Search Results (311)

Background/Objectives: Retinal ischemia–reperfusion (I/R) injury is a common mechanism in glaucoma, diabetic retinopathy, and retinal vein occlusion, leading to progressive loss of retinal ganglion cells (RGCs). This study investigates the regulatory role of miR-21-5p and its interaction with Signal Transducer and Activator of Transcription 3 (STAT3) in retinal I/R injury. Methods: An acute intraocular hypertension (AIH) rat model was used to induce retinal I/R. The interaction between miR-21-5p and STAT3 was examined by dual-luciferase reporter assays. miR-21-5p and STAT3 expression were quantified by qRT-PCR and Western blotting. Retinal morphology, microglial polarization, and RGC survival were assessed by H&E staining and immunofluorescence. In vitro, microglia and RGCs were subjected to oxygen–glucose deprivation/reperfusion (OGD/R), and microglial-conditioned media (MCM) were applied to RGCs. Results: (1) miR-21-5p ameliorated AIH-induced retinal damage in vivo. (2) Overexpression of miR-21-5p inhibits M1 polarization of RM cultured in vitro. (3) MCM from miR-21-5p-overexpressing microglia attenuated OGD/R-induced RGC death. (4) miR-21-5p downregulates STAT3 expression to inhibit RM M1 polarization. (5) miR-21-5p down-regulation of STAT3 levels inhibits M1 polarization and reduces apoptosis of RGCs in retinal microglia of AIH rats. Conclusions: miR-21-5p alleviates retinal I/R injury by restraining microglial M1 polarization through direct repression of STAT3, thereby promoting RGC survival. These findings identify the miR-21-5p/STAT3 axis as a potential therapeutic target for ischemic retinal diseases. Full article

Cerebral ischemia/reperfusion (I/R) injury remains a significant contributor to adult neurological morbidity, primarily due to exacerbated neuroinflammation and cell apoptosis. These processes amplify brain damage through the release of various pro-inflammatory cytokines and pro-apoptotic mediators. Although long non-coding RNAs (lncRNAs) are increasingly recognized for their involvement in regulating diverse biological pathways, their precise role in cerebral I/R injury has not been fully elucidated. In the current study, transcriptomic profiling was conducted using a rat model of focal cerebral I/R, leading to the identification of lncRNA-1810026B05Rik—also referred to as CHASERR—as a novel lncRNA responsive to ischemic conditions. The elevated expression of this lncRNA was observed in mouse brain tissues subjected to middle cerebral artery occlusion followed by reperfusion (MCAO/R), as well as in primary cortical neurons derived from rats exposed to oxygen-glucose deprivation and subsequent reoxygenation (OGD/R). The results suggested that lncRNA-1810026B05RiK mediates the activation of the nuclear factor-kappaB (NF-κB) signaling pathway by physically binding to NF-kappa-B inhibitor alpha (IκBα) and promoting its phosphorylation, thus leading to neuroinflammation and neuronal apoptosis during cerebral ischemia/reperfusion. In addition, lncRNA-1810026B05Rik knockdown acts as an NF-κB inhibitor in the OGD/R and MCAO/R pathological processes, suggesting that lncRNA-1810026B05Rik downregulation exerts a protective effect on cerebral I/R injury. In summary, the lncRNA-1810026B05Rik has been identified as a critical regulator of neuronal apoptosis and inflammation through the activation of the NF-κB signaling cascade. This discovery uncovers a previously unrecognized role of 1810026B05Rik in the molecular mechanisms underlying ischemic stroke, offering valuable insights into disease pathology. Moreover, its involvement highlights its potential as a novel therapeutic target, paving the way for innovative treatment strategies for stroke patients. Full article

