Defibrotide, a Polydeoxyribonucleotide Derivative, Shown to Act via Blood Vessel Lining

Ulutin and colleagues, writing in Folia haematologica in 1988, describe how defibrotide, a drug made from polydeoxyribonucleotide (a chain of DNA building blocks) extracted from bovine lung, works against blood clotting. The paper summarizes findings from animal studies and human subjects rather than presenting a single new experiment.

The authors report that defibrotide acts mainly by changing the behavior of endothelial cells, the cells lining blood vessels. It increased production and release of t-PA, a protein involved in breaking down clots, and corrected a defect seen in a test of vascular function called the Cuff test. It also raised levels of a clot-preventing substance called PGI2, raised platelet c-AMP while lowering MDA and TXA2 (molecules tied to platelet activation), and reduced platelet activation, observed both by a surface method and under the microscope. The compound also increased protein C and factor V, and worked together with heparin. Unlike most antithrombotic drugs, it did not alter standard clotting tests in either animals or people, suggesting a different mode of action from existing treatments.

As a summary of prior findings, the paper does not provide new sample sizes, doses, or detailed methods, so the strength of evidence behind each individual claim cannot be independently judged from this abstract alone.