Effect of Buyang Huanwu decoction on amino acid content in cerebrospinal fluid of rats during ischemic/reperfusion injury

Buyang huanwu decoction alleviates stroke-induced immunosuppression in MCAO mice by reducing splenic T cell apoptosis triggered by AIM2 inflammasome

ETHNOPHARMACOLOGICAL RELEVANCE

Ischemic stroke is a serious disabling and fatal disease that places a heavy burden on the world. Stroke induces a state of systemic immunosuppression that is strongly associated with an increased risk of infection and severe outcomes. Buyang Huanwu Decoction (BYHWD) is an ancient Chinese traditional formula with a good clinical and experimental basis. However, the role of BYHWD on post-stroke immunomodulation, especially immunosuppression, is unclear.

AIM OF THE STUDY

The aim of this study was to investigate the pharmacological mechanism of BYHWD to alleviate ischemic stroke by analyzing splenic T cells apoptosis triggered by the AIM2 inflammasome activation cascade.

MATERIALS AND METHODS

An ischemic stroke model in C57BL/6 J mice was constructed using the MCAO method. The mNSS test and the hanging wire test were conducted to evaluate neurological impairment in mice. Histopathological damage was visualized by Nissl staining and HE staining. The protective effects of BYHWD on the spleen were determined by splenic index and spleen HE staining. The inhibition of AIM2 inflammasome cascade by BYHWD were explored through immunofluorescence (IF), flow cytometry, enzyme-linked immunosorbent assay (ELISA) and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Flow cytometry was used to assess the apoptosis of splenic T cells.

RESULTS

BYHWD significantly reduced infarct size, improved neurological function scores, and alleviated histopathological damage in middle cerebral artery occlusion (MCAO) mice. At the same time, BYHWD salvaged spleen atrophy. BYHWD significantly ameliorated apoptosis of splenic T lymphocytes. Key proteins and factors in the AIM2/IL-1β/FasL/Fas axis are effectively inhibited from expression after BYHWD treatment.

CONCLUSION

It is the first study to demonstrate that BYHWD can improve stroke-induced immunosuppression by down-regulating Fas-dependent splenic T-cell apoptosis triggered by peripheral AIM2 inflammasome-driven signaling cascade.

Buyang Huanwu Decoction suppresses cardiac inflammation and fibrosis in mice after myocardial infarction through inhibition of the TLR4 signalling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

It has been reported that cardiac inflammation and fibrosis participate in the development of heart failure (HF) following myocardial infarction (MI). Anti-inflammatory and anti-fibrotic treatments exhibit therapeutic efficacy in MI. Buyang Huanwu Decoction (BYHWD) has cardioprotective properties. However, whether BYHWD regulates cardiac inflammation and fibrosis in HF after MI, and the underlying mechanisms, are still unknown.

AIM OF THE STUDY

This study aimed to explore the effects and potential mechanisms of BYHWD on cardiac inflammation and fibrosis after MI.

MATERIALS AND METHODS

An MI model was constructed through ligation of the left anterior descending coronary artery (LAD) in mice. The cardioprotective effects of BYHWD were determined by echocardiography, Masson trichrome staining, wheat germ agglutinin (WGA) staining and haematoxylin and eosin (HE) staining. The effects of BYHWD on inflammation and fibrosis, and on the TLR4 signalling pathway, were explored through immunohistochemistry (IHC), Western blot (WB), enzyme-linked immunosorbent assay (ELISA) and quantitative reverse transcription polymerase chain reaction (qRT-PCR) in vivo. Next, the effects of BYHWD on primary cardiac fibroblasts (CFs) inflammation and collagen synthesis, and on the TLR4 signalling pathway, were detected using WB, immunofluorescence (IF) and qRT-PCR in vitro. In addition, the suppression and overexpression of TLR4 in CFs were further explored.

RESULTS

BYHWD dose-dependently reduced cardiac inflammation, fibrosis and ventricular dysfunction. The expression levels of collagen Ⅰ/Ⅲ, IL-1β and IL-18, as well as critical proteins in the TLR4 signalling pathway and the NLRP3 inflammasome, were suppressed by BYHWD in the in vivo experiment. BYHWD inhibited CFs inflammation and collagen synthesis, as well as critical proteins in the TLR4 signalling pathway and the NLRP3 inflammasome, in the in vitro experiment. TLR4 suppression mitigated these inhibitory effects of BYHWD while overexpression of TLR4 markedly reversed these inhibitory effects of BYHWD.

CONCLUSION

BYHWD exerts anti-inflammatory and anti-fibrotic effects in mice after MI, and suppresses CFs inflammation and collagen synthesis through suppression of the TLR4 signalling pathway.

Evaluating the Diagnostic Value of Electrovestibulography (EVestG) in Alzheimer's Patients with Mixed Pathology: A Pilot Study

Background and Objectives: Diagnosis of dementia subtypes caused by different brain pathophysiologies, particularly Alzheimer's disease (AD) from AD mixed with levels of cerebrovascular disease (CVD) symptomology (AD-CVD), is challenging due to overlapping symptoms. In this pilot study, the potential of Electrovestibulography (EVestG) for identifying AD, AD-CVD, and healthy control populations was investigated. Materials and Methods: A novel hierarchical multiclass diagnostic algorithm based on the outcomes of its lower levels of binary classifications was developed using data of 16 patients with AD, 13 with AD-CVD, and 24 healthy age-matched controls, and then evaluated on a blind testing dataset made up of a new population of 12 patients diagnosed with AD, 9 with AD-CVD, and 8 healthy controls. Multivariate analysis was run to test the between population differences while controlling for sex and age covariates. Results: The accuracies of the multiclass diagnostic algorithm were found to be 85.7% and 79.6% for the training and blind testing datasets, respectively. While a statistically significant difference was found between the populations after accounting for sex and age, no significant effect was found for sex or age covariates. The best characteristic EVestG features were extracted from the upright sitting and supine up/down stimulus responses. Conclusions: Two EVestG movements (stimuli) and their most informative features that are best selective of the above-populations' separations were identified, and a hierarchy diagnostic algorithm was developed for three-way classification. Given that the two stimuli predominantly stimulate the otholithic organs, physiological and experimental evidence supportive of the results are presented. Disruptions of inhibition associated with GABAergic activity might be responsible for the changes in the EVestG features.

