RESUMO
Bromodomain-containing protein 9 (BRD9) is a specific subunit of the non-canonical SWI/SNF (ncBAF) chromatin-remodeling complex, whose function in human embryonic stem cells (hESCs) remains unclear. Here, we demonstrate that impaired BRD9 function reduces the self-renewal capacity of hESCs and alters their differentiation potential. Specifically, BRD9 depletion inhibits meso-endoderm differentiation while promoting neural ectoderm differentiation. Notably, supplementation of NODAL, TGF-ß, Activin A or WNT3A rescues the differentiation defects caused by BRD9 loss. Mechanistically, BRD9 forms a complex with BRD4, SMAD2/3, ß-CATENIN and P300, which regulates the expression of pluripotency genes and the activity of TGF-ß/Nodal/Activin and Wnt signaling pathways. This is achieved by regulating the deposition of H3K27ac on associated genes, thus maintaining and directing hESC differentiation. BRD9-mediated regulation of the TGF-ß/Activin/Nodal pathway is also demonstrated in the development of pancreatic and breast cancer cells. In summary, our study highlights the crucial role of BRD9 in the regulation of hESC self-renewal and differentiation, as well as its participation in the progression of pancreatic and breast cancers.
Assuntos
Células-Tronco Embrionárias Humanas , Neoplasias , Humanos , Fator de Crescimento Transformador beta/genética , Células-Tronco Embrionárias Humanas/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Células-Tronco Embrionárias/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Diferenciação Celular/genética , Ativinas/metabolismo , Via de Sinalização Wnt , Neoplasias/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismoRESUMO
Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS) is associated with congenital absence of the uterus, cervix, and the upper part of the vagina; it is a sex-limited trait. Disrupted development of the Müllerian ducts (MD)/Wölffian ducts (WD) through multifactorial mechanisms has been proposed to underlie MRKHS. In this study, exome sequencing (ES) was performed on a Chinese discovery cohort (442 affected subjects and 941 female control subjects) and a replication MRKHS cohort (150 affected subjects of mixed ethnicity from North America, South America, and Europe). Phenotypic follow-up of the female reproductive system was performed on an additional cohort of PAX8-associated congenital hypothyroidism (CH) (n = 5, Chinese). By analyzing 19 candidate genes essential for MD/WD development, we identified 12 likely gene-disrupting (LGD) variants in 7 genes: PAX8 (n = 4), BMP4 (n = 2), BMP7 (n = 2), TBX6 (n = 1), HOXA10 (n = 1), EMX2 (n = 1), and WNT9B (n = 1), while LGD variants in these genes were not detected in control samples (p = 1.27E-06). Interestingly, a sex-limited penetrance with paternal inheritance was observed in multiple families. One additional PAX8 LGD variant from the replication cohort and two missense variants from both cohorts were revealed to cause loss-of-function of the protein. From the PAX8-associated CH cohort, we identified one individual presenting a syndromic condition characterized by CH and MRKHS (CH-MRKHS). Our study demonstrates the comprehensive utilization of knowledge from developmental biology toward elucidating genetic perturbations, i.e., rare pathogenic alleles involving the same loci, contributing to human birth defects.
Assuntos
Transtornos 46, XX do Desenvolvimento Sexual/genética , Anormalidades Congênitas/genética , Ductos Paramesonéfricos/anormalidades , Ductos Paramesonéfricos/crescimento & desenvolvimento , Mutação , Ductos Mesonéfricos/crescimento & desenvolvimento , Adulto , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 7/genética , Códon sem Sentido , Feminino , Estudos de Associação Genética , Pleiotropia Genética , Proteínas Homeobox A10/genética , Proteínas de Homeodomínio/genética , Humanos , Fator de Transcrição PAX8/genética , Herança Paterna , Penetrância , Proteínas com Domínio T/genética , Fatores de Transcrição/genética , Proteínas Wnt/genética , Ductos Mesonéfricos/anormalidadesRESUMO
In printing, microreactors, and bioassays, the precise control of micrometer-scale droplet generation is essential but challenging, often restricted by the equipment and nozzles used in traditional methods. We introduce a needle-plate electrode corona discharge technique that injects charges into an oil layer, enabling the precise manipulation of droplet polarization and splitting. This method allows for meticulous adjustment of microdroplet formation regarding location, size, and quantity by modulating the discharge voltage, discharge time, and electrode positioning. It enables the immediate initiation and cessation of droplet production, thereby facilitating on-demand droplet generation. Our study on the voltage-dependent droplet stretch coefficient shows that as the voltage increases, the droplets transition from controlled splitting to regular Taylor cone-like ejections, eventually reaching the Rayleigh limit and fully breaking apart. These advancements significantly improve microfluidic droplet manipulation, offering considerable benefits for applications in targeted drug delivery, rapid disease diagnostics, and precise environmental monitoring.
