Latest ArticlesThe objective of this research was to clone 1-deoxy-D-xylulose 5-phosphate reductoisomerase gene (MoDXR) and its promoter sequence from Morinda officinalis and carry out bioinformatic analysis, cis-acting elements analysis, and prokaryotic expression. On the basis of the MoDXR gene sequence obtained from the M. officinalis transcriptome and with NCBI-ORFfinder analysis, a pair of specific primers were designed, and used for RT-PCR amplification. The promoter region sequence at the 5' end of MoDXR gene was isolated by the genome walking technique. Localization of MoDXR was carried out by subcellular analysis. The prokaryotic expression plasmid pET-28a-MoDXR was constructed and transfected into Escherichia coli BL21(DE3) chemically-competent cells; the recombiant plasmid expressed fusion protein after the induction by IPTG. The full-length cDNA of MoDXR was 2 015 bp, and open reading frame (ORF) size was 1 425 bp, and it encoded 474 amino acid residues and had a molecular mass of 51.27 kD. Sequence comparison with BlastP to the NCBI database revealed that MoDXR had high sequence similarity with many other DXRs, such as Coffea arabica DXR (CaDXR) and Rauvolfia verticillata DXR (RvDXR). A phylogenetic tree revealed that MoDXR had its closest relationship with DXR from Coffea arabica and Gardenia jasminoides. The subcellular localization revealed that MoDXR protein was located on the chloroplast. Plantcare analysis indicated that the promoter region sequence of MoDXR was 1 493 bp, covering multiple light, stress, and hormone-responsive cis-regulatory elements; protein electrophoresis showed that the expressed protein was the anticipated size. This research lays the foundation for further purification and structural and functional characterization of the MoDXR protein.
The chemical constituents of Rehmanniae Radix Preparata were prepared according to the traditional method of "jiu zheng jiu shai" and investigated using multiple chromatographic methods. Six alkaloids were isolated and their structures were elucidated from spectral data and physicochemical properties, as follows:rehmanniae alkaloid A (4-{[(5-O-á-D-galactopyranosyloxy)methyl]-1H-pyrrole-2-carbaldehyde-1-yl}butyric acidmethyl ester) (1), baimantuoluoamide B (2), capparisine C (3), harman-3-carboxylic acid (4), (2S)-1-[2-(furan-2-yl)-2-oxoethyl]-5-oxopyrrolidine-2-carboxylate (5), and 1-[2-(furan-2-yl)-2-oxoethyl]pyrrolidin-2-one (6). Among them, compound 1 is a new alkaloid. Compounds 2-6 were newly isolated from Rehmannia glutinosa Libosch. The effect of compounds 1-6 on NRK-52e cell injury induced by LPS was investigated. The results show that compounds 1-3 exhibit protective effects against LPS-induced damage to NRK-52e cells.
Oral transmucosal drug delivery can be defined as the administration of drug through the oral mucosa to achieve systemic effects. It has the advantages of high bioavailability and rapid drug response. In this review, we introduce the physiology of oral mucosa, and analyze the factors affecting the pharmacokinetic properties of oral transmucosal drug delivery in detail, such as physiological barriers, different administration sites, physicochemical properties of drugs, dosage forms, and formulation strategies. In addition, we describe the methods to evaluate the pharmacokinetic properties of this delivery systems, including in vitro permeability studies, buccal absorption studies, in vivo pharmacokinetic studies and physiologically based pharmacokinetics (PBPK) modeling, which provide methods and reference for the development of oral transmucosal drug delivery systems.
Drug screening against Candida albicans has become more urgent due to the increasing incidence of infection and the development of drug-resistant strains. The microfluidic chip technique has shown great potential for high-throughput drug screening. In this study we developed a concentration gradient microfluidic chip platform for drug screening against Candida albicans. The generated concentration gradient on this platform was investigated qualitatively by monitoring the distribution of the fluorescent tracer fluorescein sodium and quantitatively by following the distribution of the model drug fluconazole as analyzed by HPLC; the effect of different flow conditions on the concentration gradient were determined. The ratio of the two aqueous phase flow rates was determined in the subsequent drug screening studies. Alamar Blue, an indicator of cell viability, was used in the susceptibility test for amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, terbinafine, 5-fluorocytosine and caspofungin as carried out on the established chip platform. The MIC range of the drugs, which was consistent with the MIC values of the CLSI-recommended standard, were obtained quickly and efficiently through the use of this platform, indicating that this new platform can quickly screen a series of antibacterial drugs in one run. In addition, the strain of Candida albicans we used showed resistance to terbinafine in our platform assay, consistent with the results of a 96-well plate assay, indicating that the platform can also be used for rapid screening of resistant strains.
Xiaoshuan Tongluo formula is effective in treating mental retardation and speech astringency caused by cerebral thrombosis, but its mechanism remains unclear. In this investigation, by collecting the chemical constituents from Xiaoshuan Tongluo formula and the targets related to stroke, we obtained 1 251 constituents from the formula and 10 drug targets related with stroke. We established 18 prediction models of compound-target interaction for 10 stroke-related targets, using molecular docking method and machine learning methods includes Naive Bayesian and recursive partitioning based on the input of molecular fingerprints and molecular descriptors. Using these models, we predicted the active chemical constituents from Xiaoshuan Tongluo formula and their drug targets, 153 potential active constituents were discovered, 22 among them could interact with at least two drug targets related with stroke. On this basis, the chemical constituent-target network was constructed using network construction software, and then the important metabolic pathways of the targets were identified by using Gene-Ontology (GO) enrichment analysis, such as blood coagulation, positive regulation of angiogenesis, positive regulation of ion transport and so on. On this basis, a target-pathway network was constructed. In conclusion, using machine learning, molecular docking, virtual screening, data mining and network construction, this study explored and partially revealed the active chemical constituents and chemical constituent-target-pathway network action mechanism of Xiaoshuan Tongluo formula against stroke, which will provide important information for its further study.
