Neural Injuries Induced by Hydrostatic Pressure Associated With Mass Effect after Intracerebral Hemorrhage

Piezo1 inhibitor isoquercitrin rescues neural impairment mediated by NLRP3 after intracerebral hemorrhage

In intracerebral hemorrhage (ICH), the mechanical brain injury is a considerable and indispensable factor determining the neurological functions and poor outcomes. Previous studies indicate the mechanically gated ion channel-Piezo1 can transduce mechanical effects following ICH. Isoquercitrin (ISQ) is a well-studied ion channel inhibitor. Furthermore, whether the following Piezo1-mediated neurological impairment can be ameliorated by ISQ remains unclear. Herein, we constructed the hydrostatic pressure model and ICH rat model. Firstly, we found that Piezo1 agonists Yoda1 and Jedi1 facilitated extracellular calcium influx dramatically, but ISQ could depress intracellular Ca2+ overload under hydrostatic pressure in primary neurons. Then we detected the expression profile of Piezo1, NLRP3 and NF-κB p-p65 after ICH, and found that the expression of Piezo1 was much earlier than NLRP3 and NF-κB p-p65. Furthermore, by western blot and immunofluorescence, ISQ decreased the expression of Piezo1 and NLRP3 dramatically like GsMTx4, but Nigericin as a NLRP3 agonist failed to affect Piezo1. Besides, both ISQ and interfering Piezo1 suppressed the upregulated caspase-1, NF-κB p-p65, p-IκBα, Tunel-positive cells and inflammatory factors (IL-1β, IL-6 and TNF-α) in ICH. At last, the hydrostatic pressure or hematoma induced disturbed neural viability, disordered neural cytomorphology, and increased neurobehavioral and cognitive deficits, but they were improved by ISQ and GsMTx4 strongly. Therefore, ISQ could alleviate neurological injuries induced by Piezo1 via NLRP3 pathway. These observations indicated that Piezos might be the new therapeutic targets, and blocking Piezos/NLRP3 pathway by ISQ could be an auspicious strategy for the treatment of ICH.

Intracranial Pressure Dysfunction Following Severe Intracerebral Hemorrhage in Middle-Aged Rats

Rising intracranial pressure (ICP) aggravates secondary injury and heightens risk of death following intracerebral hemorrhage (ICH). Long-recognized compensatory mechanisms that lower ICP include reduced cerebrospinal fluid and venous blood volumes. Recently, we identified another compensatory mechanism in severe stroke, a decrease in cerebral parenchymal volume via widespread reductions in cell volume and extracellular space (tissue compliance). Here, we examined how age affects tissue compliance and ICP dynamics after severe ICH in rats (collagenase model). A planned comparison to historical young animal data revealed that aged SHAMs (no stroke) had significant cerebral atrophy (9% reduction, p ≤ 0.05), ventricular enlargement (9% increase, p ≤ 0.05), and smaller CA1 neuron volumes (21%, p ≤ 0.05). After ICH in aged animals, contralateral striatal neuron density and CA1 astrocyte density significantly increased (12% for neurons, 7% for astrocytes, p ≤ 0.05 vs. aged SHAMs). Unlike young animals, other regions in aged animals did not display significantly reduced cell soma volume despite a few trends. Nonetheless, overall contralateral hemisphere volume was 10% smaller in aged ICH animals compared to aged SHAMs (p ≤ 0.05). This age-dependent pattern of tissue compliance is not due to absent ICH-associated mass effect (83.2 mm3 avg. bleed volume) as aged ICH animals had significantly elevated mean and peak ICP (p ≤ 0.01), occurrence of ICP spiking events, as well as bilateral evidence of edema (e.g., 3% in injured brain, p ≤ 0.05 vs. aged SHAMs). Therefore, intracranial compliance reserve changes with age; after ICH, these and other age-related changes may cause greater fluctuation from baseline, increasing the chance of adverse outcomes like mortality.

Role of mass effect on neuronal iron deposition after intracerebral hemorrhage

Mass effect after intracerebral hemorrhage (ICH) not only mechanically induces the brain damage, but also influences the progress of secondary brain damage. However, the influence of mass effect on the iron overload after ICH is still unclear. Here, a fixed volume of ferrous chloride solution and different volumes of poly(N-isopropylacrylamide) (PNIPAM) hydrogel were co-injected into the right basal ganglia of rats to establish the ICH model with certain degree of iron deposition but different degrees of mass effect. We found that mass effect significantly increased the iron deposition on neuronal cells at 6 h after ICH in a volume-dependent manner. Furthermore, the upregulation of Piezo-2, divalent metal transporter 1 (DMT1), transferrin receptor (TfR), and ferroptosis expressions were noted as the increase of mass effect. In addition, the pERK1/2 inhibitor PD98059 treated ICH rats reversed the upregulation of iron uptake protein and ferroptosis. Our findings revealed the relationship between mass effect and the iron uptake and ferroptosis, which are benefit to understand the brain damage process after ICH.

