Cardamonin attenuates cerebral ischemia/reperfusion injury by activating the HIF-1α/VEGFA pathway

Sevoflurane alleviates intestinal ischemia-reperfusion injury in aged mice

Sevoflurane is a widely used inhalation anesthetic during the perioperative period. Recent studies have suggested that sevoflurane has an enteroprotective effect, but its mechanism is unclear. To explore the mechanism of sevoflurane in intestinal ischemia‒reperfusion injury, an intestinal ischemia‒reperfusion injury mouse model was established. First, intestinal ischemia‒reperfusion injury was compared between aged and young mice. The results showed that intestinal ischemia‒reperfusion injury caused pathological intestinal injury and disrupted the intestinal mucosal barrier. The aged mice had more severe intestinal ischemia‒reperfusion injury than the young mice and therefore had a lower survival rate. The aged mice subsequently received sevoflurane via inhalation. Sevoflurane alleviated the pathological injury to the intestinal mucosa and repaired the function of the intestinal mucosal barrier in aged mice, thus increasing the level of intestinal mucosal hypoxia-inducible factor-1α and improving the survival rate of aged mice. However, preoperative administration of the hypoxia-inducible factor-1α inhibitor BAY87-2243 could counteract the enteroprotective effect of sevoflurane and lower the expression level of heme oxygenase-1, a downstream antioxidant enzyme of hypoxia-inducible factor-1α. Our findings suggest that sevoflurane alleviates intestinal ischemia‒reperfusion injury in aged mice by repairing the intestinal mucosal barrier through the activation of hypoxia-inducible factor-1α/heme oxygenase-1, providing a new target for the treatment of intestinal ischemia‒reperfusion injury in aged mice.

Remote Ischemic Postconditioning Protects the Neurovascular Units in MCAO/R Rats through HIF-1α-Mediated Pathway

Remote ischemic postconditioning (RIPostC), administered after the onset of local ischemia, has been shown to have beneficial effects on neurological, vascular, and motor functions in animal models. However, the precise mechanisms and interactions underlying these functional improvements remain unclear. Our study aimed to determine whether RIPostC exerts protective effects on the neurovascular units (NVU) and to investigate whether this protection is mediated by hypoxia-inducible factor-1α (HIF-1α). We used left middle cerebral artery occlusion and reperfusion (MCAO/r) to induce ischemic stroke in rats and applied RIPostC. YC-1 was used to inhibit the activity of HIF-1α. Following the 12-day RIPostC treatment, MRI scans showed a significant reduction in infarct volume in the affected area, accompanied by an increase in HIF-1α protein levels and its downstream angiogenic factors in the ischemic zone. Additionally, RIPostC promoted angiogenesis in the ischemic penumbra, which, in turn, reduced neuronal loss and astrocyte activation. Behavioral assessments further indicated that RIPostC treatment partially restored the motor function in MCAO/r rats. However, the therapeutic effects of RIPostC were counteracted by the addition of YC-1, suggesting that the protective effects of RIPostC against NVU are mediated through HIF-1α. Overall, our research demonstrates that RIPostC is an effective rehabilitative intervention for protecting NVU in MCAO/r rats through the HIF-1α-mediated pathway.

The dynamic duo: Decoding the roles of hypoxia-inducible factors in neonatal hypoxic-ischemic brain injury

Neonatal hypoxic-ischemic encephalopathy (HIE) results in considerable mortality and neurodevelopmental disability, with a particularly high disease burden in low- and middle-income countries. Improved understanding of the pathophysiology underlying this injury could allow for improved diagnostic and therapeutic options. Specifically, hypoxia-inducible factors (HIF-1α and HIF-2α) likely play a key role, but that role is complex and remains understudied. This review analyses the recent findings seeking to uncover the impacts of HIF-1α and HIF-2α in neonatal hypoxic-ischemic brain injury (HIBI), focusing on their cell specific expression, time-dependant activities, and potential therapeutic implications. Recent findings have revealed temporal patterns of HIF-1α and HIF-2α expression following hypoxic-ischemic injury, with distinct functions for HIF-1α versus HIF-2α within the neonatal brain. Ongoing studies aimed at further revealing the relationship between HIF isoforms and developing targeted interventions offer promising avenues for therapeutic management which could improve long-term neurological outcomes in affected newborns.

Neuroprotective effects of arctigenin on cerebral ischemia-reperfusion injury in rats via the EPO/EPOR-JAK2-STAT5 signaling pathway

Introduction

Cerebral ischemia-reperfusion injury (CIRI) is a complex pathophysiological process with significant morbidity and mortality, and there is no specific agent. Previous studies have found that arctigenin can play an anti-CIRI role through anti-inflammatory and antioxidant effects. This study further explored the anti-CIRI mechanism of arctigenin via the EPO/EPOR-JAK2-STAT5 signaling pathway.

Methods

TTC and H&E staining were used to observe infarct volume and morphological changes in the brain, RT-PCR was used to detect EPO, EPOR, HIF, JAK2, STAT5, NF-κB mRNA expression, EPO/EPOR ratio was detected by immunofluorescence, and HIF was observed by immunohistochemical staining. The protein expression levels of JAK2 and STAT5 were detected, and the protein expression levels of EPO, EPOR, HIF, JAK2 and STAT5 were detected by western blot.

Results

Our results indicate that arctigenin significantly reduced infarct volume and improved histopathological changes in the brain tissues from CIRI rats at 24 h, 48 h, and 72 h after reperfusion by TTC and H&E staining. RT-PCR analysis showed that arctigenin could significantly upregulate the mRNA expressions of EPO, EPOR, and HIF and downregulate the mRNA expressions of JAK2, STAT5, and NF-κB in the brain tissues from CIRI rats at 24 h, 48 h, and 72 h after reperfusion. Immunofluorescence assay showed that the ratio of EPO/EPOR in CIRI rats at 24 h, 48 h, and 72 h post-reperfusion was significantly elevated by arctigenin. Arctigenin could upregulate the HIF protein expression while downregulate the protein expressions of JAK2, STAT5, and NFκB in the brain tissues from CIRI rats at 24 h, 48 h, and 72 h after reperfusion by immunohistochemical staining. The protein regulation results of EPO, EPOR, HIF, JAK2, and STAT5 were also confirmed by Western blot at 72 h after reperfusion, consistent with the above results.

Discussion

In conclusion, arctigenin demonstrated neuroprotective properties against CIRI potentially through the EPO/EPOR-JAK2-STAT5 signaling pathway. These findings provide a scientific rationale for further exploration of arctigenin as a therapeutic agent for stroke.

EFEMP1-Mediated Regulation of Choroidal Vascular Dysfunction in Myopia: Insights Into the FOXO3/VEGFA Pathway as a Therapeutic Target

Purpose

This study investigates the role of EFEMP1 in choroidal vascular dysfunction and its implications for myopia progression, specifically focusing on the FOXO3/VEGFA signaling pathway as a potential therapeutic target.

Methods

We utilized adeno-associated virus (AAV) to overexpress and knock down EFEMP1 in the choroid of guinea pigs. Subsequent proteomic analyses were conducted on the choroidal tissue. We used Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) to identify relevant pathways and genes. In vitro experiments were performed on RF/6A cells, where both EFEMP1 and FOXO3 underwent overexpression and knockdown. We conducted a series of cell culture experiments, including assessments of cell proliferation, migration, tube formation, and choroidal sprouting assays, to evaluate the functional effects of EFEMP1. Quantitative reverse transcription PCR and Western blot analyses were utilized to measure gene and protein expression levels.

Results

Silencing EFEMP1 significantly reduced choroidal vascular dysfunction and slowed the progression of myopia. Proteomic analysis demonstrated that EFEMP1 regulates FOXO3 activity, resulting in increased VEGFA expression in RF/6A cells and promoting angiogenesis. Conversely, knockdown of FOXO3 led to decreased VEGFA levels, confirming that EFEMP1 modulates VEGFA expression through FOXO3.

