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1.
J Genet ; 1032024.
Artigo em Inglês | MEDLINE | ID: mdl-38736250

RESUMO

In acute lymphoblastic leukaemia (ALL), elevated foetal haemoglobin (HbF) levels have been associated with the prognosis of patients. Genetic variants in HbF regulatory genes: BAF chromatin remodelling complex subunit (BCL11A), HBS1L-MYB transcriptional GTPase intergenic region (HBS1L-MYB), Krüppel-like factor 1 (KLF1), haemoglobin gamma subunit 2 (HBG2), haemoglobin gamma subunit 1 (HBG1), and haemoglobin subunit beta pseudogene 1 (HBBP1) are often associatedwith elevatedHbF concentration. This study investigated the association of genetic variants in HbF regulatory genes with HbF concentration, unfavourable prognosis, and outcome in children with ALL.We quantified HbF concentration and genotyped 17 genetic variants in 48 patients with ALL and 64 children without ALL as a reference group. HbF concentrationwas higher in patients than in the reference group (4.4%vs 1.4%), and 75%(n = 36) of thepatientshadHbF>2.5%.Unfavourable prognosis ALL was established in 68.8% (n = 33) of the patients. Variant HBG2 rs7482144 was associated with high HbF concentration (P = 0.015); while HBS1L-MYB rs9399137 (P = 0.001), HBG2 rs7482144 (P = 0.001) and the ß-globin genes HBG2, HBG1, and HBPP1 haplotypeTGC(P = 0.017) with unfavourable prognosisALL.Additionally, variantBCL11A rs4671393 showed a protective role (P = 0.0001). In conclusion, variants HBG2 rs7482144, HBS1L-MYB rs9399137 and BCL11A rs4671393 may play a significant role in ALL.


Assuntos
Hemoglobina Fetal , Polimorfismo de Nucleotídeo Único , Leucemia-Linfoma Linfoblástico de Células Precursoras , Proteínas Repressoras , Humanos , Hemoglobina Fetal/genética , Feminino , Masculino , Criança , Prognóstico , Proteínas Repressoras/genética , Pré-Escolar , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Lactente , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas c-myb/genética , Proteínas de Transporte/genética , Adolescente , Genótipo , gama-Globinas/genética , Proteínas de Ligação ao GTP
2.
J Mol Biol ; 436(10): 168569, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38604527

RESUMO

Transglutaminase 2 (TG2) performs many functions both under physiological and pathological conditions. In cancer, its expression is associated with aggressiveness, propensity to epithelial-mesenchymal transition, and metastasis. Since TG2 performs key functions both outside and inside the cell, using inhibitors with different membrane permeability we analyzed the changes in the transcriptome induced in two triple-negative cell lines (MDA-MB-436 and MDA-MB-231) with aggressive features. By characterizing pathways and gene networks, we were able to define the effects of TG2 inhibitors (AA9, membrane-permeable, and NCEG2, impermeable) in relation to the roles of the enzyme in the intra- and extracellular space within the context of breast cancer. The deregulated genes revealed p53 and integrin signaling to be the common pathways with some genes showing opposite changes in expression. In MDA-MB-436, AA9 induced apoptosis, modulated cadherin, Wnt, gastrin and cholecystokinin receptors (CCKR) mediated signaling, with RHOB and GNG2 playing significant roles, and affected the Warburg effect by decreasing glycolytic enzymes. In MDA-MB-231 cells, AA9 strongly impacted HIF-mediated hypoxia, including AKT and mTOR pathway. These effects suggest an anti-tumor activity by blocking intracellular TG2 functions. Conversely, the use of NCEG2 stimulated the expression of ATP synthase and proteins involved in DNA replication, indicating a potential promotion of cell proliferation through inhibition of extracellular TG2. To effectively utilize these molecules as an anti-tumor strategy, an appropriate delivery system should be evaluated to target specific functions and avoid adverse effects. Additionally, considering combinations with other pathway modulators is crucial.


