Soluble tissue factor emerges from inflammation

Cardiovascular disease and thrombosis: Intersections with the immune system, inflammation, and the coagulation system

The coagulation and immune system, both essential physiological systems in the human body, are intricately interconnected and play a critical role in determining the overall health of patients. These systems collaborate via various shared regulatory pathways, such as the Tissue Factor (TF) Pathway. Immunological cells that express TF and generate pro-inflammatory cytokines have the ability to affect coagulation. Conversely, coagulation factors and processes have a reciprocal effect on immunological responses by stimulating immune cells and regulating their functions. These interconnected pathways play a role in both preserving well-being and contributing to a range of pathological disorders. The close relationship between blood clotting and inflammation in the development of vascular disease has become a central focus of clinical study. This research specifically examines the crucial elements of this interaction within the contexts of cardiovascular disease and acute coronary syndrome. Tissue factor, the primary trigger of the extrinsic coagulation pathway, has a crucial function by inducing a proinflammatory reaction through the activation of coagulation factors. This, in turn, initiates coagulation and subsequent cellular signalling pathways. Protease-activated receptors establish the molecular connection between coagulation and inflammation by interacting with activated clotting factors II, X, and VII. Thrombosis, a condition characterised by the formation of blood clots, is the most dreaded consequence of cardiovascular disorders and a leading cause of death globally. Consequently, it poses a significant challenge to healthcare systems. Antithrombotic treatments efficiently target platelets and the coagulation cascade, but they come with the inherent danger of causing bleeding. Furthermore, antithrombotics are unable to fully eliminate thrombotic events, highlighting a treatment deficiency caused by a third mechanism that has not yet been sufficiently addressed, namely inflammation. Understanding these connections may aid in the development of novel approaches to mitigate the harmful mutual exacerbation of inflammation and coagulation. Gaining a comprehensive understanding of the intricate interaction among these systems is crucial for the management of diseases and the creation of efficacious remedies. Through the examination of these prevalent regulatory systems, we can discover novel therapeutic approaches that specifically target these complex illnesses. This paper provides a thorough examination of the reciprocal relationship between the coagulation and immune systems, emphasising its importance in maintaining health and understanding disease processes. This review examines the interplay between inflammation and thrombosis and its role in the development of thrombotic disorders.

Inflammation and coagulation abnormalities via the activation of the HMGB1‑RAGE/NF‑κB and F2/Rho pathways in lung injury induced by acute hypoxia

High‑altitude acute hypoxia is commonly associated with respiratory cardiovascular diseases. The inability to adapt to acute hypoxia may lead to cardiovascular dysfunction, lung injury and even death. Therefore, understanding the molecular basis of the adaptation to high‑altitude acute hypoxia may reveal novel therapeutic approaches with which to counteract the detrimental consequences of hypoxia. In the present study, a high‑altitude environment was simulated in a rat model in order to investigate the role of the high mobility group protein‑1 (HMGB1)/receptor for advanced glycation end products (RAGE)/NF‑κB and F2/Rho signaling pathways in lung injury induced by acute hypoxia. It was found that acute hypoxia caused inflammation through the HMGB1/RAGE/NF‑κB pathway and coagulation dysfunction through the F2/Rho pathway, both of which may be key processes in acute hypoxia‑induced lung injury. The present study provides new insight into the molecular basis of lung injury induced by acute hypoxia. The simultaneous activation of the HMGB1/RAGE/NF‑κB and F2/Rho signaling pathways plays a critical role in hypoxia‑induced inflammatory responses and coagulation abnormalities, and provides a theoretical basis for the development of potential therapeutic strategies.

Elevated levels of procoagulant microvesicles in patients with dengue fever

Background: The levels of procoagulant microvesicles (MVs) and tissue factor (TF)-bearing MVs may be increased in many conditions, including dengue fever (DF). This study aimed to measure the levels of MVs and TF-bearing MVs in patients with DF and matched healthy controls. Materials & methods: Levels of MVs and TF-bearing MVs in the plasma of patients with DF and matched healthy controls were measured using functional assay. Results: The patient group had significantly elevated levels of MVs (p < 0.001) and slightly increased levels of TF-bearing MVs (p = 0.454) compared with the matched healthy controls. Conclusion: Elevated levels of MVs and TF-bearing MVs could be used as biomarkers to evaluate the hemostatic function of patients with DF.

The Bidirectional Interactions Between Inflammation and Coagulation in Fracture Hematoma

IMPACT STATEMENT

The review leads to better understanding of the interrelation between inflammation mediators and coagulation factors in the early fracture hematoma, and their influences on hematoma formation in the beginning of fracture healing. Furthermore, development of therapies aimed at simultaneous modulation of both coagulation factors and inflammation factors that affect hematoma structure, rather than specific factors, may be most promising.

Platelet hyperactivity and fibrin clot structure in transient ischemic attack individuals in the presence of metabolic syndrome: a microscopy and thromboelastography study

BACKGROUND

Strokes are commonly preceded by transient ischemic attacks (TIAs). TIA is often associated with metabolic syndrome (causing chronic inflammation), resulting in a proinflammatory- and procoagulant-environment. The aim of this study was to determine whether platelet- and fibrin network-morphology or coagulation profiles of individuals that suffered a TIA in the presence of metabolic syndrome was altered when compared to healthy individuals.

MATERIALS AND METHODS

The study consisted of 40 voluntary participants. Twenty individuals that suffered a TIA in the previous 48 h with at least two metabolic syndrome risk factors present and twenty healthy age-matched controls. Scanning electron- and atomic force microscopy was used to study platelet- and fibrin-morphology, atomic force microscopy was used to study platelet- and fibrin fiber-elasticity and thromboelastography for the study of coagulation profiles. Statistical analysis was performed to compare the two groups. In all cases a p-value of less than 0.05 was considered statistically significant.

RESULTS

Platelets of the control group appeared spherical with few pseudopodia present while the platelets of the TIA individuals presented with numerous pseudopodia and spreading, indicating activation. Platelet aggregation was also present. The fibrin networks of the healthy individuals consist of thick and thin fibers that form an organized network of fibers. The fibrin networks of the TIA individuals appeared less organized with less taut fibers. Fibrin fiber thickness was found to be significantly increased in the TIA group (p-value <0.001) when compared to healthy controls. The thicker fibers formed irregular networks with thick masses of fibrin fibers. Platelet and fibrin fiber elasticity was found to be significantly lower in the experimental group (p-value 0.0042 and p-value 0.0007 respectively). The hemostatic profiles of the diseased individuals did not differ significantly (p-value > 0.05) from the healthy controls, indicating a normal functioning coagulation cascade.

CONCLUSION

The findings indicate that pathological clot formation is not caused by alterations in the coagulation cascade but rather by the premature activation of platelets (as a result of chronic inflammation) that in turn causes altered fibrin formation.

The Interface between Inflammation and Coagulation in Cardiovascular Disease

The intimate connection between coagulation and inflammation in the pathogenesis of vascular disease has moved more and more into focus of clinical research. This paper focuses on the essential components of this interplay in the settings of cardiovascular disease and acute coronary syndrome. Tissue factor, the main initiator of the extrinsic coagulation pathway, plays a central role via causing a proinflammatory response through activation of coagulation factors and thereby initiating coagulation and downstream cellular signalling pathways. Regarding activated clotting factors II, X, and VII, protease-activated receptors provide the molecular link between coagulation and inflammation. Hereby, PAR-1 displays deleterious as well as beneficial properties. Unravelling these interrelations may help developing new strategies to ameliorate the detrimental reciprocal aggravation of inflammation and coagulation.