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1.
Cell ; 185(20): 3705-3719.e14, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36179667

RESUMO

The intestinal microbiota is an important modulator of graft-versus-host disease (GVHD), which often complicates allogeneic hematopoietic stem cell transplantation (allo-HSCT). Broad-spectrum antibiotics such as carbapenems increase the risk for intestinal GVHD, but mechanisms are not well understood. In this study, we found that treatment with meropenem, a commonly used carbapenem, aggravates colonic GVHD in mice via the expansion of Bacteroides thetaiotaomicron (BT). BT has a broad ability to degrade dietary polysaccharides and host mucin glycans. BT in meropenem-treated allogeneic mice demonstrated upregulated expression of enzymes involved in the degradation of mucin glycans. These mice also had thinning of the colonic mucus layer and decreased levels of xylose in colonic luminal contents. Interestingly, oral xylose supplementation significantly prevented thinning of the colonic mucus layer in meropenem-treated mice. Specific nutritional supplementation strategies, including xylose supplementation, may combat antibiotic-mediated microbiome injury to reduce the risk for intestinal GVHD in allo-HSCT patients.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacteroides , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/etiologia , Meropeném , Camundongos , Mucinas/metabolismo , Muco/metabolismo , Polissacarídeos/metabolismo , Xilose
2.
Mol Cell ; 81(13): 2722-2735.e9, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34077757

RESUMO

Lipid droplets are important for cancer cell growth and survival. However, the mechanism underlying the initiation of lipid droplet lipolysis is not well understood. We demonstrate here that glucose deprivation induces the binding of choline kinase (CHK) α2 to lipid droplets, which is sequentially mediated by AMPK-dependent CHKα2 S279 phosphorylation and KAT5-dependent CHKα2 K247 acetylation. Importantly, CHKα2 with altered catalytic domain conformation functions as a protein kinase and phosphorylates PLIN2 at Y232 and PLIN3 at Y251. The phosphorylated PLIN2/3 dissociate from lipid droplets and are degraded by Hsc70-mediated autophagy, thereby promoting lipid droplet lipolysis, fatty acid oxidation, and brain tumor growth. In addition, levels of CHKα2 S279 phosphorylation, CHKα2 K247 acetylation, and PLIN2/3 phosphorylation are positively correlated with one another in human glioblastoma specimens and are associated with poor prognosis in glioblastoma patients. These findings underscore the role of CHKα2 as a protein kinase in lipolysis and glioblastoma development.


Assuntos
Colina Quinase/metabolismo , Glioblastoma/enzimologia , Gotículas Lipídicas/enzimologia , Lipólise , Proteínas de Neoplasias/metabolismo , Proteínas Quinases/metabolismo , Acetilação , Linhagem Celular Tumoral , Colina Quinase/genética , Glioblastoma/genética , Humanos , Proteínas de Neoplasias/genética , Proteínas Quinases/genética
3.
Genes Dev ; 35(19-20): 1327-1332, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34531315

RESUMO

Activating mutations in KRAS (KRAS*) are present in nearly all pancreatic ductal adenocarcinoma (PDAC) cases and critical for tumor maintenance. By using an inducible KRAS* PDAC mouse model, we identified a deubiquitinase USP21-driven resistance mechanism to anti-KRAS* therapy. USP21 promotes KRAS*-independent tumor growth via its regulation of MARK3-induced macropinocytosis, which serves to maintain intracellular amino acid levels for anabolic growth. The USP21-mediated KRAS* bypass, coupled with the frequent amplification of USP21 in human PDAC tumors, encourages the assessment of USP21 as a novel drug target as well as a potential parameter that may affect responsiveness to emergent anti-KRAS* therapy.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Enzimas Desubiquitinantes/metabolismo , Camundongos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Ubiquitina Tiolesterase
4.
Mol Cell ; 76(3): 516-527.e7, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31492635

RESUMO

The PTEN tumor suppressor is frequently mutated or deleted in cancer and regulates glucose metabolism through the PI3K-AKT pathway. However, whether PTEN directly regulates glycolysis in tumor cells is unclear. We demonstrate here that PTEN directly interacts with phosphoglycerate kinase 1 (PGK1). PGK1 functions not only as a glycolytic enzyme but also as a protein kinase intermolecularly autophosphorylating itself at Y324 for activation. The protein phosphatase activity of PTEN dephosphorylates and inhibits autophosphorylated PGK1, thereby inhibiting glycolysis, ATP production, and brain tumor cell proliferation. In addition, knockin expression of a PGK1 Y324F mutant inhibits brain tumor formation. Analyses of human glioblastoma specimens reveals that PGK1 Y324 phosphorylation levels inversely correlate with PTEN expression status and are positively associated with poor prognosis in glioblastoma patients. This work highlights the instrumental role of PGK1 autophosphorylation in its activation and PTEN protein phosphatase activity in governing glycolysis and tumorigenesis.


