Ruscogenin reduces cerebral ischemic injury via NF-κB-mediated inflammatory pathway in the mouse model of experimental stroke

From Plant to Pathway: Molecular Mechanisms of Ruscogenin in Preventing Amyloid-Beta Aggregation through Computational and Experimental Approaches

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline, extracellular amyloid-β (Aβ) plaque accumulation, and intracellular neurofibrillary tangles. Recent efforts to find effective therapies have increased interest in natural compounds with multifaceted effects on AD pathology. This study explores natural compounds for their potential to mitigate AD pathology using molecular docking, ADME screening, and in vitro assays, with ruscogenin─a steroidal sapogenin from Ruscus aculeatus─emerging as a promising candidate. Ruscogenin, known for its antioxidant and anti-inflammatory properties, was investigated for its effects on Aβ aggregation, a critical process in AD progression. In vitro assays demonstrated that ruscogenin inhibits Aβ oligomerization at equimolar and higher molar ratios. Molecular dynamics (MD) simulations further revealed that ruscogenin targets aggregation-prone regions, reducing noncovalent interactions and the solvent-accessible surface area of Aβ aggregates. These effects were concentration-dependent, with higher concentrations yielding optimal inhibition, pointing to a multiphasic behavior in ruscogenin's modulation of Aβ aggregation. This study highlights ruscogenin's potential as a natural therapeutic agent for AD, capable of addressing both oxidative stress and inflammation. The findings lay the groundwork for further exploration of ruscogenin-based interventions and underscore the broader potential of natural compounds in AD treatment strategies.

Modification of natural compounds through biotransformation process by microorganisms and their pharmacological properties

The biotransformation of natural compounds by fungal microorganisms is a complex biochemical process. Tandem whole-cell biotransformation offers a promising, alternative, and cost-effective method for modifying of bioactive novel compounds. This approach is particularly beneficial for structurally complex natural products that are difficult to be synthesized through traditional synthetic methods. Biotransformation also provides significant regio- and stereoselectivity, making it a valuable tool for the chemical modification of natural compounds. By utilizing microbial conversion reactions, the biological activity and structural diversity of natural products can be enhanced. In this review, we have summarized 282 novel metabolites resulting from microbial transformation by various microorganisms. We discussed the chemical structures and pharmacological properties of these novel biotransformation products. The review would assist scientists working in the fields of biotechnology, organic chemistry, medicinal chemistry, and pharmacology.

Ruscogenin Exerts Anxiolytic-Like Effect via Microglial NF-κB/MAPKs/NLRP3 Signaling Pathways in Mouse Model of Chronic Inflammatory Pain

Long-term inflammation can cause chronic pain and trigger patients' anxiety by sensitizing the central nervous system. However, effective drugs with few side effects for treating chronic pain-induced anxiety are still lacking. The anxiolytic and anti-inflammatory effects of ruscogenin (RUS), an important active compound in Ophiopogon japonicus, were evaluated in a mouse model of chronic inflammatory pain and N9 cells. RUS (5, 10, or 20 mg/kg/day, i.g.) was administered once daily for 7 days after CFA injection; pain- and anxiety-like behaviors were assessed in mice. Anti-inflammatory effect of RUS (0.1, 1, 10 μM) on N9 microglia after LPS treatment was evaluated. Inflammatory markers (TNF-α, IL-1β, IL-6, CD86, IL-4, ARG-1, and CD206) were measured using qPCR. The levels of IBA1, ROS, NF-κB, TLR4, P-IKK, P-IκBα, and P65, MAPKs (ERK, JNK, and P38), NLRP3 (caspase-1, ASC, and NLRP3) were detected by Western blotting or immunofluorescence staining. The potential target of RUS was validated by molecular docking and adeno-associated virus injection. Mice in CFA group exhibited allodynia and anxiety-like behaviors. LPS induced neuroinflammation in N9 cells. Both CFA and LPS increased the levels of IBA1, ROS, and inflammatory markers. RUS (10 mg/kg in vivo and 1 μM in vitro) alleviated these alterations through NF-κB/MAPKs/NLRP3 signaling pathways but had no effect on pain hypersensitivity. TLR4 strongly interacted with RUS, and TLR4 overexpression abolished the effects of RUS on anxiety and neuroinflammation. RUS exerts anti-inflammatory and anxiolytic effects via TLR4-mediated NF-κB/MAPKs/NLRP3 signaling pathways, which provides a basis for the treatment of chronic pain-induced anxiety.

Natural herbal extract roles and mechanisms in treating cerebral ischemia: A systematic review

Background

Stroke has been the focus of medical research due to its serious consequences and sequelae. Among the tens of millions of new stroke patients every year, cerebral ischemia patients account for the vast majority. While cerebral ischemia drug research and development is still ongoing, most drugs are terminated at preclinical stages due to their unacceptable toxic side effects. In recent years, natural herbs have received considerable attention in the pharmaceutical research and development field due to their low toxicity levels. Numerous studies have shown that natural herbs exert actions that cannot be ignored when treating cerebral ischemia.

Methods

We reviewed and summarized the therapeutic effects and mechanisms of different natural herbal extracts on cerebral ischemia to promote their application in this field. We used keywords such as "natural herbal extract," "herbal medicine," "Chinese herbal medicine" and "cerebral ischemia" to comprehensively search PubMed, ScienceDirect, ScienceNet, CNKI, and Wanfang databases, after which we conducted a detailed screening and review strategy.

Results

We included 120 high-quality studies up to 10 January 2024. Natural herbal extracts had significant roles in cerebral ischemia treatments via several molecular mechanisms, such as improving regional blood flow disorders, protecting the blood-brain barrier, and inhibiting neuronal apoptosis, oxidative stress and inflammatory responses.

Conclusion

Natural herbal extracts are represented by low toxicity and high curative effects, and will become indispensable therapeutic options in the cerebral ischemia treatment field.

Ruscogenin attenuates cartilage destruction in osteoarthritis through suppressing chondrocyte ferroptosis via Nrf2/SLC7A11/GPX4 signaling pathway

Osteoarthritis (OA) is a common joint degenerative disease, and chondrocyte injury is the main pathological and physiological change. Ruscogenin (Rus), a bioactive compound isolated from Radix Ophiopogon japonicus, exhibits various pharmacological effects. The aim of this research was to test the role and mechanism of Rus on OA both in vivo and in vitro. Destabilized medial meniscus (DMM)-induced OA model was established in vivo and IL-1β-stimulated mouse chondrocytes was used to explore the role of Rus on OA in vitro. In vivo, Rus exhibited protective effects against DMM-induced OA model. Rus could inhibit MMP1 and MMP3 expression in OA mice. In vitro, IL-1β-induced inflammation and degradation of extracellular matrix were inhibited by Rus, as confirmed by the inhibition of PGE2, NO, MMP1, and MMP3 by Rus. Also, IL-1β-induced ferroptosis was suppressed by Rus, as confirmed by the inhibition of MDA, iron, and ROS, as well as the upregulation of GSH, GPX4, Ferritin, Nrf2, and SLC7A11 expression induced by Rus. Furthermore, the suppression of Rus on IL-1β-induced inflammation, MMPs production, and ferroptosis were reversed when Nrf2 was knockdown. In conclusion, Rus attenuated OA progression through inhibiting chondrocyte ferroptosis via Nrf2/SLC7A11/GPX4 signaling pathway.

Ruscogenin timing administration mitigates cerebral ischemia-reperfusion injury through regulating circadian genes and activating Nrf2 pathway

BACKGROUND

Ruscogenin (Rus), a steroidal sapogenin extracted from Ophiopogon japonicus (L. f.) Ker-Gawl., has the effect of alleviating cerebral ischemia-reperfusion injury (IRI), acute lung injury. At present, the chronopharmacological effects of Rus are still unknown.

PURPOSE

This study explored the alleviating effect and mechanism of Rus timing administration on mice cerebral IRI.

METHODS

The animals in different groups were administrated Rus (10 mg/kg) by gavage at four time points (23:00-01:00, 05:00-07:00, 11:00-13:00, 17:00-19:00) respectively for 3 days. On the 4th day, middle cerebral artery occlusion (MCAO) surgery was operated during 5:00-7:00. Behavioral tests were executed and the brain was collected for infarct volume, qPCR and immunoblot detection. The levels of tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), interleukin-1beta (IL-1β) and inducible nitric oxide synthase (iNOS) were detected by qPCR. Glutathione (GSH), superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in serum and cerebral cortex were detected. The clock genes were tested by western blot. Based on these results, 17:00-19:00 was selected to administrate Rus for further mechanism study and Nrf2 blocker group was administrated all-trans-retinoic acid (ATRA) at 14:00 for 3 days.

