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Reynolds RP, Fan RR, Tinajero A, Luo X, Huen SC, Fujikawa T, Lee S, Lemoff A, Mountjoy KG, Elmquist JK. Alpha-melanocyte-stimulating hormone contributes to an anti-inflammatory response to lipopolysaccharide. Mol Metab 2024; 87:101986. [PMID: 38992428 PMCID: PMC11362619 DOI: 10.1016/j.molmet.2024.101986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 06/29/2024] [Accepted: 07/04/2024] [Indexed: 07/13/2024] Open
Abstract
OBJECTIVE During infection, metabolism and immunity react dynamically to promote survival through mechanisms that remain unclear. Pro-opiomelanocortin (POMC) cleavage products are produced and released in the brain and in the pituitary gland. One POMC cleavage product, alpha-melanocyte-stimulating hormone (α-MSH), is known to regulate food intake and energy expenditure and has anti-inflammatory effects. However, it is not known whether α-MSH is required to regulate physiological anti-inflammatory responses. We recently developed a novel mouse model with a targeted mutation in Pomc (Pomctm1/tm1 mice) to block production of all α-MSH forms which are required to regulate metabolism. To test whether endogenous α-MSH is required to regulate immune responses, we compared acute bacterial lipopolysaccharide (LPS)-induced inflammation between Pomctm1/tm1 and wild-type Pomcwt/wt mice. METHODS We challenged 10- to 14-week-old male Pomctm1/tm1 and Pomcwt/wt mice with single i.p. injections of either saline or low-dose LPS (100 μg/kg) and monitored immune and metabolic responses. We used telemetry to measure core body temperature (Tb), ELISA to measure circulating cytokines, corticosterone and α-MSH, and metabolic chambers to measure body weight, food intake, activity, and respiration. We also developed a mass spectrometry method to measure three forms of α-MSH produced in the mouse hypothalamus and pituitary gland. RESULTS LPS induced an exaggerated immune response in Pomctm1/tm1 compared to Pomcwt/wt mice. Both groups of mice were hypoactive and hypothermic following LPS administration, but Pomctm1/tm1 mice were significantly more hypothermic compared to control mice injected with LPS. Pomctm1/tm1 mice also had reduced oxygen consumption and impaired metabolic responses to LPS compared to controls. Pomctm1/tm1 mice had increased levels of key proinflammatory cytokines at 2 h and 4 h post LPS injection compared to Pomcwt/wt mice. Lastly, Pomcwt/wt mice injected with LPS compared to saline had increased total α-MSH in circulation 2 h post injection. CONCLUSIONS Our data indicate endogenous α-MSH contributes to the inflammatory immune responses triggered by low-dose LPS administration and suggest that targeting the melanocortin system could be a potential therapeutic for the treatment of sepsis or inflammatory disease.
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Affiliation(s)
- R P Reynolds
- Department of Internal Medicine, Center for Hypothalamic Research, Dallas, TX, USA
| | - R R Fan
- Department of Internal Medicine, Center for Hypothalamic Research, Dallas, TX, USA
| | - A Tinajero
- Department of Internal Medicine, Center for Hypothalamic Research, Dallas, TX, USA
| | - X Luo
- Department of Biochemistry, Dallas, TX, USA
| | - S C Huen
- Department of Internal Medicine (Nephrology) and Pharmacology, Dallas, TX, USA
| | - T Fujikawa
- Department of Internal Medicine, Center for Hypothalamic Research, Dallas, TX, USA; The Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - S Lee
- Department of Internal Medicine, Center for Hypothalamic Research, Dallas, TX, USA
| | - A Lemoff
- Department of Biochemistry, Dallas, TX, USA
| | - K G Mountjoy
- Department of Molecular Medicine and Pathology, University of Auckland, Private Bag 92019, Auckland 1043, New Zealand
| | - J K Elmquist
- Department of Internal Medicine, Center for Hypothalamic Research, Dallas, TX, USA; The Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Wang B, Jadhav V, Odelade A, Chang E, Chang A, Harrison SH, Maldonado-Devincci AM, Graves JL, Han J. High fat diet reveals sex-specific fecal and liver metabolic alterations in C57BL/6J obese mice. Metabolomics 2023; 19:97. [PMID: 37999907 DOI: 10.1007/s11306-023-02059-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 10/18/2023] [Indexed: 11/25/2023]
Abstract
