Harpagide from Scrophularia protects rat cortical neurons from oxygen-glucose deprivation and reoxygenation-induced injury by decreasing endoplasmic reticulum stress

Substance basis and pharmacological mechanism of heat-clearing herbs in the treatment of ischaemic encephalopathy: a systematic review and network pharmacology

BACKGROUND AND OBJECTIVE

Ischaemic encephalopathy is a common cerebrovascular disease caused by insufficient blood supply to the cerebral vessels. The ischaemic encephalopathy is closely associated with the development of many chronic diseases such as obesity, hypertension and diabetes. Neurotrophic therapy has become the main therapeutic strategy for ischaemic encephalopathy. However, neurotrophic drugs only slightly recover the neurological function of patients, and their long-term efficacy is uncertain. Previous reports revealed that the active ingredients of natural medicines play important roles in the treatment of cerebral ischemia. In this study, we reviewed clearing herbs with anti-ischaemic encephalopathy functions using the data from quantitative statistical and network pharmacological exploration methods. We also discussed the different bioactive components and pharmacological effects of these herbs.

METHODS

First, we collected Chinese herbal prescriptions against ischaemic encephalopathy in four databases. Then, we statistically analysed the frequency of application of heat-clearing herbs to obtain the commonly used heat-clearing herbs against ischaemic encephalopathy, and classified them according to their efficacy according to the statistical results, to summarize the mechanism of anti-ischaemic effects of different bioactive components; Second, the network database was used to obtain the above components of heat-clearing Chinese medicines and their corresponding targets of action, disease targets of ischaemic stroke; Venny 2.1.0 was used to obtain component-disease target intersections; Cytoscape was used to construct the 'Drug-Active Ingredient-Target Network Graph '; DAVID was used for GO and KEGG enrichment analysis.

RESULTS

Literature and database screening involved 149 prescriptions, with a total of 269 flavours of Chinese medicines and 20 flavours of single-flavour heat-clearing Chinese medicines; The top nine in terms of frequency of use were Radix Paeoniae Rubra、Rehmanniae Radix Praeparata、Figwort Root、Cortex Moutan、Scutellariae Radix、Coptidis Rhizoma、Gardeniae Fructus、Cassiae Semen、Lonicerae Japonicae Flos. The common components obtained from network pharmacology were beta-sitosterol, quercetin, and stigmasterol, which mainly act on key targets such as RELA, AKT1, JUN, PRKACA, PTGS2, RAF1 and CHUK; and their active ingredients are mainly involved in signalling pathways such as Calcium, PI3K-Ak, MAPK, cAMP, IL-17, HIF-1, TNF, T-cell receptor, NF-kappa B and JAK-STAT.

CONCLUSIONS

Heat-clearing herbs are useful and promising for the protection against and prevention of ischemic encephalopathy. The results of the network pharmacological studies are similar to the mechanisms of anti-ischemic encephalopathy of the active ingredients of the purgative herbs we have listed; Thin either directly protects cerebrovascular tissues by improving vascular permeability and reducing the area of infarcted tissues, or produces protective effects through molecular signaling pathways. It can be seen that the components of heat-clearing Chinese medicines can exert cerebroprotective effects through multiple pathways, which provides us with a reference for further development and study of heat-clearing Chinese medicines in the treatment of ischemic cerebrovascular diseases.

Ischemia-reperfusion injury: molecular mechanisms and therapeutic targets

Ischemia-reperfusion (I/R) injury paradoxically occurs during reperfusion following ischemia, exacerbating the initial tissue damage. The limited understanding of the intricate mechanisms underlying I/R injury hinders the development of effective therapeutic interventions. The Wnt signaling pathway exhibits extensive crosstalk with various other pathways, forming a network system of signaling pathways involved in I/R injury. This review article elucidates the underlying mechanisms involved in Wnt signaling, as well as the complex interplay between Wnt and other pathways, including Notch, phosphatidylinositol 3-kinase/protein kinase B, transforming growth factor-β, nuclear factor kappa, bone morphogenetic protein, N-methyl-D-aspartic acid receptor-Ca2+-Activin A, Hippo-Yes-associated protein, toll-like receptor 4/toll-interleukine-1 receptor domain-containing adapter-inducing interferon-β, and hepatocyte growth factor/mesenchymal-epithelial transition factor. In particular, we delve into their respective contributions to key pathological processes, including apoptosis, the inflammatory response, oxidative stress, extracellular matrix remodeling, angiogenesis, cell hypertrophy, fibrosis, ferroptosis, neurogenesis, and blood-brain barrier damage during I/R injury. Our comprehensive analysis of the mechanisms involved in Wnt signaling during I/R reveals that activation of the canonical Wnt pathway promotes organ recovery, while activation of the non-canonical Wnt pathways exacerbates injury. Moreover, we explore novel therapeutic approaches based on these mechanistic findings, incorporating evidence from animal experiments, current standards, and clinical trials. The objective of this review is to provide deeper insights into the roles of Wnt and its crosstalk signaling pathways in I/R-mediated processes and organ dysfunction, to facilitate the development of innovative therapeutic agents for I/R injury.

