Five Pairs of Enantiomer as Rearrangement Products from Secoiridoids in Gentiana macrophylla Pall.

Five racemates (1-5) were isolated from Gentiana macrophylla, in which 2-5 were successfully separated into four pairs of enantiomers (2a and 2b, 3a and 3b, 4a and 4b, and 5a and 5b), whereas the resolution of 1 failed due to the hemiacetal functionality at the stereogenic center. Using electronic circular dichrosim calculation, the relationship of the molecular rotation direction and the carbon R/S chirality was revealed, and each pair of enantiomer was identified as (-)-(S)-gentianmacrol B (2a) and (+)-(R)-gentianmacrol B (2b), (-)-(S)-8-methoxy-gentianol (3a) and (+)-(R)-8-methoxy-gentianol (3b), (+)-(S)-8-methyl-gentianadine (4a) and (-)-(R)-8-methyl-gentianadine (4b), and (-)-(S)-gentianol (5a) and (+)-(R)-gentianol (5b). Besides, these compounds could be divided into two series, 1-2 containing the benzene ring moiety and 3-5 containing the pyridine ring moiety. Considering that their molecular skeleton could not be generated from the classical biosynthesis pathway in plants, the plausible biosynthesis pathways of 1-5 were deduced to be transformed from secoiridoids in G. macrophylla. Due to the significant difference in the pharmacological effect for the optical factor, our research provided new diverse molecules for further optical activity studies in drug research.

Transcriptome and metabolome analysis reveals mechanism of light intensity modulating iridoid biosynthesis in Gentiana macrophylla Pall.

Light intensity is a key factor affecting the synthesis of secondary metabolites in plants. However, the response mechanisms of metabolites and genes in Gentiana macrophylla under different light intensities have not been determined. In the present study, G. macrophylla seedlings were treated with LED light intensities of 15 µmol/m2/s (low light, LL), 90 µmol/m2/s (medium light, ML), and 200 µmol/m2/s (high light, HL), and leaves were collected on the 5th day for further investigation. A total of 2162 metabolites were detected, in which, the most abundant metabolites were identified as flavonoids, carbohydrates, terpenoids and amino acids. A total of 3313 and 613 differentially expressed genes (DEGs) were identified in the LL and HL groups compared with the ML group, respectively, mainly enriched in KEGG pathways such as carotenoid biosynthesis, carbon metabolism, glycolysis/gluconeogenesis, amino acids biosynthesis, plant MAPK pathway and plant hormone signaling. Besides, the transcription factors of GmMYB5 and GmbHLH20 were determined to be significantly correlated with loganic acid biosynthesis; the expression of photosystem-related enzyme genes was altered under different light intensities, regulating the expression of enzyme genes involved in the carotenoid, chlorophyll, glycolysis and amino acids pathway, then affecting their metabolic biosynthesis. As a result, low light inhibited photosynthesis, delayed glycolysis, thus, increased certain amino acids and decreased loganic acid production, while high light got an opposite trend. Our research contributed significantly to understand the molecular mechanism of light intensity in controlling metabolic accumulation in G. macrophylla.

Quantifying chemical correlations between fruits and processed fruit products: A non-targeted analysis approach.

Juices and beverages are produced by industry for long-distance distribution and shelf-stability, providing valuable nutrients. However, their nutritional value is often underestimated due to insufficient analytical methods. We have employed non-targeted analysis through a standardized analytical protocol, taking advantage of Data Independent Acquisition (DIA) technique and a novel Chromatographic Retention Behavior (CRB) data deconvolution algorithm. After analyzing 9 fruits and their products, correlations between fruits and their juices are accurately digitalized by similarities of their LC-MS fingerprints. We also specify non-targeted molecules primarily associate with nutrient loss in these analyzed juice products, including nitrogenous nutrients, flavonoids, glycosides, and vitamins. Moreover, we unveiled previously unreported fruit-characteristic metabolites, of which reconstituted-from-concentrate (RFC) juices contain over 40% of the content found in their fresh counterparts. Conclusively, our method establishes a quantitative benchmark for rational selection of RFC juices to substitute natural fruits.