RESULTS

Administration of Rus reduced cerebral infarcted volume, ameliorated the behavior score and upregulated the mRNA and protein expression of Per1, Bmal1, Clock, Rev-erbα, transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), quinone oxidoreductase 1 (NQO1). Administration of Rus during 17:00-19:00 had better preventive effect than other three time points. Combined administration of ATRA blunted the preventive effect of Rus.

CONCLUSION

The preventive effect of Rus is affected by the time of administration, which was regulated by Nrf2 pathway. Taken together, we provide solid evidence to suggest that different administration time point affect the effectiveness of Rus in alleviating IRI.

Inhibition of the NLRP3 Inflammasome Activation/Assembly through the Activation of the PI3K Pathway by Naloxone Protects Neural Stem Cells from Ischemic Condition

Naloxone is a well-known opioid antagonist and has been suggested to have neuroprotective effects in cerebral ischemia. We investigated whether naloxone exhibits anti-inflammatory and neuroprotective effects in neural stem cells (NSCs) injured by oxygen-glucose deprivation (OGD), whether it affects the NOD-like receptor protein 3 (NLRP3) inflammasome activation/assembly, and whether the role of the phosphatidylinositol 3-kinase (PI3K) pathway is important in the control of NLRP3 inflammasome activation/assembly by naloxone. Primary cultured NSCs were subjected to OGD and treated with different concentrations of naloxone. Cell viability, proliferation, and the intracellular signaling proteins associated with the PI3K pathway and NLRP3 inflammasome activation/assembly were evaluated in OGD-injured NSCs. OGD significantly reduced survival, proliferation, and migration and increased apoptosis of NSCs. However, treatment with naloxone significantly restored survival, proliferation, and migration and decreased apoptosis of NSCs. Moreover, OGD markedly increased NLRP3 inflammasome activation/assembly and cleaved caspase-1 and interleukin-1β levels in NSCs, but naloxone significantly attenuated these effects. These neuroprotective and anti-inflammatory effects of naloxone were eliminated when cells were treated with PI3K inhibitors. Our results suggest that NLRP3 inflammasome is a potential therapeutic target and that naloxone reduces ischemic injury in NSCs by inhibiting NLRP3 inflammasome activation/assembly mediated by the activation of the PI3K signaling pathway.

Regulatory mechanisms of natural compounds from traditional Chinese herbal medicines on the microglial response in ischemic stroke

BACKGROUND

Development of clinically effective neuroprotective agents for stroke therapy is still a challenging task. Microglia play a critical role in brain injury and recovery after ischemic stroke. Traditional Chinese herbal medicines (TCHMs) are based on a unique therapeutic principle, have various formulas, and have long been widely used to treat stroke. Therefore, the active compounds in TCHMs and their underlying mechanisms of action are attracting increasing attention in the field of stroke drug development.

PURPOSE

To summarize the regulatory mechanisms of TCHM-derived natural compounds on the microglial response in animal models of ischemic stroke.

METHODS

We searched studies published until 10 April 2023 in the Web of Science, PubMed, and ScienceDirect using the following keywords: natural compounds, natural products or phytochemicals, traditional Chinese Medicine or Chinese herbal medicine, microglia, and ischemic stroke. This review was prepared according to PRISMA (Preferred Reporting Item for Systematic Reviews and Meta-Analysis) guidelines.

RESULTS

Natural compounds derived from TCHMs can attenuate the M1 phenotype of microglia, which is involved in the detrimental inflammatory response, via inhibition of NF-κB, MAPKs, JAK/STAT, Notch, TLR4, P2X7R, CX3CR1, IL-17RA, the NLRP3 inflammasome, and pro-oxidant enzymes. Additionally, the neuroprotective response of microglia with the M2 phenotype can be enhanced by activating Nrf2/HO-1, PI3K/AKT, AMPK, PPARγ, SIRT1, CB2R, TREM2, nAChR, and IL-33/ST2. Several clinical trials showed that TCHM-derived natural compounds that regulate microglial responses have significant and safe therapeutic effects, but further well-designed clinical studies are needed.

CONCLUSIONS

Further research regarding the direct targets and potential pleiotropic or synergistic effects of natural compounds would provide a more reasonable approach for regulation of the microglial response with the possibility of successful stroke drug development.

Targeting pyroptosis as a preventive and therapeutic approach for stroke

Stroke has caused tremendous social stress worldwide, yet despite decades of research and development of new stroke drugs, most have failed and rt-PA (Recombinant tissue plasminogen activator) is still the accepted treatment for ischemic stroke. the complexity of the stroke mechanism has led to unsatisfactory efficacy of most drugs in clinical trials, indicating that there are still many gaps in our understanding of stroke. Pyroptosis is a programmed cell death (PCD) with inflammatory properties and are thought to be closely associated with stroke. Pyroptosis is regulated by the GSDMD of the gasdermin family, which when cleaved by Caspase-1/Caspase-11 into N-GSDMD with pore-forming activity can bind to the plasma membrane to form small 10-20 nm pores, which would allow the release of inflammatory factors IL-18 and IL-1β before cell rupture, greatly exacerbating the inflammatory response. The pyroptosis occurs mainly in the border zone of cerebral infarction, and glial cells, neuronal cells and brain microvascular endothelial cells (BMECs) all undergo pyroptosis after stroke, which largely exacerbates the breakdown of the blood-brain barrier (BBB) and thus aggravates brain injury. Therefore, pyroptosis may be a good direction for the treatment of stroke. In this review, we focus on the latest mechanisms of action of pyroptosis and the process by which pyroptosis regulates stroke development. We also suggest potential therapeutic stroke drugs that target the pyroptosis pathway, providing additional therapeutic strategies for the clinical management of stroke. The role of pyroptosis after stroke. After stroke, microglia first rush to the damaged area and polarize into M1 and M2 types. Under the influence of various stimuli, microglia undergo pyroptosis, release pro-inflammatory factors, and are converted to the M1 type; astrocytes and neuronal cells also undergo pyroptosis under the stimulation of various pro-inflammatory factors, leading to astrocyte death due to increased osmotic pressure in the membrane, resulting in water absorption and swelling until rupture. BMECs, the main structural component of the BBB, also undergo pyroptosis when stimulated by pro-inflammatory factors released from microglia and astrocytes, leading to the destruction of the structural integrity of the BBB, ultimately causing more severe brain damage. In addition, GSDMD in neutrophils mainly mediate the release of NETs rather than pyroptosis, which also aggravates brain injury. IL-10=interleukin-10; TGF-β = transforming growth factor-β; IL-18=interleukin-18; IL-1β = interleukin-1β; TNF-α = tumor necrosis factor-α; iNOS=induced nitrogen monoxide synthase; MMPs=Matrix metalloproteinases; GSDMD = gasdermin D; BMECs=brain microvascular endothelial cells; BBB = blood-brain barrier.

Plants and their Bioactive Compounds as a Possible Treatment for Traumatic Brain Injury-Induced Multi-Organ Dysfunction Syndrome

BACKGROUND & OBJECTIVE

Traumatic brain injury is an outcome of the physical or mechanical impact of external forces on the brain. Thus, the silent epidemic has complex pathophysiology affecting the brain along with extracranial or systemic complications in more than one organ system, including the heart, lungs, liver, kidney, gastrointestinal and endocrine system. which is referred to as Multi-Organ Dysfunction Syndrome. It is driven by three interconnected mechanisms such as systemic hyperinflammation, paroxysmal sympathetic hyperactivity, and immunosuppression-induced sepsis. These multifaceted pathologies accelerate the risk of mortality in clinical settings by interfering with the functions of distant organs through hypertension, cardiac arrhythmias, acute lung injury, neurogenic pulmonary edema, reduced gastrointestinal motility, Cushing ulcers, acute liver failure, acute kidney injury, coagulopathy, endocrine dysfunction, and many other impairments. The pharmaceutical treatment approach for this is highly specific in its mode of action and linked to a variety of side effects, including hallucinations, seizures, anaphylaxis, teeth, bone staining, etc. Therefore, alternative natural medicine treatments are widely accepted due to their broad complementary or synergistic effects on the physiological system with minor side effects.

CONCLUSION

This review is a compilation of the possible mechanisms behind the occurrence of multiorgan dysfunction and reported medicinal plants with organoprotective activity that have not been yet explored against traumatic brain injury and thereby, highlighting the marked possibilities of their effectiveness in the management of multiorgan dysfunction. As a result, we attempted to respond to the hypothesis against the usage of medicinal plants to treat neurodegenerative diseases.

