1
|
McGlone ER, Hope DCD, Davies I, Dore M, Goldin R, Jones B, Liu Z, Li JV, Vorkas PA, Khoo B, Carling D, Minnion J, Bloom SR, Tan TMM. Chronic treatment with glucagon-like peptide-1 and glucagon receptor co-agonist causes weight loss-independent improvements in hepatic steatosis in mice with diet-induced obesity. Biomed Pharmacother 2024; 176:116888. [PMID: 38861859 DOI: 10.1016/j.biopha.2024.116888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Revised: 05/28/2024] [Accepted: 06/03/2024] [Indexed: 06/13/2024] Open
Abstract
OBJECTIVES Co-agonists at the glucagon-like peptide-1 and glucagon receptors (GLP1R/GCGR) show promise as treatments for metabolic dysfunction-associated steatotic liver disease (MASLD). Although most co-agonists to date have been heavily GLP1R-biased, glucagon directly acts on the liver to reduce fat content. The aims of this study were to investigate a GCGR-biased co-agonist as treatment for hepatic steatosis in mice. METHODS Mice with diet-induced obesity (DIO) were treated with Dicretin, a GLP1/GCGR co-agonist with high potency at the GCGR, Semaglutide (GLP1R monoagonist) or food restriction over 24 days, such that their weight loss was matched. Hepatic steatosis, glucose tolerance, hepatic transcriptomics, metabolomics and lipidomics at the end of the study were compared with Vehicle-treated mice. RESULTS Dicretin lead to superior reduction of hepatic lipid content when compared to Semaglutide or equivalent weight loss by calorie restriction. Markers of glucose tolerance and insulin resistance improved in all treatment groups. Hepatic transcriptomic and metabolomic profiling demonstrated many changes that were unique to Dicretin-treated mice. These include some known targets of glucagon signaling and others with as yet unclear physiological significance. CONCLUSIONS Our study supports the development of GCGR-biased GLP1/GCGR co-agonists for treatment of MASLD and related conditions.
Collapse
Affiliation(s)
- Emma Rose McGlone
- Department of Surgery and Cancer, Imperial College London, London, UK; Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - David C D Hope
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Iona Davies
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Marian Dore
- Genomics facility, MRC Laboratory of Medical Sciences (LMS), Imperial College London, London, UK
| | - Rob Goldin
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Ben Jones
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Zhigang Liu
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Jia V Li
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Panagiotis A Vorkas
- Institute of Applied Biosciences, Centre for Research and Technology Hellas (INAB|CERTH), Thessaloniki 57001, Greece; School of Cardiovascular and Metabolic Medicine & Sciences, King's College London, London, UK
| | - Bernard Khoo
- Endocrinology, Division of Medicine, University College London, London, UK
| | - David Carling
- Cellular Stress group, MRC LMS, Imperial College London, London, UK
| | - James Minnion
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Stephen R Bloom
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Tricia M-M Tan
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
| |
Collapse
|
2
|
Lee J, Kim WK. Applications of Enteroendocrine Cells (EECs) Hormone: Applicability on Feed Intake and Nutrient Absorption in Chickens. Animals (Basel) 2023; 13:2975. [PMID: 37760373 PMCID: PMC10525316 DOI: 10.3390/ani13182975] [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: 08/14/2023] [Revised: 09/09/2023] [Accepted: 09/13/2023] [Indexed: 09/29/2023] Open
Abstract
This review focuses on the role of hormones derived from enteroendocrine cells (EECs) on appetite and nutrient absorption in chickens. In response to nutrient intake, EECs release hormones that act on many organs and body systems, including the brain, gallbladder, and pancreas. Gut hormones released from EECs play a critical role in the regulation of feed intake and the absorption of nutrients such as glucose, protein, and fat following feed ingestion. We could hypothesize that EECs are essential for the regulation of appetite and nutrient absorption because the malfunction of EECs causes severe diarrhea and digestion problems. The importance of EEC hormones has been recognized, and many studies have been carried out to elucidate their mechanisms for many years in other species. However, there is a lack of research on the regulation of appetite and nutrient absorption by EEC hormones in chickens. This review suggests the potential significance of EEC hormones on growth and health in chickens under stress conditions induced by diseases and high temperature, etc., by providing in-depth knowledge of EEC hormones and mechanisms on how these hormones regulate appetite and nutrient absorption in other species.
Collapse
Affiliation(s)
| | - Woo Kyun Kim
- Department of Poultry Science, University of Georgia, Athens, GA 30602, USA;
| |
Collapse
|
3
|
Wei MD, Huang YY, Zeng Y, Lan YX, Lu K, Wang Y, Chen WY. Homocysteine Modulates Social Isolation-Induced Depressive-Like Behaviors Through BDNF in Aged Mice. Mol Neurobiol 2023; 60:4924-4934. [PMID: 37198386 PMCID: PMC10191402 DOI: 10.1007/s12035-023-03377-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 05/01/2023] [Indexed: 05/19/2023]
Abstract
Social isolation is an unpleasant experience associated with an increased risk of mental disorders. Exploring whether these experiences affect behaviors in aged people is particularly important, as the elderly is very likely to suffer from periods of social isolation during their late-life. In this study, we analyzed the depressive-like behaviors, plasma concentrations of homocysteine (Hcy), and brain-derived neurotropic factor (BDNF) levels in aged mice undergoing social isolation. Results showed that depressive-like behavioral performance and decreased BDNF level were correlated with increased Hcy levels that were detected in 2-month isolated mice. Elevated Hcy induced by high methionine diet mimicked the depressive-like behaviors and BDNF downregulation in the same manner as social isolation, while administration of vitamin B complex supplements to reduce Hcy alleviated the depressive-like behaviors and BDNF reduction in socially isolated mice. Altogether, our results indicated that Hcy played a critical role in social isolation-induced depressive-like behaviors and BDNF reduction, suggesting the possibility of Hcy as a potential therapeutic target and vitamin B intake as a potential value in the prevention of stress-induced depression.
Collapse
Affiliation(s)
- Mei-Dan Wei
- Department of Pharmacy, The Third Affiliated Hospital of Southern Medical University, Guangzhou, 510630, Guangdong, China.
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, 510515, Guangdong, China.
| | - Ya-Yan Huang
- Department of Pharmacy, The Third Affiliated Hospital of Southern Medical University, Guangzhou, 510630, Guangdong, China
| | - Ying Zeng
- Department of Pharmacy, The Third Affiliated Hospital of Southern Medical University, Guangzhou, 510630, Guangdong, China
| | - Yan-Xian Lan
- Department of Pharmacy, Minzu Hospital of Guangxi Zhuang Autonomous Region, Nanning, 530001, Guangxi, China
| | - Kun Lu
- Department of Pediatric Orthopaedic, Zhengzhou Orthopaedics Hospital, Zhengzhou, 450052, Henan, China
| | - Yan Wang
- Department of Pharmacy, The Third Affiliated Hospital of Southern Medical University, Guangzhou, 510630, Guangdong, China
| | - Wen-Ying Chen
- Department of Pharmacy, The Third Affiliated Hospital of Southern Medical University, Guangzhou, 510630, Guangdong, China
| |
Collapse
|
4
|
Geisler CE, Hayes MR. Metabolic hormone action in the VTA: Reward-directed behavior and mechanistic insights. Physiol Behav 2023; 268:114236. [PMID: 37178855 PMCID: PMC10330780 DOI: 10.1016/j.physbeh.2023.114236] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 04/10/2023] [Accepted: 05/10/2023] [Indexed: 05/15/2023]
Abstract
Dysfunctional signaling in midbrain reward circuits perpetuates diseases characterized by compulsive overconsumption of rewarding substances such as substance abuse, binge eating disorder, and obesity. Ventral tegmental area (VTA) dopaminergic activity serves as an index for how rewarding stimuli are perceived and triggers behaviors necessary to obtain future rewards. The evolutionary linking of reward with seeking and consuming palatable foods ensured an organism's survival, and hormone systems that regulate appetite concomitantly developed to regulate motivated behaviors. Today, these same mechanisms serve to regulate reward-directed behavior around food, drugs, alcohol, and social interactions. Understanding how hormonal regulation of VTA dopaminergic output alters motivated behaviors is essential to leveraging therapeutics that target these hormone systems to treat addiction and disordered eating. This review will outline our current understanding of the mechanisms underlying VTA action of the metabolic hormones ghrelin, glucagon-like peptide-1, amylin, leptin, and insulin to regulate behavior around food and drugs of abuse, highlighting commonalities and differences in how these five hormones ultimately modulate VTA dopamine signaling.
