Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 278
Filter
Add more filters

Publication year range
1.
EMBO J ; 40(11): e102277, 2021 06 01.
Article in English | MEDLINE | ID: mdl-33876849

ABSTRACT

The ongoing outbreak of severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2) demonstrates the continuous threat of emerging coronaviruses (CoVs) to public health. SARS-CoV-2 and SARS-CoV share an otherwise non-conserved part of non-structural protein 3 (Nsp3), therefore named as "SARS-unique domain" (SUD). We previously found a yeast-2-hybrid screen interaction of the SARS-CoV SUD with human poly(A)-binding protein (PABP)-interacting protein 1 (Paip1), a stimulator of protein translation. Here, we validate SARS-CoV SUD:Paip1 interaction by size-exclusion chromatography, split-yellow fluorescent protein, and co-immunoprecipitation assays, and confirm such interaction also between the corresponding domain of SARS-CoV-2 and Paip1. The three-dimensional structure of the N-terminal domain of SARS-CoV SUD ("macrodomain II", Mac2) in complex with the middle domain of Paip1, determined by X-ray crystallography and small-angle X-ray scattering, provides insights into the structural determinants of the complex formation. In cellulo, SUD enhances synthesis of viral but not host proteins via binding to Paip1 in pBAC-SARS-CoV replicon-transfected cells. We propose a possible mechanism for stimulation of viral translation by the SUD of SARS-CoV and SARS-CoV-2.


Subject(s)
Coronavirus Papain-Like Proteases/metabolism , Gene Expression Regulation, Viral , Peptide Initiation Factors/metabolism , RNA-Binding Proteins/metabolism , RNA-Dependent RNA Polymerase/metabolism , SARS-CoV-2/physiology , Severe acute respiratory syndrome-related coronavirus/physiology , Viral Nonstructural Proteins/metabolism , Amino Acid Sequence , Bacterial Proteins , Chromatography, Gel , Coronavirus Papain-Like Proteases/chemistry , Crystallography, X-Ray , Genes, Reporter , HEK293 Cells , Humans , Immunoprecipitation , Luminescent Proteins , Models, Molecular , Peptide Initiation Factors/chemistry , Protein Binding , Protein Biosynthesis , Protein Conformation , Protein Domains , Protein Interaction Mapping , RNA, Viral/genetics , RNA-Binding Proteins/chemistry , RNA-Dependent RNA Polymerase/chemistry , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/metabolism , Ribosome Subunits/metabolism , Severe acute respiratory syndrome-related coronavirus/genetics , SARS-CoV-2/genetics , Scattering, Small Angle , Sequence Alignment , Sequence Homology, Amino Acid , Viral Nonstructural Proteins/chemistry , X-Ray Diffraction
2.
Org Biomol Chem ; 22(5): 990-997, 2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38180390

ABSTRACT

A thiosuccinimide enabled S-N cross-coupling strategy has been established for the intermolecular N-sulfenylation of clinically approved sulfa drugs under additive-free conditions. This approach features simple operation, high chemoselectivity for sulfenylating the phenylamino group of sulfonamides, wide substrate scope, and easy scale production, affording N-sulfenylated products in moderate to excellent yields (up to 90%). In addition, we also found that this transformation can be realized in a one-pot manner by employing readily available thiols as starting materials, and the obtained sulfonamide derivatives are capable of various late-stage functionalizations, including oxidation, arylation, benzylation, and methylation.

3.
Bioorg Chem ; 143: 107001, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38101266

ABSTRACT

Although the SARS-CoV-2 pandemic has ended, multiple sporadic cases still exist, posing a request for more antivirals. The main protease (Mpro) of SARS-CoV-2, a key enzyme for viral replication, is an attractive target for drug development. Here, we report the discovery of a new potent α-ketoamide-containing Mpro inhibitor, N-((R)-1-cyclohexyl-2-(((R)-3-methoxy-1-oxo-1-((1-(2-oxo-2-((thiazol-2-ylmethyl)amino)acetyl)cyclobutyl)amino)propan-2-yl)amino)-2-oxoethyl)-4,4-difluorocyclohexane-1-carboxamide (20j). This compound presented promising enzymatic inhibitory activity against SARS-CoV-2 Mpro with an IC50 value of 19.0 nM, and an excellent antiviral activity in cell-based assay with an EC50 value of 138.1 nM. This novel covalent inhibitor may be used as a lead compound for subsequent drug discovery against SARS-CoV-2.


