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McMorrow HE, Lorch CM, Hayes NW, Fleps SW, Frydman JA, Xia JL, Samms RJ, Beutler LR. Incretin hormones and pharmacomimetics rapidly inhibit AgRP neuron activity to suppress appetite. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.18.585583. [PMID: 38562891 PMCID: PMC10983981 DOI: 10.1101/2024.03.18.585583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Analogs of the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) have become mainstays of obesity and diabetes management. However, both the physiologic role of incretin hormones in the control of appetite and the pharmacologic mechanisms by which incretin-mimetic drugs suppress caloric intake remain incompletely understood. Hunger-promoting AgRP-expressing neurons are an important hypothalamic population that regulates food intake. Therefore, we set out to determine how incretins analogs affect their activity in vivo. Using fiber photometry, we observed that both GIP receptor (GIPR) and GLP-1 receptor (GLP-1R) agonism acutely inhibit AgRP neuron activity in fasted mice and reduce the response of AgRP neurons to food. Moreover, optogenetic stimulation of AgRP neurons partially attenuated incretin-induced feeding suppression, suggesting that AgRP neuron inhibition is necessary for the full appetite-suppressing effects of incretin-based therapeutics. Finally, we found that GIP but not GLP-1 is necessary for nutrient-mediated AgRP neuron inhibition, representing a novel physiologic role for GIP in maintaining energy balance. Taken together, these findings reveal neural mechanisms underlying the efficacy of incretin-mimetic obesity therapies. Understanding these drugs' mechanisms of action is crucial for the development of next-generation obesity pharmacotherapies with an improved therapeutic profile.
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Affiliation(s)
- Hayley E McMorrow
- Department of Medicine, Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University, Chicago, IL 60611, USA
- Interdepartmental Neuroscience Graduate Program, Northwestern University, Chicago, IL, USA
| | - Carolyn M Lorch
- Department of Medicine, Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University, Chicago, IL 60611, USA
- Driskill Graduate Program in Life Sciences, Northwestern University, Chicago, IL, USA
| | - Nikolas W Hayes
- Department of Medicine, Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University, Chicago, IL 60611, USA
- Interdepartmental Neuroscience Graduate Program, Northwestern University, Chicago, IL, USA
| | - Stefan W Fleps
- Department of Medicine, Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University, Chicago, IL 60611, USA
- Department of Neuroscience, Northwestern University, Chicago, IL, USA
| | - Joshua A Frydman
- Department of Medicine, Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Jessica L Xia
- Department of Medicine, Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Ricardo J Samms
- Diabetes, Obesity and Complications Therapeutic Area, Eli Lilly, Indianapolis, IN, USA
| | - Lisa R Beutler
- Department of Medicine, Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University, Chicago, IL 60611, USA
- Lead contact
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2
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Ruck L, Wiegand S, Kühnen P. Relevance and consequence of chronic inflammation for obesity development. Mol Cell Pediatr 2023; 10:16. [PMID: 37957462 PMCID: PMC10643747 DOI: 10.1186/s40348-023-00170-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 10/26/2023] [Indexed: 11/15/2023] Open
Abstract
BACKGROUND Increasing prevalence of morbid obesity accompanied by comorbidities like type 2 diabetes mellitus (T2DM) led to a demand for improving therapeutic strategies and pharmacological intervention options. Apart from genetics, inflammation processes have been hypothesized to be of importance for the development of obesity and related aspects like insulin resistance. MAIN TEXT Within this review, we provide an overview of the intricate interplay between chronic inflammation of the adipose tissue and the hypothalamus and the development of obesity. Further understanding of this relationship might improve the understanding of the underlying mechanism and may be of relevance for the establishment of new treatment strategies.
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Affiliation(s)
- Lisa Ruck
- Klinik Für Pädiatrische Endokrinologie und Diabetologie, Charité Universitätsmedizin, Berlin, Germany.
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, BIH Biomedical Innovation Academy, BIH Charité Junior Clinician Scientist Program, Charitéplatz 1, 10117, Berlin, Germany.
| | - Susanna Wiegand
- Abteilung Interdisziplinär, Sozial-Pädiatrisches Zentrum, Charité Universitätsmedizin, Berlin, Germany
| | - Peter Kühnen
- Klinik Für Pädiatrische Endokrinologie und Diabetologie, Charité Universitätsmedizin, Berlin, Germany
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3
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Khan D, Sridhar A, Flatt PR, Moffett RC. Disturbed ovarian morphology, oestrous cycling and fertility of high fat fed rats are linked to alterations of incretin receptor expression. Reprod Biol 2023; 23:100784. [PMID: 37343433 DOI: 10.1016/j.repbio.2023.100784] [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: 04/05/2023] [Revised: 06/05/2023] [Accepted: 06/08/2023] [Indexed: 06/23/2023]
Abstract
Obesity is a major cause of infertility in females with a direct correlation between energy intake and reproductive dysfunction. To explore underlying mechanisms, disturbances in reproductive health and incretin/reproductive hormone receptor expression were studied in female Wistar rats fed a high-fat-diet for 20-weeks. Metabolic parameters and ovarian/adrenal gene expression were monitored along with estrous cycling and fertility upon mating. High-fat-feeding significantly increased body weight, plasma insulin and HOMA-IR, indicative of obesity and insulin resistance. Estrous cycles were prolonged compared to normal chow-fed rats, with 50 % having an average cycle length ≥ 7days. Reproductive outcomes revealed high-fat-diet reduced litter size by 48 %, with 16 % rats unable to achieve pregnancy. Furthermore, 80 % of the high-fat group took > 35 days to become pregnant compared to 33 % fed a normal-diet. Also, 35 % of pups born to high-fat-fed rats were eaten by mothers or born dead which was not observed with control rats. These changes were associated with downregulation of Amh, Npy2R and GcgR gene expression in ovaries with upregulation of InsR and Glp-1R genes. In adrenals, Glp-1R, GipR, Npy2R, InsR, GcgR, GshR and Esr-1 genes were upregulated. Histological analysis of high-fat-diet ovaries and adrenals revealed changes in morphology with significantly increased number of cysts and reduced adrenal capsule thickness. Circulating levels of insulin, testosterone and progesterone was significantly higher in high-fat group with reduced FSH levels in plasma. These data demonstrate that high-fat feeding disrupts female reproductive function and suggest important interactions between gut and reproductive hormones in ovaries and adrenals which merit further investigation.
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Affiliation(s)
- Dawood Khan
- Biomedical Sciences Research Institute, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom.
| | - Ananyaa Sridhar
- Biomedical Sciences Research Institute, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - Peter R Flatt
- Biomedical Sciences Research Institute, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - R Charlotte Moffett
- Biomedical Sciences Research Institute, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
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4
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Batiha GES, Al-kuraishy HM, Al-Gareeb AI, Ashour NA, Negm WA. Potential role of tirzepatide towards Covid-19 infection in diabetic patients: a perspective approach. Inflammopharmacology 2023; 31:1683-1693. [PMID: 37208555 PMCID: PMC10198595 DOI: 10.1007/s10787-023-01239-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 04/21/2023] [Indexed: 05/21/2023]
Abstract
In Covid-19, variations in fasting blood glucose are considered a distinct risk element for a bad prognosis and outcome in Covid-19 patients. Tirazepatide (TZT), a dual glucagon-like peptide-1 (GLP-1)and glucose-dependent insulinotropic polypeptide (GIP) receptor agonist may be effective in managing Covid-19-induced hyperglycemia in diabetic and non-diabetic patients. The beneficial effect of TZT in T2DM and obesity is related to direct activation of GIP and GLP-1 receptors with subsequent improvement of insulin sensitivity and reduction of body weight. TZT improves endothelial dysfunction (ED) and associated inflammatory changes through modulation of glucose homeostasis, insulin sensitivity, and pro-inflammatory biomarkers release. TZT, through activation of the GLP-1 receptor, may produce beneficial effects against Covid-19 severity since GLP-1 receptor agonists (GLP-1RAs) have anti-inflammatory and pulmoprotective implications in Covid-19. Therefore, GLP-1RAs could effectively treat severely affected Covid-19 diabetic and non-diabetic patients. Notably, using GLP-1RAs in T2DM patients prevents glucose variability, a common finding in Covid-19 patients. Therefore, GLP-1RAs like TZT could be a therapeutic strategy in T2DM patients with Covid-19 to prevent glucose variability-induced complications. In Covid-19, the inflammatory signaling pathways are highly activated, resulting in hyperinflammation. GLP-1RAs reduce inflammatory biomarkers like IL-6, CRP, and ferritin in Covid-19 patients. Therefore, GLP-1RAs like TZ may be effective in Covid-19 patients by reducing the inflammatory burden. The anti-obesogenic effect of TZT may reduce Covid-19 severity by ameliorating body weight and adiposity. Furthermore, Covid-19 may induce substantial alterations in gut microbiota. GLP-1RA preserves gut microbiota and prevents intestinal dysbiosis. Herein, TZT, like other GLP-1RA, may attenuate Covid-19-induced gut microbiota alterations and, by this mechanism, may mitigate intestinal inflammation and systemic complications in Covid-19 patients with either T2DM or obesity. As opposed to that, glucose-dependent insulinotropic polypeptide (GIP) was reduced in obese and T2DM patients. However, activation of GIP-1R by TZT in T2DM patients improves glucose homeostasis. Thus, TZT, through activation of both GIP and GLP-1, may reduce obesity-mediated inflammation. In Covid-19, GIP response to the meal is impaired, leading to postprandial hyperglycemia and abnormal glucose homeostasis. Therefore, using TZT in severely affected Covid-19 patients may prevent the development of glucose variability and hyperglycemia-induced oxidative stress. Moreover, exaggerated inflammatory disorders in Covid-19 due to the release of pro-inflammatory cytokines like IL-1β, IL-6, and TNF-α may lead to systemic inflammation and cytokine storm development. Besides, GIP-1 inhibits expression of IL-1β, IL-6, MCP-1, chemokines and TNF-α. Therefore, using GIP-1RA like TZT may inhibit the onset of inflammatory disorders in severely affected Covid-19 patients. In conclusion, TZT, through activation of GLP-1 and GIP receptors, may prevent SARS-CoV-2-induced hyperinflammation and glucose variability in diabetic and non-diabetic patients.