Collapse
Affiliation(s)
- Caroline E Geisler
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Matthew R Hayes
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
5
|
Lopez TJ, Barcelos MA, Treesukosol Y. The administration of Exendin-4 and CCK affects food intake differentially in female and male rats tested on an alternate day fasting paradigm. Neurosci Lett 2023; 808:137275. [PMID: 37116572 DOI: 10.1016/j.neulet.2023.137275] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/04/2023] [Accepted: 04/21/2023] [Indexed: 04/30/2023]
Abstract
Alternate day fasting (ADF) which involves the repetition of a 2-day cycle of a day of free access to food followed by a day of limited or no access to food, is an effective dietary intervention for weight loss in both humans and rats. We have previously reported that when presented with a high energy (HE) and standard chow diet, rats maintained on an ADF schedule displayed decreased HE diet preference compared to controls. Both male and female ADF rats increased overall intake of chow. However, this increase was driven by both meal size and meal number for males and only number of meals for females. Administration of cholecystokinin (CCK) or the glucagon-like peptide 1 (GLP-1) receptor agonist Exendin-4 (Ex-4) reduces food intake. It appears that CCK decreases food intake primarily through satiety signals whereas GLP-1 signaling may reduce intake by satiety and reward cues. Here, female and male rats were administered (i.p.) saline, 3.0 µg/kg Ex-4 (3 h before test), 3.0 µg/kg CCK (15 min before test) or a combination of both. Next, all rats were presented 23-h access to both HE diet and chow following food-restriction (ADF) or free access to chow (CON). Compared to saline-control sessions, administration of the combination of Ex-4 and CCK, but not Ex-4 or CCK alone, resulted in a decrease in both HE and chow intake early in the session for male ADF rats but the combination primarily decreased chow diet intake early in the session for female ADF rats. Thus, it appears that under these energy homeostatic conditions, administration of Ex-4 or CCK alone does not affect intake in ADF rats, but the combination produces decreases in feeding that are more than the sum of their individual effects. These findings support a role for the combination of GLP-1 and CCK signaling in the changes in diet preference induced by an alternate day fasting paradigm differentially in female and male rats.
Collapse
Affiliation(s)
- Taityana J Lopez
- Department of Psychology, California State University Long Beach, Long Beach CA 90840, USA
| | - Marc A Barcelos
- Department of Psychology, California State University Long Beach, Long Beach CA 90840, USA
| | - Yada Treesukosol
- Department of Psychology, California State University Long Beach, Long Beach CA 90840, USA.
| |
Collapse
|
6
|
Przybysz JT, DiBrog AM, Kern KA, Mukherjee A, Japa JE, Waite MH, Mietlicki-Baase EG. Macronutrient intake: Hormonal controls, pathological states, and methodological considerations. Appetite 2023; 180:106365. [PMID: 36347305 PMCID: PMC10563642 DOI: 10.1016/j.appet.2022.106365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 10/31/2022] [Accepted: 11/01/2022] [Indexed: 11/07/2022]
Abstract
A plethora of studies to date has examined the roles of feeding-related peptides in the control of food intake. However, the influence of these peptides on the intake of particular macronutrient constituents of food - carbohydrate, fat, and protein - has not been as extensively addressed in the literature. Here, the roles of several feeding-related peptides in controlling macronutrient intake are reviewed. Next, the relationship between macronutrient intake and diseases including diabetes mellitus, obesity, and eating disorders are examined. Finally, some key considerations in macronutrient intake research are discussed. We hope that this review will shed light onto this underappreciated topic in ingestive behavior research and will help to guide further scientific investigation in this area.
Collapse
Affiliation(s)
- Johnathan T Przybysz
- Exercise and Nutrition Sciences, School of Public Health and Health Professions, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Adrianne M DiBrog
- Exercise and Nutrition Sciences, School of Public Health and Health Professions, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Katherine A Kern
- Exercise and Nutrition Sciences, School of Public Health and Health Professions, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Ashmita Mukherjee
- Psychology, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA
| | - Jason E Japa
- Biotechnical and Clinical Laboratory Sciences, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Mariana H Waite
- Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Elizabeth G Mietlicki-Baase
- Exercise and Nutrition Sciences, School of Public Health and Health Professions, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA; Center for Ingestive Behavior Research, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA.
| |
Collapse
|
7
|
DiBrog AM, Kern KA, Mukherjee A, Przybysz JT, Mietlicki-Baase EG. The alpha-7 nicotinic acetylcholine receptor agonist GTS-21 does not affect food intake in rats. Pharmacol Biochem Behav 2022; 219:173444. [PMID: 35944617 PMCID: PMC10577676 DOI: 10.1016/j.pbb.2022.173444] [Citation(s) in RCA: 2] [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: 03/28/2022] [Revised: 08/02/2022] [Accepted: 08/03/2022] [Indexed: 10/16/2022]
Abstract
Obesity is a prevalent disease, but effective treatments remain limited. Agonists of the alpha-7 nicotinic acetylcholine receptor (α7nAChR) promote negative energy balance in mice, but these effects are not well-studied in rats. We tested the hypothesis that the α7nAChR agonist GTS-21 would decrease food intake and body weight in adult male Sprague Dawley rats. Contrary to our hypothesis, acute systemic administration of GTS-21 produced no significant effects on chow or high-fat diet (HFD) intake. Acute intracerebroventricular (ICV) GTS-21 also had no impact on chow intake, and actually increased body weight at the highest dose tested. Previous studies suggest that GTS-21 engages the food intake-suppressive glucagon-like peptide-1 (GLP-1) system in mice. As there are known species differences in GLP-1 physiology between mice and rats, we tested the ability of GTS-21 to elicit GLP-1 secretion in rats. Our results showed that plasma levels of total GLP-1 in rats were not significantly altered by peripheral GTS-21 injection. These results represent an advance in understanding how α7nAChR activation impacts energy balance control in rodents and suggest that there may be important differences between rats and mice in the ability of GTS-21/α7nAChR activation to increase secretion of GLP-1.
Collapse
Affiliation(s)
- Adrianne M DiBrog
- Exercise and Nutrition Sciences, University at Buffalo, United States of America
| | - Katherine A Kern
- Exercise and Nutrition Sciences, University at Buffalo, United States of America
| | | | - Johnathan T Przybysz
- Exercise and Nutrition Sciences, University at Buffalo, United States of America
| | - Elizabeth G Mietlicki-Baase
- Exercise and Nutrition Sciences, University at Buffalo, United States of America; Center for Ingestive Behavior Research, University at Buffalo, United States of America.
| |
Collapse
|
8
|
Takeda K, Aotani D, Kuga Y, Jinno T, Guo T, Ogawa K, Shimizu Y, Hattori R, Yagi T, Koyama H, Matsumura S, Kataoka H, Tanaka T. A mouse model of weight gain after nicotine withdrawal. Biochem Biophys Res Commun 2022; 588:140-146. [PMID: 34954521 DOI: 10.1016/j.bbrc.2021.12.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 12/18/2021] [Indexed: 11/17/2022]
Abstract
Smoking cessation increases body weight. The underlying mechanisms, however, have not been fully understood. We here report an establishment of a mouse model that exhibits an augmented body weight gain after nicotine withdrawal. High fat diet-fed mice were infused with nicotine for two weeks, and then with vehicle for another two weeks using osmotic minipumps. Body weight increased immediately after nicotine cessation and was significantly higher than that of mice continued on nicotine. Mice switched to vehicle consumed more food than nicotine-continued mice during the first week of cessation, while oxygen consumption was comparable. Elevated expression of orexigenic agouti-related peptide was observed in the hypothalamic appetite center. Pair-feeding experiment revealed that the accelerated weight gain after nicotine withdrawal is explained by enhanced energy intake. As a showcase of an efficacy of pharmacologic intervention, exendin-4 was administered and showed a potent suppression of energy intake and weight gain in mice withdrawn from nicotine. Our current model provides a unique platform for the investigation of the changes of energy regulation after smoking cessation.
