Latest ArticlesPanax quinquefolium L. is a valuable Chinese herbal medicine with a large market demand. It has a complex chemical composition and numerous biological activities. At present, research on P. quinquefolium is focused on its underground parts, with especial interest in its saponins. There are few studies on non-saponins and the aboveground parts of Panax quinquefolium. Current quality standards are based on the saponin contents, which does not address the other benefits of Panax quinquefolium. This paper summarizes progress on the chemical components, pharmacological effects, quality evaluation, and product development of P. quinquefolium in recent years, and provides references for its further R & D and comprehensive utilization.
This study establishes a quantitative analysis of multi-components by single marker (QAMS) method for the simultaneous determination of gallic acid, sodium danshensu, protocatechuic acid, protocatechuic aldehyde, vanillin, rosmarinic acid, salvianolic acid B, eugenol, cryptotanshinone and tanshinone IIA in Guanxinshutong capsules (Bambusae Concretio Silicea, Salvia miltiorrhiza, clove, borneol, Bambusae Concretio Silicea) by HPLC. Sample was loaded onto an Agilent C18 (ZORBAX Extend-RP C18, 250 mm × 4.6 mm, 5 µm) column and eluted with methanol-0.4% aqueous formic acid solution as a flow phase gradient, flow speed 1.0 mL·min-1, detection wavelength 280 nm, column temperature 35 ℃ and sample intake of 5 µL. Using protocatechuic acid as the internal reference, a relative correction factor was calculated and the durability was investigated, and the content of 10 components was calculated by QAMS and external standard method (ESM). The results show that the specificity, linear relationship, precision, repeatability, and stability of the 10 components were good. The average recovery was 98.20%-103.47% and RSD was 1.26%-2.84%. The relative positive factors and contents of the other nine components were calculated as gallic acid (0.759, 227.381), sodium tanshinol (3.630, 3.283), protocatechualdehyde (0.185, 0.150), vanillin (0.532, 65.213), rosmarinic acid (4.240, 1.035), salvianolic acid B (3.245, 18.204), eugenol (1.729, 9.265), cryptotanshinone (0.691, 1.449), and tanshinone ⅡA (0.702, 1.939). The results of QAMS were consistent with ESM analysis, and the relative error was between -3% and 3%. This method is stable and reliable, and can be used for the determination of 10 components in Guanxinshutong capsules.
This study was designed to obtain recombinant human thioredoxin (rhTXN) by gene cloning and prokaryotic expression, and evaluated its therapeutic effect in the mouse ulcerative colitis (UC) model induced by dextran sulfate sodium (DSS). The human thioredoxin gene TXN was cloned from the cDNA of Jurkat cells. The recombinant expression plasmid pCold TF-rhTXN was constructed by restriction enzyme digestion. After expression in E. coli BL21 (DE3), recombinant human thioredoxin was purified by a nickel column. Intact rhTXN recombinant protein was obtained after removal of the fusion partner-tag by enzyme digestion and the activity of disulfide reductase was detected by the insulin reduction method. The animal experiments in this study were performed in accordance with the ethical guidelines of the Laboratory Animal Welfare Ethical Review Committee of Nanjing University. Experiment ulcerative colitis was induced by providing mice with sterilized drinking water which contained 3% DSS. rhTXN was injected intraperitoneally. The therapeutic effect was studied by weight change, colon length and HE (hematoxylin and eosin) stained sections. In vivo imaging was used to study the targeting of rhTXN to DSS mice. The GSE107499 data set of GEO database was used to screen the hub genes at the lesional sites of UC and study the correlation with TXN. The experimental results showed that rhTXN was successfully expressed and purified with disulfide reductase activity. rhTXN (100 μg·kg-1) had a significant therapeutic effect on maintaining the weight change of mice (P = 0.000 5) and reducing intestinal injury (P < 0.000 1), and had a colon targeting effect on DSS mice. In GSE107499 data set, TXN in inflammatory sites of UC patients was significantly down regulated (P < 0.01) and negatively correlated with hub gene CD40 (P < 0.01) and positively correlated with hub gene fibronectin 1 (FN1) (P < 0.01). In this study, biologically active rhTXN was successfully prepared and proved to have a promising therapeutic effect on the DSS mouse model, and TXN gene was significantly correlated with the UC hub genes CD40 and FN1.
