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1.
Gels ; 10(6)2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38920959

ABSTRACT

To realize the effective profile control of a heavy oil reservoir, hydrolyzed polyacrylamide (HPAM) and water-soluble phenol-formaldehyde resin (PR) were chosen to prepare the profile control system, which gelled at medium or low temperatures and existed stably at high temperatures in the meantime. The effects of phenolic ratios, PR concentration, and HPAM concentration on the formation and strength of the gels were systematically studied by the gel-strength code method and rheological measurements. And the microstructure of the gels was investigated by scanning electron microscope measurements. The results showed that the gelling time of the HPAM-PR system was 13 h at 70 °C. The formed gel could stay stable for 90 days at 140 °C. In addition, the gels showed viscoelastic properties, and the viscosity reached 18,000 mPa·s under a 1.5 s-1 shearing rate due to their three-dimensional cellular network structure. The formation of the gels was attributable to the hydroxyl groups of the PR crosslinking agent, which could undergo the dehydration condensation reaction with amide groups under non-acidic conditions and form intermolecular crosslinking with HPAM molecules. And the organic crosslinker gel system could maintain stability at higher temperatures because covalent bonds formed between molecules.

2.
J Chromatogr A ; 1728: 464986, 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-38797137

ABSTRACT

In this study, a novel at-line nanofractionation platform was established for screening SARS-CoV-2 fusion inhibitors from natural products for the first time by combining HPLC-MS/MS with high-throughput fluorescence polarization (FP) bioassay. A time-course FP bioassay in 384 well-plates was conducted in parallel with MS/MS to simultaneously obtain chemical and biological information of potential fusion inhibitors in Lonicerae Japonicae Flos (LJF) and Lianhua Qingwen capsules (LHQW). Semi-preparative liquid chromatography and orthogonal HPLC separation were employed to enrich and better identify the co-eluted components. After comprehensive evaluation and validation, 28 potential SARS-CoV-2 fusion inhibitors were screened out and identified. Several compounds at low micromolar activity were validated by in vitro inhibitory assay, molecular docking, cytotoxicity test, and pseudovirus assay. Moreover, four potential dual-target inhibitors against influenza and COVID-19 were discovered from LJF using this method, offering novel insights for the development of future pharmaceuticals targeting epidemic respiratory diseases.


Subject(s)
Antiviral Agents , Fluorescence Polarization , Molecular Docking Simulation , SARS-CoV-2 , Tandem Mass Spectrometry , Chromatography, High Pressure Liquid/methods , SARS-CoV-2/drug effects , Tandem Mass Spectrometry/methods , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/analysis , Humans , Fluorescence Polarization/methods , High-Throughput Screening Assays/methods , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/chemistry , Lonicera/chemistry , COVID-19/virology , Liquid Chromatography-Mass Spectrometry
3.
J Chromatogr A ; 1722: 464896, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38631224

ABSTRACT

In this study, a novel magnetic bead-based ligand fishing method was developed for rapid discovery of monoterpene indoles as monoamine oxidase A inhibitors from natural products. In order to improve the screening efficiency, two different magnetic beads, i.e. amine and carboxyl terminated magnetic beads, were comprehensively compared in terms of their ability to immobilize monoamine oxidase A (MAOA), biocatalytic activity and specific adsorption rates for affinity ligands. Carboxyl terminated magnetic beads performed better for MAOA immobilization and demonstrated superior performance in ligand fishing. The MAOA immobilized magnetic beads were applied to screen novel monoamine oxidase inhibitors in an alkaloid-rich plant, Hunteria zeylanica. Twelve MAOA affinity ligands were screened out, and ten of them were identified as monoterpene indole alkaloids by HPLC-Obitrap-MS/MS. Among them, six ligands, namely geissoschizol, vobasinol, yohimbol, dihydrocorynanthenol, eburnamine and (+)-isoeburnamine which exhibited inhibitory activity against MAOA with low IC50 values. To further explore their inhibitory mechanism, enzyme kinetic analysis and molecular docking studies were conducted.


