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McGavigan AK, O'Hara HC, Amin A, Kinsey-Jones J, Spreckley E, Alamshah A, Agahi A, Banks K, France R, Hyberg G, Wong C, Bewick GA, Gardiner JV, Lehmann A, Martin NM, Ghatei MA, Bloom SR, Murphy KG. L-cysteine suppresses ghrelin and reduces appetite in rodents and humans. Int J Obes (Lond) 2014; 39:447-55. [PMID: 25219528 PMCID: PMC4276721 DOI: 10.1038/ijo.2014.172] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 08/28/2014] [Accepted: 09/08/2014] [Indexed: 12/13/2022]
Abstract
BACKGROUND High-protein diets promote weight loss and subsequent weight maintenance, but are difficult to adhere to. The mechanisms by which protein exerts these effects remain unclear. However, the amino acids produced by protein digestion may have a role in driving protein-induced satiety. METHODS We tested the effects of a range of amino acids on food intake in rodents and identified l-cysteine as the most anorexigenic. Using rodents we further studied the effect of l-cysteine on food intake, behaviour and energy expenditure. We proceeded to investigate its effect on neuronal activation in the hypothalamus and brainstem before investigating its effect on gastric emptying and gut hormone release. The effect of l-cysteine on appetite scores and gut hormone release was then investigated in humans. RESULTS l-Cysteine dose-dependently decreased food intake in both rats and mice following oral gavage and intraperitoneal administration. This effect did not appear to be secondary to behavioural or aversive side effects. l-Cysteine increased neuronal activation in the area postrema and delayed gastric emptying. It suppressed plasma acyl ghrelin levels and did not reduce food intake in transgenic ghrelin-overexpressing mice. Repeated l-cysteine administration decreased food intake in rats and obese mice. l-Cysteine reduced hunger and plasma acyl ghrelin levels in humans. CONCLUSIONS Further work is required to determine the chronic effect of l-cysteine in rodents and humans on appetite and body weight, and whether l-cysteine contributes towards protein-induced satiety.
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Affiliation(s)
- A K McGavigan
- Department of Investigative Medicine, Imperial College London, London, UK
| | - H C O'Hara
- Department of Investigative Medicine, Imperial College London, London, UK
| | - A Amin
- Department of Investigative Medicine, Imperial College London, London, UK
| | - J Kinsey-Jones
- Department of Investigative Medicine, Imperial College London, London, UK
| | - E Spreckley
- Department of Investigative Medicine, Imperial College London, London, UK
| | - A Alamshah
- Department of Investigative Medicine, Imperial College London, London, UK
| | - A Agahi
- Department of Investigative Medicine, Imperial College London, London, UK
| | - K Banks
- Department of Investigative Medicine, Imperial College London, London, UK
| | - R France
- Department of Investigative Medicine, Imperial College London, London, UK
| | - G Hyberg
- AstraZeneca R&D, Mölndal, Sweden
| | - C Wong
- Department of Investigative Medicine, Imperial College London, London, UK
| | - G A Bewick
- 1] Department of Investigative Medicine, Imperial College London, London, UK [2] Division of Diabetes & Nutritional Sciences, King's College London, London, UK
| | - J V Gardiner
- Department of Investigative Medicine, Imperial College London, London, UK
| | - A Lehmann
- 1] AstraZeneca R&D, Mölndal, Sweden [2] NextRx, Gothenburg, Sweden
| | - N M Martin
- Department of Investigative Medicine, Imperial College London, London, UK
| | - M A Ghatei
- Department of Investigative Medicine, Imperial College London, London, UK
| | - S R Bloom
- Department of Investigative Medicine, Imperial College London, London, UK
| | - K G Murphy
- Department of Investigative Medicine, Imperial College London, London, UK
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2
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Psichas A, Sleeth ML, Murphy KG, Brooks L, Bewick GA, Hanyaloglu AC, Ghatei MA, Bloom SR, Frost G. The short chain fatty acid propionate stimulates GLP-1 and PYY secretion via free fatty acid receptor 2 in rodents. Int J Obes (Lond) 2014; 39:424-9. [PMID: 25109781 PMCID: PMC4356745 DOI: 10.1038/ijo.2014.153] [Citation(s) in RCA: 467] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 06/03/2014] [Accepted: 06/25/2014] [Indexed: 12/24/2022]
Abstract