Assuntos
Proteínas de Ligação ao GTP , Proteína 2 Glutamina gama-Glutamiltransferase , Transglutaminases , Humanos , Transglutaminases/metabolismo , Transglutaminases/genética , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Transcriptoma/efeitos dos fármacos , Perfilação da Expressão Gênica , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo
3.
Exp Lung Res ; 50(1): 106-117, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38642025

RESUMO

BACKGROUND: Pulmonary emphysema is a condition that causes damage to the lung tissue over time. GBP5, as part of the guanylate-binding protein family, is dysregulated in mouse pulmonary emphysema. However, the role of GBP5 in lung inflammation in ARDS remains unveiled. METHODS: To investigate whether GBP5 regulates lung inflammation and autophagy regulation, the study employed a mouse ARDS model and MLE-12 cell culture. Vector transfection was performed for the genetic manipulation of GBP5. Then, RT-qPCR, WB and IHC staining were conducted to assess its transcriptional and expression levels. Histological features of the lung tissue were observed through HE staining. Moreover, ELISA was conducted to evaluate the secretion of inflammatory cytokines, autophagy was assessed by immunofluorescent staining, and MPO activity was determined using a commercial kit. RESULTS: Our study revealed that GBP5 expression was altered in mouse ARDS and LPS-induced MLE-12 cell models. Moreover, the suppression of GBP5 reduced lung inflammation induced by LPS in mice. Conversely, overexpression of GBP5 diminished the inhibitory impact of LPS on ARDS during autophagy, leading to increased inflammation. In the cell line of MLE-12, GBP5 exacerbates LPS-induced inflammation by blocking autophagy. CONCLUSION: The study suggests that GBP5 facilitates lung inflammation and autophagy regulation. Thus, GBP5 could be a potential therapeutic approach for improving ARDS treatment outcomes, but further research is required to validate these findings.


Assuntos
Autofagia , Proteínas de Ligação ao GTP , Lesão Pulmonar , Pneumonia , Síndrome do Desconforto Respiratório , Animais , Camundongos , Autofagia/efeitos dos fármacos , Inflamação/metabolismo , Lipopolissacarídeos , Pulmão/metabolismo , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/metabolismo , Pneumonia/metabolismo , Enfisema Pulmonar , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/metabolismo , Proteínas de Ligação ao GTP/antagonistas & inibidores , Proteínas de Ligação ao GTP/metabolismo
4.
Cells ; 13(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38667282

RESUMO

Transglutaminase type 2 (TG2) is the most ubiquitously expressed member of the transglutaminase family. TG2 catalyzes the transamidation reaction leading to several protein post-translational modifications and it is also implicated in signal transduction thanks to its GTP binding/hydrolyzing activity. In the nervous system, TG2 regulates multiple physiological processes, such as development, neuronal cell death and differentiation, and synaptic plasticity. Given its different enzymatic activities, aberrant expression or activity of TG2 can contribute to tumorigenesis, including in peripheral and central nervous system tumors. Indeed, TG2 dysregulation has been reported in meningiomas, medulloblastomas, neuroblastomas, glioblastomas, and other adult-type diffuse gliomas. The aim of this review is to provide an overview of the biological and functional relevance of TG2 in the pathogenesis of nervous system tumors, highlighting its involvement in survival, tumor inflammation, differentiation, and in the resistance to standard therapies.


Assuntos
Proteínas de Ligação ao GTP , Neoplasias do Sistema Nervoso , Proteína 2 Glutamina gama-Glutamiltransferase , Transglutaminases , Humanos , Transglutaminases/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Neoplasias do Sistema Nervoso/patologia , Neoplasias do Sistema Nervoso/enzimologia , Neoplasias do Sistema Nervoso/metabolismo , Animais
5.
Vet Microbiol ; 293: 110089, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38678845

RESUMO

Brucellosis is a zoonotic disease that affects wild and domestic animals. It is caused by members of the bacterial genus Brucella. Guanylate-binding protein 1 (GBP1) is associated with microbial infections. However, the role of GBP1 during Brucella infection remains unclear. This investigation aimed to identify the association of GBP1 with brucellosis. Results showed that Brucella infection induced GBP1 upregulation in RAW 264.7 murine macrophages. Small interfering GBP1 targeting RNAs were utilized to explore how GBP1 regulates the survival of Brucella intracellularly. Results revealed that GBP1 knockdown promoted Brucella's survival ability, activated Nod-like receptor (NLR) containing a pyrin domain 3 (NLRP3) and absent in melanoma 2 (AIM2) inflammatory corpuscles, and induced pro-inflammatory cytokines IFN-γ and IL-1ß. Furthermore, Brucella stimulated the expression of GBP1 in bone marrow-derived macrophages (BMDMs) and mice. During the inhibition of GBP1 in BMDMs, the intracellular growth of Brucella increased. In comparison, GBP1 downregulation enhanced the accumulation of Brucella-induced reactive oxygen species (ROS) in macrophages. Overall, the data indicate a significant role of GBP1 in regulating brucellosis and suggest the function underlying its suppressive effect on the survival and growth of Brucella intracellularly.