Obesity is a major health concern that poses significant risks for many other diseases, including diabetes, cardiovascular disease, and cancer. Prevalence of these diseases varies by biological sex. This study utilizes a mouse (C57BL/6J) model of obesity to analyze liver and fecal metabolic profiles at various time points of dietary exposure: 5, 9, and 12 months in control or high fat diet (HFD)-exposed mice. Our study discovered that the female HFD group has a more discernable perturbation and set of significant changes in metabolic profiles than the male HFD group. In the female mice, HFD fecal metabolites including pyruvate, aspartate, and glutamate were lower than control diet-exposed mice after both 9th and 12th month exposure time points, while lactate and alanine were significantly downregulated only at the 12th month. Perturbations of liver metabolic profiles were observed in both male and female HFD groups, compared to controls at the 12th month. Overall, the female HFD group showed higher lactate and glutathione levels compared to controls, while the male HFD group showed higher levels of glutamine and taurine compared to controls. These metabolite-based findings in both fecal and liver samples for a diet-induced effect of obesity may help guide future pioneering discoveries relating to the analysis and prevention of obesity in people, especially for females.
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Affiliation(s)
- Bo Wang
- Department of Chemistry and Chemical Engineering, Florida Institute of Technology, Melbourne, FL, 32901, USA
| | - Vidya Jadhav
- Department of Biology, College of Science and Technology, North Carolina Agricultural and Technical State University, Greensboro, NC, 27411, USA
| | - Anuoluwapo Odelade
- Department of Biology, College of Science and Technology, North Carolina Agricultural and Technical State University, Greensboro, NC, 27411, USA
| | - Evelyn Chang
- Program in Liberal Medical Education, Division of Biology and Medicine, Brown University, Providence, Rhode Island, 02912, USA
| | - Alex Chang
- Department of Animal Science, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY, 14852, USA
| | - Scott H Harrison
- Department of Biology, College of Science and Technology, North Carolina Agricultural and Technical State University, Greensboro, NC, 27411, USA
| | - Antoinette M Maldonado-Devincci
- Department of Psychology, Hairston College of Health and Human Sciences, North Carolina Agricultural and Technical State University, Greensboro, 27411, USA
| | - Joseph L Graves
- Department of Biology, College of Science and Technology, North Carolina Agricultural and Technical State University, Greensboro, NC, 27411, USA
| | - Jian Han
- Department of Biology, College of Science and Technology, North Carolina Agricultural and Technical State University, Greensboro, NC, 27411, USA.
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3
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De Jesus AN, Henry BA. The role of oestrogen in determining sexual dimorphism in energy balance. J Physiol 2023; 601:435-449. [PMID: 36117117 PMCID: PMC10092637 DOI: 10.1113/jp279501] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 07/26/2022] [Indexed: 02/03/2023] Open
Abstract
Energy balance is determined by caloric intake and the rate at which energy is expended, with the latter comprising resting energy expenditure, physical activity and adaptive thermogenesis. The regulation of both energy intake and expenditure exhibits clear sexual dimorphism, with young women being relatively protected against weight gain and the development of cardiometabolic diseases. Preclinical studies have indicated that females are more sensitive to the satiety effects of leptin and insulin compared to males. Furthermore, females have greater thermogenic activity than males, whereas resting energy expenditure is generally higher in males than females. In addition to this, in post-menopausal women, the decline in sex steroid concentration, particularly in oestrogen, is associated with a shift in the distribution of adipose tissue and overall increased propensity to gain weight. Oestrogens are known to regulate energy balance and weight homeostasis via effects on both food intake and energy expenditure. Indeed, 17β-oestradiol treatment increases melanocortin signalling in the hypothalamus to cause satiety. Furthermore, oestrogenic action at the ventromedial hypothalamus has been linked with increased energy expenditure in female mice. We propose that oestrogen action on energy balance is multi-faceted and is fundamental to determining sexual dimorphism in weight control. Furthermore, evidence suggests that the decline in oestrogen levels leads to increased risk of weight gain and development of cardiometabolic disease in women across the menopausal transition.
