Unveiling allelopathic dynamics and impacts of invasive Erigeron bonariensis and Bidens pilosa on plant communities and soil parameters

Invasive alien species are becoming more and more prevalent worldwide, Erigeron bonariensis and Bidens pilosa are two invasive species of Asteraceae in Egypt. To mitigate their detrimental effects and understand their differences in invasiveness, we compared the allelopathic potentials of E. bonariensis and B. pilosa using leachates, decaying residues, and volatilization processes. Notably, the allelopathic variances in leachates were significant, influenced by plant types, concentrations, and response patterns of target plant traits, as indicated by EC50. The relative phytotoxicity of the invasive species decayed residues peaked between 20 and 25 days in the soil, with a positive correlation with concentrations and soil properties. The highest quantities of phenolic acids were chlorogenic acid and caffeic acid reaching (5.41 and 4.39 µg g-1) E. bonariensis and (4.53 and 4.46 µg g-1) B. pilosa, in leachates extracts respectively, while in the soil extract of decayed residues were coumaric acid and ferulic acid measuring (1.66 and 1.67 µg g-1) E. bonariensis and (1.47 and 1.57 µg g-1) B. pilosa, respectively. Using GC/MS analysis, the main volatile components in E. bonariensis were 1, 8 cineole (5.62%), and α-terpinene (5.43%) and iso-Caryophyllene (5.2%) which showed the greatest inhibitory effects. While B. pilosa main constituents were trans-sabinene (5.39%) and Camphene (5.11%), respectively. Finally, the high invasion level displayed from E. bonariensis (0.221) compared with B. pilosa (0.094) which correlated with the stronger allelopathic activities against plant species, and soil properties. Therefore, the allelopathic potentialities of these species are critically relevant to their invasion success.

Caffeoylquinic acids protect against alcoholic liver injury and rare C10 acetylenic acids from Erigeron breviscapus

Three new compounds (1-2, 4) along with ten known ones (3, 5-13), were isolated from the whole plant of Erigeron breviscapus. Compounds 1 and 2, two novel C10 acetylenic acids and compound 4, a jasmone glucoside were elucidated by the detailed analysis of 1D and 2D NMR, HRESIMS spectra, and experimental and calculated electronic circular dichroism (ECD). Compounds 1-3 represent the first example of acetylenic acids incorporating C10 skeleton from E. breviscapus. In addition, the antioxidant effects of all compounds were evaluated by ferric reducing power, 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate acid) (ABTS) and 2.2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. Our results indicated the significant antioxidant activity of caffeoylquinic acids. Additionally, compounds 10-11 and 13 played protective role on alcoholic liver injury cells in a dose-dependent manner.

Study on the anti-mitochondrial apoptosis mechanism of Erigeron breviscapus injection based on UPLC-Q-TOF-MS metabolomics and molecular docking in rats with cerebral ischemia-reperfusion injury

ETHNOPHARMACOLOGICAL RELEVANCE

Erigeron breviscapus is a common medicine of eight ethnic minorities, including Miao, Naxi, and Yi. As early as the Ming Dynasty (AD 1368-1644), Lanmao's Materia Medica of Southern Yunnan (AD 1436) recorded that the medicine is used for the treatment of "Zuo tan you huan." In modern pharmacological research, Erigeron breviscapus injection is the most commonly used preparation in the treatment of ischemic stroke caused by acute cerebral infarction, but its mechanism of action in the treatment of ischemic stroke is not well understood.

AIM OF THE STUDY

In this study, a metabonomics study based on ultraperformance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS) was used in investigating the effect of a traditional Chinese medicine preparation Erigeron breviscapus injection on the rat model of focal cerebral ischemia-reperfusion and the affinity of its main components with the targets of mitochondrial apoptotic pathways.

MATERIALS AND METHODS

This study used molecular docking technology to verify the effective binding ability of main effective components of Erigeron breviscapus injection to target proteins related to mitochondrial apoptosis pathway. This study developed a metabonomics method based on the ultra-performance liquid chromatography combined with quadrupole time-of-flight tandem mass spectrometry (UPLC Q-TOF MS) to evaluate the efficacy and study the mechanism of traditional Chinese medicine preparation. With pattern recognition analysis (principal component analysis and partial least squares-discriminate analysis) of urinary metabolites, a clear separation of focal cerebral ischemia-reperfusion model group and healthy control group was achieved.

RESULTS

Erigeron breviscapus injection can significantly reduce the area of cerebral infarction, improve tissue morphological lesion in rats, and can increase the number of Nissl bodies. It may be a promoting factor by inhibiting hippocampal nerve cell apoptosis and Bax protein expression and by exerting effects against ischemia reperfusion after the induction of apoptosis. Thus, it plays a role in brain protection. Moreover, it can considerably promote the recovery of neurological deficiency signs in advance. Meanwhile, Erigeron breviscapus decreased malondialdehyde content and T-NOS activity. Its curative effect from strong to weak order: low dose > high dose > medium dose. The representative components of Erigeron breviscapus have good affinity with the active sites of mitochondrial apoptosis-related proteins. Metabolomics found that the potential biomarkers regulated by breviscapine are kynurequinolinic acid, succinylornithine, and leucine proline. It is speculated that it may participate in TRP-kynurequinolinic acid and succinylornithine-urea cycle-NO metabolic pathways.

CONCLUSIONS

This paper revealed the potential biomarkers and metabolic pathways regulated by Erigeron breviscapus. It was speculated that the mechanism is related to its inhibition of mitochondrion-mediated apoptosis. Erigeron breviscapus could restore the metabolic profiles of the model animals to normal animal levels. The mechanism may be related to the potential biomarkers of quinolinic acid, succinylornithine, and leucine proline and the metabolic pathways involved. However, the exact mechanism by which Erigeron breviscapus inhibits mitochondrion-mediated apoptosis remains to be further explored.

Dengzhan Xixin injection derived from a traditional Chinese herb Erigeron breviscapus ameliorates cerebral ischemia/reperfusion injury in rats via modulation of mitophagy and mitochondrial apoptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Dengzhan Xixin injection (DX), a preparation of extracts from traditional Chinese medicine Erigeron breviscapus (Vaniot) Hand.-Mazz., has been widely used in clinical treatment of cerebral ischemia sequelae in China for a long history. However, its underlying mechanisms remain unclear.

AIM OF THE STUDY

The objective of this present study aimed to investigate the therapeutic effects of DX on cerebral ischemia/reperfusion (I/R) injury in a rat model. Meanwhile, its underlying molecular mechanisms on mitochondrial protection were further interpreted.

MATERIALS AND METHODS

The major components of DX were detected by high-performance liquid chromatography analysis. The model of cerebral I/R injury was established by middle cerebral artery occlusion (MCAO) in SD rats. We firstly performed neurobehavioral score, the regional cerebral blood flow (rCBF) assay, and TTC, HE and Nissl staining for evaluating the effects of DX on I/R injury. And then, the cortical levels of reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), adenosine triphosphate (ATP) and mitochondrial membrane potential (MMP) were determined by commercial kits. Whereafter, real time-PCR and transmission electron microscopy were employed to investigate the relative copy number of mitochondrial DNA (mtDNA) and neuronal ultrastructure changes, respectively. Further, the potential interactions of major components in DX with mitophagy/apoptosis-related proteins were predicted by Schrodinger molecular docking. The expression of mitophagy-related proteins LC3, p62, TOM20, PINK1 and Parkin was estimated by western blot and immunofluorescence analyses. Furthermore, TUNEL staining and western blot were used to detect the apoptotic phenomenon and the protein expression of Bax, Bcl-2, Cytochrome c (Cyto-c) and cleaved Caspase-3.

RESULTS

DX mainly contains scutellarin, 3,4-O-dicaffeoylquinic acid, 3,5-O-dicaffeoylquinic acid, 4,5-O-dicaffeoylquinic acid, caffeic acid and 5-O-caffeoylquinic acid. Compared with the model group, DX could remarkably relieve ischemia-provoked neurological deficit, rCBF deficiency and cerebral infarction. Pathological changes and neuronal loss in a MCAO model of rats were memorably ameliorated by DX administration. Meanwhile, DX reduced the surged ROS and MDA, while increased the level of SOD. Notably, DX treatment conversed the collapse of ATP and MMP, along with decreased in the relative copy number of mtDNA, contributing to the maintaining of mitochondrial ultrastructure via the increased number of autophagy lysosomes. The representative ingredients in DX had a potential bind with the active sites of mitophagy/apoptosis-related proteins. DX stimulated the protein expression of LC3, PINK1 and Parkin, while reduced the levels of p62 and TOM20. In addition, DX confined TUNEL-positive cell rate with the decreased expressions of Bax, Cyto-c and cleaved Caspase-3 as well as the increased Bcl-2 level.