Genomic characterization of WRKY transcription factors related to secoiridoid biosynthesis in Gentiana macrophylla.

Gentiana macrophylla is one of Chinese herbal medicines in which 4 kinds of iridoids or secoiridoids, such as loganic acid, sweroside, swertiamarin, and gentiopicroside, are identified as the dominant medicinal secondary metabolites. WRKY, as a large family of transcription factors (TFs), plays an important role in the synthesis of secondary metabolites in plants. Therefore, WRKY genes involved in the biosynthesis of secoiridoids in G. macrophylla were systematically studied. First, a comprehensive genome-wide analysis was performed, and 42 GmWRKY genes were identified, which were unevenly distributed in 12 chromosomes. Accordingly, gene structure, collinearity, sequence alignment, phylogenetic, conserved motif and promoter analyses were performed, and the GmWRKY proteins were divided into three subfamilies based on phylogenetic and multiple sequence alignment analyses. Moreover, the enzyme-encoding genes of the secoiridoid biosynthesis pathway and their promoters were then analysed, and the contents of the four secoiridoids were determined in different tissues. Accordingly, correlation analysis was performed using Pearson's correlation coefficient to construct WRKY gene-enzyme-encoding genes and WRKY gene-metabolite networks. Meanwhile, G. macrophylla seedlings were treated with methyl jasmonate (MeJA) to detect the dynamic change trend of GmWRKYs, biosynthetic genes, and medicinal ingredient accumulation. Thus, a total of 12 GmWRKYs were identified to be involved in the biosynthesis of secoiridoids, of which 8 (GmWRKY1, 6, 12, 17, 33, 34, 38 and 39) were found to regulate the synthesis of gentiopicroside, and 4 (GmWRKY7, 14, 26 and 41) were found to regulate the synthesis of loganic acid. Taken together, this study systematically identified WRKY transcription factors related to the biosynthesis of secoiridoids in G. macrophylla, which could be used as a cue for further investigation of WRKY gene functions in secondary metabolite accumulation.

Hollow Mesoporous Molybdenum Single-Atom Nanozyme-Based Reactor for Enhanced Cascade Catalytic Antibacterial Therapy.

Purpose: The remarkable peroxidase-like activity of single-atom nanozymes (SAzymes) allows them to catalyze the conversion of H2O2 to •OH, rendering them highly promising for antibacterial applications. However, their practical in vivo application is hindered by the near-neutral pH and insufficient H2O2 levels present in physiological systems. This study was aimed at developing a SAzyme-based nanoreactor and investigating its in vivo antibacterial activity. Methods: We developed a hollow mesoporous molybdenum single-atom nanozyme (HMMo-SAzyme) using a controlled chemical etching approach and pyrolysis strategy. The HMMo-SAzyme not only exhibited excellent catalytic activity but also served as an effective nanocarrier. By loading glucose oxidase (GOx) with HMMo-SAzyme and encapsulating it with hyaluronic acid (HA), a nanoreactor (HMMo/GOx@HA) was constructed as glucose-triggered cascade catalyst for combating bacterial infection in vivo. Results: Hyaluronidase (HAase) at the site of infection degraded HA, allowing GOx to convert glucose into gluconic acid and H2O2. An acid environment significantly enhanced the catalytic activity of HMMo-SAzyme to promote the further catalytic conversion of H2O2 to •OH for bacterial elimination. In vitro and in vivo experiments demonstrated that the nanoreactor had excellent antibacterial activity and negligible biological toxicity. Conclusion: This study represents a significant advancement in developing a cascade catalytic system with high efficiency based on hollow mesoporous SAzyme, promising the advancement of biological applications of SAzyme.

Total saponins from Rhizoma Panacis Majoris inhibit proliferation, induce cell cycle arrest and apoptosis and influence MAPK signalling pathways on the colorectal cancer cell.