Assuntos
Neoplasias Encefálicas/enzimologia , Glioblastoma/enzimologia , Glucose/metabolismo , Glicólise , PTEN Fosfo-Hidrolase/metabolismo , Fosfoglicerato Quinase/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Glioblastoma/genética , Glioblastoma/patologia , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , PTEN Fosfo-Hidrolase/genética , Fosfoglicerato Quinase/genética , Fosforilação , Prognóstico , Transdução de Sinais , Fatores de Tempo , Carga Tumoral , Tirosina
5.
Mol Cell ; 70(2): 197-210.e7, 2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29677490

RESUMO

EGFR activates phosphatidylinositide 3-kinase (PI3K), but the mechanism underlying this activation is not completely understood. We demonstrated here that EGFR activation resulted in lysine acetyltransferase 5 (KAT5)-mediated K395 acetylation of the platelet isoform of phosphofructokinase 1 (PFKP) and subsequent translocation of PFKP to the plasma membrane, where the PFKP was phosphorylated at Y64 by EGFR. Phosphorylated PFKP binds to the N-terminal SH2 domain of p85α, which is distinct from binding of Gab1 to the C-terminal SH2 domain of p85α, and recruited p85α to the plasma membrane resulting in PI3K activation. PI3K-dependent AKT activation results in enhanced phosphofructokinase 2 (PFK2) phosphorylation and production of fructose-2,6-bisphosphate, which in turn promotes PFK1 activation. PFKP Y64 phosphorylation-enhanced PI3K/AKT-dependent PFK1 activation and GLUT1 expression promoted the Warburg effect, tumor cell proliferation, and brain tumorigenesis. These findings underscore the instrumental role of PFKP in PI3K activation and enhanced glycolysis through PI3K/AKT-dependent positive-feedback regulation.


Assuntos
Neoplasias Encefálicas/enzimologia , Glioblastoma/enzimologia , Glicólise , Fosfatidilinositol 3-Quinases/metabolismo , Fosfofrutoquinase-1 Tipo C/metabolismo , Acetilação , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Classe Ia de Fosfatidilinositol 3-Quinase , Ativação Enzimática , Receptores ErbB/genética , Receptores ErbB/metabolismo , Retroalimentação Fisiológica , Frutosedifosfatos/metabolismo , Glioblastoma/genética , Glioblastoma/patologia , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Humanos , Lisina Acetiltransferase 5/genética , Lisina Acetiltransferase 5/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosfatidilinositol 3-Quinases/genética , Fosfofrutoquinase-1 Tipo C/genética , Fosfofrutoquinase-2/genética , Fosfofrutoquinase-2/metabolismo , Fosforilação , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Domínios de Homologia de src
6.
PLoS Pathog ; 19(1): e1011116, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36689489