Subject(s)
COVID-19 , Coronavirus 3C Proteases , SARS-CoV-2 , Humans , Antiviral Agents/pharmacology , Protease Inhibitors/pharmacology , Molecular Docking Simulation
4.
Ann Surg ; 277(4): 557-564, 2023 04 01.
Article in English | MEDLINE | ID: mdl-36538627

ABSTRACT

OBJECTIVE: To compare neoadjuvant chemotherapy (nCT) with CAPOX alone versus neoadjuvant chemoradiotherapy (nCRT) with capecitabine in locally advanced rectal cancer (LARC) with uninvolved mesorectal fascia (MRF). BACKGROUND DATA: nCRT is associated with higher surgical complications, worse long-term functional outcomes, and questionable survival benefits. Comparatively, nCT alone seems a promising alternative treatment in lower-risk LARC patients with uninvolved MRF. METHODS: Patients between June 2014 and October 2020 with LARC within 12 cm from the anal verge and uninvolved MRF were randomly assigned to nCT group with 4 cycles of CAPOX (Oxaliplatin 130 mg/m2 IV day 1 and Capecitabine 1000 mg/m2 twice daily for 14 d. Repeat every 3 wk) or nCRT group with Capecitabine 825 mg/m² twice daily administered orally and concurrently with radiation therapy (50 Gy/25 fractions) for 5 days per week. The primary end point is local-regional recurrence-free survival. Here we reported the results of secondary end points: histopathologic response, surgical events, and toxicity. RESULTS: Of the 663 initially enrolled patients, 589 received the allocated treatment (nCT, n=300; nCRT, n=289). Pathologic complete response rate was 11.0% (95% CI, 7.8-15.3%) in the nCT arm and 13.8% (95% CI, 10.1-18.5%) in the nCRT arm ( P =0.33). The downstaging (ypStage 0 to 1) rate was 40.8% (95% CI, 35.1-46.7%) in the nCT arm and 45.6% (95% CI, 39.7-51.7%) in the nCRT arm ( P =0.27). nCT was associated with lower perioperative distant metastases rate (0.7% vs. 3.1%, P =0.03) and preventive ileostomy rate (52.2% vs. 63.6%, P =0.008) compared with nCRT. Four patients in the nCT arm received salvage nCRT because of local disease progression after nCT. Two patients in the nCT arm and 5 in the nCRT arm achieved complete clinical response and were treated with a nonsurgical approach. Similar results were observed in subgroup analysis. CONCLUSIONS: nCT achieved similar pCR and downstaging rates with lower incidence of perioperative distant metastasis and preventive ileostomy compared with nCRT. CAPOX could be an effective alternative to neoadjuvant therapy in LARC with uninvolved MRF. Long-term follow-up is needed to confirm these results.


Subject(s)
Neoadjuvant Therapy , Rectal Neoplasms , Humans , Neoadjuvant Therapy/methods , Treatment Outcome , Capecitabine/therapeutic use , Rectal Neoplasms/pathology , Chemoradiotherapy/methods , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasm Staging
5.
Bioorg Med Chem Lett ; 92: 129407, 2023 08 15.
Article in English | MEDLINE | ID: mdl-37437852

ABSTRACT

The COVID-19 pandemic has caused people immense suffering all over the world. Although the World Health Organization (WHO) has announced the end of the pandemic, the sporadic virus epidemic is still ongoing and may exist permanently. Effective antivirals against SARS-CoV-2 are important to deal with the long-term threat. The main protease (Mpro) is a crucial target for drug development due to its role in the process of virus's replication and transcription. Herein, we report benzodiazepine derivatives as a new class of Mpro inhibitors. Structure-activity relationship (SAR) studies led to the discovery of the most active compound, methyl 10-(2-chloroacetyl)-1-oxo-11-(4-(trifluoromethyl)phenyl)-2,3,4,5,10,11-hexahydro-1H-dibenzo[b,e][1,4]-diazepine-7-carboxylate (11a), which shows an IC50 value of 0.180 ± 0.004 µM. The X-ray crystal structure shows that 11a covalently binds to Mpro. Collectively, we have obtained a new small molecule inhibitor targeting Mpro, which can serve as a lead compound for subsequent drug discovery against SARS-CoV-2.


Subject(s)
Benzodiazepines , COVID-19 , Coronavirus 3C Proteases , Protease Inhibitors , Humans , Anticonvulsants , Antiviral Agents/pharmacology , Benzodiazepines/pharmacology , Hypnotics and Sedatives , Molecular Docking Simulation , Pandemics , Protease Inhibitors/chemistry , Protease Inhibitors/pharmacology , SARS-CoV-2/metabolism , Coronavirus 3C Proteases/antagonists & inhibitors
6.
Environ Res ; 217: 114850, 2023 01 15.
Article in English | MEDLINE | ID: mdl-36427640