RESUMO
The usage of antiretroviral treatment (ART) has considerably decreased the morbidity and mortality related to HIV-1 (human immunodeficiency virus type 1) infection. However, ART is ineffective in eradicating the virus from the persistent cell reservoirs (e.g., microglia), noticeably hindering the cure for HIV-1. Microglia participate in the progression of neuroinflammation, brain aging, and HIV-1-associated neurocognitive disorder (HAND). Some methods have currently been studied as fundamental strategies targeting microglia. The purpose of this study was to comprehend microglia biology and its functions in HIV-1 infection, as well as to look into potential therapeutic approaches targeting microglia.
Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , Infecções por HIV/tratamento farmacológico , Microglia , EncéfaloRESUMO
BACKGROUND: The gain or loss of large chromosomal regions or even whole chromosomes is termed as genomic scarring and can be observed as copy number variations resulting from the failure of DNA damage repair. RESULTS: In this study, a new algorithm called genomic scar analysis (GSA) has developed and validated to calculate homologous recombination deficiency (HRD) score. The two critical submodules were tree recursion (TR) segmentation and filtering, and the estimation and correction of the tumor purity and ploidy. Then, this study evaluated the rationality of segmentation and genotype identification by the GSA algorithm and compared with other two algorithms, PureCN and ASCAT, found that the segmentation result of GSA algorithm was more logical. In addition, the results indicated that the GSA algorithm had an excellent predictive effect on tumor purity and ploidy, if the tumor purity was more than 20%. Furtherly, this study evaluated the HRD scores and BRCA1/2 deficiency status of 195 clinical samples, and the results indicated that the accuracy was 0.98 (comparing with Affymetrix OncoScan™ assay) and the sensitivity was 95.2% (comparing with BRCA1/2 deficiency status), both were well-behaved. Finally, HRD scores and 16 genes mutations (TP53 and 15 HRR pathway genes) were analyzed in 17 cell lines, the results showed that there was higher frequency in HRR pathway genes in high HRD score samples. CONCLUSIONS: This new algorithm, named as GSA, could effectively and accurately calculate the purity and ploidy of tumor samples through NGS data, and then reflect the degree of genomic instability and large-scale copy number variations of tumor samples.
Assuntos
Variações do Número de Cópias de DNA , Reparo do DNA , Recombinação Homóloga , Algoritmos , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias/genética , PloidiasRESUMO
BACKGROUND Perioperative neuro-cognitive disorders (PND) are preoperative and postoperative complications of multiple nervous systems, typically manifested as decreased memory and learning ability after surgery. It was used to replace the original definition of postoperative cognitive dysfunctions (POCD) from 2018. Our previous studies have shown that sevoflurane inhalation can lead to cognitive dysfunction in Sprague-Dawley rats, but the specific mechanism is still unclear. MATERIAL AND METHODS Thirty-six male Sprague-Dawley rats were randomly divided into 6 groups (n=6): the SD group was given 24-h acute sleep deprivation; Sevoflurane was inhaled for 2 h in the Sevo group. Two mL propofol was injected into the tail vein of rats in the Prop group. The rats in the SD+Sevo group and SD+Prop group were deprived of sleep before intervention in the same way as before. RESULTS We noted significant behavioral changes in rats treated with SIK3 inhibitors or tau phosphorylation agonists before propofol injection or sevoflurane inhalation, with associated protein levels and dendritic spine density documented. Sevoflurane anesthesia-induced cognitive impairment following acute sleep deprivation was more pronounced than sleep deprivation-induced cognitive impairment alone and resulted in increased brain SIK3 levels, increased phosphorylation of total tau and tau, and decreased acetylation modifications. After using propofol, the cognitive function returned to baseline levels with a series of reversals of cognitive dysfunction. CONCLUSIONS These results suggest that sevoflurane inhalation via the SIK3 pathway aggravates cognitive impairment after acute sleep deprivation and that propofol anesthesia reverses the effects of sleep deprivation by affecting modifications of tau protein.
