Pharmacokinetic and metabolomic analyses of the neuroprotective effects of salvianolic acid A in a rat ischemic stroke model

Salvianolic acid A inhibits ferroptosis and protects against intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is a common cerebral vascular disease with high incidence, disability, and mortality. Ferroptosis is a regulated type of iron-dependent, non-apoptotic programmed cell death. There is increasing evidence that ferroptosis may lead to neuronal damage mediated by hemorrhagic stroke mediated neuronal damage. Salvianolic acid A (SAA) is a natural bioactive polyphenol compound extracted from salvia miltiorrhiza, which has anti-inflammatory, antioxidant, and antifibrosis activities. SAA is reported to be an iron chelator that inhibits lipid peroxidation and provides neuroprotective effects. However, whether SAA improves neuronal ferroptosis mediated by hemorrhagic stroke remains unclear. The study aims to evaluate the therapeutic effect of SAA on Ferroptosis mediated by Intracerebral hemorrhage and explore its potential mechanisms. We constructed in vivo and in vitro models of intracerebral hemorrhage in rats. Multiple methods were used to analyze the inhibitory effect of SAA on ferroptosis in both in vivo and in vitro models of intracerebral hemorrhage in rats. Then, network pharmacology is used to identify potential targets and mechanisms for SAA treatment of ICH. The SAA target ICH network combines SAA and ICH targets with protein-protein interactions (PPIs). Find the specific mechanism of SAA acting on ferroptosis through molecular docking and functional enrichment analysis. In rats, SAA (10 mg/kg in vivo and 50 μM in vitro, p < 0.05) alleviated dyskinesia and brain injury in the ICH model by inhibiting ferroptosis (p < 0.05). The molecular docking results and functional enrichment analyses suggested that AKT (V-akt murine thymoma viral oncogene homolog) could mediate the effect of SAA. NRF2 (Nuclear factor erythroid 2-related factor 2) was a potential target of SAA. Our further experiments showed that salvianolic acid A enhanced the Akt /GSK-3β/Nrf2 signaling pathway activation in vivo and in vitro. At the same time, SAA significantly expanded the expression of GPX4, XCT proteins, and the nuclear expression of Nrf2, while the AKT inhibitor SH-6 and the Nrf2 inhibitor ML385 could reduce them to some extent. Therefore, SAA effectively ameliorated ICH-mediated neuronal ferroptosis. Meanwhile, one of the critical mechanisms of SAA inhibiting ferroptosis was activating the Akt/GSK-3β/Nrf2 signaling pathway.

Jiawei Kongsheng Zhenzhong Pill: marker compounds, absorption into the serum (rat), and Q-markers identified by UPLC-Q-TOF-MS/MS

Background: The Jiawei Kongsheng Zhenzhong pill (JKZP), a Chinese herbal prescription comprised of eight Chinese crude drugs, has been historically employed to treat neurological and psychological disorders. Nevertheless, the ambiguous material basis severely hindered its progress and application. Purpose: The current study aimed to establish a rapid analytical method for identifying the chemical components of the JKZP aqueous extract and the components absorbed into the rat serum to investigate the quality markers (Q-markers) responsible for the neuroprotective effects of JKZP. Methods: The qualitative detection of the chemical components, prototype components, and metabolites of the aqueous extracts of JKZP, as well as the serum samples of rats that were administered the drug, was performed using the ultra-performance liquid chromatography- quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) technology. This analysis combined information from literature reports and database comparisons. Moreover, the study was conducted to anticipate the potential Q-markers for the neuroprotective effects of JKZP based on the "five principles" of Q-marker determination. Results: A total of 67 compounds and 111 serum components (comprising 33 prototypes and 78 metabolites) were detected and identified. Combining the principles of quality transmission and traceability, compound compatibility environment, component specificity, effectiveness, and measurability, the study predicted that five key compounds, namely, senkyunolide H, danshensu, echinacoside, loganin, and 3,6'-disinapoyl sucrose, may serve as potential pharmacological bases for the neuroprotective effects of JKZP. Conclusion: To summarize, the UPLC-Q-TOF-MS/MS technique can be employed to rapidly and accurately identify compounds in JKZP. Five active compounds have been predicted to be the Q-markers for the neuroprotective effects of JKZP. This discovery serves as a reference for improving quality, advancing further research and development, and utilizing Chinese herbal prescriptions.

Salvianolic acid A provides neuroprotective effects on cerebral ischemia-reperfusion injury in rats via PKA/CREB/c-Fos signaling pathway

BACKGROUND

Cerebral ischemia-reperfusion injury (CIRI) is a phenomenon that pathological injury of ischemic brain tissue is further aggravated after the restoration of blood supply. The complex pathological mechanism of CIRI has led to the failure of multiple neuroprotective agents in clinical studies. Salvianolic acid A (SAA) is a neuroprotective extract from Salvia miltiorrhiza Bge., with significant pharmacological activities in the treatment of brain injury. However, the neuroprotective mechanisms of SAA remain unclear.

PURPOSE

To explore the potential protective effect of SAA on CIRI and its mechanism, and to provide experimental basis for the research of new drugs for CIRI.

STUDY DESIGN

A model of transient middle cerebral artery occlusion (tMCAO) in rats was used to simulate clinical CIRI, and the neuroprotective effect of SAA on tMCAO rats was investigated within 14 days after reperfusion. The improvement effects of SAA on cognitive impairment of tMCAO rats were investigated by behavioral tests from days 7-14. Finally, the neuroprotective mechanism of SAA was investigated on day 14.

METHODS

The neuroprotective effects and mechanism of SAA were investigated by behavioral tests, HE and TUNEL staining, RNA sequence (RNA-seq) analysis and Western blot in tMCAO rats.

RESULTS

The brain protective effects of SAA were achieved by alleviating cerebral infarction, cerebral edema, cerebral atrophy and nerve injury in tMCAO rats. Meanwhile, SAA could effectively improve the cognitive impairment and pathological damage of hippocampal tissue, and inhibit cell apoptosis in tMCAO rats. Besides, SAA could provide neuroprotective effects by up-regulating the expression of Bcl-2, inhibiting the activation of Caspase 3, and regulating PKA/CREB/c-Fos signaling pathway.

