterioration of visual function. The present study aimed to investigate retinal metabolic profiles following optic nerve transection (ONT) injury and identify the potential metabolic targets for the prevention of RGC degeneration. Retinal samples were dissected from ONT group and non‑ONT group. The untargeted metabolomics were carried out using liquid chromatography‑tandem mass spectrometry. The involved pathways and biomarkers were analyzed using Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and MetaboAnalyst 5.0. In the ONT group, 689 disparate metabolites were detected, including lipids and lipid‑like molecules. A total of 122 metabolites were successfully annotated and enriched in 50 KEGG pathways. Among them, 'sphingolipid metabolism' and 'primary bile acid biosynthesis' were identified involved in RGC degeneration. A total of five metabolites were selected as the candidate biomarkers for detecting RGC degeneration with an AUC value of 1. The present study revealed that lipid‑related metabolism was involved in the pathogenesis of retinal neurodegeneration. Taurine, taurochenodesoxycholic acid, taurocholic acid (TCA), sphingosine, and galabiosylceramide are shown as the promising biomarkers for the diagnosis of RGC degeneration.
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Affiliation(s)
- Jun-Ya Zhu
- Department of Ophthalmology and Optometry, The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
- Eye Institute and Department of Ophthalmology, Eye and Ear, Nose and Throat Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200030, P.R. China
| | - Xi-Sen Ni
- Department of Ophthalmology and Optometry, The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
- Department of Ophthalmology and Optometry, The Affiliated Eye Hospital, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Xiao-Yan Han
- Eye Institute and Department of Ophthalmology, Eye and Ear, Nose and Throat Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200030, P.R. China
| | - Sha Liu
- Department of Ophthalmology and Optometry, The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
- Department of Ophthalmology and Optometry, The Affiliated Eye Hospital, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Yu-Ke Ji
- Department of Ophthalmology and Optometry, The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
- Department of Ophthalmology and Optometry, The Affiliated Eye Hospital, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Jin Yao
- Department of Ophthalmology and Optometry, The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
- Department of Ophthalmology and Optometry, The Affiliated Eye Hospital, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Biao Yan
- Eye Institute and Department of Ophthalmology, Eye and Ear, Nose and Throat Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200030, P.R. China
- National Health Commission Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai 200030, P.R. China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai 200030, P.R. China
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Shi M, Tang C, Wu JX, Ji BW, Gong BM, Wu XH, Wang X. Mass Spectrometry Detects Sphingolipid Metabolites for Discovery of New Strategy for Cancer Therapy from the Aspect of Programmed Cell Death. Metabolites 2023; 13:867. [PMID: 37512574 PMCID: PMC10384871 DOI: 10.3390/metabo13070867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/14/2023] [Accepted: 07/17/2023] [Indexed: 07/30/2023] Open
Abstract
Sphingolipids, a type of bioactive lipid, play crucial roles within cells, serving as integral components of membranes and exhibiting strong signaling properties that have potential therapeutic implications in anti-cancer treatments. However, due to the diverse group of lipids and intricate mechanisms, sphingolipids still face challenges in enhancing the efficacy of different therapy approaches. In recent decades, mass spectrometry has made significant advancements in uncovering sphingolipid biomarkers and elucidating their impact on cancer development, progression, and resistance. Primary sphingolipids, such as ceramide and sphingosine-1-phosphate, exhibit contrasting roles in regulating cancer cell death and survival. The evasion of cell death is a characteristic hallmark of cancer cells, leading to treatment failure and a poor prognosis. The escape initiates with long-established apoptosis and extends to other programmed cell death (PCD) forms when patients experience chemotherapy, radiotherapy, and/or immunotherapy. Gradually, supportive evidence has uncovered the fundamental molecular mechanisms underlying various forms of PCD leading to the development of innovative molecular, genetic, and pharmacological tools that specifically target sphingolipid signaling nodes. In this study, we provide a comprehensive overview of the sphingolipid biomarkers revealed through mass spectrometry in recent decades, as well as an in-depth analysis of the six main forms of PCD (apoptosis, autophagy, pyroptosis, necroptosis, ferroptosis, and cuproptosis) in aspects of tumorigenesis, metastasis, and tumor response to treatments. We review the corresponding small-molecule compounds associated with these processes and their potential implications in cancer therapy.
