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1.
J Adv Res ; 33: 215-225, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34603791

RESUMO

Introduction: Longxuetongluo Capsule (LTC) is wildly applied to treat ischemic stroke in clinical practice in China. However, the pharmacological mechanism of LTC on ischemic stroke is still unstated. Objective: Our research was designed to study the protective effect of LTC against cerebral ischemia-reperfusion (I/R) injury and reveal the underlying mechanism both in vivo and in vitro. Methods: PC12 cells treated with glucose deprivation/reperfusion (OGD/R) were used to simulate in vitro ischemia/reperfusion (I/R) injury. The cell viability, apoptosis rate, and protein expressions of PC12 cells were evaluated. In vivo validation of the protective effect of LTC was carried out by middle cerebral artery occlusion (MCAO)/reperfusion treatment, and the underlying mechanism of its anti-apoptosis ability was further revealed by immunohistochemistry staining and Western blotting. Results: In the current study, we observed that LTC effectively inhibited oxygen-glucose deprivation/reperfusion (OGD/R) induced apoptosis of PC12 cells through suppressing the cleavage of poly ADP-ribose polymerase (PARP), caspase-3, and caspase-9. Further investigation revealed that OGD/R insult remarkably triggered the endoplasmic reticulum stress responses (ER stress) to induce PC12 cell apoptosis. LTC treatment alleviated OGD/R induced ER stress by inhibiting the activation of protein kinase RNA (PKR)-like ER kinase (PERK)/eukaryotic translation initiation factor 2 (eIF2α) and inositol requiring enzyme 1 (IRE1)/tumor necrosis factor receptor-associated factor 2 (TRAF2) pathways. Additionally, LTC also restrained the OGD/R-induced PC12 cell apoptosis by reversing the activated mitogen-activated protein kinase (MAPK) through IRE1/TRAF2 pathway. Animal studies demonstrated LTC significantly restricted the infarct region induced by middle cerebral artery occlusion (MCAO)/reperfusion, the activation of ER stress and apoptosis of neuronal cells had also been suppressed by LTC in the penumbra region. Conclusion: LTC protects the cerebral neuronal cell against ischemia/reperfusion injury through ER stress and MAPK-mediated mechanisms.

2.
Exp Ther Med ; 22(5): 1200, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34584545

RESUMO

The present study aimed to investigate the regulatory mechanism of chemokine (C-X-C motif) receptor 4 (CXCR4) on endothelial progenitor cells (EPCs) through the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway under hypoxic conditions. Mononuclear cells were isolated from the bone marrow (BM) of young Sprague-Dawley (SD) rats. Bone marrow-derived endothelial progenitor cells (BM-EPCs) were characterized by using Dil-labeled acetylated low-density lipoprotein (Dil-ac-LDL) and fluorescein isothiocyanate-labeled UEA (FITC-UEA-1). Phenotype identification of BM-EPCs was based on red cytoplasm and green cytomembrane. Flow cytometry was employed to examine the markers CD14, CD34, and KDR. Expression level of the EPC-specific surface marker CD14 was found to be negative, while the expression level of CD34 and KDR was positive. In addition, CXCR4 was stably overexpressed in BM-EPCs after transfection with adenovirus-CXCR4. Cell proliferation, migration and apoptosis abilities were measured through the application of CCK-8, followed by Transwell and flow cytometry assays. The expression level of CXCR4, PI3K and Akt was determined by reverse transcription-quantitative PCR and western blotting assays. Functional experiments demonstrated that hypoxia inhibited BM-EPC proliferation and migration, while accelerating BM-EPC apoptosis. Additionally, CXCR4 was found to promote proliferation and migration, and suppress apoptosis in BM-EPCs with or without hypoxia treatment. Evidence also demonstrated that CXCR4 markedly upregulated the expression levels of PI3K and Akt. Furthermore, PI3K inhibitor (LY294002) and CXCR4 inhibitor (AMD3100) effectively inhibited the proliferation, migration and resistance to apoptosis of CXCR4-mediated BM-EPCs under hypoxic conditions.

