Hydroxylated hierarchical flower-like COF for solid-phase extraction of adrenergic receptor agonists in milk.

A new detection platform based on a hydroxylated covalent organic framework (COF) integrated with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was constructed and used for detecting adrenergic receptor agonists (ARAs) residues in milk. The hydroxylated COF was prepared by polymerization of tris(4-aminophenyl)amine and 1,3,5-tris(4-formyl-3-hydroxyphenyl)benzene and applied to solid-phase extraction (SPE) of ARAs. This hydroxylated COF was featured with hierarchical flower-like morphology, easy preparation, and copious active adsorption sites. The adsorption model fittings and molecular simulation were applied to explore the potential adsorption mechanism. This detection platform was suitable for detecting four α2- and five ß2-ARAs residues in milk. The linear ranges of the ARAs were from 0.25 to 50 µg·kg-1; the intra-day and the inter-day repeatability were in the range 2.9-7.9% and 2.0-10.1%, respectively. This work demonstrates this hydroxylated COF has great potential as SPE cartridge packing, and provides a new way to determine ARAs residues in milk.

Synthesis and antitumor activity of dolutegravir derivatives bearing 1,2,3-triazole moieties.

Modification of marketed drugs is an important way to develop drugs because its safety and clinical applicability. Oxygen-nitrogen heterocycles are a class of important active substances discovered in the process of new drug development. Dolutegravir, an HIV drug with a nitrogen-oxygen heterocycle structure, has the potential ability to inhibit cell survival. In order to find and explore novel anti-tumor drugs, new dolutegravir derivatives bearing different 1,2,3-triazole moieties were prepared via click reactions. In vitro biological experiments performed in several lung cancer cell lines suggested that these novel compounds displayed potent anti-tumor ability. Especially, the compound 9e with a substituent of 2-methyl-3-nitrophenyl and the compound 9p with a substituent of 3-trifluoromethylphenyl were effective against PC-9 cell line with IC50 values of 3.83 and 3.17 µM, respectively. Moreover, compounds 9e and 9p were effective against H460 and A549 cells. Further studies suggested that compounds 9e and 9p could induce cancer cell apoptosis in PC-9 and H460, inhibit cancer cell proliferation, change the cell cycle, and increase the level of reactive oxygen species (ROS) which further induce tumor cell apoptosis. In addition, compounds 9e and 9p increased LC3 protein expression which was the key regulator in autophagy signaling pathway in PC-9 cells. Compound 9e also showed low toxicity against normal cells, and could be regarded as an interesting lead compound for further structure optimization.

Development of Glycosylation-Modified DPPA-1 Compounds as Innovative PD-1/PD-L1 Blockers: Design, Synthesis, and Biological Evaluation.

In the context of peptide drug development, glycosylation plays a pivotal role. Accordingly, L-type peptides were synthesized predicated upon the PD-1/PD-L1 blocker DPPA-1. Subsequent glycosylation resulted in the production of two distinct glycopeptides, D-glu-LPPA-1 and D-gal-LPPA-1, by using D-glucose (D-glu) and D-galactose (D-gal), respectively, during glycosylation. Both glycopeptides significantly inhibited the interaction between PD-1 and PD-L1, and the measured half maximal inhibitory concentrations (IC50s) were 75.5 µM and 101.9 µM for D-glu-LPPA-1 and D-gal-LPPA-1, respectively. Furthermore, D-gal-LPPA-1 displayed a pronounced ability to restore T-cell functionality. In an MC38 tumor-bearing mouse model, D-gal-LPPA-1 demonstrated a significant inhibitory effect. Notably, D-gal-LPPA-1 substantially augmented the abundance and functionality of CD8+ T cells in the tumor microenvironment. Additionally, in the lymph nodes and spleens, D-gal-LPPA-1 significantly increased the proportion of CD8+ T cells secreting interferon-gamma (IFN-γ). These strong findings position D-gal-LPPA-1 as a potent enhancer of the antitumor immune response in MC38 tumor-bearing mice, underscoring its potential as a formidable PD-1/PD-L1 blocking agent.

Trichoderma hamatum and Its Benefits.

