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1.
Cell ; 187(9): 2288-2304.e27, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38565142

RESUMO

Taurine is used to bolster immunity, but its effects on antitumor immunity are unclear. Here, we report that cancer-related taurine consumption causes T cell exhaustion and tumor progression. The taurine transporter SLC6A6 is correlated with aggressiveness and poor outcomes in multiple cancers. SLC6A6-mediated taurine uptake promotes the malignant behaviors of tumor cells but also increases the survival and effector function of CD8+ T cells. Tumor cells outcompete CD8+ T cells for taurine by overexpressing SLC6A6, which induces T cell death and malfunction, thereby fueling tumor progression. Mechanistically, taurine deficiency in CD8+ T cells increases ER stress, promoting ATF4 transcription in a PERK-JAK1-STAT3 signaling-dependent manner. Increased ATF4 transactivates multiple immune checkpoint genes and induces T cell exhaustion. In gastric cancer, we identify a chemotherapy-induced SP1-SLC6A6 regulatory axis. Our findings suggest that tumoral-SLC6A6-mediated taurine deficiency promotes immune evasion and that taurine supplementation reinvigorates exhausted CD8+ T cells and increases the efficacy of cancer therapies.


Assuntos
Linfócitos T CD8-Positivos , Glicoproteínas de Membrana , Taurina , Taurina/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Estresse do Retículo Endoplasmático , Fator 4 Ativador da Transcrição/metabolismo , Transdução de Sinais , Feminino , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Membrana Transportadoras/genética , Fator de Transcrição STAT3/metabolismo
2.
Phytother Res ; 36(9): 3644-3661, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35976195

RESUMO

Neuropathic pain is chronic pain resulting from central or peripheral nerve damage that remains difficult to treat. Current evidence suggests that nobiletin, isolated from Citrus reticulata Blanco, possesses analgesic and neuroprotective effects. However, its effect on neuropathic pain has not been reported. This study evaluated the analgesic effect of nobiletin on neuropathic pain induced by chronic constriction injury (CCI) in mice. In vivo, mice were intragastrically administered with nobiletin (30, 60, 120 mg/kg) for eight consecutive days, respectively. Our study indicated that nobiletin ameliorated mechanical allodynia, cold allodynia and thermal hyperalgesia on CCI mice at doses that do not induce significant sedation. Moreover, nobiletin could ameliorate axonal and myelin injury of the sciatic nerve and further restore abnormal sciatic nerve electrical activity on CCI mice. In vitro studies indicated that nobiletin could suppress the proteins and mRNA expression of the IRF5/P2X4R/BDNF signalling pathway in fibronectin-induced BV2 cells. Overall, our results indicated that nobiletin might exert an analgesic effect on CCI-induced neuropathic pain in mice by inhibiting the IRF5/P2X4R/BDNF signalling pathway in spinal microglia. This study provided a novel potential therapeutic drug for neuropathic pain and new insights into the pharmacological action of nobiletin.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Neuralgia , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Constrição , Modelos Animais de Doenças , Flavonas , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Fatores Reguladores de Interferon/metabolismo , Camundongos , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Nervo Isquiático/lesões
3.
Mikrochim Acta ; 189(1): 43, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34978614

RESUMO

Metal oxide-based macroporous ordered double affinity molecularly imprinted polymers (D-MIPs) were developed as solid phase extraction (SPE) adsorbents for the specific identification of ovalbumin (OVA) under physiological pH conditions prior to ultraviolet visible (UV-vis) spectrophotometric detection. Herein, macroporous alumina (MA) was used as a matrix; dimercaptosuccinic acid (DMSA) and 3-aminophenylboric acid (APBA) were employed as dual-functional monomers; APBA is a self-polymerizing monomer. The effects of synthesis conditions, SPE conditions as well as selectivity, reproducibility, and reusability were studied. The co-modification of DMSA and boronate affinity renders the adsorbent exhibiting a high adsorption capacity (114.4 mg g-1) and short equilibrium time (30 min). The surface imprinting technology causes the adsorbent to have high selectivity towards OVA. The OVA recovery range is 91.1-99.6%. This study provides a promising method for the enrichment of OVA and other cis-diol-containing analytes in complex biological samples. A novel metal oxide-based macroporous ordered nanoparticle with a combination of DMSA and boronate affinity was successfully prepared for specific separation and enrichment of glycoprotein from complex biological samples.


