Latest ArticlesC17 is a small molecule containing 2, 4-diaminoquinazoline and aryl piperazine. Docking was used to compare the affinity of C17 for five dopamine receptor (DR) subtypes. Pancreatic cancer SW1990 and PANC-1 cell lines were used in in vitro and in vivo studies. The effect of C17 on the expression level of D1DR was investigated by immunofluorescence. A cytotoxicity assay, clone formation assay and flow cytometry were used to investigate the ability of C17 to inhibit on cell survival, clone formation, and to suppress cancer stem-like cells (CSCs). The ability to suppress tumorigenesis was investigated by inoculating nude mice with SW1990 cells pre-treated with different concentrations of C17. Finally, the anti-tumor efficacy and safety of C17 and its combination with the multitarget tyrosine kinase inhibitor sunitinib (SUN) were evaluated in SW1990 xenograft mice. Our results demonstrate that C17 is most likely to bind to D1DR among the five DR subtypes. D1DR expression was increased in C17-treated cells, which could be reversed by SCH23390, a D1DR-specific antagonist. The IC50 values of C17 on the survival of SW1990 and PANC-1 cells were 12.56 and 10.56 μmol·L-1, respectively. C17 could suppress clone formation ability, CSC frequency and in vivo tumorigenesis in a dose-dependent manner. In the SW1990 xenograft model, 50 mg·kg-1 of C17 could weakly inhibit the tumor growth, and the tumor volume with 50 mg·kg-1 of C17 in combination with 10 mg·kg-1 of SUN group was smaller than that in SUN 10 mg·kg-1, SUN 20 mg·kg-1 group and gemcitabine (GEM) group. In addition, body weight, blood test, and organ index results showed good safety with all dosing regimens. All animal experiments were in strict accordance with the regulations of the Biomedical Ethics Committee of Peking University. C17 may be a promising candidate for the treatment of pancreatic cancer.
We investigated the ability of 3-bromopyruvic acid to increase the sensitivity of tamoxifen-resistant MCF-7/TR cells to tamoxifen and to explore the underlying mechanism. 4-Hydroxy tamoxifen (4-OHT) is the active form of tamoxifen in vivo and was used in this study. The effect of 3-bromopyruvic acid on the viability of MCF-7/TR cells was measured by MTT assay and the morphology of MCF-7/TR cells was observed with an inverted microscope. The results show that 3-bromopyruvic acid at 40 μmol·L-1 has no significant effect on the viability of MCF-7/TR cells, and this concentration was used in the subsequent experiments:3-bromopyruvic acid significantly increased the inhibitory effect of 4-OHT on the viability of MCF-7/TR cells, with a reversal-fold of 1.91, as determined by MTT assay; the lactate level, determined with a lactate detection kit, and the expression levels of GLUT1, HK2, and LDHA in MCF-7/TR cells as measured by immunoblotting were significantly higher than in MCF-7 cells; and compared with 4-OHT treatment alone, the combination treatment of 3-bromopyruvic acid and 4-OHT significantly reduced the lactate level and the expression of GLUT1, HK2, LDHA in MCF-7/TR cells. The above results show that 3-bromopyruvic acid increases the sensitivity of MCF-7/TR cells to tamoxifen, and the mechanism is related to the inhibition of aerobic glycolysis.
This study was designed to investigate the effect and mechanism of astragaloside IV (ASIV) on mitochondrial morphology and function of rat cardiomyocytes under hypoxia/reoxygenation injury. H9c2 cells were divided into control group, hypoxia/reoxygenation (H/R) group, and H/R + ASIV group. Cell viability and lactate dehydrogenase (LDH) leakage were measured by cell counting kit-8 (CCK-8) and LDH assay kit, respectively. Oxidative stress levels, such as superoxide dismutase (SOD), glutathione (GSH), and malondialdehyde (MDA), were analyzed by commercial kits. Intracellular and mitochondrial reactive oxygen species (ROS) levels were detected by dihydroethidium (DHE) and MitoSOX. Changes of the mitochondrial membrane potential were detected using the fluorescent probe JC-1. Opening of mitochondrial permeability transition pore was examined via calcein acetoxymethyl ester (calcein-AM). Apoptosis was assessed using terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) assay kit. To detect protein expression of dynamin-related protein 1 (Drp1), mitofusin1 (Mfn1), Mfn2, Bax, B-cell lymphoma-2 (Bcl-2), and cleaved cysteine-aspartic protease (caspase)-3, Western blot analysis was carried out. Compared with the control group, ASIV (100 μmol·L-1) significantly improved H/R induced cell injury, LDH leakage, decrease of SOD activity, and GSH content, increase of MDA content and ROS content, loss of mitochondrial membrane potential, mitochondrial permeability transition pore opening, ROS production activation, mitochondrial fission/fusion imbalance, and cell apoptosis. In addition, the effect of ASIV against H/R injury was also verified on primary rat cardiomyocytes. The animal welfare and experimental process follow the rules of Animal Ethics Committee of Zhejiang Chinese Medical University. In conclusion, ASIV may play a protective role in mitochondria by regulating morphological dynamic stability and mitochondrial function, inhibiting excessive synthesis of ROS, improving the internal environment of oxidative stress, reducing cell apoptosis, and thereby protecting against cardiomyocytes' hypoxia/reoxygenation injury.
