Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 18.606
Filtrar
1.
Biomaterials ; 313: 122777, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39222545

RESUMEN

Telomere length plays a crucial role in cellular aging and the risk of diseases. Unlike normal cells, cancer cells can extend their own survival by maintaining telomere stability through telomere maintenance mechanism. Therefore, regulating the lengths of telomeres have emerged as a promising approach for anti-cancer treatment. In this study, we introduce a nanoscale octopus-like structure designed to induce physical entangling of telomere, thereby efficiently triggering telomere dysfunction. The nanoscale octopus, composed of eight-armed PEG (8-arm-PEG), are functionalized with cell penetrating peptide (TAT) to facilitate nuclear entry and are covalently bound to N-Methyl Mesoporphyrin IX (NMM) to target G-quadruplexes (G4s) present in telomeres. The multi-armed configuration of the nanoscale octopus enables targeted binding to multiple G4s, physically disrupting and entangling numerous telomeres, thereby triggering telomere dysfunction. Both in vitro and in vivo experiments indicate that the nanoscale octopus significantly inhibits cancer cell proliferation, induces apoptosis through telomere entanglement, and ultimately suppresses tumor growth. This research offers a novel perspective for the development of innovative anti-cancer interventions and provides potential therapeutic options for targeting telomeres.


Asunto(s)
Apoptosis , Telómero , Telómero/metabolismo , Apoptosis/efectos de los fármacos , Humanos , Animales , Línea Celular Tumoral , Ratones , G-Cuádruplex/efectos de los fármacos , Ratones Desnudos , Polietilenglicoles/química , Proliferación Celular/efectos de los fármacos , Ratones Endogámicos BALB C , Neoplasias/patología , Neoplasias/tratamiento farmacológico , Femenino , Péptidos de Penetración Celular/química , Péptidos de Penetración Celular/farmacología , Nanoestructuras/química
2.
J Chem Phys ; 161(10)2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39248241

RESUMEN

Telomeric G-quadruplexes (G4s) are non-canonical DNA structures composed of TTAGGG repeats. They are extensively studied both as biomolecules key for genome stability and as promising building blocks and functional elements in synthetic biology and nanotechnology. This is why it is extremely important to understand how the interaction between G4s is affected by their topology. We used small-angle x-ray scattering to investigate the end-to-end stacking of antiparallel telomeric G-quadruplexes formed by the sequence AG3(T2AG3)3. To represent the experimental data, we developed a highly efficient coarse-grained fitting tool, which successfully described the samples as an equilibrium mixture of monomeric and dimeric G4 species. Our findings indicate that the antiparallel topology prevents the formation of long multimeric structures under self-crowding conditions, unlike the hybrid/parallel structures formed by the same DNA sequence. This result supports the idea that the stacking of monomeric G-quadruplexes is strongly affected by the presence of diagonal loops.


Asunto(s)
G-Cuádruplex , Dispersión del Ángulo Pequeño , Telómero , Telómero/química , ADN/química , Difracción de Rayos X
3.
Int J Med Sci ; 21(11): 2065-2080, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39239547

RESUMEN

Sarcoma is a rare tumor derived from the mesenchymal tissue and mainly found in children and adolescents. The outcome for patients with sarcoma is relatively poor compared with that for many other solid malignant tumors. Sarcomas have a highly heterogeneous pathogenesis, histopathology and biological behavior. Dysregulated signaling pathways and various gene mutations are frequently observed in sarcomas. The telomere maintenance mechanism (TMM) has recently been considered as a prognostic factor for patients with sarcomas, and alternative lengthening of telomeres (ALT) positivity has been correlated with poor outcomes in patients with several types of sarcomas. Therefore, telomeres and telomerases may be useful targets for treating sarcomas. This review aims to provide an overview of telomere and telomerase biology in sarcomas.


Asunto(s)
Sarcoma , Telomerasa , Homeostasis del Telómero , Telómero , Humanos , Telomerasa/genética , Telomerasa/metabolismo , Sarcoma/genética , Sarcoma/terapia , Sarcoma/patología , Telómero/genética , Telómero/metabolismo , Homeostasis del Telómero/genética , Pronóstico , Mutación
4.
J Vis Exp ; (210)2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39283143