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Affiliation(s)
- Ming Shi
- State Key Laboratory of Genetic Engineering and National Center for International Research of Development and Disease, Collaborative Innovation Center of Genetics and Development, Institute of Developmental Biology and Molecular Medicine, School of Life Sciences, Fudan University, Shanghai 200438, China
- Dongguan Key Laboratory of Medical Bioactive Molecular Developmental and Translational Research, Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, Guangdong Medical University, Dongguan 523808, China
| | - Chao Tang
- National Clinical Research Center for Child Health, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Jia-Xing Wu
- SINO-SWISS Institute of Advanced Technology, School of Microelectronics, Shanghai University, Shanghai 200444, China
| | - Bao-Wei Ji
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai 200032, China
| | - Bao-Ming Gong
- State Key Laboratory of Genetic Engineering and National Center for International Research of Development and Disease, Collaborative Innovation Center of Genetics and Development, Institute of Developmental Biology and Molecular Medicine, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xiao-Hui Wu
- State Key Laboratory of Genetic Engineering and National Center for International Research of Development and Disease, Collaborative Innovation Center of Genetics and Development, Institute of Developmental Biology and Molecular Medicine, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xue Wang
- State Key Laboratory of Genetic Engineering and National Center for International Research of Development and Disease, Collaborative Innovation Center of Genetics and Development, Institute of Developmental Biology and Molecular Medicine, School of Life Sciences, Fudan University, Shanghai 200438, China
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Hepowit NL, Moon B, Ebert AC, Dickson RC, MacGurn JA. Art2 mediates selective endocytosis of methionine transporters during adaptation to sphingolipid depletion. J Cell Sci 2023; 136:jcs260675. [PMID: 37337792 PMCID: PMC10399987 DOI: 10.1242/jcs.260675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 06/01/2023] [Indexed: 06/21/2023] Open
Abstract
Accumulating evidence in several model organisms indicates that reduced sphingolipid biosynthesis promotes longevity, although underlying mechanisms remain unclear. In yeast, sphingolipid depletion induces a state resembling amino acid restriction, which we hypothesized might be due to altered stability of amino acid transporters at the plasma membrane. To test this, we measured surface abundance for a diverse panel of membrane proteins in the presence of myriocin, a sphingolipid biosynthesis inhibitor, in Saccharomyces cerevisiae. Unexpectedly, we found that surface levels of most proteins examined were either unaffected or increased during myriocin treatment, consistent with an observed decrease in bulk endocytosis. In contrast, sphingolipid depletion triggered selective endocytosis of the methionine transporter Mup1. Unlike methionine-induced Mup1 endocytosis, myriocin triggered Mup1 endocytosis that required the Rsp5 adaptor Art2, C-terminal lysine residues of Mup1 and the formation of K63-linked ubiquitin polymers. These findings reveal cellular adaptation to sphingolipid depletion by ubiquitin-mediated remodeling of nutrient transporter composition at the cell surface.
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Affiliation(s)
- Nathaniel L. Hepowit
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Bradley Moon
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Adam C. Ebert
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Robert C. Dickson
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Jason A. MacGurn
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
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Lima TI, Laurila PP, Wohlwend M, Morel JD, Goeminne LJE, Li H, Romani M, Li X, Oh CM, Park D, Rodríguez-López S, Ivanisevic J, Gallart-Ayala H, Crisol B, Delort F, Batonnet-Pichon S, Silveira LR, Sankabattula Pavani Veera Venkata L, Padala AK, Jain S, Auwerx J. Inhibiting de novo ceramide synthesis restores mitochondrial and protein homeostasis in muscle aging. Sci Transl Med 2023; 15:eade6509. [PMID: 37196064 DOI: 10.1126/scitranslmed.ade6509] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 04/28/2023] [Indexed: 05/19/2023]
Abstract
Disruption of mitochondrial function and protein homeostasis plays a central role in aging. However, how these processes interact and what governs their failure in aging remain poorly understood. Here, we showed that ceramide biosynthesis controls the decline in mitochondrial and protein homeostasis during muscle aging. Analysis of transcriptome datasets derived from muscle biopsies obtained from both aged individuals and patients with a diverse range of muscle disorders revealed that changes in ceramide biosynthesis, as well as disturbances in mitochondrial and protein homeostasis pathways, are prevalent features in these conditions. By performing targeted lipidomics analyses, we found that ceramides accumulated in skeletal muscle with increasing age across Caenorhabditis elegans, mice, and humans. Inhibition of serine palmitoyltransferase (SPT), the rate-limiting enzyme of the ceramide de novo synthesis, by gene silencing or by treatment with myriocin restored proteostasis and mitochondrial function in human myoblasts, in C. elegans, and in the skeletal muscles of mice during aging. Restoration of these age-related processes improved health and life span in the nematode and muscle health and fitness in mice. Collectively, our data implicate pharmacological and genetic suppression of ceramide biosynthesis as potential therapeutic approaches to delay muscle aging and to manage related proteinopathies via mitochondrial and proteostasis remodeling.
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Affiliation(s)
- Tanes I Lima
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Pirkka-Pekka Laurila
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Martin Wohlwend
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Jean David Morel
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Ludger J E Goeminne
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Hao Li
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Mario Romani
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Xiaoxu Li
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Chang-Myung Oh
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea
| | - Dohyun Park
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Sandra Rodríguez-López
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Julijana Ivanisevic
- Metabolomics Platform, Faculty of Biology and Medicine, University of Lausanne (UNIL), Lausanne 1005, Switzerland
| | - Hector Gallart-Ayala
- Metabolomics Platform, Faculty of Biology and Medicine, University of Lausanne (UNIL), Lausanne 1005, Switzerland
| | - Barbara Crisol
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Florence Delort
- Laboratoire Biologie Fonctionnelle et Adaptative, UMR 8251, CNRS and Université Paris Cité, Paris 8251, France
| | - Sabrina Batonnet-Pichon
- Laboratoire Biologie Fonctionnelle et Adaptative, UMR 8251, CNRS and Université Paris Cité, Paris 8251, France
| | - Leonardo R Silveira
- Obesity and Comorbidities Research Center, University of Campinas, Campinas 13083-864, Brazil
| | | | - Anil K Padala
- Intonation Research Laboratories, Hyderabad 500076, India
| | - Suresh Jain
- Intonation Research Laboratories, Hyderabad 500076, India
