Latest ArticlesAfter entering the physiological environment, proteins and other biomolecules bind to the nanoparticles' surface, called protein corona. The corona establishes a new bio-interface that affects its physicochemical properties and biological behaviors. Variations in types and contents of human plasma proteins during the different physiological states can substantially change the composition and effects of the corona. With folic acid(FA)-modified polylactic acid-polyglycolic acid copolymer(PLGA) nanoparticles, the formation of protein coronas and their influence on the targeting capability are studied in healthy and ovarian human plasma. All human plasma samples were collected at the Peking University Third Hospital and this study protocol has been approved by Peking University Third Hospital Medical Science Research Ethics Committee(2019-409-1). Dynamic light scattering measurements demonstrated a 10-40 nm increase in their size distributions and a 30 mV decreased in their absolute zeta-potential since protein corona-coated PLGA-PEG and PLGA-FA were formed. The SDS-PAGE analysis showed the composition of the protein coronas from ovarian and healthy plasma in PLGA-FA were markedly distinct, particularly for proteins with molecular weight of 45, 110 and > 180 kDa. Flow cytometry indicated that the absorption of ovarian plasma in PLGA-FA led to a lower cellular uptake by SKOV3 cells. Our results suggest that in vitro formed ovarian plasma protein corona could shield targeting molecules and reduced receptor-mediated internalization. The results of this pilot study will provide evidence of the effectiveness of active targeting nanoparticles under pathologic conditions. Additionally, the protein corona in different diseases is emerging as a key point; thus, a comprehensive understanding could accelerate clinical translation of functionalized nanoparticles.
Ulcerative colitis(UC) is a chronic non-specific inflammatory bowel disease, listed as a modern refractory disease by the World Health Organization, which is difficult to recover, whereas it is easy to be attacked repeatedly. UC pathogenesis is closely related to gut microbiota dysbiosis. The gut microbiota interacts with bile acids(BAs), short-chain fatty acids(SCFAs), tryptophan, and other metabolism, immune system, intestinal barrier, etc., which regulate each other and affect the occurrence and development of UC. The active ingredients of traditional Chinese medicine(TCM), single herb and its extracts, and formulae can effectively alleviate UC symptoms by regulating the diversity, structure, composition, and metabolites of gut microbiota. In this review, the TCM based on the regulation of gut microbiota in the treatment of UC and its related mechanism for nearly three years was summarized.
Antibody-drug conjugates(ADCs) are one of the most important classes of anticancer therapeutics.Human epidermal growth factor receptor-2(HER2), which is highly expressed in many types of aggressive cancers including breast and ovarian cancer, has been approved as an ideal target for ADCs. Lidamycin(LDM), developed by Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences, is an enediyne-containing antibiotic with potent anti-tumor activity. LDM is a promising payload for ADCs. In the present research, using a special site-directed conjugating technology, we made a novel ADC(607-LDM) with a drug-to-antibody ratio(DAR) of 2 and composed of the anti-HER2 antibody 607 and LDM. The new ADC exhibited potent antitumor activity against human ovarian cancer SKOV3 and breast cancer BT-474 cells. It also induced apoptosis and G2/M arrest.In nude mice with SKOV3 xenografts and a tumor volume of 150-200 mm3, a single intravenous injection 607-LDM at 1 mg·kg-1 induced tumor growth inhibition of 72.4%, which was significant compared to either LDM(50.6%) or antibody(30.2%) treatment alone, or both in combination(50.1%, P < 0.05). All animal experiments were performed in accord with National Regulations and approved by the Animal Experiments Ethical Committee of College of Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences. The novel ADC designed in this study, 607-LDM, is a promising candidate for the treatment of HER2-positive cancers.
Salvianolic acids are the main water-soluble active compounds of Salvia miltiorrhiza and have been widely used for the treatment of cardiovascular diseases. Based on the latest studies in China and abroad, we summarize the pharmacological effects and mechanism of salvianolic acids on ischemic heart disease by describing how salvianolic acid A and salvianolic acid B protect the vascular endothelium, relax coronary arteries, promote angiogenesis and anti-platelet aggregation, inhibit the inflammatory response, anti-cell apoptosis, and scavenge free radicals. This review provides a theoretical basis for further research on the effects of salvianolic acids on ischemic heart disease and their potential for drug development.
Sacubitril valsartan sodium(LCZ696) is an ionic cocrystal drug. The purpose of this study was to explore the cocrystal features of LC696 by establishing a variety of characterization methods, and thus provide basic research data for effective quality control. The cocrystal characteristics of LCZ696 and its tablets were identified by applying analytical means including powder X-ray diffraction(PXRD), fourier transform infrared spectroscopy(FTIR), Raman spectra(RM), differential scanning calorimetry(DSC) and solid-state nuclear magnetic resonance spectroscopy(ssNMR). The crystalline water and hygroscopicity of LCZ696 were analyzed by thermogravimetric analysis(TGA), dynamic vapor sorption(DVS), hygroscopicity test and Karl Fischer reaction method.The results show that PXRD, FTIR, DSC and ssNMR can effectively distinguish the features of LCZ696 cocrystal, sacubitril monomer, valsartan monomer, and sacubitril-valsartan(1∶1) mixture. RM can be used as a supplementary approach. Combined with the analysis by TGA, DVS, hygroscopicity test and Karl Fischer reaction method results, LCZ696 contains 2.5 crystalline water molecules and is very hygroscopic; we recommend that LCZ696 be stored in an environment with a relative humidity below 60%. By characterizing the crystal features we can establish quality control measure and evaluate the stability of the drug tablets. This study provides data in support for the establishment of the LCZ696 quality standard.
