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Keenen MM, Yang L, Liang H, Farmer VJ, Singh R, Gladfelter AS, Coyne CB. Comparative analysis of the syncytiotrophoblast in placenta tissue and trophoblast organoids using snRNA sequencing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.01.601571. [PMID: 39005304 PMCID: PMC11244908 DOI: 10.1101/2024.07.01.601571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
The outer surface of chorionic villi in the human placenta consists of a single multinucleated cell called the syncytiotrophoblast (STB). The unique cellular ultrastructure of the STB presents challenges in deciphering its gene expression signature at the single-cell level, as the STB contains billions of nuclei in a single cell. There are many gaps in understanding the molecular mechanisms and developmental trajectories involved in STB formation and differentiation. To identify the underlying control of the STB, we performed comparative single nucleus (SN) and single cell (SC) RNA sequencing on placental tissue and tissue-derived trophoblast organoids (TOs). We found that SN was essential to capture the STB population from both tissue and TOs. Differential gene expression and pseudotime analysis of TO-derived STB identified three distinct nuclear subtypes reminiscent of those recently identified in vivo . These included a juvenile nuclear population that exhibited both CTB and STB marker expression, a population enriched in genes involved in oxygen sensing, and a fully differentiated subtype. Notably, suspension culture conditions of TOs that restore the native orientation of the STB (STB out ) showed elevated expression of canonical STB markers and pregnancy hormones, along with a greater proportion of the terminally differentiated mature STB subtype, compared to those cultivated with an inverted STB polarity (STB in ). Gene regulatory analysis identified novel markers of STB differentiation conserved in tissue and TOs, including the chromatin remodeler RYBP, that exhibited STB-specific RNA and protein expression. Finally, we compared STB gene expression signatures amongst first trimester tissue, full-term tissue, and TOs, identifying many commonalities but also notable variability across each sample type. This indicates that STB gene expression is responsive to its environmental context. Our findings emphasize the utility of TOs to accurately model STB differentiation and the distinct nuclear subtypes observed in vivo , offering a versatile platform for unraveling the molecular mechanisms governing STB functions in placental biology and disease.
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Li L, Lixia D, Gan G, Li J, Yang L, Wu Y, Fang Z, Zhang X. Astrocytic HILPDA promotes lipid droplets generation to drive cognitive dysfunction in mice with sepsis-associated encephalopathy. CNS Neurosci Ther 2024; 30:e14758. [PMID: 38757390 PMCID: PMC11099789 DOI: 10.1111/cns.14758] [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: 12/18/2023] [Revised: 04/20/2024] [Accepted: 04/23/2024] [Indexed: 05/18/2024] Open
Abstract
AIMS Sepsis-associated encephalopathy (SAE) is manifested as a spectrum of disturbed cerebral function ranging from mild delirium to coma. However, the pathogenesis of SAE has not been clearly elucidated. Astrocytes play important roles in maintaining the function and metabolism of the brain. Most recently, it has been demonstrated that disorders of lipid metabolism, especially lipid droplets (LDs) dyshomeostasis, are involved in a variety of neurodegenerative diseases. The aim of this study was to investigate whether LDs are involved in the underlying mechanism of SAE. METHODS The open field test, Y-maze test, and contextual fear conditioning test (CFCT) were used to test cognitive function in SAE mice. Lipidomics was utilized to investigate alterations in hippocampal lipid metabolism in SAE mice. Western blotting and immunofluorescence labeling were applied for the observation of related proteins. RESULTS In the current study, we found that SAE mice showed severe cognitive dysfunction, including spatial working and contextual memory. Meanwhile, we demonstrated that lipid metabolism was widely dysregulated in the hippocampus by using lipidomic analysis. Furthermore, western blotting and immunofluorescence confirmed that LDs accumulation in hippocampal astrocytes was involved in the pathological process of cognitive dysfunction in SAE mice. We verified that LDs can be inhibited by specifically suppress hypoxia-inducible lipid droplet-associated protein (HILPDA) in astrocytes. Meanwhile, cognitive dysfunction in SAE was ameliorated by reducing A1 astrocyte activation and inhibiting presynaptic membrane transmitter release. CONCLUSION The accumulation of astrocytic lipid droplets plays a crucial role in the pathological process of SAE. HILPDA is an attractive therapeutic target for lipid metabolism regulation and cognitive improvement in septic patients.
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Affiliation(s)
- Ling Li
- Department of Critical Care MedicineXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
- Department of Anesthesiology and Perioperative Medicine and Department of Intensive Care UnitXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
- Department of PediatricXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
| | - Du Lixia
- Department of Critical Care MedicineXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
- Department of Anesthesiology and Perioperative Medicine and Department of Intensive Care UnitXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
| | - Guifen Gan
- Department of Critical Care MedicineQinghai University Affiliated HospitalXiningQinghaiChina
| | - Jin Li
- Department of Critical Care MedicineXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
- Department of Anesthesiology and Perioperative Medicine and Department of Intensive Care UnitXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
| | - Lin Yang
- Department of Critical Care MedicineXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
- Department of Anesthesiology and Perioperative Medicine and Department of Intensive Care UnitXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
| | - You Wu
- Department of Critical Care MedicineXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
- Department of Anesthesiology and Perioperative Medicine and Department of Intensive Care UnitXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
| | - Zongping Fang
- Department of Critical Care MedicineXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
- Department of Anesthesiology and Perioperative Medicine and Department of Intensive Care UnitXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
- Translational Research Institute of Brain and Brain‐Like IntelligenceShanghai Fourth People's HospitalSchool of MedicineTongji UniversityShanghaiChina
- Department of Critical Care MedicineShanghai Fourth People's HospitalSchool of MedicineTongji UniversityShanghaiChina
| | - Xijing Zhang
- Department of Critical Care MedicineXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
- Department of Anesthesiology and Perioperative Medicine and Department of Intensive Care UnitXijing HospitalFourth Military Medical UniversityXi'anShaanxiChina
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Deng B, Kong W, Shen X, Han C, Zhao Z, Chen S, Zhou C, Bae-Jump V. The role of DGAT1 and DGAT2 in regulating tumor cell growth and their potential clinical implications. J Transl Med 2024; 22:290. [PMID: 38500157 PMCID: PMC10946154 DOI: 10.1186/s12967-024-05084-z] [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: 12/20/2023] [Accepted: 03/10/2024] [Indexed: 03/20/2024] Open
Abstract
Lipid metabolism is widely reprogrammed in tumor cells. Lipid droplet is a common organelle existing in most mammal cells, and its complex and dynamic functions in maintaining redox and metabolic balance, regulating endoplasmic reticulum stress, modulating chemoresistance, and providing essential biomolecules and ATP have been well established in tumor cells. The balance between lipid droplet formation and catabolism is critical to maintaining energy metabolism in tumor cells, while the process of energy metabolism affects various functions essential for tumor growth. The imbalance of synthesis and catabolism of fatty acids in tumor cells leads to the alteration of lipid droplet content in tumor cells. Diacylglycerol acyltransferase 1 and diacylglycerol acyltransferase 2, the enzymes that catalyze the final step of triglyceride synthesis, participate in the formation of lipid droplets in tumor cells and in the regulation of cell proliferation, migration and invasion, chemoresistance, and prognosis in tumor. Several diacylglycerol acyltransferase 1 and diacylglycerol acyltransferase 2 inhibitors have been developed over the past decade and have shown anti-tumor effects in preclinical tumor models and improvement of metabolism in clinical trials. In this review, we highlight key features of fatty acid metabolism and different paradigms of diacylglycerol acyltransferase 1 and diacylglycerol acyltransferase 2 activities on cell proliferation, migration, chemoresistance, and prognosis in tumor, with the hope that these scientific findings will have potential clinical implications.
