Human mass balance study is a pivotal research in the field of clinical pharmacology, aiming at elucidating the metabolic and excretion pathways of drugs in humans. Currently, human mass balance studies predominantly employ radiolabeling techniques. Recently, both the U.S. Food and Drug Administration (FDA) and the Center for Drug Evaluation (CDE) of the China National Medical Products Administration (NMPA) issued related research drafts and guidelines to encourage and guide the pharmaceutical industry to conduct research in compliance with established standards. The selection of radiolabeling sites is crucial for obtaining critical information on drug metabolism. However, in vivo biotransformation may lead to partial disintegration of the molecular structure, thereby resulting in the loss of metabolic product information of the unlabeled moiety. Administering drugs with different radiolabeling sites separately or in combination, or labeling multiple radioactive isotopes within one molecule, can effectively solve this problem. This article reviews relevant technological progress, analyzes radiolabeling strategies, and discusses the application of drugs with multiple radiolabeling sites in human mass balance studies.

Proteolysis-targeting chimera (PROTAC), as an emerging treatment method, has become one of the hottest technologies in the field of new drug research with a near-20-year development. PROTAC utilizes the natural ubiquitin-protease system in cells to induce targeted protein degradation, especially for protein of interest that are difficult to target by traditional small molecules. Moreover, PROTAC is expected to solve the problem of drug resistance that often occurs with small molecule drugs. However, the excessive relative molecular weight, poor solubility and membrane permeability, and low oral absorption of PROTAC make it challenging to druggability study. Currently, take pharmacokinetic characteristics as the entry point to continuously optimize and improve, so as to accelerate the transformation of PROTAC from laboratory to clinical application. Based on the basic structure and mechanism of PROTACs, this review introduces its pharmacokinetic properties, analyzes how to design efficient and stable PROTAC molecules, summarizes its current research progress in various diseases treatments, evaluates the development prospects and limitations of PROTAC, in order to provide more references for further research and application of PROTAC.

Physiologically based pharmacokinetic (PBPK) models have been widely used to predict various stages of drug absorption, distribution, metabolism and excretion. Models based on machine learning (ML) and artificial intelligence (AI) can provide better ideas for the construction of PBPK models, which can accelerate the prediction speed and improve the prediction quality of PBPK. ML and AL can complement the advantages of PBPK model to accelerate the progress of drug research and development. This review introduces the application of machine learning and artificial intelligence in pharmacokinetics, summarizes the research progress of physiological pharmacokinetic models based on machine learning and artificial intelligence, and analyzes the limitations of machine learning and artificial intelligence applications and their application prospects and prospects.

The conventional oral drug delivery frequently results in the drug elimination before its complete release due to rapid gastric emptying and short gastrointestinal transport time, thus reducing the bioavailability of drug. In order to maintain an effective concentration of drug in the body and maximize its optimal efficacy, the frequency of administrations often needs to be increased. By contrast, gastric retention drug delivery system (GRDDS), as an innovative method of drug delivery, prolongs the retention time of the drug in the stomach and reduces irritation to the gastrointestinal tract. Consequently, it enhances the bioavailability of drug, reduces dosing frequency for patients and improves treatment adherence. In recent years, domestic and foreign studies have been conducted on gastric retention drug delivery systems. Here, we provide a comprehensive overview of the relevant literature published in recent years, examining their current marketing status, various types, as well as in vivo and in vitro evaluation methods.

Tumor is one of the serious problems threatening human health. There are some limitations in the delivery of commonly used tumor therapy technologies, and the therapeutic effect is not satisfactory, so new anti-tumor strategies need to be developed. The process of tumor cells using glycolysis to produce energy under aerobic conditions is called aerobic glycolysis, which is closely related to tumor growth, proliferation and metastasis, and can provide a new target spot for tumor treatment. Nano drug delivery system has been widely used in targeted tumor therapy because of its advantages of targeted drug delivery, improved anti-tumor efficacy and reduced toxic side effects. Numerous studies have shown that more and more nano drug delivery systems regulates aerobic glycolytic metabolism by targeting to potential targets such as signaling factors or reaction products of aerobic glycolytic process in tumors, and therefore enhance the anti-tumor effect. This paper reviews the application of nano drug delivery system in regulating tumor aerobic glycolysis, and provides theoretical references for realizing efficient targeted tumor therapy.

