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Ritter ML, Wagner VA, Balapattabi K, Opichka MA, Lu KT, Wackman KK, Reho JJ, Keen HL, Kwitek AE, Morselli LL, Geurts AM, Sigmund CD, Grobe JL. Krüppel-like factor 4 in transcriptional control of the three unique isoforms of Agouti-related peptide in mice. Physiol Genomics 2024; 56:265-275. [PMID: 38145289 PMCID: PMC10866620 DOI: 10.1152/physiolgenomics.00042.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 11/15/2023] [Accepted: 12/21/2023] [Indexed: 12/26/2023] Open
Abstract
Agouti-related peptide (AgRP/Agrp) within the hypothalamic arcuate nucleus (ARC) contributes to the control of energy balance, and dysregulated Agrp may contribute to metabolic adaptation during prolonged obesity. In mice, three isoforms of Agrp are encoded via distinct first exons. Agrp-A (ENSMUST00000005849.11) contributed 95% of total Agrp in mouse ARC, whereas Agrp-B (ENSMUST00000194654.2) dominated in placenta (73%). Conditional deletion of Klf4 from Agrp-expressing cells (Klf4Agrp-KO mice) reduced Agrp mRNA and increased energy expenditure but had no effects on food intake or the relative abundance of Agrp isoforms in the ARC. Chronic high-fat diet feeding masked these effects of Klf4 deletion, highlighting the context-dependent contribution of KLF4 to Agrp control. In the GT1-7 mouse hypothalamic cell culture model, which expresses all three isoforms of Agrp (including Agrp-C, ENSMUST00000194091.6), inhibition of extracellular signal-regulated kinase (ERK) simultaneously increased KLF4 binding to the Agrp promoter and stimulated Agrp expression. In addition, siRNA-mediated knockdown of Klf4 reduced expression of Agrp. We conclude that the expression of individual isoforms of Agrp in the mouse is dependent upon cell type and that KLF4 directly promotes the transcription of Agrp via a mechanism that is superseded during obesity.NEW & NOTEWORTHY In mice, three distinct isoforms of Agouti-related peptide are encoded via distinct first exons. In the arcuate nucleus of the hypothalamus, Krüppel-like factor 4 stimulates transcription of the dominant isoform in lean mice, but this mechanism is altered during diet-induced obesity.
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Affiliation(s)
- McKenzie L Ritter
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Valerie A Wagner
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Genetics Graduate Program, University of Iowa, Iowa City, Iowa, United States
| | - Kirthikaa Balapattabi
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Megan A Opichka
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Ko-Ting Lu
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Kelsey K Wackman
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - John J Reho
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Comprehensive Rodent Metabolic Phenotyping Core, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Henry L Keen
- Bioinformatics Division, Institute of Human Genetics, University of Iowa, Iowa City, Iowa, United States
| | - Anne E Kwitek
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Linda T. and John A. Mellowes Center for Genomic Sciences and Precision Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Lisa L Morselli
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Division of Endocrinology and Molecular Medicine, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Aron M Geurts
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Linda T. and John A. Mellowes Center for Genomic Sciences and Precision Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Curt D Sigmund
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Justin L Grobe
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Comprehensive Rodent Metabolic Phenotyping Core, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
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Cai J, Chen J, Ortiz-Guzman J, Huang J, Arenkiel BR, Wang Y, Zhang Y, Shi Y, Tong Q, Zhan C. AgRP neurons are not indispensable for body weight maintenance in adult mice. Cell Rep 2023; 42:112789. [PMID: 37422762 PMCID: PMC10909125 DOI: 10.1016/j.celrep.2023.112789] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 05/16/2023] [Accepted: 06/23/2023] [Indexed: 07/11/2023] Open
Abstract
In addition to their role in promoting feeding and obesity development, hypothalamic arcuate agouti-related protein/neuropeptide Y (AgRP/NPY) neurons are widely perceived to be indispensable for maintaining normal feeding and body weight in adults, and consistently, acute inhibition of AgRP neurons is known to reduce short-term food intake. Here, we adopted complementary methods to achieve nearly complete ablation of arcuate AgRP/NPY neurons in adult mice and report that lesioning arcuate AgRP/NPY neurons in adult mice causes no apparent alterations in ad libitum feeding or body weight. Consistent with previous studies, loss of AgRP/NPY neurons blunts fasting refeeding. Thus, our studies show that AgRP/NPY neurons are not required for maintaining ad libitum feeding or body weight homeostasis in adult mice.
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Affiliation(s)
- Jing Cai
- Brown Institute of Molecular Medicine at McGovern Medical School and Neuroscience Program of MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Jing Chen
- School of Sport Science, Beijing Sport University, Beijing 100084, China
| | - Joshua Ortiz-Guzman
- Duncan Institute of Neurological Research and Department of Neuroscience and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jessica Huang
- Brown Institute of Molecular Medicine at McGovern Medical School and Neuroscience Program of MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Benjamin R Arenkiel
- Duncan Institute of Neurological Research and Department of Neuroscience and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yuchen Wang
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Hematology, The First Affiliated Hospital of USTC, CAS Key Laboratory of Brain Function and Disease, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Biomedical Sciences and Health Laboratory of Anhui Province, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China
| | - Yan Zhang
- School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Yuyan Shi
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Hematology, The First Affiliated Hospital of USTC, CAS Key Laboratory of Brain Function and Disease, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Biomedical Sciences and Health Laboratory of Anhui Province, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China
| | - Qingchun Tong
- Brown Institute of Molecular Medicine at McGovern Medical School and Neuroscience Program of MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
| | - Cheng Zhan
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Hematology, The First Affiliated Hospital of USTC, CAS Key Laboratory of Brain Function and Disease, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Biomedical Sciences and Health Laboratory of Anhui Province, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China.
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Haspula D, Cui Z. Neurochemical Basis of Inter-Organ Crosstalk in Health and Obesity: Focus on the Hypothalamus and the Brainstem. Cells 2023; 12:1801. [PMID: 37443835 PMCID: PMC10341274 DOI: 10.3390/cells12131801] [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: 05/15/2023] [Revised: 06/23/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023] Open
Abstract
Precise neural regulation is required for maintenance of energy homeostasis. Essential to this are the hypothalamic and brainstem nuclei which are located adjacent and supra-adjacent to the circumventricular organs. They comprise multiple distinct neuronal populations which receive inputs not only from other brain regions, but also from circulating signals such as hormones, nutrients, metabolites and postprandial signals. Hence, they are ideally placed to exert a multi-tier control over metabolism. The neuronal sub-populations present in these key metabolically relevant nuclei regulate various facets of energy balance which includes appetite/satiety control, substrate utilization by peripheral organs and glucose homeostasis. In situations of heightened energy demand or excess, they maintain energy homeostasis by restoring the balance between energy intake and expenditure. While research on the metabolic role of the central nervous system has progressed rapidly, the neural circuitry and molecular mechanisms involved in regulating distinct metabolic functions have only gained traction in the last few decades. The focus of this review is to provide an updated summary of the mechanisms by which the various neuronal subpopulations, mainly located in the hypothalamus and the brainstem, regulate key metabolic functions.
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Affiliation(s)
- Dhanush Haspula
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892, USA
| | - Zhenzhong Cui
- Mouse Metabolism Core, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892, USA;
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