Effect of lentivirus-mediated lactoferrin transporter on osteoporotic fracture healing in rats

Abstract

Objective To investigate the effect of lentivirus-mediated lactoferrin transporter (LF) on the healing of osteoporotic fracture in rats. Methods Fifty SD rats were randomly divided into control group and observation group. Ovariectomy was used to establish osteoporosis model group. Lentiviruses overexpressing LF were injected into the fracture site in the observation group, and equal volume empty carrier lentivirus were injected into the fracture site in the control group. Eight weeks after injection, the expression of LF, bone protection element (OPG) and receptor activator of nuclear factor κB ligand (RANKL) proteins was analyzed by Western blotting. Bone mineral density (BMD), trabecular volume (BV), tissue volume (TV), average trabecular thickness (Tb.Th) and average number of trabeculae (TB.N) were measured by micro-CT. Three points bending test was used to determine the biomechanical parameters of the fracture site. Results Compared to the control group (0.69±0.16, 0.30±0.12 and 0.88±0.20), the expression levels of LF, OPG and RANKL proteins in the fracture site of rats in the observation group (1.17±0.31, 1.25±0.18 and 1.10±0.15) were significantly increased (t=2.965, 2.183 and 3.018 respectively, P<0.01). BMD, BV, TV, Tb.Th and Tb.N in the observation group were significantly higher than those in the control group (t=4.019, 3.183, 2.195, 3.012 and 3.091 respectively, P<0.05). The biomechanical parameters (maximum load, elastic load, stiffness and maximum deflection) of fracture site in the observation group were significantly higher than those in the control group (t=3.691, 2.985, 3.911 and 2.198 respectively, P<0.01)]. Conclusion Lentiviral-mediated LF expression in osteoporotic fracture can significantly promote osteoblast differentiation, promote bone growth and fracture healing, and improve bone quality. Key words: Lactoferrin; Osteoporotic fracture; Healing; Lentivirus