3.
J Int Med Res ; 49(9): 3000605211040762, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34590923

RESUMO

OBJECTIVE: Previous investigations indicated the anticancer activity of puerarin. The current study aimed to evaluate the effect and molecular mechanisms of puerarin in chemotherapy-resistant ovarian cancer cells. METHODS: We examined the effects of puerarin in platinum-resistant epithelial ovarian cancer cells in vitro and in vivo. We also analyzed the molecular mechanism underlying Wnt/ß-catenin inhibition and sirtuin 1 (SIRT1) regulation following puerarin treatment. RESULTS: Our study demonstrated that puerarin effectively inhibited cell growth in vitro and in vivo by increasing apoptosis in ovarian cancer cells. More importantly, puerarin sensitized cisplatin-resistant ovarian cancer cells to chemotherapy. Puerarin treatment decreased SIRT1 expression, which attenuated the nuclear accumulation of ß-catenin to inhibit Wnt/ß-catenin signaling. In addition, SIRT1 overexpression diminished the effects of puerarin treatment on cisplatin-resistant ovarian cancer cells. Further analysis supported SIRT1/ß-catenin expression as a candidate biomarker for the disease progression of epithelial ovarian cancer. CONCLUSIONS: Puerarin increased the apoptosis of platinum-resistant ovarian cancer cells. The mechanism is partly related to the downregulation of SIRT1 and subsequent inhibition of Wnt/ß-catenin signaling.


Assuntos
Neoplasias Ovarianas , Sirtuína 1 , Apoptose , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/genética , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Isoflavonas , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Sirtuína 1/genética , beta Catenina/genética
4.
Fitoterapia ; 154: 105029, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34506872

RESUMO

Four new chalchonoid trimers, named cochinchinenins N-Q (1-4), along with a pair of known enantiomers (5-6), were isolated from the total phenolic extract of Chinese dragon's blood (the red resin of Dracaena cochinchinensis). The planar structures of 1-4 were elucidated by extensive spectroscopic analysis including HRESIMS and 1D/2D NMR. The absolute configurations of new compounds were established by ECD data. Compound 1 exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated BV-2 microglial cells with IC50 value of 11.5 ± 1.7 µM.


Assuntos
Chalconas/farmacologia , Dracaena/química , Microglia/efeitos dos fármacos , Extratos Vegetais/química , Animais , Linhagem Celular , Chalconas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Camundongos , Óxido Nítrico , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Resinas Vegetais/química
5.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4131-4138, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34467724

RESUMO

Eleven condensed tannins were isolated from the roots of Indigofera stachyodes by various column chromatography techniques including silica gel, octadecyl silica(ODS), Sephadex LH-20, and semi-preparative high performance liquid chromatography(HPLC). These compounds were identified on the basis of physicochemical properties, nuclear magnetic resonance(NMR) and mass spectrometry(MS) data as stachyotannin A(1), epicatechin-(2ß→O→7,4ß→8)-epiafzelechin-(4ß→8)-catechin(2), cinnamtannin D1(3), cinnamtannin B1(4), epicatechin-(2ß→O→7,4ß→8)-epiafzelechin-(4α→8)-epicatechin(5), gambiriin C(6), proanthocyanidin A1(7), proanthocyanidin A2(8), aesculitannin B(9), proanthocyanidin A4(10), and procyanidin B5(11). Compound 1 is a new compound. Compounds 2-11 were isolated from Indigofera for the first time. Furthermore, compounds 1, 2, and 4-11 showed inhibitory effects on thrombin-induced ATP release in platelets.