Piezo protein determines stem cell fate by transmitting mechanical signals

Piezo ion channel is a mechanosensitive protein on the cell membrane, which contains Piezo1 and Piezo2. Piezo channels are activated by mechanical forces, including stretch, matrix stiffness, static pressure, and shear stress. Piezo channels transmit mechanical signals that cause different downstream responses in the differentiation process, including integrin signaling pathway, ERK1/2 MAPK signaling pathway, Notch signaling, and WNT signaling pathway. In the fate of stem cell differentiation, scientists found differences in Piezo channel expression and found that Piezo channel expression is related to developmental diseases. Here, we briefly review the structure and function of Piezo channels and the relationship between Piezo and mechanical signals, discussing the current understanding of the role of Piezo channels in stem cell fate and associated molecules and developmental diseases. Ultimately, we believe this review will help identify the association between Piezo channels and stem cell fate.

Acute Magnetic Resonance Imaging Predictors of Chronic Motor Function and Tissue Sparing in Rat Cervical Spinal Cord Injury

Predicting functional outcomes from spinal cord injury (SCI) at the acute setting is important for patient management. This work investigated the relationship of early magnetic resonance imaging (MRI) biomarkers in a rat model of cervical contusion SCI with long-term functional outcome and tissue sparing. Forty rats with contusion injury at C5 at either the spinal cord midline (bilateral) or over the lateral cord (unilateral) were examined using in vivo multi-modal quantitative MRI at 1 day post-injury. The extent of T2-weighted hyperintensity reflecting edema was greater in the bilateral model compared with the unilateral injury. Diffusion tensor imaging (DTI) exhibited microscopic damage in similar regions of the cord as reductions in fractional anisotropy (FA) and mean diffusivity (MD), but DTI parameter maps were also confounded by the presence of vasogenic edema that locally increased FA and MD. In comparison, filtered diffusion-weighted imaging (fDWI) more clearly delineated the location of acute axonal damage without effects of vasogenic edema. Pairwise correlation analysis revealed that 28-day motor functional outcomes were most strongly associated with the extent of edema (R = -0.69). Principal component analysis identified close associations of motor functional score with tissue sparing, the extent of edema, lesion area, and injury type (unilateral or bilateral). Among the diffusion MRI parameters, lesion areas measured with fDWI had the strongest association with functional outcome (R = -0.41). Voxelwise correlation analysis identified a locus of white matter damage associated with function in the dorsal white matter, although this was likely driven by variance across the two injury patterns (unilateral and bilateral injury). Nonetheless, correlation with motor function within the damaged region found in the voxelwise analysis outperformed morphological lesion area measurement as a predictor of chronic function. Collectively, this study characterized anatomical and diffusion MRI signatures of acute SCI at cervical spine and their association with chronic functional outcomes and histological results.

COMPREHENSIVE STUDY OF MANIFESTATIONS OF BRAIN TISSUE RESOLUTION IN CASE OF VARIOUS TYPES OF STROKE

OBJECTIVE

The aim: The study is to research the resolution of perifocal brain tissue at various type strokes using immunomorphology.

PATIENTS AND METHODS

Materials and methods: The immunohistochemical study of perifocal brain tissue in 21 cases of various strokes types was condacted.

RESULTS

Results: When comparing the GFAP + astrocytes detection area at IS, HS and IS with HT, no significant difference was found. At the 1st degree of GFAP + astrocytes were in the border around the necrosis nucleus at IS and IS with HT, and at HS GFAP + astrocytes accumulated along the hematoma edge. CD34 + cells were found in most cases of strokes. Over time, cases with a larger CD34 + cells detection area increased (Kendal's Tau = 0.512, p = 0.001) in all groups. The capillary network at HS was around the hematoma and formed a gliomesodermal capsule with microglia and inflammation. 1st degree τ-protein accumulation was detected in 2/3 of cases (66.7%) of all strokes without significant difference. If compared in different stroke periods, -protein detection frequency increased and accumulated in brain structures - Kendal's Tau = 0.359; p = 0.023.

