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1.
Actual. osteol ; 16(1): 47-66, Ene - abr. 2020. ilus
Article in Spanish | LILACS | ID: biblio-1140035

ABSTRACT

La "razón de ser" de nuestros huesos y esqueletos constituye un dilema centralizado en los conceptos biológicos de "estructura" y "organización", cuya solución necesitamos comprender para interpretar, diagnosticar, tratar y monitorear correctamente las osteopatías fragilizantes. Últimamente se ha reunido conocimiento suficiente para proponer aproximaciones razonables a ese objetivo. La que exponemos aquí requiere la aplicación de no menos de 6 criterios congruentes: 1) Un criterio cosmológico, que propone un origen común para todas las cosas; 2) Un criterio biológico, que explica el origen común de todos los huesos; 3) Un enfoque epistemológico, que desafía nuestra capacidad de comprensión del concepto concreto de estructura y del concepto abstracto de organización, focalizada en la noción rectora de direccionalidad espacial; 4) Una visión ecológica, que destaca la importancia del entorno mecánico de cada organismo para la adecuación de la calidad mecánica de sus huesos a las "funciones de sostén" que les adjudicamos; 5) Una correlación entre todo ese conocimiento y el necesario para optimizar nuestra aptitud para resolver los problemas clínicos implicados y 6) Una jerarquización del papel celular en el manejo de las interacciones genético-ambientales necesario para asimilar todo el problema a una simple cuestión de organización direccional de la estructura de cada hueso. Solo aplicando estos 6 criterios estaríamos en condiciones de responder a la incógnita planteada por el título. La conclusión de esta interpretación de la conducta y función de los huesos debería afectar el fundamento de la mayoría de las indicaciones farmacológicas destinadas al tratamiento de la fragilidad ósea. (AU)


The nature of the general behavior of our bones as weight-bearing structures is a matter of two biological concepts, namely, structure and organization, which are relevant to properly interpret, diagnose, treat, and monitor all boneweakening diseases. Different approaches can be proposed to trace the corresponding relationships. The one we present here involves six congruent criteria, namely, 1) a cosmological proposal of a common origin for everything; 2) a biological acknowledgement of a common origin for all bones; 3) the epistemological questioning of our understanding of the concrete concept of structure and the abstract notion of organization, focused on the lead idea of directionality; 4) the ecological insight that emphasizes the relevance of the mechanical environment of every organism to the naturally-selected adjustment of the mechanical properties of their mobile bones to act as struts or levers; 5) The clinical aspects of all the alluded associations; 6) The central role of bone cells to control the genetics/ environment interactions of any individual as needed to optimize the directionality of the structure of each of his/her bones to keep their mechanical ability within physiological limits. From our point of view, we could only solve the riddle posed by the title by addressing all of these six criteria. The striking conclusion of our analysis suggests that the structure (not the mass) of every bone would be controlled not only to take care of its mechanical ability, but also to cope with other properties which show a higher priority concerning natural selection. The matter would be that this interpretation of bone behavior and 'function' should affect the rationales for most pharmacological indications currently made to take care of bone fragility. (AU)


Subject(s)
Humans , Bone and Bones/physiology , Bone Diseases, Metabolic/diagnosis , Osteogenesis Imperfecta/diagnosis , Osteogenesis Imperfecta/therapy , Osteoporosis/diagnosis , Osteoporosis/therapy , Bone and Bones/anatomy & histology , Bone and Bones/cytology , Bone and Bones/ultrastructure , Bone Diseases, Metabolic/therapy , Epigenesis, Genetic
2.
Article in Chinese | WPRIM | ID: wpr-828538