Conclusions

Targeting EFEMP1 may offer a novel therapeutic strategy for the prevention and treatment of myopia by alleviating associated vascular dysregulation. Further exploration of the FOXO3/VEGFA pathway could provide additional insights into therapeutic interventions for myopia.

Endothelial Cells and the Blood-Brain Barrier: Critical Determinants of Ineffective Reperfusion in Stroke

Ineffective reperfusion remains a critical challenge in neurointerventional treatment following ischemic stroke, with the integrity of the blood-brain barrier (BBB) being a key determinant of patient outcomes. This review explores the distinctive characteristics and roles of brain endothelial cells (ECs) in the context of stroke and ineffective reperfusion. We examine the unique properties of brain ECs compared to their counterparts in other tissues, focusing on their pathophysiological changes, functional impairments and the inflammatory cascades that follow stroke. Differences in gene expression between brain ECs and those in other organs offer deeper insights into their role in neuroprotective therapies. Additionally, drawing parallels between brain ECs and ECs from organs with similar ischemia-reperfusion injury profiles may inspire novel therapeutic approaches. This review highlights the critical importance of understanding the nuanced roles of ECs in BBB regulation, which ultimately impacts reperfusion outcomes.

Classical prescription Daqinjiao decoction inhibit cerebral ischemia/reperfusion induced necroptosis and ferroptosis through multiple mechanisms

ETHNOPHARMACOLOGICAL RELEVANCE

The Daqinjiao decoction (DQJT), a classical prescription, has been utilized for millennia in stroke management, yet its underlying mechanisms remained obscure.

AIM OF THE STUDY

The aim of this study was to elucidate the mechanisms through which DQJT mitigates cerebral ischemia/reperfusion injury (CI/RI).

MATERIALS AND METHODS

The quantification of DQJT's primary components were performed by HPLC. Pharmacological assessments were then conducted to ascertain DQJT's efficacy in a Middle Cerebral Artery Occlusion/Reperfusion (MCAO/R) model. Following this, untargeted metabolomics, lipidomics and network pharmacology analyses were undertaken to unveil potential mechanisms, which were subsequently validated. UPLC-Q-TOF/MS was utilized to detect DQJT-derived chemicals in brain tissue, and molecular docking techniques were employed to investigate the bioactive compounds.

RESULTS

DQJT treatment reduced brain damage induced by MCAO/R, as evidenced by decreased infarct sizes, enhanced behavioral function scores, and diminished neuronal damages. Untargeted metabolomics and lipidomics revealed that DQJT improved metabolism of unsaturated fatty acids. According to network pharmacology, lipid metabolism, cAMP signaling pathway and toll-like receptor signaling pathway pathways were notably affected, with HSP90AA1, TLR4, and PKA identified as potential targets of DQJT. Immunofluorescence and Western blot analyses further demonstrated that DQJT counteracted necroptosis and ferroptosis by inhibiting the HSP90AA1 and TLR4 pathways and enhancing the PKA pathway. Molecular docking results supported that the possible pharmacodynamic substances of DQJT in protecting against CI/RI.

CONCLUSION

This research established that DQJT attenuates brain injury induced by MCAO/R through the modulation of necroptosis and ferroptosis via pathways including HSP90AA1, TLR4, and PKA. It shed light on the potential mechanisms and effective constituents of DQJT in stroke treatment, paving the way for further exploration of this ancient formula.

Melastoma dodecandrum lour. Protects against cerebral ischemia-reperfusion injury by ameliorating oxidative stress and endoplasmic reticulum stress

ETHNOPHARMACOLOGICAL RELEVANCE

Melastoma dodecandrum Lour. (MD), a traditional Chinese medicine used by the She ethnic group, has been used to treat cerebral ischemia-reperfusion (CIR) injury due to its efficacy in promoting blood circulation and removing blood stasiss; however, the therapeutic effects and mechanisms of MD in treating CIR injury remain unclear.

AIM

To investigate the protective effects of MD on CIR injury, in addition to its impact on oxidative stress, endoplasmic reticulum (ER) stress, and cell apoptosis.

MATERIALS AND METHODS

The research was conducted using both cell experiments and animal experiments. The CCK-8 method, immunofluorescence staining, and flow cytometry were used to analyze the effects of MD-containing serum on oxygen-glucose deprivation/reperfusion (OGD/R)-induced PC12 cell viability, reactive oxygen species (ROS) clearance, anti-inflammatory, neuroprotection and inhibition of apoptosis. Furthermore, 2,3,5-Triphenyl tetrazolium chloride staining, hematoxylin and eosin staining, Nissl staining, and immunohistochemistry were used to detect infarct size, pathological changes, Nissl corpuscula and neuronal protein expression in middle cerebral artery occlusion (MCAO) rats. Polymerase chain reaction and Western Blotting were conducted in cell and animal experiments to detect the expression levels of ER stress-related genes and proteins.

RESULTS

The MD extract enhanced the viability of PC12 cells under OGD/R modeling, reduced ROS and IL-6 levels, increased MBP levels, and inhibited cell apoptosis. Furthermore, MD improved the infarct area in MCAO rats, increased the number of Nissl bodies, and regulated neuronal protein levels including Microtubule-Associated Protein 2 (MAP-2), Myelin Basic Protein (MBP), Glial Fibrillary Acidic Protein (GFAP), and Neurofilament 200 (NF200). Additionally, MD could regulate the expression levels of oxidative stress proteins malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase (SOD), and catalase (CAT). Both cell and animal experiments demonstrated that MD could inhibit ER stress-related proteins (GRP78, ATF4, ATF6, CHOP) and reduce cell apoptosis.

CONCLUSION

This study confirmed that the therapeutic mechanism of the MD extract on CIR injury was via the inhibition of oxidative stress and the ER stress pathway, in addition to the inhibition of apoptosis.

Sphk1/S1P pathway promotes blood-brain barrier breakdown after intracerebral hemorrhage through inducing Nlrp3-mediated endothelial cell pyroptosis

Intracerebral hemorrhage (ICH) is a severe stroke subtype with high mortality and limited therapeutic options. The blood-brain barrier (BBB) breakdown post-ICH exacerbates secondary brain injury, highlighting the need for targeted therapies to preserve the BBB integrity. We aim to investigate the role of the Sphk1/S1P pathway in BBB breakdown following ICH and to evaluate the therapeutic potential of Sphk1 inhibition in mitigating this breakdown. Using a combination of human patient samples, mouse models of ICH, and in vitro cellular assays, we assessed the expression levels of Sphk1/S1P after ICH and changes of the BBB after ICH. The Sphk1 inhibitor PF543 and siRNAs were utilized to explore the pathway's impact on BBB integrity and the underlying mechanisms. The results indicate significant upregulation of Sphk1/S1P in the peri-hematomal brain tissue after ICH, which correlates with increased BBB leakage. Pharmacological inhibition of Sphk1 with PF543 attenuates BBB leakage, reduces hematoma volume, and improves neurological outcomes in mice. At the molecular and ultrastructural level, Sphk1 inhibition protects the BBB integrity by preserving tight junction proteins and suppressing endothelial transcytosis. Furthermore, mechanistic studies reveal that Sphk1 promotes Nlrp3-mediated pyroptosis of brain endothelial cells through the ERK1/2 signaling pathway. Taken together, the Sphk1/S1P pathway plays a critical role in ICH-induced BBB breakdown, and its inhibition represents a promising therapeutic strategy for ICH management.

