The purity of 4,4′-dimethoxy-5,6,5′,6′-bis (methylenedioxy)-2′-morpholine methylenebiphenyl-2-methyl formate methanesulfonate (IMH), a new drug for fatty liver treatment, was determined through differential scanning calorimetry (DSC). Analysis of two-factor non repeatability method was performed in the investigation the effects of two factors (heating rate and sample weight) on purity determination. The DSC experimental parameters were optimized as follows: heating rate was 10 ℃·min^-1, temperature range was 150-300 ℃, sample weight was 2.0-4.1 mg, and N₂ flow rate was 80 mL·min^-1. The linear correlation coefficient (r) of this DSC method was 0.999 8. The RSD value (n = 6) of precision was 0.03%. The standard value and uncertainty of the purity results of the multiple batches of IMH drugs were (99.74 ± 0.29)%, (99.91 ± 0.28)%, (99.90 ± 0.28)%, and (99.81 ± 0.28)% with inclusion factor (K) of 2 and confidence probability (P) of 0.95. The results were basically consistent with the results of the mass balance method. The DSC mehod is a simple, rapid and accurate method, and provides a new reference method for determining the purity of IMH drugs, improves the accuracy and reliability of purity determination.

In this study, we explored the mechanism of Huganning tablet (HGNP) in the treatment of nonalcoholic fatty liver disease (NAFLD) based on network pharmacology and computer-aided drug design. Firstly, the potential ingredients and targets of HGNP were identified from TCMSP database, Swiss Target Prediction database, Chinese pharmacopoeia (2015) and literatures, and then the targets of HGNP intersected with NAFLD disease targets that obtained in GeneCards database to acquired potential targets. The bioconductor bioinformatics package of R software was used for gene ontology (GO) enrichment and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis. The network of "potential ingredient-key target-pathway" was formed in Cytoscape software to study the interactions between potential ingredients of HGNP, key targets, pathways and NAFLD. Based on the results of network pharmacology, the molecular docking analysis of the key targets and potential active ingredients in HGNP tablets with top degree in the network was conducted using Discovery Studio 2020 software, followed by molecular dynamics simulations, binding free energy calculation, drug-likeness properties analysis and ADMET (absorption, distribution, metabolism, excretion and toxicity) properties prediction. In vitro, HepG2 cells were used to establish steatosis model, and the effects of five key compounds on hepatocyte steatosis were analyzed by oil red O staining and triglyceride (TG) content determination. The results showed that 141 ingredients and 151 potential targets were obtained. A total of 2 526 items and 151 pathways were identified by GO and KEGG enrichment analysis. The molecular docking suggested that five components, isorhamnetin, salvianolic acid B, emodin, resveratrol and rhein, exhibited strong binding ability with key targets [retinoic acid receptor RXR-alpha (RXRA), tumor necrosis factor (TNF), glycogen synthase kinase-3 beta (GSK3B), serine/threonine-protein kinase 1 (AKT1)]. It was further verified that isorhamnetin and salvianolic acid B bind to key targets with good structural stability and binding affinity based on molecular dynamics simulations and binding free energy calculations. The drug-likeness properties, pharmacokinetic properties and toxicity of five key compounds were more comprehensively analyzed through drug-likeness properties analysis and ADMET properties prediction. In vitro, all five compounds, isorhamnetin, salvianolic acid B, emodin, resveratrol, and rhein, improved hepatocyte steatosis of HepG2 cells, confirming the reliability of the present study. In conclusion, based on network pharmacology, computer-aided drug design and in vitro validation, this study investigated the mechanism of HGNP for the treatment of NAFLD at multiple levels and provided a basis for its clinical application.

Protein-protein interaction (PPI) plays an important role in the regulation of life. Most of the PPI interfaces are large and discontinuous, and it is difficult for small molecules to specifically bind to them. Peptides are critical in PPI surface interactions due to their higher affinity and specificity. However, peptides have some defects such as easy hydrolysis by protease and poor membrane permeability. Due to good biocompatibility and chemical diversity, cyclic peptides play an important role in drug discovery. Therefore, the development of efficient cyclic peptide construction methods has become a frontier issue in peptide drug research. In recent years, a series of new progresses have been made in the synthesis strategy and the application of cyclic peptides, providing powerful technical tools for the research and development of cyclic peptide drugs. In this review, the synthesis strategies of cyclic peptides and their application will be reviewed from four aspects: synthesis strategies, property improvement, biological activity and prospect.

This study aimed to assess the hypoglycemic activity, and in vitro inhibition of α-glucosidase, inhibition of the advanced glycation end products (AGEs), and total antioxidant capacity were used to clarify its bioactivity. Furthermore, the potential hypoglycemic active chemical constituents in the aqueous extract of Osmanthus fragrans var. thunbergii flower were characterized using high performance liquid chromatography-electrospray ionization-quadruple time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS) method. The result showed that in vitro inhibition of α-glucosidase of the extract (IC₅₀ = 2.11 ± 0.26 mg·mL^-1) were similar to acarbose (IC₅₀ = 2.88 ± 0.32 mg·mL^-1), and it inhibited the AGEs formation and the total antioxidant capacity in a certain extent. Based on the MS fragmentation pathway analysis of reference chemical acteoside contained in this extract, and related references, 73 constituents were tentatively identified from the aqueous extract of Osmanthus fragrans var. thunbergii flower, including 58 phenylethanoids, 8 caffeoylquinic acids, 1 flavonoid vicenin-2, and 6 common organic chemicals in plant. Furthermore, 8 unknown alkaloids were characterized in this work. Among of these chemicals, 61 phenylethanoids were supposed to be detected for the first time. In conclusion, this work disclosed the potential hypoglycemic active constituents of Osmanthus fragrans var. thunbergii flower.

