miR-7-5p Affects Brain Edema After Intracerebral Hemorrhage and Its Possible Mechanism

MicroRNA Expression Profile in Acute Ischemic Stroke

Introduction

Acute ischemic stroke with large vessel occlusion (LVO) continues to present a considerable challenge to global health, marked by substantial morbidity and mortality rates. Although definitive diagnostic markers exist in the form of neuroimaging, their expense, limited availability, and potential for diagnostic delay can often result in missed opportunities for life-saving interventions. Despite several past attempts, research efforts to date have been fraught with challenges likely due to multiple factors such as inclusion of diverse stroke types, variable onset intervals, differing pathobiologies, and a range of infarct sizes, all contributing to inconsistent circulating biomarker levels. In this context, microRNAs (miRNAs) have emerged as a promising biomarker, demonstrating potential as biomarkers across various diseases, including cancer, cardiovascular conditions, and neurological disorders. These circulating miRNAs embody a wide spectrum of pathophysiological processes, encompassing cell death, inflammation, angiogenesis, neuroprotection, brain plasticity, and blood-brain barrier integrity. This pilot study explores the utility of circulating exosome-enriched extracellular vesicle (EV) miRNAs as potential biomarkers for anterior circulation LVO (acLVO) stroke.

Methods

In our longitudinal prospective cohort study, we collected data from acute large vessel occlusion (acLVO) stroke patients at four critical time intervals post-symptom onset: 0-6 hours, 6-12 hours, 12-24 hours, and 5-7 days. For comparative analysis, healthy individuals were included as control subjects. In this study, extracellular vesicles (EVs) were isolated from the plasma of participants, and the miRNAs within these EVs were profiled utilizing the NanoString nCounter system. Complementing this, a scoping review was conducted to examine the roles of specific miRNAs such as miR-140-5p, miR-210-3p, and miR-7-5p in acute ischemic stroke (AIS). This review involved a targeted PubMed search to assess their influence on crucial pathophysiological pathways in AIS, and their potential applications in diagnosis, treatment, and prognosis. The review also included an assessment of additional miRNAs linked to stroke.

Results

Within the first 6 hours of symptom onset, three specific miRNAs (miR-7-5p, miR-140-5p, and miR-210-3p) exhibited significant differential expression compared to other time points and healthy controls. These miRNAs have previously been associated with neuroprotection, cellular stress responses, and tissue damage, suggesting their potential as early markers of acute ischemic stroke.

Conclusion

This study highlights the potential of circulating miRNAs as blood-based biomarkers for hyperacute acLVO ischemic stroke. However, further validation in a larger, risk-matched cohort is required. Additionally, investigations are needed to assess the prognostic relevance of these miRNAs by linking their expression profiles with radiological and functional outcomes.

Association between circulating inflammatory biomarkers and functional outcome or perihaematomal oedema after ICH: a systematic review & meta-analysis

Background

Currently, there are no specific medical treatments for intracerebral haemorrhage (ICH), but the inflammatory response may provide a potential route to treatment. Given the known effects of acute brain injury on peripheral immunity, we hypothesised that inflammatory biomarkers in peripheral blood may be associated with clinical outcome following ICH, as well as perihaematomal oedema (PHO), which is an imaging marker of the neuroinflammatory response.

Methods

We searched OVID Medline and EMBASE on 07 April 2021 for studies of humans with ICH measuring an inflammatory biomarker in peripheral blood and PHO or clinical outcome. Risk of bias was assessed both by using a scale comprising features of the Newcastle-Ottawa Assessment Scale, STROBE-ME and REMARK guidelines, and for studies included in meta-analysis, also by the QUIPS tool.We used random effects meta-analysis to pool standardised mean differences (SMD) if ≥1 study quantified the association between identical biomarkers and measures of PHO or functional outcome.