CONCLUSION

Conclusions: With the development of the disease, the number of cases with a larger area of detection of GFAP + astrocytes and CD34 + cells increased in strokes of various types. τ-protein was detected in neurons in all variants of ACVA in the first period.

Assessing the Evolution of Intracranial Hematomas by using Animal Models: A Review of the Progress and the Challenges

Stroke has become the second leading cause of death in people aged higher than 60 years, with cancer being the first. Intracerebral hemorrhage (ICH) is the most lethal type of stroke. Using imaging techniques to evaluate the evolution of intracranial hematomas in patients with hemorrhagic stroke is worthy of ongoing research. The difficulty in obtaining ultra-early imaging data and conducting intensive dynamic radiographic imaging in actual clinical settings has led to the application of experimental animal models to assess the evolution of intracranial hematomas. Herein, we review the current knowledge on primary intracerebral hemorrhage mechanisms, focus on the progress of animal studies related to hematoma development and secondary brain injury, introduce preclinical therapies, and summarize related challenges and future directions.

Therapeutic hypothermia for intracerebral hemorrhage: Systematic review and meta-analysis of the experimental and clinical literature

BACKGROUND

Intracerebral hemorrhage remains the deadliest form of stroke worldwide, inducing neuronal death through a wide variety of pathways. Therapeutic hypothermia is a robust and well-studied neuroprotectant widely used across a variety of specialties.

AIMS

This review summarizes results from preclinical and clinical studies to highlight the overall effectiveness of therapeutic hypothermia to improve long-term intracerebral hemorrhage outcomes while also elucidating optimal protocol regimens to maximize therapeutic effect.

SUMMARY OF REVIEW

A systematic review was conducted across three databases to identify trials investigating the use of therapeutic hypothermia to treat intracerebral hemorrhage. A random-effects meta-analysis was conducted on preclinical studies, looking at neurobehavioral outcomes, blood brain barrier breakdown, cerebral edema, hematoma volume, and tissue loss. Several mixed-methods meta-regression models were also performed to adjust for variance and variations in hypothermia induction procedures. Twwenty-one preclinical studies and five human studies were identified. The meta-analysis of preclinical studies demonstrated a significant benefit in behavioral scores (ES = -0.43, p = 0.02), cerebral edema (ES = 1.32, p = 0.0001), and blood brain barrier (ES = 2.73, p ≤ 0.00001). Therapeutic hypothermia was not found to significantly affect hematoma expansion (ES = -0.24, p = 0.12) or tissue loss (ES = 0.06, p = 0.68). Clinical study outcome reporting was heterogeneous; however, there was recurring evidence of therapeutic hypothermia-induced edema reduction.

CONCLUSIONS

The combined preclinical evidence demonstrates that therapeutic hypothermia reduced multiple cell death mechanisms initiated by intracerebral hemorrhage; yet, there is no definitive evidence in clinical studies. The cooling strategies employed in both preclinical and clinical studies were highly diverse, and focused refinement of cooling protocols should be developed in future preclinical studies. The current data for therapeutic hypothermia in intracerebral hemorrhage remains questionable despite the highly promising indications in preclinical studies. Definitive randomized controlled studies are still required to answer this therapeutic question.

Potential therapeutic effects of Nrf2 activators on intracranial hemorrhage

Intracranial hemorrhage (ICH) is a devastating disease which induces high mortality and poor outcomes including severe neurological dysfunctions. ICH pathology is divided into two types: primary brain injury (PBI) and secondary brain injury (SBI). Although there are numerous preclinical studies documenting neuroprotective agents in experimental ICH models, no effective drugs have been developed for clinical use due to complicated ICH pathology. Oxidative and inflammatory stresses play central roles in the onset and progression of brain injury after ICH, especially SBI. Nrf2 is a crucial transcription factor in the anti-oxidative stress defense system. Under normal conditions, Nrf2 is tightly regulated by the Keap1. Under ICH pathological conditions, such as overproduction of reactive oxygen species (ROS), Nrf2 is translocated into the nucleus where it up-regulates the expression of several anti-oxidative phase II enzymes such as heme oxygenase-1 (HO-1). Recently, many reports have suggested the therapeutic potential of Nrf2 activators (including natural or synthesized compounds) for treating neurodegenerative diseases. Moreover, several Nrf2 activators attenuate ischemic stroke-induced brain injury in several animal models. This review summarizes the efficacy of several Nrf2 activators in ICH animal models. In the future, Nrf2 activators might be approved for the treatment of ICH patients.

