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Meng X, Wu W, Tang Y, Peng M, Yang J, Yuan S, Hu Z, Liu W. Lactate/Hydroxycarboxylic Acid Receptor 1 in Alzheimer's Disease: Mechanisms and Therapeutic Implications-Exercise Perspective. Mol Neurobiol 2024; 61:7717-7731. [PMID: 38427215 DOI: 10.1007/s12035-024-04067-x] [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: 09/22/2023] [Accepted: 02/21/2024] [Indexed: 03/02/2024]
Abstract
Lactate has a novel function different from previously known functions despite its traditional association with hypoxia in skeletal muscle. It plays various direct and indirect physiological functions. It is a vital energy source within the central nervous system (CNS) and a signal transmitter regulating crucial processes, such as angiogenesis and inflammation. Activating lactate and its associated receptors elicits effects like synaptic plasticity and angiogenesis alterations. These effects can significantly influence the astrocyte-neuron lactate shuttle, potentially impacting cognitive performance. Decreased cognitive function relates to different neurodegenerative conditions, including Alzheimer's disease (AD), ischemic brain injury, and frontotemporal dementia. Therefore, lactic acid has significant potential for treating neurodegenerative disorders. Exercise is a method that induces the production of lactic acid, which is similar to the effect of lactate injections. It is a harmless and natural way to achieve comparable results. Animal experiments demonstrate that high-intensity intermittent exercise can increase vascular endothelial growth factor (VEGF) levels, thus promoting angiogenesis. In vivo, lactate receptor-hydroxycarboxylic acid receptor 1 (HCAR1) activation can occur by various stimuli, including variations in ion concentrations, cyclic adenosine monophosphate (cAMP) level elevations, and fluctuations in the availability of energy substrates. While several articles have been published on the benefits of physical activity on developing Alzheimer's disease in the CNS, could lactic acid act as a bridge? Understanding how HCAR1 responds to these signals and initiates associated pathways remains incomplete. This review comprehensively analyzes lactate-induced signaling pathways, investigating their influence on neuroinflammation, neurodegeneration, and cognitive decline. Consequently, this study describes the unique role of lactate in the progression of Alzheimer's disease.
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Affiliation(s)
- Xiangyuan Meng
- Hunan Provincial Key Laboratory of Physical Fitness and Sports Rehabilitation, Hunan Normal University, Changsha, 410012, China
| | - Weijia Wu
- Hunan Provincial Key Laboratory of Physical Fitness and Sports Rehabilitation, Hunan Normal University, Changsha, 410012, China
| | - Yingzhe Tang
- Hunan Provincial Key Laboratory of Physical Fitness and Sports Rehabilitation, Hunan Normal University, Changsha, 410012, China
| | - Mei Peng
- Hunan Provincial Key Laboratory of Physical Fitness and Sports Rehabilitation, Hunan Normal University, Changsha, 410012, China
| | - Jialun Yang
- Hunan Provincial Key Laboratory of Physical Fitness and Sports Rehabilitation, Hunan Normal University, Changsha, 410012, China
| | - Shunling Yuan
- Hunan Provincial Key Laboratory of Physical Fitness and Sports Rehabilitation, Hunan Normal University, Changsha, 410012, China
| | - Zelin Hu
- Hunan Provincial Key Laboratory of Physical Fitness and Sports Rehabilitation, Hunan Normal University, Changsha, 410012, China
| | - Wenfeng Liu
- Hunan Provincial Key Laboratory of Physical Fitness and Sports Rehabilitation, Hunan Normal University, Changsha, 410012, China.
- Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, Hunan Normal University, Changsha, 410081, China.
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Kozai A, Murakami R, Chiba Y, Miyai Y, Matsumoto K, Kanenishi K, Ueno M. Immunohistochemical localization of HCA1 receptor in placenta in presence of fetal growth restriction. Placenta 2024; 154:80-87. [PMID: 38909565 DOI: 10.1016/j.placenta.2024.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 06/06/2024] [Accepted: 06/18/2024] [Indexed: 06/25/2024]
Abstract
INTRODUCTION Glucose metabolism produces lactate and hydrogen ions in an anaerobic environment. Fetuses with intrauterine growth restriction are considered to become progressively lactacidemic as well as hypoxic. Roles of lactate in the placenta in the presence of fetal growth restriction (FGR) remain to be clarified. METHODS Immunohistochemical localization of lactate-related substances, such as a receptor for lactate (hydroxy-carboxylic acid 1 receptor (HCA1 receptor/GPR81)), monocarboxylate transporters (MCTs) for lactate, lactate dehydrogenases (LDHs), and proteins expressed in syncytiotrophoblasts or cytotrophoblasts was examined in placentas of appropriate weight for gestational age (AGA) fetus and those showing FGR. RESULTS Immunoreactivity for the HCA1 receptor was present in the cytoplasm of some trophoblasts, predominantly localized to their basal (fetus-facing) side, and was frequently colocalized with that for E-cadherin or serine peptidase inhibitor, Kunitz type 1 (SPINT1), a marker protein of cytotrophoblasts. Immunoreactivity for MCT1 and MCT4 was present on the basal and the microvillous (maternal-facing) membranes of trophoblasts in both groups, respectively. Clear immunoreactivity for LDHA and LDHB was also observed in the cytoplasm of trophoblasts, mainly localized to their basal side. However, there were no significant differences in immunohistochemically stained areas of lactate-related substances between AGA and late-onset FGR groups. On the other hand, there were correlations between coefficients of the presence of chorioamnionitis and the values of LDHB and E-cadherin. DISCUSSION Immunohistochemical localization of the HCA1 receptor was predominantly observed in the cytoplasm located on the basal side of trophoblasts, suggesting a role of lactate in human placental development, including syncytialization.
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Affiliation(s)
- Ayumi Kozai
- Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan; Department of Perinatology and Gynecology, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Ryuta Murakami
- Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Yoichi Chiba
- Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Yumi Miyai
- Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Koichi Matsumoto
- Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Kenji Kanenishi
- Department of Perinatology and Gynecology, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Masaki Ueno
- Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan.
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Zhi Y, Fan K, Liu S, Hu K, Zan X, Lin L, Yang Y, Gong X, Chen K, Tang L, Li L, Huang J, Zhang S, Zhang L. Deletion of GPR81 activates CREB/Smad7 pathway and alleviates liver fibrosis in mice. Mol Med 2024; 30:99. [PMID: 38982366 PMCID: PMC11234765 DOI: 10.1186/s10020-024-00867-y] [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: 11/17/2023] [Accepted: 06/24/2024] [Indexed: 07/11/2024] Open
Abstract
BACKGROUND Enhanced glycolysis is a crucial metabolic event that drives the development of liver fibrosis, but the molecular mechanisms have not been fully understood. Lactate is the endproduct of glycolysis, which has recently been identified as a bioactive metabolite binding to G-protein-coupled receptor 81 (GPR81). We then questioned whether GPR81 is implicated in the development of liver fibrosis. METHODS The level of GPR81 was determined in mice with carbon tetrachloride (CCl4)-induced liver fibrosis and in transforming growth factor beta 1 (TGF-β1)-activated hepatic stellate cells (HSCs) LX-2. To investigate the significance of GPR81 in liver fibrosis, wild-type (WT) and GPR81 knockout (KO) mice were exposed to CCl4, and then the degree of liver fibrosis was determined. In addition, the GPR81 agonist 3,5-dihydroxybenzoic acid (DHBA) was supplemented in CCl4-challenged mice and TGF-β1-activated LX-2 cells to further investigate the pathological roles of GPR81 on HSCs activation. RESULTS CCl4 exposure or TGF-β1 stimulation significantly upregulated the expression of GPR81, while deletion of GPR81 alleviated CCl4-induced elevation of aminotransferase, production of pro-inflammatory cytokines, and deposition of collagen. Consistently, the production of TGF-β1, the expression of alpha-smooth muscle actin (α-SMA) and collagen I (COL1A1), as well as the elevation of hydroxyproline were suppressed in GPR81 deficient mice. Supplementation with DHBA enhanced CCl4-induced liver fibrogenesis in WT mice but not in GPR81 KO mice. DHBA also promoted TGF-β1-induced LX-2 activation. Mechanistically, GPR81 suppressed cAMP/CREB and then inhibited the expression of Smad7, a negative regulator of Smad3, which resulted in increased phosphorylation of Smad3 and enhanced activation of HSCs. CONCLUSION GPR81 might be a detrimental factor that promotes the development of liver fibrosis by regulating CREB/Smad7 pathway.
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Affiliation(s)
- Ying Zhi
- Department of Pathophysiology, Basic Medical College, Chongqing Medical University, 1 Yixueyuan Road, Chongqing, 400016, China
- Laboratory of Stem Cell and Tissue Engineering, Chongqing Medical University, Chongqing, China
| | - Kerui Fan
- Laboratory of Stem Cell and Tissue Engineering, Chongqing Medical University, Chongqing, China
- Department of Anatomy, Basic Medical College, Chongqing Medical University, Chongqing, China
| | - Shuang Liu
- Department of Pathophysiology, Basic Medical College, Chongqing Medical University, 1 Yixueyuan Road, Chongqing, 400016, China
| | - Kai Hu
- Department of Pathophysiology, Basic Medical College, Chongqing Medical University, 1 Yixueyuan Road, Chongqing, 400016, China
| | - Xinyan Zan
- Department of Pathophysiology, Basic Medical College, Chongqing Medical University, 1 Yixueyuan Road, Chongqing, 400016, China
| | - Ling Lin
- Department of Pathophysiology, Basic Medical College, Chongqing Medical University, 1 Yixueyuan Road, Chongqing, 400016, China
| | - Yongqiang Yang
- Department of Pathophysiology, Basic Medical College, Chongqing Medical University, 1 Yixueyuan Road, Chongqing, 400016, China
| | - Xianqiong Gong
- Hepatology Center, Xiamen Hospital of Traditional Chinese Medicine, Xiamen, Fujian, China
| | - Kun Chen
- Department of Pathophysiology, Basic Medical College, Chongqing Medical University, 1 Yixueyuan Road, Chongqing, 400016, China
| | - Li Tang
- Department of Pathophysiology, Basic Medical College, Chongqing Medical University, 1 Yixueyuan Road, Chongqing, 400016, China
| | - Longjiang Li
- Department of Pathophysiology, Basic Medical College, Chongqing Medical University, 1 Yixueyuan Road, Chongqing, 400016, China
| | - Jiayi Huang
- Department of Pathophysiology, Basic Medical College, Chongqing Medical University, 1 Yixueyuan Road, Chongqing, 400016, China
| | - Shujun Zhang
- Chongqing Key Laboratory of Infectious Diseases and Parasitic Diseases, Department of Infectious Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
| | - Li Zhang
- Department of Pathophysiology, Basic Medical College, Chongqing Medical University, 1 Yixueyuan Road, Chongqing, 400016, China.
- Laboratory of Integrated Traditional and Western Medicine, Chongqing Traditional Chinese Medicine Hospital, Chongqing, 400011, China.
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Caviness PC, Lazarenko OP, Blackburn ML, Chen JF, Randolph CE, Zabaleta J, Zhan F, Chen JR. Phenolic acids prevent sex-steroid deficiency-induced bone loss and bone marrow adipogenesis in mice. J Nutr Biochem 2024; 127:109601. [PMID: 38367948 DOI: 10.1016/j.jnutbio.2024.109601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 01/19/2024] [Accepted: 02/12/2024] [Indexed: 02/19/2024]
Abstract
Phenolic acids, such as hippuric acid (HA) and 3-(3-hydroxyphenyl) propionic acid (3-3-PPA), can be produced from microbiome digestion of polyphenols. Previously it was found that HA and 3-3-PPA facilitate bone formation and suppress bone resorption. However, the mechanism of action by which HA and 3-3-PPA protect bone from degeneration is currently unknown. In this report, we present that HA and 3-3-PPA suppression of bone resorption is able to ameliorate bone loss in an ovariectomy (OVX) osteopenic mouse model though not to the extent of Zoledronic acid (ZA). HA and 3-3-PPA treatments were shown to significantly decrease bone marrow adipocyte-like cell formation and inhibited gene expression of key adipogenesis regulator peroxisome proliferator activated receptor gamma (PPARγ) and lipoprotein lipase (Lpl) in bone from OVX mice. In addition, ChIP experiments showed that the association between PPARγ and Lpl promoter region in preadipocyte-like cells was significantly suppressed following HA or 3-3-PPA treatment. Contrasting HA and 3-3-PPA, ZA significantly increased TRAP activity in the area close to growth plate and significantly suppressed bone cell proliferation. These data suggest that phenolics acids such as HA or 3-3-PPA may prevent bone degeneration after OVX through suppression of inflammatory milieu in the bone.
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Affiliation(s)
- Perry C Caviness
- Arkansas Children's Nutrition Center, Little Rock, Arkansas 72205, USA; Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
| | - Oxana P Lazarenko
- Arkansas Children's Nutrition Center, Little Rock, Arkansas 72205, USA; Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
| | - Michael L Blackburn
- Arkansas Children's Nutrition Center, Little Rock, Arkansas 72205, USA; Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
| | - Jennifer F Chen
- Undergraduate Pre-Medical Program, University of Arkansas at Fayetteville, Fayetteville, Arkansas 72701, USA
| | - Christopher E Randolph
- Center for Translational Pediatric Research, Arkansas Children's Research Institute, Little Rock, Arkansas 72202, USA
| | - Jovanny Zabaleta
- Department of Interdisciplinary Oncology, Louisiana State University Health Sciences Center, New Orleans, Los Angeles 70112, USA
| | - Fenghuang Zhan
- Myeloma Center, Winthrop P. Rockefeller Cancer Institute, Department of Internal Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Jin-Ran Chen
- Arkansas Children's Nutrition Center, Little Rock, Arkansas 72205, USA; Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
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Cai M, Li S, Cai K, Du X, Han J, Hu J. Empowering mitochondrial metabolism: Exploring L-lactate supplementation as a promising therapeutic approach for metabolic syndrome. Metabolism 2024; 152:155787. [PMID: 38215964 DOI: 10.1016/j.metabol.2024.155787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 12/08/2023] [Accepted: 01/05/2024] [Indexed: 01/14/2024]
Abstract
Mitochondrial dysfunction plays a critical role in the pathogenesis of metabolic syndrome (MetS), affecting various cell types and organs. In MetS animal models, mitochondria exhibit decreased quality control, characterized by abnormal morphological structure, impaired metabolic activity, reduced energy production, disrupted signaling cascades, and oxidative stress. The aberrant changes in mitochondrial function exacerbate the progression of metabolic syndrome, setting in motion a pernicious cycle. From this perspective, reversing mitochondrial dysfunction is likely to become a novel and powerful approach for treating MetS. Unfortunately, there are currently no effective drugs available in clinical practice to improve mitochondrial function. Recently, L-lactate has garnered significant attention as a valuable metabolite due to its ability to regulate mitochondrial metabolic processes and function. It is highly likely that treating MetS and its related complications can be achieved by correcting mitochondrial homeostasis disorders. In this review, we comprehensively discuss the complex relationship between mitochondrial function and MetS and the involvement of L-lactate in regulating mitochondrial metabolism and associated signaling pathways. Furthermore, it highlights recent findings on the involvement of L-lactate in common pathologies of MetS and explores its potential clinical application and further prospects, thus providing new insights into treatment possibilities for MetS.