Results

Of 8,615 publications, 16 examined associations between 21 inflammatory biomarkers and PHO (n=1,299 participants), and 93 studies examined associations between ≥1 biomarker and clinical outcome (n=17,702 participants). Overall, 20 studies of nine biomarkers (n=3,199) met criteria for meta-analysis of associations between inflammatory biomarkers and clinical outcome. Death or dependency (modified Rankin Scale (mRS) 3‒6) 90 days after ICH was associated with higher levels of fibrinogen (SMD 0.32; 95%CI [0.04, 0.61]; p=0.025), and high mobility group box protein 1 (HMGB1) (SMD 1.67; 95%CI [0.05, 3.30]; p=0.04). Higher WBC was associated with death or dependency at 90 days (pooled SMD 0.27; 95% CI [0.11, 0.44]; p=0.001; but the association was no longer significant when the analysis was restricted to studies with a low risk of bias (pooled SMD 0.22; 95% CI -0.04-0.48). Higher CRP seemed to be associated with death or dependency at 90 days (pooled SMD 0.80; 95% CI [0.44, 1.17]; p<0.0001) but this association was no longer significant when adjusted OR were pooled (OR 0.99 (95% CI 0.98-1.01)).

Conclusions

Higher circulating levels of, fibrinogen and HMGB1 are associated with poorer outcomes after ICH. This study highlights the clinical importance of the inflammatory response to ICH and identifies additional research needs in determining if these associations are mediated via PHO and are potential therapeutic targets.

Registration

PROSPERO ( CRD42019132628; 28/05/2019).

Glymphatic system: an emerging therapeutic approach for neurological disorders

The functions of the glymphatic system include clearance of the metabolic waste and modulation of the water transport in the brain, and it forms a brain-wide fluid network along with cerebrospinal fluid (CSF) and interstitial fluid (ISF). The glymphatic pathway consists of periarterial influx of CSF, astrocyte-mediated interchange between ISF and CSF supported by aquaporin-4 (AQP4) on the endfeet of astrocyte around the periarterioles, and perivenous efflux of CSF. Finally, CSF is absorbed by the arachnoid granules or flows into the cervical lymphatic vessels. There is growing evidence from animal experiments that the glymphatic system dysfunction is involved in many neurological disorders, such as Alzheimer's disease, stroke, epilepsy, traumatic brain injury and meningitis. In this review, we summarize the latest progress on the glymphatic system and its driving factors, as well as changes in the glymphatic pathway in different neurological diseases. We significantly highlight the likely therapeutic approaches for glymphatic pathway in neurological diseases, and the importance of AQP4 and normal sleep architecture in this process.

Effects of a neurokinin-1 receptor antagonist in the acute phase after thoracic spinal cord injury in a rat model

Objective

Disruption of the blood-spinal cord barrier (BSCB) with subsequent edema formation and further neuroinflammation contributes to aggravation of spinal cord injury (SCI). We aimed to observe the effect of antagonizing the binding of the neuropeptide Substance-P (SP) to its neurokinin-1 (NK1) receptor in a rodent SCI model.

Methods

Female Wistar rats were subjected to a T9 laminectomy with or without (Sham) a T9 clip-contusion/compression SCI, followed by the implantation of an osmotic pump for the continuous, seven-day-long infusion of a NK1 receptor antagonist (NRA) or saline (vehicle) into the intrathecal space. The animals were assessed via MRI, and behavioral tests were performed during the experiment. 7 days after SCI, wet & dry weight and immunohistological analyses were conducted.

Results

Substance-P inhibition via NRA showed limited effects on reducing edema. However, the invasion of T-lymphocytes and the number of apoptotic cells were significantly reduced with the NRA treatment. Moreover, a trend of reduced fibrinogen leakage, endothelial and microglial activation, CS-GAG deposition, and astrogliosis was found. Nevertheless, only insignificant general locomotion recovery could be observed in the BBB open field score and the Gridwalk test. In contrast, the CatWalk gait analysis showed an early onset of recovery in several parameters.

Conclusion

Intrathecal administration of NRA might reinforce the integrity of the BSCB in the acute phase after SCI, potentially attenuating aspects of neurogenic inflammation, reducing edema formation, and improving functional recovery.