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Affiliation(s)
- Anne Nicole De Jesus
- Metabolism, Obesity and Diabetes Program, Biomedicine, Discovery Institute, Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Belinda A Henry
- Metabolism, Obesity and Diabetes Program, Biomedicine, Discovery Institute, Department of Physiology, Monash University, Clayton, Victoria, Australia
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4
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VTA MC3R neurons control feeding in an activity- and sex-dependent manner in mice. Neuropharmacology 2021; 197:108746. [PMID: 34371079 DOI: 10.1016/j.neuropharm.2021.108746] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/29/2021] [Accepted: 08/03/2021] [Indexed: 01/25/2023]
Abstract
Increasing evidence indicates that the melanocortin and mesolimbic dopamine (DA) systems interact to regulate feeding and body weight. Because melanocortin-3 receptors (MC3R) are highly expressed in the ventral tegmental area (VTA), we tested whether VTA neurons expressing these receptors (VTA MC3R neurons) control feeding and body weight in vivo. We also tested whether there were sex differences in the ability of VTA MC3R neurons to control feeding, as MC3R -/- mice show sex-dependent alterations in reward feeding and DA levels, and there are clear sex differences in multiple DA-dependent behaviors and disorders. Designer receptors exclusively activated by designer drugs (DREADD) were used to acutely activate and inhibit VTA MC3R neurons and changes in food intake and body weight were measured. Acutely altering the activity of VTA MC3R neurons decreased feeding in an activity- and sex-dependent manner, with acute activation decreasing feeding, but only in females, and acute inhibition decreasing feeding, but only in males. These differences did not appear to be due to sex differences in the number of VTA MC3R neurons, the ability of hM3Dq to activate VTA MC3R neurons, or the proportion of VTA MC3R neurons expressing tyrosine hydroxylase (TH). These studies demonstrate an important role for VTA MC3R neurons in the control of feeding and reveal important sex differences in behavior, whereby opposing changes in neuronal activity in male and female mice cause similar changes in behavior.
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5
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Hsieh YW, Tsai YW, Lai HH, Lai CY, Lin CY, Her GM. Depletion of Alpha-Melanocyte-Stimulating Hormone Induces Insatiable Appetite and Gains in Energy Reserves and Body Weight in Zebrafish. Biomedicines 2021; 9:941. [PMID: 34440144 PMCID: PMC8392443 DOI: 10.3390/biomedicines9080941] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/24/2021] [Accepted: 07/27/2021] [Indexed: 12/23/2022] Open
Abstract
The functions of anorexigenic neurons secreting proopiomelanocortin (POMC)/alpha-melanocyte-stimulating hormone (α-MSH) of the melanocortin system in the hypothalamus in vertebrates are energy homeostasis, food intake, and body weight regulation. However, the mechanisms remain elusive. This article reports on zebrafish that have been genetically engineered to produce α-MSH mutants, α-MSH-7aa and α-MSH-8aa, selectively lacking 7 and 8 amino acids within the α-MSH region, but retaining most of the other normal melanocortin-signaling (Pomc-derived) peptides. The α-MSH mutants exhibited hyperphagic phenotypes leading to body weight gain, as observed in human patients and mammalian models. The actions of several genes regulating appetite in zebrafish are similar to those in mammals when analyzed using gene expression analysis. These include four selected orexigenic genes: Promelanin-concentrating hormone (pmch), agouti-related protein 2 (agrp2), neuropeptide Y (npy), and hypothalamic hypocretin/orexin (hcrt). We also study five selected anorexigenic genes: Brain-derived neurotrophic factor (bdnf), single-minded homolog 1-a (sim1a), corticotropin-releasing hormone b (crhb), thyrotropin-releasing hormone (trh), and prohormone convertase 2 (pcsk2). The orexigenic actions of α-MSH mutants are rescued completely after hindbrain ventricle injection with a synthetic analog of α-MSH and a melanocortin receptor agonist, Melanotan II. We evaluate the adverse effects of MSH depletion on energy balance using the Alamar Blue metabolic rate assay. Our results show that α-MSH is a key regulator of POMC signaling in appetite regulation and energy expenditure, suggesting that it might be a potential therapeutic target for treating human obesity.
