Parishin C's prevention of Aβ 1-42-induced inhibition of long-term potentiation is related to NMDA receptors

Sleep promoting and omics exploration on probiotics fermented Gastrodia elata Blume

Fermenting Chinese medicinal herbs could enhance their bioactivities. We hypothesized probiotic-fermented gastrodia elata Blume (GE) with better potential to alleviate insomnia than that of unfermented, thus the changes in chemical composition and the insomnia-alleviating effects and mechanisms of fermented GE on pentylenetetrazole (PTZ)-induced insomnia zebrafish were explored via high-performance liquid chromatography (HPLC) and mass spectroscopy-coupled HPLC (HPLC-MS), phenotypic, transcriptomic, and metabolomics analysis. The results demonstrated that probiotic fermented GE performed better than unfermented GE in increasing the content of chemical composition, reducing the displacement, average speed, and number of apoptotic cells in zebrafish with insomnia. Metabolomic investigation showed that the anti-insomnia effect was related to regulating the pathways of actin cytoskeleton and neuroactive ligand-receptor interactions. Transcriptomic and reverse transcription qPCR (RT-qPCR) analysis revealed that secondary fermentation liquid (SFL) significantly modulated the expression levels of neurod1, msh2, msh3, recql4, ercc5, rad5lc, and rev3l, which are mainly involved in neuron differentiation and DNA repair. Collectively, as a functional food, fermented GE possessed potential for insomnia alleviation.

Identification of key anti-neuroinflammatory components in Gastrodiae Rhizoma based on spectrum-effect relationships and its mechanism exploration

Gastrodiae Rhizoma was proven to have anti-inflammatory activity based on its main component of 4-hydroxybenzyl alcohol (4-HBA) and gastrodin (GAS). However, the anti-inflammatory activity of other phenols has been less reported. In this study, the n-BuOH extract was selected as the active anti-inflammatory part of Gastrodiae Rhizoma based on the LPS-induced inflammatory BV-2 cells. The spectral-effect relationship analysis of the n-BuOH extract showed the main effective components were GAS, 4-HBA, parishin A (PA), parishin B (PB), and parishin C (PC). Among them, PB could reduce LPS-induced expression of nitric oxide (NO), intracellular ROS, TNF-α, IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). Molecular docking predicted that PB had a good binding capacity to AMPKα and SIRT1 proteins of -12.1 kJ/mol and -7.6 kJ/mol, respectively. The Western Blot results further demonstrated that PB could inhibit NF-κB pathway by activating AMPK/SIRT1 pathway, thus exerting anti-LPS-induced neuroinflammatory effects. This study provides a referable idea for solving the problem of unclear action of TCM with complex compositions and is of great significance for the development of innovative medicines of traditional Chinese medicine.

Antidepressant effects of Parishin C in chronic social defeat stress-induced depressive mice

ETHNOPHARMACOLOGY RELEVANCE

Parishin C (Par), a prominent bioactive compound in Gastrodia elata Blume with little toxicity and shown neuroprotective effects. However, its impact on depression remains largely unexplored.

AIM OF THE STUDY

This study aims to investigate the antidepressant effects of Par using a chronic social defeat stress (CSDS) mouse model and elucidate its molecular mechanisms.

MATERIALS AND METHODS

The CSDS-induced depression mouse model was used to evaluate the therapeutic efficacy of Par. The social interaction test (SIT) and sucrose preference test (SPT), tail suspension test (TST) and forced swim test (FST) were conducted to assess the effects of Par on depressive-like behaviours. The levels of corticosterone, neurotransmitters (5-HT, DA and NE) and inflammatory cytokines (IL-1β, TNF-α, and IL-6) were evaluated by enzyme-linked immunosorbent assay (ELISA). Activation of a microglia was assessed by immunofluorescence labeling Iba-1. The protein expressions of NLRP3, ASC, caspase-1, and IL-6 verified by Western blot.

