Breviscapine confers a neuroprotective efficacy against transient focal cerebral ischemia by attenuating neuronal and astrocytic autophagy in the penumbra

Potential application of natural compounds in ischaemic stroke: Focusing on the mechanisms underlying "lysosomocentric" dysfunction of the autophagy-lysosomal pathway

Ischaemic stroke (IS) is the second leading cause of death and a major cause of disability worldwide. Currently, the clinical management of IS still depends on restoring blood flow via pharmacological thrombolysis or mechanical thrombectomy, with accompanying disadvantages of narrow therapeutic time window and risk of haemorrhagic transformation. Thus, novel pathophysiological mechanisms and targeted therapeutic candidates are urgently needed. The autophagy-lysosomal pathway (ALP), as a dynamic cellular lysosome-based degradative process, has been comprehensively studied in recent decades, including its upstream regulatory mechanisms and its role in mediating neuronal fate after IS. Importantly, increasing evidence has shown that IS can lead to lysosomal dysfunction, such as lysosomal membrane permeabilization, impaired lysosomal acidity, lysosomal storage disorder, and dysfunctional lysosomal ion homeostasis, which are involved in the IS-mediated defects in ALP function. There is tightly regulated crosstalk between transcription factor EB (TFEB), mammalian target of rapamycin (mTOR) and lysosomal function, but their relationship remains to be systematically summarized. Notably, a growing body of evidence emphasizes the benefits of naturally derived compounds in the treatment of IS via modulation of ALP function. However, little is known about the roles of natural compounds as modulators of lysosomes in the treatment of IS. Therefore, in this context, we provide an overview of the current understanding of the mechanisms underlying IS-mediated ALP dysfunction, from a lysosomal perspective. We also provide an update on the effect of natural compounds on IS, according to their chemical structural types, in different experimental stroke models, cerebral regions and cell types, with a primary focus on lysosomes and autophagy initiation. This review aims to highlight the therapeutic potential of natural compounds that target lysosomal and ALP function for IS treatment.

Flavonoids Derived from Chinese Medicine: Potential Neuroprotective Agents

Due to their complex pathological mechanisms, neurodegenerative diseases have brought great challenges to drug development and clinical treatment. Studies have shown that many traditional Chinese medicines have neuroprotective pharmacological activities such as anti-inflammatory and anti-oxidation properties and have certain effects on improving the symptoms of neurodegenerative diseases and delaying disease progression. Flavonoids are the main active components of many traditional Chinese medicines for the treatment of neurodegenerative diseases. These compounds have a wide range of biological activities, including anti-inflammatory, anti-oxidative stress, regulation of autophagy balance, inhibition of apoptosis, and promotion of neuronal regeneration. This paper focuses on the neuroprotective effects of six common flavonoids: quercetin, rutin, luteolin, kaempferol, baicalein, and puerarin. It then systematically reviews their characteristics, mechanisms, and key signaling pathways, summarizes the common characteristics and laws of their neuroprotective effects, and discusses the significance of strengthening the research on the neuroprotective effects of these compounds, aiming to provide reference for more research and drug development of these substances as neuroprotective drugs.

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.

Breviscapine ameliorates autophagy by activating the JAK2/STAT5/BCL2 pathway in a transient cerebral ischemia rat model

Breviscapine (Bre), an extract from Erigeron breviscapus, has been widely used to treat cerebral ischemia but the mechanisms of its neuroprotective effects need to be clarified. The present study investigated whether Bre could alleviate excessive autophagy induced by cerebral ischemia in the rat middle cerebral artery occlusion (MCAO) ischemia model via activating the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 5 (STAT5)/B-cell lymphoma 2 (BCL2) pathway. Rats were randomly divided into 5 groups, i.e. Sham group, MCAO+saline group, MCAO+Bre group, MCAO+DMSO (Dimethyl sulfoxide) group, and MCAO+Bre+AG490 (Tyrphostin AG490, the inhibitor of STAT5) group. The model was established and neuroprotection was evaluated by determining infarct volumes and conducting neurological behavioral tests. Autophagy levels in the infarct penumbra were detected using transmission electron microscopy and Western blotting. The expression of proteins in the JAK2/STAT5/BCL2 pathway was tested by Western blotting. Compared to the MCAO+saline group, the infarct volumes in the MCAO+Bre group were significantly reduced and neurological behavior improved. Breviscapine administration also significantly increased p-JAK2, p-STAT5, and BCL2 expression but decreased autolysosome numbers; it also downregulated Beclin-1 expression and the LC3II/LCI ratio. The JAK2 inhibitor AG490 reversed these effects. These findings indicate that breviscapine can improve neural recovery following ischemia through alleviating excessive autophagy and activation of the JAK2/STAT5/BCL2 axis.

A study on the mechanism of Beclin-1 m6A modification mediated by catalpol in protection against neuronal injury and autophagy following cerebral ischemia

OBJECTIVE

Catalpol (CAT) has various pharmacological activities and plays a protective role in cerebral ischemia. It has been reported that CAT played a protective role in cerebral ischemia by upregulaing NRF1 expression. Bioinformatics analysis reveals that NRF1 can be used as a transcription factor to bind to the histone acetyltransferase KAT2A. However, the role of KAT2A in cerebral ischemia remains to be studied. Therefore, we aimed to investigate the role of CAT in cerebral ischemia and its related mechanism.

METHODS

In vitro, a cell model of oxygen and glucose deprivation/reperfusion (OGD/R) was constructed, followed by evaluation of neuronal injury and the expression of METTL3, Beclin-1, NRF1, and KAT2A. In vivo, a MCAO rat model was prepared by means of focal cerebral ischemia, followed by assessment of neurological deficit and brain injury in MCAO rats. Neuronal autophagy was evaluated by observation of autophagosomes in neurons or brain tissues by TEM and detection of the expression of LC3 and p62.

RESULTS

In vivo, CAT reduced the neurological function deficit and infarct volume, inhibited neuronal apoptosis in the cerebral cortex, and significantly improved neuronal injury and excessive autophagy in MCAO rats. In vitro, CAT restored OGD/R-inhibited cell viability, inhibited cell apoptosis, LDH release, and neuronal autophagy. Mechanistically, CAT upregulated NRF1, NRF1 activated METTL3 via KAT2A transcription, and METTL3 inhibited Beclin-1 via m6A modification.

CONCLUSION

CAT activated the NRF1/KAT2A/METTL3 axis and downregulated Beclin-1 expression, thus relieving neuronal injury and excessive autophagy after cerebral ischemia.

Scutellarin alleviates tensile stress-induced proliferation and migration of venous smooth muscle cells via mediating the p38 MAPK pathway

OBJECTIVE

Abnormal proliferation and migration of biomechanical force-induced venous smooth muscle cells (VSMCs) is a major cause to limit the efficacy of coronary artery bypass grafting (CABG) for coronary heart disease (CHD). Scutellarin is the main active ingredient of Erigeron Breviscapus, and has broad-spectrum pharmacological effects. Therefore, the present study was proposed to investigate the effect of Scutellarin on VSMCs under tensile stress.

METHODS

After interfering with VSMCs at different tensile stresses, the optimal tensile stress was screened. In a tensile stress environment, 100 μM Scutellarin and Hesperetin (p38 MAPK pathway activator) was used to treatment with VSMCs. CCK-8, EDU, Wound healing, flow cytometry and western blotting assays were used to detect cell proliferation, migration, apoptosis, and the expression of apoptosis-related proteins (Caspase3, Bcl2 and Bax).

RESULTS

Tensile stress with 10% significantly enhanced the activity, wound-healing ratio, and EDU+ cells of VSMCs, and decreased their apoptosis ratio. Moreover, it upregulated Bcl2 expression, and downregulated cleaved-Caspase3 and Bax expression of VSMCs. Hence, 10% tensile stress was selected to creates a tensile stress environment for VSMCs. Interestingly, 100 μM Scutellarin alleviated the effect of 10% tensile stress on the phenotype of VSMCs. Notably, 10% tensile stress increased the phosphorylation level of p38 MAPK (Thr180 +Tyr182) in VSMCs, which was restricted by Scutellarin. Further, Hesperetin restored the effect of Scutellarin on the phenotype of VSMCs.

CONCLUSION

Scutellarin alleviates tension stress-induced proliferation and migration of VSMCs via suppressing p38 MAPK pathway. Scutellarin may be used as an adjunctive strategy for future GABG treatment in CHD patients.