CONCLUSIONS

We demonstrated that the protection of DX against brain ischemia could attribute to alleviating mitochondrial damage by upregulating mitophagy and inhibiting mitochondria-mediated apoptosis.

Comparative genomics reveal the convergent evolution of CYP82D and CYP706X members related to flavone biosynthesis in Lamiaceae and Asteraceae

Distant species producing the same secondary metabolites is an interesting and common phenomenon in nature. A classic example of this is scutellarein whose derivatives have been used clinically for more than 30 years. Scutellarein occurs in significant amounts in species of two different orders, Scutellaria baicalensis and Erigeron breviscapus, which diverged more than 100 million years ago. Here, according to the genome-wide selection and functional identification of 39 CYP450 genes from various angiosperms, we confirmed that only seven Scutellaria-specific CYP82D genes and one Erigeron CYP706X gene could perform the catalytic activity of flavone 6-hydroxylase (F6H), suggesting that the convergent evolution of scutellarein production in these two distant species was caused by two independently evolved CYP450 families. We also identified seven Scutellaria-specific CYP82D genes encoding flavone 8-hydroxylase (F8H). The evolutionary patterns of CYP82 and CYP706 families via kingdom-wide comparative genomics highlighted the evolutionary diversity of CYP82D and the specificity of CYP706X in angiosperms. Multi-collinearity and phylogenetic analysis of CYP82D in Scutellaria confirmed that the function of F6H evolved from F8H. Furthermore, the SbaiCYP82D1^A319D , EbreCYP706X^R130A , EbreCYP706X^F312D and EbreCYP706X^A318D mutants can significantly decrease the catalytic activity of F6H, revealing the contribution of crucial F6H amino acids to the scutellarein biosynthesis of distant species. This study provides important insights into the multi-origin evolution of the same secondary metabolite biosynthesis in the plant kingdom.

Chemical characteristics and significant antitussive effect of the Erigeron canadensis polyphenolic polysaccharide-protein complex

ETHNOPHARMACOLOGICAL RELEVANCE

Erigeron canadensis has been used in traditional medicine to treat a variety of respiratory diseases, including acute upper and lower respiratory tract infections and cough-related asthma. There is as yet no relevant experimental or clinical study in the scientific literature evaluating the efficacy of plants in these disorders.

AIM OF THE STUDY

To investigate the active ingredients in Erigeron canadensis, a complex isolated from flowering parts of a plant was tested for airway defense reflexes, in particular for cough reflexes and airway reactivity. Both were experimentally induced by a chemical irritant that simulated the inflammatory conditions of their formation.

MATERIAL AND METHODS

The polyphenolic polysaccharide-protein (PPP) complex was isolated from the flowering parts of Erigeron canadensis by hot alkaline extraction and a multi-stage purification process. The antitussive activity was confirmed as a decrease in the number of citric acid-induced coughs and the bronchodilator effect was verified as a decrease in specific airway resistance (sRaw) in conscious guinea pigs.

RESULTS

The dark brown Erigeron complex with a molecular weight of 38,000 g/mol contained phenolics (13.2% wt%), proteins (16.3% wt%), and uronic acids (6.3% wt%). The neutral carbohydrate part of Erigeron consisted mainly of xylose (12.1 wt%), glucose (13.3 wt%), arabinose (24.1 wt%), and galactose (41.0 wt%) residues. Arabinogalactan and 4-OMe-glucuronoxylan have been found to be the major polysaccharides in the Erigeron complex. Using a method of chemically-induced cough reflex and guinea pigs test system the Erigeron complex exhibited statistically significant, the dose-dependent antitussive activity, which was similar to that of the centrally-acting opioid agonist codeine.

CONCLUSION

Pharmacological tests have revealed a new pharmacodynamic effect of the Erigeron complex, namely an antitussive effect. Its activity was most pronounced in comparison with all previously tested compounds from other medicinal plants and approached the effect of codeine, the most potent antitussive used in clinical practice. The results provide the scientific basis for the application of this herb in traditional medicine.

Protective mechanism of Erigeron breviscapus injection on blood-brain barrier injury induced by cerebral ischemia in rats

This study investigates the protective effect of Erigeron breviscapus injection, a classic traditional Chinese medicine most typically used by Chinese minority to treat stroke, on cerebral ischemia-reperfusion injury and the related signaling pathways. Use network pharmacology methods to study the relationship between E. breviscapus (Vant.) Hand-Mazz. and ischemic stroke, predict the mechanism and active ingredients of E. breviscapus (Vant.) Hand-Mazz. in improving ischemic stroke disease. We study the protective effect of E. breviscapus injection on blood-brain barrier (BBB) injuries induced by cerebral ischemia in rats by regulating the ROS/RNS-MMPs-TJs signaling pathway. The rat model of focal cerebral ischemia-reperfusion injury has been prepared using the wire-suppository method. Firstly, the efficacy of E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid in protecting BBB injury caused by cerebral ischemia has been evaluated. Secondly, the following two methods have been used to study the mechanism of E. breviscapus injection in regulating the ROS/RNS-MMPS-TJS signaling pathway: real-time PCR and western blot for the determination of iNOS, MMP-9, claudin-5, occludin, ZO-1 mRNA and protein expression in brain tissue. We find that PI3K-Akt signaling pathway predicted by network pharmaology affects the blood-brain barrier function, so we chose the blood-brain barrier-related MMP-9, claudin-5, iNOS, occludin and ZO-1 proteins are used for research. The results of our research show that 3 drugs can reduce the rate of cerebral infarction in rats, relieve the abnormal neuroethology of rats, reduce the degree of brain tissue lesion, increase the number of the Nissl corpuscle cells and repair the neuron ultrastructure in injured rats. At the same time, it can obviously reduce the ultrastructure damage of the BBB in rats. All three drugs significantly reduced the content of Evans blue in the ischemic brain tissue caused by cerebral ischemia in rats with BBB injury. In addition, E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid can decrease the protein expression of iNOS and MMP-9 in rat ischemic brain tissue. In addition, 3,5-dicaffeoylquinic acid can increase the protein expression of claudin-5. We conclude that E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid have obvious therapeutic effects on BBB and neuron injury induced by cerebral ischemia in rats. Our results from studying the mechanism of action show that E. breviscapus injection and Scutellarin inhibited the activation of MMP-9 by inhibiting the synthesis of iNOS, 3,5-dicaffeoylquinic acid inhibits the expression and activation of MMP-9 by inhibiting the activation of iNOS and reducing the generation of free radicals, thus reducing the degradation of important cytoskeleton connexin claudin-5 in the tight junction (TJ) structure by inhibiting the expression and activation of MMP-9. Finally BBB structure integrity was protected.

Identification and Characterization of Two New 1- O-Acyl-glucose-ester Forming Glucosyltransferases from Erigeron breviscapus

Two versatile UDP-glucosyltransferases, UGT75L25 and UGT75X1, were isolated from Erigeron breviscapus. The enzymes display high sequence identity to flavonoid 7- O-glucosyltransferase from Malus species and cluster to the phylogenetic group L of plant glucosyltransferases, also involved in the formation of hydroxycinnamoyl glucose esters, which are used as bifunctional donors in the glucosylation or acylation of anthocyanins. The enzymes, functionally expressed in Escherichia coli, exhibit broad substrate specificity toward 21 structurally diverse types of phenolic acids, including (hydroxy)cinnamates, vanillic acid, 3-hydroxycoumarin, and 7-hydroxyflavonoids. The catalytic characteristics of UGT75L25 and UGT75X1 were exploited to generate the corresponding acyl-glucose-esters or glucosides with high efficiency. These findings demonstrate the significant potential of acyl-glucose-esters in the further enzymatic synthesis of bioactive anthocyanins.

