Effect of fluoxetine on HIF-1α- Netrin/VEGF cascade, angiogenesis and neuroprotection in a rat model of transient middle cerebral artery occlusion

Electroacupuncture ameliorates cognitive impairment and white matter injury in vascular dementia rats via activating HIF-1α/VEGF/VEGFR2 pathway

Vascular dementia (VaD) significantly impairs patients' quality of life and imposes a major social and economic burden. Electroacupuncture (EA), a contemporary modification of traditional acupuncture, has demonstrated potential in improving cognitive function in VaD, particularly when applied at the Shenting and Baihui. However, the underlying mechanisms remain inadequately understood. Elucidating how EA ameliorates cognitive deficits is critical for validating its clinical application and advancing non-pharmacological interventions for neurodegenerative disorders. This study aimed to investigate the neuroprotective mechanisms of electroacupuncture at these acupoints on cognitive function in VaD rats. VaD was induced in male Sprague-Dawley rats through bilateral common carotid artery occlusion (BCAO), with sham rats serving as controls. Rats were subsequently divided into three groups: BCAO, BCAO + EA and BCAO + EA + YC-1 (a HIF-1α inhibitor). Electroacupuncture was applied to the Shenting and Baihui. Cerebral blood flow (CBF) was measured using dynamic susceptibility contrast functional MRI, and cognitive recovery was evaluated through the Morris water maze. Immunohistochemical analysis quantified myelin repair and angiogenesis, while expression of HIF-1α, VEGF and VEGFR2 in white matter was quantified using PCR and Western blot. The results indicated that electroacupuncture improved learning and memory, increased CBF, enhanced myelin recovery and promoted angiogenesis in VaD rats. The expression of HIF-1α, VEGF and VEGFR2 in the white matter was significantly elevated in VaD rats. Electroacupuncture at Shenting and Baihui activates the HIF-1α/VEGF/VEGFR2 pathway, enhances angiogenesis, white matter perfusion and myelin repair, thereby restoring cognitive function in VaD rats.

Dexmedetomidine Promotes Angiogenesis After Ischemic Stroke Through the NRF2/HO-1/VEGF Pathway

Neurological dysfunction following stroke presents a significant challenge for patients. Recent studies suggest that angiogenesis can improve neurological function and enhance neuronal survival after ischemic stroke. Dexmedetomidine exhibits neuroprotective effects through various mechanisms; therefore, this study aimed to investigate whether it promotes angiogenesis and improves neurological function after stroke. A mouse model of ischemic stroke was developed by embolizing the middle cerebral arteries. Neurological function was assessed using scoring methods, the water maze test, and histological analyses, including Nissl and hematoxylin and eosin staining, to evaluate neuronal survival in the ischemic penumbra. Angiogenesis was observed through immunofluorescence staining, whereas pathway protein expression was analyzed via western blotting. Additionally, a model of oxygen-glucose deprivation/reoxygenation was established in mouse cerebral microvascular cells to conduct angiogenesis-related experiments. Dexmedetomidine reduced cerebral infarction size, alleviated neurological damage, promoted angiogenesis in the ischemic penumbra, and decreased neuronal death through the Nrf2/HO-1/VEGF pathway. However, these neuroprotective effects were reversed by the NRF2 inhibitor ML385. In vitro, dexmedetomidine enhanced the proliferation, migration, and tube-formation of cerebral microvascular cells in mice. ML385 also reversed the protective effects of dexmedetomidine against hypoxia and glucose deprivation-induced axonal damage. Dexmedetomidine enhances angiogenesis, reduces neuronal damage, and promotes cerebral microvascular cell migration and tube formation in the ischemic penumbra of an ischemic stroke mouse model through the Nrf2/HO-1/VEGF pathway.

Fluoxetine promotes the recovery of dysphagia and improves nutritional status and neurotrophic status in dysphagia patients after acute ischemic stroke

This study aimed to investigate the effects of fluoxetine on swallowing function, neurotrophic factors, and psychological status in patients with dysphagia after acute ischemic stroke (AIS). A total of 118 patients with dysphagia after AIS who were diagnosed and treated in our hospital from July 2020 to March 2022 were selected as the study objects with 59 cases in each group. Patients in the control group underwent routine treatment and swallowing rehabilitation without fluoxetine. Patients in the study group received routine treatment, swallowing rehabilitation, and fluoxetine treatment. The quality of life was compared according to the Generic Quality of Life Inventory-74 (CQOLI-74). Patients were followed for 90 days, and the grades were compared with the Modified Rankin Scale (mRS). The total effective rate of the study group was 84.75%, which was higher than that of the control group with 62.71% (χ2 = 7.394, P < 0.05). The life quality scores of the two groups were both dramatically elevated compared to those before the treatment, and the study group had a sensibly higher life quality score than the control group (P < 0.05). The proportion of grade 4~5 in the study group was significantly lower than that in the control group (χ2 = 492, P < 0.05). The total incidence of adverse reactions in the control group was 5.08% (3/59), which was significantly lower than that in the study group with 11.86% (7/59) (χ2 = 1.748, P = 0.186). Fluoxetine has a significant effect on the treatment of dysphagia after AIS by enhancing the recovery of dysphagia and promoting the recovery of neurological function.