ABSTRACT

BACKGROUND: Although the existing studies have suggested a significant association between high temperatures and urolithiasis, no nationwide studies have quantified the burden attributable to environmental heat stress and explored how the urolithiasis burden would vary in a warming climate. METHODS: We collected data on urolithiasis attacks from 137 hospitals in 59 main cities from 20 provincial regions of China from 2000 to 2020. An individual-level case-crossover analysis was conducted to estimate the effect of daily wet-bulb globe temperature (WBGT), a heat stress index combining temperature and humidity, on urolithiasis attacks. Stratified analyses were performed by region, age, and sex. We further quantified the future WBGT-related burden of urolithiasis from the Coupled Model Intercomparison Project Phase 6 under three Shared Socioeconomic Pathway (SSP) scenarios. RESULTS: In total, 118,180 urolithiasis patients were evaluated. The exposure-response curve for the association between WBGT and urolithiasis attacks was J-shaped, with a significantly increased risk for WBGT higher than 14.8 °C. The middle-aged and elderly group (≥45 years old) had a higher risk of WBGT-related urolithiasis attacks than in the younger group, while no significant sex difference was observed. The attributable fraction (AF) due to high WBGT would increase from 10.1% in the 2010s to 16.1% in the 2090s under the SSP585 scenario. Warm regions were projected to experience disproportionately higher AFs and larger increments in the future. CONCLUSIONS: This nationwide investigation provides novel evidence on the acute effect of high WBGT on urolithiasis attacks and demonstrates the increasing disease burden in a warming climate.


Subject(s)
Heat Stress Disorders , Occupational Exposure , Middle Aged , Aged , Humans , Male , Female , Climate Change , Hot Temperature , Heat-Shock Response , Heat Stress Disorders/epidemiology , Heat Stress Disorders/etiology , China/epidemiology
7.
Environ Res ; 216(Pt 2): 114596, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36272593

ABSTRACT

Scarce evidence is available on the short-term association between air pollution and type 2 diabetes (T2D). We aimed to evaluate the associations between short-term exposure to six criteria air pollutants and hospitalization for T2D based on a national registry. We conducted an individual-level, time-stratified case-crossover study among inpatients with a primary diagnosis of T2D from 153 hospitals across 20 provincial regions in China (2013-2021). Daily concentrations of fine particulate matter (PM2.5), inhalable particle (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2) and carbon monoxide (CO), and ozone were collected from the nearest monitoring stations. T2D patients were separated into those admission for T2D with and without complications. Distributed lag non-linear models combined with conditional logistic regressions were used to estimate the associations. A total of 88,904 patients were hospitalized for T2D. Short-term exposures to all six air pollutants above except for ozone were significantly associated with the risk of hospitalization for T2D and both subclasses. An interquartile range increase in the concentrations of PM2.5, PM10, NO2, SO2, and CO at lag 0-2 d was associated with higher hospitalization risk of T2D by 1.71% (95%CI: 0.56%, 2.87%), 2.08% (0.88%, 3.29%), 4.85% (3.29%, 6.44%), 2.44% (1.22%, 3.67%) and 2.55% (1.24%, 3.88%), respectively. The associations of T2D hospitalizations were stronger in cold season than in warm season. Air pollutants had more acute and stronger associations with T2D with complications. The exposure-response relationship curves showed no thresholds, and the slopes were larger for T2D with complications. This nationwide individual-level, case-crossover study provides the first comprehensive evidence that short-term exposure to multiple criteria air pollutants may increase the risk of hospitalizations for T2D, especially for T2D with complications.


Subject(s)
Air Pollutants , Air Pollution , Diabetes Mellitus, Type 2 , Ozone , Humans , Nitrogen Dioxide/analysis , Cross-Over Studies , Diabetes Mellitus, Type 2/epidemiology , Air Pollution/adverse effects , Air Pollution/analysis , Air Pollutants/toxicity , Air Pollutants/analysis , Particulate Matter/analysis , Sulfur Dioxide/analysis , Ozone/analysis , Hospitalization , China/epidemiology
8.
Cell Mol Life Sci ; 79(3): 138, 2022 Feb 19.
Article in English | MEDLINE | ID: mdl-35184231

ABSTRACT

Peptidyl-prolyl isomerases (PPIases) catalyze intrinsically slow and often rate-limiting isomerization of prolyl-peptide bonds in unfolded or partially folded proteins, thereby speeding up the folding process and preventing misfolding. They often possess binding and chaperone domains in addition to the domain carrying the isomerization activity. Although generally, their substrates display no identity in their amino acid sequence upstream and downstream of the proline with 20 possibilities for each residue, PPIases are efficient enzymes. SlyD is a highly efficient PPIase consisting of an isomerase domain and an additional chaperone domain. The binding of peptide substrates to SlyD and its enzymatic activity depend to some extend on the proline-proximal residues, however, the impact of proline-distant residues has not been investigated so far. Here, we introduce a label-free NMR-based method to measure SlyD activity on different peptide substrates and analysed the data in the context of obtained binding affinities and several co-crystal structures. We show that especially charged and aromatic residues up to eight positions downstream and three positions upstream of the proline and outside the canonical region of similar conformations affect the activity and binding, although they rarely display distinct conformations in our crystal structures. We hypothesize that these positions primarily influence the association reaction. In the absence of the chaperone domain the isomerase activity strongly correlates with substrate affinity, whereas additional factors play a role in its presence. The mutual orientation of isomerase and chaperone domains depends on the presence of substrates in both binding sites, implying allosteric regulation of enzymatic activity.


