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1.
PLoS Genet ; 19(2): e1010640, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36802400

RESUMO

The molecular mechanism of tumor metastasis, especially how metastatic tumor cells colonize in a distant site, remains poorly understood. Here we reported that ARHGAP15, a Rho GTPase activating protein, enhanced gastric cancer (GC) metastatic colonization, which was quite different from its reported role as a tumor suppressor gene in other cancers. It was upregulated in metastatic lymph nodes and significantly associated with a poor prognosis. Ectopic expression of ARHGAP15 promoted metastatic colonization of gastric cancer cells in murine lungs and lymph nodes in vivo or protected cells from oxidative-related death in vitro. However, genetic downregulation of ARHGAP15 had the opposite effect. Mechanistically, ARHGAP15 inactivated RAC1 and then decreased intracellular accumulation of reactive oxygen species (ROS), thus enhancing the antioxidant capacity of colonizing tumor cells under oxidative stress. This phenotype could be phenocopied by inhibition of RAC1 or rescued by the introduction of constitutively active RAC1 into cells. Taken together, these findings suggested a novel role of ARHGAP15 in promoting gastric cancer metastasis by quenching ROS through inhibiting RAC1 and its potential value for prognosis estimation and targeted therapy.


Assuntos
Neoplasias Gástricas , Camundongos , Animais , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Gástricas/genética , Regulação para Baixo , Estresse Oxidativo , Proteínas rac1 de Ligação ao GTP/genética , Linhagem Celular Tumoral
2.
J Neurosci ; 43(4): 526-539, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36283831

RESUMO

The transmembrane protein TMEM206 was recently identified as the molecular basis of the extracellular proton-activated Cl- channel (PAC), which plays an essential role in neuronal death in ischemia-reperfusion. The PAC channel is activated by extracellular acid, but the proton-sensitive mechanism remains unclear, although different acid-sensitive pockets have been suggested based on the cryo-EM structure of the human PAC (hPAC) channel. In the present study, we firstly identified two acidic amino acid residues that removed the pH-dependent activation of the hPAC channel by neutralization all the conservative negative charged residues located in the extracellular domain of the hPAC channel and some positively charged residues at the hotspot combined with two-electrode voltage-clamp (TEVC) recording in the Xenopus oocytes system. Double-mutant cycle analysis and double cysteine mutant of these two residues proved that these two residues cooperatively form a proton-sensitive site. In addition, we found that chloral hydrate activates the hPAC channel depending on the normal pH sensitivity of the hPAC channel. Furthermore, the PAC channel knock-out (KO) male mice (C57BL/6J) resist chloral hydrate-induced sedation and hypnosis. Our study provides a molecular basis for understanding the proton-dependent activation mechanism of the hPAC channel and a novel drug target of chloral hydrate.SIGNIFICANCE STATEMENT Proton-activated Cl- channel (PAC) channels are widely distributed in the nervous system and play a vital pathophysiological role in ischemia and endosomal acidification. The main discovery of this paper is that we identified the proton activation mechanism of the human proton-activated chloride channel (hPAC). Intriguingly, we also found that anesthetic chloral hydrate can activate the hPAC channel in a pH-dependent manner. We found that the chloral hydrate activates the hPAC channel and needs the integrity of the pH-sensitive site. In addition, the PAC channel knock-out (KO) mice are resistant to chloral hydrate-induced anesthesia. The study on PAC channels' pH activation mechanism enables us to better understand PAC's biophysical mechanism and provides a novel target of chloral hydrate.


Assuntos
Hidrato de Cloral , Canais de Cloreto , Camundongos , Animais , Masculino , Humanos , Hidrato de Cloral/farmacologia , Canais de Cloreto/genética , Canais de Cloreto/metabolismo , Prótons , Cloretos/metabolismo , Camundongos Endogâmicos C57BL
3.
J Neurosci ; 43(15): 2665-2681, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36898835