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Affiliation(s)
- Yang-Wen Hsieh
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung 202, Taiwan; (Y.-W.H.); (C.-Y.L.); (C.-Y.L.)
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei 112, Taiwan;
| | - Yi-Wen Tsai
- Department of Family Medicine, Chang Gung Memorial Hospital, Keelung 204, Taiwan;
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
| | - Hsin-Hung Lai
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei 112, Taiwan;
| | - Chi-Yu Lai
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung 202, Taiwan; (Y.-W.H.); (C.-Y.L.); (C.-Y.L.)
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei 112, Taiwan;
| | - Chiu-Ya Lin
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung 202, Taiwan; (Y.-W.H.); (C.-Y.L.); (C.-Y.L.)
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei 112, Taiwan;
| | - Guor Mour Her
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei 112, Taiwan;
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Abstract
This paper is the forty-second consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2019 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, 65-30 Kissena Blvd., Flushing, NY, 11367, United States.
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7
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Shakya M, White A, Verchere CB, Low MJ, Lindberg I. Mice lacking PC1/3 expression in POMC-expressing cells do not develop obesity. Endocrinology 2021; 162:6167813. [PMID: 33693631 PMCID: PMC8253230 DOI: 10.1210/endocr/bqab055] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Indexed: 02/06/2023]
Abstract
Pro-opiomelanocortin (POMC) neurons form an integral part of the central melanocortin system regulating food intake and energy expenditure. Genetic and pharmacological studies have revealed that defects in POMC synthesis, processing, and receptor signaling lead to obesity. It is well established that POMC is extensively processed by a series of enzymes, including prohormone convertases PC1/3 and PC2, and that genetic insufficiency of both PC1/3 and POMC is strongly associated with obesity risk. However, whether PC1/3-mediated POMC processing is absolutely tied to body weight regulation is not known. To investigate this question, we generated a Pomc-CreER T2; Pcsk1 lox/lox mouse model in which Pcsk1 is specifically and temporally knocked out in POMC-expressing cells of adult mice by injecting tamoxifen at eight weeks of age. We then measured the impact of Pcsk1 deletion on POMC cleavage to ACTH and α-MSH, and on body weight. In whole pituitary, POMC cleavage was significantly impacted by the loss of Pcsk1, while hypothalamic POMC-derived peptide levels remained similar in all genotypes. However, intact POMC levels were greatly elevated in Pomc-CreER T2; Pcsk1 lox/lox mice. Males expressed two-fold greater levels of pituitary PC1/3 protein than females, consistent with their increased POMC cleavage. Past studies show that mice with germline removal of PC1/3 do not develop obesity, while mice expressing mutant PC1/3 forms do develop obesity. We conclude that obesity pathways are not disrupted by PC1/3 loss solely in POMC-expressing cells, further disfavoring the idea that alterations in POMC processing underlie obesity in PCSK1 deficiency.
