Cell Death Mechanisms in Cerebral Ischemia-Reperfusion Injury

Ursolic acid improves necroptosis via STAT3 signaling in intestinal ischemia/reperfusion injury

Intestinal ischemia/reperfusion injury (IRI) poses a serious threat to human survival and quality of life with high mortality and morbidity rates. The current absence of effective treatments for intestinal IRI highlights the urgent need to identify new therapeutic targets. Ursolic acid (UA), a pentacyclic triterpene natural compound, has been shown to possess various pharmacological properties including intestinal protection. However, its potential protective efficacy on intestinal IRI remains elusive. This study aimed to investigate the effect of UA on intestinal IRI and explore the underlying mechanisms. To achieve this, we utilized network pharmacology to analyze the mechanism of UA in intestinal IRI and assessed UA's effects on intestinal IRI using a mouse model of superior mesenteric artery occlusion/reperfusion and an in vitro model of oxygen-glucose deprivation and reperfusion-induced IEC-6 cells. Our results demonstrated that UA improved necroptosis through the RIP1/RIP3/MLKL pathway, reduced necroinflammation via the HMGB1/TLR4/NF-κB pathway, attenuated morphological damage, and enhanced intestinal barrier function. Furthermore, UA pretreatment downregulated the phosphorylation level of signal transducer and activator of transcription 3 (STAT3). The effects of UA were attenuated by the STAT3 agonist Colivelin. In conclusion, our study suggests that UA can improve intestinal IRI by inhibiting necroptosis in enterocytes via the suppression of STAT3 activation. These results provide a theoretical basis for UA treatment of intestinal IRI and related clinical diseases.

B. glomerulata promotes neuroprotection against ischemic stroke by inhibiting apoptosis through the activation of PI3K/AKT/mTOR pathway

BACKGROUND

Brassaiopsis glomerulata (Blum) Regel (B.glomerulata) is recognized as a traditional Chinese medicine (TCM) primarily used for promoting blood circulation and removing stasis. It is frequently utilized in the treatment of injuries resulting from falls and bumps.

PURPOSE

Despite its effective use in clinical treatment for ischemic stroke (IS), there are currently no reports on its composition and mechanism of action, which affects its promotion. The study investigated the chemical components and molecular mechanisms of B.glomerulata, with the following components: UPLC-Q-TOF-MS, network pharmacology Analysis and experimental verification in vivo and vitro.

METHODS

The effect of B.glomerulata on interfering with ischemic stroke was assessed on MCAO/R rats and ORD cell model. Then the compositional analysis was conducted using UPLC-Q-TOF-MS. Furthermore, network pharmacology and molecular docking techniques were explored to identify potential targets and pathways. The predicted mechanisms of action were ultimately confirmed by immunohistochemistry and protein blotting.

RESULTS

B. glomerulata exhibited neuroprotective effects in MCAO/R rats by reductions in hippocampal and cortical neuronal damage, brain infarction, and cerebral edema. Both in vivo and in vitro experiments demonstrated that it decreased ROS and MDA levels, increased SOD and GSH levels, thereby inhibiting oxidative stress. Moreover, the improvements in neuronal morphology and the modulation of Nissl bodies suggested a potential mechanism underlying its neuroprotective action. Additionally, B.glomerulata exhibited concentration-dependent reductions in Bax and Caspase-3 expressions, along with increases in GFAP, Bcl2/Bax ratio, p-PI3K, p-AKT, and p-mTOR levels.

CONCLUSION

B.glomerulata exhibited neuroprotective effects against cerebral ischemia-reperfusion injury both in vivo and in vitro. It prevented oxidative stress damage and inhibited apoptosis of ischemic stroke through the PI3K/AKT/mTOR pathway.

Naoxintong capsule accelerates mitophagy in cerebral ischemia-reperfusion injury via TP53/PINK1/PRKN pathway based on network pharmacology analysis and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

The incidence and mortality of cerebrovascular diseases are increasing year by year. Cerebral ischemia-reperfusion injury (CIRI) is common in patients with ischemic stroke. Naoxintong (NXT) is composed of a variety of Chinese medicines and has the ability to treat CIRI.

AIM OF THE STUDY

The aim of this study is to investigate whether NXT regulates mitophagy in CIRI based on network pharmacology analysis and experimental validation.

MATERIALS AND METHODS

Oxygen and glucose deprivation/re-oxygenation (OGD/R, 2/22 h) model of PC12 cells and transient middle cerebral artery occlusion (tMCAO, 2/22 h) model of rats were established. Pharmacodynamic indicators include neurological deficit score, 2,3,5-triphenyte-trazoliumchloride (TTC) staining, hematoxylin-eosin (HE) staining and cell viability. Network pharmacology was used to predict pharmacological mechanisms. Pharmacological mechanism indexes include transmission electron microscopy (TEM), drug affinity responsive target stability (DARTS), cellular thermal shift assay (CETSA), immunohistochemistry (IHC), western blot (WB) and immunofluorescence (IF). Kevetrin (an agonists of p53) and pifithrin-α (an inhibitor of p53) used to detect the key role of p53 in mitophagy of NXT.

RESULTS

NXT (1% serum containing NXT and 110 mg/kg) improved the damage of OGD/R PC12 cells and tMCAO rats, and this protective effect was related to the anti-oxidation and ability to promote mitophagy of NXT. NXT and pifithrin-α increased the expression of promoting-mitophagy targets (PINK1, PRKN and LC3B) and inhibited the expression of inhibiting-mitophagy targets (p52) via restraining p53, and finally accelerated mitophagy caused by CIRI.

CONCLUSION

This study demonstrates that NXT promotes mitophagy in CIRI through restraining p53 and promoting PINK1/PRKN in vivo and in vitro.

N-ethylmaleimide-sensitive factor elicits a neuroprotection against ischemic neuronal injury by restoring autophagic/lysosomal dysfunction

Autophagosome-lysosome fusion defects play a critical role in driving autolysosomal dysfunction, leading to autophagic/lysosomal impairment in neurons following ischemic stroke. However, the mechanisms hindering autophagosome-lysosome fusion remain unclear. Soluble N-ethylmaleimide-sensitive factor (NSF) is an essential ATPase to reactivate STX17 and VAMP8, which are the paired molecules to mediate fusion between autophagosomes and lysosomes. However, NSF is frequently inactivated to inhibit the reactivation of STX17 and VAMP8 in ischemic neurons. Herein, we investigated whether autophagosome-lysosome fusion could be facilitated to alleviate autophagic/lysosomal impairment in ischemic neurons by over-expressing NSF. Rat model of middle cerebral artery occlusion (MCAO) and HT22 neuron ischemia model of oxygen-glucose deprivation (OGD) were prepared, respectively. The results demonstrated that NSF activity was significantly suppressed, accompanied by reduced expressions of STX17 and VAMP8 in penumbral neurons 48 h post-MCAO and in HT22 neurons 2 h post-OGD. Moreover, the attenuated autolysosome formation accompanied by autophagic/lysosomal dysfunction was observed. Thereafter, NSF activity in HT22 neurons was altered by over-expression and siRNA knockdown, respectively. After transfection with recombinant NSF-overexpressing lentiviruses, both STX17 and VAMP8 expressions were concurrently elevated to boost autophagosome-lysosome fusion, as shown by enhanced immunofluorescence intensity co-staining with LC3 and LAMP-1. Consequently, the OGD-created autophagic/lysosomal dysfunction was prominently ameliorated, as reflected by augmented autolysosomal functions and decreased autophagic substrates. By contrast, NSF knockdown conversely aggravated the autophagic/lysosomal impairment, and thereby exacerbated neurological damage. Our study indicates that NSF over-expression induces neuroprotection against ischemic neuronal injury by restoring autophagic/lysosomal dysfunction via the facilitation of autophagosome-lysosome fusion. Over-expression of NSF promotes fusion by reactivating STX17 and VAMP8. Black arrows represent the pathological process after cerebral ischemia, green arrows represent the mechanism of remission after NSF over-expression, and red arrows represent the effect on the pathological process after NSF knockdown.

Ginsenoside Rg1 ameliorates cerebral ischemia-reperfusion injury by regulating Pink1/ Parkin-mediated mitochondrial autophagy and inhibiting microglia NLRP3 activation

OBJECTIVE

This study aimed to further elucidate the mechanism of ginsenoside Rg1 in the treatment of cerebral ischemia-reperfusion.

METHODS

In this study, we observed the apoptosis of RM cells (microglia) after oxygen-glucose deprivation/reoxygenation (OGD/R) modeling before and after Rg1 administration, changes in mitochondrial membrane potential, changes in the content of Reactive oxygen species (ROS) and inflammatory vesicles NLR Family Pyrin Domain Containing 3 (NLRP3), and the expression levels of autophagy-related proteins, inflammatory factors, and apoptosis proteins. We further examined the pathomorphological changes in brain tissue, neuronal damage, changes in mitochondrial morphology and mitochondrial structure, and the autophagy-related proteins, inflammatory factors, and apoptosis proteins expression levels in CI/RI rats before and after administration of Rg1 in vivo experiments.

RESULTS

In vitro experiments showed that Rg1 induced mitochondrial autophagy, decreased mitochondrial membrane potential, and reduced ROS content thereby inhibiting NLRP3 activation, decreasing secretion of inflammatory factors and RM cell apoptosis by regulating the PTEN induced putative kinase 1(Pink1) /Parkin signaling pathway. In vivo experiments showed that Rg1 induced mitochondrial autophagy, inhibited NLRP3 activation, improved inflammatory response, and reduced apoptosis by regulating the Pink1/Parkin signaling pathway, and Rg1 significantly reduced the area of cerebral infarcts, improved the pathological state of brain tissue, and attenuated the neuronal damage, thus improving cerebral ischemia/reperfusion injury in rats.

CONCLUSION

Our results suggest that ginsenoside Rg1 can ameliorate cerebral ischemia-reperfusion injury by modulating Pink1/ Parkin-mediated mitochondrial autophagy in microglia and inhibiting microglial NLRP3 activation.

