Oxygen-glucose Deprivation/reoxygenation Research Articles

Protective Role of Oxycodone in Myocardial Oxidative Stress and Mitochondrial Dysfunction Induced by Ischemia-Reperfusion.

Ischemia-reperfusion (I/R) injury is a significant clinical problem impacting the heart and other organs, such as the kidneys and liver. This study explores the protective effects of oxycodone on myocardial I/R injury and its underlying mechanisms. Using a myocardial I/R model in Sprague-Dawley (SD) rats and an oxygen-glucose deprivation/reoxygenation (OGD/R) model in H9c2 cells, we administered oxycodone and inhibited AMP-activated protein kinase (AMPK) with Compound C (C.C). Our results showed that oxycodone significantly reduced lactate dehydrogenase (LDH) release and reactive oxygen species (ROS) production while stabilizing mitochondrial membrane potential (MMP). Western blot and RT-qPCR analyzes confirmed that oxycodone enhances AMPK phosphorylation and upregulates the expression of Silent Information Regulator 1 (SIRT1) and Peroxisome Proliferator-Activated Receptor γ Coactivator 1α (PGC-1α), thereby protecting myocardial cells. These findings suggest that oxycodone exerts significant protective effects against I/R injury by activating the AMPK pathway, offering new potential therapeutic targets for myocardial protection.

S100A8-CAMKK2-AMPK axis confers the protective effects of mild hypothermia against cerebral ischemia-reperfusion injury in rats

To investigate the neuroprotective mechanism of mild hypothermia (MH) in ameliorating cerebral ischemia reperfusion (IR) injury. The Pulsinelli’s four-vessel ligation method was utilized to establish a rat model of global cerebral IR injury. To investigate the role of S100A8 in MH treatment of cerebral IR injury, hippocampus-specific S100A8 loss or gain of function was achieved using an adeno-associated virus system. We examined the effect of S100A8 over-expression or knock-down on the function of the SH-SY5Y cell line subjected to oxygen-glucose deprivation reoxygenation (OGDR) injury under MH treatment and delved into the underlying mechanisms. MH significantly ameliorates IR-induced neurological injury in the brain. Similarly to MH, knock-down of S100A8 significantly reduced neuronal oxidative stress, attenuated mitochondrial damage, inhibited apoptosis, and improved cognitive function in IR rats. Conversely, over-expression of S100A8 attenuated MH’s protective effect and aggravated brain IR injury. In vitro, low expression of S100A8 significantly inhibited the decline in mitochondrial membrane potential induced by OGDR, reduced oxidative stress response, and decreased cell apoptosis, acting as a protective agent nearly equivalent to MH in SH-SY5Y cells. However, over-expression of S100A8 significantly inhibited these protective effects of MH. Mechanistically, MH down-regulated S100A8 expression, enhancing mitochondrial function via activation of the CAMKK2/AMPK signaling pathway. Moreover, with MH treatment, the administration of CAMKK2 and AMPK inhibitors STO-609 and Dorsomorphin significantly increased oxidative stress, mitochondrial damage, and cell apoptosis, thereby diminishing MH’s neuroprotective effect against cerebral IR injury. Our study identified S100A8 as a master regulator that enables MH to ameliorate neurological injury during the early stage of cerebral IR injury by enhancing mitochondrial function. By targeting the S100A8-initiated CAMKK2/AMPK signaling pathway, we may unlock a novel therapeutic intervention or develop a refined MH therapeutic strategy against cerebral IR injury.

Ginkgolide B binds to GPX4 and FSP1 to alleviate cerebral ischemia/reperfusion injury in rats.

Ischemia/reperfusion (I/R) injury can increase the anomalous permeability of the blood-brain barrier and the risk of hemorrhagic conversion. Ginkgolide B (Gin B) has been recognized for its neuroprotective properties in stroke treatment. This study aimed to analyze the association of Gin B with GPX4 and FSP1 in cerebral I/R injury treatment. HT22 cells were induced by oxygen-glucose deprivation/reoxygenation (OGD/R) and treated with a series of Gin B (10, 20, 40 μM) for 24 h. It found that the Gin B treatment declined the OGD/R-induced cellular ROS and lipid ROS with increasing concentrations. Moreover, the Gin B treatment improved the OGD/R-induced ferroptotic cell death by activating the GPX4-GSH and FSP1-CoQ10-NADH pathways with increasing concentrations. Molecular docking showed there is a good binding activity of Gin B to GPX4 (score = -6.4 kcal/mol) and FSP1 (score = -6.7 kcal/mol), and the microscale thermophoresis (MST) assay confirmed that Gin B can directly bind to GPX4 and FSP1. In vivo, rats were induced by middle cerebral artery occlusion (MCAO)/R and treated with 20 mg/kg of Gin B to analyze its effects on the GPX4-GSH and FSP1-CoQ10-NADH pathways. The GPX4 inhibitor (RSL3) and the FSP1 inhibitor (iFSP1) were used to confirm the mechanism of Gin B in the MCAO/R-treated rats. It showed that the Gin B treatment alleviated the MACO/R-induced brain injury by activating the GPX4-GSH and FSP1-CoQ10-NADH pathways. This study showed that Gin B improved cerebral I/R-induced ferroptotic cell death by activating the GPX4-GSH and FSP1-CoQ10-NADH pathways, providing a new mechanism of Gin B for cerebral I/R treatment.

