Biosensor analysis technology and its research progress in drug development of Alzheimer's disease / 药学学报

Biosensor analysis technology is a kind of technology with high specificity that can convert biological reactions into optical and electrical signals. In the development of drugs for Alzheimer's disease (AD), according to different disease hypotheses and targets, this technology plays an important role in confirming targets and screening active compounds. This paper briefly describes the pathogenesis of AD and the current situation of therapeutic drugs, introduces three biosensor analysis techniques commonly used in the discovery of AD drugs, such as surface plasmon resonance (SPR), biolayer interferometry (BLI) and fluorescence analysis technology, explains its basic principle and application progress, and summarizes their advantages and limitations respectively.

The screening model for dopamine receptor agonists by a dopamine sensor / 药学学报

Parkinson's disease (PD) is a degenerative disease of the central nervous system due to the loss or death of dopaminergic neurons in the substantia nigra. Clinically, levodopa is the most effective and commonly used drug for PD treatment. However, long-term levodopa therapy is prone to motor complications and other side effects caused by excessive peripheral dopamine production, which has become an urgent problem to be solved in PD treatment. Dopamine receptor (DR) agonists are similar to dopamine. They can directly stimulate postsynaptic dopamine receptors, produce the same effect as dopamine, delay the application of levodopa as much as possible, and reduce complications caused by long-term use of levodopa. Therefore, screening effective dopamine receptor agonists has become a key issue in the study and treatment of PD. In order to establish a rapid, stable and reliable method for dopamine receptor agonist screening, this study used the human dopamine receptor 2 (DRD2) gene fused with a circular permuted EGFP (cpEGFP) to construct a recombinant gene, packaged with lentiviral vector, and the vector replaced the parted inner transmembrane domain of the third intracellular loop (ICL3) of genetically-encoded GPCR-activation based (GRAB) sensors. The fluorescence of GPCR-fused cpEGFP is regulated by conformational changes mediated by the interaction of dopamine receptor agonists with GPCRs without altering GPCR activity. The HEK293T cells were infected with viral vector, screened by puromycin to select highly expressed cells. Dopamine receptor agonists (including dopamine, bromocriptine mesylate, cabergoline, pramipexole) were used as positive drugs to explore the best screening and detection conditions, establishing a stable model to evaluate the dopamine receptor agonist. The results showed that the optimal filter for the dopamine receptor agonist in this study was the cell seeding count of 7×104, and the effective concentration of the positive drug was 1-100 µmol·L-1. In addition, pretreated with 10 µmol·L-1 dopamine receptor antagonists (including chlorprothixol hydrochloride, domperidone, and sulpiride), the positive fluorescence signal of overexpressed DRD2-cpEGFP HEK293T cells could not be detected when exposed to 10 µmol·L-1 dopamine receptor agonists, which proved that dopamine receptor antagonists could block the activity of dopamine receptor agonists, so they cannot activate dopamine receptor allosteric, indicating that the model has good specificity and can also be used for the screening and detection of new dopamine receptor antagonists. In summary, the study constructs a stable dopamine sensor detection system, which can effectively screen potential dopamine receptor agonists. The operation procedures are simple and rapid. And it can be used for a large-scale screening providing a fundamental methodology for drug development and PD treatment targeted on DRD2.

Advances in research of heart organoid and its application in drug discovery / 药学学报

Cardiovascular diseases are fatal threats to human health and also important fields in drug discovery. Organoid is a miniature with the structure and function similar to the organ, which is formed by the self-updating and specific differentiation of stem cells during the in vitro culture. Considering its characteristics of human origin, physical features, self-assembling and genetic stability, heart organoid has attracted much attention in the study of cardiogenesis, cardiovascular diseases modeling and related drug research. Hence, this article will review the development of heart organoids and its construction strategies, highlighting its application and prospects in drug discovery.

Establishment of a screening cell model for cannabinoid type 1 receptor agonists / 药学学报

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.

