ex-527 and Venous-Thrombosis

Whitmania pigra Whitman (W pigra), a traditional Chinese medicine, has functions of breaking stagnant and eliminating blood stasis. The aim of this study was to investigate the underlying mechanism of W pigra against deep vein thrombosis (DVT).. A rat model of DVT induced by inferior vena cava stenosis was successfully established. Rats were administered vehicle (saline solution, p.o.), three doses of W pigra aqueous extract (34.7, 104.2, or 312.5 mg crude W pigra/kg, p.o.), heparin (200 U/kg, i.v.), or clopidogrel (25 mg/kg, p.o.) once daily for 2 d. Thrombus weight and histopathological changes were examined. Blood samples were collected to determine blood cell counts, blood viscosity, blood coagulation, blood fibrinolysis, serum levels of interleukin-1β, and tumor necrosis factor-α. Protein expressions of Sirtuin1 (SIRT1), acetylated p65 (Ace-p65), and phosphorylated p65 (p-p65) were determined by Western blot. Furthermore, SIRT1-specific inhibitor EX527 was applied to confirm the role of SIRT1 in the antithrombotic effect of W pigra.. W pigra significantly decreased thrombus weight. W pigra had no effects on blood cell counts, whole blood viscosity, blood coagulation, blood fibrinolysis. However, it reduced tissue factor protein expression in the vein wall and thrombus. Moreover, it sharply increased SIRT1 protein expression and decreased leukocytes recruitment in the thrombus and vein wall, serum levels of interleukin-1β and tumor necrosis factor-α, and protein expressions of Ace-p65 and p-p65. Furthermore, the antithrombotic effect of W pigra was significantly abolished by EX527.. Aqueous extract of W pigra effectively reduced DVT burden by inhibiting inflammation via SIRT1/nuclear factor-kappa B signaling pathway.

Topics: Animals; Biological Products; Carbazoles; Cytokines; Drug Evaluation, Preclinical; Female; Inflammation; Leeches; Male; Medicine, Chinese Traditional; NF-kappa B; Rats, Sprague-Dawley; Signal Transduction; Sirtuin 1; Thromboplastin; Venous Thrombosis

 Inflammation plays an important role in thrombus formation, and Sirtuin 1 (SIRT1) negatively regulates inflammation via deacetylating nuclear factor-kappa B. However, the relationship between SIRT1-regulated inflammation and deep vein thrombosis (DVT) is still unknown..  The aim of this study was to investigate whether SIRT1 plays a critical role in inferior vena cava (IVC) stenosis-induced DVT..  Thrombus weight and histopathologic analysis of IVC were evaluated at different time points after IVC stenosis in rats. Serum levels of inflammatory cytokines and protein expressions of SIRT1, acetylated p65 (Ace-p65), phosphorylated p65 (p-p65) and tissue factor (TF) in thrombosed IVC were assessed. Besides, the effects of resveratrol (RES, a SIRT1 agonist) and EX527 (a selective SIRT1 inhibitor) on DVT were evaluated..  Thrombus weight was increased from 1 to 3 days after IVC stenosis, and then was decreased afterwards. Leukocytes infiltration appeared and serum levels of cytokines were significantly increased in rats of IVC stenosis. SIRT1 protein expression was significantly down-regulated at 1 hour and 1 day after stenosis, while p-p65, Ace-p65 and TF protein expressions appeared a contrary trend. RES reduced thrombus weight, leukocytes infiltration, levels of tumour necrosis factor-α and interleukin-1β and protein expressions of Ace-p65 and TF as well. Moreover, RES significantly increased the protein and messenger ribonucleic acid expressions of SIRT1, while EX527 abolished the protective effects of RES..  SIRT1 activation attenuated IVC stenosis-induced DVT via anti-inflammation in rats. Therefore, SIRT1 may be a potential therapeutic target that could ameliorate DVT.

Topics: Acetylation; Animals; Anti-Inflammatory Agents; Carbazoles; Disease Models, Animal; Female; Fibrinolytic Agents; Histone Deacetylase Inhibitors; Inflammation; Inflammation Mediators; Male; Phosphorylation; Rats, Sprague-Dawley; Resveratrol; Signal Transduction; Sirtuin 1; Time Factors; Transcription Factor RelA; Vena Cava, Inferior; Venous Thrombosis