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Affiliation(s)
- Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, AlBeheira, P.O. Box 22511, Damanhour, Egypt
| | - Hayder M. Al-kuraishy
- Department of Clinical Pharmacology and Medicine, College of Medicine, AL-Mustansiriyia University, P.O. Box 14132, Baghdad, Iraq
| | - Ali I. Al-Gareeb
- Department of Clinical Pharmacology and Medicine, College of Medicine, AL-Mustansiriyia University, P.O. Box 14132, Baghdad, Iraq
| | - Nada A. Ashour
- Department of Clinical Pharmacology and Toxicology, Faculty of Pharmacy, Tanta University, Tanta, 31527 Egypt
| | - Walaa A. Negm
- Department of Pharmacognosy, Faculty of Pharmacy, Tanta University, Tanta, 31527, Egypt
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5
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Chakhtoura M, Haber R, Ghezzawi M, Rhayem C, Tcheroyan R, Mantzoros CS. Pharmacotherapy of obesity: an update on the available medications and drugs under investigation. EClinicalMedicine 2023; 58:101882. [PMID: 36992862 PMCID: PMC10041469 DOI: 10.1016/j.eclinm.2023.101882] [Citation(s) in RCA: 76] [Impact Index Per Article: 76.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 02/06/2023] [Accepted: 02/07/2023] [Indexed: 03/31/2023] Open
Abstract
Obesity is an epidemic and a public health threat. Medical weight management remains one of the options for the treatment of excess weight and recent advances have revolutionized how we treat, and more importantly how we will be treating obesity in the near future. Metreleptin and Setmelanotide are currently indicated for rare obesity syndromes, and 5 other medications (orlistat, phentermine/topiramate, naltrexone/bupropion, liraglutide, semaglutide) are approved for non-syndromic obesity. Tirzepatide is about to be approved, and other drugs, with exciting novel mechanisms of action primarily based on incretins, are currently being investigated in different phases of clinical trials. The majority of these compounds act centrally, to reduce appetite and increase satiety, and secondarily, in the gastrointestinal tract to slow gastric emptying. All anti-obesity medications improve weight and metabolic parameters, with variable potency and effects depending on the specific drug. The currently available data do not support a reduction in hard cardiovascular outcomes, but it is almost certain that such data are forthcoming in the very near future. The choice of the anti-obesity medication needs to take into consideration the patient's clinical and biochemical profile, co-morbidities, and drug contra-indications, as well as expected degree of weight loss and improvements in cardio-renal and metabolic risk. It also remains to be seen whether precision medicine may offer personalized solutions to individuals with obesity, and whether it may represent the future of medical weight management along with the development of novel, very potent, anti-obesity medications currently in the pipeline. Funding None.
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Affiliation(s)
- Marlene Chakhtoura
- Division of Endocrinology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Rachelle Haber
- Division of Endocrinology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Malak Ghezzawi
- Division of Endocrinology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Caline Rhayem
- Division of Endocrinology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Raya Tcheroyan
- Faculty of Medicine and Medical Center, American University of Beirut, Beirut, Lebanon
| | - Christos S. Mantzoros
- Beth Israel Deaconess Medical Center and Boston VA Healthcare System, Harvard Medical School, Boston, MA, USA
- Corresponding author. Harvard Medical School, AN-249, 330 Brookline Ave, Boston, MA 02215, USA.
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Hammoud R, Drucker DJ. Beyond the pancreas: contrasting cardiometabolic actions of GIP and GLP1. Nat Rev Endocrinol 2023; 19:201-216. [PMID: 36509857 DOI: 10.1038/s41574-022-00783-3] [Citation(s) in RCA: 54] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/17/2022] [Indexed: 12/14/2022]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP1) exhibit incretin activity, meaning that they potentiate glucose-dependent insulin secretion. The emergence of GIP receptor (GIPR)-GLP1 receptor (GLP1R) co-agonists has fostered growing interest in the actions of GIP and GLP1 in metabolically relevant tissues. Here, we update concepts of how these hormones act beyond the pancreas. The actions of GIP and GLP1 on liver, muscle and adipose tissue, in the control of glucose and lipid homeostasis, are discussed in the context of plausible mechanisms of action. Both the GIPR and GLP1R are expressed in the central nervous system, wherein receptor activation produces anorectic effects enabling weight loss. In preclinical studies, GIP and GLP1 reduce atherosclerosis. Furthermore, GIPR and GLP1R are expressed within the heart and immune system, and GLP1R within the kidney, revealing putative mechanisms linking GIP and GLP1R agonism to cardiorenal protection. We interpret the clinical and mechanistic data obtained for different agents that enable weight loss and glucose control for the treatment of obesity and type 2 diabetes mellitus, respectively, by activating or blocking GIPR signalling, including the GIPR-GLP1R co-agonist tirzepatide, as well as the GIPR antagonist-GLP1R agonist AMG-133. Collectively, we update translational concepts of GIP and GLP1 action, while highlighting gaps, areas of uncertainty and controversies meriting ongoing investigation.
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Affiliation(s)
- Rola Hammoud
- Department of Medicine, Lunenfeld-Tanenbaum Research Institute, Mt Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Daniel J Drucker
- Department of Medicine, Lunenfeld-Tanenbaum Research Institute, Mt Sinai Hospital, University of Toronto, Toronto, Ontario, Canada.
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7
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Transcriptomic Classification of Pituitary Neuroendocrine Tumors Causing Acromegaly. Cells 2022; 11:cells11233846. [PMID: 36497102 PMCID: PMC9738119 DOI: 10.3390/cells11233846] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/22/2022] [Accepted: 11/25/2022] [Indexed: 12/03/2022] Open
Abstract
Acromegaly results from growth hormone hypersecretion, predominantly caused by a somatotroph pituitary neuroendocrine tumor (PitNET). Acromegaly-causing tumors are histologically diverse. Our aim was to determine transcriptomic profiles of various somatotroph PitNETs and to evaluate clinical implication of differential gene expression. A total of 48 tumors were subjected to RNA sequencing, while expression of selected genes was assessed in 134 tumors with qRT-PCR. Whole-transcriptome analysis revealed three transcriptomic groups of somatotroph PitNETs. They differ in expression of numerous genes including those involved in growth hormone secretion and known prognostic genes. Transcriptomic subgroups can be distinguished by determining the expression of marker genes. Analysis of the entire cohort of patients confirmed differences between molecular subtypes of tumors. Transcriptomic group 1 includes ~20% of acromegaly patients with GNAS mutations-negative, mainly densely granulated tumors that co-express GIPR and NR5A1 (SF-1). SF-1 expression was verified with immunohistochemistry. Transcriptomic group 2 tumors are the most common (46%) and include mainly GNAS-mutated, densely granulated somatotroph and mixed PitNETs. They have a smaller size and express favorable prognosis-related genes. Transcriptomic group 3 includes predominantly sparsely granulated somatotroph PitNETs with low GNAS mutations frequency causing ~35% of acromegaly. Ghrelin signaling is implicated in their pathogenesis. They have an unfavorable gene expression profile and higher invasive growth rate.
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8
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El Meouchy P, Wahoud M, Allam S, Chedid R, Karam W, Karam S. Hypertension Related to Obesity: Pathogenesis, Characteristics and Factors for Control. Int J Mol Sci 2022; 23:ijms232012305. [PMID: 36293177 PMCID: PMC9604511 DOI: 10.3390/ijms232012305] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/01/2022] [Accepted: 10/07/2022] [Indexed: 11/16/2022] Open
Abstract
The World Health Organization (WHO) refers to obesity as abnormal or excessive fat accumulation that presents a health risk. Obesity was first designated as a disease in 2012 and since then the cost and the burden of the disease have witnessed a worrisome increase. Obesity and hypertension are closely interrelated as abdominal obesity interferes with the endocrine and immune systems and carries a greater risk for insulin resistance, diabetes, hypertension, and cardiovascular disease. Many factors are at the interplay between obesity and hypertension. They include hemodynamic alterations, oxidative stress, renal injury, hyperinsulinemia, and insulin resistance, sleep apnea syndrome and the leptin-melanocortin pathway. Genetics, epigenetics, and mitochondrial factors also play a major role. The measurement of blood pressure in obese patients requires an adapted cuff and the search for other secondary causes is necessary at higher thresholds than the general population. Lifestyle modifications such as diet and exercise are often not enough to control obesity, and so far, bariatric surgery constitutes the most reliable method to achieve weight loss. Nonetheless, the emergence of new agents such as Semaglutide and Tirzepatide offers promising alternatives. Finally, several molecular pathways are actively being explored, and they should significantly extend the treatment options available.