Subject(s)
Molecular Docking Simulation , Monoamine Oxidase Inhibitors , Monoamine Oxidase , Monoamine Oxidase Inhibitors/chemistry , Monoamine Oxidase Inhibitors/pharmacology , Monoamine Oxidase Inhibitors/isolation & purification , Monoamine Oxidase/metabolism , Monoamine Oxidase/chemistry , Ligands , Indoles/chemistry , Monoterpenes/chemistry , Monoterpenes/isolation & purification , Kinetics , Tandem Mass Spectrometry/methods , Chromatography, High Pressure Liquid/methods , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Enzymes, Immobilized/antagonists & inhibitors , Humans , Plant Extracts/chemistry
4.
Acta Pharm Sin B ; 14(4): 1772-1786, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38572096

ABSTRACT

Human monoamine oxidase B (hMAO-B) has emerged as a pivotal therapeutic target for Parkinson's disease. Due to adverse effects and shortage of commercial drugs, there is a need for novel, highly selective, and reversible hMAO-B inhibitors with good blood-brain barrier permeability. In this study, a high-throughput at-line nanofractionation screening platform was established with extracts from Chuanxiong Rhizoma, which resulted in the discovery of 75 active compounds, including phenolic acids, volatile oils, and phthalides, two of which were highly selective novel natural phthalide hMAO-B inhibitors that were potent, selective, reversible and had good blood‒brain permeability. Molecular docking and molecular dynamics simulations elucidated the inhibition mechanism. Sedanolide (IC50 = 103 nmol/L; SI = 645) and neocnidilide (IC50 = 131 nmol/L; SI = 207) demonstrated their excellent potential as hMAO-B inhibitors. They offset the limitations of deactivating enzymes associated with irreversible hMAO-B inhibitors such as rasagiline. In SH-SY5Y cell assays, sedanolide (EC50 = 0.962 µmol/L) and neocnidilide (EC50 = 1.161 µmol/L) exhibited significant neuroprotective effects, comparable to the positive drugs rasagiline (EC50 = 0.896 µmol/L) and safinamide (EC50 = 1.079 µmol/L). These findings underscore the potential of sedanolide as a novel natural hMAO-B inhibitor that warrants further development as a promising drug candidate.

5.
Int Immunopharmacol ; 124(Pt A): 110905, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37717372

ABSTRACT

Anti-PD-1/PD-L1 monoclonal antibodies have displayed remarkable clinical benefits and revolutionized the treatment of multiple tumor types, but the low response rates and immune-related adverse events limit their application, which promoting the development of small molecule agents to improve the efficacy of PD-1/PD-L1 blockade therapy. Boningmycin (BON), a new small molecule belonging to bleomycin (BLM) family, exhibits potent anticancer activity in vitro and in vivo, as well as negligible lung toxicity, thereby can be an alternative of BLM. However, understandings about the anticancer mechanism of BLM-related compounds are extremely rare, it remains unclear if they affect PD-L1 level in a manner similar to that of other antitumor drugs. In this study, we discover that BON significantly reduces PD-L1 protein level in NCI-H460 and HT-1080 cells. Meanwhile, BON decreases the protein level of PD-L1 in a tumor xenograft model of NCI-H460 cells. Nevertheless, the mRNA level is not influenced after BON exposure. Furthermore, BON-induced PD-L1 reduction is proteasome- dependent. By using specific inhibitors and RNA interference technology, we confirm that the decline of PD-L1 protein by BON is mediated by AMPK-activated endoplasmic reticulum-associated degradation pathway, which is like to the action of metformin. Last but not the least, BON has synergism on gefitinib in vitro and in vivo. In conclusion, it is the first report demonstrating that BON decreases PD-L1 protein level through AMPK-mediated endoplasmic reticulum-associated degradation pathway. These findings will benefit the clinical transformation of BON and aid in the elucidation of molecular mechanism of BLM-related compounds.