Study on the action mechanism of Buyang Huanwu Decoction against ischemic stroke based on S1P/S1PR1/PI3K/Akt signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Ischemic stroke is a common and frequent clinical disease. Recent studies have demonstrated that sphingolipid plays an important role in the pathological process of ischemic stroke. PI3K-Akt is a classic protective signaling pathway of cerebral ischemic injury. After acting on the S1P receptor, S1P can activate the downstream PI3K/Akt signaling pathway and play an anti-cerebral ischemia role. Buyang Huanwu Decoction (BHD) is a traditional Chinese medicine formula used to treat ischemic stroke. However, the mechanisms of BHD on ischemic stroke remain unclear based on S1P/S1PR1/PI3K/Akt signaling pathway.

AIM OF THE STUDY

The present study is intended to investigate the action mechanism of BHD on ischemic stroke based on the S1P/S1PR1/PI3K/Akt signaling pathway from multiple perspectives.

MATERIALS AND METHODS

The BHD lyophilized product was prepared by vacuum freeze-drying method, of which the chemical composition was determined by UPLC-Q-TOF/MS. The mouse permanent middle cerebral artery occlusion (pMCAO) model was established by the suture-occluded method. Male KM mice were randomly divided into seven groups: sham group, model group, FTY720 (positive control) group, BHD group, BHD + W146 (selective S1PR1 inhibitor) group, SEW2871 (selective S1PR1 agonist) group, and Calycosin group. Each group was administered continuously for 14 days and evaluated with modified neurological severity score (mNSS) and cerebral infarct volume on the 1st, 4th, 7th, and 14th days. The SphK1, SphK2, S1PR1, PI3K, Akt, and p-Akt protein in the prefrontal lobe, hippocampus, and striatum was quantified by Western blot and immunohistochemical (IHC) experiment respectively. The qRT-PCR method was employed to evaluate SphK1, SphK2, and S1PR1 mRNA expression in the above tissue.

RESULTS

BHD and Calycosin both effectively improved mNSS scores with smaller infarct volumes. The SphK1 level in the prefrontal lobe, hippocampus, and striatum of mice in the BHD group was significantly lower, and SphK2, PI3K, and p-Akt in the hippocampus and striatum were significantly higher than those in the model group. BHD significantly decreased SphK1 mRNA expression in the prefrontal lobe, hippocampus, and striatum, and significantly up-regulated SphK2 mRNA and S1PR1 mRNA expression. Additionally, SphK1 protein expression levels of the prefrontal lobe, hippocampus, and striatum in the BHD group was significantly lower than model group, and SphK2, S1PR1, PI3K, Akt, and p-Akt protein expressions levels were increased obviously. Furthermore, SEW2871 can increase S1PR1 and Akt expression, and up-regulate SphK2 and S1PR1 mRNA expression. The effect of BHD on the expression of S1P/S1PR1/PI3K/Akt signaling pathway-related proteins and mRNA were weakened by BHD + W146.

CONCLUSION

BHD and Calycosin significantly improved the symptoms of neurological deficits in pMCAO mice, reduced the cerebral infarction volume, up-regulated SphK2 and S1PR1 mRNA levels, enhanced SphK2, S1PR1, PI3K, Akt, p-Akt protein expression of the prefrontal lobe, hippocampus and striatum, and down-regulated SphK1 mRNA and protein expression, which may be helpful to clarify the mechanism of BHD through S1P/S1PR1/PI3K/Akt signaling pathway to protect against cerebral ischemic injury.

Buyang Huanwu decoction alleviates oxidative injury of cerebral ischemia-reperfusion through PKCε/Nrf2 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Ischemic stroke is a significant risk factor for human health, and Buyang Huanwu Decoction is a classical and famous Chinese formula for treating it, but without clear pharmacological mechanism.

AIM OF THE STUDY

The aim of this study was to investigate that the molecular mechanism of BYHWD activation of the PKCε/Nrf2 signaling pathway to attenuate cerebral ischemia-reperfusion (I/R) oxidative damage.

MATERIALS AND METHODS

The MCAO method was used to establish a brain I/R injury model in SD rats, and neurological deficits were evaluated by neurological function score. Neuronal damage was observed by Nissl staining and immunofluorescence detection of MAP2 expression. Oxidative damage was observed by ROS, SOD, GSH-PX, MDA, and 8-OHdG. Changes in mitochondrial membrane potential were detected by using the fluorescent probe JC-1. The Western blot analysis detected protein expression of PKCε, P-PKCε, total Nrf2, nuclear Nrf2, HO-1, and NQO1.

RESULTS

BYHWD significantly enhanced neural function, reduced neuronal damage, inhibited the production of ROS, decreased MDA and 8-OHdG levels, increased SOD and GSH-PX activity to reduce oxidative damage, and restored mitochondrial membrane potential. BYHWD and Nrf2 activator TBHQ increased total Nrf2, nucleus Nrf2 protein expression, and its downstream HO-1 and NQO1 proteins, and the administration of the Nrf2 inhibitor brusatol reduced the enhancing effect of BYHWD. Meanwhile, BYHWD increased the expression of PKCε and P-PKCε and the administration of the PKCε inhibitor εV1-2 reduced the effect of BYHWD in increasing the expression of PKCε, P-PKCε, nuclear Nrf2, and HO-1, as well as promoting the effect of Nrf2 translocation to the nucleus.