Rhei Radix et Rhizoma is one of the most used medicinal materials in China. Its original species are Rheum palmatum, Rh. tanguticum, and Rh. officinale. Rhei Radix et Rhizoma derived from different original species are significantly different in their active ingredients and pharmacological effects. To develop an accurate, rapid, and specific identification method, we obtained the chloroplast genomes of the three original species by Illumina Novaseq sequencing. We designed specific DNA barcodes from the hypervariable regions, which can accurately identify the three original species. The experimental results showed that the total length of the chloroplast genomes of Rh. tanguticum, Rh. officinale and Rh. palmatum were 161 039 bp, 161 093 bp, and 161 136 bp, respectively. All the three genomes were represented as typical quadripartite structures. A total of 131 genes, including 86 protein-coding genes, 37 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes were identified from each chloroplast genome. Five pairs of primers based on the hypervariable regions were designed to efficiently amplify 42 samples. Results confirmed that five hypervariable regions, rps16-trnQ, psaA-ycf3, psbE-petL, ndhF-rpl32, and trnT-trnL, can be used as specific DNA barcodes for the identification of Rh. tanguticum, Rh. officinale, and Rh. palmatum. These results provided genetic information for further species identification of Rhei Radix et Rhizoma, and improve the safety of this clinical medication as well as standardize the market for Rhei Radix et Rhizoma.
Solid dispersion, a dispersion system in which drug molecules are highly dispersed in carrier materials, has been commonly used to improve the solubility and dissolution rate of poorly soluble drugs. The miscibility between drug and carrier is crucial to improve the dissolution performance and stability of solid dispersion. Therefore, the selection of carrier types and the optimization of drug loading are very important. In the current study, the solubility parameter method and Flory-Huggins theory were used to predict the miscibility between olaparib (OLP) and different carriers (VA64, Soluplus, Plasdone S630 and Kollidon K29/32). Besides, the carrier material with good miscibility was experimentally screened by differential scanning calorimetry (DSC). The optimum of drug-carrier ratio was further performed based on the miscibility phase diagram of drug and carrier. Theoretical calculation and experimental evaluation showed that the miscibility of OLP and VA64 was the best, and the drug loading of 30% could meet the requirements of large drug loading and physical stability. Polarizing light microscope, X-ray powder diffraction, DSC and laser confocal Raman spectroscopy exhibited that OLP was amorphous form in the solid dispersion system. Powder dissolution test demonstrated that the solid dispersion showed significantly enhanced dissolution rate in comparison to crystalline OLP. In this study, theoretical calculation and experimental evaluation were used to screen the types of carriers and optimize the drug loading, which provides an efficient strategy for the selection of carrier and the amount used in solid dispersion.
Age-related macular degeneration (AMD) is one of the main causes of vision loss among middle-aged and elderly people worldwide. The prevention and treatment of AMD is a current topic of interest in ophthalmology but remains challenging. Oxidative stress-induced retinal pigment epithelial cell autophagic dysfunction, cellular senescence, and an abnormal immune inflammatory response are key pathogenic factors for AMD. Many bioactive ingredients of traditional Chinese medicine not only exert anti-oxidative, anti-inflammatory, anti-aging, and anti-apoptotic effects, but also prevent/block the occurrence of AMD through different pathways. This review summarizes our current understanding of the pathogenesis of AMD, the types of natural bioactive ingredients capable of treating AMD, as well as the known mechanisms by which these agents act, and may provide new strategies for the prevention and treatment of AMD.
Colorectal cancer is a common malignant tumor of digestive tract, and the risk of inflammatory bowel disease developing into colorectal cancer is significantly increased. Immune signaling pathways NF-κB, IL-6/STAT3, COX-2/PGE2, IL-23/Th17 and TLRs have been confirmed to promote the transformation from colitis to colorectal cancer. NOD2 and intestinal microbes also participate in the regulation of inflammation mediated carcinogenesis. Chronic inflammation is a potential risk for colorectal cancer, and anti-inflammatory drugs may play a chemical preventive role. In this review, we summarize the signaling pathways involved in inflammation-associated colon carcinogenesis and evaluate the chemoprophylaxis of colon cancer.
