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Viegas J. Profile of Jonathan C. Cohen. Proc Natl Acad Sci U S A 2024; 121:e2410922121. [PMID: 38913895 DOI: 10.1073/pnas.2410922121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/26/2024] Open
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2
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Nagai TH, Mizoguchi T, Wang Y, Deik A, Bullock K, Clish CB, Xu YX. ANGPTL3 regulates the peroxisomal translocation of SmarcAL1 in response to cell growth states. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.03.597253. [PMID: 38895318 PMCID: PMC11185727 DOI: 10.1101/2024.06.03.597253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Angiopoietin-like 3 (ANGPTL3) is a key regulator of lipoprotein metabolism, known for its potent inhibition on intravascular lipoprotein and endothelial lipase activities. Recent studies have shed light on the cellular functions of ANGPTL3. However, the precise mechanism underlying its regulation of cellular lipid metabolism remains elusive. We recently reported that ANGPTL3 interacts with the chromatin regulator SMARCAL1, which plays a pivotal role in maintaining cellular lipid homeostasis. Here, through a combination of in vitro and in vivo functional analyses, we provide evidence that ANGPTL3 indeed influences cellular lipid metabolism. Increased expression of Angptl3 prompted the formation of lipid droplets (LDs) in response to slow growth conditions. Notably, under the conditions, Angptl3 accumulated within cytoplasmic peroxisomes, where it interacts with SmarcAL1, which translocated from nucleus as observed previously. This translocation induced changes in gene expression favoring triglyceride (TG) accumulation. Indeed, ANGPTL3 gene knockout (KO) in human cells increased the expression of key lipid genes, which could be linked to elevated nuclear localization of SMARCAL1, whereas the expression of these genes decreased in SMARCAL1 KO cells. Consistent with these findings, the injection of Angptl3 protein to mice led to hepatic fat accumulation derived from circulating blood, a phenotype likely indicative of its long-term effect on blood TG, linked to SmarcAL1 activities. Thus, our results suggest that the Angptl3-SmarcAL1 pathway may confer the capacity for TG storage in cells in response to varying growth states, which may have broad implications for this pathway in regulating energy storage and trafficking.
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Keshvari S, Masson JJR, Ferrari-Cestari M, Bodea LG, Nooru-Mohamed F, Tse BWC, Sokolowski KA, Batoon L, Patkar OL, Sullivan MA, Ebersbach H, Stutz C, Parton RG, Summers KM, Pettit AR, Hume DA, Irvine KM. Reversible expansion of tissue macrophages in response to macrophage colony-stimulating factor (CSF1) transforms systemic lipid and carbohydrate metabolism. Am J Physiol Endocrinol Metab 2024; 326:E149-E165. [PMID: 38117267 DOI: 10.1152/ajpendo.00347.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 12/01/2023] [Accepted: 12/17/2023] [Indexed: 12/21/2023]
Abstract
Macrophages regulate metabolic homeostasis in health and disease. Macrophage colony-stimulating factor (CSF1)-dependent macrophages contribute to homeostatic control of the size of the liver. This study aimed to determine the systemic metabolic consequences of elevating circulating CSF1. Acute administration of a CSF1-Fc fusion protein to mice led to monocytosis, increased resident tissue macrophages in the liver and all major organs, and liver growth. These effects were associated with increased hepatic glucose uptake and extensive mobilization of body fat. The impacts of CSF1 on macrophage abundance, liver size, and body composition were rapidly reversed to restore homeostasis. The effects of CSF1 on metabolism were independent of several known endocrine regulators and did not impact the physiological fasting response. Analysis using implantable telemetry in metabolic cages revealed progressively reduced body temperature and physical activity with no change in diurnal food intake. These results demonstrate the existence of a dynamic equilibrium between CSF1, the mononuclear phagocyte system, and control of liver-to-body weight ratio, which in turn controls systemic metabolic homeostasis. This novel macrophage regulatory axis has the potential to promote fat mobilization, without changes in appetence, which may have novel implications for managing metabolic syndrome.NEW & NOTEWORTHY CSF1 administration expands tissue macrophages, which transforms systemic metabolism. CSF1 drives fat mobilization and glucose uptake to support liver growth. The effects of CSF1 are independent of normal hormonal metabolic regulation. The effects of CSF1 are rapidly reversible, restoring homeostatic body composition. CSF1-dependent macrophages and liver size are coupled in a dynamic equilibrium.
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Affiliation(s)
- Sahar Keshvari
- Mater Research Institute-The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Jesse J R Masson
- Mater Research Institute-The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Michelle Ferrari-Cestari
- Mater Research Institute-The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Liviu-Gabriel Bodea
- Clem Jones Centre for Ageing and Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Fathima Nooru-Mohamed
- Mater Research Institute-The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Brian W C Tse
- Preclinical Imaging Facility, Translational Research Institute, Brisbane, Queensland, Australia
| | - Kamil A Sokolowski
- Preclinical Imaging Facility, Translational Research Institute, Brisbane, Queensland, Australia
| | - Lena Batoon
- Mater Research Institute-The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Omkar L Patkar
- Mater Research Institute-The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Mitchell A Sullivan
- Mater Research Institute-The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Hilmar Ebersbach
- Novartis Institutes for Biomedical Research (NIBR), Basel, Switzerland
| | - Cian Stutz
- Novartis Institutes for Biomedical Research (NIBR), Basel, Switzerland
| | - Robert G Parton
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
- Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland, Australia
| | - Kim M Summers
- Mater Research Institute-The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Allison R Pettit
- Mater Research Institute-The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - David A Hume
- Mater Research Institute-The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Katharine M Irvine
- Mater Research Institute-The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
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Nagai TH, Hartigan C, Mizoguchi T, Yu H, Deik A, Bullock K, Wang Y, Cromley D, Schenone M, Cowan CA, Rader DJ, Clish CB, Carr SA, Xu YX. Chromatin regulator SMARCAL1 modulates cellular lipid metabolism. Commun Biol 2023; 6:1298. [PMID: 38129665 PMCID: PMC10739977 DOI: 10.1038/s42003-023-05665-6] [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: 05/25/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023] Open
Abstract
Biallelic mutations of the chromatin regulator SMARCAL1 cause Schimke Immunoosseous Dysplasia (SIOD), characterized by severe growth defects and premature mortality. Atherosclerosis and hyperlipidemia are common among SIOD patients, yet their onset and progression are poorly understood. Using an integrative approach involving proteomics, mouse models, and population genetics, we investigated SMARCAL1's role. We found that SmarcAL1 interacts with angiopoietin-like 3 (Angptl3), a key regulator of lipoprotein metabolism. In vitro and in vivo analyses demonstrate SmarcAL1's vital role in maintaining cellular lipid homeostasis. The observed translocation of SmarcAL1 to cytoplasmic peroxisomes suggests a potential regulatory role in lipid metabolism through gene expression. SmarcAL1 gene inactivation reduces the expression of key genes in cellular lipid catabolism. Population genetics investigations highlight significant associations between SMARCAL1 genetic variations and body mass index, along with lipid-related traits. This study underscores SMARCAL1's pivotal role in cellular lipid metabolism, likely contributing to the observed lipid phenotypes in SIOD patients.
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Affiliation(s)
- Taylor Hanta Nagai
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, 02114, USA
| | | | - Taiji Mizoguchi
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Haojie Yu
- Division of Cardiovascular Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Amy Deik
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Kevin Bullock
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Yanyan Wang
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Debra Cromley
- Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Monica Schenone
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Chad A Cowan
- Division of Cardiovascular Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Daniel J Rader
- Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Clary B Clish
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Steven A Carr
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Yu-Xin Xu
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, 02114, USA.
- Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA.
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Chen YQ, Zhen EY, Russell AM, Ehsani M, Siegel RW, Qian Y, Konrad RJ. Decoding the role of angiopoietin-like protein 4/8 complex-mediated plasmin generation in the regulation of LPL activity. J Lipid Res 2023; 64:100441. [PMID: 37666362 PMCID: PMC10550811 DOI: 10.1016/j.jlr.2023.100441] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 08/17/2023] [Accepted: 08/28/2023] [Indexed: 09/06/2023] Open
Abstract
After feeding, adipose tissue lipoprotein lipase (LPL) activity should be maximized, therefore the potent LPL-inhibitory activity of angiopoietin-like protein 4 (ANGPTL4) must be blocked by ANGPTL8 through formation of ANGPTL4/8 complexes. ANGPTL4/8 tightly binds and protects LPL but also partially inhibits its activity. Recently, we demonstrated ANGPTL4/8 also binds tissue plasminogen activator (tPA) and plasminogen to generate plasmin that cleaves ANGPTL4/8 to restore LPL activity. Although fully active LPL in the fat postprandially is desirable, ANGPTL4/8 removal could subject LPL to profound inhibition by ANGPTL3/8 (the most potent circulating LPL inhibitor), inhibition by other LPL inhibitors like ANGPTL4, ANGPTL3, and ApoC3 or interfere with ApoC2-mediated LPL activation. To understand better these potential paradoxes, we examined LPL inhibition by ANGPTL3/8, ANGPTL4, ANGPTL3, and ApoC3 and LPL stimulation by ApoC2 in the presence of ANGPTL4/8 + tPA + plasminogen. Remarkably, ANGPTL3/8-mediated LPL inhibition was almost completely blocked, with the mechanism being cleavage of fibrinogen-like domain-containing ANGPTL3 present in the ANGPTL3/8 complex. The LPL-inhibitory effects of ANGPTL4, ANGPTL3, and ApoC3 were also largely reduced in the presence of ANGPTL4/8 + tPA + plasminogen. In contrast, the ability of ApoC2 to stimulate LPL activity was unaffected by ANGPTL4/8-mediated plasmin generation. Together, these results explain how plasmin generated by increased postprandial ANGPTL4/8 levels in adipose tissue enables maximal LPL activity by preventing ANGPTL3/8, ANGPTL4, ANGPTL3, and ApoC3 from inhibiting LPL, while permitting ApoC2-mediated LPL activation to occur.
