Tissue factor (TF) expressed in cancer cells has been linked to tumor-associated thrombosis, a major cause of mortality in malignancy. Hypoxia is a common feature of solid tumors and can upregulate TF. In this study, the effect of YC-1, a putative inhibitor of hypoxia-inducible factor-1α (HIF-1α), on hypoxia-induced TF expression was investigated in human lung cancer A549 cells. YC-1 selectively prevented hypoxia-induced TF expression and procoagulant activity without affecting the basal TF levels. Surprisingly, knockdown or pharmacological inhibition of HIF-1α failed to mimic YC-1′s effect on TF expression, suggesting other mechanisms are involved. NF-κB, a transcription factor for TF, and its upstream regulator p38, were activated by hypoxia exposure. Treatment of hypoxic A549 cells with YC-1 prevented the activation of both NF-κB and p38. Inhibition of p38 suppressed hypoxia-activated NF-κB, and inhibited TF expression and activity to similar levels as treatment with an NF-κB inhibitor. Furthermore, stimulation of p38 by anisomycin reversed the effects of YC-1. Taken together, our results suggest that YC-1 prevents hypoxia-induced TF in cancer cells by inhibiting the p38/NF-κB pathway, this is distinct from the conventional anticoagulants that systemically inhibit blood coagulation and may shed new light on approaches to treat tumor-associated thrombosis.

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The jelly from achenes of Ficus pumila var. awkeotsang (FPAA) is a famous beverage ingredient in Taiwan. In this work, ficumarin (1), a new compound was obtained from its twigs (FPAT) and elucidated with comprehensive spectroscopic data. The biosynthetic origin was proposed from the p -coumaroyl-CoA pathway. Alloxanthoxyletin, betulinic acid, and catechin were identified as the major and active constituents responsible for relieving neutrophilic inflammation by FPAT. Among them, the most potent alloxanthoxyletin was found to interact with PRO350 and GLU377 of human INOSOX. Further, Nrf2 activating capacity of the FPAT fraction and its coumarins was confirmed. With the analysis of LC-MS/MS data and feature-based molecular networking, coumarins were found as the dominant and responsible components. Notably, alloxanthoxyletin increased Nrf2 expression by up to 816.8 ± 58% due to the interacting with the VAL561, THR560 and VAL420 residues of 5FNQ protein. COVID-19 Docking Server simulation indicated that pyranocoumarins would promisingly interfere with the life cycle of SARS-CoV-2. FPAT was proven to exert anti-inflammatory activity on neutrophils and to activate Nrf2, and may likely be developed as a complementary supplement in the treatment of COVID-19 patients.

Lactic acid bacteria have functions in immunoregulation, antagonism, and pathogen inhibition. The purpose of this study was to evaluate the effectiveness of lactic acid bacteria (LAB) in countering oral pathogens and develop related products. After a series of assays to 450 LAB strains, 8 heat-inactivated strains showed a strong inhibitory effect on a caries pathogen, Streptococcus mutans, and 308 heat-inactivated LAB strains showed a strong inhibitory effect on a periodontal pathogen, Porphyromonas gingivalis. The key reasons for inhibiting oral pathogens were bacteriocins produced by LAB and the coaggregation effect of the inactivated cells. We selected Lacticaseibacillus (Lb) paracasei 111 and Lb.paracasei 141, which had the strongest inhibitory effects on the above pathogens, was the main oral health food source. The optimal cultural conditions of Lb. paracasei 111 and Lb. paracasei 141 were studied. An oral tablet with a shelf life of 446 days made of the above strains was developed. A 40 volunteers’ clinical study (CSMUH IRB number: CS05065) was conducted with this tablet in the Periodontological Department of the Stomatology Research Center, Affiliated Hospital of Chung Shan Medical University (Taiwan). After 8 weeks of testing, 95% and 78.9% of patients showed an effect on reducing periodontal pathogens and improving probing pocket depth, respectively, in the oral tablet group.

Thrombin exosite-1 mediates the specific binding of thrombin with fibrinogen and protease-activated receptor (PAR) 1. Exosite-1 inhibitors have been shown to effectively decrease the clotting activity of thrombin, while their antiplatelet effects are relatively weak. In the present study, the inhibitory effects of two exosite-1 inhibitors, hirugen and HD1, but not the exosite-2 inhibitor HD22, on thrombin-induced platelet aggregation and P-selectin expression were dramatically enhanced by a PAR4 antagonist, YD-3. In contrast, the PAR1 antagonist SCH-79797 did not affect the antiplatelet effects of exosite-1 inhibitors. The exosite-1 inhibitors and YD-3 prevented the Ca2+ spike and the prolonged Ca2+ response in thrombin-stimulated platelets, respectively; and combination of these two classes of agents led to abolishment of Ca2+ signal. Unlike exosite-1 inhibitors, the antiplatelet effects of the active site inhibitor PPACK and the bivalent inhibitor bivalirudin were not significantly enhanced by YD-3. In addition, the platelet-stimulating activity of γ-thrombin, an autolytic product of α-thrombin which lacks exosite-1, was inhibited by YD-3. These results suggest that the synergistic antiplatelet effects of exosite-1 inhibitor and PAR4 antagonist are resulted from combined blockade of PAR1 and PAR4 in platelets. In fibrinogen or plasma clotting assay, YD-3 neither prolonged the clotting time on its own nor enhanced the anticoagulant activity of exosite-1 inhibitors. Therefore, the combined blockade of exosite-1 and PAR4 may offer a potential strategy for improving the balance of benefits and risks of antithrombotic therapy.