Cerebral Ischemic Injury Research Articles

Kellerin alleviates cerebral ischemic injury by inhibiting ferroptosis via targeting Akt-mediated transcriptional activation of Nrf2

BackgroundIschemic stroke (IS) is characterized as a detrimental cerebrovascular disease with high mortality and disability. Ferroptosis is a novel mechanism involved in neuronal death. There is a close connection between IS and ferroptosis, and inhibiting ferroptosis may provide an effective strategy for treating IS. Our previous investigations have discovered that kellerin, the active compound of Ferula sinkiangensis K. M. Shen, possesses the capability to shield against cerebral ischemia injury. PurposeOur objective is to clarify the relationship between the neuroprotective properties of kellerin against IS and its ability to modulate ferroptosis, and investigate the underlying regulatory pathway. Study designWe investigated the impact and mechanism of kellerin in C57BL/6 mice underwent middle cerebral artery occlusion/reperfusion (MCAO/R) as well as SH-SY5Y cells exposed to oxygen-glucose deprivation/ re-oxygenation (OGD/R). MethodsThe roles of kellerin on neurological severity, cerebral infarction and edema were investigated in vivo. The regulatory impacts of kellerin on ferroptosis, mitochondrial damage and Akt/Nrf2 pathway were explored. Molecular docking combined with drug affinity responsive target stability assay (DARTS) and cellular thermal shift assay (CETSA) were performed to analyze the potential target proteins for kellerin. ResultsKellerin protected against IS and inhibited ferroptosis in vivo. Meanwhile, kellerin improved the neuronal damage caused by OGD/R and suppressed ferroptosis by inhibiting the production of mitochondrial ROS in vitro. Further we found that kellerin directly interacted with Akt and enhanced its phosphorylation, leading to the increase of Nrf2 nuclear translocation and its downstream antioxidant genes expression. Moreover, kellerin's inhibitory effect on ferroptosis and mitochondrial ROS release was eliminated by inhibiting Akt/Nrf2 pathway. ConclusionsOur study firstly demonstrates that the neuroprotective properties of kellerin against IS are related to suppressing ferroptosis through inhibiting the production of mitochondrial ROS, in which its modulation on Akt-mediated transcriptional activation of Nrf2 plays an important role. This finding shed light on the potential mechanism that kellerin exerts therapeutic effects in IS.

METTL3 Mediates Microglial Activation and Blood-Brain Barrier Permeability in Cerebral Ischemic Stroke by Regulating NLRP3 Inflammasomes Through m6A Methylation Modification.

Cerebral ischemic stroke (CIS) is the main cause of disability. METTL3 is implicated in CIS, and we explored its specific mechanism. Middle cerebral artery occlusion (MCAO) rat model and oxygen-glucose deprivation/reperfusion (OGD/R) HAPI cell model were established and treated with LV-METTL3 or DAA, oe-METTL3, miR-335-3p mimics, or DAA, to assess their effects on MCAO rat neurological and motor function, cerebral infarction area, brain water content, microglial activation, blood-brain barrier (BBB) permeability, and NLRP3 inflammasome activation. METTL3, pri-miR-335-3p, mature miR-335-3p, and miR-335-3p mRNA levels were assessed by RT-qPCR; M1/M2 microglial phenotype proportion and M1/M2 microglia ratio, inflammatory factor levels, and m6A modification were assessed. MCAO rats manifested cerebral ischemia injury. METTL3 was under-expressed in CIS. METTL3 overexpression inhibited microglial activation and M1 polarization and BBB permeability in MCAO rats and inhibited OGD/R-induced microglial activation and reduced M1 polarization. METTL3 regulated miR-335-3p expression and inhibited NLRP3 inflammasome activation. m6A methylation inhibition averted METTL3's effects on NLRP3 activation, thus promoting microglial activation in OGD/R-induced cells and METTL3's effects on BBB permeability in MCAO rats. Briefly, METTL3 regulated miR-335-3p expression through RNA m6A methylation and inhibited NLRP3 inflammasome activation, thus repressing microglial activation, BBB permeability, and protecting against CIS.

