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1.
Cell Mol Life Sci ; 80(4): 87, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36917255

RESUMO

Membrane trafficking processes regulate the G protein-coupled receptor activity. The muscarinic acetylcholine receptors (mAChRs) are highly pursued drug targets for neurological diseases, but the cellular machineries that control the trafficking of these receptors remain largely elusive. Here, we revealed the role of the small GTPase Rab10 as a negative regulator for the post-activation trafficking of M4 mAChR and the underlying mechanism. We show that constitutively active Rab10 arrests the receptor within Rab5-positive early endosomes and significantly hinders the resensitization of M4-mediated Ca2+ signaling. Mechanistically, M4 binds to Rab10-GTP, which requires the motif 386RKKRQMAA393 (R386-A393) within the third intracellular loop. Moreover, Rab10-GTP inactivates Arf6 by recruiting the Arf6 GTPase-activating protein, ACAP1. Strikingly, deletion of the motif R386-A393 causes M4 to bypass the control by Rab10 and switch to the Rab4-facilitated fast recycling pathway, thus reusing the receptor. Therefore, Rab10 couples the cargo sorting and membrane trafficking regulation through cycle between GTP-bound and GDP-bound state. Our findings suggest a model that Rab10 binds to the M4 like a molecular brake and controls the receptor's transport through endosomes, thus modulating the signaling, and this regulation is specific among the mAChR subtypes.


Assuntos
GTP Fosfo-Hidrolases , Receptores Muscarínicos , GTP Fosfo-Hidrolases/metabolismo , Membrana Celular/metabolismo , Receptores Muscarínicos/metabolismo , Transdução de Sinais , Endossomos/metabolismo , Proteínas de Transporte/metabolismo , Guanosina Trifosfato/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo
2.
J Sep Sci ; 47(5): e2300865, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38471971

RESUMO

A novel coating for stir bar sorptive extraction was developed by growing a covalent organic framework, TpPa-1 (derived from phenylenediamine and 1,3,5-trimethylphloroglucinol), onto the surface of Ni-Al layered double hydroxide. Using a poly(ether ether ketone) tube as the supporting substrate, a TpPa-1/layered double hydroxide-coated stir bar was fabricated and demonstrated excellent extraction performance for Sudan dyes. Notably, its extraction efficiency significantly exceeded that of stir bars modified with only TpPa-1 or Ni-Al layered double hydroxide. Based on this innovative coating, a stir bar sorptive extraction-high performance liquid chromatography method was established. This method exhibited low limits of detection (0.04-0.08 ng/mL) for the analysis of Sudan dyes. It also featured a wide linear range (0.25-100 or 200 ng/mL) and demonstrated good repeatability with relative standard deviations ≤6.22%. The recoveries obtained for spiked lake water and chili powder samples were 93.5%-105.2% and 87.8%-100.6%, respectively, demonstrating the practical potential of the developed method for detecting trace Sudan dyes in real samples.

3.
Clin Genet ; 103(4): 392-400, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36527336

RESUMO

Genome-wide association studies (GWAS) have identified a large number of single nucleotide polymorphism (SNP) sites associated with human diseases. In the annotation of human diseases, especially cancers, SNPs, as an important component of genetic factors, have gained increasing attention. Given that most of the SNPs are located in non-coding regions, the functional verification of these SNPs is a great challenge. The key to functional annotation for risk SNPs is to screen SNPs with regulatory activity from thousands of disease associated-SNPs. In this review, we systematically recapitulate the characteristics and functional roles of SNP sites, discuss three parallel reporter screening strategies in detail based on barcode tag classification, and recommend the common in silico strategies to help supplement the annotation of SNP sites with epigenetic activity analysis, prediction of target genes and trans-acting factors. We hope that this review will contribute to this exuberant research field by providing robust activity analysis strategies that can facilitate the translation of GWAS results into personalized diagnosis and prevention measures for human diseases.