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Affiliation(s)
- Paul El Meouchy
- Department of Internal Medicine, MedStar Health, Baltimore, MD 21218, USA
| | - Mohamad Wahoud
- Department of Internal Medicine, Tufts Medical Center, Boston, MA 02111, USA
| | - Sabine Allam
- Faculty of Medicine and Medical Sciences, University of Balamand, El Koura P.O. Box 100, Lebanon
| | - Roy Chedid
- College of Osteopathic Medicine, William Carey University, Hattiesburg, MS 39401, USA
| | - Wissam Karam
- Department of Internal Medicine, University of Kansas School of Medicine, Wichita, KS 67214, USA
| | - Sabine Karam
- Division of Nephrology and Hypertension, University of Minnesota, Minneapolis, MN 55414, USA
- Correspondence:
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9
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Tsai SF, Hung HC, Shih MMC, Chang FC, Chung BC, Wang CY, Lin YL, Kuo YM. High-fat diet-induced increases in glucocorticoids contribute to the development of non-alcoholic fatty liver disease in mice. FASEB J 2021; 36:e22130. [PMID: 34959259 DOI: 10.1096/fj.202101570r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 12/08/2021] [Accepted: 12/16/2021] [Indexed: 12/19/2022]
Abstract
This study aimed to investigate the causal relationship between chronic ingestion of a high-fat diet (HFD)-induced secretion of glucocorticoids (GCs) and the development of non-alcoholic fatty liver disease (NAFLD). We have produced a strain of transgenic mice (termed L/L mice) that have normal levels of circulating corticosterone (CORT), the major type of GCs in rodents, but unlike wild-type (WT) mice, their circulating CORT was not affected by HFD. Compared to WT mice, 12-week HFD-induced fatty liver was less pronounced with higher plasma levels of triglycerides in L/L mice. These changes were reversed by CORT supplement to L/L mice. By analyzing a sort of lipid metabolism-related proteins, we found that expressions of the hepatic cluster of differentiation 36 (CD36) were upregulated by HFD-induced CORT and involved in CORT-mediated fatty liver. Dexamethasone, an agonist of the glucocorticoid receptor (GR), upregulated expressions of CD36 in HepG2 hepatocytes and facilitated lipid accumulation in the cells. In conclusion, the fat ingestion-induced release of CORT contributes to NAFLD. This study highlights the pathogenic role of CORT-mediated upregulation of hepatic CD 36 in diet-induced NAFLD.
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Affiliation(s)
- Sheng-Feng Tsai
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hao-Chang Hung
- Division of Endocrinology and Metabolism, Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Division of Endocrinology and Metabolism, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | | | - Fu-Chuan Chang
- Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Bon-Chu Chung
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Chia-Yih Wang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Ling Lin
- Division of Gastroenterology, Department of Internal Medicine, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chiayi, Taiwan
| | - Yu-Min Kuo
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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10
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Abstract
Glucose-dependent insulinotropic polypeptide (GIP) (also known as gastric inhibitory polypeptide) is a hormone produced in the upper gut and secreted to the circulation in response to the ingestion of foods, especially fatty foods. Growing evidence supports the physiological and pharmacological relevance of GIP in obesity. In an obesity setting, inhibition of endogenous GIP or its receptor leads to decreased energy intake, increased energy expenditure, or both, eventually causing weight loss. Further, supraphysiological dosing of exogenous long-lasting GIP agonists alters energy balance and has a marked antiobesity effect. This remarkable yet paradoxical antiobesity effect is suggested to occur primarily via the brain. The brain is capable of regulating both energy intake and expenditure and plays a critical role in human obesity. In addition, the GIP receptor is widely distributed throughout the brain, including areas responsible for energy homeostasis. Recent studies have uncovered previously underappreciated roles of the GIP receptor in the brain in the context of obesity. This article highlights how the GIP receptor expressed by the brain impacts obesity-related pathogenesis.
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Affiliation(s)
- Makoto Fukuda
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX
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11
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Neuroendocrine control of appetite and metabolism. Exp Mol Med 2021; 53:505-516. [PMID: 33837263 PMCID: PMC8102538 DOI: 10.1038/s12276-021-00597-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 02/11/2021] [Accepted: 02/17/2021] [Indexed: 02/02/2023] Open
Abstract
Body homeostasis is predominantly controlled by hormones secreted by endocrine organs. The central nervous system contains several important endocrine structures, including the hypothalamic-pituitary axis. Conventionally, neurohormones released by the hypothalamus and the pituitary gland (hypophysis) have received much attention owing to the unique functions of the end hormones released by their target peripheral organs (e.g., glucocorticoids released by the adrenal glands). Recent advances in mouse genetics have revealed several important metabolic functions of hypothalamic neurohormone-expressing cells, many of which are not readily explained by the action of the corresponding classical downstream hormones. Notably, the newly identified functions are better explained by the action of conventional neurotransmitters (e.g., glutamate and GABA) that constitute a neuronal circuit. In this review, we discuss the regulation of appetite and metabolism by hypothalamic neurohormone-expressing cells, with a focus on the distinct contributions of neurohormones and neurotransmitters released by these neurons.
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12
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Campbell JE. Targeting the GIPR for obesity: To agonize or antagonize? Potential mechanisms. Mol Metab 2020; 46:101139. [PMID: 33290902 PMCID: PMC8085569 DOI: 10.1016/j.molmet.2020.101139] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 11/24/2020] [Accepted: 12/02/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Glucose-dependent insulinotropic peptide (GIP) is one of two incretin hormones that communicate nutrient intake with systemic metabolism. Although GIP was the first incretin hormone to be discovered, the understanding of GIP's biology was quickly outpaced by research focusing on the other incretin hormone, glucagon-like peptide 1 (GLP-1). Early work on GIP produced the theory that GIP is obesogenic, limiting interest in developing GIPR agonists to treat type 2 diabetes. A resurgence of GIP research has occurred in the last five years, reinvigorating interest in this peptide. Two independent approaches have emerged for treating obesity, one promoting GIPR agonism and the other antagonism. In this report, evidence supporting both cases is discussed and hypotheses are presented to reconcile this apparent paradox. SCOPE OF THE REVIEW This review presents evidence to support targeting GIPR to reduce obesity. Most of the focus is on the effect of singly targeting the GIPR using both a gain- and loss-of-function approach, with additional sections that discuss co-targeting of the GIPR and GLP-1R. MAJOR CONCLUSIONS There is substantial evidence to support that GIPR agonism and antagonism can positively impact body weight. The long-standing theory that GIP drives weight gain is exclusively derived from loss-of-function studies, with no evidence to support that GIPR agonisms increases adiposity or body weight. There is insufficient evidence to reconcile the paradoxical observations that both GIPR agonism and antagonism can reduce body weight; however, two independent hypotheses centered on GIPR antagonism are presented based on new data in an effort to address this question. The first discusses the compensatory relationship between incretin receptors and how antagonism of the GIPR may enhance GLP-1R activity. The second discusses how chronic GIPR agonism may produce desensitization and ultimately loss of GIPR activity that mimics antagonism. Overall, it is clear that a deeper understanding of GIP biology is required to understand how modulating this system impacts metabolic homeostasis.
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Affiliation(s)
- Jonathan E Campbell
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA; Department of Medicine, Division of Endocrinology, Duke University, Durham, NC, USA; Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, USA.
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Killion EA, Chen M, Falsey JR, Sivits G, Hager T, Atangan L, Helmering J, Lee J, Li H, Wu B, Cheng Y, Véniant MM, Lloyd DJ. Chronic glucose-dependent insulinotropic polypeptide receptor (GIPR) agonism desensitizes adipocyte GIPR activity mimicking functional GIPR antagonism. Nat Commun 2020; 11:4981. [PMID: 33020469 PMCID: PMC7536395 DOI: 10.1038/s41467-020-18751-8] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 09/09/2020] [Indexed: 12/30/2022] Open
Abstract
Antagonism or agonism of the glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) prevents weight gain and leads to dramatic weight loss in combination with glucagon-like peptide-1 receptor agonists in preclinical models. Based on the genetic evidence supporting GIPR antagonism, we previously developed a mouse anti-murine GIPR antibody (muGIPR-Ab) that protected diet-induced obese (DIO) mice against body weight gain and improved multiple metabolic parameters. This work reconciles the similar preclinical body weight effects of GIPR antagonists and agonists in vivo, and here we show that chronic GIPR agonism desensitizes GIPR activity in primary adipocytes, both differentiated in vitro and adipose tissue in vivo, and functions like a GIPR antagonist. Additionally, GIPR activity in adipocytes is partially responsible for muGIPR-Ab to prevent weight gain in DIO mice, demonstrating a role of adipocyte GIPR in the regulation of adiposity in vivo.
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Affiliation(s)
- Elizabeth A Killion
- Amgen Research, Department of Cardiometabolic Disorders, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - Michelle Chen
- Amgen Research, Department of Cardiometabolic Disorders, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - James R Falsey
- Amgen Research, Department of Selection and Modality Engineering, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - Glenn Sivits
- Amgen Research, Department of Cardiometabolic Disorders, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - Todd Hager
- Amgen Research, Department of Translational Safety & Bioanalytical Sciences, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - Larissa Atangan
- Amgen Research, Department of Cardiometabolic Disorders, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - Joan Helmering
- Amgen Research, Department of Cardiometabolic Disorders, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - Jae Lee
- Amgen Research, Department of Cardiometabolic Disorders, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - Hongyan Li
- Amgen Research, Department of Translational Safety & Bioanalytical Sciences, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - Bin Wu
- Amgen Research, Department of Selection and Modality Engineering, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - Yuan Cheng
- Amgen Research, Department of Selection and Modality Engineering, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - Murielle M Véniant
- Amgen Research, Department of Cardiometabolic Disorders, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA
| | - David J Lloyd
- Amgen Research, Department of Cardiometabolic Disorders, Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, 91320, USA.