RESUMEN

Telomeres, the protective structures at the ends of chromosomes, are crucial for maintaining cellular longevity and genome stability. Their proper function depends on tightly regulated processes of replication, elongation, and damage response. The shelterin complex, especially Telomere Repeat-binding Factor 1 (TRF1) and TRF2, plays a pivotal role in telomere protection and has emerged as a potential anti-cancer target for drug discovery. These proteins bind to the repetitive telomeric DNA motif TTAGGG, facilitating the formation of protective structures and recruitment of other telomeric proteins. Structural methods and advanced imaging techniques have provided insights into telomeric protein-DNA interactions, but probing the dynamic processes requires single-molecule approaches. Tools like magnetic tweezers, optical tweezers, and atomic force microscopy (AFM) have been employed to study telomeric protein-DNA interactions, revealing important details such as TRF2-dependent DNA distortion and telomerase catalysis. However, the preparation of single-molecule constructs with telomeric repetitive motifs continues to be a challenging task, potentially limiting the breadth of studies utilizing single-molecule mechanical methods. To address this, we developed a method to study interactions using full-length human telomeric DNA with magnetic tweezers. This protocol describes how to express and purify TRF2, prepare telomeric DNA, set up single-molecule mechanical assays, and analyze data. This detailed guide will benefit researchers in telomere biology and telomere-targeted drug discovery.


Asunto(s)
ADN , Telómero , ADN/química , ADN/metabolismo , ADN/genética , Telómero/metabolismo , Telómero/química , Humanos , Proteína 2 de Unión a Repeticiones Teloméricas/metabolismo , Proteína 2 de Unión a Repeticiones Teloméricas/química , Proteína 2 de Unión a Repeticiones Teloméricas/genética , Proteínas de Unión a Telómeros/metabolismo , Proteínas de Unión a Telómeros/química , Proteínas de Unión a Telómeros/genética , Imagen Individual de Molécula/métodos , Proteína 1 de Unión a Repeticiones Teloméricas/metabolismo , Proteína 1 de Unión a Repeticiones Teloméricas/química , Proteína 1 de Unión a Repeticiones Teloméricas/genética , Pinzas Ópticas
5.
Gigascience ; 132024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-39283687

RESUMEN

BACKGROUND: The Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis, YFP) and the East Asian finless porpoise (Neophocaena asiaeorientalis sunameri, EFP) are 2 subspecies of the narrow-ridged finless porpoise that live in freshwater and saltwater, respectively. The main objective of this study was to provide contiguous chromosome-level genome assemblies for YFP and EFP. RESULTS: Here, we generated and upgraded the genomes of YFP and EFP at the telomere-to-telomere level through the integration of PacBio HiFi long reads, ultra-long ONT reads, and Hi-C sequencing data with a total size of 2.48 Gb and 2.50 Gb, respectively. The scaffold N50 of 2 genomes was 125.12 Mb (YFP) and 128 Mb (EFP) with 1 contig for 1 chromosome. The telomere repeat and centromere position were clearly identified in both YFP and EFP genomes. In total, 5,480 newfound genes were detected in the YFP genome, including 56 genes located in the newly identified centromere regions. Additionally, synteny blocks, structural similarities, phylogenetic relationships, gene family expansion, and inference of selection were studied in connection with the genomes of other related mammals. CONCLUSIONS: Our research findings provide evidence for the gradual adaptation of EFP in a marine environment and the potential sensitivity of YFP to genetic damage. Compared to the 34 cetacean genomes sourced from public databases, the 2 new assemblies demonstrate superior continuity with the longest contig N50 and scaffold N50 values, as well as the lowest number of contigs. The improvement of telomere-to-telomere gap-free reference genome resources supports conservation genetics and population management for finless porpoises.


Asunto(s)
Genoma , Marsopas , Telómero , Marsopas/genética , Telómero/genética , Animales , Especies en Peligro de Extinción , Filogenia , Genómica/métodos , Pueblos del Este de Asia
6.
Nat Commun ; 15(1): 8102, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39284827

RESUMEN

Mammalian DNA replication relies on various DNA helicase and nuclease activities to ensure accurate genetic duplication, but how different helicase and nuclease activities are properly directed remains unclear. Here, we identify the ubiquitin-specific protease, USP50, as a chromatin-associated protein required to promote ongoing replication, fork restart, telomere maintenance, cellular survival following hydroxyurea or pyridostatin treatment, and suppression of DNA breaks near GC-rich sequences. We find that USP50 supports proper WRN-FEN1 localisation at or near stalled replication forks. Nascent DNA in cells lacking USP50 shows increased association of the DNA2 nuclease and RECQL4 and RECQL5 helicases and replication defects in cells lacking USP50, or FEN1 are driven by these proteins. Consequently, suppression of DNA2 or RECQL4/5 improves USP50-depleted cell resistance to agents inducing replicative stress and restores telomere stability. These data define an unexpected regulatory protein that promotes the balance of helicase and nuclease use at ongoing and stalled replication forks.