RESUMO

The Slack channel (KCNT1, Slo2.2) is a sodium-activated and chloride-activated potassium channel that regulates heart rate and maintains the normal excitability of the nervous system. Despite intense interest in the sodium gating mechanism, a comprehensive investigation to identify the sodium-sensitive and chloride-sensitive sites has been missing. In the present study, we identified two potential sodium-binding sites in the C-terminal domain of the rat Slack channel by conducting electrophysical recordings and systematic mutagenesis of cytosolic acidic residues in the rat Slack channel C terminus. In particular, by taking advantage of the M335A mutant, which results in the opening of the Slack channel in the absence of cytosolic sodium, we found that among the 92 screened negatively charged amino acids, E373 mutants could completely remove sodium sensitivity of the Slack channel. In contrast, several other mutants showed dramatic decreases in sodium sensitivity but did not abolish it altogether. Furthermore, molecular dynamics (MD) simulations performed at the hundreds of nanoseconds timescale revealed one or two sodium ions at the E373 position or an acidic pocket composed of several negatively charged residues. Moreover, the MD simulations predicted possible chloride interaction sites. By screening predicted positively charged residues, we identified R379 as a chloride interaction site. Thus, we conclude that the E373 site and the D863/E865 pocket are two potential sodium-sensitive sites, while R379 is a chloride interaction site in the Slack channel.SIGNIFICANCE STATEMENT The research presented here identified two distinct sodium and one chloride interaction sites located in the intracellular C-terminal domain of the Slack (Slo2.2, KCNT1) channel. Identification of the sites responsible for the sodium and chloride activation of the Slack channel sets its gating property apart from other potassium channels in the BK channel family. This finding sets the stage for future functional and pharmacological studies of this channel.


Assuntos
Canais de Potássio Ativados por Sódio , Animais , Ratos , Cloretos/metabolismo , Canais de Potássio Ativados por Sódio/metabolismo , Sódio/metabolismo
4.
Langmuir ; 38(9): 2993-2999, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35212548

RESUMO

Metallic materials with unique surface structure have attracted much attention due to their unique physical and chemical properties. However, it is hard to prepare bulk metallic materials with special crystal faces, especially at the nanoscale. Herein, we report an efficient method to adjust the surface structure of a Cu plate which combines ion implantation technology with the oxidation-etching process. The large number of vacancies generated by ion implantation induced the electrochemical oxidation of several atomic layers in depth; after chemical etching, the Cu(100) planes were exposed on the surface of the Cu plate. As a catalyst for acid hydrogen evolution reaction, the Cu plate with (100) planes merely needs 273 mV to deliver a current density of 10 mA/cm2 because the high-energy (100) surface has moderate hydrogen adsorption and desorption capability. This work provides an appealing strategy to engineer the surface structure of bulk metallic materials and improve their catalytic properties.

5.
Australas J Dermatol ; 63(2): 217-221, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35229882

RESUMO

OBJECTIVES: The study evaluated the efficacy of thalidomide in prevention of camrelizumab-induced reactive cutaneous capillary endothelial proliferation (RCCEP). METHODS: In this study, patients treated with camrelizumab plus thalidomide or camrelizumab alone were included. The occurrences, onset time, severity of RCCEP and the adverse effect of thalidomide were analysed. RESULTS: A total of 19 patients were enrolled. The incidence of RCCEP in thalidomide group (2/9, 22.2%) was significantly lower than that in camrelizumab group (8/10, 80%). The median onset time of RCCEP was 5 weeks and 4 weeks respectively. The adverse events of thalidomide were mild, and no treatment-associated interruption was observed. CONCLUSIONS: Thalidomide showed a promising in prevention of the RCCEP in patients receiving camrelizumab therapy with an acceptable safety profile.


Assuntos
Anticorpos Monoclonais Humanizados , Talidomida , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Proliferação de Células , Humanos , Talidomida/efeitos adversos
6.
Zhonghua Nan Ke Xue ; 27(4): 314-318, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-34914213

RESUMO

OBJECTIVE: To investigate the effect of modified Vattikuti Institute prostatectomy (mVIP) in the treatment of localized PCa. METHODS: This retrospective study included 50 cases of localized PCa treated by mVIP and another 50 by robot-assisted radical prostatectomy (RARP) from March 2018 to April 2019. We analyzed the baseline data, the surgical techniques used and the results of short-term follow-up. RESULTS: All the operations were completed successfully without conversion to open surgery. The mVIP group, compared with the RARP, showed longer operation time (ï¼»90.35 ± 24.22ï¼½ vs ï¼»84.46 ± 19.18ï¼½ min, P > 0.05), more intraoperative blood loss (ï¼»220.00 ± 15.10ï¼½ vs ï¼»215.00 ± 15.10ï¼½ ml, P > 0.05), shorter postoperative hospital stay (ï¼»5.75 ± 1.45ï¼½ vs ï¼»6.20 ± 1.50ï¼½ d, P > 0.05), and higher rates of positive surgical margins (22.00% vs 14.00%, P > 0.05) and urinary continence at 1 month (76%vs 22%,P < 0.05), 6 months (84% vs 79%, P > 0.05) and 12 months after surgery (96% vs 94%, P > 0.05). CONCLUSIONS: Modified VIP can better preserve the lateral and posterolateral prostatic fascial tissue in the treatment of localized PCa and therefore significantly promote the recovery of urinary continence after surgery.