Ruscogenin Ameliorated Sjögren's Syndrome by Inhibiting NLRP3 Inflammasome Activation

This article investigated the role and the specific mechanism of Ruscogenin in Sjögren's syndrome (SS). NOD/ShiLtJ mice were treated with Ruscogenin, and acinar cells isolated from submandibular glands were treated with TNF-α, Ruscogenin and transfected with NLRP3 overexpression plasmid. Salivary flow rate (SFR) was measured at weeks 11, 13, 15, 17, and 20. Histological analysis of the submandibular glands was conducted by hematoxylin-eosin staining assay. IL-6, IL-17, TNF-α, and IL-1β mRNA expression was detected through qRT-PCR. AQP 5, AQP 4, P2X7R, NLRP3, caspase 1, IL-1β, Bax, and Bcl-2 protein levels were tested by western blot. Cell apoptosis was assessed through acridine orange and propidium iodide (AO/PI) staining assay and flow cytometry assay. Ruscogenin ameliorated the SFR and submandibular gland inflammation of NOD/ShiLtJ mice. Ruscogenin promoted the preservation of acinar cells and suppressed inflammation-related factors (P2X7R, NLRP3, caspase 1, and IL-1β) in submandibular gland tissues of NOD/ShiLtJ mice. Ruscogenin inhibited acinar cell apoptosis in NOD/ShiLtJ mice and reversed TNF-α-induced apoptosis and inflammation of acinar cells. NLRP3 overexpression reversed the repressive effect of Ruscogenin on TNF-α-induced inflammation and apoptosis of acinar cells. Ruscogenin ameliorated SS by inhibiting NLRP3 inflammasome activation.

Ruscogenin Prevents Folic Acid-Induced Acute Kidney Damage by Inhibiting Rev-erbα/β-Mediated Ferroptosis

To investigate the pharmacodynamic effects of ruscogenin on acute kidney injury and the Rev-erbα/β regulation of ferroptosis intervention mechanism. The C57BL-6 mice were induced acute kidney injury with folic acid. Plasma, urine, and kidney samples were collected after intraperitoneal injection of ruscogenin (0.01, 0.1, and 1 mg/kg). We measured mouse kidney function indicators, including creatinine (CRE), blood urea nitrogen (BUN), N-acetyl-β-D-glucosidase (NAG), albumin, albumin and creatinine rate (ACR), renal index, and renal injury molecule-1 expression. Meanwhile, we detected the levels of ferroptosis indicators malondialdehyde (MDA), carbonylated proteins, iron ions, glutathione peroxidase 4 (GPX-4), and glutathione (GSH). The expression of solute carrier family 7 member 11 (Slc7a11), heme oxygenase-1 (HO-1), and Rev-erbα/β were detected by the Western blot and quantitative reverse transcription polymerase chain reaction (qRT-PCR), respectively. Ruscogenin (1 mg/kg) significantly reduced the index of folic acid-induced acute kidney injury and alleviated acute kidney injury. In kidney tissues, ruscogenin inhibited folic acid-induced Rev-erbα/β expression, restored HO-1 and SLC7A11 expression to normal levels, and alleviated ferroptosis. Ruscogenin ameliorates acute kidney injury via suppressing ferroptosis in kidney tissues through modulation of the Rev-erbα/β-SLC7A11/HO-1 pathway.

Anti-inflammatory and modulatory effects of steroidal saponins and sapogenins on cytokines: A review of pre-clinical research

BACKGROUND

Saponins are glycosides which, after acid hydrolysis, liberate sugar(s) and an aglycone (sapogenin) which can be triterpenoid or steroidal in nature. Steroidal saponins and sapogenins have attracted significant attention as important natural anti-inflammatory compounds capable of acting on the activity of several inflammatory cytokines in various inflammatory models.

PURPOSE

The aim of this review is to collect preclinical in vivo studies on the anti-inflammatory activity of steroidal saponins through the modulation of inflammatory cytokines.

STUDY DESIGN AND METHODS

This review was carried out through a specialized search in three databases, that were accessed between September and October, 2021, and the publication period of the articles was not limited. Information about the name of the steroidal saponins, the animals used, the dose and route of administration, the model of pain or inflammation used, the tissue and experimental method used in the measurement of the cytokines, and the results observed on the levels of cytokines was retrieved.

RESULTS

Forty-five (45) articles met the inclusion criteria, involving the saponins cantalasaponin-1, α-chaconine, dioscin, DT-13, lycoperoside H, protodioscin, α-solanine, timosaponin AIII and BII, trillin, and the sapogenins diosgenin, hecogenin, and ruscogenin. The surveys were carried out in seven different countries and only articles between 2007 and 2021 were found. The studies included in the review showed that the saponins and sapogenins were anti-inflammatory, antinociceptive and antioxidant and they modulate inflammatory cytokines mainly through the Nf-κB, TLR4 and MAPKs pathways.

CONCLUSION

Steroidal saponins and sapogenins are promising compounds in handling of pain and inflammation for the development of natural product-derived drugs. However, it is necessary to increase the methodological quality of preclinical studies, mainly blinding and sample size calculation.

Liriopogons (Genera Ophiopogon and Liriope, Asparagaceae): A Critical Review of the Phytochemical and Pharmacological Research

The closely related genera Liriope and Ophiopogon (Asparagaceae), collectively known in English as liriopogons, have similar therapeutic uses in treating cough, rheumatoid arthritis, and cleaning heat. The main aim of this review is to understand the current phytochemical and pharmacological knowledge including an assessment of the quality of the scientific evidence. A literature search was conducted in line with PRISMA guidelines, by retrieving available information up to 2020 from five online resources. The bioactive metabolites of liriopogons include steroidal saponins, flavonoids, polysaccharides, organic acids, phenols. Cardiovascular protective, anti-inflammatory, anti-diabetic, anti-oxidant, anti-cancer, neuroprotective, anti-viral, anti-acute myeloid leukemia and hepatoprotective effects have been at the center of attention. From a toxicological perspective Ophiopogon japonicus seems to be safe. Some problems with the quality of the pharmacological evidence stand out including the application of excessive dose level and methodological problems in the design. Additionally, a reasonable link between local/traditional uses and pharmacological assessment is often vague or not reflected in the text. Future researches on liriopogons are required to use rigorous scientific approaches in research on evidence-based natural products for the future benefits of patients.

Emerging immune and cell death mechanisms in stroke: Saponins as therapeutic candidates

The complexity of the ischemic cascade is based on the integrated crosstalk of every cell type in the neurovascular unit. Depending on the features of the ischemic insult, several cell death mechanisms are triggered, such as apoptosis, necroptosis, ferroptosis/oxytosis, ETosis or pyroptosis, leading to reactive astrogliosis. However, emerging evidence demonstrates a dual role for the immune system in stroke pathophysiology, where it exerts both detrimental and also beneficial functions. In this review, we discuss the relevance of several cell death modalities and the dual role of the immune system in stroke pathophysiology. We also provide an overview of some emerging immunomodulatory therapeutic strategies, amongst which saponins, which are promising candidates that exert multiple pharmacological effects.

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Several cell death mechanisms coexist in stroke pathophysiology.

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Neurons are more vulnerable to necroptosis than glial cells.

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Inhibitors of receptor-interacting protein kinases and of ferroptosis induce neuroprotection.

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Saponins exert modulatory effects on inflammation and neuronal cell death in stroke.

Targeting Common Signaling Pathways for the Treatment of Stroke and Alzheimer's: a Comprehensive Review

Neurodegenerative diseases such as stroke and Alzheimer's disease (AD) are two inter-related disorders that affect the neurons in the brain and central nervous system. Alzheimer's is a disease by undefined origin and causes. Stroke and its most common type, ischemic stroke (IS), occurs due to the blockade of cerebral blood vessels. As an important feature, both of disorders are associated with irreversible damages to the brain and nervous system. In this regard, finding common signaling pathways and the same molecular origin between these two diseases may be a promising way for their solution. On the basis of literature appraisal, the most common signaling cascades implicated in the pathogenesis of AD and stroke including notch, autophagy, inflammatory, and insulin signaling pathways were reviewed. Furthermore, current therapeutic strategies including natural and synthetic pharmaceuticals aiming modulation of respective signaling factors were scrutinized to ameliorate neural deficits in AD and stroke. Taken together, digging deeper in the common connections and signal targeting can be greatly helpful in understanding and unified treating of these disorders.

Ruscogenin attenuates sepsis-induced acute lung injury and pulmonary endothelial barrier dysfunction via TLR4/Src/p120-catenin/VE-cadherin signalling pathway

OBJECTIVES

Sepsis-associated acute lung injury (ALI) occurs with the highest morbidity and carries the highest mortality rates among the pathogenies of ALI. Ruscogenin (RUS) has been found to exhibit anti-inflammation property and rescue lipopolysaccharide-induced ALI, but little is known about its role in sepsis-triggered ALI. The aim of this study was to investigate the potential role of RUS in sepsis-induced ALI and the probable mechanism.