A UPLC-ESI-MS/MS Method for Simultaneous Quantitation of Chlorogenic Acid, Scutellarin, and Scutellarein in Rat Plasma: Application to a Comparative Pharmacokinetic Study in Sham-Operated and MCAO Rats after Oral Administration of Erigeron breviscapus Extract

Erigeron breviscapus, a traditional Chinese medicine, is clinically used for the treatment of occlusive cerebral vascular diseases. We developed a sensitive and reliable ultra-performance liquid chromatography-electrospray-tandem mass spectrometry (UPLC-ESI-MS/MS) method for simultaneous quantitation of chlorogenic acid, scutellarin, and scutellarein, the main active constituents in Erigeron breviscapus, and compared the pharmacokinetics of these active ingredients in sham-operated and middle cerebral artery occlusion (MCAO) rats orally administrated with Erigeron breviscapus extract. Plasma samples were collected at 15 time points after oral administration of the Erigeron breviscapus extract. The levels of chlorogenic acid, scutellarin, and scutellarein in rat plasma at various time points were determined by a UPLC-ESI-MS/MS method, and the drug concentration versus time plots were constructed to estimate pharmacokinetic parameters. The concentration of chlorogenic acid in the plasma reached the maximum plasma drug concentration in about 15 min and was below the limit of detection after 4 h. Scutellarin and scutellarein showed the phenomenon of multiple absorption peaks in sham-operated and MCAO rats, respectively. Compared with the sham-operated rats, the terminal elimination half-life of scutellarein in the MCAO rats was prolonged by more than two times and the area under the curve of each component in the MCAO rats was significantly increased. The results showed chlorogenic acid, scutellarin, and scutellarein in MCAO rats had higher drug exposure than that in sham-operated rats, which provided a reference for the development of innovative drugs, optimal dosing regimens, and clinical rational drug use.

Synthesis of Scutellarein Derivatives with a Long Aliphatic Chain and Their Biological Evaluation against Human Cancer Cells

Scutellarin is the major active flavonoid extracted from the traditional Chinese herbal medicine Erigeron breviscapus (Vant.) Hand-Mazz., which is widely used in China. Recently, accumulating evidence has highlighted the potential role of scutellarin and its main metabolite scutellarein in the treatment of cancer. To explore novel anticancer agents with high efficiency, a series of new scutellarein derivatives with a long aliphatic chain were synthesized, and the antiproliferative activities against Jurkat, HCT-116 and MDA-MB-231 cancer cell lines were assessed. Among them, compound 6a exhibited the strongest antiproliferative effects on Jurkat (IC₅₀ = 1.80 μM), HCT-116 (IC₅₀ = 11.50 μM) and MDA-MB-231 (IC₅₀ = 53.91 μM). In particular, 6a even showed stronger antiproliferative effects than the positive control NaAsO₂ on Jurkat and HCT-116 cell lines. The results showed that a proper long aliphatic chain enhanced the antiproliferative activity of scutellarein.

Scutellarin Ameliorates Learning and Memory Deficit via Suppressing β-Amyloid Formation and Microglial Activation in Rats with Chronic Cerebral Hypoperfusion

Chronic cerebral hypoperfusion is considered as a pivotal factor of cognitive impairment that occurs in cerebrovascular diseases. This study investigated the ameliorating effect of scutellarin (SCT) on spatial cognitive impairment and β-amyloid (Aβ) formation in rats with chronic cerebral hypoperfusion induced by permanent bilateral common carotid artery occlusion (pBCAO). SCT is a flavonoid in medicinal herb of Erigeron breviscapus (vant.) Hand. Mazz. known to have neuroprotective, antioxidative and anti-inflammatory effects. However, the beneficial effect and pivotal mechanism of SCT on cognitive impairment are still unclear. SCT was treated orally with two doses (10 or 30 mg/kg) for 4 weeks. Results of Morris water maze test performed on the ninth week after pBCAO revealed that SCT (30 mg/kg)-treated rats had significantly shortened escape latencies in acquisition training trials, significantly prolonged swimming time at the platform and its surrounding zone, significant increase in memory score, significant reduction in the number of target heading, and significant reduction in the time required for the first target heading during the retention trial compared to rats in the sham-control group. SCT significantly inhibited the production of Aβ(1-40) and Aβ(1–42) in brain tissues. However, SCT significantly upregulated the expression levels of amyloid precursor protein and β-site APP-converting enzyme-1 in the hippocampus. In addition, SCT significantly inhibited the activation of Iba1-expressing microglia in brain tissues. The results suggest that SCT can exert ameliorating effect on spatial cognitive impairment caused by chronic cerebral hypoperfusion through suppressing Aβ formation and microglial activation in brain tissues. Therefore, SCT can be used as a beneficial drug for vascular dementia and Alzheimer's disease.

Synthesis and Bioactivity Characterization of Scutellarein Sulfonated Derivative

Scutellarin (1) has been widely used to treat acute cerebral infarction in clinic, but poor aqueous solubility decreases its bioavailability. Interestingly, scutellarin (1) could be metabolized into scutellarein (2) in vivo. In this study, a sulfonic group was introduced at position C-8 of scutellarein (2) to enhance the aqueous solubility of the obtained derivative (3). DPPH (1,1-diphenyl-2-picrylhydrazyl)-radical scavenging ability and antithrombic activity were also conducted to determine its bioactivity. The result showed that scutellarein derivate (3) could be a better agent for ischemic cerebrovascular disease treatment.

Ultra-high Performance Liquid Chromatography with Photodiode Array and Chemiluminescence Detection for the Determination of Polyphenolic Antioxidants in Erigeron acris L. Extracts

INTRODUCTION

The quality of herbs is directly related to the presence of polyphenolic antioxidants. This is the first report on the quantification of individual polyphenolic constituents of Erigeron acris L.

OBJECTIVE

To develop a new method using ultra-high performance liquid chromatography with photodiode array and chemiluminescence (UHPLC-PDA-CL) detection for the separation and determination of polyphenols in Erigeron acris extracts.

METHODOLOGY

The methanolic extracts from leaves and inflorescences of Erigeron acris were prepared by ultrasound assisted extraction. The chromatographic separation was performed on C18 column packed with 1.7-μm particles. The post-column CL detection was based on the enhancing effect of polyphenols on the CL generated in manganese(IV)-hexametaphosphate-formaldehyde system.

RESULTS

The UHPLC method allowed to separate polyphenols in a short running time (13 min), which was three times shorter compared with traditional HPLC. The CL detection was characterised by 6-48 times higher sensitivity and up to three times lower detection limits compared to PDA detection. Qualitative and quantitative differences were observed in polyphenolic composition of Erigeron acris extracts. The main components of leaves were scutellarin and chlorogenic acid, whereas in inflorescences quercetin 3-O-glucoside was predominant.

CONCLUSION

Coupling of UHPLC with CL detection has been developed for the first time. This advanced chromatographic technique coupled with sensitive CL detection is a powerful approach for the investigation of polyphenolic profiles in natural products. The shorter analysis time and diminished waste generation makes the UHPLC method more environmentally friendly and more cost-effective in comparison with conventional HPLC. Copyright © 2016 John Wiley & Sons, Ltd.

Biological Activities of the Essential Oil from Erigeron floribundus

Erigeron floribundus (Asteraceae) is an herbaceous plant widely used in Cameroonian traditional medicine to treat various diseases of microbial and non-microbial origin. In the present study, we evaluated the in vitro biological activities displayed by the essential oil obtained from the aerial parts of E. floribundus, namely the antioxidant, antimicrobial and antiproliferative activities. Moreover, we investigated the inhibitory effects of E. floribundus essential oil on nicotinate mononucleotide adenylyltransferase (NadD), a promising new target for developing novel antibiotics, and Trypanosoma brucei, the protozoan parasite responsible for Human African trypanosomiasis. The essential oil composition was dominated by spathulenol (12.2%), caryophyllene oxide (12.4%) and limonene (8.8%). The E. floribundus oil showed a good activity against Staphylococcus aureus (inhibition zone diameter, IZD of 14 mm, minimum inhibitory concentration, MIC of 512 µg/mL). Interestingly, it inhibited the NadD enzyme from S. aureus (IC₅₀ of 98 µg/mL), with no effects on mammalian orthologue enzymes. In addition, T. brucei proliferation was inhibited with IC₅₀ values of 33.5 µg/mL with the essential oil and 5.6 µg/mL with the active component limonene. The essential oil exhibited strong cytotoxicity on HCT 116 colon carcinoma cells with an IC₅₀ value of 14.89 µg/mL, and remarkable ferric reducing antioxidant power (tocopherol-equivalent antioxidant capacity, TEAC = 411.9 μmol·TE/g).

