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1.
Cell Commun Signal ; 22(1): 467, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39350161

RESUMO

Traumatic brain injury (TBI) is an acquired insult to the brain caused by an external mechanical force, potentially resulting in temporary or permanent impairment. Microglia, the resident immune cells of the central nervous system, are activated in response to TBI, participating in tissue repair process. However, the underlying epigenetic mechanisms in microglia during TBI remain poorly understood. ARID1A (AT-Rich Interaction Domain 1 A), a pivotal subunit of the multi-protein SWI/SNF chromatin remodeling complex, has received little attention in microglia, especially in the context of brain injury. In this study, we generated a Arid1a cKO mouse line to investigate the potential roles of ARID1A in microglia in response to TBI. We found that glial scar formation was exacerbated due to increased microglial migration and a heightened inflammatory response in Arid1a cKO mice following TBI. Mechanistically, loss of ARID1A led to an up-regulation of the chemokine CCL5 in microglia upon the injury, while the CCL5-neutralizing antibody reduced migration and inflammatory response of LPS-stimulated Arid1a cKO microglia. Importantly, administration of auraptene (AUR), an inhibitor of CCL5, repressed the microglial migration and inflammatory response, as well as the glial scar formation after TBI. These findings suggest that ARID1A is critical for microglial response to injury and that AUR has a therapeutic potential for the treatment of TBI.


Assuntos
Lesões Encefálicas Traumáticas , Quimiocina CCL5 , Proteínas de Ligação a DNA , Camundongos Knockout , Microglia , Fatores de Transcrição , Animais , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/genética , Microglia/metabolismo , Microglia/patologia , Quimiocina CCL5/metabolismo , Quimiocina CCL5/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Camundongos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Movimento Celular , Cicatriz/patologia , Cicatriz/metabolismo , Camundongos Endogâmicos C57BL , Masculino
2.
Ecotoxicol Environ Saf ; 270: 115881, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38147775

RESUMO

BACKGROUND: Wide phthalate exposure has been associated with both declines in renal function and an elevated risk of mortality. Whether phthalate-associated risk of premature mortality differs by renal function status remains unclear. METHODS: This study included 9605 adults from the U.S. National Health and Nutrition Examination Survey. Urinary concentrations of 11 phthalate metabolites were assessed using high-performance liquid chromatography-electrospray ionization tandem mass spectrometry. According to estimated glomerular filtration rate (eGFR), participants were grouped as having normal or modestly declined renal functions, or chronic kidney disease (CKD). Multivariable Cox regression models estimated all-cause mortality associated with phthalate exposure, overall and by renal function status. RESULTS: Overall, Mono-n-butyl phthalate (MnBP), Mono-benzyl phthalate (MBzP), Mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and Mono-(2-ethyl-5-carbox-ypentyl) phthalate (MECPP) were associated with an elevated risk of mortality (P-trend across tertile <0.05). Moreover, significant interactions were observed between eGFR and MEHHP, MEOHP, MECPP, DEHP in the whole population (P for interactions <0.05). After stratification by renal function, total Di (2-ethylhexyl) phthalate (DEHP) was additionally found to be associated with mortality risk in the CKD group (HR = 1.12; 95% CI: 1.01, 1.25). Co-exposure to the 11 phthalate metabolites was associated with a higher risk of all-cause mortality in the CKD (HR = 1.47; 95% CI: 1.18, 1.84) and modestly declined renal function group (HR = 1.25; 95% CI: 1.09, 1.44). CONCLUSIONS: The associations between phthalate exposure and risk of all-cause mortality were primarily observed in CKD patients, reinforcing the need for monitoring phthalate exposure in this patient population.