Human amniotic epithelial cell-derived exosomes (hAECs-Exos) are nanoscale extracellular vesicles with neuroprotective, regenerative, and anti-inflammatory properties, presenting a promising cell-free therapeutic approach for ischemic stroke. This study investigated the protective effects of hAECs-Exos against ischemic injury and explored the underlying molecular mechanisms. An optimized oxygen-glucose deprivation/reoxygenation (OGD/R) model was established in murine hippocampal HT22 neurons and BV2 microglial cells to simulate ischemic conditions. hAECs-Exos were successfully isolated and characterized via transmission electron microscopy, nanoparticle tracking analysis, and Western blotting. Confocal microscopy confirmed efficient exosome uptake by both cell types. Functional analyses revealed that hAECs-Exos significantly improved cell viability, suppressed pro-inflammatory cytokine release, alleviated oxidative stress, and modulated apoptosis-related proteins. RNA sequencing identified Forkhead box protein M1 (FoxM1) as a significantly upregulated transcription factor following hAECs-Exos treatment. Further experiments demonstrated that knockdown of FoxM1 in hAECs abolished the beneficial effects of exosomes on the viability of HT22 and BV2 cells and on the suppression of inflammation, oxidative stress, and apoptosis. These findings indicate that hAECs-Exos confer neuroprotection through FoxM1-dependent mechanisms. Together, our results highlight the therapeutic potential of hAECs-Exos as a safe, effective, and clinically translatable strategy for ischemic stroke treatment, warranting future validation in vivo and rescue experiments to fully elucidate FoxM1’s causal role. Full article

Cerebral ischemia/reperfusion (I/R) injury is a devastating neurological disorder with limited treatment options. Emerging evidence suggests that the N6-methyladenosine (m6A) modification and its regulatory factors play pivotal roles in the pathophysiology of I/R. This study aimed to elucidate the function of METTL3-mediated m6A modification of the long non-coding RNA (lncRNA) AU020206 in ferroptosis during cerebral I/R injury and to identify potential molecular targets for neuroprotection. A murine model of middle cerebral artery occlusion/reperfusion (MCAO/R) and N2a cells subjected to oxygen–glucose deprivation/reoxygenation (OGD/R) were established to assess m6A levels and ferroptosis-related changes. Effects of METTL3 overexpression and lncRNA-AU020206 silencing on neuronal apoptosis, inflammation, and ferroptosis were investigated in vitro and in vivo. The interaction between lncRNA-AU020206 and YTHDC2 and the resulting regulation of SLC7A11 mRNA stability and GPX4 expression were evaluated using molecular and biochemical assays. Both MCAO/R mice and OGD/R-treated N2a cells exhibited decreased m6A levels and upregulation of lncRNA-AU020206 accompanied by enhanced ferroptosis. METTL3 overexpression increased the m6A modification of AU020206, promoting its degradation and attenuating neuronal injury, whereas silencing AU020206 or overexpressing YTHDC2 decreased SLC7A11 mRNA stability and enhanced ferroptosis. Restoring the expression of SLC7A11/GPX4 can enhance cell viability, alleviate neuronal apoptosis, and reduce Fe²⁺ overload. Disruption of the METTL3–AU020206–YTHDC2 axis abolished these neuroprotective effects. METTL3-mediated m6A modification of lncRNA-AU020206 restrained ferroptosis and neuronal injury in cerebral I/R by maintaining the stability of the SLC7A11/GPX4 axis via interactions with YTHDC2. Targeting this epitranscriptomic signalling pathway may represent a promising therapeutic strategy for the treatment of ischemic stroke and related neurological disorders. Full article

Ischemia/reperfusion (I/R) injury following stroke results in increased neuronal cell death due to mitochondrial hyperactivity. Ischemia results in loss of regulatory phosphorylations on cytochrome c oxidase (COX) and cytochrome c of the electron transport chain (ETC), priming COX for hyperactivity. During reperfusion, the ETC operates at maximal speed, resulting in hyperpolarization of the mitochondrial membrane potential (ΔΨ_m) and reactive oxygen species (ROS) production. We have shown that COX-inhibitory near-infrared light (IRL) provides neuroprotection in small and large animal models of brain I/R injury. IRL therapy is non-invasive and non-pharmacological and does not rely on blood flow. We identified specific wavelengths of IRL, 750 and 950 nm, that inhibit COX activity. To model the mitochondrial effects following neuronal I/R, SH-SY5Y cells underwent oxygen–glucose deprivation/reoxygenation (OGD/R) ± IRL applied at the time of reoxygenation. Untreated cells exhibited ΔΨ_m hyperpolarization, whereas IRL treated cells showed no significant difference compared to control. IRL treatment suppressed ROS production, decreased the level of cell death, and reduced the time to normalize mitochondrial activity to baseline levels from 4–5 to 2.5 h of reperfusion time. We show that IRL treatment is protective by limiting ΔΨ_m hyperpolarization and ROS production, and by speeding up cellular recovery. Full article