Assuntos
Brucelose , Proteínas de Ligação ao GTP , Macrófagos , Animais , Camundongos , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Macrófagos/microbiologia , Brucelose/microbiologia , Células RAW 264.7 , Brucella/genética , Espécies Reativas de Oxigênio/metabolismo , Camundongos Endogâmicos C57BL
6.
Front Immunol ; 15: 1371706, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650935

RESUMO

Pulmonary hypertension (PH) pathogenesis is driven by inflammatory and metabolic derangements as well as glycolytic reprogramming. Induction of both interleukin 6 (IL6) and transglutaminase 2 (TG2) expression participates in human and experimental cardiovascular diseases. However, little is known about the role of TG2 in these pathologic processes. The current study aimed to investigate the molecular interactions between TG2 and IL6 in mediation of tissue remodeling in PH. A lung-specific IL6 over-expressing transgenic mouse strain showed elevated right ventricular (RV) systolic pressure as well as increased wet and dry tissue weights and tissue fibrosis in both lungs and RVs compared to age-matched wild-type littermates. In addition, IL6 over-expression induced the glycolytic and fibrogenic markers, hypoxia-inducible factor 1α, pyruvate kinase M2 (PKM2), and TG2. Consistent with these findings, IL6 induced the expression of both glycolytic and pro-fibrogenic markers in cultured lung fibroblasts. IL6 also induced TG2 activation and the accumulation of TG2 in the extracellular matrix. Pharmacologic inhibition of the glycolytic enzyme, PKM2 significantly attenuated IL6-induced TG2 activity and fibrogenesis. Thus, we conclude that IL6-induced TG2 activity and cardiopulmonary remodeling associated with tissue fibrosis are under regulatory control of the glycolytic enzyme, PKM2.


Assuntos
Fibroblastos , Proteínas de Ligação ao GTP , Hipertensão Pulmonar , Interleucina-6 , Pulmão , Camundongos Transgênicos , Proteína 2 Glutamina gama-Glutamiltransferase , Piruvato Quinase , Transglutaminases , Animais , Humanos , Camundongos , Modelos Animais de Doenças , Fibroblastos/metabolismo , Fibrose , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/genética , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/etiologia , Interleucina-6/metabolismo , Pulmão/patologia , Pulmão/imunologia , Pulmão/metabolismo , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Piruvato Quinase/metabolismo , Piruvato Quinase/genética , Transglutaminases/metabolismo , Transglutaminases/genética
7.
Actas Esp Psiquiatr ; 52(2): 83-98, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38622006

RESUMO

BACKGROUND: Vascular dementia (VaD) is a prevalent neurodegenerative disease characterized by cognitive impairment due to cerebrovascular factors, affecting a significant portion of the aging population and highlighting the critical need to understand specific targets and mechanisms for effective prevention and treatment strategies. We aimed to identify pathways and crucial genes involved in the progression of VaD through bioinformatics analysis and subsequently validate these findings. METHODS: We conducted differential expression analysis, Weighted Gene Co-expression Network Analysis (WGCNA), Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, and Protein-Protein Interaction (PPI) analysis. We utilized pheochromocytoma 12 (PC12) cells to create an in vitro oxygen-glucose deprivation (OGD) model. We investigated the impact of overexpression and interference of adrenoceptor alpha 1D (ADRA1D) on OGD PC12 cells using TdT-mediated dUTP nick-end labeling (TUNEL), reverse transcription-quantitative polymerase chain reaction (RT-qPCR), western blot (WB), and Fluo-3-pentaacetoxymethyl ester (Fluo-3 AM) analysis. RESULTS: We found 187 differentially expressed genes (DEGs) in the red module that were strongly associated with VaD and were primarily enriched in vasoconstriction, G protein-coupled amine receptor activity, and neuroactive ligand-receptor interaction, mitogen-activated protein kinase (MAPK) signaling pathway, and cell adhesion. Among these pathways, we identified ADRA1D as a gene shared by vasoconstriction, G protein-coupled amine receptor activity, and neuroactive ligand-receptor interaction. The TUNEL assay revealed a significant decrease in PC12 cell apoptosis with ADRA1D overexpression (p < 0.01) and a significant increase in apoptosis upon silencing ADRA1D (p < 0.01). RT-qPCR and WB analysis revealed elevated ADRA1D expression (p < 0.001) and decreased phospholipase C beta (PLCß) and inositol 1,4,5-trisphosphate receptor (IP3R) expression (p < 0.05) with ADRA1D overexpression. Moreover, the Fluo-3 AM assessment indicated significantly lower intracellular Ca2+ levels with ADRA1D overexpression (p < 0.001). Conversely, interference with ADRA1D yielded opposite results. CONCLUSION: Our study provides a new perspective on the pathogenic mechanisms of VaD and potential avenues for therapeutic intervention. The results highlight the role of ADRA1D in modulating cellular responses to OGD and VaD, suggesting its potential as a target for VaD treatment.