Assuntos
Prostatectomia , Neoplasias da Próstata , Humanos , Masculino , Duração da Cirurgia , Próstata/cirurgia , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos
7.
J Biol Chem ; 294(31): 11892-11909, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31201274

RESUMO

The cardiac mechanosensitive BK (Slo1) channels are gated by Ca2+, voltage, and membrane stretch. The neuropeptide GsMTx4 is a selective inhibitor of mechanosensitive (MS) channels. It has been reported to suppress stretch-induced cardiac fibrillation in the heart, but the mechanism underlying the specificity and even the targeting channel(s) in the heart remain elusive. Here, we report that GsMTx4 inhibits a stretch-activated BK channel (SAKcaC) in the heart through a modulation specific to mechano-gating. We show that membrane stretching increases while GsMTx4 decreases the open probability (Po) of SAKcaC. These effects were mostly abolished by the deletion of the STREX axis-regulated (STREX) exon located between RCK1 and RCK2 domains in BK channels. Single-channel kinetics analysis revealed that membrane stretch activates SAKcaC by prolonging the open-time duration (τO) and shortening the closed-time constant (τC). In contrast, GsMTx4 reversed the effects of membrane stretch, suggesting that GsMTx4 inhibits SAKcaC activity by interfering with mechano-gating of the channel. Moreover, GsMTx4 exerted stronger efficacy on SAKcaC under membrane-hyperpolarized/resting conditions. Molecular dynamics simulation study revealed that GsMTx4 appeared to have the ability to penetrate deeply within the bilayer, thus generating strong membrane deformation under the hyperpolarizing/resting conditions. Immunostaining results indicate that BK variants containing STREX are also expressed in mouse ventricular cardiomyocytes. Our results provide common mechanisms of peptide actions on MS channels and may give clues to therapeutic suppression of cardiac arrhythmias caused by excitatory currents through MS channels under hyper-mechanical stress in the heart.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Venenos de Aranha/metabolismo , Animais , Membrana Celular/metabolismo , Galinhas , Embrião não Mamífero/metabolismo , Cinética , Canais de Potássio Ativados por Cálcio de Condutância Alta/antagonistas & inibidores , Canais de Potássio Ativados por Cálcio de Condutância Alta/genética , Camundongos , Simulação de Dinâmica Molecular , Miócitos Cardíacos/classificação , Miócitos Cardíacos/metabolismo , Técnicas de Patch-Clamp , Domínios Proteicos
8.
Am J Nephrol ; 51(8): 624-634, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32694247

RESUMO

AIM: To investigate the relationship between hemoglobin levels and the progression of IgA nephropathy (IgAN). METHODS: In a two-center cohort of 1,828 cases with biopsy-proven IgAN, we examined the association of hemoglobin levels with the primary outcome of a composite of all-cause mortality or kidney failure defined as a 40% decline in eGFR, or ESKD (defined as eGFR <15 mL/min/1.73 m2 or need for kidney replacement therapy including hemodialysis, peritoneal dialysis, or kidney transplantation), or the outcome of kidney failure, assessed using Cox and logistic regression models, respectively, with adjustment for confounders. RESULTS: At baseline, mean age, eGFR, and hemoglobin levels were 33.75 ± 11.03 years, 99.70 ± 30.40 mL/min/1.73 m2, and 123.47 ± 18.36 g/L, respectively. During a median of approximately 7-year follow-up, 183 cases reached the composite outcome. After adjustment for demographic and IgAN-specific covariates and treatments, a lower quartile of hemoglobin was nonlinearly associated with an increased risk of the primary outcome or kidney failure in the Cox proportional hazards models (primary outcome: HR for quartile 3 vs. 4, 1.37; 95% CI, 0.83-2.25; HR for quartile 2 vs. 4, 1.18; 95% CI, 0.68-2.07; HR for quartile 1 vs. 4, 1.91; 95% CI, 1.15-3.17; kidney failure: HR for quartile 3 vs. 4, 1.39; 95% CI, 0.84-2.31; HR for quartile 2 vs. 4, 1.20; 95% CI, 0.68-2.11; HR for quartile 1 vs. 4, 1.83; 95% CI, 1.09-3.07) in the fully adjusted model. Then, hemoglobin levels were transformed to a binary variable for fitting the model according to the criteria for anemia of 110 g/L in the women and 120 g/L in men in China. The participants in the anemia group had an increased risk of developing outcomes compared with the nonanemia group in both genders (primary outcome: male: HR, 1.64; 95% CI, 1.01-2.68; female: HR, 1.68; 95% CI, 1.02-2.76; kidney failure: male: HR, 1.60; 95% CI, 0.97-2.64; female: HR, 1.58; 95% CI, 0.95-2.61) in the fully adjusted model. CONCLUSIONS: A low level of hemoglobin was nonlinearly associated with IgAN progression. The anemic IgAN patients presented a higher risk of developing poor outcomes compared with the nonanemic patients.