Da Chaihu decoction is a classic prescription for the treatment of cholecystitis that is widely used in clinical practice, and has a definite curative effect. However, due to its diverse components and complex functions, the traditional indexes fail to capture its overall efficacy. Therefore, this study analyzed and predicted the quality markers (Q-markers) of Da Chaihu decoction based on specific chromatogram and network pharmacology to provide a reference for the comprehensive control of the quality. The study obtained 35 potential practical components of Da Chaihu decoction through virtual screening. The specific chromatogram of 15 batches of Da Chaihu decoction was established by HPLC-DAD with neohesperidin as a reference. Compared with the chromatographic peaks and the reference substance, the chemical components were assigned to predict the nine components of albiflorin, paeoniflorin, naringin, hesperidin, neohesperidin, baicalin, wogonoside, saikosaponin b2, saikosaponin b1 as Q-markers of Da Chaihu decoction. Finally, the network of the "components-key targets-signal pathways-biological processes" was constructed by network pharmacology to explore the mechanism of Da Chaihu decoction in treating cholecystitis to clarify the accuracy of Q-markers. The results indicated that potential Q-markers could act on multiple targets to regulate inflammatory and metabolism, and then combine to treat cholecystitis. Q-markers could combine with the pharmacologic action of Da Chaihu decoction, which could elucidate the overall efficacy of Da Chaihu decoction. This study explored the Q-markers of Da Chaihu decoction combined with the specific chromatogram and network pharmacology, which provided a basis for the quality control and evaluation of Da Chaihu decoction.
The amorphous solid dispersion is one of the most effective formulation approaches to enhance the oral bioavailability of poorly water-soluble drugs. However, the amorphous drugs tend to crystallize during storage or dissolution due to inadequate formulations, preparation techniques, storage and dissolution conditions, thus negating their advantages. Meanwhile, it is often difficult to establish in vitro-in vivo correlation for amorphous solid dispersions owing to the difference between dissolution media and physiological environments and between the apparent concentration and membrane transport flux, the dynamic process of the in vivo absorption, which put great challenges to the development of amorphous solid dispersion products. This review covers the recent progress on the mechanistic study of the in vitro dissolution and in vivo absorption of amorphous solid dispersions, aiming to provide guidance for the formulation development of poorly soluble drugs.
MYB transcription factors, one of the largest transcription factor families in plants, play an important role in signal transduction, plant growth and plant resistance. In this study a full-length cDNA of the PnMYB1R1 gene was cloned from Panax notoginseng. Sequence analysis, prokaryotic expression and purification, subcellular location, transcriptional activity analysis, tissue-specific analysis and expression analysis under different abiotic stresses was performed. The open reading frame (ORF) of PnMYB1R gene was 738 bp, encoding a protein of 245 amino acids with a predicted molecular mass (MW) of 27.0 kD. The sequence analysis and polygenetic analysis indicated that the PnMYB1R1 protein contains a conserved R3 domain, belonging to TRF-like protein in 1R-MYB-type transcription factors. The recombinant PnMYB1R1 protein was expressed in Escherichia coli BL21(DE3) cells using the prokaryotic expression vector pET28a-PnMYB1R1 and was purified. Subcellular localization analysis showed that PnMYB1R1 was localized in the nucleus. Transcriptional activity analysis indicated that the PnMYB1R1 transcription factor has transcriptional activation activity. Expression analysis indicated that PnMYB1R1 was primarily expressed in roots, followed by stems and leaves, and then rootlets. The expression level of PnMYB1R1 in root, stems, leaves and rootlets was influenced by salt, low temperature and drought treatment, while the abundance of PnMYB1R1 was significantly induced by salt stress in these tissues. These results provide valuable insights into the role of 1R-MYB transcription factors in plant defense.