Assuntos
Anestésicos Inalatórios/farmacologia , Anestésicos Intravenosos/farmacologia , Disfunção Cognitiva/fisiopatologia , Plasticidade Neuronal/efeitos dos fármacos , Propofol/farmacologia , Sevoflurano/farmacologia , Privação do Sono/fisiopatologia , Animais , Disfunção Cognitiva/etiologia , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Privação do Sono/complicaçõesRESUMO
BACKGROUND: Craniosynostosis, defined as premature fusion of one or more cranial sutures, affects approximately 1 in every 2000-2500 live births. Sagittal craniosynostosis (CS), the most prevalent form of isolated craniosynostosis, is caused by interplay between genetic and perinatal environmental insults. However, the underlying details remain largely unknown. METHODS: The proband (a female monochorionic twin diagnosed with CS), her healthy co-twin sister and parents were enrolled. Obstetric history was extracted from medical records. Genetic screening was performed by whole exome sequencing (WES) and confirmed by Sanger sequencing. Functional annotation, conservation and structural analysis were predicted in public database. Phenotype data of Axin2 knockout mice was downloaded from The International Mouse Phenotyping Consortium (IMPC, http://www.mousephenotype.org ). RESULTS: Obstetric medical records showed that, except for the shared perinatal risk factors by the twins, the proband suffered additional persistent breech presentation and intrauterine growth restriction. We identified a heterozygous mutation of Axin2 (c.1181G > A, p.R394H, rs200899695) in monochorionic twins and their father, but not in the mother. This mutation is not reported in Asian population and results in replacement of Arg at residue 394 by His (p.R394H). Arg 394 is located at the GSK3ß binding domain of Axin2 protein, which is highly conserved across species. The mutation was predicted to be potentially deleterious by in silico analysis. Incomplete penetrance of Axin2 haploinsufficiency was found in female mice. CONCLUSIONS: Axin2 (c.1181G > A, p.R394H, rs200899695) mutation confers susceptibility and perinatal risk factors trigger the occurrence of sagittal craniosynostosis. Our findings provide a new evidence for the gene-environment interplay in understanding pathogenesis of craniosynostosis in Chinese population.
Assuntos
Proteína Axina/genética , Craniossinostoses/genética , Animais , Povo Asiático/genética , China , Feminino , Humanos , Camundongos , Camundongos Knockout , Mutação , Fatores de Risco , Gêmeos Monozigóticos , Sequenciamento do ExomaRESUMO
OBJECTIVES: To explore and establish the diagnosis, syndrome classification and syndrome differentiation criteria of palpitations below the heart in traditional Chinese medicine (TCM) in order to lay a foundation for the clinical diagnosis, treatment and research of palpitations below the heart. METHODS: In the early stage of this study, we searched the literature related to palpitations below the heart in TCM in domestic and foreign databases, analyzed the results and developed an expert consultation questionnaire. Using the Delphi method, a survey was conducted by 19 expert TCM practitioners. The survey results were statistically analyzed, aggregated and categorized to create the next round of questionnaires, and the process was repeated was repeated for a total of 4 rounds of expert opinions and until a consensus was achieved. Finally, the questionnaire items were classified into the main diagnosis (primary disease) and secondary diagnosis (secondary disease) for each syndrome. RESULTS: This study was completed ahead of schedule after 2 rounds of expert questionnaire surveys. A total of 19 exceptional TCM experts from all over China reached a consensus on 1 diagnostic standard and 4 syndrome types. The main diagnoses of palpitations below the heart included "conscious sub cardiac epigastric beating," "throbbing at the lower part of the heart" and "palpitation rhythm consistent with the pulse and obvious pulsation in the heart area," while the secondary diagnosis was "palpitation obvious after nervous tension, fatigue, drinking water or changing body position." Based on the balance of TCM Yin (negative, dark, feminine) and Yang (positive, bright, masculine) energy, TCM syndrome differentiation (Bian Zheng - the comprehensive analysis of clinical information obtained from the 4 main diagnostic TCM procedures: observation, listening, questioning, and pulse analysis, that is used to guide the choice of treatment by acupuncture and/or TCM) of palpitations below the heart are differentiated as heart yang deficiency syndrome, middle yang deficiency syndrome, kidney yang deficiency syndrome and phlegm drink syndrome, and the main and secondary syndromes of each are established. In the consultation process, the expert opinions were highly correlated, questionnaire reliability was strong and the results were credible. CONCLUSIONS: The criteria proposed in this study do not claim to be the best or the most accurate, but they do provide some guidelines for practitioners, a basis for clinical differentiation and treatment with TCM and a basis for further randomized controlled trials in the future. Further research is needed in order to reach a consensus regarding TCM treatment of palpitations below the heart.
