TLR4 knockout ameliorates streptozotocin-induced osteoporosis in a mouse model of diabetes.

Type 1 diabetes mellitus (T1DM) is characterized by hyperglycemia manifesting as insufficient insulin. Toll-like receptor-4 (TLR4) has been implicated in diabetic osteoporosis. We established streptozotocin (STZ)-induced diabetic mouse model and examined the relevant osteoporosis factors in different experimental groups, the WT-CON group, WT-STZ group, KO-CON group and KO-STZ group, respectively. No obvious protection of TLR4 deletion was shown in mice with diabetes. There was no obvious difference in the body weight or blood glucose concentration between WT-STZ group and KO-STZ group. However, TLR4 deletion reduced the receptor activator of NF-κB ligand (RANKL)-induced osteoclast differentiation. Furthermore, TLR4 knockout attenuated STZ-induced diabetic osteoporosis via inhibiting osteoblasts and pre-inflammation factors mediated by the NF-κB pathway. TLR4 deletion ameliorated STZ-induced diabetic osteoporosis in mice, and TLR4 may be used as a potential therapeutic target for the treatment of diabetic osteoporosis.