Hif-1α ablation reduces the efficiency of NeuroD1 gene-based therapy and aggravates the brain damage following ischemic stroke

INTRODUCTION

Hypoxia-inducible factor 1α [HIF1α] regulates gene expression, allowing the organism to respond to low oxygen levels. Meanwhile, astrocytes participate in inflammatory processes and are associated with neurotoxic chemicals that can increase stroke volume, contributing considerably to the devastating effects of a stroke.

OBJECTIVE

To evaluate whether Hif-1α ablation from the central nervous system is implicated in motor dysfunction and ischemic brain damage following stroke. Furthermore, to explore if Hif-1α ablation affects the therapeutic impact of NeuroD1 gene-based therapy.

METHODS

Endothelin-1 [ET-1] was injected to induce ischemic stroke in mice. Both wild-type and Hypoxia-inducible factor 1α conditional knockout [Hif-1α CKO] mice were used. The effect of Hif-1α ablation was assessed by the neuron numbers, astrocyte activity, vascular endothelial growth factor [VEGF] expression, and behavioral tests. Moreover, western blot, ELISA, and RNA sequencing were used. Then, we used pAAV2/9-GfaABC1D-NeuroD1-P2A-EGFP-WPRE injection to examine the impact of NeuroD1 in Hif-1α CKO mice following ischemic stroke.

RESULTS

We found that following stroke, motor dysfunction significantly increased in Hif-1α CKO mice. Furthermore, elevation of apoptosis and activation in both microglia and astrocytes were observed, consequently up-regulating neuroinflammation. Meanwhile, Hif-1α ablation significantly decreased the efficiency of NeuroD1 gene-based therapy.

CONCLUSION

Our findings demonstrate that Hif-1α ablation from the nervous system is implicated in ischemic stroke pathogenesis mainly by increasing neuron cell death and inducing astrocytes as well as decreasing the efficiency of NeuroD1. These data support the idea that manipulating HIF-1α is a viable therapeutic for ischemic stroke.

Mechanisms of Postischemic Stroke Angiogenesis: A Multifaceted Approach

Ischemic stroke constitutes a significant global health care challenge, and a comprehensive understanding of its recovery mechanisms is imperative for the development of innovative therapeutic strategies. Angiogenesis, a pivotal element of ischemic tissue repair, facilitates the restoration of blood flow to damaged regions, thereby promoting neuronal regeneration and functional recovery. Nevertheless, the mechanisms underlying postischemic stroke angiogenesis remain incompletely elucidated. This review meticulously examines the constituents of the neurovascular unit, ion channels, molecular mediators, and signaling pathways implicated in angiogenesis following stroke. Furthermore, it delves into prospective therapeutic strategies informed by these factors. Our objective is to provide detailed and exhaustive information on the intricate mechanisms governing postischemic stroke angiogenesis, thus providing a robust scientific foundation for the advancement of novel neurorepair therapies.

The Janus face of HIF-1α in ischemic stroke and the possible associated pathways

Stroke is the most devastating disease, causing paralysis and eventually death. Many clinical and experimental trials have been done in search of a new safe and efficient medicine; nevertheless, scientists have yet to discover successful remedies that are also free of adverse effects. This is owing to the variability in intensity, localization, medication routes, and each patient's immune system reaction. HIF-1α represents the modern tool employed to treat stroke diseases due to its functions: downstream genes such as glucose metabolism, angiogenesis, erythropoiesis, and cell survival. Its role can be achieved via two downstream EPO and VEGF strongly related to apoptosis and antioxidant processes. Recently, scientists paid more attention to drugs dealing with the HIF-1 pathway. This review focuses on medicines used for ischemia treatment and their potential HIF-1α pathways. Furthermore, we discussed the interaction between HIF-1α and other biological pathways such as oxidative stress; however, a spotlight has been focused on certain potential signalling contributed to the HIF-1α pathway. HIF-1α is an essential regulator of oxygen balance within cells which affects and controls the expression of thousands of genes related to sustaining homeostasis as oxygen levels fluctuate. HIF-1α's role in ischemic stroke strongly depends on the duration and severity of brain damage after onset. HIF-1α remains difficult to investigate, particularly in ischemic stroke, due to alterations in the acute and chronic phases of the disease, as well as discrepancies between the penumbra and ischemic core. This review emphasizes these contrasts and analyzes the future of this intriguing and demanding field.

Selenization of Small Molecule Drugs: A New Player on the Board

There is an urgent need to develop safer and more effective modalities for the treatment of a wide range of pathologies due to the increasing rates of drug resistance, undesired side effects, poor clinical outcomes, etc. Throughout the years, selenium (Se) has attracted a great deal of attention due to its important role in human health. Besides, a growing body of work has unveiled that the inclusion of Se motifs into a great number of molecules is a promising strategy for obtaining novel therapeutic agents. In the current Perspective, we have gathered the most recent literature related to the incorporation of different Se moieties into the scaffolds of a wide range of known drugs and their feasible pharmaceutical applications. In addition, we highlight different representative examples as well as provide our perspective on Se drugs and the possible future directions, promises, opportunities, and challenges of this ground-breaking area of research.

Compound Shenma Jingfu granule alleviates cerebral ischemia via HIF-1α-mediated promotion of angiogenesis

BACKGROUND

Shenma Jingfu Granule, a traditional Chinese medicine formula, has been used clinically for the treatment of cerebral circulation insufficiency. However, the mechanism involved in alleviating cerebral ischemia has not yet been fully elucidated.

