Pleiotrophin as an osteocyte-derived osteogenic mediator of mechanical loading: evidence from in vivo and in vitro studies

2016 Fiscal Year Final Research Report

• Project/Area Number: 26462291
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Orthopaedic surgery
• Research Institution: Shiga University of Medical Science
• Principal Investigator: Imai Shinji 滋賀医科大学, 医学部, 教授 (90283556)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 力学的骨形成調節 / 骨芽細胞 / 骨細胞 / pleiotrophin

Outline of Final Research Achievements

In agreement with previous reports, the skeletal structure of the PTN knockout mice developed normally. However, a subtle growth retardation of the weight-bearing bones was observed upon adulthood, suggesting a link to physical activity. Adult PTN deficient mice were characterized by low turnover and osteopenia, as well as resistance to exercise/immobilization-dependent bone remodeling. PTN was localized around osteocytes and their processes in vivo and furthermore, osteocytic PTN expression was upregulated by mechanical loading in vitro. PTN did not have any effect on human osteoclast formation or resorption in vitro. Our results suggest that PTN is an osteocyte-derived factor that can mediate the osteogenic effects of mechanical loading on bone. Thus, PTN could be a novel promising target to enhance bone maintenance and regeneration.

Free Research Field

整形外科学