Assuntos
Compostos de Anilina , Demência Vascular , Doenças Neurodegenerativas , Xantenos , Animais , Ratos , Humanos , Idoso , Demência Vascular/genética , Ligantes , Aminas , Transdução de Sinais/genética , Proteínas de Ligação ao GTP
8.
BMC Womens Health ; 24(1): 240, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622605

RESUMO

BACKGROUND: Human papillomavirus (HPV) infection is an important factor leading to cervical cell abnormalities. 90% of cervical cancers are closely associated with persistent infection of high-risk HPV, with the highest correlation with HPV16 and 18. Currently available vaccines and antivirals have limited effectiveness and coverage. Guanylate binding protein 1 (GBP1) was induced by interferon gamma and involved in many important cellular processes such as clearance of various microbial pathogens. However, whether GBP1 can inhibit human papillomavirus infection is unclear. RESULTS: In this study, we found that GBP1 can effectively degrade HPV18 E6, possibly through its GTPase activity or other pathways, and E6 protein degrades GBP1 through the ubiquitin-proteasome pathway to achieve immune escape. CONCLUSION: Therefore, GBP1 is an effector of IFN-γ anti-HPV activity. Our findings provided new insights into the treatment of HPV 18 infections.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Proteínas de Ligação ao GTP , Papillomavirus Humano 18 , Interferon gama/farmacologia
9.
Technol Cancer Res Treat ; 23: 15330338241241935, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38564315

RESUMO

Hepatocellular carcinoma (HCC), partly because of its complexity and high heterogeneity, has a poor prognosis and an extremely high mortality rate. In this study, mRNA sequencing expression profiles and relevant clinical data of HCC patients were gathered from different public databases. Kaplan-Meier survival curves as well as ROC curves validated that OLA1|CLEC3B was an independent predictor with better predictive capability of HCC prognosis compared to OLA1 and CLEC3B separately. Further, the cell transfection experiment verified that knockdown of OLA1 inhibited cell proliferation, facilitated apoptosis, and improved sensitivity of HCC cells to gemcitabine. In this study, the prognostic model of HCC composed of OLA1/CLEC3B genes was constructed and verified, and the prediction ability was favorable. A higher level of OLA1 along with a lower level of CEC3B is a sign of poor prognosis in HCC. We revealed a novel gene pair OLA1|CLEC3B overexpressed in HCC patients, which may serve as a promising independent predictor of HCC survival and an approach for innovative diagnostic and therapeutic strategies.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Prognóstico , Neoplasias Hepáticas/genética , Apoptose/genética , Proliferação de Células/genética , Adenosina Trifosfatases , Proteínas de Ligação ao GTP
10.
Biomolecules ; 14(4)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38672511

RESUMO

TG2 is a unique member of the transglutaminase family as it undergoes a dramatic conformational change, allowing its mutually exclusive function as either a cross-linking enzyme or a G-protein. The enzyme's dysregulated activity has been implicated in a variety of pathologies (e.g., celiac disease, fibrosis, cancer), leading to the development of a wide range of inhibitors. Our group has primarily focused on the development of peptidomimetic targeted covalent inhibitors, the nature and size of which were thought to be important features to abolish TG2's conformational dynamism and ultimately inhibit both its activities. However, we recently demonstrated that the enzyme was unable to bind guanosine triphosphate (GTP) when catalytically inactivated by small molecule inhibitors. In this study, we designed a library of models targeting covalent inhibitors of progressively smaller sizes (15 to 4 atoms in length). We evaluated their ability to inactivate TG2 by measuring their respective kinetic parameters kinact and KI. Their impact on the enzyme's ability to bind GTP was then evaluated and subsequently correlated to the conformational state of the enzyme, as determined via native PAGE and capillary electrophoresis. All irreversible inhibitors evaluated herein locked TG2 in its open conformation and precluded GTP binding. Therefore, we conclude that steric bulk and structural complexity are not necessary factors to consider when designing TG2 inhibitors to abolish G-protein activity.


