Effect of Peptides from Plasma of Patients with Coronary Artery Disease on the Vascular Endothelial Cells

Coagulation Parameters in Post-Covid-19 Condition in Relation to Various Titers of Anti-SARS-CoV-2 IgG in Blood Plasma

Background and Objectives

Post-COVID-19 condition is thought to affect 10-20% of people at least 3 months after a diagnosis of COVID-19 and two months of symptoms. Post-COVID-19 condition presents itself with many clinical effects with varying degrees of severity ranging from a mild cough to a life-threatening coagulopathy. Our study aimed to identify a relationship between the titers of anti-SARS-CoV-2 IgG and anticoagulation parameters: antithrombin III (ATIII), protein C (PC) and thrombomodulin (TM).

Materials and Methods

Blood plasma was collected from healthy donors aged 25-45 who had recovered from COVID-19 3-6 months ago and their titers of anti-SARS-CoV-2 IgG and ATIII, PC, and TM were measured.

Results

We found that concentrations and activities of key anticoagulation parameters (ATIII, PC, and TM) measured in donor plasma during the post-COVID-19 varied in relation to the titers of anti-SARS-CoV-2 IgG.

Conclusion

While we identified a dysfunction of anticoagulation parameters in patients with post-COVID-19, we aim to explore the subpopulation antibody IgG fraction directly using in vivo and in vitro experiments with the possibility to contribute to the development of treatment options for post-COVID-19 conditions.

Evaluation of proteolytic activity and serine proteases distribution in plasma from patients with bladder cancer

Background

Bladder cancer (BC) is an aggressive disease with a poor prognosis. A bladder tumor, like other malignant neoplasms, is characterized by the presence of both cancer cells and stromal cells which secrete cytokines, chemokines, growth factors, and proteolytic enzymes. One such class of proteolytic enzymes are serine proteases, which take part in the tumor microenvironment formation via supporting and contributing to tumor progression. This study aims to evaluate the proteolytic activity and serine protease contribution in plasma from BC patients.

Methods

The research involved patients of Alexandrovsky city clinical hospital aged 52-76 with transitional cell carcinoma of the bladder. All examined patients were divided into five groups: the control group included conditionally healthy donors, while other patients were grouped according to their tumor stage (I, II, III and IV). Plasma plasminogen levels were determined by enzyme-linked immunosorbent assay, and the potential activity was measured by chromogenic plasminogen assay. Serine proteases fractions were obtained by the affinity chromatography method, and enzyme concentration in the selected fractions were determined by the Bradford method. Serine proteases distribution was investigated by electrophoresis in a polyacrylamide gel.

Results

It was determined that the concentration, potential activity of plasminogen, and the total amount of serine proteases in plasma from BC patients were greater than the values of the corresponding indicators in healthy donors. This could be one of the factors contributing to increased proteolysis seen in the process of carcinogenesis. Plasminogen concentration in BC patients with stage IV disease; however, displayed a tendency to be reduced compared to earlier stages, and the potential activity of plasminogen was significantly lower in patients with stages III - IV BC. Futhermore, a tumor stage specific gradual decline in the serine protease plasma content was shown. The results of electrophoretic analysis established a significant diminishment in the percentage of high molecular weight components (under non-reducing conditions) and their complete disappearance (under reducing conditions) in plasma serine protease fractions from BC patients. A decline in the percentage of heavy and light plasmin chains in BC patients was also observed. Additionally, a rise in the degraded forms of plasminogen/plasmin content was seen in BC samples, as well as the presence of fractions corresponding to trypsin and NE (under non-reducing conditions) that were absent in the control samples.

Conclusion

The results indicate significant changes in the proteolytic activity of plasma, from BC patients when compared to healthy controls, which is accompanied by alterations in serine protease distribution caused by tumor microenvironment pecularlities at the different stages of oncopathology.

Endothelin-1 in Health and Disease

Discovered almost 40 years ago, the potent vasoconstrictor peptide endothelin-1 (ET-1) has a wide range of roles both physiologically and pathologically. In recent years, there has been a focus on the contribution of ET-1 to disease. This has led to the development of various ET receptor antagonists, some of which are approved for the treatment of pulmonary arterial hypertension, while clinical trials for other diseases have been numerous yet, for the most part, unsuccessful. However, given the vast physiological impact of ET-1, it is both surprising and disappointing that therapeutics targeting the ET-1 pathway remain limited. Strategies aimed at the pathways influencing the synthesis and release of ET-1 could provide new therapeutic avenues, yet research using cultured cells in vitro has had little follow up in intact ex vivo and in vivo preparations. This article summarises what is currently known about the synthesis, storage and release of ET-1 as well as the role of ET-1 in several diseases including cardiovascular diseases, COVID-19 and chronic pain. Unravelling the ET-1 pathway and identifying therapeutic targets has the potential to treat many diseases whether through disease prevention, slowing disease progression or reversing pathology.