Latest ArticlesBased on the idea of multi-target drug design, taking p-aminosalicylic acid (PAS) as the parent nucleus, the unreported target molecules TM1 and TM2 were designed with PAS, isonicotinic acid and fluoroquinolone as three structural units conjugated by different linkers. Sixteen target molecules were synthesized by multi-step reaction, and their activities against Mycobacterium tuberculosis and human pathogenic bacteria were evaluated. The results showed that the anti-tuberculosis activity of TM2a was stronger than those of the assayed fluoroquinolones, while TM1a was comparable to that of clinafloxacin, the most active compound of the positive control fluoroquinolones; TM1a showed the strongest inhibitory activity to all almost tested strains, TM1b and TM2a showed very strong inhibitory activity to most strains, and TM1h/2h had strong inhibitory activity to some strains; The inhibitory activities of TM1a/1h on Staphylococcus aureus ATCC14125 are much stronger than those of fluoroquinolones, which eminently deserves further study. The hemolysis test results showed that the highly active molecules TM1a and TM2a exhibited relative safety below the concentrations of 8 and 32 μg·mL-1, respectively. In this study, a new hybrid molecule of three molecular pharmacophores with PAS as the parent nucleus was synthesized for the first time, and some of which have highly strong antibacterial activity, which provides a new idea for the research and development of antibiotics.
The quality control and evaluation methods of Schizonepeta tenuifolia were established by HPLC fingerprint, multi index component content determination and chemical pattern recognition to provide basis for the quality control of medicinal materials. The chemical components of 25 batches of Schizonepeta tenuifolia panicle medicinal materials and decoction pieces collected were analyzed by high performance liquid chromatography, and the common pattern of fingerprint was established. A total of 22 common chromatographic peaks were calibrated, and their similarity was more than 0.9. The samples were divided into three categories according to different producing areas by cluster analysis. The results of principal component analysis and cluster analysis were consistent. Finally, five differential markers of different batches of Schizonepeta tenuifolia were selected by orthogonal partial least squares discriminant analysis. Through the identification of the reference substance, it was determined that peak 9 was hesperidin, peak 10 was rosmarinic acid, peak 13 was tilianin, peak 14 was quercetin, and peak 20 was pulegone. The quality evaluation method established in this study is stable and reliable, and is suitable for the quality control of Schizonepeta tenuifolia.
Local drug delivery is a new strategy to prevent postoperative recurrence of cancer, thermosensitive gel is a typical topical drug delivery system. In this study, a novel paclitaxel thermosensitive gel (PTG) was prepared to prevent recurrence after chemotherapy for cancer, the effects of drug particle size on release and absorption rate in vivo were investigated. Paclitaxel suspensions with different particle sizes were prepared by medium grinding, high pressure homogenization, air crushing and screening. Using poloxamer as the gel matrix and carbomer as the biological adhesive, Box-Behnen was used to optimize the formulation of PTG. The morphology, viscosity, rheological properties and biological adhesion of thermosensitive gel were characterized. The relationship between dissolution and release of thermosensitive gel was investigated by weight loss method, pharmacokinetics was studied in rats. The paclitaxel suspensions with the particle sizes of 350 nm, 800 nm, 3 μm and 9 μm were prepared, 19% poloxamer 407, 4% poloxamer 188 and 0.1% carbomer were used to prepare PTG. The phase transition temperature of thermosensitive gel was 30 to 35 ℃, there was a good linear relationship between in vitro release and gel dissolution. In the pharmacokinetic study, area under the curve (AUC0-t) increased with the decrease of particle size. In general, the PTG prepared in this study can rapidly change into gel under human body temperature, provided with good adhesion. The release rate in vitro is closely related to the particle size, the release rate increased with the decrease of particle size. This study provides data support for preventing postoperative recurrence of cancer. The animal welfare and experimental process in this paper follow the regulations of the Animal Ethics Committee of the Academy of Military Medical Sciences.