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Affiliation(s)
- Yan Q Chen
- Lilly Research Laboratories, Eli Lilly, and Company, Indianapolis, IN, USA
| | - Eugene Y Zhen
- Lilly Research Laboratories, Eli Lilly, and Company, Indianapolis, IN, USA
| | - Anna M Russell
- Lilly Research Laboratories, Eli Lilly, and Company, Indianapolis, IN, USA
| | - Mariam Ehsani
- Lilly Research Laboratories, Eli Lilly, and Company, Indianapolis, IN, USA
| | - Robert W Siegel
- Lilly Research Laboratories, Eli Lilly, and Company, Indianapolis, IN, USA
| | - Yuewei Qian
- Lilly Research Laboratories, Eli Lilly, and Company, Indianapolis, IN, USA
| | - Robert J Konrad
- Lilly Research Laboratories, Eli Lilly, and Company, Indianapolis, IN, USA.
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How ANGPTL3 Inhibition Will Help Our Clinical Practice? Curr Atheroscler Rep 2023; 25:19-29. [PMID: 36607583 DOI: 10.1007/s11883-022-01076-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2022] [Indexed: 01/07/2023]
Abstract
PURPOSE OF REVIEW This review aims to summarize the most recently published literature highlighting the potential of pharmacological inhibition of ANGPTL3 in treating patients suffering from dyslipidemias. The rational for this strategy will be discussed considering evidence describing the role of ANGPTL3 in lipid metabolism and the consequences of its deficiency in humans. RECENT FINDINGS Recent trials have demonstrated the efficacy and safety of ANGPTL3 inhibition in treating homozygous familial hypercholesterolemia even in those patients carrying biallelic null/null variants, thus supporting the notion that the LDL-lowering effect of ANGPLT3 inhibition is LDLR-independent. The use of ANGPTL3 inhibition strategies has expanded its indications in hypertrygliceridemic patients with functional lipoprotein lipase activity. Contemporarily, the pharmacological research is exploring novel approaches to ANGPTL3 inhibition such as the use of a small interfering RNA targeting the ANGPTL3 transcript in the liver, a protein-based vaccine against ANGPTL3, and a CRISP-Cas-9 method for a liver-selective knock-out of ANGPTL3 gene. First, we will describe the molecular function of ANGPTL3 in lipoprotein metabolism. Then, we will revise the clinical characteristics of individuals carrying loss-of-function mutations of ANGPTL3, a rare condition known as familial hypobetalipoproteinemia type 2 (FHBL2) that represents a unique human model of ANGPTL3 deficiency. Finally, we will examine the lipid-lowering potential of pharmacological inhibition of ANGPTL3 based on the results of clinical trials employing Evinacumab, the first approved fully humanized monoclonal antibody against ANGPTL3. The future perspectives for ANGPTL3 inhibition will also be revised.
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Lv Q, Han X, Ni J, Ma Q, Dai R, Liu J, Liu J, Zhai Y, Shen Q, Sun L, Liu H, Rao J, Xu H. Anti-ANGPTL3-FLD monoclonal antibody treatment ameliorates podocyte lesions through attenuating mitochondrial damage. Cell Death Dis 2022; 13:867. [PMID: 36229446 PMCID: PMC9562403 DOI: 10.1038/s41419-022-05313-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 09/27/2022] [Accepted: 09/29/2022] [Indexed: 11/06/2022]
Abstract
Proteinuria, an indication of kidney disease, is caused by the malfunction of podocytes, which play a key role in maintaining glomerular filtration. Angiopoietin-like 3 (ANGPTL3) has been documented to have a cell-autonomous involvement in podocytes, and deletion of Angptl3 in podocytes reduced proteinuria in adriamycin-induced nephropathy. Here, we developed a monoclonal antibody (mAb) against ANGPTL3 to investigate its effects on podocyte injury in an ADR nephropathy mouse model and puromycin (PAN) induced podocyte damage in vitro. The mAb against the human ANGPTL3-FLD sequence (5E5F6) inhibited the binding of ANGPTL3-FLD to integrin β3. Treatment with the 5E5F6 mAb in ADR nephropathy mice mitigated proteinuria and led to a significant decline in podocyte apoptosis, reactive oxygen species (ROS) generation and mitochondrial fragmentation. In PAN-induced podocyte damage in vitro, the 5E5F6 mAb blocked the ANPGPLT3-mediated activation of integrin αvβ3 and Rac1, which regulated the mitochondrial homeostasis. Altogether, anti-ANGPLT3-FLD mAb attenuates proteinuria and podocyte lesions in ADR mice models, as well as PAN-induced podocyte damage, in part through regulating mitochondrial functions. Our study provides a therapeutic approach for targeting ANGPTL3 in proteinuric kidney disease.
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Affiliation(s)
- Qianying Lv
- grid.411333.70000 0004 0407 2968Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China ,Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Xinli Han
- grid.411333.70000 0004 0407 2968Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China ,Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Jiajia Ni
- grid.411333.70000 0004 0407 2968Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China ,Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Qianqian Ma
- grid.411333.70000 0004 0407 2968Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China ,Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Rufeng Dai
- grid.411333.70000 0004 0407 2968Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China ,Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Jiaojiao Liu
- grid.411333.70000 0004 0407 2968Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China ,Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Jialu Liu
- grid.411333.70000 0004 0407 2968Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China ,Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Yihui Zhai
- grid.411333.70000 0004 0407 2968Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China ,Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Qian Shen
- grid.411333.70000 0004 0407 2968Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China ,Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Li Sun
- Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China ,grid.411333.70000 0004 0407 2968Department of Rheumatology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China
| | - Haimei Liu
- Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China ,grid.411333.70000 0004 0407 2968Department of Rheumatology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China
| | - Jia Rao
- grid.411333.70000 0004 0407 2968Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China ,Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Hong Xu
- grid.411333.70000 0004 0407 2968Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of CHINA, Shanghai, China ,Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
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Lv S, Zhou Y, Chen J, Yuan H, Zhang ZN, Luan B. Hepatic ER stress suppresses adipose browning through ATF4-CIRP-ANGPTL3 cascade. Cell Rep 2022; 40:111422. [PMID: 36170814 DOI: 10.1016/j.celrep.2022.111422] [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: 01/06/2022] [Revised: 07/28/2022] [Accepted: 09/07/2022] [Indexed: 12/01/2022] Open
Abstract
Hepatic endoplasmic reticulum (ER) stress is a hallmark of obesity-induced liver steatosis and contributes to the progress of steatosis and insulin resistance in liver. However, its influence on adipose function is still unclear. Here, we identify a hepatic ER stress-induced activating transcription factor 4 (ATF4)-cold-inducible RNA-binding protein (CIRP)-angiopoietin-related protein3 (ANGPTL3) cascade critical for the regulation of adipose browning. We find that obesity increases CIRP expression in liver through ER stress-induced ATF4. CIRP in turn binds to the 3' UTR and increases mRNA stability of ANGPTL3. ANGPTL3 secreted from liver suppresses uncoupling protein 1 expression through integrin αvβ3 and c-Jun N-terminal kinase in adipose tissue. While hepatic expression of either ATF4, CIRP, or ANGPTL3 suppresses adipose browning, knockdown of CIRP and ANGPTL3 in liver or administration of integrin αvβ3 inhibitor cilengitide increases adipose browning process. Taken together, we identify a communication mechanism to link hepatic ER stress and adipose browning that may imply a reciprocal regulation of obesity and liver steatosis.
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Affiliation(s)
- Sihan Lv
- Department of Endocrinology, Tongji Hospital Affiliated to Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
| | - Yingqun Zhou
- Department of Gastroenterology, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai 200072, China
| | - Jiaojiao Chen
- Department of Gastroenterology, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai 200072, China; School of Clinical Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Huiwen Yuan
- Department of Endocrinology, Tongji Hospital Affiliated to Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
| | - Zhen-Ning Zhang
- Translational Medical Center for Stem Cell Therapy & Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai 200120, China
| | - Bing Luan
- Department of Endocrinology, Tongji Hospital Affiliated to Tongji University, School of Medicine, Tongji University, Shanghai 200072, China.
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Jain R, Wade G, Ong I, Chaurasia B, Simcox J. Determination of tissue contributions to the circulating lipid pool in cold exposure via systematic assessment of lipid profiles. J Lipid Res 2022; 63:100197. [PMID: 35300982 PMCID: PMC9234243 DOI: 10.1016/j.jlr.2022.100197] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 02/21/2022] [Accepted: 02/27/2022] [Indexed: 01/07/2023] Open
Abstract
Plasma lipid levels are altered in chronic conditions such as type 2 diabetes and cardiovascular disease as well as during acute stresses such as fasting and cold exposure. Advances in MS-based lipidomics have uncovered a complex plasma lipidome of more than 500 lipids that serve functional roles, including as energy substrates and signaling molecules. This plasma lipid pool is maintained through regulation of tissue production, secretion, and uptake. A major challenge in understanding the lipidome complexity is establishing the tissues of origin and uptake for various plasma lipids, which is valuable for determining lipid functions. Using cold exposure as an acute stress, we performed global lipidomics on plasma and in nine tissues that may contribute to the circulating lipid pool. We found that numerous species of plasma acylcarnitines (ACars) and ceramides (Cers) were significantly altered upon cold exposure. Through computational assessment, we identified the liver and brown adipose tissue as major contributors and consumers of circulating ACars, in agreement with our previous work. We further identified the kidney and intestine as novel contributors to the circulating ACar pool and validated these findings with gene expression analysis. Regression analysis also identified that the brown adipose tissue and kidney are interactors with the plasma Cer pool. Taken together, these studies provide an adaptable computational tool to assess tissue contribution to the plasma lipid pool. Our findings have further implications in understanding the function of plasma ACars and Cers, which are elevated in metabolic diseases.