METHODS

Mice model of cecal ligation and puncture (CLP) was replicated, and three doses of RUS (0.01, 0.03 and 0.1 mg/kg) were administrated 1 h before CLP surgeries.

KEY FINDINGS

RUS significantly extended the survival time and attenuated the lung pathological injury, oedema and vascular leakage in sepsis-induced ALI mice. RUS efficiently decreased the level of MPO in lung tissue and the WBC, NEU counts in BALF. In addition, RUS rescued the expression of VE-cadherin and p120-catenin and suppressed the TLR4/Src signalling in lung tissue.

CONCLUSIONS

RUS attenuated sepsis-induced ALI via protecting pulmonary endothelial barrier and regulating TLR4/Src/p120-catenin/VE-cadherin signalling pathway.

Protective effects and mechanism of action of ruscogenin in a mouse model of ovalbumin-induced asthma

OBJECTIVE

Ruscogenin is a natural product exhibiting anti-inflammatory, antioxidant, and anti-apoptotic effects; however, its effectiveness for asthma management has not yet been reported. The aim of this study was to explore the role of ruscogenin in airway inflammation and apoptosis in asthma.

METHODS

In vivo, female 6- to 8-week-old CL57 mice were sensitized to ovalbumin and challenged intranasally for 7 days. One group was gavaged with ruscogenin before ovalbumin challenge. At the end of the challenge period, airway hyperresponsiveness and airway inflammation were evaluated. Enzyme-linked immunosorbent assay was used to estimate the oxidative stress levels. A terminal deoxynucleotidyl transferase dUDP nick-end labeling assay was used to determine the extent of apoptosis. Immunohistochemistry and western blotting were performed to examine VDAC1 expression. In vitro, human bronchial epithelial (HBE) cells were treated with H₂O₂, ruscogenin, or disulfonate salt, and flow cytometry was used to calculate the apoptosis ratio and detect mitochondrial calcium levels.

RESULTS

In vivo, ruscogenin improved airway hyperresponsiveness and airway inflammation, while reducing oxidative stress, the apoptosis ratio and VDAC1 expression in asthmatic lungs. In vitro, ruscogenin attenuated apoptosis in HBE cells by decreasing the levels of VDAC1 expression and mitochondrial calcium.

CONCLUSION

Ruscogenin reduced oxidative stress and apoptosis in the airway epithelium by inhibiting VDAC1 expression and mitochondrial handling of calcium.

Ruscogenin attenuates particulate matter-induced acute lung injury in mice via protecting pulmonary endothelial barrier and inhibiting TLR4 signaling pathway

The inhalation of particulate matter (PM) is closely related to respiratory damage, including acute lung injury (ALI), characterized by inflammatory fluid edema and disturbed alveolar-capillary permeability. Ruscogenin (RUS), the main active ingredient in the traditional Chinese medicine Ophiopogonis japonicus, has been found to exhibit anti-inflammatory activity and rescue LPS-induced ALI. In this study, we investigated whether and how RUS exerted therapeutic effects on PM-induced ALI. RUS (0.1, 0.3, 1 mg·kg-1·d-1) was orally administered to mice prior to or after intratracheal instillation of PM suspension (50 mg/kg). We showed that RUS administration either prior to or after PM challenge significantly attenuated PM-induced pathological injury, lung edema, vascular leakage and VE-cadherin expression in lung tissue. RUS administration significantly decreased the levels of cytokines IL-6 and IL-1β, as well as the levels of NO and MPO in both bronchoalveolar lavage fluid (BALF) and serum. RUS administration dose-dependently suppressed the phosphorylation of NF-κB p65 and the expression of TLR4 and MyD88 in lung tissue. Furthermore, TLR4 knockout partly diminished PM-induced lung injury, and abolished the protective effects of RUS in PM-instilled mice. In conclusion, RUS effectively alleviates PM-induced ALI probably by inhibition of vascular leakage and TLR4/MyD88 signaling. TLR4 might be crucial for PM to initiate pulmonary lesion and for RUS to exert efficacy against PM-induced lung injury.

Ophiopogonin A Alleviates Hemorrhagic Shock-Induced Renal Injury via Induction of Nrf2 Expression

Ophiopogonin, including Ophiopogonin A, B, C, D, is an effective active component of traditional Chinese medicine Ophiopogon japonicus which has a wide range of pharmacological effects such as protecting myocardial ischemia, resisting myocardial infarction, immune regulation, lowering blood glucose, and anti-tumor. However, the functions of ophiopogonin A on hemorrhagic shock (HS)-induced renal injury remain unclear. First, this study constructed an HS rat model and hypoxia HK-2 cell model to assess the effects of ophiopogonin A in vivo and in vitro. In vivo, HE and TUNEL staining show that ophiopogonin A dose-dependently inhibits HS-induced tissue damage and apoptosis. Moreover, ophiopogonin A dose-dependently downregulates the levels of blood urea nitrogen (BUN), creatinine (Cr), KIM-1, NGAL, iNOS, TNF-α, IL-1β, and IL-6 in HS rats kidney tissues, and decreases the number of MPO-positive cells. In vitro, we get similar results that ophiopogonin A dose-dependently improves hypoxia-induced HK-2 cell apoptosis and damage. In addition, ophiopogonin A dose-dependently increases the expression of NF E2-related factor 2 (Nrf2), while knockdown of Nrf2 reverses the functions of ophiopogonin A in vivo and in vitro. Furthermore, ophiopogonin A dose-dependently promotes the phosphorylation of ERK in HS kidney tissues and hypoxia-treated HK-2 cells, suggesting that ophiopogonin A functions via the p-ERK/ERK signaling pathway.

Syringin exerts neuroprotective effects in a rat model of cerebral ischemia through the FOXO3a/NF-κB pathway

Inflammation plays an important role in the pathogenesis of cerebral ischemia. Syringin (SYR) is an active substance isolated from Acanthopanax senticosus plants, and possesses anti-inflammatory and neuroprotective properties. However, its effects on cerebral ischemic injury, as well as the underlying molecular events, are still unclear. The purpose of this study was to investigate the effect of SYR in a rat model of cerebral ischemia and address the related molecular mechanism. A middle cerebral artery occlusion/reperfusion model (MCAO) was used to simulate ischemic injury. SYR treatment clearly reduced the infarct volume, decreased cerebral water content, improved the neurological score, and attenuated neuronal death. Moreover, SYR decreased the expression of NF-κB, IL-1β, IL-6, TNF-α, and MPO, promoted FOXO3a phosphorylation and cytoplasmic retention, and inhibited the nuclear translocation of NF-κB. FOXO3a knockdown by RNA interference significantly prevented SYR-induced inhibition of NF-κB-mediated inflammation. Confocal microscopy revealed that SYR reduced NF-κB translocation to the nucleus, and FOXO3a silencing reversed this effect. Finally, immunofluorescence and CO-IP experiments showed that SYR promoted the interaction between FOXO3a and NF-κB. In conclusion, SYR exerted a protective effect against brain I/R injury by reducing the inflammation accompanying cerebral ischemia. This effect was mediated by the FOXO3a /NF-κB pathway.

Potent therapeutic effects of ruscogenin on gastric ulcer established by acetic acid

BACKGROUND/OBJECTIVE

The present study investigated the potent therapeutic effects of Ruscogenin, main steroid sapogenin of traditional Chinese plant called 'Ophiopogon japonicas', on chronic ulcer model established with acetic acid in rats.

METHODS

24 rats were attenuated to the sham (2 ml/kg/day isotonic solution), control (untreated ulcer) and treatment (3 ml/kg/day ruscogenin) groups. After treatment for 2 weeks, gastric tissues were collected and prepared for light microscopic (H&E), immunohistochemical (Collagen I, III and IV) and biochemical analysis [Epidermal growth factor (EGF), Prostaglandin E2 (PGE2), Tumor Necrosis Factor alpha (TNF-α), Interleukin 6 and 8 (IL-6 and IL-8), Lipid Peroxidase (LPO), Myeloperoxidase (MPO), Glutathione (GSH) and Glutathione Peroxidase (GSH-Px)] and transmission electron microscopy (TEM).

RESULTS

Macroscopic scoring showed that the ulceration area of ruscogenin-treated group decreased compared with control group. Immunohistochemical analysis revealed ruscogenin ameliorated and restored the levels of Collagen I and IV to the levels of sham group. Tissue levels of EGF and PGE2 enhanced significantly in untreated ulcer group while were higher in treated ulcer group than the control group. TNF-α, IL-6, IL-8, LPO, MPO levels increased significantly in control group whereas decreased in treated rats after ruscogenin treatment. However, levels of GSH and GSH-Px increased significantly in treatment group. TEM showed chief cells and parietal cells of ulcer group having degenerated organelles while ruscogenin group had normal ultrastructure of cells.