Behavioral and Neuronal Effects of Inhaled Bromine Gas: Oxidative Brain Stem Damage

The risk of accidental bromine (Br2) exposure to the public has increased due to its enhanced industrial use. Inhaled Br2 damages the lungs and the heart; however, adverse effects on the brain are unknown. In this study, we examined the neurological effects of inhaled Br2 in Sprague Dawley rats. Rats were exposed to Br2 (600 ppm for 45 min) and transferred to room air and cage behavior, and levels of glial fibrillary acidic protein (GFAP) in plasma were examined at various time intervals. Bromine exposure resulted in abnormal cage behavior such as head hitting, biting and aggression, hypervigilance, and hyperactivity. An increase in plasma GFAP and brain 4-hydroxynonenal (4-HNE) content also was observed in the exposed animals. Acute and delayed sympathetic nervous system activation was also evaluated by assessing the expression of catecholamine biosynthesizing enzymes, tryptophan hydroxylase (TrpH1 and TrpH2), and tyrosine hydroxylase (TyrH), along with an assessment of catecholamines and their metabolites. TyrH was found to be increased in a time-dependent manner. TrpH1 and TrpH2 were significantly decreased upon Br2 exposure in the brainstem. The neurotransmitter content evaluation indicated an increase in 5-HT and dopamine at early timepoints after exposure; however, other metabolites were not significantly altered. Taken together, our results predict brain damage and autonomic dysfunction upon Br2 exposure.

The Story of Intracerebral Hemorrhage: From Recalcitrant to Treatable Disease

This invited special report is based on an award presentation at the World Stroke Organization/European Stroke Organization Conference in November of 2020 outlining progress in the acute management of intracerebral hemorrhage (ICH) over the past 35 years. ICH is the second most common and the deadliest type of stroke for which there is no scientifically proven medical or surgical treatment. Prospective studies from the 1990s onward have demonstrated that most growth of spontaneous ICH occurs within the first 2 to 3 hours and that growth of ICH and resulting volumes of ICH and intraventricular hemorrhage are modifiable factors that can improve outcome. Trials focusing on early treatment of elevated blood pressure have suggested a target systolic blood pressure of 140 mm Hg, but none of the trials were positive by their primary end point. Hemostatic agents to decrease bleeding in spontaneous ICH have included desmopressin, tranexamic acid, and rFVIIa (recombinant factor VIIa) without clear benefit, and platelet infusions which were associated with harm. Hemostatic agents delivered within the first several hours have the greatest impact on growth of ICH and potentially on outcome. No large Phase III surgical ICH trial has been positive by primary end point, but pooled analyses suggest that earlier ICH removal is more likely to be beneficial. Recent trials emphasize maximization of clot removal and minimizing brain injury from the surgical approach. The future of ICH therapy must focus on delivery of medical and surgical therapies as soon as possible if we are to improve outcomes.

Role of mass effect and trehalose on early erythrolysis after experimental intracerebral hemorrhage

The mechanisms of brain injury after intracerebral hemorrhage (ICH) involve mass effect-induced primary injury and secondary injury caused by a pathologic response to the hematoma. Considerable attentions have recently been paid to the mechanisms and therapeutic strategy for secondary brain injury due to no overall benefit from early surgery compared with initial conservative treatment. However, it is unclear whether there is a causal relationship between mass effect and secondary brain injury. Here, the role of mass effect on early erythrolysis after experimental ICH was investigated based on the poly(N-isopropylacrylamide) (PNIPAM) ICH model. Autologous blood and PNIPAM hydrogel were co-injected into the right basal ganglia of rats to induce different degrees of mass effect, but with a constant hematoma. The influences of different mass effect and time courses on erythrolysis and brain damages after ICH were investigated. Furthermore, the protective effect of trehalose against erythrolysis after ICH was evaluated. The results showed that mass effect caused erythrocyte morphological change at 24 hr after ICH. The released hemoglobin was quantitatively evaluated by a polynomial concerning with the mass effect, the volume of hematoma, and the time of ICH. An obvious increase in heme oxygenase-1 (HO-1) and ionized calcium binding adaptor molecule-1 (Iba-1) expression, iron deposition, cell death, and neurological deficits was observed with increasing mass effect. Moreover, trehalose alleviated brain injury by inhibiting erythrolysis after ICH. These data demonstrated that mass effect accelerated the erythrolysis and brain damages after ICH, which could be relieved through trehalose therapy.