| | - Johan Auwerx
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
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10
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Callegari K, Dash S, Uchida H, Shingai Y, Liu C, Khodarkovskaya A, Lee Y, Ito A, Lopez A, Zhang T, Xiang J, Kluk MJ, Sanchez T. Molecular profiling of the stroke-induced alterations in the cerebral microvasculature reveals promising therapeutic candidates. Proc Natl Acad Sci U S A 2023; 120:e2205786120. [PMID: 37058487 PMCID: PMC10120001 DOI: 10.1073/pnas.2205786120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 02/08/2023] [Indexed: 05/11/2023] Open
Abstract
Stroke-induced cerebral microvascular dysfunction contributes to aggravation of neuronal injury and compromises the efficacy of current reperfusion therapies. Understanding the molecular alterations in cerebral microvessels in stroke will provide original opportunities for scientific investigation of novel therapeutic strategies. Toward this goal, using a recently optimized method which minimizes cell activation and preserves endothelial cell interactions and RNA integrity, we conducted a genome-wide transcriptomic analysis of cerebral microvessels in a mouse model of stroke and compared these transcriptomic alterations with the ones observed in human, nonfatal, brain stroke lesions. Results from these unbiased comparative analyses have revealed the common alterations in mouse stroke microvessels and human stroke lesions and identified shared molecular features associated with vascular disease (e.g., Serpine1/Plasminogen Activator Inhibitor-1, Hemoxygenase-1), endothelial activation (e.g., Angiopoietin-2), and alterations in sphingolipid metabolism and signaling (e.g., Sphigosine-1-Phosphate Receptor 2). Sphingolipid profiling of mouse cerebral microvessels validated the transcript data and revealed the enrichment of sphingomyelin and sphingoid species in the cerebral microvasculature compared to brain and the stroke-induced increase in ceramide species. In summary, our study has identified novel molecular alterations in several microvessel-enriched, translationally relevant, and druggable targets, which are potent modulators of endothelial function. Our comparative analyses have revealed the presence of molecular features associated with cerebral microvascular dysfunction in human chronic stroke lesions. The results shared here provide a detailed resource for therapeutic discovery of candidates for neurovascular protection in stroke and potentially, other pathologies exhibiting cerebral microvascular dysfunction.
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Affiliation(s)
- Keri Callegari
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY10065
| | - Sabyasachi Dash
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY10065
| | - Hiroki Uchida
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY10065
| | - Yuto Shingai
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY10065
| | - Catherine Liu
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY10065
| | - Anne Khodarkovskaya
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY10065
| | - Yunkyoung Lee
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY10065
| | - Akira Ito
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY10065
| | - Amanda Lopez
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY10065
| | - Tuo Zhang
- Genomics Resources Core Facility, Weill Cornell Medicine, New York, NY10065
| | - Jenny Xiang
- Genomics Resources Core Facility, Weill Cornell Medicine, New York, NY10065
| | - Michael J. Kluk
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY10065
| | - Teresa Sanchez
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY10065
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY10065
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11
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Lee RMQ, Koh TW. Genetic modifiers of synucleinopathies-lessons from experimental models. OXFORD OPEN NEUROSCIENCE 2023; 2:kvad001. [PMID: 38596238 PMCID: PMC10913850 DOI: 10.1093/oons/kvad001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/04/2023] [Accepted: 03/07/2023] [Indexed: 04/11/2024]
Abstract
α-Synuclein is a pleiotropic protein underlying a group of progressive neurodegenerative diseases, including Parkinson's disease and dementia with Lewy bodies. Together, these are known as synucleinopathies. Like all neurological diseases, understanding of disease mechanisms is hampered by the lack of access to biopsy tissues, precluding a real-time view of disease progression in the human body. This has driven researchers to devise various experimental models ranging from yeast to flies to human brain organoids, aiming to recapitulate aspects of synucleinopathies. Studies of these models have uncovered numerous genetic modifiers of α-synuclein, most of which are evolutionarily conserved. This review discusses what we have learned about disease mechanisms from these modifiers, and ways in which the study of modifiers have supported ongoing efforts to engineer disease-modifying interventions for synucleinopathies.
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Affiliation(s)
- Rachel Min Qi Lee
- Temasek Life Sciences Laboratory, 1 Research Link, Singapore, 117604, Singapore
| | - Tong-Wey Koh
- Temasek Life Sciences Laboratory, 1 Research Link, Singapore, 117604, Singapore
- Department of Biological Sciences, National University of Singapore, Block S3 #05-01, 16 Science Drive 4, Singapore, 117558, Singapore
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12
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Hepowit NL, Blalock E, Lee S, Bretland KM, MacGurn JA, Dickson RC. Reduced sphingolipid biosynthesis modulates proteostasis networks to enhance longevity. Aging (Albany NY) 2023; 15:472-491. [PMID: 36640272 PMCID: PMC9925692 DOI: 10.18632/aging.204485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 12/29/2022] [Indexed: 01/15/2023]
Abstract
As the elderly population increases, chronic, age-associated diseases are challenging healthcare systems around the world. Nutrient limitation is well known to slow the aging process and improve health. Regrettably, practicing nutrient restriction to improve health is unachievable for most people. Alternatively, pharmacological strategies are being pursued including myriocin which increases lifespan in budding yeast. Myriocin impairs sphingolipid synthesis, resulting in lowered amino acid pools which promote entry into a quiescent, long-lived state. Here we present transcriptomic data during the first 6 hours of drug treatment that improves our mechanistic understanding of the cellular response to myriocin and reveals a new role for ubiquitin in longevity. Previously we found that the methionine transporter Mup1 traffics to the plasma membrane normally in myriocin-treated cells but is not active and undergoes endocytic clearance. We now show that UBI4, a gene encoding stressed-induced ubiquitin, is vital for myriocin-enhanced lifespan. Furthermore, we show that Mup1 fused to a deubiquitinase domain impairs myriocin-enhanced longevity. Broader effects of myriocin treatment on ubiquitination are indicated by our finding of a significant increase in K63-linked ubiquitin polymers following myriocin treatment. Although proteostasis is broadly accepted as a pillar of aging, our finding that ubiquitination of an amino acid transporter promotes longevity in myriocin-treated cells is novel. Addressing the role of ubiquitination/deubiquitination in longevity has the potential to reveal new strategies and targets for promoting healthy aging.
