Fucus vesiculosus extract inhibits the proteolytic activity and gene expression of matrix metalloproteinases in Atlantic salmon (Salmo salar L.)

Abstract

Fucoidans are sulfated fucose-rich polysaccharides found in macroalgae. Multiple biological functions have been attributed to fucoidans including inhibitory activity against matrix metalloproteinases (MMPs). A recent study showed that kidney and blood remains left in the abdominal cavity after gutting had a significant negative effect on gaping and fillet firmness in Atlantic salmon (Salmo salar L.). The authors hypothesized that one reason could be that MMPs from kidney and blood remains break down the connective tissue in Atlantic salmon fillets. The objectives of this study were to investigate the presence of MMPs in Atlantic salmon kidney and the inhibitory effect of a Fucus vesiculosus extract (FVE) on the proteolytic activity and gene expression of MMPs in Atlantic salmon. The inhibitory effect of FVE was compared to the inhibitory effect of the synthetic broad-spectrum MMP inhibitor marimastat. In this study, we found that FVE inhibits the proteolytic activity of MMP-1, MMP-2, MMP-9, and MMP-13 in Atlantic salmon kidney as well as MMP-2 gene expression in Atlantic salmon liver. Although the inhibitory effect of FVE on the proteolytic activity of MMPs is small compared to the inhibitory effect of marimastat, both FVE and marimastat inhibit 80% of the DQ-gelatin breakdown caused by Atlantic salmon kidney at a concentration of 0.1 mg mL−1. This indicates that FVE may also be capable of inhibiting other proteinases present in Atlantic salmon kidney. Overall, our findings suggest that FVE could be used in the fish processing industry to limit collagenase and gelatinase activity, thus reducing the connective tissue degradation in Atlantic salmon fillets.