Intermittent parathyroid hormone (1–34) application regulates cAMP-response element binding protein activity to promote the proliferation and osteogenic differentiation of bone mesenchymal stromal cells, via the cAMP/PKA signaling pathway

Abstract

Abstract. The potential effects of intermittent parathyroid hormone (1-34) ] administration on bone formation have previously been investigated. A number of studies have suggested that the cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) pathway is associated with PTH-induced osteogenic differentiation. However, the precise signaling pathways and molecular mechanism by which PTH (1-34) induces the osteogenic differentiation of bone mesenchymal stromal cells (BMSCs) remain elusive. The purpose of the present study was to investigate the mechanism underlying the effect of intermittent PTH (1-34) application on the proliferation and osteogenic differentiation of BMSCs. BMSCs were randomly divided into four groups, as follows: Osteogenic medium (control group); osteogenic medium and intermittent PTH (1-34); osteogenic medium and intermittent PTH (1-34) plus the adenylyl cyclase activator forskolin; and osteogenic medium and intermittent PTH (1-34) plus the PKA inhibitor H-89. A cell proliferation assay revealed that PTH (1-34) stimulates BMSC proliferation via the cAMP/PKA pathway. Furthermore, reverse transcription-quantitative polymerase chain reaction, alkaline phosphatase activity testing and cell examination using Alizarin Red S staining demonstrated that PTH (1-34) administration promotes osteogenic differentiation and mineralization, mediated by the cAMP/PKA pathway. Crucially, the results of western blot analyses suggested that PTH (1-34) treatment and, to a greater degree, PTH (1-34) plus forskolin treatment caused an increase in phosphorylated cAMP response element binding protein (p-CREB) expression, but the effect of PTH on p-CREB expression was blocked by H-89. In conclusion, the current study demonstrated that intermittent PTH (1-34) administration regulates downstream proteins, particularly p-CREB, in the cAMP/PKA signaling pathway, to enhance the proliferation, osteogenic differentiation and mineralization of BMSCs.

Retracted: In vivo and in vitro effects of PTH1‐34 on osteogenic and adipogenic differentiation of human bone marrow‐derived mesenchymal stem cells through regulating microRNA‐155

“…PTH1‐34 has been clinically approved for treating OP through promoting osteogenic differentiation of hBMSCs . Moreover, miRNAs have been reported to play important roles in bone‐related diseases, such as OP, by means of controlling differentiation of osteoblasts .…”

Regulation of body length and bone mass by Gpr126/Adgrg6

“…To further confirm whether Gpr126 regulates osteoblast differentiation and mineralization by modulation of the cAMP-CREB signaling pathway, we used forskolin (FSK), an activator of adenylyl cyclase, and PTH(1-34), an osteoporosis drug, both of which can induce bone formation and mineralization by promoting cAMP-CREB signaling (21). Our results showed that the intracellular cAMP levels were decreased in Osx-Cre;Gpr126 fl/fl mouse osteoblasts, while FSK substantially increased the intracellular cAMP levels in Osx-Cre; Gpr126 fl/fl mouse osteoblast cells (Fig.…”

Effects of intermittent treatment with parathyroid hormone (PTH) on osteoblastic differentiation and mineralization of mouse induced pluripotent stem cells in a 3D culture model

“…32 In patients with severe periodontitis, regeneration of showed that the intermittent administration of PTH promoted expression of Sp7 mRNA via cAMP/PKA signaling in bone marrow stromal cells of rats. 35 We also observed significant cAMP production in miPS-EB-derived cells already at 10 to 30 minutes after PTH treatment (unpublished data). The result of the present study indicated the generation of cAMP upon PTH treatment over a 14day period (Figure 1).…”