For quantitative analysis of related substances in TSD-1 active pharmaceutical ingredient, structures of prepared impurities were confirmed by NMR and UHPLC-MS, and a high performance liquid chromatographic method was established to determine the related substances in TSD-1. The analytical column was an Agilent ZORBAX Eclipe XDB-C8 (250 mm × 4.6 mm, 5 µm). The mobile phase A was 50 mmol·L-1 ammonium acetate solution (adjusted pH to 5.8 with acetic acid) and the mobile phase B was acetonitrile. The whole run was carried out by gradient elution at a flow rate of 1.0 mL·min-1. The detection wavelength was set at 240 nm and the column temperature was 30 ℃. The resolutions among peaks of TSD-1, impurity A, impurity B, TSD-D, and TSD-F were good. The calibration curves (n = 7) of TSD-1, impurity A, impurity B, TSD-D and TSD-F were linear in their respective weight ranges of 0.242-48.4 µg·mL-1 (r = 1.000 0), 0.244-9.75 µg·mL-1 (r = 0.999 9), 0.244-4.80 µg·mL-1 (r = 0.999 9), 0.254-1.02 µg·mL-1 (r = 0.999 9), and 0.247-0.987 µg·mL-1 (r = 0.999 9). The lower limits of quantitation were 0.244, 0.244, 0.254, and 0.247 µg·mL-1 for impurity A, impurity B, TSD-D, and TSD-F, respectively, and the average recovery of each impurity ranged from 99.08% to 103.00% with high accuracy. TSD-D and TSD-F were not detected in the three batches of TSD-1 active pharmaceutical ingredients, and impurity A and impurity B were not detected beyond the limit. The established HPLC method is simple, accurate, and suitable for determination of related substances of TSD-1, which can provide a valuable reference for the subsequent development of TSD-1.
The COVID-19 outbreak has drawn attention to viral infectious diseases once again, and the development of antiviral drugs for both known and potentially emerging viruses is of great significance. In recent years, peptides and protein drugs are becoming a hot spot in the field of antiviral drug research and development. Phage display technology, as a powerful tool for screening peptides and protein drugs, has been increasingly concerned in the academic and industrial fields. The present review introduced the basic principle of phage display technology, summarized phage display libraries often used in antiviral drug discovery and their applications, discussed the challenges and future direction of antiviral drug research and development based on phage display technology.
Lu Dangshen is the geoherb in Shanxi Province. The content of Codonopsis pilosula polysaccharides (CPP) in Lu Dangshen is more than that in other Codonopsis Radix from other regions. Glycosyltransferase is the key enzyme for the synthesis of bioactive components, such as CPP and tangshenoside I. Based on the transcriptome data of C. pilosula [Codonopsis pilosula (Franch.) Nannf.] from different producing areas, this study carried out functional annotation of GO and KEGG, conservative domain analysis, phylogenetic tree analysis and expression pattern analysis of glycosyltransferase genes in C. pilosula to provides a theoretical basis for exploring the mechanism of genuineness formation in Lu Dangshen. In this study, 98 glycosyltransferase genes were screened and identified, which belonged to GT family 1, GT family 2, GT family 90 and other families. By GO functional annotation, it was found that most of the glycosyltransferase genes had catalytic activity. Analysis of KEGG functional annotation showed that C. pilosula glycosyltransferase was mainly involved in glycan organism and terpenoid and polyketone metabolism. Among them, conserved domain of 42 glycosyltransferase genes in GT family 1 was [X]-W-[2X]-Q-[3X]-[LH]-[5X]-[FLTHCGWNS]-[2X]-E-[4X]-[GVP]-[4X]-P-[4X]-Q-[2X]-[NAK]. Phylogenetic tree analysis based on the glycosyltransferase sequence in Arabidopsis thaliana showed that C. pilosula glycosyltransferases were mainly located in Arabidopsis thaliana UGT73, 72 and 85 branches. Gene expression pattern analysis showed that expression of CpUGT73AH2 was higher in Lu Dangshen than that in Baitiaodang and could respond to drought and low temperature stress. In conclusion, a glycosyltransferase gene CpUGT73AH2, which is involved in the metabolism of terpenoids and polyketides and can respond to environmental stress, was screened from the C. pilosula glycosyltransferase family 1, which was used to further study the role of C. pilosula glycosyltransferase in Lu Dangshen. It laid a theoretical foundation for further study on the role of C. pilosula glycosyltransferase in the formation of Lu Dangshen.