Assuntos
Dietilexilftalato , Poluentes Ambientais , Ácidos Ftálicos , Insuficiência Renal Crônica , Adulto , Humanos , Exposição Ambiental/análise , Inquéritos Nutricionais , Ácidos Ftálicos/metabolismo , Insuficiência Renal Crônica/induzido quimicamente , Rim/metabolismo , Poluentes Ambientais/análise
3.
Mol Psychiatry ; 27(7): 2999-3009, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35484239

RESUMO

The embryonic ectoderm development (EED) is a core component of the polycomb-repressive complex 2 (PRC2) whose mutations are linked to neurodevelopmental abnormalities, intellectual disability, and neurodegeneration. Although EED has been extensively studied in neural stem cells and oligodendrocytes, its role in microglia is incompletely understood. Here, we show that microglial EED is essential for synaptic pruning during the postnatal stage of brain development. The absence of microglial EED at early postnatal stages resulted in reduced spines and impaired synapse density in the hippocampus at adulthood, accompanied by upregulated expression of phagocytosis-related genes in microglia. As a result, deletion of microglial Eed impaired hippocampus-dependent learning and memory in mice. These results suggest that microglial EED is critical for normal synaptic and cognitive functions during postnatal development.


Assuntos
Microglia , Células-Tronco Neurais , Animais , Hipocampo/metabolismo , Camundongos , Microglia/metabolismo , Células-Tronco Neurais/metabolismo , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo , Sinapses/metabolismo
4.
EMBO Rep ; 22(10): e52023, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34369651

RESUMO

Histone lysine crotonylation (Kcr), an evolutionarily conserved and widespread non-acetyl short-chain lysine acylation, plays important roles in transcriptional regulation and disease processes. However, the genome-wide distribution, dynamic changes, and associations with gene expression of histone Kcr during developmental processes are largely unknown. In this study, we find that histone Kcr is mainly located in active promoter regions, acts as an epigenetic hallmark of highly expressed genes, and regulates genes participating in metabolism and proliferation. Moreover, elevated histone Kcr activates bivalent promoters to stimulate gene expression in neural stem/progenitor cells (NSPCs) by increasing chromatin openness and recruitment of RNA polymerase II (RNAP2). Functionally, these activated genes contribute to transcriptome remodeling and promote neuronal differentiation. Overall, histone Kcr marks active promoters with high gene expression and modifies the local chromatin environment to allow gene activation.


Assuntos
Histonas , Células-Tronco Neurais , Histonas/genética , Histonas/metabolismo , Lisina/metabolismo , Células-Tronco Neurais/metabolismo , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional
5.
Pharmacoepidemiol Drug Saf ; 32(2): 107-125, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36224724

RESUMO

BACKGROUND: Some early reports in the medical literature have raised concern about a possible increased risk of pancreatic cancer associated with the use of two broad classes of incretin-based therapies, dipeptidyl peptidase-4 inhibitors, and glucagon-like peptide-1 receptor agonists. This possibility has been somewhat mitigated by the null findings meta-analyses of randomized controlled trials, but the usefulness of their findings was hampered by serious shortcomings of lack of power and representativeness. These shortcomings can typically be addressed by observational studies, but observational studies on the topic have yielded conflicting findings. A systematic review and meta-analysis of observational studies was performed to qualitatively and quantitatively appraise the totality of evidence on the association between the use of incretin-based therapies and the risk of pancreatic cancer in routine clinical practice. METHODS: The PubMed, Web of Science, Embase, and Google Scholar databases were searched. The study quality was appraised using the ROBINS-I tool and based on the presence of pharmacoepidemiology biases. A random-effects model was used to estimate the summary relative risks with corresponding CIs. RESULTS: A total of 14 studies were included. The qualitative assessment revealed that all studies had inadequate follow-up (≤5 years), 12 studies were suspected to suffer from time-lag bias (due to inappropriate choice of comparator group) to varying extent, five studies included prevalent users, five studies did not implement exposure lag period, five studies had a serious risk of bias due to confounding, and one study had a time-window bias. The quantitative assessment showed no indication of an increased risk when all studies were pooled together (RR 1.04, 95% CI 0.87, 1.24) and when the analysis was restricted to the studies with the least bias (RR 0.77, 95% CI 0.51, 1.17). However, the pooled RRs were more frequently higher in the studies with less rigorous design and analysis. Specifically, a tendency toward an increased risk was observed in the studies with (RR 1.34, 95% CI 1.04, 1.72) or possibly with (RR 1.10, 95% CI 0.89, 1.36) time-lag bias, in the studies that did not apply (RR 1.23, 95% CI 0.93, 1.63) or with potentially inadequate exposure lag period of 6 months (RR 1.13, 95% CI 0.66, 1.94), in the studies that inappropriate comparator group of a combination of unspecified (RR 1.49, 95% CI 1.25, 1.78) or non-insulin (RR 1.15, 95% CI 0.93, 1.42) antidiabetic drugs, and in the studies with serious risk of bias due to confounding (RR 1.18, 95% CI 0.56, 2.49). CONCLUSIONS: In summary, the totality of evidence from observational studies does not support the claim that the use of incretin-based therapies is associated with an increased risk of pancreatic cancer in routine clinical practice. The increased risk of pancreatic cancer observed in observational studies reflects bias resulting from suboptimal methodological approaches, which need to be avoided by future studies.