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Affiliation(s)
- Boer Deng
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, People's Republic of China
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Weimin Kong
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, People's Republic of China
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Xiaochang Shen
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, People's Republic of China
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Chao Han
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, People's Republic of China
| | - Ziyi Zhao
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, People's Republic of China
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Shuning Chen
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, People's Republic of China
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Chunxiao Zhou
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
| | - Victoria Bae-Jump
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
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Cui Y, Man S, Tao J, Liu Y, Ma L, Guo L, Huang L, Liu C, Gao W. The lipid droplet in cancer: From being a tumor-supporting hallmark to clinical therapy. Acta Physiol (Oxf) 2024; 240:e14087. [PMID: 38247395 DOI: 10.1111/apha.14087] [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: 08/27/2023] [Revised: 10/18/2023] [Accepted: 01/01/2024] [Indexed: 01/23/2024]
Abstract
INTRODUCTION Abnormal lipid metabolism, one of the hallmarks in cancer, has gradually emerged as a novel target for cancer treatment. As organelles that store and release excess lipids, lipid droplets (LDs) resemble "gears" and facilitate cancer development in the body. AIM This review discusses the life cycle of LDs, the relationship between abnormal LDs and cancer hallmarks, and the application of LDs in theragnostic and clinical contexts to provide a contemporary understanding of the role of LDs in cancer. METHODS A systematic literature search was conducted in PubMed and SPORTDiscus. Retrieve and summarize clinical trials of drugs that target proteins associated with LD formation using the Clinical Trials website. Create a schematic diagram of lipid droplets in the tumor microenvironment using Adobe Illustrator. CONCLUSION As one of the top ten hallmarks of cancer, abnormal lipid metabolism caused by excessive generation of LDs interrelates with other hallmarks. The crosstalk between excessive LDs and intracellular free fatty acids (FFAs) promotes an inflammatory environment that supports tumor growth. Moreover, LDs contribute to cancer metastasis and cell death resistance in vivo. Statins, as HMGCR inhibitors, are promising to be the pioneering commercially available anti-cancer drugs that target LD formation.
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Affiliation(s)
- Yingfang Cui
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Key Laboratory of Industry Microbiology, National and Local United Engineering Lab of Metabolic Control Fermentation Technology, China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Shuli Man
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Key Laboratory of Industry Microbiology, National and Local United Engineering Lab of Metabolic Control Fermentation Technology, China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Jiejing Tao
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Key Laboratory of Industry Microbiology, National and Local United Engineering Lab of Metabolic Control Fermentation Technology, China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Yu Liu
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Key Laboratory of Industry Microbiology, National and Local United Engineering Lab of Metabolic Control Fermentation Technology, China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Long Ma
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Key Laboratory of Industry Microbiology, National and Local United Engineering Lab of Metabolic Control Fermentation Technology, China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Lanping Guo
- National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| | - Luqi Huang
- National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| | - Changxiao Liu
- State Key Laboratory of Drug Release Technology and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research Co and Ltd., Tianjin, China
| | - Wenyuan Gao
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
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Kamińska D, Skrzycki M. Lipid droplets, autophagy, and ER stress as key (survival) pathways during ischemia-reperfusion of transplanted grafts. Cell Biol Int 2024; 48:253-279. [PMID: 38178581 DOI: 10.1002/cbin.12114] [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: 07/13/2023] [Revised: 11/30/2023] [Accepted: 12/14/2023] [Indexed: 01/06/2024]
Abstract
Ischemia-reperfusion injury is an event concerning any organ under a procedure of transplantation. The early result of ischemia is hypoxia, which causes malfunction of mitochondria and decrease in cellular ATP. This leads to disruption of cellular metabolism. Reperfusion also results in cell damage due to reoxygenation and increased production of reactive oxygen species, and later by induced inflammation. In damaged and hypoxic cells, the endoplasmic reticulum (ER) stress pathway is activated by increased amount of damaged or misfolded proteins, accumulation of free fatty acids and other lipids due to inability of their oxidation (lipotoxicity). ER stress is an adaptive response and a survival pathway, however, its prolonged activity eventually lead to induction of apoptosis. Sustaining cell functionality in stress conditions is a great challenge for transplant surgeons as it is crucial for maintaining a desired level of graft vitality. Pathways counteracting negative consequences of ischemia-reperfusion are autophagy and lipid droplets (LD) metabolism. Autophagy remove damaged organelles and molecules driving them to lysosomes, digested simpler compounds are energy source for the cell. Mitophagy and ER-phagy results in improvement of cell energetic balance and alleviation of ER stress. This is important in sustaining metabolic homeostasis and thus cell survival. LD metabolism is connected with autophagy as LD are degraded by lipophagy, a source of free fatty acids and glycerol-thus autophagy and LD can readily remove lipotoxic compounds in the cell. In conclusion, monitoring and pharmaceutic regulation of those pathways during transplantation procedure might result in increased/improved vitality of transplanted organ.