RESULT

Oral administration of Par (4 and 8 mg/kg) and fluoxetine (10 mg/kg, administration significantly ameliorate depression-like behaviors induced by CSDS, as shown by the increase social interaction in SIT, increase sucrose preference in SPT and the decrease immobility in TST and FST. Par administration decreased serum corticosterone level and increased the 5-HT, DA and NE concentration in the hippocampus and prefrontal cortex. Furthermore, Par treatment suppressed microglial activation (Iba1) as well as reduced levels of IL-1β, TNF-α, and IL-6) with decreased protein expressions of NLRP3, ASC, caspase-1, and IL-6.

CONCLUSIONS

our study provides the first evidence that Par exerts antidepressant-like effects in mice with CSDS-induced depression. This effect appears to be mediated by the normalization of neurotransmitter and corticosterone levels, inhibition of NLRP3 inflammasome activation. This newfound antidepressant property of Par offers a novel perspective on its pharmacological effects, providing valuable insights into its potential therapeutic and preventive applications in depression treatment.

Specific gut microbiome and metabolome changes in patients with continuous ambulatory peritoneal dialysis and comparison between patients with different dialysis vintages

Background

In recent years, the role of gut microbiota and derived metabolites in renal disease has attracted more attention. It has been established that the gut microbiota is a potential target for medical interventions in renal disease including chronic kidney disease (CKD), acute kidney injury (AKI) and renal calculus. Emerging evidence has related dialysis treatment to the microbial composition and function of the intestines, and there are many reports related to HD, but few studies have been related to PD. Previous studies have found that PD patients have intestinal flora disturbances, so we speculate that intestinal flora and its metabolites may be the regulatory factors in long-term therapy of PD. And as far as we know, there have been no studies characterized the gut microbiota in PD patients of different dialysis vintages.

Methods

It is a cross-sectional study based on clinical data and biological samples of 72 patients with CAPD, 13 patients with ESRD and 13 healthy volunteers. The intestinal microecological characteristics of CAPD patients were comprehensively evaluated by combining the intestinal microflora structure, enterotoxin and receptor (serum LPS and LBP), intestinal barrier function index (serum D-Lactate), intestinal uremic toxin (serum IS, PCS, TMAO), fecal SCFAs and other multi-dimensional and multi-omics studies. Furthermore, the changes of intestinal microecology in CAPD patients of different dialysis vintages (≥ 3 and < 12 months, ≥ 12 and < 24 months, ≥ 24 and < 60 months, ≥ 60 months) were further explored, and the correlations between intestinal microecology indicators and some clinical indicators were analyzed. Fecal and serum samples were collected from PD patients (PD group, n = 72), ESRD patients (ESRD group, n = 13) and healthy volunteers (Normal group, n = 13). Fecal samples were subjected to microbiome (16S rDNA) and SCFA (GC-MS) analyses. Serum samples were subjected to LPS, LBP, D-lactate, IS, PCS, and TMAO (ELISA) analyses.

Results

The diversity and richness of intestinal flora in CAPD patients were lower than those in healthy people and ESRD patients, and the microflora structure was different. Anaerobes of Blautia and facultative anaerobes and aerobic bacteria with Bacilli and Lactobacillales those in Firmicutes are the main intestinal flora in CAPD patients. The abundance of Bacteroidaceae, Bacteroides, Faecalibacterium and other dominant bacteria in the intestinal tract of CAPD patients decreased. Proteobacteria, Enterobacteriaceae and Escherichia-Shigella increased their colonization (LDA > 4). In CAPD patients of different dialysis vintages, there was no significant change in the diversity and richness of microflora, and the microflora structure of PDC group was significantly different from that of PDD, which the abnormal expansion of enterobacter group was more prominent in PDC and the abundance of Bacteroides group was relatively higher in PDD. Intestinal barrier damage, intestinal uremic toxin accumulation and short-chain fatty acid reduction were observed in CAPD patients, such as the serum level of D-Lactate, PCS and TMAO were significantly higher than that in the Normal group (P < 0.05),and the fecal levels of BA and CA were significantly lower (P < 0.05). The intestinal microecological disorder of PDC group, while that of PDD group showed a better trend. Such as the PDC group had a significantly higher serum level of LPS, D-Lactate and TMAO (P < 0.01), and significantly lower serum level of LBP (P < 0.01), and lower fecal levels of AA and BA (P > 0.05) than the PDD group.