Colorectal cancer (CRC) ranks third in incidence and second in mortality among all types of cancer, and due to its insidious onset and lack of early symptoms, it is usually diagnosed at a later stage. Saponins, a class of compounds abundant in plants, have been reported to possess prominent anti­tumour properties. The use of ginsenoside Rg3 in the clinical setting was authorized by the National Medicinal Products Administration of China. In the present study, total saponins from Rhizoma Panacis Majoris (RPMTG) were prepared, and the pharmacological mechanisms underlying the anti­CRC effects of RPMTG were investigated. The effect of RPMTG on the proliferation, cell cycle progression and apoptosis of HCT116 and SW620 cells were detected by MTT, flow cytometry and western blotting assays, and it was demonstrated that RPMTG could inhibit the proliferation of HCT116 and SW620 cells with IC50 values of 315.8 and 355.1 µg/ml, respectively, induce cell cycle arrest in the S and G0/G1 phase, and trigger apoptosis by downregulating the expression of the anti­apoptotic proteins Bcl­2, Bcl­xL and induced myeloid leukaemia cell differentiation protein Mcl­1, and increasing the expression of the pro­apoptotic proteins Bax and Bad, cleaved caspased­3 and poly(ADP)­ribose polymerase. These findings suggested that RPMTG induced apoptosis through mitochondrial­related pathways. In addition, RPMTG also decreased the expression of phosphorylated (p)­extracellular signal­regulated kinase and increased p­c­Jun N­terminal kinase (p­JNK) and p­p38. Moreover, the effects of RPMTG on cell proliferation and apoptosis were partially reversed when the JNK and p38 mitogen­activated protein kinase (MAPK) pathways were inhibited, indicating that RPMTG triggered apoptosis mainly via regulating JNK and p38 MAPK signalling. Therefore, RPMTG may have potential as an anti­CRC agent, and further evaluations are needed.

Anti-Rheumatoid Arthritic Effects of Paris Saponin VII in Human Rheumatoid Arthritis Fibroblast-Like Synoviocytes and Adjuvant-Induced Arthritis in Rats.

In the pathogenesis of rheumatoid arthritis (RA), rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) have tumor-like characteristics, mainly manifested by hyperproliferation and resistance to apoptosis and then it will erode the bone and cartilage, eventually leading to joint destruction. Paris saponin VII (PS VII) is an active compound derived from a traditional herbal medicine named Trillium tschonoskii Maxim, which has anti-tumor, analgesic, and immunomodulatory effects. However, its anti-RA effect has not yet been reported. This study was to investigate the effect of PS VII on two rheumatoid arthritis fibroblast-like synoviocytes lines (RA-FLS and MH7A) and adjuvant-induced arthritis (AIA) in rats. In vitro, the effects of PS VII on the proliferation, cell cycle, and apoptosis of RA-FLS and MH7A cells were detected by MTT, flow cytometry, and western blot analysis. In vivo, the effect of PS VII on the weight of the rat, paw swelling, ankle joint diameter, arthritis index, serum inflammatory cytokines (TNF-α, IL-6, and IL-1ß), histopathological assessment and apoptosis proteins in the synovial tissues were evaluated in AIA rats. The in vitro studies showed that PS VII inhibited the proliferation of RA-FLS and MH7A cells, induced S phase arrest and triggered cell apoptosis mainly through the mitochondrial apoptotic pathway and the regulation of JNK and p38 MAPK pathways. The in vivo studies revealed that PS VII could improve ameliorate body weight, paw swelling, ankle joint diameter, reduce the spleen and thymus index, suppress the production of TNF-α, IL-6 and IL-1ß, improve histopathological changes and regulate the expressions of apoptosis proteins in AIA Rats. In conclusion, PS VII could inhibit the proliferation and trigger apoptosis of RA-FLS and MH7A cells by regulating the mitochondrial apoptosis pathway and the JNK and p38 MAPK pathways, and alleviate the symptoms of RA, signifying it to be one of the potential anti-RA therapeutics.

Mangiferin inhibited neuroinflammation through regulating microglial polarization and suppressing NF-κB, NLRP3 pathway.