Subject(s)
B7-H1 Antigen , Neoplasms , Humans , B7-H1 Antigen/metabolism , Endoplasmic Reticulum-Associated Degradation , AMP-Activated Protein Kinases/metabolism , Neoplasms/drug therapy , Bleomycin/metabolism , Antibodies, Monoclonal/therapeutic use , Cell Line, Tumor
6.
Org Lett ; 25(33): 6116-6121, 2023 08 25.
Article in English | MEDLINE | ID: mdl-37578318

ABSTRACT

We herein reported a new type of S-o-(p-methoxyphenylethynyl)benzyl donor for a highly efficient glycosylation method. The donor was activated by 10% Tf2O and underwent glycosylation with various acceptors to provide the corresponding glycosides in excellent yield. Furthermore, two repetitive fragments of Polyporus umbellatus polysaccharides (PUPs), isolated from traditional Chinese medicine "Polyporus umbellatus", were prepared by combining the "single-catalyst one-pot" and "latent-active" strategies for the first time for future clear studies on the structure-activity relationship of PUPs.


Subject(s)
Polyporus , Glycosylation , Glycosides , Polysaccharides
7.
J Chromatogr A ; 1691: 463817, 2023 Feb 22.
Article in English | MEDLINE | ID: mdl-36738572

ABSTRACT

In this study, an at-line nanofractionation (ANF) platform was successfully fabricated in parallel with mass spectrometry and trypsin inhibitory bioactivity assessment for rapid screening of trypsin inhibitors (TIs) from natural products for the first time. After systematic optimization, the ANF platform was applied to screen and identify TIs in the extract of a traditional Chinese herb, i.e., Cotinus coggygria Scop. The semi-preparative reverse-phase liquid chromatography was used subsequently to further simplify and enrich the insufficiently separated components. After comprehensive evaluation and validation, the ANF platform successfully identified 12 compounds as potential TIs, including 8 flavonoids and 2 organic acids. Additionally, a comparison study was conducted using two other ligand fishing approaches, i.e., capillary monolithic and magnetic beads-based trypsin-immobilized enzyme microreactors, which successfully identified 8 identical flavonoids as TIs. Importantly, the molecular docking study showed the molecular interactions between enzymes and inhibitors, thus strongly supporting the experimental results. Overall, this work has fully demonstrated the feasibility of the established ANF platform for screening TIs from Cotinus coggygria Scop., and proved its great prospects for screening bioactive components from natural products.


Subject(s)
Anacardiaceae , Biological Products , Chromatography, Reverse-Phase , Trypsin Inhibitors , Trypsin , Molecular Docking Simulation , Flavonoids/chemistry , Plant Extracts/pharmacology , Anacardiaceae/chemistry
8.
J Chromatogr A ; 1687: 463693, 2023 Jan 04.
Article in English | MEDLINE | ID: mdl-36516530

ABSTRACT

In this study, an advanced at-line nanofractionation based screening platform was developed to screen potential neuraminidase inhibitors (NAIs) from Lonicera japonica Thunb by involving two parallel bioassays, for determining both oseltamivir-sensitive neuraminidase (NAS) and oseltamivir-resistant neuraminidase (NAR) inhibitory activities. 20 potential NAIs with both NAS and NAR inhibitory effects were screened from Lonicera japonica Thunb and identified by mass spectrometer, including 11 phenolic acids, 8 flavonoids and one iridoid glycoside. The proposed at-line nanofractionation based screening platform for NAIs was also used to rapidly screen nine batches of water extracts of Lonicera japonica Thunb or its similar species. Clear differences in the number and content of active components were easily observed, demonstrating that the proposed method possesses great potential for the quality control of herb medicines.


Subject(s)
Influenza A Virus, H1N1 Subtype , Lonicera , Oseltamivir/pharmacology , Neuraminidase , Antiviral Agents/pharmacology , Enzyme Inhibitors/pharmacology , Guanidines/pharmacology
9.
Materials (Basel) ; 15(22)2022 Nov 18.
Article in English | MEDLINE | ID: mdl-36431684

ABSTRACT

Dilution rate is one of most important factors influencing the microstructure and performance of the laser cladding layer. In order to obtain a reasonable dilution rate in the laser cladding layer of Inconel 625 alloy, the laser cladding layers with different Fe content were prepared on the surface of 20# steel by the laser cladding technique. The influence of Fe content on the microstructure and performance of Inconel 625 alloy cladding layer was investigated. The results indicate that with the increase in Fe content in the alloy, the grain size of the cladding layer becomes coarser, the grain orientation difference increases first and then decreases, and the grain boundary angle decreases first and then increases. The hardness, high temperature wear resistance, and high temperature corrosion resistance gradually decreased. It is concluded that the dilution rate of Fe in laser cladding Inconel 625 alloy should be under 5 wt.%.