Conclusion

The intestinal microecology and metabolic system of CAPD patients had changes compared with healthy people and ESRD non-dialysis patients, and there were differences in CAPD patients with different dialysis vintages. PD patients on dialysis for more than 60 months showed a better trend in the intestinal microecology than patients with 24∼36 months, which suggested that the intestinal microecology of PD patients had a certain ability of self-regulation and remodeling under the management of standardized system and it is necessary to strengthen the monitoring of the intestinal status and the occurrence of related complications in PD patients on dialysis of 24∼36 months of dialysis vintage. It is initially considered that the mechanism of intestinal microecology is a potential target for intervention in the diagnosis and treatment of CAPD and incorporating intestinal microecosystem monitoring into the long-term management of CAPD patients is a new strategy.

The processing methods, phytochemistry and pharmacology of Gastrodia elata Bl.: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Gastrodia elata Bl. (GE) is one of the rare Chinese medicinal materials with a long history of medicine and cooking. It consists of a variety of chemical components, including aromatic compounds, organic acids and esters, steroids, saccharides and their glycosides, etc., which has medicinal and edible value, and is widely used in various diseases, such as infantile convulsions, epilepsy, tetanus, headache, dizziness, limb numbness, rheumatism and arthralgia. It is also commonly used in health care products and cosmetics. Thus, its chemical composition and pharmacological activity have attracted more and more attention from the scientific community.

AIM

In this review, the processing methods, phytochemistry and pharmacological activities of GE were comprehensively and systematically summarized, which provides a valuable reference for researchers the rational of GE.

MATERIALS AND METHODS

A comprehensive search of published literature and classic books from 1958 to 2023 was conducted using online bibliographic databases PubMed, Google Scholar, ACS, Science Direct Database, CNKI and others to identify original research related to GE, its processing methods, active ingredients and pharmacological activities.

RESULTS

GE is traditionally used to treat infantile convulsion, epilepsy, tetanus, headache, dizziness, limb numbness, rheumatism and arthralgia. To date, more than 435 chemical constituents were identified from GE including 276 chemical constituents, 72 volatile components and 87 synthetic compounds, which are the primary bioactive compounds. In addition, there are other biological components, such as organic acids and esters, steroids and adenosines. These extracts have nervous system and cardiovascular and cerebrovascular system activities such as sedative-hypnotic, anticonvulsant, antiepileptic, neuron protection and regeneration, analgesia, antidepressant, antihypertensive, antidiabetic, antiplatelet aggregation, anti-inflammatory, etc. CONCLUSION: This review summarizes the processing methods, chemical composition, pharmacological activities, and molecular mechanism of GE over the last 66 years, which provides a valuable reference for researchers to understand its research status and applications.

Parishin A-loaded mesoporous silica nanoparticles modulate macrophage polarization to attenuate tendinopathy

Macrophages are involved mainly in the balance between inflammation and tenogenesis during the healing process of tendinopathy. However, etiological therapeutic strategies to efficiently treat tendinopathy by modulating macrophage state are still lacking. In this study, we find that a small molecule compound Parishin-A (PA) isolated from Gastrodia elata could promote anti-inflammatory M2 macrophage polarization by inhibiting gene transcription and protein phosphorylation of signal transducers and activators of transcription 1. Local injection or sustained delivery of PA by mesoporous silica nanoparticles (MSNs) could almost recover the native tendon's dense parallel-aligned collagen matrix in collagenase-induced tendinopathy by modulating macrophage-mediated immune microenvironment and preventing heterotopic ossification. Especially, MSNs decrease doses of PA, frequency of injection and yield preferable therapeutic effects. Mechanistically, intervention with PA could indirectly inhibit activation of mammalian target of rapamycin to repress chondrogenic and osteogenic differentiation of tendon stem/progenitor cells by influencing macrophage inflammatory cytokine secretion. Together, pharmacological intervention with a natural small-molecule compound to modulate macrophage status appears to be a promising strategy for tendinopathy treatment.

