Chrysophanol accelerates astrocytic mitochondria transfer to neurons and attenuates the cerebral ischemia-reperfusion injury in rats.

Astrocytes transfer extracellular functional mitochondria into neurons to rescue injured neurons after a stroke. However, there are no reports on drugs that interfere with intercellular mitochondrial transfer. Chrysophanol (CHR) was an effective drug for the treatment of cerebral ischemia-reperfusion injury (CIRI) and was selected as the test drug. The oxygen-glucose deprivation/reoxygenation (OGD/R) cell model and the middle cerebral artery occlusion animal model were established to investigate the effect of CHR on CIRI. The result showed that astrocytes could act as mitochondrial donors to ameliorate neuronal injury. Additionally, the neuroprotective effect of astrocytes was enhanced by CHR, the CHR improved the neuronal mitochondrial function, decreased the neurological deficit score and infarction volume, recovered cell morphology in ischemic penumbra. The mitochondrial fluorescence probe labeling technique has shown that the protective effect of CHR is associated with accelerated astrocytic mitochondrial transfer to neurons. The intercellular mitochondrial transfer may be an important way to ameliorate ischemic brain injury and be used as a key target for drug treatment.

Geraniol attenuates oxygen-glucose deprivation/reoxygenation-induced ROS-dependent apoptosis and permeability of human brain microvascular endothelial cells by activating the Nrf-2/HO-1 pathway.

Blood-brain barrier breakdown and ROS overproduction are important events during the progression of ischemic stroke aggravating brain damage. Geraniol, a natural monoterpenoid, possesses anti-apoptotic, cytoprotective, anti-oxidant, and anti-inflammatory activities. Our study aimed to investigate the effect and underlying mechanisms of geraniol in oxygen-glucose deprivation/reoxygenation (OGD/R)-induced human brain microvascular endothelial cells (HBMECs). Apoptosis, caspase-3 activity, and cytotoxicity of HBMECs were evaluated using TUNEL, caspase-3 activity, and CCK-8 assays, respectively. The permeability of HBMECs was examined using FITC-dextran assay. Reactive oxygen species (ROS) production was measured using the fluorescent probe DCFH-DA. The protein levels of zonula occludens-1 (ZO-1), occludin, claudin-5, ß-catenin, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) were determined by western blotting. Geraniol showed no cytotoxicity in HBMECs. Geraniol and ROS scavenger N-acetylcysteine (NAC) both attenuated OGD/R-induced apoptosis and increase of caspase-3 activity and the permeability to FITC-dextran in HBMECs. Geraniol relieved OGD/R-induced ROS accumulation and decrease of expression of ZO-1, occludin, claudin-5, and ß-catenin in HBMECs. Furthermore, we found that geraniol activated Nrf2/HO-1 pathway to inhibit ROS in HBMECs. In conclusion, geraniol attenuated OGD/R-induced ROS-dependent apoptosis and permeability in HBMECs through activating the Nrf2/HO-1 pathway.

Aucubin provides protection against cerebral ischaemia-reperfusion injury by suppressing neuronal apoptosis, oxidative stress, and inflammation through the modulation of the AKT-GSK-3ß-Nrf2 signal cascade.

Aucubin (AU) is a naturally occurring iridoid glycoside known to possess a wide range of pharmacological properties and exhibit a notable protective effect against various pathological conditions. Studies have shown that AU has neuroprotective properties in different neurological diseases. However, its potential protective effects against cerebral ischemia-reperfusion (CIR) injury have not been thoroughly investigated. This study aimed to investigate the impact of AU on CIR injury and explore the underlying mechanism. Cultured neurons treated with AU showed a significant reduction in apoptosis, oxidative stress, and inflammation caused by oxygen-glucose deprivation and reoxygenation (OGD/R). In a rat model of CIR, treatment with AU resulted in a significant decrease in cerebral infarct size and neurological deficits. AU treatment also reversed the increased apoptosis, oxidative stress, and inflammation in the brains of CIR rats. Furthermore, AU was found to enhance the activation of nuclear factor-erythroid 2-related factor 2 (Nrf2), accompanied by increased phosphorylation of serine/threonine-protein kinase AKT and glycogen synthase kinase-3 beta (GSK-3ß). The activation of Nrf2 induced by AU was reversed when the AKT-GSK-3ß cascade was blocked. Additionally, the neuroprotective effect of AU was significantly reduced when Nrf2 was pharmacologically suppressed. In conclusion, these findings suggest that AU exerts a neuroprotective effect on CIR injury, and this effect is mediated by the activation of Nrf2 through the AKT-GSK-3ß axis. This work highlights the potential of AU as a drug candidate for the treatment of CIR injury.

