Tannins as Hemostasis Modulators

The hemostasis system is often affected by complications associated with cardiovascular diseases, which results in thromboembolic events. Compounds of plant origin and plant extracts are considered as a promising source of substances that could modulate the functioning of the hemostasis system and thus reduce the risk of thromboembolism. Among them, tannins, which are plant-origin compounds with potential effects in hemostasis, deserve a special mention. This paper describes the hemostasis-modifying ability of three groups of tannins, namely ellagitannins, gallotannins, and procyanidins. The review highlights the desirable as well as undesirable influence of tannins on specific components of hemostasis, namely platelets, coagulation system, fibrinolysis system, and endothelium, and the multidirectional effect of these compounds on the thrombotic process. Studies performed under normal and pathological conditions such as diabetes or hypercoagulation are described, and the pathophysiology-dependent action of tannins is also highlighted. Most of the studies presented in the paper were performed in vitro, and due to the low bioavailability of tannins more studies should be conducted in the future to understand their actual activity in vivo.

Comparative analysis of hemostasis system state indicators in severe COVID-19

Introduction. Clinical experience in managing patients with a new coronavirus infection caused by the SARS-CoV-2 allowed to identify specific hemostasis disorders, and enables to introduce the concept of COVID-associated coagulopathy. The aim of the study was to assess the direction of coagulogram parameter changes, whole blood clotting parameters and characteristics of platelet and plasma hemostasis in patients with severe COVID-19. Materials and methods. The parameters of the hemostasis system were assessed using venous blood of 12 patients with severe COVID-19 and 16 healthy volunteers. The whole blood clotting process was investigated by low-frequency piezothromboelastography. The platelet count and indicators of spontaneous and ADP-induced platelet aggregation were estimated with the help of a laser platelet aggregation analyzer. Fibrinolytic activity of plasma, plasminogen activity, content of fibrinogen, D-dimer, PTT, APTT, PTI and INR were assessed. Results. An increased level of fibrinogen, a 6-fold increased D-dimer level, and increased PTT were found in patients with severe COVID-19. The patient platelets count was reduced by 51 % (p <0.05), spontaneous platelet aggregation remained at nearly normal level. Almost complete inhibition of ADP-induced platelet reactivity and inhibition of XIIa-dependent fibrinolysis was revealed, despite an increased by 19.3 % (p <0.05) plasminogen activity. Parameters of the whole blood coagulation process pointed a pronounced activation of platelet hemostasis, a significant intensification of the polymerization stage of clot formation and an increased intensity of clot lysis and retraction. Conclusion. The significant increase of D-dimer level and paradoxical inhibition of plasma fibrinolytic activity revealed by test of XIIa-dependent fibrinolysis (in contrast to the increased intensity of clot lysis when assessing the coagulation of whole blood) indicate the complex pathogenic mechanisms of coagulopathy caused by SARS-CoV-2 infection, and the involvement of blood cells and the vascular wall in the process of pathological thrombus formation.

Features of the hemostasis system in patients with non-alcoholic fatty liver disease

Background. Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. In recent years, disorders in the hemostasis system, their role in the progression of liver diseases and the development of cardiovascular complications in NAFLD have been actively studied. The purpose was to investigate the features of the hemostasis system in patients with non-alcoholic fatty liver disease. Materials and methods. We examined 36 individuals with NAFLD (20 women and 16 men) aged 29–73 years. All patients underwent an anthropometric, general clinical, biochemical study of blood serum with the determination of platelets, prothrombin time ratio, international normalized ratio, fibrinogen, ultrasound examination of the abdominal cavity organs with elastometry, followed by statistical data processing. Results. Among patients with NAFLD, class 2 obesity and overweight (30.6 % each), class 1 obesity (27.8 %) prevailed. At the same time, according to the controlled attenuation parameter, 38.9 % of people had a severe degree of steatosis, 33.3 % — moderate and 27.8 % — mild. Regarding the indicators of hemostasis, a significant increase in the level of fibrinogen up to (4.9 ± 0.5) g/l was detected in 44.4 % of patients, its severity tended to grow with an increase in the degree of hepatic steatosis. Conclusions. In 44.4 % of NAFLD patients, with an increase in the degree of hepatic steatosis, the tendency to hypercoagulability has grown with an increase in fibrinogen content by 1.6 times (p < 0.001). Changes in the international normalized ratio, prothrombin time ratio and platelets were determined in isolated cases: more than 83.3 % of patients with NAFLD didn’t have violations of these parameters.

Molecular mechanisms of hemostasis impairment in oncology

Malignant neoplasms are characterized by the presence of the hemostasis system pathology, predisposing cancer patients to thrombohemorrhagic complications. The pathogenesis of cancer-associated coagulopathy is complex and involves a variety of mechanisms. Tumor cells have the ability to activate the host’s hemostasis system, and this phenomenon is controlled by the same oncogenes that are responsible for neoplastic transformation. In addition to predisposing factors to impaired hemostasis from the side of the disease, the anticancer drugs themselves carry risks of developing coagulation disorders. The pathophysiological basis of this kind of disorders caused by chemotherapy is associated with damage to the endothelium, imbalance of coagulation and anticoagulant proteins, platelet dysfunction and their deficiency. In this article, the authors set themselves the goal of generalizing and updating the current knowledge of the molecular mechanisms that cause thrombohemorrhagic risk in cancer.

