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1.
Proc Natl Acad Sci U S A ; 121(28): e2405473121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38950361

RESUMO

Cycling cells replicate their DNA during the S phase through a defined temporal program known as replication timing. Mutation frequencies, epigenetic chromatin states, and transcriptional activities are different for genomic regions that are replicated early and late in the S phase. Here, we found from ChIP-Seq analysis that DNA polymerase (Pol) κ is enriched in early-replicating genomic regions in HEK293T cells. In addition, by feeding cells with N 2-heptynyl-2'-deoxyguanosine followed by click chemistry-based enrichment and high-throughput sequencing, we observed elevated Pol κ activities in genomic regions that are replicated early in the S phase. On the basis of the established functions of Pol κ in accurate and efficient nucleotide insertion opposite endogenously induced N 2-modified dG lesions, our work suggests that active engagement of Pol κ may contribute to diminished mutation rates observed in early-replicating regions of the human genome, including cancer genomes. Together, our work expands the functions of Pol κ and offered a plausible mechanism underlying replication timing-dependent mutation accrual in the human genome.


Assuntos
Replicação do DNA , DNA Polimerase Dirigida por DNA , Fase S , Humanos , DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/genética , Células HEK293 , Genoma Humano , Período de Replicação do DNA
2.
Proc Natl Acad Sci U S A ; 121(37): e2403421121, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39226350

RESUMO

Drug-resistant Tuberculosis (TB) is a global public health problem. Resistance to rifampicin, the most effective drug for TB treatment, is a major growing concern. The etiological agent, Mycobacterium tuberculosis (Mtb), has a cluster of ATP-binding cassette (ABC) transporters which are responsible for drug resistance through active export. Here, we describe studies characterizing Mtb Rv1217c-1218c as an ABC transporter that can mediate mycobacterial resistance to rifampicin and have determined the cryo-electron microscopy structures of Rv1217c-1218c. The structures show Rv1217c-1218c has a type V exporter fold. In the absence of ATP, Rv1217c-1218c forms a periplasmic gate by two juxtaposed-membrane helices from each transmembrane domain (TMD), while the nucleotide-binding domains (NBDs) form a partially closed dimer which is held together by four salt-bridges. Adenylyl-imidodiphosphate (AMPPNP) binding induces a structural change where the NBDs become further closed to each other, which downstream translates to a closed conformation for the TMDs. AMPPNP binding results in the collapse of the outer leaflet cavity and the opening of the periplasmic gate, which was proposed to play a role in substrate export. The rifampicin-bound structure shows a hydrophobic and periplasm-facing cavity is involved in rifampicin binding. Phospholipid molecules are observed in all determined structures and form an integral part of the Rv1217c-1218c transporter system. Our results provide a structural basis for a mycobacterial ABC exporter that mediates rifampicin resistance, which can lead to different insights into combating rifampicin resistance.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Proteínas de Bactérias , Microscopia Crioeletrônica , Farmacorresistência Bacteriana , Mycobacterium tuberculosis , Rifampina , Rifampina/farmacologia , Rifampina/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/ultraestrutura , Transportadores de Cassetes de Ligação de ATP/genética , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/ultraestrutura , Proteínas de Bactérias/genética , Modelos Moleculares , Adenilil Imidodifosfato/metabolismo
3.
Proc Natl Acad Sci U S A ; 121(28): e2404062121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38968109

RESUMO

Nutrient sensing and adaptation in the placenta are essential for pregnancy viability and proper fetal growth. Our recent study demonstrated that the placenta adapts to nutrient insufficiency through mechanistic target of rapamycin (mTOR) inhibition-mediated trophoblast differentiation toward syncytiotrophoblasts (STBs), a highly specialized multinucleated trophoblast subtype mediating extensive maternal-fetal interactions. However, the underlying mechanism remains elusive. Here, we unravel the indispensable role of the mTORC1 downstream transcriptional factor TFEB in STB formation both in vitro and in vivo. TFEB deficiency significantly impaired STB differentiation in human trophoblasts and placenta organoids. Consistently, systemic or trophoblast-specific deletion of Tfeb compromised STB formation and placental vascular construction, leading to severe embryonic lethality. Mechanistically, TFEB conferred direct transcriptional activation of the fusogen ERVFRD-1 in human trophoblasts and thereby promoted STB formation, independent of its canonical function as a master regulator of the autophagy-lysosomal pathway. Moreover, we demonstrated that TFEB directed the trophoblast syncytialization response driven by mTOR complex 1 (mTORC1) signaling. TFEB expression positively correlated with the reinforced trophoblast syncytialization in human fetal growth-restricted placentas exhibiting suppressed mTORC1 activity. Our findings substantiate that the TFEB-fusogen axis ensures proper STB formation during placenta development and under nutrient stress, shedding light on TFEB as a mechanistic link between nutrient-sensing machinery and trophoblast differentiation.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Diferenciação Celular , Alvo Mecanístico do Complexo 1 de Rapamicina , Trofoblastos , Trofoblastos/metabolismo , Humanos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Feminino , Gravidez , Camundongos , Animais , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Placenta/metabolismo , Transdução de Sinais , Autofagia/fisiologia
4.
Nucleic Acids Res ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39351875