pH as a Key Factor for the Quality Assurance of the Preparation of Gastrodiae Rhizoma Formula Granules

Gastrodiae rhizoma (GR) formula granules and preparations have been used as a popular traditional Chinese medicine for clinical treatment since they have good pharmacological activity to treat nervous system diseases. Gastrodin and parishins have been the main active components in aqueous extracts for GR formula granules, but their pharmacological activities and metabolism are different. For quality control of the extracts, the extraction conditions should be investigated to accurately control the contents of two kinds of components. In this paper, the transfer rate of six index components (including gastrodin, p-hydroxybenzyl alcohol, parishin A, parishin B, parishin C, and parishin E) obtained by HPLC were used as indicators to investigate the effect of pH on the GR extraction process. The results demonstrated that pH is a key factor for preventing transforming parishins into gastrodin and maintaining high content of parishins in the extracts. It can be concluded that the weak acid environment could improve the transfer rate of parishins, thus ensuring the gastrodin and parishins consistency between GR raw materials and its aqueous extracts. Therefore, pH is an essential condition for accurate quality control of the extracts.

Targeting redox-altered plasticity to reactivate synaptic function: A novel therapeutic strategy for cognitive disorder

Redox-altered plasticity refers to redox-dependent reversible changes in synaptic plasticity via altering functions of key proteins, such as N-methyl-d-aspartate receptor (NMDAR). Age-related cognitive disorders includes Alzheimer's disease (AD), vascular dementia (VD), and age-associated memory impairment (AAMI). Based on the critical role of NMDAR-dependent long-term potentiation (LTP) in memory, the increase of reactive oxygen species in cognitive disorders, and the sensitivity of NMDAR to the redox status, converging lines have suggested the redox-altered NMDAR-dependent plasticity might underlie the synaptic dysfunctions associated with cognitive disorders. In this review, we summarize the involvement of redox-altered plasticity in cognitive disorders by presenting the available evidence. According to reports from our laboratory and other groups, this "redox-altered plasticity" is more similar to functional changes rather than organic injuries, and strategies targeting redox-altered plasticity using pharmacological agents might reverse synaptic dysfunctions and memory abnormalities in the early stage of cognitive disorders. Targeting redox modifications for NMDARs may serve as a novel therapeutic strategy for memory deficits.

Insight into Medicinal Chemistry Behind Traditional Chinese Medicines: p-Hydroxybenzyl Alcohol-Derived Dimers and Trimers from Gastrodia elata

From an aqueous extract of "tian ma" (the steamed and dried rhizomes of Gastrodia elata), ten new compounds gastrodibenzins A-D (1-4) and gastrotribenzins A-F (5-10), along with known analogues (11-20), having structure features coupling between two and three p-hydroxybenzyl-derived units via carbon- and/or ether-bonds, were isolated and characterized by spectroscopic data analysis. Meanwhile, the new compounds 5a, 6a, 8a, 22, and 23, as well as the known derivatives 13a, 14a, 15, 17-21, 24, 25, and p-hydroxybenzyl aldehyde were isolated and identified from a refluxed aqueous solution of p-hydroxybenzyl alcohol. Methylation of 5a and 6a in methanol and ethylation of 6a, 8a, 13a, and 14a in ethanol produced 5 and 6 and 7, 8, 13, and 14, respectively. using ultra-performance liquid chromatography high-resolution electrospray ionization mass spectrometry (UPLC-HRESIMS) analysis of the refluxed solutions of p-hydroxybenzyl alcohol and the refluxed extracts of the fresh G. elata rhizome and "tian ma" extracts indicated consistent production and variation of the dimeric and trimeric derivatives of p-hydroxybenzyl alcohol upon extracting solvents and refluxing time. In various assays, the dimeric and trimeric derivatives showed more potent activities than p-hydroxybenzyl alcohol itself and gastrodin, which are the main known active constituents of "tian ma". These results revealed for the first time that the more effective dimers and trimers can be produced through condensation of the co-occurring p-hydroxybenzyl alcohol during processing and decocting of the G. elata rhizomes, demonstrating insights into medicinal chemistry behind application protocols of traditional Chinese medicines.