Retracted: Block Copolymer Nanomicelle-Encapsulated Curcumin Attenuates Cerebral Ischemia Injury and Affects Stem Cell Marker Expression by Inhibiting lncRNA GAS5.

[This retracts the article DOI: 10.1155/2023/9821500.].

Exploring Chinese herbal medicine for ischemic stroke: insights into microglia and signaling pathways.

Ischemic stroke is a prevalent clinical condition affecting the central nervous system, characterized by a high mortality and disability rate. Its incidence is progressively rising, particularly among younger individuals, posing a significant threat to human well-being. The activation and polarization of microglia, leading to pro-inflammatory and anti-inflammatory responses, are widely recognized as pivotal factors in the pathogenesis of cerebral ischemia and reperfusion injury. Traditional Chinese herbal medicines (TCHMs) boasts a rich historical background, notable efficacy, and minimal adverse effects. It exerts its effects by modulating microglia activation and polarization, suppressing inflammatory responses, and ameliorating nerve injury through the mediation of microglia and various associated pathways (such as NF-κB signaling pathway, Toll-like signaling pathway, Notch signaling pathway, AMPK signaling pathway, MAPK signaling pathway, among others). Consequently, this article focuses on microglia as a therapeutic target, reviewing relevant pathway of literature on TCHMs to mitigate neuroinflammation and mediate IS injury, while also exploring research on drug delivery of TCHMs. The ultimate goal is to provide new insights that can contribute to the clinical management of IS using TCHMs.

The Role of Stem Cells as Therapeutics for Ischaemic Stroke.

Stroke remains one of the leading causes of death and disability worldwide. Current reperfusion treatments for ischaemic stroke are limited due to their narrow therapeutic window in rescuing ischaemic penumbra. Stem cell therapy offers a promising alternative. As a regenerative medicine, stem cells offer a wider range of treatment strategies, including long-term intervention for chronic patients, through the reparation and replacement of injured cells via mechanisms of differentiation and proliferation. The purpose of this review is to evaluate the therapeutic role of stem cells for ischaemic stroke. This paper discusses the pathology during acute, subacute, and chronic phases of cerebral ischaemic injury, highlights the mechanisms involved in mesenchymal, endothelial, haematopoietic, and neural stem cell-mediated cerebrovascular regeneration, and evaluates the pre-clinical and clinical data concerning the safety and efficacy of stem cell-based treatments. The treatment of stroke patients with different types of stem cells appears to be safe and efficacious even at relatively higher concentrations irrespective of the route and timing of administration. The priming or pre-conditioning of cells prior to administration appears to help augment their therapeutic impact. However, larger patient cohorts and later-phase trials are required to consolidate these findings.

Impact on post-stroke injury: Co-administration of metformin and CoQ10 in cerebral ischemia injury

Developing effective therapeutics for stroke, extending beyond brain injury to overcome the post stroke complications is the need of hour. Post-stroke recovery is a primary research goal, necessitating treatments targeting multiple aspects of stroke pathology to enhance patient outcomes. Co-administration of therapies presents a promising approach to address post-stroke complications. Here, we assessed the combined effect of Metformin (MET) and Coenzyme Q10 (CoQ10) in mitigating post-stroke injury in rats. Rats underwent bilateral common carotid artery occlusion followed by reperfusion. They were divided into groups: Sham, IR (ischemic reperfusion), MET-treated, CoQ10-treated, and co-administered (MET+CoQ10). All treatments were given intramuscularly for 1–3 days post-stroke. Brain infarct size was significantly reduced in all treatment groups as compared to IR. Neurological score, % alteration, transfer latency, and discrimination ratio are ameliorated in all treatment groups. Coadministration shows a significant reduction in LPO as compared to IR and MET-treated animals. Glutathione and BBB integrity improved in all treated groups. Histology shows less pyknosis and vacuolization in treated rats’ hippocampus. MET and CoQ10 treatment for 3 days post-stroke exhibited neuroprotective effects and improved cognitive function. Co-administration demonstrated enhanced antioxidant defense compared to individual treatments, suggesting potential synergy in mitigating post-stroke complications.

