Flavonoids with Anti-Angiogenesis Function in Cancer.

The formation of new blood vessels, known as angiogenesis, significantly impacts the development of multiple types of cancer. Consequently, researchers have focused on targeting this process to prevent and treat numerous disorders. However, most existing anti-angiogenic treatments rely on synthetic compounds and humanized monoclonal antibodies, often expensive or toxic, restricting patient access to these therapies. Hence, the pursuit of discovering new, affordable, less toxic, and efficient anti-angiogenic compounds is imperative. Numerous studies propose that natural plant-derived products exhibit these sought-after characteristics. The objective of this review is to delve into the anti-angiogenic properties exhibited by naturally derived flavonoids from plants, along with their underlying molecular mechanisms of action. Additionally, we summarize the structure, classification, and the relationship between flavonoids with their signaling pathways in plants as anti-angiogenic agents, including main HIF-1α/VEGF/VEGFR2/PI3K/AKT, Wnt/ß-catenin, JNK1/STAT3, and MAPK/AP-1 pathways. Nonetheless, further research and innovative approaches are required to enhance their bioavailability for clinical application.

Functional characterization of alkaline phosphatases involved alarm pheromone in the vetch aphid Megoura viciae.

The alkaline phosphatases (ALPs) are highly promiscuous enzymes and have been extensively investigated in mammals for their medical significance, but their functional promiscuity is relatively poorly understood in insects. Here, we first identified four ALP genes (designated as MvALP1-4) in the vetch aphid Megoura viciae that contained one alkaline phosphatase site, three metal-binding sites, and varied other functional sites. Phylogenetic analysis, molecular docking and the spatiotemporal expression profiling of MvALP1-4 were very different, indicating a promiscuous functionality. We also found that MvALP4 involved the biosynthesis of aphid alarm pheromones (EßF) in vitro and in vivo. Finally, transcriptome analysis in the stimulated and unstimulated aphids supported the involvement of MvALPs in the biosynthesis of aphid alarm pheromones. Our study identified a multifunctional ALP involved terpene synthase enzyme activity in the aphid, which contributes to the understanding of the functional plasticity of ALPs in insects.

Corn Silk Polysaccharides with Different Carboxyl Contents Reduce the Oxidative Damage of Renal Epithelial Cells by Inhibiting Endocytosis of Nano-calcium Oxalate Crystals.

OBJECTIVE: Renal epithelial cell injury and cell-crystal interaction are closely related to kidney stone formation. METHODS: This study aims to explore the inhibition of endocytosis of nano-sized calcium oxalate monohydrate (nano-COM) crystals and the cell protection of corn silk polysaccharides (CCSPs) with different carboxyl contents (3.92, 7.75, 12.90, and 16.38%). The nano-COM crystals protected or unprotected by CCSPs were co-cultured with human renal proximal tubular epithelial cells (HK-2), and then the changes in the endocytosis of nano-COM and cell biochemical indicators were detected. RESULTS: CCSPs could inhibit the endocytosis of nano-COM by HK-2 cells and reduce the accumulation of nano-COM in the cells. Under the protection of CCSPs, cell morphology is restored, intracellular superoxide dismutase levels are increased, lipid peroxidation product malondialdehyde release is decreased, and mitochondrial membrane potential and lysosomal integrity are increased. The release of Ca2+ ions in the cell, the level of cell autophagy, and the rate of cell apoptosis and necrosis are also reduced. CCSPs with higher carboxyl content have better cell protection abilities. CONCLUSION: CCSPs could inhibit the endocytosis of nano-COM crystals and reduce cell oxidative damage. CCSP3, with the highest carboxyl content, shows the best biological activity.

Ultrasound-assisted polysaccharide extraction from Cercis chinensis and properites, antioxidant activity of polysaccharide.