Mogroside V ameliorates astrocyte inflammation induced by cerebral ischemia through suppressing TLR4/TRADD pathway.

Inflammation and oxidative stress are pivotal factors in the onset and progression of secondary injury following cerebral ischemia-reperfusion (I/R). Mogroside V (MV), a primary active compound of Siraitia grosvenorii, exhibits significant anti-inflammatory and antioxidant properties. However, its specific effects in cerebral ischemia remain unclear. In this study, we evaluated the neuroprotective effects of MV in a model of focal cerebral ischemia. Male C57BL/6J mice were subjected to middle cerebral artery occlusion/reperfusion (MCAO/R) as an in vivo model of cerebral ischemia-reperfusion injury (CIRI), while U87 cells were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to simulate CIRI in vitro. MV administration was found to reduce mortality, infarct volume, cerebral edema, and alleviate neurological deficits in these I/R mice. Furthermore, MV mitigated cerebral I/R injury by decreasing oxidative stress markers, such as reactive oxygen species (ROS) and malondialdehyde (MDA), while enhancing superoxide dismutase (SOD) levels. Gene Set Enrichment Analysis (GSEA) of the KEGG pathway revealed that most differentially expressed genes (DEGs) were involved in the Toll-like receptor/NF-κB/TNF/apoptosis signaling pathway. These findings were confirmed by real-time PCR, western blotting, immunohistochemistry, and immunofluorescence co-localization which demonstrated that MV reduced astrocyte inflammatory responses by inhibiting cytokine secretion associated with the TLR4/TRADD pathway. Additionally, MV protected neurons from apoptosis, as supported by TUNEL, Nissl, and HE staining. In conclusion, MV attenuates astrocyte inflammation and exerts neuroprotective effects following cerebral I/R injury, likely through suppression of the TLR4/TRADD signaling pathway.

Qingda Granules alleviate brain damage in spontaneously hypertensive rats by modulating the miR-124/STAT3 signaling axis.

To explore the mechanism of Qingda Granules (QDG) for alleviating brain damage in spontaneously hypertensive rats (SHRs). Twelve 5-week-old SHRs were randomized into SHR control group and SHR+QDG group treated with QDG by gavage at the daily dose of 0.9 g/kg for 12 weeks. The control rats, along with 6 age-matched WKY rats, were treated with saline only. Blood pressure changes of the rats were monitored, and pathologies and neuronal apoptosis in the cerebral cortex were examined with HE staining and TUNEL staining. Cerebral cortical expressions of miR-124 and STAT3 mRNA were detected using RT-qPCR, and the protein expressions of NeuN, STAT3, Bcl-2, Bax, and cleaved caspase-3 were detected with immunohistochemistry and Western blotting. In a HT22 cell model of oxygen and glucose deprivation/reoxygenation (OGD/R), the effects of QDG on cell viability and apoptosis, expressions of miR-124 and STAT3 mRNA, and protein expressions of STAT3, Bcl-2, Bax, and cleaved caspase-3 were evaluated using CCK8 assay, Hoechst 33342 staining, RT-qPCR, and Western blotting. Compared with WKY rats, SHRs had significantly elevated systolic blood pressure, diastolic blood pressure and mean arterial pressure with significantly increased neuronal apoptosis in the cerebral cortex, reduced expressions of NeuN, miR-124 and Bcl-2, and enhanced expressions of STAT3, Bax and cleaved caspase-3 (P<0.05). All these changes in the SHRs were significantly ameliorated by treatment with QDG (P<0.05). In the HT22 cell model, QDG treatment obviously reduced OGD/R-induced cell apoptosis, increased the expressions of miR-124 and Bcl-2, and suppressed the elevation of protein expressions of STAT3, Bax and cleaved caspase-3. QDG inhibits cerebral cortical neuronal apoptosis and thereby attenuates brain damage in SHR rats by modulating the miR-124/STAT3 signaling axis.

Laminin-dystroglycan mediated ferroptosis in hemorrhagic shock and reperfusion induced-cognitive impairment through AMPK/Nrf2.