Assuntos
Indigofera , Proantocianidinas , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Extratos Vegetais
6.
Psychol Health Med ; : 1-6, 2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34402336

RESUMO

To investigate post-traumatic growth induced by COVID-19 pandemic in certain Yunnan residents and to analyze its influencing factors. A total of 581 permanent residents of Yunnan province completed the electronic questionnaire from 18 April 2020 to 26 April 2020. Logistic regression analysis showed that the educational levels, self-perceived health status, family history of infectious diseases, family history of infectious diseases, personality and frequency of going through COVID-19 related news were influencing factors of PTG (P < 0.05). As a traumatic event, the threat of COVID-19 may enable some people to gain positive psychological development in adversity. This will provide reference for public psychological crisis intervention following the COVID-19 pandemic.

7.
Angew Chem Int Ed Engl ; 60(38): 20858-20864, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34309152

RESUMO

In nature, intact apoptotic cells release ATP as a signaling molecule to trigger prompt phagocytic clearance, even at the earliest stage of apoptosis. Inspired by this, here we introduce a straightforward strategy for real-time monitoring ATP exocytosis and drug-stimulated apoptosis in the cancer cell surroundings. Triplex-boosted G-quadruplexes (tb-G4s) responding to cell environmental factors (H+ and K+ ) are engineered to construct a DNA logic-gated nanoplatform for proximity ATP aptasensing on the cell surface. It enables the real-time monitoring of cell apoptosis by capturing released endogenous ATP during chemotherapy drug stimulation, providing a sensitive approach for dynamically evaluating drug-induced apoptosis and therapeutic efficacy.


Assuntos
Trifosfato de Adenosina/metabolismo , Apoptose , Aptâmeros de Nucleotídeos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Quadruplex G/efeitos dos fármacos , Humanos , Fatores de Tempo
8.
Anal Chem ; 93(31): 10834-10840, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34310132

RESUMO

DNAzymes have emerged as an important class of sensors for a wide variety of metal ions, with florescence DNAzyme sensors as the most widely used in different sensing and imaging applications because of their fast response time, high signal intensity, and high sensitivity. However, the requirements of an external excitation light source and its associated power increase the cost and size of the fluorometer, making it difficult to be used for portable detections. To overcome these limitations, we report herein a DNAzyme sensor that relies on chemiluminescence resonance energy transfer (CRET) without the need for external light. The sensor is constructed by combining the functional motifs from both Pb2+-dependent 8-17 DNAzyme conjugated to fluorescein (FAM) and hemin/G-quadruplex that mimics horseradish peroxidase to catalyze the oxidation of luminol by H2O2 to yield chemiluminescence. In the absence of Pb2+, the hybridization between the enzyme and substrate strands bring the FAM and hemin/G-quadruplex in close proximity, resulting in CRET. The presence of Pb2+ ions can drive the cleavage on the substrate strand, resulting in a sharp decrease in the melting temperature of hybridization and thus separation of the FAM from hemin/G-quadruplex. The liberated CRET pair causes a ratiometric increase in the donor's fluorescent signal and a decrease in the acceptor signal. Using this method, Pb2+ ions have been measured rapidly (<15 min) with a low limit of detection at 5 nM. By removing the requirement of exogenous light excitation, we have demonstrated a simple and portable detection using a smartphone, making the DNAzyme-CRET system suitable for field tests of lake water. Since DNAzymes selective for other metal ions or targets, such as bacteria, can be obtained using in vitro selection, the method reported here opens a new avenue for rapid, portable, and ratiometric detection of many targets in environmental monitoring, food safety, and medical diagnostics.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Quadruplex G , DNA Catalítico/metabolismo , Transferência de Energia , Hemina , Peróxido de Hidrogênio , Íons , Luminescência
9.
Bioinorg Chem Appl ; 2021: 7625585, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220997

RESUMO

In order to achieve the controlled release of curcumin, HPMC (hydroxypropyl methyl cellulose) was spray dried with curcumin and lactose. The spray-dried materials were pressed into tablets with a diameter of 8 mm, and their release characteristics in vitro were measured. In vitro experiments showed that the release of curcumin from the HPMC mixture was significantly slower due to the sustained-release property of HPMC as a typical excipient. The release profile of curcumin from the HPMC mixture was relatively stable for a controlled release. SEM images show that the HPMC co-spray-dried powders have crumpled surfaces due to the large molecular weight of HPMC. DSC, XRD, FTIR, N2 adsorption, and TGA have been measured for the spray-dried curcumin materials. This work indicates that HPMC can be used as a controlled-release excipient for curcumin preparations.