Clinical tolerability and pharmacokinetics of Erigerontis hydroxybenzene injection: results of a randomized phase I study in healthy Chinese volunteers

Multiple phenolic compounds in the extract of Erigeron breviscapus synergistically contribute to the neurovascular protective effects. We conducted a phase I and pharmacokinetic study with the phenolic compound-enriched product extracted from Erigeron breviscapus, Erigerontis hydroxybenzenes injection (EHI), in healthy Chinese volunteers. A randomized, open-label, single-center, double-arm, dose-escalation study of EHI was conducted. The tolerability of intravenously EHI administrated in single- or multiple-dose (once daily for 7 days) was studied in 40 healthy Chinese volunteers and the pharmacokinetics of EHI was studied in additional 10 volunteers. The tolerated dose of intravenous infusion of EHI in healthy Chinese volunteers was 6 vials (equivalent to 90 mg bioactive phenolic compounds). The main limitations to dose escalation of EHI were transit changes in electrocardiogram and mild, transit increase in alanine aminotransferase. After intravenous administration of EHI, the average systemic clearance of multiple phenolic compounds of scutellarin, 1,3-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, and 3,4-dicaffeoylquinic acid were 131, 29, 262, 112 L/h for male volunteers and 202, 28, 252, 117 L/h for female volunteers. The intervention of intravenous infusion of EHI in healthy Chinese volunteers was generally tolerated. The findings from this study provide data on the tolerability and pharmacokinetics of the extract from Erigeron breviscapus and support further trials.

Phenolic constituents of Erigeron floribundus (Asteraceae), a Cameroonian medicinal plant

HPLC-MS analysis of extracts of the Cameroonian medicinal plant Erigeron floribundus (Kunth) Sch. Bip. (Asteraceae) led to the identification of 40 different phenolic constituents. Four triterpene derivatives were isolated using semi-preparative HPLC and structures were elucidated on the basis of 1D and 2D NMR measurements. Compound 1, olean-3-oleil-12,18 diene, was a new natural product. Quali-quantitative measurements on the infusion obtained from dried aerial parts were also performed by HPLC-MSn and HPLC-DAD analysis showing that a cup of E. floribundus tea contains about 2.7 mg/mL of phenolics, with the caffeoyl quinic derivatives being the most abundant constituents.

Therapeutic time window and underlying therapeutic mechanism of breviscapine injection against cerebral ischemia/reperfusion injury in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Breviscapine injection is a Chinese herbal medicine standardized product extracted from Erigeron breviscapus (Vant.) Hand.-Mazz. It has been widely used for treating cardiovascular and cerebrovascular diseases. However, the therapeutic time window and the action mechanism of breviscapine are still unclear. The present study was designed to investigate the therapeutic time window and underlying therapeutic mechanism of breviscapine injection against cerebral ischemic/reperfusion injury.

MATERIALS AND METHODS

Sprague-Dawley rats were subjected to middle cerebral artery occlusion for 2h followed by 24h of reperfusion. Experiment part 1 was used to investigate the therapeutic time window of breviscapine. Rats were injected intravenously with 50mg/kg breviscapine at different time-points of reperfusion. After 24h of reperfusion, neurologic score, infarct volume, brain water content and serum level of neuron specific enolase (NSE) were measured in a masked fashion. Part 2 was used to explore the therapeutic mechanism of breviscapine. 4-Hydroxy-2-nonenal (4-HNE), 8-hydroxyl-2'- deoxyguanosine (8-OHdG) and the antioxidant capacity of ischemia cortex were measured by ELISA and ferric-reducing antioxidant power (FRAP) assay, respectively. Immunofluorescence and western blot analysis were used to analyze the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1).

RESULTS

Part 1: breviscapine injection significantly ameliorated neurologic deficit, reduced infarct volume and water content, and suppressed the levels of NSE in a time-dependent manner. Part 2: breviscapine inhibited the increased levels of 4-HNE and 8-OHdG, and enhanced the antioxidant capacity of cortex tissue. Moreover, breviscapine obviously raised the expression of Nrf2 and HO-1 proteins after 24h of reperfusion.

CONCLUSION

The therapeutic time window of breviscapine injection for cerebral ischemia/reperfusion injury seemed to be within 5h after reperfusion. By up-regulating the expression of Nrf2/HO-1 pathway might be involved in the therapeutic mechanism of breviscapine injection.

Two new constituents from Erigeron breviscapus

Two novel constituents, named erigeronones A (1) and B (2), together with apigenin-7-O-β-galacturonide (3), quercetin-7-O-β-glucuronide (4), quercetin-3-O-β-galacturonide (5), and eriodictyol-7-O-β-glucuronide (6), were isolated from the whole grass of Erigeron breviscapus (Vant) Hand.-Mazz (Compositae). Their structures were established on the basis of spectral analyses and comparison with the literature data. Both new compounds 1 and 2 possess a γ-pyrone moiety that is rare in nature. Compound 1 showed significant protective effect on H2O2-injured human umbilical vein endothelial cells.

[Simultaneous determination of chlorogenic acid, scutellarin, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid in different parts of Erigeron breviscapus by high-performance liquid chromatography]

OBJECTIVE

A high-performance liquid chromatographic (HPLC) method was developed for simultaneous determination of chlorogenic acid, scutellarin, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid in different parts of Erigerontis Herba.

METHOD

The four constituents were measured on an Agilent Zorbax SB-C18 column (4.6 mm x 450 mm, 5 microm) with a gradient elution of acetonitrile (A) -0.3% phosphoric acid solution (B) (0-10 min, 12%-15% A, 10-32 min, 15% A, 32-33 min, 15%-20% A, 33-50 min, 20%-22% A) at wavelength of 335 nm and 327 nm, and a flow rate of 1.0 mL x min(-1) and the column temperature was 30 degrees C.

RESULT

Linearity of each standard was established in the concentration range of 0.050 1-1.002 microg for chlorogenic acid, 0.165 9-3.318 microg for chlorogenic acid, 0.049 7-0.994 microg for 3,5-dicaffeoylquinic acid, 0.048 7-0.974 p.g for 4,5-dicaffeoylquinic acid respectively, with correlation coefficient r > 0.999 6. Average recoveries (n = 6) of 4 compounds were 98.53% with a RSD of 0.94%, 99.68% with a RSD of 0.49%, 98.78% with a RSD of 1.1%, 99.06% with a RSD of 0.81%, respectively.

CONCLUSION

The developed method is simple, accurate, and precise, it can be used for the quantitative analysis of Erigeron breviscapus.

[Two novel isocoumarins from Erigeron breviscapus]

Two novel isocoumarins, erigeronone C (1) and D (2), were isolated from the ethanol extract of the whole plant of Erigeron breviscapus (Vant.) Hand.-Mazz (Compositae). Their structures were respectively elucidated as 8, 9-dihydroxypyrano [3, 2-c] isochromen-4, 6-dione (1) and 4, 7-dihydroxy-3-(3-hydroxy-4-oxo-4H-pyran-2-yl)-1H-isochromen-1-one (2) on the basis of spectral analyses. Both structures of 1 and 2 possess a gamma-pyrone moiety and that is rare in natural products.

Pharmacokinetic interaction between scutellarin and valsartan in rats

Scutellarin is the main effective constituent of breviscapine, a flavonoid mixture isolated from the dried whole plant of Erigeron breviscapus (Vant.) Hand-Mazz, and valsartan is used as an antihypertensive drug. These two drugs have already been clinically used together to treat diabetic nephropathy (DN) in China, and the combined medications showed some enhanced protection against DN. The aim of this study is to investigate the potential pharmacokinetic interaction between scutellarin and valsartan in rats. Breviscapine injection (20 mg x kg(-1), i.v.) and valsartan (15 mg x kg-, i.g.), either alone or together were given to 18 male Sprague-Dawley rats. Concentrations of scutellarin and valsartan were quantified by HPLC, and pharmacokinetic parameters were calculated by non-compartmental methods. We found that the pharmacokinetic parameters of scutellarin altered significantly after co-administration of oral valsartan. The plasma clearance (CL(p)) and the bile clearance (CL(b)) of scutellarin were reduced significantly in the presence of valsartan. After oral administration of valsartan with or without intravenous scutellarin, however, the pharmacokinetic parameters of valsartan were comparable. In conclusion, our data suggests that the concurrent use of valsartan reduces the biliary excretion of scutellarin, and this may be due to the inhibitory effect of valsartan on the biliary excretion of scutellarin mediated by Mrp2 (Multidrug resistance-associated protein 2).

