Rat Model Of Cerebral Artery Occlusion Research Articles

Dynamic susceptibility contrast-enhanced MRI with USPIO in evaluating angiogenesis of the peri-infarction zones in subacute ischemic stroke in a permanent middle cerebral artery occlusion rat model.

Dynamic susceptibility contrast-enhanced magnetic resonance imaging (DSC-MRI) can reflect the angiogenesis of ischemic stroke. To investigate the value of DSC-MRI with ultrasmall superparamagnetic particles of iron oxides (USPIO) in evaluating angiogenesis in the peri-infarction zones in subacute ischemic stroke in a permanent middle cerebral artery occlusion (pMCAO) rat model. A total of 21 Sprague-Dawley rats were randomly divided into the pMCAO and sham operation groups. Every rat in each group underwent DSC-MRI with USPIO at 3, 5, and 7 days. DSC-MRI parameters of the relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), relative mean transit time (rMTT), and relative time to peak (rTTP) were measured, calculated, and compared among the different times. Sequential correlations were analyzed among the histopathological indexes with the microvascular density (MVD) and percentage of vascular area (%VA), the serum factors with vascular endothelial growth factor (VEGF), vascular cell adhesion molecule 1 (VCAM-1), and perfusion parameters, respectively. The rCBV and rCBF in the peri-infarction area of pMCAO rats were significantly higher on day 7 than on day 3, whereas no significant changes in rMTT and rTTP were observed at 3, 5, and 7 days. Significantly positive correlations were found between rCBV and MVD, %VA, VEGF, VCAM-1, between rCBF and MVD, %VA, VEGF, and VCAM-1 at 3, 5, and 7 days in the pMCAO group. The rCBV and rCBF deriving from USPIO-DSC may be potentially useful for evaluating the angiogenesis of the peri-infarction zones in the subacute phase of ischemic stroke.

METTL3 mediates m6A modification of lncRNA CRNDE to promote ATG10 expression and improve brain ischemia/reperfusion injury through YTHDC1

BackgroundIschemia/reperfusion (I/R) injury is a severe brain disorder with currently limited effective treatments. This study aims to explore the role of N6-methyladenosine (m6A) modification and associated regulatory factors in I/R to identify potential therapeutic targets.MethodsWe utilized a middle cerebral artery occlusion (MCAO) rat model and SH-SY5Y cells subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to assess m6A levels and investigate the impact of METTL3 overexpression on long non-coding RNA (lncRNA) CRNDE expression. The effects of silencing lncRNA CRNDE on the interaction between YTHDC1 and ATG10 mRNA, as well as the stability of ATG10 mRNA, were evaluated. Additionally, apoptosis rates, pro-inflammatory and anti-inflammatory factor levels, ATG10 expression, and autophagic activity were analyzed to determine the effects of METTL3. The reverse effects of YTHDC1 overexpression were also examined.ResultsMCAO rats and OGD/R-treated SH-SY5Y cells exhibited reduced m6A levels. METTL3 overexpression significantly inhibited lncRNA CRNDE expression. Silencing lncRNA CRNDE mitigated OGD/R-induced apoptosis and inflammation in SH-SY5Y cells, while enhancing autophagy and stabilizing ATG10 mRNA. METTL3 overexpression decreased cell apoptosis, reduced the levels of pro-inflammatory cytokines TNF-α, IL-1β, IL-6, and increased IL-10 secretion. Furthermore, METTL3 overexpression upregulated ATG10 expression and promoted autophagy. Conversely, lncRNA CRNDE overexpression negated these effects.ConclusionThe inhibition of lncRNA CRNDE affects the interaction between YTHDC1 and ATG10 mRNA and stabilizes ATG10 mRNA, mediated by METTL3 overexpression. These findings suggest that targeting lncRNA CRNDE to reduce apoptosis, inhibit inflammation, increase ATG10 expression, and enhance autophagy could offer new therapeutic strategies for I/R injury.

Tetrahydroxy Stilbene Glucoside Promotes Mitophagy and Ameliorates Neuronal Injury after Cerebral Ischemia Reperfusion via Promoting USP10-Mediated YBX1 Stability.