Intracerebroventricular BDNF infusion may reduce cerebral ischemia/reperfusion injury by promoting autophagy and suppressing apoptosis

Here, it was aimed to investigate the effects of intracerebroventricular (ICV) Brain Derived Neurotrophic Factor (BDNF) infusion for 7 days following cerebral ischemia (CI) on autophagy in neurons in the penumbra. Focal CI was created by the occlusion of the right middle cerebral artery. A total of 60 rats were used and divided into 4 groups as Control, Sham CI, CI and CI + BDNF. During the 7-day reperfusion period, aCSF (vehicle) was infused to Sham CI and CI groups, and BDNF infusion was administered to the CI + BDNF group via an osmotic minipump. By the end of the 7th day of reperfusion, Beclin-1, LC3, p62 and cleaved caspase-3 protein levels in the penumbra area were evaluated using Western blot and immunofluorescence. BDNF treatment for 7 days reduced the infarct area after CI, induced the autophagic proteins Beclin-1, LC3 and p62 and suppressed the apoptotic protein cleaved caspase-3. Furthermore, rotarod and adhesive removal test times of BDNF treatment started to improve from the 4th day, and the neurological deficit score from the 5th day. ICV BDNF treatment following CI reduced the infarct area by inducing autophagic proteins Beclin-1, LC3 and p62 and inhibiting the apoptotic caspase-3 protein while its beneficial effects were apparent in neurological tests from the 4th day.

Advancements in research on the immune-inflammatory mechanisms mediated by NLRP3 inflammasome in ischemic stroke and the regulatory role of natural plant products

Ischemic stroke (IS) is a major cause of mortality and disability among adults. Recanalization of blood vessels to facilitate timely reperfusion is the primary clinical approach; however, reperfusion itself may trigger cerebral ischemia-reperfusion injury. Emerging evidence strongly implicates the NLRP3 inflammasome as a potential therapeutic target, playing a key role in cerebral ischemia and reperfusion injury. The aberrant expression and function of NLRP3 inflammasome-mediated inflammation in cerebral ischemia have garnered considerable attention as a recent research focus. Accordingly, this review provides a comprehensive summary of the signaling pathways, pathological mechanisms, and intricate interactions involving NLRP3 inflammasomes in cerebral ischemia-reperfusion injury. Moreover, notable progress has been made in investigating the impact of natural plant products (e.g., Proanthocyanidins, methylliensinine, salidroside, α-asarone, acacia, curcumin, morin, ginsenoside Rd, paeoniflorin, breviscapine, sulforaphane, etc.) on regulating cerebral ischemia and reperfusion by modulating the NLRP3 inflammasome and mitigating the release of inflammatory cytokines. These findings aim to present novel insights that could contribute to the prevention and treatment of cerebral ischemia and reperfusion injury.

Novel insight into the therapeutical potential of flavonoids from traditional Chinese medicine against cerebral ischemia/reperfusion injury

Cerebral ischemia/reperfusion injury (CIRI) is a major contributor to poor prognosis of ischemic stroke. Flavonoids are a broad family of plant polyphenols which are abundant in traditional Chinese medicine (TCM) and have beneficial effects on several diseases including ischemic stroke. Accumulating studies have indicated that flavonoids derived from herbal TCM are effective in alleviating CIRI after ischemic stroke in vitro or in vivo, and exhibit favourable therapeutical potential. Herein, we systematically review the classification, metabolic absorption, neuroprotective efficacy, and mechanisms of TCM flavonoids against CIRI. The literature suggest that flavonoids exert potential medicinal functions including suppressing excitotoxicity, Ca2+ overloading, oxidative stress, inflammation, thrombin's cellular toxicity, different types of programmed cell deaths, and protecting the blood-brain barrier, as well as promoting neurogenesis in the recovery stage following ischemic stroke. Furthermore, we identified certain matters that should be taken into account in future research, as well as proposed difficulties and opportunities in transforming TCM-derived flavonoids into medications or functional foods for the treatment or prevention of CIRI. Overall, in this review we aim to provide novel ideas for the identification of new prospective medication candidates for the therapeutic strategy against ischemic stroke.

Breviscapine protects against pathological cardiac hypertrophy by targeting FOXO3a-mitofusin-1 mediated mitochondrial fusion

Forkhead box O3a (FOXO3a)-mediated mitochondrial dysfunction plays a pivotal effect on cardiac hypertrophy and heart failure (HF). However, the role and underlying mechanisms of FOXO3a, regulated by breviscapine (BRE), on mitochondrial function in HF therapy remain unclear. This study reveals that BRE-induced nuclear translocation of FOXO3a facilitates mitofusin-1 (MFN-1)-dependent mitochondrial fusion in cardiac hypertrophy and HF. BRE effectively promotes cardiac function and ameliorates cardiac remodeling in pressure overload-induced mice. In addition, BRE mitigates phenylephrine (PE)-induced cardiac hypertrophy in cardiomyocytes and fibrosis remodeling in fibroblasts by inhibiting ROS production and promoting mitochondrial fusion, respectively. Transcriptomics analysis underscores the close association between the FOXO pathway and the protective effect of BRE against HF, with FOXO3a emerging as a potential target of BRE. BRE potentiates the nuclear translocation of FOXO3a by attenuating its phosphorylation, other than its acetylation in cardiac hypertrophy. Mechanistically, over-expression of FOXO3a significantly inhibits cardiac hypertrophy and mitochondrial injury by promoting MFN-1-mediated mitochondrial fusion. Furthermore, BRE demonstrates its ability to substantially curb cardiac hypertrophy, reduce mitochondrial ROS production, and enhance MFN-1-mediated mitochondrial fusion through a FOXO3a-dependent mechanism. In conclusion, nuclear FOXO3a translocation induced by BRE presents a successful therapeutic avenue for addressing cardiac hypertrophy and HF through promoting MFN-1-dependent mitochondrial fusion.

Lactiplantibacillus plantarum LPJZ-658 Improves Non-Alcoholic Steatohepatitis by Modulating Bile Acid Metabolism and Gut Microbiota in Mice

Non-alcoholic steatohepatitis (NASH) is one of the most prevalent diseases worldwide; it is characterized by hepatic lipid accumulation, inflammation, and progressive fibrosis. Here, a Western diet combined with low-dose weekly carbon tetrachloride was fed to C57BL/6J mice for 12 weeks to build a NASH model to investigate the attenuating effects and possible mechanisms of Lactiplantibacillus plantarum LPJZ-658. Hepatic pathology, lipid profiles, and gene expression were assessed. The metabolomic profiling of the serum was performed. The composition structure of gut microbiota was profiled using 16s rRNA sequencing. The results show that LPJZ-658 treatment significantly attenuated liver injury, steatosis, fibrosis, and inflammation in NASH mice. Metabolic pathway analysis revealed that several pathways, such as purine metabolism, glycerophospholipid metabolism, linoleic acid metabolism, and primary bile acid biosynthesis, were associated with NASH. Notably, we found that treatment with LPJZ-658 regulated the levels of bile acids (BAs) in the serum. Moreover, LPJZ-658 restored NASH-induced gut microbiota dysbiosis. The correlation analysis deduced obvious interactions between BAs and gut microbiota. The current study indicates that LPJZ-658 supplementation protects against NASH progression, which is accompanied by alternating BA metabolic and modulating gut microbiota.

Identification of m6A methylation-related genes in cerebral ischaemia‒reperfusion of Breviscapus therapy based on bioinformatics methods

BACKGROUND

Cerebral ischaemia‒reperfusion (I/R) frequently causes late-onset neuronal damage. Breviscapine promotes autophagy in microvascular endothelial cells in I/R and can inhibit oxidative damage and apoptosis. However, the mediation mechanism of breviscapine on neuronal cell death is unclear.

METHODS

First, transcriptome sequencing was performed on three groups of mice: the neuronal normal group (Control group), the oxygen-glucose deprivation/ reoxygenation group (OGD/R group) and the breviscapine administration group (Therapy group). Differentially expressed genes (DEGs) between the OGD/R and control groups and between the Therapy and OGD/R groups were obtained by the limma package. N6-methyladenosine (m6A) methylation-related DEGs were selected by Pearson correlation analysis. Then, prediction and confirmation of drug targets were performed by Swiss Target Prediction and UniProt Knowledgebase (UniProtKB) database, and key genes were obtained by Pearson correlation analysis between m6A-related DEGs and drug target genes. Next, gene set enrichment analysis (GSEA) and Ingenuity pathway analysis (IPA) were used to obtain the pathways of key genes. Finally, a circRNA-miRNA‒mRNA network was constructed based on the mRNAs, circRNAs and miRNAs.