Collapse
Affiliation(s)
- Katsushi Takeda
- Department of Gastroenterology and Metabolism, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Daisuke Aotani
- Department of Gastroenterology and Metabolism, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan.
| | - Yusuke Kuga
- Department of Gastroenterology and Metabolism, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Tomoki Jinno
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Tingting Guo
- Department of Gastroenterology and Metabolism, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Kento Ogawa
- Department of Gastroenterology and Metabolism, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Yuki Shimizu
- Department of Gastroenterology and Metabolism, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Rei Hattori
- Department of Gastroenterology and Metabolism, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Takashi Yagi
- Department of Gastroenterology and Metabolism, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Hiroyuki Koyama
- Department of Gastroenterology and Metabolism, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Shigenobu Matsumura
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan; Graduate School of Comprehensive Rehabilitation, Osaka Prefecture University, 3-7-30 Habikino, Habikino, Osaka, 583-8555, Japan
| | - Hiromi Kataoka
- Department of Gastroenterology and Metabolism, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Tomohiro Tanaka
- Department of Gastroenterology and Metabolism, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan.
| |
Collapse
|
9
|
Abstract
Administration of cholecystokinin (CCK) or the glucagon-like peptide 1 (GLP-1) receptor agonist Exendin-4 (Ex-4) reduces food intake. Findings in the literature suggest CCK reduces intake primarily as a satiety signal whereas GLP-1 may play a role in both satiety and reward-related feeding signals. Compounds that humans describe as âsweetâ and âfattyâ are palatable yet are signaled via separate transduction pathways. Here, unconditioned lick responses to sucrose and intralipid were measured in a brief-access lick procedure in food-restricted male rats in response to i.p. administration of Ex-4 (3 h before test), CCK (30 min before test), or a combination of both. The current experimental design measures lick responses to water and varying concentrations of both sucrose (0.03, 0.1, and 0.5 M) and intralipid (0.2%, 2%, and 20%) during 10-s trials across a 30-min single test session. This design minimized postingestive influences. Compared with saline-injected controls, CCK (1.0, 3.0, or 6.0 µg/kg) did not change lick responses to sucrose or intralipid. Number of trials initiated and lick responses to both sucrose and intralipid were reduced in rats injected with 3.0 µg/kg, but not 1.0 µg/kg Ex-4. The supplement of CCK did not alter lick responses or trials initiated compared with Ex-4 administration alone. These findings support a role for GLP-1 but not CCK in the oral responsiveness to palatable stimuli. Furthermore, Ex-4-induced reductions were observed for both sucrose and intralipid, compounds representing âsweetâ and âfat,â respectively.
Collapse
Affiliation(s)
- Yada Treesukosol
- Department of Psychology, California State University Long Beach, Long Beach, CA 90840, United States
- Corresponding author: Department of Psychology, California State University Long Beach, 1250 Bellflower Blvd, Long Beach, CA 90840-090, United States.
| | - Timothy H Moran
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| |
Collapse
|
10
|
Expression of glucagon-like peptide 1 receptor in neuropeptide Y neurons of the arcuate nucleus in mice. Brain Struct Funct 2021; 227:77-87. [PMID: 34596755 DOI: 10.1007/s00429-021-02380-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 09/02/2021] [Indexed: 10/20/2022]
Abstract
Glucagon-like peptide 1 (GLP-1) and its agonists exert anorexigenic effect at least partly via acting on GLP-1 receptors (GLP-1R) in the arcuate nucleus (ARC). While the anorexigenic, proopiomelanocortin (POMC) neurons of the ARC were shown previously to express GLP-1R, the putative GLP-1R-content of the orexigenic, neuropeptide Y (NPY) neurons remained so far undetected. As GLP-1R is abundant in the ventromedial ARC, where NPY neurons are located; here, we address the possibility that GLP-1 can act directly on the orexigenic NPY system via GLP-1R. Double-labeling immunocytochemistry and in situ hybridization were performed on tissues of adult male mice to detect GLP-1R in NPY neurons. In double-immunolabeled preparations, GLP-1R-immunoreactivity was observed in NPY neurons and in axons ensheathing the majority of NPY neurons. Ultrastructural studies confirmed that GLP-1R-immunoreactivity is associated with the outer membrane of NPY perikarya as well as with axons forming symmetric type, inhibitory synapses on NPY-containing neurons. Double-labeling in situ hybridization experiments demonstrated the expression of GLP-1R mRNA in approximately 20% of NPY mRNA-containing neurons of the ARC. In summary, our data demonstrate the presence of GLP-1R protein and mRNA in NPY neurons of ARC and also reveal the innervation of NPY neurons by GLP-1R-containing inhibitory neurons. These observations suggest that GLP-1 signaling can influence NPY neurons both directly and indirectly. Furthermore, GLP-1 signaling on energy homeostasis appears to involve both direct and indirect effects of GLP-1 on the orexigenic NPY neurons, in addition to the previously known effects via the anorexigenic POMC neuronal system.
Collapse
|
11
|
Peng X, Shi X, Huang J, Zhang S, Yan Y, Ma D, Xu W, Xu W, Dong K, Tao J, Li M, Yang Y. Exendin-4 Improves Cognitive Function of Diabetic Mice via Increasing Brain Insulin Synthesis. Curr Alzheimer Res 2021; 18:546-557. [PMID: 34587885 DOI: 10.2174/1567205018666210929150004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 06/16/2021] [Accepted: 08/24/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND AND OBJECTIVE Type 2 diabetes(T2D) patients are more prone to develop Alzheimer's disease (AD). We have previously shown that Glucagon-like peptide-1 receptor agon- ist exendin-4 (Ex-4) reduces tau hyperphosphorylation in T2D animals through upregulating in- sulin signaling, and peripheral injected Ex-4 increases insulin levels in the T2D brain. This study aims to further clarify whether the elevated insulin in the brain is produced by nerve cells under the action of Ex-4. METHODS The neuronal cell line-HT22 was treated with Ex-4 under high glucose or normal cultiva- tion, and the number of insulin-positive cells as well as the expression levels of insulin synthesis-re- lated genes were examined. The db/db mice were treated with a peripheral injection of Ex-4 and/or intracerebroventricular (ICV) injection of siRNA to inhibit the expression of insulin synthesis-relat- ed genes and the behavior tests were carried on. Finally, plasma glucose, cerebrospinal fluid (CSF) glucose, CSF insulin, phosphorylation of tau, phosphorylation of AKT and GSK-3β of db/db mice were detected. RESULTS We found that Ex-4 promoted the expression of insulin synthesis-related genes and in- duced an obvious increase of insulin-positive HT-22 neuronal cells in a high glucose environment. Peripheral injection of Ex-4 improved the cognitive function of db/db mice and increased brain in- sulin levels which activated brain insulin signaling and subsequently alleviated tau hyperphosphory- lation. However, when siRNA-neurod1 was injected to block insulin synthesis, the cognitive func- tion of db/db mice was not improved under the action of Ex-4 anymore. Moreover, the brain in- sulin levels dropped to an extremely low level, and the phosphorylation level of tau increased signi- ficantly. CONCLUSION This study demonstrated that Ex-4 improved cognition function by promoting brain in- sulin synthesis followed by the activation of brain insulin signaling and alleviation of tau hyper- phosphorylation.
Collapse
Affiliation(s)
- Xuemin Peng
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| | - Xiaoli Shi
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| | - Jiaojiao Huang
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| | - Shujun Zhang
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| | - Yongli Yan
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| | - Delin Ma
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| | - Weijie Xu
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| | - Weijie Xu
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| | - Kun Dong
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| | - Jing Tao
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| | - Mengni Li
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| | - Yan Yang
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei. China
| |
Collapse
|
12
|
Eren-Yazicioglu CY, Yigit A, Dogruoz RE, Yapici-Eser H. Can GLP-1 Be a Target for Reward System Related Disorders? A Qualitative Synthesis and Systematic Review Analysis of Studies on Palatable Food, Drugs of Abuse, and Alcohol. Front Behav Neurosci 2021; 14:614884. [PMID: 33536884 PMCID: PMC7848227 DOI: 10.3389/fnbeh.2020.614884] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 12/15/2020] [Indexed: 11/15/2022] Open
Abstract
The role of glucagon-like peptide 1 (GLP-1) in insulin-dependent signaling is well-known; GLP-1 enhances glucose-dependent insulin secretion and lowers blood glucose in diabetes. GLP-1 receptors (GLP-1R) are also widely expressed in the brain, and in addition to its role in neuroprotection, it affects reward pathways. This systematic review aimed to analyze the studies on GLP-1 and reward pathways and its currently identified mechanisms. Methods: “Web of Science” and “Pubmed” were searched to identify relevant studies using GLP-1 as the keyword. Among the identified 26,539 studies, 30 clinical, and 71 preclinical studies were included. Data is presented by grouping rodent studies on palatable food intake, drugs of abuse, and studies on humans focusing on GLP-1 and reward systems. Results: GLP-1Rs are located in reward-related areas, and GLP-1, its agonists, and DPP-IV inhibitors are effective in decreasing palatable food intake, along with reducing cocaine, amphetamine, alcohol, and nicotine use in animals. GLP-1 modulates dopamine levels and glutamatergic neurotransmission, which results in observed behavioral changes. In humans, GLP-1 alters palatable food intake and improves activity deficits in the insula, hypothalamus, and orbitofrontal cortex (OFC). GLP-1 reduces food cravings partially by decreasing activity to the anticipation of food in the left insula of obese patients with diabetes and may inhibit overeating by increasing activity to the consumption of food in the right OFC of obese and left insula of obese with diabetes. Conclusion: Current preclinical studies support the view that GLP-1 can be a target for reward system related disorders. More translational research is needed to evaluate its efficacy on human reward system related disorders.