Targeting Neuroinflammation and Apoptosis: Cardamonin's Cognitive Benefits in Alzheimer's 5XFAD Mice

This study aimed to evaluate the cognitive-enhancing and neuroprotective effects of cardamonin in the 5XFAD transgenic mouse model of Alzheimer's disease (AD). We treated six-month-old female 5XFAD mice with cardamonin at 5 mg/kg, 10 mg/kg, and 20 mg/kg. Cognitive function was assessed using the Morris Water Maze (MWM) and Novel Object Recognition (NOR) tests. ELISA, western blot, and PCR analyses evaluated amyloid-beta (Aβ) levels, neuroinflammation markers, and apoptosis-related factor expression. All animals survived without toxicity. Cardamonin treatment significantly improved spatial learning and memory retention in MWM and NOR tests, with the 20 mg/kg dose showing the most pronounced effects. Additionally, cardamonin reduced soluble and insoluble Aβ levels in the frontal cortex and hippocampus. The treatment also significantly decreased neuroinflammatory markers, with IL-1β, IL-6, and TNF-α levels dropping substantially at higher doses. Cardamom treatment also normalizes cleaved caspase 3, GFAP, Iba-1, PSD-95, and synaptophysin, which aids in restoring synaptic integrity. Furthermore, cardamonin led to a marked reduction in apoptosis-related gene expression, indicating its potential to mitigate neurodegeneration. Cardamonin demonstrates significant cognitive-enhancing and neuroprotective properties in the 5XFAD mouse model, suggesting its potential as a therapeutic agent for AD. These findings support further investigation into cardamonin's mechanisms and applicability in treating neurodegenerative disorders.

Catalpol regulates apoptosis and proliferation of endothelial cell via activating HIF-1α/VEGF signaling pathway

Burn injuries, especially severe ones, causes microcirculation disorders in local wounds and distant tissues, leading to ischemia and hypoxia of body tissues and organs. The key to prevent and treat complications and improve prognosis after burns is to improve the state of ischemia and hypoxia of tissue and restore the blood supply of organs. Catalpol is an iridoid glycoside compound isolated from Rehmannia radix, which has been widely reported to have various of functions, including antioxidative stress, anti-inflammation, anti-apoptosis, and neuroprotection. However, the pharmacologic action and underlying mechanism of Catalpol in angiogenesis after burn injury remains unclear. The study investigated whether Catalpol regulates apoptosis and proliferation following vascular injury induced by burns using an in vitro model of oxygen-glucose deprivation (OGD) with a human umbilical vein endothelial (HUVE) cell line. The results showed that treatment with Catalpol reduces the level of apoptosis and promotes proliferation of endothelial cell. Mechanistically, Catalpol increases the expression of vascular endothelial growth factor (VEGF) by activating Hypoxia-inducible factor-1α (Hif-1α), resulting in increased expression of related downstream effector molecules. The current study suggested that Catalpol is a promising compound for endothelial protection in burns. It may be an efficient Hif-1α activator for endothelial cell deprived of oxygen and glucose.

Cardamonin Attenuates Myocardial Ischemia/Reperfusion-Induced Ferroptosis Through Promoting STAT3 Signaling

Objective

Ferroptosis is intricately associated with the pathophysiology processes of myocardial ischemia. Cardamonin (CAR) has been shown to provide significant protection against tissue damage due to multiple ischemia/reperfusion. This study aimed to examine the cardioprotective properties of CAR in myocardial ischemia/reperfusion injury (MIRI) and provide insights into the possible mechanisms involved.

Methods

An MIRI mice model was conducted by coronary artery ligation, and the effects of CAR on myocardial tissue damage were evaluated by infarct size assessment, echocardiography, and H&E staining. The extent of ferroptosis was detected by examining the levels of ferroptosis-related proteins and lipid reactive oxygen species (ROS). The function pathway of CAR was analyzed by network pharmacology and verified using Western blotting. In addition, we induced hypoxia/reoxygenation (H/R) in cardiomyocytes to detect SLC7A11 expression, ROS level, mitochondrial iron content, and oxidative stress marker levels. The target protein of CAR was identified by Western blotting and molecular docking. We then evaluated the regulatory role of STAT3 on MIRI-induced ferroptosis by silencing STAT3.

Results

In our study, CAR demonstrated a reduction in myocardial histopathological damage and mitigation of ferroptosis in MIRI mice. Through network pharmacology analysis and Western blotting, our findings indicated that CAR modulates the AGE-RAGE signaling pathway, particularly impacting STAT3. Meanwhile, in vitro experiments revealed that advanced-glycation end products (AGEs) exacerbated H/R-induced ferroptosis, whereas CAR alleviated this ferroptosis in the presence of both AGEs and H/R. CAR was observed to enhance STAT3 expression in H/R+AGRs-treated cardiomyocytes. Molecular docking results demonstrated favorable binding interactions between CAR and STAT3. Our study confirmed that CAR mitigated MIRI-induced myocardial injury and ferroptosis through targeting STAT3 in mice.

Conclusion

In conclusion, CAR inhibited ferroptosis by activating the STAT3 signaling, thereby mitigating MIRI.

Identification of active ingredients in Naomaitai capsules using high-resolution mass spectrometry unite molecular network analysis and prediction of their action mechanisms

RATIONALE

Although Naomaitai capsule (NMC) is widely used in clinical practice and has a good curative effect for cerebral infarction, its material basis and mechanism of action remain unclear.

METHODS

In this study, ultra-high-performance liquid chromatography (UHPLC) coupled with quadrupole Orbitrap MS technology was used to analyse the in vivo and in vitro components of NMC, and the Global Natural Products Social Molecular Networking website was used to further analyse the components of NMC. Next, systems biology approaches were employed to investigate the mechanism of action of NMC. Finally, molecular docking technology was used to verify the network pharmacological results.

RESULTS

In total, 177 compounds were identified in vitro, including 65 terpenoids, 62 flavonoids, 25 organic acids and 11 quinones. 64 compounds were identified in the blood of mice, and the main active components included ginkgolide C, ginkgolide A, ligustilide, tanshinone IIB, olmelin, emodin and puerarin. The main targets in vivo included TP53, SRC, STAT3, PIK3CA and PIK3R1.

CONCLUSIONS

In conclusion, this study has revealed that NMC acts on multiple targets in the body through various active components, exerting synergistic effects in the treatment of CI. Its mechanism of action may involve inhibiting neuronal apoptosis, oxidative stress and inflammatory responses as well as reducing cerebral vascular permeability and promoting cerebral vascular regeneration.

Metabolomics and quantitative analysis to determine differences in the geographical origins and species of Chinese dragon's blood

Objective

The aim of this study was to comprehensively analyze the differences in Chinese dragon's blood (CDB), specifically Dracaena cochinchinensis and Dracaena cambodiana, from different geographical origins.

Methods

Metabolomic analysis of CDB was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A reliable ultrahigh-performance liquid chromatography method with a photodiode array detector (UHPLC-PDA) was developed and applied for the quantitative analysis of 12 phenolic compounds in 51 batches of samples.

Results

A total of 1394 metabolites were detected, of which 467 were identified as differentially accumulated metabolites. Multivariate analysis revealed that both origin and species had an effect on the composition of CDB, with greater variation between species. 19 phenolic compounds were selected as quality markers to distinguish D. cochinchinensis (Hdsp) from D. cambodiana (Hdca), and oppositin and spinoflavanone a were identified as quality markers to discriminate D. cochinchinensis samples from Hainan (Hdsp) and Guangxi Provinces (Gdc). Quantitative analysis indicated that four phenolic compounds, including loureirin D, 4H-1-benzopyran-4-one,2,3-dihydro-3,5,7-trihydroxy-3-[(4-methoxyphenyl)methyl]-,(R)-, loureirin B, and pterostilbene, showed significant differences between Gdc and Hdsp. Additionally, five phenolic compounds, namely resveratrol, loureirin D, pinostilbene, 4H-1-benzopyran-4-one,2,3-dihydro-3,5,7-trihydroxy-3-[(4-methoxyphenyl)methyl]-, (R)-, and loureirin B, exhibited significant differences between Hdsp and Hdca.

Conclusion

There are significant differences in the quality of CDB from different geographical origins and species, which lays the foundation for the in-depth development and utilization of different sources of CDB.