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Affiliation(s)
- Nathaniel L. Hepowit
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Eric Blalock
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY 40536, USA
| | - Sangderk Lee
- College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA
| | - Kimberly M. Bretland
- Department of Pharmacology and Nutritional Science, University of Kentucky, Lexington, KY 40536, USA
| | - Jason A. MacGurn
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Robert C. Dickson
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
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13
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Pan X, Dutta D, Lu S, Bellen HJ. Sphingolipids in neurodegenerative diseases. Front Neurosci 2023; 17:1137893. [PMID: 36875645 PMCID: PMC9978793 DOI: 10.3389/fnins.2023.1137893] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 01/27/2023] [Indexed: 02/18/2023] Open
Abstract
Neurodegenerative Diseases (NDDs) are a group of disorders that cause progressive deficits of neuronal function. Recent evidence argues that sphingolipid metabolism is affected in a surprisingly broad set of NDDs. These include some lysosomal storage diseases (LSDs), hereditary sensory and autonomous neuropathy (HSAN), hereditary spastic paraplegia (HSP), infantile neuroaxonal dystrophy (INAD), Friedreich's ataxia (FRDA), as well as some forms of amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD). Many of these diseases have been modeled in Drosophila melanogaster and are associated with elevated levels of ceramides. Similar changes have also been reported in vertebrate cells and mouse models. Here, we summarize studies using fly models and/or patient samples which demonstrate the nature of the defects in sphingolipid metabolism, the organelles that are implicated, the cell types that are initially affected, and potential therapeutics for these diseases.
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Affiliation(s)
- Xueyang Pan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States
| | - Debdeep Dutta
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States
| | - Shenzhao Lu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States
| | - Hugo J Bellen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States
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14
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Khakurel A, Kudlyk T, Pokrovskaya I, D’Souza Z, Lupashin VV. GARP dysfunction results in COPI displacement, depletion of Golgi v-SNAREs and calcium homeostasis proteins. Front Cell Dev Biol 2022; 10:1066504. [PMID: 36578782 PMCID: PMC9791199 DOI: 10.3389/fcell.2022.1066504] [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: 10/10/2022] [Accepted: 11/30/2022] [Indexed: 12/14/2022] Open
Abstract
Golgi-associated retrograde protein (GARP) is an evolutionary conserved heterotetrameric protein complex that tethers endosome-derived vesicles and is vital for Golgi glycosylation. Microscopy and proteomic approaches were employed to investigate defects in Golgi physiology in RPE1 cells depleted for the GARP complex. Both cis and trans-Golgi compartments were significantly enlarged in GARP-knock-out (KO) cells. Proteomic analysis of Golgi-enriched membranes revealed significant depletion of a subset of Golgi residents, including Ca2+ binding proteins, enzymes, and SNAREs. Validation of proteomics studies revealed that SDF4 and ATP2C1, related to Golgi calcium homeostasis, as well as intra-Golgi v-SNAREs GOSR1 and BET1L, were significantly depleted in GARP-KO cells. Finding that GARP-KO is more deleterious to Golgi physiology than deletion of GARP-sensitive v-SNAREs, prompted a detailed investigation of COPI trafficking machinery. We discovered that in GARP-KO cells COPI is significantly displaced from the Golgi and partially relocalized to the ER-Golgi intermediate compartment (ERGIC). Moreover, COPI accessory proteins GOLPH3, ARFGAP1, GBF1, and BIG1 are also relocated to off-Golgi compartments. We propose that the dysregulation of COPI machinery, along with the depletion of Golgi v-SNAREs and alteration of Golgi Ca2+ homeostasis, are the major driving factors for the depletion of Golgi resident proteins, structural alterations, and glycosylation defects in GARP deficient cells.
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15
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Vti1a/b support distinct aspects of TGN and cis-/medial Golgi organization. Sci Rep 2022; 12:20870. [PMID: 36460703 PMCID: PMC9718741 DOI: 10.1038/s41598-022-25331-x] [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: 07/15/2022] [Accepted: 11/28/2022] [Indexed: 12/03/2022] Open
Abstract
Retrograde trafficking towards the trans-Golgi network (TGN) is important for dense core vesicle (DCV) biogenesis. Here, we used Vti1a/b deficient neurons to study the impact of disturbed retrograde trafficking on Golgi organization and cargo sorting. In Vti1a/b deficient neurons, staining intensity of cis-/medial Golgi proteins (e.g., GM130 and giantin) was increased, while the intensity of two recycling TGN proteins, TGN38 and TMEM87A, was decreased and the TGN-resident protein Golgin97 was normal. Levels and localization of DCV cargo markers, LAMP1 and KDEL were also altered. This phenotype was not caused by reduced Golgi size or absence of a TGN compartment. The phenotype was partially phenocopied by disturbing sphingolipid homeostasis, but was not rescued by overexpression of sphingomyelin synthases or the sphingolipid synthesis inhibitor myriocin. We conclude that Vti1a/b are important for distinct aspects of TGN and cis-/medial Golgi organization. Our data underline the importance of retrograde trafficking for Golgi organization, DCV cargo sorting and the distribution of proteins of the regulated secretory pathway.