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

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

Therapeutic targets by traditional Chinese medicine for ischemia-reperfusion injury induced apoptosis on cardiovascular and cerebrovascular diseases

Traditional Chinese medicine (TCM) has a significant role in treating and preventing human diseases. Ischemic heart and cerebrovascular injuries are two types of diseases with different clinical manifestations with high prevalence and incidence. In recent years, it has been reported that many TCM has beneficial effects on ischemic diseases through the inhibition of apoptosis, which is the key target to treat myocardial and cerebral ischemia. This review provides a comprehensive summary of the mechanisms of various TCMs in treating ischemic cardiovascular and cerebrovascular diseases through anti-apoptotic targets and pathways. However, clinical investigations into elucidating the pharmacodynamic ingredients of TCM are still lacking, which should be further demystified in the future. Overall, the inhibition of apoptosis by TCM may be an effective strategy for treating ischemic cardio-cerebrovascular diseases.

Harpagide alleviate neuronal apoptosis and blood-brain barrier leakage by inhibiting TLR4/MyD88/NF-κB signaling pathway in Angiotensin II-induced microglial activation in vitro

Angiotensin II, the effector peptide of the renin-angiotensin system, is not only a pivotal peptide implicated in the regulation of blood pressure but also a key mediator of the inflammatory processes that play an important role in the pathology of hypertension-related cSVD. Harpagide is the major bioactive constituent of Scrophulariae Radix widely used in traditional Chinese medicine for numerous diseases including hypertension. The present study aimed to investigate the effect of harpagide on Ang II-induced neuroinflammation and the potential mechanism. Pretreated with harpagide or resatorvid (the TLR4 pathway inhibitor), BV2 cells were treated with Ang II or LPS (the TLR4 activator). NO, pro-inflammatory cytokines, the proteins on TLR4/MyD88/NF-κB signaling pathway and the expression of CD86, CD206, TREM2 in BV2 cells were detected respectively. Subsequently, the effects of harpagide on neurotoxicity and BBB destruction triggered by Ang II-induced neuroinflammation were investigated in the co-cultures of BV2 microglia/HT22 hippocampal neurons, BV2 microglia/bEnd.3 endotheliocyte and BV2 microglia/BBB monolayer model. We found that Ang II converted microglia into M1 state and resulted in neuroinflammation through activating TLR4/MyD88/NF-κB signaling pathway. It also triggered the imbalance of TLR4/TREM2 in microglia. Ang II-mediated inflammation microglia further led to neuronal apoptosis and BBB damage. Harpagide showed the effect of alleviating Ang II-mediated neuroinflammation as well as the resulting neurotoxicity and BBB destruction through inhibiting the TLR4/MyD88/NF-κB pathway. The anti-inflammatory and neuroprotective effect of harpagide suggested that it might be a potential therapeutic strategy in hypertensive cSVD.

CTRP1 Attenuates Cerebral Ischemia/Reperfusion Injury via the PERK Signaling Pathway

Cerebral ischemic stroke is one of the leading causes of death worldwide. Previous studies have shown that circulating levels of CTRP1 are upregulated in patients with acute ischemic stroke. However, the function of CTRP1 in neurons remains unclear. The purpose of this study was to explore the role of CTRP1 in cerebral ischemia reperfusion injury (CIRI) and to elucidate the underlying mechanism. Middle cerebral artery occlusion/reperfusion (MCAO/R) and oxygen-glucose deprivation/reoxygenation (OGD/R) models were used to simulate cerebral ischemic stroke in vivo and in vitro, respectively. CTRP1 overexpression lentivirus and CTRP1 siRNA were used to observe the effect of CTRP1 expression, and the PERK selective activator CCT020312 was used to activate the PERK signaling pathway. We found the decreased expression of CTRP1 in the cortex of MCAO/R-treated rats and OGD/R-treated primary cortical neurons. CTRP1 overexpression attenuated CIRI, accompanied by the reduction of apoptosis and suppression of the PERK signaling pathway. Interference with CTRP1 expression in vitro aggravated apoptotic activity and increased the expression of proteins involved in the PERK signaling pathway. Moreover, activating the PERK signaling pathway abolished the protective effects of CTRP1 on neuron injury induced by CIRI in vivo and in vitro. In conclusion, CTRP1 protects against CIRI by reducing apoptosis and endoplasmic reticulum stress (ERS) through inhibiting the PERK-dependent signaling pathway, suggesting that CTRP1 plays a crucial role in the pathogenesis of CIRI.

