Downregulation of MLF1 safeguards cardiomyocytes against senescence-associated chromatin opening
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE273659 | GEO | 2025/01/29
REPOSITORIES: GEO
Similar Datasets
Project description:Previous studies found that MLF1 mRNA levels tended to decline in aging hearts. Functional studies found that knockdown of MLF1 ameliorated the drug-induced cellular senescence phenotype. Here, we apply transcriptomics to explore the underlying molecular mechanisms.
2025-01-29 | GSE206754 | GEO
Project description:Previous studies found that MLF1 mRNA levels tended to decline in aging hearts. Functional studies found that knockdown of MLF1 ameliorated the drug-induced cellular senescence phenotype. Here, we apply transcriptomics to explore the underlying molecular mechanisms.
2025-01-29 | GSE207907 | GEO
Project description:Aging-associated cardiac hypertrophy (AACH) increases susceptibility to heart failure in the elderly. Chromatin remodeling contributes to the gene reprogramming in AACH; however, the intrinsic regulations remain elusive. We performed a transcriptome analysis for AACH in comparison with pressure-overload-induced pathological cardiac hypertrophy in mice and identified myeloid leukemia factor 1 (MLF1) as an aging-sensitive factor whose expression was reduced during aging but could be reversed by anti-aging administrations. In human AC16 cardiomyocytes, silencing MLF1 suppressed H2O2-induced cell senescence while the phenotype was exacerbated by MLF1 overexpression. RNA-seq analysis revealed that MLF1 functioned as a transcription activator, regulating genomic-clustered genes that mainly involved in inflammation and development. ATAC-seq analysis showed a prominent reduction in chromatin accessibility at the promoter regions of senescence effectors, like IL1B and p21, after MLF1 knockdown. Despite a potential interaction of MLF1 with the histone methyltransferase PRC2, its inhibition failed to reverse the impact of MLF1 knockdown. Instead, MLF1-mediated regulation was blunted by inhibiting the acetyltransferase EP300. CUT&Tag analysis showed that MLF1 bound to target promoters and recruited EP300 to promote H3K27ac deposition. Collectively, we identify MLF1 as a pro-aging epigenetic orchestrator that recruits EP300 to facilitate opening of the condensed chromatin encompassing senescence effectors.
| S-EPMC11754730 | biostudies-literature
Project description:Downregulation of MLF1 safeguards cardiomyocytes against senescence-associated chromatin opening
| PRJNA1142575 | ENA
Project description:Functional studies found that knockdown of EP300 ameliorated the drug-induced cellular senescence phenotype. Here, we apply transcriptomics to explore the underlying molecular mechanisms.
2025-01-29 | GSE261096 | GEO
Project description:Chronic cardiotoxicity is less common in male than in female patients receiving doxorubicin and other anthracyclines at puberty and adolescence. We hypothesized that this sex difference might be secondary to distinct activities of sex hormones on cardiomyocyte senescence, which is thought to be central to the development of long-term anthracycline cardiomyopathy.H9c2 cells and neonatal mouse cardiomyocytes were exposed to doxorubicin with or without prior incubation with testosterone or 17β-estradiol, the main androgen and estrogen, respectively. Testosterone, but not 17β-estradiol, counteracted doxorubicin-elicited senescence. Downregulation of telomere binding factor 2, which has been pinpointed previously as being pivotal to doxorubicin-induced senescence, was also prevented by testosterone, as were p53 phosphorylation and accumulation. Pretreatment with the androgen receptor antagonist flutamide, the phosphatidylinositol 3 kinase inhibitor LY294002, and the nitric oxide synthase inhibitor L-NG-nitroarginine methyl ester abrogated the reduction in senescence and the normalization of telomere binding factor 2 levels attained by testosterone. Consistently, testosterone enhanced the phosphorylation of AKT and nitric oxide synthase 3. In H9c2 cells, doxorubicin-stimulated senescence was still observed up to 21 days after treatment and increased further when cells were rechallenged with doxorubicin 14 days after the first exposure to mimic the schedule of anthracycline-containing chemotherapy. Remarkably, these effects were also inhibited by testosterone.Testosterone protects cardiomyocytes against senescence caused by doxorubicin at least in part by modulating telomere binding factor 2 via a pathway involving the androgen receptor, phosphatidylinositol 3 kinase, AKT, and nitric oxide synthase 3. This is a potential mechanism by which pubescent and adolescent boys are less prone to chronic anthracycline cardiotoxicity than girls.
