Nanomedicines for hemorrhage control

Platelet-inspired synthetic nanoparticles improve hemostasis and hemodynamics in a rabbit model of abdominal hemorrhage

BACKGROUND

Early platelet transfusion is associated with reduced mortality in traumatic hemorrhage. However, platelet usage is severely limited because of the challenges of donor availability, platelet portability, and storage. Here, we report on a bioinspired synthetic platelet (SP) nanoconstruct that utilizes liposome surface-decoration with peptides that mimic injury site-specific platelet adhesion to von Willebrand Factor and collagen, and fibrinogen-mediated platelet aggregation. Synthetic platelet has previously shown promising hemostatic outcomes in vitro and in vivo. Here, we evaluated hemostasis and hemodynamic effects of SP in a rabbit model of abdominal hemorrhage.

METHODS

Twenty-three adult male New Zealand white rabbits (2.5-3.5 kg) were treated with either buffer, control particles (CPs), or SP. Under general anesthesia with invasive monitoring, rabbits underwent laparotomy with combined splenic and hepatic injury. Hemodynamics were monitored for 30 minutes and blood loss was quantified. Blood counts, aggregometry, catecholamine and platelet factor 4 (PF4) assays were performed at multiple timepoints. Analysis used analysis of variance and post hoc Tukey testing with α = 0.05.

RESULTS

Rabbits in the SP (n = 7) group had significantly lower weight-normalized blood loss compared with both buffer (n = 8) and CP (n = 8) animals (21.1 vs. 33.2 vs. 40.4 g/kg, p < 0.001). Synthetic platelet-treated animals had higher systolic blood pressure area under curve compared with buffer- and CP-treated animals (1567 vs. 1281 vs. 1109 mm Hg*min, p = 0.006), although post hoc differences were only significant for the SP/CP comparison ( p = 0.005). Platelet counts, catecholamine levels, PF4, and aggregometry were similar between groups.

CONCLUSION

Synthetic platelet treatment significantly reduced blood loss and improved hemodynamics in a rabbit abdominal hemorrhage model. Synthetic platelet has potential as an intravenous hemostatic platelet surrogate with donor-independent availability and scalable manufacture.

Rational Design of Nanomedicine for Placental Disorders: Birthing a New Era in Women's Reproductive Health

The placenta is a transient organ that forms during pregnancy and acts as a biological barrier, mediating exchange between maternal and fetal circulation. Placental disorders, such as preeclampsia, fetal growth restriction, placenta accreta spectrum, and gestational trophoblastic disease, originate in dysfunctional placental development during pregnancy and can lead to severe complications for both the mother and fetus. Unfortunately, treatment options for these disorders are severely lacking. Challenges in designing therapeutics for use during pregnancy involve selectively delivering payloads to the placenta while protecting the fetus from potential toxic side effects. Nanomedicine holds great promise in overcoming these barriers; the versatile and modular nature of nanocarriers, including prolonged circulation times, intracellular delivery, and organ-specific targeting, can control how therapeutics interact with the placenta. In this review, nanomedicine strategies are discussed to treat and diagnose placental disorders with an emphasis on understanding the unique pathophysiology behind each of these diseases. Finally, prior study of the pathophysiologic mechanisms underlying these placental disorders has revealed novel disease targets. These targets are highlighted here to motivate the rational design of precision nanocarriers to improve therapeutic options for placental disorders.

The Topical Hemostatic Materials for Coagulopathy

Medical sciences have witnessed significant progresses in hemostatic materials which have saved lives by supporting natural hemostatic ability. However, for the treatment of coagulopathy, where natural hemostatic ability is dysfunctional,...

Highly resilient, biocompatible, and antibacterial carbon nanotube/hydroxybutyl chitosan sponge dressing for rapid and effective hemostasis

Uncontrolled hemorrhage is the leading cause of trauma death. The development of safe and efficient hemostatic agents that can rapidly and effectively control bleeding is of great significance to rescue the injured. However, the mechanical, absorptive, and antibacterial properties of conventional two-dimensional hemostatic agents are not satisfactory. Herein, a series of effective three-dimensional hemostatic dressings (JWCNT/HBC sponges) are developed by chemical modification of joint-welded carbon nanotube (JWCNT) sponges with hydroxybutyl chitosan (HBC) for hemorrhage hemostasis. The JWCNT/HBC sponges exhibit high elasticity, porous structure, and suitable blood-absorption and blood-maintaining performance. Moreover, the introduction of HBC endows the JWCNT/HBC sponges with favorable blood compatibility and good antibacterial activity. The sponge treated with 0.5% HBC (JWCNT/0.5%HBC sponge) displays better antiseptic capability, faster blood clotting ability in vitro and shorter hemostasis time in vivo than the commercial gelatin sponge. The JWCNT/HBC sponges combine the advantages of JWCNT sponges and HBC in the adhesion and activation of platelets and red blood cells, thus becoming a good medical material for trauma hemostasis.