[Progresses on pharmacological and toxicological effects of Dengzhanxixin injection]

Dengzhanxixin injection is extracted from herbs of Erigeron breviscapusis. Its function includes activate blood, dispel stasis, unblock the collaterals and relieve pain. In clinical, it is widely used for static blood obstruction, wind-stroke and hemiplegia, numbness of limbs, deviated eyes and mouth, dysphasia, chest impediment, heart pain, ischemic stroke, coronary heart disease, and angina pectoris with the pattern mentioned above. In this paper, we planed to review the pharmacological and toxicological effects of Dengzhanxixin injection from relevant studies.

[Influence of Erigeron breviscapus on the expression of collagen type I , MMP1 and TIMP1 of MRC-5 cells under hypoxia]

OBJECTIVE

Study the influence of Erigeron breviscapus on collagen type I, matrix metalloproteinase1 (MMP1) and tissue inhibitor of metalloproteinase1(TIMP1) in human embryo lung fibroblast MRC-5 under hypoxia.

METHODS

MRC-5 cultured in vitro were individed into 4 groups, including normoxia control, hypoxia, hypoxia and staurosporine (SP), hypoxia and erigeron breviscapus. The expression of hypoxia-inducible factor-1 alpha (HIF-1alpha), pro-collal and phospho-smad2 (p-smad2) were evaluated by Western blot. The level of collagen type I, MMP1 and TIMP1 in supernatant fluid were detected by ELISA.

RESULTS

Expressed pro-collalpha1, p-smad2 in MRC-5 cells under nomoxia were detected, but not HIF-lalpha. A low level of collagen type I, MMP1 and TIMP1 was also detected in the cell supernatant. In nomoxia secreted pro-collalpha1, p-smad2, collagen type I , MMP1 and TIMP1, hardly secreted HIF-lalpha. Under hypoxia, the expression of all of them was increased when compared with those of under nomoxia condition (P < 0.05). MMP1 expression was significantly further upregluted by pre-cubation with SP in hypoxia, however collagen type I, TIMP1 in supernatant fluid and pro-collalpha1, p-smad2 in cells were inhibited (P < 0.05, vs. hypoxia group). Treated with Erigeron breviscapus (12. 5 microg/mL, 50 microg/mL) under hypoxia condition, significantly reduced expression of pro-collalpha1, p-smad2, HIF-1alpha in MRC-5 cells and collagen type I, MMP1, TIMP1 in supernatant fluid were observed (P < 0.05, vs. hypoxia).

CONCLUSION

Erigeron breviscapus can decrase the expression of HIF-1alpha of MRC-5 cells under hypoxia condition by inhibit the expression of collagen type I and TIMP1 partly through the Smad2 signaling pathways.

[Optimize the preparation process of Erigeron breviscapus sustained-release pellets based on artificial neural network and particle swarm optimization algorithm]

OBJECTIVE

To optimize the preparation process of Erigeron breviscapus sustained-release pellets.

METHODS

A mathematical model of relationship between the independent variables and dependent variable of the preparation process of Erigeron breviscapus sustained-release pellets was established by using back-propagation (BP) artificial neural networks (ANN), and the preparation process parameters were optimized with particle swarm optimization (PSO) algorithm.

RESULTS

The pellets prepared according to the optimized preparation process parameters had significant effect of sustained-releasing. Drug release from the pellets was controlled by both diffusion and matrix corrosion.

CONCLUSION

Combining BP ANN modeling with PSO algorithm provides an effective way to solve the multi-dimensional optimization problem of complicated nonlinear systems in pharmaceutical technology.

In-line monitoring of extraction process of scutellarein from Erigeron breviscapus (vant.) Hand-Mazz based on qualitative and quantitative uses of near-infrared spectroscopy

The application of near-infrared (NIR) spectroscopy for in-line monitoring of extraction process of scutellarein from Erigeron breviscapus (vant.) Hand-Mazz was investigated. For NIR measurements, two fiber optic probes designed to transmit NIR radiation through a 2 mm pathlength flow cell were utilized to collect spectra in real-time. High performance liquid chromatography (HPLC) was used as a reference method to determine scutellarein in extract solution. Partial least squares regression (PLSR) calibration model of Savitzky-Golay smoothing NIR spectra in the 5450-10,000 cm(-1) region gave satisfactory predictive results for scutellarein. The results showed that the correlation coefficients of calibration and cross validation were 0.9967 and 0.9811, respectively, and the root mean square error of calibration and cross validation were 0.044 and 0.105, respectively. Furthermore, both the moving block standard deviation (MBSD) method and conformity test were used to identify the end point of extraction process, providing real-time data and instant feedback about the extraction course. The results obtained in this study indicated that the NIR spectroscopy technique provides an efficient and environmentally friendly approach for fast determination of scutellarein and end point control of extraction process.

Effects of scutellarin on MUC5AC mucin production induced by human neutrophil elastase or interleukin 13 on airway epithelial cells

Scutellarin is a flavonoid extracted from a traditional Chinese herb, Erigeron breviscapus. The present study investigated the effect of scutellarin on MUC5AC mucin production and the possible mechanism. Human bronchial epithelial 16 (HBE16) cells were pretreated with scutellarin for 60 min, and then exposed to human neutrophil elastase (HNE) or interleukin (IL)-13 for 12 hr. RT-PCR and ELISA were performed to measure the amount of MUC5AC mucin production. The results showed that scutellarin inhibited MUC5AC expression both in mRNA and protein level induced by HNE in a concentration-dependent manner. However, scutellarin failed to inhibit MUC5AC mucin production induced by IL-13. To investigate the intracellular mechanisms associated with the effect of scutellarin on MUC5AC mucin production, western blotting was carried out to examine the phosphorylation of protein kinase C (PKC), signal transducer and activator of transcription 6 (STAT6) and extracellular signal-regulated kinase 1/2 (ERK1/2). The phosphorylation of PKC and ERK1/2 was attenuated after treatment with scutellarin, whereas STAT6 was not significantly affected. Therefore, it is suggested that scutellarin down-regulates MUC5AC mucin production on HBE16 cells via ERK-dependent and PKC-dependent pathways.

[Chemical constituents from herbs of Erigeron breviscapus]

OBJECTIVE

To study the chemical constituents from herbs of Erigeron breviscapus.

METHOD

The compounds were isolated and purified by various chromatographic techniques. Their structures were identified on the basis of physicochemical properties and spectral analysis.

RESULT

Twelve compounds were isolated and structurally identified as quercetin-3-O-beta-D-glucoside (1), 5, 7-dihydroxychromone (2), 3-O-caffeoyl-gamma-quinide (3), naringenin (4), 3, 5-di-O-caffeoylquinic acid (5), 3,4-di-O-caffeoylquinic acid (6), 4, 5-di-O-caffeoylquinic acid (7), 1,3-di-O-caffeoylquinic acid (8), 1, 5-di-O-caffeoylquinic acid (9), 3-O-caffeoylquinic acid (10), 4-O-caffeoylquinic acid (11) and chlorogenic acid (12).

CONCLUSION

Compounds 1-4 were isolated from this plant for the first time.

[Effects of Erigeron breviscapus injection on TNF-alpha, PAI-1 and tPA in rats with acute myocardial infarction]

OBJECTIVE

To research the effects of Erigeron breviscapus injection (EBI) on TNF-alpha, PAI-1 and tPA in rats with acute myocardial infarction.

METHODS

Models of acute myocardial infarction (AMI)were produced by ligation of left anterior descending coronary artery, then rats were randomly divided into control and experimental groups, then respectively gavaged NS, and the low, middle and high dosage of EBI for one week. The cardiac function index and the expression of TNF-alpha, tPA and PAI-1 were measured.

RESULTS

Compared with the NS group, the cardiac function LVEDP, MAP, LVPmax, +/- dp/dt of AMI rat was improved by EBI in all dosage range, and the expression of TNF-alpha and PAI-1, LVEDP were decreased (P < 0.05), the expression of tPA, MAP, LVPmax and +/- dp/dt were increased obviously (P < 0.05) and had a dose-effect relationship.