10.
Molecules ; 27(20)2022 Oct 15.
Article in English | MEDLINE | ID: mdl-36296516

ABSTRACT

How to rapidly and accurately screen bioactive components from complex natural products remains a major challenge. In this study, a screening platform for pancreatic lipase (PL) inhibitors was established by combining magnetic beads-based ligand fishing and high-resolution bioassay profiling. This platform was well validated using a mixture of standard compounds, i.e., (-)- epigallocatechin gallate (EGCG), luteolin and schisandrin. The dose-effect relationship of high-resolution bioassay profiling was demonstrated by the standard mixture with different concentrations for each compound. The screening of PL inhibitors from green tea extract at the concentrations of 0.2, 0.5 and 1.0 mg/mL by independent high-resolution bioassay profiling was performed. After sample pre-treatment by ligand fishing, green tea extract at the concentration of 0.2 mg/mL was specifically enriched and simplified, and consequently screened through the high-resolution bioassay profiling. As a result, three PL inhibitors, i.e., EGCG, (-)-Gallocatechin gallate (GCG) and (-)-Epicatechin gallate (ECG), were rapidly identified from the complex matrix. The established platform proved to be capable of enriching affinity binders and eliminating nonbinders in sample pre-treatment by ligand fishing, which overcame the technical challenges of high-resolution bioassay profiling in the aspects of sensitivity and resolution. Meanwhile, the high-resolution bioassay profiling possesses the ability of direct bioactive assessment, parallel structural analysis and identification after separation. The established platform allowed more accurate and rapid screening of PL inhibitors, which greatly facilitated natural product-based drug screening.


Subject(s)
Catechin , Lipase , Ligands , Luteolin/analysis , Catechin/chemistry , Plant Extracts/chemistry , Biological Assay , Tea/chemistry
11.
Gels ; 8(9)2022 Sep 09.
Article in English | MEDLINE | ID: mdl-36135288

ABSTRACT

Under the background that the in-depth profile control technology is gradually applied in low-permeability fractured reservoirs, this paper regards block H of Changqing Oilfield as the research object, referring to the range of its physical parameters and field application data. Three common in-depth profile control agents (PCAs), nanosphere suspension, poly(ethylene glycol) single-phase gel particle (PEG) and cross-linked bulk gel and swelling particle (CBG-SP), are selected to investigate the compatibility between the fractured channels and the PCAs through a series of experiments. The experimental results show that the nanospheres with particle sizes of 100 nm and 300 nm have good injectivity and deep migration ability, which remains the overall core plugging rate at a high level. The residual resistance coefficient of 800 nm nanospheres decreases in a "cliff" manner along the injection direction due to the formation of blockage in the front section, resulting in a very low plugging rate in the rear section. The injection rate is an important parameter that affects the effect of PEG in the fractured channels. When the injection rate is lower than 0.1 mL/min, the plugging ability will be weakened, and if the injection rate is higher than 0.2 mL/min, the core plugging will occur. The appropriate injection rate will promote the better effect of PEG with the plugging rate > 90%. The average plugging rate of CBG-SP in fractured rock core is about 80%, and the overall control and displacement effect is good. Based on the experimental data of PCAs, the optimization criteria of slug configuration and pro-duction parameters are proposed. According to the principle "blocking, controlling and displacing", references are provided for PCAs screening and parameters selection of field implementation.