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Affiliation(s)
- Daria Kamińska
- Department of Radiotherapy, Maria Sklodowska-Curie National Research Institute of Oncology, Warszawa, Poland
| | - Michał Skrzycki
- Chair and Department of Biochemistry, Medical University of Warsaw, Warszawa, Poland
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Lawrence ES, Gu W, Bohlender RJ, Anza-Ramirez C, Cole AM, Yu JJ, Hu H, Heinrich EC, O’Brien KA, Vasquez CA, Cowan QT, Bruck PT, Mercader K, Alotaibi M, Long T, Hall JE, Moya EA, Bauk MA, Reeves JJ, Kong MC, Salem RM, Vizcardo-Galindo G, Macarlupu JL, Figueroa-Mujíca R, Bermudez D, Corante N, Gaio E, Fox KP, Salomaa V, Havulinna AS, Murray AJ, Malhotra A, Powel FL, Jain M, Komor AC, Cavalleri GL, Huff CD, Villafuerte FC, Simonson TS. Functional EPAS1/ HIF2A missense variant is associated with hematocrit in Andean highlanders. SCIENCE ADVANCES 2024; 10:eadj5661. [PMID: 38335297 PMCID: PMC10857371 DOI: 10.1126/sciadv.adj5661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 01/10/2024] [Indexed: 02/12/2024]
Abstract
Hypoxia-inducible factor pathway genes are linked to adaptation in both human and nonhuman highland species. EPAS1, a notable target of hypoxia adaptation, is associated with relatively lower hemoglobin concentration in Tibetans. We provide evidence for an association between an adaptive EPAS1 variant (rs570553380) and the same phenotype of relatively low hematocrit in Andean highlanders. This Andean-specific missense variant is present at a modest frequency in Andeans and absent in other human populations and vertebrate species except the coelacanth. CRISPR-base-edited human cells with this variant exhibit shifts in hypoxia-regulated gene expression, while metabolomic analyses reveal both genotype and phenotype associations and validation in a lowland population. Although this genocopy of relatively lower hematocrit in Andean highlanders parallels well-replicated findings in Tibetans, it likely involves distinct pathway responses based on a protein-coding versus noncoding variants, respectively. These findings illuminate how unique variants at EPAS1 contribute to the same phenotype in Tibetans and a subset of Andean highlanders despite distinct evolutionary trajectories.
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Affiliation(s)
- Elijah S. Lawrence
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Wanjun Gu
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Ryan J. Bohlender
- Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Cecilia Anza-Ramirez
- Laboratorio de Fisiología Comparada/Fisiología de del Transporte de Oxígeno-LID, Departamento de Ciencias Biológicas y Fisiológicas, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Amy M. Cole
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - James J. Yu
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Hao Hu
- Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Erica C. Heinrich
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, USA
| | - Katie A. O’Brien
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK
| | - Carlos A. Vasquez
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Quinn T. Cowan
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Patrick T. Bruck
- Department of Anthropology and Global Health, University of California, San Diego, La Jolla, CA, USA
| | - Kysha Mercader
- Department of Medicine and Pharmacology, University of California, San Diego, La Jolla, CA, USA
| | - Mona Alotaibi
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
- Department of Medicine and Pharmacology, University of California, San Diego, La Jolla, CA, USA
| | - Tao Long
- Department of Medicine and Pharmacology, University of California, San Diego, La Jolla, CA, USA
- Sapient Bioanalytics, LLC, San Diego, CA, USA
| | - James E. Hall
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Esteban A. Moya
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Marco A. Bauk
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Jennifer J. Reeves
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Mitchell C. Kong
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA
| | - Rany M. Salem
- Herbert Wertheim School of Public Health and Longevity Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Gustavo Vizcardo-Galindo
- Laboratorio de Fisiología Comparada/Fisiología de del Transporte de Oxígeno-LID, Departamento de Ciencias Biológicas y Fisiológicas, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Jose-Luis Macarlupu
- Laboratorio de Fisiología Comparada/Fisiología de del Transporte de Oxígeno-LID, Departamento de Ciencias Biológicas y Fisiológicas, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Rómulo Figueroa-Mujíca
- Laboratorio de Fisiología Comparada/Fisiología de del Transporte de Oxígeno-LID, Departamento de Ciencias Biológicas y Fisiológicas, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Daniela Bermudez
- Laboratorio de Fisiología Comparada/Fisiología de del Transporte de Oxígeno-LID, Departamento de Ciencias Biológicas y Fisiológicas, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Noemi Corante
- Laboratorio de Fisiología Comparada/Fisiología de del Transporte de Oxígeno-LID, Departamento de Ciencias Biológicas y Fisiológicas, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Eduardo Gaio
- Laboratório de Fisiologia Respiratória, Faculdade de Medicina, Universidade de Brasília, Brasília, Brazil
| | - Keolu P. Fox
- Department of Anthropology and Global Health, University of California, San Diego, La Jolla, CA, USA
| | - Veikko Salomaa
- Department of Public Health and Welfare, Finnish Institute for Health and Welfare, Helsinki, Finland
| | - Aki S. Havulinna
- Department of Public Health and Welfare, Finnish Institute for Health and Welfare, Helsinki, Finland
- Institute for Molecular Medicine Finland (FIMM-HiLIFE), Helsinki, Finland
| | - Andrew J. Murray
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK
| | - Atul Malhotra
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Frank L. Powel
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Mohit Jain
- Department of Medicine and Pharmacology, University of California, San Diego, La Jolla, CA, USA
- Sapient Bioanalytics, LLC, San Diego, CA, USA
| | - Alexis C. Komor
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Gianpiero L. Cavalleri
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Chad D. Huff
- Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Francisco C. Villafuerte
- Laboratorio de Fisiología Comparada/Fisiología de del Transporte de Oxígeno-LID, Departamento de Ciencias Biológicas y Fisiológicas, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Tatum S. Simonson
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, Department of Medicine, University of California, San Diego, La Jolla, CA, USA
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Hass DT, Zhang Q, Autterson GA, Bryan RA, Hurley JB, Miller JML. Medium Depth Influences O2 Availability and Metabolism in Human RPE Cultures. Invest Ophthalmol Vis Sci 2023; 64:4. [PMID: 37922158 PMCID: PMC10629522 DOI: 10.1167/iovs.64.14.4] [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: 05/14/2023] [Accepted: 10/13/2023] [Indexed: 11/05/2023] Open
Abstract
Purpose Retinal pigment epithelium (RPE) oxidative metabolism is critical for normal retinal function and is often studied in cell culture systems. Here, we show that conventional culture media volumes dramatically impact O2 availability, limiting oxidative metabolism. We suggest optimal conditions to ensure cultured RPE is in a normoxic environment permissive to oxidative metabolism. Methods We altered the availability of O2 to human primary and induced pluripotent stem cell-derived RPE cultures directly via a hypoxia chamber or indirectly via the amount of medium over cells. We measured oxygen consumption rates (OCRs), glucose consumption, lactate production, 13C6-glucose and 13C5-glutamine flux, hypoxia inducible factor 1α (HIF-1α) stability, intracellular lipid droplets after a lipid challenge, transepithelial electrical resistance, cell morphology, and pigmentation. Results Medium volumes commonly employed during RPE culture limit diffusion of O2 to cells, triggering hypoxia, activating HIF-1α, limiting OCR, and dramatically altering cell metabolism, with only minor effects on typical markers of RPE health. Media volume effects on O2 availability decrease acetyl-CoA utilization, increase glycolysis and reductive carboxylation, and alter the size and number of intracellular lipid droplets under lipid-rich conditions. Conclusions Despite having little impact on visible and typical markers of RPE culture health, media volume dramatically affects RPE physiology "under the hood." As RPE-centric diseases like age-related macular degeneration involve oxidative metabolism, RPE cultures need to be optimized to study such diseases. We provide guidelines for optimal RPE culture volumes that balance ample nutrient availability from larger media volumes with adequate O2 availability seen with smaller media volumes.
