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SummaryWe showed previously that reduced level of vasostatin-2 (VS-2) correlates to the presence and severity of coronary artery disease. In this study, we aimed to figure out the role of chromogranin A (CGA) derived VS-2 in the development of atherosclerosis and monocyte/macrophage recruitment. Apolipoprotein E-deficient (ApoE-/-) mice fed a high-fat diet exhibited attenuated lesion size by 65 % and 41 % in En face and aortic root Oil red O staining, MOMA-2 positive area by 64 %, respectively, in VS-2 treatment group compared with PBS group. Proinflammatory cytokines tumour necrosis factor-alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1) were all remarkably reduced in aortic tissues after VS-2 treatment. Mechanistically, in adhesion assay using intravital microscopy in vivo, VS-2 suppressed the number of leukocytes adhering to the wall of apoE-/- mice mesenteric arteries. In chemotactic assay, flow cytometry analysis of peritoneal lavage exudate from C57BL/6 mice showed VS-2 significantly decreased the recruiment number of inflammatory monocytes/macrophages in a thioglycollate-induced peritonitis model. Furthermore, fewer fluorescent latex beads labelled Ly-6Chi monocytes accumulated in aortic sinus lesions of apoE-/- mice after VS-2 treatment. In addition, according to the microarray of human monocyte/macrophage, we found VS-2 stimulation caused a dose-dependent decrease of Rac1 expression and inactivation of Pak1 in mice primary monocytes as well as THP-1 cells and inhibited MCP-1/CCL-5 induced transmigration in vitro. In conclusion, the Chromogranin A-derived VS-2 attenuates atherosclerosis in apoE-/- mice and, in addition to its anti-inflammatory property, also acts as an inhibitor in monocyte/macrophage recruitment.Supplementary Material to this article is available online at www.thrombosis-online.com.

Background: We investigated whether and to what extent the ratio between circulating fibrinogen (Fg) and its degradation products (FDP) reflects the severity of coronary artery disease (CAD) in type 2 diabetic patients. Methods: Plasma levels of Fg and FDP were determined, and Fg/FDP ratio was calculated in 344 consecutive patients with type 2 diabetes and chest pain on exertion undergoing coronary angiography. The severity of CAD was evaluated by the number of significant CAD (>50% luminal diameter narrowing) and Gensini score. Results: Plasma Fg was higher, but Fg/FDP ratio was lower in patients with significant CAD (n = 255) compared with those without (n = 89), due to a disproportionate increase in FDP. Fg and FDP correlated positively, while Fg/FDP ratio negatively, with the number of diseased coronary arteries and the tertile of Gensini score (all P values for trend < 0.01). After adjusting for age, sex, risk factors for CAD, lipid profiles, glycosylated hemoglobin A1c, creatinine, leukocyte count, and high-sensitivity C-reactive protein, Fg/FDP ratio remained an independent determinant for multivessel coronary disease (MVD) (odds ratio [OR], 0.869; 95% confidence interval [CI], 0.788-0.958, P = 0.005) and high tertile of Gensini score (OR, 0.797, 95% CI, 0.682-0.930, P = 0.004). The area under the curve of Fg/FDP ratio was larger than that of Fg for predicting the presence of MVD (0.647 vs. 0.563, P = 0.048) and Gensini score ≥ 30 (0.656 vs. 0.538, P = 0.026). Conclusions: Elevated plasma Fg and FDP level and reduced Fg/FDP ratio are associated with presence of CAD, and Fg/FDP ratio is superior to Fg in reflecting severe coronary atherosclerosis for patients with type 2 diabetes.

High-mobility group box (HMGB) family is related to inflammatory diseases. We investigated whether serum HMGB2 levels are related to myocardial infarction (MI) severity and major adverse cardiac events (MACE) during MI. We included 432 consecutive patients with ST-segment elevation myocardial infarction and 312 controls. Serum HMGB2 levels were significantly higher in MI patients than in controls. Increased HMGB2 levels were associated with MACE and negatively with ejection fraction in MI patients. HMGB2 was an independent determinant of MACE in logistic regression analysis. HMGB2 protein (10 μg) or saline was injected intramyocardially in MI rats, with or without coadministration of the NADPH oxidase inhibitor apocynin. After 72 h, pathological, echocardiographic, and hemodynamic examinations showed that HMGB2 increased infarct size and worsened cardiac function in MI rats. Moreover, HMGB2 administration enhanced reactive oxygen species (ROS) production, cell apoptosis, inflammation, and autophagosome clearance impairment, which were attenuated by coadministration of apocynin or knock down of receptor for advanced glycation end products (RAGE). In conclusion, increased serum HMGB2 levels are associated with MI severity and MACE at 1 mo. HMGB2 promotes myocardial ischemic injury in rats and hypoxic H9C2 cell damage via ROS provoked by RAGE.NEW & NOTEWORTHY We demonstrate that serum high-mobility group box 2 is associated with major adverse cardiac events at 1 mo in myocardial infarction patients. Mechanistically, high-mobility group box 2 promotes reactive oxygen species production via receptor for advanced glycation end products signaling in ischemic myocardium, thereby aggravating cell apoptosis, inflammation, and autophagosome clearance impairment. This study reveals that high-mobility group box 2 is a novel factor enhancing ischemic injury in myocardial infarction.