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Blevins JE, Honeycutt MK, Slattery JD, Goldberg M, Rambousek JR, Tsui E, Dodson AD, Shelton KA, Salemeh TS, Elfers CT, Chichura KS, Ashlaw EF, Zraika S, Doyle RP, Roth CL. The novel chimeric multi-agonist peptide (GEP44) reduces energy intake and body weight in male and female diet-induced obese mice in a glucagon-like peptide-1 receptor-dependent manner. Front Endocrinol (Lausanne) 2024; 15:1432928. [PMID: 39104812 PMCID: PMC11298355 DOI: 10.3389/fendo.2024.1432928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2024] [Accepted: 06/25/2024] [Indexed: 08/07/2024] Open
Abstract
We recently reported that a novel chimeric peptide (GEP44) targeting both the glucagon-like peptide-1 receptor (GLP-1R) and neuropeptide Y1- and Y2 receptor (Y1R and Y2R) reduced energy intake and body weight (BW) in diet-induced obese (DIO) rats. We hypothesized that GEP44 reduces energy intake and BW primarily through a GLP-1R dependent mechanism. To test this hypothesis, GLP-1R+/+ mice and GLP-1R null (GLP-1R-/-) mice were fed a high fat diet for 4 months to elicit diet-induced obesity prior to undergoing a sequential 3-day vehicle period, 3-day drug treatment (5, 10, 20 or 50 nmol/kg; GEP44 vs the selective GLP-1R agonist, exendin-4) and a 3-day washout. Energy intake, BW, core temperature and activity were measured daily. GEP44 (10, 20 and 50 nmol/kg) reduced BW after 3-day treatment in DIO male GLP-1R+/+ mice by -1.5 ± 0.6, -1.3 ± 0.4 and -1.9 ± 0.4 grams, respectively (P<0.05), with similar effects being observed in female GLP-1R+/+ mice. These effects were absent in male and female DIO GLP-1R-/- mice suggesting that GLP-1R signaling contributes to GEP44-elicited reduction of BW. Further, GEP44 decreased energy intake in both male and female DIO GLP-1R+/+ mice, but GEP44 appeared to produce more consistent effects across multiple doses in males. In GLP-1R-/- mice, the effects of GEP44 on energy intake were only observed in males and not females, suggesting that GEP44 may reduce energy intake, in part, through a GLP-1R independent mechanism in males. In addition, GEP44 reduced core temperature and activity in both male and female GLP-1R+/+ mice suggesting that it may also reduce energy expenditure. Lastly, we show that GEP44 reduced fasting blood glucose in DIO male and female mice through GLP-1R. Together, these findings support the hypothesis that the chimeric peptide, GEP44, reduces energy intake, BW, core temperature, and glucose levels in male and female DIO mice primarily through a GLP-1R dependent mechanism.
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Affiliation(s)
- James E. Blevins
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
| | - Mackenzie K. Honeycutt
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - Jared D. Slattery
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - Matvey Goldberg
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - June R. Rambousek
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - Edison Tsui
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - Andrew D. Dodson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - Kyra A. Shelton
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | | | | | - Kylie S. Chichura
- Department of Chemistry, Syracuse University, Syracuse, NY, United States
| | - Emily F. Ashlaw
- Department of Chemistry, Syracuse University, Syracuse, NY, United States
| | - Sakeneh Zraika
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
| | - Robert P. Doyle
- Department of Chemistry, Syracuse University, Syracuse, NY, United States
- Departments of Medicine and Pharmacology, State University of New York (SUNY) Upstate Medical University, Syracuse, NY, United States
| | - Christian L. Roth
- Seattle Children’s Research Institute, Seattle, WA, United States
- Department of Pediatrics, University of Washington School of Medicine, Seattle, WA, United States
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Rea JJ, Liu CM, Hayes AMR, Bashaw AG, Schwartz G, Ohan R, Décarie-Spain L, Kao AE, Klug ME, Phung KJ, Waldow AI, Wood RI, Kanoski SE. Hippocampus oxytocin signaling promotes prosocial eating in rats. Biol Psychiatry 2024:S0006-3223(24)01462-8. [PMID: 39038641 DOI: 10.1016/j.biopsych.2024.07.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 07/07/2024] [Accepted: 07/12/2024] [Indexed: 07/24/2024]
Abstract
BACKGROUND Oxytocin (OT) is a hypothalamic neuropeptide involved in diverse physiological and behavioral functions, including social-based behavior and food intake control. The extent that OT's role in regulating these two fundamental behaviors is interconnected is unknown and is a critical gap given that social factors have a strong influence on eating behavior in mammals. Here we focus on OT signaling in the dorsal hippocampus (HPCd), a brain region recently linked with eating and social memory, as a candidate system where these functions overlap. METHODS HPCd OT signaling gain- and loss-of-function strategies were employed in male Sprague-Dawley rats that were trained in a novel social eating procedure to consume their first nocturnal meal under conditions that vary with regards to conspecific presence and familiarity. The endogenous role of HPCd OT signaling was also evaluated for olfactory-based social transmission of food preference learning, sociality, and social recognition memory. RESULTS HPCd OT administration had no effect on food intake under isolated conditions, yet significantly increased consumption in the presence of a familiar, but not an unfamiliar conspecific. Supporting these results, chronic knockdown of HPCd OT receptor expression eliminated the food intake-promoting effects of a familiar conspecific. HPCd OT receptor knockdown also blocked social transmission of food preference learning and impaired social recognition memory without affecting sociality. CONCLUSION Collective results identify endogenous HPCd OT signaling as a novel substrate where OT synergistically influences eating and social behaviors, including the social facilitation of eating and the social transmission of food preference.
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Affiliation(s)
- Jessica J Rea
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA; Neuroscience Graduate Program, University of Southern California, USA
| | - Clarissa M Liu
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA; Neuroscience Graduate Program, University of Southern California, USA
| | - Anna M R Hayes
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA
| | - Alexander G Bashaw
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA; Neuroscience Graduate Program, University of Southern California, USA
| | - Grace Schwartz
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA
| | - Rita Ohan
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA
| | - Léa Décarie-Spain
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA
| | - Alicia E Kao
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA
| | - Molly E Klug
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA
| | - Kenneth J Phung
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA
| | - Alice I Waldow
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA
| | - Ruth I Wood
- Neuroscience Graduate Program, University of Southern California, USA; Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, USA
| | - Scott E Kanoski
- Human and Evolutionary Biology Section, Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, USA; Neuroscience Graduate Program, University of Southern California, USA.
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Edwards MM, Nguyen HK, Dodson AD, Herbertson AJ, Wolden-Hanson T, Wietecha T, Honeycutt MK, Slattery JD, O'Brien KD, Graham JL, Havel PJ, Mundinger TO, Sikkema C, Peskind ER, Ryu V, Taborsky GJ, Blevins JE. Sympathetic innervation of interscapular brown adipose tissue is not a predominant mediator of oxytocin-elicited reductions of body weight and adiposity in male diet-induced obese mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.29.596425. [PMID: 38854021 PMCID: PMC11160755 DOI: 10.1101/2024.05.29.596425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Previous studies indicate that CNS administration of oxytocin (OT) reduces body weight in high fat diet-induced obese (DIO) rodents by reducing food intake and increasing energy expenditure (EE). We recently demonstrated that hindbrain (fourth ventricular [4V]) administration of OT elicits weight loss and elevates interscapular brown adipose tissue temperature (T IBAT , a surrogate measure of increased EE) in DIO mice. What remains unclear is whether OT-elicited weight loss requires increased sympathetic nervous system (SNS) outflow to IBAT. We hypothesized that OT-induced stimulation of SNS outflow to IBAT contributes to its ability to activate BAT and elicit weight loss in DIO mice. To test this hypothesis, we determined the effect of disrupting SNS activation of IBAT on the ability of 4V OT administration to increase T IBAT and elicit weight loss in DIO mice. We first determined whether bilateral surgical SNS denervation to IBAT was successful as noted by ≥ 60% reduction in IBAT norepinephrine (NE) content in DIO mice. NE content was selectively reduced in IBAT at 1-, 6- and 7-weeks post-denervation by 95.9±2.0, 77.4±12.7 and 93.6±4.6% ( P <0.05), respectively and was unchanged in inguinal white adipose tissue, pancreas or liver. We subsequently measured the effects of acute 4V OT (1, 5 µg ≈ 0.99, 4.96 nmol) on T IBAT in DIO mice following sham or bilateral surgical SNS denervation to IBAT. We found that the high dose of 4V OT (5 µg ≈ 4.96 nmol) elevated T IBAT similarly in sham mice as in denervated mice. We subsequently measured the effects of chronic 4V OT (16 nmol/day over 29 days) or vehicle infusions on body weight, adiposity and food intake in DIO mice following sham or bilateral surgical denervation of IBAT. Chronic 4V OT reduced body weight by 5.7±2.23% and 6.6±1.4% in sham and denervated mice ( P <0.05), respectively, and this effect was similar between groups ( P =NS). OT produced corresponding reductions in whole body fat mass ( P <0.05). Together, these findings support the hypothesis that sympathetic innervation of IBAT is not necessary for OT-elicited increases in BAT thermogenesis and reductions of body weight and adiposity in male DIO mice.
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Blevins JE, Honeycutt MK, Slattery JD, Goldberg M, Rambousek JR, Tsui E, Dodson AD, Shelton KA, Salemeh TS, Elfers CT, Chichura KS, Ashlaw EF, Zraika S, Doyle RP, Roth CL. The Novel Chimeric Multi-Agonist Peptide (GEP44) Reduces Energy Intake and Body Weight in Male and Female Diet-Induced Obese Mice in a Glucagon-Like Peptide-1 Receptor-Dependent Manner. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.17.594690. [PMID: 38826286 PMCID: PMC11142068 DOI: 10.1101/2024.05.17.594690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
We recently reported that a novel chimeric peptide (GEP44) targeting both the glucagon-like peptide-1 receptor (GLP-1R) and neuropeptide Y1- and Y2 receptor (Y1R and Y2R) reduced energy intake and body weight (BW) in diet-induced obese (DIO) rats. We hypothesized that GEP44 reduces energy intake and BW primarily through a GLP-1R dependent mechanism. To test this hypothesis, GLP-1R +/+ mice and GLP-1R null (GLP-1R -/- ) mice were fed a high fat diet for 4 months to elicit diet-induced obesity prior to undergoing a sequential 3-day vehicle period, 3-day drug treatment (5, 10, 20 or 50 nmol/kg; GEP44 vs the selective GLP-1R agonist, exendin-4) and a 3-day washout. Energy intake, BW, core temperature and activity were measured daily. GEP44 (10, 20 and 50 nmol/kg) reduced BW after 3-day treatment in DIO male GLP-1R +/+ mice by - 1.5±0.6, -1.3±0.4 and -1.9±0.4 grams, respectively ( P <0.05), with similar effects being observed in female GLP-1R +/+ mice. These effects were absent in male and female DIO GLP-1R -/- mice suggesting that GLP-1R signaling contributes to GEP44-elicited reduction of BW. Further, GEP44 decreased energy intake in both male and female DIO GLP-1R +/+ mice, but GEP44 appeared to produce more consistent effects across multiple doses in males. In GLP-1R -/- mice, the effects of GEP44 on energy intake were only observed in males and not females, suggesting that GEP44 may reduce energy intake, in part, through a GLP-1R independent mechanism in males. In addition, GEP44 reduced core temperature and activity in both male and female GLP-1R +/+ mice suggesting that it may also reduce energy expenditure. Lastly, we show that GEP44 reduced fasting blood glucose in DIO male and female mice through GLP-1R. Together, these findings support the hypothesis that the chimeric peptide, GEP44, reduces energy intake, BW, core temperature, and glucose levels in male and female DIO mice primarily through a GLP-1R dependent mechanism.
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Yamamoto S, Arakaki R, Noguchi H, Takeda A, Uchishiba M, Kamada S, Mineda A, Kon M, Kawakita T, Kinouchi R, Yamamoto Y, Yoshida K, Shinohara N, Iwasa T. New discoveries on the interaction between testosterone and oxytocin in male rats - Testosterone-mediated effects of oxytocin in the prevention of obesity. Physiol Behav 2023; 266:114199. [PMID: 37062515 DOI: 10.1016/j.physbeh.2023.114199] [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: 02/24/2023] [Revised: 04/03/2023] [Accepted: 04/14/2023] [Indexed: 04/18/2023]
Abstract
Sex steroid hormones are important for the maintenance of metabolism in both sexes. Oxytocin (OT) is a neuropeptide that is synthesized in hypothalamic regions, secreted from the posterior lobe of the pituitary gland, and is involved in the control of appetite, body weight, and metabolism. Estrogen and OT both play a role in the metabolism of nutrients, and OT has potential in the prevention of obesity. However, the relationship between testosterone and OT remains unclear. Therefore, the present study investigated the relationship between testosterone and OT in hypogonadal male rats and male rats receiving testosterone replacement therapy. The results obtained showed that testosterone increased serum OT levels and promoted the secretion of adiponectin from visceral fat, and reduced body fat directly and/or indirectly through OT and adiponectin. Testosterone also increased the expression of OT receptors in the hypothalamus to increase sensitivity to OT, and perhaps because of this, OT administration had the effect of reducing food intake and body weight gain in both normal and castrated rats, and this effect was stronger in normal rats. In other words, the preventative effects of OT on obesity may be synergistic with testosterone. Collectively, the present results indicate that testosterone exerts indirect effects to prevent obesity and atherosclerosis through OT and adiponectin. In conclusion, testosterone replacement therapy is useful for preventing obesity caused by hypogonadism, and OT has potential in supportive medicine to prevent obesity and adult diseases.