Tetrahydroxy stilbene glucoside (TSG) from Polygonum multiflorum exerts neuroprotective effects after ischemic stroke. We explored whether TSG improved ischemic stroke injury via PTEN-induced kinase 1 (PINK1)/Parkin-mediated mitophagy. Oxygen glucose deprivation/reoxygenation (OGD/R) in vitro model and middle cerebral artery occlusion (MCAO) rat model were established. Cerebral injury was assessed by neurological score, hematoxylin and eosin staining, 2,3,5-triphenyltetrazolium chloride staining, and brain water content. Apoptosis, cell viability, and mitochondrial membrane potential were assessed by flow cytometry, cell counting kit-8, and JC-1 staining, respectively. Colocalization of LC3-labeled autophagosomes with lysosome-associated membrane glycoprotein 2-labeled lysosomes or translocase of outer mitochondrial membrane 20-labeled mitochondria was observed with fluorescence microscopy. The ubiquitination level was determined using ubiquitination assay. The interaction between molecules was validated by coimmunoprecipitation and glutathione S-transferase pull-down. We found that TSG promoted mitophagy and improved cerebral ischemia/reperfusion damage in MCAO rats. In OGD/R-subjected neurons, TSG promoted mitophagy, repressed neuronal apoptosis, upregulated Y-box binding protein-1 (YBX1), and activated PINK1/Parkin signaling. TSG upregulated ubiquitin-specific peptidase 10 (USP10) to elevate YBX1 protein. Furthermore, USP10 inhibited ubiquitination-dependent YBX1 degradation. USP10 overexpression activated PINK1/Parkin signaling and promoted mitophagy, which were reversed by YBX1 knockdown. Moreover, TSG upregulated USP10 to promote mitophagy and inhibited neuronal apoptosis. Collectively, TSG facilitated PINK1/Parkin pathway-mediated mitophagy by upregulating USP10/YBX1 axis to ameliorate ischemic stroke.

Electroacupuncture pretreatment inhibits the TLR4/NF-κB/TXNIP/NLRP3 signaling pathway and modulates microglial polarization to alleviate cerebral ischemia-reperfusion injury in rats

Cerebral ischemia–reperfusion injury is frequently associated with neuroinflammation. The modulation of microglial polarization presents a promising approach for addressing cerebral ischemia–reperfusion injury. While electroacupuncture preconditioning has demonstrated efficacy in the management of ischemic stroke, the underlying therapeutic mechanisms remain inadequately understood. The investigation focused on elucidating the relationship between alterations in the TLR4/NF-κB/TXNIP/NLRP3 signaling pathway and microglial polarization subsequent to EA pretreatment. Established a middle cerebral artery occlusion (MCAO) rat model following electroacupuncture (EA) treatment at the Baihui (GV 20) acupoint. Male Sprague-Dawley rats were randomly assigned to the sham, Ischemia/Reperfusion (I/R), I/R + EA groups (n = 6). The results of Nissl Staining and TUNEL Stainingl showed that the number of curative neurons increased significantly after pretreatment, indicating an improvement in neuron formation and an increase in the number of austenite. The level of apoptosis in brain tissue in the I/R group was significantly higher than that in the sham operation group. Electroacupuncture pretreatment can effectively inhibit apoptosis occurrence. In addition, electric acupuncture pretreatment protects rat blood–brain barrier integrity and mitochondrial function. After treatment, the number of M1-type microglia decreased, while the number of M2-type microglia increased. These results suggest that EA preconditioning may alleviate neurological deficits and neuronal apoptosis caused by cerebral I/R injury, while maintaining the integrity of the blood–brain barrier and promoting microglial polarization through the TLR4/NF-κB/TXNIP/NLRP3 signaling pathway. Our findings establish a new molecular mechanism and theoretical foundation for electroacupuncture therapy of ischemic stroke.

Phillygenin attenuates cell apoptosis and microglia activation in cerebral ischaemia-reperfusion rats through activation of peroxisome proliferator-activated receptor γ.

Ischaemic stroke is a common condition that can lead to cerebral ischaemia-reperfusion injury. Phillygenin (PHI), a natural bioactive compound derived from Forsythia suspensa, has been shown to play a crucial role in regulating inflammation across various diseases. However, its specific regulatory effects in ischaemic stroke progression remain unclear. In this study, we established a middle cerebral artery occlusion (MCAO) rat model. Treatment with PHI (50 or 100 mg/kg) significantly reduced cerebral infarction in MCAO rats. PHI treatment also mitigated the increased inflammatory response observed in these rats. Additionally, PHI suppressed microglial activation by reducing iNOS expression, a marker of M1-type polarization of microglia, and attenuated increased brain tissue apoptosis in MCAO rats. Furthermore, PHI's anti-inflammatory effects in MCAO rats were abrogated upon co-administration with GW9662, a peroxisome proliferator-activated receptor γ (PPARγ) inhibitor. In summary, PHI attenuated microglial activation and apoptosis in cerebral ischaemia-reperfusion injury through PPARγ activation, suggesting its potential as a therapeutic agent for mitigating cerebral ischaemia-reperfusion injury.

Combining systems pharmacology, metabolomics, and transcriptomics to reveal the mechanism of Salvia miltiorrhiza-Cortex moutan herb pair for the treatment of ischemic stroke.