Epithelial cell adhesion molecule (EpCAM) is a popular target for cancer therapy. In this research, 3 nanobodies with high specificity and endocytosis activity against EpCAM were developed, which provides a basis for the study of immunotoxin based on EpCAM. In our preliminary experiments, we have immunized a camel with EpCAM-Fc antigen and constructed a high-quality phage display library. Seventeen nanobodies with different complementarity determining region (CDR) 3 sequences have been screened after 3 rounds of biopanning by phage display technology. The animal procedures were approved by the Institutional Animal Care and Use Committee (IACUC) of Fudan University School of Pharmacy. After purification, 7 nanobodies showed high cell binding activity by fluorescent activated cell sorting (FACS) identification. Furthermore, 3 nanobodies presented high endocytosis activity based on FACS and laser confocal microscopy, which also showed high affinity to EpCAM measured by ForteBio. According to this study, we aimed to provide a novel alternative approach to the EpCAM-targeted therapy and to provide guidance for the study of nanobody based immunotoxins for other targets.
Asthma is a chronic inflammatory disease involving eosinophils, mast cells, lymphocytes, neutrophils and other inflammatory cells and immune components. Chinese medicine has unique advantages in the treatment of asthma. In this study an ovalbumin (OVA)-induced asthma model in rats was used to verify the effect of the total sesquiterpenoids of Flos Farfarae (F.F.S) on asthma. The results show that the F.F.S has anti-asthmatic effects. Metabolomic analysis showed that 25 metabolites were changed in asthmatic rats, and 18 of them could be attributed to F.F.S. F.F.S. can block the over-activation of p65 NF-κB, preventing the transmission of pro-inflammatory factor signals to cells. F.F.S. thus could reduce the over-activation of inflammatory cells, inhibiting the secretion of inflammatory factors and further alleviating asthma inflammation. This study lays a foundation for further new drug research. The mechanism of F.F.S. on asthma needs further investigation.
We separated and purified five chemical constituents of dried ginger by Diaion HP-20, Sephadex LH-20, silica gel and semi-preparative high performance liquid chromatography. Five gingerols were identified by physicochemical properties and MS and NMR spectroscopy techniques:4-(2-butyl-6-methyl-4H-pyran-4-yl)-2-methoxyphenol (1), 4-(2-hexyl-6-methyl-4H-pyran-4-yl)-2-methoxyphenol (2), 1-(4-hydroxy-3-methoxyphenyl)tridecane-3, 5-diol (3), [10]-gingerdiol (4) and 1-[1-(4-hydroxy-3-methoxy phenyl)-3-oxodecan-5-yl]pyrrolidin-2-one (5a, 5b). Compounds 1-3, 5a, 5b are new compounds.
Tumor immune therapy has been remarkably successful in recent years and several kinds of PD-1/PD-L1 (programmed death-1/programmed death-ligand 1) antibody drugs have been approved by the FDA for treatment of advanced malignant neoplasms. However, as biomacromolecules these antibody drugs have certain drawbacks such as high cost, injection-only administration and immunogenicity; thus, we turned to small molecules that have lower immune risks and better modifiability. Considering the structural diversity of natural products, we chose to investigate the active components in Panax ginseng, a famous and highly valued traditional Chinese medicine. Nine compounds were separated and identified in this research using a HPLC-coupled MS system, and 3 PD-1 binding compounds were identified using the SPR method. The PD-1/PD-L1 inhibitory ability of ginsenoside Rg1, as a representative ginsenoside, was verified by cytopharmacological methods. This research provides a new method for the identification of immune blockade inhibitors in natural products.
