Therapeutic effect of Ginkgo biloba polysaccharide in rats with focal cerebral ischemia/reperfusion (I/R) injury

Type-1 diabetes: Lessons from a decade of preclinical studies on phytotherapy

BACKGROUND

In recent decades, numerous herbal products have been shown to have antihyperglycemic and beta cell-regenerative effects in animal studies. However, there is no clinical evidence that those products completely cure patients with type-1 diabetes (T1D). Therefore, it seems that most of the phytochemicals do not have a significant impact on human beta cells, and the results of experimental studies conducted on them may not be generalizable to the clinic.

PURPOSE

The present work aims to review extensively the methods and results of preclinical studies on phytotherapy of T1D published in the last 10 years.

METHODS

This paper critically analyzes the designs of studies, treatment protocols, methods of diabetes induction, characteristics of the studied animals, clinical relevance, reproducibility of research, and other aspects related to conducting preclinical studies on T1D. We discussed limitations that make many of the results of these studies not generalizable to the clinic. Finally, some recommendations were given to improve studies on the phytotherapy of T1D to avoid misleading interpretations about the antidiabetic effect of herbal compounds.

CONCLUSION

This paper can be considered a practical guide for researchers interested in the field of phytotherapy of T1D to increase the reliability, reproducibility, and validity of their preclinical studies.

Neurovascular coupling impairment as a mechanism for cognitive deficits in COVID-19

Components that comprise our brain parenchymal and cerebrovascular structures provide a homeostatic environment for proper neuronal function to ensure normal cognition. Cerebral insults (e.g. ischaemia, microbleeds and infection) alter cellular structures and physiologic processes within the neurovascular unit and contribute to cognitive dysfunction. COVID-19 has posed significant complications during acute and convalescent stages in multiple organ systems, including the brain. Cognitive impairment is a prevalent complication in COVID-19 patients, irrespective of severity of acute SARS-CoV-2 infection. Moreover, overwhelming evidence from in vitro, preclinical and clinical studies has reported SARS-CoV-2-induced pathologies in components of the neurovascular unit that are associated with cognitive impairment. Neurovascular unit disruption alters the neurovascular coupling response, a critical mechanism that regulates cerebromicrovascular blood flow to meet the energetic demands of locally active neurons. Normal cognitive processing is achieved through the neurovascular coupling response and involves the coordinated action of brain parenchymal cells (i.e. neurons and glia) and cerebrovascular cell types (i.e. endothelia, smooth muscle cells and pericytes). However, current work on COVID-19-induced cognitive impairment has yet to investigate disruption of neurovascular coupling as a causal factor. Hence, in this review, we aim to describe SARS-CoV-2's effects on the neurovascular unit and how they can impact neurovascular coupling and contribute to cognitive decline in acute and convalescent stages of the disease. Additionally, we explore potential therapeutic interventions to mitigate COVID-19-induced cognitive impairment. Given the great impact of cognitive impairment associated with COVID-19 on both individuals and public health, the necessity for a coordinated effort from fundamental scientific research to clinical application becomes imperative. This integrated endeavour is crucial for mitigating the cognitive deficits induced by COVID-19 and its subsequent burden in this especially vulnerable population.

Tangeretin Attenuates Cerebral Ischemia-Reperfusion-Induced Neuronal Pyroptosis by Inhibiting AIM2 Inflammasome Activation via Regulating NRF2

Pyroptosis is closely involved in the pathopoiesis of cerebral ischemia and reperfusion (I/R) injury which seriously dangers human's life. Studies report that tangeretin (TANG), which is enriched in the peel of Citrus reticulata, has neuroprotective effects. Here, we explored whether absent in melanoma 2 (AIM2) inflammasome-mediated pyroptosis is involved in the cerebral I/R injury and the protective mechanism of TANG against cerebral I/R injury. In this study, we found that TANG treatment effectively alleviated I/R-induced brain injury and inhibited neuronal pyroptosis in an in vivo mice model with middle cerebral artery occlusion/reperfusion (MCAO/R) injury and in an in vitro hippocampal HT22 cell model with oxygen-glucose deprivation and reoxygenation (OGD/R) injury. Furthermore, we found TANG inhibited cerebral I/R-induced neuronal AIM2 inflammasome activation in vivo and in vitro via regulating nuclear factor E2-related factor 2 (NRF2). Moreover, administration of ML385, a chemical inhibitor of NRF2, notably blocked the neuroprotective effects of TANG against cerebral I/R injury. In conclusion, TANG attenuates cerebral I/R-induced neuronal pyroptosis by inhibiting AIM2 inflammasome activation via regulating NRF2. These findings indicate TANG is a potential therapeutic agent for cerebral I/R injury.

Unveiling the neuroprotective potential of dietary polysaccharides: a systematic review

Central nervous system (CNS) disorders present a growing and costly global health challenge, accounting for over 11% of the diseases burden in high-income countries. Despite current treatments, patients often experience persistent symptoms that significantly affect their quality of life. Dietary polysaccharides have garnered attention for their potential as interventions for CNS disorders due to their diverse mechanisms of action, including antioxidant, anti-inflammatory, and neuroprotective effects. Through an analysis of research articles published between January 5, 2013 and August 30, 2023, encompassing the intervention effects of dietary polysaccharides on Alzheimer's disease, Parkinson's disease, depression, anxiety disorders, autism spectrum disorder, epilepsy, and stroke, we have conducted a comprehensive review with the aim of elucidating the role and mechanisms of dietary polysaccharides in various CNS diseases, spanning neurodegenerative, psychiatric, neurodevelopmental disorders, and neurological dysfunctions. At least four categories of mechanistic bases are included in the dietary polysaccharides' intervention against CNS disease, which involves oxidative stress reduction, neuronal production, metabolic regulation, and gut barrier integrity. Notably, the ability of dietary polysaccharides to resist oxidation and modulate gut microbiota not only helps to curb the development of these diseases at an early stage, but also holds promise for the development of novel therapeutic agents for CNS diseases. In conclusion, this comprehensive review strives to advance therapeutic strategies for CNS disorders by elucidating the potential of dietary polysaccharides and advocating interdisciplinary collaboration to propel further research in this realm.