Therapeutic potential of fucoidan in central nervous system disorders: A systematic review

Central nervous system (CNS) disorders have a complicated pathogenesis, and to date, no single mechanism can fully explain them. Most drugs used for CNS disorders primarily aim to manage symptoms and delay disease progression, and none have demonstrated any pathological reversal. Fucoidan is a safe, sulfated polysaccharide from seaweed that exhibits multiple pharmacological effects, and it is anticipated to be a novel treatment for CNS disorders. To assess the possible clinical uses of fucoidan, this review aims to provide an overview of its neuroprotective mechanism in both in vivo and in vitro CNS disease models, as well as its pharmacokinetics and safety. We included 39 articles on the pharmacology of fucoidan in CNS disorders. In vitro and in vivo experiments demonstrate that fucoidan has important roles in regulating lipid metabolism, enhancing the cholinergic system, maintaining the functional integrity of the blood-brain barrier and mitochondria, inhibiting inflammation, and attenuating oxidative stress and apoptosis, highlighting its potential for CNS disease treatment. Fucoidan has a protective effect against CNS disorders. With ongoing research on fucoidan, it is expected that a natural, highly effective, less toxic, and highly potent fucoidan-based drug or nutritional supplement targeting CNS diseases will be developed.

Crosstalk among mitophagy, pyroptosis, ferroptosis, and necroptosis in central nervous system injuries

Central nervous system injuries have a high rate of resulting in disability and mortality; however, at present, effective treatments are lacking. Programmed cell death, which is a genetically determined form of active and ordered cell death with many types, has recently attracted increasing attention due to its functions in determining the fate of cell survival. A growing number of studies have suggested that programmed cell death is involved in central nervous system injuries and plays an important role in the progression of brain damage. In this review, we provide an overview of the role of programmed cell death in central nervous system injuries, including the pathways involved in mitophagy, pyroptosis, ferroptosis, and necroptosis, and the underlying mechanisms by which mitophagy regulates pyroptosis, ferroptosis, and necroptosis. We also discuss the new direction of therapeutic strategies targeting mitophagy for the treatment of central nervous system injuries, with the aim to determine the connection between programmed cell death and central nervous system injuries and to identify new therapies to modulate programmed cell death following central nervous system injury. In conclusion, based on these properties and effects, interventions targeting programmed cell death could be developed as potential therapeutic agents for central nervous system injury patients.

Electroacupuncture Downregulating Neuronal Ferroptosis in MCAO/R Rats by Activating Nrf2/SLC7A11/GPX4 Axis

Ischemic stroke involves various pathological processes, among which ferroptosis is crucial. Previous studies by our group have indicated that electroacupuncture (EA) mitigates ferroptosis after ischemic stroke; however, the precise mechanism underlying this effect remains unclear. In the present study, we developed a rat model of middle cerebral artery occlusion/reperfusion. We chose the main acupoint of the treatment methods of the "Awakening and Opening of the Brain". Rats' neurological function and motor coordination were evaluated by neurological function score and the rotarod test, respectively, and the volume of cerebral infarction was analyzed by 2,3,5-triphenyltetrazolium chloride Staining. The cerebrovascular conditions were visualized by time-of-flight magentic resonance angiography. In addition, we detected changes in lipid peroxidation and endogenous antioxidant activity by measuring the malondialdehyde, glutathione, superoxide dismutase activities, glutathione/oxidized glutathione and reduced nicotinamide adenine dinucleotide phosphate/oxidized nicotinamide adenine dinucleotide phosphate ratios. Inductively coupled plasma-mass spectrometry, western blot, reverse transcription-polymerase chain reaction, fluoro-jade B staining, immunofluorescence analysis, and transmission electron microscopy were utilized to examine the influence of EA. The results indicate that EA treatment was effective in reversing neurological impairment, neuronal damage, and protecting mitochondrial morphology and decreasing the cerebral infarct volume in the middle cerebral artery occlusion/reperfusion rat model. EA reduced iron levels, inhibited lipid peroxidation, increased endogenous antioxidant activity, modulated the expression of several ferroptosis-related proteins, and promoted nuclear factor-E2-related factor 2 (Nrf2) nuclear translocation. However, the protective effect of EA was hindered by the Nrf2 inhibitor ML385. These findings suggest that EA can suppress ferroptosis and decrease damage caused by cerebral ischemia/reperfusion by activating Nrf2 and increasing the protein expression of solute carrier family 7 member 11 and glutathione peroxidase 4.

[Cell loss in retinal ischemia is associated with increased necroptosis]

BACKGROUND

Retinal ischemia plays a central pathophysiological role in numerous eye diseases, such as glaucoma. In addition to apoptosis, autophagy, necroptosis and ferroptosis are among the cell death mechanisms of ischemia; however, their role is not clearly understood and controversially discussed.

OBJECTIVE

The aim of this study is to gain an improved understanding of the role of alternative cell death mechanisms such as autophagy and necroptosis after retinal ischemia. Based on this, future autophagy-based or necroptosis-based therapeutic approaches could be developed.

MATERIAL AND METHODS

Retinal ischemia reperfusion was induced in one eye of 6 to 8‑week-old rats by temporarily increasing the intraocular pressure to 140 mm Hg (60 min), followed by reperfusion. The untreated contralateral eye served as a control. Retinas after ischemia and control retinas were examined 7 days after ischemia immunohistochemically with markers for retinal ganglion cells (RGC), astrocytes (GFAP) as well as an autophagy (LAMP1) and a necroptosis marker (RIPK3) (n = 6/group).

RESULTS

Ischemia reperfusion resulted in both significant RGC loss (p ≤ 0.001) and a significant increase of astrocyte area (p = 0.026) after 7 days. Interestingly, the number of autophagic LAMP1 positive cells was unchanged 7 days after ischemia (p = 0.272), whereas the number of necroptotic RIPK3 positive cells was significantly increased (p ≤ 0.001).

CONCLUSION

Necroptotic processes appear to be activated 7 days after ischemia reperfusion, contributing to retinal cell death and activation of astrocytes. Late autophagic processes are not activated 7 days after ischemia. Necroptosis-associated parameters could therefore be targeted as an early therapeutic approach after ischemia in the future.

The role of the AMPK/ERK1/2 signaling pathway in neuronal oxidative stress damage following cerebral ischemia-reperfusion

Cerebral ischemia-reperfusion injury involves a series of pathophysiological processes that occur when blood supply is restored after cerebral vascular obstruction, leading to neuronal damage. The AMPK/ERK1/2 signaling pathway has been identified as crucial in this process, although the exact mechanisms underlying the induction of ischemia-reperfusion injury remain unclear. In this study, we investigated the involvement of the AMPK/ERK1/2 signaling pathway in neuronal oxidative stress damage following cerebral ischemia-reperfusion by establishing animal and cell models. Our experimental results demonstrated that cerebral ischemia-reperfusion leads to oxidative stress damage, including cell apoptosis and mitochondrial dysfunction. Moreover, further experiments showed that inhibition of AMPK and ERK1/2 activity, using U0126 and Compound C respectively, could alleviate oxidative stress-induced cellular injury, improve mitochondrial morphology and function, reduce reactive oxygen species levels, increase superoxide dismutase levels, and suppress apoptosis. These findings clearly indicate the critical role of the AMPK/ERK1/2 signaling pathway in regulating oxidative stress damage and cerebral ischemia-reperfusion injury. The discoveries in this study provide a theoretical basis for further research and development of neuroprotective therapeutic strategies targeting the AMPK/ERK1/2 signaling pathway.

Electroacupuncture protects against cerebral ischemia-reperfusion injury through mitochondrial dynamics

Background

Electroacupuncture (EA) has been shown to promote functional recovery after cerebral ischemia-reperfusion (I/R) injury. However, the contribution of mitochondrial dynamics to recovery remains unclear. The aim of this study was to investigate whether mitochondrial dynamics are involved in the effects of EA on cerebral I/R injury.

Methods

The rats with cerebral I/R injury were established by the middle cerebral artery occlusion/reperfusion. Subsequently, EA was applied to Baihui (GV20) and Dazhui (GV14) acupoints, with 2 Hz/5 Hz in frequency, 1.0 mA in intensity, 20 min each time, once a day for seven consecutive days. The therapeutic outcomes were assessed by modified neurological severity score (mNSS), 2,3,5-Triphenyte-trazolium chloride (TTC) staining, and hematoxylin-eosin (HE) staining. Mitochondrial morphology was observed under transmission electron microscopy. Adenosine triphosphate (ATP) content and ATP synthases (ATPases) activity were evaluated to measure mitochondrial function using ELISA. Finally, mitochondrial dynamics-related molecules, including dynamin-related protein 1 (Drp1), fission 1 (Fis1), mitofusin 1 (Mfn1), mitofusin 2 (Mfn2), and optic atrophy 1 (OPA1), were detected by Western blot and immunofluorescence staining.

Results

Cerebral I/R injury induced neurological dysfunction, cerebral infarction and neuronal injury, all of which were ameliorated by EA. And EA improved mitochondrial morphology and function. Moreover, EA altered the balance of mitochondrial dynamics. Specifically, the data showed a significant decrease in the expression of Drp1 and Fis1, leading to the inhibition of mitochondrial fission. Additionally, Mfn1, Mfn2 and Opa1, which are related to mitochondrial fusion, were effectively promoted after EA treatment. However, sham EA did not show any neuroprotective effects in rats with cerebral I/R injury.

Conclusions

In summary, our study indicates that the balance of mitochondrial dynamics is crucial for EA therapy to treat cerebral I/R injury.

TUG1 exacerbates cerebral ischemia-reperfusion injury through miR-340-5p-mediated PTEN

Long non-coding RNAs (LncRNAs) play a substantial role in the process of cerebral ischemia-reperfusion injury (CIRI). The present work aimed to determine the probable mechanism by which LncRNA TUG1 exacerbates CIRI via the miR-340-5p/phosphatase and tensin homolog (PTEN) pathway. After developing a middle cerebral artery occlusion/reperfusion (MCAO/R) model, pcDNA-TUG1 together with miR-340-5p agomir were administrated in vivo. Furthermore, the neurologic defects in rats were assessed by a modified neurological severity score. Moreover, 2,3,5-Triphenyl-2 H-tetrazolium chloride stain-step was performed to determine the brain's infarct size. In addition, western blotting, immunohistochemistry, and qRT-PCR experiments were utilized for gauging the proteomic/genomic expression-profiles. Luciferase reporter assay validated correlations across TUG1, miR-340-5p, together with PTEN. The results indicated relatively reduced miR-340-5p levels in MCAO/R models, while upregulated TUG1 levels. The pcDNA-TUG1-treated rats indicated increasing neurological dysfunction, whereas the miR-340-5p agomir-treated rats showed improvement. Furthermore, miR-340-5p was determined to be the expected and confirmed TUG1 target. All things considered, the findings suggested that PTEN can serve as the target of miR-340-5p. In addition, TUG1 served as a miR-340-5p ceRNA, which promotes PTEN modulation. Furthermore, TUG1 overexpression decreased miR-340-5p's capacity to fend against CIRI. Conclusively, this work proved that in CIRI, targeting the TUG1/miR-340-5p/PTEN regulatory axis is a viable approach for the treatment of ischemic stroke.

