Corticosteroids and hyaluronic acid effects on four growth factors in tendon tissues of rat rotator cuff injury models / 中国组织工程研究

ABSTRACT

BACKGROUND: Tissue engineering plays an important role in treating rotator cuff injury. Promoting the healing of injured rotator cuff and preventing adhesion by regulating growth factor expression are main functions. OBJECTIVE:To compare the effects of corticosteroids and hyaluronic acid on the expressions of epidermal growth factor (EGF),platelet-derived growth factor (PDGF),transforming growth factor ? (TGF-?) and basic fibroblast growth factor (bFGF) in injured rotator cuff. DESIGN,TIME AND SETTING: The randomized controlled animal experiment was performed at the Animal Experimental Center,School of Medicine,Shanghai Jiao Tong University from July to September 2007. MATERIALS Totally thirty-six Sprague-Dawley (SD) rats were randomly assigned into four groups normal group (n=6),rotator cuff injury group (n=6),hyaluronic acid group (n=12) and corticosteroids group (n=12). METHODS: Full-thickness defects across 50% of the total width (5 mm) of the bilateral infraspinatus tendon were excised. Models of rotator cuff injury were created at the synovium. 0.05 mL hyaluronic acid was injected into the subacromial bursa mucosa in the hyaluronic acid group,whereas 0.05 mL corticosteroids in the corticosteroids group. MAIN OUTCOME MEASURES: At three and six weeks after injury,the infraspinatus were harvested to detect EGF,PDGF,TGF-? and BFGF by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: By using corticosteroids treatment,the expression of EGF remained greater at the six weeks than twofold at the three weeks; the expression of EGF after hyaluronic acid treatment greatly decreased at six weeks (P