Ethanolic extract of Dalbergia sissoo promotes rapid regeneration of cortical bone in drill-hole defect model of rat.

Leaves of Dalbergia sissoo is known to have protective actions against postmenopausal bone loss in rat. In this study, we have evaluated the fracture healing properties of ethanolic extract (EE) of Dalbergia sissoo leaves. To observe the fracture healing property in the drill-hole injury model, we randomly divided total 32 adult female Sprague Dawley rats (180±200g) into 4 groups: (i) Control operated group; (ii) EE (250mg/kg/day); (iii) EE (500mg/kg/day) and (iv) EE (1000mg/kg/day). The right femora were fractured at the mid-diaphysis region and each group of rats received their respective treatment for 15days. Ethanol extract dose dependently induced bone regeneration at the fracture site assessed by fluorochrome labeling. All of three doses, 250mg/kg/day dose significantly increased bone volume fraction, trabecular thickness, trabecular number, and connectivity density and decreased trabecular separation in bone. Furthermore, the extract induced the expression of osteogenic genes including BMP-2, BMP-4, RunX-2 and COL-1 compared to the control group. The EE improved fracture healing much earlier (day 15) than the normal healing process, as assessed by the increased callus volumes and mineralized nodule formation. This extract is found beneficial in fracture healing of rat.