Dl-3-n-butylphthalide improves intestinal microcirculation disorders in septic rats by regulating the PI3K/AKT signaling pathway and autophagy

PURPOSE

Sepsis has complex pathophysiological mechanisms that bring new challenges in the treatment of sepsis at a time when the intestinal microcirculation in sepsis is receiving increasing attention. Dl-3-n-butylphthalide (NBP), which is a drug that can improve multiorgan ischemic diseases, is also worth examining to improve the intestinal microcirculation in sepsis.

METHODS

In this study, male Sprague-Dawley rats were divided into the sham group (n = 6), CLP group (n = 6), NBP group (n = 6) and NBP + LY294002 group (n = 6). The rat model of severe sepsis was established by cecal ligation and puncture (CLP). Abdominal wall incisions and sutures were performed in the first group, and CLP was performed in the latter three groups. Normal saline/NBP/NBP + LY294002 solution was injected intraperitoneally 2 h or 1 h before modeling. Hemodynamic data (blood pressure and heart rate) were recorded at 0, 2, 4 and 6 h. Sidestream dark field (SDF) imaging and the Medsoft System were used to observe the intestinal microcirculation of rats and obtain data at 0, 2, 4, and 6 h. Six hours after the model was established, the serum levels of TNF-α and IL-6 were measured to evaluate the level of systemic inflammation. Pathological damage to the small intestine was evaluated by electron microscopy and histological analysis. The expression levels of P-PI3K, PI3K, P-AKT, AKT, LC3 and p62 in the small intestine were analyzed by Western blotting. The expressions of P-PI3K, P-AKT, LC3 and P62 in small intestine were detected by immunohistochemical staining.

RESULTS

NBP improved intestinal microcirculation disturbances in septic rats, alleviated the systemic inflammatory response, reduced the destruction of the small intestinal mucosa and the disruption of microvascular endothelial cells, and alleviated autophagy in vascular endothelial cells. NBP increased the ratio of P-PI3K/total PI3K, P-AKT/total AKT, and P62/β-actin and decreased the ratio of LC3 II/LC3 I.

CONCLUSION

NBP ameliorated intestinal microcirculation disturbances and the destruction of small intestinal vascular endothelial cells in septic rats by activating the PI3K/Akt signaling pathway and regulating autophagy.

CircBCL11B acts as a ceRNA to facilitate 1,2-dichloroethane-induced astrocyte swelling via miR-29b-3p/AQP4 axis in SVG p12 cells

1,2-Dichloroethane (1,2-DCE) is a pervasive environmental pollutant found in ambient and residential air, as well as ground and drinking water. Brain edema is the primary pathological consequence of 1,2-DCE overexposure. We found that microRNA (miRNA)-29b dysregulation after 1,2-DCE exposure can aggravate brain edema by suppressing aquaporin 4 (AQP4). Moreover, circular RNAs (circRNAs) can regulate the expression of downstream target genes through miRNA, and affect protein function. However, circRNAs' role in 1,2-DCE-induced brain edema via miR-29b-3p/AQP4 axis remains unclear. To address the mechanism's bottleneck, we explored the circRNA-miRNA-mRNA network underlying 1,2-DCE-driven astrocyte swelling in SVG p12 cells by circRNA sequencing, electron microscopy and isotope ³H labeling combined with the 3-O-methylglucose uptake method. The results showed that 25 and 50mM 1,2-DCE motivated astrocyte swelling, characterized by increased water content, enlarged cell vacuoles, and mitochondrial swelling. This was accompanied by miR-29b-3p downregulation and AQP4 upregulation. We verified that AQP4 were negatively regulated by miR-29b-3p in 1,2-DCE-induced astrocyte swelling. Also, circRNA sequencing highlighted that circBCL11B was upregulated by 1,2-DCE. This was manifested as circBCL11B overexpression playing an endogenous competitive role via upregulating AQP4 by binding to miR-29b-3p, thus leading to astrocyte swelling. Conversely, circBCL11B knockdown reversed the 1,2-DCE-motivated AQP4 upregulation and alleviated the cell swelling. Finally, we demonstrated that the circBCL11B was targeted to miR-29b-3p by fluorescence in situ hybridization and dual-luciferase reporter assay. In conclusion, our findings indicate that circBCL11B acts as a competing endogenous RNA to facilitate 1,2-DCE-caused astrocyte swelling via miR-29b-3p/AQP4 axis. These observations provide new insight into the epigenetic mechanisms underlying 1,2-DCE-induced brain edema.