Ameliorative Effect of Parishin C Against Cerebral Ischemia-Induced Brain Tissue Injury by Reducing Oxidative Stress and Inflammatory Responses in Rat Model

BACKGROUND

Gastrodia elata Blume (Orchidaceae) is a widely used traditional Chinese herbal medicine in the clinical practice of China, to treat nervous headache, convulsions, dizziness, neurasthenia, and so on. Parishin C (Par C), one of the major bioactive components of Gastrodia elata Blume, is known to exert many different biological activities, including antipsychotic and neuroprotective effects. However, there is little research about its neuroprotective effect in an ischemic stroke model. The objective of the present study is thus to investigate the neuroprotective effects of Par C against cerebral ischemia damage.

METHODS

Rats were pretreated with Par C (25, 50, or 100 mg/kg/day, i.p.) for 21 days, then subjected to 2 h of middle cerebral artery occlusion (MCAO) and 22 h of reperfusion. Neurological deficient scores, brain water content, histopathology, TCC staining were performed to assess the neuroprotective effects of Par C. Meanwhile, the oxidative stress, inflammation and apoptosis-related markers of brain tissue were evaluated by corresponding assay kits. Besides, the antioxidant and pro-inflammatory expression was measured by real-time quantification PCR (RT-qPCR).

RESULTS

Our findings indicated that the pre-treatment with Par C improved nerve function, suppressed oxidative stress, and pro-inflammatory factors release in rats with cerebral ischemia damage. Besides, Par C significantly increased antioxidant expression and declined pro-inflammatory cytokines expression.

CONCLUSION

Par C is shown to exert neuroprotective effects partly via inhibiting oxidative stress and inflammation in a rat model of MCAO.

A simplified LC−MS/MS approach for simultaneous quantification and pharmacokinetics of five compounds in rats following oral administration of Gastrodia elata extract

Background

To support the multicomponent pharmacokinetics of Gastrodia elata, a rapid, simple, and sensitive ultra-performance liquid chromatography tandem with mass spectrometry (LC–MS/MS) approach was established for simultaneous quantification of gastrodin, parishin A, parishin B, parishin C, and parishin E.

Methods

Five compounds were extracted from plasma by using one-step protein precipitation. The chromatographic separation was achieved on a C18 column with gradient mobile phase comprising acetonitrile and 0.05% formic acid. The detection was performed using negative electrospray ionization in multiple reaction monitoring mode.

Results

This new method maximizes assay throughput by using minimal sample clean-up procedures and a shorter analytical run time. The approach exhibited good linearity for the five compounds (r2 > 0.995) in the concentration ranges. The lower limits of quantification (LLOQ) were determined as 1.37 ng/mL for parishin A, parishin B, parishin C, and parishin E and 10 ng/mL for gastrodin. Then the method was fully validated with intra- and inter-day precision, accuracy, matrix effects, extraction recovery, and stability.

Conclusion

This validated approach was successfully applied to the pharmacokinetic study following oral administration of Gastrodia elata extract to rats. This investigation may provide some guidance for the clinical application and explanation of the pharmacological mechanism of Gastrodia elata.