Inflammation plays important roles in the progress of neurodegenerative diseases, such as Parkinson's disease and Alzheimer's disease. Microglia is responsible for the homeostasis of the central nervous system (CNS), and involved in the neuroinflammation. Therefore, it could be potential in treatment of neurodegenerative diseases to suppress the microglia-mediated neuroinflammation. Mangiferin, a major glucoside of xanthone in Anemarrhena Rhizome, has anti-inflammatory, anti-diabetes, and anti-oxidative properties. However, the effect of mangiferin on the inflammatary responses of microglia cells are still poorly understand. In this study, we investigated the mechanism by which mangiferin inhibited inflammation in LPS-induced BV2 microglia cells. BV2 cells were pretreatment with mangiferin followed by LPS stimulation. In vitro assays, NO and cytokines production were quantified. Western blot and immunocytochemistry were used to examine the effect of mangiferin on the polarization of BV2 cells and signaling pathway. The results showed that mangiferin treatment significantly reduced NO, IL-1ß, IL-6 and TNF-α production, also reduced the mRNA and protein of iNOS and COX-2, promoted the polarization of inflammatory toward anti-inflammatory, and inhibited activation of NF-κB and NLRP3 inflammasome. These data suggest that mangiferin has an anti-neuroinflammatory property via regulating microglia macrophage polarization and suppressing NF-κB and NLRP3 signaling pathway, and may act as a potential natural therapeutic candidate for neuroinflammatory diseases.

Three new steroidal components from the roots of reineckia carnea.

A new coprostanol glycoside, 26-trihydroxy-16, 22-dioxo-3ß-[(α-L-rhamnopyranosyl)oxy]-5ß-cholestan-1ß-yl O-α-L-rhamnopyranosyl-(1→2)-ß-D-fucopyranoside (1) (25S)-5ß-spirostan-1ß,2ß,3ß, 4ß,5ß, 6ß-hexol (2), a new C-22 steroidal lactone saponin, (20 R)-16ß-trihydroxy-3ß-[(α-L-rhamnopyranosyl)oxy]-1ß-[(O-α-L-rhamnopyranosyl-(1→2)-ß-D-xylopyranosyl)oxy]-5ß-pregnane-20-oic acid γ-lactone (3) along with two known pregnane glycosides (4 and 5) were obtained from the roots of Reineckia carnea. Their structures were determined by 1 D, 2 D NMR, IR and MS data analysis. In addition, the cytotoxic activities in HT-29, HCT116, H1299 and A549 tumor cells of the isolated compounds (1 - 5) were determined by the MTT method. The results showed that only compound 1 exhibited weak effect against these cells with IC50 values ranging from 63.36 µM to 105.01 µM.

Polyphyllin VII induces apoptotic cell death via inhibition of the PI3K/Akt and NF­κB pathways in A549 human lung cancer cells.

Polyphyllin VII is an active compound isolated from Paris polyphylla, which is termed Chonglou in China. The present study was designed to investigate the underlying mechanisms of the antitumor effect of Polyphyllin VII in lung cancer cells. The cytotoxic effect of Polyphyllin VII in human lung cancer A549 cells was analyzed; the results revealed an IC50 value of 0.41±0.10 µM at 24 h. The associated mechanisms were investigated by phase­contrast microscopy, fluorescence microscopy, flow cytometry and western blot analysis. Exposure of A549 cells to Polyphyllin VII resulted in apoptosis. Pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF­κB, and wortmannin, an inhibitor of PI3K, both decreased the proportion of viable A549 cells in the presence of Polyphyllin VII. The ratio of apoptotic cells increased in the presence of wortmannin and PDTC. Western blot analysis revealed that PI3K, phosphorylated (p)­PI3K, Akt, p­Akt, NF­κB and p­NF­κB were downregulated following treatment with Polyphyllin VII. Increased caspase­3 activity, increased poly­(ADP­ribose) polymerase cleavage and a downregulation of inhibitor of caspase­activated DNase were observed following treatment with Polyphyllin VII, and these effects were enhanced by either wortmannin or PDTC. The present results revealed that Polyphyllin VII was able to induce apoptotic cell death in A549 human lung cancer cells via inhibition of the PI3K/Akt and NF­κB pathways.