The purpose of the study was to improve the extraction of polysaccharide from the leaves of Cercis chinensis Bunge using ultrasound, and compare the difference between boiling and ultrasound extraction in terms of polysaccharide content, monosaccharide compounds, and evaluate how the factors affected the bioactivity. The best conditions, according to the single factor experiments and the Box-Bohnken design (BBD), were an intensity of ultrasound of 180 W, duration of extraction of 40 min, proportion of water to material of 15:1 (g/g), and a higher polysaccharide yield of 20.02 ± 0.55 (mg/g) than in boiling extraction (16.09 ± 0.82 mg/g). The antioxidative experiment suggested the polysaccharide by ultrasound exhibited higher DPPH, hydroxyl radical scavenging capacities, and reducing power at 1.2-1.4 mg/mL, which was superior to the boiling polysaccharide. Further analysis showed that the ultrasonic purified polysaccharides like Gla, N-Glu, and GluA contained more total sugar and uronic acids than the boiling method did. This may indicate that the ultrasonic isolation of the polysaccharides increase the antioxidant activity of the polysaccharides.

Cell Protection and Crystal Endocytosis Inhibition by Sulfated Laminaria Polysaccharides Against Nano-COM-Induced Oxidative Damage in Renal Epithelial Cells.

Background: The damage to renal tubular epithelial cells is closely related to the formation of kidney stones. At present, research on drugs that can protect cells from damage remains limited. Methods: This study aims to explore the protective effects of four different sulfate groups (-OSO3 -) of Laminaria polysaccharides (SLPs) on human kidney proximal tubular epithelial (HK-2) cells and determine the difference in the endocytosis of nano-sized calcium oxalate monohydrate (COM) crystals before and after protection. COM with a size of 230 ± 80 nm was used to damage HK-2 cells to establish a damage model. The protection capability of SLPs (LP0, SLP1, SLP2, and SLP3) with -OSO3 - contents of 0.73, 15, 23, and 31%, respectively, against COM crystal damage and the effect of SLPs on the endocytosis of COM crystals were studied. Results: Compared with that of the SLP-unprotected COM-injured group, the cell viability of the SLP-protected group was improved, healing capability was enhanced, cell morphology was restored, production of reactive oxygen species was reduced, mitochondrial membrane potential and lysosome integrity were increased, intracellular Ca2+ level and autophagy were decreased, cell mortality was reduced, and internalized COM crystals were lessened. The capability of SLPs to protect cells from damage and inhibit the endocytosis of crystals in cells enhanced with an increase in the -OSO3 - content of SLPs. Conclusions: SLPs with a high -OSO3 - content may become a potential green drug for preventing the formation of kidney stones.

Composition and Antioxidative and Antibacterial Activities of the Essential Oil from Farfugium japonicum.

The composition of volatile oils of the leaf and stem of Farfugium japonicum (L.) Kitamura were prepared by supercritical fluid extraction (SFE)-CO2. A total 47 and 40 compounds were identified by GC/MS analysis, respectively, and only 13 compounds coexisted. The main constituent types in the leaf oil included alcohols (34.1%), hydrocarbons (24.1%), terpenoids (16.2%), benzenes (7.5%), and fatty acids (4.9%). In the stem oil, the constituent types chiefly included benzenes (18.8%), ketones (13.9%), terpenoids (17.0%), fatty acids (8.8%), phenolics (8.7%), steroids (8.6%), hydrocarbons (8.0%), and esters (5.7%). The predominant volatile compounds in the stem were 2-(1-cyclopent-1-enyl-1-methylethyl) cyclopentanone (11.7%), 1,2,3,4,5,6,7,8-octahydro- 9,10-dimethyl-anthracene (8.4%), 5-heptylresorcinol (6.5%), and α-sitosterol (5.2%). Those in the leaf mainly included (E)-3-hexen-1-ol (13.7%) and (Z)-3-hexen-1-ol (14.0%). This demonstrated a significant difference in the composition of both oils. Further study showed that stem oils demonstrated the highest DPPH (1,1-diphenyl-2-pinylhydrazyl) and ·OH free radical scavenging capacities at IC50 values of 9.22 and 0.90 mg/mL, respectively. In addition, they demonstrated the strongest antibacterial capacity against the Gram-positive bacteria methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) at a minimum inhibitory concentration (MIC) of 0.16 mg/mL. This could be due to the SFE-CO2 extraction and the high accumulation of benzenes, terpenoids, and phenolics in the stem. In particular, the monoterpenes presented in terpenoids could play a special role in these findings.

Farnesyl/geranylgeranyl diphosphate synthases regulate the biosynthesis of alarm pheromone in a unique manner in the vetch aphid Megoura viciae.