The 2-(2-phenylethyl)chromones were separated from agarwood of Aquilaria agallocha Roxb. and their anti-KRAS mutant non-small cell lung cancer (NSCLC) activities were evaluated. 2-(2-Phenyethyl)chromones in agarwood were separated and purified by silica gel, RP-18 reverse phase silica gel, MCI gel CH20P, Diol, and semi preparative HPLC chromatography techniques, while the structures of the compounds were identified by extensive spectroscopic analysis, such as 1D and 2D NMR and ESI-MS. The cell counting kit 8 (CCK-8) assay was used to screen the anti-tumor activity of the isolated monomeric compounds on three KRAS-mutant NSCLC cells. The cell proliferation, cloning formation, adhesion ability, and cell cycle arrest activity of compound 8 were analyzed. Molecular docking and Western blot experiments were used to study the mechanism of compound 8. The in vivo anti-tumor activity of the compound 8 was evaluated by zebrafish cell derived xenograft (CDX) model. Nineteen known 2-(2-phenylethyl)chromones were isolated from the ethyl acetate extract of agarwood. On A549 (KRAS G12S) cells, compounds 8, 10, and 19 showed good inhibitory activity, on H23 (KRAS G12C) cells, compounds 7, 8, and 19 showed good inhibitory activity, and on H358 (KRAS G12C) cells, compounds 8, 10, and 16 showed good inhibitory activity. Compound 8 had the best inhibitory activity in all three cell lines. It effectively inhibited cell proliferation, clone formation, adhesion ability, and arrested the H23 cell cycle at G2/M phase. Compound 8 could also inhibit the expression of c-Met and its downstream signaling pathways, effectively inhibiting tumor growth in zebrafish CDX model. In conclusion, among the nineteen known 2-(2-phenylethyl)chromones, compound 8 had the best activity and significantly inhibited the proliferation of KRAS-mutant NSCLC cells by arresting the cells in the G2/M phase.

Nitazoxanide is an FDA-approved antiprotozoal drug. Our previous study found that oral administration of nitazoxanide inhibited Western diet (WD)-induced hepatic steatosis in ApoE^-/- mice. However, the specific mechanism remains to be elucidated. In the present study, we performed an untargeted metabolomics approach to reveal the effect of nitazoxanide on the liver metabolic profiles in WD-fed ApoE^-/- mice, and carried out the cellular experiments to elucidate the underlying mechanisms. UPLC-MS-based untargeted metabolomics analysis was used to investigate the effect of nitazoxanide on global metabolite changes in liver tissues. The differential metabolites were screened for enrichment analysis and pathway analysis. Hepatocytes were treated with tizoxanide, the metabolite of nitazoxanide, to investigate the underlying mechanism based on the findings in metabolomics study. The improvement of liver lipid metabolism disorders by nitazoxanide treatment in WD-fed ApoE^-/- mice was mainly through regulating glycerophospholipid metabolism, D-glutamine and glutamate metabolism, glutathione metabolism, and arginine biosynthesis metabolism. Tizoxanide, the active metabolite of nitazoxanide, increased glutathione (GSH) contents and glutamate-cysteine ligase catalytic subunit (Gcl-c) and glutathione reductase (Gsr) mRNA expressions in HepG2 cells. Tizoxanide increased cystathionine β-synthase (CBS) and phosphatidylethanolamine N-methyltransferase (PEMT) protein levels, inhibited lipid accumulation in hepatocytes induced by free fatty acid (FFA). Tizoxanide increased S-adenosyl-L-homocysteine hydrolase (SAHH) protein levels in HepG2 cells and mouse primary liver cells stimulated with free fatty acid (FFA). Tizoxanide increased N-acetyl glutamate synthase (Nags) and carbamoylphosphate synthetase 1 (Cps1) mRNA expressions in HepG2 cells. In conclusion, nitazoxanide improves WD-induced hepatic steatosis in ApoE^-/- mice and the underlying mechanisms include increasing CBS expression, GSH content, PEMT protein expression, Nags and Cps1 mRNA expression in hepatocytes.