| S-EPMC4859360 | biostudies-other
Project description:Adipose tissue is an important endocrine organ that regulates metabolism, immune response and aging in mammals. Healthy adipocytes promote tissue homeostasis and longevity. SIRT1, a conserved NAD+-dependent deacetylase, negatively regulates adipogenic differentiation by deacetylating and inhibiting PPAR-γ. However, knocking out SIRT1 in mesenchymal stem cells (MSCs) in mice not only causes defects in osteogenesis, but also results in the loss of adipose tissues, suggesting that SIRT1 is also important for adipogenic differentiation.Here, we report that severe impairment of SIRT1 function in MSCs caused significant defects and cellular senescence during adipogenic differentiation. These were observed only when inhibiting SIRT1 during adipogenesis, not when SIRT1 inhibition was imposed before or after adipogenic differentiation. Cells generate high levels of reactive oxygen species (ROS) during adipogenic differentiation. Inhibiting SIRT1 during differentiation resulted in impaired oxidative stress response. Increased oxidative stress with H2O2 or SOD2 knockdown phenocopied SIRT1 inhibition. Consistent with these observations, we found increased p16 levels and senescence associated β-galactosidase activities in the inguinal adipose tissue of MSC-specific SIRT1 knockout mice. Furthermore, previously identified SIRT1 targets involved in oxidative stress response, FOXO3 and SUV39H1 were both required for healthy adipocyte formation during differentiation. Finally, senescent adipocytes produced by SIRT1 inhibition showed decreased Akt phosphorylation in response to insulin, a lack of response to adipocytes browning signals, and increased survival for cancer cells under chemotherapy drug treatments. These findings suggest a novel safeguard function for SIRT1 in regulating MSC adipogenic differentiation, distinct from its roles in suppressing adipogenic differentiation.
| S-EPMC10828476 | biostudies-literature
Project description:Nucleophosmin (NPM1) is either frequently mutated or subjected to chromosomal translocation in acute myeloid leukemia (AML). NPM protein is primarily located in the nucleus, but the recurrent NPMc+ mutation is characterized by cytoplasmic localization and leukemogenic properties. Similarly, the NPM-MLF1 translocation product favors the partial cytoplasmic retention of NPM. Regardless of their common cellular distribution, NPM-MLF1 malignancies engender different effects on hematopoiesis compared to NPMc+ counterparts, highlighting possible aberrant nuclear function(s) of NPM in NPMc+ AML. We performed a proteomics analysis and found that NPM and NPM-MLF1 interact with chromatin remodeling complexes of the ISWI family, as well as with NuRD and P/BAF complexes. Accordingly, NPM and NPM-MLF1 are recruited to transcriptionally active or repressed genes along with NuRD and P/BAF elements. Although the overall gene expression program in NPM knockdown cells is similar to that resulting from NPMc+ and is consistent with loss of nuclear function of NPM, NPM-MLF1 expression differentially altered gene transcription regulated by NPM. The abnormal gene regulation imposed by NPM-MLF1 is characterized by enhanced recruitment of NuRD to gene regulatory regions. Thus, different mechanisms orchestrate the deregulation of NPM function in NPMc+- versus NPM1-MLF1-associated leukemia.
2019-10-17 | GSE124495 | GEO
Project description:Nucleophosmin (NPM1) is either frequently mutated or subjected to chromosomal translocation in acute myeloid leukemia (AML). NPM protein is primarily located in the nucleus, but the recurrent NPMc+ mutation is characterized by cytoplasmic localization and leukemogenic properties. Similarly, the NPM-MLF1 translocation product favors the partial cytoplasmic retention of NPM. Regardless of their common cellular distribution, NPM-MLF1 malignancies engender different effects on hematopoiesis compared to NPMc+ counterparts, highlighting possible aberrant nuclear function(s) of NPM in NPMc+ and NPM-MLF1 AML. We performed a proteomics analysis and found that NPM and NPM-MLF1 interact with chromatin remodeling complexes of the ISWI family, as well as with NuRD and P/BAF complexes. Accordingly, NPM and NPM-MLF1 are recruited to transcriptionally active or repressed genes along with NuRD and P/BAF elements. Although the overall gene expression program in NPM knockdown cells is similar to that resulting from NPMc+ and is consistent with loss of nuclear function of NPM, NPM-MLF1 expression differentially altered gene transcription regulated by NPM. The abnormal gene regulation imposed by NPM-MLF1 is characterized by enhanced recruitment of NuRD to gene regulatory regions. Thus, different mechanisms orchestrate the deregulation of NPM function in NPMc+ -versus NPM1-MLF1- associated leukemia.
2019-10-18 | PXD012305 | Pride
Project description:POLD1, the catalytic subunit of DNA Pol δ, plays an important role in DNA synthesis and DNA damage repair, and POLD1 is downregulated in replicative senescence and mediates cell aging. However, the mechanisms of age-related downregulation of POLD1 expression have not been elucidated. In this study, four potential CpG islands in the POLD1 promoter were found, and the methylation levels of the POLD1 promoter were increased in aging 2BS cells, WI-38 cells and peripheral blood lymphocytes, especially at a single site, CpG 36, in CpG island 3. Then, the transcription factor E2F1 was observed to bind to these sites. The binding affinity of E2F1 for the POLD1 promoter was found to show age-related attenuation and was confirmed to be positively regulated by the E2F1 level and negatively regulated by POLD1 promoter methylation. Moreover, cell senescence characteristics were observed in the cells transfected with shRNA-E2F1 and could contribute to the downregulation of POLD1 induced by the E2F1 decline. Collectively, these results indicated that the attenuation of the binding affinity of E2F1 for the POLD1 promoter, mediated by an age-related decline in E2F1 and increased methylation of CpG island 3, downregulates POLD1 expression in aging.
| S-EPMC6588650 | biostudies-literature