CONCLUSION

This study marks the first to demonstrate that BYHWD ameliorates oxidative damage and attenuates brain I/R injury by activating the PKCε/Nrf2/HO-1 pathway.

The role of traditional herbal medicine for ischemic stroke: from bench to clinic-A critical review

BACKGROUND

Ischemic stroke (IS) is a leading cause of death and severe long-term disability worldwide. Over the past few decades, considerable progress has been made in anti-ischemic therapies. However, IS remains a tremendous challenge, with favourable clinical outcomes being generally difficult to achieve from candidate drugs in preclinical phase testing. Traditional herbal medicine (THM) has been used to treat stroke for over 2,000 years in China. In modern times, THM as an alternative and complementary therapy have been prescribed in other Asian countries and have gained increasing attention for their therapeutic effects. These millennia of clinical experience allow THM to be a promising avenue for improving clinical efficacy and accelerating drug discovery.

PURPOSE

To summarise the clinical evidence and potential mechanisms of THMs in IS.

METHODS

A comprehensive literature search was conducted in seven electronic databases, including PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, the Chinese National Knowledge Infrastructure, the VIP Information Database, the Chinese Biomedical Literature Database, and the Wanfang Database, from inception to 17 June 2022 to examine the efficacy and safety of THM for IS, and to investigate experimental studies regarding potential mechanisms.

RESULTS

THM is widely prescribed for IS alone or as adjuvant therapy. In clinical trials, THM is generally administered within 72 h of stroke onset and are continuously prescribed for over 3 months. Compared with Western medicine (WM), THM combined with routine WM can significantly improve neurological function defect scores, promote clinical total effective rate, and accelerate the recovery time of stroke with fewer adverse effects (AEs). These effects can be attributed to multiple mechanisms, mainly anti-inflammation, antioxidative stress, anti-apoptosis, brain blood barrier (BBB) modulation, inhibition of platelet activation and thrombus formation, and promotion of neurogenesis and angiogenesis.

CONCLUSIONS

THM may be a promising candidate for IS management to guide clinical applications and as a reference for drug development.

Combination of paeoniflorin and calycosin-7-glucoside alleviates ischaemic stroke injury via the PI3K/AKT signalling pathway

CONTEXT

Paeoniflorin (PF) and calycosin-7-glucoside (CG, Paeonia lactiflora Pall. extract) have demonstrated protective effects in ischaemic stroke.

OBJECTIVE

To investigate the synergistic effects of PF + CG on ischaemia/reperfusion injury in vivo and in vitro.

MATERIALS AND METHODS

Male Sprague-Dawley rats were subjected to the middle cerebral artery occlusion/reperfusion (MCAO/R). After MCAO/R for 24 h, rats were randomly subdivided into 5 groups: sham, model (MCAO/R), study treatment (PF + CG, 40 + 20 mg/kg), LY294002 (20 mg/kg), and study treatment + LY294002. Males were given via intragastric administration; the duration of the in vivo experiment was 8 days. Neurologic deficits, cerebral infarction, brain edoema, and protein levels were assessed in vivo. Hippocampal neurons (HT22) were refreshed with glucose-free DMEM and placed in an anaerobic chamber for 8 h. Subsequently, HT22 cells were reoxygenated in a 37 °C incubator with 5% CO₂ for 6 h. SOD, MDA, ROS, LDH and protein levels were measured in vitro.

RESULTS

PF + CG significantly reduced neurobehavioral outcomes (21%), cerebral infarct volume (44%), brain edoema (1.6%) compared with the MCAO/R group. Moreover, PF + CG increased p-PI3K/PI3K (4.69%, 7.4%), p-AKT/AKT (6.25%, 60.6%) and Bcl-2/BAX (33%, 49%) expression in vivo and in vitro, and reduced GSK-3β (10.5%, 9.6%) expression. In vitro, PF + CG suppressed apoptosis in HT22 cells and decreased ROS and MDA levels (20%, 50%, respectively).

CONCLUSIONS

PF + CG showed a synergistic protective effect against ischaemic brain injury, potentially being a future treatment for ischaemic stroke.

Understanding the multi-herbal composition of Buyang Huanwu Decoction: A review for better clinical use

ETHNOPHARMACOLOGICAL RELEVANCE

Buyang Huanwu Decoction (BHD) is a multi-herbal composition commonly prescribed in the treatment of cerebrovascular diseases such as stroke. Although studies have been conducted at the cellular (in vitro), animal and human (in vivo) level, there was no detailed analysis on how the composition and proportion of BHD is modified according to target diseases.

AIM OF STUDY

The purpose of this study is to investigate the composition and proportion of each herb in BHD to summarize how the original BHD was modified according to the target disease.

MATERIALS AND METHODS

Electronic literature searches were performed in three databases, collecting sixty-eight studies for the final analysis. The studies were divided into three types: cell studies, animal experiments and clinical trial. In the analysis, the decoction formula including the composition and the weight proportion of the herbs in BHD used in the studies and the target diseases were examined.

RESULTS

The result showed that in cell studies, the targets were mostly cell differentiation, cell injury and immune activation. In animal studies, cerebrovascular diseases such as cerebral ischemia were the most identified target diseases followed by nervous system and cardiovascular diseases. While the proportions of the herbs in BHD used in these studies were in general similar to the original formula, some studies reduced the amount of Astragali Radix to half of the original amount. Modified BHDs were used in four studies for cerebrovascular and peripheral nerve diseases. However, no significant correlation has been observed between the target diseases and the change of the proportion of the herbs in BHD.