Assuntos
Alquilantes , Domínio Catalítico , Proteínas de Ligação ao GTP , Proteína 2 Glutamina gama-Glutamiltransferase , Transglutaminases , Transglutaminases/química , Transglutaminases/metabolismo , Transglutaminases/antagonistas & inibidores , Proteínas de Ligação ao GTP/química , Proteínas de Ligação ao GTP/metabolismo , Humanos , Alquilantes/química , Alquilantes/farmacologia , Guanosina Trifosfato/química , Guanosina Trifosfato/metabolismo , Compostos de Sulfidrila/química , Compostos de Sulfidrila/farmacologia , Conformação Proteica , Cinética , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia
11.
Cell Rep ; 43(4): 114045, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38578826

RESUMO

Autoantibodies against the enzyme transglutaminase 2 (TG2) are characteristic of celiac disease (CeD), and TG2-specific immunoglobulin (Ig) A plasma cells are abundant in gut biopsies of patients. Here, we describe the corresponding population of autoreactive B cells in blood. Circulating TG2-specific IgA cells are present in untreated patients on a gluten-containing diet but not in controls. They are clonally related to TG2-specific small intestinal plasma cells, and they express gut-homing molecules, indicating that they are plasma cell precursors. Unlike other IgA-switched cells, the TG2-specific cells are negative for CD27, placing them in the double-negative (IgD-CD27-) category. They have a plasmablast or activated memory B cell phenotype, and they harbor fewer variable region mutations than other IgA cells. Based on their similarity to naive B cells, we propose that autoreactive IgA cells in CeD are generated mainly through chronic recruitment of naive B cells via an extrafollicular response involving gluten-specific CD4+ T cells.


Assuntos
Linfócitos B , Doença Celíaca , Proteínas de Ligação ao GTP , Imunoglobulina A , Plasmócitos , Proteína 2 Glutamina gama-Glutamiltransferase , Transglutaminases , Doença Celíaca/imunologia , Doença Celíaca/patologia , Humanos , Transglutaminases/imunologia , Transglutaminases/metabolismo , Imunoglobulina A/imunologia , Imunoglobulina A/metabolismo , Imunoglobulina A/sangue , Linfócitos B/imunologia , Linfócitos B/metabolismo , Plasmócitos/imunologia , Plasmócitos/metabolismo , Proteínas de Ligação ao GTP/imunologia , Proteínas de Ligação ao GTP/metabolismo , Autoanticorpos/imunologia , Autoanticorpos/sangue , Adulto , Masculino , Feminino , Pessoa de Meia-Idade , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Glutens/imunologia
12.
Nat Commun ; 15(1): 2900, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575575

RESUMO

Currently, only Palivizumab and Nirsevimab that target the respiratory syncytical virus (RSV) fusion protein are licensed for pre-treatment of infants. Glycoprotein-targeting antibodies may also provide protection against RSV. In this study, we generate monoclonal antibodies from mice immunized with G proteins from RSV-A2 and RSV-B1 strains. These monoclonal antibodies recognize six unique antigenic classes (G0-G5). None of the anti-G monoclonal antibodies neutralize RSV-A2 or RSV-B1 in vitro. In mice challenged with either RSV-A2 line 19 F or RSV-B1, one day after treatment with anti-G monoclonal antibodies, all monoclonal antibodies reduce lung pathology and significantly reduce lung infectious viral titers by more than 2 logs on day 5 post-RSV challenge. RSV dissemination in the lungs was variable and correlated with lung pathology. We demonstrate new cross-protective anti-G monoclonal antibodies targeting multiple sites including conformation-dependent class G0 MAb 77D2, CCD-specific class G1 MAb 40D8, and carboxy terminus of CCD class G5 MAb 7H11, to support development of G-targeting monoclonal antibodies against RSV.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano , Humanos , Camundongos , Animais , Anticorpos Monoclonais , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Anticorpos Antivirais , Proteínas Virais de Fusão , Proteínas de Ligação ao GTP , Anticorpos Neutralizantes
13.
Methods Mol Biol ; 2754: 33-54, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512659