RESUMO

Bat coronavirus RaTG13 shares about 96.2% nucleotide sequence identity with that of SARS-CoV-2 and uses human and Rhinolophus affinis (Ra) angiotensin-converting enzyme 2 (ACE2) as entry receptors. Whether there are bat species other than R. affinis susceptible to RaTG13 infection remains elusive. Here, we show that, among 18 different bat ACE2s tested, only RaACE2 is highly susceptible to transduction by RaTG13 S pseudovirions, indicating that the bat species harboring RaTG13 might be very limited. RaACE2 has seven polymorphic variants, RA-01 to RA-07, and they show different susceptibilities to RaTG13 S pseudovirions transduction. Sequence and mutagenesis analyses reveal that residues 34, 38, and 83 in RaACE2 might play critical roles in interaction with the RaTG13 S protein. Of note, RaACE2 polymorphisms have minimal effect on S proteins of SARS-CoV-2 and several SARS-CoV-2 related CoVs (SC2r-CoVs) including BANAL-20-52 and BANAL-20-236 in terms of binding, membrane fusion, and pseudovirus entry. Further mutagenesis analyses identify residues 501 and 505 in S proteins critical for the recognition of different RaACE2 variants and pangolin ACE2 (pACE2), indicating that RaTG13 might have not been well adapted to R. affinis bats. While single D501N and H505Y changes in RaTG13 S protein significantly enhance the infectivity and minimize the difference in susceptibility among different RaACE2 variants, an N501D substitution in SARS-CoV-2 S protein displays marked disparity in transduction efficiencies among RaACE2 variants with a significant reduction in infectivity on several RaACE2 variants. Finally, a T372A substitution in RaTG13 S protein not only significantly increases infectivity on all RaACE2 variants, but also markedly enhances entry on several bat ACE2s including R. sinicus YN, R. pearsonii, and R. ferrumeiqunum. However, the T372A mutant is about 4-fold more sensitive to neutralizing sera from mice immunized with BANAL-20-52 S, suggesting that the better immune evasion ability of T372 over A372 might contribute to the natural selective advantage of T372 over A372 among bat CoVs. Together, our study aids a better understanding of coronavirus entry, vaccine design, and evolution.


Assuntos
COVID-19 , Quirópteros , Animais , Camundongos , Humanos , SARS-CoV-2/metabolismo , Enzima de Conversão de Angiotensina 2 , Glicoproteína da Espícula de Coronavírus/metabolismo
7.
Hepatology ; 79(2): 425-437, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37611260

RESUMO

BACKGROUND AND AIMS: The predominantly progressive, indeterminate, and predominantly regressive (P-I-R) classification extends beyond staging and provides information on dynamic changes of liver fibrosis. However, the prognostic implication of P-I-R classification is not elucidated. Therefore, in the present research, we investigated the utility of P-I-R classification in predicting the on-treatment clinical outcomes. APPROACH AND RESULTS: In an extension study on a randomized controlled trial, we originally enrolled 1000 patients with chronic hepatitis B and biopsy-proven histological significant fibrosis, and treated them for more than 7 years with entecavir-based therapy. Among the 727 patients with a second biopsy at treatment week 72, we compared P-I-R classification and Ishak score changes in 646 patients with adequate liver sections for the histological evaluation. Progressive, indeterminate, and regressive cases were observed in 70%, 17%, and 13% of patients before treatments and 20%, 14%, and 64% after 72-week treatment, respectively, which could further differentiate the histological outcomes of patients with stable Ishak scores. The 7-year cumulative incidence of HCC was 1.5% for the regressive cases, 4.3% for the indeterminate cases, and 22.8% for the progressive cases ( p <0.001). After adjusting for age, treatment regimen, platelet counts, cirrhosis, Ishak fibrosis score changes, and Laennec staging, the posttreatment progressive had a HR of 17.77 (vs. posttreatment regressive; 95% CI: 5.55-56.88) for the incidence of liver-related events (decompensation, HCC, and death/liver transplantation). CONCLUSIONS: The P-I-R classification can be a meaningful complement to the Ishak fibrosis score not only in evaluating the histological changes but also in predicting the clinical outcomes.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Antivirais/uso terapêutico , Neoplasias Hepáticas/patologia , Cirrose Hepática/patologia , Fígado/patologia , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/patologia , Fibrose , Biópsia/efeitos adversos
8.
J Lipid Res ; 65(9): 100633, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39182608

RESUMO

Dynamin-related protein 1 (DRP1) plays crucial roles in mitochondrial and peroxisome fission. However, the mechanisms underlying the functional regulation of DRP1 in adipose tissue during obesity remain unclear. To elucidate the metabolic and pathological significance of diminished DRP1 in obese adipose tissue, we utilized adipose tissue-specific DRP1 KO mice challenged with a high-fat diet. We observed significant metabolic dysregulations in the KO mice. Mechanistically, DRP1 exerts multifaceted functions in mitochondrial dynamics and endoplasmic reticulum (ER)-lipid droplet crosstalk in normal mice. Loss of function of DRP1 resulted in abnormally giant mitochondrial shapes, distorted mitochondrial membrane structure, and disrupted cristae architecture. Meanwhile, DRP1 deficiency induced the retention of nascent lipid droplets in ER, leading to perturbed overall lipid dynamics in the KO mice. Collectively, dysregulation of the dynamics of mitochondria, ER, and lipid droplets contributes to whole-body metabolic disorders, as evidenced by perturbations in energy metabolites. Our findings demonstrate that DRP1 plays diverse and critical roles in regulating energy metabolism within adipose tissue during the progression of obesity.