Subject(s)
Escherichia coli Proteins/chemistry , Escherichia coli Proteins/metabolism , Escherichia coli/metabolism , Peptide Fragments/metabolism , Peptidylprolyl Isomerase/chemistry , Peptidylprolyl Isomerase/metabolism , Protein Folding , Binding Sites , Catalysis , Escherichia coli/genetics , Peptide Fragments/chemistry , Protein Conformation , Substrate Specificity
9.
J Asian Nat Prod Res ; 25(2): 111-117, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35579284

ABSTRACT

A chemical study of 90% ethanol extract of the barks of Juglans cathayensis resulted in the isolation of three new nortriterpenoids, jugcathenoids A-C (1-3). The structures of the new compounds were elucidated by spectroscopic analysis (NMR, IR, UV, and MS). The isolated nortriterpenoids were tested in vitro for cytotoxic activities against 6 pancreatic cell lines. As a result, compounds 1-3 exhibited some cytotoxic activities against all the tested tumor cell lines with IC50 values less than 50 µM.


Subject(s)
Antineoplastic Agents, Phytogenic , Antineoplastic Agents , Juglans , Juglans/chemistry , Molecular Structure , Cell Line, Tumor , Magnetic Resonance Spectroscopy , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/chemistry
10.
Gynecol Oncol ; 165(3): 538-545, 2022 06.
Article in English | MEDLINE | ID: mdl-35490033

ABSTRACT

OBJECTIVE: To evaluate the value of local treatment in stage IVB cervical cancer (CC). METHODS: Patients diagnosed with stage IVB CC between 2010 and 2015 were included using the data from the Surveillance, Epidemiology, and End Results program. Propensity score matching (PSM) was used to balance the clinicopathological variables of patients. Multivariate Cox regression analyses were performed to analyze the risk factors associated with cause-specific survival (CSS). RESULTS: We identified 960 patients in this study, all patients had received chemotherapy. Of these patients, 818 patients were treated with local treatment (85.2%), including 724 (88.5%) and 94 (11.5%) patients receiving radiotherapy (RT) alone and surgery ± RT, respectively. Local treatment was the independent prognostic factor associated with better CSS. Before PSM, patients who received RT (hazard ratio [HR] 0.633, 95% confidence interval [CI] 0.517-0.775, P < 0.001) or surgery (HR 0.391, 95% CI 0.277-0.552, P < 0.001) were independently associated with a better CSS compared to those with no local treatment. The 3-years CSS rate was 14.4%, 32.4%, and 54.8% in no local treatment, RT alone, and surgery groups, respectively (P < 0.001). Similar results were found after PSM. Patients receiving RT (HR 0.643, 95% CI 0.436-0.947, P = 0.025) and surgery (HR 0.146, 95% CI 0.052-0.410, P < 0.001) had better CSS compared to patients with no local treatment after PSM. While similar CSS was shown between RT alone cohort and the surgery cohort (HR 0.756, 95% CI 0.454-1.260, P = 0.284). CONCLUSIONS: The addition of local surgery or RT to chemotherapy appears to confer improved survival outcomes in patients with stage IVB CC.


Subject(s)
Uterine Cervical Neoplasms , Female , Humans , Neoplasm Staging , Propensity Score , Proportional Hazards Models , SEER Program , Uterine Cervical Neoplasms/pathology
11.
J Chem Inf Model ; 62(4): 945-957, 2022 02 28.
Article in English | MEDLINE | ID: mdl-35128923

ABSTRACT

The NS2B-NS3 protease from Zika virus (ZIKV NS2B-NS3pro) cleaves the viral polyprotein, being essential for its replication and a therapeutic target. Inhibitors that target the active site of ZIKV NS2B-NS3pro have been developed, but they tend to have unfavorable pharmacokinetic properties due to their highly positive charge. Thus, the characterization of allosteric sites in this protease provides new strategies for inhibitor development. Here, we characterized a new allosteric pocket in ZIKV NS2B-NS3pro, analogous to the one previously described for the dengue virus protease. Molecular dynamics simulations indicate the presence of cavities around the residue Ala125, sampling protein conformations in which they are connected to the active site. This link between the residue Ala125 and the active site residues was reinforced by correlation network analysis. To experimentally verify the existence of this allosteric mechanism, we expressed and purified the Ala125Cys mutant of ZIKV NS2B-NS3pro and demonstrated that this variant is inhibited by the thiol-containing chemical probes 5,5'-dithiobis-(2-nitrobenzoic acid) and aldrithiol, which do not affect the activity of the wild-type protein. Inhibition of the mutant protein is reversed by the addition of strong reducing agents, supporting the involvement of Cys125 in covalent bond formation and enzyme inhibition. Together, our results provide experimental evidence for an allosteric pocket in ZIKV NS2B-NS3pro, in the region around Ala125, and computational insights on the structural connection between this region and the enzyme active site.