The Role of Mitochondria-Targeting miRNAs in Intracerebral Hemorrhage

Non-traumatic intracerebral hemorrhage (ICH) is the most common type of hemorrhagic stroke, most often occurring between the ages of 45 and 60. Arterial hypertension (AH) is most often the cause of ICH, followed by atherosclerosis, blood diseases, inflammatory changes in cerebral vessels, intoxication and vitamin deficiencies. Cerebral hemorrhage can occur by diapedesis or as a result of a ruptured vessel. AH is difficult to treat, requires surgery and can lead to disability or death. One of the important directions in the study of the pathogenesis of ICH is mitochondrial dysfunction and its regulation. The key role of mitochondrial dysfunction in AH and atherosclerosis, as well as in the development of brain damage after hemorrhage, has been acknowledged. MicroRNAs (miRNAs) are a class of non-coding RNAs (about 18-22 nucleotides) that regulate a variety of biological processes including cell differentiation, proliferation, apoptosis, etc., primarily through gene repression. There is growing evidence to support dysregulated miRNAs in various cardiovascular diseases, including ICH. Further, the realization of miRNAs within mitochondrial compartment has challenged the traditional knowledge of signaling pathways involved in the regulatory network of cardiovascular diseases. However, the role of miRNAs in mitochondrial dysfunction for ICH is still under-appreciated, with comparatively much lesser studies and investigations reported, than those in other cardiovascular diseases. In this review, we summarize the up-to-date findings on the published role miRNAs in mitochondrial function for ICH, and the potential use of miRNAs in clinical settings, such as potential therapeutic targets and non-invasive diagnostic/prognostic biomarker tools.

MiR-7-5p attenuates vascular smooth muscle cell migration and intimal hyperplasia after vascular injury by NF-kB signaling

Background

Atherosclerosis (AS) is the primary cause of coronary artery disease, which is featured by aberrant proliferation, differentiation, and migration of vascular smooth muscle cells (VSMCs). MicroRNAs play crucial roles in AS, but the function of miR-7-5p in AS remains unclear. Here, we aimed to explore the effect of miR-7-5p on AS and VSMCs in vitro and in vivo.

Methods

The in vivo rat AS model and apoE-/- mouse model were established. The carotid artery injury was checked by immunohistochemistry staining. The RNA levels of miR-7-5p and p65 were measured by qPCR assay. Protein levels were checked by western blotting. Cell apoptosis was evaluated by flow cytometry. Cell migration was checked by Transwell assay and wound healing assay. The potential interaction between miR-7-5p with p65 was checked by luciferase reporter gene assay.

Results

MiR-7-5p was downregulated and NF-κB p65 was upregulated in injured carotid arteries in rat model. The carotid artery injury in the AS rats and the treatment of miR-7-5p attenuated the phenotype in the model. Immunohistochemistry staining and Western blot analysis revealed that PCNA levels were increased in injured carotid arteries of the model rats and miR-7-5p could reverse the levels. The cell viability of VSMCs was induced by PDGF-BB but miR-7-5p blocked the phenotype. PDGF-BB decreased apoptosis of VSMCs, while miR-7-5p was able to restore the cell apoptosis in the model. PDGF-BB-induced migration of VSMCs was attenuated by miR-7-5p. miR-7-5p mimic remarkably repressed the luciferase activity of p65 in VSMCs. The levels of p65 were inhibited by miR-7-5p in the cells. The PDGF-BB-promoted cell viability and migration of VSMCs was repressed by miR-7-5p and p65 overexpression reversed the phenotype.

Conclusion

We concluded that miR-7-5p attenuates vascular smooth muscle cell migration and intimal hyperplasia after vascular injury by NF-kB signaling.