Asunto(s)
ADN Helicasas , Replicación del ADN , RecQ Helicasas , Helicasa del Síndrome de Werner , RecQ Helicasas/metabolismo , RecQ Helicasas/genética , Replicación del ADN/efectos de los fármacos , Humanos , Helicasa del Síndrome de Werner/metabolismo , Helicasa del Síndrome de Werner/genética , ADN Helicasas/metabolismo , ADN Helicasas/genética , Telómero/metabolismo , Telómero/genética , Endonucleasas de ADN Solapado/metabolismo , Endonucleasas de ADN Solapado/genética , Proteasas Ubiquitina-Específicas/metabolismo , Proteasas Ubiquitina-Específicas/genética , Células HeLa , Células HEK293 , Homeostasis del Telómero/efectos de los fármacos , Cromatina/metabolismo
7.
Sci Rep ; 14(1): 21594, 2024 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-39284832

RESUMEN

Shortening of telomere length (TL) is correlated with many age-related disorders and is a hallmark of biological aging. This study used proteome-wide Mendelian randomization to identify the protein biomarkers associated with telomere length. Protein quantitative trait loci (pQTL) were derived from two studies, the deCODE Health study (4907 plasma proteins) and the UK Biobank Pharma Proteomics Project (2923 plasma proteins). Summary data from genome-wide association studies (GWAS) for TL were obtained from the UK Biobank (472,174 cases) and GWAS Catalog (418,401 cases). The association between proteins and TL was further assessed using colocalization and summary data-based Mendelian randomization (SMR) analyses. The protein-protein network, druggability assessment, and phenome-wide MR were used to further evaluate the potential biological effects, druggability, and safety of the target proteins. Proteome-wide MR analysis identified 22 plasma proteins that were causally associated with telomere length. Five of these proteins (APOE, SPRED2, MAX, RALY, and PSMB1) had the highest evidence of association with TL and should be prioritized. This study revealed telomere length-related protein biomarkers, providing new insights into the development of new treatment targets for chronic diseases and anti-aging intervention strategies.


Asunto(s)
Biomarcadores , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Proteómica , Sitios de Carácter Cuantitativo , Humanos , Biomarcadores/sangre , Proteómica/métodos , Homeostasis del Telómero , Telómero/metabolismo , Telómero/genética , Proteoma/metabolismo , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Acortamiento del Telómero
8.
Sci Adv ; 10(37): eadq2311, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39259784

RESUMEN

Telomere length (TL) is increasingly recognized as a molecular marker that reflects how reproductive aging affects intergenerational transmissions. Here, we investigated the effects of parental age on offspring survival and the regulation of TL by examining the telomere-elongating activity of telomerase in the Pacific oyster. We assessed the classical hallmarks of aging in parents at three age classes (young, middle-aged, and old) and crossbred them using a split-brood design to examine the consequences of the nine maternal-by-paternal age combinations on their offspring. Reproductive aging leads to increased larval mortality and accelerated telomere shortening in spats, rendering them more susceptible to infection by the Ostreid herpesvirus. Viral exposure stimulates telomerase activity, a response that we identified as adaptive, but weakened by parental aging. While telomerase lengthens a spat's telomere, paradoxically, longer individual TL predicts higher mortality in adults. The telomerase-telomere complex appeared as a conservative biomarker for distinguishing survivors and losers upon exposure to polymicrobial diseases.


Asunto(s)
Envejecimiento , Reproducción , Telomerasa , Animales , Telomerasa/metabolismo , Telomerasa/genética , Telómero/metabolismo , Telómero/genética , Herpesviridae/fisiología , Femenino , Homeostasis del Telómero , Ostreidae/virología
9.
World J Surg Oncol ; 22(1): 245, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261898