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Affiliation(s)
- Ming Cai
- College of Rehabilitation Sciences, Shanghai University of Medicine and Health Sciences, Shanghai 201318, PR China; Bio-X Institutes, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Shuyao Li
- College of Rehabilitation Sciences, Shanghai University of Medicine and Health Sciences, Shanghai 201318, PR China
| | - Keren Cai
- College of Rehabilitation Sciences, Shanghai University of Medicine and Health Sciences, Shanghai 201318, PR China
| | - Xinlin Du
- College of Rehabilitation Sciences, Shanghai University of Medicine and Health Sciences, Shanghai 201318, PR China
| | - Jia Han
- College of Rehabilitation Sciences, Shanghai University of Medicine and Health Sciences, Shanghai 201318, PR China.
| | - Jingyun Hu
- Central Lab, Shanghai Key Laboratory of Pathogenic Fungi Medical Testing, Shanghai Pudong New Area People's Hospital, Shanghai 201299, PR China.
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Mohammad Nezhady MA, Modaresinejad M, Zia A, Chemtob S. Versatile lactate signaling via HCAR1: a multifaceted GPCR involved in many biological processes. Am J Physiol Cell Physiol 2023; 325:C1502-C1515. [PMID: 37899751 DOI: 10.1152/ajpcell.00346.2023] [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: 07/31/2023] [Revised: 10/17/2023] [Accepted: 10/17/2023] [Indexed: 10/31/2023]
Abstract
G-coupled protein receptors (GPCRs) are the ultimate refuge of pharmacology and medicine as more than 40% of all marketed drugs are directly targeting these receptors. Through cell surface expression, they are at the forefront of cellular communication with the outside world. Metabolites among the conveyors of this communication are becoming more prominent with the recognition of them as ligands for GPCRs. HCAR1 is a GPCR conveyor of lactate. It is a class A GPCR coupled to Gαi which reduces cellular cAMP along with the downstream Gβγ signaling. It was first found to inhibit lipolysis, and lately has been implicated in diverse cellular processes, including neural activities, angiogenesis, inflammation, vision, cardiovascular function, stem cell proliferation, and involved in promoting pathogenesis for different conditions, such as cancer. Other than signaling from the plasma membrane, HCAR1 shows nuclear localization with different location-biased activities therein. Although different functions for HCAR1 are being discovered, its cell and molecular mechanisms are yet ill understood. Here, we provide a comprehensive review on HCAR1, which covers the literature on the subject, and discusses its importance and relevance in various biological phenomena.
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Affiliation(s)
- Mohammad Ali Mohammad Nezhady
- Molecular Biology Program, Faculty of Medicine, Université de Montréal, Montreal, Quebec, Canada
- Research Center of Centre Hospitalier Universitaire Sainte-Justine, Montreal, Quebec, Canada
| | - Monir Modaresinejad
- Research Center of Centre Hospitalier Universitaire Sainte-Justine, Montreal, Quebec, Canada
- Biomedical Sciences Program, Faculty of Medicine, Université de Montréal, Montreal, Quebec, Canada
| | - Aliabbas Zia
- Research Center of Centre Hospitalier Universitaire Sainte-Justine, Montreal, Quebec, Canada
- Department of Pharmacology, Université de Montréal, Montreal, Quebec, Canada
| | - Sylvain Chemtob
- Molecular Biology Program, Faculty of Medicine, Université de Montréal, Montreal, Quebec, Canada
- Research Center of Centre Hospitalier Universitaire Sainte-Justine, Montreal, Quebec, Canada
- Department of Pharmacology, Université de Montréal, Montreal, Quebec, Canada
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Colucci ACM, Tassinari ID, Loss EDS, de Fraga LS. History and Function of the Lactate Receptor GPR81/HCAR1 in the Brain: A Putative Therapeutic Target for the Treatment of Cerebral Ischemia. Neuroscience 2023; 526:144-163. [PMID: 37391123 DOI: 10.1016/j.neuroscience.2023.06.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 06/21/2023] [Accepted: 06/24/2023] [Indexed: 07/02/2023]
Abstract
GPR81 is a G-protein coupled receptor (GPCR) discovered in 2001, but deorphanized only 7 years later, when its affinity for lactate as an endogenous ligand was demonstrated. More recently, GPR81 expression and distribution in the brain were also confirmed and the function of lactate as a volume transmitter has been suggested since then. These findings shed light on a new function of lactate acting as a signaling molecule in the central nervous system, in addition to its well-known role as a metabolic fuel for neurons. GPR81 seems to act as a metabolic sensor, coupling energy metabolism, synaptic activity, and blood flow. Activation of this receptor leads to Gi-mediated downregulation of adenylyl cyclase and subsequent reduction in cAMP levels, regulating several downstream pathways. Recent studies have also suggested the potential role of lactate as a neuroprotective agent, mainly under brain ischemic conditions. This effect is usually attributed to the metabolic role of lactate, but the underlying mechanisms need further investigation and could be related to lactate signaling via GPR81. The activation of GPR81 showed promising results for neuroprotection: it modulates many processes involved in the pathophysiology of ischemia. In this review, we summarize the history of GPR81, starting with its deorphanization; then, we discuss GPR81 expression and distribution, signaling transduction cascades, and neuroprotective roles. Lastly, we propose GPR81 as a potential target for the treatment of cerebral ischemia.
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Affiliation(s)
- Anna Clara Machado Colucci
- Laboratório de Neurobiologia e Metabolismo (NeuroMet), Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, lab. 660, Porto Alegre, Brazil; Programa de Pós-Graduação em Ciências Biológicas: Fisiologia, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, Porto Alegre, Brazil; Centro de Pesquisa Experimental, Hospital de Clínicas de Porto Alegre (HCPA), Rua Ramiro Barcelos, 2350, Porto Alegre, Brazil
| | - Isadora D'Ávila Tassinari
- Laboratório de Neurobiologia e Metabolismo (NeuroMet), Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, lab. 660, Porto Alegre, Brazil; Programa de Pós-Graduação em Ciências Biológicas: Fisiologia, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, Porto Alegre, Brazil; Centro de Pesquisa Experimental, Hospital de Clínicas de Porto Alegre (HCPA), Rua Ramiro Barcelos, 2350, Porto Alegre, Brazil
| | - Eloísa da Silveira Loss
- Laboratório de Endocrinologia Experimental (LABENEX), Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, lab. 660, Porto Alegre, Brazil; Programa de Pós-Graduação em Ciências Biológicas: Fisiologia, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, Porto Alegre, Brazil
| | - Luciano Stürmer de Fraga
- Laboratório de Neurobiologia e Metabolismo (NeuroMet), Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, lab. 660, Porto Alegre, Brazil; Programa de Pós-Graduação em Ciências Biológicas: Fisiologia, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600, Porto Alegre, Brazil; Centro de Pesquisa Experimental, Hospital de Clínicas de Porto Alegre (HCPA), Rua Ramiro Barcelos, 2350, Porto Alegre, Brazil.
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Tao H, Zhong X, Zeng A, Song L. Unveiling the veil of lactate in tumor-associated macrophages: a successful strategy for immunometabolic therapy. Front Immunol 2023; 14:1208870. [PMID: 37564659 PMCID: PMC10411982 DOI: 10.3389/fimmu.2023.1208870] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 07/12/2023] [Indexed: 08/12/2023] Open
Abstract
Lactate, traditionally regarded as a metabolic waste product at the terminal of the glycolysis process, has recently been found to have multifaceted functional roles in metabolism and beyond. A metabolic reprogramming phenomenon commonly seen in tumor cells, known as the "Warburg effect," sees high levels of aerobic glycolysis result in an excessive production of lactate. This lactate serves as a substrate that sustains not only the survival of cancer cells but also immune cells. However, it also inhibits the function of tumor-associated macrophages (TAMs), a group of innate immune cells ubiquitously present in solid tumors, thereby facilitating the immune evasion of malignant tumor cells. Characterized by their high plasticity, TAMs are generally divided into the pro-inflammatory M1 phenotype and the pro-tumour M2 phenotype. Through a process of 'education' by lactate, TAMs tend to adopt an immunosuppressive phenotype and collaborate with tumor cells to promote angiogenesis. Additionally, there is growing evidence linking metabolic reprogramming with epigenetic modifications, suggesting the participation of histone modification in diverse cellular events within the tumor microenvironment (TME). In this review, we delve into recent discoveries concerning lactate metabolism in tumors, with a particular focus on the impact of lactate on the function of TAMs. We aim to consolidate the molecular mechanisms underlying lactate-induced TAM polarization and angiogenesis and explore the lactate-mediated crosstalk between TAMs and tumor cells. Finally, we also touch upon the latest progress in immunometabolic therapies and drug delivery strategies targeting glycolysis and lactate production, offering new perspectives for future therapeutic approaches.
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Affiliation(s)
- Hongxia Tao
- School of Medical and Life Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Xuansheng Zhong
- Clinical Medicine Department, Bengbu Medical College, Bengbu, China
| | - Anqi Zeng
- Institute of Translational Pharmacology and Clinical Application, Sichuan Academy of Chinese Medical Science, Chengdu, Sichuan, China
| | - Linjiang Song
- School of Medical and Life Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
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Qi J, Yang Q, Xia Q, Huang F, Guo H, Cui H, Xie Y, Ren Z, Gou L, Cai D, Kumbhar MA, Fang J, Zuo Z. Low Glucose plus β-Hydroxybutyrate Induces an Enhanced Inflammatory Response in Yak Alveolar Macrophages via Activating the GPR109A/NF-κB Signaling Pathway. Int J Mol Sci 2023; 24:11331. [PMID: 37511091 PMCID: PMC10379377 DOI: 10.3390/ijms241411331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 06/29/2023] [Accepted: 07/06/2023] [Indexed: 07/30/2023] Open
Abstract
Yaks are often subject to long-term starvation and a high prevalence of respiratory diseases and mortality in the withered season, yet the mechanisms that cause this remain unclear. Research has demonstrated that β-hydroxybutyrate (BHB) plays a significant role in regulating the immune system. Hence, we hypothesize that the low glucose and high BHB condition induced by severe starvation might have an effect on the pro-inflammatory response of the alveolar macrophages (AMs) in yaks. To validate our hypothesis, we isolated and identified primary AMs from freshly slaughtered yaks and cultured them in a medium with 5.5 mM of glucose or 2.8 mM of glucose plus 1-4 mM of BHB. Utilizing a real-time quantitative polymerase chain reaction (RT-qPCR), immunoblot assay, and enzyme-linked immunosorbent assay (ELISA), we evaluated the gene and protein expression levels of GPR109A (G-protein-coupled receptor 109A), NF-κB p65, p38, and PPARγ and the concentrations of pro-inflammatory cytokines interleukin (IL)-1β and IL-6 and tumor necrosis factor (TNF)-α in the supernatant. The results demonstrated that AMs exposed to low glucose plus BHB had significantly higher levels of IL-1β, IL-6, and TNF-α (p < 0.05) and higher activity of the GPR109A/NF-κB signaling pathway. A pretreatment of either pertussis toxin (PTX, inhibitor of GPR109A) or pyrrolidinedithiocarbamic (PDTC, inhibitor of NF-κB p65) was effective in preventing the elevated secretion of pro-inflammatory cytokines induced by low glucose plus BHB (p < 0.05). These results indicated that the low glucose plus BHB condition would induce an enhanced pro-inflammatory response through the activation of the GPR109A/NF-κB signaling pathway in primary yak AMs, which is probably the reason why yaks experience a higher rate of respiratory diseases and mortality. This study will offer new insight into the prevention and treatment of bovine respiratory diseases.
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Affiliation(s)
- Jiancheng Qi
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Qiyuan Yang
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Qing Xia
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Fangyuan Huang
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Hongrui Guo
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Hengmin Cui
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Yue Xie
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Zhihua Ren
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Liping Gou
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Dongjie Cai
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Maqsood Ahmed Kumbhar
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Jing Fang
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Zhicai Zuo
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
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10
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Duncan EM, Vita L, Dibnah B, Hudson BD. Metabolite-sensing GPCRs controlling interactions between adipose tissue and inflammation. Front Endocrinol (Lausanne) 2023; 14:1197102. [PMID: 37484963 PMCID: PMC10357040 DOI: 10.3389/fendo.2023.1197102] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 06/13/2023] [Indexed: 07/25/2023] Open
Abstract
Metabolic disorders including obesity, diabetes and non-alcoholic steatohepatitis are a group of conditions characterised by chronic low-grade inflammation of metabolic tissues. There is now a growing appreciation that various metabolites released from adipose tissue serve as key signalling mediators, influencing this interaction with inflammation. G protein-coupled receptors (GPCRs) are the largest family of signal transduction proteins and most historically successful drug targets. The signalling pathways for several key adipose metabolites are mediated through GPCRs expressed both on the adipocytes themselves and on infiltrating macrophages. These include three main groups of GPCRs: the FFA4 receptor, which is activated by long chain free fatty acids; the HCA2 and HCA3 receptors, activated by hydroxy carboxylic acids; and the succinate receptor. Understanding the roles these metabolites and their receptors play in metabolic-immune interactions is critical to establishing how these GPCRs may be exploited for the treatment of metabolic disorders.