Assuntos
Medicina Tradicional Chinesa , Consenso , Técnica Delphi , Humanos , Reprodutibilidade dos Testes , SíndromeRESUMO
Acinetobacter haemolyticus (A. haemolyticus) is a significant Acinetobacter pathogen, and the resistance of A. haemolyticus continues to rise due to abuse of antibiotics and the frequent gene exchange between bacteria in hospital. In this study, we performed complete genome sequencing of two A. haemolyticus strains TJR01 and TJS01 to improve our understanding of pathogenic and resistance of A. haemolyticus. Both TJR01 and TJS01 contain one chromosome and two plasmids. Compared to TJS01, more virulence factors (VFs) associated pathogenicity and resistant genes were predicted in TJR01 due to T4SS and integron associated with combination and transport. Antimicrobial susceptibility results were consistent with sequencing. We suppose TJS01 was a susceptive strain and TJR01 was an acquired multidrug resistance strain due to plasmid-mediated horizontal gene transfer. We hope these findings may be helpful for clinical treatment of A. haemolyticus infection and reduce the risk of potential outbreak infection.
Assuntos
Acinetobacter/genética , Genoma Bacteriano , Acinetobacter/isolamento & purificação , Acinetobacter/metabolismo , Acinetobacter/patogenicidade , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana , Genes Bacterianos , Genômica , Humanos , Anotação de Sequência Molecular , Filogenia , Infecções Respiratórias/microbiologia , Escarro/microbiologia , Fatores de Virulência/genéticaRESUMO
Congenital anomalies of the kidney and urinary tract (CAKUTs) are the most common cause of chronic kidney disease in children. Human 16p11.2 deletions have been associated with CAKUT, but the responsible molecular mechanism remains to be illuminated. To explore this, we investigated 102 carriers of 16p11.2 deletion from multi-center cohorts, among which we retrospectively ascertained kidney morphologic and functional data from 37 individuals (12 Chinese and 25 Caucasian/Hispanic). Significantly higher CAKUT rates were observed in 16p11.2 deletion carriers (about 25% in Chinese and 16% in Caucasian/Hispanic) than those found in the non-clinically ascertained general populations (about 1/1000 found at autopsy). Furthermore, we identified seven additional individuals with heterozygous loss-of-function variants in TBX6, a gene that maps to the 16p11.2 region. Four of these seven cases showed obvious CAKUT. To further investigate the role of TBX6 in kidney development, we engineered mice with mutated Tbx6 alleles. The Tbx6 heterozygous null (i.e., loss-of-function) mutant (Tbx6+/â) resulted in 13% solitary kidneys. Remarkably, this incidence increased to 29% in a compound heterozygous model (Tbx6mh/â) that reduced Tbx6 gene dosage to below haploinsufficiency, by combining the null allele with a novel mild hypomorphic allele (mh). Renal hypoplasia was also frequently observed in these Tbx6-mutated mouse models. Thus, our findings in patients and mice establish TBX6 as a novel gene involved in CAKUT and its gene dosage insufficiency as a potential driver for kidney defects observed in the 16p11.2 microdeletion syndrome.