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Affiliation(s)
- Shota Yamamoto
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan; Department of Renal and Genitourinary Surgery, Graduate School of Medicine, Hokkaido University, Sapporo 060-0808, Japan
| | - Ryosuke Arakaki
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan
| | - Hiroki Noguchi
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan
| | - Asuka Takeda
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan
| | - Maimi Uchishiba
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan
| | - Shuhei Kamada
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan
| | - Ayuka Mineda
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan
| | - Masafumi Kon
- Department of Renal and Genitourinary Surgery, Graduate School of Medicine, Hokkaido University, Sapporo 060-0808, Japan
| | - Takako Kawakita
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan
| | - Riyo Kinouchi
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan
| | - Yuri Yamamoto
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan
| | - Kanako Yoshida
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan
| | - Nobuo Shinohara
- Department of Renal and Genitourinary Surgery, Graduate School of Medicine, Hokkaido University, Sapporo 060-0808, Japan
| | - Takeshi Iwasa
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Graduate School, Tokushima University, Tokushima 770-8501, Japan.
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Asker M, Krieger JP, Liles A, Tinsley IC, Borner T, Maric I, Doebley S, Furst CD, Börchers S, Longo F, Bhat YR, De Jonghe BC, Hayes MR, Doyle RP, Skibicka KP. Peripherally restricted oxytocin is sufficient to reduce food intake and motivation, while CNS entry is required for locomotor and taste avoidance effects. Diabetes Obes Metab 2023; 25:856-877. [PMID: 36495318 PMCID: PMC9987651 DOI: 10.1111/dom.14937] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 11/21/2022] [Accepted: 12/02/2022] [Indexed: 12/14/2022]
Abstract
OBJECTIVES Oxytocin (OT) has a well-established role in reproductive behaviours; however, it recently emerged as an important regulator of energy homeostasis. In addition to central nervous system (CNS), OT is found in the plasma and OT receptors (OT-R) are found in peripheral tissues relevant to energy balance regulation. Here, we aim to determine whether peripheral OT-R activation is sufficient to alter energy intake and expenditure. METHODS AND RESULTS We first show that systemic OT potently reduced food intake and food-motivated behaviour for a high-fat reward in male and female rats. As it is plausible that peripherally, intraperitoneally (IP) injected OT crosses the blood-brain barrier (BBB) to produce some of the metabolic effects within the CNS, we screened, with a novel fluorescently labelled-OT (fAF546-OT, Roxy), for the presence of IP-injected Roxy in CNS tissue relevant to feeding control and compared such with BBB-impermeable fluorescent OT-B12 (fCy5-OT-B12; BRoxy). While Roxy did penetrate the CNS, BRoxy did not. To evaluate the behavioural and thermoregulatory impact of exclusive activation of peripheral OT-R, we generated a novel BBB-impermeable OT (OT-B12 ), with equipotent binding at OT-R in vitro. In vivo, IP-injected OT and OT-B12 were equipotent at food intake suppression in rats of both sexes, suggesting that peripheral OT acts on peripheral OT-R to reduce feeding behaviour. Importantly, OT induced a potent conditioned taste avoidance, indistinguishable from that induced by LiCl, when applied peripherally. Remarkably, and in contrast to OT, OT-B12 did not induce any conditioned taste avoidance. Limiting the CNS entry of OT also resulted in a dose-dependent reduction of emesis in male shrews. While both OT and OT-B12 proved to have similar effects on body temperature, only OT resulted in home-cage locomotor depression. CONCLUSIONS Together our data indicate that limiting systemic OT CNS penetrance preserves the anorexic effects of the peptide and reduces the clinically undesired side effects of OT: emesis, taste avoidance and locomotor depression. Thus, therapeutic targeting of peripheral OT-R may be a viable strategy to achieve appetite suppression with better patient outcomes.
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Affiliation(s)
- Mohammed Asker
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Wallenberg Centre for molecular and translational medicine, University of Gothenburg, Gothenburg, Sweden
| | - Jean-Philippe Krieger
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Amber Liles
- Department of Chemistry, Syracuse University, Syracuse, New York, USA
| | - Ian C Tinsley
- Department of Chemistry, Syracuse University, Syracuse, New York, USA
| | - Tito Borner
- Department of Biobehavioral Health Sciences, University of Pennsylvania, School of Nursing, Philadelphia, Pennsylvania, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ivana Maric
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Department of Chemistry, Syracuse University, Syracuse, New York, USA
- Department of Nutritional Sciences, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Sarah Doebley
- Department of Biobehavioral Health Sciences, University of Pennsylvania, School of Nursing, Philadelphia, Pennsylvania, USA
| | - C Daniel Furst
- Department of Biobehavioral Health Sciences, University of Pennsylvania, School of Nursing, Philadelphia, Pennsylvania, USA
| | - Stina Börchers
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Wallenberg Centre for molecular and translational medicine, University of Gothenburg, Gothenburg, Sweden
| | - Francesco Longo
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Yashaswini R Bhat
- Department of Nutritional Sciences, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Bart C De Jonghe
- Department of Biobehavioral Health Sciences, University of Pennsylvania, School of Nursing, Philadelphia, Pennsylvania, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Matthew R Hayes
- Department of Biobehavioral Health Sciences, University of Pennsylvania, School of Nursing, Philadelphia, Pennsylvania, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Robert P Doyle
- Department of Chemistry, Syracuse University, Syracuse, New York, USA
- Departments of Medicine and Pharmacology, State University of New York, Upstate Medical University, Syracuse, New York, USA
| | - Karolina P Skibicka
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Wallenberg Centre for molecular and translational medicine, University of Gothenburg, Gothenburg, Sweden
- Department of Nutritional Sciences, Pennsylvania State University, University Park, Pennsylvania, USA
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Zayan U, Caccialupi Da Prato L, Muscatelli F, Matarazzo V. Modulation of the thermosensory system by oxytocin. Front Mol Neurosci 2023; 15:1075305. [PMID: 36698777 PMCID: PMC9868264 DOI: 10.3389/fnmol.2022.1075305] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 12/06/2022] [Indexed: 01/11/2023] Open
Abstract
Oxytocin (OT) is a neurohormone involved early in neurodevelopment and is implicated in multiple functions, including sensory modulation. Evidence of such modulation has been observed for different sensory modalities in both healthy and pathological conditions. This review summarizes the pleiotropic modulation that OT can exercise on an often overlooked sensory system: thermosensation. This system allows us to sense temperature variations and compensate for the variation to maintain a stable core body temperature. Oxytocin modulates autonomic and behavioral mechanisms underlying thermoregulation at both central and peripheral levels. Hyposensitivity or hypersensitivity for different sensory modalities, including thermosensitivity, is a common feature in autism spectrum disorder (ASD), recapitulated in several ASD mouse models. These sensory dysregulations occur early in post-natal development and are correlated with dysregulation of the oxytocinergic system. In this study, we discussed the potential link between thermosensory atypia and the dysregulation of the oxytocinergic system in ASD.
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Tsingotjidou AS. Oxytocin: A Multi-Functional Biomolecule with Potential Actions in Dysfunctional Conditions; From Animal Studies and Beyond. Biomolecules 2022; 12:1603. [PMID: 36358953 PMCID: PMC9687803 DOI: 10.3390/biom12111603] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 10/20/2022] [Accepted: 10/23/2022] [Indexed: 10/13/2023] Open
Abstract
Oxytocin is a hormone secreted from definite neuroendocrine neurons located in specific nuclei in the hypothalamus (mainly from paraventricular and supraoptic nuclei), and its main known function is the contraction of uterine and/or mammary gland cells responsible for parturition and breastfeeding. Among the actions of the peripherally secreted oxytocin is the prevention of different degenerative disorders. These actions have been proven in cell culture and in animal models or have been tested in humans based on hypotheses from previous studies. This review presents the knowledge gained from the previous studies, displays the results from oxytocin intervention and/or treatment and proposes that the well described actions of oxytocin might be connected to other numerous, diverse actions of the biomolecule.
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Affiliation(s)
- Anastasia S Tsingotjidou
- Laboratory of Anatomy, Histology and Embryology, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54 124 Thessaloniki, Greece
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9
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Fukushima A, Kataoka N, Nakamura K. An oxytocinergic neural pathway that stimulates thermogenic and cardiac sympathetic outflow. Cell Rep 2022; 40:111380. [PMID: 36130511 DOI: 10.1016/j.celrep.2022.111380] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 03/29/2022] [Accepted: 08/28/2022] [Indexed: 11/17/2022] Open
Abstract
Oxytocin alters autonomic functions besides social behaviors. However, the central neuronal links between hypothalamic oxytocinergic neurons and the autonomic nervous system remain unclear. Here we show that oxytocinergic neurons in the rat paraventricular hypothalamic nucleus (PVH), a pivotal site for energy homeostasis, innervate sympathetic premotor neurons in the rostral medullary raphe region (rMR) to stimulate brown adipose tissue (BAT) thermogenesis and cardiovascular functions. Oxytocin receptor stimulation in the rMR evokes BAT thermogenesis and tachycardia. In vivo optogenetic stimulation of the PVH→rMR long-range oxytocinergic pathway, using a virus-mediated system for amplified gene expression in oxytocinergic neurons, not only elicits BAT thermogenic and cardiac responses but also potentiates sympathetic responses evoked by glutamatergic transmission in the rMR. The PVH→rMR oxytocinergic pathway connects the hypothalamic circuit for energy homeostasis to thermogenic and cardiac sympathetic outflow, and, therefore, its defects may cause obesity and impaired thermoregulation, as seen in Prader-Willi syndrome.
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Affiliation(s)
- Akihiro Fukushima
- Department of Integrative Physiology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Naoya Kataoka
- Department of Integrative Physiology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan; Nagoya University Institute for Advanced Research, Nagoya 464-8601, Japan
| | - Kazuhiro Nakamura
- Department of Integrative Physiology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan.
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10
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Olszewski PK, Noble EE, Paiva L, Ueta Y, Blevins JE. Oxytocin as a potential pharmacological tool to combat obesity. J Neuroendocrinol 2022; 34:e13106. [PMID: 35192207 PMCID: PMC9372234 DOI: 10.1111/jne.13106] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 02/06/2022] [Accepted: 02/08/2022] [Indexed: 11/30/2022]
Abstract
The neuropeptide oxytocin (OT) has emerged as an important anorexigen in the regulation of food intake and energy balance. It has been shown that the release of OT and activation of hypothalamic OT neurons coincide with food ingestion. Its effects on feeding have largely been attributed to limiting meal size through interactions in key regulatory brain regions governing the homeostatic control of food intake such as the hypothalamus and hindbrain in addition to key feeding reward areas such as the nucleus accumbens and ventral tegmental area. Furthermore, the magnitude of an anorexigenic response to OT and feeding-related activation of the brain OT circuit are modified by the composition and flavor of a diet, as well as by a social context in which a meal is consumed. OT is particularly effective in reducing consumption of carbohydrates and sweet tastants. Pharmacologic, genetic, and pair-feeding studies indicate that OT-elicited weight loss cannot be fully explained by reductions of food intake and that the overall impact of OT on energy balance is also partly a result of OT-elicited changes in lipolysis, energy expenditure, and glucose regulation. Peripheral administration of OT mimics many of its effects when it is given into the central nervous system, raising the questions of whether and to what extent circulating OT acts through peripheral OT receptors to regulate energy balance. Although OT has been found to elicit weight loss in female mice, recent studies have indicated that sex and estrous cycle may impact oxytocinergic modulation of food intake. Despite the overall promising basic research data, attempts to use OT in the clinical setting to combat obesity and overeating have generated somewhat mixed results. The focus of this mini-review is to briefly summarize the role of OT in feeding and metabolism, address gaps and inconsistencies in our knowledge, and discuss some of the limitations to the potential use of chronic OT that should help guide future research on OT as a tailor-made anti-obesity therapeutic.
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Affiliation(s)
- Pawel K Olszewski
- Faculty of Science and Engineering, University of Waikato, Waikato, New Zealand
- Department of Food Science and Nutrition, College of Food, Agricultural and Natural Resource Sciences, University of Minnesota, St Paul, Minnesota, USA
- Department of Integrative Biology and Physiology, Medical School, University of Minnesota, Minneapolis, Minnesota, USA
| | - Emily E Noble
- Department of Nutritional Sciences, University of Georgia, Athens, Georgia, USA
| | - Luis Paiva
- Instituto de Ciencia Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
| | - Yoichi Ueta
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Fukuoka, Japan
| | - James E Blevins
- Department of Veterans Affairs Medical Center, VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Seattle, Washington, USA
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, Washington, USA
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11
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Changes in Endogenous Oxytocin Levels and the Effects of Exogenous Oxytocin Administration on Body Weight Changes and Food Intake in Polycystic Ovary Syndrome Model Rats. Int J Mol Sci 2022; 23:ijms23158207. [PMID: 35897783 PMCID: PMC9330807 DOI: 10.3390/ijms23158207] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 07/24/2022] [Accepted: 07/24/2022] [Indexed: 12/10/2022] Open
Abstract
Polycystic ovary syndrome (PCOS) is frequently seen in females of reproductive age and is associated with metabolic disorders that are exacerbated by obesity. Although body weight reduction programs via diet and lifestyle changes are recommended for modifying reproductive and metabolic phenotypes, the drop-out rate is high. Thus, an efficacious, safe, and continuable treatment method is needed. Recent studies have shown that oxytocin (OT) reduces body weight gain and food intake, and promotes lipolysis in some mammals, including humans (especially obese individuals), without any adverse effects. In the present study, we evaluated the changes in endogenous OT levels, and the effects of acute and chronic OT administration on body weight changes, food intake, and fat mass using novel dihydrotestosterone-induced PCOS model rats. We found that the serum OT level was lower in PCOS model rats than in control rats, whereas the hypothalamic OT mRNA expression level did not differ between them. Acute intraperitoneal administration of OT during the dark phase reduced the body weight gain and food intake in PCOS model rats, but these effects were not observed in control rats. In contrast, chronic administration of OT decreased the food intake in both the PCOS model rats and control rats. These findings indicate that OT may be a candidate medicine that is efficacious, safe, and continuable for treating obese PCOS patients.
