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1.
EMBO J ; 42(6): e112094, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36727301

RESUMO

DNA-PKcs is a key regulator of DNA double-strand break repair. Apart from its canonical role in the DNA damage response, DNA-PKcs is involved in the cellular response to oxidative stress (OS), but its exact role remains unclear. Here, we report that DNA-PKcs-deficient human cells display depolarized mitochondria membrane potential (MMP) and reoriented metabolism, supporting a role for DNA-PKcs in oxidative phosphorylation (OXPHOS). DNA-PKcs directly interacts with mitochondria proteins ANT2 and VDAC2, and formation of the DNA-PKcs/ANT2/VDAC2 (DAV) complex supports optimal exchange of ADP and ATP across mitochondrial membranes to energize the cell via OXPHOS and to maintain MMP. Moreover, we demonstrate that the DAV complex temporarily dissociates in response to oxidative stress to attenuate ADP-ATP exchange, a rate-limiting step for OXPHOS. Finally, we found that dissociation of the DAV complex is mediated by phosphorylation of DNA-PKcs at its Thr2609 cluster by ATM kinase. Based on these findings, we propose that the coordination between the DAV complex and ATM serves as a novel oxidative stress checkpoint to decrease ROS production from mitochondrial OXPHOS and to hasten cellular recovery from OS.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ligação a DNA , Estresse Oxidativo , Humanos , Trifosfato de Adenosina/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , DNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Mitocôndrias/metabolismo , Fosforilação
2.
Hum Mol Genet ; 33(11): 958-968, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38453145

RESUMO

Type 1 diabetes (T1D) is an autoimmune disease caused by destruction of the pancreatic ß-cells. Genome-wide association (GWAS) and fine mapping studies have been conducted mainly in European ancestry (EUR) populations. We performed a multi-ancestry GWAS to identify SNPs and HLA alleles associated with T1D risk and age at onset. EUR families (N = 3223), and unrelated individuals of African (AFR, N = 891) and admixed (Hispanic/Latino) ancestry (AMR, N = 308) were genotyped using the Illumina HumanCoreExome BeadArray, with imputation to the TOPMed reference panel. The Multi-Ethnic HLA reference panel was utilized to impute HLA alleles and amino acid residues. Logistic mixed models (T1D risk) and frailty models (age at onset) were used for analysis. In GWAS meta-analysis, seven loci were associated with T1D risk at genome-wide significance: PTPN22, HLA-DQA1, IL2RA, RNLS, INS, IKZF4-RPS26-ERBB3, and SH2B3, with four associated with T1D age at onset (PTPN22, HLA-DQB1, INS, and ERBB3). AFR and AMR meta-analysis revealed NRP1 as associated with T1D risk and age at onset, although NRP1 variants were not associated in EUR ancestry. In contrast, the PTPN22 variant was significantly associated with risk only in EUR ancestry. HLA alleles and haplotypes most significantly associated with T1D risk in AFR and AMR ancestry differed from that seen in EUR ancestry; in addition, the HLA-DRB1*08:02-DQA1*04:01-DQB1*04:02 haplotype was 'protective' in AMR while HLA-DRB1*08:01-DQA1*04:01-DQB1*04:02 haplotype was 'risk' in EUR ancestry, differing only at HLA-DRB1*08. These results suggest that much larger sample sizes in non-EUR populations are required to capture novel loci associated with T1D risk.


Assuntos
Diabetes Mellitus Tipo 1 , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Humanos , Diabetes Mellitus Tipo 1/genética , Masculino , Feminino , População Branca/genética , Idade de Início , Alelos , Cadeias alfa de HLA-DQ/genética , População Negra/genética , Criança , Hispânico ou Latino/genética , Antígenos HLA/genética , Adolescente
3.
Am J Hum Genet ; 108(4): 564-582, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33713608