12.
Gels ; 8(8)2022 Jul 26.
Article in English | MEDLINE | ID: mdl-35892726

ABSTRACT

Weak gel is a gel system formed by the mixing and crosslinking of a low-concentration polymer and a slow-release crosslinker. It can be used for profile control in deep reservoir, but its effect is greatly affected by mechanical shearing. Currently, the shearing effect on weak gel is mainly studied by way of mechanical stirring, while the effect of porous media shear on weak gel molecules and properties has been rarely discussed. In this paper, polymer solution, aluminum gel and phenolic gel were prepared. The molecular coil size, viscoelastic modulus and microscopic aggregation morphology in water solution of three systems before and after core shearing were investigated, and the injection performance of the three systems in cores with different permeabilities was tested by physical simulation experiments. The study results show that at equivalent permeability, the system with a larger equivalent sphere diameter of molecular coil is more seriously sheared and suffers greater viscosity loss. In the core with permeability of 1.0 D, polymer solution remains as the aggregation, while phenolic gel and aluminum gel cannot form network aggregations and they are inferior to polymer solution in migration capacity in the mid-deep part of the core. In the core with permeability of 1-5.8 D, the polymer solution remains as a Newtonian fluid, while phenolic gel and aluminum gel become purely viscous non-Newtonian fluids. The elastic modulus of aluminum gel and phenolic gel is four times more than that of a polymer. In the core with permeability higher than 8.5 D, aluminum gel and phenolic gel migrate with less effect by core shearing, and their profile control capacity in deep reservoir is higher than that of the polymer. In the core with permeability lower than 8.5 D, because the monomolecular activity of weak gels becomes poor, they migrate in porous media with more effect by core shearing, and their profile control and oil displacement capacity in deep reservoir is lower than that of the polymer.

13.
J Org Chem ; 87(5): 3402-3421, 2022 03 04.
Article in English | MEDLINE | ID: mdl-35171610

ABSTRACT

A photolabile protecting group (PPG) 2-(2-nitrophenyl)-propyloxycarbonyl (NPPOC) was explored in glycosylation and applied in the consecutive synthesis of oligosaccharides. NPPOC displays a strong neighboring group participation (NGP) effect to facilitate the construction of 1,2-trans glycosides in excellent yield. Notably, NPPOC could be efficiently removed by photolysis, and the deprotection conditions are friendly to typical protecting groups. A branched and asymmetric oligomannose Man6 was rapidly prepared, and the consecutive assembly of oligosaccharides without intermediate purification was further investigated owing to the compatibility conditions between NPPPOC's photolysis and glycosylation.


Subject(s)
Glycosides , Oligosaccharides , Glycosylation , Photolysis
14.
Am J Transl Res ; 13(8): 9063-9069, 2021.
Article in English | MEDLINE | ID: mdl-34540019

ABSTRACT

OBJECTIVE: Magnetic resonance imaging (MRI) is increasingly used in the diagnosis of fetal malformations. The purpose of this study was to determine the diagnostic value of 1.5T MRI in fetal head and abdominal malformations. METHODS: A total of 132 pregnant women admitted to Shijiazhuang NO.4 Hospital were included and divided into a control group (CG; n=63) and a research group (RG; n=69) according to different prenatal examination methods. Patients in CG were given ultrasound, while those in RG underwent 1.5T MRI examination. The image quality of 1.5T MRI in different amniotic fluid, different gestational weeks with normal amniotic fluid and different fetal positions with normal amniotic fluid were compared. The detection rate and diagnostic value of the two methods were also compared, with the histological and pathological results as the gold standard. RESULTS: The image quality of 1.5T MRI was not affected by different gestational age with normal amniotic fluid, different fetal positions with normal amniotic fluid, or different amniotic fluid, indicating the feasibility of 1.5T MRI in fetal malformation examination. Histopathological diagnosis revealed 39 cases of head and abdominal deformities in CG and 50 cases in RG. Based on the results of ultrasound examination, there were 32 cases of deformities and 31 of non-deformities in CG. In RG, 1.5T MRI revealed 48 malformations and 21 non-malformations. The sensitivity, specificity, accuracy, missed diagnosis and misdiagnosis rates were 82.05%, 75.00%, 79.37%, 17.95% and 25.00% respectively in CG where ultrasonography was performed, and were 96.00%, 94.74%, 95.65%, 4.00% and 5.26% respectively in RG where 1.5T MRI was performed. The data identified significant differences in sensitivity, accuracy and missed diagnosis between RG and CG. CONCLUSION: 1.5T MRI is effective in diagnosing fetal head and abdominal malformations.