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12
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Goh KK, Chen CYA, Wu TH, Chen CH, Lu ML. Crosstalk between Schizophrenia and Metabolic Syndrome: The Role of Oxytocinergic Dysfunction. Int J Mol Sci 2022; 23:ijms23137092. [PMID: 35806096 PMCID: PMC9266532 DOI: 10.3390/ijms23137092] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/23/2022] [Accepted: 06/23/2022] [Indexed: 02/01/2023] Open
Abstract
The high prevalence of metabolic syndrome in persons with schizophrenia has spurred investigational efforts to study the mechanism beneath its pathophysiology. Early psychosis dysfunction is present across multiple organ systems. On this account, schizophrenia may be a multisystem disorder in which one organ system is predominantly affected and where other organ systems are also concurrently involved. Growing evidence of the overlapping neurobiological profiles of metabolic risk factors and psychiatric symptoms, such as an association with cognitive dysfunction, altered autonomic nervous system regulation, desynchrony in the resting-state default mode network, and shared genetic liability, suggest that metabolic syndrome and schizophrenia are connected via common pathways that are central to schizophrenia pathogenesis, which may be underpinned by oxytocin system dysfunction. Oxytocin, a hormone that involves in the mechanisms of food intake and metabolic homeostasis, may partly explain this piece of the puzzle in the mechanism underlying this association. Given its prosocial and anorexigenic properties, oxytocin has been administered intranasally to investigate its therapeutic potential in schizophrenia and obesity. Although the pathophysiology and mechanisms of oxytocinergic dysfunction in metabolic syndrome and schizophrenia are both complex and it is still too early to draw a conclusion upon, oxytocinergic dysfunction may yield a new mechanistic insight into schizophrenia pathogenesis and treatment.
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Affiliation(s)
- Kah Kheng Goh
- Department of Psychiatry, Wan-Fang Hospital, Taipei Medical University, Taipei 116, Taiwan; (K.K.G.); (C.Y.-A.C.); (C.-H.C.)
- Psychiatric Research Center, Wan-Fang Hospital, Taipei Medical University, Taipei 116, Taiwan;
- Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
| | - Cynthia Yi-An Chen
- Department of Psychiatry, Wan-Fang Hospital, Taipei Medical University, Taipei 116, Taiwan; (K.K.G.); (C.Y.-A.C.); (C.-H.C.)
- Psychiatric Research Center, Wan-Fang Hospital, Taipei Medical University, Taipei 116, Taiwan;
| | - Tzu-Hua Wu
- Psychiatric Research Center, Wan-Fang Hospital, Taipei Medical University, Taipei 116, Taiwan;
- Department of Clinical Pharmacy, School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan
| | - Chun-Hsin Chen
- Department of Psychiatry, Wan-Fang Hospital, Taipei Medical University, Taipei 116, Taiwan; (K.K.G.); (C.Y.-A.C.); (C.-H.C.)
- Psychiatric Research Center, Wan-Fang Hospital, Taipei Medical University, Taipei 116, Taiwan;
- Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
| | - Mong-Liang Lu
- Department of Psychiatry, Wan-Fang Hospital, Taipei Medical University, Taipei 116, Taiwan; (K.K.G.); (C.Y.-A.C.); (C.-H.C.)
- Psychiatric Research Center, Wan-Fang Hospital, Taipei Medical University, Taipei 116, Taiwan;
- Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
- Correspondence:
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13
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Niu J, Tong J, Blevins JE. Oxytocin as an Anti-obesity Treatment. Front Neurosci 2021; 15:743546. [PMID: 34720864 PMCID: PMC8549820 DOI: 10.3389/fnins.2021.743546] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 09/16/2021] [Indexed: 12/19/2022] Open
Abstract
Obesity is a growing health concern, as it increases risk for heart disease, hypertension, type 2 diabetes, cancer, COVID-19 related hospitalizations and mortality. However, current weight loss therapies are often associated with psychiatric or cardiovascular side effects or poor tolerability that limit their long-term use. The hypothalamic neuropeptide, oxytocin (OT), mediates a wide range of physiologic actions, which include reproductive behavior, formation of prosocial behaviors and control of body weight. We and others have shown that OT circumvents leptin resistance and elicits weight loss in diet-induced obese rodents and non-human primates by reducing both food intake and increasing energy expenditure (EE). Chronic intranasal OT also elicits promising effects on weight loss in obese humans. This review evaluates the potential use of OT as a therapeutic strategy to treat obesity in rodents, non-human primates, and humans, and identifies potential mechanisms that mediate this effect.
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Affiliation(s)
- JingJing Niu
- VA Puget Sound Health Care System, Office of Research and Development, Medical Research Service, Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States.,Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
| | - Jenny Tong
- VA Puget Sound Health Care System, Office of Research and Development, Medical Research Service, Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States.,Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
| | - James E Blevins
- VA Puget Sound Health Care System, Office of Research and Development, Medical Research Service, Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States.,Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
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14
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Anekonda VT, Thompson BW, Ho JM, Roberts ZS, Edwards MM, Nguyen HK, Dodson AD, Wolden-Hanson T, Chukri DW, Herbertson AJ, Graham JL, Havel PJ, Wietecha TA, O’Brien KD, Blevins JE. Hindbrain Administration of Oxytocin Reduces Food Intake, Weight Gain and Activates Catecholamine Neurons in the Hindbrain Nucleus of the Solitary Tract in Rats. J Clin Med 2021; 10:5078. [PMID: 34768597 PMCID: PMC8584350 DOI: 10.3390/jcm10215078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 11/16/2022] Open
Abstract
Existing studies show that CNS oxytocin (OT) signaling is important in the control of energy balance, but it is unclear which neurons may contribute to these effects. Our goals were to examine (1) the dose-response effects of acute OT administration into the third (3V; forebrain) and fourth (4V; hindbrain) ventricles to assess sensitivity to OT in forebrain and hindbrain sites, (2) the extent to which chronic 4V administration of OT reduces weight gain associated with the progression of diet-induced obesity, and (3) whether nucleus tractus solitarius (NTS) catecholamine neurons are downstream targets of 4V OT. Initially, we examined the dose-response effects of 3V and 4V OT (0.04, 0.2, 1, or 5 μg). 3V and 4V OT (5 μg) suppressed 0.5-h food intake by 71.7 ± 6.0% and 60 ± 12.9%, respectively. 4V OT (0.04, 0.2, 1 μg) reduced food intake by 30.9 ± 12.9, 42.1 ± 9.4, and 56.4 ± 9.0%, respectively, whereas 3V administration of OT (1 μg) was only effective at reducing 0.5-h food intake by 38.3 ± 10.9%. We subsequently found that chronic 4V OT infusion, as with chronic 3V infusion, reduced body weight gain (specific to fat mass) and tended to reduce plasma leptin in high-fat diet (HFD)-fed rats, in part, through a reduction in energy intake. Lastly, we determined that 4V OT increased the number of hindbrain caudal NTS Fos (+) neurons (156 ± 25) relative to vehicle (12 ± 3). The 4V OT also induced Fos in tyrosine hydroxylase (TH; marker of catecholamine neurons) (+) neurons (25 ± 7%) relative to vehicle (0.8 ± 0.3%). Collectively, these findings support the hypothesis that OT within the hindbrain is effective at reducing food intake, weight gain, and adiposity and that NTS catecholamine neurons in addition to non-catecholaminergic neurons are downstream targets of CNS OT.
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Affiliation(s)
- Vishwanath T. Anekonda
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Benjamin W. Thompson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Jacqueline M. Ho
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA;
| | - Zachary S. Roberts
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Melise M. Edwards
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Ha K. Nguyen
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Andrew D. Dodson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Tami Wolden-Hanson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Daniel W. Chukri
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Adam J. Herbertson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - James L. Graham
- Department of Nutrition and Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA; (J.L.G.); (P.J.H.)
| | - Peter J. Havel
- Department of Nutrition and Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA; (J.L.G.); (P.J.H.)
| | - Tomasz A. Wietecha
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA;
- UW Medicine Diabetes Institute, University of Washington School of Medicine, Seattle, WA 98109, USA;
| | - Kevin D. O’Brien
- UW Medicine Diabetes Institute, University of Washington School of Medicine, Seattle, WA 98109, USA;
- Division of Cardiology, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - James E. Blevins
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA;
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15
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Oxytocin and Food Intake Control: Neural, Behavioral, and Signaling Mechanisms. Int J Mol Sci 2021; 22:ijms221910859. [PMID: 34639199 PMCID: PMC8509519 DOI: 10.3390/ijms221910859] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 09/29/2021] [Accepted: 10/03/2021] [Indexed: 11/16/2022] Open
Abstract
The neuropeptide oxytocin is produced in the paraventricular hypothalamic nucleus and the supraoptic nucleus of the hypothalamus. In addition to its extensively studied influence on social behavior and reproductive function, central oxytocin signaling potently reduces food intake in both humans and animal models and has potential therapeutic use for obesity treatment. In this review, we highlight rodent model research that illuminates various neural, behavioral, and signaling mechanisms through which oxytocin’s anorexigenic effects occur. The research supports a framework through which oxytocin reduces food intake via amplification of within-meal physiological satiation signals rather than by altering between-meal interoceptive hunger and satiety states. We also emphasize the distributed neural sites of action for oxytocin’s effects on food intake and review evidence supporting the notion that central oxytocin is communicated throughout the brain, at least in part, through humoral-like volume transmission. Finally, we highlight mechanisms through which oxytocin interacts with various energy balance-associated neuropeptide and endocrine systems (e.g., agouti-related peptide, melanin-concentrating hormone, leptin), as well as the behavioral mechanisms through which oxytocin inhibits food intake, including effects on nutrient-specific ingestion, meal size control, food reward-motivated responses, and competing motivations.
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16
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Edwards MM, Nguyen HK, Dodson AD, Herbertson AJ, Wietecha TA, Wolden-Hanson T, Graham JL, Honeycutt MK, Slattery JD, O’Brien KD, Havel PJ, Blevins JE. Effects of Combined Oxytocin and Beta-3 Receptor Agonist (CL 316243) Treatment on Body Weight and Adiposity in Male Diet-Induced Obese Rats. Front Physiol 2021; 12:725912. [PMID: 34566687 PMCID: PMC8457402 DOI: 10.3389/fphys.2021.725912] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 08/05/2021] [Indexed: 11/13/2022] Open
Abstract
Previous studies have indicated that oxytocin (OT) reduces body weight in diet-induced obese (DIO) rodents through reductions in energy intake and increases in energy expenditure. We recently demonstrated that hindbrain [fourth ventricular (4V)] administration of OT evokes weight loss and elevates interscapular brown adipose tissue temperature (T IBAT ) in DIO rats. What remains unclear is whether OT can be used as an adjunct with other drugs that directly target beta-3 receptors in IBAT to promote BAT thermogenesis and reduce body weight in DIO rats. We hypothesized that the combined treatment of OT and the beta-3 agonist, CL 316243, would produce an additive effect to decrease body weight and adiposity in DIO rats by reducing energy intake and increasing BAT thermogenesis. We assessed the effects of 4V infusions of OT (16 nmol/day) or vehicle (VEH) in combination with daily intraperitoneal injections of CL 316243 (0.5 mg/kg) or VEH on food intake, T IBAT , body weight and body composition. OT and CL 316243 alone reduced body weight by 7.8 ± 1.3% (P < 0.05) and 9.1 ± 2.1% (P < 0.05), respectively, but the combined treatment produced more pronounced weight loss (15.5 ± 1.2%; P < 0.05) than either treatment alone. These effects were associated with decreased adiposity, adipocyte size, energy intake and increased uncoupling protein 1 (UCP-1) content in epididymal white adipose tissue (EWAT) (P < 0.05). In addition, CL 316243 alone (P < 0.05) and in combination with OT (P < 0.05) elevated T IBAT and IBAT UCP-1 content and IBAT thermogenic gene expression. These findings are consistent with the hypothesis that the combined treatment of OT and the beta-3 agonist, CL 316243, produces an additive effect to decrease body weight. The findings from the current study suggest that the effects of the combined treatment on energy intake, fat mass, adipocyte size and browning of EWAT were not additive and appear to be driven, in part, by transient changes in energy intake in response to OT or CL 316243 alone as well as CL 316243-elicited reduction of fat mass and adipocyte size and induction of browning of EWAT.
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Affiliation(s)
- Melise M. Edwards
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - Ha K. Nguyen
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - Andrew D. Dodson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - Adam J. Herbertson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - Tomasz A. Wietecha
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
- UW Medicine Diabetes Institute, University of Washington School of Medicine, Seattle, WA, United States
| | - Tami Wolden-Hanson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - James L. Graham
- Department of Nutrition, University of California, Davis, Davis, CA, United States
| | - Mackenzie K. Honeycutt
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - Jared D. Slattery
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
| | - Kevin D. O’Brien
- UW Medicine Diabetes Institute, University of Washington School of Medicine, Seattle, WA, United States
- Division of Cardiology, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
| | - Peter J. Havel
- Department of Nutrition, University of California, Davis, Davis, CA, United States
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - James E. Blevins
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, United States
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
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17
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Jeong JK, Dow SA, Young CN. Sensory Circumventricular Organs, Neuroendocrine Control, and Metabolic Regulation. Metabolites 2021; 11:metabo11080494. [PMID: 34436435 PMCID: PMC8402088 DOI: 10.3390/metabo11080494] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 07/13/2021] [Accepted: 07/27/2021] [Indexed: 11/16/2022] Open
Abstract
The central nervous system is critical in metabolic regulation, and accumulating evidence points to a distributed network of brain regions involved in energy homeostasis. This is accomplished, in part, by integrating peripheral and central metabolic information and subsequently modulating neuroendocrine outputs through the paraventricular and supraoptic nucleus of the hypothalamus. However, these hypothalamic nuclei are generally protected by a blood-brain-barrier limiting their ability to directly sense circulating metabolic signals—pointing to possible involvement of upstream brain nuclei. In this regard, sensory circumventricular organs (CVOs), brain sites traditionally recognized in thirst/fluid and cardiovascular regulation, are emerging as potential sites through which circulating metabolic substances influence neuroendocrine control. The sensory CVOs, including the subfornical organ, organum vasculosum of the lamina terminalis, and area postrema, are located outside the blood-brain-barrier, possess cellular machinery to sense the metabolic interior milieu, and establish complex neural networks to hypothalamic neuroendocrine nuclei. Here, evidence for a potential role of sensory CVO-hypothalamic neuroendocrine networks in energy homeostasis is presented.
