Protective effects of Eucommia ulmoides Oliv. bark and leaf on amyloid β-induced cytotoxicity

Insights on therapeutic approaches of natural anti-Alzheimer's agents in the management of Alzheimer's disease: A future perspective

In the current scenario, Alzheimer's disease is a complex, challenging, and arduous health issue, and its prevalence, together with comorbidities, is accelerating around the universe. Alzheimer's disease is becoming a primary concern that significantly impacts an individual's status in life. The traditional treatment of Alzheimer's disease includes some synthetic drugs, which have numerous dangerous side effects, a high risk of recurrence, lower bioavailability, and limited treatment. Hence, the current article is a detailed study and review of all known information on plant-derived compounds as natural anti-Alzheimer's agents, including their biological sources, active phytochemical ingredients, and a possible mode of action. With the help of a scientific data search engine, including the National Center for Biotechnology Information (NCBI/PubMed), Science Direct, and Google Scholar, analysis from 2001 to 2024 has been completed. This article also described clinical studies on phytoconstituents used to treat Alzheimer's disease. Plant-derived compounds offer promising alternatives to synthetic drugs in treating Alzheimer's disease, with the potential for improving cognitive function and slowing down the progression of the disease. Further research and clinical trials are needed to fully explore their therapeutic potential and develop effective strategies for managing this complex condition.

Total Flavonoids Isolated from the Leaves of Eucommia ulmoides Augment Peak Bone Mass in Female Rats and Show no Side Effects in Other Organs

INTRODUCTION

Eucommia ulmoides is a unique monophyletic and tertiary relict in China and is listed as a national second-class precious protected tree species. Eucommia ulmoides, recognized as a traditional Chinese medicine, can tonify the liver and kidneys and strengthen bones and muscles. Modern pharmacological research has proved that Eucommia ulmoides has multiple osteoprotective effects, including prohibiting the occurrence of osteoporosis and arthritis and enhancing the healing of bone fractures and bone defects.

AIM

To check its osteotropic effects, which may provide ideas for its potential use for the development of novel drugs to treat osteoporosis, this study evaluated the effect of total flavonoids from Eucommia ulmoides leaves (TFEL) on the acquisition of Peak Bone Mass (PBM) in young female rats.

MATERIALS AND METHODS

TFEL was isolated, and its purity was confirmed by using a UV spectrophotometer. TFEL with a purity of 85.09% was administered to 6-week-old female rats by oral gavage at a low (50), mid (100), or high (200 mg/kg/d) dose, and the control group was administrated only with the same volume of water. After 13 weeks of treatment, the rats were sacrificed, and serum, different organs, and limb bones (femurs and tibias) were harvested, and the bone turnover markers, organ index, Bone Mineral Density (BMD), biomechanical property, and microstructure parameters were assayed. Furthermore, molecular targets were screened, and network pharmacology analyses were conducted to reveal the potential mechanisms of action of TFEL.

RESULTS

Oral administration of TFEL for 13 weeks decreased the serum level of bone resorption marker TRACP-5b. As revealed by micro-computer tomography analysis, it elevated BMD even at a low dose (50 mg/kg/d) and improved the microstructural parameters, which were also confirmed by H&E histological staining. However, TFEL showed no effects on body weights, organ index, and micromorphology in the uterus. In our network pharmacology study, an intersection analysis screened out 64 shared targets, with quercetin, kaempferol, naringenin, and apigenin regulating the greatest number of targets associated with osteoporosis. Flavonoids in Eucommia ulmoides inhibited the occurrence of osteoporosis potentially through targeting signaling pathways for calcium, VEGF, IL-17, and NF-κB. Furthermore, AKT1, EGFR, PTGS2, VEGFA, and CALM were found to be potentially important target genes for the osteoprotective effects of flavonoids in Eucommia ulmoides.

CONCLUSION

The above results suggested that TFEL can be used to elevate the peak bone mass in adolescence in female individuals, which may prevent the occurrence of postmenopausal osteoporosis, and the good safety of TFEL also suggests that it can be used as a food additive for daily life to improve the bone health.

Geniposidic acid attenuates DSS-induced colitis through inhibiting inflammation and regulating gut microbiota

Geniposidic acid (GPA) is a bioactive compound isolated from Gardenia jasminoides Ellis (Rubiaceae) that has long been used to treat arthritis, jaundice, and hypertension. However, the therapeutic effects of GPA against colitis remain underexplored. This study aimed to investigate the effect of GPA on the remission of colitis and the underlying mechanisms. A DSS-induced colitis mouse model was used to evaluate the influence of GPA on the modulation of gut microbiota and intestinal epithelial barrier function. Our results indicated that GPA improved DSS-induced mouse colitis, including loss of body weight, disease activity index (DAI), colon length, and colonic pathological damage. DSS-induced destruction of the intestinal barrier was also significantly repaired by GPA treatment. In addition, the relative levels of pro-inflammatory cytokines, such as IL-1β and TNF-α, were markedly alleviated by GPA. Furthermore, western blot analysis revealed that GPA downregulated the protein expression of the nuclear transcription factor NF-κB. Finally, we first demonstrated that GPA could alleviate gut microbiota dysbiosis in mice with colitis by bacterial 16S rRNA sequencing. In conclusion, our study demonstrates the therapeutic and protective effects of GPA on IBD and provides novel insights into the prevention of colitis by targeting gut microbiota metabolism using natural products.