RESUMO

Although many loci have been associated with height in European ancestry populations, very few have been identified in African ancestry individuals. Furthermore, many of the known loci have yet to be generalized to and fine-mapped within a large-scale African ancestry sample. We performed sex-combined and sex-stratified meta-analyses in up to 52,764 individuals with height and genome-wide genotyping data from the African Ancestry Anthropometry Genetics Consortium (AAAGC). We additionally combined our African ancestry meta-analysis results with published European genome-wide association study (GWAS) data. In the African ancestry analyses, we identified three novel loci (SLC4A3, NCOA2, ECD/FAM149B1) in sex-combined results and two loci (CRB1, KLF6) in women only. In the African plus European sex-combined GWAS, we identified an additional three novel loci (RCCD1, G6PC3, CEP95) which were equally driven by AAAGC and European results. Among 39 genome-wide significant signals at known loci, conditioning index SNPs from European studies identified 20 secondary signals. Two of the 20 new secondary signals and none of the 8 novel loci had minor allele frequencies (MAF) < 5%. Of 802 known European height signals, 643 displayed directionally consistent associations with height, of which 205 were nominally significant (p < 0.05) in the African ancestry sex-combined sample. Furthermore, 148 of 241 loci contained ≤20 variants in the credible sets that jointly account for 99% of the posterior probability of driving the associations. In summary, trans-ethnic meta-analyses revealed novel signals and further improved fine-mapping of putative causal variants in loci shared between African and European ancestry populations.


Assuntos
População Negra/genética , Estatura/genética , Estudo de Associação Genômica Ampla , África/etnologia , Negro ou Afro-Americano/genética , Europa (Continente)/etnologia , Feminino , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética
4.
Chemistry ; 30(51): e202401553, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-38937940

RESUMO

Copper iodide organic-inorganic hybrid materials have been favored by many researchers in the field of solid-state lighting (SSL) due to their structural diversity and optical adjustability. In this paper, three isomeric copper iodide cluster hybrid materials, Cu4I6(L)2(1), Cu5I4.5Cl2.5(L)2(2) and Cu5I7(L)2) (3) (L=1-(4-methylpyrimidin-2-yl)-1,4-diazabicyclo[2.2.2]octan-1-ium), were achieved by adjusting the reaction conditions. The crystal color transit from green, yellow to orange and the internal quantum yield (IQY) increase from 57 %-88 %. All three complexes have good thermal stability, good solution processability, and high quantum yield. And origin and mechanism of luminescence of complexes were further studied. This study can provide ideas and theoretical basis for the regulation of cuprous iodide cluster luminescent materials.

5.
Int J Mol Sci ; 25(4)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38397002

RESUMO

Ferroptosis, a unique form of programmed cell death trigged by lipid peroxidation and iron accumulation, has been implicated in embryonic erythropoiesis and aging. Our previous research demonstrated that lysophosphatidic acid receptor 3 (LPA3) activation mitigated oxidative stress in progeria cells and accelerated the recovery of acute anemia in mice. Given that both processes involve iron metabolism, we hypothesized that LPA3 activation might mediate cellular ferroptosis. In this study, we used an LPA3 agonist, 1-Oleoyl-2-O-methyl-rac-glycerophosphothionate (OMPT), to activate LPA3 and examine its effects on the ferroptosis process. OMPT treatment elevated anti-ferroptosis gene protein expression, including solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), heme oxygenase-1 (HO-1), and ferritin heavy chain (FTH1), in erastin-induced cells. Furthermore, OMPT reduced lipid peroxidation and intracellular ferrous iron accumulation, as evidenced by C11 BODIPY™ 581/591 Lipid Peroxidation Sensor and FerroOrange staining. These observations were validated by applying LPAR3 siRNA in the experiments mentioned above. In addition, the protein expression level of nuclear factor erythroid 2-related factor (NRF2), a key regulator of oxidative stress, was also enhanced in OMPT-treated cells. Lastly, we verified that LPA3 plays a critical role in erastin-induced ferroptotic human erythroleukemia K562 cells. OMPT rescued the erythropoiesis defect caused by erastin in K562 cells based on a Gly A promoter luciferase assay. Taken together, our findings suggest that LPA3 activation inhibits cell ferroptosis by suppressing lipid oxidation and iron accumulation, indicating that ferroptosis could potentially serve as a link among LPA3, erythropoiesis, and aging.


Assuntos
Ferroptose , Receptores de Ácidos Lisofosfatídicos , Camundongos , Animais , Humanos , Receptores de Ácidos Lisofosfatídicos/genética , Receptores de Ácidos Lisofosfatídicos/metabolismo , Apoptose , Estresse Oxidativo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Ferro/metabolismo
6.
Cardiovasc Diabetol ; 21(1): 118, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35765074