Sodium Metabisulfite-Induced Hematotoxicity, Oxidative Stress, and Organ Damage Ameliorated by Standardized Ginkgo biloba in Mice

Sodium metabisulfite (SMB) is a biocide and antioxidant agent generally used as a preservative in food and beverage industries but can oxidize to harmful sulfite radicals. A standardized Ginkgo biloba (EGb-761) has demonstrated potent antioxidant and anti-inflammatory activities, which is beneficial for the treatment of diseases that exhibit oxidative stress and inflammation. The present study sought to investigate the putative ameliorative effects of EGb-761 against SMB-induced toxicity in mice. Thirty-two male Swiss white mice were randomized into control, SMB-treated, SMB + EGb-761-treated, and EGb-761-treated groups. EGb-761 (100 mg/kg/day) and SMB (98 mg/kg/day) were administered by gastric gavage for 40 days. Oral administration of EGb-761 restored SMB-induced decrease in body weight and prevented SMB-induced thrombocytopenia, leukocytosis, and anemia. Furthermore, EGb-761-treatment protected against SMB-induced liver and kidney injury depicted by decreased serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, bilirubin, creatinine, urea, uric acid, and albumin. Furthermore, EGb-761 treatment attenuated SMB-driven dyslipidemia and metabolic acidosis. Besides, EGb-761 supplementation abrogated SMB-driven oxidative stress as depicted by stabilized reduced glutathione (GSH) levels in the brain, liver, kidney, spleen, heart, and lungs. SMB induced a significant increase of tissue levels of malondialdehyde (MDA), serum nitric oxide (NO), interferon-gamma (IFN-γ) and tumor necrosis factor-α (TNF-α) which were abrogated by EGb-761 treatment. In conclusion, these results deepen our understanding of EGb-761 in light of various detrimental effects of SMB-driven toxicities. These findings provide a novel approach that can be optimized for preventing or treating exposure due to SMB toxicity.

The Role of Progranulin (PGRN) in the Pathogenesis of Ischemic Stroke

Stroke is a life-threatening medical condition and is a leading cause of disability. Cerebral ischemia is characterized by a distinct inflammatory response starting with the production of various cytokines and other inflammation-related agents. Progranulin (PGRN), a multifunctional protein, is critical in diverse physiological reactions, such as cell proliferation, inflammation, wound healing, and nervous system development. A mature PGRN is anti-inflammatory, while granulin, its derivative, conversely induces pro-inflammatory cytokine expression. PGRN is significantly involved in the brain tissue and its damage, for example, improving mood and cognitive disorders caused by cerebral ischemia. It may also have protective effects against nerve and spinal cord injuries by inhibiting neuroinflammatory response and apoptosis or it may be related to the proliferation, accumulation, differentiation, and activation of microglia. PGRN is a neurotrophic factor in the central nervous system. It may increase post-stroke neurogenesis of the subventricular zone (SVZ), which is particularly important in improving long-term brain function following cerebral ischemia. The neurogenesis enhanced via PGRN in the ischemic brain SVZ may be attributed to the induction of PI3K/AKT and MAPK/ERK signaling routes. PGRN can also promote the proliferation of neural stem/progenitor cells through PI3K/AKT signaling pathway. PGRN increases hippocampal neurogenesis, reducing anxiety and impaired spatial learning post-cerebral ischemia. PGRN alleviates cerebral ischemia/reperfusion injury by reducing endoplasmic reticulum stress and suppressing the NF-κB signaling pathway. PGRN can be introduced as a potent neuroprotective agent capable of improving post-ischemia neuronal actions, mainly by reducing and elevating the inflammatory and anti-inflammatory cytokines. Expression, storage, cleavage, and function of progranulin (PGRN) in the pathogenesis of ischemic stroke.

A novel extract from Ginkgo biloba inhibits neuroinflammation and maintains white matter integrity in experimental stroke

Ginkgo biloba L. leaf extract (GBE) has been added in many commercial herbal formulations such as EGb 761 and Shuxuening Injection to treat cardiovascular diseases and stroke worldwide. However, the comprehensive effects of GBE on cerebral ischemia remained unclear. Using a novel GBE (nGBE), which consists of all the compounds of traditional (t)GBE and one new compound, pinitol, we investigated its effect on inflammation, white matter integrity, and long-term neurological function in an experimental stroke model. Both transient middle cerebral artery occlusion (MCAO) and distal MCAO were conducted in male C57/BL6 mice. We found that nGBE significantly reduced infarct volume at 1, 3, and 14 days after ischemia. Sensorimotor and cognitive functions were superior in nGBE treated mice after MCAO. nGBE inhibited the release of IL-1β in the brain, promoted microglial ramification, and regulated the microglial M1 to M2 phenotype shift at 7 days post injury. In vitro analyses showed that nGBE treatment reduced the production of IL-1β and TNFα in primary microglia. Administration of nGBE also decreased the SMI-32/MBP ratio and enhanced myelin integrity, thus exhibiting improved white matter integrity at 28 days post stroke. These findings demonstrate that nGBE protects against cerebral ischemia by inhibiting microglia-related inflammation and promoting white matter repair, suggesting that nGBE is a promising therapeutic strategy for long-term recovery after stroke.

Ginkgo Biloba and Long COVID: In Vivo and In Vitro Models for the Evaluation of Nanotherapeutic Efficacy

Coronavirus infections are neuroinvasive and can provoke injury to the central nervous system (CNS) and long-term illness consequences. They may be associated with inflammatory processes due to cellular oxidative stress and an imbalanced antioxidant system. The ability of phytochemicals with antioxidant and anti-inflammatory activities, such as Ginkgo biloba, to alleviate neurological complications and brain tissue damage has attracted strong ongoing interest in the neurotherapeutic management of long COVID. Ginkgo biloba leaf extract (EGb) contains several bioactive ingredients, e.g., bilobalide, quercetin, ginkgolides A-C, kaempferol, isorhamnetin, and luteolin. They have various pharmacological and medicinal effects, including memory and cognitive improvement. Ginkgo biloba, through its anti-apoptotic, antioxidant, and anti-inflammatory activities, impacts cognitive function and other illness conditions like those in long COVID. While preclinical research on the antioxidant therapies for neuroprotection has shown promising results, clinical translation remains slow due to several challenges (e.g., low drug bioavailability, limited half-life, instability, restricted delivery to target tissues, and poor antioxidant capacity). This review emphasizes the advantages of nanotherapies using nanoparticle drug delivery approaches to overcome these challenges. Various experimental techniques shed light on the molecular mechanisms underlying the oxidative stress response in the nervous system and help comprehend the pathophysiology of the neurological sequelae of SARS-CoV-2 infection. To develop novel therapeutic agents and drug delivery systems, several methods for mimicking oxidative stress conditions have been used (e.g., lipid peroxidation products, mitochondrial respiratory chain inhibitors, and models of ischemic brain damage). We hypothesize the beneficial effects of EGb in the neurotherapeutic management of long-term COVID-19 symptoms, evaluated using either in vitro cellular or in vivo animal models of oxidative stress.

