Hydrolyzed fish proteins reduced activation of caspase-3 in H2O2 induced oxidative stressed liver cells isolated from Atlantic salmon (Salmo salar).

K. B. Øysæd,M. Espe,J. He,L. Chen,E. Holen,F. Provan,J. Seliussen

doi:10.1186/s40064-015-1432-6

Abstract

Hydrolyzed fish proteins (H-pro) contains high concentrations of free amino acids and low molecular peptides that potentially benefit health. The following study aimed to test whether the water soluble phase of H-pro could reduce apoptosis and inflammation in primary liver cells isolated from Atlantic salmon following H2O2 provoked oxidative stress. Cells were grown as monocultures or co-cultured with head kidney cells to assess possible cross talk in inflammation and metabolism during treatments. Cells were grown in media with or without H-pro for 2 days before being stressed with 200 µM H2O2 then harvested 24 h post exposure. Both treatments were compared to the respective treatments without H2O2 supplementation. Oxidative stressed cells had increased activation of caspase-3, but supplementation with H-pro in the media prior to the oxidative stress reduced caspase-3 activation. In conclusion, free amino acids and low molecular weight peptides from H-pro attenuated oxidative stress, and made cells able to withstand apoptosis after H2O2 provoked oxidative stress.

Highlights

Cells have to respond quickly to changes in the environment and signal the correct cascade of signals to survive
We previously showed that supplementation of taurine to primary liver cells isolated from Atlantic salmon improved viability and reduced activation of p-38 Mitogen Activating Phospho Kinase (MAPK) (Espe and Holen 2013)
Liver cells grown both as mono- and co-cultured together with head kidney cells showed no difference in gene expression of caspase-3 due to culture conditions (p = 0.13), but cells grown in the cL15 media stressed with H2O2 had significantly higher gene expression of caspase-3 than the stressed cells grown in media supplemented with hydrolyzed proteins (H-pro) (p = 0.039)

Summary

Introduction

Cells have to respond quickly to changes in the environment and signal the correct cascade of signals to survive. The water soluble part of hydrolyzed proteins (H-pro) contains free amino acids and several non-protein nitrogen compounds that may have the potential to improve health in fish (Espe and Lied 1999; Liaset et al 2003; Andersen et al 2015). The current study aimed to test whether H-pro, containing several low molecular weight nitrogen compounds and free amino acids could reduce oxidative stress signaling through reduction in the activation of the MAPK cascade resulting in caspase-3 activation. Both liver and head kidney cells were used with the aim to investigate the inflammatory response and oxidative signals following H2O2 provoked oxidative stress in a co-culture approach as described (Holen et al 2014)

Methods

Results

Conclusion