Urine Proteomic Signatures of Mild Hypothermia Treatment in Cerebral Ischemia-Reperfusion Injury in Rats.

Mild hypothermia (MH) is an effective measure to alleviate cerebral ischemia-reperfusion (I/R) injury. However, the underlying biological mechanisms remain unclear. This study set out to investigate dynamic changes in urinary proteome due to MH in rats with cerebral I/R injury and explore the neuroprotective mechanisms of MH. A Pulsinelli's four-vessel occlusion (4-VO) rat model was used to mimic global cerebral I/R injury. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed to profile the urinary proteome of rats with/without MH (32 °C) treatment after I/R injury. Representative differentially expressed proteins (DEPs) associated with MH were validated by western blotting in hippocampus. A total of 597 urinary proteins were identified, among which 119 demonstrated significant changes associated with MH. Gene Ontology (GO) annotation of the DEPs revealed that MH significantly enriched in endopeptidase activity, inflammatory response, aging, response to oxidative stress and reactive oxygen species, blood coagulation, and cell adhesion. Notably, changes in 12 DEPs were significantly reversed by MH treatment. Among them, 8 differential urinary proteins were previously reported to be closely associated with brain disease, including NP, FZD1, B2M, EPCR, ATRN, MB, CA1and VPS4A. Two representative proteins (FZD1, B2M) were further validated by western blotting in the hippocampus and the results were shown to be consistent with urinary proteomic analysis. Overall, this study strengthens the idea that urinary proteome can sensitively reflect pathophysiological changes in the brain, and appears to be the first study to explore the neuroprotective effects of MH by urinary proteomic analysis. FZD1 and B2M may be involved in the most fundamental molecular biological mechanisms of MH neuroprotection.

Ferritinophagy and Ferroptosis in Cerebral Ischemia Reperfusion Injury.

Cerebral ischemia-reperfusion injury (CIRI) is the second leading cause of death worldwide, posing a huge risk to human life and health. Therefore, investigating the pathogenesis underlying CIRI and developing effective treatments are essential. Ferroptosis is an iron-dependent mode of cell death, which is caused by disorders in iron metabolism and lipid peroxidation. Previous studies demonstrated that ferroptosis is also a form of autophagic cell death, and nuclear receptor coactivator 4(NCOA4) mediated ferritinophagy was found to regulate ferroptosis by interfering with iron metabolism. Ferritinophagy and ferroptosis are important pathogenic mechanisms in CIRI. This review mainly summarizes the link and regulation between ferritinophagy and ferroptosis and further discusses their mechanisms in CIRI. In addition, the potential treatment methods targeting ferritinophagy and ferroptosis for CIRI are presented, providing new ideas for the prevention and treatment of clinical CIRI in the future.

TMEM79 Ameliorates Cerebral Ischemia/Reperfusion Injury Through Regulating Inflammation and Oxidative Stress via the Nrf2/NLRP3 Pathway.