Ultrasound-assisted extraction and analysis of maidenhairtree polysaccharides

The maidenhairtree polysaccharides (MTPs) have important application prospects. So, the extraction, purification, structure, derivatization and biological activities of polysaccharides from leaves, fruits, and testae of maidenhairtree were disscussed. Polysaccharides were extracted by collaborative extraction methods such as ultrasound-assisted extraction and microwave-assisted extraction. The ultrasound-assisted extraction had higher content and higher efficiency. The structural characteristics and structure-activity relationship of maidenhairtree polysaccharides were studied in order to provide theoretical basis and technical support for the further development and utilization of maidenhairtree polysaccharides.

Natural Product Co-Metabolism and the Microbiota-Gut-Brain Axis in Age-Related Diseases

Complementary alternative medicine approaches are growing treatments of diseases to standard medicine practice. Many of these concepts are being adopted into standard practice and orthomolecular medicine. Age-related diseases, in particular neurodegenerative disorders, are particularly difficult to treat and a cure is likely a distant expectation for many of them. Shifting attention from pharmaceuticals to phytoceuticals and "bugs as drugs" represents a paradigm shift and novel approaches to intervention and management of age-related diseases and downstream effects of aging. Although they have their own unique pathologies, a growing body of evidence suggests Alzheimer's disease (AD) and vascular dementia (VaD) share common pathology and features. Moreover, normal metabolic processes contribute to detrimental aging and age-related diseases such as AD. Recognizing the role that the cerebral and cardiovascular pathways play in AD and age-related diseases represents a common denominator in their pathobiology. Understanding how prosaic foods and medications are co-metabolized with the gut microbiota (GMB) would advance personalized medicine and represents a paradigm shift in our view of human physiology and biochemistry. Extending that advance to include a new physiology for the advanced age-related diseases would provide new treatment targets for mild cognitive impairment, dementia, and neurodegeneration and may speed up medical advancements for these particularly devastating and debilitating diseases. Here, we explore selected foods and their derivatives and suggest new dementia treatment approaches for age-related diseases that focus on reexamining the role of the GMB.

Polysaccharides, Next Potential Agent for the Treatment of Epilepsy?

Epilepsy is a chronic neurological disorder. Current pharmacological therapies for epilepsy have limited efficacy that result in refractory epilepsy (RE). Owing to the limitations of conventional therapies, it is needed to develop new anti-epileptic drugs. The beneficial effects of polysaccharides from Chinese medicines, such as Lycium barbarum polysaccharides (COP) and Ganoderma lucidum polysaccharides (GLP), for treatment of epilepsy include regulation of inflammatory factors, neurotransmitters, ion channels, and antioxidant reactions. Especially, polysaccharides could be digested by intestinal microbial flora, referred as “intestinal brain organ” or “adult’s second brain”, may be the target for treatment of epilepsy. Actually, polysaccharides can effectively improve the type and quantity of intestinal flora such as bifidobacteria and lactic acid bacteria and achieve the purpose of treating epilepsy. Therefore, polysaccharides are hypothesized and discussed as potential agent for treatment of epilepsy.

The Use of Ginkgo Biloba L. as a Neuroprotective Agent in the Alzheimer's Disease

Alzheimer's disease, a neurodegenerative disease, is one of the most common causes of dementia if elderly people worldwide. Alzheimer's disease leads to the alienation of individuals and their exclusion from social and professional life. It is characterized mainly by the degradation of memory and disorientation, which occurs as a result of the loss of neuronal structure and function in different brain areas. In recent years, more and more attention has been paid to use in the treatment of natural bioactive compounds that will be effective in neurodegenerative diseases, including Alzheimer's disease. G. biloba L. and its most frequently used standardized extract (EGb 761), have been used for many years in supportive therapy and in the prevention of cognitive disorders. The paper presents an overview of reports on the pathogenesis of Alzheimer's disease, as well as a summary of the properties of G. biloba extract and its effects on the possible pathogenesis of the disease. By exploring more about the pathogenesis of the disease and the benefits of G. biloba extract for patients with Alzheimer's disease, it will be possible to create an individualized therapeutic protocol to optimize the treatment.

Neuroprotective Effect for Cerebral Ischemia by Natural Products: A Review

Natural products have a significant role in the prevention of disease and boosting of health in humans and animals. Stroke is a disease with high prevalence and incidence, the pathogenesis is a complex cascade reaction. In recent years, it’s reported that a vast number of natural products have demonstrated beneficial effects on stroke worldwide. Natural products have been discovered to modulate activities with multiple targets and signaling pathways to exert neuroprotection via direct or indirect effects on enzymes, such as kinases, regulatory receptors, and proteins. This review provides a comprehensive summary of the established pharmacological effects and multiple target mechanisms of natural products for cerebral ischemic injury in vitro and in vivo preclinical models, and their potential neuro-therapeutic applications. In addition, the biological activity of natural products is closely related to their structure, and the structure-activity relationship of most natural products in neuroprotection is lacking, which should be further explored in future. Overall, we stress on natural products for their role in neuroprotection, and this wide band of pharmacological or biological activities has made them suitable candidates for the treatment of stroke.

Differentially expressed genes induced by β-caryophyllene in a rat model of cerebral ischemia-reperfusion injury