CONCLUSION

SAA can significantly improve brain injury and cognitive impairment in CIRI rats, and this neuroprotective effect may be achieved through the anti-apoptotic effect and the regulation of PKA/CREB/c-Fos signaling pathway.

Increased fatty acid metabolism and decreased glycolysis are hallmarks of metabolic reprogramming within microglia in degenerating white matter during recovery from experimental stroke

The goal of this study was to evaluate changes in metabolic homeostasis during the first 12 weeks of recovery in a distal middle cerebral artery occlusion mouse model of stroke. To achieve this goal, we compared the brain metabolomes of ipsilateral and contralateral hemispheres from aged male mice up to 12 weeks after stroke to that of age-matched naïve and sham mice. There were 707 biochemicals detected in each sample by liquid chromatography-mass spectroscopy (LC-MS). Mitochondrial fatty acid β-oxidation, indicated by acyl carnitine levels, was increased in stroked tissue at 1 day and 4 weeks following stroke. Glucose and several glycolytic intermediates were elevated in the ipsilateral hemisphere for 12 weeks compared to the aged naïve controls, but pyruvate was decreased. Additionally, itaconate, a glycolysis inhibitor associated with activation of anti-inflammatory mechanisms in myeloid cells, was higher in the same comparisons. Spatial transcriptomics and RNA in situ hybridization localized these alterations to microglia within the area of axonal degeneration. These results indicate that chronic metabolic differences exist between stroked and control brains, including alterations in fatty acid metabolism and glycolysis within microglia in areas of degenerating white matter for at least 12 weeks after stroke.

Integrated pharmacokinetics and pharmacometabolomics to reveal the synergistic mechanism of a multicomponent Chinese patent medicine, Mailuo Shutong pills against thromboangiitis obliterans

BACKGROUND

Mailuo Shutong Pills (MLST) have displayed pharmacological activity against thromboangiitis obliterans (TAO). However, the active ingredients and therapeutic mechanism of MLST against TAO remained to be further clarified.

PURPOSE

The aim of this study was to explore the active components of MLST and their synergistic mechanism against TAO by integrating pharmacokinetics (PK) and pharmacometabolomics (PM).

METHODS

TAO model rats were established by sodium laurate solution. Firstly, the efficacy of MLST was evaluated by gangrene score, blood flow velocity, and hematoxylin-eosin (H&E) staining. Secondly, PK research was conducted on bioavailable components to characterize their dynamic behaviors under TAO. Thirdly, multiple plasma and urine metabolic biomarkers for sodium laurate-induced TAO rats were found by untargeted metabolomics, and then variations in TAO-altered metabolites following MLST treatment were analyzed utilizing multivariate and bioinformatic analysis. Additionally, metabolic pathway analysis was performed using MetaboAnalyst. Finally, the dynamic link between absorbed MLST-compounds and TAO-associated endogenous metabolites was established by correlation analysis.

RESULTS

MLST significantly alleviated gangrene symptoms by improving the infiltration of inflammatory cells and blood supply in TAO rats. Significant differences in metabolic profiles were found in 17 differential metabolites in plasma and 24 in urine between Sham and TAO rats. The 10 bioavailable MLST-compounds, such as chlorogenic acid and paeoniflorin, showed positive or negative correlations with various TAO-altered metabolites related to glutamate metabolism, histidine metabolism, arachidonic acid metabolism and so on.

CONCLUSION

This study originally investigated the dynamic interaction between MLST and the biosystem, providing unique insight for disclosing the active components of MLST and their synergistic mechanisms against TAO, which also shed light on new therapeutic targets for TAO and treatment.

Potential implications of polyphenolic compounds in neurodegenerative diseases

Neurodegenerative diseases are common chronic diseases related to progressive damage to the nervous system. Current neurodegenerative diseases present difficulties and despite extensive research efforts to develop new disease-modifying therapies, there is still no effective treatment for halting the neurodegenerative process. Polyphenols are biologically active organic compounds abundantly found in various plants. It has been reported that plant-derived dietary polyphenols may improve some disease states and promote health. Emerging pieces of evidence indicate that polyphenols are associated with neurodegenerative diseases. This review aims to overview the potential neuroprotective roles of polyphenols in most common neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease, epilepsy, and ischemic stroke.

Long-term administration of salvianolic acid A promotes endogenous neurogenesis in ischemic stroke rats through activating Wnt3a/GSK3β/β-catenin signaling pathway

Stroke is the major cause of death and disability worldwide. Most stroke patients who survive in the acute phase of ischemia display various extents of neurological deficits. In order to improve the prognosis of ischemic stroke, promoting endogenous neurogenesis has attracted great attention. Salvianolic acid A (SAA) has shown neuroprotective effects against ischemic diseases. In the present study, we investigated the neurogenesis effects of SAA in ischemic stroke rats, and explored the underlying mechanisms. An autologous thrombus stroke model was established by electrocoagulation. The rats were administered SAA (10 mg/kg, ig) or a positive drug edaravone (5 mg/kg, iv) once a day for 14 days. We showed that SAA administration significantly decreased infarction volume and vascular embolism, and ameliorated pathological injury in the hippocampus and striatum as well as the neurological deficits as compared with the model rats. Furthermore, we found that SAA administration significantly promoted neural stem/progenitor cells (NSPCs) proliferation, migration and differentiation into neurons, enhanced axonal regeneration and diminished neuronal apoptosis around the ipsilateral subventricular zone (SVZ), resulting in restored neural density and reconstructed neural circuits in the ischemic striatum. Moreover, we revealed that SAA-induced neurogenesis was associated to activating Wnt3a/GSK3β/β-catenin signaling pathway and downstream target genes in the hippocampus and striatum. Edaravone exerted equivalent inhibition on neuronal apoptosis in the SVZ, as SAA, but edaravone-induced neurogenesis was weaker than that of SAA. Taken together, our results demonstrate that long-term administration of SAA improves neurological function through enhancing endogenous neurogenesis and inhibiting neuronal apoptosis in ischemic stroke rats via activating Wnt3a/GSK3β/β-catenin signaling pathway. SAA may be a potential therapeutic drug to promote neurogenesis after stroke.