Indole alkaloid glycosides with a 1'-(phenyl)ethyl unit from Isatis indigotica leaves

Seven indole alkaloid glycosides containing a 1′-(4″-hydroxy-3″,5″-dimethoxyphenyl)ethyl unit (1–7) were isolated from an aqueous extract of Isatis indigotica leaves (da qing ye). Their structures were determined by spectroscopic data analysis combined with enzymatic hydrolysis as well as comparison of their experimental CD (circular dichroism) and calculated ECD (electrostatic circular dichroism) spectra. Based on analysis of [α]D20 and/or Cotton effect (CE) data of 1–7, two simple roles to assign location and/or configuration of β-glycopyranosyloxy and 1′-(phenyl)ethyl units in the indole alkaloid glycosides are proposed. Stereoselectivity in plausible biosynthetic pathways of 1–7 is discussed. Compounds 3 and 4 and their mixture in a 3:2 ratio showed activity against KCNQ2 in CHO cells. The mixture of 5 and 6 (3:2) exhibited antiviral activity against influenza virus H1N1 PR8 with IC₅₀ 64.7 μmol/L (ribavirin, IC₅₀ 54.3 μmol/L), however, the individual 5 or 6 was inactive. Preliminary structure–activity relationships were observed.

Metabolite Profiling and Distribution of Militarine in Rats Using UPLC-Q-TOF-MS/MS

Militarine, a natural glucosyloxybenzyl 2-isobutylmalate, isolated from Bletilla striata, was reported with a prominent neuroprotective effect recently. The limited information on the metabolism of militarine impedes comprehension of its biological actions and pharmacology. This study aimed to investigate the metabolite profile and the distribution of militarine in vivo, which help to clarify the action mechanism further. A total of 71 metabolites (57 new metabolites) in rats were identified with a systematic method by ultra-high-performance liquid chromatography combined with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS). The proposed metabolic pathways of militarine include hydrolyzation, oxidation, glycosylation, esterification, sulfation, glucuronidation and glycine conjugation. Militarine and its metabolites were distributed extensively in the treated rats. Notably, six metabolites of militarine were identified in cerebrospinal fluid (CSF), which were highly consistent with the metabolites after oral administration of gastrodin in rats. Among the metabolites in CSF, five of them were not reported before. It is the first systematic metabolic study of militarine in vivo, which is very helpful for better comprehension of the functions and the central nervous system (CNS) bioactivities of militarine. The findings will also provide an essential reference for the metabolism of other glucosylated benzyl esters of succinic, malic, tartaric and citric acids.

Transformation Mechanisms of Chemical Ingredients in Steaming Process of Gastrodia elata Blume

To explore the transformation mechanisms of free gastrodin and combined gastrodin before and after steaming of Gastrodia elata (G. elata), a fresh G. elata sample was processed by the traditional steaming method prescribed by Chinese Pharmacopoeia (2015 version), and HPLC-ESI-TOF/MS method was used to identify the chemical composition in steamed and fresh G. elata. Finally, 25 components were identified in G. elata based on the characteristic fragments of the compounds and the changes of the 25 components of fresh and steamed G. elata were compared by the relative content. Hydrolysis experiments and enzymatic hydrolysis experiments of 10 monomer compounds simulating the G. elata steaming process were carried out for the first time. As a result, hydrolysis experiments proved that free gastrodin or p-hydroxybenzyl alcohol could be obtained by breaking ester bond or ether bond during the steaming process of G. elata. Enzymatic experiments showed that steaming played an important role in the protection of gastrodin, confirming the hypothesis that steaming can promote the conversion of chemical constituents of G. elata—inhibiting enzymatic degradation. This experiment clarified the scientific mechanism of the traditional steaming method of G. elata and provided reference for how to apply G. elata decoction to some extent.