Trichoderma hamatum (Bonord.) Bainier (T. hamatum) belongs to Hypocreaceae family, Trichoderma genus. Trichoderma spp. are prominently known for their biocontrol activities and plant growth promotion. Hence, T. hamatum also possess several beneficial activities, such as antimicrobial activity, antioxidant activity, insecticidal activity, herbicidal activity, and plant growth promotion; in addition, it holds several other beneficial properties, such as resistance to dichlorodiphenyltrichloroethane (DDT) and degradation of DDT by certain enzymes and production of certain polysaccharide-degrading enzymes. Hence, the current review discusses the beneficial properties of T. hamatum and describes the gaps that need to be further considered in future studies, such as T. hamatum's potentiality against human pathogens and, in contrast, its role as an opportunistic human pathogen. Moreover, there is a need for substantial study on its antiviral and antioxidant activities.

A dual-mode nanoprobe based on silicon nanoparticles and Fe(II)-phenanthroline for the colorimetric and fluorescence determination of nitrite.

A fluorometric and colorimetric dual-modal nanoprobe (denoted as Fe2+-Phen/SiNPs) has been developed for selective and sensitive determination of nitrite (NO2-). The mechanism is based on fluorescence quenching between silicon nanoparticles (SiNPs) and Fe(II)-phenanthroline complex (Fe2+-Phen) via inner filter effect and redox. With the addition of increasing NO2-, Fe2+ is oxidized to Fe3+, recovering the fluorescence of SiNPs. Meanwhile, the color of the system gradually changes from orange-red to colorless, which enables colorimetric measurement. The NO2- concentration shows a wide linear relationship with fluorescence intensity from 0.1 to 1.0 mM (R2 = 0.9955) with a detection limit of 2.4 µM in the fluorometric method (excitation wavelength: 380 nm). By contrast, the linear range of the colorimetric method ranges from 0.01 to 0.35 mM (R2 = 0.9953) with a limit of detection of 6.8 µM (proposed selective absorbance: 510 nm). The probe has been successfully applied to nitrite determination in water, salted vegetables, and hams demonstrating broad application prospects for the determination of nitrite in complicated matrices.

Improved anti-tumor activity of fluorinated camptothecin derivatives 9-fluorocamptothecin and 7-ethyl-9-fluorocamptothecin on hepatocellular carcinoma by targeting topoisomerase I.

Primary liver cancer is one of the most common malignant cancers of the digestive system that lacks effective chemotherapeutic drugs in clinical settings. Camptothecin (CPT) and its derivatives have been approved for cancer treatment; however, their application is limited by their systemic toxicity. For lead optimization in new drug discovery stages, fluorination is an effective and robust approach to increase the bioavailability and optimize the pharmacokinetics of candidate compounds, thereby improving their efficacy. To obtain new and highly active CPT derivatives, we designed, synthesized, and evaluated two new fluorinated CPT derivatives, 9-fluorocamptothecin (A1) and 7-ethyl-9-fluorocamptothecin (A2), in this study. In vitro, A1 and A2 exhibited more robust anti-tumor activity than topotecan (TPT) in various cancer cells, particularly hepatocellular carcinoma (HCC) cells. In vivo, A1 and A2 exhibited greater anti-tumor activity than TPT in both AKT/Met induced primary HCC mouse models and implanted HepG2 cell xenografts. Acute toxicity tests revealed that A1 and A2 were not lethal and did not cause significant body weight loss at high doses. Moreover, A1 and A2 exhibited no significant toxicity in the mouse liver, heart, lung, spleen, kidney, and hematopoietic systems at therapeutic doses. Mechanistically, A1 and A2 blocked HCC cell proliferation by inhibiting the enzymatic activity of Topo I, subsequently inducing DNA damage, cell cycle arrest, and apoptosis. In summary, our results indicate that fluorination improves the anti-tumor activity of CPT while decreasing its toxicity and highlight the application potential of fluorination products A1 and A2 in clinical settings.

Antimicrobial activity and enzymatic analysis of endophytes isolated from Codonopsis pilosula.

