Jean-François Kaux1, Vincent Libertiaux2, Pierre Leprince3, Marianne Fillet4, Vincent Denoel5, Clémence Wyss1, Christelle Lecut6, André Gothot6, Caroline Le Goff7, Jean-Louis Croisier1, Jean-Michel Crielaard1, Pierre Drion8. 1. Physical Medicine, Rehabilitation and Sports Traumatology Department, SportS2, FIFA Medical Centre of Excellence, University and University Hospital of Liège, Liège, Belgium. 2. Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Liège, Liège, Belgium. 3. GIGA Neurosciences, University of Liège, Liège, Belgium. 4. Laboratory for the Analysis of Medicines (LAM), Department of Pharmacy, CIRM, University of Liège, Liège, Belgium. 5. Department ARGENCO, University of Liège, Liège, Liège, Belgium. 6. Department of Laboratory Hematology, University and University Hospital of Liège, Liège, Liège, Belgium. 7. Department of Clinical Chemistry, University and University Hospital of Liège, Belgium. 8. Animal Facility, University of Liège, Liège, Belgium.
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. HYPOTHESIS: A combination of PRP injection and eccentric training might be more effective than either treatment alone. STUDY DESIGN: 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. CONCLUSION: 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). CLINICAL RELEVANCE: This study demonstrates the necessity of eccentric rehabilitation and training in cases of tendon lesion regardless of the treatment carried out.
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. HYPOTHESIS: A combination of PRP injection and eccentric training might be more effective than either treatment alone. STUDY DESIGN: 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. CONCLUSION: 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). CLINICAL RELEVANCE: This study demonstrates the necessity of eccentric rehabilitation and training in cases of tendon lesion regardless of the treatment carried out.
Authors: Sabah N Rezvani; Anne E C Nichols; Robert W Grange; Linda A Dahlgren; P Gunnar Brolinson; Vincent M Wang Journal: J Appl Physiol (1985) Date: 2021-02-11