Experimental studies have shown that β-caryophyllene (BCP) improved neurological deficits of cerebral ischemia-reperfusion injury (CIRI) rats resulting from Middle Cerebral Artery Occlusion (MCAO). However, research on targets of BCP on CIRI has not been completed. In this study, the mRNA sequencing was used to distinguish various therapeutic multiple targets of BCP on CIRI. Differentially expressed genes (DEGs) were identified from RNA-seq analysis. CIRI induced up-regulated genes (CIRI vs. Sham) and BCP -induced down-regulated genes (BCP vs CIRI) were identified. Significant DEGs were identified only that expressed in each of all samples. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis of significant DEGs were determined by cluster Profiler. Protein interactive network (PPI) was analyzed using the String tool and Hub genes was identified by cytoHubba. Transcription factor (TF) regulatory network for the potential Hub genes was constructed. Western blot and ELISA were used to verified hub genes and relative inflammatory cytokines. After mRNA sequencing, a total of 411 DEGs were filtered based on the 2 series (CIRI vs. Sham and CIRI vs. BCP), with Pax1, Cxcl3 and Ccl20 are the most remarkable ones reversed by BCP. GO analysis was represented by DEGs involved in multiple biological process such as extra-cellular matrix organization, leukocyte migration, regulation of angiogenesis, reactive oxygen species metabolic process, etc. KEGG analysis showed that DEGs participated several signaling pathways including MAPK signaling pathway (rno04010), Cytokine-cytokine receptor interaction (rno04060), JAK-STAT signaling pathway (rno04630), and others. The protein-protein interaction (PPI) network consisted of 339 nodes and 1945 connections, and top ten Hub genes were identified by cytoHubba such as TIMP1, MMP-9, and STAT3. Subsequently, a TFs-miRNAs-targets regulatory network was established, involving 6 TFs, 5 miRNAs, and 10 hub genes, consisting of several regulated models such as Brd4 - rno-let-7e - Mmp9, Brd4 - rno-let-7i - Stat3, and Hnf4a- rno-let-7b -Timp1. Finally, western blot demonstrated that BCP could inhibit the increased TIMP1, MMP-9 and STAT3 expression in rat brains after I/R. ELISA represented that BCP could suppress inflammatory cytokines caused by CIRI and present anti-oxidative property. In conclusion, this study shows that the intervention of BCP can significantly reduce neurologic deficit, improve the cerebral ischemia, and a total of ten hub genes were found closely related to the treatment of BCP on CIRI. Prudent experimental validation suggests that the BCP might have the neuro-protective effects in CIRI by decreasing the expression of MMP-9 and TIMP-1, STAT3. In a sense, this study reveals that the MMP-9/TIMP-1 signaling pathway may be involved in the injury after CIRI and thus provides a new treatment strategy as well as a researching method for stroke.

Isorhynchophylline Ameliorates Cerebral Ischemia/Reperfusion Injury by Inhibiting CX3CR1-Mediated Microglial Activation and Neuroinflammation

Reperfusion therapy is an effective way to rescue cerebral ischemic injury, but this therapy also shows the detrimental risk of devastating disorders and death due to the possible inflammatory responses involved in the pathologies. Hence, the therapy of ischemia/reperfusion (I/R) injury is a great challenge currently. Isorhynchophylline (IRN), a tetracyclic oxindole alkaloid extracted from Uncaria rhynchophylla, has previously shown neuroprotective and anti-inflammatory effects in microglial cells. This study systematically investigates the effect of IRN on I/R injury and its underlying mechanism. The effects of IRN on neuronal injury and microglia-mediated inflammatory response were assessed on a rat model with middle cerebral artery occlusion (MCAO) and reperfusion-induced injury. We found that IRN treatment attenuated the infarct volume and improved the neurological function in I/R injury rats. IRN treatment also reduced the neuronal death rate, brain water content, and aquaporin-4 expression in the ischemic penumbra of I/R injury rats’ brains. Besides, IRN treatment could inhibit the following process, including IκB-α degradation, NF-κB p65 activation, and CX3CR1 expression, as well as the microglial activation and inflammatory response. These findings suggest that IRN is a promising candidate to treat the cerebral I/R injury via inhibiting microglia activation and neuroinflammation.

Anti-cerebral ischemia reperfusion injury of polysaccharides: A review of the mechanisms

Cerebral ischemia-reperfusion injury can lead to a series of serious brain diseases and cause death or different degrees of disability. Polysaccharide is a kind of biological macromolecule with multiple pharmacological activities and has been proven that it may be used for the treatment of cerebral I/R injury in the future. By sorting out all relevant research from 2000 to 2020, we selected 74 references and identified 22 kinds of polysaccharides. Almost all of these polysaccharides are extracted from traditional Chinese medicine. Research shows that these polysaccharides can improve cerebral ischemia-reperfusion injury through anti-oxidative stress, inhibiting the neuroinflammation, glutamate neurotoxicity and neuronal apoptosis, and exerting neurotrophic effect. The specific mechanisms include clearing ROS and RNS, inhibiting the expression of inflammatory factors, maintaining mitochondrial homeostasis and blocking caspase cascade, regulating NMDA receptor and promoting angiogenesis. We hoped this review is instructive for researchers to design, research and develop polysaccharides.

Protective effects of polysaccharides on cerebral ischemia: A mini-review of the mechanisms

Cerebral ischemia, a common cerebrovascular disease, is one of the great threats to human health. Nowadays, many drugs used in the treatment of cerebral ischemia such as clot busting drugs, antiplatelet drugs, and neuroprotective drugs have limits. It is urgent finding new effective treatments for the patients. Researches have confirmed that many kinds of polysaccharides from natural resources possess therapeutic effects on cerebral ischemia, but are still lack of a comprehensively understanding. In this paper, based on the pathophysiology of cerebral ischemic injury, we summarize the latest discoveries and advancements of 29 kinds of polysaccharides, focusing on their ameliorating effects on cerebral ischemia and the underlying mechanisms. Several mechanisms are involved, mainly including antioxidant activities, anti-inflammatory activities, regulating neuron apoptosis, as well as resisting nitrosative stress injury. Besides, polysaccharides show protective effects through certain signaling pathways including PI3K/Akt, MAPK, and NF-κB, PARP-1/AIF, JNK3/c-Jun/Fas-L, and Nrf2/HO-1 signaling pathways. The main goal of this mini-review is to emphasize the important roles of polysaccharides in attenuating cerebral ischemic injury through the elucidation of mechanisms.

Natural Polysaccharide Carriers in Brain Delivery: Challenge and Perspective

Targeted drug delivery systems represent valuable tools to enhance the accumulation of therapeutics in the brain. Here, the presence of the blood brain barrier strongly hinders the passage of foreign substances, often limiting the effectiveness of pharmacological therapies. Among the plethora of materials used for the development of these systems, natural polysaccharides are attracting growing interest because of their biocompatibility, muco-adhesion, and chemical versatility which allow a wide range of carriers with tailored physico-chemical features to be synthetized. This review describes the state of the art in the field of targeted carriers based on natural polysaccharides over the last five years, focusing on the main targeting strategies, namely passive and active transport, stimuli-responsive materials and the administration route. In addition, in the last section, the efficacy of the reviewed carriers in each specific brain diseases is summarized and commented on in terms of enhancement of either blood brain barrier (BBB) permeation ability or drug bioavailability in the brain.