10.
Front Mol Biosci ; 8: 666054, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34109213

RESUMO

The novel coronavirus pneumonia COVID-19 is characterized by all age susceptibility, which imposes a dramatic threat to the human species all over the world. According to current available data, the cytokine storm appears to be the most life-threatening symptom of severe COVID-19 cases accompanied with lung fibrosis. Galectin-3 (Gal-3), a member of soluble ß-galactoside-binding lectin families, has been implicated as a key regulator in various inflammation conditions in addition to its well-documented roles in cancer. The pro-inflammatory activity of Gal-3 in the inflammatory response and lung fibrosis of COVID-19 has been proposed by emerging studies, which suggested that inhibition of Gal-3 may represent a novel treatment approach for COVID-19 patients. Intrahepatic cholangiocarcinoma (ICC) is an aggressive malignancy with poor prognosis. ICC accounts for 10-25% of primary liver cancers with limited therapeutic options, which has higher incidence in Asian countries, particularly in China. Cancer patients, including ICC patients, are highly vulnerable to COVID-19 due to their impaired immune system. It is thus undoubtedly a challenge for our oncology department to establish effective treatment strategies under the influence of the COVID-19 crisis. According to our management procedures in the COVID-19 era, emergency treatment will be applied to ICC patients who are under life-threatening conditions, despite the COVID-19 infection. To the best of our knowledge, the modulatory function of Gal-3 in ICC is still barely explored to date. In order to evaluate the therapeutic potential of Gal-3 for ICC patients or those comprised with COVID-19, we herein report our preliminary investigation into roles of Gal-3 in ICC. Our results exhibited that the expression of Gal-3 was significantly up-regulated in ICC tissues, and a significant correlation was observed between its overexpression and malignant progression of ICC cells. We further discussed the activity and possible molecular mechanisms of Gal-3 in ICC, which may pave the ways for further exploring the possibility of Gal-3 as a potential therapeutic target for treating ICC patients or those with COVID-19-related conditions.

11.
Artigo em Inglês | MEDLINE | ID: mdl-34020402

RESUMO

In comparison of liquid chromatography, direct infusion is a superior choice to achieve high-throughput measurements. The specificity and selectivity of tandem mass spectrometry (MS/MS) actually result in a so-called MS separation potential when chemical characterization of herbal medicines. Here, a MS/MSALL program was introduced to promote DI-MS/MS to be an eligible tool for shotgun chemome characterization of Artemisia rupestris L. that is currently drawing worldwide interests because of the promising antiviral activity. After MS1 spectral acquisition for the crude extract, the gas phase fractionation concept enabled the precursor ion cohort sequentially entered the collision cell with a stepped unit mass window (step-size as 1 Da) to generate MS2 spectra, thus generating a unique property integrating the advantages of both data-dependent and data-independent acquisition manners. Even though being free of chromatographic separation, spectrometric separations were accomplished for by MS/MSALL program unless the components shared identical nominal molecular weights. Extensive efforts such as the correlations of MS1 signals with MS2 spectra, structural annotations of fragment ion species, information retrieval in some accessible databases, and referring to the literature data, were devoted for chemical characterization, and as a result, 44 compounds, in total, were structurally identified from 50% aqueous methanol exact of A. rupestris, including 8 caffeoyl quinic acid derivatives, 13 flavonoids, 15 monomeric and dimeric sesquiterpenoids, 4 fatty acids, 2 penylpropanoids, along with 2 other compounds. However, isomers were assigned as an isomeric mixture because their precursor ions always co-existed in a single mass window. Above all, DI-MS/MSALL provides an alternative tool for chemome characterization of herbal medicines, in particular when the great measurement workload for a large sample cohort, attributing to the high-throughput advantage.


