Structural characterization, molecular dynamic simulation, and conformational visualization of a water-soluble glucan with high molecular weight from Gastrodia elata Blume.

Polysaccharides have been widely used in the development of natural drugs and health food. However, polysaccharide characterization lags due to inherently complicated features and the limitations of existing detection approaches. We aimed to provide new insight into the fine structure and conformational visualization of polysaccharides from Gastrodia elata Blume, a medicinal and edible plant. A water-soluble polysaccharide (GEP2-6) with the high molecular weight of 2.7 × 106 Da was first obtained, and its purity reached 99.2 %. Chemical and spectroscopic analyses jointly revealed that GEP2-6 was a glucan linked by α-(1 â†’ 4) and α-(1 â†’ 6) glycosidic bonds. After enzymolysis, the local structure of GEP2-6 included α-1,4-Glcp, α-1,6-Glcp, α-1,4,6-Glcp, and α-1-Glcp at a molar ratio of 31.27∶1.32∶1.08∶0.93. The glycosidic linkage pattern of repeating units was further simulated by a glycan database and spatial examination software. The good dissolution performance was interpreted by dynamics simulation and practical molecular characteristics. Spherical flexible chains and the porous stable conformation were corroborated using atomic force microscopy. In addition, GEP2-6 could effectively scavenge DPPH and hydroxyl radicals as a promising natural antioxidant. These efforts will contribute to the expansion of clinical applications of this G. elata polysaccharide and the structural elucidation for macromolecular polysaccharides combined with traditional and modern analysis techniques.

Rapid Identification of Alkaloids and Flavonoids in Fissistigma oldhamii var. longistipitatum by Ultra High-Performance Liquid Chromatography and Quadrupole Time-of-Flight Tandem Mass Spectrometry.

The herb Fissistigma oldhamii var. longistipitatum has been used for a long time in Asian folk medicine in the treatment of several diseases, including rheumatoid arthritis and other inflammatory conditions. Researchers in China and elsewhere have analyzed and characterized its chemical content. In this study, a UHPLC-Q-TOF-MS/MS method, run in both positive and negative modes, was used to identify the main chemical compounds in dichloromethane extracts of this F. oldhamii variant. A total of 64 compounds, including 44 alkaloids and 20 flavonoids, were rapidly identified or tentatively characterized by comparing the molecular ion peaks and MS2 mass spectrometry fragment ions, combined with the mass spectrometry information of reference substances, appropriate fragmentation ions and related literatures. For the first time, the developed UHPLC-Q-TOF-MS/MS analysis method allows for the determination of 64 compounds from extracts of the F. oldhamii variant. The method presented here produced results that will be useful in further studies of this herb.

Integrated dose-response metabolomics with therapeutic effects and adverse reactions may demystify the dosage of traditional Chinese medicine.

BACKGROUND: Traditional Chinese medicine (TCM) has been used to treat various diseases for thousands of years. However, the uncertainty of dosage as well as the lack of systemic evaluation of pharmacology and toxicology is one major reason why TCM remains mysterious and is not accepted worldwide. Hence, we aimed to propose an integrated dose-response metabolomics strategy based on both therapeutic effects and adverse reactions to guide the TCM dosage in treatment. METHODS: The proposed methodology of integrated dose-response metabolomics includes four steps: dose design, multiple comparison of metabolic features, response calculation and dose-response curve fitting. By comparing the changes of all metabolites under different doses and calculating these changes through superposition, it is possible to characterize the global disturbance and thus describe the overall effect and toxicity of TCM induced by different doses. Rhubarb, commonly used for constipation treatment, was selected as a representative TCM. RESULTS: This developed strategy was successfully applied to rhubarb. The dose-response curves clearly showed the efficacy and adverse reactions of rhubarb at different doses. The rhubarb dose of 0.69 g/kg (corresponding to 7.66 g in clinic) was selected as the optimal dose because it was 90% of the effective dose and three adverse reactions were acceptable in this case. CONCLUSION: An integrated dose-response metabolomics strategy reflecting both therapeutic effects and adverse reactions was established for the first time, which we believe is helpful to uncover the mysterious veil of TCM dosage. In addition, this strategy benefits the modernization and internationalization of TCM, and broadens the application of metabolomics.

Fuzzy identification of bioactive components for different efficacies of rhubarb by the back propagation neural network association analysis of UPLC-Q-TOF/MSE and integrated effects.