Collapse
Affiliation(s)
| | - Arya Yigit
- School of Medicine, Koç University, Istanbul, Turkey
| | - Ramazan Efe Dogruoz
- Department of Neuroscience, University of Chicago, Chicago, IL, United States
| | - Hale Yapici-Eser
- Koç University, Research Center for Translational Medicine (KUTTAM), Istanbul, Turkey.,Department of Psychiatry, School of Medicine, Koç University, Istanbul, Turkey
| |
Collapse
|
13
|
Péterfi Z, Szilvásy-Szabó A, Farkas E, Ruska Y, Pyke C, Knudsen LB, Fekete C. Glucagon-Like Peptide-1 Regulates the Proopiomelanocortin Neurons of the Arcuate Nucleus both Directly and Indirectly via Presynaptic Action. Neuroendocrinology 2021; 111:986-997. [PMID: 33152734 DOI: 10.1159/000512806] [Citation(s) in RCA: 6] [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] [Received: 05/19/2020] [Accepted: 11/02/2020] [Indexed: 11/19/2022]
Abstract
Glucagon-like peptide-1 (GLP-1) exerts its anorexigenic effect at least partly via the proopiomelanocortin (POMC) neurons of the arcuate (ARC) nucleus. These neurons are known to express GLP-1 receptor (GLP-1R). The aim of the study was to determine whether in addition to its direct effect, GLP-1 also modulates how neuronal inputs can regulate the POMC neurons by acting on presynaptic terminals, ultrastructural and electrophysiological studies were performed on tissues of adult male mice. GLP-1R-immunoreactivity was associated with the cell membrane of POMC neurons and with axon terminals forming synapses on these cells. The GLP-1 analog exendin 4 (Ex4) markedly increased the firing rate of all examined POMC neurons and depolarized these cells. These effects of Ex4 were prevented by intracellular administration of the G-protein blocker guanosine 5'-[β-thio]diphosphate trilithium salt (GDP-β-S). Ex4 also influenced the miniature postsynaptic currents (mPSCs) and evoked PSCs of POMC neurons. Ex4 increased the frequency of miniature excitatory PSCs (EPSCs) and the amplitude of the evoked EPSCs in half of the POMC neurons. Ex4 increased the frequency of miniature inhibitory PSCs (IPSCs) and the amplitudes of the evoked IPSCs in one-third of neurons. These effects of Ex4 were not influenced by intracellular GDP-β-S, indicating that GLP-1 signaling directly stimulates a population of axon terminals innervating the POMC neurons. The different Ex4 responsiveness of their mPSCs indicates the heterogeneity of the POMC neurons of the ARC. In summary, our data demonstrate that in addition to its direct excitatory effect on the POMC neurons, GLP-1 signaling also facilitates the presynaptic input of these cells by acting on presynaptically localized GLP-1R.
Collapse
Affiliation(s)
- Zoltán Péterfi
- Laboratory of Integrative Neuroendocrinology, Department of Endocrine Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Anett Szilvásy-Szabó
- Laboratory of Integrative Neuroendocrinology, Department of Endocrine Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Erzsébet Farkas
- Laboratory of Integrative Neuroendocrinology, Department of Endocrine Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Yvette Ruska
- Laboratory of Integrative Neuroendocrinology, Department of Endocrine Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Charles Pyke
- Global Research, Novo Nordisk A/S, Malov, Denmark
| | | | - Csaba Fekete
- Laboratory of Integrative Neuroendocrinology, Department of Endocrine Neurobiology, Institute of Experimental Medicine, Budapest, Hungary,
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Tupper Research Institute, Tufts Medical Center, Boston, Massachusetts, USA,
| |
Collapse
|
14
|
Bodnar RJ. Endogenous opioid modulation of food intake and body weight: Implications for opioid influences upon motivation and addiction. Peptides 2019; 116:42-62. [PMID: 31047940 DOI: 10.1016/j.peptides.2019.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 03/04/2019] [Accepted: 04/08/2019] [Indexed: 12/12/2022]
Abstract
This review is part of a special issue dedicated to Opioid addiction, and examines the influential role of opioid peptides, opioid receptors and opiate drugs in mediating food intake and body weight control in rodents. This review postulates that opioid mediation of food intake was an example of "positive addictive" properties that provide motivational drives to maintain opioid-seeking behavior and that are not subject to the "negative addictive" properties associated with tolerance, dependence and withdrawal. Data demonstrate that opiate and opioid peptide agonists stimulate food intake through homeostatic activation of sensory, metabolic and energy-related In contrast, general, and particularly mu-selective, opioid receptor antagonists typically block these homeostatically-driven ingestive behaviors. Intake of palatable and hedonic food stimuli is inhibited by general, and particularly mu-selective, opioid receptor antagonists. The selectivity of specific opioid agonists to elicit food intake was confirmed through the use of opioid receptor antagonists and molecular knockdown (antisense) techniques incapacitating specific exons of opioid receptor genes. Further extensive evidence demonstrated that homeostatic and hedonic ingestive situations correspondingly altered the levels and expression of opioid peptides and opioid receptors. Opioid mediation of food intake was controlled by a distributed brain network intimately related to both the appetitive-consummatory sites implicated in food intake as well as sites intimately involved in reward and reinforcement. This emergent system appears to sustain the "positive addictive" properties providing motivational drives to maintain opioid-seeking behavior.
Collapse
Affiliation(s)
- Richard J Bodnar
- Department of Psychology, Queens College, City University of New York, United States; Psychology Doctoral Program and CUNY Neuroscience Collaborative, The Graduate Center of the City University of New York, United States.
| |
Collapse
|
15
|
Abtahi S, Howell E, Salvucci JT, Bastacky JMR, Dunn DP, Currie PJ. Exendin-4 antagonizes the metabolic action of acylated ghrelinergic signaling in the hypothalamic paraventricular nucleus. Gen Comp Endocrinol 2019; 270:75-81. [PMID: 30336120 PMCID: PMC6886705 DOI: 10.1016/j.ygcen.2018.10.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 09/19/2018] [Accepted: 10/14/2018] [Indexed: 12/11/2022]
Abstract
In the current study we investigated the interaction of hypothalamic paraventricular nucleus (PVN) glucagon-like peptide-1 (GLP-1) and ghrelin signaling in the control of metabolic function. We first demonstrated that acylated ghrelin injected directly into the PVN reliably altered the respiratory exchange ratio (RER) of adult male Sprague Dawley rats. All testing was carried out during the initial 2 h of the nocturnal cycle using an indirect open circuit calorimeter. Results indicated that acylated ghrelin induced a robust increase in RER representing a shift toward enhanced carbohydrate oxidation and reduced lipid utilization. In contrast, treatment with comparable dosing of des-acyl ghrelin failed to significantly impact metabolic activity. In separate groups of rats we subsequently investigated the ability of exendin-4 (Ex-4), a GLP-1 analogue, to alter acylated ghrelin's metabolic effects. Rodents were treated with either systemic or direct PVN Ex-4 followed by acyl ghrelin microinjection. While our results showed that both systemic and PVN administration of Ex-4 significantly reduced RER, importantly, Ex-4 pretreatment itself reliably inhibited the impact of ghrelin on RER. Overall, these findings provide increasingly compelling evidence that GLP-1 and ghrelin signaling interact in the neural control of metabolic function within the PVN.
Collapse
Affiliation(s)
- Shayan Abtahi
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, United States
| | - Erin Howell
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, United States
| | - Jack T Salvucci
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, United States
| | - Joshua M R Bastacky
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, United States
| | - David P Dunn
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, United States
| | - Paul J Currie
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, United States.
| |
Collapse
|
16
|
Wolak M, Staszewska T, Juszczak M, Gałdyszyńska M, Bojanowska E. Anti-inflammatory and pro-healing impacts of exendin-4 treatment in Zucker diabetic rats: Effects on skin wound fibroblasts. Eur J Pharmacol 2018; 842:262-269. [PMID: 30391742 DOI: 10.1016/j.ejphar.2018.10.053] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 10/30/2018] [Accepted: 10/31/2018] [Indexed: 02/07/2023]
Abstract
Using male Zucker diabetic fatty (ZDF) rats implanted subcutaneously with polyethylene mesh pieces stimulating granulation tissue development, we investigated the effects of the in vivo and in vitro treatment with exendin-4, a glucagon-like peptide-1 agonist displaying a variety of antidiabetic actions, on the markers of metabolism, inflammation, and healing in addition to skin wound fibroblast/myofibroblast activities. Exendin-4 at increasing doses of 3-10 μg/kg or 0.9% saline was injected daily to ZDF rats pre-implanted with the mesh for 3 weeks. Then, fibroblasts/myofibroblasts isolated from the granulation tissue in both groups were further exposed in vitro to exendin-4 at concentrations of 0-100 nmol/l. After a 3-week administration period, cumulative food and water intake and body weight were reduced significantly. The serum and fibroblast culture medium C-reactive protein (CRP) concentrations and matrix metalloprotease-9/tissue matrix metalloproteinase inhibitor-1 (MMP-9/TIMP-1) ratio in the fibroblast culture medium were diminished significantly in the exendin-4 pretreated group, indicating the increased expression of anti-inflammatory and pro-healing biomarkers. In vivo exendin-4 treatment also increased the number of living fibroblasts/myofibroblasts in cell cultures. The subsequent in vitro exposure to exendin-4 significantly increased metabolic activity and total collagen content in fibroblast/myofibroblast colonies derived from exendin-4-pretreated rats but reduced the number of viable cells. A cytotoxic effect was noted at the highest exendin-4 concentrations used. To conclude, the treatment of diabetic rats with exendin-4 had beneficial effects on systemic and tissue metabolic, inflammatory, and healing markers and on fibroblast functions crucial for wound repair but showed some cytotoxicity on these cells.