Determination of brain water content by dry/wet weight measurement for the detection of experimental brain edema

Brain edema is a fatal pathological state in which brain volume increases as a result of abnormal accumulation of fluid within the brain parenchyma. A key attribute of experimentally induced brain edema - increased brain water content (BWC) - needs to be verified. Various methods are used for this purpose: specific gravimetric technique, electron microscopic examination, magnetic resonance imaging (MRI) and dry/wet weight measurement. In this study, the cohort of 40 rats was divided into one control group (CG) and four experimental groups with 8 rats in each group. The procedure for determining BWC using dry/wet weight measurement was initiated 24 h after the completion of edema induction by the water intoxication method (WI group); after the intraperitoneal administration of Methylprednisolone (MP) together with distilled water during edema induction (WI+MP group); 30 min after osmotic blood brain barrier disruption (BBBd group); after injection of MP via the internal carotid artery immediately after BBBd (BBBd + MP group). While induction of brain edema (WI, BBBd) resulted in significantly higher BWC, there was no increase in BWC in the MP groups (WI+MP, BBBd+MP), suggesting a neuroprotective effect of MP in the development of brain edema.

Synergic Effect of Phthalide Lactones and Fluconazole and Its New Analogues as a Factor Limiting the Use of Azole Drugs against Candidiasis

The resistance of Candida albicans and other pathogenic yeasts to azole antifungal drugs has increased rapidly in recent years and is a significant problem in clinical therapy. The current state of pharmacological knowledge precludes the withdrawal of azole drugs, as no other active substances have yet been developed that could effectively replace them. Therefore, one of the anti-yeast strategies may be therapies that can rely on the synergistic action of natural compounds and azoles, limiting the use of azole drugs against candidiasis. Synergy assays performed in vitro were used to assess drug interactions Fractional Inhibitory Concentration Index. The synergistic effect of fluconazole (1) and three synthetic lactones identical to those naturally occurring in celery plants-3-n-butylphthalide (2), 3-n-butylidenephthalide (3), 3-n-butyl-4,5,6,7-tetrahydrophthalide (4)-against Candida albicans ATCC 10231, C. albicans ATCC 2091, and C. guilliermondii KKP 3390 was compared with the performance of the individual compounds separately. MIC₉₀ (the amount of fungistatic substance (in µg/mL) inhibiting yeast growth by 90%) was determined as 5.96-6.25 µg/mL for fluconazole (1) and 92-150 µg/mL for lactones 2-4. With the simultaneous administration of fluconazole (1) and one of the lactones 2-4, it was found that they act synergistically, and to achieve the same effect it is sufficient to use 0.58-6.73 µg/mL fluconazole (1) and 1.26-20.18 µg/mL of lactones 2-4. As fluconazole and phthalide lactones show synergy, 11 new fluconazole analogues with lower toxicity and lower inhibitory activity for CYP2C19, CYP1A2, and CYP2C9, were designed after in silico testing. The lipophilicity was also analyzed. A three-carbon alcohol with two rings was preserved. In all compounds 5-15, the 1,2,4-triazole rings were replaced with 1,2,3-triazole or tetrazole rings. The hydroxyl group was free or esterified with phenylacetic acid or thiophene-2-carboxylic acid chlorides or with adipic acid. In structures 11 and 12 the hydroxyl group was replaced with the fragment -CH₂Cl or = CH₂. Additionally, the difluorophenyl ring was replaced with unsubstituted phenyl. The structures of the obtained compounds were determined by ¹H NMR, and ¹³C NMR spectroscopy. Molecular masses were established by GC-MS or elemental analysis. The MIC₅₀ and MIC₉₀ of all compounds 1-15 were determined against Candida albicans ATCC 10231, C. albicans ATCC 2091, AM 38/20, C. guilliermondii KKP 3390, and C. zeylanoides KKP 3528. The MIC₅₀ values for the newly prepared compounds ranged from 38.45 to 260.81 µg/mL. The 90% inhibitory dose was at least twice as high. Large differences in the effect of fluconazole analogues 5-15 on individual strains were observed. A synergistic effect on three strains-Candida albicans ATCC 10231, C. albicans ATCC 2091, C. guilliermondii KKP 339-was observed. Fractional inhibitory concentrations FIC₅₀ and FIC₉₀ were tested for the most active lactone, 3-n-butylphthalide, and seven fluconazole analogues. The strongest synergistic effect was observed for the strain C. albicans ATCC 10231, FIC 0.04-0.48. The growth inhibitory amount of azole is from 25 to 55 µg/mL and from 3.13 to 25.3 µg/mL for 3-n-butylphthalide. Based on biological research, the influence of the structure on the fungistatic activity and the synergistic effect were determined.

