Background
Cardiovascular disorders (CVDs) are causally linked to thrombosis inside veins or arteries, a leading cause of global mortality. Commercial antithrombotic drugs have numerous limitations; hence the need to explore novel therapeutics for CVDs is imperative.
Purpose
This study demonstrates the antithrombotic mechanism and in vivo safety of a novel 7-mer peptide therapeutic prototype, generated through computational analysis combining two thrombin-binding segments of the anticoagulant phospholipase A2 (NnPLA2-I) derived from the Indian cobra Naja naja venom.
Methods
The thrombin-binding regions of a cobra venom phospholipase A₂ (NnPLA2-I) were predicted by in silico (computational) analysis. A novel low-molecular-weight peptide (775.85 Da) consisting of seven amino acid residues (7-mer) by combining two segments of thrombin-binding residues from NnPLA2-I was synthesized. The blood-thinning effect of the custom peptide was tested, and its effectiveness was compared to that of well-known commercial products. The in vivo anticoagulation and preclinical safety of this peptide were evaluated in a rodent model.
Results
The in silico analysis demonstrated enhanced thrombin inhibition relative to factor Xa by the 7-mer synthetic peptide, which was validated using biochemical experiments and spectrofluorometric titration analysis. This custom peptide demonstrated dose-dependent inhibition of in vitro blood coagulation; however, it showed no hemolytic activity, cytotoxicity, or cell cycle arrest in mammalian cells, as assessed by flow cytometry. The 7-mer synthetic peptide binds to the catalytic site and additional sites on thrombin, highlighting differences in the mechanisms of thrombin inhibition by this peptide, commercial anticoagulant hirudins, and argatroban. The intravenous administration of this 7-mer synthetic peptide in Wistar rats exhibited dose-dependent anticoagulant effects, and inhibited k-carrageenan-induced thrombus formation in rat tails. A single-dose in vivo toxicity investigation revealed that this 7-mer synthetic peptide was non-toxic, indicating its preclinical safety.
Conclusion
The therapeutic and preventive applications of this 7-mer synthetic peptide prototype for addressing thrombotic issues appear viable. Nonetheless, additional research is necessary to secure this peptide-based anticoagulant drug prototype from the laboratory to commercial availability.
Dutta, S., Das, D., Chattopadhyay, P. et al. Mechanism of Anticoagulation, Inhibition of In Vivo Thrombus Formation, and Assessment of Preclinical Safety of a Snake Venom Phospholipase A2 Enzyme-inspired New Antithrombotic Custom Peptide. Int J Pept Res Ther 32, 54 (2026). https://doi.org/10.1007/s10989-026-10832-4