CONCLUSION

EBI can inhibit the expression of TNF-alpha and PAI-1, increase the expression of tPA,which can prevent the ongoing thrombopoiesis after AMI and improve the cardiac function. This maybe attributes to the inhibition of the overexpression of TNF-alpha.

Rapid screening and identification of caffeic acid and its esters in Erigeron breviscapus by ultra-performance liquid chromatography/tandem mass spectrometry

Caffeic acid and its esters (CAEs) are widely distributed in the plant kingdom and have been reported to elicit a wide range of exceptional biological activities. Present methods for screening and characterization of CAEs normally need the use of liquid chromatography diode-array detection/multistage mass spectrometry (LC-DAD/MS(n)). In this report, a rapid and efficient method coupling ultra-performance liquid chromatography (UPLC) with fragment-targeted multi-reaction monitoring (MRM) has been developed for screening CAEs in a crude extract of Erigeron breviscapus, while a UPLC/quasi-MS(n) method has been applied in the structural identification of these compounds. Furthermore, a simple quasi-UPLC/MS/MS method based on in-source collision-induced dissociation (CID) has been proposed for rapid identification of the CAEs. As a result, a total of more than 34 CAEs were detected and their structures characterized. Nine of them were reported from E. breviscapus for the first time. Applications of these strategies in the chemical investigation of an injection of E. breviscapus resulted in the identifications of 16 CAEs. These strategies, if appropriate modifications are made, will be very useful in screening and characterization not only of CAEs, but of other structural types of compounds in various complex matrices.

[Study on the extraction of breviscapine from Erigeron breviscapus with ultrasonic wave technology optimized by central composite design-response surface method]

OBJECTIVE

To evaluate the effectiveness of ultrasound-assisted extraction and establish the optimized extraction conditions of breviscapine from Erigeron breviscapus.

METHODS

On the basis of the single factor and according to the central composite design principles (CCD), the response surface method (RSM) with 3 factors and 3 levels was adopted and the independent variables were ultrasonic wave extracting time, ethanol concentration, and the ratio of solvent volume to Erigeron breviscapus mass, breviscapine extraction yield determinated by HPLC was used as response value.

RESULTS

Ultrasonic wave extracting time of 24.5 min, ethanol concentration of 74.7% and the ratio of solvent volume to Erigeron breviscapus mass of 19.8 (mL/g) were selected as optimum conditions. Regression coefficients of binomial fitting complex model was 0. 9549 and the predicted breviscapine extraction yield was 0.641%, while the actual extraction yield was 0.632% (n = 5), with relative error of -1.14%.

CONCLUSION

This study confirms the efficiency of ultrasound-assisted extraction as a simple, inexpensive and effective method to improve the extraction of breviscapine from Erigeron breviscapus. The observed and predicted values are close to each other, which proves that the optimization of supersonic extraction process of breviscapine from Erigeron breviscapus by CCD-RSM is reasonable and successful.

GC-MS analysis, antibacterial activity and genotoxic property of Erigeron mucronatus essential oil

GC-MS analysis of the hydrodistilled oil of Erigeron mucronatus DC was carried out, after the separation of a crystalline compound, lachnophyllum cumulene. Twenty-four components were identified. The oil contained 59.6% sesquiterpenoids, 16.1% monoterpenoids and 24.3% poly-acetylenic esters. Among the mono and sesquiterpenoids, limonene (10.3%) and caryophyllenes (11.4%) were the major constituents. The essential oil also revealed the unusual presence of both cis (8.3%) and trans (1.1%) methyl lachnophyllum esters. Seasonal variation in the yield of E. mucronatus oil was observed. The yield varied from 0.49 to 0.58%, being highest during the rainy season. Antimicrobial activity was assessed using a method based on zones of inhibition; the oil exhibited maximum anti- bacterial activity against both Staphylococcus aureus and Escherichia coli, but moderate activity against Pseudomonas aeruginosa. Genotoxicity of the oil was determined in AB blood serum at different concentrations and hours of exposure. The antibacterial activity of the oil and its insignificant genotoxicity at low concentrations make the oil a good candidate as a curative agent.

[Formula screening and optimizing for the dispersible tablets of breviscapine by orthogonal experiment]

OBJECTIVE

To establish a suitable formulation for the dispersible tablets of brevisicapine.

METHODS

To prepare and optimize the breviscapine dispersible tablets by orthogonal experiment design using disintegration time as the index. The quality of breviscapine dispersible tablets was evaluated by the initial stability test.

RESULTS

The disintegration time of optimized prescription formulation was 89 s. L-HPC and CMS-Na were used by combining exterior and interior and the dissolution percent in vitro was obviously superior to the conventional tablets, and the quality of the dispersible tablets was very good in stability test.

CONCLUSION

The formulation screened out for the dispersible tablets of breviscapine is reasonable, stable and suitable for the production on a large scale.

[FTIR spectra-principal component analysis of Erigeron breviscapus and Erigeron multiradiatus from different areas]

Erigeron breviscapus and erigeron multiradiatus, belonging to compositae, have been widely used as "meiduoluomi" in traditional Tibetan medicine for treatment of heat-clearing and detoxicating. However, it is difficult to distinguish them because of similarity of morphology. Therefore, the chemotaxonomy method was established. FTIR fingerprint spectra of E. breviscapus and E. multiradiatus samples from 13 geographical origins were studied. The results demonstrated that they could be divided into 2 classes with principal component analysis (PCA). The classification was well correlated to their gene, geographical origins and weather. In the same class, the chemical components are similar to each other, which can be considered as the criterion for evaluating their quality. The results showed that their infrared spectra characteristic of the same species was similar in the range of 4 000-450 cm(-1), but varied significantly for different species. The method is rapid and simple, and could be applied to evaluate the quality of this traditional medicine.

Estrogenic and neuroprotective properties of scutellarin from Erigeron breviscapus: a drug against postmenopausal symptoms and Alzheimer's disease

Besides the classical hormonal effect, estrogen possesses neuroprotective effects in the brain, which leads to the searching of novel treatments for neurodegenerative diseases such as Alzheimer's disease. Scutellarin is a major flavone derived from Herba Erigerontis, a Chinese medicine derived from Erigeron breviscapus, which has been shown here to possess both estrogenic and neuroprotective properties. Scutellarin showed the estrogenic effects by activating the estrogen responsive elements and phosphorylation of estrogen receptor alpha in cultured MCF-7 cells: the activation was in a dose-dependent manner. On the other hand, scutellarin inhibited the aggregation of beta-amyloid in vitro, and prevented the cell death mediated by beta-amyloid when applied to cultured neuronal PC12 cells. These results therefore suggested that Herba Erigerontis and its component scutellarin might have therapeutic effects against postmenopausal symptoms and Alzheimer's disease.

[Effects of doubled CO2 concentration on Erigeron breviscapus growth and its active constituent accumulation]

With medicinal plant Erigeron breviscapus as test material, its biomass and the contents and yields of scutellarin and caffeate were monitored under doubled (800 +/- 100) micromol x mol(-1) and natural (400 +/- 25) micromol x mol(-1) CO2 concentration. Comparing with those under natural CO2 concentration, the biomass of E. breviscapus under doubled CO2 concentration increased by 22%, the contents of scutellarin and caffeate increased by 23% and 26%, and the yields of these two constituents increased by 37.6% and 45.3%, respectively. Different organs had different responses in their biomass and active constituent contents to the elevated CO2 concentration. Under doubled CO2 concentration, the plant N content decreased by 47.2% and was negatively correlated with active constituent contents, being accorded well to the C/N balance hypothesis, and the biomass was positively correlated with the active constituent contents while no trade-off was observed between plant growth and secondary metabolism, suggesting that rational application of CO2 could improve the yield and quality of E. breviscapus.

