Fibrinolytic and Thrombolytic Effects of an Enzyme Purified from the Fruiting Bodies of Boletus pseudocalopus (Agaricomycetes) from Korea.

A fibrinolytic enzyme with thrombolytic, anticoagulant activities was purified from fruiting bodies of wild-growing mushroom Boletus pseudocalopus Hongo and homogenized with a two-step procedure with a 6.11-fold increase in specific activity and 3.2% recovery. The molecular weight of the enzyme was estimated to be 63.5 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The enzyme was active at 40°C and pH 7, and activity was inhibited by zinc metal ion and by serine protease and trypsin inhibitors phenylmethylsulfonyl fluoride and N-α-tosyl-l-lysinyl-chloromethylketone. The enzyme displayed high specificity for Pyro-Glu-Gly-Arg-pNA. In vitro assays showed that the enzyme was able to degrade fibrin and blood clots, inhibit thrombin and activated factor X, and alter the density or structural change of fibrin clots. It could also delay activated partial thromboplastin time and prothrombin time. These results suggest that the enzyme may have characteristics of a trypsin or serine-like enzyme with fibrinolytic and thrombolytic activities and may have potential as an antithrombotic agent for blood clotting disorders.

Investigation of Potential Antioxidant, Thrombolytic and Neuropharmacological Activities of Homalomena aromatica Leaves Using Experimental and In Silico Approaches.

The leaves of Homalomena aromatica are traditionally used in Bangladesh for the treatment of different chronic ailments. The purpose of this study was to explore in vitro antioxidant, thrombolytic activities, and in vivo neuropharmacological effects of methanolic extract of Homalomena aromatica (MEHA) leaves. Antioxidant activity of MEHA was assessed by a DPPH free radical scavenging assay and total phenolics content, total flavonoids content were also measured. The thrombolytic activity was determined by percentage of clot lysis and neuropharmacological activities by hole board, tail suspension, forced swimming and elevated plus maze tests. The results showed that the IC50 value of the extract against DPPH was 199.51 µg/mL. Quantitative analysis displayed higher contents of phenolics and flavonoids (147.71 mg gallic acid equivalent/g & 66.65 mg quercetin equivalent/g dried extract, respectively). The extract also showed a significant clot lysis (33.31%) activity. In case of anxiolytic activity, the elevate plus maze (EPM) test demonstrated an increase in time spent in open arms, and in case of hole board test, the number of head dipping was also significantly increased (p < 0.05). All the test compared with control (1% Tween in water) and standard (diazepam 1 mg/kg), significant dose (200 & 400 mg/kg) dependent anxiolytic activity was found. In antidepressant activity, there was a significant decrease in period of immobility in both test models (tail suspension and forced swimming) (p < 0.05). Moreover, 13 compounds were identified as bioactive, showed good binding affinities to xanthine oxidoreductase, tissue plasminogen activator receptor, potassium channel receptor, human serotonin receptor targets in molecular docking experiments. Furthermore, ADME/T analysis revealed their drug-likeness, likely pharmacological actions and non-toxic upon consumption. Taken together, our finding support the traditional medicinal use of this plant, which may provide a potential source for future drug discovery.

Role of Whole Plant Extract of Nelumbo nucifera Gaertn in the Treatment of Thrombolysis.