RESUMO

Humans are exposed to DNA alkylating agents through endogenous metabolism, environmental exposure and cancer chemotherapy. The resulting alkylated DNA adducts may elicit genome instability by perturbing DNA replication and transcription. R-loops regulate various cellular processes, including transcription, DNA repair, and telomere maintenance. However, unscheduled R-loops are also recognized as potential sources of DNA damage and genome instability. In this study, by employing fluorescence microscopy and R-loop sequencing approaches, we uncovered, for the first time, that minor-groove N2-alkyl-dG lesions elicit elevated R-loop accumulation in chromatin and in plasmid DNA in cells. We also demonstrated that the N2-alkyl-dG-induced R-loops impede transcription elongation and compromise genome integrity. Moreover, genetic depletion of DDX23, a R-loop helicase, renders cells more sensitive toward benzo[a]pyrene diolepoxide, a carcinogen that induces mainly the minor-groove N2-dG adduct. Together, our work unveiled that unrepaired minor-groove N2-alkyl-dG lesions may perturb genome integrity through augmenting R-loop levels in chromatin. Our findings suggest a potential therapeutic strategy involving the combination of R-loop helicase inhibitors with DNA alkylating drugs.

5.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38168840

RESUMO

Gestational diabetes mellitus (GDM) is a common complication of pregnancy, which has significant adverse effects on both the mother and fetus. The incidence of GDM is increasing globally, and early diagnosis is critical for timely treatment and reducing the risk of poor pregnancy outcomes. GDM is usually diagnosed and detected after 24 weeks of gestation, while complications due to GDM can occur much earlier. Copy number variations (CNVs) can be a possible biomarker for GDM diagnosis and screening in the early gestation stage. In this study, we proposed a machine-learning method to screen GDM in the early stage of gestation using cell-free DNA (cfDNA) sequencing data from maternal plasma. Five thousand and eighty-five patients from north regions of Mainland China, including 1942 GDM, were recruited. A non-overlapping sliding window method was applied for CNV coverage screening on low-coverage (~0.2×) sequencing data. The CNV coverage was fed to a convolutional neural network with attention architecture for the binary classification. The model achieved a classification accuracy of 88.14%, precision of 84.07%, recall of 93.04%, F1-score of 88.33% and AUC of 96.49%. The model identified 2190 genes associated with GDM, including DEFA1, DEFA3 and DEFB1. The enriched gene ontology (GO) terms and KEGG pathways showed that many identified genes are associated with diabetes-related pathways. Our study demonstrates the feasibility of using cfDNA sequencing data and machine-learning methods for early diagnosis of GDM, which may aid in early intervention and prevention of adverse pregnancy outcomes.


Assuntos
Ácidos Nucleicos Livres , Aprendizado Profundo , Diabetes Gestacional , beta-Defensinas , Feminino , Gravidez , Humanos , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/genética , Variações do Número de Cópias de DNA , Resultado da Gravidez , Ácidos Nucleicos Livres/genética
6.
Cereb Cortex ; 34(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39042033

