To identify an effective structural modification strategy for improving the antitumor activity of fluoroquinolones, sixteen new 1-cyclopropyl-6-fluoro-7-(4-methyl-piperazin-1-yl)-3-arylidene-2, 3-dihydroquinolin-4(1H)-ones compounds (4a-4p), were designed and synthesized by a condensation reaction of dihydroquinolin-4-one (3) and aromatic aldehydes, based on the structure of ciprofloxacin (1). Their structures were characterized by elemental analysis and spectral data, and anti-cell proliferative activities against Hep-3B, Capan-1 and HL60 cell lines were measured by an MTT assay. Preliminary pharmacological results indicated that the synthesized target compounds had greater potency than ciprofloxacin (1). SAR revealed that the halophenyl compounds such as fluorophenyl (4h, 4i), chlorophenyl (4j, 4k) or bromophenyl compounds (4l, 4m) and aromatic heterocyclic compounds such as furanly (4n) or pyridyl compounds (4o, 4p) demonstrated better activity than the control compounds, and the IC₅₀ values of the chlorophenyl compounds 4j and 4k against Capan-1 cell growth were comparable to that of doxorubicin. Thus, a 3-arylidene as an isostere of the C-3 carboxylic acid group appears to be beneficial in improving the antitumor activity of fluoroquinolone. Furthermore, an α, β-unsaturated ketone fragment used as a potential bioisostere of C-3 carboxylic acid group may warrant further study.

This study was designed to investigate the effect of dihydromyricetin (DHM) on inducing apoptosis of ovarian cancer cells A2780 through endoplasmic reticulum stress (ERS) pathway and the mechanisms involved in vitro and in vivo. A2780 cells were treated with different concentrations of DHM, and the protein expression levels of glucose-regulated protein 78 (GRP78) which is related to ERS increased, apoptotic proteins C/EBP-homologous protein (CHOP), and cysteinyl aspartate specific proteinase-12 (caspase-12) elevated. After pretreatment with ERS inhibitor, 4-phenyl butyric acid (4-PBA), following the intervention with DHM, the A2780 cell viability decreased and apoptotic rate increased. All animal welfare and experimental procedures were approved by the Animal Ethics Committee of Chongqing Medical University. Intraperitoneal injection of DHM suspension into nude mice with ovarian cancer could significantly inhibit the growth of transplanted tumor in vivo, increase the protein expression levels of GRP78, CHOP, and caspase-3. Moreover, swollen and broken endoplasmic reticulum could be observed in tumor tissues, suggesting that DHM intervention induces apoptosis mediated by ERS. The results indicated that DHM could induce apoptosis of ovarian cancer cells and inhibit the growth of transplanted tumors in nude mice, which might be related to the activation of ERS pathway.

Glucose-6-phosphate dehydrogenase, a key enzyme in the pentose phosphate pathway, plays an important role in plant resistance. In this study, three full length cDNAs of G6PDH genes, namely AsG6PDH1, AsG6PDH2 and AsG6PDH3 were cloned from Aquilaria sinensis for the first time. The open reading frames (ORF) of AsG6PDH1, AsG6PDH2 and AsG6PDH3 were 1 809, 1 767 and 1 548 bp, respectively, encoding proteins of 602, 588 and 516 amino acid residues, respectively, with predicted molecular masses of 68.02, 67.02, 59.35 kDa, respectively. The three AsG6PDHs proteins shared high sequence identity with the G6PDH proteins of various plants, and possessed three conserved sequences found in G6PDH proteins. The phylogenic analysis showed that AsG6PDH1 and AsG6PDH2 were grouped in the plastidic cluster, while AsG6PDH3 was classified into the cytosolic cluster. Expression analysis indicated that AsG6PDH1 and AsG6PDH2 were primarily observed in root, while AsG6PDH3 was primarily observed in stem. The expression of AsG6PDH1, AsG6PDH2 and AsG6PDH3 was induced by salt, drought, low temperature and CdCl₂ treatments, while the content of AsG6PDH1 and AsG6PDH2 was most significantly increased by drought stress, and the transcript level of AsG6PDH3 was most significantly induced by metal stress. Furthermore, G6PDH activity was stimulated under salt, drought, low temperature and CdCl₂ treatments, and G6PDH activity was remarkably increased under drought stress. These results provide valuable insights into the role of AsG6PDHs in plant defense and the mechanism of agarwood formation.