Background and Objectives: The gut hormones peptide YY (PYY) and glucagon-like peptide 1 (GLP-1) acutely suppress appetite. The short chain fatty acid (SCFA) receptor, free fatty acid receptor 2 (FFA2) is present on colonic enteroendocrine L cells, and a role has been suggested for SCFAs in appetite regulation. Here, we characterise the in vitro and in vivo effects of colonic propionate on PYY and GLP-1 release in rodents, and investigate the role of FFA2 in mediating these effects using FFA2 knockout mice. Methods: We used Wistar rats, C57BL6 mice and free fatty acid receptor 2 knockout (FFA−/−) mice on a C57BL6 background to explore the impact of the SCFA propionate on PYY and GLP-1 release. Isolated colonic crypt cultures were used to assess the effects of propionate on gut hormone release in vitro. We subsequently developed an in vivo technique to assess gut hormone release into the portal vein following colonic infusion of propionate. Results: Propionate stimulated the secretion of both PYY and GLP-1 from wild-type primary murine colonic crypt cultures. This effect was significantly attenuated in cultures from FFA2−/− mice. Intra-colonic infusion of propionate elevated PYY and GLP-1 levels in jugular vein plasma in rats and in portal vein plasma in both rats and mice. However, propionate did not significantly stimulate gut hormone release in FFA2−/− mice. Conclusions: Intra-colonic administration of propionate stimulates the concurrent release of both GLP-1 and PYY in rats and mice. These data demonstrate that FFA2 deficiency impairs SCFA-induced gut hormone secretion both in vitro and in vivo.
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Affiliation(s)
- A Psichas
- Nutrition and Dietetic Research Group, Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - M L Sleeth
- Nutrition and Dietetic Research Group, Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - K G Murphy
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - L Brooks
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - G A Bewick
- 1] Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK [2] Division of Diabetes & Nutritional Sciences, Kings College London, Yeovil, UK
| | - A C Hanyaloglu
- Department of Surgery and Cancer, Institute of Reproductive and Developmental Biology, Imperial College, London, UK
| | - M A Ghatei
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - S R Bloom
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - G Frost
- Nutrition and Dietetic Research Group, Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
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Beale K, Gardiner JV, Bewick GA, Hostomska K, Patel NA, Hussain SS, Jayasena CN, Ebling FJP, Jethwa PH, Prosser HM, Lattanzi R, Negri L, Ghatei MA, Bloom SR, Dhillo WS. Peripheral administration of prokineticin 2 potently reduces food intake and body weight in mice via the brainstem. Br J Pharmacol 2013; 168:403-10. [PMID: 22935107 DOI: 10.1111/j.1476-5381.2012.02191.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Revised: 08/02/2012] [Accepted: 08/06/2012] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND AND PURPOSE Prokineticin 2 (PK2) has recently been shown to acutely reduce food intake in rodents. We aimed to determine the CNS sites and receptors that mediate the anorectic effects of peripherally administered PK2 and its chronic effects on glucose and energy homeostasis. EXPERIMENTAL APPROACH We investigated neuronal activation following i.p. administration of PK2 using c-Fos-like immunoreactivity (CFL-IR). The anorectic effect of PK2 was examined in mice with targeted deletion of either prokineticin receptor 1 (PKR1) or prokineticin receptor 2 (PKR2), and in wild-type mice following administration of the PKR1 antagonist, PC1. The effect of IP PK2 administration on glucose homeostasis was investigated. Finally, the effect of long-term administration of PK2 on glucose and energy homeostasis in diet-induced obese (DIO) mice was determined. KEY RESULTS I.p. PK2 administration significantly increased CFL-IR in the dorsal motor vagal nucleus of the brainstem. The anorectic effect of PK2 was maintained in mice lacking the PKR2 but abolished in mice lacking PKR1 and in wild-type mice pre-treated with PC1. DIO mice treated chronically with PK2 had no changes in glucose levels but significantly reduced food intake and body weight compared to controls. CONCLUSIONS AND IMPLICATIONS Together, our data suggest that the anorectic effects of peripherally administered PK2 are mediated via the brainstem and this effect requires PKR1 but not PKR2 signalling. Chronic administration of PK2 reduces food intake and body weight in a mouse model of human obesity, suggesting that PKR1-selective agonists have potential to be novel therapeutics for the treatment of obesity.
