Desorption electrospray ionization mass spectrometry (DESI-MS) is a newly emerging in-situ ionization mass spectrometry analysis technology. The ionization process occurs in an open ambient environment at atmospheric pressure, and has the characteristics of simple sample pretreatment, quick and sensitive analysis, and is widely used in biomedicine, pharmaceutical analysis, food safety, environmental monitoring, and material characterization. Natural medicines, such as Chinese herbal medicines, contain a variety of chemical components. Extraction, separation, identification, and in vitro and in vivo efficacy evaluation of natural medicines, especially research on active ingredients with significant efficacy, have received long-term attention. The development of DESI-MS technology provides many new opportunities for direct and rapid analysis of active ingredients in natural medicines. This article briefly introduces the principles, characteristics, influencing factors, and technical progress of DESI-MS technology, and systematically summarizes progress in the research and application of this technology to natural medicines such as Chinese herbal medicines and other plant samples with pharmacological activity. The future application prospects in this field are further presented.

This study investigates the protective role of IMM-H004, a novel coumarin derivative, on hepatic ischemia-reperfusion injury (HIRI) in mice. All animal experiments in this paper have been approved by the Ethics Committee of Institute of Materia Medica, Chinese Academy of Medical Sciences. The experimental animals were divided into three groups, including sham group, model group, and IMM-H004 treatment group. Serum biochemical indicators were detected and H&E staining was used to assess liver damage. Real-time quantitative PCR (qPCR) was performed to analysis the mRNA content of inflammatory factors. Immunohistochemistry and immunofluorescence were used to observe neutrophil infiltration. Western blot was used to examine the protein levels of NOD-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein (ASC), cysteinyl aspartate specific proteinase-1 (caspase-1), and interleukin-1β (IL-1β). The results showed that IMM-H004 could significantly reduce the serum levels of alanine transaminase (ALT), aspartate transaminase (AST), lactate dehydrogenase (LDH). H&E results showed IMM-H004 could alleviate liver damage caused by HIRI. The mRNA expression of tumor necrosis factor-α (TNF-α), IL-1β, and interleukin-6 (IL-6) were decreased by IMM-H004 administration. Meanwhile, IMM-H004 could markedly inhibit neutrophil infiltration. Furthermore, IMM-H004 could significantly down-regulate the protein expression of NLRP3, ASC, caspase-1, and IL-1β, inhibiting the activation of NLRP3 inflammasome pathway. Our results confirmed that IMM-H004 could protect mice from HIRI and provide a theoretical foundation for IMM-H004 application for treating HIRI.

Hepatocellular carcinoma (HCC) is a serious threat for human health, the incidence of HCC in China accounts for more than 50% worldwide. There is an urgent need to develop novel anticancer agents for the treatment of HCC patients. Here we characterized the inhibitory effect and the molecular mechanism of protopine on HCC cancer cells. The results of a CCK-8 assay indicated that protopine displays anticancer activities on HCC cells. Flow cytometry and JC-1 staining confirmed that treatment with protopine decreased the mitochondrial membrane potential and induced apoptosis in HCC cells. Western blot analysis showed that protopine was able to increase protein expression in the mitochondrial apoptotic pathway; the level of cytochrome C, apoptotic protease activating factor-1 (Apaf-1), Bax, cleaved-poly ADP-ribose polymerase (cleaved-PARP), cleaved-caspase-3, and cleaved-caspase-9 were increased while the expression of Bcl-2 was suppressed significantly. An in vivo study revealed that protopine significantly suppressed the growth of tumors in nude mice bearing HepG2 cells. Administration of protopine intraperitoneally at a concentration of 50 mg·kg^-1 inhibited tumor growth by 72.46%. Animal experiments were carried out according to the Regulation of the Animal Ethics Committee of Southwest Medical University. This study provides preliminary evidence that there is potential to develop protopine as a lead compound for the treatment of HCC.