Islet transplantation can improve glycemic control in a subset of patients with type 1 diabetes mellitus (T1DM). This therapeutic approach is often limited by scarcity of adequate donor islets and an insufficient revascularization capacity of grafted islets. Recent findings reveal that sex is an important determinant for the outcome of islet transplantation. However, it is still unknown how the biological sex of islet donors and recipients affects the revascularization of the grafts during the initial ischemic post-transplantation phase. In this study, we observed in a mouse dorsal skinfold chamber model a higher revascularization capacity of female islets transplanted in female or male recipient mice when compared to male islets transplanted in female or male recipients. To mimic the ischemic in vivo conditions ex vivo, we subjected isolated female and male islets to oxygen-glucose deprivation. Under these conditions female islets expressed and secreted significantly more glucagon (GCG). By a panel of functional angiogenesis assays, we could further demonstrate that GCG exhibits a strong pro-angiogenic function. This effect was pronounced in blood vessels as well as endothelial cells and pericytes of female origin due to a higher expression of GCG receptor. Taken together, these results not only confirm the clinical observation that transplantation of female islets improves the outcome of islet transplantation but also indicate that this is mediated by an accelerated GCG-driven islet engraftment. Full article

Background: Post-myocardial infarction (MI) heart failure (HF) is characterized by myocardial energy metabolism disorder, with excessive glycolysis playing a key role in its progression. Silybin (SIL), a flavonoid derived from Silybum marianum, has demonstrated hepatoprotective and metabolic regulatory effects. However, the role of this flavonoid in ameliorating post-myocardial infarction heart failure (post-MI HF) by modulating energy metabolism remains unclear. Methods: This study employed an oxygen–glucose deprivation (OGD) model to induce myocardial cell injury in vitro, with YC-1 treatment used to inhibit hypoxia-inducible factor-1α (HIF-1α) for mechanistic validation. A myocardial infarction-induced HF mouse model was used for in vivo experiments. Results: In vitro, SIL enhanced cell viability, increased ATP levels, and decreased lactate production and reactive oxygen species (ROS) accumulation in OGD-treated myocardial cells. SIL downregulated the mRNA and protein expression of HIF-1α, 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), glucose transporter 1 (GLUT1), and lactate dehydrogenase A (LDHA) while inhibiting HIF-1α nuclear translocation. Furthermore, SIL suppressed glycolytic proteins (PFKFB3, GLUT1, and LDHA) in a manner comparable to the HIF-1α inhibitor YC-1. This confirms that SIL’s inhibition of glycolysis is HIF-1α-dependent. In vivo, SIL treatment improved cardiac function parameters (LVEF and LVFS) and attenuated left ventricular remodeling (LVID;d and LVID;s) in post-MI HF mice. Additionally, myocardial fibrosis markers were significantly reduced, accompanied by a decrease in the myocardial mRNA and protein expression of glycolytic proteins, including HIF-1α, PFKFB3, GLUT1, and LDHA. Conclusions: Silybin effectively ameliorates post-myocardial infarction heart failure through the HIF-1α-mediated regulation of glycolysis, leading to improved myocardial energy metabolism and enhanced cardiac function. Full article