The roots of the medicinal plant Codonopsis pilosula (Franch.) Nannf (C. pilosula) possess most medicinal supplements. In current research on C. pilosula root endophytes were isolated, identified, and evaluated for their antimicrobial activity against human pathogens such as Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Salmonella typhi, and Pseudomonas aeruginosa and the fungi Candida albicans and Aspergillus niger. Endophytes C.P-8 and C.P-20 exhibited very significant antimicrobial activity, the secondary metabolite of C.P-8 registered at retention time 24.075 by HPLC analysis. Significant minimum inhibitory concentration (MIC) of C.P-8 was exhibited at 250 µg/ml against S. aureus and 500 µg/ml against B. subtilis. Qualitative, quantitative analyses, and partial purification of enzymes and purity was analysed by molecular weight determined by SDS‒PAGE of enzymes produced by C.P-20, amylase-64 kDa, protease-64 kDa, chitinase-30 kDa, and cellulase-54 kDa. Optimum pH and temperature of the partially purified enzymes, was carried out. The partially purified enzymes from C.P-20 displayed maximum activity at pH 6-7 and temperatures of 40°C-45°C. Moreover, the above endophytes will be useful tools for producing active enzymes and active bioantimicrobial agents against human pathogens.

Decoding the enhanced antioxidant activities of the combined small berry pomaces by widely targeted metabolomics analysis.

Small berry pomaces (SBPs) are poorly utilized as an inexpensive source of bioactive compounds. This study investigated the impact of compounding treatment on nutritional and antioxidant characteristics of combined SBPs, in comparison with single SBP. The results showed that the amounts of protein, minerals, dietary fiber (DF) and anthocyanidins were significantly (p < 0.05) higher in combined SBPs than in combined fruits. Moreover, the combined SBPs were characterized by an elevated abundance of minerals and anthocyanidins (6 kinds, and 5 kinds, respectively), substantiating the effectiveness of compounding treatment on SBP nutrition. A total of 776 secondary phytochemicals were detected in combined SBPs by a widely targeted metabolomics approach. Each SBP contained approximately 100 kinds of unique natural antioxidants. Furthermore, the combined SBPs group had the highest antioxidant activity compared with single SBP. Meanwhile, the antioxidant activities determined in combined SBPs were higher than arithmetic mean value of single SBP. The synergism and interaction of active components in different sources of SBPs play vital role in the high antioxidant capacity of combined SBPs. All the results provide reference for the comprehensive development and utilization of fruit residues. The SBPs should be highly prized for their substantial amount of nutritional and bioactive constituents, including protein, DF, essential minerals and secondary metabolites. These secondary metabolites are positively associated with antioxidant benefits. The present study summarizes the knowledge about bioactive compounds and antioxidant activities of combined SBPs group and discusses the relevant mechanisms. A conclusion can be educed that combined process is an effective way to improve properties of the pomaces.

Synthesis and Anti-Tumor Effects of Novel Pomalidomide Derivatives Containing Urea Moieties.

In order to explore novel immunomodulatory agents as anti-tumor drugs, we designed and synthesized a series of new pomalidomide derivatives containing urea moieties. Interestingly, in vitro biological experiments performed in several cancer cell lines showed that some of them displayed potent anti-tumor ability. These novel compounds 5a-5e and 6a-6e demonstrated the best cell growth inhibitive activity in human breast cancer cell lines MCF-7, but weaker inhibitive activity in human hepatocellular carcinoma cell lines Huh7. Moreover, compound 5d had the most powerful effects in this study, with an IC50 value of 20.2 µM in MCF-7. Further study indicated that compound 5d could inhibit cell growth and induce cell death in a concentration-dependent manner. Besides, compound 5d increased cellular ROS levels and induced DNA damage, thereby potentially leading to cell apoptosis. These observations suggest that the novel pomalidomide derivatives containing urea moieties may be worth further investigation to generate potential anti-tumor drugs.

Selenium-Modified Chitosan Induces HepG2 Cell Apoptosis and Differential Protein Analysis.