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11
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Zucoloto AZ, Schlechte J, Ignacio A, Thomson CA, Pyke S, Yu IL, Geuking MB, McCoy KD, Yipp BG, Gillrie MR, McDonald B. Vascular traffic control of neutrophil recruitment to the liver by microbiota-endothelium crosstalk. Cell Rep 2023; 42:112507. [PMID: 37195866 DOI: 10.1016/j.celrep.2023.112507] [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: 11/21/2022] [Revised: 03/20/2023] [Accepted: 04/28/2023] [Indexed: 05/19/2023] Open
Abstract
During bloodstream infections, neutrophils home to the liver as part of an intravascular immune response to eradicate blood-borne pathogens, but the mechanisms regulating this crucial response are unknown. Using in vivo imaging of neutrophil trafficking in germ-free and gnotobiotic mice, we demonstrate that the intestinal microbiota guides neutrophil homing to the liver in response to infection mediated by the microbial metabolite D-lactate. Commensal-derived D-lactate augments neutrophil adhesion in the liver independent of granulopoiesis in bone marrow or neutrophil maturation and activation in blood. Instead, gut-to-liver D-lactate signaling primes liver endothelial cells to upregulate adhesion molecule expression in response to infection and promote neutrophil adherence. Targeted correction of microbiota D-lactate production in a model of antibiotic-induced dysbiosis restores neutrophil homing to the liver and reduces bacteremia in a model of Staphylococcus aureus infection. These findings reveal long-distance traffic control of neutrophil recruitment to the liver by microbiota-endothelium crosstalk.
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Affiliation(s)
- Amanda Z Zucoloto
- Department of Critical Care Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Jared Schlechte
- Department of Critical Care Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Aline Ignacio
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Carolyn A Thomson
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Shannon Pyke
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Ian-Ling Yu
- Department of Critical Care Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Markus B Geuking
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Microbiology, Immunology, and Infectious Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Kathy D McCoy
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Bryan G Yipp
- Department of Critical Care Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Mark R Gillrie
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Microbiology, Immunology, and Infectious Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Braedon McDonald
- Department of Critical Care Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
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12
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Wagner W, Sobierajska K, Pułaski Ł, Stasiak A, Ciszewski WM. Whole grain metabolite 3,5-dihydroxybenzoic acid is a beneficial nutritional molecule with the feature of a double-edged sword in human health: a critical review and dietary considerations. Crit Rev Food Sci Nutr 2023; 64:8786-8804. [PMID: 37096487 DOI: 10.1080/10408398.2023.2203762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2023]
Abstract
Nonprocessed foodstuffs of plant origin, especially whole-grain cereals, are considered to be health-promoting components of the human diet. While most of their well-studied effects derive from their high fiber content and low glycemic index, the presence of underrated phenolic phytonutrients has recently been brought to the attention of nutritionists. In this review, we report and discuss findings on the sources and bioactivities of 3,5-dihydroxybenzoic acid (3,5-DHBA), which is both a direct dietary component (found, e.g., in apples) and, more importantly, a crucial metabolite of whole-grain cereal-derived alkylresorcinols (ARs). 3,5-DHBA is a recently described exogenous agonist of the HCAR1/GPR81 receptor. We concentrate on the HCAR1-mediated effects of 3,5-DHBA in the nervous system, on the maintenance of cell stemness, regulation of carcinogenesis, and response to anticancer therapy. Unexpectedly, malignant tumors take advantage of HCAR1 expression to sense 3,5-DHBA to support their growth. Thus, there is an urgent need to fully identify the role of whole-grain-derived 3,5-DHBA during anticancer therapy and its contribution in the regulation of vital organs of the body via its specific HCAR1 receptor. We discuss here in detail the possible consequences of the modulatory capabilities of 3,5-DHBA in physiological and pathological conditions in humans.
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Affiliation(s)
- Waldemar Wagner
- Laboratory of Cellular Immunology, Institute of Medical Biology, Polish Academy of Sciences, Lodz, Poland
| | | | - Łukasz Pułaski
- Department of Oncobiology and Epigenetics, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
- Laboratory of Transcriptional Regulation, Institute of Medical Biology, Polish Academy of Sciences, Lodz, Poland
| | - Anna Stasiak
- Department of Hormone Biochemistry, Medical University of Lodz, Lodz, Poland
| | - Wojciech M Ciszewski
- Department of Molecular Cell Mechanisms, Medical University of Lodz, Lodz, Poland
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13
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Cai M, Wang H, Song H, Yang R, Wang L, Xue X, Sun W, Hu J. Lactate Is Answerable for Brain Function and Treating Brain Diseases: Energy Substrates and Signal Molecule. Front Nutr 2022; 9:800901. [PMID: 35571940 PMCID: PMC9099001 DOI: 10.3389/fnut.2022.800901] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Accepted: 03/18/2022] [Indexed: 11/13/2022] Open
Abstract
Research to date has provided novel insights into lactate's positive role in multiple brain functions and several brain diseases. Although notable controversies and discrepancies remain, the neurobiological role and the metabolic mechanisms of brain lactate have now been described. A theoretical framework on the relevance between lactate and brain function and brain diseases is presented. This review begins with the source and route of lactate formation in the brain and food; goes on to uncover the regulatory effect of lactate on brain function; and progresses to gathering the application and concentration variation of lactate in several brain diseases (diabetic encephalopathy, Alzheimer's disease, stroke, traumatic brain injury, and epilepsy) treatment. Finally, the dual role of lactate in the brain is discussed. This review highlights the biological effect of lactate, especially L-lactate, in brain function and disease studies and amplifies our understanding of past research.
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Affiliation(s)
- Ming Cai
- Department of Rehabilitation Medicine, Shanghai University of Medicine and Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
- Bio-X Institutes, Shanghai Jiao Tong University, Shanghai, China
| | - Hongbiao Wang
- Department of Physical Education, Shanghai University of Medicine and Health Sciences, Shanghai, China
| | - Haihan Song
- Central Lab, Shanghai Pudong New Area People's Hospital, Shanghai, China
| | - Ruoyu Yang
- College of Rehabilitation Sciences, Shanghai University of Medicine and Health Sciences, Shanghai, China
| | - Liyan Wang
- College of Rehabilitation Sciences, Shanghai University of Medicine and Health Sciences, Shanghai, China
| | - Xiangli Xue
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
| | - Wanju Sun
- Central Lab, Shanghai Pudong New Area People's Hospital, Shanghai, China
- *Correspondence: Wanju Sun
| | - Jingyun Hu
- Central Lab, Shanghai Pudong New Area People's Hospital, Shanghai, China
- Jingyun Hu
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14
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Crouse WL, Das SK, Le T, Keele G, Holl K, Seshie O, Craddock A, Sharma NK, Comeau ME, Langefeld C, Hawkins GA, Mott R, Valdar W, Solberg Woods LC. Transcriptome-wide analyses of adipose tissue in outbred rats reveal genetic regulatory mechanisms relevant for human obesity. Physiol Genomics 2022; 54:206-219. [PMID: 35467982 DOI: 10.1152/physiolgenomics.00172.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Transcriptomic analysis in metabolically active tissues allows a systems genetics approach to identify causal genes and networks involved in metabolic disease. Outbred heterogeneous stock (HS) rats are used for genetic mapping of complex traits, but to-date, a systems genetics analysis of metabolic tissues has not been done. We investigated whether adiposity-associated genes and gene co-expression networks in outbred heterogeneous stock (HS) rats overlap those found in humans. We analyzed RNAseq data from adipose tissue of 415 male HS rats, correlated these transcripts with body weight (BW) and compared transcriptome signatures to two human cohorts: the "African American Genetics of Metabolism and Expression" and "Metabolic Syndrome in Men". We used weighted gene co-expression network analysis to identify adiposity-associated gene networks and mediation analysis to identify genes under genetic control whose expression drives adiposity. We identified 554 orthologous "consensus genes" whose expression correlates with BW in the rat and with body mass index (BMI) in both human cohorts. Consensus genes fell within eight co-expressed networks and were enriched for genes involved in immune system function, cell growth, extracellular matrix organization and lipid metabolic processes. We identified 19 consensus genes for which genetic variation may influence BW via their expression, including those involved in lipolysis (e.g., Hcar1), inflammation (e.g., Rgs1), adipogenesis (e.g., Tmem120b) or no previously known role in obesity (e.g., St14, Msa4a6). Strong concordance between HS rat and human BW/BMI associated transcripts demonstrates translational utility of the rat model, while identification of novel genes expands our knowledge of the genetics underlying obesity.
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Affiliation(s)
- Wesley L Crouse
- University of North Carolina at Chapel Hill, Department of Genetics, Chapel Hill, NC, United States
| | - Swapan Kumar Das
- Wake Forest University School of Medicine, Department of Internal Medicine, Winston Salem, NC, United States
| | - Thu Le
- University College London, Department of Genetics, Evolution and Environment, Division of Biosciences, London, United Kingdom
| | - Gregory Keele
- Jackson Laboratories, Roux Center for Genomics and Computational Biology, Bar Harbor, ME, United States
| | - Katie Holl
- Medical College of Wisconsin, Department of Pediatrics, Milwaukee, WI, United States
| | - Osborne Seshie
- Wake Forest University School of Medicine, Department of Internal Medicine, Winston Salem, NC, United States
| | - Ann Craddock
- Wake Forest University School of Medicine, Department of Biochemistry, Winston Salem, NC, United States
| | - Neeraj Kumar Sharma
- Wake Forest University School of Medicine, Department of Internal Medicine, Winston Salem, NC, United States
| | - Mary Elizabeth Comeau
- Wake Forest University School of Medicine, Department of Biostatistics and Data Sciences, Winston Salem, NC, United States
| | - Carl Langefeld
- Wake Forest University School of Medicine, Department of Biostatistics and Data Sciences, Winston Salem, NC, United States
| | - Gregory A Hawkins
- Wake Forest University School of Medicine, Department of Biochemistry, Winston Salem, NC, United States
| | - Richard Mott
- University College London, Department of Genetics, Evolution and Environment, Division of Biosciences, London, United Kingdom
| | - William Valdar
- University of North Carolina at Chapel Hill, Department of Genetics, Chapel Hill, NC, United States
| | - Leah C Solberg Woods
- Wake Forest University School of Medicine, Department of Internal Medicine, Winston Salem, NC, United States
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15
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Wu G, Dai Y, Yan Y, Zheng X, Zhang H, Li H, Chen W. The lactate receptor GPR81 mediates hepatic lipid metabolism and the therapeutic effect of metformin on experimental NAFLDs. Eur J Pharmacol 2022; 924:174959. [PMID: 35430208 DOI: 10.1016/j.ejphar.2022.174959] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 04/11/2022] [Accepted: 04/12/2022] [Indexed: 01/06/2023]
Abstract
The lactate receptor G protein-coupled receptor 81 (GPR81) has been recently implicated in lipolysis in adipose tissue. In this study, we accidently discovered the role of GPR81 in hepatic lipid metabolism. Data clearly showed that hepatic GPR81 was markedly up-regulated in fasted mice, whereas it was severely down-regulated in obese mice. Genetic deficiency of GPR81 impaired ketogenic response, enhanced hepatic lipid accumulation, and exacerbated hepatosteatosis under acute fasting conditions. Mechanically, we demonstrated that hepatic GPR81 might function as a modulator of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), activate the downsream transcription of liver carnitine o-palmitoyltransferase 1(L-CPT1), and thereby control the influx of fatty acids into mitochondria for β-oxidation. Importantly, metformin improved experimental nonalcoholic fatty liver disease (NAFLDs) in a GPR81-dependent manner. Collectively, GPR81 was critical for hepatic lipid homeostasis and activation of hepatic GPR81 might represent a promising strategy for the treatment of obesity and its associated metabolic disorders.
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Affiliation(s)
- Guanglu Wu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Yufeng Dai
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Yongheng Yan
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Xu Zheng
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Hao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Haitao Li
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China.
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu, 214122, China
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16
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Mitophagy Mediates the Beige to White Transition of Human Primary Subcutaneous Adipocytes Ex Vivo. Pharmaceuticals (Basel) 2022; 15:ph15030363. [PMID: 35337160 PMCID: PMC8948887 DOI: 10.3390/ph15030363] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/11/2022] [Accepted: 03/14/2022] [Indexed: 12/12/2022] Open
Abstract
Brown and beige adipocytes have multilocular lipid droplets, express uncoupling protein (UCP) 1, and promote energy expenditure. In rodents, when the stimulus of browning subsides, parkin-dependent mitophagy is activated and dormant beige adipocytes persist. In humans, however, the molecular events during the beige to white transition have not been studied in detail. In this study, human primary subcutaneous abdominal preadipocytes were differentiated to beige for 14 days, then either the beige culture conditions were applied for an additional 14 days or it was replaced by a white medium. Control white adipocytes were differentiated by their specific cocktail for 28 days. Peroxisome proliferator-activated receptor γ-driven beige differentiation resulted in increased mitochondrial biogenesis, UCP1 expression, fragmentation, and respiration as compared to white. Morphology, UCP1 content, mitochondrial fragmentation, and basal respiration of the adipocytes that underwent transition, along with the induction of mitophagy, were similar to control white adipocytes. However, white converted beige adipocytes had a stronger responsiveness to dibutyril-cAMP, which mimics adrenergic stimulus, than the control white ones. Gene expression patterns showed that the removal of mitochondria in transitioning adipocytes may involve both parkin-dependent and -independent pathways. Preventing the entry of beige adipocytes into white transition can be a feasible way to maintain elevated thermogenesis and energy expenditure.
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17
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Nuclear Receptors in Energy Metabolism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1390:61-82. [DOI: 10.1007/978-3-031-11836-4_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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18
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Strassheim D, Sullivan T, Irwin DC, Gerasimovskaya E, Lahm T, Klemm DJ, Dempsey EC, Stenmark KR, Karoor V. Metabolite G-Protein Coupled Receptors in Cardio-Metabolic Diseases. Cells 2021; 10:3347. [PMID: 34943862 PMCID: PMC8699532 DOI: 10.3390/cells10123347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 11/10/2021] [Accepted: 11/18/2021] [Indexed: 12/15/2022] Open
Abstract
G protein-coupled receptors (GPCRs) have originally been described as a family of receptors activated by hormones, neurotransmitters, and other mediators. However, in recent years GPCRs have shown to bind endogenous metabolites, which serve functions other than as signaling mediators. These receptors respond to fatty acids, mono- and disaccharides, amino acids, or various intermediates and products of metabolism, including ketone bodies, lactate, succinate, or bile acids. Given that many of these metabolic processes are dysregulated under pathological conditions, including diabetes, dyslipidemia, and obesity, receptors of endogenous metabolites have also been recognized as potential drug targets to prevent and/or treat metabolic and cardiovascular diseases. This review describes G protein-coupled receptors activated by endogenous metabolites and summarizes their physiological, pathophysiological, and potential pharmacological roles.
