Morin Attenuated Cerebral Ischemia/Reperfusion Injury Through Promoting Angiogenesis Mediated by Angiopoietin-1-Tie-2 Axis and Wnt/β-Catenin Pathway

Hirudin promotes cerebral angiogenesis and exerts neuroprotective effects in MCAO/R rats by activating the Wnt/β-catenin pathway

OBJECTIVE

Hirudin has shown potential in promoting angiogenesis and providing neuroprotection in ischemic stroke; however, its therapeutic role in promoting cerebrovascular angiogenesis remains unclear. In this study, we aimed to investigate whether hirudin exerts neuroprotective effects by promoting angiogenesis through the regulation of the Wnt/β-catenin signaling pathway.

METHODS

An in vitro model of glucose and oxygen deprivation/reperfusion (OGD/R) was established using rat brain microvascular endothelial cells (BMECs). The effects of hirudin on OGD/R cell viability were assessed using the cell counting kit-8 (CCK-8) assay. The angiogenic potential of hirudin was evaluated using Transwell and tube formation assays. In vivo, a middle cerebral artery occlusion/reperfusion (MCAO/R) model was created in rats. The neuroprotective effects of hirudin were assessed using the modified neurological severity score (mNSS), Hematoxylin and eosin (H&E) staining, 2,3,5-Triphenyltetrazolium chloride (TTC) staining, and immunofluorescence staining. Dickkopf-1 (DKK1), a specific inhibitor of this pathway, was introduced in order to investigate the role of the Wnt/β-catenin pathway. The effects of hirudin on the Wnt/β-catenin pathway were examined through immunohistochemistry, western blotting, and reverse transcription quantitative polymerase chain reaction (RT-qPCR).

RESULTS

Hirudin significantly improved BMEC survival and enhanced both cell migration and tube formation in the OGD/R model. In the MCAO/R model, hirudin reduced the mNSS score, alleviated pathological damage, decreased infarction volume, and increased the expression of key angiogenic factors, including CD34, vascular endothelial growth factor (VEGF), and angiopoietin-2 (Ang-2). In addition, hirudin activated the Wnt/β-catenin pathway, leading to elevated levels of Wnt3a and β-catenin.

CONCLUSION

Hirudin has substantial neuroprotective effects associated with the promotion of angiogenesis in the ischemic penumbra. This mechanism is mediated by the regulation of the Wnt/β-catenin pathway.

Polyphenols as Wnt/β-catenin pathway modulators: A promising strategy in clinical neurodegeneration

Polyphenols, a diverse group of naturally occurring compounds found in plants, have garnered significant attention for their potential therapeutic properties in treating neurodegenerative diseases (NDs). The Wnt/β-catenin (WβC) signaling pathway, a crucial player in neurogenesis, neuronal survival, and synaptic plasticity, is involved in several cellular mechanisms related to NDs. Dysregulation of this pathway is a hallmark in the development of various NDs. This study explores multiple polyphenolic compounds, such as flavonoids, stilbenes, lignans, and phenolic acids, and their potential to protect the nervous system. It provides a comprehensive analysis of their effects on the WβC pathway, elucidating their modes of action. The study highlights the dual function of polyphenols in regulating and protecting the nervous system, providing reassurance about the research benefits. This review provides a comprehensive analysis of the results obtained from both in vitro studies and in vivo research, shedding light on how these substances influence the various components of the pathway. The focus is mainly on the molecular mechanisms that allow polyphenols to reduce oxidative stress, inflammation, and apoptotic processes, ultimately improving the function and survival of neurons. This study aims to offer a thorough understanding of the potential of polyphenols in targeting the WβC signaling pathway, which could lead to the development of innovative therapeutic options for NDs.