CONCLUSION

There are potent anti-inflammatory and anti-oxidant effects of ruscogenin on gastric ulcer and may be successfully used as a safe and therapeutic agent in treatment of peptic ulcer.

Chinese Herbal Medicine and Acupuncture Reduced the Risk of Stroke After Bell's Palsy: A Population-Based Retrospective Cohort Study

Objectives: Patients with Bell's palsy are more likely to develop stroke than the general population. The therapeutic effect of Traditional Chinese Medicine (TCM) on the risk of stroke in patients with Bell's palsy is unknown. We investigated the risk of stroke according to TCM use in Bell's palsy patients. Design: Records obtained from Taiwan's National Health Insurance Research Database identified 9,863 patients with Bell's palsy, 238 of whom met study inclusion criteria and were categorized as TCM users (n = 119) or non-TCM users (n = 119). TCM treatment modalities and Chinese herbal medicine prescription patterns were analyzed. Cox proportional hazards regression analysis determined the risk of stroke. Results: TCM users were at lower risk of stroke compared with non-TCM users (adjusted hazard ratio [aHR] 0.19; 95% confidence interval [CI], 0.06-0.59; p < 0.004). In subgroup analyses, patients treated with both TCM and oral steroids were at significantly lower risk of stroke compared with those who used neither (aHR 0.05; 95% CI, 0.01-0.22; p < 0.001). The risk of stroke was also lower among those treated with TCM only (aHR 0.25; 95% CI, 0.11-0.59; p < 0.001) or oral steroids only (aHR 0.12; 95% CI, 0.03-0.39; p < 0.01), compared with patients using neither. Conclusion: TCM therapy may lower the risk of stroke after Bell's palsy. However, the retrospective nature of this study and characteristics of the database limit these observational findings. Our results deserve further verification in large-scale prospective studies.

Caspase-1 inhibition mediates neuroprotection in experimental stroke by polarizing M2 microglia/macrophage and suppressing NF-κB activation

Stroke is a life-threatening neurological disease with limited therapeutic options. Inflammation is believed to be involved in the pathogenesis of ischemic stroke and contribute to the degree of brain injury. Vx-765 is a potent, selective, small-molecule caspase-1 inhibitor. Current studies have shown the anti-inflammatory properties of vx-765 in various disease; however, the impact of vx-765 on the ischemic stroke is still unclear. In the present study, we determine the neuroprotective effect of vx-765 in mice subjected to transient middle cerebral artery occlusion (MCAO). We found that caspase-1 inhibition by administration of vx-765 ameliorated cerebral injury in mice after ischemic stroke by reducing infarct volume and ameliorating the neurological deficits. Mechanistically, we showed that the contribution of vx-765 to ischemic injuries may be associated with reducing microglial activation, and downregulating the production of associated pro inflammatory cytokines including IL-1β, TNF-α, and iNOS, as well as upregulating anti-inflammatory cytokines such as TGF-β and YM-1. Additionally, vx-765 altered the phenotype of microglia via switching the microglia polarization toward M2 phenotype, as demonstrably related to inhibition of the NF-κB activation. Our findings indicate that vx-765 protects against MCAO injury and attenuated microglia mediated neuroinflammation primarily by shifting microglia polarization from M1 phenotype toward M2 phenotype. Vx-765 might be a potential therapeutic drug for ameliorating ischemic stroke.

Connectivity map identifies luteolin as a treatment option of ischemic stroke by inhibiting MMP9 and activation of the PI3K/Akt signaling pathway

This study aimed to explore potential new drugs in the treatment of ischemic stroke by Connectivity Map (CMap) and to determine the role of luteolin on ischemic stroke according to its effects on matrix metalloproteinase-9 (MMP9) and PI3K/Akt signaling pathway. Based on published gene expression data, differentially expressed genes were obtained by microarray analysis. Potential compounds for ischemic stroke therapy were obtained by CMap analysis. Cytoscape and gene set enrichment analysis (GSEA) were used to discover signaling pathways connected to ischemic stroke. Cell apoptosis and viability were, respectively, evaluated by flow cytometry and an MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) assay. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis were used to test the expression of MMP9 and the PI3K/Akt signaling pathway-related proteins in human brain microvascular endothelial cells (HBMECs) and tissues. Additionally, the infarct volume after middle cerebral artery occlusion (MCAO) was determined by a TTC (2,3,5-triphenyltetrazolium chloride) assay. The microarray and CMap analyses identified luteolin as a promising compound for future therapies for ischemic stroke. Cytoscape and GSEA showed that the PI3K/Akt signaling pathway was crucial in ischemic stroke. Cell experiments revealed that luteolin enhanced cell viability and downregulated apoptosis via inhibiting MMP9 and activating the PI3K/Akt signaling pathway. Experiments performed in vivo also demonstrated that luteolin reduced the infarct volume. These results suggest that luteolin has potential in the treatment of ischemic stroke through inhibiting MMP9 and activating PI3K/Akt signaling pathway.

Resveratrol downregulates the TLR4 signaling pathway to reduce brain damage in a rat model of focal cerebral ischemia

Previous studies have demonstrated that inflammation and disruption of the blood-brain barrier (BBB) are important pathological processes during focal cerebral ischemia. Therefore, the present study evaluated the neuroprotective effects of resveratrol against brain damage, inflammation and BBB disruption in rats with focal cerebral ischemia and assessed the potential underlying molecular mechanisms. Sprague-Dawley rats underwent cerebral ischemia/reperfusion (IR) and then received intraperitoneal resveratrol (10 and 100 mg/kg) 2 h following the onset of ischemia. Following 24 h of ischemia, neurological deficit scores, cerebral infarctions, morphological characteristics, cerebral water content, myeloperoxidase (MPO) activity and Evans blue extravasation were assessed. Additionally, the protein expression levels of Toll-like receptor 4 (TLR4) and nuclear factor (NF)-κB p65 were detected using western blot analyses, the mRNA expression levels of cyclooxygenase-2 (COX-2) and matrix metalloproteinase-9 (MMP-9) were examined by reverse-transcription polymerase chain reaction, and tumor necrosis factor (TNF)-α and interleukin (IL)-1β blood levels were determined by ELISA. Resveratrol significantly reduced neurological deficit scores, cerebral infarct sizes, neuronal injury, MPO activity and EB content. Cerebral ischemia increased the expression levels of TLR4, NF-κB p65, COX-2, MMP-9, TNF-α and IL-1β, but all of these factors were reduced by resveratrol. In conclusion, the present data suggest that resveratrol reduces inflammation, BBB disruption and brain damage in rats following focal cerebral ischemia. Additionally, the neuroprotective effects of resveratrol against cerebral ischemia may be associated with downregulation of the TLR4 pathway.

Naloxone attenuates ischemic brain injury in rats through suppressing the NIK/IKKα/NF-κB and neuronal apoptotic pathways

Although naloxone has been documented to exert neuroprotection in animal model of cerebral ischemia, the mechanism is not well understood. In this present study we investigated whether naloxone affected the mitochondrial apoptotic pathway in ischemic brain injury of rats. SD rats were subjected to a permanent middle cerebral artery occlusion surgery, and received naloxone (0.5, 1, 2 mg/kg, i.v.) immediately after ischemia. Neurological deficits were evaluated 24 h after ischemia using the McGraw Stroke Index, and then the rats were killed, and the brains were collected for further analyses. We show that naloxone treatment dose-dependently decreased the infarction volume and morphological injury, improved motor behavioral function, and markedly curtailed brain edema. Furthermore, naloxone administration significantly inhibited the nuclear translocation of NF-κB p65 and decreased the levels of nuclear NF-κB p65 in the ischemic penumbra. Naloxone administration also dose-dependently increased the NF-κB inhibitory protein (IκBα) levels and attenuated phosphorylated NIK and IKKα levels in the ischemic penumbra. In addition, naloxone administration dose-dependently increased Bcl-2 levels, decreased Bax levels, stabilized the mitochondrial transmembrane potential, and inhibited cytochrome c release and caspase 3 and caspase 9 activation. These results indicate that the neuroprotective effects of naloxone against ischemic brain injury involve the inhibition of NF-κB activation via the suppression of the NIK/IKKα/IκBα pathway and the obstruction of the mitochondrial apoptotic pathway in neurons.