RESUMO

We aimed to evaluate the potential causal relationship between brain imaging-derived phenotypes and cognitive functions via Mendelian randomization analyses. Genetic instruments for 470 brain imaging-derived phenotypes were selected from a genome-wide association study based on the UK Biobank (n = 33,224). Statistics for cognitive functions were obtained from the genome-wide association study based on the UK Biobank. We used the inverse variance weighted Mendelian randomization method to investigate the associations between brain imaging-derived phenotypes and cognitive functions, and reverse Mendelian randomization analyses were performed for significant brain imaging-derived phenotypes to examine the reverse causation for the identified associations. We identified three brain imaging-derived phenotypes to be associated with verbal-numerical reasoning, including cortical surface area of the left fusiform gyrus (beta, 0.18 [95% confidence interval, 0.11 to 0.25], P = 4.74 × 10-7), cortical surface area of the right superior temporal gyrus (beta, 0.25 [95% confidence interval, 0.15 to 0.35], P = 6.30 × 10-7), and orientation dispersion in the left superior longitudinal fasciculus (beta, 0.14 [95% confidence interval, 0.09 to 0.20], P = 8.37 × 10-7). The reverse Mendelian randomization analysis indicated that verbal-numerical reasoning had no effect on these three brain imaging-derived phenotypes. This Mendelian randomization study identified cortical surface area of the left fusiform gyrus, cortical surface area of the right superior temporal gyrus, and orientation dispersion in the left superior longitudinal fasciculus as predictors of verbal-numerical reasoning.


Assuntos
Encéfalo , Cognição , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Fenótipo , Humanos , Cognição/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Masculino , Feminino , Neuroimagem/métodos , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Idoso
7.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38185989

RESUMO

Previous observational studies have reported associations between brain imaging-derived phenotypes (IDPs) and intracerebral hemorrhage (ICH), but the causality between them remains uncertain. We aimed to investigate the potential causal relationship between IDPs and ICH by a two-sample Mendelian randomization (MR) study. We selected genetic instruments for 363 IDPs from a genome-wide association study (GWASs) based on the UK Biobank (n = 33,224). Summary-level data on ICH was derived from a European-descent GWAS with 1,545 cases and 1,481 controls. Inverse variance weighted MR method was applied in the main analysis to investigate the associations between IDPs and ICH. Reverse MR analyses were performed for significant IDPs to examine the reverse causation for the identified associations. Among the 363 IDPs, isotropic or free water volume fraction (ISOVF) in the anterior limb of the left internal capsule was identified to be associated with the risk of ICH (OR per 1-SD increase, 4.62 [95% CI, 2.18-9.81], P = 6.63 × 10-5). In addition, the reverse MR analysis indicated that ICH had no effect on ISOVF in the anterior limb of the left internal capsule (beta, 0.010 [95% CI, -0.010-0.030], P = 0.33). MR-Egger regression analysis showed no directional pleiotropy for the association between ISOVF and ICH, and sensitivity analyses with different MR models further confirmed these findings. ISOVF in the anterior limb of the left internal capsule might be a potential causal mediator of ICH, which may provide predictive guidance for the prevention of ICH. Further studies are warranted to replicate our findings and clarify the underlying mechanisms.


Assuntos
Estudo de Associação Genômica Ampla , Humanos , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/genética , Análise da Randomização Mendeliana , Neuroimagem , Fenótipo
8.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38112636

RESUMO

Brain imaging-derived phenotypes have been suggested to be associated with amyotrophic lateral sclerosis in observational studies, but whether these associations are causal remains unclear. We aimed to assess the potential bidirectional causal associations between imaging-derived phenotypes and amyotrophic lateral sclerosis using bidirectional 2-sample Mendelian randomization analyses. Summary statistics for 469 imaging-derived phenotypes (33,224 individuals) and amyotrophic lateral sclerosis (20,806 cases and 59,804 controls) were obtained from 2 large-scale genome-wide association studies of European ancestry. We used the inverse-variance weighted Mendelian randomization method in the main analysis to assess the bidirectional associations between imaging-derived phenotypes and amyotrophic lateral sclerosis, followed by several sensitivity analyses for robustness validation. In the forward Mendelian randomization analyses, we found that genetically determined high orientation dispersion index in the right cerebral peduncle was associated with the increased risk of amyotrophic lateral sclerosis (odds ratio = 1.30, 95% confidence interval = 1.16-1.45, P = 2.26 × 10-6). In addition, the reverse Mendelian randomization analysis indicated that amyotrophic lateral sclerosis had no effect on 469 imaging-derived phenotypes. Mendelian randomization-Egger regression analysis showed no directional pleiotropy for the association between high orientation dispersion index in the right cerebral peduncle and amyotrophic lateral sclerosis, and sensitivity analyses with different Mendelian randomization models further confirmed these findings. The present systematic bidirectional Mendelian randomization analysis showed that high orientation dispersion index in the right cerebral peduncle might be the potential causal mediator of amyotrophic lateral sclerosis, which may provide predictive guidance for the prevention of amyotrophic lateral sclerosis. Further studies are warranted to replicate our findings and clarify the underlying mechanisms.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/diagnóstico por imagem , Esclerose Lateral Amiotrófica/genética , Encéfalo/diagnóstico por imagem , Estudo de Associação Genômica Ampla , Neuroimagem , Fenótipo , Polimorfismo de Nucleotídeo Único , Análise da Randomização Mendeliana
9.
Nucleic Acids Res ; 51(10): 4745-4759, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-36864754