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Affiliation(s)
- Daniel T. Hass
- Department of Biochemistry, The University of Washington, Seattle, Washington, United States
| | - Qitao Zhang
- Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, United States
| | | | | | - James B. Hurley
- Department of Biochemistry, The University of Washington, Seattle, Washington, United States
| | - Jason M. L. Miller
- Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, United States
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, Michigan, United States
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Wang X, Zou A, Zhang J, Gao G, Shan W, Li J, Liu X. High expression of HILPDA is an adverse prognostic prognostic factor in hepatocellular carcinoma. Medicine (Baltimore) 2023; 102:e33145. [PMID: 36862910 PMCID: PMC9981432 DOI: 10.1097/md.0000000000033145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/04/2023] Open
Abstract
Hepatocellular carcinoma (LIHC) is a malignant tumor arising from hepatocytes or intrahepatic bile duct epithelial cells, which is one of the common malignancies worldwide. Better identification of liver cancer biomarkers has become one of the current challenges. Although hypoxia inducible lipid droplet associated (HILPDA) has been reported to be associated with tumor progression in a variety of human solid cancers, it has rarely been reported in the field of hepatocellular carcinoma; therefore, in this paper, RNA sequencing data from TCGA were used to analyze the expression of HILPDA and differentially expressed genes (DEGs). In addition, functional enrichment analysis of HILPDA-associated DEGs was performed by GO/KEGG, GSEA, immune cell infiltration analysis and protein-protein interaction network. The clinical significance of HILPDA in LIHC was calculated by Kaplan-Meier Cox regression and prognostic nomogram models. R package was used to analyze the combined studies. Thus, HILPDA was highly expressed in various malignancies, including LIHC, compared with normal samples, and high HILPDA expression was associated with poor prognosis (P < .05). Cox regression analysis showed high HILPDA to be an independent prognostic factor; age and cytogenetic risk were included in the nomogram prognostic model. A total of 1294 DEGs were identified between the high and low expression groups, of which 1169 had upregulated gene expression and 125 had downregulated gene expression. Overall, high expression of HILPDA is a potential biomarker for poor outcome in LIHC.
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Affiliation(s)
- Xiao Wang
- Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Aoshuang Zou
- Guangzhou University of Traditional Chinese Medicine, Guangzhou, China
| | - Jinhe Zhang
- Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Guochuan Gao
- Guangzhou University of Traditional Chinese Medicine, Guangzhou, China
| | - Wenting Shan
- Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Jun Li
- Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Xia Liu
- Guizhou University of Traditional Chinese Medicine, Guiyang, China
- *Correspondence: Xia Liu, Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou 550025, China (e-mail: )
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Quantitative Phase Imaging Detecting the Hypoxia-Induced Patterns in Healthy and Neoplastic Human Colonic Epithelial Cells. Cells 2022; 11:cells11223599. [PMID: 36429026 PMCID: PMC9688862 DOI: 10.3390/cells11223599] [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: 09/21/2022] [Revised: 11/08/2022] [Accepted: 11/11/2022] [Indexed: 11/16/2022] Open
Abstract
Hypoxia is a frequent phenomenon during carcinogenesis and may lead to functional and structural changes in proliferating cancer cells. Colorectal cancer (CRC) is one of the most common neoplasms in which hypoxia is associated with progression. The aim of this study was to assess the optical parameters and microanatomy of CRC and the normal intestinal epithelium cells using the digital holotomography (DHT) method. The examination was conducted on cancer (HT-29, LoVo) and normal colonic cells (CCD-18Co) cultured in normoxic and hypoxic environments. The assessment included optical parameters such as the refractive index (RI) and dry mass as well as the morphological features. Hypoxia decreased the RI in all cells as well as in their cytoplasm, nucleus, and nucleoli. The opposite tendency was noted for spheroid-vesicular structures, where the RI was higher for the hypoxic state. The total volume of hypoxic CCD-18Co and LoVo cells was decreased, while an increase in this parameter was observed for HT-29 cells. Hypoxia increased the radius and cell volume, including the dry mass of the vesicular content. The changes in the optics and morphology of hypoxic cells may suggest the possibility of using DHT in the detection of circulating tumor cells (CTCs).
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10
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Kou Y, Geng F, Guo D. Lipid Metabolism in Glioblastoma: From De Novo Synthesis to Storage. Biomedicines 2022; 10:1943. [PMID: 36009491 PMCID: PMC9405736 DOI: 10.3390/biomedicines10081943] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/01/2022] [Accepted: 08/06/2022] [Indexed: 12/12/2022] Open
Abstract
Glioblastoma (GBM) is the most lethal primary brain tumor. With limited therapeutic options, novel therapies are desperately needed. Recent studies have shown that GBM acquires large amounts of lipids for rapid growth through activation of sterol regulatory element-binding protein 1 (SREBP-1), a master transcription factor that regulates fatty acid and cholesterol synthesis, and cholesterol uptake. Interestingly, GBM cells divert substantial quantities of lipids into lipid droplets (LDs), a specific storage organelle for neutral lipids, to prevent lipotoxicity by increasing the expression of diacylglycerol acyltransferase 1 (DGAT1) and sterol-O-acyltransferase 1 (SOAT1), which convert excess fatty acids and cholesterol to triacylglycerol and cholesteryl esters, respectively. In this review, we will summarize recent progress on our understanding of lipid metabolism regulation in GBM to promote tumor growth and discuss novel strategies to specifically induce lipotoxicity to tumor cells through disrupting lipid storage, a promising new avenue for treating GBM.
