Prevention of glucocorticoid induced bone changes with beta-ecdysone

Beta-ecdysone (beta Ecd) is a phytoecdysteroid found in the dry roots and seeds of the asteraceae and achyranthes plants, and is reported to increase osteogenesis in vitro. Since glucocorticoid (GC) excess is associated with a decrease in bone formation, the purpose of this study was to determine if treatment with beta Ecd could prevent GC-inauced osteoporosis. Two-month-old male Swiss-Webster mice (n = 8-10/group) were randomized to either placebo or slow release prednisolone pellets (3.3 mg/kg/day) and treated with vehicle control or beta Ecd (0.5 mg/kg/day) for 21 days. GC treatment inhibited age-dependent trabecular gain and cortical bone expansion and this was accompanied by a 30-50% lower bone formation rate (BFR) at both the endosteal and periosteal surfaces. Mice treated with only beta Ecd significantly increased bone formation on the endosteal and periosteal bone surfaces, and increased cortical bone mass were their controls to compare to GC alone. Concurrent treatment of beta Ecd and GC completely prevented the GC-induced reduction in BFR, trabecular bone volume and partially prevented cortical bone loss. In vitro studies determined that beta Ecd prevented the GC increase in autophagy of the bone marrow stromal cells as well as in whole bone. In summary, beta Ecd prevented GC induced changes in bone formation, bone cell viability and bone mass. Additional studies are warranted of beta Ecd for the treatment of GC induced bone loss. (c) 2015 Elsevier Inc. All rights reserved.