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14
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Fu Y, Kaneko K, Lin HY, Mo Q, Xu Y, Suganami T, Ravn P, Fukuda M. Gut Hormone GIP Induces Inflammation and Insulin Resistance in the Hypothalamus. Endocrinology 2020; 161:5865317. [PMID: 32603429 PMCID: PMC7410368 DOI: 10.1210/endocr/bqaa102] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 06/24/2020] [Indexed: 02/08/2023]
Abstract
The hypothalamus plays a critical role in controlling energy balance. High-fat diet (HFD) feeding increases the gene expression of proinflammatory mediators and decreases insulin actions in the hypothalamus. Here, we show that a gut-derived hormone, glucose-dependent insulinotropic polypeptide (GIP), whose levels are elevated during diet-induced obesity, promotes and mediates hypothalamic inflammation and insulin resistance during HFD-induced obesity. Unbiased ribonucleic acid sequencing of GIP-stimulated hypothalami revealed that hypothalamic pathways most affected by intracerebroventricular (ICV) GIP stimulation were related to inflammatory-related responses. Subsequent analysis demonstrated that GIP administered either peripherally or centrally, increased proinflammatory-related factors such as Il-6 and Socs3 in the hypothalamus, but not in the cortex of C57BL/6J male mice. Consistently, hypothalamic activation of IκB kinase-β inflammatory signaling was induced by ICV GIP. Further, hypothalamic levels of proinflammatory cytokines and Socs3 were significantly reduced by an antagonistic GIP receptor (GIPR) antibody and by GIPR deficiency. Additionally, centrally administered GIP reduced anorectic actions of insulin in the brain and diminished insulin-induced phosphorylation of Protein kinase B and Glycogen synthase kinase 3β in the hypothalamus. Collectively, these findings reveal a previously unrecognized role for brain GIP signaling in diet-induced inflammation and insulin resistance in the hypothalamus.
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Affiliation(s)
- Yukiko Fu
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
- Department of Molecular Medicine and Metabolism, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Kentaro Kaneko
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Hsiao-Yun Lin
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Qianxing Mo
- Dan L Duncan Cancer Center and Center for Cell Gene & Therapy, Baylor College of Medicine, Houston, Texas
- Present address: Department of Biostatistics & Bioinformatics, H. Lee Moffitt Cancer Center & Research Institute, Tampa, Florida 33612
| | - Yong Xu
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas
| | - Takayoshi Suganami
- Department of Molecular Medicine and Metabolism, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Peter Ravn
- AstraZeneca, R&D BioPharmaceuticals Unit, Department of Antibody Discovery and Protein Engineering, Cambridge, UK
| | - Makoto Fukuda
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
- Correspondence: Makoto Fukuda, Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA. E-mail:
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15
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Adriaenssens AE, Gribble FM, Reimann F. The glucose-dependent insulinotropic polypeptide signaling axis in the central nervous system. Peptides 2020; 125:170194. [PMID: 31697967 DOI: 10.1016/j.peptides.2019.170194] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 10/31/2019] [Accepted: 10/31/2019] [Indexed: 12/25/2022]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) is an incretin hormone released from the epithelium of the upper small intestine. While GIP shares common actions on the pancreatic beta cell with glucagon-like peptide-1 (GLP-1), unlike GLP-1, GIP presents a complex target for the development of diabetes and obesity therapies due to its extra-pancreatic effects on fat mass. Recent pharmacological developments, however, have provided insight into a previously unrecognized role for GIP receptor (GIPR) signaling in regulating appetite. Additionally, GIP-based therapeutics have demonstrated promising neuroprotective properties. Together these observations identify an important central component of the GIP/GIPR signaling axis, and have triggered a resurgence of research interest into the central actions of GIP. In this review, we discuss what is currently known about where GIP may act in the central nervous system (CNS), the characteristics of its target cell populations, and the physiological effects of manipulating the activity Gipr-expressing cells in the brain.
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Affiliation(s)
- A E Adriaenssens
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK
| | - F M Gribble
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK.
| | - F Reimann
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK.
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16
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Regazzo D, Barbot M, Scaroni C, Albiger N, Occhi G. The pathogenic role of the GIP/GIPR axis in human endocrine tumors: emerging clinical mechanisms beyond diabetes. Rev Endocr Metab Disord 2020; 21:165-183. [PMID: 31933128 DOI: 10.1007/s11154-019-09536-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The glucose-dependent insulinotropic polypeptide (GIP) is an incretin hormone produced in the gastrointestinal tract in response to nutrients. GIP has a variety of effects on different systems, including the potentiation of insulin secretion from pancreatic β-cells after food intake (i.e. incretin effect), which is probably the most important. GIP effects are mediated by the GIP receptor (GIPR), a G protein-coupled receptor expressed in several tissues, including islet β-cells, adipocytes, bone cells, and brain. As well as its involvement in metabolic disorders (e.g. it contributes to the impaired postprandial insulin secretion in type 2 diabetes (T2DM), and to the pathogenesis of obesity and associated insulin resistance), an inappropriate GIP/GIPR axis activation of potential diagnostic and prognostic value has been reported in several endocrine tumors in recent years. The ectopic GIPR expression seen in patients with overt Cushing syndrome and primary bilateral macronodular adrenal hyperplasia or unilateral cortisol-producing adenoma has been associated with an inverse rhythm of cortisol secretion, with low fasting morning plasma levels that increase after eating. On the other hand, most acromegalic patients with an unusual GH response to oral glucose suppression have GIPR-positive somatotropinomas, and a milder phenotype, and are more responsive to medical treatment. Neuroendocrine tumors are characterized by a strong GIPR expression that may correlate positively or inversely with the proliferative index MIB-1, and that seems an attractive target for developing novel radioligands. The main purpose of this review is to summarize the role of the GIP/GIPR axis in endocrine neoplasia, in the experimental and the clinical settings.
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Affiliation(s)
- Daniela Regazzo
- Department of Medicine Endocrinology Unit, Padova University Hospital, Padova, Italy
| | - Mattia Barbot
- Department of Medicine Endocrinology Unit, Padova University Hospital, Padova, Italy
| | - Carla Scaroni
- Department of Medicine Endocrinology Unit, Padova University Hospital, Padova, Italy
| | - Nora Albiger
- Endocrinology Service, ULSS 6 Euganea, Padova, Italy
| | - Gianluca Occhi
- Department of Biology, University of Padova, Padova, Italy.
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17
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Killion EA, Lu SC, Fort M, Yamada Y, Véniant MM, Lloyd DJ. Glucose-Dependent Insulinotropic Polypeptide Receptor Therapies for the Treatment of Obesity, Do Agonists = Antagonists? Endocr Rev 2020; 41:5568102. [PMID: 31511854 DOI: 10.1210/endrev/bnz002] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 09/03/2019] [Indexed: 12/19/2022]
Abstract
Glucose-dependent insulinotropic polypeptide receptor (GIPR) is associated with obesity in human genome-wide association studies. Similarly, mouse genetic studies indicate that loss of function alleles and glucose-dependent insulinotropic polypeptide overexpression both protect from high-fat diet-induced weight gain. Together, these data provide compelling evidence to develop therapies targeting GIPR for the treatment of obesity. Further, both antagonists and agonists alone prevent weight gain, but result in remarkable weight loss when codosed or molecularly combined with glucagon-like peptide-1 analogs preclinically. Here, we review the current literature on GIPR, including biology, human and mouse genetics, and pharmacology of both agonists and antagonists, discussing the similarities and differences between the 2 approaches. Despite opposite approaches being investigated preclinically and clinically, there may be viability of both agonists and antagonists for the treatment of obesity, and we expect this area to continue to evolve with new clinical data and molecular and pharmacological analyses of GIPR function.
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Affiliation(s)
- Elizabeth A Killion
- Department of Cardiometabolic Disorders, Amgen Research, Thousand Oaks, California
| | - Shu-Chen Lu
- Department of Cardiometabolic Disorders, Amgen Research, Thousand Oaks, California
| | - Madeline Fort
- Department of Comparative Biology and Safety Sciences, Amgen Research, Thousand Oaks, California
| | - Yuichiro Yamada
- Department of Endocrinology, Diabetes and Geriatric Medicine, Akita University Graduate School of Medicine, Akita, Japan
| | - Murielle M Véniant
- Department of Cardiometabolic Disorders, Amgen Research, Thousand Oaks, California
| | - David J Lloyd
- Department of Cardiometabolic Disorders, Amgen Research, Thousand Oaks, California
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18
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Beaudry JL, Kaur KD, Varin EM, Baggio LL, Cao X, Mulvihill EE, Bates HE, Campbell JE, Drucker DJ. Physiological roles of the GIP receptor in murine brown adipose tissue. Mol Metab 2019; 28:14-25. [PMID: 31451430 PMCID: PMC6822254 DOI: 10.1016/j.molmet.2019.08.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 07/27/2019] [Accepted: 08/06/2019] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVE Glucose-dependent insulinotropic polypeptide (GIP) is secreted from the gut in response to nutrient ingestion and promotes meal-dependent insulin secretion and lipid metabolism. Loss or attenuation of GIP receptor (GIPR) action leads to resistance to diet-induced obesity through incompletely understood mechanisms. The GIPR is expressed in white adipose tissue; however, its putative role in brown adipose tissue (BAT) has not been explored. METHODS We investigated the role of the GIPR in BAT cells in vitro and in BAT-specific (GiprBAT-/-) knockout mice with selective elimination of the Gipr within the Myf5+ expression domain. We analyzed body weight, adiposity, glucose homeostasis, insulin and lipid tolerance, energy expenditure, food intake, body temperature, and iBAT oxygen consumption ex vivo. High-fat diet (HFD)-fed GiprBAT-/- mice were studied at room temperature (21 °C), 4 °C, and 30 °C ambient temperatures. RESULTS The mouse Gipr gene is expressed in BAT, and GIP directly increased Il6 mRNA and IL-6 secretion in BAT cells. Additionally, levels of thermogenic, lipid and inflammation mRNA transcripts were altered in BAT cells transfected with Gipr siRNA. Body weight gain, energy expenditure, and glucose and insulin tolerance were normal in HFD-fed GiprBAT-/- mice housed at room temperature. However, GiprBAT-/- mice exhibited higher body temperatures during an acute cold challenge and a lower respiratory exchange ratio and impaired lipid tolerance at 21 °C. In contrast, body weight was lower and iBAT oxygen consumption was higher in HFD-fed mice housed at 4 °C but not at 30 °C. CONCLUSIONS The BAT GIPR is linked to the control of metabolic gene expression, fuel utilization, and oxygen consumption. However, the selective loss of the GIPR within BAT is insufficient to recapitulate the findings of decreased weight gain and resistance to obesity arising in experimental models with systemic disruption of GIP action.