[Comparison of the distribution of breviscapine in the brain by different administration routes]

By comparing the drug distribution of breviscapine administered intranasally, orally and intrgvenous injected in rats' brain. After 0.4 mg x kg(-1) breviscapine was given by tail vein, intranasal and gastric perfusion administration to SD rats, cerebrospinal fluid was obtained by erebellomedllery cisternal puncture at different times. 125I labeling was used to determine the drug content of cerebrospinal fluid, cerebrum, cerebellum, medulla oblongata, olfactory region, olfactory bulb and blood in rats. AUCs were calculated by trapezoidal rule. The results showed that AUCs(0-240 min) (microg x min x g(-1)) of brain tissues were 11.686 +/- 1.919, 5.676 +/- 1.025, 7.989 +/- 0.925, 7.956 +/- 1.159, 17.465 +/- 2.136, 24.2 +/- 2.906 and 78.51 +/- 12.05, respectively, in the intranasal administration group; while those in the tail vein administration groups were 6.79 +/- 0.661, 6.251 +/- 0.40, 10.805 +/- 1.161, 9.146 +/- 1.04, 9.892 +/- 1.532, 7.871 +/- 0.842 and 173.91 +/- 10.02; and oral administration group were 0.868 +/- 0.167, 1.708 +/- 0.266, 2.867 +/- 0.725, 2.067 +/- 0.313, 1.361 +/- 0.308, 1.206 +/- 0.255 and 45.2 +/- 7.52, respectively. AUCs(0-240 min) of the brain tissues after oral, tail vein and intranasal administration were 22.29%, 29.18%, 95.49% of that of blood, respectively, it means that the absorption rate and drug distribution in the brain tissues after intranasal administration were higher than those of oral and tail vein administration. It is worth to investigate further the pharmacodynamic relationship.

[Effect of water stress on content of active constituents in Erigeron breviscaps]

OBJECTIVE

To study the effect of water stress on the content of scutellarin and caffeate in Erigeron breviscaps.

METHOD

Fv/Fm, N content, as well as the content of scutellarin and caffeate under three water grads were measured.

RESULT AND CONCLUSION

Fv/Fm of the plant decreased significantly in 8% and 23% water treatment, that proved drought and waterlogging occurred. Under the two conditions, the contents of N were lower but the contents of active constituents were higher than those under 15% treatment. The results support the carbon-nutrient balance hypothesis and the "stress effect hypothesis" for the formation of geo-herbs.

Breviscapine improves functions of spatial learning and memory of focal cerebral ischemia rats

OBJECTIVE

To investigate the effects of breviscapine on the functions of spatial learning and memory of focal cerebral ischemia rats.

METHODS

Rots withl the left middle cerebral artery occluded were made by an intraluminal filament. Then breviscapine (20 mg/kg,40 mg/kg) in experimental group and 10% glucose in control group were administered intraperitoneally once a day for 2 weeks, and the Morris water maze tasks were carried out for 5 days.

RESULTS

Compared with sham-operation group,the animals of ischemia-control group exhibited seriously impaired spatial learning and memory in both place navigation test and spatial probe test. In the place navigation test, the mean value of escape latency in breviscapine group was significantly shorter than that in ischemia control group (P < 0.01 for lower-dose and P < 0.05 for higher-dose breviscapine group, respectively). In the spatial probe test,compared with sham-operation (P < 0.01) and breviscapine group (P < 0.01), the rats of ischemia-control group spent more time in the no-former platform quadrant, and showed reduced frequency of crossing former platform site significantly. The numbers of neurons with Nissl staining and choline acetyltransferase (ChAT) immunopositive neurons in ipssilateral cortex in the breviscapine group were significantly more than those in the ischemia-control group (P < 0.01). In hippocampus, the numbers of neurons with Nissl staining and ChAT immunopositive neurons in the stratum pyramidale of CA area were similar among the groups.

CONCLUSION

These results indicate that breviscapine can improve the functions of spatial learning and memory of focal cerebral ischemia rats and the protection against the loss of ChAT immunopositive neuron in new cortex may be involved in its mechanisms.

[The effect of polyamidoamine (PAMAM) dendrimers on the solubility and pharmacokinetics of breviscapine]

To study the solubilization of breviscapine with polyamidoamine (PAMAM) dendrimers and probe the solubilizing mechanism and investigate the influence of PAMAM dendrimers on the pharmacokinetics of breviscapine, the solubilization of breviscapine by PAMAM dendrimers of generations G1, G1.5, G2 and G2.5 with different concentrations were determined and compared in different pH conditions. Twelve rats randomized into 2 groups were separately orally administered breviscapine and breviscapine combining with PAMAM. Drug in plasma was extracted and determined with HPLC. In pH condition lower than 7.0, the solubilization of breviscapine by PAMAM dendrimers enhanced as the generation and concentration of PAMAM dendrimers as well as the pH increased. Its solubilizing mechanism involves an electrostatic interaction between the carboxyl group of breviscapine and the primary amines and tertiary amines of PAMAM dendrimers. The pharmacokinetics parameters Cmax and AUC0-8 h of breviscapine were (119.65 +/- 9.36) ng x mL(-1) and (370.09 +/- 63.08) ng x h x mL(-1). For breviscapine combined with PAMAM dendrimers, the Cmax and AUC0-8 h were (518.17 +/- 17.07) ng x mL(-1) and (1,219.47 +/- 201.87) ng x h x mL(-1), respectively. There were significant differences of AUC0-8 h between breviscapine and breviscapine combined with PAMAM dendrimers (P < 0.01). PAMAM dendrimers can greatly increase the solubility of breviscapine in water and can improve the oral bioavailability of breviscapine significantly.

[Study on optimal harvest time of Erigeron breviscapus]

OBJECTIVE

To ascertain the optimal harvest time of Erigeron breviscapus.

METHOD

The dry matter weight accumulation of different organs in growth process and contents of scutellarin and coffeic acid ester in whole plant of E. breviscapus were determined.

RESULT

The number of leaves per plant, the dried weight of single leaf and dry matter weight of whole plant and different organs reached the highest after seedling 130-140 d. The content of scutellarin gradually decreased with growth period, and sharply decreased after seedling 140 d. The content of coffeic acid ester varied irregularly with growth period.

CONCLUSION

The optimal harvest time of E. breviscapus is in early bloom period after seedling 130 d.

Anti-inflammatory activity of the extracts and fractions from Erigeron multiradiatus through bioassay-guided procedures

ETHNOPHARMACOLOGICAL RELEVANCE

Erigeron multiradiatus (Lindl.) Benth., an herb that grows in the alpine and subalpine meadow of Qinghai-Tibet plateau, has been widely used as a folk remedy by the native people for treatment of various inflammatory ailments.

AIM OF THE STUDY

In order to isolate and identify the active components of Erigeron multiradiatus for anti-inflammatory activity, a preliminary phytochemical study and a bioassay-guided fractionation and purification process was performed.

MATERIAL AND METHODS

The dry whole plant Erigeron multiradiatus was extracted with 50% ethanol and then separated into CHCl(3), n-BuOH, and aqueous fractions. The anti-inflammatory activities of each fraction were investigated using two in vivo inflammation models.

RESULTS

These results exhibited varying degrees of anti-inflammatory activities and the n-BuOH fraction showed the strongest anti-inflammatory activities. The n-BuOH fraction was then subjected to separation and purification using macroporous resins column chromatography and Sephadex LH-20 leading to two flavonoids glucuronides identified as scutellarein-7-O-beta-glucuronide and apigenin-7-O-beta-glucuronide. Furthermore, LC-MS/MS identification and quantification of isolated compounds were also performed.

CONCLUSION

Scutellarein-7-O-beta-glucuronide and apigenin-7-O-beta-glucuronide were considered as major components and principally responsible for the anti-inflammatory activity of Erigeron multiradiatus. Thus the results of our study provide a scientific basis for the utilization of Erigeron multiradiatus in traditional Tibetan medicine.

[Studies on the constituents from the herba of Erigeron acer]

OBJECTIVE

To investigate the chemical constituents of the aerial part of Erigeron acer.

METHODS

The chemical constituents were isolated by various columns and thin layer chromatographic methods. The structures were identified by spectral data.

RESULTS

Five compounds were isolated and identified as alpha-amyrin (1), beta-amyrin (2), caffeic acid (3), quercetin (4), 4'-hydroxywogonin-7-O-beta-D-glucuronic acid glycoside (5).

CONCLUSION

The five compounds are obtained from this plant for the first time. The signals of 13C-NMR of the compound(5) are reassigned by means of DEPT, HMQC, HMBC, the signals of 1H-NMR of 2" - 5"-H of the glucuronic acid moiety are assigned by means of HMBC, HMQC, 1H-1H COSY for the first time.