Beta-caryophyllene in psychiatric and neurological diseases: Role of blood-brain barrier.

Beta-caryophyllene is an abundant terpene in cannabis, cinnamon, black pepper, cloves, and citrus fruit, delivering a striking, woody-spicy, like cloves and a sweet fruity aroma. Beta-caryophyllene is a Food and Drug Administration-approved food additive with Generally Recognized as Safestatus. Interestingly, several biologic activities have been described for beta-caryophyllene, including anti-inflammatory and analgesic effects, neuroprotection against cerebral ischemia and neuronal injury, protection of neurovascular unit against oxidative damage, glial activation and neuroinflammation and anticonvulsant effects. In this chapter, we intend to review the beneficial effects of beta-caryophyllene in the context of psychiatric and neurological diseases. Also, we will analyze the possibility that the blood-brain-barrier may be a central target underlying the beneficial actions of beta-caryophyllene.

Emergence of taurine as a therapeutic agent for neurological disorders.

Taurine is a sulfur-containing, semi-essential amino acid that occurs naturally in the body. It alternates between inflammation and oxidative stress-mediated injury in various disease models. As part of its limiting functions, taurine also modulates endoplasmic reticulum stress, Ca2+ homeostasis, and neuronal activity at the molecular level. Taurine effectively protects against a number of neurological disorders, including stroke, epilepsy, cerebral ischemia, memory dysfunction, and spinal cord injury. Although various therapies are available, effective management of these disorders remains a global challenge. Approximately 30 million people are affected worldwide. The design of taurine formation could lead to potential drugs/supplements for the health maintenance and treatment of central nervous system disorders. The general neuroprotective effects of taurine and the various possible underlying mechanisms are discussed in this review. This article is a good resource for understanding the general effects of taurine on various diseases. Given the strong evidence for the neuropharmacological efficacy of taurine in various experimental paradigms, it is concluded that this molecule should be considered and further investigated as a potential candidate for neurotherapeutics, with emphasis on mechanism and clinical studies to determine efficacy.

Eriocalyxin B alleviated ischemic cerebral injury by limiting microglia-mediated excessive neuroinflammation in mice.

Excessive neuroinflammation mediated by microglia has a detrimental effect on the progression of ischemic stroke. Eriocalyxin B (EriB) was found with a neuroprotective effect in mice with Parkinson's disease via the suppression of microglial overactivation. This study aimed to investigate the roles of EriB in permanent middle cerebral artery occlusion (pMCAO) mice. The pMCAO was induced in the internal carotid artery of the mice by the intraluminal filament method, and EriB (10 mg/kg) was administered immediately after surgery by intraperitoneal injection. The behavior score, 2,3,5-triphenyltetrazole chloride staining, Nissl staining, TUNEL, immunohistochemistry, immunofluorescence, PCR, ELISA, and immunoblotting revealed that EriB administration reduced brain infarct and neuron death and ameliorated neuroinflammation and microglia overactivation in pMCAO mice, manifested by alterations of TUNEL-positive cell numbers, ionized calcium binding adaptor molecule 1 (Iba-1)-positive cell numbers, and expression of tumor necrosis factor-α, interleukin 6, IL-1β, inducible nitric oxide synthase, and arginase 1. In addition, EriB suppressed ischemia-induced activation of nuclear factor kappa B (NF-κB) signaling in the brain penumbra, suggesting the involvement of NF-κB in EriB function. In conclusion, EriB exerted anti-inflammatory effects in ischemia stroke by regulating the NF-κB signaling pathway, and this may provide insights into the neuroprotective effect of EriB in the treatment of ischemic stroke.

