title: Eccentric Training for Tendon Healing After Acute Lesion: A Rat Model.
abstract: BACKGROUND
  The tendon is a dynamic entity that remodels permanently. Platelet-rich plasma (PRP) injection has been shown to have a beneficial effect on tendon healing after lesion in rats. Furthermore, eccentric exercise seems to improve the mechanical quality of the tendon.
  
  
  OBJECTIVE
  A combination of PRP injection and eccentric training might be more effective than either treatment alone.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Adult male rats were anesthetized, an incision was performed in the middle of their left patellar tendon and an injection of physiological fluid (PF) or homologous PRP was randomly made at the lesion level. The rats were then divided into 2 groups: the eccentric group, undergoing eccentric training 3 times a week, and the untrained group, without any training. Thus, 4 groups were compared. After 5 weeks, the tendons were removed and their ultimate tensile strength and energy were measured. Tendons were frozen for proteomic analyses when all biomechanical tests were completed. Statistical analysis was performed with linear mixed effect models.
  
  
  RESULTS
  No significant difference was found between the treatments using PF injection or PRP injection alone. However, the value of the ultimate tensile force at rupture was increased by 4.5 N (108% of control, P = .006) when eccentric training was performed. An intragroup analysis revealed that eccentric training significantly improved the ultimate force values for the PRP group. Proteomic analysis revealed that eccentric training led to an increase in abundance of several cytoskeletal proteins in the PF group, while a decrease in abundance of enzymes of the glycolytic pathway occurred in the PRP-treated groups, indicating that this treatment might redirect the exercise-driven metabolic plasticity of the tendon.
  
  
  CONCLUSIONS
  Eccentric training altered the metabolic plasticity of tendon and led to an improvement of injured tendon resistance regardless of the treatment injected (PF or PRP).
  
  
  CONCLUSIONS
  This study demonstrates the necessity of eccentric rehabilitation and training in cases of tendon lesion regardless of the treatment carried out.
authors.affiliation: Physical Medicine, Rehabilitation and Sports Traumatology Department, SportS2, FIFA Medical Centre of Excellence, University and University Hospital of Liège, Liège, Belgium.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Kaux
authors.affiliation: Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Liège, Liège, Belgium.
authors.forename: Vincent
authors.initials: V
authors.lastname: Libertiaux
authors.affiliation: GIGA Neurosciences, University of Liège, Liège, Belgium.
authors.forename: Pierre
authors.initials: P
authors.lastname: Leprince
authors.affiliation: Laboratory for the Analysis of Medicines (LAM), Department of Pharmacy, CIRM, University of Liège, Liège, Belgium.
authors.forename: Marianne
authors.initials: M
authors.lastname: Fillet
authors.affiliation: Department ARGENCO, University of Liège, Liège, Liège, Belgium.
authors.forename: Vincent
authors.initials: V
authors.lastname: Denoel
authors.affiliation: Physical Medicine, Rehabilitation and Sports Traumatology Department, SportS2, FIFA Medical Centre of Excellence, University and University Hospital of Liège, Liège, Belgium.
authors.forename: Clémence
authors.initials: C
authors.lastname: Wyss
authors.affiliation: Department of Laboratory Hematology, University and University Hospital of Liège, Liège, Liège, Belgium.
authors.forename: Christelle
authors.initials: C
authors.lastname: Lecut
authors.affiliation: Department of Laboratory Hematology, University and University Hospital of Liège, Liège, Liège, Belgium.
authors.forename: André
authors.initials: A
authors.lastname: Gothot
authors.affiliation: Department of Clinical Chemistry, University and University Hospital of Liège, Belgium.
authors.forename: Caroline
authors.initials: C
authors.lastname: Le Goff
authors.affiliation: Physical Medicine, Rehabilitation and Sports Traumatology Department, SportS2, FIFA Medical Centre of Excellence, University and University Hospital of Liège, Liège, Belgium.
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Croisier
authors.affiliation: Physical Medicine, Rehabilitation and Sports Traumatology Department, SportS2, FIFA Medical Centre of Excellence, University and University Hospital of Liège, Liège, Belgium.
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Crielaard
authors.affiliation: Animal Facility, University of Liège, Liège, Belgium.
authors.forename: Pierre
authors.initials: P
authors.lastname: Drion
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005081:Exercise Therapy / Q000379:methods*; D008297:Male; D017847:Patellar Ligament / Q000293:injuries / Q000502:physiology; D053657:Platelet-Rich Plasma; D011506:Proteins / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D012421:Rupture; D013708:Tendon Injuries / Q000378:metabolism / Q000503:physiopathology* / Q000628:therapy*; D013718:Tensile Strength; D014945:Wound Healing / Q000502:physiology*
chemical_list: D011506:Proteins
keywords: PRP; biomechanics; eccentric; platelet-rich plasma; proteomics; tendon