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Affiliation(s)
- Jacqueline L Beaudry
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Kiran D Kaur
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Elodie M Varin
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Laurie L Baggio
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Xiemin Cao
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Erin E Mulvihill
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Holly E Bates
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Jonathan E Campbell
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Daniel J Drucker
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada; Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
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19
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Kaneko K, Fu Y, Lin HY, Cordonier EL, Mo Q, Gao Y, Yao T, Naylor J, Howard V, Saito K, Xu P, Chen SS, Chen MH, Xu Y, Williams KW, Ravn P, Fukuda M. Gut-derived GIP activates central Rap1 to impair neural leptin sensitivity during overnutrition. J Clin Invest 2019; 129:3786-3791. [PMID: 31403469 PMCID: PMC6715359 DOI: 10.1172/jci126107] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 06/11/2019] [Indexed: 01/16/2023] Open
Abstract
Nutrient excess, a major driver of obesity, diminishes hypothalamic responses to exogenously administered leptin, a critical hormone of energy balance. Here, we aimed to identify a physiological signal that arises from excess caloric intake and negatively controls hypothalamic leptin action. We found that deficiency of the gastric inhibitory polypeptide receptor (Gipr) for the gut-derived incretin hormone GIP protected against diet-induced neural leptin resistance. Furthermore, a centrally administered antibody that neutralizes GIPR had remarkable antiobesity effects in diet-induced obese mice, including reduced body weight and adiposity, and a decreased hypothalamic level of SOCS3, an inhibitor of leptin actions. In contrast, centrally administered GIP diminished hypothalamic sensitivity to leptin and increased hypothalamic levels of Socs3. Finally, we show that GIP increased the active form of the small GTPase Rap1 in the brain and that its activation was required for the central actions of GIP. Altogether, our results identify GIPR/Rap1 signaling in the brain as a molecular pathway linking overnutrition to the control of neural leptin actions.
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Affiliation(s)
- Kentaro Kaneko
- Children’s Nutrition Research Center, Department of Pediatrics and
| | - Yukiko Fu
- Children’s Nutrition Research Center, Department of Pediatrics and
| | - Hsiao-Yun Lin
- Children’s Nutrition Research Center, Department of Pediatrics and
| | | | - Qianxing Mo
- Dan L. Duncan Cancer Center and Center for Cell Gene and Therapy, Baylor College of Medicine, Houston, Texas, USA
| | - Yong Gao
- Division of Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
- National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Ting Yao
- Division of Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Medicine, Xi’an, Shaanxi, China
| | - Jacqueline Naylor
- AstraZeneca, R&D BioPharmaceuticals Unit, Cardiovascular, Renal and Metabolism, Cambridge, United Kingdom
| | - Victor Howard
- AstraZeneca, R&D BioPharmaceuticals Unit, Cardiovascular, Renal and Metabolism, Gaithersburg, Maryland, USA
| | - Kenji Saito
- Children’s Nutrition Research Center, Department of Pediatrics and
| | - Pingwen Xu
- Children’s Nutrition Research Center, Department of Pediatrics and
| | - Siyu S. Chen
- Children’s Nutrition Research Center, Department of Pediatrics and
| | - Miao-Hsueh Chen
- Children’s Nutrition Research Center, Department of Pediatrics and
| | - Yong Xu
- Children’s Nutrition Research Center, Department of Pediatrics and
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Kevin W. Williams
- Division of Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
| | - Peter Ravn
- AstraZeneca, R&D BioPharmaceuticals Unit, Department of Antibody Discovery and Protein Engineering, Cambridge, United Kingdom
| | - Makoto Fukuda
- Children’s Nutrition Research Center, Department of Pediatrics and
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20
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Hoizumi M, Sato T, Shimizu T, Kato S, Tsukiyama K, Narita T, Fujita H, Morii T, Sassa MH, Seino Y, Yamada Y. Inhibition of GIP signaling extends lifespan without caloric restriction. Biochem Biophys Res Commun 2019; 513:974-982. [PMID: 31003779 DOI: 10.1016/j.bbrc.2019.04.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 04/04/2019] [Indexed: 01/02/2023]
Abstract
AIMS/INTRODUCTION Caloric restriction (CR) promotes longevity and exerts anti-aging effects by increasing Sirtuin production and activation. Gastric inhibitory polypeptide (GIP), a gastrointestinal peptide hormone, exerts various effects on pancreatic β-cells and extra-pancreatic tissues. GIP promotes glucose-dependent augmentation of insulin secretion and uptake of nutrients into the adipose tissue. MATERIALS AND METHODS Gipr-/- and Gipr+/+ mice were used for lifespan analysis, behavior experiments and gene expression of adipose tissue and muscles. 3T3-L1 differentiated adipocytes were used for Sirt1 and Nampt expression followed by treatment with GIP and α-lipoic acid. RESULTS We observed that GIP receptor-knockout (Gipr-/-) mice fed normal diet showed an extended lifespan, increased exploratory and decreased anxiety-based behaviors, which are characteristic behavioral changes under CR. Moreover, Gipr-/- mice showed increased Sirt1 and Nampt expression in the adipose tissue. GIP suppressed α-lipoic acid-induced Sirt1 expression and activity in differentiated adipocytes. CONCLUSIONS Although maintenance of CR is difficult, food intake and muscle endurance of Gipr-/- mice were similar to those of wild-type mice. Inhibition of GIP signaling may be a novel strategy to extend the lifespan of diabetic patients.
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Affiliation(s)
- Manabu Hoizumi
- Department of Endocrinology, Diabetes and Geriatric Medicine, Akita University Graduate School of Medicine, Japan
| | - Takehiro Sato
- Department of Endocrinology, Diabetes and Geriatric Medicine, Akita University Graduate School of Medicine, Japan
| | - Tatsunori Shimizu
- Department of Endocrinology, Diabetes and Geriatric Medicine, Akita University Graduate School of Medicine, Japan
| | - Shunsuke Kato
- Department of Endocrinology, Diabetes and Geriatric Medicine, Akita University Graduate School of Medicine, Japan
| | - Katsushi Tsukiyama
- Department of Endocrinology, Diabetes and Geriatric Medicine, Akita University Graduate School of Medicine, Japan
| | - Takuma Narita
- Department of Endocrinology, Diabetes and Geriatric Medicine, Akita University Graduate School of Medicine, Japan
| | - Hiroki Fujita
- Department of Endocrinology, Diabetes and Geriatric Medicine, Akita University Graduate School of Medicine, Japan
| | - Tsukasa Morii
- Department of Endocrinology, Diabetes and Geriatric Medicine, Akita University Graduate School of Medicine, Japan
| | - Mariko Harada Sassa
- Institute for Advancement of Clinical and Translational Science, Kyoto University Hospital, Japan
| | - Yutaka Seino
- Kansai Electric Power Medical Research Institute, Osaka, Japan
| | - Yuichiro Yamada
- Department of Endocrinology, Diabetes and Geriatric Medicine, Akita University Graduate School of Medicine, Japan.
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21
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Tamamori-Adachi M, Koga A, Susa T, Fujii H, Tsuchiya M, Okinaga H, Hisaki H, Iizuka M, Kitajima S, Okazaki T. DNA damage response induced by Etoposide promotes steroidogenesis via GADD45A in cultured adrenal cells. Sci Rep 2018; 8:9636. [PMID: 29941883 PMCID: PMC6018231 DOI: 10.1038/s41598-018-27938-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 06/12/2018] [Indexed: 11/17/2022] Open
Abstract
Glucocorticoid production is regulated by adrenocorticotropic hormone (ACTH) via the cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathway in the adrenal cortex, but the changes in steroidogenesis associated with aging are unknown. In this study, we show that cell-autonomous steroidogenesis is induced by non-ACTH- mediated genotoxic stress in human adrenocortical H295R cells. Low-dose etoposide (EP) was used to induce DNA damage as a genotoxic stress, leading to cellular senescence. We found that steroidogenesis was promoted in cells stained with γH2AX, a marker of DNA damaged cells. Among stress-associated and p53-inducible genes, the expression of GADD45A and steroidogenesis-related genes was significantly upregulated. Immunofluorescence analysis revealed that GADD45A accumulated in the nuclei. Metabolite assay using cultured media showed that EP-treated cells were induced to produce and secrete considerable amounts of glucocorticoid. Knockdown of GADD45A using small interfering RNA markedly inhibited the EP-induced upregulation of steroidogenesis-related gene expression, and glucocorticoid production. A p38MAPK inhibitor, but not a PKA inhibitor, suppressed EP-stimulated steroidogenesis. These results suggest that DNA damage itself promotes steroidogenesis via one or more unprecedented non-ACTH-mediated pathway. Specifically, GADD45A plays a crucial role in the steroidogenic processes triggered by EP-stimulated genotoxic stress. Our study sheds new light on an alternate mechanism of steroidogenesis in the adrenal cortex.