RESULTS

A total of 2250 DEGs between the OGD/R and control groups and 757 DEGs between the Therapy and OGD/R groups were selected by differential analysis. A total of 7 m6A-related DEGs, including Arl4d, Gm10653, Gm1113, Kcns3, Olfml2a, Stk26 and Tfcp2l1, were obtained by Pearson correlation analysis. Four key genes (Tfcp2l1, Kcns3, Olfml2a and Arl4d) were acquired, and GSEA showed that these key genes significantly participated in DNA repair, e2f targets and the g2m checkpoint. IPA revealed that Tfcp2l1 played a significant role in human embryonic stem cell pluripotency. The circRNA-miRNA‒mRNA network showed that mmu_circ_0001258 regulated Tfcp2l1 by mmu-miR-301b-3p.

CONCLUSIONS

In conclusion, four key genes, Tfcp2l1, Kcns3, Olfml2a and Arl4d, significantly associated with the treatment of OGD/R by breviscapine were identified, which provides a theoretical basis for clinical trials.

Melatonin Attenuates Cerebral Ischemia/Reperfusion Injury through Inducing Autophagy

INTRODUCTION

The aim of this study was to investigate how melatonin administration for 3 days or 7 days following cerebral ischemia (CI) injury would affect autophagy and, therefore, survival in neurons of the penumbra region. Moreover, it was also aimed at determining how this melatonin treatment would affect the neurological deficit score and rotarod and adhesive removal test durations.

METHODS

Focal CI (90 min) was achieved in a total of 105 rats utilizing a middle cerebral artery occlusion model. After the start of reperfusion, the groups were treated with melatonin (10 mg/kg/day) for 3 days or 7 days. In all groups, neurological deficit scoring, rotarod, and adhesive removal tests were executed during reperfusion. Infarct areas were determined by TTC (2,3,5-triphenyltetrazolium chloride) staining at the end of the 3rd and 7th days of reperfusion. Beclin-1, LC3, p62, and caspase-3 protein levels were assessed using Western blot and immunofluorescence methods in the brain tissues. Moreover, penumbra areas were evaluated by transmission electron microscopy (TEM).

RESULTS

Following CI, it was observed that melatonin treatment improved the rotarod and adhesive removal test durations from day 5 and reduced the infarct area after CI. It also induced autophagic proteins Beclin-1, LC3, and p62 and suppressed the apoptotic protein cleaved caspase-3. According to TEM findings, melatonin treatment partially reduced the damage in neurons after CI.

CONCLUSION

Melatonin treatment following CI reduced the infarct area and induced the autophagic proteins Beclin-1, LC3, and p62 by inhibiting the apoptotic caspase-3 protein. The functional reflection of melatonin treatment on neurological test scores was became significant from the 5th day onward.

Anti-Angiogenic Effects of Natural Compounds in Diet-Associated Hepatic Inflammation

Alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD) are the most common causes of chronic liver disease and are increasingly emerging as a global health problem. Such disorders can lead to liver damage, resulting in the release of pro-inflammatory cytokines and the activation of infiltrating immune cells. These are some of the common features of ALD progression in ASH (alcoholic steatohepatitis) and NAFLD to NASH (non-alcoholic steatohepatitis). Hepatic steatosis, followed by fibrosis, lead to a continuous progression accompanied by angiogenesis. This process creates hypoxia, which activates vascular factors, initiating pathological angiogenesis and further fibrosis. This forms a vicious cycle of ongoing damage and progression. This condition further exacerbates liver injury and may contribute to the development of comorbidities, such as metabolic syndrome as well as hepatocellular carcinoma. Increasing evidence suggests that anti-angiogenic therapy may have beneficial effects on these hepatic disorders and their exacerbation. Therefore, there is a great interest to deepen the knowledge of the molecular mechanisms of natural anti-angiogenic products that could both prevent and control liver diseases. In this review, we focus on the role of major natural anti-angiogenic compounds against steatohepatitis and determine their potential therapeutic benefits in the treatment of liver inflammation caused by an imbalanced diet.

Liensinine ameliorates ischemia-reperfusion-induced brain injury by inhibiting autophagy via PI3K/AKT signaling

The current study aimed to explore the role of autophagy in cerebral ischemia-reperfusion injuries (CIRI) and elucidate the efficacy of liensinine treatment. An in vitro ischemia-reperfusion (I/R) neuronal cell model was established and pretreated with liensinine or rapamycin (RAPA). Cell proliferation and survival were detected using a cell counting kit-8 (CCK-8) assay, while cell damage and apoptosis were detected using the lactate dehydrogenase (LDH) leakage rate and flow cytometry. Autophagy activity was detected using monodansylcadaverine (MDC) staining. Thereafter, I/R models were established in vivo in rats and the presence of neurological deficits was examined. Hematoxylin-eosin (HE) and triphenyl tetrazolium chloride (TTC) staining was used to detect pathological damage in brain tissue and the volume ratio of the cerebral infarction. The levels of PI3K/AKT pathway-related proteins and autophagy-related proteins (mTOR, LC3, P62, and TSC2) were detected using Western blot. The findings showed that liensinine treatment increased cell viability, decreased cell injury and apoptosis, and inhibited autophagy. The addition of RAPA to promote autophagy inhibited cell viability and enhanced cell injury and apoptosis. The I/R rats in the model group exhibited deficient neurological function, while those in the liensinine treatment group showed restoration of normal neural function and reduction of the necrotic area and infarct volume ratio in the brain tissue. Furthermore, liensinine treatment also inhibited the PI3K/Akt pathway activity and autophagy. However, addition of RAPA reversed the effects of liensinine treatment and aggravated brain tissue injury. Therefore, liensinine can play a neuroprotective role in CIRI by inhibiting autophagy through regulation of the PI3K/Akt pathway.

Rapid and Efficient Optimization Method for a Genetic Transformation System of Medicinal Plants Erigeron breviscapus

Erigeron breviscapus is an important medicinal plant with high medicinal and economic value. It is currently the best natural biological drug for the treatment of obliterative cerebrovascular disease and the sequela of cerebral hemorrhage. Therefore, to solve the contradiction between supply and demand, the study of genetic transformation of E. breviscapus is essential for targeted breeding. However, establishing an efficient genetic transformation system is a lengthy process. In this study, we established a rapid and efficient optimized protocol for genetic transformation of E. breviscapus using the hybrid orthogonal method. The effect of different concentrations of selection pressure (Hygromycin B) on callus induction and the optimal pre-culture time of 7 days were demonstrated. The optimal transformation conditions were as follows: precipitant agents MgCl2 + PEG, target tissue distance 9 cm, helium pressure 650 psi, bombardment once, plasmid DNA concentration 1.0 μg·μL−1, and chamber vacuum pressure 27 mmHg. Integration of the desired genes was verified by amplifying 1.02 kb of htp gene from the T0 transgenic line. Genetic transformation of E. breviscapus was carried out by particle bombardment under the optimized conditions, and a stable transformation efficiency of 36.7% was achieved. This method will also contribute to improving the genetic transformation rate of other medicinal plants.

Neuroprotective Strategies for Stroke by Natural Products: Advances and Perspectives

Cerebral ischemic stroke is a disease with high prevalence and incidence. Its management focuses on rapid reperfusion with intravenous thrombolysis and endovascular thrombectomy. Both therapeutic strategies reduce disability, but the therapy time window is short, and the risk of bleeding is high. Natural products (NPs) have played a key role in drug discovery, especially for cancer and infectious diseases. However, they have made little progress in clinical translation and pose challenges to the treatment of stroke. Recently, with the investigation of precise mechanisms in cerebral ischemic stroke and the technological development of NP-based drug discovery, NPs are addressing these challenges and opening up new opportunities in cerebral stroke. Thus, in this review, we first summarize the structure and function of diverse NPs, including flavonoids, phenols, terpenes, lactones, quinones, alkaloids, and glycosides. Then we propose the comprehensive neuroprotective mechanism of NPs in cerebral ischemic stroke, which involves complex cascade processes of oxidative stress, mitochondrial damage, apoptosis or ferroptosis-related cell death, inflammatory response, and disruption of the blood-brain barrier (BBB). Overall, we stress the neuroprotective effect of NPs and their mechanism on cerebral ischemic stroke for a better understanding of the advances and perspective in NPs application that may provide a rationale for the development of innovative therapeutic regimens in ischemic stroke.

Cornin protects against cerebral ischemia/reperfusion injury by preventing autophagy via the PI3K/Akt/mTOR pathway

Background

Ischemia stroke is the leading cause of disability, which is a consequence of vascular occlusion. The purpose of this study is to investigate the effect of cornin which is isolated from the fruit of Verbena officinalis L, against astrocytes autophagy induced by cerebral ischemia/reperfusion (CI/R) injury in vitro and in vivo and its potential mechanism.