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Affiliation(s)
- Manita Shakya
- Department of Anatomy and Neurobiology, University of
Maryland-Baltimore, Baltimore, MD 21201,
USA
| | - Surbhi
- Department of Molecular & Integrative Physiology,
University of Michigan, Ann Arbor, MI
481091, USA
| | - Anne White
- Division of Diabetes, Endocrinology and Gastroenterology,
University of Manchester, Manchester, M13
9PT, United Kingdom
| | - C Bruce Verchere
- Departments of Pathology & Laboratory Medicine and
Surgery, University of British Columbia, British
Columbia, V5Z 4H4, Canada
| | - Malcolm J Low
- Department of Molecular & Integrative Physiology,
University of Michigan, Ann Arbor, MI
481091, USA
| | - Iris Lindberg
- Department of Anatomy and Neurobiology, University of
Maryland-Baltimore, Baltimore, MD 21201,
USA
- Correspondence: Iris Lindberg, PhD,
Department of Anatomy and Neurobiology, 20 Penn St., HSF2, S267, University of
Maryland-Baltimore, Baltimore, MD 21201, USA. E-mail:
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8
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Sun B, Vatanen T, Jayasinghe TN, McKenzie E, Murphy R, O'Sullivan JM. Desacetyl-α-MSH and α-MSH have sex specific interactions with diet to influence mouse gut morphology, metabolites and microbiota. Sci Rep 2020; 10:18957. [PMID: 33144604 PMCID: PMC7641164 DOI: 10.1038/s41598-020-75786-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 10/15/2020] [Indexed: 12/11/2022] Open
Abstract
The melanocortin peptides have an important role in regulating body weight and appetite. Mice that lack the desacetyl-α-MSH and α-MSH peptides (Pomctm1/tm1) develop obesity. This effect is exacerbated by a high fat diet (HFD). However, development of obesity in female Pomctm1/tm1 mice during chronic HFD conditions is not fully accounted for by the increased energy intake. We hypothesized that the protection against chronic HFD-induced obesity imparted by MSH peptides in females is mediated by sex-specific alterations in the gut structure and gut microbiota. We determined that female WT mice had reduced jejunum villus length and increased crypt depth in response to chronic HFD. WT males and Pomctm1/tm1 mice lacked this adaptation to a chronic HFD. Both Pomctm1/tm1 genotype and chronic HFD were significantly associated with gut microbiota composition. Sex-specific associations between Pomctm1/tm1 genotype and gut microbiota were observed in the presence of a chronic HFD. Pomctm1/tm1 females had significantly reduced fecal acetate and propionate concentrations when compared to WT females. We conclude that MSH peptides influence jejunum villus length, crypt depth and the structure of the gut microbiota. These effects favor reduced nutrient absorption and occur in addition to the recognized roles of desacetyl-α-MSH and α-MSH peptides in appetite control.
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Affiliation(s)
- Bo Sun
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Tommi Vatanen
- The Liggins Institute, University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand
| | - Thilini N Jayasinghe
- The Liggins Institute, University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand
| | - Elizabeth McKenzie
- The Liggins Institute, University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand
| | - Rinki Murphy
- School of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
- Department of Medicine, Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand.
| | - Justin M O'Sullivan
- The Liggins Institute, University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand.
- Department of Medicine, Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand.
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9
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Gervais M, Labouèbe G, Picard A, Thorens B, Croizier S. EphrinB1 modulates glutamatergic inputs into POMC-expressing progenitors and controls glucose homeostasis. PLoS Biol 2020; 18:e3000680. [PMID: 33253166 PMCID: PMC7728393 DOI: 10.1371/journal.pbio.3000680] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 12/10/2020] [Accepted: 11/05/2020] [Indexed: 12/25/2022] Open
Abstract
Proopiomelanocortin (POMC) neurons are major regulators of energy balance and glucose homeostasis. In addition to being regulated by hormones and nutrients, POMC neurons are controlled by glutamatergic input originating from multiple brain regions. However, the factors involved in the formation of glutamatergic inputs and how they contribute to bodily functions remain largely unknown. Here, we show that during the development of glutamatergic inputs, POMC neurons exhibit enriched expression of the Efnb1 (EphrinB1) and Efnb2 (EphrinB2) genes, which are known to control excitatory synapse formation. In vivo loss of Efnb1 in POMC-expressing progenitors decreases the amount of glutamatergic inputs, associated with a reduced number of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N-methyl-D-aspartate (NMDA) receptor subunits and excitability of these cells. We found that mice lacking Efnb1 in POMC-expressing progenitors display impaired glucose tolerance due to blunted vagus nerve activity and decreased insulin secretion. However, despite reduced excitatory inputs, mice lacking Efnb2 in POMC-expressing progenitors showed no deregulation of insulin secretion and only mild alterations in feeding behavior and gluconeogenesis. Collectively, our data demonstrate the role of ephrins in controlling excitatory input amount into POMC-expressing progenitors and show an isotype-specific role of ephrins on the regulation of glucose homeostasis and feeding.
