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1.
JCI Insight ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833310

RESUMO

Patients with autoimmune diseases are at higher risk for severe infection due to their underlying disease and immunosuppressive treatments. In this real-world observational study of 463 autoimmune subjects, we examined risk factors for poor B and T cell responses to SARS-CoV-2 vaccination. We show a high frequency of inadequate anti-spike IgG responses to vaccination and boosting in the autoimmune population but minimal suppression of T cell responses. Low IgG responses in B cell-depleted multiple sclerosis (MS) subjects were associated with higher CD8 T cell responses. By contrast, subjects taking mycophenolate mofetil exhibited concordant suppression of B and T cell responses. Treatments with highest risk for low IgG anti-spike response included B cell depletion within the last year, fingolimod, and combination treatment with mycophenolate mofetil (MMF) and belimumab. Our data show that the mRNA-1273 (Moderna) vaccine, is the most effective vaccine in the autoimmune population. There was minimal induction of either disease flares or autoantibodies by vaccination and no significant effect of pre-existing anti-type I interferon antibodies on either vaccine response or breakthrough infections. The low frequency of breakthrough infections and lack of SARS-CoV-2-related deaths suggest that T cell immunity contributes to protection in autoimmune disease.

2.
medRxiv ; 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38370763

RESUMO

Importance: Wrist-worn activity monitors provide biomarkers of health by non-obtrusively measuring the timing and amount of rest and physical activity (rest-activity rhythms, RARs). The morphology and robustness of RARs vary by age, gender, and sociodemographic factors, and are perturbed in various chronic illnesses. However, these are cross-sectionally derived associations from recordings lasting 4-10 days, providing little insights into how RARs vary with time. Objective: To describe how RAR parameters can vary or evolve with time (~months). Design Setting and Participants: 48 very long actograms ("VLAs", ≥90 days in duration) were identified from subjects enrolled in the STAGES (Stanford Technology, Analytics and Genomics in Sleep) study, a prospective cross-sectional, multi-site assessment of individuals > 13 years of age that required diagnostic polysomnography to address a sleep complaint. A single 3-year long VLA (author GD) is also described. Exposures/Intervention: None planned. Main Outcomes and Measures: For each VLA, we assessed the following parameters in 14-day windows: circadian/ultradian spectrum, pseudo-F statistic ("F"), cosinor amplitude, intradaily variability, interdaily stability, acrophase and estimates of "sleep" and non-wearing. Results: Included STAGES subjects (n = 48, 30 female) had a median age of 51, BMI of 29.4kg/m2, Epworth Sleepiness Scale score (ESS) of 10/24 and a median recording duration of 120 days. We observed marked within-subject undulations in all six RAR parameters, with many subjects displaying ultradian rhythms of activity that waxed and waned in intensity. When appraised at the group level (nomothetic), averaged RAR parameters remained remarkably stable over a ~4 month recording period. Cohort-level deficits in average RAR robustness associated with unemployment or high BMI (>29.4) also remained stable over time. Conclusions and Relevance: Through an exemplary set of months-long wrist actigraphy recordings, this study quantitatively depicts the longitudinal stability and dynamic range of human rest-activity rhythms. We propose that continuous and long-term actigraphy may have broad potential as a holistic, transdiagnostic and ecologically valid monitoring biomarker of changes in chronobiological health. Prospective recordings from willing subjects will be necessary to precisely define contexts of use.

3.
Mol Cell ; 83(22): 4062-4077.e5, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37977118

RESUMO

Abnormal increases in cell size are associated with senescence and cell cycle exit. The mechanisms by which overgrowth primes cells to withdraw from the cell cycle remain unknown. We address this question using CDK4/6 inhibitors, which arrest cells in G0/G1 and are licensed to treat advanced HR+/HER2- breast cancer. We demonstrate that CDK4/6-inhibited cells overgrow during G0/G1, causing p38/p53/p21-dependent cell cycle withdrawal. Cell cycle withdrawal is triggered by biphasic p21 induction. The first p21 wave is caused by osmotic stress, leading to p38- and size-dependent accumulation of p21. CDK4/6 inhibitor washout results in some cells entering S-phase. Overgrown cells experience replication stress, resulting in a second p21 wave that promotes cell cycle withdrawal from G2 or the subsequent G1. We propose that the levels of p21 integrate signals from overgrowth-triggered stresses to determine cell fate. This model explains how hypertrophy can drive senescence and why CDK4/6 inhibitors have long-lasting effects in patients.