RESUMO

Alzheimer's disease, a progressive neurological disorder, is characterized by the accumulation of neurofibrillary tangles and senile plaques by Tau and amyloid-ß, respectively, in the brain microenvironment. The misfolded protein aggregates interact with several components of neuronal and glial cells such as membrane lipids, receptors, transporters, enzymes, cytoskeletal proteins, etc. Under pathological conditions, Tau interacts with several G-protein-coupled receptors (GPCRs), which undergoes either receptor signaling or desensitization followed by internalization of the protein complex. The purinergic GPCR, P2Y12 which is expressed in microglial cells, plays a key role in its activation and migration. Microglial cells sense and migrate to the site of injury aided by P2Y12 receptor that interacts with ADP released from damaged cells. P2Y12 receptor also interacts with misfolded Tau accumulated at the extracellular space and promotes receptor-mediated internalization. Immunocolocalization and co-immunoprecipitation studies demonstrated the interaction of Tau species with the P2Y12 receptor. Later, in-silico analyses were carried out with the repeat domain of Tau (TauRD), which has been identified as the interacting partner of P2Y12 receptor by in-vitro studies. Molecular docking and molecular dynamics simulation studies show the stability and the type of interaction in TauRD-receptor complex. Tau interaction with P2Y12 receptor plays a significant role in maintaining the active state of microglia which could lead to neuroinflammation and neuronal damage in AD brain. Hence, blocking P2Y12-Tau interaction and P2Y12-mediated Tau internalization in microglial cells could be possible therapeutic strategies in downregulating the severity of neuroinflammation in AD.


Assuntos
Doença de Alzheimer , Simulação de Dinâmica Molecular , Humanos , Simulação de Acoplamento Molecular , Receptores Purinérgicos P2Y12/metabolismo , Antagonistas do Receptor Purinérgico P2Y , Doenças Neuroinflamatórias , Doença de Alzheimer/metabolismo , Microglia/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Proteínas tau/metabolismo
14.
Clin Chim Acta ; 557: 117891, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38555049

RESUMO

BACKGROUND: Laboratory testing for celiac disease in pediatric patients integrates serology, genetic susceptibility and duodenal biopsy examination. The 2023 American College of Gastroenterology guidelines recommend a biopsy-free approach in pediatric patients utilizing tissue transglutaminase antibody titers >10 times upper limit of normal and subsequent endomysial antibody seropositivity as sufficient for diagnosis. The objective of this study is to assess the diagnostic accuracy of biopsy-free approach at our pediatric hospital. METHODS: We conducted a retrospective study involving pediatric patients who underwent biopsy for diagnostic confirmation of celiac disease between May 2019 and May 2023. For these patients, the tissue transglutaminase and endomysial antibody test results were retrieved and performance of biopsy-free approach was assessed using the duodenal histology as the gold standard for celiac disease diagnosis. RESULTS: Tissue transglutaminase antibody titers >10 times upper limit of normal alone demonstrated a positive predictive value of 99% for identifying celiac disease in children. Although endomysial antibody testing is underutilized at our center, its inclusion further improved the predictability to 100 %. CONCLUSION: Positive predictive value of tissue transglutaminase antibody titers >10 times upper limit of normal is sufficiently high for celiac disease diagnosis in children and may allow for deferral of duodenal biopsy at diagnosis.


Assuntos
Doença Celíaca , Proteína 2 Glutamina gama-Glutamiltransferase , Criança , Humanos , Doença Celíaca/diagnóstico , Doença Celíaca/patologia , Estudos Retrospectivos , Transglutaminases , Proteínas de Ligação ao GTP , Imunoglobulina A , Biópsia , Autoanticorpos
15.
Int J Mol Sci ; 25(6)2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38542369

RESUMO

Arrestins are known to be involved not only in the desensitization and internalization of G protein-coupled receptors but also in the G protein-independent activation of mitogen-activated protein (MAP) kinases, such as extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK), to regulate cell proliferation and inflammation. Our previous study revealed that the histamine H1 receptor-mediated activation of ERK is dually regulated by Gq proteins and arrestins. In this study, we investigated the roles of Gq proteins and arrestins in the H1 receptor-mediated activation of JNK in Chinese hamster ovary (CHO) cells expressing wild-type (WT) human H1 receptors, the Gq protein-biased mutant S487TR, and the arrestin-biased mutant S487A. In these mutants, the Ser487 residue in the C-terminus region of the WT was truncated (S487TR) or mutated to alanine (S487A). Histamine significantly stimulated JNK phosphorylation in CHO cells expressing WT and S487TR but not S487A. Histamine-induced JNK phosphorylation in CHO cells expressing WT and S487TR was suppressed by inhibitors against H1 receptors (ketotifen and diphenhydramine), Gq proteins (YM-254890), and protein kinase C (PKC) (GF109203X) as well as an intracellular Ca2+ chelator (BAPTA-AM) but not by inhibitors against G protein-coupled receptor kinases (GRK2/3) (cmpd101), ß-arrestin2 (ß-arrestin2 siRNA), and clathrin (hypertonic sucrose). These results suggest that the H1 receptor-mediated phosphorylation of JNK is regulated by Gq-protein/Ca2+/PKC-dependent but GRK/arrestin/clathrin-independent pathways.