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Affiliation(s)
- Kel Beale
- Section of Investigative Medicine, Imperial College London, London, UK
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Boughton CK, Patterson M, Bewick GA, Tadross JA, Gardiner JV, Beale KEL, Chaudery F, Hunter G, Busbridge M, Leavy EM, Ghatei MA, Bloom SR, Murphy KG. Alarin stimulates food intake and gonadotrophin release in male rats. Br J Pharmacol 2011; 161:601-13. [PMID: 20880399 DOI: 10.1111/j.1476-5381.2010.00893.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE Alarin is a recently discovered member of the galanin peptide family encoded by a splice variant of galanin-like peptide (GALP) mRNA. Galanin and GALP regulate energy homeostasis and reproduction. We therefore investigated the effects of alarin on food intake and gonadotrophin release. EXPERIMENTAL APPROACH Alarin was administered into the third cerebral ventricle (i.c.v.) of rats, and food intake or circulating hormone levels were measured. The effect of alarin on the hypothalamo-pituitary-gonadal axis was investigated in vitro using hypothalamic and anterior pituitary explants, and immortalized cell lines. Receptor binding assays were used to determine whether alarin binds to galanin receptors. KEY RESULTS The i.c.v. administration of alarin (30 nmol) to ad libitum fed male rats significantly increased acute food intake to 500%, and plasma luteinizing hormone (LH) levels to 170% of responses to saline. In vitro, 100 nM alarin stimulated neuropeptide Y (NPY) and gonadotrophin-releasing hormone (GnRH) release from hypothalamic explants from male rats, and 1000 nM alarin increased GnRH release from GT1-7 cells. In vivo, pretreatment with the GnRH receptor antagonist cetrorelix prevented the increase in plasma LH levels observed following i.c.v. alarin administration. Receptor binding studies confirmed alarin did not bind to any known galanin receptor, or compete with radiolabelled galanin for hypothalamic binding sites. CONCLUSIONS AND IMPLICATIONS These results suggest alarin is a novel orexigenic peptide, and that it increases circulating LH levels via hypothalamic GnRH. Further work is required to identify the receptor(s) mediating the biological effects of alarin.
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Affiliation(s)
- C K Boughton
- Department of Investigative Medicine, Imperial College London, Commonwealth Building, Du Cane Road, London, UK
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5
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Gardiner JV, Beale KE, Roy D, Boughton CK, Bataveljic A, Campbell DC, Bewick GA, Patel NA, Patterson M, Leavy EM, Ghatei MA, Bloom SR, Dhillo WS. Cerebellin1 is a novel orexigenic peptide. Diabetes Obes Metab 2010; 12:883-90. [PMID: 20920041 DOI: 10.1111/j.1463-1326.2010.01247.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIM Cerebellin1 (Cbln1) is highly expressed in the hypothalamus, a region of the brain involved in appetite regulation. However, the effects of Cbn1 on food intake are not known. The present study aimed to investigate the effect of Cbln1 on appetite regulation in rats. METHODS We determined the effect of (i) intracerebroventricular (ICV) injection of Cbln1 on food intake, behaviour and plasma pituitary hormone levels in male Wistar rats; (ii) Cbln1 on the release of hypothalamic neuropeptides known to modulate food intake from hypothalamic explants and (iii) fasting on hypothalamic Cbln1 mRNA expression. RESULTS (i) ICV administration of Cbln1 significantly increased food intake in rats and caused no adverse behaviours. ICV administration of Cbln1 significantly reduced plasma thyroid stimulating hormone (TSH) levels 10 min postinjection in rats. (ii) Cbln1 significantly increased the release of neuropeptide Y (NPY) from hypothalamic explants. (iii) Cbln1 mRNA expression levels were increased in the ventromedial nucleus of the hypothalamus in fasted rats. CONCLUSIONS These data suggest that Cbln1 is a novel orexigenic peptide, which may mediate its effects via hypothalamic NPY.