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Affiliation(s)
- Raghav Jain
- Department of Biochemistry, University of Wisconsin-Madison, Wisconsin, USA
| | - Gina Wade
- Department of Biochemistry, University of Wisconsin-Madison, Wisconsin, USA
| | - Irene Ong
- Department of Biostatistics and Medical Informatics, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Wisconsin, USA
| | - Bhagirath Chaurasia
- Division of Endocrinology, Department of Internal Medicine, Carver College of Medicine, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa, USA
| | - Judith Simcox
- Department of Biochemistry, University of Wisconsin-Madison, Wisconsin, USA.
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Bini S, Pecce V, Di Costanzo A, Polito L, Ghadiri A, Minicocci I, Tambaro F, Covino S, Arca M, D’Erasmo L. The Fibrinogen-like Domain of ANGPTL3 Facilitates Lipolysis in 3T3-L1 Cells by Activating the Intracellular Erk Pathway. Biomolecules 2022; 12:biom12040585. [PMID: 35454174 PMCID: PMC9028860 DOI: 10.3390/biom12040585] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 04/13/2022] [Accepted: 04/14/2022] [Indexed: 12/18/2022] Open
Abstract
Background: ANGPTL3 stimulates lipolysis in adipocytes, but the underlying molecular mechanism is yet unknown. The C-terminal fibrinogen-like domain of ANGPTL3 (ANGPTL3-Fld) activates the AKT pathway in endothelial cells. Hence, we evaluated whether ANGPTL3-Fld stimulates lipolysis in adipocytes through the MAPK kinase pathway. Materials and Methods: 3T3-L1 adipocytes were treated with isoproterenol (ISO), ANGPTL3-Fld, or both. Lipolysis was evaluated through the release of free fatty acids (FFAs) in the culture medium. The activation status of intracellular kinases was evaluated with and without the inhibition of the BRAF–ERK arm of the MAPK pathway. Results: ANGPTL3-Fld alone was not able to activate lipolysis, while the combination of ANGPTL3-Fld and ISO determined a 10-fold enrichment of the FFA concentration in the culture medium with an incremental effect (twofold) when compared with ISO alone. ANGPTL3-Fld alone inhibited hormone-sensitive lipase (HSL), whereas the treatment with ISO induced the activation of HSL. The net balance of ANGPTL3-Fld and ISO cotreatment resulted in HSL activation. The results indicate that ANGPTL3-Fld generated an intracellular activation signal involving the MAPK–ERK pathway, possibly through the PDGFRβ—PLCγ-AMPK axis. Conclusion: ANGPTL3-Fld appears to act as a facilitator of lipolysis in adipocytes, and this effect was driven by a signal mediated by a pathway that is different from the canonical β-adrenergic stimulus.
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11
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Zhong F, Liu S, Li Y, Li G, Liu M, Wang J, Cui W, Suo Y, Gao X. ANGPTL3 impacts proteinuria and hyperlipidemia in primary nephrotic syndrome. Lipids Health Dis 2022; 21:38. [PMID: 35399079 PMCID: PMC8996604 DOI: 10.1186/s12944-022-01632-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Accepted: 02/02/2022] [Indexed: 12/28/2022] Open
Abstract
Abstract
Background
It is unclear why primary nephrotic syndrome (PNS) patients often have dyslipidemia. Recent studies have shown that angiopoietin-like protein 3 (ANGPTL3) is an important regulator of lipid metabolism. In this study, we explored how ANGPTL3 impacts dyslipidemia during PNS development.
Methods
We measured the serum levels of ANGPTL3 in PNS patients (n=196). Furthermore, the degree of proteinuria and lipid metabolism were examined in angptl3-overexpressing transgenic (angptl3-tg) mice at different ages. Moreover, in this study, we used the clustered regularly interspaced short palindromic repeats-associated protein 9 (CRISPR/Cas9) system to create angptl3-knockout (angptl3-/-) mice to investigate lipopolysaccharide (LPS)-induced nephrosis.
Results
Compared with that in the healthy group, the serum level of ANGPTL3 in the PNS group was significantly increased (32 (26.35-39.66) ng/ml vs. 70.44 (63.95-76.51) ng/ml, Z =-4.81, P < 0.001). There were significant correlations between the serum level of ANGPTL3 and the levels of cholesterol (r=0.34, P < 0.001), triglycerides (r= 0.25, P = 0.001) and low-density lipoprotein (r= 0.50, P < 0.001) in PNS patients. With increasing age, angptl3-tg mice exhibited increasingly severe hypertriglyceridemia and proteinuria. The pathological features of angptl3-tg mice included rich lipid droplet deposition in hepatocytes and diffuse podocyte effacement. Compared to wild-type mice, angptl3-/- mice showed significantly lower degrees of lipid dysfunction and proteinuria after stimulation with LPS. The effects of ANGPTL3 on nephrotic dyslipidemia were confirmed in cultured hepatocytes subjected to angptl3 knockdown or overexpression. Finally, significant alterations in lipoprotein lipase (LPL) levels were observed in liver tissues from Angptl3-/- and wild-type mice stimulated with LPS.
Conclusions
ANGPTL3 could be involved in the development of dyslipidemia, as well as proteinuria, during PNS pathogenesis. Inhibition of LPL expression may the mechanism by which ANGPTL3 induces hyperlipidemia in PNS.
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12
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Abstract
PURPOSE OF REVIEW Over the last two decades, evolving discoveries around angiopoietin-like (ANGPTL) proteins, particularly ANGPTL3, ANGPTL4, and ANGPTL8, have generated significant interest in understanding their roles in fatty acid (FA) metabolism. Until recently, exactly how this protein family regulates lipoprotein lipase (LPL) in a tissue-specific manner to control FA partitioning has remained elusive. This review summarizes the latest insights into mechanisms by which ANGPTL3/4/8 proteins regulate postprandial FA partitioning. RECENT FINDINGS Accumulating evidence suggests that ANGPTL8 is an insulin-responsive protein that regulates ANGPTL3 and ANGPTL4 by forming complexes with them to increase or decrease markedly their respective LPL-inhibitory activities. After feeding, when insulin levels are high, ANGPTL3/8 secreted by hepatocytes acts in an endocrine manner to inhibit LPL in skeletal muscle, whereas ANGPTL4/8 secreted by adipocytes acts locally to preserve adipose tissue LPL activity, thus shifting FA toward the fat for storage. Insulin also decreases hepatic secretion of the endogenous ANGPTL3/8 inhibitor, apolipoprotein A5 (ApoA5), to accentuate ANGPTL3/8-mediated LPL inhibition in skeletal muscle. SUMMARY The ANGPTL3/4/8 protein family and ApoA5 play critical roles in directing FA toward adipose tissue postprandially. Selective targeting of these proteins holds significant promise for the treatment of dyslipidemias, metabolic syndrome, and their related comorbidities.
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Affiliation(s)
| | - Yan Q Chen
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana, USA
| | - Robert J Konrad
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana, USA
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13
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Zhang R, Zhang K. An updated ANGPTL3-4-8 model as a mechanism of triglyceride partitioning between fat and oxidative tissues. Prog Lipid Res 2022; 85:101140. [PMID: 34793860 PMCID: PMC8760165 DOI: 10.1016/j.plipres.2021.101140] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 01/03/2023]
Abstract
In mammals, triglyceride (TG), the main form of lipids for storing and providing energy, is stored in white adipose tissue (WAT) after food intake, while during fasting it is routed to oxidative tissues (heart and skeletal muscle) for energy production, a process referred to as TG partitioning. Lipoprotein lipase (LPL), a rate-limiting enzyme in this fundamental physiological process, hydrolyzes circulating TG to generate free fatty acids that are taken up by peripheral tissues. The postprandial activity of LPL declines in oxidative tissues but rises in WAT, directing TG to WAT; the reverse is true during fasting. However, the molecular mechanism in regulating tissue-specific LPL activity during the fed-fast cycle has not been completely understood. Research on angiopoietin-like (ANGPTL) proteins (A3, A4, and A8) has resulted in an ANGPTL3-4-8 model to explain the TG partitioning between WAT and oxidative tissues. Food intake induces A8 expression in the liver and WAT. Liver A8 activates A3 by forming the A3-8 complex, which is then secreted into the circulation. The A3-8 complex acts in an endocrine manner to inhibit LPL in oxidative tissues. WAT A8 forms the A4-8 complex, which acts locally to block A4's LPL-inhibiting activity. Therefore, the postprandial activity of LPL is low in oxidative tissues but high in WAT, directing circulating TG to WAT. Conversely, during fasting, reduced A8 expression in the liver and WAT disables A3 from inhibiting oxidative-tissue LPL and restores WAT A4's LPL-inhibiting activity, respectively. Thus, the fasting LPL activity is high in oxidative tissues but low in WAT, directing TG to the former. According to the model, we hypothesize that A8 antagonism has the potential to simultaneously reduce TG and increase HDL-cholesterol plasma levels. Future research on A3, A4, and A8 can hopefully provide more insights into human health, disease, and therapeutics.