Farnesyl/geranylgeranyl diphosphate synthases (FPPS/GGPPS) as the short-chain prenyltransferases catalyse the formation of the acyclic precursors (E)-FPP and (E)-GGPP for isoprenoid biosynthesis. Here, we first cloned the cDNAs encoding FPPS and GGPPS in the vetch aphid Megoura viciae (designated as MvFPPS and MvGGPPS). They had an open reading frame of 1185 and 930 bp in length, encoding 395 and 309 amino acids, with a theoretical isoelectric point of 6.52 and 6.21, respectively. Sequence alignment and phylogenetic analysis showed that MvFPPS and MvGGPPS shared the conserved aspartate-rich motifs characterized by all prenyltransferases identified to date and were clustered with their homologues in two large clades. RNA interference (RNAi) combined with gas chromatography/mass spectrometry (GC-MS) analysis showed that both MvFPPS and MvGGPPS were involved in the biosynthesis of alarm pheromone. Spatiotemporal expression profiling showed that the expression of MvFPPS and MvGGPPS was significantly higher in embryos than in other tissues. RNAi and GC-MS performed specifically in embryos corroborated the function of MvFPPS and MvGGPPS. In vitro, enzymatic activity assay and product analysis demonstrated that MvFPPS could catalysed the formation of (E)-FPP using DMAPP or (E)-GPP as the allylic cosubstrates in the presence of IPP, while MvGGPPS could only use (E)-GPP or (E)-FPP as cosubstrates. Functional interaction analysis using RNAi revealed that MvGGPPS exerts unidirectional functional compensation for MvFPPS. Moreover, it can regulate the biosynthesis of alarm pheromone by imposing a negative feedback regulation on MvFPPS. Our study helps to understand the molecular regulatory mechanism of terpenoid biosynthesis in the aphid.

Detection of Cytb Point Mutation (G143A) that Confers High-Level Resistance to Pyraclostrobin in Glomerella cingulata Using LAMP Method.

Glomerella leaf spot (GLS) caused by Glomerella cingulata is a newly emerging disease that results in severe defoliation and fruit spots in apples. In China, the compound of pyraclostrobin and tebuconazole was registered to control GLS in 2018 and has achieved excellent control efficiency. In this study, we showed that the high-level resistant isolates of G. cingulata to pyraclostrobin, caused by the point mutation at codon 143 (GGT→GCT, G143A) in the cytochrome b gene, has appeared in apple orchards in Shandong Province in 2020, and the resistance frequency was 4.8%. Based on the genotype of the resistant isolates, we developed a loop-mediated isothermal amplification (LAMP) assay for detection of the pyraclostrobin resistance. The LAMP assay was demonstrated to have good specificity, sensitivity, and repeatability, and it exhibited high accuracy in detecting pyraclostrobin resistance in the field. This study reported the resistance status of GLS to pyraclostrobin in Shandong Province and developed a molecular tool for the detection of pyraclostrobin resistance, which is of practical significance for the scientific control of GLS.

Novel quinoline-based derivatives as the PqsR inhibitor against Pseudomonas aeruginosa PAO1.

AIMS: The emerging of drug resistant Pseudomonas aeruginosa is a critical challenge and renders an urgent action to discover innovative antimicrobial interventions. One of these interventions is to disrupt the pseudomonas quinolone signal (pqs) quorum sensing (QS) system, which governs multiple virulence traits and biofilm formation. This study aimed to investigate the QS inhibitory activity of a series of new PqsR inhibitors bearing a quinoline scaffold against Ps. aeruginosa. METHODS AND RESULTS: The results showed that compound 1 suppressed the expression of QS-related genes and showed the best inhibitory activity to the pqs system of wild-type Ps. aeruginosa PAO1 with an IC50 of 20.22 µmol L-1 . The virulence factors including pyocyanin, total protease, elastase and rhamnolipid were significantly suppressed in a concentration-dependent manner with the compound. In addition, compound 1 in combination with tetracycline inhibited synergistically the bacterial growth and suppressed the biofilm formation of PAO1. The molecular docking studies also suggested that compound 1 could potentially interact with the ligand-binding domain of the Lys-R type transcriptional regulator PqsR as a competitive antagonist. CONCLUSIONS: The quinoline-based derivatives were found to interrupt the quorum sensing system via the pqs pathway and thus the production of virulence factors was inhibited and the antimicrobial susceptibility of Ps. aeruginosa was enhanced. SIGNIFICANCE AND IMPACT OF STUDY: The study showed that the quinoline-based derivatives could be used as an anti-virulence agent for treating Ps. aeruginosa infections.