Assuntos
Escoliose , Animais , Humanos , Rim , Camundongos , Estudos Retrospectivos , Proteínas com Domínio T/genética , Anormalidades Urogenitais , Refluxo VesicoureteralRESUMO
Galectin-3 (Gal-3) binds to cell adhesion glycoprotein CD146 to promote cytokine secretion and mediate endothelial cell migration. Here, we used Nuclear Magnetic Resonance (NMR) 15N-Heteronuclear Single Quantum Coherence (HSQC) spectroscopy to investigate binding between 15N-labeled Gal-3 and the extracellular domain (eFL) of purified CD146 (five Ig-like ectodomains D1-D5) and a shorter, D5-deleted version of CD146 (D1-D4). Binding of Gal-3 and its carbohydrate recognition domain (CRD) to CD146 D1-D4 is greatly reduced vis-à-vis CD146 eFL, supporting the proposal of a larger number of glycosylation sites on D5. Even though the canonical sugar-binding ß-sheet S-face (ß-strands 1, 10, 3, 4, 5, 6) of the Gal-3 ß-sandwich is involved in interactions with CD146 (e.g. N-linked glycosylation sites), equivalent HSQC spectral perturbations at residues on the opposing Gal-3 F-face ß-sheet (ß-strands 11, 2, 7, 8, 9) indicate involvement of the Gal-3 F-face in binding CD146. This is supported by the observation that addition of lactose, while significantly attenuating Gal-3 binding (primarily with the S-face) to CD146 eFL, does not abolish it. Bio-Layer Interferometry studies with Gal-3 F-face mutants yield KD values to demonstrate a significant decrease (L203A) or increase (V204A, L218A, T243A) in net binding to CD146 eFL compared to wild type Gal-3. However, HSQC lactose titrations show no highly significant effects on sugar binding to the Gal-3 CRD S-face. Overall, our findings indicate that Gal-3 binding to CD146 is more involved than simple interactions with ß-galactoside epitopes on the cell receptor, and that there is a direct role for the lectin's CRD F-face in the CD146 binding process.
Assuntos
Antígeno CD146/metabolismo , Galectina 3/química , Sítios de Ligação , Galectina 3/genética , Galectina 3/metabolismo , Células HEK293 , Humanos , Lactose/análogos & derivados , Mutação , Ligação ProteicaRESUMO
Congenital anomalies of the kidney and urinary tract (CAKUT) are a wide range of congenital structural renal defects. CAKUT is the leading cause of chronic renal failure and end-stage renal disease in children. Studies in humans and animal models have confirmed the large genetic contribution to CAKUT. The previous evidence suggested that human TBX6 coding mutations might cause CAKUT via gene-dosage insufficiency. However, the potential involvement of TBX6 noncoding mutations in CAKUT remains to be elucidated. Here, we described DNA sequencing and copy-number analysis of TBX6 in 269 Chinese subjects with CAKUT. Interestingly, we identified two heterozygous noncoding variants of TBX6 in sporadic subjects with CAKUT: one is c.769-7delT, from a subject with duplex renal and collecting system, and the other is a 3' untranslated region (3'-UTR) variant (c.1392C>T) from a subject with unilateral renal hypoplasia. These two TBX6 noncoding variants are novel and extremely rare, respectively, in human populations archived in the ExAC database. The mini-gene splicing assay showed that the TBX6 c.769-7delT variant significantly reduced the splicing efficiency of TBX6 intron 5 when compared to the wild-type control. In this work, we identified a novel splicing variant of TBX6 in human CAKUT. Our experimental observations suggested that the TBX6 noncoding variant can affect gene expression and may potentially be involved in human CAKUT.
