[SCT-OGP fusion protein expression and its potential role as osteoporosis therapy]

Osteoporosis is a disease of bone metabolic disorder, the incidence of which increases sharply in old people. Calcitonin (CT) is a peptide hormone containing 32 amino acid that can inhibit osteoclasts activity. Osteogenic Growth Peptide (OGP) is a peptide hormone with 14 amino acid. It is an autocrine mitogen for osteoblastic and firbroblastic cells which has anabolic activiy. Six SCT and OGP DNA segments were chemically synthesized and ligated into a yeast expression vector pPIC9. The recombinant plasmid was transformed into pichia pastoris GS115. Finally, we got two stable SCT-OGP high expression clones after screening. Purifed protein can stimulate the proliferation of osteoblastic and fibroblastic cells, and also stimulate serum ALP activity and decrease serum calcium level using mice as animal models, demonstrating its potential role in oteoporosis therapy.