Effects of zoledronic acid combined with metformin on bones of DB/DB mice

Abstract Background Diabetic patients are prone to osteoporosis. Both zoledronic acid and metformin have certain anti-osteoporotic effects.Here we explore the anti-osteoporotic effect of the combination of two drugs. Methods 12-week-old DB/DB mice were divided into DB/DB group, zoledronic acid group,metformin group and zoledronic acid combined with metformin group, WT mice were treated as WT group alone. The mice were killed after ten weeks. Then using Micro-ct to scan the tibia and stain the contralateral lower limbs with HE. Results First, we find that the body weight of DB/DB mice treated with metforminre stable and their blood glucose reduce.Second, after HE staining,it is observed under light microscope that there are a large number of adipocytes, few bone trabeculae, few osteoblasts and osteoclasts in the bone marrow cavity in the DB/DB group compared with the WT group, while the number of bone trabeculae in the combined treatment group is higher than that in the zoledronic acid group or metformin group, and a large number of blood cells, blood vessels and adipocytes are found in the bone marrow cavity of the combined drug group compared with the zoledronic acid group. Last, the results of Micro-ct present that, comparing with the DB/DB group and the metformin group,SMI is significantly different(P < 0.05);comparing with the DB/DB group and the zoledronic acid group,Tb.N,Tb.Sp,Conn.D and SMI are significantly different(P < 0.05);BV/TV, Conn.D, SMI, BMD, Tb.N and Tb.Sp in the combination treatment group are significantly difference than those in the DB/DB group(P < 0.05). Conclusion In term of the bone mass lose of DB/DB mice, the treatment of the zoledronic acid combined with metformin outperforms that using the zoledronic acid or metformin only.