| Osteoporosis is a systemic bone disease characterized by the destruction of bone microstructure and the decrease of bone mass.The trophic metabolic bone mass loss is the predecessor of osteoporosis.Oleanolic acid(OA)is a kind of pentacyclic triterpenoids widely existing in various plants.It is also the main active component of Fructus Ligustrum and has abundant pharmacological effects.The mechanism of oleanolic acid on osteoporosis was studied through network pharmacology,and the effect of oleanolic acid on bone loss model related to oxidative stress in vivo and in vitro was combined to explore an anti-osteoporosis action mode of oleanolic acid.Methods:Gene Cards and Stitch were used to identify oleanolic acid targets,and NCBI,Genecards and Dis Ge Net databases were used to mine osteoporosis related targets.The overlapping targets of oleanolic acid and osteoporosis were used as candidate targets for protein-protein interaction through String database.GO analysis and KEGG analysis of genes and genomes were performed through DAVID database.In addition,the top 16 targets in the protein interaction network were used for molecular docking.In vivo experiments,D-galactose(10 g/kg/d)and low-calcium diet(0.1%calcium concentration)were used to build animal models.Meanwhile,13 week-old Kunming mice(5 groups,6 mice in each group)were administrated with low,medium and high concentrations of oleanolic acid(20 mg/kg,40 mg/kg,80 mg/kg,respectively).The test period was 20 days.After 20 days,liver and kidney malondialdehyde(MDA),superoxide dismutase(SOD),urinary calcium creatinine,calcium balance,bone coefficient,bone dry/wet ratio,bone mineral density of femur,BMD and other indexes of mice in each group were detected.MC3T3-E1 cells were treated with different concentrations of oleanolic acid(50,20,10 μM,respectively)under oxidative stress.CCK-8,ALP activity and OPG protein secretion were detected.Conclusion: The results of network pharmacology show that oleanolic acid can treat osteoporosis by multi-target and multi-pathway.In vivo experiment results showed that oleanolic acid can improve the REDOX homeostasis in vivo by reducing MDA content in liver and kidney tissue and increasing SOD activity,and significantly inhibit the oxidative stress of the body.Besides,oleanolic acid can promote the balance of calcium,increase the diaxial moisture ratio and bone index,and regulate bone density and bone volume fraction to improve the overall bone microstructure.The results of in vitro experiments showed that oleanolic acid could enhance the proliferation of osteoblasts,increase the content of OPG protein,and increase the OPG/RANKL ratio,so as to prevent osteoporosis. |