Eucommiae Folium and Active Compounds Protect Against Mitochondrial Dysfunction-Calcium Overload in Epileptic Hippocampal Neurons Through the Hypertrophic Cardiomyopathy Pathway

Epilepsy is a chronic brain disease and often occurs suddenly for no reason. Eucommiae folium (EF), an edible herb, can be used in the treatment of various kinds of brain diseases in clinic. From the perspective of safety and efficacy, EF is especially suitable for the treatment of chronic brain diseases. With the help of biolabels, this study was aimed to explore the value and feasibility of EF in the treatment of epilepsy. Proteomics and metabolomics were used to explore the biolabels of EF intervention in brain tissues. Bioinformatics was then applied to topologically analyze its neuroprotective effects and mechanisms and material basis based on biolabels, which were validated in an animal model. The biolabel-led research revealed that EF may exert the therapeutic potential to treat brain diseases through the interaction between multiple compounds and multiple targets, among which its therapeutic potential for epilepsy is particularly prominent. In the pentylenetetrazole-induction model, EF and four active compounds (oleamide, catechol, chlorogenic acid, and kaempferol) protected epileptic hippocampal neurons (Nissl and FJB staining) against mitochondrial dysfunction (MYH6, MYL3, and MYBPC3, etc.) and calcium overload (TNNI3, TNNC1, and TNNT2, etc.) through the hypertrophic cardiomyopathy pathway. This study provides new evidence and insights for the neuroprotective effects of EF, in which four active compounds may be potential drug candidates for the treatment of epilepsy.

Anti-Inflammatory Effects of Geniposidic Acid on Porphyromonas gingivalis-Induced Periodontitis in Mice

Periodontal disease is predominantly caused by the pathogenic bacterium Porphyromonas gingivalis that produces inflammation-inducing factors in the host. Eucommia ulmoides is a plant native to China that has been reported to reduce blood pressure, promote weight loss, and exhibit anti-inflammatory effects. Geniposidic acid (GPA) is the major component of E. ulmoides. Herein, we investigated the effects of GPA on P. gingivalis-induced periodontitis by measuring the inflammatory responses in human gingival epithelial cells (HGECs) after P. gingivalis stimulation and GPA addition in a P. gingivalis-induced periodontitis mouse model. We found that GPA addition suppressed interleukin (IL)-6 mRNA induction (33.8% suppression), IL-6 production (69.2% suppression), toll-like receptor (TLR) 2 induction, and mitogen-activated protein kinase (MAPK) phosphorylation in HGECs stimulated by P. gingivalis. Inoculation of mice with GPA inhibited P. gingivalis-induced alveolar bone resorption (25.6% suppression) by suppressing IL-6 and TLR2 production in the serum and gingiva. GPA suppressed osteoclast differentiation of bone marrow cells induced by M-CSF and sRANKL in mice (56.7% suppression). GPA also suppressed the mRNA expression of OSCAR, NFATc1, c-Fos, cathepsin K, and DC-STAMP. In summary, GPA exerts an anti-inflammatory effect on periodontal tissue and may be effective in preventing periodontal disease.

Effect of Ethyl Acetate Fraction from Eucommia ulmoides Leaves on PM2.5-Induced Inflammation and Cognitive Dysfunction

This study aimed to evaluate the protective effect of the ethyl acetate from Eucommia ulmoides leaves (EFEL) on PM2.5-induced cognitive impairment in BALB/c mice. EFEL improved PM2.5-induced cognitive decline by improving spontaneous alternative behavioral and long-term memory ability. EFEL increased ferric reducing activity power (FRAP) in serum. In addition, EFEL increased superoxide dismutase (SOD) and reduced glutathione (GSH) contents and inhibited the production of malondialdehyde (MDA) in lung and brain tissues. EFEL also restored the mitochondrial function by regulating reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP) level, and ATP level in lung and brain tissues. EFEL ameliorated the cholinergic system by regulating the acetylcholine (ACh) content and acetylcholinesterase (AChE) activity in the brain tissue and the expression of AChE and choline acetyltransferase (ChAT) in the whole brain and hippocampal tissues. EFEL reduced PM2.5-induced excessive expression of inflammatory protein related to the lung, whole brain, olfactory bulb, and hippocampus. Physiological compounds of EFEL were identified as 5-O-caffeolyquinic acid, rutin, quercetin, and quercetin glycosides. As a result, EFEL has anti-inflammation and anti-amnesic effect on PM2.5-induced cognitive impairment by regulating the inflammation and inhibiting the lung and brain tissue dysfunction, and its effect is considered to be due to the physiological compounds of EFEL.

Mechanism of cell death pathways in status epilepticus and related therapeutic agents

The most severe form of epilepsy, status epilepticus (SE), causes brain damage and results in the development of recurring seizures. Currently, the management of SE remains a clinical challenge because patients do not respond adequately to conventional treatments. Evidence suggests that neural cell death worsens the occurrence and progression of SE. The main forms of cell death are apoptosis, necroptosis, pyroptosis, and ferroptosis. Herein, these mechanisms of neuronal death in relation to SE and the alleviation of SE by potential modulators that target neuronal death have been reviewed. An understanding of these pathways and their possible roles in SE may assist in the development of SE therapies and in the discovery of new agents.

The Regulatory effect of chlorogenic acid on gut-brain function and its mechanism: A systematic review

Chlorogenic acid (CGA) is a phenolic compound that is widely distributed in honeysuckle, Eucommia, fruits and vegetables. It has various biological functions, including cardiovascular, nerve, kidney, and liver protection, and it exerts a protective effect on human health, according to clinical research and basic research. The intestine and brain are two important organs that are closely related in the human body. The intestine is even called the "second brain" in humans. However, among the many reports in the literature, an article systematically reporting the regulatory effects and specific mechanisms of CGA on the intestines and brain has not been published. In this context, this review uses the regulatory role and mechanism of CGA in the intestine and brain as the starting point and comprehensively reviews CGA metabolism in the body and the regulatory role and mechanism of CGA in the intestine and brain described in recent years. Additionally, the review speculates on the potential biological actions of CGA in the gut-brain axis. This study provides a scientific theory for CGA research in the brain and intestines and promotes the transformation of basic research and the application of CGA in food nutrition and health care.