Subject(s)
Zika Virus , Peptide Hydrolases/metabolism , Protease Inhibitors/pharmacology , Protein Conformation , Serine Endopeptidases , Viral Nonstructural Proteins/chemistry , Viral Proteins
12.
Phys Chem Chem Phys ; 24(33): 19806-19816, 2022 Aug 24.
Article in English | MEDLINE | ID: mdl-35946338

ABSTRACT

Precise regulation of photoexcited charge carriers for separation and transportation is a core requirement for practical application in the photocatalysis field. Herein, a 2D/2D BiOBr/g-C3N4 heterojunction is prepared by a self-assembly method and exhibits enhanced and stable activity for photocatalytic degradation of bisphenol A (BPA) and norfloxacin (NFA) under visible light. Compared to pure g-C3N4, the kinetic constants of BPA and NFA degradation over BiOBr/g-C3N4 are enhanced by about 14.74 and 4.01 times, respectively. The separation and transportation mechanism for the photoexcited charge carriers is clarified by electron paramagnetic resonance (EPR), in situ X-ray photoelectron spectroscopy (in situ XPS), and theoretical calculations. The results show that BiOBr/g-C3N4 exhibits the feature of a relative p-n junction, in which the charges photoexcited on BiOBr/g-C3N4 with high redox potentials can be kept and spatially separated. Moreover, the built-in electric field with the direction of g-C3N4 → BiOBr and the opportune band curvature provide the driving force for charge separation and transportation. Additionally, BPA and NFA degradation intermediates are also detected by liquid chromatography-mass spectrometry. It is of great significance to fabricate efficient photocatalysts for environmental purification and other targeted reactions.


Subject(s)
Bismuth , Norfloxacin , Bismuth/chemistry , Catalysis , Light
13.
Clin Infect Dis ; 73(9): e3261-e3265, 2021 11 02.
Article in English | MEDLINE | ID: mdl-33150367

ABSTRACT

We describe 4 cases of Chlamydia psittaci pneumonia among medical staff in a coronavirus disease 2019 (COVID-19) screening ward, as well as the experience of dealing with this nosocomial infection event. Atypical pneumonia, in addition to COVID-19, should be considered when clustering cases occur, even during a COVID-19 pneumonia pandemic.


Subject(s)
COVID-19 , Chlamydophila psittaci , Pneumonia, Mycoplasma , Chlamydophila psittaci/genetics , Cluster Analysis , Humans , SARS-CoV-2
14.
Opt Lett ; 46(10): 2296-2299, 2021 May 15.
Article in English | MEDLINE | ID: mdl-33988568

ABSTRACT

Planar metalenses provide an effective way to break the diffraction barrier in the far field. Their physical mechanism and applications have been intensively studied in the past decade. These investigations on sub-diffraction-limited light modulations have only been applied to specified single immersion environments; however, changing immersion environments can severely degrade their focusing performance, limiting their application potential. In this work, we propose and experimentally demonstrate an environmentally robust immersion supercritical lens (SCL) that can work in various immersion environments. The design of such a lens is based on the vectorial Rayleigh-Sommerfeld diffraction theory combined with a multi-objective optimization algorithm. The sub-diffraction-limited focusing effect has been experimentally demonstrated in commonly used media, including air, water, and oil, with refractive indices of 1.0, 1.33, and 1.51, respectively. Moreover, such a lens can maintain its effective numerical aperture at a fixed value, bringing a unique advantage in that the lateral size of the focal spots exhibits a similar value of ${{317}}\;{{\pm}}\;{{7}}\;{\rm{nm}}$ in all three media. Our demonstration provides the feasibility of SCLs in various application scenarios with multi-immersion environments, such as bioimaging, light trapping, and optical storage.