BACKGROUND: Cerebral ischemia/reperfusion injury (CIRI) is still a complicated disease with high fatality rates worldwide. Transmembrane Protein 79 (TMEM79) regulates inflammation and oxidative stress in some other diseases. METHODS: CIRI mouse model was established using C57BL/6J mice through middle cerebral artery occlusion-reperfusion (MCAO/R), and BV2 cells were subjected to oxygen and glucose deprivation/reoxygenation (OGD/R) to simulate CIRI. Brain tissue or BV2 cells were transfected or injected with lentivirus-carried TMEM79 overexpression vector. The impact of TMEM79 on CIRI-triggered oxidative stress was ascertained by dihydroethidium (DHE) staining and examination of oxidative stress indicators. Regulation of TMEM79 in neuronal apoptosis and inflammation was determined using TUNEL staining and ELISA. RESULTS: TMEM79 overexpression mitigated neurological deficit induced by MCAO/R and decreased the extent of cerebral infarct. TMEM79 prevented neuronal death in brain tissue of MCAO/R mouse model and suppressed inflammatory response by reducing inflammatory cytokines levels. Moreover, TMEM79 significantly attenuated inflammation and oxidative stress caused by OGD/R in BV2 cells. TMEM79 facilitated the activation of Nrf2 and inhibited NLRP3 and caspase-1 expressions. Rescue experiments indicated that the Nrf2/NLRP3 signaling pathway mediated the mitigative effect of TMEM79 on CIRI in vivo and in vitro. CONCLUSION: Overall, TMEM79 was confirmed to attenuate CIRI via regulating the Nrf2/NLRP3 signaling pathway.

A deuterohemin peptide protects cerebral ischemia-reperfusion injury by preventing oxidative stress in vitro and in vivo.

Cerebral ischemia-reperfusion injury (CIRI) is a brain injury that usually occurs during thrombolytic therapy for acute ischemic stroke and impacts human health. Oxidative stress is one of the major causative factors of CIRI. DhHP-3 is a novel peroxidase-mimicking enzyme that exhibits robust reactive oxygen species (ROS) scavenging ability in vitro. Here, we established in vitro and in vivo models of cerebral ischemia-reperfusion to mechanistically investigate whether DhHP-3 can alleviate CIRI. DhHP-3 could reduce ROS, down-regulate apoptotic proteins, suppress p53 phosphorylation, attenuate the DNA damage response (DDR), and inhibit apoptosis in SH-SY5Y cells subjected to oxygen-glucose deprivation/re-oxygenation (OGD/R) and in the brain of Sprague Dawley rats subjected to transient middle cerebral artery occlusion. In conclusion, DhHP-3 has bioactivity of CIRI inhibition through suppression of the ROS-induced apoptosis.

The protective effect and mechanism of glycosides of cistanche deserticola on rats in middle cerebral artery occlusion (MCAO) model.

Cerebral ischemia-reperfusion injury (CIRI) occurs frequently clinically as a complication following cardiovascular resuscitation resulting in neuronal damage specifically to the hippocampal CA1 region with consequent cognitive impairment. Apoptosis and oxidative stress were proposed as major risk factors associated with CIRI development. Previously, glycosides obtained from Cistanche deserticola (CGs) were shown to play a key role in counteracting CIRI; however, the underlying mechanisms remain to be determined. This study aimed to investigate the neuroprotective effect of CGs on subsequent CIRI in rats. The model of CIRI was established for 2 hr and reperfusion for 24 hr by middle cerebral artery occlusion (MCAO) model. The MCAO rats were used to measure the antioxidant and anti-apoptotic effects of CGs on CIRI. Neurological function was evaluated by the Longa neurological function score test. 2,3,5-Triphenyltetrazolium chloride (TTC) staining was used to detect the area of cerebral infarction. Nissl staining was employed to observe neuronal morphology. TUNEL staining was used to detect neuronal apoptosis, while Western blot determined protein expression levels of factors for apoptosis-related and PI3K/AKT/Nrf2 signaling pathway. Data demonstrated that CGs treatment improved behavioral performance, brain injury, and enhanced antioxidant and anti-apoptosis in CIRI rats. In addition, CGs induced activation of PI3K/AKT/Nrf2 signaling pathway accompanied by inhibition of the expression of apoptosis-related factors. Evidence indicates that CGs amelioration of CIRI involves activation of the PI3K/AKT/Nrf2 signaling pathway associated with increased cellular viability suggesting these glycosides may be considered as an alternative compound for CIRI treatment.

Maresin1 alleviates neuroinflammation by inhibiting caspase-3/ GSDME-mediated pyroptosis in mice cerebral ischemia-reperfusion model.