A network pharmacology approach to investigate the mechanism of Shuxuening injection in the treatment of ischemic stroke

ETHNOPHARMACOLOGICAL RELEVANCE

Shuxuening injection (SXNI), a popular herbal medicine, is an extract of Ginkgo biloba leaves (GBE), and is used to treat ischemic stroke (IS) in China. However, its specific active ingredients and molecular mechanisms in IS remain unclear.

AIM OF THE STUDY

The purpose of the research is to identify the main active ingredients in GBE and explore its molecular mechanisms in the treatment of IS.

MATERIALS AND METHODS

The main active components of GBE were discerned through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis (TCMSP), Traditional Chinese Medicine Integrated Database (TCMID), Bioinformatics Analysis Tool for Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM) database, and absorption, distribution, metabolism and excretion (ADME) analysis. The targets related to IS were obtained using Genecards, Online Mendelian Inheritance in Man (OMIM), Therapeutic Target Database (TTD), and Disgenet. We discovered an intersection of genes. Subsequently, protein-protein interaction (PPI) networks were constructed with Cytoscape 3.7.1 and the String database. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to analyze the intersection of targets via the Database for Annotation, Visualization, and Integrated Discovery (DAVID) 6.8. Built on the above analysis, we made a Compound-Target-Pathway (C-T-P) network. Autodock Vina was used for molecular docking analysis. Maestro 11.9 was used to calculate the root-mean-square deviation (RMSD). Animal experiments were performed to verify the core targets. Triphenyl tetrazolium chloride (TTC) staining was used to calculate the infarct volume in rats. Hematoxylin-eosin (HE) staining was employed to observe the morphology of hippocampal neuron cells. RT-qPCR was applied to detect relative mRNA levels, and protein expression was determined using Western blotting.

RESULTS

Molecular docking showed that PTGS2, NOS3 and CASP3 docked with small molecule compounds. According to RT-qPCR and Western blotting, mRNA and protein expression of PTGS2 and CASP3 were up-regulated (P < 0.05), and mRNA and protein levels of NOS3 were down-regulated (P < 0.05).

CONCLUSIONS

SXNI can treat IS through multiple targets and routes, and reduce the apoptosis of neuron cells in brain tissue by inhibiting inflammation and regulating the level of oxidative stress, thereby protecting rats brain tissue.

Astragalin alleviates cerebral ischemia-reperfusion injury by improving anti-oxidant and anti-inflammatory activities and inhibiting apoptosis pathway in rats

BACKGROUND

Astragalin (AG), a flavonoid from many traditional herbs and medicinal plants, has been described to exhibit in vitro anti-inflammatory activity. The paper aimed to study the effects of astragalin on anti-inflammatory, anti-oxidative ability and apoptosis signaling pathway in brain tissue of rats with cerebral ischemia-reperfusion injury, and to explore its possible mechanism.

METHODS

The rat model of focal cerebral ischemia-reperfusion injury was established by suture method. It was randomly divided into 5 groups, sham operation group, ischemia-reperfusion (I/R) treatment group, and astragalin treatment I / R group (12.5, 25, 50 mg / kg). After 24 h of reperfusion, the neurological deficits of the rats were analyzed and HE staining was performed. The volume of cerebral infarction was calculated by triphenyltetrazolium chloride (TTC) staining, and the apoptosis of nerve cells was detected by TUNEL staining. In addition, the content of malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase (SOD), glutathione (GSH) assay and glutathione peroxidase (GSH-Px) were measured in rat brain tissue. Western blot analysis was used to determine the expression of related proteins.

RESULTS

Compared with I/R group, the neurological deficit score and infarct volume of I/R rats were reduced in the astragalin treatment group. In the astragalin treatment group, MDA and NO levels in I/R rats were reduced, antioxidant enzymes and superoxide dismutase (SOD) activity were increased. In the astragalin treatment group, NF-κB (p65) and cyclooxygenase-2 (COX-2) expression levels were down-regulated, NF-E2-related factor 2 (Nrf2) nucleus and heme oxygenase-1 (HO-1) protein expression levels were up-regulated. In addition, the astragalin treatment can inhibit apoptosis, down-regulate Bax and cleaved caspase-3 expression, up-regulate Bcl-Xl expression.

CONCLUSION

The antioxidant properties of astragalin may play an important role in improving cerebral ischemia-reperfusion injury.

Phytic acid exerts protective effects in cerebral ischemia-reperfusion injury by activating the anti-oxidative protein sestrin2

Cerebral ischemia reperfusion (I/R) is a therapeutic strategy for ischemia; however, it usually causes injury by the aspect of inflammation and neuron apoptosis. This investigation aims to investigate the protective effects of phytic acid (IP6) for cerebral I/R injury in vitro. PC-12 cells under Oxygen and glucose deprivation/reperfusion (OGD/R) were performed to mimic cerebral I/R. IP6 was pretreated before PC-12 cells under OGD/R treatment. The data showed that IP6 activated the expression of sestrin2 in OGD/R injured PC-12 cells. IP6 inhibited OGD/R induced inflammation, oxidative stress, and apoptosis by activating sestrin2. Besides, p38 MAPK may mediate the effects of sestrin2 activated by IP6. Therefore, IP6 can be a potential drug to prevent neurological damage in cerebral I/R injury.

Hypobaric hypoxia induced fear and extinction memory impairment and effect of Ginkgo biloba in its amelioration: Behavioral, neurochemical and molecular correlates

Regulated fear and extinction memory is essential for balanced behavioral response. Limbic brain regions are susceptible to hypobaric hypoxia (HH) and are putative target for fear extinction deficit and dysregulation. The present study aimed to examine the effect of HH and Ginkgo biloba extract (GBE) on fear and extinction memory with the underlying mechanism. Adult male Sprague-Dawley rats were evaluated for fear extinction and anxious behavior following GBE administration during HH exposure. Blood and tissue (PFC, hippocampus and amygdala) samples were collected for biochemical, morphological and molecular studies. Results revealed deficit in contextual and cued fear extinction following 3 days of HH exposure. Increased corticosterone, glutamate with decreased GABA level was found with marked pyknosis, decrease in apical dendritic length and number of functional spines. Decline in mRNA expression level of synaptic plasticity genes and immunoreactivity of BDNF, synaptophysin, PSD95, spinophilin was observed following HH exposure. GBE administration during HH exposure improved fear and extinction memory along with decline in anxious behavior. It restored corticosterone, glutamate and GABA levels with an increase in apical dendritic length and number of functional spines with a reduction in pyknosis. It also improved mRNA expression level and immunoreactivity of neurotrophic and synaptic proteins. The present study is the first which demonstrates fear extinction deficit and anxious behavior following HH exposure. GBE administration ameliorated fear and extinction memory dysregulation by restoration of neurotransmitter levels, neuronal pyknosis and synaptic connections along with improved neurotrophic and synaptic protein expressions.