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Affiliation(s)
- Ren Zhang
- Center for Molecular Medicine and Genetics, School of Medicine, Wayne State University, 540 East Canfield Street, Detroit, MI 48201, USA.
| | - Kezhong Zhang
- Center for Molecular Medicine and Genetics, School of Medicine, Wayne State University, 540 East Canfield Street, Detroit, MI 48201, USA
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14
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Zhao Z, Deng X, Jia J, Zhao L, Wang C, Cai Z, Guo C, Yang L, Wang D, Ma S, Deng J, Li H, Zhou L, Tu Z, Yuan G. Angiopoietin-like protein 8 (betatrophin) inhibits hepatic gluconeogenesis through PI3K/Akt signaling pathway in diabetic mice. Metabolism 2022; 126:154921. [PMID: 34715116 DOI: 10.1016/j.metabol.2021.154921] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 10/15/2021] [Accepted: 10/21/2021] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Angiopoietin-like protein 8 (ANGPTL8) is a 198 amino-acid long, novel secreted protein that is mainly expressed in the liver and brown adipose tissues. At present, evidence supporting the involvement of ANGPTL8 in the regulation of glucose metabolism is inconclusive, along with its function in the liver. Previous studies mainly focused on the effect of ANGPTL8 on glucose metabolism in non-diabetic mice, and few relevant studies in diabetic mice exist. Therefore, this study aimed to investigate the role of ANGPTL8 on glucose homeostasis and elucidate the underlying mechanisms in diabetic mice. METHODS db/db diabetic and high-fat diet/streptozotocin-induced diabetic mice were injected with adenovirus expressing ANGPTL8 through the tail vein. Blood glucose levels were measured and glucose, insulin, and pyruvate tolerance tests were performed. To explore the molecular mechanism by which ANGPTL8 regulates hepatic glucose metabolism and manipulate mouse ANGPTL8 expression levels both in vivo and in vitro based on adenoviral transduction, gain- and loss-of-function strategies were adopted. RESULTS Adenovirus-mediated overexpression of ANGPTL8 decreased fasting blood glucose levels and improved glucose tolerance and insulin sensitivity in db/db and high-fat diet/streptozotocin-induced diabetic mice. ANGPTL8 knockdown yielded the opposite effects. ANGPTL8 was upregulated in the cAMP/Dex-induced hepatocyte gluconeogenesis model. Moreover, ANGPTL8 overexpression in primary hepatocytes and diabetic mouse livers inhibited the expression of gluconeogenesis-related genes, including PEPCK and G6PC, by activating the AKT signaling pathway and, thereby, reducing glucose production. Therefore, the results demonstrated that ANGPTL8 improved glucose metabolism via inhibition of hepatic gluconeogenesis in diabetic mice. CONCLUSIONS Current findings highlight a critical role of hepatic ANGPTL8 in glucose homeostasis, suggesting that increased ANGPTL8 expression could be an underlying factor for the inhibition of hepatic gluconeogenesis, which could be targeted for the prevention and treatment of type 2 diabetes.
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Affiliation(s)
- Zhicong Zhao
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China
| | - Xia Deng
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China
| | - Jue Jia
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China
| | - Li Zhao
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China
| | - Chenxi Wang
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China
| | - Zhensheng Cai
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China
| | - Chang Guo
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China
| | - Ling Yang
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China
| | - Dong Wang
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China
| | - Suxian Ma
- Department of Endocrinology, Suzhou Municipal Hospital, Suzhou, Jiangsu 215002, China
| | - Jialiang Deng
- Department of Rheumatology and Immunology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China
| | - Haoxiang Li
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China
| | - Libin Zhou
- Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Shanghai Clinical Center for Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China.
| | - Zhigang Tu
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China.
| | - Guoyue Yuan
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212031, China.
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15
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Abstract
PURPOSE OF REVIEW Elevated LDL-C and triglycerides are important risk factors for the development of atherosclerotic cardiovascular disease. Although effective therapies for lipid lowering exist, many people do not reach their treatment targets. In the last two decades, ANGPTL3 has emerged as a novel therapeutic target for lowering plasma LDL-C and triglycerides. Here, an overview of the recent literature on ANGPTL3 is provided, focusing on the therapeutic benefits of inactivation of ANGPTL3 via monoclonal antibodies, antisense oligonucleotides, and other more nascent approaches. In addition, the potential mechanisms by which ANGPTL3 inactivation lowers plasma LDL-C are discussed. RECENT FINDINGS ANGPTL3 is a factor secreted by the liver that inhibits lipoprotein lipase and other lipases via the formation of a complex with the related protein ANGPTL8. Large-scale genetic studies in humans have shown that carriers of loss-of-function variants in ANGPTL3 have lower plasma LDL-C and triglyceride levels, and are at reduced risk of atherosclerotic cardiovascular disease. Clinical studies in patients with different forms of dyslipidemia have demonstrated that inactivation of ANGPTL3 using monoclonal antibodies or antisense oligonucleotides markedly lowers plasma LDL-C and triglyceride levels. SUMMARY Anti-ANGPTL3 therapies hold considerable promise for reducing plasma LDL-C and triglycerides in selected patient groups.
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Affiliation(s)
- Sander Kersten
- Nutrition, Metabolism and Genomics Group, Division of Human Nutrition and Health, Wageningen University, the Netherlands
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16
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Kaminaga K, Yanagihara H, Genjo T, Morioka T, Abe H, Shirakawa M, Ohshima T, Kakinuma S, Igarashi R. Non-contact measurement of internal body temperature using subcutaneously implanted diamond microparticles. Biomater Sci 2021; 9:7049-7053. [PMID: 34581326 DOI: 10.1039/d1bm01187a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We constructed a highly sensitive fluorescence wide-field imaging system with a microwave source, implanted fluorescent diamond microparticles ("microdiamonds") subcutaneously into the dorsal skin of a mouse after sacrifice, and demonstrated the feasibility of using optically detected magnetic resonance (ODMR) to measure internal body temperature in a mammal.
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Affiliation(s)
- Kiichi Kaminaga
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan. .,National Institute of Radiological Sciences, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Hiromi Yanagihara
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan. .,National Institute of Radiological Sciences, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Takuya Genjo
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan. .,Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Takamitsu Morioka
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan. .,National Institute of Radiological Sciences, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Hiroshi Abe
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan. .,Takasaki Advanced Radiation Research Institute, National Institutes for Quantum Science and Technology, Gunma 370-1292, Japan
| | - Masahiro Shirakawa
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan. .,Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Takeshi Ohshima
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan. .,Takasaki Advanced Radiation Research Institute, National Institutes for Quantum Science and Technology, Gunma 370-1292, Japan
| | - Shizuko Kakinuma
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan. .,National Institute of Radiological Sciences, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Ryuji Igarashi
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan. .,National Institute of Radiological Sciences, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan.,JST, PRESTO, Saitama 332-0012, Japan
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17
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Abstract
Triglyceride-rich lipoproteins deliver fatty acids to tissues for oxidation and for storage. Release of fatty acids from circulating lipoprotein triglycerides is carried out by lipoprotein lipase (LPL), thus LPL serves as a critical gatekeeper of fatty acid uptake into tissues. LPL activity is regulated by a number of extracellular proteins including three members of the angiopoietin-like family of proteins. In this review, we discuss our current understanding of how, where, and when ANGPTL3, ANGPTL4, and ANGPTL8 regulate lipoprotein lipase activity, with a particular emphasis on how these proteins interact with each other to coordinate triglyceride metabolism and fat partitioning.
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Affiliation(s)
- Kelli L Sylvers-Davie
- Department of Biochemistry, Fraternal Order of Eagles Diabetes Research Center, and Obesity Research and Education Initiative, University of Iowa, Iowa City, Iowa
| | - Brandon S J Davies
- Department of Biochemistry, Fraternal Order of Eagles Diabetes Research Center, and Obesity Research and Education Initiative, University of Iowa, Iowa City, Iowa
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18
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Abstract
ANGPTL8 is an important cytokine, which is significantly increased in type 2 diabetes mellitus (T2DM), obesity and metabolic syndrome. Many studies have shown that ANGPTL8 can be used as a bio-marker of these metabolic disorders related diseases, and the baseline ANGPTL8 level has also been found to be positively correlated with retinopathy and all-cause mortality in patients with T2DM. This may be related to the inhibition of lipoprotein lipase activity and the reduction of circulating triglyceride (TG) clearance by ANGPTL8. Consistently, inhibition of ANGPTL8 seems to prevent or improve atherosclerosis. However, it is puzzling that ANGPTL8 seems to have a directing function for TG uptake in peripheral tissues; that is, ANGPTL8 specifically enhances the reserve and buffering function of white adipose tissue, which may alleviate the ectopic lipid accumulation to a certain extent. Furthermore, ANGPTL8 can improve insulin sensitivity and inhibit hepatic glucose production. These contradictory results lead to different opinions on the role of ANGPTL8 in metabolic disorders. In this paper, the correlation between ANGPTL8 and metabolic diseases, the regulation of ANGPTL8 and the physiological role of ANGPTL8 in the process of glucose and lipid metabolism were summarized, and the physiological/pathological significance of ANGPTL8 in the process of metabolic disorder was discussed.