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Affiliation(s)
- Manon Gervais
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Gwenaël Labouèbe
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Alexandre Picard
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Bernard Thorens
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Sophie Croizier
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
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10
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Mountjoy KG. ELISA versus LUMINEX assay for measuring mouse metabolic hormones and cytokines: sharing the lessons I have learned. J Immunoassay Immunochem 2020; 42:154-173. [PMID: 33111625 DOI: 10.1080/15321819.2020.1838924] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Enzyme-linked immunosorbent assay (ELISA) has long been the standard for quantitative analysis of metabolic hormones and cytokines. LUMINEX multiplex bead array assays were developed as cost- and time-effective alternatives to ELISA, but they are the only cost- and time-effective if they provide informative data. Here, I show that using half-volume of reagents for an adiponectin single-plex LUMINEX assay and a 6-plex LUMINEX xMAP mouse metabolic bead assay, produces reliable data and increases assay cost-effectiveness. I provide direct comparisons between LUMINEX assay and ELISA for quantitation of mouse leptin and insulin, and evaluate glucagon, GLP-1, IL-6, and TNFα data obtained using the 6-plex LUMINEX assay for a high-fat diet-induced obesity study. Good correlations between assays were obtained for fasting leptin and non-fasting insulin. However, the LUMINEX assay proved unsuitable for quantitating fasting insulin. ELISA proved suitable for quantitating fasting male, but not female, insulin. The LUMINEX assay gave lower values for leptin and higher values for insulin, compared with ELISA. The mouse metabolic LUMINEX assay proved unsuitable for quantitating glucagon, GLP-1, IL-6, and TNFα, due to undetectable levels in most fasting and non-fasting plasma. Overall, quantitative leptin levels were the only reliable data obtained from the mouse metabolic LUMINEX assay.
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Affiliation(s)
- Kathleen G Mountjoy
- Departments of Physiology and Molecular Medicine and Pathology, Faculty of Medical and Health Sciences and Maurice Wilkins Centre for Biodiscovery, University of Auckland, Auckland, New Zealand
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11
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Liu X, Feng X, Deng C, Liu L, Zeng Y, Hu CH. Brown adipose tissue activity is modulated in olanzapine-treated young rats by simvastatin. BMC Pharmacol Toxicol 2020; 21:48. [PMID: 32605639 PMCID: PMC7325271 DOI: 10.1186/s40360-020-00427-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 06/22/2020] [Indexed: 01/07/2023] Open
Abstract
Background Prescription of second-generation antipsychotic drugs (SGAs) to childhood/adolescent has exponentially increased in recent years, which was associated with the greater risk of significant weight gain and dyslipidemia. Statin is considered a potential preventive and treatment approach for reducing SGA-induced weight gain and dyslipidemia in schizophrenia patients. However, the effect of statin treatment in children and adolescents with SGA-induced dyslipidemia is not clearly demonstrated. Methods To investigate the efficacy of statin interventions for reversing SGA-induced dyslipidemia, young Sprague Dawley rats were treated orally with either olanzapine (1.0 mg/kg, t.i.d.), simvastatin (3.0 mg/kg, t.i.d.), olanzapine plus simvastatin (O + S), or vehicle (control) for 5 weeks. Results Olanzapine treatment increased weight gain, food intake and feeding efficiency compared to the control, while O + S co-treatment significantly reversed body weight gain but without significant effects on food intake. Moreover, olanzapine treatment induced a slight but significant reduction in body temperature, with a decrease in locomotor activity. Fasting plasma glucose, triglycerides (TG), and total cholesterol (TC) levels were markedly elevated in the olanzapine-only group, whereas O + S co-treatment significantly ameliorated these changes. Pronounced activation of lipogenic gene expression in the liver and down-regulated expression of uncoupling protein-1 (UCP1) and peroxisome-proliferator-activated receptor-γ co-activator-1α (PGC-1α) in brown adipose tissue (BAT) was observed in the olanzapine-only group. Interestingly, these protein changes could be reversed by co-treatment with O + B. Conclusions Simvastatin is effective in ameliorating TC and TG elevated by olanzapine. Modulation of BAT activity by statins could be a partial mechanism in reducing metabolic side effects caused by SGAs in child and adolescent patients. Graphical abstract ![]()