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Affiliation(s)
| | | | - Colin N. Young
- Correspondence: ; Tel.: +1-202-994-9575; Fax: +1-202-994-287
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18
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Kerem L, Lawson EA. The Effects of Oxytocin on Appetite Regulation, Food Intake and Metabolism in Humans. Int J Mol Sci 2021; 22:7737. [PMID: 34299356 PMCID: PMC8306733 DOI: 10.3390/ijms22147737] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 07/13/2021] [Accepted: 07/16/2021] [Indexed: 12/18/2022] Open
Abstract
The hypothalamic peptide oxytocin and its receptor are involved in a range of physiological processes, including parturition, lactation, cell growth, wound healing, and social behavior. More recently, increasing evidence has established the effects of oxytocin on food intake, energy expenditure, and peripheral metabolism. In this review, we provide a comprehensive description of the central oxytocinergic system in which oxytocin acts to shape eating behavior and metabolism. Next, we discuss the peripheral beneficial effects oxytocin exerts on key metabolic organs, including suppression of visceral adipose tissue inflammation, skeletal muscle regeneration, and bone tissue mineralization. A brief summary of oxytocin actions learned from animal models is presented, showing that weight loss induced by chronic oxytocin treatment is related not only to its anorexigenic effects, but also to the resulting increase in energy expenditure and lipolysis. Following an in-depth discussion on the technical challenges related to endogenous oxytocin measurements in humans, we synthesize data related to the association between endogenous oxytocin levels, weight status, metabolic syndrome, and bone health. We then review clinical trials showing that in humans, acute oxytocin administration reduces food intake, attenuates fMRI activation of food motivation brain areas, and increases activation of self-control brain regions. Further strengthening the role of oxytocin in appetite regulation, we review conditions of hypothalamic insult and certain genetic pathologies associated with oxytocin depletion that present with hyperphagia, extreme weight gain, and poor metabolic profile. Intranasal oxytocin is currently being evaluated in human clinical trials to learn whether oxytocin-based therapeutics can be used to treat obesity and its associated sequela. At the end of this review, we address the fundamental challenges that remain in translating this line of research to clinical care.
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Affiliation(s)
- Liya Kerem
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA;
- Division of Pediatric Endocrinology, Massachusetts General Hospital for Children, Boston, MA 02114, USA
| | - Elizabeth A. Lawson
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA;
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19
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Edwards MM, Nguyen HK, Herbertson AJ, Dodson AD, Wietecha T, Wolden-Hanson T, Graham JL, O'Brien KD, Havel PJ, Blevins JE. Chronic hindbrain administration of oxytocin elicits weight loss in male diet-induced obese mice. Am J Physiol Regul Integr Comp Physiol 2021; 320:R471-R487. [PMID: 33470901 PMCID: PMC8238148 DOI: 10.1152/ajpregu.00294.2020] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 01/15/2021] [Accepted: 01/16/2021] [Indexed: 02/08/2023]
Abstract
Previous studies indicate that oxytocin (OT) administration reduces body weight in high-fat diet (HFD)-induced obese (DIO) rodents through both reductions in food intake and increases in energy expenditure. We recently demonstrated that chronic hindbrain [fourth ventricular (4V)] infusions of OT evoke weight loss in DIO rats. Based on these findings, we hypothesized that chronic 4V OT would elicit weight loss in DIO mice. We assessed the effects of 4V infusions of OT (16 nmol/day) or vehicle over 28 days on body weight, food intake, and body composition. OT reduced body weight by approximately 4.5% ± 1.4% in DIO mice relative to OT pretreatment body weight (P < 0.05). These effects were associated with reduced adiposity and adipocyte size [inguinal white adipose tissue (IWAT)] (P < 0.05) and attributed, in part, to reduced energy intake (P < 0.05) at a dose that did not increase kaolin intake (P = NS). OT tended to increase uncoupling protein-1 expression in IWAT (0.05 < P < 0.1) suggesting that OT stimulates browning of WAT. To assess OT-elicited changes in brown adipose tissue (BAT) thermogenesis, we examined the effects of 4V OT on interscapular BAT temperature (TIBAT). 4V OT (1 µg) elevated TIBAT at 0.75 (P = 0.08), 1, and 1.25 h (P < 0.05) postinjection; a higher dose (5 µg) elevated TIBAT at 0.75-, 1-, 1.25-, 1.5-, 1.75- (P < 0.05), and 2-h (0.05 < P < 0.1) postinjection. Together, these findings support the hypothesis that chronic hindbrain OT treatment evokes sustained weight loss in DIO mice by reducing energy intake and increasing BAT thermogenesis at a dose that is not associated with evidence of visceral illness.
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MESH Headings
- Adipocytes, Brown/drug effects
- Adipocytes, Brown/metabolism
- Adipocytes, Brown/pathology
- Adipocytes, White/drug effects
- Adipocytes, White/metabolism
- Adipocytes, White/pathology
- Adiposity/drug effects
- Animals
- Anti-Obesity Agents/administration & dosage
- Diet, High-Fat
- Disease Models, Animal
- Eating/drug effects
- Energy Intake/drug effects
- Infusions, Intraventricular
- Leptin/blood
- Male
- Mice, Inbred C57BL
- Obesity/drug therapy
- Obesity/metabolism
- Obesity/pathology
- Obesity/physiopathology
- Oxytocin/administration & dosage
- Rhombencephalon/drug effects
- Rhombencephalon/physiopathology
- Thermogenesis/drug effects
- Uncoupling Protein 1/metabolism
- Weight Loss/drug effects
- Mice
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Affiliation(s)
- Melise M Edwards
- Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Veteran Affairs Puget Sound Health Care System, Seattle, Washington
| | - Ha K Nguyen
- Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Veteran Affairs Puget Sound Health Care System, Seattle, Washington
| | - Adam J Herbertson
- Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Veteran Affairs Puget Sound Health Care System, Seattle, Washington
| | - Andrew D Dodson
- Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Veteran Affairs Puget Sound Health Care System, Seattle, Washington
| | - Tomasz Wietecha
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, Washington
- UW Medicine Diabetes Institute, University of Washington School of Medicine, Seattle, Washington
| | - Tami Wolden-Hanson
- Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Veteran Affairs Puget Sound Health Care System, Seattle, Washington
| | - James L Graham
- Department of Nutrition, University of California, Davis, California
| | - Kevin D O'Brien
- UW Medicine Diabetes Institute, University of Washington School of Medicine, Seattle, Washington
- Division of Cardiology, Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Peter J Havel
- Department of Nutrition, University of California, Davis, California
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, California
| | - James E Blevins
- Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Veteran Affairs Puget Sound Health Care System, Seattle, Washington
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, Washington
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Abstract
The hypothalamic peptide oxytocin has been increasingly recognized as a hormone and neurotransmitter with important effects on energy intake, metabolism, and body weight and is under investigation as a potential novel therapeutic agent for obesity. The main neurons producing oxytocin and expressing the oxytocin receptor are strategically located in brain areas known to be critically involved in homeostatic energy balance as well as hedonic and motivational aspects of eating behavior. In this chapter, we will review the central and peripheral physiology of oxytocin and the interaction of oxytocin with key hormones and neural circuitries that affect food intake and metabolism. Next, we will synthesize the available data on endogenous oxytocin levels related to caloric intake, body weight, and metabolic status. We will then review the effects of exogenous oxytocin administration on eating behavior, body weight, and metabolism in humans, including in healthy individuals as well as specific populations with suspected perturbations involving oxytocin pathways. Finally, we will address the promise and fundamental challenges of translating this line of research to clinical care.
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Affiliation(s)
- Liya Kerem
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States; Division of Pediatric Endocrinology, Massachusetts General Hospital for Children, Boston, MA, United States
| | - Elizabeth A Lawson
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States.
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21
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Wald HS, Chandra A, Kalluri A, Ong ZY, Hayes MR, Grill HJ. NTS and VTA oxytocin reduces food motivation and food seeking. Am J Physiol Regul Integr Comp Physiol 2020; 319:R673-R683. [PMID: 33026822 DOI: 10.1152/ajpregu.00201.2020] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Oxytocin (OT) is a neuropeptide whose central receptor-mediated actions include reducing food intake. One mechanism of its behavioral action is the amplification of the feeding inhibitory effects of gastrointestinal (GI) satiation signals processed by hindbrain neurons. OT treatment also reduces carbohydrate intake in humans and rodents, and correspondingly, deficits in central OT receptor (OT-R) signaling increase sucrose self-administration. This suggests that additional processes contribute to central OT effects on feeding. This study investigated the hypothesis that central OT reduces food intake by decreasing food seeking and food motivation. As central OT-Rs are expressed widely, a related focus was to assess the role of one or more OT-R-expressing nuclei in food motivation and food-seeking behavior. OT was delivered to the lateral ventricle (LV), nucleus tractus solitarius (NTS), or ventral tegmental area (VTA), and a progressive ratio (PR) schedule of operant reinforcement and an operant reinstatement paradigm were used to measure motivated feeding behavior and food-seeking behavior, respectively. OT delivered to the LV, NTS, or VTA reduced 1) motivation to work for food and 2) reinstatement of food-seeking behavior. Results provide a novel and additional interpretation for central OT-driven food intake inhibition to include the reduction of food motivation and food seeking.
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Affiliation(s)
- Hallie S Wald
- Department of Psychology, Institute of Diabetes Obesity and Metabolism, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ananya Chandra
- Department of Psychology, Institute of Diabetes Obesity and Metabolism, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Anita Kalluri
- Department of Psychology, Institute of Diabetes Obesity and Metabolism, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Zhi Yi Ong
- School of Psychology, University of New South Wales, Sydney, Australia
| | - Matthew R Hayes
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Harvey J Grill
- Department of Psychology, Institute of Diabetes Obesity and Metabolism, University of Pennsylvania, Philadelphia, Pennsylvania
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22
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Yuan J, Zhang R, Wu R, Gu Y, Lu Y. The effects of oxytocin to rectify metabolic dysfunction in obese mice are associated with increased thermogenesis. Mol Cell Endocrinol 2020; 514:110903. [PMID: 32531419 DOI: 10.1016/j.mce.2020.110903] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 06/03/2020] [Accepted: 06/03/2020] [Indexed: 01/12/2023]
Abstract
Oxytocin, a protein hormone mainly produced by hypothalamus, has been shown to repress body weight gain in obese animals, in part, by reducing food intake and increasing energy expenditure. Till now, activation of brown fat tissue (BAT) thermogenesis and white adipose tissue (WAT) browning are considered as two main factors for oxytocin-induced energy expenditure. However, the underlying molecular mechanisms are still not understood well. Here, we observed that oxytocin expression in the hypothalamus and its receptor in adipose tissues were induced by cold exposure in mice. In differentiated adipocytes, oxytocin stimulated brown adipocyte specific gene expression by inducing PRDM16. In high fat diet induced obese mice, oxytocin delivery by osmotic minipumps increased body core temperature and decreased body weight gain. Glucose and insulin tolerance were improved by oxytocin. Hyperinsulinemia and fatty liver were ameliorated in oxytocin-treated animals. Moreover, oxytocin treatment induced thermogenic gene expressions in BAT, inguinal WAT (iWAT), and skeletal muscle. Taken together, our findings revealed a new aspect of oxytocin, i.e. oxytocin induces iWAT browning and stimulates thermogenesis in BAT, iWAT and skeletal muscle, through which oxytocin promotes thermogenesis and thus combats obesity and metabolic dysfunctions.
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Affiliation(s)
- Jin Yuan
- Department of Endocrinology, The Second Affiliated Hospital of Nanjing Medical University, 121 Jiangjiayuan Road, Nanjing, Jiangsu, 210011, China; Department of Endocrinology and Metabolism, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China, 20 Xisi Road, Nantong, Jiangsu, 226001, China
| | - Rongping Zhang
- Department of Endocrinology and Metabolism, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China, 20 Xisi Road, Nantong, Jiangsu, 226001, China
| | - Runze Wu
- Department of Endocrinology and Metabolism, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China, 20 Xisi Road, Nantong, Jiangsu, 226001, China
| | - Yunjuan Gu
- Department of Endocrinology and Metabolism, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China, 20 Xisi Road, Nantong, Jiangsu, 226001, China.
| | - Yibing Lu
- Department of Endocrinology, The Second Affiliated Hospital of Nanjing Medical University, 121 Jiangjiayuan Road, Nanjing, Jiangsu, 210011, China.
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23
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Paiva L, Leng G. Peripheral insulin administration enhances the electrical activity of oxytocin and vasopressin neurones in vivo. J Neuroendocrinol 2020; 32:e12841. [PMID: 32180284 DOI: 10.1111/jne.12841] [Citation(s) in RCA: 4] [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: 10/08/2019] [Revised: 02/25/2020] [Accepted: 02/25/2020] [Indexed: 11/30/2022]
Abstract
Oxytocin neurones are involved in the regulation of energy balance through diverse central and peripheral actions and, in rats, they are potently activated by gavage of sweet substances. Here, we test the hypothesis that this activation is mediated by the central actions of insulin. We show that, in urethane-anaesthetised rats, oxytocin cells in the supraoptic nucleus show prolonged activation after i.v. injections of insulin, and that this response is greater in fasted rats than in non-fasted rats. Vasopressin cells are also activated, although less consistently. We also show that this activation of oxytocin cells is independent of changes in plasma glucose concentration, and is completely blocked by central (i.c.v.) administration of an insulin receptor antagonist. Finally, we replicate the previously published finding that oxytocin cells are activated by gavage of sweetened condensed milk, and show that this response too is completely blocked by central administration of an insulin receptor antagonist. We conclude that the response of oxytocin cells to gavage of sweetened condensed milk is mediated by the central actions of insulin.