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Affiliation(s)
- J V Gardiner
- Department of Investigative Medicine, Hammersmith Hospital, Imperial College London, London, UK
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Dhillo WS, Bewick GA, White NE, Gardiner JV, Thompson EL, Bataveljic A, Murphy KG, Roy D, Patel NA, Scutt JN, Armstrong A, Ghatei MA, Bloom SR. The thyroid hormone derivative 3-iodothyronamine increases food intake in rodents. Diabetes Obes Metab 2009; 11:251-60. [PMID: 18671794 DOI: 10.1111/j.1463-1326.2008.00935.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The thyroid hormone derivative 3-iodothyronamine (T(1)AM), an endogenous biogenic amine, is a potent agonist of the G protein-coupled trace amine-associated receptor 1 (TAAR1). T(1)AM is present in rat brain, and TAAR1 is expressed in hypothalamic nuclei associated with the regulation of energy homeostasis. AIM The aim of this study was to determine the effects of T(1)AM on food intake in rodents. METHODS We determined the effect of (i) intraperitoneal (i.p.) administration of T(1)AM on food intake, oxygen consumption (VO(2)) and locomotor activity in mice; (ii) intracerebroventricular (ICV) injection of T(1)AM on food intake in male rats; (iii) c-fos expression following ventricular administration of T(1)AM in male rats; and (iv) direct injection of T(1)AM into the arcuate nucleus (ARC) of male rats on food intake. RESULTS (i) T(1)AM (4 nmol/kg) significantly increased food intake following i.p. injection in mice but had no effect on VO(2) or locomotor activity. (ii) ICV administration of T(1)AM (1.2 nmol/kg) significantly increased food intake in male rats. (iii) Intraventricular administration of T(1)AM significantly increased c-fos expression in the ARC of male rats. (iv) Direct administration of T(1)AM (0.12, 0.4 and 1.2 nmol/kg) into the ARC of male rats significantly increased food intake. CONCLUSION These data suggest that T(1)AM is an orexigenic factor that may act through the ARC to increase food intake in rodents.
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Affiliation(s)
- W S Dhillo
- Department of Investigative Medicine, Faculty of Medicine, Imperial College London, Hammersmith Hospital, London, UK
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Dhillo WS, Gardiner JV, Castle L, Bewick GA, Smith KL, Meeran K, Todd JF, Ghatei MA, Bloom SR. Agouti Related Protein (AgRP) is Upregulated in Cushing's Syndrome. Exp Clin Endocrinol Diabetes 2005; 113:602-6. [PMID: 16320160 DOI: 10.1055/s-2005-872895] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Alpha melanocyte-stimulating hormone (alpha-MSH) is an agonist at the melanocortin 3 (MC3-R) and melanocortin 4 (MC4-R) receptors. Alpha-MSH stimulates corticosterone release from rat and human adrenal cells. Patients with Cushing's syndrome have elevated levels of serum alpha-MSH. Agouti related protein (AgRP) is an endogenous antagonist at the MC3-R and MC4-R and is expressed in the rat adrenal cortex. AgRP antagonises alpha-MSH-induced corticosterone release from rat and bovine adrenal cells. This suggests that AgRP may have an inhibitory paracrine role in the adrenal gland. We measured adrenal AgRP mRNA expression and circulating AgRP in 2 patients with Cushing's syndrome and controls. Adrenal AgRP mRNA expression and plasma AgRP were higher in the patients with Cushing's syndrome compared to controls. Plasma AgRP in the patients with Cushing's syndrome following bilateral adrenalectomy and hydrocortisone replacement were similar to the levels seen in controls. Our results suggest that AgRP may have a novel inhibitory paracrine role in the human adrenal gland.