15.
Cancer Cell Int ; 21(1): 277, 2021 May 25.
Article in English | MEDLINE | ID: mdl-34034740

ABSTRACT

BACKGROUND: Precise quantification of microRNA is challenging since circulating mRNA and rRNA in the blood are usually degraded. Therefore, it is necessary to identify specific biomarkers for ovarian cancer. This study aimed to investigate candidate circular RNAs (circRNAs) involved in the pathogenic process of ovarian cancer after inhibition of chromodomain helicase DNA binding protein 1-like (CHD1L) and the corresponding mechanism. METHODS: CHD1L mRNA-targeted siRNA was designed and induced a decreased level of CHD1L function in SK-OV-3 and OVCAR-3 cells observed via transwell and wound healing assays and assessment of epithelial-mesenchymal transition (EMT)-related protein expression by immunofluorescence (IF) and western blotting (WB). After decreasing the level of CHD1L, RNA-seq was conducted, and the circRNA expression profiles were obtained. cirRNAs were then selected and validated by PCR together with Sanger sequencing, fluorescent in situ hybridization (FISH), and reverse transcriptase-quantitative PCR (RT-qPCR). Selected circRNA function in vitro was adjusted via interference and overexpression and assessed via transwell assay, tube formation, and EMT-related protein assay by IF and WB; tumor formation in vivo was followed via hematoxylin and eosin (HE) staining and immunohistochemistry of EMT-related proteins. Based on the competing endogenous RNA prediction of circRNA targets, candidate miRNAs were found, and their downstream mRNAs targeted by the selected miRNA were identified and validated by luciferase assay. The functions of these selected miRNA and mRNA were then further investigated through transwell and WB assay of EMT-related proteins. RESULTS: CHD1L was significantly upregulated in ovarian cancer tissues and patients with higher expression of CHD1L had a shorter relapse-free survival (P < 0.001) and overall survival (P < 0.001). Inhibiting the level of CHD1L significantly decreased cell migration and invasion (P < 0.05), increased the expression of epithelial markers, and decreased the expression of mesenchymal markers. Following inhibition of CHD1L expression, RNA-seq was conducted and 82 circRNAs had significantly upregulated expression, while 247 had significantly downregulated expression. The circRNAs were validated by PCR, and hsa_circ_0008305 (circ-PTK2) was selected and further validated by Sanger sequencing, FISH, and RT-qPCR. Circ-PTK2 expression was significantly higher in the ovarian cancer tissues compared with normal ovary tissues (P < 0.001). By regulating the level of circ-PTK2 with siRNA and an overexpression vector, expression of circ-PTK2 was found to be positively correlated to cell migration and invasion. Overexpression of circ-PTK2 enhanced tumor formation and was correlated to expression of EMT pathway markers. Prediction of the target of circ-PTK2 was validated with dual luciferase assay and identified miR-639 and FOXC1 as the valid target of circ-PTK2 and miR-639, respectively. The RNA level of miR-639 was negatively correlated to cell proliferation and migration, whereas the mRNA level of FOXC1 was positively correlated to those processes. miR-639 mimics reversed the function of circ-PTK2 overexpression; however, interference of FOXC1 mRNA also reversed the function of circ-PTK2. CONCLUSIONS: circ-PTK2 is an important molecule in regulating the pathogenic processes of ovarian cancer via the miR-639 and FOXC1 regulatory cascade.

16.
Bioorg Chem ; 108: 104646, 2021 03.
Article in English | MEDLINE | ID: mdl-33484941

ABSTRACT

The transcriptional repressor Snail trriggers epithelial-mesenchymal transition (EMT), the process allowing cancer cells with invasive and metastasis properties. In this study, we screened medicinal plants for the Snail inhibitory active components by high content screen (HCS) and found that the crude extract of Xylopia vielana leaves showed potential activity. Subsequently, bioassay-guided isolation of the extract of Xylopia vielana was performed to obtain twenty-four dimeric guaianes (1-24), including 16 new analogues (1-5, 8-11, 13-15, 17, 18, 21, and 22). Their structures were elucidated by the comprehensive application of multiple spectroscopic methods. Compounds 1, 11, 12, and 16 were initially identified as the active compounds. Wound healing assay, transwell migration assay and western blot experiments verified that compounds 1 and 12 inhibited the expression of Snail in a concentration-dependent manner, and compound 12 was verified as a potent tumor migration inhibitory agent. This work showed a practical strategy for the discovery of new Snail inhibitors from natural products and provided potential insights for dimeric guaianes as anticancer lead compounds specifically targeting Snail protein.


Subject(s)
Plants, Medicinal/chemistry , Sesquiterpenes, Guaiane/pharmacology , Snail Family Transcription Factors/antagonists & inhibitors , Xylopia/chemistry , Dose-Response Relationship, Drug , Humans , Molecular Structure , Plant Leaves/chemistry , Sesquiterpenes, Guaiane/chemistry , Sesquiterpenes, Guaiane/isolation & purification , Structure-Activity Relationship , Tumor Cells, Cultured
17.
Acta Pharmacol Sin ; 42(11): 1798-1807, 2021 11.
Article in English | MEDLINE | ID: mdl-33589794