RESUMO

Endogenous retroviruses (ERVs) have been proposed as a driving force for the evolution of the mammalian placenta, however, the contribution of ERVs to placental development and the underlying regulatory mechanism remain largely elusive. A key process of placental development is the formation of multinucleated syncytiotrophoblasts (STBs) in direct contact with maternal blood, through which constitutes the maternal-fetal interface critical for nutrient allocation, hormone production and immunological modulation during pregnancy. We delineate that ERVs profoundly rewire the transcriptional program of trophoblast syncytialization. Here, we first determined the dynamic landscape of bivalent ERV-derived enhancers with dual occupancy of H3K27ac and H3K9me3 in human trophoblast stem cells (hTSCs). We further demonstrated that enhancers overlapping several ERV families tend to exhibit increased H3K27ac and reduced H3K9me3 occupancy in STBs relative to hTSCs. Particularly, bivalent enhancers derived from the Simiiformes-specific MER50 transposons were linked to a cluster of genes important for STB formation. Importantly, deletions of MER50 elements adjacent to several STB genes, including MFSD2A and TNFAIP2, significantly attenuated their expression concomitant to compromised syncytium formation. Together, we propose that ERV-derived enhancers, MER50 specifically, fine-tune the transcriptional networks accounting for human trophoblast syncytialization, which sheds light on a novel ERV-mediated regulatory mechanism underlying placental development.


Assuntos
Retrovirus Endógenos , Elementos Facilitadores Genéticos , Placenta , Trofoblastos , Animais , Feminino , Humanos , Gravidez , Retrovirus Endógenos/genética , Regulação da Expressão Gênica , Mamíferos/crescimento & desenvolvimento , Placenta/citologia , Placenta/fisiologia , Trofoblastos/fisiologia
10.
Stroke ; 55(6): 1535-1542, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38572663

RESUMO

BACKGROUND: Observational studies suggest that hepatocyte growth factor (HGF) is associated with the risk and prognosis of ischemic stroke, but the causality of these associations remains unclear. Therefore, we conducted Mendelian randomization (MR) analyses to explore the associations of genetically determined plasma HGF levels with the risk and prognosis of ischemic stroke. METHODS: A total of 13 single-nucleotide polymorphisms associated with plasma HGF were selected as genetic instruments based on the data from a genome-wide association study with 21 758 European participants. Summary data about the risk of ischemic stroke were obtained from the MEGASTROKE (Multiancestry Genome-Wide Association Study of Stroke) Consortium with 34 217 ischemic stroke cases and 406 111 controls of European ancestry, and summary data about the prognosis of ischemic stroke were obtained from the GISCOME study (Genetics of Ischaemic Stroke Functional Outcome) with 6165 European patients with ischemic stroke. We conducted an inverse-variance weighted Mendelian randomization analysis followed by a series of sensitivity analyses to evaluate the associations of genetically determined plasma HGF with the risk and prognosis of ischemic stroke. RESULTS: The primary analyses showed that genetically determined high HGF was associated with an increased risk of ischemic stroke (odds ratio per SD increase, 1.11 [95% CI, 1.04-1.19]; P=1.10×10-3) and poor prognosis of ischemic stroke (odds ratio per SD increase, 2.43 [95% CI, 1.76-3.52]; P=6.35×10-8). In the secondary analysis, genetically determined plasma HGF was associated with a high risk of large atherosclerotic stroke (odds ratio per SD increase, 1.39 [95% CI, 1.18-1.63]; P=5.08×10-5) but not small vessel stroke and cardioembolic stroke. Mendelian randomization-Egger regression showed no directional pleiotropy for all associations, and the sensitivity analyses with different Mendelian randomization methods further confirmed these findings. CONCLUSIONS: We found positive associations of genetically determined plasma HGF with the risk and prognosis of ischemic stroke, suggesting that HGF might be implicated in the occurrence and development of ischemic stroke.