Ginsenoside Rg1 mitigates cerebral ischaemia/reperfusion injury in mice by inhibiting autophagy through activation of mTOR signalling

Reperfusion injury, which is distinct from ischaemic injury, occurs when blood flow is restored in previously ischaemic brain tissue, further compromising neurons and other cells and worsening the injury. There is currently a lack of pharmaceutical agents and therapeutic interventions that specifically mitigate cerebral ischaemia/reperfusion (I/R) injury. Ginsenoside Rg1 (Rg1), a protopanaxatriol-type saponin isolated from Panax ginseng C. A. Meyer, has been found to protect against cerebral I/R injury, but its intricate protective mechanisms remain to be elucidated. Numerous studies have shown that autophagy plays a crucial role in protecting brain tissue during the I/R process and is emerging as a promising therapeutic strategy for effective treatment. In this study, we investigated whether Rg1 protected against I/R damage in vitro and in vivo by regulating autophagy. Both MCAO and OGD/R models were established. SK-N-AS and SH-SY5Y cells were subjected to OGD followed by reperfusion with Rg1 (4-32 μM). MCAO mice were injected with Rg1 (30 mg·kg-1·d-1. i.p.) for 3 days before and on the day of surgery. Rg1 treatment significantly mitigated ischaemia/reperfusion injury both in vitro and in vivo. Furthermore, we demonstrated that the induction of autophagy contributed to I/R injury, which was effectively inhibited by Rg1 in both in vitro and in vivo models of cerebral I/R injury. Rg1 inhibited autophagy through multiple steps, including impeding autophagy initiation, inducing lysosomal dysfunction and inhibiting cathepsin enzyme activities. We revealed that mTOR activation was pivotal in mediating the inhibitory effect of Rg1 on autophagy. Treatment with Torin-1, an autophagy inducer and mTOR-specific inhibitor, significantly reversed the impact of Rg1 on autophagy, decreasing its protective efficacy against I/R injury both in vitro and in vivo. In conclusion, our results suggest that Rg1 may serve as a promising drug candidate against cerebral I/R injury by inhibiting autophagy through activation of mTOR signalling.

Tapping into Nature's Arsenal: Harnessing the Potential of Natural Antioxidants for Human Health and Disease Prevention

Numerous natural antioxidants commonly found in our daily diet have demonstrated significant benefits for human health and various diseases by counteracting the impact of reactive oxygen and nitrogen species. Their chemical properties enable a range of biological actions, including antihypertensive, antimicrobial, anti-inflammatory, anti-fibrotic, and anticancer effects. Despite promising outcomes from preclinical studies, ongoing debate persists regarding their reproducibility in human clinical models. This controversy largely stems from a lack of understanding of the pharmacokinetic properties of these compounds, coupled with the predominant focus on monotherapies in research, neglecting potential synergistic effects arising from combining different antioxidants. This study aims to provide an updated overview of natural antioxidants, operating under the hypothesis that a multitherapeutic approach surpasses monotherapy in efficacy. Additionally, this study underscores the importance of integrating these antioxidants into the daily diet, as they have the potential to prevent the onset and progression of various diseases. To reinforce this perspective, clinical findings pertaining to the treatment and prevention of non-alcoholic fatty liver disease and conditions associated with ischemia and reperfusion phenomena, including myocardial infarction, postoperative atrial fibrillation, and stroke, are presented as key references.

Neuregulin-1, a member of the epidermal growth factor family, mitigates STING-mediated pyroptosis and necroptosis in ischaemic flaps

Background

Ensuring the survival of the distal end of a random flap during hypoperfusion (ischaemia) is difficult in clinical practice. Effective prevention of programmed cell death is a potential strategy for inhibiting ischaemic flap necrosis. The activation of stimulator of interferon genes (STING) pathway promotes inflammation and leads to cell death. The epidermal growth factor family member neuregulin-1 (NRG1) reduces cell death by activating the protein kinase B (AKT) signalling pathway. Moreover, AKT signalling negatively regulates STING activity. We aimed to verify the efficacy of NRG1 injection in protecting against flap necrosis. Additionally, we investigated whether NRG1 effectively enhances ischemic flap survival by inhibiting pyroptosis and necroptosis through STING suppression.

Methods

A random-pattern skin flap model was generated on the backs of C57BL/6 mice. The skin flap survival area was determined. The blood supply and vascular network of the flap was assessed by laser Doppler blood flow analysis. Cluster of differentiation 34 immunohistochemistry (IHC) and haematoxylin and eosin (H&E) staining of the flap sections revealed microvessels. Transcriptome sequencing analysis revealed the mechanism by which NRG1 promotes the survival of ischaemic flaps. The levels of angiogenesis, oxidative stress, necroptosis, pyroptosis and indicators associated with signalling pathways in flaps were examined by IHC, immunofluorescence and Western blotting. Packaging adeno-associated virus (AAV) was used to activate STING in flaps.

Results

NRG1 promoted the survival of ischaemic flaps. An increased subcutaneous vascular network and neovascularization were found in ischaemic flaps after the application of NRG1. Transcriptomic gene ontology enrichment analysis and protein level detection indicated that necroptosis, pyroptosis and STING activity were reduced in the NRG1 group. The phosphorylation of AKT and forkhead box O3a (FOXO3a) were increased after NRG1 treatment. The increased expression of STING in flaps induced by AAV reversed the therapeutic effect of NRG1. The ability of NRG1 to phosphorylate AKT-FOXO3a, inhibit STING and promote flap survival was abolished after the application of the AKT inhibitor MK2206.

Conclusions

NRG1 inhibits pyroptosis and necroptosis by activating the AKT-FOXO3a signalling pathway to suppress STING activation and promote ischaemic flap survival.

Caspase-1 deletion reveals pyroptosis participates in neural damage induced by cerebral ischemia/reperfusion in tMCAO model mice

Pyroptosis, a form of programmed cell death, drives inflammation in the context of cerebral ischemia/reperfusion. The molecular mechanism of pyroptosis underlying ischemia/reperfusion, however, is not fully understood. The transient middle cerebral artery occlusion was applied to wild-type and caspase-1 knockout mice. 2,3,5-Triphenyltetrazolium chloride-staining and immunohistochemistry were used to identify the ischemic region, and western blot and immunofluorescence for the examination of neuronal pyroptosis. The expression of inflammatory factors and the behavioral function assessments were further conducted to examine the effects of caspase-1 knockout on protection against ischemia/reperfusion injury. Ischemia/reperfusion injury increased pyroptosis-related signals represented by the overexpression of pyroptosis-related proteins including caspase-1 and gasdermin D (GSDMD). Meanwhile, the number of GSDMD positive neurons increased in penumbra by immunofluorescence staining. Compared with wild-type mice, those with caspase-1 knockout exhibited decreased levels of pyroptosis-related proteins following ischemia/reperfusion. Furthermore, ischemia/reperfusion attack-induced brain infarction, cerebral edema, inflammatory factors, and neurological outcomes were partially improved in caspase-1 knockout mice. The data indicate that pyroptosis participates in ischemia/reperfusion induced-damage, and the caspase-1 might be involved, it provides some new insights into the molecular mechanism of ischemia.

Research progress of prodrugs for the treatment of cerebral ischemia

It is well-known that pharmacotherapy plays a pivotal role in the treatment and prevention of cerebral ischemia. Nevertheless, existing drugs, including numerous natural products, encounter various challenges when applied in cerebral ischemia treatment. These challenges comprise poor brain absorption due to low blood-brain barrier (BBB) permeability, limited water solubility, inadequate bioavailability, poor stability, and rapid metabolism. To address these issues, researchers have turned to prodrug strategies, aiming to mitigate or eliminate the adverse properties of parent drug molecules. In vivo metabolism or enzymatic reactions convert prodrugs into active parent drugs, thereby augmenting BBB permeability, improving bioavailability and stability, and reducing toxicity to normal tissues, ultimately aiming to enhance treatment efficacy and safety. This comprehensive review delves into multiple effective prodrug strategies, providing a detailed description of representative prodrugs developed over the past two decades. It underscores the potential of prodrug approaches to improve the therapeutic outcomes of currently available drugs for cerebral ischemia. The publication of this review serves to enrich current research progress on prodrug strategies for the treatment and prevention of cerebral ischemia. Furthermore, it seeks to offer valuable insights for pharmaceutical chemists in this field, offer guidance for the development of drugs for cerebral ischemia, and provide patients with safer and more effective drug treatment options.

Overexpression of olfactory receptor 78 ameliorates brain injury in cerebral ischaemia-reperfusion rats by activating Prkaca-mediated cAMP/PKA-MAPK pathway

Ischemic stroke is one of the main causes of disability and death. However, recanalization of occluded cerebral arteries is effective only within a very narrow time window. Therefore, it is particularly important to find neuroprotective biological targets for cerebral artery recanalization. Here, gene expression profiles of datasets GSE160500 and GSE97537 were downloaded from the GEO database, which were related to ischemic stroke in rats. Olfactory receptor 78 (Olfr78) was screened, and which highly associated with Calcium signalling pathway and MAPK pathway. Interacting protein of Olfr78, Prkaca, was predicted by STRING, and their interaction was validated by Co-IP analysis. Then, a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) and a neuronal cell model stimulated by oxygen-glucose deprivation/reoxygenation (OGD/R) were constructed, and the results showed that expression of Olfr78 and Prkaca was downregulated in MCAO rats and OGD/R-stimulated neurons. Overexpression of Olfr78 or Prkaca inhibited the secretion of inflammatory factors, Ca2+ overload, and OGD/R-induced neuronal apoptosis. Moreover, Overexpression of Prkaca increased protein levels of cAMP, PKA and phosphorylated p38 in OGD/R-stimulated neurons, while SB203580, a p38 inhibitor, treatment inhibited activation of the cAMP/PKA-MAPK pathway and counteracted the effect of Olfr78 overexpression on improvement of neuronal functions. Meanwhile, overexpression of Olfr78 or Prkaca markedly inhibited neuronal apoptosis and improved brain injury in MCAO/R rats. In conclusion, overexpression of Olfr78 inhibited Ca2+ overload and reduced neuronal apoptosis in MCAO/R rats by promoting Prkaca-mediated activation of the cAMP/PKA-MAPK pathway, thereby improving brain injury in cerebral ischaemia-reperfusion.