Methods

Cornin at dose of 2.5, 5 and 10 mg/kg were intravenously injected to MCAO rats at 15 min after reperfusion. The infarction volume, blood–brain barrier (BBB), neurological severity score (mNSS), and autophagy related protein were used to evaluated the protective effects and potential mechanism of cornin in autophagy with or without phosphoinositide-3 kinase (PI3K)inhibitor LY294002 and mammalian target of rapamycin (mTOR) small interfering RNA (siRNA) at 24 h after CI/R injury. The potential protective effects and mechanism of cornin at concention of 10 ~ 1000 nM were also evaluated in oxygen glucose deprivation/reperfusion (OGD/R) in U87 cells.

Results

The results suggest that cornin at dose of 5 or 10 mg/kg significantly reduce the cerebral infarction volume and blood–brain barrier (BBB) leakage, and improve neurological recovery in MCAO rats. Cleaved caspase-3 and Bax levels were significantly decreased, while B-cell lymphoma-2 (Bcl-2) and the apoptosis regulator ratio (Bcl-2/Bax) were markedly increased when treated with 2.5–10 mg/kg cornin. The obvious decreased expressions of glial fibrillary acidic protein (GFAP), myosin-like BCL2 interacting protein (Beclin-1) and microtubule-associated protein light chain 3 II (LC3-II) and increased of neuronal nuclei (NeuN), sequestosome-1 (p62), phosphorylated mTOR (p-mTOR), and phosphorylated Akt (p-Akt) were observed in MCAO rats treated with 10 mg/kg cornin, which was counteracted by LY294002. The expression of autophagy-related proteins with or without LY294002 and mTOR siRNA presented the similar results as in vitro in OGD/R in U87 cells.

Conclusions

These results indicate that cornin improved neurological recovery after cerebral ischemia injury by preventing astrocytes autophagy induced by CI/R via the PI3K/Akt/mTOR signaling pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40360-022-00620-3.

Development of an autophagy activator from Class III PI3K complexes, Tat-BECN1 peptide: Mechanisms and applications

Impairment or dysregulation of autophagy has been implicated in many human pathologies ranging from neurodegenerative diseases, infectious diseases, cardiovascular diseases, metabolic diseases, to malignancies. Efforts have been made to explore the therapeutic potential of pharmacological autophagy activators, as beneficial health effects from caloric restriction or physical exercise are linked to autophagy activation. However, the lack of specificity remains the major challenge to the development and clinical use of autophagy activators. One candidate of specific autophagy activators is Tat-BECN1 peptide, derived from Beclin 1 subunit of Class III PI3K complexes. Here, we summarize the molecular mechanisms by which Tat-BECN1 peptide activates autophagy, the strategies for optimization and development, and the applications of Tat-BECN1 peptide in cellular and organismal models of physiology and pathology.

Research progress on astrocyte autophagy in ischemic stroke

Ischemic stroke is a highly disabling and potentially fatal disease. After ischemic stroke, autophagy plays a key regulatory role as an intracellular catabolic pathway for misfolded proteins and damaged organelles. Mounting evidence indicates that astrocytes are strongly linked to the occurrence and development of cerebral ischemia. In recent years, great progress has been made in the investigation of astrocyte autophagy during ischemic stroke. This article summarizes the roles and potential mechanisms of astrocyte autophagy in ischemic stroke, briefly expounds on the crosstalk of astrocyte autophagy with pathological mechanisms and its potential protective effect on neurons, and reviews astrocytic autophagy-targeted therapeutic methods for cerebral ischemia. The broader aim of the report is to provide new perspectives and strategies for the treatment of cerebral ischemia and a reference for future research on cerebral ischemia.

The Emerging Role of Astrocytic Autophagy in Central Nervous System Disorders

Astrocytes act as "housekeeping cells" for maintaining cerebral homeostasis and play an important role in many disorders. Recent studies further highlight the contribution of autophagy to astrocytic functions, including astrogenesis, the astrocytic removal of neurotoxins or stressors, and astrocytic polarization. More importantly, genetic and pharmacological approaches have provided evidence that outlines the contributions of astrocytic autophagy to several brain disorders, including neurodegeneration, cerebral ischemia, and depression. In this study, we summarize the emerging role of autophagy in regulating astrocytic functions and discuss the contributions of astrocytic autophagy to different CNS disorders.

Breviscapine alleviates NASH by inhibiting TGF-β-activated kinase 1-dependent signaling

BACKGROUND AND AIMS

NAFLD is a key component of metabolic syndrome, ranging from nonalcoholic fatty liver to NASH, and is now becoming the leading cause of cirrhosis and HCC worldwide. However, due to the complex and unclear pathophysiological mechanism, there are no specific approved agents for treating NASH. Breviscapine, a natural flavonoid prescription drug isolated from the traditional Chinese herb Erigeron breviscapus, exhibits a wide range of pharmacological properties, including effects on metabolism. However, the anti-NASH efficacy and mechanisms of breviscapine have not yet been characterized.

APPROACH AND RESULTS

We evaluated the effects of breviscapine on the development of hepatic steatosis, inflammation, and fibrosis in vivo and in vitro under metabolic stress. Breviscapine treatment significantly reduced lipid accumulation, inflammatory cell infiltration, liver injury, and fibrosis in mice fed a high-fat diet, a high-fat/high-cholesterol diet, or a methionine- and choline-deficient diet. In addition, breviscapine attenuated lipid accumulation, inflammation, and lipotoxicity in hepatocytes undergoing metabolic stress. RNA-sequencing and multiomics analyses further indicated that the key mechanism linking the anti-NASH effects of breviscapine was inhibition of TGF-β-activated kinase 1 (TAK1) phosphorylation and the subsequent mitogen-activated protein kinase signaling cascade. Treatment with the TAK1 inhibitor 5Z-7-oxozeaenol abrogated breviscapine-mediated hepatoprotection under metabolic stress. Molecular docking illustrated that breviscapine directly bound to TAK1.

CONCLUSION

Breviscapine prevents metabolic stress-induced NASH progression through direct inhibition of TAK1 signaling. Breviscapine might be a therapeutic candidate for the treatment of NASH.

Polyphenols for the Treatment of Ischemic Stroke: New Applications and Insights

Ischemic stroke (IS) is a leading cause of death and disability worldwide. Currently, the main therapeutic strategy involves the use of intravenous thrombolysis to restore cerebral blood flow to prevent the transition of the penumbra to the infarct core. However, due to various limitations and complications, including the narrow time window in which this approach is effective, less than 10% of patients benefit from such therapy. Thus, there is an urgent need for alternative therapeutic strategies, with neuroprotection against the ischemic cascade response after IS being one of the most promising options. In the past few decades, polyphenolic compounds have shown great potential in animal models of IS because of their high biocompatibility and ability to target multiple ischemic cascade signaling pathways, although low bioavailability is an issue that limits the applications of several polyphenols. Here, we review the pathophysiological changes following cerebral ischemia and summarize the research progress regarding the applications of polyphenolic compounds in the treatment of IS over the past 5 years. Furthermore, we discuss several potential strategies for improving the bioavailability of polyphenolic compounds as well as some essential issues that remain to be addressed for the translation of the related therapies to the clinic.

Metabolic engineering of Yarrowia lipolytica for scutellarin production

Scutellarin related drugs have superior therapeutic effects on cerebrovascular and cardiovascular diseases. Here, an optimal biosynthetic pathway for scutellarin was constructed in Yarrowia lipolytica platform due to its excellent metabolic potential. By integrating multi-copies of core genes from different species, the production of scutellarin was increased from 15.11 mg/L to 94.79 mg/L and the ratio of scutellarin to the main by-product was improved about 110-fold in flask condition. Finally, the production of scutellarin was improved 23-fold and reached to 346 mg/L in fed-batch bioreactor, which was the highest reported titer for de novo production of scutellarin in microbes. Our results represent a solid basis for further production of natural products on unconventional yeasts and have a potential of industrial implementation.

Valproic Acid Inhibits Glial Scar Formation after Ischemic Stroke

INTRODUCTION

Cerebral ischemia induces reactive proliferation of astrocytes (astrogliosis) and glial scar formation. As a physical and biochemical barrier, the glial scar not only hinders spontaneous axonal regeneration and neuronal repair but also deteriorates the neuroinflammation in the recovery phase of ischemic stroke.

OBJECTIVES

Previous studies have shown the neuroprotective effects of the valproic acid (2-n-propylpentanoic acid, VPA) against ischemic stroke, but its effects on the ischemia-induced formation of astrogliosis and glial scar are still unknown. As targeting astrogliosis has become a therapeutic strategy for ischemic stroke, this study was designed to determine whether VPA can inhibit the ischemic stroke-induced glial scar formation and to explore its molecular mechanisms.