Assuntos
Estudo de Associação Genômica Ampla , Fator de Crescimento de Hepatócito , AVC Isquêmico , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Humanos , Fator de Crescimento de Hepatócito/sangue , Fator de Crescimento de Hepatócito/genética , AVC Isquêmico/sangue , AVC Isquêmico/genética , Prognóstico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Isquemia Encefálica/sangue , Isquemia Encefálica/genética
11.
J Am Chem Soc ; 146(32): 22553-22562, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39101269

RESUMO

N2-Alkyl-2'-deoxyguanosine (N2-alkyl-dG) is a major type of minor-groove DNA lesions arising from endogenous metabolic processes and exogenous exposure to environmental contaminants. The N2-alkyl-dG lesions, if left unrepaired, can block DNA replication and transcription and induce mutations in these processes. Nevertheless, the repair pathways for N2-alkyl-dG lesions remain incompletely elucidated. By utilizing a photo-cross-linking coupled with mass spectrometry-based quantitative proteomic analysis, we identified a series of candidate N2-alkyl-dG-binding proteins. We found that two of these proteins, i.e., high-mobility group protein B3 (HMGB3) and SUB1, could bind directly to N2-nBu-dG-containing duplex DNA in vitro and promote the repair of this lesion in cultured human cells. In addition, HMGB3 and SUB1 protected cells against benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE). SUB1 exhibits preferential binding to both the cis and trans diastereomers of N2-BPDE-dG over unmodified dG. On the other hand, HMGB3 binds favorably to trans-N2-BPDE-dG; the protein, however, does not distinguish cis-N2-BPDE-dG from unmodified dG. Consistently, genetic ablation of HMGB3 conferred diminished repair of trans-N2-BPDE-dG, but not its cis counterpart, whereas loss of SUB1 conferred attenuated repair of both diastereomers. Together, we identified proteins involved in the cellular sensing and repair of minor-groove N2-alkyl-dG lesions and documented a unique role of HMGB3 in the stereospecific recognition and repair of N2-BPDE-dG.


Assuntos
Reparo do DNA , DNA , Proteína HMGB3 , Humanos , DNA/química , DNA/metabolismo , Dano ao DNA , Enzimas Reparadoras do DNA , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/química , Guanina/química , Guanina/metabolismo , Proteína HMGB3/metabolismo , Proteína HMGB3/química , Ligação Proteica
12.
Small ; 20(1): e2304618, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37635111

RESUMO

The development of lithium-sulfur (Li-S) batteries is very promising and yet faces the issues of hindered polysulfides conversion and Li dendrite growth. Different from using different materials strategies to overcome these two types of problems, here multifunctional catalytic hierarchical interfaces of Ni12 P5 -Ni2 P porous nanosheets formed by Ni2 P partially in situ converted from Ni12 P5 are proposed. The unique electronic structure in the interface endows Ni12 P5 -Ni2 P effective electrocatalysis effect toward both sulfides' reduction and oxidation through reducing Gibbs free energies, indicating a bidirectional conversion acceleration. Importantly, Ni12 P5 -Ni2 P porous nanosheets with hierarchical interfaces also reduced the Li nucleation energy barrier, and a dendrite-free Li deposition is realized during the overall Li deposition and stripping steps. To this end, Ni12 P5 -Ni2 P decorated carbon nanotube/S cathode showing a high capacity of over 1500 mAh g-1 , and a high rate capability of 8 C. Moreover, the coin full cell delivered a high capacity of 1345 mAh g-1 at 0.2 C and the pouch full cell delivered a high capacity of 1114 mAh g-1 at 0.2 C with high electrochemical stability during 180° bending. This work inspires the exploration of hierarchical structures of 2D materials with catalytically active interfaces to improve the electrochemistry of Li-S full battery.

13.
BMC Microbiol ; 24(1): 73, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443783

RESUMO

BACKGROUND: Undernutrition (UN) is a critical public health issue that threatens the lives of children under five in developing countries. While evidence indicates the crucial role of the gut microbiome (GM) in UN pathogenesis, the strain-level inspection and bacterial co-occurrence network investigation in the GM of UN children are lacking. RESULTS: This study examines the strain compositions of the GM in 61 undernutrition patients (UN group) and 36 healthy children (HC group) and explores the topological features of GM co-occurrence networks using a complex network strategy. The strain-level annotation reveals that the differentially enriched species between the UN and HC groups are due to discriminated strain compositions. For example, Prevotella copri is mainly composed of P. copri ASM1680343v1 and P. copri ASM345920v1 in the HC group, but it is composed of P. copri ASM346549v1 and P. copri ASM347465v1 in the UN group. In addition, the UN-risk model constructed at the strain level demonstrates higher accuracy (AUC = 0.810) than that at the species level (AUC = 0.743). With complex network analysis, we further discovered that the UN group had a more complex GM co-occurrence network, with more hub bacteria and a higher clustering coefficient but lower information transfer efficiencies. Moreover, the results at the strain level suggested the inaccurate and even false conclusions obtained from species level analysis. CONCLUSIONS: Overall, this study highlights the importance of examining the GM at the strain level and investigating bacterial co-occurrence networks to advance our knowledge of UN pathogenesis.