Assuntos
Proteína Supressora de Tumor p53 , Humanos , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ciclo Celular , Divisão Celular , Proteína Supressora de Tumor p53/genética , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo
4.
Chem Commun (Camb) ; 59(31): 4640-4643, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-36988099

RESUMO

Focusing on a reliable supramolecular synthon approach, novel molecular salts of the antihypertensive medication ketanserin (KTS) with aromatic carboxylic acid derivatives (benzoic acid (BA), 2-hydroxybenzoic acid (2-HBA), and 2,5-dihydroxybenzoic acid (2,5-DHBA)) are reported. Binary salts of KTS with the respective salt former were obtained via solvent-assisted grinding followed by solution crystallization. Salt production was confirmed through crystal structure investigations that revealed proton transfer from the carboxylic acid group of the salt former to the piperidine nitrogen atom of KTS. A rigorous investigation of the crystal packing of novel binary salts of KTS inspired the construction of ternary adducts, and a ternary crystalline product was subsequently identified using milrinone (MLN), another cardiotonic drug. According to our knowledge, this is the first instance of a dual-drug ternary co-crystal combining both antihypertensive drugs. In order to evaluate the impacts of co-crystallization on the in vitro release behaviour of binary and ternary adducts, solubility tests for the cocrystal were carried out under a variety of physiological pH conditions. The results indicate that, in contrast to the parent drug and binary adducts, the solubility rate of the ternary adducts is significantly increased. Finally, the stability of the synthesised adduct was evaluated under a range of conditions, including temperature (40 ± 1 °C), humidity (90% ± 5% RH, 25 °C) and various solvents media, and it was established that they have good stability. We anticipate that the present findings will work with a wide range of medication combinations, providing a potential new approach to create multi-drug systems for cardiovascular disease.


Assuntos
Anti-Hipertensivos , Sais , Anti-Hipertensivos/química , Ketanserina , Sais/química , Solubilidade , Cristalização , Solventes/química
5.
Cells ; 8(10)2019 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615089

RESUMO

Awareness of breast cancer has been increasing due to early detection, but the advanced disease has limited treatment options. There has been growing evidence on the role of miRNAs involved in regulating the resistance in several cancers. We performed a comprehensive systematic review and meta-analysis on the role of miRNAs in influencing the chemoresistance and sensitivity of breast cancer. A bibliographic search was performed in PubMed and Science Direct based on the search strategy, and studies published until December 2018 were retrieved. The eligible studies were included based on the selection criteria, and a detailed systematic review and meta-analysis were performed based on PRISMA guidelines. A random-effects model was utilised to evaluate the combined effect size of the obtained hazard ratio and 95% confidence intervals from the eligible studies. Publication bias was assessed with Cochran's Q test, I2 statistic, Orwin and Classic fail-safe N test, Begg and Mazumdar rank correlation test, Duval and Tweedie trim and fill calculation and the Egger's bias indicator. A total of 4584 potential studies were screened. Of these, 85 articles were eligible for our systematic review and meta-analysis. In the 85 studies, 188 different miRNAs were studied, of which 96 were upregulated, 87 were downregulated and 5 were not involved in regulation. Overall, 24 drugs were used for treatment, with doxorubicin being prominently reported in 15 studies followed by Paclitaxel in 11 studies, and 5 drugs were used in combinations. We found only two significant HR values from the studies (miR-125b and miR-4443) and our meta-analysis results yielded a combined HR value of 0.748 with a 95% confidence interval of 0.508-1.100; p-value of 0.140. In conclusion, our results suggest there are different miRNAs involved in the regulation of chemoresistance through diverse drug genetic targets. These biomarkers play a crucial role in guiding the effective diagnostic and prognostic efficiency of breast cancer. The screening of miRNAs as a theragnostic biomarker must be brought into regular practice for all diseases. We anticipate that our study serves as a reference in framing future studies and clinical trials for utilising miRNAs and their respective drug targets.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , MicroRNAs/genética , Biomarcadores Farmacológicos , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , MicroRNAs/biossíntese , Prognóstico , Transcriptoma
6.
BMC Plant Biol ; 19(1): 405, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31521126