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Affiliation(s)
- W S Dhillo
- Department of Metabolic Medicine, Faculty of Medicine, Imperial College, 6th Floor Commonwealth Building, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
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Stanley SA, Murphy KG, Bewick GA, Kong WM, Opacka-Juffry J, Gardiner JV, Ghatei M, Small CJ, Bloom SR. Regulation of rat pituitary cocaine- and amphetamine-regulated transcript (CART) by CRH and glucocorticoids. Am J Physiol Endocrinol Metab 2004; 287:E583-90. [PMID: 15138156 DOI: 10.1152/ajpendo.00576.2003] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cocaine- and amphetamine-regulated transcript (CART) was originally isolated from rat brain, but CART is also synthesized and stored in the anterior pituitary. The localization of pituitary CART and factors regulating its synthesis are largely unknown. The regulation of pituitary CART synthesis and release in response to CRH and glucocorticoids was examined in vitro and in vivo. CART immunoreactivity (CART-IR) was released from anterior pituitary segments. This release was increased 15-fold in response to corticotropin-releasing hormone (CRH). Intraperitoneal administration of CRH to rats significantly increased plasma CART-IR. Furthermore, CART-IR content and plasma CART-IR were significantly increased in adrenalectomized rats, and anterior pituitary CART mRNA expression, CART-IR content, and plasma CART-IR were significantly decreased in corticosterone-treated rats. Plasma CART-IR showed a pattern of diurnal variation similar to that of ACTH and corticosterone, and plasma CART-IR was positively correlated with corticosterone. CART-IR was detectable in the medium of the corticotroph cell line AtT-20. Dual in situ hybridization for prepro-CART (ppCART) mRNA expression and immunocytochemistry for ACTH showed localization of ppCART mRNA to a subpopulation of ACTH-immunoreactive cells. These findings demonstrate that pituitary CART expression and release are regulated by CRH and the glucocorticoid environment and that pituitary CART is partly localized to corticotrophs.
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Affiliation(s)
- S A Stanley
- Endocrine Unit, Faculty of Medicine, ICSTM, Hammersmith Hospital, London W12 0NN, United Kingdom
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Dhillo WS, Small CJ, Gardiner JV, Bewick GA, Whitworth EJ, Jethwa PH, Seal LJ, Ghatei MA, Hinson JP, Bloom SR. Agouti-related protein has an inhibitory paracrine role in the rat adrenal gland. Biochem Biophys Res Commun 2003; 301:102-7. [PMID: 12535647 DOI: 10.1016/s0006-291x(02)02991-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
alpha-Melanocyte-stimulating-hormone (alpha-MSH) is an agonist at the melanocortin 3 receptor (MC3-R) and melanocortin 4 receptor (MC4-R). alpha-MSH stimulates corticosterone release from rat adrenal glomerulosa cells in vitro. Agouti-related protein (AgRP) an endogenous antagonist at the MC3-R and MC4-R, is expressed in the adrenal gland. We investigated the expression of the MC3-R and MC4-R and the role of AgRP in the adrenal gland. MC3-R and MC4-R expression was detected in rat adrenal gland using RT-PCR. The effect of AgRP on alpha-MSH-induced corticosterone release was investigated using dispersed rat adrenal glomerulosa cells. AgRP administered alone did not affect corticosterone release, but co-administration of AgRP and alpha-MSH attenuated alpha-MSH-induced corticosterone release. To investigate glucocorticoid feedback, adrenal AgRP expression was compared in rats treated with dexamethasone to controls. AgRP mRNA was increased in rats treated with dexamethasone treatment compared to controls. Our findings demonstrate that adrenal AgRP mRNA is regulated by glucocorticoids. AgRP acting via the MC3-R or MC4-R may have an inhibitory paracrine role, blocking alpha-MSH-induced corticosterone secretion.
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Affiliation(s)
- W S Dhillo
- Endocrine Unit, Faculty of Medicine, Imperial College, 6th Floor Commonwealth Building, Hammersmith Hospital, Du Cane Road, London W12 ONN, UK
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