Targeting Oxidative Stress and Inflammation to Prevent Ischemia-Reperfusion Injury

The cerebral ischemia injury can result in neuronal death and/or functional impairment, which leads to further damage and dysfunction after recovery of blood supply. Cerebral ischemia/reperfusion injury (CIRI) often causes irreversible brain damage and neuronal injury and death, which involves many complex pathological processes including oxidative stress, amino acid toxicity, the release of endogenous substances, inflammation and apoptosis. Oxidative stress and inflammation are interactive and play critical roles in ischemia/reperfusion injury in the brain. Oxidative stress is important in the pathological process of ischemic stroke and is critical for the cascade development of ischemic injury. Oxidative stress is caused by reactive oxygen species (ROS) during cerebral ischemia and is more likely to lead to cell death and ultimately brain death after reperfusion. During reperfusion especially, superoxide anion free radicals, hydroxyl free radicals, and nitric oxide (NO) are produced, which can cause lipid peroxidation, inflammation and cell apoptosis. Inflammation alters the balance between pro-inflammatory and anti-inflammatory factors in cerebral ischemic injury. Inflammatory factors can therefore stimulate or exacerbate inflammation and aggravate ischemic injury. Neuroprotective therapies for various stages of the cerebral ischemia cascade response have received widespread attention. At present, neuroprotective drugs mainly include free radical scavengers, anti-inflammatory agents, and anti-apoptotic agents. However, the molecular mechanisms of the interaction between oxidative stress and inflammation, and their interplay with different types of programmed cell death in ischemia/reperfusion injury are unclear. The development of a suitable method for combination therapy has become a hot topic.

Protective effect of glycyrrhizic acid on cerebral ischemia/reperfusion injury via inhibiting HMGB1-mediated TLR4/NF-κB pathway

Cerebral ischemia is caused by various disorders, such as stroke, myocardial infarction, or peripheral vascular disease. The purpose of this paper was to investigate the effects of glycyrrhizic acid (GA) on cerebral ischemia/reperfusion (I/R) injury. Middle cerebral artery occlusion was established to evaluate the effects of GA on cerebral ischemia. In this study, our results showed that GA could dramatically decrease cerebral edema, reduce the neurological deficits, and smaller brain infarct volume was found in the GA treatment group. In serum and brain tissue, GA also increased superoxide dismutase activity. In addition, in serum and brain tissue, GA also dramatically inhibited the secretion of inflammatory cytokines, including interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α. Moreover, GA inhibited the expressions of high-mobility group protein box-1 (HMGB1)-mediated TLR4/NF-κB pathway. Our data determined that GA may provide protective effect on the I/R-induced cerebral ischemia disease.

Neuroprotective Effect of Ginkgo Biloba Extract Against Hypoxic Retinal Ganglion Cell Degeneration In Vitro and In Vivo

Hypoxia-induced oxidative stress and disturbed microvascular circulation are both associated with pathogenesis of glaucoma. Ginkgo biloba extract (GBE) has been reported to have positive pharmacological effects on oxidative stress and impaired vascular circulation. This study aimed to investigate the neuroprotective effect of GBE against hypoxic injury to retinal ganglion cells (RGCs) both in vitro and in vivo. The rat RGC line was used, and oxidative stress was induced by hydrogen peroxide (H₂O₂) in vitro. EGb 761, a standardized GBE, or vehicle was applied to RGCs. Hypoxic optic nerve injury in vivo was induced by clamping the optic nerve of rats with a "microserrefine clip" with an applicator, which was applied without crushing the optic nerve. This method is different from "optic nerve crush model" and does not involve elevation of intraocular pressure, and may serve as a possible normal tension glaucoma animal model. EGb 761 at various concentrations or vehicle was administered intraperitoneally. RGC density was measured to estimate the survival both in vitro and in vivo. The survival of RGCs was significantly (P < .001) higher upon treatment with 1 or 5 μg/mL of EGb 761 compared with vehicle after oxidative stress in vitro. RGC density upon treatment with EGb 761 of 100 mg/kg (1465.6 ± 175 cells/mm²) or 250 mg/kg (1307.6 ± 213 cells/mm²) was significantly higher (P < .01, P < .05, respectively) than that obtained with vehicle (876.3 ± 136 cells/mm²) in vivo. Our results suggest that GBE has neuroprotective effect on RGCs against hypoxic injury both in vitro and in vivo.

Antioxidant, anti-hyperlipidemia and hepatic protection of enzyme-assisted Morehella esculenta polysaccharide

The aims of this work were to investigate the antioxidant, anti-hyperlipidemia and hepatic protection of Morehella esculenta polysaccharide (MPS) from fruiting body and its enzyme-assisted MPS (EnMPS). The in vitro scavenging rates of EnMPS at 600 mg/L on superoxide, hydroxyl and 1,1‑diphenyl‑2‑pyrazole hydrazide (DPPH) radicals were 76.92 ± 2.61%, 66.74 ± 2.56% and 75.78 ± 2.4%, higher than those of MPS, respectively. Animals experiments showed that the EnMPS exhibited superior abilities of reducing hepatic lipid levels by monitoring the serum enzyme activities (ALP, ALT, ALB and AST) and serum lipid levels (CK, TC, TG, HDL-C, LDL-C and LDH), enhancing the hepatic antioxidant enzymes (FFA, SOD, CAT and T-AOC) and decreasing the lipid peroxidation (MDA and MPO). The results suggested that the EnMPS can act as a natural candidate for developing drugs to reduce blood lipids, resist oxidation and protect the liver.