Circ_0000115 Protects Against Cerebral Ischemia Injury by Suppressing Neuronal Apoptosis, Oxidative Stress and Inflammation by miR-1224-5p/Nos3 Axis In Vitro.

Cerebral ischemia is a severe neurological disability related to neuronal apoptosis and cellular stress response. Circular RNAs (circRNAs) are emerging regulators of cerebral ischemia. Herein, this study proposed to probe the action of circ_0000115 in cerebral ischemia injury. The mouse neuroblastoma cells N2a and HT22 underwent oxygen-glucose deprivation (OGD) were used as a model of in vitro cerebral ischemia. Levels of genes and proteins were detected by qRT-PCR and western blotting. Cell proliferation and apoptosis were determined by EdU assay and flow cytometry. Western blotting was used to detect the protein level of pro-inflammatory factors. The oxidative stress injury was evaluated by detecting reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) generation. Dual-luciferase reporter and RIP assays were used to confirm the target relationship between miR-1224-5p and circ_0000115 or nitric oxide synthase 3 (NOS3). OGD exposure decreased circ_0000115 and NOS3 expression, and increased miR-1224-5p in N2a and HT22 cells in a time-dependent manner. Circ_0000115 silencing attenuated OGD-induced apoptosis, oxidative stress and inflammation in N2a and HT22 cells. Mechanistically, circ_0000115 directly sponged miR-1224-5p, which targeted NOS3. Furthermore, rescue experiments showed that miR-1224-5p overexpression abolished the neuroprotective effect of circ_0000115 in N2a and HT22 cells under OGD treatment. Besides that, silencing of miR-1224-5p protected N2a and HT22 cells against OGD-evoked injury, which was counteracted by NOS3 knockdown. Circ_0000115 protects N2a and HT22 cells against OGD-evoked neuronal apoptosis, inflammation, and oxidative stress via the miR-1224-5p/NOS3 axis, providing an exciting view of the pathogenesis of cerebral ischemia.

TREM2-IGF1 Mediated Glucometabolic Enhancement Underlies Microglial Neuroprotective Properties During Ischemic Stroke.

Microglia, the major resident immune cells in the central nervous system, serve as the frontline soldiers against cerebral ischemic injuries, possibly along with metabolic alterations. However, signaling pathways involved in the regulation of microglial immunometabolism in ischemic stroke remain to be further elucidated. In this study, using single-nuclei RNA sequencing, a microglial subcluster up-regulated in ischemic brain tissues is identified, with high expression of Igf1 and Trem2, neuroprotective transcriptional signature and enhanced oxidative phosphorylation. Microglial depletion by PLX3397 exacerbates ischemic brain damage, which is reversed by repopulating the microglia with high Igf1 and Trem2 phenotype. Mechanistically, Igf1 serves as one of the major down-stream molecules of Trem2, and Trem2-Igf1 signaling axis regulates microglial functional and metabolic profiles, exerting neuroprotective effects on ischemic stroke. Overexpression of Igf1 and supplementation of cyclocreatine restore microglial glucometabolic levels and cellular functions even in the absence of Trem2. These findings suggest that Trem2-Igf1 signaling axis reprograms microglial immunometabolic profiles and shifts microglia toward a neuroprotective phenotype, which has promising therapeutic potential in treating ischemic stroke.

Development of a therapeutic monoclonal antibody against circulating adipocyte fatty acid binding protein to treat ischaemic stroke.