RESUMO

BACKGROUND: Although a few meta-analyses were conducted to compare the risk of incident atrial fibrillation (AF) between sodium-glucose cotransporter-2 inhibitor (SGLT2i), glucagon-like peptide-1 receptor agonists (GLP-1RA), and other anti-hyperglycemic agents using indirect or direct comparison, the above analyses showed conflicting results with each other. We aimed to evaluate the risk of new-onset AF associated with the use of SGLT2i, GLP-1RA, and dipeptidyl peptidase-4 inhibitor (DPP4i) among a large longitudinal cohort of diabetic patients. METHODS: In this nationwide retrospective cohort study based on the Taiwan National Health Insurance Research Database, a total of 344,893, 44,370, and 393,100 consecutive patients with type 2 diabetes without preexisting AF receiving GLP-1RA, SGLT2i, and DPP4i, respectively, were enrolled from May 1, 2016, to December 31, 2019. We used 1:1 propensity score matching (PSM) to balance covariates across paired study groups. Patients were followed from the drug index date until the occurrence of AF, death, discontinuation of the index drug, or the end of the study period (December 31, 2020), whichever occurred first. RESULTS: After PSM, there were 245,442, 43,682, and 39,190 paired cohorts of SGLT2i-DPP4i, SGLT2i-GLP-1RA, and GLP-1RA-DPP4i, respectively. SGLT2i treatment was associated with lower risk of new-onset AF in participants with type 2 diabetes compared with either DPP4i [hazard ratio (HR):0.90; 95% confidential interval (CI) 0.84-0.96; P = 0.0028] or GLP-1RA [HR 0.74; 95% CI 0.63-0.88; P = 0.0007] treatment after PSM. There was no difference in the risk of incident AF between GLP-1RA and DPP4i users [HR 1.01; 95% CI 0.86-1.19; P = 0.8980]. The above findings persisted among several important subgroups. Dapagliflozin was specifically associated with a lower risk of new-onset AF compared with DPP4i (P interaction = 0.02). CONCLUSIONS: Compared with DPP4i, SGLT2i but not GLP-1RA was associated with a lower risk of incident AF in patients with type 2 diabetes.


Assuntos
Fibrilação Atrial , Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Inibidores do Transportador 2 de Sódio-Glicose , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/epidemiologia , Estudos de Coortes , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Dipeptidil Peptidases e Tripeptidil Peptidases/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Humanos , Hipoglicemiantes/efeitos adversos , Estudos Retrospectivos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos
7.
Am J Physiol Cell Physiol ; 320(4): C509-C519, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33406026

RESUMO

Lysophosphatidic acid (LPA) is one of the lipids identified to be involved in stem cell differentiation. It exerts various functions through activation of G protein-coupled lysophosphatidic acid receptors (LPARs). In previous studies, we have demonstrated that activation of LPA receptor 3 (LPA3) promotes erythropoiesis of human hematopoietic stem cells (HSCs) and zebrafish using molecular and pharmacological approaches. Our results show that treatment with lysophosphatidic acid receptor 2 (LPA2) agonist suppressed erythropoiesis, whereas activation of LPA3 by 1-oleoyl-2-methyl-sn-glycero-3-phosphothionate (2S-OMPT) promoted it, both in vitro and in vivo. Furthermore, we have demonstrated the inhibitory role of LPA3 during megakaryopoiesis. However, the mechanism underlying these observations remains elusive. In the present study, we suggest that the expression pattern of LPARs may be correlated with the transcriptional factors GATA-1 and GATA-2 at different stages of myeloid progenitors. We determined that manipulation of GATA factors affected the expression levels of LPA2 and LPA3 in K562 leukemia cells. Using luciferase assays, we demonstrate that the promoter regions of LPAR2 and LPAR3 genes were regulated by these GATA factors in HEK293T cells. Mutation of GATA-binding sites in these regions abrogated luciferase activity, suggesting that LPA2 and LPA3 are regulated by GATA factors. Moreover, physical interaction between GATA factors and the promoter region of LPAR genes was verified in K562 cells using chromatin immunoprecipitation (ChIP) studies. Taken together, our results suggest that balance between LPA2 and LPA3 expression, which may be determined by GATA factors, is a regulatory switch for lineage commitment in myeloid progenitors. The expression-level balance of LPA receptor subtypes represents a novel mechanism regulating erythropoiesis and megakaryopoiesis.