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Affiliation(s)
- Mimi Tamamori-Adachi
- Department of Biochemistry, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan.
| | - Akane Koga
- Department of Biochemistry, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan.,Department of Practical Pharmacy, Faculty of Pharmaceutical Sciences, Teikyo University, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Takao Susa
- Department of Biochemistry, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Hiroko Fujii
- Department of Biochemistry, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan.,Department of General Medicine, National Defense Medical College, 3-2, Namiki, Tokorozawa City, Saitama, 359-8513, Japan
| | - Masao Tsuchiya
- Department of Practical Pharmacy, Faculty of Pharmaceutical Sciences, Teikyo University, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Hiroko Okinaga
- Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Harumi Hisaki
- Department of Biochemistry, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Masayoshi Iizuka
- Department of Biochemistry, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Shigetaka Kitajima
- Department of Biochemical Genetics, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8605, Japan
| | - Tomoki Okazaki
- Department of Biochemistry, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
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22
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Ussher JR, Campbell JE, Mulvihill EE, Baggio LL, Bates HE, McLean BA, Gopal K, Capozzi M, Yusta B, Cao X, Ali S, Kim M, Kabir MG, Seino Y, Suzuki J, Drucker DJ. Inactivation of the Glucose-Dependent Insulinotropic Polypeptide Receptor Improves Outcomes following Experimental Myocardial Infarction. Cell Metab 2018; 27:450-460.e6. [PMID: 29275960 DOI: 10.1016/j.cmet.2017.11.003] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 10/15/2017] [Accepted: 11/15/2017] [Indexed: 12/15/2022]
Abstract
Incretin hormones exert pleiotropic metabolic actions beyond the pancreas. Although the heart expresses both incretin receptors, the cardiac biology of GIP receptor (GIPR) action remains incompletely understood. Here we show that GIPR agonism did not impair the response to cardiac ischemia. In contrast, genetic elimination of the Gipr reduced myocardial infarction (MI)-induced ventricular injury and enhanced survival associated with reduced hormone sensitive lipase (HSL) phosphorylation; it also increased myocardial triacylglycerol (TAG) stores. Conversely, direct GIPR agonism in the isolated heart reduced myocardial TAG stores and increased fatty acid oxidation. The cardioprotective phenotype in Gipr-/- mice was partially reversed by pharmacological activation or genetic overexpression of HSL. Selective Gipr inactivation in cardiomyocytes phenocopied Gipr-/- mice, resulting in improved survival and reduced adverse remodeling following experimental MI. Hence, the cardiomyocyte GIPR regulates fatty acid metabolism and the adaptive response to ischemic cardiac injury. These findings have translational relevance for developing GIPR-based therapeutics.
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Affiliation(s)
- John R Ussher
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada; Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Jonathan E Campbell
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada; Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC 27701, USA
| | - Erin E Mulvihill
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Laurie L Baggio
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Holly E Bates
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Brent A McLean
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Keshav Gopal
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Megan Capozzi
- Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC 27701, USA
| | - Bernardo Yusta
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Xiemin Cao
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Safina Ali
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Minsuk Kim
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - M Golam Kabir
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Yutaka Seino
- Kansai Electric Power Hospital and Medical Research Institute, 2-1-7 Fukushima-ku, Osaka 553-0003, Japan
| | - Jinya Suzuki
- Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Daniel J Drucker
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada.
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Brandt SJ, Götz A, Tschöp MH, Müller TD. Gut hormone polyagonists for the treatment of type 2 diabetes. Peptides 2018; 100:190-201. [PMID: 29412819 PMCID: PMC5805859 DOI: 10.1016/j.peptides.2017.12.021] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 12/21/2017] [Accepted: 12/21/2017] [Indexed: 12/20/2022]
Abstract
Chemical derivatives of the gut-derived peptide hormone glucagon-like peptide 1 (GLP-1) are among the best-in-class pharmacotherapies to treat obesity and type 2 diabetes. However, GLP-1 analogs have modest weight lowering capacity, in the range of 5-10%, and the therapeutic window is hampered by dose-dependent side effects. Over the last few years, a new concept has emerged: combining the beneficial effects of several key metabolic hormones into a single molecular entity. Several unimolecular GLP-1-based polyagonists have shown superior metabolic action compared to GLP-1 monotherapies. In this review article, we highlight the history of polyagonists targeting the receptors for GLP-1, GIP and glucagon, and discuss recent progress in expanding of this concept to now allow targeted delivery of nuclear hormones via GLP-1 and other gut hormones, as a novel approach towards more personalized pharmacotherapies.
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Affiliation(s)
- Sara J Brandt
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Business Campus Garching, Parkring 13, 85748 Garching, Germany
| | - Anna Götz
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Business Campus Garching, Parkring 13, 85748 Garching, Germany; Department of Internal Medicine I, University Hospital RWTH Aachen, Aachen, Germany; Institute for Diabetes und Regeneration, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Business Campus Garching, Parkring 13, 85748, Garching, Germany
| | - Matthias H Tschöp
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Business Campus Garching, Parkring 13, 85748 Garching, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany; Division of Metabolic Diseases, Department of Medicine, Technische Universität München, Munich, Germany
| | - Timo D Müller
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Business Campus Garching, Parkring 13, 85748 Garching, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany.
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24
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Peverelli E, Catalano R, Giardino E, Treppiedi D, Morelli V, Ronchi CL, Vaczlavik A, Fusco N, Ferrero S, Bertherat J, Beuschlein F, Chiodini I, Arosio M, Spada A, Mantovani G. Cofilin is a cAMP effector in mediating actin cytoskeleton reorganization and steroidogenesis in mouse and human adrenocortical tumor cells. Cancer Lett 2017; 406:54-63. [PMID: 28826686 DOI: 10.1016/j.canlet.2017.07.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 07/20/2017] [Accepted: 07/27/2017] [Indexed: 11/17/2022]
Abstract
cAMP pathway plays a major role in the pathogenesis of cortisol-producing adrenocortical adenomas (CPA). cAMP-induced steroidogenesis is preceded by actin cytoskeleton reorganization, a process regulated by cofilin activity. In this study we investigated cofilin role in mediating cAMP effects on cell morphology and steroidogenesis in adrenocortical tumor cells. We demonstrated that forskolin induced cell rounding and strongly reduced phosphorylated (P)-cofilin/total cofilin ratio in Y1 (-52 ± 16%, p < 0.001) and human CPA cells (-53 ± 18%, p < 0.05). Cofilin silencing significantly reduced both forskolin-induced morphological changes and progesterone production (1.3-fold vs 1.8-fold in controls, p < 0.05), whereas transfection of wild-type or S3A (active), but not S3D (inactive) cofilin, potentiated forskolin effects on cell rounding and increased 3-fold progesterone synthesis with respect to control (p < 0.05). Furthermore, cofilin dephosphorylation by a ROCK inhibitor potentiated forskolin-induced cell rounding and steroidogenesis (2-fold increase vs forskolin alone). Finally, we found a reduced P-cofilin/total cofilin ratio and increased cofilin expression in CPA vs endocrine inactive adenomas by western blot and immunohistochemistry. Overall, these results identified cofilin as a mediator of cAMP effects on both morphological changes and steroidogenesis in mouse and human adrenocortical tumor cells.
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Affiliation(s)
- E Peverelli
- Endocrine Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy.
| | - R Catalano
- Endocrine Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - E Giardino
- Endocrine Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - D Treppiedi
- Endocrine Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - V Morelli
- Endocrine Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - C L Ronchi
- Department of Internal Medicine I, Division of Endocrinology and Diabetes, University Hospital, University of Wuerzburg, Wuerzburg, Germany
| | - A Vaczlavik
- Institut Cochin, Inserm U1016, CNRS UMR8104, Descartes University, Paris, France; Department of Endocrinology, Reference Center for Rare Adrenal Diseases, Hôpital Cochin, Paris, France
| | - N Fusco
- Division of Pathology, Fondazione IRCCS Ca' Granda-Ospedale Maggiore Policlinico, Milan, Italy; Department of Biomedical, Surgical and Dental Sciences, University of Milan Medical School, Milan, Italy
| | - S Ferrero
- Division of Pathology, Fondazione IRCCS Ca' Granda-Ospedale Maggiore Policlinico, Milan, Italy; Department of Biomedical, Surgical and Dental Sciences, University of Milan Medical School, Milan, Italy
| | - J Bertherat
- Institut Cochin, Inserm U1016, CNRS UMR8104, Descartes University, Paris, France; Department of Endocrinology, Reference Center for Rare Adrenal Diseases, Hôpital Cochin, Paris, France
| | - F Beuschlein
- Medizinische Klinik und Poliklinik IV, Endocrine Research Unit, Klinikum der Universität München, LMU, Munich, Germany
| | - I Chiodini
- Endocrine Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - M Arosio
- Endocrine Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - A Spada
- Endocrine Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - G Mantovani
- Endocrine Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
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25
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Blood pressure and glucose independent renoprotective effects of dipeptidyl peptidase-4 inhibition in a mouse model of type-2 diabetic nephropathy. J Hypertens 2016; 32:2211-23; discussion 2223. [PMID: 25215436 DOI: 10.1097/hjh.0000000000000328] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Despite the beneficial effects of type 4 dipeptidyl peptidase (DPP-4) inhibitors on glucose levels, its effects on diabetic nephropathy remain unclear. METHOD This study examined the long-term renoprotective effects of DPP-4 inhibitor linagliptin in db/db mice, a model of type 2 diabetes. Results were compared with the known beneficial effects of renin-angiotensin system blockade by enalapril. Ten-week-old male diabetic db/db mice were treated for 3 months with either vehicle (n = 10), 3 mg linagliptin/kg per day (n = 8), or 20 mg enalapril/kg per day (n = 10). Heterozygous db/m mice treated with vehicle served as healthy controls (n = 8). RESULTS Neither linagliptin nor enalapril had significant effects on the parameters of glucose metabolism or blood pressure in diabetic db/db mice. However, linagliptin treatment reduced albuminuria and attenuated kidney injury. In addition, expression of podocyte marker podocalyxin was normalized. We also analysed DPP-4 expression by immunofluorescence in human kidney biopsies and detected upregulation of DPP-4 in the glomeruli of patients with diabetic nephropathy, suggesting that our findings might be of relevance for human kidney disease as well. CONCLUSION Treatment with DPP-4 inhibitor linagliptin delays the progression of diabetic nephropathy damage in a glucose-independent and blood-pressure-independent manner. The observed effects may be because of the attenuation of podocyte injury and inhibition of myofibroblast transformation.
