Chemical component analysis of the traditional Chinese medicine Guipi Tang and its effects on major depressive disorder at molecular level.

Ethnopharmacological relevance: Guipi Tang (GPT) is a widely used traditional Chinese medicine that is used to treat major depressive disorder. However, the molecular mechanisms of its effects remain unclear. Aim of the study: This study aimed to investigate the antidepressant-like effects of GPT and explore its underlying molecular mechanisms. Materials and methods: Male Sprague-Dawley rats were subjected to a chronic unpredictable mild stress (CUMS) procedure and treated with various doses of GPT, with fluoxetine treatment as a positive control. Behavioural tests (including sucrose preference test, novelty-suppressed feeding test, open-field test and forced swim test), terminal deoxynucleotidyl transferase dUTP nick end labeling and enzyme-linked immunosorbent assay were conducted. The levels of Bax, Bcl-2, cleaved caspase-3, PI3K, p-PI3K, AKT, p-AKT, BDNF, TrkB and CREB or p-CREB were assessed at the protein level using western blotting or immunofluorescence. Results: GPT consists of mainly known drugs, such as liquiritin and ginsenosides. It reversed depressive behaviours and decreased cell apoptosis in the hippocampi of CUMS rats. It significantly upregulated the protein level of Bax, p-Akt, p-PI3K, BDNF, TrkB and p-CREB and downregulated the level of cleaved caspase-3 and Bcl-2. Conclusions: GPT had anti-depressive activity as indicated by the amelioration of depression-like behaviour and the inhibition of hippocampal neuronal apoptosis in CUMS rats. This inhibition was mediated partly by modulating the PI3K/Akt and/or BDNF/TrkB/CREB pathway, in which, glycosides, the main components of GPT, might be involved.

Naoxintong Capsule for Secondary Prevention of Ischemic Stroke: A Multicenter, Randomized, and Placebo-Controlled Trial.

OBJECTIVE: To examine whether the combination of Naoxintong Capsule with standard care could further reduce the recurrence of ischemic stroke without increasing the risk of severe bleeding. METHODS: A total of 23 Chinese medical centers participated in this trial. Adult patients with a history of ischemic stroke were randomly assigned in a 1:1 ratio using a block design to receive either Naoxintong Capsule (1.2 g orally, twice a day) or placebo in addition to standard care. The primary endpoint was recurrence of ischemic stroke within 2 years. Secondary outcomes included myocardial infarction, death due to recurrent ischemic stroke, and all-cause mortality. The safety of drugs was monitored. Results were analyzed using the intention-to-treat principle. RESULTS: A total of 2,200 patients were enrolled from March 2015 to March 2016, of whom 143 and 158 in the Naoxintong and placebo groups were lost to follow-up, respectively. Compared with the placebo group, the recurrence rate of ischemic stroke within 2 years was significantly lower in the Naoxintong group [6.5% vs. 9.5%, hazard ratio (HR): 0.665, 95% confidence interval (CI): 0.492-0.899, P=0.008]. The two groups showed no significant differences in the secondary outcomes and safety, including rates of severe hemorrhage, cerebral hemorrhage and subarachnoid hemorrhage (P>0.05). CONCLUSION: The combination of Naoxintong Capsule with standard care reduced the 2-year stroke recurrence rate in patients with ischemic stroke without increasing the risk of severe hemorrhage in high-risk patients. (Trial registration No. NCT02334969).

Characterization of the fungal gibberellin desaturase as a 2-oxoglutarate-dependent dioxygenase and its utilization for enhancing plant growth.

The biosynthesis of gibberellic acid (GA(3)) by the fungus Fusarium fujikuroi is catalyzed by seven enzymes encoded in a gene cluster. While four of these enzymes are characterized as cytochrome P450 monooxygenases, the nature of a fifth oxidase, GA(4) desaturase (DES), is unknown. DES converts GA(4) to GA(7) by the formation of a carbon-1,2 double bond in the penultimate step of the pathway. Here, we show by expression of the des complementary DNA in Escherichia coli that DES has the characteristics of a 2-oxoglutarate-dependent dioxygenase. Although it has low amino acid sequence homology with known 2-oxoglutarate-dependent dioxygenases, putative iron- and 2-oxoglutarate-binding residues, typical of such enzymes, are apparent in its primary sequence. A survey of sequence databases revealed that homologs of DES are widespread in the ascomycetes, although in most cases the homologs must participate in non-gibberellin (GA) pathways. Expression of des from the cauliflower mosaic virus 35S promoter in the plant species Solanum nigrum, Solanum dulcamara, and Nicotiana sylvestris resulted in substantial growth stimulation, with a 3-fold increase in height in S. dulcamara compared with controls. In S. nigrum, the height increase was accompanied by a 20-fold higher concentration of GA(3) in the growing shoots than in controls, although GA(1) content was reduced. Expression of des was also shown to partially restore growth in plants dwarfed by ectopic expression of a GA 2-oxidase (GA-deactivating) gene, consistent with GA(3) being protected from 2-oxidation. Thus, des has the potential to enable substantial growth increases, with practical implications, for example, in biomass production.

Variable selection for discriminating herbal medicines with chromatographic fingerprints.

