Perinatal Exposure to Vitamin A Differentially Regulates Chondrocyte Growth and the Expression of Aggrecan and Matrix Metalloprotein Genes in the Femur of Neonatal Rats

摘要: Vitamin A (VA) and its active form, retinoic acid (RA), are regulators of skeletal development. In the present study, we investigated if maternal VA intake during pregnancy lactation, as well direct oral supplementation neonates with + RA (VARA) in early life, alters neonatal bone formation chondrocyte gene expression. Offspring dams fed 3 levels (marginal, adequate, supplemented) for 10 wk were studied at birth (P0) postnatal day 7 (P7). One-half newborns received an supplement VARA on P1, P4, P7. Tissues collected P0 6 h after last dose Pup plasma liver retinol concentrations increased by both (P < 0.01). Although did not affect mineralization assessed von Kossa staining, newborn femur length was 0.05). hypertrophic zone only VA-marginal pups, close to that from VA-adequate dams, suggesting caused a catching up growth limited low intake. Maternal diet alter type X nor II collagen mRNA. However, VARA-treated pups VA-supplemented had reduced mRNA aggrecan, major component cartilage matrix, matrix metalloproteinase (MMP)13, which catalyzes degradation aggrecan collagens. These results suggest moderately high combined can reduce ratio aggrecan:MMP, may unfavorably