Bioinformatics Identification of angiogenesis-related biomarkers and therapeutic targets in cerebral ischemia-reperfusion

Promoting vascular endothelial cell regeneration can enhance recovery from cerebral ischemia reperfusion injury (CIRI), but there is a lack of bioinformatic studies on angiogenesis-related biomarkers in CIRI. In this study, we utilized the GSE97537 and GSE61616 datasets from GEO to identify 181 angiogenesis-related genes (ARGs) and analyzed differentially expressed genes (DEGs) between CIRI and control groups. We converted ARGs to 169 rat homologues and intersected them with DEGs to find DE-ARGs. RF and XGBoost models were employed to identify five biomarkers (Stat3, Hmox1, Egfr, Col18a1, Ptgs2) and conducted GSEA on these biomarkers, revealing their enrichment in pathways such as ECM-receptor interaction and hematopoietic cell lineage. We also analyzed the immune microenvironment, finding significant differences in 21 immune cells between CIRI and control groups. Furthermore, we constructed lncRNA-miRNA-mRNA networks and drug-gene networks. Finally, biomarker expression was compared between the CIRI and control groups by qRT-PCR in tissue and blood samples. Overall, our bioinformatic exploration of angiogenesis-related biomarkers in CIRI provides new insights for the diagnosis and treatment of CIRI.

The Effect of Conditioned Medium from Angiopoietin-1 Gene-Modified Mesenchymal Stem Cells on Wound Healing in a Diabetic Mouse Model

INTRODUCTION

Mesenchymal stem cells (MSCs) have been introduced as a promising treatment for diabetic wounds. The effects of stem cell therapy are thought to be caused by bioactive molecules secreted by stem cells. Stem cell-based gene therapies can target bioactive molecules. Therefore, treatment using conditioned medium (CM) derived from genetically engineered stem cells has been proposed as an alternative option for diabetic ulcer care.

METHODS

MSCs derived from human umbilical cords were obtained and engineered to overexpress the angiogenin-1 gene (MSCsAng1) through plasmid transfection. This study extracted conditioned medium from MSCs (MSC-CM) or MSCsAng1(MSCAng1-CM) for wound treatment applications. Via in vitro experiments, the proangiogenic effects of MSCAng1-CM were assessed via the migration and tube formation of human umbilical vein endothelial cells (HUVECs). Furthermore, the efficacy of MSCAng1-CM in promoting wound healing, re-epithelialization, hair follicle, and angiogenesis was evaluated via a diabetic mouse skin defect model.

RESULTS

In vitro assays demonstrated that MSCAng1-CM significantly enhanced HUVECs' functions, including migration and tube formation. In vivo assays revealed that MSCAng1-CM exhibited notable advancements in healing speed, re-epithelialization, hair follicle, and angiogenesis.

CONCLUSION

These results indicate that MSCAng1-CM can promote wound healing in diabetic mice and make the vascular structure in regenerated tissues more stable without inducing tissue fibrosis, providing a new therapeutic strategy for treating diabetic skin wounds. This provides a valuable theoretical basis for further research on regenerative medicine and cell therapy.

Endothelial Dysfunctions in Blood-Brain Barrier Breakdown in Alzheimer's Disease: From Mechanisms to Potential Therapies

Recent research has shown the presence of blood-brain barrier (BBB) breakdown in Alzheimer's disease (AD). BBB is a dynamic interface consisting of a continuous monolayer of brain endothelial cells (BECs) enveloped by pericytes and astrocytes. The restricted permeability of BBB strictly controls the exchange of substances between blood and brain parenchyma, which is crucial for brain homeostasis by excluding blood-derived detrimental factors and pumping out brain-derived toxic molecules. BBB breakdown in AD is featured as a series of BEC pathologies such as increased paracellular permeability, abnormal levels and functions of transporters, and inflammatory or oxidative profile, which may disturb the substance transportation across BBB, thereafter induce CNS disorders such as hypometabolism, Aβ accumulation, and neuroinflammation, eventually aggravate cognitive decline. Therefore, it seems important to protect BEC properties for BBB maintenance and neuroprotection. In this review, we thoroughly summarized the pathological alterations of BEC properties reported in AD patients and numerous AD models, including paracellular permeability, influx and efflux transporters, and inflammatory and oxidative profiles, and probably associated underlying mechanisms. Then we reviewed current therapeutic agents that are effective in ameliorating a series of BEC pathologies, and ultimately protecting BBB integrity and cognitive functions. Regarding the current drug development for AD proceeds extremely hard, this review aims to discuss the therapeutic potentials of targeting BEC pathologies and BBB maintenance for AD treatment, therefore expecting to shed a light on the future AD drug development by targeting BEC pathologies and BBB protection.

