Anticorps antisclérostine et ostéogenèse imparfaite : évaluation chez la souris oim/oim

Osteogenesis imperfecta (OI) is a genetic disease of type I collagen that particularly affects bone matrix and is manifested by numerous fractures, skeletal deformities and small size. Its treatment aims to inhibit bone destruction or stimulate osteogenesis. The oim/oim mouse (osteogenesis imperfecta mouse) is an animal model of severe OI in humans (type 3). For 9 weeks, oim/oim mice received an antibody that neutralizes sclerostin (Scl-Ab), an endogenous inhibitor of the osteoblastic WNT pathway. Scl-Ab therapeutic potential has been highlighted in animal models of postmenopausal osteoporosis. In the oim/oim mouse, we observed that Scl-Ab has no effect on small size, but it increases the bone mass and the mechanical strength of vertebrae and long bones. These effects are accompanied by a significant reduction in fracture number. The skeletal parameters analyzed vary between male and female mice, particularly with age, and the anti-fracture effect of Scl-Ab was more pronounced in male than female oim/oim mice.