Assuntos
Microbioma Gastrointestinal , Desnutrição , Criança , Humanos , Análise por Conglomerados , Saúde Pública
14.
J Hum Genet ; 69(11): 565-571, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38951193

RESUMO

Observational studies suggested increased risks of Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS) in patients with Crohn's disease (CD) and ulcerative colitis (UC). We aimed to assess the causality for the associations of CD and UC with the risks of AD, PD, and MS through a two-sample Mendelian randomization (MR) study. Independent single nucleotide polymorphisms associated with CD (17,897 cases and 33,977 controls) and UC (13,768 cases and 33,977 controls) were identified as genetic instruments based on a European-descent genome-wide association study (GWAS) released by the International Inflammatory Bowel Disease Genetics Consortium. Summary statistics for AD (combined: 25,881 cases and 256,837 controls), PD (combined: 35,836 cases and 665,686 controls), and MS (combined: 48,477 cases and 285,515 controls) were obtained from the largest GWASs and FinnGen study of European ancestry, respectively. MR estimates were generated using the inverse-variance weighted method in the main analysis with a series of sensitivity analyses. MR analyses were conducted per outcome database and were subsequently meta-analyzed to generate combined estimates. Genetically predicted UC was significantly associated with increased risks of AD (combined: OR, 1.03; 95% CI, 1.01-1.05; P = 1.80 × 10-3) and MS (combined: OR, 1.37; 95% CI, 1.23-1.53; P = 1.18 × 10-8), while there was no association between genetically predicted UC and the risk of PD. In contrast, no significant associations were observed for genetically predicted CD with AD, PD, and MS. MR-Egger regression showed no directional pleiotropy for the identified associations, and sensitivity analyses with different MR methods further confirmed these findings. This study suggested significant adverse effects of UC on AD and MS, highlighting that UC patients should receive early intervention with optimal adjunctive medical therapy to reduce the risks of AD and MS.


Assuntos
Colite Ulcerativa , Doença de Crohn , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Humanos , Doença de Crohn/genética , Doença de Crohn/epidemiologia , Colite Ulcerativa/genética , Colite Ulcerativa/epidemiologia , Fatores de Risco , Esclerose Múltipla/genética , Esclerose Múltipla/epidemiologia , Doença de Parkinson/genética , Doença de Parkinson/epidemiologia , Doença de Alzheimer/genética , Doença de Alzheimer/epidemiologia , Estudos de Casos e Controles , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/epidemiologia
15.
Microvasc Res ; 151: 104614, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37802365

RESUMO

Bladder cancer (BLCA) is a common type of urogenital malignancy worldwide. The recurrence and metastasis of bladder cancer are closely related to angiogenesis, but the underlying mechanisms are unclear. In this study, we developed a method to predict survival outcomes among BLCA patients, which could be used to guide immunotherapy and chemotherapy. We obtained patient data from The Cancer Genome Atlas (TCGA) and identified angiogenesis-related genes from the GeneCards database. First, we used differential expression analysis and univariate Cox analysis to identify angiogenesis-related genes and used correlation analysis to generate molecular subtypes based on M2 macrophages. Next, we constructed a prognostic signature consisting of four genes (ECM1, EFEMP1, SLIT2, and PDGFRΑ), which was found to be an independent prognostic factor. Higher risk scores were associated with worse overall survival and higher expression of immune checkpoints. We also evaluated immune cell infiltration using the CIBERSORT and ssGSEA algorithms. Additionally, we performed stratification analyses, constructed a nomogram, and predicted chemotherapeutic responses based on the risk signature. Finally, we validated our findings by using qRT-PCR as well as IHC data to detect the expression levels of the four genes at mRNA and protein levels in BLCA patients and obtained results that were consistent with our predictions. Our study demonstrates the utility of a four-gene prognostic signature for prognostication in bladder cancer patients and designing personalized treatments, which could provide new avenues for personalized management of these patients.


