Wound healing at the body wall of the sea cucumber Apostichopus japonicus by Chinese herbal treatment

Abstract

The leading cause of death for sea cucumbers in aquaculture is damage to the body wall. Large-scale use of antibiotics to treat such wounds is undesirable because this treatment leaves a drug residue in the animal's body as well as posing increased pathogen resistance in the environment. In this study, both naturally and artificially occurring wound sea cucumber were used as the experimental animals. Compound Chinese herbal medicines were then selected and evaluated for wound healing effects. The results showed that Chinese herbal medicine mixtures I (Angelica dahurica, Geosaurus, Rhus chinensis and Dark plum fruit), II (Angelica dahurica, Geosaurus and Taraxacum mongolicum Hand) and III (Angelica dahurica, Geosaurus, Taraxacum mongolicum Hand, Rhus chinensis and Dark plum fruit) significantly improved wound healing of artificially injured sea cucumbers. After 1 week of treatment, histological analysis showed that the epidermal layer was completely restored, indistinguishable from the control. Cyclin B, Protease inhibitor Epi11 and PCSK9 expression in immune coelomocytes showed a tendency to increase at first and then decrease at different time points of herbal treatment. Results of companion treatment trials for naturally wounded sea cucumbers showed that after 1 week in the treatment group, the skin ulcer areas of sea cucumbers were reduced, and the survival rate was significantly improved. The results of this study provide a scientific basis for the treatment and prevention of sea cucumber skin ulcerations and body wall damage. This treatment may provide an important natural healing modality for sea cucumbers in an aquaculture system.