METHODS

An integrated approach involving network pharmacology and transcriptomics was utilized to clarify the potential mechanisms of SMJF Granule. Molecular docking and surface plasmon resonance (SPR) were employed to identify potential targets and ingredients of SMJF Granule. The anti-CI effect of SMJF Granule was determined on the middle cerebral artery occlusion (MCAO) model by using hematoxylin-eosin (H&E) and Nissl's staining, as well as triphenyl tetrazolium chloride (TTC) staining, and the potential targets involved in the mechanisms were validated by RT-qPCR and western blotting.

RESULTS

Integrated analysis revealed the mechanism of SMJF Granule intervening in CI injury might be related to the HIF-1 signaling pathway and angiogenesis. Molecular docking and SPR assays demonstrated robust binding interactions between key compounds like salvianolic acid A and naringenin with the core target HIF-1α protein. The experiment confirmed that SMJF Granule lowered neurological scores, diminished infarct volume, and alleviated histopathological changes in vivo. The possible mechanism of SMJF Granule was due to regulating HIF-1 pathway, which contributed to up-regulating expression of VEGF and vWF in the penumbral region, showing a significant promotion of angiogenesis.

CONCLUSION

SMJF Granule promoted angiogenesis through HIF-1α pathway, thereby alleviating cerebral ischemia injury. In addition, our findings provide some evidence that SMJF Granule is a candidate compound for further investigation in treating CI in the clinical.

A comprehensive review of stroke-related signaling pathways and treatment in western medicine and traditional Chinese medicine

This review provides insight into the complex network of signaling pathways and mechanisms involved in stroke pathophysiology. It summarizes the historical progress of stroke-related signaling pathways, identifying potential interactions between them and emphasizing that stroke is a complex network disease. Of particular interest are the Hippo signaling pathway and ferroptosis signaling pathway, which remain understudied areas of research, and are therefore a focus of the review. The involvement of multiple signaling pathways, including Sonic Hedgehog (SHH), nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE), hypoxia-inducible factor-1α (HIF-1α), PI3K/AKT, JAK/STAT, and AMPK in pathophysiological mechanisms such as oxidative stress and apoptosis, highlights the complexity of stroke. The review also delves into the details of traditional Chinese medicine (TCM) therapies such as Rehmanniae and Astragalus, providing an analysis of the recent status of western medicine in the treatment of stroke and the advantages and disadvantages of TCM and western medicine in stroke treatment. The review proposes that since stroke is a network disease, TCM has the potential and advantages of a multi-target and multi-pathway mechanism of action in the treatment of stroke. Therefore, it is suggested that future research should explore more treasures of TCM and develop new therapies from the perspective of stroke as a network disease.

Cure of Alzheimer's Dementia Requires Addressing All of the Affected Brain Cell Types

Multiple genetic, metabolic, and environmental abnormalities are known to contribute to the pathogenesis of Alzheimer's dementia (AD). If all of those abnormalities were addressed it should be possible to reverse the dementia; however, that would require a suffocating volume of drugs. Nevertheless, the problem may be simplified by using available data to address, instead, the brain cells whose functions become changed as a result of the abnormalities, because at least eleven drugs are available from which to formulate a rational therapy to correct those changes. The affected brain cell types are astrocytes, oligodendrocytes, neurons, endothelial cells/pericytes, and microglia. The available drugs include clemastine, dantrolene, erythropoietin, fingolimod, fluoxetine, lithium, memantine, minocycline, pioglitazone, piracetam, and riluzole. This article describes the ways by which the individual cell types contribute to AD's pathogenesis and how each of the drugs corrects the changes in the cell types. All five of the cell types may be involved in the pathogenesis of AD; of the 11 drugs, fingolimod, fluoxetine, lithium, memantine, and pioglitazone, each address all five of the cell types. Fingolimod only slightly addresses endothelial cells, and memantine is the weakest of the remaining four. Low doses of either two or three drugs are suggested in order to minimize the likelihood of toxicity and drug-drug interactions (including drugs used for co-morbidities). Suggested two-drug combinations are pioglitazone plus lithium and pioglitazone plus fluoxetine; a three-drug combination could add either clemastine or memantine. Clinical trials are required to validate that the suggest combinations may reverse AD.

Isolation and identification of angiogenesis-promoting components in Huanglian Jiedu decoction using live cell bio-specific extraction

ETHNOPHARMACOLOGICAL RELEVANCE

Huanglian Jiedu Decoction (HLJDD) is a traditional heat-dissipating and detoxicating prescription used in Chinese medicine and has been extensively applied in the clinical treatment of ischemic stroke. Preliminary research confirmed that HLJDD exerts a neuroprotective effect on brain tissue injury caused by cerebral ischemia by promoting angiogenesis. However, the components of HLJDD responsible for its medicinal activity in ischemic injury remain unclear.

AIM OF THE STUDY

The aim of this study was to identify the active components of HLJDD that could promote angiogenesis and investigate its underlying mechanism, as well as Hypoxia-inducible factor-1α (HIF-1α)/Vascular endothelial growth factor (VEGF) signalings in human umbilical vein endothelial cells (HUVECs).