METHODS

Glial scar formation was induced by an ischemia-reperfusion (I/R) model in vivo and an oxygen and glucose deprivation (OGD)-reoxygenation (OGD/Re) model in vitro. Animals were treated with an intraperitoneal injection of VPA (250 mg/kg/day) for 28 days, and the ischemic stroke-related behaviors were assessed.

RESULTS

Four weeks of VPA treatment could markedly reduce the brain atrophy volume and improve the behavioral deficits in rats' I/R injury model. The results showed that VPA administrated upon reperfusion or 1 day post-reperfusion could also decrease the expression of the glial scar makers such as glial fibrillary acidic protein, neurocan, and phosphacan in the peri-infarct region after I/R. Consistent with the in vivo data, VPA treatment showed a protective effect against OGD/Re-induced astrocytic cell death in the in vitro model and also decreased the expression of GFAP, neurocan, and phosphacan. Further studies revealed that VPA significantly upregulated the expression of acetylated histone 3, acetylated histone 4, and heat-shock protein 70.1B in the OGD/Re-induced glial scar formation model.

CONCLUSION

VPA produces neuroprotective effects and inhibits the glial scar formation during the recovery period of ischemic stroke via inhibition of histone deacetylase and induction of Hsp70.1B.

Advances in Chemical Constituents, Clinical Applications, Pharmacology, Pharmacokinetics and Toxicology of Erigeron breviscapus

Dengzhanxixin (DZXX), the dried whole plant of Erigeron breviscapus (Vaniot) Hand.-Mazz., belonging to Compositae and first published in Materia Medica of South Yunnan by Lan Mao in the Ming Dynasty (1368 AD–1644 AD), is included in Medicinal Materials and Decoction Pieces of the 2020 edition of the Pharmacopeia of the People’s Republic of China. Its main chemical components are flavonoids that mainly include flavonoid, flavonols, dihydroflavones, flavonol glycosides, flavonoid glycosides, coffee acyl compounds, and other substances, such as volatile oil compounds, coumarins, aromatic acids, pentacyclic terpenoids, phytosterols, and xanthones. Among them, scutellarin and 1,5-dicoffeoylquininic acid are the main active components of DZXX. DZXX has pharmacological effects, such as improving cerebral and cerebrovascular ischemia, increasing blood flow, inhibiting platelet aggregation, promoting antithrombotic formation, improving microcirculation, reducing blood viscosity, protecting optic nerves, exhibiting anti-inflammatory properties, scavenging free radicals, and eliciting antioxidant activities. It is widely used in the treatment of cardiovascular and cerebrovascular ischemic diseases, kidney diseases, liver diseases, diabetic complications, and glaucoma. Pharmacokinetic studies have shown that the active components of DZXX have a low bioavailability and a high elimination rate in vivo. Nevertheless, its utilization can be improved through liposome preparation and combination with other drugs. Acute and subacute toxicity studies have shown that DZXX is a safe medicinal material widely used in clinical settings. However, its target and drug action mechanism are unclear because of the complexity of its composition. In this paper, the clinical application and pharmacological toxicology of DZXX are reviewed to provide a reference for further studying its active components and action mechanism.

Circular RNA 0025984 Ameliorates Ischemic Stroke Injury and Protects Astrocytes Through miR-143-3p/TET1/ORP150 Pathway

MiR-143-3p is aberrantly expressed in patients with ischemic stroke and associated with ischemic brain injury. However, the underlying mechanisms are largely unknown. Here, we confirmed circ_0025984 and TET1 as a sponge and target of miR-143-3p, respectively, by luciferase reporter assay. In astrocytes, OGD significantly decreased circ_0025984 and TET1 levels but increased miR-143-3p levels, which was also observed in brains of mice with MCAO. Treatment with miR-143-3p inhibitor or circ_0025984 significantly decreased astrocyte apoptosis and autophagy, as well as cerebral injury and neuron loss in mice with MCAO. Notably, TET1 overexpression decreased astrocyte apoptosis and autophagy and induced promoter hypomethylation and expression of ORP150. Our results demonstrated for the first time that circ_0025984 protects astrocytes from ischemia-induced autophagy and apoptosis by targeting the miR-143-3p/TET1 pathway and might inhibit cerebral injury induced by ischemic stroke. Furthermore, our data revealed the important positive regulation of ORP150 by TET1, which could be associated with its neuroprotective role. Graphical abstract Model for signaling pathway of circ_0025984/miR-143-3p/TET1 inastrocytes cultured under OGD. In astrocytes, circ_0025984 acts as a sponge of miR-143-3p, which directly targets TET1 and decreases its expression (A). After translocatinginto the nucleus, TET1 binds to the promoter of ORP150, converts 5mC into 5hmC,leading to DNA demethylation and increased expression of ORP150 (B). In astrocytescultured under OGD, ER stress is induced and eventually leads to apoptosis andautophagy mediated by ATG7, which is regulated by circ_0025984 via ORP150 andGRP78 (C).

25-Hydroxycholesterol protecting from cerebral ischemia-reperfusion injury through the inhibition of STING activity

Middle cerebral artery occlusion (MCAO) injury refers to impaired blood supply to the brain that is caused by a cerebrovascular disease, resulting in local brain tissue ischemia, hypoxic necrosis, and rapid neurological impairment. Nevertheless, the mechanisms involved are unclear, and pharmacological interventions are lacking. 25-Hydroxycholesterol (25-HC) was reported to be involved in cholesterol and lipid metabolism as an oxysterol molecule. This study aimed to determine whether 25-HC exerts a cerebral protective effect on MCAO injury and investigate its potential mechanism. 25-HC was administered prior to reperfusion in a mouse model of MCAO injury. 25-HC evidently decreased infarct size induced by MCAO and enhanced brain function. It reduced stimulator of interferon gene (STING) activity and regulated mTOR to inhibit autophagy and induce cerebral ischemia tolerance. Thus, 25-HC improved MCAO injury through the STING channel. As indicated in this preliminary study, 25-HC improved MCAO injury by inhibiting STING activity and autophagy as well as by reducing brain nerve cell apoptosis. Thus, it is a potential treatment drug for brain injury.

Role of Phytonutrients in Nutrigenetics and Nutrigenomics Perspective in Curing Breast Cancer

Breast cancer (BC) is one of the most common type of cancer and an important contributor to female mortality. Several genes and epigenetic modifications are involved in the development and progression of BC. Research in phytochemistry, nutrigenomics, and nutrigenetics has provided strong evidence that certain phytonutrients are able to modulate gene expression at transcriptional and post-transcriptional levels. Such phytonutrients may also be beneficial to prevent and treat BC. In this review, we will focus on the nutrigenomic effects of various phytochemicals including polyphenols, phytosterols, terpenoids, alkaloids, and other compounds from different sources. Overall, these phytonutrients are found to inhibit BC cell proliferation, differentiation, invasion, metastasis, angiogenesis, and induce apoptotic cell death by targeting various molecular pathways. They also alter epigenetic mechanisms and enhance the chemosensitivity and radiosensitivity of cancer cells. Such phytochemicals may be used for the effective management of BC patients in the clinical setting in the future. The present article aims to summarize the specific molecular pathways involved in the genetic effects of phytochemicals in BC.

Synthesis, Characterization, In Vitro Anticancer Potentiality, and Antimicrobial Activities of Novel Peptide-Glycyrrhetinic-Acid-Based Derivatives

Glycyrrhetinic acid (GA) is one of many interesting pentacyclic triterpenoids showing significant anticancer activity by triggering apoptosis in tumor cell lines. This study deals with the design and synthesis of new glycyrrhetinic acid (GA)-amino acid peptides and peptide ester derivatives. The structures of the new derivatives were established through various spectral and microanalytical data. The novel compounds were screened for their in vitro cytotoxic activity. The evaluation results showed that the new peptides produced promising cytotoxic activity against the human breast MCF-7 cancer cell line while comparing to doxorubicin. On the other hand, only compounds 3, 5, and 7 produced potent activity against human colon HCT-116 cancer cell line. The human liver cancer (HepG-2) cell line represented a higher sensitivity to peptide 7 (IC50; 3.30 μg/mL), while it appeared insensitive to the rest of the tested peptides. Furthermore, compounds 1, 3, and 5 exhibited a promising safety profile against human normal skin fibroblasts cell line BJ-1. In order to investigate the mode of action, compound 5 was selected as a representative example to study its in vitro effect against the apoptotic parameters and Bax/BCL-2/p53/caspase-7/caspase-3/tubulin, and DNA fragmentation to investigate beta (TUBb). Additionally, all the new analogues were subjected to antimicrobial assay against a panel of Gram-positive and Gram-negative bacteria and the yeast candida Albicans. All the tested GA analogues 1-8 exhibited more antibacterial effect against Micrococcus Luteus than gentamicin, but they exhibited moderate antimicrobial activity against the tested bacterial and yeast strains. Molecular docking studies were also simulated for compound 5 to give better rationalization and put insight to the features of its structure.

