Autophagy in ischemic stroke

The potential mechanism and clinical application value of remote ischemic conditioning in stroke

Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may be related to neuroinflammation, cellular immunity, apoptosis, and autophagy, the exact underlying molecular mechanisms are unclear. This review summarizes the current status of different types of remote ischemic conditioning methods in animal and clinical studies and analyzes their commonalities and differences in neuroprotective mechanisms and signaling pathways. Remote ischemic conditioning has emerged as a potential therapeutic approach for improving stroke-induced brain injury owing to its simplicity, non-invasiveness, safety, and patient tolerability. Different forms of remote ischemic conditioning exhibit distinct intervention patterns, timing, and application range. Mechanistically, remote ischemic conditioning can exert neuroprotective effects by activating the Notch1/phosphatidylinositol 3-kinase/Akt signaling pathway, improving cerebral perfusion, suppressing neuroinflammation, inhibiting cell apoptosis, activating autophagy, and promoting neural regeneration. While remote ischemic conditioning has shown potential in improving stroke outcomes, its full clinical translation has not yet been achieved.

Exosomes: the next-generation therapeutic platform for ischemic stroke

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional recovery. Therefore, there is an urgent need to develop new methods for the treatment of this condition. Exosomes are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological conditions. They have low immunogenicity, good stability, high delivery efficiency, and the ability to cross the blood-brain barrier. These physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic stroke. The rapid development of nanotechnology has advanced the application of engineered exosomes, which can effectively improve targeting ability, enhance therapeutic efficacy, and minimize the dosages needed. Advances in technology have also driven clinical translational research on exosomes. In this review, we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke, including their anti-inflammation, anti-apoptosis, autophagy-regulation, angiogenesis, neurogenesis, and glial scar formation reduction effects. However, it is worth noting that, despite their significant therapeutic potential, there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified exosomes. Future optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic stroke. Ultimately, our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

Simvastatin exerts neuroprotective effects post-stroke by ameliorating endoplasmic reticulum stress and regulating autophagy/apoptosis balance through pAMPK/LC3B/ LAMP2 axis

Statins have evident neuroprotective role in acute ischemic stroke(AIS). The pleiotropic effect by which statin exerts neuroprotective effects, needs to be explored for considering it as one of the future adjunctive therapies in AIS. Endoplasmic reticulum(ER) assists cellular survival by reducing protein aggregates during ischemic conditions. ER-stress mediated apoptosis and autophagy are predominant reasons for neuronal death in AIS. Statin exerts both anti-apoptotic and anti-autophagic effect in neurons under ischemic stress. Although the influence of statin on autophagic neuroprotection has been reported with contradictory results. Thus, in our study we have attempted to understand its influence on autophagic protection while inhibiting upregulation of autophagic death(autosis). Previously we reported, statin can alleviate apoptosis via modulating cardiolipin mediated mitochondrial dysfunction. However, the clearance of damaged mitochondria is essential for prolonged cell survival. In our study, we tried to decipher the mechanism by which statin leads to neuronal survival by the mitophagy mediated cellular clearance. Simvastatin was administered to Sprague Dawley(SD) rats both as prophylaxis and treatment. The safety and efficacy of the statin was validated by assessment of infarct size and functional outcome. A reduction in oxidative and ER-stress were observed in both the prophylactic and treatment groups. The influence of statin on autophagy/apoptosis balance was evaluated by molecular assessment of mitophagy and cellular apoptosis. Statin reduces the post-stroke ER-stress and predominantly upregulated autophagolysosome mediated mitophagy than apoptotic cell death by modulating pAMPK/LC3B/LAMP2 axis. Based on the above findings statin could be explored as an adjunctive therapy for AIS in future.

Atmospheric pressure plasma preconditioning reduces oxygen and glucose deprivation induced human neuronal SH-SY5Y cells apoptosis by activating protective autophagy and ROS/AMPK/mTOR pathway

Reactive oxygen species (ROS)/reactive nitrogen species (RNS) exert a "double edged" effect on the occurrence and development of ischemic stroke. We previously indicate that atmospheric pressure plasma (APP) shows a neuroprotective effect in vitro based on the ROS/RNS generations. However, the mechanism is still unknown. In this work, SH-SY5Y cells were treated with oxygen and glucose deprivation (OGD) injuries for stimulating the ischemic stroke pathological injury process. A helium APP was used for SH-SY5Y cell treatment for evaluating the neuroprotective impacts of APP preconditioning against OGD injuries with the optimized parameters. During the preconditioning, APP significantly raised the extracellular and intracellular ROS/RNS production. As a result, APP preconditioning increased SH-SY5Y cell autophagy by elevating LC3-II/LC3-I ratio and autophagosome formation. Meanwhile, APP preconditioning reduced cell apoptosis caused by OGD with the increased APP treatment time, which was abolished by pretreatment with autophagy inhibitor 3-methyladenine (3-MA). The ROS scavenger N-acetyl-L-cysteine (NAC) alone or combined with NO scavenger carboxy-PTIO abolished the APP preconditioning induced SH-SY5Y autophagy and the cytoprotection, whereas the NO scavenger alone did not. In addition, we observed the elevated phosphorylation of AMP-activated protein kinase (AMPK) and decreased phosphorylation of mammalian target of rapamycin (mTOR) in APP treated SH-SY5Y cells. This effect was attenuated by AMPK inhibitor Compound C (CC), the ROS scavenger NAC and autophagy inhibitor 3-MA. Furthermore, the cytoprotective effect of APP was preliminarily confirmed in the rats of middle cerebral artery occlusion (MCAO) model. Results showed that APP inhalation by rats during MCAO process could improve neurological functions, reduce cell apoptosis in brain tissues and decrease cerebral infarct volume. Our data suggested that ROS produced by APP preconditioning played a vital role in the neuroprotective effect of SH-SY5Y cells against OGD injuries by activating autophagy and ROS/AMPK/mTOR pathway.

4-Hydroxydictyolactone alleviates cerebral ischemia injury by regulating neuroinflammation and autophagy via AMPK signaling pathway

BACKGROUND

Cerebral ischemia (CI), a cerebrovascular disorder, is a major contributor to disability and mortality. Marine-derived compounds are an important source of new neuroprotective drug candidates. Xenicane-type diterpenes from brown algae of the genus Dictyota have exhibited potential neuroprotective effects against CI injury, attributed to their antioxidant properties. However, whether there are other underlying neuroprotective mechanisms of xenicane diterpenes against CI is still ambiguous.

PURPOSE

This study aims to elucidate the neuroprotective efficacy and mechanism of 4-hydroxydictyolactone (HDTL) in the treatment of CI.

METHODS

The LPS-induced BV2 cell model was used for anti-neuroinflammatory activity assay. Tandem Mass Tag (TMT)-based quantitative proteomics was employed to identify underlying mechanisms. The OGD/R-induced SH-SY5Y cell model and a MCAO mice model were used to assess the neuroprotective effect of HDTL against CI in vitro and in vivo.

RESULTS

HDTL reduced inflammation in LPS-stimulated BV2 cells by inhibiting the IKK/IκB/NF-κB pathway and by enhancing AMPK phosphorylation. Additionally, in SH-SY5Y cells treated with OGD/R, HDTL facilitated autophagy and reduced apoptosis. The neuroprotective properties of HDTL were abrogated in AMPK- silenced SH-SY5Y cells. In MCAO mice, HDTL ameliorated CI injury as evidenced by decreases in neurological deficit scores and cerebral infarction. HDTL also promoted autophagy and reduced apoptosis in vivo through both the AMPK/mTOR and IKK/IκB/NF-κB pathways.

CONCLUSION

HDTL exhibits neuroprotective effects through regulating the AMPK/mTOR and IKK/IκB/NF-κB pathways. These findings suggest that HDTL is a promising therapeutic candidate for CI treatment.

Autophagy and its role in gastrointestinal diseases

Gastrointestinal disorders encompass a spectrum of conditions affecting various organs within the digestive system, such as the esophagus, stomach, colon, rectum, pancreas, liver, small intestine, and bile ducts. The role of autophagy in the etiology and progression of gastrointestinal diseases has garnered significant attention. This paper seeks to evaluate the impact and mechanisms of autophagy in gastrointestinal disorders by synthesizing recent research findings. Specifically, we delve into inflammation-related gastrointestinal conditions, including ul-cerative colitis, Crohn's disease, and pancreatitis, as well as gastrointestinal cancers such as esophageal, gastric, and colorectal cancers. Additionally, we provide commentary on a recent publication by Chang et al in the World Journal of Gastroenterology. Our objective is to offer fresh perspectives on the mechanisms and therapeutic approaches for these gastrointestinal ailments. This review aims to offer new perspectives on the mechanisms and therapeutic strategies for gastrointestinal disorders by critically analyzing relevant publications. As discussed, the role of autophagy in gastrointestinal diseases is complex and, at times, contentious. To harness the full therapeutic potential of autophagy in treating these conditions, more in-depth research is imperative.

DJ-1 regulates astrocyte activation through miR-155/SHP-1 signaling in cerebral ischemia/reperfusion injury

Reactive astrocyte activation in the context of cerebral ischemia/reperfusion (I/R) injury gives rise to two distinct subtypes: the neurotoxic A1 type and the neuroprotective A2 type. DJ-1 (Parkinson disease protein 7, PARK7), originally identified as a Parkinson's disease-associated protein, is a multifunctional anti-oxidative stress protein with molecular chaperone and signaling functions. SHP-1 (Src homology 2 domain-containing phosphatase-1) is a protein tyrosine phosphatase closely associated with cellular signal transduction. miR-155 is a microRNA that participates in cellular functions by regulating gene expression. Recent studies have uncovered the relationship between DJ-1 and astrocyte-mediated neuroprotection, which may be related to its antioxidant properties and regulation of signaling molecules such as SHP-1. Furthermore, miR-155 may exert its effects by influencing SHP-1, providing a potential perspective for understanding the molecular mechanisms of stroke. A middle cerebral artery occlusion/reperfusion (MCAO/R) model and an oxygen-glucose deprivation/reperfusion (OGD/R) model were established to simulate focal cerebral I/R injury in vivo and in vitro, respectively. The in vivo interaction between DJ-1 and SHP-1 has been experimentally validated through immunoprecipitation. Overexpression of DJ-1 attenuates I/R injury and suppresses miR-155 expression. In addition, inhibition of miR-155 upregulates SHP-1 expression and modulates astrocyte activation phenotype. These findings suggest that DJ-1 mediates astrocyte activation via the miR-155/SHP-1 pathway, playing a pivotal role in the pathogenesis of cerebral ischemia-reperfusion injury. Our results provide a potential way for exploring the pathogenesis of ischemic stroke and present promising targets for pharmacological intervention.