OBJECTIVE: To explore the mechanism of Maresin1 in reducing cerebral ischemia-reperfusion injury. MATERIALS AND METHODS: Male C57BL/6 mice were randomly divided (n = 5 in each group), and focal middle cerebral artery occlusion (MCAO) model was used to simulate cerebral ischemia/reperfusion injury. TTC and the Longa score were used to detect the degree of neurological deficits. Western blot was used to detect the expression levels of GSDME, GSDME-N, caspase-3 and cleaved caspase-3 in cerebral ischemic penumbra tissue, and immunofluorescence was used to detect the expression levels of GSDME-N. The mRNA expression levels of GSDME and pro-inflammatory cytokines (IL-1ß, IL-6 and TNF-α) were detected by RT-PCR. RESULTS: Compared with sham group, GSDME mRNA levels in MCAO group were significantly increased at 12 h and 24 h after reperfusion, and GSDME and GSDME-N significantly increased at 6-48 h after reperfusion. Compared with sham group, the percentage of infarct size, the Longa score, the mRNA expression levels of IL-1ß, IL-6 and TNF-α, and GSDME, GSDME-N, caspase-3 and cleaved caspase-3 in MCAO group was significantly increased. Then, the percentage of infarct size and the Longa score significantly decreased after MaR1 administration, the mRNA expression levels of IL-1ß and IL-6 downregulated, and GSDME, GSDME-N, caspase-3 and cleaved caspase-3 were also reduced. After administration of Z-DEVD-FMK(ZDF), the expression of caspase-3, cleaved caspase-3 and GSDME-N was decreased, which in MCAO+MaR1+ZDF group was not statistically significant compared with MCAO+ ZDF group. CONCLUSION: Maresin1 alleviates cerebral ischemia/reperfusion injury by inhibiting pyroptosis mediated by caspase-3/GSDME pathway and alleviating neuroinflammation.

Shikonin attenuates cerebral ischemia/reperfusion injury via inhibiting NOD2/RIP2/NF-κB-mediated microglia polarization and neuroinflammation.

OBJECTIVES: Microglia-mediated neuroinflammation plays a crucial role in the pathophysiological process of multiple neurological disorders such as ischemic stroke, which still lacks effective therapeutic agents. Shikonin possesses anti-inflammatory and neuroprotective properties. However, its underlying mechanism remains elusive. This study aimed to investigate whether Shikonin confers protection against cerebral ischemia/reperfusion (I/R) injury by modulating microglial polarization and elucidate the associated mechanisms. METHODS: This study employed an oxygen-glucose deprivation and reoxygenation (OGD/R) BV2 microglial cellular model and a middle cerebral artery occlusion/reperfusion (MCAO/R) animal model to investigate the protection and underlying mechanism of Shikonin against ischemic stroke. RESULTS: The results demonstrated that Shikonin treatment significantly reduced brain infarction volume and improved neurological function in MCAO/R rats. Simultaneously, Shikonin treatment significantly reduced microglial proinflammatory phenotype and levels of proinflammatory markers (inducible-NO synthase (iNOS), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß), and IL-6), increased microglial anti-inflammatory phenotype and levels of anti-inflammatory markers (Arginase-1 (Arg1), transforming growth factor-beta (TGF-ß), and IL-10), reversed the expression of Nucleotide-binding oligomerization domain 2 (NOD2) and phosphorylation receptor interacting protein 2 (p-RIP2), and suppressed nuclear factor kappa-B (NF-κB) signaling activation in the ischemic penumbra regions. These effects of Shikonin were further corroborated in OGD/R-treated BV2 cells. Furthermore, overexpression of NOD2 markedly attenuated the neuroprotective effects of Shikonin treatment in MCAO/R rats. NOD2 overexpression also attenuated the regulatory effects of Shikonin on neuroinflammation, microglial polarization, and NF-κB signaling activation. CONCLUSION: This study illustrates that Shikonin mitigates inflammation mediated by microglial proinflammatory polarization by inhibiting the NOD2/RIP2/NF-κB signaling pathway, thereby exerting a protective role. The findings uncover a potential molecular mechanism for Shikonin in treating ischemic stroke.

Anti-apoptosis effect of traditional Chinese medicine in the treatment of cerebral ischemia-reperfusion injury.