ABSTRACT

Iron homeostasis plays an important role for the maintenance of human health. It is known that iron metabolism is tightly regulated by several key genes, including divalent metal transport-1(), transferrin receptor 1(), transferrin receptor 2(), ferroportin(), hepcidin(), hemojuvelin() and . Recently, it is reported that DNA methylation, histone acetylation, and microRNA (miRNA) epigenetically regulated iron homeostasis. Among these epigenetic regulators, DNA hypermethylation of the promoter region of , and bone morphogenetic protein 6 () genes result in inhibitory effect on the expression of these iron-related gene. In addition, histone deacetylase (HADC) suppresses gene expression. On the contrary, HADC inhibitor upregulates gene expression. Additional reports showed that miRNA can also modulate iron absorption, transport, storage and utilization via downregulation of and other genes. It is noteworthy that some key epigenetic regulatory enzymes, such as DNA demethylase TET2 and histone lysine demethylase JmjC KDMs, require iron for the enzymatic activities. In this review, we summarize the recent progress of DNA methylation, histone acetylation and miRNA in regulating iron metabolism and also discuss the future research directions.


Subject(s)
Epigenesis, Genetic , Gene Expression Regulation , Genetics , Homeostasis , Humans , Iron , Metabolism , Receptors, Transferrin
3.
Article in Chinese | WPRIM | ID: wpr-827181

ABSTRACT

OBJECTIVE@#To analyze the genome-wide DNA methylation differences in umbilical cord blood nucleated red blood cells (NRBCs) between term and preterm infants by using the methylation gene chip technology, and to screen the genes of differential methylation and biological signaling pathways which may be related to the expression of γ-globin gene (HBG).@*METHODS@#Umbilical cord bloods of eight term infants and eight preterm infants were collected, and NRBCs of each sample was isolated, then genome DNA was extracted and bisulfite conversion was performed. The DNA methylation sites were detected by using the Illumina 850K BeadChip. Differential DNA methylation sites were screened, and the function of genes with differential methylation was analyzed by using GO and KEGG enrichment analysis.@*RESULTS@#Compared with the preterm group, 4749 differential DNA methylation sites of term group were screened out, including 4359 hypomethylation sites and 390 hypermethylation sites. GO and KEGG analysis indicated that the function of genes with differential methylation mainly involved in the hemopoietic system, growth and development process, Wnt and Notch signal pathways.@*CONCLUSION@#The differentical methylation sites at genome-wide level in umbilicar cord blood NRBC of term and preterm infants have been obtained, and the signal pathway and genes which possibily related with swiching the expression of γ-globin gene to β-globin gene have been screened-out. This study provide the new targets for studing the mechamism regulating expression of HBG gene.


Subject(s)
DNA , DNA Methylation , Epigenesis, Genetic , Fetal Blood , Genome, Human , Humans , Infant, Newborn , Infant, Premature
4.
Acta Physiologica Sinica ; (6): 506-512, 2020.
Article in Chinese | WPRIM | ID: wpr-827036

ABSTRACT

Alzheimer's disease (AD) is currently the most prevalent neurodegenerative disease in the aging population. It is characterized by massive deposition of extracellular β-amyloid peptide and formation of intracellular neurofibrillary tangles. Cancer is also an age-related disease. Some epidemiological studies have shown an inverse relationship between AD and the onset of various types of cancers, that is, the risk of cancer in patients with AD is reduced, and vice versa. Epigenetic mechanisms play important roles in the development of AD and cancer. In this article, we will review the recent research advances on the epigenetic mechanisms of AD and cancer onset, and provide new ideas for rethinking the relevance of AD and cancer with a "holistic concept".


Subject(s)
Aged , Alzheimer Disease , Epigenesis, Genetic , Humans , Neoplasms , Neurodegenerative Diseases , Neurofibrillary Tangles
5.
Chinese Journal of Biotechnology ; (12): 838-848, 2020.
Article in Chinese | WPRIM | ID: wpr-826892

ABSTRACT

DNA methylation is an epigenetic modification that forms an important regulation mechanism of gene expression in organisms across kingdoms. Aberrant patterns of DNA methylation can lead to plant developmental abnormalities. In this article, we briefly discuss DNA methylation in plants and summarize its functions and biological roles in regulating gene expression and maintaining genomic stability, plant development, as well as plant responses to biotic and abiotic stresses. We intended to provide a concise reference for further understanding of the mechanism of DNA methylation and potential applications of epigenetic manipulation for crop improvement.