Application of Metabolomics to the Discovery of Biomarkers for Ischemic Stroke in the Murine Model: a Comparison with the Clinical Results

Ischemic stroke (IS) is a major cause of mortality and disability worldwide. However, the pathogenesis of IS remains unknown, and methods for early prediction and diagnosis of IS are lacking. Metabolomics can be applied to biomarker discovery and mechanism exploration of IS by exploring metabolic alterations. In this review, 62 IS metabolomics studies in the murine model published from January 2006 to December 2020 in the PubMed and Web of Science databases were systematically reviewed. Twenty metabolites (e.g., lysine, phenylalanine, methionine, tryptophan, leucine, lactate, serine, N-acetyl-aspartic acid, and glutathione) were reported consistently in more than two-third murine studies. The disturbance of metabolic pathways, such as arginine biosynthesis; alanine, aspartate and glutamate metabolism; aminoacyl-tRNA biosynthesis; and citrate cycle, may be implicated in the development of IS by influencing the biological processes such as energy failure, oxidative stress, apoptosis, and glutamate toxicity. The transient middle cerebral artery occlusion model and permanent middle cerebral artery occlusion model exhibit both common and distinct metabolic patterns. Furthermore, five metabolites (proline, serine, LysoPC (16:0), uric acid, glutamate) in the blood sample and 7 metabolic pathways (e.g., alanine, aspartate, and glutamate metabolism) are shared in animal and clinical studies. The potential biomarkers and related pathways of IS in the murine model may facilitate the biomarker discovery for early diagnosis of IS and the development of novel therapeutic targets.

Compatibility of ingredients of Danshen (Radix Salviae Miltiorrhizae) and Honghua (Flos Carthami) and their protective effects on cerebral ischemia-reperfusion injury in rats

Danshen (Radix Salviae Miltiorrhizae) and Honghua (Flos Carthami) (Danhong) are two drugs commonly prescribed together, which are often used in the treatment of cerebrovascular diseases in China. Due to the complexity of the ingredients of Danhong, the present study focused on performing the orthogonal compatibility method on the primary effective molecules of this drug: Tanshinol, salvianolic acid A, salvianolic acid B and hydroxysafflor yellow A. These four molecules were studied to determine their protective effects and to screen for the most compatible ingredients to improve cerebral ischemia-reperfusion injury (IR) in rats. Focal middle cerebral artery occlusion was performed to establish the cerebral IR model in rats. Male Sprague-Dawley rats were randomly divided into sham operation group, IR group and nine orthogonal administration groups with different ratios of Danhong effective ingredients and Danhong injection group. Neurological deficit score and cerebral infarction volume were measured postoperatively. Morphological pathological alterations were observed via H&E staining. Bcl-2 and Bax were quantified using ELISA. Immunohistochemistry was conducted to analyze the expression of caspase-3 in the hippocampus. The expression levels of cytochrome c, apoptotic peptidase activating factor 1 (apaf-1), caspase-9, caspase-3 and p53 mRNA in the hippocampus were assessed via reverse transcription-quantitative PCR. The results demonstrated that different compatibility groups significantly reduced the neurological function score and decreased the volume of cerebral infarct compared with the IR group. These groups were also indicated to improve the pathological damage to the brain tissue. In addition, certain compatibility groups significantly decreased the number of caspase-3 positive cells in the hippocampus and the expression levels of cytochrome c, apaf-1, caspase-9, caspase-3 and p53 mRNA in the brain tissue. Orthogonal group 4 (30 mg/kg tanshinol; 2.5 mg/kg salvianolic acid A; 16 mg/kg salvianolic acid B; 8 mg/kg hydroxysafflor yellow A) was indicated to be the most effective. The four effective ingredients of Danhong exhibited a protective effect on rats with cerebral IR injury, potentially through the inhibition of apoptosis via the downregulation of key targets upstream of the caspase-3 pathway. In addition, the present study provided novel insights for the continued study of the drug compatibility rules of TCM.

Integrated 16S rRNA Gene Sequencing and LC-MS Analysis Revealed the Interplay Between Gut Microbiota and Plasma Metabolites in Rats With Ischemic Stroke

Gut microbiome and plasma metabolome serve a role in the pathogenesis of ischemic stroke (IS). However, the relationship between the microbiota and metabolites remains unclear. This study aimed to reveal the specific asso-ciation between the microbiota and the metabolites in IS using integrated 16S rRNA gene sequencing and liquid chromatography-mass spectrometry (LC-MS) analysis. Male Sprague Dawley (SD) rats were divided into three groups: normal group (n = 8, Normal), model group (n = 9, IS), and sham-operated group (n = 8, Sham). Rats in the IS group were induced by middle cerebral artery occlusion (MCAO), and rats in the Sham group received an initial anesthesia and neck incision only. A neurological function test and 2,3,5-triphenyltetrazolium chloride (TTC) staining were used to assess the IS rat model. Then, the plasma samples were analyzed using untargeted LC-MS. The cecum samples were collected and analyzed using 16S rRNA sequencing. Pearson correlation analysis was performed to explore the association between the gut microbiota and the plasma metabolites. The 16S rRNA sequencing showed that the composition and diversity of the microbiota in the IS and control rats were significantly different. Compared with the Sham group, the abundance of the Firmicutes phylum was decreased, whereas Proteobacteria and Deferribacteres were increased in the IS group. Ruminococcus_sp_15975 and Lachnospiraceae_UCG_001 might be considered as biomarkers for the IS and Sham groups, respectively. LC-MS analysis revealed that many metabolites, such as L-leucine, L-valine, and L-phenylalanine, displayed different patterns between the IS and Sham groups. Pathway analysis indicated that these metabolites were mainly involved in mineral absorption and cholinergic synapse. Furthermore, integrated analysis correlated IS-related microbes with metabolites. For example, Proteobacteria were positively correlated with L-phenylalanine, while they were negatively correlated with eicosapentaenoic acid (EPA). Our results provided evidence of the relationship between the gut microbiome and plasma metabolome in IS, suggesting that these microflora-related metabolites might serve as potential diagnostic and therapeutic markers.