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Affiliation(s)
- Derek Strassheim
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
| | - Timothy Sullivan
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
| | - David C. Irwin
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
| | - Evgenia Gerasimovskaya
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
| | - Tim Lahm
- Division of Pulmonary, Critical Care and Sleep Medicine, National Jewish Health Denver, Denver, CO 80206, USA;
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA
| | - Dwight J. Klemm
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA
- Division of Pulmonary Sciences and Critical Care Medicine, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Edward C. Dempsey
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA
- Division of Pulmonary Sciences and Critical Care Medicine, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Kurt R. Stenmark
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
| | - Vijaya Karoor
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
- Division of Pulmonary, Critical Care and Sleep Medicine, National Jewish Health Denver, Denver, CO 80206, USA;
- Division of Pulmonary Sciences and Critical Care Medicine, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
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19
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Manoharan I, Prasad PD, Thangaraju M, Manicassamy S. Lactate-Dependent Regulation of Immune Responses by Dendritic Cells and Macrophages. Front Immunol 2021; 12:691134. [PMID: 34394085 PMCID: PMC8358770 DOI: 10.3389/fimmu.2021.691134] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 07/14/2021] [Indexed: 12/28/2022] Open
Abstract
For decades, lactate has been considered an innocuous bystander metabolite of cellular metabolism. However, emerging studies show that lactate acts as a complex immunomodulatory molecule that controls innate and adaptive immune cells’ effector functions. Thus, recent advances point to lactate as an essential and novel signaling molecule that shapes innate and adaptive immune responses in the intestine and systemic sites. Here, we review these recent advances in the context of the pleiotropic effects of lactate in regulating diverse functions of immune cells in the tissue microenvironment and under pathological conditions.
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Affiliation(s)
- Indumathi Manoharan
- Georgia Cancer Center, Medical College of Georgia, Augusta University, Augusta, GA, United States.,Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Puttur D Prasad
- Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Muthusamy Thangaraju
- Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Santhakumar Manicassamy
- Georgia Cancer Center, Medical College of Georgia, Augusta University, Augusta, GA, United States.,Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta University, Augusta, GA, United States.,Department of Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States
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20
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Iannotti FA, Vitale RM. The Endocannabinoid System and PPARs: Focus on Their Signalling Crosstalk, Action and Transcriptional Regulation. Cells 2021; 10:586. [PMID: 33799988 PMCID: PMC8001692 DOI: 10.3390/cells10030586] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 02/26/2021] [Accepted: 03/03/2021] [Indexed: 02/06/2023] Open
Abstract
Peroxisome proliferator-activated receptors (PPARs) are a family of nuclear receptors including PPARα, PPARγ, and PPARβ/δ, acting as transcription factors to regulate the expression of a plethora of target genes involved in metabolism, immune reaction, cell differentiation, and a variety of other cellular changes and adaptive responses. PPARs are activated by a large number of both endogenous and exogenous lipid molecules, including phyto- and endo-cannabinoids, as well as endocannabinoid-like compounds. In this view, they can be considered an extension of the endocannabinoid system. Besides being directly activated by cannabinoids, PPARs are also indirectly modulated by receptors and enzymes regulating the activity and metabolism of endocannabinoids, and, vice versa, the expression of these receptors and enzymes may be regulated by PPARs. In this review, we provide an overview of the crosstalk between cannabinoids and PPARs, and the importance of their reciprocal regulation and modulation by common ligands, including those belonging to the extended endocannabinoid system (or "endocannabinoidome") in the control of major physiological and pathophysiological functions.
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Affiliation(s)
- Fabio Arturo Iannotti
- Institute of Biomolecular Chemistry, National Research Council (ICB-CNR), Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy
| | - Rosa Maria Vitale
- Institute of Biomolecular Chemistry, National Research Council (ICB-CNR), Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy
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21
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Kiran D, Basaraba RJ. Lactate Metabolism and Signaling in Tuberculosis and Cancer: A Comparative Review. Front Cell Infect Microbiol 2021; 11:624607. [PMID: 33718271 PMCID: PMC7952876 DOI: 10.3389/fcimb.2021.624607] [Citation(s) in RCA: 18] [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: 10/31/2020] [Accepted: 01/13/2021] [Indexed: 12/16/2022] Open
Abstract
Infection with Mycobacterium tuberculosis (Mtb) leading to tuberculosis (TB) disease continues to be a major global health challenge. Critical barriers, including but not limited to the development of multi-drug resistance, lack of diagnostic assays that detect patients with latent TB, an effective vaccine that prevents Mtb infection, and infectious and non-infectious comorbidities that complicate active TB, continue to hinder progress toward a TB cure. To complement the ongoing development of new antimicrobial drugs, investigators in the field are exploring the value of host-directed therapies (HDTs). This therapeutic strategy targets the host, rather than Mtb, and is intended to augment host responses to infection such that the host is better equipped to prevent or clear infection and resolve chronic inflammation. Metabolic pathways of immune cells have been identified as promising HDT targets as more metabolites and metabolic pathways have shown to play a role in TB pathogenesis and disease progression. Specifically, this review highlights the potential role of lactate as both an immunomodulatory metabolite and a potentially important signaling molecule during the host response to Mtb infection. While long thought to be an inert end product of primarily glucose metabolism, the cancer research field has discovered the importance of lactate in carcinogenesis and resistance to chemotherapeutic drug treatment. Herein, we discuss similarities between the TB granuloma and tumor microenvironments in the context of lactate metabolism and identify key metabolic and signaling pathways that have been shown to play a role in tumor progression but have yet to be explored within the context of TB. Ultimately, lactate metabolism and signaling could be viable HDT targets for TB; however, critical additional research is needed to better understand the role of lactate at the host-pathogen interface during Mtb infection before adopting this HDT strategy.
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Affiliation(s)
| | - Randall J. Basaraba
- Metabolism of Infectious Diseases Laboratory, Mycobacteria Research Laboratories, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States
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22
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Yao Z, Yan Y, Zheng X, Wang M, Zhang H, Li H, Chen W. Dietary Lactate Supplementation Protects against Obesity by Promoting Adipose Browning in Mice. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:14841-14849. [PMID: 33284607 DOI: 10.1021/acs.jafc.0c05899] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Yogurt has been widely used in weight-loss foods to prevent obesity, but its molecular nature remains unclear. Lactate is a major ingredient of yogurt, while its cognate cell surface receptor GPR81 is highly expressed in adipose tissues in mammals. Here we hypothesized that dietary lactate supplementation might activate GPR81 to promote adipose browning. Studying mouse models, we observed that GPR81 was substantially lowered in adipose tissue of obese mice compared with that for lean ones, whereas its expression was markedly up-regulated by a β3-adrenergic receptor (β3-AR) agonist. The deficiency of GPR81 greatly attenuated experimental adipose browning and thermogenesis. Importantly, oral administration of lactate effectively induced adipose browning, enhanced thermogenesis, improved dyslipidemia, and protected mice against high-fat-diet-induced obesity. Mechanistically, p38 mitogen-activated protein kinase might serve as a key downstream effect or of GPR81. Collectively, our findings revealed a critical role of GPR81 in adipose browning and provided a new insight into obesity management by modulating lactate-GPR81 signaling axis.
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MESH Headings
- Adipose Tissue, Brown/drug effects
- Adipose Tissue, Brown/metabolism
- Animals
- Dietary Supplements/analysis
- Energy Metabolism/drug effects
- Humans
- Lactic Acid/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Obese
- Obesity/drug therapy
- Obesity/genetics
- Obesity/metabolism
- Obesity/physiopathology
- Protective Agents/administration & dosage
- Receptors, Adrenergic, beta-3/genetics
- Receptors, Adrenergic, beta-3/metabolism
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
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Affiliation(s)
- Zhijie Yao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Yongheng Yan
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Xu Zheng
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Mingfu Wang
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - Hao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Haitao Li
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu 214122, China
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23
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Immunoreactivity of receptor and transporters for lactate located in astrocytes and epithelial cells of choroid plexus of human brain. Neurosci Lett 2020; 741:135479. [PMID: 33212210 DOI: 10.1016/j.neulet.2020.135479] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/19/2020] [Accepted: 10/30/2020] [Indexed: 11/20/2022]
Abstract
Glucose metabolism produces lactate and hydrogen ions in an anaerobic environment. Cerebral ischemia or hypoxia is believed to become progressively lactacidemic. Monocarboxylate transporters (MCTs) in endothelial cells are essential for the transport of lactate from the blood into the brain. In addition, it is considered that MCTs located in astrocytic and neuronal cells play a key role in the shuttling of energy metabolites between neurons and astrocytes. However, roles of lactate in the brain remain to be clarified. In this study, the localization of lactate transporters and a receptor for cellular uptake of lactate was immunohistochemically examined in autopsied human brains. Immunoreactivity for MCT1 was observed in the apical cytoplasmic membrane of some epithelial cells in the choroid plexus as well as astrocytes and the capillary wall, whereas that for MCT4 was found in the basolateral cytoplasmic membrane of small number of epithelial cells as well as astrocytes and the capillary wall. In addition, immunoreactivity for the hydroxy-carboxylic acid 1 receptor (HCA1 receptor), a receptor for cellular uptake of lactate, was also found on the basolateral cytoplasmic membrane of epithelial cells as well as astrocytic and neuronal cells. Immunoreactivity for lactate dehydrogenase (LDH)-B was observed in the cytoplasm of epithelial cells in the choroid plexus as well as astrocytes and the capillary wall. These immunohistochemical findings indicate the localization of MCT1, MCT4, the HCA1 receptor, and LDH-B in epithelial cells of the choroid plexus as well as astrocytes, and suggest the transport of intravascular lactate into the brain through epithelial cells of the choroid plexus as well as cerebral vessels and the possibility of lactate being utilized in epithelial cells.
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24
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Griffin MD, Pereira SR, DeBari MK, Abbott RD. Mechanisms of action, chemical characteristics, and model systems of obesogens. BMC Biomed Eng 2020; 2:6. [PMID: 32903358 PMCID: PMC7422567 DOI: 10.1186/s42490-020-00040-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 04/07/2020] [Indexed: 02/06/2023] Open
Abstract
There is increasing evidence for the role of environmental endocrine disrupting contaminants, coined obesogens, in exacerbating the rising obesity epidemic. Obesogens can be found in everyday items ranging from pesticides to food packaging. Although research shows that obesogens can have effects on adipocyte size, phenotype, metabolic activity, and hormone levels, much remains unknown about these chemicals. This review will discuss what is currently known about the mechanisms of obesogens, including expression of the PPARs, hormone interference, and inflammation. Strategies for identifying obesogenic chemicals and their mechanisms through chemical characteristics and model systems will also be discussed. Ultimately, research should focus on improving models to discern precise mechanisms of obesogenic action and to test therapeutics targeting these mechanisms.
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Affiliation(s)
- Mallory D Griffin
- Carnegie Mellon University, 5000 Forbes Avenue, Scott Hall, Pittsburgh, PA 15213 USA
| | - Sean R Pereira
- Carnegie Mellon University, 5000 Forbes Avenue, Scott Hall, Pittsburgh, PA 15213 USA
| | - Megan K DeBari
- Carnegie Mellon University, 5000 Forbes Avenue, Scott Hall, Pittsburgh, PA 15213 USA
| | - Rosalyn D Abbott
- Carnegie Mellon University, 5000 Forbes Avenue, Scott Hall, Pittsburgh, PA 15213 USA
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25
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Hu J, Cai M, Liu Y, Liu B, Xue X, Ji R, Bian X, Lou S. The roles of GRP81 as a metabolic sensor and inflammatory mediator. J Cell Physiol 2020; 235:8938-8950. [PMID: 32342523 DOI: 10.1002/jcp.29739] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Revised: 04/09/2020] [Accepted: 04/16/2020] [Indexed: 12/31/2022]
Abstract
GPR81 (also named as HCA1) is a member of a subfamily of orphan G-protein coupled receptors (GPCRs), coupled to Gi -type G proteins. GPR81 was discovered in 2001 and identified as the only known endogenous receptor of lactate under physiological conditions in 2008, which opened a new field of research on how lactate may act as a signal molecule along with the GPR81 expression in the roles of metabolic process and inflammatory response. Recent studies showed that the physiological functions of GPR81 include lipid metabolism in adipose tissues, metabolic excitability in the brain, cellular development, and inflammatory response modulation. These findings may reveal a novel therapeutic strategy to treat clinical, metabolic, and inflammatory diseases. This article will summarize past research on GPR81, including its characteristics of distribution and expression, functional residues, pharmacological, and physiological agonists, involvement in signal transduction, and pharmacological applications.
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Affiliation(s)
- Jingyun Hu
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
| | - Ming Cai
- College of Rehabilitation Sciences, Shanghai University of Medicine & Health Sciences, Shanghai, China
| | - Yuran Liu
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
| | - Beibei Liu
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China.,Department of Clinical Medicine, Weifang Medical College, Weifang, Shandong, China
| | - Xiangli Xue
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
| | - Ruifang Ji
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
| | - Xuepeng Bian
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
| | - Shujie Lou
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
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26
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Xie Q, Zhu Z, He Y, Zhang Z, Zhang Y, Wang Y, Luo J, Peng T, Cheng F, Gao J, Cao Y, Wei H, Wu Z. A lactate-induced Snail/STAT3 pathway drives GPR81 expression in lung cancer cells. Biochim Biophys Acta Mol Basis Dis 2019; 1866:165576. [PMID: 31666207 DOI: 10.1016/j.bbadis.2019.165576] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 09/13/2019] [Accepted: 09/30/2019] [Indexed: 02/03/2023]
Abstract
Highly expressed G protein-coupled receptor 81 (GPR81), a receptor for lactate, is emerging as a critical regulator of tumor growth and metastasis. However, the mechanistic basis for its highly expression in cancer cells remains elusive. Here we report that tumor-derived lactate transcriptionally regulates GPR81 expression. We demonstrated that the transcriptional response of GPR81 to lactate is mediated by Signal transducer and activator of transcription 3 (STAT3). Mechanistically, lactate upregulates transcriptional factor Snail and induces the assembly of Snail/EZH2/STAT3 complex. Within this ternary complex, STAT3 activity is strongly enhanced. Consequently, the activated STAT3 by lactate directly binds GPR81promoter and activates its expression. These findings shed light on the transcriptional mechanism by which GPR81 expression is regulated in cancer cells, and provides mechanistic insight into how aberrant signaling and continually high lactate levels due to metabolic switch may yield a feed-forward/self-enabling loop to promote tumor progression.