Assuntos
Inibidores da Dipeptidil Peptidase IV , Neoplasias Pancreáticas , Humanos , Incretinas/efeitos adversos , Hipoglicemiantes/efeitos adversos , Neoplasias Pancreáticas/induzido quimicamente , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Neoplasias Pancreáticas
6.
Glia ; 69(5): 1292-1306, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33492723

RESUMO

Neurotrauma has been recognized as a risk factor for neurodegenerative diseases, and sex difference of the incidence and outcome of neurodegenerative diseases has long been recognized. Past studies suggest that microglia could play a versatile role in both health and disease. So far, the microglial mechanisms underlying neurodegeneration and potentially lead to sex-specific therapies are still very open. Here we applied whole transcriptome analysis of microglia acutely isolated at different timepoints after a cortical stab wound injury to gain insight into genes that might be dysregulated and transcriptionally different between males and females after cortical injury. We found that microglia displayed distinct temporal and sexual molecular signatures of transcriptome after cortical injury. Hypotheses and gene candidates that we presented in the present study could be worthy to be examined to explore the roles of microglia in neurotrauma and in sex-biased neurodegenerative diseases.


Assuntos
Microglia , Doenças Neurodegenerativas , Encéfalo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Doenças Neurodegenerativas/genética , Transcriptoma
7.
Nutr Cancer ; 73(11-12): 2832-2841, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33356605

RESUMO

The Geriatric Nutritional Risk Index (GNRI) is widely applied as a prognostic factor in different cancers. We aimed to analyze the prognostic value of the GNRI in 257 patients diagnosed with advanced non-small-cell lung cancer (NSCLC). Patients with GNRI >98, 92-98, and <92 were grouped into normal, low risk and moderate/high risk groups, respectively. There were 45.1% patients at risk for malnutrition. Kaplan-Meier survival curves indicated that patients with lower GNRI scores had a poorer overall survival (OS). Two-year OS for normal, low risk and moderate/high risk groups were 57.4%, 42.3% and 15.8%, respectively. In multivariate survival analysis, GNRI (<92), body mass index (BMI, ≥24 kg/m2), combined therapy, hemoglobin and neutrophil-to-lymphocyte ratio (NLR) were independent prognostic factors of OS. Stratifying by age groups, GNRI (<92), hemoglobin and NLR were independent prognostic factors of OS in patients aged <65 years. GNRI (<92), smoking, BMI (≥24 kg/m2) and platelet-to-lymphocyte ratio were independent prognostic factors of OS in patients aged ≥65 years. In conclusion, GNRI was a significant prognostic factor in advanced NSCLC patients regardless of age. A decreased GNRI may be considered as a clinical trigger for nutritional support in advanced NSCLC patients, though additional studies are still required to confirm the best cut-point.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Desnutrição , Idoso , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Avaliação Nutricional , Estado Nutricional , Prognóstico , Estudos Retrospectivos , Fatores de Risco
8.
Food Funct ; 15(14): 7567-7576, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38934729

