Latest ArticlesAn UHPLC-Q-exactive orbitrap MS method for the simultaneous determination of 19 chemical components in Qilong Zhuang'er oral liquid was established and the quality differences between different batches of samples was compared by chemometric analysis to provide a basis for the quality evaluation of the preparation. The contents of allantoin, L-proline, pyroglutamic acid, hordenine, adenosine, L-phenylalanine, guanosine, L-tryptophan, caffeic acid, calycosin-7-glucoside, verbascoside, isoacteoside, ononin, calycosin, 3-hydroxy-9, 10-dimethoxyptercarpan, formononetin, atractylenolide Ⅲ, atractylenolide Ⅱ and astragaloside A were analyzed by cluster heat map, principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) using Hiplot platform and MarkerlynxXS software to comprehensively evaluate the quality difference of different batches of Qilong Zhuang'er oral liquid. The 19 chemical compounds showed good linearity in their respective concentration ranges (r ≥ 0.999). The RSD of precision, repeatability and stability (24 h) tests were all less than 1.94%. The average recovery was 97.24%-102.75% (RSD < 2.74%, n = 6). The 10 batches of samples were divided into two categories by cluster heat map and PCA analysis. 3-Hydroxy-9, 10-dimethoxyptercarpan, atractylenolide Ⅲ, calycosin, atractylenolide Ⅱ, formononetin, allantoin and caffeic acid were identified as differential markers by PLS-DA. The established multi component quantitative method of Qilong Zhuang'er oral liquid combined with chemometric analysis can provide reference for the quality evaluation of the preparation.
Rheumatoid arthritis (RA) is an autoimmune disease driven by antigens and mediated by T cells. Collagen II (CII) and fibrinogen (Fib) are the two main antigens in the pathogenesis of RA. The antigen produced after citrulline modification (Cit) is also one of the inducements to induce the body to produce a pathogenic anti-citrulline protein antibody (ACPA). To provide a reference for RA-related research, this study intends to establish an RA animal model by using CII, Cit-CII, Fib, and Cit-Fib antigens, emulsification with complete Freund's adjuvant and immunization with DBA/1 mice, respectively, to compare the pathological characteristics of RA models induced by different antigens from the aspects of pathology, imaging and serum biochemistry. Animal welfare and experimental process are in accordance with the regulations of the Experimental Animal Ethics Committee of the China Academy of Chinese Medical Sciences. The results showed that the CII, Cit-CII, and Cit-Fib induced mice all had symptoms such as joint redness and swelling, and toe deformation and the clinical score and incidence rate were higher than those of the normal group. The CII group had the most serious lesions, with a incidence rate of 100%, and the Cit-CII and Cit-Fib groups had mild symptoms, with a incidence rate of 25% and 37.5%, respectively; pathological and imaging examination results showed that the joints of mice in CII-induced group showed severe synovial inflammation, cartilage and bone destruction, while those in Cit-CII and Cit-Fib group showed only slight inflammatory infiltration, joint cavity stenosis and bone destruction; the results of serum antibody detection showed that CII, Cit-CII and Cit-Fib groups all produced high levels of anti-cyclic citrullinated peptide (CCP) antibodies, among which, Cit-Fib group > Cit-CII group > CII group > Fib group, and both Cit-CII and Cit-Fib groups produced high levels of citrullinated epitope-specific antibodies, while the total IgG level was the highest in CII group; serum ELISA and RT-PCR analysis of joint tissue showed that the expression of pro-inflammatory factors and bone destruction-related molecules increased most significantly in the CII-induced group, followed by Cit-Fib and Cit-CII. The above results showed that among the four different antigens, the symptoms and conditions of arthritis in RA mice induced by CII were the most serious, and IgG instead of anti-CCP antibody was its typical immunological feature, and CII could be the first choice for the model of RA mice; Cit-Fib has certain immunogenicity, can partially induce the symptoms and conditions of RA arthritis in mice, and produce high-level anti-CCP antibody and anti-Cit-Fib antibody, which is more suitable for the study of citrulline-related RA; although Cit-CII has certain immunogenicity, the incidence, and severity of RA arthritis induced by Cit-CII in mice are low.
