Numerous studies have shown that the polyphenolics have antithrombotic properties,
namely to aid fibrinolysis process and reducing platelet aggregation [1]. Moreover,
the polyphenol-rich plant material is tormentil (Potentilla erecta) used for a long time in traditional medicine [2]. For the first time, we showed
antithrombotic effect of tormentil extract in adult healthy male Wistar rat. We have
used model of electrically-induced arterial thrombosis in carotid artery in rat and
estimated collagen-stimulated platelet aggregation ex vivo in a whole blood of thrombotic rats with the electronic aggregometer: a novel device
for assessing platelet behavior [3]. The extract was administered per os, twice daily
for 10 days in doses of 100, 200 or 400 mg/kg each in volume of 2 mL/kg in 5% water
solution of gummi arabici (VEH). In the extract ellagitannins (agrimoniin) and oligomeric
proanthocyanidins were detected by using LC-TOF-MS method as the dominating compounds.
The prothrombin time, activated partial thromboplastin time, QUICK index and Fibrinogen
level, as well as tissue plasminogen activator and plasminogen activator inhibitor
(PAI-1) levels and blood cells count were also determined. We have also measured blood
pressure directly in left common artery in rat [4]. All the experiments were approved
by the Local Ethics Commetee. We have demonstrated, that tormentil extract in a highest
dose of 400 mg/kg decreases arterial thrombus weight (0.65 ± 0.06 mg vs VEH 0.95 ± 0.07 mg; p< 0.05, n = 9 – 11), inhibits platelet aggregation (9.59 ± 0.08 Ohms vs VEH 12.11 ± 0.69 Ohms, p< 0.05, n = 9 – 11) and decreases PAI-1 total antigen level (0.71 ± 0.10 ng/mL vs VEH 1.31 ± 0.15 ng/mL, p< 0.05, n = 4 – 5). There were no correlations between platelet count nor aggregation
and PAI-1 level. We also observed silght, not statistically important hypotensive
effect of the highest does of the extract. To conclude, the extract inhibits arterial
thrombosis without disturbing coagluations system nor blood cell count. The mechanism
of beneficial antithrombotic effect seems to depend on platelet inhibition and activation
of fibrinolysis. Further studies concerning detailed mechanism of action as well as
haemodynamic effect are needed.
Acknowledgements: The study was conducted with the use of equipment purchased by Medical
University of Bialystok as part of the OP DEP 2007 – 2013, Priority Axis I.3, contract
No. POPW.01.03.00 – 20 – 001/12 and financially supported by the Medical University
of Bialystok, Poland (Project No. N/ST/ZB/15/001/2212).
Keywords: Potentilla erecta, thrombosis, platelet, fibrinolysis.
References:
[1] Quiñonesa M, Miguelb M, Aleixandrea A. Beneficial effects of polyphenols on cardiovascular disease. Pharmacol Res 2013,
68: 125 – 131
[2] Tomczyk M, Latté KP. Potentilla – a review of its phytochemical and pharmacological profile. J Ethnopharmacol 2009,
122: 184 – 204
[3] Cardinal DC, Flower RJ. The electronic aggregometer: a novel device for assessing platelet behavior in blood.
J Pharmacol Methods 1980, 3: 135 – 158
[4] Kramkowski K, Leszczynska A, Mogielnicki A, Chlopicki S, Fedorowicz A, Grochal E,
Mann B, Brzoska T, Urano T, Motterlini R, Buczko W. Antithrombotic properties of water-soluble carbon monoxide-releasing molecules. Arterioscler
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