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Affiliation(s)
- Chang Guo
- Department of Nephrology, Affiliated Hospital of Jiangsu University, 438 Jiefang Road, Zhenjiang 212001, Jiangsu, People's Republic of China
| | - Chenxi Wang
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, 438 Jiefang Road, Zhenjiang 212001, Jiangsu, People's Republic of China
| | - Xia Deng
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, 438 Jiefang Road, Zhenjiang 212001, Jiangsu, People's Republic of China
| | - Jianqiang He
- Department of Nephrology, Affiliated Hospital of Jiangsu University, 438 Jiefang Road, Zhenjiang 212001, Jiangsu, People's Republic of China
| | - Ling Yang
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, 438 Jiefang Road, Zhenjiang 212001, Jiangsu, People's Republic of China
| | - Guoyue Yuan
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, 438 Jiefang Road, Zhenjiang 212001, Jiangsu, People's Republic of China
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19
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Townsend LK, Weber AJ, Day EA, Shamshoum H, Shaw SJ, Perry CGR, Kemp BE, Steinberg GR, Wright DC. AMPK mediates energetic stress-induced liver GDF15. FASEB J 2021; 35:e21218. [PMID: 33337559 DOI: 10.1096/fj.202000954r] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 10/30/2020] [Accepted: 11/10/2020] [Indexed: 12/11/2022]
Abstract
Growth differentiating factor-15 (GDF15) is an emerging target for the treatment of obesity and metabolic disease partly due to its ability to suppress food intake. GDF15 expression and secretion are thought to be regulated by a cellular integrated stress response, which involves endoplasmic reticulum (ER) stress. AMPK is another cellular stress sensor, but the relationship between AMPK, ER stress, and GDF15 has not been assessed in vivo. Wildtype (WT), AMPK β1 deficient (AMPKβ1-/- ), and CHOP-/- mice were treated with three distinct AMPK activators; AICAR, which is converted to ZMP mimicking the effects of AMP on the AMPKγ isoform, R419, which indirectly activates AMPK through inhibition of mitochondrial respiration, or A769662, a direct AMPK activator which binds the AMPKβ1 isoform ADaM site causing allosteric activation. Following treatments, liver Gdf15, markers of ER-stress, AMPK activity, adenine nucleotides, circulating GDF15, and food intake were assessed. AICAR and R419 caused ER and energetic stress, increased GDF15 expression and secretion, and suppressed food intake. Direct activation of AMPK β1 containing complexes by A769662 increased hepatic Gdf15 expression, circulating GDF15, and suppressed food intake, independent of ER stress. The effects of AICAR, R419, and A769662 on GDF15 were attenuated in AMPKβ1-/- mice. AICAR and A769662 increased GDF15 to a similar extent in WT and CHOP-/- mice. Herein, we provide evidence that AMPK plays a role in mediating the induction of GDF15 under conditions of energetic stress in mouse liver in vivo.
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Affiliation(s)
- Logan K Townsend
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada.,Centre for Metabolism, Obesity and Diabetes Research and Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - Alyssa J Weber
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| | - Emily A Day
- Centre for Metabolism, Obesity and Diabetes Research and Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - Hesham Shamshoum
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| | - Simon J Shaw
- Rigel Pharmaceuticals Inc., South San Francisco, CA, USA
| | - Christopher G R Perry
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Bruce E Kemp
- Department of Medicine, St. Vincent's Institute, University of Melbourne, Melbourne, Vic, Australia.,Mary MacKillop Institute for Health Research, Australian Catholic University, Fitzroy, Victoria, Australia
| | - Gregory R Steinberg
- Centre for Metabolism, Obesity and Diabetes Research and Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - David C Wright
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
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20
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Bini S, D’Erasmo L, Di Costanzo A, Minicocci I, Pecce V, Arca M. The Interplay between Angiopoietin-Like Proteins and Adipose Tissue: Another Piece of the Relationship between Adiposopathy and Cardiometabolic Diseases? Int J Mol Sci 2021; 22:ijms22020742. [PMID: 33451033 PMCID: PMC7828552 DOI: 10.3390/ijms22020742] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/07/2021] [Accepted: 01/10/2021] [Indexed: 12/15/2022] Open
Abstract
Angiopoietin-like proteins, namely ANGPTL3-4-8, are known as regulators of lipid metabolism. However, recent evidence points towards their involvement in the regulation of adipose tissue function. Alteration of adipose tissue functions (also called adiposopathy) is considered the main inducer of metabolic syndrome (MS) and its related complications. In this review, we intended to analyze available evidence derived from experimental and human investigations highlighting the contribution of ANGPTLs in the regulation of adipocyte metabolism, as well as their potential role in common cardiometabolic alterations associated with adiposopathy. We finally propose a model of ANGPTLs-based adipose tissue dysfunction, possibly linking abnormalities in the angiopoietins to the induction of adiposopathy and its related disorders.
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21
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Nishio M, Saeki K. The Remaining Mysteries about Brown Adipose Tissues. Cells 2020; 9:cells9112449. [PMID: 33182625 PMCID: PMC7696203 DOI: 10.3390/cells9112449] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/20/2020] [Accepted: 11/04/2020] [Indexed: 12/16/2022] Open
Abstract
Brown adipose tissue (BAT), which is a thermogenic fat tissue originally discovered in small hibernating mammals, is believed to exert anti-obesity effects in humans. Although evidence has been accumulating to show the importance of BAT in metabolism regulation, there are a number of unanswered questions. In this review, we show the remaining mysteries about BATs. The distribution of BAT can be visualized by nuclear medicine examinations; however, the precise localization of human BAT is not yet completely understood. For example, studies of 18F-fluorodeoxyglucose PET/CT scans have shown that interscapular BAT (iBAT), the largest BAT in mice, exists only in the neonatal period or in early infancy in humans. However, an old anatomical study illustrated the presence of iBAT in adult humans, suggesting that there is a discrepancy between anatomical findings and imaging data. It is also known that BAT secretes various metabolism-improving factors, which are collectively called as BATokines. With small exceptions, however, their main producers are not BAT per se, raising the possibility that there are still more BATokines to be discovered. Although BAT is conceived as a favorable tissue from the standpoint of obesity prevention, it is also involved in the development of unhealthy conditions such as cancer cachexia. In addition, a correlation between browning of mammary gland and progression of breast cancers was shown in a xenotransplantation model. Therefore, the optimal condition should be carefully determined when BAT is considered as a measure the prevention of obesity and improvement of metabolism. Solving BAT mysteries will open a new door for health promotion via advanced understanding of metabolism regulation system.
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Affiliation(s)
- Miwako Nishio
- Department of Laboratory Molecular Genetics of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo 113-8510, Japan;
| | - Kumiko Saeki
- Department of Laboratory Molecular Genetics of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo 113-8510, Japan;
- Department of Regenerative Medicine, Research Institute, National Center for Global Health and Medicine, Tokyo 162-8655, Japan
- Correspondence: ; Tel.: +81-3-3202-7181
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22
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Abu-Farha M, Ghosh A, Al-Khairi I, Madiraju SRM, Abubaker J, Prentki M. The multi-faces of Angptl8 in health and disease: Novel functions beyond lipoprotein lipase modulation. Prog Lipid Res 2020; 80:101067. [PMID: 33011191 DOI: 10.1016/j.plipres.2020.101067] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 09/17/2020] [Accepted: 09/29/2020] [Indexed: 12/18/2022]
Abstract
Angiopoietin-like protein (ANGPTL) family members, mainly ANGPTL3, ANGPTL4 and ANGPTL8, are physiological inhibitors of lipoprotein lipase (LPL), and play a critical role in lipoprotein and triglyceride metabolism in response to nutritional cues. ANGPTL8 has been described by different names in various studies and has been ascribed various functions at the systemic and cellular levels. Circulating ANGPTL8 originates mainly from the liver and to a smaller extent from adipose tissues. In the blood, ANGPTL8 forms a complex with ANGPTL3 or ANGPTL4 to inhibit LPL in fed or fasted conditions, respectively. Evidence is emerging for additional intracellular and receptor-mediated functions of ANGPTL8, with implications in NFκB mediated inflammation, autophagy, adipogenesis, intra-cellular lipolysis and regulation of circadian clock. Elevated levels of plasma ANGPTL8 are associated with metabolic syndrome, type 2 diabetes, atherosclerosis, hypertension and NAFLD/NASH, even though the precise relationship is not known. Whether ANGPTL8 has direct pathogenic role in these diseases, remains to be explored. In this review, we develop a balanced view on the proposed association of this protein in the regulation of several pathophysiological processes. We also discuss the well-established functions of ANGPTL8 in lipoprotein metabolism in conjunction with the emerging novel extracellular and intracellular roles of ANGPTL8 and the implicated metabolic and signalling pathways. Understanding the diverse functions of ANGPTL8 in various tissues and metabolic states should unveil new opportunities of therapeutic intervention for cardiometabolic disorders.
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Affiliation(s)
- Mohamed Abu-Farha
- Biochemistry and Molecular Biology Unit, Dasman Diabetes Institute, Kuwait City, Kuwait
| | - Anindya Ghosh
- Departments of Nutrition, Biochemistry and Molecular Medicine, Université de Montréal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC, Canada
| | - Irina Al-Khairi
- Biochemistry and Molecular Biology Unit, Dasman Diabetes Institute, Kuwait City, Kuwait
| | - S R Murthy Madiraju
- Departments of Nutrition, Biochemistry and Molecular Medicine, Université de Montréal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC, Canada
| | - Jehad Abubaker
- Biochemistry and Molecular Biology Unit, Dasman Diabetes Institute, Kuwait City, Kuwait..
| | - Marc Prentki
- Departments of Nutrition, Biochemistry and Molecular Medicine, Université de Montréal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC, Canada.
