Modulation in Wistar rats of blood corticosterone compartmentation by sex and a cafeteria diet.
In the metabolic syndrome, glucocorticoid activity is increased, but circulating levels show little change. Most of blood glucocorticoids are bound to corticosteroid-binding globulin (CBG), which liver expression and circulating levels are higher in females than in males. Since blood hormones are al...
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Format: | Article |
Language: | English |
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Public Library of Science (PLoS)
2013-01-01
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Series: | PLoS ONE |
Online Access: | http://europepmc.org/articles/PMC3579843?pdf=render |
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author | María del Mar Romero Fredrik Holmgren-Holm Maria del Mar Grasa Montserrat Esteve Xavier Remesar José Antonio Fernández-López Marià Alemany |
author_facet | María del Mar Romero Fredrik Holmgren-Holm Maria del Mar Grasa Montserrat Esteve Xavier Remesar José Antonio Fernández-López Marià Alemany |
author_sort | María del Mar Romero |
collection | DOAJ |
description | In the metabolic syndrome, glucocorticoid activity is increased, but circulating levels show little change. Most of blood glucocorticoids are bound to corticosteroid-binding globulin (CBG), which liver expression and circulating levels are higher in females than in males. Since blood hormones are also bound to blood cells, and the size of this compartment is considerable for androgens and estrogens, we analyzed whether sex or eating a cafeteria diet altered the compartmentation of corticosterone in rat blood. The main corticosterone compartment in rat blood is that specifically bound to plasma proteins, with smaller compartments bound to blood cells or free. Cafeteria diet increased the expression of liver CBG gene, binding plasma capacity and the proportion of blood cell-bound corticosterone. There were marked sex differences in blood corticosterone compartmentation in rats, which were unrelated to testosterone. The use of a monoclonal antibody ELISA and a polyclonal Western blot for plasma CBG compared with both specific plasma binding of corticosterone and CBG gene expression suggested the existence of different forms of CBG, with varying affinities for corticosterone in males and females, since ELISA data showed higher plasma CBG for males, but binding and Western blot analyses (plus liver gene expression) and higher physiological effectiveness for females. Good cross-reactivity to the antigen for polyclonal CBG antibody suggests that in all cases we were measuring CBG. The different immunoreactivity and binding affinity may help explain the marked sex-related differences in plasma hormone binding as sex-linked different proportions of CBG forms. |
first_indexed | 2024-12-22T13:50:14Z |
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institution | Directory Open Access Journal |
issn | 1932-6203 |
language | English |
last_indexed | 2024-12-22T13:50:14Z |
publishDate | 2013-01-01 |
publisher | Public Library of Science (PLoS) |
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spelling | doaj.art-e175adf510b24292a45bf768df89e58c2022-12-21T18:23:41ZengPublic Library of Science (PLoS)PLoS ONE1932-62032013-01-0182e5734210.1371/journal.pone.0057342Modulation in Wistar rats of blood corticosterone compartmentation by sex and a cafeteria diet.María del Mar RomeroFredrik Holmgren-HolmMaria del Mar GrasaMontserrat EsteveXavier RemesarJosé Antonio Fernández-LópezMarià AlemanyIn the metabolic syndrome, glucocorticoid activity is increased, but circulating levels show little change. Most of blood glucocorticoids are bound to corticosteroid-binding globulin (CBG), which liver expression and circulating levels are higher in females than in males. Since blood hormones are also bound to blood cells, and the size of this compartment is considerable for androgens and estrogens, we analyzed whether sex or eating a cafeteria diet altered the compartmentation of corticosterone in rat blood. The main corticosterone compartment in rat blood is that specifically bound to plasma proteins, with smaller compartments bound to blood cells or free. Cafeteria diet increased the expression of liver CBG gene, binding plasma capacity and the proportion of blood cell-bound corticosterone. There were marked sex differences in blood corticosterone compartmentation in rats, which were unrelated to testosterone. The use of a monoclonal antibody ELISA and a polyclonal Western blot for plasma CBG compared with both specific plasma binding of corticosterone and CBG gene expression suggested the existence of different forms of CBG, with varying affinities for corticosterone in males and females, since ELISA data showed higher plasma CBG for males, but binding and Western blot analyses (plus liver gene expression) and higher physiological effectiveness for females. Good cross-reactivity to the antigen for polyclonal CBG antibody suggests that in all cases we were measuring CBG. The different immunoreactivity and binding affinity may help explain the marked sex-related differences in plasma hormone binding as sex-linked different proportions of CBG forms.http://europepmc.org/articles/PMC3579843?pdf=render |
spellingShingle | María del Mar Romero Fredrik Holmgren-Holm Maria del Mar Grasa Montserrat Esteve Xavier Remesar José Antonio Fernández-López Marià Alemany Modulation in Wistar rats of blood corticosterone compartmentation by sex and a cafeteria diet. PLoS ONE |
title | Modulation in Wistar rats of blood corticosterone compartmentation by sex and a cafeteria diet. |
title_full | Modulation in Wistar rats of blood corticosterone compartmentation by sex and a cafeteria diet. |
title_fullStr | Modulation in Wistar rats of blood corticosterone compartmentation by sex and a cafeteria diet. |
title_full_unstemmed | Modulation in Wistar rats of blood corticosterone compartmentation by sex and a cafeteria diet. |
title_short | Modulation in Wistar rats of blood corticosterone compartmentation by sex and a cafeteria diet. |
title_sort | modulation in wistar rats of blood corticosterone compartmentation by sex and a cafeteria diet |
url | http://europepmc.org/articles/PMC3579843?pdf=render |
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