Tnfrsf12a-Mediated Atherosclerosis Signaling and Inflammatory Response as a Common Protection Mechanism of Shuxuening Injection Against Both Myocardial and Cerebral Ischemia-Reperfusion Injuries

Shuxuening injection (SXNI) is a widely prescribed herbal medicine of Ginkgo biloba extract (EGB) for cerebral and cardiovascular diseases in China. However, its curative effects on ischemic stroke and heart diseases and the underlying mechanisms remain unknown. Taking an integrated approach of RNA-seq and network pharmacology analysis, we compared transcriptome profiles of brain and heart ischemia reperfusion injury in C57BL/6J mice to identify common and differential target genes by SXNI. Models for myocardial ischemia reperfusion injury (MIRI) by ligating left anterior descending coronary artery (LAD) for 30 min ischemia and 24 h reperfusion and cerebral ischemia reperfusion injury (CIRI) by middle cerebral artery occlusion (MCAO) for 90 min ischemia and 24 h reperfusion were employed to identify the common mechanisms of SXNI on both cerebral and myocardial ischemia reperfusion. In the CIRI model, ischemic infarct volume was markedly decreased after pre-treatment with SXNI at 0.5, 2.5, and 12.5 mL/kg. In the MIRI model, pre-treatment with SXNI at 2.5 and 12.5 mL/kg improved cardiac function and coronary blood flow and decreased myocardial infarction area. Besides, SXNI at 2.5 mL/kg also markedly reduced the levels of LDH, AST, CK-MB, and CK in serum. RNA-seq analysis identified 329 differentially expressed genes (DEGs) in brain and 94 DEGs in heart after SXNI treatment in CIRI or MIRI models, respectively. Core analysis by Ingenuity Pathway Analysis (IPA) revealed that atherosclerosis signaling and inflammatory response were top-ranked in the target profiles for both CIRI and MIRI after pre-treatment with SXNI. Specifically, Tnfrsf12a was recognized as an important common target, and was regulated by SXNI in CIRI and MIRI. In conclusion, our study showed that SXNI effectively protects brain and heart from I/R injuries via a common Tnfrsf12a-mediated pathway involving atherosclerosis signaling and inflammatory response. It provides a novel knowledge of active ingredients of Ginkgo biloba on cardio-cerebral vascular diseases in future clinical application.

Protective effect of the standardized leaf extract of Ginkgo biloba (EGb761) against hypertension-induced renal injury in rats

BACKGROUND

Ginkgo biloba leaves extract has been widely used worldwide to protect against oxidative stress-induced cell damage and improves blood circulation.

METHODS

The potential protective role of the standardized leaf extract of Ginkgo biloba (EGb761) on hypertension-induced renal injury was investigated in rats. Hypertension was induced in rats by L-NAME.

RESULT

Repeated treatment with EGb761 produced progressive reductions in the systolic, diastolic and mean arterial blood pressure. Also, EGb761 increased the progressive reductions in blood pressure induced by losartan. Hypertension-induced marked elevation of renal malondialdehyde (MDA) and nitrite levels and reduction of reduced glutathione (GSH) level were inhibited by EGb761. In addition, hypertension-induced increases in tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β)) levels in renal tissues were inhibited by EGb761. Also, treatment with EGb761 inhibited hypertension-induced decrease in endothelial nitric oxide synthase (eNOS) protein expression and increase in the protein expressions of inducible NO synthase (iNOS), TNF-α, IL-6 and IL-1B in the kidney tissues. EGb761 enhanced losartan effects on renal tissues oxidative stress, nitrite, and inflammatory markers levels and on protein expressions of eNOS, iNOS, TNF-α, IL-6 and IL-1B. effects.

CONCLUSIONS

These results indicate that EGb761 has the ability to protect against hypertension-induced renal injury.

Protective effect of the standardized extract of ginkgo biloba (EGb761) against hypertension with hypercholesterolemia-induced renal injury in rats: Insights in the underlying mechanisms

The potential protective role of the standardized leaf extract of ginkgo biloba (EGb761) on hypertension with hypercholesterolemia-induced renal injury was investigated in rats. Hypertension was induced by L-N(G)-nitroarginine methyl ester (L-NAME) and hypercholesterolemia was induced by feeding rats with a diet containing 1% cholesterol. In these animals repeated treatment with EGb761 produced a progressive reduction in the systolic, diastolic and mean arterial blood pressure (BP). EGb761 increased the progressive reduction in the systolic, diastolic and mean arterial BP induced by repeated administration of losartan with simvastatin. EGb761 corrected the compromised serum lipid profile and enhanced the effect of losartan with simvastatin on lipid profile. EGb761 protected against hypertension with hypercholesterolemia-induced renal injury as assessed by measurement of serum renal function markers and by histopathological examination. EGb761 enhanced the renoprotective effect of losartan with simvastatin in these rats. Concomitantly, hypertension with hypercholesterolemia-induced elevation of renal tissue malondialdehyde (MDA) and nitrite levels and reduction of intracellular reduced glutathione (GSH) level were inhibited by repeated treatment with EGb761. In addition, hypertension with hypercholesterolemia-induced increases in tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) levels in renal tissues were inhibited by treatment with EGb761. Also, EGb761 inhibited hypertension with hypercholesterolemia-induced decrease in endothelial nitric oxide synthase (eNOS) protein expression and increase in the protein expressions of inducible NO synthase (iNOS), TNF-α, IL-6 and IL-1β in the kidney tissues. Losartan with simvastatin produced similar effects on renal tissues oxidative stress, nitrite and inflammatory markers levels and on protein expressions of eNOS, iNOS, TNF-α, IL-6 and IL-1β. EGb761 enhanced losartan with simvastatin effects. These results indicate that EGb761 has the ability to protect against hypertension with hypercholesterolemia-induced renal injury. The ability of EGb761 to provide this renoprotective effect may positively correlate, besides its antihypertensive and antihypercholesterolemic effects, to its ability to suppress renal oxidative stress, nitrosative stress and inflammation.

Induction of mitochondrial-dependent apoptosis in T24 cells by a selenium (Se)-containing polysaccharide from Ginkgo biloba L. leaves

In the present study, a selenium (Se)-containing polysaccharide (Se-GBLP) was isolated and purified from the leaves of Ginkgo biloba L. Se-GBLP was further evaluated for its antitumor activity against human bladder cancer T24 cells together with the possible mechanism of action. Our results showed that treatment of T24 cells with Se-GBLP (50, 100 and 200μg/ml) for 48h significantly inhibited cell viability and induced apoptosis in a dose- dependent manner. This Se-GBLP-induced apoptosis is associated with an increased protein expression of pro-apoptotic Bax, decreased expression of anti-apoptotic Bcl-2, loss of mitochondrial membrane potential, and cleavage of caspase-9, caspase-3 and PARP, suggesting that Se-GBLP-induced apoptosis occurs through the mitochondria-dependent pathway. Se-GBLP therefore merits further investigation as a promising preventive and/or therapeutic agent against human bladder cancer.