Multimodal Optical Imaging to Investigate Spatiotemporal Changes in Cerebrovascular Function in AUDA Treatment of Acute Ischemic Stroke

Administration of 12-(3-adamantan-1-yl-ureido)-dodecanoic acid (AUDA) has been demonstrated to alleviate infarction following ischemic stroke. Reportedly, the main effect of AUDA is exerting anti-inflammation and neovascularization via the inhibition of soluble epoxide hydrolase. However, the major contribution of this anti-inflammation and neovascularization effect in the acute phase of stroke is not completely elucidated. To investigate the neuroprotective effects of AUDA in acute ischemic stroke, we combined laser speckle contrast imaging and optical intrinsic signal imaging techniques with the implantation of a lab-designed cranial window. Forepaw stimulation was applied to assess the functional changes via measuring cerebral metabolic rate of oxygen (CMRO₂) that accompany neural activity. The rats that received AUDA in the acute phase of photothrombotic ischemia stroke showed a 30.5 ± 8.1% reduction in the ischemic core, 42.3 ± 15.1% reduction in the ischemic penumbra (p < 0.05), and 42.1 ± 4.6% increase of CMRO₂ in response to forepaw stimulation at post-stroke day 1 (p < 0.05) compared with the control group (N = 10 for each group). Moreover, at post-stroke day 3, increased functional vascular density was observed in AUDA-treated rats (35.9 ± 1.9% higher than that in the control group, p < 0.05). At post-stroke day 7, a 105.4% ± 16.4% increase of astrocytes (p < 0.01), 30.0 ± 10.9% increase of neurons (p < 0.01), and 65.5 ± 15.0% decrease of microglia (p < 0.01) were observed in the penumbra region in AUDA-treated rats (N = 5 for each group). These results suggested that AUDA affects the anti-inflammation at the beginning of ischemic injury and restores neuronal metabolic rate of O₂ and tissue viability. The neovascularization triggered by AUDA restored CBF and may contribute to ischemic infarction reduction at post-stroke day 3. Moreover, for long-term neuroprotection, astrocytes in the penumbra region may play an important role in protecting neurons from apoptotic injury.

Enriched environment boosts the post-stroke recovery of neurological function by promoting autophagy

Autophagy is crucial for maintaining cellular homeostasis, and can be activated after ischemic stroke. It also participates in nerve injury and repair. The purpose of this study was to investigate whether an enriched environment has neuroprotective effects through affecting autophagy. A Sprague-Dawley rat model of transient ischemic stroke was prepared by occlusion of the middle cerebral artery followed by reperfusion. One week after surgery, these rats were raised in either a standard environment or an enriched environment for 4 successive weeks. The enriched environment increased Beclin-1 expression and the LC3-II/LC3-I ratio in the autophagy/lysosomal pathway in the penumbra of middle cerebral artery-occluded rats. Enriched environment-induced elevations in autophagic activity were mainly observed in neurons. Enriched environment treatment also promoted the fusion of autophagosomes with lysosomes, enhanced the lysosomal activities of lysosomal-associated membrane protein 1, cathepsin B, and cathepsin D, and reduced the expression of ubiquitin and p62. After 4 weeks of enriched environment treatment, neurological deficits and neuronal death caused by middle cerebral artery occlusion/reperfusion were significantly alleviated, and infarct volume was significantly reduced. These findings suggest that neuronal autophagy is likely the neuroprotective mechanism by which an enriched environment promotes recovery from ischemic stroke. This study was approved by the Animal Ethics Committee of the Kunming University of Science and Technology, China (approval No. 5301002013855) on March 1, 2019.

Pentacyclic Triterpenoids with Nitrogen-Containing Heterocyclic Moiety, Privileged Hybrids in Anticancer Drug Discovery

Pentacyclic triterpenoids are well-known phytochemicals with various biological activities commonly found in plants as secondary metabolites. The wide range of biological activities exhibited by triterpenoids has made them the most valuable sources of pharmacological agents. A number of novel triterpenoid derivatives with many skeletal modifications have been developed. The most important modifications are the formation of analogues or derivatives with nitrogen-containing heterocyclic scaffolds. The derivatives with nitrogen-containing heterocyclic compounds are among the most promising candidate for the development of novel therapeutic drugs. About 75% of FDA-approved drugs are nitrogen-containing heterocyclic moieties. The unique properties of heterocyclic compounds have encouraged many researchers to develop new triterpenoid analogous with pharmacological activities. In this review, we discuss recent advances of nitrogen-containing heterocyclic triterpenoids as potential therapeutic agents. This comprehensive review will assist medicinal chemists to understand new strategies that can result in the development of compounds with potential therapeutic efficacy.

Improving Breviscapine Oral Bioavailability by Preparing Nanosuspensions, Liposomes and Phospholipid Complexes

Breviscapine (BVP), a flavonoid compound, is widely used in the treatment of cardiovascular and cerebrovascular diseases; however, the low oral bioavailability and short half-life properties limit its application. The aim of this study was to investigate the three preparations for improving its oral bioavailability: nanosuspensions (BVP-NS), liposomes (BVP-LP) and phospholipid complexes (BVP-PLC). In vitro and in vivo results suggested that these three could all significantly improved the cumulative released amount and oral bioavailability compared with physical mixture, in which BVP-PLC was the most optimal preparation with the relative bioavailability and mean retention time of 10.79 ± 0.25 (p < 0.01) and 471.32% (p < 0.01), respectively. Furthermore, the influence of drug-lipid ratios on the in vitro release and pharmacokinetic behavior of BVP-PLC was also studied and the results showed that 1:2 drug-lipid ratio was the most satisfactory one attributed to the moderate-intensity interaction between drug and phospholipid which could balance the drug loading and drug release very well.

Flavonoid compound breviscapine suppresses human osteosarcoma Saos-2 progression property and induces apoptosis by regulating mitochondria-dependent pathway

This study was aimed to investigate the ability of a flavonoid compound breviscapine (BVP) to suppress growth and elicit apoptosis in human osteosarcoma (OS) Saos-2 cells. The cells were cultured in vitro and treated with three concentrations of BVP (80, 160, and 320 μg/ml). Moreover, C57 mice were injected with Saos-2 cells to establish a subcutaneous xenograft model, and they were subsequently treated with three doses of BVP via intraperitoneal injection. The viability of the cells was examined by the Cell Counting Kit-8 method. The apoptotic cells were assessed by flow cytometry and terminal deoxynucleotidyl transferase dUTP nick end labeling staining. The tumor volume and weight were monitored from day 3 through day 21 after the last injection. The expression of bax, bcl-2, and cytochrome c (cyt c) mRNA was detected by a real-time polymerase chain reaction. The protein levels of bax, bcl-2, cyt c, caspase 3, and caspase 9 were evaluated by Western blot. The expression and distribution of bcl-2 and bax in tissues were detected by immunohistochemistry. Compared with the control group, BVP treatment inhibited cell proliferation and induced apoptosis of Saos-2 cells in vitro. Consistently, treatment of mice bearing transplanted tumors with BVP suppressed the growth of OS tumors and promoted cell apoptosis; it also reduced tumor volume and weight. Mechanistically, BVP-induced apoptosis was mediated by the mitochondria-dependent pathway, as evidenced by the increased expression of bax and cyt c and the decreased expression of bcl-2, as well as activation of caspase 9 and caspase 3 in vitro and in vitro. Collectively, BVP inhibits growth and promotes apoptosis of OS by activating the mitochondrial apoptosis pathway.