Src inhibition rescues FUNDC1-mediated neuronal mitophagy in ischaemic stroke

BACKGROUND

Ischaemic stroke triggers neuronal mitophagy, while the involvement of mitophagy receptors in ischaemia/reperfusion (I/R) injury-induced neuronal mitophagy remain not fully elucidated. Here, we aimed to investigate the involvement of mitophagy receptor FUN14 domain-containing 1 (FUNDC1) and its modulation in neuronal mitophagy induced by I/R injury.

METHODS

Wild-type and FUNDC1 knockout mice were generated to establish models of neuronal I/R injury, including transient middle cerebral artery occlusion (tMCAO) in vivo and oxygen glucose deprivation/reperfusion in vitro. Stroke outcomes of mice with two genotypes were assessed. Neuronal mitophagy was analysed both in vivo and in vitro. Activities of FUNDC1 and its regulator Src were evaluated. The impact of Src on FUNDC1-mediated mitophagy was assessed through administration of Src antagonist PP1.

RESULTS

To our surprise, FUNDC1 knockout mice subjected to tMCAO showed stroke outcomes comparable to those of their wild-type littermates. Although neuronal mitophagy could be activated by I/R injury, FUNDC1 deletion did not disrupt neuronal mitophagy. Transient activation of FUNDC1, represented by dephosphorylation of Tyr18, was detected in the early stages (within 3 hours) of neuronal I/R injury; however, phosphorylated Tyr18 reappeared and even surpassed baseline levels in later stages (after 6 hours), accompanied by a decrease in FUNDC1-light chain 3 interactions. Spontaneous inactivation of FUNDC1 was associated with Src activation, represented by phosphorylation of Tyr416, which changed in parallel with the level of phosphorylated FUNDC1 (Tyr18) during neuronal I/R injury. Finally, FUNDC1-mediated mitophagy in neurons under I/R conditions can be rescued by pharmacological inhibition of Src.

CONCLUSIONS

FUNDC1 is inactivated by Src during the later stage (after 6 hours) of neuronal I/R injury, and rescue of FUNDC1-mediated mitophagy may serve as a potential therapeutic strategy for treating ischaemic stroke.

Phytochemistry of Genus Buxus and Pharmacology of Cyclovirobuxine D

BACKGROUND

Genus Buxus plants, commonly known as "boxwood", are widely distributed in China. The stems, branches, and leaves of the plant are traditionally used for rheumatism, toothache, chest pain, abdominal gas, and other diseases. However, an overview of the genus Buxus remains to be provided.

PURPOSE

To provide a scientific basis for the appropriate use and further research the recent advancements in the traditional usage, phytochemistry, and, pharmacology of Buxus.

STUDY DESIGN

Chemical composition and pharmacological correlation studies through a literature review.

METHODS

Between 1970 and 2023, the available data concerning Buxus was compiled from online scientific sources, such as Sci-Finder, PubMed, CNKI, Google Scholar, and the Chinese Pharmacopoeia. Plant names were verified from "The Plant List" (http://www.theplantlist.org/).

RESULTS

To date, 266 structurally diverse chemicals have been extracted and identified from the genus Buxus. Alkaloids constitute one of its primary bioactive phytochemicals. A summary of the channels of action of Cyclovirobuxine D on the cytotoxicity of a variety of cancers has been provided.

CONCLUSION

Numerous findings from contemporary phytochemical and pharmacological studies support the traditional use, facilitating its application. Further research is necessary to address various shortcomings, including the identification of the active ingredients and quality control of the genus Buxus.

High-frequency repetitive transcranial magnetic stimulation promotes neural stem cell proliferation after ischemic stroke

JOURNAL/nrgr/04.03/01300535-202408000-00031/figure1/v/2023-12-16T180322Z/r/image-tiff Proliferation of neural stem cells is crucial for promoting neuronal regeneration and repairing cerebral infarction damage. Transcranial magnetic stimulation (TMS) has recently emerged as a tool for inducing endogenous neural stem cell regeneration, but its underlying mechanisms remain unclear. In this study, we found that repetitive TMS effectively promotes the proliferation of oxygen-glucose deprived neural stem cells. Additionally, repetitive TMS reduced the volume of cerebral infarction in a rat model of ischemic stroke caused by middle cerebral artery occlusion, improved rat cognitive function, and promoted the proliferation of neural stem cells in the ischemic penumbra. RNA-sequencing found that repetitive TMS activated the Wnt signaling pathway in the ischemic penumbra of rats with cerebral ischemia. Furthermore, PCR analysis revealed that repetitive TMS promoted AKT phosphorylation, leading to an increase in mRNA levels of cell cycle-related proteins such as Cdk2 and Cdk4. This effect was also associated with activation of the glycogen synthase kinase 3β/β-catenin signaling pathway, which ultimately promotes the proliferation of neural stem cells. Subsequently, we validated the effect of repetitive TMS on AKT phosphorylation. We found that repetitive TMS promoted Ca2+ influx into neural stem cells by activating the P2 calcium channel/calmodulin pathway, thereby promoting AKT phosphorylation and activating the glycogen synthase kinase 3β/β-catenin pathway. These findings indicate that repetitive TMS can promote the proliferation of endogenous neural stem cells through a Ca2+ influx-dependent phosphorylated AKT/glycogen synthase kinase 3β/β-catenin signaling pathway. This study has produced pioneering results on the intrinsic mechanism of repetitive TMS to promote neural function recovery after ischemic stroke. These results provide a strong scientific foundation for the clinical application of repetitive TMS. Moreover, repetitive TMS treatment may not only be an efficient and potential approach to support neurogenesis for further therapeutic applications, but also provide an effective platform for the expansion of neural stem cells.

Gasdermin D could be lost in the brain parenchyma infarct core and a pyroptosis-autophagy inhibition effect of Jie-Du-Huo-Xue decoction after stroke

Background

The Chinese ethnic medicine Jie-Du-Huo-Xue Decoction (JDHXD) is used to alleviate neuroinflammation in cerebral ischemia (CI). Our previous studies have confirmed that JDHXD can inhibit microglial pyroptosis in CI. However, the pharmacological mechanism of JDHXD in alleviating neuroinflammation and pyroptosis needs to be further elucidated. New research points out that there is an interaction between autophagy and inflammasome NLRP3, and autophagy can help clear NLRP3. The NLRP3 is a key initiator of pyroptosis and autophagy. The effect of JDHXD promoting autophagy to clear NLRP3 to inhibit pyroptosis on cerebral ischemia-reperfusion inflammatory injury is currently unknown. We speculate that JDHXD can inhibit pyroptosis in CI by promoting autophagy to clear NLRP3.

Methods

Chemical characterization of JDHXD was performed using LC-MS. Model of middle cerebral artery occlusion/reperfusion (MCAO/R) was established in SD rats. Neurological deficits, neuron damage, and cerebral infarct volume were evaluated. Western Blot and immunofluorescence were used to detect neuronal pyroptosis and autophagy.

Results

30 possible substance metabolites in JDHXD medicated serum were analyzed by LC-MS (Composite Score > 0.98). Furthermore, JDHXD protects rat neurological function and cerebral infarct size after CI. JDHXD inhibited the expression of pyroptosis and autophagy after CI. Our western blot and immunofluorescence results showed that JDHXD treatment can reduce the expression of autophagy-related factors ULK1, beclin1, and LC3-Ⅱ. The expression of NLRP3 protein was lower in the JDHXD group than in the I/R group. Compared with the I/R group, the expressions of pyroptosis-related factors caspase-1 P 10, GSDMD-NT, IL-18, and IL-1β decreased in the JDHXD group. Furthermore, we observed an unexpected result: immunofluorescence demonstrated that Gasdermin D (GSDMD) was significantly absent in the infarct core, and highly expressed in the peri-infarct and contralateral cerebral hemispheres. This finding challenges the prevailing view that GSDMD is elevated in the ischemic cerebral hemisphere.

Conclusion

JDHXD inhibited pyroptosis and autophagy after MCAO/R. JDHXD suppressed pyroptosis and autophagy by inhibiting NLRP3, thereby alleviating CI. In addition, we present a different observation from previous studies that the expression of GSDMD in the infarct core was lower than that in the peri-infarct and contralateral non-ischemic hemispheres on day 3 of CI.

Astrocytic autophagy plasticity modulates Aβ clearance and cognitive function in Alzheimer's disease

BACKGROUND

Astrocytes, one of the most resilient cells in the brain, transform into reactive astrocytes in response to toxic proteins such as amyloid beta (Aβ) in Alzheimer's disease (AD). However, reactive astrocyte-mediated non-cell autonomous neuropathological mechanism is not fully understood yet. We aimed our study to find out whether Aβ-induced proteotoxic stress affects the expression of autophagy genes and the modulation of autophagic flux in astrocytes, and if yes, how Aβ-induced autophagy-associated genes are involved Aβ clearance in astrocytes of animal model of AD.

METHODS

Whole RNA sequencing (RNA-seq) was performed to detect gene expression patterns in Aβ-treated human astrocytes in a time-dependent manner. To verify the role of astrocytic autophagy in an AD mouse model, we developed AAVs expressing shRNAs for MAP1LC3B/LC3B (LC3B) and Sequestosome1 (SQSTM1) based on AAV-R-CREon vector, which is a Cre recombinase-dependent gene-silencing system. Also, the effect of astrocyte-specific overexpression of LC3B on the neuropathology in AD (APP/PS1) mice was determined. Neuropathological alterations of AD mice with astrocytic autophagy dysfunction were observed by confocal microscopy and transmission electron microscope (TEM). Behavioral changes of mice were examined through novel object recognition test (NOR) and novel object place recognition test (NOPR).