Hemorrhagic shock and reperfusion (HSR) is the main cause of death following trauma. Cognitive impairment may persist after successful resuscitation from hemorrhagic shock, but the mechanisms remain elusive. This study demonstrated the presence of ferroptosis in an in vitro model of oxygen-glucose deprivation and reoxygenation (OGD/R) in HT22 neurons, and also in a murine model of HSR using 3-month-old C57BL/6 mice. The ferroptosis induced by OGD/R was characterized by transmission electron microscopy, the localization of FTH1 and TFR1 in HT22 cells. However, neuronal ferroptosis was prevented by suppressing AMPK through siRNA transfection or AMPK inhibitor pretreatment (compound C) in vitro. There was a consistent increase in Nrf2 with ROS accumulation, iron deposition, and lipid peroxidation in the hippocampal neurons and tissues. Nrf2 knockdown or overexpression significantly modulated OGD/R induced-ferroptosis. Activating ferroptosis by erastin (a ferroptosis inducer) or inhibiting it by ferrostatin-1 (a ferroptosis inhibitor) respectively enhanced or mitigated cognitive deficits as well as the ferroptosis-related changes induced by HSR. In addition to the improved cognition, single-nucleus transcriptome analysis of ipsilateral hippocampi from Nrf2-/- mice demonstrated the broad decrease of ferroptosis in neuronal cell clusters. LAMA2 and DAG1 were dominantly elevated and co-localized in the hippocampal CA3 region of Nrf2-/- mice by fluorescence in situ hybridization. The activation of astrocytes was significantly attenuated after Nrf2 knockout, associated with the increases of laminin-dystroglycan during astrocyte-neuron crosstalk. Thus, data from this study proposes a novel explanation, namely laminin-dystroglycan interactions during astrocytes-neurons crosstalk stimulating AMPK and Nrf2 induced neuronal ferroptosis, for the development of cognitive impairment after HSR.

Curcumin Regulates Microglia Polarization to Alleviate Ischemic Stroke by Targeting microRNA-205-5p/Kruppel-Like Factor 2 (KLF2)/Activating Transcription Factor 2 (ATF2) Axis.

Ischemic stroke (IS) often causes fearful sequela, even death. Curcumin was beneficial to IS, but its underlying molecular mechanism is unclear. Mice were subjected to middle cerebral artery occlusion (MCAO) surgery, and BV-2 cells were treated with oxygen-glucose deprivation/reoxygenation (OGD/R) induction to establish IS models invivo and invitro. Abundance of genes and proteins was determined using quantitative real-time polymerase chain reaction (RT-qPCR), immunofluorescence (IF), and western blot. Interleukin-1β (IL-1β), interleukin-6 (IL-6), and interleukin-10 (IL-10) levels were analyzed using enzyme-linked immunosorbent assay (ELISA). Modified neurological severity score (mNSS), corner test, foot fault test, adhesive removal test, and 2,3,5-triphenyltetrazolium chloride (TTC) staining were applied to evaluate the brain injury of mice. The correlation between miR-205-5p and Kruppel-like factor 2 (KLF2) was affirmed using dual luciferase reporter assay. Our results revealed that curcumin alleviated brain damage in MCAO mice through driving microglia M2 polarization. Of note, curcumin resulted in decreased miR-205-5p expression in MCAO mice. miR-205-5p knockdown resulted in promoted microglia M2 polarization in OGD/R conditions and achieved similar results to curcumin treatment in MCAO mice. Moreover, curcumin played a promoting role in microglia M2 polarization under OGD/R conditions, while miR-205-5p overexpression or KLF2 knockdown abolished these effects. On the mechanism, miR-205-5p was a target of curcumin, and miR-205-5p further interacted with KLF2 to inhibit activating transcription factor 2 (ATF2) expression. miR-205-5p, decreased by curcumin, suppressed microglia M2 polarization to worsen IS injury through the mediating KLF2/ATF2 axis.

Disruption of the Pum2 axis Aggravates neuronal damage following cerebral Ischemia-Reperfusion in mice.

Stroke remains a leading cause of disability and mortality worldwide, with mitochondrial dysfunction closely linked to ischemic injury. This study explores the Norad-Pum2-Mff axis as a key regulator of mitochondrial function following ischemia-reperfusion (I/R) injury. Using an oxygen-glucose deprivation/reoxygenation (OGD/R) model, Mff protein levels were significantly elevated post-OGD/R, while mRNA levels remained unchanged, suggesting post-transcriptional regulation. Pumilio2 (Pum2), an RNA-binding protein, was shown to inhibit Mff translation, while Norad, a long non-coding RNA, sequestered Pum2, alleviating this inhibition. We observed decreased Pum2 levels and binding capacity to Mff mRNA, alongside increased Norad levels and binding to Pum2 in neurons after OGD/R. Overexpression of Pum2 in neurons reduced Mff levels, mitigated mitochondrial fragmentation, and alleviated neuronal injury. In a mouse model of middle cerebral artery occlusion/reperfusion (MCAO/R), Pum2 overexpression further improved mitochondrial morphology, reduced infarct volume, and enhanced neurobehavioral recovery. These findings suggest that targeting the Norad-Pum2-Mff axis could provide a promising therapeutic strategy for ischemic stroke by restoring mitochondrial function and reducing neuronal damage.