Gut microbiota dysbiosis is closely related to a variety of host diseases. Recently, targeting the metabolic pathways of gut microbiota for the prevention and treatment of host diseases has become a frontier strategy and research hotspot. Inflammatory bowel disease (IBD) is a group of chronic progressive intestinal inflammatory diseases of unknown etiology. The relationship between IBD and gut microbiota disorders and bacterial respiratory/energy metabolism has been confirmed in recent research. This article will introduce the relationship among them, and propose a new treatment strategy to alleviate host gut inflammation by regulating gut microbiota respiration and energy metabolism based on the latest research progress. In the progression of IBD, the gut microbiota homeostasis is disturbed. The main reasons include two aspects:on the one hand, when the intestinal inflammation of the host occurs, with increasing of oxygen concentration in the intestinal cavity, facultative anaerobic bacteria, especially Enterobacteriaceae bacteria would proliferate abnormally; while the growth of absolute anaerobic bacteria such as Firmicutes is inhibited. On the other hand, intestinal inflammation by-products also support the expansion of facultative anaerobic bacteria, which ultimately exacerbates the imbalance of gut microbiota. Dysregulated intestinal flora will further disturb intestinal immune homeostasis and exacerbate intestinal inflammation. The latest research proposed the possibility that IBD can be alleviated by interfering with the respiration of bacteria, inhibiting the abnormal proliferation of bacteria, or increasing the level of "beneficial" metabolites of gut microbiota. The above studies suggest that alleviating host intestinal inflammation can be explored by focusing on the metabolic pathways of gut microbiota and regulating the intestinal bacterial respiration and energy metabolism, which is of great significance for the clinical treatment of IBD and the research of innovative drugs.

In recent years therapeutic proteins products including therapeutic antibodies have become a major driving force for the modern biopharmaceutical industry. However, they have complex product quality attributes (PQAs) which limit product development and quality control (QC). Recent advances in high resolution mass spectrometry (MS) have led to the use of an MS-based multi-attribute method (MAM) for quality control testing of therapeutic proteins, which allows for direct measurement of multiple PQAs and identification of impurities. MAM helps to promote the improvement of product quality and QC and a reduction in manufacturing cost. To explore the application of MAM in QC, we discuss generic MAM workflow, the current state of MAM application in product development and QC, identify points to consider for use of MAM as a QC test, and summarize MAM's advantages and challenges in this article. The future application of MAM for therapeutic antibodies and the opportunities for its further development, use, and substitution for conventional methods is presented.

Drug metabolites in the systemic circulation can be closely related to the safety or efficacy of drugs, so it is necessary to evaluate the pharmacokinetics of both the parent drug and its major metabolites in plasma. Bisthianostat, a novel histone deacetylase (HDAC) inhibitor, is currently under development. An LC-MS/MS method was developed and validated for the simultaneous determination of bisthianostat and its hydrolyzed N-hydroxyamide metabolite M351 in human plasma to evaluate their pharmacokinetic characteristics in humans. After extraction from the plasma by acetonitrile-induced protein precipitation, the analytes and endogenous substances were separated on a Waters BEH C₁₈ column (2.1 mm×50 mm, 1.7 μm). The mobile phase consisted of acetonitrile and 5 mmol·L^-1 ammonium acetate (containing 0.2% formic acid, v/v) for gradient elution. Positive electrospray ionization was performed using multiple reaction monitoring (MRM) with transitions of m/z 367.1→235.0 for bisthianostat, m/z 352.1→207.0 for M351, m/z 371.1→235.0 for d₄-bisthianostat, and m/z 357.1→208.0 for d₅-M351. The method was linear over a concentration range of 2.00-2000 ng·mL^-1 for bisthianostat and 4.00-4 000 ng·mL^-1 for M351. The results of quality control samples showed that the intra-and inter-day precision were no more than 6.2% for bisthianostat and 6.8% for M351. The accuracy ranged from -1.1% to 4.3% for bisthianostat and -0.5% to 4.9% for M351. The pharmacokinetic results show that after a single oral administration of 100 mg bisthianostat, the time to peak (t_max) of M351 in the plasma of three patients with tumors was significantly longer than that of the parent drug (t_max was 4.00 h and 0.67 h, respectively), and the C_max and plasma exposure of M351 were about 1.7 times and 11 times higher, respectively, than that of the parent drug. This clinical trial was approved by the society of ethics and conducted in Renji Hospital, Shanghai Jiaotong University School of Medicine.