ABSTRACT

Proliferation of vascular smooth muscle cells (VSMCs) greatly contributes to vascular remodeling in hypertension. This study is to determine the roles and mechanisms of miR-135a-5p intervention in attenuating VSMC proliferation and vascular remodeling in spontaneously hypertensive rats (SHRs). MiR-135a-5p level was raised, while fibronectin type III domain-containing 5 (FNDC5) mRNA and protein expressions were reduced in VSMCs of SHRs compared with those of Wistar-Kyoto rats (WKYs). Enhanced VSMC proliferation in SHRs was inhibited by miR-135a-5p knockdown or miR-135a-5p inhibitor, but exacerbated by miR-135a-5p mimic. VSMCs of SHRs showed reduced myofilaments, increased or even damaged mitochondria, increased and dilated endoplasmic reticulum, which were attenuated by miR-135a-5p inhibitor. Dual-luciferase reporter assay shows that FNDC5 was a target gene of miR-135a-5p. Knockdown or inhibition of miR-135a-5p prevented the FNDC5 downregulation in VSMCs of SHRs, while miR-135a-5p mimic inhibited FNDC5 expressions in VSMCs of both WKYs and SHRs. FNDC5 knockdown had no significant effects on VSMC proliferation of WKYs, but aggravated VSMC proliferation of SHRs. Exogenous FNDC5 or FNDC5 overexpression attenuated VSMC proliferation of SHRs, and prevented miR-135a-5p mimic-induced enhancement of VSMC proliferation of SHR. MiR-135a-5p knockdown in SHRs attenuated hypertension, normalized FNDC5 expressions and inhibited vascular smooth muscle proliferation, and alleviated vascular remodeling. These results indicate that miR-135a-5p promotes while FNDC5 inhibits VSMC proliferation in SHRs. Silencing of miR-135a-5p attenuates VSMC proliferation and vascular remodeling in SHRs via disinhibition of FNDC5 transcription. Either inhibition of miR-135a-5p or upregulation of FNDC5 may be a therapeutically strategy in attenuating vascular remodeling and hypertension.


Subject(s)
Hypertension/metabolism , MicroRNAs/biosynthesis , Muscle, Smooth, Vascular/metabolism , Myocytes, Smooth Muscle/metabolism , Vascular Remodeling/physiology , Animals , Cell Proliferation/physiology , Cells, Cultured , Hypertension/pathology , Male , MicroRNAs/antagonists & inhibitors , Muscle, Smooth, Vascular/ultrastructure , Myocytes, Smooth Muscle/ultrastructure , Rats , Rats, Inbred SHR , Rats, Inbred WKY
18.
Pflugers Arch ; 472(11): 1577-1586, 2020 11.
Article in English | MEDLINE | ID: mdl-32915316

ABSTRACT

Chemical stimulation of kidney causes sympathetic activation and pressor responses in rats. The excitatory renal reflex (ERR) is mediated by angiotensin type 1 receptor (AT1R) and superoxide anions in hypothalamic paraventricular nucleus (PVN). The aim of this study is to determine whether interleukin-1ß (IL-1ß) in the PVN mediates the ERR, and whether the IL-1ß production in the PVN is dependent on the AT1R-superoxide anion signaling. Experiments were performed in adult rats under anesthesia. The ERR was induced by renal infusion of capsaicin, and evaluated by the responses of the contralateral renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP). Inhibition of IL-1ß production with MCC950 in the PVN dose-dependently inhibited the capsaicin-induced ERR and sympathetic activation. The PVN microinjection of IL-1 receptor antagonist IL-1Ra or specific IL-1ß antibody abolished the capsaicin-induced ERR, while IL-1ß enhanced the ERR. Renal infusion of capsaicin promoted p65-NFκB phosphorylation and IL-1ß production in the PVN, which were prevented by PVN microinjection of NADPH oxidase inhibitor apocynin or the superoxide anion scavenger tempol. The PVN microinjection of NFκB inhibitor BMS-345541 abolished the capsaicin induced-ERR and IL-1ß production, but not the NADPH oxidase activation and superoxide anion production. Furthermore, capsaicin-induced p65-NFκB phosphorylation and IL-1ß production in the PVN were prevented by AT1R antagonist losartan, or angiotensin converting enzyme inhibitor captopril. These results indicate that capsaicin-induced ERR and sympathetic activation are mediated by IL-1ß in the PVN. The IL-1ß production in the PVN is dependent on the AT1R-mediated superoxide anion generation and NFκB activation.


Subject(s)
Interleukin-1beta/metabolism , Kidney/physiology , Paraventricular Hypothalamic Nucleus/physiology , Reflex , Acetophenones/pharmacology , Angiotensin II Type 1 Receptor Blockers/pharmacology , Animals , Blood Pressure , Capsaicin/pharmacology , Enzyme Inhibitors/pharmacology , Furans/pharmacology , Imidazoles/pharmacology , Indenes/pharmacology , Kidney/innervation , Losartan/pharmacology , Male , Paraventricular Hypothalamic Nucleus/drug effects , Paraventricular Hypothalamic Nucleus/metabolism , Quinoxalines/pharmacology , Rats , Rats, Sprague-Dawley , Receptor, Angiotensin, Type 1/metabolism , Sulfonamides/pharmacology , Superoxides/metabolism , Sympathetic Nervous System/drug effects , Sympathetic Nervous System/metabolism , Sympathetic Nervous System/physiology , Transcription Factor RelA/antagonists & inhibitors , Transcription Factor RelA/metabolism
19.
Neurobiol Dis ; 146: 105091, 2020 12.
Article in English | MEDLINE | ID: mdl-32979506