Adipocyte fatty acid-binding protein (A-FABP) exacerbates cerebral ischaemia injury by disrupting the blood-brain barrier (BBB) through inducing expression of MMP-9. Circulating A-FABP levels positively correlate with infarct size in stroke patients. We hypothesized that targeting circulating A-FABP by a neutralizing antibody would alleviate ischaemic stroke outcome. Monoclonal antibodies (mAbs) against A-FABP were generated using mouse hybridoma techniques. Binding affinities of a generated mAb named 6H2 towards various FABPs were determined using Biacore. Molecular docking studies were performed to characterize the 6H2-A-FABP complex structure and epitope. The therapeutic potential and safety of 6H2 were evaluated in mice with transient middle cerebral artery occlusion (MCAO) and healthy mice, respectively. Replenishment of recombinant A-FABP exaggerated the stroke outcome in A-FABP-deficient mice. 6H2 exhibited nanomolar to picomolar affinities to human and mouse A-FABP, respectively, with minimal cross-reactivities with heart and epidermal FABPs. 6H2 effectively neutralized JNK/c-Jun activation elicited by A-FABP and reduced MMP-9 production in macrophages. Molecular docking suggested that 6H2 interacts with the "lid" of the fatty acid binding pocket of A-FABP, thus likely hindering the binding of its substrates. In mice with transient MCAO, 6H2 significantly attenuated BBB disruption, cerebral oedema, infarction, neurological deficits, and decreased mortality associated with reduced cytokine and MMP-9 production. Chronic 6H2 treatment showed no obvious adverse effects in healthy mice. These results establish circulating A-FABP as a viable therapeutic target for ischaemic stroke, and provide a highly promising antibody drug candidate with high affinity and specificity.

Transcutaneous electrical acupoint stimulation attenuated neuroinflammation and oxidative stress by activating SIRT1-induced signaling pathway in MCAO/R rat models

BackgroundSilent information regulator 1 (SIRT1) plays a beneficial role in cerebral ischemic injury. Previous reports have demonstrated that transcutaneous electrical acupoint stimulation (TEAS) exerts a beneficial effect on ischemic stroke; however, whether SIRT1 participates in the underlying mechanism for the neuroprotective effects of TEAS against ischemic brain damage has not been confirmed. MethodsThe rat models of middle cerebral artery occlusion/reperfusion (MCAO/R) were utilized in the current experiment. After MCAO/R surgery, rats in TEAS, EC and EX group received TEAS intervention with or without the injection of EX527, the SIRT1 inhibitor. Neurological deficit scores, infarct volume, hematoxylin eosin (HE) staining and apoptotic cell number were measured. The results of RNA sequencing were analyzed to determine the differential expression changes of genes among sham, MCAO and TEAS groups, in order to investigate the possible pathological processes involved in cerebral ischemia and explore the protective mechanisms of TEAS. Moreover, oxidative stress markers including MDA, SOD, GSH and GSH-Px were measured with assay kits. The levels of the proinflammatory cytokines, such as IL-6, IL-1β and TNF-α, were detected by ELISA assay, and Iba-1 (the microglia marker protein) positive cells was measured by immunofluorescence (IF). Western blot and IF were utilized to examine the levels of key molecules in SIRT1/FOXO3a and SIRT1/BRCC3/NLRP3 signaling pathways. ResultsTEAS significantly decreased brain infarcted size and apoptotic neuronal number, and alleviated neurological deficit scores and morphological injury by activating SIRT1. The results of RNA-seq and bioinformatic analysis revealed that oxidative stress and inflammation were the key pathological mechanisms, and TEAS alleviated oxidative injury and inflammatory reactions following ischemic stroke. Then, further investigation indicated that TEAS notably attenuated neuronal apoptosis, neuroinflammation and oxidative stress damage in the hippocampus of rats with MCAO/R surgery. Moreover, TEAS intervention in the MCAO/R model significantly elevated the expressions of SIRT1, FOXO3a, CAT, BRCC3, NLRP3 in the hippocampus. Furthermore, EX527, as the inhibitor of SIRT1, obviously abolished the anti-oxidative stress and anti-neuroinflammatory roles of TEAS, as well as reversed the TEAS-mediated elevation of SIRT1, FOXO3a, CAT and reduction of BRCC3 and NLRP3 mediated by following MCAO/R surgery. ConclusionsIn summary, these findings clearly suggested that TEAS attenuated brain damage by suppressing apoptosis, oxidative stress and neuroinflammation through modulating SIRT1/FOXO3a and SIRT1/BRCC3/NLRP3 signaling pathways following ischemic stroke, which can be a promising treatment for stroke patients.