Assuntos
Anemia/diagnóstico , Glomerulonefrite por IGA/patologia , Hemoglobinas/análise , Falência Renal Crônica/epidemiologia , Adulto , Anemia/sangue , Anemia/epidemiologia , Anemia/etiologia , Biópsia , China/epidemiologia , Progressão da Doença , Feminino , Seguimentos , Taxa de Filtração Glomerular , Mesângio Glomerular/patologia , Glomerulonefrite por IGA/sangue , Glomerulonefrite por IGA/complicações , Glomerulonefrite por IGA/diagnóstico , Humanos , Falência Renal Crônica/patologia , Falência Renal Crônica/terapia , Transplante de Rim/estatística & dados numéricos , Masculino , Diálise Renal/estatística & dados numéricos , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Adulto Jovem
9.
Zhongguo Zhong Yao Za Zhi ; 44(5): 905-911, 2019 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-30989848

RESUMO

Ganoderic acid(GA) is one of main bioactive components produced by Ganoderma lucidum,which a traditional Chinese herbal medicine and a kind of tracyclic triterpene lanosterol derivatives with highly oxidized structure. It has a variety of important pharmacological activities,such as anticancer,immunoregulation,anti-oxidation,anti-diabetes and anti-HIV. At present,the studies of GA mainly focus on biosynthesis,fermentation control,isolation and purification,structure identification and pharmacological effects.However,there are a fewer pharmacokinetic studies of GA,although it is closely related to the clinical application. Recent studies have shown that GA can be absorbed rapidly by gastrointestinal tract and distributed in various tissues and organs after oral intake. GA is metabolized by liver at phase Ⅰ and phase Ⅱ,and then mainly excreted by bile. In this paper,the pharmacokinetic characteristics of GA and its absorption,distribution,metabolism and excretion(ADME) will be systematically summarized,in order to provide scientific basis for the application and development studies of Ganoderma triterpenoid drugs and their rational clinical use.


Assuntos
Reishi/química , Triterpenos/farmacocinética , Humanos , Lanosterol/farmacocinética
10.
J Biol Chem ; 292(28): 11740-11750, 2017 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-28572510

RESUMO

Polycystic ovary syndrome is a common endocrine disorder and a major cause of anovulatory sterility in women at reproductive age. Most patients with polycystic ovary syndrome have hyperandrogenism, caused by excess androgen synthesis. Bone morphogenetic protein 4 (BMP4) is an essential regulator of embryonic development and organ formation, and recent studies have also shown that BMP4 may be involved in female steroidogenesis process. However, the effect of BMP4 on hyperandrogenism remains unknown. Here, using a female mouse model of hyperandrogenism, we found that ovarian BMP4 levels were significantly decreased in hyperandrogenism. Elevated androgens inhibited BMP4 expression via activation of androgen receptors. Moreover, BMP4 treatment suppressed androgen synthesis in theca cells and promoted estrogen production in granulosa cells by regulating the expression of steroidogenic enzymes, including CYP11A, HSD3B2, CYP17A1, and CYP19A1 Consistently, knockdown of BMP4 augmented androgen levels and inhibited estrogen levels. Mechanistically, Smad signaling rather than the p38 MAPK pathway regulated androgen and estrogen formation, thereby mediating the effect of BMP4. Of note, BMP4-transgenic mice were protected against hyperandrogenism. Our observations clarify a vital role of BMP4 in controlling sex hormone levels and offer new insights into intervention for managing hyperandrogenism by targeting the BMP4-Smad signaling pathway.