Optimization of the Extraction Technology and Assessment of Antioxidant Activity of Chlorogenic Acid-Rich Extracts From Eucommia ulmoides Leaves

Chlorogenic acid has been proved to have cardiovascular protection, antibacterial, antiviral, hemostatic, and hypolipidemia effects. Modern scientific research on the bioactivity of chlorogenic acid has been extended to the fields of food, medicine, health care and daily-use chemical industry. The aim of this research was to optimize the extraction conditions for chlorogenic acid from Eucommia ulmoides (Eucommiaceae) leaves. The significant variables were screened and optimized by a combination of Plackett-Burman test and Box-Behnken design. Optimum extraction parameters with ethanol concentration of 50%, solvent pH value of 3, and particle size of 60 mesh were determined according to variance analysis and contour plots. Under these conditions, the yield of chlorogenic acid was up to 4.36 mg/g, which was basically consistent with the theoretical prediction value of 4.50 mg/g. This study also proved the potential antioxidant activity of E. ulmoides leaves. The optimal extract of E. ulmoides leaves rich in chlorogenic acid showed the highest antioxidant activity in the FRAP method, which was 219.8 μM Trolox equivalents (TE) per g extract weight (EW) (μM TE/g EW). The DPPH method gave a similar value (168 μM TE/g EW) to the ABTS method (152 μM TE/g EW). The established extraction process was efficient in the recovery of chlorogenic acid from E. ulmoides leaves, encouraging its valorization as a cheap and sustainable alternative for the isolation of chlorogenic acid.

Traditional application and modern pharmacological research of Eucommia ulmoides Oliv

As a Traditional Chinese Medicine, Eucommia ulmoides Oliv. has been used for the treatment of various diseases since ancient times, involving lumbar pain, knee pain, osteoporosis, hepatoprotection, paralysis, intestinal haemorrhoids, vaginal bleeding, abortion, spermatorrhoea, foot fungus, anti-aging etc. With the developing discovery of E. ulmoides extracts and its active components in various pharmacological activities, E. ulmoides has gained more and more attention. Up to now, E. ulmoides has been revealed to show remarkable therapeutic effects on hypertension, hyperglycemia, diabetes, obesity, osteoporosis, Parkinson's disease, Alzheimer's disease, sexual dysfunction. E. ulmoides has also been reported to possess antioxidant, anti-inflammatory, neuroprotective, anti-fatigue, anti-aging, anti-cancer and immunoregulation activities etc. Along these lines, this review summarizes the traditional application and modern pharmacological research of E. ulmoides, providing novel insights of E. ulmoides in the treatment of various diseases.

Genome-wide association study reveals the genes associated with the leaf inclusion contents in Chinese medical tree Eucommia ulmoides

Eucommia ulmoides is an economic tree that can biosynthesize secondary metabolites with pharmacological functions. Genetic basis of biosynthesis of these compounds is almost unknown. Therefore, genomic-wide association study was performed to exploit the genetic loci maybe involved in biosynthetic pathways of 5 leaf inclusions (aucubin, chlorogenic acid, gutta-percha, polyphenols, total flavonoids). It was shown that contents of the 5 leaf metabolites have a wide variation following normal distribution. A total of 2 013 102 single nucleotide polymorphism (SNP) markers were identified in a population containing 62 individual clones. Through genome-wide association study analysis, many SNP loci were identified perhaps associated with phenotypes of the leaf inclusions. Higher transcriptional levels of the candidate genes denoted by significant SNPs in leaves suggested they may be involved in biosynthesis of the leaf inclusions. These genetic loci provide with invaluable information for further studies on the gene functions in biosynthesis of the leaf inclusions and selective breeding of the plus trees.

Enhanced Healthspan in Caenorhabditis elegans Treated With Extracts From the Traditional Chinese Medicine Plants Cuscuta chinensis Lam. and Eucommia ulmoides Oliv

To uncover potential anti-aging capacities of Traditional Chinese Medicine (TCM), the nematode Caenorhabditis elegans was used to investigate the effects of Eucommia ulmoides and Cuscuta chinensis extracts, selected by screening seven TCM extracts, on different healthspan parameters. Nematodes exposed to E. ulmoides and C. chinensis extracts, starting at the young adult stage, exhibited prolonged lifespan and increased survival after heat stress as well as upon exposure to the pathogenic bacterium Photorhabdus luminescens, whereby the survival benefits were monitored after stress initiation at different adult stages. However, only C. chinensis had the ability to enhance physical fitness: the swimming behavior and the pharyngeal pumping rate of C. elegans were improved at day 7 and especially at day 12 of adulthood. Finally, monitoring the red fluorescence of aged worms revealed that only C. chinensis extracts caused suppression of intestinal autofluorescence, a known marker of aging. The results underline the different modes of action of the tested plants extracts. E. ulmoides improved specifically the physiological fitness by increasing the survival probability of C. elegans after stress, while C. chinensis seems to be an overall healthspan enhancer, reflected in the suppressed autofluorescence, with beneficial effects on physical as well as physiological fitness. The C. chinensis effects may be hormetic: this is supported by increased gene expression of hsp-16.1 and by trend, also of hsp-12.6.

Adsorption and desorption characteristics of polyphenols from Eucommia ulmoides Oliv. leaves with macroporous resin and its inhibitory effect on α-amylase and α-glucosidase

Background

Eucommia ulmoides Oliv. (EUO) was a traditional Chinese herb, its leaves were abundant in China, and polyphenol compounds were considered to be an important active ingredient in Eucommia ulmoides Oliv. leaves (EUOL). However, previous research mainly focused on compound identification and extraction process, there were few reported on the efficient enrichment process and biological activity evaluation of polyphenols in EUOL.

