Latest ArticlesActivity-based protein (proteomic) profiling (ABPP) has emerged as a key component of the broad field of chemical techniques capable of directly analyzing enzyme activity in living systems. With the deepening of research on electrophilic warheads and nucleophilic amino acids, and the continuous proposal and improvement of effective development strategies, the application of amino acid-targeting active probes in various biological systems has facilitated the identification, development of new targets in various disease contexts and discovery of inhibitors. The purpose of this review is to summarize the latest progress in the design and application of active probes targeting specific amino acids, in order to provide support for the further development of amino acid-targeted covalent inhibitordrugs.
Chirality is one of the fundamental properties of nature, and most of the important molecules in living organisms contain chiral structures. The efficacy and safety of drugs are often closely related to the chiral structure of compounds, however, there are relatively more studies on synthetic characterization, pharmacology, and toxicology of chiral small molecule chemical drugs, but relatively less studies on chiral compounds contained in natural drugs such as traditional Chinese medicines. Chiral separation, as the basis of chiral research, has a pivotal position in the study of chiral compounds. In this paper, we systematically describe the separation methods of chiral compounds from the classification of chiral splitting methods based on chromatographic and non-chromatographic methods, as well as chromatographic packing materials, chiral additives and chiral derivatization, and review the chiral compounds in natural drugs such as traditional Chinese medicines reported in the past ten years, in order to provide references for the splitting and evaluating the activity of chiral compounds, and the improvement of quality standards of traditional Chinese medicines.
In 2015, the United States put forward the concept of precision medicine, which changed medical treatment from "one size fits all" to personalization, and paid more attention to personalization and drug customization. In the same year, Spritam®, the world's first 3D printed tablet, was in the market, marking the emerging pharmaceutical 3D printing technology was recognized by regulatory authorities, and it also provided a new way for drug customization. 3D printing technology has strong interdisciplinary and high flexibility, which puts forward higher requirements for pharmaceutical staffs. With the development of artificial intelligence (AI), modern society can perform various tasks, such as disease diagnosis and robotic surgery, with superhuman speed and intelligence. As a major AI technology, machine learning (ML) has been widely used in many aspects of 3D printing drug, accelerating the research and development, production, and clinical application, and promoting the new process of global personalized medicine and industry 4.0. This paper introduces the basic concepts and main classifications of 3D printing drug, non-AI drug optimization technology and ML. It focuses on the analysis of the research progress of ML in 3D printing drug, and elucidates how AI can empower the intelligent level of 3D printing drug in pre-processing, printing, and post-processing process. It provides a new idea for accelerating the development of 3D printed drug.
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.
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.
Cannabinoid receptors are one of the most expressed G protein-coupled receptors in the central nervous system, which are potential drug targets for inflammation, pain and drug abuse. Cannabinoid receptors are composed of type 1 receptor (CB1R), type 2 receptor (CB2R) and other receptors, of which CB1R plays a vital role in regulating central memory, cognition, and motor function. Therefore, screening CB1R agonists has potential value in treating nervous system diseases. In this study, the intracellular loop 3 (ICL3) domain of CB1R was replaced with a circular-permutated enhanced green fluorescent protein (cpEGFP). After infecting HEK 293T cells with lentivirus particles, we obtained a stable cell line that was overexpressed human CB1R-cpEGFP after puromycin selection. The interaction between receptor agonists and CB1R led to the change of receptor conformation, resulting in de-protonation of the EGFP, and enhancing the fluorescence intensity. Therefore, active CB1R compounds could be verified by measuring the fluorescence intensity. Using CB1R agonist arachidonyl-2′-chloroethylamide (ACEA) as a positive control to evaluate the reliability of this model, studies have shown that ACEA could induce receptor activation and increase fluorescence intensity, while antagonist rimonabant inhibited receptor activation with unchanged fluorescence intensity. In conclusion, this study successfully constructed a fluorescent probe screening model for CB1R agonists.