Assuntos
Proteína Morfogenética Óssea 4/metabolismo , Modelos Animais de Doenças , Hiperandrogenismo/etiologia , Ovário/metabolismo , Síndrome do Ovário Policístico/fisiopatologia , Transdução de Sinais , Proteína Smad4/metabolismo , Androgênios/metabolismo , Androgênios/farmacologia , Animais , Proteína Morfogenética Óssea 4/antagonistas & inibidores , Proteína Morfogenética Óssea 4/genética , Células Cultivadas , Desidroepiandrosterona , Regulação para Baixo/efeitos dos fármacos , Estrogênios/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Células da Granulosa/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ovário/efeitos dos fármacos , Ovário/patologia , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Interferência de RNA , Receptores Androgênicos/química , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Smad4/antagonistas & inibidores , Proteína Smad4/genética , Células Tecais/efeitos dos fármacos , Células Tecais/metabolismo , Células Tecais/patologia
11.
Ecotoxicology ; 27(3): 325-335, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29404866

RESUMO

Phenylalanine ammonia-lyase (PAL) is one of the principle enzymes involved in plant's secondary metabolism. Expression of individual isogene from the PAL gene family is variable with species of plants in responses to different stresses. In this study, transcriptome analysis of the PAL gene family in rice seedlings exposed to potassium chromate Cr(VI) or chromium nitrate Cr(III) was conducted using Agilent 44K rice microarray and real-time quantitative RT-PCR. Uptake and accumulation of both Cr species by rice seedlings and their effect on PAL activity were also determined. Three days of Cr exposure led to significant accumulation of Cr in plant tissues, but majority being in roots rather than shoots. Changes of PAL activities in rice tissues were evident from both Cr treatments. Individual isogene from the rice PAL gene family was expressed differentially in response to both Cr variants. Comparing gene expression between two Cr treatments, only osPAL2 and osPAL4 genes were expressed in similar patterns. Also, gene expression pattern was inconsistent in both plant tissues. Results indicated that expression of individual isoform from the rice PAL gene family is tissue, and stimulus specific under different Cr exposure, suggesting their different detoxification strategies for decreasing or eliminating Cr stresses.


Assuntos
Cromatos/efeitos adversos , Compostos de Cromo/efeitos adversos , Regulação da Expressão Gênica de Plantas , Nitratos/efeitos adversos , Oryza/genética , Fenilalanina Amônia-Liase/genética , Proteínas de Plantas/genética , Compostos de Potássio/efeitos adversos , Poluentes do Solo/efeitos adversos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Isoenzimas , Análise de Sequência com Séries de Oligonucleotídeos , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Fenilalanina Amônia-Liase/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Reação em Cadeia da Polimerase , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
12.
Hell J Nucl Med ; 21(1): 48-54, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29550846

RESUMO

OBJECTIVE: To evaluate whether computed tomography attention correction (CTAC) has incremental diagnostic value for single photon emission tomography (SPET) myocardial perfusion imaging (MPI) for the detection of coronary artery disease (CAD) in Chinese patients. SUBJECTS AND METHODS: This retrospective study consisted of 181 suspected CAD patients who underwent one-stop SPET examination by MPI combined with a CT scan. Two observers independently evaluated non-attenuation correction (NAC) and CTAC MPI images, and coronary angiography (CAG) results were used as reference standards. The diagnostic efficacies of the two methods were compared. RESULTS: a) In the whole group, the sensitivity, specificity and accuracy for the detection of CAD were found to be 75.7%, 55.1% and 63.5% for NAC images and 52.7%, 86.9% and 72.9% for CTAC images, respectively; the areas under the receiver operating characteristic curves (AUC) were 0.654 and 0.698 (P>0.05). b) The accuracy of CTAC and the AUC were significantly higher than those for NAC in Chinese males. c) The accuracy of CTAC was also significantly increased for the right coronary artery (RCA) territory and in overweight patients (BMI≥24), although differences in the AUC were marginally insignificant. CONCLUSION: Compared to NAC MPI, CTAC improved SPET MPI specificity but decreased sensitivity, leading to no obvious improvement in overall accuracy for the diagnosis of CAD in Chinese patients. However, CTAC might be of value in the subgroups of males and overweight patients and for the RCA territory. In routine clinical application, the integration of NAC and CTAC findings combined with CAD pre-test probability could improve MPI diagnostic performance.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Área Sob a Curva , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
13.
EMBO Rep ; 16(11): 1563-80, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26415504