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Affiliation(s)
- Luis Paiva
- Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, UK
| | - Gareth Leng
- Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, UK
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24
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McCormack SE, Blevins JE, Lawson EA. Metabolic Effects of Oxytocin. Endocr Rev 2020; 41:5658523. [PMID: 31803919 PMCID: PMC7012298 DOI: 10.1210/endrev/bnz012] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 11/04/2019] [Indexed: 12/13/2022]
Abstract
There is growing evidence that oxytocin (OXT), a hypothalamic hormone well recognized for its effects in inducing parturition and lactation, has important metabolic effects in both sexes. The purpose of this review is to summarize the physiologic effects of OXT on metabolism and to explore its therapeutic potential for metabolic disorders. In model systems, OXT promotes weight loss by decreasing energy intake. Pair-feeding studies suggest that OXT-induced weight loss may also be partly due to increased energy expenditure and/or lipolysis. In humans, OXT appears to modulate both homeostatic and reward-driven food intake, although the observed response depends on nutrient milieu (eg, obese vs. nonobese), clinical characteristics (eg, sex), and experimental paradigm. In animal models, OXT is anabolic to muscle and bone, which is consistent with OXT-induced weight loss occurring primarily via fat loss. In some human observational studies, circulating OXT concentrations are also positively associated with lean mass and bone mineral density. The impact of exogenous OXT on human obesity is the focus of ongoing investigation. Future randomized, placebo-controlled clinical trials in humans should include rigorous, standardized, and detailed assessments of adherence, adverse effects, pharmacokinetics/pharmacodynamics, and efficacy in the diverse populations that may benefit from OXT, in particular those in whom hypothalamic OXT signaling may be abnormal or impaired (eg, individuals with Sim1 deficiency, Prader-Willi syndrome, or craniopharyngioma). Future studies will also have the opportunity to investigate the characteristics of new OXT mimetic peptides and the obligation to consider long-term effects, especially when OXT is given to children and adolescents. (Endocrine Reviews XX: XX - XX, 2020).
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Affiliation(s)
- Shana E McCormack
- Neuroendocrine Center, Division of Endocrinology and Diabetes, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - James E Blevins
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, Washington.,Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Elizabeth A Lawson
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts.,Department of Medicine, Harvard Medical School, Boston, Massachusetts
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25
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Lawson EA, Olszewski PK, Weller A, Blevins JE. The role of oxytocin in regulation of appetitive behaviour, body weight and glucose homeostasis. J Neuroendocrinol 2020; 32:e12805. [PMID: 31657509 PMCID: PMC7186135 DOI: 10.1111/jne.12805] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/14/2019] [Accepted: 10/24/2019] [Indexed: 12/28/2022]
Abstract
Obesity and its associated complications have reached epidemic proportions in the USA and also worldwide, highlighting the need for new and more effective treatments. Although the neuropeptide oxytocin (OXT) is well recognised for its peripheral effects on reproductive behaviour, the release of OXT from somatodendrites and axonal terminals within the central nervous system (CNS) is also implicated in the control of energy balance. In this review, we summarise historical data highlighting the effects of exogenous OXT as a short-term regulator of food intake in a context-specific manner and the receptor populations that may mediate these effects. We also describe what is known about the physiological role of endogenous OXT in the control of energy balance and whether serum and brain levels of OXT relate to obesity on a consistent basis across animal models and humans with obesity. We describe recent data on the effectiveness of chronic CNS administration of OXT to decrease food intake and weight gain or to elicit weight loss in diet-induced obese (DIO) and genetically obese mice and rats. Of clinical importance is the finding that chronic central and peripheral OXT treatments both evoke weight loss in obese animal models with impaired leptin signalling at doses that are not associated with visceral illness, tachyphylaxis or adverse cardiovascular effects. Moreover, these results have been largely recapitulated following chronic s.c. or intranasal treatment in DIO non-human primates (rhesus monkeys) and obese humans, respectively. We also identify plausible mechanisms that contribute to the effects of OXT on body weight and glucose homeostasis in rodents, non-human primates and humans. We conclude by describing the ongoing challenges that remain before OXT-based therapeutics can be used as a long-term strategy to treat obesity in humans.
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Affiliation(s)
- Elizabeth A Lawson
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Pawel K Olszewski
- Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
- Department of Integrative Biology and Physiology, Medical School, University of Minnesota, Minneapolis, MN, USA
| | - Aron Weller
- Psychology Department and Gonda Brain Research Center, Bar Ilan University, Ramat-Gan, Israel
| | - James E Blevins
- Department of Veterans Affairs Medical Center, Office of Research and Development Medical Research Service, VA Puget Sound Health Care System, Seattle, WA, USA
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA
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26
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Iwasa T, Matsuzaki T, Mayila Y, Kawakita T, Yanagihara R, Irahara M. The effects of chronic oxytocin administration on body weight and food intake in DHT-induced PCOS model rats. Gynecol Endocrinol 2020; 36:55-60. [PMID: 31220962 DOI: 10.1080/09513590.2019.1631276] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Polycystic ovary syndrome (PCOS) is commonly associated with metabolic disorders, which are exacerbated by obesity. Recent studies have revealed that oxytocin contributes to metabolic, appetite, and body weight regulation. In the present study, we evaluated the effects of chronic administration of oxytocin on body weight, food intake, and fat mass in a dihydrotestosterone-induced rat model of PCOS. Body weight, body weight change, and relative cumulative food intake were significantly lower in the oxytocin-treated PCOS rats than in the vehicle-treated control PCOS rats. Similarly, visceral adipocyte size was significantly smaller in the oxytocin-treated PCOS rats than in the vehicle-treated control PCOS rats. On the other hand, the numbers of cystic follicles in the ovary did not differ between the two groups. The chronic administration of oxytocin did not affect the rats' serum aspartate aminotransferase, alanine aminotransferase, or lactate dehydrogenase levels, indicating that it does not have adverse effects on hepatic function. These findings suggest that oxytocin could be a candidate drug for preventing the onset of obesity-related metabolic disorders in PCOS patients.
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Affiliation(s)
- Takeshi Iwasa
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Toshiya Matsuzaki
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Yiliyasi Mayila
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Takako Kawakita
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Rie Yanagihara
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Minoru Irahara
- Department of Obstetrics and Gynecology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
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27
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Pflimlin E, Zhou Z, Amso Z, Fu Q, Lee C, Muppiddi A, Joseph SB, Nguyen-Tran V, Shen W. Engineering a Potent, Long-Acting, and Periphery-Restricted Oxytocin Receptor Agonist with Anorexigenic and Body Weight Reducing Effects. J Med Chem 2019; 63:382-390. [PMID: 31850759 DOI: 10.1021/acs.jmedchem.9b01862] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The effects of oxytocin on food intake and body weight reduction have been demonstrated in both animal models and human clinical studies. Despite being efficacious, oxytocin is enzymatically unstable and thus considered to be unsuitable for long-term use in patients with obesity. Herein, a series of oxytocin derivatives were engineered through conjugation with fatty acid moieties that are known to exhibit high binding affinities to serum albumin. One analog (OT-12) in particular was shown to be a potent full agonist at the oxytocin receptor (OTR) in vitro with good selectivity and long half-life (24 h) in mice. Furthermore, OT-12 is peripherally restricted, with very limited brain exposure (1/190 of the plasma level). In a diet-induced obesity mouse model, daily subcutaneous administration of OT-12 exhibited more potent anorexigenic and body weight reducing effects than carbetocin. Thus, our results suggest that the long-acting, peripherally restricted OTR agonist may offer potential therapeutic benefits for obesity.
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Affiliation(s)
- Elsa Pflimlin
- Calibr at The Scripps Research Institute , La Jolla , California 92037 , United States
| | - Zhihong Zhou
- Calibr at The Scripps Research Institute , La Jolla , California 92037 , United States
| | - Zaid Amso
- Calibr at The Scripps Research Institute , La Jolla , California 92037 , United States
| | - Qiangwei Fu
- Calibr at The Scripps Research Institute , La Jolla , California 92037 , United States
| | - Candy Lee
- Calibr at The Scripps Research Institute , La Jolla , California 92037 , United States
| | - Avinash Muppiddi
- Calibr at The Scripps Research Institute , La Jolla , California 92037 , United States
| | - Sean B Joseph
- Calibr at The Scripps Research Institute , La Jolla , California 92037 , United States
| | - Vân Nguyen-Tran
- Calibr at The Scripps Research Institute , La Jolla , California 92037 , United States
| | - Weijun Shen
- Calibr at The Scripps Research Institute , La Jolla , California 92037 , United States
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28
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Kerem L, Hadjikhani N, Holsen L, Lawson EA, Plessow F. Oxytocin reduces the functional connectivity between brain regions involved in eating behavior in men with overweight and obesity. Int J Obes (Lond) 2019; 44:980-989. [PMID: 31740723 PMCID: PMC7192759 DOI: 10.1038/s41366-019-0489-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 10/11/2019] [Accepted: 10/31/2019] [Indexed: 02/06/2023]
Abstract
Background: Oxytocin (OXT), shown to decrease food intake in animal models and men, is a promising novel treatment for obesity. We have shown that in men with overweight and obesity, intranasal (IN) OXT reduced the functional magnetic resonance imaging (fMRI) blood oxygenation level-dependent signal in the ventral tegmental area (VTA), the origin of the mesolimbic dopaminergic reward system, in response to high-calorie food vs. non-food images. Here, we employed functional connectivity fMRI analysis, which measures the synchrony in activation between neural systems in a context-dependent manner. We hypothesized that OXT would attenuate the functional connectivity of the VTA with key food motivation brain areas only when participants viewed high-calorie food stimuli. Methods: This randomized, double-blind, placebo-controlled crossover study of 24 IU IN OXT included 10 men with overweight or obesity (mean±SEM BMI: 28.9±0.8 kg/m2). Following drug administration, subjects completed an fMRI food motivation paradigm including images of high and low-calorie foods, non-food objects, and fixation stimuli. A psychophysiological interaction analysis was performed with the VTA as seed region. Results: Following OXT administration, compared with placebo, participants exhibited significantly attenuated functional connectivity between the VTA and the insula, oral somatosensory cortex, amygdala, hippocampus, operculum, and middle temporal gyrus in response to viewing high-calorie foods (Z≥3.1, cluster-corrected, p<0.05). There was no difference in functional connectivity between VTA and these brain areas when comparing OXT and placebo for low-calorie food, non-food, and fixation images. Conclusion: In men with overweight and obesity, OXT attenuates the functional connectivity between the VTA and food motivation brain regions in response to high-calorie visual food images. These findings could partially explain the observed anorexigenic effect of OXT, providing insight into the mechanism through which OXT ameliorates food cue-induced reward anticipation in patients with obesity. Additional studies are ongoing to further delineate the anorexigenic effect of OXT in obesity.
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Affiliation(s)
- Liya Kerem
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.,Division of Pediatric Endocrinology, Massachusetts General Hospital for Children, Boston, MA, USA
| | - Nouchine Hadjikhani
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Boston, MA, USA.,Gillberg Neuropsychiatry Center, University of Gothenburg, Gothenburg, Sweden
| | - Laura Holsen
- Division of Women's Health, Department of Medicine and Department of Psychiatry, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Elizabeth A Lawson
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
| | - Franziska Plessow
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
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Weingarten MFJ, Scholz M, Wohland T, Horn K, Stumvoll M, Kovacs P, Tönjes A. Circulating Oxytocin Is Genetically Determined and Associated With Obesity and Impaired Glucose Tolerance. J Clin Endocrinol Metab 2019; 104:5621-5632. [PMID: 31361301 DOI: 10.1210/jc.2019-00643] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Accepted: 07/22/2019] [Indexed: 01/01/2023]
Abstract
CONTEXT Despite the emerging evidence on the role of oxytocin (OXT) in metabolic diseases, there is a lack of well-powered studies addressing the relationship of circulating OXT with obesity and diabetes. OBJECTIVES AND DESIGN Here, we measured OXT in a study cohort (n = 721; 396 women, 325 men; mean age ± SD, 47.7 ± 15.2 years) with subphenotypes related to obesity, including anthropometric traits such as body mass index [BMI (mean ± SD), 26.8 ± 4.6 kg/m2], waist-to-hip ratio (WHR; 0.88 ± 0.09), blood parameters (glucose, 5.32 ± 0.50 mmol/L; insulin, 5.3 ± 3.3 µU/mL), and oral glucose tolerance test to clarify the association with OXT. We also tested in a genome-wide association study (GWAS) whether the interindividual variation in OXT serum levels might be explained by genetic variation. RESULTS The OXT concentration was increased in subjects with elevated BMI and positively correlated with WHR, waist circumference, and triglyceride levels. The OXT concentration in subjects with BMI <25 kg/m2 was significantly lower (n = 256; 78.6 pg/mL) than in subjects with a BMI between 25 and 30 kg/m2 (n = 314; 98.5 pg/mL, P = 6 × 10-6) and with BMI >30 kg/m2 (n = 137; 106.4 pg/mL, P = 8 × 10-6). OXT levels were also positively correlated with plasma glucose and insulin and were elevated in subjects with impaired glucose tolerance (P = 4.6 × 10-3). Heritability of OXT was estimated at 12.8%. In a GWAS, two hits in linkage disequilibrium close (19 kb) to the OXT reached genome-wide significant association (top-hit rs12625893, P = 3.1 × 10-8, explained variance 3%). CONCLUSIONS Our data show that OXT is genetically affected by a variant near OXT and is associated with obesity and impaired glucose tolerance.