Assuntos
Óxido de Alumínio/química , Boratos/química , Contaminação de Alimentos/análise , Glicoproteínas/análise , Polímeros Molecularmente Impressos/química , Succímero/química , Análise de Alimentos , Tamanho da Partícula , Porosidade , Propriedades de Superfície
4.
Phytother Res ; 35(11): 6389-6400, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34541711

RESUMO

Anti-angiogenic medicines have been evaluated as anticancer therapies, however, their use remains limited in clinical practice due to associated adverse effects. Asiatic acid (AA) is known to have broad-spectrum anticancer properties, however, its effects on angiogenesis in breast cancer remain to be fully established. In this study, we analyzed the inhibitory effects of AA on angiogenesis using human umbilical vein endothelial cells (HUVECs) cultured in vitro and on the growth and metastasis of a subcutaneous breast cancer 4T1 tumor model and a lung metastasis model in vivo. AA significantly inhibited HUVECs proliferation, migration, and tube formation in vitro. In vivo, AA significantly reduced the microvascular density and blood vascular permeability in breast cancer tumors and inhibited growth and lung metastasis. AA inhibited the expression of vascular endothelial growth factor (VEGF) in HUVECs and subsequently downregulated the phosphorylation of vascular endothelial growth factor receptor 2 (VEGFR2) and its downstream target proteins including ERK1/2, Src, and FAK. These results indicate that AA significantly inhibits angiogenesis and blood vessel permeability through the VEGF/VEGFR2 signal axis to inhibit the growth and metastasis of breast cancer. Our data strongly demonstrate the potential applications of AA in the treatment of breast cancer.


Assuntos
Neoplasias da Mama , Fator A de Crescimento do Endotélio Vascular , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Neoplasias da Mama/tratamento farmacológico , Permeabilidade Capilar , Movimento Celular , Proliferação de Células , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Neovascularização Patológica/tratamento farmacológico , Triterpenos Pentacíclicos , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
5.
Int J Integr Care ; 21(3): 7, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539291

RESUMO

BACKGROUND: One of the most noticeable integrated care-related policies in China is the growth and proliferation of County-level Integrated Health Organizations (CIHOs), which take over a set of primary healthcare institutions to form an integrated delivery network in order to achieve an ordered hierarchical delivery system by strengthening primary care. OBJECTIVES: This paper presents emerging findings from an ongoing evaluation of the early impacts of the demonstrator site, Deqing CIHO, in Zhejiang Province, in order to examine the extent to which the implementation has achieved its core objectives: (1) establishing the hierarchical referral system, (2) capacity building of primary healthcare providers, and (3) reducing the costs. DESIGN: This case study was conducted to determine institutional and managerial processes. SETTINGS: Data were collected and analyzed at the CIHO and county level. A structured questionnaire was used for data collection. PRIMARY AND SECONDARY OUTCOME MEASURES: Indicators were selected from the existing database of the county health system and arranged into three segments to assess (1) service utilization among each level of care; (2) capacity-building progress for primary care centers, (3) cost-related indicators for both levels of care. RESULTS: Service utilization data show that one year after CIHO implementation, the proportion of patients who chose to get inpatient care outside of the county decreased from 27.3% to 24.5%. Hospital admissions were retrieved from outside the county, while service volume slightly shifted from hospitals to primary care sites. Capacity-building indicators for township health centers show that 6 out of 12 items showed better performance compared to the national average growth rate, and a moderated growth rate appeared in terms of per capita cost. CONCLUSION: Progress evaluation results from Deqing CIHO indicated some positive effects on three main outcomes, which reveal the potential of CIHOs in not only strengthening primary care but also controlling cost as a result of early implementation. Further emphases of evaluation are required to determine the impacts on the quality and experience of care that are estimated using claim-based data at the individual level.