Collapse
Affiliation(s)
- Monika Wolak
- Department of Behavioral Pathophysiology, Medical University of Łódź, 60 Narutowicza Street, 90-136 Łódź, Poland
| | - Teresa Staszewska
- Department of Behavioral Pathophysiology, Medical University of Łódź, 60 Narutowicza Street, 90-136 Łódź, Poland
| | - Marlena Juszczak
- Department of Pathophysiology and Experimental Neuroendocrinology, Medical University of Łódź, 60 Narutowicza Street, 90-136 Łódź, Poland
| | - Małgorzata Gałdyszyńska
- Department of Neuropeptide Research, Medical University of Łódź, 60 Narutowicza Street, 90-136 Łódź, Poland
| | - Ewa Bojanowska
- Department of Behavioral Pathophysiology, Medical University of Łódź, 60 Narutowicza Street, 90-136 Łódź, Poland.
| |
Collapse
|
17
|
Lee SJ, Sanchez-Watts G, Krieger JP, Pignalosa A, Norell PN, Cortella A, Pettersen KG, Vrdoljak D, Hayes MR, Kanoski SE, Langhans W, Watts AG. Loss of dorsomedial hypothalamic GLP-1 signaling reduces BAT thermogenesis and increases adiposity. Mol Metab 2018; 11:33-46. [PMID: 29650350 PMCID: PMC6001878 DOI: 10.1016/j.molmet.2018.03.008] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/09/2018] [Accepted: 03/14/2018] [Indexed: 12/15/2022] Open
Abstract
Objective Glucagon-like peptide-1 (GLP-1) neurons in the hindbrain densely innervate the dorsomedial hypothalamus (DMH), a nucleus strongly implicated in body weight regulation and the sympathetic control of brown adipose tissue (BAT) thermogenesis. Therefore, DMH GLP-1 receptors (GLP-1R) are well placed to regulate energy balance by controlling sympathetic outflow and BAT function. Methods We investigate this possibility in adult male rats by using direct administration of GLP-1 (0.5 ug) into the DMH, knocking down DMH GLP-1R mRNA with viral-mediated RNA interference, and by examining the neurochemical phenotype of GLP-1R expressing cells in the DMH using in situ hybridization. Results GLP-1 administered into the DMH increased BAT thermogenesis and hepatic triglyceride (TG) mobilization. On the other hand, Glp1r knockdown (KD) in the DMH increased body weight gain and adiposity, with a concomitant reduction in energy expenditure (EE), BAT temperature, and uncoupling protein 1 (UCP1) expression. Moreover, DMH Glp1r KD induced hepatic steatosis, increased plasma TG, and elevated liver specific de-novo lipogenesis, effects that collectively contributed to insulin resistance. Interestingly, DMH Glp1r KD increased neuropeptide Y (NPY) mRNA expression in the DMH. GLP-1R mRNA in the DMH, however, was found in GABAergic not NPY neurons, consistent with a GLP-1R-dependent inhibition of NPY neurons that is mediated by local GABAergic neurons. Finally, DMH Glp1r KD attenuated the anorexigenic effects of the GLP-1R agonist exendin-4, highlighting an important role of DMH GLP-1R signaling in GLP-1-based therapies. Conclusions Collectively, our data show that DMH GLP-1R signaling plays a key role for BAT thermogenesis and adiposity. DMH GLP-1R stimulation acutely increases BAT thermogenesis. DMH GLP-1R mRNA knockdown decreases EE and BAT thermogenesis. DMH GLP-1R mRNA knockdown impairs lipid and glucose metabolism. Reduced DMH GLP-1R signaling blunts the anorexigenic responses to Ex-4. DMH GLP-1R signaling indirectly regulates NPY gene expression.
Collapse
Affiliation(s)
- Shin J Lee
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland.
| | - Graciela Sanchez-Watts
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | | | - Angelica Pignalosa
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland
| | - Puck N Norell
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland
| | - Alyssa Cortella
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Klaus G Pettersen
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland
| | - Dubravka Vrdoljak
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland
| | - Matthew R Hayes
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Scott E Kanoski
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Wolfgang Langhans
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland
| | - Alan G Watts
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| |
Collapse
|
18
|
Leigh SJ, Lee F, Morris MJ. Hyperpalatability and the Generation of Obesity: Roles of Environment, Stress Exposure and Individual Difference. Curr Obes Rep 2018; 7:6-18. [PMID: 29435959 DOI: 10.1007/s13679-018-0292-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
PURPOSE OF REVIEW This review investigates how exposure to palatable food and its associated cues alters appetite regulation and feeding behaviour to drive overeating and weight gain. RECENT FINDINGS Both supraphysiological and physiological feeding systems are affected by exposure to palatable foods and its associated cues. Preclinical research, largely using rodents, has demonstrated that palatable food modulates feeding-related neural systems and food-seeking behaviour by recruiting the mesolimbic reward pathway. This is supported by studies in adolescents which have shown that mesolimbic activity in response to palatable food cues and consumption predicts future weight gain. Additionally, stress exposure, environmental factors and individual susceptibility have been shown to modulate the effects of highly palatable foods on behaviour. Further preclinical research using free-choice diets modelling the modern obesogenic environment is needed to identify how palatable foods drive overeating. Moreover, future clinical research would benefit from more appropriate quantification of palatability, making use of rating systems and surveys.
Collapse
Affiliation(s)
- Sarah-Jane Leigh
- Department of Pharmacology, School of Medical Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Frances Lee
- Department of Pharmacology, School of Medical Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Margaret J Morris
- Department of Pharmacology, School of Medical Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia.
| |
Collapse
|
19
|
Patel V, Joharapurkar A, Kshirsagar S, Patel M, Sutariya B, Patel H, Pandey D, Patel D, Ranvir R, Kadam S, Bahekar R, Jain M. Coagonist of glucagon-like peptide-1 and glucagon receptors ameliorates nonalcoholic fatty liver disease. Can J Physiol Pharmacol 2018; 96:587-596. [PMID: 29406832 DOI: 10.1139/cjpp-2017-0683] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is often associated with obesity and type 2 diabetes. Coagonists of glucagon-like peptide-1 receptor (GLP-1R) and glucagon receptor (GCGR) are under clinical investigation for the treatment of obesity and type 2 diabetes. In this study, we have demonstrated the effect of a balanced coagonist in the treatment of NAFLD using mouse models. GLP-1R agonist exendin-4, glucagon, and coagonist (Aib2 C24 chimera2) were administered to C57BL6/J mice, in which NAFLD was induced by carbon tetrachloride (CCl4) treatment after high-fat diet (HFD) feeding, and choline-deficient, L-amino-acid-defined HFD (CDAHFD) feeding. Repeated dose administration of coagonist significantly attenuated liver inflammation and steatosis induced by acute and long-term treatment with CCl4 in HFD-fed mice. Coagonist markedly attenuated the CDAHFD-induced expression of TIMP-1, MMP-9, TNF-α, MCP-1, COL1A1, and α-SMA. It also inhibited progression of hepatic steatosis and fibrosis in mice. Exendin-4 was better than glucagon, but coagonist was most effective in reduction of hepatic inflammation as well as steatosis. Coagonist of GLP-1R and GCGR improved NAFLD in C57BL6/J mice. This effect is mediated by reduction in lipotoxicity and inflammation in liver.