Malignant tumors are major diseases that endanger human health. Due to their complex and variable microenvironment, most anti-tumor drugs cannot precisely reach the focal tissue and be released in a controlled manner. Intelligent responsive nano carriers have become a hot spot in the field of anti-tumor drug delivery systems. As an excellent nano material, mesoporous silica has the advantages of non-toxic, stable, adjustable pore volume and pore diameter, and easy functional modification on the surface. By virtue of its perceptive response to the tumor microenvironment or physiological changes, it can achieve the targeted drug release or controlled drug release of the drug delivery system in the tissue, making it an ideal carrier for intelligent response drug delivery system. In this paper, we review the design strategies and current research status of smart responsive anti-tumor drug delivery systems based on mesoporous silica, in order to provide a reference for the development of anti-tumor drug nanoformulations.

Epilepsy is a chronic nervous system disease, which affects more than 70 million people all over the world. Although more than 30 kinds of antiepileptic drugs (AEDs) have been on the market, about one third of the patients with epilepsy fail to respond to medical treatment, who become drug-resistant epilepsy patients. Identifying the mechanism and developing effective treatment methods for drug-resistant epilepsy have become a hot area in the field of epilepsy research. This review discussed resent advance on the pathogenesis of drug-resistant epilepsy from the transporter hypothesis, neural network hypothesis and target hypothesis, and we also summarized the existing potential treatment methods and research progress of drug-resistant epilepsy, such as surgical resection, deep brain stimulation, ketogenic diet, precise treatment, and traditional Chinese medicine treatment. Our review may provide useful clues for the mechanisms research and clinical treatments of drug-resistant epilepsy.

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.

Size and surface modification are the two key factors affecting the effect of macrophages polarization induced by superparamagnetic iron oxide nanoparticles (SPIONs). The smaller the particle size, the better the polarization effect of SPIONs. Besides, the reasonable SPIONs surface modification method can also be used to enhance the polarization effect. In this study, SPIONs was prepared by solvothermal method and optimized by Box-Benhnken center combination design and response surface method. Furthermore, astragalus polysaccharide-superparamagnetic iron oxide nanocomplex (APS-SPIONs) was successfully constructed by EDC/NHS esterification method. The structure of APS-SPIONs was confirmed by dynamic light scatter and infrared spectrometer, and the contents of iron and polysaccharide were characterized by spectrophotometry. The effect of APS-SPIONs on inducing mouse macrophages RAW264.7 polarization was investigated by flow cytometry. The RAW264.7 macrophages-HepG2 human hepatoma cancer cells Transwell co-culture system was established to investigate APS-SPIONs improve anti-tumor function of macrophages in vitro, and the proliferation activity of APS-SPIONs on RAW264.7 detected by cell counting kit-8 (CCK-8) method. The results showed that the average particle size and zeta potential of APS-SPIONs were (82.93 ± 1.47) nm and (-24.00 ± 0.47) mV. Polysaccharide and Fe content were 8.69% and 7.04%, respectively. APS-SPIONs effectively induced the polarization of RAW264.7 into M1 type in vitro, improving the anti-tumor ability of macrophages in a co-culture system, without effecting the proliferation of macrophages. Our study provides a drug development strategy and preliminary research results to educate macrophages and reshape the tumor immune microenvironment to achieve tumor-killing effects.

By using computer-aided drug design, the activities group model which CDK4/6 inhibitors on the market were introduced to silybin C-7, and a series of silybin derivatives were designed and synthesized, and the structure was confirmed by MS, ¹³C NMR and ¹H NMR. The in vitro antitumor activity evaluation of the target compound was carried out by MTT method, and the in vitro anti-tumor activity was carried out in human hepatocellular carcinoma cells (HepG-2). Experimental results show that all compounds are higher than the activity of the parent silybin, of which compound I₁ has a certain inhibitory effect on human HepG-2 cells, which is worth further study.

The goal of this work was to explore the prospect of standardized application of an in-vitro bioactivity assay for recombinant human follicle-stimulating hormone based on a reporter gene. The relative accuracy, intermediate precision, linearity and applicable range of the method were validated according to the General Rules of Chinese Pharmacopoeia 2020 edition Volume IV (9401). Three laboratories used this method to determine the in-vitro biological activities of six batches of drug product and three batches of drug substance manufactured by two different companies. The consistency of the potency determined by three laboratories, the intra-laboratory precision and inter-laboratory precision were analyzed. The method was optimized during the collaborative validation. The results of method validation meet the requirements of the General Rules of Chinese Pharmacopoeia 2020 edition Volume IV (9401). Aiming to resolve the problems found in the collaborative validation, the medium for cell seeding, the pre-diluted buffer solution of standard and sample, and the means of removing and discarding supernatant after stimulation were optimized. After optimization, there was no significant difference in the bioactivity among the different laboratories (P > 0.05), indicating statistical equivalency. Intra-laboratory and inter-laboratory precision were good and the geometric coefficient of variation (GCV%) were both less than 15%. In conclusion, the reporter gene assay has good intra-laboratory repeatability and inter-laboratory reproducibility and is suitable for analyzing recombinant human follicle-stimulating hormone drug product and drug substance by different manufacturers. It is expected to be used as a standardized method for the determination of the in-vitro bioactivity of such products.