RESUMO

Background: Gout is a nutrition-related, highly prevalent inflammatory arthritis with undesirable effects on the quality of life. The relationships between circulating fatty acids (FAs) and gout remain poorly understood. Method: We included 268 174 participants with plasma FAs measured using nuclear magnetic resonance at the baseline (2006-2010) from the UK Biobank, of which 15 194 participants had repeated measures of FAs between 2012 and 2013. Cox proportional hazards models were used to assess the association of the baseline and longitudinal changes in relative levels of plasma FAs (% total FAs) with incident gout. Mendelian randomization (MR) analyses were conducted to assess the potential causality of the examined association. Results: Over a median follow-up of 12.8 years, 5160 incident cases of gout occurred. Baseline polyunsaturated fatty acids (PUFAs), n-6 PUFAs, and linoleic acids (LAs) were inversely associated with incident gout (all P-trend values < 0.0001). Baseline monounsaturated fatty acids (MUFAs), n-3 PUFAs, and docosahexaenoic acids (DHAs) were positively associated with incident gout (all P-trend values < 0.0001). Longitudinal increments of n-6 PUFAs and LAs were associated with a lower risk of subsequent gout, whereas an increment of n-3 PUFAs was associated with a higher risk. In two-sample MR analyses, genetically determined higher levels of PUFAs, n-6 PUFAs, and LAs were associated with a decreased risk of gout (all P values < 0.05). Conclusions: Our findings consistently indicate a causal relationship of elevated levels of n-6 PUFAs, especially LAs, with a reduced risk of gout.


Assuntos
Gota , Ácido Linoleico , Humanos , Gota/epidemiologia , Gota/sangue , Gota/genética , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Risco , Idoso , Ácido Linoleico/sangue , Adulto , Estudos de Coortes , Análise da Randomização Mendeliana , Reino Unido/epidemiologia , Ácidos Graxos Insaturados/sangue
9.
Cell Rep Med ; 5(5): 101554, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38729157

RESUMO

The axons of retinal ganglion cells (RGCs) form the optic nerve, transmitting visual information from the eye to the brain. Damage or loss of RGCs and their axons is the leading cause of visual functional defects in traumatic injury and degenerative diseases such as glaucoma. However, there are no effective clinical treatments for nerve damage in these neurodegenerative diseases. Here, we report that LIM homeodomain transcription factor Lhx2 promotes RGC survival and axon regeneration in multiple animal models mimicking glaucoma disease. Furthermore, following N-methyl-D-aspartate (NMDA)-induced excitotoxicity damage of RGCs, Lhx2 mitigates the loss of visual signal transduction. Mechanistic analysis revealed that overexpression of Lhx2 supports axon regeneration by systematically regulating the transcription of regeneration-related genes and inhibiting transcription of Semaphorin 3C (Sema3C). Collectively, our studies identify a critical role of Lhx2 in promoting RGC survival and axon regeneration, providing a promising neural repair strategy for glaucomatous neurodegeneration.


Assuntos
Axônios , Modelos Animais de Doenças , Glaucoma , Proteínas com Homeodomínio LIM , Regeneração Nervosa , Células Ganglionares da Retina , Fatores de Transcrição , Animais , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Proteínas com Homeodomínio LIM/metabolismo , Proteínas com Homeodomínio LIM/genética , Glaucoma/genética , Glaucoma/patologia , Glaucoma/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Axônios/metabolismo , Axônios/patologia , Camundongos , Regeneração Nervosa/genética , Regeneração Nervosa/fisiologia , Camundongos Endogâmicos C57BL , Sobrevivência Celular/genética , Semaforinas/metabolismo , Semaforinas/genética , N-Metilaspartato/metabolismo
10.
Food Funct ; 15(8): 4223-4232, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517343