Comparative Analysis of Differentially Expressed Circular RNAs in Polarized Macrophages.

Macrophage polarization is a process that macrophages exert different functions according to surrounding micro-environment. Macrophages commonly exist in two distinct subsets: classically activated M1 macrophages and alternatively activated M2 macrophages. Circular RNAs (circRNAs) are a novel class of non-coding RNAs generated by back-splicing. Thousands of circRNAs were identified in different cells and tissues. Recent studies have revealed that circRNAs play a crucial role in regulating transcriptional and post-transcriptional gene expression. However, the effects and roles of circRNAs in macrophage polarization have not been well elucidated. Here, circRNAs expression profiles were determined in human THP-1 macrophages incubated in conditions causing activation toward M1 (interferon-γ + LPS) or M2 (interleukin-4) phenotypes. Overall, 9,720 circular RNA were detected from RNA sequencing data. Compared with M2 macrophages, a total of 140 circRNAs were aberrantly expressed in M1 macrophages, including 71 up-regulated circRNAs and 69 down-regulated circRNAs. Quantitative real-time PCR (qRT-PCR) results were generally consistent with the selected differentially expressed circRNAs. Gene Ontology (GO) and KEGG pathway analyses were used to predict biological functions and potential mechanisms of the host linear transcripts of these up-regulated and down-regulated circRNAs. Furthermore, we found that the expression level of circRNA-RNF19B (circRNF19B) in M1 macrophages was significantly higher than that in THP-1 macrophages and M2 macrophages. circRNF19B expression was increased when M2 converted to M1 whereas decreased when M1 converted to M2. Knockdown of circRNF19B following the activation of THP-1 cells using interferon-γ + LPS diminished the expression of M1 macrophages markers and elevated the expression of M2 macrophages markers. In conclusion, these data suggest the involvement of altered circRNAs expression patterns in macrophages exposure to different activating conditions. Circular RNAs may play important roles in regulating macrophage polarization.

Design and synthesis of quinolinium-based derivatives targeting FtsZ for antibacterial evaluation and mechanistic study.

The discovery of small molecular inhibitors targeting essential and conserved bacterial drug targets such as FtsZ protein is a promising approach to fight against multi-drug resistant bacteria. In the present study, two new series of FtsZ inhibitors based on a 1-methylquinolinium scaffold were synthesized. The inhibitors possess a variety of substituent groups including the cyclic or linear amine skeleton at the 2- and 4-position of the quinolinium ring for structure-activity relationship study. In general, the inhibitors bearing a cyclic amine substituent at the 4-position of the quinolinium ring showed better antibacterial activity (MIC down to 0.25 µg/mL) than that at the 2-position, especially against Gram-positive bacteria. Among the twenty FtsZ inhibitors examined in various assays, A3 was identified to exhibit excellent antibacterial activity against S. aureus (MIC = 0.5-1 µg/mL), S. epidermidis (MIC = 0.25 µg/mL) and E. faecium (MIC = 1-8 µg/mL). More importantly, A3 showed low hemolytic toxicity (IC5 = 64 µg/mL) and was found not readily to induce drug resistance. A3 at 2-8 µg/mL promoted the polymerization of FtsZ and interrupted the bacterial division. Furthermore, the ligand-FtsZ interaction study conducted with circular dichroism and molecular docking revealed that A3 induced secondary structure changes of FtsZ protein upon binding to the interdomain cleft of the protein. A3 is thus a potent inhibitor of FtsZ and shows potential to be used as a new antibacterial agent against drug-resistant bacteria.

Regulatory Effects of Damaged Renal Epithelial Cells After Repair by Porphyra yezoensis Polysaccharides with Different Sulfation Degree on the Calcium Oxalate Crystal-Cell Interaction.