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16
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Bonet-Ponce L, Cookson MR. LRRK2 recruitment, activity, and function in organelles. FEBS J 2022; 289:6871-6890. [PMID: 34196120 PMCID: PMC8744135 DOI: 10.1111/febs.16099] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 05/13/2021] [Accepted: 06/30/2021] [Indexed: 01/13/2023]
Abstract
Protein coding mutations in leucine-rich repeat kinase 2 (LRRK2) cause familial Parkinson's disease (PD), and noncoding variations around the gene increase the risk of developing sporadic PD. It is generally accepted that pathogenic LRRK2 mutations increase LRRK2 kinase activity, resulting in a toxic hyperactive protein that is inferred to lead to the PD phenotype. LRRK2 has long been linked to different membrane trafficking events, but the specific role of LRRK2 in these events has been difficult to resolve. Recently, several papers have reported the activation and translocation of LRRK2 to cellular organelles under specific conditions, which suggests that LRRK2 may influence intracellular membrane trafficking. Here, we review what is known about the role of LRRK2 at various organelle compartments.
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Affiliation(s)
| | - Mark R. Cookson
- Correspondence: Mark R. Cookson, Ph.D., Cell Biology and Gene Expression Section, Laboratory of Neurogenetics, National Institute on Aging, NIH, 35 Convent Drive, Room 1A–116, Bethesda, MD, 20892–3707, USA. Phone: 301–451–3870,
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17
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McCluskey G, Donaghy C, Morrison KE, McConville J, Duddy W, Duguez S. The Role of Sphingomyelin and Ceramide in Motor Neuron Diseases. J Pers Med 2022; 12:jpm12091418. [PMID: 36143200 PMCID: PMC9501626 DOI: 10.3390/jpm12091418] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 08/26/2022] [Accepted: 08/27/2022] [Indexed: 11/16/2022] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS), Spinal Bulbar Muscular Atrophy (SBMA), and Spinal Muscular Atrophy (SMA) are motor neuron diseases (MNDs) characterised by progressive motor neuron degeneration, weakness and muscular atrophy. Lipid dysregulation is well recognised in each of these conditions and occurs prior to neurodegeneration. Several lipid markers have been shown to predict prognosis in ALS. Sphingolipids are complex lipids enriched in the central nervous system and are integral to key cellular functions including membrane stability and signalling pathways, as well as being mediators of neuroinflammation and neurodegeneration. This review highlights the metabolism of sphingomyelin (SM), the most abundant sphingolipid, and of its metabolite ceramide, and its role in the pathophysiology of neurodegeneration, focusing on MNDs. We also review published lipidomic studies in MNDs. In the 13 studies of patients with ALS, 12 demonstrated upregulation of multiple SM species and 6 demonstrated upregulation of ceramides. SM species also correlated with markers of clinical progression in five of six studies. These data highlight the potential use of SM and ceramide as biomarkers in ALS. Finally, we review potential therapeutic strategies for targeting sphingolipid metabolism in neurodegeneration.
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Affiliation(s)
- Gavin McCluskey
- Personalised Medicine Center, School of Medicine, Ulster University, Derry BT47 6SB, UK
- Department of Neurology, Altnagelvin Hospital, Derry, BT47 6SB, UK
- Department of Neurology, Royal Victoria Hospital, Belfast BT12 6BA, UK
| | - Colette Donaghy
- Department of Neurology, Altnagelvin Hospital, Derry, BT47 6SB, UK
| | - Karen E. Morrison
- Department of Neurology, Royal Victoria Hospital, Belfast BT12 6BA, UK
- Faculty of Medicine, Health & Life Sciences, Queen’s University, Belfast BT9 6AG, UK
| | - John McConville
- Department of Neurology, Royal Victoria Hospital, Belfast BT12 6BA, UK
- Department of Neurology, Ulster Hospital, Dundonald, Belfast BT16 1RH, UK
| | - William Duddy
- Personalised Medicine Center, School of Medicine, Ulster University, Derry BT47 6SB, UK
| | - Stephanie Duguez
- Personalised Medicine Center, School of Medicine, Ulster University, Derry BT47 6SB, UK
- Correspondence:
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18
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Ceramide and Sphingosine-1-Phosphate in Neurodegenerative Disorders and Their Potential Involvement in Therapy. Int J Mol Sci 2022; 23:ijms23147806. [PMID: 35887154 PMCID: PMC9324343 DOI: 10.3390/ijms23147806] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/08/2022] [Accepted: 07/11/2022] [Indexed: 02/04/2023] Open
Abstract
Neurodegenerative disorders (ND) are progressive diseases of the nervous system, often without resolutive therapy. They are characterized by a progressive impairment and loss of specific brain regions and neuronal populations. Cellular and animal model studies have identified several molecular mechanisms that play an important role in the pathogenesis of ND. Among them are alterations of lipids, in particular sphingolipids, that play a crucial role in neurodegeneration. Overall, during ND, ceramide-dependent pro-apoptotic signalling is promoted, whereas levels of the neuroprotective spingosine-1-phosphate are reduced. Moreover, ND are characterized by alterations of the metabolism of complex sphingolipids. The finding that altered sphingolipid metabolism has a role in ND suggests that its modulation might provide a useful strategy to identify targets for possible therapies. In this review, based on the current literature, we will discuss how bioactive sphingolipids (spingosine-1-phosphate and ceramide) are involved in some ND (Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis) and their possible involvement in therapies.
