Effect of dietary chitosan supplement on muscle inflammation and recovery after cardiotoxin-induced injury

Abstract

Chitosan is a natural and non-toxic polymer that has a wide range of pharmaceutical application, including drug carrier, wound dressing and neuroprotective agents. This study aimed to evaluate the effect of chitosan on the inflammatory response and muscle recovery after acute injury. Adult male Wistar rats were randomly divided into 2 major groups: control intact and an injury group. The injury group was further divided into vehicle and chitosan treatment. After 1 week of treatment, injury was induced in tibialis anterior (TA) by cardiotoxin injection. At day 1 and day 3 post-injury, rats were sacrificed and contractile functions of TA muscles were measured. After 1 day post-injury, there was a significant reduction in force production in both the vehicle-treated (~42%) and chitosan-treated (~54%) groups compared to the control. These reduction in force, however, were recovered to control value in both injury groups by day 3 post injury, with chitosan-treated group (~14%) showed better improvement than that in the vehicle-treated group (~23%). This effect was associated with increases damage area and expressions of tumor nuclear factor-a (TNF-a), interleukin-6 (IL-6), interleukin-10 (IL-10), and transforming growth factor- B] (TGF-B]) mRNA level in both injury groups at day 1 post-injury. On day 3 postinjury, however, the level of TNF-α and TGF-β] mRNA were further increased only in the chitosan-treated group, while IL-6 and IL-10 mRNA expressions were unaffected in both injury groups. Taken together, these results suggest that chitosan treatment could enhance the inflammatory response but had a small effect on muscle recovery following cardiotoxin-induced injury.