Two new ursane triterpenoids along with twelve known compounds were isolated from 80% ethanol extract of Agastache rugosa (Fisch. et. Mey.) O. Kuntze by using silica gel column, MCI column, ODS column and HPLC. The structures of the new compounds were identified as 2α, 3α-dihydroxy-24-nor-urs-4(23), 12(13)-dien-28-oic acid (1) and 2α, 3α-dihydroxy-24-nor-urs-4(23), 12(13), 20(30) -trien-28-oic acid (2) by HR-ESI-MS, NMR and ECD spectral data, named agasursacid A and agasursacid B. In addition, compounds 3, 4, 6, 8 showed anti-coxsackievirus B3 (CVB3) activities with a IC50 as 4.77, 1.59, 11.11 and 25.87 μmol·L-1, resepectively.
As an edible eukaryotic microorganism, Saccharomyces cerevisiae has the characteristics of high safety, rapid proliferation, low cost, easy transformation, etc. It has been widely used to produce vaccines, antibodies, insulin, etc. Up to now, yeast components, such as cell wall and yeast microcapsules, have been widely used in the treatment of tumors, inflammatory virus infection, post-traumatic osteoarthritis and other diseases. Among them, the components of yeast cell membrane are relatively simple and stable, which are easy to be extracted on a large scale. Therefore, yeast cell membrane material was used to construct yeast membrane vesicle nanosystem, and its biomedical application was preliminarily explored. In this study, Saccharomyces cerevisiae membrane vesicle (SMV) was prepared by co-extrusion method, and the particle size and surface potential of SMV, drug loading and release characteristics, stability, cell safety, and in vitro therapeutic effect were investigated. The results showed that the average particle size of SMV was 185.1 nm. Curcumin and silica nanoparticles were effectively encapsulated by co-incubation and ultrasonic methods, and the characteristics of cell membrane proteins were maintained. Moreover, SMV had good stability and biocompatibility. In addition, SMV could be effectively uptaken by macrophages RAW 264.7, and curcumin loaded SMV could effectively eliminate reactive oxygen species (ROS). In conclusion, the yeast plasma membrane vesicles prepared in this study could effectively deliver curcumin drugs and encapsulate nanoparticles, and could be effectively absorbed by macrophages and effectively eliminate ROS, providing new ideas and new methods for biomedical applications of yeast membrane materials.
The purpose of this study is to investigate the effect of Reduning injection (RI) on influenza A virus (IAV) and its mechanism. We evaluated the cytotoxicity of RI in A549 and MDCK cells by cell counting kit-8 (CCK-8) assay. Western blot and cytopathic effect (CPE) assays were applied to test the effects of RI on viral protein, CPE and virus virulence to evaluate its inhibitory effect. The proteins level of heme oxygenase 1 (HO-1), nuclear factor erythroid 2-related factor 2 (Nrf2), phosphorylation of P38 mitogen-activated protein kinases (MAPK) and extracellular signal-regulated kinases 1/2 (ERK1/2) were detected by Western blot. Real-time fluorescence quantitative PCR (qRT-PCR) was used to detect the RNA expression of interferon-α/β (IFN-α/β). The relative luciferase reporter assay was used to analyze the promoter activity and transcriptional regulation of Nrf2. The results indicated that RI inhibited IAV-induced MDCK cytopathies in a dose-dependent manner, decreased M2 protein of influenza virus and viral titer, indicating that it has definite effect on inhibiting IAV. RI promotes the phosphorylation of P38 MAPK and ERK1/2, activates the activity of Nrf2 nuclear transcription factor, increases the expression of Nrf2 protein in the nucleus, thus up-regulates the expression of HO-1 protein, and ultimately increases the IFN-α/β mRNA level. In summary, our results demonstrated that RI inhibits the replication of IAV by activating MAPK/Nrf2/HO-1 signaling pathway, revealing a new mechanism of RI against influenza virus, and providing theoretical basis for clinical treatment of influenza virus.