Quercetin attenuates cerebral ischemic injury by inhibiting ferroptosis via Nrf2/HO-1 signaling pathway

AimsIschemic stroke is a severe cerebrovascular disease in which neuronal death continually occurs through multiple forms, including apoptosis, autophagy, pyroptosis and ferroptosis. Quercetin (QRC), as a natural flavonoid compound, has been reported to have pharmacological effects on ischemic injury accompanied by unclear anti-ferroptotic mechanisms. This study is designed to investigate the therapeutic effects of QRC against ferroptosis in ischemic stroke. Materials and methodsIn vivo, the model of MCAO rats were used to assess the protective effect of QRC on cerebral ischemic. Additionally, we constructed oxidative stressed and ferroptotic cell models to explore the effects and mechanisms of QRC on ferroptosis. The related proteins were analysed by western blotting, immunohistochemical and immunofluorescence techniques. ResultsThe experiments demonstrated that QRC improves neurological deficits, infarct volume, and pathological features in MCAO rats, also increased the viability of HT-22 cells exposed to H2O2 and erastin. These results, including MDA, SOD, GSH, ROS levels and iron accumulation, indicated that QRC suppresses the generation of lipid peroxides and may involve in the regulatory of ferroptosis. Both in vitro and in vivo, QRC was found to inhibit ferroptosis by up-regulating GPX4 and FTH1, as well as down-regulating ACSL4. Furthermore, we observed that QRC enhances the nuclear translocation of Nrf2 and activates the downstream antioxidative proteins. Importantly, the effect of QRC on ferroptosis can be reversed by the Nrf2 inhibitor ML385. ConclusionsThis study provides evidence that QRC has a neuroprotective effect by inhibiting ferroptosis, demonstrating the therapeutic potential for cerebral ischemic stroke.

Protective effect of Tat fused HPCA protein on neuronal cell death caused by ischemic injury

BackgroundBain ischemia is a disease that occurs for various reasons, induces reactive oxygen species (ROS), and causes fatal damage to the nervous system. Protective effect of HPCA on ischemic injury has not been extensively studied despite its significance in regulating calcium homeostasis and promoting neuronal survival in CA1 region of the brain. ObjectiveWe investigate the role of HPCA in ischemic injury using a cell-permeable Tat peptide fused HPCA protein (Tat-HPCA). MethodsWestern blot analysis determined the penetration of Tat-HPCA into HT-22 cells and apoptotic signaling pathways. 5-CFDA, AM, DCF-DA, and TUNEL staining confirmed intracellular ROS production and DNA damage. The intracellular Ca2+ was measured in primary cultured neurons treated with H2O2. Protective effects were examined using immunohistochemistry and cognitive function tests by passive avoidance test and 8-arm radial maze test. ResultsTat-HPCA effectively penetrated into HT-22 cells and inhibited H2O2-induced apoptosis, oxidative stress, and DNA fragmentation. It also effectively inhibited phosphorylation of JNK and regulated the activation of Caspase, Bax, Bcl-2, and PARP, leading to inhibition of apoptosis. Moreover, Ca2+ concentration decreased in cells treated with Tat-HPCA in primary cultured neurons. In an animal model of ischemia, Tat-HPCA effectively penetrated the hippocampus, inhibited cell death, and regulated activities of astrocytes and microglia. Additionally, Cognitive function tests show that Tat-HPCA improves neurobehavioral outcomes after cerebral ischemic injury. ConclusionThese results suggest that Tat-HPCA might have potential as a therapeutic agent for treating oxidative stress-related diseases induced by ischemic injury, including ischemia.

