1
|
Cornejo MP, Mustafá ER, Cassano D, Banères JL, Raingo J, Perello M. The ups and downs of growth hormone secretagogue receptor signaling. FEBS J 2021; 288:7213-7229. [PMID: 33460513 DOI: 10.1111/febs.15718] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 01/05/2021] [Accepted: 01/14/2021] [Indexed: 12/14/2022]
Abstract
The growth hormone secretagogue receptor (GHSR) has emerged as one of the most fascinating molecules from the perspective of neuroendocrine control. GHSR is mainly expressed in the pituitary and the brain, and plays key roles regulating not only growth hormone secretion but also food intake, adiposity, body weight, glucose homeostasis and other complex functions. Quite atypically, GHSR signaling displays a basal constitutive activity that can be up- or downregulated by two digestive system-derived hormones: the octanoylated-peptide ghrelin and the liver-expressed antimicrobial peptide 2 (LEAP2), which was recently recognized as an endogenous GHSR ligand. The existence of two ligands with contrary actions indicates that GHSR activity can be tightly regulated and that the receptor displays the capability to integrate such opposing inputs in order to provide a balanced intracellular signal. This article provides a summary of the current understanding of the biology of ghrelin, LEAP2 and GHSR and discusses the reconceptualization of the cellular and physiological implications of the ligand-regulated GHSR signaling, based on the latest findings.
Collapse
Affiliation(s)
- María P Cornejo
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET), Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], Buenos Aires, Argentina
| | - Emilio R Mustafá
- Laboratory of Electrophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET), Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], Buenos Aires, Argentina
| | - Daniela Cassano
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET), Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], Buenos Aires, Argentina
| | - Jean-Louis Banères
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier, Faculté de Pharmacie, Montpellier cedex 5, France
| | - Jesica Raingo
- Laboratory of Electrophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET), Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], Buenos Aires, Argentina
| | - Mario Perello
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET), Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], Buenos Aires, Argentina
| |
Collapse
|
2
|
Lu X, Huang L, Huang Z, Feng D, Clark RJ, Chen C. LEAP-2: An Emerging Endogenous Ghrelin Receptor Antagonist in the Pathophysiology of Obesity. Front Endocrinol (Lausanne) 2021; 12:717544. [PMID: 34512549 PMCID: PMC8428150 DOI: 10.3389/fendo.2021.717544] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 07/28/2021] [Indexed: 11/20/2022] Open
Abstract
Liver-expressed antimicrobial peptide 2 (LEAP-2), originally described as an antimicrobial peptide, has recently been recognized as an endogenous blocker of growth hormone secretagogue receptor 1a (GHS-R1a). GHS-R1a, also known as ghrelin receptor, is a G protein-coupled receptor (GPCR) widely distributed on the hypothalamus and pituitary gland where it exerts its major functions of regulating appetite and growth hormone (GH) secretion. The activity of GHS-R1a is controlled by two counter-regulatory endogenous ligands: Ghrelin (activation) and LEAP-2 (inhibition). Ghrelin activates GHS-R1a on the neuropeptide Y/Agouti-related protein (NPY/AgRP) neurons at the arcuate nucleus (ARC) to promote appetite, and on the pituitary somatotrophs to stimulate GH release. On the flip side, LEAP-2, acts both as an endogenous competitive antagonist of ghrelin and an inverse agonist of constitutive GHS-R1a activity. Such a biological property of LEAP-2 vigorously blocks ghrelin's effects on food intake and hormonal secretion. In circulation, LEAP-2 displays an inverse pattern as to ghrelin; it increases with food intake and obesity (positive energy balance), whereas decreases upon fasting and weight loss (negative energy balance). Thus, the LEAP-2/ghrelin molar ratio fluctuates in response to energy status and modulation of this ratio conversely influences energy intake. Inhibiting ghrelin's activity has shown beneficial effects on obesity in preclinical experiments, which sheds light on LEAP-2's anti-obesity potential. In this review, we will analyze LEAP-2's effects from a metabolic point of view with a focus on metabolic hormones (e.g., ghrelin, GH, and insulin), and discuss LEAP-2's potential as a promising therapeutic target for obesity.