BACKGROUND: Rhei Radix et Rhizoma (rhubarb), as one of the typical representatives of multi-effect traditional Chinese medicines (TCMs), has been utilized in the treatment of various diseases due to its multicomponent nature. However, there are few systematic investigations for the corresponding effect of individual components in rhubarb. Hence, we aimed to develop a novel strategy to fuzzily identify bioactive components for different efficacies of rhubarb by the back propagation (BP) neural network association analysis of ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry for every data (UPLC-Q-TOF/MSE) and integrated effects. METHODS: Through applying the fuzzy chemical identification, most components of rhubarb were classified into different chemical groups. Meanwhile the integration effect values of different efficacies can be determined by animal experiment evaluation and multi-attribute comprehensive indexes. Then the BP neural network was employed for association analysis of components and different efficacies by correlating the component contents determined from UPLC-Q-TOF/MSE profiling and the integration effect values. Finally, the effect contribution of one type of components may be totaled to demonstrate the universal and individual characters for different efficacies of rhubarb. RESULTS: It suggested that combined anthraquinones, flavanols and their polymers may be the universal character to the multi-functional properties of rhubarb. Other components contributed to the individuality of rhubarb efficacies, including stilbene glycosides, anthranones and their dimers, free anthraquinones, chromones, gallic acid and gallotannins, butyrylbenzenes and their glycosides. CONCLUSIONS: Our findings demonstrated that the bioactive components for different efficacies of rhubarb were not exactly the same and can be systematically differentiated by the network-oriented strategy. These efforts will advance our knowledge and understanding of the bioactive components in rhubarb and provide scientific evidence to support the expansion of its use in clinical applications and the further development of some products based on this medicinal herb.

New compounds from the stems of Fissistigma oldhamii var. longistipitatum and their cytotoxic activities.

Two new aporphine alkaloids, (R)-1,2-methylenedioxy-3,9-dimethoxy-11-hydroxy-N- carbamoyl-noraporphine (1) and 3,10,11-trimethoxy-1,2-methylenedioxy-7-oxoaporphine(2), and one new dihydrochalcone, 4',5'-dimethoxy-2'-hydroxy-3',6'-quinodihydrochalcone (3), along with five known alkaloids were isolated from the ethanol extracts of the stems of Fissistigma oldhamii var. longistipitatum. The compounds were obtained by various classical column chromatographic methods, and the structure elucidation was completed primarily on the basis of spectroscopic analysis, such as UV, NMR and HR-ESI-MS. The isolated compounds were subjected to evaluate cytotoxic activities in vitro, compound 1 had activity against HL-60 and HELA (IC50 value of 8.4 µM and 5.2 µM, respectively), compound 2 against MCF-7 (IC50 value of 3.7 µM), compound 3 against HEPG2 (IC50 value of 10.8 µM), respectively.

Regulation of serum lipidomics and amino acid profiles of rats with acute myocardial ischemia by Salvia miltiorrhiza and Panax notoginseng herb pair.

BACKGROUND: Salvia miltiorrhiza and Panax notoginseng herb pair (DQ) has been widely used in traditional Chinese medicine for a long history to prevent and treat the coronary heart disease. However, its protective mechanisms against myocardial ischemia during coronary heart disease remain not well-understood. PURPOSE: In this study, we aimed to explore the protective mechanisms of DQ on myocardial ischemia from the perspective of serum lipidomics and amino acids (AAs). METHODS: Rats were orally administrated with low-dose DQ (L-DQ, 0.24 g/kg) and high-dose DQ (H-DQ, 0.96 g/kg) for two weeks and subcutaneously injected with isoproterenol (ISO, 65 mg/kg) for two consecutive days (13th and 14th days) to induce acute myocardial ischemia (AMI). Heart histopathology and serum biochemical indices were examined. The specifically altered serum lipid metabolites were profiled via lipidomics approach, while serum AA profiles were analyzed using UHPLC-TQ-MS/MS. RESULTS: Cardiac marker enzymes (CK, CK-MB, LDH and cTn-I) were significantly upregulated in AMI rats with some of which significantly dropped to normal level in L- and H-DQ groups. Serum TC, TG, HDL, LDL, VLDL and FFA were improved in AMI rats treatment with L- and H-DQ. Further, the PCA based on lipidomics showed serum lipid metabolites in L- and H-DQ groups were closer to control group than that in model group. Compared with model group, H-DQ pretreatment significantly reduced SM (d34:1) and CE (20:4), and increased FA (20:5), PC (26:1), TG (56:9), TG (54:7), MG (17:0), Cer (d32:0) and Cer (d34:0), whereas L-DQ significantly alleviated the perturbed levels of CE (20:4), FA (20:5), MG (17:0), and SM (d34:1). Moreover, there was a significant increment for leucine, isoleucine, valine, phenylalanine, lysine and glutamate but a significant reduction for tryptophan in the serum of rats in model group as compared to control group. Intriguingly, H-DQ could significantly decrease the levels of glutamate, lysine, isoleucine, and BCAAs (the sum of leucine, isoleucine and valine) after AMI, while L-DQ had no significant effects on the above altered AAs. The Western blotting results implied that H-DQ could promote the myocardial BCAA catabolism in AMI rats by activation of BCKDHA, whereas by inhibition of BCKDHK. CONCLUSION: This study presents evidence for the therapeutic effects of DQ on AMI injury, in part, via co-regulating lipid and AA metabolisms.