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19
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Liu Y, He L, Liu B, Ying Y, Xu J, Yu M, Dang J, Liu K. Pharmacological inhibition of sphingolipid synthesis reduces ferroptosis by stimulating the HIF-1 pathway. iScience 2022; 25:104533. [PMID: 35784791 PMCID: PMC9240796 DOI: 10.1016/j.isci.2022.104533] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 03/04/2022] [Accepted: 06/01/2022] [Indexed: 02/07/2023] Open
Affiliation(s)
- Yang Liu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065 Sichuan, P.R.China
| | - Libo He
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065 Sichuan, P.R.China
| | - Binghua Liu
- Laboratory of Molecular Biology, College of Medicine, Chengdu University, Chengdu 610106 Sichuan, P. R. China
| | - Yuling Ying
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065 Sichuan, P.R.China
| | - Junling Xu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065 Sichuan, P.R.China
| | - Meng Yu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065 Sichuan, P.R.China
| | - Jinye Dang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065 Sichuan, P.R.China
| | - Ke Liu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065 Sichuan, P.R.China
- Corresponding author
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20
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Ruffini N, Klingenberg S, Heese R, Schweiger S, Gerber S. The Big Picture of Neurodegeneration: A Meta Study to Extract the Essential Evidence on Neurodegenerative Diseases in a Network-Based Approach. Front Aging Neurosci 2022; 14:866886. [PMID: 35832065 PMCID: PMC9271745 DOI: 10.3389/fnagi.2022.866886] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 05/13/2022] [Indexed: 12/12/2022] Open
Abstract
The common features of all neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, Amyotrophic Lateral Sclerosis (ALS), and Huntington's disease, are the accumulation of aggregated and misfolded proteins and the progressive loss of neurons, leading to cognitive decline and locomotive dysfunction. Still, they differ in their ultimate manifestation, the affected brain region, and the kind of proteinopathy. In the last decades, a vast number of processes have been described as associated with neurodegenerative diseases, making it increasingly harder to keep an overview of the big picture forming from all those data. In this meta-study, we analyzed genomic, transcriptomic, proteomic, and epigenomic data of the aforementioned diseases using the data of 234 studies in a network-based approach to study significant general coherences but also specific processes in individual diseases or omics levels. In the analysis part, we focus on only some of the emerging findings, but trust that the meta-study provided here will be a valuable resource for various other researchers focusing on specific processes or genes contributing to the development of neurodegeneration.
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Affiliation(s)
- Nicolas Ruffini
- Institute of Human Genetics, University Medical Center, Johannes Gutenberg University, Mainz, Germany
- Leibniz Institute for Resilience Research, Leibniz Association, Mainz, Germany
| | - Susanne Klingenberg
- Institute of Human Genetics, University Medical Center, Johannes Gutenberg University, Mainz, Germany
| | - Raoul Heese
- Fraunhofer Institute for Industrial Mathematics (ITWM), Kaiserslautern, Germany
| | - Susann Schweiger
- Institute of Human Genetics, University Medical Center, Johannes Gutenberg University, Mainz, Germany
| | - Susanne Gerber
- Institute of Human Genetics, University Medical Center, Johannes Gutenberg University, Mainz, Germany
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21
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D’Souza Z, Sumya FT, Khakurel A, Lupashin V. Getting Sugar Coating Right! The Role of the Golgi Trafficking Machinery in Glycosylation. Cells 2021; 10:cells10123275. [PMID: 34943782 PMCID: PMC8699264 DOI: 10.3390/cells10123275] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 12/18/2022] Open
Abstract
The Golgi is the central organelle of the secretory pathway and it houses the majority of the glycosylation machinery, which includes glycosylation enzymes and sugar transporters. Correct compartmentalization of the glycosylation machinery is achieved by retrograde vesicular trafficking as the secretory cargo moves forward by cisternal maturation. The vesicular trafficking machinery which includes vesicular coats, small GTPases, tethers and SNAREs, play a major role in coordinating the Golgi trafficking thereby achieving Golgi homeostasis. Glycosylation is a template-independent process, so its fidelity heavily relies on appropriate localization of the glycosylation machinery and Golgi homeostasis. Mutations in the glycosylation enzymes, sugar transporters, Golgi ion channels and several vesicle tethering factors cause congenital disorders of glycosylation (CDG) which encompass a group of multisystem disorders with varying severities. Here, we focus on the Golgi vesicle tethering and fusion machinery, namely, multisubunit tethering complexes and SNAREs and their role in Golgi trafficking and glycosylation. This review is a comprehensive summary of all the identified CDG causing mutations of the Golgi trafficking machinery in humans.