Erigeroflavanone, a flavanone derivative from the flowers of Erigeron annuus with protein glycation and aldose reductase inhibitory activity

A novel 2,3-dioxygenated flavanone, erigeroflavanone ( 1), as well as eight known flavonoids and two known gamma-pyranone derivatives, were isolated from an ethyl acetate-soluble extract of the flowers of Erigeron annuus. The structure of compound 1 was elucidated by interpretation of spectroscopic data. All of the isolates were subjected to in vitro bioassays to evaluate their inhibitory activity against advanced glycation end products formation and rat lens aldose reductase.

[Effects of erigeron injection on renal interstitial fibrosis in rats]

OBJECTIVE

To investigate the effect and mechanism of Erigeron Injection (EI) on renal interstitial fibrosis in rats.

METHODS

Unilateral ureteral obstruction (UUO) model rats were taken as the subject of study. Thirty-six Sprague-Dawley rats were randomly divided into the control group (A), the UUO model group (B) and the treatment group (C) treated with intraperitoneal injection of EI 5 mL/kg per day from 24 h before to 9 days after the operation. On the 10th day of UUO, rats were killed and their kidneys were processed to paraffin sections with HE, PAS and picro-sirius-red staining. The pathological change of renal tubular interstitial tissue and relative cortical/interstitial volume (C/I) as well as the relative content of collagen (RC) were observed by light microscope. The expression of transforming growth factor beta1 (TGF-beta1), alpha-smooth muscle actin (alpha-SMA) and collagen I in the renal mesenchyma were examined by immunohistochemistry.

RESULTS

Marked renal interstitial fibrosis changes were found in Group B and C, but the changes were milder in Group C. C/I and RC were higher in Groups B and C as compared with those in Group A (P < 0.01), but they were much lower in Group C than in Group B (P < 0.01). The expression of TGF-beta1, alpha-SMA and collagen I were higher in Group B and C than those in Group A (P < 0.05), but they were lower in Group C than in Group B (P < 0.05).

CONCLUSION

EI could ameliorate renal interstitial fibrosis in rats, which might be partially realized by down-regulating the expression of TGF-beta1 to prevent the renal epithelial cell differentiation and reducing the synthesis of collagen I.

Inhibitory effect of Erigeron breviscapus extract and its flavonoid components on GABA shunt enzymes

Gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter, is metabolized by the successive action of GABA transaminase (GABA-T) and succinic semialdehyde dehydrogenase (SSADH). Inhibition of both enzymes in brain tissues increases the GABA level and may have therapeutic applications in neurological diseases. Erigeron breviscapus ethanol extract was evaluated for their effect on both enzymes. This extract, its ethyl acetate fraction and aqueous fraction, significantly inhibited them at >100 microg/ml. Flavonoid components of E. breviscapus potently and noncompetitively inhibited both enzymes, and the different structure-activity relations were observed with respect to inhibition of both enzymes. Baicalein was the most potent inhibitor for GABA-T with an IC50 value of 12.8+/-1.2 microM, and scutellarein exhibited the best inhibitory effect on SSADH with an IC50 value of 7.20+/-0.9 microM. The present results may imply new pharmacological actions of E. breviscapus and contribute partially to the beneficial effect of the herb and flavonoids on the central nervous system.

Effects of scutellarin on PKCgamma in PC12 cell injury induced by oxygen and glucose deprivation

AIM

To evaluate the neuroprotective effect and mechanisms of scutellarin (Scu) against PC12 cell injury after oxygen and glucose deprivation followed by reperfusion (OGD-Rep).

METHODS

Undifferentiated rat pheochromocytoma PC12 cells, exposed to oxygen and glucose deprivation followed by reperfusion (OGD-Rep), used as an in vitro model of ischemia/reperfusion. Cell survival was evaluated by diphenyltetrazolium bromide (MTT) assay and the amount of LDH release was determined using assay kits. [Ca2+](i) was monitored using a fluorescent Ca2+-sensitive dye Fura-2 acetoxymethyl ester. Cell apoptosis was detected by a DNA ladder and by flow cytometric detection. The expression of protein kinase C (PKC)gamma was determined using both RT-PCR and Western blotting. The translocation of PKCgamma was assayed by subcellular fractionation and Western blotting.

RESULTS

OGD-Rep injury significantly elevated the level of LDH release, [Ca2+](i), mRNA expression and the translocation of PKCgamma compared in the PC12 cells with those of the normal group. Scu (10-100 micromol/L) exerted a protective effect against OGD-Rep injury by reducing LDH release, [Ca2+](i), the percent of apoptosis, and the translocation of PKCgamma.

CONCLUSION

Scu inhibits the increase of [Ca2+](i) and the activation of PKCgamma, exerting protective effects against PC12 cell injury induced by OGD-Rep.

Separation of scutellarin from crude extracts of Erigeron breviscapus (vant.) Hand. Mazz. by macroporous resins

Scutellarin, a flavone glycoside, popularly used in the treatment of heart disease, has been efficiently separated using macroporous resins from crude extracts of Chinese medicinal plant Erigeron breviscapus (vant.) Hand. Mazz. HPD-800 resin offered the best adsorption and desorption capacity for scutellarin among the eight macroporous resins tested, and its adsorption data at 25 degrees C fit best to the Langmuir isotherm. The dynamic adsorption and desorption experiments have been carried out on a HPD-800 resin packed column to optimize the separation process of scutellarin from the crude extracts of E. breviscapus. After one run treatment with HPD-800 resin, the scutellarin content in the product was increased 15.69-fold from 2.61% to 40.96% with a recovery yield of 95.01%. The preparative separation process via adsorption-desorption method developed in this study provides a new approach for scale-up separation and purification of scutellarin for its wide pharmaceutical use.

[Identification model of cultivated and wild Chinese medical herbs erigeron breviscapus with near-infrared spectroscopy]

Forty three cultivated and wild Chinese medical herbs erigeron breviscapus were scanned on two Fourier transform near-infrared spectroscopy instruments. Twenty samples were used to set up the BP-NN models and the others were used to validate the models. Fifteen principal components, whose variance contribution rate is above 99%, were collected as input nodes for BP-NN models. The correct identification rates of calibration samples were 100% for the models on both the two instruments, and the correct identification rates of validation samples were 100% and 95.7%, irrespectively. The results showed that using NIR to fast detect cultivated and wild Chinese medical herbs erigeron breviscapus was feasible.

[Study on RP-HPLC fingerprint of xinshao injection]

OBJECTIVE

To establish the fingerprint detecting standard of xinshao Injection by reversed phase high performance liquid chromatography.

METHOD

The chromatographic conditions were as follows: an Diamonsil C18 column was used, the mobile phase was composed of 80% acetontrile and 0.1% phosphoric acid with gradient elution, the flow rate 1.0 mL min(-1), column temperature was 40 degrees and the UV absorbance detection was set at 230 nm.

RESULT

A standard HPLC fingerprint procedure was developed for xinshao Injection, with 8 common peaks. Under the same selected chromatographic conditions, the HPLC fingerprints of raw drugs and their intermediate, finished products were obtained with good separation and correlation (no less than 0.97) according to the technical requirements of fingerprint on Injection of Chinese traditional medicine.

CONCLUSION

This method was accurate, repeatable and can be used as the important parameters of the quality control for xinshao injection.

Microwave-assisted extraction of scutellarin from Erigeron breviscapus Hand-Mazz and its determination by high-performance liquid chromatography

An efficient microwave-assisted extraction (MAE) technique has been developed to extract scutellarin from Erigeron breviscapus for rapid determination by high-performance liquid chromatography (HPLC). The maximum yield of scutellarin reached 1.02% in 40 min under the optimal MAE conditions with 80 degrees C of extraction temperature and 1:10 (w/v) of the solid/liquid ratio. The MAE showed obvious advantages in terms of short duration and high efficiency to extract scutellarin in comparison with heat-flux extraction. The mechanism of the enhanced extraction by microwave assistance was discussed by detecting particle size and specific surface area of plant materials and observing cell destruction of plant material by light microscopy and scanning electron microscopy. The results showed that the plant materials were significantly destroyed due to the cell rupture after MAE treatment. Afterward, the method validation for HPLC-UV analysis was developed. Calibration range was 0.1-100 microg mL(-1) for scutellarin, and correlation coefficient R was 0.9993. Limit of detection was less than 0.01 microg mL(-1). The intra- and inter-day relative standard deviation (R.S.D.) of scutellarin detection ranged from 1.58% to 2.96% and from 3.32% to 4.19%, respectively. The recovery of the method for scutellarin ranged from 96.7% to 101.9%.