RESUMEN

BACKGROUND: Telomeres are a critical component of chromosome integrity and are essential to the development of cancer and cellular senescence. The regulation of breast cancer by telomere-associated lncRNAs is not fully known, though. The goals of this study were to describe predictive telomere-related LncRNAs (TRL) in breast cancer and look into any possible biological roles for these RNAs. METHODS: We obtained RNA-seq data, pertinent clinical data, and a list of telomere-associated genes from the cancer genome atlas and telomere gene database, respectively. We subjected differentially expressed TRLs to co-expression analysis and univariate Cox analysis to identify a prognostic TRL. Using LASSO regression analysis, we built a prognostic model with 14 TRLs. The accuracy of the model's prognostic predictions was evaluated through the utilization of Kaplan-Meier (K-M) analysis as well as receiver operating characteristic (ROC) curve analysis. Additionally, immunological infiltration and immune drug prediction were done using this model. Patients with breast cancer were divided into two subgroups using cluster analysis, with the latter analyzed further for variations in response to immunotherapy, immune infiltration, and overall survival, and finally, the expression of 14-LncRNAs was validated by RT-PCR. RESULTS: We developed a risk model for the 14-TRL, and we used ROC curves to demonstrate how accurate the model is. The model may be a standalone prognostic predictor for patients with breast cancer, according to COX regression analysis. The immune infiltration and immunotherapy results indicated that the high-risk group had a low level of PD-1 sensitivity and a high number of macrophages infiltrating. In addition, we've discovered a number of small-molecule medicines with considerable for use in treating high-risk groups. The cluster 2 subtype showed the highest immune infiltration, the highest immune checkpoint expression, and the worst prognosis among the two subtypes defined by cluster analysis, which requires more attention and treatment. CONCLUSION: As a possible biomarker, the proposed 14-TRL signature could be utilized to evaluate clinical outcomes and treatment efficacy in breast cancer patients.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama , ARN Largo no Codificante , Telómero , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/mortalidad , Femenino , ARN Largo no Codificante/genética , Pronóstico , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Telómero/genética , Tasa de Supervivencia , Regulación Neoplásica de la Expresión Génica , Persona de Mediana Edad , Curva ROC , Estudios de Seguimiento , Perfilación de la Expresión Génica , Estimación de Kaplan-Meier
10.
Genome Biol ; 25(1): 244, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39285474

RESUMEN

BACKGROUND: Telomeric repeat arrays at the ends of chromosomes are highly dynamic in composition, but their repetitive nature and technological limitations have made it difficult to assess their true variation in genome diversity surveys. RESULTS: We have comprehensively characterized the sequence variation immediately adjacent to the canonical telomeric repeat arrays at the very ends of chromosomes in 74 genetically diverse Arabidopsis thaliana accessions. We first describe several types of distinct telomeric repeat units and then identify evolutionary processes such as local homogenization and higher-order repeat formation that shape diversity of chromosome ends. By comparing largely isogenic samples, we also determine repeat number variation of the degenerate and variant telomeric repeat array at both the germline and somatic levels. Finally, our analysis of haplotype structure uncovers chromosome end-specific patterns in the distribution of variant telomeric repeats, and their linkage to the more proximal non-coding region. CONCLUSIONS: Our findings illustrate the spectrum of telomeric repeat variation at multiple levels in A. thaliana-in germline and soma, across all chromosome ends, and across genetic groups-thereby expanding our knowledge of the evolution of chromosome ends.


Asunto(s)
Arabidopsis , Cromosomas de las Plantas , Variación Genética , Telómero , Arabidopsis/genética , Telómero/genética , Secuencias Repetitivas de Ácidos Nucleicos , Haplotipos , Evolución Molecular , Genoma de Planta
11.
Front Immunol ; 15: 1438838, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39234237

RESUMEN

Background: The purpose of this study is to investigate the causal effect and potential mechanisms between telomere length and abdominal aortic aneurysm (AAA). Methods: Summary statistics of telomere length and AAA were derived from IEU open genome-wide association studies and FinnGen R9, respectively. Bi-directional Mendelian randomization (MR) analysis was conducted to reveal the causal relationship between AAA and telomere length. Three transcriptome datasets were retrieved from the Gene Expression Omnibus database and telomere related genes was down-loaded from TelNet. The overlapping genes of AAA related differentially expressed genes (DEGs), module genes, and telomere related genes were used for further investigation. Telomere related diagnostic biomarkers of AAA were selected with machine learning algorisms and validated in datasets and murine AAA model. The correlation between biomarkers and immune infiltration landscape was established. Results: Telomere length was found to have a suggestive negative associations with AAA [IVW, OR 95%CI = 0.558 (0.317-0.701), P < 0.0001], while AAA showed no suggestive effect on telomere length [IVW, OR 95%CI = 0.997 (0.990-1.004), P = 0.4061]. A total of 40 genes was considered as telomere related DEGs of AAA. PLCH2, PRKCQ, and SMG1 were selected as biomarkers after multiple algorithms and validation. Immune infiltration analysis and single cell mRNA analysis revealed that PLCH2 and PRKCQ were mainly expressed on T cells, while SMG1 predominantly expressed on T cells, B cells, and monocytes. Murine AAA model experiments further validated the elevated expression of biomarkers. Conclusion: We found a suggestive effect of telomere length on AAA and revealed the potential biomarkers and immune mechanism of telomere length on AAA. This may shed new light for diagnosis and therapeutics on AAA.