Ischemic stroke (IS), predominantly triggered by blockages in cerebral blood flow, is increasingly recognized as a critical public health issue. The combination of Salvia miltiorrhiza (SM) and Cortex moutan (CM), traditional herbs in Eastern medicine, are frequently used for managing heart and brain vascular conditions. However, the exact mechanisms by which this herb pair (SC) combats IS remain largely unexplored. This investigation focuses on pinpointing the active constituents in SC that contribute to its protective role and deciphering the mechanisms countering cerebral ischemia, particularly in a middle cerebral artery occlusion (MCAO) rat model. We employed UPLC-Q-TOF-MS/MS alongside network pharmacology for predicting SC's target actions against IS. Key ingredients were examined for their interaction with principal targets using molecular docking. The therapeutic impact was gauged through H&E, TUNEL, and Nissl staining, complemented by transcriptomic and metabolomic integration for mechanistic insights, with vital genes confirmed via western blot. UPLC-Q-TOF-MS/MS analysis revealed that the main components of SC included benzoylpaeoniflorin, salvianolic acid B, oxypaeoniflora, salvianolic acid A, and others. Network pharmacology analysis indicated that SC's mechanism in treating IS primarily involves inflammation, angiogenesis, and cell apoptosis-related pathways, potentially through targets such as AKT1, TNF, PTGS2, MMP9, PIK3CA, and VEGFA. Molecular docking underscored strong affinities between these constituents and their targets. Our empirical studies indicated SC's significant role in enhancing neuroprotection in IS, with transcriptomics suggesting the involvement of the VEGFA/PI3K/AKT pathway and metabolomics revealing improvements in various metabolic processes, including amino acids, glycerophospholipids, sphingomyelin, and fatty acids metabolisms.

Neuroprotection on ischemic brain injury by Mg2+/H2 released from endovascular Mg implant

Most acute ischemic stroke patients with large vessel occlusion require stent implantation for complete recanalization. Yet, due to ischemia-reperfusion injury, over half of these patients still experience poor prognoses. Thus, neuroprotective treatment is imperative to alleviate the ischemic brain injury, and a proof-of-concept study was conducted on “biodegradable neuroprotective stent”. This concept is premised on the hypothesis that locally released Mg2+/H2 from Mg metal within the bloodstream could offer synergistic neuroprotection against reperfusion injury in distant cerebral ischemic tissues. Initially, the study evaluated pure Mg's neuroactive potential using oxygen-glucose deprivation/reoxygenation (OGD/R) injured neuron cells. Subsequently, a pure Mg wire was implanted into the common carotid artery of the transient middle cerebral artery occlusion (MCAO) rat model to simulate human brain ischemia/reperfusion injury. In vitro analyses revealed that pure Mg extract aided mouse hippocampal neuronal cell (HT-22) in defending against OGD/R injury. Additionally, the protective effects of the Mg wire on behavioral abnormalities, neural injury, blood-brain barrier disruption, and cerebral blood flow reduction in MCAO rats were verified. Conclusively, Mg-based biodegradable neuroprotective implants could serve as an effective local Mg2+/H2 delivery system for treating distant cerebral ischemic diseases.

Electroacupuncture promotes angiogenesis by regulating miR-142-5p and activating ADAMTS1/PI3K/AKT pathway in ischemic stroke rats.