Neuroprotective Phytochemicals in Experimental Ischemic Stroke: Mechanisms and Potential Clinical Applications

Ischemic stroke is a challenging disease with high mortality and disability rates, causing a great economic and social burden worldwide. During ischemic stroke, ionic imbalance and excitotoxicity, oxidative stress, and inflammation are developed in a relatively certain order, which then activate the cell death pathways directly or indirectly via the promotion of organelle dysfunction. Neuroprotection, a therapy that is aimed at inhibiting this damaging cascade, is therefore an important therapeutic strategy for ischemic stroke. Notably, phytochemicals showed great neuroprotective potential in preclinical research via various strategies including modulation of calcium levels and antiexcitotoxicity, antioxidation, anti-inflammation and BBB protection, mitochondrial protection and antiapoptosis, autophagy/mitophagy regulation, and regulation of neurotrophin release. In this review, we summarize the research works that report the neuroprotective activity of phytochemicals in the past 10 years and discuss the neuroprotective mechanisms and potential clinical applications of 148 phytochemicals that belong to the categories of flavonoids, stilbenoids, other phenols, terpenoids, and alkaloids. Among them, scutellarin, pinocembrin, puerarin, hydroxysafflor yellow A, salvianolic acids, rosmarinic acid, borneol, bilobalide, ginkgolides, ginsenoside Rd, and vinpocetine show great potential in clinical ischemic stroke treatment. This review will serve as a powerful reference for the screening of phytochemicals with potential clinical applications in ischemic stroke or the synthesis of new neuroprotective agents that take phytochemicals as leading compounds.

Inhibition of TLR4/MAPKs Pathway Contributes to the Protection of Salvianolic Acid A Against Lipotoxicity-Induced Myocardial Damage in Cardiomyocytes and Obese Mice

The occurrence of lipotoxicity during obesity-associated cardiomyopathy is detrimental to health. Salvianolic acid A (SAA), a natural polyphenol extract of Salvia miltiorrhiza Bunge (Danshen in China), is known to be cardioprotective. However, its clinical benefits against obesity-associated cardiomyocyte injuries are unclear. This study aimed at evaluating the protective effects of SAA against lipotoxicity-induced myocardial injury and its underlying mechanisms in high fat diet (HFD)-fed mice and in palmitate-treated cardiomyocyte cells (H9c2). Our analysis of aspartate aminotransferase and creatine kinase isoenzyme-MB (CM-KB) levels revealed that SAA significantly reversed HFD-induced myocardium morphological changes and improved myocardial damage. Salvianolic acid A pretreatment ameliorated palmitic acid-induced myocardial cell death and was accompanied by mitochondrial membrane potential and intracellular reactive oxygen species improvement. Analysis of the underlying mechanisms showed that SAA reversed myocardial TLR4 induction in HFD-fed mice and H9c2 cells. Palmitic acid-induced cell death was significantly reversed by CLI-95, a specific TLR4 inhibitor. TLR4 activation by LPS significantly suppressed SAA-mediated lipotoxicity protection. Additionally, SAA inhibited lipotoxicity-mediated expression of TLR4 target genes, including MyD88 and p-JNK/MAPK in HFD-fed mice and H9c2 cells. However, SAA did not exert any effect on palmitic acid-induced SIRT1 suppression and p-AMPK induction. In conclusion, our data shows that SAA protects against lipotoxicity-induced myocardial damage through a TLR4/MAPKs mediated mechanism.

Biliverdin Protects Against Cerebral Ischemia/Reperfusion Injury by Regulating the miR-27a-3p/Rgs1 Axis

BACKGROUND

We have previously demonstrated that biliverdin has neuroprotective effects that ameliorate cerebral ischemia/reperfusion (I/R) injury in rats. However, the underlying mechanism is unknown. This study aimed at elucidating on the modulatory role of miR-27a-3p on Rgs1 as a mechanism by which biliverdin affects cerebral I/R injury.

METHODS

Middle cerebral artery occlusion/reperfusion (MCAO/R) was used to establish I/R rat models while oxygen glucose deprivation/reoxygenation (OGD/R) was used to induce hippocampal neurons to establish I/R models in vitro. Infarct volume was assessed by TTC staining. Apoptotic analyses of ischemic cortical neurons and cells were performed by TUNEL staining and flow cytometry, respectively. Cell viability was assessed by the CCK-8 assay while the target of miR-27a-3p was determined by double luciferase reporter assay. Relative expression levels of miR-27a-3p and Rgs1 (in vivo and in vitro) as well as markers of inflammation and apoptosis (in vitro) were detected by RT-qPCR. Then, Elisa and western blot were used to assess protein expression levels of inflammatory and apoptotic markers in vitro.

RESULTS

Biliverdin suppressed inflammation and apoptosis in hippocampal neurons upon OGD/R, and reduced cerebral infarction volume as well as apoptosis in the MCAO/R rat model. Furthermore, biliverdin upregulated miR-27a-3p and downregulated hippocampal neuron Rgs1 after OGD/R as well as in rat brain tissues after cerebral I/R. Bioinformatic analysis revealed an miR-27a-3p docking site in the 3'-UTR region of Rgs1. Luciferase reporter assays showed that Rgs1 is an miR-27a-3p target. Moreover, miR-27a-3p upregulation inhibited OGD/R-triggered inflammation and suppressed neuronal apoptosis. Rgs1 knockdown suppressed OGD/R-triggered inflammation and decreased neuronal apoptosis while miR-27a-3p downregulation reversed the protective effect of Rgs1 knockdown. Moreover, miR-27a-3p overexpression and Rgs1 silencing suppressed NF-κB (p65) expression.

CONCLUSION

Biliverdin protects against cerebral I/R injury by regulating the miR-27a-3p/Rgs1 axis, thereby inhibiting inflammation and apoptosis.