MATERIALS AND METHODS

The specific binding components of HLJDD with HUVECs were isolated and identified through a combination of live cell biospecific extraction, solid-phase extraction, and ultra performance liquid chromatography (UPLC)-Orbitrap Fusion Tribrid mass spectrometry (MS). Their pharmacological activity against oxygen-glucose deprivation-reperfusion (OGD/R) injury and in vitro pro-angiogenesis was validated using Cell Counting Kit-8 (CCK-8) and tube formation analysis, respectively. Finally, we explored the effect of active ingredients on the expression levels of HIF-1α and VEGF using enzyme-linked immunosorbent assay. Molecular docking was used to predict the potential binding of six active components to phosphoinositide 3-kinase (PI3K), serine/threonine-specific protein kinase (AKT) and Von Hippel-Lindau (VHL) proteins, which are involved in the regulation of HIF-1α and are highly associated with angiogenesis.

RESULTS

A total of 13 HUVECs-specific HLJDD components were identified, and 10 of them were shown to protect against OGD/R injury. We were the first to demonstrate that two of these components have a protective role in OGD/R-induced HUVECs injury. Additionally, seven of these 10 components exhibited angiogenesis-promoting activity, and two of these components were shown, for the first time, to promote angiogenesis in HUVECs. These effects might occur through the HIF-1α/VEGF pathway. Molecular docking results showed that all six active ingredients could stably bind to PI3K and AKT proteins, suggesting that these two proteins may be potential targets for six active ingredients.

CONCLUSIONS

The approach employed in this study effectively identified proangiogenic components in HLJDD that might act via PI3K/AKT/HIF-1α/VEGF pathways and other mechanisms involved in angiogenesis. In conclusion, this study was the first to demonstrate four compounds with new bioactivities and could also provide insight into the isolation and discovery of new bioactive compounds existing in Chinese medicine with potential clinical value.

Supplementary Pharmacotherapy for the Behavioral Abnormalities Caused by Stressors in Humans, Focused on Post-Traumatic Stress Disorder (PTSD)

Used as a supplement to psychotherapy, pharmacotherapy that addresses all of the known metabolic and genetic contributions to the pathogenesis of psychiatric conditions caused by stressors would require an inordinate number of drugs. Far simpler is to address the abnormalities caused by those metabolic and genetic changes in the cell types of the brain that mediate the behavioral abnormality. Relevant data regarding the changed brain cell types are described in this article and are derived from subjects with the paradigmatic behavioral abnormality of PTSD and from subjects with traumatic brain injury or chronic traumatic encephalopathy. If this analysis is correct, then therapy is required that benefits all of the affected brain cell types; those are astrocytes, oligodendrocytes, synapses and neurons, endothelial cells, and microglia (the pro-inflammatory (M1) subtype requires switching to the anti-inflammatory (M2) subtype). Combinations are advocated using several drugs, erythropoietin, fluoxetine, lithium, and pioglitazone, that benefit all of the five cell types, and that should be used to form a two-drug combination, suggested as pioglitazone with either fluoxetine or lithium. Clemastine, fingolimod, and memantine benefit four of the cell types, and one chosen from those could be added to the two-drug combination to form a three-drug combination. Using low doses of chosen drugs will limit both toxicity and drug-drug interactions. A clinical trial is required to validate both the advocated concept and the choice of drugs.

Formulating treatment of major psychiatric disorders: algorithm targets the dominantly affected brain cell-types

BACKGROUND

Pharmacotherapy for most psychiatric conditions was developed from serendipitous observations of benefit from drugs prescribed for different reasons. An algorithmic approach to formulating pharmacotherapy is proposed, based upon which combination of changed activities by brain cell-types is dominant for any particular condition, because those cell-types contain and surrogate for genetic, metabolic and environmental information, that has affected their function. The algorithm performs because functions of some or all the affected cell-types benefit from several available drugs: clemastine, dantrolene, erythropoietin, fingolimod, fluoxetine, lithium, memantine, minocycline, pioglitazone, piracetam, and riluzole PROCEDURES/FINDINGS: Bipolar disorder, major depressive disorder, schizophrenia, Alzheimer's disease, and post-traumatic stress disorder, illustrate the algorithm; for them, literature reviews show that no single combination of altered cell-types accounts for all cases; but they identify, for each condition, which combination occurs most frequently, i.e., dominates, as compared with other possible combinations. Knowing the dominant combination of altered cell-types in a particular condition, permits formulation of therapy with combinations of drugs taken from the above list. The percentage of patients who might benefit from that therapy, depends upon the frequency with which the dominant combination occurs in patients with that particular condition.

CONCLUSIONS

Knowing the dominant combination of changed cell types in psychiatric conditions, permits an algorithmically formulated, rationally-based treatment. Different studies of the same condition often produce discrepant results; all might be correct, because identical clinical phenotypes result from different combinations of impaired cell-types, thus producing different results. Clinical trials would validate both the proposed concept and choice of drugs.

Changes in somatosensory evoked potentials in rats following transient cerebral ischemia

Background. Cerebral ischemia induced by transient middle cerebral artery occlusion is one of the most popular ischemic stroke models used to evaluate drug candidates with neuroprotective properties. The possibilities of combining this model with neurophysiological techniques (e.g., electroencephalography, electrocorticography, evoked potential registration, etc.) to assess the effectiveness of novel pharmacotherapeutic strategies appear to be of great interest to current biomedical research.

