Objective To analyze the effect of fisetin against venous thrombosis in rats.Methods Seventy SD rats were randomly divided into the following groups:sham-operation group,model group,fisetin 45 mg/kg,15 mg/kg,5 mg/kg groups,and aspirin group(47 mg/kg).The corresponding medication was administered by gavage once a day consecutively(the sham-operation group and the model group were given 0.5％carboxymethyl cellulose sodium solution with 10 mL/kg,respectively)for 7 consecutive days.One hour after the last administration,the rats were anesthetized,the lower part of the intersection of inferior vena cava and left renal vein was ligated with silk thread(no ligation in the sham-operation group),and the abdominal wall was sutured.Two hours later,the abdominal cavity was reopened,the other venous branches 1.5 cm away from the ligation site were closed with the artery clamp,and blood was collected from the abdominal aorta.The anticoagulant ratio of 3.8％sodium citrate∶whole blood was 1∶9.The venous thrombus 1 cm down from the ligation point of the intersection of inferior vena cava and left renal vein was cut and the thrombus was separated.The residual blood was dried with filter paper,weighed and recorded.Plasma was taken after anticoagulant blood centrifugation.The levels of plasma antithrombin-Ⅲ(AT-Ⅲ),protease C(PC),plasminogen(PLG),and plasminogen activator inhibitor(PAI-1)were detected by ELISA kits.Results Compared with the model group,the weight of thrombus in fisetin 45 mg/kg group and aspirin 47 mg/kg group decreased(P＜0.01).The content of AT-Ⅲ in three fisetin groups increased(all P＜0.05).The content of PC in fisetin 45 mg/kg increased(P＜0.05).The content of PLG and PAI-1 in fisetin 45 mg/kg group decreased(both P＜0.05).Conclusion Fisetin has the effect against venous thrombosis in vivo,and the effect is related to the upregulation of AT-Ⅲ and PC and the downregulation of PLG and PAI-1.

Objective To investigate the impact of exosomal miRNAs derived from endoplasmic reticulum-stressed(ERS)head and neck squamous cell carcinoma(HNSCC)cells on macrophages.Methods This study was reviewed and approved by the Ethics Committee.The expression levels of ERS-associated proteins,including protein kinase R-like endoplasmic reticulum kinase(PERK)and glucose-regulated protein 78(GRP78),in HNSCC tissues and para-tumor tissues were detected by Western blot(WB)and quantitative real-time PCR(RT-qPCR).HN4 human laryngeal squamous cell carcinoma cells were treated with 500 U/mL interferon-γ(IFN-γ)for 48 h to induce ER stress,and exo-somes secreted by ER-stressed HN4 cells were collected and identified.The types of miRNAs in exosomes were identi-fied through bioinformatics analysis,and the target genes of miRNAs were predicted.Macrophages were transfected with miRNA,co cultured with collected exosomes,and the expression of PTEN in macrophages was knocked down.The downstream signaling pathway regulated by exosomal miRNAs was studied by WB and RT-qPCR.Results Compared with that in para-tumor tissues,the expression level of ER stress-associated proteins in HNSCC tissues was increased(P＜0.05).RNA-seq analysis revealed that miR-26a-5p was highly upregulated in ER-stressed HN4 cell-derived exo-somes(P＜0.05).PTEN is the target gene for miR-26a-5p.miR-26a-5p increased the expression level of PD-L1 in mac-rophages and downregulated the expression of PTEN(P＜0.05).Macrophages co cultured with ERS extracellular vesi-cles showed an increase in miR-26a-5p and PD-L1 expression,a decrease in PTEN expression,and an increase in p-AKT expression(P＜0.05).Knock down the expression of PTEN in macrophages and increase the expression of PD-L1(P＜0.01).Conclusion ERS HNSCC cell-derived exosomal miR-26a-5p promotes the expression of PD-L1 in macro-phages through the PTEN/AKT signaling pathway.