RESUMO

Background: A healthy eating pattern characterized by a higher intake of healthy plant foods has been associated with a lower risk of premature mortality, but whether this applies to individuals with varying glycemic status remains unclear. Methods: This study included 4621 participants with diabetes and 8061 participants with prediabetes from the US National Health and Nutrition Examination Survey (2007-2016). Using the dietary data assessed by two 24 h dietary recalls, a healthful plant-based diet index (hPDI) and an unhealthful plant-based diet index (uPDI) were created based on 15 food groups and were assessed for their relationships with mortality risk. Results: Over a median follow-up of 7.2 years, there were 1021 deaths in diabetes and 896 deaths in prediabetes. A higher hPDI (highest vs. lowest quartile) was associated with a 41% (HR = 0.59, 95% CI: 0.49-0.72; P-trend < 0.001) lower risk of all-cause mortality in diabetes and a 31% (HR = 0.69, 95% CI: 0.55-0.85; P-trend < 0.001) lower risk in prediabetes. A higher uPDI was associated with an 88% (HR = 1.88, 95% CI: 1.55-2.28; P-trend < 0.001) higher risk of mortality in diabetes and a 63% (HR = 1.63, 95% CI: 1.33-1.99; P-trend < 0.001) higher risk in prediabetes. Mediation analysis suggested that C-reactive protein and γ-glutamine transaminase explained 6.0% to 10.9% of the relationships between hPDI or uPDI and all-cause mortality among participants with diabetes. Conclusions: For adults with diabetes as well as those with prediabetes, adhering to a plant-based diet rich in healthier plant foods is associated with a lower mortality risk, whereas a diet that incorporates less healthy plant foods is associated with a higher mortality risk.


Assuntos
Biomarcadores , Diabetes Mellitus , Dieta Baseada em Plantas , Inquéritos Nutricionais , Estado Pré-Diabético , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores/sangue , Diabetes Mellitus/mortalidade , Estado Pré-Diabético/mortalidade , Fatores de Risco , Estados Unidos/epidemiologia
11.
Cell Death Differ ; 30(8): 1943-1956, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37433907

RESUMO

The ability of neural stem/progenitor cells (NSPCs) to proliferate and differentiate is required through different stages of neurogenesis. Disturbance in the regulation of neurogenesis causes many neurological diseases, such as intellectual disability, autism, and schizophrenia. However, the intrinsic mechanisms of this regulation in neurogenesis remain poorly understood. Here, we report that Ash2l (Absent, small or homeotic discs-like 2), one core component of a multimeric histone methyltransferase complex, is essential for NSPC fate determination during postnatal neurogenesis. Deletion of Ash2l in NSPCs impairs their capacity for proliferation and differentiation, leading to simplified dendritic arbors in adult-born hippocampal neurons and deficits in cognitive abilities. RNA sequencing data reveal that Ash2l primarily regulates cell fate specification and neuron commitment. Furthermore, we identified Onecut2, a major downstream target of ASH2L characterized by bivalent histone modifications, and demonstrated that constitutive expression of Onecut2 restores defective proliferation and differentiation of NSPCs in adult Ash2l-deficient mice. Importantly, we identified that Onecut2 modulates TGF-ß signaling in NSPCs and that treatment with a TGF-ß inhibitor rectifies the phenotype of Ash2l-deficient NSPCs. Collectively, our findings reveal the ASH2L-Onecut2-TGF-ß signaling axis that mediates postnatal neurogenesis to maintain proper forebrain function.


Assuntos
Células-Tronco Neurais , Neurogênese , Transdução de Sinais , Animais , Camundongos , Células-Tronco Neurais/metabolismo , Neurogênese/fisiologia , Neurônios/metabolismo , Fator de Crescimento Transformador beta/metabolismo
12.
Cells ; 12(4)2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36831225

RESUMO

Traumatic brain injury usually results in neuronal loss and cognitive deficits. Promoting endogenous neurogenesis has been considered as a viable treatment option to improve functional recovery after TBI. However, neural stem/progenitor cells (NSPCs) in neurogenic regions are often unable to migrate and differentiate into mature neurons at the injury site. Transglutaminase 2 (TGM2) has been identified as a crucial component of neurogenic niche, and significantly dysregulated after TBI. Therefore, we speculate that TGM2 may play an important role in neurogenesis after TBI, and strategies targeting TGM2 to promote endogenous neural regeneration may be applied in TBI therapy. Using a tamoxifen-induced Tgm2 conditional knockout mouse line and a mouse model of stab wound injury, we investigated the role and mechanism of TGM2 in regulating hippocampal neurogenesis after TBI. We found that Tgm2 was highly expressed in adult NSPCs and up-regulated after TBI. Conditional deletion of Tgm2 resulted in the impaired proliferation and differentiation of NSPCs, while Tgm2 overexpression enhanced the abilities of self-renewal, proliferation, differentiation, and migration of NSPCs after TBI. Importantly, injection of lentivirus overexpressing TGM2 significantly promoted hippocampal neurogenesis after TBI. Therefore, TGM2 is a key regulator of hippocampal neurogenesis and a pivotal therapeutic target for intervention following TBI.