Morin attenuated the global cerebral ischemia via antioxidant, anti-inflammatory, and antiapoptotic mechanisms in rats

Global cerebral ischemia is one of the major causes of memory and cognitive impairment. Hyperactivation of acetylcholine esterase (AChE), oxidative stress, and inflammation are reported to cause memory and cognitive impairment in global cerebral ischemia. Morin, a flavonoid, is reported to have neuroprotective properties through its antioxidant and anti-inflammatory in multiple neurological diseases. However, its neuroprotective effects and memory and cognition enhancement have not yet been investigated. In the present study, we have determined the memory and cognition, and neuroprotective activity of Morin in bilateral common carotid artery occlusion and reperfusion (BCCAO/R) in Wistar rats. We found that Morin treatment significantly improved motor performance like grip strength and rotarod. Further, Morin improved memory and cognition in BCCAO rats by decreasing the AchE enzyme activity and enhancing the acetylcholine (Ach) levels. Additionally, Morin exhibited neuroprotection by ameliorating oxidative stress, neuroinflammation, and apoptosis in BCCAO rats. These findings confirm that Morin could enhance memory and cognition by ameliorating AchE activity, oxidative stress, neuroinflammation, and apoptosis in global cerebral ischemia. Therefore, Morin could be a promising neuroprotective and memory enhancer against global cerebral ischemic injury.

Therapeutic Potential of Natural Compounds from Herbs and Nutraceuticals in Alleviating Neurological Disorders: Targeting the Wnt Signaling Pathway

As an important signaling pathway in multicellular eukaryotes, the Wnt signaling pathway participates in a variety of physiological processes. Recent studies have confirmed that the Wnt signaling pathway plays an important role in neurological disorders such as stroke, Alzheimer's disease, and Parkinson's disease. The regulation of Wnt signaling by natural compounds in herbal medicines and nutraceuticals has emerged as a potential strategy for the development of new drugs for neurological disorders. Purpose: The aim of this review is to evaluate the latest research results on the efficacy of natural compounds derived from herbs and nutraceuticals in the prevention and treatment of neurological disorders by regulating the Wnt pathway in vivo and in vitro. A manual and electronic search was performed for English articles available from PubMed, Web of Science, and ScienceDirect from the January 2010 to February 2023. Keywords used for the search engines were "natural products,″ "plant derived products,″ "Wnt+ clinical trials,″ and "Wnt+,″ and/or paired with "natural products″/″plant derived products", and "neurological disorders." A total of 22 articles were enrolled in this review, and a variety of natural compounds from herbal medicine and nutritional foods have been shown to exert therapeutic effects on neurological disorders through the Wnt pathway, including curcumin, resveratrol, and querctrin, etc. These natural products possess antioxidant, anti-inflammatory, and angiogenic properties, confer neurovascular unit and blood-brain barrier integrity protection, and affect neural stem cell differentiation, synaptic formation, and neurogenesis, to play a therapeutic role in neurological disorders. In various in vivo and in vitro studies and clinical trials, these natural compounds have been shown to be safe and tolerable with few adverse effects. Natural compounds may serve a therapeutic role in neurological disorders by regulating the Wnt pathway. This summary of the research progress of natural compounds targeting the Wnt pathway may provide new insights for the treatment of neurological disorders and potential targets for the development of new drugs.

Recent advances in tissue repair of the blood-brain barrier after stroke

The selective permeability of the blood-brain barrier (BBB) enables the necessary exchange of substances between the brain parenchyma and circulating blood and is important for the normal functioning of the central nervous system. Ischemic stroke inflicts damage upon the BBB, triggering adverse stroke outcomes such as cerebral edema, hemorrhagic transformation, and aggravated neuroinflammation. Therefore, effective repair of the damaged BBB after stroke and neovascularization that allows for the unique selective transfer of substances from the BBB after stroke is necessary and important for the recovery of brain function. This review focuses on four important therapies that have effects of BBB tissue repair after stroke in the last seven years. Most of these new therapies show increased expression of BBB tight-junction proteins, and some show beneficial results in terms of enhanced pericyte coverage at the injured vessels. This review also briefly outlines three effective classes of approaches and their mechanisms for promoting neoangiogenesis following a stroke.

