Rational Design and Testing of Antibacterial Aloe Vera Hemostatic Hydrogel

Bleeding resulting from surgical procedures or trauma, including gunshot wounds, represents a life-threatening health issue. Therefore, the development of safe, effective, and convenient hemostatic agents is critical in securing the "golden time" to save patients' lives. Plant-derived compounds and plant extracts have been regarded as promising sources of hemostatic agents in previous studies, regulating hemostatic function with low toxicity and minimal side effects within the human body. Aloe vera-based hydrogels, which are characterized by flexible strength and high functionality, have emerged as a promising platform for wound applications due to their unique biocompatibility features. This study provides a comprehensive exploration of the utilization of thickening agents and natural agents such as xanthan gum, carrageenan, Carbomer, and alginate in applying aloe vera-based hydrogels as a hemostatic. Furthermore, it also tests the use of aloe vera-based hydrogels for therapeutic delivery at wound sites through the incorporation of various antimicrobial agents to extend the utility of the hydrogels beyond hemostasis. Our novel applied research utilizes aloe vera-based hydrogel as an antimicrobial hemostatic agent, providing valuable insights for a wide range of applications and highlighting its potential to enhance hemorrhage control in various emergency scenarios.

Potential hemostatic compounds targeting urokinase plasminogen activator explored from three Euphorbiaceae species: Euphorbia maculata, Euphorbia humifusa, and Acalypha australis, with bio-affinity ultrafiltration UPLC-MS

INTRODUCTION

Numerous species of the Euphorbiaceae family, including Euphorbia maculata, Euphorbia humifusa, and Acalypha australis, have been used to manage bleeding disorders. However, few investigations have demonstrated their hemostatic potential, and their procoagulant compounds remain elusive.

OBJECTIVE

This study aimed to determine the most active procoagulant extracts from the three species' crude extract (CE) and fractions in order to screen out the active compounds and to analyze their possible mechanisms of action.

METHODS

An integrative approach, comprising prothrombin time and activated partial thromboplastin time evaluations and urokinase-type plasminogen activator (uPA) inhibitory assessment, followed by bio-affinity ultrafiltration paired with UPLC/QTOF-MS targeting uPA and docking simulations, was used.

RESULTS

The extracts with highest procoagulant activity were the CE for both E. maculata (EMCE) and E. humifusa (EHCE) and the n-butanol fraction (NB) for A. australis (AANB). The most promising ligands, namely, isoquercetin, orientin, rutin, and brevifolin carboxylic acid, were selected from these lead extracts. All of these compounds exhibited pronounced specific binding values to the uPA target and showed tight intercalation with the crucial side chains forming the uPA active pocket, which may explain their mode of action. The activity validation substantiated their hemostatic effectivity in inhibiting uPA as they had better inhibition constant (Ki) values than the reference drug tranexamic acid.

CONCLUSION

Collectively, the integrative strategy applied to these three species allowed the elucidation of the mechanisms underlying their therapeutic effects on bleeding disorders, resulting in the fast detection of four potential hemostatic compounds and their mode of action.

Chitosan-PEG Gels Loaded with Jatropha mollissima (Pohl) Baill. Ethanolic Extract: An Efficient and Effective Biomaterial in Hemorrhage Control

A lack of control over blood loss can have catastrophic implications, including death. Although several hemostatic medications have been employed to reduce bleeding, a vast majority of them are ineffective, expensive, or pose health risks to the patient. To overcome these constraints, chitosan-polyethylene glycol (CS-PEG) hemostatic gels loaded with ethanolic extract of Jatropha mollissima sap (EES) were prepared and their hemostatic, physicochemical, and cytotoxic properties were evaluated. The gels were produced by mixing CS with PEG (an external plasticizer) and EES. The phytochemical analysis revealed a significant concentration of total polyphenols and tannins content in the extract and catechin was identified as one of the key compounds of EES. Infrared spectroscopy analysis revealed the presence of EES in the gels, as well as the chemical interaction between CS and PEG. The gels were thermally stable between 25 and 37 °C (ambient and human body temperature range), had pseudoplastic deformation behavior (rheological properties preserved after shearing), were simple to inject (compression force 30 N), and were biocompatible. In vivo experiments showed that both CS-PEG-EES gels exhibited greater hemostatic action in preventing tail hemorrhage in Wistar rats, with decreased bleeding time and blood weight compared with unloaded CS-PEG gels (control groups) and Hemostank, a commercial product. However, the gel prepared with acetic acid was more efficient in controlling bleeding. These findings reveal that CS-PEG-EES gels can reduce hemorrhages and are a potent, simple, and safe hemostatic agent.

Effects of Algan hemostatic agent foam in rat femoral artery injury model: A randomized animal trial

Background/Aim: Nowadays, many deaths are related to vessel injury-induced blood loss. Failure to control bleeding also increases the risk of death. This study aimed to investigate the hemostatic effects of the Algan Hemostatic Agent (AHA) foam application in a rat model in which severe femoral artery bleeding was induced. Methods: Fourteen rats were randomly assigned to two groups: (1) control (physiological saline) (n = 7) and (2) AHA foam (n = 7). The left femoral artery of the rats was incised and when the bleeding started, and the area was pressed with another sponge for 10 s in all rats. Afterwards, physiological saline solution impregnated gauze or AHA foam was placed over same area. A chronometer was started and area was checked after 2 min. If no bleeding occurred during the first 2 min of application, it was recorded as “successful”. If bleeding occurred, the same procedure was repeated up to three times. If hemostasis could not be achieved even after the third application, it was considered a failure, and “failed” was recorded. All animals were sacrificed under high anesthesia for least 10 min after the experiment. Results: Application of AHA resulted in complete (100%) control of bleeding in all rats within the first 2 min. In control group, hemostasis was achieved in 1 out of 7 (14.3%) rats by the third application. Failure was recorded for the remaining six rats. The hemostatic success rate of the AHA foam was significantly higher than the rates of control group (P = 0.005). Conclusion: AHA foam is a very effective hemostatic agent and can be applied easily on vascular trauma models. Further studies are needed to elucidate hemostatic features of AHA.