HIF-1α knockdown attenuates inflammation and oxidative stress in ischemic stroke male rats via CXCR4/NF-κB pathway

BACKGROUND

Hypoxia inducible factor-1α (HIF-1α) is a sensitive indicator of oxygen homeostasis, of which the expression elevates following hypoxia/ischemia. This study reveals the specific mechanisms underlying the effects of HIF-1α on ischemic stroke (IS).

METHODS

IS model was established using middle cerebral artery occlusion (MCAO)-modeled male rats and oxygen glucose deprivation/reoxygenation (OGD/R)-treated mice hippocampal cells HT22, followed by the silencing of HIF-1α and the overexpression of C-X-C motif chemokine receptor 4 (CXCR4) and nuclear factor-kappa B (NF-κB). Following the surgery, Garcia's grading scale was applied for neurological evaluation. Cerebral infarcts and injuries were visualized using 2,3,5-triphenyltetrazolium chloride and hematoxylin-eosin staining. The levels of tumor necrosis factor-α, Interleukin (IL)-6, IL-1β, malondialdehyde, and 8-hydroxy-2'-deoxyguanosine, were calculated via ELISA. MTT assay and lactate dehydrogenase (LDH) assay kit were adopted to determine the viability and cytotoxicity of OGD/R-modeled cells. Reactive oxygen species (ROS) generation was evaluated using a 2'-7'dichlorofluorescin diacetate (DCFH-DA) probe. The levels of HIF-1α, CXCR4, and NF-κB p65 were quantified via Western blot and immunofluorescence, respectively.

RESULTS

HIF-1α knockdown improved Garcia's score, attenuated the cerebral infarct, inflammation, and ROS generation, and alleviated the levels of inflammatory cytokines and CXCR4/NF-κB p65 in MCAO-modeled rats. Such effects were reversed following the overexpression of CXCR4 and NF-κB. Also, in OGD/R-treated HT22 cells, HIF-1α silencing diminished the cytotoxicity and ROS production and reduced the expressions of CXCR4/NF-κB p65, while promoting viability. However, CXCR4/NF-κB p65 overexpression did the opposite.

CONCLUSION

HIF-1α knockdown alleviates inflammation and oxidative stress in IS through the CXCR4/NF-κB pathway.

The Role of Antioxidants in the Therapy of Cardiovascular Diseases-A Literature Review

Antioxidants are endogenous and exogenous substances with the ability to inhibit oxidation processes by interacting with reactive oxygen species (ROS). ROS, in turn, are small, highly reactive substances capable of oxidizing a wide range of molecules in the human body, including nucleic acids, proteins, lipids, carbohydrates, and even small inorganic compounds. The overproduction of ROS leads to oxidative stress, which constitutes a significant factor contributing to the development of disease, not only markedly diminishing the quality of life but also representing the most common cause of death in developed countries, namely, cardiovascular disease (CVD). The aim of this review is to demonstrate the effect of selected antioxidants, such as coenzyme Q10 (CoQ10), flavonoids, carotenoids, and resveratrol, as well as to introduce new antioxidant therapies utilizing miRNA and nanoparticles, in reducing the incidence and progression of CVD. In addition, new antioxidant therapies in the context of the aforementioned diseases will be considered. This review emphasizes the pleiotropic effects and benefits stemming from the presence of the mentioned substances in the organism, leading to an overall reduction in cardiovascular risk, including coronary heart disease, dyslipidaemia, hypertension, atherosclerosis, and myocardial hypertrophy.

The relationship between hypoxia and Alzheimer's disease: an updated review

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases, and the most prevalent form of dementia. The main hallmarks for the diagnosis of AD are extracellular amyloid-beta (Aβ) plaque deposition and intracellular accumulation of highly hyperphosphorylated Tau protein as neurofibrillary tangles. The brain consumes more oxygen than any other organs, so it is more easily to be affected by hypoxia. Hypoxia has long been recognized as one of the possible causes of AD and other neurodegenerative diseases, but the exact mechanism has not been clarified. In this review, we will elucidate the connection between hypoxia-inducible factors-1α and AD, including its contribution to AD and its possible protective effects. Additionally, we will discuss the relationship between oxidative stress and AD as evidence show that oxidative stress acts on AD-related pathogenic factors such as mitochondrial dysfunction, Aβ deposition, inflammation, etc. Currently, there is no cure for AD. Given the close association between hypoxia, oxidative stress, and AD, along with current research on the protective effects of antioxidants against AD, we speculate that antioxidants could be a potential therapeutic approach for AD and worth further study.

Upregulation of circ-IGF1R increased therapeutic effect of hypoxia-pretreated ADSC-derived extracellular vesicle by regulating miR-503-5p/HK2/VEGFA axis

Diabetes mellitus is a major cause of blindness and chronic ulcers in the working-age population worldwide. Wound healing is deeply dependent on neovascularization to restore blood flow. Former research has found that differentially expressed circular RNAs (circRNAs) are associated with hyperglycaemia-induced endothelial cell damage, and hypoxia-pretreated adipose-derived stem cells (ADSCs)-extracellular vesicle (HEV) transplants have a more therapeutic effect to enhance wound healing in diabetic mice by delivery circRNA. The current investigation employed high-throughput sequencing to identify circRNAs that are abnormally expressed between EV and HEV. The regulatory mechanism and predicted targets of one differentially expressed circRNA, circ-IGF1R, were investigated utilizing bioinformatics analyses, luciferase reporter assays, angiogenic differentiation assays, flow cytometric apoptosis analysis and RT-qPCR. Circ-IGF1R expression increased in HEV, and downregulation of circ-IGF1R suppressed and reversed the promotion effect of HEV on angiogenesis in ulcerated tissue. Bioinformatics analyses and luciferase reporter assays confirmed that miR-503-5p was the downstream target of circ-IGF1R, and inhibiting miR-503-5p restored the promotion effect of HEV on angiogenesis after circ-IGF1R silence. The study also found that miR-503-5p can interact with 3'-UTR of both HK2 and VEGFA. Overexpression of HK2 or VEGFA restored the promotion effect of HExo on angiogenesis after circ-IGF1R silence. Overexpression miR-503-5p or silence HK2/VEGFA reversed the protective effect of circ-IGF1R to MLMECs angiogenic differentiation. Overexpression of circ-IGF1R increased the protective effect of HEV on the promotion of wound healing in mice with diabetes. Circ-IGF1R promotes HIF-1α expression through miR-503-5p sponging. Our data demonstrate that circ-IGF1R overexpression EVs from ADSCs suppress high glucose-induced endothelial cell damage by regulating miR-503-5p/HK2/VEGFA axis.

β-asarone induces viability and angiogenesis and suppresses apoptosis of human vascular endothelial cells after ischemic stroke by upregulating vascular endothelial growth factor A

Ischemic stroke (IS) is a disease with a high mortality and disability rate worldwide, and its incidence is increasing per year. Angiogenesis after IS improves blood supply to ischemic areas, accelerating neurological recovery. β-asarone has been reported to exhibit a significant protective effect against hypoxia injury. The ability of β-asarone to improve IS injury by inducing angiogenesis has not been distinctly clarified. The experimental rats were induced with middle cerebral artery occlusion (MCAO), and oxygen-glucose deprivation (OGD) model cells were constructed using human microvascular endothelial cell line (HMEC-1) cells. Cerebral infarction and pathological damage were first determined via triphenyl tetrazolium chloride (TTC) and hematoxylin and eosin (H&E) staining. Then, cell viability, apoptosis, and angiogenesis were assessed by utilizing cell counting kit-8 (CCK-8), flow cytometry, spheroid-based angiogenesis, and tube formation assays in OGD HMEC-1 cells. Besides, angiogenesis and other related proteins were identified with western blot. The study confirms that β-asarone, like nimodipine, can ameliorate cerebral infarction and pathological damage. β-asarone can also upregulate vascular endothelial growth factor A (VEGFA) and endothelial nitric oxide synthase (eNOS) and induce phosphorylation of p38. Besides, the study proves that β-asarone can protect against IS injury by increasing the expression of VEGFA. In vitro experiments affirmed that β-asarone can induce viability and suppress apoptosis in OGD-mediated HMEC-1 cells and promote angiogenesis of OGD HMEC-1 cells by upregulating VEGFA. This establishes the potential for β-asarone to be a latent drug for IS therapy.

