Neutrophil extracellular traps exacerbate coagulation and endothelial damage in patients with essential hypertension and hyperhomocysteinemia.

Patients with essential hypertension (EH) and hyperhomocysteinemia (HHCY) suffer from more increased thrombotic events than those in EH alone. However, the underlying mechanisms for this effect are not well understood. This study hypothesized that neutrophil extracellular trap (NET) releasing may be triggered by HHCY in patients in EH, thereby predisposing them to a more hypercoagulable state. Using a modified-capture enzyme-linked immunosorbent assay (ELISA) method, we observed that cell-free DNA (CF-DNA) and myeloperoxidase DNA (MPO-DNA) in patients With EH and HHCY were significantly higher. The NET formation was also positively correlated with homocysteine levels, neutrophil-lymphocyte ratio (NLR), and hypercoagulable markers (thrombin-antithrombin complex, D-dimers). Furthermore, neutrophils from patients in EH with HHCY were found to be predisposed to amplified NET release when compared to patients in EH without HHCY or CTR. Coagulation function assays showed that NETs in patients With EH and HHCY resulted in a significantly increased ability to generate thrombin and fibrin than in those in EH without HHCY or CTR. These procoagulant effects of NETs in patients With EH and HHCY were markedly inhibited (approximately 70%) by the cleavage of NETs with DNase I. Isolated NETs from patients With EH and HHCY neutrophils also exerted a strong cytotoxic effect on endothelial cells (ECs), converted them to apoptosis. This study revealed a previously unrecognized association between the hypercoagulable state and neutrophils in patients With EH and HHCY. Therefore, blocking NETs may represent a new therapeutic objective for preventing thrombosis in these patients.

[Clinical study of heparin-induced thrombocytopenia].

OBJECTIVE: To observe the incidence of heparin-induced thrombocytopenia (HIT) in patients received unfractionated heparin (UFH) treatment, and explore the feasibility of monitoring HIT by platelet counts, as well as the significance of HIT-antibody test in HIT diagnosis. METHODS: 145 patients received UFH treatment in Vascular Surgery Department were studied. Before and after the UFH treatment, platelet counts, HIT-antibody ELISA test and heparin-induced platelet aggregation (HIPA) were tested. RESULTS: Among the 145 patients, thrombocytopenia occurred in 40 (27.6%) cases, HIT-antibody ELISA test positive in 59 (40.7%) cases, HIPA test positive in 26 (17.9%) cases. The HIT was diagnosed in 24 (16.5%) cases, and heparin-induced thrombocytopenia and thrombosis (HITTS) occurred in 5 (3.4% in all cases, and 20.8% in HIT patients). In HIT patients, 15 patients (62.5%) were thrombocytopenia, HIT-antibody positive and HIPA test positive. Platelet counts in all of the 24 patients recovered to normal or level before UFH treatment in 3-6 days after heparin withdrawal therapy. CONCLUSION: HIT can be early diagnosed by monitoring platelet counts, HIT-antibody ELISA test and HIPA test. Withdrawal of heparin therapy in time and use of alternative anticoagulant, HITTS rate might be expected to decline further.