An integrated metabolomics strategy to reveal dose-effect relationship and therapeutic mechanisms of different efficacy of rhubarb in constipation rats.

The ambiguity of dose-effect relationship of many traditional Chinese medicines (TCMs) has always influenced their rational use in TCM clinic. Rhubarb, a preferred representative of cathartic TCM, is currently widely used that results in a diversity of its dosage. The aim of this study was to use an integrated metabolomics strategy to simultaneously reveal dose-effect relationship and therapeutic mechanisms of different efficacy of rhubarb in constipation rats. Six doses of rhubarb (0.135, 0.27, 0.81, 1.35, 4.05, and 8.1 g/kg) were examined to elucidate the laxative and fire-purging effects by pathological sections and UPLC-Q-TOF/MSE. The results showed that there existed serious lesions in the stomach and colon of model rats. And conditions were basically improved to some extent in rhubarb-treated groups. Through relative distance calculation based on metabolomics score plots, it suggested that the effective dose threshold (EC20-EC80 range) of rhubarb was from 0.31 to 4.5 g/kg (corresponding to 3.44-50.00 g in the clinic) in rat serum and 0.29-2.1 g/kg (corresponding to 3.22-23.33 g in the clinic) in feces. Then, 33 potential biomarkers were identified in total. Functional pathway analysis revealed that the alterations of these biomarkers were associated with 15 metabolic pathways, mainly including arachidonic acid metabolism, glycerophospholipid metabolism, steroid biosynthesis, primary bile acid biosynthesis and sphingolipid metabolism. Of note, different doses of rhubarb could alleviate endogenous disorders to varying degrees through regulating multiple perturbed pathways to the normal state, which might be in a dose-dependent manner and involved in therapeutic mechanisms. To sum up, integrated serum and fecal metabolomics obtained that rhubarb ranging from 0.31 to 2.1 g/kg is safe and effective for constipation treatment. Also, our findings showed that the robust metabolomics techniques would be promising to be more accurately used in the dose-effect studies of complex TCM, and to clarify syndrome pathogenesis and action mechanisms in Chinese medicine.

[Dose-toxicity-effect relationship between licorice combined with rhubarb in purgation].

The dose-toxicity-effect relationship between licorice combined with rhubarb in purgation was studied. A total of 108 ICR mice were divided into control group,model group,positive group,low,medium and high-dose rhubarb groups,and low,medium and high-dose rhubarb-liquorice decoction group. After 6 days of continuous administration of loperamide hydrochloride,the constipation model of mice was replicated,and each group was given lactulose,different doses of rhubarb and rhubarb-liquorice decoction for 14 days. After administration,the defecation characteristics,blood biochemistry,liver,kidney and colon pathological changes in each group were compared. Based on the objective weight given by factor analysis,the dose-toxicity-effect relationship was comprehensively analyzed by multi-index scoring method. Two common factors were extracted by factor analysis,representing effect and toxicity respectively. The results showed that rhubarb could exert a diarrhea effect at the dosage of 1/2,2 and 8 times of the high limit set forth in the Chinese Pharmacopoeia,increase the defecation volume and the intestinal tract propulsion rate,reduce the time of anal and the oral transmission,and increase the water content of feces. The combination with licorice could alleviate its diarrhea effect,especially at the dosage of 1/2 times of the high limit set forth in the Chinese Pharmacopoeia. However,rhubarb showed obvious hepatic and colon toxicities at the dosage of 2 and 8 times of the high limit set forth in the Chinese Pharmacopoeia,and the combination with licorice could significantly reduce its toxicity. It shows that licorice has a " mediating" effect on rhubarb by alleviating the purgation property and reducing the toxicity.

Elucidating dosage-effect relationship of different efficacy of rhubarb in constipation model rats by factor analysis.