The role of disorders in the functional activity of platelets in the pathogenesis of microcirculatory disorders in patients with catarrhal gingivitis

A comprehensive examination of patients with chronic catarrhal gingivitis and with exacerbation of chronic catarrhal gingivitis with the inclusion of indicators of the microcirculatory link of the hemostasis system was carried out. In patients with exacerbation of chronic catarrhal gingivitis, platelet aggregation activity is increased compared to that in healthy individuals. This is accompanied by a statistically significant increase in the maximum degree of aggregation, a change in the time to reach the maximum degree of platelet aggregation Key words: platelet aggregation, catarrhal gingivitis, exacerbation of chronic catarrhal gingivitis.

THE USE OF THROMBODYNAMICS TEST IN DIAGNOSTICS OF HEMOSTASIS DISORDERS IN PATIENTS WITH COVID-19 OF VARYING SEVERITY

Background: At the moment, an urgent and unresolved problem is the search for a diagnostic method for disorders of the hemostasis system in patients against the background of the course of a new coronavirus infection. Presumably, integral tests, in particular, the thrombodynamics test, will make it possible to monitor changes in blood clotting, predict the course of the disease in patients with COVID-19. Aims: to comparative assessment of plasma hemostasis parameters and thrombodynamics test in patients with COVID-19 viral infection of varying severity. Methods: The study included 96 patients with a confirmed diagnosis of COVID-19, hospitalized in an infectious diseases hospital on the basis of National Medical Research Center for Obstetrics, Gynecology and Perinatology named after V.I. Kulakov in the period from 04.23.2020 to 06.20.2020 and discharged at the end of treatment. SARS-CoV-2 was identified by PCR. Patients were stratified by severity into 3 groups: mild course (n = 25), moderate course (n = 54), severe course (n = 17). Diagnostics and treatment of patients was carried out in accordance with the Temporary Methodological Recommendations of the Ministry of Health of the Russian Federation for the prevention, diagnosis and treatment of new coronavirus infection, versions 5, 6, 7. In the dynamics of treatment, patients were assessed APTT, prothrombin %, prothrombin time and thrombin time, fibrinogen, D-dimer, platelet count and thrombodynamic test (V / Vi / Vst, Tlag, Cs, D). Results: It was found that significant differences before admission and a week after the start of hospital treatment were observed for the thrombin time, D-dimer, platelet count, and thrombodynamic parameters: V / Vst, Cs, D. PT, APTT, TD (Tlag, D)) with the duration of hospital stay. There was a positive relationship between the content of fibrinogen and D (r = 0.6307, p 0.0001) and a strong positive relationship between PT and Tlag (r = 0.7499, p 0.0001). Conclusions: The thrombodynamics test can be recommended as a potential tool for a personalized approach to monitoring the hemostasis system and treating patients with COVID-19.

The effect of hyperoxia on the hemostasiological status of severely burned patients

The state of the hemostasis system was studied in 9 patients of the middle age group (44 ± 9.94 years) who received thermal trauma on an area of more than 32% (49.4 ± 18.3) of the body surface, accompanied by the development of burn shock. The standard therapy for burn injury was supplemented with HBO sessions. Treatment with hyperbaric oxygen was carried out in pressure chambers BLKS-307, BLKS-307/1. The state of the coagulation, anticoagulant and fibrinolytic links of the hemostasis system, as well as the viscoelastic properties of the blood, were assessed immediately before the HBO session and immediately after it. The total number of comparison pairs was 45. Under the influence of HBO therapy, there was an increase in the activity of antithrombin III (ATIII), protein C (PrS) and a decrease in the viscoelastic properties of blood (p <0.05). Positive deviations in the values of ATIII, Pr C, von Willebrand factor, APTT, prothrombin and thrombin time, fibrinogen, factor XIII, XIIa-dependent fibrinolysis, D-dimers and thromboelastography parameters were revealed. The maximum frequency of their occurrence was recorded for ATIII (95%), the minimum - for the D-dimer (62%). After HBO procedures, undesirable deviations of the hemostatic system parameters were also noted. They were chaotic, were compensated by an increase in the activity of physiological anticoagulants and were not accompanied by complications of a thrombogenic nature. Thus, conducting HBO therapy sessions in the acute period of burn disease increases the activity of physiological anticoagulants and stabilizes the viscoelastic properties of blood. There is a high frequency of occurrence of positive effects of hyperoxia on the components of the hemostasis system. The identification of its undesirable effects indicates the need to monitor the state of the hemostasis system during HBO procedures.

Hemostasis system in elderly patients with ischemic insult in the system of carotid arteries

There was performed investigation of rhelogic properties, of coagulation and anticoagulation blood systems in 88 patients of senile age with ischemic insult in the carotid system. It was determined that for elderly patients highly expressed tendencies for hyperaggregation and suppression of their own fibrinolytic blood activity are characteristic features. Initially increased level of aggregation and hypercoagulation, combined with presence in blood fibrin-monomer complexes were accompanied by progressing DIC syndrome, and as a rule, were associated with steady neurology deficiency and high incidence of mortality. Possible correction ways were considered for hemostasis system disorders in elderly patients.