Novel Peptide Motifs Containing Asp-Glu-Gly Target P2Y12 and Thromboxane A2 Receptors to Inhibit Platelet Aggregation and Thrombus Formation

Antiplatelet activity and toxicity profile of novel phosphonium salts derived from Michael reaction

In this work, five novel phosphonium salts derived from the Michael reaction were screened for their antiplatelet activity. Our findings revealed that compounds 2a, 2b, 2c, and 2d significantly inhibit platelet aggregation triggered by ADP or collagen (P < 0.001). Notably, compound 2c inhibited the arachidonic acid pathway (P < 0.001). Moreover, the selected compounds reduce CD62-P expression and inhibit GPIIb/IIIa activation. The interactions of the active compounds with their targets, ADP and collagen receptors, P2Y12 and GPVI respectively were investigated in silico using molecular docking studies. The results revealed a strong affinity of the active compounds for P2Y12 and GPVI. Additionally, cytotoxicity assays on platelets, erythrocytes, and human embryonic kidney HEK293 cells showed that compounds 2a, 2c and 2d were non-toxic even at high concentrations. In summary, our study shows that phosphonium salts can have strong antiplatelet power and suggests that compounds 2a, 2c and 2d could be promising antiplatelet agents for the management of cardiovascular diseases.

Enrichment of antiplatelet peptides and removal of fishy odor from silver carp skin collagen hydrolysates by macroporous resins: pH value of loading sample affects the peptides separation

Enrichment of antiplatelet peptides from silver carp skin collagen hydrolysates (CH) was studied using macroporous resins. Static adsorption showed that XAD-16 resin was the suitable resin due to its high adsorption capacity. The dynamic desorption of CH was studied on XAD-16 resin by ethanol gradient elution. Interestingly, pH value of loading sample had a great impact on the peptides separation. Results revealed that the yield and the antiplatelet activity of Ethl-20% fraction were highest at loading sample pH 6.0. The antiplatelet peptides were enriched in the 20% ethanol fraction with IC₅₀ 2.03 mg/mL compared to IC₅₀ of CH, 4.7 mg/mL. Besides, the Ethl-20% fraction had a weakest fishy odor. Moreover, a series of peptides containing Hyp-Gly or Pro-Gly were identified from Ethl-20% fraction, which contributed to the antiplatelet activities. This study provided a simple and efficient method for large-scale separation enrichment of antiplatelet peptides as functional foods from CH.

Structural Insights on Hyp-Gly-Containing Peptides as Antiplatelet Compounds through Topomer CoMFA and CoMSIA Analysis

Increasing evidence has shown collagen hydrolysate involves a variety of bioactivities. In our previous study, multiple antiplatelet peptides containing Hyp/Pro-Gly were identified in collagen hydrolysates from Salmo salar and silver carp skin and exhibited anti-thrombosis activity without bleeding risks in vivo. However, the relationship between structure and activity remains unknown. We performed 3D-QSAR studies on 23 Hyp/Pro-Gly-containing peptides in which 13 peptides were reported before. CoMFA, Topomer CoMFA and CoMSIA analyses were used to generate the QSAR models. Topomer CoMFA analysis showed a q² value of 0.710, an r² value of 0.826, an r²_pred value of 0.930, and the results showed that Hyp instead of Pro was more important for improving the antiplatelet activity. CoMSIA analysis showed a q² value of 0.461, an r² value of 0.999, and an r²_pred value of 0.999. Compared with the electrostatic field and hydrogen bond donor field, the steric field, hydrophobic field and hydrogen bond receptor field have great influence on the activity of antiplatelet peptides. The predicted peptide EOGE exhibited antiplatelet activity induced by ADP, and inhibited thrombus formation (300 μmol/kg bw) without bleeding risks. Combined results of these studies indicate that OG-containing peptides had a potential to be developed into an effective specific medical food in the prevention of thrombotic diseases.