AIM: This study aims to find out the components responsible for the antithrombotic activity of Nelumbo nucifera. MATERIAL AND METHODS: Petroleum ether, chloroform and hydroalcoholic extracts of whole plant of Nelumbo nucifera (Lotus) were prepared and assessed for its thrombolytic, anti-platelet aggregation activity and bleeding time. The extracts were further analyzed through HPTLC and GC-MS. Statistical analysis was conducted through ANOVA trailed by Tukey's multiple comparison test test. RESULTS: Hydroalcoholic extract showed the highest activity at the concentration of 400µg/ml in thrombolytic assay (42.03 ± 5.76), anti-platelet aggregation assay (57.93 ± 1.68) and bleeding time (70.17 ± 2.16) in comparison to clopodigrel (33.76 ± 3.43), aspirin (66.55 ± 1.86) and aspirin (93.85 ± 2.75) at the concentration of 100 µg/ml respectively. 25 peaks were identified through GC-MS, out of which, ferulic acid (14.2µ/g) and quercetin (5.4 µ/g) are active chemical compounds. HPTLC showed different chromatograms in hydroalcoholic extracts like (1) chlorogenic, (2) quercetin, (3) benzoic acid, (4) caffeic acid, (5) ferulic acid, (6) kaempferol, and (7) gallic acid. CONCLUSION: Based on these findings, flavonoids present in hydroalcoholic extract may be developed into a drug for clinical application for the treatment of thrombosis in patients.

Clinical outcomes and plasma clot permeability and lysability in patients with venous thromboembolism on rivaroxaban: a cohort study.

INTRODUCTION: Denser fibrin structure and impaired fibrinolysis reported in patients following venous thromboembolism (VTE) can predict recurrent VTE after cessation of anticoagulation. OBJECTIVES: The aim of the study was to investigate whether the properties of fibrin clot may be useful in predicting adverse events in patients with VTE receiving rivaroxaban. PATIENTS AND METHODS: In 132 patients with VTE treated with rivaroxaban for 8 weeks or longer, we determined plasma clot permeability (Ks) and clot lysis time (CLT) in blood samples collected 2 to 28 hours after rivaroxaban intake (20 mg/d). The primary endpoint was a composite of major and clinically relevant nonmajor bleeding, while the secondary endpoint was recurrent symptomatic VTE. RESULTS: During a median follow­ up of 32 months, the annual rates of primary and secondary endpoints were 3.6% and 2.7%, respectively. There were no differences in Ks and CLT between individuals who experienced the primary endpoint and the remainder. Patients with recurrent VTE had lower baseline Ks (-26.7%) and prolonged CLT (+20.8%) on rivaroxaban, without differences in rivaroxaban concentrations at the time of blood collection. After adjustment for confounding factors, Ks was the only predictor of VTE recurrence on rivaroxaban (odds ratio, 0.23; 95% CI, 0.06-0.94). CONCLUSIONS: Our study suggests that Ks assessed on rivaroxaban may provide prognostic information about the risk of recurrent VTE in anticoagulated patients.

A comparative study of the antioxidant, antimicrobial, cytotoxic and thrombolytic potential of the fruits and leaves of Spondias dulcis.

OBJECTIVE: To investigate the antioxidant, antimicrobial, cytotoxic and thrombolytic property of the fruits and leaves of Spondias dulcis (S. dulcis). METHODS: Methanolic extracts of fruits and leaves of S. dulcis were partitioned with chloroform and dichloromethane. The antioxidant potential of the crude extract and partitioned fractions were evaluated in terms of total phenolic content, total flavonoid content, DPPH radical scavenging potential, reducing potential and total antioxidant capacity by specific standard procedures. The antimicrobial activity was evaluated using disc diffusion method. The cytotoxicity was evaluated by using brine shrimp lethality bioassay and compared with vincristine sulfate. The thrombolytic activity was compared with streptokinase. RESULTS: The methanolic fruit extract exhibited the highest phenolic content, flavonoid content and antioxidant capacity, among the other extracts, with the highest DPPH radical scavenging activity at a concentration of 10 µg/mL (IC50: 1.91 µg/mL) and maximum reducing power at a concentration of 100 µg/mL (EC50: 3.58 µg/mL). Though all extract showed moderate antimicrobial activity against the bacterial strains, weak or no activity against fungus. The range of LC50 value of all extracts was 1.335-14.057 µg/mL which was far lower than the cut off index for cytotoxicity. All extracts exhibited statistically significant (P<0.001) thrombolytic activity. CONCLUSIONS: Our study suggested that S. dulcis exhibits antimicrobial activities against a wide variety of strains while it possesses significant antioxidant, cytotoxic and thrombolytic activity.