Cerebral ischemia, one of the leading causes of neurological dysfunction of brain cells, muscle dysfunction, and death, brings great harm and challenges to individual health, families, and society. Blood flow disruption causes decreased glucose and oxygen, insufficient to maintain normal brain tissue metabolism, resulting in intracellular calcium overload, oxidative stress, neurotoxicity of excitatory amino acids, and inflammation, ultimately leading to neuronal cell necrosis, apoptosis, or neurological abnormalities. This paper summarizes the specific mechanism of cell injury that apoptosis triggered by reperfusion after cerebral ischemia, the related proteins involved in apoptosis, and the experimental progress of herbal medicine treatment through searching, analyzing, and summarizing the PubMed and Web Of Science databases, which includes active ingredients of herbal medicine, prescriptions, Chinese patent medicines, and herbal extracts, providing a new target or new strategy for drug treatment, and providing a reference for future experimental directions and using them to develop suitable small molecule drugs for clinical application. With the research of anti-apoptosis as the core, it is important to find highly effective, low toxicity, safe and cheap compounds from natural plants and animals with abundant resources to prevent and treat Cerebral ischemia/reperfusion (I/R) injury (CIR) and solve human suffering. In addition, understanding and summarizing the apoptotic mechanism of cerebral ischemia-reperfusion injury, the microscopic mechanism of CIR treatment, and the cellular pathways involved will help to develop new drugs.

Nrf2 attenuates oxidative stress to mediate the protective effect of ciprofol against cerebral ischemia-reperfusion injury.

Neuroinflammation and oxidative stress damage are involved in the pathogenesis of cerebral ischemia-reperfusion injury (CIRI). Ferroptosis emerged as a new player in the regulation of lipid peroxidation processes. This study aimed at exploring the potential involvement of ciprofol on ferroptosis-associated CIRI and subsequent neurological deficits in the mouse model of transient cerebral ischemia and reperfusion. Cerebral ischemia was built in male C57BL/6 J wild-type (WT) and Nrf2-knockout (Nrf2 KO) mice in the manner of middle cerebral artery occlusion (MCAO) followed by reperfusion. Ciprofol improved autonomic behavior, alleviated reactive oxygen species output and ferroptosis-induced neuronal death by nucleus transportation of NFE2 like BZIP transcription factor 2 (Nrf2) and the promotion of heme oxygenase 1 (Ho-1), solute carrier family 7 member 11 (SLC7A11/xCT), and glutathione peroxidase 4 (GPX4). Additionally, ciprofol improved neurological scores and reduced infarct volume, brain water content, and necrotic neurons. Cerebral blood flow in MCAO-treated mice was also improved. Furthermore, absence of Nrf2 abrogated the neuroprotective actions of ciprofol on antioxidant capacity and sensitized neurons to oxidative stress damage. In vitro, the primary-cultured cortical neurons from mice were pre-treated with oxygen-glucose deprivation/reperfusion (OGD/R), followed by ciprofol administration. Ciprofol effectively reversed OGD/R-induced ferroptosis and accelerated transcription of GPX4 and xCT. In conclusion, we investigated the ciprofol-induced inhibition effect of ferroptosis-sheltered neurons from lipid preoxidation in the pathogenesis of CIRI via Nrf2-xCT-GPX4 signaling pathway.

Lipocalin-2-mediated astrocyte pyroptosis promotes neuroinflammatory injury via NLRP3 inflammasome activation in cerebral ischemia/reperfusion injury.