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22
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Sphingolipid metabolism governs Purkinje cell patterned degeneration in Atxn1[82Q]/+ mice. Proc Natl Acad Sci U S A 2021; 118:2016969118. [PMID: 34479994 PMCID: PMC8433568 DOI: 10.1073/pnas.2016969118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 07/19/2021] [Indexed: 01/02/2023] Open
Abstract
Neuronal subtypes are differentially affected by neuropathologies. For example, Purkinje cells, the principal neurons of the cerebellum, can be divided in subpopulations based on their sensitivity to pathological insult. However, the molecular mechanisms explaining why, among seemingly identical neurons, some will degenerate while others survive remain unknown. Here, we analyzed, in a disease model of cerebellar neurodegeneration, the metabolism of sphingolipids, complex lipids involved in cell apoptosis, and found that specific sphingolipids accumulate in the cerebellar region primarily affected by neurodegeneration. Preventing this accumulation by disrupting sphingolipid metabolism via genetic mutation caused a neuroprotective effect on subpopulations of Purkinje cells. Thus, our data indicate that sphingolipid metabolism is involved in the predisposition of neuronal subtypes to neurodegeneration. Patterned degeneration of Purkinje cells (PCs) can be observed in a wide range of neuropathologies, but mechanisms behind nonrandom cerebellar neurodegeneration remain unclear. Sphingolipid metabolism dyshomeostasis typically leads to PC neurodegeneration; hence, we questioned whether local sphingolipid balance underlies regional sensitivity to pathological insults. Here, we investigated the regional compartmentalization of sphingolipids and their related enzymes in the cerebellar cortex in healthy and pathological conditions. Analysis in wild-type animals revealed higher sphingosine kinase 1 (Sphk1) levels in the flocculonodular cerebellum, while sphingosine-1-phosphate (S1P) levels were higher in the anterior cerebellum. Next, we investigated a model for spinocerebellar ataxia type 1 (SCA1) driven by the transgenic expression of the expanded Ataxin 1 protein with 82 glutamine (82Q), exhibiting severe PC degeneration in the anterior cerebellum while the flocculonodular region is preserved. In Atxn1[82Q]/+ mice, we found that levels of Sphk1 and Sphk2 were region-specific decreased and S1P levels increased, particularly in the anterior cerebellum. To determine if there is a causal link between sphingolipid levels and neurodegeneration, we deleted the Sphk1 gene in Atxn1[82Q]/+ mice. Analysis of Atxn1[82Q]/+; Sphk1−/− mice confirmed a neuroprotective effect, rescuing a subset of PCs in the anterior cerebellum, in domains reminiscent of the modules defined by AldolaseC expression. Finally, we showed that Sphk1 deletion acts on the ATXN1[82Q] protein expression and prevents PC degeneration. Taken together, our results demonstrate that there are regional differences in sphingolipid metabolism and that this metabolism is directly involved in PC degeneration in Atxn1[82Q]/+ mice.
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Khakurel A, Kudlyk T, Bonifacino JS, Lupashin VV. The Golgi-associated retrograde protein (GARP) complex plays an essential role in the maintenance of the Golgi glycosylation machinery. Mol Biol Cell 2021; 32:1594-1610. [PMID: 34161137 PMCID: PMC8351751 DOI: 10.1091/mbc.e21-04-0169] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/24/2021] [Accepted: 06/14/2021] [Indexed: 11/18/2022] Open
Abstract
The Golgi complex is a central hub for intracellular protein trafficking and glycosylation. Steady-state localization of glycosylation enzymes is achieved by a combination of mechanisms involving retention and recycling, but the machinery governing these mechanisms is poorly understood. Herein we show that the Golgi-associated retrograde protein (GARP) complex is a critical component of this machinery. Using multiple human cell lines, we show that depletion of GARP subunits impairs Golgi modification of N- and O-glycans and reduces the stability of glycoproteins and Golgi enzymes. Moreover, GARP-knockout (KO) cells exhibit reduced retention of glycosylation enzymes in the Golgi. A RUSH assay shows that, in GARP-KO cells, the enzyme beta-1,4-galactosyltransferase 1 is not retained at the Golgi complex but instead is missorted to the endolysosomal system. We propose that the endosomal system is part of the trafficking itinerary of Golgi enzymes or their recycling adaptors and that the GARP complex is essential for recycling and stabilization of the Golgi glycosylation machinery. [Media: see text].
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Affiliation(s)
- Amrita Khakurel
- University of Arkansas for Medical Sciences, Department of Physiology and Cell Biology, Little Rock, AR 72205
| | - Tetyana Kudlyk
- University of Arkansas for Medical Sciences, Department of Physiology and Cell Biology, Little Rock, AR 72205
| | - Juan S. Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
| | - Vladimir V. Lupashin
- University of Arkansas for Medical Sciences, Department of Physiology and Cell Biology, Little Rock, AR 72205
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24
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Mondal K, Takahashi H, Cole J, Del Mar NA, Li C, Stephenson DJ, Allegood J, Cowart LA, Chalfant CE, Reiner A, Mandal N. Systemic Elevation of n-3 Polyunsaturated Fatty Acids (n-3-PUFA) Is Associated with Protection against Visual, Motor, and Emotional Deficits in Mice following Closed-Head Mild Traumatic Brain Injury. Mol Neurobiol 2021; 58:5564-5580. [PMID: 34365584 DOI: 10.1007/s12035-021-02501-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 07/17/2021] [Indexed: 12/30/2022]
Abstract
Traumatic brain injury (TBI) causes neuroinflammation and neurodegeneration leading to various pathological complications such as motor and sensory (visual) deficits, cognitive impairment, and depression. N-3 polyunsaturated fatty acid (n-3 PUFA) containing lipids are known to be anti-inflammatory, whereas the sphingolipid, ceramide (Cer), is an inducer of neuroinflammation and degeneration. Using Fat1+-transgenic mice that contain elevated levels of systemic n-3 PUFA, we tested whether they are resistant to mild TBI-mediated sensory-motor and emotional deficits by subjecting Fat1-transgenic mice and their WT littermates to focal cranial air blast (50 psi) or sham blast (0 psi, control). We observed that visual function in WT mice was reduced significantly following TBI but not in Fat1+-blast animals. We also found Fat1+-blast mice were resistant to the decline in motor functions, depression, and fear-producing effects of blast, as well as the reduction in the area of oculomotor nucleus and increase in activated microglia in the optic tract in brain sections seen following blast in WT mice. Lipid and gene expression analyses confirmed an elevated level of the n-3 PUFA eicosapentaenoic acid (EPA) in the plasma and brain, blocking of TBI-mediated increase of Cer in the brain, and decrease in TBI-mediated induction of Cer biosynthetic and inflammatory gene expression in the brain of the Fat1+ mice. Our results demonstrate that suppression of ceramide biosynthesis and inflammatory factors in Fat1+-transgenic mice is associated with significant protection against the visual, motor, and emotional deficits caused by mild TBI. This study suggests that n-3 PUFA (especially, EPA) has a promising therapeutic role in preventing neurodegeneration after TBI.