Assuntos
Linhagem da Célula , Hematopoese , Células-Tronco Hematopoéticas/metabolismo , Receptores de Ácidos Lisofosfatídicos/metabolismo , Transcrição Gênica , Sítios de Ligação , Eritropoese , Fator de Transcrição GATA1/genética , Fator de Transcrição GATA1/metabolismo , Fator de Transcrição GATA2/genética , Fator de Transcrição GATA2/metabolismo , Células HEK293 , Humanos , Células K562 , Regiões Promotoras Genéticas , Receptores de Ácidos Lisofosfatídicos/genética , Transdução de Sinais , Trombopoese
8.
Am J Hum Genet ; 103(5): 691-706, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30388399

RESUMO

C-reactive protein (CRP) is a sensitive biomarker of chronic low-grade inflammation and is associated with multiple complex diseases. The genetic determinants of chronic inflammation remain largely unknown, and the causal role of CRP in several clinical outcomes is debated. We performed two genome-wide association studies (GWASs), on HapMap and 1000 Genomes imputed data, of circulating amounts of CRP by using data from 88 studies comprising 204,402 European individuals. Additionally, we performed in silico functional analyses and Mendelian randomization analyses with several clinical outcomes. The GWAS meta-analyses of CRP revealed 58 distinct genetic loci (p < 5 × 10-8). After adjustment for body mass index in the regression analysis, the associations at all except three loci remained. The lead variants at the distinct loci explained up to 7.0% of the variance in circulating amounts of CRP. We identified 66 gene sets that were organized in two substantially correlated clusters, one mainly composed of immune pathways and the other characterized by metabolic pathways in the liver. Mendelian randomization analyses revealed a causal protective effect of CRP on schizophrenia and a risk-increasing effect on bipolar disorder. Our findings provide further insights into the biology of inflammation and could lead to interventions for treating inflammation and its clinical consequences.


Assuntos
Loci Gênicos/genética , Inflamação/genética , Redes e Vias Metabólicas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Transtorno Bipolar/genética , Transtorno Bipolar/metabolismo , Índice de Massa Corporal , Proteína C-Reativa/genética , Criança , Feminino , Estudo de Associação Genômica Ampla/métodos , Humanos , Inflamação/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Análise da Randomização Mendeliana/métodos , Pessoa de Meia-Idade , Esquizofrenia/genética , Esquizofrenia/metabolismo , Adulto Jovem
9.
Diabet Med ; 38(8): e14545, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33605492

RESUMO

AIMS: We aimed to identify long-term HbA1c trajectories and examine associated characteristics in an observational, childhood-onset (<17 years) type 1 diabetes cohort. METHODS: Data are from the Epidemiology of Diabetes Complications study, comprising 405 participants with ≥2 of seven possible HbA1c measurements over follow-up (1988-2013) and available DNA (baseline mean diabetes duration 21 years, 53% men). HbA1c trajectories were estimated using latent class growth models. Baseline and change in participant characteristics were compared across trajectories. RESULTS: Five HbA1c trajectories were identified: low (51%), intermediate stable (22%), improved (19%), high stable (6%), and worsened (2%; not included in analyses). Age, diabetes duration, diabetes onset age, and sex did not differ across trajectories. Characteristics did not differ significantly between intermediate stable and low trajectories at baseline, though albumin excretion rate (AER, p = 0.0002) and estimated glomerular filtration rate (eGFR, p = 0.001) worsened slightly more in intermediate stable over time. Improved and high stable trajectories had higher baseline LDL-c (p = 0.002 and 0.003, respectively). Improved trajectory increased median self-monitoring of blood glucose from <1 to 3.5 times/day (p < 0.0001) and had larger LDL-c improvement (p = 0.004) but greater worsening of AER (p < 0.0001) and eGFR (p < 0.0001) than low. The A allele of rs12970134 (near MC4R) was associated with improved (p = 0.0003) or high stable (p = 0.001) HbA1c trajectory, both patterns with high baseline HbA1c. CONCLUSIONS: Long-term HbA1c trajectories were primarily associated with modifiable factors in this type 1 diabetes cohort. The intermediate stable pattern had a risk factor profile that suggests some protection against adverse metabolic effects of chronic hyperglycaemia, warranting further study.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Previsões , Hemoglobinas Glicadas/metabolismo , Adulto , Feminino , Seguimentos , Controle Glicêmico , Humanos , Masculino , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
10.
Am J Phys Anthropol ; 175(4): 905-919, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34008864