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23
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Lu X. Structure and Function of Angiopoietin-like Protein 3 (ANGPTL3) in Atherosclerosis. Curr Med Chem 2020; 27:5159-5174. [PMID: 31223079 DOI: 10.2174/0929867326666190621120523] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/24/2019] [Accepted: 04/30/2019] [Indexed: 02/08/2023]
Abstract
BACKGROUND Angiopoietin-Like Proteins (ANGPTLs) are structurally related to the angiopoietins. A total of eight ANGPTLs (from ANGPTL1 to ANGPTL8) have been identified so far. Most ANGPTLs possess multibiological functions on lipid metabolism, atherosclerosis, and cancer. Among them, ANGPTL3 has been shown to regulate the levels of Very Low-Density Lipoprotein (VLDL) made by the liver and play a crucial role in human lipoprotein metabolism. METHOD A systematic appraisal of ANGPTLs was conducted, focusing on the main features of ANGPTL3 that has a significant role in atherosclerosis. RESULTS Angiopoietins including ANGPTL3 are vascular growth factors that are highly specific for endothelial cells, perform a variety of other regulatory activities to influence inflammation, and have been shown to possess both pro-atherosclerotic and atheroprotective effects. CONCLUSION ANGPTL3 has been demonstrated as a promising target in the pharmacological management of atherosclerosis. However, many questions remain about its biological functions.
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Affiliation(s)
- Xinjie Lu
- The Mary and Garry Weston Molecular Immunology Laboratory, Thrombosis Research Institute, London SW3 6LR, England, United Kingdom
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24
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Castillo-Armengol J, Barquissau V, Geller S, Ji H, Severi I, Venema W, Fenandez EA, Moret C, Huber K, Leal-Esteban LC, Nasrallah A, Martinez-Carreres L, Niederhäuser G, Seoane-Collazo P, Lagarrigue S, López M, Giordano A, Croizier S, Thorens B, Lopez-Mejia IC, Fajas L. Hypothalamic CDK4 regulates thermogenesis by modulating sympathetic innervation of adipose tissues. EMBO Rep 2020; 21:e49807. [PMID: 32657019 PMCID: PMC7507572 DOI: 10.15252/embr.201949807] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 05/14/2020] [Accepted: 05/28/2020] [Indexed: 01/09/2023] Open
Abstract
This study investigated the role of CDK4 in the oxidative metabolism of brown adipose tissue (BAT). BAT from Cdk4−/− mice exhibited fewer lipids and increased mitochondrial volume and expression of canonical thermogenic genes, rendering these mice more resistant to cold exposure. Interestingly, these effects were not BAT cell‐autonomous but rather driven by increased sympathetic innervation. In particular, the ventromedial hypothalamus (VMH) is known to modulate BAT activation via the sympathetic nervous system. We thus examined the effects of VMH neuron‐specific Cdk4 deletion. These mice display increased sympathetic innervation and enhanced cold tolerance, similar to Cdk4−/− mice, in addition to browning of scWAT. Overall, we provide evidence showing that CDK4 modulates thermogenesis by regulating sympathetic innervation of adipose tissue depots through hypothalamic nuclei, including the VMH. This demonstrates that CDK4 not only negatively regulates oxidative pathways, but also modulates the central regulation of metabolism through its action in the brain.
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Affiliation(s)
| | - Valentin Barquissau
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Sarah Geller
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Honglei Ji
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Ilenia Severi
- Department of Experimental and Clinical Medicine, Marche Polytechnic University, Ancona, Italy
| | - Wiebe Venema
- Department of Experimental and Clinical Medicine, Marche Polytechnic University, Ancona, Italy
| | - Eric Aria Fenandez
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Catherine Moret
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Katharina Huber
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | | | - Anita Nasrallah
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | | | - Guy Niederhäuser
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Patricia Seoane-Collazo
- NeurObesity Group, Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Santiago de Compostela, Spain
| | | | - Miguel López
- NeurObesity Group, Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Santiago de Compostela, Spain
| | - Antonio Giordano
- Department of Experimental and Clinical Medicine, Marche Polytechnic University, Ancona, Italy
| | - Sophie Croizier
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Bernard Thorens
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | | | - Lluis Fajas
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
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25
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Oldoni F, Cheng H, Banfi S, Gusarova V, Cohen JC, Hobbs HH. ANGPTL8 has both endocrine and autocrine effects on substrate utilization. JCI Insight 2020; 5:138777. [PMID: 32730227 PMCID: PMC7526440 DOI: 10.1172/jci.insight.138777] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 07/22/2020] [Indexed: 12/17/2022] Open
Abstract
The angiopoietin-like protein ANGPTL8 (A8) is one of 3 ANGPTLs (A8, A3, A4) that coordinate changes in triglyceride (TG) delivery to tissues by inhibiting lipoprotein lipase (LPL), an enzyme that hydrolyzes TG. Previously we showed that A8, which is expressed in liver and adipose tissue, is required to redirect dietary TG from oxidative to storage tissues following food intake. Here we show that A8 from liver and adipose tissue have different roles in this process. Mice lacking hepatic A8 have no circulating A8, high intravascular LPL activity, low plasma TG levels, and evidence of decreased delivery of dietary lipids to adipose tissue. In contrast, mice lacking A8 in adipose tissue have higher postprandial TG levels and similar intravascular LPL activity and plasma A8 levels and higher levels of plasma TG. Expression of A8, together with A4, in cultured cells reduced A4 secretion and A4-mediated LPL inhibition. Thus, hepatic A8 (with A3) acts in an endocrine fashion to inhibit intravascular LPL in oxidative tissues, whereas A8 in adipose tissue enhances LPL activity by autocrine/paracrine inhibition of A4. These combined actions of A8 ensure that TG stores are rapidly replenished and sufficient energy is available until the next meal. Angiopoietin-like protein ANGPTL8 expressed in liver and adipose tissue partner with ANGPTL3 and ANGPTL4 respectively, and replenish adipose tissue triglyceride stores by distinct endocrine and autocrine/paracrine mechanisms.
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Affiliation(s)
- Federico Oldoni
- Departments of Molecular Genetics and Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Haili Cheng
- Departments of Molecular Genetics and Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Serena Banfi
- Departments of Molecular Genetics and Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | | | | | - Helen H Hobbs
- Departments of Molecular Genetics and Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Howard Hughes Medical Institute, University of Texas Southwestern (UTSW) Medical Center, Dallas, Texas, USA
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26
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Stitziel NO, Kanter JE, Bornfeldt KE. Emerging Targets for Cardiovascular Disease Prevention in Diabetes. Trends Mol Med 2020; 26:744-757. [PMID: 32423639 PMCID: PMC7395866 DOI: 10.1016/j.molmed.2020.03.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 03/18/2020] [Accepted: 03/31/2020] [Indexed: 12/26/2022]
Abstract
Type 1 and type 2 diabetes mellitus (T1DM and T2DM) increase the risk of atherosclerotic cardiovascular disease (CVD), resulting in acute cardiovascular events, such as heart attack and stroke. Recent clinical trials point toward new treatment and prevention strategies for cardiovascular complications of T2DM. New antidiabetic agents show unexpected cardioprotective benefits. Moreover, genetic and reverse translational strategies have revealed potential novel targets for CVD prevention in diabetes, including inhibition of apolipoprotein C3 (APOC3). Modeling and pharmacology-based approaches to improve insulin action provide additional potential strategies to combat CVD. The development of new strategies for improved diabetes and lipid control fuels hope for future prevention of CVD associated with diabetes.
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Affiliation(s)
- Nathan O Stitziel
- Department of Internal Medicine, Cardiovascular Division, Washington University School of Medicine, St Louis, MO 63110, USA; Department of Genetics, Washington University School of Medicine, St Louis, MO 63110, USA; McDonnell Genome Institute, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Jenny E Kanter
- Department of Medicine, Division of Metabolism, Endocrinology and Nutrition, University of Washington Medicine Diabetes Institute, University of Washington School of Medicine, Seattle, WA 98109, USA
| | - Karin E Bornfeldt
- Department of Medicine, Division of Metabolism, Endocrinology and Nutrition, University of Washington Medicine Diabetes Institute, University of Washington School of Medicine, Seattle, WA 98109, USA; Department of Pathology, University of Washington Medicine Diabetes Institute, University of Washington School of Medicine, Seattle, WA 98109, USA.
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27
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Pahlavani M, Ramalingam L, Miller EK, Davis H, Scoggin S, Moustaid-Moussa N. Discordant Dose-Dependent Metabolic Effects of Eicosapentanoic Acid in Diet-Induced Obese Mice. Nutrients 2020; 12:E1342. [PMID: 32397139 PMCID: PMC7284763 DOI: 10.3390/nu12051342] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/01/2020] [Accepted: 05/02/2020] [Indexed: 02/07/2023] Open
Abstract
Obesity is a widespread epidemic that increases the risk for several metabolic diseases. Despite several beneficial health effects of eicosapentaenoic acid (C20:5n-3, EPA), previous studies have used very high doses of EPA. In this study, dose-dependent effects of EPA on metabolic outcomes were determined in diet-induced obese mice. We used B6 male mice, fed high-fat diet (HF, 45% kcal fat) or HF diet supplemented with 9, 18, and 36 g/kg of EPA-enriched fish oil for 14 weeks. We conducted metabolic phenotyping during the feeding period, and harvested tissues and blood at termination. Only mice fed 36 g/kg of EPA significantly (p < 0.05) lowered body weight, fat content and epididymal fat pad weight, compared to HF. Both 18 and 36 g/kg doses of EPA significantly increased glucose clearance and insulin sensitivity, compared to HF or 9 g/kg of EPA. Locomotor activity was significantly increased with both 18 and 36 g/kg doses of EPA. Interestingly, all doses of EPA compared to HF, significantly increased energy expenditure and oxygen consumption and significantly reduced serum insulin, leptin, and triglycerides levels. These results demonstrate weight- and adiposity-independent metabolic benefits of EPA, at doses comparable to those currently used to treat hypertriglyceridemia.
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Affiliation(s)
| | | | | | | | | | - Naima Moustaid-Moussa
- Department of Nutritional Sciences, and Obesity Research Institute, Texas Tech University, Lubbock, TX 79409, USA; (M.P.); (L.R.); (E.K.M.); (H.D.); (S.S.)