Oxyglutamate Carrier Alleviates Cerebral Ischaemia-Reperfusion Injury by Regulating Mitochondrial Function.

Mitochondrial dysfunction has been reported to participate in the pathophysiological processes of cerebral ischaemia-reperfusion injury, which include reduced energy homeostasis, increased generation of oxidative stress species (ROS) and the release of apoptotic factors. Oxyglutamate carrier (OGC) is an important carrier protein on the inner mitochondrial membrane that can transport metabolites from the cytoplasm to the mitochondria. The role of OGC in cerebral ischaemia-reperfusion injury (I/R) remains unknown. In this study, we found that the expression of OGC was significantly upregulated after cerebral ischaemia-reperfusion injury. Inhibiting OGC with phenylsuccinic acid (PSA) increased neuronal death after oxygen-glucose deprivation/reoxygenation (OGD/R) invitro. Mechanistically, OGC was localized in mitochondria and could facilitate the transport of glutathione from the cytoplasm to the mitochondria to reduce ROS levels and increase ATP production after OGD/R. In addition, invivo inhibition of OGC exacerbated brain infarction, and GSH supplementation alleviated brain infarction resulting from OGC inhibition. This study revealed the role of OGC in alleviating brain damage by regulating mitochondrial GSH transport to alleviate mitochondrial function after cerebral ischaemia-reperfusion injury, which may provide a target for alleviating ischaemic brain injury.

Yangyin Yiqi Huoxue Decoction improves the mechanism of microglia activation against CIS-induced neuroinflammatory injury by regulating the Wnt signaling pathway.

Ischemic stroke is a predominant cause of neurological disability, characterized by neuroinflammation and neuronal apoptosis. The Wnt signaling pathway plays a critical role in brain repair. Yangyin Yiqi Huoxue Decoction, a traditional Chinese herbal formula, has shown potential in alleviating neuroinflammatory injury, yet, the precise mechanism underlying its effects remains unclear. This study aims to explore the therapeutic efficacy of Yangyin Yiqi Huoxue Decoction on ischemic stroke and its potential mechanism of action, particularly focusing on its modulation of the Wnt signaling pathway and impact on neuroinflammation and neural stem cells activity. The middle cerebral artery occlusion (MCAO) rat model and an Oxygen glucose deprivation/re-oxygenation (OGD/R) cell model were employed. In vivo experiments were conducted to investigate the therapeutic effects of the Yangyin Yiqi Huoxue Decoction at high, medium, and low dosages (3.3, 1.65, and 0.83 g/kg). The effects of Yangyin Yiqi Huoxue Decoction on neuroinflammatory cytokine levels, microglial activation, and neural stem cells proliferation and differentiation were assessed in vivo experiments. Wnt signaling components were evaluated through Quantitative Real-Time PCR and Western blot in both vivo and vitro. Additionaly, the Wnt inhibitor Dickkopf-related protein 1(DKK1) was used to confirm the pathway's involvement. The high-dose group(3.3 g/kg) of the Yangyin Yiqi Huoxue Decoction exhibited the most pronounced therapeutic effects. Yangyin Yiqi Huoxue Decoction significantly reduced pro-inflammatory cytokine levels, inhibited microglial overactivation, and enhanced neural stem cells proliferation and differentiation. It also modulated the Wnt pathway by upregulating Wnt Family Member 3A(Wnt3a) and β-catenin, while downregulating Wnt Family Member 5A(Wnt5a) and glycogen synthase kinase-3β(GSK-3β). The inhibition of Wnt signaling by Dickkopf-related protein 1(DKK1) reversed these beneficial effects, confirming Yangyin Yiqi Huoxue Decoction 's mechanism. Yangyin Yiqi Huoxue Decoction exerts neuroprotective effects by suppressing neuroinflammation and promoting neural-stem-cell-mediated brain repair through the Wnt signaling pathway, positioning it as a potential candidate for ischemic stroke treatment.

Gastrodin: Modulating the xCT/GPX4 and ACSL4/LPCAT3 pathways to inhibit ferroptosis after ischemic stroke.