Assuntos
Dinaminas , Animais , Masculino , Camundongos , Tecido Adiposo/metabolismo , Dieta Hiperlipídica/efeitos adversos , Dinaminas/metabolismo , Dinaminas/genética , Retículo Endoplasmático/metabolismo , Gotículas Lipídicas/metabolismo , Camundongos Knockout , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Obesidade/metabolismo
9.
J Biol Chem ; 299(9): 105185, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37611830

RESUMO

A substantial body of evidence has established the contributions of both mitochondrial dynamics and lipid metabolism to the pathogenesis of diabetic kidney disease (DKD). However, the precise interplay between these two key metabolic regulators of DKD is not fully understood. Here, we uncover a link between mitochondrial dynamics and lipid metabolism by investigating the role of carbohydrate-response element-binding protein (ChREBP), a glucose-responsive transcription factor and a master regulator of lipogenesis, in kidney podocytes. We find that inducible podocyte-specific knockdown of ChREBP in diabetic db/db mice improves key biochemical and histological features of DKD in addition to significantly reducing mitochondrial fragmentation. Because of the critical role of ChREBP in lipid metabolism, we interrogated whether and how mitochondrial lipidomes play a role in ChREBP-mediated mitochondrial fission. Our findings suggest a key role for a family of ether phospholipids in ChREBP-induced mitochondrial remodeling. We find that overexpression of glyceronephosphate O-acyltransferase, a critical enzyme in the biosynthesis of plasmalogens, reverses the protective phenotype of ChREBP deficiency on mitochondrial fragmentation. Finally, our data also points to Gnpat as a direct transcriptional target of ChREBP. Taken together, our results uncover a distinct mitochondrial lipid signature as the link between ChREBP-induced mitochondrial dynamics and progression of DKD.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Animais , Camundongos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Diabetes Mellitus/metabolismo , Nefropatias Diabéticas/metabolismo , Regulação da Expressão Gênica , Rim/metabolismo , Lipidômica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
10.
Crit Rev Eukaryot Gene Expr ; 34(4): 33-44, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505871

RESUMO

Acute myeloid leukemia (AML) is a highly heterogeneous disease. Exploring the pathogenesis of AML is still an important topic in the treatment of AML. The expression levels of miR-26b-5p and USP48 were measured by qRT-PCR. The expression levels of related proteins were detected by Western blot. Cell proliferation and apoptosis were detected by CCK-8 and flow cytometry, respectively. Coimmunoprecipitation was used to examine the interaction between USP48 and Wnt5a. Bioinformatics analysis showed that high levels of miR-26b-5p and low levels of USP48 were associated with poor prognosis in AML. miR-26b-5p can negatively regulate the expression of USP48. Downregulation of miR-26b-5p inhibited EMT, cell viability and proliferation of AML cells and accelerated apoptosis. Furthermore, the influence of miR-26b-5p inhibition and USP48 knockdown on AML progression could be reversed by a Wnt/ß-catenin signaling pathway inhibitor. This study revealed that miR-26b-5p regulates AML progression, possibly by targeting the USP48-mediated Wnt/ß-catenin molecular axis to affect AML cell biological behavior.


Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Via de Sinalização Wnt/genética , beta Catenina/genética , Western Blotting , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Proliferação de Células/genética , Linhagem Celular Tumoral , Apoptose/genética , Proteases Específicas de Ubiquitina/metabolismo
11.
Small ; 20(8): e2304082, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37767608