Role and mechanism of ROS scavengers in alleviating NLRP3-mediated inflammation

Inflammation, as a common immune response to various infections or injuries, can cause many dangerous and complicated diseases. Inflammasome is a protein complex playing a vital role in an inflammation process, and the nucleotide-binding oligomerization domain (NOD)-like receptor containing pyrin domain 3 (NLRP3) inflammasome has been the most-widely studied one. Recent evidence suggests the reactive oxygen species (ROS)-NLRP3 signaling pathway to be a possible NLRP3 inflammasome regulation model. Numerous recent preclinical reports indicate that application of antioxidants could scavenge excessive ROS and attenuate inflammatory responses through suppressing NLRP3 inflammasome activation. This article, at first, briefly overviews how ROS may mediate the regulation of NLRP3 inflammasome activation. Then, preclinical researches of various ROS scavengers for treating NLRP3 inflammasome-associated diseases are focused on and critically analyzed. Finally, the potential of antioxidant treatment as a therapy for inflammation is to be discussed, and perspectives on future research directions will be shared.

Ruscogenin suppressed the hepatocellular carcinoma metastasis via PI3K/Akt/mTOR signaling pathway

BACKGROUND

Hepatocellular carcinoma (HCC) is the third-leading cause of cancer-related mortality with poor prognosis and treatment. More effective strategies should be studied in HCC.

METHODS

After treated with ruscogenin, the cell proliferation was assessed by CCK-8 method. Cell migration and invasion were estimated using wound healing and transwell assays. Pathological changes of lung tissue were observed by HE staining and IHC methods. MMP-2, MMP-9, uPA, VEGF and HIF-1α levels were measured using ELISA, RT-qPCR and WB tests. PI3K/Akt/mTOR pathway related molecules were detected using WB analysis.

RESULTS

The results indicated the hypotoxicity of ruscogenin. Meanwhile, ruscogenin showed obvious interruption on the cancer cell migration and invasion, and inhibition on the metastatic foci in pulmonary tissue. Significantly, ruscogenin decreased the levels of MMP-2, MMP-9, uPA, VEGF and HIF-1α, down-regulated the phosphorylation of Akt, mTOR.

CONCLUSION

The present study indicated a novel use of ruscogenin in suppressing HCC metastasis by reducing the expression of MMP-2, MMP-9, uPA, VEGF and HIF-1α via regulating the PI3K/Akt/mTOR signaling pathway.

Targeting Cellular Stress Mechanisms and Metabolic Homeostasis by Chinese Herbal Drugs for Neuroprotection

Traditional Chinese medicine has been practiced for centuries in East Asia. Herbs are used to maintain health and cure disease. Certain Chinese herbs are known to protect and improve the brain, memory, and nervous system. To apply ancient knowledge to modern science, some major natural therapeutic compounds in herbs were extracted and evaluated in recent decades. Emerging studies have shown that herbal compounds have neuroprotective effects or can ameliorate neurodegenerative diseases. To understand the mechanisms of herbal compounds that protect against neurodegenerative diseases, we summarize studies that discovered neuroprotection by herbal compounds and compound-related mechanisms in neurodegenerative disease models. Those compounds discussed herein show neuroprotection through different mechanisms, such as cytokine regulation, autophagy, endoplasmic reticulum (ER) stress, glucose metabolism, and synaptic function. The interleukin (IL)-1β and tumor necrosis factor (TNF)-α signaling pathways are inhibited by some compounds, thus attenuating the inflammatory response and protecting neurons from cell death. As to autophagy regulation, herbal compounds show opposite regulatory effects in different neurodegenerative models. Herbal compounds that inhibit ER stress prevent neuronal death in neurodegenerative diseases. Moreover, there are compounds that protect against neuronal death by affecting glucose metabolism and synaptic function. Since the progression of neurodegenerative diseases is complicated, and compound-related mechanisms for neuroprotection differ, therapeutic strategies may need to involve multiple compounds and consider the type and stage of neurodegenerative diseases.

Thrombopoietin could protect cerebral tissue against ischemia-reperfusion injury by suppressing NF-κB and MMP-9 expression in rats

Objective: To determine the neuroprotective effects and underpinning mechanisms of thrombopoietin (TPO), Matrix Metalloproteinase-9(MMP-9) and Nuclear Factor-κB (NF-κB) after focal cerebral ischemia-reperfusion in rats. Methods: Male rats underwent 2 hours of right middle cerebral artery occlusion (MCAO) followed by 22 hours of reperfusion. PBS or TPO (0.1ug/kg) was administered from caudal vein before reperfusion. Neurologic deficits, brain edema, Evans blue (EB) extravasation, NF-κB and MMP-9 expression were subsequently examined. Results: Ischemia-reperfusion injury produced a large area of edema. TPO significantly reduced edema and alleviated neurologic deficits after ischemia-reperfusion. Ischemia-induced increases of NF-κB, MMP-9 and Evans blue extravasation were reduced by TPO intervention. Conclusion: TPO improved neurological function and ameliorated brain edema after stroke, partly by reducing the ischemia-induced increase of NF-κB and MMP-9.

A Novel Fluoroimmunoassay for Detecting Ruscogenin with Monoclonal Antibodies Conjugated with CdSe/ZnS Quantum Dots

Ruscogenin (RUS) is a steroidal sapogenin found in Ruscus aculeatus and Ophiopogon japonicus with several pharmacological activities. In the work reported herein, a novel method termed competitive fluorescence-linked immunosorbent assay (cFLISA) based on monoclonal antibodies (mAbs) coupled with quantum dots (QDs) was developed for the quick and sensitive determination of RUS in biological samples. The mAbs against RUS were conjugated with CdSe/ZnS QDs by the crossing-linking reagents and an indirect cFLISA method was developed. There was a good linear relationship between inhibition efficiency and logarithm concentration of RUS which was varied from 0.1 to 1000 ng/mL. The IC₅₀ and limit of detection (LOD) were 9.59 ng/mL and 0.016 ng/mL respectively, which much lower than the enzyme-linked immunosorbent assay (ELISA) method. The recoveries in plasma and tissues were ranged from 82.3% to 107.0% and the intra- and inter-day precision values were below 15%. The developed cFLISA has been successfully applied to the measurement of the concentrations of RUS in biological samples of rats, and showed great potential for the tissue distribution study of RUS. The cFLISA method may provide a valuable tool for the analysis of small molecules in biological samples and such an approach could be applied to other natural products.

Nobiletin improves propofol-induced neuroprotection via regulating Akt/mTOR and TLR 4/NF-κB signaling in ischemic brain injury in rats

BACKGROUND

Stroke is regarded as one of the main health concerns globally, presenting with high mortality and morbidity rates. Cerebral ischemic damage and infarction are critically associated with stroke. Various mechanisms related to inflammation, oxidative stress and excitotoxicity are found to be involved in ischemic damage. Very short time period for treatment has necessitated in development of more effective neuroprotective agents. Study aimed in investigated the effects of nobiletin on experimentally induced ischemic brain injury and also to assess whether nobiletin potentiated the neuroprotective effects of propofol.

METHODS

Male Sprague-Dawley rats were subjected to ischemia/reperfusion (I/R) injury. Induction of cerebral infarction and I/R was done by middle cerebral artery occlusion (MCAO). Nobiletin (100 or 200mg/kg b.wt.) was intragastrically administered to rats for 9 days before ischemia induction and on the day of induction nobiletin was administered an hour prior. Separate group of rats were post-conditioned with propofol (50mg/kg/h; i.v.) for 30min following 24h of reperfusion.

RESULTS

Propofol post-conditioning either with or without administration of nobiletin prior I/R injury attenuated pulmonary edema, neuronal apoptosis and reduced cerebral infarct volume. Overproduction of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) and nitric oxide following I/R were reduced. Propofol either alone or with prior nobiletin treatment had down-regulated TLR4 and TLR4-mediated NF-κB signaling and caused activation of Akt/mTOR cascade.

CONCLUSION

Propofol post-conditioning either with nobiletin prior I/R injury was found to be more effective than propofol alone, suggesting the positive effects of nobiletin on propofol-mediated anti-inflammatory and neuroprotective effects.

Plumbagin inhibits neuronal apoptosis, intimal hyperplasia and also suppresses TNF-α/NF-κB pathway induced inflammation and matrix metalloproteinase-2/9 expression in rat cerebral ischemia

Cerebral ischemic damage and infarction are well documented in stroke, which is presenting a foremost health concern globally with very high mortality and morbidity rates. Mechanisms that are associated with excitotoxicity, inflammation and oxidative stress are found to be critically involved in ischemic damage. Adverse effects of current therapies are imposing the need in development of neuroprotective agents that are very effective. To explore this we experimentally induced ischemic brain injury and investigated the effects of plumbagin. Induction of cerebral infarction and ischemia-reperfusion (I/R) was done by middle cerebral artery occlusion (MCAO) in Sprague-Dawley rats. Plumbagin (50, 100 or 200 mg/kg b.wt) was intragastrically administered for 9 days before ischemia induction and an hour prior on the day of ischemic insult. Plumbagin treatment attenuated pulmonary edema, neuronal apoptosis and reduced cerebral infarct volume. Cleaved caspase-3 and apoptotic cascade protein expressions were regulated. Overproduction of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) and nitric oxide (NO) following I/R were reduced. Prior plumbagin administration had down-regulated NF-κB signalling and MMP-2 and MMP-9 expression. Overall, the results reveal the potent neuroprotective efficacy of plumbagin against I/R-induced brain injury via effectively modulating apoptotic pathways, MMPs and neuro-inflammatory cascades.

