Calcium reduces vitamin D and glucocorticoid receptors in the visceral fat of obese male rats.
Rats overfed during lactation show higher visceral adipose tissue (VAT) mass and metabolic dysfunctions at adulthood. As both vitamin D and glucocorticoids change adipogenesis, parameters related to metabolism and action of these hormones in the adipocyte can be altered in rats raised in small litters (SL). We also studied the antiobesity effects of high calcium diet since it decreases visceral fat in obesity models. On postnatal day (PN) 3, litter size was adjusted to 3pups/dam (SL) to induce overfeeding. Control litters (NL) remained with 10pups/dam until weaning. From PN120 to PN180, half of the SL rats were fed standard chow (SL) and the other half was fed a calcium-supplemented chow (SL-Ca, 10g CaCO3/kg). Both SL groups were heavier and hyperphagic when compared with the NL group; however, SL-Ca rats ate less than SL. SL-Ca rats had decreased VAT mass and adipocyte size, associated with lower hypothalamic NPY content, VAT fat acid synthase content and leptinemia. At PN120, SL rats had increased plasma 25(OH)D3, Cyp27b1 mRNA and glucocorticoid receptor (GR-α) in the VAT, but lower vitamin D receptor (Vdr) mRNA. At PN180, Cyp27b1 and GR-α remained higher, while Vdr normalized in SL rats. SL-Ca rats had normal VAT Cyp27b1 and GR-α, but lower Vdr Thus, higher body mass and glucocorticoid receptors in the VAT of SL rats are normalized by calcium-enriched diet, and Vdr expression in this tissue is reduced, suggesting a possible role of glucocorticoids and vitamin D in calcium action in the adipocyte.
Laboratory of Endocrine PhysiologyDepartment of Physiological Sciences, Roberto Alcantara Gomes Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
E P S
EP
Conceição
Laboratory of Endocrine PhysiologyDepartment of Physiological Sciences, Roberto Alcantara Gomes Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
E G
EG
Moura
Laboratory of NeurophysiologyDepartment of Physiological Sciences, Roberto Alcantara Gomes Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
A C
AC
Manhães
Laboratory of Endocrine PhysiologyDepartment of Physiological Sciences, Roberto Alcantara Gomes Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
J C
JC
Carvalho
Laboratory of Endocrine PhysiologyDepartment of Physiological Sciences, Roberto Alcantara Gomes Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
J L
JL
Nobre
Laboratory of Endocrine PhysiologyDepartment of Physiological Sciences, Roberto Alcantara Gomes Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
E
E
Oliveira
Laboratory of Endocrine PhysiologyDepartment of Physiological Sciences, Roberto Alcantara Gomes Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil pclisboa@uerj.br.
P C
PC
Lisboa
D000818:Animals; D002118:Calcium / Q000494:pharmacology / Q000627:therapeutic use*; D019587:Dietary Supplements; D004195:Disease Models, Animal; D050152:Intra-Abdominal Fat / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D009765:Obesity / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D017208:Rats, Wistar; D011965:Receptors, Glucocorticoid / Q000378:metabolism*; D014807:Vitamin D / Q000378:metabolism*
D011965:Receptors, Glucocorticoid; D014807:Vitamin D; D002118:Calcium
NPY; calcium supplementation; corticosterone; overnutrition; vitamin D3