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Affiliation(s)
- Qiang Xie
- Research laboratory of Tumor Microenvironment, Wannan Medical College, Wuhu 241001, China; School of pharmacy, Wannan Medical College, Wuhu 241001, China; Key Laboratory of Non-coding RNA Transformation Research of Anhui Higher Education Institution, Wannan Medical College, Wuhu 241001, China
| | - Zhanzhan Zhu
- Research laboratory of Tumor Microenvironment, Wannan Medical College, Wuhu 241001, China; School of pharmacy, Wannan Medical College, Wuhu 241001, China; Key Laboratory of Non-coding RNA Transformation Research of Anhui Higher Education Institution, Wannan Medical College, Wuhu 241001, China
| | - Yuanpeng He
- Research laboratory of Tumor Microenvironment, Wannan Medical College, Wuhu 241001, China; School of Clinical Medicine, Wannan Medical College, Wuhu 241001, China
| | - Zhijian Zhang
- Research laboratory of Tumor Microenvironment, Wannan Medical College, Wuhu 241001, China; School of Preclinical Medicine, Wannan Medical College, Wuhu 241001, China
| | - Yao Zhang
- Anhui Province Key laboratory of Active Biological Macro-molecules Research, Wannan Medical College, Wuhu 241001, China
| | - Yixuan Wang
- School of Clinical Medicine, Wannan Medical College, Wuhu 241001, China
| | - Jincheng Luo
- Research laboratory of Tumor Microenvironment, Wannan Medical College, Wuhu 241001, China; School of Clinical Medicine, Wannan Medical College, Wuhu 241001, China
| | - Tianchou Peng
- Research laboratory of Tumor Microenvironment, Wannan Medical College, Wuhu 241001, China; School of Clinical Medicine, Wannan Medical College, Wuhu 241001, China
| | - Feng Cheng
- Research laboratory of Tumor Microenvironment, Wannan Medical College, Wuhu 241001, China; Anhui Province Key laboratory of Active Biological Macro-molecules Research, Wannan Medical College, Wuhu 241001, China
| | - Jiguang Gao
- Research laboratory of Tumor Microenvironment, Wannan Medical College, Wuhu 241001, China; School of Preclinical Medicine, Wannan Medical College, Wuhu 241001, China; School of pharmacy, Wannan Medical College, Wuhu 241001, China
| | - Yuxiang Cao
- Research laboratory of Tumor Microenvironment, Wannan Medical College, Wuhu 241001, China; Anhui Province Key laboratory of Active Biological Macro-molecules Research, Wannan Medical College, Wuhu 241001, China
| | - Huijun Wei
- Research laboratory of Tumor Microenvironment, Wannan Medical College, Wuhu 241001, China; Anhui Province Key laboratory of Active Biological Macro-molecules Research, Wannan Medical College, Wuhu 241001, China
| | - Zhihao Wu
- Research laboratory of Tumor Microenvironment, Wannan Medical College, Wuhu 241001, China; School of Preclinical Medicine, Wannan Medical College, Wuhu 241001, China; Anhui Province Key laboratory of Active Biological Macro-molecules Research, Wannan Medical College, Wuhu 241001, China.
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27
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Garcia-Flores AE, Sollome JJ, Thavathiru E, Bower JL, Vaillancourt RR. HER2/HER3 regulates lactate secretion and expression of lactate receptor mRNA through the MAP3K4 associated protein GIT1. Sci Rep 2019; 9:10823. [PMID: 31346208 PMCID: PMC6658559 DOI: 10.1038/s41598-019-46954-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 07/03/2019] [Indexed: 12/16/2022] Open
Abstract
One of the major features of cancer is Otto Warburg’s observation that many tumors have increased extracellular acidification compared to healthy tissues. Since Warburg’s observation, the importance of extracellular acidification in cancer is now considered a hallmark of cancer. Human MAP3K4 functions upstream of the p38 and JNK mitogen activated protein kinases (MAPKs). Additionally, MAP3K4 is required for cell migration and extracellular acidification of breast cancer cells in response to HER2/HER3 signaling. Here, we demonstrate that GIT1 interacts with MAP3K4 by immunoprecipitation, while cellular lactate production and the capacity of MCF-7 cells for anchorage independent growth in soft agar were dependent on GIT1. Additionally, we show that activation of HER2/HER3 signaling leads to reduced expression of lactate receptor (GPR81) mRNA and that both, GIT1 and MAP3K4, are necessary for constitutive expression of GPR81 mRNA. Our study suggests that targeting downstream proteins in the HER2/HER3-induced extracellular lactate signaling pathway may be a way to inhibit the Warburg Effect to disrupt tumor growth.
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Affiliation(s)
- Alejandro E Garcia-Flores
- The Department of Pharmacology and Toxicology, College of Pharmacy University of Arizona, Tucson, Arizona, 85721, USA
| | | | | | - Joseph L Bower
- University of Texas Southwestern Medical Center, Dallas, United States
| | - Richard R Vaillancourt
- The Department of Pharmacology and Toxicology, College of Pharmacy University of Arizona, Tucson, Arizona, 85721, USA.
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28
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Mandrika I, Tilgase A, Petrovska R, Klovins J. Hydroxycarboxylic Acid Receptor Ligands Modulate Proinflammatory Cytokine Expression in Human Macrophages and Adipocytes without Affecting Adipose Differentiation. Biol Pharm Bull 2019; 41:1574-1580. [PMID: 30270326 DOI: 10.1248/bpb.b18-00301] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Members of the hydroxycarboxylic acid receptor (HCA1-3) family are mainly expressed in adipocytes and immune cells. HCA2 ligand, niacin, has been used for decades as lipid-modifying drug. Recent studies suggest that HCA ligands can be involved in the modulation of inflammatory processes. In this study, we evaluated the effects of HCA1-3 ligands on adipose differentiation and cytokine expression in human adipocytes and macrophages. Simpson-Golabi-Behmel syndrome (SGBS) preadipocytes were induced to differentiate into adipocytes for 8 d in the presence or absence of HCA ligands and evaluated for lipid accumulation and adipogenic gene expression. The inhibitory effects of the ligands on the expression and production of cytokines were measured in lipopolysaccharide (LPS)-stimulated adipocytes and THP-1 macrophage cells. Preadipocytes treated with HCA ligands showed no changes in the capacity to differentiate into adipocytes and no significant alteration in peroxisome proliferator activated receptor γ (PPARγ) or its target gene expression. HCA2-3 ligands significantly downregulated LPS-induced expression of interleukin (IL)-6 (53-64%), tumor necrosis factor-α (TNF-α) (55-69%) and IL-8 (51-59%) in adipocytes and macrophages. IL-1β inhibition (58-68%) by HCA2-3 ligands was observed only in adipocytes. Furthermore, LPS increased the expression of HCA2-3 in adipocytes and macrophages and this expression was decreased by treatment with their ligands. These results suggest that HCA ligands modulated LPS-mediated pro-inflammatory gene expression in both macrophages and adipocytes without affecting adipogenesis. Therefore, targeting HCA2 and HCA3 would be beneficial in treating inflammation conditions associated with atherosclerosis and obesity.
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29
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Montastier E, Beuzelin D, Martins F, Mir L, Marqués MA, Thalamas C, Iacovoni J, Langin D, Viguerie N. Niacin induces miR-502-3p expression which impairs insulin sensitivity in human adipocytes. Int J Obes (Lond) 2018; 43:1485-1490. [PMID: 30482933 DOI: 10.1038/s41366-018-0260-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 09/14/2018] [Accepted: 09/27/2018] [Indexed: 01/14/2023]
Abstract
MicroRNAs have been involved in insulin resistance (IR). As the mechanism whereby niacin, an anti-dyslipidemic agent, leads to IR remains elusive, we sought to identify differentially expressed microRNAs in adipose tissue (AT) of individuals receiving niacin and to explore the link between microRNAs, niacin and IR in human adipocytes.In a double-blind controlled study, 22 obese men received extended-release niacin or placebo over 8 weeks. Bioclinical data and subcutaneous AT biopsies were obtained before and after treatment. AT microRNA expression profiles were determined using RTqPCR for 758 human-specific microRNAs. hMADS adipocytes were treated with niacin, or acipimox (a niacin-like drug without effect on IR), or transfected with miR-502-3p. Glucose uptake and Western blotting were performed.In obese men, insulin sensitivity decreased after niacin treatment. In AT, the expression of 6 microRNAs including miR-502-3p was up-regulated. Treatment of hMADS adipocytes with niacin specifically increased miR-502-3p expression. Acipimox had no effect. Overexpression of miR-502-3p in adipocytes led to reduced insulin-induced glucose uptake and lower insulin-stimulated AKT phosphorylation.Long term niacin treatment altered microRNA expression levels in human AT. Increased miR-502-3p expression may play a role in the mediation of IR due to niacin in adipocytes.The study is registered in Clinical Trials NCT01083329 and EudraCT 2009-012124-85.
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Affiliation(s)
- Emilie Montastier
- Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases (I2MC), Toulouse, France.,University of Toulouse, UMR1048, Paul Sabatier University, Toulouse, France.,Departments of Endocrinology, Toulouse University Hospitals, Metabolism and Nutrition, and Clinical Biochemistry, Toulouse, France
| | - Diane Beuzelin
- Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases (I2MC), Toulouse, France.,University of Toulouse, UMR1048, Paul Sabatier University, Toulouse, France
| | - Frédéric Martins
- Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases (I2MC), Toulouse, France.,Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1048, Plateforme GeT (Génome et Transcriptome) du Génopole, Toulouse, France
| | - Lucile Mir
- Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases (I2MC), Toulouse, France
| | - Marie-Adeline Marqués
- Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases (I2MC), Toulouse, France
| | - Claire Thalamas
- Institut National de la Santé et de la Recherche Médicale (Inserm), Clinical Investigation Center 1436, Toulouse, France.,Toulouse University Hospitals, Clinical Investigation Center 1436, Toulouse, France
| | - Jason Iacovoni
- Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases (I2MC), Toulouse, France
| | - Dominique Langin
- Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases (I2MC), Toulouse, France.,University of Toulouse, UMR1048, Paul Sabatier University, Toulouse, France.,Departments of Endocrinology, Toulouse University Hospitals, Metabolism and Nutrition, and Clinical Biochemistry, Toulouse, France
| | - Nathalie Viguerie
- Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases (I2MC), Toulouse, France. .,University of Toulouse, UMR1048, Paul Sabatier University, Toulouse, France.
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30
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Liu CP, Chau PC, Chang CT, An LM, Yeh JL, Chen IJ, Wu BN. KMUP-1, a GPCR Modulator, Attenuates Triglyceride Accumulation Involved MAPKs/Akt/PPARγ and PKA/PKG/HSL Signaling in 3T3-L1 Preadipocytes. Molecules 2018; 23:molecules23102433. [PMID: 30249030 PMCID: PMC6222827 DOI: 10.3390/molecules23102433] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 09/17/2018] [Accepted: 09/22/2018] [Indexed: 12/25/2022] Open
Abstract
Xanthine-based KMUP-1 was shown to inhibit phosphodiesterases (PDEs) and modulate G-protein coupled receptors (GPCRs) to lower hyperlipidemia and body weight. This study further investigated whether KMUP-1 affects adipogenesis and lipolysis in 3T3-L1 preadipocytes. KMUP-1 (1–40 µM) concentration-dependently attenuated Oil Red O (ORO) staining and decreased triglyceride (TG) accumulation, indicating adipogenesis inhibition in 3T3-L1 cells. In contrast, the β-agonist ractopamine increased ORO staining and TG accumulation and adipogenesis. KMUP-1 (1–40 µM) also reduced MAPKs/Akt/PPARγ expression, PPARγ1/PPARγ2 mRNA, and p-ERK immunoreactivity at the adipogenesis stage, but enhanced hormone sensitive lipase (HSL) immunoreactivity at the lipolysis stage. Addition of protein kinase A (PKA) or protein kinase G (PKG) antagonist (KT5720 or KT5728) to adipocytes did not affect HSL immunoreactivity. However, KMUP-1 did increase HSL immunoreactivity and the effect was reduced by PKA or PKG antagonist. Simvastatin, theophylline, caffeine, and sildenafil, like KMUP-1, also enhanced HSL immunoreactivity. Phosphorylated HSL (p-HSL) was enhanced by KMUP-1, indicating increased lipolysis in mature 3T3-L1 adipocytes. Decreases of MAPKs/Akt/PPARγ during adipogenesis contributed to inhibition of adipocyte differentiation, and increases of PKA/PKG at lipolysis contributed to HSL activation and TG hydrolysis. Taken together, the data suggest that KMUP-1 can inhibit hyperadiposity in 3T3-L1 adipocytes.
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Affiliation(s)
- Chung-Pin Liu
- Department of Cardiology, Yuan's General Hospital, Kaohsiung 802, Taiwan.
| | - Pei-Chun Chau
- Department of Pharmacology, Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
| | - Chain-Ting Chang
- Department of Pharmacology, Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
| | - Li-Mei An
- Department of Pharmacology, Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
| | - Jwu-Lai Yeh
- Department of Pharmacology, Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan.
| | - Ing-Jun Chen
- Department of Pharmacology, Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
- Department of Medical Education and Research, Pingtung Christian Hospital, Pingtung 900, Taiwan.
| | - Bin-Nan Wu
- Department of Pharmacology, Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan.