BACKGROUND: The interaction between urinary microcrystals and renal epithelial cells is closely related to kidney stone formation. However, the mechanism of cell state changes that affect crystal-cell interaction remains unclear. METHODS: This study investigated the relationship between the sulfate group (-OSO3 -) content in Porphyra yezoensis polysaccharide (PYP) and the ability to repair damaged cells, as well as the changes in cell adhesion and endocytosis of nano-calcium oxalate monohydrate (COM) crystals before and after PYP repair of damaged renal tubular epithelial cells. The sulfur trioxide-pyridine method was used to sulfate PYP (-OSO3 - content of 14.14%), and two kinds of sulfated PYPs with -OSO3 - content of 20.28% (SPYP1) and 27.14% (SPYP2) were obtained. The above three PYPs were used to repair oxalate-damaged human proximal tubular epithelial cells (HK-2), and the changes in the biochemical indicators of the cells before and after the repair and the changes in cell adhesion and endocytosis of nano-COM crystals were detected. RESULTS: After repair by PYPs, the cell viability increased, the number of reactive oxygen species decreased, and the reduction of mitochondrial membrane potential and the release of intracellular Ca2+ were suppressed. The cells repaired by PYPs inhibited the adhesion of nano-COM crystals while promoting the endocytosis of the adhered crystals. The endocytosed crystals mainly accumulated in the lysosome. The ability of PYPs to repair cell damage, inhibit crystal adhesion, and promote crystal endocytosis was enhanced when the -OSO3 - content increased. Among them, SPYP2 with the highest -OSO3 - content showed the best biological activity. CONCLUSION: SPYP2 showed the best ability to repair damaged cells, followed by SPYP1 and PYP. SPYP2 may become a potential green drug that inhibits the formation and recurrence of calcium oxalate stones.

Microarray and Bioinformatics Analysis of Circular RNA Differential Expression in Newborns With Acute Respiratory Distress Syndrome.

Previous studies pointed out that a variety of microRNAs (miRNAs) are involved in the pathogenesis of neonatal acute respiratory distress syndrome (NARDS) and play different roles in the pathological process. However, there have been few studies reporting the connection between circular RNA (circRNA) and NARDS, so the expression profile of circRNAs in newborns with acute respiratory distress syndrome remains largely unknown. In the present study, 10 samples obtained from remaining clinical blood samples of newborns hospitalized in a neonatal ward of the First Affiliated Hospital of Nanjing Medical University from January 2020 to October 2020 were divided into the "NARDS" group and "non-NARDS" group according to the Montelux standard and then were analyzed in microarray, and 10 other samples collected from the same place and from January 1, 2021 to August 31, 2021, were used to do RT-qPCR experiment. circRNA expression profiles, in which 741 circRNAs were downregulated and 588 were upregulated, were screened with circRNA high-throughput sequencing. Subsequently, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis of parent genes of the differentially expressed circRNAs revealed that these circRNAs may be related to the process of protein synthesis and metabolism in NARDS. Moreover, five circRNAs-hsa_circ_0058495, hsa_circ_0000367, hsa_circ_0005389, hsa_circ_0059571, and hsa_circ_0006608-were selected randomly among the top 10 circRNAs of the downregulated or upregulated expression profiles. Then, bioinformatics tools were used to predict correlative miRNA and its target genes, which were also subjected to the same bioinformatics analysis for further study. The top 30 enriched KEGG pathway analyses of the 125 target genes suggested that these target genes are widely involved in the synthesis and secretion of endocrine hormones, and the top 30 enriched GO terms based on the 125 target genes are also focused on the protein and DNA processing. Thus, the present results show that circRNAs could promote the inflammation of NARDS which may provide a new therapeutic direction and it can be used as molecular markers for early diagnosis of NARDS, but further molecular biology verification is needed to define the specific role of differentially expressed circRNAs in NARDS.

Roundabout homolog 1 inhibits proliferation via the YY1-ROBO1-CCNA2-CDK2 axis in human pancreatic cancer.