Steroidal constituents from Helleborus thibetanus and their cytotoxicities.

Thibetanosides E-H (1-4), four new steroidal constituents including three rare sulfonates (2-4), were isolated from the roots and rhizomes of Helleborus thibetanus, together with nine known steroidal compounds (5-13). Their structures were elucidated by detailed spectroscopic analysis, including 1D and 2D NMR techniques and chemical evidence. In this study, compounds 2-13 were evaluated for their cytotoxic activities against HCT116, A549 and HepG2 tumor cell lines in vitro. Among them, compound 8 (thibetanoside C) showed cytotoxicities against A549 cells(IC50 39.6 ± 1.9 µmol·L-1) and HepG2 cells(IC50 41.5 ± 1.1 µmol·L-1), respectively. Compound 9 (23S, 24S)-24-[(O-ß-D-fucopyranosyl)oxy]-3ß, 23-dihydroxy-spirosta-5, 25(27)-diene-1ß-ylO-(4-O-acetyl- α-L-rhamnopyranosyl)-(1→2)-O-[ß-D-xylopyranosyl-(1→3)]-α-L-arabinopyranoside) showed cytotoxicity against HCT116 cells(IC50 33.6 ± 2.1 µmol·L-1).

Five new polyhydroxylated furostanol saponins from the rhizomes of Tupistra chinensis.

Five new polyhydroxylated furostanol saponins were isolated from the roots and rhizomes of Tupistra chinensis, and their structures were determined as tupistrosides J-N (1-5), together with four known furostanol saponins (6-9), on the basis of physico-chemical properties and spectral analysis. Among them, compounds 3 and 5 showed cytotoxicity against human cancer cell lines SW620 with IC50 values of 72.5 ± 2.4 and 77.3 ± 2.5 µmol·L-1, respectively. Compound 4 showed cytotoxicity against human cancer cell line HepG2 with IC50 value of 88.6 ± 2.1 µmol·L-1.

[Programmed cell death induced by drought stress in sprout tumble of Pinellia ternata].

To further study the mechanism of sprout tumble caused by drought,drought stress was simulating with 30% PEG 6000,physiological,and then the morphological changes of Pinellia ternata cells at different treatment time were detected. The results indicated that,along with the period of drought stress continued,the contents of chlorophyll and water potential were decreased,relative electrical conductivity,contents of soluble sugar and MDA increased. Sprout tumble of P. ternata first occurred on the fourth day during drought stress,large scale of sprout tumble appeared on the eighth day with about 73% of tumble rate. The nuclei exposed to drought stress for 2 days were flattened,lobed,invalidated or irregular in shape and significant showed the apoptotic morphological characteristics. Adenylate transferase( ANT) gene expressions were inhibited by drought,with the rapid increase of Caspase-3 enzyme activity,the cell death rate increased. All this proves that the essence of sprout tumble caused by drought is programmed cell death,which may be a self dormancy protection mechanism of P. ternata against adverse environment.

[Responses of seed germination of Astragalus membranaceus to light and temperature conditions accompanied with drought and salt stresses].

We studied the seed germination of Astragalus membranaceus under PEG and Na Cl osmotic stress gradients( 0,-0. 1,-0. 3,-0. 5,-0. 7 MPa) respectively applied with light( continuous light,light 12 h/dark 12 h circulation and continuous dark) and temperature( constant 15 ℃,15 ℃ 12 h/30 ℃ 12 h circulation and constant 30 ℃) treatments. The results showed as following: ① Under the light and temperature interactive treatments,total germination percentage( TGP) was restrained by high temperature and continuous light also decreased TGP under high temperature. Mean germination time( MGT) was not changed by light mode. Root development was enhanced by dark and low temperature. Shoot development was enhanced by light and high temperature. Hypocotyl length was enhanced by dark and high temperature. ② Under the light and temperature interactive treatments combined respectively with PEG and NaCl stress conditions,although the inhibitions of seed germination and growth were gradually strengthened with the increases of osmotic stresses,slight osmotic stress can promote seed germination. Under the same osmotic potential,the effects of PEG on TGPs and MGTs were stronger than that of NaCl. As the temperature increase,the seeds may change from photo-neutrality to photo-phobia. Decreased TGP under drought and continuous light interactive treatment is an adaptation strategy to avoiding drought. Hypocotyl growth accelerated under continuous dark treatment is an ecological trait which could increase dry matter input in stem and height for more light. Seed development under high concentration of NaCl treatment is better than that of PEG treatment due to low water potential caused by Na~+,which can enter into seed coat and promote water absorption.