- Lipid Science and Aging Research Center, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
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Decreased expression of G-protein-coupled receptors GPR43 and GPR109a in psoriatic skin can be restored by topical application of sodium butyrate. Arch Dermatol Res 2018; 310:751-758. [PMID: 30209581 DOI: 10.1007/s00403-018-1865-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 09/04/2018] [Accepted: 09/08/2018] [Indexed: 12/27/2022]
Abstract
The G-protein-coupled receptors GPR43 and GPR109a are known to play an important role in mediating anti-inflammatory and anti-cancer functions in the gut. Short-chain fatty acids, such as sodium butyrate (SB), are activators of GPR43 and GPR109a and thereby promote anti-inflammatory effects. The present study aimed to examine the expression of these receptors and their reaction to SB in psoriasis. Lesional and non-lesional biopsies of 6 psoriasis patients and of 4 controls were obtained and stained for GPR109a and GPR43. Ex vivo stimulation with SB was performed on fresh biopsy material. Lesional and non-lesional psoriatic skin showed a decreased expression of GPR109a and GPR43 on keratinocytes in comparison with control skin. Topical application of SB was able to increase the low-level expression of both receptors. The data suggest that SB by restoring the impaired expression of GPR109a and GPR43 might exert anti-inflammatory effects and may be utilized as a topical tool for the treatment of psoriasis, which has to be proven in future clinical trials.
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Discovery of coumarin-dihydroquinazolinone analogs as niacin receptor 1 agonist with in-vivo anti-obesity efficacy. Eur J Med Chem 2018; 152:208-222. [DOI: 10.1016/j.ejmech.2018.04.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 04/05/2018] [Accepted: 04/18/2018] [Indexed: 11/21/2022]
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Zhao N, Li X, Feng Y, Han J, Feng Z, Li X, Wen Y. The Nuclear Orphan Receptor Nur77 Alleviates Palmitate-induced Fat Accumulation by Down-regulating G0S2 in HepG2 Cells. Sci Rep 2018; 8:4809. [PMID: 29556076 PMCID: PMC5859288 DOI: 10.1038/s41598-018-23141-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 03/07/2018] [Indexed: 12/11/2022] Open
Abstract
Excessive triglyceride accumulation in hepatocytes is the hallmark of obesity-associated nonalcoholic fatty liver disease (NAFLD). Elevated levels of the saturated free fatty acid palmitate in obesity are a major contributor to excessive hepatic lipid accumulation. The nuclear orphan receptor Nur77 is a transcriptional regulator and a lipotoxicity sensor. Using human HepG2 hepatoma cells, this study aimed to investigate the functional role of Nur77 in palmitate-induced hepatic steatosis. The results revealed that palmitate significantly induced lipid accumulation and suppressed lipolysis in hepatocytes. In addition, palmitate significantly suppressed Nur77 expression and stimulated the expression of peroxisome proliferator-activated receptor γ (PPARγ) and its target genes. Nur77 overexpression significantly reduced palmitate-induced expression of PPARγ and its target genes. Moreover, Nur77 overexpression attenuated lipid accumulation and augmented lipolysis in palmitate-treated hepatocytes. Importantly, G0S2 knockdown significantly attenuated lipid accumulation and augmented lipolysis in palmitate-treated hepatocytes, whereas G0S2 knockdown had no effect on the palmitate-induced expression of Nur77, PPARγ, or PPARγ target genes. In summary, palmitate suppresses Nur77 expression in HepG2 cells, and Nur77 overexpression alleviates palmitate-induced hepatic fat accumulation by down-regulating G0S2. These results display a novel molecular mechanism linking Nur77-regulated G0S2 expression to palmitate-induced hepatic steatosis.
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Affiliation(s)
- Naiqian Zhao
- Department of Gerontology, Second Hospital of Shanxi Medical University, 382 Wuyi Road, Taiyuan, 030001, Shanxi, China.
| | - Xiaoyan Li
- Department of Infectious Diseases, First People's Hospital of Jinzhong, 85 Shuncheng Street, Jinzhong, 030600, Shanxi, China
| | - Ying Feng
- Department of Gerontology, Second Hospital of Shanxi Medical University, 382 Wuyi Road, Taiyuan, 030001, Shanxi, China
| | - Jinxiang Han
- Department of Gerontology, Second Hospital of Shanxi Medical University, 382 Wuyi Road, Taiyuan, 030001, Shanxi, China
| | - Ziling Feng
- Department of Infectious Diseases, First People's Hospital of Jinzhong, 85 Shuncheng Street, Jinzhong, 030600, Shanxi, China
| | - Xifeng Li
- Department of Infectious Diseases, First People's Hospital of Jinzhong, 85 Shuncheng Street, Jinzhong, 030600, Shanxi, China
| | - Yanfang Wen
- Department of Infectious Diseases, First People's Hospital of Jinzhong, 85 Shuncheng Street, Jinzhong, 030600, Shanxi, China
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Ranganathan P, Shanmugam A, Swafford D, Suryawanshi A, Bhattacharjee P, Hussein MS, Koni PA, Prasad PD, Kurago ZB, Thangaraju M, Ganapathy V, Manicassamy S. GPR81, a Cell-Surface Receptor for Lactate, Regulates Intestinal Homeostasis and Protects Mice from Experimental Colitis. THE JOURNAL OF IMMUNOLOGY 2018; 200:1781-1789. [PMID: 29386257 DOI: 10.4049/jimmunol.1700604] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 12/18/2017] [Indexed: 01/29/2023]
Abstract
At mucosal sites such as the intestine, the immune system launches robust immunity against invading pathogens while maintaining a state of tolerance to commensal flora and ingested food Ags. The molecular mechanisms underlying this phenomenon remain poorly understood. In this study, we report that signaling by GPR81, a receptor for lactate, in colonic dendritic cells and macrophages plays an important role in suppressing colonic inflammation and restoring colonic homeostasis. Genetic deletion of GPR81 in mice led to increased Th1/Th17 cell differentiation and reduced regulatory T cell differentiation, resulting in enhanced susceptibility to colonic inflammation. This was due to increased production of proinflammatory cytokines (IL-6, IL-1β, and TNF-α) and decreased expression of immune regulatory factors (IL-10, retinoic acid, and IDO) by intestinal APCs lacking GPR81. Consistent with these findings, pharmacological activation of GPR81 decreased inflammatory cytokine expression and ameliorated colonic inflammation. Taken together, these findings identify a new and important role for the GPR81 signaling pathway in regulating immune tolerance and colonic inflammation. Thus, manipulation of the GPR81 pathway could provide novel opportunities for enhancing regulatory responses and treating colonic inflammation.
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Affiliation(s)
| | | | - Daniel Swafford
- Georgia Cancer Center, Augusta University, Augusta, GA 30912
| | | | - Pushpak Bhattacharjee
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430
| | | | - Pandelakis A Koni
- Georgia Cancer Center, Augusta University, Augusta, GA 30912.,Department of Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30901.,Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta University, Augusta, GA 30901; and
| | - Puttur D Prasad
- Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta University, Augusta, GA 30901; and
| | - Zoya B Kurago
- Dental College of Georgia, Augusta University, Augusta, GA 30912
| | - Muthusamy Thangaraju
- Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta University, Augusta, GA 30901; and
| | - Vadivel Ganapathy
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430
| | - Santhakumar Manicassamy
- Georgia Cancer Center, Augusta University, Augusta, GA 30912; .,Department of Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30901
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35
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Zhao NQ, Li XY, Wang L, Feng ZL, Li XF, Wen YF, Han JX. Palmitate induces fat accumulation by activating C/EBPβ-mediated G0S2 expression in HepG2 cells. World J Gastroenterol 2017; 23:7705-7715. [PMID: 29209111 PMCID: PMC5703930 DOI: 10.3748/wjg.v23.i43.7705] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 09/27/2017] [Accepted: 09/28/2017] [Indexed: 02/06/2023] Open
Abstract
AIM To determine the role of G0/G1 switch gene 2 (G0S2) and its transcriptional regulation in palmitate-induced hepatic lipid accumulation.
METHODS HepG2 cells were treated with palmitate, or palmitate in combination with CCAAT/enhancer binding protein (C/EBP)β siRNA or G0S2 siRNA. The mRNA expression of C/EBPβ, peroxisome proliferator-activated receptor (PPAR)γ and PPARγ target genes (G0S2, GPR81, GPR109A and Adipoq) was examined by qPCR. The protein expression of C/EBPβ, PPARγ, and G0S2 was determined by Western blotting. Lipid accumulation was detected with Oil Red O staining and quantified by absorbance value of the extracted Oil Red O dye. Lipolysis was evaluated by measuring the amount of glycerol released into the medium.
RESULTS Palmitate caused a dose-dependent increase in lipid accumulation and a dose-dependent decrease in lipolysis in HepG2 cells. In addition, palmitate increased the mRNA expression of C/EBPβ, PPARγ, and PPARγ target genes (G0S2, GPR81, GPR109A, and Adipoq) and the protein expression of C/EBPβ, PPARγ, and G0S2 in a dose-dependent manner. Knockdown of C/EBPβ decreased palmitate-induced PPARγ and its target genes (G0S2, GPR81, GPR109A, and Adipoq) mRNA expression and palmitate-induced PPARγ and G0S2 protein expression in HepG2 cells. Knockdown of C/EBPβ also attenuated lipid accumulation and augmented lipolysis in palmitate-treated HepG2 cells. G0S2 knockdown attenuated lipid accumulation and augmented lipolysis, while G0S2 knockdown had no effects on the mRNA expression of C/EBPβ, PPARγ, and PPARγ target genes (GPR81, GPR109A and Adipoq) in palmitate-treated HepG2 cells.
CONCLUSION Palmitate can induce lipid accumulation in HepG2 cells by activating C/EBPβ-mediated G0S2 expression.
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Affiliation(s)
- Nai-Qian Zhao
- Department of Gerontology, the Second Hospital of Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
| | - Xiao-Yan Li
- Department of Infectious Diseases, the First People’s Hospital of Jinzhong, Jinzhong 030600, Shanxi Province, China
| | - Li Wang
- Department of Gerontology, the Second Hospital of Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
| | - Zi-Ling Feng
- Department of Infectious Diseases, the First People’s Hospital of Jinzhong, Jinzhong 030600, Shanxi Province, China
| | - Xi-Fen Li
- Department of Infectious Diseases, the First People’s Hospital of Jinzhong, Jinzhong 030600, Shanxi Province, China
| | - Yan-Fang Wen
- Department of Infectious Diseases, the First People’s Hospital of Jinzhong, Jinzhong 030600, Shanxi Province, China
| | - Jin-Xiang Han
- Department of Gerontology, the Second Hospital of Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
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36
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Davidson MA, Mattison DR, Azoulay L, Krewski D. Thiazolidinedione drugs in the treatment of type 2 diabetes mellitus: past, present and future. Crit Rev Toxicol 2017; 48:52-108. [PMID: 28816105 DOI: 10.1080/10408444.2017.1351420] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Thiazolidinedione (TZD) drugs used in the treatment of type 2 diabetes mellitus (T2DM) have proven effective in improving insulin sensitivity, hyperglycemia, and lipid metabolism. Though well tolerated by some patients, their mechanism of action as ligands of peroxisome proliferator-activated receptors (PPARs) results in the activation of several pathways in addition to those responsible for glycemic control and lipid homeostasis. These pathways, which include those related to inflammation, bone formation, and cell proliferation, may lead to adverse health outcomes. As treatment with TZDs has been associated with adverse hepatic, cardiovascular, osteological, and carcinogenic events in some studies, the role of TZDs in the treatment of T2DM continues to be debated. At the same time, new therapeutic roles for TZDs are being investigated, with new forms and isoforms currently in the pre-clinical phase for use in the prevention and treatment of some cancers, inflammatory diseases, and other conditions. The aims of this review are to provide an overview of the mechanism(s) of action of TZDs, a review of their safety for use in the treatment of T2DM, and a perspective on their current and future therapeutic roles.
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Affiliation(s)
- Melissa A Davidson
- a Faculty of Health Sciences , University of Ottawa , Ottawa , Canada.,b McLaughlin Centre for Population Health Risk Assessment , Ottawa , Canada
| | - Donald R Mattison
- b McLaughlin Centre for Population Health Risk Assessment , Ottawa , Canada.,c Risk Sciences International , Ottawa , Canada
| | - Laurent Azoulay
- d Center for Clinical Epidemiology , Lady Davis Research Institute, Jewish General Hospital , Montreal , Canada.,e Department of Oncology , McGill University , Montreal , Canada
| | - Daniel Krewski
- a Faculty of Health Sciences , University of Ottawa , Ottawa , Canada.,b McLaughlin Centre for Population Health Risk Assessment , Ottawa , Canada.,c Risk Sciences International , Ottawa , Canada.,f Faculty of Medicine , University of Ottawa , Ottawa , Canada
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37
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Dijk W, Mattijssen F, de la Rosa Rodriguez M, Loza Valdes A, Loft A, Mandrup S, Kalkhoven E, Qi L, Borst JW, Kersten S. Hypoxia-Inducible Lipid Droplet-Associated Is Not a Direct Physiological Regulator of Lipolysis in Adipose Tissue. Endocrinology 2017; 158:1231-1251. [PMID: 28323980 PMCID: PMC5460841 DOI: 10.1210/en.2016-1809] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 03/13/2017] [Indexed: 12/20/2022]
Abstract
Triglycerides are stored in specialized organelles called lipid droplets. Numerous proteins have been shown to be physically associated with lipid droplets and govern their function. Previously, the protein hypoxia-inducible lipid droplet-associated (HILPDA) was localized to lipid droplets and was suggested to inhibit triglyceride lipolysis in hepatocytes. We confirm the partial localization of HILPDA to lipid droplets and show that HILPDA is highly abundant in adipose tissue, where its expression is controlled by the peroxisome proliferator-activated receptor γ and by β-adrenergic stimulation. Levels of HILPDA markedly increased during 3T3-L1 adipocyte differentiation. Nevertheless, silencing of Hilpda using small interfering RNA or overexpression of Hilpda using adenovirus did not show a clear impact on 3T3-L1 adipogenesis. Following β-adrenergic stimulation, the silencing of Hilpda in adipocytes did not significantly alter the release of nonesterified fatty acids (NEFA) and glycerol. By contrast, adenoviral-mediated overexpression of Hilpda modestly attenuated the release of NEFA from adipocytes following β-adrenergic stimulation. In mice, adipocyte-specific inactivation of Hilpda had no effect on plasma levels of NEFA and glycerol after fasting, cold exposure, or pharmacological β-adrenergic stimulation. In addition, other relevant metabolic parameters were unchanged by adipocyte-specific inactivation of Hilpda. Taken together, we find that HILPDA is highly abundant in adipose tissue, where its levels are induced by peroxisome proliferator-activated receptor γ and β-adrenergic stimulation. In contrast to the reported inhibition of lipolysis by HILPDA in hepatocytes, our data do not support an important direct role of HILPDA in the regulation of lipolysis in adipocytes in vivo and in vitro.