The chemical structures of new components of Epimedium were deduced and verified by combining the secondary metabolism of Epimedium flavonoids with high resolution mass spectrometry. Based on the literature of Epimedium chemistry, the biosynthesis pathway of Yinyanghuo was constructed, and the possible metabolites were deduced. This metabolite information was entered into the PeakView software program and the ions meeting the quality error of less than 5 ppm with correct isotope distribution and containing secondary fragments were taken as the target compounds. Through the use of the software Formula Finder, Mass Calculators, online database (ChemSpider, Metlin, HMDB, etc.) and the fragmentation law of secondary fragments, the chemical structures of 22 metabolites were determined. One new component and eight new compounds were identified in 54 batches of Epimedium samples from 15 varieties by high resolution mass spectrometry. This study avoids the long time and tedious steps of phytochemical separation, saves experimental costs, and provides a new method for the analysis and identification of secondary metabolites with pharmacodynamic activity.

Glucagon-like peptide-1 (GLP-1) could increase the level of cyclic adenosine monophosphate (cAMP) in cells to stimulate insulin secretion in β cells of pancreas. So GLP-1 analogues, such as liraglutide, have become new anti-hyperglycemia drugs for type 2 diabetes. In this study, a set of in vitro activity detection method suitable for GLP-1 analogues was established using GLP-1R-GFP (green fluorescent protein, GFP)-HEK293A cells which stably expressing GLP-1 receptor (GLP-1R). After optimizing the detection parameters such as assay sensitivity, cell density, and the incubation condition, the cAMP content level of GLP-1R-GFP-HEK293A cells stimulated by four GLP-1 analogues, such as liraglutide, were detected by homogeneous time-resolved fluorescence (HTRF). The values of concentration for 50% of maximal effect (EC₅₀) of GLP-1 analogues were calculated by cAMP dose-response curve to evaluate the in vitro activity of those drugs. In addition, enzyme-linked immunosorbent assay and quantitative polymerase chain reaction were applied to determine the content of host cell protein and host residual DNA, respectively. This study provides a stable, reliable, and sensitive in vitro activity analysis and host impurity detection method for high-throughput screening of GLP-1 analogues.

Snake bite is a common acute and severe disease in tropical and subtropical regions, and its public health importance has been largely neglected. Snake venom is a complex mixture of active proteins, polypeptides, and other toxins. Many of these components can target multiple ion channels, cell receptors, and membrane transporters. Compared with traditional small molecule drugs, the proteins and polypeptides from snake venom have stronger specificity and affinity to targets and are especially suitable for novel drug design. The current studies show that snake venom and its components have great potential for development as leading compounds of new drugs. In this paper, the recent advances in main components, toxic effects, and detoxification strategies of snake venom, as well as its pharmacological activities and medical application are reviewed. The aim is to provide reference for clinical diagnosis and treatment of snake bite and development of new drugs based on snake venom.

Angiogenesis is the formation of new capillaries from pre-existing vasculature, which plays a critical role in several diseases. Under the normal physiological conditions, only about 0.5% of endothelial cells (ECs) undergo mitosis, while the most ECs are in a resting state. Angiogenesis is a dynamic process in which ECs shift from resting to activated state, including three basic steps:① excessive vascular endothelial growth factor (VEGF), basic fibroblast growth factor (FGF), platelet-derived endothelial growth factor (PDGF) and other pro-angiogenic factors secreted by ECs can promote the germination of ECs in the original blood vessels; ② the sprouts are continuously elongated through the proliferation of ECs and the degradation and migration of basement membrane. At this time, the ECs present two phenotypes with filamentous feet and strong proliferation ability; ③ the buds are continuously elongated to form a tubular structure and connect with adjacent blood vessels, and the junction is wrapped by wall cells and basement membrane to form new blood vessels. Nowadays, angiogenesis has become a target for clinical treatment of multifarious diseases. On one hand, anti-angiogenesis is used to treat various diseases with excessive angiogenesis, such as cancer, atherosclerosis, and diabetic retinopathy, etc. On the other hand, the diseases caused by insufficient angiogenesis, including myocardial infarction, myocardial ischemia/reperfusion injury, stroke, wound long-term healing and other ischemic diseases can be improved by pro-angiogenesis therapy. Large numbers of researches have shown that many active ingredients of traditional Chinese medicine can effectively treat the previously mentioned diseases by regulating angiogenesis in different ways. Therefore, the anti-and pro-angiogenesis effects of some active ingredients derived from traditional Chinese medicine and their mechanism were summarized in this manuscript, arming to provide theoretical basis for the development of new drugs for the treatment of angiogenesis-related diseases.