Assuntos
Estudo de Associação Genômica Ampla , Neoplasias , Humanos , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença
4.
Cell Mol Neurobiol ; 43(6): 2925-2937, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36913114

RESUMO

Nerve tissue regeneration is a significant problem. After neural diseases and damage such as spinal cord injury (SCI), the accumulation of chondroitin sulfate proteoglycans (CSPG) comprising axonal inhibitory glycosaminoglycan chains in the microenvironment is a major barrier that obstructs nerve repair. Interfering with the production of glycosaminoglycans, especially the critical inhibitory chains, could be a potential therapeutic strategy for SCI, which is, however, poorly defined. This study identifies Chst15, the chondroitin sulfotransferase controlling the generation of axonal inhibitory chondroitin sulfate-E, as a therapeutic target of SCI. Using a recently reported small molecular Chst15 inhibitor, this study investigates the effects of Chst15 inhibition on astrocyte behaviors and the associated consequences of in vivo disruption of the inhibitory microenvironment. Deposition of CSPGs in the extracellular matrix and migration of astrocytes are both significantly impaired by Chst15 inhibition. Administration of the inhibitor in transected spinal cord tissues of rats effectively promotes motor functional restoration and nerve tissue regeneration by a mechanism related to the attenuation of inhibitory CSPGs, glial scar formation and inflammatory responses. This study highlights the role of Chst15 in the CSPG-mediated inhibition of neural recovery after SCI and proposes an effective neuroregenerative therapeutic strategy that uses Chst15 as a potential target.


Assuntos
Astrócitos , Traumatismos da Medula Espinal , Ratos , Animais , Proteoglicanas de Sulfatos de Condroitina , Traumatismos da Medula Espinal/tratamento farmacológico , Axônios , Medula Espinal , Regeneração Nervosa , Carboidrato Sulfotransferases
5.
J Sep Sci ; 46(2): e2200613, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36446729

RESUMO

A novel magnetic sulfonated covalent organic polymer was prepared for magnetic solid-phase extraction of protoberberine alkaloids. The magnetic sulfonated covalent organic polymer was rapidly synthesized under mild conditions. The physicochemical properties of the prepared materials were characterized by Fourier-transform infrared spectrometry, transmission electron microscopy, and X-ray photoelectron spectroscopy. Several extraction parameters were systematically investigated, including desorption time, pH of sample solution, acetonitrile content, acetic acid content in the eluent, extraction time, and sample volume. By coupling magnetic solid-phase extraction and high-performance liquid chromatography, an efficient and sensitive method for the extraction and determination of protoberberine alkaloids in complex samples was developed. The proposed method showed great linearity (r > 0.9989), low limits of detection (0.2-0.3 ng/ml), and high precision (relative standard deviations ≤ 5.74%). The proposed method was further applied to the analysis of protoberberine alkaloids in Cortex phellodendri and human plasma samples. The recoveries were 91.50%-110.31% with relative standard deviations less than 6.63% in Cortex phellodendri and 96.12%-111.20% with relative standard deviations lower than 5.56% in plasma samples.


Assuntos
Alcaloides , Polímeros , Humanos , Polímeros/química , Adsorção , Fenômenos Magnéticos , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Limite de Detecção
6.
Tohoku J Exp Med ; 258(1): 35-41, 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35705319

RESUMO

Ischemic heart disease and the resulting heart failure remain the leading causes of death and disability worldwide. This study aimed to investigate the role of miR-1229-5p in serum extracellular vesicles (EVs) mediated myocardial protection by constructing a hypoxia/reoxygenation model (HR) in H9c2 cells. Cardiomyocytes were cultured and divided into different treatment groups: control group, HR group, serum-EVs group, and serum-EVs + miR-1229-5p inhibitor group. The expression levels of miR-1229-5p were detected using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The changes in cell proliferation and apoptosis were detected by MTT assay and flow cytometry. The myocardial injury-related indicators, cardiac troponin I (cTnI), creatinine kinase MB (CK-MB), and lactate dehydrogenase (LDH), were measured by enzyme-linked immunosorbent assay (ELISA). Finally, the luciferase reporter assay was used to verify the miR-1229-5p target. The proliferation of myocardial cells in the HR group was reduced, the number of apoptotic cells was increased, and myocardial injury indicators concentration was decreased. Transfection of miR-1229-5p inhibitor under serum-EVs treatment reduced the protective effect of serum-EVs on myocardial cell injury, decreased cell proliferation, increased the number of apoptotic cells, and increased myocardial injury indicator concentration. Additionally, FOXO4 may be the target of miR-1229-5p. Our data suggest that serum-EVs alleviate HR-induced cardiomyocyte injury by regulating miR-1229-5p/FOXO4.


Assuntos
Vesículas Extracelulares , MicroRNAs , Traumatismo por Reperfusão Miocárdica , Apoptose/genética , Vesículas Extracelulares/metabolismo , Humanos , Hipóxia/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo
7.
J Biol Chem ; 294(29): 11119-11130, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31167779

RESUMO

Following the accumulation of improperly folded proteins in the endoplasmic reticulum (ER), a condition known as ER stress in this compartment triggers an adaptive signaling pathway referred to as the unfolded protein response (UPR). The UPR aims at restoring ER homeostasis; if the ER stress cannot be resolved, apoptosis is triggered. However, the mechanisms responsible for regulating the balance between cell life and death decisions that occur after exposure to ER stress remain unclear. Protein kinase D1 (PKD1) has been reported to initiate protective signaling against oxidative stress or ischemia, two conditions that impinge on the induction of ER stress. In addition, the high levels of expression of PKD1, observed in highly proliferative cancers and tumors with poor prognosis, contribute to enhanced resistance to chemotherapy. In this study, we show that the ER stress inducers tunicamycin and thapsigargin lead to the activation of PKD1 in human prostate cancer PC-3 cells and in hepatoma HepG2 cells through a PKCδ-dependent mechanism. Moreover, our data indicate that PKD1 is required for the stabilization of inositol-requiring enzyme 1 (IRE1) and the subsequent regulation of its activity. PKD1 activation contributes to the phosphorylation of mitogen-activated protein kinase phosphatase 1, resulting in decreased IRE1-mediated c-Jun N-terminal kinase activation. This study unveils the existence of a novel PKD1-dependent prosurvival mechanism that is activated upon ER stress and selectively enhances IRE1 prosurvival signaling.


Assuntos
Endorribonucleases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Canais de Cátion TRPP/metabolismo , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ativação Enzimática , Humanos , MAP Quinase Quinase 4/metabolismo , Proteína Quinase C-delta/metabolismo , Estabilidade Proteica , Tapsigargina/farmacologia , Tunicamicina/farmacologia , Resposta a Proteínas não Dobradas
8.
Cell Physiol Biochem ; 46(4): 1536-1554, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29689560

RESUMO

BACKGROUND/AIMS: This study determined the role and mechanism of action of transcription factor EB (TFEB) in H2O2-induced neuronal apoptosis. METHODS: SH-SY5Y cells were treated with Akt inhibitor/activator and different concentrations of H2O2. Cell apoptosis was detected by flow cytometric analysis. Akt and TFEB phosphorylation and PARP cleavage were determined by Western blotting. HEK293T cells were transfected with different truncated TFEB mutants and HA-Akt-WT; SH-SY5Y cells were transfected with Flag-vector, Flag-TFEB, Flag-TFEB-S467A or Flag-TFEB-S467D; and TFEB interaction with Akt was determined by co-immunoprecipitation and GST pull-down assays. RESULTS: A low concentration of H2O2 induces TFEB phosphorylation at Ser467 and nuclear translocation, facilitating neuronal survival, whereas a high concentration of H2O2 promotes SH-SY5Y cell apoptosis via suppressing TFEB Ser467 phosphorylation and nuclear translocation. The TFEB-S467D mutant is more easily translocated into the nucleus than the non-phosphorylated TFEB-S467A mutant. Further, Akt physically binds to TFEB via its C-terminal tail interaction with the HLH domain of TFEB and phosphorylates TFEB at Ser467. Mutation of TFEB-Ser467 can prevent the phosphorylation of TFEB by Akt, preventing inhibition of oxidative stress-induced apoptosis. CONCLUSIONS: Oxidative stress induces neuronal apoptosis through suppressing TFEB phosphorylation at Ser467 by Akt, providing a novel therapeutic strategy for neurodegenerative diseases.


Assuntos
Apoptose/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Peróxido de Hidrogênio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Androstadienos/farmacologia , Animais , Linhagem Celular Tumoral , Flavonoides/farmacologia , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Neurônios/citologia , Neurônios/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Wortmanina
9.
Cell Biol Int ; 42(11): 1511-1522, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30080297

RESUMO

Proliferation of the adult hepatocyte population represents a central feature of tissue regeneration after liver injury and resection. This process could be driven by a diverse range of mitogens, such as hepatocyte growth factor (HGF) and fibroblast growth factor (FGF). Among FGF family, FGF2 is closely related to wound repair and cell proliferation. FGF2 does function in the process of angiogenesis in regenerating liver, while fewer reports are concerned with the impact and underlying mechanism of FGF2 on liver cell proliferation. To this end, an immortalized human normal hepatocyte L02 and mouse primary hepatocytes were exposed to FGF2 in this study. We demonstrate that FGF2 significantly enhances liver cell proliferation. Treatment with FGF2 obviously increases the phosphorylation level of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and c-Jun N-terminal kinase (JNK). Activity inhibition or expression down-regulation prove that both ERK1/2 and JNK signaling are required for FGF2-mediated effect on liver cell proliferation. Interestingly, interfering of ERK1/2 signaling results in marked decrease of JNK activation under FGF2 treatment, and JNK signaling is also involved in regulation of FGF2-induced ERK1/2 activation, suggesting that cross-talk between ERK1/2 and JNK signaling is important for FGF2 mitogenic activity. Both ERK1/2 and JNK signal via CREB to function in proliferation impact of FGF2 on liver cells. Taken together, this study reveals that ERK and JNK pathways synergistically regulate FGF2-induced liver cell proliferation via phosphorylating CREB, which will contribute to the understanding of FGF2 impact on liver cell proliferation and liver regeneration.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Fígado/citologia , Sistema de Sinalização das MAP Quinases , Mitógenos/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ativação Enzimática/efeitos dos fármacos , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Modelos Biológicos
10.
Pain Med ; 16(11): 2162-70, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26744887

RESUMO

OBJECTIVES: Postherpetic neuralgia (PHN) is one of the most intractable pain disorders, especially in elderly patients. There is evidence that repetitive transcranial magnetic stimulation (rTMS) reduces neuropathic pain; however, its effectiveness for PHN is unknown. This study investigated the efficacy of high-frequency rTMS in patients with PHN. DESIGN: A total of 40 patients were randomly assigned to receive 10 sessions of real or sham rTMS of the primary motor cortex. Each stimulation session consisted of a series of 300 five-second pulses with a frequency of 10 Hz and an interval of 3 seconds between each train, giving a total of 1500 pulses per session. The primary outcome was pain intensity measured before stimulation from first intervention (T0) to the final stimulation (T10), and 1 and 3 months after final stimulation (T11 and T12). Other outcomes measured included scores on the short form McGill pain questionnaire, self-rating depression scale, quality of life (QOL), sleep quality, the patient global impression of change, medication regulation, and reported adverse events. RESULTS: The real rTMS group demonstrated greater reduction of visual analogue scale (VAS) than the sham group at each time point except for T0 (P = 0.399) and T1 (P = 0.091). Mean VAS reduction in the real rTMS group was 16.89% for duration of disease longer than 6 months. These analgesic effects were associated with long-term improvement in rating-scale items related to QOL. CONCLUSION: The results suggest that rTMS is an effective and safe therapy in patients with PHN.


Assuntos
Córtex Motor/fisiopatologia , Neuralgia Pós-Herpética/terapia , Neuralgia/terapia , Estimulação Magnética Transcraniana , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Neuralgia Pós-Herpética/diagnóstico , Medição da Dor , Qualidade de Vida , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento
11.
Mediators Inflamm ; 2014: 190860, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24701032

RESUMO

BACKGROUND & AIMS: AIM2 plays an important role in innate immunity, but its role in regulating the immune response to hepatitis B virus (HBV) is unknown. We hypothesized that AIM2 expression is positively correlated with HBV-mediated inflammation in patients with HBV-associated glomerulonephritis (HBV-GN), potentiating inflammation and leading to renal damage. We therefore analyzed the expression of AIM2 and inflammatory factors in HBV-GN tissues and cell lines relative to the inflammatory response to HBV infection and HBV status. METHODS: Seventy-nine patients with chronic nephritis (CN) were included: 54 with HBV-GN and 24 with chronic glomerulonephritis (CGN). Expression of AIM2, caspase-1, and IL-1ß was detected by immunohistochemistry in renal biopsies from each patient. Following siRNA-mediated knockdown of AIM2 in HBV-infected and HBV-uninfected human glomerular mesangial (HGM) cells, expression of caspase-1, IL-1ß, and IL-18 was detected by qRT-PCR and Western blot. RESULTS: AIM2 expression in HBV-GN biopsies (81.4%) was significantly higher than in CGN (4.0%) and positively correlated with caspase-1 and IL-1ß expression in HBV-GN. In vitro, AIM2 knockdown reduced caspase-1, IL-1ß, and IL-18 expression in HBV-infected and HBV-uninfected HGM cells. CONCLUSION: AIM2 elevation during HBV infection or replication may contribute to inflammatory damage, thus providing a putative therapeutic target for HBV-GN.


Assuntos
Caspase 1/metabolismo , Proteínas de Ligação a DNA/metabolismo , Glomerulonefrite/metabolismo , Hepatite B/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Biópsia , Glomerulonefrite/complicações , Hepatite B/complicações , Vírus da Hepatite B , Humanos , Imuno-Histoquímica , Inflamação , Rim/metabolismo , Células Mesangiais/citologia , RNA Interferente Pequeno/metabolismo , Estudos Retrospectivos
12.
Artigo em Inglês | MEDLINE | ID: mdl-38261504

RESUMO

Anomaly detection, the task of differentiating abnormal data points from normal ones, presents a significant challenge in the realm of machine learning. Numerous strategies have been proposed to tackle this task, with classification-based methods, specifically those utilizing a self-supervised approach via random affine transformations (RATs), demonstrating remarkable performance on both image and non-image data. However, these methods encounter a notable bottleneck, the overlap of constructed labeled datasets across categories, which hampers the subsequent classifiers' ability to detect anomalies. Consequently, the creation of an effective data distribution becomes the pivotal factor for success. In this article, we introduce a model called "self-supervised forest (sForest)", which leverages the random Fourier transform (RFT) and random orthogonal rotations to craft a controlled data distribution. Our model utilizes the RFT to map input data into a new feature space. With this transformed data, we create a self-labeled training dataset using random orthogonal rotations. We theoretically prove that the data distribution formulated by our methodology is more stable compared to one derived from RATs. We then use the self-labeled dataset in a random forest (RF) classifier to distinguish between normal and anomalous data points. Comprehensive experiments conducted on both real and artificial datasets illustrate that sForest outperforms other anomaly detection methods, including distance-based, kernel-based, forest-based, and network-based benchmarks.

13.
Commun Biol ; 7(1): 501, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664468

RESUMO

G protein-coupled receptors naturally oscillate between inactive and active states, often resulting in receptor constitutive activity with important physiological consequences. Among the class C G protein-coupled receptors that typically sense amino-acids and their derivatives, the calcium sensing receptor (CaSR) tightly controls blood calcium levels. Its constitutive activity has not yet been studied. Here, we demonstrate the importance of the inter-subunit disulfide bridges in maintaining the inactive state of CaSR, resulting in undetectable constitutive activity, unlike the other class C receptors. Deletion of these disulfide bridges results in strong constitutive activity that is abolished by mutations preventing amino acid binding. It shows that this inter-subunit disulfide link is necessary to limit the agonist effect of amino acids on CaSR. Furthermore, human genetic mutations deleting these bridges and associated with hypocalcemia result in elevated CaSR constitutive activity. These results highlight the physiological importance of fine tuning the constitutive activity of G protein-coupled receptors.


Assuntos
Dissulfetos , Receptores de Detecção de Cálcio , Receptores de Detecção de Cálcio/metabolismo , Receptores de Detecção de Cálcio/genética , Humanos , Dissulfetos/metabolismo , Dissulfetos/química , Células HEK293 , Cálcio/metabolismo , Mutação , Animais
14.
J Med Chem ; 67(4): 2487-2511, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38316747

RESUMO

AMG510, as the first approved inhibitor for KRASG12C mutation, has shown promising efficacy in nonsmall-cell lung cancer and colorectal cancer harboring KRASG12C mutation. However, the moderate response rate and the rapid emergence of acquired resistance limit the therapeutic potential of AMG510, highlighting the need for the development of combination strategies. Here, we observed the suppression of RAS-MAPK signaling induced by AMG510 was prolonged and enhanced by SOS1 knockdown. Thus, we design, synthesize, and characterize a potent and specific SOS1 degrader 23. Compound 23 showed efficient SOS1 degradation in KRAS-driven cancer cells and achieved significant antiproliferative potency. Importantly, the combination of 23 with AMG510 suppressed RAS signaling feedback activation, showing synergistic effects against KRASG12C mutant cells in vitro and in vivo. Our findings demonstrated that KRASG12C inhibition plus SOS1 degradation as a potential therapeutic strategy to improve antitumor response and overcome acquired resistance to KRASG12C inhibitor.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Mutação , Neoplasias Pulmonares/tratamento farmacológico
15.
BMC Infect Dis ; 13: 394, 2013 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23977980

RESUMO

BACKGROUND: Reactivation of hepatitis B virus (HBV), characterized by increased levels of serum HBV DNA, abnormal liver function and hepatic failure, is a frequent complication of immunosuppressive therapy and chemotherapy in patients with HBV infection. However, reactivation of occult HBV infection with immunosuppressive therapy or chemotherapy is rare. CASE PRESENTATION: A 77-year-old man was diagnosed with nephrotic syndrome and IgM nephropathy with unclear pathogenesis. Liver function was normal, HBV-related serum markers were negative and HBV DNA titer was below the upper limits of normal. Two months following the start of prednisone therapy for his nephrotic syndrome, laboratory tests revealed a substantial increase in serum transaminase levels (ALT: 490 IU/L; AST: 149 IU/L) and an elevation of HBV DNA level (3.42×10(6) copies/ml). We tested stored kidney tissue for HBsAg and HBcAg using immunohistochemistry and found the sample to be HBcAg positive, allowing us to confirm the etiology of nephropathy as an occult HBV infection. The cause of the hepatitis was thought to be HBV reactivation, so we immediately administered lamivudine. One month after the initiation of daily lamivudine treatment, laboratory tests revealed that serum levels of transaminases had improved (ALT: 35 IU/L; AST: 17 IU/L). Patient examination one year later showed that HBeAg had decreased with a concomitant increase of HBeAb, the quantity of HBV DNA was undetectable, and liver function and renal function had stabilized. CONCLUSION: This is the first report describing HBV reactivation in an occult HBV infection patient treated with oral prednisone for nephrotic syndrome. HBV-associated antigen should be regularly tested for in patients with unknown etiological glomerulonephritis in areas with high HBV viral popular and even in those with no clinical evidence for diagnosis of HBV.


Assuntos
Hepatite B/virologia , Síndrome Nefrótica/tratamento farmacológico , Síndrome Nefrótica/virologia , Prednisona/administração & dosagem , Idoso , DNA Viral/sangue , Humanos , Glomérulos Renais/patologia , Masculino , Prednisona/efeitos adversos , Recidiva
16.
Front Chem ; 11: 1121724, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36733715

RESUMO

Bladder cancer is the most common malignancy of the urinary system. Efforts to identify innovative and effective therapies for bladder cancer are urgently needed. Recent studies have identified the BRD4 protein as the critical factor in regulation of cell proliferation and apoptosis in bladder cancer, and it shows promising potential for pharmacologic treatment against bladder cancer. In this study, we have evaluated the biological function of QCA570, a novel BET degrader, on multiple bladder cancer cells and explore its underlying mechanisms. QCA570 potently induces degradation of BRD4 protein at nanomolar concentrations, with a DC50 of ∼ 1 nM. It decreases EZH2 and c-MYC levels by transcriptional suppression and protein degradation. Moreover, the degrader significantly induces cell apoptosis and cycle arrest and shows antiproliferation activity against bladder cancer cells. These findings support the potential efficacy of QCA570 on bladder cancer.

17.
PeerJ ; 11: e14689, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36718442

RESUMO

Background: Stevia straw is a byproduct of sugar crop stevia. It is a good feed material because of richness in nutrients and active substances (steviosides and flavonoids). However, due to improper utilization such as piling, burning and so on, it became a large amount of wasted straw resources and lead to environmental pollution. Methods: We added 0%, 0.2%, 0.4%, 0.6%, 0.8%, 1.0% and 1.5% of stevia stalk to study the effects of different stevia stalk concentrations on nutrient utilization and rumen fermentation in sheep (based on sheep diet). In vitro fermentation method was used, with 17 repetitions for each treatment. All fermentation substrate based on sheep diet with different stevia stalk concentrations were fermented for 2 h, 6 h, 12 h, 24 h and 48 h, then the gas production, dry matter degradability (DMD), crude protein degradability (CPD), neutral detergent fiber degradability (NDFD), acid detergent fiber degradability (ADFD), pH, ammonia nitrogen (NH3-N) and volatile fatty acids (VFAs) were determined. Results: The results showed that at different fermentation time, the change trend of gas production in each teatment was basically same, but the maximum occurred in 1.0% treatment at 48 h. The DMD, CPD, NDFD and ADFD of sheep diets increased with fermentation time increasing, especially the CPD48h, NDFD48h and ADFD48h of diets in 0.8%, 1.0% and 1.5% treatments were significantly higher than those in control (P < 0.05). The pH of fermentation substrate in each treatment remained within the normal range of 6.21∼7.25. NH3-N24h-48hin 0.8%, 1.0% and 1.5% treatments were higher than that in control. At 6 h-12 h, the total acid content of 0.8% and 1.0% treatments were significantly higher than those of other treatments (P < 0.05), it reached the highest in 1.0% treatment. According to overall evaluation, effect ranking of stevia stalk on sheep nutrient utilization was as follows: 1.0% >0.8% >1.5% >0.4% >0.6% >0.2%. Overall, 1.0% stevia stalk could promote nutrient degradation and sheep rumen fermentation.


Assuntos
Rúmen , Stevia , Ovinos , Animais , Rúmen/metabolismo , Fermentação , Detergentes/metabolismo , Ração Animal/análise , Digestão , Nutrientes
18.
J Med Chem ; 66(16): 11158-11186, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37556600

RESUMO

We report small molecular PROTAC compounds targeting the androgen receptor N-terminal domain (AR-NTD), which were obtained by tethering AR-NTD antagonists and different classes of E3 ligase ligands through chemical linkers. A representative compound, BWA-522, effectively induces degradation of both AR-FL and AR-V7 and is more potent than the corresponding antagonist against prostate cancer (PC) cells in vitro. We have shown that the degradation of AR-FL and AR-V7 proteins by BWA-522 can suppress the expression of AR downstream proteins and induce PC cell apoptosis. BWA-522 achieves 40.5% oral bioavailability in mice and 69.3% in beagle dogs. In a LNCaP xenograft model study, BWA-522 was also proved to be an efficacious PROTAC degrader, resulting in 76% tumor growth inhibition after oral administration of a dose of 60 mg/kg. This study indicates that BWA-522 is a promising AR-NTD PROTAC for the treatment of AR-FL- and AR-V7-dependent tumors.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Quimera de Direcionamento de Proteólise , Animais , Cães , Humanos , Masculino , Camundongos , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Antagonistas de Receptores de Andrógenos/química , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias da Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Receptores Androgênicos/metabolismo , Ubiquitina-Proteína Ligases , Quimera de Direcionamento de Proteólise/química , Quimera de Direcionamento de Proteólise/farmacologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-37279130

RESUMO

Classical domain adaptation methods acquire transferability by regularizing the overall distributional discrepancies between features in the source domain (labeled) and features in the target domain (unlabeled). They often do not differentiate whether the domain differences come from the marginals or the dependence structures. In many business and financial applications, the labeling function usually has different sensitivities to the changes in the marginals versus changes in the dependence structures. Measuring the overall distributional differences will not be discriminative enough in acquiring transferability. Without the needed structural resolution, the learned transfer is less optimal. This article proposes a new domain adaptation approach in which one can measure the differences in the internal dependence structure separately from those in the marginals. By optimizing the relative weights among them, the new regularization strategy greatly relaxes the rigidness of the existing approaches. It allows a learning machine to pay special attention to places where the differences matter the most. Experiments on three real-world datasets show that the improvements are quite notable and robust compared to various benchmark domain adaptation models.

20.
J Med Chem ; 66(7): 4784-4801, 2023 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-36960664

RESUMO

Androgen deprivation in cases of castration-resistant prostate cancer (CRPC) leads to adverse effects, including loss of muscle and bone mass and gain of subcutaneous fat. The tumor-specific suppression of androgen receptor (AR) signaling, while not global, may reduce side effects. We present a class of small-molecular conjugates consisting of an AR antagonist linked to a heat shock protein 90 (Hsp90) inhibitor. We demonstrate that the high accumulation of Hsp90 on the surface of CRPC cells allows uptake of conjugates and increases the enrichment of drugs in the tumor cells. After penetrating prostate cancer cells, the conjugates not only inhibit AR function by the antagonist component but also bind to Hsp90 and suppress the AR protein level. Compared to AR antagonists, these conjugates showed improved tumor-targeting ability and enhanced potency against Enzalutamide-resistant 22Rv1 cells.


Assuntos
Antineoplásicos , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/metabolismo , Antagonistas de Androgênios , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Androgênios , Proteínas de Choque Térmico HSP90 , Nitrilas/uso terapêutico
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