Therapeutic Use of Palmitoylethanolamide as an Anti-Inflammatory and Immunomodulator

Palmitoylethanolamine (PEA) is an endocannabinoid-like compound first encountered within the lipid fractions of specific foods and has intrigued researchers since the 1950s due to its therapeutic effects. This survey aims to explore the therapeutic promise held by PEA as an anti-inflammatory and immunomodulatory agent. The therapeutic impact of PEA reverberates across diverse physiological systems, such as the central nervous system, gastrointestinal tract, vascular network, and the digestive and respiratory system. Additionally, it is effective in pain management and reducing inflammation and immune responses. These attributes have fostered collaborations targeting conditions such as Alzheimer’s disease, multiple sclerosis, cerebral ischemia, neuroinflammation, general inflammation, pain, coagulopathy, steatohepatitis, and acute lung injury. PEA operates both independently and in synergy with other compounds, like paracetamol, luteolin, and oxymetazoline. This efficacy stems from its interactions with pivotal targets, including PPARα, PPAR-δ, PPAR-γ, CB1, CB2, GPR55, and TRPV1. Additionally, PEA exerts a direct influence on the inflammatory cascade, orchestrating precise adjustments in immune responses. Numerous animal studies have elucidated the inherent potential of PEA. Nevertheless, the imperative of reinforcing clinical investigation is evident. This review notably underscores the pivotal necessity for methodologically rigorous clinical trials to definitively establish the translational efficacy of PEA in ameliorating diverse inflammatory pathologies within the human milieu.

Huatanmaitong tablet alleviate cerebral ischemic reperfusion injury with hyperlipidaemia in rats by regulating OATPs/VEGF axis.

Stroke is the top priority pathogenesis of disability and death globally, affecting people worldwide. The presence of high levels of lipids in the blood has been confirmed as a vital factor of ischemic stroke. We aim to examine the effectiveness of Huatanmaitong tablet in hyperlipidemia rats that have experienced an ischemic stroke. We created a rat model of middle cerebral artery occlusion (MCAO) with hyperlipidemia as a basis. Following 8 weeks of high-fat diet, the model rats underwent MCAO surgery. Subsequently, the rats were administered huatanmaitong tablets and lipitor tablets as treatments. Therefore there are five groups, CONTROL, MCAO, hyperlipidemia (HLP), Huatanmaitong tablet (HTMTT) and Lipitor (LIPITOR) groups respective ly. To assess the efficacy of the medication, the serum lipid levels of rats were measured both prior to and following administration. Hematoxylin eosin staining was used to observe the alterations in the brain and liver structures within each group. VEGF and OATPs related factors were detected in brain, liver by using immunohistochemistry, Western blotting, and Quantitative PCR. After the model was established successfully, the infarct volume and behavioral scores of the model group, hyperlipidemia group, Huatan Maitong tablet group and Lipitor group had statistical differences (P<0.05). Blood lipid levels of rats were measured before and after treatment, and it was found that Huatanmaitong tablets effectively reduced these levels. Hematoxylin and eosin staining of the brain and liver showed that huatanmaitong tablets maintained the microstructure stability. Western blotting and real-time PCR revealed that Huatanmaitong tablets improved the expression level of organic anion transport (OATP1B1, OATP2B1) in rat tissues with ischemic stroke, enhancing the transmembrane transport of exogenous substances and maintaining homeostatic balance. Additionally, it down-regulated the expression of VEGF in various organs such as the brain, and liver, demonstrating the ability of Huatanmaitong tablets to remove phlegm, blood stasis, and promote circulation by regulating serum lipid levels, organic anion transport peptide, and VEGF in rats. The behavioral score of ischemic stroke rats can be improved and the neurological impairment symptoms of rats can be alleviated by Huatanmaitong tablet through the regulation of OATPS/VEGF axis.