Subject(s)
Crop Production , DNA Methylation , Epigenesis, Genetic , Gene Expression Regulation, Plant , Genomic Instability , Plants , Genetics , Research , Stress, Physiological
7.
Electron. j. biotechnol ; 41: 22-29, sept. 2019. ilus
Article in English | LILACS | ID: biblio-1087255

ABSTRACT

We highlight the importance of the mixed genetic approaches (classical and currents) to improve the social perception related to the GMOs acceptance. We pointed out that CRISPR/Cas9 events could carry DNA variability/rearrangements related to somaclonal variations or epigenetic changes that are independent from the editing per se. The transformation of single cells, followed by plant regeneration, is used to generate modified plants, transgenic or genome editing (CRISPR/Cas9). The incidence of undesirable somaclonal variations and/or epigenetic changes that might have occurred during in vitro multiplication and regeneration processes, must be carefully analyzed in replicates in field trials. One remarkable challenge is related to the time lapse that selects the modified elite genotypes, because these strategies may spend a variable amount of time before the results are commercialized, where in all the cases it should be take into account the genotype × environment interactions. Furthermore, this combination of techniques can create an encouraging bridge between the public opinion and the community of geneticists who are concerned with plant genetic improvement. In this context, either transgenesis or genomic editing strategies become complementary modern tools to facing the challenges of plant genetic improvement. Their applications will depend on case-by-case analysis, and when possible will necessary associate them to the schemes and bases of classic plant genetic improvement.


Subject(s)
Plants, Genetically Modified , Gene Transfer Techniques , CRISPR-Cas Systems , Gene Editing , Transformation, Genetic , Mutagenesis , DNA Methylation , Genetic Enhancement , Epigenesis, Genetic
10.
Article in Chinese | WPRIM | ID: wpr-813281

ABSTRACT

DNA methylation is a significant epigenetic modification mode, which plays an important role in embryo reprogramming, stem cell differentiation and tumor occurrence. The ten-eleven translocation (TET) enzyme is a crucial demethylation enzyme, which can catalyze 5-methylcytosine(5mC) to 5-hydroxymethylcytosine(5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine(5caC). These bases represent the epigenetic modifications of DNA and regulate the process of DNA methylation. Understanding the role of TET enzyme in regulating the DNA methylation modification and gene expression can help us to gain the knowledge for the normal growth development and epigenetic regulation in human diseases.


Subject(s)
5-Methylcytosine , Metabolism , Cell Differentiation , DNA , DNA Methylation , DNA-Binding Proteins , Epigenesis, Genetic , Humans
11.
Article in Chinese | WPRIM | ID: wpr-813229

ABSTRACT

Colorectal cancer is one of the common malignant tumors, which seriously threatens human health. Its morbidity and mortality rank the third and the second among all malignant tumors. The progress of colorectal cancer is a complex process involving the accumulation of genetic and epigenetic changes. Epigenetic changes of colorectal cancer mainly include DNA methylation, histone modification, non-coding RNAs (such as microRNAs and lncRNAs), which are of great significance to early diagnosis and prognosis evaluation, and to chemosensitivity assessment for colorectal cancer, providing a new thought for the treatment of colorectal cancer.


Subject(s)
Colorectal Neoplasms , Genetics , DNA Methylation , Epigenesis, Genetic , Epigenomics , Histones , Humans
12.
Journal of Experimental Hematology ; (6): 2014-2018, 2019.
Article in Chinese | WPRIM | ID: wpr-781502

ABSTRACT

Epigenetic abnormalities play an important role in the pathogenesis of hematological malignancies, especially acute leukemia (AL). Similar to DNA methylation and histone modifications, RNA methylation is another important epigenetic modification. m6A methylation is one of the most prevalent and extensively studied RNA methylation. m6A methylation is involved in many biological and pathological process. Recent studies have found that m6A methylation is involved in the occurrence, development and drug-resistance of AL. This review focuses on the research progress of m6A methylation in AL.