Asunto(s)
Aneurisma de la Aorta Abdominal , Estudio de Asociación del Genoma Completo , Homeostasis del Telómero , Telómero , Aneurisma de la Aorta Abdominal/genética , Aneurisma de la Aorta Abdominal/inmunología , Animales , Ratones , Humanos , Telómero/genética , Análisis de la Aleatorización Mendeliana , Biomarcadores , Masculino , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Transcriptoma , Predisposición Genética a la Enfermedad
12.
PLoS One ; 19(9): e0308924, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39231146

RESUMEN

Living with chronic pain is associated with substantial suffering and high societal costs. Patient reported outcomes (PROM's) and cellular ageing should be considered in pain management. The aim of this study was to explore correlations of PROM's and cellular ageing (telomere length [TL] and telomerase activity [TA]) amongst patients with chronic non-malignant pain. This was an explorative pilot study with cross-sectional design and recruitment was done at two pain rehabilitation facilities in Sweden, with inpatient setting/integrative care and outpatient setting/multimodal care, respectively. Eighty-four patients were enrolled by referral to pain rehabilitation in Sweden. The main outcome measures collected after admission in addition to TL and TA were the following PROMs: Numerical Rating Scale (NRS), Chronic Pain Acceptance Questionnaire (CPAQ), Hospital Anxiety and Depression Scale (HADS), Five Facets Mindfulness Questionnaire (FFMQ), WHO Quality of Life-Spiritual, Religious and Personal Beliefs (WHOQoL-SRPB) and EuroQol 5 Dimensions (EQ-5D). All the PROM's showed evidence of poor overall health status among the participants. TL correlated negatively with HADS score (r = -.219, p = .047) and positively with WHOQoL-SRPB (r = .224, p = .052). TL did not correlate with any of the pain measures. TA correlated positively with pain spread (r = .222, p = .049). A mediation of the direct effect of spiritual well-being on TL by anxiety and depression could be shown (b = 0.008; p = .045). The correlations between TL and SRPB and anxiety and depression suggest some importance of emotional and SRPB dimensions in pain management, with implications for cellular aging, which may warrant further study. Trial registration: ClinicalTrials.gov Identifier: NCT02459639.


Asunto(s)
Dolor Crónico , Espiritualidad , Telómero , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor Crónico/psicología , Estudios Transversales , Depresión/psicología , Emociones , Medición de Resultados Informados por el Paciente , Proyectos Piloto , Calidad de Vida , Religión , Encuestas y Cuestionarios , Suecia , Telomerasa/metabolismo , Telomerasa/genética , Telómero/genética
13.
Nutrients ; 16(17)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39275278

RESUMEN

Telomeres are ribonucleoprotein structures that form a protective buffer at the ends of chromosomes, maintaining genomic integrity during the cell cycle. A decrease in average telomere length is associated with with age and with aging-related diseases such as cancer and cardiovascular disease. In this study, we conducted a randomized, double-blind, placebo-controlled trial over six months to compare the effects of the Astragalus-based supplement versus a placebo on telomere length (TL) in 40 healthy volunteers (mean age 56.1 ± 6.0 years). Twenty subjects received the supplement, and 20 received placebo capsules. All participants completed the study, and no adverse side effects were reported at six months. Subjects taking the Astragalus-based supplement exhibited significantly longer median TL (p = 0.01) and short TL (p = 0.004), along with a lower percentage of short telomeres, over the six-month period, while the placebo group showed no change in TL. This trial confirmed that the supplement significantly lengthens both median and short telomeres by increasing telomerase activity and reducing the percentage of short telomeres (<3 Kbp) in a statistically and possibly clinically significant manner. These results align with a previous open prospective trial, which found no toxicity associated with the supplement's intake. These findings suggest that this Astragalus-based supplement warrants further investigation for its potential benefits in promoting health, extending life expectancy, and supporting healthy aging.