To observe the effect of electroacupuncture on miR-142-5p and ADAMTS1/PI3K/AKT pathway in rats with ischemic stroke, so as to explore the regulatory mechanism of electroacupuncture on angiogenesis after ischemic stroke. This study was divided into two parts. The first part of the experiment：SD rats were randomly divided into sham operation group, model group and electroacupuncture group. There were 20 rats in each group. The middle cerebral artery occlusion (MCAO) rat model was prepared using a modified Longa's method. In the electroacupuncture group, "Shuigou" (GV26) was selected for electroacupuncture intervention (4 Hz/20 Hz) for 30 min each time. The rats in the electroacupuncture group were given electroacupuncture immediately after successful modeling, once a day for 4 times. Hunter score and TTC staining were used to observe the neurological deficits and infarct volumes respectively；HE staining was used to observe the cortical pathological changes；immunohistochemistry was used to determine the changes of cerebral microvascular density. Real-time quantitative PCR and Western blot were used to observe the miR-142-5p expression, mRNA and protein expression levels of ADAMTS1, VEGF, PI3K, AKT, eNOS in ischemic cortex. The second part of the experiment：The rats were randomly divided into electroacupuncture+control group and electroacupuncture+miR-142-5p Antagomir group with 8 rats in each group. MCAO model was established after injection. Electroacupuncture+control group was given 0.9% sodium chloride solution injected into the right ventricle.The rats in the electroacupuncture+miR-142-5p Antagomir group were injected with miR-142-5p inhibitor into the right ventricle 30 min before modeling. Rats in electroacupuncture+control group and electroacupuncture+miR-142-5p Antagomir group were all given the same electroacupuncture treatment. Real-time fluorescence quantitative PCR was used to observe the effect of miR-142-5p Antagomir on the expression of miR-142-5p and ADAMTS1 mRNA. The effect of miR-142-5p Antagomir on ADAMTS1 protein was observed by Western blot. In the first part of the experiment, compared with the sham operation group, the Hunter score in the model group was significantly increased (P<0.01)；the volume of cerebral infarction in the model group was significantly increased (P<0.01)；the degree of brain edema and neuronal necrosis and the density of cerebral microvessels was increased；the cerebral microvascular density was significantly increased (P<0.01)；the expression levels of miR-142-5p and the mRNA expression levels of VEGF, AKT and eNOS were significantly decreased (P<0.01, P<0.05), and the protein expression levels of VEGF, p-AKT and eNOS were significantly down-regulated (P<0.01), while the mRNA expression levels of ADAMTS1 and PI3K, and the protein expression levels of ADAMTS1 and p-PI3K were all up-regulated (P<0.01, P<0.05) in the model group. Compared with the model group, after intervention, the Hunter score in the electroacupuncture group was decreased (P<0.01), the volume of cerebral infarction was significantly decreased (P<0.01)；the degree of brain edema and neuronal necrosis were alleviated；the cerebral microvascular density was significantly increased (P<0.01)；the expression of miR-142-5p and the mRNA expression of VEGF, PI3K, AKT and eNOS were increased (P<0.01), the protein expressions of VEGF, p-PI3K, p-AKT and eNOS were increased (P<0.01, P<0.05), while the mRNA and protein expression of ADAMTS1 were decreased (P<0.05, P<0.01). After injection of miR-142-5p inhibitor, compared with electroacupuncture+control group, the expression of miR-142-5p in electroacupuncture+miR-142-5p Antagomir group was decreased(P<0.05), while the mRNA and protein expression of ADAMTS1 were increased (P<0.01, P<0.05). Electroacupuncture at GV26 can improve the neurological damage of ischemic stroke rats, reduce the volume of cerebral infarction and promote angiogenesis. The mechanism may be associated with the function of electroacupuncture in promoting the expression of miR-142-5p, so as to inhibit the expression of its target gene ADAMTS1, mediate the up-regulation of VEGF expression, activate PI3K/AKT pathway, promote the release of eNOS, and participate in promoting angiogenesis in ischemic stroke rats.

Phosphorus Dendrimers Co-deliver Fibronectin and Edaravone for Combined Ischemic Stroke Treatment via Cooperative Modulation of Microglia/Neurons and Vascular Regeneration.

The development of new multi-target combination treatment strategies to tackle ischemic stroke (IS) remains to be challenging. Herein, a proof-of-concept demonstration of an advanced nanomedicine formulation composed of macrophage membrane (MM)-camouflaged phosphorous dendrimer (termed as AK137)/fibronectin (FN) nanocomplexes (NCs) loaded with antioxidant edaravone (EDV) to modulate both microglia and neurons for effective IS therapy is showcased. The created MM@AK137-FN/EDV (M@A-F/E) NCs with a mean size of 260nm possess good colloidal stability, sustained EDV release kinetics, and desired cytocompatibility. By virtue of MM decoration, the M@A-F/E NCs can cross blood-brain barrier, act on microglia to exert the anti-inflammatory (AK137 and FN) and antioxidative (FN and EDV) effects in vitro for oxidative stress alleviation, microglia M2 polarization, and reduction of pro-inflammatory cytokine secretion, and act on neuron cells to be anti-apoptotic. In a transient middle cerebral artery occlusion rat model, the developed M@A-F/E NCs can exert enhanced antioxidant/anti-inflammatory/anti-apoptotic therapeutic effects to comprehensively regulate the brain microenvironment and promote vascular regeneration to collaboratively restore the blood flow after ischemia-reperfusion. The designed MM-coated NCs composed of all-active ingredients of phosphorous dendrimers, FN, and EDV that can fully regulate the brain inflammatory microenvironment may expand their application scope in other neurodegenerative diseases.

A novel neuroprotective method against ischemic stroke by accelerating the drainage of brain interstitial fluid.

Ischemic stroke is a leading cause of death and disability worldwide. Inflammatory response after stroke determines the outcome of ischemic injury. A recent study has reported an efficient method, epidural arterial implantation (EAI), for accelerating interstitial fluid (ISF) drainage, which provides a promising strategy to clear pro-inflammatory cytokines in the brain extracellular space (ECS). In this study, the method of EAI was modified (m-EAI) to control its function of accelerating the ISF drainage at different time points following ischemic attack. The neuroprotective effect of m-EAI on ischemic stroke was evaluated with the transient middle cerebral artery occlusion (tMCAO) rat model. The results demonstrated the accumulation of IL-1β, IL-6, and TNF-α was significantly decreased by activating m-EAI at 7 d before and immediately after ischemic attack in tMCAO rats, accompanied with decreased infarct volume and improved neurological function. This study consolidates the hypothesis of exacerbated ischemic damage by inflammatory response and provides a new perspective to treat encephalopathy via brain ECS. Further research is essential to investigate whether m-EAI combined with neuroprotective drugs could enhance the therapeutic effect on ischemic stroke.

