Evaluation and Comparison of the Effects of mature Silkworm (Bombyx Mori) and Silkworm Pupae Extracts on Schwann Cell Proliferation and Axon Growth: An in vitro study

Abstract Mature silkworms (Bombyx mori) and their pupae contain a variety of growth factors and proteins such as bombyrin that can be used in many repair processes. Due to its appropriate repair qualities, the silkworm has been explored for use in nerve regeneration. First silkworm (Bombyx Mori) and silkworm Pupae Extracts were prepared. Then the concentration and type of amino acids and proteins in the extracts were evaluated by Bradford assay, SDS-page, and LC-MS/MS. Also, the regenerative potential of extracts for improving Schwann cell proliferation and axon growth was examined by MTT, SEM, and NF200 immunostaining. According to the results of the Bradford test, the total protein content of pupae extract was almost twice that of mature worm extract. Also, SDS-PAGE analysis revealed numerous proteins and growth factors such as bombyrin and laminin in extracts that are involved in the repair of the nervous system. Based on LC-MS/MS results, the number of amino acids in pupae extract was higher than in mature silkworm extract. It was found that the proliferation of Schwann cells at a concentration of 0.25 in both extracts was higher than the concentrations of 0.01 and 0.05. When using both extracts on DRGs, an increase in length and number was observed in axons.The findings of this study demonstrated that extracts obtained from adult silkworms, especially pupae, can play an effective role in Schwann cell proliferation and axonal growth, which can be strong evidence for nerve regeneration and consequently repairing peripheral nerve damage.