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Affiliation(s)
- Yongjun Kou
- Department of Radiation Oncology, Ohio State Comprehensive Cancer Center, Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, College of Medicine at The Ohio State University, Columbus, OH 43012, USA
| | - Feng Geng
- Department of Radiation Oncology, Ohio State Comprehensive Cancer Center, Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, College of Medicine at The Ohio State University, Columbus, OH 43012, USA
| | - Deliang Guo
- Department of Radiation Oncology, Ohio State Comprehensive Cancer Center, Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, College of Medicine at The Ohio State University, Columbus, OH 43012, USA
- Center for Cancer Metabolism, James Comprehensive Cancer Center at The Ohio State University, Columbus, OH 43210, USA
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11
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Liang H, Yan J, Song K. Comprehensive lipidomic analysis reveals regulation of glyceride metabolism in rat visceral adipose tissue by high-altitude chronic hypoxia. PLoS One 2022; 17:e0267513. [PMID: 35522648 PMCID: PMC9075645 DOI: 10.1371/journal.pone.0267513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 04/10/2022] [Indexed: 11/18/2022] Open
Abstract
Adipose tissue plays a central role in energy substrate homeostasis and is a key regulator of lipid flow throughout these processes. As hypoxia affects lipid metabolism in adipose tissue, we aimed to investigate the effects of high-altitude chronic hypoxia on lipid metabolism in the adipose tissue of rats using a lipidomic analysis approach. Visceral adipose tissues from rats housed in a high-altitude hypoxia environment representing 4,300 m with 14.07% oxygen (hypoxia group) and from rats housed in a low-altitude normoxia environment representing 41 m with 20.95% oxygen (normoxia group) for 8 weeks were analyzed using an ultra-performance liquid chromatography-Orbitrap mass spectrometry system. After 8 weeks, the body weight and visceral adipose tissue weight of the hypoxia group were significantly decreased compared to those of the normoxia group (p < 0.05). The area and diameter of visceral adipose cells in the hypoxia group were significantly smaller than those of visceral adipose cells in the normoxia group (p < 0.05). The results of lipidomic analysis showed a total of 21 lipid classes and 819 lipid species. The total lipid concentration of the hypoxia group was lower than that in the normoxia group (p < 0.05). Concentrations of diacylglycerols and triacylglycerols in the hypoxia group were significantly lower than those in the normoxia group (p < 0.05). Using univariate and multivariate analyses, we identified 74 lipids that were significantly altered between the normoxia and hypoxia groups. These results demonstrate that high-altitude chronic hypoxia changes the metabolism of visceral adipose glycerides, which may potentially modulate other metabolic processes.
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Affiliation(s)
- Hong Liang
- Department of Basic Medical Sciences, Medical College, Qinghai University, Xining, PR, China
| | - Jun Yan
- Cardiovascular Medicine Department, Xuzhou Medical University affiliated Hospital, Xuzhou, PR China
| | - Kang Song
- Endocrinology Department, Qinghai Provincial People’s Hospital, Xining, PR, China
- Qinghai University affiliated Provincial People’s Hospital, Xining, PR, China
- * E-mail:
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12
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Islimye E, Girard V, Gould AP. Functions of Stress-Induced Lipid Droplets in the Nervous System. Front Cell Dev Biol 2022; 10:863907. [PMID: 35493070 PMCID: PMC9047859 DOI: 10.3389/fcell.2022.863907] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 03/22/2022] [Indexed: 12/12/2022] Open
Abstract
Lipid droplets are highly dynamic intracellular organelles that store neutral lipids such as cholesteryl esters and triacylglycerols. They have recently emerged as key stress response components in many different cell types. Lipid droplets in the nervous system are mostly observed in vivo in glia, ependymal cells and microglia. They tend to become more numerous in these cell types and can also form in neurons as a consequence of ageing or stresses involving redox imbalance and lipotoxicity. Abundant lipid droplets are also a characteristic feature of several neurodegenerative diseases. In this minireview, we take a cell-type perspective on recent advances in our understanding of lipid droplet metabolism in glia, neurons and neural stem cells during health and disease. We highlight that a given lipid droplet subfunction, such as triacylglycerol lipolysis, can be physiologically beneficial or harmful to the functions of the nervous system depending upon cellular context. The mechanistic understanding of context-dependent lipid droplet functions in the nervous system is progressing apace, aided by new technologies for probing the lipid droplet proteome and lipidome with single-cell type precision.
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Li Y, Li Z, Ngandiri DA, Llerins Perez M, Wolf A, Wang Y. The Molecular Brakes of Adipose Tissue Lipolysis. Front Physiol 2022; 13:826314. [PMID: 35283787 PMCID: PMC8907745 DOI: 10.3389/fphys.2022.826314] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/10/2022] [Indexed: 12/11/2022] Open
Abstract
Adaptation to changes in energy availability is pivotal for the survival of animals. Adipose tissue, the body’s largest reservoir of energy and a major source of metabolic fuel, exerts a buffering function for fluctuations in nutrient availability. This functional plasticity ranges from energy storage in the form of triglycerides during periods of excess energy intake to energy mobilization via lipolysis in the form of free fatty acids for other organs during states of energy demands. The subtle balance between energy storage and mobilization is important for whole-body energy homeostasis; its disruption has been implicated as contributing to the development of insulin resistance, type 2 diabetes and cancer cachexia. As a result, adipocyte lipolysis is tightly regulated by complex regulatory mechanisms involving lipases and hormonal and biochemical signals that have opposing effects. In thermogenic brown and brite adipocytes, lipolysis stimulation is the canonical way for the activation of non-shivering thermogenesis. Lipolysis proceeds in an orderly and delicately regulated manner, with stimulation through cell-surface receptors via neurotransmitters, hormones, and autocrine/paracrine factors that activate various intracellular signal transduction pathways and increase kinase activity. The subsequent phosphorylation of perilipins, lipases, and cofactors initiates the translocation of key lipases from the cytoplasm to lipid droplets and enables protein-protein interactions to assemble the lipolytic machinery on the scaffolding perilipins at the surface of lipid droplets. Although activation of lipolysis has been well studied, the feedback fine-tuning is less well appreciated. This review focuses on the molecular brakes of lipolysis and discusses some of the divergent fine-tuning strategies in the negative feedback regulation of lipolysis, including delicate negative feedback loops, intermediary lipid metabolites-mediated allosteric regulation and dynamic protein–protein interactions. As aberrant adipocyte lipolysis is involved in various metabolic diseases and releasing the brakes on lipolysis in thermogenic adipocytes may activate thermogenesis, targeting adipocyte lipolysis is thus of therapeutic interest.