Assuntos
Artemisia/química , Plantas Medicinais/química , Espectrometria de Massas em Tandem/métodos , Flavonoides/análise , Flavonoides/química , Isomerismo , Extratos Vegetais/química , Sesquiterpenos/análise , Sesquiterpenos/química
12.
Gigascience ; 10(5)2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33954793

RESUMO

BACKGROUND: Understanding the rate and pattern of germline mutations is of fundamental importance for understanding evolutionary processes. RESULTS: Here we analyzed 19 parent-offspring trios of rhesus macaques (Macaca mulatta) at high sequencing coverage of ∼76× per individual and estimated a mean rate of 0.77 × 10-8de novo mutations per site per generation (95% CI: 0.69 × 10-8 to 0.85 × 10-8). By phasing 50% of the mutations to parental origins, we found that the mutation rate is positively correlated with the paternal age. The paternal lineage contributed a mean of 81% of the de novo mutations, with a trend of an increasing male contribution for older fathers. Approximately 3.5% of de novo mutations were shared between siblings, with no parental bias, suggesting that they arose from early development (postzygotic) stages. Finally, the divergence times between closely related primates calculated on the basis of the yearly mutation rate of rhesus macaque generally reconcile with divergence estimated with molecular clock methods, except for the Cercopithecoidea/Hominoidea molecular divergence dated at 58 Mya using our new estimate of the yearly mutation rate. CONCLUSIONS: When compared to the traditional molecular clock methods, new estimated rates from pedigree samples can provide insights into the evolution of well-studied groups such as primates.


Assuntos
Mutação em Linhagem Germinativa , Taxa de Mutação , Animais , Células Germinativas , Macaca mulatta/genética , Masculino , Filogenia
13.
J Ophthalmol ; 2021: 6620412, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34012681

RESUMO

Purpose: To perform fundus examinations of full-term and premature infants to identify common congenital ocular diseases and determine the incidence and additional risk factors in Ningbo, China. Methods: Fundus examinations were performed on newborns between January 2017 and July 2020 in Ningbo using a RetCam3 or PanoCam LT wide-field digital imaging system. The neonates' birth weight, gestational age, gender, delivery mode, oxygen intake, and other conditions were recorded. We compared the incidence of ocular abnormalities in both full-term newborns and premature infants. Results: There were 23,861 newborns in this study comprising 12,605 (52.8%) male and 11,256 (47.2%) female infants, 20,938 full-term babies, and 2,923 premature babies. The average gestational age was 37.9 ± 5.6 weeks, and the average birth weight was 3,189 ± 417 g. Overall, we found ocular abnormalities in 6,645 (27.8%). The most common abnormality in full-term newborns was retinal hemorrhage (RH), which we found in 3,827 (18.3%) cases. Other diseases identified included familial exudative vitreoretinopathy (FEVR), retinoblastoma (RB), and congenital cataracts. The delivery method had a significant impact on the incidence of neonatal RH (P < 0.001). Retinopathy of prematurity (ROP) was observed in 617 newborns accounting for 21.1% of all screened premature infants. Logistic analysis showed that gestational age and birth weight were important risk factors for ROP (P < 0.001). For treatable diseases, such as ROP, FEVR, congenital cataract, glaucoma, and RB, early identification allows for active treatment or referral to a specialized hospital for further treatment. Conclusion: Early examination and prompt treatment of ocular disorders in newborns are important to avoid lifelong visual impairment. Eye examinations should be performed during the neonatal period and at regular follow-up visits.