Aquaporins alteration revealed kidney damages in cerebral ischemia/reperfusion rats

Background

Restoration of blood supply is a desired goal for the treatment of acute ischemic stroke. However, the restoration often leads to cerebral ischemia-reperfusion injury (CIR/I), which greatly increases the risk of non-neural organ damage. In particular, the acute kidney injury might be one of the most common complications.

Aims

The study aimed to understand the damage occurred and the potential molecular mechanisms.

Methods

The study was explored on the CIR/I rats generated by performing middle cerebral artery occlusion/reperfusion (MCAO/Reperfusion). The rats were evaluated with injury on the brains, followed by the non-neural organs including kidneys, livers, colons and stomachs. They were examined further with histopathological changes, and gene expression alterations by using RT-qPCR of ten aquaporins (Aqps) subtypes including Aqp1～Aqp9 and Aqp11. Furthermore, the Aqps expression profiles were constructed for each organ and analyzed by performing Principle Component Analysis. In addition, immunohistochemistry was explored to look at the protein expression of Aqp1, Aqp2, Aqp3 and Aqp4 in the rat kidneys.

Results

There was a prominent down-regulation profile in the MCAO/Reperfusion rat kidneys. The protein expression of Aqp1, Aqp2, Aqp3 and Aqp4 was decreased in the kidneys of the MCAO/Reperfusion rats. We suggested that the kidney was in the highest risk to be damaged following the CIR/I. Down-regulation of Aqp2, Aqp3 and Aqp4 was involved in the acute kidney injury induced by the CIR/I.

Sophoricoside ameliorates cerebral ischemia-reperfusion injury dependent on activating AMPK

AIMS

Ischemic stroke accounts for 87% of all strokes, and its death and disability bring a huge burden to society. Brain injury caused by ischemia-reperfusion (I/R) is also a major difficulty in clinical treatment and prognosis. Sophoricoside (SOP) is an isoflavone glycoside isolated from the seed of medical herb Sophora japonica L. Previously, SOP was found to be effective in anti-inflammation and glucose-lipid metabolism-related diseases. In order to investigate whether SOP has a regulatory effect on cerebral I/R injury, we conducted this study.

METHODS

Here, by application of SOP into MCAO (transient middle cerebral artery occlusion)-induced mice and OGD/R (oxygen glucose deprivation/reperfusion)-induced primary neurons, the regulation effects of SOP was analyzed by detecting neurological score of post-stroke mice, phenotypes of brains and brain sections, cell viabilities, and apoptosis- and inflammation-regulation. RNA sequencing and molecular biology experiments were performed to explore the mechanism of SOP regulating cerebral I/R injury.

RESULTS

SOP administration decreased the infarct size, neurological deficit score, neuronal cell injury, inflammation and apoptosis. Mechanistically, SOP exerted its protective effect by activating the AMP-activated protein kinase (AMPK) signaling pathway.

CONCLUSION

SOP inhibits cerebral I/R injury by promoting the phosphorylation of AMPK.

Experımental Study: The Effect Of 20% Intralıpıd Emulsıon Therapy In Cerebral Ischemıc Reperfusıon

BACKGROUND

This experimental study was conducted to investigate the effect of 20% Intralipid Emulsion (ILE) treatment on Cerebral Ischemia Reperfusion Injury (CIRI) after reperfusion in acute ischemic stroke.

METHODS

In this experimental study, seven rats without any intervention (control group), seven rats (sham group) for which CIRI was created after the common carotid artery was ligated for 2 hours, and seven rats who were treated with 20% ILE after CIRI (CIRI + ILE group) were sacrificed after 24 hours, and histopathological findings were investigated.

RESULTS

In rats that were not treated after CIRI, 52.7% had level-1, 32.7% had level-2. and 14.5% had level-3. histopathological findings. While 72.2% of the rats treated with ILE had level-1 and 27.8% had level-2 findings, no level-3 histopathological findings were detected in any of the rats. While no signs of coagulative necrosis, spongiosis of surrounding tissue and polymorphonuclear leukocytes were observed histopathological in any of the rats given ILE, there was no macrophages finding in 85.6% of the rats. ILE treatment also reduced the histopathological findings of eosinophilic neurons, astrogliosis, neovascularization, vascular thrombosis and mononuclear inflammatory cells.

CONCLUSION

This study showed that 20% ILE treatment reduces the histopathological damage seen in cerebral ischemia and CIRI.

Insight into the pathophysiological advances and molecular mechanisms underlying cerebral stroke: current status

Molecular pathways involved in cerebral stroke are diverse. The major pathophysiological events that are observed in stroke comprises of excitotoxicity, oxidative stress, mitochondrial damage, endoplasmic reticulum stress, cellular acidosis, blood-brain barrier disruption, neuronal swelling and neuronal network mutilation. Various biomolecules are involved in these pathways and several major proteins are upregulated and/or suppressed following stroke. Different types of receptors, ion channels and transporters are activated. Fluctuations in levels of various ions and neurotransmitters have been observed. Cells involved in immune responses and various mediators involved in neuro-inflammation get upregulated progressing the pathogenesis of the disease. Despite of enormity of the problem, there is not a single therapy that can limit infarction and neurological disability due to stroke. This is because of poor understanding of the complex interplay between these pathophysiological processes. This review focuses upon the past to present research on pathophysiological events that are involved in stroke and various factors that are leading to neuronal death following cerebral stroke. This will pave a way to researchers for developing new potent therapeutics that can aid in the treatment of cerebral stroke.

REMIMAZOLAM IMPROVES THE MARKERS OF POSTRESUSCITATION CEREBRAL INJURY IN A SWINE MODEL OF CARDIAC ARREST

ABSTRACT

Introduction: Previous studies have manifested that those sedatives acting on γ-aminobutyric acid A (GABAa) receptor could produce effective brain protection against regional and global ischemic stimulation. The present study was designed to investigate the effect of a novel GABAa receptor agonist, remimazolam postconditioning (RP) on cerebral outcome after global ischemic stimulation induced by cardiac arrest and resuscitation in swine. Methods: A total of 24 swine were used in this study, in which the animals were randomly divided into the following three groups: sham group (n = 6), cardiopulmonary resuscitation (CPR) group (n = 9), and CPR + RP group (n = 9). The experimental model was established by the procedure of 10 min of cardiac arrest and 5 min of CPR. Those resuscitated swine in the CPR + RP group received an intravenous infusion of 2.5 mg/kg of remimazolam within 60 min. Postresuscitation cerebral injury biomarkers and neurological function were evaluated for a total of 24 h. At 24 h after resuscitation, brain cortex was harvested to evaluate the severity of pathologic damage, including tissue inflammation, oxidative stress, apoptosis, and necroptosis. Results: Baseline characteristics and CPR outcomes were not significantly different between the CPR and CPR + RP groups. After resuscitation, significantly greater cerebral injury and neurological dysfunction were observed in the CPR and CPR + RP groups than in the sham group. However, remimazolam postconditioning significantly alleviated cerebral injury and improved neurological dysfunction after resuscitation when compared with the CPR group. At 24 h after resuscitation, tissue inflammation, oxidative stress, and cell apoptosis and necroptosis were significantly increased in the CPR and CPR + RP groups when compared with the sham group. Nevertheless, the severity of pathologic damage mentioned previously were significantly milder in those swine treated with the remimazolam when compared with the CPR group. Conclusions: In a swine model of cardiac arrest and resuscitation, the remimazolam administered after resuscitation significantly improved the markers of postresuscitation cerebral injury and therefore protected the brain against global ischemic stimulation.

Increasing expression of dual-specificity phosphatase 12 mitigates oxygen-glucose deprivation/reoxygenation-induced neuronal apoptosis and inflammation through inactivation of the ASK1-JNK/p38 MAPK pathway

Dual-specificity phosphatase 12 (DUSP12) is abnormally expressed under various pathological conditions and plays a crucial role in the pathological progression of disorders. However, the role of DUSP12 in cerebral ischaemia/reperfusion injury has not yet been investigated. This study explored the possible link between DUSP12 and cerebral ischaemia/reperfusion injury using an oxygen-glucose deprivation/reoxygenation (OGD/R) model. Marked decreases in DUSP12 levels have been observed in cultured neurons exposed to OGD/R. DUSP12-overexpressed neurons were resistant to OGD/R-induced apoptosis and inflammation, whereas DUSP12-deficient neurons were vulnerable to OGD/R-evoked injuries. Further investigation revealed that DUSP12 overexpression or deficiency affects the phosphorylation of apoptosis signal-regulating kinase 1 (ASK1), c-Jun NH2-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) in neurons under OGD/R conditions. Moreover, blockade of ASK1 diminished the regulatory effect of DUSP12 deficiency on JNK and p38 MAPK activation. In addition, DUSP12-deficiency-elicited effects exacerbating neuronal OGD/R injury were reversed by ASK1 blockade. In summary, DUSP12 protects against neuronal OGD/R injury by reducing apoptosis and inflammation through inactivation of the ASK1-JNK/p38 MAPK pathway. These findings imply a neuroprotective function for DUSP12 in cerebral ischaemia/reperfusion injury.