The efficacy and safety of salvianolic acids on acute cerebral infarction treatment: A protocol for systematic review and meta analysis

BACKGROUND

Salvianolic acids (SA) has been widely used for the treatment of acute cerebral infarction (ACI) combined with basic western medicine therapy in China. This study was aimed to evaluate the efficacy and safety of SA on ACI treatment and its influence on neurological functions, activity of daily living, and cognitive functions.

METHODS

We retrieved related articles from PubMed, the Cochrane Center Controlled Trials Register, EMBASE, Medline, Ovid, Chinese National Knowledge Infrastructure, Chinese Biomedical Literature Database, and Wanfang Database without date and language restrictions. Finally, 58 randomized controlled trials were included from 239 retrieved records. Two researchers extracted the basic information and data from included articles and assessed the quality and analysis of data by using Review Manager 5.3.

RESULTS

The administration of SA significantly increased the total clinical effective rate of ACI treatment (P < .001) and improved the National Institute of Health Stroke Scale scores, modified Rankin Scale scores, and Barthel Index scores after treatment and 3 months after ACI (P < .05). The activities of daily living scores in the SA group were significantly increased after treatment (P < .001), whereas they were remarkably decreased 3 months after ACI (P < .001) compared with that in the control group. Besides, SA profoundly promoted the recovery of Montreal Cognitive Assessment scores (P < .001). However, the use of SA increased the risk of adverse events occurrence (P = .007).

CONCLUSION

SA combined with basic western medicine treatment could promote neurological functions, daily living activities, and cognitive functions recovery of ACI patients. Although SA increased the risk of adverse events occurrence, these adverse events were easily controlled or disappeared spontaneously.

Therapeutic targets of oxidative/nitrosative stress and neuroinflammation in ischemic stroke: Applications for natural product efficacy with omics and systemic biology

Oxidative/nitrosative stress and neuroinflammation are critical pathological processes in cerebral ischemia-reperfusion injury, and their intimate interactions mediate neuronal damage, blood-brain barrier (BBB) damage and hemorrhagic transformation (HT) during ischemic stroke. We review current progress towards understanding the interactions of oxidative/nitrosative stress and inflammatory responses in ischemic brain injury. The interactions between reactive oxygen species (ROS)/reactive nitrogen species (RNS) and innate immune receptors such as TLR2/4, NOD-like receptor, RAGE, and scavenger receptors are crucial pathological mechanisms that amplify brain damage during cerebral ischemic injury. Furthermore, we review the current progress of omics and systematic biology approaches for studying complex network regulations related to oxidative/nitrosative stress and inflammation in the pathology of ischemic stroke. Targeting oxidative/nitrosative stress and neuroinflammation could be a promising therapeutic strategy for ischemic stroke treatment. We then review recent advances in discovering compounds from medicinal herbs with the bioactivities of simultaneously regulating oxidative/nitrosative stress and pro-inflammatory molecules for minimizing ischemic brain injury. These compounds include sesamin, baicalin, salvianolic acid A, 6-paradol, silymarin, apocynin, 3H-1,2-Dithiole-3-thione, (-)-epicatechin, rutin, Dl-3-N-butylphthalide, and naringin. We finally summarize recent developments of the omics and systematic biology approaches for exploring the molecular mechanisms and active compounds of Traditional Chinese Medicine (TCM) formulae with the properties of antioxidant and anti-inflammation for neuroprotection. The comprehensive omics and systematic biology approaches provide powerful tools for exploring therapeutic principles of TCM formulae and developing precision medicine for stroke treatment.

Salvianolic acid A increases the accumulation of doxorubicin in brain tumors through Caveolae endocytosis

Brain glioma is one of the most common brain tumors in the central nervous system (CNS). The blood-brain tumor barrier (BTB) restricts the delivery of anti-tumor drugs into tumor tissue in the brain. Therefore, improving the transportation of antineoplastic drugs across the BTB is essential to ameliorate treatment of brain tumors. The present study was performed to explore the effect and mechanism of salvianolic acid A (Sal A) on transportation of doxorubicin (Dox) across the BTB in vivo and in vitro. By creating a brain C6 glioma model in rats, we demonstrated that Sal A significantly increased the level of Dox in brain tumor tissue as shown by liquid chromatograph mass spectrometry. Interestingly, we found that Sal A increased transendothelial electrical resistance (TEER) values of the BTB and decreased the permeability of FITC-Dextran (4kD) across the BTB in vitro. Furthermore, the expression of tight junction proteins (TJs) in glioma endothelial cells (GECs) and brain tumor microvessels were also increased, suggesting that Sal A enhanced delivery of Dox across the BTB independent of the paracellular pathway. Next, we detected that Sal A had an effect on transcellular transport of compounds across the BTB. The accumulation of FITC-labeled bovine serum albumin (FITC-BSA) was significantly increased in GECs after treatment with Sal A (10 μM) for 6h, which was inhibited after pre-treatment with methyl-β-cyclodextrin (MβCD) for 30 min. The increased delivery of Dox across the BTB was also reduced after treatment with MβCD. In addition, phosphorylation levels of protein kinase B (PKB) and tyrosine protein kinase-Src family (Src) were increased in the Sal A treatment group. Sal A up-regulated the expression level of the phosphorylation of Caveolin-1 (pCaveolin-1), and this effect was reversed by a PKB or Src inhibitor. Taken together, our study showed for the first time that Sal A facilitated the delivery of antitumor drugs into brain tumor tissues by targeting the PKB/Src/Caveolin-1 signaling pathway.

Comparative Pharmacokinetics of Hydrophilic Components in Salvia miltiorrhiza Bge. and Carthamus tinctorius L. in Rats That Underwent Cerebral Ischemia Reperfusion Using an HPLC-DAD Method

Background

In China, the combination of herb Salvia miltiorrhiza Bge. (Danshen) and Carthamus tinctorius L. (Honghua) is an effective treatment for stroke. A previous study showed that the combination of four herbal components: danshensu (DSS), hydroxysafflor yellow A (HSYA), salvianolic acid A (SAA), and salvianolic acid B (SAB) was effective for treatment of cerebral ischemia-reperfusion (I/R) injury in rats. However, the pharmacokinetic characteristics of this formula require further investigation. The present study investigated the pharmacokinetic differences between each component of in two formulas in cerebral I/R injury rats. The influencing factors may affect the compatibility of components were analyzed.