Effects of butyphthalide on microglia polarization after intracerebral hemorrhage and the underlying mechanisms

OBJECTIVES

Because intracerebral hemorrhage (ICH) has high morbidity, disability and mortality, it is significant to find new and effective treatments for ICH. This study aims to explore the effect of butyphthalide (NBP) on neuroinflammation secondary to ICH and microglia polarization.

METHODS

A total of 48 healthy male SD rats were randomly divided into 6 groups: a sham 24 h group, a sham 72 h group, an ICH 24 h group, an ICH 72 h group, an ICH+NBP 24 h group, and an ICH+NBP 72 h group (8 rats per group). After operation, the neurological deficiencies were assessed based on improved Garcia scores and corner test. The expressions of Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB), nuclear factor erythroid 2-related factor 2 (Nrf2), aquaporin-4 (AQP4), zonula occludens-1 (ZO-1), occludin, CD68, CD86, and CD206 were observed by Western blotting. Inflammatory cytokines were detected by ELISA. The immunofluorescence was to detect the polarization of microglia.

RESULTS

1) Compared with the sham groups, the expression of TLR4 (24 h: P<0.05; 72 h: P<0.01), NF-κB (both P<0.01) and Nrf2 (both P<0.01) in the perihematoma of the ICH group was increased, leading to microglia activation (P<0.01). The expressions of IL-6 (24 h: P<0.05; 72 h: P<0.01) and TNF-α (both P<0.01), the pro-inflammatory cytokines were up-regulated, and the expression of anti-inflammatory cytokine IL-4 was down-regulated (both P<0.01). Besides, the expression of AQP4 was enhanced (both P<0.01). The protein level of tightly connected proteins (including ZO-1, occludin) was decreased (all P<0.01). The neurological function of the rats in the ICH group was impaired in the 2 time points (both P<0.01). 2) Compared with the sham group at 24 h and 72 h after the intervention of NBP, the expressions of TLR4 (both P<0.05) and NF-κB (both P<0.01) were significantly declined, and the expression of Nrf2 was further enhanced (both P<0.05) in the perihematoma of the ICH+NBP group. Furthermore, the expression of M1 microglia marker was inhibited (P<0.05), and the polarization of microglia to the M2 phenotype was promoted (P<0.01). 3) In terms of inflammation after ICH, the IL-4 expression in the ICH+NBP group was increased compared with the ICH group (24 h: P<0.05; 72 h: P<0.01); the expression of IL-6 was decreased significantly in the ICH+NBP 72 h group (P<0.01); the level of AQP4 was declined significantly in the ICH+NBP 24 h group (P<0.05), there was a downward trend in the 72-hour intervention group but without significant statistical difference. 4) Compared with the ICH group, the ZO-1 protein levels were increased (24 h: P<0.05; 72 h: P<0.01), and the symptoms of nerve defect were improved eventually (both P<0.05) in the ICH+NBP groups.