Optimal Extraction Study of Gastrodin-Type Components from Gastrodia Elata Tubers by Response Surface Design with Integrated Phytochemical and Bioactivity Evaluation

Gastrodia elata tuber (GET) is a popular traditional Chinese medicines (TCMs). In this study, response surface methodology (RSM) with a Box–Behnken design (BBD) was performed to optimize the extraction parameters of gastrodin-type components (gastrodin, gastrodigenin, parishin A, parishin B, parishin C and parishin E). Different from the conventional studies that merely focused on the contents of phytochemical, we gave consideration to both quantitative analysis of the above six components by HPLC and representative bioactivities of GET, including antioxidation and protection of human umbilical vein endothelial cells (HUVEC). Four independent variables (ethanol concentration, liquid-material ratio, soaking time and extraction time) were investigated with the integrated evaluation index of phytochemical contents. With the validation experiments, the optimal extraction parameters were as follows: ethanol concentration of 41%, liquid–solid ratio of 28.58 mL/g, soaking time of 23.91 h and extraction time of 46.60 min. Under the optimum conditions, the actual standardized comprehensive score was 1.8134 ± 0.0110, which was in accordance with the predicted score of 1.8100. This firstly established method was proved to be feasible and reliable to optimize the extraction parameters of the bioactive components from GET. Furthermore, it provides some reference for the quality control and extraction optimization of TCMs.

Effect of inorganic salt on partition of high-polarity parishins in two-phase solvent systems and separation by high-speed counter-current chromatography from Gastrodia elata Blume

Parishins are high-polarity and major bioactive constituents in Gastrodia elata Blume. In this study, the effect of several inorganic salts on the partition of parishins in two-phase solvent systems was investigated. Adding ammonium sulfate, which has a higher solubility in water, was found to significantly promote the partition of parishins in the upper organic polar solvents. Based on the results, a two-phase solvent system composed of butyl alcohol/acetonitrile/near-saturated ammonium sulfate solution/water (1.5:0.5:1.2:1, v/v/v/v) was used for the purification of parishins by high-speed counter-current chromatography. Fractions obtained from high-speed counter-current chromatography were subjected to semi-preparative high-performance liquid chromatography to remove salt and impurities. As a result, parishin E (6.0 mg), parishin B (7.8 mg), parishin C (3.2 mg), gastrodin (15.3 mg), and parishin A (7.3 mg) were isolated from water extract of Gastrodia elata Blume (400 mg). These results demonstrated that adding inorganic salt that has high solubility in water to the two-phase solvent system in high-speed counter-current chromatography was a suitable approach for the purification of high-polarity compounds.

Sulfur-enriched alkaloids from the root of Isatis indigotica

Five new sulfur-enriched alkaloids isatithioetherins A-E (1-5), and two pairs of scalemic enantiomers (+)- and (-)-isatithiopyrin B (6a and 6b) and isoepigoitrin and isogoitrin (7a and 7b), along with the known scalemic enantiomers epigoitrin and goitrin (8a and 8b), were isolated and characterized from an aqueous extract of the Isatis indigotica roots. Their structures were determined by extensive spectroscopic data analysis, including 2D NMR and theoretical calculations of electronic circular dichroism (ECD) spectra based on the quantum-mechanical time-dependent density functional theory (TDDFT). Compounds 1-5 represent a novel group of sulfur-enriched alkaloids, biogenetically originating from stereoselective assemblies of epigoitrin-derived units. Isolation and structure characterization of 6a and 6b support the postulated biosynthetic pathways for the diastereomers 9a and 9b via a rare thio-Diels-Alder reaction. Compounds 2 and 4 showed antiviral activity against the influenza virus A/Hanfang/359/95 (H3N2, IC50 0.60 and 1.92 μmol/L) and the herpes simplex virus 1 (HSV-1, IC50 3.70 and 2.87 μmol/L), and 2 also inhibited Coxsackie virus B3 (IC50 0.71 μmol/L).