RESUMO

BACKGROUND: Cotton is one of the most important commercial crops as the source of natural fiber, oil and fodder. To protect it from harmful pest populations number of newer transgenic lines have been developed. For quick expression checks in successful agriculture qPCR (quantitative polymerase chain reaction) have become extremely popular. The selection of appropriate reference genes plays a critical role in the outcome of such experiments as the method quantifies expression of the target gene in comparison with the reference. Traditionally most commonly used reference genes are the "house-keeping genes", involved in basic cellular processes. However, expression levels of such genes often vary in response to experimental conditions, forcing the researchers to validate the reference genes for every experimental platform. This study presents a data science driven unbiased genome-wide search for the selection of reference genes by assessing variation of > 50,000 genes in a publicly available RNA-seq dataset of cotton species Gossypium hirsutum. RESULT: Five genes (TMN5, TBL6, UTR5B, AT1g65240 and CYP76B6) identified by data-science driven analysis, along with two commonly used reference genes found in literature (PP2A1 and UBQ14) were taken through qPCR in a set of 33 experimental samples consisting of different tissues (leaves, square, stem and root), different stages of leaf (young and mature) and square development (small, medium and large) in both transgenic and non-transgenic plants. Expression stability of the genes was evaluated using four algorithms - geNorm, BestKeeper, NormFinder and RefFinder. CONCLUSION: Based on the results we recommend the usage of TMN5 and TBL6 as the optimal candidate reference genes in qPCR experiments with normal and transgenic cotton plant tissues. AT1g65240 and PP2A1 can also be used if expression study includes squares. This study, for the first time successfully displays a data science driven genome-wide search method followed by experimental validation as a method of choice for selection of stable reference genes over the selection based on function alone.


Assuntos
Genoma de Planta/genética , Gossypium/genética , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Proteínas de Plantas/genética
8.
PLoS One ; 13(4): e0195796, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29677191

RESUMO

E487K point mutation of aldehyde dehydrogenase (ALDH) 2 (ALDH2*2) in East Asians intrinsically lowers ALDH2 activity. ALDH2*2 is associated with diabetic cardiomyopathy. Diabetic patients exhibit heart failure of preserved ejection fraction (HFpEF) i.e. while the systolic heart function is preserved in them, they may exhibit diastolic dysfunction, implying a jeopardized myocardial health. Currently, it is challenging to detect cardiac functional deterioration in diabetic mice. Stress echocardiography (echo) in the clinical set-up is a procedure used to measure cardiac reserve and impaired cardiac function in coronary artery diseases. Therefore, we hypothesized that high-fat diet fed type-2 diabetic ALDH2*2 mutant mice exhibit HFpEF which can be measured by cardiac echo stress test methodology. We induced type-2 diabetes in 12-week-old male C57BL/6 and ALDH2*2 mice through a high-fat diet. At the end of 4 months of DM induction, we measured the cardiac function in diabetic and control mice of C57BL/6 and ALDH2*2 genotypes by conscious echo. Subsequently, we imposed exercise stress by allowing the mice to run on the treadmill until exhaustion. Post-stress, we measured their cardiac function again. Only after treadmill running, but not at rest, we found a significant decrease in % fractional shortening and % ejection fraction in ALDH2*2 mice with diabetes compared to C57BL/6 diabetic mice as well as non-diabetic (control) ALDH2*2 mice. The diabetic ALDH2*2 mice also exhibited poor maximal running speed and distance. Our data suggest that high-fat fed diabetic ALDH2*2 mice exhibit HFpEF and treadmill exercise stress echo test is able to determine this HFpEF in the diabetic ALDH2*2 mice.


Assuntos
Aldeído-Desidrogenase Mitocondrial/genética , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 2/complicações , Dieta Hiperlipídica/efeitos adversos , Insuficiência Cardíaca/diagnóstico por imagem , Mutação Puntual , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/fisiopatologia , Ecocardiografia sob Estresse , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Volume Sistólico
9.
Mol Cell Biol ; 38(2)2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29061732

RESUMO

The migration of chromosomes during mitosis is mediated primarily by kinesins that bind to the chromosomes and move along the microtubules, exerting pulling and pushing forces on the centrosomes. We report that a DNA replication protein, Sld5, localizes to the centrosomes, resisting the microtubular pulling forces experienced during chromosome congression. In the absence of Sld5, centriolar satellites, which normally cluster around the centrosomes, are dissipated throughout the cytoplasm, resulting in the loss of their known function of recruiting the centrosomal protein, pericentrin. We observed that Sld5-deficient centrosomes lacking pericentrin were unable to endure the CENP-E- and Kid-mediated microtubular forces that converge on the centrosomes during chromosome congression, resulting in monocentriolar and acentriolar spindle poles. The minus-end-directed kinesin-14 motor protein, HSET, sustains the traction forces that mediate centrosomal fragmentation in Sld5-depleted cells. Thus, we report that a DNA replication protein has an as yet unknown function of ensuring spindle pole resistance to traction forces exerted during chromosome congression.