RESUMO

OBJECTIVES: Gullah African Americans are descendants of formerly enslaved Africans living in the Sea Islands along the coast of the southeastern U.S., from North Carolina to Florida. Their relatively high numbers and geographic isolation were conducive to the development and preservation of a unique culture that retains deep African features. Although historical evidence supports a West-Central African ancestry for the Gullah, linguistic and cultural evidence of a connection to Sierra Leone has led to the suggestion of this country/region as their ancestral home. This study sought to elucidate the genetic structure and ancestry of the Gullah. MATERIALS AND METHODS: We leveraged whole-genome genotype data from Gullah, African Americans from Jackson, Mississippi, African populations from Sierra Leone, and population reference panels from Africa and Europe to infer population structure, ancestry proportions, and global estimates of admixture. RESULTS: Relative to non-Gullah African Americans from the Southeast US, the Gullah exhibited higher mean African ancestry, lower European admixture, a similarly small Native American contribution, and increased male-biased European admixture. A slightly tighter bottleneck in the Gullah 13 generations ago suggests a largely shared demographic history with non-Gullah African Americans. Despite a slightly higher relatedness to populations from Sierra Leone, our data demonstrate that the Gullah are genetically related to many West African populations. DISCUSSION: This study confirms that subtle differences in African American population structure exist at finer regional levels. Such observations can help to inform medical genetics research in African Americans, and guide the interpretation of genetic data used by African Americans seeking to explore ancestral identities.


Assuntos
População Negra , Negro ou Afro-Americano , África , Negro ou Afro-Americano/genética , População Negra/genética , Europa (Continente) , Genótipo , Humanos , Masculino
11.
Stroke ; 51(8): 2454-2463, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32693751

RESUMO

BACKGROUND AND PURPOSE: Stroke is a complex disease with multiple genetic and environmental risk factors. Blacks endure a nearly 2-fold greater risk of stroke and are 2× to 3× more likely to die from stroke than European Americans. METHODS: The COMPASS (Consortium of Minority Population Genome-Wide Association Studies of Stroke) has conducted a genome-wide association meta-analysis of stroke in >22 000 individuals of African ancestry (3734 cases, 18 317 controls) from 13 cohorts. RESULTS: In meta-analyses, we identified one single nucleotide polymorphism (rs55931441) near the HNF1A gene that reached genome-wide significance (P=4.62×10-8) and an additional 29 variants with suggestive evidence of association (P<1×10-6), representing 24 unique loci. For validation, a look-up analysis for a 100 kb region flanking the COMPASS single nucleotide polymorphism was performed in SiGN (Stroke Genetics Network) Europeans, SiGN Hispanics, and METASTROKE (Europeans). Using a stringent Bonferroni correction P value of 2.08×10-3 (0.05/24 unique loci), we were able to validate associations at the HNF1A locus in both SiGN (P=8.18×10-4) and METASTROKE (P=1.72×10-3) European populations. Overall, 16 of 24 loci showed evidence for validation across multiple populations. Previous studies have reported associations between variants in the HNF1A gene and lipids, C-reactive protein, and risk of coronary artery disease and stroke. Suggestive associations with variants in the SFXN4 and TMEM108 genes represent potential novel ischemic stroke loci. CONCLUSIONS: These findings represent the most thorough investigation of genetic determinants of stroke in individuals of African descent, to date.


Assuntos
Negro ou Afro-Americano/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Polimorfismo de Nucleotídeo Único/genética , Acidente Vascular Cerebral/genética , Negro ou Afro-Americano/etnologia , Estudos de Coortes , Predisposição Genética para Doença/etnologia , Humanos , Acidente Vascular Cerebral/etnologia
12.
Microb Pathog ; 148: 104414, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32771657

RESUMO

Biofilm formation and virulence factor secretion in opportunistic pathogen Pseudomonas aeruginosa are essential for establishment of chronic and recurrent infection, which are regulated by quorum sensing (QS) system. In this study, a set of cajaninstilbene acid analogues were designed and synthesized, and their abilities to inhibit QS and biofilm formation were investigated. Among all the compounds, compounds 3g, 3m and 3o showed potent anti-biofilm activity, especially 3o exhibited promising biofilm inhibitory activity with biofilm inhibition ratio of 49.50 ± 1.35% at 50 µM. Three lacZ reporter strains were constructed to identify the effects of compound 3o on different QS systems. Compound 3o showed the suppression on the expression of lasB-lacZ and pqsA-lacZ as well as on the production of their corresponding virulence factors. Therefore, compound 3o is expected to be generated as a lead compound with inhibition of biofilm formation and QS of Pseudomonas aeruginosa.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum , Salicilatos/farmacologia , Estilbenos/farmacologia , Proteínas de Bactérias/genética , Percepção de Quorum/efeitos dos fármacos , Fatores de Virulência
13.
Nanotechnology ; 31(12): 125706, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31770738

