ASC regulates platelet activation and contributes to thrombus formation independent of NLRP3 inflammasome
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Authors: Watanabe, Sachiko; Usui-Kawanishi, Fumitake; Komada, Takanori; Karasawa, Tadayoshi; Kamata, Ryo; Yamada, Naoya; Kimura, Hiroaki; Dezaki, Katsuya; Ohmori, Tsukasa; Takahashi, Masafumi
Abstract
Background: Platelets are critical mediators of vascular homeostasis and thrombosis, and also contribute to the development of inflammation. NLRP3 inflammasome is a cytosolic multi-protein complex that consists of NLRP3, ASC and caspase-1, and regulates IL-1 beta-mediated inflammation. Method and Results: Using two mouse models of thrombosis (i.e., occlusion of the middle cerebral artery and inferior vena cava), we found that thrombus formation was significantly enhanced in ASC-deficient (ASC(-/-)) mice, compared to that in wild-type (WT) and IL-1 beta(-/-) mice. ASC deficiency had no effects on blood coagulation parameters (i.e., prothrombin time [PT] and activated partial thromboplastin time [APTT]). Platelets from WT mice express ASC, but neither NLRP3 nor caspase-1. ASC deficiency significantly enhanced the expression of P-selectin and GPIIb/IIIa in response to a GPVI agonist (collagen-related peptide [CRP]), but not to thrombin, in platelets. CRP induced ASC speck formation in WT platelets. ASC deficiency also enhanced cytosolic Ca2+ elevation and phosphorylation of ERK1/2 and Akt in platelets. Conclusion: Our results demonstrate that ASC negatively regulates GPVI signaling in platelets and enhances thrombus formation, independent of NLRP3 inflammasome and IL-1 beta, and provide novel insights into the link between inflammation and thrombosis. (C) 2020 Elsevier Inc. All rights reserved.
Spatholobi Caulis dispensing granule reduces deep vein thrombus burden through antiinflammation via SIRT1 and Nrf2
PHYTOMEDICINE
Authors: Tang, Ping; Liu, Han; Lin, Bingqing; Yang, Wei; Chen, Wenpei; Lu, Ziqi; Li, Peng; Gui, Shuhua; Zhan, Yaxian; Lin, Baoqin
Abstract
Background: Deep vein thrombosis (DVT) is a kind of blood stasis syndrome. Spatholobi Caulis (SC) has been widely used for the treatment of blood stasis syndrome in China, but the underlying mechanism remains poorly understood. Purpose: The aim of present study was to investigate the anti-DVT mechanism of Spatholobi Caulis dispensing granule (SCDG). Study design/methods: A rat model of inferior vena cava (IVC) stenosis-induced DVT and a cell model of oxygen-glucose deprivation (OGD) were performed. Rats were orally administered with SCDG solution once daily for seven consecutive days. IVC stenosis-induced DVT was operated on the sixth day. Thrombi were harvested and weighed on the seventh day. Pathological changes were observed by hematoxylin-eosin (HE) staining. Tumor necrosis factor (TNF)-alpha and interleukin (IL)-1 beta of serum were analyzed by enzyme-linked immunosorbent assay. C-reactive protein (CRP) was measured with turbidimetric immunoassay. Protein expressions in thrombosed IVCs and/or OGD-stimulated EA. hy926 cells were evaluated by western blot and/or immunofluorescence analyses. Results: SCDG dramatically decreased thrombus weight. SCDG decreased tissue factor (TF) protein expression, inflammatory cells influxes in thrombosed vein wall and serum levels of inflammatory cytokines and CRP. Further, SCDG up-regulated Sirtuin 1 (SIRT1) protein expression and down-regulated acetylated-NF-kappa B p65 (Ace-p65) protein expression. Moreover, SCDG up-regulated nuclear factor-erythroid 2 related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) protein expressions, and down-regulated phosphorylated-NF-kappa B p65 (p-p65) protein expression. In the OGD cell model, SCDG medicated serum decreased the protein expression of TF. SCDG medicated serum enhanced SIRT1 protein expression and reduced Ace-p65 nuclear protein expression. SCDG medicated serum promoted protein expressions of nuclear Nrf2 and total HO-1, and inhibited translocation of p65. Furthermore, inhibiting SIRT1 and Nrf2 reversed the protective effect of SCDG medicated serum on OGD-induced EA. hy926 cells. Conclusion: SCDG may prevent DVT through antiinflammation via SIRT1 and Nrf2.