ABSTRACT

Enriched environment (EE) with a complex combination of sensorimotor, cognitive and social stimulations has been shown to enhance brain plasticity and improve recovery of functions in animal models of stroke. The present study extended these findings by assessing whether the three-phase EE intervention paradigm would improve neurovascular remodeling following ischemic stroke. Male Sprague-Dawley rats were subjected to permanent middle cerebral artery occlusion (MCAO). A three-phase EE intervention paradigm was designed in terms of the different periods of cerebral ischemia by periodically rearranging the EE cage. Morris water maze (MWM) tests were performed to evaluate the learning and memory function. Multimodal MRI was applied to examine alterations to brain structures, intracranial vessels, and cerebral perfusion on the 31st day after MCAO. The changes of capillaries ultrastructure were examined by transmission electron microscope. Double-immunofluorescent staining was used to evaluate neurogenesis and angiogenesis. The expression of angiogenesis-related factors and neurovascular remodeling related signaling pathways including Phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/glycogen synthase kinase-3 (GSK-3)/ß-catenin and the axon guidance molecules were detected by Western blot analysis. MRI measurements revealed that EE treatment significantly increased survival volume of cortex and striatum, improved cerebral blood flow (CBF), amplified anterior azygos cerebral artery (azACA), ipsilateral internal carotid artery (ICA) and anterior communicating artery (AComA) vessel signal compared with standard housed rats (IS). Consistent with these findings, EE reduced ischemic BBB damage of capillary, enhanced endogenous angiogenesis and modified the expression of VEGF, Ang-1 or Ang-2 in ischemic rats. Additionally, this proangiogenic effect was consistent with the increased progenitor cell proliferation and neuronal differentiation in the peri-infarct cortex and striatum after EE intervention. Specifically, EE intervention paradigm markedly increased expression of phosphorylated PI3K, AKT and GSK-3, but reduced phosphorylated ß-catenin. Moreover, the axon guidance proteins expression level was significant higher in EE group. In parallel to these findings, EE significantly enhanced recovery of lost spatial learning memory function in MCAO rats without affecting infarct size. Together, MRI findings along with histological results strongly supported that the three-phase EE paradigm benefited neurovascular reorganization and thereby improved poststroke cognitive function. Moreover, our findings suggest that this type of EE paradigm induced neurogenesis and angiogenesis, at least in part, via regulating PI3K/AKT/GSK-3/ß-catenin signaling pathway and activation of the intrinsic axonal guidance molecules in animal models of ischemic stroke.


Subject(s)
Brain Ischemia/physiopathology , Brain/physiopathology , Environment , Ischemic Stroke/physiopathology , Recovery of Function/physiology , Animals , Brain/pathology , Cerebrovascular Circulation/physiology , Disease Models, Animal , Infarction, Middle Cerebral Artery/pathology , Male , Neurogenesis/drug effects , Neuronal Plasticity/physiology , Rats, Sprague-Dawley , Stroke/pathology , Stroke/physiopathology
20.
Histochem Cell Biol ; 153(3): 153-164, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31845005

ABSTRACT

The objective of this study is to investigate the expression of enzymes involved in the sulfation of articular cartilage from proximal metacarpophalangeal (PMC) joint cartilage and distal metacarpophalangeal (DMC) joint cartilage in children with Kashin-Beck disease (KBD). The finger cartilage samples of PMC and DMC were collected from KBD and normal children aged 5-14 years old. Hematoxylin and eosin staining as well as immunohistochemical staining were used to observe the morphology and quantitate the expression of carbohydrate sulfotransferase 3 (CHST-3), carbohydrate sulfotransferase 12 (CHST-12), carbohydrate sulfotransferase 13 (CHST-13), uronyl 2-O-sulfotransferase (UST), and aggrecan. In the results, the numbers of chondrocyte decreased in all three zones of PMC and DMC in the KBD group. Less positive staining cells for CHST-3, CHST-12, CHST-13, UST, and aggrecan were observed in almost all three zones of PMC and DMC in KBD. The positive staining cell rates of CHST-12 were higher in superficial and middle zones of PMC and DMC in KBD, and a significantly higher rate of CHST-13 was observed only in superficial zone of PMC in KBD. In conclusion, the abnormal expression of chondroitin sulfate sulfotransferases in chondrocytes of KBD children may provide an explanation for the cartilage damage, and provide therapeutic targets for the treatment.


Subject(s)
Cartilage, Articular/enzymology , Kashin-Beck Disease/enzymology , Sulfotransferases/biosynthesis , Adolescent , Aggrecans/analysis , Aggrecans/biosynthesis , Cartilage, Articular/metabolism , Cartilage, Articular/pathology , Child , Female , Humans , Kashin-Beck Disease/metabolism , Kashin-Beck Disease/pathology , Male , Sulfotransferases/analysis , Carbohydrate Sulfotransferases
SELECTION OF CITATIONS
SEARCH DETAIL