6.
J Chromatogr A ; 1637: 461829, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33383244

RESUMO

A gallic acid-affinity molecularly imprinted polymer (G-MIP) was first used as an adsorbent for selective identification and capture of luteolin (LTL) in herbal medicine samples. The G-MIP was prepared by using LTL as the template, gallic acid (GA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the crosslinking agent, and 2,2'-azobis(2-methylpropionitrie) (AIBN) as the initiator. The properties of G-MIP were characterized by FT-IR, transmission electron microscope, scanning electron microscope, dynamic light scattering, specific surface area, and X-ray photoelectron spectrum. The adsorption conditions were optimized, and the adsorption equilibrium model and adsorption kinetics model of the adsorbent were investigated under the best experimental conditions. The saturated adsorption capacity is 1.24 mg g-1, which is not only higher than the adsorption capacity of 4-carboxyphenylboronic acid-affinity MIP adsorbent but also superior to those of many reported adsorbents for enriching of LTL. The LTL was quantified by HPLC. The linear range is 0.05-100 mg L-1, the detection limit is 0.020 mg L-1. This method was successfully applied in the selective recognition of LTL in herbal medicines with recoveries of 93.9-114.2%, and the relative standards deviations (RSDs) are 0.4-5.6%. Thus, this work provides a potential possibility and practical platform for the determination of LTL in complex matrices.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácido Gálico/química , Luteolina/análise , Polímeros Molecularmente Impressos/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Chin Med ; 15: 106, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33024448

RESUMO

Neuropathic pain is a debilitating pathological pain condition with a great therapeutic challenge in clinical practice. Currently used analgesics produce deleterious side effects. Therefore, it is necessary to investigate alternative medicines for neuropathic pain. Chinese herbal medicines have been widely used in treating intractable pain. Compelling evidence revealed that the bioactive alkaloids of Chinese herbal medicines stand out in developing novel drugs for neuropathic pain due to multiple targets and satisfactory efficacy. In this review, we summarize the recent progress in the research of analgesic effects of 20 alkaloids components for peripheral neuropathic pain and highlight the potential underlying molecular mechanisms. We also point out the opportunities and challenges of the current studies and shed light on further in-depth pharmacological and toxicological studies of these bioactive alkaloids. In conclusion, the alkaloids hold broad prospects and have the potentials to be novel drugs for treating neuropathic pain. This review provides a theoretical basis for further applying some alkaloids in clinical trials and developing new drugs of neuropathic pain.

8.
Analyst ; 145(6): 2286-2296, 2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32003368

RESUMO

The determination of trace-amount organotins in plastic food packaging materials is of great significance in food safety. However, due to the complexity of organotins and sample treatment processes, it is still a challenging task. Here, we report a method for the sensitive and simultaneous determination of organotins in plastic food packaging materials and edible oils, by utilizing sheathless capillary electrophoresis-electrospray ionization-mass spectrometry. The method of sample pretreatment with ultrasonic extraction and solid phase extraction is used to eliminate interference. The results showed low limits of detection (LODs) of 2 pg mL-1-50 pg mL-1 and excellent inter/intra-day repeatability. Good average recoveries in the range of 80.27% to 108.52% were obtained at three spiked concentrations, with a relative standard deviation less than 8.71%. The successful simultaneous determination of the target analytes will pave the way for further assessment of contamination and migration behaviour of organotins from packaging materials to food, which is of great significance for evaluating and controlling food safety.