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Affiliation(s)
- Koushik Mondal
- Department of Ophthalmology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA
| | - Haruka Takahashi
- Department of Ophthalmology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA.,Department of Animal Science, Iwate University, Morioka, Japan
| | - Jerome Cole
- Department of Ophthalmology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA
| | - Nobel A Del Mar
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA
| | - Chunyan Li
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA
| | - Daniel J Stephenson
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, 33620, USA
| | - Jeremy Allegood
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA, 23219, USA
| | - L Ashley Cowart
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA, 23219, USA.,Hunter Holmes McGuire VA Medical Center, Richmond, VA, 23249, USA
| | - Charles E Chalfant
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, 33620, USA.,The Moffitt Cancer Center, Tampa, FL, 33620, USA.,Research Service, James A. Haley Veterans Hospital, Tampa, FL, 33612, USA
| | - Anton Reiner
- Department of Ophthalmology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA.,Department of Anatomy and Neurobiology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA
| | - Nawajes Mandal
- Department of Ophthalmology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA. .,Department of Anatomy and Neurobiology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA. .,Department of Pharmaceutical Sciences, College of Pharmacy, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA. .,Memphis VA Medical Center, Memphis, TN, 38104, USA.
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25
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The Novel Regulatory Role of lncRNA-miRNA-mRNA Axis in Amyotrophic Lateral Sclerosis: An Integrated Bioinformatics Analysis. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2021; 2021:5526179. [PMID: 33953791 PMCID: PMC8067776 DOI: 10.1155/2021/5526179] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/02/2021] [Accepted: 03/05/2021] [Indexed: 01/18/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease that primarily affects motor neurons, causing muscle atrophy, bulbar palsy, and pyramidal tract signs. However, the aetiology and pathogenesis of ALS have not been elucidated to date. In this study, a competitive endogenous RNA (ceRNA) network was constructed by analyzing the expression profiles of messenger RNAs (mRNAs) and long noncoding RNAs (lncRNAs) that were matched by 7 ALS samples and 4 control samples, and then a protein-protein interaction (PPI) network was constructed to identify the genes related to ALS. Gene Ontology (GO) was used to study the potential functions of differentially expressed mRNAs (DEmRNAs) in the ceRNA network. For the ALS and control groups, 247177 potential lncRNA-mRNA ceRNA relationship pairs were screened. Analysis of significant relationship pairs demonstrated that the PPI modules formed by the MALAT1-regulated SYNRG, ITSN2, PICALM, AP3B1, and AAK1 genes may play important roles in the pathogenesis of ALS, and these results may help to characterize the pathogenesis of ALS.
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26
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Hepowit NL, Macedo JKA, Young LEA, Liu K, Sun RC, MacGurn JA, Dickson RC. Enhancing lifespan of budding yeast by pharmacological lowering of amino acid pools. Aging (Albany NY) 2021; 13:7846-7871. [PMID: 33744865 PMCID: PMC8034917 DOI: 10.18632/aging.202849] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/21/2021] [Indexed: 04/20/2023]
Abstract
The increasing prevalence of age-related diseases and resulting healthcare insecurity and emotional burden require novel treatment approaches. Several promising strategies seek to limit nutrients and promote healthy aging. Unfortunately, the human desire to consume food means this strategy is not practical for most people but pharmacological approaches might be a viable alternative. We previously showed that myriocin, which impairs sphingolipid synthesis, increases lifespan in Saccharomyces cerevisiae by modulating signaling pathways including the target of rapamycin complex 1 (TORC1). Since TORC1 senses cellular amino acids, we analyzed amino acid pools and identified 17 that are lowered by myriocin treatment. Studying the methionine transporter, Mup1, we found that newly synthesized Mup1 traffics to the plasma membrane and is stable for several hours but is inactive in drug-treated cells. Activity can be restored by adding phytosphingosine to culture medium thereby bypassing drug inhibition, thus confirming a sphingolipid requirement for Mup1 activity. Importantly, genetic analysis of myriocin-induced longevity revealed a requirement for the Gtr1/2 (mammalian Rags) and Vps34-Pib2 amino acid sensing pathways upstream of TORC1, consistent with a mechanism of action involving decreased amino acid availability. These studies demonstrate the feasibility of pharmacologically inducing a state resembling amino acid restriction to promote healthy aging.
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Affiliation(s)
- Nathaniel L. Hepowit
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Jessica K. A. Macedo
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA
| | - Lyndsay E. A. Young
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Ke Liu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, Sichuan University, Chengdu 610000, Sichuan, P. R. China
| | - Ramon C. Sun
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA
- Department of Neuroscience, University of Kentucky, Lexington, KY 40536, USA
| | - Jason A. MacGurn
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Robert C. Dickson
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
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