Protection against cerebral infarction by Withaferin A involves inhibition of neuronal apoptosis, activation of PI3K/Akt signaling pathway, and reduced intimal hyperplasia via inhibition of VSMC migration and matrix metalloproteinases

PURPOSE

Stroke is a major public health concern with high rates of morbidity and mortality worldwide. Cerebral ischemia and infarction are commonly associated with stroke. Currently used medications, though effective, are also associated with adverse effects. Development of effective neuroprotective agents with fewer side effects would be of clinical value. We evaluated the effects of Withaferin A (WA), a steroidal lactone derived from the plant Withania somnifera, on experimentally induced cerebral infarction.

MATERIALS AND METHODS

The ability of WA to inhibit neuroapoptosis and modulate vascular smooth muscle cell (VSMC) migration and PI3K/Akt signaling was assessed. Separate groups of Sprague Dawley rats were subjected to cerebral occlusion and reperfused for 24h.

RESULTS

WA treatment (25, 50 or 100mg/kg bodyweight) significantly reduced the infarct area in a carotid ligation model; WA reduced intimal hyperplasia and proliferating cell nuclear antigen (PCNA)-positive cell counts. Western blotting analysis revealed significantly suppressed PI3K/Akt signaling following cerebral ischemia/reperfusion injury. WA supplementation was found to downregulate apoptotic pathway proteins. WA suppressed PTEN and enhanced p-Akt and GSK-3β levels and elevated mTORc1, cyclinD1 and NF-κB p65 expression, suggesting activation of the PI3K/Akt pathway. In vitro studies with PDGF-stimulated A7r5 cells revealed that WA exposure severely downregulated matrix metalloproteinases (MMP)-2 and -9 and inhibited migration of A7r5 cells. Additionally, WA reduced the proliferation of A7r5 cells significantly.

CONCLUSIONS

WA exerted neuroprotective effects by activating the PI3K/Akt pathway, modulating the expression of MMPs, and inhibiting the migration of VSMCs.

The Effect of Dexmedetomidine on Oxidative Stress Response Following Cerebral Ischemia-Reperfusion in Rats and the Expression of Intracellular Adhesion Molecule-1 (ICAM-1) and S100B

Background

Ischemia-reperfusion injury of whole brain involves a complicated pathophysiology mechanism. Dexmedetomidine (Dex) has been shown to have neuro protective functions. This study observed the effect of Dex on serum S100B and cerebral intracellular adhesion molecule-1 (ICAM-1) in a rat model of cerebral ischemia-reperfusion.

Material/Methods

Healthy Sprague Dawley (SD) rats (males, 7 weeks old) were randomly divided into sham, model, and Dex groups (n=20 each). A cerebral ischemia-reperfusion model was prepared by clipping of the bilateral common carotid artery combined with hypotension. Dex (9 μg/kg) was infused intravenously immediately after reperfusion in the Dex group, while the other two groups received an equal volume of saline. Neural defect score (NDS) was measured at 6 hours, 24 hours, and 72 hours after surgery, with pathological observation of brain tissues. ELISA was then used to test serum S100B protein level. Malondialdehyde (MDA) and superoxide dismutase (SOD) were assayed by spectrometry. Nuclear factor-kappa B (NF-κB) and ICAM-1 levels were determined by real-time (RT)-PCR.

Results

Model rats had significant injury in the hippocampal CA1 region as shown by elevated NDS, S100B, and MDA levels, higher NF-κB and ICAM-1 mRNA expression, and lower SOD levels (p<0.05). Dex treatment improved pathological injury, decreased NDS, S100B, and MDA levels, decreased expression of mRNA of NF-κB and ICAM-1, and increased SOD levels.

Conclusions

Dex alleviated ischemia-reperfusion damage to rat brains, and inhibited NF-κB and ICAM-1 expression in brain tissues, possibly via inhibiting oxidative stress and inflammatory response.

The Combination of Three Components Derived from Sheng MaiSan Protects Myocardial Ischemic Diseases and Inhibits Oxidative Stress via Modulating MAPKs and JAK2-STAT3 Signaling Pathways Based on Bioinformatics Approach

GRS is a drug combination of three components including ginsenoside Rb1, ruscogenin and schisandrin. It derived from the well-known TCM formula Sheng MaiSan, a widely used traditional Chinese medicine for the treatment of cardiovascular diseases in clinic. The present study illuminates its underlying mechanisms against myocardial ischemic diseases based on the combined methods of bioinformatic prediction and experimental verification. A protein database was established through constructing the drug-protein network. And the target-pathway interaction network clustered the potential signaling pathways and targets of GRS in treatment of myocardial ischemic diseases. Several target proteins, such as NFKB1, STAT3 and MAPK14, were identified as the candidate key proteins, and MAPKs and JAK-STAT signaling pathway were suggested as the most related pathways, which were in accordance with the gene ontology analysis. Then, the predictive results were further validated and we found that GRS treatment alleviated hypoxia/reoxygenation (H/R)-induced cardiomyocytes injury via suppression of MDA levels and ROS generation, and potential mechanisms might related to the suppression of activation of MAPKs and JAK2-STAT3 signaling pathways. Conclusively, our results offer the evidence that GRS attenuates myocardial ischemia injury via regulating oxidative stress and MAPKs and JAK2-STAT3 signaling pathways, which supplied some new insights for its prevention and treatment of myocardial ischemia diseases.

Cardioprotection by combination of three compounds from ShengMai preparations in mice with myocardial ischemia/reperfusion injury through AMPK activation-mediated mitochondrial fission

GRS is a drug combination of three active components including ginsenoside Rb1, ruscogenin and schisandrin. It derived from the well-known TCM formula ShengMai preparations, a widely used traditional Chinese medicine for the treatment of cardiovascular diseases in clinic. The present study explores the cardioprotective effects of GRS on myocardial ischemia/reperfusion (MI/R) injury compared with ShengMai preparations and investigates the underlying mechanisms. GRS treatment significantly attenuated MI/R injury and exhibited similar efficacy as Shengmai preparations, as evidenced by decreased myocardium infarct size, ameliorated histological features, the decrease of LDH production and improved cardiac function, and also produced a significant decrease of apoptotic index. Mechanistically, GRS alleviated myocardial apoptosis by inhibiting the mitochondrial mediated apoptosis pathway as reflected by inhibition of caspase-3 activity, normalization of Bcl-2/Bax levels and improved mitochondrial function. Moreover, GRS prevented cardiomyocytes mitochondrial fission and upregulated AMPKα phosphorylation. Interestingly, AMPK activation prevented hypoxia and reoxygenation induced mitochondrial fission in cardiomyocytes and GRS actions were significantly attenuated by knockdown of AMPKα. Collectively, these data show that GRS is effective in mitigating MI/R injury by suppressing mitochondrial mediated apoptosis and modulating AMPK activation-mediated mitochondrial fission, thereby providing a rationale for future clinical applications and potential therapeutic strategy for MI/R injury.

Inhibition of HSP90 Promotes Neural Stem Cell Survival from Oxidative Stress through Attenuating NF-κB/p65 Activation

Stem cell survival after transplantation determines the efficiency of stem cell treatment, which develops as a novel potential therapy for several central nervous system (CNS) diseases in recent decades. The engrafted stem cells face the damage of oxidative stress, inflammation, and immune response at the lesion point in host. Among the damaging pathologies, oxidative stress directs stem cells to apoptosis and even death through several signalling pathways and DNA damage. However, the in-detail mechanism of stem cell survival from oxidative stress has not been revealed clearly. Here, in this study, we used hydrogen peroxide (H₂O₂) to induce the oxidative damage on neural stem cells (NSCs). The damage was in consequence demonstrated involving the activation of heat shock protein 90 (HSP90) and NF-κB/p65 signalling pathways. Further application of the pharmacological inhibitors, respectively, targeting at each signalling indicated an upper-stream role of HSP90 upon NF-κB/p65 on NSCs survival. Preinhibition of HSP90 with the specific inhibitor displayed a significant protection on NSCs against oxidative stress. In conclusion, inhibition of HSP90 would attenuate NF-κB/p65 activation by oxidative induction and promote NSCs survival from oxidative damage. The HSP90/NF-κB mechanism provides a new evidence on rescuing NSCs from oxidative stress and also promotes the stem cell application on CNS pathologies.

