RESEARCH ARTICLE Inflammatory and Metabolic Alterations of Kager's Fat Pad in Chronic Achilles Tendinopathy Jessica Pingel1☯, M. Christine H. Petersen2,3☯, Ulrich Fredberg4,Søren G. Kjær4, Bjørn Quistorff3, Henning Langberg5, Jacob B. Hansen2* 1 Department of Exercise and Nutrition, University of Copenhagen, Copenhagen, Denmark, 2 Department of Biology, University of Copenhagen, Copenhagen, Denmark, 3 Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark, 4 Diagnostic Centre, Silkeborg Regional Hospital, Silkeborg, Denmark, 5 CopenRehab, Department of Public Health, University of Copenhagen, Copenhagen, Denmark ☯ These authors contributed equally to this work. *
[email protected] Abstract OPEN ACCESS Background Citation: Pingel J, Petersen MCH, Fredberg U, Kjær Achilles tendinopathy is a painful inflammatory condition characterized by swelling, stiffness SG, Quistorff B, Langberg H, et al. (2015) and reduced function of the Achilles tendon. Kager’s fat pad is an adipose tissue located in Inflammatory and Metabolic Alterations of Kager's Fat Pad in Chronic Achilles Tendinopathy. PLoS ONE 10 the area anterior to the Achilles tendon. Observations reveal a close physical interplay be- (5): e0127811. doi:10.1371/journal.pone.0127811 tween Kager’s fat pad and its surrounding structures during movement of the ankle, sug- ’ Academic Editor: Hazel RC Screen, Queen Mary gesting that Kager s fat pad may stabilize and protect the mechanical function of the ankle University of London, UNITED KINGDOM joint. Received: January 19, 2015 Accepted: April 18, 2015 Aim Published: May 21, 2015 The aim of this study was to characterize whether Achilles tendinopathy was accompanied by changes in expression of inflammatory markers and metabolic enzymes in Kager’sfat Copyright: © 2015 Pingel et al.