Heparin, urokinase, and ancrod alter neutrophil function

Batroxobin in combination with anticoagulation may promote venous sinus recanalization in cerebral venous thrombosis: A real-world experience

Aims

The objective of this study was to evaluate cerebral venous recanalization with magnetic resonance black‐blood thrombus imaging (MRBTI) in patients with cerebral venous thrombosis (CVT) who underwent batroxobin treatment in combination with anticoagulation.

Methods

A total of 31 CVT patients were enrolled in this real‐world registry study. The patients were divided into batroxobin (n = 21) and control groups (n = 10). In addition to the same standard anticoagulation as in the control group, patients in the batroxobin group underwent intravenous batroxobin for a total of three times.

Results

In the batroxobin group compared with the control group, we found better odds of recanalization degree [adjusted OR (95%CI) of 8.10 (1.61‐40.7)] and segment‐stenosis attenuation [adjusted OR (95%CI) of 4.48 (1.69‐11.9)] with batroxobin treatment. We further noted a higher ratio of patients with the attenuation of stenosis [adjusted OR (95%CI) of 26.4 (1.10‐635)]; as well as a higher ratio of segments with stenosis reversion [adjusted OR (95%CI) of 4.52 (1.48‐13.8)]. However, neurological deficits between the two groups showed no statistical difference at 90‐day follow‐up (P > 0.05).

Conclusions

Batroxobin may promote venous sinus recanalization and attenuate CVT‐induced stenosis. Further randomized study of this promising drug may be warranted to better delineate the amount of benefit.

The efficacy and safety of Batroxobin in combination with anticoagulation on cerebral venous sinus thrombosis

Cerebral venous sinus thrombosis (CVST) is an uncommon subtype of stroke with highly variable clinical presentation. Although anticoagulation with heparin and/or warfarin remains the standard treatment for CVST, treatment failure is still common. This study aims to evaluate the safety and efficacy of Batroxobin in combination with anticoagulation on CVST control. In this retrospective study, a total of 61 CVST patients were enrolled and divided into Batroxobin (n = 23) and control (n = 38) groups. In addition to the same standard anticoagulation in control, patients in the treatment group received Batroxobin 5 BU intravenous infusion (10 BU for the first time) every other day, for a total of three infusions. A higher recanalization rate was found in Batroxobin group (adjusted OR [95% CI] of 2.5 [1.1-5.0], p = 0.028) compared to the control group, especially in patients with high levels of fibrinogen (adjusted OR [95% CI] of 4.7 [1.4-16.7], p = 0.015). Statistically significant differences between the two groups were seen regarding the levels of thrombin time, fibrinogen and D-dimer at each cut-off time point (all p < 0.01). Compared with baseline, NIHSS scores at discharge showed significant improvement in the Batroxobin group [0(0, 4.25)-5(2, 11), p = 0.036]. No significant difference in mRS scores was found between the two groups at discharge or at 6-month outpatient follow-up (all p > 0.05). Additionally, Batroxobin did not increase the risk of intracranial hemorrhage. We conclude that Batroxobin is a potentially safe and effective adjunct therapeutic agent promoting CVST recanalization especially in patients with high level of fibrinogen.

Pharmacology of Heparin and Related Drugs

Heparin has been recognized as a valuable anticoagulant and antithrombotic for several decades and is still widely used in clinical practice for a variety of indications. The anticoagulant activity of heparin is mainly attributable to the action of a specific pentasaccharide sequence that acts in concert with antithrombin, a plasma coagulation factor inhibitor. This observation has led to the development of synthetic heparin mimetics for clinical use. However, it is increasingly recognized that heparin has many other pharmacological properties, including but not limited to antiviral, anti-inflammatory, and antimetastatic actions. Many of these activities are independent of its anticoagulant activity, although the mechanisms of these other activities are currently less well defined. Nonetheless, heparin is being exploited for clinical uses beyond anticoagulation and developed for a wide range of clinical disorders. This article provides a "state of the art" review of our current understanding of the pharmacology of heparin and related drugs and an overview of the status of development of such drugs.