BACKGROUND: Neuroinflammation is a vital pathophysiological process during ischemic stroke. Activated astrocytes play a major role in inflammation. Lipocalin-2 (LCN2), secreted by activated astrocytes, promotes neuroinflammation. Pyroptosis is a pro-inflammatory form of programmed cell death that has emerged as a new area of research in stroke. Nevertheless, the potential role of LCN2 in astrocyte pyroptosis remains unclear. METHODS: An ischemic stroke model was established by middle cerebral artery occlusion (MCAO) in vivo. In this study, in vitro, oxygen-glucose deprivation and reoxygenation (O/R) were applied to cultured astrocytes. 24p3R (the LCN2 receptor) was inhibited by astrocyte-specific adeno-associated virus (AAV-GFAP-24p3Ri). MCC950 and Nigericin sodium salt (Nig) were used to inhibit or promote the activation of NLRP3 inflammasome pharmacologically, respectively. Histological and biochemical analyses were performed to assess astrocyte and neuron death. Additionally, the neurological deficits of mice were evaluated. RESULTS: LCN2 expression was significantly induced in astrocytes 24 h after stroke onset in the mouse MCAO model. Lcn2 knockout (Lcn2-/-) mice exhibited reduced infarct volume and improved neurological and cognitive functions after MCAO. LCN2 and its receptor 24p3R were colocalized in astrocytes. Mechanistically, suppression of 24p3R by AAV-GFAP-24p3Ri alleviated pyroptosis-related pore formation and the secretion of pro-inflammatory cytokines via LCN2, which was then reversed by Nig-induced NLRP3 inflammasome activation. Astrocyte pyroptosis was exacerbated in Lcn2-/- mice by intracerebroventricular administration of recombinant LCN2 (rLCN2), while this aggravation was restricted by blocking 24p3R or inhibiting NLRP3 inflammasome activation with MCC950. CONCLUSION: LCN2/24p3R mediates astrocyte pyroptosis via NLRP3 inflammasome activation following cerebral ischemia/reperfusion injury.

Single-cell RNA sequencing unveils Lrg1's role in cerebral ischemia‒reperfusion injury by modulating various cells.

BACKGROUND AND PURPOSE: Cerebral ischemia‒reperfusion injury causes significant harm to human health and is a major contributor to stroke-related deaths worldwide. Current treatments are limited, and new, more effective prevention and treatment strategies that target multiple cell components are urgently needed. Leucine-rich alpha-2 glycoprotein 1 (Lrg1) appears to be associated with the progression of cerebral ischemia‒reperfusion injury, but the exact mechanism of it is unknown. METHODS: Wild-type (WT) and Lrg1 knockout (Lrg1-/-) mice were used to investigate the role of Lrg1 after cerebral ischemia‒reperfusion injury. The effects of Lrg1 knockout on brain infarct volume, blood‒brain barrier permeability, and neurological score (based on 2,3,5-triphenyl tetrazolium chloride, evans blue dye, hematoxylin, and eosin staining) were assessed. Single-cell RNA sequencing (scRNA-seq), immunofluorescence, and microvascular albumin leakage tests were utilized to investigate alterations in various cell components in brain tissue after Lrg1 knockout. RESULTS: Lrg1 expression was increased in various cell types of brain tissue after cerebral ischemia‒reperfusion injury. Lrg1 knockout reduced cerebral edema and infarct size and improved neurological function after cerebral ischemia‒reperfusion injury. Single-cell RNA sequencing analysis of WT and Lrg1-/- mouse brain tissues after cerebral ischemia‒reperfusion injury revealed that Lrg1 knockout enhances blood‒brain barrier (BBB) by upregulating claudin 11, integrin ß5, protocadherin 9, and annexin A2. Lrg1 knockout also promoted an anti-inflammatory and tissue-repairing phenotype in microglia and macrophages while reducing neuron and oligodendrocyte cell death. CONCLUSIONS: Our results has shown that Lrg1 mediates numerous pathological processes involved in cerebral ischemia‒reperfusion injury by altering the functional states of various cell types, thereby rendering it a promising therapeutic target for cerebral ischemia‒reperfusion injury.

Global-Scale Profiling of Differential Expressed Lysine-Lactylated Proteins in the Cerebral Endothelium of Cerebral Ischemia-Reperfusion Injury Rats.