The aim. Identifying specific changes in somatosensory evoked potentials occurring after cerebral ischemia induced by middle cerebral artery occlusion in rats.

Materials and methods. A total number of 18 white outbred male rats were randomized into 3 groups by 6 animals in each: 1) control (presumably healthy animals); 2) ischemia-30 (30-minute middle cerebral artery occlusion); 3) ischemia-45 (45-minute occlusion). At post-surgery day 7, cortical responses to sequential electrical stimulation of left and right n. ischiadicus were registered. N1, P2, N2, P3, and N3 peak latencies and amplitudes, peak-to-peak interval durations and amplitudes were calculated. Spearman’s rank correlation coefficients were used to assess the relationship between ischemia duration and evoked potential parameters, and the Chaddock scale was used to qualitatively evaluate the strength of correlations.

Results. The rats subjected to cerebral ischemia demonstrated a decrease in some of the peak amplitudes of the ipsi- and contralateral somatosensory potentials evoked by n. ischiadicus stimulation. In the injured hemisphere, decreased P2 and N3 peak and P3–N3 interval amplitudes were registered ipsilaterally, and decreased P3 peak amplitudes and N2–P3 interval durations were observed contralaterally.

Conclusions. The obtained data suggest that somatosensory evoked potential registration and analysis can be used to evaluate the functional state of central nerve tracts in rats subjected to cerebral ischemia.

A Review of Neuroprotective Effects and Mechanisms of Ginsenosides From Panax Ginseng in Treating Ischemic Stroke

Ischemic stroke has been considered one of the leading causes of mortality and disability worldwide, associated with a series of complex pathophysiological processes. However, effective therapeutic methods for ischemic stroke are still limited. Panax ginseng, a valuable traditional Chinese medicine, has been long used in eastern countries for various diseases. Ginsenosides, the main active ingredient of Panax ginseng, has demonstrated neuroprotective effects on ischemic stroke injury during the last decade. In this article, we summarized the pathophysiology of ischemic stroke and reviewed the literature on ginsenosides studies in preclinical and clinical ischemic stroke. Available findings showed that both major ginsenosides and minor ginsenosides (such as Rg3, Rg5, and Rh2) has a potential neuroprotective effect, mainly through attenuating the excitotoxicity, Ca²⁺ overload, mitochondria dysfunction, blood-brain barrier (BBB) permeability, anti-inflammation, anti-oxidative, anti-apoptosis, anti-pyroptosis, anti-autophagy, improving angiogenesis, and neurogenesis. Therefore, this review brings a current understanding of the mechanisms of ginsenosides in the treatment of ischemic stroke. Further studies, especially in clinical trials, will be important to confirm the clinical value of ginseng and ginsenosides.

Biological Functions and Regulatory Mechanisms of Hypoxia-Inducible Factor-1α in Ischemic Stroke

Ischemic stroke is caused by insufficient cerebrovascular blood and oxygen supply. It is a major contributor to death or disability worldwide and has become a heavy societal and clinical burden. To date, effective treatments for ischemic stroke are limited, and innovative therapeutic methods are urgently needed. 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, including neuronal survival, neuroinflammation, angiogenesis, glucose metabolism, and blood brain barrier regulation. In addition, the spatiotemporal expression profile of HIF-1α in the brain shifts with the progression of ischemic stroke; this has led to contradictory findings regarding its function in previous studies. Therefore, unveiling the Janus face of HIF-1α and its target genes in different type of cells and exploring the role of HIF-1α in inflammatory responses after ischemia is of great importance for revealing the pathogenesis and identifying new therapeutic targets for ischemic stroke. Herein, we provide a succinct overview of the current approaches targeting HIF-1α and summarize novel findings concerning HIF-1α regulation in different types of cells within neurovascular units, including neurons, endothelial cells, astrocytes, and microglia, during the different stages of ischemic stroke. The current representative translational approaches focused on neuroprotection by targeting HIF-1α are also discussed.

HIF‑1α in cerebral ischemia (Review)

Cerebral ischemic injury may lead to a series of serious brain diseases, death or different degrees of disability. Hypoxia-inducible factor-1α (HIF-1α) is an oxygen-sensitive transcription factor, which mediates the adaptive metabolic response to hypoxia and serves a key role in cerebral ischemia. HIF-1α is the main molecule that responds to hypoxia. HIF-1α serves an important role in the development of cerebral ischemia by participating in numerous processes, including metabolism, proliferation and angiogenesis. The present review focuses on the endogenous protective mechanism of cerebral ischemia and elaborates on the role of HIF-1α in cerebral ischemia. In addition, it focuses on cerebral ischemia interventions that act on the HIF-1α target, including biological factors, non-coding RNA, hypoxic-ischemic preconditioning and drugs, and expands upon the measures to strengthen the endogenous compensatory response to support HIF-1α as a therapeutic target, thus providing novel suggestions for the treatment of cerebral ischemia.