RESULTS

Here, we show that astrocytes, unlike neurons, undergo plastic changes in autophagic processes to remove Aβ. Aβ transiently induces expression of LC3B gene and turns on a prolonged transcription of SQSTM1 gene. The Aβ-induced astrocytic autophagy accelerates urea cycle and putrescine degradation pathway. Pharmacological inhibition of autophagy exacerbates mitochondrial dysfunction and oxidative stress in astrocytes. Astrocyte-specific knockdown of LC3B and SQSTM1 significantly increases Aβ plaque formation and GFAP-positive astrocytes in APP/PS1 mice, along with a significant reduction of neuronal marker and cognitive function. In contrast, astrocyte-specific overexpression of LC3B reduced Aβ aggregates in the brain of APP/PS1 mice. An increase of LC3B and SQSTM1 protein is found in astrocytes of the hippocampus in AD patients.

CONCLUSIONS

Taken together, our data indicates that Aβ-induced astrocytic autophagic plasticity is an important cellular event to modulate Aβ clearance and maintain cognitive function in AD mice.

Advancing stroke therapy: innovative approaches with stem cell-derived extracellular vesicles

Stroke is a leading cause of mortality and long-term disability globally, with acute ischemic stroke (AIS) being the most common subtype. Despite significant advances in reperfusion therapies, their limited time window and associated risks underscore the necessity for novel treatment strategies. Stem cell-derived extracellular vesicles (EVs) have emerged as a promising therapeutic approach due to their ability to modulate the post-stroke microenvironment and facilitate neuroprotection and neurorestoration. This review synthesizes current research on the therapeutic potential of stem cell-derived EVs in AIS, focusing on their origin, biogenesis, mechanisms of action, and strategies for enhancing their targeting capacity and therapeutic efficacy. Additionally, we explore innovative combination therapies and discuss both the challenges and prospects of EV-based treatments. Our findings reveal that stem cell-derived EVs exhibit diverse therapeutic effects in AIS, such as promoting neuronal survival, diminishing neuroinflammation, protecting the blood-brain barrier, and enhancing angiogenesis and neurogenesis. Various strategies, including targeting modifications and cargo modifications, have been developed to improve the efficacy of EVs. Combining EVs with other treatments, such as reperfusion therapy, stem cell transplantation, nanomedicine, and gut microbiome modulation, holds great promise for improving stroke outcomes. However, challenges such as the heterogeneity of EVs and the need for standardized protocols for EV production and quality control remain to be addressed. Stem cell-derived EVs represent a novel therapeutic avenue for AIS, offering the potential to address the limitations of current treatments. Further research is needed to optimize EV-based therapies and translate their benefits to clinical practice, with an emphasis on ensuring safety, overcoming regulatory hurdles, and enhancing the specificity and efficacy of EV delivery to target tissues.

Research progress and challenges of stem cell therapy for ischemic stroke

Ischemic stroke is a significant global cause of death and disability. Currently, treatment options for acute ischemic stroke are limited to intravenous thrombolysis and mechanical recanalization. Therefore, novel neuroprotective strategies are imperative. Stem cell transplantation possesses the capabilities of differentiation, proliferation, neuronal replacement, nerve pathway reconstruction, secretion of nerve growth factors, and enhancement of the microenvironment; thus, it is a potential therapeutic approach for ischemic stroke. In addition, the immunomodulatory function of stem cells and the combined treatment of stem cells and exosomes exhibit a favorable protective effect on brain injury and neurological dysfunction following stroke. Meanwhile, the theory of microbiota-gut-brain axis provides us with a novel perspective for comprehending and managing neurological diseases. Lastly, stem cell transplantation has demonstrated promising outcomes not only in treating ischemic stroke but also in dealing with other neurological disorders, such as brain tumors. Furthermore, challenges related to the tissue source, delivery method, immune response, and timing of transplantation still need to be addressed to optimize the treatment.

LncRNA MALAT1 and Ischemic Stroke: Pathogenesis and Opportunities

Ischemic stroke (IS) stands as a prominent cause of mortality and long-term disability around the world. It arises primarily from a disruption in cerebral blood flow, inflicting severe neural injuries. Hence, there is a pressing need to comprehensively understand the intricate mechanisms underlying IS and identify novel therapeutic targets. Recently, long noncoding RNAs (lncRNAs) have emerged as a novel class of regulatory molecules with the potential to attenuate pathogenic mechanisms following IS. Among these lncRNAs, MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) has been extensively studied due to its involvement in the pathophysiological processes of IS. In this review, we provide an in-depth analysis of the essential role of MALAT1 in the development and progression of both pathogenic and protective mechanisms following IS. These mechanisms include oxidative stress, neuroinflammation, cell death signaling, blood brain barrier dysfunction, and angiogenesis. Furthermore, we summarize the impact of MALAT1 on the susceptibility and severity of IS. This review highlights the potential risks associated with the therapeutic use of MALAT1 for IS, which are attributable to the stimulatory action of MALAT1 on ischemia/reperfusion injury. Ultimately, this review sheds light on the potential molecular mechanisms and associated signaling pathways underlying MALAT1 expression post-IS, with the aim of uncovering potential therapeutic targets.

Metabolomic discoveries for early diagnosis and traditional Chinese medicine efficacy in ischemic stroke

Ischemic stroke (IS), a devastating cerebrovascular accident, presents with high mortality and morbidity. Following IS onset, a cascade of pathological changes, including excitotoxicity, inflammatory damage, and blood-brain barrier disruption, significantly impacts prognosis. However, current clinical practices struggle with early diagnosis and identifying these alterations. Metabolomics, a powerful tool in systems biology, offers a promising avenue for uncovering early diagnostic biomarkers for IS. By analyzing dynamic metabolic profiles, metabolomics can not only aid in identifying early IS biomarkers but also evaluate Traditional Chinese Medicine (TCM) efficacy and explore its mechanisms of action in IS treatment. Animal studies demonstrate that TCM interventions modulate specific metabolite levels, potentially reflecting their therapeutic effects. Identifying relevant metabolites in cerebral ischemia patients holds immense potential for early diagnosis and improved outcomes. This review focuses on recent metabolomic discoveries of potential early diagnostic biomarkers for IS. We explore variations in metabolites observed across different ages, genders, disease severity, and stages. Additionally, the review examines how specific TCM extracts influence IS development through metabolic changes, potentially revealing their mechanisms of action. Finally, we emphasize the importance of integrating metabolomics with other omics approaches for a comprehensive understanding of IS pathophysiology and TCM efficacy, paving the way for precision medicine in IS management.

β-elemene promotes microglial M2-like polarization against ischemic stroke via AKT/mTOR signaling axis-mediated autophagy

BACKGROUND

Resident microglia- and peripheric macrophage-mediated neuroinflammation plays a predominant role in the occurrence and development of ischemic stroke. Microglia undergo polarization to M1/M2-like phenotype under stress stimulation, which mediates intracellular inflammatory response. β-elemene is a natural sesquiterpene and possesses potent anti-inflammatory activity. This study aimed to investigate the anti-inflammatory efficacy and mechanism of β-elemene in ischemic stroke from the perspective of balancing microglia M1/M2-like polarization.

METHODS

The middle cerebral artery occlusion (MCAO) model and photothrombotic stroke model were established to explore the regulation effect of β-elemene on the cerebral ischemic injury. The LPS and IFN-γ stimulated BV-2 cells were used to demonstrate the anti-inflammatory effects and potential mechanism of β-elemene regulating M1/M2-like polarization in vitro.

RESULTS

In C57BL/6 J mice subjected to MCAO model and photothrombotic stroke model, β-elemene attenuated neurological deficit, reduced the infarction volume and neuroinflammation, thus improving ischemic stroke injury. β-elemene promoted the phenotype transformation of microglia from M1-like to M2-like, which prevented neurons from oxygen and glucose deprivation/reoxygenation (OGD/R) injury by inhibiting inflammatory factor release, thereby reducing neuronal apoptosis. Mechanically, β-elemene prevented the activation of TLR4/NF-κΒ and MAPK signaling pathway and increased AKT/mTOR mediated-autophagy, thereby promoting M2-like polarization of microglia.

CONCLUSIONS

These results indicated that β-elemene improved cerebral ischemic injury and promoted the transformation of microglia phenotype from M1-like to M2-like, at least in part, through AKT/mTOR-mediated autophagy. This study demonstrated that β-elemene might serve as a promising drug for alleviating ischemic stroke injury.

The role of LncRNA-mediated autophagy in cancer progression

Long non-coding RNAs (lncRNAs) are a sort of transcripts that are more than 200 nucleotides in length. In recent years, many studies have revealed the modulatory role of lncRNAs in cancer. Typically, lncRNAs are linked to a variety of essential events, such as apoptosis, cellular proliferation, and the invasion of malignant cells. Simultaneously, autophagy, an essential intracellular degradation mechanism in eukaryotic cells, is activated to respond to multiple stressful circumstances, for example, nutrient scarcity, accumulation of abnormal proteins, and organelle damage. Autophagy plays both suppressive and promoting roles in cancer. Increasingly, studies have unveiled how dysregulated lncRNAs expression can disrupt autophagic balance, thereby contributing to cancer progression. Consequently, exploring the interplay between lncRNAs and autophagy holds promising implications for clinical research. In this manuscript, we methodically compiled the advances in the molecular mechanisms of lncRNAs and autophagy and briefly summarized the implications of the lncRNA-mediated autophagy axis.

Crocetin protects mouse brain from apoptosis in traumatic brain injury model through activation of autophagy

BACKGROUND

Autophagy is recognized as a promising therapeutic target for traumatic brain injury (TBI). Crocetin is an aglycone of crocin naturally occurring in saffron and has been found to alleviate brain injury diseases. However, whether crocetin affects autophagy after TBI remains unknown. Therefore, we explore crocetin roles in autophagy after TBI.