STAT3/c-Myc Axis-Mediated Metabolism Alternations of Inflammation-Related Glycolysis Involve with Colorectal Carcinogenesis.

Chronic inflammation is a major driving factor for the development of colitis-associated cancer (CAC). It is extensively acknowledged that patients who have long-standing inflammation bowel disease are at high risk for developing CAC. However, the metabolic alteration by which chronic intestinal inflammation promotes colorectal cancer is unclear. In the present study, we constructed dextran sulfate sodium (DSS)-induced colitis mouse model to uncover possible alterations in the metabolism indexes. Interestingly, after DSS diet administration, the expression of metabolism indexes and c-Myc increased. Moreover, in vitro, we treated cells with IL-6 to simulate inflammatory microenvironment and found that glucose uptake, lactate production, and lactate dehydrogenase activity increased dramatically, mirroring what were observed in vivo. In addition, the associative inhibition of STAT3 and c-Myc could significantly block the expression of metabolic enzymes. With the inhibition of STAT3/c-Myc signaling, meanwhile, the upregulation of both cell glucose uptake and lactate production by IL-6 pretreatment was reduced simultaneously. Thus, our study indicates that inflammation could induce metabolic disorder by promoting STAT3 signaling and c-Myc activity. Collectively, we find that metabolic disruptions triggered by inflammatory signaling are associated with tumorigenesis via the STAT3/c-Myc axis.

[Effects of shading on key enzyme genesexpression and accumulation of saponins in Panax japonicus var. major].

To explore the effects of shading and the expression of key enzyme genes on the synthesis and accumulation of Panax japonicus var. major saponins, different shading treatments (0%, 30%,50%) of potted P. japonicus var. major were used as test materials, the expression of three key enzyme genes(CAS,DS,ß-AS) of leaves and rhizomes in different growth periods of P. japonicus var. major was determined by real-time quantitative PCR, the content of total saponins was determined by ultraviolet spectrophotometry. The results indicated that, in flowering stage, CAS,DS,ß-AS were highly expressed in the aerial parts of P. japonicus var. major, 30% shading treatment significantly inhibited the expression of CAS in leaves and promoted the expression of DS and ß-AS in stems, leaves and flowers, it was speculated that the main part of saponin synthesis was leaf in this stage. Both the expression levels of DS and ß-AS and changes in the content of total saponins in leaves showed a tendency of low-high-low throughout the growth cycle, correlation coefficient analysis showed that there was a positive correlation between them. Compared with control, the expression levels of DS and ß-AS and the content of total saponins were greatly enhanced under shading treatment, 30% shading treatment significantly promoted the accumulation of total saponins. Therefore, it is suggested that 30% shading treatment should be applied to the artificial cultivation of P. japonicus var. major, which is beneficial to the accumulation and quality improvement of saponins.

C19-Norditerpenoid Alkaloids from Aconitum szechenyianum.