Associations between increased circulating endothelial progenitor cell levels and anxiety/depressive severity, cognitive deficit and function disability among patients with major depressive disorder

The association of major depressive disorder (MDD) with cardiovascular diseases (CVDs) through endothelial dysfunction is bidirectional. Circulating endothelial progenitor cells (cEPCs), essential for endothelial repair and function, are associated with risks of various CVDs. Here, the relationship of cEPC counts with MDD and the related clinical presentations were investigated in 50 patients with MDD and 46 healthy controls. In patients with MDD, a battery of clinical domains was analysed: depressed mood with Hamilton Depression Rating Scale (HAMD) and Montgomery–Åsberg Depression Rating Scale (MADRS), anxiety with Hamilton Anxiety Rating Scale (HAMA), cognitive dysfunction and deficit with Digit Symbol Substitution Test (DSST) and Perceived Deficits Questionnaire-Depression (PDQ-D), somatic symptoms with Depressive and Somatic Symptom Scale (DSSS), quality of life with 12-Item Short Form Health Survey (SF-12) and functional disability with Sheehan Disability Scale (SDS). Immature and mature cEPC counts were measured through flow cytometry. Increased mature and immature cEPC counts were significantly associated with higher anxiety after controlling the confounding effect of systolic blood pressure, and potentially associated with more severe depressive symptoms, worse cognitive performance and increased cognitive deficit, higher social disability, and worse mental health outcomes. Thus, cEPCs might have pleiotropic effects on MDD-associated symptoms and psychosocial outcomes.

Vortioxetine mitigates neuronal damage by restricting PERK/eIF2α/ATF4/CHOP signaling pathway in rats subjected to focal cerebral ischemia-reperfusion

AIMS

Stroke has risen to the fifth and third most common causes of death in the United States and the rest of the world, respectively. Vortioxetine (VTX) is a multimodal antidepressant agent that balances 5-HT receptors and represses the serotonin transporter. Our study aimed to examine the neuroprotective impacts of VTX against cerebral ischemia caused by occluding the middle cerebral artery (MCA).

MAIN METHODS

Until the middle cerebral artery occlusion (MCAO) induction, VTX (10 mg/kg/day) was taken orally for 14 days. Behavioral assessments were carried out 24 h after the MCAO technique. The hippocampal and cortical tissues of the brain were isolated to assess the histological changes and the levels of the biochemical parameters.

KEY FINDINGS

MCAO damage led to severe neurological deficits and histopathological damage. However, VTX improved MCAO-induced neurological deficits and ameliorated histopathological changes in both hippocampal and cortical tissues of MCAO rats. Western blot analysis showed increments of p-PERK, CHOP, ASK-1, NICD, HES-1, HES-5, and p-eIF2α expression levels in MCAO rats. Moreover, ELISA revealed an increase in the levels of ATF4, IRE1, Apaf-1, and HIF-1α, while VTX administration ameliorated most of these perturbations induced after MCAO injury.

SIGNIFICANCE

This research suggests that VTX could be a potent neuroprotective agent against ischemic stroke by inhibiting a variety of oxidative, apoptotic, inflammatory, and endoplasmic reticulum stress pathways.

A neutrophil-mimetic magnetic nanoprobe for molecular magnetic resonance imaging of stroke-induced neuroinflammation

Neuroinflammation plays a key role in the progression of brain injury induced by stroke, and has become a promising target for therapeutic intervention for stroke. Monitoring this pivotal process of neuroinflammation is highly desirable to guide specific therapy. However, there is still a lack of a satisfactory nanoprobe to selectively monitor neuroinflammation. As endothelial cell activation is a hallmark of neuroinflammation, it would be clinically relevant to develop a non-invasive in vivo imaging technique to detect the endothelial activation process. Herein, inspired by the specific neutrophil-endothelium interaction, we designed neutrophil-camouflaged magnetic nanoprobes (NMNPs) that can be used to target activated endothelial cells for improved neuroinflammation imaging. NMNPs are composed of an inner core of superparamagnetic iron oxide (SPIO)-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles and a biomimetic outer shell of a neutrophil membrane, which maintained the biocompatibility and targeting ability of neutrophils and the excellent contrast effects of SPIO. Moreover, we demonstrated that NMNPs can successfully bind to inflamed cerebral vasculature using the intravital imaging of live cerebral microvessels in transient middle cerebral artery occlusion (tMCAO) mice. After that, NMNPs could further accumulate in the brain vasculature and exhibit excellent contrast effects for stroke-induced neuroinflammation and biosafety. We believe that the neutrophil-camouflaged magnetic nanoprobe could serve as a highly safe and selective nanoprobe for neuroinflammation imaging and has alluring prospects for clinical application.

XQ-1H promotes cerebral angiogenesis via activating PI3K/Akt/GSK3β/β-catenin/VEGF signal in mice exposed to cerebral ischemic injury

Stroke still ranks as a most lethal disease worldwide. Angiogenesis during the chronic phase of ischemic stroke can alleviate ischemic injury and attenuate neurological deficit. XQ-1H is a new compound derived from the structure modification of ginkgolide B, which exerts anti-inflammation and neuroprotection against cerebral ischemic injury during the acute or subacute phase. However, whether XQ-1H facilitates angiogenesis and neural functional recovery during the chronic phase remains unclear. This research was designed to explore whether XQ-1H promotes angiogenesis after ischemic stroke and to preliminarily elucidate the mechanism. In vitro, XQ-1H was found to facilitate proliferation, migration and tube formation in bEnd.3 cells. In vivo, XQ-1H raised the CD31 positive microvessel number and increased focal cerebral blood flow in mice exposed to cerebral ischemic injury, and improved the neurological function. Mechanism studies revealed that XQ-1H exerted angiogenesis promoting effect via the PI3K/Akt/GSK3β/β-catenin/VEGF signal pathway, which was reversed by LY294002 (the specific inhibitor of PI3K/Akt). In conclusion, XQ-1H exerts angiogenetic effect both in vivo and in vitro, which is a potential agent against ischemic stroke during chronic phase.