Pancreatic cancer (PC) is highly malignant and has a high mortality with a 5-year survival rate of less than 8%. As a member of the roundabout immunoglobulin superfamily of proteins, ROBO1 plays an important role in embryogenesis and organogenesis and also inhibits metastasis in PC. Our study was designed to explore whether ROBO1 has effects on the proliferation of PC and its specific mechanism. The expression of ROBO1 was higher in cancer tissues than in matched adjacent tissues by immunohistochemistry (IHC) and qRT-PCR. Low ROBO1 expression is associated with PC progression and poor prognosis. Overexpression of ROBO1 can inhibit the proliferation of PC cells in vitro, and the S phase fraction can also be induced. Further subcutaneous tumor formation in nude mice showed that ROBO1 overexpression can significantly inhibit tumor growth. YY1 was found to directly bind to the promoter region of ROBO1 to promote transcription by a luciferase reporter gene assay, a chromatin immunoprecipitation (ChIP) and an electrophoretic mobility shift assay (EMSA). Mechanistic studies showed that YY1 can inhibit the development of PC by directly regulating ROBO1 via the CCNA2/CDK2 axis. Taken together, our results suggest that ROBO1 may be involved in the development and progression of PC by regulating cell proliferation and shows that ROBO1 may be a novel and promising therapeutic target for PC.

The study of 9,10-dihydroacridine derivatives as a new and effective molecular scaffold for antibacterial agent development.

The emergence of worldwide spreading drug-resistant bacteria has been a serious threat to public health during the past decades. The development of new and effective antibacterial agents to address this critical issue is an urgent action. In the present study, we investigated the antibacterial activity of two 9,10-dihydroacridine derivatives and their mechanism. Both compounds were found possessing strong antibacterial activity against some selected Gram-positive bacteria including MRSA, VISA and VRE. The biological study suggests that the compounds promoted FtsZ polymerization and also disrupted Z-ring formation at the dividing site and consequently, the bacterial cell division is interrupted and causing cell death.

Identification and pharmacokinetics of saponins in Rhizoma Anemarrhenae after oral administration to rats by HPLC-Q-TOF/MS and HPLC-MS/MS.

Rhizoma Anemarrhenae is a well-known herbal medicine with saponins as its commonly regarded major bioactive components. It is essential to classify the properties of saponins which are associated with their toxicity and efficacy. In this study, 25 compounds were identified by HPLC-Q-TOF/MS in the extract of Rhizoma Anemarrhenae and 8 saponins were detected in rat plasma by HPLC-MS/MS after oral administration of this extract. These were neomangiferin, mangiferin, timosaponin E1, timosaponin E, timosaponin B-II, timosaponin B-III, timosaponin A-III and timosaponin A-I. A sensitive and accurate HPLC-MS/MS method was developed and successfully applied to a pharmacokinetic study of the abovementioned eight saponins after oral administration of the Rhizoma Anemarrhenae extract to rats. The method validation, including specificity, linearity, precision, accuracy, recovery, matrix effect and robustness, met the requirements of the intended use. The pharmacokinetic parameter, T max value, ranged from 2 to 8 h for these eight saponins whereas their elimination half-life (t 1/2) ranged from 4.06 to 9.77 h, indicating slow excretion. The plasma concentrations of these eight saponins were all very low, indicating a relatively low oral bioavailability. All these results provide support for further clinical studies.

Biopharmaceutics and Pharmacokinetics of Timosaponin A-III by a Sensitive HPLC-MS/MS Method: Low Bioavailability Resulting from Poor Permeability and Solubility.

BACKGROUND: Timosaponin A-III is one of the most promising active saponins from Anemarrhena asphodeloides Bge. As an oral chemotherapeutic agent, there is an urgent need to clarify its biopharmaceutics and pharmacokinetics to improve its development potential. OBJECTIVE: This research explores the bioavailability of timosaponin A-III and clarifies its absorption and metabolism mechanisms by a sensitive and specific HPLC-MS/MS method. METHODS: Pharmacokinetics and bioavailability studies of timosaponin A-III were performed in Sprague- Dawley rats by oral (20 mg/kg) and intravenous administration (2 mg/kg). Control group was given the same volume of normal saline. The absorption of timosaponin A-III was investigated in a rat intestinal perfusion model in situ and a Caco-2 cell transport model in vitro. The metabolic rate of timosaponin A-III was determined in a rat liver microsome incubation system. RESULTS: After the oral administration, timosaponin A-III reached Cmax of 120.90 ± 24.97 ng/mL at 8 h, and the t1/2 was 9.94 h. The absolute oral bioavailability of timosaponin A-III was 9.18%. The permeability coefficients of timosaponin A-III in four intestinal segments ranged from 4.98 to 5.42 × 10-7 cm/s, indicating a difficult absorption. A strikingly high efflux transport of timosaponin A-III was found, PappBA 3.27 ± 0.64 × 10-6 cm/s, which was abolished by a P-gp inhibitor. Rat liver microsome incubation studies showed that timosaponin A-III could hardly be metabolized, with a t1/2 of over 12 h. In addition, the solubility test showed a low solubility in PBS solution, i.e. 30.58 µg/mL. CONCLUSION: Timosaponin A-III exhibited low oral bioavailability by oral and intravenous administration, which was probably caused by its low permeability and solubility. This study may provide a reference for its rational clinical use and further study on the pharmacology or toxicology of timosaponin A-III.