Astragaloside IV promotes angiogenesis by targeting SIRT7/VEGFA signaling pathway to improve brain injury after cerebral infarction in rats

Cerebral infarction (CI) has become one of the leading causes of death and acquired disability worldwide. Astragaloside IV (AST IV), one of the basic components of Astragalus membranaceus, has a protective effect on CI. However, the underlying mechanism has not been conclusively elucidated. Therefore, this study aims to explore the underlying mechanism of AST IV improving brain injury after CI. Middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation/reoxygenation (OGD/R) were used to simulate cerebral infarction injury in SD rats and HUVECs cells. Neurologic score, Evans blue, TTC and HE staining were used to observe brain injury in rats. Cell viability and migration were measured in vitro. Angiogenesis was detected by immunofluorescence and tube formation assay, and cell cycle was detected by flow cytometry. Western blot was used to find the expression of related proteins. Molecular docking, virtual mutation, site-directed mutagenesis, MST, and lentivirus silencing were used for target validation. The results showed that AST IV alleviated neurological impairment and promoted angiogenesis after CI. Moreover, AST IV greatly increased the transcription levels of SIRT6 and SIRT7, but had no effect on SIRT1-SIRT5, and promoted cell viability, migration, angiogenesis and S phase ratio in OGD/R-induced HUVECs. Furthermore, AST IV up-regulated the protein expressions of CDK4, cyclin D1, VEGFA and VEGF2R. Interestingly, AST IV not only bound to SIRT7, but also increased the expression of SIRT7. Silencing SIRT7 by lentivirus neutralizes the positive effects of AST IV. Taken together, the present study revealed that AST IV may improve brain tissue damage after CI by targeting SIRT7/VEGFA signaling pathway to promote angiogenesis.

Acute aflatoxin B1-induced hepatic and cardiac oxidative damage in rats: Ameliorative effects of morin

Aflatoxins (AFs) are secondary metabolites produced by the fungus Aspergillus flavus, of which Aflatoxin-B1 (AFB1) appears to be the most cancerogenic and of the highest toxicity. AFB1 causes serious effects on several organs including the liver. Morin is a flavonol that exists in many fruits and plants and has diverse biological properties including anticancer, anti-atherosclerotic, antioxidant, anti-inflammatory, immunomodulatory, and multi-organ protective activities. The present study aims to evaluate the potential protective effects of morin against acute AFB1-induced hepatic and cardiac toxicity in rats. Forty rats were divided into five groups (n = 8) as follows: control received the vehicle, morin was orally administered 30/mg/kg body weight (MRN30), the AFB1 was administered orally at a dose of 2.5 mg/kg, twice on days 12 and 14 of the experiment for the 3rd, 4th, and 5th groups., AFB1-MRN15 was orally given morin at a dose of 15 mg/kg body weight, and AFB1-MRN30 orally received morin at 30 mg/kg body weight. The results indicated a significant decrease in serum AST, ALP, LDH, GGT, CK, CK-MB, 8-OHdG, IL-1β, IL-6, TNF-a levels in MRN30 compared to AFB1, and AFB1-MRN15 groups. However, the results indicated non-significant differences in the serum levels between MRN30, control, and AFB1-MRN30 groups. Meanwhile, regarding the hepatic and cardiac parameters, there were significant differences in the levels of MDA, NO, GSH, GSH-Px, SOD, and CAT in MRN30 compared to AFB1, and AFB1-MRN15 groups, overall implying the protective effects of morin. To conclude, morin at a dose of 30 mg/kg b. wt. showed significant enhancements in acute AFB1-induced hepatic and cardiac toxicity in rats, which could play a role in limiting the public health hazards of AFs.