15.
Exp Ther Med ; 22(1): 735, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34055052

ABSTRACT

Oleanolic acid (OA) is a natural compound that can be found in a number of edible and medicinal plants and confers diverse biological actions. However, the direct target of OA in human tumor cells remains poorly understood, preventing its application in clinical and health settings. A previous study revealed that overexpression of caveolin-1 in human leukemia HL-60 cells can increase its sensitivity to OA. The present study aimed to investigate the effects of OA on the doxorubicin-resistant human breast cancer MCF-7 cell line (MCF-7/DOX), harringtonine-resistant human leukemia HL-60 cells (HL-60/HAR) and their corresponding parental cell lines. Western blotting was performed to measure protein expression levels, whilst Cell Counting Kit-8 (CCK-8) assays, cell cycle analysis (by flow cytometry) and apoptosis assays (with Annexin V/PI staining) were used to assess drug sensitivity. CCK-8 assay results suggested that MCF-7/DOX cells, which overexpress the caveolin-1 protein, have similar OA susceptibility to their parent line. In addition, sensitivity of MCF-7/DOX cells to OA was not augmented by knocking down caveolin-1 using RNA interference. HL-60/HAR cells exhibited a four-fold increased sensitivity to OA compared with that in their parental HL-60 cells according to CCK-8 assay. Both of the resistant cell lines exhibited higher numbers of cells at G1 phase arrest compared with those in their parent lines, as measured via flow cytometry. Treatment of both MCF-7 cell lines with 100 µM OA for 48 h induced apoptosis, with increased effects observed in resistant cells. However, no PARP-1 or caspase-3 cleavage was observed, with some positive Annexin V staining found after HL-60/HAR cells were treated with OA, suggesting that cell death occurred via non-classical apoptosis or through other cell death pathways. It was found that OA was not a substrate of ATP-binding cassette subfamily B member 1 (ABCB1) in drug-resistant cells, as indicated by the accumulation of rhodamine 123 assessed using flow cytometry. However, protein expression of ABCB1 in both of the resistant cell lines was significantly decreased after treatment with OA in a concentration-dependent manner. Collectively, these results suggest that OA could reduce ABCB1 protein expression and induce G1 phase arrest in multidrug-resistant cancer cells. These findings highlight the potential of OA for cancer therapy.

16.
J Chromatogr A ; 1647: 462147, 2021 Jun 21.
Article in English | MEDLINE | ID: mdl-33957347

ABSTRACT

Drug-induced phospholipidosis (DIPLD) represents a big concern for both regulatory authorities and pharmaceutical companies in drug discovery. Many researches pointed out that the negatively charged intralysosomal lipids play an important role in the formation of DIPLD. To better mimic this negatively charged lipid surface, a novel immobilized artificial membrane (IAM) column was prepared via in situ copolymerization of 12-methacryloyl n-dodecylphosphocholine (MDPC) and 12-methacryloyl n-dodecylphosphoric acid (MDPA). By introducing MDPA, the surface of the resulting monolithic column can be maintained negatively charged over a broad pH range. Scanning electron microscopy, elemental analysis and nano-HPLC experiments were carried out to characterize the physicochemical properties and chromatographic performance of the obtained monolithic IAM column. The results of ζ-potential and retention mechanism studies indicate that both hydrophobic and electrostatic interactions contribute greatly to the retention of cation analytes owing to the existence of the negatively charged MDPA under acidic conditions. To better assess the DIPLD potency of drug, the molar ratio between MDPC and MDPA in the monolithic column was carefully optimized. The results show that the poly(MDPC70PA30-co-EDMA) column has the best predictability with only two false-positives (donepezil, flecainide) in qualitative analysis of 61 drugs.