C19-Diterpenoid alkaloid arabinosides from an aqueous extract of the lateral root of Aconitum carmichaelii and their analgesic activities

Eight new C₁₉-diterpenoid alkaloid arabinosides, named aconicarmichosides E–L (1–8), were isolated from an aqueous extract of the lateral roots of Aconitum carmichaelii (Fu Zi). Their structures were determined by spectroscopic and chemical methods including 2D NMR experiments and acid hydrolysis. Compounds 1–8, together with the previously reported four neoline 14-O-arabinosides from the same plant, represent the only examples of glycosidic diterpenoid alkaloids so far. At a dose of 1.0 mg/kg (i.p.), as compared with the black control, compounds 1, 2, and 4–6 exhibited analgesic effects with >65.6% inhibitions against acetic acid-induced writhing of mice. Structure–activity relationship was also discussed.

8,4'-Oxyneolignane glucosides from an aqueous extract of "ban lan gen" (Isatis indigotica root) and their absolute configurations

Three pairs of glycosidic 8,4'-oxyneolignane diastereoisomers, named isatioxyneolignosides A-F (1-6), were isolated from an aqueous extract of Isatis indigotica roots. Their structures and absolute configurations were elucidated by comprehensive spectroscopic data analysis and enzyme hydrolysis. The validity of ΔδC8-C7 values to distinguish threo and erythro aryl glycerol units and Cotton effects at 235±5 nm to determine absolute configurations at C-8 in 1-6 and their aglycones (1a-6a) are discussed.

The pathological roles of NDRG2 in Alzheimer's disease, a study using animal models and APPwt-overexpressed cells

AIMS

To investigate the roles of N-myc downstream-regulated gene 2 (NDRG2) in the pathology of aging and neurodegenerative disease such as Alzheimer's disease (AD).

RESULTS

In this study, we confirmed the upregulation of NDRG2 in the brains of aging and AD animal models. To explore the role of NDRG2 in the pathology of AD at molecular level, we conducted a cell-based assay of highly expressed wild-type human APP695 SK-N-SH cells (SK-N-SH APPwt). By silencing and overexpressing gene of NDRG2, we demonstrated that NDRG2-mediated increase in Aβ_1-42 was through the pathways of BACE1 and GGA3. NGRG2 improved tau phosphorylation via enhanced activity of CDK5 and decreased Pin1, but it was not affected by GSK3β pathway. NDRG2 might also induce cell apoptosis through the extrinsic (caspase 8) apoptotic pathway by interaction with STAT3.

CONCLUSION

Our study confirmed the upregulation of NDRG2 in AD animal models and demonstrated its important roles in AD pathology. NDRG2 might be a potential target for studying and treatment of AD.

Diglycosidic indole alkaloid derivatives from an aqueous extract of Isatis indigotica roots

Six new indole alkaloid diglycosides named isatigotindolediosides A-F (1-6), along with three known analogs (7-9), were isolated from an aqueous extract of the Isatis indigotica roots (ban lan gen). Their structures including the absolute configurations were determined by comprehensive spectroscopic data analysis, combined with enzyme or acid hydrolysis, and comparison of experimental circular dichroism (CD) and calculated electronic circular dichroism (ECD) spectra. In the preliminary assays, compounds 3, 5, and 8 showed antiviral activity against Coxsackie virus B3.

Indole alkaloid sulfonic acids from an aqueous extract of Isatis indigotica roots and their antiviral activity

Six new indole alkaloid sulfonic acids (1-6), together with two analogues (7 and 8) that were previously reported as synthetic products, were isolated from an aqueous extract of the Isatis indigotica root. Their structures including the absolute configurations were determined by spectroscopic data analysis, combined with enzyme hydrolysis and comparison of experimental circular dichroism and calculated electronic circular dichroism spectra. In the preliminary assay, compounds 2 and 4 showed antiviral activity against Coxsackie virus B3 and influenza virus A/Hanfang/359/95 (H3N2), respectively.