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.

Chrysin inhibits ferroptosis of cerebral ischemia/reperfusion injury via regulating HIF-1α/CP loop

Chrysin is a natural flavonoid with powerful neuroprotective capacity. Cerebral ischemia/reperfusion injury (CIRI) is associated with oxidative stress and ferroptosis. Hypoxia-inducible factor 1α (HIF-1α) and ceruloplasmin (CP) are the critical targets for oxidation reactions and iron transport. But the regulatory mechanism between them is still unclear. Transient middle cerebral artery occlusion (tMCAO) model in rats and oxygen and glucose deprivation/re-oxygenation (OGD/R) model in PC12 cells were applied. Pathological tissue staining and biochemical kit were used to evaluate the effect of chrysin. The relationship between HIF-1α and CP was verified by transcriptomics, qRT-PCR and Western blot. In CIRI, HIF-1α/CP loop was discovered to be the regulatory pathway of ferroptosis. CIRI led to activation and nuclear translocation of HIF-1α, which promoted CP transcription and translation, and downstream ferroptosis. Inhibition of HIF-1α had opposite effect on CP and ferroptosis regulation. Overexpression of CP increased the expression of HIF-1α, nevertheless, inhibited the nuclear translocation of HIF-1α and alleviated CIRI. Silencing CP promoted HIF-1α elevation in nucleus and aggravated CIRI. Mechanistically, chrysin restrained HIF-1α nuclear translocation, thereby inhibiting CP transcription and translation, which in turn reduced downstream HIF-1α expression and mitigated ferroptosis in CIRI. Our results highlight chrysin restrains ferroptosis in CIRI through HIF-1α/CP loop.

Sustained release of vascular endothelial growth factor A and basic fibroblast growth factor from nanofiber membranes reduces oxygen/glucose deprivation-induced injury to neurovascular units

Upregulation of vascular endothelial growth factor A/basic fibroblast growth factor (VEGFA/bFGF) expression in the penumbra of cerebral ischemia can increase vascular volume, reduce lesion volume, and enhance neural cell proliferation and differentiation, thereby exerting neuroprotective effects. However, the beneficial effects of endogenous VEGFA/bFGF are limited as their expression is only transiently increased. In this study, we generated multilayered nanofiber membranes loaded with VEGFA/bFGF using layer-by-layer self-assembly and electrospinning techniques. We found that a membrane containing 10 layers had an ideal ultrastructure and could efficiently and stably release growth factors for more than 1 month. This 10-layered nanofiber membrane promoted brain microvascular endothelial cell tube formation and proliferation, inhibited neuronal apoptosis, upregulated the expression of tight junction proteins, and improved the viability of various cellular components of neurovascular units under conditions of oxygen/glucose deprivation. Furthermore, this nanofiber membrane decreased the expression of Janus kinase-2/signal transducer and activator of transcription-3 (JAK2/STAT3), Bax/Bcl-2, and cleaved caspase-3. Therefore, this nanofiber membrane exhibits a neuroprotective effect on oxygen/glucose-deprived neurovascular units by inhibiting the JAK2/STAT3 pathway.

Heat-shock protein A12A attenuates oxygen-glucose deprivation/reoxygenation-induced human brain microvascular endothelial cell dysfunction via PGC-1α/SIRT3 pathway

Ischemic stroke is a life-threatening brain disease with the leading cause of disability and mortality worldwide. Heat-shock protein A12A (HSPA12A) is recognized as a neuroprotective target for treating ischemic stroke; however, its regulatory mechanism has been not fully elucidated yet. Human brain microvascular endothelial cells (hBMECs) were induced by oxygen-glucose deprivation/reoxygenation (OGD/R) to mimic ischemic stroke. Gain- and loss-of-function experiments were conducted to explore the regulation of HSAPA12 and PGC-1α. Cell viability, apoptosis, and permeability were assessed by CCK-8, TUNEL, and transendothelial electrical resistance (TEER) assays, respectively. The expression of HSPA12A and corresponding proteins was measured by western blot. Cell immunofluorescence was adopted to evaluate ZO-1 expression. THP-1 cells were applied to adhere hBMECs in vitro to simulate leukocyte adhesion in the brain. HSPA12A was downregulated in OGD/R-treated hBMECs. HSPA12A overexpression significantly suppressed OGD/R-induced cell viability loss and apoptosis in hBMECs. Meanwhile, HSPA12A overexpression attenuated blood-brain barrier (BBB) integrity in OGD/R-induced hBMECs, evidenced by the restored TEER value and the upregulated ZO-1, occludin, and claudin-5. HSPA12A also restricted OGD/R-induced attachment of THP-1 cells to hBMECs, accompanied with downregulating ICAM-1 and VCAM-1. Additionally, OGD/R-caused downregulation of PGC-1α/SIRT3 in hBMECs was partly restored by HSPA12A overexpression. Furthermore, the above effects of HSPA12A on OGD/R-induced hBMECs injury were partly reversed by PGC-1α knockdown. HSPA12A plays a protective role against OGD/R-induced hBMECs injury by upregulating PGC-1α, providing a potential neuroprotective role of HSPA12A in ischemic stroke.

The neuroprotective mechanisms of naringenin: Inhibition of apoptosis through the PI3K/AKT pathway after hypoxic-ischemic brain damage

ETHNOPHARMACOLOGICAL RELEVANCE

Naringenin (NGN) is a widely distributed flavonoid with potent antioxidant and neuroprotective properties. Neuroprotective agents play a crucial role in the treatment of hypoxic-ischemic encephalopathy (HIE). It has shown potential therapeutic effects for neurological disorders. However, its efficacy on HIE is yet to be investigated.

AIM OF THE STUDY

This study aims to investigate the potential neuroprotective effect of naringenin and its underlying molecular mechanisms in reducing oxidative stress, apoptosis, and improving brain outcomes following HIE. Additionally, the study aims to identify the potential targets, mechanisms, and functions of naringenin using network pharmacology analysis.

MATERIALS AND METHODS

Neonatal mice were exposed to the hypoxic-ischemic brain damage (HIBD) model to determine brain water content, and brain tissue was subjected to hematoxylin and eosin (HE), immunohistochemistry (IHC), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and Nissl staining to investigate its neuroprotective effects. Furthermore, the neonatal mouse primary neuron oxygen-glucose deprivation (OGD) model to measure reactive oxygen species (ROS) production in vitro. The protein levels were characterized by Western Blot, and mRNA levels were evaluated by a real-time quantitative PCR detecting system (qPCR). Transmission electron microscopy (TEM) and mitochondrial fluorescent staining were used to observe mitochondrial morphology. Neuronal nuclei (NeuN) and microtubule-associated protein 2 (MAP2) were detected by Immunofluorescence (IF). Finally, network pharmacology was employed to determine the common target of naringenin and HIE. The core genes were obtained via protein-protein interaction networks (PPI) analysis and molecular docking was examined, and the mechanism of action was explored through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Additionally, small interfering RNA (siRNA) was constructed for verification.

RESULTS

Naringenin has a neuroprotective effect in HIBD by modulating Vegfa expression and activating the PI3K/AKT pathway to inhibit apoptosis. Furthermore, molecular docking results suggest that Vegfa is a potential binding target of naringenin, and silencing Vegfa partially reverses the pharmacological effects of NGN.

CONCLUSION

Our findings suggest that naringenin demonstrates potential clinical application for treating HIE as a novel neuroprotective agent.