Assuntos
Lesões Encefálicas Traumáticas , Neurogênese , Proteína 2 Glutamina gama-Glutamiltransferase , Animais , Camundongos , Lesões Encefálicas Traumáticas/fisiopatologia , Hipocampo/citologia , Hipocampo/metabolismo , Camundongos Knockout , Células-Tronco Neurais , Proteína 2 Glutamina gama-Glutamiltransferase/metabolismo
13.
Cell Prolif ; 56(9): e13439, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36878712

RESUMO

Microglia are the primary source of transglutaminase 2 (TGM2) in the brain; however, the roles of microglial TGM2 in neural development and disease are still not well known. The aim of this study is to elucidate the role and mechanisms of microglial TGM2 in the brain. A mouse line with a specific knockout of Tgm2 in microglia was generated. Immunohistochemistry, Western blot and qRT-PCR assays were performed to evaluate the expression levels of TGM2, PSD-95 and CD68. Confocal imaging, immunofluorescence staining and behavioural analyses were conducted to identify phenotypes of microglial TGM2 deficiency. Finally, RNA sequencing, qRT-PCR and co-culture of neurons and microglia were used to explore the potential mechanisms. Deletion of microglial Tgm2 causes impaired synaptic pruning, reduced anxiety and increased cognitive deficits in mice. At the molecular level, the phagocytic genes, such as Cq1a, C1qb and Tim4, are significantly down-regulated in TGM2-deficient microglia. This study elucidates a novel role of microglial TGM2 in regulating synaptic remodelling and cognitive function, indicating that microglia Tgm2 is essential for proper neural development.


Assuntos
Microglia , Proteína 2 Glutamina gama-Glutamiltransferase , Camundongos , Animais , Microglia/metabolismo , Neurônios/metabolismo , Encéfalo , Cognição
14.
Cell Prolif ; 55(11): e13314, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35854653

RESUMO

OBJECTIVE: Microglia, the prototypical innate immune cells of the central nervous system (CNS), are highly plastic and assume their phenotypes dependent on intrinsically genetic, epigenetic regulation or extrinsically microenvironmental cues. Microglia has been recognized as key regulators of neural stem/progenitor cells (NSPCs) and brain functions. Chromatin accessibility is implicated in immune cell development and functional regulation. However, it is still unknown whether and how chromatin remodelling regulates the phenotypic plasticity of microglia and exerts what kind of effects on NSPCs. METHODS: We investigated the role of chromatin accessibility in microglia by deleting chromatin remodelling gene Arid1a using microglia-specific Cx3cr1-cre and Cx3cr1-CreERT2 mice. RNA-seq and ATAC-seq were performed to dissect the molecular mechanisms. In addition, we examined postnatal M1/M2 microglia polarization and analysed neuronal differentiation of NSPCs. Finally, we tested the effects of microglial Arid1a deletion on mouse behaviours. RESULTS: Increased chromatin accessibility upon Arid1a ablation resulted in enhanced M1 microglial polarization and weakened M2 polarization, which led to abnormal neurogenesis and anxiety-like behaviours. Switching the polarization state under IL4 stimulation could rescue abnormal neurogenesis, supporting an essential role for chromatin remodeler ARID1A in balancing microglial polarization and brain functions. CONCLUSIONS: Our study identifies ARID1A as a central regulator of microglia polarization, establishing a mechanistic link between chromatin remodelling, neurogenesis and mouse behaviours, and highlights the potential development of innovative therapeutics exploiting the innate regenerative capacity of the nervous system.


