Latest ArticlesPlant-derived triterpenoids constitute a large and structurally diverse class of natural products with various implications in industrial and pharmaceutical uses. The oleanane type triterpenoids are widely known for their pharmacological and/or biological activities. The biosynthesis pathway of oleanane triterpenoids is divided into three stages:precursor supply, skeleton synthesis, and terpenoids synthesis. Plant cytochrome P450 monooxygenases enzymes (P450s) are involved in the synthesis and diversification of natural products, and are responsible for other modifications of terpenoids, such as formation of triterpenoids. P450s-catalyzed structural modification prior to glycosylation is crucial for diversification and functionalization of triterpenoid scaffolds. In this paper, the catalyses of P450s on β-amyrin and oleanolic acid in oleanane type triterpenoid saponins biosynthesis were reviewed. Presenegenin is a major aglycon of Polygala saponins. The CYP716A249 in Polygala tenuifolia was used as an example to other P450s participating in the possible biosynthetic pathways of presenegenin. These results provide references for elucidation of the biosynthesis pathways of plant-derived oleanane type triterpenoids.
Phosphoglycerate kinase 1 (PGK1) is a key metabolic enzyme in the glycolysis pathway, which catalyzes the transfer of 1, 3-bisphosphoglycerate (1, 3-BPG) to 3-phosphoglycerate (3-PG) with ATP production. Over-expression of PGK1 has been observed in many types of malignance. Besides as a metabolic enzyme, PGK1 can also act as a protein kinase, which promotes the development and progression of tumors and correlates with chemoradiotherapy resistance and poor survival of cancer patients by regulating tumor cell metabolism. Functions of PGK1 were summarized in this article to provide theoretical basis for PGK1-targeting drug development.
In this study, 13 xyloglucan endotransglycosylases/hydrolases (XTHs) and 8 expansin (EXPs) were screened from safflower floret transcriptome database. Through correlation analysis between the safflower gene expression profile chip and the corolla development, only 4 XTHs (CtXTH1-4) and 1 EXP (CtEXP1) have positive relevance with corolla elongation (r ≥ 0.60) and were therefore validated by qRT-PCR. The full length of these genes were cloned by RACE. According to the bioinformatic analysis, CtXTH1 correlated with the development of the floret, and the expression pattern analysis indicated that CtXTH1 had accumulated in the floret. The recombinant vector (pMT39-CtXTH1) was constructed for gene transformation. Overexpression of CtXTH1 significantly increased the corolla length (about 5.34% to 10.25%) and corolla weight (about 30.00% to 36.02%) in transgenic safflower. The overexpression lines also showed an increasing tendency in the weight of seeds, average number of corollas per cone and average number of seeds in each cone. Meanwhile, overexpression of CtXTH1 had no significant effect on flavonoids. According to the corolla microstructure, the OVX-line tubular part of floret exhibited a looser and irregular character. These data suggested that CtXTH1 can potentially increase relaxation of the tissues and boost corolla elongation. Our study provides a valuable clue for plant breeding in the future.
To provide a basis for the establishment of the commodity grade of Astragali Radix (AR), we compared the chemical components and the anti-fatigue effect of different grades of AR. The components of primary metabolites were analyzed by 1H NMR and the contents of five flavonoids were determined by HPLC-UV with different grades of AR. Fatigue efficacy of different grades of AR was compared. All the procedures were approved by the Laboratory Animal Ethics Committee of the Shanxi University. The results showed that the content of water soluble extracts (WSE) of the Grade Ⅱ AR was the lowest, and 21 compounds were identified through 1H NMR spectrum. There are 3 components showing a higher content in the Grade-top AR, and 7 components were higher in the Grade-Ⅳ, and 7 other components were higher in the Grade-Ⅱ AR. Total flavonoid content was the highest in Grade-Ⅱ but it was the lowest in the Grade-Ⅳ. Pharmacodynamic results showed that AR could significantly enhance the exhaustion time of rats and improve the biochemical indexes of serum and gastrocnemius muscle, and the best anti-fatigue effect was observed with Grade -Ⅱ AR. Therefore, chemical composition and efficacy index were used to evaluate the quality of different grades of AR, and the quality evaluation approach was established based on chemical and pharmacological effects to provide a scientific basis for the development of AR. The study may provide useful information for construction of the quality grade standard of AR.