RESUMO

Inspired by natural photosynthesis, artificial heterojunction photocatalysts have been extensively studied. Herein, a novel ternary graphitic carbon nitride/platinum/bismuth vanadate (g-C3N4/Pt/BiVO4) photocatalytic system was successfully synthesized, where Pt/BiVO4 nanosheet is anchored on the surface of layered g-C3N4, as evidenced by structural observations. Ultraviolet photoelectron spectroscopy and ultraviolet-visible diffuse reflectance spectroscopy are carried out to identify the position of the conduction band and valence band. A Z-scheme is used to interpret the superior photocatalytic performance of g-C3N4/Pt/BiVO4 and further verified by the capture of free radicals and terephthalic acid photoluminescence experiments. Compared with the g-C3N4/BiVO4 binary system, the Z-scheme g-C3N4/Pt/BiVO4 photocatalyst not only possesses enhanced carrier separation efficiency but also maintains sufficient redox properties, thus inducing superior photocatalytic activity. More importantly, the novel Z-scheme photocatalyst exhibits excellent recycle stability, which could provide inspiration for the rational design of efficient and practical photocatalysts for environmental pollution treatment. The ternary photocatalyst also exhibits significantly enhanced visible-light photocatalytic hydrogen production performance.

14.
PLoS Genet ; 13(4): e1006719, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28430825

RESUMO

Genome-wide association studies (GWAS) have identified >300 loci associated with measures of adiposity including body mass index (BMI) and waist-to-hip ratio (adjusted for BMI, WHRadjBMI), but few have been identified through screening of the African ancestry genomes. We performed large scale meta-analyses and replications in up to 52,895 individuals for BMI and up to 23,095 individuals for WHRadjBMI from the African Ancestry Anthropometry Genetics Consortium (AAAGC) using 1000 Genomes phase 1 imputed GWAS to improve coverage of both common and low frequency variants in the low linkage disequilibrium African ancestry genomes. In the sex-combined analyses, we identified one novel locus (TCF7L2/HABP2) for WHRadjBMI and eight previously established loci at P < 5×10-8: seven for BMI, and one for WHRadjBMI in African ancestry individuals. An additional novel locus (SPRYD7/DLEU2) was identified for WHRadjBMI when combined with European GWAS. In the sex-stratified analyses, we identified three novel loci for BMI (INTS10/LPL and MLC1 in men, IRX4/IRX2 in women) and four for WHRadjBMI (SSX2IP, CASC8, PDE3B and ZDHHC1/HSD11B2 in women) in individuals of African ancestry or both African and European ancestry. For four of the novel variants, the minor allele frequency was low (<5%). In the trans-ethnic fine mapping of 47 BMI loci and 27 WHRadjBMI loci that were locus-wide significant (P < 0.05 adjusted for effective number of variants per locus) from the African ancestry sex-combined and sex-stratified analyses, 26 BMI loci and 17 WHRadjBMI loci contained ≤ 20 variants in the credible sets that jointly account for 99% posterior probability of driving the associations. The lead variants in 13 of these loci had a high probability of being causal. As compared to our previous HapMap imputed GWAS for BMI and WHRadjBMI including up to 71,412 and 27,350 African ancestry individuals, respectively, our results suggest that 1000 Genomes imputation showed modest improvement in identifying GWAS loci including low frequency variants. Trans-ethnic meta-analyses further improved fine mapping of putative causal variants in loci shared between the African and European ancestry populations.


Assuntos
Adiposidade/genética , Obesidade/genética , Serina Endopeptidases/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Antropometria , População Negra/genética , Índice de Massa Corporal , Mapeamento Cromossômico , Feminino , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Desequilíbrio de Ligação , Masculino , Obesidade/patologia , Polimorfismo de Nucleotídeo Único , Relação Cintura-Quadril , População Branca/genética
15.
J Am Soc Nephrol ; 30(10): 2000-2016, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31537649

