GFAP expression in astrocytes of suprachiasmatic nucleus and medial preoptic area are differentially affected by malnutrition during rat brain development.
The aim of the present study was investigate, in young rats, the effects of malnutrition on astrocyte distribution of two hypothalamic regions, the circadian pacemaker suprachiasmatic nucleus (SCN) and the medial preoptic area (MPA). Control rats were born from mothers fed on commercial diet since gestation and malnourished rats from mothers fed on multideficient diet, from the beginning of gestation (GLA group) or from the onset of lactation (LA group). After weaning, pups received ad libitum the same diet as their mothers, and were maintained under a 12/12 h light/dark cycle. The animals were analyzed either at 30-33, or 60-63 days of life. Brain coronal sections (50 microm) were processed to visualize glial fibrillary acidic protein (GFAP) immunoreactivity. Compared to control rats, both malnourished groups of 30 and 60 days exhibited a reduced number of GFAP-immunoreactive astrocytes in the SCN. The total GFAP-immunoreactive area in the SCN of the GLA group differed from the control group at both age ranges analyzed. The GFAP expression as measured by the relative optical density (ROD) exhibited a 50-60% reduction in the MPA in both malnourished groups, compared to controls. The results suggest that malnutrition early in life leads to alterations in gliogenesis or glial cell proliferation in both nuclei, being these alterations greater in the MPA. Compensatory plasticity mechanisms in the GFAP-expression seem to be developed in the astrocyte differentiation process in the SCN, especially when the malnutrition is installed from the lactation.
Mendonça
João Esmeraldo Frota
JE
Centro de Ciências da Saúde, Universidade de Fortaleza, Fortaleza, CE, Brazil.
Vilela
Maria Cristina Ramos
MC
Bittencourt
Heitor
H
Lapa
Raíssa Maria
RM
Oliveira
Francisco Gilberto
FG
Alessio
Maria Luíza Martins
ML
Guedes
Rubem Carlos Araújo
RC
De Oliveira Costa
Miriam Stela Maris
MS
Da Costa
Belmira Lara da Silveira Andrade
BL
D000375:Aging; D000818:Animals; D001253:Astrocytes / Q000737:chemistry*; D001835:Body Weight; D001921:Brain / Q000254:growth & development* / Q000378:metabolism; D002452:Cell Count; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis*; D044342:Malnutrition / Q000378:metabolism*; D009929:Organ Size; D011301:Preoptic Area / Q000737:chemistry* / Q000166:cytology; D051381:Rats; D017208:Rats, Wistar; D013493:Suprachiasmatic Nucleus / Q000737:chemistry* / Q000166:cytology
D005904:Glial Fibrillary Acidic Protein