CONCLUSIONS

The most commonly used formula was the original composition of BHD, and modified BHDs were reported to be used to treat cerebrovascular and nervous diseases. Further studies about the effects of BHD by composition and proportion of herbs are needed in the future.

Erythrocyte membrane affinity chromatography, solid-phase extraction and UPLC-QTOF-MS/MS to screen active ingredients of Buyang Huanwu decoction

Buyang Huanwu decoction (BHD) is a well-known traditional Chinese medicine that has long been used to treat ischemic brain damage which is associated with hemorheology. To screen active ingredients in BHD responsible for reducing blood viscosity by reducing red blood cell (RBC) lesions to treat ischemic stroke, a method involving RBC membrane binding and solid-phase extraction (SPE) was developed in this study. The components of BHD interacting with RBC were analyzed by mass spectrometry and four compounds, calycosin, paeoniflorin, 6-hydroxy behenol-3,6-di-O-glucoside and calycosin-7-O-β-d-glucoside, showed binding affinity to RBCs. An erythrocyte activity assay revealed that the identified ingredients promoted the activities of Na+-K+-ATPase, sialic acid and superoxide dismutase and reduced the content of cholesterol on the RBC membrane, suggesting a mechanism underlying their anti-erythrocyte aggregation activity. Based on these results, the RBC membrane binding assay combined with SPE and mass spectrometry is a novel and effective approach for screening potentially anti-erythrocyte lesion constituents in traditional Chinese medicines.

Temporal effect of acupuncture on amino acid neurotransmitters in rats with acute cerebral ischaemia

BACKGROUND

Acupuncture stimulation at GV26 during the acute phase of cerebral ischaemia can effectively reduce brain damage induced by ischaemic injury. However, the time course of the effects of acupuncture stimulation has not yet been thoroughly studied.

OBJECTIVE

To investigate the effects of manual acupuncture (MA) on glutamic acid (Glu) and γ-aminobutyric acid (GABA) expression in the cerebrospinal fluid of rats with middle cerebral artery occlusion (MCAO) and determine whether there is a temporal effect of acupuncture on the treatment of cerebral ischaemia.

METHODS

We performed thread occlusion of the right middle cerebral artery in rats to establish an animal model of MCAO. Simultaneously, during acupuncture treatment, microdialysis was used to continuously and dynamically observe immediate alterations in amino acid metabolism with acupuncture stimulation after cerebral ischaemia in vivo in this rat model of MCAO.

RESULTS

We found that, in comparison with an untreated MCAO group, Glu content was significantly decreased during the first acupuncture stimulation and during the course of the acupuncture treatment in the MCAO+MA group (MCAO vs MCAO+MA: day 1, P=0.032; day 2, P=0.021; day 3, P=0.017). These findings were also seen after the end of treatment when acupuncture was no longer applied (MCAO vs MCAO+MA: day 7, P=0.009). Measurements of GABA content following cerebral ischaemic injury showed that GABA peaks 24 hours after damage, falls thereafter and decreases to baseline levels on day 7. In the MCAO+MA group, GABA content on days 1 to day 2 was lower than in the MCAO group (MCAO+MA vs MCAO: day 1, P=0.003; day 2, P=0.001), although it was higher than in the control group (MCAO+MA vs control: day 1, P=0.024; day 2, P=0.009). GABA content on day 3 and day 7 was higher in the MCAO+MA group than in the MCAO group and the control group (MCAO+MA vs MCAO: day 3, P=0.008; day 7, P=0.013; MCAO+MA vs control: day 3, P=0.002; day 7, P=0.009).

CONCLUSION

Acupuncture stimulation at GV26 can effectively decrease excessive release of Glu induced by ischaemia and maintain the endogenous inhibitory activity of GABA. This phenomenon was seen during the entire course of acupuncture treatment and continued for some time after the end of acupuncture treatment.

A reliable LC-MS/MS method for the quantification of natural amino acids in mouse plasma: Method validation and application to a study on amino acid dynamics during hepatocellular carcinoma progression

A simple and fast LC-MS/MS method was developed and validated for simultaneous quantification of 20 proteinogenic l-amino acids (AAs) in a small volume (5 μL) of mouse plasma. Chromatographic separation was achieved on an Intrada Amino Acid column within 13 min via gradient elution with an aqueous solution containing 100 mM ammonium formate and an organic mobile phase containing acetonitrile, water and formic acid (v:v:v = 95:5:0.3), at the flow rate of 0.6 mL/min. Individual AAs and corresponding stable-isotope-labeled AAs internal standards were analyzed by multiple reaction monitoring (MRM) in positive ion mode under optimized conditions. Method validation consisted of linearity, sensitivity, accuracy and precision, recovery, matrix effect, and stability, and the results demonstrated this LC-MS/MS method as a specific, accurate, and reliable assay. This LC-MS/MS method was thus utilized to compare the dynamics of individual plasma AAs between healthy and orthotopic hepatocellular carcinoma (HCC) xenograft mice housed under identical conditions. Our results revealed that, 5 weeks after HCC tumor progression, plasma l-arginine concentrations were significantly decreased in HCC mice while l-alanine and l-threonine levels were sharply increased. These findings support the utilities of this LC-MS/MS method and the promise of specific AAs as possible biomarkers for HCC.

A Metabonomics Investigation into the Therapeutic Effects of BuChang NaoXinTong Capsules on Reversing the Amino Acid-Protein Interaction Network of Cerebral Ischemia

Background

Amino acids (AAs) in cerebrospinal fluid (CSF) play a pivotal role in cerebral ischemia (CI). BuChang NaoXinTong Capsules (BNC) are widely prescribed in Chinese medicine for the treatment of cerebrovascular and cardiovascular diseases.