14.
Atherosclerosis ; 324: 9-17, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33798923

RESUMO

BACKGROUND AND AIMS: Atherosclerosis progression and regression studies are related to its prevention and treatment. Although we have gained extensive knowledge on germline phospholipid transfer protein (PLTP) deficiency, the effect of inducible PLTP deficiency in atherosclerosis remains unexplored. METHODS: We generated inducible PLTP (iPLTP)-knockout (KO) mice and measured their plasma lipid levels after feeding a normal chow or a Western-type diet. Adenovirus associated virus-proprotein convertase subtilisin/kexin type 9 (AAV-PCSK9) was used to induce hypercholesterolemia in the mice. Collars were placed around the common carotid arteries, and atherosclerosis progression and regression in the carotid arteries and aortic roots were evaluated. RESULTS: On a normal chow diet, iPLTP-KO mice exhibited decreased cholesterol, phospholipid, apoA-I, and apoB levels compared with control mice. Furthermore, the overall amount of high-density lipoprotein (HDL) particles was reduced in these mice, but this effect was more profound for larger HDL particles. On a Western-type diet, iPLTP-KO mice again exhibited reduced levels of all tested lipids, even though the basal lipid levels were increased. Additionally, these mice displayed significantly reduced atherosclerotic plaque sizes with increased plaque stability. Importantly, inducible PLTP deficiency significantly ameliorated atherosclerosis by reducing the size of established plaques and the number of macrophages in the plaques without causing lipid accumulation in the liver. CONCLUSIONS: Induced PLTP deficiency in adult mice reduces plasma total cholesterol and triglycerides, prevents atherosclerosis progression, and promotes atherosclerosis regression. Thus, PLTP inhibition is a promising therapeutic approach for atherosclerosis.


Assuntos
Aterosclerose , Proteínas de Transferência de Fosfolipídeos , Animais , Aterosclerose/genética , Aterosclerose/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Transferência de Fosfolipídeos/genética
15.
Exp Cell Res ; 402(1): 112522, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33771482

RESUMO

Immune escape is the main cause of the low response rate to immunotherapy for cancer, including ovarian cancer. Growth differentiation factor-15 (GDF-15) inhibits immune cell function. However, only few reports described the mechanism. Therefore, the aim of this study was to investigate the mechanism of immune escape regulated by GDF-15 in ovarian cancer. Ovarian cancer patients and healthy women were enrolled in this study. Immunohistochemistry and ELISA were performed to measure GDF-15 expression. Immunoprecipitation combined with mass spectrometry, surface plasmon resonance, and co-immunoprecipitation assay were used to evaluate the interaction between GDF-15 and the surface molecules of DCs. Immunofluorescence analysis, flow cytometry and transwell assay were used to evaluate additional effects of GDF-15 on DCs. The results showed that GDF-15 expression was higher in the ovarian cancer patients compared to that in the healthy women. The TIMER algorithm revealed that highly GDF-15 expression is associated with immune DC infiltration in immunoreactive high-grade serous carcinoma. A further study showed that GDF-15 suppressed DCs maturation, as well as IL-12p40 and TNF-α secretion, the length and number of protrusions and the migration. More importantly, CD44 in the surface of DCs interacted with GDF-15. The overexpression of CD44 in DCs resulted in the suppression of the inhibitory effect of GDF-15 on the length and number of DC synapses. In DCs overexpressing CD44 the inhibition of GDF-15 on the expression of CD11c, CD83 and CD86 was decreased, while in DCs with a knockdown of CD44 the inhibition was further enhanced. Knockdown of CD44 in DCs enhanced the inhibitory effect of GDF-15 on DC migration, while the overexpression of CD44 inhibited the inhibitory effect of GDF-15 on DC migration. In conclusion, the present study suggested that GDF-15 might facilitate ovarian cancer immune escape by interacting with CD44 in DCs to inhibit their function.


Assuntos
Células Dendríticas/imunologia , Fator 15 de Diferenciação de Crescimento/genética , Receptores de Hialuronatos/genética , Neoplasias Ovarianas/genética , Diferenciação Celular/genética , Linhagem Celular Tumoral , Células Dendríticas/patologia , Feminino , Fator 15 de Diferenciação de Crescimento/imunologia , Humanos , Receptores de Hialuronatos/imunologia , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Pessoa de Meia-Idade , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Células Th1/imunologia , Evasão Tumoral/genética , Evasão Tumoral/imunologia
16.
Anal Chem ; 93(13): 5606-5611, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33764756

