Qualitative scanning electron microscopy analysis of fibrin networks and platelet abnormalities in diabetes

Abstract

Diabetes is a condition defined by hyperglycaemia and these patients have a high risk of thrombosis. Previous research showed that ultrastructural changes in clot formation occur in patients in whom there are changes in the coagulation system due to, for example, an inflammatory condition. In the current study, the ultrastructures of platelets and fibrin networks were investigated in 25 diabetic patients. Plasma smears, with and without the addition of thrombin, were prepared. Results indicated that the fibrin network in all diabetic patients had thickened masses of thin, minor fibres over the major fibres, a profile typical of an inflammatory condition. A changed platelet membrane ultrastructure could also be observed in the diabetic patients that revealed typical apoptotic morphology, in whom membrane blebbing could be seen. It can, therefore, be concluded that in diabetic patients, the ultrastructure of fibrin networks show a typical systemic inflammatory profile, although platelets seem to be apoptotic.

Carbon monoxide: Anticoagulant or procoagulant?

“…A similar increase in clot matrix density and fine fiber formation was observed in PPP obtained from smokers as determined by scanning electron microscopy (SEM) [83]. Using PRP, Pretorius and colleagues demonstrated by SEM the formation of not just finer fibers, but also sheet-like matting of thrombus ultrastructure in the settings of smoking [84], type II diabetes mellitus [85] and rheumatoid arthritis [86]. Representative SEM figures of normal PRP and the preceding three conditions are represented (Fig.…”

“…Investigations of platelet poor plasma (PPP) or platelet rich plasma (PRP) obtained from samples exposed to CORM-2 [50], obtained from smokers [83,84], obtained from patients with type II diabetes mellitus [85], and rheumatoid arthritis [86] all display similar Nielsen et al 16 16 features that may be secondary to CO exposure compared to normal subject plasma.…”

“…Representative SEM figures of normal PRP and the preceding three conditions are represented (Fig. 4), with methods used to generate these images as previously cited [84][85][86]. Considered together, these investigations involved conditions or disease states wherein increased CO would be expected to be present, resulting in thrombus ultrastructure (e.g., finer or matted fibers) consistent with enhanced clot strength demonstrated in vitro [48,[51][52][53][54][55][56][57]67,68,[70][71][72][73][74][75][76] or in vivo [68,69] following CO exposure.…”

Iron and carbon monoxide enhance coagulation and attenuate fibrinolysis by different mechanisms

“…Their serum ferritin (range 13-28 ng/ml) and percentage of iron saturation of ferritin (range 19-33%) were within normal range. As previously presented [23,24,32], 40 ml of whole blood was collected and anticoagulated with sodium citrate (nine parts blood to one part 0.105 mol/l sodium citrate), and platelet-rich plasma (PRP) was obtained from each collected sample by centrifuging the whole blood at 1250g for 2 min.…”

“…HO-1 activity is also increased systemically in inflammatory disorders associated with thrombophilia, such as diabetes mellitus [21] and rheumatoid arthritis [22]. Critically, SEM-based investigations demonstrated that the fibrin matrix formed from blood obtained from individuals with diabetes mellitus [23] or rheumatoid arthritis [24] was very similar to that observed when normal blood was exposed to ferric chloride [2][3][4][5][6][7]. In a complementary fashion, using a viscoelastic methodology validated to detect carbon monoxide-mediated hypercoagulability in the setting of tobacco smoking [25], it was determined that a patient with a clotted ventricular assist device and hemolysis had carbon monoxide-mediated hypercoagulability, and upregulation of HO-1 was documented by increased carboxyhemoglobin concentrations [26].…”