Methods

The adsorption and desorption characteristics of twelve different resins (HPD-100, HPD-300, HPD-600, D-3250, X-5, D-140, NKA-9, NKA-II, D-101, AB-8, S-8 and Polyamide) were investigated to develop an efficient method for the enrichment of polyphenol from EUOL, and the static adsorption, kinetics, isotherm and thermodynamics of the polyphenol from EUOL were analyzed. The eluted component was obtained through dynamic elution, and its main polyphenol compounds were detected by high-phase liquid chromatography (HPLC) and the inhibitory effects on the enzyme activity of α-amylase and α-glucosidase was also evaluated for different elution components. Meanwhile, the binding of main polyphenol compounds to enzyme was also evaluated.

Results

The selected resins (HPD-300, HPD-600, D-3250, X-5, D-140, NKA-9, D-101 and AB-8) showed adsorption patterns that fitted well to the pseudo second-order kinetics. The intra-particle diffusion model demonstrated that the diffusion of polyphenol compounds on these resins were divided into three processes. For HPD-300, HPD-600 and NKA-9, the Freundlich model better described the adsorption isotherm behavior than the Langmuir model, and the adsorption of polyphenol was a physical, exothermic, and spontaneous process. Subsequently, dynamic elution was performed yielding a higher polyphenol content in a 60% ethanol-water elution component, and it also exhibited a higher inhibitory effect on α-amylase and α-glucosidase activity. Furthermore, as the main polyphenol compounds, chlorogenic acid, rutin, quercetin and kaempferol were used to simulate the binding to the enzyme protein through molecular docking technology. The results showed that quercetin had a higher docking score for α-amylase, while rutin displayed superior binding to α-glucosidase.

Conclusions

Therefore, polyphenols of EUOL could be enriched through macroporous resins and have the potential to be effective enzyme inhibitor.

Ethnobotany, Phytochemistry and Pharmacological Properties of Eucommia ulmoides: A Review

Eucommia ulmoides Oliver, a single species of Eucommia genus belonging to the Eucommiaceae family, is an endemic in China and has been used in traditional Chinese medicine for nearly two thousand years. Records from different historical periods highlight E. ulmoides and its officinal botanical parts, usefulness in adaptation to disease and its central role in Chinese medicine theory. There are also historical collection documents for minorities in China. Tearing the leaves, bark and fruit produces strands of latex; a description of E. ulmoides’s morphological features is recorded in this paper. This review summarizes 204 natural compounds isolated from this plant, which are divided into seven categories: lignans, iridoids, flavonoids, phenols, steroids, terpenes and others. These components possess wide-ranging pharmacological efficacies, such as antihypertensive, antihyperglycemic, antihyperlipidemia, anti-oxidative, anti-osteoporosis, antitumor, immunomodulatory and neuroprotective activities. This review aims to provide a reference for extensive researches of E. ulmoides crude drugs, especially for quality control, biosynthesis and structure modification of active ingredients and pharmacological mechanism.

Chlorogenic Acid Targeting of the AKT PH Domain Activates AKT/GSK3β/FOXO1 Signaling and Improves Glucose Metabolism

Chlorogenic acid (CGA), a bioactive component in the human diet, is reported to exert beneficial effects on the regulation of glucose metabolism. This study was designed to investigate the specific target of CGA, and explore its underlying mechanisms. Beneficial effects of CGA in glucose metabolism were confirmed in insulin-treated human hepatocarcinoma HepG2 cells. Protein fishing, via CGA-modified functionalized magnetic microspheres, demonstrated the binding of CGA with protein kinase B (AKT). Immunofluorescence using a CGA molecular probe further demonstrated the co-localization of CGA with AKT. A competitive combination test and hampering of AKT membrane translocation showed that CGA might bind to the pleckstrin homology (PH) domain of AKT. The specific binding did not lead to the membrane translocation to phosphatidylinositol (3,4,5)-trisphosphate (PIP₃), but directly activated the phosphorylation of AKT on Ser-473, induced the phosphorylation of the downstream molecules, glycogen synthase kinase 3β (GSK3β) and forkhead box O1 (FOXO1), and improved glucose metabolism. Collectively, our data demonstrate that CGA exerts regulatory effects on glucose metabolism via direct targeting the PH domain of AKT. This study clarifies the mechanism of the potential benefits of nutrients containing CGA in the complementary therapy of glucose metabolism disorders.

Eucommia ulmoides Oliver: A Potential Feedstock for Bioactive Products

Eucommia ulmoides Oliver (EUO), a traditional Chinese herb, contains a variety of bioactive chemicals, including lignans, iridoids, phenolics, steroids, terpenoids, flavonoids, etc. These bioactive chemicals possess the effective function in nourishing the liver and kidneys and regulating blood pressure. The composition of bioactive chemicals extracted from EUO vary in the different functional parts (leaves, seeds, bark, and staminate flower) and planting models. The bioactive parts of EUO are widely used as raw materials for medicine and food, powdery extracts, herbal formulations, and tinctures. These capabilities hold potential for future development and commercial exploitation of the bioactive products from EUO.

Optimized microwave extraction, characterization and antioxidant capacity of biological polysaccharides from Eucommia ulmoides Oliver leaf

Microwave-induced technique was combined with response surface methodology for optimizing the isolation of polysaccharides from Eucommia ulmoides Oliver leaf. The maximum polysaccharides yield of 12.31% was achieved by microwave extraction at 74 °C for 15 min with a solid to liquid ratio of 1:29 g/mL, which agreed with the predicted value and was 2.9-fold higher than that of the conventional heat-reflux extraction method. The dominant bioactive constituent in extracts was chlorogenic acid (1.3-1.9%), followed by geniposidic acid (1.0-1.7%). The polysaccharides from the optimized extraction had a high molecular weight and polydispersity (Mw 38,830 g/mol, Mw/Mn 2.19), as compared to the fraction prepared in the absence of microwave (Mw 12,055 g/mol, Mw/Mn 1.26). Glucose was the dominant sugar component (38.2-39.1%) of heterogeneous polysaccharides which belonged to a structure of β-type acidic heteropolysaccharides with a glucan group and highly branched degree. The polysaccharides showed a higher DPPH radical scavenging index (0.87-1.22) than BHT (0.41) but lower than BHA (3.56), which can act as a favorable antioxidant in functional food.

