Immunization with Na+/K+ ATPase DR peptide prevents bone loss in an ovariectomized rat osteoporosis model.

Immunization with Na+/K+ ATPase DR peptide prevents bone loss in an ovariectomized rat osteoporosis model. Biochem Pharmacol. 2018 Aug 19;: Authors: Xiong S, Yang X, Yan X, Hua F, Zhu M, Guo L, Wu Z, Bian JS Abstract Osteoporosis is characterized by decreased bone strength and microarchitectural deterioration of bone tissue leading to an increase in bone fracture. Here we report a new agent named DR peptide, a conserved sequence of Na+/K+ ATPase (NKA), can be used to prevent osteoporosis. Our results showed that immunization with DR peptide conjunct with Keyhole limpet hemocyanin (DR-KLH) significantly strengthened trabecular bone and improved bone mineral density of femur and the 5th lumbar in the ovariectomized (OVX) rats when compared with those in OVX rats immunized with KLH alone. To study the underlying mechanisms, anti-DR antibody (DR-Ab) and IgG were purified from the serum of rats immunized with DR-KLH or KLH alone in OVX rats. We found that DR-Ab had no significant effects on the proliferation of osteoclasts precursors, but it alleviated the inhibitory effect of H2O2 on the expression of osteogenic marker genes, Runx2, alkaline phosphatase and bone sialoprotein. DR-Ab also reversed the loss of collagen and the reduced bone nodule formation caused by H2O2 treatment. Knockdown of NKA with siRNA transfection reduced osteoblast differentiation and rendered the osteoblasts more vulnerable to oxidative challenge. Immunostaining a...
Source: Biochemical Pharmacology - Category: Drugs & Pharmacology Authors: Tags: Biochem Pharmacol Source Type: research