METHODS

We used a weight-dropped model to induce TBI in C57BL/6J mice. Neurological severity scoring (NSS) and grip tests were used to evaluate the neurological level of injury. Brain edema, neuronal apoptosis, neuroinflammation and autophagy were detected by measurements of brain water content, TUNEL staining, ELISA kits and western blotting.

RESULTS

Crocetin ameliorated neurological dysfunctions and brain edema after TBI. Crocetin reduced neuronal apoptosis and neuroinflammation and enhanced autophagy after TBI.

CONCLUSION

Crocetin alleviates TBI by inhibiting neuronal apoptosis and neuroinflammation and activating autophagy.

The neuroprotective effect of Chinese herbal medicine for cerebral ischemia reperfusion injury through regulating mitophagy

The incidence of ischemic stroke has been increasing annually with an unfavorable prognosis. Cerebral ischemia reperfusion injury can exacerbate nerve damage. Effective mitochondrial quality control including mitochondrial fission, fusion and autophagy, is crucial for maintaining cellular homeostasis. Several studies have revealed the critical role of mitophagy in Cerebral ischemia reperfusion injury. Cerebral ischemia and hypoxia induce mitophagy, and mitophagy exhibits positive and negative effects in cerebral ischemia reperfusion injury. Studies have shown that Chinese herbal medicine can alleviate Cerebral ischemia reperfusion injury and serve as a neuroprotective agent by inhibiting or promoting mitophagy-mediated pathways. This review focuses on the mitochondrial dynamics and mitophagy-related pathways, as well as the role of mitophagy in ischemia reperfusion injury. Additionally, it discusses the therapeutic potential and benefits of Chinese herbal monomers and decoctions in the treatment of ischemic stroke.

Nanotherapeutics targeting autophagy regulation for improved cancer therapy

The clinical efficacy of current cancer therapies falls short, and there is a pressing demand to integrate new targets with conventional therapies. Autophagy, a highly conserved self-degradation process, has received considerable attention as an emerging therapeutic target for cancer. With the rapid development of nanomedicine, nanomaterials have been widely utilized in cancer therapy due to their unrivaled delivery performance. Hence, considering the potential benefits of integrating autophagy and nanotechnology in cancer therapy, we outline the latest advances in autophagy-based nanotherapeutics. Based on a brief background related to autophagy and nanotherapeutics and their impact on tumor progression, the feasibility of autophagy-based nanotherapeutics for cancer treatment is demonstrated. Further, emerging nanotherapeutics developed to modulate autophagy are reviewed from the perspective of cell signaling pathways, including modulation of the mammalian target of rapamycin (mTOR) pathway, autophagy-related (ATG) and its complex expression, reactive oxygen species (ROS) and mitophagy, interference with autophagosome-lysosome fusion, and inhibition of hypoxia-mediated autophagy. In addition, combination therapies in which nano-autophagy modulation is combined with chemotherapy, phototherapy, and immunotherapy are also described. Finally, the prospects and challenges of autophagy-based nanotherapeutics for efficient cancer treatment are envisioned.

Neuroprotective effect of apelin-13 and other apelin forms-a review

Neurodegenerative diseases, which occur when neurons begin to deteriorate, affect millions of people worldwide. These age-related disorders are becoming more common partly because the elderly population has increased in recent years. While no treatments are accessible, every year an increasing number of therapeutic and supportive options become available. Various substances that may have neuroprotective effects are currently being researched. One of them is apelin. This review aims to illustrate the results of research on the neuroprotective effect of apelin amino acid oligopeptide which binds to the apelin receptor and exhibits neuroprotective effects in the central nervous system. The collected data indicate that apelin can protect the central nervous system against injury by several mechanisms. More studies are needed to thoroughly investigate the potential neuroprotective effects of this peptide in neurodegenerative diseases and various other types of brain damage.

Oxidative medicine and cellular longevity the role and mechanism of NCOA4 in ferroptosis induced by intestinal ischemia reperfusion

BACKGROUND

Ferroptosis is an iron-dependent and cystathione-non-dependent non-apoptotic cell death characterized by elevated intracellular free iron levels and reduced antioxidant capacity, leading to the accumulation of lipid peroxides. Nuclear receptor coactivator 4 (NCOA4) mediates ferritinophagy, increasing labile iron levels, which can result in oxidative damage. However, the specific mechanism of NCOA4-mediated ferritinophagy in intestinal ischemia-reperfusion and the underlying mechanisms have not been reported in detail.

OBJECT

1. To investigate the role of NCOA4 in ferroptosis of intestinal epithelial cells induced by II/R injury in mouse. 2. To investigate the mechanism of action of NCOA4-induced ferroptosis.

METHODS

1. Construct a mouse II/R injury model and detect ferroptosis related markers such as HE staining, immunohistochemistry, ELISA, and WB methods. 2. Detect expression of NCOA4 in the intestine of mouse with II/R injury model and analyze its correlation with intestinal ferroptosis in mouse with II/R injury model. 3. Construct an ischemia-reperfusion model at the cellular level through hypoxia and reoxygenation, and overexpress/knockdown NCOA4 to detect markers related to ferroptosis. Based on animal experimental results, analyze the correlation and mechanism of action between NCOA4 and intestinal epithelial ferroptosis induced by II/R injury in mouse.

RESULTS

1. Ferroptosis occurred in the intestinal epithelial cells of II/R-injured mouse, and the expression of critical factors of ferroptosis, ACSL4, MDA and 15-LOX, was significantly increased, while the levels of GPX4 and GSH were significantly decreased. 2. The expression of NCOA4 in the intestinal epithelium of mouse with II/R injure was significantly increased, the expression of ferritin was significantly decreased, and the level of free ferrous ions was significantly increased; the expression of autophagy-related proteins LC3 and Beclin-1 protein was increased, and the expression of P62 was decreased, and these changes were reversed by autophagy inhibitors. 3. Knockdown of NCOA4 at the cellular level resulted in increased ferritin expression and decreased ferroptosis, and CO-IP experiments suggested that NCOA4 can bind to ferritin, which suggests that NCOA4 most likely mediates ferritinophagy to induce ferroptosis.

CONCLUSION

This thesis explored the role of NCOA4 in II/R injury in mice and the mechanism of action. The research results suggest that NCOA4 can mediate ferritinophagy to induce ferroptosis during II/R injury. This experiment reveals the pathological mechanism of II/R injury and provides some scientific basis for the development of drugs for the treatment of II/R injury based on the purpose of alleviating ferroptosis.

Polydopamine-modified black phosphorus nanosheet drug delivery system for the treatment of ischemic stroke

Black phosphorus (BP), as a representative metal-free semiconductor, has been extensively explored. It has a higher drug loading capacity in comparison to conventional materials and also possesses excellent biocompatibility and biodegradability. Furthermore, BP nanosheets can enhance the permeability of the blood-brain barrier (BBB) upon near-infrared (NIR) irradiation, owing to their photothermal effect. However, the inherent instability of BP poses a significant limitation, highlighting the importance of surface modification to enhance its stability. Ischemic stroke (IS) is caused by the occlusion of blood vessels, and its treatment is challenging due to the hindrance caused by the BBB. Therefore, there is an urgent need to identify improved methods for bypassing the BBB for more efficient IS treatment. This research devised a novel drug delivery approach based on pterostilbene (Pte) supported by BP nanosheets, modified with polydopamine (PDA) to form BP-Pte@PDA. This system shows robust stability and traverses the BBB using effective photothermal mechanisms. This enables the release of Pte upon pH and NIR stimuli, offering potential therapeutic advantages for treating IS. In a middle cerebral artery occlusion mouse model, the BP-Pte@PDA delivery system significantly reduced infarct size, and brain water content, improved neurological deficits, reduced the TLR4 inflammatory factor expression, and inhibited cell apoptosis. In summary, the drug delivery system fabricated in this study thus demonstrated good stability, therapeutic efficacy, and biocompatibility, rendering it suitable for clinical application.

Simultaneously Monitoring Multiple Autophagic Processes and Assessing Autophagic Flux in Single Cells by In Situ Fluorescence Cross-Correlation Spectroscopy

Autophagy is a widely conserved and multistep cellular catabolic process and maintains cellular homeostasis and normal cellular functions via the degradation of some harmful intracellular components. It was reported that high basal autophagic activity may be closely related to tumorigenesis. So far, the fluorescence imaging technique has been widely used to study autophagic processes, but this method is only suitable for distinguishing autophagosomes and autolysosomes. Simultaneously monitoring multiple autophagic processes remains a significant challenge due to the lack of an efficient detection method. Here, we demonstrated a new method for simultaneously monitoring multiple autophagic processes and assessing autophagic flux in single cells based on in situ fluorescence cross-correlation spectroscopy (FCCS). In this study, microtubule-associated protein 1A/1B-light chain 3B (LC3B) was fused with two tandem fluorescent proteins [mCherry red fluorescent protein (mCherry) and enhanced green fluorescent protein (EGFP)] to achieve the simultaneous labeling and distinguishing of multiple autophagic structures based on the differences in characteristic diffusion time (τD). Furthermore, we proposed a new parameter "delivery efficiency of autophagosome (DEAP)" to assess autophagic flux based on the cross correlation (CC) value. Our results demonstrate that FCCS can efficiently distinguish three autophagic structures, assess the induced autophagic flux, and discriminate different autophagy regulators. Compared with the commonly used fluorescence imaging technique, the resolution of FCCS remains unaffected by Brownian motion and fluorescent monomers in the cytoplasm and is well suitable to distinguishing differently colored autophagic structures and monitoring autophagy.