Breviscapine Alleviates Cognitive Impairments Induced by Transient Cerebral Ischemia/Reperfusion through Its Anti-Inflammatory and Anti-Oxidant Properties in a Rat Model

Cerebral ischemia/reperfusion (I/R)-induced injury is a common phenomenon of stroke, and the effective treatment for I/R-induced brain tissue damage is limited. Breviscapine has been widely used in China as herbal medicine to treat cardiovascular diseases for hundreds of years and has been demonstrated to possess potent cardiovascular pharmacological effects. This study aims to investigate the neuroprotective effect of breviscapine on cerebral I/R-induced injury. The rat model of middle cerebral artery occlusion (MCAO) was applied in our study. The cerebral I/R rats received multiple injections of breviscapine. All rats were subject to neurological behavior tests by open field test and Morris water maze test. The pro-inflammatory cytokines and oxidative stress marker levels were determined by ELISA and colorimetric analysis, respectively. We demonstrated that administration of breviscapine dose-dependently ameliorated cerebral I/R-induced injury and improved the neurological performance of cerebral I/R rats. Further studies illustrated that breviscapine treatment effectively attenuated inflammatory cytokine expression, reduced oxidative stress, and pro-apoptosis protein expression and inhibited the activation of NF-κB signaling and microglia in the I/R injury tissues. Breviscapine may serve as a single drug or a promising adjuvant that can be used in conjunction with other medicine for the treatment of cerebral I/R-induced injury.

Calcium Dynamics in Astrocytes During Cell Injury

The changes in intracellular calcium concentration ([Ca²⁺]) following laser-induced cell injury in nearby cells were studied in primary mouse astrocytes selectively expressing the Ca²⁺ sensitive GFAP-Cre Salsa6f fluorescent tandem protein, in an Ast1 astrocyte cell line, and in primary mouse astrocytes loaded with Fluo4. Astrocytes in these three systems exhibit distinct changes in [Ca²⁺] following induced death of nearby cells. Changes in [Ca²⁺] appear to result from release of Ca²⁺ from intracellular organelles, as opposed to influx from the external medium. Salsa6f expressing astrocytes displayed dynamic Ca²⁺ changes throughout the phagocytic response, including lamellae protrusion, cytosolic signaling during vesicle formation, vesicle maturation, and vesicle tract formation. Our results demonstrate local changes in [Ca²⁺] are involved in the process of phagocytosis in astrocytes responding to cell corpses and/or debris.

Chemical Modulation of Mitochondria-Endoplasmic Reticulum Contact Sites

Contact sites between mitochondria and endoplasmic reticulum (ER) are points in which the two organelles are in close proximity. Due to their structural and functional complexity, their exploitation as pharmacological targets has never been considered so far. Notwithstanding, the number of compounds described to target proteins residing at these interfaces either directly or indirectly is rising. Here we provide original insight into mitochondria–ER contact sites (MERCs), with a comprehensive overview of the current MERCs pharmacology. Importantly, we discuss the considerable potential of MERCs to become a druggable target for the development of novel therapeutic strategies.

A Preliminary Study on the Effect and Mechanism of Breviscapine for Improving Insulin Resistance in HepG2 Cells

Insulin resistance (IR) is known to be a critical factor, which can lead to the onset of type 2 diabetes. Traditional Chinese medicine (TCM) has special advantages in treating IR, but the active components and action mechanisms of most TCM remain unclear. Therefore, the elucidation of the potential mechanisms is a major challenge in TCM research. In the study, we tried to elucidate the potential pharmacological efficacy and mechanism of breviacapine for improving IR through network analysis and validate the possible biological target for its quality evaluation. We computationally recognized the active components, potential targets, and the targets closely related to IR by using integrative analysis based on network pharmacology approach. We also established the active components-targets network, protein interactions network and analyzing the biological functions and pathways of targets to evaluate the links between components and pharmacological actions to help explain the action mechanisms of breviscapine. Based on the network analysis, our experimental data preliminarily confirmed that breviscapine could improve IR in HepG2 cells, which may be associated with the dynamic regulation of the PTP1B. This study combined network pharmacology with partial experiment validation to clarify the underlying mechanism of breviscapine in improving IR and thus laid the experimental foundation for the depth exploration of its functional mechanism.

Breviscapine suppresses the growth and metastasis of prostate cancer through regulating PAQR4-mediated PI3K/Akt pathway

OBJECTIVES

Prostate cancer, one of the most frequently diagnosed tumors of men, leads to poor quality of life. Previous studies have shown that breviscapine (BRE) exerts therapeutic activity in malignant tumors. However, the role and mechanism of BRE exhibit an anti-tumor effect on prostate cancer are largely unknown.

METHODS

The mRNA and protein levels in prostate cancer tissues and cell lines were measured using RT-qPCR, western blot, and immunohistochemical staining, respectively. Cell proliferation, invasion, and migration in both PC3 and DU145 cells were evaluated using CCK-8 and Transwell assay. The effect of BRE on cell proliferation and metastasis by regulating the PAQR4-mediated PI3K/Akt pathway in vitro and in vivo was determined.

RESULTS

PAQR4 was significantly overexpressed in prostate cancer tissues and cell lines, which was positively correlated with poor prognosis. Knockdown of PAQR4 inhibited the proliferation, invasion, migration, and epithelial-mesenchymal transition (EMT) of both PC3 and DU145 cells. Mechanistically, BRE treatment significantly suppressed the malignant biological behavior of both prostate cancer cells by downregulating PAQR4 and blocking the PI3K/Akt pathway. In vivo experiments, BRE administration remarkably inhibited tumor growth and metastasis in a xenograft model of prostate cancer.

CONCLUSION

Our findings revealed that BRE exerts anti-tumor and anti-metastasis roles in prostate cancer by inhibiting PAQR4-mediated PI3K/Akt pathway, which provides a new therapeutic agent for prostate cancer clinical treatment.

Nose to brain drug delivery - A promising strategy for active components from herbal medicine for treating cerebral ischemia reperfusion

Cerebral ischemia reperfusion injury (CIRI), one of the major causes of death from stroke in the world, not only causes tremendous damage to human health, but also brings heavy economic burden to society. Current available treatments for CIRI, including mechanical therapies and drug therapies, are often accompanied by significant side-effects. Therefore, it is necessary to discovery new strategies for treating CIRI. Many studies have confirmed that the herbal medicine has the advantages of abundant resources, good curative effect and little side effects, which can be used as potential drug for treatment of CIRI through multiple targets. It's known that oral administration commonly has low bioavailability, and injection administration is inconvenient and unsafe. Many drugs can't delivery to brain through routine pathways due to the blood-brain-barrier (BBB). Interestingly, increasing evidences have suggested the nasal administration is a potential direct route to transport drug into brain avoiding the BBB and has the characteristics of high bioavailability for treating brain diseases. Therefore, intranasal administration can be treated as an alternative way to treat brain diseases. In the present review, effective methods to treat CIRI by using active ingredients derived from herbal medicine through nose to brain drug delivery (NBDD) are updated and discussed, and some related pharmacological mechanisms have also been emphasized. Our present study would be beneficial for the further drug development of natural agents from herbal medicines via NBDD.

Electroacupuncture pretreatment prevents ischemic stroke and inhibits Wnt signaling-mediated autophagy through the regulation of GSK-3β phosphorylation

Electroacupuncture (EA), a traditional Chinese replacement therapy, is widely accepted to treat ischemic stroke. Increasing evidence show that autophagy is involved in the process of cerebral ischemia injury and the Wnt/GSK3β pathway, playing an important role in protecting central nervous system. In this study, rats were treated with EA prior to focal ischemia by middle cerebral artery occlusion (MCAO). Deficit score, infarct volumes and levels of autophagy markers, such as LC3I, LC3II and p62, were assessed with either PI3K inhibitor wortmannin or a GSK-3β inhibitor LiCl. Oxygen-glucose deprivation/re-oxygenation (OGD/R) was made in the primitive neuron in vitro, and was respectively treated with autophagy inhibitors 3-MA, LiCl, GSK3β siRNA, or mTOR inhibitor rapamycin. The results indicated that EA pretreatment increased the levels of autophagy marker LC3-II and reduced the levels of p62. Meanwhile, deficit outcome was improved, and infarct volumes were reduced by EA pretreatment. Furthermore, the beneficial effects of EA pretreatment were reversed by wortmannin. LiCl and GSK3β siRNA can mimic the neuroprotective effects of EA pretreatment by downregulating autophagy, and increasing protein levels of p-mTOR, p-GSK3β and β-catenin in OGD/R neurons. However, the protective effects of GSK3β siRNA were blocked by rapamycin. These results suggest that EA pretreatment induces tolerance to cerebral ischemia by inhibiting autophagy via the Wnt pathway through the inhibition of GSK3β.

