To establish and optimize a method for the detection of recombinant human midkine (rhMK) activity and verify its methodology, cell counting kit-8 (cck-8) method was used to measure the proliferation activity of rat knee chondrocytes. The specificity, accuracy, precision, linearity and robustness of the method were also verified in this study. The established method was proven to have good specificity because the buffer of rhMK and recombinant human interleukin-1 receptor antagonist have no obvious active effect; the recoveries of the samples with relative activities of 50%, 75%, 100%, 125%, 150% were in the range of 80.0% to 124.0% by statistical analysis, the relative standard deviations (RSD) of relative potency were all within 20%, the linear correlation coefficient, R² ≥ 0.98, suggesting that the accuracy, precision and linearity of the method were good; the robustness correlation coefficient, R² ≥ 0.92 and the ratio of maximum to minimum of sigmoidal dose-response were no less than 1.5, indicating that robustness of the methods was good. In conclusion, a bioactivity measurement method for rhMK was established and fully validated in this study and it provides a reliable method for the bioactivity analysis of rhMK routine samples during the development. This study was approved by the Animal Care and Use Committee of Shanghai Model Organisms Center, Inc. (approval number: 2019-0008-06).

A novel pair of Z/E isomeric compounds with unprecedented carbon skeleton were isolated from an aqueous extract of Aspongopus chinensis Dallas by macroporous resin, silica gel, and semi-preparative high performance liquid chromatography (HPLC). Their structures were identified by nuclear magnetic resonance (NMR), Infrared spectroscopy (IR), Mass spectroscopy (MS) and other spectroscopic methods as (Z)-3-(but-1″-en-1″-yl)-1-(2ʹ-hydroxyethyl)-4-propylpyridin-1-ium, namely aspongopyridine A, and (E)-3-(but-1″-en-1″-yl)-1-(2ʹ-hydroxyethyl)-4-propylpyridin-1-ium, namely aspongopyridine B, respectively. Besides, the anti-inflammatory, anti-tumor, acetylcholinesterase inhibition and butyrylcholinesterase inhibition activities of the compounds 1 and 2 were evaluated. The results showed that compounds 1 and 2 have no anti-inflammatory, anti-tumor, and butyrylcholinesterase inhibition activities instead of weak acetylcholinesterase inhibition activity.

The purpose of this study was to explore the improving effect of Anshen Dingzhi Prescription (ADP) on Alzheimer's disease (AD)-like behavior in mice and its mechanisms. The main chemical components of ADP were identified by ultra performance liquid chromatography-time-of-flight mass spectrometry (UPLC-Q-TOF-MS). The AD-like mouse model was induced by D-galactose (D-gal) combined with Aβ_1-42 oligomer (AβO). The effect of ADP on AD-like behavior in mice was assessed using various behavioral experiments; pathomorphological changes in mouse hippocampal tissue were observed by Nissl staining and transmission electron microscopy; ELISA was used in the assessment of oxidative stress factors and inflammation-related factor levels; Western blot was performed to detect the expression of Aβ, Tau and glial fibrillary acidic protein (GFAP) proteins. The active components of ADP were screened according to TCMSP and HERB database, and the action targets of active components were predicted by Swiss Target Prediction platform. In addition, the targets of AD were predicted through DisGeNET database. Further, GO and KEGG enrichment analysis of common targets was carried out by Metascape database. Combined with the results of GO and KEGG analysis, in vivo experiments were carried out to explore the potential mechanism of ADP improving AD-like behavior in mice from the PI3K/Akt, calcium signal pathway and synaptic function. Finally, the core components of ADP were molecularly docked to the validated targets using Autodock Vina. Animal experiments were approved by the Animal Ethics Committee of Anhui University of Chinese Medicine (approval number: AHUCM-mouse-2021080). The results showed that the five chemical components, including ginsenoside Rg1, ginsenoside Rb1, tenuifolin, poricoic acid B and α-asarone were found in the ADP. ADP significantly improved the anxiety-like behavior and memory impairment, protected hippocampal neurons, decreased the levels of oxidative stress and inflammation, and inhibited the expression of Aβ and p-Tau induced by D-galactose combined with AβO in mice. The results of network pharmacology suggested that PI3K/Akt, calcium signal pathway and cell components related to postsynaptic membrane might be the key factors for ADP to improve AD. Animal experiments revealed that ADP up-regulated N-methyl-D-aspartate receptor 2A (GluN2A), postsynaptic density protein 95 (PSD95), calpain-1, phosphorylated protein kinase B (p-Akt), phosphorylated cAMP response element binding protein (p-CREB), brain-derived neurotrophic factor (BDNF) expression and inhibited p-GluN2B and calpain-2 expression in the hippocampus of AD-like mice. The molecular docking results demonstrated that the core components of ADP, such as panaxacol, dehydroeburicoic acid, deoxyharringtonine, etc. had a high binding ability with the validated targets GRIN2A, GRIN2B, PSD95, etc. In summary, our results indicate ADP improves AD-like pathological and behavioral changes induced by D-galactose combined with AβO in mice, and the mechanism might be related to the NMDAR/calpain axis and Akt/CREB/BDNF pathway.