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14
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Huang W, Gao F, Zhang Y, Chen T, Xu C. Lipid Droplet-Associated Proteins in Cardiomyopathy. ANNALS OF NUTRITION AND METABOLISM 2021; 78:1-13. [PMID: 34856540 DOI: 10.1159/000520122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 10/08/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND The heart requires a high rate of fatty-acid oxidation (FAO) to meet its energy needs. Neutral lipids are the main source of energy for the heart and are stored in lipid droplets (LDs), which are cytosolic organelles that primarily serve to store neutral lipids and regulate cellular lipid metabolism. LD-associated proteins (LDAPs) are proteins either located on the surface of the LDs or reside in the cytosol and contribute to lipid metabolism. Therefore, abnormal cardiac lipid accumulation or FAO can alter the redox state of the heart, resulting in cardiomyopathy, a group of diseases that negatively affect the myocardial function, thereby leading to heart failure and even cardiac death. SUMMARY LDs, along with LDAPs, are pivotal for modulating heart lipid homeostasis. The proper cardiac development and the maintenance of its normal function depend largely on lipid homeostasis regulated by LDs and LDAPs. Overexpression or deletion of specific LDAPs can trigger myocardial dysfunction and may contribute to the development of cardiomyopathy. Extensive connections and interactions may also exist between LDAPs. Key Message: In this review, the various mechanisms involved in LDAP-mediated regulation of lipid metabolism, the association between cardiac development and lipid metabolism, as well as the role of LDAPs in cardiomyopathy progression are discussed.
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Affiliation(s)
- Weiwei Huang
- Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China.,Department of Physiology and Pathophysiology, State Key Laboratory of Medical Neurobiology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Fei Gao
- Department of Physiology and Pathophysiology, State Key Laboratory of Medical Neurobiology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Yuting Zhang
- Department of Physiology and Pathophysiology, State Key Laboratory of Medical Neurobiology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Tianhui Chen
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital of Fudan University, Shanghai, China.,Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Chen Xu
- Department of Physiology and Pathophysiology, State Key Laboratory of Medical Neurobiology, School of Basic Medical Sciences, Fudan University, Shanghai, China
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15
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Grabner GF, Xie H, Schweiger M, Zechner R. Lipolysis: cellular mechanisms for lipid mobilization from fat stores. Nat Metab 2021; 3:1445-1465. [PMID: 34799702 DOI: 10.1038/s42255-021-00493-6] [Citation(s) in RCA: 204] [Impact Index Per Article: 68.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 10/15/2021] [Indexed: 12/13/2022]
Abstract
The perception that intracellular lipolysis is a straightforward process that releases fatty acids from fat stores in adipose tissue to generate energy has experienced major revisions over the last two decades. The discovery of new lipolytic enzymes and coregulators, the demonstration that lipophagy and lysosomal lipolysis contribute to the degradation of cellular lipid stores and the characterization of numerous factors and signalling pathways that regulate lipid hydrolysis on transcriptional and post-transcriptional levels have revolutionized our understanding of lipolysis. In this review, we focus on the mechanisms that facilitate intracellular fatty-acid mobilization, drawing on canonical and noncanonical enzymatic pathways. We summarize how intracellular lipolysis affects lipid-mediated signalling, metabolic regulation and energy homeostasis in multiple organs. Finally, we examine how these processes affect pathogenesis and how lipolysis may be targeted to potentially prevent or treat various diseases.
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Affiliation(s)
- Gernot F Grabner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Hao Xie
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Martina Schweiger
- Institute of Molecular Biosciences, University of Graz, Graz, Austria.
- BioTechMed-Graz, Graz, Austria.
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria.
- BioTechMed-Graz, Graz, Austria.
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16
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Lee SH, Golinska M, Griffiths JR. HIF-1-Independent Mechanisms Regulating Metabolic Adaptation in Hypoxic Cancer Cells. Cells 2021; 10:2371. [PMID: 34572020 PMCID: PMC8472468 DOI: 10.3390/cells10092371] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/31/2021] [Accepted: 09/02/2021] [Indexed: 12/22/2022] Open
Abstract
In solid tumours, cancer cells exist within hypoxic microenvironments, and their metabolic adaptation to this hypoxia is driven by HIF-1 transcription factor, which is overexpressed in a broad range of human cancers. HIF inhibitors are under pre-clinical investigation and clinical trials, but there is evidence that hypoxic cancer cells can adapt metabolically to HIF-1 inhibition, which would provide a potential route for drug resistance. Here, we review accumulating evidence of such adaptions in carbohydrate and creatine metabolism and other HIF-1-independent mechanisms that might allow cancers to survive hypoxia despite anti-HIF-1 therapy. These include pathways in glucose, glutamine, and lipid metabolism; epigenetic mechanisms; post-translational protein modifications; spatial reorganization of enzymes; signalling pathways such as Myc, PI3K-Akt, 2-hyxdroxyglutarate and AMP-activated protein kinase (AMPK); and activation of the HIF-2 pathway. All of these should be investigated in future work on hypoxia bypass mechanisms in anti-HIF-1 cancer therapy. In principle, agents targeted toward HIF-1β rather than HIF-1α might be advantageous, as both HIF-1 and HIF-2 require HIF-1β for activation. However, HIF-1β is also the aryl hydrocarbon nuclear transporter (ARNT), which has functions in many tissues, so off-target effects should be expected. In general, cancer therapy by HIF inhibition will need careful attention to potential resistance mechanisms.