Electroacupuncture Alleviates Cerebral Ischemia/Reperfusion Injury in Rats by Histone H4 Lysine 16 Acetylation-Mediated Autophagy

Background: Electroacupuncture (EA) treatment in ischemic stroke has been highlighted recently; however, the specific mechanism is still elusive. Autophagy is considered a new target for cerebral ischemia/reperfusion (I/R), but whether it plays a role of protecting or causing rapid cell apoptosis remains unclear. Studies have reported that the reduction in lysine 16 of histone H4 acetylation coheres with autophagy induction. The primary purpose of the study was to explore whether EA could alleviate I/R via autophagy-mediated histone H4 lysine 16 acetylation in the middle cerebral artery occlusion (MCAO) rat model. Methods: One hundred and twenty male Sprague-Dawley rats were divided into five groups: control group, MCAO group, MCAO+EA group, MCAO+EA+hMOF siRNA group, and MCAO+EA+Sirt1 inhibitor group. EA was applied to "Baihui" (Du20) and "Renzhong" (Du26) at 5 min after modeling and 16 h after the first EA intervention. The structure and molecular markers of the rat brain were evaluated. Results: EA significantly alleviated I/R injury by upregulating the expressions of Sirt1, Beclin1, and LC3-II and downregulating the expressions of hMOF and H4K16ac. In contrast, the Sirt1 inhibitor lowered the increase in Sirt1, Beclin1, and LC3-II and enhanced the level of hMOF and H4K16ac expressions associated with EA treatment. Besides, ChIP assay revealed that the binding of H4K16ac in the Beclin1 promoter region of the autophagy target gene was significantly raised in the MCAO+EA group and MCAO+EA+hMOF siRNA group. Conclusions: EA treatment inhibited the H4K16ac process, facilitated autophagy, and alleviated I/R injury. These findings suggested that regulating histone H4 lysine 16 acetylation-mediated autophagy may be a key mechanism of EA at Du20 and Du26 to treat I/R.

Schizandrin Protects against OGD/R-Induced Neuronal Injury by Suppressing Autophagy: Involvement of the AMPK/mTOR Pathway

The neuroprotective role of schizandrin (SA) in cerebral ischemia-reperfusion (I/R) was recently highlighted. However, whether SA plays a regulatory role on autophagy in cerebral I/R injury is still unclear. This study aimed to explore whether the neuroprotective mechanisms of SA were linked to its regulation of AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR)/autophagy pathway in vivo and in vitro. The present study confirmed that SA significantly improved oxygen-glucose deprivation/re-oxygenation (OGD/R)-induced PC12 cells injury. The results of immunoblotting and confocal microscope showed that SA decreased autophagy in OGD/R-injured PC12 cells, which was reflected by the decreased Beclin-1 and LC3-II expression, autophagy flux level, and LC3 puncta formation. In addition, the autophagy inducer rapamycin partially prevented the effects of SA on cell viability and autophagy after OGD/R, whereas the autophagy inhibitor 3-methyladenine (3-MA) exerted the opposite effect. The results of Western blotting showed that SA markedly decreased the phosphorylation of AMPK (p-AMPK), whereas the phosphor-mTOR (p-mTOR) levels increased in the presence of OGD/R insult. Furthermore, pretreatment with the AMPK inducer AICAR partially reversed the protective effects and autophagy inhibition of SA. However, AMPK inhibitor Compound C pretreatment further promoted the inhibition of SA on autophagy induction and cell damage induced by OGD/R. Taken together, these findings demonstrate that SA protects against OGD/R insult by inhibiting autophagy through the regulation of the AMPK-mTOR pathway and that SA may have therapeutic value for protecting neurons from cerebral ischemia.

IL-1β receptor antagonist (IL-1Ra) combined with autophagy inducer (TAT-Beclin1) is an effective alternative for attenuating extracellular matrix degradation in rat and human osteoarthritis chondrocytes

Background

Autophagy induction is an effective approach for OA therapy. IL-1β is one of the major inflammatory cytokines linked to OA pathological progression, and its receptor blockade interrupts OA cartilage destruction. The objective of this study was to decipher the link between autophagy and regulatory mechanism of IL-1β and to investigate the effect of IL-1β receptor blockade by IL-1 receptor antagonist (IL-1Ra) combined with or without an autophagy inducer (TAT-Beclin1) on extracellular matrix (ECM) in OA chondrocytes in vitro and in vivo.

Methods

IL-1β-treated rat and human OA chondrocytes were cultured in response to IL-1Ra. The expression and distribution of signal molecules regulating ECM synthesis and autophagy were investigated via western blotting, immunoprecipitation, real-time PCR, immunofluorescence, and transmission electron microscope technique. Furthermore, after intra-articular injection of IL-1Ra, TAT-Beclin1, and a combination of both in a rat OA model established by anterior cruciate ligament transection and medial meniscus resection, the morphological changes of cartilage and related signal molecule expression levels were monitored using H.E., Safranin O-Fast green, and immunohistochemistry staining.

Results

Reduced autophagy by IL-1β contributed to ECM degradation, and blockade of IL-1β by IL-1Ra restored autophagy and attenuated ECM degradation in rat and human OA chondrocytes, as well as in a rat OA model. Akt/mTOR/ULK1, Akt/mTOR/NF-κB, and LC3B deacetylation were involved in autophagy regulated by IL-1β. Intra-articular injection of IL-1Ra combined with TAT-Beclin1 was more effective than IL-1Ra alone.

Conclusions

IL-1Ra restored autophagy and attenuated ECM degradation, with an implication that blocking IL-1β combined with enhancing autophagy might be a potential therapeutic strategy for OA.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1952-5) contains supplementary material, which is available to authorized users.

Proteostasis During Cerebral Ischemia

Cerebral ischemia is a complex pathology involving a cascade of cellular mechanisms, which deregulate proteostasis and lead to neuronal death. Proteostasis refers to the equilibrium between protein synthesis, folding, transport, and protein degradation. Within the brain proteostasis plays key roles in learning and memory by controlling protein synthesis and degradation. Two important pathways are implicated in the regulation of proteostasis: the unfolded protein response (UPR) and macroautophagy (called hereafter autophagy). Both are necessary for cell survival, however, their over-activation in duration or intensity can lead to cell death. Moreover, UPR and autophagy can activate and potentiate each other to worsen the issue of cerebral ischemia. A better understanding of autophagy and ER stress will allow the development of therapeutic strategies for stroke, both at the acute phase and during recovery. This review summarizes the latest therapeutic advances implicating ER stress or autophagy in cerebral ischemia. We argue that the processes governing proteostasis should be considered together in stroke, rather than focusing either on ER stress or autophagy in isolation.

Neuropharmacokinetics: a bridging tool between CNS drug development and therapeutic outcome

WHO classified neurological disorders to be among 6.3% of the global disease burden. Among the most central aspects of CNS drug development is the ability of novel molecules to cross the blood-brain barrier (BBB) to reach the target site over a desired time period for therapeutic action. Based on various aspects, brain pharmacokinetics is considered to be one of the foremost perspectives for the higher attrition rate of CNS biologics. Although drug traits are important, the BBB and blood-cerebrospinal fluid barrier together with transporters become the mechanistic approach behind CNS drug delivery. The present review emphasizes neuropharmacokinetic parameters, their importance, an assessment approach and the vast effect of transporters to brain drug distribution for CNS drug discovery.

1, 25-D3 Protects From Cerebral Ischemia by Maintaining BBB Permeability via PPAR-γ Activation

The blood-brain barrier (BBB) is a physical and biochemical barrier that maintains cerebral homeostasis. BBB dysfunction in an ischemic stroke, results in brain injury and subsequent neurological impairment. The aim of this study was to determine the possible protective effects of 1, 25-dihydroxyvitamin D3 [1, 25(OH)2D3, 1, 25-D3, vit D] on BBB dysfunction, at the early stages of an acute ischemic brain injury. We analyzed the effects of 1, 25-D3 on BBB integrity in terms of histopathological changes, the neurological deficit, infarct size and the expression of brain derived neurotrophic factor (BDNF), in a middle cerebral artery occlusion/reperfusion (MCAO/R) rat model. BBB permeability and the expression of permeability-related proteins in the brain were also evaluated by Evans blue (EB) staining and Western blotting respectively. To determine the possible mechanism underlying the role of 1, 25-D3 in BBB maintenance, after MCAO/R, the rats were treated with the specific peroxisome proliferator-activated receptor gamma (PPARγ) inhibitor GW9662. Supplementation with 1, 25-D3 markedly improved the neurological scores of the rats, decreased the infarct volume, prevented neuronal deformation and upregulated the expression of the tight junction (TJ) and BDNF proteins in their brains. Furthermore, it activated PPARγ but downregulated neuro-inflammatory cytokines such as nuclear factor kappa-B (NF-κB) and tumor necrosis factor-α (TNF-α), after MCAO/R. Taken together, 1, 25-D3 protects against cerebral ischemia by maintaining BBB permeability, upregulating the level of BDNF and inhibiting PPARγ-mediated neuro-inflammation.