Novel Hyp-Gly-containing antiplatelet peptides from collagen hydrolysate after simulated gastrointestinal digestion and intestinal absorption
Bioactive components underlying the antiplatelet activity of CH ingestion have not been clarified. This study aimed to identify antiplatelet peptides from CH after simulated gastrointestinal digestion and intestinal absorption. Four antiplatelet peptides containing Hyp-Gly (OG) sequence including OG, Hyp-Gly-Glu (OGE), Pro-Gly-Glu-Hyp-Gly (PGEOG) and Val-Gly-Pro-Hyp-Gly-Pro-Ala (VGPOGPA) were successfully identified. All four peptides exhibited antiplatelet activity, but OGE and PGEOG exerted stronger activity than OG and VGPOGPA. IC50 value of OGE and PGEOG was 1.076 mM and 1.167 mM, respectively. These four antiplatelet peptides could survive simulated gastrointestinal digestion and be absorbed intact by Caco-2 cells. Further, plasma stability experiments showed that OG and OGE had a good stability in human plasma, but PGEOG and VGPOGPA had a relatively poor stability. In vivo studies indicated that OG and OGE were present in blood after oral administration of CH. Meanwhile, OGE exerted a significant in vivo anti-thrombotic activity after ingestion. The present study clarifies the antiplatelet components underlying CH and highlights the potential application of CH or these four peptides as functional foods to combat thrombosis by inhibiting platelet aggregation.