Asunto(s)
Planta del Astrágalo , Suplementos Dietéticos , Telomerasa , Telómero , Humanos , Método Doble Ciego , Persona de Mediana Edad , Masculino , Femenino , Planta del Astrágalo/química , Telómero/efectos de los fármacos , Telomerasa/metabolismo , Homeostasis del Telómero/efectos de los fármacos , Acortamiento del Telómero/efectos de los fármacos
14.
Int J Mol Sci ; 25(17)2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39273401

RESUMEN

Aging is an exceptionally complex process that depends on genetic, environmental, and lifestyle factors. Previous studies within the International HLA and Immunogenetics Workshop (IHIWS) component "Immunogenetics of Ageing" showed that longevity is associated with positive selection of HLA-DRB1*11- and DRB1*16-associated haplotypes, shown to be protective against diseases. Within the 18th IHIWS, we aimed to investigate the relevance of telomere length for successful aging and its association with classical HLAs. In total 957 individuals from Bulgaria, Turkey, Romania, and Poland in two age groups, elderly individuals (age 65-99 years) and ethnically matched young group (age 18-64 years), were investigated. The obtained results confirmed interpopulation differences in the distribution of HLA alleles, documented the lengths of telomeres in analyzed populations, and demonstrated significant associations of telomere length with aging as well as with the presence of some HLA class I or class II alleles. They suggest that telomere length assessment combined with HLA genotyping may help identify immunogenetic profiles associated with longevity. The associations between HLA and telomeres support the theory that HLA genes influence the aging process. However, further research is needed to clarify the biological basis of the observed relationships.


Asunto(s)
Antígenos HLA , Longevidad , Humanos , Longevidad/genética , Anciano , Persona de Mediana Edad , Masculino , Adulto , Femenino , Anciano de 80 o más Años , Adolescente , Antígenos HLA/genética , Adulto Joven , Telómero/genética , Alelos , Homeostasis del Telómero , Envejecimiento/genética , Envejecimiento/inmunología , Haplotipos
15.
Horm Behav ; 165: 105631, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39232410

RESUMEN

Telomere length (TL) is an important cellular marker of biological aging impacting the brain and heart. However, how it is related to the brain (e.g., cognitive function and neuroanatomic architecture), and how these relationships may vary by sex and reproductive status, is not well established. Here we assessed the association between leukocyte TL and memory circuitry regional brain volumes and memory performance in early midlife, in relation to sex and reproductive status. Participants (N = 198; 95 females, 103 males; ages 45-55) underwent structural MRI and neuropsychological assessments of verbal, associative, and working memory. Overall, shorter TL was associated with smaller white matter volume in the parahippocampal gyrus and dorsolateral prefrontal cortex. In males, shorter TL was associated with worse working memory performance and corresponding smaller white matter volumes in the parahippocampal gyrus, anterior cingulate cortex, and dorsolateral prefrontal cortex. In females, the impact of cellular aging was revealed over the menopausal transition. In postmenopausal females, shorter TL was associated with poor associative memory performance and smaller grey matter volume in the right hippocampus. In contrast, TL was not related to memory performance or grey and white matter volumes in any memory circuitry region in pre/perimenopausal females. Results demonstrated that shorter TL is associated with worse memory function and smaller volume in memory circuitry regions in early midlife, an association that differs by sex and reproductive status. Taken together, TL may serve as an early indicator of sex-dependent brain abnormalities in early midlife.


Asunto(s)
Envejecimiento , Cognición , Leucocitos , Memoria , Menopausia , Humanos , Femenino , Persona de Mediana Edad , Masculino , Envejecimiento/fisiología , Leucocitos/fisiología , Cognición/fisiología , Menopausia/fisiología , Memoria/fisiología , Caracteres Sexuales , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Telómero/fisiología , Sustancia Gris/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiología , Pruebas Neuropsicológicas
16.
Integr Cancer Ther ; 23: 15347354241267979, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39256983

RESUMEN

Multiple myeloma is a hematological cancer caused by the uncontrolled proliferation of abnormal plasma cells in the bone marrow, leading to excessive immunoglobulin production. Our study aimed to examine the anticancer properties of BRF1A, a cannabinoid (CBD)-enriched product, on 2 myeloma cell lines: U266 and ARH-7. We treated U266 and ARH-77 myeloma cells with varying doses of BRF1A and measured the production of IgE and IgG antibodies using ELISA. Cell viability was assessed using trypan blue and CCK-8 assays. We measured the expression of genes related to the production of IgE and IgG antibodies, IgEH, and IgGH. We determined its effect on the expression of telomerase and its phosphorylated form as an indicator of telomere stabilization. Furthermore, we determined its effect on other cancer-related targets such as NF-ĸB, c-Myc, and TP53 in U266 cells using reverse transcription polymerase chain reaction (RT-PCR) and western blotting. BRF1A reduced myeloma cell IgE and IgG production in a time and dose-dependent manner. It also suppressed the expression of p-IκBα, p-NFκB (p65), and total NFκB protein, as well as XBP1u and XBP1s. It increased the gene and protein expression of telomere and hTERT and significantly increased cancer suppressor TP53 gene and p53 protein expression. Additionally, BRF1A decreased the c-Myc gene and protein expression. Our study has shown that a CBD-enriched product can reduce the growth of myeloma cells by suppressing the critical functions of IgE- and IgG-producing cells. This study could help bridge the gap in understanding how cannabinoid-containing products affect cancer, aging, telomere, and cancer-suppressor gene activity.