1-Phosphate receptor agonists: A promising therapeutic avenue for ischemia-reperfusion injury management

Ischemia-reperfusion injury (IRI) - a complex pathological condition occurring when blood supply is abruptly restored to ischemic tissues, leading to further tissue damage - poses a significant clinical challenge. Sphingosine-1-phosphate receptors (S1PRs), a specialized set of G-protein-coupled receptors comprising five subtypes (S1PR1 to S1PR5), are prominently present in various cell membranes, including those of lymphocytes, cardiac myocytes, and endothelial cells. Increasing evidence highlights the potential of targeting S1PRs for IRI therapeutic intervention. Notably, preconditioning and postconditioning strategies involving S1PR agonists like FTY720 have demonstrated efficacy in mitigating IRI. As the synthesis of a diverse array of S1PR agonists continues, with FTY720 being a prime example, the body of experimental evidence advocating for their role in IRI treatment is expanding. Despite this progress, comprehensive reviews delineating the therapeutic landscape of S1PR agonists in IRI remain limited. This review aspires to meticulously elucidate the protective roles and mechanisms of S1PR agonists in preventing and managing IRI affecting various organs, including the heart, kidney, liver, lungs, intestines, and brain, to foster novel pharmacological approaches in clinical settings.

Acupuncture Extended the Thrombolysis Window by Suppressing Blood-Brain Barrier Disruption and Regulating Autophagy-Apoptosis Balance after Ischemic Stroke

BACKGROUND

Ischemic stroke (IS) is one of the leading causes of death and disability worldwide. The narrow therapeutic window (within 4.5 h) and severe hemorrhagic potential limits therapeutic efficacy of recombinant tissue type plasminogen activator (rt-PA) intravenous thrombolysis for patients. Xingnao Kaiqiao (XNKQ) acupuncture is an integral part of traditional Chinese medicine, specifically designed to address acute ischemic stroke by targeting key acupoints such as Shuigou (GV26) and Neiguan (PC6). In this study, we explored the therapeutic potential of XNKQ acupuncture in extending the time window for thrombolysis and interrogated the molecular mechanisms responsible for this effect.

METHODS

The effect of extending the thrombolysis window by acupuncture was evaluated via TTC staining, neuronal score evaluation, hemorrhagic transformation assay, and H&E staining. RNA sequencing (RNA-seq) technology was performed to identify the therapeutic targets and intervention mechanisms of acupuncture. Evans blue staining and transmission electron microscopy were used to assess blood-brain barrier (BBB) integrity. Immunofluorescence staining and co-immunoprecipitation were performed to evaluate the level of autophagy and apoptosis and validate their interactions with BBB endothelial cells.

RESULTS

Acupuncture alleviated infarction and neurological deficits and extended the thrombolysis window to 6 h. The RNA-seq revealed 16 potential therapeutic predictors for acupuncture intervention, which related to suppressing inflammation and restoring the function of BBB and blood vessels. Furthermore, acupuncture suppressed BBB leakage and preserved tight junction protein expression. The protective effect was associated with regulation of the autophagy-apoptosis balance in BBB endothelial cells. Acupuncture intervention dissociated the Beclin1/Bcl-2 complex, thereby promoting autophagy and reducing apoptosis.

CONCLUSION

XNKQ acupuncture could serve as an adjunctive therapy for rt-PA thrombolysis, aiming to extend the therapeutic time window and mitigate ischemia-reperfusion injury. Acupuncture suppressed BBB disruption by regulating the autophagy-apoptosis balance, which in turn extended the therapeutic window of rt-PA in IS. These findings provide a rationale for further exploration of acupuncture as a complementary candidate co-administered with rt-PA.

Necroptosis contributes to non-alcoholic fatty liver disease pathoetiology with promising diagnostic and therapeutic functions

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent type of chronic liver disease. However, the disease is underappreciated as a remarkable chronic disorder as there are rare managing strategies. Several studies have focused on determining NAFLD-caused hepatocyte death to elucidate the disease pathoetiology and suggest functional therapeutic and diagnostic options. Pyroptosis, ferroptosis, and necroptosis are the main subtypes of non-apoptotic regulated cell deaths (RCDs), each of which represents particular characteristics. Considering the complexity of the findings, the present study aimed to review these types of RCDs and their contribution to NAFLD progression, and subsequently discuss in detail the role of necroptosis in the pathoetiology, diagnosis, and treatment of the disease. The study revealed that necroptosis is involved in the occurrence of NAFLD and its progression towards steatohepatitis and cancer, hence it has potential in diagnostic and therapeutic approaches. Nevertheless, further studies are necessary.

Progress of medicinal plants and their active metabolites in ischemia-reperfusion injury of stroke: a novel therapeutic strategy based on regulation of crosstalk between mitophagy and ferroptosis

The death of cells can occur through various pathways, including apoptosis, necroptosis, mitophagy, pyroptosis, endoplasmic reticulum stress, oxidative stress, ferroptosis, cuproptosis, and disulfide-driven necrosis. Increasing evidence suggests that mitophagy and ferroptosis play crucial regulatory roles in the development of stroke. In recent years, the incidence of stroke has been gradually increasing, posing a significant threat to human health. Hemorrhagic stroke accounts for only 15% of all strokes, while ischemic stroke is the predominant type, representing 85% of all stroke cases. Ischemic stroke refers to a clinical syndrome characterized by local ischemic-hypoxic necrosis of brain tissue due to various cerebrovascular disorders, leading to rapid onset of corresponding neurological deficits. Currently, specific therapeutic approaches targeting the pathophysiological mechanisms of ischemic brain tissue injury mainly include intravenous thrombolysis and endovascular intervention. Despite some clinical efficacy, these approaches inevitably lead to ischemia-reperfusion injury. Therefore, exploration of treatment options for ischemic stroke remains a challenging task. In light of this background, advancements in targeted therapy for cerebrovascular diseases through mitophagy and ferroptosis offer a new direction for the treatment of such diseases. In this review, we summarize the progress of mitophagy and ferroptosis in regulating ischemia-reperfusion injury in stroke and emphasize their potential molecular mechanisms in the pathogenesis. Importantly, we systematically elucidate the role of medicinal plants and their active metabolites in targeting mitophagy and ferroptosis in ischemia-reperfusion injury in stroke, providing new insights and perspectives for the clinical development of therapeutic drugs for these diseases.

Luteolin-7-O-β-d-glucuronide Ameliorates Cerebral Ischemic Injury: Involvement of RIP3/MLKL Signaling Pathway

Luteolin-7-O-β-d-glucuronide (LGU) is a major active flavonoid glycoside compound that is extracted from Ixeris sonchifolia (Bge.) Hance, and it is a Chinese medicinal herb mainly used for the treatment of coronary heart disease, angina pectoris, cerebral infarction, etc. In the present study, the neuroprotective effect of LGU was investigated in an oxygen glucose deprivation (OGD) model and a middle cerebral artery occlusion (MCAO) rat model. In vitro, LGU was found to effectively improve the OGD-induced decrease in neuronal viability and increase in neuronal death by a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and a lactate dehydrogenase (LDH) leakage rate assay, respectively. LGU was also found to inhibit OGD-induced intracellular Ca2+ overload, adenosine triphosphate (ATP) depletion, and mitochondrial membrane potential (MMP) decrease. By Western blotting analysis, LGU significantly inhibited the OGD-induced increase in expressions of receptor-interacting serine/threonine-protein kinase 3 (RIP3) and mixed lineage kinase domain-like protein (MLKL). Moreover, molecular docking analysis showed that LGU might bind to RIP3 more stably and firmly than the RIP3 inhibitor GSK872. Immunofluorescence combined with confocal laser analyses disclosed that LGU inhibited the aggregation of MLKL to the nucleus. Our results suggest that LGU ameliorates OGD-induced rat primary cortical neuronal injury via the regulation of the RIP3/MLKL signaling pathway in vitro. In vivo, LGU was proven, for the first time, to protect the cerebral ischemia in a rat middle cerebral artery occlusion (MCAO) model, as shown by improved neurological deficit scores, infarction volume rate, and brain water content rate. The present study provides new insights into the therapeutic potential of LGU in cerebral ischemia.

What can the common fruit fly teach us about stroke?: lessons learned from the hypoxic tolerant Drosophila melanogaster

Stroke, resulting in hypoxia and glucose deprivation, is a leading cause of death and disability worldwide. Presently, there are no treatments that reduce neuronal damage and preserve function aside from tissue plasminogen activator administration and rehabilitation therapy. Interestingly, Drosophila melanogaster, the common fruit fly, demonstrates robust hypoxic tolerance, characterized by minimal effects on survival and motor function following systemic hypoxia. Due to its organized brain, conserved neurotransmitter systems, and genetic similarity to humans and other mammals, uncovering the mechanisms of Drosophila's tolerance could be a promising approach for the development of new therapeutics. Interestingly, a key facet of hypoxic tolerance in Drosophila is organism-wide metabolic suppression, a response involving multiple genes and pathways. Specifically, studies have demonstrated that pathways associated with oxidative stress, insulin, hypoxia-inducible factors, NFκB, Wnt, Hippo, and Notch, all potentially contribute to Drosophila hypoxic tolerance. While manipulating the oxidative stress response and insulin signaling pathway has similar outcomes in Drosophila hypoxia and the mammalian middle cerebral artery occlusion (MCAO) model of ischemia, effects of Notch pathway manipulation differ between Drosophila and mammals. Additional research is warranted to further explore how other pathways implicated in hypoxic tolerance in Drosophila, such as NFκB, and Hippo, may be utilized to benefit mammalian response to ischemia. Together, these studies demonstrate that exploration of the hypoxic response in Drosophila may lead to new avenues of research for stroke treatment in humans.

Effect of the Novel Free Radical Scavenger 4'-Hydroxyl-2-Substituted Phenylnitronyl Nitroxide on Oxidative Stress, Mitochondrial Dysfunction and Apoptosis Induced by Cerebral Ischemia-Reperfusion in Rats

Mitochondrial dysfunction, which results in the overproduction of oxygen free radicals, is a crucial mechanism underlying cerebral ischemia-reperfusion injury. 4'-Hydroxyl-2-substituted phenylnitronyl nitroxide (HPN), which is an antioxidant and free radical scavenger, can effectively scavenge oxygen free radicals, suggesting its potential as a protective agent against cerebral ischemia-reperfusion injury. In this study, we investigated the effects of HPN on mitochondrial function and apoptosis following cerebral ischemia/reperfusion injury in rats. Healthy adult SD rats were chosen as the experimental subjects, and the rat ischemia/reperfusion injury model was generated using the modified Zea Longa method. The administration of HPN significantly enhanced the activity of endogenous antioxidant enzymes, such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT). Additionally, HPN effectively preserved the morphology and function of mitochondria, reduced the protein and gene expression of Caspase-3 and Bax, increased the protein and gene expression of Bcl-2, mitigated neuronal apoptosis, improved neurological deficits, and decreased the volume of cerebral infarction. Of interest, the protective effect on brain tissue was more evident with increasing doses of HPN. These findings indicate that HPN can serve as an effective protective agent against cerebral ischemia-reperfusion injury.