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Affiliation(s)
- Shen-Han Lee
- Department of Otorhinolaryngology, Hospital Sultanah Bahiyah, KM6 Jalan Langgar, Alor Setar 05460, Kedah, Malaysia
| | - Monika Golinska
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK; (M.G.); (J.R.G.)
- Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, UK
| | - John R. Griffiths
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK; (M.G.); (J.R.G.)
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Sunami Y, Rebelo A, Kleeff J. Lipid Droplet-Associated Factors, PNPLA3, TM6SF2, and HSD17B Proteins in Hepatopancreatobiliary Cancer. Cancers (Basel) 2021; 13:cancers13174391. [PMID: 34503201 PMCID: PMC8431307 DOI: 10.3390/cancers13174391] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/17/2021] [Accepted: 08/25/2021] [Indexed: 12/16/2022] Open
Abstract
Simple Summary Aberrant lipid synthesis and reprogrammed lipid metabolism are both associated with the development and progression of pancreatic and liver cancer. Most cells store fatty acids in the form of triacylglycerols in lipid droplets. Lipid droplets are intracellular organelles that not only store neutral lipids, but also play roles as molecular messengers and signaling factors. Some cancer cells accumulate massive amount of lipid droplets. Lipid droplets and lipid droplet-associated factors are further implicated to mediate proliferation, invasion, metastasis, as well as chemotherapy resistance in several types of cancer. This review dissected recent findings on the role of several lipid droplet-associated factors, patatin-like phospholipase domain-containing 3 (PNPLA3), Transmembrane 6 superfamily member 2 (TM6SF2), and 17β-hydroxysteroid dehydrogenase (HSD17B) 11 and 13 as well as their genetic variations in hepatopancreatobiliary diseases, especially cancer. Abstract Pancreatic and liver cancer are leading causes of cancer deaths, and by 2030, they are projected to become the second and the third deadliest cancer respectively. Cancer metabolism, especially lipid metabolism, plays an important role in progression and metastasis of many types of cancer, including pancreatic and liver cancer. Lipid droplets are intracellular organelles that store neutral lipids, but also act as molecular messengers, and signaling factors. It is becoming increasingly evident that alterations in the regulation of lipid droplets and their associated factors influence the risk of developing not only metabolic disease but also fibrosis and cancer. In the current review article, we summarized recent findings concerning the roles of lipid droplet-associated factors, patatin-like phospholipase domain-containing 3, Transmembrane 6 superfamily member 2, and 17β-hydroxysteroid dehydrogenase 11 and 13 as well as genetic variants in pancreatic and hepatic diseases. A better understanding of cancer type- and cell type-specific roles of lipid droplet-associated factors is important for establishing new therapeutic options in the future.
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18
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The Propensity of the Human Liver to Form Large Lipid Droplets Is Associated with PNPLA3 Polymorphism, Reduced INSIG1 and NPC1L1 Expression and Increased Fibrogenetic Capacity. Int J Mol Sci 2021; 22:ijms22116100. [PMID: 34198853 PMCID: PMC8200978 DOI: 10.3390/ijms22116100] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/28/2021] [Accepted: 06/03/2021] [Indexed: 12/12/2022] Open
Abstract
In nonalcoholic steatohepatitis animal models, an increased lipid droplet size in hepatocytes is associated with fibrogenesis. Hepatocytes with large droplet (Ld-MaS) or small droplet (Sd-MaS) macrovesicular steatosis may coexist in the human liver, but the factors associated with the predominance of one type over the other, including hepatic fibrogenic capacity, are unknown. In pre-ischemic liver biopsies from 225 consecutive liver transplant donors, we retrospectively counted hepatocytes with Ld-MaS and Sd-MaS and defined the predominant type of steatosis as involving ≥50% of steatotic hepatocytes. We analyzed a donor Patatin-like phospholipase domain-containing protein 3 (PNPLA3) rs738409 polymorphism, hepatic expression of proteins involved in lipid metabolism by RT-PCR, hepatic stellate cell (HSC) activation by α-SMA immunohistochemistry and, one year after transplantation, histological progression of fibrosis due to Hepatitis C Virus (HCV) recurrence. Seventy-four livers had no steatosis, and there were 98 and 53 with predominant Ld-MaS and Sd-MaS, respectively. In linear regression models, adjusted for many donor variables, the percentage of steatotic hepatocytes affected by Ld-MaS was inversely associated with hepatic expression of Insulin Induced Gene 1 (INSIG-1) and Niemann-Pick C1-Like 1 gene (NPC1L1) and directly with donor PNPLA3 variant M, HSC activation and progression of post-transplant fibrosis. In humans, Ld-MaS formation by hepatocytes is associated with abnormal PNPLA3-mediated lipolysis, downregulation of both the intracellular cholesterol sensor and cholesterol reabsorption from bile and increased hepatic fibrogenesis.
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Bai R, Rebelo A, Kleeff J, Sunami Y. Identification of prognostic lipid droplet-associated genes in pancreatic cancer patients via bioinformatics analysis. Lipids Health Dis 2021; 20:58. [PMID: 34078402 PMCID: PMC8171034 DOI: 10.1186/s12944-021-01476-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 04/27/2021] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Pancreatic cancer is the fourth leading cause of cancer deaths in the United States both in females and in males, and is projected to become the second deadliest cancer by 2030. The overall 5-year survival rate remains at around 10%. Cancer metabolism and specifically lipid metabolism plays an important role in pancreatic cancer progression and metastasis. Lipid droplets can not only store and transfer lipids, but also act as molecular messengers, and signaling factors. As lipid droplets are implicated in reprogramming tumor cell metabolism and in invasion and migration of pancreatic cancer cells, we aimed to identify lipid droplet-associated genes as prognostic markers in pancreatic cancer. METHODS We performed a literature search on review articles related to lipid droplet-associated proteins. To select relevant lipid droplet-associated factors, bioinformatics analysis on the GEPIA platform (data are publicly available) was carried out for selected genes to identify differential expression in pancreatic cancer versus healthy pancreatic tissues. Differentially expressed genes were further analyzed regarding overall survival of pancreatic cancer patients. RESULTS 65 factors were identified as lipid droplet-associated factors. Bioinformatics analysis of 179 pancreatic cancer samples and 171 normal pancreatic tissue samples on the GEPIA platform identified 39 deferentially expressed genes in pancreatic cancer with 36 up-regulated genes (ACSL3, ACSL4, AGPAT2, BSCL2, CAV1, CAV2, CAVIN1, CES1, CIDEC, DGAT1, DGAT2, FAF2, G0S2, HILPDA, HSD17B11, ICE2, LDAH, LIPE, LPCAT1, LPCAT2, LPIN1, MGLL, NAPA, NCEH1, PCYT1A, PLIN2, PLIN3, RAB5A, RAB7A, RAB8A, RAB18, SNAP23, SQLE, VAPA, VCP, VMP1) and 3 down-regulated genes (FITM1, PLIN4, PLIN5). Among 39 differentially expressed factors, seven up-regulated genes (CAV2, CIDEC, HILPDA, HSD17B11, NCEH1, RAB5A, and SQLE) and two down-regulation genes (BSCL2 and FITM1) were significantly associated with overall survival of pancreatic cancer patients. Multivariate Cox regression analysis identified CAV2 as the only independent prognostic factor. CONCLUSIONS Through bioinformatics analysis, we identified nine prognostic relevant differentially expressed genes highlighting the role of lipid droplet-associated factors in pancreatic cancer.