Assuntos
Sítios de Splice de RNA/genética , Análise de Sequência de DNA , Proteínas com Domínio T/genética , Anormalidades Urogenitais/genética , Refluxo Vesicoureteral/genética , Adolescente , Criança , Feminino , Humanos , Rim/fisiopatologia , Masculino , Mutação , Fenótipo , Anormalidades Urogenitais/fisiopatologia , Refluxo Vesicoureteral/fisiopatologia , Sequenciamento do ExomaRESUMO
Even though a vaccine that targets tumor-associated carbohydrate antigens on epithelial carcinoma cells presents an attractive therapeutic approach, relatively poor immunogenicity limits its development. In this study, we investigated the immunological activity of a fluoro-substituted Sialyl-Tn (F-STn) analogue coupled to the non-toxic cross-reactive material of diphtheria toxin197 (CRM197). Our results indicate that F-STn-CRM197 promotes a greater immunogenicity than non-fluorinated STn-CRM197. In the presence or absence of adjuvant, F-STn-CRM197 remarkably enhances both cellular and humoral immunity against STn by increasing antigen-specific lymphocyte proliferation and inducing a mixed Th1/Th2 response leading to production of IFN-γ and IL-4 cytokines, as well as STn-specific antibodies. Furthermore, antisera produced from F-STn-CRM197 immunization significantly recognizes STn-positive tumor cells and increases cancer cell lysis induced by antibody-dependent cell-mediated cytotoxicity (ADCC) or complement-dependent cytotoxicity (CDC) pathways. Our data suggest that this F-STn vaccine may be useful for cancer immunotherapy and possibly for prophylactic prevention of cancer.
Assuntos
Anticorpos Antineoplásicos/farmacologia , Antígenos Glicosídicos Associados a Tumores/química , Proteínas de Bactérias/farmacologia , Vacinas Anticâncer/farmacologia , Neoplasias do Colo/terapia , Glicoconjugados/farmacologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos Antineoplásicos/isolamento & purificação , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Antígenos Glicosídicos Associados a Tumores/imunologia , Proteínas de Bactérias/química , Proteínas de Bactérias/imunologia , Vacinas Anticâncer/síntese química , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Feminino , Expressão Gênica , Glicoconjugados/síntese química , Glicoconjugados/imunologia , Halogenação , Humanos , Soros Imunes/química , Soros Imunes/farmacologia , Imunidade Celular/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Imunização , Imunogenicidade da Vacina , Interferon gama/genética , Interferon gama/imunologia , Interleucina-4/genética , Interleucina-4/imunologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Baço/efeitos dos fármacos , Baço/imunologia , Equilíbrio Th1-Th2RESUMO
Isomaltose-oligosaccharides (IMOs), as food ingredients with prebiotic functionality, can be prepared via enzymatic synthesis using α-glucosidase. In the present study, the α-glucosidase (GSJ) from Geobacillus sp. strain HTA-462 was cloned and expressed in Escherichia coli BL21 (DE3). Recombinant GSJ was purified and biochemically characterized. The optimum temperature condition of the recombinant enzyme was 65 °C, and the half-life was 84 h at 60 °C, whereas the enzyme was active over the range of pH 6.0-10.0 with maximal activity at pH 7.0. The α-glucosidase activity in shake flasks reached 107.9 U/mL and using 4-Nitrophenyl ß-D-glucopyranoside (pNPG) as substrate, the Km and Vmax values were 2.321 mM and 306.3 U/mg, respectively. The divalent ions Mn2+ and Ca2+ could improve GSJ activity by 32.1% and 13.8%. Moreover, the hydrolysis ability of recombinant α-glucosidase was almost the same as that of the commercial α-glucosidase (Bacillus stearothermophilus). In terms of the transglycosylation reaction, with 30% maltose syrup under the condition of 60 °C and pH 7.0, IMOs were synthesized with a conversion rate of 37%. These studies lay the basis for the industrial application of recombinant α-glucosidase.
