Di Micco Biagio, Lepretti Marilena, Rota Lidia, Quaglia Ilaria, Ferrazzi Paola, Di Micco Gianluca, Di Micco Pierpaolo
Department of Internal Medicine, Buon Consiglio Fatebenefratelli Hospital of Naples, Italy.
J Transl Med. 2007 Dec 21;5:69. doi: 10.1186/1479-5876-5-69.
Native Factor V is an anticoagulant, but when activated by thrombin, Factor X or platelet proteases, it becomes a procoagulant. Due to these double properties, Factor V plays a crucial role in the regulation of coagulation/anticoagulation balance. Factor V Leiden (FVL) disorder may lead to thrombophilia. Whether a reduction in the activation of Factor V or Factor V Leiden may correct the disposition to thrombophilia is unknown. Therefore we tested SV-IV Peptide 1-16 (i.e. a peptide derived by seminal protein vescicle number IV, SV-IV) to assess its capacity to inhibit the procoagulant activity of normal clotting factor V or Factor V Leiden (FVL). We found that SV-IV protein has potent anti-inflammatory and immunomodulatory properties and also exerts procoagulant activity. In the present work we show that the SV-IV Peptide 1-16, incubated with plasma containing normal Factor V or FVL plasma for 5 minutes reduces the procoagulant capacity of both substances. This is an anticoagulant effect whereas SV-IV protein is a procoagulant. This activity is effective both in terms of the coagulation tests, where coagulation times are increased, and in terms of biochemical tests conducted with purified molecules, where Factor X activation is reduced. Peptide 1-16 was, in the pure molecule system, first incubated for 5 minutes with purified Factor V then it was added to the mix of phosphatidylserine, Ca2+, Factor X and its chromogenic molecule Chromozym X. We observed a more than 50% reduction in lysis of chromogenic molecule Chromozym X by Factor Xa, compared to the sample without Peptide 1-16. Such reduction in Chromozym X lysis, is explained with the reduced activation of Factor X by partial inactivation of Factor V by Peptide 1-16. Thus our study demonstrates that Peptide 1-16 reduces the coagulation capacity of Factor V and Factor V Leiden in vitro, and, in turn, causes factor X reduced activation.
天然凝血因子V是一种抗凝剂，但当被凝血酶、因子X或血小板蛋白酶激活时，它就会变成促凝剂。由于这些双重特性，凝血因子V在凝血/抗凝平衡的调节中起着关键作用。凝血因子V莱顿（FVL）紊乱可能导致血栓形成倾向。凝血因子V或凝血因子V莱顿的激活减少是否可以纠正血栓形成倾向尚不清楚。因此，我们测试了SV-IV肽1-16（即一种源自精囊蛋白囊泡IV的肽，SV-IV），以评估其抑制正常凝血因子V或凝血因子V莱顿（FVL）促凝活性的能力。我们发现SV-IV蛋白具有强大的抗炎和免疫调节特性，并且还具有促凝活性。在本研究中，我们表明，与含有正常凝血因子V或FVL血浆的血浆孵育5分钟的SV-IV肽1-16降低了这两种物质的促凝能力。这是一种抗凝作用，而SV-IV蛋白是一种促凝剂。这种活性在凝血时间延长的凝血试验方面以及在用纯化分子进行的生化试验方面都是有效的，在生化试验中因子X的激活减少。在纯分子系统中，肽1-16首先与纯化的凝血因子V孵育5分钟，然后将其添加到磷脂酰丝氨酸、Ca2+、因子X及其显色分子Chromozym X的混合物中。与没有肽1-16的样品相比，我们观察到因子Xa对显色分子Chromozym X的裂解减少了50%以上。Chromozym X裂解的这种减少可以用肽1-16对凝血因子V的部分失活导致因子X的激活减少来解释。因此，我们的研究表明，肽1-16在体外降低了凝血因子V和凝血因子V莱顿的凝血能力，进而导致因子X的激活减少。