Microcystin-LR prenatal exposure drives preeclampsia-like changes in mice by inhibiting the expression of TGF-β and VEGFA

Microcystin-leucine-arginine (MC-LR) is widespread in the water and food, which has suspected to be associated with adverse pregnancy outcomes. In the present study, we aim to assess the interaction between MC-LR exposure and preeclampsia development and elucidate the molecular events involved. After exposure to MC-LR during pregnancy, the mice developed hypertension and proteinuria, the typical symptoms of preeclampsia. This was associated with decreased invasiveness of placental trophoblast and vascular dysplasia caused by MC-LR through down-regulating VEGFA and TGF-β expression via AKT/m-TOR/HIF-1α pathway. In addition, this conclusion has been confirmed in a case-control study. Significantly, the addition of Deferoxamine (DFM), a phosphorylated serine-threonine protein kinases (p-AKT) specific agonist, can antagonize the inhibitory effect of MC-LR on the expression of related proteins, which further ameliorate the migration and invasion ability of HTR-8/Svneo cells. To sum up, our study revealed the pathologic mechanism by which MC-LR lead to preeclampsia and emphasized the importance of pregnancy management.

Cardamonin mitigates kidney injury by modulating inflammation, oxidative stress, and apoptotic signaling in rats subjected to renal ischemia and reperfusion

Renal ischemia-reperfusion injury (IRI) is a critical health concern that aggravates the pathophysiology of acute kidney injury (AKI), leading to high mortality rates in intensive care units. Cardamonin is a natural compound with anti-inflammatory and antioxidant properties. The current study aimed to evaluate the renoprotective impact of cardamonin against AKI induced by renal IRI. Male rats (n=5 per group) were divided into four groups: the sham group underwent anesthesia and abdominal incision only; the control group experienced bilateral renal artery clamping for 30 minutes followed by 2 hours of reperfusion; the vehicle group received the cardamonin vehicle 30 minutes before ischemia induction; and the cardamonin group was administered 5 mg/kg of cardamonin 30 minutes before ischemia. Blood urea nitrogen (BUN) and creatinine were measured to assess the renal function. Tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1β), interleukin-6 (IL-6), caspase 3, and F2-isoprostane were assessed in renal tissues. Kidney injury was examined using the hematoxylin and eosin stain method. Compared to the sham group, the control group exhibited significantly higher levels of BUN, creatinine, TNF-α, IL-1β, IL-6, F2-isoprostane, and caspase 3 in renal tissues, along with severe kidney injury as evidenced by histological analysis. Compared to the control group, pretreatment with cardamonin resulted in a significant reduction in these biomarkers and alleviated renal damage. Cardamonin had renoprotective effects against renal ischemia and reperfusion injury via modulating inflammation, oxidative stress, and apoptosis pathways.

Pyruvate dehydrogenase kinase 1 protects against neuronal injury and memory loss in mouse models of diabetes

Hyperglycemia-induced aberrant glucose metabolism is a causative factor of neurodegeneration and cognitive impairment in diabetes mellitus (DM) patients. The pyruvate dehydrogenase kinase (PDK)-lactic acid axis is regarded as a critical link between metabolic reprogramming and the pathogenic process of neurological disorders. However, its role in diabetic neuropathy remains unclear. Here, we found that PDK1 and phosphorylation of pyruvate dehydrogenase (PDH) were obviously increased in high glucose (HG)-stimulated primary neurons and Neuro-2a cell line. Acetyl-coA, a central metabolic intermediate, might enhance PDK1 expression via histone H3K9 acetylation modification in HG condition. The epigenetic regulation of PDK1 expression provided an available negative feedback pattern in response to HG environment-triggered mitochondrial metabolic overload. However, neuronal PDK1 was decreased in the hippocampus of streptozotocin (STZ)-induced diabetic mice. Our data showed that the expression of PDK1 also depended on the hypoxia-inducible factor-1 (HIF-1) transcriptional activation under the HG condition. However, HIF-1 was significantly reduced in the hippocampus of diabetic mice, which might explain the opposite expression of PDK1 in vivo. Importantly, overexpression of PDK1 reduced HG-induced reactive oxygen species (ROS) generation and neuronal apoptosis. Enhancing PDK1 expression in the hippocampus ameliorated STZ-induced cognitive impairment and neuronal degeneration in mice. Together, our study demonstrated that both acetyl-coA-induced histone acetylation and HIF-1 are necessary to direct PDK1 expression, and enhancing PDK1 may have a protective effect on cognitive recovery in diabetic mice. Schematic representation of the protective effect of PDK1 on hyperglycemia-induced neuronal injury and memory loss. High glucose enhanced the expression of PDK1 in an acetyl-coA-dependent histone acetylation modification to avoid mitochondrial metabolic overload and ROS release. However, the decrease of HIF-1 may impair the upregulation of PDK1 under hyperglycemia condition. Overexpression of PDK1 prevented hyperglycemia-induced hippocampal neuronal injury and memory loss in diabetic mice.

Catalpol Alleviates Ischemic Stroke Through Promoting Angiogenesis and Facilitating Proliferation and Differentiation of Neural Stem Cells via the VEGF-A/KDR Pathway

Stroke is one of the leading causes of disability and death globally with a lack of effective therapeutic strategies. Catalpol is a bioactive compound derived from the traditional Chinese medicine Rehmannia glutinosa and it has been shown to be protective against various neurological diseases. The potential roles of catalpol against ischemic stroke are still not completely clear. In this study, we examined the effect and mechanism of catalpol against ischemic stroke using in vivo rat distal middle cerebral artery occlusion (dMCAO) and in vitro oxygen-glucose deprivation (OGD) models. We demonstrated that catalpol indeed attenuated the neurological deficits caused by dMCAO and improved neurological function. Catalpol remarkably promoted angiogenesis, promoted proliferation and differentiation of neural stem cells (NSCs) in the subventricular zone (SVZ), and prevented neuronal loss and astrocyte activation in the ischemic cortex or hippocampal dentate gyrus (DG) in vivo. The vascular endothelial growth factor receptor 2 (KDR, VEGFR-2) inhibitor SU5416 and VEGF-A shRNA were used to investigate the underlying mechanisms. The results showed that SU5416 administration or VEGF-A-shRNA transfection both attenuated the effects of catalpol. We also found that catalpol promoted the proliferation of cultured brain microvascular endothelial cells (BMECs) and the proliferation and differentiation of NSCs subjected to OGD insult in vitro. Interestingly, the impact of catalpol on cultured cells was also inhibited by SU5416. Moreover, catalpol was shown to protect NSCs against OGD indirectly by promoting BMEC proliferation in the co-cultured system. Taken together, catalpol showed therapeutic potential in cerebral ischemia by promoting angiogenesis and NSC proliferation and differentiation. The protective effects of catalpol were mediated through VEGF-A/KDR pathway activation.

DEXMEDETOMIDINE AMELIORATES ACUTE BRAIN INJURY INDUCED BY MYOCARDIAL ISCHEMIA-REPERFUSION VIA UPREGULATING THE HIF-1 PATHWAY

ABSTRACT

Objective: Neurological complications after myocardial ischemia/reperfusion (IR) injury remain high and seriously burden patients and their families. Dexmedetomidine (Dex), an α 2 agonist, is endowed with analgesic-sedative and anti-inflammatory effects. Therefore, our study aims to explore the mechanism and effect of Dex on brain damage after myocardial IR injury. Methods C57BL/6 mice were randomly divided into sham, IR, and IR + Dex groups, and myocardial IR models were established. The impact of Dex on brain injury elicited by myocardial IR was assessed via ELISA for inflammatory factors in serum and brain; Evans blue for blood-brain barrier permeability; hematoxylin-eosin staining for pathological injury in brain; immunofluorescence for microglia activation in brain; Morris water maze for cognitive dysfunction; western blot for the expression level of HIF-1α, occludin, cleaved caspase-3, NF-κB p65, and p-NF-κB p65 in the brain. In addition, HIF-1α knockout mice were used to verify whether the neuroprotective function of Dex is associated with the HIF-1 pathway. Results: Dex was capable of reducing myocardial IR-induced brain damage including inflammatory factor secretion, blood-brain barrier disruption, neuronal edema, microglial activation, and acute cognitive dysfunction. However, the protective role of Dex was attenuated in HIF-1α knockout mice. Conclusion: Dex protects against myocardial IR-induced brain injury, and the neuroprotection of Dex is at least partially dependent on the activation of the HIF-1 pathway.