Cystic fibrosis (CF) is a common and life-threatening autosomal recessive disorder in Caucasians populations. The disease is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The absence of mature CFTR at the correct cellular location or dysfunction of CFTR proteins has been observed in CF patients. CF is frequently accompanied by a variety of complex complications, such as impairments in pulmonary functions, which may lead to successive infections and respiratory failure. Recently, with the understanding of the pathogenesis of CF, a wide array of therapeutic strategies for the treatment of CF has been designed. This review summarizes pathogenic mechanisms of CF, mechanisms of action of drugs, routes of administration, and new drug development as well as provides insights into the advanced treatment strategies for CF.
A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to determine the plasma concentration of progesterone in Beagle dogs, and apply it to the study of the pharmacokinetics of progesterone sustained-release formulation in Beagle dogs. The plasma samples were processed by protein precipitation method and megestrol acetate was used as an internal standard (IS). The quantitation analysis was performed using multiple-reaction monitoring (MRM) mode at the specific ion transitions of m/z 315.2→97.0 for progesterone and m/z 385.2→267.1 for megestrol acetate (IS) under the positive ion condition. Male Beagle dogs were injected intramuscularly with progesterone sustained-release microspheres and the plasma samples were collected at different time points after administration. The relevant pharmacokinetic parameters were calculated by WinNonlin 8.1 software. A good linearity over the range of 0.1-500.0 ng·mL-1 was yielded by this method. The intra- and inter-day precision (RSD) were all less than 13.25% and the accuracy (RE) was within 8.92%. Stability test showed that progesterone in dog plasma was stable at room temperature for 12 h, up to 60 days at -20 ℃ and after three cycles of freeze-thaw. The recovery of it ranged from 71.43%-77.97%. After intramuscular injection of progesterone sustained-release microspheres in Beagle dogs, tmax was 19.00 ± 25.36 h, Cmax was 137.72 ± 11.59 ng·mL-1, t1/2 was 83.83 ± 26.43 h. The drug was released continuously in vivo and in a continuous absorption process for many times with good sustained-release effect. The method developed in this study is sensitive, rapid and stable. It is suitable for the determination of progesterone plasma concentration in Beagle dogs, and can be applied to the preclinical pharmacokinetic study of progesterone-related formulations. The animal experiment scheme of this study was approved by the Animal Ethics Committee of the Academy of Military Medical Sciences.
We intend to study the structural characteristics of Lycopus europaeus Linn. chloroplast genome and compare the evolutionary relationship of species from Lamiaceae with similar medicinal effects. The total DNA of Lycopus europaeus was sequenced using the Illumina Hiseq 4000 Sequencing platform and was assembled using NOVOplasty software. And then we annotated and analyzed the genome using the CPGAVAS2 online tool. We constructed the phylogenetic tree using the Stellera chamaejasme and Potentilla chinensis as the outgroup. The whole length of Lycopus europaeus chloroplast genome was 152 085 bp. A total of 132 genes were annotated including 88 protein-coding genes, 8 rRNA genes and 36 tRNA genes. Among them, 8 protein-coding genes (ndhB, rps7, rps12, rps19, rpl2, rpl23, ycf2, ycf15), 7 tRNA coding genes (trnM-CAU, trnL CAA, trnN-GUU, trnE-UUC, trnV-GAC, trnA-UGC, trnR-ACG) and 4 rRNA coding genes (rrn16s, rrn23s, rrn4.5s, rrn5s) are located in the IR region. There are 13 protein coding genes [rps16, rps19 (×2), atpF, rpoC1, rpl2 (×2), petB, petD, rpl16, ndhB (×2), ndhA] each contains one intron, two protein-coding genes (ycf3, clpP) each contain two introns, and 8 tRNA coding genes each contain one intron. A total of 34 SSRs were detected in the chloroplast genome of Lycopus europaeus. Phylogenetic analysis revealed that two species in the Lycopus genus, four species in the Dracocephalum genus, Glechoma longituba, two species in the Mentha genus and Prunella vulgari, in total 10 species are most related. The complete genome sequence of Lycopus europaeus was obtained and analyzed, which clarified the evolutional relationship between the species of Lycopus europaeus and in the Lamiaceae family.
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.