Hypomethylated leptin receptor reduces cerebral ischaemia-reperfusion injury by activating the JAK2/STAT3 signalling pathway.

To investigate the cerebroprotective effects of leptin in vitro and in vivo via the Janus kinase-2 (JAK2)/transcription factor signal transducer and activators of transcription-3 (STAT3) pathway and leptin receptors (LEPR). The study used the cellular oxygen-glucose deprivation (OGD) model in PC12 cells and the middle cerebral artery occlusion (MCAO) rat model of cerebral ischaemia-reperfusion injury (CIRI) to assess changes in gene expression and protein levels following leptin pretreatment. The methylated DNA immunoprecipitation (MeDIP) assay measured DNA methylation levels. The optimal leptin concentration for exerting neuroprotective effects against ischaemia-reperfusion injury in PC12 cells was 200 ng/ml in vitro, but excessive leptin diminished this effect. Leptin pretreatment in the MCAO rat model demonstrated a similar effect to previously reported leptin administration post-CIRI. In addition to regulating the expression of inflammation-related cytokines, Western blot analysis showed that leptin pretreatment upregulated BCL-2 and downregulated caspase 3 levels. The MeDIP analysis demonstrated that DNA methylation regulated LEPR gene expression in the MCAO rat model when leptin pretreatment was used. Exogenous leptin might bind to extra-activated LEPR by reducing the methylation level of the LEPR gene promoter region, which leads to an increase in phosphorylated JAK2/STAT3 and apoptotic signalling pathways.

Electroacupuncture ameliorates blood-brain barrier disruption after ischemic stroke through histone acetylation regulation at the matrix metalloproteinase 9 and tissue inhibitor of metalloproteinase 2 genes.

To explore whether the regulation of matrix metalloproteinase 9 (MMP-9)/ tissue inhibitors of MMPs (TIMPs) gene expression through histone acetylation is a possible mechanism by which electroacupuncture (EA) protects blood-brain barrier (BBB) integrity in a middle cerebral artery occlusion (MCAO) rat model. Male Sprague-Dawley rats were divided into four groups: the sham group, the MCAO group, the MCAO + EA (MEA) group, and the MCAO + EA + HAT inhibitor (HATi) group. The MCAO model was generated by blocking the middle cerebral artery. EA was applied to Baihui (GV20). Samples were collected 1 or 3 d after reperfusion. Neurological function scores and Evans blue extravasation were employed to evaluate the poststroke injury. The effect of EA on MMP-9/TIMPs gene expression was assessed by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) and chromatin immunoprecipitation (ChIP). Our results showed that EA treatment prominently improved neurological function and ameliorated BBB disruption. The RT-qPCR assay showed that EA reduced the expression of MMP-9 and promoted TIMP-2 mRNA expression, but HATi reversed these effects of EA. In addition, ChIP results revealed that EA decreased the enrichment of H3K9ace/H3K27ace at MMP-9 promoters and notably stimulated the recruitment of H3K9ace/H3K27ace at TIMP-2 promoter. EA treatment at Baihui (GV20) regulates the transcription of MMP-9 and TIMP-2 through histone acetylation modification in the acute stage of stroke, which preserves the structural integrity of the BBB in MCAO rats. These findings suggested that the histone acetylation-mediated transcriptional activity of target genes may be a crucial mechanism of EA treatment in stroke.

Electroacupuncture reduces corpus callosum injury in rats with permanent cerebral ischemia by inhibiting the activation of high-mobility group box 1 protein and the receptor for advanced glycation end products.

Previous studies have shown that cerebral ischemia can cause white matter injury in the brain. This study aimed to investigate the potential mechanism of electroacupuncture (EA) at the Baihui (GV20) and Zusanli (ST36) acupoints in protecting white matter. Sprague-Dawley rats were used to establish permanent middle cerebral artery occlusion (pMCAO) rat models. Comprehensive motor functions were assessed using the mesh experiment. Morphological changes in the myelin sheath were assessed with Luxol fast blue staining. Morphological changes in oligodendrocytes and myelinated axons were evaluated using Nissl staining. The expressions of high-mobility group box 1 protein (HMGB1) and the receptor for advanced glycation end products (RAGE) in the corpus callosum were detected by immunohistochemical staining and Western blot analysis. pMCAO caused severe injury to the corpus callosum, evidenced by significant loss of white matter fibers and myelinated axons, and induced overexpression of HMGB1 and RAGE in the corpus callosum. EA treatment significantly improved comprehensive motor function alleviated white matter damage, and downregulated the expression of HMGB1 and RAGE. Its effects were comparable to those of FPS-ZM1, a RAGE receptor inhibitor. In conclusion, EA effectively improves comprehensive motor function in rats with cerebral infarction and alleviates corpus callosum injury. This effect may be related to the inhibition of HMGB1 and RAGE overexpression.