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28
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Zhang L, Shannon CE, Bakewell TM, Abdul-Ghani MA, Fourcaudot M, Norton L. Regulation of ANGPTL8 in liver and adipose tissue by nutritional and hormonal signals and its effect on glucose homeostasis in mice. Am J Physiol Endocrinol Metab 2020; 318:E613-E624. [PMID: 32154742 DOI: 10.1152/ajpendo.00339.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The angiopoietin-like protein (ANGPTL) family represents a promising therapeutic target for dyslipidemia, which is a feature of obesity and type 2 diabetes (T2DM). The aim of the present study was to determine the metabolic role of ANGPTL8 and to investigate its nutritional, hormonal, and molecular regulation in key metabolic tissues. The regulation of Angptl8 gene expression by insulin and glucose was quantified using a combination of in vivo insulin clamp experiments in mice and in vitro experiments in primary and cultured hepatocytes and adipocytes. The role of AMPK signaling was examined, and the transcriptional control of Angptl8 was determined using bioinformatic and luciferase reporter approaches. The metabolism of Angptl8 knockout mice (ANGPTL8-/-) was examined following chow and high-fat diets (HFD). Insulin acutely increased Angptl8 expression in liver and adipose tissue, which involved the CCAAT/enhancer-binding protein (C/EBPβ) transcription factor. In insulin clamp experiments, glucose further enhanced Angptl8 expression in the presence of insulin in adipose tissue. The activation of AMPK signaling antagonized the effect of insulin on Angptl8 expression in hepatocytes and adipocytes. The ANGPTL8-/- mice had improved glucose tolerance and displayed reduced fed and fasted plasma triglycerides. However, there was no change in body weight or steatosis in ANGPTL8-/- mice after the HFD. These data show that ANGPTL8 plays important metabolic roles in mice that extend beyond triglyceride metabolism. The finding that insulin, glucose, and AMPK signaling regulate Angptl8 expression may provide important clues about the distinct function of ANGPTL8 in these tissues.
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Affiliation(s)
- Lu Zhang
- Diabetes Division, University of Texas Health Science Center, San Antonio, Texas
| | - Chris E Shannon
- Diabetes Division, University of Texas Health Science Center, San Antonio, Texas
| | - Terry M Bakewell
- Diabetes Division, University of Texas Health Science Center, San Antonio, Texas
| | | | - Marcel Fourcaudot
- Diabetes Division, University of Texas Health Science Center, San Antonio, Texas
| | - Luke Norton
- Diabetes Division, University of Texas Health Science Center, San Antonio, Texas
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29
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Ruscica M, Zimetti F, Adorni MP, Sirtori CR, Lupo MG, Ferri N. Pharmacological aspects of ANGPTL3 and ANGPTL4 inhibitors: New therapeutic approaches for the treatment of atherogenic dyslipidemia. Pharmacol Res 2020; 153:104653. [PMID: 31931117 DOI: 10.1016/j.phrs.2020.104653] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 01/08/2020] [Accepted: 01/09/2020] [Indexed: 12/24/2022]
Abstract
Among the determinants of atherosclerotic cardiovascular disease (ASCVD), genetic and experimental evidence has provided data on a major role of angiopoietin-like proteins 3 and 4 (ANGPTL3 and ANGPTL4) in regulating the activity of lipoprotein lipase (LPL), antagonizing the hydrolysis of triglycerides (TG). Indeed, beyond low-density lipoprotein cholesterol (LDL-C), ASCVD risk is also dependent on a cluster of metabolic abnormalities characterized by elevated fasting and post-prandial levels of TG-rich lipoproteins and their remnants. In a head-to-head comparison between murine models for ANGPTL3 and ANGPTL4, the former was found to be a better pharmacological target for the treatment of hypertriglyceridemia. In humans, loss-of-function mutations of ANGPTL3 are associated with a marked reduction of plasma levels of VLDL, low-density lipoprotein (LDL) and high-density lipoprotein (HDL). Carriers of loss-of-function mutations of ANGPTL4 show instead lower TG-rich lipoproteins and a modest but significant increase of HDL. The relevance of ANGPTL3 and ANGPTL4 as new therapeutic targets is proven by the development of monoclonal antibodies or antisense oligonucleotides. Studies in animal models, including non-human primates, have demonstrated that short-term treatment with monoclonal antibodies against ANGPTL3 and ANGPTL4 induces activation of LPL and a marked reduction of plasma TG-rich-lipoproteins, apparently without any major side effects. Inhibition of both targets also partially reduces LDL-C, independent of the LDL receptor. Similar evidence has been observed with the antisense oligonucleotide ANGPTL3-LRX. The genetic studies have paved the way for the development of new ANGPTL3 and 4 antagonists for the treatment of atherogenic dyslipidemias. Conclusive data of phase 2 and 3 clinical trials are still needed in order to define their safety and efficacy profile.
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Affiliation(s)
- Massimiliano Ruscica
- Dipartimento di Science Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy.
| | - Francesca Zimetti
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università di Parma, Parma, Italy
| | - Maria Pia Adorni
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università di Parma, Parma, Italy
| | - Cesare R Sirtori
- Dyslipidemia Center, A.S.S.T. Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Maria Giovanna Lupo
- Dipartimento di Scienze del Farmaco, Università degli Studi di Padova, Padua, Italy
| | - Nicola Ferri
- Dipartimento di Scienze del Farmaco, Università degli Studi di Padova, Padua, Italy
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30
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Funcke JB, Scherer PE. Beyond adiponectin and leptin: adipose tissue-derived mediators of inter-organ communication. J Lipid Res 2019; 60:1648-1684. [PMID: 31209153 PMCID: PMC6795086 DOI: 10.1194/jlr.r094060] [Citation(s) in RCA: 169] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 06/17/2019] [Indexed: 01/10/2023] Open
Abstract
The breakthrough discoveries of leptin and adiponectin more than two decades ago led to a widespread recognition of adipose tissue as an endocrine organ. Many more adipose tissue-secreted signaling mediators (adipokines) have been identified since then, and much has been learned about how adipose tissue communicates with other organs of the body to maintain systemic homeostasis. Beyond proteins, additional factors, such as lipids, metabolites, noncoding RNAs, and extracellular vesicles (EVs), released by adipose tissue participate in this process. Here, we review the diverse signaling mediators and mechanisms adipose tissue utilizes to relay information to other organs. We discuss recently identified adipokines (proteins, lipids, and metabolites) and briefly outline the contributions of noncoding RNAs and EVs to the ever-increasing complexities of adipose tissue inter-organ communication. We conclude by reflecting on central aspects of adipokine biology, namely, the contribution of distinct adipose tissue depots and cell types to adipokine secretion, the phenomenon of adipokine resistance, and the capacity of adipose tissue to act both as a source and sink of signaling mediators.
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Affiliation(s)
- Jan-Bernd Funcke
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX
| | - Philipp E Scherer
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX
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31
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Circadian lipid synthesis in brown fat maintains murine body temperature during chronic cold. Proc Natl Acad Sci U S A 2019; 116:18691-18699. [PMID: 31451658 DOI: 10.1073/pnas.1909883116] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Ambient temperature influences the molecular clock and lipid metabolism, but the impact of chronic cold exposure on circadian lipid metabolism in thermogenic brown adipose tissue (BAT) has not been studied. Here we show that during chronic cold exposure (1 wk at 4 °C), genes controlling de novo lipogenesis (DNL) including Srebp1, the master transcriptional regulator of DNL, acquired high-amplitude circadian rhythms in thermogenic BAT. These conditions activated mechanistic target of rapamycin 1 (mTORC1), an inducer of Srebp1 expression, and engaged circadian transcriptional repressors REV-ERBα and β as rhythmic regulators of Srebp1 in BAT. SREBP was required in BAT for the thermogenic response to norepinephrine, and depletion of SREBP prevented maintenance of body temperature both during circadian cycles as well as during fasting of chronically cold mice. By contrast, deletion of REV-ERBα and β in BAT allowed mice to maintain their body temperature in chronic cold. Thus, the environmental challenge of prolonged noncircadian exposure to cold temperature induces circadian induction of SREBP1 that drives fuel synthesis in BAT and is necessary to maintain circadian body temperature during chronic cold exposure. The requirement for BAT fatty acid synthesis has broad implications for adaptation to cold.
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32
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Berberine Promotes Beige Adipogenic Signatures of 3T3-L1 Cells by Regulating Post-transcriptional Events. Cells 2019; 8:cells8060632. [PMID: 31234575 PMCID: PMC6627823 DOI: 10.3390/cells8060632] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 06/15/2019] [Accepted: 06/20/2019] [Indexed: 01/11/2023] Open
Abstract
Induced brown adipocytes (also referred to as beige cells) execute thermogenesis, as do the classical adipocytes by consuming stored lipids, being related to metabolic homeostasis. Treatment of phytochemicals, including berberine (BBR), was reported to induce conversion from white adipocytes to beige cells. In this study, results of microRNA (miRNA)-seq analyses revealed a decrease in miR-92a, of which the transcription is driven by the c13orf25 promoter in BBR-treated 3T3-L1 cells. BBR treatment manipulated the expressions of SP1 and MYC, in turn, reducing the activity of the c13orf25 promoter. A decrease in miR-92a led to an increase in RNA-binding motif protein 4a (RBM4a) expression, which facilitated the beige adipogenesis. Overexpression of miR-92a or depletion of RBM4a reversely interfered with the impact of BBR treatment on the beige adipogenic signatures, gene expressions, and splicing events in 3T3-L1 cells. Our findings demonstrated that BBR treatment enhanced beige adipogenesis of 3T3-L1 cells through transcription-coupled post-transcriptional regulation.