Methods

Focal cerebral I/R was induced by middle cerebral artery occlusion (MCAO). Rats that underwent MCAO were randomly divided into two groups and administered treatments through the tail vein. Blood samples were collected at predetermined time points following administration. The concentrations of DSS, HSYA, SAB, and SAA in rat plasma were determined using HPLC-DAD, and the main pharmacokinetic parameters were calculated. Pharmacokinetic parameters were calculated using DAS 3.2.6 software and SPSS 23.0 statistical analysis software.

Results

Our results showed that DSS, HSYA, SAB, and SAA in MCAO model rats had statistically significant differences in two formulas. For DSS and SAA, pharmacokinetic parameters with statistically significant differences including AUC_(0−t), AUMC_(0−t), MRT_(0−t), VRT_(0−t), t_1/2z, V_z, CL_z, and C_max (P < 0.01). For HSYA, significant differences in the parameters including AUC_(0−t), AUMC_(0−t), MRT_(0−t), VRT_(0−t) (P < 0.01), CL_z and C_max (P < 0.05).

Conclusion

The difference in pharmacokinetic parameters in response to each component may have been due to differences in the dosages of the components (HSYA, SAA, SAB) and the compatibility of components. Meanwhile, there were many influencing factors could affect the compatibility of components, such as the metabolism by CYP450 enzymes, plasma protein binding rates, and effects related to the blood-brain barrier (BBB). Moreover, our study provided new insights, such as choosing appropriate dosages of active components of traditional Chinese medicine (TCM) to aid in prevention and treatment of cerebral ischemic diseases. The method and results in this study could provide a foundation for future pharmacological studies of the active components in Danshen and Honghua.

Salvianolic Acid D Alleviates Cerebral Ischemia-Reperfusion Injury by Suppressing the Cytoplasmic Translocation and Release of HMGB1-Triggered NF-κB Activation to Inhibit Inflammatory Response

Inflammatory response participates in the overall pathophysiological process of stroke. It is a promising strategy to develop antistroke drugs targeting inflammation. This study is aimed at investigating the therapeutic effect and anti-inflammatory mechanism of salvianolic acid D (SalD) against cerebral ischemia/reperfusion (I/R) injury. A rat middle cerebral artery occlusion/reperfusion (MCAO/R) injury model was established, and an oxygen-glucose deprivation/reoxygenation (OGD/R) injury model was established in PC12 cells. Neurological deficit score, cerebral infarction, and edema were studied in vivo. Cell viability was achieved using the MTT method in vitro. The Bax, Bcl-2, cytochrome c, HMGB1, TLR4, TRAF6, NF-κB p65, p-NF-κB p65, and cleaved caspase-3 and -9 were tested via the Western blot method. Cytokines and cytokine mRNA, including TNF-α, IL-1β, and IL-6, were studied via ELISA and PCR methods. The translocation of HMGB1 and NF-κB were studied by immunofluorescence assay. The HMGB1/NeuN, HMGB1/GFAP, and HMGB1/Iba1 double staining was carried out to observe the localization of HMGB1 in different cells. Results showed that SalD alleviated neurological impairment, decreased cerebral infarction, and reduced edema in I/R rats. SalD improved OGD/R-downregulated PC12 cell viability. SalD also promoted Bcl-2 expression and suppressed Bax, cytochrome c, and cleaved caspase-3 and -9 expression. SalD decreased the intensity of TLR4, MyD88, and TRAF6 proteins both in vivo and in vitro, and significantly inhibited the NF-κB nuclear translocation induced by I/R and OGD/R. What's more, SalD inhibited HMGB1 cytoplasmic translocation in neurons, astrocytes, and microglia in both the cortex and hippocampus regions of I/R rats. In conclusion, SalD can alleviate I/R-induced cerebral injury in rats and increase the PC12 cell viability affected by OGD/R. The anti-inflammatory mechanism of SalD might result from the decreased nuclear-to-cytoplasmic translocation of HMGB1 and the inhibition on its downstream TLR4/MyD88/NF-κB signaling.

Chemical and pharmacological research on the polyphenol acids isolated from Danshen: A review of salvianolic acids

Danshen, the dried root of Salvia miltiorrhiza Bge, is a common medicinal herb in Traditional Chinese Medicine, which has been used for the treatment of a number of diseases for thousands of years. More than 2000 years ago, the Chinese early pharmacy monograph "Shennong Materia Medica" recorded that Danshen could be used for the treatment of gastrointestinal diseases, cardiovascular diseases, certain gynecological diseases, etc. Since then, Danshen has been widely used clinically in many different prescriptions for many different diseases, especially for the treatment of cardiovascular diseases. Nowadays, many pharmacological studies about the water-soluble components from Danshen have been reported, especially salvianolic acids. It turned out that salvianolic acids showed strong anti-lipid peroxidation and anti-thrombic activities, and among them, SalAA and SalAB were the most potent. This review focused on the achievements in research of salvianolic acids regarding their bioactivities and pharmacological effects. These studies not only shed light on the water-soluble active components of Danshen and their mechanisms at the molecular level, but also provided theoretical information for the development of new medicines from Danshen for the treatment of cardiovascular and cerebrovascular diseases, inflammatory diseases, metabolic diseases, etc.

Salvianolic acid a inhibits platelet activation and aggregation in patients with type 2 diabetes mellitus

Background

Platelets in patients with type 2 diabetes mellitus (DM2) are characterized by increased activation and aggregation, which tends to be associated with a high morbidity and mortality due to cardiovascular disease (CVD). Moreover, a large proportion of DM2 patients show an inadequate response to standard antiplatelet treatments, contributing to recurrent cardiovascular events. In our previous study, we indicated that Salvianolic acid A (SAA) presents an antiplatelet effect in healthy volunteers. However, whether it can inhibit “activated platelets” with a pathologic status has not been explored. Therefore, this study was designed to investigate the antiplatelet effect of SAA and its diabetic complication-related difference in DM2.