RESUMO

Apoptosis-inducing factor (AIF) exerts dual roles on cell death and survival, but its substrates as a putative oxidoreductase and roles in tumorigenesis remain elusive. Here, we report that AIF physically interacts with and inhibits the oxidation of phosphatase and tensin homolog on chromosome ten (PTEN), a tumor suppressor susceptible for oxidation-mediated inactivation. More intriguingly, we also identify PTEN as a mitochondrial protein and the ectopic expression of mitochondrial targeting sequence-carrying PTEN almost completely inhibits Akt phosphorylation in PTEN-deficient cells. AIF knockdown causes oxidation-mediated inactivation of the lipid phosphatase activity of PTEN, with ensuing activation of Akt kinase, phosphorylation of the Akt substrate GSK-3ß, and activation of ß-catenin signaling in cancer cells. Through its effect on ß-catenin signaling, AIF inhibits epithelial-mesenchymal transition (EMT) and metastasis of cancer cells in vitro and in orthotopically implanted xenografts. Accordingly, the expression of AIF is correlated with the survival of human patients with cancers of multiple origins. These results identify PTEN as the substrate of AIF oxidoreductase and reveal a novel function for AIF in controlling tumor metastasis.


Assuntos
Fator de Indução de Apoptose/metabolismo , Metástase Neoplásica/fisiopatologia , PTEN Fosfo-Hidrolase/metabolismo , Domínios e Motivos de Interação entre Proteínas , beta Catenina/metabolismo , Fator de Indução de Apoptose/genética , Transição Epitelial-Mesenquimal , Técnicas de Silenciamento de Genes , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Células HEK293 , Xenoenxertos , Humanos , Mitocôndrias/química , Oxirredução , Oxirredutases/metabolismo , PTEN Fosfo-Hidrolase/genética , Fosforilação
14.
Carcinogenesis ; 37(11): 1079-1088, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27543779

RESUMO

Recently, we have reported that apoptosis-inducing factor (AIF) regulates the epithelial-mesenchymal transition (EMT) process of cancers, but the mechanisms underlying the regulation of AIF expression in cancers remain greatly unknown. Here, we report that hypoxia inversely correlates with the expression of AIF in tumor tissues from a cohort of colon cancer patients and inhibits AIF expression in multiple colon cancer cell lines. This inhibition is mediated by hypoxia-inducible factor-1 (HIF-1), which transcriptionally represses AIF through direct binding to the hypoxia-response element in AIF promoter as revealed by luciferase reporter and chromatin immunoprecipitation assays. We also show that downregulation of AIF contributes to hypoxia-induced EMT as overexpression or silencing of AIF partially reverses or potentiates the EMT program initiated by hypoxic treatment. Mechanistic study reveals that downregulation of AIF by hypoxia causes oxidative inactivation of the lipid phosphatase activity of phosphatase and tensin homolog on chromosome 10 (PTEN), with ensuing activation of Akt kinase, phosphorylation of the Akt substrate GSK-3ß and activation of WNT/ß-catenin signaling in colon cancer cells. These results identify AIF as a novel target gene of HIF-1 and reveal the role of AIF downregulation in hypoxia-induced EMT.


Assuntos
Fator de Indução de Apoptose/genética , Neoplasias do Colo/metabolismo , Transição Epitelial-Mesenquimal , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Animais , Fator de Indução de Apoptose/metabolismo , Sequência de Bases , Sítios de Ligação , Hipóxia Celular , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Regulação para Baixo , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Oxirredução , PTEN Fosfo-Hidrolase/metabolismo , Regiões Promotoras Genéticas , Via de Sinalização Wnt
15.
Chemistry ; 20(52): 17523-9, 2014 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-25346404

RESUMO

Core-shell hierarchical porous carbon spheres (HPCs) were synthesized by a facile hydrothermal method and used as host to incorporate sulfur. The microstructure, morphology, and specific surface areas of the resultant samples have been systematically characterized. The results indicate that most of sulfur is well dispersed over the core area of HPCs after the impregnation of sulfur. Meanwhile, the shell of HPCs with void pores is serving as a retard against the dissolution of lithium polysulfides. This structure can enhance the transport of electron and lithium ions as well as alleviate the stress caused by volume change during the charge-discharge process. The as-prepared HPC-sulfur (HPC-S) composite with 65.3 wt % sulfur delivers a high specific capacity of 1397.9 mA h g(-1) at a current density of 335 mA g(-1) (0.2 C) as a cathode material for lithium-sulfur (Li-S) batteries, and the discharge capacity of the electrode could still reach 753.2 mA h g(-1) at 6700 mA g(-1) (4 C). Moreover, the composite electrode exhibited an excellent cycling capacity of 830.5 mA h g(-1) after 200 cycles.

