Influence of dexamethasone and weight loss on the regulation of serum leptin levels in obese individuals

The adipocyte hormone leptin is thought to serve as a signal to the central nervous system reflecting the status of fat stores. Serum leptin levels and adipocyte leptin messenger RNA levels are clearly increased in obesity. Nevertheless, the factors regulating leptin production are not fully underst...

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Main Authors: D.D.G. Lerario, S.R.G. Ferreira, W.L. Miranda, A.R. Chacra
Format: Article
Language:English
Published: Associação Brasileira de Divulgação Científica 2001-04-01
Series:Brazilian Journal of Medical and Biological Research
Subjects:
Online Access:http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000400007
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author D.D.G. Lerario
S.R.G. Ferreira
W.L. Miranda
A.R. Chacra
author_facet D.D.G. Lerario
S.R.G. Ferreira
W.L. Miranda
A.R. Chacra
author_sort D.D.G. Lerario
collection DOAJ
description The adipocyte hormone leptin is thought to serve as a signal to the central nervous system reflecting the status of fat stores. Serum leptin levels and adipocyte leptin messenger RNA levels are clearly increased in obesity. Nevertheless, the factors regulating leptin production are not fully understood. The aim of this study was to determine the effects of in vivo administration of the synthetic glucocorticoid dexamethasone and weight loss on serum leptin levels in two independent protocols. Twenty-five obese subjects were studied (18 women and 7 men, mean age 26.6 ± 6 years, BMI 31.1 ± 2.5 kg/m², %fat 40.3 ± 8.3) and compared at baseline to 22 healthy individuals. Serum levels of leptin, insulin, proinsulin and glucose were assessed at baseline and after ingestion of dexamethasone, 4 mg per day (2 mg, twice daily) for two consecutive days. To study the effects of weight loss on serum leptin, 17 of the obese subjects were submitted to a low-calorie dietary intervention trial for 8 weeks and again blood samples were collected. Serum leptin levels were significantly higher in the obese group compared to the control group and a high positive correlation between leptinemia and the magnitude of fat mass was found (r = 0.88, P<0.0001). After dexamethasone, there was a significant increase in serum leptin levels (22.9 ± 12.3 vs 51.4 ± 23.3 ng/ml, P<0.05). Weight loss (86.1 ± 15.1 vs 80.6 ± 14.2 kg, P<0.05) led to a reduction in leptin levels (25.13 ± 12.8 vs 15.9 ± 9.1 ng/ml, P<0.05). We conclude that serum leptin levels are primordially dependent on fat mass magnitude. Glucocorticoids at supraphysiologic levels are potent secretagogues of leptin in obese subjects and a mild fat mass reduction leads to a disproportionate decrease in serum leptin levels. This suggests that, in addition to the changes in fat mass, complex nutritional and hormonal interactions may also play an important role in the regulation of leptin levels.
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spelling doaj.art-4ba3e707107c4b328ca1fd9b58f792fc2022-12-21T23:52:50ZengAssociação Brasileira de Divulgação CientíficaBrazilian Journal of Medical and Biological Research0100-879X1414-431X2001-04-0134447948710.1590/S0100-879X2001000400007Influence of dexamethasone and weight loss on the regulation of serum leptin levels in obese individualsD.D.G. LerarioS.R.G. FerreiraW.L. MirandaA.R. ChacraThe adipocyte hormone leptin is thought to serve as a signal to the central nervous system reflecting the status of fat stores. Serum leptin levels and adipocyte leptin messenger RNA levels are clearly increased in obesity. Nevertheless, the factors regulating leptin production are not fully understood. The aim of this study was to determine the effects of in vivo administration of the synthetic glucocorticoid dexamethasone and weight loss on serum leptin levels in two independent protocols. Twenty-five obese subjects were studied (18 women and 7 men, mean age 26.6 ± 6 years, BMI 31.1 ± 2.5 kg/m², %fat 40.3 ± 8.3) and compared at baseline to 22 healthy individuals. Serum levels of leptin, insulin, proinsulin and glucose were assessed at baseline and after ingestion of dexamethasone, 4 mg per day (2 mg, twice daily) for two consecutive days. To study the effects of weight loss on serum leptin, 17 of the obese subjects were submitted to a low-calorie dietary intervention trial for 8 weeks and again blood samples were collected. Serum leptin levels were significantly higher in the obese group compared to the control group and a high positive correlation between leptinemia and the magnitude of fat mass was found (r = 0.88, P<0.0001). After dexamethasone, there was a significant increase in serum leptin levels (22.9 ± 12.3 vs 51.4 ± 23.3 ng/ml, P<0.05). Weight loss (86.1 ± 15.1 vs 80.6 ± 14.2 kg, P<0.05) led to a reduction in leptin levels (25.13 ± 12.8 vs 15.9 ± 9.1 ng/ml, P<0.05). We conclude that serum leptin levels are primordially dependent on fat mass magnitude. Glucocorticoids at supraphysiologic levels are potent secretagogues of leptin in obese subjects and a mild fat mass reduction leads to a disproportionate decrease in serum leptin levels. This suggests that, in addition to the changes in fat mass, complex nutritional and hormonal interactions may also play an important role in the regulation of leptin levels.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000400007obesityleptinweight reductiondexamethasone
spellingShingle D.D.G. Lerario
S.R.G. Ferreira
W.L. Miranda
A.R. Chacra
Influence of dexamethasone and weight loss on the regulation of serum leptin levels in obese individuals
Brazilian Journal of Medical and Biological Research
obesity
leptin
weight reduction
dexamethasone
title Influence of dexamethasone and weight loss on the regulation of serum leptin levels in obese individuals
title_full Influence of dexamethasone and weight loss on the regulation of serum leptin levels in obese individuals
title_fullStr Influence of dexamethasone and weight loss on the regulation of serum leptin levels in obese individuals
title_full_unstemmed Influence of dexamethasone and weight loss on the regulation of serum leptin levels in obese individuals
title_short Influence of dexamethasone and weight loss on the regulation of serum leptin levels in obese individuals
title_sort influence of dexamethasone and weight loss on the regulation of serum leptin levels in obese individuals
topic obesity
leptin
weight reduction
dexamethasone
url http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000400007
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