A new trinor-sesterterpenoid penitalarin D (1), with a 3,6-dioxabicyclo[3.1.0]hexane moiety, as well as two known compounds, penitalarin C (2) and nafuredin A (3), were obtained from the mangrove sediment-derived Talaromyces sp. SCSIO 41412. Their structures were determined by detailed NMR, MS spectroscopic analyses, and ECD calculations. Penitalarin D (1) and nafuredin A (3) showed toxicity or no toxicity against HepG2 cells at a concentration of 200 μM. The transcriptome sequencing and bioinformatics analysis revealed that 3 could be effective by regulating ferroptosis pathways in HepG2 cells, which was subsequently validated by RT-qPCR, demonstrating significant upregulation of ferroptosis-related genes. Pre-treatment with 3 could mitigate hypoxia-reoxygenation-induced damage in the oxygen glucose deprivation/reperfusion (OGD/R) cell model. Given the structural similarity of compounds 1, 2, and 3, we also screened compounds 1 and 2 in an AML12 OGD/R model. As no significant activity was observed, compound 3 was selected for subsequent in vivo studies. Subsequently, in vivo experiments demonstrated that 3 could significantly decrease pro-inflammatory cytokines and display the hepatoprotective effects against hepatic ischemia-reperfusion injury (HIRI). These findings identified nafuredin A (3) as a promising hepatoprotective agent for new drug development. Full article

Isoliquiritigenin (ISL) is a type of chalcone that widely exists in medicinal plants of the Leguminosae family and exhibits a remarkable anti-ischemic stroke (IS) effect. However, the anti-IS mechanisms of ISL remain to be systematically elucidated. In this study, network pharmacology was used to predict potential targets related to the anti-IS effect of ISL. The binding ability of ISL to potential core targets was further analyzed by molecular docking and molecular dynamics (MD) simulations. By establishing an oxygen–glucose deprivation/reoxygenation (OGD/R)-induced HT22 cell model, the anti-IS mechanisms of ISL were investigated via RT-qPCR and Western Blot (WB). As a result, network pharmacology analysis revealed that APP, ESR1, MAO-A, PTGS2, and EGFR may be potential core targets of ISL for anti-IS treatment. Molecular docking and molecular dynamics simulation results revealed that ISL can stably bind to the five potential core targets and form stable complex systems with them. The results of the cell experiments revealed a significant anti-IS effect of ISL. Additionally, mRNA and protein expression levels of APP, MAO-A and PTGS2 or ESR1 in the ISL treatment group were significantly lower or higher than those in the OGD/R group In conclusion, ISL may improve IS by regulating the protein expression levels of APP, ESR1, MAO-A, and PTGS2. Full article

Cardiopulmonary bypass (CPB) is associated with significant neurological complications, yet the mechanisms underlying brain injury remain unclear. This study investigated the role of interleukin-17A (IL-17A) in exacerbating CPB-induced neuronal apoptosis and identified vulnerable brain regions. Utilizing a rat CPB model and an oxygen–glucose deprivation/reoxygenation (OGD/R) cellular model, we demonstrated that IL-17A levels were markedly elevated in the hippocampus post-CPB, correlating with endoplasmic reticulum stress (ERS)-mediated apoptosis. Transcriptomic analysis revealed the enrichment of IL-17 signaling and apoptosis-related pathways. IL-17A-Neutralizing monoclonal antibody (mAb) and the ERS inhibitor 4-phenylbutyric acid (4-PBA) significantly attenuated neurological deficits and hippocampal neuronal damage. Mechanistically, IL-17A activated the Act1-IRE1-JNK1 axis, wherein heat shock protein 90 (Hsp90) competitively regulated Act1-IRE1 interactions. Co-immunoprecipitation confirmed the enhanced Hsp90-Act1 binding post-CPB, promoting IRE1 phosphorylation and downstream caspase-12 activation. In vitro, IL-17A exacerbated OGD/R-induced apoptosis via IRE1-JNK1 signaling, reversible by IRE1 inhibition. These findings identify the hippocampus as a key vulnerable region and delineate a novel IL-17A/Act1-IRE1-JNK1 pathway driving ERS-dependent apoptosis. Targeting IL-17A or Hsp90-mediated chaperone switching represents a promising therapeutic strategy for CPB-associated neuroprotection. This study provides critical insights into the molecular crosstalk between systemic inflammation and neuronal stress responses during cardiac surgery. Full article

