Local administration of Trolox, a vitamin E analog, reduced tendon adhesion in a chicken model of flexor digitorum profundus tendon injury

Abstract

SummaryBackgroundHand flexor tendon injuries are compromised with tendon adhesion. Tendon adhesion forms between flexor tendon and tendon sheath, reduces the range of motion of fingers, and affects their function. Oxidative stress is increased in flexor tendon after injury and might play a role in tendon adhesion formation. Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), a water-soluble analog of vitamin E, is antioxidative. Trolox reduced oxidative stress and the expression of fibrotic cytokines in the bile gut ligation animal model. Vitamin C and Trolox are strong antioxidants, but they might also have prooxidant properties. The prooxidant properties of vitamin C and Trolox are different. In this study, our aim was to determine the effect of Trolox in reducing tendon adhesion formation.MethodsFlexor digitorum profundus tendon injury was induced in 54 Kai-Mei Chicken according to a well-established protocol. After wound closure, an injection of 50 μL saline, 10mM Trolox, or 100mM Trolox was administered into the wound area. At 2 weeks or 6 weeks after the surgery, chicken feet were harvested for gliding test, high-resolution ultrasound measurement on a fibrotic area, and histology.ResultsAt Week 2 after the surgery, Trolox has no effect on the flexion angle and gliding resistance, whereas a significant improvement was observed in the flexion angle and gliding resistance in the Trolox-treated groups at Week 6. However, no dose response was observed. In the ultrasound measurement, there was no significant difference in the fibrotic mass in the Trolox-treated group as compared to the saline group at Week 2. At Week 6, fibrotic mass was significantly reduced in both Trolox-treated groups. From the histological examination, the Trolox-treated groups presented a higher cellularity at Week 2 as compared to the saline group, and reduced fibrosis and adhesion at Week 6.ConclusionOur results suggest that local administration of Trolox can reduce tendon adhesion, and a higher dose of Trolox did not have negative effects.Clinical SignificanceTrolox solution might be feasible to reduce tendon adhesion via intraoperative injection at the wound area during tendon repair.

Hydrogen peroxide induced tendinopathic changes in a rat model of patellar tendon injury

“…More extensive extrinsic healing was observed in H 2 O 2 treatment groups, which resulted in less organized and aligned collagen fibers with peritendinous adhesion. It may help to explain why antioxidant supplementation can reduce tendon adhesion in flexor tendon injuries model . Apart from the sources of healing cells, origins of neovascularization were also better revealed at this sectioning plane.…”

Does methylene blue reduce adhesion during the healing process after tendon repair?

“…[ 28 ] In another study, local vitamin E analogue was shown to reduce postoperative adhesion by antioxidant and antifibrotic effects in an experimental chicken model with flexor digitorum profundus tendon injury. [ 12 ] Reduced postoperative adhesion was shown in another study where collagen-elastin matrix was used to prevent postoperative adhesion in an experimental rabbit model undergoing flexor tendon repair. [ 18 ]…”

“…When experimental studies on flexor digitorum profundus tendon adhesion are examined, it is seen that chicken models are frequently used as subjects. [12,13] We preferred to use chickens for reasons such as low cost and the adequate accommodation conditions in the animal laboratory where we carried out the study. Therefore, in this study, we aimed to biomechanically and histopathologically investigate the effects of MB on preventing postoperative adhesion in chickens undergoing full-thickness flexor tendon incision.…”

Quercetin reduces tendon adhesion in rat through suppression of oxidative stress

“…Many methods have been used to prevent tendon adhesion, such as the improvement of surgical technology, the use of barriers, systemic or local application of drugs and chemicals. Although these methods can reduce adhesions to some extent, the residual or recurrent adhesions still need to be resolved [5][6][7][8].…”