RESUMO

Bioenergetic deficits are known to be significant contributors to neurodegenerative diseases. Nevertheless, identifying safe and effective means to address intracellular bioenergetic deficits remains a significant challenge. This work provides mechanistic insights into the energy metabolism-regulating function of colloidal Au nanocrystals, referred to as CNM-Au8, that are synthesized electrochemically in the absence of surface-capping organic ligands. When neurons are subjected to excitotoxic stressors or toxic peptides, treatment of neurons with CNM-Au8 results in dose-dependent neuronal survival and neurite network preservation across multiple neuronal subtypes. CNM-Au8 efficiently catalyzes the conversion of an energetic cofactor, nicotinamide adenine dinucleotide hydride (NADH), into its oxidized counterpart (NAD+ ), which promotes bioenergy production by regulating the intracellular level of adenosine triphosphate. Detailed kinetic measurements reveal that CNM-Au8-catalyzed NADH oxidation obeys Michaelis-Menten kinetics and exhibits pH-dependent kinetic profiles. Photoexcited charge carriers and photothermal effect, which result from optical excitations and decay of the plasmonic electron oscillations or the interband electronic transitions in CNM-Au8, are further harnessed as unique leverages to modulate reaction kinetics. As exemplified by this work, Au nanocrystals with deliberately tailored structures and surfactant-free clean surfaces hold great promise for developing next-generation therapeutic agents for neurodegenerative diseases.


Assuntos
NAD , Doenças Neurodegenerativas , Humanos , NAD/química , Ouro/química , Oxirredução
12.
PLoS Pathog ; 18(5): e1010534, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35613180

RESUMO

The emerging "super fungus" Candida auris has become an important threat to human health due to its pandrug resistance and high lethality. Therefore, the development of novel antimicrobial strategy is essential. Antimicrobial photodynamic therapy (aPDT) has excellent performance in clinical applications. However, the relevant study on antifungal activity and the mechanism involved against C. auris remains scarce. Herein, a recyclable and biodegradable polylactic acid-hypocrellin A (PLA-HA) nanofibrous membrane is newly developed. In vitro PLA-HA-aPDT could significantly reduce the survival rate of C. auris plankton and its biofilms, and the fungicidal effect of the membrane is still significant after four repeated uses. Simultaneously, PLA-HA exhibits good biocompatibility and low hemolysis. In vivo experiments show that PLA-HA-aPDT can promote C. auris-infected wound healing, reduce inflammatory response, and without obvious toxic side-effects. Further results reveal that PLA-HA-aPDT could increase endogenous reactive oxygen species (ROS) levels, leading to mitochondrial dysfunction, release of cytochrome C, activation of metacaspase, and nuclear fragmentation, thereby triggering apoptosis of C. auris. Compared with HA, PLA-HA shows stronger controllability and reusability, which can greatly improve the utilization efficiency of HA alone. Taken together, the efficacy, safety and antifungal activity make PLA-HA-aPDT a highly promising antifungal candidate for skin or mucous membrane C. auris infection.


Assuntos
Candida , Nanofibras , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida auris , Humanos , Testes de Sensibilidade Microbiana , Poliésteres/farmacologia
13.
Theor Appl Genet ; 137(10): 219, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39254868

RESUMO

In the past century, there have been great achievements in identifying resistance (R) genes and quantitative trait loci (QTLs) as well as revealing the corresponding molecular mechanisms for resistance in rice to major diseases and insect pests. The introgression of R genes to develop resistant rice cultivars has become the most effective and eco-friendly method to control pathogens/insects at present. However, little attention has been paid to durable and broad-spectrum resistance, which determines the real applicability of R genes. Here, we summarize all the R genes and QTLs conferring durable and broad-spectrum resistance in rice to fungal blast, bacterial leaf blight (BLB), and the brown planthopper (BPH) in molecular breeding. We discuss the molecular mechanisms and feasible methods of improving durable and broad-spectrum resistance to blast, BLB, and BPH. We will particularly focus on pyramiding multiple R genes or QTLs as the most useful method to improve durability and broaden the disease/insect spectrum in practical breeding regardless of its uncertainty. We believe that this review provides useful information for scientists and breeders in rice breeding for multiple stress resistance in the future.


Assuntos
Resistência à Doença , Oryza , Melhoramento Vegetal , Doenças das Plantas , Locos de Características Quantitativas , Oryza/genética , Oryza/parasitologia , Oryza/microbiologia , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Doenças das Plantas/imunologia , Animais , Hemípteros/genética , Hemípteros/fisiologia , Insetos , Genes de Plantas
14.
Circ Res ; 131(1): 91-105, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35574856