Antibody-drug conjugate (ADC) has the characteristics of low toxicity and high efficiency, and plays an important role in cancer treatment. However, due to the complexity of its structure, it brings difficulties in pharmacokinetic (PK) bioanalysis. This study established an analytical method for the detection of ADC (RC108) in cynomolgus monkey plasma by ligand-binding assay (LBA) and liquid chromatography tandem mass spectrometry (LC-MS/MS), which was used to analyze and quantify the total antibody, bound antibody and free drug in cynomolgus monkey plasma. Based on the LBA method, rabbit anti-RC108 Fab and mouse anti-MMAE (monomethyl auristatin E) mAb were pre-coated in 96-well plates as the total antibody and antibody binding reagents, respectively. The samples to be tested were added, and then the detection reagents were added in turn. Goat anti-human IgG (H+L)-HRP, chromogenic solution tetramethylbenzidine (TMB), H2SO4 terminate the reaction, read data at 450 nm/630 nm wavelength of microplate reader; LC-MS/MS analysis method quantifies MMAE concentration, and refer to relevant regulations for methodological validation. The analytical method for quantifying total antibody, bound antibody and free drug of RC108 drug obtained good accuracy and precision, and the selectivity, dilution linearity, hook effect, parallelism and stability were verified. Meet the requirements of biological analysis. Finally, a bioanalytical method for the determination of the concentration of the test substance RC108 (total antibody, conjugated antibody, free MMAE) in cynomolgus monkey plasma with high sensitivity and high throughput was established by LBA and LC-MS/MS method. Subsequent non-clinical research on PK research in cynomolgus monkeys will provide technical support.
COVID-19 epidemic continues to spread around the world till these days, and it is urgent to develop more safe and effective new drugs. Due to the limited P3 biosafety laboratories for directly screening inhibitors of virulent viruses with high infectivity, it is necessary to develop rapid and efficient screening methods for viral proteases and other related targets. The main protease (Mpro), which plays a key role in the replication cycle of SARS-CoV-2, is highly conserved and has no homologous proteases in humans, making it an ideal target for drug development. From two different levels, namely, molecular level and cellular level, this paper summarizes the reported screening methods of SARS-CoV-2 Mpro inhibitors through a variety of representative examples, expecting to provide references for further development of SARS-CoV-2 Mpro inhibitors.
We constructed and optimized the plasmid DNA (pDNA) Opt-S encoding the gene of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) protein, using poly (lactic-co-glycolic acid) copolymer (PLGA) as a delivery carrier for pDNA. PLGA-pDNA NPs were loaded by nanoprecipitation and its properties in vitro were preliminary evaluated. The results showed that the prepared PLGA-pDNA NPs were regular morphology, clear edges, with an average particle size of (184.2 ± 2.4) nm, polydisperse index (PDI) of 0.093 ± 0.013, zeta potential of (-68.10 ± 0.36) mV, and encapsulation rate of (98.92 ± 0.22)%. The PLGA-pDNA NPs were stable at -20 ℃ for 7 months and could protect pDNA against nuclease degradation. And they also exhibited sustained release of pDNA in vitro. The PLGA-pDNA NPs have low cytotoxicity and high safety. In addition, in vitro transfection experiments showed that the SARS-CoV-2 S gene could enter cells and be expressed. These results indicate that PLGA-pDNA NPs non-viral gene vector have simple preparation process and good performance, which are expected to provide a new idea for the research and development of SARS-CoV-2 vaccine.
A variety of full 2ʹ-F/OMe-modified siRNAs were designed and synthesized, and the activity against hepatocellular carcinoma Huh-7 and HepG2 cells was evaluated. K&A DNA/RNA H-8 synthesizer was used to synthesize siRNAs, and neutral cytidinyl lipid DNCA mixed with cationic lipid CLD were used to transfect siRNA. By RT-qPCR and CCK-8 assay, the target gene silence and the proliferation of Huh-7 and HepG2 cells were detected. The siRNAs loading into Ago2 protein was detected by RNA-binding protein immunoprecipitation. Drug uptake and cell apoptosis were detected by flow cytometry, and the expression of PLK1 protein was detected by Western blot. Partial full 2ʹ-F/OMe modified siRNAs, especial siPLK1A3, increased the uptake of Huh-7 cells, enhanced their binding to Ago2 and gene silencing activity, down-regulated PLK1 protein, as well as induced more Huh-7 cell apoptosis and proliferation inhibition activity. It provides important data for the development of novel siRNA modification patterns and anti-HCC formulations.
As a member of G protein coupled-receptors superfamily, free fatty acid receptor 1 (FFAR1), is also known as GPR40, has been shown to regulate numerous pathophysiological processes in a variety of tissues and organs. The activated FFAR1 has a variety of biological functions. For instance, it can not only regulate metabolism of fatty acids and glucose, but also play an important role in immune inflammatory response, it may be a potential drug target for the treatment of various chronic inflammatory diseases. In this review, we focus on the recent researches of FFAR1's action in the regulation of pathophysiological processes, its molecular mechanism and new agonists development. At the same time, this review will take the discovery of series FFAR1 agonists as examples, and display the applied prospects of FFAR1.