Neuroinflammation is the major contributor to the pathology of neonatal hypoxic–ischemic (HI) brain injury. Our previous studies have demonstrated that microRNA210 (miR210) inhibition with antisense locked nucleic acid (LNA) inhibitor mitigates neuroinflammation and provides neuroprotection after neonatal HI insult. However, the underlying mechanisms remain elusive. In the present study, using miR210 knockout (KO) mice and microglial cultures, we tested the hypothesis that miR210 promotes microglial activation and neuroinflammation through suppressing mitochondrial function in microglia after HI. Neonatal HI brain injury was conducted on postnatal day 9 (P9) wild-type (WT) and miR210 knockout (KO) mouse pups. We found that miR210 KO significantly reduced brain infarct size at 48 h and improved long-term locomotor functions assessed by an open field test three weeks after HI. Moreover, miR210 KO mice exhibited reduced IL1β levels, microglia activation and immune cell infiltration after HI. In addition, in vitro studies of microglia exposed to oxygen–glucose deprivation (OGD) revealed that miR210 inhibition with LNA reduced OGD-induced expression of Il1b and rescued OGD-mediated downregulation of mitochondrial iron–sulfur cluster assembly enzyme (ISCU) and mitochondrial oxidative phosphorylation activity. To validate the link between miR210 and microglia activation, isolated primary murine microglia were transfected with miR210 mimic or negative control. The results showed that miR210 mimic downregulated the expression of mitochondrial ISCU protein abundance and induced the expression of proinflammatory cytokines similar to the effect observed with ISCU silencing RNA. In summary, our results suggest that miR210 is a key regulator of microglial proinflammatory activation through reprogramming mitochondrial function in neonatal HI brain injury. Full article

Ischemic stroke is a serious disease that frequently occurs in the elderly and is characterized by a complex pathophysiology and a limited number of effective therapeutic agents. Salvianolic acid A (SAL-A) is a natural product derived from the rhizome of Salvia miltiorrhiza, which possesses diverse pharmacological activities. This study aims to investigate the effect and mechanisms of SAL-A in inhibiting ferroptosis to improve ischemic stroke. Brain injury, oxidative stress and ferroptosis-related analysis were performed to evaluate the effect of SAL-A on ischemic stroke in photochemical induction of stroke (PTS) in mice. Lipid peroxidation levels, antioxidant protein levels, tissue iron content, nuclear factor erythroid 2-related factor 2 (Nrf2), and mitochondrial morphology changes were detected to explore its mechanism. SAL-A significantly attenuated brain injury, reduced malondialdehyde (MDA) and long-chain acyl-CoA synthase 4 (ACSL4) levels. In addition, SAL-A also amplified the antioxidative properties of glutathione (GSH) when under glutathione peroxidase 4 (GPX4), and the reduction in ferrous ion levels. In vitro, brain microvascular endothelial cells (b.End.3) exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) were used to investigate whether the anti-stroke mechanism of SAL-A is related to Nrf2. Following OGD/R, ML385 (Nrf2 inhibitor) prevents SAL-A from inhibiting oxidative stress, ferroptosis, and mitochondrial dysfunction in b.End.3 cells. In conclusion, SAL-A inhibits ferroptosis to ameliorate ischemic brain injury, and this effect is mediated through Nrf2. Full article

Brain ischemia is a severe condition caused by reduced cerebral blood flow, leading to the disruption of ion gradients in brain tissue. This imbalance triggers spreading depolarizations, which are waves of neuronal and glial depolarization propagating through the gray matter. Microelectrode arrays (MEAs) are essential for real-time monitoring of these electrophysiological processes both in vivo and in vitro, but their sensitivity and signal quality are critical for accurate detection of extracellular brain activity. In this study, we evaluate the performance of a flexible microelectrode array based on gold-coated zinc oxide nanorods (ZnO NRs), referred to as nano-fMEA, specifically for high-fidelity electrophysiological recording under pathological conditions. Acute mouse brain slices were tested under two ischemic models: oxygen–glucose deprivation (OGD) and hyperkalemia. The nano-fMEA demonstrated significant improvements in event detection rates and in capturing subtle fluctuations in neural signals compared to flat fMEAs. This enhanced performance is primarily attributed to an optimized electrode–tissue interface that reduces impedance and improves charge transfer. These features enabled the nano-fMEA to detect weak or transient electrophysiological events more effectively, making it a valuable platform for investigating neural dynamics during metabolic stress. Overall, the results underscore the promise of ZnO NRs in advancing electrophysiological tools for neuroscience research. Full article