2-(4-Methylthiazol-5-yl) ethyl nitrate hydrochloride (W1302) is a nitro containing derivative of clomethiazole, which is a novel neuroprotective agent with both carbon monoxide (NO) donor and weak γ-aminobutyric acid type A (GABA_A) receptor allosteric regulatory excitatory effect. The current study used a rat model of transient middle cerebral arteryocclusion (tMCAO) brain injury to evaluate the therapeutic effect of W1302 on ischemic stroke and explore its potential mechanisms of action. This experiment has been reviewed and approved by the Laboratory Animal Management and Use Committee of the Institute of Materia Medica, Chinese Academy of Medical Sciences (ethical review forms No. 620, 632, 5013). The results showed that gavage administration of 1, 3, and 10 mg·kg^-1 of W1302 can significantly reduce the volume of cerebral infarction in rats with ischemia for 2 h and reperfusion for 24 h, and the therapeutic effect was better than that of 200 mg·kg^-1 of DL-3n-butylphthalide. W1302 significantly increased NO levels in blood and brain tissue. It increased cerebral blood flow and brain adenosine triphosphate (ATP) content after reperfusion, as well as, inhibited the expressions of inflammatory factors tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in brain tissue. The time window of W1302 was between 120-180 min after ischemia. These research results demonstrated that W1302 could increase NO release, dilate blood vessels, and increase cerebral blood flow, improve energy supply to brain tissue and increase ATP levels, and inhibit neuro-inflammation, which playing the protective roles in tMCAO stroke model rats. This provides theoretical support for the clinical application of W1302 in the treatment of ischemic stroke.

Thrombosis is a key factor that increases the mortality rate of COVID-19 patients and causes long COVID sequelae. Guanxinning Tablet (GXNT), which is composed of Salvia miltiorrhiza and Ligusticum Chuanxiong, has significant antithrombotic activity, but the similarities and differences between its anti-conventional thrombus and microthrombus induced by COVID-19 remain unclear. In this paper, the main active components, potential targets and mechanisms of GXNT in the treatment of thrombus and microthrombus caused by COVID-19 were preliminarily revealed by using anti-platelet experiments in vitro, network pharmacology analysis, molecular docking technology and molecular biology experiments. The results of platelet aggregation and adhesion experiments in vitro showed that GXNT had significant anti-platelet aggregation and adhesion activities in a dose-dependent manner. Using network pharmacology analysis, it was revealed that salvianolic acid B, tanshinone ⅡA, caffeic acid and ligustrazine in GXNT could resist thrombus and microthrombus caused by COVID-19 through key targets as the high mobility group box 1 protein (HMGB1), tumor necrosis factor (TNF), interleukin 6 (IL6) and AKT serine/threonine kinase 1 (AKT1). HMGB1 signaling pathway is one of its key common mechanisms. Western blot also indicated that GXNT significantly inhibited the expression of HMGB1 protein in platelets. In summary, this paper explores the similarities and differences between the mechanism of GXNT against conventional thrombus and microthrombus caused by COVID-19 and provides drug reference and theoretical basis for clinical prevention and treatment of long COVID sequelae. The animal experiment has been approved by the Experimental Animal Ethics Committee of Tianjin University of Traditional Chinese Medicine (No. TCM-LAEC2023187g1549).

The objective of this study was to observe the effect of Astragalus membranaceus on high sugar-induced Caenorhabditis elegans, and to explore its mechanism of action. UPLC-MS method was used to identify the components of Astragalus membranaceus. A high glucose model was established by using Caenorhabditis elegans as a model organism, and the effects of Astragalus membranaceus on body length, body bending, swallowing frequency, and reactive oxygen species (ROS) of the nematode were determined; the effects of Astragalus membranaceus on the expression of mRNA of genes related to the protein skinhead-1 (SKN-1) signaling pathway were examined by using the real-time fluorescence quantitative polymerase chain reaction (PCR). The results showed that compared with the normal group, the nematode body length, body bending, and swallowing frequency expression were significantly reduced and the ROS content in the body was significantly increased in the high glucose state; after the administration of Astragalus membranaceus, the body length, body bending, and swallowing frequency expression were significantly increased, and the ROS content was significantly reduced (P < 0.01). Compared with the normal group, SKN-1, superoxide dismutas-3 (SOD-3), glutathione S-transferase 4 (GST-4), and glutathione S-transferase 7 (GST-7) expression were significantly decreased in Caenorhabditis elegans in the high glucose condition; SKN-1, SOD-3, GST-4, and GST-7 expression were significantly increased after administration of Astragalus membranaceus (P < 0.01). In the present study, we demonstrated that Astragalus membranaceus has an effect on high glucose-induced Caenorhabditis elegans nematodes, and its mechanism of action may be through the modulation of the SKN-1 signaling pathwaym in order to ameliorate the oxidative stress response induced by high glucose.