ETHNOPHARMACOLOGICAL RELEVANCE: Rhei Radix et Rhizoma (rhubarb), as the preferred representative of cathartic drugs of traditional Chinese medicine (TCM), has a long history of medicinal use and multifarious functions that produce a wide range of dosage. In modern times, rhubarb and its prescriptions are not only used to treat common clinical diseases, but also achieve good results in the treatment of acute, dangerous, severe and difficult diseases. However, rhubarb also has an alias called "General", which means that its efficacy is relatively rapid. AIM OF THE STUDY: The present study was conducted to simultaneously elucidate dosage-effect relationship of rhubarb of different efficacy, "Removing accumulation with purgation" (E1) and "Clearing heat and purging fire" (E2), providing reference for the safe and effective usage of rhubarb. MATERIALS AND METHODS: Three-week-old rats were randomly divided into the normal control group (Con.), model group (Mod.) and rhubarb groups with six doses (0.135, 0.27, 0.81, 1.35, 4.05, 8.1 g/kg). We established a constipation model with gastrointestinal accumulated heat induced by dyspepsia, taking defecation characteristics observed by metabolic cages, alvine pushing rate, gastrointestinal hormones in serum, etc., as indicators of E1, and taking TG, Na+-K+-ATPase, inflammatory factors and proteins, etc., as indicators of E2. The factor analytic approach was used to systematically evaluate the two effects and analyze the corresponding dosage-effect relationship. RESULTS: The levels of Gas, AchE, TG, Na+-K+-ATPase, TNF-α, IL-1ß, (p-)NF-κB p65, (p-)p38, (p-)ERK and p-JNK in model rats increased significantly while the levels of defecation, fecal water content, MTL, SS, ET, NTS, VIP, JNK and TLR4 decreased. Compared with the Mod., in rhubarb groups, the increase of faeces, alvine pushing rate, most gastrointestinal hormones, etc., reflected the therapeutic efficacy of E1, and the reduction of TG, Na+-K+-ATPase, expression levels of inflammatory indexes, etc., reflected the impact of E2. After the analysis, the effective threshold dose ranging from 0.67 to 5.37 g/kg (corresponding to 7.44-59.67 g in the clinic) was in the EC20-EC80 range for E1 treatment and from 0.78 to 5.60 g/kg (equivalently clinical 8.67-62.22 g) was for E2 treatment. And the 1.6- and 1.2-fold rhubarb highest dose of Chinese Pharmacopoeia might be the optimal doses for E1 and E2 respectively. In general, however, the concentration of rhubarb liquid for overall efficacy is suggested to be between middle and highest dose of Chinese Pharmacopoeia. CONCLUSION: A constipation model was used to elucidate two main effects of rhubarb, which was consistent with the characteristics of TCM syndrome. In the wide range of rhubarb dosage, low doses might have little or no effect and although high concentrations of rhubarb liquid enhanced curative efficacy, it would also have certain side effects on the body. Therefore, scientific-based experiments and rational analysis by mathematical models could contribute to the safe and effective application of rhubarb in the clinic.

Studies of the Anti-amnesic Effects and Mechanisms of Single and Combined Use of Donepezil and Ginkgo Ketoester Tablet on Scopolamine-Induced Memory Impairment in Mice.

Ginkgo ketoester tablets (GT) and donepezil were a clinically used combination for the treatment of Alzheimer's disease (AD). The aim of the study was undertaken to investigate the antiamnesic effects of the two drugs alone and in combination through in vivo models of the Morris water maze along with in vitro antioxidants, acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The potential mechanisms were speculated by the activities of acetylcholine (ACh), AChE, superoxide dismutase (SOD), and malondialdehyde (MDA) and the protein expression of brain-derived neurotrophic factor (BDNF) and tyrosine protein kinase B (TrkB). The combination group showed a concentration-dependent inhibition of cholinesterase and antioxidation. As far as its mechanism was concerned, the combination of two drugs exerted excellent effects on oxidative stress, cholinergic pathway damage, and inactivation of the BDNF-TrkB signaling pathway. Additionally, to elucidate the binding mechanism of GT active ingredients into the structure of AChE, the results of molecular docking studies indicated that hydrogen and/or hydrophobic bonds might play an important role in their binding process. Thus, the combination of drugs could treat AD perfectly and further verify the scientific rationality of clinical medication.

Elucidating the interaction of kansui and licorice by comparative plasma/tissue metabolomics and a heatmap with relative fold change.

Although compatibility is highly advocated in traditional Chinese medicine (TCM), inappropriate combination of some herbs may reduce the therapeutic action and even produce toxic effects. Kansui and licorice, one of TCM "Eighteen Incompatible Medicaments", are the most representative cases of improper herbal combination, which may still be applied simultaneously under given conditions. However, the potential mechanism of their compatibility and incompatibility is unclear. In the present study, two different ratios of kansui and licorice, representing their compatibility and incompatibility respectively, were designed to elucidate their interaction by comparative plasma/tissue metabolomics and a heatmap with relative fold change. As a result, glycocholic acid, prostaglandin F2a, dihydroceramide and sphinganine were screened out as the principal alternative biomarkers of compatibility group; sphinganine, dihydroceramide, arachidonic acid, leukotriene B4, acetoacetic acid and linoleic acid were those of incompatibility group. Based on the values of biomarkers in each tissue, the liver was identified as the compatible target organ, while the heart, liver, and kidney were the incompatible target organs. Furthermore, important pathways for compatibility and incompatibility were also constructed. These results help us to better understand and utilize the two herbs, and the study was the first to reveal some innate characters of herbs related to TCM "Eighteen Incompatible Medicaments".