Human Achilles tendon glycation and function in diabetes
Christian Couppé, Rene Brüggebusch Svensson, Mads Kongsgaard, Vuokko Kovanen, Jean-Francois Grosset, Ole Snorgaard, Jesper Bencke, Jytte Overgaard Larsen, Thomas Bandholm, Tomas Møller Christensen, Anders Boesen, Ida Carøe Helmark, Per Aagaard, Michael Kjaer, Stig Peter Magnusson, Christian Couppé, Rene Brüggebusch Svensson, Mads Kongsgaard, Vuokko Kovanen, Jean-Francois Grosset, Ole Snorgaard, Jesper Bencke, Jytte Overgaard Larsen, Thomas Bandholm, Tomas Møller Christensen, Anders Boesen, Ida Carøe Helmark, Per Aagaard, Michael Kjaer, Stig Peter Magnusson
Abstract
Diabetic patients have an increased risk of foot ulcers, and glycation of collagen may increase tissue stiffness. We hypothesized that the level of glycemic control (glycation) may affect Achilles tendon stiffness, which can influence gait pattern. We therefore investigated the relationship between collagen glycation, Achilles tendon stiffness parameters, and plantar pressure in poorly (n = 22) and well (n = 22) controlled diabetic patients, including healthy age-matched (45-70 yr) controls (n = 11). There were no differences in any of the outcome parameters (collagen cross-linking or tendon stiffness) between patients with well-controlled and poorly controlled diabetes. The overall effect of diabetes was explored by collapsing the diabetes groups (DB) compared with the controls. Skin collagen cross-linking lysylpyridinoline, hydroxylysylpyridinoline (136%, 80%, P < 0.01) and pentosidine concentrations (55%, P < 0.05) were markedly greater in DB. Furthermore, Achilles tendon material stiffness was higher in DB (54%, P < 0.01). Notably, DB also demonstrated higher forefoot/rearfoot peak-plantar-pressure ratio (33%, P < 0.01). Overall, Achilles tendon material stiffness and skin connective tissue cross-linking were greater in diabetic patients compared with controls. The higher foot pressure indicates that material stiffness of tendon and other tissue (e.g., skin and joint capsule) may influence foot gait. The difference in foot pressure distribution may contribute to the development of foot ulcers in diabetic patients.
Keywords: Achilles tendon mechanics; diabetes; enzymatic and nonenzymatic collagen cross-linking; foot ulcer.
Copyright © 2016 the American Physiological Society.
Source: PubMed