The antidepressant effect of Xiaoyaosan has been demonstrated. It is of value to explore the biological mechanism of Xiaoyaosan in the treatment of depression from the perspective of functional modules by using the method of functional module division of the metabolic network. The differential metabolites and related enzymes and proteins regulated by Xiaoyaosan were identified in the database. Pathway enrichment analysis and crosstalk pathway analysis of Xiaoyaosan regulated metabolites was carried out. A network of differentially regulated metabolites and their enzymes and proteins was constructed by using the STRING tool. The CNM decomposition algorithm was used to extract the functional modules of the network and enrichment analysis of functional modules was carried out. The results show that Xiaoyaosan regulates 97 differential metabolites, 234 related enzymes and258 depression-related proteins. The pathways crosstalk analysis was divided into two sub-networks, one of which is related to the neural system and cell signal transduction, the other is related to the endocrine system and metabolic pathways. KEGG pathway enrichment analysis of the network and 9 functional modules extracted by the CNM algorithm shows that module 1 and module 3 belong to the pathways that can be enriched into more pathways with fewer proteins. The corresponding functions of these pathways include the endocrine system, amino acid metabolism, the nervous system and signal transduction. In this study, pathway crosstalk analysis and metabolic network module division strategies were used to explain the biological mechanism of Xiaoyaosan in the treatment of depression, providing ideas and methods for in-depth study of the pharmacological mechanism of this traditional Chinese medicine from the perspective of metabolic regulation.
The purpose of this study was to discover novel inhibitors of sirtuin-1(SIRT1) that could be used in the treatment of acute myeloid leukemia(AML).Eight potential SIRT1 inhibitors were identified from 231 511 natural drug-like molecules by virtual screening-based molecular docking and molecular mechanics-generalized Born surface area(MM-GBSA) calculation of binding free energies.Using existing SIRT1 inhibitor molecules as training and test sets, a series of quantitative structure-activity relationship models were established, and the best quantitative structure-activity relationship(QSAR) model was used to predict the IC50 of these 8 potential inhibitor molecules for SIRT1.Subsequently, molecular dynamics simulations were performed to verify the binding mode and stability of these complexes of potential inhibitors and SIRT1 protein.Finally, the activity of these potential SIRT1 inhibitors was verified by cell proliferation assays of OCI-AML2, OCI-AML3 and MV4-11 cells and SIRT1 enzyme activity assays, and it was found that 5 compounds could inhibit AML cell proliferation.Among them, the most active compound, ZINC000001774455, had an IC50 of 2.29 ± 0.09 μmol·L-1 with OCI-AML2 cells, and at a concentration of 1 μmol·L-1, the inhibitory ratio of this compound on SIRT1 protein activity was 65.33%.ZINC000001774455 can be used as a lead compound for the development of new AML treatments.
Four salts of ticagrelor, ticagrelor-3, 5-dinitrobenzoic acid, ticagrelor-pyrazinamide, ticagrelor-Dproline and ticagrelor-L-proline were prepared by solvent suspension and liquid-assisted grinding to improve the solubility of ticagrelor. The compounds were characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, differential scanning calorimetry, nuclear magnetic resonance spectroscopy, elemental analysis, and the intermolecular salt-bonding forces were analyzed. The equilibrium solubility of salts and pure drug in hydrochloride buffer pH 1.2 and phosphate buffer pH 6.8 were measured by high-performance liquid chromatography.Ticagrelor was salted with 3, 5-dinitrobenzoic acid, pyrazinamide, D-proline, L-proline all in a stoichiometric ratio of 1∶1; with the exception of ticagrelor-D-proline, the solubility of the other three salts provided significantly improved solubility in hydrochloride buffer pH 1.2, and the equilibrium solubility of ticagrelor-3, 5-dinitrobenzoic acid was increased by approximately 1.7 folds as compared to pure drug. Salt-forming technology is convenient and can improve the solubility of ticagrelor.
Thiazolidinediones(TZDs) are currently the only recognized insulin sensitizers available for the clinical treatment of type 2 diabetes. Although their advantages are recognized, the profiles of numerous adverse effects hinder the continued use of these drugs. Peroxisome proliferator-activated receptor γ(PPARγ) is known as a receptor for TZDs, and its underlying mechanisms of pharmacological actions and adverse effects have been deeply explored. To maximally preserve the PPARγ-mediated insulin sensitizing effects and reduce the occurrence of related adverse effects, the concept of "selective PPARγ modulators(SPPARMs)" has been proposed and developed, guiding the development of new drugs. In this review, we summarize the recent research progress in the definition of SPPARMs, the candidate classification and the molecular underpinnings, as well as present the discovery of the YR series compounds as an example, and discuss the potential application prospects of SPPARMs.
RAS, as a well-known proto-oncogene, is the most frequently mutated oncogene in human cancers, yet tremendous efforts over the past 30 years have failed to develop effective therapies for RAS-mutant cancer.Recently, specifically targeting the KRAS-G12C mutant, a frequently occurring KRAS mutation in human cancers, has shown promise in conquering KRAS-mutant cancers, and has inspired interest in this direction. We herein review the very recent progress achieved in the development of covalent inhibitors towards KRAS-G12C mutant, in combinational therapies and in proteolysis-targeting chimeras(PROTACs)-based approaches to disrupt KRASG12C protein. We provide insights for drug discovery against KRAS-G12C-mutated tumors and discuss the potential challenges in this field.