Delayed atomoxetine or fluoxetine treatment coupled with limited voluntary running promotes motor recovery in mice after ischemic stroke

Currently, there is an unmet need for treatments promoting post-stroke functional recovery. The aim of this study was to evaluate and compare the dose-dependent effect of delayed atomoxetine or fluoxetine therapy (starting on post-stroke day 5), coupled with limited physical exercise (2 hours daily voluntary wheel running; post-stroke days 9 to 42), on motor recovery of adult male mice after photothrombotic stroke. These drugs are selective norepinephrine or serotonin reuptake inhibitors indicated for disorders unrelated to stroke. The predetermined primary end-point for this study was motor function measured in two tasks of spontaneous motor behaviors in grid-walking and cylinder tests. Additionally, we quantified the running distance and speed throughout the study, the number of parvalbumin-positive neurons in the medial agranular cortex and infarct volumes. Both sensorimotor tests revealed that neither limited physical exercise nor a drug treatment alone significantly facilitated motor recovery in mice after stroke. However, combination of physical exercise with either of the drugs promoted restoration of motor function by day 42 post-stroke, with atomoxetine being a more potent drug. This was accompanied by a significant decrease in parvalbumin-positive inhibitory interneurons in the ipsilateral medial agranular cortex of mice with recovering motor function, while infarct volumes were comparable among experimental groups. If further validated in larger studies, our observations suggest that add-on atomoxetine or fluoxetine therapy coupled with limited, structured physical rehabilitation could offer therapeutic modality for stroke survivors who have difficulty to engage in early, high-intensity physiotherapy. Furthermore, in light of the recently completed Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) and Efficacy oF Fluoxetine-a randomisEd Controlled Trial in Stroke (EFFECTS) trials, our observations call for newly designed studies where fluoxetine or atomoxetine pharmacotherapy is evaluated in combination with structured physical rehabilitation rather than alone. This study was approved by the Texas Tech University Health Sciences Center Institutional Animal Care and Use Committee (protocol # 16019).

A Systematic Study of Mechanism of Sargentodoxa cuneata and Patrinia scabiosifolia Against Pelvic Inflammatory Disease With Dampness-Heat Stasis Syndrome via Network Pharmacology Approach

Objective: To investigate the mechanism of Sargentodoxa cuneata (Oliv.) Rehder & E.H.Wilson (SC) and Patrinia scabiosifolia (PS) against Pelvic Inflammatory Disease with Dampness-Heat Stasis Syndrome via network pharmacological approach and experimental validation.

Methods: The active compounds with OB ≥ 30% and DL ≥ 0.18 were obtained from TCMSP database and further confirmed by literature research. The targets of the compounds and disease were acquired from multiple databases, such as GeneCards, CTD and TCMSP database. The intersection targets were identified by Venny software. Cytoscape 3.7.0 was employed to construct the protein-protein interaction (PPI) network and compound-target network. Moreover, GO enrichment and KEGG pathway analysis were analyzed by DAVID database. Finally, CCK-8, Griess assay and a cytometric bead array (CBA) immunoassay were used for experimental validation by detecting the influence of the active compounds on proliferation of macrophage, release of NO and TNF-α after LPS treatment.

Results: 9 bioactive compounds were identified from SC and PS. Those compounds corresponded to 134 targets of pelvic inflammatory disease with dampness-heat stasis syndrome. The targets include vascular endothelial growth factor A (VEGFA), von willebrand factor (VWF), interleukin 6 (IL6), tumor necrosis factor (TNF) and nuclear transcription factor 1 (NFκB1). They act on the signaling pathways like advanced glycation end products-receptor of advanced glycation end products (AGE-RAGE), focal adhesion (FA), Toll-like receptor (TLR) and nuclear transcription factor κB (NF-κB). In addition, by in vitro validation, the selected active components of SC and PS such as acacetin, kaempferol, linarin, isovitexin, sinoacutine could significantly inhibit the release of NO induced by LPS, respectively. Moreover, different dose of acacetin, kaempferol, isovitexin and sinoacutine significantly inhibits the TNF-α production.

Conclusion: This study provides solid evidence for the anti-inflammatory mechanism of SC and PS against pelvic inflammatory disease with dampness-heat stasis syndrome, which will provide a preliminary evidence and novelty ideas for future research on the two herbs.

Decreased serum netrin-1 is associated with ischemic stroke: A case-control study

BACKGROUND AND AIMS

Netrin-1 was a laminin-related protein involved in neurovascular protection, and we previously discovered that decreased serum netrin-1 was associated with poor prognosis of ischemic stroke. However, the relationship between serum netrin-1 level and the risk of ischemic stroke remains unclear. The aim of this study was to investigate the association between netrin-1 level and risk of ischemic stroke.