Excessive exercise makes the body consume more oxygen and produce excessive free radicals. The increased free radicals lead to oxidative stress injury and dysfunctions in liver tissue. Our previous study showed that Anwulignan, an active monomer in Schisandra sphenanthera Rehd. et Wils. (Schisandra), had anti-fatigue effects in mice. However, whether Anwulignan has a protective effect on liver damage in exhausted mice and the mechanism underlying remain elusive. An exhaustive swimming mice model was used to study the protective effects of Anwulignan on liver damage. The involvement of the nuclear factor (erythroid-derived 2)-like 2 (NRF2)/antioxidant responsive element (ARE) antioxidative pathway in Anwulignan-mediated anti-fatigue was analyzed using NRF2 inhibitor ML385 in HepG2 cells treated with H₂O₂. Animal welfare and experimental process follow the regulations of the Animal Ethics Committee of Beihua University. Anwulignan significantly lowered serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, reduced liver tissue damages, increased superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT), and decreased malondialdehyde (MDA) and 8-hydroxy-2 deoxyguanosine (8-OHdG) contents in the livers of exhausted mice, demonstrating a strong antioxidant effect. Furthermore, Anwulignan up-regulated the NRF2/ARE antioxidant pathway in liver tissue, increased B-cell lymphoma 2 (Bcl-2) expression, and decreased Bcl-2-like protein 4 (Bax) and caspase3 expression. In HepG2 cells, Anwulignan improved the cell viability and SOD activity, reduced reactive oxygen species (ROS) and MDA contents, up-regulated the expression of the NRF2/ARE signaling pathway and Bcl-2, and decreased Bax and caspase3 expression in the cells. Furthermore, pretreated ML385 partly abolished all these effects of Anwulignan. Anwulignan protects the liver from damage in the exhausted mice by its antioxidant effects and related to its activation of the NRF2 pathway.

This study investigated the intervention effect and possible mechanism of ophiopogonin D (OPD) in protecting cardiomyocytes against ophiopogonin D' (OPD')-induced injury, and provided relevant experimental data for the clinical use of Ophiopogon japonicas. Cell counting kit-8 (CCK-8) assay was used to evaluate the effect of OPD and OPD' on H9c2 cell viability. The content of reaction oxygen species (ROS) in cells were detected by flow cytometry. The contents of Fe²⁺ in cells were detected by FerroOrange's fluorescence imaging. The content of glutathione (GSH) and glutathione peroxidase (GSH-Px) were detected by kits. The expression of transferrin receptor 1 (TFR1), cyclooxygenase 2 (COX2), NADPH oxidase 1 (NOX1), long-chain acyl-CoA synthetase 4 (ACSL4), cationic amino acid transporter 11 (SLC7A11), glutathione peroxidase 4 (GPX4), and ferritin heavy chain 1 (FTH1) was detected by Western blot. Results showed that OPD' (1 μmol·L^-1) significantly induced the expression of ferroptosis-related proteins, the contents of Fe²⁺, ROS, and GSH-Px were increased, and the content of GSH were decreased. In addition, different concentrations of OPD (0.5, 1, and 2 μmol·L^-1) could partially reverse the myocardial cell injury caused by OPD', and the best effect was obtained when the dose range was 1-2 μmol·L^-1. The experimental results show that OPD can interfere with the ferroptosis caused by OPD', and then have a protective effect on H9c2 cells.

Six compounds were isolated from the crude extract of the liquid culture of Alternaria sp. W-1 by silica gel column chromatography, Sephadex LH-20 gel column chromatography, and HPLC. They were identified as 6-iso-tricycloalternarene 6a (1), tricycloalternarene 6a (2), tricycloalternarene B (3), uracil (4), 5-methyluracil (5), and lumichrome (6) through HR-MS, NMR and literature comparison. 6-iso-Tricycloalternarene 6a (1) is a new compound which has never been reported in the literature. In cytotoxicity assay, compounds 1-3 showed weak inhibition activity to human hepatoma cell line SMMC-7721 and human gastric cell line SGC-7901.

α7 nicotinic acetylcholine receptor (nAChR) is widely distributed in the central and peripheral nervous systems, and is closely related to a variety of neurological diseases and inflammation response. α-Conotoxin[A10L]PnIA, as an antagonist targeting α7 nAChR, plays an important role in studying the physiological and pathological processes involved in α7 nAChR.[A10L]PnIA was labeled with fluorescein 5-carboxytetramethylrho-damine, and the active peptide ([A10L]PnIA-F) was obtained by a two-step oxidative folding procedure in vitro. The Xenopus oocyte expression system and the two-electrode voltage clamp technique were used to identify the potency of[A10L]PnIA-F fluorescent peptide, and its cytotoxicity was detected by mouse macrophages and CCK8 method. The molecular weight of[A10L]PnIA-F fluorescent peptide was identified by mass spectrometry as 2 077.28 Da, which was consistent with the theoretical value. Electrophysiological determination of its halfmaximal inhibitory concentration (IC₅₀) for α7 nAChR is 17.32 nmol·L^-1, which is consistent with[A10L]PnIA (IC₅₀, 13.84 nmol·L^-1). The cytotoxicity test results showed that within the concentration range of 5 nmol·L^-1 to 10 μmol·L^-1, there was no significant inhibition on the growth of mouse macrophages. The results showed that the α-conotoxin fluorescent probe[A10L]PnIA could provide pharmacological tools for the research of α7 nAChRrelated neurophysiological and pathological mechanisms.