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26
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Hoekstra M, Van Eck M. HDL is redundant for adrenal steroidogenesis in LDLR knockout mice with a human-like lipoprotein profile. J Lipid Res 2016; 57:631-7. [PMID: 26891738 DOI: 10.1194/jlr.m066019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Indexed: 11/20/2022] Open
Abstract
The contribution of HDL to adrenal steroidogenesis appears to be different between mice and humans. In the current study, we tested the hypothesis that a difference in lipoprotein profile may be the underlying cause. Hereto, we determined the impact of HDL deficiency on the adrenal glucocorticoid output in genetically modified mice with a human-like lipoprotein profile. Genetic deletion of APOA1 in LDL receptor (LDLR) knockout mice was associated with HDL deficiency and a parallel increase in the level of cholesterol associated with nonHDL fractions. Despite a compensatory increase in the adrenal relative mRNA expression levels of the cholesterol synthesis gene, HMG-CoA reductase, adrenals from APOA1/LDLR double knockout mice were severely depleted of neutral lipids, as compared with those of control LDLR knockout mice. However, basal corticosterone levels and the adrenal glucocorticoid response to stress were not different between the two types of mice. In conclusion, we have shown that HDL is not critical for proper adrenal glucocorticoid function when mice are provided with a human-like lipoprotein profile. Our findings provide the first experimental evidence that APOB-containing lipoproteins may facilitate adrenal steroidogenesis, in an LDLR-independent manner, in vivo in mice.
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Affiliation(s)
- Menno Hoekstra
- Division of Biopharmaceutics, Cluster BioTherapeutics, Leiden Academic Centre for Drug Research, Gorlaeus Laboratories, 2333CC Leiden, The Netherlands
| | - Miranda Van Eck
- Division of Biopharmaceutics, Cluster BioTherapeutics, Leiden Academic Centre for Drug Research, Gorlaeus Laboratories, 2333CC Leiden, The Netherlands
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27
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Mieczkowska A, Mansur S, Bouvard B, Flatt PR, Thorens B, Irwin N, Chappard D, Mabilleau G. Double incretin receptor knock-out (DIRKO) mice present with alterations of trabecular and cortical micromorphology and bone strength. Osteoporos Int 2015; 26:209-18. [PMID: 25127672 DOI: 10.1007/s00198-014-2845-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 08/07/2014] [Indexed: 12/25/2022]
Abstract
UNLABELLED A role for gut hormone in bone physiology has been suspected. We evidenced alterations of microstructural morphology (trabecular and cortical) and bone strength (both at the whole-bone--and tissue-level) in double incretin receptor knock-out (DIRKO) mice as compared to wild-type littermates. These results support a role for gut hormones in bone physiology. INTRODUCTION The two incretins, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), have been shown to control bone remodeling and strength. However, lessons from single incretin receptor knock-out mice highlighted a compensatory mechanism induced by elevated sensitivity to the other gut hormone. As such, it is unclear whether the bone alterations observed in GIP or GLP-1 receptor deficient animals resulted from the lack of a functional gut hormone receptor, or by higher sensitivity for the other gut hormone. The aims of the present study were to investigate the bone microstructural morphology, as well as bone tissue properties, in double incretin receptor knock-out (DIRKO) mice. METHODS Twenty-six-week-old DIRKO mice were age- and sex-matched with wild-type (WT) littermates. Bone microstructural morphology was assessed at the femur by microCT and quantitative X-ray imaging, while tissue properties were investigated by quantitative backscattered electron imaging and Fourier-transformed infrared microscopy. Bone mechanical response was assessed at the whole-bone- and tissue-level by 3-point bending and nanoindentation, respectively. RESULTS As compared to WT animals, DIRKO mice presented significant augmentations in trabecular bone mass and trabecular number whereas bone outer diameter, cortical thickness, and cortical area were reduced. At the whole-bone-level, yield stress, ultimate stress, and post-yield work to fracture were significantly reduced in DIRKO animals. At the tissue-level, only collagen maturity was reduced by 9 % in DIRKO mice leading to reductions in maximum load, hardness, and dissipated energy. CONCLUSIONS This study demonstrated the critical role of gut hormones in controlling bone microstructural morphology and tissue properties.
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Affiliation(s)
- A Mieczkowska
- GEROM-LHEA UPRES EA 4658, Institut de Biologie en Santé, LUNAM Université, 4 rue larrey, 49933, Angers Cedex 09, France
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28
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Fujii H, Tamamori-Adachi M, Uchida K, Susa T, Nakakura T, Hagiwara H, Iizuka M, Okinaga H, Tanaka Y, Okazaki T. Marked cortisol production by intracrine ACTH in GIP-treated cultured adrenal cells in which the GIP receptor was exogenously introduced. PLoS One 2014; 9:e110543. [PMID: 25334044 PMCID: PMC4204891 DOI: 10.1371/journal.pone.0110543] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 09/16/2014] [Indexed: 12/21/2022] Open
Abstract
The ectopic expression of the glucose-dependent insulinotropic polypeptide receptor (GIPR) in the human adrenal gland causes significant hypercortisolemia after ingestion of each meal and leads to Cushing’s syndrome, implying that human GIPR activation is capable of robustly activating adrenal glucocorticoid secretion. In this study, we transiently transfected the human GIPR expression vector into cultured human adrenocortical carcinoma cells (H295R) and treated them with GIP to examine the direct link between GIPR activation and steroidogenesis. Using quantitative RT-PCR assay, we examined gene expression of steroidogenic related proteins, and carried out immunofluorescence analysis to prove that forced GIPR overexpression directly promotes production of steroidogenic enzymes CYP17A1 and CYP21A2 at the single cell level. Immunofluorescence showed that the transfection efficiency of the GIPR gene in H295R cells was approximately 5%, and GIP stimulation enhanced CYP21A2 and CYP17A1 expression in GIPR-introduced H295R cells (H295R-GIPR). Interestingly, these steroidogenic enzymes were also expressed in the GIPR (–) cells adjacent to the GIPR (+) cells. The mRNA levels of a cholesterol transport protein required for all steroidogenesis, StAR, and steroidogenic enzymes, HSD3β2, CYP11A1, CYP21A2, and CYP17A1 increased 1.2-2.1-fold in GIP-stimulated H295R-GIPR cells. These changes were reflected in the culture medium in which 1.5-fold increase in the cortisol concentration was confirmed. Furthermore, the levels of adenocorticotropic hormone (ACTH) receptor and ACTH precursor proopiomelanocortin (POMC) mRNA were upregulated 2- and 1.5-fold, respectively. Immunofluorescence showed that ACTH expression was detected in GIP-stimulated H295R-GIPR cells. An ACTH-receptor antagonist significantly inhibited steroidogenic gene expression and cortisol production. Immunostaining for both CYP17A1 and CYP21A2 was attenuated in cells treated with ACTH receptor antagonists as well as with POMC siRNA. These results demonstrated that GIPR activation promoted production and release of ACTH, and that steroidogenesis is activated by endogenously secreted ACTH following GIP administration, at least in part, in H295R cells.