Octapeptin has strong antibacterial activity against Gram-negative bacteria such as Escherichia coli, Klebsiella pneumoniae and Acinetobacter baumannii, while it also has activity against some Gram-positive bacteria. This study used natural octapeptin A3 and B3 as lead compounds for structural modification. Twenty-one peptide derivatives (including A3 and B3) containing eight amino acid residues were prepared by solid-phase synthesis, and evaluated for antibacterial activity and renal cytotoxicity. Among them, three compounds 6, 7 and 17 exhibited broad-spectrum antibacterial activity and significantly enhanced the activity for Gram-positive bacteria while maintaining the activity of Gram-negative bacteria. Several compounds improved the activity for Pseudomonas aeruginosa. Compound 7 was active against all test strains and had relatively low renal cytotoxicity. The results provide a basis for the further development of novel polypeptide antibiotics.

Understanding the research methods for drug protein targets is crucial for the development of new drugs, clinical applications of drugs, drug mechanisms, and the pathogenesis of diseases. Cellular thermal shift assay (CETSA), a target research method without modification, has been widely used since its development. Now, there are various CETSA-based technology combinations, such as mass spectrometry-based cellular thermal shift assay (MS-CETSA), isothermal dose response-cellular thermal shift assay (ITDR-CETSA), amplified luminescent proximity homogeneous assay-cellular thermal shift assay (Alpha-CETSA), etc., which combine their respective advantages and further expand the application scope of CETSA. These technologies are suitable for the entire drug development chain, from drug screening to monitoring the target binding and off-target toxicity of drugs in patients. Based on the author's research experience, this paper reviews the principles of CETSA and related binding technologies, their application in target discovery, and the progress of data processing and analysis in recent years, aiming to provide reference and reference for the further application of CETSA.

Salmonella has emerged as a promising tumor-targeting strategy in recent years due to its good tumor targeting ability and certain safety. In order to further optimize its therapeutic effect, scientists have tried to modify Salmonella, including its attenuation and drug loading. This paper summarizes the mechanism and research progress of Salmonella-mediated targeted tumor therapy, and introduces the strategies and related progress of its modification and optimization. At the same time, the advantages, current challenges and future development directions of Salmonella-mediated tumor therapy are summarized.

Fraction absorbed (Fa) is an important parameter to describe the absorption level of oral drugs, and an important basis for the development and optimization of the formulation process. Because it is easily confused with the concept of absolute bioavailability, it has not received enough attention from the industry. There are many complex factors affecting Fa. There are three time-related factors that directly affect the extent of Fa: the release time, the absorption time, and the residence time. The relationship between these three time-related factors determines the extent of Fa. Generally, we are more concerned about the apparent factors that affect the extent of Fa, including independent variables and covariates; The independent variables include administered dose, route, dosage form, etc. The covariates are divided into internal and external factors, and external factors include food factors, drug interactions, etc. Internal causes include age, sex, disease, etc. This paper analyzes and systematically combs how independent variables and covariates directly or indirectly affect the three time-related factors by affecting the body's physiology and internal environment, thus changing the complex process of Fa. Understanding this theoretical framework can better optimize the independent variables to reduce the impact of covariates on Fa. In addition, this paper also introduces the latest progress of prediction and evaluation of Fa, including the progress of complex dissolution device and the status of software prediction.