RESUMO

BACKGROUND: Cellular redox control is maintained by generation of reactive oxygen/nitrogen species balanced by activation of antioxidative pathways. Disruption of redox balance leads to oxidative stress, a central causative event in numerous diseases including heart failure. Redox control in the heart exposed to hemodynamic stress, however, remains to be fully elucidated. METHODS: Pressure overload was triggered by transverse aortic constriction in mice. Transcriptomic and metabolomic regulations were evaluated by RNA-sequencing and metabolomics, respectively. Stable isotope tracer labeling experiments were conducted to determine metabolic flux in vitro. Neonatal rat ventricular myocytes and H9c2 cells were used to examine molecular mechanisms. RESULTS: We show that production of cardiomyocyte NADPH, a key factor in redox regulation, is decreased in pressure overload-induced heart failure. As a consequence, the level of reduced glutathione is downregulated, a change associated with fibrosis and cardiomyopathy. We report that the pentose phosphate pathway and mitochondrial serine/glycine/folate metabolic signaling, 2 NADPH-generating pathways in the cytosol and mitochondria, respectively, are induced by transverse aortic constriction. We identify ATF4 (activating transcription factor 4) as an upstream transcription factor controlling the expression of multiple enzymes in these 2 pathways. Consistently, joint pathway analysis of transcriptomic and metabolomic data reveal that ATF4 preferably controls oxidative stress and redox-related pathways. Overexpression of ATF4 in neonatal rat ventricular myocytes increases NADPH-producing enzymes' whereas silencing of ATF4 decreases their expression. Further, stable isotope tracer experiments reveal that ATF4 overexpression augments metabolic flux within these 2 pathways. In vivo, cardiomyocyte-specific deletion of ATF4 exacerbates cardiomyopathy in the setting of transverse aortic constriction and accelerates heart failure development, attributable, at least in part, to an inability to increase the expression of NADPH-generating enzymes. CONCLUSIONS: Our findings reveal that ATF4 plays a critical role in the heart under conditions of hemodynamic stress by governing both cytosolic and mitochondrial production of NADPH.


Assuntos
Insuficiência Cardíaca , Estresse Oxidativo , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Animais , Insuficiência Cardíaca/metabolismo , Camundongos , Miócitos Cardíacos/metabolismo , NADP/metabolismo , Estresse Oxidativo/fisiologia , Ratos , Espécies Reativas de Oxigênio/metabolismo
15.
Biomacromolecules ; 25(4): 2587-2596, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38527924

RESUMO

In response to increasing antibiotic resistance and the pressing demand for safer infected wound care, probiotics have emerged as promising bioactive agents. To address the challenges associated with the safe and efficient application of probiotics, this study successfully loaded metabolites from Lacticaseibacillus rhamnosus GG (LGG) into a gelatin cross-linked macromolecular network by an in situ blending and photopolymerization method. The obtained LM-GelMA possesses injectability and autonomous healing capabilities. Importantly, the incorporation of LGG metabolites endows LM-GelMA with excellent antibacterial properties against Staphylococcus aureus and Escherichia coli, while maintaining good biocompatibility. In vivo assessments revealed that LM-GelMA can accelerate wound healing by mitigating infections induced by pathogenic bacteria. This is accompanied by a reduction in the expression of key proinflammatory cytokines such as TNF-α, IL-6, VEGFR2, and TGF-ß, leading to increased re-epithelialization and collagen formation. Moreover, microbiological analysis confirmed that LM-GelMA can modulate the abundance of beneficial wound microbiota at family and genus levels. This study provides a facile strategy and insights into the functional design of hydrogels from the perspective of wound microenvironment regulation.


Assuntos
Lacticaseibacillus rhamnosus , Cicatrização , Antibacterianos/farmacologia , Citocinas , Escherichia coli , Hidrogéis/farmacologia
16.
Cladistics ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016633

RESUMO

Tooth attachment and replacement play significant roles in the feeding ecology of polyphyodont vertebrates, yet these aspects have remained largely unexplored in non-avialan paravians including troodontids. Here, we describe a new troodontid species, Urbacodon norelli sp.n., recovered from the Upper Cretaceous Iren Dabasu Formation of Inner Mongolia, China, based on an incomplete right dentary and 12 associated replacement teeth. Urbacodon norelli is distinguished from all other known troodontids, including its relative U. itemirensis from Uzbekistan, by several features: the presence of paired dentary symphyseal foramina, the presence of a relatively steep anterior margin of the dentary, the absence of a dentary chin, the presence of a common groove hosting the anterior 12 dentary teeth, and the presence of relatively larger dentary teeth. Phylogenetic analysis places both species of Urbacodon as sister taxa to Zanabazar junior, confirming their status as later-diverging troodontids. Radiographs revealed an alternating tooth replacement pattern in U. norelli, with a maximum Zahnreihen-spacing estimated to be 3. During tooth replacement, the anteriorly inclined interdental septa, which wedge between anterior dentary teeth, underwent frequent remodelling as the developing tooth moved upwards, particularly anterolabially. This rapid turnover left insufficient time for an interdental plate to form, resulting in the absence of such structures in this specimen. The frequent remodelling of periodontal tissues accompanying tooth replacement is likely to account for the absence of interdental plates. The discovery of this new troodontid expands our understanding of paravian theropods from the Upper Cretaceous Iren Dabasu Formation and provides valuable insights into troodontid tooth biology.