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Affiliation(s)
- Rubing Bai
- Department of Visceral, Vascular and Endocrine Surgery, University Medical Center, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Strasse 40, 06120, Halle (Saale), Germany
| | - Artur Rebelo
- Department of Visceral, Vascular and Endocrine Surgery, University Medical Center, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Strasse 40, 06120, Halle (Saale), Germany
| | - Jörg Kleeff
- Department of Visceral, Vascular and Endocrine Surgery, University Medical Center, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Strasse 40, 06120, Halle (Saale), Germany
| | - Yoshiaki Sunami
- Department of Visceral, Vascular and Endocrine Surgery, University Medical Center, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Strasse 40, 06120, Halle (Saale), Germany.
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20
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Sheng Y, Li J, Yang Y, Lu Y. Hypoxia-inducible lipid droplet-associated (HILPDA) facilitates the malignant phenotype of lung adenocarcinoma cells in vitro through modulating cell cycle pathways. Tissue Cell 2021; 70:101495. [PMID: 33535136 DOI: 10.1016/j.tice.2021.101495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 12/10/2020] [Accepted: 01/11/2021] [Indexed: 12/31/2022]
Abstract
BACKGROUND Hypoxia-inducible lipid droplet-associated (HILPDA) is considered to have tumorigenic activity, but its function in lung adenocarcinoma (LUAD) is rarely known. This work aimed to assess the regulatory functions as well as the in-depth mechanism of HILPDA in LUAD. METHODS The expression of HILPDA in LUAD tissues was analyzed based on TCGA database, and then qRT-PCR was performed to confirm the HILPDA expression in LUAD cell lines. Kaplan-Meier analysis was used to measure the correlation of HILPDA expression and overall survival in patients with LUAD. Then, Cell-Counting Kit-8 (CCK-8), colony formation and transwell assays were performed to detect cell proliferation, invasion and migration. Moreover, the pathways closely related to the high HILPDA expression was analyzed by Kyoto Encyclopedia of genes and Genomes (KEGG) analysis. The levels of Cell cycle pathway-related proteins were assessed using western blotting. RESULTS Herein, we revealed that HILPDA was expressed at high levels in LUAD tissues and cell lines, and LUAD patients with the higher HILPDA expression presented the shorter survival time. Down-regulation of HILPDA in Calu-3 cells can retard cell proliferation, migration and invasion as well as arrest cells in the G1 phase, whereas overexpression of HILPDA in A549 cells presented a marked promotion on these phenotypes. Moreover, we surveyed that knockdown of HILPDA restrained the activation of cell cycle pathway, while up-regulation of HILPDA led to opponent outcomes. CONCLUSIONS In summing, HILPDA may act as an oncogenic factor in LUAD cells via modulating cell cycle pathway, which represent a novel biomarker of tumorigenesis in LUAD patients.
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Affiliation(s)
- Yanrui Sheng
- Department of Clinical Laboratory, Jining No.1 People's Hospital, Jining, PR China
| | - Jinlong Li
- Department of Respiratory Medicine, Suixi County Hospital, Huaibei, PR China
| | - Yanna Yang
- Department of Respiratory and Critical Care Medicine, Central Hospital Affiliated to Shandong First Medical University, Jinan, PR China
| | - Yingyun Lu
- Department of Rehabilitation Medicine, Shandong Provincial Third Hospital, Cheeloo College of Medicine, Shandong University, Jinan, PR China.
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Povero D, Johnson SM, Liu J. Hypoxia, hypoxia-inducible gene 2 (HIG2)/HILPDA, and intracellular lipolysis in cancer. Cancer Lett 2020; 493:71-79. [PMID: 32818550 PMCID: PMC11218043 DOI: 10.1016/j.canlet.2020.06.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 05/27/2020] [Accepted: 06/13/2020] [Indexed: 12/16/2022]
Abstract
Tumor tissues are chronically exposed to hypoxia owing to aberrant vascularity. Hypoxia induces metabolic alterations in cancer, thereby promoting aggressive malignancy and metastasis. While previous efforts largely focused on adaptive responses in glucose and glutamine metabolism, recent studies have begun to yield important insight into the hypoxic regulation of lipid metabolic reprogramming in cancer. Emerging evidence points to lipid droplet (LD) accumulation as a hallmark of hypoxic cancer cells. One critical underlying mechanism involves the inhibition of adipose triglyceride lipase (ATGL)-mediated intracellular lipolysis by a small protein encoded by hypoxia-inducible gene 2 (HIG2), also known as hypoxia inducible lipid droplet associated (HILPDA). In this review we summarize and discuss recent key findings on hypoxia-dependent regulation of metabolic adaptations especially lipolysis in cancer. We also pose several questions and hypotheses pertaining to the metabolic impact of lipolytic regulation in cancer under hypoxia and during hypoxia-reoxygenation transition.
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Affiliation(s)
- Davide Povero
- From Department of Biochemistry and Molecular Biology, Rochester, MN, 55905, USA; Division of Endocrinology, Rochester, MN, 55905, USA
| | - Scott M Johnson
- From Department of Biochemistry and Molecular Biology, Rochester, MN, 55905, USA; Mayo Clinic College of Medicine & Science, Rochester, MN, 55905, USA; Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, 55905, USA
| | - Jun Liu
- From Department of Biochemistry and Molecular Biology, Rochester, MN, 55905, USA; Division of Endocrinology, Rochester, MN, 55905, USA.
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