Efficient Discovery of Quality Control Markers for Gastrodia elata Tuber by Fingerprint-Efficacy Relationship Modelling

INTRODUCTION

Gastrodia elata tuber (GET) has been widely used in China as a famous herbal medicine. However, the quality control markers (QCMs) for GET still need further investigation.

OBJECTIVE

To develop a rational strategy based on fingerprint-efficacy relationship modelling to discover the efficacy-related QCMs, using GET as a case study.

METHODOLOGY

The high-performance liquid chromatography (HPLC) fingerprints of 13 batches of GET extracts were established and 10 common peaks were structurally characterised by HPLC coupled with quadrupole time-of-flight mass spectrometry (QTOF-MS). The neuroprotective effects of GET samples were evaluated using the in vitro model of β-amyloid peptide (Aβ_25-35 )-induced PC12 cell death. The fingerprint-efficacy relationship of chemical fingerprints and neuroprotective effects was linked by orthogonal projection to latent structure-discriminant analysis (OPLS-DA) model.

RESULTS

The chemical combination of 5-hydroxymethyl-2-furaldehyde (5-HMF), parishin B (PB) and parishin C (PC) was discovered and confirmed as QCMs of GET by the OPLS-DA method. The selected QCMs allowed to evaluate the relative quality of GET samples.

CONCLUSION

This study has demonstrated that the rational strategy based on fingerprint-efficacy relationship modelling might be generally applicable for the quality control of herbal medicines. Copyright © 2017 John Wiley & Sons, Ltd.

The Protective Effect of Aucubin from Eucommia ulmoides Against Status Epilepticus by Inducing Autophagy and Inhibiting Necroptosis

Eucommia ulmoides Oliv. is a famous traditional Chinese medicine which exhibits anti-oxidative stress ability and neuro-protective effects. Aucubin is the predominant component of Eucommia ulmoides Oliv. Our present study is intended to investigate aucubin's potential protective effects on neurons against epilepsy in the hippocampus by establishing the lithium-pilocarpine induced status epilepticus (SE) rat model in vivo. Aucubin (at a low dose and a high dose of 5[Formula: see text]mg/kg and 10[Formula: see text]mg/kg, respectively) was administered through gavage for two weeks before lithium-pilocarpine injection. Rats were sacrificed at 4, 24 and 72[Formula: see text]h after SE induction. Pretreatment with both low-dose and high-dose aucubin significantly reduced the number of death neurons ([Formula: see text]) and increased the number of surviving neurons ([Formula: see text]) in DG, Hilus, CA1 and CA3 hippocampal regions post SE. Meanwhile, it significantly inhibited necroptosis proteins (MLKL and RIP-1) ([Formula: see text] or [Formula: see text]) and enhanced autophagy protein (Beclin-1 and LC3BII/LC3BI) prevalence in the hippocampus ([Formula: see text] or [Formula: see text]). In conclusion, aucubin appeared to ameliorate damages in lithium-pilocarpine induced SE in hippocampus, reduce the number of apoptotic neurons, and increased the number of survival neurons by inducing autophagy and inhibiting necroptosis. These original findings might provide an important basis for the further investigation of the therapeutic role of aucubin in treatment or prevention of epilepsy-related neuronal damages.

A UPLC-MS Method for Simultaneous Determination of Geniposidic Acid, Two Lignans and Phenolics in Rat Plasma and its Application to Pharmacokinetic Studies of Eucommia ulmoides Extract in Rats

The bark of Eucommia ulmoides is a well-known Chinese herbal medicine that is used to regulate blood pressure and reduce blood sugar and fats, as well as an antioxidant and antimicrobial agent. Here we describe the development of a sensitive ultrahigh performance liquid chromatography-tandem mass spectrum method for the simultaneous determination of five major active ingredients of E. ulmoides bark extract, namely, geniposidic acid (GA), protocatechuic acid (PCA), chlorogenic acid (CA), (+)-pinoresinol di-O-β-D-glucopyranoside (PDG) and (+)-pinoresinol 4'-O-β-D-glucopyranoside (PG), in rat plasma. The preliminary steps in the plasma analysis were the addition of an internal standard and acidification (0.1 % formic acid), followed by protein precipitation with methanol. Separation of the active ingredients was performed on an ACQUITY UPLC® BEH C18 column (2.1 × 50 mm; internal diameter 1.7 µm) at a flow rate of 0.35 mL/min, with acetonitrile/water containing 0.1 % formic acid as the mobile phase. Detection was performed on a triple quadrupole tandem mass spectrometer via electrospray ionization source with positive and negative ionization modes. All calibration curves showed good linearity (r ≥ 0.997) over the concentration range with the low limit of quantification between 4.45 and 54.9 ng/mL. Precision was evaluated by intra- and inter-day assays, and the percentages of the relative standard deviation were all within 15 %. Extraction efficiency and matrix effect were 84.3-102.4 % and 98.1-112.2 %, respectively. The validated method was successfully applied to the pharmacokinetic study in rats after oral administration of E. ulmoides extract. The results indicate that the pharmacokinetic properties of GA differ from those of PCA, CA, PDG and PG, respectively.