When discriminating herbal medicines with pattern recognition based on chromatographic fingerprints, typically, the majority of variables/data points contain no discrimination information. In this paper, chemometric approaches concerning forward selection and key set factor analysis using principal component analysis (PCA), unweighted and weighted methods based on the inner- and outer-variances, Fisher coefficient from the between- and within-class variations were investigated to extract representative variables. The number of variables retained was determined based on the cumulative variance percent of principal components, the ratio of observations to variables and the factor indicative function (IND). In order to assess the methods for variable selection and criteria levels to determine the number of variables retained, the original and reduced datasets were compared with Procrustes analysis and a weighted measure of similarity. Moreover, the tri-variate plots of the first three PCA scores were used to visually examine the reduced datasets in low dimensional space. Herbal samples were finally discriminated by use of Bayes discrimination analysis with the reduced subsets. The case study for 79 herbal samples showed that, the methods of forward selection associating the variables with the loadings closest to 0 and key set factor analysis were preferable to determine the representative variables. Procrustes analysis and the weighted measure were not indicative to extract representative variables. High matching between the original and reduced datasets did not suggest high prediction accuracy. Visually examining the PC1-PC2-PC3 scores projection plots with the reduced subsets, not all the herb samples could be separated due to the complexity of chromatographic fingerprints.

Determination of volatile components in ginger using gas chromatography-mass spectrometry with resolution improved by data processing techniques.

Ginger is widely used as either a food product or an herbal medicine in the world. In this paper, a method was developed for determining volatile components in essential oils from both dried and fresh ginger by use of gas chromatography-mass spectrometry (GC-MS) and chemometric approaches. With the resolution improvement by chemometric methods upon two-dimensional data from GC-MS, the drifting baseline can be corrected. In addition, the peak purity can be assessed and the number of chemical components and their stepwise elution in the peak clusters can be identified. The peak clusters investigated are then resolved into pure chromatograms and related mass spectra for each of the components involved. Finally, with the pure chromatograms and related mass spectra obtained, the chemical components can be qualitatively identified based on the similarity searches in the MS databases and the chromatographic retention times. Quantitative determination can be conducted using the overall volume integration approach. The results showed that 140 and 136 components were separated and that 74 and 75 of them were tentatively identified, which accounted for about 62.82 and 47.11% of the total relative content for dried and fresh ginger, respectively. In comparison with the chromatographic fingerprints of essential oils from dried and fresh ginger, 60 of the volatile components determined match with each other. The study demonstrated that the use of chemometric resolution based on two-dimensional data can mathematically enhance the separation ability of GC-MS and assist qualitative and quantitative determination of chemical components separated from complicated practical systems such as foods, herbal medicines, and environmental samples.

Correction of retention time shifts for chromatographic fingerprints of herbal medicines.

In this study, the combination of chemometric resolution and cubic spline data interpolation was investigated as a method to correct the retention time shifts for chromatographic fingerprints of herbal medicines obtained by high-performance liquid chromatography-diode array detection (HPLC-DAD). With the help of the resolution approaches in chemometrics, it was easy to identify the purity of chromatographic peak clusters and then resolve the two-dimensional response matrix into chromatograms and spectra of pure chemical components so as to select multiple mark compounds involved in chromatographic fingerprints. With these mark components determined, the retention time shifts of chromatographic fingerprints might be then corrected effectively. After this correction, the cubic spline interpolation technique was then used to reconstruct new chromatographic fingerprints. The results in this work showed that, the purity identification of the chromatographic peak clusters together with the resolution of overlapping peaks into pure chromatograms and spectra by means of chemometric approaches could provide the sufficient chromatographic and spectral information for selecting multiple mark compounds to correct the retention time shifts. The cubic spline data interpolation technique was user-friendly to the reconstruction of new chromatographic fingerprints with correction. The successful application to the simulated and real chromatographic fingerprints of two Cortex cinnamomi, fifty Rhizoma chuanxiong, ten Radix angelicae and seventeen Herba menthae samples from different sources demonstrated the reliability and applicability of the approach investigated in this work. Pattern recognition based on principal component analysis for identifying inhomogenity in chromatographic fingerprints from real herbal medicines could further interpret it.

Analysis of volatile components from Cortex cinnamomi with hyphenated chromatography and chemometric resolution.

In this paper, the combination of hyphenated chromatography and chemometric resolution was investigated as a method to qualitatively and quantitatively determine volatile components in Cortex cinnamomi from four main producing areas. With the help of chemometric resolution approaches, whether the chromatographic elution of chemical components is featured by "first-in-first-out" or embedded peaks could be determined. Upon this useful information obtained, the matrix data generated by hyphenated chromatography could be uniquely resolved into pure chromatogram and spectrum of each chemical component involved followed by qualitative and quantitative analysis. The results obtained in this work showed that, 94, 88, 93 and 89 volatile components were separated and 63, 60, 60 and 58 of them qualitatively and quantitatively determined representing about 93.39, 93.62, 92.03 and 92.59% of the total relative content, respectively. The combination of hyphenated chromatography with chemometric resolution could greatly enhance the chromatographic separation and spectral qualitatively determination ability so as to qualitatively and quantitatively detect many more volatile components and improve the analysis accuracy.

Information theory applied to chromatographic fingerprint of herbal medicine for quality control.

At present, the construction of chromatographic fingerprints plays an important role in the quality control of complex herbal medicines. In this work, information theory was applied to obtain chromatographic fingerprints with good performance. Moreover, according to the characteristics of the chromatographic fingerprints obtained, some modifications of the calculation of the information content were conducted. In comparison with the information content from several chromatographic fingerprints obtained, reliable chromatographic fingerprints with a high separation degree and uniform concentration distribution of chemical components could be determined. The successful application of information theory with modification to simulated chromatographic fingerprints together with real herbal medicines such as Rhizoma chuanxiong and Ginkgo biloba from different sources demonstrated clearly that the proposed method to determine chromatographic fingerprints was reasonable and reliable and it was user-friendly. Chromatographic fingerprints determined with high separation degrees and uniform concentration distribution of chemical ingredients might also chemically represent characteristic components of herbal medicines for quality control.