Anti-Inflammatory Effects of Traditional Chinese Medicines against Ischemic Injury in In Vivo Models of Cerebral Ischemia

Inflammation plays a crucial role in the pathophysiology of acute ischemic stroke. In the ischemic cascade, resident microglia are rapidly activated in the brain parenchyma and subsequently trigger inflammatory mediator release, which facilitates leukocyte-endothelial cell interactions in inflammation. Activated leukocytes invade the endothelial cell junctions and destroy the blood-brain barrier integrity, leading to brain edema. Toll-like receptors (TLRs) stimulation in microglia/macrophages through the activation of intercellular signaling pathways secretes various proinflammatory cytokines and enzymes and then aggravates cerebral ischemic injury. The secreted cytokines activate the proinflammatory transcription factors, which subsequently regulate cytokine expression, leading to the amplification of the inflammatory response and exacerbation of the secondary brain injury. Traditional Chinese medicines (TCMs), including TCM-derived active compounds, Chinese herbs, and TCM formulations, exert neuroprotective effects against inflammatory responses by downregulating the following: ischemia-induced microglial activation, microglia/macrophage-mediated cytokine production, proinflammatory enzyme production, intercellular adhesion molecule-1, matrix metalloproteinases, TLR expression, and deleterious transcription factor activation. TCMs also aid in upregulating anti-inflammatory cytokine expression and neuroprotective transcription factor activation in the ischemic lesion in the inflammatory cascade during the acute phase of cerebral ischemia. Thus, TCMs exert potent anti-inflammatory properties in ischemic stroke and warrant further investigation.

Ruscogenin Attenuates Cerebral Ischemia-Induced Blood-Brain Barrier Dysfunction by Suppressing TXNIP/NLRP3 Inflammasome Activation and the MAPK Pathway

Ruscogenin, an important steroid sapogenin derived from Ophiopogon japonicus, has been shown to inhibit cerebral ischemic injury. However, its potential molecular action on blood-brain barrier (BBB) dysfunction after stroke remains unclear. This study aimed to investigate the effects of ruscogenin on BBB dysfunction and the underlying mechanisms in middle cerebral artery occlusion/reperfusion (MCAO/R)-injured mice and oxygen–glucose deprivation/reoxygenation (OGD/R)-injured mouse brain microvascular endothelial cells (bEnd.3). The results demonstrated that administration of ruscogenin (10 mg/kg) decreased the brain infarction and edema, improved neurological deficits, increased cerebral brain flow (CBF), ameliorated histopathological damage, reduced evans blue (EB) leakage and upregulated the expression of tight junctions (TJs) in MCAO/R-injured mice. Meanwhile, ruscogenin (0.1–10 µM) treatment increased cell viability and trans-endothelial electrical resistance (TEER) value, decreased sodium fluorescein leakage, and modulated the TJs expression in OGD/R-induced bEnd.3 cells. Moreover, ruscogenin also inhibited the expression of interleukin-1β (IL-1β) and caspase-1, and markedly suppressed the expression of Nucleotide-binding domain (NOD)-like receptor family, pyrin domain containing 3 (NLRP3) and thiredoxin-interactive protein (TXNIP) in vivo and in vitro. Furthermore, ruscogenin decreased reactive oxygen species (ROS) generation and inhibited the mitogen-activated protein kinase (MAPK) pathway in OGD/R-induced bEnd.3 cells. Our findings provide some new insights into its potential application for the prevention and treatment of ischemic stroke.

Phytochemicals in Ischemic Stroke

Stroke is the second foremost cause of mortality worldwide and a major cause of long-term disability. Due to changes in lifestyle and an aging population, the incidence of stroke continues to increase and stroke mortality predicted to exceed 12 % by the year 2030. However, the development of pharmacological treatments for stroke has failed to progress much in over 20 years since the introduction of the thrombolytic drug, recombinant tissue plasminogen activator. These alarming circumstances caused many research groups to search for alternative treatments in the form of neuroprotectants. Here, we consider the potential use of phytochemicals in the treatment of stroke. Their historical use in traditional medicine and their excellent safety profile make phytochemicals attractive for the development of therapeutics in human diseases. Emerging findings suggest that some phytochemicals have the ability to target multiple pathophysiological processes involved in stroke including oxidative stress, inflammation and apoptotic cell death. Furthermore, epidemiological studies suggest that the consumption of plant sources rich in phytochemicals may reduce stroke risk, and so reinforce the possibility of developing preventative or neuroprotectant therapies for stroke. In this review, we describe results of preclinical studies that demonstrate beneficial effects of phytochemicals in experimental models relevant to stroke pathogenesis, and we consider their possible mechanisms of action.

YiQiFuMai Powder Injection ameliorates the oxygen-glucose deprivation-induced brain microvascular endothelial barrier dysfunction associated with the NF-κB and ROCK1/MLC signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

YiQiFuMai Powder Injection (YQFM) is a modern preparation derived from Sheng-mai San, a traditional Chinese prescription, widely used for the treatment of cardiovascular and cerebrovascular diseases. However, its potential molecular mechanism remains unclear.

AIM OF THE STUDY

The present study was designed to observe the effect of YQFM on oxygen-glucose deprivation (OGD)-induced the brain microvascular endothelial barrier dysfunction and to explore the underlying pathways in vitro.

METHODS

A mouse brain microvascular endothelial cell line (bEnd.3) was subjected to OGD (2-9h) to examine the efficacy and molecular mechanisms in the presence or absence of YQFM (100, 200 and 400 μg/ml).

RESULTS

The results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Trans-endothelial electrical resistance (TEER) assays demonstrated that treatment with YQFM increased the cell viability and TEER value, decreased even blue (EB) albumin leakage after OGD in bEnd.3 cells. Western blotting and immunofluorescence staining showed that YQFM reduced the breakage and translocation of Zonula occludens-1 (ZO-1) and claudin-5 after 4h of OGD and decreased the expression of these proteins after 9h of OGD. Moreover, YQFM significantly inhibited the expression, phosphorylation and nuclear translocation of NF-κB/p65 and decreased the expression of intercellular adhesionmolecule-1 (ICAM-1) and cyclooxygenase (COX-2) as well as production of nitric oxide (NO). In addition, real time-PCR results revealed that YQFM suppressed the mRNA levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) after 4h of OGD. Furthermore, YQFM markedly inhibited both the phosphorylation of myosin light chain (MLC) and cytoskeletal reorganization and reduced the expression of cleaved-ROCK1 in bEnd.3 cells subjected to OGD.

CONCLUSION

These findings suggest that YQFM ameliorates the OGD-induced brain microvascular endothelial cell barrier disruption associated with the NF-κB/p65 and ROCK1/MLC signaling pathways. These data provide new insights into the use of this preparation for treating cerebrovascular diseases.

Ophiopogon japonicus--A phytochemical, ethnomedicinal and pharmacological review

ETHNOPHARMACOLOGICAL RELEVANCE

Ophiopogonis Radix (Maidong in Chinese), the root of Ophiopogon japonicus, is widely used in local medicines of China, Japan and some south-eastern Asian countries. According to the traditional Chinese medicine (TCM) principle, Ophiopogonis Radix nourishes the yin, promotes body fluid production, moistens the lung, eases the mind and clears away heart fire. This review summarizes the achievements of the investigations in botany, phytochemistry, quality control, traditional uses, pharmacological activities and clinical studies on O. japonicus; this review also describes the shortcomings of studies on this herbal drug and thus serves as the basis of further scientific research and development of this traditional herbal drug.

MATERIALS AND METHODS

O. japonicus-related information was collected from various resources, including books on Chinese herbs and the Internet databases, such as Google Scholar, SciFinder, Web of Science, Elsevier, ACS, PubMed and China Knowledge Resource Integrated (CNKI).

RESULTS

O. japonicus is widely distributed in East Asia, especially in China. Numerous compounds were identified from this plant. The main components of O. japonicus include steroidal saponins, homoisoflavonoids and polysaccharides, which exhibited various pharmacological activities, such as cardiovascular protection, anti-inflammation, anticancer, anti-oxidation, immunomodulation, cough relief, antimicrobial, and anti-diabetes.

CONCLUSIONS

O. japonicus is a common traditional Chinese herbal drug used as the main ingredient in many prescriptions. Modern researches verified that O. japonicus can be used either as a healthy food or a therapeutic agent for disease prevention and treatment. The molecular mechanisms and chemical principles of this herbal medicine should be further explored.