17.
Bioorg Chem ; 150: 107584, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38964146

RESUMO

Developing multitargeted ligands as promising therapeutics for Alzheimer's disease (AD) has been considered important. Herein, a novel class of cinnamamide/ester-triazole hybrids with multifaceted effects on AD was developed based on the multitarget-directed ligands strategy. Thirty-seven cinnamamide/ester-triazole hybrids were synthesized, with most exhibiting significant inhibitory activity against Aß-induced toxicity at a single concentration in vitro. The most optimal hybrid compound 4j inhibited copper-induced Aß toxicity in AD cells. its action was superior to that of donepezil and memantine. It also moderately inhibited intracellular AChE activity and presented favorable bioavailability and blood-brain barrier penetration with low toxicity in vivo. Of note, it ameliorated cognitive impairment, neuronal degeneration, and Aß deposition in Aß1-42-injured mice. Mechanistically, the compound regulated APP processing by promoting the ADAM10-associated nonamyloidogenic signaling and inhibiting the BACE1-mediated amyloidogenic pathway. Moreover, it suppressed intracellular AChE activity and tau phosphorylation. Therefore, compound 4j may be a promising multitargeted active molecule against AD.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Cinamatos , Triazóis , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Triazóis/química , Triazóis/farmacologia , Triazóis/síntese química , Cinamatos/química , Cinamatos/farmacologia , Cinamatos/síntese química , Humanos , Camundongos , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Relação Estrutura-Atividade , Estrutura Molecular , Ésteres/química , Ésteres/farmacologia , Ésteres/síntese química , Relação Dose-Resposta a Droga , Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/síntese química , Descoberta de Drogas , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/síntese química , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/antagonistas & inibidores , Masculino
18.
Environ Res ; 257: 119330, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38830394

RESUMO

Plant environmental stress response has become a global research hotspot, yet there is a lack of clear understanding regarding the mechanisms that maintain microbial diversity and their ecosystem services under environmental stress. In our research, we examined the effects of moderate elevation on the rhizosphere soil characteristics, microbial community composition, and ecosystem multifunctionality (EMF) within agricultural systems. Our findings revealed a notable negative correlation between EMF and elevation, indicating a decline in multifunctionality at higher elevations. Additionally, our analysis across bacterial and protistan communities showed a general decrease in microbial richness with increasing elevation. Using random forest models, pH was identified as the key environmental stressor influencing microbial communities. Furthermore, we found that microbial community diversity is negatively correlated with stability by mediating complexity. Interestingly, while pH was found to affect the complexity within bacterial networks, it did not significantly impact the ecosystem stability along the elevation gradients. Using a Binary-State Speciation and Extinction (BiSSE) model to explore the evolutionary dynamics, we found that Generalists had higher speciation rates and lower extinction rates compared to specialists, resulting in a skewed distribution towards higher net diversification for generalists under increasing environmental stress. Moreover, structural equation modeling (SEM) analysis highlighted a negative correlation between environmental stress and community diversity, but showed a positive correlation between environmental stress and degree of cooperation & competition. These interactions under environmental stress indirectly increased community stability and decreased multifunctionality. Our comprehensive study offers valuable insights into the intricate relationship among environmental factors, microbial communities, and ecosystem functions, especially in the context of varying elevation gradients. These findings contribute significantly to our understanding of how environmental stressors affect microbial diversity and ecosystem services, providing a foundation for future ecological research and management strategies in similar contexts.