Methods

Forty patients diagnosed with DM2 from January 2018 to April 2018 were recruited. Fibrinogen-binding (PAC-1) and P-selectin (CD62p) flow cytometry reagents were measured under resting and stimulated conditions by flow cytometry, while agonist-induced platelet aggregation was conducted by light transmission aggregometry. Before all these measurements were conducted, all platelet samples were preincubated with a vehicle or SAA for 10 min. Additionally, the diabetic complication-related difference in the antiplatelet effect of SAA was further studied in enrolled patients.

Results

The expressions of PAC-1 and CD62p were elevated in DM2, as well as the maximal platelet aggregation. In addition, SAA decreased the expressions of PAC-1 and CD62p, which were enhanced by ADP and thrombin (all P < 0.01). It also reduced the platelet aggregation induced by ADP (P < 0.001) and thrombin (P < 0.05). Comparing the antiplatelet effect of SAA on DM2, with and without diabetic complications, no statistically significant difference was found (all P > 0.05).

Conclusions

The present study demonstrated that SAA can inhibit platelet activation and aggregation in patients with DM2, and the inhibition did not abate for the existence of diabetic complications.

Pharmacokinetics of Active Ingredients of Salvia miltiorrhiza and Carthamus tinctorius in Compatibility in Normal and Cerebral Ischemia Rats: A Comparative Study

Background and Objective

Dan-Hong injection, which comprises extracts of Salvia miltiorrhiza and Carthamus tinctorius, promotes blood circulation and reduces blood stasis. Combination of S. miltiorrhiza and C. tinctorius is more effective in treating cerebral ischemia than S. miltiorrhiza alone. This study aimed to examine the pharmacokinetic characteristics of four active ingredients of S. miltiorrhiza and C. tinctorius, namely danshensu (DSS), hydroxysafflor yellow A (HSYA), and salvianolic acid A (SAA) and B (SAB) in normal and cerebral ischemia rats.

Methods

Normal and cerebral ischemia rats were injected via the tail vein with each active ingredient, and blood was collected through the jaw vein at different time points. The plasma concentration of the compatibility group was analyzed by high-performance liquid chromatography, and pharmacokinetic parameters were determined using Pharmacokinetic Kinetica 4.4 software.

Results

The pharmacokinetics of the four active ingredients in the normal and cerebral ischemia rats were consistent with a two-compartment model. The area under the concentration–time curve was higher in normal rats than in cerebral ischemia rats, with a highly significant difference for SAA (P < 0.01). Clearance rates were lower in normal rats than in cerebral ischemia rats, with DSS showing the most significant difference (P < 0.01). Furthermore, there were significant differences between normal and cerebral ischemia rats in the distribution phase-elimination half life for DSS, SAA, and HSYA, as well as in the apparent volume of distribution for the central compartment for DSS and HSYA (P < 0.01). The plasma concentrations of the four active ingredients were higher in normal rats than in cerebral ischemia rats.

Conclusion

Cerebral ischemia rats showed higher drug clearance rates and longer retention times than normal rats, which may be due to destruction of the blood–brain barrier during cerebral ischemia–reperfusion. The four active ingredients likely integrated and interacted with each other to affect target sites in the brain to protect against cerebral ischemic injury.

Elaboration of the Comprehensive Metabolic Profile of Salvianolic Acid A in Vivo and in Vitro Using UFLC-Q/TOF-MS

Salvianolic acid A (Sal A) has a wide range of pharmacological activities. To date, there have been no systematic and detailed metabolite research data of Sal A after oral administration in vitro and in vivo. In this study, a rapid and systematic method based on ultrafast liquid chromatography-quadrupole-time-of-flight mass spectrometry was developed to detect metabolites of Sal A in vitro (human liver microsome, human intestinal microbiota, artificial gastric, and intestinal juice) and in vivo (urine, plasma, feces, and various organs collected after oral administration of Sal A to normal rats and pseudo-germ-free rats). A total of 26 metabolites of Sal A were characterized. These metabolites were formed through extensive metabolic reactions, such as hydroxylation, hydrogenation, and glucuronidation reactions. This study provides novel possibility for exploring the potential biological mechanism of Sal A, and aids the promotion of clinical application.

Inhibition of FOXO3a/BIM signaling pathway contributes to the protective effect of salvianolic acid A against cerebral ischemia/reperfusion injury

Salvianolic acid A (SalA) is an effective compound extracted from traditional Chinese medicine Salvia miltiorrhiza Bunge. The Forkhead box O3a (FOXO3a) signaling pathway plays crucial roles in the modulation of ischemia-induced cell apoptosis. However, no information about the regulatory effect of SalA on FoxO3a is available. To explore the anti-cerebral ischemia effect and clarify the therapeutic mechanism of SalA, SH-SY5Y cells and Sprague–Dawley rats were applied, which were exposed to oxygen glucose deprivation/reoxygenation (OGD/R) and middle cerebral artery occlusion/reperfusion (MCAO/R) injuries, respectively. The involved pathway was identified using the specific inhibitor LY294002. Results showed that SalA concentration-dependently inhibited OGD/R injury triggered cell viability loss. SalA reduced cerebral infarction, lowered brain edema, improved neurological function, and inhibited neuron apoptosis in MCAO/R rats, which were attenuated by the treatment of phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) specific inhibitor LY294002. SalA time- and concentration-dependently upregulated the phosphorylation levels of protein kinase B (AKT) and its downstream protein FOXO3a. Moreover, the nuclear translocation of FOXO3a was inhibited by SalA both in vivo and in vitro, which was also reversed by LY294002. The above results indicated that SalA fought against ischemia/reperfusion damage at least partially via the AKT/FOXO3a/BIM pathway.

Some pharmacokinetic parameters of salvianolic acid A following single-dose oral administration to rats

CONTEXT

Salvianolic acid A (Sal A) is a hydrophilic bioactive compound isolated from Salvia miltiorrhiza Bunge (Lamiaceae). It exerts beneficial effects after oral administration on diabetic complications.