Assuntos
Arrestina , Histamina , Animais , Cricetinae , Humanos , Arrestina/metabolismo , Arrestinas/metabolismo , beta-Arrestinas/metabolismo , Células CHO , Clatrina/metabolismo , Cricetulus , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Quinases de Receptores Acoplados a Proteína G/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Histamina/farmacologia , Histamina/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Receptores Histamínicos H1/genética , Receptores Histamínicos H1/metabolismo , Transdução de Sinais
16.
Hypertension ; 81(5): e51-e62, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38445498

RESUMO

BACKGROUND: Arterial stiffness is a cardiovascular risk factor and dramatically increases as women transition through menopause. The current study assessed whether a mouse model of menopause increases arterial stiffness in a similar manner to aging and whether activation of the G-protein-coupled estrogen receptor could reverse stiffness. METHODS: Female C57Bl/6J mice were ovariectomized at 10 weeks of age or aged to 52 weeks, and some mice were treated with G-protein-coupled estrogen receptor agonists. RESULTS: Ovariectomy and aging increased pulse wave velocity to a similar extent independent of changes in blood pressure. Aging increased carotid wall thickness, while ovariectomy increased material stiffness without altering vascular geometry. RNA-sequencing analysis revealed that ovariectomy downregulated smooth muscle contractile genes. The enantiomerically pure G-protein-coupled estrogen receptor agonist, LNS8801, reversed stiffness in ovariectomy mice to a greater degree than the racemic agonist G-1. In summary, ovariectomy and aging induced arterial stiffening via potentially different mechanisms. Aging was associated with inward remodeling, while ovariectomy-induced material stiffness independent of geometry and a loss of the contractile phenotype. CONCLUSIONS: This study enhances our understanding of the impact of estrogen loss on vascular health in a murine model and warrants further studies to examine the ability of LNS8801 to improve vascular health in menopausal women.


Assuntos
Ovariectomia , Receptores Acoplados a Proteínas G , Rigidez Vascular , Animais , Feminino , Camundongos , Envelhecimento/fisiologia , Artérias Carótidas , Estrogênios/farmacologia , Proteínas de Ligação ao GTP , Ovariectomia/efeitos adversos , Análise de Onda de Pulso , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Rigidez Vascular/efeitos dos fármacos , Rigidez Vascular/fisiologia
17.
Int J Mol Sci ; 25(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474044

RESUMO

Transglutaminase type 2 (TG2) is the most ubiquitously expressed and well characterized member of the transglutaminase family. It is a ubiquitous multifunctional enzyme implicated in the regulation of several cellular pathways that support the survival, death, and general homeostasis of eukaryotic cells. Due to its multiple localizations both inside and outside the cell, TG2 participates in the regulation of many crucial intracellular signaling cascades in a tissue- and cell-specific manner, making this enzyme an important player in disease development and progression. Moreover, TG2 is capable of modulating the tumor microenvironment, a process of dynamic tissue remodeling and biomechanical events, resulting in changes which influence tumor initiation, growth, and metastasis. Even if generally related to the Ca2+-dependent post-translational modification of proteins, a number of different biological functions have been ascribed to TG2, like those of a peptide isomerase, protein kinase, guanine nucleotide binder, and cytosolic-nuclear translocator. With respect to cancer, TG2's role is controversial and highly debated; it has been described both as an anti- and pro-apoptotic factor and is linked to all the processes of tumorigenesis. However, numerous pieces of evidence support a tissue-specific role of TG2 so that it can assume both oncogenic and tumor-suppressive roles.


Assuntos
Neoplasias , Proteína 2 Glutamina gama-Glutamiltransferase , Humanos , Proteínas de Ligação ao GTP/metabolismo , Transglutaminases/metabolismo , Transdução de Sinais , Microambiente Tumoral
18.
Int J Mol Sci ; 25(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38474231