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Affiliation(s)
- Hiroko Fujii
- Department of General Medicine, National Defense Medical College, Tokorozawa City, Saitama, Japan
- Department of Biochemistry, Teikyo University School of Medicine, Tokyo, Japan
| | - Mimi Tamamori-Adachi
- Department of Biochemistry, Teikyo University School of Medicine, Tokyo, Japan
- * E-mail: (MT-A); (TO)
| | - Kousuke Uchida
- Department of General Medicine, National Defense Medical College, Tokorozawa City, Saitama, Japan
- Department of Biochemistry, Teikyo University School of Medicine, Tokyo, Japan
| | - Takao Susa
- Department of Biochemistry, Teikyo University School of Medicine, Tokyo, Japan
| | - Takashi Nakakura
- Department of Anatomy, Teikyo University School of Medicine, Tokyo, Japan
| | - Haruo Hagiwara
- Department of Anatomy, Teikyo University School of Medicine, Tokyo, Japan
| | - Masayoshi Iizuka
- Department of Biochemistry, Teikyo University School of Medicine, Tokyo, Japan
| | - Hiroko Okinaga
- Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan
| | - Yuji Tanaka
- Department of General Medicine, National Defense Medical College, Tokorozawa City, Saitama, Japan
| | - Tomoki Okazaki
- Department of Biochemistry, Teikyo University School of Medicine, Tokyo, Japan
- * E-mail: (MT-A); (TO)
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29
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Varol C, Zvibel I, Spektor L, Mantelmacher FD, Vugman M, Thurm T, Khatib M, Elmaliah E, Halpern Z, Fishman S. Long-acting glucose-dependent insulinotropic polypeptide ameliorates obesity-induced adipose tissue inflammation. THE JOURNAL OF IMMUNOLOGY 2014; 193:4002-9. [PMID: 25217161 DOI: 10.4049/jimmunol.1401149] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Obesity induces low-grade chronic inflammation, manifested by proinflammatory polarization of adipose tissue innate and adaptive resident and recruited immune cells that contribute to insulin resistance (IR). The glucose-dependent insulinotropic polypeptide (GIP) is an incretin hormone that mediates postprandial insulin secretion and has anabolic effects on the adipose tissue. Importantly, recent evidence suggested that GIP is a potential suppressor of inflammation in several metabolic models. In this study, we aimed to investigate the immunoregulatory role of GIP in a murine model of diet-induced obesity (DIO) using the long-acting GIP analog [d-Ala(2)]GIP. Administration of [d-Ala(2)]GIP resulted in adipocytes of increased size, increased levels of adipose tissue lipid droplet proteins, indicating better lipid storage capacity, and reduced adipose tissue inflammation. Flow cytometry analysis revealed reduced numbers of inflammatory Ly6C(hi) monocytes and F4/80(hi)CD11c(+) macrophages, associated with IR. In addition, [d-Ala(2)]GIP reduced adipose tissue infiltration of IFN-γ-producing CD8(+) and CD4(+) T cells. Furthermore, [d-Ala(2)]GIP treatment induced a favorable adipose tissue adipokine profile, manifested by a prominent reduction in key inflammatory cytokines (TNF-α, IL-1β, IFN-γ) and chemokines (CCL2, CCL8, and CCL5) and an increase in adiponectin. Notably, [d-Ala(2)]GIP also reduced the numbers of circulating neutrophils and proinflammatory Ly6C(hi) monocytes in mice fed regular chow or a high-fat diet. Finally, the beneficial immune-associated effects were accompanied by amelioration of IR and improved insulin signaling in liver and adipose tissue. Collectively, our results describe key beneficial immunoregulatory properties for GIP in DIO and reveal that its augmentation ameliorates adipose tissue inflammation and improves IR.
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Affiliation(s)
- Chen Varol
- Research Center for Digestive Tract and Liver Diseases, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 64239, Israel; and
| | - Isabel Zvibel
- Research Center for Digestive Tract and Liver Diseases, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 64239, Israel; and
| | - Lior Spektor
- Research Center for Digestive Tract and Liver Diseases, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 64239, Israel; and
| | - Fernanda Dana Mantelmacher
- Research Center for Digestive Tract and Liver Diseases, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 64239, Israel; and
| | - Milena Vugman
- Research Center for Digestive Tract and Liver Diseases, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 64239, Israel; and
| | - Tamar Thurm
- Research Center for Digestive Tract and Liver Diseases, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 64239, Israel; and
| | - Marian Khatib
- Surgery Department, Tel-Aviv Sourasky Medical Center, Tel Aviv 64239, Israel
| | - Elinor Elmaliah
- Research Center for Digestive Tract and Liver Diseases, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 64239, Israel; and
| | - Zamir Halpern
- Research Center for Digestive Tract and Liver Diseases, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 64239, Israel; and
| | - Sigal Fishman
- Research Center for Digestive Tract and Liver Diseases, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 64239, Israel; and
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30
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Seino Y, Yabe D. Glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1: Incretin actions beyond the pancreas. J Diabetes Investig 2014; 4:108-30. [PMID: 24843641 PMCID: PMC4019264 DOI: 10.1111/jdi.12065] [Citation(s) in RCA: 183] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 01/24/2013] [Indexed: 12/14/2022] Open
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are the two primary incretin hormones secreted from the intestine on ingestion of various nutrients to stimulate insulin secretion from pancreatic β-cells glucose-dependently. GIP and GLP-1 undergo degradation by dipeptidyl peptidase-4 (DPP-4), and rapidly lose their biological activities. The actions of GIP and GLP-1 are mediated by their specific receptors, the GIP receptor (GIPR) and the GLP-1 receptor (GLP-1R), which are expressed in pancreatic β-cells, as well as in various tissues and organs. A series of investigations using mice lacking GIPR and/or GLP-1R, as well as mice lacking DPP-4, showed involvement of GIP and GLP-1 in divergent biological activities, some of which could have implications for preventing diabetes-related microvascular complications (e.g., retinopathy, nephropathy and neuropathy) and macrovascular complications (e.g., coronary artery disease, peripheral artery disease and cerebrovascular disease), as well as diabetes-related comorbidity (e.g., obesity, non-alcoholic fatty liver disease, bone fracture and cognitive dysfunction). Furthermore, recent studies using incretin-based drugs, such as GLP-1 receptor agonists, which stably activate GLP-1R signaling, and DPP-4 inhibitors, which enhance both GLP-1R and GIPR signaling, showed that GLP-1 and GIP exert effects possibly linked to prevention or treatment of diabetes-related complications and comorbidities independently of hyperglycemia. We review recent findings on the extrapancreatic effects of GIP and GLP-1 on the heart, brain, kidney, eye and nerves, as well as in the liver, fat and several organs from the perspective of diabetes-related complications and comorbidities.
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Affiliation(s)
| | - Daisuke Yabe
- Division of Diabetes Clinical Nutrition and Endocrinology Kansai Electric Power Hospital Osaka Japan
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31
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Ussher JR, Keung W, Fillmore N, Koves TR, Mori J, Zhang L, Lopaschuk DG, Ilkayeva OR, Wagg CS, Jaswal JS, Muoio DM, Lopaschuk GD. Treatment with the 3-ketoacyl-CoA thiolase inhibitor trimetazidine does not exacerbate whole-body insulin resistance in obese mice. J Pharmacol Exp Ther 2014; 349:487-96. [PMID: 24700885 DOI: 10.1124/jpet.114.214197] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
There is a growing need to understand the underlying mechanisms involved in the progression of cardiovascular disease during obesity and diabetes. Although inhibition of fatty acid oxidation has been proposed as a novel approach to treat ischemic heart disease and heart failure, reduced muscle fatty acid oxidation rates may contribute to the development of obesity-associated insulin resistance. Our aim was to determine whether treatment with the antianginal agent trimetazidine, which inhibits fatty acid oxidation in the heart secondary to inhibition of 3-ketoacyl-CoA thiolase (3-KAT), may have off-target effects on glycemic control in obesity. We fed C57BL/6NCrl mice a high-fat diet (HFD) for 10 weeks before a 22-day treatment with the 3-KAT inhibitor trimetazidine (15 mg/kg per day). Insulin resistance was assessed via glucose/insulin tolerance testing, and lipid metabolite content was assessed in gastrocnemius muscle. Trimetazidine-treatment led to a mild shift in substrate preference toward carbohydrates as an oxidative fuel source in obese mice, evidenced by an increase in the respiratory exchange ratio. This shift in metabolism was accompanied by an accumulation of long-chain acyl-CoA and a trend to an increase in triacylglycerol content in gastrocnemius muscle, but did not exacerbate HFD-induced insulin resistance compared with control-treated mice. It is noteworthy that trimetazidine treatment reduced palmitate oxidation rates in the isolated working mouse heart and neonatal cardiomyocytes but not C2C12 skeletal myotubes. Our findings demonstrate that trimetazidine therapy does not adversely affect HFD-induced insulin resistance, suggesting that treatment with trimetazidine would not worsen glycemic control in obese patients with angina.
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Affiliation(s)
- John R Ussher
- Cardiovascular Research Centre, Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada (J.R.U., W.K., N.F., J.M., L.Z., D.G.L., C.S.W., J.S.J., G.D.L.); and Sarah W. Stedman Nutrition and Metabolism Center (T.R.K., O.R.I., D.M.M.), Department of Medicine (T.R.K., O.R.I., D.M.M.), Department of Pharmacology and Cancer Biology (D.M.M.), Duke University, Durham, North Carolina
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Yabe D, Seino Y. Incretin actions beyond the pancreas: lessons from knockout mice. Curr Opin Pharmacol 2013; 13:946-53. [DOI: 10.1016/j.coph.2013.09.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 09/13/2013] [Accepted: 09/13/2013] [Indexed: 02/06/2023]
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Abstract
Incretin peptides, principally GLP-1 and GIP, regulate islet hormone secretion, glucose concentrations, lipid metabolism, gut motility, appetite and body weight, and immune function, providing a scientific basis for utilizing incretin-based therapies in the treatment of type 2 diabetes. Activation of GLP-1 and GIP receptors also leads to nonglycemic effects in multiple tissues, through direct actions on tissues expressing incretin receptors and indirect mechanisms mediated through neuronal and endocrine pathways. Here we contrast the pharmacology and physiology of incretin hormones and review recent advances in mechanisms coupling incretin receptor signaling to pleiotropic metabolic actions in preclinical studies. We discuss whether mechanisms identified in preclinical studies have potential translational relevance for the treatment of human disease and highlight controversies and uncertainties in incretin biology that require resolution in future studies.
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Affiliation(s)
- Jonathan E Campbell
- Department of Medicine, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Daniel J Drucker
- Department of Medicine, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada.
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