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Affiliation(s)
- Wieneke Dijk
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition, Wageningen University, 6708 WE Wageningen, The Netherlands
| | - Frits Mattijssen
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition, Wageningen University, 6708 WE Wageningen, The Netherlands
| | - Montserrat de la Rosa Rodriguez
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition, Wageningen University, 6708 WE Wageningen, The Netherlands
| | - Angel Loza Valdes
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition, Wageningen University, 6708 WE Wageningen, The Netherlands
| | - Anne Loft
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
| | - Susanne Mandrup
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
| | - Eric Kalkhoven
- Molecular Cancer Research and Center for Molecular Medicine, University Medical Centre Utrecht, 3584 CG Utrecht, The Netherlands
| | - Ling Qi
- University of Michigan Medical School, Ann Arbor, Michigan 48105
| | - Jan Willem Borst
- Laboratory of Biochemistry, Microspectroscopy Centre, Wageningen University, 6708 WE Wageningen, The Netherlands
| | - Sander Kersten
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition, Wageningen University, 6708 WE Wageningen, The Netherlands
- University of Michigan Medical School, Ann Arbor, Michigan 48105
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38
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Offermanns S. Hydroxy-Carboxylic Acid Receptor Actions in Metabolism. Trends Endocrinol Metab 2017; 28:227-236. [PMID: 28087125 DOI: 10.1016/j.tem.2016.11.007] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Revised: 11/09/2016] [Accepted: 11/09/2016] [Indexed: 12/09/2022]
Abstract
Lactic acid, the ketone body 3-hydroxy-butyric acid, also known as β-hydroxybutyrate, and the β-oxidation intermediate 3-hydroxy-octanoic acid are hydroxy-carboxylic acids (HCAs) that serve as intermediates of energy metabolism. However, they also regulate cellular functions, in part by directly activating the G protein-coupled receptors HCA1/GPR81, HCA2/GPR109A, and HCA3/GPR109B. During the past decade, it has become clear that HCA receptors help to maintain homeostasis under changing metabolic and dietary conditions, by controlling metabolic, immune, and other body functions. Work based on genetic mouse models and synthetic ligands of HCA receptors has, in addition, shown that members of this receptor family can serve as targets for the prevention and therapy of diseases such as metabolic and inflammatory disorders.
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Affiliation(s)
- Stefan Offermanns
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Ludwigstrasse 43, 61231 Bad Nauheim, Germany; Medical Faculty, University of Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
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39
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Insulinotropic effects of GPR120 agonists are altered in obese diabetic and obese non-diabetic states. Clin Sci (Lond) 2016; 131:247-260. [PMID: 27980130 DOI: 10.1042/cs20160545] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 12/13/2016] [Accepted: 12/15/2016] [Indexed: 02/06/2023]
Abstract
G-protein-coupled receptor 120 (GPR120) is a putative target for obesity and diabetes therapies. However, it remains controversial whether resident GPR120 plays a direct regulatory role in islet β-cell insulin secretion. The present study examined this issue in isolated rodent islets and rat β-cell line INS-1E, and assessed the role of GPR120 in islet insulin secretion in obese non-diabetic (OND) and diabetic states. GPR120 expression was detected in rodent islet β-cells. Docosahexaenoic acid (DHA) and synthetic GPR120 agonist GSK137647 (GSK) augmented insulin release from rat/mouse islets and INS-1E; DHA effects were partially mediated by GPR40. GPR120 knockdown and overexpression attenuated and enhanced DHA effects in INS-1E respectively. DHA and GSK improved postprandial hyperglycaemia of diabetic mice. Inhibition of calcium signalling in INS-1E reduced GPR120 activation-induced insulinotropic effects. The insulinotropic effects of DHA/GSK were amplified in OND rat islets, but diminished in diabetic rat islets. GPR120 and peroxisome proliferator-activated receptor γ (PPARγ) expression were elevated in OND islets and palmitic acid (PA)-treated INS-1E, but reduced in diabetic islets and high glucose-treated INS-1E. PPARγ activation increased GPR120 expression in rat islets and INS-1E. DHA and GSK induced protein kinase B (Akt)/extracellular signal-regulated kinase (ERK) phosphorylation in rodent islets and INS-1E, and these effects were altered in OND and diabetic states. Taken together, the present study indicates that (i) GPR120 activation has an insulinotropic influence on β-cells with the involvement of calcium signalling; (ii) GPR120 expression in β-cells and GPR120-mediated insulinotropic effects are altered in OND and diabetic states in distinct ways, and these alterations may be mediated by PPARγ.
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40
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Quercetin Impacts Expression of Metabolism- and Obesity-Associated Genes in SGBS Adipocytes. Nutrients 2016; 8:nu8050282. [PMID: 27187453 PMCID: PMC4882695 DOI: 10.3390/nu8050282] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 05/04/2016] [Accepted: 05/05/2016] [Indexed: 12/12/2022] Open
Abstract
Obesity is characterized by the rapid expansion of visceral adipose tissue, resulting in a hypoxic environment in adipose tissue which leads to a profound change of gene expression in adipocytes. As a consequence, there is a dysregulation of metabolism and adipokine secretion in adipose tissue leading to the development of systemic inflammation and finally resulting in the onset of metabolic diseases. The flavonoid quercetin as well as other secondary plant metabolites also referred to as phytochemicals have anti-oxidant, anti-inflammatory, and anti-diabetic effects known to be protective in view of obesity-related-diseases. Nevertheless, its underlying molecular mechanism is still obscure and thus the focus of this study was to explore the influence of quercetin on human SGBS (Simpson Golabi Behmel Syndrome) adipocytes’ gene expression. We revealed for the first time that quercetin significantly changed expression of adipokine (Angptl4, adipsin, irisin and PAI-1) and glycolysis-involved (ENO2, PFKP and PFKFB4) genes, and that this effect not only antagonized but in part even overcompensated the effect mediated by hypoxia in adipocytes. Thus, these results are explained by the recently proposed hypothesis that the protective effect of quercetin is not solely due to its free radical-scavenging activity but also to a direct effect on mitochondrial processes, and they demonstrate that quercetin might have the potential to counteract the development of obesity-associated complications.
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Nakamichi R, Miranda EP, Lobo SMDV, Tristão VR, Dalboni MA, Quinto BMR, Batista MC. Action of nicotinic acid on the reversion of hypoxic-inflammatory link on 3T3-L1 adipocytes. Lipids Health Dis 2016; 15:91. [PMID: 27164826 PMCID: PMC4862071 DOI: 10.1186/s12944-016-0260-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 05/03/2016] [Indexed: 01/08/2023] Open
Abstract
Background Hypoxia resulting from adipocyte expansion is considered the basis of the inflammatory milieu observed in Metabolic Syndrome. Nicotinic acid can act on adipocytes interfering on the inflammatory response. In this study, we investigated the role of HIF-1 α (hypoxia-inducible factor -1 alpha) in the inflammatory process induced by hypoxia. The effect of nicotinic acid on the PPARs (peroxisome proliferator-activated receptors) expression during the inflammatory response was assessed over its action under HIF-1 α in 3T3-L1 adipocytes submitted to hypoxia. Methods 3T3-L1 adipocytes were pre-treated with nicotinic acid and incubated under hypoxic conditions. The level of adipokines and HIF-1 α were quantified using immunoassays. Adipokine expression was measured using real-time PCR, whereas PPARs and HIF-1 α expression were analyzed by western blot. The statistical significance of the differences between variables studied was determined by analysis of variance (ANOVA) complemented by Bonferroni’s test. Results The results demonstrated an increase in leptin and PAI-1 (plasminogen activator inhibitor-1) expression, while adiponectin production decreased under hypoxia. In parallel, induction with hypoxia enhanced HIF-1 α expression, despite causing reduced expression of PPAR α and PPAR γ. However, nicotinic acid reversed adipokine modulation under hypoxic conditions, leading to decreased HIF-1 α expression and increased PPARs expression. Conclusions Our findings suggest that nicotinic acid blunt the inflammatory response resulting from hypoxia by the reduction of HIF-1 α expression and concomitant increase of PPARs α and γ expression in 3T3-L1 adipocytes.
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Affiliation(s)
- Renata Nakamichi
- Nephrology Division, Department of Medicine, Universidade Federal de São Paulo, Rua Pedro de Toledo 781, Vila Clementino, São Paulo, Brazil.
| | - Erika Prates Miranda
- Nephrology Division, Department of Medicine, Universidade Federal de São Paulo, Rua Pedro de Toledo 781, Vila Clementino, São Paulo, Brazil
| | - Sylvia Madeira de Vergueiro Lobo
- Nephrology Division, Department of Medicine, Universidade Federal de São Paulo, Rua Pedro de Toledo 781, Vila Clementino, São Paulo, Brazil
| | - Vivian Regina Tristão
- Nephrology Division, Department of Medicine, Universidade Federal de São Paulo, Rua Pedro de Toledo 781, Vila Clementino, São Paulo, Brazil
| | - Maria Aparecida Dalboni
- Nephrology Division, Department of Medicine, Universidade Federal de São Paulo, Rua Pedro de Toledo 781, Vila Clementino, São Paulo, Brazil.,Universidade Nove de Julho, São Paulo, Brazil
| | - Beata Marie Redublo Quinto
- Nephrology Division, Department of Medicine, Universidade Federal de São Paulo, Rua Pedro de Toledo 781, Vila Clementino, São Paulo, Brazil
| | - Marcelo Costa Batista
- Nephrology Division, Department of Medicine, Universidade Federal de São Paulo, Rua Pedro de Toledo 781, Vila Clementino, São Paulo, Brazil.,Dialysis Unit, Intensive Care Center, Hospital Israelita Albert Einstein, São Paulo, Brazil.,Division of Nephrology, Tufts University School of Medicine, Boston, USA
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42
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Weber M, Locher L, Huber K, Kenéz Á, Rehage J, Tienken R, Meyer U, Dänicke S, Sauerwein H, Mielenz M. Longitudinal changes in adipose tissue of dairy cows from late pregnancy to lactation. Part 1: The adipokines apelin and resistin and their relationship to receptors linked with lipolysis. J Dairy Sci 2016; 99:1549-1559. [DOI: 10.3168/jds.2015-10131] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Accepted: 10/16/2015] [Indexed: 12/13/2022]
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43
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Shomali T, Kamalpour M, Fazeli M, Rafati A. Expression of HCA2 Receptors in Femoral Epiphysis and Metaphysis of Rats with Dexamethasone-Induced Osteoporosis. INTERNATIONAL JOURNAL OF MOLECULAR AND CELLULAR MEDICINE 2016; 5:106-13. [PMID: 27478807 PMCID: PMC4947215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 06/13/2016] [Indexed: 12/04/2022]
Abstract
The present study describes the changes in expression of hydroxy- carboxylic acid receptor 2 (HCA2 receptor) in femoral epiphysis and metaphysis of rats with glucocorticoid-induced osteoporosis (GIO). 16 growing male Sprauge dawley rats were randomly divided into two equal groups consisting of normal control and rats that were rendered osteoporotic by receiving 0.1 mg/kg/day dexamethasone subcutaneously. After 4 weeks, all rats were sacrificed and immediately right and left femoral bones were removed for RT-qPCR and histological examination, respectively. Immunohistochemical parameters using a primary rabbit polyclonal GPR109A antibody in hematoxylin and eosin- counter stained slides were determined. HCA2 receptor expression was evaluated using RT- qPCR. Qualitative and histomorphometric evaluation of slides revealed the establishment of glucocorticoid- induced osteoporosis (GIO) in rats treated with dexamethasone. In immunohistochemical study, dexamethasone administration appreciably reduced receptor density in all evaluated cell types and in total slides as compared to control. mRNA level of HCA2 receptor gene was reduced in dexamethasone- treated group. GIO may be associated with down regulation of HCA2 receptors in proximal femoral bone of rats at mRNA as well as protein level in no- cell type-specific manner, although reduction in protein expression needs to be further confirmed by western blotting.
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Affiliation(s)
- Tahoora Shomali
- Corresponding author: Tahoora Shomali, Division of Pharmacology and Toxicology, Department of Basic Sciences, School of Veterinary Medicine, Shiraz University, Shiraz, Iran. E-mail:
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Salmina AB, Kuvacheva NV, Morgun AV, Komleva YK, Pozhilenkova EA, Lopatina OL, Gorina YV, Taranushenko TE, Petrova LL. Glycolysis-mediated control of blood-brain barrier development and function. Int J Biochem Cell Biol 2015; 64:174-84. [PMID: 25900038 DOI: 10.1016/j.biocel.2015.04.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 03/24/2015] [Accepted: 04/10/2015] [Indexed: 12/29/2022]
Abstract
The blood-brain barrier (BBB) consists of differentiated cells integrating in one ensemble to control transport processes between the central nervous system (CNS) and peripheral blood. Molecular organization of BBB affects the extracellular content and cell metabolism in the CNS. Developmental aspects of BBB attract much attention in recent years, and barriergenesis is currently recognized as a very important and complex mechanism of CNS development and maturation. Metabolic control of angiogenesis/barriergenesis may be provided by glucose utilization within the neurovascular unit (NVU). The role of glycolysis in the brain has been reconsidered recently, and it is recognized now not only as a process active in hypoxic conditions, but also as a mechanism affecting signal transduction, synaptic activity, and brain development. There is growing evidence that glycolysis-derived metabolites, particularly, lactate, affect barriergenesis and functioning of BBB. In the brain, lactate produced in astrocytes or endothelial cells can be transported to the extracellular space via monocarboxylate transporters (MCTs), and may act on the adjoining cells via specific lactate receptors. Astrocytes are one of the major sources of lactate production in the brain and significantly contribute to the regulation of BBB development and functioning. Active glycolysis in astrocytes is required for effective support of neuronal activity and angiogenesis, while endothelial cells regulate bioavailability of lactate for brain cells adjusting its bidirectional transport through the BBB. In this article, we review the current knowledge with regard to energy production in endothelial and astroglial cells within the NVU. In addition, we describe lactate-driven mechanisms and action of alternative products of glucose metabolism affecting BBB structural and functional integrity in developing and mature brain.