This research endeavors to probe Gastrodin's influence on post-ischemic ferroptosis, deciphering its mechanisms and assessing its therapeutic promise. We developed rat models of middle cerebral artery occlusion/reperfusion (MCAO/R) and created oxygen-glucose deprivation/reoxygenation (OGD/R)-damaged PC12 cell models. Gastrodin was administered to assess ferroptosis using Prussian blue staining and fluorescence probes. To investigate the effects of gastrodin on the xCT/GPX4 and ACSL4/LPCAT3 pathways, we employed molecular docking, immunofluorescence, Western blotting, and quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, we used transmission electron microscopy and JC-1 fluorescence probes to examine mitochondrial integrity and function. Our study demonstrated that gastrodin significantly reduced iron accumulation and lipid peroxidation in the brains of MCAO/R rats and OGD/R-injured PC12 cells. It suppressed reactive oxygen species (ROS) and ameliorated mitochondrial membrane potential. It potentiates the xCT/GPX4 axis while repressing the ACSL4/LPCAT3 pathway, leading to improved mitochondrial architecture and function, notably characterized by decreased mitochondrial membrane potential, reduced ROS levels, and increased formation of mitochondrial cristae. By modulating the xCT/GPX4 and ACSL4/LPCAT3 pathways, gastrodin mitigated ferroptosis in ischemic stroke, thereby preserving mitochondrial structural and functional integrity. This study provides novel mechanistic insights into gastrodin's therapeutic potential for treating ischemic stroke, highlighting the importance of traditional Chinese medicine in modern medical therapy.

Na+-K+-ATPase/GLT-1 interaction participates in EGCG protection against cerebral ischemia-reperfusion injury in rats.

In China, stroke is the primary cause of adult death and disability. Because of the increased rate of blood vessel reperfusion, it is important to prevent cerebral ischemia-reperfusion injury, in which glutamate (Glu) excitotoxicity plays a critical role. The most important Glu transporter, GLT-1, is essential for the regulation of Glu, which is dependent on Na+-K+-ATPase (NKA)-induced ion concentration gradient differences. EGCG, a substance found in tea polyphenols, can reduce infarct areas in ischemia-reperfusion models, reduce stroke incidence, and prolong life in which NKA is involved. In this study, we investigated the potential of EGCG in protecting against cerebral ischemia-reperfusion injury by regulating the interaction between NKA and GLT-1. This study was designed to investigate the protective effects of EGCG against cerebral ischemia-reperfusion injury by modulating the interaction between NKA and GLT-1, utilizing both the rat middle cerebral artery occlusion/reperfusion (MCAO/R) model and the oxygen-glucose deprivation/reoxygenation (OGD/R) model in co-cultures of rat hippocampal neurons and astrocytes. The neuronal survival rate was assessed using CCK8, and the cerebral infarction area and neurological function were determined by TTC staining and neurological deficit scores. NKA activity was measured using an inorganic phosphorous detection method, and NKA and GLT-1 expression was detected using western blotting. The interaction between NKAα2 and GLT-1 was identified by co-immunoprecipitation (CoIP) assay, laser confocal microscopy, and Imaris 3D confocal rendering technology. An adenovirus vector with overexpression of NKAα2 was constructed, packaged, and injected into the rat lateral ventricle. Neurological function and the cerebral infarction area were identified, and the interaction between NKAα2 and GLT-1 was identified using CoIP assay. EGCG reduced the infarction area and neurological deficit scores, restored NKA activity, alleviated the decrease in membrane NKAα2 and GLT-1 expression, and relieved the uncoupling of NKAα2 and GLT-1 in the hippocampal CA1 after rat MCAO/R injury. By promoting the coupling of NKAα2 and GLT-1 in rat MCAO/R models, overexpression of NKAα2 reduced the cerebral infarction area and neurological impairment scores. EGCG improved cerebral ischemia-reperfusion injury by restoring NKA activity and increasing membrane GLT-1 expression due to NKA-GLT-1 interaction. For the first time, our findings demonstrate the critical role that NKA and GLT-1 colocalization plays in cerebral ischemia-reperfusion damage. Our findings provide new strategic directions for the pathogenesis and prevention of thrombolytic injury in the clinical treatment of stroke, while also serving as a basis for further development and utilization of EGCG.

DNA2 knockout aggravates cerebral ischemia/reperfusion injury by reducing postsynaptic Homer1a.

DNA2, a multifunctional enzyme with structure-specific nuclease, 5 '-to-3 ' helicase, and DNA-dependent ATPase activities, plays a pivotal role in the cellular response to DNA damage. However, its involvement in cerebral ischemia/reperfusion (I/R) injury remains to be elucidated. This study investigated the involvement of DNA2 in cerebral I/R injury using conditional knockout (cKO) mice ( Nestin-Cre) subjected to middle cerebral artery occlusion (MCAO), an established model of cerebral I/R. Results demonstrated a gradual up-regulation of DNA2 expression, peaking at 72 h post-MCAO. Notably, DNA2 cKO mice exhibited more pronounced brain injury, neurological deficits, and neuronal apoptosis within the penumbra following MCAO. Additionally, DNA2 expression was elevated in an oxygen-glucose deprivation/reoxygenation (OGD/R) cell culture model, and DNA2 knockdown (KD) exacerbated neuronal apoptosis and oxidative stress. Transcriptome analysis of ischemic penumbra tissues via RNA sequencing revealed significant down-regulation of Homer1 in DNA2 cKO mice. Furthermore, in vitro experiments demonstrated that overexpression of Homer1a ameliorated DNA2 KD-induced neuronal apoptosis. Collectively, these findings demonstrate that DNA2 deficiency exacerbates cerebral I/R injury through the down-regulation of Homer1a, highlighting a novel regulatory axis in ischemic neuroprotection.