RESUMO

When dealing with infectious pathogens, the risk of contamination or infection in the process of detecting them is nonnegligible. Separation-free detection will be beneficial in operation and safety. In this work, we proposed a DNAzyme walker for homogeneous and isothermal detection of enterovirus. The DNAzyme is divided into two inactivate subunits. When the subunit-conjugated antibody binds to the target virus, the activity of the DNAzyme recovers as a result of spatial proximity. The walker propels, and the fluorescence recovers. The final fluorescence intensity of the reaction mixture is related to the concentration of the target virus. The detection limit of this proposed method is 6.6 × 104 copies/mL for EV71 and 4.3 × 104 copies/mL for CVB3, respectively. Besides, this method was applied in detection of EV71 in clinical samples with a satisfactory result. The entire experiment is easy to operate, and the proposed method has great potential for practical use.


Assuntos
DNA Catalítico , Enterovirus Humano A , Enterovirus , Antígenos Virais , Fluorescência
17.
J Control Release ; 332: 448-459, 2021 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-33662456

RESUMO

Immunotherapy by stimulating the host immune system has been a promising therapeutic strategy for advanced ovarian cancer. Here we describe a treatment strategy that combines chemotherapy and photo-sonodynamic therapy (PSDT) to induce systemic antitumor immunity. We have successfully fabricated phase-changeable core-shell nanoparticles (OIX_NPs), which carry oxygen in the core and the photosensitizer indocyanine green (ICG)/oxaliplatin (OXP) in the shell for our combination therapy. In the present study, we demonstrated that OIX_NPs have great potential as contrast agents to enhance photoacoustic (PA) imaging. Furthermore, our combined strategy could induce immunogenic cell death (ICD) by promoting surface exposure of calreticulin (CRT) and passive release of high-mobility group box 1 (HMGB1). Importantly, it could inhibit the growth not only primary tumors but also distant tumors in a bilateral syngeneic mouse model by increasing intratumor infiltration of cytotoxic T lymphocytes. In conclusion, the combination of chemotherapy and PSDT has the potential to enhance antitumor immunity significantly and achieve the integration of diagnosis and treatment for ovarian cancer.


Assuntos
Nanopartículas , Neoplasias Ovarianas , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Morte Celular Imunogênica , Camundongos , Neoplasias Ovarianas/tratamento farmacológico , Oxaliplatina , Oxigênio
18.
Artigo em Inglês | MEDLINE | ID: mdl-33545384

RESUMO

Sphingomyelin (SM) is one major phospholipids on lipoproteins. It is enriched on apolipoprotein B-containing particles, including very low-density lipoprotein (VLDL) and its catabolites, low-density lipoprotein (LDL). SM is synthesized by sphingomyelin synthase 1 and 2 (SMS1 and SMS2) which utilizes ceramide and phosphatidylcholine, as two substrates, to produce SM and diacylglyceride. SMS1 and SMS2 activities are co-expressed in all tested tissues, including the liver where VLDL is produced. Thus, neither Sms1 gene knockout (KO) nor Sms2 KO approach is sufficient to evaluate the effect of SMS on VLDL metabolism. We prepared liver-specific Sms1 KO/global Sms2 KO mice to evaluate the effect of hepatocyte SM biosynthesis in lipoprotein metabolism. We found that hepatocyte total SMS depletion significantly reduces cellular sphingomyelin levels. Also, we found that the deficiency induces cellular glycosphingolipid levels which is specifically related with SMS1 but not SMS2 deficiency. To our surprise, hepatocyte total SMS deficiency has marginal effect on hepatocyte ceramide, diacylglyceride, and phosphatidylcholine levels. Importantly, total SMS deficiency decreases plasma triglyceride but not apoB levels and reduces larger VLDL concentration. The reduction of triglyceride levels also was observed when the animals were on a high fat diet. Our results show that hepatocyte total SMS blocking can reduce VLDL-triglyceride production and plasma triglyceride levels. This phenomenon could be related with a reduction of atherogenicity.