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Affiliation(s)
- Alla B Salmina
- Dept of Biochemistry, Medical, Pharmaceutical & Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia; Research Institute of Molecular Medicine & Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia.
| | - Natalia V Kuvacheva
- Dept of Biochemistry, Medical, Pharmaceutical & Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia; Research Institute of Molecular Medicine & Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia.
| | - Andrey V Morgun
- Research Institute of Molecular Medicine & Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia.
| | - Yulia K Komleva
- Dept of Biochemistry, Medical, Pharmaceutical & Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia; Research Institute of Molecular Medicine & Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia.
| | - Elena A Pozhilenkova
- Dept of Biochemistry, Medical, Pharmaceutical & Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia; Research Institute of Molecular Medicine & Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia.
| | - Olga L Lopatina
- Dept of Biochemistry, Medical, Pharmaceutical & Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia; Research Institute of Molecular Medicine & Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia.
| | - Yana V Gorina
- Dept of Biochemistry, Medical, Pharmaceutical & Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia; Research Institute of Molecular Medicine & Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia.
| | - Tatyana E Taranushenko
- Research Institute of Molecular Medicine & Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia.
| | - Lyudmila L Petrova
- Dept of Biochemistry, Medical, Pharmaceutical & Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia; Research Institute of Molecular Medicine & Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, P. Zheleznyaka Str. 1, Krasnoyarsk, 660022, Russia.
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Amisten S, Neville M, Hawkes R, Persaud SJ, Karpe F, Salehi A. An atlas of G-protein coupled receptor expression and function in human subcutaneous adipose tissue. Pharmacol Ther 2015; 146:61-93. [PMID: 25242198 DOI: 10.1016/j.pharmthera.2014.09.007] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 09/09/2014] [Indexed: 12/17/2022]
Abstract
G-protein coupled receptors (GPCRs) are involved in the regulation of adipose tissue function, but the total number of GPCRs expressed by human subcutaneous adipose tissue, as well as their function and interactions with drugs, is poorly understood. We have constructed an atlas of all GPCRs expressed by human subcutaneous adipose tissue: the 'adipose tissue GPCRome', to support the exploration of novel control nodes in metabolic and endocrine functions. This atlas describes how adipose tissue GPCRs regulate lipolysis, insulin resistance and adiponectin and leptin secretion. We also discuss how adipose tissue GPCRs interact with their endogenous ligands and with GPCR-targeting drugs, with a focus on how drug/receptor interactions may affect lipolysis, and present a model predicting how GPCRs with unknown effects on lipolysis might modulate cAMP-regulated lipolysis. Subcutaneous adipose tissue expresses 163 GPCRs, a majority of which have unknown effects on lipolysis, insulin resistance and adiponectin and leptin secretion. These GPCRs are activated by 180 different endogenous ligands, and are the targets of a large number of clinically used drugs. We identified 119 drugs, acting on 23 GPCRs, that are predicted to stimulate lipolysis and 173 drugs, acting on 25 GPCRs, that are predicted to inhibit lipolysis. This atlas highlights knowledge gaps in the current understanding of adipose tissue GPCR function, and identifies GPCR/ligand/drug interactions that might affect lipolysis, which is important for understanding and predicting metabolic side effects of drugs. This approach may aid in the design of new, safer therapeutic agents, with fewer undesired effects on lipid homeostasis.
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Affiliation(s)
- Stefan Amisten
- Diabetes Research Group, Division of Diabetes & Nutritional Sciences, King's College London, Faculty of Life Sciences & Medicine, London, UK; Oxford Centre for Diabetes, Endocrinology & Metabolism, University of Oxford, Oxford, UK.
| | - Matt Neville
- Oxford Centre for Diabetes, Endocrinology & Metabolism, University of Oxford, Oxford, UK; NIHR Oxford Biomedical Research Centre, Churchill Hospital, Oxford OX3 7LE, UK
| | - Ross Hawkes
- Diabetes Research Group, Division of Diabetes & Nutritional Sciences, King's College London, Faculty of Life Sciences & Medicine, London, UK
| | - Shanta J Persaud
- Diabetes Research Group, Division of Diabetes & Nutritional Sciences, King's College London, Faculty of Life Sciences & Medicine, London, UK
| | - Fredrik Karpe
- Oxford Centre for Diabetes, Endocrinology & Metabolism, University of Oxford, Oxford, UK; NIHR Oxford Biomedical Research Centre, Churchill Hospital, Oxford OX3 7LE, UK.
| | - Albert Salehi
- Department of Clinical Science, UMAS, Clinical Research Center, University of Lund, Sweden
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Nicotinic acid increases adiponectin secretion from differentiated bovine preadipocytes through G-protein coupled receptor signaling. Int J Mol Sci 2014; 15:21401-18. [PMID: 25411802 PMCID: PMC4264232 DOI: 10.3390/ijms151121401] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 10/20/2014] [Accepted: 11/06/2014] [Indexed: 12/17/2022] Open
Abstract
The transition period in dairy cows (3 weeks prepartum until 3 weeks postpartum) is associated with substantial mobilization of energy stores, which is often associated with metabolic diseases. Nicotinic acid (NA) is an antilipolytic and lipid-lowering compound used to treat dyslipidaemia in humans, and it also reduces non-esterified fatty acids in cattle. In mice the G-protein coupled receptor 109A (GPR109A) ligand NA positively affects the secretion of adiponectin, an important modulator of glucose and fat metabolism. In cattle, the corresponding data linking NA to adiponectin are missing. Our objective was to examine the effects of NA on adiponectin and AMPK protein abundance and the expression of mRNAs of related genes such as chemerin, an adipokine that enhances adiponectin secretion in vitro. Differentiated bovine adipocytes were incubated with pertussis toxin (PTX) to verify the involvement of GPR signaling, and treated with 10 or 15 µM NA for 12 or 24 h. NA increased adiponectin concentrations (p ≤ 0.001) and the mRNA abundances of GPR109A (p ≤ 0.05) and chemerin (p ≤ 0.01). Pre-incubation with PTX reduced the adiponectin response to NA (p ≤ 0.001). The NA-stimulated secretion of adiponectin and the mRNA expression of chemerin in the bovine adipocytes were suggestive of GPR signaling-dependent improved insulin sensitivity and/or adipocyte metabolism in dairy cows.
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Bremer K, Kocha K, Snider T, Moyes C. Energy metabolism and cytochrome oxidase activity: linking metabolism to gene expression. CAN J ZOOL 2014. [DOI: 10.1139/cjz-2013-0267] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Modification of mitochondrial content demands the synthesis of hundreds of proteins encoded by nuclear and mitochondrial genomes. The responsibility for coordination of this process falls to nuclear-encoded master regulators of transcription. DNA-binding proteins and coactivators integrate information from energy-sensing pathways and hormones to alter mitochondrial gene expression. In mammals, the signaling cascade for mitochondrial biogenesis can be described as follows: hormonal signals and energetic information are sensed by protein-modifying enzymes that in turn regulate the post-translational modification of transcription factors. Once activated, transcription-factor complexes form on promoter elements of many of the nuclear-encoded mitochondrial genes, recruiting proteins that remodel chromatin and initiate transcription. One master regulator in mammals, PGC-1α, is well studied because of its role in determining the metabolic phenotype of muscles, but also due to its importance in mitochondria-related metabolic diseases. However, relatively little is known about the role of this pathway in other vertebrates. These uncertainties raise broader questions about the evolutionary origins of the pathway and its role in generating the diversity in muscle metabolic phenotypes seen in nature.
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Affiliation(s)
- K. Bremer
- Department of Biology, Biosciences Complex, Queen’s University, Kingston, ON K7L 3N6, Canada
| | - K.M. Kocha
- Department of Biology, Biosciences Complex, Queen’s University, Kingston, ON K7L 3N6, Canada
| | - T. Snider
- Department of Biology, Biosciences Complex, Queen’s University, Kingston, ON K7L 3N6, Canada
| | - C.D. Moyes
- Department of Biology, Biosciences Complex, Queen’s University, Kingston, ON K7L 3N6, Canada
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Friedrichs P, Saremi B, Winand S, Rehage J, Dänicke S, Sauerwein H, Mielenz M. Energy and metabolic sensing G protein-coupled receptors during lactation-induced changes in energy balance. Domest Anim Endocrinol 2014; 48:33-41. [PMID: 24906926 DOI: 10.1016/j.domaniend.2014.01.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 01/11/2014] [Accepted: 01/29/2014] [Indexed: 11/23/2022]
Abstract
The free fatty acid receptor FFA1, FFA2, and FFA3 and hydroxy-carboxylic acid receptor (HCA2) are G protein-coupled receptors, acting as energy and metabolic sensors. Herein, we characterized the tissue-specific mRNA abundance of genes encoding for these receptors at different stages of lactation. In addition, potential effects of supplementation with or without conjugated linoleic acids (CLA) were tested. Tissues from pluriparous cows (subcutaneous adipose tissue [SAT] and liver) and from primiparous cows (3 SAT locations, 3 visceral adipose tissues, liver, mammary gland, and skeletal muscle) were used from 2 separate trials. In primiparous cows, the mRNA abundance of all receptors (FFA3 was not detectable by the applied protocol in muscle and udder) was lowest in muscle (P < 0.05). With the exception of FFA1, gene expression of the investigated receptors was higher in adipose tissue than in the non-adipose tissue. Expression of FFA1 in liver (P < 0.03), FFAR2 in SAT (P < 0.01), and HCA2 in SAT (P < 0.01) from pluriparous cows changed during the observation period (days 21 to 252 relative to parturition). The correlation between mRNA abundance of HCA2 and peroxisome proliferator-activated receptor gamma (PPARG) and likewise PPARG2 (P < 0.01) in SAT indicates a link between HCA2 and PPARG. Differences in receptor mRNA abundance between the CLA-fed and the control animals were scarce and limited to HCA2 and FFA1 in 1 and 2 time points, respectively (less hepatic HCA2mRNA in CLA-fed pluriparous cows and greater FFA1 mRNA abundance in 2 visceral adipose tissue depots in CLA-treated primiparous cows). In view of the metabolic changes occurring during the different phases of lactation, in particular, the altered concentrations of non-esterified fatty acids and β-hydroxybutyrate acting as receptor ligands, the longitudinal tissue-specific characterization provided herein allows for a first insight into the regulation of these receptors at the gene expression level.
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Affiliation(s)
- P Friedrichs
- Institute of Animal Science, Physiology and Hygiene Unit, University of Bonn, Katzenburgweg 7 - 9, 53115 Bonn, Germany
| | - B Saremi
- Institute of Animal Science, Physiology and Hygiene Unit, University of Bonn, Katzenburgweg 7 - 9, 53115 Bonn, Germany
| | - S Winand
- Institute of Animal Science, Physiology and Hygiene Unit, University of Bonn, Katzenburgweg 7 - 9, 53115 Bonn, Germany
| | - J Rehage
- Clinic for Cattle, School of Veterinary Medicine Hannover, 30173 Hannover, Germany
| | - S Dänicke
- Institute of Animal Nutrition, Friedrich-Loeffler-Institute (FLI), Federal Research Institute for Animal Health, 38116 Braunschweig, Germany
| | - H Sauerwein
- Institute of Animal Science, Physiology and Hygiene Unit, University of Bonn, Katzenburgweg 7 - 9, 53115 Bonn, Germany
| | - M Mielenz
- Institute of Animal Science, Physiology and Hygiene Unit, University of Bonn, Katzenburgweg 7 - 9, 53115 Bonn, Germany.
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Early adipogenesis is regulated through USP7-mediated deubiquitination of the histone acetyltransferase TIP60. Nat Commun 2014; 4:2656. [PMID: 24141283 DOI: 10.1038/ncomms3656] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 09/23/2013] [Indexed: 01/27/2023] Open
Abstract
Transcriptional coregulators, including the acetyltransferase Tip60, have a key role in complex cellular processes such as differentiation. Whereas post-translational modifications have emerged as an important mechanism to regulate transcriptional coregulator activity, the identification of the corresponding demodifying enzymes has remained elusive. Here we show that the expression of the Tip60 protein, which is essential for adipocyte differentiation, is regulated through polyubiquitination on multiple residues. USP7, a dominant deubiquitinating enzyme in 3T3-L1 adipocytes and mouse adipose tissue, deubiquitinates Tip60 both in intact cells and in vitro and increases Tip60 protein levels. Furthermore, inhibition of USP7 expression and activity decreases adipogenesis. Transcriptome analysis reveals several cell cycle genes to be co-regulated by both Tip60 and USP7. Knockdown of either factor results in impaired mitotic clonal expansion, an early step in adipogenesis. These results reveal deubiquitination of a transcriptional coregulator to be a key mechanism in the regulation of early adipogenesis.
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Trans-cinnamic acid increases adiponectin and the phosphorylation of AMP-activated protein kinase through G-protein-coupled receptor signaling in 3T3-L1 adipocytes. Int J Mol Sci 2014; 15:2906-15. [PMID: 24557583 PMCID: PMC3958889 DOI: 10.3390/ijms15022906] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 01/24/2014] [Accepted: 02/10/2014] [Indexed: 12/12/2022] Open
Abstract
Adiponectin and intracellular 5′adenosine monophosphate-activated protein kinase (AMPK) are important modulators of glucose and fat metabolism. Cinnamon exerts beneficial effects by improving insulin sensitivity and blood lipids, e.g., through increasing adiponectin concentrations and AMPK activation. The underlying mechanism is unknown. The Gi/Go-protein-coupled receptor (GPR) 109A stimulates adiponectin secretion after binding its ligand niacin. Trans-cinnamic acid (tCA), a compound of cinnamon is another ligand. We hypothesize whether AMPK activation and adiponectin secretion by tCA is transmitted by GPR signaling. Differentiated 3T3-L1 cells were incubated with pertussis toxin (PTX), an inhibitor of Gi/Go-protein-coupling, and treated with different tCA concentrations. Treatment with tCA increased adiponectin and the pAMPK/AMPK ratio (p ≤ 0.001). PTX incubation abolished the increased pAMPK/AMPK ratio and adiponectin secretion. The latter remained increased compared to controls (p ≤ 0.002). tCA treatment stimulated adiponectin secretion and AMPK activation; the inhibitory effect of PTX suggests GPR is involved in tCA stimulated signaling.
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