Subject(s)
Lysosomal Storage Diseases/chemically induced , Membranes, Artificial , Pharmaceutical Preparations , Phospholipids , Chemistry, Pharmaceutical , Chromatography, High Pressure Liquid , Drug-Related Side Effects and Adverse Reactions/prevention & control , Humans , Hydrophobic and Hydrophilic Interactions , Microscopy, Electron, Scanning , Pharmaceutical Preparations/analysis , Pharmaceutical Preparations/chemistry , Pharmaceutical Preparations/metabolism , Phosphatidic Acids , Phospholipids/chemistry , Phospholipids/metabolism , Static Electricity
17.
Drug Des Devel Ther ; 15: 21-35, 2021.
Article in English | MEDLINE | ID: mdl-33442234

ABSTRACT

OBJECTIVE: Cisplatin (DDP) is an effective first-line therapy for non-small cell lung cancer (NSCLC) treatment; however, it can cause resistance and thus pose an obstacle to the efficacy of chemotherapy in NSCLC. This study aims to detect the effect of RASSF1A on DDP resistance of NSCLC and the underlying mechanism. METHODS: The expression levels of RASSF1A and microtubule-associated protein 1S (MAP1S) were investigated by qRT-PCR and Western blot and their interaction was testified by co-immunoprecipitation (Co-IP) analysis. The IC50 value of DDP on A549 and A549/DDP cells (DDP-resistant cells) was measured. A549/DDP cells were transfected with pCDNA3.1-RASSF1A, pCDNA3.1-MAP1S, or si-RASSF1A, followed by treated with DDP. Cell counting kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EDU) were employed to measure cell survival rate. Western blot was applied to test the levels of autophagy-associated proteins p62, LC3II, and LC3I. Immunofluorescence staining was used to detect the green fluorescent protein (GFP)-LC3 puncta to evaluate the level of autophagy. Finally, a xenograft model in nude mice using A549/DDP cells was developed. RESULTS: RASSF1A and MAP1S were lowly expressed and positively correlated in NSCLC tissues. We observed that RASSF1A and MAP1S overexpression significantly enhanced DDP-induced effects in A549 and A549/DDP cells, including decreased cell viability, as well as increased autophagy levels. Besides, investigations into the mechanism between RASSF1A and MAP1S disclosed that RASSF1A could regulate MAP1S to inactivate the Keap1-Nrf2 pathway, thus activating autophagy to enhance chemosensitivity. Moreover, consistent results were confirmed in vivo experiments. CONCLUSION: RASSF1A increases chemosensitivity in NSCLC by facilitating autophagy via MAP1S-mediated Keap1-Nrf2 pathway.


Subject(s)
Autophagy , Microtubule-Associated Proteins/metabolism , Tumor Suppressor Proteins/metabolism , Humans , Kelch-Like ECH-Associated Protein 1/metabolism , NF-E2-Related Factor 2/metabolism , Tumor Cells, Cultured
18.
J Chromatogr A ; 1635: 461740, 2021 Jan 04.
Article in English | MEDLINE | ID: mdl-33271429

ABSTRACT

In this study, a novel at-line nanofractionation screening platform was successfully developed for the rapid screening and identification of α-glucosidase inhibitors from natural products. A time-course bioassay based on high density well-plates was performed in parallel with high resolution mass spectrometry (MS), providing a straightforward and rapid procedure to simultaneously obtain chemical and biological information of active compounds. Through multiple nanofractionations into the same well-plate and comparisons of the orthogonal separation results of hydrophilic interaction liquid chromatography (HILIC) and reversed-phase liquid chromatography (RPLC), the α-glucosidase inhibitors can be accurately identified from co-eluates. The screening platform was comprehensively evaluated and validated, and was applied to the screenings of green tea polyphenols and Ginkgo folium flavonoids. After accurate peak shape and retention time matching between the bioactivity chromatograms and MS chromatograms, ten α-glucosidase inhibitors were successfully screened out and identified. The proposed screening method is rapid, effective and can avoid ignoring low abundant/active inhibitors.


