Adipose-Derived Stem Cells Improve Collagenase-Induced Tendinopathy in a Rat Model

Background:Tendinopathy is a common and highly prevalent musculoskeletal disorder characterized by repetitive activity-related pain and focal tendon tenderness. Histopathologically, tendinopathic tissue mainly shows degenerative changes. Therefore, tendinopathy is not affected by anti-inflammatory therapies. A novel approach, including a stem cell–based therapy, may be beneficial for its treatment.Purpose/Hypothesis:The purpose of this study was to evaluate the effects of adipose-derived stem cells (ASCs) on tendon healing in a rat tendinopathy model. The hypothesis was that ASC transplantation would improve degeneration in collagenase-induced tendinopathy.Study Design:Controlled laboratory study.Methods:Sixteen F344/NSlc rats underwent collagenase injection into the Achilles tendon to induce tendinopathy. At 1 week after collagenase injection, 8 rats received ASCs (ASC group) and 8 received phosphate-buffered saline alone (PBS group). Animals were sacrificed at 4 or 12 weeks after ASC administration, and...