16.
Chin Med Sci J ; 29(1): 61-2, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24698683

RESUMO

PATIENTS with chronic heart failure (CHF) have a high incidence of atrial/ventricular arrhythmias which seriously affect life span and quality of life. Cardiac re-synchronization therapy (CRT) can improve cardiac function and reverse myocardial remodeling, therefore improving the quality of life and reducing mortality. CRT with Home-Monitoring (HM) can be used to monitor cardiac arrhythmias and other heart physiological indexes such as intrathoracic impedance and hemodynamics. Through wireless satellites, the data from the patients are sent to a monitor center for analysis. Doctors can identify emergent information and make a rapid diagnosis based on the information stored in the monitor center. CRT with HM has been verified as a valid method to optimize drug treatment according to individual parameters.


Assuntos
Terapia de Ressincronização Cardíaca/métodos , Insuficiência Cardíaca/tratamento farmacológico , Tecnologia de Sensoriamento Remoto/métodos , Dispositivos de Terapia de Ressincronização Cardíaca , Doença Crônica , Testes de Função Cardíaca , Humanos , Tecnologia de Sensoriamento Remoto/instrumentação , Resultado do Tratamento
17.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(3): 875-882, 2024 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-38926983

RESUMO

OBJECTIVE: This study was aimed to provide ideas for identifying the antibodies to high-frequency antigens by analyzing a female case of high-frequency antigen antibody (anti-Ku) using serological and sequencing method. METHODS: The methods for identification of blood group, erythrocyte antigen, screening and identification of antibody were used to detect the blood type and antibody in the proband. The proband's serum and reagent screening cells treated with Sulfhydryl reagent were applied to judge the type and characteristics of this antibodies when reacted with the regaent screening cells or proband's serum respectively. Gene sequencing was used to determine the genotype of the proband's blood group. RESULTS: The proband's red blood cells were determined as O type RhD positive, whose serum showed strong positive reaction to antibody-screening cells and antibody identification cells with the same intensity in saline and IAT medium, however, the self-cells showed negative effect. The Direct Antihuman Globulin of proband's red blood cells also showed weak positive reaction, and the other blood types were CcEe, Jk(a+b-), P1-, Le(a-b -), Lu (a-b +), K-, k-, Kp(a-b-). Serum of the proband treated with 2-ME still react with three groups of screening cells in IAT medium. The reaction intensity of proband's serum was also unchanged with the cells modified with papain and bromelain, but showed negative effect when the cells were treated with sulfhydryl agents including DTT and 2-ME. Gene sequencing revealed that the KEL genotype of the patient was KEL*02N.24 . This patient had a rare K0 phenotype. CONCLUSION: The rare Kell-null blood group (also known as K0) were identified by serological and molecular tests in the proband who produced both IgG and IgM type of antibody to high-frequency antigen (anti-Ku). These two methods are of great significance in the identification of this rare blood group as well as the antibody to high frequency antigen.


Assuntos
Eritrócitos , Humanos , Feminino , Eritrócitos/imunologia , Antígenos de Grupos Sanguíneos/imunologia , Tipagem e Reações Cruzadas Sanguíneas , Genótipo , Autoantígeno Ku/imunologia , Anticorpos
18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(1): 27-32, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38387895