Evaluation of neutrophil function during hemodialysis treatment in healthy dogs under anesthesia with sevoflurane

This study evaluated the number and function of neutrophils during 3 hr of hemodialysis in healthy dogs under anesthesia. Isolated neutrophils were used to assess neutrophil adhesion, phagocytosis and the oxidative burst. At 0.5 and 3 hr after the start of hemodialysis treatment, there was a decrease in neutrophil number. The phagocytic ability of neutrophils was decreased 3 hr after the start of hemodialysis. In conclusion, this study demonstrated that hemodialysis reduces the number and phagocytic ability of neutrophils during treatment. However, these changes recover within 24 hr of hemodialysis.

Heparin and related drugs: beyond anticoagulant activity

Heparin has been widely used as an anticoagulant for more than 80 years. However, there is now considerable evidence that heparin also possesses anti-inflammatory activity, both experimentally and clinically. Importantly in many instances, the anti-inflammatory actions of heparin are independent of anticoagulant activity raising the possibility of developing novel drugs based on heparin that retain the anti-inflammatory activity. Heparin exhibits anti-inflammatory activities via a variety of mechanisms including neutralization of cationic mediators, inhibition of adhesion molecules, and the inhibition of heparanase, all involved in leukocyte recruitment into tissues. It is anticipated that furthering our understanding of the anti-inflammatory actions of heparin will lead to the development of novel anti-inflammatory drugs for a variety of clinical indications.

Inhibition of superoxide production in human neutrophils by combinations of heparin and thrombolytic agents

OBJECTIVE

To investigate the effect of heparin and thrombolytic agents on superoxide generation by human neutrophils, as inhibition of superoxide production may have a role in reducing ischaemia and reperfusion injury.

METHODS

Neutrophil superoxide production stimulated by phorbol myristate acetate (PMA), opsonised zymosan, or formyl methionyl leucyl phenylalanine (FMLP) was measured as the superoxide dismutase inhibitable reduction of acetyl ferricytochrome c by a microtitre plate technique.

RESULTS

Heparin, at concentrations of 0.5-500 U/ml, caused a gradual inhibition of superoxide production stimulated by PMA, opsonised zymosan, or FMLP. Tissue plasminogen activator was more potent than heparin in inhibiting superoxide production induced by opsonised zymosan or FMLP, but it did not affect the activity stimulated by PMA. Streptokinase or urokinase had no effect on superoxide production. When heparin was used in combination with tissue plasminogen activator, streptokinase, or urokinase at their therapeutic concentrations there was a significant inhibition of superoxide generation (70%, 30%, and 25%, respectively). The therapeutic concentrations of tissue plasminogen activator alone caused a reduction of 40% of neutrophil superoxide production. When tissue plasminogen activator and streptokinase were both added to neutrophils, however, a synergistic inhibition of 80% was achieved.

CONCLUSIONS

The inhibition of super oxide generation by these drug combinations may explain the limited inflammatory response and reduction of reperfusion injury observed in patients receiving thrombolytic treatment.

Chemotactic activity of human polymorphonuclear leukocytes and industrial xenobiotics: a brief review

This review deals with some of our contributions to the use of chemotaxis, as a tool in evaluating effects of industrial xenobiotics on PMN, either in vitro or ex vivo. In vitro experiments have shown that lead, arsenic, styrene and 2,5-hexanedione, a major neurotoxicant metabolite of n-hexane, reduce chemotaxis. The most important results of ex vivo experiments have confirmed those obtained in vitro with styrene and 2,5-hexanedione: a significant reduction of chemotaxis was indeed observed in PMN harvested from workers exposed to low levels of n-hexane or styrene who did not show any sign of biochemical or clinical alteration. After 3 weeks under non-exposed conditions, the chemotactic indexes were markedly increased in most of the workers which were exposed to styrene and in all the workers exposed to n-hexane, all of whom have shown a reduced chemotaxis at the first blood sampling. Moreover chemotaxis was found to be significantly reduced at relative low levels of lead: results of the in vitro and ex vivo experiments show a comparable ranking of midpoint inhibition concentrations. We are only at the dawn of the understanding of the relation between occupational xenobiotics and PMN chemotaxis. This research area is still promising for the future, since PMN chemotaxis seems to be adequate and it must therefore enter in well-defined study protocols for investigating the potential immunotoxicity of occupational chemicals to which humans are exposed at low levels.