Assuntos
Microglia , Células-Tronco Neurais , Camundongos , Animais , Epigênese Genética , Neurogênese , Células-Tronco Neurais/fisiologia , Cromatina , Proteínas de Ligação a DNA/genética , Fatores de Transcrição/genética
15.
Cells ; 11(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36291199

RESUMO

The authors wish to make the following changes to their paper [...].

16.
Cells ; 11(8)2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35456028

RESUMO

Overcoming the lack of drugs for the treatment of traumatic brain injury (TBI) has long been a major challenge for the pharmaceutical industry. MiRNAs have emerged as potential targets for progress assessment and intervention against TBI. The brain-enriched miRNA let-7i has been proposed as an ideal candidate biomarker for TBI, but its regulatory roles in brain injury remain largely unknown. Here, we find that the expression of let-7i is significantly downregulated in the early stages of a hippocampal stab wound injury. The noninvasive intranasal administration of let-7i agomir significantly improves cognitive function and suppresses neuroinflammation, glial scar formation, and neuronal apoptosis in TBI mice. Mechanically, STING is a direct downstream target of let-7i after brain injury. Furthermore, the intranasal delivery of let-7i agomir can also effectively inhibit STING and is beneficial for inflammation resolution and neuronal survival in a mouse model of pial vessel disruption stroke. Consequently, let-7i agomir is a promising candidate for clinical application as a chemically engineered oligonucleotides-based therapeutic for brain injury.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , MicroRNAs , Administração Intranasal , Animais , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Cognição , Camundongos , MicroRNAs/metabolismo
17.
Stem Cell Reports ; 17(9): 2064-2080, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-35931079

RESUMO

Mutations in the embryonic ectoderm development (EED) cause Weaver syndrome, but whether and how EED affects embryonic brain development remains elusive. Here, we generated a mouse model in which Eed was deleted in the forebrain to investigate the role of EED. We found that deletion of Eed decreased the number of upper-layer neurons but not deeper-layer neurons starting at E16.5. Transcriptomic and genomic occupancy analyses revealed that the epigenetic states of a group of cortical neurogenesis-related genes were altered in Eed knockout forebrains, followed by a decrease of H3K27me3 and an increase of H3K27ac marks within the promoter regions. The switching of H3K27me3 to H3K27ac modification promoted the recruitment of RNA-Pol2, thereby enhancing its expression level. The small molecule activator SAG or Ptch1 knockout for activating Hedgehog signaling can partially rescue aberrant cortical neurogenesis. Taken together, we proposed a novel EED-Gli3-Gli1 regulatory axis that is critical for embryonic brain development.


Assuntos
Encéfalo , Neurogênese , Complexo Repressor Polycomb 2 , Proteína GLI1 em Dedos de Zinco , Proteína Gli3 com Dedos de Zinco , Animais , Encéfalo/crescimento & desenvolvimento , Epigênese Genética , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Histonas/metabolismo , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Neurogênese/genética , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo , Proteína GLI1 em Dedos de Zinco/genética , Proteína GLI1 em Dedos de Zinco/metabolismo , Proteína Gli3 com Dedos de Zinco/genética , Proteína Gli3 com Dedos de Zinco/metabolismo
18.
EMBO Mol Med ; 14(12): e15795, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36385502

RESUMO

Mutations in AT-rich interactive domain-containing protein 1A (ARID1A) cause Coffin-Siris syndrome (CSS), a rare genetic disorder that results in mild to severe intellectual disabilities. However, the biological role of ARID1A in the brain remains unclear. In this study, we report that the haploinsufficiency of ARID1A in excitatory neurons causes cognitive impairment and defects in hippocampal synaptic transmission and dendritic morphology in mice. Similarly, human embryonic stem cell-derived excitatory neurons with deleted ARID1A exhibit fewer dendritic branches and spines, and abnormal electrophysiological activity. Importantly, supplementation of acetate, an epigenetic metabolite, can ameliorate the morphological and electrophysiological deficits observed in mice with Arid1a haploinsufficiency, as well as in ARID1A-null human excitatory neurons. Mechanistically, transcriptomic and ChIP-seq analyses demonstrate that acetate supplementation can increase the levels of H3K27 acetylation at the promoters of key regulatory genes associated with neural development and synaptic transmission. Collectively, these findings support the essential roles of ARID1A in the excitatory neurons and cognition and suggest that acetate supplementation could be a potential therapeutic intervention for CSS.


