Local treatment with ascorbic acid accelerates recovery of post-sutured Achilles tendon in male Wistar rats

Abstract

Tendon rupture is a very frequent accident involving average people and high-performance athletes. Clinical studies describe tendon recovery as a painful and slow process involving different biochemical and histological events. Ascorbic acid (AA) is a potent antioxidant as well as an important cofactor for collagen synthesis. In the current study, we evaluated if local treatment with AA is able to promote tendon repair in tenotomized rats. Animals were submitted to Achilles tendon rupture followed by surgical suture. Control and AA groups received in loco injection of saline solution (0.9% NaCl) and 30 mM AA, respectively. Histological and functional recovery of Achilles tendon tissue was evaluated at 7, 14, and 21 days post-surgery. Hematoxylin/eosin staining and collagen fluorescence analysis showed intense disarrangement of tendon tissue in the saline group. Tenotomized animals also showed hypercellularity in tendon tissue compared with non-tenotomized animals. The Achilles functional index (AFI) showed a significant decrease of tendon functionality in tenotomized animals at 7, 14, and 21 days post-surgery. AA accelerated tissue organization and the recovery of function of the Achilles tendons. The beneficial effect of AA treatment was also observed in the organization of the collagen network. Data presented in the current work showed that in loco treatment with AA accelerated the recovery of injured Achilles tendon post-surgery.

Vitamin C in orthopedic practices: Current concepts, novel ideas, and future perspectives

“…3 Several studies have examined the impact of vitamin C supplementation on collagen synthesis and tendon health/healing. 43,44 Vitamin C potentiates tendon healing by increasing the collagen fibril diameter and the number of fibroblasts at the injured site, as well as by promoting local angiogenesis. 4 In addition, vitamin C has been shown to reduce peritendinous adhesions in an animal model.…”

“…45 Animal studies have investigated the effect of vitamin C on healing of the Achilles tendon (AT). 43,44 A study by Omerğlu et al 43 tested the effect of high-dose vitamin C supplementation on AT healing in rats, and they found that vitamin C accelerated tendon healing. A study by Dincel et al 4 sought to determine the effect of high-dose vitamin C or hyaluronic acid (HA) on AT healing in rats, and they discovered that both vitamin C and HA, in isolation but more so in combination, led to higher tendon tensile strength measurements when compared to the control.…”

“…As a result, nutritional and exercise interventions have been proposed as a means of inducing collagen synthesis to strengthen tendons and mitigate injury 3 . Several studies have examined the impact of vitamin C supplementation on collagen synthesis and tendon health/healing 43,44 . Vitamin C potentiates tendon healing by increasing the collagen fibril diameter and the number of fibroblasts at the injured site, as well as by promoting local angiogenesis 4 .…”

“…Animal studies have investigated the effect of vitamin C on healing of the Achilles tendon (AT) 43,44 . A study by Omerğlu et al 43 tested the effect of high‐dose vitamin C supplementation on AT healing in rats, and they found that vitamin C accelerated tendon healing.…”

“…A study by Dincel et al 4 sought to determine the effect of high‐dose vitamin C or hyaluronic acid (HA) on AT healing in rats, and they discovered that both vitamin C and HA, in isolation but more so in combination, led to higher tendon tensile strength measurements when compared to the control 4 . In 2019, Souza et al 44 reported that vitamin C led to faster AT tissue organization, better organization of the collagen network, and improved ultimate tendon functionality compared to the control in rats. Although the beneficial effect of vitamin C on AT healing is generally supported by rat laboratory studies, randomized studies must be conducted on humans before vitamin C can be considered a legitimate nutritional intervention for patients following AT injury.…”