Chinese herbal medicines promote hippocampal neuroproliferation, reduce stress hormone levels, inhibit apoptosis, and improve behavior in chronically stressed mice

ETHNOPHARMACOLOGICAL RELEVANCE

An efficacious antidepressant without unwanted side effects is need urgently at present. This study aimed to investigate whether treatment with four Chinese herbal medicines (CHMs), namely Radix Astragali, Saposhnikovia divaricate (SD), Eucommia ulmoides Oliv. bark (EU), and Corydalis yanhusuo W. T. Wang (C. yanhusuo), could reverse the effects of chronic mild stress (CMS) in a depression-like mouse model and the potential mechanism(s) of their action.

MATERIALS AND METHODS

In vitro study, the proliferation of NSCs was assessed using the MTS assay. In vivo study, chronic mild stress (CMS) was used in mice for 14 days to establish a depression-like mouse model. Plasma corticosterone levels were assessed by UPLC coupled to a triple-quadrupole mass spectrometer. The forced swim test (FST) was used to assess the effects of the four CHMs on depression. BrdU incorporation and TUNEL staining were used to assay hippocampal precursor cell proliferation rate and apoptosis.

RESULTS

The CHMs included Radix Astragali, EU, C. yanhusuo, and SD were shown to promote neuroproliferation in vitro. In vivo study, oral administration of these four CHMs for 14 days reversed the elevated plasma corticosterone levels, body weight loss, decrease in proliferation of hippocampal precursor cells; they also inhibited hippocampal cell apoptosis, and exhibited an antidepressant-like effect in a depression-like mouse model induced by CMS.

CONCLUSIONS

Our study indicates that each of these CHMs has the potential to ameliorate depression. The possible mechanisms of action include modulation of the HPA axis, reduction in stress hormone levels, inhibition of apoptosis, and promotion of hippocampal neuronal plasticity and neurogenesis.

Health-Promoting Properties of Eucommia ulmoides: A Review

Eucommia ulmoides (EU) (also known as “Du Zhong” in Chinese language) is a plant containing various kinds of chemical constituents such as lignans, iridoids, phenolics, steroids, flavonoids, and other compounds. These constituents of EU possess various medicinal properties and have been used in Chinese Traditional Medicine (TCM) as a folk drink and functional food for several thousand years. EU has several pharmacological properties such as antioxidant, anti-inflammatory, antiallergic, antimicrobial, anticancer, antiaging, cardioprotective, and neuroprotective properties. Hence, it has been widely used solely or in combination with other compounds to treat cardiovascular and cerebrovascular diseases, sexual dysfunction, cancer, metabolic syndrome, and neurological diseases. This review paper summarizes the various active ingredients contained in EU and their health-promoting properties, thus serving as a reference material for the application of EU.

Enzymatic Hydrolysis and Simultaneous Extraction for Preparation of Genipin from Bark of Eucommia ulmoides after Ultrasound, Microwave Pretreatment

A continuous process based on the combination of ultrasounds and/or microwaves pretreatments followed by enzymatic hydrolysis and simultaneous extraction (EHSE) has been proposed to recover genipin from Eucommia ulmoides bark. At first, in the pretreatment step, the mixture of 1.0 g dried bark powder and 10 mL deionized water were irradiated by microwave under 500 W for 10 min. Then, in hydrolysis step, the optimal conditions were as follows: 0.5 mg/mL of cellulase concentration, 4.0 pH of enzyme solution, 24 h of incubation time and 40 °C of incubation temperature. After incubation, 10 mL ethanol was added to extract genipin for 30 min by ultrasound. After EHSE treatment, the yield of genipin could reach 1.71 μmol/g. Moreover, scanning electron micrographs illustrated that severe structural disruption of plant was obtained by EHSE. The results indicated that the EHSE method provided a good alternative for the preparation of genipin from Eucommia ulmoides bark as well as other herbs.

UPLC-MS/MS determination and gender-related pharmacokinetic study of five active ingredients in rat plasma after oral administration of Eucommia cortex extract

ETHNOPHARMACOLOGICAL RELEVANCE

Eucommiae cortex (EC), the bark of Eucommia ulmoides Oliv., has been traditionally used to treat many diseases in China for more than 2000 years. The pharmacological effects are primarily attributed to the presence of lignans, iridoids and phenolics, which are main active ingredients in EC.

AIM OF THE STUDY

First, to investigate the active ingredients that can be absorbed into the rat plasma according to which ingredients exhibit significant correlation of drug concentration-time curve. Second, to establish an efficient ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) method for simultaneous determination of ingredients absorbed in rat plasma. Finally, to investigate gender effect on the pharmacokinetics of the ingredients absorbed in male and female rats plasma after oral administration with EC extract.

MATERIALS AND METHODS

18 ingredients from EC were detected by UPLC-MS/MS, 9 out of 18 ingredients were absorbed into rat plasma. And 5 ingredients exhibit significant correlation of drug concentration-time curve. They were pinoresinol di-O-β-d-glucopyranoside (PDG), geniposide (GE), geniposidic acid (GA), aucubin (AN) and chlorogenic acid (CA). The analytes were extracted from rat plasma via a simple protein precipitation procedure and osalmid was used as the internal standard. Chromatographic separation was achieved on a Waters ACQUITY HSS T3 column (2.1mm×100mm, 1.8μm) using a gradient elution program with acetonitrile and 0.1% formic acid water as the mobile phase, with a flow rate of 0.3mLmin(-1). The detection was performed on a triple-quadrupole tandem mass spectrometer by multiple reactions monitoring (MRM) mode in a positive ion mode via electrospray ionization (ESI). The transition monitored were /z 683.00[M+H](+)→235.10 for PDG, / z 389.00[M+H](+)→208.80 for GE, m/z 375.00[M+H](+)→194.79 for GA, m/z 364.00[M+NH4](+)→148.81 for AN, m/z 355.10[M+H](+)→162.84 for CA and m/z 230.03[M+H](+)→120.77 for internal standard.