METHODS AND RESULTS

A case-control study including 591 ischemic stroke patients and 591 age- and sex-matched healthy individuals was conducted, and serum netrin-1 concentrations were quantitatively determined via enzyme-linked immunosorbent assay for all participants. The serum netrin-1 levels were significantly lower in the ischemic stroke patients than those in matched controls (median, 496.4 vs 652.1 pg/mL; P < 0.001). After adjustment for potential confounders, the odds ratio of ischemic stroke associated with the highest quartile of netrin-1 was 0.07 (95% CI: 0.01-0.65; P_trend = 0.018) compared with the lowest quartile of netrin-1. Each 1-standard deviation increase of log-transformed netrin-1 was associated with a lower odds of ischemic stroke (odds ratio: 0.45, 95% CI: 0.22-0.94; P = 0.032), and a dose-response relationship between serum netrin-1 and ischemic stroke was observed (P_linearity = 0.003). Incorporating netrin-1 to conventional risk factors improved the discriminatory power for ischemic stroke (net reclassification index = 98.0%, P < 0.001; integrated discrimination improvement = 0.28%, P = 0.027).

CONCLUSIONS

Serum netrin-1 was decreased in patients with ischemic stroke compared with healthy controls, suggesting that there was a potential role of netrin-1 in the pathogenesis of ischemic stroke.

Analysis of Antiapoptosis Effect of Netrin-1 on Ischemic Stroke and Its Molecular Mechanism under Deleted in Colon Cancer/Extracellular Signal-Regulated Kinase Signaling Pathway

To analyze the regulatory effect of Netrin-1 in ischemic stroke and its influence on Deleted in Colon Cancer (DCC)/Extracellular Signal-regulated Kinase (ERK) signaling pathway, 20 male rats were selected to construct the rat model of middle cerebral artery occlusion (MCAO), 10 normal rats were selected as healthy controls (Normal Saline (NS)), and they were divided into the MCAO+Netrin-1 group, MCAO group, and NS group according to different treatment schemes. The positive expression of Netrin-1 was detected by immunostaining, magnetic resonance imaging (MRI) was adopted to detect the percentage of rat cerebral infarct volume in the cerebral hemispheres, and Modified Neurological Severity Score (mNSS) was adopted to evaluate postoperative neurological function in rats. Besides, a tunnel staining experiment was applied to detect the apoptosis rate of rat neurons, the sticker removal test was applied to evaluate the postoperative sensory function of rats, and fluorescence staining was adopted to detect the expression of DCC and ERK in rats. The results showed that the percentage of cerebral infarction volume in the cerebral hemispheres of the MCAO+Netrin-1 group was higher than that of the MCAO and NS groups (P < 0.05); in the MCAO+Netrin-1 group, the MCAO mNSS scoring and the time spent in the sticker removal test were lower than the MCAO group (P < 0.05); the apoptosis rate of rats in the MCAO+Netrin-1 group was lower than that in the MCAO group (P < 0.05); the average fluorescence intensity of DCC and p-ERK in the MCAO+Netrin-1 group was higher than that in the MCAO group (P < 0.05); the average fluorescence intensity of p-ERK in the MCAO+Netrin-1 group was higher than that in the MCAO group (P < 0.05). In short, Netrin-1 can effectively reduce the brain tissue damage in rats with ischemic stroke, improve the nerve function and sensory function of rats, and inhibit neuronal cell apoptosis. Netrin-1 can promote DCC expression and ERK phosphorylation, and the EPK signaling pathway may be involved in the antiapoptotic effect of Netrin-1.

An Enriched Environment Enhances Angiogenesis Surrounding the Cingulum in Ischaemic Stroke Rats

An enriched environment (EE) has been demonstrated to improve functional recovery in animal models of ischaemic stroke through enhancing vascular endothelial growth factor- (VEGF-) mediated neuroprotection accompanied by angiogenesis in the ischaemic hemisphere. Whether EEs also promote VEGF-mediated neuroprotection and angiogenesis in the contralateral hemisphere remains unclear. Here, we explored the effect of EEs on VEGF expression and angiogenesis within the contralateral cerebral cortex in a rat middle cerebral artery occlusion/reperfusion (MCAO/r) model. We assessed the expression levels of platelet endothelial cell adhesion molecule-1 (CD31), VEGF, and endothelial nitric oxide synthase (eNOS) in the whole contralateral cerebral cortex using Western blotting assay but did not find an increase in the expression of CD31, VEGF, or eNOS in MCAO/r rats housed in EEs, which suggested that EEs did not enhance the overall expression of VEGF and eNOS or angiogenesis in the entire contralateral cortex. We further analysed the local effect of EEs by immunohistochemistry and found that in and around the bilateral cingulum in MCAO/r rats housed in EEs, haematopoietic progenitor cell antigen- (CD34-) positive endothelial progenitor cells were significantly increased compared with those of rats housed in standard cages (SCs). Further experiments showed that EEs increased neuronal VEGF expression surrounding the cingulum in MCAO/r rats and robustly upregulated eNOS expression. These results revealed that EEs enhanced angiogenesis, VEGF expression, and activation of the VEGF-eNOS pathway in and/or around the cingulum in MCAO/r rats, which were involved in the functional recovery of MCAO/r rats.