High-frequency repetitive transcranial magnetic stimulation promotes ipsilesional functional hyperemia and motor recovery in mice with ischemic stroke

Neurovascular decoupling plays a significant role in dysfunction following an ischemic stroke. This study aimed to explore the effect of low- and high-frequency repetitive transcranial magnetic stimulation on neurovascular remodeling after ischemic stroke. To achieve this goal, we compared functional hyperemia, cerebral blood flow regulatory factors, and neurochemical transmitters in the peri-infract cortex 21 days after a photothrombotic stroke. Our findings revealed that low- and high-frequency repetitive transcranial magnetic stimulation increased the real-time cerebral blood flow in healthy mice and improved neurobehavioral outcomes after stroke. Furthermore, high-frequency (5-Hz) repetitive transcranial magnetic stimulation revealed stronger functional hyperemia recovery and increased the levels of post-synaptic density 95, neuronal nitric oxide synthase, phosphorylated-endothelial nitric oxide synthase, and vascular endothelial growth factor in the peri-infract cortex compared with low-frequency (1-Hz) repetitive transcranial magnetic stimulation. The magnetic resonance spectroscopy data showed that low- and high-frequency repetitive transcranial magnetic stimulation reduced neuronal injury and maintained excitation/inhibition balance. However, 5-Hz repetitive transcranial magnetic stimulation showed more significant regulation of excitatory and inhibitory neurotransmitters after stroke than 1-Hz repetitive transcranial magnetic stimulation. These results indicated that high-frequency repetitive transcranial magnetic stimulation could more effectively promote neurovascular remodeling after stroke, and specific repetitive transcranial magnetic stimulation frequencies might be used to selectively regulate the neurovascular unit.

Nuciferine reduces inflammation induced by cerebral ischemia-reperfusion injury through the PI3K/Akt/NF-κB pathway

BACKGROUND

Cerebral ischemia has the characteristics of high incidence, mortality, and disability, which seriously damages people's health. Cerebral ischemia-reperfusion injury is the key pathological injury of this disease. However, there is a lack of drugs that can reduce cerebral ischemia-reperfusion injury in clinical practice. At present, a few studies have provided some evidence that nuciferine can reduce cerebral ischemia-reperfusion injury, but its specific mechanism of action is still unclear, and further research is still needed.

OBJECTIVE

In this study, PC12 cells and SD rats were used to construct OGD/R and MCAO/R models, respectively. Combined with bioinformatics methods and experimental verification methods, the purpose of this study was to conduct a systematic and comprehensive study on the effect and mechanism of nuciferine on reducing inflammation induced by cerebral ischemia-reperfusion injury.

RESULTS

Nuciferine can improve the cell viability of PC12 cells induced by OGD/R, reduce apoptosis, and reduce the expression of inflammation-related proteins; it can also improve the cognitive and motor dysfunction of MCAO/R-induced rats by behavioral tests, reduce the area of cerebral infarction, reduce the release of inflammatory factors TNF-α and IL-6 in serum and the expression of inflammation-related proteins in brain tissue.

CONCLUSION

Nuciferine can reduce the inflammatory level of cerebral ischemia-reperfusion injury in vivo and in vitro models by acting on the PI3K/Akt/NF-κB signaling pathway, and has the potential to be developed as a drug for the treatment of cerebral ischemia-reperfusion injury.

IL-17A deficiency alleviates cerebral ischemia-reperfusion injury via activating ERK/MAPK pathway in hippocampal CA1 region

Cognitive impairment is a major complication of cerebral ischemia-reperfusion (CIR) injury and has an important impact on the quality of life of patients. However, the precise mechanisms underlying cognitive impairment after CIR injury remain elusive. In the current study, we investigated the role of interleukin 17 A (IL-17A) on CIR injury-induced cognitive impairment in wild-type and IL-17A knockout mice using RNA sequencing analysis, neurological assessments, Golgi-Cox staining, dendritic spine analysis, immunofluorescence assay, and western blot analysis. RNA sequencing identified 195 CIR-induced differentially expressed genes (83 upregulated and 112 downregulated), highlighting several enriched biological processes (negative regulation of phosphorylation, transcription regulator complex, and receptor ligand activity) and signaling pathways (mitogen-activated protein kinase [MAPK], tumor necrosis factor, and IL-17 signaling pathways). We also injected adeno-associated virus into the bilateral hippocampal CA1 regions of CIR mice to upregulate or downregulate cyclic AMP response element-binding protein. IL-17A knockout activated the extracellular signal-regulated kinase (ERK)/MAPK signaling pathway and further improved synaptic plasticity, structure, and function in CIR mice. Together, our findings suggest that IL-17A deficiency alleviates CIR injury by activating the ERK/MAPK signaling pathway and enhancing hippocampal synaptic plasticity.

Wogonin alleviates NLRP3 inflammasome activation after cerebral ischemia-reperfusion injury by regulating AMPK/SIRT1

Cerebral ischemia-reperfusion (IR) is the main pathophysiological process after stroke and can seriously impair neurological function. Wogonin, a natural flavonoid extracted from the roots of Scutellaria baicalensis, has potent anti-inflammatory properties. In this study, we investigated the protective mechanism of wogonin against middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation/reoxygenation (OGD/R) model-induced cerebral IR injury through adenosine 5'-monophosphate-activated protein kinase (AMPK)/sirtuin 1 (SIRT1)/NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome axis. Our results showed that wogonin (20 mg/kg, intraperitoneal injection) effectively reduced infarct size, attenuated brain edema, improved neurological deficits, and alleviated histopathological damage. In addition, wogonin reduced microglial cell activation and inflammatory factors, including tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), IL-6, and IL-10, in brain tissue and serum after cerebral IR injury. Wogonin also effectively activated the AMPK/SIRT1 signaling pathway and inhibited NLPR3 inflammasome-related molecules upregulation in cerebral IR injury as well as in OGD/R-stimulated HT-22 cells. Furthermore, inhibition of the AMPK/SIRT1 signaling pathway by Compound C, an AMPK inhibitor, significantly reversed the protective effect of wogonin on OGD/R-induced NLRP3 inflammasome. Meanwhile, the protective effect of wogonin against brain IR injury was also reversed in the presence of compound C. These results suggest that wogonin ameliorates cerebral IR injruy-induced inflammation by inhibiting NLRP3 inflammasome through the AMPK/SIRT1 signaling pathway.

Review of the therapeutic potential of Forsythiae Fructus on the central nervous system: Active ingredients and mechanisms of action

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine has gained significant attention in recent years owing to its multi-component, multi-target, and multi-pathway advantages in treating various diseases. Forsythiae Fructus, derived from the dried fruit of Forsythia suspensa (Thunb.) Vahl, is one such traditional Chinese medicine with numerous in vivo and ex vivo therapeutic effects, including anti-inflammatory, antibacterial, and antiviral properties. Forsythiae Fructus contains more than 200 chemical constituents, with forsythiaside, forsythiaside A, forsythiaside B, isoforsythiaside, forsythin, and phillyrin being the most active ingredients. Forsythiae Fructus exerts neuroprotective effects by modulating various pathways, including oxidative stress, anti-inflammation, NF-κB signaling, 2-AG, Nrf2 signaling, acetylcholinesterase, PI3K-Akt signaling, ferroptosis, gut-brain axis, TLR4 signaling, endoplasmic reticulum stress, PI3K/Akt/mTOR signaling, and PPARγ signaling pathway.

AIM OF THE STUDY

This review aims to highlight the potential therapeutic effects of Forsythiae Fructus on the central nervous system and summarize the current knowledge on the active ingredients of Forsythiae Fructus and their effects on different pathways involved in neuroprotection.

MATERIALS AND METHODS

In this review, we conducted a comprehensive search of databases (PubMed, Google Scholar, Web of Science, China Knowledge Resource Integrated, local dissertations and books) up until June 2023 using key terms such as Forsythia suspensa, Forsythiae Fructus, forsythiaside, isoforsythiaside, forsythin, phillyrin, Alzheimer's disease, Parkinson's disease, ischemic stroke, intracerebral hemorrhage, traumatic brain injury, aging, and herpes simplex virus encephalitis.

RESULTS

Our findings indicate that Forsythiae Fructus and its active ingredients own therapeutic effects on the central nervous system by modulating various pathways, including oxidative stress, anti-inflammation, NF-κB signaling, 2-AG, Nrf2 signaling, acetylcholinesterase, PI3K-Akt signaling, ferroptosis, the gut-brain axis, TLR4 signaling, endoplasmic reticulum stress, PI3K/Akt/mTOR signaling, and PPARγ signaling pathway.

CONCLUSION

Forsythiae Fructus and its active ingredients have demonstrated promising neuroprotective properties. Future in vivo and clinical studies of Forsythiae Fructus and its active ingredients should be conducted to establish precise dosage and standard guidelines for a more effective application in the treatment of neurological disorders.

Supplementation with a Symbiotic Induced Neuroprotection and Improved Memory in Rats with Ischemic Stroke

After an ischemic stroke, various harmful mechanisms contribute to tissue damage, including the inflammatory response. The increase in pro-inflammatory cytokines has been related to greater damage to the neural tissue and the promotion of neurological alterations, including cognitive impairment. Recent research has shown that the use of prebiotics and/or probiotics counteracts inflammation and improves cognitive function through the production of growth factors, such as brain-derived neurotrophic factor (BDNF), by reducing inflammatory molecules. Therefore, in this study, the effect of the symbiotic inulin and Enterococcus faecium on neuroprotection and memory improvement was evaluated in a rat model of transient middle cerebral artery occlusion (tMCAO). In order to accomplish this, the animals were subjected to ischemia; the experimental group was supplemented with the symbiotic and the control group with the vehicle. The neurological deficit as well as spatial and working memory were evaluated using the Zea Longa scale, Morris water maze, and the eight-arm maze tests, respectively. Infarct size, the levels of BDNF, and tumor necrosis factor-alpha (TNF-α) were also assessed. The results show that supplementation with the symbiotic significantly diminished the neurological deficit and infarct size, improved memory and learning, increased BDNF expression, and reduced TNF-α production. These findings provide new evidence about the therapeutic use of symbiotics for ischemic stroke and open up the possibilities for the design of further studies.