ScRNAs reveals high-frequency rTMS-induced pericyte differentiation: Potential implications for vascular regeneration and blood-brain barrier stability in stroke

Stroke is a major cause of adult disability worldwide, often involving disruption of the blood-brain barrier (BBB). Repairing the BBB is crucial for stroke recovery, and pericytes, essential components of the BBB, are potential intervention targets. Repetitive transcranial magnetic stimulation (rTMS) has been proposed as a treatment for functional impairments after stroke, with potential effects on BBB integrity. However, the underlying mechanisms remain unclear. In this study using a transient middle cerebral artery occlusion (tMCAO) rat model, we investigated the impact of rTMS on post-stroke BBB. Through single-cell sequencing (ScRNAs), we observed developmental relationships among pericytes, endothelial cells, and vascular smooth muscle cells, suggesting the differentiation potential of pericytes. A distinct subcluster of pericytes emerged as a potential therapeutic target for stroke. Additionally, our results revealed enhanced cellular communication among these cell types, enriching signaling pathways such as IGF, TNF, NOTCH, and ICAM. Analysis of differentially expressed genes highlighted processes related to stress, differentiation, and development. Notably, rTMS intervention upregulated Reck in vascular smooth muscle cells, implicating its role in the classical Wnt signaling pathway. Overall, our bioinformatics findings suggest that rTMS may modulate BBB permeability and promote vascular regeneration following stroke. This might happen through 20 Hz rTMS promoting pericyte differentiation into vascular smooth muscle cells, upregulating Reck, then activating the classical Wnt signaling pathway, and facilitating vascular regeneration and BBB stability.

Buyang Huanwu Decoction suppresses ischemic stroke by suppressing glycolysis and cell apoptosis in rat brain microvascular endothelial cells

BackgroundBuyang Huanwu Decoction (BHD) is widely used in Chinese clinical practice for the treatment and prevention of ischemic cerebral vascular diseases. This study was designed to investigate the effects of BHD on ischemic stroke (IS) and its underlying mechanism. MethodsThe middle cerebral artery occlusion (MCAO) rat model and oxygen-glucose deprivation and reoxygenation (OGD/R) rat brain microvascular endothelial cell (RBMVEC) models were established. Brain infarction size and neurological score were calculated following MCAO surgery. Evans blue was used to measure blood brain barrier (BBB) permeability. Cell counting kit-8 (CCK-8) and TUNEL assays were performed to evaluate the cell viability and apoptosis of RBMVECs. Dual-luciferase reporter assay was used to analyze the transcriptional activities of apoptosis-related genes. ResultsResults showed that higher infarction volume, neurological scores, and BBB permeability in the MCAO group rats were reduced after BHD treatment. Drug serum (DS) treatment had no impact on the normal RBMVECs’ cell viability and cell apoptosis. Besides, DS treatment decreased the lactate production, glucose uptake, and extracellular acidification rate in normal and OGD/R-induced RBMVECs. DS treatment downregulated the protein levels of pan-lysine lactylation (kla), histone H3 lysine 18 lactylation (H3K18la), and the transcriptional of apoptotic protease activating factor-1 (Apaf-1) in OGD/R-treated RBMVECs. In addition, Apaf-1 overexpression decreased cell viability and increased apoptosis and glycolysis activity of OGD/R-treated RBMVECs. ConclusionIn summary, BHD inhibited glycolysis and apoptosis via suppressing the pan-kla and H3K18la protein levels and the Apaf-1 transcriptional activity, thus restraining the progression of IS.

A Minimalist Iron Oxide Nanoprobe for the High-Resolution Depiction of Stroke by Susceptibility-Weighted Imaging.

The precise mapping of collateral circulation and ischemic penumbra is crucial for diagnosing and treating acute ischemic stroke (AIS). Unfortunately, there exists a significant shortage of high-sensitivity and high-resolution in vivo imaging techniques to fulfill this requirement. Herein, a contrast enhanced susceptibility-weighted imaging (CE-SWI) using the minimalist dextran-modified Fe3O4 nanoparticles (Fe3O4@Dextran NPs) are introduced for the highly sensitive and high-resolution AIS depiction under 9.4 T for the first time. The Fe3O4@Dextran NPs are synthesized via a simple one-pot coprecipitation method using commercial reagents under room temperature. It shows merits of small size (hydrodynamic size 25.8nm), good solubility, high transverse relaxivity (r2) of 51.3 mM-1s-1 at 9.4 T, and superior biocompatibility. The Fe3O4@Dextran NPs-enhanced SWI can highlight the cerebral vessels readily with significantly improved contrast and ultrahigh resolution of 0.1mm under 9.4 T MR scanner, enabling the clear spatial identification of collateral circulation in the middle cerebral artery occlusion (MCAO) rat model. Furthermore, Fe3O4@Dextran NPs-enhanced SWI facilitates the precise depiction of ischemia core, collaterals, and ischemic penumbra post AIS through matching analysis with other multimodal MR sequences. The proposed Fe3O4@Dextran NPs-enhanced SWI offers a high-sensitivity and high-resolution imaging tool for individualized characterization and personally precise theranostics of stroke patients.