HIF-1, an important regulator in potential new therapeutic approaches to ischemic stroke

Ischemic stroke is a leading cause of disability and mortality worldwide due to the narrow therapeutic window of the only approved therapies like intravenous thrombolysis and thrombectomy. Hypoxia inducible factor-1α (HIF-1α) is a sensitive regulator of oxygen homeostasis, and its expression is rapidly induced after hypoxia/ischemia. It plays an extensive role in the pathophysiology of stroke by regulating multiple pathways including glucose metabolism, angiogenesis, neuronal survival, neuroinflammation and blood brain barrier regulation. Here, we give a brief overview of the HIF-1α-targeting strategies currently under investigation and summarise recent research on how HIF-1α is regulated in various brain cells, including neurons and microglia, at various stages in ischemic stroke. The roles of HIF-1 in stroke varies with ischemic time and degree of ischemia, are still up for debate. More focus has been placed on prospective HIF-1α targeting drugs, such as HIF-1α activator, HIF-1α stabilizers, and natural compounds. In this review, we have highlighted the regulation of HIF-1α in the novel therapeutic approaches for treatment of stroke.

Role of traditional Chinese medicine monomers in cerebral ischemia/reperfusion injury:a review of the mechanism

Ischemia/reperfusion (I/R) injury is a pathological process wherein reperfusion of an ischemic organ or tissue exacerbates the injury, posing a significant health threat and economic burden to patients and their families. I/R triggers a multitude of physiological and pathological events, such as inflammatory responses, oxidative stress, neuronal cell death, and disruption of the blood-brain barrier (BBB). Hence, the development of effective therapeutic strategies targeting the pathological processes resulting from I/R is crucial for the rehabilitation and long-term enhancement of the quality of life in patients with cerebral ischemia/reperfusion injury (CIRI). Traditional Chinese medicine (TCM) monomers refer to bioactive compounds extracted from Chinese herbal medicine, possessing anti-inflammatory and antioxidative effects, and the ability to modulate programmed cell death (PCD). TCM monomers have emerged as promising candidates for the treatment of CIRI and its subsequent complications. Preclinical studies have demonstrated that TCM monomers can enhance the recovery of neurological function following CIRI by mitigating oxidative stress, suppressing inflammatory responses, reducing neuronal cell death and functional impairment, as well as minimizing cerebral infarction volume. The neuroprotective effects of TCM monomers on CIRI have been extensively investigated, and a comprehensive understanding of their mechanisms can pave the way for novel approaches to I/R treatment. This review aims to update and summarize evidence of the protective effects of TCMs in CIRI, with a focus on their role in modulating oxidative stress, inflammation, PCD, glutamate excitotoxicity, Ca2+ overload, as well as promoting blood-brain barrier repairment and angiogenesis. The main objective is to underscore the significant contribution of TCM monomers in alleviating CIRI.

Chrysin protects against cerebral ischemia-reperfusion injury in hippocampus via restraining oxidative stress and transition elements

Chrysin is a natural flavonoid compound that has antioxidant and neuroprotective effects. Cerebral ischemia reperfusion (CIR) is closely connected with increased oxidative stress in the hippocampal CA1 region and homeostasis disorder of transition elements such as iron (Fe), copper (Cu) and zinc (Zn). This exploration was conducted to elucidate the antioxidant and neuroprotective effects of chrysin based on transient middle cerebral artery occlusion (tMCAO) in rats. Experimentally, sham group, model group, chrysin (50.0 mg/kg) group, Ginaton (21.6 mg/kg) group, Dimethyloxallyl Glycine (DMOG, 20.0 mg/kg) + chrysin group and DMOG group were devised. The rats in each group were performed to behavioral evaluation, histological staining, biochemical kit detection, and molecular biological detection. The results indicated that chrysin restrained oxidative stress and the rise of transition element levels, and regulated transition element transporter levels in tMCAO rats. DMOG activated hypoxia-inducible factor-1 subunit alpha (HIF-1α), reversed the antioxidant and neuroprotective effects of chrysin, and increased transition element levels. In a word, our findings emphasize that chrysin plays a critical role in protecting CIR injury via inhibiting HIF-1α against enhancive oxidative stress and raised transition metal levels.

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

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

Exploring the synergic mechanism of Ligusticum striatum DC. and borneol in attenuating BMECs injury and maintaining tight junctions against cerebral ischaemia based on the HIF-1α/VEGF signalling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Ligusticum striatum DC., also known as Ligusticum chuanxiong Hort. (LCH), is widely used in China for its excellent effect in ischaemic stroke (IS) patients, and borneol (BO) has been confirmed to maintain the blood‒brain barrier (BBB) after stroke. They are often used as a combination in the prescriptions of IS patients. Although the advantage of their combined treatment in improving brain ischaemia has been verified, their synergistic mechanism on BBB maintenance is still unclear.

AIM OF THE STUDY

This study was designed to evaluate the synergistic effect of maintaining the BBB between LCH and BO against IS and to further explore the potential mechanism.

MATERIALS AND METHODS

After primary mouse brain microvascular endothelial cells (BMECs) were extracted and identified, the duration of oxygen-glucose deprivation (OGD) and the doses of LCH and BO were optimized. Then, the cells were divided into five groups: control, model, LCH, BO, and LCH + BO. Cell viability, injury degree, proliferation and migration were detected by CCK-8, LDH, EdU and wound-healing assays, respectively. Hoechst 33342 staining was adopted to detect the apoptosis rate, and western blotting was employed to observe the expressions of Bax, Bcl-2, caspase-3 and cleaved caspase-3. The TEER value and NaF permeability were measured to assess tight junction (TJ) function, while ZO-1, occludin and claudin-5 were also probed by western blotting. Moreover, the HIF-1α/VEGF pathway was observed to explore the underlying mechanism of BBB maintenance. In vivo, global cerebral ischaemia/reperfusion (GCIR) surgery was performed to establish an IS model. After treatment with LCH (200 mg/kg) and/or BO (160 mg/kg), histopathological structure and BMECs repair were observed by HE staining and immunohistochemistry of vWF. Meanwhile, TJ-associated proteins in vivo were also detected by western blotting.

RESULTS

Basically, LCH and BO had different emphases. LCH significantly attenuated the vacuolar structure, nuclear pyknosis and neuronal loss of GCIR mice, while BO focused on promoting BMECs proliferation and angiogenesis and inhibiting the degradation of TJ-associated proteins in vivo after IS. Interestingly, their combination further enhanced these effects. OGD injury markedly reduced the viability, proliferation and migration of primary BMECs; decreased the ratio of Bcl-2/Bax, TEER value, and the expressions of ZO-1, occludin and claudin-5; induced LDH release and apoptosis; and increased the cleaved caspase-3/caspase-3 ratio and NaF permeability. Meanwhile, BO might be the main contributor to the combinative treatment in ameliorating OGD-induced damage of BMECs and degradation of TJ-related proteins, and the potential mechanism might be involved in upregulating the HIF-1α/VEGF signalling pathway. Although LCH showed no obvious improvement, it could enhance the therapeutic effect of BO. Interestingly, their combination even produced some new improvements, including the reduction of cleaved caspase-3 and increase in TEER value, none of which were exhibited in their monotherapies.

CONCLUSIONS

LCH and BO exhibited complementary therapeutic features in alleviating cerebral ischaemic injury by inhibiting BMECs apoptosis, maintaining the BBB and attenuating the loss of neurons. LCH preferred to protect ischaemic neurons, while BO played a key role in protecting BMECs, maintaining the BBB and TJs by activating the HIF-1α/VEGF signalling pathway.