Mechanism of ameliorating cerebral ischemia/reperfusion injury by antioxidant inhibition of autophagy based on network pharmacology and experimental verification

Cerebral ischemia-reperfusion injury (CIRI) is one of the most difficult challenges in cerebrovascular disease research. It is primarily caused by excessive autophagy induced by oxidative stress. Previously, a novel compound X5 was found, and the excellent antioxidant activity of it was verified in this study. Moreover, network pharmacological analysis suggested that compound X5 was closely associated with autophagy and the mTOR pathway. In vitro, X5 could significantly inhibit the expression of autophagy proteins Beclin-1 and LC3-β, which are induced by H2O2, and promote the expression of SIRT1. In vivo, compound X5 significantly reduced the infarct size and improved the neurological function scores in the middle cerebral artery occlusion (MCAO) model of rats. In conclusion, ROS-induced autophagy is closely related to mTOR, SIRT1 and others, and X5 holds promise as a candidate for the treatment of CIRI.

Rhoa/ROCK, mTOR and Secretome-Based Treatments for Ischemic Stroke: New Perspectives

Ischemic stroke triggers a complex cascade of cellular and molecular events leading to neuronal damage and tissue injury. This review explores the potential therapeutic avenues targeting cellular signaling pathways implicated in stroke pathophysiology. Specifically, it focuses on the articles that highlight the roles of RhoA/ROCK and mTOR signaling pathways in ischemic brain injury and their therapeutic implications. The RhoA/ROCK pathway modulates various cellular processes, including cytoskeletal dynamics and inflammation, while mTOR signaling regulates cell growth, proliferation, and autophagy. Preclinical studies have demonstrated the neuroprotective effects of targeting these pathways in stroke models, offering insights into potential treatment strategies. However, challenges such as off-target effects and the need for tissue-specific targeting remain. Furthermore, emerging evidence suggests the therapeutic potential of MSC secretome in stroke treatment, highlighting the importance of exploring alternative approaches. Future research directions include elucidating the precise mechanisms of action, optimizing treatment protocols, and translating preclinical findings into clinical practice for improved stroke outcomes.

Crosstalk between autophagy and ferroptosis mediate injury in ischemic stroke by generating reactive oxygen species

Stroke represents a significant threat to global human health, characterized by high rates of morbidity, disability, and mortality. Predominantly, strokes are ischemic in nature. Ischemic stroke (IS) is influenced by various cell death pathways, notably autophagy and ferroptosis. Recent studies have increasingly highlighted the interplay between autophagy and ferroptosis, a process likely driven by the accumulation of reactive oxygen species (ROS). Post-IS, either the inhibition of autophagy or its excessive activation can escalate ROS levels. Concurrently, the interaction between ROS and lipids during ferroptosis further augments ROS accumulation. Elevated ROS levels can provoke endoplasmic reticulum stress-induced autophagy and, in conjunction with free iron (Fe2+), can trigger ferroptosis. Moreover, ROS contribute to protein and lipid oxidation, endothelial dysfunction, and an inflammatory response, all of which mediate secondary brain injury following IS. This review succinctly explores the mechanisms of ROS-mediated crosstalk between autophagy and ferroptosis and the detrimental impact of increased ROS on IS. It also offers novel perspectives for IS treatment strategies.

Autophagy-related 5 in acute ischemic stroke: Variation and linkage with neurofunction, and survival

OBJECTIVE

Autophagy-related 5 (ATG5) facilitates the pathologic process of acute ischemic stroke (AIS) via multiple ways. This study aimed to identify the association of serum ATG5 with clinical outcomes in AIS patients.

METHODS

Serum ATG5 from 280 AIS patients were detected at admission, Day (D)1, D3, D7, D30, and D90 after admission by enzyme-linked immunosorbent assay. The median (interquartile range) follow-up was 21.1 (5.9-43.9) months. Another 50 healthy controls (HCs) were also enrolled for serum ATG5 determination.

RESULTS

ATG5 was elevated (p < 0.001) (vs. HCs), and positively correlated with hyperlipidemia (p = 0.016), and the national institutes of health stroke scale score (p = 0.001) in AIS patients. Interestingly, ATG5 was increased from admission to D1, but gradually decreased until D90 (p < 0.001). Besides, 85 (30.4%) and 195 (69.6%) AIS patients were assessed as modified Rankin Scale (mRS) >2 and mRS ≤2 at D90, respectively. ATG5 at admission, D1, D3, D30, and D90 was elevated in AIS patients with mRS >2 versus those with mRS ≤2 (all p < 0.050). ATG5 at admission, D1, D3, D7, D30, or D90 was elevated in relapsed (vs. non-relapsed) or died (vs. survived) AIS patients (all p < 0.050). Recurrence-free survival was shortened in AIS patients with high (≥52.0 ng/mL) ATG5 versus those with low (<52.0 ng/mL) ATG5 at admission, D3, D7, and D30 (all p < 0.050); overall survival was shorter in AIS patients with high (vs. low) ATG5 at D7 and D30 (both p < 0.050).

INTERPRETATION

Serum ATG5 elevates at first, thereafter gradually declines, whose elevation associates with neurological dysfunction, recurrence, and death risk in AIS patients.

Intracerebroventricular BDNF infusion may reduce cerebral ischemia/reperfusion injury by promoting autophagy and suppressing apoptosis

Here, it was aimed to investigate the effects of intracerebroventricular (ICV) Brain Derived Neurotrophic Factor (BDNF) infusion for 7 days following cerebral ischemia (CI) on autophagy in neurons in the penumbra. Focal CI was created by the occlusion of the right middle cerebral artery. A total of 60 rats were used and divided into 4 groups as Control, Sham CI, CI and CI + BDNF. During the 7-day reperfusion period, aCSF (vehicle) was infused to Sham CI and CI groups, and BDNF infusion was administered to the CI + BDNF group via an osmotic minipump. By the end of the 7th day of reperfusion, Beclin-1, LC3, p62 and cleaved caspase-3 protein levels in the penumbra area were evaluated using Western blot and immunofluorescence. BDNF treatment for 7 days reduced the infarct area after CI, induced the autophagic proteins Beclin-1, LC3 and p62 and suppressed the apoptotic protein cleaved caspase-3. Furthermore, rotarod and adhesive removal test times of BDNF treatment started to improve from the 4th day, and the neurological deficit score from the 5th day. ICV BDNF treatment following CI reduced the infarct area by inducing autophagic proteins Beclin-1, LC3 and p62 and inhibiting the apoptotic caspase-3 protein while its beneficial effects were apparent in neurological tests from the 4th day.

Lonicerin promotes wound healing in diabetic rats by enhancing blood vessel regeneration through Sirt1-mediated autophagy

Among the numerous complications of diabetes mellitus, diabetic wounds seriously affect patients' quality of life and result in considerable psychological distress. Promoting blood vessel regeneration in wounds is a crucial step in wound healing. Lonicerin (LCR), a bioactive compound found in plants of the Lonicera japonica species and other honeysuckle plants, exhibits anti-inflammatory and antioxidant activities, and it recently has been found to alleviate ulcerative colitis by enhancing autophagy. In this study we investigated the efficacy of LCR in treatment of diabetic wounds and the underlying mechanisms. By comparing the single-cell transcriptomic data from healing and non-healing states in diabetic foot ulcers (DFU) of 5 patients, we found that autophagy and SIRT signaling activation played a crucial role in mitigating inflammation and oxidative stress, and promoting cell survival in wound healing processes. In TBHP-treated human umbilical vein endothelial cells (HUVECs), we showed that LCR alleviated cell apoptosis, and enhanced the cell viability, migration and angiogenesis. Furthermore, we demonstrated that LCR treatment dose-dependently promoted autophagy in TBHP-treated HUVECs by upregulating Sirt1 expression, and exerted its anti-apoptotic effect through the Sirt1-autophagy axis. Knockdown of Sirt1 significantly decreased the level of autophagy, and mitigated the anti-apoptotic effect of LCR. In a STZ-induced diabetic rat model, administration of LCR significantly promoted wound healing, which was significantly attenuated by Sirt1 knockdown. This study highlights the potential of LCR as a therapeutic agent for the treatment of diabetic wounds and provides insights into the molecular mechanisms underlying its effects.

Role of autophagy in ischemic stroke: insights from animal models and preliminary evidence in the human disease

Stroke represents a main cause of death and permanent disability worldwide. The molecular mechanisms underlying cerebral injury in response to the ischemic insults are not completely understood. In this article, we summarize recent evidence regarding the role of autophagy in the pathogenesis of ischemic stroke by reviewing data obtained in murine models of either transient or permanent middle cerebral artery occlusion, and in the stroke-prone spontaneously hypertensive rat. Few preliminary observational studies investigating the role of autophagy in subjects at high cerebrovascular risk and in cohorts of stroke patients were also reviewed. Autophagy plays a dual role in neuronal and vascular cells by exerting both protective and detrimental effects depending on its level, duration of stress and type of cells involved. Protective autophagy exerts adaptive mechanisms which reduce neuronal loss and promote survival. On the other hand, excessive activation of autophagy leads to neuronal cell death and increases brain injury. In conclusion, the evidence reviewed suggests that a proper manipulation of autophagy may represent an interesting strategy to either prevent or reduce brain ischemic injury.

Inhibition of OGFOD1 by FG4592 confers neuroprotection by activating unfolded protein response and autophagy after ischemic stroke

BACKGROUND

Acute ischemic stroke is a common neurological disease with a significant financial burden but lacks effective drugs. Hypoxia-inducible factor (HIF) and prolyl hydroxylases (PHDs) participate in the pathophysiological process of ischemia. However, whether FG4592, the first clinically approved PHDs inhibitor, can alleviate ischemic brain injury remains unclear.

METHODS

The infarct volumes and behaviour tests were first analyzed in mice after ischemic stroke with systemic administration of FG4592. The knockdown of HIF-1α and pretreatments of HIF-1/2α inhibitors were then used to verify whether the neuroprotection of FG4592 is HIF-dependent. The targets predicting and molecular docking methods were applied to find other targets of FG4592. Molecular, cell biological and gene knockdown methods were finally conducted to explore the potential neuroprotective mechanisms of FG4592.