Introduction: Chitosan is the product of the natural polysaccharide chitin removing part of the acetyl group, and exhibits various physiological and bioactive functions. Selenium modification has been proved to further enhance the chitosan bioactivities, and has been a hot topic recently. Methods: The present study aimed to investigate the potential inhibitory mechanism of selenium-modified chitosan (SMC) on HepG2 cells through MTT assays, morphological observation, annexin V-FITC/PI double staining, mitochondrial membrane potential determination, cell-cycle detection, Western blotting, and two-dimensional gel electrophoresis (2-DE). Results: The results indicated that SMC can induce HepG2 cell apoptosis with the cell cycle arrested in the S and G2/M phases and gradual disruption of mitochondrial membrane potential, reduce the expression of Bcl2, and improve the expression of Bax, cytochrome C, cleaved caspase 9, and cleaved caspase 3. Also, 2-DE results showed that tubulin α1 B chain, myosin regulatory light chain 12A, calmodulin, UPF0568 protein chromosome 14 open reading frame 166, and the cytochrome C oxidase subunit 5B of HepG2 cells were downregulated in HepG2 cells after SMC treatment. Discussion: These data suggested that HepG2 cells induced apoptosis after SMC treatment via blocking the cell cycle in the S and G2/M phases, which might be mediated through the mitochondrial apoptotic pathway. These results could be of benefit to future practical applications of SMC in the food and drug fields.

Anti-tumor effects and mechanism of a novel camptothecin derivative YCJ100.

AIMS: In this study, we synthesized a 10-fluorine-substitution derivative of CPT (Camptothecin) YCJ100 and evaluated its antitumor activity and systemic toxicity. MATERIALS AND METHODS: Determination of in vitro antitumor activity and mechanism of YCJ100 by the MTT assay, Molecular docking, EdU staining, Cell cycle and apoptosis determination, Western blot analysis and Topoisomerase I activity assay. The antitumor effects of YCJ100 were evaluated in primary HCC (hepatocellular carcinoma), ICC (intrahepatic cholangiocarcinoma) mouse models, and pancreatic cancer xenograft models. KEY FINDINGS: YCJ100 showed superior cytotoxic activity compared to Topotecan in SW480, SW1990, Hep3B, HepG2, A549, A2780, HeLa, and QBC cells. YCJ100 blocked the cell cycle in the G2/M phase, inhibited cell proliferation and induced apoptosis in HepG2 and SW1990 cells. Mechanistically, YCJ100 inhibited topoisomerase I activity in both a cell-free system and a cellular system, similar to the mechanism of Topotecan. YCJ100 showed significant antitumor activity and was more potent than Topotecan in primary HCC and ICC mouse models, as well as a xenograft mouse model. Additionally, YCJ100 showed only minor toxicity to the mouse hematopoietic system, liver, and kidney. These findings indicate that YCJ100 has high antitumor activity and low systemic toxicity. SIGNIFICANCE: Our findings demonstrate that YCJ100, as a Topoisomerase I inhibitor, has in vitro and in vitro antitumor activity. This study provides a new lead compound worthy of further preclinical evaluation and potential clinical development.

Extraction, Structure and Immunoregulatory Activity of Low Molecular Weight Polysaccharide from Dendrobium officinale.

The ethanol precipitation method has been widely-used for Dendrobium officinale polysaccharides preparation. However, the alcohol-soluble fractions have always been ignored, which causes significant wastes of resources and energies. In this study, the extraction, physicochemical properties, and immune regulation activity of an edible D. officinale polysaccharide (DOPs) isolated from the supernatant after 75% ethanol precipitation were systematically investigated. The structural characteristics determination results showed that DOPs was mainly composed of glucose and mannose at a molar ratio of 1.00:5.78 with an average molecular weight of 4.56 × 103 Da, which was made up of α-(1,3)-Glcp as the main skeleton, and the α-(1,4)-Glcp and ß-(1,4)-Manp as the branches. Subsequently, the cyclophosphamide (CTX)-induced immunosuppressive mice model was established, and the results demonstrated that DOPs could dose-dependently protect the immune organs against CTX damage, improve the immune cells activities, and promote the immune-related cytokines (IL-2, IFN-γ and TNF-α) secretions. Furthermore, DOPs treatment also effectively enhanced the antioxidant enzymes levels (SOD, GSH-Px) in sera and livers, therefore weakening the oxidative damage of CTX-treated mice. Considering these above data, DOPs presented great potential to be explored as a natural antioxidant and supplement for functional foods.

Novel 1,2,3-Triazole Erlotinib Derivatives as Potent IDO1 Inhibitors: Design, Drug-Target Interactions Prediction, Synthesis, Biological Evaluation, Molecular Docking and ADME Properties Studies.

