Streptokinase: An Efficient Enzyme in Cardiac Medicine

Recent advances in microfluidic technology of arterial thrombosis investigations

Microfluidic technology has emerged as a powerful tool in studying arterial thrombosis, allowing researchers to construct artificial blood vessels and replicate the hemodynamics of blood flow. This technology has led to significant advancements in understanding thrombosis and platelet adhesion and aggregation. Microfluidic models have various types and functions, and by studying the fabrication methods and working principles of microfluidic chips, applicable methods can be selected according to specific needs. The rapid development of microfluidic integrated system and modular microfluidic system makes arterial thrombosis research more diversified and automated, but its standardization still needs to be solved urgently. One key advantage of microfluidic technology is the ability to precisely control fluid flow in microchannels and to analyze platelet behavior under different shear forces and flow rates. This allows researchers to study the physiological and pathological processes of blood flow, shedding light on the underlying mechanisms of arterial thrombosis. In conclusion, microfluidic technology has revolutionized the study of arterial thrombosis by enabling the construction of artificial blood vessels and accurately reproducing hemodynamics. In the future, microfluidics will place greater emphasis on versatility and automation, holding great promise for advancing antithrombotic therapeutic and prophylactic measures.

Maggot Kinase and Natural Thrombolytic Proteins

Thrombolytic enzymes constitute a class of proteases with antithrombotic functions. Derived from natural products and abundant in nature, certain thrombolytic enzymes, such as urokinase, earthworm kinase, and streptokinase, have been widely used in the clinical treatment of vascular embolic diseases. Fly maggots, characterized by their easy growth and low cost, are a traditional Chinese medicine recorded in the Compendium of Materia Medica. These maggots can also be used as raw material for the extraction and preparation of thrombolytic enzymes (maggot kinase). In this review, we assembled global research reports on natural thrombolytic enzymes through a literature search and reviewed the functions and structures of natural thrombolytic enzymes to provide a reference for natural thrombophilic drug screening and development.

Targeted drug delivery to the thrombus by fusing streptokinase with a fibrin-binding peptide (CREKA): an in silico study

Aim: Streptokinase has poor selectivity and provokes the immune response. In this study, we used in silico studies to design a fusion protein to achieve targeted delivery to the thrombus. Materials & methods: Streptokinase was analyzed computationally for mapping. The fusion protein modeling and quality assessment were carried out on several servers. The enzymatic activity and the stability of the fusion protein and its complex with plasminogen were assessed through molecular docking analysis and molecular dynamics simulation respectively. Results: Physicochemical properties analysis, protein quality assessments, protein-protein docking and molecular dynamics simulations predicted that the designed fusion protein is functionally active. Conclusion: Our results showed that this fusion protein might be a prospective candidate as a novel thrombolytic agent with better selectivity.

Evaluation of clinical efficacy of streptokinase by comparison with the thrombolytic agent on animal model

Cardiovascular disorders, including acute myocardial infarction (AMI), often lead to blood clot formation, impacting blood circulation. Streptokinase, a cost-effective and widely available thrombolytic agent, is crucial in treating thrombosis. This study aimed to produce streptokinase from Streptococcus pyogenes EBL-48 and compare its efficacy with heparin in an animal model. We evaluated the clot-lysing effectiveness of streptokinase produced from Streptococcus pyogenes EBL-48, emphasizing its low cost and ease of production. Streptokinase was produced using pre-optimized fermentation media and purified through ion exchange and gel-filtration chromatography. In vivo analysis involved inducing clots in a trial animal model using ferric chloride, comparing streptokinase with heparin. Ultrasonography assessed the clot-lysing activity of streptokinase. Streptokinase (47 kDa) effectively lysed clots, proving its low cost, easy production, and minimal adverse effects. Ultrasonography confirmed its fibrinolytic efficacy. These findings highlight potential as an affordable and easily produced thrombolytic agent, particularly relevant in resource-limited settings. Streptokinase efficacy and minimal adverse effects make it a promising option for thrombolytic therapy, especially in economically constrained regions. Future studies could optimize production techniques, explore different strains, and conduct clinical trials for human validation. Comparative studies with other thrombolytic agents would enhance understanding of their advantages and limitations.