RESULTS

We found that the systemic administration of FG4592 decreased infarct volume and improved neurological defects of mice after transient or permanent ischemia. Meanwhile, FG4592 also activated autophagy and inhibited apoptosis in peri-infarct tissue of mice brains. However, in vitro and in vivo results suggested that the neuroprotection of FG4592 was not classical HIF-dependent. 2-oxoglutarate and iron-dependent oxygenase domain-containing protein 1 (OGFOD1) was found to be a novel target of FG4592 and regulated the Pro-62 hydroxylation in the small ribosomal protein s23 (Rps23) with the help of target predicting and molecular docking methods. Subsequently, the knockdown of OGFOD1 protected the cell against ischemia/reperfusion injury and activated unfolded protein response (UPR) and autophagy. Moreover, FG4592 was also found to activate UPR and autophagic flux in HIF-1α independent manner. Blocking UPR attenuated the neuroprotection, pro-autophagy effect and anti-apoptosis ability of FG4592.

CONCLUSION

This study demonstrated that FG4592 could be a candidate drug for treating ischemic stroke. The neuroprotection of FG4592 might be mediated by inhibiting alternative target OGFOD1, which activated the UPR and autophagy and inhibited apoptosis after ischemic injury. The inhibition of OGFOD1 is a novel therapy for ischemic stroke.

CKLF induces microglial activation via triggering defective mitophagy and mitochondrial dysfunction

Although microglial activation is induced by an increase in chemokines, the role of mitophagy in this process remains unclear. This study aimed to elucidate the role of microglial mitophagy in CKLF/CKLF1 (chemokine-like factor 1)-induced microglial activation and neuroinflammation, as well as the underlying molecular mechanisms following CKLF treatment. This study determined that CKLF, an inducible chemokine in the brain, leads to an increase in mitophagy markers, such as DNM1L, PINK1 (PTEN induced putative kinase 1), PRKN, and OPTN, along with a simultaneous increase in autophagosome formation, as evidenced by elevated levels of BECN1 and MAP1LC3B (microtubule-associated protein 1 light chain 3 beta)-II. However, SQSTM1, a substrate of autophagy, was also accumulated by CKLF treatment, suggesting that mitophagy flux was reduced and mitophagosomes accumulated. These findings were confirmed by transmission electron microscopy and confocal microscopy. The defective mitophagy observed in our study was caused by impaired lysosomal function, including mitophagosome-lysosome fusion, lysosome generation, and acidification, resulting in the accumulation of damaged mitochondria in microglial cells. Further analysis revealed that pharmacological blocking or gene-silencing of mitophagy inhibited CKLF-mediated microglial activation, as evidenced by the expression of the microglial marker AIF1 (allograft inflammatory factor 1) and the mRNA of proinflammatory cytokines (Tnf and Il6). Ultimately, defective mitophagy induced by CKLF results in microglial activation, as observed in the brains of adult mice. In summary, CKLF induces defective mitophagy, microglial activation, and inflammation, providing a potential approach for treating neuroinflammatory diseases.Abbreviation: 3-MA: 3-methyladenine; AIF1: allograft inflammatory factor 1; ANOVA: analysis of variance; BAF: bafilomycin A1; BSA: bovine serum albumin; CCCP: carbonyl cyanide m-chlorophenyl hydrazone; cGAMP: cyclic GMP-AMP; CGAS: cyclic GMP-AMP synthase; CKLF/CKLF1: chemokine-like factor 1; CNS: central nervous system; DMEM: Dulbecco's Modified Eagle Medium; DNM1L: dynamin 1 like; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GFP: green fluorescence protein; IRF3: interferon regulatory factor 3; IgG: immunoglobulin G; LAMP1: lysosomal-associated membrane protein 1; LAPTM4A: lysosomal-associated protein transmembrane 4A; MAP1LC3B: microtubule-associated protein 1 light chain 3 beta; Mdivi-1: mitochondrial division inhibitor 1; mRFP: monomeric red fluorescent protein; mtDNA: mitochondrial DNA; MTORC1: mechanistic target of rapamycin kinase complex 1; OPTN: optineurin; PBS: phosphate-buffered saline; PCR: polymerase chain reaction; PINK1: PTEN induced putative kinase 1; PLL: poly-L-lysine; PRKN: parkin RBR E3 ubiquitin protein ligase; qPCR: quantitative polymerase chain reaction; ROS: reactive oxygen species; SQSTM1: sequestosome 1; TBK1: TANK-binding kinase 1; TFEB: transcription factor EB; VDAC: voltage-dependent anion channel.

Tetrahydropiperine, a natural alkaloid with neuroprotective effects in ischemic stroke

BACKGROUND

Ischemic stroke (IS) is a life-threatening neurological disease with various pathological mechanisms. Tetrahydropiperine (THP) is a natural alkaloid with protective effects against multiple diseases, such as seizure, and pain. This study was to examine the impact of THP on IS and investigate its potential mechanism.

MATERIAL AND METHODS

We employed network pharmacology and molecular docking techniques to identify the target proteins of THP for intervention in IS. Adult male Sprague-Dawley rats were used to create a permanent middle cerebral artery occlusion model. PC-12 cells were chosen to establish an oxygen-glucose deprivation (OGD) cell model. Disease modeling followed by nimodipine (NIMO); 3-methyladenine (3-MA) and rapamycin (RAP) interventions. Open field test, Longa score, balance beam test, and forelimb grip test were used to measure motor and neurological functions. The degree of neurological damage recovery was assessed through behavioral analysis, and cerebral infarction volume was determined using TTC staining. Morphological changes were examined through HE and Nissl staining, and ultrastructural changes in neurons were observed using transmission electron microscopy. The protein expression of autophagy and related pathways was analyzed through Western blot (WB). The appropriate hypoxia time and drug concentration were determined using CCK-8 assay, which also measured cell survival rate.

RESULTS

The network pharmacology findings indicated that the impact of THP on IS was enhanced in the PI3K/Akt signaling pathway. THP demonstrated robust docking capability with proteins associated with the autophagy and PI3K/Akt/mTOR, as indicated by the molecular docking outcomes. THP significantly improved behavioral damage, reduced the area of cerebral infarction, ameliorated histopathological damage from ischemia, increase neuronal survival, and alleviated ultrastructural damage in neurons (P < 0.05). THP enhanced the survival of PC-12 cells induced by OGD and ameliorated the morphological harm to the cells (P < 0.05). THP was found to elevate the quantities of P62, LC3-Ⅰ, PI3K, P-AKt/Akt, and P-mTOR/mTOR proteins while reducing the levels of Atg7 and Beclin1 proteins. The results of transmission electron microscopy showed no autophagosomes in the THP, 3-MA, and 3-MA + THP groups.

CONCLUSION

The activation of the PI3K/Akt/mTOR signaling pathway by THP inhibits autophagy and provides relief from neurological damage in IS.

Novel insight into the therapeutical potential of flavonoids from traditional Chinese medicine against cerebral ischemia/reperfusion injury

Cerebral ischemia/reperfusion injury (CIRI) is a major contributor to poor prognosis of ischemic stroke. Flavonoids are a broad family of plant polyphenols which are abundant in traditional Chinese medicine (TCM) and have beneficial effects on several diseases including ischemic stroke. Accumulating studies have indicated that flavonoids derived from herbal TCM are effective in alleviating CIRI after ischemic stroke in vitro or in vivo, and exhibit favourable therapeutical potential. Herein, we systematically review the classification, metabolic absorption, neuroprotective efficacy, and mechanisms of TCM flavonoids against CIRI. The literature suggest that flavonoids exert potential medicinal functions including suppressing excitotoxicity, Ca2+ overloading, oxidative stress, inflammation, thrombin's cellular toxicity, different types of programmed cell deaths, and protecting the blood-brain barrier, as well as promoting neurogenesis in the recovery stage following ischemic stroke. Furthermore, we identified certain matters that should be taken into account in future research, as well as proposed difficulties and opportunities in transforming TCM-derived flavonoids into medications or functional foods for the treatment or prevention of CIRI. Overall, in this review we aim to provide novel ideas for the identification of new prospective medication candidates for the therapeutic strategy against ischemic stroke.

The Activation of GABAAR Alleviated Cerebral Ischemic Injury via the Suppression of Oxidative Stress, Autophagy, and Apoptosis Pathways

Ischemic stroke is a devastating disease leading to neurologic impairment. Compounding the issue is the very limited array of available interventions. The activation of a γ-aminobutyric acid (GABA) type A receptor (GABAAR) has been reported to produce neuroprotective properties during cerebral ischemia, but its mechanism of action is not yet fully understood. Here, in a rat model of photochemically induced cerebral ischemia, we found that muscimol, a GABAAR agonist, modulated GABAergic signaling, ameliorated anxiety-like behaviors, and attenuated neuronal damage in rats suffering cerebral ischemia. Moreover, GABAAR activation improved brain antioxidant levels, reducing the accumulation of oxidative products, which was closely associated with the NO/NOS pathway. Notably, the inhibition of autophagy markedly relieved the neuronal insult caused by cerebral ischemia. We further established an oxygen-glucose deprivation (OGD)-induced PC12 cell injury model. Both in vivo and in vitro experiments demonstrated that GABAAR activation obviously suppressed autophagy by regulating the AMPK-mTOR pathway. Additionally, GABAAR activation inhibited apoptosis through inhibiting the Bax/Bcl-2 pathway. These data suggest that GABAAR activation exerts neuroprotective effects during cerebral ischemia through improving oxidative stress and inhibiting autophagy and apoptosis. Our findings indicate that GABAAR serves as a target for treating cerebral ischemia and highlight the GABAAR-mediated autophagy signaling pathway.