Acute ischemic stroke (AIS) is a serious threat to human health. Following AIS, cerebral ischemia-reperfusion injury (CIRI) must be treated to improve prognosis. By combining 4D label-free quantitative proteomics with lactylation modification-specific proteomics analysis, we assessed lysine lactylation (Kla) in cortical proteins of a CIRI rat model. We identified a total of 1003 lactylation sites on 469 proteins in this study, gathering quantitative information (PXD034232) on 660 of 310 proteins, which were further classified by cell composition, molecular function, and biological processes. In addition, we analyzed the metabolic pathways, domains, and protein-protein interaction networks. Lastly, we evaluated differentially expressed lysine lactylation sites, determining 49 upregulated proteins and 99 downregulated proteins with 54 upregulated sites and 54 downregulated sites in the experimental group in comparison with the healthy control group. Moreover, we identified the Kla of Scl25a4 and Slc25a5 in the Ca2+ signaling pathway, but the Kla of Vdac1 was eliminated, as confirmed in vivo. Overall, these results provide new insights into lactylation involved in the underlying mechanism of CIRI because this post-translational modification affects the mitochondrial apoptosis pathway and mediates neuronal death. Therefore, this study may enable us to develop new molecules with therapeutic properties, which have both theoretical significance and broad clinical application prospects. A new model of cerebral ischemia-reperfusion injury (CIRI) induced by lactylation through the regulation of key proteins of the Ca2+ signaling pathway.

Protective Effect of Hydrogen Sulfide on Cerebral Ischemia-Reperfusion Injury.

The brain is the most sensitive organ to hypoxia in the human body. Hypoxia in the brain will lead to damage to local brain tissue. When the blood supply of ischemic brain tissue is restored, the damage will worsen, that is, cerebral ischemia-reperfusion injury. Hydrogen sulfide (H2S) is a gaseous signal molecule and a novel endogenous neuroregulator. Indeed, different concentrations of H2S have different effects on neurons. Low concentration of H2S can play an important protective role in cerebral ischemia-reperfusion injury by inducing anti-oxidative stress injury, inhibition of inflammatory response, inhibition of cell apoptosis, reduction of cerebrovascular endothelial cell injury, regulation of autophagy, and other ways, which provides a new idea for clinical diagnosis and treatment of related diseases. This review aims to report the recent research progress on the dual effect of H2S on brain tissue during cerebral ischemia/reperfusion injury.

Stem Cell Therapies for Restorative Treatments of Central Nervous System Ischemia-Reperfusion Injury.

Ischemic damage to the central nervous system (CNS) is a catastrophic postoperative complication of aortic occlusion subsequent to cardiovascular surgery that can cause brain impairment and sometimes even paraplegia. Over recent years, numerous studies have investigated techniques for protecting and revascularizing the nervous system during intraoperative ischemia; however, owing to a lack of knowledge of the physiological distinctions between the brain and spinal cord, as well as the limited availability of testing techniques and treatments for ischemia-reperfusion injury, the cause of brain and spinal cord ischemia-reperfusion injury remains poorly understood, and no adequate response steps are currently available in the clinic. Given the limited ability of the CNS to repair itself, it is of great clinical value to make full use of the proliferative and differentiation potential of stem cells to repair nerves in degenerated and necrotic regions by stem cell transplantation or mobilization, thereby introducing a novel concept for the treatment of severe CNS ischemia-reperfusion injury. This review summarizes the most recent advances in stem cell therapy for ischemia-reperfusion injury in the brain and spinal cord, aiming to advance basic research and the clinical use of stem cell therapy as a promising treatment for this condition.

LncRNA CEBPA-AS1 alleviates cerebral ischemia-reperfusion injury by sponging miR-340-5p regulating APPL1/LKB1/AMPK pathway.

Long non-coding RNAs (lncRNAs) regulate neurological damage in cerebral ischemia-reperfusion injury (CIRI). This study aimed to investigate the biological roles of lncRNA CEBPA-AS1 in CIRI. Middle cerebral artery occlusion and ischemia-reperfusion injury (MCAO/IR) rat model and oxygen-glucose deprivation and reoxygenation (OGD/R) cell lines were generated; the expression of CEBPA-AS1 was evaluated by qRT-PCR. The effects of CEBPA-AS1 on cell apoptosis and nerve damage were examined. The downstream microRNA (miRNA) and mRNA of CEBPA-AS1 were predicted and verified. We found that overexpression of CEBPA-AS1 could attenuate MCAO/IR-induced nerve damage and neuronal apoptosis in the rat model. Knockdown of CEBPA-AS1 aggravated cell apoptosis and enhanced the production of LDH and MDA in the OGD/R cells. Upon examining the molecular mechanisms, we found that CEBPA-AS1 stimulated APPL1 expression by combining with miR-340-5p, thereby regulating the APPL1/LKB1/AMPK pathway. In the rescue experiments, CEBPA-AS1 overexpression was found to attenuate OGD/R-induced cell apoptosis and MCAO/IR induced nerve damage, while miR-340-5p reversed these effects of CEBPA-AS1. In conclusion, CEBPA-AS1 could decrease CIRI by sponging miR-340-5, regulating the APPL1/LKB1/AMPK pathway.