Background: Astrocytes are not only structural cells but also play a pivotal role in neurogenesis and neuroprotection by secreting a variety of neurotrophic factors that support neuronal survival, growth, and repair. This study investigates the time-dependent responses of primary rat cortical astrocytes to oxygen–glucose deprivation (OGD) and evaluates the neuroprotective potential of astrocyte-conditioned medium (ACM). Methods: Primary rat cortical astrocytes and neurons were obtained from postnatal Sprague Dawley rat pups (P1–3) and embryos (E17–18), respectively. Astrocytes exposed to 6, 24, and 48 h of OGD (0.3% O₂) were assessed for viability, metabolic function, hypoxia-inducible factor 1 and its downstream genes expression. Results: While 6 h OGD upregulated protective genes such as Vegf, Glut1, and Pfkfb3 without cell loss, prolonged OGD, e.g., 24 or 48 h, led to significant astrocyte death and stress responses, including elevated LDH release, reduced mitochondrial activity, and increased expression of pro-apoptotic marker Bnip3. ACM from 6 h OGD-treated astrocytes significantly enhanced neuronal survival following 6 h OGD and 24 h reperfusion, preserving dendritic architecture, improving mitochondrial function, and reducing cell death. This protective effect was not observed with ACM from 24 h OGD astrocytes. Furthermore, 6 h OGD-ACM induced autophagy in neurons, as indicated by elevated LC3b-II and decreased p62 levels, suggesting autophagy as a key mechanism in ACM-mediated neuroprotection. Conclusions: These findings demonstrate that astrocytes exhibit adaptive, time-sensitive responses to ischemic stress and secrete soluble factors that can confer neuroprotection. This study highlights the therapeutic potential of targeting astrocyte-mediated signalling pathways to enhance neuronal survival following ischemic stroke. Full article

Aim of the study: Traditional Chinese herbs have a unique therapeutic effect on stroke and numerous successful clinical cases. However, these clinical cases are highly dispersed, creating challenges for translational research. This study employs a new paradigm to identify treatment patterns and the active compound interactions contained within these clinical cases, with experimental validation after target screening. Methods and Materials: Stroke-related targets were identified through GEO, DisGeNET, and Genecards. Active ingredients were extracted from BATMAN-TCM 2.0. All herbs and diseases were confirmed by the Pharmacopoeia of the People’s Republic of China (2020 edition) and Medical Subject Heading (MeSH). All networks in this study were constructed by Cytoscape, and data analysis was done by Python. All formulations and herbs were retrieved from the literature review. For the molecular docking process, Autodock was applied as the docking platform, and all the protein structures were downloaded from PDB. For experimental validation after target screening, HT22 cells were incubated with glucose-free DMEM and placed in an anaerobic chamber for 2 h. Subsequently, HT22 cells were reoxygenated for 24 h. Estrogen Receptor 1 (ESR1) protein levels were measured in vitro. Results: seven materials, including Angelicae Sinensis Radix, Pheretima, Chuanxiong Rhizoma, Persicae Semen, Astragali Radix, Carthami Flos, and Radix Paeoniae Rubra, were identified as the core herbs for the treatment of stroke. The targets of the stroke mechanism were screened, and the herbs-compound-target network was constructed. Among them, paeoniflorin (PF) was identified as the core active compound, and its interaction with ESR1 was verified by molecular docking as the key interaction for the treatment of stroke. In vitro experiments showed that PF inhibited cell apoptosis under hypoxia by increasing the expression of ESR1 compared with the oxygen-glucose deprivation-reperfusion (OGD/R) model group. Western showed that PF (100 μM, 200 μM) can significantly increase the decreased ESR1 protein level caused by the OGD/R model. Conclusions: seven key herbs were screened. Further bioinformatics and network pharmacology studies suggested that PF is expected to become a new active compound for the treatment of stroke. In vitro validation further demonstrated that PF enhanced neuronal survival and ESR1 expression under ischemic conditions, supporting its therapeutic candidacy. Full article