Collapse
Affiliation(s)
- Vishal Patel
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| | - Amit Joharapurkar
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| | - Samadhan Kshirsagar
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| | - Maulik Patel
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| | - Brijesh Sutariya
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| | - Hiren Patel
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| | - Dheerendra Pandey
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| | - Dipam Patel
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| | - Ramchandra Ranvir
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| | - Shekhar Kadam
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| | - Rajesh Bahekar
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| | - Mukul Jain
- Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India.,Zydus Research Centre, Cadila Healthcare Limited, Sarkhej-Bavla N.H. No. 8A, Moraiya, Ahmedabad, 382210, India
| |
Collapse
|
20
|
Exendin-4 reduces food intake via the PI3K/AKT signaling pathway in the hypothalamus. Sci Rep 2017; 7:6936. [PMID: 28761132 PMCID: PMC5537284 DOI: 10.1038/s41598-017-06951-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 06/19/2017] [Indexed: 01/04/2023] Open
Abstract
Exendin-4 (EX-4), a glucagon-like peptide-1 (GLP-1) receptor agonist, has been shown to reduce food intake and to increase proopiomelanocortin (POMC) gene expression in the hypothalamus. In this study, we examined the potential neural mechanisms by which these effects occur. Male Sprague Dawley rats were implanted with a cannula in the third ventricle of the brain through which an inhibitor of phosphatidylinositol-3 kinase (PI3K) (wortmannin) was administered, and EX-4 or vehicle was administered via intraperitoneal (IP) injection. The activity of PI3K/protein kinase B (AKT) and insulin receptor substrate-1 (IRS-1) in the hypothalamic arcuate was determined. We found that EX-4 treatment significantly decreased food intake and body weight. However, there were almost no changes in food intake and body weight when wortmannin injection (into the third ventricle) occurred prior to EX-4 IP injection. EX-4 not only increased the activity of PI3K/AKT, but it also increased IRS-1 activity. These results show that EX-4 likely suppresses food intake due to its ability to enhance insulin signaling.
Collapse
|
21
|
Bojanowska E, Ciosek J. Can We Selectively Reduce Appetite for Energy-Dense Foods? An Overview of Pharmacological Strategies for Modification of Food Preference Behavior. Curr Neuropharmacol 2016; 14:118-42. [PMID: 26549651 PMCID: PMC4825944 DOI: 10.2174/1570159x14666151109103147] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 09/19/2015] [Accepted: 10/31/2015] [Indexed: 12/11/2022] Open
Abstract
Excessive intake of food, especially palatable and energy-dense carbohydrates and fats, is
largely responsible for the growing incidence of obesity worldwide. Although there are a number of
candidate antiobesity drugs, only a few of them have been proven able to inhibit appetite for palatable
foods without the concurrent reduction in regular food consumption. In this review, we discuss the
interrelationships between homeostatic and hedonic food intake control mechanisms in promoting
overeating with palatable foods and assess the potential usefulness of systemically administered pharmaceuticals that
impinge on the endogenous cannabinoid, opioid, aminergic, cholinergic, and peptidergic systems in the modification of
food preference behavior. Also, certain dietary supplements with the potency to reduce specifically palatable food intake
are presented. Based on human and animal studies, we indicate the most promising therapies and agents that influence the
effectiveness of appetite-modifying drugs. It should be stressed, however, that most of the data included in our review
come from preclinical studies; therefore, further investigations aimed at confirming the effectiveness and safety of the
aforementioned medications in the treatment of obese humans are necessary.
Collapse
Affiliation(s)
- Ewa Bojanowska
- Department of Behavioral Pathophysiology, Institute of General and Experimental Pathology, Medical University of Lodz, 60 Narutowicza Street, 90-136 Lodz, Poland.
| | | |
Collapse
|
22
|
Bodnaruc AM, Prud’homme D, Blanchet R, Giroux I. Nutritional modulation of endogenous glucagon-like peptide-1 secretion: a review. Nutr Metab (Lond) 2016; 13:92. [PMID: 27990172 PMCID: PMC5148911 DOI: 10.1186/s12986-016-0153-3] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 11/30/2016] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The positive influences of glucagon-like peptide-1 (GLP-1) on blood glucose homeostasis, appetite sensations, and food intake provide a strong rationale for its therapeutic potential in the nutritional management of obesity and type 2 diabetes. AIM To summarize GLP-1 physiology and the nutritional modulation of its secretion in the context of obesity and type 2 diabetes management. FINDINGS GLP-1 is mainly synthesized and secreted by enteroendocrine L-cells of the gastrointestinal tract. Its secretion is partly mediated by the direct nutrient sensing by G-protein coupled receptors which specifically bind to monosaccharides, peptides and amino-acids, monounsaturated and polyunsaturated fatty acids as well as to short chain fatty acids. Foods rich in these nutrients, such as high-fiber grain products, nuts, avocados and eggs also seem to influence GLP-1 secretion and may thus promote associated beneficial outcomes in healthy individuals as well as individuals with type 2 diabetes or with other metabolic disturbances. CONCLUSION The stimulation of endogenous GLP-1 secretion by manipulating the composition of the diet may be a relevant strategy for obesity and type 2 diabetes management. A better understanding of the dose-dependent effects as well as the synergistic effects of nutrients and whole foods is needed in order to develop recommendations to appropriately modify the diet to enhance GLP-1 beneficial effects.
Collapse
Affiliation(s)
- Alexandra M. Bodnaruc
- School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, 35, University Private, Room 050F, K1N 6N5 Ottawa, ON Canada
- Institut de Recherche de l’Hôpital Montfort, Institut du savoir, 745 Montreal Road, Room 202, K1K 0T2 Ottawa, ON Canada
- School of Nutrition Sciences, Faculty of Health Sciences, University of Ottawa, 35 University Private, Room 050F, K1N 6N5 Ottawa, ON Canada
| | - Denis Prud’homme
- School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, 35, University Private, Room 050F, K1N 6N5 Ottawa, ON Canada
- Institut de Recherche de l’Hôpital Montfort, Institut du savoir, 745 Montreal Road, Room 202, K1K 0T2 Ottawa, ON Canada
| | - Rosanne Blanchet
- School of Nutrition Sciences, Faculty of Health Sciences, University of Ottawa, 35 University Private, Room 050F, K1N 6N5 Ottawa, ON Canada
| | - Isabelle Giroux
- Institut de Recherche de l’Hôpital Montfort, Institut du savoir, 745 Montreal Road, Room 202, K1K 0T2 Ottawa, ON Canada
- School of Nutrition Sciences, Faculty of Health Sciences, University of Ottawa, 25 University Private, Room 116, K1N 6N5 Ottawa, ON Canada
| |
Collapse
|
23
|
The glucagon-like peptide-1 analog exendin-4 antagonizes the effect of acyl ghrelin on the respiratory exchange ratio. Neuroreport 2016; 27:992-6. [DOI: 10.1097/wnr.0000000000000650] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
24
|
de La Serre CB, Kim YJ, Moran TH, Bi S. Dorsomedial hypothalamic NPY affects cholecystokinin-induced satiety via modulation of brain stem catecholamine neuronal signaling. Am J Physiol Regul Integr Comp Physiol 2016; 311:R930-R939. [PMID: 27534875 DOI: 10.1152/ajpregu.00184.2015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 08/16/2016] [Indexed: 12/31/2022]
Abstract
Increased neuropeptide Y (NPY) gene expression in the dorsomedial hypothalamus (DMH) has been shown to cause hyperphagia, but the pathway underlying this effect remains less clear. Hypothalamic neural systems play a key role in the control of food intake, in part, by modulating the effects of meal-related signals, such as cholecystokinin (CCK). An increase in DMH NPY gene expression decreases CCK-induced satiety. Since activation of catecholaminergic neurons within the nucleus of solitary tract (NTS) contributes to the feeding effects of CCK, we hypothesized that DMH NPY modulates NTS neural catecholaminergic signaling to affect food intake. We used an adeno-associated virus system to manipulate DMH NPY gene expression in rats to examine this pathway. Viral-mediated hrGFP anterograde tracing revealed that DMH NPY neurons project to the NTS; the projections were in close proximity to catecholaminergic neurons, and some contained NPY. Viral-mediated DMH NPY overexpression resulted in an increase in NPY content in the NTS, a decrease in NTS tyrosine hydroxylase (TH) expression, and reduced exogenous CCK-induced satiety. Knockdown of DMH NPY produced the opposite effects. Direct NPY administration into the fourth ventricle of intact rats limited CCK-induced satiety and overall TH phosphorylation. Taken together, these results demonstrate that DMH NPY descending signals affect CCK-induced satiety, at least in part, via modulation of NTS catecholaminergic neuronal signaling.