Luteolin-7-O-β-d-Glucuronide Attenuated Cerebral Ischemia/Reperfusion Injury: Involvement of the Blood-Brain Barrier.

Ischemic stroke is a common cerebrovascular disease with high mortality, high morbidity, and high disability. Cerebral ischemia/reperfusion injury seriously affects the quality of life of patients. Luteolin-7-O-β-d-glucuronide (LGU) is a major active flavonoid compound extracted from Ixeris sonchifolia (Bge.) Hance, a Chinese medicinal herb mainly used for the treatment of coronary heart disease, angina pectoris, cerebral infarction, etc. In the present study, the protective effect of LGU on cerebral ischemia/reperfusion injury was investigated in an oxygen-glucose deprivation/reoxygenation (OGD/R) neuronal model and a transient middle cerebral artery occlusion (tMCAO) rat model. In in vitro experiments, LGU was found to improve the OGD/R-induced decrease in neuronal viability effectively by the MTT assay. In in vivo experiments, neurological deficit scores, infarction volume rates, and brain water content rates were improved after a single intravenous administration of LGU. These findings suggest that LGU has significant protective effects on cerebral ischemia/reperfusion injury in vitro and in vivo. To further explore the potential mechanism of LGU on cerebral ischemia/reperfusion injury, we performed a series of tests. The results showed that a single administration of LGU decreased the content of EB and S100B and ameliorated the abnormal expression of tight junction proteins ZO-1 and occludin and metalloproteinase MMP-9 in the ischemic cerebral cortex of the tMCAO 24-h injury model. In addition, LGU also improved the tight junction structure between endothelial cells and the degree of basement membrane degradation and reduced the content of TNF-α and IL-1β in the brain tissue. Thereby, LGU attenuated cerebral ischemia/reperfusion injury by improving the permeability of the blood-brain barrier. The present study provides new insights into the therapeutic potential of LGU in cerebral ischemia.

Electro-scalp acupuncture regulates the expression of CYP27a1/b1, CYP24a and related inflammatory cytokines in ischemic cortex of rats with middle cerebral artery occlusion.

To observe the effect of electro-scalp acupuncture (ESA) on the expression of cytochrome P450a1/b1 (CYP27a1/b1), cytochrome P45024a (CYP24a), signal transducer and activator of transcription (STAT)4, STAT6, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-4 in ischemic cerebral cortex of rats with acute ischemic stroke, so as to explore its mechanism in alleviating inflammatory reaction of ischemic stroke. Sixty SD rats were randomly divided into sham-operation, model, vitamin D3 and ESA groups, with 15 rats in each group. The middle cerebral artery occlusion rat model was established with thread ligation according to Zea-Longa's method. Rats in the vitamin D3 group were given 1, 25-VitD3 solution (3 ng·100 g-1·d-1) by gavage, once daily for 7 days. Rats in the ESA group were treated at bilateral anterior parietotemporal slash (MS6) with ESA (2 Hz/100 Hz, 1 mA), 30 min a day for 7 days. Before and after interventions, the neurological deficit score and neurobehavioral score were evaluated. TTC staining was used to detect the volume of cerebral infarction in rats. The positive expressions of CYP24a, CYP27a1 and CYP27b1 in the cerebral cortex of ischemic area were detected by immunofluorescence. The mRNA expressions of STAT4 and STAT6 in the cerebral cortex of ischemic area were detected by quantitative real-time PCR. The protein expression levels of TNF-α, IL-1β and IL-4 in the cerebral cortex of ischemic area were detected by Western blot. Compared with the sham-operation group, the neurological deficit score, neurobehavioral score, the percentage of cerebral infarction volume, the positive expression level of CYP24a and mRNA expression level of STAT4, protein expression levels of TNF-α and IL-1β in cerebral cortex were increased (P<0.01), while the positive expression levels of CYP27a1/b1 and STAT6 mRNA, protein expression level of IL-4 were decreased (P<0.01) in the model group. After the treatment and compared with the model group, the neurological deficit score, neurobehavioral score, the percentage of cerebral infarction volume, the positive expression level of CYP24a and mRNA expression level of STAT4, protein expression levels of TNF-α and IL-1β in cerebral cortex were decreased (P<0.01), while the positive expression levels of CYP27a1/b1 and STAT6 mRNA expression level, protein expression level of IL-4 were increased (P<0.01) in the ESA and vitamin D3 groups. ESA can alleviate the inflammatory response in ischemic stroke, which maybe related to its function in regulating the balance between CYP27a1/b1 and CYP24a, converting vitamin D into active vitamin D3, inhibiting vitamin D3 degradation, and regulating Th1/Th2 balance.