Diosgenin attenuates the brain injury induced by transient focal cerebral ischemia-reperfusion in rats

The aim of the present study is to explore the potential cerebroprotection of diosgenin against the transient focal cerebral ischemia-reperfusion (I/R) injury and its possible underlying mechanisms. The diosgenin at two dose levels, namely 100 and 200mgkg(-1), was intragastrically administrated once daily for 7-day period prior to the surgery. Then, the rats were subjected to middle cerebral artery occlusion (MCAO) using the intraluminal thread for 90min. After 24h reperfusion, several diagnostic indicators were evaluated and all animals were sacrificed to harvest their brains and blood for subsequent biochemical analyses. The results indicated that diosgenin treatment significantly inhibited the death rate and improved the impaired neurological functions along with neurological deficit scores and cerebral infarct size as compared with the rats exposed to I/R insult without agents administration. The increase in the number of apoptotic cells determined by TUNEL in the hippocampus CA1 and cortex was also apparently attenuated in the diosgenin treatment group, which was closely correlated with suppression of Caspase-3 activity and Bax/Bcl-2 ratio. In addition the elevated concentrations of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) in blood serum of the I/R treated rats were reduced almost to their normal level. Further results obtained from the Western blotting analysis revealed that the protein expression of IκBα in the injured brain was up-regulated, while the p65 subunit of NF-κB was down-regulated in nucleus after the treatment. Collectively, this neuroprotection of diosgenin against I/R injury may be attained through its anti-apoptosis, anti-inflammation and intervening the NF-κB signal pathway properties. Due to the satisfactory findings, diosgenin might be a powerful therapeutic agent to combat the similar disease in future clinic.

Vitamins and nutrients as primary treatments in experimental brain injury: Clinical implications for nutraceutical therapies

With the numerous failures of pharmaceuticals to treat traumatic brain injury in humans, more researchers have become interested in combination therapies. This is largely due to the multimodal nature of damage from injury, which causes excitotoxicity, oxidative stress, edema, neuroinflammation and cell death. Polydrug treatments have the potential to target multiple aspects of the secondary injury cascade, while many previous therapies focused on one particular aspect. Of specific note are vitamins, minerals and nutrients that can be utilized to supplement other therapies. Many of these have low toxicity, are already FDA approved and have minimal interactions with other drugs, making them attractive targets for therapeutics. Over the past 20 years, interest in supplementation and supraphysiologic dosing of nutrients for brain injury has increased and indeed many vitamins and nutrients now have a considerable body of the literature backing their use. Here, we review several of the prominent therapies in the category of nutraceutical treatment for brain injury in experimental models, including vitamins (B2, B3, B6, B9, C, D, E), herbs and traditional medicines (ginseng, Gingko biloba), flavonoids, and other nutrients (magnesium, zinc, carnitine, omega-3 fatty acids). While there is still much work to be done, several of these have strong potential for clinical therapies, particularly with regard to polydrug regimens. This article is part of a Special Issue entitled SI:Brain injury and recovery.

The Anti-Oxidant and Antitumor Properties of Plant Polysaccharides

Oxidative stress has been increasingly recognized as a major contributing factor in a variety of human diseases, from inflammation to cancer. Although certain parts of signaling pathways are still under investigation, detailed molecular mechanisms for the induction of diseases have been elucidated, especially the link between excessive oxygen reactive species (ROS) damage and tumorigenesis. Emerging evidence suggests anti-oxidant therapy can play a key role in treating those diseases. Among potential drug resources, plant polysaccharides are natural anti-oxidant constituents important for human health because of their long history in ethnopharmacology, wide availability and few side effects upon consumption. Plant polysaccharides have been shown to possess anti-oxidant, anti-inflammation, cell viability promotion, immune-regulation and antitumor functions in a number of disease models, both in laboratory studies and in the clinic. In this paper, we reviewed the research progress of signaling pathways involved in the initiation and progression of oxidative stress- and cancer-related diseases in humans. The natural sources, structural properties and biological actions of several common plant polysaccharides, including Lycium barbarum, Ginseng, Zizyphus Jujuba, Astragalus lentiginosus, and Ginkgo biloba are discussed in detail, with emphasis on their signaling pathways. All of the mentioned common plant polysaccharides have great potential to treat oxidative stress and cancinogenic disorders in cell models, animal disease models and clinical cases. ROS-centered pathways (e.g. mitochondrial autophagy, MAPK and JNK) and transcription factor-related pathways (e.g. NF-[Formula: see text]B and HIF) are frequently utilized by these polysaccharides with or without the further involvement of inflammatory and death receptor pathways. Some of the polysaccharides may also influence tumorigenic pathways, such as Wnt and p53 to play their anti-tumor roles. In addition, current problems and future directions for the application of those plant polysaccharides are also listed and discussed.

Momordica charantia polysaccharides could protect against cerebral ischemia/reperfusion injury through inhibiting oxidative stress mediated c-Jun N-terminal kinase 3 signaling pathway

Momordica charantia (MC) is a medicinal plant for stroke treatment in Traditional Chinese Medicine, but its active compounds and molecular targets are unknown yet. M. charantia polysaccharide (MCP) is one of the important bioactive components in MC. In the present study, we tested the hypothesis that MCP has neuroprotective effects against cerebral ischemia/reperfusion injury through scavenging superoxide (O2(-)), nitric oxide (NO) and peroxynitrite (ONOO(-)) and inhibiting c-Jun N-terminal protein kinase (JNK3) signaling cascades. We conducted experiments with in vivo global and focal cerebral ischemia/reperfusion rat models and in vitro oxygen glucose deprivation (OGD) neural cells. The effects of MCP on apoptotic cell death and infarction volume, the bioactivities of scavenging O2(-), NO and ONOO(-), inhibiting lipid peroxidation and modulating JNK3 signaling pathway were investigated. Major results are summarized as below: (1) MCP dose-dependently attenuated apoptotic cell death in neural cells under OGD condition in vitro and reduced infarction volume in ischemic brains in vivo; (2) MCP had directing scavenging effects on NO, O2(-) and ONOO(-) and inhibited lipid peroxidation; (3) MCP inhibited the activations of JNK3/c-Jun/Fas-L and JNK3/cytochrome C/caspases-3 signaling cascades in ischemic brains in vivo. Taken together, we conclude that MCP could be a promising neuroprotective ingredient of M. charantia and its mechanisms could be at least in part attributed to its antioxidant activities and inhibiting JNK3 signaling cascades during cerebral ischemia/reperfusion injury.