CONCLUSIONS

After ICH, the TLR4/NF-κB pathway is activated. The M1 microglia is up-regulated along with the release of detrimental cytokines, while the anti-inflammatory cytokines are down-regulated. The expression of AQP4 is increased, the tight junction proteins from the blood-brain barrier (BBB) is damaged, and the neurological function of rats is impaired. On the contrary, NBP may regulate microglia polarization to M2 phenotype and play a role in the neuroprotective effect mediated via inhibiting TLR4/NF-κB and enhancing Nrf2 pathways, which relieves the neuroinflammation, inhibits the expression of AQP4, repairs BBB, and improves neurological functional defects.

miR-141-3p protects against blood-brain barrier disruption and brain injury after intracerebral hemorrhage by targeting ZEB2

MicroRNAs (miRNAs) participate in the diagnosis and treatment of intracerebral hemorrhage (ICH). miR-141-3p has been widely reported to regulate neurological disorders and cerebropathy. However, the specific role of miR-141-3p in ICH has not yet been revealed. The aim of this study was exploration of the biological functions and mechanism of miR-141-3p in ICH by establishing a collagenase-induced ICH mouse model. After ICH induction, miR-141-3p mimics or miR-NC were administered into the right striatum of the model mice followed by the performance of neurological tests. After euthanasia of the mice, the injury volume, brain water content, and injury to the blood-brain barrier (BBB) were evaluated. Evans blue (EB) was used to stain the brain slices, and EB extravasation was detected to evaluate the injury to BBB. miR-141-3p expression in perihematomal edema and hematoma areas after ICH was assessed by RT-qPCR. The levels of tight junction proteins in brain tissues and human brain microvascular endothelial cells (BMECs) were evaluated by western blotting. The FITC-dextran 20 method was used to assess BMEC permeability. The binding between miR-141-3p and zinc finger E-box-binding homeobox 2 (ZEB2) was verified with a luciferase reporter assay. In this study, miR-141-3p overexpression alleviated ICH-induced brain injury and protected BBB integrity in vivo. ZEB2 was a target gene of miR-141-3p. ZEB2 overexpression promoted BBB disruption, and miR-141-3p overexpression attenuated the promoting effect exerted by ZEB2. Overall, miR-141-3p protects against BBB disruption and attenuates brain injuries induced by ICH by targeting ZEB2.

Rapid and improved oral absorption of N-butylphthalide by sodium cholate-appended liposomes for efficient ischemic stroke therapy

As a multi-target drug to treat ischemic stroke, N-butylphthalide (NBP) is extremely water-insoluble and exhibits limited oral bioavailability, impeding its wide oral application. Effective treatment of ischemic stroke by NBP requires timely and efficient drug exposure, necessitating the development of new oral formulations. Herein, liposomes containing biosurfactant sodium cholate (CA-liposomes) were systemically investigated as an oral NBP delivery platform because of its high biocompatibility and great potential for clinical applications. The optimized liposomes have a uniform hydrodynamic size of 104.30 ± 1.60 nm and excellent encapsulation efficiency (93.91 ± 1.10%). Intriguingly, NBP-loaded CA-liposomes produced rapid drug release and the cumulative release was up to 88.09 ± 4.04% during 12 h while that for NBP group was only 6.79 ± 0.99%. Caco-2 cell monolayer assay demonstrated the superior cell uptake and transport efficiency of NBP-loaded CA-liposomes than free NBP, which was mediated by passive diffusion via transcellular and paracellular routes. After oral administration to rats, NBP-loaded CA-liposomes exhibited rapid and almost complete drug absorption, with a t_max of 0.70 ± 0.14 h and an absolute bioavailability of 92.65% while NBP suspension demonstrated relatively low bioavailability (21.7%). Meanwhile, NBP-loaded CA-liposomes produced 18.30-fold drug concentration in the brain at 5 min compared with NBP suspension, and the brain bioavailability increased by 2.48-fold. As expected, NBP-loaded CA-liposomes demonstrated significant therapeutic efficacy in a middle cerebral artery occlusion rat model. Our study provides new insights for engineering oral formulations of NBP with fast and sufficient drug exposure against ischemic stroke in the clinic.