Pharmacology, phytochemistry, and traditional uses of Scrophularia ningpoensis Hemsl

ETHNOPHARMACOLOGICAL RELEVANCE

Scrophularia ningpoensis Hemsl. (known as Xuanshen) has been used in China for centuries as a traditional medicinal plant to treat numerous diseases including inflammation, hypertension, cancer, and diabetes.

AIM OF REVIEW

In this review, we provide an update on the botany, pharmacology, phytochemistry, pharmacokinetics, traditional uses, and safety of S. ningpoensis to highlight future research needs and potential uses of this plant.

MATERIALS AND METHODS

All information on S. ningpoensis was obtained from scientific databases including ScienceDirect, Springer, PubMed, Sci Finder, China Knowledge Resource Integrated Database from the China National Knowledge Infrastructure (CNKI), Google Scholar, and Baidu Scholar. Additional information was collected from Chinese herbal medicine books, Ph.D. dissertations, and M.Sc. Theses. Plant taxonomy was verified by "The Plant List" database (http://www.theplantlist.org).

RESULTS

S. ningpoensis displays fever reducing, detoxifying, and nourishing 'Yin' effects in traditional Chinese medicine (TCM). More than 162 compounds have been identified and isolated from S. ningpoensis, including iridoids and iridoid glycosides, phenylpropanoid glycosides, organic acids, volatile oils, terpenoids, saccharides, flavonoids, sterols, and saponins. These compounds possess a diverse variety of pharmacological properties that affect the cardiovascular, hepatic, and nervous systems, and protect the body against inflammation, oxidation, and carcinogenesis.

CONCLUSIONS

Modern pharmacological studies have confirmed that S. ningpoensis is a valuable Chinese medicinal herb with many pharmacological uses in the treatment of cardiovascular, diabetic, and liver diseases. Most of the S. ningpoensis activity may be attributed to iridoid glycosides and phenylpropanoid glycosides; however, detailed information on the molecular mechanisms, metabolic activity, toxicology, and structure-function relationships of active components is limited. Further comprehensive research to evaluate the medicinal properties of S. ningpoensis is needed.

Harpagide exerts a neuroprotective effect by inhibiting endoplasmic reticulum stress via SERCA following oxygen-glucose deprivation/reoxygenation injury

Cerebrovascular diseases endanger human health, and the physiological and pathological processes of cerebral ischemia/reperfusion injury (CIRI) are critical for the occurrence of these diseases and as targets for their treatment. Here, we evaluated the effects of harpagide-mediated pharmacological and genetic inhibition of sarco-endoplasmic reticulum Ca²⁺-ATPase (SERCA) in vitro in PC12 cells. The molecular mechanism by which harpagide protects PC12 cells against oxygen-glucose deprivation/reoxygenation (OGD/R) injury was investigated by evaluating the cell survival rate with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, assessing apoptosis by flow cytometry, determining the intracellular Ca²⁺ concentration ([Ca²⁺]_i) by laser scanning confocal microscopy (LSCM), and measuring the expression of proteins related to SERCA and endoplasmic reticulum stress (ERS) by Western blotting. The results revealed that harpagide significantly decreased thapsigargin (TG)-induced apoptosis of PC12 cells, downregulated the expression of ERS-related markers, considerably improved the TG-induced expression of SERCA-related proteins and reduced the [Ca²⁺]_i, suggesting that harpagide effectively inhibited ERS directly. Moreover, harpagide did not significantly reduce OGD/R-induced apoptosis but increased the expression of ERS markers in PC12/SERCA^- cells, indicating that harpagide targets SERCA to protect against CIRI by suppressing ERS-mediated apoptosis.

Scrophularia ningpoensis Hemsl: a review of its phytochemistry, pharmacology, quality control and pharmacokinetics

OBJECTIVES

Scrophularia ningpoensis Hemsl (SNH) is a commonly used medicinal plant in East Asia. Scrophulariae Radix (SR) is the dried roots of SNH, and is one of the most commonly used medicinal parts of SNH, and is an essential traditional medicine and widely used in East Asia for more than 2000 years. SR is used for clearing away heat and cooling blood, nourishing Yin and reducing fire, detoxicating and resolving a mass. The purpose of this paper is to systematically review the phytochemistry, pharmacology, quality control and pharmacokinetics of SNH based on the surveyed and summarized literature.