Assuntos
Contaminação de Alimentos/análise , Embalagem de Alimentos , Compostos Orgânicos de Estanho/análise , Óleos de Plantas/análise , Plásticos/química , Eletroforese Capilar , Limite de Detecção , Extração em Fase Sólida , Espectrometria de Massas por Ionização por Electrospray
9.
Se Pu ; 37(1): 63-70, 2019 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-30693711

RESUMO

γ-Al2O3 nanoparticle-bonded graphene oxide (γ-Al2O3-GO) was prepared for use as a solid phase extraction absorbent and for preconcentration of four nucleosides in human urine samples for investigation by high-performance liquid chromatography (HPLC). Transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FT-IR) were employed to characterize the absorbent. Several parameters (eluent species, absorbent amount, sample volume, and sample pH) were optimized, and the absorption efficiency was determined based on equilibrium absorbent amounts. Under optimal conditions, the γ-Al2O3-GO absorbent displayed enhanced absorbent ability for nucleosides. The calibration curve showed good linearities in the range of 0.10-10 mg/L for cytidine, inosine, and guanosine, and 0.05-10 mg/L for uridine; the correlation coefficient was observed to be in the range of 0.9967-0.9973. The limits of detection for the four nucleosides were in the range of 0.010-0.021 mg/L. Intra-day and inter-day relative standard deviations were 0.1%-0.8% and 1.0%-3.1%, respectively. The recoveries of the four nucleosides in urine samples ranged from 71.3% to 107.4%, and the relative standard deviations (n=3) were less than 4.8%. The results demonstrated that the proposed method is faster, more sensitive, and more efficient. Therefore, solid phase extraction (SPE)-based γ-Al2O3-GO can be considered more suitable for the determination and enrichment of nucleosides in urine samples.


Assuntos
Óxido de Alumínio , Grafite , Nucleosídeos/urina , Adsorção , Cromatografia Líquida de Alta Pressão , Humanos , Limite de Detecção , Óxidos , Extração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Free Radic Biol Med ; 110: 92-101, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28587909

RESUMO

Flavonoids have been documented to have good antioxidant activities in vitro. However, reports on the cellular antioxidant activities of flavonoid C-glycosides are very limited. In this work, an apigenin C-glycoside was purified from Artocarpus heterophyllus by column chromatography and was identified to be 2″-O-ß-D-xylosylvitexin by nuclear magnetic resonance spectroscopy. The cellular antioxidant activity and anticancer activity of 2″-O-ß-D-xylosylvitexin were evaluated for the first time. The quantitative structure-activity relationship was analysed by molecular modeling. Apigenin presented an unexpected cellular antioxidation behaviour. It had an antioxidant activity at low concentration and a prooxidant activity at high concentration, whereas 2″-O-ß-D-xylosylvitexin showed a dose-dependent cellular antioxidant activity. It indicated that C-glycosidation improved the cellular antioxidation performance of apigenin and eliminated the prooxidant effect. The ortho-dihydroxyl at C-3'/C-4' and C-3 hydroxyl in the flavonoid skeleton play important roles in the antioxidation behaviour. The cell proliferation assay revealed a low cytotoxicity of 2″-O-ß-D-xylosylvitexin.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Artocarpus/química , Flavonoides/isolamento & purificação , Monossacarídeos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Apigenina/química , Apigenina/isolamento & purificação , Apigenina/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromanos/farmacologia , Relação Dose-Resposta a Droga , Flavonoides/química , Flavonoides/farmacologia , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Células Hep G2 , Humanos , Radical Hidroxila/antagonistas & inibidores , Radical Hidroxila/química , Células MCF-7 , Monossacarídeos/química , Monossacarídeos/farmacologia , Picratos/antagonistas & inibidores , Picratos/química , Extratos Vegetais/química , Folhas de Planta/química , Quercetina/química , Quercetina/isolamento & purificação , Quercetina/farmacologia
11.
J Mol Neurosci ; 59(1): 78-89, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26973056