RESUMO

BACKGROUND: Although diabetic kidney disease demonstrates both familial clustering and single nucleotide polymorphism heritability, the specific genetic factors influencing risk remain largely unknown. METHODS: To identify genetic variants predisposing to diabetic kidney disease, we performed genome-wide association study (GWAS) analyses. Through collaboration with the Diabetes Nephropathy Collaborative Research Initiative, we assembled a large collection of type 1 diabetes cohorts with harmonized diabetic kidney disease phenotypes. We used a spectrum of ten diabetic kidney disease definitions based on albuminuria and renal function. RESULTS: Our GWAS meta-analysis included association results for up to 19,406 individuals of European descent with type 1 diabetes. We identified 16 genome-wide significant risk loci. The variant with the strongest association (rs55703767) is a common missense mutation in the collagen type IV alpha 3 chain (COL4A3) gene, which encodes a major structural component of the glomerular basement membrane (GBM). Mutations in COL4A3 are implicated in heritable nephropathies, including the progressive inherited nephropathy Alport syndrome. The rs55703767 minor allele (Asp326Tyr) is protective against several definitions of diabetic kidney disease, including albuminuria and ESKD, and demonstrated a significant association with GBM width; protective allele carriers had thinner GBM before any signs of kidney disease, and its effect was dependent on glycemia. Three other loci are in or near genes with known or suggestive involvement in this condition (BMP7) or renal biology (COLEC11 and DDR1). CONCLUSIONS: The 16 diabetic kidney disease-associated loci may provide novel insights into the pathogenesis of this condition and help identify potential biologic targets for prevention and treatment.


Assuntos
Autoantígenos/genética , Colágeno Tipo IV/genética , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/genética , Estudo de Associação Genômica Ampla , Membrana Basal Glomerular , Mutação , Estudos de Coortes , Feminino , Humanos , Masculino
16.
Am J Hum Genet ; 99(1): 56-75, 2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27321945

RESUMO

Knowledge of the genetic basis of the type 2 diabetes (T2D)-related quantitative traits fasting glucose (FG) and insulin (FI) in African ancestry (AA) individuals has been limited. In non-diabetic subjects of AA (n = 20,209) and European ancestry (EA; n = 57,292), we performed trans-ethnic (AA+EA) fine-mapping of 54 established EA FG or FI loci with detailed functional annotation, assessed their relevance in AA individuals, and sought previously undescribed loci through trans-ethnic (AA+EA) meta-analysis. We narrowed credible sets of variants driving association signals for 22/54 EA-associated loci; 18/22 credible sets overlapped with active islet-specific enhancers or transcription factor (TF) binding sites, and 21/22 contained at least one TF motif. Of the 54 EA-associated loci, 23 were shared between EA and AA. Replication with an additional 10,096 AA individuals identified two previously undescribed FI loci, chrX FAM133A (rs213676) and chr5 PELO (rs6450057). Trans-ethnic analyses with regulatory annotation illuminate the genetic architecture of glycemic traits and suggest gene regulation as a target to advance precision medicine for T2D. Our approach to utilize state-of-the-art functional annotation and implement trans-ethnic association analysis for discovery and fine-mapping offers a framework for further follow-up and characterization of GWAS signals of complex trait loci.


Assuntos
Glicemia/genética , Diabetes Mellitus Tipo 2/genética , Etnicidade/genética , Jejum/metabolismo , Insulina/metabolismo , Grupos Raciais/genética , Povo Asiático/genética , População Negra/genética , Elementos Facilitadores Genéticos/genética , Feminino , Frequência do Gene/genética , Estudo de Associação Genômica Ampla , Humanos , Resistência à Insulina/genética , Íntrons/genética , Ilhotas Pancreáticas/metabolismo , Masculino , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Fatores de Transcrição/metabolismo , População Branca/genética
17.
Bioorg Med Chem Lett ; 29(5): 749-754, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30630718

RESUMO

Signal molecules are stimulators of multiple quroum-sensing virulence and biofilm formation. Small molecule analogues have been suspected as a potent inhibitor in therapeutic strategy. Herein, we synthesized a series of small molecule compounds from the 2, 8-bit derivatives of quinoline by Suzuki coupling reaction. We found that these compounds have the biofilm inhibitory effect in normal condition instead of phosphate limitation state. Furthermore, lacZ reporter strain assay and rhamnolipids as well as pyocyanin experiments showed that these compounds did not affect las and pqs system but reduced the expression of rhl. All these results suggest that quinoline derivatives can be treated as potent inhibitors against biofilm and reduce virulence through the rhl system. This research will be useful in designing new quorum sensing inhibitors to attenuate the infection of bacteria.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Quinolinas/farmacologia , Virulência/efeitos dos fármacos , Óperon Lac , Pseudomonas aeruginosa/patogenicidade , Quinolinas/química , Percepção de Quorum
18.
J Nat Prod ; 82(12): 3227-3232, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31747283