Mesenchymal Stem Cells Transplantation in Intracerebral Hemorrhage: Application and Challenges

Intracerebral hemorrhage (ICH) is one of the leading causes of death and long-term disability worldwide. Mesenchymal stem cell (MSC) therapies have demonstrated improved outcomes for treating ICH-induced neuronal defects, and the neural network reconstruction and neurological function recovery were enhanced in rodent ICH models through the mechanisms of neurogenesis, angiogenesis, anti-inflammation, and anti-apoptosis. However, many key issues associated with the survival, differentiation, and safety of grafted MSCs after ICH remain to be resolved, which hinder the clinical translation of MSC therapy. Herein, we reviewed an overview of the research status of MSC transplantation after ICH in different species including rodents, swine, monkey, and human, and the challenges for MSC-mediated ICH recovery from pathological microenvironment have been summarized. Furthermore, some efficient strategies for the outcome improvement of MSC transplantation were proposed.

PIEZO1 might be involved in cerebral ischemia-reperfusion injury through ferroptosis regulation: a hypothesis

Stroke is associated with high mortality and extremely high disability rate. Regulating ferroptosis seems to be a promising way to treat ischemic stroke. After stroke, vasogenic edema exerts a mechanical force on surrounding structures, which could activate the mechanosensitive PIEZO1 channel. Our previous research has found that brain cortex PIEZO1 expression was increased in the rat model of middle cerebral artery occlusion (MCAO), and PIEZO1 regulated oxygen-glucose deprivation/reoxygenation (OGD/R) injury in neurons through the calcium signaling. Considering recent studies has identified HIF1α as an essential protein in PIEZO1/calcium signaling, ferroptosis regulation and cerebral ischemia, we herein hypothesize that PIEZO1 might be involved in cerebral ischemia-reperfusion injury through ferroptosis regulation.

Aligned Biofunctional Electrospun PLGA-LysoGM1 Scaffold for Traumatic Brain Injury Repair

Due to poor regenerative capabilities of the brain, a treatment for traumatic brain injury (TBI) presents a serious challenge to modern medicine. Biofunctional scaffolds that can support neuronal growth, guide neurite elongation, and re-establish impaired brain tissues are urgently needed. To this end, we developed an aligned biofunctional scaffold (aPLGA-LysoGM1), in which poly (lactic-co-glycolic acid) (PLGA) was functionalized with sphingolipid ceramide N-deacylase (SCDase)-hydrolyzed monosialotetrahexosylganglioside (LysoGM1) and electrospinning was used to form an aligned fibrous network. As a ganglioside of neuronal membranes, the functionalized LysoGM1 endows the scaffold with unique biological properties favoring the growth of neuron and regeneration of injured brain tissues. Moreover, we found that the aligned PLGA-LysoGM1 fibers acted as a topographical cue to guide neurite extension, which is critical for organizing the formation of synaptic networks (neural networks). Systematic in vitro studies demonstrated that the aligned biofunctional scaffold promotes neuronal viability, neurite outgrowth, and synapse formation and also protects neurons from pressure-related injury. Additionally, in a rat TBI model, we demonstrated that the implantation of aPLGA-LysoGM1 scaffold supported recovery from brain injury, as more endogenous neurons were found to migrate and infiltrate into the defect zone compared with alternative scaffold. These results suggest that the aligned biofunctional aPLGA-LysoGM1 scaffold represents a promising therapeutic strategy for brain tissue regeneration following TBI.

Establishment of an Experimental Intracerebral Haemorrhage Model for Mass Effect Research using a Thermo-sensitive Hydrogel

The mechanical response of brain tissue closely relates to cerebral blood flow and brain diseases. During intracerebral haemorrhage (ICH), a mass effect occurs during the initial bleeding and results in significant tissue deformation. However, fewer studies have focused on the brain damage mechanisms and treatment approaches associated with mass effects compared to the secondary brain injuries after ICH, which may be a result of the absence of acceptable animal models mimicking a mass effect. Thus, a thermo-sensitive poly (N-isopropylacrylamide) (PNIPAM) hydrogel was synthesized and injected into the rat brain to establish an ICH model for mass effect research. The PNIPAM hydrogel or autologous blood was injected to establish an ICH animal model, and the space-occupying volumes, brain tissue elasticity, brain oedema, neuronal cell death, iron deposition and behavioural recovery were evaluated. The lower critical solution temperature of PNIPAM hydrogel was 32 °C, and the PNIPAM hydrogel had a rough surface with similar topography and pore structure to a blood clot. Furthermore, the ICH model animals who received an injection of PNIPAM and blood produced similar lesion volumes, elasticity changes and mechanically activated ion channel piezo-2 upregulation in brain tissue. Meanwhile, slight iron deposition, neuronal cell death and brain oedema were observed in the PNIPAM hydrogel model compared to the blood model. In addition, the PNIPAM hydrogel showed good biocompatibility and stability in vivo via subcutaneous implantation. Our findings show that PNIPAM hydrogel cerebral infusion can form a mass effect similar to haematoma and minimize the interference of blood, and the establishment of a mass effect ICH model is beneficial for understanding the mechanism of primary brain injury and the role of mass effects in secondary brain damage after ICH.