Advancements in stabilization technologies for membrane protein and its application in drug screening / 药学学报

Membrane proteins are the main undertakers of biofilm function, and also the most important target group for innovative drug discovery and research. About 60% of drugs targets are membrane proteins. Due to the obvious aggregation and denaturation tendency of membrane proteins in aqueous solution, it is difficult to simulate the membrane like environment to maintain the correct conformation of membrane proteins in vitro, which results in the slower-growing research on the structure and function of membrane proteins and related ligand drugs than that of water-soluble proteins. Membrane protein stabilization technology is the premise of establishing high specificity, high sensitivity and high throughput drug screening methods for membrane protein ligands, which is of great significance. In this paper, some techniques for stable separation and purification of membrane proteins are reviewed, including detergents, artificial membranes, polymers, lentiviral particles and so on, as well as their specific applications in drug screening.

Research progress on STAT protein inhibitors in the treatment of lymphoma / 药学学报

The abnormal activation and mutation of signal transducer and activator transcription (STAT) proteins has been implicated in multiple lymphomas. The research discovery and clinical application of STATs inhibitors have become an important strategy for treating lymphoma. This review introduces the abnormal activation and mutation of STATs in multiple malignant lymphomas, and focuses on reviewing the latest screening strategies targeting STATs and its clinical application in the treatment of lymphoma, providing references for the further development of STATs inhibitors.

Construction of a drug screening model for miscarriage from induced pluripotent stem cells in vitro / 药学学报

Drug use during pregnancy is unavoidable. Therefore, it is vitally important for medical workers to help pregnant women take drugs correctly to reduce the incidence of spontaneous abortion, premature birth, and low birth weight. In our study, drug screening model with induced pluripotent stem cells (iPSCs) was used to find some improper drugs which will result in woman's abortion. With 3D culture in vitro, iPSCs can form embryoid bodies (EBs) and cerebral organoids, which simulated in vitro development of early embryos, from inner cell mass to germ-layer differentiation. In the experiment, EBs were exposed to mifepristone (RU486), and three experimental groups were divided randomly. They were control group (without RU486), low-dose group (L-RU486, 10 μg·mL-1), and high-dose group (H-RU486, 20 μg·mL-1). After mifepristone exposure, EBs were observed at days 5, 8, and 11, including size of EB, cell apoptosis, and differentiation of germ layers, by using inverted optical microscope, TUNEL assay, and immunofluorescent staining. The results showed that through 3D culture, iPSCs could develop into embryoid bodies, neural rosettes, and finally cerebral organoids. After mifepristone exposure, EBs' sizes were decreased (P < 0.01); the levels of cell apoptosis in EBs were increased after mifepristone exposure (P < 0.01); the development of EBs' germ layer was affected. Mifepristone exposure could inhibit the proliferation of embryonic stem cells, reduce the differentiation of ectoderm (P < 0.01) and promote the development of mesoderm (P < 0.05). In conclusion, iPSCs can be used as a screening model for abortion drug, and EBs’ diameter, cell apoptosis, and differentiation changes of the germ layers can serve as criteria of abortion drug screening.

Construction of a concentration gradient microfluidic chip platform for the rapid screening of drugs active against Candida albicans / 药学学报

Drug screening against Candida albicans has become more urgent due to the increasing incidence of infection and the development of drug-resistant strains. The microfluidic chip technique has shown great potential for high-throughput drug screening. In this study we developed a concentration gradient microfluidic chip platform for drug screening against Candida albicans. The generated concentration gradient on this platform was investigated qualitatively by monitoring the distribution of the fluorescent tracer fluorescein sodium and quantitatively by following the distribution of the model drug fluconazole as analyzed by HPLC; the effect of different flow conditions on the concentration gradient were determined. The ratio of the two aqueous phase flow rates was determined in the subsequent drug screening studies. Alamar Blue, an indicator of cell viability, was used in the susceptibility test for amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, terbinafine, 5-fluorocytosine and caspofungin as carried out on the established chip platform. The MIC range of the drugs, which was consistent with the MIC values of the CLSI-recommended standard, were obtained quickly and efficiently through the use of this platform, indicating that this new platform can quickly screen a series of antibacterial drugs in one run. In addition, the strain of Candida albicans we used showed resistance to terbinafine in our platform assay, consistent with the results of a 96-well plate assay, indicating that the platform can also be used for rapid screening of resistant strains.