Subject(s)
Biological Products/chemistry , Chemistry Techniques, Analytical/methods , Glycoside Hydrolase Inhibitors/analysis , Chromatography, Liquid , Chromatography, Reverse-Phase , Flavonoids/chemistry , Flavonoids/isolation & purification , Ginkgo biloba/chemistry , Glycoside Hydrolase Inhibitors/metabolism , Hydrophobic and Hydrophilic Interactions , Mass Spectrometry , Polyphenols/chemistry , Polyphenols/isolation & purification , Tea/chemistry
19.
J Chromatogr A ; 1628: 461481, 2020 Sep 27.
Article in English | MEDLINE | ID: mdl-32822998

ABSTRACT

A single-step copolymerization strategy was developed for the preparation of carbohydrate (glucose and maltose) functionalized monoliths using click reaction. Firstly, novel carbohydrate-functionalized methacrylate monomers were synthesized through Cu(I)-catalyzed 1,3-dipolar cycloaddition (alkyne-azide reaction) of terminal alkyne with azide of carbohydrate derivatives. The corresponding carbohydrate functionalized monolithic columns were then prepared through a single-step in-situ copolymerization. The physicochemical properties and performance of the fabricated monolithic columns were evaluated using scanning electron microscopy, Fourier-transform infrared spectroscopy, and nano-liquid chromatography. For the optimized monolithic column, satisfactory column permeability and good separation performance were demonstrated for polar compounds including nucleoside, phenolic compounds and benzoic acid derivatives. The monolithic column is also highly useful for selective and efficient enrichment of glycopeptides from human IgG tryptic digests. This study not only provided a novel hydrophilic column for separation and selective trapping of polar compounds, but also proposed a facile and efficient approach for preparing carbohydrate functionalized monoliths.


Subject(s)
Carbohydrates/chemistry , Click Chemistry/methods , Carbohydrates/chemical synthesis , Glycopeptides/chemistry , Humans , Hydrophobic and Hydrophilic Interactions , Polymerization , Polymethacrylic Acids/chemical synthesis , Polymethacrylic Acids/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
20.
Cell Cycle ; 19(12): 1502-1516, 2020 06.
Article in English | MEDLINE | ID: mdl-32401659

ABSTRACT

Long non-coding RNAs (lncRNAs) have been proposed as suppressors or promoters in many tumor processes. LncRNA LINC01123 (LINC01123) was a newly identified lncRNA which was firstly functionally analyzed in lung cancer. However, its expression and function in other tumor types were rarely reported. In this study, we firstly confirmed that LINC01123 was highly expressed in both endometrial cancer (EC) tissues and cell lines using bioinformatics analysis and RT-CPR. Then, we preliminarily analyzed the mechanisms involved in overexpression of LINC01123 in EC, finding that STAT1 could bind directly to the LINC01123 promoter region and activate its transcription. Clinical research with 106 patients indicated that high expression of LINC01123 was associated with advanced clinical progression and poor clinical outcome of EC patients. Functionally, knockdown of LINC01123 suppressed the proliferation, migration and invasion of EC cells, and promoted apoptosis. Mechanistically, we observed that LINC01123 may act as an endogenous sponge by competing for miR-516b, thereby regulating KIF4A. Overall, our study revealed a novel LINC01123/miR-516b/KIF4A pathway regulatory axis in EC pathogenesis. LINC01123 may be a novel prognostic biomarker and therapeutic target in EC.Abbreviations: EC: Endometrial cancer; LncRNA: Long non-coding RNA; EMT: epithelial-mesenchymal transition; miRNA: microRNA; qRT-PCR: Quantitative real-time polymerase chain reaction; SPSS: Statistical Package for Social Sciences; Chip: chromatin-immunoprecipitation, TCGA: The Cancer Genome Atlas; CCK-8: Cell Counting Kit-8; KIF4A: Chromosome-associated kinesin KIF4A.


Subject(s)
Disease Progression , Endometrial Neoplasms/genetics , Endometrial Neoplasms/pathology , Kinesins/metabolism , MicroRNAs/metabolism , RNA, Long Noncoding/metabolism , STAT1 Transcription Factor/metabolism , Up-Regulation/genetics , Apoptosis/genetics , Cell Line, Tumor , Cell Proliferation/genetics , Female , Gene Expression Regulation, Neoplastic , Gene Silencing , Humans , Kinesins/genetics , MicroRNAs/genetics , Middle Aged , Multivariate Analysis , Neoplasm Invasiveness , Prognosis , RNA, Long Noncoding/genetics , STAT1 Transcription Factor/genetics
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