ATG5 Knockdown Attenuates Ischemia‒Reperfusion Injury by Reducing Excessive Autophagy-Induced Ferroptosis

Autophagy has been described to be both protective and pathogenic in cerebral ischemia/reperfusion (I/R) injury. The underlying association between autophagy and ferroptosis in ischemic stroke has not yet been clearly investigated. The purpose of this study was to explore the role of autophagy-related gene 5 (ATG5) in experimental ischemic stroke. After injection of ATG5 shRNA lentivirus, mice underwent surgery for transient middle cerebral artery occlusion (MCAO)-induced focal cerebral ischemia. The infarct volume, neurological function, apoptosis, reactive oxygen species (ROS), autophagy, and ferroptosis levels were evaluated. After MCAO, ATG5-knockdown mice had a smaller infarct size and fewer neurological deficits than wild-type mice. The levels of apoptosis and ROS in ischemic mouse brains were alleviated through ATG5 knockdown. The expression of LC3 I/II was reduced through ATG5 knockdown after MCAO. Additionally, the expression of beclin1 and LC3 II was increased after I/R, but the increase was counteracted by preconditioning with ATG5 knockdown. After ischemic stroke, the levels of Fe2+ and malondialdehyde (MDA) were increased, but they were reduced by ATG5 knockdown. Similarly, the expression of glutathione peroxidase 4 (GPX4) and glutathione (GSH) was decreased by I/R but elevated by ATG5 knockdown. The present study shows that ATG5 knockdown attenuates autophagy-induced ferroptosis, which may offer a novel potential approach for ischemic stroke treatment.

CB2 Cannabinoid Receptor as a Potential Target in Myocardial Infarction: Exploration of Molecular Pathogenesis and Therapeutic Strategies

The lipid endocannabinoid system has recently emerged as a novel therapeutic target for several inflammatory and tissue-damaging diseases, including those affecting the cardiovascular system. The primary targets of cannabinoids are cannabinoid type 1 (CB1) and 2 (CB2) receptors. The CB2 receptor is expressed in the cardiomyocytes. While the pathological changes in the myocardium upregulate the CB2 receptor, genetic deletion of the receptor aggravates the changes. The CB2 receptor plays a crucial role in attenuating the advancement of myocardial infarction (MI)-associated pathological changes in the myocardium. Activation of CB2 receptors exerts cardioprotection in MI via numerous molecular pathways. For instance, delta-9-tetrahydrocannabinol attenuated the progression of MI via modulation of the CB2 receptor-dependent anti-inflammatory mechanisms, including suppression of pro-inflammatory cytokines like IL-6, TNF-α, and IL-1β. Through similar mechanisms, natural and synthetic CB2 receptor ligands repair myocardial tissue damage. This review aims to offer an in-depth discussion on the ameliorative potential of CB2 receptors in myocardial injuries induced by a variety of pathogenic mechanisms. Further, the modulation of autophagy, TGF-β/Smad3 signaling, MPTP opening, and ROS production are discussed. The molecular correlation of CB2 receptors with cardiac injury markers, such as troponin I, LDH1, and CK-MB, is explored. Special attention has been paid to novel insights into the potential therapeutic implications of CB2 receptor activation in MI.

Cholinergic signaling of muscarinic receptors directly involves in the neuroprotection of muscone by inducing Ca2+ antagonism and maintaining mitochondrial function

ETHNOPHARMACOLOGICAL RELEVANCE

Musk, a traditional Chinese medicine, is broadly used in inducing resuscitation and refreshing the mind, activating blood and alleviating pain. It is commonly used for the treatment of ischemic stroke, and muscone is its core medicinal component.

AIM OF THE STUDY

The aim of this study was to explore whether muscone ameliorates neuronal damage through cholinergic signaling of muscarinic receptors.

MATERIALS AND METHODS

The effects of muscone were tested in a rat model of middle cerebral artery occlusion (MCAO) as well as injured neurons induced by oxygen-glucose deprivation (OGD) in PC12 cells. Cell counting kit 8 (CCK8) assay was used to measure the cell viability, and the production of lactate dehydrogenase (LDH) and adenosine-triphosphate (ATP) were examined by kit. 2',7'-Dichlorodihydrofluorescein diacetate (DCFH-DA), tetramethylrhodamine ethyl ester (TMRE) and Fluo-4 acetoxymethyl ester (Fluo-4 AM) staining were used to demonstrate effect of muscone on the reactive oxygen species (ROS) level, mitochondria membrane potential (MMP) and intracellular Ca2+ measurement in cells respectively, in which all of those staining was visualized by laser confocal microscope. For in vivo experiments, rats' cerebral blood flow was measured using laser Doppler blood flowmetry to evaluate the MCAO model, and a modified neurological severity score (mNSS) was used to assess the recovery of neurological function. Calculate infarct rate was measured by 2,3,5-Triphenyl Tetrazolium Chloride (TTC) staining. Except DCFH-DA and Fluo-4 AM staining, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl benzimidazolylcarbocyanine iodide (JC-1) staining was used to observe intracellular Ca2+ measurement in brain cells. Protein levels in cells and tissues were detected by Western blot.

RESULTS

Pretreatment with muscone significantly improved the cell viability, lactic acid production, mitochondrial membrane potential collapse and function, Ca2+ overload, ROS generation, and cell apoptosis in OGD PC12 cells. Muscone also regulated PI3K, ERK and AKT signal pathways by activating cholinergic signaling of muscarinic receptors in PC12 cells induced with OGD. More importantly, the blocking of cholinergic signaling of muscarinic receptors by atropine significantly reduces the neuroprotective effects of muscone, including the cell viability, Ca2+ efflux, and mitochondrial repair. Furthermore, muscone was found to effectively alleviate mitochondrial dysfunction and elevated levels of ROS induced by the MCAO in the brain tissue. Notably, this beneficial effect of muscone was attenuated by atropine but not by (+)-Sparteine.

CONCLUSIONS

Our study indicates that muscone exerts its neuroprotective effects by activating muscarinic receptors of cholinergic signaling, thus providing a promising therapeutic target for the treatment of OGD-induced nerve injury in stroke. The findings suggest that these treatments may hold potential benefits for stroke patients.

Transcription Factor EB: A Promising Therapeutic Target for Ischemic Stroke

Transcription factor EB (TFEB) is an important endogenous defensive protein that responds to ischemic stimuli. Acute ischemic stroke is a growing concern due to its high morbidity and mortality. Most survivors suffer from disabilities such as numbness or weakness in an arm or leg, facial droop, difficulty speaking or understanding speech, confusion, impaired balance or coordination, or loss of vision. Although TFEB plays a neuroprotective role, its potential effect on ischemic stroke remains unclear. This article describes the basic structure, regulation of transcriptional activity, and biological roles of TFEB relevant to ischemic stroke. Additionally, we explore the effects of TFEB on the various pathological processes underlying ischemic stroke and current therapeutic approaches. The information compiled here may inform clinical and basic studies on TFEB, which may be an effective therapeutic drug target for ischemic stroke.

Interplay of energy metabolism and autophagy

Macroautophagy/autophagy, is widely recognized for its crucial role in enabling cell survival and maintaining cellular energy homeostasis during starvation or energy stress. Its regulation is intricately linked to cellular energy status. In this review, covering yeast, mammals, and plants, we aim to provide a comprehensive overview of the understanding of the roles and mechanisms of carbon- or glucose-deprivation related autophagy, showing how cells effectively respond to such challenges for survival. Further investigation is needed to determine the specific degraded substrates by autophagy during glucose or energy deprivation and the diverse roles and mechanisms during varying durations of energy starvation.Abbreviations: ADP: adenosine diphosphate; AMP: adenosine monophosphate; AMPK: AMP-activated protein kinase; ATG: autophagy related; ATP: adenosine triphosphate; ER: endoplasmic reticulum; ESCRT: endosomal sorting complex required for transport; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GD: glucose deprivation; GFP: green fluorescent protein; GTPases: guanosine triphosphatases; HK2: hexokinase 2; K phaffii: Komagataella phaffii; LD: lipid droplet; MAP1LC3/LC3: microtubule-associated protein1 light chain 3; MAPK: mitogen-activated protein kinase; Mec1: mitosis entry checkpoint 1; MTOR: mechanistic target of rapamycin kinase; NAD (+): nicotinamide adenine dinucleotide; OGD: oxygen and glucose deprivation; PAS: phagophore assembly site; PCD: programmed cell death; PtdIns3K: class III phosphatidylinositol 3-kinase; PtdIns3P: phosphatidylinositol-3-phosphate; ROS: reactive oxygen species; S. cerevisiae: Saccharomyces cerevisiae; SIRT1: sirtuin 1; Snf1: sucrose non-fermenting 1; STK11/LKB1: serine/threonine kinase 11; TFEB: transcription factor EB; TORC1: target of rapamycin complex 1; ULK1: unc-51 like kinase 1; Vps27: vacuolar protein sorting 27; Vps4: vacuolar protein sorting 4.

Protective Effects of Liriodendrin on Myocardial Infarction-Induced Fibrosis in Rats via the PI3K/Akt Autophagy Pathway: A Network Pharmacology Study

BACKGROUND

Liriodendrin (LIR) has been reported to improve cardiac function in rats following myocardial infarction. However, its role and mechanism in reparative myocardial fibrosis remain unclear.

METHODS

In this study, a rat model of myocardial fibrosis was established via left anterior descending artery ligation and randomly divided into three groups (n = 6 per group): sham-operated, myocardial infarction, and LIR intervention (100 mg/kg/day) groups. The pharmacological effects of LIR were assessed using echocardiography, hematoxylin, and eosin (H&E) staining, and Masson staining. Network pharmacology and bioinformatics were utilized to identify potential mechanisms of LIR, which were further validated via western blot analysis.

RESULTS

Our findings demonstrated that LIR improved cardiac function, histology scores, and col lagen volume fraction. Moreover, LIR downregulated the expression of Beclin-1, LC3-II/LC3-I while upregulating the expression of p62, indicating LIR-inhibited autophagy in the heart after myocardial infarction. Further analysis revealed that the PI3K/Akt signaling pathway was significantly enriched and validated by western blot. This analysis suggested that the ratios of p- PI3K/PI3K, p-Akt/Akt, and p-mTOR/mTOR were significantly increased.

CONCLUSION

LIR may attenuate myocardial infarction-induced fibrosis in rats by inhibiting excessive myocardial autophagy, with the potential mechanism involving the activation of the PI3K/Akt/mTOR pathway.

Total Tau Protein Mediates the Association of Ischemic Cerebrovascular Disease with Cognitive Decline

Background

Patients with transient ischemic attack (TIA) or ischemic stroke demonstrate an increased risk of cognitive dysfunction. Accumulating evidence indicates that ischemic cerebrovascular disease (ICVD) may interact with the amyloid/tau/neurodegeneration (AT[N]) biomarkers to promote dementia. However, the precise pathological mechanisms remain to be fully characterized.