The Glymphatic System: A Novel Therapeutic Target for Stroke Treatment

The glymphatic system (GS) is a novel defined brain-wide perivascular transit network between cerebrospinal fluid (CSF) and interstitial solutes that facilitates the clearance of brain metabolic wastes. The complicated network of the GS consists of the periarterial CSF influx pathway, astrocytes-mediated convective transport of fluid and solutes supported by AQP4 water channels, and perivenous efflux pathway. Recent researches indicate that the GS dysfunction is associated with various neurological disorders, including traumatic brain injury, hydrocephalus, epilepsy, migraine, and Alzheimer’s disease (AD). Meanwhile, the GS also plays a pivotal role in the pathophysiological process of stroke, including brain edema, blood–brain barrier (BBB) disruption, immune cell infiltration, neuroinflammation, and neuronal apoptosis. In this review, we illustrated the key anatomical structures of the GS, the relationship between the GS and the meningeal lymphatic system, the interaction between the GS and the BBB, and the crosstalk between astrocytes and other GS cellular components. In addition, we contributed to the current knowledge about the role of the GS in the pathology of stroke and the role of AQP4 in stroke. We further discussed the potential use of the GS in early risk assessment, diagnostics, prognostics, and therapeutics of stroke.

An Insight into the microRNAs Associated with Arteriovenous and Cavernous Malformations of the Brain

Background: Brain arteriovenous malformations (BAVMs) and cerebral cavernous malformations (CCMs) are rare developmental anomalies of the intracranial vasculature, with an irregular tendency to rupture, and as of yet incompletely deciphered pathophysiology. Because of their variety in location, morphology, and size, as well as unpredictable natural history, they represent a management challenge. MicroRNAs (miRNAs) are strands of non-coding RNA of around 20 nucleotides that are able to modulate the expression of target genes by binding completely or partially to their respective complementary sequences. Recent breakthroughs have been made on elucidating their contribution to BAVM and CCM occurrence, growth, and evolution; however, there are still countless gaps in our understanding of the mechanisms involved. Methods: We have searched the Medline (PubMed; PubMed Central) database for pertinent articles on miRNAs and their putative implications in BAVMs and CCMs. To this purpose, we employed various permutations of the terms and idioms: ‘arteriovenous malformation’, ‘AVM’, and ‘BAVM’, or ‘cavernous malformation’, ‘cavernoma’, and ‘cavernous angioma’ on the one hand; and ‘microRNA’, ‘miRNA’, and ‘miR’ on the other. Using cross-reference search; we then investigated additional articles concerning the individual miRNAs identified in other cerebral diseases. Results: Seven miRNAs were discovered to play a role in BAVMs, three of which were downregulated (miR-18a, miR-137, and miR-195*) and four upregulated (miR-7-5p, miR-199a-5p, miR-200b-3p, and let-7b-3p). Similarly, eight miRNAs were identified in CCM in humans and experimental animal models, two being upregulated (miR-27a and mmu-miR-3472a), and six downregulated (miR-125a, miR-361-5p, miR-370-3p, miR-181a-2-3p, miR-95-3p, and let-7b-3p). Conclusions: The following literature review endeavored to address the recent discoveries related to the various implications of miRNAs in the formation and growth of BAVMs and CCMs. Additionally, by presenting other cerebral pathologies correlated with these miRNAs, it aimed to emphasize the potential directions of upcoming research and biological therapies.

L-3-n-butylphthalide promotes restoration after an experimental animal model of intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is a devastating type of stroke with high morbidity and mortality, and the effective therapies for ICH remain to be explored. L-3-n-butylphthalide (NBP) is widely used in the treatment of ischemic stroke. However, few studies evaluated the therapeutic effects of NBP on ICH. Therefore, the present study aims to evaluate the effects of NBP on ICH and its potential mechanism. The rats were randomly divided into sham-operated group, saline-treated (ICH + saline) group, and NBP-treated (ICH + NBP) group. The ICH model of SD rats induced by IV collagenase was established. The modified Garcia JH score was used to detect the neurological deficit in rats. Western Blot and immunohistochemistry analysis was applied to test the levels of UBIAD1 and caspase-3 expressions in the perihematomal region. The rates of apoptotic cells were detected by TUNEL staining. The results showed that NBP up-regulated the expression of UBIAD1, reduced the apoptotic cells in the perihematomal region, and improved the neurological deficit. Taken together, our study added some new evidence to the application of NBP in ICH treatment.