A quantitative analysis method for six principal active constituents (acubin, geniposidic acid, chlorogenic acid, pinoresinol di-O-glucopyranoside, geniposide, and pinoresinol 4-O-glucopyranoside) of crude Eucommiae Cortex (EC) and its salt-processed product extracts was developed to investigate and compare their pharmacokinetic behaviors in adenine-induced renal fibrotic rats in vivo. UHPLC-QqQ-MS/MS technology was employed. Scan was conducted in negative ion mode and quantitative determination was carried out by MRM paired ion. The established method was fully validated by specificity, linearity, precision, accuracy, stability, recovery, and matrix effect, and the results of methodological investigation met the requirements of biological sample analysis. Then, a quick, sensitive, and accurate method was successfully established, which could simultaneously measure the contents of six active constituents of crude and salt-processed EC extracts in rat plasma. After a single administration to renal fibrotic rats of crude EC and its salt-processed product extracts, the plasma concentration of each constituent at different time points was measured, the pharmacokinetic parameters were calculated and the concentration time curves were structured. The experiment was approved by the experimental animal ethics committee from Nanjing University of Chinese Medicine (No. 202103A008). The results showed that compared to the crude Eucommiae Cortex group, the tmax of aucubin, pinoresinol di-O-glucopyranoside, geniposide, and pinoresinol 4-O-glucopyranoside in the salt-processed Eucommiae Cortex group rat plasma were significantly lower than those in the crude group (P < 0.05, P < 0.01); the Cmax and AUC0-48 h of chlorogenic acid, the Cmax, AUC0-48 h and AUC0-∞ of pinoresinol di-O-glucopyranoside, and the Cmax of geniposide and pinoresinol 4-O-glucopyranoside were significantly higher than those in the crude group (P < 0.05, P < 0.01). Our investigation found that compared to crude Eucommiae Cortex, a variety of active ingredients could play a role of quick effect with higher peak blood concentration and bioavailability after oral administration of salt-processed Eucommiae Cortex, which were consistent with the traditional Chinese medicine theory of "salt-processing enhancing drug into kidney meridian", providing an experimental basis for the selection of quality control indexes and the in-depth study of processing mechanisms and metabolic rules in vivo of Eucommiae Cortex and its salt-processed product.
Valencene, a kind of sesquiterpenoid with a citrus flavor, is mainly found in Valencia orange and is commonly used in cosmetics and food additives, as well as industrial synthetic nootkatone. In this study, synthetic biology was used to create a Saccharomyces cerevisiae cell factory to produce valencene. Fistly, valencene synthase gene (CnVS) from Callitropsis nootkatensis was inserted into the chromosome of the chassis strain YTT-T5. The resulting strain VAL-01 could produce 1.1 mg·L-1 valencene. Protein fusion technique was used, different valencene synthases were compared and the copy number of key genes was adjusted, yielding valencene to 436.4 mg·L-1. Then, knocking-out the transcription factor ROX1 resulted in valencene improvement by 17.4%. Moreover, the induction system of galactose was regulated, transcription factor PDR3 and INO2 were overexpressed. The engineered strain VAL-10 could produce 2 798.6 mg·L-1 valencene by high cell density fermentation method (nearly 2 500 times higher than VAL-01). This study provides a basis for green production of valencene.
Twenty one flavonoid glycosides were isolated and purified from n-butanol portion of the water extract of A. annua by various chromatographic techniques such as HP-20 macroporous adsorption resin, silica gel, ODS, Sephadex LH-20 gel column chromatography and preparative high performance liquid chromatography. Their structures were identified by analysis of physicochemical properties and spectral data, and determined as axillarin-7-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside (1), orientin (2), apigenin-6-C-β-D-glucopyranosyl-8-C-β-L-arabinopyranoside (3), apigenin-6-C-β-D-galactopyranosyl-8-C-β-L-arabinopyranoside (4), apigenin-6-C-β-L-arabinopyranosyl-8-C-β-D-glucopyranoside (5), apigenin-6-C-α-L-arabinofuranosyl-8-C-β-D-glucopyranoside (6), quercetin-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranoside (7), apigenin-6-C-α-L-arabinopyranosyl-8-C-β-D-glucopyranoside (8), vicenin-2 (9), patuletin-7-O-β-D-glucopyranoside (10), luteolin-6-C-glucopyranoside (11), vitexin (12), kaempferol-3-O-β-galactopyranosyl-(1→2)-β-glucopyranoside (13), quercetin-7-O-β-D-glucopyranoside (14), patuletin-3-O-β-D-glucopyranoside (15), 7-O-methyl-quercetagetin-6-O-β-D-glucopyranoside (16), quercetin-3-O-β-D-glucopyranoside (17), nepitrin (18), rutin (19), kaempferol-3-O-β-sophoroside (20), and patuletin-3-O-rutinoside (21). Compound 1 is a new compound, compounds 2, 4, 6, 7, 10, 11, 13, 15, 16, 18, 20 and 21 are isolated from A. annua for the first time. In the anti-inflammatory assay, compound 1 inhibited the release of IL-6 from LPS-induced RAW264.7 cells to significantly degrees with the high (100 μmol·L-1), medium (50 μmol·L-1), low (25 μmol·L-1) concentration.
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.