In order to clarify the influence of acute hypobaric hypoxia on the bile acids of the rat small intestine, we used ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) to identify bile acids in the contents of the small intestine from untreated and acute hypobaric hypoxia-treated rats. Thirty-nine bile acids were detected; PCA and OPLS-DA analysis revealed marked differences in the composition of bile acids between the untreated and the acute hypobaric hypoxia groups. Bile acids were screened with VIP > 1, |log₂FC|≥ 1, P < 0.05, and a total of 7 bile acids with significant differences in content between the two groups were obtained, including 5 conjugated bile acids, 2 unconjugated bile acids; in addition, the content of conjugated bile acids has risen in the treated group. This study demonstrated the influence of high-altitude hypoxic environment on bile acid composition and metabolism in rats. All the animal experiments in this study were approved by the 940th Hospital Ethics Committee (approval No: 2020KYLL012).

We previously reported that active Astragalus polysaccharides APS-Ⅱ generate strong immune activity. Here we establish the optimal method for APS-II acid degradation. After preliminary structural studies and separation and preparation of the degradation products, the oligosaccharide active center with the strongest immune activity was identified by in vitro immune cell culture experiments. The optimum acid degradation conditions for APS-II were determined by a single factor experiment and an orthogonal experiment. Astragalus oligosaccharides prepared under the optimal conditions were subjected to structural analysis by hydrophilic interaction chromatography-electrospray ionization source-high resolution time-of-flight mass spectrometry. The products were separated and oligosaccharide fragments with different degrees of polymerization were isolated by preparative purification chromatography. Finally, fragments of the immunologically active centers were identified by in vitro immune cell cultures from multiple perspectives. The results show that the optimal acid hydrolysis conditions for APS-Ⅱ are hydrolysis temperature 80℃, trifluoroacetic acid concentration 1.0 mol·L^-1, hydrolysis time 1 h. The degradation conditions have good repeatability. The degradation product is a six-carbon aldehyde glycan structure with the main chain 1→4 connected. The immune activity screening experiment for six oligosaccharide fragments showed that larger molecular weight oligosaccharides have stronger immune-promoting effects. It is speculated that the immunologically active center of Astragalus oligosaccharide is located in the sugar chain of DP9-DP19. The animal welfare and the experimental process in this study follow the requirements of the Animal Ethics Committee of Shanxi University. This result suggests a foundation for the structural characterization and structure-activity relationship research of Astragalus oligosaccharides, and may promote the development of Astragalus oligosaccharide drugs.

The high performance liquid chromatography-fluorescence micelle assay (HPLC-FMA) method for the content determination of polysorbate 80 in monoclonal antibody drugs was validated to study its applicability and transferability between various laboratories, and the feasibility to be included in the Chinese Pharmacopoeia. Both J.T. Baker and Nanjing Well-sourced polysorbate 80 was used in the collaborative validation of polysorbate 80 content analysis in seven different laboratories. The results show that when the protein concentration was no more than 20 mg·mL^-1 and the concentration of polysorbate 80 ranged from 0.05 to 0.5 mg·mL^-1, the method had good specificity. The recovery rates of the spiked samples ranged from 92.20% to 117.70% for J.T.Baker and from 93.90% to 117.20% for Nanjing Well. The intra-laboratory precision (%RSD) was less than 4.30% for J.T. Baker, and less than 2.60% for Nanjing Well, while the overall precision was less than 5.45% for J.T. Baker, and less than 6.70% for Nanjing Well. The linear correlation coefficient was more than 0.98 for J.T. Baker and more than 0.99 for Nanjing Well. The results of the collaborative validation prove that the HPLC-FMA method has good accuracy, precision, linearity, and specificity, and could be used for release control analysis of polysorbate 80 content in monoclonal antibodies across different laboratories.