Assuntos
Microambiente Tumoral , Neoplasias da Bexiga Urinária , Humanos , Algoritmos , Angiogênese , Bases de Dados Factuais , Proteínas da Matriz Extracelular , Prognóstico , Neoplasias da Bexiga Urinária/genética
16.
BMC Cancer ; 24(1): 673, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38825709

RESUMO

Hepatocellular carcinoma (HCC) genomic research has discovered actionable genetic changes that might guide treatment decisions and clinical trials. Nonetheless, due to a lack of large-scale multicenter clinical validation, these putative targets have not been converted into patient survival advantages. So, it's crucial to ascertain whether genetic analysis is clinically feasible, useful, and whether it can be advantageous for patients. We sequenced tumour tissue and blood samples (as normal controls) from 111 Chinese HCC patients at Qingdao University Hospital using the 508-gene panel and the 688-gene panel, respectively. Approximately 95% of patients had gene variations related to targeted treatment, with 50% having clinically actionable mutations that offered significant information for targeted therapy. Immune cell infiltration was enhanced in individuals with TP53 mutations but decreased in patients with CTNNB1 and KMT2D mutations. More notably, we discovered that SPEN, EPPK1, and BRCA2 mutations were related to decreased median overall survival, although MUC16 mutations were not. Furthermore, we found mutant MUC16 as an independent protective factor for the prognosis of HCC patients after curative hepatectomy. In conclusion, this study connects genetic abnormalities to clinical practice and potentially identifies individuals with poor prognoses who may benefit from targeted treatment or immunotherapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Mutação , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Masculino , Feminino , Prognóstico , Pessoa de Meia-Idade , Idoso , Adulto , Biomarcadores Tumorais/genética , Genômica/métodos , Proteína BRCA2/genética , Terapia de Alvo Molecular , Hepatectomia , Perfilação da Expressão Gênica , Proteína Supressora de Tumor p53/genética , Proteínas de Ligação a DNA , Proteínas de Neoplasias , beta Catenina
17.
Bioorg Med Chem ; 97: 117542, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38104495

RESUMO

Glutaminyl cyclase (QC) plays a crucial role in the early stages of Alzheimer's disease (AD), thus inhibition of QC may be a promising strategy for the treatment of early AD. Therefore, QC inhibitors with novel chemical scaffolds may contribute to the development of additional anti-AD agents. We conducted a virtual screening of 3 million compounds from the Chemdiv and Enamine databases, to discover potential scaffolds for QC inhibitors. Three scaffolds, 120974, 147706, and 141449, were selected from this structure-based virtual screening through a combination of pharmacophore modeling, a receptor-ligand pharmacophore model, and the GALAHAD model, and furtherly filtered by chelation with zinc ion and docking properties. Consequently, three compounds, 1, 2, and 3, were designed and synthesized based on these three scaffolds, respectively. The IC50 of compounds 1 and 3 against QC were 14.19 ± 4.21 and 4.34 ± 0.35 µM, respectively. Our results indicate that the new scaffolds selected using a virtual screening process exhibit potential as novel QC inhibitors.


Assuntos
Doença de Alzheimer , Aminoaciltransferases , Humanos , Aminoaciltransferases/antagonistas & inibidores , Aminoaciltransferases/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Simulação de Acoplamento Molecular
18.
Cereb Cortex ; 33(21): 10848-10857, 2023 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-37697910

RESUMO

Brian imaging-derived phenotypes (IDPs) have been suggested to be associated with ischemic stroke, but the causality between them remains unclear. In this bidirectional two-sample Mendelian randomization (MR) study, we explored the potential causal relationship between 461 imaging-derived phenotypes (n = 33,224, UK Biobank) and ischemic stroke (n = 34,217 cases/406,111 controls, Multiancestry Genome-Wide Association Study of Stroke). Forward MR analyses identified five IDPs associated with ischemic stroke, including mean diffusivity (MD) in the right superior fronto-occipital fasciculus (1.22 [95% CI, 1.11-1.34]), MD in the left superior fronto-occipital fasciculus (1.30 [1.17-1.44]), MD in the anterior limb of the right internal capsule (1.36 [1.22-1.51]), MD in the right anterior thalamic radiation (1.17 [1.09-1.26]), and MD in the right superior thalamic radiation (1.23 [1.11-1.35]). In the reverse MR analyses, ischemic stroke was identified to be associated with three IDPs, including high isotropic or free water volume fraction in the body of corpus callosum (beta, 0.189 [95% confidence interval, 0.107-0.271]), orientation dispersion index in the pontine crossing tract (0.175 [0.093-0.257]), and volume of the third ventricle (0.219 [0.138-0.301]). This bidirectional two-sample MR study suggested five predictors and three diagnostic markers for ischemic stroke at the brain-imaging level. Further studies are warranted to replicate our findings and clarify underlying mechanisms.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Análise da Randomização Mendeliana/métodos , Estudo de Associação Genômica Ampla , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , Neuroimagem
19.
Nutr Metab Cardiovasc Dis ; 34(3): 624-632, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38176958