Indoleamine 2,3-dioxygenase 1 (IDO1) plays a predominant role in cancer immunotherapy which catalyzes the initial and rate limiting steps of the kynurenine pathway as a key enzyme. To explore novel IDO1 inhibitors, five derivatives of erlotinib-linked 1,2,3-triazole compounds were designed by using a structure-based drug design strategy. Drug-target interactions (DTI) were predicted by DeePurpose, an easy-to-use deep learning library that contains more than 50 algorithms. The DTI prediction results suggested that the designed molecules have potential inhibitory activities for IDO1. Chemical syntheses and bioassays showed that the compounds exhibited remarkable inhibitory activities against IDO1, among them, compound e was the most potent with an IC50 value of 0.32 ± 0.07 µM in the Hela cell assay. The docking model and ADME analysis exhibited that the effective interactions of these compounds with heme iron and better drug-likeness ensured the IDO1 inhibitory activities. The studies suggested that compound e was a novel and interesting IDO1 inhibitor for further development.

Discovery of Novel HPK1 Inhibitors Through Structure-Based Virtual Screening.

Hematopoietic progenitor kinase (HPK1) is a negative regulator of T-cell receptor and B-cell signaling, which has been recognized as a novel antitumor target for immunotherapy. In this work, Glide docking-based virtual screening and kinase inhibition assay were performed to identify novel HPK1 inhibitors. The kinase inhibition assay results demonstrated five compounds with IC50 values below 20 µM, and the most potent one (compound M074-2865) had an IC50 value of 2.93 ± 0.09 µM. Molecular dynamics (MD) simulations were performed to delve into the interaction of sunitinib and the identified compound M074-2865 with the kinase domain of HPK1. The five compounds identified in this work could be considered promising hit compounds for further development of HPK1 inhibitors for immunotherapy.

Discovery of a Series of Theophylline Derivatives Containing 1,2,3-Triazole for Treatment of Non-Small Cell Lung Cancer.

Chemotherapy is the most common clinical treatment for non-small cell lung cancer (NSCLC), but low efficiency and high toxicity of current chemotherapy drugs limit their clinical application. Therefore, it is urgent to develop hypotoxic and efficient chemotherapy drugs. Theophylline, a natural compound, is safe and easy to get, and it can be used as a modified scaffold structure and hold huge potential for developing safe and efficient antitumor drugs. Herein, we linked theophylline with different azide compounds to synthesize a new type of 1,2,3-triazole ring-containing theophylline derivatives. We found that some theophylline1,2,3-triazole compounds showed a good tumor-suppressive efficacy. Especially, derivative d17 showed strong antiproliferative activity against a variety of cancer cells in vitro, including H460, A549, A2780, LOVO, MB-231, MCF-7, OVCAR3, SW480, and PC-9. It is worth noting that the two NSCLC cell lines H460 H and A549 are sensitive to compound d17 particularly, with IC50 of 5.929 ± 0.97 µM and 6.76 ± 0.25 µM, respectively. Compound d17 can significantly induce cell apoptosis by increasing the ratio of apoptotic protein Bax/Bcl-2 by downregulating the expression of phosphorylated Akt protein, and it has little toxicity to normal hepatocyte cells LO2 at therapeutic concentrations. These data indicate that these theophylline acetic acid-1,2,3-triazole derivatives may be potential drug candidates for anti-NSCLC and are worthy of further study.

Synthesis and Antitumor Activity of Erlotinib Derivatives Linked With 1,2,3-Triazole.

Cervical cancer is one of the most important cause of cancer-related death and presents a major public health problem in many countries. To search for more novel antitumor agents against cervical cancer, 14 erlotinib-linked 1,2,3-triazole compounds were designed, synthesized, and evaluated for their anti-tumor activity. The compounds were confirmed by 1H NMR, 13C NMR, and high-resolution mass spectra (HR MS). Antitumor activity assay results indicated that six of those compounds have remarkable inhibitory activity against human cervical cancer HeLa cells in vitro, among which compound 4m was the most potent with IC50 of 3.79 µM, and compounds 4k, 4i, 4l, 4d, and 4n also demonstrated remarkable antitumor activity with IC50 of 3.79, 4.16, 4.36, 7.02, and 8.21 µM. We found three of the most potent compounds 4d, 4k, and 4l induced potent apoptosis and cell cycle arrest in HeLa cells, and compounds 4d and 4l significantly restrained the cell colony formation and showed moderate epidermal growth factor receptor (EGFR) inhibitory activity with IC50 of 13.01 and 1.76 µM. Therefore, these experiments indicate that these erlotinib-linked 1,2,3-triazole compounds are potential to act as effective anticancer agents against cervical cancer.