Objective

To elucidate the interrelationships among ICVD, ATN biomarkers in cerebrospinal fluid (CSF), and cognition.

Methods

A total of 2524 participants were recruited from the CABLE study. ICVD referred to TIA/ischemic stroke. Cognitive performance was assessed by China Modified Mini-Mental State Examination (CM-MMSE) and Montreal Cognitive Assessment-b (MoCA-b). Multivariate linear regression analyses were performed to evaluate the associations of ICVD with CSF ATN biomarkers and cognition. Causal mediation analyses were used to identify whether the association was mediated by ATN biomarkers.

Results

ICVD was associated with higher total-tau (t-tau) (p = 2.828×10-2) and poorer cognition (CM-MMSE: p = 1.539×10-5, MoCA-b: p = 4.552×10-6). Additionally, no discernible correlation surfaced between ICVD and amyloid-β (Aβ) 42 (p = 6.910×10-1) or phosphorylated tau (p-tau) (p = 4.324×10-1). The influence of ICVD on cognitive function was partially mediated by CSF t-tau (CM-MMSE: proportion: 2.74%, MoCA-b: proportion: 2.51%). Subgroup analyses revealed the influences of t-tau were especially evident in male (CM-MMSE: proportion: 5.45%, MoCA-b: proportion: 5.38%) and mid-life group (CM-MMSE: proportion: 9.83%, MoCA-b: proportion: 5.31%).

Conclusions

These results delineated t-tau as a potential mediator for the influence of ICVD on cognition. Targeting brain ischemia and alleviating neuronal injury induced by ischemia may be a promising approach for preventing cognitive decline.

Hypoxia and interleukin-1-primed mesenchymal stem/stromal cells as novel therapy for stroke

Promising preclinical stroke research has not yielded meaningful and significant success in clinical trials. This lack of success has prompted the need for refinement of preclinical studies with the intent to optimize the chances of clinical success. Regenerative medicine, especially using mesenchymal stem/stromal cells (MSCs), has gained popularity in the last decade for treating many disorders, including central nervous system (CNS), such as stroke. In addition to less stringent ethical constraints, the ample availability of MSCs also makes them an attractive alternative to totipotent and other pluripotent stem cells. The ability of MSCs to differentiate into neurons and other brain parenchymal and immune cells makes them a promising therapy for stroke. However, these cells also have some drawbacks that, if not addressed, will render MSCs unfit for treating ischaemic stroke. In this review, we highlighted the molecular and cellular changes that occur following an ischaemic stroke (IS) incidence and discussed the physiological properties of MSCs suitable for tackling these changes. We also went further to discuss the major drawbacks of utilizing MSCs in IS and how adequate priming using both hypoxia and interleukin-1 can optimize the beneficial properties of MSCs while eliminating these drawbacks.

Neuroprotective Effects and Therapeutic Potential of Dichloroacetate: Targeting Metabolic Disorders in Nervous System Diseases

Dichloroacetate (DCA) is an investigational drug used to treat lactic acidosis and malignant tumours. It works by inhibiting pyruvate dehydrogenase kinase and increasing the rate of glucose oxidation. Some studies have documented the neuroprotective benefits of DCA. By reviewing these studies, this paper shows that DCA has multiple pharmacological activities, including regulating metabolism, ameliorating oxidative stress, attenuating neuroinflammation, inhibiting apoptosis, decreasing autophagy, protecting the blood‒brain barrier, improving the function of endothelial progenitor cells, improving mitochondrial dynamics, and decreasing amyloid β-protein. In addition, DCA inhibits the enzyme that metabolizes it, which leads to peripheral neurotoxicity due to drug accumulation that may be solved by individualized drug delivery and nanovesicle delivery. In summary, in this review, we analyse the mechanisms of neuroprotection by DCA in different diseases and discuss the causes of and solutions to its adverse effects.

Seipin overexpression attenuates cerebral ischemia-reperfusion injury via preventing apoptosis and autophagy

BACKGROUND

Ischemic cerebrovascular disease (ICVD) is one of three fatal diseases in humans, along with heart disease and malignant tumors. Cerebral ischemia/reperfusion injury (CI/RI) is the primary cause of ICVD. Recently, seipin was reported to be crucial for lipid droplet formation, hepatic steatosis, and axonal atrophy. However, the function and mechanism of seipin in CI/RI has not been explicitly stated.

METHODS

Oxygen-glucose deprivation/reoxygenation (OGD/R) hippocampal neuron cell line (HT-22) and middle cerebral artery occlusion (MCAO) in rats were established. The levels of apoptosis- and autophagy-related proteins and seipin were confirmed by western blot. Cell proliferation was assessed with CCK-8, and ischemic infarction and pathological structure were monitored by TTC and H&E staining, and tissue apoptosis was assessed through TUNEL assay.

RESULTS

The proliferative activity was decreased, and apoptosis and autophagy pathways could also be induced in the OGD/R HT-22 cells. Seipin overexpression accelerated viability and inhibited apoptosis and autophagy in the OGD/R HT-22 cells. Moreover, the data revealed that seipin overexpression could also attenuate cerebral infarction, apoptosis. Autophagy pathways could be repressed by seipin in the MCAO rats.

CONCLUSION

Seipin has a protective role against CI/RI in rats, and its mechanism might be relevant to the suppression of apoptosis and autophagy, suggesting that seipin might be a latent target for CI/RI.

HYAL1 deficiency attenuates lipopolysaccharide-triggered renal injury and endothelial glycocalyx breakdown in septic AKI in mice

BACKGROUND

Renal dysfunction and disruption of renal endothelial glycocalyx are two important events during septic acute kidney injury (AKI). Here, the role and mechanism of hyaluronidase 1 (HYAL1) in regulating renal injury and renal endothelial glycocalyx breakdown in septic AKI were explored for the first time.

METHODS

BALB/c mice were injected with lipopolysaccharide (LPS, 10 mg/kg) to induce AKI. HYAL1 was blocked in vivo using lentivirus-mediated short hairpin RNA targeting HYAL1 (LV-sh-HYAL1). Biochemical assays were performed to measure the levels and concentrations of biochemical parameters associated with AKI as well as levels of inflammatory cytokines. Renal pathological lesions were determined by hematoxylin-eosin (HE) staining. Cell apoptosis in the kidney was detected using terminal-deoxynucleoitidyl transferase-mediated nick end labeling (TUNEL) assay. Immunofluorescence and immunohistochemical (IHC) staining assays were used to examine the levels of hyaluronic acid in the kidney. The protein levels of adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling, endothelial glycocalyx, and autophagy-associated indicators were assessed by western blotting.

RESULTS

The knockdown of HYAL1 in LPS-subjected mice by LV-sh-HYAL1 significantly reduced renal inflammation, oxidative stress, apoptosis and kidney dysfunction in AKI, as well as alleviated renal endothelial glycocalyx disruption by preventing the release of hyaluronic acid to the bloodstream. Additionally, autophagy-related protein analysis indicated that knockdown of HYAL1 significantly enhanced autophagy in LPS mice. Furthermore, the beneficial actions of HYAL1 blockade were closely associated with the AMPK/mTOR signaling.

CONCLUSION

HYAL1 deficiency attenuates LPS-triggered renal injury and endothelial glycocalyx breakdown in septic AKI in mice.

USP14 inhibition promotes recovery by protecting BBB integrity and attenuating neuroinflammation in MCAO mice

AIM

Blood-brain barrier (BBB) dysfunction is one of the hallmarks of ischemic stroke. USP14 has been reported to play a detrimental role in ischemic brain injury. However, the role of USP14 in BBB dysfunction after ischemic stroke is unclear.

METHODS

In this study, we tested the role of USP14 in disrupting BBB integrity after ischemic stroke. The USP14-specific inhibitor IU1 was injected into middle cerebral artery occlusion (MCAO) mice once a day. The Evans blue (EB) assay and IgG staining were used to assess BBB leakage 3 days after MCAO. FITC-detran test was slected to examine the BBB leakage in vitro. Behavior tests were conducted to evaluate recovery from ischemic stroke.

RESULTS

Middle cerebral artery occlusion increased endothelial cell USP14 expression in the brain. Furthermore, the EB assay and IgG staining showed that USP14 inhibition through IU1 injection protected against BBB leakage after MCAO. Analysis of protein expression revealed a reduction in the inflammatory response and chemokine release after IU1 treatment. In addition, IU1 treatment was found to rescue neuronal loss resulting from ischemic stroke. Behavior tests showed a positive effect of IU1 in attenuating brain injury and improving motor function recovery. In vitro study showed that IU1 treatment could alleviate endothelial cell leakage induced by OGD in cultured bend.3 cells through modulating ZO-1 expression.

CONCLUSIONS

Our results demonstrate a role for USP14 in disrupting the integrity of the BBB and promoting neuroinflammation after MCAO.

Syntaphilin Inactivation Can Enhance Axonal Mitochondrial Transport to Improve Spinal Cord Injury

Mitochondria are important organelle of eukaryotic cells. They consists of a large number of different proteins that provide most of the ATP and supply power for the growth, function, and regeneration of neurons. Therefore, smitochondrial transport ensures that adequate ATP is supplied for metabolic activities. Spinal cord injury (SCI), a detrimental condition, has high morbidity and mortality rates. Currently, the available treatments only provide symptomatic relief for long-term disabilities. Studies have implicated mitochondrial transport as a critical factor in axonal regeneration. Hence, enhancing mitochondrial transports could be beneficial for ameliorating SCI. Syntaphilin (Snph) is a mitochondrial docking protein that acts as a "static anchor," and its inhibition enhances mitochondrial transports. Therefore, Snph as a key mediator of mitochondrial transports, may contribute to improving axonal regeneration following SCI. Herein, we examine Snph's biological effects and its relation to mitochondrial pathway. Then, we elaborate on mitochondrial transports after SCI, the possible role of Snph in SCI, and some possible therapeutic approaches by Snph.