Assuntos
Centríolos/metabolismo , Centrossomo/fisiologia , Proteínas Cromossômicas não Histona/metabolismo , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Autoantígenos/genética , Autoantígenos/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Centríolos/genética , Centrossomo/química , Proteínas Cromossômicas não Histona/genética , Cromossomos Humanos/metabolismo , Dano ao DNA , Células HeLa , Humanos , Interfase/fisiologia , Microtúbulos/química , Microtúbulos/fisiologia , Mitose , Polos do Fuso/fisiologia , Polos do Fuso/ultraestrutura , Imagem com Lapso de Tempo
10.
Nucleic Acids Res ; 43(10): 4962-74, 2015 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-25916848

RESUMO

The primary eukaryotic single-stranded DNA-binding protein, Replication protein A (RPA), binds to single-stranded DNA at the sites of DNA damage and recruits the apical checkpoint kinase, ATR via its partner protein, ATRIP. It has been demonstrated that absence of RPA incapacitates the ATR-mediated checkpoint response. We report that in the absence of RPA, human single-stranded DNA-binding protein 1 (hSSB1) and its partner protein INTS3 form sub-nuclear foci, associate with the ATR-ATRIP complex and recruit it to the sites of genomic stress. The ATRIP foci formed after RPA depletion are abrogated in the absence of INTS3, establishing that hSSB-INTS3 complex recruits the ATR-ATRIP checkpoint complex to the sites of genomic stress. Depletion of homologs hSSB1/2 and INTS3 in RPA-deficient cells attenuates Chk1 phosphorylation, indicating that the cells are debilitated in responding to stress. We have identified that TopBP1 and the Rad9-Rad1-Hus1 complex are essential for the alternate mode of ATR activation. In summation, we report that the single-stranded DNA-binding protein complex, hSSB1/2-INTS3 can recruit the checkpoint complex to initiate ATR signaling.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas Mitocondriais/metabolismo , Proteína de Replicação A/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular , Quinase 1 do Ponto de Checagem , DNA de Cadeia Simples/metabolismo , Células HeLa , Humanos , Proteínas Quinases/metabolismo , Interferência de RNA , Proteína de Replicação A/genética , Transdução de Sinais , Estresse Fisiológico/genética
11.
Nucleic Acids Res ; 40(15): 7332-46, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22570418

RESUMO

When mammalian cells experience radiation insult, DNA replication is stalled to prevent erroneous DNA synthesis. UV-irradiation triggers proteolysis of Mcm10, an essential human replication factor, inhibiting the ongoing replication. Here, we report that Mcm10 associates with E3 ubiquitin ligase comprising DNA damage-binding protein, DDB1, cullin, Cul4 and ring finger protein, Roc1. Depletion of DDB1, Roc1 or Cul4 abrogates the UV-triggered Mcm10 proteolysis, implying that Cul4-Roc1-DDB1 ubiquitin ligase mediates Mcm10 downregulation. The purified Cul4-Roc1-DDB1 complex ubiquitinates Mcm10 in vitro, proving that Mcm10 is its substrate. By screening the known DDB1 interacting proteins, we discovered that VprBP is the substrate recognition subunit that targets Mcm10 for degradation. Hence, these results establish that Cul4-DDB1-VprBP ubiquitin ligase mediates the stress-induced proteolysis of replication factor, Mcm10.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas Culina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ciclo Celular/química , Linhagem Celular , Replicação do DNA , Regulação da Expressão Gênica , Células HeLa , Humanos , Proteínas de Manutenção de Minicromossomo , Proteínas Serina-Treonina Quinases , Estrutura Terciária de Proteína , Proteólise , Estresse Fisiológico/genética , Transcrição Gênica , Ubiquitina-Proteína Ligases , Ubiquitinação , Raios Ultravioleta
12.
BMC Cell Biol ; 11: 84, 2010 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-20979666