Therapeutic potential of microglial SMEK1 in regulating H3K9 lactylation in cerebral ischemia-reperfusion

Acute ischemic stroke (AIS) triggers immune responses and neuroinflammation, contributing to brain injury. Histone lactylation, a metabolic stress-related histone modification, plays a critical role in various diseases, but its involvement in cerebral ischemia remains unclear. This study utilized a transient middle cerebral artery occlusion/reperfusion (MCAO/R) model and an oxygen–glucose deprivation/reoxygenation (OGD/R) model to investigate the role of microglial histone lactylation in ischemia–reperfusion injury. Lactate overload post-AIS increased histone lactylation, while reduced SMEK1 expression in microglia correlated with elevated lactate and neuroinflammation. Microglia-specific SMEK1 deficiency enhanced lactate production by inhibiting the pyruvate dehydrogenase kinase 3-pyruvate dehydrogenase (PDK3-PDH) pathway, increasing H3 lysine 9 lactylation (H3K9la), activating Ldha and Hif-1α transcription, and promoting glycolysis. SMEK1 overexpression improved neurological recovery in ischemic mice. This study highlights SMEK1 as a novel regulator of histone lactylation and a potential therapeutic target for mitigating neuroinflammation and enhancing recovery after AIS.

HUC-MSC extracellular vesicles protect against hypoxic-ischemic brain injury by promoting NLRP3 ubiquitination.

Hypoxic-ischemic brain injury (HIBD) is a major cause of neonatal mortality and long-term neurological deficits, with limited treatment options. Extracellular vesicles (EVs) from human umbilical cord mesenchymal stem cells (hUC-MSC-EVs) have shown promise in neuroprotection, but the mechanisms remain unclear. This study explores how hUC-MSC-EVs protect neonatal rats from HIBD. hUC-MSC-EVs were isolated, characterized, and administered to neonatal rats subjected to HIBD. Behavioral reflexes and brain infarction were assessed, along with cellular and molecular analyses of hippocampal tissue. An in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) model was used to simulate ischemic conditions in rat primary microglia. Results demonstrated that hUC-MSC-EVs significantly improved neurological outcomes, reduced brain infarction, and decreased microglial activation and pyroptosis. These effects were linked to the inhibition of NLRP3 inflammasome activation and enhanced ubiquitination via the protein kinase A (PKA) pathway. Blocking PKA partially reversed these protective effects. Here we highlight that hUC-MSC-EVs provide neuroprotection by regulating the NLRP3 inflammasome, offering a potential therapeutic strategy for HIBD. These findings expand the understanding of EV-mediated neuroprotection and suggest broader applications for ischemia-related conditions, with potential for clinical translation.

Xiaoxuming decoction enhanced neuroprotection after cerebral ischemia/reperfusion via the JAK2/STAT3 signaling pathway based on UPLC/HRMS, network pharmacology and experimental validation.

Xiao-xu-ming decoction (XXMD), a prominent traditional Chinese medicinal formula historically revered for stroke treatment, demonstrates pronounced efficacy in ameliorating ischemic stroke injury. This study aims to investigate the effects and mechanisms of XXMD on neuroprotection subsequent to cerebral ischemia/reperfusion in vivo and in vitro. Neurobehavioral test, TTC staining, HE staining and nissl staining were used to examine the neuroprotective effect of XXMD on cerebral ischemia-reperfusion injury induced by middle cerebral artery occlusion (MCAO) in rats. Additionally, we assessed cell viability and injury with CCK8 and lactate dehydrogenase (LDH) assays. The changes in neuronal ultra-structure were observed after oxygen-glucose deprivation and reoxygenation (OGD/R) by transmission electron microscopy (TEM). Network analysis combined with ultrahighperformance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) predicted the mechanism of XXMD on ischemic stroke injury. Furthermore, the expression of neuroplasticity-related proteins neurofilament 200 (NF200), microtubule-associated protein 2 (MAP2), postsynaptic density protein 95 (PSD95), synaptophysin (SYN), phosphorylated Janus kinase2 (p-JAK2), and phosphorylated signal transduction and activator of transcription 3 (p-STAT3) was evaluated by immunofluorescence staining and western blot analyses. XXMD significantly improved Ethology, infarct area and pathological changes after MCAO and reperfusion, reducing morphological and ultrastructural alterations and decreased cell viability in HT22 cells induced by OGD/R. Network pharmacology showed that 1153 compounds of XXMD were matched. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis demonstrated that XXMD treated ischemia stroke mainly regulating inflammation reaction-related signaling pathways, atherosclerosish-related signaling pathways. Molecular docking results showed that TP53, AKT1, STAT3, and IL6 are closely bound to the corresponding active ingredients. XXMD treatment significantly reversed the above alternations. XXMD or AG490 up-regulated the expression of neuroplasticity-associated proteins, and reduced phosphorylation of JAK2, STAT3 expression following OGD/R. XXMD exerts neuroprotective effects by promoting neural plasticity via regulating the JAK2/STAT3 pathway, indicating a promising alternative therapeutic strategy for ischemic stroke.