KEY FINDINGS

Up to now, iridoids, phenolic glycosides, phenolic acids, alkaloids, flavonoids, triterpenes and other compounds have been isolated and identified from SNH. The extract and chemical components of SNH exerts multiple pharmacological effects, such as hepatoprotective effect, anti-inflammatory effect, neuroprotective effect, anti-ventricular remodeling effect and other activities. Various methods have been developed for the quality control of SNH, mainly for SR. Some bioactive compounds in SNH exhibited different pharmacokinetic behaviours and individual metabolic transformation profiles.

SUMMARY

This review will contribute to understanding the correlation between the pharmacological activities and the traditional usage of SNH, and useful to rational use and drug development in the future.

Biochanin A Alleviates Cerebral Ischemia/Reperfusion Injury by Suppressing Endoplasmic Reticulum Stress-Induced Apoptosis and p38MAPK Signaling Pathway In Vivo and In Vitro

We have previously shown that biochanin A exhibits neuroprotective properties in the context of cerebral ischemia/reperfusion (I/R) injury. The mechanistic basis for such properties, however, remains poorly understood. This study was therefore designed to explore the manner whereby biochanin A controls endoplasmic reticulum (ER) stress, apoptosis, and inflammation within fetal rat primary cortical neurons in response to oxygen-glucose deprivation/reoxygenation (OGD/R) injury, and in a rat model of middle cerebral artery occlusion and reperfusion (MCAO/R) injury. For the OGD/R in vitro model system, cells were evaluated after a 2 h OGD following a 24 h reoxygenation period, whereas in vivo neurological deficits were evaluated following 2 h of ischemia and 24 h of reperfusion. The expression of proteins associated with apoptosis, ER stress (ERS), and p38 MAPK phosphorylation was evaluated in these samples. Rats treated with biochanin A exhibited reduced neurological deficits relative to control rats following MCAO/R injury. Additionally, GRP78 and CHOP levels rose following I/R modeling both in vitro and in vivo, whereas biochanin A treatment was associated with reductions in CHOP levels but further increases in GRP78 levels. In addition, OGD/R or MCAO/R were associated with markedly enhanced p38 MAPK phosphorylation that was alleviated by biochanin A treatment. Similarly, OGD/R or MCAO/R injury resulted in increases in caspase-3, caspase-12, and Bax levels as well as decreases in Bcl-2 levels, whereas biochanin A treatment was sufficient to reverse these phenotypes. Together, these findings thus demonstrate that biochanin A can alleviate cerebral I/R-induced damage at least in part via suppressing apoptosis, ER stress, and p38 MAPK signaling, thereby serving as a potent neuroprotective agent.

Neuroprotection Effect of Astragaloside IV from 2-DG-Induced Endoplasmic Reticulum Stress

Objective

Astragaloside IV shows neuroprotective activity, but its mechanism remains unclear. To investigate whether astragaloside IV protects from endoplasmic reticulum stress (ERS), we focus on the regulation of glycogen synthase kinase-3β (GSK-3β) and mitochondrial permeability transition pore (mPTP) by astragaloside IV in neuronal cell PC12.

Methods and Results

PC12 cells treated with different concentrations of ERS inductor 2-deoxyglucose (2-DG) (25-500 μM) showed a significant increase of glucose-regulated protein 78 (GRP 78) and GRP 94 expressions and a decrease of tetramethylrhodamine ethyl ester (TMRE) fluorescence intensity and mitochondrial membrane potential (∆Ψm), with the peak effect seen at 50 μM, indicating that 2-DG induces ERS and the mPTP opening. Similarly, 50 μM of astragaloside IV increased the GSK-3β phosphorylation at Ser9 most significantly. Next, we examined the neuroprotection of astragaloside IV by dividing the PC12 cells into control group, 2-DG treatment group, astragaloside IV plus 2-DG treatment group, and astragaloside IV only group. PC12 cells treated with 50 μM 2-DG for different time courses (0-36 hr) showed a significant increase of Cleaved-Caspase-3 with the peak at 6 hr. 2-DG significantly induced cell apoptosis and increased the green fluorescence intensity of Annexin V-FITC, and these effects were reversed by astragaloside IV. Such a result indicates that astragaloside IV protected neural cell survival from ERS. 2-DG treatment significantly increased the expressions of inositol-requiring ER-to-nucleus signal kinase 1 (IRE1), phosphor-protein kinase R-like ER kinase (p-PERK), but not affect the transcription factor 6 (ATF6) expression. 2-DG treatment significantly decreased the phosphorylation of GSK-3β and significantly reduced the TMRE fluorescence intensity and ∆Ψm, following mPTP open. Astragaloside IV significantly inhibited the above effects caused by 2-DG, except the upregulation of ATF6 protein. Taken together, astragaloside IV significantly inhibited the ERS caused by 2-DG.