Effectiveness of Combined Thrombolysis and Mild Hypothermia Therapy in Acute Cerebral Infarction: A Meta-Analysis

Objective

To evaluate the effectiveness and safety of thrombolytic therapy combined with mild hypothermia in patients with acute cerebral infarction (ACI), based on a meta-analysis of randomized controlled trials (RCTs).

Methods

PubMed, EMBASE, Cochrane Library, and Chinese National Knowledge Infrastructure Database of Controlled Trials were systematically screened for randomized controlled trials (RCTs) of thrombolytic therapy combined with mild hypothermia in treating ACI from inception to January 2021. Participation and outcomes among intervention enrollees are as follows: P, participants (patients in ACI); I, interventions (thrombolysis in combination with mild hypothermia therapy); C, controls (thrombolysis merely); O, outcomes (main outcomes are the change of NIHSS, glutathione peroxidase, superoxide dismutase, malondialdehyde, inflammatory factor interleukin-1β, tumor necrosis factor-α, and adverse reaction). Following data extraction and quality assessment, a meta-analysis was performed using RevMan 5.3 software.

Results

A total of 26 RCTs involving 2071 patients were included. Compared to thrombolysis alone, thrombolytic therapy combined with mild hypothermia leads to better therapeutic efficacy [RR = 1.23, 95% CI (1.16, 1.31)], NIHSS [MD = -2.02, 95% CI (-2.55, -1.49)], glutathione peroxidase [MD = 8.71, 95% CI (5.55, 11.87)], superoxide dismutase [MD = 16.52, 95% CI (12.31, 19.74)], malondialdehyde [MD = -1.86, 95% CI (-1.98, -1.75)], interleukin-1β [MD = -3.48, 95% CI (-4.88, -2.08)], tumor necrosis factor-α [MD = -0.46, 95% CI (-3.39, 2.48)], and adverse reaction [RR = 0.87, 95% CI (0.63, 1.20)].

Conclusions

Thrombolytic therapy combined with mild hypothermia demonstrates a beneficial role in reducing brain nerve function impairment and inflammatory reactions in ACI subjects analysed in this meta-analysis.

Polylactide-based stent coatings: biodegradable polymeric coatings capable of maintaining sustained release of the thrombolytic enzyme streptokinase

The paper describes synthesis and testing of novel biodegradable polylactide-based polymer membranes with desired mechanical properties, which are capable of sustained and directed release of biomacromolecules with high molecular weight (in particular, streptokinase; m.w. 47 kDa). Streptokinase is a pharmaceutical agent, possessing a pronounced thrombolytic activity. The membranes synthesized had a percentage elongation of 2–11% and tensile strength of 25–85 MPa. They were biodegradable – yet being stored in aqueous media in the absence of biological objects, would be dissolved by no more than 10% in 6 months. The synthesized membranes were capable of controlled release of streptokinase into the intercellular space, with the enzyme retaining more than 90% of its initial activity. The rate of streptokinase release from the membranes varied from 0.01 to 0.04 mg/day per cm2 of membrane surface. The membrane samples tested in the work did not have any short-term toxic effects on the cells growing de novo on the membrane surface. The mitotic index of those cells was approximately 1.5%, and the number of non-viable cells on the surface of the polymer films did not exceed 3–4% of their total amount. The implantation of the synthesized polymers – as both individual films and coatings of nitinol stents – was not accompanied by any postoperative complications. The subsequent histological examination revealed no abnormalities. Two months after the implantation of polymer films, only traces of polylactide were found in the implant-surrounding tissues. The implantation of stents coated with streptokinase-containing polymers resulted in the formation of a mature and thick connective-tissue capsules. Thus, the polylactide membranes synthesized and tested in this work are biodegradable, possess the necessary mechanical properties and are capable of sustained and directed release of streptokinase macromolecules.