Pharmacological comparison of four biopolymeric natural gums as hemostatic agents for management of bleeding wounds: preliminary in vitro and in vivo results

Background

Uncontrolled bleeding is one of the primary reasons for preventable death in both civilian trauma and military battle field. This study evaluates in vitro and in vivo hemostatic potential of four biopolymeric natural gums, namely, gum tragacanth, guar gum, xanthan gum, and gum acacia. In vitro evaluation of whole blood clotting time and erythrocyte agglutination assay were carried out. In vitro cytotoxicity studies with respect to each gum were done in human lymphocytes to ascertain percent cell viability. In vivo hemostatic potential of each gum (as sponge dressing and powder form) was evaluated in Sprague Dawley rats using tail bleeding assay and compared with commercially available hemostatic sponge. Other important parameters like (a) time taken for complete hemostasis, (b) amount of blood absorbed, (c) adherence strength of developed hemostatic dressing(s), (d) incidence of re-bleeding, and (e) survival of animals were also studied.

Results

Of the four test gums studied, xanthan gum (@3mg/ml of blood) and gum tragacanth (@35mg/ml of blood) were able to clot blood in least time (58.75±6.408 s and 59.00±2.082 s, respectively) and exhibited very good hemostatic potential in vitro. Except for xanthan gum, all other test gums did not exhibit any significant cytotoxicity at different time points till 24 h. In rat tail bleeding experiments, gum tragacanth sponge dressing and powder achieved hemostasis in least time (156.2±12.86 s and 76±12.55 s, respectively) and much earlier than commercially available product (333.3±38.84 s; p˂0.01).

Conclusion

Results indicate potential of gum tragacanth to be developed into a suitable hemostatic product.

Investigating the hemostatic effect of medicinal plant Arnebia euchroma (Royle) I.M.Johnst extract in a mouse model

ETHNOPHARMACOLOGICAL RELEVANCE

Arnebia euchroma (Royle) I.M.Johnst (AE) has been reported to be a potentially useful medicinal herb for the treatment of several circulatory diseases in traditional Chinese medicine. It shows effects such as "cooling of the blood," promotion of blood circulation, detoxification, and rash clearance.

AIM OF THE STUDY

To explore the hemostatic effect of the ethyl acetate extract of AE in mice.

MATERIALS AND METHODS

In this study, we explored the effects of AE on bleeding time, blood coagulation time, platelet count, and blood coagulation parameters in normal Kunming mice. Different doses of the AE extract (5, 10, and 20 g kg^-1·day^-1) were administered to mice for 14 days. Sodium carboxymethyl cellulose (CMC-Na at 0.5%) and Yunnan Baiyao (0.8 g kg^-1·day^-1) were administered as negative and positive control treatments, respectively. Bleeding time, blood coagulation time, platelet count, blood platelet aggregation, blood platelet adhesion to fibrinogen, platelet factor 4 (PF-4) secretions from blood platelets, and blood coagulation parameters including prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin time (TT), and fibrinogen (FIB) levels were measured on day 15 of administration.

RESULTS

Bleeding and blood coagulation time were significantly lower and TT was shorter in the AE extract-treated groups than in the control groups. Furthermore, FIB levels and platelet count were higher, whereas blood platelet aggregation, blood platelet adhesion to fibrinogen, and PF-4 secretion from blood platelets were more obvious in the AE extract-treated groups than in the control group. However, no significant differences were detected for PT and aPTT between the extract-treated and control groups.

CONCLUSIONS

The ethyl acetate extract of AE showed potential hemostasis effects in mice by shortening the bleeding and coagulation time. In addition, the extract increased platelet count and induced blood platelet aggregation, blood platelet adhesion to fibrinogen, PF-4 secretion from blood platelets, and FIB level, while it shortened TT.

Learning the Ropes of Platelet Count Regulation: Inherited Thrombocytopenias

Inherited thrombocytopenias (IT) are a group of hereditary disorders characterized by a reduced platelet count sometimes associated with abnormal platelet function, which can lead to bleeding but also to syndromic manifestations and predispositions to other disorders. Currently at least 41 disorders caused by mutations in 42 different genes have been described. The pathogenic mechanisms of many forms of IT have been identified as well as the gene variants implicated in megakaryocyte maturation or platelet formation and clearance, while for several of them the pathogenic mechanism is still unknown. A range of therapeutic approaches are now available to improve survival and quality of life of patients with IT; it is thus important to recognize an IT and establish a precise diagnosis. ITs may be difficult to diagnose and an initial accurate clinical evaluation is mandatory. A combination of clinical and traditional laboratory approaches together with advanced sequencing techniques provide the highest rate of diagnostic success. Despite advancement in the diagnosis of IT, around 50% of patients still do not receive a diagnosis, therefore further research in the field of ITs is warranted to further improve patient care.

Inherited platelet function disorders. Diagnostic approach and management

Inherited platelet function disorders (IPFDs) make up a significant proportion of congenital bleeding diatheses, but they remain poorly understood and often difficult to diagnose. Therefore, a rational diagnostic approach, based on a standardized sequence of laboratory tests, with consecutive steps of increasing level of complexity, plays a crucial role in the diagnosis of most IPFDs. In this review we discuss a diagnostic approach through platelet phenotyping and genotyping and we give an overview of the options for the management of bleeding in these disorders and an account of the few systematic studies on the bleeding risk associated with invasive procedures and its treatment.