Methods

In order to investigate the therapeutic effects and pharmacological mechanisms of BNC on reversing CI from a system level, an amino acid-protein interaction imbalanced network of CI containing metabolites of AAs, key regulatory enzymes, and proteins was constructed for the first time. Furthermore, a novel method for detecting the ten AAs in CSF was developed by UPLC-QQQ-MS in an effort to validate the imbalanced networks and the therapeutic effects of BNC via analysis of metabolites.

Results

Based on a middle cerebral artery occlusion (MCAO) rat model, the dynamic levels of amino acids in CSF 3, 6, 12, and 24 h after MCAO were analyzed. Up to 24 h, the accumulated nine AA biomarkers were found to significantly change in the MCAO group compared to the sham group and exhibited an obvious tendency for returning to baseline values after BNC treatment. In addition, based on the imbalanced network of CI, four key enzymes that regulate the generation of BNC-mediated AA biomarkers were selected and validated using an enzyme-linked immunosorbent assay and western blotting. Finally, aromatic-L-amino-acid decarboxylase (AADC) was found to be one of the putative targets for BNC-mediated protection against CI.

Conclusion

This study provides new strategies to explore the mechanism of cerebral ischemia and help discover the potential mechanism of BNC.

The effects of Bu Yang Huan Wu Tang on post-stroke epilepsy: a nationwide matched study

OBJECTIVE

To compare the long-term risk of epilepsy in stroke patients who use Bu Yang Huan Wu Tang (BYHWT) and those who do not.

METHODS

In the Taiwanese national insurance claims data, we identified newly diagnosed stroke patients receiving inpatient care in the years 2000-2004. Using propensity score-matched pairs to balance the baseline characteristics, we selected eligible stroke patients who did (n=8,971) and did not (n=8,971) receive BYHWT. These two groups were followed up until the end of 2009 to track the occurrence of epilepsy. We used Cox proportional hazard models to calculate the adjusted HRs and 95% CIs for post-stroke epilepsy during the follow-up period according to BYHWT use.

RESULTS

Compared with the control group, stroke patients with BYHWT had a reduced risk of epilepsy during the 5-9 years of the follow-up period (HR 0.69, 95% CI 0.61-0.77). The association between BYHWT and reduced post-stroke epilepsy was significant in various subgroups of stroke patients. There was a dose-dependent decrease in the frequency of epilepsy with increasing quantities of BYHWT use from 1 package (HR 0.77, 95% CI 0.66-0.90) to ≥6 packages (HR 0.52, 95% CI 0.42-0.65).

CONCLUSION

Stroke patients who received BYHWT therapy had a reduced long-term risk of epilepsy, and the beneficial effect could be observed in various subgroups. However, future clinical trials will be necessary to corroborate the present findings and identify the biochemical mechanism involved.

iTRAQ-Based Proteomics Analysis Reveals the Effect of Rhubarb in Rats with Ischemic Stroke

Background. Rhubarb, a traditional Chinese medicine, promotes viscera and remove blood stasis. Rhubarb is skilled in smoothening meridians, improving blood circulation which exhibits better efficacy on cerebral ischemic stroke. In this study, we aimed to analyze the underlying mechanisms of rhubarb which treated rats of middle cerebral artery occlusion (MCAO) model according to an iTRAQ-based proteomics and bioinformatics analysis. 30 rats were randomly allocated into three groups including sham group (SG), model group (MG), and rhubarb group (RG). Rhubarb group was given a gavage of rhubarb decoction at dose of 3 g/kg and the remaining groups were prepared with normal saline by gavage. Rats from MG and RG were induced into MCAO model. The effects of rhubarb were estimated by Modified Neurological Severity Score (mNSS) and cerebral infarct volume. The brain tissues were measured via the quantitative proteomic approach of iTRAQ coupled to liquid chromatography-tandem mass spectrometry (LC-MS/MS). Furthermore, the bioinformatics analysis of overlapping differentially expression proteins (DEPs) was conducted by DAVID, KEGG, and Cytoscape. Specific selective DEPs were validated by Western blotting. Rats treated with rhubarb after MCAO showed a significant reduction on mNSS and cerebral infarct volume compared with MG. In MG versus SG and RG versus MG, we identified a total of 4578 proteins, of which 287 were DEPs. There were 76 overlapping DEPs between MG versus SG and RG versus MG. Through bioinformatics analysis, 14 associated pathways were searched including cGMP-PKG signaling pathway, tuberculosis, synaptic vesicle cycle, amyotrophic lateral sclerosis, long-term potentiation, and so on. 76 overlapping DEPs mainly involved synaptic vesicle cycling biological processes based on GO annotation. Further, the selective overlapping DEPs were verified at the protein level by using Western blotting. Our present study reveals that rhubarb highlights promising neuroprotective effect. Rhubarb exerts novel therapeutic action via modulating multiple proteins, targets, and pathways.

Identification of active ingredients mediating anti-platelet aggregation effects of BuyangHuanwu decoction using a platelet binding assay, solid phase extraction, and HPLC-MS/MS

BuyangHuanwu decoction (BHD) is widely used as a traditional herbal medicine because of its antithrombotic effect, which is attributed to the inhibition of platelet aggregation; however, its active compounds remain unknown. In this study, we developed a method involving platelet binding, solid-phase extraction, and HPLC-MS/MS for screening BHD compounds with potential anti-platelet aggregation properties. Five compounds showing platelet binding affinity were identified as 6-hydroxykaempferol-di-O-glucoside, paeoniflorin, calycosin-7-O-β-d-glucoside, galloylpaeoniflorin, and formononetin-7-O-β-d-glucoside. The results of anti-platelet aggregation experiments in vitro confirmed that these compounds inhibited adenosine diphosphate-induced platelet aggregation. Our results suggest that a platelet binding assay combined with solid-phase extraction and HPLC-MS/MS is an effective method for screening anti-platelet aggregation agents in traditional Chinese medicines.