Synthesis and activity of novel indirubin derivatives.

A series of indirubin derivatives hydrochloride were obtained using a convenient and mild method from indirubin. The newly synthesized compounds and their derivatives were characterized by 1 H NMR, 13 C NMR, and MS. Furthermore, we tested their IDO1 enzyme inhibitory activity and anti-proliferative activities in K562 tumor cells. The experimental results revealed that some of the compounds showed potential anti-enzyme and anti-tumor activity. Among of them, compound 4b exhibited certain inhibitory activity on IDO1 (IC50 : 29.52 µmol/L), and compound 4a displayed activity similar to indirubin in K562 tumor cells (IC50 : 24.96 µmol/L). This type of indirubin derivative is expected to have the potential to act as an immunologically active anti-tumor drug, indicating that further research will be worthwhile.

Dynamic and Antagonistic Allele-Specific Epigenetic Modifications Controlling the Expression of Imprinted Genes in Maize Endosperm.

Genomic imprinting is often associated with allele-specific epigenetic modifications. Although many reports suggested potential roles of DNA methylation and H3K27me3 in regulating genomic imprinting, the contributions of allele-specific active histone modifications to imprinting remain still unclear in plants. Here, we report the identification of 337 high-stringency allele-specific H3K4me3 and H3K36me3 peaks in maize endosperm. Paternally preferred H3K4me3 and H3K36me3 peaks mostly co-localized with paternally expressed genes (PEGs), while endosperm-specific maternally expressed genes (endo-MEGs) were associated with maternally preferred H3K4me3 and H3K36me3 peaks. A unique signature for PEGs was observed, where the active H3K4me4 and H3K36me3 as well as repressive H3K27me3 appeared together. At the gene body of con-PEGs (constitutively expressed PEG), H3K27me3 and H3K36me3 were specifically deposited on hypomethylated maternal alleles and hypermethylated paternal alleles, respectively. Around the transcription start sites of endo-MEGs, DNA methylation and H3K4me3 specifically marked paternal and maternal alleles, respectively. In addition, 35 maternally expressed non-coding RNAs exhibited the same allele-specific epigenetic features as endo-MEGs, indicating similar mechanisms for the regulation of imprinted genes and non-coding RNAs. Taken together, our results uncover the complex patterns of mutually exclusive epigenetic modifications deposited at different alleles of imprinted genes that are required for genomic imprinting in maize endosperm.

Ribosome profiling reveals dynamic translational landscape in maize seedlings under drought stress.

Plants can respond to environmental changes with various mechanisms occurred at transcriptional and translational levels. Thus far, there have been relatively extensive understandings of stress responses of plants on transcriptional level, while little information is known about that on translational level. To uncover the landscape of translation in plants in response to drought stress, we performed the recently developed ribosome profiling assay with maize seedlings growing under normal and drought conditions. Comparative analysis of the ribosome profiling data and the RNA-seq data showed that the fold changes of gene expression at transcriptional level were moderately correlated with that of translational level globally (R(2) = 0.69). However, less than half of the responsive genes were shared by transcription and translation under drought condition, suggesting that drought stress can introduce transcriptional and translational responses independently. We found that the translational efficiencies of 931 genes were changed significantly in response to drought stress. Further analysis revealed that the translational efficiencies of genes were highly influenced by their sequence features including GC content, length of coding sequences and normalized minimal free energy. In addition, we detected potential translation of 3063 upstream open reading frames (uORFs) on 2558 genes and these uORFs may affect the translational efficiency of downstream main open reading frames (ORFs). Our study indicates that plant can respond to drought stress with highly dynamic translational mechanism, that acting synergistically with that of transcription.