Subject(s)
DNA Methylation , Epigenesis, Genetic , Humans , Leukemia
13.
Journal of Experimental Hematology ; (6): 1711-1716, 2019.
Article in Chinese | WPRIM | ID: wpr-781408

ABSTRACT

Abstract  The physiological hematopoiesis depends on the programmed expression of a series of gene regulated by mechanisms at various levels. Currently, the epigenetic regulation has been considered as the most important mechanism during hematopoietic differentiation, resulting in a specific epigenomic landscape in the hematopoietic stem/progenitor cells. We try to concisely review the epigenetic mechanisms, including the genomic methylation, the histone modifications and the expression profiles of noncoding RNA, illustrating briefly the differentiation from the hematopoietic stem/progenitor cells to to the erythroid, myeloid and lymphoid cells.


Subject(s)
Cell Differentiation , Epigenesis, Genetic , Epigenomics , Hematopoiesis , Hematopoietic Stem Cells
14.
Chinese Journal of Biotechnology ; (12): 142-149, 2019.
Article in Chinese | WPRIM | ID: wpr-771392

ABSTRACT

Tet2 (member 2 of the Tet family) plays an important role in DNA demethylation modification, epigenetic regulation, and hematopoiesis. In our previous study, we found that Tet2 knockout mice progressively developed lymphocytic leukemia and myeloid leukemia with aging. However,the role of Tet2 in bone marrow microenvironment is unclear. Here in this study, we found that more Tet2-/- mesenchymal stem cells (MSCs) from bone marrow were in the G2/M cell cycle stages. The division time of Tet2-/- MSCs was shorter than that of the control cells. The growth rate of Tet2-/- MSCs was accelerated. The cobblestone area-forming cells assay (CAFC) showed that Tet2 knockout MSCs supported the expansion of hematopoietic stem cells (HSCs) and the differentiation of HSCs was skewed towards myeloid cells. Through the dot blotting experiment, we found that the total methylation level was increased in Tet2-/- bone marrow cells (BM). We used the methylation-chip to analyze the methylation level of Tet2-/- bone marrow cells and found that the level of methylation was increased in the transcriptional starting area (TSS), exons (EXONS) and 3' untranslated region (3' UTR). Moreover, we found that the cytokines secreted by Tet2-/- MSCs, such as IL-8 and IL-18, were decreased. While the expressions of GM-CSF and CCL-3, which supported hematopoietic stem cells to differentiate to myeloid cells, were increased in Tet2-/- MSCs. Our results demonstrated that Tet2 regulates MSCs to support hematopoiesis.


Subject(s)
Animals , Bone Marrow Cells , Cell Differentiation , DNA-Binding Proteins , Epigenesis, Genetic , Hematopoiesis , Hematopoietic Stem Cells , Mesenchymal Stem Cells , Mice , Proto-Oncogene Proteins
15.
Chinese Journal of Biotechnology ; (12): 775-783, 2019.
Article in Chinese | WPRIM | ID: wpr-771332

ABSTRACT

Messenger RNA (mRNA) can be modified by more than 100 chemical modifications. Among these modifications, N6-methyladenosine (m⁶A) is one of the most prevalent modifications. During the processes of cells differentiation, embryo development or stress, m⁶A can be modified on key mRNAs and regulate the progress of cells through modulating mRNA metabolism and translation. Other mRNA modifications, including N1-methyladenosine (m¹A), 5-methylcytosine (m⁵C) and pseudouridine, together with m⁶A form the epitranscriptome of mRNA that accurately modulate the mRNA translation. Here we review the types and characteristic of mRNA epigenetic modifications, especially the recent progresses of the function of m⁶A, we also expect the main research direction of m⁶A epigenetic modification in the future.