Facilitating effects of Buyang Huanwu decoction on axonal regeneration after peripheral nerve transection

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional Asian medicine, Buyang Huanwu decoction (BYHWD) has been used for the treatment of cardiovascular and neurological disorders. Recent experimental studies have begun to provide evidence on the protective effects of BYHWD on injured peripheral nerves.

AIM OF THE STUDY

To examine whether BYHWD was effective in inducing axonal regeneration after peripheral nerve transection, and if so, how it acted on the nerve.

MATERIALS AND METHODS

The sciatic nerve in rats was transected and resutured 0, 1, or 4 weeks later. BYHWD was orally administered daily into the animals with nerve transection and coaptation (NTC). Axonal regeneration was measured by immunofluorescence staining of NF-200 and superior cervical ganglion 10 (SCG10) and by retrograde tracing method. Changes of protein levels in the sciatic nerve were analyzed by western blot analysis. Effects of BYHWD and its constituents on neurite outgrowth were analyzed in cultured dorsal root ganglion (DRG) neurons. Hot plate and treadmill training tests were performed to assess the levels of functional recovery after nerve injury.

RESULTS

The rate of axonal regeneration was attenuated by delayed coaptation after transection, but improved by BYHWD treatment. Levels of phospho-Erk1/2 and Cdc2 phosphorylation of vimentin, measured as indicators of the activation of regenerating axons and supportive Schwann cells, were increased in the sciatic nerve of NTC animals, and their distribution in the proximal and distal nerves were affected by BYHWD treatment. Treatment of BYHWD during the period of chronic denervation significantly increased axonal regeneration when analyzed by immunofluorescence staining and retrograde tracing methods. Neurite outgrowth of DRG neurons cocultured with Schwann cells from the chronically transected sciatic nerves was enhanced by BYHWD treatment. Radix Paeoniae Rubra induced neurite outgrowth most efficiently among all herbal constituents of BYHWD. Finally, hot plate and treadmill training tests demonstrated that BYHWD administration significantly improved the sensorimotor nerve function in NTC animals.

CONCLUSIONS

Our data suggest that BYHWD treatment may contribute to the timely interaction between regenerating axons and distal Schwann cells in the transected nerve and facilitate axonal regeneration.

Recent trends in analytical methods for the determination of amino acids in biological samples

Amino acids are widely distributed in biological fluids and involved in many biological processes, such as the synthesis of proteins, fatty acids, and ketone bodies. The altered levels of amino acids in biological fluids have been found to be closely related to several diseases, such as type 2 diabetes, kidney disease, liver disease, and cancer. Therefore, the development of analytical methods to measure amino acid concentrations in biological samples can contribute to research on the physiological actions of amino acids and the prediction, diagnosis and understanding of diseases. This review describes the analytical methods reported in 2012-2016 that utilized liquid chromatography and capillary electrophoresis coupled with ultraviolet, fluorescence, mass spectrometry, and electrochemical detection. Additionally, the relationship between amino acid concentrations and several diseases is also summarized.

Upregulation of glutamate metabolism by BYHWD in cultured astrocytes following oxygen-glucose deprivation/reoxygenation in part depends on the activation of p38 MAPK

Recent studies have demonstrated that Buyang Huanwu Decoction (BYHWD) decreased glutamate levels subsequent to cerebral ischemia. Glutamate transporter-1 (GLT-1) and glutamine synthetase (GS), which are located in astrocytes, mainly contribute to glutamate transportation, thus reducing glutamate concentration. BYHWD has previously been demonstrated to upregulate GLT-1 and GS following ischemia in vivo. However, whether BYHWD can directly influence astrocytic GLT-1/GS levels remains unknown. In the present study, the effect of BYHWD containing serum (BYHWD-CS) on GLT-1/GS levels in astrocytes following oxygen-glucose deprivation/reoxygenation (OGD/R) was investigated. The results revealed that BYHWD-CS enhanced the expression levels of GLT-1 and GS in cultured astrocytes, which reduced glutamate concentration in the culture medium. Meanwhile, increased p38 mitogen-activated protein kinase (p38 MAPK) was phosphorylated (activation form) by BYHWD-CS in cultured astrocytes, and the specific p38 inhibitor SB203580 blocked the increase of GLT-1/GS accompanied by decreased cell viability. Furthermore, SB203580 suppressed the effect of BYHWD-CS on the level of glial fibrillary acidic protein (an astrocytic marker), thus confirming that astrocytes are directly involved in the protective role of BYHWD after OGD/R. These findings suggest that BYHWD upregulates GLT-1 and GS via p38 MAPK activation, and protects cultured astrocytes from death caused by OGD/R (typical in vitro model), which complemented the role of astrocytes in the protective effect of BYHWD.

Buyang Huanwu decoction facilitates neurorehabilitation through an improvement of synaptic plasticity in cerebral ischemic rats

BACKGROUND

Loss of neural function is a critical but unsolved issue after cerebral ischemia insult. Neuronal plasticity and remodeling are crucial for recovery of neural functions after brain injury. Buyang Huanwu decoction, which is a classic formula in traditional Chinese medicine, can positively alter synaptic plasticity. This study assessed the effects of Buyang Huanwu decoction in combination with physical exercise on neuronal plasticity in cerebral ischemic rats.