Extracellular vesicles of ADSCs inhibit ischemic stroke-induced pyroptosis through Gbp3 regulation: A role for the NLRP3/GSDMD signaling pathway.

Mounting data indicates that extracellular vesicles (EVs) have the potential to improve the injury after a stroke. Pyroptosis is a recently identified kind of programmed cell death that initiates an inflammatory reaction. We aimed to ascertain the therapeutic implications and possible molecular processes of EVs obtained from adipose-derived stem cells (ADSCs) in inhibiting pyroptosis in ischemic stroke. The investigation employed transient middle cerebral artery occlusion (tMCAO) rat model and a BV2 of oxygen-glucose deprivation/reoxygenation (OGD/R) to ascertain ADSCs-EVs implications on inflammation and pyroptosis as assessed by neurological deficit scores, TTC staining, IHC, HE, CCK8, WB, ELISA, and immunofluorescence. RNA-Seq was performed on BV2 cells in the control, OGD/R, and OGD/R + ADSCs-EVs groups. Using sequencing data analysis, in the OGD/R group, we screened the upregulated genes regulated by EVs, overlapped with 74 pyroptosis-related genes, and identified Guanylate-binding protein 2 (Gbp2) and Guanylate-binding protein 3 (Gbp3) as key genes. Following the validation of the sequencing results in vivo and in vitro, Gbp3 was selected for further study. To test its regulatory effects on inflammation and pyroptosis, Gbp3 was knocked down and overexpressed in vitro. The administration of ADSCs-EVs resulted in a significant reduction in neurological involvement scores and reduced infarct volume in rats with tMCAO. They were also protective against BV-2 cells after OGD/R. In vivo and in vitro, ADSCs-EVs inhibited inflammatory response and pyroptosis after stroke. The outcomes of the RNA-Seq data analysis manifested that the protective implications of EVs after stroke are mediated by the modulation of inflammation-related mechanisms. Moreover, treatment with EVs led to a significant reduction in Gbp3 expression in post-ischemic brain tissue and cells. When Gbp3 was knocked down, the expression of inflammatory molecules and proteins linked to pyroptosis had a significant decline. When Gbp3 was overexpressed, the opposite results were obtained. ADSCs-EVs modulate the NLRP3/GSDMD signaling pathway via Gbp3 to attenuate the inflammatory response and reduce pyroptosis that occurs after stroke.

Inhibition of Circ0001679 Alleviates Ischemia/Reperfusion-induced Brain Injury via miR-216/TLR4 Regulatory Axis

Background: Stroke, primarily known as ischemic stroke, is a leading cause of mortality and disability worldwide. Reperfusion after the ischemia stroke resolves is necessary for maintaining the health of brain tissues; however, it also induces inflammation and oxidative stress, resulting in brain injury. This study aimed to investigate the role of circ0001679 in the pathology of I/R (Ischemia/Reperfusion)-induced brain injury and explore its therapeutic potential for I/R injury. Methods: The Oxygen-Glucose Deprivation/Re-oxygenation (OGD/R) model was employed in primary mouse astrocytes, and the Middle Cerebral Artery Occlusion (MCAO) model was established in mice to mimic ischemia-reperfusion-induced injury. Si-circ0001679, anti-miR- 216, and TLR4 ORF-clone were transfected either in cells or mice to study the molecular mechanisms during I/R-induced injury. Inflammation and oxidative stress were monitored after treatment. Results: Upregulated gene expression of circ0001679 was noticed in both OGD/R-treated primary mouse astrocytes and MCAO-induced mouse brain tissue. Silencing circ0001679 reduced cellular damage, inflammation, and oxidative stress induced by OGD/R treatment. Knocking down of circ0001679 alone with either miR-216 inhibition or TLR4 overexpression increased the inflammation response and oxidative stress compared to circ0001679 silencing only. Moreover, inhibition of circ0001679 attenuated brain injury in MCAO-treated mice via reduced infarction, neuronal damage, apoptosis, inflammation, and oxidative stress. Conclusion: This study unveiled a novel regulatory axis of circ0001679-miR-216-TLR4 in I/Rinduced brain injury. Targeting circ0001679 may represent a promising therapeutic strategy for I/R-induced brain injury. result: Upregulated gene expression of circ0001679 was noticed in both OGD/R-treated primary mouse astrocytes and MCAO-induced mouse brain tissue. Silencing circ0001679 reduced cellular damage, inflammation, and oxidative stress induced by OGD/R treatment. Knocking down of circ0001679 alone with either miR-216 inhibition or TLR4 overexpression increased the inflammation response and oxidative stress compared to circ0001679 silencing only. Moreover, inhibition of circ0001679 attenuated brain injury in MCAO-treated mice via reduced infarction, neuronal damage, apoptosis, inflammation, and oxidative stress.