Three new C19-norditerpenoid alkaloids (1⁻3), along with two known C19-norditerpenoid alkaloids (4,5), have been isolated from Aconitum szechenyianum. Based on extensive spectroscopic techniques (1D, 2D-NMR, IR, and MS) and chemical methods, their structures were established as szechenyianine D (1), szechenyianine E (2), szechenyianine F (3), 8-O-methyl-14-benzoylaconine (4), and spicatine A (5). The immunosuppressive effects of compounds 1⁻5 were studied using a ConA-induced or LPS-induced splenocyte proliferation model. In vitro tests showed that Compounds 2, 4, and 5 suppressed ConA-induced or LPS-induced splenocyte proliferation in a concentration-dependent manner. The CC50/IC50 values of 2, 4, and 5 suggested that these compounds were potential immunosuppressive agents for the treatment of autoimmune diseases characterized by arthritis, such as rheumatoid arthritis.

Steroidal Constituents from Roots and Rhizomes of Smilacina japonica.

Four new steroidal constituents (1-4) along with two known steroidal glycosides (5 and 6) were isolated from the roots and rhizomes of Smilacina japonica. Analysis of their physicochemical properties and spectroscopic profiles identified the compounds as (25S)-5α-spirostan-9(11)-en-3ß, 17α-diol (1); (25S)-5α-spirostan-9(11)-en-3ß, 12ß-diol (2); (25S)-5α-spirostan-9(11)-en-3ß, 17α-diol-3-O-ß-d-glucopyranoside (3); (25S)-5α-spirostan-9(11)-en-3ß, 17α-diol-3-O-ß-d-glucopyranosyl-(1→2)-[ß-d-glucopyranosyl-(1→3)]-ß-d-galactopyranoside (4); japonicoside B (5); and japonicoside C (6). All six compounds showed cytotoxic activity against SMMC-7712, Bel-7402, A549, H460, and K562 human cancer cells.

C19-Norditerpenoid Alkaloids from Aconitum szechenyianum and Their Effects on LPS-Activated NO Production.

Three new C19-norditerpenoid alkaloids (1-3), along with two known C19-norditerpenoid alkaloids (4-5) have been isolated from Aconitum szechenyianum. Their structures were established by extensive spectroscopic techniques and chemical methods as szechenyianine A (1), szechenyianine B (2), szechenyianine C (3), N-deethyl-3-acetylaconitine (4), and N-deethyldeoxyaconitine (5). Additionally, compounds 1-5 were tested for the inhibition of NO production on LPS-activated RAW264.7 cells with IC50 values of 36.62 ± 6.86, 3.30 ± 0.11, 7.46 ± 0.89, 8.09 ± 1.31, and 11.73 ± 1.94 µM, respectively, while the positive control drug dexamethasone showed inhibitory activity with IC50 value of 8.32 ± 1.45 µM. The structure-activity relationship of aconitine alkaloids were discussed.

Tangzhining exhibits a protective effect against cognitive dysfunction in diabetic rats.

Previous studies have suggested that diabetes significantly impairs the cognitive function. Tangzhining (TZN), as a kind of Traditional Chinese Medicine (TCM), has been widely used to treat diabetes in China. However, the effect of TZN on treatment of diabetes-induced learning and memory deficits has not been well documented. The present study was to investigate the effect of TZN on diabetes-induced learning and memory deficits and delineate the underlying molecular mechanism. Diabetic rats were randomly grouped and treated with various doses of TZN (0.47, 0.94 and 1.4 g/kg) by intraperitoneal injection. Using the Morris water maze, TZN treatment (0.94 g/kg and 1.4 g/kg) reduced markedly the escape latency and path length of diabetic rats. The morphological changes of pyramidal cells in hippocampus of diabetic rats were apparently reversed and improved by TZN treatment, in comparison with that in diabetic rats without TZN treatment. Moreover, the results of Western blot analysis showed that TZN treatment significantly increased the protein expression of glutamic acid decarboxylase (GAD) and excitatory amino acid carrier 1 (EAAC1) in hippocampus of diabetic rats. Furthermore, TZN treatment increased the protein expression of N-methyl-D-aspartic acid (NMDA) receptor subunits including NR1 and NR2B. Taken together, our data suggest that TZN sustains the balance between glutamate (Glu) and GABA by regulating GAD and EAAC1, and maintains the NMDA receptors activity for learning and memory function through regulating the subunits NR1 and NR2B.