Conclusion

Our data suggested that astragaloside IV protects PC12 cells from ERS by inactivation of GSK-3β and preventing the mPTP opening. The GRP 78, GRP 94, IRE1, and PERK signaling pathways but not ATF6 are responsible for GSK-3β inactivation and neuroprotection by astragaloside IV.

Harpagide: Occurrence in plants and biological activities - A review

In this review article, the occurrence of harpagide in the plant kingdom and its associated biological activities are presented and detailed for the first time. The presence of harpagide has been reported in several botanical families within Asteridae, and harpagide has been observed to exert a wide number of biological activities such as cytotoxic, anti-inflammatory, and neuroprotective. These results show how harpagide can be recovered from several natural sources for several pharmacological purposes even if there is a lot to still be studied. Nowadays, the interest is related to its presence in phytomedicines. Threfore, these studies are useful to support and validate the large use of several plants in the folklore medicine.

Isolation of bioactive components with soluble epoxide hydrolase inhibitory activity from Stachys sieboldii MiQ. by ultrasonic-assisted extraction optimized using response surface methodology

Stachys sieboldii MiQ (SSM) is an important food and medicinal herb in Korea, used to improve memory of patients with senile dementia and cardiovascular diseases. However, little information on bioactive components from SSM or standardized extraction methods for these components is available. This study isolated and purified major components from SSM for the first time, and assessed their ability to inhibit soluble epoxide hydrolase (sEH). The results showed that acteoside is the most potent inhibitor of sEH, with an IC₅₀ of 33.5 ± 0.5 μM. Additional active components, including harpagide, tryptophan, and 8-acetate-harpagide, along with acteoside, were tentatively identified using high-performance liquid chromatography photodiode array tandem mass spectrometry (HPLC-PDA-MS/MS) and quantified using an ultraviolet detector at 210 nm. Further, an ultrasonic-assisted extraction technique for extraction of four bioactive compounds in SSM was developed and optimized using response surface methodology (RSM). The optimal extraction conditions were: extraction time, 30.46 minutes; extraction temperature, 67.95 °C, and methanol concentration 53.85%. The prediction model of RSM was validated with laboratory experiments. The similarity between predicted and actual values was 97.84%. The extraction method is thus a rapid, environment-friendly, energy-saving method can be applied to extract bioactive components from SSM in large quantities.

Overexpression of long non-coding RNA SNHG16 against cerebral ischemia-reperfusion injury through miR-106b-5p/LIMK1 axis

Long non-coding RNA (LncRNA) involved in types of physiological insults and diseases via regulating the responses of complex molecular, including cerebral ischemia-reperfusion (I/R) injury. LncRNA SNHG16 played a potential role in ketamine-induced neurotoxicity. In this study, we utilized an in vitro cell model of I/R to examine the specific function and mechanism of LncRNA SNHG16 in oxygen-glucose deprivation and reperfusion (OGD/R) induced SH-SY5Y cells. After in vitro treatment of OGD/R, the lower the SH-SY5Y cell survival, the higher cell the apoptosis and increased caspase-3 activity was observed. Also, OGD/R induced endoplasmic reticulum stress (ERS) through increasing GRP78 and CHOP expressions and down-regulated LncRNA SNHG16 in SH-SY5Y cells. Conversely, LncRNA SNHG16 overexpression promoted OGD/R induced SH-SY5Y cell survival, suppressed its apoptosis, and caspase-3 activity. GRP78 and CHOP expressions were significantly suppressed in LncRNA SNHG16 overexpressing cells. MiR-106b-5p expression was increased and LIMK1 expression was down-regulated in OGD/R induced SH-SY5Y cells, and these effects were reversed by LncRNA SNHG16 overexpression, respectively. Moreover, LIMK1 is a direct target of MiR-106b-5p, and knockdown of LIMK1 reversed the effects of LncRNA SNHG16 on OGD/R-induced SH-SY5Y cells biology. Altogether, these results confirmed an important neuroprotection role of LncRNA SNHG16 in OGD/R induced SH-SY5Y cells injury, and miR-106b-5p/LIMK1 signal axis was involved in the action of LncRNA SNHG16.