Chlorogenic acid promotes angiogenesis and attenuates apoptosis following cerebral ischaemia-reperfusion injury by regulating the PI3K-Akt signalling

CONTEXT

Chlorogenic acid (CGA) has good antioxidant effects, but its explicit mechanism in cerebral ischaemia-reperfusion injury is still uncertain.

OBJECTIVE

We studied the effect of CGA in human brain microvascular endothelial cells (HBMECs) under OGD/R damage.

MATERIALS AND METHODS

HBMECs in 4 groups were treated with oxygen-glucose deprivation/re-oxygenation (OGD/R) (4 + 24 h), normal no CGA treatment and different concentrations (20, 40 or 80 μM) of CGA. Male C57BL/6J mice were classified as sham, middle cerebral artery occlusion (MCAO), and MCAO + CGA (30 mg/kg/day) groups. Mice in the sham group were not subjected to MCAO. Cell viability, apoptosis, angiogenesis and related protein levels were investigated by CCK-8, flow cytometry, TUNEL staining, tube formation and western blot assays. Infarct volume of brain tissues was analyzed by TTC staining.

RESULTS

CGA curbed apoptosis (from 32.87% to 13.12% in flow cytometry; from 34.46% to 17.8% in TUNEL assay) but accelerated cell angiogenesis of HBMECs with OGD/R treatment. Moreover, CGA augmented activation of the PI3K-Akt signalling (p-PI3K/PI3K level, from 0.39 to 0.49; p-Akt/Akt level, from 0.52 to 0.81), and the effect of CGA on apoptosis and angiogenesis was abolished by an inhibitor of PI3K-Akt signalling. Furthermore, CGA attenuated infarct (from 41.26% to 22.21%) and apoptosis and promoted angiogenesis and activation of the PI3K/Akt signalling in MCAO-induced mice.

CONCLUSIONS

CGA effectively repressed apoptosis and promoted angiogenesis in OGD/R-treated HBMECs and MCAO-treated mice by modulating PI3K-Akt signalling. Our research provides a theoretical basis for the use of CGA in the treatment of ischaemic stroke.

Buyang Huanwu decoction promotes angiogenesis of rat brain microvascular endothelial cells after oxygen-glucose deprivation reperfusion injury via activation of PI3K-AKT signaling pathway

OBJECTIVE

To investigate the effect and mechanism of Buyang Huanwu decoction (BYHWD) on angiogenesis of rat brain microvascular endothelial cells (RBMECs) after oxygen-glucose deprivation reperfusion (OGD/R) injury.

METHODS

RBMECs were pretreated with BYHWD containing serum 24 h before OGD/R injury was induced. Cells were randomly divided into blank control group, model control group, BYHWD group (provided BYHWD containing serum) and LY294002 group [treated with phosphoinositide 3-kinase (PI3K) inhibitor LY294002 for 1 h before provided BYHWD containing serum]. The cell viability, migration and tube formation abilities of RBMECs were detected by CCK-8, scratch wound healing, Transwell migration and tube formation assays, respectively. The protein expression levels of PI3K, p-PI3K, protein kinase B (AKT), p-AKT, hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) were determined by Western blotting.

RESULTS

Compared with model control group, cell viability, migration and tube formation abilities of RBMECs were significantly improved in BYHWD group (all P<0.01), the protein expression levels of p-PI3K, p-AKT, HIF-1α and VEGF were up-regulated (all P<0.05); while above effects were blocked by LY294002.

CONCLUSION

BYHWD can promote angiogenesis of RBMECs after OGD/R injury, which may be related to the increased protein expression of HIF-1α and VEGF through activation of PI3K-AKT signaling pathway.

N6-methyladenosine-modified lncRNA and mRNA modification profiles in cerebral ischemia-reperfusion injury

Cerebral ischemia-reperfusion injury (CIRI) is common in ischemic stroke and seriously affects the prognosis of patients. At present, N6-methyladenosine (m6A) modification of lncRNAs and mRNAs has been reported in other diseases, such as cancer, but its role in CIRI has not been clarified. In this study, we aimed to investigate the m6A lncRNA and m6A mRNA modification profiles in CIRI. First, we detected the total level of m6A and the changes in related m6A methyltransferases and demethylases in the brain tissue of rats with CIRI and then identified differentially modified lncRNAs and mRNAs in CIRI by lncRNA and mRNA epigenetic transcriptomic microarray. In addition, bioinformatics analysis was used to predict the underlying functions and related pathways of related lncRNAs and mRNAs. We found that the total m6A methylation level was significantly increased, and the expression of fat mass and obesity-associated protein (FTO) was downregulated after CIRI. In addition, a large number of m6A-modified lncRNAs and mRNAs appeared after CIRI, and these genes were mainly enriched for the Toll-like receptor signaling pathway, peroxisome proliferator-activated receptor (PPAR) signaling pathway, and mitogen-activated protein kinase (MAPK) signaling pathway. Our findings provide the basis and insights for further studies on m6A modification in CIRI.

The importance of natural chalcones in ischemic organ damage: Comprehensive and bioinformatic analysis review

Over the last few decades, extensive research has been conducted, yielding a detailed account of thousands of newly discovered compounds of natural origin and their biological activities, all of which have the potential to be used for a wide range of therapeutic purposes. There are multiple research papers denoting the central objective of chalcones, which have been shown to have therapeutic potential against various forms of ischemia. The various aspects of chalcones are discussed in this review regarding molecular mechanisms involved in the promising anti-ischemic potential of these chalcones. The main mechanisms involved in these protective effects are Nrf2/Akt activation and NF-κB/TLR4 suppression. Furthermore, in-silico studies were carried out to discover the probable binding of these chalcones to Keap-1 (an inhibitor of Nrf2), Akt, NF-κB, and TLR4 protein molecules. Besides, network pharmacology analysis was conducted to predict the interacting partners of these signals. The obtained results indicated that Nrf2, Akt, NF-κB, and TLR4 are involved in the beneficial anti-ischemic actions of chalcones. Conclusively, the present findings show that chalcones as anti-ischemic agents have a valid rationale. The discussed studies will provide a comprehensive viewpoint on chalcones and can help to optimize their effects in different ischemia. PRACTICAL APPLICATIONS: Ischemic organ damage is an unavoidable pathological condition with a high worldwide incidence. According to the current research progress, natural chalcones have been proved to treat and/or prevent various types of ischemic organ damage by alleviating oxidative stress, inflammation, and apoptosis by different molecular mechanisms. This article displays the comprehensive research progress and the molecular basis of ischemic organ damage pathophysiology and introduces natural chalcones' mechanism in the ischemic organ condition.

The Signaling Pathways and Targets of Natural Compounds from Traditional Chinese Medicine in Treating Ischemic Stroke

Ischemic stroke (IS) is a common neurological disorder associated with high disability rates and mortality rates. At present, recombinant tissue plasminogen activator (r-tPA) is the only US(FDA)-approved drug for IS. However, due to the narrow therapeutic window and risk of intracerebral hemorrhage, r-tPA is currently used in less than 5% of stroke patients. Natural compounds have been widely used in the treatment of IS in China and have a wide range of therapeutic effects on IS by regulating multiple targets and signaling pathways. The keywords "ischemia stroke, traditional Chinese Medicine, Chinese herbal medicine, natural compounds" were used to search the relevant literature in PubMed and other databases over the past five years. The results showed that JAK/STAT, NF-κB, MAPK, Notch, Nrf2, and PI3K/Akt are the key pathways, and SIRT1, MMP9, TLR4, HIF-α are the key targets for the natural compounds from traditional Chinese medicine in treating IS. This study aims to update and summarize the signaling pathways and targets of natural compounds in the treatment of IS, and provide a base of information for the future development of effective treatments for IS.