Collapse
Affiliation(s)
- Xuehan Lu
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Lili Huang
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Zhengxiang Huang
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Dandan Feng
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
- Department of Physiology, Xiangya Medical School, Central South University, Changsha, China
| | - Richard J. Clark
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Chen Chen
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
- *Correspondence: Chen Chen,
| |
Collapse
|
3
|
Shi Y, Lam SM, Liu H, Luo G, Zhang J, Yao S, Li J, Zheng L, Xu N, Zhang X, Shui G. Comprehensive lipidomics in apoM -/- mice reveals an overall state of metabolic distress and attenuated hepatic lipid secretion into the circulation. J Genet Genomics 2020; 47:523-534. [PMID: 33309167 DOI: 10.1016/j.jgg.2020.08.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 08/03/2020] [Accepted: 08/05/2020] [Indexed: 12/14/2022]
Abstract
Apolipoprotein M (apoM) participates in both high-density lipoprotein and cholesterol metabolism. Little is known about how apoM affects lipid composition of the liver and serum. In this study, we systemically investigated the effects of apoM on liver and plasma lipidomes and how apoM participates in lipid cycling, via apoM knockout in mice and the human SMMC-7721 cell line. We used integrated mass spectrometry-based lipidomics approaches to semiquantify more than 600 lipid species from various lipid classes, which include free fatty acids, glycerolipids, phospholipids, sphingolipids, glycosphingolipids, cholesterol, and cholesteryl esters (CEs), in apoM-/- mouse. Hepatic accumulation of neutral lipids, including CEs, triacylglycerols, and diacylglycerols, was observed in apoM-/- mice; while serum lipidomic analyses showed that, in contrast to the liver, the overall levels of CEs and saturated/monounsaturated fatty acids were markedly diminished. Furthermore, the level of ApoB-100 was dramatically increased in the liver, whereas significant reductions in both ApoB-100 and low-density lipoprotein (LDL) cholesterol were observed in the serum of apoM-/- mice, which indicated attenuated hepatic LDL secretion into the circulation. Lipid profiles and proinflammatory cytokine levels indicated that apoM-/- leads to hepatic steatosis and an overall state of metabolic distress. Taken together, these results revealed that apoM knockout leads to hepatic steatosis, impaired lipid secretion, and an overall state of metabolic distress.
Collapse
Affiliation(s)
- Yuanping Shi
- Department of Comprehensive Laboratory, The Third Affiliated Hospital of Soochow University, Changzhou, 213003, China
| | - Sin Man Lam
- Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Hong Liu
- Department of Cardiothoracic Surgery, The Third Affiliated Hospital of Soochow University, Changzhou, 213003, China
| | - Guanghua Luo
- Department of Comprehensive Laboratory, The Third Affiliated Hospital of Soochow University, Changzhou, 213003, China
| | - Jun Zhang
- Department of Comprehensive Laboratory, The Third Affiliated Hospital of Soochow University, Changzhou, 213003, China
| | - Shuang Yao
- Department of Comprehensive Laboratory, The Third Affiliated Hospital of Soochow University, Changzhou, 213003, China
| | - Jie Li
- Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Lu Zheng
- Department of Comprehensive Laboratory, The Third Affiliated Hospital of Soochow University, Changzhou, 213003, China
| | - Ning Xu
- Section of Clinical Chemistry and Pharmacology, Institute of Laboratory Medicine, Lunds University, Klinikgatan 19, S-22185, Lund, Sweden
| | - Xiaoying Zhang
- Department of Cardiothoracic Surgery, The Third Affiliated Hospital of Soochow University, Changzhou, 213003, China.
