TY - JOUR
T1 - Hyaluronic acid injections protect patellar tendon from detraining-associated damage
AU - Frizziero, Antonio
AU - Salamanna, Francesca
AU - Giavaresi, Gianluca
AU - Ferrari, Andrea
AU - Martini, Lucia
AU - Marini, Marina
AU - Veicsteinas, Arsenio
AU - Maffulli, Nicola
AU - Masiero, Stefano
AU - Fini, Milena
PY - 2015/9/1
Y1 - 2015/9/1
N2 - Introduction: Having previously demonstrated that detraining affects patellar tendon (PT) proteoglycan content and collagen fiber organization, we undertook the present study with two aims: to improve knowledge on the adaptation of PT and its enthesis to detraining from a histological and histomorphometric point of view, and to investigate the hypothesis that repeated peri-patellar injections of hyaluronic acid (HA) on detrained PT may reduce and limit detrained associated-damage. Methods: Twenty-four male Sprague-Dawley rats were divided into 3 groups: Untrained (n=6), Trained (n=6) (10 wks-treadmill) and Detrained (n=12). In the detrained rats, the left tendon was untreated while the right tendon received repeated peri-patellar injections of either HA or saline (NaCl). Structure and morphology of PTs (modified Movin score, tear density, collagen type I and III) and enthesis (cell morphology, chondrocyte cluster formation, tidemark integrity, matrix staining and vascularization) were evaluated. Results: The left PT and enthesis of the Detrained groups showed altered structure and morphology with the highest Movin score values, the highest percentage of collagen III and the lowest of collagen I; the lowest score values were observed in the Trained and Detrained-HA groups. Detrained-NaCl PTs showed the highest collagen III and the lowest collagen I values with respect to Detrained-HA PTs. Conclusion: This study strengthens previously published data showing the alteration in tendon and enthesis morphology due to discontinuation of training,and provides new data showing that treatment with HAis effective in the maintenance of the structural properties of PT and enthesis in Detrained rats. Such beneficial effects could play a significant role in the management of conservative and rehabilitation strategies in athletes that change type, intensity and duration of training.
AB - Introduction: Having previously demonstrated that detraining affects patellar tendon (PT) proteoglycan content and collagen fiber organization, we undertook the present study with two aims: to improve knowledge on the adaptation of PT and its enthesis to detraining from a histological and histomorphometric point of view, and to investigate the hypothesis that repeated peri-patellar injections of hyaluronic acid (HA) on detrained PT may reduce and limit detrained associated-damage. Methods: Twenty-four male Sprague-Dawley rats were divided into 3 groups: Untrained (n=6), Trained (n=6) (10 wks-treadmill) and Detrained (n=12). In the detrained rats, the left tendon was untreated while the right tendon received repeated peri-patellar injections of either HA or saline (NaCl). Structure and morphology of PTs (modified Movin score, tear density, collagen type I and III) and enthesis (cell morphology, chondrocyte cluster formation, tidemark integrity, matrix staining and vascularization) were evaluated. Results: The left PT and enthesis of the Detrained groups showed altered structure and morphology with the highest Movin score values, the highest percentage of collagen III and the lowest of collagen I; the lowest score values were observed in the Trained and Detrained-HA groups. Detrained-NaCl PTs showed the highest collagen III and the lowest collagen I values with respect to Detrained-HA PTs. Conclusion: This study strengthens previously published data showing the alteration in tendon and enthesis morphology due to discontinuation of training,and provides new data showing that treatment with HAis effective in the maintenance of the structural properties of PT and enthesis in Detrained rats. Such beneficial effects could play a significant role in the management of conservative and rehabilitation strategies in athletes that change type, intensity and duration of training.
KW - Detraining
KW - Enthesis
KW - Hyaluronic acid
KW - Rats
KW - Tendon
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U2 - 10.14670/HH-11-605
DO - 10.14670/HH-11-605
M3 - Article
C2 - 25767092
AN - SCOPUS:84938579285
VL - 30
SP - 1079
EP - 1088
JO - Histology and Histopathology
JF - Histology and Histopathology
SN - 0213-3911
IS - 9
ER -