A Promising Application of Injectable Hydrogels in Nerve Repair and Regeneration for Ischemic Stroke

Ischemic stroke, a condition that often leads to severe nerve damage, induces complex pathological and physiological changes in nerve tissue. The mature central nervous system (CNS) lacks intrinsic regenerative capacity, resulting in a poor prognosis and long-term neurological impairments. There is no available therapy that can fully restore CNS functionality. However, the utilization of injectable hydrogels has emerged as a promising strategy for nerve repair and regeneration. Injectable hydrogels possess exceptional properties, such as biocompatibility, tunable mechanical properties, and the ability to provide a supportive environment for cell growth and tissue regeneration. Recently, various hydrogel-based tissue engineering approaches, including cell encapsulation, controlled release of therapeutic factors, and incorporation of bioactive molecules, have demonstrated great potential in the treatment of CNS injuries caused by ischemic stroke. This article aims to provide a comprehensive review of the application and development of injectable hydrogels for the treatment of ischemic stroke-induced CNS injuries, shedding light on their therapeutic prospects, challenges, recent advancements, and future directions. Additionally, it will discuss the underlying mechanisms involved in hydrogel-mediated nerve repair and regeneration, as well as the need for further preclinical and clinical studies to validate their efficacy and safety.

Role of ATG7-dependent non-autophagic pathway in angiogenesis

ATG7, one of the core proteins of autophagy, plays an important role in various biological processes, including the regulation of autophagy. While clear that autophagy drives angiogenesis, the role of ATG7 in angiogenesis remains less defined. Several studies have linked ATG7 with angiogenesis, which has long been underappreciated. The knockdown of ATG7 gene in cerebrovascular development leads to angiogenesis defects. In addition, specific knockout of ATG7 in endothelial cells results in abnormal development of neovascularization. Notably, the autophagy pathway is not necessary for ATG7 regulation of angiogenesis, while the ATG7-dependent non-autophagic pathway plays a critical role in the regulation of neovascularization. In order to gain a better understanding of the non-autophagic pathway-mediated biological functions of the autophagy-associated protein ATG7 and to bring attention to this expanding but understudied research area, this article reviews recent developments in the ATG7-dependent non-autophagic pathways regulating angiogenesis.

Identification and characterization of biomarkers associated with endoplasmic reticulum protein processing in cerebral ischemia-reperfusion injury

Background

Cerebral ischemia (CI), ranking as the second leading global cause of death, is frequently treated by reestablishing blood flow and oxygenation. Paradoxically, this reperfusion can intensify tissue damage, leading to CI-reperfusion injury. This research sought to uncover biomarkers pertaining to protein processing in the endoplasmic reticulum (PER) during CI-reperfusion injury.

Methods

We utilized the Gene Expression Omnibus (GEO) dataset GSE163614 to discern differentially expressed genes (DEGs) and single out PER-related DEGs. The functions and pathways of these PER-related DEGs were identified via Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Core genes were pinpointed through protein-protein interaction (PPI) networks. Subsequent to this, genes with diagnostic relevance were distinguished using external validation datasets. A single-sample gene-set enrichment analysis (ssGSEA) was undertaken to pinpoint genes with strong associations to hypoxia and apoptosis, suggesting their potential roles as primary inducers of apoptosis in hypoxic conditions during ischemia-reperfusion injuries.

Results

Our study demonstrated that PER-related genes, specifically ADCY5, CAMK2A, PLCB1, NTRK2, and DLG4, were markedly down-regulated in models, exhibiting a robust association with hypoxia and apoptosis.

Conclusion

The data indicates that ADCY5, CAMK2A, PLCB1, NTRK2, and DLG4 could be pivotal genes responsible for triggering apoptosis in hypoxic environments during CI-reperfusion injury.

Netrin-1 protects blood-brain barrier (BBB) integrity after cerebral ischemia-reperfusion by activating the Kruppel-like factor 2 (KLF2)/occludin pathway

Ischemia/reperfusion (I/R)-induced neural damage and neuroinflammation have been associated with pathological progression during stroke. Netrin-1 is an important member of the family of laminin-related secreted proteins, which plays an important role in governing axon elongation. However, it is unknown whether Netrin-1 possesses a beneficial role in stroke. Here, we employed the middle cerebral artery occlusion (MCAO) model to study the function of Netrin-1 in alleviating brain injuries. Our results demonstrate that Netrin-1 rescued poststroke neurological deficits and inhibited production of the inflammatory cytokines such as interleukin 6 (IL-6) and endothelial chemokine (C-X-C motif) ligand 1 (Cxcl1). Importantly, Netrin-1 protected against MCAO-induced dysfunction of the blood-brain barrier (BBB) in mice and a reduction in the expression of the tight junction (TJ) protein occludin. Additionally, we report that Netrin-1 could ameliorate oxygen-glucose deprivation/reoxygenation (OGD/R)-induced injury and prevent aggravation in endothelial monolayer permeability in bEnd.3 human brain microvascular endothelial cells (HBMVECs). Mechanistically, Netrin-1 ameliorated OGD/R-induced decrease in occludin and Kruppel-like factor 2 (KLF2) in HBMVECs. Notably, silencing of KLF2 abolished the beneficial effects of Netrin-1 in protecting endothelial permeability and occludin expression, suggesting that these effects are mediated by KLF2. In conclusion, our findings suggest that Netrin-1 could constitute a novel therapeutic strategy for ischemic stroke.

Integrative analyses and validation of ferroptosis-related genes and mechanisms associated with cerebrovascular and cardiovascular ischemic diseases

BACKGROUND

There has been a gradual increase in the occurrence of cardiovascular and cerebrovascular ischemic diseases, particularly as comorbidities. Yet, the mechanisms underlying these diseases remain unclear. Ferroptosis has emerged as a potential contributor to cardio-cerebral ischemic processes. Therefore, this study investigated the shared biological mechanisms between the two processes, as well as the role of ferroptosis genes in cardio-cerebral ischemic damage, by constructing co-expression modules for myocardial ischemia (MI) and ischemic stroke (IS) and a network of protein-protein interactions, mRNA-miRNA, mRNA-transcription factors (TFs), mRNA-RNA-binding proteins (RBPs), and mRNA-drug interactions.

RESULTS

The study identified seven key genes, specifically ACSL1, TLR4, ADIPOR1, G0S2, PDK4, HP, PTGS2, and subjected them to functional enrichment analysis during ischemia. The predicted miRNAs were found to interact with 35 hub genes, and interactions were observed between 11 hub genes and 30 TF transcription factors. Additionally, 10 RBPs corresponding to 16 hub genes and 163 molecular compounds corresponding to 30 hub genes were identified. This study also clarified the levels of immune infiltration between MI and IS and different subtypes. Finally, we identified four hub genes, including TLR4, by using a diagnostic model constructed by Least Absolute Shrinkage and Selection Operator (LASSO) regression analysis; ADIPOR1, G0S2, and HP were shown to have diagnostic value for the co-pathogenesis of MI and cerebral ischemia by both validation test data and RT-qPCR assay.

CONCLUSIONS

To the best our knowledge, this study is the first to utilize multiple algorithms to comprehensively analyze the biological processes of MI and IS from various perspectives. The four hub genes, TLR4, ADIPOR1, G0S2, and HP, have proven valuable in offering insights for the investigation of shared injury pathways in cardio-cerebral injuries. Therefore, these genes may serve as diagnostic markers for cardio-cerebral ischemic diseases.

Tat-CCT2 Protects the Neurons from Ischemic Damage by Reducing Oxidative Stress and Activating Autophagic Removal of Damaged Protein in the Gerbil Hippocampus

CCT2 is a eukaryotic chaperonin TCP-1 ring complex subunit that mediates protein folding, autophagosome incorporation, and protein aggregation. In this study, we investigated the effects of CCT on oxidative and ischemic damage using in vitro and in vivo experimental models. The Tat-CCT2 fusion protein was efficiently delivered into HT22 cells in a concentration- and time-dependent manner, and the delivered protein was gradually degraded in HT22 cells. Incubation with Tat-CCT2 significantly ameliorated the 200 µM hydrogen peroxide (H2O2)-induced reduction in cell viability in a concentration-dependent manner, and 8 µM Tat-CCT2 treatment significantly alleviated H2O2-induced DNA fragmentation and reactive oxygen species formation in HT22 cells. In gerbils, CCT2 protein was efficiently delivered into pyramidal cells in CA1 region by intraperitoneally injecting 0.5 mg/kg Tat-CCT2, as opposed to control CCT2. In addition, treatment with 0.2 or 0.5 mg/kg Tat-CCT2 mitigated ischemia-induced hyperlocomotive activity 1 d after ischemia and confirmed the neuroprotective effects by NeuN immunohistochemistry in the hippocampal CA1 region 4 d after ischemia. Tat-CCT2 treatment significantly reduced the ischemia-induced activation of astrocytes and microglia in the hippocampal CA1 region 4 d after ischemia. Furthermore, treatment with 0.2 or 0.5 mg/kg Tat-CCT2 facilitated ischemia-induced autophagic activity and ameliorated ischemia-induced autophagic initiation in the hippocampus 1 d after ischemia based on western blotting for LC3B and Beclin-1, respectively. Levels of p62, an autophagic substrate, significantly increased in the hippocampus following treatment with Tat-CCT2. These results suggested that Tat-CCT2 exerts neuroprotective effects against oxidative stress and ischemic damage by promoting the autophagic removal of damaged proteins or organelles.