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Affiliation(s)
| | - Markus Scholz
- Institute for Medical Informatics, Statistics, and Epidemiology, University of Leipzig, Leipzig, Germany
- LIFE Research Center, University of Leipzig, Leipzig, Germany
| | - Tobias Wohland
- IFB Adiposity Diseases, University of Leipzig Medical Center, Leipzig, Germany
| | - Katrin Horn
- Institute for Medical Informatics, Statistics, and Epidemiology, University of Leipzig, Leipzig, Germany
- LIFE Research Center, University of Leipzig, Leipzig, Germany
| | - Michael Stumvoll
- Medical Department III-Endocrinology, Nephrology, Rheumatology, University of Leipzig Medical Center, Leipzig, Germany
| | - Peter Kovacs
- Medical Department III-Endocrinology, Nephrology, Rheumatology, University of Leipzig Medical Center, Leipzig, Germany
- IFB Adiposity Diseases, University of Leipzig Medical Center, Leipzig, Germany
| | - Anke Tönjes
- Medical Department III-Endocrinology, Nephrology, Rheumatology, University of Leipzig Medical Center, Leipzig, Germany
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Horta M, Kaylor K, Feifel D, Ebner NC. Chronic oxytocin administration as a tool for investigation and treatment: A cross-disciplinary systematic review. Neurosci Biobehav Rev 2019; 108:1-23. [PMID: 31647964 DOI: 10.1016/j.neubiorev.2019.10.012] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 09/10/2019] [Accepted: 10/18/2019] [Indexed: 12/18/2022]
Abstract
Oxytocin (OT) subserves various physiological, behavioral, and cognitive processes. This paired with the ability to administer OT with minimal and inconsistent side effects has spurred research to explore its therapeutic potential. Findings from single-dose studies indicate that OT administration may be beneficial, at least under certain circumstances. The state of the field, however, is less clear regarding effects from chronic OT administration, which more closely resembles long-term treatment. To address this gap, this review synthesizes existing findings on the use of chronic OT administration in animal and human work. In addition to detailing the effects of chronic OT administration across different functional domains, this review highlights factors that have contributed to mixed findings. Based on this review, a basic framework of interrelated regulatory functions sensitive to chronic OT administration is offered. The paper also identifies future research directions across different contexts, populations, and outcomes, specifically calling for more systematic and standardized research on chronic OT administration in humans to supplement and expand what is currently known from preclinical work.
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Affiliation(s)
- Marilyn Horta
- Department of Psychology, University of Florida, Gainesville, FL, USA.
| | - Kathryn Kaylor
- Department of Psychology, University of Florida, Gainesville, FL, USA
| | - David Feifel
- Department of Psychiatry, University of California, San Diego, CA, USA
| | - Natalie C Ebner
- Department of Psychology, University of Florida, Gainesville, FL, USA; Institute on Aging, Department of Aging & Geriatric Research, University of Florida, Gainesville, FL, USA
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Skinner JA, Garg ML, Dayas CV, Burrows TL. Is weight status associated with peripheral levels of oxytocin? A pilot study in healthy women. Physiol Behav 2019; 212:112684. [PMID: 31629767 DOI: 10.1016/j.physbeh.2019.112684] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 09/09/2019] [Accepted: 09/16/2019] [Indexed: 12/13/2022]
Abstract
The neuropeptide oxytocin is best known for its role during parturition and the milk-let down reflex. Recent evidence identifies a role for oxytocin in eating behaviour. After oxytocin administration, caloric intake is reduced with stronger inhibitory effects in individuals with obesity. Whether the experience of visual food cues affects secretion or circulating levels of oxytocin is unknown. This pilot study had three aims: 1) to measure fasting appetite hormones with a focus on plasma oxytocin concentrations; 2) determine whether healthy vs. hyperpalatable visual food cues differentially altered plasma oxytocin; and 3) assess whether appetite hormone responses to healthy vs. hyperpalatable food images depended on weight or food addiction status. Eighteen healthy women of varying weight status, with/without self-reported food addiction were recruited. Study participants completed a set of standardised questionnaires, including Yale Food Addiction Scale, and attended a one-off experimental session. Blood was collected before and after viewing two sets of food images (healthy and hyperpalatable foods). Participants were randomly allocated in a crossover design to view either healthy images or hyperpalatable foods first. A positive correlation between BMI and plasma oxytocin was found (r2 = 0.32, p = 0.021) at baseline. Oxytocin levels were higher, and cholecystokinin levels lower, in food addicted (n = 6) vs. non-food addicted females (p = 0.015 and p<0.001, respectively). There were no significant changes (p>0.05) in plasma oxytocin levels in response to either healthy or hyperpalatable food images. Given that endogenous oxytocin administration tends to suppress eating behaviour; these data indicate that oxytocin receptor desensitization or oxytocin resistance may be important factors in the pathogenesis of obesity and food addiction. However, further studies in larger samples are needed to determine if peripheral oxytocin is responsive to visual food cues.
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Affiliation(s)
- Janelle A Skinner
- Nutrition and Dietetics, School of Health Sciences, Faculty of Health and Medicine, University of Newcastle, Callaghan NSW 2308, Australia; Priority Research Centre for Physical Activity and Nutrition, University of Newcastle, Callaghan NSW 2308, Australia
| | - Manohar L Garg
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, Callaghan NSW 2308, Australia
| | - Christopher V Dayas
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, Callaghan NSW 2308, Australia
| | - Tracy L Burrows
- Nutrition and Dietetics, School of Health Sciences, Faculty of Health and Medicine, University of Newcastle, Callaghan NSW 2308, Australia; Priority Research Centre for Physical Activity and Nutrition, University of Newcastle, Callaghan NSW 2308, Australia.
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32
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Aulinas A, Plessow F, Pulumo RL, Asanza E, Mancuso CJ, Slattery M, Tolley C, Thomas JJ, Eddy KT, Miller KK, Klibanski A, Misra M, Lawson EA. Disrupted Oxytocin-Appetite Signaling in Females With Anorexia Nervosa. J Clin Endocrinol Metab 2019; 104:4931-4940. [PMID: 31251345 PMCID: PMC6734487 DOI: 10.1210/jc.2019-00926] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 06/24/2019] [Indexed: 02/06/2023]
Abstract
CONTEXT In healthy females, oxytocin levels decrease postmeal, corresponding to increased satiety. The postprandial response of oxytocin in females with anorexia nervosa (AN)/atypical AN is unknown. OBJECTIVES To determine the pattern of postprandial serum oxytocin levels in females with AN/atypical AN, relationship with appetite, and effect of weight, eating behavior, and endogenous estrogen status. DESIGN Cross-sectional. SETTING Clinical research center. PARTICIPANTS 67 women (36 with AN [<85% expected body weight (EBW)]; 31 with atypical AN [≥ 85% EBW)]), age 22.4 ± 0.9 (mean ± SEM) years, categorized by weight, restricting vs binge/purge behavior, and estrogen status. INTERVENTIONS Standardized mixed meal. MAIN OUTCOME MEASUREMENTS Blood sampling for oxytocin occurred fasting and 30, 60, and 120 minutes postmeal. Subjective appetite was assessed using visual analog scales. RESULTS In females with AN/atypical AN, oxytocin levels decreased from fasting to 60 (P = 0.002) and 120 (P = 0.005) minutes postmeal. The decrease in oxytocin from fasting to 120 minutes was greater in females with atypical AN than AN (P = 0.027) and did not differ by restricting vs binge/purge behavior or estrogen status. Controlling for caloric intake, the decrease in oxytocin was inversely related to the decrease in hunger postmeal in females with atypical AN (P = 0.04). CONCLUSIONS In females with AN/atypical AN, oxytocin levels decrease postmeal, as established in healthy females. Weight, but not restricting vs binge/purging nor endogenous estrogen status, affects postprandial oxytocin levels. The postprandial change in serum oxytocin levels is related to appetite in females with atypical AN only, suggesting a disconnect between oxytocin secretion and appetite in the undernourished state.
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Affiliation(s)
- Anna Aulinas
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | - Franziska Plessow
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | | | - Elisa Asanza
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
| | | | - Meghan Slattery
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
| | - Christiane Tolley
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
| | - Jennifer J Thomas
- Harvard Medical School, Boston, Massachusetts
- Eating Disorders Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts
| | - Kamryn T Eddy
- Harvard Medical School, Boston, Massachusetts
- Eating Disorders Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts
| | - Karen K Miller
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | - Anne Klibanski
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | - Madhusmita Misra
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
- Division of Pediatric Endocrinology, Massachusetts General Hospital for Children, Boston, Massachusetts
| | - Elizabeth A Lawson
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
- Correspondence and Reprint Requests: Elizabeth A. Lawson, Neuroendocrine Unit, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachussetts 02114. E-mail:
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Abstract
PURPOSE OF REVIEW The neurohypophysial endocrine system is identified here as a potential target for therapeutic interventions toward improving obesity-related metabolic dysfunction, given its coinciding pleiotropic effects on psychological, neurological and metabolic systems that are disrupted in obesity. RECENT FINDINGS Copeptin, the C-terminal portion of the precursor of arginine-vasopressin, is positively associated with body mass index and risk of type 2 diabetes. Plasma oxytocin is decreased in obesity and several other conditions of abnormal glucose homeostasis. Recent data also show non-classical tissues, such as myocytes, hepatocytes and β-cells, exhibit responses to oxytocin and vasopressin receptor binding that may contribute to alterations in metabolic function. The modulation of anorexigenic and orexigenic pathways appears to be the dominant mechanism underlying the effects of oxytocin and vasopressin on body weight regulation; however, there are apparent limitations associated with their use in direct pharmacological applications. A clearer picture of their wider physiological effects is needed before either system can be considered for therapeutic use.
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Affiliation(s)
| | - Faidon Magkos
- Department of Nutrition, Exercise and Sports-Section of Obesity Research, Faculty of Science, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg C; Building 2-85, Room H134, Copenhagen, Denmark.
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Snider B, Geiser A, Yu XP, Beebe EC, Willency JA, Qing K, Guo L, Lu J, Wang X, Yang Q, Efanov A, Adams AC, Coskun T, Emmerson PJ, Alsina-Fernandez J, Ai M. Long-Acting and Selective Oxytocin Peptide Analogs Show Antidiabetic and Antiobesity Effects in Male Mice. J Endocr Soc 2019; 3:1423-1444. [PMID: 31286109 PMCID: PMC6608564 DOI: 10.1210/js.2019-00004] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 05/10/2019] [Indexed: 12/29/2022] Open
Abstract
Oxytocin (OXT) has been shown to suppress appetite, induce weight loss, and improve glycemic control and lipid metabolism in several species, including humans, monkeys, and rodents. However, OXT's short half-life in circulation and lack of receptor selectivity limit its application and efficacy. In this study, we report an OXT peptide analog (OXTGly) that is potent and selective for the OXT receptor (OXTR). OXT, but not OXTGly, activated vasopressin receptors in vitro and acutely increased blood pressure in vivo when administered IP. OXT suppressed food intake in mice, whereas OXTGly had a moderate effect on food intake when administered IP or intracerebroventricularly. Both OXT (IP) and OXTGly (IP) improved glycemic control in glucose tolerance tests. Additionally, both OXT (IP) and OXTGly (IP) stimulated insulin, glucagon-like peptide 1, and glucagon secretion in mice. We generated lipid-conjugated OXT (acylated-OXT) and OXTGly (acylated-OXTGly) and demonstrated that these molecules have significantly extended half-lives in vivo. Compared with OXT, 2-week treatment of diet-induced obese mice with acylated-OXT [subcutaneous(ly) (SC)] resulted in enhanced body weight reduction, an improved lipid profile, and gene expression changes consistent with increased lipolysis and decreased gluconeogenesis. Treatment with acylated-OXTGly (SC) also resulted in a statistically significant weight loss, albeit to a lesser degree compared with acylated-OXT treatment. In conclusion, we demonstrate that selective activation of the OXTR pathway results in both acute and chronic metabolic benefits, whereas potential activation of vasopressin receptors by nonselective OXT analogs causes physiological stress that contributes to additional weight loss.
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Affiliation(s)
- Brandy Snider
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Andrea Geiser
- Biotechnology Peptide Group, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Xiao-peng Yu
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Emily Cathleen Beebe
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Jill Amanda Willency
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Keyun Qing
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Lili Guo
- Biotechnology Peptide Group, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Jianliang Lu
- Medicinal Chemistry, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Xiaojun Wang
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Qian Yang
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Alexander Efanov
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Andrew Charles Adams
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Tamer Coskun
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Paul Joseph Emmerson
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Jorge Alsina-Fernandez
- Biotechnology Peptide Group, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
| | - Minrong Ai
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana
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Aulinas A, Pulumo RL, Asanza E, Mancuso CJ, Slattery M, Tolley C, Plessow F, Thomas JJ, Eddy KT, Miller KK, Klibanski A, Misra M, Lawson EA. Endogenous Oxytocin Levels in Relation to Food Intake, Menstrual Phase, and Age in Females. J Clin Endocrinol Metab 2019; 104:1348-1356. [PMID: 30445502 PMCID: PMC6408871 DOI: 10.1210/jc.2018-02036] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 11/13/2018] [Indexed: 12/22/2022]
Abstract
CONTEXT Oxytocin regulates a range of physiological processes including eating behavior and oxytocin administration reduces caloric intake in males. There are few data on oxytocin and eating behavior in healthy females or on the response of endogenous oxytocin to food intake and its relationship to appetite in humans. OBJECTIVES To determine the postprandial pattern of oxytocin levels, the relationship between oxytocin and appetite, and the impact of menstrual cycle phase and age on oxytocin levels in females. DESIGN Cross-sectional. SETTING Clinical research center. PARTICIPANTS Fifty-five healthy females (age 10 to 45 years). INTERVENTIONS A standardized mixed meal was administered. MAIN OUTCOME MEASUREMENTS Blood sampling for oxytocin occurred at fasting and at 30, 60, and 120 minutes postmeal. Appetite was assessed using Visual Analogue Scales pre- and postmeal. RESULTS Mean fasting oxytocin levels were 1011.2 ± 52.3 pg/mL (SEM) and decreased at 30 and 60 minutes postmeal (P = 0.001 and P = 0.003, respectively). Mean oxytocin levels decreased19.6% ± 3.0% from baseline to nadir. Oxytocin area under the curve was lower in the early to midfollicular menstrual cycle phase (P = 0.0003) and higher in younger females (P = 0.002). The percent change in oxytocin (baseline to nadir) was associated with postprandial hunger (rs = -0.291, P = 0.03) and fullness (rs = 0.345, P = 0.009). These relations remained significant after controlling for calories consumed, menstrual cycle status, and age (P = 0.023 and P = 0.0001, respectively). CONCLUSIONS Peripheral oxytocin levels in females decrease after a mixed meal and are associated with appetite independent of menstrual phase, age, and caloric intake, suggesting that endogenous oxytocin levels may play a role in perceived hunger and satiety.