Cellulose synthase (CesA), one of the key enzymes in the biosynthesis of cellulose in plants, plays an important role in plant growth and plant resistance. In this study, a total of 21 AsCesA genes from Aquilaria sinensis were systematically identified and the physico-chemical characteristics were analyzed based on genome database and bioinformatical methods. The phylogenetic tree was constructed and the gene location on chromosome, cis-acting elements in the 2 000 basepairs upstream regulatory regions and conservative motifs were analyzed. The AsCesA proteins were mainly located on the plasma membrane. The number of amino acids of the proteins ranged from 390 to 1 261. The isoelectric point distributed from 5.67 to 8.86. All of the 21 AsCesA proteins possessed the transmembrane domains, the number of which was from 6 to 8. The genes were classified into 3 groups according to the phylogenetic relationship. Obvious differences were observed in motif composition in genes from different groups. However, motif2, motif6, motif7 and motif10 were observed in all of AsCesA proteins. Analysis of cis-acting elements indicated that AsCesA genes family has cis-acting elements related to plant hormones, abiotic stresses, and biological processes. Seven AsCesA genes with differential expression were selected according to the calli transcriptome data induced by NaCl at different times and their expression levels under different abiotic stresses were analyzed by quantitative real-time PCR. The results indicated that salt, low temperature, drought, and heavy metal stresses could affect the expression level of AsCesA genes, and the abundance of AsCesA1, AsCesA3 and AsCesA20 showed a significant change, implying their potential important roles to the abiotic stresses. The accumulation pattern of cellulose content under different abiotic stresses was similar to the expression trend of AsCesA genes. Our results provide valuable insights into the role of cellulose synthase in A.sinensis in plant defense.

To optimize the formulation and technology of oxymatrine-astragaloside Ⅳ coloaded liposomes (Om-As-Lip) based on quality by design (QbD) principles, and further to verify the feasibility of its amplification process, Om-As-Lip was prepared by ethanol injection combined with pH gradient method. The critical material attributions of Om-As-Lip were evaluated by dual-risk analysis tools and Plackett-Burman design (PBD). The formulation of Om-As-Lip was further optimized with the Box-Behnken design (BBD). The design space was also established based on the contour plots of BBD. In order to further investigate the amplification process of Om-As-Lip, the critical process parameters of high-pressure homogenization (HPH) were optimized by single-factor test, and the quality of the final product was also evaluated. The results of risk analysis and PBD confirmed that the astragaloside concentration, cholesterol concentration, and phospholipid ratio (HSPC∶SPC) were the ctitical material attributes. The model established by BBD had a good predictability, and the optimized mass ratio of As to phospholipids was 1∶40, cholesterol to phospholipids was 1∶10, HSPC to SPC was 51∶9. The design space of Om-As-Lip was as follows: the ratio of cholesterol to phospholipids was 1∶12-1∶5 and HSPC to SPC was 1∶7-17∶3. The optimized high-pressure homogenization pressure was 600 bar, temperature was 4 ℃, and cycle times was 6 times for HPH-Om-As-Lip. The quality of Om-As-Lip prepared based on the QbD concept can meet the expected CQAs, and the formulation and technology established can provide a reliable experimental basis for its future development and applications.

Melatonin (Mel) has been shown to have cardioprotective effects, but its action on ion channels is unclear. In this experiment, we investigated the inhibitory effect of Mel on late sodium currents (I_Na.L) in mouse ventricular myocytes and the anti-arrhythmic effect at the organ level as well as its mechanism. The whole-cell patch clamp technique was applied to record the ionic currents and action potential (AP) in mouse ventricular myocytes while the electrocardiogram (ECG) and monophasic action potential (MAP) were recorded simultaneously in mouse hearts using a multichannel acquisition and analysis system. The results demonstrated that the half maximal inhibitory concentration (IC₅₀) values of Mel on transient sodium current (I_Na.T) and specific I_Na.L opener 2 nmol·L^-1 sea anemone toxins Ⅱ (ATX Ⅱ) increased I_Na.L were 686.615 and 7.37 μmol·L^-1, respectively. Mel did not affect L-type calcium current (I_Ca.L), transient outward current (I_to), and AP. In addition, 16 μmol·L^-1 Mel shortened ATX Ⅱ-prolonged action potential duration (APD), suppressed ATX Ⅱ-induced early afterdepolarizations (EADs), and significantly reduced the incidence of ventricular tachycardia (VT) and ventricular fibrillation (VF) in Langendorff-perfused mouse hearts. In conclusion, Mel exerted its antiarrhythmic effects principally by blocking I_Na.L, thus providing a significant theoretical basis for new clinical applications of Mel. Animal welfare and experimental process are in accordance with the regulations of the Experimental Animal Ethics Committee of Wuhan University of Science and Technology (2023130).