| | - Guanghou Shui
- Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
| |
Collapse
|
4
|
Grimaldi M, Palisi A, Marino C, Montoro P, Capasso A, Novi S, Tecce MF, D’Ursi AM. NMR-based metabolomic profile of hypercholesterolemic human sera: Relationship with in vitro gene expression? PLoS One 2020; 15:e0231506. [PMID: 32298312 PMCID: PMC7162471 DOI: 10.1371/journal.pone.0231506] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 03/24/2020] [Indexed: 12/13/2022] Open
Abstract
Hypercholesterolaemia is considered an important cause of atherosclerotic cardiovascular disease. In a previous investigation, we demonstrated that cultured hepatoma cells treated with hypercholesterolaemic sera compared with cells treated with normocholesterolaemic sera show overexpression of mRNAs related to mitochondrial 3-hydroxy-3-methylglutaryl-coenzyme A synthase (HMGCS2). In the present work, using an NMR metabolomic analysis, we demonstrate that the hypercholesterolaemic blood sera previously used to treat cultured hepatoma cells are characterized by a metabolomic profile that is significantly different from the normocholesterolaemic sera. Acetate, acetone, 2-hydroxybutyrate, cysteine, valine, and glutamine are the metabolites distinguishing the two groups. Abnormalities in the concentrations of these metabolites reflect alterations in energy-related pathways, such as pantothenate and CoA biosynthesis, pyruvate, glycolysis/gluconeogenesis, the citrate cycle, and ketone bodies. Regarding ketone bodies, the pathway is regulated by HMGCS2; therefore, serum samples previously found to be able to increase HMGCS2 mRNA levels in cultured cells also contain higher amounts of the metabolites of its encoded enzyme protein product.
Collapse
Affiliation(s)
| | - Angelica Palisi
- Department of Pharmacy, University of Salerno, Fisciano, Italy
| | - Carmen Marino
- Department of Pharmacy, University of Salerno, Fisciano, Italy
| | - Paola Montoro
- Department of Pharmacy, University of Salerno, Fisciano, Italy
| | - Anna Capasso
- Department of Pharmacy, University of Salerno, Fisciano, Italy
| | - Sara Novi
- Department of Pharmacy, University of Salerno, Fisciano, Italy
| | | | - Anna Maria D’Ursi
- Department of Pharmacy, University of Salerno, Fisciano, Italy
- * E-mail:
| |
Collapse
|
5
|
Rescigno T, Tecce MF, Capasso A. Protective and Restorative Effects of Nutrients and Phytochemicals. Open Biochem J 2018; 12:46-64. [PMID: 29760813 PMCID: PMC5906970 DOI: 10.2174/1874091x01812010046] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 04/02/2018] [Accepted: 04/03/2018] [Indexed: 12/11/2022] Open
Abstract
Intoroduction: Dietary intake fundamentally provides reintegration of energy and essential nutrients to human organisms. However, its qualitative and quantitative composition strongly affects individual’s health, possibly being either a preventive or a risk factor. It was shown that nutritional status resulting from long-term exposition to specific diet formulations can outstandingly reduce incidences of most common and most important diseases of the developed world, such as cardiovascular and neoplastic diseases. Diet formulations result from different food combinations which bring specific nutrient molecules. Numerous molecules, mostly but not exclusively from vegetal foods, have been characterized among nutritional components as being particularly responsible for diet capabilities to exert risk reduction. These “bioactive nutrients” are able to produce effects which go beyond basic reintegration tasks, i.e. energetic and/or structural, but are specifically pharmacologically active within pathophysiological pathways related to many diseases, being able to selectively affect processes such as cell proliferation, apoptosis, inflammation, differentiation, angiogenesis, DNA repair and carcinogens activation. Conclusion: The present review was aimed to know the molecular mechanisms and pathways of activity of bioactive molecules; which will firstly allow search for optimal food composition and intake, and then use them as possible therapeutical targets and/or diagnostics. Also, the present review discussed the therapeutic effect of both nutrients and phytochemicals.