Collapse
Affiliation(s)
| | - Yonwook J Kim
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Timothy H Moran
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Sheng Bi
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| |
Collapse
|
25
|
Lee SJ, Diener K, Kaufman S, Krieger JP, Pettersen KG, Jejelava N, Arnold M, Watts AG, Langhans W. Limiting glucocorticoid secretion increases the anorexigenic property of Exendin-4. Mol Metab 2016; 5:552-565. [PMID: 27408779 PMCID: PMC4921942 DOI: 10.1016/j.molmet.2016.04.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 04/14/2016] [Accepted: 04/27/2016] [Indexed: 12/25/2022] Open
Abstract
Objective Glucagon-like peptide-1 (GLP-1) analogs are attractive options for the treatment of type II diabetes and obesity because of their incretin and anorexigenic effects. Peripheral administration of the GLP-1R agonist Exendin-4 (Ex-4) also increases glucocorticoid secretion in rodents and humans, but whether the released glucocorticoids interact with Ex-4's anorexigenic effect remains unclear. Methods To test this, we used two experimental approaches that suppress corticosterone secretion and then assessed Ex-4 effects on eating in adult male rats. First, we combined acute and chronic low dose dexamethasone treatment with Ex-4. Second, we ablated hindbrain catecholamine neurons projecting to the hypothalamus with anti-dopamine-β-hydroxylase-saporin (DSAP) to block Ex-4-induced corticosterone secretion. Results Combining dexamethasone and Ex-4 produced a larger acute anorexigenic effect than Ex-4 alone. Likewise, chronic dexamethasone and Ex-4 co-treatment produced a synergistic effect on eating and greater body weight loss in diet-induced obese rats than Ex-4 alone. DSAP lesions not only blunted Ex-4's ability to increase corticosterone secretion, but potentiated the anorexigenic effect of Ex-4, indicating that Ex-4-dependent corticosterone secretion opposes Ex-4's actions. Consistent with the enhancement of Ex-4's anorexigenic effect, DSAP lesion altered Ex-4-dependent changes in neuropeptide Y, preproglucagon, and corticotropin releasing hormone gene expression involved in glucocorticoid feedback. Conclusions Our findings demonstrate that limiting glucocorticoid secretion and actions with low dose dexamethasone or DSAP lesion increases Ex-4's ability to reduce food intake and body weight. Novel glucocorticoid receptor based mechanisms, therefore, may help enhance GLP-1-based obesity therapies. Blocking HPA axis by low dose dexamethasone increased the anorexigenic property of Ex-4. Dexamethasone/Ex-4 co-treatment reduced food intake and body weight in diet-induced obese rats more than Ex-4 alone. A brain lesion model identified a potential central interaction between glucocorticoids and GLP-1 in food intake control.
Collapse
Affiliation(s)
- Shin J Lee
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland.
| | - Katharina Diener
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland
| | - Sharon Kaufman
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland
| | | | - Klaus G Pettersen
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland
| | - Nino Jejelava
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland
| | - Myrtha Arnold
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland
| | - Alan G Watts
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Wolfgang Langhans
- Physiology and Behavior Laboratory, ETH Zürich, 8603 Schwerzenbach, Switzerland
| |
Collapse
|
26
|
Anderberg RH, Richard JE, Hansson C, Nissbrandt H, Bergquist F, Skibicka KP. GLP-1 is both anxiogenic and antidepressant; divergent effects of acute and chronic GLP-1 on emotionality. Psychoneuroendocrinology 2016; 65:54-66. [PMID: 26724568 DOI: 10.1016/j.psyneuen.2015.11.021] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 10/31/2015] [Accepted: 11/20/2015] [Indexed: 01/04/2023]
Abstract
Glucagon-like peptide 1 (GLP-1), produced in the intestine and hindbrain, is known for its glucoregulatory and appetite suppressing effects. GLP-1 agonists are in clinical use for treatment of type 2 diabetes and obesity. GLP-1, however, may also affect brain areas associated with emotionality regulation. Here we aimed to characterize acute and chronic impact of GLP-1 on anxiety and depression-like behavior. Rats were subjected to anxiety and depression behavior tests following acute or chronic intracerebroventricular or intra-dorsal raphe (DR) application of GLP-1 receptor agonists. Serotonin or serotonin-related genes were also measured in the amygdala, DR and the hippocampus. We demonstrate that both GLP-1 and its long lasting analog, Exendin-4, induce anxiety-like behavior in three rodent tests of this behavior: black and white box, elevated plus maze and open field test when acutely administered intraperitoneally, into the lateral ventricle, or directly into the DR. Acute central GLP-1 receptor stimulation also altered serotonin signaling in the amygdala. In contrast, chronic central administration of Exendin-4 did not alter anxiety-like behavior but significantly reduced depression-like behavior in the forced swim test. Importantly, this positive effect of Exendin-4 was not due to significant body weight loss and reduced food intake, since rats pair-fed to Exendin-4 rats did not show altered mood. Collectively we show a striking impact of central GLP-1 on emotionality and the amygdala serotonin signaling that is divergent under acute versus chronic GLP-1 activation conditions. We also find a novel role for the DR GLP-1 receptors in regulation of behavior. These results may have direct relevance to the clinic, and indicate that Exendin-4 may be especially useful for obese patients manifesting with comorbid depression.
Collapse
Affiliation(s)
- Rozita H Anderberg
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Sweden
| | - Jennifer E Richard
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Sweden
| | - Caroline Hansson
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Sweden
| | - Hans Nissbrandt
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Sweden
| | - Filip Bergquist
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Sweden
| | - Karolina P Skibicka
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Sweden.
| |
Collapse
|
27
|
Barreto-Vianna ARC, Aguila MB, Mandarim-de-Lacerda CA. Effects of liraglutide in hypothalamic arcuate nucleus of obese mice. Obesity (Silver Spring) 2016; 24:626-33. [PMID: 26916241 DOI: 10.1002/oby.21387] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 10/06/2015] [Accepted: 10/06/2015] [Indexed: 12/31/2022]
Abstract
OBJECTIVE The neuroprotective effects of liraglutide (200 μg/kg, twice daily, subcutaneous administration) in the hypothalamic arcuate nucleus (ARC) of diet-induced obese mice were investigated. METHODS C57BL/6 mice were separated into groups: standard chow treated with vehicle or liraglutide and the respective liraglutide pair-fed group; high-fat diet treated with vehicle or liraglutide and the respective pair-fed group. Body mass (BM) evolution, carbohydrate metabolism, leptin resistance, proteins involved in energetic balance, apoptosis, and microglia in the ARC were studied. RESULTS Obese animals showed glucose intolerance, resistance to insulin and to anorexigenic effect of leptin, and microgliosis accompanied by elevated Bax/Bcl2 ratio in the ARC. Liraglutide improved the carbohydrate metabolism, BM loss, and the activation of pro-opiomelanocortin (POMC) and cocaine and amphetamine-regulated transcript (CART) in the ARC. The liraglutide enhanced leptin sensitivity and diminished the microgliosis with decrease in Bax/Bcl2 ratio. CONCLUSIONS Liraglutide activates central anorexigenic pathways, thereby diminishing the energy intake of obese mice and improving the metabolic parameters related to obesity. Liraglutide is a relevant neuroprotective agent, which can decrease the microgliosis and stimulate the anti-apoptotic pathway, a significant effect in the treatment of obesity and its comorbidities. Some benefits of liraglutide are independent of the BM loss, which usually accompanies the drug administration.
Collapse
Affiliation(s)
- Andre R C Barreto-Vianna
- Laboratory of Morphometry, Metabolism, and Cardiovascular Disease, Biomedical Center, Institute of Biology, State University of Rio De Janeiro, Rio De Janeiro, Brazil
| | - Marcia B Aguila
- Laboratory of Morphometry, Metabolism, and Cardiovascular Disease, Biomedical Center, Institute of Biology, State University of Rio De Janeiro, Rio De Janeiro, Brazil
| | - Carlos A Mandarim-de-Lacerda
- Laboratory of Morphometry, Metabolism, and Cardiovascular Disease, Biomedical Center, Institute of Biology, State University of Rio De Janeiro, Rio De Janeiro, Brazil
| |
Collapse
|
28
|
Bauer PV, Hamr SC, Duca FA. Regulation of energy balance by a gut-brain axis and involvement of the gut microbiota. Cell Mol Life Sci 2016; 73:737-55. [PMID: 26542800 PMCID: PMC11108299 DOI: 10.1007/s00018-015-2083-z] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 10/22/2015] [Accepted: 10/26/2015] [Indexed: 12/11/2022]
Abstract
Despite significant progress in understanding the homeostatic regulation of energy balance, successful therapeutic options for curbing obesity remain elusive. One potential target for the treatment of obesity is via manipulation of the gut-brain axis, a complex bidirectional communication system that is crucial in maintaining energy homeostasis. Indeed, ingested nutrients induce secretion of gut peptides that act either via paracrine signaling through vagal and non-vagal neuronal relays, or in an endocrine fashion via entry into circulation, to ultimately signal to the central nervous system where appropriate responses are generated. We review here the current hypotheses of nutrient sensing mechanisms of enteroendocrine cells, including the release of gut peptides, mainly cholecystokinin, glucagon-like peptide-1, and peptide YY, and subsequent gut-to-brain signaling pathways promoting a reduction of food intake and an increase in energy expenditure. Furthermore, this review highlights recent research suggesting this energy regulating gut-brain axis can be influenced by gut microbiota, potentially contributing to the development of obesity.
Collapse
Affiliation(s)
- Paige V Bauer
- Department of Medicine, Toronto General Research Institute, UHN, Toronto, ON, M5G 1L7, Canada
- Department of Physiology, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Sophie C Hamr
- Department of Medicine, Toronto General Research Institute, UHN, Toronto, ON, M5G 1L7, Canada
- Department of Physiology, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Frank A Duca
- Department of Medicine, Toronto General Research Institute, UHN, Toronto, ON, M5G 1L7, Canada.
- MaRS Centre, Toronto Medical Discovery Tower, Room 10-701H, 101 College Street, Toronto, ON, M5G 1L7, Canada.
| |
Collapse
|
29
|
Bernosky-Smith KA, Stanger DB, Trujillo AJ, Mitchell LR, España RA, Bass CE. The GLP-1 agonist exendin-4 attenuates self-administration of sweetened fat on fixed and progressive ratio schedules of reinforcement in rats. Pharmacol Biochem Behav 2015; 142:48-55. [PMID: 26701752 DOI: 10.1016/j.pbb.2015.12.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 11/21/2015] [Accepted: 12/14/2015] [Indexed: 01/15/2023]
Abstract
GLP-1 agonists such as exendin-4 (EX4) are used in the treatment of type-2 diabetes and have the additional benefit of promoting weight loss. GLP-1 agonists decrease feeding through peripheral effects, but recent evidence suggests they may also influence sweet or high fat preference, as well as motivation to obtain these tastants. Yet it remains unclear how GLP-1-induced alterations in food preference influences decreases in overall feeding. The current study sought to determine if EX4 affects the reinforcing strength and consumption of a highly palatable sweet/fat reinforcer. Rats were trained to self-administer sweetened vegetable shortening (SVS) under fixed (FR) and progressive ratio (PR) schedules of reinforcement. EX4 (0.3-2.4μg/kg, i.p.) administered one hour prior to operant sessions significantly reduced responses for SVS under both FR and PR schedules, although the lowest active dose (0.6μg/kg) significantly suppressed FR responding only. EX4 also dose dependently decreased locomotor activity (0.6-2.4μg/kg doses), but did not enhance acute kaolin intake, suggesting that nausea did not influence the self-administration results. Analysis of ED50 values show that EX4 is more effective at inhibiting FR responding versus PR, indicating that EX4 may have more potent effects on amount consumed versus motivation for SVS. Although EX4 caused generalized locomotor suppression, these results do not fully explain the decreases in operant responding. For example, a dose of EX4 (0.6μg/kg) that significantly suppressed locomotor activity did not affect the mean total number of lever presses during PR sessions (59±15), although it did significantly reduce lever presses during FR sessions (21±3). In addition, the pattern of intake was constant at the beginning of the sessions in both PR and FR schedules, regardless of the dose. Together these data suggest that EX4 inhibits consumption of a palatable high sweet/high fat reinforcer potentially through altering satiety.
Collapse
Affiliation(s)
| | - David B Stanger
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo, 3435 Main St, Buffalo, NY, United States
| | - Alexandria J Trujillo
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo, 3435 Main St, Buffalo, NY, United States
| | - Luke R Mitchell
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Rodrigo A España
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Caroline E Bass
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo, 3435 Main St, Buffalo, NY, United States.
| |
Collapse
|
30
|
Yang Y, Ma D, Xu W, Chen F, Du T, Yue W, Shao S, Yuan G. Exendin-4 reduces tau hyperphosphorylation in type 2 diabetic rats via increasing brain insulin level. Mol Cell Neurosci 2015; 70:68-75. [PMID: 26640240 DOI: 10.1016/j.mcn.2015.10.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 08/30/2015] [Accepted: 10/15/2015] [Indexed: 12/19/2022] Open
Abstract
Type 2 diabetes (T2D) is a high risk factor for Alzheimer's disease (AD). Our previous study identified that hyperphosphorylation of tau protein, which is one of the pathophysiologic hallmarks of AD, also occurred in T2D rats' brain; while glucagon-like peptide-1 (GLP-1) mimetics, a type of drug used in T2D, could decrease the phosphorylation of tau, probably via augmenting insulin signaling pathway. The purpose of this study was to further explore the mechanisms that underlie the effect of exendin-4 (ex-4, a GLP-1 receptor agonist) in reducing tau phosphorylation. We found that peripheral ex-4 injection in T2D rats reduced hyperphosphorylation of tau protein in rat hippocampus, probably via increasing hippocampal insulin which activated insulin signaling. Furthermore, we found that ex-4 could neither activate insulin signaling, nor reduce tau phosphorylation in HT22 neuronal cells in the absence of insulin. These results suggested that insulin is required in reduction of tau hyperphosphorylation by ex-4 in brain rats with T2D.
Collapse
Affiliation(s)
- Yan Yang
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030. PR China
| | - Delin Ma
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030. PR China
| | - Weijie Xu
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030. PR China
| | - Fuqiong Chen
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030. PR China
| | - Tingting Du
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030. PR China
| | - Wenzhu Yue
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030. PR China
| | - Shiying Shao
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030. PR China.
| | - Gang Yuan
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030. PR China.
| |
Collapse
|
31
|
Price SL, Minnion JS, Bloom SR. Increased food intake with oxyntomodulin analogues. Peptides 2015; 73:95-100. [PMID: 26431789 PMCID: PMC4645461 DOI: 10.1016/j.peptides.2015.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 08/07/2015] [Accepted: 09/14/2015] [Indexed: 01/02/2023]
Abstract
Oxyntomodulin analogues offer a novel treatment for obesity. However during analogue screening in a rat model increased food intake was consistently observed. To further investigate this finding, a series of representative analogues (OXM14 and OXM15) and their Glu-3 equivalents (OXM14E3 and OXM15E3) were administered to rats for 7 days and food intake and bodyweight measurements taken. To investigate the role of glucagon receptor activation glutamate (Glu/E) was substituted at amino acid position 3. GLP-1 and glucagon receptor efficacy of the oxyntomodulin analogues and their Glu-3 counterparts were measured at the rat receptors in vitro. Doses of 25 nmol/kg of OXM14 and OXM15 increased food intake by up to 20%. Bodyweight was not significantly increased. Food intake was not increased with the Glu-3 peptides, indicating that a glucagon receptor mechanism may be responsible for the increase in food intake.
Collapse
Affiliation(s)
- Samantha L Price
- Department of Investigative Medicine, Imperial College, London W12 0NN, United Kingdom
| | - James S Minnion
- Department of Investigative Medicine, Imperial College, London W12 0NN, United Kingdom
| | - Stephen R Bloom
- Department of Investigative Medicine, Imperial College, London W12 0NN, United Kingdom.
| |
Collapse
|
32
|
Bodnar RJ. Endogenous opioids and feeding behavior: A decade of further progress (2004-2014). A Festschrift to Dr. Abba Kastin. Peptides 2015; 72:20-33. [PMID: 25843025 DOI: 10.1016/j.peptides.2015.03.019] [Citation(s) in RCA: 18] [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] [Received: 03/03/2015] [Revised: 03/23/2015] [Accepted: 03/25/2015] [Indexed: 12/13/2022]
Abstract
Functional elucidation of the endogenous opioid system temporally paralleled the creation and growth of the journal, Peptides, under the leadership of its founding editor, Dr. Abba Kastin. He was prescient in publishing annual and uninterrupted reviews on Endogenous Opiates and Behavior that served as a microcosm for the journal under his stewardship. This author published a 2004 review, "Endogenous opioids and feeding behavior: a thirty-year historical perspective", summarizing research in this field between 1974 and 2003. The present review "closes the circle" by reviewing the last 10 years (2004-2014) of research examining the role of endogenous opioids and feeding behavior. The review summarizes effects upon ingestive behavior following administration of opioid receptor agonists, in opioid receptor knockout animals, following administration of general opioid receptor antagonists, following administration of selective mu, delta, kappa and ORL-1 receptor antagonists, and evaluating opioid peptide and opioid receptor changes in different food intake models.
Collapse
Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Behavioral and Cognitive Neuroscience Doctoral Program Cluster, Queens College, City University of New York, Flushing, NY 11367, United States.
| |
Collapse
|