Assuntos
Ecossistema , Microbiota , Microbiologia do Solo , Solo , Concentração de Íons de Hidrogênio , Solo/química , Altitude , Biodiversidade
19.
Qual Life Res ; 33(8): 2181-2195, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38839679

RESUMO

PURPOSE: Health-related quality-of-life (HRQoL) data for the chronic heart failure (HF) population in Malaysia are lacking. Using EQ-5D-5L, this study intended to describe their HRQoL, identify predictors of worse HRQoL, and derive EQ-5D-5L index scores for use in economic evaluations. METHODS: A cross-sectional survey was conducted between April and September 2023 to collect EQ-5D-5L, sociodemographic, and clinical data from outpatients with HF across seven public specialist hospitals in Malaysia. Multivariable logistic and linear regression models were used to identify independent predictors of reported problems in the EQ-5D-5L dimensions, and predictors of index scores and EQ-VAS, respectively. RESULTS: EQ-5D-5L data from 424 outpatients of multi-ethnic background (mean age: 57.1 years, 23.8% female, mean left ventricular ejection fraction: 35.7%, 89.7% NYHA class I-II) were collected using either Malay, English, or Chinese, achieving a 99.8% completion rate. Nearly half of the respondents reported issues in the Mobility, Usual Activities, and Pain/Discomfort dimensions. Mean EQ-5D-5L index was 0.820, lower than the general population, and significantly lower with NYHA class III-IV (0.747) versus NYHA class I (0.846) and NYHA class II (0.805). Besides NYHA class, independent predictors of worse HRQoL included Indian ethnicity, living alone, lower education, unemployment due to ill-health, and proxy-reported HRQoL, largely aligning with existing literature. CONCLUSION: Community-dwelling Malaysians with HF reported poorer HRQoL compared to the general population. The observed disparities in HRQoL among HF patients may be linked to specific patient characteristics, suggesting potential areas for targeted interventions. HRQoL assessment using EQ-5D-5L proves feasible and should be considered for routine implementation in local clinics.


Assuntos
Insuficiência Cardíaca , Qualidade de Vida , Humanos , Feminino , Masculino , Insuficiência Cardíaca/psicologia , Malásia , Estudos Transversais , Pessoa de Meia-Idade , Idoso , Inquéritos e Questionários , Doença Crônica , Adulto , Pacientes Ambulatoriais/psicologia , Nível de Saúde , Psicometria
20.
BMC Pulm Med ; 24(1): 242, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755605

RESUMO

INTRODUCTION: Lung cancer is a common malignant tumor, and different types of immune cells may have different effects on the occurrence and development of lung cancer subtypes, including lung squamous cell carcinoma (LUSC) and lung adenocarcinoma (LUAD). However, the causal relationship between immune phenotype and lung cancer is still unclear. METHODS: This study utilized a comprehensive dataset containing 731 immune phenotypes from the European Bioinformatics Institute (EBI) to evaluate the potential causal relationship between immune phenotypes and LUSC and LUAD using the inverse variance weighted (IVW) method in Mendelian randomization (MR). Sensitivity analyses, including MR-Egger intercept, Cochran Q test, and others, were conducted for the robustness of the results. The study results were further validated through meta-analysis using data from the Transdisciplinary Research Into Cancer of the Lung (TRICL) data. Additionally, confounding factors were excluded to ensure the robustness of the findings. RESULTS: Among the final selection of 729 immune cell phenotypes, three immune phenotypes exhibited statistically significant effects with LUSC. CD28 expression on resting CD4 regulatory T cells (OR 1.0980, 95% CI: 1.0627-1.1344, p < 0.0001) and CD45RA + CD28- CD8 + T cell %T cell (OR 1.0011, 95% CI: 1.0007; 1.0015, p < 0.0001) were associated with increased susceptibility to LUSC. Conversely, CCR2 expression on monocytes (OR 0.9399, 95% CI: 0.9177-0.9625, p < 0.0001) was correlated with a decreased risk of LUSC. However, no significant causal relationships were established between any immune cell phenotypes and LUAD. CONCLUSION: This study demonstrates that specific immune cell types are associated with the risk of LUSC but not with LUAD. While these findings are derived solely from European populations, they still provide clues for a deeper understanding of the immunological mechanisms underlying lung cancer and may offer new directions for future therapeutic strategies and preventive measures.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Análise da Randomização Mendeliana , Fenótipo , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/imunologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Receptores CCR2/genética , Linfócitos T CD8-Positivos/imunologia , Antígenos CD28/genética
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