METHODS

Cerebral ischemic rats were administered Buyang Huanwu decoction and participated in physical exercise after the induction of a permanent middle cerebral artery occlusion. The neurobehavioral functions and infarct volumes were evaluated. The presynaptic (SYN), postsynaptic (GAP-43) and cytoskeletal (MAP-2) proteins in the coronal brain samples were evaluated by immunohistochemistry and western blot analyses. The ultrastructure of the neuronal synaptic junctions in the same region were analyzed using transmission electron microscopy.

RESULTS

Combination treatment of Buyang Huanwu decoction and physical exercise ameliorated the neurobehavioral deficits (p < 0.05), significantly enhanced the expression levels of SYN, GAP-43 and MAP-2 (p < 0.05), and maintained the synaptic ultrastructure.

CONCLUSIONS

Buyang Huanwu decoction facilitated neurorehabilitation following a cerebral ischemia insult through an improvement in synaptic plasticity. Graphical abstract The Buyang Huanwu decoction (BYHWD) combined with physical exercise (PE) attenuates synaptic disruption and promotes synaptic plasticity following cerebral ischemia (stroke).

Enhanced axonal regeneration of the injured sciatic nerve by administration of Buyang Huanwu decoction

ETHNOPHARMACOLOGICAL RELEVANCE

Buyang Huanwu decoction (BYHWD) has been used in the traditional Chinese medicine for the treatment of cardiovascular and neurological symptoms, and recent experimental studies have begun to provide evidence showing its protective effects on neural cells. Yet, its function for the regenerative responses of axons in the peripheral nerve after injury is not known.

AIM OF THE STUDY

The primary objective of the present study was to explore that BYHWD is involved in growth-promoting activity of the peripheral nerve axons after injury. We further examined whether the effect of BYHWD exerted directly on regrowing axons or Schwann cells.

MATERIALS AND METHODS

Sciatic nerves in rats were given crush injury, and BYHWD was injected by oral administration. Sciatic nerves or DRG tissues were prepared for immunofluorescence staining and western blot analysis. Levels of axonal regeneration were quantified by retrograde tracing technique. Cultured DRG sensory neurons and Schwann cells were prepared from rats and used to examine the effects of BYHWD on the neurite outgrowth. Behavioral analysis on functional recovery after nerve injury was assessed in mice by pin prick test, adhesive removal test, and toe-spreading reflex.

RESULTS

Immunofluorescence and retrograde tracing analyses showed that the distal extension of the sciatic nerve axons was significantly improved by BYHWD treatment. Levels of axonal growth-associated protein GAP-43 were upregulated by BYHWD treatment in the sciatic nerve after injury and in the neurites of cultured DRG neurons. In vivo administration of BYHWD in rats upregulated the induction level of cell division cycle 2 (Cdc2) and its phosphorylation of vimentin in Schwann cells from injured sciatic nerve. Coculture of DRG neurons with Schwann cells prepared from preinjured sciatic nerves in animals administered with BYHWD led to the enhancement in neurite outgrowth. Behavioral tests in mice given sciatic nerve injury showed a significant improvement in sensorimotor activity by BYHWD administration.

CONCLUSIONS

Our results suggest that BYHWD administration into animals given sciatic nerve injury facilitates axonal regeneration by acting on both the axons undergoing regeneration and neighboring Schwann cells and improves functional recovery.

Buyang Huanwu decoction increases the expression of glutamate transporter-1 and glutamate synthetase in association with PACAP-38 following focal ischemia

The neuroprotective role of Buyang Huanwu decoction (BYHWD) in focal ischemia is associated with decreasing glutamate concentration. However, the mechanisms are not fully understood. The present study aimed to explore whether glutamate transporter-1 (GLT-1) and glutamine synthetase (GS) participated in the decreased level of glutamate and whether pituitary adenylate cyclase-activating polypeptide-38 (PACAP-38) was involved in this process. BYHWD was found to significantly upregulate the expression of GLT-1 and GS in the hippocampal CA1 area compared to the ischemia group, with the difference on day 3 being most significant. BYHWD increased the level of PACAP-38, and PACAP-(6-38) (PACAP receptor antagonist) significantly attenuated the effect of BYHWD on GLT-1 and GS, suggesting that PACAP-38 was involved in the upregulation of GLT-1 and GS induced by BYHWD. In addition, as GLT-1 and GS are mainly located in astrocytes, the changes of astrocytes were detected by glial fibrillary acidic protein (GFAP; an astrocytic marker) immunostaining. The results showed that BYHWD inhibited the expression of GFAP compared with the ischemia group, however, co-administration with PACAP-(6-38), which inhibited the effect of BYHWD on GLT-1 and GS in astrocytes, attenuated this effect, indicating that astrocytes participated in the protective role of BYHWD following focal ischemia. These results provided the evidence for the first time that not only neurons but also astrocytes contribute to the protective role of BYHWD, which opposes previous studies and may be a starting point for traditional medicine.

A Systems Biology Perspective on the Molecular Mechanisms Underlying the Therapeutic Effects of Buyang Huanwu Decoction on Ischemic Stroke

Ischemic stroke is the leading cause of adult disability worldwide. The outcome is worse in older patients, especially in terms of disability. Buyang Huanwu decoction (BHD), a famous traditional Chinese medicine formula, has been used extensively in the treatment of ischemic stroke for centuries. However, its pharmacological mechanisms have not been fully elucidated. In this study, 82 putative targets for 411 composite compounds contained in BHD were predicted on the basis of our previously developed target prediction system. On the basis of large-scale molecular docking, more than 80% compound-putative target pairs had medium to strong binding efficiency. The pharmacological networks of BHD were built according to relationships among herbs, putative targets, and known therapeutic targets for ischemic stroke, and 121 major nodes were identified by calculating three topological features-degree, node betweenness, and closeness. Importantly, the pathway enrichment analysis identified several signaling pathways involved with major putative targets of BHD, such as the calcium signaling pathway, vascular smooth muscle contraction, and nucleotide-binding oligomerization domain (NOD)-like receptor signaling pathway, which have not hitherto been reported. These data are expected to help find new therapeutic effects of BHD and optimize clinical use of this formula. Collectively, our study developed a comprehensive systems approach integrating drug target prediction and network and functional analyses to reveal the relationships of the herbs in BHD with their putative targets, and for the first time with ischemic stroke-related pathway systems. This is a pilot study based on bioinformatics analysis; thus, further experimental studies are required to validate our findings.