Assuntos
Proteínas de Bactérias/química , Escherichia coli/metabolismo , Geobacillus/genética , Isomaltose/química , alfa-Glucosidases/química , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Clonagem Molecular , Estabilidade Enzimática , Escherichia coli/genética , Geobacillus/enzimologia , Oligossacarídeos/síntese química , Oligossacarídeos/química , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Especificidade por Substrato , alfa-Glucosidases/biossíntese , alfa-Glucosidases/genéticaRESUMO
BACKGROUND: Intraoperative remifentanil anesthesia exaggerates postoperative pain sensitivity. Recent studies recapitulate the significance of protein kinase Mζ in α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-mediated pathologic pain. Kalirin-7, a Rho guanine nucleotide exchange factor, coordinates AMPA receptor trafficking and dendritic spine plasticity. This study examines whether protein kinase Mζ and Kalirin-7 contribute to remifentanil-induced postincisional hyperalgesia via AMPA receptor. METHODS: Plantar incision was performed 10 min after the start of remifentanil infusion (1 µg · kg · min for 60 min). Paw withdrawal threshold (primary outcome), spinal protein kinase Mζ activity, Kalirin-7 expression, AMPA receptor trafficking, and spine morphology were assessed. Protein kinase Mζ inhibitor and Kalirin-7 knockdown by short hairpin RNA elucidated the mechanism and prevention of hyperalgesia. Whole-cell patch-clamp recording analyzed the role of protein kinase Mζ in spinal AMPA receptor-induced current. RESULTS: Remifentanil reduced postincisional paw withdrawal threshold (mean ± SD, control vs. hyperalgesia, 18.9 ± 1.6 vs. 5.3 ± 1.2 g, n = 7) at postoperative 48 h, which was accompanied by an increase in spinal protein kinase Mζ phosphorylation (97.8 ± 25.1 vs. 181.5 ± 18.3%, n = 4), Kalirin-7 production (101.9 ± 29.1 vs. 371.2 ± 59.1%, n = 4), and number of spines/10 µm (2.0 ± 0.3 vs. 13.0 ± 1.6, n = 4). Protein kinase Mζ inhibitor reduced remifentanil-induced hyperalgesia, Kalirin-7 expression, and GluA1 trafficking. Incubation with protein kinase Mζ inhibitor reversed remifentanil-enhanced AMPA receptor-induced current in dorsal horn neurons. Kalirin-7 deficiency impaired remifentanil-caused hyperalgesia, postsynaptic GluA1 insertion, and spine plasticity. Selective GluA2-lacking AMPA receptor antagonist prevented hyperalgesia in a dose-dependent manner. CONCLUSIONS: Spinal protein kinase Mζ regulation of GluA1-containing AMPA receptor trafficking and spine morphology via Kalirin-7 overexpression is a fundamental pathogenesis of remifentanil-induced hyperalgesia in rats.
Assuntos
Espinhas Dendríticas/metabolismo , Fatores de Troca do Nucleotídeo Guanina/biossíntese , Hiperalgesia/metabolismo , Dor Pós-Operatória/metabolismo , Proteína Quinase C/fisiologia , Receptores de AMPA/metabolismo , Remifentanil/toxicidade , Analgésicos Opioides/toxicidade , Animais , Espinhas Dendríticas/efeitos dos fármacos , Hiperalgesia/induzido quimicamente , Masculino , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Técnicas de Cultura de Órgãos , Dor Pós-Operatória/induzido quimicamente , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/fisiologia , Ratos , Ratos Sprague-Dawley , Ferida Cirúrgica/complicações , Ferida Cirúrgica/metabolismoRESUMO
The gonad of jellyfish (RhopilemaesculentumKishinouye), containing high protein content with a rich amino acid composition, is suitable for the preparation of bioactive peptides. Jellyfish gonad was hydrolysed with neutral protease to obtain jellyfish gonad protein hydrolysate (JGPH), which was then purified sequentially by ultrafiltration, gel filtration chromatography, and RP-HPLC. The peptides were characterized with HPLC-MS/MS. One peptide with amino acid sequence Ser-Tyr (SY) was identified and synthesized, which showed good ACE inhibitory and antioxidant activity. The IC50 of this peptide on DPPH, ·OH, super oxygen anion scavenging activities, and ACE inhibitory activity are 84.623 µM, 1177.632 µM, 456.663 µM, and 1164.179 µM, respectively. The anchor in the binding site of SY and ACE C-domain (ACE-C) was obtained by molecular simulations. The results showed that the dipeptide purified from jellyfish gonad protein hydrolysates can be used as functional food material and is helpful in the study of antioxidant and inhibition of ACE.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/química , Dipeptídeos/química , Sequestradores de Radicais Livres/química , Sequência de Aminoácidos , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Animais , Compostos de Bifenilo/química , Domínio Catalítico , Cromatografia em Gel , Dipeptídeos/isolamento & purificação , Sequestradores de Radicais Livres/isolamento & purificação , Gônadas/química , Hidrólise , Simulação de Acoplamento Molecular , Peptidil Dipeptidase A/química , Picratos/química , Ligação Proteica , Cifozoários/química , Superóxidos/químicaRESUMO
Since the immunosuppressive agents currently used in clinics have significant side effects, it is very important to search for new effective and safe immunosuppressants. Iminosugars as a new class of immunosuppressants are less explored. In this report, 24 new N-arylated iminosugar derivatives, including d-talo and d-galacto epimers, were designed and synthesized, and their immunosuppressive effects were evaluated by MTT assay. The experimental data demonstrated that compound 20 showed the strongest inhibition effect (IC50 = 6.94 µM). Further studies revealed that the inhibitory effects on splenocyte proliferation may come from the suppression of both IFN-γ and IL-4 cytokines. The preliminary structure-activity relationship (SAR) analysis suggested that N-arylated d-galacto-type iminosugars showed better inhibitory activities than d-talo-type analogues. The SAR analysis also showed that the inhibition effect of iminosugars can be improved by decreasing the polarity or increasing the hydrophobicity. These results may be beneficial to the discovery of new iminosugar derivatives as immunosuppressive agents.