Subject(s)
Adenosine , Genetics , Metabolism , Cell Differentiation , Genetics , Embryonic Development , Genetics , Epigenesis, Genetic , Gene Expression Regulation , RNA Processing, Post-Transcriptional , RNA, Messenger , Metabolism
16.
Article in Chinese | WPRIM | ID: wpr-774318

ABSTRACT

Lymphomas are traditionally divided into Hodgkin's lymphoma and non-Hodgkin's lymphoma(NHL), the NHL is a common hematological cancer, which represents a wide spectrum of illnesses from the most indolent to the most aggressive malignancies, and the detection of related molecular targets will be needed for diagosing each subtype of NHL. Advances in understanding the pathogenesis of NHL have improved the precision of diagnosis and the prognosis evaluation of patients with this disorder, such as chromosomal translocation leading to the up-regulation of oncogene expression. Besides, the deletion of several tumor suppressor genes may cause excessive proliferation in tumor cells, and the single nucleotide polymorphism (SNP) determines the differences of susceptibility, drug-resistance and prognosis of NHL. In addition, DNA methylation, histone modification, non-coding RNA and other epigenetic phenomena play an increasingly important role in the diagnosis, selection of clinical drugs and evaluation of prognosis of NHL. In this review, the recent progress of researches on chromosome translocation, deletion of tumor suppression genes, gene poly-morphism and epigenetics are summarized.


Subject(s)
DNA Methylation , Epigenesis, Genetic , Humans , Lymphoma, Non-Hodgkin , Prognosis
17.
Article in English | WPRIM | ID: wpr-772940

ABSTRACT

Enhancers activate transcription in a distance-, orientation-, and position-independent manner, which makes them difficult to be identified. Self-transcribing active regulatory region sequencing (STARR-seq) measures the enhancer activity of millions of DNA fragments in parallel. Here we used STARR-seq to generate a quantitative global map of rice enhancers. Most enhancers were mapped within genes, especially at the 5' untranslated regions (5'UTR) and in coding sequences. Enhancers were also frequently mapped proximal to silent and lowly-expressed genes in transposable element (TE)-rich regions. Analysis of the epigenetic features of enhancers at their endogenous loci revealed that most enhancers do not co-localize with DNase I hypersensitive sites (DHSs) and lack the enhancer mark of histone modification H3K4me1. Clustering analysis of enhancers according to their epigenetic marks revealed that about 40% of identified enhancers carried one or more epigenetic marks. Repressive H3K27me3 was frequently enriched with positive marks, H3K4me3 and/or H3K27ac, which together label enhancers. Intergenic enhancers were also predicted based on the location of DHS regions relative to genes, which overlap poorly with STARR-seq enhancers. In summary, we quantitatively identified enhancers by functional analysis in the genome of rice, an important model plant. This work provides a valuable resource for further mechanistic studies in different biological contexts.


Subject(s)
Acetylation , Base Sequence , Deoxyribonuclease I , Metabolism , Enhancer Elements, Genetic , Epigenesis, Genetic , Genes, Plant , Genomics , Methods , Histone Code , Genetics , Histones , Metabolism , Models, Genetic , Oryza , Genetics , Promoter Regions, Genetic , Genetics , Repetitive Sequences, Nucleic Acid , Genetics , Sequence Analysis, DNA , Transcription, Genetic
18.
Article in Chinese | WPRIM | ID: wpr-775996

