Stress resistance and lifespan extension of Caenorhabditis elegans enhanced by peptides from mussel ( Mytilus edulis ) protein hydrolyzate

Bioactive peptides derived from mussels have multiple healthcare functions. Herein, we aimed to examine the effects of mussel peptide preparation on lifespan, stress resistance, apoptosis and aging in Caenorhabditis elegans. Lifespan was determined by counting the number of surviving nematodes daily. ROS level and lipofuscin were measured using a fluorescent microscope. The mussel protein was prepared and hydrolyzed, and then fractionated by ultrafiltration. The fraction (<3 kDa) was purified by gel filtration to obtain the bioactive peptides, and the peptide sequences included in the fractions were identified, which were mostly composed of peptides with <20 amino acid residues. Mussel peptides treatment was found to significantly increase oxidative stress resistance and extend the lifespan of C. elegans. Moreover, this treatment also reduced endogenous ROS level and aging pigments accumulation in C. elegans as well as apoptosis. Collectively, these findings demonstrated that mussel peptides could contribute to healthspan(definition) extension of C. elegans through regulating mRNA expression of daf-2 and daf-16. These results highlighted the important role of mussel peptides for food and pharmaceutical industries to develop new nutraceuticals and functional foods.