Platelets amino acids spectrum and coagulation in patients with atherosclerosis

Type of funding sources: Public Institution(s). Main funding source(s): O.O.Bogomolets National Medical University

Relevance: Amino acids are one of the important group of myocardial metabolites. Today metabolomic analysis has become an essential tool for understanding the pathophysiology of cardiovascular disorders [1, 3]. Coagulation factors interact with platelets by binding to platelet receptors directly or indirectly or by cleaving of the platelet receptors. Arterial thrombosis as a most life threating atherosclerosis (AS) complication is characterized by significant interplay between platelets and coagulation [2]. Therefore, it is important to find pathogenic links between changes in platelet structure and coagulation data.

78 patients were investigated. All patients were divided into two groups – 20 patients without AS (control group) and 58 patients with AS (mean group). Diagnosis was verified by carotid and peripheral arteries ultrasound. Statistically all groups were compatible by the main clinical features (age, gender, concominant disorders, etc.). For amino acid platelet determination, platelet-rich plasma was obtained after blood centrifugation at 3000 g 15 min of 10 ml of the remaining plasma. One milliliter of platelet-rich plasma was centrifuged at 2,500 g for 15 min to obtain a platelet pellet that was frozen at –20°C until assayed. All the samples were stored for a maximum of 3 mounth.  Platelets amino acid spectrum was checked by ion exchange liquid column gas chromatography.

Patients of the mean group has significantly differences compared with control group: decreasing of taurine (6.54±9.49 vs 5.94±4.36 mkmol/107), threonine (0.48±1.69 vs 0.22±1.24 mkmol/107), glycine (2.10±3.79 vs 1.02±2.11 mkmol/107) and glutamine (2.54±5.70 vs 1.88±2.76 mkmol/107) levels; increasing alanine (1.99±4.03 vs 2.81±3.06 mkmol/107), valine (0.96±1.98 vs 1.63±1.26 mkmol/107) and isoleucine (0.53±1.84 vs 2.91±1.61 mkmol/107) levels. Also in mean group acquired leucine (2.51±0.93 mkmol/107) that was not present in control group. Total amount of branch-chained amino acids (BCAA) in platelets is also increased significantly. Therefore, in mean group patients were significant higher-level activated partial thromboplastin time (APTT) (34.3±2.87 vs 28.8±3.29 s) and lower fibrinogen (205±17 vs 213±2 mg/dl). Direct significant correlation was checked between glycine (r=0,634; p<0,05), alanine (r=0,587; p<0,05) and fibrinogen, also between APTT and platelets BCAA (r=0,724; p<0,01).

We obtained reliable changes in platelets amino acid spectrum and coagulation tests in patients with atherosclerosis. In addition, significant correlations between themes can be related with pathogenic platelets changes. In any case more deeper studies are desirable.