ABSTRACT

Leukemia is a disease featured by the malignant proliferation of hematopoietic stem cells or progenitor cells in the blood system.While chemotherapy remains its mainstream treatment,disease relapse and drug resistance are still challenging problems.As one of the epigenetic mechanisms,histone methylation is involved in cell proliferation,differentiation,and apoptosis by regulating gene transcription.Recent studies have found that the histone demethylase lysine-specific demethylase 6A(KDM6A),also known as ubiquitously transcribed tetratricopeptide repeat on chromosome X(UTX),is closely related to the occurrence of a variety of tumors,especially leukemia.KDM6A activates gene expression by demethylating H3K27me3 to H3K27me2 or H3K27me1.Besides,KDM6A can regulate the activation of the target gene transcription through its non-demethylase functions.It can serve as the subunit of complex of proteins associated with Set1,thus getting involved in the regulation of H3K4me1.It can be combined with yeast mating type conversion/sucrose unfermented complex family to promote the formation of an open chromatin conformation.Finally,it can promote the production of H3K27ac.This article reviews the recent studies on the structure and biological activity of histone demethylase KDM6A(UTX)and its role in treating leukemia,thus providing a new research direction for targeted treatment of leukemia.


Subject(s)
Epigenesis, Genetic , Histone Demethylases , Metabolism , Histones , Humans , Leukemia , Therapeutics , Lysine , Nuclear Proteins , Metabolism
19.
Journal of Experimental Hematology ; (6): 1540-1547, 2019.
Article in Chinese | WPRIM | ID: wpr-775688

ABSTRACT

OBJECTIVE@#To investigate the expression, mechanism and methylation level of miR-28-5p in multiple myeloma (MM), so as to provide the expirement basis for searching new targeted therapy.@*METHODS@#RT-PCR was used to detect the expression levels of miR-28-5p and potential target CCND1 in CD138 cells of the patients with MM and bone marrow mononuclear cells of patients with iron defficiency anemia(IDA) as control, Methylation-specific PCR(MSP) was used to detect methylation levels of CpG island in LPP/miR-28-5p promoter region and the correlation with other clinical indicators was analyzed. The 5-aza-2'-deoxycytidine (5-Aza-dC,DAC) was used to treat MM cell line U266; after drug treatment,MSP was used to analyze the methylation status of the CpG islands in LPP/miR-28-5p promoter; the qPCR was used to detect the expression levels of miR-28-5p,and the regulatory mechanism of miR-28-5p expression was explored furtherly.@*RESULTS@#The methylation level of CpG island in LPP/miR-28-5p promoter region of MM patients was significantly higher than that of IDA patients. The relative expression level of miR-28-5p in MM patients was significantly lower than that of IDA patients. The relative expression level of miR-28-5p in newly diagnosed MM patients was higher than that in relapsed/progressive patients. The miR-28-5p target CCND1 was expressed at high levels in MM patients with LPP / miR-28-5p methylation, the expression level of miR-28-5p in MM patients correlated with β-MG concentration. 5-aza-dc could significantly inhibit the growth of U266 cell line, arrest the cell cycle in G phase, inhibit the biosynthesis of cellular RNA and protein and promote cell apoptosis. At the same time, up-regulation of miR-28-5p expression was found.@*CONCLUSION@#The expression of miR-28-5p in MM patients is regulated by methylation of CpG islands in the promoter region of the genome.miR-28-5p may act as a tumor suppressor gene, and its low expression may be involved in the occurrence and development of MM, suggesting that miR-28-5p may become a new target for the treatment of MM.


Subject(s)
Cell Line, Tumor , CpG Islands , DNA Methylation , Epigenesis, Genetic , Gene Expression Regulation, Neoplastic , Humans , MicroRNAs , Genetics , Multiple Myeloma , Genetics
20.
Article in Chinese | WPRIM | ID: wpr-775247

ABSTRACT

Cellular senescence is a key factor driving age-related diseases. Recent studies have revealed that senescence-associated secretory phenotype, telomere attrition, epigenetic changes, and mitochondrial autophagy damage may mediate the pathogenesis of senescence-related idiopathic pulmonary fibrosis (IPF). Reducing the level of cellular senescence or clearing senescent cells can down-regulate the expression of fibrosis factors and alleviate the symptoms of IPF. In this review, we outlined the role and mechanism of cellular senescence in IPF.


Subject(s)
Autophagy , Cellular Senescence , Epigenesis, Genetic , Gene Expression , Humans , Idiopathic Pulmonary Fibrosis
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