PRRT2 Mutant Leads to Dysfunction of Glutamate Signaling

Paroxysmal kinesigenic choreoathetosis (PKC) is an inherited disease of the nervous system. We previously identified PRRT2 as the causative gene of PKC. However, as little is known about the function of PRRT2, elucidating its function will benefit not only PKC studies, but also many other related disorders. Here, we reveal higher levels of glutamate in the plasma of PKC patients and the culture medium of neurons following knock-out Prrt2 expression. Using double immunostaining assays we confirm Prrt2 is located at the glutamatergic neurons in accordance with its function. Our co-immunoprecipitation assays reveal mutant PRRT2 interferes with SNAP25 and GRIA1 interactions, respectively. Furthermore, using live-labeling techniques, we confirmed co-transfection with mutant PRRT2 caused an increase in GRIA1 distribution on the cell surface. Therefore, our results suggest that mutant PRRT2, probably through its weakened interaction with SNAP25, affects glutamate signaling and glutamate receptor activity, resulting in the increase of glutamate release and subsequent neuronal hyperexcitability.

Ameliorating effects of traditional Chinese medicine preparation, Chinese materia medica and active compounds on ischemia/reperfusion-induced cerebral microcirculatory disturbances and neuron damage

Ischemic stroke and ischemia/reperfusion (I/R) injury induced by thrombolytic therapy are conditions with high mortality and serious long-term physical and cognitive disabilities. They have a major impact on global public health. These disorders are associated with multiple insults to the cerebral microcirculation, including reactive oxygen species (ROS) overproduction, leukocyte adhesion and infiltration, brain blood barrier (BBB) disruption, and capillary hypoperfusion, ultimately resulting in tissue edema, hemorrhage, brain injury and delayed neuron damage. Traditional Chinese medicine (TCM) has been used in China, Korea, Japan and other Asian countries for treatment of a wide range of diseases. In China, the usage of compound TCM preparation to treat cerebrovascular diseases dates back to the Han Dynasty. Even thousands of years earlier, the medical formulary recorded many classical prescriptions for treating cerebral I/R-related diseases. This review summarizes current information and underlying mechanisms regarding the ameliorating effects of compound TCM preparation, Chinese materia medica, and active components on I/R-induced cerebral microcirculatory disturbances, brain injury and neuron damage.

Montelukast, a cysteinyl leukotriene receptor-1 antagonist protects against hippocampal injury induced by transient global cerebral ischemia and reperfusion in rats

Cysteinyl leukotrienes (CysLTs) are potent pro-inflammatory and immune modulating lipid mediators involved in inflammatory diseases and were boosted in human brain after acute phase of cerebral ischemia. The antagonism of CysLTs receptors may offer protection against ischemic damage. Therefore it seemed interesting to study the possible neuroprotective effect of Montelukast, a CysLTR1 antagonist in global cerebral ischemia/reperfusion (IR) injury in rats. Global cerebral ischemia-reperfusion was induced by bilateral carotid artery occlusion for 15 min followed by 60 min reperfusion period. Animals were randomly allocated into three groups (n = 30 per group): Sham operated, I/R control and rats treated with montelukast (0.5 mg/kg, po) daily for 7 days then I/R was induced 1 h after the last dose of montelukast. After reperfusion rats were killed by decapitation, brains were removed and both hippocampi separated and the following biochemical parameters were estimated; lactate dehydrogenase activity, oxidative stress markers (lipid peroxides, nitric oxide and reduced glutathione), inflammatory markers (myeloperoxidase, tumor necrosis factor-alpha, nuclear factor kappa-B, interleukin-6 and interleukin-10), apoptotic biomarkers (caspase 3 and cytochrome C), neurotransmitters (glutamate, gamma aminobutyric acid), Cys-LTs contents and CysLT1 receptor expression; as well as total brain infarct size and histopathological examination of the hippocampus were assessed. Montelukast protected hippocampal tissue by reducing oxidative stress, inflammatory and apoptotic markers. Furthermore, it reduced glutamate and lactate dehydrogenase activity as well as infarct size elevated by I/R. These results were consistent with the histopathological findings. Montelukast showed a neuroprotective effects through antioxidant, anti-inflammatory and antiapoptotic mechanisms.

Neuroprotective effects of Buyang Huanwu decoction on cerebral ischemia-induced neuronal damage

Among the various treatment methods for stroke, increasing attention has been paid to traditional Chinese medicines. Buyang Huanwu decoction is a commonly used traditional Chinese medicine for the treatment of stroke. This paper summarizes the active components of the Chinese herb, which is composed of Huangqi (Radix Astragali seu Hedysari), Danggui (Radix Angelica sinensis), Chishao (Radix Paeoniae Rubra), Chuanxiong (Rhizoma Ligustici Chuanxiong), Honghua (Flos Carthami), Taoren (Semen Persicae) and Dilong (Pheretima), and identifies the therapeutic targets and underlying mechanisms that contribute to the neuroprotective properties of Buyang Huanwu decoction.