Abstract:

BACKGROUND: Several researches have shown that hypoxia can lead to the healing of fracture delayed or non healing, and reduce bone density, which will improve the incidence of osteoporosis and fracture.
OBJECTIVE: To investigate the effects of hypoxia on the proliferation, differentiation and gene expression of osteoblasts cultured in vitro.
METHODS: The cranium from a newborn Wistar rat was collected and osteoblasts were extracted by trypsogen-collagenase sequential digestion method. The cells were subcultured in vitro and identified. The reproductive rate of osteoblasts was tested by MTT assay. Alkaline phosphatase activity of osteoblasts was detected by nitrophenylphosphate method. Bone gamma-carboxyglutamic-acid-containing proteins (BGP) and type Ⅰ collagen expression were measured by reverse transcription-PCR method.
RESULTS AND CONLUSION: Our studies revealed that hypoxia could inhibit the proliferation of osteoblasts and reduce alkaline phosphatase activity as well as decrease the expression of BGP mRNA and type Ⅰ collagen mRNA in a time-dependent manner. These findings suggest that hypoxia can inhibit the proliferation and differentiation of osteoblasts cultured in vitro and decrease the expression of BGP mRNA and type Ⅰ collagen, which will decrease osteogenic ability and promote the incidence of osteoporosis.