RESUMO

Melanoma, a highly aggressive skin cancer, is characterized by rapid progression and high mortality. Recent advances in molecular pathogenesis have shed light on genetic and epigenetic changes that drive melanoma development. This review provides an overview of these developments, focusing on molecular mechanisms in melanoma genesis. It highlights how mutations, particularly in the BRAF, NRAS, c-KIT, and GNAQ/GNA11 genes, affect critical signaling pathways. The evolution of diagnostic techniques, such as genomics, transcriptomics, liquid biopsies, and molecular biomarkers for early detection and prognosis, is also discussed. The therapeutic landscape has transformed with targeted therapies and immunotherapies, improving patient outcomes. This paper examines the efficacy, challenges, and prospects of these treatments, including recent clinical trials and emerging strategies. The potential of novel treatment strategies, including neoantigen vaccines, adoptive cell transfer, microbiome interactions, and nanoparticle-based combination therapy, is explored. These advances emphasize the challenges of therapy resistance and the importance of personalized medicine. This review underlines the necessity for evidence-based therapy selection in managing the increasing global incidence of melanoma.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/patologia , Neoplasias Cutâneas/patologia , Mutação , Transdução de Sinais , Proteínas de Ligação ao GTP/metabolismo
19.
J Food Sci ; 89(4): 2277-2291, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38488738

RESUMO

Calcium peptide chelates are developed as efficient supplements for preventing calcium deficiency. Spent hen meat (SHM) contains a high percentage of proteins but is generally wasted due to the disadvantages such as hard texture. We chose the underutilized SHM to produce peptides to bind calcium by proteolysis and aimed to investigate chelation between calcium and peptides in hydrolysate for a sustainable purpose. The optimized proteolysis conditions calculated from the result of response surface methodology for two-step hydrolysis were 0.30% (wenzyme/wmeat) for papain with a hydrolysis time of 3.5 h and 0.18% (wenzyme/wmeat) for flavourzyme with a hydrolysis time of 2.8 h. The enzymatic hydrolysate (EH) showed a binding capacity of 63.8 ± 1.8 mg calcium/g protein. Ethanol separation for EH improved the capacity up to a higher value of 68.6 ± 0.6 mg calcium/g protein with a high association constant of 420 M-1 (25°C) indicating high stability. The separated fraction with a higher amount of Glu, Asp, Lys, and Arg had higher calcium-binding capacity, which was related to the number of ─COOH and ─NH2 groups in peptide side chains according to the result from amino acid analysis and Fourier transform infrared spectroscopy. Two-step enzymatic hydrolysis and ethanol separation were an efficient combination to produce peptide mixtures derived from SHM with high calcium-binding capacity. The high percentage of hydrophilic amino acids in the separated fraction was concluded to increase calcium-binding capacity. This work provides foundations for increasing spent hen utilization and developing calcium peptide chelates based on underutilized meat.


Assuntos
Cálcio , Galinhas , Animais , Feminino , Cálcio/metabolismo , Galinhas/metabolismo , Hidrolisados de Proteína/química , Peptídeos/química , Hidrólise , Papaína/química , Aminoácidos , Cálcio da Dieta/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Carne , Etanol
20.
Int J Pharm ; 654: 123971, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38452832

RESUMO

Lymphoma and leukemia are both hematological system tumors with complex etiology, and mainly treated with chemotherapeutic drugs. However, therapeutic drugs can interrupt curative effect due to different side effects. Therefore, it is worthwhile to develop a novel therapeutic for providing insights for clinical tumor treatment. In this study, we developed a fisetin nanoparticles (Fisetin NPs) through a self-assembled method, and investigated the activity and potential mechanism of Fisetin NPs against lymphoma and leukemia. The spherical and uniformly distributed Fisetin NPs effectively inhibited both tumor cells proliferation, arrested EL4 cells G0/G1 phase and K562 cells G2/M phase, and induced apoptosis in vitro. In vivo, Fisetin NPs exhibited excellent tumor growth inhibition, effective inhibition of cell proliferation and angiogenesis, significant induction of apoptosis and ideal safety. Mechanically, fisetin upregulated genes (Fas, Pidd, Puma, Apaf1, and p21) in the p53 signaling pathway and bound to N-acetyltransferase 10 (NAT10), ribosomal protein L34 (RPL34) and GTP binding protein 4 (GTPBP4). Collectively, Fisetin NPs have promising therapeutic effects on lymphoma and leukemia, which are of great significant for clinical implications.


Assuntos
Leucemia , Linfoma , Humanos , Flavonoides/farmacologia , Flavonóis/farmacologia , Apoptose , Proliferação de Células , Leucemia/tratamento farmacológico , Linfoma/tratamento farmacológico , Linhagem Celular Tumoral , Proteínas Nucleares/farmacologia , Proteínas de Ligação ao GTP/farmacologia , Acetiltransferases N-Terminal
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