Collapse
Affiliation(s)
- Tania Rescigno
- Department of Pharmacy, University of Salerno, Fisciano (SA), Italy
| | - Mario F Tecce
- Department of Pharmacy, University of Salerno, Fisciano (SA), Italy
| | - Anna Capasso
- Department of Pharmacy, University of Salerno, Fisciano (SA), Italy
| |
Collapse
|
6
|
Rescigno T, Capasso A, Tecce MF. Involvement of nutrients and nutritional mediators in mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase gene expression. J Cell Physiol 2017; 233:3306-3314. [DOI: 10.1002/jcp.26177] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 08/24/2017] [Indexed: 12/16/2022]
Affiliation(s)
- Tania Rescigno
- Department of Pharmacy; University of Salerno; Fisciano Salerno Italy
| | - Anna Capasso
- Department of Pharmacy; University of Salerno; Fisciano Salerno Italy
| | | |
Collapse
|
7
|
Reyes-Reveles J, Dhingra A, Alexander D, Bragin A, Philp NJ, Boesze-Battaglia K. Phagocytosis-dependent ketogenesis in retinal pigment epithelium. J Biol Chem 2017; 292:8038-8047. [PMID: 28302729 DOI: 10.1074/jbc.m116.770784] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 03/13/2017] [Indexed: 11/06/2022] Open
Abstract
Daily, the retinal pigment epithelium (RPE) ingests a bolus of lipid and protein in the form of phagocytized photoreceptor outer segments (OS). The RPE, like the liver, expresses enzymes required for fatty acid oxidation and ketogenesis. This suggests that these pathways play a role in the disposal of lipids from ingested OS, as well as providing a mechanism for recycling metabolic intermediates back to the outer retina. In this study, we examined whether OS phagocytosis was linked to ketogenesis. We found increased levels of β-hydroxybutyrate (β-HB) in the apical medium following ingestion of OS by human fetal RPE and ARPE19 cells cultured on Transwell inserts. No increase in ketogenesis was observed following ingestion of oxidized OS or latex beads. Our studies further defined the connection between OS phagocytosis and ketogenesis in wild-type mice and mice with defects in phagosome maturation using a mouse RPE explant model. In explant studies, the levels of β-HB released were temporally correlated with OS phagocytic burst after light onset. In the Mreg-/- mouse where phagosome maturation is delayed, there was a temporal shift in the release of β-HB. An even more pronounced shift in maximal β-HB production was observed in the Abca4-/- RPE, in which loss of the ATP-binding cassette A4 transporter results in defective phagosome processing and accumulation of lipid debris. These studies suggest that FAO and ketogenesis are key to supporting the metabolism of the RPE and preventing the accumulation of lipids that lead to oxidative stress and mitochondrial dysfunction.
Collapse
Affiliation(s)
- Juan Reyes-Reveles
- From the Department of Biochemistry, School of Dental Medicine (SDM), University of Pennsylvania, Philadelphia, Pennsylvania 19104 and
| | - Anuradha Dhingra
- From the Department of Biochemistry, School of Dental Medicine (SDM), University of Pennsylvania, Philadelphia, Pennsylvania 19104 and
| | - Desiree Alexander
- From the Department of Biochemistry, School of Dental Medicine (SDM), University of Pennsylvania, Philadelphia, Pennsylvania 19104 and
| | - Alvina Bragin
- From the Department of Biochemistry, School of Dental Medicine (SDM), University of Pennsylvania, Philadelphia, Pennsylvania 19104 and
| | - Nancy J Philp
- the Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19146
| | - Kathleen Boesze-Battaglia
- From the Department of Biochemistry, School of Dental Medicine (SDM), University of Pennsylvania, Philadelphia, Pennsylvania 19104 and
| |
Collapse
|