Effect of Desmodium renifolium on ovariectomized rat model of osteoporosis via BMP-2/Smads signaling pathway

Abstract

This study aimed to investigate the effect of Desmodium renifolium(Linn.) Schindl on ovariectomized rat model of osteoporosis and explore the underlying mechanism. Rats were randomized into a sham group, a model group, a Xianlin Gubao group, and low-, medium-, and high-dose D. renifolium groups. Bilateral oophorectomy was performed in other groups except sham group(removal of bilateral peri-ovarian adipose tissue). The sham group and model group were administrated with equal volume of 0.5% CMC-Na, Xianlin Gubao group with Xianlin Gubao, and D. renifolium groups with different concentrations of alcoholic extract of D. renifolium once a day for 14 weeks. The body weight of rats were recorded during the experiment. The levels of estradiol(E_2), 1,25-dihydroxyvitamin D_3 [1,25(OH)_2D_3], calcium(Ca), and phosphorus(P) in serum were determined after the administration. The femur microstructure was analyzed via micro-CT. RT-PCR and Western blot were employed to respectively determine the mRNA and protein levels of bone morphogenetic protein 2(BMP-2), Runt-related transcription factor 2(Runx2), and osterix(OSX) in the tibia of rats. The results indicated that D. renifolium significantly inhibited the weight growth, improved the uterus appearance, elevated the levels of E_2, Ca, P, and 1,25(OH)_2D_3 in serum, increased the number and reduced the fracture of bone trabeculae, ameliorated the bone microstructure parameters, and up-regulated the mRNA and protein levels of BMP-2, Runx2, and OSX. All the results demonstrated that D. renifolium had significant protective effect on the ovariectomized rat model of osteoporosis by regulating the BMP-2/Smads signaling pathway.