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33
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Everything You Always Wanted to Know about β 3-AR * (* But Were Afraid to Ask). Cells 2019; 8:cells8040357. [PMID: 30995798 PMCID: PMC6523418 DOI: 10.3390/cells8040357] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 03/26/2019] [Accepted: 04/12/2019] [Indexed: 12/22/2022] Open
Abstract
The beta-3 adrenergic receptor (β3-AR) is by far the least studied isotype of the beta-adrenergic sub-family. Despite its study being long hampered by the lack of suitable animal and cellular models and inter-species differences, a substantial body of literature on the subject has built up in the last three decades and the physiology of β3-AR is unraveling quickly. As will become evident in this work, β3-AR is emerging as an appealing target for novel pharmacological approaches in several clinical areas involving metabolic, cardiovascular, urinary, and ocular disease. In this review, we will discuss the most recent advances regarding β3-AR signaling and function and summarize how these findings translate, or may do so, into current clinical practice highlighting β3-AR’s great potential as a novel therapeutic target in a wide range of human conditions.
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34
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Townsend LK, Medak KD, Knuth CM, Peppler WT, Charron MJ, Wright DC. Loss of glucagon signaling alters white adipose tissue browning. FASEB J 2019; 33:4824-4835. [PMID: 30615494 DOI: 10.1096/fj.201802048rr] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Various endocrine factors contribute to cold-induced white adipose tissue (WAT) browning, but glucagon has largely been ignored. The purpose of the current investigation was to determine if glucagon was required for the effects of cold on WAT browning. Utilizing whole-body glucagon receptor knockout (Gcgr-/-) mice and their wild-type (WT) littermate controls, we examined the response of inguinal WAT (iWAT) and interscapular brown adipose tissue (BAT) to an acute (48 h) cold stress or challenge with the β3-adrenergic agonist CL316,243. The effects of glucagon alone on the induction of thermogenic genes in adipose tissue from C57BL6/J mice were also examined. Gcgr-/- mice displayed modest increases in indices of browning at room temperature while displaying a blunted induction of Ucp1, Cidea, and Ffg21 mRNA expression in iWAT following cold exposure. Similarly, cold induced increases in mitochondrial DNA copy number, and the protein content of mitochondrial respiratory chain complexes, UCP1, and PGC1α were attenuated in iWAT from Gcgr-/- mice. In BAT, the induction of thermogenic markers following cold exposure was reduced, but the effect was less pronounced than in iWAT. Glucagon treatment increased the expression of thermogenic genes in both iWAT and BAT of C57BL6/J mice. In response to CL316,243, circulating fatty acids, glycerol, and the phosphorylation of hormone-sensitive lipase were attenuated in iWAT of Gcgr-/- mice. We provide evidence that glucagon is sufficient for the induction of thermogenic genes in iWAT, and the absence of intact glucagon signaling blunts the cold-induced browning of WAT, possibly due, in part, to impaired adrenergic signaling.-Townsend, L. K., Medak, K. D., Knuth, C. M., Peppler, W. T., Charron, M. J., Wright, D. C. Loss of glucagon signaling alters white adipose tissue browning.
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Affiliation(s)
- Logan K Townsend
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Kyle D Medak
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Carly M Knuth
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Willem T Peppler
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Maureen J Charron
- Department of Biochemistry, Albert Einstein College of Medicine, New York, New York, USA.,Department of Obstetrics and Gynecology and Women's Health, Albert Einstein College of Medicine, New York, New York, USA; and.,Division of Endocrinology and Diabetes, Department of Medicine, Albert Einstein College of Medicine, New York, New York, USA
| | - David C Wright
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
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35
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Wang R, Yuan J, Zhang C, Wang L, Liu Y, Song L, Zhong W, Chen X, Dong J. Neuropeptide Y-Positive Neurons in the Dorsomedial Hypothalamus Are Involved in the Anorexic Effect of Angptl8. Front Mol Neurosci 2018; 11:451. [PMID: 30618603 PMCID: PMC6305345 DOI: 10.3389/fnmol.2018.00451] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 11/21/2018] [Indexed: 12/22/2022] Open
Abstract
Angiopoietin-like protein 8 (Angptl8), a recently identified member of the angiopoietin-like protein family (ANGPTLs), is a 22-kDa peptide synthesized in the liver. It participates in lipid metabolism by inhibiting lipoprotein lipase (LPL) activity, consequently increasing the triglyceride levels. Despite evidence that Angptl8 is involved in feeding control, the underlying mechanisms are unclear. Central and peripheral injections of Angptl8 significantly decreased food intake. Angptl8 was widely expressed in appetite-related nuclei, including the paraventricular nucleus (PVN), the dorsomedial hypothalamus (DMH), the ventromedial hypothalamus, and the arcuate nucleus (ARC) in the hypothalamus. Peripheral Angptl8 administration decreased c-Fos-positive neurons in the DMH. Central Angptl8 administration decreased c-Fos-positive neurons in the DMH and PVN but increased these neurons in the ARC. Angptl8 inhibited appetite via neuropeptide Y (NPY) neurons in the DMH. Furthermore, the chronic administration of Angptl8 decreased body weight gain and altered adipose tissue deposits. Nevertheless, neither peripheral nor central Angptl8 influenced the brown adipose tissue (BAT) morphology or uncoupling protein 1 (Ucp-1) expression in BAT. Taken together, these data suggested that Angptl8 modulates appetite and energy homeostasis.
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Affiliation(s)
- Rui Wang
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, China
| | - Junhua Yuan
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, China
| | - Caishun Zhang
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, China
| | - Liuxin Wang
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, China
| | - Yuan Liu
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, China
| | - Limin Song
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, China
| | - Weizhen Zhong
- Institute of Foundation Medicine, Medical College, Qingdao University, Qingdao, China
| | - Xi Chen
- Department of Physiology, Medical College, Qingdao University, Qingdao, China
| | - Jing Dong
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, China.,Department of Physiology, Medical College, Qingdao University, Qingdao, China
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Peng HY, Liang YC, Tan TH, Chuang HC, Lin YJ, Lin JC. RBM4a-SRSF3-MAP4K4 Splicing Cascade Constitutes a Molecular Mechanism for Regulating Brown Adipogenesis. Int J Mol Sci 2018; 19:E2646. [PMID: 30200638 PMCID: PMC6163301 DOI: 10.3390/ijms19092646] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 08/24/2018] [Accepted: 09/04/2018] [Indexed: 12/18/2022] Open
Abstract
An increase in mitogen-activated protein kinase kinase kinase kinase 4 (MAP4K4) reportedly attenuates insulin-mediated signaling which participates in the development of brown adipose tissues (BATs). Nevertheless, the effect of MAP4K4 on brown adipogenesis remains largely uncharacterized. In this study, results of a transcriptome analysis (also referred as RNA-sequencing) showed differential expressions of MAP4K4 or SRSF3 transcripts isolated from distinct stages of embryonic BATs. The discriminative splicing profiles of MAP4K4 or SRSF3 were noted as well in brown adipocytes (BAs) with RNA-binding motif protein 4-knockout (RBM4-/-) compared to the wild-type counterparts. Moreover, the relatively high expressions of authentic SRSF3 transcripts encoding the splicing factor functioned as a novel regulator toward MAP4K4 splicing during brown adipogenesis. The presence of alternatively spliced MAP4K4 variants exerted differential effects on the phosphorylation of c-Jun N-terminal protein kinase (JNK) which was correlated with the differentiation or metabolic signature of BAs. Collectively, the RBM4-SRSF3-MAP4K4 splicing cascade constitutes a novel molecular mechanism in manipulating the development of BAs through related signaling pathways.
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Affiliation(s)
- Hui-Yu Peng
- School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
| | - Yu-Chih Liang
- School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
- Ph.D. Program in Medicine Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
| | - Tse-Hua Tan
- Immunology Research Center, National Health Research Institutes, Zhunan 35053, Taiwan.
| | - Huai-Chia Chuang
- Immunology Research Center, National Health Research Institutes, Zhunan 35053, Taiwan.
| | - Ying-Ju Lin
- School of Chinese Medicine, China Medical University, Taichung 40402, Taiwan.
| | - Jung-Chun Lin
- School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
- Ph.D. Program in Medicine Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
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RBM4a modulates the impact of PRDM16 on development of brown adipocytes through an alternative splicing mechanism. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:1515-1525. [PMID: 30327195 DOI: 10.1016/j.bbamcr.2018.08.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 08/02/2018] [Accepted: 08/03/2018] [Indexed: 12/15/2022]
Abstract
Brown adipocytes (BAs) exhibit an energy-expending signature that is important in balancing metabolic homeostasis. In this study, results of transcriptome analyses revealed the reprogrammed splicing profile of the PR domain containing 16 (PRDM16) gene, a key transcription factor involved in brown adipogenesis, throughout development of wild-type brown adipose tissues (BATs). Moreover, discriminative splicing patterns of PRDM16 transcripts were noted in embryonic and postnatal RBM4a-/- BATs. Overexpression of RBM4a enhanced the relative levels of PRDM16-ex 16 transcripts by simultaneously interacting with exonic and intronic CU elements, which encoded the PRDM16S isoform containing a distinct C-terminus. The presence of the overexpressed PRDM16S isoform showed a stronger effect than the overexpressed PRDM16L isoform on enhancing transcriptional activity of the RBM4a and the PGC-1α promoter. Overexpression of the PRDM16S isoform exerted more-prominent effects on enhancing the BAT-related gene program and energy expenditure compared to those of PRDM16L-overexpressing cells. Our studies demonstrated that RBM4a-regulated alternative splicing constituted another regulatory mechanism for strengthening the influence of PRDM16 on the development of brown adipocytes.
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