Role of PLF in Muscle Remodeling Following Injury

Abstract

INTRODUCTION: Periostin like factor, PLF, is expressed during embryogenesis, while in adults it is expressed after injury. In mouse PLF is expressed in heart, lung and bone in response to mechanical overloading, exposure to cigarette smoke, and fracture respectively. Together these findings suggest that PLF plays a role in remodeling of tissue following injury. To study the role of PLF in remodeling, muscle tissues obtained from the innovative model of Upper Extremity‐Work‐Related Musculoskeletal Disorder (Barbe et al., 2003) were examined for PLF expression.APPROACH: Sprague Dawley rats performed a High Repetition High Force (HRHF) voluntary reaching and pulling task, with a food pellet reward. Task entailed pulling a lever at a target rate of 4 reaches/min with 60% max grip force for 2hrs/day, 3dys/wk, for up to 12 wks. Forelimb muscles were subjected to immunostaining and Western blot analysis for PLF.RESULT: PLF protein was markedly upregulated in the muscle fibers and satellite cell of the preferred limb of animals exposed to HRHF task. Western blot analysis showed expression of PLF with task performance. Controls showed no expression of PLF in muscle.CONCLUSION: The expression of PLF in muscles fibers and satellite cells of muscles undergoing remodeling and reorganization suggests that PLF plays a significant role in maintenance and repair of muscle after repetitive loading or injury.