RESULTS

The developed method showed good linearity over a wide concentration range, the lower limits of quantification and higher accuracy and precision for determination of the 5 analytes. Then the method was applied to study the pharmacokinetics in rats, and the results indicated that there were significant differences in pharmacokinetic parameters of the analytes between the male and female rats, and absorptions of these analytes in male group were all significantly higher than those in female group.

CONCLUSION

This study established an efficient, sensitive and selective UPLC-MS/MS method for simultaneous determination of the five ingredients in rat plasma, and it could be successfully applied to the comparative pharmacokinetic studies in male and female rats after oral administration with EC extract.

Neuroprotective effects of Eucommia ulmoides Oliv. and its bioactive constituent work via ameliorating the ubiquitin-proteasome system

BACKGROUND

Parkinson's disease (PD) is a chronic neurodegenerative disorder characterized by a loss of dopaminergic neurons in the substantia nigra, decreased striatal dopamine levels, and consequent extrapyramidal motor dysfunction. The purpose of this study was to investigate potential in vivo protective effects of Duzhong against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), as well as the bioactive constituents against 1-methyl-4-phenylpyridinium (MPP(+)) toxicity in vitro.

METHODS

Male C57BL/6 mice were intraperitoneally administrated five consecutive injections of MPTP every 24 h at a dose of 30 mg/kg to induce an in vivo PD model. Pole and traction tests were performed in mice to evaluate motor deficits and bradykinesia after the final MPTP administration. The striatal levels of dopamine and its metabolites, 3,4-dihydroxyphenylacetic acid and homovanilic acid, were measured using a High-performance liquid chromatography-electrical conductivity detector. To further explore the bioactive constituents and protective mechanisms of Duzhong, seven compounds from Duzhong were tested on MPP(+)-treated SH-SY5Y cell lines in vitro. A proteasome enzymatic assay and Cell Counting Kit-8 were performed to examine proteasomal activity and cell viability of Duzhong-treated cells, respectively, after exposure to MPP(+) and proteasome inhibitor MG132.

RESULTS

Duzhong antagonized the loss of striatal neurotransmitters and relieved the associated anomaly in ambulatory locomotor activity in PD mice after a 3-day pre-treatment of Duzhong crude extract. The five Duzhong compounds attenuated MPP(+)-induced dysfunction of protease activity and reduced MG132-induced cytotoxicity.

CONCLUSION

Duzhong could serve as a potential candidate for PD treatment, and its mechanism involves the amelioration of the ubiquitin-proteasome system.

Recent Progress of Research on Herbal Products Used in Traditional Chinese Medicine: the Herbs belonging to The Divine Husbandman's Herbal Foundation Canon ( Shén Nóng Běn Cǎo Jīng)

This article will review selected herbal products from Chinese Materia Medica that are used in Traditional Chinese Medicine. The herbs come from the upper, middle, and lower class medicines as listed in The Divine Husbandman's Herbal Foundation Canon (神農本草經 Shén Nóng Běn Cǎo Jīng). The review will focus on the active constituents of the herbs and their bioactivities, with emphasis on the most recent progress in research for the period of 2003 to 2011.

Eucommia ulmoides Oliv. bark. attenuates 6-hydroxydopamine-induced neuronal cell death through inhibition of oxidative stress in SH-SY5Y cells

ETHNOPHARMACOLOGICAL RELEVANCE

Eucommia ulmoides Oliv. Bark. (EUE) has commonly been used to fortify the muscles and lungs, lower blood pressure, prevent miscarriage, improve liver and kidney tone, and promote longevity as a traditional tonic medicine in Korea, China, and Japan.

AIM OF THE STUDY

In this study, we investigated the mechanisms by which EUE protects neuronal cells from apoptosis induced by the Parkinson's disease (PD)-related neurotoxin, 6-hydroxydopamine (6-OHDA).

MATERIALS AND METHODS

We determined the neuroprotective effects of EUE on 6-OHDA-induced neuronal cell death, cytotoxicity, reactive oxygen species (ROS) production, and mitochondrial membrane dysfunction. Moreover, we examined whether EUE suppressed phosphorylation of c-Jun N-terminal kinase (JNK), phosphatidylinositol 3-kinase (PI3K)/Akt, and glycogen synthase kinase-3 beta (GSK-3β). Furthermore, the neuroprotective effects of EUE on 6-OHDA-induced activation of nuclear factor-kappa B (NF-κB) was studied in SH-SY5Y cells.

RESULTS

Pretreatment of SH-SY5Y cells with EUE significantly reduced 6-OHDA-induced cell death and cytotoxicity. EUE inhibited 6-OHDA-induced generation of ROS, which conferred cytoprotection against 6-OHDA-induced oxidative injury. EUE treatment also strikingly inhibited 6-OHDA-induced mitochondrial dysfunction. In addition, EUE suppressed phosphorylation of JNK, PI3K/Akt, and GSK-3β. Furthermore, EUE blocked 6-OHDA-induced NF-κB nuclear translocation, an event downstream from JNK, PI3K/Akt, and GSK-3β phosphorylation. Moreover, chlorogenic acid (CGA), one of the active constituents of EUE, was also able to reduce 6-OHDA-induced toxicity in SH-SY5Y cells.

CONCLUSION

Taken together, these results suggest that EUE attenuates oxidative stress through activation of JNK, PI3K/Akt, GSK-3β, and NF-κB pathways, thereby protecting cells from neuronal cell death.

Eucommia ulmoides Oliv.: ethnopharmacology, phytochemistry and pharmacology of an important traditional Chinese medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Eucommia ulmoides Oliv. (Family Eucommiaceae), also known as Dù-zhòng (Chinese: ), Tuchong (in Japanese), is the sole species of the genus Eucommia. The leaf, stem, and bark as well as staminate flower of Eucommia ulmoides have been traditionally used to cure many diseases in China, Japan, Korea, among others. The aim of this review is to comprehensively outline the botanical description, ethnopharmacology, phytochemistry, biological activities, and toxicology of Eucommia ulmoides and to discuss possible trends for further study of Eucommia ulmoides.

