Evaluation of cytokines in protective effect of docosahexaenoic acid in experimental achilles tendinopathy rat model induced with type-1 collagenase

Background We aimed to investigate the effectiveness of docosahexaenoic acid (DHA) as a treatment for Achilles tendinopathy (AT) induced with type-I collagenase in rats and compare it with collagen. Methods The AT model was induced with type I collagenase, and animals were randomly assigned to groups. Group 1:AT, Group 2: Collagen (7.2 mg/kg/day), Group 3:DHA (300 mg/kg/day), and Group 4:DHA (100 mg/kg/day). Right tendons of Group1 were used as a healthy control (HC). Oral treatments were applied for eight weeks. Serum tumor necrosis factor-alpha(TNF-alpha), matrix metalloproteinase-13 (MMP-13), and interleukin-1 beta(IL-1 beta) concentrations were determined by ELISA. Tendon samples were taken for histopathological evaluation and examined immunohistochemically with antibodies specific for Col1A1, TNF-alpha, MMP-13, IL-1 beta, and nitric oxide synthase-2(NOS-2). The ultimate tensile force (UTF) yield force(YF) and stiffness were measured by biomechanical assessments. Results UTF,YF and stiffness values were increased in all treatment groups compared to the AT control, a significant increase was found in Group 2 (p < 0.05). There was severe degeneration of tendon cells in the AT control. The tendon cells in samples from Groups 2-3 were less degraded, and this was statistically significant (p < 0.05). TNF-alpha, MMP-13, IL-1 beta, and NOS-2 expressions were significantly higher in the AT control compared to the HC. In all treatment groups, their concentrations were lower than in the AT control. Serum TNF-alpha, MMP-13, and IL-1 beta levels were lower in all treatment groups (Especially in Group3 (p < 0.001)) compared to Group1. Conclusion The efficacy of high-dose DHA as a treatment for AT was investigated from biochemical, histopathological, and biomechanical perspectives. The results showed that DHA could be an alternative treatment compound to collagen.

Journal

CONNECTIVE TISSUE RESEARCH

Year

2022

Volume

63

Issue

4

Pages

393-405

ISSN

0300-8207

eISSN

1607-8438

DOI

10.1080/03008207.2021.1982915

WoS UID

WOS:000705376100001