There is no specific drug that has been approved for 2019-nCoV. There are a number of factors that pose major challenges in their development. Approaches to the development of anti-2019-nCoV include screening existing broad-spectrum antiviral drugs, repositioning of readily available clinical compounds, and de novo development of novel and specific agents for 2019-nCoV. Candidate compounds can be developed either to inhibit virus-based targets, such as RNA proteases, polymerase, spike glycoproteins, and viral envelop and membrane proteins, or to inhibit host-based targets, such as receptors and proteases that are utilized by virus for viral entry and endocytosis. Recently, the RNA polymerase remdesivir had demonstrated clinical efficacy in one patient with severe novel coronavirus pneumonia (NCP). The broad-spectrum viral protease inhibitor Kaletra® is also recommended in the current NCP clinical practice. Both drugs had lately been proceeded into multiple controlled phase Ⅲ clinical trials to test their safety and efficacy in NCP. Combinational therapies consisting of multiple drugs provide other viable options against 2019-nCoV, based on scientific and clinical rationales. Using bioinformatics and database analysis, we have identified 75 clinically compounds, including 20 marketed compounds, that are efficacious in inhibiting key targets in virus- and host-based approaches, which may facilitate the development of new therapeutic options for 2019-nCoV.
Neuropathic pain (NP), as a kind of chronic pain syndrome, seriously endangers the quality of life of patients, and the pathogenesis is complex, clinical treatment is limited, and it is easy to relapse. More and more reports have found that Wnt signaling pathway is closely related to the occurrence and development of neuropathic pain. Therefore, further study of the Wnt signaling pathway may provide useful ideas for exploring the pathogenesis of NP and discovering effective treatment methods. This article reviews the role and mechanism of Wnt signaling pathway in neuropathic pain.
Hepatic selective insulin resistance refers to that insulin fails to suppress hepatic glucose production but continues to promote hepatic lipogenesis in insulin resistance. Therefore, type 2 diabetes mellitus is characterized with dyslipidemia apart from hyperglycemia. This review highlights the roles and molecular mechanisms of the key hepatic lipogenesis factors such as sterol regulatory factor binding protein 1c (SREBP1c), mammalian rapamycin target complex 1 (mTORC1), endoplasmic reticulum stress (ER stress), FoxO1, lipid synthesis substrate, etc.
This work investigates the effects of Guilingji (GLJ) on D-galactose-induced aging and changes in serum metabolites by UHPLC-Q exactive orbitrap-MS in rats. The rat model of aging by subcutaneous injection of D-galactose (300 mg·kg-1) was used to analyze the effect of different concentrations of GLJ (37.5, 75, 150 mg·kg-1) on an open field test in aging rats. Rat serum was collected after 8 weeks and subjected to LC-MS to analyze the anti-aging effect of GLJ. Animal experimentation was approved according to the Committee on the Ethics of Animal Experiments of Shanxi University (SXULL2014032). GLJ significantly improved the autonomous activity of rats. Compared with the control group, 23 metabolites in the treated group changed significantly, involving three main pathways. The group that was given GLJ had altered regulation of 4 serum metabolites in two pathways. Our results indicate that GLJ can delay aging behavior in rats; the mechanism of this anti-ageing effect remains to be determined.
To study the mechanism of Huangqin decoction (HQT) in the treatment of ulcerative colitis (UC) by using network pharmacology, chemical components and targets related to the four herbs of Chinese meteria medical in HQT were searched through the traditional Chinese medicine systems pharmacology database and analysis platform (TCMSP) to construct the interaction network diagram of the target point of the compounds. The UC-related targets were screened through OMIM, TTD, and GeneCard databases. The compound-target network was constructed using Cytoseape_v3.7.1 software; based on the STRING database, a target interaction network for HQT for UC was constructed, and the core target of HQT for UC was selected based on topological parameters. GO (gene ontology) biological process enrichment analysis and KEGG (KEGG pathway analysis) pathway annotation analysis were performed on the disease and drug intersection targets using the R package clusterprofile version 3.12.0 in Bioconductor. The HQT compound-UC target network contains 128 compounds and corresponding targets 141. The core targets are AKTI, IL6, PTGS2, IL10, IL1β and so on. GO functional enrichment analysis yielded 151 GO terms, and KEGG pathway enrichment screening resulted in 33 associations with UC, mainly involving PI3K-AKT signaling pathway, NF-kappa B signaling pathway, TNF signaling pathway, Toll-like receptor signaling pathway and so on. The synergetic effect of HQT with multi-components and multi-pathway was confirmed by network pharmacology, and the main possible mechanism of HQT in treating UC was predicted, which lay a foundation for the identification of effective components, the mechanism of action, and clinical application.