RESUMO

Trigeminal nerve stimulation (TNS) has recently been demonstrated effective in the treatment of epilepsy and mood disorders. Here, we aim to determine the effects of TNS on epileptogenesis, cognitive function, and the associated hippocampal apoptosis and inflammatory responses. Rats were injected with pilocarpine to produce status epilepticus (SE) and the following chronic epilepsy. After SE induction, TNS treatment was conducted for 4 consecutive weeks. A pilocarpine re-injection was then used to induce a seizure in the epileptic rats. The hippocampal neuronal apoptosis induced by seizure was assessed by TUNEL staining and inflammatory responses by immunohistochemistry and enzyme-linked immunosorbent assay (ELISA). The spontaneous recurrent seizure (SRS) number was counted through video monitoring, and the cognitive function assessed through Morris Water Maze (MWM) test. TNS treatment attenuated the SRS attacks and improved the cognitive impairment in epileptic rats. A pilocarpine re-injection resulted in less hippocampal neuronal apoptosis and reduced level of interleukin-1 beta (IL-1ß), tumor necrosis factor-α (TNF-α), and microglial activation in epileptic rats with TNS treatment in comparison to the epileptic rats without TNS treatment. It is concluded that TNS treatment shortly after SE not only protected against the chronic spontaneous seizures but also improved cognitive impairments. These antiepileptic properties of TNS may be related to its attenuating effects on hippocampal apoptosis and pro-inflammatory responses.


Assuntos
Apoptose , Disfunção Cognitiva/terapia , Epilepsia/terapia , Hipocampo/metabolismo , Convulsões/terapia , Estimulação Elétrica Nervosa Transcutânea , Nervo Trigêmeo/fisiologia , Animais , Hipocampo/patologia , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Masculino , Aprendizagem em Labirinto , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
12.
Biomed Chromatogr ; 30(8): 1210-5, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26659432

RESUMO

Natural herbal medicines are an important source of enzyme inhibitors for the discovery of new drugs. A number of natural extracts such as green tea have been used in prevention and treatment of diseases due to their low-cost, low toxicity and good performance. The present study reports an online assay of the activity and inhibition of the green tea extract of the Glucose 6-phosphate dehydrogenase (G6PDH) enzyme using multilayer capillary electrophoresis based immobilized enzyme microreactors (CE-IMERs). The multilayer CE-IMERs were produced with layer-by-layer electrostatic assembly, which can easily enhance the enzyme loading capacity of the microreactor. The activity of the G6PDH enzyme was determined and the enzyme inhibition by the inhibitors from green tea extract was investigated using online assay of the multilayer CE-IMERs. The Michaelis constant (Km ) of the enzyme, the IC50 and Ki values of the inhibitors were achieved and found to agree with those obtained using offline assays. The results show a competitive inhibition of green tea extract on the G6PDH enzyme. The present study provides an efficient and easy-to-operate approach for determining G6PDH enzyme reaction and the inhibition of green tea extract, which may be beneficial in research and the development of natural herbal medicines. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Reatores Biológicos , Eletroforese Capilar/instrumentação , Inibidores Enzimáticos/farmacologia , Glucosefosfato Desidrogenase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Chá/química
13.
Talanta ; 115: 801-5, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24054665

RESUMO

γ-Alumina nanoparticles (γ-Al2O3) were introduced to the conventional poly(methacrylic acid-co-ethylene glycol dimethacrylate) (MAA-co-EGDMA) monolith to prepare a novel organic-inorganic hybrid monolith, poly(MAA-co-EGDMA)-Al2O3 monolith. The polymerization was induced in-situ with UV irradiation in an ultraviolet transparent polymethyl methacrylate (PMMA) microfluidic chip. The monolith-based solid phase microextraction system was used for the on-line determination of 2-amino-4-chlorophenol (ACP) in chlorzoxazone tablets coupled with an optical fiber spectrophotometer. Several parameters affecting the adsorption/desorption, including sample pH value, sample flow rate, sampling time, eluent flow rate, and eluting time, were investigated in detail. Under the optimized conditions, limit of detection (LOD) and limit of quantification (LOQ) of the method were calculated to be 2.8 and 9.1 µg L(-1), respectively, with the relative standard deviation (RSD) of 3.1%.


Assuntos
Clorofenóis/isolamento & purificação , Clorzoxazona/análise , Relaxantes Musculares Centrais/análise , Comprimidos/química , Adsorção , Óxido de Alumínio/química , Contaminação de Medicamentos , Etilenoglicóis/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Metacrilatos/química , Técnicas Analíticas Microfluídicas , Nanopartículas/química , Polimerização , Microextração em Fase Sólida , Raios Ultravioleta
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