We utilized a multi-step derivatization gas chromatography-mass spectrometry method for the determination of common amino acid enantiomers, combined with deuterated hydrochloric acid hydrolysis, to identify nine trace D-amino acids in thymalfasin. We optimized the conditions for multi-step derivatization, the volume of reagent for redissolving samples, and the conditions for chromatography and mass spectrometry with isopropanol and trifluoroacetic anhydride as derivatization reagents, and validated the procedure, including sensitivity, linear range, precision, accuracy and recovery. Sixteen pairs of D/L-amino acids and glycine derivatives were separated within 29 min, with the limit of quantification as low as 0.09-2.79 μmol·L-1. Nine amino acid derivatives of thymalfasin showed a good linear relationship within the concentration range examined (r2>0.992 3). The precision results showed that RSD values were less than 10.90%. Accuracy test results of a reference substance ranged from 76.69% to 128.18%. Average recoveries of spiked samples ranged from 70.41% to 125.39%. For the nine D-amino acids assayed, D-Asp and D-Glu content in six batches of thymalfasin were highest, ranging 0.41%-0.49% and 0.25%-0.33%, respectively, with others less than 0.25%. The method is sensitive, efficient and reliable, available for seventeen common amino acids and their enantiomers, and works well with simultaneous determination of nine trace D-amino acids in thymalfasin, providing a reference for the comprehensive control of racemic peptide impurities in this synthetic polypeptide drug.
To establish a method for the determination of polymer impurities in cefixime raw materials and preparations, a cefixime degradation solution containing polymer impurities was prepared by forced polymerization. Polymer impurities in the degradation solution were separated and identified by high performance gel chromatography and the column switching-LC-MSn method. A new RP-HPLC method for cefixime polymer was established and validated with a Phenomenex Gemini-C18 column using a mobile phase gradient elution of 0.5% formic acid-water solution and 0.5% formic acid-acetonitrile solution. The results showed that when using this high performance gel chromatography method some small molecular weight impurities were co-eluted with the polymers, resulting in a poor specificity and poor quantitative accuracy. But when using the RP-HPLC method, three polymer impurities were detected with good specificity, sensitivity and robustness, including two cefixime dimers, and dehydrate dimer. Therefore, the described RP-HPLC method is suitable for the quality control of polymer impurities in cefixime, and cefixime degradation solution can be used as suitable solution for analysis of cefixime polymers.
A high performance liquid chromatography charged aerosol detector (HPLC-CAD) method was established for the simultaneous determination of five saponins (notoginsenoside R1, ginsenoside Rg1, ginsenoside Re, ginsenoside Rb1, Ginsenoside Rd) in Yaobitong capsule, providing a method for quality control. The sample was extracted with methanol and chromatographic separation was performed on a Waters Xbridge Phenol column (150 mm×4.6 mm, 3.5 μm) using acetonitrile-water as the mobile phase with gradient elution at a flow rate of 1.0 mL·min-1. The column temperature was 30℃ and the injection volume was 10 μL. The nebulizer temperature of CAD was 35℃ and the air pressure was 60.2 psi, the filtration was 3.6 s, and the collection frequency was 5 Hz. Notoginsenoside R1, ginsenoside Rg1, ginsenoside Re, ginsenoside Rb1 and ginsenoside Rd showed a good linear relationship in the range of 16.96-203.5 μg·mL-1 (R2=0.999 3), 54.46-653.5 μg·mL-1 (R2=0.999 3), 10.96-131.5 μg·mL-1 (R2=0.999 6), 51.50-618.0 μg·mL-1 (R2=0.999 0), 15.94-191.3 μg·mL-1 (R2=0.999 4), respectively. The average recoveries were 98.96%, 100.8%, 94.76%, 100.1%, 103.1%, and RSDs were 0.87%, 1.46%, 1.85%, 2.06%, 0.96% (n=6), respectively. The proposed method is accurate, simple and reliable, and can be used for the determination of five saponins in Yaobitong capsule.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62662699(Operation and Technical Support)
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