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Affiliation(s)
- Xuemei Liu
- College of Pharmaceutical Sciences, Medical Research Institute, Southwest University, Chongqing, 400715, PR China.,Engineer Research Center of Chongqing Pharmaceutical Process and Quality Control, Chongqing, 400715, PR China
| | - Xiyu Feng
- College of Pharmaceutical Sciences, Medical Research Institute, Southwest University, Chongqing, 400715, PR China
| | - Chao Deng
- School of Medicine and Molecular Horizons, University of Wollongong, Wollongong, NSW, 2522, Australia.,Antipsychotic Research Laboratory, Illawarra Health and Medical Research Institute, Wollongong, NSW, 2522, Australia
| | - Lu Liu
- College of Pharmaceutical Sciences, Medical Research Institute, Southwest University, Chongqing, 400715, PR China.,North Sichuan Medical College, Nanchong, 637000, PR China
| | - Yanping Zeng
- College of Pharmaceutical Sciences, Medical Research Institute, Southwest University, Chongqing, 400715, PR China
| | - Chang-Hua Hu
- College of Pharmaceutical Sciences, Medical Research Institute, Southwest University, Chongqing, 400715, PR China. .,Engineer Research Center of Chongqing Pharmaceutical Process and Quality Control, Chongqing, 400715, PR China.
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Central administration of β-MSH reduces body weight in obese male Pomc tm1/tm1 mice. Biochim Biophys Acta Gen Subj 2020; 1864:129673. [PMID: 32585252 DOI: 10.1016/j.bbagen.2020.129673] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 05/31/2020] [Accepted: 06/17/2020] [Indexed: 11/21/2022]
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Gavini CK, Cook TM, Rademacher DJ, Mansuy-Aubert V. Hypothalamic C2-domain protein involved in MC4R trafficking and control of energy balance. Metabolism 2020; 102:153990. [PMID: 31666192 DOI: 10.1016/j.metabol.2019.153990] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 09/12/2019] [Accepted: 10/02/2019] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Rates of overweight and obesity epidemic have risen significantly in the past few decades, and 34% of adults and 15-20% of children and adolescents in the United States are now obese. Melanocortin receptor 4 (MC4R), contributes to appetite control in hypothalamic neurons and is a target for future anti-obesity treatments (such as setmelanotide) or novel drug development effort. Proper MC4R trafficking regulation in hypothalamic neurons is crucial for normal neural control of homeostasis and is altered in obesity and in presence of lipids. The mechanisms underlying altered MC4R trafficking in the context of obesity is still unclear. Here, we discovered that C2CD5 expressed in the hypothalamus is involved in the regulation of MC4R endocytosis. This study unmasked a novel trafficking protein nutritionally regulated in the hypothalamus providing a novel target for MC4R dependent pathways involved in bodyweight homeostasis and Obesity. METHODS To evaluate the expression of C2cd5, we first used in situ hybridization and RNAscope technology in combination with electronic microscopy. For in vivo, we characterized the energy balance of wild type (WT) and C2CD5 whole-body knockout (C2CD5KO) mice fed normal chow (NC) and/or western-diet (high-fat/high-sucrose/cholesterol) (WD). To this end, we performed comprehensive longitudinal assessment of bodyweight, energy balance (food intake, energy expenditure, locomotor activity using TSE metabolic cages), and glucose homeostasis. In addition, we evaluated the consequence of loss of C2CD5 on feeding behavior changes normally induced by MC4R agonist (Melanotan, MTII) injection in the paraventricular hypothalamus (PVH). For in vitro approach, we tease out the role of C2CD5 and its calcium sensing domain C2 in MC4R trafficking. We focused on endocytosis of MC4R using an antibody feeding experiment (in a neuronal cell line - Neuro2A (N2A) stably expressing HA-MC4R-GFP; against HA-tag and analyzed by flux cytometry). RESULTS We found that 1) the expression of hypothalamic C2CD5 is decreased in diet-induced obesity models compared to controls, 2) mice lacking C2CD5 exhibit an increase in food intake compared to WT mice, 3) C2CD5 interacts with endocytosis machinery in hypothalamus, 4) loss of functional C2CD5 (lacking C2 domain) blunts MC4R endocytosis in vitro and increases MC4R at the surface that fails to respond to MC4R ligand, and, 5) C2CD5KO mice exhibit decreased acute responses to MTII injection into the PVH. CONCLUSIONS Based on these, we conclude that hypothalamic C2CD5 is involved in MC4R endocytosis and regulate bodyweight homeostasis. These studies suggest that C2CD5 represents a new protein regulated by metabolic cues and involved in metabolic receptor endocytosis. C2CD5 represent a new target and pathway that could be targeted in Obesity.