RESUMO

OBJECTIVE: To investigate the clinical significance of genetic and molecular changes in primary myeloid sarcoma (MS). METHODS: Fourteen patients with primary MS were selected in Jiading District Central Hospital Affiliated Shanghai University of Medicine & Health Sciences, The First People's Hospital of Lianyungang from September 2010 to December 2021. AML1-ETO fusion, PML-RARα fusion and CBFß breakage were detected by fluorescence in situ hybridization (FISH), and the mutations of NPM1, CEBPA, FLT3, RUNX1, ASXL1, KIT and TP53 genes were detected by new generation sequencing (NGS). RESULTS: Among 14 patients, the MS occurred in bone, breast, epididymis, lung, chest wall, cervix, small intestine, ovary, lymph nodes and central nervous system. The tumor cells expressed MPO (13 cases), CD34 (7 cases), CD43 (8 cases), CD68 (7 cases), CD99 (8 cases) and CD117 (6 cases). Cytogenetic abnormalities were observed in 4 cases, including 3 cases of AML1-ETO fusion and 1 case of CBFß breakage, while no PML-RARα fusion was detected. There were no significant differences in overall survival (OS) and leukemia-free survival (LFS) between patients with and without AML1-ETO fusion/CBFß breakage (both P >0.05). Among the 14 patients, the number of NPM1, CEBPA, FLT3-ITD, RUNX1, ASXL1, KIT and TP53 gene mutations was 5, 3, 5, 3, 2, 2, 1, respectively, of which 7 cases had at least one mutation in FLT3-ITD, RUNX1, ASXL1 and TP53 gene. The OS and LFS of patients with FLT3-ITD, RUNX1, ASXL1 or TP53 mutation were shorter than those without mutations (both P <0.01). CONCLUSION: The genetic and molecular abnormalities of primary MS can be detected by FISH and NGS techniques. FLT3-ITD, RUNX1, ASXL1 or TP53 mutation indicates a worse prognosis, but further clinical studies are needed to confirm it.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core , Sarcoma Mieloide , Masculino , Feminino , Humanos , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Nucleofosmina , Relevância Clínica , Hibridização in Situ Fluorescente , China
19.
Sci Adv ; 10(5): eadi7284, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38295161

RESUMO

The end-Permian mass extinction was the most severe ecological event during the Phanerozoic and has long been presumed contemporaneous across terrestrial and marine realms with global environmental deterioration triggered by the Siberian Traps Large Igneous Province. We present high-precision zircon U-Pb geochronology by the chemical abrasion-isotope dilution-thermal ionization mass spectrometry technique on tuffs from terrestrial to transitional coastal settings in Southwest China, which reveals a protracted collapse of the Cathaysian rainforest beginning after the onset of the end-Permian marine extinction. Integrated with high-resolution geochronology from coeval successions, our results suggest that the terrestrial extinction occurred diachronously with latitude, beginning at high latitudes during the late Changhsingian and progressing to the tropics by the early Induan, spanning a duration of nearly 1 million years. This latitudinal age gradient may have been related to variations in surface warming with more degraded environmental conditions at higher latitudes contributing to higher extinction rates.

20.
Protein Cell ; 15(7): 512-529, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38167949

RESUMO

Polycystic ovary syndrome (PCOS) is the leading cause of anovulatory infertility. Inadequate understanding of the ovulation drivers hinders PCOS intervention. Herein, we report that follicle stimulating hormone (FSH) controls follicular fluid (FF) glutamine levels to determine ovulation. Murine ovulation starts from FF-exposing granulosa cell (GC) apoptosis. FF glutamine, which decreases in pre-ovulation porcine FF, elevates in PCOS patients FF. High-glutamine chow to elevate FF glutamine inhibits mouse GC apoptosis and induces hormonal, metabolic, and morphologic PCOS traits. Mechanistically, follicle-development-driving FSH promotes GC glutamine synthesis to elevate FF glutamine, which maintain follicle wall integrity by inhibiting GC apoptosis through inactivating ASK1-JNK apoptotic pathway. FSH and glutamine inhibit the rapture of cultured murine follicles. Glutamine removal or ASK1-JNK pathway activation with metformin or AT-101 reversed PCOS traits in PCOS models that are induced with either glutamine or EsR1-KO. These suggest that glutamine, FSH, and ASK1-JNK pathway are targetable to alleviate PCOS.


Assuntos
Hormônio Foliculoestimulante , Glutamina , Células da Granulosa , Ovulação , Síndrome do Ovário Policístico , Animais , Feminino , Células da Granulosa/metabolismo , Células da Granulosa/efeitos dos fármacos , Glutamina/metabolismo , Camundongos , Hormônio Foliculoestimulante/metabolismo , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Humanos , Apoptose/efeitos dos fármacos , MAP Quinase Quinase Quinase 5/metabolismo , MAP Quinase Quinase Quinase 5/genética , Suínos , Camundongos Endogâmicos C57BL
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