Effects of a novel marine natural product: pyrano indolone alkaloid fibrinolytic compound on thrombolysis and hemorrhagic activities in vitro and in vivo.

Fungi fibrinolytic compound 1 (FGFC1) is a novel marine natural product as a low-weight fibrinolytic pyranoindole molecule, whose thrombolytic effects were evaluated on FITC-fibrin (Fluorescein isothiocyanate, FITC) degradation methods in vitro and on acute pulmonary thromboembolism animal model in vivo. We determined the FGFC1 induced thrombolysis that stems from its fibrin(ogen)olytic activities as measured by fibrin(ogen) degradation products (FDPs) experiment, acute pulmonary thromboembolism animal model experiment, and euglobulin lysis assay. In vitro, measurement of FITC-fibrin degradation revealed that fibrin hydrolysis occurred in a concentration-dependent manner of FGFC1 from 5 to 25 µ mol/L. In vivo test of a classical acute pulmonary thromboembolism model in rat showed that when the injected dose was 5 mg/kg or above, FGFC1 was effective in dissolution of extrinsic FITC-fibrin induced blood clots. Euglobulin lysis time (ELT) in FGFC1-treated rats was shortened 30 s compared with rats in the positive control group, which were injected with clopidogrel sulfate and single-chain urokinase-type plasminogen activator. As compared to the control, FGFC1 (5-25 mg/kg) did not significantly alter the formation of fibrinogen and FDPs in vivo. Our research indicates that FGFC1 presents pharmacodynamic action in both the thrombolysis and the hemolytic procedure, which can be characterized by fibrinogenolysis in blood and FDPs in plasma. In vivo, increasing fibrinolytic doses of FGFC1 from 5 to 25 mg/kg did not induce fibrinogenolysis when compared with control group, this result corresponds to that FGFC1 did not induce the increasing of FDPs (compared with the saline-treated control). It indicates that the FGFC1 may act as a novel thrombolytic agent and represent an effective approach to the treatment of thrombus without significant risk of hemorrhagic activity.

Pharmacokinetics and tissue distribution of a novel marine fibrinolytic compound in Wistar rat following intravenous administrations.

We investigated a novel marine fibrinolytic compound for use in thrombolytic therapy. Pharmacokinetics and the tissue distribution of this novel marine fibrinolytic compound, FGFC1(2) (fungi fibrinolytic compound 1), were investigated in Wistar rats after intravenous (IV) bolus administration of two concentrations (10 and 20mg/kg). Plasma FGFC1 and tissue extracts were measured using HPLC with UV detection. FGFC1 was detected using a C18 column with a gradient eluted mobile phase of acetonitrile-water (0.1% trifluoroacetic acid), 1.0mL/min. Chromatograms were monitored at 265nm (column temperature: 40°C). Pharmacokinetic data indicate that FGFC1 fitted well to a two-compartment model. Elimination half-lives (t1/2) of FGFC1 were 21.51±2.17 and 23.22±2.11min for 10 and 20mg/kg, respectively. AUC0-t were 412.19±19.09, 899.09±35.86µg/mLmin, systemic clearance (CL) was 0.023±0.002, 0.022±0.002 ((mg/kg)/(µg/mL)/min) and the mean residence time (MRT) was 10.15±0.97, 9.65±1.40min at 10 and 20mg/kg, respectively. No significant differences were observed in the systemic clearance and mean residence time at the tested doses, suggesting linear pharmacokinetics in rats. Tissue distribution data reveal that FGFC1 distributed rapidly in most tissues except the brain and that the highest concentration of the drug was in the liver. In the small intestine, FGFC1 initially increased and then declined, but remained comparatively high 60min after administration, suggesting that enterohepatic circulation may exist.

[Response surface methodology to optimize marine microbe culture for producing fungi fibrinolytic compound].

Response surface methodology was applied to optimize the fermentation conditions of FGFC1 (Fungi fibrinolytic compound 1). On the basis of single factor tests, response surface analysis was designed by Design-Expert, and the effects of culture time, ornithine hydrochloride addition and culture temperature on the yield of FGFC1 were studied, the predicted value and measured value were also contrasted. The results show the optimal culture conditions as follows: the culture time is 7 d, ornithine hydrochloride addition is 0.5% (M/V), culture temperature is 28 degrees C. Under these conditions, the yield of FGFC1 is 1 978.33 mg/L, which is consistent with the predicted value. It shows that the experiment is effective.