Asunto(s)
Cannabinoides , Mieloma Múltiple , Telomerasa , Telómero , Proteína p53 Supresora de Tumor , Humanos , Mieloma Múltiple/tratamiento farmacológico , Línea Celular Tumoral , Telómero/efectos de los fármacos , Telómero/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Cannabinoides/farmacología , Telomerasa/metabolismo , Supervivencia Celular/efectos de los fármacos , FN-kappa B/metabolismo , Inmunoglobulina E , Inmunoglobulina G , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos
17.
Comput Biol Med ; 181: 109064, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39216403

RESUMEN

BACKGROUND: Clinical therapeutic targets for leukemia remain to be identified and the causality between leukemia and telomere length is unclear. METHODS: This work employed cis expression quantitative trait locus (eQTL) for 2,200 druggable genes from the eQTLGen Consortium and genome-wide association studies (GWAS) summary data for telomere length in seven blood cell types from the UK Biobank, Netherlands Cohort as exposures. GWAS data for lymphoid leukemia (LL) and myeloid leukemia (ML) from FinnGen and Lee Lab were used as outcomes for discovery and replication cohorts, respectively. Robust Mendelian randomization (MR) findings were generated from seven MR models and a series of sensitivity analyses. Summary-data-based MR (SMR) analysis and transcriptome-wide association studies (TWAS) were further implemented to verify the association between identified druggable genes and leukemia. Single-cell type expression analysis was employed to identify the specific expression of leukemia casual genes on human bone marrow and peripheral blood immune cells. Multivariable MR analysis, linkage disequilibrium score regression (LDSC), and Bayesian colocalization analysis were performed to further validate the relationship between telomere length and leukemia. Mediation analysis was used to assess the effects of identified druggable genes affecting leukemia via telomere length. Phenome-wide MR (Phe-MR) analysis for assessing the effect of leukemia causal genes and telomere length on 1,403 disease phenotypes. RESULTS: Combining the results of the meta-analysis for MR estimates from two cohorts, SMR and TWAS analysis, we identified five LL causal genes (TYMP, DSTYK, PPIF, GDF15, FAM20A) and three ML causal genes (LY75, ADA, ABCA2) as promising drug targets for leukemia. Univariable MR analysis showed genetically predicted higher leukocyte telomere length increased the risk of LL (odds ratio [OR] = 2.33, 95 % confidence interval [95 % CI] 1.70-3.18; P = 1.33E-07), and there was no heterogeneity and horizontal pleiotropy. Evidence from the meta-analysis of two cohorts strengthened this finding (OR = 1.88, 95 % CI 1.06-3.05; P = 0.01). Multivariable MR analysis showed the causality between leukocyte telomere length and LL without interference from the other six blood cell telomere length (OR = 2.72, 95 % CI 1.88-3.93; P = 1.23E-07). Evidence from LDSC supported the positive genetic correlation between leukocyte telomere length and LL (rg = 0.309, P = 0.0001). Colocalization analysis revealed that the causality from leukocyte telomere length on LL was driven by the genetic variant rs770526 in the TERT region. The mediation analysis via two-step MR showed that the causal effect from TYMP on LL was partly mediated by leukocyte telomere length, with a mediated proportion of 12 %. CONCLUSION: Our study identified several druggable genes associated with leukemia risk and provided new insights into the etiology and drug development of leukemia. We also found that genetically predicted higher leukocyte telomere length increased LL risk and its potential mechanism of action.


Asunto(s)
Estudio de Asociación del Genoma Completo , Leucemia , Sitios de Carácter Cuantitativo , Humanos , Leucemia/genética , Análisis de la Aleatorización Mendeliana , Telómero/genética , Estudios de Cohortes , Homeostasis del Telómero/genética
18.
Int J Biol Macromol ; 277(Pt 3): 134126, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39097044

