Zhang Hua, Zhou Zhenlei, Luo Jingwen, Hou Jiafa
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.
BMC Vet Res. 2015 Apr 8;11:86. doi: 10.1186/s12917-015-0398-5.
Corticosterone is one of the most crucial glucocorticoids (GCs) in poultry. Our previous study shows that corticosterone can retard the longitudinal growth of bones by depressing the proliferation and differentiation of chondrocytes in broilers. The present study was designed to investigate whether corticosterone affect the development of chondrocytes and the synthesis of collagen in vitro. The chondrocytes were isolated from proximal tibial growth plates of 6-week-old broiler chickens and cultured with different doses of corticosterone for 48 h. Then the cell viability, alkaline phosphatase (ALP) activity and the expression of parathyroid hormone-related peptide (PTHrP) and type X collagen (Col X) were detected.
At 10(-9)-10(-6) M concentration, corticosterone significantly inhibited the viability and differentiation of chondrocytes, as indicated by decreases in ALP and type X collagen expression. Conversely, there was completely opposite effect at 10(-10) M. In addition, the expression of PTHrP was significantly downregulated at 10(-6) M and 10(-8) M, and was upregulated at 10(-10) M.
The results suggested that corticosterone regulated chicken chondrocytes performance depending on its concentration with high concentrations inhibiting the viability and differentiation of chondrocytes and light concentrations promoting them, and these roles of corticosterone may be in part mediated through PTHrP.
皮质酮是家禽体内最关键的糖皮质激素（GCs）之一。我们之前的研究表明，皮质酮可通过抑制肉鸡软骨细胞的增殖和分化来延缓骨骼的纵向生长。本研究旨在探讨皮质酮在体外是否会影响软骨细胞的发育及胶原蛋白的合成。从6周龄肉鸡的胫骨近端生长板分离软骨细胞，并用不同剂量的皮质酮培养48小时。然后检测细胞活力、碱性磷酸酶（ALP）活性以及甲状旁腺激素相关肽（PTHrP）和X型胶原蛋白（Col X）的表达。
在10⁻⁹ - 10⁻⁶ M浓度下，皮质酮显著抑制软骨细胞的活力和分化，表现为ALP和X型胶原蛋白表达降低。相反，在10⁻¹⁰ M时则出现完全相反的效果。此外，PTHrP的表达在10⁻⁶ M和10⁻⁸ M时显著下调，在10⁻¹⁰ M时上调。
结果表明，皮质酮根据其浓度调节鸡软骨细胞的性能，高浓度抑制软骨细胞的活力和分化，低浓度促进其活力和分化，皮质酮的这些作用可能部分通过PTHrP介导。