Assuntos
Membrana Celular/metabolismo , Hepatócitos/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Lipídeos de Membrana/metabolismo , Transferases (Outros Grupos de Fosfato Substituídos)/deficiência , Animais , Membrana Celular/genética , Lipídeos de Membrana/genética , Camundongos , Camundongos Knockout , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo
19.
ACS Appl Mater Interfaces ; 13(8): 9359-9368, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33169604

RESUMO

Here, fluorescent molecular rotors are employed to develop a new type of high-performance FRET system with large Stokes shift, high photostability, and pH insensitivity, showing great promise for use in proximity-dependent DNA aptasensors. Two carboxylated benzothiazole-based molecular rotors are synthesized, displaying bright green and red fluorescence once labeled to DNA. In the proximity state, an efficient FRET occurs between the two dyes, comparable to that of the most commonly used Cy3/Cy5 pair. Similar phenomena are also observed if naphthothiazole-based analogues are adopted. Our developed FRET pair is then attached to the two parts of a split ATP aptamer in a dimeric DNA nanoscaffold controlled by a bimolecular i-motif. In this way, a pH-switched proximity-induced fluorescent ATP aptasensor is constructed, with good sensitivity, selectivity, and reconfiguration. Furthermore, by altering the linker length of the switching unit, the proximity effect is investigated systematically, providing new insight into DNA proximity reactions and their roles in some physiological processes.


Assuntos
Trifosfato de Adenosina/análise , Aptâmeros de Nucleotídeos/química , Benzotiazóis/química , DNA/química , Corantes Fluorescentes/química , Trifosfato de Adenosina/química , Benzotiazóis/síntese química , Técnicas Biossensoriais/métodos , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/síntese química
20.
Exp Biol Med (Maywood) ; 246(4): 426-435, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33175611

RESUMO

The quorum-sensing (QS) signaling-dependent extracellular virulence factors of Pseudomonas aeruginosa can cause infections such as P. aeruginosa keratitis. P. aeruginosa communicates by secreting and sensing small chemical molecules called autoinducers in QS system. The key QS signal molecule, N-3-oxododecanoyl-homoserine lactone (3OC12HSL), can affect the behavior of host cells and initiate immune response. In this report we investigated the influence of 3OC12HSL on human corneal epithelial cells (HCECs) and the mechanisms of 3OC12HSL on activated toll-like receptor 2 (TLR2)-dependent interleukin-8 (IL-8) secretion in HCECs. Cells were cultured under different concentrations of 3OC12HSL. Cell viability was assessed using Crystal violet staining and the cell counting kit-8 assay. We demonstrated the administration of 3OC12HSL decreased HCEC viability and survival in a concentration- and time-dependent manner. At high concentrations, 3OC12HSL rapidly promoted a time-dependent increase in the expressions of TLR2 and TLR4. It was found that the nuclear translocation and expression of nuclear factor-κB (NF-κB) were also increased in response to 3OC12HSL treatment. The significantly elevated expressions of TLR2, TLR4, and NF-κB, encouraged us to further test their mechanisms that cause inflammatory response. Among the inflammatory factors examined (IL-6, IL-8, IL-10, and TNF-α), we found that IL-8 was significantly increased after treatment with 3OC12HSL and its expression was inhibited when TLR2 was specifically blocked or silenced. These results indicated that the QS signaling molecule 3OC12HSL could be recognized by the host innate immune system in HCECs. This recognition then triggered an immune inflammatory response involving the activation of TLR2 and an increase in expression of IL-8. This crosstalk between 3OC12HSL and host immunity in HCECs contributes to the development and progression of P. aeruginosa keratitis.


Assuntos
4-Butirolactona/análogos & derivados , Células Epiteliais/efeitos dos fármacos , Epitélio Corneano/citologia , Homosserina/análogos & derivados , Pseudomonas aeruginosa/química , 4-Butirolactona/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Células Epiteliais/metabolismo , Homosserina/farmacologia , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-8/metabolismo , NF-kappa B/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo
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