ABSTRACT
ObjectiveTo screen and validate key enzyme genes affecting the polysaccharide content in different Polygonatum species and perform in-depth amino acid sequence analysis by transcriptomic analysis of P. zanlanscianense， P. kingianum， and P. cyrtonema rhizomes to enrich the transcriptome data of Polygonatum plants and provide references for polysaccharide biosynthesis mechanism and genetic improvement. MethodThe Polygonatum transcriptome was sequenced and analyzed using the Illumina NovaSeq high-throughput sequencing platform， and the differences in the transcriptomes of the three Polygonatum species were compared and according to the annotations of Nr， Gene Ontology （GO）， and Kyoto Encyclopedia of Genes and Genomes （KEGG） databases. The key enzymes in the polysaccharide metabolism pathway were screened， and the expression of key enzyme genes was clustered and correlated with the polysaccharide content. Finally， Real-time polymerase chain reaction （Real-time PCR） was performed to validate the eight key enzyme genes， and the key genes of polysaccharide biosynthesis were further screened for homologous gene sequence analysis in combination with sequencing results， followed by constructing phylogenetic trees， predicting motifs， conserved structural domains， protein sequence isoelectric points， and molecular weights， and constructing 3D protein structures by using homology modeling method. ResultThe annotation of the Nr database revealed that three Polygonatum species had the highest gene homology with Asparagus officinalis. GO database annotation results showed that three Polygonatum species differed significantly in binding， catalytic activity， metabolic processes， and cellular components， while the KEGG pathway annotation results indicated that three Polygonatum species differed significantly in the starch and sucrose metabolic pathway and galactose metabolic pathway. According to clustering analysis， correlation analysis， Real-time PCR， expression profiles， and structural and functional predictions of amino acid sequences， the key enzyme significantly affecting the polysaccharide content in different Polygonatum species was inferred to be β-fructofuranosidase （sacA）. ConclusionSacA may be the main influencing factor for the difference in polysaccharide content of Polygonatum， and is also an important reason why Polygonatum polysaccharides are mainly fructans.
ABSTRACT
Hirudin, an acidic polypeptide secreted by the salivary glands of Hirudo medicinalis (also known as "Shuizhi" in traditional Chinese medicine), is the strongest natural specific inhibitor of thrombin found so far. Hirudin has been demonstrated to possess potent anti-thrombotic effect in previous studies. Recently, increasing researches have focused on the anti-thrombotic activity of the derivatives of hirudin, mainly because these derivatives have stronger antithrombotic activity and lower bleeding risk. Additionally, various bioactivities of hirudin have been reported as well, including wound repair effect, anti-fibrosis effect, effect on diabetic complications, anti-tumor effect, anti-hyperuricemia effect, effect on cerebral hemorrhage, and others. Therefore, by collecting and summarizing publications from the recent two decades, the pharmacological activities, pharmacokinetics, novel preparations and derivatives, as well as toxicity of hirudin were systematically reviewed in this paper. In addition, the clinical application, the underlying mechanisms of pharmacological effects, the dose-effect relationship, and the development potential in new drug research of hirudin were discussed on the purpose of providing new ideas for application of hirudin in treating related diseases.
ABSTRACT
Patchouli ("Guanghuoxiang") or scientifically known as Pogostemon cablin Benth, belonging to the family Lamiaceae, has been used in traditional Chinse medicine (TCM) since the time of the Eastern Han dynasty. In TCM theory, patchouli can treat colds, nausea, fever, headache, and diarrhea. Various bioactive compounds have been identified in patchouli, including terpenoids, phytosterols, flavonoids, organic acids, lignins, glycosides, alcohols, pyrone, and aldehydes. Among the numerous compounds, patchouli alcohol, ß-patchoulene, patchoulene epoxide, pogostone, and pachypodol are of great importance. The pharmacological impacts of these compounds include anti-peptic ulcer effect, antimicrobial effect, anti-oxidative effect, anti-inflammatory effect, effect on ischemia/reperfusion injury, analgesic effect, antitumor effect, antidiabetic effect, anti-hypertensive effect, immunoregulatory effect, and others.For this review, we examined publications from the previous five years collected from PubMed, Web of Science, Springer, and the Chinese National Knowledge Infrastructure databases. This review summarizes the recent progress in phytochemistry, pharmacology, and mechanisms of action and provides a reference for future studies focused on clinical applications of this important plant extract.