RESUMEN

DNA chains with sequential guanine (G) repeats can lead to the formation of G-quadruplexes (G4), which are found in functional DNA and RNA regions like telomeres and oncogene promoters. The development of molecules with adequate structural features to selectively stabilize G4 structures can counteract cell immortality, highly described for cancer cells, and also downregulate transcription events underlying cell apoptosis and/or senescence processes. We describe here, the efficiency of four highly charged porphyrins-phosphonium conjugates to act as G4 stabilizing agents. The spectrophotometric results allowed to select the conjugates P2-PPh3 and P3-PPh3 as the most promising ones to stabilize selectively G4 structures. Molecular dynamics simulation experiments were performed and support the preferential binding of P2-PPh3 namely to MYC and of P3-PPh3 to KRAS. The ability of both ligands to block the activity of Taq polymerase was confirmed and also their higher cytotoxicity against the two melanoma cell lines A375 and SK-MEL-28 than to immortalized skin keratinocytes. Both ligands present efficient cellular uptake, nuclear co-localization and high ability to generate 1O2 namely when interacting with G4 structure. The obtained data points the synthesized porphyrins as promising ligands to be used in a dual approach that can combine G4 stabilization and Photodynamic therapy (PDT).


Asunto(s)
G-Cuádruplex , Porfirinas , Telómero , G-Cuádruplex/efectos de los fármacos , Porfirinas/química , Porfirinas/farmacología , Humanos , Telómero/química , Línea Celular Tumoral , Compuestos Organofosforados/química , Compuestos Organofosforados/farmacología , Simulación de Dinámica Molecular , Ligandos , Oncogenes
19.
Int J Biol Macromol ; 277(Pt 3): 134300, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39097069

RESUMEN

Extensive bodies of research are dedicated to the study of seed aging with a particular focus on the roles of reactive oxygen species (ROS), and the ensuing oxidative damage during storage, as a primary cause of seed vigor decreasing. ROS diffuse to the nucleus and damage the telomeres, resulting in a loss of genetic integrity. Protection of telomeres 1 (POT1) is a telomeric protein that binds to the telomere region, and plays an essential role in maintaining genomic stability in plants. In this study, there were totally four MsPOT1 genes obtained from alfalfa genome. Expression analysis of four MsPOT1 genes in germinated seed presented the different expressions. Four MsPOT1 genes displayed high expression levels at the early stage of seed germination, Among the four POT1 genes, it was found that MS. gene040108 was significantly up-regulated in the early germination stage of CK seeds, but down-regulated in aged seeds. RT-qPCR assays and RNA-seq data revealed that MsPOT1-X gene was significantly induced by seed aging treatment. Transgenic seeds overexpressing MsPOT1-X gene in Arabidopsis thaliana and Medicago trunctula exhibited enhanced seed vigor, telomere length, telomerase activity associated with reduced H2O2 content. These results would provide a new way to understand aging stress-responsive MsPOT1 genes for genetic improvement of seed vigor. Although a key gene regulating seed vigor was identified in this study, the specific mechanism of MsPOT1-X gene regulating seed vigor needs to be further explored.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Medicago sativa , Proteínas de Plantas , Semillas , Medicago sativa/genética , Medicago sativa/metabolismo , Semillas/genética , Semillas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Telómero/metabolismo , Telómero/genética , Germinación/genética , Plantas Modificadas Genéticamente , Proteínas de Unión a Telómeros/metabolismo , Proteínas de Unión a Telómeros/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Especies Reactivas de Oxígeno/metabolismo
20.
Int J Mol Sci ; 25(16)2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39201686

RESUMEN

Telomeres play a crucial role in maintaining chromosomal integrity and regulating the number of cell divisions and have been associated with cellular aging. Telomere length (TL) has been widely studied in manifold cancer types; however, the results have been inconsistent. This systematic review and meta-analysis aims to analyze the evidence on the association between TL and head and neck cancer (HNC) risk. We comprehensively searched the literature in PubMed, Cochrane Library, and Scopus and identified nine eligible studies, which yielded 11 datasets. The odds ratios (ORs) and 95% confidence intervals (CIs) were used to ascertain the strength of the association. On the basis of the median TL, we defined two groups, short TL and long TL, with the latter being the reference group. Our analysis found a significant relationship between short TL and increased HNC risk (OR 1.38, 95% CI: 1.10-1.73, p = 0.005), while significant heterogeneity among the studies was noted. The subgroup analysis on HNC subtypes revealed a significant association between short TL and oral cancers (OR 2.08, 95% CI: 1.23-3.53, p = 0.007). Additionally, subgroup analysis indicates that adjustments for age, sex, and smoking did not affect the significance of our findings. In conclusion, our meta-analysis found evidence for an association between short TL and HNC risk, which could indicate that TL might act as a potential biomarker for HNC risk, but high-quality prospective studies are imperative to validate our findings.


Asunto(s)
Neoplasias de Cabeza y Cuello , Homeostasis del Telómero , Telómero , Humanos , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/patología , Telómero/genética , Telómero/metabolismo , Factores de Riesgo , Oportunidad Relativa
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA