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Walton KLW. Approaches to teaching about mechanisms of obesity in undergraduate pathophysiology courses. ADVANCES IN PHYSIOLOGY EDUCATION 2024; 48:304-308. [PMID: 38452331 DOI: 10.1152/advan.00122.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 02/13/2024] [Accepted: 03/05/2024] [Indexed: 03/09/2024]
Abstract
Views of obesity as a consequence of "lack of willpower" or other behavioral choices, rather than a complex array of biological and other factors, are quite common among undergraduate students. Many undergraduates in prenursing or biology programs have little exposure to the physiology and pathophysiology of obesity, including learning about leptin and other hormones involved in appetite control. I developed materials for teaching about the pathophysiology of obesity in two different pathophysiology courses: one designed as a survey of pathophysiology topics for prenursing majors, and the other designed as an in-depth exploration of the molecular and cellular basis of selected diseases for upper-division biology majors. In the molecular basis of disease course, obesity is covered as part of a unit organized around metabolic syndrome. The discussion includes molecular and cellular mechanisms that link obesity to several other diseases, including type 2 diabetes and atherosclerosis. This article briefly describes the approaches I have taken for teaching obesity to two different undergraduate student populations and lists several resources that may be useful tools for teaching about obesity.NEW & NOTEWORTHY This article describes approaches for teaching obesity in an allied health major pathophysiology course, and, additionally, in an upper-division biology major course on the cellular and molecular basis of disease.
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Affiliation(s)
- Kristen L W Walton
- Department of Biology, Missouri Western State University, St. Joseph, Missouri, United States
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2
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Ranjbar S, Akinsiku O, Hefner M, Jafari F, Kudchadkar G, Zaroudi M, Nathan AN, Booe H, Dhurandhar NV. Management of obesities with a cause specific approach. Int J Obes (Lond) 2024:10.1038/s41366-024-01539-x. [PMID: 38769423 DOI: 10.1038/s41366-024-01539-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 05/03/2024] [Accepted: 05/09/2024] [Indexed: 05/22/2024]
Affiliation(s)
- S Ranjbar
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA
| | - O Akinsiku
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA
| | - M Hefner
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA
| | - F Jafari
- Department of Nutritional Sciences, Penn State University, University Park, PA, USA
| | - G Kudchadkar
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA
| | - M Zaroudi
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA
| | - A N Nathan
- Center for Community Health Impact, University of Texas Health Sciences Center at Houston, El Paso, TX, USA
| | - H Booe
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA.
| | - N V Dhurandhar
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA.
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Roizen J, Long C, Casella A, Nguyen M, Danahy L, Seiler C, Lei M, Mark J. High dose dietary vitamin D allocates surplus calories to muscle and growth instead of fat via modulation of myostatin and leptin signaling. RESEARCH SQUARE 2024:rs.3.rs-4202165. [PMID: 38766160 PMCID: PMC11100886 DOI: 10.21203/rs.3.rs-4202165/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Obesity occurs because the body stores surplus calories as fat rather than as muscle. Fat secretes a hormone, leptin, that modulates energy balance at the brain. Changes in fat mass are mirrored by changes in serum leptin. Elevated leptin prompts the brain to decrease appetite and increase energy expenditure. In obesity, however, impaired leptin sensitivity mutes these leptin-mediated changes. We have limited understanding of what controls leptin production by fat or leptin sensitivity in the brain. Muscle produces a hormone, myostatin, that plays a role in muscle analogous to the one that leptin plays in fat. Absent myostatin leads to increased muscle mass and strength. As with leptin, we also do not know what controls myostatin production or sensitivity. Although fat mass and muscle mass are closely linked, the interplay between leptin and myostatin remains obscure. Here we describe an interplay linked thru vitamin D. Conventionally, it is thought that vitamin D improves strength via trophic effects at the muscle. However, we find here that high dose dietary vitamin D allocates excess calories to muscle and linear growth instead of storage as fat. Vitamin D mediates this allocation by decreasing myostatin production and increasing leptin production and sensitivity. That is, high dose vitamin D improves integration of organismal energy balance. Obesity, aging and other chronic inflammatory diseases are associated with increased fat mass and decreased muscle mass and function (e.g. sarcopenia). Our work provides a physiologic framework for how high-dose vitamin D would increase allocation of calories to muscle instead of fat in these pathologies. Additionally, our work reveals a novel link between the myostatin and leptin signaling whereby myostatin conveys energy needs to modulate leptin effects on calorie allocation. This result provides evidence to update the conventional model of energy stores sensing to a new model of energy balance sensing. In our proposed model, integration of leptin and myostatin signaling allows control of body composition independent of weight. Furthermore, our work reveals how physiologic seasonal variation in vitamin D may be important in controlling season-specific metabolism and calorie allocation to fat in winter and muscle and growth in summer.
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Affiliation(s)
- Jeffrey Roizen
- Childrens Hosp Philadelphia, Div Endocrinol & Diabet, 34th & Civ Ctr Blvd, Philadelphia, PA 19104 USA
| | - Caela Long
- The Children's Hospital of Philadelphia and The University of Pennsylvania Perelman School of Medicine
| | - Alex Casella
- The Children's Hospital of Philadelphia and The University of Pennsylvania Perelman School of Medicine
| | - Michael Nguyen
- The Children's Hospital of Philadelphia and The University of Pennsylvania Perelman School of Medicine
| | - Lo Danahy
- The Children's Hospital of Philadelphia and The University of Pennsylvania Perelman School of Medicine
| | | | - Meizan Lei
- The Children's Hospital of Philadelphia and The University of Pennsylvania Perelman School of Medicine
| | - Julian Mark
- The Children's Hospital of Philadelphia and The University of Pennsylvania Perelman School of Medicine
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Pena-Leon V, Perez-Lois R, Villalon M, Prida E, Muñoz-Moreno D, Fernø J, Quiñones M, Al-Massadi O, Seoane LM. Novel mechanisms involved in leptin sensitization in obesity. Biochem Pharmacol 2024; 223:116129. [PMID: 38490517 DOI: 10.1016/j.bcp.2024.116129] [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: 11/16/2023] [Revised: 01/21/2024] [Accepted: 03/12/2024] [Indexed: 03/17/2024]
Abstract
Leptin is a hormone that is secreted by adipocytes in proportion to adipose tissue size, and that informs the brain about the energy status of the body. Leptin acts through its receptor LepRb, expressed mainly in the hypothalamus, and induces a negative energy balance by potent inhibition of feeding and activation of energy expenditure. These actions have led to huge expectations for the development of therapeutic targets for metabolic complications based on leptin-derived compounds. However, the majority of patients with obesity presents elevated leptin production, suggesting that in this setting leptin is ineffective in the regulation of energy balance. This resistance to the action of leptin in obesity has led to the development of "leptin sensitizers," which have been tested in preclinical studies. Much research has focused on generating combined treatments that act on multiple levels of the gastrointestinal-brain axis. The gastrointestinal-brain axis secretes a variety of different anorexigenic signals, such as uroguanylin, glucagon-like peptide-1, amylin, or cholecystokinin, which can alleviate the resistance to leptin action. Moreover, alternative mechanism such as pharmacokinetics, proteostasis, the role of specific kinases, chaperones, ER stress and neonatal feeding modifications are also implicated in leptin resistance. This review will cover the current knowledge regarding the interaction of leptin with different endocrine factors from the gastrointestinal-brain axis and other novel mechanisms that improve leptin sensitivity in obesity.
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Affiliation(s)
- Veronica Pena-Leon
- Grupo Fisiopatología Endocrina, Departamento de Endocrinología, Instituto de Investigación Sanitaria de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS/SERGAS), Santiago de Compostela, Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Raquel Perez-Lois
- Grupo Fisiopatología Endocrina, Departamento de Endocrinología, Instituto de Investigación Sanitaria de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS/SERGAS), Santiago de Compostela, Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Maria Villalon
- Grupo Fisiopatología Endocrina, Departamento de Endocrinología, Instituto de Investigación Sanitaria de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS/SERGAS), Santiago de Compostela, Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Eva Prida
- Translational Endocrinology group, Endocrinology Section, Instituto de Investigación Sanitaria de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (IDIS/CHUS), Santiago de Compostela, Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Diego Muñoz-Moreno
- Translational Endocrinology group, Endocrinology Section, Instituto de Investigación Sanitaria de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (IDIS/CHUS), Santiago de Compostela, Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Johan Fernø
- Hormone Laboratory, Department of Biochemistry and Pharmacology, Haukeland University Hospital, 5201 Bergen, Norway
| | - Mar Quiñones
- Grupo Fisiopatología Endocrina, Departamento de Endocrinología, Instituto de Investigación Sanitaria de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS/SERGAS), Santiago de Compostela, Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain; CIBER de Fisiopatología de la Obesidad y la Nutrición, Instituto de Salud Carlos III, Madrid, Spain
| | - Omar Al-Massadi
- Translational Endocrinology group, Endocrinology Section, Instituto de Investigación Sanitaria de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (IDIS/CHUS), Santiago de Compostela, Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain; CIBER de Fisiopatología de la Obesidad y la Nutrición, Instituto de Salud Carlos III, Madrid, Spain.
| | - Luisa M Seoane
- Grupo Fisiopatología Endocrina, Departamento de Endocrinología, Instituto de Investigación Sanitaria de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS/SERGAS), Santiago de Compostela, Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain; CIBER de Fisiopatología de la Obesidad y la Nutrición, Instituto de Salud Carlos III, Madrid, Spain.
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Gutgesell RM, Nogueiras R, Tschöp MH, Müller TD. Dual and Triple Incretin-Based Co-agonists: Novel Therapeutics for Obesity and Diabetes. Diabetes Ther 2024; 15:1069-1084. [PMID: 38573467 PMCID: PMC11043266 DOI: 10.1007/s13300-024-01566-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 03/12/2024] [Indexed: 04/05/2024] Open
Abstract
The discovery of long-acting incretin receptor agonists represents a major stride forward in tackling the dual epidemic of obesity and diabetes. Here we outline the evolution of incretin-based pharmacotherapy, from exendin-4 to the discovery of the multi-incretin hormone receptor agonists that look set to be our next step toward curing diabetes and obesity. We discuss the multiagonists currently in clinical trials and the improvement in efficacy each new generation of these drugs bring. The success of these agents in preclinical models and clinical trials suggests a promising future for multiagonists in the treatment of metabolic diseases, with the most recent glucose-dependent insulinotropic peptide receptor:glucagon-like peptide 1 receptor:glucagon receptor (GIPR:GLP-1R:GCGR) triagonists rivaling the efficacy of bariatric surgery. However, further research is needed to fully understand how these therapies exert their effect on body weight and in the last section we cover open questions about the potential mechanisms of multiagonist drugs, and the understanding of how gut-brain communication can be leveraged to achieve sustained body weight loss without adverse effects.
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Affiliation(s)
- Robert M Gutgesell
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Munich, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Rubén Nogueiras
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), ISCIII, Madrid, Spain
- Department of Physiology, CiMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
| | - Matthias H Tschöp
- Helmholtz Munich, Neuherberg, Germany
- Division of Metabolic Diseases, Department of Medicine, Technical University of Munich, Munich, Germany
| | - Timo D Müller
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Munich, Neuherberg, Germany.
- German Center for Diabetes Research (DZD), Neuherberg, Germany.
- Walther-Straub Institute for Pharmacology and Toxicology, Ludwig-Maximilians University, Munich, Germany.
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Fansa S, Acosta A. The melanocortin-4 receptor pathway and the emergence of precision medicine in obesity management. Diabetes Obes Metab 2024; 26 Suppl 2:46-63. [PMID: 38504134 DOI: 10.1111/dom.15555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 02/15/2024] [Accepted: 02/29/2024] [Indexed: 03/21/2024]
Abstract
Over the past few decades, there has been a global surge in the prevalence of obesity, rendering it a globally recognized epidemic. Contrary to simply being a medical condition, obesity is an intricate disease with a multifactorial aetiology. Understanding the precise cause of obesity remains a challenge; nevertheless, there seems to be a complex interplay among biological, psychosocial and behavioural factors. Studies on the genetic factors of obesity have revealed several pathways in the brain that play a crucial role in food intake regulation. The best characterized pathway, thus far, is the leptin-melanocortin pathway, from which disruptions are responsible for the majority of monogenic obesity disorders. The effectiveness of conservative lifestyle interventions in addressing monogenic obesity has been limited. Therefore, it is crucial to complement the management strategy with pharmacological and surgical options. Emphasis has been placed on developing drugs aimed at replacing the absent signals, with the goal of restoring the pathway. In both monogenic and polygenic forms of obesity, outcomes differ across various interventions, likely due to the multifaceted nature of the disease. This underscores the need to explore alternative therapeutic strategies that can mitigate this heterogeneity. Precision medicine can be regarded as a powerful tool that can address this concern, as it values the understanding of the underlying abnormality triggering the disease and provides a tailored treatment accordingly. This would assist in optimizing outcomes of the current therapeutic approaches and even aid in the development of novel treatments capable of more effectively managing the global obesity epidemic.
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Affiliation(s)
- Sima Fansa
- Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Andres Acosta
- Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA
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7
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Chen M, Chen Y, Li C. Serum iron concentration and leptin inversely relate, partially mediated by body mass index in American adults. Nutr Res 2024; 124:1-12. [PMID: 38342069 DOI: 10.1016/j.nutres.2024.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 01/19/2024] [Accepted: 01/19/2024] [Indexed: 02/13/2024]
Abstract
Iron metabolism and leptin are interconnected, and both link with obesity. In this cross-sectional study, we hypothesized that serum iron markers associate with leptin, with body mass index (BMI) acting as a mediator, confounder, and effect modifier in this relationship. We analyzed data from the National Health and Nutrition Examination Survey III, with a focus on serum iron markers and leptin. The relationship between serum iron markers and leptin was determined by multiple linear regression. The bootstrap method was used to investigate the mediating effect of BMI on this association. Among 3888 American adults, serum iron and transferrin saturation showed a negative association with leptin (log2-transformed) (β: -0.010, 95% confidence interval [CI], -0.013 to -0.006, P < .001; β: -0.006, 95% CI, -0.008 to -0.004, P < .001). Total iron-binding capacity was positively associated with the serum concentration of leptin (log2-transformed) (β: 0.002, 95% CI, 0-0.004, P = .0292). Sex, BMI, and body fat percentage significantly influenced these associations. Notably, the association between the iron markers and leptin diminished in individuals with a BMI ≥30 kg/m2. There was no observable relationship between leptin and serum ferritin concentrations. BMI mediated 4.81% of the serum iron-leptin association, with no mediation of body fat percentage. Our study identified a link between serum iron and leptin, with BMI as a mediating factor. In clinical settings, it is vital to understand how treatments targeting iron metabolism can directly impact serum leptin concentration and the subsequent physiological changes.
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Affiliation(s)
- Mi Chen
- Division of Cardiac Rehabilitation, Department of Physical Medicine and Rehabilitation, Xiangya Hospital of Central South University, Changsha, Hunan, People's Republic of China; Department of Physical Medicine and Rehabilitation, The First Affiliated Hospital, Xinjiang Medical University, Urumqi, Xinjiang, People's Republic of China
| | - Yuebai Chen
- Faculty of Science, McGill University, Montreal, Quebec, Canada
| | - Chao Li
- Department of Respiration, The First Affiliated Hospital, Xinjiang Medical University, Urumqi, Xinjiang, People's Republic of China.
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LA Padula D, Zavaglia L, Hamad T, Nocito MC, Aquila S, Avena P, Rago V. Leptin effects: focusing on the relationship between obesity and male infertility. Minerva Endocrinol (Torino) 2024; 49:100-110. [PMID: 36251021 DOI: 10.23736/s2724-6507.22.03901-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The human male infertility has several causes interconnected to improper lifestyles such as smoking, sedentarism, environmental factors, toxins accumulation and energy imbalances. All these factors contribute to the obesity accompanied metabolic syndrome and hormonal alterations in the leptin-ghrelin axis. The leptin (Lep) has many pleiotropic effects in several biological systems, directly on the peripheral tissues or through the central nervous system. Many studies suggest that Lep is a key player in gonadal functions beside its documented role in reproductive regulation; however, further investigations are still necessary to elucidate all the molecular pathways involved in these mechanisms. Keeping into account that increased Lep levels in obese men are positively correlated with altered sperm parameters and testicular oxidative stress, evidence refers to Lep as a potential link between obesity and male infertility. This review represents an updated version on the concept of the Lep roles in mediating the male reproductive functions in obese patients.
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Affiliation(s)
- Davide LA Padula
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - Lucia Zavaglia
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - Tarig Hamad
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - Marta C Nocito
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - Saveria Aquila
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - Paola Avena
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - Vittoria Rago
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Cosenza, Italy -
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Guo X, Asthana P, Zhai L, Cheng KW, Gurung S, Huang J, Wu J, Zhang Y, Mahato AK, Saarma M, Ustav M, Kwan HY, Lyu A, Chan KM, Xu P, Bian ZX, Wong HLX. Artesunate treats obesity in male mice and non-human primates through GDF15/GFRAL signalling axis. Nat Commun 2024; 15:1034. [PMID: 38310105 PMCID: PMC10838268 DOI: 10.1038/s41467-024-45452-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 01/23/2024] [Indexed: 02/05/2024] Open
Abstract
Obesity, a global health challenge, is a major risk factor for multiple life-threatening diseases, including diabetes, fatty liver, and cancer. There is an ongoing need to identify safe and tolerable therapeutics for obesity management. Herein, we show that treatment with artesunate, an artemisinin derivative approved by the FDA for the treatment of severe malaria, effectively reduces body weight and improves metabolic profiles in preclinical models of obesity, including male mice with overnutrition-induced obesity and male cynomolgus macaques with spontaneous obesity, without inducing nausea and malaise. Artesunate promotes weight loss and reduces food intake in obese mice and cynomolgus macaques by increasing circulating levels of Growth Differentiation Factor 15 (GDF15), an appetite-regulating hormone with a brainstem-restricted receptor, the GDNF family receptor α-like (GFRAL). Mechanistically, artesunate induces the expression of GDF15 in multiple organs, especially the liver, in mice through a C/EBP homologous protein (CHOP)-directed integrated stress response. Inhibition of GDF15/GFRAL signalling by genetic ablation of GFRAL or tissue-specific knockdown of GDF15 abrogates the anti-obesity effect of artesunate in mice with diet-induced obesity, suggesting that artesunate controls bodyweight and appetite in a GDF15/GFRAL signalling-dependent manner. These data highlight the therapeutic benefits of artesunate in the treatment of obesity and related comorbidities.
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Affiliation(s)
- Xuanming Guo
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR, China
| | - Pallavi Asthana
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR, China.
| | - Lixiang Zhai
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR, China
| | - Ka Wing Cheng
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR, China
- Centre for Chinese Herbal Medicine Drug Development Limited, Hong Kong Baptist University, Hong Kong SAR, China
| | - Susma Gurung
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR, China
| | - Jiangang Huang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Jiayan Wu
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR, China
| | - Yijing Zhang
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR, China
| | - Arun Kumar Mahato
- Institute of Biotechnology-HILIFE, University of Helsinki, Helsinki, Finland
| | - Mart Saarma
- Institute of Biotechnology-HILIFE, University of Helsinki, Helsinki, Finland
| | | | - Hiu Yee Kwan
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR, China
| | - Aiping Lyu
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR, China
| | - Kui Ming Chan
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Pingyi Xu
- Department of Neurology, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Zhao-Xiang Bian
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR, China.
- Centre for Chinese Herbal Medicine Drug Development Limited, Hong Kong Baptist University, Hong Kong SAR, China.
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Sato S. Adipo-oncology: adipocyte-derived factors govern engraftment, survival, and progression of metastatic cancers. Cell Commun Signal 2024; 22:52. [PMID: 38238841 PMCID: PMC10797898 DOI: 10.1186/s12964-024-01474-4] [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] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 01/03/2024] [Indexed: 01/22/2024] Open
Abstract
Conventional therapies for metastatic cancers have limited efficacy. Recently, cancer therapies targeting noncancerous cells in tumor microenvironments have shown improved clinical outcomes in patients. However, further advances in our understanding of the metastatic tumor microenvironment are required to improve treatment outcomes. Adipocytes are distributed throughout the body, and as a part of the metastatic tumor microenvironment, they interact with cancer cells in almost all organs. Adipocytes secrete various factors that are reported to exert clinical effects on cancer progression, including engraftment, survival, and expansion at the metastatic sites. However, only a few studies have comprehensively examined their impact on cancer cells. In this review, we examined the impact of adipocytes on cancer by describing the adipocyte-secreted factors that are involved in controlling metastatic cancer, focusing on adipokines, such as adiponectin, leptin, visfatin, chemerin, resistin, apelin, and omentin. Adipocyte-secreted factors promote cancer metastasis and contribute to various biological functions of cancer cells, including migration, invasion, proliferation, immune evasion, and drug resistance at the metastatic sites. We propose the establishment and expansion of "adipo-oncology" as a research field to enhance the comprehensive understanding of the role of adipocytes in metastatic cancers and the development of more robust metastatic cancer treatments.
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Affiliation(s)
- Shinya Sato
- Morphological Analysis Laboratory, Kanagawa Cancer Center Research Institute, 2-3-2, Asahi-Ku, Yokohama, Kanagawa, 241-8515, Japan.
- Molecular Pathology and Genetics Division, Kanagawa Cancer Center Research Institute, 2-3-2, Asahi-Ku, Yokohama, Kanagawa, 241-8515, Japan.
- Department of Pathology, Kanagawa Cancer Center Hospital, 2-3-2, Asahi-Ku, Yokohama, Kanagawa, 241-8515, Japan.
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11
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Flier JS, Ahima RS. Leptin physiology and pathophysiology: knowns and unknowns 30 years after its discovery. J Clin Invest 2024; 134:e174595. [PMID: 38165042 PMCID: PMC10760948 DOI: 10.1172/jci174595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024] Open
Affiliation(s)
- Jeffrey S. Flier
- Department of Medicine and Neurobiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Rexford S. Ahima
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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12
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Yanik T, Durhan ST. Neuroendocrinological and Clinical Aspects of Leptin. Mini Rev Med Chem 2024; 24:886-894. [PMID: 37622709 DOI: 10.2174/1389557523666230825100154] [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: 12/18/2022] [Revised: 06/20/2023] [Accepted: 07/25/2023] [Indexed: 08/26/2023]
Abstract
Obesity is characterized by an abnormal increase in adipose tissue mass and is regarded as a neurobehavioral as well as a metabolic disorder. Increases in body fat are caused by even slight, long-term discrepancies between energy intake and energy expenditure. It is a chronic condition linked to the metabolic syndrome, a spectrum of risky conditions, such as diabetes, high blood pressure, and heart disease. With a swiftly rising prevalence, obesity has emerged as a significant global health concern. Leptin influences the brain's neuroendocrine and metabolic processes, which is important for maintaining energy homeostasis. White adipose tissue secretes the majority of leptin, and there is a positive correlation between leptin levels in the blood and body fat percentages. The central nervous system is also modulated by leptin levels to modify energy intake and usage. The idea of an obesity cure sparked excitement after it was discovered more than 25 years ago. However, the leptin medication only effectively reduces weight in patients with congenital leptin insufficiency and not in patients with typical obesity who may also have leptin resistance. Recent research has focused on the role of leptin in managing weight reduction and preventing "yo-yo dieting". This review concentrates on the neurological effects of leptin with a focus on therapeutic and diagnostic applications, particularly for childhood obesity.
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Affiliation(s)
- Tulin Yanik
- Department of Biological Sciences, Middle East Technical University, Ankara, 06800, Turkey
| | - Seyda Tugce Durhan
- Department of Biological Sciences, Middle East Technical University, Ankara, 06800, Turkey
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13
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Tucker JAL, Bornath DPD, McCarthy SF, Hazell TJ. Leptin and energy balance: exploring Leptin's role in the regulation of energy intake and energy expenditure. Nutr Neurosci 2024; 27:87-95. [PMID: 36583502 DOI: 10.1080/1028415x.2022.2161135] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Leptin is a tonic appetite-regulating hormone, which is integral for the long-term regulation of energy balance. The current evidence suggests that the typical orexigenic or anorexigenic response of many of these appetite-regulating hormones, most notably ghrelin and cholecystokinin (CCK), require leptin to function whereas glucagon-like peptide-1 (GLP-1) is required for leptin to function, and these responses are altered when leptin injection or gene therapy is administered in combination with these same hormones or respective agonists. The appetite-regulatory pathway is complex, thus peptide tyrosine tyrosine (PYY), brain-derived neurotrophic factor (BDNF), orexin-A (OXA), and amylin also maintain ties to leptin, however these are less well understood. While reviews to date have focused on the existing relationships between leptin and the various neuropeptide modulators of appetite within the central nervous system (CNS) or it's role in thermogenesis, no review paper has synthesised the information regarding the interactions between appetite-regulating hormones and how leptin as a chronic regulator of energy balance can influence the acute appetite-regulatory response. Current evidence suggests that potential relationships exist between leptin and the circulating peripheral appetite hormones ghrelin, GLP-1, CCK, OXA and amylin to exhibit either synergistic or opposing effects on appetite inhibition. Though more research is warranted, leptin appears to be integral in both energy intake and energy expenditure. More specifically, functional leptin receptors appear to play an essential role in these processes.
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Affiliation(s)
- Jessica A L Tucker
- Department of Kinesiology and Physical Education, Wilfrid Laurier University, Waterloo, Canada
| | - Derek P D Bornath
- Department of Kinesiology and Physical Education, Wilfrid Laurier University, Waterloo, Canada
| | - Seth F McCarthy
- Department of Kinesiology and Physical Education, Wilfrid Laurier University, Waterloo, Canada
| | - Tom J Hazell
- Department of Kinesiology and Physical Education, Wilfrid Laurier University, Waterloo, Canada
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14
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Tschöp MH, Friedman JM. Seeking satiety: From signals to solutions. Sci Transl Med 2023; 15:eadh4453. [PMID: 37992155 DOI: 10.1126/scitranslmed.adh4453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 11/03/2023] [Indexed: 11/24/2023]
Abstract
Remedies for the treatment of obesity date to Hippocrates, when patients with obesity were directed to "reduce food and avoid drinking to fullness" and begin "running during the night." Similar recommendations have been repeated ever since, despite the fact that they are largely ineffective. Recently, highly effective therapeutics were developed that may soon enable physicians to manage body weight in patients with obesity in a manner similar to the way that blood pressure is controlled in patients with hypertension. These medicines have grown out of a revolution in our understanding of the molecular and neural control of appetite and body weight, reviewed here.
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Affiliation(s)
- Matthias H Tschöp
- Helmholtz Munich and Technical University Munich, Munich, 85758 Germany
| | - Jeffrey M Friedman
- Laboratory of Molecular Genetics, Howard Hughes Medical Institute, Rockefeller University, New York, NY 10065 USA
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15
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Kloock S, Ziegler CG, Dischinger U. Obesity and its comorbidities, current treatment options and future perspectives: Challenging bariatric surgery? Pharmacol Ther 2023; 251:108549. [PMID: 37879540 DOI: 10.1016/j.pharmthera.2023.108549] [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: 08/08/2023] [Revised: 10/08/2023] [Accepted: 10/19/2023] [Indexed: 10/27/2023]
Abstract
Obesity and its comorbidities, including type 2 diabetes mellitus, cardiovascular disease, heart failure and non-alcoholic liver disease are a major health and economic burden with steadily increasing numbers worldwide. The need for effective pharmacological treatment options is strong, but, until recently, only few drugs have proven sufficient efficacy and safety. This article provides a comprehensive overview of obesity and its comorbidities, with a special focus on organ-specific pathomechanisms. Bariatric surgery as the so far most-effective therapeutic strategy, current pharmacological treatment options and future treatment strategies will be discussed. An increasing knowledge about the gut-brain axis and especially the identification and physiology of incretins unfolds a high number of potential drug candidates with impressive weight-reducing potential. Future multi-modal therapeutic concepts in obesity treatment may surpass the effectivity of bariatric surgery not only with regard to weight loss, but also to associated comorbidities.
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Affiliation(s)
- Simon Kloock
- Department of Internal Medicine, Division of Endocrinology and Diabetes, University Hospital, University of Würzburg, Würzburg, Germany
| | - Christian G Ziegler
- Department of Internal Medicine, Division of Endocrinology and Diabetes, University Hospital, University of Würzburg, Würzburg, Germany; Department of Internal Medicine III, University Hospital Carl Gustav Carus Dresden, Dresden, Germany
| | - Ulrich Dischinger
- Department of Internal Medicine, Division of Endocrinology and Diabetes, University Hospital, University of Würzburg, Würzburg, Germany; Comprehensive Heart Failure Center, Würzburg, Germany.
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16
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Szczerbinski L, Florez JC. Precision medicine of obesity as an integral part of type 2 diabetes management - past, present, and future. Lancet Diabetes Endocrinol 2023; 11:861-878. [PMID: 37804854 DOI: 10.1016/s2213-8587(23)00232-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 07/29/2023] [Accepted: 08/01/2023] [Indexed: 10/09/2023]
Abstract
Obesity is a complex and heterogeneous condition that leads to various metabolic complications, including type 2 diabetes. Unfortunately, for some, treatment options to date for obesity are insufficient, with many people not reaching sustained weight loss or having improvements in metabolic health. In this Review, we discuss advances in the genetics of obesity from the past decade-with emphasis on developments from the past 5 years-with a focus on metabolic consequences, and their potential implications for precision management of the disease. We also provide an overview of the potential role of genetics in guiding weight loss strategies. Finally, we propose a vision for the future of precision obesity management that includes developing an obesity-centred multidisease management algorithm that targets both obesity and its comorbidities. However, further collaborative efforts and research are necessary to fully realise its potential and improve metabolic health outcomes.
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Affiliation(s)
- Lukasz Szczerbinski
- Diabetes Unit, Endocrine Division, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA; Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA; Programs in Metabolism and Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA; Clinical Research Centre, Medical University of Bialystok, Bialystok, Poland; Department of Endocrinology, Diabetology and Internal Medicine, Medical University of Bialystok, Bialystok, Poland
| | - Jose C Florez
- Department of Medicine, Massachusetts General Hospital, Boston, MA, USA; Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA; Programs in Metabolism and Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA, USA.
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17
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Kokkorakis M, Katsarou A, Katsiki N, Mantzoros CS. Milestones in the journey towards addressing obesity; Past trials and triumphs, recent breakthroughs, and an exciting future in the era of emerging effective medical therapies and integration of effective medical therapies with metabolic surgery. Metabolism 2023; 148:155689. [PMID: 37689110 DOI: 10.1016/j.metabol.2023.155689] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 08/28/2023] [Accepted: 08/28/2023] [Indexed: 09/11/2023]
Abstract
The 21st century is characterized by an increasing incidence and prevalence of obesity and the burden of its associated comorbidities, especially cardiometabolic diseases, which are reaching pandemic proportions. In the late '90s, the "black box" of adipose tissue and energy homeostasis was opened with the discovery of leptin, transforming the adipose tissue from an "inert fat-storage organ" to the largest human endocrine organ and creating the basis on which more intensified research efforts to elucidate the pathogenesis of obesity and develop novel treatments were based upon. Even though leptin was eventually not proven to be the "standalone magic bullet" for the treatment of common/polygenic obesity, it has been successful in the treatment of monogenic obesity syndromes. Additionally, it shifted the paradigm of treating obesity from a condition due to "lack of willpower" to a disease due to distinct underlying biological mechanisms for which specific pharmacotherapies would be needed in addition to lifestyle modification. Subsequently, the melanocortin pathway proved to be an equally valuable pathway for the pharmacotherapy of obesity. Melanocortin receptor agonists have recently been approved for treating certain types of syndromic obesity. Other molecules- such as incretins, implicated in energy and glucose homeostasis- are secreted by the gastrointestinal tract. Glucagon-like peptide 1 (GLP-1) is the most prominent one, with GLP-1 analogs approved for common/polygenic obesity. Unimolecular combinations with other incretins, e.g., GLP-1 with gastric inhibitory polypeptide and/or glucagon, are expected to be approved soon as more effective pharmacotherapies for obesity and its comorbidities. Unimolecular combinations with other compounds and small molecules activating the receptors of these molecules are currently under investigation as promising future pharmacotherapies. Moreover, metabolic and bariatric surgery has also demonstrated impressive results, especially in the case of morbid obesity. Consequently, this broadening therapeutic armamentarium calls for a well-thought-after and well-coordinated multidisciplinary approach, for instance, through cardiometabolic expertise centers, that would ideally address effectively and cost-effectively obesity and its comorbidities, providing tangible benefits to large segments of the population.
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Affiliation(s)
- Michail Kokkorakis
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Angeliki Katsarou
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Niki Katsiki
- Department of Nutritional Sciences and Dietetics, International Hellenic University, 57400 Thessaloniki, Greece
| | - Christos S Mantzoros
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Section of Endocrinology, VA Boston Healthcare System, Harvard Medical School, Boston, MA 02115, USA.
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18
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Speakman JR, Hall KD. Models of body weight and fatness regulation. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220231. [PMID: 37661735 PMCID: PMC10475878 DOI: 10.1098/rstb.2022.0231] [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: 04/14/2023] [Accepted: 07/13/2023] [Indexed: 09/05/2023] Open
Abstract
Body weight and fatness appear to be regulated phenomena. Several different theoretical models are available to capture the essence of this idea. These include the set-point, dynamic equilibrium, adiposity force, control theory-settling point, Hall-Guo, operation point and dual intervention point (DIP) models. The set-point model posits a single reference point around which levels of fat are regulated. The dynamic equilibrium model suggests that the apparent regulation of body fat around a reference point is an illusion owing to the necessary impacts of weight change on energy expenditure. Control theory focuses on the importance of feedback gain and suggests set-point and dynamic equilibrium are ends of a continuum of feedback gain. Control theory models have also been called 'settling point' models. The Hall-Guo, operation point and DIP models also bring together the set-point and dynamic equilibrium ideas into a single framework. The DIP proposes a zone of indifference where dynamic equilibrium 'regulation' predominates, bounded by upper and lower intervention points beyond which physiological mechanisms are activated. The drifty gene hypothesis is an idea explaining where this individual variation in the upper intervention point might come from. We conclude that further experiments to test between the models are sorely required. This article is part of a discussion meeting issue 'Causes of obesity: theories, conjectures and evidence (Part II)'.
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Affiliation(s)
- John R. Speakman
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong Province, 518055, People's Republic of China
- School of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, UK
- Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, People's Republic of China
- China Medical University, Shenyang, Liaoning Province, 110122, People's Republic of China
| | - Kevin D. Hall
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
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19
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Jansson JO, Anesten F, Hägg D, Zlatkovic J, Dickson SL, Jansson PA, Schéle E, Bellman J, Ohlsson C. The dual hypothesis of homeostatic body weight regulation, including gravity-dependent and leptin-dependent actions. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220219. [PMID: 37661748 PMCID: PMC10475867 DOI: 10.1098/rstb.2022.0219] [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: 05/06/2023] [Accepted: 06/27/2023] [Indexed: 09/05/2023] Open
Abstract
Body weight is tightly regulated when outside the normal range. It has been proposed that there are individual-specific lower and upper intervention points for when the homeostatic regulation of body weight is initiated. The nature of the homeostatic mechanisms regulating body weight at the lower and upper ends of the body weight spectrum might differ. Previous studies demonstrate that leptin is the main regulator of body weight at the lower end of the body weight spectrum. We have proposed that land-living animals use gravity to regulate their body weight. We named this homeostatic system the gravitostat and proposed that there are two components of the gravitostat. First, an obvious mechanism involves increased energy consumption in relation to body weight when working against gravity on land. In addition, we propose that there exists a component, involving sensing of the body weight by osteocytes in the weight-bearing bones, resulting in a feedback regulation of energy metabolism and body weight. The gravity-dependent homeostatic regulation is mainly active in obese mice. We, herein, propose the dual hypothesis of body weight regulation, including gravity-dependent actions (= gravitostat) at the upper end and leptin-dependent actions at the lower end of the body weight spectrum. This article is part of a discussion meeting issue 'Causes of obesity: theories, conjectures and evidence (Part II)'.
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Affiliation(s)
- John-Olov Jansson
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-41390 Göteborg, Västra Götaland, Sweden
| | - Frederik Anesten
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-41390 Göteborg, Västra Götaland, Sweden
| | - Daniel Hägg
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-41390 Göteborg, Västra Götaland, Sweden
| | - Jovana Zlatkovic
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-41390 Göteborg, Västra Götaland, Sweden
| | - Suzanne L. Dickson
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-41390 Göteborg, Västra Götaland, Sweden
| | - Per-Anders Jansson
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-41390 Göteborg, Västra Götaland, Sweden
| | - Erik Schéle
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-41390 Göteborg, Västra Götaland, Sweden
| | - Jakob Bellman
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-41390 Göteborg, Västra Götaland, Sweden
| | - Claes Ohlsson
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-41390 Göteborg, Västra Götaland, Sweden
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20
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Brüning JC, Fenselau H. Integrative neurocircuits that control metabolism and food intake. Science 2023; 381:eabl7398. [PMID: 37769095 DOI: 10.1126/science.abl7398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 08/31/2023] [Indexed: 09/30/2023]
Abstract
Systemic metabolism has to be constantly adjusted to the variance of food intake and even be prepared for anticipated changes in nutrient availability. Therefore, the brain integrates multiple homeostatic signals with numerous cues that predict future deviations in energy supply. Recently, our understanding of the neural pathways underlying these regulatory principles-as well as their convergence in the hypothalamus as the key coordinator of food intake, energy expenditure, and glucose metabolism-have been revealed. These advances have changed our view of brain-dependent control of metabolic physiology. In this Review, we discuss new concepts about how alterations in these pathways contribute to the development of prevalent metabolic diseases such as obesity and type 2 diabetes mellitus and how this emerging knowledge may provide new targets for their treatment.
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Affiliation(s)
- Jens C Brüning
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, 50931 Cologne, Germany
- Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, 50924 Cologne, Germany
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
- National Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Henning Fenselau
- Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, 50924 Cologne, Germany
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
- Research Group Synaptic Transmission in Energy Homeostasis, Max Planck Institute for Metabolism Research, 50931 Cologne, Germany
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21
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Chen YK, Liu TT, Teia FKF, Xie MZ. Exploring the underlying mechanisms of obesity and diabetes and the potential of Traditional Chinese Medicine: an overview of the literature. Front Endocrinol (Lausanne) 2023; 14:1218880. [PMID: 37600709 PMCID: PMC10433171 DOI: 10.3389/fendo.2023.1218880] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 07/18/2023] [Indexed: 08/22/2023] Open
Abstract
Obesity and diabetes are closely related metabolic disorders that have become major public health concerns worldwide. Over the past few decades, numerous studies have explored the underlying mechanisms of these disorders and identified various risk factors, including genetics, lifestyle, and dietary habits. Traditional Chinese Medicine (TCM) has been increasingly recognized for its potential to manage obesity and diabetes. Weight loss is difficult to sustain, and several diabetic therapies, such as sulfonylureas, thiazolidinediones, and insulin, might make it harder to lose weight. While lifestyle changes should be the primary approach for people interested in lowering weight, drugs are also worth investigating. Since some of the newer glucose-lowering medications that cause weight loss, such as glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and sodium-glucose cotransporter 2 inhibitors (SGLT2i), are additionally utilized or are under consideration for use as anti-obesity drugs, the frontier between glucose-lowering medication and weight loss drugs appears to be shifting. This review provides an overview of the literature on the underlying mechanisms of obesity and diabetes and the prospect of TCM in their management. We discuss the various TCM interventions, including acupuncture, herbal medicine, and dietary therapy, and their effects on metabolic health. We also highlight the potential of TCM in regulating gut microbiota, reducing inflammation, and improving insulin sensitivity. The findings suggest that TCM may provide a promising approach to preventing and managing obesity and diabetes. However, further well-designed studies are needed to confirm the efficacy and safety of TCM interventions and to elucidate their underlying mechanisms of action.
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Affiliation(s)
- Yan-kun Chen
- School of Chinese Medicine, Hunan University of Chinese Medicine, Changsha, China
- Hunan Engineering Technology Research Center for Medicinal and Functional Food, Hunan University of Chinese Medicine, Changsha, China
- Key Laboratory of TCM Heart and Lung Syndrome Differentiation and Medicated Diet and Dietotherapy, Hunan University of Chinese Medicine, Changsha, China
| | - Ting-ting Liu
- School of Chinese Medicine, Hunan University of Chinese Medicine, Changsha, China
- Hunan Engineering Technology Research Center for Medicinal and Functional Food, Hunan University of Chinese Medicine, Changsha, China
- Key Laboratory of TCM Heart and Lung Syndrome Differentiation and Medicated Diet and Dietotherapy, Hunan University of Chinese Medicine, Changsha, China
| | - Farah Khameis Farag Teia
- Department of Agro-technology, Medicinal and Aromatic Plants and Traditional Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Meng-zhou Xie
- School of Chinese Medicine, Hunan University of Chinese Medicine, Changsha, China
- Hunan Engineering Technology Research Center for Medicinal and Functional Food, Hunan University of Chinese Medicine, Changsha, China
- Key Laboratory of TCM Heart and Lung Syndrome Differentiation and Medicated Diet and Dietotherapy, Hunan University of Chinese Medicine, Changsha, China
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22
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Rosenbaum M, Foster G. Differential mechanisms affecting weight loss and weight loss maintenance. Nat Metab 2023; 5:1266-1274. [PMID: 37612402 DOI: 10.1038/s42255-023-00864-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 07/13/2023] [Indexed: 08/25/2023]
Abstract
In most lifestyle, pharmacological and surgical interventions, weight loss occurs over an approximately 6- to 9-month period and is followed by a weight plateau and then weight regain. Overall, only about 15% of individuals can sustain a 10% or greater non-surgical, non-pharmacological, weight loss. A key question is the degree to which the genotypes, phenotypes and environmental correlates of success in weight loss and weight loss maintenance are continuous or dichotomous. This Perspective is a comparison of the interactions of weight loss and maintenance with genetic, behavioural, physiological and environmental homeostatic systems and a discussion of the implications of these findings for research in, and treatment of, obesity. Data suggest that weight loss and weight loss maintenance are physiologically and psychologically different in many ways. Consequently, individuals may require different interventions designed for temporarily sustaining a negative energy balance during weight loss versus permanently maintaining energy balance after weight loss.
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Affiliation(s)
- Michael Rosenbaum
- Columbia University Irving Medical Center, Departments of Pediatrics and Medicine, Division of Molecular Genetics and the Irving Center for Clinical and Translational Research (MR), New York, NY, USA.
| | - Gary Foster
- WW International, Perelman School of Medicine at the University of Pennsylvania, Department of Psychiatry, Weight and Eating Disorders Program (GF), New York, NY, USA
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23
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Sumithran P. The Physiological Regulation of Body Fat Mass. Gastroenterol Clin North Am 2023; 52:295-310. [PMID: 37197874 DOI: 10.1016/j.gtc.2023.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Disturbances inbody weight and adiposity in both humans and animals are met by compensatory adjustments in energy intake and energy expenditure, suggesting that body weight or fat is regulated. From a clinical viewpoint, this is likely to contribute to the difficulty that many people with obesity have in maintaining weight loss. Finding ways to modify these physiologic responses is likely to improve the long-term success of obesity treatments.
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Affiliation(s)
- Priya Sumithran
- Department of Medicine (St Vincent's), University of Melbourne, St Vincent's Hospital, Clinical Science Building Level 4, 29 Regent Street, Fitzroy, Victoria 3065, Australia; Department of Endocrinology, Austin Health.
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24
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Würfel M, Blüher M, Stumvoll M, Ebert T, Kovacs P, Tönjes A, Breitfeld J. Adipokines as Clinically Relevant Therapeutic Targets in Obesity. Biomedicines 2023; 11:biomedicines11051427. [PMID: 37239098 DOI: 10.3390/biomedicines11051427] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/04/2023] [Accepted: 05/08/2023] [Indexed: 05/28/2023] Open
Abstract
Adipokines provide an outstanding role in the comprehensive etiology of obesity and may link adipose tissue dysfunction to further metabolic and cardiovascular complications. Although several adipokines have been identified in terms of their physiological roles, many regulatory circuits remain unclear and translation from experimental studies to clinical applications has yet to occur. Nevertheless, due to their complex metabolic properties, adipokines offer immense potential for their use both as obesity-associated biomarkers and as relevant treatment strategies for overweight, obesity and metabolic comorbidities. To provide an overview of the current clinical use of adipokines, this review summarizes clinical studies investigating the potential of various adipokines with respect to diagnostic and therapeutic treatment strategies for obesity and linked metabolic disorders. Furthermore, an overview of adipokines, for which a potential for clinical use has been demonstrated in experimental studies to date, will be presented. In particular, promising data revealed that fibroblast growth factor (FGF)-19, FGF-21 and leptin offer great potential for future clinical application in the treatment of obesity and related comorbidities. Based on data from animal studies or other clinical applications in addition to obesity, adipokines including adiponectin, vaspin, resistin, chemerin, visfatin, bone morphogenetic protein 7 (BMP-7) and tumor necrosis factor alpha (TNF-α) provide potential for human clinical application.
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Affiliation(s)
- Marleen Würfel
- Department of Medicine III, Division of Endocrinology, Nephrology and Rheumatology, University of Leipzig, Liebigstr. 18, 04103 Leipzig, Germany
| | - Matthias Blüher
- Department of Medicine III, Division of Endocrinology, Nephrology and Rheumatology, University of Leipzig, Liebigstr. 18, 04103 Leipzig, Germany
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG), Helmholtz Center Munich at the University of Leipzig and the University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Michael Stumvoll
- Department of Medicine III, Division of Endocrinology, Nephrology and Rheumatology, University of Leipzig, Liebigstr. 18, 04103 Leipzig, Germany
| | - Thomas Ebert
- Department of Medicine III, Division of Endocrinology, Nephrology and Rheumatology, University of Leipzig, Liebigstr. 18, 04103 Leipzig, Germany
| | - Peter Kovacs
- Department of Medicine III, Division of Endocrinology, Nephrology and Rheumatology, University of Leipzig, Liebigstr. 18, 04103 Leipzig, Germany
- German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Anke Tönjes
- Department of Medicine III, Division of Endocrinology, Nephrology and Rheumatology, University of Leipzig, Liebigstr. 18, 04103 Leipzig, Germany
| | - Jana Breitfeld
- Department of Medicine III, Division of Endocrinology, Nephrology and Rheumatology, University of Leipzig, Liebigstr. 18, 04103 Leipzig, Germany
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25
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Flier JS. Moderating "the great debate": The carbohydrate-insulin vs. the energy balance models of obesity. Cell Metab 2023; 35:737-741. [PMID: 37086719 DOI: 10.1016/j.cmet.2023.03.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/17/2023] [Accepted: 03/30/2023] [Indexed: 04/24/2023]
Abstract
The increased prevalence of obesity in recent decades is a topic of great scientific and medical interest, but despite many advances, the causes of this increase have not been adequately identified. In this context, two conflicting models for obesity-the carbohydrate-insulin model (CIM) and the energy balance model (EBM)-are being vigorously debated by distinct cohorts of experts in the field. The goal of this perspective is to assess this "conflict of models" from a neutral perspective. I conclude that although both models have produced useful insights, they differ fundamentally in what they seek to explain, and neither has yet provided a validated mechanistic account for the rising obesity prevalence in some but not all members of the population. Rather than engaging in such debates over competing models, the field should be more focused on establishing specific mechanistic insights in identified patient groups and, eventually, actionable interventions based on them.
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Affiliation(s)
- Jeffrey S Flier
- Department of Neurobiology and Medicine, Harvard Medical School, Boston, MA, USA.
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26
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Han Y, He Y, Harris L, Xu Y, Wu Q. Identification of a GABAergic neural circuit governing leptin signaling deficiency-induced obesity. eLife 2023; 12:e82649. [PMID: 37043384 PMCID: PMC10097419 DOI: 10.7554/elife.82649] [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: 08/11/2022] [Accepted: 03/24/2023] [Indexed: 04/13/2023] Open
Abstract
The hormone leptin is known to robustly suppress food intake by acting upon the leptin receptor (LepR) signaling system residing within the agouti-related protein (AgRP) neurons of the hypothalamus. However, clinical studies indicate that leptin is undesirable as a therapeutic regiment for obesity, which is at least partly attributed to the poorly understood complex secondary structure and key signaling mechanism of the leptin-responsive neural circuit. Here, we show that the LepR-expressing portal neurons send GABAergic projections to a cohort of α3-GABAA receptor expressing neurons within the dorsomedial hypothalamic nucleus (DMH) for the control of leptin-mediated obesity phenotype. We identified the DMH as a key brain region that contributes to the regulation of leptin-mediated feeding. Acute activation of the GABAergic AgRP-DMH circuit promoted food intake and glucose intolerance, while activation of post-synaptic MC4R neurons in the DMH elicited exactly opposite phenotypes. Rapid deletion of LepR from AgRP neurons caused an obesity phenotype which can be rescued by blockage of GABAA receptor in the DMH. Consistent with behavioral results, these DMH neurons displayed suppressed neural activities in response to hunger or hyperglycemia. Furthermore, we identified that α3-GABAA receptor signaling within the DMH exerts potent bi-directional regulation of the central effects of leptin on feeding and body weight. Together, our results demonstrate a novel GABAergic neural circuit governing leptin-mediated feeding and energy balance via a unique α3-GABAA signaling within the secondary leptin-responsive neural circuit, constituting a new avenue for therapeutic interventions in the treatment of obesity and associated comorbidities.
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Affiliation(s)
- Yong Han
- USDA/ARS Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of MedicineHoustonUnited States
| | - Yang He
- USDA/ARS Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of MedicineHoustonUnited States
| | - Lauren Harris
- USDA/ARS Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of MedicineHoustonUnited States
| | - Yong Xu
- USDA/ARS Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of MedicineHoustonUnited States
| | - Qi Wu
- USDA/ARS Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of MedicineHoustonUnited States
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27
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Saxton RA, Caveney NA, Moya-Garzon MD, Householder KD, Rodriguez GE, Burdsall KA, Long JZ, Garcia KC. Structural insights into the mechanism of leptin receptor activation. Nat Commun 2023; 14:1797. [PMID: 37002197 PMCID: PMC10066393 DOI: 10.1038/s41467-023-37169-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 03/04/2023] [Indexed: 04/03/2023] Open
Abstract
Leptin is an adipocyte-derived protein hormone that promotes satiety and energy homeostasis by activating the leptin receptor (LepR)-STAT3 signaling axis in a subset of hypothalamic neurons. Leptin signaling is dysregulated in obesity, however, where appetite remains elevated despite high levels of circulating leptin. To gain insight into the mechanism of leptin receptor activation, here we determine the structure of a stabilized leptin-bound LepR signaling complex using single particle cryo-EM. The structure reveals an asymmetric architecture in which a single leptin induces LepR dimerization via two distinct receptor-binding sites. Analysis of the leptin-LepR binding interfaces reveals the molecular basis for human obesity-associated mutations. Structure-based design of leptin variants that destabilize the asymmetric LepR dimer yield both partial and biased agonists that partially suppress STAT3 activation in the presence of wild-type leptin and decouple activation of STAT3 from LepR negative regulators. Together, these results reveal the structural basis for LepR activation and provide insights into the differential plasticity of signaling pathways downstream of LepR.
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Affiliation(s)
- Robert A Saxton
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, 94305, USA.
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA, 94720, USA.
| | - Nathanael A Caveney
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Maria Dolores Moya-Garzon
- Department of Pathology, Stanford University School of Medicine, Sarafan ChEM-H, Stanford University, Stanford, CA, USA
| | - Karsten D Householder
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Grayson E Rodriguez
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, 94305, USA
- Program in Immunology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Kylie A Burdsall
- Cancer Biology Program, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Jonathan Z Long
- Department of Pathology, Stanford University School of Medicine, Sarafan ChEM-H, Stanford University, Stanford, CA, USA
| | - K Christopher Garcia
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, 94305, USA.
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, 94305, USA.
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, 94305, USA.
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28
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Wang S, Neufurth M, Schepler H, Tan R, She Z, Al-Nawas B, Wang X, Schröder HC, Müller WEG. Acceleration of Wound Healing through Amorphous Calcium Carbonate, Stabilized with High-Energy Polyphosphate. Pharmaceutics 2023; 15:pharmaceutics15020494. [PMID: 36839816 PMCID: PMC9961744 DOI: 10.3390/pharmaceutics15020494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/28/2023] [Accepted: 01/29/2023] [Indexed: 02/05/2023] Open
Abstract
Amorphous calcium carbonate (ACC), precipitated in the presence of inorganic polyphosphate (polyP), has shown promise as a material for bone regeneration due to its morphogenetic and metabolic energy (ATP)-delivering properties. The latter activity of the polyP-stabilized ACC ("ACC∙PP") particles is associated with the enzymatic degradation of polyP, resulting in the transformation of ACC into crystalline polymorphs. In a novel approach, stimulated by these results, it was examined whether "ACC∙PP" also promotes the healing of skin injuries, especially chronic wounds. In in vitro experiments, "ACC∙PP" significantly stimulated the migration of endothelial cells, both in tube formation and scratch assays (by 2- to 3-fold). Support came from ex vivo experiments showing increased cell outgrowth in human skin explants. The transformation of ACC into insoluble calcite was suppressed by protein/serum being present in wound fluid. The results were confirmed in vivo in studies on normal (C57BL/6) and diabetic (db/db) mice. Topical administration of "ACC∙PP" significantly accelerated the rate of re-epithelialization, particularly in delayed healing wounds in diabetic mice (day 7: 1.5-fold; and day 13: 1.9-fold), in parallel with increased formation/maturation of granulation tissue. The results suggest that administration of "ACC∙PP" opens a new strategy to improve ATP-dependent wound healing, particularly in chronic wounds.
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Affiliation(s)
- Shunfeng Wang
- ERC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany
| | - Meik Neufurth
- ERC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany
| | - Hadrian Schepler
- Department of Dermatology, University Clinic Mainz, Langenbeckstr. 1, D-55131 Mainz, Germany
| | - Rongwei Tan
- Shenzhen Lando Biomaterials Co., Ltd., Building B3, Unit 2B-C, China Merchants Guangming Science Park, Guangming District, Shenzhen 518107, China
| | - Zhending She
- Shenzhen Lando Biomaterials Co., Ltd., Building B3, Unit 2B-C, China Merchants Guangming Science Park, Guangming District, Shenzhen 518107, China
| | - Bilal Al-Nawas
- Clinic for Oral and Maxillofacial Surgery and Plastic Surgery, University Medical Center of the Johannes Gutenberg University, Augustusplatz 2, D-55131 Mainz, Germany
| | - Xiaohong Wang
- ERC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany
| | - Heinz C. Schröder
- ERC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany
- Correspondence: (H.C.S.); (W.E.G.M.)
| | - Werner E. G. Müller
- ERC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany
- Correspondence: (H.C.S.); (W.E.G.M.)
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29
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De Jesus AN, Henry BA. The role of oestrogen in determining sexual dimorphism in energy balance. J Physiol 2023; 601:435-449. [PMID: 36117117 PMCID: PMC10092637 DOI: 10.1113/jp279501] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 07/26/2022] [Indexed: 02/03/2023] Open
Abstract
Energy balance is determined by caloric intake and the rate at which energy is expended, with the latter comprising resting energy expenditure, physical activity and adaptive thermogenesis. The regulation of both energy intake and expenditure exhibits clear sexual dimorphism, with young women being relatively protected against weight gain and the development of cardiometabolic diseases. Preclinical studies have indicated that females are more sensitive to the satiety effects of leptin and insulin compared to males. Furthermore, females have greater thermogenic activity than males, whereas resting energy expenditure is generally higher in males than females. In addition to this, in post-menopausal women, the decline in sex steroid concentration, particularly in oestrogen, is associated with a shift in the distribution of adipose tissue and overall increased propensity to gain weight. Oestrogens are known to regulate energy balance and weight homeostasis via effects on both food intake and energy expenditure. Indeed, 17β-oestradiol treatment increases melanocortin signalling in the hypothalamus to cause satiety. Furthermore, oestrogenic action at the ventromedial hypothalamus has been linked with increased energy expenditure in female mice. We propose that oestrogen action on energy balance is multi-faceted and is fundamental to determining sexual dimorphism in weight control. Furthermore, evidence suggests that the decline in oestrogen levels leads to increased risk of weight gain and development of cardiometabolic disease in women across the menopausal transition.
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Affiliation(s)
- Anne Nicole De Jesus
- Metabolism, Obesity and Diabetes Program, Biomedicine, Discovery Institute, Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Belinda A Henry
- Metabolism, Obesity and Diabetes Program, Biomedicine, Discovery Institute, Department of Physiology, Monash University, Clayton, Victoria, Australia
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30
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Hinney A, Körner A, Fischer-Posovszky P. The promise of new anti-obesity therapies arising from knowledge of genetic obesity traits. Nat Rev Endocrinol 2022; 18:623-637. [PMID: 35902734 PMCID: PMC9330928 DOI: 10.1038/s41574-022-00716-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/17/2022] [Indexed: 02/07/2023]
Abstract
Obesity is a multifactorial and complex disease that often manifests in early childhood with a lifelong burden. Polygenic and monogenic obesity are driven by the interaction between genetic predisposition and environmental factors. Polygenic variants are frequent and confer small effect sizes. Rare monogenic obesity syndromes are caused by defined pathogenic variants in single genes with large effect sizes. Most of these genes are involved in the central nervous regulation of body weight; for example, genes of the leptin-melanocortin pathway. Clinically, patients with monogenic obesity present with impaired satiety, hyperphagia and pronounced food-seeking behaviour in early childhood, which leads to severe early-onset obesity. With the advent of novel pharmacological treatment options emerging for monogenic obesity syndromes that target the central melanocortin pathway, genetic testing is recommended for patients with rapid weight gain in infancy and additional clinical suggestive features. Likewise, patients with obesity associated with hypothalamic damage or other forms of syndromic obesity involving energy regulatory circuits could benefit from these novel pharmacological treatment options. Early identification of patients affected by syndromic obesity will lead to appropriate treatment, thereby preventing the development of obesity sequelae, avoiding failure of conservative treatment approaches and alleviating stigmatization of patients and their families.
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Affiliation(s)
- Anke Hinney
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy and University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
- Center for Translational Neuro- and Behavioral Sciences, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
| | - Antje Körner
- Leipzig University, Medical Faculty, Hospital for Children and Adolescents, Centre of Paediatric Research (CPL), Leipzig, Germany
- LIFE Child, Leipzig Research Centre for Civilization Diseases, Leipzig, Germany
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany
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31
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Shi Y, Kim H, Hamann CA, Rhea EM, Brunger JM, Lippmann ES. Nuclear receptor ligand screening in an iPSC-derived in vitro blood-brain barrier model identifies new contributors to leptin transport. Fluids Barriers CNS 2022; 19:77. [PMID: 36131285 PMCID: PMC9494897 DOI: 10.1186/s12987-022-00375-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 06/15/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The hormone leptin exerts its function in the brain to reduce food intake and increase energy expenditure to prevent obesity. However, most obese subjects reflect the resistance to leptin even with elevated serum leptin. Considering that leptin must cross the blood-brain barrier (BBB) in several regions to enter the brain parenchyma, altered leptin transport through the BBB might play an important role in leptin resistance and other biological conditions. Here, we report the use of a human induced pluripotent stem cell (iPSC)-derived BBB model to explore mechanisms that influence leptin transport. METHODS iPSCs were differentiated into brain microvascular endothelial cell (BMEC)-like cells using standard methods. BMEC-like cells were cultured in Transwell filters, treated with ligands from a nuclear receptor agonist library, and assayed for leptin transport using an enzyme-linked immune sorbent assay. RNA sequencing was further used to identify differentially regulated genes and pathways. The role of a select hit in leptin transport was tested with the competitive substrate assay and after gene knockdown using CRISPR techniques. RESULTS Following a screen of 73 compounds, 17β-estradiol was identified as a compound that could significantly increase leptin transport. RNA sequencing revealed many differentially expressed transmembrane transporters after 17β-estradiol treatment. Of these, cationic amino acid transporter-1 (CAT-1, encoded by SLC7A1) was selected for follow-up analyses due to its high and selective expression in BMECs in vivo. Treatment of BMEC-like cells with CAT-1 substrates, as well as knockdown of CAT-1 expression via CRISPR-mediated epigenome editing, yielded significant increases in leptin transport. CONCLUSIONS A major female sex hormone, as well as an amino acid transporter, were revealed as regulators of leptin BBB transport in the iPSC-derived BBB model. Outcomes from this work provide insights into regulation of hormone transport across the BBB.
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Affiliation(s)
- Yajuan Shi
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA
| | - Hyosung Kim
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA
| | - Catherine A Hamann
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Elizabeth M Rhea
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, USA.,Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
| | - Jonathan M Brunger
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA.,Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN, USA
| | - Ethan S Lippmann
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA. .,Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA. .,Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN, USA. .,Interdisciplinary Materials Science Program, Vanderbilt University, Nashville, TN, USA. .,Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA. .,Vanderbilt Brain Institute, Vanderbilt University Medical Center, Nashville, TN, USA. .,Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA.
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32
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Mayer O, Bruthans J, Seidlerová J, Gelžinský J, Kučera R, Karnosová P, Mateřánková M, Wohlfahrt P, Cífková R, Filipovský J. High leptin status indicates an increased risk of mortality and heart failure in stable coronary artery disease. Nutr Metab Cardiovasc Dis 2022; 32:2137-2146. [PMID: 35843790 DOI: 10.1016/j.numecd.2022.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Revised: 05/31/2022] [Accepted: 06/08/2022] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND AIMS Leptin is an adipocyte-derived peptide involved in energy homeostasis and body weight regulation. The position of leptin in cardiovascular pathophysiology remains controversial. Some studies suggest a detrimental effect of hyperleptinemia on the cardiovascular (CV) system, while others assume the role of leptin as a neutral or even protective factor. We have explored whether high leptin affects the mortality and morbidity risk in patients with stable coronary heart disease. METHODS AND RESULTS We followed 975 patients ≥6 months after myocardial infarction or coronary revascularization in a prospective study. All-cause or cardiovascular death, non-fatal cardiovascular events (recurrent myocardial infarction, stroke, or any revascularization), and hospitalizations for heart failure (HF) we used as outcomes. High serum leptin concentrations (≥18.9 ng/mL, i.e., 4th quartile) were associated with worse survival, as well as with a higher incidence of fatal vascular events or hospitalizations for HF. Even after full adjustment for potential covariates, high leptin remained to be associated with a significantly increased 5-years risk of all-cause death [Hazard risk ratio (HRR) 2.10 (95%CIs:1.29-3.42), p < 0.003], CV death [HRR 2.65 (95%CIs:1.48-4.74), p < 0.001], and HF hospitalization [HRR 1.95 (95% CIs:1.11-3.44), p < 0.020]. In contrast, the incidence risk of non-fatal CV events was only marginally and non-significantly influenced [HRR 1.27 (95%CIs:0.76-2.13), p = 0.359]. CONCLUSIONS High leptin concentration entails an increased risk of mortality, apparently driven by fatal CV events and future worsening of HF, on top of conventional CV risk factors and the baseline status of left ventricular function.
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Affiliation(s)
- Otto Mayer
- 2nd Department of Internal Medicine, Medical Faculty of Charles University and University Hospital, Pilsen, Czech Republic; Biomedical Center, Medical Faculty of Charles University, Pilsen, Czech Republic.
| | - Jan Bruthans
- 2nd Department of Internal Medicine, Medical Faculty of Charles University and University Hospital, Pilsen, Czech Republic; Centre for Cardiovascular Prevention, First Faculty of Medicine, Charles, University and Thomayer Hospital, Prague, Czech Republic
| | - Jitka Seidlerová
- 2nd Department of Internal Medicine, Medical Faculty of Charles University and University Hospital, Pilsen, Czech Republic; Biomedical Center, Medical Faculty of Charles University, Pilsen, Czech Republic
| | - Julius Gelžinský
- 2nd Department of Internal Medicine, Medical Faculty of Charles University and University Hospital, Pilsen, Czech Republic; Biomedical Center, Medical Faculty of Charles University, Pilsen, Czech Republic
| | - Radek Kučera
- Laboratory of Immunochemical Diagnostics, University Hospital, Pilsen, Czech Republic
| | - Petra Karnosová
- 2nd Department of Internal Medicine, Medical Faculty of Charles University and University Hospital, Pilsen, Czech Republic; Biomedical Center, Medical Faculty of Charles University, Pilsen, Czech Republic
| | - Markéta Mateřánková
- 2nd Department of Internal Medicine, Medical Faculty of Charles University and University Hospital, Pilsen, Czech Republic; Biomedical Center, Medical Faculty of Charles University, Pilsen, Czech Republic
| | - Peter Wohlfahrt
- Centre for Cardiovascular Prevention, First Faculty of Medicine, Charles, University and Thomayer Hospital, Prague, Czech Republic
| | - Renata Cífková
- Centre for Cardiovascular Prevention, First Faculty of Medicine, Charles, University and Thomayer Hospital, Prague, Czech Republic
| | - Jan Filipovský
- 2nd Department of Internal Medicine, Medical Faculty of Charles University and University Hospital, Pilsen, Czech Republic; Biomedical Center, Medical Faculty of Charles University, Pilsen, Czech Republic
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33
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Polat SHB, Dariyerli ND. A Physiological Approach to Inflammatory Markers in Obesity. Biomark Med 2022. [DOI: 10.2174/9789815040463122010028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Obesity is one of the most critical health problems all over the world; it is
associated with metabolic dysfunction and overnutrition. Changes in the physiological
function of adipose tissue, leading to altered secretion of adipocytokines, inflammatory
mediators release, and chronic low-grade inflammation, are seen in obesity.
Macrophages, neutrophils, CD4+ and CD8+ T cells, B cells, natural killer T (NKT)
cells, eosinophils, mast cells, and adipocytes are involved in the inflammatory response
that occurs during obesity. Various inflammatory markers are released from these cells.
In this chapter, we will mention inflammatory mechanisms and markers of obesity.
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Speakman JR, Elmquist JK. Obesity: an evolutionary context. LIFE METABOLISM 2022; 1:10-24. [PMID: 36394061 PMCID: PMC9642988 DOI: 10.1093/lifemeta/loac002] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 02/21/2022] [Accepted: 03/09/2022] [Indexed: 05/07/2023]
Abstract
People completely lacking body fat (lipodystrophy/lipoatrophy) and those with severe obesity both show profound metabolic and other health issues. Regulating levels of body fat somewhere between these limits would, therefore, appear to be adaptive. Two different models might be contemplated. More traditional is a set point (SP) where the levels are regulated around a fixed level. Alternatively, dual-intervention point (DIP) is a system that tolerates fairly wide variation but is activated when critically high or low levels are breached. The DIP system seems to fit our experience much better than an SP, and models suggest that it is more likely to have evolved. A DIP system may have evolved because of two contrasting selection pressures. At the lower end, we may have been selected to avoid low levels of fat as a buffer against starvation, to avoid disease-induced anorexia, and to support reproduction. At the upper end, we may have been selected to avoid excess storage because of the elevated risks of predation. This upper limit of control seems to have malfunctioned because some of us deposit large fat stores, with important negative health effects. Why has evolution not protected us against this problem? One possibility is that the protective system slowly fell apart due to random mutations after we dramatically reduced the risk of being predated during our evolutionary history. By chance, it fell apart more in some people than others, and these people are now unable to effectively manage their weight in the face of the modern food glut. To understand the evolutionary context of obesity, it is important to separate the adaptive reason for storing some fat (i.e. the lower intervention point), from the nonadaptive reason for storing lots of fat (a broken upper intervention point). The DIP model has several consequences, showing how we understand the obesity problem and what happens when we attempt to treat it.
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Affiliation(s)
- John R Speakman
- Corresponding author. John R Speakman, Shenzhen Key Laboratory of Metabolic Health, Center for Energy Metabolism and Reproduction, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen, China. E-mail:
| | - Joel K Elmquist
- Joel K. Elmquist, Departments of Internal Medicine and Pharmacology, Center for Hypothalamic Research, University of Texas Southwestern, 5323 Harry Hines blvd., Dallas, TX 75390, USA. E-mail:
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35
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Vosburg RW, Chaar ME, Djouzi SE, Docimo S, Choi D, LaMasters T, Srivastava G, Shukla AP, Oviedo RJ, Fitch A, Azagury DE. Literature review on anti-obesity medication use for metabolic and bariatric surgery patients from the ASMBS clinical issues committee. Surg Obes Relat Dis 2022; 18:1109-1119. [DOI: 10.1016/j.soard.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 07/06/2022] [Indexed: 11/16/2022]
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36
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Kühnen P, Biebermann H, Wiegand S. Pharmacotherapy in Childhood Obesity. Horm Res Paediatr 2022; 95:177-192. [PMID: 34351307 DOI: 10.1159/000518432] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 07/12/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The increasing number of obese children and adolescence is a major problem in health-care systems. Currently, the gold standard for the treatment of these patients with obesity is a multicomponent lifestyle intervention. Unfortunately, this strategy is not leading to a substantial and long-lasting weight loss in the majority of patients. This is the reason why there is an urgent need to establish new treatment strategies for children and adolescents with obesity to reduce the risk for the development of any comorbidities like cardiovascular diseases or diabetes mellitus type 2. SUMMARY In this review, we outline available pharmacological therapeutic options for children and compare the available study data with the outcome of conservative treatment approaches. KEY MESSAGES We discussed, in detail, how knowledge about underlying molecular mechanisms might support the identification of effective antiobesity drugs in the future and in which way this might modulate current treatment strategies to support children and adolescence with obesity to lose body weight.
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Affiliation(s)
- Peter Kühnen
- Institute for Experimental Pediatric Endocrinology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Heike Biebermann
- Institute for Experimental Pediatric Endocrinology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Susanna Wiegand
- Center for Social-Pediatric Care/Pediatric Endocrinology and Diabetology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
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37
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Early and Strong Leptin Reduction Is Predictive for Long-Term Weight Loss during High-Protein, Low-Glycaemic Meal Replacement-A Subanalysis of the Randomised-Controlled ACOORH Trial. Nutrients 2022; 14:nu14122537. [PMID: 35745267 PMCID: PMC9229506 DOI: 10.3390/nu14122537] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/14/2022] [Accepted: 06/15/2022] [Indexed: 02/01/2023] Open
Abstract
Lifestyle interventions including meal replacement are suitable for prevention and treatment of obesity and type-2-diabetes. Since leptin is involved in weight regulation, we hypothesised that a meal replacement-based lifestyle intervention would reduce leptin levels more effectively than lifestyle intervention alone. In the international, multicentre, randomised-controlled ACOORH-trial (Almased-Concept-against-Overweight-and-Obesity-and-Related- Health-Risk), overweight or obese participants with metabolic syndrome criteria (n = 463) were randomised into two groups and received telemonitoring devices and nutritional advice. The intervention group additionally used a protein-rich, low-glycaemic meal replacement. Data were collected at baseline, after 1, 3, 6, and 12 months. All datasets providing leptin data (n = 427) were included in this predefined subanalysis. Serum leptin levels significantly correlated with sex, body mass index, weight, and fat mass at baseline (p < 0.0001). Stronger leptin reduction has been observed in the intervention compared to the control group with the lowest levels after 1 month of intervention (estimated treatment difference −3.4 µg/L [1.4; 5.4] for females; −2.2 µg/L [1.2; 3.3] for males; p < 0.001 each) and was predictive for stronger reduction of body weight and fat mass (p < 0.001 each) over 12 months. Strongest weight loss was observed after 6 months (−5.9 ± 5.1 kg in females of the intervention group vs. −2.9 ± 4.9 kg in the control group (p < 0.0001); −6.8 ± 5.3 kg vs. −4.1 ± 4.4 kg (p = 0.003) in males) and in those participants with combined leptin and insulin decrease. A meal replacement-based lifestyle intervention effectively reduces leptin which is predictive for long-term weight loss.
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SOCS3 Ablation in Leptin Receptor-Expressing Cells Causes Autonomic and Cardiac Dysfunctions in Middle-Aged Mice despite Improving Energy and Glucose Metabolism. Int J Mol Sci 2022; 23:ijms23126484. [PMID: 35742928 PMCID: PMC9223472 DOI: 10.3390/ijms23126484] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/03/2022] [Accepted: 06/06/2022] [Indexed: 02/04/2023] Open
Abstract
Leptin resistance is a hallmark of obesity. Treatments aiming to improve leptin sensitivity are considered a promising therapeutical approach against obesity. However, leptin receptor (LepR) signaling also modulates several neurovegetative aspects, such as the cardiovascular system and hepatic gluconeogenesis. Thus, we investigated the long-term consequences of increased leptin sensitivity, considering the potential beneficial and deleterious effects. To generate a mouse model with increased leptin sensitivity, the suppressor of cytokine signaling 3 (SOCS3) was ablated in LepR-expressing cells (LepR∆SOCS3 mice). LepR∆SOCS3 mice displayed reduced food intake, body adiposity and weight gain, as well as improved glucose tolerance and insulin sensitivity, and were protected against aging-induced leptin resistance. Surprisingly, a very high mortality rate was observed in aging LepR∆SOCS3 mice. LepR∆SOCS3 mice showed cardiomyocyte hypertrophy, increased myocardial fibrosis and reduced cardiovascular capacity. LepR∆SOCS3 mice exhibited impaired post-ischemic cardiac functional recovery and middle-aged LepR∆SOCS3 mice showed substantial arhythmic events during the post-ischemic reperfusion period. Finally, LepR∆SOCS3 mice exhibited fasting-induced hypoglycemia and impaired counterregulatory response to glucopenia associated with reduced gluconeogenesis. In conclusion, although increased sensitivity to leptin improved the energy and glucose homeostasis of aging LepR∆SOCS3 mice, major autonomic/neurovegetative dysfunctions compromised the health and longevity of these animals. Consequently, these potentially negative aspects need to be considered in the therapies that increase leptin sensitivity chronically.
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Ferrulli A, Terruzzi I, Senesi P, Succi M, Cannavaro D, Luzi L. Turning the clock forward: New pharmacological and non pharmacological targets for the treatment of obesity. Nutr Metab Cardiovasc Dis 2022; 32:1320-1334. [PMID: 35354547 DOI: 10.1016/j.numecd.2022.02.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 02/21/2022] [Accepted: 02/25/2022] [Indexed: 11/26/2022]
Abstract
AIMS Obesity and its main metabolic complication, type 2 diabetes, have attained the status of a global pandemic; there is need for novel strategies aimed at treating obesity and preventing the development of diabetes. A healthy diet and exercise are basic for treatment of obesity but often not enough. Pharmacotherapy can be helpful in maintaining compliance, ameliorating obesity-related health risks, and improving quality of life. In the last two decades, the knowledge of central and peripheral mechanisms underlying homeostatic and hedonic aspects of food intake has significantly increased. Dysregulation of one or more of these components could lead to obesity. DATA SYNTHESIS In order to better understand how potential innovative treatment options can affect obesity, homeostatic and reward mechanisms that regulate energy balance has been firstly illustrated. Then, an overview of potential therapeutic targets for obesity, distinguished according to the level of regulation of feeding behavior, has been provided. Moreover, several non-drug therapies have been recently tested in obesity, such as non-invasive neurostimulation: Transcranial Magnetic Stimulation or Transcranial Direct Current Stimulation. All of them are promising for obesity treatment and are almost devoid of side effects, constituting a potential resource for the prevention of metabolic diseases. CONCLUSIONS The plethora of current anti-obesity therapies creates the unique challenge for physicians to customize the intervention, according to the specific obesity characteristics and the intervention side effect profiles; moreover, it allows multimodal approaches addressed to treat obesity and metabolic adaptation with complementary mechanisms.
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Affiliation(s)
- Anna Ferrulli
- Department of Endocrinology, Nutrition and Metabolic Diseases, IRCCS MultiMedica, Sesto San Giovanni, MI, Italy; Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Ileana Terruzzi
- Department of Endocrinology, Nutrition and Metabolic Diseases, IRCCS MultiMedica, Sesto San Giovanni, MI, Italy; Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Pamela Senesi
- Department of Endocrinology, Nutrition and Metabolic Diseases, IRCCS MultiMedica, Sesto San Giovanni, MI, Italy; Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Massimiliano Succi
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Daniele Cannavaro
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Livio Luzi
- Department of Endocrinology, Nutrition and Metabolic Diseases, IRCCS MultiMedica, Sesto San Giovanni, MI, Italy; Department of Biomedical Sciences for Health, University of Milan, Milan, Italy.
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Brandt S, von Schnurbein J, Denzer C, Kratzer W, Wabitsch M. Lower Circulating Leptin Levels Are Related to Non-Alcoholic Fatty Liver Disease in Children With Obesity. Front Endocrinol (Lausanne) 2022; 13:881982. [PMID: 35677722 PMCID: PMC9169562 DOI: 10.3389/fendo.2022.881982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/04/2022] [Indexed: 11/13/2022] Open
Abstract
Background While for individuals with obesity an association between hyperleptinemia and an increased risk of non-alcoholic fatty liver disease (NAFLD) is assumed, a leptin deficiency is also related to the development of NAFLD early in life in ob/ob mice, in patients with leptin deficiency due to biallelic likely pathogenic variants in the leptin gene, and in patients with lipodystrophy. Objectives To investigate the association of circulating leptin levels in pre-pubertal children with obesity and steatosis hepatis. Methods The cross-sectional study consisted data of n=97 (nmale=76) pre-pubertal children (11.8 ± 1.5 years) with obesity (BMIz: 2.4 ± 0.4). Fasting concentrations of cardiometabolic parameters were measured: insulin, c-peptide, glucose, triglyceride, cholesterol, HDL, LDL, AST, ALT, GGT, leptin. Steatosis hepatis was diagnosed by an ultrasound examination (mild, moderate or severe). Patients were categorized into two groups: low z-score of circulating leptin levels (≤25th percentile) vs. normal z-score of circulating leptin levels. Results One-third of the children with obesity were diagnosed with steatosis hepatis (I°: 63.6%, II°/III°: 36.4%). Children with steatosis hepatis had significantly lower z-scores of circulating leptin levels compared to children with an unremarkable liver ultrasonography (-2.1 ± 0.8 vs. -0.7 ± 0.6). Z-scores of circulating leptin levels correlate negatively with degree of steatosis hepatis. Children with low z-scores of circulating leptin levels had significantly higher triglyceride, fasting insulin and c-peptide levels compared to children with normal z-scores of circulating leptin levels. Conclusion Prepubertal children with NAFLD and obesity and partial leptin deficiency might be defined as a clinical subgroup.
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Affiliation(s)
- Stephanie Brandt
- Center for Rare Endocrine Diseases, Division of Paediatric Endocrinology and Diabetes, Department of Paediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | - Julia von Schnurbein
- Center for Rare Endocrine Diseases, Division of Paediatric Endocrinology and Diabetes, Department of Paediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | - Christian Denzer
- Center for Rare Endocrine Diseases, Division of Paediatric Endocrinology and Diabetes, Department of Paediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | - Wolfgang Kratzer
- Department of Internal Medicine I, University Hospital Ulm, Ulm, Germany
| | - Martin Wabitsch
- Center for Rare Endocrine Diseases, Division of Paediatric Endocrinology and Diabetes, Department of Paediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
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Angelidi AM, Belanger MJ, Kokkinos A, Koliaki CC, Mantzoros CS. Novel Noninvasive Approaches to the Treatment of Obesity: From Pharmacotherapy to Gene Therapy. Endocr Rev 2022; 43:507-557. [PMID: 35552683 PMCID: PMC9113190 DOI: 10.1210/endrev/bnab034] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Indexed: 02/08/2023]
Abstract
Recent insights into the pathophysiologic underlying mechanisms of obesity have led to the discovery of several promising drug targets and novel therapeutic strategies to address the global obesity epidemic and its comorbidities. Current pharmacologic options for obesity management are largely limited in number and of modest efficacy/safety profile. Therefore, the need for safe and more efficacious new agents is urgent. Drugs that are currently under investigation modulate targets across a broad range of systems and tissues, including the central nervous system, gastrointestinal hormones, adipose tissue, kidney, liver, and skeletal muscle. Beyond pharmacotherapeutics, other potential antiobesity strategies are being explored, including novel drug delivery systems, vaccines, modulation of the gut microbiome, and gene therapy. The present review summarizes the pathophysiology of energy homeostasis and highlights pathways being explored in the effort to develop novel antiobesity medications and interventions but does not cover devices and bariatric methods. Emerging pharmacologic agents and alternative approaches targeting these pathways and relevant research in both animals and humans are presented in detail. Special emphasis is given to treatment options at the end of the development pipeline and closer to the clinic (ie, compounds that have a higher chance to be added to our therapeutic armamentarium in the near future). Ultimately, advancements in our understanding of the pathophysiology and interindividual variation of obesity may lead to multimodal and personalized approaches to obesity treatment that will result in safe, effective, and sustainable weight loss until the root causes of the problem are identified and addressed.
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Affiliation(s)
- Angeliki M Angelidi
- Section of Endocrinology, VA Boston Healthcare System, Harvard Medical School, Boston, MA, USA
- Department of Medicine Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Matthew J Belanger
- Department of Medicine Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Alexander Kokkinos
- First Department of Propaedeutic Medicine, Medical School, National and Kapodistrian University of Athens, Laiko General Hospital, Athens, Greece
| | - Chrysi C Koliaki
- First Department of Propaedeutic Medicine, Medical School, National and Kapodistrian University of Athens, Laiko General Hospital, Athens, Greece
| | - Christos S Mantzoros
- Section of Endocrinology, VA Boston Healthcare System, Harvard Medical School, Boston, MA, USA
- Department of Medicine Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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Wu O, Leng JH, Zhang X, Liu W, Yang FF, Zhang H, Li JJ, Zhang GZ, Lu X. Controversial culprit of leptin in obesity hypertension: clues from a case-control study with Chinese newly diagnosed adult early-onset obesity hypertensives. Clin Exp Hypertens 2022; 44:495-501. [PMID: 35531968 DOI: 10.1080/10641963.2022.2071920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Ou Wu
- Shulan International Medical College, Zhejiang Shuren University, Zhejiang, P.R. China
| | - Jian Hang Leng
- Department of Central Laboratory/Medical Examination Center of Hangzhou, The First People’s Hospital of Hangzhou, Zhejiang, P.R. China
| | - Xingyu Zhang
- Starzl Transplantation Institute, University of Pittsburgh Medical CenterThomas E. , Pittsburgh, PA, USA
| | - Wei Liu
- Joinstar Biomedical Technology Co., LTD, Hangzhou, P.R. China
| | - Fen Fang Yang
- Department of Central Laboratory/Medical Examination Center of Hangzhou, The First People’s Hospital of Hangzhou, Zhejiang, P.R. China
| | - Hu Zhang
- Department of Thoracic Surgery, Sir Run Run Shaw Hospital Affiliated with Medical College of Zhejiang University, Zhejiang, P.R. China
| | - Jia Jia Li
- Department of Central Laboratory, The First Affiliated Hospital of Anhui Medical University, Anhui, P.R. China
| | - Guo Zhong Zhang
- Microbiology Laboratory, Hangzhou Center for Disease Control and Prevention, Zhejiang, P.R. China
| | - Xi Lu
- Hangzhou Vocational and Technical College, Zhejiang, P.R. China
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Grasso P. Harnessing the Power of Leptin: The Biochemical Link Connecting Obesity, Diabetes, and Cognitive Decline. Front Aging Neurosci 2022; 14:861350. [PMID: 35527735 PMCID: PMC9072663 DOI: 10.3389/fnagi.2022.861350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/21/2022] [Indexed: 12/02/2022] Open
Abstract
In this review, the current understanding of leptin’s role in energy balance, glycemic regulation, and cognitive function is examined, and its involvement in maintaining the homeostatic “harmony” of these physiologies is explored. The effects of exercise on circulating leptin levels are summarized, and the results of clinical application of leptin to metabolic disease and neurologic dysfunction are reviewed. Finally, pre-clinical evidence is presented which suggests that synthetic peptide leptin mimetics may be useful in resolving not only the leptin resistance associated with common obesity and other elements of metabolic syndrome, but also the peripheral insulin resistance characterizing type 2 diabetes mellitus, and the central insulin resistance associated with certain neurologic deficits in humans.
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Affiliation(s)
- Patricia Grasso
- Department of Medicine, Albany Medical College, Albany, NY, United States
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, NY, United States
- *Correspondence: Patricia Grasso,
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Inamori KI. Regulation of Leptin Receptor Signaling by Gangliosides. TRENDS GLYCOSCI GLYC 2022. [DOI: 10.4052/tigg.2106.1j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Kei-ichiro Inamori
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University
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Inamori KI. Regulation of Leptin Receptor Signaling by Gangliosides. TRENDS GLYCOSCI GLYC 2022. [DOI: 10.4052/tigg.2106.1e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Kei-ichiro Inamori
- Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University
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Meral R, Malandrino N, Walter M, Neidert AH, Muniyappa R, Oral EA, Brown RJ. Endogenous Leptin Concentrations Poorly Predict Metreleptin Response in Patients With Partial Lipodystrophy. J Clin Endocrinol Metab 2022; 107:e1739-e1751. [PMID: 34677608 PMCID: PMC8947785 DOI: 10.1210/clinem/dgab760] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Indexed: 11/19/2022]
Abstract
CONTEXT Leptin replacement with metreleptin improves glycemia and hypertriglyceridemia in severely hypoleptinemic patients with generalized lipodystrophy (GLD), but its effects are variable in partially leptin-deficient patients with partial lipodystrophy (PLD). OBJECTIVE Compare 3 leptin assays (Study I); identify diagnostic performance of leptin assays to detect responders to metreleptin for each assay (Study II). DESIGN Study I: cross-sectional analysis of average bias between leptin assays. Study II: retrospective analysis of diagnostic accuracy of potential leptin cut points to detect clinical responders to metreleptin. SETTING National Institutes of Health; University of Michigan. PARTICIPANTS AND INTERVENTIONS Study I: Metreleptin-naïve patients with lipodystrophy (GLD, n = 33, PLD, n = 67) and healthy volunteers (n = 239). Study II: GLD (n = 66) and PLD (n = 84) patients treated with metreleptin for 12 months. OUTCOME MEASURES Leptin concentrations by Millipore radioimmunoassay (RIA), Millipore enzyme-linked immunosorbent assay (MELISA), and R&D Systems enzyme-linked immunosorbent assay (RDELISA). Response to metreleptin therapy was defined as either reduction ≥1.0% in A1c or ≥30% in serum triglycerides. RESULTS RDELISA measured 3.0 ± 9.5 ng/mL higher than RIA; MELISA measured 11.0 ± 17.8 and 14.0 ±19.2 less than RIA and RDELISA, respectively. Leptin by RIA, MELISA, and RDELISA modestly predicted metreleptin response in GLD + PLD [receiver operating characteristic (ROC) area under the curve (AUC) 0.74, 0.69, and 0.71, respectively; P < 0.01 for all] with lower predictive power in PLD (ROC AUC 0.63, 0.61 and 0.65, respectively; P > 0.05 for all). The only reproducible cut point identified on sensitivity analyses was RIA leptin 7.2 ng/mL (sensitivity 56%; specificity 78%). CONCLUSIONS Three common leptin assays are not interchangeable, and a reliable cut point to select responders to metreleptin was not identified.
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Affiliation(s)
- Rasimcan Meral
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, Bethesda, MD, USA
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Medical Biology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
- Department of General Surgery, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Noemi Malandrino
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, Bethesda, MD, USA
| | - Mary Walter
- Clinical Core Laboratory, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Adam H Neidert
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Ranganath Muniyappa
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, Bethesda, MD, USA
| | - Elif Arioglu Oral
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Rebecca J Brown
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, Bethesda, MD, USA
- Correspondence: Rebecca J. Brown, MD, MHSc, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Building 10-CRC, Room 6-5942, 10 Center Dr, Bethesda, MD 20892, USA.
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Maffei M, Giordano A. Leptin, the brain and energy homeostasis: From an apparently simple to a highly complex neuronal system. Rev Endocr Metab Disord 2022; 23:87-101. [PMID: 33822303 DOI: 10.1007/s11154-021-09636-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/11/2021] [Indexed: 12/14/2022]
Abstract
Leptin, produced and secreted by white adipose tissue in tight relationship with adipose mass, informs the brain about the status of the energy stores serving as the main peripheral signal for energy balance regulation through interaction with a multitude of highly interconnected neuronal populations. Most obese patients display resistance to the anorectic effect of the hormone. The present review unravels the multiple levels of complexity that trigger hypothalamic response to leptin with the objective of highlighting those critical hubs that, mainly in the hypothalamic arcuate nucleus, may undergo obesity-induced alterations and create an obstacle to leptin action. Several mechanisms underlying leptin resistance have been proposed, possibly representing useful targets to empower leptin effects. Among these, a special focus is herein dedicated to detail how leptin gains access into the brain and how neuronal plasticity may interfere with leptin function.
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Affiliation(s)
- Margherita Maffei
- Institute of Clinical Physiology, CNR, Via Moruzzi 1, 56124, Pisa, Italy.
- Obesity and Lipodystrophy Center, University Hospital of Pisa, Via Paradisa 2, 56124, Pisa, Italy.
| | - Antonio Giordano
- Department of Experimental and Clinical Medicine, Marche Polytechnic University, Via Tronto 10/A, 60020, Ancona, Italy.
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The complex interactions among serotonin, insulin, leptin, and glycolipid metabolic parameters in human obesity. CNS Spectr 2022; 27:99-108. [PMID: 32921339 DOI: 10.1017/s1092852920001820] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To provide evidence to the link between serotonin (5-HT), energy metabolism, and the human obese phenotype, the present study investigated the binding and function of the platelet 5-HT transporter (SERT), in relation to circulating insulin, leptin, and glycolipid metabolic parameters. METHODS Seventy-four drug-free subjects were recruited on the basis of divergent body mass index (BMIs) (16.5-54.8 Kg/m2). All subjects were tested for their blood glycolipid profile together with platelet [3H]-paroxetine ([3H]-Par) binding and [3H]-5-HT reuptake measurements from April 1st to June 30th, 2019. RESULTS The [3H]-Par Bmax (fmol/mg proteins) was progressively reduced with increasing BMIs (P < .001), without changes in affinity. Moreover, Bmax was negatively correlated with BMI, waist/hip circumferences (W/HC), triglycerides (TD), glucose, insulin, and leptin, while positively with high-density lipoprotein (HDL) cholesterol (P < .01). The reduction of 5-HT uptake rate (Vmax, pmol/min/109 platelets) among BMI groups was not statistically significant, but Vmax negatively correlated with leptin and uptake affinity values (P < .05). Besides, [3H]-Par affinity values positively correlated with glycemia and TD, while [3H]-5-HT reuptake affinity with glycemia only (P < .05). Finally, these correlations were specific of obese subjects, while, from multiple linear-regression analysis conducted on all subjects, insulin (P = .006) resulting negatively related to Bmax independently from BMI. CONCLUSIONS Present findings suggest the presence of a possible alteration of insulin/5-HT/leptin axis in obesity, differentially impinging the density, function, and/or affinity of the platelet SERT, as a result of complex appetite/reward-related interactions between the brain, gut, pancreatic islets, and adipose tissue. Furthermore, they support the foremost cooperation of peptides and 5-HT in maintaining energy homeostasis.
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The role of leptin and low testosterone in obesity. Int J Impot Res 2022; 34:704-713. [DOI: 10.1038/s41443-022-00534-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 01/21/2022] [Indexed: 12/29/2022]
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Suriagandhi V, Nachiappan V. Protective Effects of Melatonin against Obesity-Induced by Leptin Resistance. Behav Brain Res 2022; 417:113598. [PMID: 34563600 DOI: 10.1016/j.bbr.2021.113598] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 09/01/2021] [Accepted: 09/21/2021] [Indexed: 12/20/2022]
Abstract
Consumption of an exceedingly high-fat diet with irregular eating and sleeping habits is typical in the current sedentary lifestyle, leading to chronic diseases like obesity and diabetes mellitus. Leptin is a primary appetite-regulating hormone that binds to its receptors in the hypothalamic cell membrane and regulates downstream appetite-regulating neurons NPY/AgRp and POMC in the hypothalamus. Based on the fat content of the adipose tissue, leptin is secreted, and excess accumulation of fat in adipose tissue stimulates the abnormal secretion of leptin. The secreted leptin circulating in the bloodstream uses its transporters to cross the blood-brain barrier (BBB) and reach the CSF. There is a saturation limit for leptin bound to its transporters to cross the BBB, and increased leptin secretion in adipose tissue has a defect in its transport across the BBB. Leptin resistance is due to excess leptin, a saturation of its transporters, and deficiency in either the receptor level or signalling in the hypothalamus. Leptin resistance leads to obesity due to excess food intake and less energy expenditure. Normal leptin secretion follows a rhythm, and alteration in the lifestyle leads to hormonal imbalances and increases ROS generation leading to oxidative stress. The sleep disturbance causes obesity with increased lipid accumulation in adipose tissue. Melatonin is the master regulator of the sleep-wake cycle secreted by the pineal gland during the night. It is a potent antioxidant with anti-inflammatory properties. Melatonin is secreted in a pattern called the circadian rhythm in humans as well. Research indicates that melatonin plays a vital role in hormonal regulation and energy metabolism, including leptin signalling and secretion. Studying the role of melatonin in leptin regulation will help us combat the pathologies of obesity caused by leptin resistance.
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Affiliation(s)
- Vennila Suriagandhi
- Biomembrane Lab, Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli 620024, Tamilnadu, India
| | - Vasanthi Nachiappan
- Biomembrane Lab, Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli 620024, Tamilnadu, India.
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