MATERIALS AND METHODS

Information on Eucommia ulmoides was gathered via the internet (using Pub Med, Elsevier, Baidu Scholar, Google Scholar, Medline Plus, ACS, CNKI, and Web of Science) and from books in local libraries.

RESULTS

One-hundred twelve compounds of Eucommia ulmoides, including the main active constituents, lignans and iridoids, have been isolated and identified. In vitro and in vivo studies indicated that monomer compounds and extracts from Eucommia ulmoides possess wide-ranging pharmacological actions, especially in treating hypertension, hyperlipemia, diabetes, obesity, sexual dysfunction, osteoporosis, Alzheimer's disease, aging, lupus-like syndrome, and immunoregulation.

CONCLUSIONS

Eucommia ulmoides has been used as a source of traditional medicine and as a beneficial health food. Phytochemical and pharmacological studies of Eucommia ulmoides have received much interest, and extracts and active compounds continue to be isolated and proven to exert various effects. Further toxicity and clinical studies are warranted to establish more detailed data on crude extracts and pure compounds, enabling more convenient preparations for patients. Therefore, this review on the ethnopharmacology, phytochemistry, biological activities, and toxicity of Eucommia ulmoides will provide helpful data for further studies as well as the commercial exploitation of this traditional medicine.

Geniposidic acid protects against D-galactosamine and lipopolysaccharide-induced hepatic failure in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Geniposidic acid (GA) is an iridoid glucoside isolated from Gardeniae jasminoides Ellis (Rubiaceae) that has long been used to treat inflammation, jaundice and hepatic disorders.

AIMS OF THE STUDY

This study examined the cytoprotective properties of GA against D-galactosamine (GalN)/lipopolysaccharide (LPS)-induced fulminant hepatic failure.

MATERIALS AND METHODS

Mice were given an intraperitoneal injection of GA (12.5, 25, 50 mg/kg) 1h before receiving GalN (800 mg/kg)/LPS (40 μg/kg). Liver and blood samples were collected 1 and 8 h after GalN/LPS injection.

RESULTS

The survival rate of the GA group was significantly higher than the control. GalN/LPS increased serum aminotransferase activity, serum tumor necrosis factor-α level and hepatic lipid peroxidation and decreased hepatic glutathione content. These changes were attenuated by GA. GA augmented increases in serum interleukin-6 level, heme oxygenase-1 and NF-E2-related factor 2 protein expression. Mice treated with GA decreased cleaved caspase-8 and caspase-3 protein expression and showed significantly fewer apoptotic cells. GA increased Bcl-xL protein expression and decreased Bax protein expression. Moreover, GA treatment enhanced phosphorylation of signal transducer and activator of transcription 3.

CONCLUSION

Our findings suggest that geniposidic acid alleviates GalN/LPS-induced liver injury by enhancing antioxidative defense system and reducing apoptotic signaling pathways.

Validation of a HPLC-tandem MS/MS method for pharmacokinetics study of (+)-pinoresinol-di-β-D-glucopyranoside from Eucommia ulmoides Oliv extract in rats' plasma

Natural plant compounds have an unexceptional influence in pharmacy as they provide an uncountable number of invaluable lead molecules. Phytochemical researches nowadays focus on bio-assay guided revealing of the therapeutic profile and synergism of medicinal herbs and their constituents. Assessing the clinical and biological potential and determining the pharmacokinetics of herbal constituents is also an area of much interest. This work was conducted in order to carry out a sensitive liquid chromatography tandem mass spectrum (HPLC-MS/MS) method for the pharmacokinetics study of (+)-pinoresinol-di-β-D-glucopyranoside (PG) in rats' plasma after oral administration of Eucommia ulmoides Oliv extract. The validated method was by means of linearity, precision, matrix effect and recovery so that it could be used for the pharmacokinetic study of PG. The obtained pharmacokinetic parameters shown that PG pertains to one-compartment model and 95% of PG was eliminated within 12h.

Antioxidant properties of Du-zhong (Eucommia ulmoides Oliv.) extracts and their effects on color stability and lipid oxidation of raw pork patties

The ethanol extracts from leaf, roasted cortex, and seed of Du-zhong ( Eucommia ulmoides Oliv.) were examined for total phenolics content (TPC) and total flavonoids content (TFC). The antioxidant activity of the extracts was evaluated by measuring the radical scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and lipid peroxidation inhibition capacity in a beta-carotene/linoleic acid system. Du-zhong leaf extract was found to have the highest TPC content (94.46 +/- 1.17 mg of gallic acid equiv/g of solid extract) and TFC content (61.36 +/- 0.59 mg of catechin equiv/g of solid extract). In the above three antioxidant assay systems, Du-zhong leaf extract also exhibited the strongest antioxidant capacities, followed by roasted cortex extract and seed extract. The effects of Du-zhong extracts (leaf, roasted cortex, and seed) on lipid oxidation, meat color, and metmyoglobin (MetMb) formation in raw pork patties were investigated and compared with that of butylated hydroxytoluene (BHT) during refrigerated storage at 4 degrees C for 8 days. The results indicated that the addition of leaf extract at 0.1% (w/w), roasted cortex extract at 0.1% (w/w), and BHT at 0.01% (w/w) decreased day 8 TBARS values by 35, 20, and 37%, respectively. Du-zhong leaf extract at 0.1% (w/w) also exhibited a certain stabilizing effect on meat redness a* value and retarded the formation of MetMb. This study suggests that Du-zhong leaf extract may be a potential source of natural antioxidants.