MSC Promotes the Secretion of Exosomal lncRNA KLF3-AS1 to Regulate Sphk1 Through YY1-Musashi-1 Axis and Improve Cerebral Ischemia-Reperfusion Injury.

Stroke remains the 3rd leading cause of long-term disability globally. Over the past decade, mesenchymal stem cell (MSC) transplantation has been proven as an effective therapy for ischemic stroke. However, the mechanism of MSC-derived exosomal lncRNAs during cerebral ischemia/reperfusion (I/R) remains ambiguous. The oxygen-glucose deprivation/reoxygenation (OGD/R) and middle cerebral artery occlusion (MCAO) rat model were generated. MSCs were isolated and characterized by flow cytometry and histochemical staining, and MSC exosomes were purified and characterized by transmission electron microscopy, flow cytometry and Western blot. Western blot, RT-qPCR and ELISA assay were employed to examine the expression or secretion of key molecules. CCK-8 and TUNEL assays were used to assess cell viability and apoptosis. RNA immunoprecipitation and RNA pull-down were used to investigate the direct association between krüppel-like factor 3 antisense RNA 1 (KLF3-AS1) and musashi-1(MSI1). Yin Yang 1 (YY1)-mediated transcriptional regulation was assessed by chromatin immunoprecipitation and luciferase assays. The histological changes and immunoreactivity of key molecules in brain tissues were examined by H&E and immunohistochemistry. MSCs were successfully isolated and exhibited directionally differential potentials. MSC exosomal KLF3-AS1 alleviated OGD/R-induced inflammation in SK-N-SH and SH-SY5Y cells via modulating Sphk1. Mechanistical studies showed that MSI1 positively regulated KLF3-AS1 expression through its direct binding to KLF3-AS1. YY1 was identified as a transcription activator of MSI1 in MSCs. Functionally, YY1/MSI1 axis regulated the release of MSC exosomal KLF3-AS1 to modulate sphingosine kinase 1 (Sphk1)/NF-κB pathway, thereby ameliorating OGD/R- or cerebral I/R-induced injury. MSCs promote the release of exosomal KLF3-AS1 to regulate Sphk1 through YY1/MSI axis and improve cerebral I/R injury.

Mechanism of tetramethylpyrazine combined with neural stem cells transplantation on cerebral ischemia-reperfusion rats

This study aimed to investigate the intervention effect of tetramethylpyrazine(TMP) combined with transplantation of neural stem cells(NSCs) on middle cerebral artery occlusion(MCAO) rat model and to explore the mechanism of TMP combined with NSCs transplantation on ischemic stroke based on the regulation of stem cell biological behavior. MCAO rats were randomly divided into a model group, a TMP group, an NSCs transplantation group, and a TMP combined with NSCs transplantation group according to neurological function scores. A sham group was set up at the same time. The neurological function score was used to evaluate the improvement of neurological function in MCAO rats after TMP combined with NSCs transplantation. The proliferation, migration, and differentiation of NSCs were evaluated by BrdU, BrdU/DCX, BrdU/NeuN, and BrdU/GFAP immunofluorescence labeling. The protein expression of stromal cell-derived factor 1(SDF-1), C-X-C motif chemokine receptor 4(CXCR4), as well as oxidative stress pathway proteins nuclear factor erythroid 2-related factor 2(Nrf2), Kelch-like ECH-associated protein 1(KEAP1), heme oxygenase 1(HO-1), NAD(P)H quinone oxidoreductase 1(NQO1) was detected by Western blot to study the migration mechanism of TMP combined with NSCs. The results showed that TMP combined with NSCs transplantation significantly improved the neurological function score in MCAO rats. Immunofluorescence staining showed a significant increase in the number of BrdU~+, BrdU~+/DCX~+, BrdU~+/NeuN~+, and BrdU~+/GFAP~+ cells in the TMP, NSCs transplantation, and combined treatment groups, with the combined treatment group showing the most significant increase. Further Western blot analysis revealed significantly elevated expression of CXCR4 protein in the TMP, NSCs transplantation, and combined treatment groups, along with up-regulated protein expression of Nrf2, HO-1, and NQO1, and decreased KEAP1 protein expression. This study showed that both TMP and NSCs transplantation can promote the recovery of neurological function by promoting the proliferation, migration, and differentiation of NSCs, and the effect of TMP combined with NSCs transplantation is superior. The mechanism of action may be related to the activation of the Nrf2/HO-1/CXCR4 pathway.