A small-sized benzothiazole-indolium fluorescent probe: the study of interaction specificity targeting c-MYC promoter G-quadruplex structures and live cell imaging.

A small-sized c-MYC promoter G-quadruplex selective fluorescent BZT-Indolium binding ligand was demonstrated for the first time as a highly target-specific and photostable probe for in vitro staining and live cell imaging and it was found to be able to inhibit the amplification of the c-MYC G-rich sequence (G-quadruplex) and down-regulate oncogene c-MYC expression in human cancer cells (HeLa).

Linc01232 promotes the metastasis of pancreatic cancer by suppressing the ubiquitin-mediated degradation of HNRNPA2B1 and activating the A-Raf-induced MAPK/ERK signaling pathway.

Pancreatic cancer (PC) is a malignant cancer with high mortality and poor prognosis. In this study, we found that Linc01232 was significantly upregulated in PC tissues and cells and higher Linc01232 expression was associated with poorer prognosis. Linc01232 overexpression promoted and Linc01232 knockdown inhibited the migration and invasion of PC cells. The results of RNA pull-down, RNA Binding Protein Immunoprecipitation (RIP) assays revealed that Linc01232 physically interacted with Heterogeneous Nuclear Ribonucleoprotein A2/B1 (HNRNPA2B1) (680-890 nt fragment with the RNA recognition motif 2 domain) to inhibit its ubiquitin-mediated degradation in PC cells. RNA sequencing was performed to obtain the transcriptional profiles regulated by Linc01232 and we further demonstrated that Linc01232 participated in the alternative splicing of A-Raf by stabilizing HNRNPA2B1 and subsequently regulated the MAPK/ERK signaling pathway. Collected, our study showed that Linc01232/HNRNPA2B1/A-Raf/MAPK axis participated in the progression of PC and provided a potential therapeutic target for PC.

Identification of a novel BACE1 inhibitor, timosaponin A-III, for treatment of Alzheimer's disease by a cell extraction and chemogenomics target knowledgebase-guided method.

BACKGROUND: Rhizoma Anemarrhenae (RA) has been conventionally used for treatment of Alzheimer's disease (AD) in Traditional Chinese Medicine, and thus, the active components from RA can be screened. PURPOSE: This research aimed to identify the active components of RA and their targets and further clarify the molecular mechanisms underlying its anti-AD activity. METHODS: First, the potential active compounds from RA were screened by neurocyte extraction and micro-dialysis methods. Second, the potential targets were predicted by a chemogenomics target knowledgebase and further explored by surface plasmon resonance and enzyme activity assays. Third, the pharmacological effects were evaluated by employing APP/PS1 transgenic mice and SH-SY5Y-APP cells. ELISAs and Western blot analyses were used to evaluate the expression of key molecules in the amyloidogenic and NMDAR/ERK pathways. RESULTS: Timosaponin A-III (TA-III) was screened and identified as a potential active component for the anti-AD activity, and BACE1 was proven to be a potential high-affinity target. Enzyme kinetic analysis showed that TA-III had strong noncompetitive inhibitory activity against BACE1. The in vitro and in vivo assays indicated that TA-III had pharmacological effects through improving memory impairment, reducing Aß aggregation via the amyloidogenic pathway and preventing neuronal impairment through downregulating the NMDAR/ERK signaling pathway. CONCLUSION: TA-III targets BACE1 to reduce Aß aggregation through down-regulating the NMDAR/ERK pathway for treating AD.