Overexpression of Growth Differentiation Factor 15 Reduces Neuronal Cell Damage Induced by Oxygen-Glucose Deprivation/Reoxygenation via Inhibiting Endoplasmic Reticulum Stress-Mediated Ferroptosis.

Growth differentiation factor 15 (GDF15) can be induced under various stress conditions. This study aimed to explore the role of GDF15 in oxygen-glucose deprivation/reoxygenation (OGD/R)-induced HT22 cells. OGD/R was employed to induce the HT22 cell model, and GDF15 expression was upregulated via transfection. Subsequently, the effects on inflammatory factors, oxidative stress markers, apoptosis-related proteins, and ferroptosis markers were detected. Relevant indicators were evaluated using techniques such as ELISA, probes, flow cytometry, and western blotting. Furthermore, changes in these phenotypes under the influence of the endoplasmic reticulum (ER) stress agonist tunicamycin (TM) were evaluated. The result showed that GDF15 was significantly up-regulated in OGD/R-treated HT22 cells. Overexpression of GDF15 significantly reduced the levels of inflammatory factors tumor necrosis factor-α, IL (interleukin)-1β, and IL-6, inhibited the production of reactive oxygen species and MDA, and improved activity of superoxide dismutase and GSH-Px. Flow cytometry and western blotting results showed that GDF15 overexpression significantly reduced cell apoptosis, reduced caspase3 activity, and regulated the expression of Bcl2 and Bax. In addition, overexpression of GDF15 reduces the levels of ferroptosis markers by inhibiting ER stress. ER stress inducer TM can reverse the protective effects of GDF15 overexpression and promote inflammation, oxidative stress, and apoptosis. This study shows that overexpression of GDF15 reduces OGD/R-induced HT22 cell damage, and ER stress-mediated ferroptosis is included in the regulatory mechanisms. This provides a theoretical basis for GDF15 as a new target for the treatment of cerebral ischemia-reperfusion injury.

Nek6 regulates autophagy through the mTOR signaling pathway to alleviate cerebral ischemia–reperfusion injury

ObjectiveCerebral ischemia–reperfusion injury (CIRI) is a major obstacle to neurological recovery after clinical treatment of ischemic stroke. The aim of this study was to investigate the molecular mechanism of Nek6 alleviating CIRI through autophagy after cerebral ischemia.Materials and methodsA mouse model of CIRI was constructed by middle cerebral artery occlusion (MCAO). TUNEL staining was used to observe the apoptosis of neuronal cells. The oxygen glucose deprivation/reoxygenation (OGD/R) model was established by hypoxia and reoxygenation. The cell apoptosis and activity was detected. Western blot was performed to detect the expression of autophagy-related proteins, protein kinase B (Akt)/mammalian target of rapamycin (mTOR) and adenosine 5’-monophosphate-activated protein kinase (AMPK)/mTOR signaling pathway-related proteins. Cellular autophagy flux was observed by fluorometric method. NIMA-related kinase 6 (Nek6) mRNA stability was detected by actinomycin D treatment. Methylation RNA immunoprecipitation technique was used to detect Nek6 methylation level.ResultsNek6 expression was increased in both MCAO and OGD/R models. Overexpression of Nek6 in OGD/R inhibited apoptosis, decreased LC3II and Beclin-1 expression, increased p62 expression, and occurred lysosome dysfunction. Interference with Nek6 has opposite results. Nek6 overexpression promoted p-Akt and p-mTOR protein expressions, inhibited p-AMPK and p-UNC-51-like kinase 1 protein expressions and cell apoptosis, while LY294002, Rapamycin or RSVA405 treatment reversed this effect. Abnormal methyltransferase·like protein 3 (METTL3) expression in CIRI enhanced m6A modification and promoted Nek6 expression level.ConclusionThis study confirmed that Nek6 regulates autophagy and alleviates CIRI through the mTOR signaling pathway, which provides a novel therapeutic strategy for patients with ischemic stroke in the future.