The roots and flowers of Gentiana waltonii and Gentiana robusta are used as Tibetan herb Jie-Ji in traditional Tibetan medicine, with iridoids as the main active ingredient and index components. To study the pathway of iridoid biosynthesis, roots, stems, leaves and flowers of G. waltonii and G. robusta were subjected to a high-throughput transcriptomic sequencing analysis by Illumina HiseqXTen. After removing insignificant reads and de novo splicing, 79 455 and 78 466 unigenes were obtained from G. waltonii and G. robusta respectively, with average length as 834 bp and 862 bp. The unigene GO functions could be divided into three categories of 65 branches. The unigenes were aligned in KOG database and were classified into 25 classes according to function. In KEGG database, 315 and 340 unigenes of G. waltonii and G. robusta were implicated in 20 standard secondary metabolic pathways, respectively. Furthermore, 80 and 57 unigenes of the two species were analyzed to encode 24 key enzymes in the pathway related to iridoid biosynthesis. There were differences in gene expression among different organs. Based on sequence data, significant amounts of SSRs, SNPs and InDels were detected in each dataset. This study provides a platform for further development of molecular markers, excavation of functional genes, and research into metabolic pathways and their regulatory mechanism within G. waltonii and G. robusta.
The compatibility of traditional Chinese medicines (TCM) includes the compatibility of single herb, effective parts and the effective ingredients of TCM herbs. Compared with the compatibility of Chinese herbal medicine, the compatibility between effective parts and effective ingredients of TCM has become a breakthrough point in the study of compatibility. It provides a new method for precise medication research of TCM, which is bound to become an important driving force in the process of precision medicine research. In this paper, we elabo rate the strategy of the compatibility and proportion in TCM components from five aspects:the compatibility mode of effective components in TCM, the screening method of compatibility of components in TCM, the selection of compatibility component dose, the design method of proportion test and the optimization research of compatibility and proportion.
Protein acetylation is a process of adding an acetyl group to a protein lysine residue with the help of acetyltransferase, which is a pivotal protein post-translational modification linking acetyl-CoA metabolism and cell signal transduction. Recently, the development of mass spectrometry has deepened our understanding of lysine acetylation. Lysine acetylation is involved in many processes such as gene transcription, protein degradation, cellular metabolism, and stress response, which affects biological processes by regulating protein interactions, activity, stability and localization. Protein acetylation is widely happened and plays important regulatory roles in a diversity of human diseases such as metabolic diseases, tumors and cardiovascular diseases. Besides, deacetylase inhibitors have displayed a great potential in the treatment of various diseases especially tumors and metabolic associated diseases. In this review, we summarized the advances and application of acetylation, and discussed the remaining problems in this area.
Among various technologies used in drug design and discovery, deep learning is still in its infancy. Recently, deep learning approaches have been rapidly developed and applied to address various problems in drug discovery, including generation of virtual compound library, prediction of compound activity, metabolism and toxicity, and prediction of organic synthesis routes. Compared with the traditional machine learning methods, the prediction power of deep learning did not show significant improvement. However, proactively learning and automatically feature extraction bring advantages for deep learning approaches. Compared to first principle-based computational chemistry methods, deep learning can not be generalized because it depends on large-scale and highquality annotated data sets. But its molecular representation with single-atom atomic environment vectors could be useful for computational chemists. As an emerging technology, deep learning, especially the unsupervised learning method that does not rely on large datasets with labels, is gradually improving. It is expected that someday deep learning method will become practical for drug discovery.
Enzymes play crucial functional roles in all biological processes. Enzymatic inhibitors can regulate enzyme activity and may become the starting point for drug discovery. Mass spectrometry (MS) has the advantage for rapid qualitative and quantitative analyses of compounds and enzyme reactions, emerging as an important analytical tool in enzyme inhibitor screening assay for drug discovery. This review will highlight recent advances in the inhibitor screening assay using MS and related techniques, including frontier affinity chromatography, immobilized enzyme beads, ultrafiltration, surface plasmon resonance, capillary electrophoresis and microfluidic chips. The existing MS methods for screening enzyme inhibitor were divided into two types:affinity screening and activity screening.
Amyotrophic lateral sclerosis (ALS) is among the most common type of motor neuron diseases, and its pathogenesis remains unclear. In recent years, our understanding of the genetic basis of ALS has led to the development of various ALS disease models, which allow for screening of ALS-related drugs and treatment methods. This review focuses on the research progress of ALS, summarizes the systems of commonly used experi mental animal models, including transgenic animals, gene knockout approaches and autonomous animal models, points to the problems needing attention in standardized ALS non-clinical research, and proposes the criteria for selection of standardized R&D model.