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Affiliation(s)
- Anna Aulinas
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston Massachusetts
| | | | - Elisa Asanza
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
| | | | - Meghan Slattery
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
| | - Christiane Tolley
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
| | - Franziska Plessow
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston Massachusetts
| | - Jennifer J Thomas
- Harvard Medical School, Boston Massachusetts
- Eating Disorders Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, Boston Massachusetts
| | - Kamryn T Eddy
- Harvard Medical School, Boston Massachusetts
- Eating Disorders Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, Boston Massachusetts
| | - Karen K Miller
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston Massachusetts
| | - Anne Klibanski
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston Massachusetts
| | - Madhusmita Misra
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston Massachusetts
- Pediatric Endocrine Unit, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts
| | - Elizabeth A Lawson
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts
- Harvard Medical School, Boston Massachusetts
- Correspondence and Reprint Requests: Elizabeth A. Lawson, MD, MMSc, Neuroendocrine Unit, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachusetts 02114. E-mail:
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Onaka T, Takayanagi Y. Role of oxytocin in the control of stress and food intake. J Neuroendocrinol 2019; 31:e12700. [PMID: 30786104 PMCID: PMC7217012 DOI: 10.1111/jne.12700] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 02/12/2019] [Accepted: 02/15/2019] [Indexed: 12/20/2022]
Abstract
Oxytocin neurones in the hypothalamus are activated by stressful stimuli and food intake. The oxytocin receptor is located in various brain regions, including the sensory information-processing cerebral cortex; the cognitive information-processing prefrontal cortex; reward-related regions such as the ventral tegmental areas, nucleus accumbens and raphe nucleus; stress-related areas such as the amygdala, hippocampus, ventrolateral part of the ventromedial hypothalamus and ventrolateral periaqueductal gray; homeostasis-controlling hypothalamus; and the dorsal motor complex controlling intestinal functions. Oxytocin affects behavioural and neuroendocrine stress responses and terminates food intake by acting on the metabolic or nutritional homeostasis system, modulating emotional processing, reducing reward values of food intake, and facilitating sensory and cognitive processing via multiple brain regions. Oxytocin also plays a role in interactive actions between stress and food intake and contributes to adaptive active coping behaviours.
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Affiliation(s)
- Tatsushi Onaka
- Division of Brain and NeurophysiologyDepartment of PhysiologyJichi Medical UniversityShimotsuke‐shiJapan
| | - Yuki Takayanagi
- Division of Brain and NeurophysiologyDepartment of PhysiologyJichi Medical UniversityShimotsuke‐shiJapan
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Head MA, Jewett DC, Gartner SN, Klockars A, Levine AS, Olszewski PK. Effect of Oxytocin on Hunger Discrimination. Front Endocrinol (Lausanne) 2019; 10:297. [PMID: 31156549 PMCID: PMC6529581 DOI: 10.3389/fendo.2019.00297] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 04/25/2019] [Indexed: 12/28/2022] Open
Abstract
Centrally and peripherally administered oxytocin (OT) decreases food intake and activation of the endogenous OT systems, which is associated with termination of feeding. Evidence gathered thus far points to OT as a facilitator of early satiation, a peptide that reduces the need for a meal that has already begun. It is not known, however, whether OT can diminish a feeling of hunger, thereby decreasing a perceived need to seek calories. Therefore, in the current project, we first confirmed that intraperitoneal (i.p.) OT at 0.3-1 mg/kg reduces food intake in deprived and non-deprived rats. We then used those OT doses in a unique hunger discrimination protocol. First, rats were trained to discriminate between 22- and 2-h food deprivation (hungry vs. sated state) in a two-lever operant procedure. After rats acquired the discrimination, they were food-restricted for 22 h and given i.p. OT before a generalization test session. OT did not decrease 22-h deprivation-appropriate responding to match that following 2-h food deprivation, thus, it did not reduce the perceived level of hunger. In order to better understand the mechanisms behind this ineffectiveness of OT, we used c-Fos immunohistochemistry to determine whether i.p. OT activates a different subset of feeding-related brain sites under 22- vs. 2-h deprivation. We found that in sated animals, OT induces c-Fos changes in a broader network of hypothalamic and brain stem sites compared to those affected in the hungry state. Finally, by employing qPCR analysis, we asked whether food deprivation vs. sated state have an impact on OT receptor expression in the brain stem, a CNS "entry" region for peripheral OT. Fasted animals had significantly lower OT receptor mRNA levels than their ad libitum-fed counterparts. We conclude that OT does not diminish a feeling of hunger before a start of a meal. Instead OT's anorexigenic properties are manifested once consumption has already begun which is-at least to some extent-driven by changes in brain responsiveness to OT treatment in the hungry vs. fed state. OT should be viewed as a mediator of early satiation rather than as a molecule that diminishes perceived hunger.
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Affiliation(s)
- Mitchell A. Head
- Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | - David C. Jewett
- Department of Psychology, University of Wisconsin-Eau Claire, Eau Claire, WI, United States
| | - Sarah N. Gartner
- Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | - Anica Klockars
- Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | - Allen S. Levine
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN, United States
| | - Pawel K. Olszewski
- Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN, United States
- *Correspondence: Pawel K. Olszewski
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38
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Ding C, Leow MKS, Magkos F. Oxytocin in metabolic homeostasis: implications for obesity and diabetes management. Obes Rev 2019; 20:22-40. [PMID: 30253045 PMCID: PMC7888317 DOI: 10.1111/obr.12757] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 07/25/2018] [Accepted: 07/25/2018] [Indexed: 12/20/2022]
Abstract
Oxytocin was once understood solely as a neuropeptide with a central role in social bonding, reproduction, parturition, lactation and appetite regulation. Recent evidence indicates that oxytocin enhances glucose uptake and lipid utilization in adipose tissue and skeletal muscle, suggesting that dysfunction of the oxytocin system could underlie the pathogenesis of insulin resistance and dyslipidaemia. Murine studies revealed that deficiencies in oxytocin signalling and oxytocin receptor expression lead to obesity despite normal food intake, motor activity and increased leptin levels. In addition, plasma oxytocin concentration is notably lower in obese individuals with diabetes, which may suggest an involvement of the oxytocin system in the pathogenesis of cardiometabolic disease. More recently, small scale studies demonstrated that intranasal administration of oxytocin was associated with significant weight loss as well as improvements in insulin sensitivity and pancreatic β-cell responsivity in human subjects. The multi-pronged effects of oxytocin signalling on improving peripheral insulin sensitivity, pancreatic function and lipid homeostasis strongly suggest a role for this system as a therapeutic target in obesity and diabetes management. The complexity of obesity aetiology and the pathogenesis of obesity-related metabolic complications underscore the need for a systems approach to better understand the role of oxytocin in metabolic function.
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Affiliation(s)
- C Ding
- Clinical Nutrition Research Centre (CNRC), Singapore Institute for Clinical Sciences (SICS), Agency for Science, Technology and Research (A*STAR) and National University Health System, Singapore
| | - M K-S Leow
- Clinical Nutrition Research Centre (CNRC), Singapore Institute for Clinical Sciences (SICS), Agency for Science, Technology and Research (A*STAR) and National University Health System, Singapore.,Department of Endocrinology, Tan Tock Seng Hospital, Singapore.,Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - F Magkos
- Clinical Nutrition Research Centre (CNRC), Singapore Institute for Clinical Sciences (SICS), Agency for Science, Technology and Research (A*STAR) and National University Health System, Singapore.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore
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Skinner JA, Campbell EJ, Dayas CV, Garg ML, Burrows TL. The relationship between oxytocin, dietary intake and feeding: A systematic review and meta-analysis of studies in mice and rats. Front Neuroendocrinol 2019; 52:65-78. [PMID: 30315826 DOI: 10.1016/j.yfrne.2018.09.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 09/13/2018] [Accepted: 09/28/2018] [Indexed: 01/11/2023]
Abstract
The neuropeptide oxytocin has been associated with food intake and feeding behaviour. This systematic review aimed to investigate the impact of oxytocin on dietary intake and feeding behaviour in rodent studies. Six electronic databases were searched to identify published studies to April 2018. Preclinical studies in mice and rats were included if they reported: (1) a dietary measure (i.e. food or nutrient and/or behaviour (2) an oxytocin measure, and (3) relationship between the two measures. A total of 75 articles (n = 246 experiments) were included, and study quality appraised. The majority of studies were carried out in males (87%). The top three oxytocin outcomes assessed were: exogenous oxytocin administration (n = 126), oxytocin-receptor antagonist administration (n = 46) and oxytocin gene deletion (n = 29). Meta-analysis of exogenous studies in mice (3 studies, n = 43 comparisons) and rats (n = 8 studies, n = 82 comparisons) showed an overall decrease in food intake with maximum effect shown at 2 h post-administration.
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Affiliation(s)
- Janelle A Skinner
- Nutrition and Dietetics, School of Health Sciences, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW 2308, Australia; Priority Research Centre for Physical Activity and Nutrition, University of Newcastle, Callaghan, NSW 2308, Australia.
| | - Erin J Campbell
- The Florey Institute of Neuroscience and Mental Health, Parkville, Victoria 3052, Australia; Florey Department of Neuroscience and Mental Health, University of Melbourne, Victoria 3010, Australia.
| | - Christopher V Dayas
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW 2308, Australia.
| | - Manohar L Garg
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW 2308, Australia.
| | - Tracy L Burrows
- Nutrition and Dietetics, School of Health Sciences, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW 2308, Australia; Priority Research Centre for Physical Activity and Nutrition, University of Newcastle, Callaghan, NSW 2308, Australia.
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Labyb M, Chrétien C, Caillon A, Rohner-Jeanrenaud F, Altirriba J. Oxytocin Administration Alleviates Acute but Not Chronic Leptin Resistance of Diet-Induced Obese Mice. Int J Mol Sci 2018; 20:ijms20010088. [PMID: 30587816 PMCID: PMC6337181 DOI: 10.3390/ijms20010088] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 12/07/2018] [Accepted: 12/12/2018] [Indexed: 12/19/2022] Open
Abstract
Whereas leptin administration only has a negligible effect on the treatment of obesity, it has been demonstrated that its action can be improved by co-administration of leptin and one of its sensitizers. Considering that oxytocin treatment decreases body weight in obese animals and humans, we investigated the effects of oxytocin and leptin cotreatment. First, lean and diet-induced obese (DIO) mice were treated with oxytocin for 2 weeks and we measured the acute leptin response. Second, DIO mice were treated for 2 weeks with saline, oxytocin (50 μg/day), leptin (20 or 40 µg/day) or oxytocin plus leptin. Oxytocin pre-treatment restored a normal acute leptin response, decreasing food intake and body weight gain. Chronic continuous administration of oxytocin or leptin at 40 µg/day decreased body weight in the presence (leptin) or in the absence (oxytocin) of cumulative differences in food intake. Saline or leptin treatment at 20 µg/day had no impact on body weight. Oxytocin and leptin cotreatments had no additional effects compared with single treatments. These results point to the fact that chronic oxytocin treatment improves the acute, but not the chronic leptin response, suggesting that this treatment could be used to improve the short-term satiety effect of leptin.
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Affiliation(s)
- Mehdi Labyb
- Laboratory of Metabolism, Department of Medicine Specialties, Faculty of Medicine, University of Geneva, CH1211 Geneva, Switzerland.
- Department of Cell Physiology and Metabolism, Geneva Medical Centre, CH1211 Geneva, Switzerland.
| | - Chloé Chrétien
- Department of Cell Physiology and Metabolism, Geneva Medical Centre, CH1211 Geneva, Switzerland.
| | - Aurélie Caillon
- Laboratory of Metabolism, Department of Medicine Specialties, Faculty of Medicine, University of Geneva, CH1211 Geneva, Switzerland.
- Department of Cell Physiology and Metabolism, Geneva Medical Centre, CH1211 Geneva, Switzerland.
| | - Françoise Rohner-Jeanrenaud
- Laboratory of Metabolism, Department of Medicine Specialties, Faculty of Medicine, University of Geneva, CH1211 Geneva, Switzerland.
- Department of Cell Physiology and Metabolism, Geneva Medical Centre, CH1211 Geneva, Switzerland.
| | - Jordi Altirriba
- Laboratory of Metabolism, Department of Medicine Specialties, Faculty of Medicine, University of Geneva, CH1211 Geneva, Switzerland.
- Department of Cell Physiology and Metabolism, Geneva Medical Centre, CH1211 Geneva, Switzerland.