RESUMO

BACKGROUND AND AIM: Observational studies have suggested a relationship between frailty and cardiovascular disease (CVD), but the causality is still uncertain. We used bidirectional Mendelian randomization (MR) design to investigate the potential causal associations between frailty and four main CVDs, including hypertension, myocardial infarction (MI), heart failure (HF), and atrial fibrillation (AF). METHODS AND RESULTS: Independent single-nucleotide polymorphisms for frailty index (FI) and CVDs (hypertension, MI, HF, and AF) were selected as genetic instruments based on European-descent genome-wide association studies (GWASs). Summary-level data for outcomes on FI (n = 175,226), hypertension (n = 463,010), MI (n = 171,875), HF (n = 977323), and AF (n = 1,030,836) was derived from five large-scale GWASs of European ancestry. We used the inverse-variance weighted (IVW) method to examine the bidirectional associations between FI and CVDs in the main analyses. In the IVW MR analyses, genetically determined high FI was significantly associated with increased risks of hypertension (odds ratio [OR] per 1-SD increase: 1.07 [95 % confidence interval, 1.05-1.08]), MI (OR per 1-SD increase: 1.74 [1.21-2.51]), HF (OR per 1-SD increase: 1.28 [1.10-1.48]), and AF (OR per 1-SD increase: 1.20 [1.08-1.33]). In addition, genetically determined hypertension (beta: 1.406 [1.225-1.587]), MI (beta: 0.045 [0.023-0.067]), HF (beta: 0.105 [0.066-0.143]) and AF (beta: 0.021 [0.012-0.031]) were significantly associated with high FI. These findings were robustly supported by a series of sensitivity analyses with different MR models. CONCLUSIONS: We found potential bidirectional causal associations between elevated FI and increased risks of CVD, suggesting mutual risk factors between frailty and CVD.


Assuntos
Fibrilação Atrial , Doenças Cardiovasculares , Fragilidade , Insuficiência Cardíaca , Hipertensão , Infarto do Miocárdio , Humanos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/genética , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Fragilidade/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Hipertensão/genética , Polimorfismo de Nucleotídeo Único
20.
J Nanobiotechnology ; 22(1): 547, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39238027

RESUMO

Rheumatoid arthritis (RA) involves chronic inflammation, oxidative stress, and complex immune cell interactions, leading to joint destruction. Traditional treatments are often limited by off-target effects and systemic toxicity. This study introduces a novel therapeutic approach using hyaluronic acid (HA)-conjugated, redox-responsive polyamino acid nanogels (HA-NG) to deliver tacrolimus (TAC) specifically to inflamed joints. The nanogels' disulfide bonds enable controlled TAC release in response to high intracellular glutathione (GSH) levels in activated macrophages, prevalent in RA-affected tissues. In vitro results demonstrated that HA-NG/TAC significantly reduced TAC toxicity to normal macrophages and showed high biocompatibility. In vivo, HA-NG/TAC accumulated more in inflamed joints compared to non-targeted NG/TAC, enhancing therapeutic efficacy and minimizing side effects. Therapeutic evaluation in collagen-induced arthritis (CIA) mice revealed HA-NG/TAC substantially reduced paw swelling, arthritis scores, synovial inflammation, and bone erosion while suppressing pro-inflammatory cytokine levels. These findings suggest that HA-NG/TAC represents a promising targeted drug delivery system for RA, offering potential for more effective and safer clinical applications.


Assuntos
Artrite Experimental , Artrite Reumatoide , Ácido Hialurônico , Nanogéis , Peptídeos , Tacrolimo , Animais , Ácido Hialurônico/química , Artrite Reumatoide/tratamento farmacológico , Camundongos , Tacrolimo/farmacologia , Tacrolimo/uso terapêutico , Tacrolimo/química , Tacrolimo/farmacocinética , Artrite Experimental/tratamento farmacológico , Peptídeos/química , Peptídeos/farmacologia , Nanogéis/química , Masculino , Células RAW 264.7 , Sistemas de Liberação de Medicamentos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos Endogâmicos DBA , Portadores de Fármacos/química , Humanos
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