Electroacupuncture Alleviates Neuroinflammation by Regulating Microglia Polarization via STAT6/PPARγ in Ischemic Stroke Rats

Previous study showed that electroacupuncture (EA) produced a protective effect on cerebral ischemia-reperfusion injury (CIRI) in rats and may correlate with the anti-inflammatory effects of microglia. This study aimed to investigate further whether EA could modulate neuroinflammation by targeting the Signal Transducer and Activator of Transcription 6 (STAT6) and Peroxisome Proliferator-Activated Receptor γ (PPARγ) pathway, the key regulator of microglia. Middle cerebral artery occlusion (MCAO) rats were used, and 6 h after reperfusion, EA interventions were performed in Chize (LU 5), Hegu (LI 4), Sanyinjiao (SP 6), and Zusanli (ST 36) on the affected side of the rats, the group that received EA + STAT6 phosphorylation inhibitor AS1517499 was used as a parallel control. The degree of neurological impairment, infarct volume, microglia polarization, inflammation levels and activity of STAT6/PPARγ pathway were then assessed by neurological deficit score, triphenyl tetrazolium chloride (TTC) staining, immunofluorescence, western blotting (WB), quantitative real-time PCR (qPCR) and Enzyme linked immunosorbent assay (ELISA). The data showed that EA significantly alleviated nerve injury, reduced infarct volume, enhanced the expression and activity of STAT6/PPARγ pathway, inhibited NF-κB activity, increased M2 microglia numbers and anti-inflammatory factor release, and inhibited microglia M1-type polarization and pro-inflammatory factor expression. In contrast, inhibition of STAT6 phosphorylation exacerbated neural damage, inhibited STAT6/PPARγ pathway activity, promoted microglia M1-type polarization and exacerbated neuroinflammation, resulting in an attenuated positive effect of EA intervention. Therefore, we concluded that EA intervention could attenuate microglia-associated neuroinflammation by enhancing the expression and activity of STAT6/PPARγ pathway, thereby reducing CIRI in MCAO rats.

A Novel Role of ARA70 in Regulating Ferritinophagy of RGCs During Retinal Ischemia Reperfusion

Although the contribution of ferroptosis, an iron-dependent cell death, to ischemia reperfusion (IR)-induced retinal injury has been reported before, to optimize therapeutic strategy, there is still an urgent need to identify potential candidates involved in this process. Androgen Receptor-Associated Protein of 70 kDa (ARA70) is a cargo receptor for ferritinophagy, and its role in retinal ferroptosis has not been revealed yet. Herein, we explored the role of ARA70 in IR-associated retinal lesions by in vivo (C57BL/6 J mice with intraocular pressure of 90-100 mmHg) and in vitro (retinal ganglion cells (RGCs) stimulated with tert-butyl hydroperoxide (tBH)) experiments. It was found that IR upregulated ARA70 expression and accelerated lipid peroxidation in retinal tissues. We first confirmed that two ferroptosis inhibitors, deferiprone or ferrostatin-1 (Fer-1), suppressed ferritin degradation, restrained apoptosis and inflammation, and protected mouse retinas against IR stress. Next, primary mouse RGCs were treated with tBH to simulate IR environment in vitro. ARA70 expression was decreased at lower concentrations of tBH (5-20 μM), but increased at higher concentrations (40-80 μM). Interestingly, the expression of ferritin-related proteins (ferritin heavy chain, FTH; ferritin light chain, FTL) showed an opposite alteration. Knockdown of ARA70 protected RGCs from tBH-induced damage. It inhibited the delivery of ferritin to lysosomes for ferritinophagy and thus reducing cellular Fe2+ concentration. Besides, ARA70 knockdown suppressed autophagy and inflammation of tBH-treated RGCs. These findings provide novel insights into the pathogenesis of retinal IR, and may be helpful for treatment of retinal diseases.

Bone marrow mesenchymal stem cells-derived exosomes mediated delivery of tetramethylpyrazine attenuate cerebral ischemic injury

OBJECTIVES

Tetramethylpyrazine (TEP) can protect the brain from ischemic damage, but it has defects such as short half-life, fast absorption, wide distribution, and rapid elimination, which limits its application. Exosomes (Exos) have the property of loading drugs and transporting signal substances. Here, we elucidated the effect of TEP-loaded bone marrow mesenchymal stem cell (BMSC)-derived Exos (Exo-TEP) on cerebral ischemic injury.

MATERIALS AND METHODS

The Exos were extracted by ultracentrifugation and TEP was loaded into the Exos by electroporation. Oxygen-glucose deprivation (OGD) induced-primary cortical neurons and middle cerebral artery occlusion (MCAO)-induced mouse models were used to determine the effect of Exo-TEP on cerebral ischemic injury in vitro and in vivo.

RESULTS

Exo-TEP exhibited a stable and sustained release pattern compared to free TEP. Exo-TEP treatment was more significant in improving OGD-mediated decrease in cell activity, as well as a elevation in apoptosis and ROS production in cortical neurons. In comparison with Exo and free TEP treatment, Exo-TEP treatment significantly improved pathological changes, shrunk cerebral infarction volume, as well reduced neurological deficit scores and neuronal apoptosis, and oxidative stress.

CONCLUSIONS

Exo-TEP was superior to free TEP in improving cerebral ischemic injury by reducing neuronal apoptosis and oxidative stress.

Moxibustion ameliorates cerebral ischemia-reperfusion injury by regulating ferroptosis in rats

Moxibustion is an effective treatment for the clinical management of acute cerebral infarction. However, its exact mechanism of action is still not fully understood. This study aimed to investigate the protective effect of moxibustion on cerebral ischemia-reperfusion injury (CIRI) in rats. Middle cerebral artery occlusion/reperfusion (MCAO/R) was used to construct a CIRI rat model, all animals were randomly divided into four groups including sham operation group, MCAO/R group (MCAO/R), moxibustion therapy + MCAO/R (Moxi) and ferrostatin-1 + MCAO/R (Fer-1) group. In the Moxi group, moxibustion treatment was initiated 24 h after modeling, once a day for 30 mins each time for 7 days. Moreover, the Fer-1 group received intraperitoneal injections of Fer-1 12 h after modeling, once a day for a total of 7 days. The results showed that moxibustion could reduce nerve function damage and neuronal death. Additionally, moxibustion could reduce the production of lipid peroxides such as lipid peroxide, malondialchehyche and ACSL4 to regulate lipid metabolism, promote the production of glutathione and glutathione peroxidase 4 and reduce the expression of hepcidin by inhibiting the production of inflammatory factor interleukin-6, therefore, downregulating the expression of SLC40A1, reducing the iron level in the cerebral cortex, reducing the accumulation of reactive oxygen species and inhibiting ferroptosis. Based on our studies, it can be concluded that moxibustion has the ability to inhibit ferroptosis of nerve cells post CIRI and plays a protective role in the brain. This protective role can be attributed to the regulation of iron metabolism of nerve cells, reduction of iron deposition in the hippocampus and lowering the level of lipid peroxidation.

Potential Role of Natural Antioxidants in Countering Reperfusion Injury in Acute Myocardial Infarction and Ischemic Stroke

Stroke and acute myocardial infarction are leading causes of mortality worldwide. The latter accounts for approximately 9 million deaths annually. In turn, ischemic stroke is a significant contributor to adult physical disability globally. While reperfusion is crucial for tissue recovery, it can paradoxically exacerbate damage through oxidative stress (OS), inflammation, and cell death. Therefore, it is imperative to explore diverse approaches aimed at minimizing ischemia/reperfusion injury to enhance clinical outcomes. OS primarily arises from an excessive generation of reactive oxygen species (ROS) and/or decreased endogenous antioxidant potential. Natural antioxidant compounds can counteract the injury mechanisms linked to ROS. While promising preclinical results, based on monotherapies, account for protective effects against tissue injury by ROS, translating these models into human applications has yielded controversial evidence. However, since the wide spectrum of antioxidants having diverse chemical characteristics offers varied biological actions on cell signaling pathways, multitherapy has emerged as a valuable therapeutic resource. Moreover, the combination of antioxidants in multitherapy holds significant potential for synergistic effects. This study was designed with the aim of providing an updated overview of natural antioxidants suitable for preventing myocardial and cerebral ischemia/reperfusion injuries.

Mechanism of PGC-1α-mediated mitochondrial biogenesis in cerebral ischemia-reperfusion injury

Cerebral ischemia-reperfusion injury (CIRI) is a series of cascade reactions that occur after blood flow recanalization in the ischemic zone in patients with cerebral infarction, causing an imbalance in intracellular homeostasis through multiple pathologies such as increased oxygen free radicals, inflammatory response, calcium overload, and impaired energy metabolism, leading to mitochondrial dysfunction and ultimately apoptosis. Rescue of reversibly damaged neurons in the ischemic hemispheric zone is the key to saving brain infarction and reducing neurological deficits. Complex and active neurological functions are highly dependent on an adequate energy supply from mitochondria. Mitochondrial biogenesis (MB), a process that generates new functional mitochondria and restores normal mitochondrial function by replacing damaged mitochondria, is a major mechanism for maintaining intra-mitochondrial homeostasis and is involved in mitochondrial quality control to ameliorate mitochondrial dysfunction and thus protects against CIRI. The main regulator of MB is peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), which improves mitochondrial function to protect against CIRI by activating its downstream nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM) to promote mitochondrial genome replication and transcription. This paper provides a theoretical reference for the treatment of neurological impairment caused by CIRI by discussing the mechanisms of mitochondrial biogenesis during cerebral ischemia-reperfusion injury.

Enriched environment-induced neuroplasticity in ischemic stroke and its underlying mechanisms

Stroke is a common cerebrovascular disease that can interrupt local blood flow in the brain, causing neuronal damage or even death, resulting in varying degrees of neurological dysfunction. Neuroplasticity is an important neurological function that helps neurons reorganize and regain function after injury. After cerebral ischemia, neuroplasticity changes are critical factors for restoring brain function. An enriched environment promotes increased neuroplasticity, thereby aiding stroke recovery. In this review, we discuss the positive effects of the enriched environment on neuroplasticity after cerebral ischemia, including synaptic plasticity, neurogenesis, and angiogenesis. In addition, we also introduce some studies on the clinical application of enriched environments in the rehabilitation of post-stroke patients, hoping that they can provide some inspiration for doctors and therapists looking for new approaches to stroke rehabilitation.