RESUMO

Five new matrine-type alkaloid dimers, alopecuroides A-E, were isolated from the aerial parts of Sophora alopecuroides. Alopecuroides A and B represent the first dimeric matrine-type alkaloids possessing a cyano group and an epoxy moiety. Alopecuroides C and D are dimeric matrine-type alkaloids connected via C-2-C-9' and C-10-C-3' bonds, respectively. The chemical structures of alopecuroides A-E were elucidated by spectroscopic methods combined with single-crystal X-ray diffraction analysis. The anti-inflammatory effects of alopecuroides A-E were evaluated, and alopecuroide B exhibited the most significant activity, better than that of matrine, the representative compound from S. alopecuroides.


Assuntos
Alcaloides/química , Componentes Aéreos da Planta/química , Quinolizinas/química , Sophora/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Cristalografia por Raios X , Dimerização , Camundongos , Estrutura Molecular , Células RAW 264.7 , Análise Espectral/métodos , Matrinas
19.
Drug Dev Res ; 80(6): 750-757, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31169945

RESUMO

The prevalence of multidrug resistance among clinically significant bacterial pathogens underlines a critical need for the development of new classes of antibacterial agents with novel structural scaffolds. Cajaninstilbene acid (CSA), which is isolated from pigeonpea leaves, has shown potent antibacterial activity. In this study, a series of 2-hydroxyl-4-methoxyl-3-(3-methylbut-2-en-1-yl)-6-(4-phenylbenzoylamino)benzoic acid derivatives derived from CSA were designed and synthesized, and their antibacterial activities were evaluated. Several synthesized compounds exhibit better antibacterial activity than CSA against Staphylococcus aureus, Staphylococcus epidermidis, and two strains of methicillin-resistant S. aureus. Meanwhile, the results of 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide assays illustrate the good selectivity between bacteria and normal cells of the most active compounds 6u and 6v. Furthermore, well combinations with bacterial RNA polymerase of 6u arising from docking study imply the possible mechanism of antibacterial activity of these synthetic compounds.


Assuntos
Antibacterianos , Benzoatos , Salicilatos , Estilbenos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Benzoatos/química , Benzoatos/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Testes de Sensibilidade Microbiana , Salicilatos/química , Salicilatos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Estilbenos/química , Estilbenos/farmacologia
20.
Int J Mol Sci ; 20(7)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30987025

RESUMO

BACKGROUND: S1P has been shown to improve the endothelialization of decellularized vascular grafts in vitro. Here, we evaluated the potential of tissue-engineered vascular grafts (TEVGs) constructed by ECs and S1P on decellularized vascular scaffolds in a rat model. METHODS: Rat aorta was decellularized mainly by 0.1% SDS and characterized by histology. Rat ECs, were seeded onto decellularized scaffolds, and the viability of the ECs was evaluated by biochemical assays. Then, we investigated the in vivo patency rate and endothelialization for five groups of decellularized vascular grafts (each n = 6) in a rat abdominal aorta model for 14 days. The five groups included (1) rat allogenic aorta (RAA); (2) decellularized RAA (DRAA); (3) DRAA with S1P (DRAA/S1P); (4) DRAA with EC recellularization (DRAA/EC); and (5) DRAA with S1P and EC recellularization (DRAA/EC/S1P). RESULTS: In vitro, ECs were identified by the uptake of Dil-Ac-LDL. S1P enhanced the expression of syndecan-1 on ECs and supported the proliferation of ECs on decellularized vascular grafts. In vivo, RAA and DRAA/EC/S1P both had 100% patency without thrombus formation within 14 days. Better endothelialization, more wall structure maintenance and less inflammation were noted in the DRAA/EC/S1P group. In contrast, there was thrombus formation in the DRAA, DRAA/S1P and DRAA/EC groups. CONCLUSION: S1P could inhibit thrombus formation to improve the patency rate of EC-covered decellularized vascular grafts in vivo and may play an important role in the construction of TEVGs.


Assuntos
Prótese Vascular , Células Endoteliais/metabolismo , Lisofosfolipídeos/metabolismo , Esfingosina/análogos & derivados , Grau de Desobstrução Vascular , Animais , Aorta/transplante , Implante de Prótese Vascular , Proliferação de Células , Forma Celular , Feminino , Macrófagos/metabolismo , Ratos Sprague-Dawley , Esfingosina/metabolismo , Análise de Sobrevida , Sindecana-1/metabolismo
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