OBJECTIVE

To systematically study the absorption, distribution and excretion of Sal A after single-dose oral administration.

MATERIALS AND METHODS

Animal experiments were conducted in Sprague-Dawley rats. Plasma was sampled at designated times after oral doses of 5, 10 and 20 mg/kg, and an intravenous dose of 50 μg/kg. Tissues were harvested at 10, 60 and 120 min postdosing. Bile, urine and feces were collected at specified intervals before and after dosing. Absorption and distribution characteristics were analyzed by LC-MS, and excretion characteristics were analyzed by UPLC-MS/MS. The Caco-2 cell model was applied to investigate potential mechanisms.

RESULTS

The C_max (5 mg/kg: 31.53 μg/L; 10 mg/kg: 57.39 μg/L; 20 mg/kg: 111.91 μg/L) of Sal A increased linearly with doses (r> 0.99). The calculated absolute bioavailability was 0.39-0.52%. Transport experiment showed poor permeability and the ratio of P_B-A to P_A-B was 3.13-3.97. The highest concentration of Sal A was achieved in stomach followed by small intestine and liver, and it could also be detected in brain homogenate. Approximately 0.775% of its administered dose was excreted via feces, followed by bile (0.00373%) and urine (0.00252%).

DISCUSSION AND CONCLUSIONS

These results support the future development of Sal A as an oral drug for the treatment of diabetic complications. Future research should be conducted to investigate the reason for its poor bioavailability and improve this situation.

HX600, a synthetic agonist for RXR-Nurr1 heterodimer complex, prevents ischemia-induced neuronal damage

Ischemic stroke is amongst the leading causes of death and disabilities. The available treatments are suitable for only a fraction of patients and thus novel therapies are urgently needed. Blockage of one of the cerebral arteries leads to massive and persisting inflammatory reaction contributing to the nearby neuronal damage. Targeting the detrimental pathways of neuroinflammation has been suggested to be beneficial in conditions of ischemic stroke. Nuclear receptor 4A-family (NR4A) member Nurr1 has been shown to be a potent modulator of harmful inflammatory reactions, yet the role of Nurr1 in cerebral stroke remains unknown. Here we show for the first time that an agonist for the dimeric transcription factor Nurr1/retinoid X receptor (RXR), HX600, reduces microglia expressed proinflammatory mediators and prevents inflammation induced neuronal death in in vitro co-culture model of neurons and microglia. Importantly, HX600 was protective in a mouse model of permanent middle cerebral artery occlusion and alleviated the stroke induced motor deficits. Along with the anti-inflammatory capacity of HX600 in vitro, treatment of ischemic mice with HX600 reduced ischemia induced Iba-1, p38 and TREM2 immunoreactivities, protected endogenous microglia from ischemia induced death and prevented leukocyte infiltration. These anti-inflammatory functions were associated with reduced levels of brain lysophosphatidylcholines (lysoPCs) and acylcarnitines, metabolites related to proinflammatory events. These data demonstrate that HX600 driven Nurr1 activation is beneficial in ischemic stroke and propose that targeting Nurr1 is a novel candidate for conditions involving neuroinflammatory component.

Effects of salvianolic acid on cerebral perfusion in patients after acute stroke: A single-center randomized controlled trial

Hypoperfusion following acute stroke is common in the infarct core and periphery tissues. The present study evaluated the efficacy of salvianolic acid (SA) on the cerebral perfusion of patients who had suffered from acute stroke using perfusion-weighted magnetic resonance imaging (PWI) to examine the blood perfusion of the affected brain tissue prior to and following treatment. Patients who were admitted to PLA 153 Central Hospital within 72 h of acute stroke symptom onset and had a Glasgow coma scale ≥5 were randomized into two groups: SA and control groups. Patients in the SA group were administered SA 0.13 g/day for 14 days. PWI was performed for all patients at admission and post-treatment. The National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) were applied to assess neurological function at admission and 3 months post treatment. A total of 159 patients were enrolled (85 patients in the SA group and 74 patients in the control group). A total of 62 patients in the SA group and 51 patients in the control group exhibited hypoperfusion in the ipsihemisphere of the diffusion-weighted magnetic resonance imaging (DWI) lesion. In addition, relative cerebral blood volume (rCBV), a ratio of the signal value of the region of interest in the same hemisphere of the DWI lesion to that of its mirror in the PWI CBV map, decreased significantly following treatment with SA compared with the control group in patients with hypoperfusion (P=0.02), which were indicated by PWI images at admission, in the DWI lesions or the surrounding areas. Additionally, there was no significant difference in patients with normal perfusion at admission in rCBV in DWI lesions or its surrounding area between the two groups at day 15. However, a significant improvement in NIHSS (P=0.001) and mRS (P=0.005) was indicated in the SA group compared with the control at day 90. The present study indicated that SA may improve the neurological dysfunction of patients with acute stroke, which may be explained by the increased perfusion of hypoperfused brain tissues.

Molecular Pharmacology of Rosmarinic and Salvianolic Acids: Potential Seeds for Alzheimer's and Vascular Dementia Drugs

Both caffeic acid and 3,4-dihydroxyphenyllactic acid (danshensu) are synthesized through two distinct routs of the shikimic acid biosynthesis pathway. In many plants, especially the rosemary and sage family of Lamiaceae, these two compounds are joined through an ester linkage to form rosmarinic acid (RA). A further structural diversity of RA derivatives in some plants such as Salvia miltiorrhiza Bunge is a form of RA dimer, salvianolic acid-B (SA-B), that further give rise to diverse salvianolic acid derivatives. This review provides a comprehensive perspective on the chemistry and pharmacology of these compounds related to their potential therapeutic applications to dementia. The two common causes of dementia, Alzheimer's disease (AD) and stroke, are employed to scrutinize the effects of these compounds in vitro and in animal models of dementia. Key pharmacological mechanisms beyond the common antioxidant and anti-inflammatory effects of polyphenols are highlighted with emphasis given to amyloid beta (Aβ) pathologies among others and neuronal regeneration from stem cells.