PFT-α protects the blood-brain barrier through the Wnt/β-catenin pathway after acute ischemic stroke

The dysfunction of blood-brain barrier (BBB) plays a pivotal role in brain injury and subsequent neurological deficits of ischemic stroke. The current study aimed to examine the potential correlation between p53 inhibition and the neuroprotective effect of on the BBB. Rat middle cerebral artery occlusion and reperfusion model (MCAO/R) and oxygen-glucose deprivation/re-oxygenation model (OGD/R) were employed to simulate cerebral ischemia-reperfusion (CI/R) injury occurrence in vivo and in vitro. mNSS and TTC staining were applied to evaluate neurological deficits and brain infarct volumes. Evans blue (EB) staining was carried out to examine the permeability of BBB. RT-qPCR and Western blot to examine the mRNA and protein levels. Cell viabilities were detected by CCK-8. Flow cytometry and ELISA assay were employed to examine apoptosis and neuroinflammation levels. TEER value and sodium fluorescein were carried out to explore the permeability of HBMEC cells. PFT-α inhibited P53 and promoted the expression of β-catenin and cyclin D1, which were reversed by DKK1. PFT-α inhibited neurological deficits, brain infarct volume, neuroinflammation, apoptosis, and BBB integrity than the MCAO/R rats; however, this inhibition was reversed by DKK1. PFT-α promoted OGD/R-induced cell viability in NSCs, and suppressed inflammation and apoptosis, but DKK1 weakened the effect of PFT-α. PFT-α increased OGD/R-induced TEER values in cerebrovascular endothelial cells, inhibited sodium fluorescein permeability, and increased the mRNA levels of tight junction protein, but they were all attenuated by DKK1. PFT-α protects the BBB after acute ischemic stroke via the Wnt/β-catenin pathway, which in turn improves neurological function.

Elabela-APJ axis mediates angiogenesis via YAP/TAZ pathway in cerebral ischemia/reperfusion injury

Angiogenesis helps to improve neurological recovery by repairing damaged brain tissue and restoring cerebral blood flow (CBF). The role of the Elabela (ELA)-Apelin receptor (APJ) system in angiogenesis has gained much attention. We aimed to investigate the function of endothelial ELA on postischemic cerebral angiogenesis. Here, we demonstrated that the endothelial ELA expression was upregulated in the ischemic brain and treatment with ELA-32 mitigated brain injury and enhanced the restoration of CBF and newly formed functional vessels following cerebral ischemia/reperfusion (I/R) injury. Furthermore, ELA-32 incubation potentiated proliferation, migration, and tube formation abilities of the mouse brain endothelial cells (bEnd.3 cells) under oxygen-glucose deprivation/reoxygenation (OGD/R) condition. RNA sequencing analysis indicated that ELA-32 incubation had a role in the Hippo signaling pathway, and improved angiogenesis-related gene expression in OGD/R-exposed bEnd.3 cells. Mechanistically, we depicted that ELA could bind to APJ and subsequently activate YAP/TAZ signaling pathway. Silence of APJ or pharmacological blockade of YAP abolished the pro-angiogenesis effects of ELA-32. Together, these findings highlight the ELA-APJ axis as a potential therapeutic strategy for ischemic stroke by showing how activation of this pathway promotes poststroke angiogenesis.

Targeting Non-Coding RNA for CNS Injuries: Regulation of Blood-Brain Barrier Functions

Central nervous system (CNS) injuries are the most common cause of death and disability around the world. The blood-brain barrier (BBB) is located at the interface between the CNS and the surrounding environment, which protects the CNS from exogenous molecules, harmful agents or microorganisms in the blood. The disruption of BBB is a common feature of CNS injuries and participates in the pathological processes of secondary brain damage. Recently, a growing number of studies have indicated that non-coding RNAs (ncRNAs) play an important role in brain development and are involved in CNS injuries. In this review, we summarize the mechanisms of BBB breakdown after CNS injuries. We also discuss the effects of ncRNAs including long noncoding RNAs (lncRNAs), circular RNAs (circRNAs) and microRNAs (miRNAs) on BBB damage in CNS injuries such as ischemic stroke, traumatic brain injury (TBI), intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH). In addition, we clarify the pharmacotherapies that could regulate BBB function via ncRNAs in CNS injuries, as well as the challenges and perspectives of ncRNAs on modulation of BBB function. Hence, on the basis of these effects, ncRNAs may be developed as therapeutic agents to protect the BBB for CNS injury patients.