Isolation of a novel isoprenylated phenolic compound and neuroprotective evaluation of Dodonaea viscosa extract against cerebral ischaemia–reperfusion injury in rats

Dodonaea viscosa grows widely in Saudi Arabia, but studies evaluating its neuroprotective activity are lacking. Thus, this study aimed to isolate and identify the secondary metabolites and evaluate the neuroprotective effects of D. viscosa leaves. The isolation and identification of phytochemicals were performed using chromatographic and spectroscopic techniques. The neuroprotective potential of the extract was evaluated against focal cerebral ischaemia–reperfusion injury in rat model. Neurobehavioural deficits in the rats were evaluated, and their brains were harvested to measure infarct volume and oxidative biomarkers. Results revealed the presence of three compounds: a novel isoprenylated phenolic derivative that was elucidated as 4-hydroxy-3-(3ʹ-methyl-2ʹ-butenyl) phenyl 1-O-β-D-apiosyl-(1ʹʹʹ → 6ʹʹ)- β-D-glucopyranoside (named Viscomarfadol) and two known compounds (isorhamnetin-3-O-rutinoside and epicatechin (4–8) catechin). Pre-treatment of the rats with the extract improved neurological outcomes. It significantly reduced neurological deficits and infarct volume; significantly reduced lipid peroxidation, as evidenced by decreased malondialdehyde levels; and significantly elevated antioxidant (superoxide dismutase, catalase, and glutathione) activities. These results indicate that D. viscosa is a promising source of bioactive compounds that can improve neurological status, decrease infarct volume, and enhance antioxidant activities in rats with cerebral ischaemic injury. Thus, D. viscosa could be developed into an adjuvant therapy for ischaemic stroke and other oxidative stress-related neurodegenerative disorders. Further investigations are warranted to explore other bioactive compounds in D. viscosa and evaluate their potential neuroprotective activities.

Proprotein convertase subtilisin/kexin type 9 inhibitor ameliorates cerebral ischemia in mice by inhibiting inflammation

ObjectivesTo investigate the potential protective effects of evolocumab, a proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor, on ischemic stroke and its underlying mechanisms. Materials and methodsWe established a mouse model with distal middle cerebral artery occlusion. We evaluated the therapeutic effects through neurological function and infarct size, while the underlying mechanisms were elucidated using western blotting and real-time polymerase chain reaction. ResultsEvolocumab improved neurological recovery, reduced the infarct volume, suppressed the activation of Toll-like receptor (TLR) 4 and nuclear factor-kappa B (NF-κB), and attenuated the increased levels of IL-1β and TNF-α after cerebral ischemia. ConclusionEvolocumab protects against cerebral ischemic injury by inhibiting inflammation. Therefore, the TLR4/NF-кB pathway may represent a major mechanism in ischemic stroke.

PCSK9 inhibitor protects against ischemic cerebral injury by attenuating inflammation via the GPNMB/CD44 pathway

BackgroundIschemic stroke is the second leading cause of death worldwide, and neuroinflammation has been recognized as a critical player in its progression. Meanwhile, proprotein convertase subtilisin/kexin type 9 inhibitor (PCSK9i) has been demonstrated to inhibit inflammatory response. However, the effects of PCSK9i on ischemic stroke remain unclear and require further investigation. MethodsTemporary middle cerebral artery occlusion (tMCAO) was performed to establish animal models of ischemic stroke in C57BL/6 mice. The PCSK9i were administered subcutaneously after 2 h tMCAO. Neurological function and cerebral infarct volume were measured by mNSS and TTC staining, respectively. RNA-seq was performed to investigate the changes in mechanistic pathways. Western blotting and immunofluorescence were applied to detect expression of GPNMB, CD44, IL-6, and iNOS. ResultsTreatment with PCSK9i significantly improved neurological deficits and reduced the volume of cerebral infarction. PCSK9i suppressed neuroinflammation by activating the GPNMB/CD44 signaling pathway, further exerting their protective effects. ConclusionTaken together, treatment with PCSK9i is an effective way to prevent ischemic stroke-induced brain injury.