This study is to explore underlying mechanism of skin wound healing by snakehead fish soup using rat and cell models. We assessed skin wound changes after administering wild and farmed snakehead fish soup intragastrically, then using CCK-8 and scratch tests to evaluate cell proliferation and migration, last assessed vessel tubule formation by HUVEC cells. The results showed that the skin wound healing rates of rats after 14 days of intragastrical administration of farmed and wild snakehead fish soup were 52.71% and 57.76%, respectively, which were substantially greater than the control group (39.84%). With the administration of the soups, the collagen tissue on the skin wound was more homogenous and thicker, and type I collagen was denser. Additionally, interleukin-6 level in rat serum during wound healing was significantly lower, while cyclin-D1 and fibroblast growth factor-2 levels were higher. Furthermore, the soups (particularly at 50 μg/mL) significantly increased the proliferation and migration rates of both the HACAT and NIH3T3 cells, and considerably promoted the tubule formation of HUVEC cells. The findings confirm that the soup can promote skin wound healing and the underlying mechanism involves multiple roles including anti-inflammation, cell proliferation, vessel tubule formation, and collagen expression.

Traditionally, fish carcass is headed and gutted to prepare a skin-on fillet in surimi production. In this study, tail and/or belly of grass carp carcass were further cut off in the filleting step. Yield, composition, gelling properties and aroma profile of surimi as affected by filleting methods were investigated by SDS-PAGE, ELISA, SEM, magnetic resonance imaging (MRI) and electron nose. Cutting tail off increased surimi yield by 14.0%, whereas cutting belly off decreased it by 11.2%. Cutting tail or belly off significantly decreased fat content, but did not change protein content, ash content, cathepsin (B, H and L) contents, nor protein patterns. Both breaking force and whiteness of surimi gel significantly increased after cutting tail off. Cutting belly off slightly increased whiteness of surimi gel. The microstructure of all the surimi gels was compact and uniform, with fractal dimensions (D_f) ranging from 2.81 to 2.85. As for the macrostructure, cutting tail off apparently improved the integrity of surimi gel while cutting belly off did not. Aroma profiles of the surimi prepared under different filleting methods could be clearly distinguished by linear discriminant analysis (LDA). Our results indicate that cutting tail off contribute positively to surimi production.