The lncRNA NEAT1 Mediates Neuronal Cell Autophagy and Related Protein Expression After Cerebral Ischemia‒Reperfusion Injury.

The present study focuses on the role of the long noncoding RNA (lncRNA) NEAT1 in regulating autophagy during the ischemia‒reperfusion (I/R) injury process and its possible regulatory mechanism based on the results of laboratory experiments. Neuro-2a (N2a) cells and BV-2 microglial cells were cultured separately, and oxygen-glucose deprivation/reoxygenation (OGD/R) was induced in vitro to mimic cerebral I/R injury. The expression of lncRNA NEAT1 was measured after reoxygenation for different durations, and the results showed that NEAT1 expression was significantly different after OGD/R for 12 h; thus, cell models of NEAT1 overexpression and knockdown were constructed. Knockdown of NEAT1 effectively relieved reperfusion injury. In an N2a and BV-2 cell coculture system, knockdown of NEAT1 reduced autophagic flow in neuronal cells after reperfusion. To clarify the mechanism of NEAT1 after neuronal I/R injury, label-free quantitative proteomics (LFQ) was used to identify the differentially expressed proteins (DEPs) in NEAT1 knockdown neurons after OGD/R for 12 h. Additionally, Gene Ontology (GO) enrichment, protein‒protein interaction (PPI) network and parallel-reaction monitoring (PRM) quantitative analyses were carried out; the results showed that the expression levels of the autophagy-related proteins Gaa, Glb1, Prkaa1, Kif23, Sec24a and Vps25 were significantly reduced and that these proteins interact. In summary, this study shows that NEAT1 can regulate the interactions between autophagy-related proteins after neuronal I/R injury, reducing the level of autophagy and relieving neuronal reperfusion injury.

MicroRNA-27a Regulates Ferroptosis Through SLC7A11 to Aggravate Cerebral ischemia-reperfusion Injury.

Cerebral ischemia-reperfusion (I/R) injury is an inevitable issue in the treatment of ischemic stroke, which has a high disability rate and seriously threatens the living quality of patients. Previous studies have demonstrated that ferroptosis, which plays a crucial role in ischemia-reperfusion injury, can be accelerated by microRNA-27a (miR-27a). However, the mechanism by which miR-27a regulates ferroptosis in cerebral ischemia-reperfusion injury remains unknown. In this study, Male Sprague-Dawley rats were subjected to a middle cerebral artery occlusion (MCAO), then restored blood flow. Neurological function score and TTC staining were used to evaluate brain tissue injury and the infarct volume. The relative expression level of miR-27a was detected by qPCR. The relative expression levels of glutathione peroxidase 4(GPx4), solute carrier family 7 member 11 (SLC7A11) proteins were analyzed by Western Blot. The contents of GSH, Fe and malonaldehyde (MDA) were detected by corresponding detection kits, and the target gene of miR-27a was confirmed by dual luciferase reporter gene technique. It was found the relative expression level of miR-27a was increased and ferroptosis was aggravated as reperfusion time went by. Also, brain tissue injury and ferroptosis were exacerbated with agomiR-27a intervention, while these effects were reversed with antagomiR-27a intervention. In addition, the combined intervention of agomiR-27a and Fer-1 alleviated the brain tissue injury and ferroptosis. The results of dual luciferase reporter gene technique indicated SLC7A11 as the target gene of miR-27a. In the current study, miR-27a upregulates ferroptosis to aggravate cerebral ischemia-reperfusion injury by SLC7A11.