Antithrombotic effect of a novel tissue plasminogen activator from the venom of Gloydius brevicaudus viper

OBJECTIVE To investigate the thrombolytic and antiplatelet effects of a novel plasminogen activator from the venom of Gloydius brevicaudus viper(GBV-PA)in vitro and in vivo.METHODS Thrombolytic experiments were performed in rabbit models of ear vein thrombosis and carotid artery thrombosis,and in dog model of acute cerebral infarction.Inhibition of thrombus formation was evaluated in rat inferior vena cava thrombosis model and ferric chloride-induced arterial thrombosis.In vitro,we assayed the antithrombotic effect of GBV-PA on rabbit blood clots,euglobulin lysis time(ELT)of rabbit plasma,and on ADP-induced platelet aggregation.RESULTS GBV-PA intravenous administ ration significantly reduced vascular recanalization times of rabbit ear veins thrombosis and thrombus weight of rabbit carotid artery thrombosis.The arterial recanalization rates were dose-and time-dependently improved after administration of GBV-PA in canine acute cerebral infarction model.Thrombus length and weight was significantly reduced by GBV-PA both in rat inferior vena cava and ferric chloride-induced arterial thrombosis models.Thrombus formation of blood of rabbits they were administrated with GBV-PA was also inhibited.GBV-PA radically reduced plasma ELT of rabbit′s blood clots.ADP-induced platelet aggregation was inhibited by GBV-PA in a dose-dependent manner with a half-maximal inhibitory concentration of 19.9μg·mL-1.CONCLUSION This study demonstrates that GBV-PA is a thrombolytic and antiplatelet agent.It has significant antithrombotic effects on various in vitro and in vivo experimental models of thrombosis.The mechanisms that underline its antithrombotic effects were related to GBV-PA′s capabilities of increasing fibrinolytic activities and inhibition of platelet aggregation.

Identification of Bulbocodin D and C as novel STAT3 inhibitors and their anticancer activities in lung cancer cells

Cancer stands as one of the predominant causes of mortality globally, necessitating ongoing efforts to develop innovative therapeutics. Historically, natural products have been foundational in the quest for anticancer agents. Bulbocodin D (BD) and Bulbocodin C (BC), two bibenzyls derived from Pleione bulbocodioides (Franch.) Rolfe, have demonstrated notable in vitro anticancer activity. In human lung cancer A549 cells, the IC50s for BD and BC were 11.63 and 11.71 μmol·L^(−1), respectively. BD triggered apoptosis, as evidenced by an upsurge in Annexin V-positive cells and elevated protein expression of cleaved-PARP in cancer cells. Furthermore, BD and BC markedly inhibited the migratory and invasive potentials of A549 cells. The altered genes identified through RNA-sequencing analysis were integrated into the CMap dataset, suggesting BD’s role as a potential signal transducer and activator of transcription 3 (STAT3) inhibitor. SwissDock and MOE analyses further revealed that both BD and BC exhibited a commendable binding affinity with STAT3. Additionally, a surface plasmon resonance assay confirmed the direct binding affinity between these compounds and STAT3. Notably, treatment with either BD or BC led to a significant reduction in p-STAT3 (Tyr 705) protein levels, regardless of interleukin-6 stimulation in A549 cells. In addition, the extracellular signal-regulated kinase (ERK) was activated after BD or BC treatment. An enhancement in cancer cell mortality was observed upon combined treatment of BD and U0126, the MEK1/2 inhibitor. In conclusion, BD and BC emerge as promising novel STAT3 inhibitors with potential implications in cancer therapy.

Development and Validation of a Clinical Risk Score to Predict Immune-mediated Liver Injury Caused by Sintilimab:Assessed for Causality Using Updated RUCAM

Background and Aims:Immune-mediated liver injury is a fatal side effect of sintilimab.This study aimed to shed light on the associated risk factors and characteristics of this adverse event.Methods:The clinical records of 772 patients treated with sintilimab were retrospectively reviewed to investigate risk factors associated with sintilimab immune-related hepatotoxicity,as well as its incidence and outcome.The Roussel Uclaf Causality Assessment Method was used o identify cases of sintilimab-induced hepatotoxicity.Furthermore,logistic regressions were performed to compare the clinical and bloodwork characteristics of patients with and without immune-mediated liver injury caused by checkpoint inhibitors.Resu/ts:Of the 585 patients included in the study,71(12.1%)developed liver injury during sintili-mab use.The median RUCAM score with interquartile range was 7(6,8).Hypoproteinemia,dyslipidemia,and the pres-ence of thyroid peroxidase antibodies were risk factors for sintilimab-related hepatotoxicity.A nomogram model was constructed for sintilimab-induced immune-mediated liver injury based on these risk factors,which had a C-index value of 0.713 and a good calibration curve.When applied o patients with grade≥3 and≥4 sintilimab-induced immune-mediated liver injury,it achieved C-index values of 0.752 and 0.811,respectively.The nomogram model also showed a good prediction potential in patients≥65 years and males.Six of the patients with sintilimab-related hepatotoxicity showed improved liver function upon treatment with steroids.Conclusions:This study demonstrated that hypoproteinemia,dyslipidemia,and the presence of thyroid peroxidase antibodies were clinically feasible prognostic biomarkers to predict liver injury in patients treated with sintilimab.