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Affiliation(s)
- Chaitanya K Gavini
- Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA
| | - Tyler M Cook
- Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA
| | - David J Rademacher
- Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA
| | - Virginie Mansuy-Aubert
- Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA.
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Jarvela TS, Shakya M, Bachor T, White A, Low MJ, Lindberg I. Reduced Stability and pH-Dependent Activity of a Common Obesity-Linked PCSK1 Polymorphism, N221D. Endocrinology 2019; 160:2630-2645. [PMID: 31504391 PMCID: PMC6892424 DOI: 10.1210/en.2019-00418] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 08/26/2019] [Indexed: 02/06/2023]
Abstract
Common mutations in the human prohormone convertase (PC)1/3 gene (PCKSI) are linked to increased risk of obesity. Previous work has shown that the rs6232 single-nucleotide polymorphism (N221D) results in slightly decreased activity, although whether this decrease underlies obesity risk is not clear. We observed significantly decreased activity of the N221D PC1/3 enzyme at the pH of the trans-Golgi network; at this pH, the mutant enzyme was less stable than wild-type enzyme. Recombinant N221D PC1/3 also showed enhanced susceptibility to heat stress. Enhanced susceptibility to tunicamycin-induced endoplasmic reticulum stress was observed in AtT-20/PC2 cell clones in which murine PC1/3 was replaced by human N221D PC1/3, as compared with wild-type human PC1/3. However, N221D PC1/3-expressing AtT-20/PC2 clones processed proopiomelanocortin to α-MSH similarly to wild-type PC1/3. We also generated a CRISPR-edited mouse line expressing the N221D mutation in the PCKSI gene. When homozygous N221D mice were fed either a standard or a high-fat diet, we found no increase in body weight compared with their wild-type sibling controls. Sexual dimorphism was observed in pituitary ACTH for both genotypes, with females exhibiting lower levels of pituitary ACTH. In contrast, hypothalamic α-MSH content for both genotypes was higher in females compared with males. Hypothalamic corticotropin-like intermediate peptide content was higher in wild-type females compared with wild-type, but not N221D, males. Taken together, these data suggest that the increased obesity risk linked to the N221D allele in humans may be due in part to PC1/3-induced loss of resilience to stressors rather than strictly to decreased enzymatic activity on peptide precursors.
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Affiliation(s)
- Timothy S Jarvela
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Surbhi
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
| | - Manita Shakya
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Tomas Bachor
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Anne White
- Division of Diabetes, Endocrinology and Gastroenterology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Malcolm J Low
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
| | - Iris Lindberg
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
- Correspondence: Iris Lindberg, PhD, Department of Anatomy and Neurobiology, University of Maryland School of Medicine, 20 Penn Street, Room S267, Baltimore, Maryland 21210. E-mail:
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Woodruff TK. Words To Work By. Endocrinology 2019; 160:1830-1831. [PMID: 31313821 DOI: 10.1210/en.2019-00481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 06/28/2019] [Indexed: 11/19/2022]
Affiliation(s)
- Teresa K Woodruff
- Department of Obstetrics and Gynecology, Northwestern University, Chicago, Illinois
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