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Seelke AM, Rhine MA, Khun K, Shweyk AN, Scott AM, Bond JM, Graham JL, Havel PJ, Wolden-Hanson T, Bales KL, Blevins JE. Intranasal oxytocin reduces weight gain in diet-induced obese prairie voles. Physiol Behav 2018; 196:67-77. [PMID: 30144467 DOI: 10.1016/j.physbeh.2018.08.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 08/17/2018] [Accepted: 08/19/2018] [Indexed: 12/17/2022]
Abstract
Oxytocin (OT) elicits weight loss in diet-induced obese (DIO) rodents, nonhuman primates and humans by reducing food intake and increasing energy expenditure. In addition to being important in the regulation of energy balance, OT is involved in social behaviors including parent-infant bonds, friendships, and pair bonds. However, the impact of social context on susceptibility to diet-induced obesity (DIO) and feeding behavior (including food sharing) has not been investigated in a rodent model that forms strong social bonds (i.e. prairie vole). Our goals were to determine in Prairie voles (Microtus ochrogaster) whether i) social context impacts susceptibility to DIO and ii) chronic intranasal OT reverses DIO. Voles were housed in divided cages with holes in the divider and paired with a same-sex animal with either the same food [high fat diet (HFD)/HFD, [low fat diet (LFD; chow)/chow], or the opposite food (HFD/chow or chow/HFD) for 19 weeks. HFD-fed voles pair-housed with voles maintained on the HFD demonstrated increased weight relative to pair-housed voles that were both maintained on chow. The study was repeated to determine the impact of social context on DIO susceptibility and body composition when animals are maintained on purified sugar-sweetened HFD and LFD to enhance palatability. As before, we found that voles demonstrated higher weight gain on the HFD/HFD housing paradigm, in part, through increased energy intake and the weight gain was a consequence of an increase in fat mass. However, HFD-fed animals housed with LFD-fed animals (and vice versa) showed intermediate patterns of weight gain and evidence of food sharing. Of translational importance is the finding that chronic intranasal OT appeared to reduce weight gain in DIO voles through a decrease in fat mass with no reduction in lean body mass. These effects were associated with transient reductions in food intake and increased food sharing. These findings identify a role of social context in the pathogenesis of DIO and indicate that chronic intranasal OT treatment reduces weight gain and body fat mass in DIO prairie voles, in part, by reducing food intake.
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Affiliation(s)
- Adele M Seelke
- Department of Psychology, University of California, Davis, CA, USA
| | - Maya A Rhine
- Department of Psychology, University of California, Davis, CA, USA
| | - Konterri Khun
- Department of Psychology, University of California, Davis, CA, USA
| | - Amira N Shweyk
- Department of Psychology, University of California, Davis, CA, USA
| | | | - Jessica M Bond
- Department of Psychology, University of California, Davis, CA, USA
| | - James L Graham
- Department of Nutrition and Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Peter J Havel
- Department of Nutrition and Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Tami Wolden-Hanson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA
| | - Karen L Bales
- Department of Psychology, University of California, Davis, CA, USA
| | - James E Blevins
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA.
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Freeman SM, Ngo J, Singh B, Masnaghetti M, Bales KL, Blevins JE. Effects of Chronic Oxytocin Administration and Diet Composition on Oxytocin and Vasopressin 1a Receptor Binding in the Rat Brain. Neuroscience 2018; 392:241-251. [PMID: 30071278 DOI: 10.1016/j.neuroscience.2018.07.037] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 07/19/2018] [Accepted: 07/20/2018] [Indexed: 12/19/2022]
Abstract
Oxytocin (OT) elicits weight loss in diet-induced obese (DIO) rodents, nonhuman primates, and humans, in part, by reducing food intake. Chronic OT administration produces more sustained weight loss in high-fat diet (HFD)-fed DIO rodents relative to chow-fed controls, but the reasons for this effect remain unclear. We hypothesized that HFD-induced obesity is associated with elevated OT receptor (OXTR) binding in brain regions where OT is known to cause decreased food intake and that this sensitized neural system is one mechanism by which OT preferentially elicits weight loss in DIO rodents. We therefore determined the impact of diet (HFD vs chow) and drug treatment (chronic OT infusion vs vehicle) on (1) OXTR binding in hindbrain and forebrain sites where OT suppresses food intake relative to control sites that express OXTR and (2) forebrain vasopressin 1a receptor (AVPR1a) density to evaluate the specificity of any OT effects. Using quantitative receptor autoradiography, we found that (1) diet composition failed to alter OXTR or AVPR1a binding; (2) chronic OT treatment produced largely global reductions in forebrain OXTR and AVPR1a binding without significantly altering hindbrain OXTR binding. These findings suggest that forebrain OXTR and AVPR1a are down-regulated in response to chronic OT treatment. Given that chronic intranasal OT may be used as a therapeutic strategy to treat obesity, future studies should consider the potential downregulatory effect that chronic treatment can have across forebrain and hindbrain nonapeptide receptors and assess the potential contribution of both receptor subtypes to the outcome measures.
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Affiliation(s)
- Sara M Freeman
- Department of Psychology, University of California, Davis, CA, USA
| | - Julie Ngo
- Department of Psychology, University of California, Davis, CA, USA
| | - Bhavdeep Singh
- Department of Psychology, University of California, Davis, CA, USA
| | | | - Karen L Bales
- Department of Psychology, University of California, Davis, CA, USA
| | - James E Blevins
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA.
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Pataky Z, Guessous I, Caillon A, Golay A, Rohner-Jeanrenaud F, Altirriba J. Variable oxytocin levels in humans with different degrees of obesity and impact of gastric bypass surgery. Int J Obes (Lond) 2018; 43:1120-1124. [PMID: 30006581 DOI: 10.1038/s41366-018-0150-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 05/21/2018] [Accepted: 06/03/2018] [Indexed: 01/04/2023]
Abstract
Exogenous oxytocin administration in obese mice, rats, and monkeys was shown to induce sustained weight loss, mostly due to a decrease in fat mass, accompanied by an improvement of glucose metabolism. A pilot study in obese humans confirmed the weight-reducing effect of oxytocin. Knowledge about circulating oxytocin levels in human obesity might help indicating which obese subjects could potentially benefit from an oxytocin treatment. Conclusive results on this topic are missing. The aim of this study was to measure circulating oxytocin levels in lean (n = 37) and obese (n = 72) individuals across a wide range of body mass index (BMI) values (18.5-60 kg/m2) and to determine the impact of pronounced body weight loss following gastric bypass surgery in 12 morbidly obese patients. We observed that oxytocin levels were unchanged in overweight and in class I and II obese subjects and only morbidly obese patients (obesity class III, BMI > 40 kg/m2) exhibited significantly higher levels than lean individuals, with no modification 1 year after gastric bypass surgery, despite substantial body weight loss. In conclusion, morbidly obese subjects present elevated oxytocin levels which were unaltered following pronounced weight loss.
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Affiliation(s)
- Zoltan Pataky
- Service of Therapeutic Education for Chronic Diseases, WHO Collaborating Centre, University Hospitals of Geneva and University of Geneva, Geneva, Switzerland
| | - Idris Guessous
- Unit of Population Epidemiology, Department of Community Medicine, Primary Care and Emergency Medicine, Division of Primary Care Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Aurélie Caillon
- Laboratory of Metabolism, Department of Medicine Specialties, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Alain Golay
- Service of Therapeutic Education for Chronic Diseases, WHO Collaborating Centre, University Hospitals of Geneva and University of Geneva, Geneva, Switzerland
| | - Françoise Rohner-Jeanrenaud
- Laboratory of Metabolism, Department of Medicine Specialties, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Jordi Altirriba
- Laboratory of Metabolism, Department of Medicine Specialties, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
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Miller J. The potential of oxytocin for the treatment of hyperphagia in Prader-Willi Syndrome. Expert Opin Orphan Drugs 2018. [DOI: 10.1080/21678707.2018.1451326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Jennifer Miller
- Department of Pediatrics, Division of Endocrinology, University of Florida, Gainesville, FL, USA
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Leslie M, Silva P, Paloyelis Y, Blevins J, Treasure J. A Systematic Review and Quantitative Meta-Analysis of Oxytocin's Effects on Feeding. J Neuroendocrinol 2018; 30:10.1111/jne.12584. [PMID: 29480934 PMCID: PMC6292740 DOI: 10.1111/jne.12584] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 02/20/2018] [Indexed: 12/15/2022]
Abstract
PURPOSE Oxytocin's anorexigenic effects have been widely documented and accepted; however, no paper has yet used the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines to compile previous findings in a single systematic review and quantitative meta-analysis. The current paper aimed to identify published and unpublished studies examining the effects of oxytocin on energy intake in animals and humans, and the factors that moderate this effect. METHODS Web of Science, Pub Med, and Ovid were searched for published and unpublished studies reporting the effects of oxytocin on energy intake in wild-type animals and in humans, when administered in the absence of other active drugs or surgery. RESULTS 2049 articles were identified through the original systematic literature search, from which 54 articles were identified as relevant for inclusion in this review. An additional 3 relevant articles were identified in a later update of the literature search. Overall, a single-dose of oxytocin was found to reduce feeding in animals. Despite several individual studies which found that this effect persists to the end of the third week of chronic administration in rodent models, overall, this anorexigenic effect did not hold in the meta-analyses testing the effects of chronic administration. There was no overall effect of oxytocin on energy intake in humans, although a trend was identified for oxytocin to reduce consumption of solid foods. CONCLUSIONS Oxytocin reduces energy intake when administered as a single dose. Oxytocin can inhibit feeding over two- to three-week periods in rodent models. These effects typically do not persist beyond the third week of treatment. The anorexigenic effect of oxytocin is moderated by pregnant status, dose, method of administration, and diet composition. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Monica Leslie
- Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King’s College London (KCL), London, UK
| | - Paulo Silva
- Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King’s College London (KCL), London, UK
| | - Yannis Paloyelis
- Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King’s College London (KCL), London, UK
| | - James Blevins
- Department of Veterans Affairs Medical Center, Office of Research and Development Medical Research Service, VA Puget Sound Health Care System, Seattle, WA, USA
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA
| | - Janet Treasure
- Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King’s College London (KCL), London, UK
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Hsu EA, Miller JL, Perez FA, Roth CL. Oxytocin and Naltrexone Successfully Treat Hypothalamic Obesity in a Boy Post-Craniopharyngioma Resection. J Clin Endocrinol Metab 2018; 103:370-375. [PMID: 29220529 DOI: 10.1210/jc.2017-02080] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 12/01/2017] [Indexed: 11/19/2022]
Abstract
CONTEXT Hypothalamic obesity, a treatment-resistant condition common to survivors of craniopharyngioma (CP), is strongly associated with a poor quality of life in this population. Oxytocin (OT), a hypothalamic neuropeptide, has been shown to play a role in the regulation of energy balance and to have anorexigenic effects in animal studies. Naltrexone (NAL), an opiate antagonist, has been shown to deter hedonic eating and to potentiate OT's effects. DESIGN In this parent-observed study, we tested the administration of intranasal OT for 10 weeks (phase 1), followed by a combination of intranasal OT and NAL for 38 weeks (phase 2) in a 13-year-old male with confirmed hypothalamic obesity and hyperphagia post-CP resection. Treatment resulted in 1) reduction in body mass index (BMI) z score from 1.77 to 1.49 over 10 weeks during phase 1; 2) reduction in BMI z score from 1.49 to 0.82 over 38 weeks during phase 2; 3) reduced hyperphagia during phases 1 and 2; 4) continued hedonic high-carbohydrate food-seeking in the absence of hunger during phases 1 and 2; and 5) sustained weight reduction during decreased parental monitoring and free access to unlocked food in the home during the last 10 weeks of phase 2. CONCLUSION This successful intervention of CP-related hypothalamic obesity and hyperphagia by OT alone and in combination with NAL is promising for conducting future studies of this treatment-recalcitrant form of obesity.
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Affiliation(s)
- Eugenie A Hsu
- Department of Psychiatry, Kaiser Permanente Medical Center, Oakland, California
| | - Jennifer L Miller
- Division of Endocrinology, Department of Pediatrics, University of Florida, Gainesville, Florida
| | - Francisco A Perez
- Department of Radiology, Seattle Children's Hospital and Research Institute, Seattle, Washington
| | - Christian L Roth
- Center for Integrative Brain Research, Seattle Children's Hospital and Research Institute, Seattle, Washington
- Department of Pediatric Endocrinology, Seattle Children's Hospital and Research Institute, Seattle, Washington
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Maejima Y, Yokota S, Nishimori K, Shimomura K. The Anorexigenic Neural Pathways of Oxytocin and Their Clinical Implication. Neuroendocrinology 2018; 107:91-104. [PMID: 29660735 DOI: 10.1159/000489263] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 04/15/2018] [Indexed: 12/21/2022]
Abstract
Oxytocin was discovered in 1906 as a peptide that promotes delivery and milk ejection; however, its additional physiological functions were determined 100 years later. Many recent articles have reported newly discovered effects of oxytocin on social communication, bonding, reward-related behavior, adipose tissue, and muscle and food intake regulation. Because oxytocin neurons project to various regions in the brain that contribute to both feeding reward (hedonic feeding) and the regulation of energy balance (homeostatic feeding), the mechanisms of oxytocin on food intake regulation are complicated and largely unknown. Oxytocin neurons in the paraventricular nucleus (PVN) receive neural projections from the arcuate nucleus (ARC), which is an important center for feeding regulation. On the other hand, these neurons in the PVN and supraoptic nucleus project to the ARC. PVN oxytocin neurons also project to the brain stem and the reward-related limbic system. In addition to this, oxytocin induces lipolysis and decreases fat mass. However, these effects in feeding and adipose tissue are known to be dependent on body weight (BW). Oxytocin treatment is more effective in food intake regulation and fat mass decline for individuals with leptin resistance and higher BW, but is known to be less effective in individuals with normal BW. In this review, we present in detail the recent findings on the physiological role of oxytocin in feeding regulation and the anorexigenic neural pathway of oxytocin neurons, as well as the advantage of oxytocin usage for anti-obesity treatment.
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Affiliation(s)
- Yuko Maejima
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Shoko Yokota
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Katsuhiko Nishimori
- Department of Molecular and Cell Biology, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan
| | - Kenju Shimomura
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, Fukushima, Japan
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