Lithium chloride promoted hematoma resolution after intracerebral hemorrhage through GSK-3β-mediated pathways-dependent microglia phagocytosis and M2-phenotype differentiation, angiogenesis and neurogenesis in a rat model

Some neuroprotective agents have been used clinically to address the resulting various adverse effects after intracerebral hemorrhage (ICH). Particularly, effectively removing the hematoma is of practical significance to exert neuroprotective effects following ICH. However, such agents are still in need of development. Lithium chloride (LiCl) has shown neuroprotective effects through glycogen synthase kinase-3β (GSK-3β) inhibition in a variety of central nervous system diseases. However, the impact of LiCl on hematoma clearance and the potential molecular mechanisms have not been reported. We hypothesize that LiCl may exert neuroprotective roles after ICH, partly through promoting hematoma resolution. In this study, male Sprague-Dawley rats were subjected to ICH followed by intraperitoneal injection of LiCl (60 mg/kg). The hematoma volumes of ipsilateral hemisphere were determined using Drabkin's method. The sensorimotor deficits were evaluated by neurobehavioral tests. The expressions of target molecules involved in the process of hematoma clearance were assayed using immunofluorescence and Western blot. Our results showed that animals treated with LiCl presented significantly reduced hematoma volume after ICH, which was coupled with enhanced microglia phagocytosis and its differentiation into M2-phenotype within the first 7 days and up-regulated angiogenesis and neurogenesis in the next 7 days. Meanwhile, GSK-3β was inhibited by LiCl and β-catenin became stabilized, which was followed by up-regulation of nuclear factor erythroid 2-related factor 2 and CD36 from days 3 to 7, and increase of vascular endothelial growth factor and brain-derived neurotrophic factor from days 7 to 14. These data suggest that LiCl promotes hematoma resolution via enhancing microglia phagocytosis and M2-phenotype differentiation in the early stage (< 7 days) and angiogenesis and neurogenesis in the chronic phase (days 7-14), thus eventually improving the functional outcomes of ICH rats.

Regulation of Cell Behavior by Hydrostatic Pressure

Hydrostatic pressure (HP) regulates diverse cell behaviors including differentiation, migration, apoptosis, and proliferation. Abnormal HP is associated with pathologies including glaucoma and hypertensive fibrotic remodeling. In this review, recent advances in quantifying and predicting how cells respond to HP across several tissue systems are presented, including tissues of the brain, eye, vasculature and bladder, as well as articular cartilage. Finally, some promising directions on the study of cell behaviors regulated by HP are proposed.

An enhanced charge-driven intranasal delivery of nicardipine attenuates brain injury after intracerebral hemorrhage

Intranasal drug delivery provided an alternative and effective approach for the intervention of an intracerebral hemorrhage (ICH). However, the short retention time at the absorption site and slow drug transport in intranasal gel influence the drug bioavailability and outcome of ICH. Herein, we fabricated a novel intranasal gel with oriented drug migration utilizing a charge-driven strategy to attenuate brain injury after ICH. Nicardipine hydrochloride (NCD) was entrapped in chitosan nanoparticles (CS NPs) and dispersed in an HAMC gel. Subsequently, one side of the gel was coated with a positively charged film. The oriented migration of CS NPs in the HAMC gel was determined, and the drug bioavailability was also enhanced. Furthermore, a blood-induced ICH rat model was established to evaluate the therapeutic effect of CS NPs + HAMC composites. Intranasal administration of the CS NPs + HAMC (+) composite showed a stronger neuroprotective effect in terms of brain edema reduction and neural apoptosis inhibition compared to the CS NPs + HAMC composite. These results suggested that the oriented and rapid drug transport from nose to brain can be achieved using the charge-driven strategy, and this intranasal drug delivery system has the potential to provide a new therapeutic strategy for the treatment of ICH.