RESUMO

BACKGROUND: Mcm10 protein is essential for initiation and elongation phases of replication. Human cells proteolyze Mcm10 during mitosis, presumably to ensure a single round of replication. It has been proposed that anaphase promoting complex ubiquitinates Mcm10 in late M and early G1 phases. RESULTS: In contrast to the previous work, we report that the degradation of Mcm10 is initiated at the onset of mitosis. Immunoblotting and immunofluorescence assays display that Mcm10 levels are low in all phases of mitosis. We report that Mcm10 degradation is not dependent on anaphase promoting complex. Further, the proteolysis in M-phase can be independently mediated by non-overlapping regions of Mcm10, apparently employing a redundant mechanism to ensure downregulation. CONCLUSIONS: It is believed that the proteolysis of Mcm10 during mitosis is a vital mechanism to prevent aberrant initiation of replication and the present study describes the regulation of Mcm10 during this phase of the cell-cycle.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Divisão Celular , Linhagem Celular , Ciclina A/genética , Ciclina A/metabolismo , Fase G1 , Humanos , Proteínas de Manutenção de Minicromossomo , Mitose , Interferência de RNA , RNA Interferente Pequeno/metabolismo
13.
IUBMB Life ; 62(10): 764-75, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20945455

RESUMO

When mammalian cells experience DNA damaging stress, they block DNA replication to avoid erroneous replication of the damaged template. The cells that are unable to respond to DNA damage continue faulty DNA replication that results in incorporation of genomic lesions. To understand the regulation of replication machinery during stress, systemic studies have been carried out but they have been restricted to the evaluation of the mRNA levels and therefore have not been able to identify post-transcriptional changes, vital for immediate blocking of the progressing DNA replication. We have recently discovered that an essential replication factor is downregulated by radiation stress. In this study, we have carried out a systematic evaluation of protein levels of entire replication apparatus after different types of DNA damage. We report that, independent of the status of p53 and retinoblastoma protein, mammalian cells choose targets that are essential for prereplication, preinitiation, and elongation phases of replication. We imposed different kinds of stress to discern whether similar or unique responses are invoked, and we propose a model for inhibition of replication machinery in which mammalian cells target specific essential replication factors based on the experienced stress.


Assuntos
Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Replicação do DNA , Peróxido de Hidrogênio/farmacologia , Hidroxiureia/farmacologia , Linhagem Celular Tumoral , Dano ao DNA , Replicação do DNA/efeitos dos fármacos , Replicação do DNA/efeitos da radiação , Raios gama , Células HeLa , Humanos , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta
14.
J Biol Chem ; 285(11): 8352-62, 2010 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-20064936

RESUMO

We report that upon UV radiation insult, mammalian cells specifically down-regulate Mcm10, a protein essential for the initiation and elongation phases of DNA replication. The levels of a majority of replication factors remain unaffected under this condition, implying that Mcm10 is a key node in the regulation of the replication machinery. High doses of ionizing gamma radiation and exposure to a combination of DNA-damaging chemicals do not decrease Mcm10 protein levels, demonstrating that Mcm10 down-regulation is triggered only by UV-specific damage. The decrease of Mcm10 protein levels is not caused by transcriptional inhibition or cleavage by apoptotic enzymes, but results from degradation by the 26 S proteasome. UV-triggered degradation of Mcm10 requires its linker or C-terminal domain. In addition, Mcm10 down-regulation is not limited to cells from a particular lineage. Therefore, our study reveals a mechanism by which mammalian cells effectively inhibit the replication machinery during stress to prevent it from drifting toward a catastrophic path of genomic instability.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Replicação do DNA/fisiologia , Replicação do DNA/efeitos da radiação , Raios Ultravioleta , Antibióticos Antineoplásicos/toxicidade , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Divisão Celular/fisiologia , Divisão Celular/efeitos da radiação , Dano ao DNA/fisiologia , Reparo do DNA/fisiologia , Relação Dose-Resposta à Radiação , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/efeitos da radiação , Raios gama , Células HeLa , Humanos , Proteínas de Manutenção de Minicromossomo , Osteossarcoma , Complexo de Endopeptidases do Proteassoma/metabolismo , Estrutura Terciária de Proteína , RNA Interferente Pequeno , Fase S/fisiologia , Fase S/efeitos da radiação , Estresse Fisiológico/fisiologia , Estresse Fisiológico/efeitos da radiação , Transcrição Gênica/fisiologia
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