Assuntos
Acetatos , Proteínas de Ligação a DNA , Haploinsuficiência , Deficiência Intelectual , Fatores de Transcrição , Animais , Humanos , Camundongos , Acetatos/farmacologia , Acetatos/uso terapêutico , Cognição/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Fatores de Transcrição/genética , Transcriptoma , Neurônios/efeitos dos fármacos , Deficiência Intelectual/tratamento farmacológico
19.
Biochem Biophys Res Commun ; 407(1): 1-6, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21316338

RESUMO

Gemcitabine has been a first-line chemotherapy agent for advanced pancreatic cancer, which is associated with one of the lowest 5 years survival rates among human cancers. Due to our lack of understanding of the genetic determinants of Gemcitabine sensitivity in pancreatic cancer, the therapeutic effectiveness of Gemcitabine chemotherapy is typically unpredictable. Using a genome-wide and piggyBac transposon-based genetic screening platform, we identified the PVT1 gene as a regulator of Gemcitabine sensitivity and showed that functional inactivation of the PVT1 gene led to enhanced Gemcitabine sensitivity in human pancreatic cancer ASPC-1 cells. The integration of the piggyBac transposon-based vector system into intron 3 of PVT1 was within a common site of oncogenic retroviral insertions and chromosomal translocations. PVT1 is a non-protein encoding gene; the genomic arrangement of PVT1 and its co-amplification with MYC have been implicated in the tumorigenesis of a variety of cancers. The molecular mechanism of PVT1 transcripts in gene regulation remains a puzzle. We demonstrated that overexpression of a full length PVT1 cDNA in the antisense orientation reconstituted enhanced sensitivity to Gemcitabine in naïve ASPC-1 cells, whereas overexpression of a full length PVT1 cDNA in the sense orientation resulted in decreased sensitivity to Gemcitabine. Our results identified PVT1 as a regulator of Gemcitabine sensitivity in pancreatic cancer cells and validated the genome-wide genetic screening approach for the identification of genetic determinants as well as potential biomarkers for the rational design of Gemcitabine chemotherapies for pancreatic cancer.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/genética , Estudo de Associação Genômica Ampla/métodos , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas/genética , Antimetabólitos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Clonagem Molecular , Elementos de DNA Transponíveis/genética , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Humanos , Mutagênese , Neoplasias Pancreáticas/genética , RNA Longo não Codificante , Gencitabina
20.
Stem Cell Reports ; 15(2): 439-453, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32679064

RESUMO

UTX, a H3K27me3 demethylase, plays an important role in mouse brain development. However, so little is known about the function of UTX in human neural differentiation and dendritic morphology. In this study, we generated UTX-null human embryonic stem cells using CRISPR/Cas9, and differentiated them into neural progenitor cells and neurons to investigate the effects of UTX loss of function on human neural development. The results showed that the number of differentiated neurons significantly reduced after loss of UTX, and that the dendritic morphology of UTX KO neurons tended to be simplified. The electrophysiological recordings showed that most of the UTX KO neurons were immature. Finally, RNA sequencing identified dozens of differentially expressed genes involved in neural differentiation and synaptic function in UTX KO neurons and our results demonstrated that UTX regulated these critical genes by resolving bivalent promoters. In summary, we establish a reference for the important role of UTX in human neural differentiation and dendritic morphology.


Assuntos
Diferenciação Celular/genética , Dendritos/metabolismo , Histona Desmetilases/metabolismo , Regiões Promotoras Genéticas , Sequência de Bases , Linhagem Celular , Linhagem da Célula/genética , Autorrenovação Celular , Fenômenos Eletrofisiológicos , Histonas/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Lisina/metabolismo , Metilação , Neuritos/metabolismo , Transcrição Gênica , Regulação para Cima/genética
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