Assuntos
Imino Açúcares/farmacologia , Imunossupressores/farmacologia , Lactamas/farmacologia , Baço/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Imino Açúcares/síntese química , Imino Açúcares/química , Imunossupressores/síntese química , Imunossupressores/química , Células Jurkat , Lactamas/síntese química , Lactamas/química , Camundongos , Conformação Molecular , Relação Estrutura-AtividadeRESUMO
Correction for 'Synthesis and immunological evaluation of MUC1 glycopeptide conjugates bearing N-acetyl modified STn derivatives as anticancer vaccines' by An Xiao et al., Org. Biomol. Chem., 2016, 14, 7226-7237.
RESUMO
Glycoprotein MUC1 is an attractive target for anti-tumor vaccine development. However, the weak immunogenicity of MUC1 remains a significant problem. To solve this problem, several STn derivatives with N-acetyl modifications were synthesized and incorporated into a 20-amino acid MUC1 tandem repeat sequence. The modified STn-MUC1 glycopeptides were further connected to a carrier protein keyhole limpet hemocyanin (KLH). The immunological effects of these synthetic vaccine conjugates were evaluated using the BALB/c mouse model. The results showed that vaccine V2 elicited higher titers of antibodies which cross-reacted with the native STn-MUC1 antigen. Moreover, the elicited antisera reacted with the STn-MUC1 antigen-positive tumor cells, indicating that the carbohydrate antigen modification strategy may hold potential to overcome the weak immunogenicity of natural MUC1 glycopeptides.
Assuntos
Antígenos Glicosídicos Associados a Tumores/imunologia , Glicopeptídeos/síntese química , Glicopeptídeos/farmacologia , Hemocianinas/síntese química , Hemocianinas/farmacologia , Animais , Antígenos Glicosídicos Associados a Tumores/metabolismo , Vacinas Anticâncer/farmacologia , Linhagem Celular Tumoral , Feminino , Glicopeptídeos/imunologia , Hemocianinas/imunologia , Humanos , Soros Imunes/química , Soros Imunes/imunologia , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Mucina-1/química , Neoplasias/prevenção & controleRESUMO
Tumor-associated carbohydrate antigens (TACAs), which are aberrantly expressed on the surface of tumor cells, are important targets for anticancer vaccine development. Herein, several N-acyl modified Tn analogues were synthesized and conjugated with carrier protein CRM197. The immunological results of these glycoconjugates indicated that 6-CRM197 elicited higher titers of antibodies which cross-reacted with native Tn antigen than the unmodified 2-CRM197 did. The IFN-γ-producing frequency of lymphocytes in mice treated with 6-CRM197 was obviously increased, compared to that of mice vaccinated with 2-CRM197 (p=0.016), which was typically associated with the Th1 response. Moreover, the elicited antisera against antigen 6-CRM197 reacted strongly with the Tn-positive tumor cells, implying the potential of this glycoconjugate as an anticancer vaccine.